1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.7
6 * The 'record instruction-history' command now starts counting instructions
7 at one. This also affects the instruction ranges reported by the
8 'record function-call-history' command when given the /i modifier.
10 * The command 'record function-call-history' supports a new modifier '/c' to
11 indent the function names based on their call stack depth.
12 The fields for the '/i' and '/l' modifier have been reordered.
13 The source line range is now prefixed with 'at'.
14 The instruction range is now prefixed with 'inst'.
15 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
16 "record instruction-history" and "list" commands.
18 *** Changes in GDB 7.7
20 * Improved support for process record-replay and reverse debugging on
21 arm*-linux* targets. Support for thumb32 and syscall instruction
22 recording has been added.
24 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
26 * GDB now supports Fission DWP file format version 2.
27 http://gcc.gnu.org/wiki/DebugFission
29 * New convenience function "$_isvoid", to check whether an expression
30 is void. A void expression is an expression where the type of the
31 result is "void". For example, some convenience variables may be
32 "void" when evaluated (e.g., "$_exitcode" before the execution of
33 the program being debugged; or an undefined convenience variable).
34 Another example, when calling a function whose return type is
37 * The "maintenance print objfiles" command now takes an optional regexp.
39 * The "catch syscall" command now works on arm*-linux* targets.
41 * GDB now consistently shows "<not saved>" when printing values of
42 registers the debug info indicates have not been saved in the frame
43 and there's nowhere to retrieve them from
44 (callee-saved/call-clobbered registers):
49 (gdb) info registers rax
52 Before, the former would print "<optimized out>", and the latter
53 "*value not available*".
55 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
60 ** Frame filters and frame decorators have been added.
61 ** Temporary breakpoints are now supported.
62 ** Line tables representation has been added.
63 ** New attribute 'parent_type' for gdb.Field objects.
64 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
65 ** New attribute 'name' for gdb.Type objects.
69 Nios II ELF nios2*-*-elf
70 Nios II GNU/Linux nios2*-*-linux
71 Texas Instruments MSP430 msp430*-*-elf
73 * Removed native configurations
75 Support for these a.out NetBSD and OpenBSD obsolete configurations has
76 been removed. ELF variants of these configurations are kept supported.
78 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
79 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
80 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
81 i[34567]86-*-openbsd3.[0-3]
82 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
83 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
84 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
88 Like "catch throw", but catches a re-thrown exception.
90 Renamed from old "maint check-symtabs".
92 Perform consistency checks on symtabs.
94 Expand symtabs matching an optional regexp.
97 Display the details of GDB configure-time options.
99 maint set|show per-command
100 maint set|show per-command space
101 maint set|show per-command time
102 maint set|show per-command symtab
103 Enable display of per-command gdb resource usage.
105 remove-symbol-file FILENAME
106 remove-symbol-file -a ADDRESS
107 Remove a symbol file added via add-symbol-file. The file to remove
108 can be identified by its filename or by an address that lies within
109 the boundaries of this symbol file in memory.
112 info exceptions REGEXP
113 Display the list of Ada exceptions defined in the program being
114 debugged. If provided, only the exceptions whose names match REGEXP
119 set debug symfile off|on
121 Control display of debugging info regarding reading symbol files and
122 symbol tables within those files
124 set print raw frame-arguments
125 show print raw frame-arguments
126 Set/show whether to print frame arguments in raw mode,
127 disregarding any defined pretty-printers.
129 set remote trace-status-packet
130 show remote trace-status-packet
131 Set/show the use of remote protocol qTStatus packet.
135 Control display of debugging messages related to Nios II targets.
139 Control whether target-assisted range stepping is enabled.
141 set startup-with-shell
142 show startup-with-shell
143 Specifies whether Unix child processes are started via a shell or
148 Use the target memory cache for accesses to the code segment. This
149 improves performance of remote debugging (particularly disassembly).
151 * You can now use a literal value 'unlimited' for options that
152 interpret 0 or -1 as meaning "unlimited". E.g., "set
153 trace-buffer-size unlimited" is now an alias for "set
154 trace-buffer-size -1" and "set height unlimited" is now an alias for
157 * The "set debug symtab-create" debugging option of GDB has been changed to
158 accept a verbosity level. 0 means "off", 1 provides basic debugging
159 output, and values of 2 or greater provides more verbose output.
161 * New command-line options
163 Display the details of GDB configure-time options.
165 * The command 'tsave' can now support new option '-ctf' to save trace
166 buffer in Common Trace Format.
168 * Newly installed $prefix/bin/gcore acts as a shell interface for the
171 * GDB now implements the the C++ 'typeid' operator.
173 * The new convenience variable $_exception holds the exception being
174 thrown or caught at an exception-related catchpoint.
176 * The exception-related catchpoints, like "catch throw", now accept a
177 regular expression which can be used to filter exceptions by type.
179 * The new convenience variable $_exitsignal is automatically set to
180 the terminating signal number when the program being debugged dies
181 due to an uncaught signal.
185 ** All MI commands now accept an optional "--language" option.
186 Support for this feature can be verified by using the "-list-features"
187 command, which should contain "language-option".
189 ** The new command -info-gdb-mi-command allows the user to determine
190 whether a GDB/MI command is supported or not.
192 ** The "^error" result record returned when trying to execute an undefined
193 GDB/MI command now provides a variable named "code" whose content is the
194 "undefined-command" error code. Support for this feature can be verified
195 by using the "-list-features" command, which should contain
196 "undefined-command-error-code".
198 ** The -trace-save MI command can optionally save trace buffer in Common
201 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
203 ** The command -data-list-register-values now accepts an optional
204 "--skip-unavailable" option. When used, only the available registers
207 ** The new command -trace-frame-collected dumps collected variables,
208 computed expressions, tvars, memory and registers in a traceframe.
210 ** The commands -stack-list-locals, -stack-list-arguments and
211 -stack-list-variables now accept an option "--skip-unavailable".
212 When used, only the available locals or arguments are displayed.
214 ** The -exec-run command now accepts an optional "--start" option.
215 When used, the command follows the same semantics as the "start"
216 command, stopping the program's execution at the start of its
217 main subprogram. Support for this feature can be verified using
218 the "-list-features" command, which should contain
219 "exec-run-start-option".
221 ** The new commands -catch-assert and -catch-exceptions insert
222 catchpoints stopping the program when Ada exceptions are raised.
224 ** The new command -info-ada-exceptions provides the equivalent of
225 the new "info exceptions" command.
227 * New system-wide configuration scripts
228 A GDB installation now provides scripts suitable for use as system-wide
229 configuration scripts for the following systems:
233 * GDB now supports target-assigned range stepping with remote targets.
234 This improves the performance of stepping source lines by reducing
235 the number of control packets from/to GDB. See "New remote packets"
238 * GDB now understands the element 'tvar' in the XML traceframe info.
239 It has the id of the collected trace state variables.
241 * On S/390 targets that provide the transactional-execution feature,
242 the program interruption transaction diagnostic block (TDB) is now
243 represented as a number of additional "registers" in GDB.
249 The vCont packet supports a new 'r' action, that tells the remote
250 stub to step through an address range itself, without GDB
251 involvemement at each single-step.
253 qXfer:libraries-svr4:read's annex
254 The previously unused annex of the qXfer:libraries-svr4:read packet
255 is now used to support passing an argument list. The remote stub
256 reports support for this argument list to GDB's qSupported query.
257 The defined arguments are "start" and "prev", used to reduce work
258 necessary for library list updating, resulting in significant
261 * New features in the GDB remote stub, GDBserver
263 ** GDBserver now supports target-assisted range stepping. Currently
264 enabled on x86/x86_64 GNU/Linux targets.
266 ** GDBserver now adds element 'tvar' in the XML in the reply to
267 'qXfer:traceframe-info:read'. It has the id of the collected
268 trace state variables.
270 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
273 * New 'z' formatter for printing and examining memory, this displays the
274 value as hexadecimal zero padded on the left to the size of the type.
276 * GDB can now use Windows x64 unwinding data.
278 * The "set remotebaud" command has been replaced by "set serial baud".
279 Similarly, "show remotebaud" has been replaced by "show serial baud".
280 The "set remotebaud" and "show remotebaud" commands are still available
281 to provide backward compatibility with older versions of GDB.
283 *** Changes in GDB 7.6
285 * Target record has been renamed to record-full.
286 Record/replay is now enabled with the "record full" command.
287 This also affects settings that are associated with full record/replay
288 that have been moved from "set/show record" to "set/show record full":
290 set|show record full insn-number-max
291 set|show record full stop-at-limit
292 set|show record full memory-query
294 * A new record target "record-btrace" has been added. The new target
295 uses hardware support to record the control-flow of a process. It
296 does not support replaying the execution, but it implements the
297 below new commands for investigating the recorded execution log.
298 This new recording method can be enabled using:
302 The "record-btrace" target is only available on Intel Atom processors
303 and requires a Linux kernel 2.6.32 or later.
305 * Two new commands have been added for record/replay to give information
306 about the recorded execution without having to replay the execution.
307 The commands are only supported by "record btrace".
309 record instruction-history prints the execution history at
310 instruction granularity
312 record function-call-history prints the execution history at
315 * New native configurations
317 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
318 FreeBSD/powerpc powerpc*-*-freebsd
319 x86_64/Cygwin x86_64-*-cygwin*
320 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
324 ARM AArch64 aarch64*-*-elf
325 ARM AArch64 GNU/Linux aarch64*-*-linux
326 Lynx 178 PowerPC powerpc-*-lynx*178
327 x86_64/Cygwin x86_64-*-cygwin*
328 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
330 * If the configured location of system.gdbinit file (as given by the
331 --with-system-gdbinit option at configure time) is in the
332 data-directory (as specified by --with-gdb-datadir at configure
333 time) or in one of its subdirectories, then GDB will look for the
334 system-wide init file in the directory specified by the
335 --data-directory command-line option.
337 * New command line options:
339 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
340 other initialization files, unlike -nx which disables all of them.
342 * Removed command line options
344 -epoch This was used by the gdb mode in Epoch, an ancient fork of
347 * The 'ptype' and 'whatis' commands now accept an argument to control
350 * 'info proc' now works on some core files.
354 ** Vectors can be created with gdb.Type.vector.
356 ** Python's atexit.register now works in GDB.
358 ** Types can be pretty-printed via a Python API.
360 ** Python 3 is now supported (in addition to Python 2.4 or later)
362 ** New class gdb.Architecture exposes GDB's internal representation
363 of architecture in the Python API.
365 ** New method Frame.architecture returns the gdb.Architecture object
366 corresponding to the frame's architecture.
368 * New Python-based convenience functions:
370 ** $_memeq(buf1, buf2, length)
371 ** $_streq(str1, str2)
373 ** $_regex(str, regex)
375 * The 'cd' command now defaults to using '~' (the home directory) if not
378 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
379 default for GCC since November 2000.
381 * The command 'forward-search' can now be abbreviated as 'fo'.
383 * The command 'info tracepoints' can now display 'installed on target'
384 or 'not installed on target' for each non-pending location of tracepoint.
386 * New configure options
388 --enable-libmcheck/--disable-libmcheck
389 By default, development versions are built with -lmcheck on hosts
390 that support it, in order to help track memory corruption issues.
391 Release versions, on the other hand, are built without -lmcheck
392 by default. The --enable-libmcheck/--disable-libmcheck configure
393 options allow the user to override that default.
394 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
395 This configure option allows the user to build GDB with
396 libbabeltrace using which GDB can read Common Trace Format data.
398 * New commands (for set/show, see "New options" below)
401 Catch signals. This is similar to "handle", but allows commands and
402 conditions to be attached.
405 List the BFDs known to GDB.
407 python-interactive [command]
409 Start a Python interactive prompt, or evaluate the optional command
410 and print the result of expressions.
413 "py" is a new alias for "python".
415 enable type-printer [name]...
416 disable type-printer [name]...
417 Enable or disable type printers.
421 ** For the Renesas Super-H architecture, the "regs" command has been removed
422 (has been deprecated in GDB 7.5), and "info all-registers" should be used
427 set print type methods (on|off)
428 show print type methods
429 Control whether method declarations are displayed by "ptype".
430 The default is to show them.
432 set print type typedefs (on|off)
433 show print type typedefs
434 Control whether typedef definitions are displayed by "ptype".
435 The default is to show them.
437 set filename-display basename|relative|absolute
438 show filename-display
439 Control the way in which filenames is displayed.
440 The default is "relative", which preserves previous behavior.
442 set trace-buffer-size
443 show trace-buffer-size
444 Request target to change the size of trace buffer.
446 set remote trace-buffer-size-packet auto|on|off
447 show remote trace-buffer-size-packet
448 Control the use of the remote protocol `QTBuffer:size' packet.
452 Control display of debugging messages related to ARM AArch64.
455 set debug coff-pe-read
456 show debug coff-pe-read
457 Control display of debugging messages related to reading of COFF/PE
462 Control display of debugging messages related to Mach-O symbols
465 set debug notification
466 show debug notification
467 Control display of debugging info for async remote notification.
471 ** Command parameter changes are now notified using new async record
472 "=cmd-param-changed".
473 ** Trace frame changes caused by command "tfind" are now notified using
474 new async record "=traceframe-changed".
475 ** The creation, deletion and modification of trace state variables
476 are now notified using new async records "=tsv-created",
477 "=tsv-deleted" and "=tsv-modified".
478 ** The start and stop of process record are now notified using new
479 async record "=record-started" and "=record-stopped".
480 ** Memory changes are now notified using new async record
482 ** The data-disassemble command response will include a "fullname" field
483 containing the absolute file name when source has been requested.
484 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
485 command, to allow pattern filling of memory areas.
486 ** New commands "-catch-load"/"-catch-unload" added for intercepting
487 library load/unload events.
488 ** The response to breakpoint commands and breakpoint async records
489 includes an "installed" field containing a boolean state about each
490 non-pending tracepoint location is whether installed on target or not.
491 ** Output of the "-trace-status" command includes a "trace-file" field
492 containing the name of the trace file being examined. This field is
493 optional, and only present when examining a trace file.
494 ** The "fullname" field is now always present along with the "file" field,
495 even if the file cannot be found by GDB.
497 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
498 You must have the LZMA library available when configuring GDB for this
499 feature to be enabled. For more information, see:
500 http://fedoraproject.org/wiki/Features/MiniDebugInfo
505 Set the size of trace buffer. The remote stub reports support for this
506 packet to gdb's qSupported query.
509 Enable Branch Trace Store (BTS)-based branch tracing for the current
510 thread. The remote stub reports support for this packet to gdb's
514 Disable branch tracing for the current thread. The remote stub reports
515 support for this packet to gdb's qSupported query.
518 Read the traced branches for the current thread. The remote stub
519 reports support for this packet to gdb's qSupported query.
521 *** Changes in GDB 7.5
523 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
524 for more x32 ABI info.
526 * GDB now supports access to MIPS DSP registers on Linux targets.
528 * GDB now supports debugging microMIPS binaries.
530 * The "info os" command on GNU/Linux can now display information on
531 several new classes of objects managed by the operating system:
532 "info os procgroups" lists process groups
533 "info os files" lists file descriptors
534 "info os sockets" lists internet-domain sockets
535 "info os shm" lists shared-memory regions
536 "info os semaphores" lists semaphores
537 "info os msg" lists message queues
538 "info os modules" lists loaded kernel modules
540 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
541 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
542 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
543 options and inspect the probe arguments using the new $_probe_arg family
544 of convenience variables. You can obtain more information about SystemTap
545 in <http://sourceware.org/systemtap/>.
547 * GDB now supports reversible debugging on ARM, it allows you to
548 debug basic ARM and THUMB instructions, and provides
549 record/replay support.
551 * The option "symbol-reloading" has been deleted as it is no longer used.
555 ** GDB commands implemented in Python can now be put in command class
558 ** The "maint set python print-stack on|off" is now deleted.
560 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
561 apply "flag enum"-style pretty-printing to any enum.
563 ** gdb.lookup_symbol can now work when there is no current frame.
565 ** gdb.Symbol now has a 'line' attribute, holding the line number in
566 the source at which the symbol was defined.
568 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
569 method 'value'. The former indicates whether the symbol needs a
570 frame in order to compute its value, and the latter computes the
573 ** A new method 'referenced_value' on gdb.Value objects which can
574 dereference pointer as well as C++ reference values.
576 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
577 which return the global and static blocks (as gdb.Block objects),
578 of the underlying symbol table, respectively.
580 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
581 object associated with a PC value.
583 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
584 of the address range occupied by code for the current source line.
586 * Go language support.
587 GDB now supports debugging programs written in the Go programming
590 * GDBserver now supports stdio connections.
591 E.g. (gdb) target remote | ssh myhost gdbserver - hello
593 * The binary "gdbtui" can no longer be built or installed.
594 Use "gdb -tui" instead.
596 * GDB will now print "flag" enums specially. A flag enum is one where
597 all the enumerator values have no bits in common when pairwise
598 "and"ed. When printing a value whose type is a flag enum, GDB will
599 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
600 (gdb) print (enum E) 3
603 * The filename part of a linespec will now match trailing components
604 of a source file name. For example, "break gcc/expr.c:1000" will
605 now set a breakpoint in build/gcc/expr.c, but not
608 * The "info proc" and "generate-core-file" commands will now also
609 work on remote targets connected to GDBserver on Linux.
611 * The command "info catch" has been removed. It has been disabled
614 * The "catch exception" and "catch assert" commands now accept
615 a condition at the end of the command, much like the "break"
616 command does. For instance:
618 (gdb) catch exception Constraint_Error if Barrier = True
620 Previously, it was possible to add a condition to such catchpoints,
621 but it had to be done as a second step, after the catchpoint had been
622 created, using the "condition" command.
624 * The "info static-tracepoint-marker" command will now also work on
625 native Linux targets with in-process agent.
627 * GDB can now set breakpoints on inlined functions.
629 * The .gdb_index section has been updated to include symbols for
630 inlined functions. GDB will ignore older .gdb_index sections by
631 default, which could cause symbol files to be loaded more slowly
632 until their .gdb_index sections can be recreated. The new command
633 "set use-deprecated-index-sections on" will cause GDB to use any older
634 .gdb_index sections it finds. This will restore performance, but the
635 ability to set breakpoints on inlined functions will be lost in symbol
636 files with older .gdb_index sections.
638 The .gdb_index section has also been updated to record more information
639 about each symbol. This speeds up the "info variables", "info functions"
640 and "info types" commands when used with programs having the .gdb_index
641 section, as well as speeding up debugging with shared libraries using
642 the .gdb_index section.
644 * Ada support for GDB/MI Variable Objects has been added.
646 * GDB can now support 'breakpoint always-inserted mode' in 'record'
651 ** New command -info-os is the MI equivalent of "info os".
653 ** Output logs ("set logging" and related) now include MI output.
657 ** "set use-deprecated-index-sections on|off"
658 "show use-deprecated-index-sections on|off"
659 Controls the use of deprecated .gdb_index sections.
661 ** "catch load" and "catch unload" can be used to stop when a shared
662 library is loaded or unloaded, respectively.
664 ** "enable count" can be used to auto-disable a breakpoint after
667 ** "info vtbl" can be used to show the virtual method tables for
668 C++ and Java objects.
670 ** "explore" and its sub commands "explore value" and "explore type"
671 can be used to recursively explore values and types of
672 expressions. These commands are available only if GDB is
673 configured with '--with-python'.
675 ** "info auto-load" shows status of all kinds of auto-loaded files,
676 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
677 sequences of commands files, "info auto-load python-scripts"
678 shows status of auto-loading Python script files,
679 "info auto-load local-gdbinit" shows status of loading init file
680 (.gdbinit) from current directory and "info auto-load libthread-db" shows
681 status of inferior specific thread debugging shared library loading.
683 ** "info auto-load-scripts", "set auto-load-scripts on|off"
684 and "show auto-load-scripts" commands have been deprecated, use their
685 "info auto-load python-scripts", "set auto-load python-scripts on|off"
686 and "show auto-load python-scripts" counterparts instead.
688 ** "dprintf location,format,args..." creates a dynamic printf, which
689 is basically a breakpoint that does a printf and immediately
690 resumes your program's execution, so it is like a printf that you
691 can insert dynamically at runtime instead of at compiletime.
693 ** "set print symbol"
695 Controls whether GDB attempts to display the symbol, if any,
696 corresponding to addresses it prints. This defaults to "on", but
697 you can set it to "off" to restore GDB's previous behavior.
699 * Deprecated commands
701 ** For the Renesas Super-H architecture, the "regs" command has been
702 deprecated, and "info all-registers" should be used instead.
706 Renesas RL78 rl78-*-elf
707 HP OpenVMS ia64 ia64-hp-openvms*
709 * GDBserver supports evaluation of breakpoint conditions. When
710 support is advertised by GDBserver, GDB may be told to send the
711 breakpoint conditions in bytecode form to GDBserver. GDBserver
712 will only report the breakpoint trigger to GDB when its condition
718 show mips compression
719 Select the compressed ISA encoding used in functions that have no symbol
720 information available. The encoding can be set to either of:
723 and is updated automatically from ELF file flags if available.
725 set breakpoint condition-evaluation
726 show breakpoint condition-evaluation
727 Control whether breakpoint conditions are evaluated by GDB ("host") or by
728 GDBserver ("target"). Default option "auto" chooses the most efficient
730 This option can improve debugger efficiency depending on the speed of the
734 Disable auto-loading globally.
737 Show auto-loading setting of all kinds of auto-loaded files.
739 set auto-load gdb-scripts on|off
740 show auto-load gdb-scripts
741 Control auto-loading of GDB canned sequences of commands files.
743 set auto-load python-scripts on|off
744 show auto-load python-scripts
745 Control auto-loading of Python script files.
747 set auto-load local-gdbinit on|off
748 show auto-load local-gdbinit
749 Control loading of init file (.gdbinit) from current directory.
751 set auto-load libthread-db on|off
752 show auto-load libthread-db
753 Control auto-loading of inferior specific thread debugging shared library.
755 set auto-load scripts-directory <dir1>[:<dir2>...]
756 show auto-load scripts-directory
757 Set a list of directories from which to load auto-loaded scripts.
758 Automatically loaded Python scripts and GDB scripts are located in one
759 of the directories listed by this option.
760 The delimiter (':' above) may differ according to the host platform.
762 set auto-load safe-path <dir1>[:<dir2>...]
763 show auto-load safe-path
764 Set a list of directories from which it is safe to auto-load files.
765 The delimiter (':' above) may differ according to the host platform.
767 set debug auto-load on|off
769 Control display of debugging info for auto-loading the files above.
771 set dprintf-style gdb|call|agent
773 Control the way in which a dynamic printf is performed; "gdb"
774 requests a GDB printf command, while "call" causes dprintf to call a
775 function in the inferior. "agent" requests that the target agent
776 (such as GDBserver) do the printing.
778 set dprintf-function <expr>
779 show dprintf-function
780 set dprintf-channel <expr>
782 Set the function and optional first argument to the call when using
783 the "call" style of dynamic printf.
785 set disconnected-dprintf on|off
786 show disconnected-dprintf
787 Control whether agent-style dynamic printfs continue to be in effect
788 after GDB disconnects.
790 * New configure options
793 Configure default value for the 'set auto-load scripts-directory'
794 setting above. It defaults to '$debugdir:$datadir/auto-load',
795 $debugdir representing global debugging info directories (available
796 via 'show debug-file-directory') and $datadir representing GDB's data
797 directory (available via 'show data-directory').
799 --with-auto-load-safe-path
800 Configure default value for the 'set auto-load safe-path' setting
801 above. It defaults to the --with-auto-load-dir setting.
803 --without-auto-load-safe-path
804 Set 'set auto-load safe-path' to '/', effectively disabling this
809 z0/z1 conditional breakpoints extension
811 The z0/z1 breakpoint insertion packets have been extended to carry
812 a list of conditional expressions over to the remote stub depending on the
813 condition evaluation mode. The use of this extension can be controlled
814 via the "set remote conditional-breakpoints-packet" command.
818 Specify the signals which the remote stub may pass to the debugged
819 program without GDB involvement.
821 * New command line options
823 --init-command=FILE, -ix Like --command, -x but execute it
824 before loading inferior.
825 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
826 execute it before loading inferior.
828 *** Changes in GDB 7.4
830 * GDB now handles ambiguous linespecs more consistently; the existing
831 FILE:LINE support has been expanded to other types of linespecs. A
832 breakpoint will now be set on all matching locations in all
833 inferiors, and locations will be added or removed according to
836 * GDB now allows you to skip uninteresting functions and files when
837 stepping with the "skip function" and "skip file" commands.
839 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
840 and "show remote hardware-watchpoint-length-limit". These allows to
841 set or show the maximum length limit (in bytes) of a remote
842 target hardware watchpoint.
844 This allows e.g. to use "unlimited" hardware watchpoints with the
845 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
846 watchpoints are slower than real hardware watchpoints but are
847 significantly faster than gdb software watchpoints.
851 ** The register_pretty_printer function in module gdb.printing now takes
852 an optional `replace' argument. If True, the new printer replaces any
855 ** The "maint set python print-stack on|off" command has been
856 deprecated and will be deleted in GDB 7.5.
857 A new command: "set python print-stack none|full|message" has
858 replaced it. Additionally, the default for "print-stack" is
859 now "message", which just prints the error message without
862 ** A prompt substitution hook (prompt_hook) is now available to the
865 ** A new Python module, gdb.prompt has been added to the GDB Python
866 modules library. This module provides functionality for
867 escape sequences in prompts (used by set/show
868 extended-prompt). These escape sequences are replaced by their
871 ** Python commands and convenience-functions located in
872 'data-directory'/python/gdb/command and
873 'data-directory'/python/gdb/function are now automatically loaded
876 ** Blocks now provide four new attributes. global_block and
877 static_block will return the global and static blocks
878 respectively. is_static and is_global are boolean attributes
879 that indicate if the block is one of those two types.
881 ** Symbols now provide the "type" attribute, the type of the symbol.
883 ** The "gdb.breakpoint" function has been deprecated in favor of
886 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
887 of a function. This class is based on the "finish" command
888 available in the CLI.
890 ** Type objects for struct and union types now allow access to
891 the fields using standard Python dictionary (mapping) methods.
892 For example, "some_type['myfield']" now works, as does
895 ** A new event "gdb.new_objfile" has been added, triggered by loading a
898 ** A new function, "deep_items" has been added to the gdb.types
899 module in the GDB Python modules library. This function returns
900 an iterator over the fields of a struct or union type. Unlike
901 the standard Python "iteritems" method, it will recursively traverse
902 any anonymous fields.
906 ** "*stopped" events can report several new "reason"s, such as
909 ** Breakpoint changes are now notified using new async records, like
910 "=breakpoint-modified".
912 ** New command -ada-task-info.
914 * libthread-db-search-path now supports two special values: $sdir and $pdir.
915 $sdir specifies the default system locations of shared libraries.
916 $pdir specifies the directory where the libpthread used by the application
919 GDB no longer looks in $sdir and $pdir after it has searched the directories
920 mentioned in libthread-db-search-path. If you want to search those
921 directories, they must be specified in libthread-db-search-path.
922 The default value of libthread-db-search-path on GNU/Linux and Solaris
923 systems is now "$sdir:$pdir".
925 $pdir is not supported by gdbserver, it is currently ignored.
926 $sdir is supported by gdbserver.
928 * New configure option --with-iconv-bin.
929 When using the internationalization support like the one in the GNU C
930 library, GDB will invoke the "iconv" program to get a list of supported
931 character sets. If this program lives in a non-standard location, one can
932 use this option to specify where to find it.
934 * When natively debugging programs on PowerPC BookE processors running
935 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
936 watchpoints, which specify a mask in addition to an address to watch.
937 The mask specifies that some bits of an address (the bits which are
938 reset in the mask) should be ignored when matching the address accessed
939 by the inferior against the watchpoint address. See the "PowerPC Embedded"
940 section in the user manual for more details.
942 * The new option --once causes GDBserver to stop listening for connections once
943 the first connection is made. The listening port used by GDBserver will
944 become available after that.
946 * New commands "info macros" and "alias" have been added.
948 * New function parameters suffix @entry specifies value of function parameter
949 at the time the function got called. Entry values are available only since
955 "!" is now an alias of the "shell" command.
956 Note that no space is needed between "!" and SHELL COMMAND.
960 watch EXPRESSION mask MASK_VALUE
961 The watch command now supports the mask argument which allows creation
962 of masked watchpoints, if the current architecture supports this feature.
964 info auto-load-scripts [REGEXP]
965 This command was formerly named "maintenance print section-scripts".
966 It is now generally useful and is no longer a maintenance-only command.
968 info macro [-all] [--] MACRO
969 The info macro command has new options `-all' and `--'. The first for
970 printing all definitions of a macro. The second for explicitly specifying
971 the end of arguments and the beginning of the macro name in case the macro
972 name starts with a hyphen.
974 collect[/s] EXPRESSIONS
975 The tracepoint collect command now takes an optional modifier "/s"
976 that directs it to dereference pointer-to-character types and
977 collect the bytes of memory up to a zero byte. The behavior is
978 similar to what you see when you use the regular print command on a
979 string. An optional integer following the "/s" sets a bound on the
980 number of bytes that will be collected.
983 The trace start command now interprets any supplied arguments as a
984 note to be recorded with the trace run, with an effect similar to
985 setting the variable trace-notes.
988 The trace stop command now interprets any arguments as a note to be
989 mentioned along with the tstatus report that the trace was stopped
990 with a command. The effect is similar to setting the variable
993 * Tracepoints can now be enabled and disabled at any time after a trace
994 experiment has been started using the standard "enable" and "disable"
995 commands. It is now possible to start a trace experiment with no enabled
996 tracepoints; GDB will display a warning, but will allow the experiment to
997 begin, assuming that tracepoints will be enabled as needed while the trace
1000 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1001 locations with 4-byte instructions, when they were previously
1002 limited to locations with instructions of 5 bytes or longer.
1006 set debug dwarf2-read
1007 show debug dwarf2-read
1008 Turns on or off display of debugging messages related to reading
1009 DWARF debug info. The default is off.
1011 set debug symtab-create
1012 show debug symtab-create
1013 Turns on or off display of debugging messages related to symbol table
1014 creation. The default is off.
1017 show extended-prompt
1018 Set the GDB prompt, and allow escape sequences to be inserted to
1019 display miscellaneous information (see 'help set extended-prompt'
1020 for the list of sequences). This prompt (and any information
1021 accessed through the escape sequences) is updated every time the
1022 prompt is displayed.
1024 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1025 show print entry-values
1026 Set printing of frame argument values at function entry. In some cases
1027 GDB can determine the value of function argument which was passed by the
1028 function caller, even if the value was modified inside the called function.
1030 set debug entry-values
1031 show debug entry-values
1032 Control display of debugging info for determining frame argument values at
1033 function entry and virtual tail call frames.
1035 set basenames-may-differ
1036 show basenames-may-differ
1037 Set whether a source file may have multiple base names.
1038 (A "base name" is the name of a file with the directory part removed.
1039 Example: The base name of "/home/user/hello.c" is "hello.c".)
1040 If set, GDB will canonicalize file names (e.g., expand symlinks)
1041 before comparing them. Canonicalization is an expensive operation,
1042 but it allows the same file be known by more than one base name.
1043 If not set (the default), all source files are assumed to have just
1044 one base name, and gdb will do file name comparisons more efficiently.
1050 Set a user name and notes for the current and any future trace runs.
1051 This is useful for long-running and/or disconnected traces, to
1052 inform others (or yourself) as to who is running the trace, supply
1053 contact information, or otherwise explain what is going on.
1055 set trace-stop-notes
1056 show trace-stop-notes
1057 Set a note attached to the trace run, that is displayed when the
1058 trace has been stopped by a tstop command. This is useful for
1059 instance as an explanation, if you are stopping a trace run that was
1060 started by someone else.
1062 * New remote packets
1066 Dynamically enable a tracepoint in a started trace experiment.
1070 Dynamically disable a tracepoint in a started trace experiment.
1074 Set the user and notes of the trace run.
1078 Query the current status of a tracepoint.
1082 Query the minimum length of instruction at which a fast tracepoint may
1085 * Dcache size (number of lines) and line-size are now runtime-configurable
1086 via "set dcache line" and "set dcache line-size" commands.
1090 Texas Instruments TMS320C6x tic6x-*-*
1094 Renesas RL78 rl78-*-elf
1096 *** Changes in GDB 7.3.1
1098 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1100 *** Changes in GDB 7.3
1102 * GDB has a new command: "thread find [REGEXP]".
1103 It finds the thread id whose name, target id, or thread extra info
1104 matches the given regular expression.
1106 * The "catch syscall" command now works on mips*-linux* targets.
1108 * The -data-disassemble MI command now supports modes 2 and 3 for
1109 dumping the instruction opcodes.
1111 * New command line options
1113 -data-directory DIR Specify DIR as the "data-directory".
1114 This is mostly for testing purposes.
1116 * The "maint set python auto-load on|off" command has been renamed to
1117 "set auto-load-scripts on|off".
1119 * GDB has a new command: "set directories".
1120 It is like the "dir" command except that it replaces the
1121 source path list instead of augmenting it.
1123 * GDB now understands thread names.
1125 On GNU/Linux, "info threads" will display the thread name as set by
1126 prctl or pthread_setname_np.
1128 There is also a new command, "thread name", which can be used to
1129 assign a name internally for GDB to display.
1132 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1133 has been integrated into GDB.
1137 ** The function gdb.Write now accepts an optional keyword 'stream'.
1138 This keyword, when provided, will direct the output to either
1139 stdout, stderr, or GDB's logging output.
1141 ** Parameters can now be be sub-classed in Python, and in particular
1142 you may implement the get_set_doc and get_show_doc functions.
1143 This improves how Parameter set/show documentation is processed
1144 and allows for more dynamic content.
1146 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1147 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1148 have an is_valid method.
1150 ** Breakpoints can now be sub-classed in Python, and in particular
1151 you may implement a 'stop' function that is executed each time
1152 the inferior reaches that breakpoint.
1154 ** New function gdb.lookup_global_symbol looks up a global symbol.
1156 ** GDB values in Python are now callable if the value represents a
1157 function. For example, if 'some_value' represents a function that
1158 takes two integer parameters and returns a value, you can call
1159 that function like so:
1161 result = some_value (10,20)
1163 ** Module gdb.types has been added.
1164 It contains a collection of utilities for working with gdb.Types objects:
1165 get_basic_type, has_field, make_enum_dict.
1167 ** Module gdb.printing has been added.
1168 It contains utilities for writing and registering pretty-printers.
1169 New classes: PrettyPrinter, SubPrettyPrinter,
1170 RegexpCollectionPrettyPrinter.
1171 New function: register_pretty_printer.
1173 ** New commands "info pretty-printers", "enable pretty-printer" and
1174 "disable pretty-printer" have been added.
1176 ** gdb.parameter("directories") is now available.
1178 ** New function gdb.newest_frame returns the newest frame in the
1181 ** The gdb.InferiorThread class has a new "name" attribute. This
1182 holds the thread's name.
1184 ** Python Support for Inferior events.
1185 Python scripts can add observers to be notified of events
1186 occurring in the process being debugged.
1187 The following events are currently supported:
1188 - gdb.events.cont Continue event.
1189 - gdb.events.exited Inferior exited event.
1190 - gdb.events.stop Signal received, and Breakpoint hit events.
1194 ** GDB now puts template parameters in scope when debugging in an
1195 instantiation. For example, if you have:
1197 template<int X> int func (void) { return X; }
1199 then if you step into func<5>, "print X" will show "5". This
1200 feature requires proper debuginfo support from the compiler; it
1201 was added to GCC 4.5.
1203 ** The motion commands "next", "finish", "until", and "advance" now
1204 work better when exceptions are thrown. In particular, GDB will
1205 no longer lose control of the inferior; instead, the GDB will
1206 stop the inferior at the point at which the exception is caught.
1207 This functionality requires a change in the exception handling
1208 code that was introduced in GCC 4.5.
1210 * GDB now follows GCC's rules on accessing volatile objects when
1211 reading or writing target state during expression evaluation.
1212 One notable difference to prior behavior is that "print x = 0"
1213 no longer generates a read of x; the value of the assignment is
1214 now always taken directly from the value being assigned.
1216 * GDB now has some support for using labels in the program's source in
1217 linespecs. For instance, you can use "advance label" to continue
1218 execution to a label.
1220 * GDB now has support for reading and writing a new .gdb_index
1221 section. This section holds a fast index of DWARF debugging
1222 information and can be used to greatly speed up GDB startup and
1223 operation. See the documentation for `save gdb-index' for details.
1225 * The "watch" command now accepts an optional "-location" argument.
1226 When used, this causes GDB to watch the memory referred to by the
1227 expression. Such a watchpoint is never deleted due to it going out
1230 * GDB now supports thread debugging of core dumps on GNU/Linux.
1232 GDB now activates thread debugging using the libthread_db library
1233 when debugging GNU/Linux core dumps, similarly to when debugging
1234 live processes. As a result, when debugging a core dump file, GDB
1235 is now able to display pthread_t ids of threads. For example, "info
1236 threads" shows the same output as when debugging the process when it
1237 was live. In earlier releases, you'd see something like this:
1240 * 1 LWP 6780 main () at main.c:10
1242 While now you see this:
1245 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1247 It is also now possible to inspect TLS variables when debugging core
1250 When debugging a core dump generated on a machine other than the one
1251 used to run GDB, you may need to point GDB at the correct
1252 libthread_db library with the "set libthread-db-search-path"
1253 command. See the user manual for more details on this command.
1255 * When natively debugging programs on PowerPC BookE processors running
1256 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1257 which stop execution of the inferior whenever it executes an instruction
1258 at any address within the specified range. See the "PowerPC Embedded"
1259 section in the user manual for more details.
1261 * New features in the GDB remote stub, GDBserver
1263 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1264 and i686 LynxOS (version 5.x).
1266 ** GDBserver is now supported on Blackfin Linux.
1268 * New native configurations
1270 ia64 HP-UX ia64-*-hpux*
1274 Analog Devices, Inc. Blackfin Processor bfin-*
1276 * Ada task switching is now supported on sparc-elf targets when
1277 debugging a program using the Ravenscar Profile. For more information,
1278 see the "Tasking Support when using the Ravenscar Profile" section
1279 in the GDB user manual.
1281 * Guile support was removed.
1283 * New features in the GNU simulator
1285 ** The --map-info flag lists all known core mappings.
1287 ** CFI flashes may be simulated via the "cfi" device.
1289 *** Changes in GDB 7.2
1291 * Shared library support for remote targets by default
1293 When GDB is configured for a generic, non-OS specific target, like
1294 for example, --target=arm-eabi or one of the many *-*-elf targets,
1295 GDB now queries remote stubs for loaded shared libraries using the
1296 `qXfer:libraries:read' packet. Previously, shared library support
1297 was always disabled for such configurations.
1301 ** Argument Dependent Lookup (ADL)
1303 In C++ ADL lookup directs function search to the namespaces of its
1304 arguments even if the namespace has not been imported.
1314 Here the compiler will search for `foo' in the namespace of 'b'
1315 and find A::foo. GDB now supports this. This construct is commonly
1316 used in the Standard Template Library for operators.
1318 ** Improved User Defined Operator Support
1320 In addition to member operators, GDB now supports lookup of operators
1321 defined in a namespace and imported with a `using' directive, operators
1322 defined in the global scope, operators imported implicitly from an
1323 anonymous namespace, and the ADL operators mentioned in the previous
1325 GDB now also supports proper overload resolution for all the previously
1326 mentioned flavors of operators.
1328 ** static const class members
1330 Printing of static const class members that are initialized in the
1331 class definition has been fixed.
1333 * Windows Thread Information Block access.
1335 On Windows targets, GDB now supports displaying the Windows Thread
1336 Information Block (TIB) structure. This structure is visible either
1337 by using the new command `info w32 thread-information-block' or, by
1338 dereferencing the new convenience variable named `$_tlb', a
1339 thread-specific pointer to the TIB. This feature is also supported
1340 when remote debugging using GDBserver.
1342 * Static tracepoints
1344 Static tracepoints are calls in the user program into a tracing
1345 library. One such library is a port of the LTTng kernel tracer to
1346 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1347 When debugging with GDBserver, GDB now supports combining the GDB
1348 tracepoint machinery with such libraries. For example: the user can
1349 use GDB to probe a static tracepoint marker (a call from the user
1350 program into the tracing library) with the new "strace" command (see
1351 "New commands" below). This creates a "static tracepoint" in the
1352 breakpoint list, that can be manipulated with the same feature set
1353 as fast and regular tracepoints. E.g., collect registers, local and
1354 global variables, collect trace state variables, and define
1355 tracepoint conditions. In addition, the user can collect extra
1356 static tracepoint marker specific data, by collecting the new
1357 $_sdata internal variable. When analyzing the trace buffer, you can
1358 inspect $_sdata like any other variable available to GDB. For more
1359 information, see the "Tracepoints" chapter in GDB user manual. New
1360 remote packets have been defined to support static tracepoints, see
1361 the "New remote packets" section below.
1363 * Better reconstruction of tracepoints after disconnected tracing
1365 GDB will attempt to download the original source form of tracepoint
1366 definitions when starting a trace run, and then will upload these
1367 upon reconnection to the target, resulting in a more accurate
1368 reconstruction of the tracepoints that are in use on the target.
1372 You can now exercise direct control over the ways that GDB can
1373 affect your program. For instance, you can disallow the setting of
1374 breakpoints, so that the program can run continuously (assuming
1375 non-stop mode). In addition, the "observer" variable is available
1376 to switch all of the different controls; in observer mode, GDB
1377 cannot affect the target's behavior at all, which is useful for
1378 tasks like diagnosing live systems in the field.
1380 * The new convenience variable $_thread holds the number of the
1383 * New remote packets
1387 Return the address of the Windows Thread Information Block of a given thread.
1391 In response to several of the tracepoint packets, the target may now
1392 also respond with a number of intermediate `qRelocInsn' request
1393 packets before the final result packet, to have GDB handle
1394 relocating an instruction to execute at a different address. This
1395 is particularly useful for stubs that support fast tracepoints. GDB
1396 reports support for this feature in the qSupported packet.
1400 List static tracepoint markers in the target program.
1404 List static tracepoint markers at a given address in the target
1407 qXfer:statictrace:read
1409 Read the static trace data collected (by a `collect $_sdata'
1410 tracepoint action). The remote stub reports support for this packet
1411 to gdb's qSupported query.
1415 Send the current settings of GDB's permission flags.
1419 Send part of the source (textual) form of a tracepoint definition,
1420 which includes location, conditional, and action list.
1422 * The source command now accepts a -s option to force searching for the
1423 script in the source search path even if the script name specifies
1426 * New features in the GDB remote stub, GDBserver
1428 - GDBserver now support tracepoints (including fast tracepoints, and
1429 static tracepoints). The feature is currently supported by the
1430 i386-linux and amd64-linux builds. See the "Tracepoints support
1431 in gdbserver" section in the manual for more information.
1433 GDBserver JIT compiles the tracepoint's conditional agent
1434 expression bytecode into native code whenever possible for low
1435 overhead dynamic tracepoints conditionals. For such tracepoints,
1436 an expression that examines program state is evaluated when the
1437 tracepoint is reached, in order to determine whether to capture
1438 trace data. If the condition is simple and false, processing the
1439 tracepoint finishes very quickly and no data is gathered.
1441 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1442 for static tracepoints support.
1444 - GDBserver now supports x86_64 Windows 64-bit debugging.
1446 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1447 it understands register description.
1449 * The --batch flag now disables pagination and queries.
1451 * X86 general purpose registers
1453 GDB now supports reading/writing byte, word and double-word x86
1454 general purpose registers directly. This means you can use, say,
1455 $ah or $ax to refer, respectively, to the byte register AH and
1456 16-bit word register AX that are actually portions of the 32-bit
1457 register EAX or 64-bit register RAX.
1459 * The `commands' command now accepts a range of breakpoints to modify.
1460 A plain `commands' following a command that creates multiple
1461 breakpoints affects all the breakpoints set by that command. This
1462 applies to breakpoints set by `rbreak', and also applies when a
1463 single `break' command creates multiple breakpoints (e.g.,
1464 breakpoints on overloaded c++ functions).
1466 * The `rbreak' command now accepts a filename specification as part of
1467 its argument, limiting the functions selected by the regex to those
1468 in the specified file.
1470 * Support for remote debugging Windows and SymbianOS shared libraries
1471 from Unix hosts has been improved. Non Windows GDB builds now can
1472 understand target reported file names that follow MS-DOS based file
1473 system semantics, such as file names that include drive letters and
1474 use the backslash character as directory separator. This makes it
1475 possible to transparently use the "set sysroot" and "set
1476 solib-search-path" on Unix hosts to point as host copies of the
1477 target's shared libraries. See the new command "set
1478 target-file-system-kind" described below, and the "Commands to
1479 specify files" section in the user manual for more information.
1483 eval template, expressions...
1484 Convert the values of one or more expressions under the control
1485 of the string template to a command line, and call it.
1487 set target-file-system-kind unix|dos-based|auto
1488 show target-file-system-kind
1489 Set or show the assumed file system kind for target reported file
1492 save breakpoints <filename>
1493 Save all current breakpoint definitions to a file suitable for use
1494 in a later debugging session. To read the saved breakpoint
1495 definitions, use the `source' command.
1497 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1500 info static-tracepoint-markers
1501 Display information about static tracepoint markers in the target.
1503 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1504 Define a static tracepoint by probing a marker at the given
1505 function, line, address, or marker ID.
1509 Enable and disable observer mode.
1511 set may-write-registers on|off
1512 set may-write-memory on|off
1513 set may-insert-breakpoints on|off
1514 set may-insert-tracepoints on|off
1515 set may-insert-fast-tracepoints on|off
1516 set may-interrupt on|off
1517 Set individual permissions for GDB effects on the target. Note that
1518 some of these settings can have undesirable or surprising
1519 consequences, particularly when changed in the middle of a session.
1520 For instance, disabling the writing of memory can prevent
1521 breakpoints from being inserted, cause single-stepping to fail, or
1522 even crash your program, if you disable after breakpoints have been
1523 inserted. However, GDB should not crash.
1525 set record memory-query on|off
1526 show record memory-query
1527 Control whether to stop the inferior if memory changes caused
1528 by an instruction cannot be recorded.
1533 The disassemble command now supports "start,+length" form of two arguments.
1537 ** GDB now provides a new directory location, called the python directory,
1538 where Python scripts written for GDB can be installed. The location
1539 of that directory is <data-directory>/python, where <data-directory>
1540 is the GDB data directory. For more details, see section `Scripting
1541 GDB using Python' in the manual.
1543 ** The GDB Python API now has access to breakpoints, symbols, symbol
1544 tables, program spaces, inferiors, threads and frame's code blocks.
1545 Additionally, GDB Parameters can now be created from the API, and
1546 manipulated via set/show in the CLI.
1548 ** New functions gdb.target_charset, gdb.target_wide_charset,
1549 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1551 ** New exception gdb.GdbError.
1553 ** Pretty-printers are now also looked up in the current program space.
1555 ** Pretty-printers can now be individually enabled and disabled.
1557 ** GDB now looks for names of Python scripts to auto-load in a
1558 special section named `.debug_gdb_scripts', in addition to looking
1559 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1561 * Tracepoint actions were unified with breakpoint commands. In particular,
1562 there are no longer differences in "info break" output for breakpoints and
1563 tracepoints and the "commands" command can be used for both tracepoints and
1564 regular breakpoints.
1568 ARM Symbian arm*-*-symbianelf*
1570 * D language support.
1571 GDB now supports debugging programs written in the D programming
1574 * GDB now supports the extended ptrace interface for PowerPC which is
1575 available since Linux kernel version 2.6.34. This automatically enables
1576 any hardware breakpoints and additional hardware watchpoints available in
1577 the processor. The old ptrace interface exposes just one hardware
1578 watchpoint and no hardware breakpoints.
1580 * GDB is now able to use the Data Value Compare (DVC) register available on
1581 embedded PowerPC processors to implement in hardware simple watchpoint
1582 conditions of the form:
1584 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1586 This works in native GDB running on Linux kernels with the extended ptrace
1587 interface mentioned above.
1589 *** Changes in GDB 7.1
1593 ** Namespace Support
1595 GDB now supports importing of namespaces in C++. This enables the
1596 user to inspect variables from imported namespaces. Support for
1597 namepace aliasing has also been added. So, if a namespace is
1598 aliased in the current scope (e.g. namepace C=A; ) the user can
1599 print variables using the alias (e.g. (gdb) print C::x).
1603 All known bugs relating to the printing of virtual base class were
1604 fixed. It is now possible to call overloaded static methods using a
1609 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1610 and reinterpret_cast<> are now handled by the C++ expression parser.
1614 Xilinx MicroBlaze microblaze-*-*
1619 Xilinx MicroBlaze microblaze
1622 * Multi-program debugging.
1624 GDB now has support for multi-program (a.k.a. multi-executable or
1625 multi-exec) debugging. This allows for debugging multiple inferiors
1626 simultaneously each running a different program under the same GDB
1627 session. See "Debugging Multiple Inferiors and Programs" in the
1628 manual for more information. This implied some user visible changes
1629 in the multi-inferior support. For example, "info inferiors" now
1630 lists inferiors that are not running yet or that have exited
1631 already. See also "New commands" and "New options" below.
1633 * New tracing features
1635 GDB's tracepoint facility now includes several new features:
1637 ** Trace state variables
1639 GDB tracepoints now include support for trace state variables, which
1640 are variables managed by the target agent during a tracing
1641 experiment. They are useful for tracepoints that trigger each
1642 other, so for instance one tracepoint can count hits in a variable,
1643 and then a second tracepoint has a condition that is true when the
1644 count reaches a particular value. Trace state variables share the
1645 $-syntax of GDB convenience variables, and can appear in both
1646 tracepoint actions and condition expressions. Use the "tvariable"
1647 command to create, and "info tvariables" to view; see "Trace State
1648 Variables" in the manual for more detail.
1652 GDB now includes an option for defining fast tracepoints, which
1653 targets may implement more efficiently, such as by installing a jump
1654 into the target agent rather than a trap instruction. The resulting
1655 speedup can be by two orders of magnitude or more, although the
1656 tradeoff is that some program locations on some target architectures
1657 might not allow fast tracepoint installation, for instance if the
1658 instruction to be replaced is shorter than the jump. To request a
1659 fast tracepoint, use the "ftrace" command, with syntax identical to
1660 the regular trace command.
1662 ** Disconnected tracing
1664 It is now possible to detach GDB from the target while it is running
1665 a trace experiment, then reconnect later to see how the experiment
1666 is going. In addition, a new variable disconnected-tracing lets you
1667 tell the target agent whether to continue running a trace if the
1668 connection is lost unexpectedly.
1672 GDB now has the ability to save the trace buffer into a file, and
1673 then use that file as a target, similarly to you can do with
1674 corefiles. You can select trace frames, print data that was
1675 collected in them, and use tstatus to display the state of the
1676 tracing run at the moment that it was saved. To create a trace
1677 file, use "tsave <filename>", and to use it, do "target tfile
1680 ** Circular trace buffer
1682 You can ask the target agent to handle the trace buffer as a
1683 circular buffer, discarding the oldest trace frames to make room for
1684 newer ones, by setting circular-trace-buffer to on. This feature may
1685 not be available for all target agents.
1690 The disassemble command, when invoked with two arguments, now requires
1691 the arguments to be comma-separated.
1694 The info variables command now displays variable definitions. Files
1695 which only declare a variable are not shown.
1698 The source command is now capable of sourcing Python scripts.
1699 This feature is dependent on the debugger being build with Python
1702 Related to this enhancement is also the introduction of a new command
1703 "set script-extension" (see below).
1705 * New commands (for set/show, see "New options" below)
1707 record save [<FILENAME>]
1708 Save a file (in core file format) containing the process record
1709 execution log for replay debugging at a later time.
1711 record restore <FILENAME>
1712 Restore the process record execution log that was saved at an
1713 earlier time, for replay debugging.
1715 add-inferior [-copies <N>] [-exec <FILENAME>]
1718 clone-inferior [-copies <N>] [ID]
1719 Make a new inferior ready to execute the same program another
1720 inferior has loaded.
1725 maint info program-spaces
1726 List the program spaces loaded into GDB.
1728 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1729 show remote interrupt-sequence
1730 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1731 as the sequence to the remote target in order to interrupt the execution.
1732 Ctrl-C is a default. Some system prefers BREAK which is high level of
1733 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1734 Magic SysRq g. It is BREAK signal and character 'g'.
1736 set remote interrupt-on-connect [on | off]
1737 show remote interrupt-on-connect
1738 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1739 remote target when gdb connects to it. This is needed when you debug
1742 set remotebreak [on | off]
1744 Deprecated. Use "set/show remote interrupt-sequence" instead.
1746 tvariable $NAME [ = EXP ]
1747 Create or modify a trace state variable.
1750 List trace state variables and their values.
1752 delete tvariable $NAME ...
1753 Delete one or more trace state variables.
1756 Evaluate the given expressions without collecting anything into the
1757 trace buffer. (Valid in tracepoint actions only.)
1759 ftrace FN / FILE:LINE / *ADDR
1760 Define a fast tracepoint at the given function, line, or address.
1762 * New expression syntax
1764 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1765 GDB now parses 0b101010 identically with 42.
1769 set follow-exec-mode new|same
1770 show follow-exec-mode
1771 Control whether GDB reuses the same inferior across an exec call or
1772 creates a new one. This is useful to be able to restart the old
1773 executable after the inferior having done an exec call.
1775 set default-collect EXPR, ...
1776 show default-collect
1777 Define a list of expressions to be collected at each tracepoint.
1778 This is a useful way to ensure essential items are not overlooked,
1779 such as registers or a critical global variable.
1781 set disconnected-tracing
1782 show disconnected-tracing
1783 If set to 1, the target is instructed to continue tracing if it
1784 loses its connection to GDB. If 0, the target is to stop tracing
1787 set circular-trace-buffer
1788 show circular-trace-buffer
1789 If set to on, the target is instructed to use a circular trace buffer
1790 and discard the oldest trace frames instead of stopping the trace due
1791 to a full trace buffer. If set to off, the trace stops when the buffer
1792 fills up. Some targets may not support this.
1794 set script-extension off|soft|strict
1795 show script-extension
1796 If set to "off", the debugger does not perform any script language
1797 recognition, and all sourced files are assumed to be GDB scripts.
1798 If set to "soft" (the default), files are sourced according to
1799 filename extension, falling back to GDB scripts if the first
1801 If set to "strict", files are sourced according to filename extension.
1803 set ada trust-PAD-over-XVS on|off
1804 show ada trust-PAD-over-XVS
1805 If off, activate a workaround against a bug in the debugging information
1806 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1807 the GCC sources for more information about the GNAT encoding and
1808 PAD types in particular). It is always safe to set this option to
1809 off, but this introduces a slight performance penalty. The default
1812 * Python API Improvements
1814 ** GDB provides the new class gdb.LazyString. This is useful in
1815 some pretty-printing cases. The new method gdb.Value.lazy_string
1816 provides a simple way to create objects of this type.
1818 ** The fields returned by gdb.Type.fields now have an
1819 `is_base_class' attribute.
1821 ** The new method gdb.Type.range returns the range of an array type.
1823 ** The new method gdb.parse_and_eval can be used to parse and
1824 evaluate an expression.
1826 * New remote packets
1829 Define a trace state variable.
1832 Get the current value of a trace state variable.
1835 Set desired tracing behavior upon disconnection.
1838 Set the trace buffer to be linear or circular.
1841 Get data about the tracepoints currently in use.
1845 Process record now works correctly with hardware watchpoints.
1847 Multiple bug fixes have been made to the mips-irix port, making it
1848 much more reliable. In particular:
1849 - Debugging threaded applications is now possible again. Previously,
1850 GDB would hang while starting the program, or while waiting for
1851 the program to stop at a breakpoint.
1852 - Attaching to a running process no longer hangs.
1853 - An error occurring while loading a core file has been fixed.
1854 - Changing the value of the PC register now works again. This fixes
1855 problems observed when using the "jump" command, or when calling
1856 a function from GDB, or even when assigning a new value to $pc.
1857 - With the "finish" and "return" commands, the return value for functions
1858 returning a small array is now correctly printed.
1859 - It is now possible to break on shared library code which gets executed
1860 during a shared library init phase (code executed while executing
1861 their .init section). Previously, the breakpoint would have no effect.
1862 - GDB is now able to backtrace through the signal handler for
1863 non-threaded programs.
1865 PIE (Position Independent Executable) programs debugging is now supported.
1866 This includes debugging execution of PIC (Position Independent Code) shared
1867 libraries although for that, it should be possible to run such libraries as an
1870 *** Changes in GDB 7.0
1872 * GDB now has an interface for JIT compilation. Applications that
1873 dynamically generate code can create symbol files in memory and register
1874 them with GDB. For users, the feature should work transparently, and
1875 for JIT developers, the interface is documented in the GDB manual in the
1876 "JIT Compilation Interface" chapter.
1878 * Tracepoints may now be conditional. The syntax is as for
1879 breakpoints; either an "if" clause appended to the "trace" command,
1880 or the "condition" command is available. GDB sends the condition to
1881 the target for evaluation using the same bytecode format as is used
1882 for tracepoint actions.
1884 * The disassemble command now supports: an optional /r modifier, print the
1885 raw instructions in hex as well as in symbolic form, and an optional /m
1886 modifier to print mixed source+assembly.
1888 * Process record and replay
1890 In a architecture environment that supports ``process record and
1891 replay'', ``process record and replay'' target can record a log of
1892 the process execution, and replay it with both forward and reverse
1895 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1896 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1897 set execution-direction {forward|reverse}, for targets that support
1900 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1901 feature is available with a native GDB running on kernel version
1904 * GDB now has support for multi-byte and wide character sets on the
1905 target. Strings whose character type is wchar_t, char16_t, or
1906 char32_t are now correctly printed. GDB supports wide- and unicode-
1907 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1908 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1909 `printf'. This feature requires iconv to work properly; if your
1910 system does not have a working iconv, GDB can use GNU libiconv. See
1911 the installation instructions for more information.
1913 * GDB now supports automatic retrieval of shared library files from
1914 remote targets. To use this feature, specify a system root that begins
1915 with the `remote:' prefix, either via the `set sysroot' command or via
1916 the `--with-sysroot' configure-time option.
1918 * "info sharedlibrary" now takes an optional regex of libraries to show,
1919 and it now reports if a shared library has no debugging information.
1921 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1922 now complete on file names.
1924 * When completing in expressions, gdb will attempt to limit
1925 completions to allowable structure or union fields, where appropriate.
1926 For instance, consider:
1928 # struct example { int f1; double f2; };
1929 # struct example variable;
1932 If the user types TAB at the end of this command line, the available
1933 completions will be "f1" and "f2".
1935 * Inlined functions are now supported. They show up in backtraces, and
1936 the "step", "next", and "finish" commands handle them automatically.
1938 * GDB now supports the token-splicing (##) and stringification (#)
1939 operators when expanding macros. It also supports variable-arity
1942 * GDB now supports inspecting extra signal information, exported by
1943 the new $_siginfo convenience variable. The feature is currently
1944 implemented on linux ARM, i386 and amd64.
1946 * GDB can now display the VFP floating point registers and NEON vector
1947 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1948 can provide these registers (requires Linux 2.6.30 or later). Remote
1949 and simulator targets may also provide them.
1951 * New remote packets
1954 Search memory for a sequence of bytes.
1957 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1958 operation over reliable transport links. Use of this packet is
1959 controlled by the `set remote noack-packet' command.
1962 Kill the process with the specified process ID. Use this in preference
1963 to `k' when multiprocess protocol extensions are supported.
1966 Obtains additional operating system information
1970 Read or write additional signal information.
1972 * Removed remote protocol undocumented extension
1974 An undocumented extension to the remote protocol's `S' stop reply
1975 packet that permited the stub to pass a process id was removed.
1976 Remote servers should use the `T' stop reply packet instead.
1978 * GDB now supports multiple function calling conventions according to the
1979 DWARF-2 DW_AT_calling_convention function attribute.
1981 * The SH target utilizes the aforementioned change to distinguish between gcc
1982 and Renesas calling convention. It also adds the new CLI commands
1983 `set/show sh calling-convention'.
1985 * GDB can now read compressed debug sections, as produced by GNU gold
1986 with the --compress-debug-sections=zlib flag.
1988 * 64-bit core files are now supported on AIX.
1990 * Thread switching is now supported on Tru64.
1992 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1993 which will be allocated using malloc later in program execution.
1995 * The qXfer:libraries:read remote procotol packet now allows passing a
1996 list of section offsets.
1998 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1999 conditions handling signals delivered during attach or thread creation
2000 have also been fixed.
2002 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2003 From the user's standpoint, all unqualified instances of True and False
2004 are treated as the standard definitions, regardless of context.
2006 * GDB now parses C++ symbol and type names more flexibly. For
2009 template<typename T> class C { };
2012 GDB will now correctly handle all of:
2014 ptype C<char const *>
2015 ptype C<char const*>
2016 ptype C<const char *>
2017 ptype C<const char*>
2019 * New features in the GDB remote stub, gdbserver
2021 - The "--wrapper" command-line argument tells gdbserver to use a
2022 wrapper program to launch programs for debugging.
2024 - On PowerPC and S/390 targets, it is now possible to use a single
2025 gdbserver executable to debug both 32-bit and 64-bit programs.
2026 (This requires gdbserver itself to be built as a 64-bit executable.)
2028 - gdbserver uses the new noack protocol mode for TCP connections to
2029 reduce communications latency, if also supported and enabled in GDB.
2031 - Support for the sparc64-linux-gnu target is now included in
2034 - The amd64-linux build of gdbserver now supports debugging both
2035 32-bit and 64-bit programs.
2037 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2038 now support hardware watchpoints, and will use them automatically
2043 GDB now has support for scripting using Python. Whether this is
2044 available is determined at configure time.
2046 New GDB commands can now be written in Python.
2048 * Ada tasking support
2050 Ada tasks can now be inspected in GDB. The following commands have
2054 Print the list of Ada tasks.
2056 Print detailed information about task number N.
2058 Print the task number of the current task.
2060 Switch the context of debugging to task number N.
2062 * Support for user-defined prefixed commands. The "define" command can
2063 add new commands to existing prefixes, e.g. "target".
2065 * Multi-inferior, multi-process debugging.
2067 GDB now has generalized support for multi-inferior debugging. See
2068 "Debugging Multiple Inferiors" in the manual for more information.
2069 Although availability still depends on target support, the command
2070 set is more uniform now. The GNU/Linux specific multi-forks support
2071 has been migrated to this new framework. This implied some user
2072 visible changes; see "New commands" and also "Removed commands"
2075 * Target descriptions can now describe the target OS ABI. See the
2076 "Target Description Format" section in the user manual for more
2079 * Target descriptions can now describe "compatible" architectures
2080 to indicate that the target can execute applications for a different
2081 architecture in addition to those for the main target architecture.
2082 See the "Target Description Format" section in the user manual for
2085 * Multi-architecture debugging.
2087 GDB now includes general supports for debugging applications on
2088 hybrid systems that use more than one single processor architecture
2089 at the same time. Each such hybrid architecture still requires
2090 specific support to be added. The only hybrid architecture supported
2091 in this version of GDB is the Cell Broadband Engine.
2093 * GDB now supports integrated debugging of Cell/B.E. applications that
2094 use both the PPU and SPU architectures. To enable support for hybrid
2095 Cell/B.E. debugging, you need to configure GDB to support both the
2096 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2097 --enable-targets configure option.
2099 * Non-stop mode debugging.
2101 For some targets, GDB now supports an optional mode of operation in
2102 which you can examine stopped threads while other threads continue
2103 to execute freely. This is referred to as non-stop mode, with the
2104 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2105 section in the user manual for more information.
2107 To be able to support remote non-stop debugging, a remote stub needs
2108 to implement the non-stop mode remote protocol extensions, as
2109 described in the "Remote Non-Stop" section of the user manual. The
2110 GDB remote stub, gdbserver, has been adjusted to support these
2111 extensions on linux targets.
2113 * New commands (for set/show, see "New options" below)
2115 catch syscall [NAME(S) | NUMBER(S)]
2116 Catch system calls. Arguments, which should be names of system
2117 calls or their numbers, mean catch only those syscalls. Without
2118 arguments, every syscall will be caught. When the inferior issues
2119 any of the specified syscalls, GDB will stop and announce the system
2120 call, both when it is called and when its call returns. This
2121 feature is currently available with a native GDB running on the
2122 Linux Kernel, under the following architectures: x86, x86_64,
2123 PowerPC and PowerPC64.
2125 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2127 Search memory for a sequence of bytes.
2129 maint set python print-stack
2130 maint show python print-stack
2131 Show a stack trace when an error is encountered in a Python script.
2134 Invoke CODE by passing it to the Python interpreter.
2139 These allow macros to be defined, undefined, and listed
2143 Show operating system information about processes.
2146 List the inferiors currently under GDB's control.
2149 Switch focus to inferior number NUM.
2152 Detach from inferior number NUM.
2155 Kill inferior number NUM.
2159 set spu stop-on-load
2160 show spu stop-on-load
2161 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2163 set spu auto-flush-cache
2164 show spu auto-flush-cache
2165 Control whether to automatically flush the software-managed cache
2166 during Cell/B.E. debugging.
2168 set sh calling-convention
2169 show sh calling-convention
2170 Control the calling convention used when calling SH target functions.
2173 show debug timestamp
2174 Control display of timestamps with GDB debugging output.
2176 set disassemble-next-line
2177 show disassemble-next-line
2178 Control display of disassembled source lines or instructions when
2181 set remote noack-packet
2182 show remote noack-packet
2183 Set/show the use of remote protocol QStartNoAckMode packet. See above
2184 under "New remote packets."
2186 set remote query-attached-packet
2187 show remote query-attached-packet
2188 Control use of remote protocol `qAttached' (query-attached) packet.
2190 set remote read-siginfo-object
2191 show remote read-siginfo-object
2192 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2195 set remote write-siginfo-object
2196 show remote write-siginfo-object
2197 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2200 set remote reverse-continue
2201 show remote reverse-continue
2202 Control use of remote protocol 'bc' (reverse-continue) packet.
2204 set remote reverse-step
2205 show remote reverse-step
2206 Control use of remote protocol 'bs' (reverse-step) packet.
2208 set displaced-stepping
2209 show displaced-stepping
2210 Control displaced stepping mode. Displaced stepping is a way to
2211 single-step over breakpoints without removing them from the debuggee.
2212 Also known as "out-of-line single-stepping".
2215 show debug displaced
2216 Control display of debugging info for displaced stepping.
2218 maint set internal-error
2219 maint show internal-error
2220 Control what GDB does when an internal error is detected.
2222 maint set internal-warning
2223 maint show internal-warning
2224 Control what GDB does when an internal warning is detected.
2229 Use a wrapper program to launch programs for debugging.
2231 set multiple-symbols (all|ask|cancel)
2232 show multiple-symbols
2233 The value of this variable can be changed to adjust the debugger behavior
2234 when an expression or a breakpoint location contains an ambiguous symbol
2235 name (an overloaded function name, for instance).
2237 set breakpoint always-inserted
2238 show breakpoint always-inserted
2239 Keep breakpoints always inserted in the target, as opposed to inserting
2240 them when resuming the target, and removing them when the target stops.
2241 This option can improve debugger performance on slow remote targets.
2243 set arm fallback-mode (arm|thumb|auto)
2244 show arm fallback-mode
2245 set arm force-mode (arm|thumb|auto)
2247 These commands control how ARM GDB determines whether instructions
2248 are ARM or Thumb. The default for both settings is auto, which uses
2249 the current CPSR value for instructions without symbols; previous
2250 versions of GDB behaved as if "set arm fallback-mode arm".
2252 set disable-randomization
2253 show disable-randomization
2254 Standalone programs run with the virtual address space randomization enabled
2255 by default on some platforms. This option keeps the addresses stable across
2256 multiple debugging sessions.
2260 Control whether other threads are stopped or not when some thread hits
2265 Requests that asynchronous execution is enabled in the target, if available.
2266 In this case, it's possible to resume target in the background, and interact
2267 with GDB while the target is running. "show target-async" displays the
2268 current state of asynchronous execution of the target.
2270 set target-wide-charset
2271 show target-wide-charset
2272 The target-wide-charset is the name of the character set that GDB
2273 uses when printing characters whose type is wchar_t.
2275 set tcp auto-retry (on|off)
2277 set tcp connect-timeout
2278 show tcp connect-timeout
2279 These commands allow GDB to retry failed TCP connections to a remote stub
2280 with a specified timeout period; this is useful if the stub is launched
2281 in parallel with GDB but may not be ready to accept connections immediately.
2283 set libthread-db-search-path
2284 show libthread-db-search-path
2285 Control list of directories which GDB will search for appropriate
2288 set schedule-multiple (on|off)
2289 show schedule-multiple
2290 Allow GDB to resume all threads of all processes or only threads of
2291 the current process.
2295 Use more aggressive caching for accesses to the stack. This improves
2296 performance of remote debugging (particularly backtraces) without
2297 affecting correctness.
2299 set interactive-mode (on|off|auto)
2300 show interactive-mode
2301 Control whether GDB runs in interactive mode (on) or not (off).
2302 When in interactive mode, GDB waits for the user to answer all
2303 queries. Otherwise, GDB does not wait and assumes the default
2304 answer. When set to auto (the default), GDB determines which
2305 mode to use based on the stdin settings.
2310 For program forks, this is replaced by the new more generic `info
2311 inferiors' command. To list checkpoints, you can still use the
2312 `info checkpoints' command, which was an alias for the `info forks'
2316 Replaced by the new `inferior' command. To switch between
2317 checkpoints, you can still use the `restart' command, which was an
2318 alias for the `fork' command.
2321 This is removed, since some targets don't have a notion of
2322 processes. To switch between processes, you can still use the
2323 `inferior' command using GDB's own inferior number.
2326 For program forks, this is replaced by the new more generic `kill
2327 inferior' command. To delete a checkpoint, you can still use the
2328 `delete checkpoint' command, which was an alias for the `delete
2332 For program forks, this is replaced by the new more generic `detach
2333 inferior' command. To detach a checkpoint, you can still use the
2334 `detach checkpoint' command, which was an alias for the `detach
2337 * New native configurations
2339 x86/x86_64 Darwin i[34567]86-*-darwin*
2341 x86_64 MinGW x86_64-*-mingw*
2345 Lattice Mico32 lm32-*
2346 x86 DICOS i[34567]86-*-dicos*
2347 x86_64 DICOS x86_64-*-dicos*
2350 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2351 (mingw32ce) debugging.
2357 These commands were actually not implemented on any target.
2359 *** Changes in GDB 6.8
2361 * New native configurations
2363 NetBSD/hppa hppa*-*netbsd*
2364 Xtensa GNU/Linux xtensa*-*-linux*
2368 NetBSD/hppa hppa*-*-netbsd*
2369 Xtensa GNU/Lunux xtensa*-*-linux*
2371 * Change in command line behavior -- corefiles vs. process ids.
2373 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2374 attaching to process NUMBER fails, GDB no longer attempts to open a
2375 core file named NUMBER. Attaching to a program using the -c option
2376 is no longer supported. Instead, use the '-p' or '--pid' options.
2378 * GDB can now be built as a native debugger for debugging Windows x86
2379 (mingw32) Portable Executable (PE) programs.
2381 * Pending breakpoints no longer change their number when their address
2384 * GDB now supports breakpoints with multiple locations,
2385 including breakpoints on C++ constructors, inside C++ templates,
2386 and in inlined functions.
2388 * GDB's ability to debug optimized code has been improved. GDB more
2389 accurately identifies function bodies and lexical blocks that occupy
2390 more than one contiguous range of addresses.
2392 * Target descriptions can now describe registers for PowerPC.
2394 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2395 registers on PowerPC targets.
2397 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2398 targets even when the libthread_db library is not available.
2400 * The GDB remote stub, gdbserver, now supports the new file transfer
2401 commands (remote put, remote get, and remote delete).
2403 * The GDB remote stub, gdbserver, now supports run and attach in
2404 extended-remote mode.
2406 * hppa*64*-*-hpux11* target broken
2407 The debugger is unable to start a program and fails with the following
2408 error: "Error trying to get information about dynamic linker".
2409 The gdb-6.7 release is also affected.
2411 * GDB now supports the --enable-targets= configure option to allow
2412 building a single GDB executable that supports multiple remote
2413 target architectures.
2415 * GDB now supports debugging C and C++ programs which use the
2416 Decimal Floating Point extension. In addition, the PowerPC target
2417 now has a set of pseudo-registers to inspect decimal float values
2418 stored in two consecutive float registers.
2420 * The -break-insert MI command can optionally create pending
2423 * Improved support for debugging Ada
2424 Many improvements to the Ada language support have been made. These
2426 - Better support for Ada2005 interface types
2427 - Improved handling of arrays and slices in general
2428 - Better support for Taft-amendment types
2429 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2431 - Improved command completion in Ada
2434 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2439 set print frame-arguments (all|scalars|none)
2440 show print frame-arguments
2441 The value of this variable can be changed to control which argument
2442 values should be printed by the debugger when displaying a frame.
2447 Transfer files to and from a remote target, and delete remote files.
2454 Transfer files to and from a remote target, and delete remote files.
2456 * New remote packets
2463 Open, close, read, write, and delete files on the remote system.
2466 Attach to an existing process on the remote system, in extended-remote
2470 Run a new process on the remote system, in extended-remote mode.
2472 *** Changes in GDB 6.7
2474 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2475 bfd, libiberty and opcodes, as revealed by static analysis donated by
2476 Coverity, Inc. (http://scan.coverity.com).
2478 * When looking up multiply-defined global symbols, GDB will now prefer the
2479 symbol definition in the current shared library if it was built using the
2480 -Bsymbolic linker option.
2482 * When the Text User Interface (TUI) is not configured, GDB will now
2483 recognize the -tui command-line option and print a message that the TUI
2486 * The GDB remote stub, gdbserver, now has lower overhead for high
2487 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2489 * GDB for MIPS targets now autodetects whether a remote target provides
2490 32-bit or 64-bit register values.
2492 * Support for C++ member pointers has been improved.
2494 * GDB now understands XML target descriptions, which specify the
2495 target's overall architecture. GDB can read a description from
2496 a local file or over the remote serial protocol.
2498 * Vectors of single-byte data use a new integer type which is not
2499 automatically displayed as character or string data.
2501 * The /s format now works with the print command. It displays
2502 arrays of single-byte integers and pointers to single-byte integers
2505 * Target descriptions can now describe target-specific registers,
2506 for architectures which have implemented the support (currently
2507 only ARM, M68K, and MIPS).
2509 * GDB and the GDB remote stub, gdbserver, now support the XScale
2512 * The GDB remote stub, gdbserver, has been updated to support
2513 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2514 has been rewritten to use the standard GDB remote protocol.
2516 * GDB can now step into C++ functions which are called through thunks.
2518 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2520 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2521 layout. It also supports a TextSeg= and DataSeg= response when only
2522 segment base addresses (rather than offsets) are available.
2524 * The /i format now outputs any trailing branch delay slot instructions
2525 immediately following the last instruction within the count specified.
2527 * The GDB remote protocol "T" stop reply packet now supports a
2528 "library" response. Combined with the new "qXfer:libraries:read"
2529 packet, this response allows GDB to debug shared libraries on targets
2530 where the operating system manages the list of loaded libraries (e.g.
2531 Windows and SymbianOS).
2533 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2534 (DLLs) on Windows and Windows CE targets.
2536 * GDB now supports a faster verification that a .debug file matches its binary
2537 according to its build-id signature, if the signature is present.
2543 Enable or disable hardware flow control (RTS/CTS) on the serial port
2544 when debugging using remote targets.
2546 set mem inaccessible-by-default
2547 show mem inaccessible-by-default
2548 If the target supplies a memory map, for instance via the remote
2549 protocol's "qXfer:memory-map:read" packet, setting this variable
2550 prevents GDB from accessing memory outside the memory map. This
2551 is useful for targets with memory mapped registers or which react
2552 badly to accesses of unmapped address space.
2554 set breakpoint auto-hw
2555 show breakpoint auto-hw
2556 If the target supplies a memory map, for instance via the remote
2557 protocol's "qXfer:memory-map:read" packet, setting this variable
2558 lets GDB use hardware breakpoints automatically for memory regions
2559 where it can not use software breakpoints. This covers both the
2560 "break" command and internal breakpoints used for other commands
2561 including "next" and "finish".
2564 catch exception unhandled
2565 Stop the program execution when Ada exceptions are raised.
2568 Stop the program execution when an Ada assertion failed.
2572 Set an alternate system root for target files. This is a more
2573 general version of "set solib-absolute-prefix", which is now
2574 an alias to "set sysroot".
2577 Provide extended SPU facility status information. This set of
2578 commands is available only when debugging the Cell/B.E. SPU
2581 * New native configurations
2583 OpenBSD/sh sh*-*openbsd*
2586 unset tdesc filename
2588 Use the specified local file as an XML target description, and do
2589 not query the target for its built-in description.
2593 OpenBSD/sh sh*-*-openbsd*
2594 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2595 Toshiba Media Processor mep-elf
2597 * New remote packets
2600 Ignore the specified signals; pass them directly to the debugged program
2601 without stopping other threads or reporting them to GDB.
2603 qXfer:features:read:
2604 Read an XML target description from the target, which describes its
2609 Read or write contents of an spufs file on the target system. These
2610 packets are available only on the Cell/B.E. SPU architecture.
2612 qXfer:libraries:read:
2613 Report the loaded shared libraries. Combined with new "T" packet
2614 response, this packet allows GDB to debug shared libraries on
2615 targets where the operating system manages the list of loaded
2616 libraries (e.g. Windows and SymbianOS).
2620 Support for these obsolete configurations has been removed.
2628 i[34567]86-*-lynxos*
2629 i[34567]86-*-netware*
2630 i[34567]86-*-sco3.2v5*
2631 i[34567]86-*-sco3.2v4*
2633 i[34567]86-*-sysv4.2*
2636 i[34567]86-*-unixware2*
2637 i[34567]86-*-unixware*
2646 * Other removed features
2653 Various m68k-only ROM monitors.
2660 Various Renesas ROM monitors and debugging interfaces for SH and
2665 Support for a Macraigor serial interface to on-chip debugging.
2666 GDB does not directly support the newer parallel or USB
2671 A debug information format. The predecessor to DWARF 2 and
2672 DWARF 3, which are still supported.
2674 Support for the HP aCC compiler on HP-UX/PA-RISC
2676 SOM-encapsulated symbolic debugging information, automatic
2677 invocation of pxdb, and the aCC custom C++ ABI. This does not
2678 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2679 with aCC can still be debugged on an assembly level.
2681 MIPS ".pdr" sections
2683 A MIPS-specific format used to describe stack frame layout
2684 in debugging information.
2688 GDB could work with an older version of Guile to debug
2689 the interpreter and Scheme programs running in it.
2691 set mips stack-arg-size
2692 set mips saved-gpreg-size
2694 Use "set mips abi" to control parameter passing for MIPS.
2696 *** Changes in GDB 6.6
2701 Cell Broadband Engine SPU spu-elf
2703 * GDB can now be configured as a cross-debugger targeting native Windows
2704 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2705 running on a Windows system over TCP/IP to debug Windows programs.
2707 * The GDB remote stub, gdbserver, has been updated to support Windows and
2708 Cygwin debugging. Both single-threaded and multi-threaded programs are
2711 * The "set trust-readonly-sections" command works again. This command was
2712 broken in GDB 6.3, 6.4, and 6.5.
2714 * The "load" command now supports writing to flash memory, if the remote
2715 stub provides the required support.
2717 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2718 longer requires symbolic debug information (e.g. DWARF-2).
2723 unset substitute-path
2724 show substitute-path
2725 Manage a list of substitution rules that GDB uses to rewrite the name
2726 of the directories where the sources are located. This can be useful
2727 for instance when the sources were moved to a different location
2728 between compilation and debugging.
2732 Print each CLI command as it is executed. Each command is prefixed with
2733 a number of `+' symbols representing the nesting depth.
2734 The source command now has a `-v' option to enable the same feature.
2738 The ARM Demon monitor support (RDP protocol, "target rdp").
2740 Kernel Object Display, an embedded debugging feature which only worked with
2741 an obsolete version of Cisco IOS.
2743 The 'set download-write-size' and 'show download-write-size' commands.
2745 * New remote packets
2748 Tell a stub about GDB client features, and request remote target features.
2749 The first feature implemented is PacketSize, which allows the target to
2750 specify the size of packets it can handle - to minimize the number of
2751 packets required and improve performance when connected to a remote
2755 Fetch an OS auxilliary vector from the remote stub. This packet is a
2756 more efficient replacement for qPart:auxv:read.
2758 qXfer:memory-map:read:
2759 Fetch a memory map from the remote stub, including information about
2760 RAM, ROM, and flash memory devices.
2765 Erase and program a flash memory device.
2767 * Removed remote packets
2770 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2771 used it, and only gdbserver implemented it.
2773 *** Changes in GDB 6.5
2777 Renesas M32C/M16C m32c-elf
2779 Morpho Technologies ms1 ms1-elf
2783 init-if-undefined Initialize a convenience variable, but
2784 only if it doesn't already have a value.
2786 The following commands are presently only implemented for native GNU/Linux:
2788 checkpoint Save a snapshot of the program state.
2790 restart <n> Return the program state to a
2791 previously saved state.
2793 info checkpoints List currently saved checkpoints.
2795 delete-checkpoint <n> Delete a previously saved checkpoint.
2797 set|show detach-on-fork Tell gdb whether to detach from a newly
2798 forked process, or to keep debugging it.
2800 info forks List forks of the user program that
2801 are available to be debugged.
2803 fork <n> Switch to debugging one of several
2804 forks of the user program that are
2805 available to be debugged.
2807 delete-fork <n> Delete a fork from the list of forks
2808 that are available to be debugged (and
2809 kill the forked process).
2811 detach-fork <n> Delete a fork from the list of forks
2812 that are available to be debugged (and
2813 allow the process to continue).
2817 Morpho Technologies ms2 ms1-elf
2819 * Improved Windows host support
2821 GDB now builds as a cross debugger hosted on i686-mingw32, including
2822 native console support, and remote communications using either
2823 network sockets or serial ports.
2825 * Improved Modula-2 language support
2827 GDB can now print most types in the Modula-2 syntax. This includes:
2828 basic types, set types, record types, enumerated types, range types,
2829 pointer types and ARRAY types. Procedure var parameters are correctly
2830 printed and hexadecimal addresses and character constants are also
2831 written in the Modula-2 syntax. Best results can be obtained by using
2832 GNU Modula-2 together with the -gdwarf-2 command line option.
2836 The ARM rdi-share module.
2838 The Netware NLM debug server.
2840 *** Changes in GDB 6.4
2842 * New native configurations
2844 OpenBSD/arm arm*-*-openbsd*
2845 OpenBSD/mips64 mips64-*-openbsd*
2849 Morpho Technologies ms1 ms1-elf
2851 * New command line options
2853 --batch-silent As for --batch, but totally silent.
2854 --return-child-result The debugger will exist with the same value
2855 the child (debugged) program exited with.
2856 --eval-command COMMAND, -ex COMMAND
2857 Execute a single GDB CLI command. This may be
2858 specified multiple times and in conjunction
2859 with the --command (-x) option.
2861 * Deprecated commands removed
2863 The following commands, that were deprecated in 2000, have been
2867 set|show arm disassembly-flavor set|show arm disassembler
2868 othernames set arm disassembler
2869 set|show remotedebug set|show debug remote
2870 set|show archdebug set|show debug arch
2871 set|show eventdebug set|show debug event
2874 * New BSD user-level threads support
2876 It is now possible to debug programs using the user-level threads
2877 library on OpenBSD and FreeBSD. Currently supported (target)
2880 FreeBSD/amd64 x86_64-*-freebsd*
2881 FreeBSD/i386 i386-*-freebsd*
2882 OpenBSD/i386 i386-*-openbsd*
2884 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2885 are not yet supported.
2887 * New support for Matsushita MN10300 w/sim added
2888 (Work in progress). mn10300-elf.
2890 * REMOVED configurations and files
2892 VxWorks and the XDR protocol *-*-vxworks
2893 Motorola MCORE mcore-*-*
2894 National Semiconductor NS32000 ns32k-*-*
2896 * New "set print array-indexes" command
2898 After turning this setting "on", GDB prints the index of each element
2899 when displaying arrays. The default is "off" to preserve the previous
2902 * VAX floating point support
2904 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2906 * User-defined command support
2908 In addition to using $arg0..$arg9 for argument passing, it is now possible
2909 to use $argc to determine now many arguments have been passed. See the
2910 section on user-defined commands in the user manual for more information.
2912 *** Changes in GDB 6.3:
2914 * New command line option
2916 GDB now accepts -l followed by a number to set the timeout for remote
2919 * GDB works with GCC -feliminate-dwarf2-dups
2921 GDB now supports a more compact representation of DWARF-2 debug
2922 information using DW_FORM_ref_addr references. These are produced
2923 by GCC with the option -feliminate-dwarf2-dups and also by some
2924 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2925 to use -feliminate-dwarf2-dups.
2927 * Internationalization
2929 When supported by the host system, GDB will be built with
2930 internationalization (libintl). The task of marking up the sources is
2931 continued, we're looking forward to our first translation.
2935 Initial support for debugging programs compiled with the GNAT
2936 implementation of the Ada programming language has been integrated
2937 into GDB. In this release, support is limited to expression evaluation.
2939 * New native configurations
2941 GNU/Linux/m32r m32r-*-linux-gnu
2945 GDB's remote protocol now includes support for the 'p' packet. This
2946 packet is used to fetch individual registers from a remote inferior.
2948 * END-OF-LIFE registers[] compatibility module
2950 GDB's internal register infrastructure has been completely rewritten.
2951 The new infrastructure making possible the implementation of key new
2952 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2955 GDB 6.3 will be the last release to include the the registers[]
2956 compatibility module that allowed out-of-date configurations to
2957 continue to work. This change directly impacts the following
2967 powerpc bdm protocol
2969 Unless there is activity to revive these configurations, they will be
2970 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2972 * OBSOLETE configurations and files
2974 Configurations that have been declared obsolete in this release have
2975 been commented out. Unless there is activity to revive these
2976 configurations, the next release of GDB will have their sources
2977 permanently REMOVED.
2986 *** Changes in GDB 6.2.1:
2988 * MIPS `break main; run' gave an heuristic-fence-post warning
2990 When attempting to run even a simple program, a warning about
2991 heuristic-fence-post being hit would be reported. This problem has
2994 * MIPS IRIX 'long double' crashed GDB
2996 When examining a long double variable, GDB would get a segmentation
2997 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2998 IRIX long double values).
3002 A bug in the VAX stack code was causing problems with the "next"
3003 command. This problem has been fixed.
3005 *** Changes in GDB 6.2:
3007 * Fix for ``many threads''
3009 On GNU/Linux systems that use the NPTL threads library, a program
3010 rapidly creating and deleting threads would confuse GDB leading to the
3013 ptrace: No such process.
3014 thread_db_get_info: cannot get thread info: generic error
3016 This problem has been fixed.
3018 * "-async" and "-noasync" options removed.
3020 Support for the broken "-noasync" option has been removed (it caused
3023 * New ``start'' command.
3025 This command runs the program until the begining of the main procedure.
3027 * New BSD Kernel Data Access Library (libkvm) interface
3029 Using ``target kvm'' it is now possible to debug kernel core dumps and
3030 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3031 platforms. Currently supported (native-only) configurations are:
3033 FreeBSD/amd64 x86_64-*-freebsd*
3034 FreeBSD/i386 i?86-*-freebsd*
3035 NetBSD/i386 i?86-*-netbsd*
3036 NetBSD/m68k m68*-*-netbsd*
3037 NetBSD/sparc sparc-*-netbsd*
3038 OpenBSD/amd64 x86_64-*-openbsd*
3039 OpenBSD/i386 i?86-*-openbsd*
3040 OpenBSD/m68k m68*-openbsd*
3041 OpenBSD/sparc sparc-*-openbsd*
3043 * Signal trampoline code overhauled
3045 Many generic problems with GDB's signal handling code have been fixed.
3046 These include: backtraces through non-contiguous stacks; recognition
3047 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3048 call; backtrace through a signal trampoline; step into and out of
3049 signal handlers; and single-stepping in the signal trampoline.
3051 Please note that kernel bugs are a limiting factor here. These
3052 features have been shown to work on an s390 GNU/Linux system that
3053 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3055 * Cygwin support for DWARF 2 added.
3057 * New native configurations
3059 GNU/Linux/hppa hppa*-*-linux*
3060 OpenBSD/hppa hppa*-*-openbsd*
3061 OpenBSD/m68k m68*-*-openbsd*
3062 OpenBSD/m88k m88*-*-openbsd*
3063 OpenBSD/powerpc powerpc-*-openbsd*
3064 NetBSD/vax vax-*-netbsd*
3065 OpenBSD/vax vax-*-openbsd*
3067 * END-OF-LIFE frame compatibility module
3069 GDB's internal frame infrastructure has been completely rewritten.
3070 The new infrastructure making it possible to support key new features
3071 including DWARF 2 Call Frame Information. To aid in the task of
3072 migrating old configurations to this new infrastructure, a
3073 compatibility module, that allowed old configurations to continue to
3074 work, was also included.
3076 GDB 6.2 will be the last release to include this frame compatibility
3077 module. This change directly impacts the following configurations:
3087 Unless there is activity to revive these configurations, they will be
3088 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3090 * REMOVED configurations and files
3092 Sun 3, running SunOS 3 m68*-*-sunos3*
3093 Sun 3, running SunOS 4 m68*-*-sunos4*
3094 Sun 2, running SunOS 3 m68000-*-sunos3*
3095 Sun 2, running SunOS 4 m68000-*-sunos4*
3096 Motorola 680x0 running LynxOS m68*-*-lynxos*
3097 AT&T 3b1/Unix pc m68*-att-*
3098 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3099 decstation mips-dec-* mips-little-*
3100 riscos mips-*-riscos* mips-*-sysv*
3101 sonymips mips-sony-*
3102 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3104 *** Changes in GDB 6.1.1:
3106 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3108 The TUI (Text-mode User Interface) is now built as part of a default
3109 GDB configuration. It is enabled by either selecting the TUI with the
3110 command line option "-i=tui" or by running the separate "gdbtui"
3111 program. For more information on the TUI, see the manual "Debugging
3114 * Pending breakpoint support (also included in GDB 6.1)
3116 Support has been added to allow you to specify breakpoints in shared
3117 libraries that have not yet been loaded. If a breakpoint location
3118 cannot be found, and the "breakpoint pending" option is set to auto,
3119 GDB queries you if you wish to make the breakpoint pending on a future
3120 shared-library load. If and when GDB resolves the breakpoint symbol,
3121 the pending breakpoint is removed as one or more regular breakpoints
3124 Pending breakpoints are very useful for GCJ Java debugging.
3126 * Fixed ISO-C build problems
3128 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3129 non ISO-C code that stopped them being built using a more strict ISO-C
3130 compiler (e.g., IBM's C compiler).
3132 * Fixed build problem on IRIX 5
3134 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3135 wasn't able to compile compile on an IRIX 5 system.
3137 * Added execute permission to gdb/gdbserver/configure
3139 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3140 permission. This bug would cause configure to fail on a number of
3141 systems (Solaris, IRIX). Ref: server/519.
3143 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3145 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3146 has been updated to use constant array sizes.
3148 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3150 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3151 its generated DWARF Call Frame Info. This encoding was causing GDB to
3152 panic, that panic has been fixed. Ref: gdb/1628.
3154 * Fixed a problem when examining parameters in shared library code.
3156 When examining parameters in optimized shared library code generated
3157 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3158 not available''. GDB now correctly displays the variable's value.
3160 *** Changes in GDB 6.1:
3162 * Removed --with-mmalloc
3164 Support for the mmalloc memory manager has been removed, as it
3165 conflicted with the internal gdb byte cache.
3167 * Changes in AMD64 configurations
3169 The AMD64 target now includes the %cs and %ss registers. As a result
3170 the AMD64 remote protocol has changed; this affects the floating-point
3171 and SSE registers. If you rely on those registers for your debugging,
3172 you should upgrade gdbserver on the remote side.
3174 * Revised SPARC target
3176 The SPARC target has been completely revised, incorporating the
3177 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3178 support for LynxOS and SunOS 4 has been dropped. Calling functions
3179 from within GDB on operating systems with a non-executable stack
3180 (Solaris, OpenBSD) now works.
3184 GDB has a new C++ demangler which does a better job on the mangled
3185 names generated by current versions of g++. It also runs faster, so
3186 with this and other changes gdb should now start faster on large C++
3189 * DWARF 2 Location Expressions
3191 GDB support for location expressions has been extended to support function
3192 arguments and frame bases. Older versions of GDB could crash when they
3195 * C++ nested types and namespaces
3197 GDB's support for nested types and namespaces in C++ has been
3198 improved, especially if you use the DWARF 2 debugging format. (This
3199 is the default for recent versions of GCC on most platforms.)
3200 Specifically, if you have a class "Inner" defined within a class or
3201 namespace "Outer", then GDB realizes that the class's name is
3202 "Outer::Inner", not simply "Inner". This should greatly reduce the
3203 frequency of complaints about not finding RTTI symbols. In addition,
3204 if you are stopped at inside of a function defined within a namespace,
3205 GDB modifies its name lookup accordingly.
3207 * New native configurations
3209 NetBSD/amd64 x86_64-*-netbsd*
3210 OpenBSD/amd64 x86_64-*-openbsd*
3211 OpenBSD/alpha alpha*-*-openbsd*
3212 OpenBSD/sparc sparc-*-openbsd*
3213 OpenBSD/sparc64 sparc64-*-openbsd*
3215 * New debugging protocols
3217 M32R with SDI protocol m32r-*-elf*
3219 * "set prompt-escape-char" command deleted.
3221 The command "set prompt-escape-char" has been deleted. This command,
3222 and its very obscure effet on GDB's prompt, was never documented,
3223 tested, nor mentioned in the NEWS file.
3225 * OBSOLETE configurations and files
3227 Configurations that have been declared obsolete in this release have
3228 been commented out. Unless there is activity to revive these
3229 configurations, the next release of GDB will have their sources
3230 permanently REMOVED.
3232 Sun 3, running SunOS 3 m68*-*-sunos3*
3233 Sun 3, running SunOS 4 m68*-*-sunos4*
3234 Sun 2, running SunOS 3 m68000-*-sunos3*
3235 Sun 2, running SunOS 4 m68000-*-sunos4*
3236 Motorola 680x0 running LynxOS m68*-*-lynxos*
3237 AT&T 3b1/Unix pc m68*-att-*
3238 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3239 decstation mips-dec-* mips-little-*
3240 riscos mips-*-riscos* mips-*-sysv*
3241 sonymips mips-sony-*
3242 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3244 * REMOVED configurations and files
3246 SGI Irix-4.x mips-sgi-irix4 or iris4
3247 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3248 Z8000 simulator z8k-zilog-none or z8ksim
3249 Matsushita MN10200 w/simulator mn10200-*-*
3250 H8/500 simulator h8500-hitachi-hms or h8500hms
3251 HP/PA running BSD hppa*-*-bsd*
3252 HP/PA running OSF/1 hppa*-*-osf*
3253 HP/PA Pro target hppa*-*-pro*
3254 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3255 386BSD i[3456]86-*-bsd*
3256 Sequent family i[3456]86-sequent-sysv4*
3257 i[3456]86-sequent-sysv*
3258 i[3456]86-sequent-bsd*
3259 SPARC running LynxOS sparc-*-lynxos*
3260 SPARC running SunOS 4 sparc-*-sunos4*
3261 Tsqware Sparclet sparclet-*-*
3262 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3264 *** Changes in GDB 6.0:
3268 Support for debugging the Objective-C programming language has been
3269 integrated into GDB.
3271 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3273 DWARF 2's Call Frame Information makes available compiler generated
3274 information that more exactly describes the program's run-time stack.
3275 By using this information, GDB is able to provide more robust stack
3278 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3279 have been updated to use a new backtrace mechanism which includes
3280 DWARF 2 CFI support.
3284 GDB's remote protocol has been extended to include support for hosted
3285 file I/O (where the remote target uses GDB's file system). See GDB's
3286 remote protocol documentation for details.
3288 * All targets using the new architecture framework.
3290 All of GDB's targets have been updated to use the new internal
3291 architecture framework. The way is now open for future GDB releases
3292 to include cross-architecture native debugging support (i386 on amd64,
3295 * GNU/Linux's Thread Local Storage (TLS)
3297 GDB now includes support for for the GNU/Linux implementation of
3298 per-thread variables.
3300 * GNU/Linux's Native POSIX Thread Library (NPTL)
3302 GDB's thread code has been updated to work with either the new
3303 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3305 * Separate debug info.
3307 GDB, in conjunction with BINUTILS, now supports a mechanism for
3308 automatically loading debug information from a separate file. Instead
3309 of shipping full debug and non-debug versions of system libraries,
3310 system integrators can now instead ship just the stripped libraries
3311 and optional debug files.
3313 * DWARF 2 Location Expressions
3315 DWARF 2 Location Expressions allow the compiler to more completely
3316 describe the location of variables (even in optimized code) to the
3319 GDB now includes preliminary support for location expressions (support
3320 for DW_OP_piece is still missing).
3324 A number of long standing bugs that caused GDB to die while starting a
3325 Java application have been fixed. GDB's Java support is now
3326 considered "useable".
3328 * GNU/Linux support for fork, vfork, and exec.
3330 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3331 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3334 * GDB supports logging output to a file
3336 There are two new commands, "set logging" and "show logging", which can be
3337 used to capture GDB's output to a file.
3339 * The meaning of "detach" has changed for gdbserver
3341 The "detach" command will now resume the application, as documented. To
3342 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3345 * d10v, m68hc11 `regs' command deprecated
3347 The `info registers' command has been updated so that it displays the
3348 registers using a format identical to the old `regs' command.
3352 A new command, "maint set profile on/off", has been added. This command can
3353 be used to enable or disable profiling while running GDB, to profile a
3354 session or a set of commands. In addition there is a new configure switch,
3355 "--enable-profiling", which will cause GDB to be compiled with profiling
3356 data, for more informative profiling results.
3358 * Default MI syntax changed to "mi2".
3360 The default MI (machine interface) syntax, enabled by the command line
3361 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3362 "mi1", can be enabled by specifying the option "-i=mi1".
3364 Support for the original "mi0" syntax (included in GDB 5.0) has been
3367 Fix for gdb/192: removed extraneous space when displaying frame level.
3368 Fix for gdb/672: update changelist is now output in mi list format.
3369 Fix for gdb/702: a -var-assign that updates the value now shows up
3370 in a subsequent -var-update.
3372 * New native configurations.
3374 FreeBSD/amd64 x86_64-*-freebsd*
3376 * Multi-arched targets.
3378 HP/PA HPUX11 hppa*-*-hpux*
3379 Renesas M32R/D w/simulator m32r-*-elf*
3381 * OBSOLETE configurations and files
3383 Configurations that have been declared obsolete in this release have
3384 been commented out. Unless there is activity to revive these
3385 configurations, the next release of GDB will have their sources
3386 permanently REMOVED.
3388 Z8000 simulator z8k-zilog-none or z8ksim
3389 Matsushita MN10200 w/simulator mn10200-*-*
3390 H8/500 simulator h8500-hitachi-hms or h8500hms
3391 HP/PA running BSD hppa*-*-bsd*
3392 HP/PA running OSF/1 hppa*-*-osf*
3393 HP/PA Pro target hppa*-*-pro*
3394 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3395 Sequent family i[3456]86-sequent-sysv4*
3396 i[3456]86-sequent-sysv*
3397 i[3456]86-sequent-bsd*
3398 Tsqware Sparclet sparclet-*-*
3399 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3401 * REMOVED configurations and files
3404 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3405 IBM AIX PS/2 i[3456]86-*-aix
3406 i386 running Mach 3.0 i[3456]86-*-mach3*
3407 i386 running Mach i[3456]86-*-mach*
3408 i386 running OSF/1 i[3456]86-*osf1mk*
3409 HP/Apollo 68k Family m68*-apollo*-sysv*,
3411 m68*-hp-bsd*, m68*-hp-hpux*
3412 Argonaut Risc Chip (ARC) arc-*-*
3413 Mitsubishi D30V d30v-*-*
3414 Fujitsu FR30 fr30-*-elf*
3415 OS/9000 i[34]86-*-os9k
3416 I960 with MON960 i960-*-coff
3418 * MIPS $fp behavior changed
3420 The convenience variable $fp, for the MIPS, now consistently returns
3421 the address of the current frame's base. Previously, depending on the
3422 context, $fp could refer to either $sp or the current frame's base
3423 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3424 The GNU Source-Level Debugger''.
3426 *** Changes in GDB 5.3:
3428 * GNU/Linux shared library multi-threaded performance improved.
3430 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3431 `/proc', in preference to `ptrace' for memory reads. This may result
3432 in an improvement in the start-up time of multi-threaded, shared
3433 library applications when run under GDB. One GDB user writes: ``loads
3434 shared libs like mad''.
3436 * ``gdbserver'' now supports multi-threaded applications on some targets
3438 Support for debugging multi-threaded applications which use
3439 the GNU/Linux LinuxThreads package has been added for
3440 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3441 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3443 * GDB now supports C/C++ preprocessor macros.
3445 GDB now expands preprocessor macro invocations in C/C++ expressions,
3446 and provides various commands for showing macro definitions and how
3449 The new command `macro expand EXPRESSION' expands any macro
3450 invocations in expression, and shows the result.
3452 The new command `show macro MACRO-NAME' shows the definition of the
3453 macro named MACRO-NAME, and where it was defined.
3455 Most compilers don't include information about macros in the debugging
3456 information by default. In GCC 3.1, for example, you need to compile
3457 your program with the options `-gdwarf-2 -g3'. If the macro
3458 information is present in the executable, GDB will read it.
3460 * Multi-arched targets.
3462 DEC Alpha (partial) alpha*-*-*
3463 DEC VAX (partial) vax-*-*
3465 National Semiconductor NS32000 (partial) ns32k-*-*
3466 Motorola 68000 (partial) m68k-*-*
3467 Motorola MCORE mcore-*-*
3471 Fujitsu FRV architecture added by Red Hat frv*-*-*
3474 * New native configurations
3476 Alpha NetBSD alpha*-*-netbsd*
3477 SH NetBSD sh*-*-netbsdelf*
3478 MIPS NetBSD mips*-*-netbsd*
3479 UltraSPARC NetBSD sparc64-*-netbsd*
3481 * OBSOLETE configurations and files
3483 Configurations that have been declared obsolete in this release have
3484 been commented out. Unless there is activity to revive these
3485 configurations, the next release of GDB will have their sources
3486 permanently REMOVED.
3488 Mitsubishi D30V d30v-*-*
3489 OS/9000 i[34]86-*-os9k
3490 IBM AIX PS/2 i[3456]86-*-aix
3491 Fujitsu FR30 fr30-*-elf*
3492 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3493 Argonaut Risc Chip (ARC) arc-*-*
3494 i386 running Mach 3.0 i[3456]86-*-mach3*
3495 i386 running Mach i[3456]86-*-mach*
3496 i386 running OSF/1 i[3456]86-*osf1mk*
3497 HP/Apollo 68k Family m68*-apollo*-sysv*,
3499 m68*-hp-bsd*, m68*-hp-hpux*
3500 I960 with MON960 i960-*-coff
3502 * OBSOLETE languages
3504 CHILL, a Pascal like language used by telecommunications companies.
3506 * REMOVED configurations and files
3508 AMD 29k family via UDI a29k-amd-udi, udi29k
3509 A29K VxWorks a29k-*-vxworks
3510 AMD 29000 embedded, using EBMON a29k-none-none
3511 AMD 29000 embedded with COFF a29k-none-coff
3512 AMD 29000 embedded with a.out a29k-none-aout
3514 testsuite/gdb.hp/gdb.threads-hp/ directory
3516 * New command "set max-user-call-depth <nnn>"
3518 This command allows the user to limit the call depth of user-defined
3519 commands. The default is 1024.
3521 * Changes in FreeBSD/i386 native debugging.
3523 Support for the "generate-core-file" has been added.
3525 * New commands "dump", "append", and "restore".
3527 These commands allow data to be copied from target memory
3528 to a bfd-format or binary file (dump and append), and back
3529 from a file into memory (restore).
3531 * Improved "next/step" support on multi-processor Alpha Tru64.
3533 The previous single-step mechanism could cause unpredictable problems,
3534 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3535 of a software single-step mechanism prevents this.
3537 *** Changes in GDB 5.2.1:
3545 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3546 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3547 Fix, by Joel Brobecker imported from mainline.
3549 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3550 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3551 Fix, by Fred Fish, imported from mainline.
3553 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3554 Surprisingly enough, it works now.
3555 By Michal Ludvig, imported from mainline.
3557 i386 hardware watchpoint support:
3558 avoid misses on second run for some targets.
3559 By Pierre Muller, imported from mainline.
3561 *** Changes in GDB 5.2:
3563 * New command "set trust-readonly-sections on[off]".
3565 This command is a hint that tells gdb that read-only sections
3566 really are read-only (ie. that their contents will not change).
3567 In this mode, gdb will go to the object file rather than the
3568 target to read memory from read-only sections (such as ".text").
3569 This can be a significant performance improvement on some
3570 (notably embedded) targets.
3572 * New command "generate-core-file" (or "gcore").
3574 This new gdb command allows the user to drop a core file of the child
3575 process state at any time. So far it's been implemented only for
3576 GNU/Linux and Solaris, but should be relatively easily ported to other
3577 hosts. Argument is core file name (defaults to core.<pid>).
3579 * New command line option
3581 GDB now accepts --pid or -p followed by a process id.
3583 * Change in command line behavior -- corefiles vs. process ids.
3585 There is a subtle behavior in the way in which GDB handles
3586 command line arguments. The first non-flag argument is always
3587 a program to debug, but the second non-flag argument may either
3588 be a corefile or a process id. Previously, GDB would attempt to
3589 open the second argument as a corefile, and if that failed, would
3590 issue a superfluous error message and then attempt to attach it as
3591 a process. Now, if the second argument begins with a non-digit,
3592 it will be treated as a corefile. If it begins with a digit,
3593 GDB will attempt to attach it as a process, and if no such process
3594 is found, will then attempt to open it as a corefile.
3596 * Changes in ARM configurations.
3598 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3599 configuration is fully multi-arch.
3601 * New native configurations
3603 ARM NetBSD arm*-*-netbsd*
3604 x86 OpenBSD i[3456]86-*-openbsd*
3605 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3606 Sparc64 running FreeBSD sparc64-*-freebsd*
3610 Sanyo XStormy16 xstormy16-elf
3612 * OBSOLETE configurations and files
3614 Configurations that have been declared obsolete in this release have
3615 been commented out. Unless there is activity to revive these
3616 configurations, the next release of GDB will have their sources
3617 permanently REMOVED.
3619 AMD 29k family via UDI a29k-amd-udi, udi29k
3620 A29K VxWorks a29k-*-vxworks
3621 AMD 29000 embedded, using EBMON a29k-none-none
3622 AMD 29000 embedded with COFF a29k-none-coff
3623 AMD 29000 embedded with a.out a29k-none-aout
3625 testsuite/gdb.hp/gdb.threads-hp/ directory
3627 * REMOVED configurations and files
3629 TI TMS320C80 tic80-*-*
3631 PowerPC Solaris powerpcle-*-solaris*
3632 PowerPC Windows NT powerpcle-*-cygwin32
3633 PowerPC Netware powerpc-*-netware*
3634 Harris/CXUX m88k m88*-harris-cxux*
3635 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3636 ns32k-utek-sysv* ns32k-utek-*
3637 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3638 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3639 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3640 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3641 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3643 * Changes to command line processing
3645 The new `--args' feature can be used to specify command-line arguments
3646 for the inferior from gdb's command line.
3648 * Changes to key bindings
3650 There is a new `operate-and-get-next' function bound to `C-o'.
3652 *** Changes in GDB 5.1.1
3654 Fix compile problem on DJGPP.
3656 Fix a problem with floating-point registers on the i386 being
3659 Fix to stop GDB crashing on .debug_str debug info.
3661 Numerous documentation fixes.
3663 Numerous testsuite fixes.
3665 *** Changes in GDB 5.1:
3667 * New native configurations
3669 Alpha FreeBSD alpha*-*-freebsd*
3670 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3671 MIPS GNU/Linux mips*-*-linux*
3672 MIPS SGI Irix 6.x mips*-sgi-irix6*
3673 ia64 AIX ia64-*-aix*
3674 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3678 Motorola 68HC11 and 68HC12 m68hc11-elf
3680 UltraSparc running GNU/Linux sparc64-*-linux*
3682 * OBSOLETE configurations and files
3684 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3685 Harris/CXUX m88k m88*-harris-cxux*
3686 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3687 ns32k-utek-sysv* ns32k-utek-*
3688 TI TMS320C80 tic80-*-*
3690 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3691 PowerPC Solaris powerpcle-*-solaris*
3692 PowerPC Windows NT powerpcle-*-cygwin32
3693 PowerPC Netware powerpc-*-netware*
3694 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3695 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3696 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3697 Apple Macintosh (MPW) host N/A
3699 stuff.c (Program to stuff files into a specially prepared space in kdb)
3700 kdb-start.c (Main loop for the standalone kernel debugger)
3702 Configurations that have been declared obsolete in this release have
3703 been commented out. Unless there is activity to revive these
3704 configurations, the next release of GDB will have their sources
3705 permanently REMOVED.
3707 * REMOVED configurations and files
3709 Altos 3068 m68*-altos-*
3710 Convex c1-*-*, c2-*-*
3712 ARM RISCix arm-*-* (as host)
3716 * GDB has been converted to ISO C.
3718 GDB's source code has been converted to ISO C. In particular, the
3719 sources are fully protoized, and rely on standard headers being
3724 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3726 * The MI enabled by default.
3728 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3729 revised and enabled by default. Packages which use GDB as a debugging
3730 engine behind a UI or another front end are encouraged to switch to
3731 using the GDB/MI interface, instead of the old annotations interface
3732 which is now deprecated.
3734 * Support for debugging Pascal programs.
3736 GDB now includes support for debugging Pascal programs. The following
3737 main features are supported:
3739 - Pascal-specific data types such as sets;
3741 - automatic recognition of Pascal sources based on file-name
3744 - Pascal-style display of data types, variables, and functions;
3746 - a Pascal expression parser.
3748 However, some important features are not yet supported.
3750 - Pascal string operations are not supported at all;
3752 - there are some problems with boolean types;
3754 - Pascal type hexadecimal constants are not supported
3755 because they conflict with the internal variables format;
3757 - support for Pascal objects and classes is not full yet;
3759 - unlike Pascal, GDB is case-sensitive for symbol names.
3761 * Changes in completion.
3763 Commands such as `shell', `run' and `set args', which pass arguments
3764 to inferior programs, now complete on file names, similar to what
3765 users expect at the shell prompt.
3767 Commands which accept locations, such as `disassemble', `print',
3768 `breakpoint', `until', etc. now complete on filenames as well as
3769 program symbols. Thus, if you type "break foob TAB", and the source
3770 files linked into the programs include `foobar.c', that file name will
3771 be one of the candidates for completion. However, file names are not
3772 considered for completion after you typed a colon that delimits a file
3773 name from a name of a function in that file, as in "break foo.c:bar".
3775 `set demangle-style' completes on available demangling styles.
3777 * New platform-independent commands:
3779 It is now possible to define a post-hook for a command as well as a
3780 hook that runs before the command. For more details, see the
3781 documentation of `hookpost' in the GDB manual.
3783 * Changes in GNU/Linux native debugging.
3785 Support for debugging multi-threaded programs has been completely
3786 revised for all platforms except m68k and sparc. You can now debug as
3787 many threads as your system allows you to have.
3789 Attach/detach is supported for multi-threaded programs.
3791 Support for SSE registers was added for x86. This doesn't work for
3792 multi-threaded programs though.
3794 * Changes in MIPS configurations.
3796 Multi-arch support is enabled for all MIPS configurations.
3798 GDB can now be built as native debugger on SGI Irix 6.x systems for
3799 debugging n32 executables. (Debugging 64-bit executables is not yet
3802 * Unified support for hardware watchpoints in all x86 configurations.
3804 Most (if not all) native x86 configurations support hardware-assisted
3805 breakpoints and watchpoints in a unified manner. This support
3806 implements debug register sharing between watchpoints, which allows to
3807 put a virtually infinite number of watchpoints on the same address,
3808 and also supports watching regions up to 16 bytes with several debug
3811 The new maintenance command `maintenance show-debug-regs' toggles
3812 debugging print-outs in functions that insert, remove, and test
3813 watchpoints and hardware breakpoints.
3815 * Changes in the DJGPP native configuration.
3817 New command ``info dos sysinfo'' displays assorted information about
3818 the CPU, OS, memory, and DPMI server.
3820 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3821 display information about segment descriptors stored in GDT, LDT, and
3824 New commands ``info dos pde'' and ``info dos pte'' display entries
3825 from Page Directory and Page Tables (for now works with CWSDPMI only).
3826 New command ``info dos address-pte'' displays the Page Table entry for
3827 a given linear address.
3829 GDB can now pass command lines longer than 126 characters to the
3830 program being debugged (requires an update to the libdbg.a library
3831 which is part of the DJGPP development kit).
3833 DWARF2 debug info is now supported.
3835 It is now possible to `step' and `next' through calls to `longjmp'.
3837 * Changes in documentation.
3839 All GDB documentation was converted to GFDL, the GNU Free
3840 Documentation License.
3842 Tracepoints-related commands are now fully documented in the GDB
3845 TUI, the Text-mode User Interface, is now documented in the manual.
3847 Tracepoints-related commands are now fully documented in the GDB
3850 The "GDB Internals" manual now has an index. It also includes
3851 documentation of `ui_out' functions, GDB coding standards, x86
3852 hardware watchpoints, and memory region attributes.
3854 * GDB's version number moved to ``version.in''
3856 The Makefile variable VERSION has been replaced by the file
3857 ``version.in''. People creating GDB distributions should update the
3858 contents of this file.
3862 GUD support is now a standard part of the EMACS distribution.
3864 *** Changes in GDB 5.0:
3866 * Improved support for debugging FP programs on x86 targets
3868 Unified and much-improved support for debugging floating-point
3869 programs on all x86 targets. In particular, ``info float'' now
3870 displays the FP registers in the same format on all x86 targets, with
3871 greater level of detail.
3873 * Improvements and bugfixes in hardware-assisted watchpoints
3875 It is now possible to watch array elements, struct members, and
3876 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3877 on x86 targets no longer erroneously trigger when the address is
3880 * Improvements in the native DJGPP version of GDB
3882 The distribution now includes all the scripts and auxiliary files
3883 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3884 machines ``out of the box''.
3886 The DJGPP version can now debug programs that use signals. It is
3887 possible to catch signals that happened in the debuggee, deliver
3888 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3889 would kill the program being debugged.) Programs that hook hardware
3890 interrupts (keyboard, timer, etc.) can also be debugged.
3892 It is now possible to debug DJGPP programs that redirect their
3893 standard handles or switch them to raw (as opposed to cooked) mode, or
3894 even close them. The command ``run < foo > bar'' works as expected,
3895 and ``info terminal'' reports useful information about the debuggee's
3896 terminal, including raw/cooked mode, redirection, etc.
3898 The DJGPP version now uses termios functions for console I/O, which
3899 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3902 DOS-style file names with drive letters are now fully supported by
3905 It is now possible to debug DJGPP programs that switch their working
3906 directory. It is also possible to rerun the debuggee any number of
3907 times without restarting GDB; thus, you can use the same setup,
3908 breakpoints, etc. for many debugging sessions.
3910 * New native configurations
3912 ARM GNU/Linux arm*-*-linux*
3913 PowerPC GNU/Linux powerpc-*-linux*
3917 Motorola MCore mcore-*-*
3918 x86 VxWorks i[3456]86-*-vxworks*
3919 PowerPC VxWorks powerpc-*-vxworks*
3920 TI TMS320C80 tic80-*-*
3922 * OBSOLETE configurations
3924 Altos 3068 m68*-altos-*
3925 Convex c1-*-*, c2-*-*
3927 ARM RISCix arm-*-* (as host)
3930 Configurations that have been declared obsolete will be commented out,
3931 but the code will be left in place. If there is no activity to revive
3932 these configurations before the next release of GDB, the sources will
3933 be permanently REMOVED.
3935 * Gould support removed
3937 Support for the Gould PowerNode and NP1 has been removed.
3939 * New features for SVR4
3941 On SVR4 native platforms (such as Solaris), if you attach to a process
3942 without first loading a symbol file, GDB will now attempt to locate and
3943 load symbols from the running process's executable file.
3945 * Many C++ enhancements
3947 C++ support has been greatly improved. Overload resolution now works properly
3948 in almost all cases. RTTI support is on the way.
3950 * Remote targets can connect to a sub-program
3952 A popen(3) style serial-device has been added. This device starts a
3953 sub-process (such as a stand-alone simulator) and then communicates
3954 with that. The sub-program to run is specified using the syntax
3955 ``|<program> <args>'' vis:
3957 (gdb) set remotedebug 1
3958 (gdb) target extended-remote |mn10300-elf-sim program-args
3960 * MIPS 64 remote protocol
3962 A long standing bug in the mips64 remote protocol where by GDB
3963 expected certain 32 bit registers (ex SR) to be transfered as 32
3964 instead of 64 bits has been fixed.
3966 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3967 added to provide backward compatibility with older versions of GDB.
3969 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3971 The command ``set remotebinarydownload'' command has been replaced by
3972 ``set remote X-packet''. Other commands in ``set remote'' family
3973 include ``set remote P-packet''.
3975 * Breakpoint commands accept ranges.
3977 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3978 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3979 ``tracepoint passcount'' also accepts a range of tracepoints.
3981 * ``apropos'' command added.
3983 The ``apropos'' command searches through command names and
3984 documentation strings, printing out matches, making it much easier to
3985 try to find a command that does what you are looking for.
3989 A new machine oriented interface (MI) has been added to GDB. This
3990 interface is designed for debug environments running GDB as a separate
3991 process. This is part of the long term libGDB project. See the
3992 "GDB/MI" chapter of the GDB manual for further information. It can be
3993 enabled by configuring with:
3995 .../configure --enable-gdbmi
3997 *** Changes in GDB-4.18:
3999 * New native configurations
4001 HP-UX 10.20 hppa*-*-hpux10.20
4002 HP-UX 11.x hppa*-*-hpux11.0*
4003 M68K GNU/Linux m68*-*-linux*
4007 Fujitsu FR30 fr30-*-elf*
4008 Intel StrongARM strongarm-*-*
4009 Mitsubishi D30V d30v-*-*
4011 * OBSOLETE configurations
4013 Gould PowerNode, NP1 np1-*-*, pn-*-*
4015 Configurations that have been declared obsolete will be commented out,
4016 but the code will be left in place. If there is no activity to revive
4017 these configurations before the next release of GDB, the sources will
4018 be permanently REMOVED.
4022 As a compatibility experiment, GDB's source files buildsym.h and
4023 buildsym.c have been converted to pure standard C, no longer
4024 containing any K&R compatibility code. We believe that all systems in
4025 use today either come with a standard C compiler, or have a GCC port
4026 available. If this is not true, please report the affected
4027 configuration to bug-gdb@gnu.org immediately. See the README file for
4028 information about getting a standard C compiler if you don't have one
4033 GDB now uses readline 2.2.
4035 * set extension-language
4037 You can now control the mapping between filename extensions and source
4038 languages by using the `set extension-language' command. For instance,
4039 you can ask GDB to treat .c files as C++ by saying
4040 set extension-language .c c++
4041 The command `info extensions' lists all of the recognized extensions
4042 and their associated languages.
4044 * Setting processor type for PowerPC and RS/6000
4046 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4047 you can use the `set processor' command to specify what variant of the
4048 PowerPC family you are debugging. The command
4052 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4053 following PowerPC and RS6000 variants:
4055 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4056 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4058 403GC IBM PowerPC 403GC
4059 505 Motorola PowerPC 505
4060 860 Motorola PowerPC 860 or 850
4061 601 Motorola PowerPC 601
4062 602 Motorola PowerPC 602
4063 603 Motorola/IBM PowerPC 603 or 603e
4064 604 Motorola PowerPC 604 or 604e
4065 750 Motorola/IBM PowerPC 750 or 750
4067 At the moment, this command just tells GDB what to name the
4068 special-purpose processor registers. Since almost all the affected
4069 registers are inaccessible to user-level programs, this command is
4070 only useful for remote debugging in its present form.
4074 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4075 more extensive support for HP-UX. Added features include shared
4076 library support, kernel threads and hardware watchpoints for 11.00,
4077 support for HP's ANSI C and C++ compilers, and a compatibility mode
4078 for xdb and dbx commands.
4082 HP's donation includes the new concept of catchpoints, which is a
4083 generalization of the old catch command. On HP-UX, it is now possible
4084 to catch exec, fork, and vfork, as well as library loading.
4086 This means that the existing catch command has changed; its first
4087 argument now specifies the type of catch to be set up. See the
4088 output of "help catch" for a list of catchpoint types.
4090 * Debugging across forks
4092 On HP-UX, you can choose which process to debug when a fork() happens
4097 HP has donated a curses-based terminal user interface (TUI). To get
4098 it, build with --enable-tui. Although this can be enabled for any
4099 configuration, at present it only works for native HP debugging.
4101 * GDB remote protocol additions
4103 A new protocol packet 'X' that writes binary data is now available.
4104 Default behavior is to try 'X', then drop back to 'M' if the stub
4105 fails to respond. The settable variable `remotebinarydownload'
4106 allows explicit control over the use of 'X'.
4108 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4109 full 64-bit address. The command
4111 set remoteaddresssize 32
4113 can be used to revert to the old behaviour. For existing remote stubs
4114 the change should not be noticed, as the additional address information
4117 In order to assist in debugging stubs, you may use the maintenance
4118 command `packet' to send any text string to the stub. For instance,
4120 maint packet heythere
4122 sends the packet "$heythere#<checksum>". Note that it is very easy to
4123 disrupt a debugging session by sending the wrong packet at the wrong
4126 The compare-sections command allows you to compare section data on the
4127 target to what is in the executable file without uploading or
4128 downloading, by comparing CRC checksums.
4130 * Tracing can collect general expressions
4132 You may now collect general expressions at tracepoints. This requires
4133 further additions to the target-side stub; see tracepoint.c and
4134 doc/agentexpr.texi for further details.
4136 * mask-address variable for Mips
4138 For Mips targets, you may control the zeroing of the upper 32 bits of
4139 a 64-bit address by entering `set mask-address on'. This is mainly
4140 of interest to users of embedded R4xxx and R5xxx processors.
4142 * Higher serial baud rates
4144 GDB's serial code now allows you to specify baud rates 57600, 115200,
4145 230400, and 460800 baud. (Note that your host system may not be able
4146 to achieve all of these rates.)
4150 The i960 configuration now includes an initial implementation of a
4151 builtin simulator, contributed by Jim Wilson.
4154 *** Changes in GDB-4.17:
4156 * New native configurations
4158 Alpha GNU/Linux alpha*-*-linux*
4159 Unixware 2.x i[3456]86-unixware2*
4160 Irix 6.x mips*-sgi-irix6*
4161 PowerPC GNU/Linux powerpc-*-linux*
4162 PowerPC Solaris powerpcle-*-solaris*
4163 Sparc GNU/Linux sparc-*-linux*
4164 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4168 Argonaut Risc Chip (ARC) arc-*-*
4169 Hitachi H8/300S h8300*-*-*
4170 Matsushita MN10200 w/simulator mn10200-*-*
4171 Matsushita MN10300 w/simulator mn10300-*-*
4172 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4173 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4174 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4175 Mitsubishi D10V w/simulator d10v-*-*
4176 Mitsubishi M32R/D w/simulator m32r-*-elf*
4177 Tsqware Sparclet sparclet-*-*
4178 NEC V850 w/simulator v850-*-*
4180 * New debugging protocols
4182 ARM with RDI protocol arm*-*-*
4183 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4184 DDB and LSI variants of PMON protocol mips*-*-*
4185 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4186 PowerPC with SDS protocol powerpc{,le}-*-eabi
4187 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4191 All configurations can now understand and use the DWARF 2 debugging
4192 format. The choice is automatic, if the symbol file contains DWARF 2
4197 GDB now includes basic Java language support. This support is
4198 only useful with Java compilers that produce native machine code.
4200 * solib-absolute-prefix and solib-search-path
4202 For SunOS and SVR4 shared libraries, you may now set the prefix for
4203 loading absolute shared library symbol files, and the search path for
4204 locating non-absolute shared library symbol files.
4206 * Live range splitting
4208 GDB can now effectively debug code for which GCC has performed live
4209 range splitting as part of its optimization. See gdb/doc/LRS for
4210 more details on the expected format of the stabs information.
4214 GDB's support for the GNU Hurd, including thread debugging, has been
4215 updated to work with current versions of the Hurd.
4219 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4220 instruction set. ARM GDB automatically detects when Thumb
4221 instructions are in use, and adjusts disassembly and backtracing
4226 GDB's MIPS target configurations now handle the MIP16 16-bit
4231 GDB now includes support for overlays; if an executable has been
4232 linked such that multiple sections are based at the same address, GDB
4233 will decide which section to use for symbolic info. You can choose to
4234 control the decision manually, using overlay commands, or implement
4235 additional target-side support and use "overlay load-target" to bring
4236 in the overlay mapping. Do "help overlay" for more detail.
4240 The command "info symbol <address>" displays information about
4241 the symbol at the specified address.
4245 The standard remote protocol now includes an extension that allows
4246 asynchronous collection and display of trace data. This requires
4247 extensive support in the target-side debugging stub. Tracing mode
4248 includes a new interaction mode in GDB and new commands: see the
4249 file tracepoint.c for more details.
4253 Configurations for embedded MIPS now include a simulator contributed
4254 by Cygnus Solutions. The simulator supports the instruction sets
4255 of most MIPS variants.
4259 Sparc configurations may now include the ERC32 simulator contributed
4260 by the European Space Agency. The simulator is not built into
4261 Sparc targets by default; configure with --enable-sim to include it.
4265 For target configurations that may include multiple variants of a
4266 basic architecture (such as MIPS and SH), you may now set the
4267 architecture explicitly. "set arch" sets, "info arch" lists
4268 the possible architectures.
4270 *** Changes in GDB-4.16:
4272 * New native configurations
4274 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4275 M68K NetBSD m68k-*-netbsd*
4276 PowerPC AIX 4.x powerpc-*-aix*
4277 PowerPC MacOS powerpc-*-macos*
4278 PowerPC Windows NT powerpcle-*-cygwin32
4279 RS/6000 AIX 4.x rs6000-*-aix4*
4283 ARM with RDP protocol arm-*-*
4284 I960 with MON960 i960-*-coff
4285 MIPS VxWorks mips*-*-vxworks*
4286 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4287 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4289 Matra Sparclet sparclet-*-*
4293 The powerpc-eabi configuration now includes the PSIM simulator,
4294 contributed by Andrew Cagney, with assistance from Mike Meissner.
4295 PSIM is a very elaborate model of the PowerPC, including not only
4296 basic instruction set execution, but also details of execution unit
4297 performance and I/O hardware. See sim/ppc/README for more details.
4301 GDB now works with Solaris 2.5.
4303 * Windows 95/NT native
4305 GDB will now work as a native debugger on Windows 95 and Windows NT.
4306 To build it from source, you must use the "gnu-win32" environment,
4307 which uses a DLL to emulate enough of Unix to run the GNU tools.
4308 Further information, binaries, and sources are available at
4309 ftp.cygnus.com, under pub/gnu-win32.
4311 * dont-repeat command
4313 If a user-defined command includes the command `dont-repeat', then the
4314 command will not be repeated if the user just types return. This is
4315 useful if the command is time-consuming to run, so that accidental
4316 extra keystrokes don't run the same command many times.
4318 * Send break instead of ^C
4320 The standard remote protocol now includes an option to send a break
4321 rather than a ^C to the target in order to interrupt it. By default,
4322 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4324 * Remote protocol timeout
4326 The standard remote protocol includes a new variable `remotetimeout'
4327 that allows you to set the number of seconds before GDB gives up trying
4328 to read from the target. The default value is 2.
4330 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4332 By default GDB will automatically keep track of objects as they are
4333 loaded and unloaded by the dynamic linker. By using the command `set
4334 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4335 when shared library events occur, thus allowing you to set breakpoints
4336 in shared libraries which are explicitly loaded by the inferior.
4338 Note this feature does not work on hpux8. On hpux9 you must link
4339 /usr/lib/end.o into your program. This feature should work
4340 automatically on hpux10.
4342 * Irix 5.x hardware watchpoint support
4344 Irix 5 configurations now support the use of hardware watchpoints.
4346 * Mips protocol "SYN garbage limit"
4348 When debugging a Mips target using the `target mips' protocol, you
4349 may set the number of characters that GDB will ignore by setting
4350 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4351 every character. The default value is 1050.
4353 * Recording and replaying remote debug sessions
4355 If you set `remotelogfile' to the name of a file, gdb will write to it
4356 a recording of a remote debug session. This recording may then be
4357 replayed back to gdb using "gdbreplay". See gdbserver/README for
4358 details. This is useful when you have a problem with GDB while doing
4359 remote debugging; you can make a recording of the session and send it
4360 to someone else, who can then recreate the problem.
4362 * Speedups for remote debugging
4364 GDB includes speedups for downloading and stepping MIPS systems using
4365 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4366 and more efficient S-record downloading.
4368 * Memory use reductions and statistics collection
4370 GDB now uses less memory and reports statistics about memory usage.
4371 Try the `maint print statistics' command, for example.
4373 *** Changes in GDB-4.15:
4375 * Psymtabs for XCOFF
4377 The symbol reader for AIX GDB now uses partial symbol tables. This
4378 can greatly improve startup time, especially for large executables.
4380 * Remote targets use caching
4382 Remote targets now use a data cache to speed up communication with the
4383 remote side. The data cache could lead to incorrect results because
4384 it doesn't know about volatile variables, thus making it impossible to
4385 debug targets which use memory mapped I/O devices. `set remotecache
4386 off' turns the the data cache off.
4388 * Remote targets may have threads
4390 The standard remote protocol now includes support for multiple threads
4391 in the target system, using new protocol commands 'H' and 'T'. See
4392 gdb/remote.c for details.
4396 If GDB is configured with `--enable-netrom', then it will include
4397 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4398 acts as though it is a bank of ROM on the target board, but you can
4399 write into it over the network. GDB's support consists only of
4400 support for fast loading into the emulated ROM; to debug, you must use
4401 another protocol, such as standard remote protocol. The usual
4402 sequence is something like
4404 target nrom <netrom-hostname>
4406 target remote <netrom-hostname>:1235
4410 GDB now includes support for the Apple Macintosh, as a host only. It
4411 may be run as either an MPW tool or as a standalone application, and
4412 it can debug through the serial port. All the usual GDB commands are
4413 available, but to the target command, you must supply "serial" as the
4414 device type instead of "/dev/ttyXX". See mpw-README in the main
4415 directory for more information on how to build. The MPW configuration
4416 scripts */mpw-config.in support only a few targets, and only the
4417 mips-idt-ecoff target has been tested.
4421 GDB configuration now uses autoconf. This is not user-visible,
4422 but does simplify configuration and building.
4426 GDB now supports hpux10.
4428 *** Changes in GDB-4.14:
4430 * New native configurations
4432 x86 FreeBSD i[345]86-*-freebsd
4433 x86 NetBSD i[345]86-*-netbsd
4434 NS32k NetBSD ns32k-*-netbsd
4435 Sparc NetBSD sparc-*-netbsd
4439 A29K VxWorks a29k-*-vxworks
4440 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4441 CPU32 EST-300 emulator m68*-*-est*
4442 PowerPC ELF powerpc-*-elf
4445 * Alpha OSF/1 support for procfs
4447 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4448 possible to attach to running processes. As the mounting of the /proc
4449 filesystem is optional on the Alpha, GDB automatically determines
4450 the availability of /proc during startup. This can lead to problems
4451 if /proc is unmounted after GDB has been started.
4453 * Arguments to user-defined commands
4455 User commands may accept up to 10 arguments separated by whitespace.
4456 Arguments are accessed within the user command via $arg0..$arg9. A
4459 print $arg0 + $arg1 + $arg2
4461 To execute the command use:
4464 Defines the command "adder" which prints the sum of its three arguments.
4465 Note the arguments are text substitutions, so they may reference variables,
4466 use complex expressions, or even perform inferior function calls.
4468 * New `if' and `while' commands
4470 This makes it possible to write more sophisticated user-defined
4471 commands. Both commands take a single argument, which is the
4472 expression to evaluate, and must be followed by the commands to
4473 execute, one per line, if the expression is nonzero, the list being
4474 terminated by the word `end'. The `if' command list may include an
4475 `else' word, which causes the following commands to be executed only
4476 if the expression is zero.
4478 * Fortran source language mode
4480 GDB now includes partial support for Fortran 77. It will recognize
4481 Fortran programs and can evaluate a subset of Fortran expressions, but
4482 variables and functions may not be handled correctly. GDB will work
4483 with G77, but does not yet know much about symbols emitted by other
4486 * Better HPUX support
4488 Most debugging facilities now work on dynamic executables for HPPAs
4489 running hpux9 or later. You can attach to running dynamically linked
4490 processes, but by default the dynamic libraries will be read-only, so
4491 for instance you won't be able to put breakpoints in them. To change
4492 that behavior do the following before running the program:
4498 This will cause the libraries to be mapped private and read-write.
4499 To revert to the normal behavior, do this:
4505 You cannot set breakpoints or examine data in the library until after
4506 the library is loaded if the function/data symbols do not have
4509 GDB can now also read debug symbols produced by the HP C compiler on
4510 HPPAs (sorry, no C++, Fortran or 68k support).
4512 * Target byte order now dynamically selectable
4514 You can choose which byte order to use with a target system, via the
4515 commands "set endian big" and "set endian little", and you can see the
4516 current setting by using "show endian". You can also give the command
4517 "set endian auto", in which case GDB will use the byte order
4518 associated with the executable. Currently, only embedded MIPS
4519 configurations support dynamic selection of target byte order.
4521 * New DOS host serial code
4523 This version uses DPMI interrupts to handle buffered I/O, so you
4524 no longer need to run asynctsr when debugging boards connected to
4527 *** Changes in GDB-4.13:
4529 * New "complete" command
4531 This lists all the possible completions for the rest of the line, if it
4532 were to be given as a command itself. This is intended for use by emacs.
4534 * Trailing space optional in prompt
4536 "set prompt" no longer adds a space for you after the prompt you set. This
4537 allows you to set a prompt which ends in a space or one that does not.
4539 * Breakpoint hit counts
4541 "info break" now displays a count of the number of times the breakpoint
4542 has been hit. This is especially useful in conjunction with "ignore"; you
4543 can ignore a large number of breakpoint hits, look at the breakpoint info
4544 to see how many times the breakpoint was hit, then run again, ignoring one
4545 less than that number, and this will get you quickly to the last hit of
4548 * Ability to stop printing at NULL character
4550 "set print null-stop" will cause GDB to stop printing the characters of
4551 an array when the first NULL is encountered. This is useful when large
4552 arrays actually contain only short strings.
4554 * Shared library breakpoints
4556 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4557 breakpoints in shared libraries before the executable is run.
4559 * Hardware watchpoints
4561 There is a new hardware breakpoint for the watch command for sparclite
4562 targets. See gdb/sparclite/hw_breakpoint.note.
4564 Hardware watchpoints are also now supported under GNU/Linux.
4568 Annotations have been added. These are for use with graphical interfaces,
4569 and are still experimental. Currently only gdba.el uses these.
4571 * Improved Irix 5 support
4573 GDB now works properly with Irix 5.2.
4575 * Improved HPPA support
4577 GDB now works properly with the latest GCC and GAS.
4579 * New native configurations
4581 Sequent PTX4 i[34]86-sequent-ptx4
4582 HPPA running OSF/1 hppa*-*-osf*
4583 Atari TT running SVR4 m68*-*-sysv4*
4584 RS/6000 LynxOS rs6000-*-lynxos*
4588 OS/9000 i[34]86-*-os9k
4589 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4592 * Hitachi SH7000 and E7000-PC ICE support
4594 There is now support for communicating with the Hitachi E7000-PC ICE.
4595 This is available automatically when GDB is configured for the SH.
4599 As usual, a variety of small fixes and improvements, both generic
4600 and configuration-specific. See the ChangeLog for more detail.
4602 *** Changes in GDB-4.12:
4604 * Irix 5 is now supported
4608 GDB-4.12 on the HPPA has a number of changes which make it unable
4609 to debug the output from the currently released versions of GCC and
4610 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4611 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4612 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4615 *** Changes in GDB-4.11:
4617 * User visible changes:
4621 The "set remotedebug" option is now consistent between the mips remote
4622 target, remote targets using the gdb-specific protocol, UDI (AMD's
4623 debug protocol for the 29k) and the 88k bug monitor. It is now an
4624 integer specifying a debug level (normally 0 or 1, but 2 means more
4625 debugging info for the mips target).
4627 * DEC Alpha native support
4629 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4630 debug info, but GDB works fairly well with the DEC compiler and should
4631 work with a future GCC release. See the README file for a few
4632 Alpha-specific notes.
4634 * Preliminary thread implementation
4636 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4638 * LynxOS native and target support for 386
4640 This release has been hosted on LynxOS 2.2, and also can be configured
4641 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4644 * Improvements in C++ mangling/demangling.
4646 This release has much better g++ debugging, specifically in name
4647 mangling/demangling, virtual function calls, print virtual table,
4648 call methods, ...etc.
4650 *** Changes in GDB-4.10:
4652 * User visible changes:
4654 Remote debugging using the GDB-specific (`target remote') protocol now
4655 supports the `load' command. This is only useful if you have some
4656 other way of getting the stub to the target system, and you can put it
4657 somewhere in memory where it won't get clobbered by the download.
4659 Filename completion now works.
4661 When run under emacs mode, the "info line" command now causes the
4662 arrow to point to the line specified. Also, "info line" prints
4663 addresses in symbolic form (as well as hex).
4665 All vxworks based targets now support a user settable option, called
4666 vxworks-timeout. This option represents the number of seconds gdb
4667 should wait for responses to rpc's. You might want to use this if
4668 your vxworks target is, perhaps, a slow software simulator or happens
4669 to be on the far side of a thin network line.
4673 This release contains support for using a DEC alpha as a GDB host for
4674 cross debugging. Native alpha debugging is not supported yet.
4677 *** Changes in GDB-4.9:
4681 This is the first GDB release which is accompanied by a matching testsuite.
4682 The testsuite requires installation of dejagnu, which should be available
4683 via ftp from most sites that carry GNU software.
4687 'Cfront' style demangling has had its name changed to 'ARM' style, to
4688 emphasize that it was written from the specifications in the C++ Annotated
4689 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4690 disclaimers, it still generated too much confusion with users attempting to
4691 use gdb with AT&T cfront.
4695 GDB now uses a standard remote interface to a simulator library.
4696 So far, the library contains simulators for the Zilog Z8001/2, the
4697 Hitachi H8/300, H8/500 and Super-H.
4699 * New targets supported
4701 H8/300 simulator h8300-hitachi-hms or h8300hms
4702 H8/500 simulator h8500-hitachi-hms or h8500hms
4703 SH simulator sh-hitachi-hms or sh
4704 Z8000 simulator z8k-zilog-none or z8ksim
4705 IDT MIPS board over serial line mips-idt-ecoff
4707 Cross-debugging to GO32 targets is supported. It requires a custom
4708 version of the i386-stub.c module which is integrated with the
4709 GO32 memory extender.
4711 * New remote protocols
4713 MIPS remote debugging protocol.
4715 * New source languages supported
4717 This version includes preliminary support for Chill, a Pascal like language
4718 used by telecommunications companies. Chill support is also being integrated
4719 into the GNU compiler, but we don't know when it will be publically available.
4722 *** Changes in GDB-4.8:
4724 * HP Precision Architecture supported
4726 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4727 version of this support was available as a set of patches from the
4728 University of Utah. GDB does not support debugging of programs
4729 compiled with the HP compiler, because HP will not document their file
4730 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4731 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4733 Many problems in the preliminary version have been fixed.
4735 * Faster and better demangling
4737 We have improved template demangling and fixed numerous bugs in the GNU style
4738 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4739 character types (wchar_t) are now supported. Demangling of each symbol is now
4740 only done once, and is cached when the symbol table for a file is read in.
4741 This results in a small increase in memory usage for C programs, a moderate
4742 increase in memory usage for C++ programs, and a fantastic speedup in
4745 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4746 from the specifications in the Annotated Reference Manual, which AT&T's
4747 compiler does not actually implement.
4749 * G++ multiple inheritance compiler problem
4751 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4752 inheritance lattices was reworked to properly discover ambiguities. We
4753 recently found an example which causes this new algorithm to fail in a
4754 very subtle way, producing bad debug information for those classes.
4755 The file 'gcc.patch' (in this directory) can be applied to gcc to
4756 circumvent the problem. A future GCC release will contain a complete
4759 The previous G++ debug info problem (mentioned below for the gdb-4.7
4760 release) is fixed in gcc version 2.3.2.
4762 * Improved configure script
4764 The `configure' script will now attempt to guess your system type if
4765 you don't supply a host system type. The old scheme of supplying a
4766 host system triplet is preferable over using this. All the magic is
4767 done in the new `config.guess' script. Examine it for details.
4769 We have also brought our configure script much more in line with the FSF's
4770 version. It now supports the --with-xxx options. In particular,
4771 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4772 The resulting GDB will not be able to read arbitrary object file formats --
4773 only the format ``expected'' to be used on the configured target system.
4774 We hope to make this the default in a future release.
4776 * Documentation improvements
4778 There's new internal documentation on how to modify GDB, and how to
4779 produce clean changes to the code. We implore people to read it
4780 before submitting changes.
4782 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4783 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4784 `info' files are also provided. To build `info' files from scratch,
4785 you will need the latest `makeinfo' release, which will be available in
4786 a future texinfo-X.Y release.
4788 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4789 We're not sure exactly which versions have this problem, but it has
4790 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4791 or better. If that isn't possible, there is a patch in
4792 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4793 around this problem.
4797 GDB now supports array constants that can be used in expressions typed in by
4798 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4799 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4802 The new directory `gdb/sparclite' contains a program that demonstrates
4803 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4805 * New native hosts supported
4807 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4808 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4810 * New targets supported
4812 AMD 29k family via UDI a29k-amd-udi or udi29k
4814 * New file formats supported
4816 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4817 HPUX core files, and SCO 3.2v2 core files.
4821 Attaching to processes now works again; thanks for the many bug reports.
4823 We have also stomped on a bunch of core dumps caused by
4824 printf_filtered("%s") problems.
4826 We eliminated a copyright problem on the rpc and ptrace header files
4827 for VxWorks, which was discovered at the last minute during the 4.7
4828 release. You should now be able to build a VxWorks GDB.
4830 You can now interrupt gdb while an attached process is running. This
4831 will cause the attached process to stop, and give control back to GDB.
4833 We fixed problems caused by using too many file descriptors
4834 for reading symbols from object files and libraries. This was
4835 especially a problem for programs that used many (~100) shared
4838 The `step' command now only enters a subroutine if there is line number
4839 information for the subroutine. Otherwise it acts like the `next'
4840 command. Previously, `step' would enter subroutines if there was
4841 any debugging information about the routine. This avoids problems
4842 when using `cc -g1' on MIPS machines.
4844 * Internal improvements
4846 GDB's internal interfaces have been improved to make it easier to support
4847 debugging of multiple languages in the future.
4849 GDB now uses a common structure for symbol information internally.
4850 Minimal symbols (derived from linkage symbols in object files), partial
4851 symbols (from a quick scan of debug information), and full symbols
4852 contain a common subset of information, making it easier to write
4853 shared code that handles any of them.
4855 * New command line options
4857 We now accept --silent as an alias for --quiet.
4861 The memory-mapped-malloc library is now licensed under the GNU Library
4862 General Public License.
4864 *** Changes in GDB-4.7:
4866 * Host/native/target split
4868 GDB has had some major internal surgery to untangle the support for
4869 hosts and remote targets. Now, when you configure GDB for a remote
4870 target, it will no longer load in all of the support for debugging
4871 local programs on the host. When fully completed and tested, this will
4872 ensure that arbitrary host/target combinations are possible.
4874 The primary conceptual shift is to separate the non-portable code in
4875 GDB into three categories. Host specific code is required any time GDB
4876 is compiled on that host, regardless of the target. Target specific
4877 code relates to the peculiarities of the target, but can be compiled on
4878 any host. Native specific code is everything else: it can only be
4879 built when the host and target are the same system. Child process
4880 handling and core file support are two common `native' examples.
4882 GDB's use of /proc for controlling Unix child processes is now cleaner.
4883 It has been split out into a single module under the `target_ops' vector,
4884 plus two native-dependent functions for each system that uses /proc.
4886 * New hosts supported
4888 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4889 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4890 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4892 * New targets supported
4894 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4895 68030 and CPU32 m68030-*-*, m68332-*-*
4897 * New native hosts supported
4899 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4900 (386bsd is not well tested yet)
4901 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4903 * New file formats supported
4905 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4906 supports reading of `a.out.adobe' object files, which are an a.out
4907 format extended with minimal information about multiple sections.
4911 `show copying' is the same as the old `info copying'.
4912 `show warranty' is the same as `info warrantee'.
4913 These were renamed for consistency. The old commands continue to work.
4915 `info handle' is a new alias for `info signals'.
4917 You can now define pre-command hooks, which attach arbitrary command
4918 scripts to any command. The commands in the hook will be executed
4919 prior to the user's command. You can also create a hook which will be
4920 executed whenever the program stops. See gdb.texinfo.
4924 We now deal with Cfront style name mangling, and can even extract type
4925 info from mangled symbols. GDB can automatically figure out which
4926 symbol mangling style your C++ compiler uses.
4928 Calling of methods and virtual functions has been improved as well.
4932 The crash that occured when debugging Sun Ansi-C compiled binaries is
4933 fixed. This was due to mishandling of the extra N_SO stabs output
4936 We also finally got Ultrix 4.2 running in house, and fixed core file
4937 support, with help from a dozen people on the net.
4939 John M. Farrell discovered that the reason that single-stepping was so
4940 slow on all of the Mips based platforms (primarily SGI and DEC) was
4941 that we were trying to demangle and lookup a symbol used for internal
4942 purposes on every instruction that was being stepped through. Changing
4943 the name of that symbol so that it couldn't be mistaken for a C++
4944 mangled symbol sped things up a great deal.
4946 Rich Pixley sped up symbol lookups in general by getting much smarter
4947 about when C++ symbol mangling is necessary. This should make symbol
4948 completion (TAB on the command line) much faster. It's not as fast as
4949 we'd like, but it's significantly faster than gdb-4.6.
4953 A new user controllable variable 'call_scratch_address' can
4954 specify the location of a scratch area to be used when GDB
4955 calls a function in the target. This is necessary because the
4956 usual method of putting the scratch area on the stack does not work
4957 in systems that have separate instruction and data spaces.
4959 We integrated changes to support the 29k UDI (Universal Debugger
4960 Interface), but discovered at the last minute that we didn't have all
4961 of the appropriate copyright paperwork. We are working with AMD to
4962 resolve this, and hope to have it available soon.
4966 We have sped up the remote serial line protocol, especially for targets
4967 with lots of registers. It now supports a new `expedited status' ('T')
4968 message which can be used in place of the existing 'S' status message.
4969 This allows the remote stub to send only the registers that GDB
4970 needs to make a quick decision about single-stepping or conditional
4971 breakpoints, eliminating the need to fetch the entire register set for
4972 each instruction being stepped through.
4974 The GDB remote serial protocol now implements a write-through cache for
4975 registers, only re-reading the registers if the target has run.
4977 There is also a new remote serial stub for SPARC processors. You can
4978 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4979 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4980 processor with a serial port.
4984 Configure.in files have become much easier to read and modify. A new
4985 `table driven' format makes it more obvious what configurations are
4986 supported, and what files each one uses.
4990 There is a new opcodes library which will eventually contain all of the
4991 disassembly routines and opcode tables. At present, it only contains
4992 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4993 disassembler (binutils/objdump) to share these routines.
4995 The libiberty library is now copylefted under the GNU Library General
4996 Public License. This allows more liberal use, and was done so libg++
4997 can use it. This makes no difference to GDB, since the Library License
4998 grants all the rights from the General Public License.
5002 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5003 reference to the stabs symbol info used by the debugger. It is (as far
5004 as we know) the only published document on this fascinating topic. We
5005 encourage you to read it, compare it to the stabs information on your
5006 system, and send improvements on the document in general (to
5007 bug-gdb@prep.ai.mit.edu).
5009 And, of course, many bugs have been fixed.
5012 *** Changes in GDB-4.6:
5014 * Better support for C++ function names
5016 GDB now accepts as input the "demangled form" of C++ overloaded function
5017 names and member function names, and can do command completion on such names
5018 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5019 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5020 Make use of command completion, it is your friend.
5022 GDB also now accepts a variety of C++ mangled symbol formats. They are
5023 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5024 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5025 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5026 for the list of formats.
5028 * G++ symbol mangling problem
5030 Recent versions of gcc have a bug in how they emit debugging information for
5031 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5032 directory) can be applied to gcc to fix the problem. Alternatively, if you
5033 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5034 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5035 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5038 * New 'maintenance' command
5040 All of the commands related to hacking GDB internals have been moved out of
5041 the main command set, and now live behind the 'maintenance' command. This
5042 can also be abbreviated as 'mt'. The following changes were made:
5044 dump-me -> maintenance dump-me
5045 info all-breakpoints -> maintenance info breakpoints
5046 printmsyms -> maintenance print msyms
5047 printobjfiles -> maintenance print objfiles
5048 printpsyms -> maintenance print psymbols
5049 printsyms -> maintenance print symbols
5051 The following commands are new:
5053 maintenance demangle Call internal GDB demangler routine to
5054 demangle a C++ link name and prints the result.
5055 maintenance print type Print a type chain for a given symbol
5057 * Change to .gdbinit file processing
5059 We now read the $HOME/.gdbinit file before processing the argv arguments
5060 (e.g. reading symbol files or core files). This allows global parameters to
5061 be set, which will apply during the symbol reading. The ./.gdbinit is still
5062 read after argv processing.
5064 * New hosts supported
5066 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5068 GNU/Linux support i386-unknown-linux or linux
5070 We are also including code to support the HP/PA running BSD and HPUX. This
5071 is almost guaranteed not to work, as we didn't have time to test or build it
5072 for this release. We are including it so that the more adventurous (or
5073 masochistic) of you can play with it. We also had major problems with the
5074 fact that the compiler that we got from HP doesn't support the -g option.
5077 * New targets supported
5079 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5081 * More smarts about finding #include files
5083 GDB now remembers the compilation directory for all include files, and for
5084 all files from which C is generated (like yacc and lex sources). This
5085 greatly improves GDB's ability to find yacc/lex sources, and include files,
5086 especially if you are debugging your program from a directory different from
5087 the one that contains your sources.
5089 We also fixed a bug which caused difficulty with listing and setting
5090 breakpoints in include files which contain C code. (In the past, you had to
5091 try twice in order to list an include file that you hadn't looked at before.)
5093 * Interesting infernals change
5095 GDB now deals with arbitrary numbers of sections, where the symbols for each
5096 section must be relocated relative to that section's landing place in the
5097 target's address space. This work was needed to support ELF with embedded
5098 stabs used by Solaris-2.0.
5100 * Bug fixes (of course!)
5102 There have been loads of fixes for the following things:
5103 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5104 i960, stabs, DOS(GO32), procfs, etc...
5106 See the ChangeLog for details.
5108 *** Changes in GDB-4.5:
5110 * New machines supported (host and target)
5112 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5114 SGI Irix-4.x mips-sgi-irix4 or iris4
5116 * New malloc package
5118 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5119 Mmalloc is capable of handling mutiple heaps of memory. It is also
5120 capable of saving a heap to a file, and then mapping it back in later.
5121 This can be used to greatly speedup the startup of GDB by using a
5122 pre-parsed symbol table which lives in a mmalloc managed heap. For
5123 more details, please read mmalloc/mmalloc.texi.
5127 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5128 'help info proc' for details.
5130 * MIPS ecoff symbol table format
5132 The code that reads MIPS symbol table format is now supported on all hosts.
5133 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5136 * File name changes for MS-DOS
5138 Many files in the config directories have been renamed to make it easier to
5139 support GDB on MS-DOSe systems (which have very restrictive file name
5140 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5141 environment) is close to working but has some remaining problems. Note
5142 that debugging of DOS programs is not supported, due to limitations
5143 in the ``operating system'', but it can be used to host cross-debugging.
5145 * Cross byte order fixes
5147 Many fixes have been made to support cross debugging of Sparc and MIPS
5148 targets from hosts whose byte order differs.
5150 * New -mapped and -readnow options
5152 If memory-mapped files are available on your system through the 'mmap'
5153 system call, you can use the -mapped option on the `file' or
5154 `symbol-file' commands to cause GDB to write the symbols from your
5155 program into a reusable file. If the program you are debugging is
5156 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5157 Future GDB debugging sessions will notice the presence of this file,
5158 and will quickly map in symbol information from it, rather than reading
5159 the symbol table from the executable program. Using the '-mapped'
5160 option in a GDB `file' or `symbol-file' command has the same effect as
5161 starting GDB with the '-mapped' command-line option.
5163 You can cause GDB to read the entire symbol table immediately by using
5164 the '-readnow' option with any of the commands that load symbol table
5165 information (or on the GDB command line). This makes the command
5166 slower, but makes future operations faster.
5168 The -mapped and -readnow options are typically combined in order to
5169 build a `fred.syms' file that contains complete symbol information.
5170 A simple GDB invocation to do nothing but build a `.syms' file for future
5173 gdb -batch -nx -mapped -readnow programname
5175 The `.syms' file is specific to the host machine on which GDB is run.
5176 It holds an exact image of GDB's internal symbol table. It cannot be
5177 shared across multiple host platforms.
5179 * longjmp() handling
5181 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5182 siglongjmp() without losing control. This feature has not yet been ported to
5183 all systems. It currently works on many 386 platforms, all MIPS-based
5184 platforms (SGI, DECstation, etc), and Sun3/4.
5188 Preliminary work has been put in to support the new Solaris OS from Sun. At
5189 this time, it can control and debug processes, but it is not capable of
5194 As always, many many bug fixes. The major areas were with g++, and mipsread.
5195 People using the MIPS-based platforms should experience fewer mysterious
5196 crashes and trashed symbol tables.
5198 *** Changes in GDB-4.4:
5200 * New machines supported (host and target)
5202 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5204 BSD Reno on Vax vax-dec-bsd
5205 Ultrix on Vax vax-dec-ultrix
5207 * New machines supported (target)
5209 AMD 29000 embedded, using EBMON a29k-none-none
5213 GDB continues to improve its handling of C++. `References' work better.
5214 The demangler has also been improved, and now deals with symbols mangled as
5215 per the Annotated C++ Reference Guide.
5217 GDB also now handles `stabs' symbol information embedded in MIPS
5218 `ecoff' symbol tables. Since the ecoff format was not easily
5219 extensible to handle new languages such as C++, this appeared to be a
5220 good way to put C++ debugging info into MIPS binaries. This option
5221 will be supported in the GNU C compiler, version 2, when it is
5224 * New features for SVR4
5226 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5227 shared libraries. Debugging dynamically linked programs should present
5228 only minor differences from debugging statically linked programs.
5230 The `info proc' command will print out information about any process
5231 on an SVR4 system (including the one you are debugging). At the moment,
5232 it prints the address mappings of the process.
5234 If you bring up GDB on another SVR4 system, please send mail to
5235 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5237 * Better dynamic linking support in SunOS
5239 Reading symbols from shared libraries which contain debugging symbols
5240 now works properly. However, there remain issues such as automatic
5241 skipping of `transfer vector' code during function calls, which
5242 make it harder to debug code in a shared library, than to debug the
5243 same code linked statically.
5247 GDB is now using the latest `getopt' routines from the FSF. This
5248 version accepts the -- prefix for options with long names. GDB will
5249 continue to accept the old forms (-option and +option) as well.
5250 Various single letter abbreviations for options have been explicity
5251 added to the option table so that they won't get overshadowed in the
5252 future by other options that begin with the same letter.
5256 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5257 Many assorted bugs have been handled. Many more remain to be handled.
5258 See the various ChangeLog files (primarily in gdb and bfd) for details.
5261 *** Changes in GDB-4.3:
5263 * New machines supported (host and target)
5265 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5266 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5267 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5269 * Almost SCO Unix support
5271 We had hoped to support:
5272 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5273 (except for core file support), but we discovered very late in the release
5274 that it has problems with process groups that render gdb unusable. Sorry
5275 about that. I encourage people to fix it and post the fixes.
5277 * Preliminary ELF and DWARF support
5279 GDB can read ELF object files on System V Release 4, and can handle
5280 debugging records for C, in DWARF format, in ELF files. This support
5281 is preliminary. If you bring up GDB on another SVR4 system, please
5282 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5287 GDB now uses the latest `readline' library. One user-visible change
5288 is that two tabs will list possible command completions, which previously
5289 required typing M-? (meta-question mark, or ESC ?).
5293 The `stepi' bug that many of you noticed has been squashed.
5294 Many bugs in C++ have been handled. Many more remain to be handled.
5295 See the various ChangeLog files (primarily in gdb and bfd) for details.
5297 * State of the MIPS world (in case you wondered):
5299 GDB can understand the symbol tables emitted by the compilers
5300 supplied by most vendors of MIPS-based machines, including DEC. These
5301 symbol tables are in a format that essentially nobody else uses.
5303 Some versions of gcc come with an assembler post-processor called
5304 mips-tfile. This program is required if you want to do source-level
5305 debugging of gcc-compiled programs. I believe FSF does not ship
5306 mips-tfile with gcc version 1, but it will eventually come with gcc
5309 Debugging of g++ output remains a problem. g++ version 1.xx does not
5310 really support it at all. (If you're lucky, you should be able to get
5311 line numbers and stack traces to work, but no parameters or local
5312 variables.) With some work it should be possible to improve the
5315 When gcc version 2 is released, you will have somewhat better luck.
5316 However, even then you will get confusing results for inheritance and
5319 We will eventually provide full debugging of g++ output on
5320 DECstations. This will probably involve some kind of stabs-in-ecoff
5321 encapulation, but the details have not been worked out yet.
5324 *** Changes in GDB-4.2:
5326 * Improved configuration
5328 Only one copy of `configure' exists now, and it is not self-modifying.
5329 Porting BFD is simpler.
5333 The `step' and `next' commands now only stop at the first instruction
5334 of a source line. This prevents the multiple stops that used to occur
5335 in switch statements, for-loops, etc. `Step' continues to stop if a
5336 function that has debugging information is called within the line.
5340 Lots of small bugs fixed. More remain.
5342 * New host supported (not target)
5344 Intel 386 PC clone running Mach i386-none-mach
5347 *** Changes in GDB-4.1:
5349 * Multiple source language support
5351 GDB now has internal scaffolding to handle several source languages.
5352 It determines the type of each source file from its filename extension,
5353 and will switch expression parsing and number formatting to match the
5354 language of the function in the currently selected stack frame.
5355 You can also specifically set the language to be used, with
5356 `set language c' or `set language modula-2'.
5360 GDB now has preliminary support for the GNU Modula-2 compiler,
5361 currently under development at the State University of New York at
5362 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5363 continue through the fall of 1991 and into 1992.
5365 Other Modula-2 compilers are currently not supported, and attempting to
5366 debug programs compiled with them will likely result in an error as the
5367 symbol table is read. Feel free to work on it, though!
5369 There are hooks in GDB for strict type checking and range checking,
5370 in the `Modula-2 philosophy', but they do not currently work.
5374 GDB can now write to executable and core files (e.g. patch
5375 a variable's value). You must turn this switch on, specify
5376 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5377 by assigning a new value to a variable. Modifications take
5380 * Automatic SunOS shared library reading
5382 When you run your program, GDB automatically determines where its
5383 shared libraries (if any) have been loaded, and reads their symbols.
5384 The `share' command is no longer needed. This also works when
5385 examining core files.
5389 You can specify the number of lines that the `list' command shows.
5392 * New machines supported (host and target)
5394 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5395 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5396 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5398 * New hosts supported (not targets)
5400 IBM RT/PC: romp-ibm-aix or rtpc
5402 * New targets supported (not hosts)
5404 AMD 29000 embedded with COFF a29k-none-coff
5405 AMD 29000 embedded with a.out a29k-none-aout
5406 Ultracomputer remote kernel debug a29k-nyu-kern
5408 * New remote interfaces
5414 *** Changes in GDB-4.0:
5418 Wide output is wrapped at good places to make the output more readable.
5420 Gdb now supports cross-debugging from a host machine of one type to a
5421 target machine of another type. Communication with the target system
5422 is over serial lines. The ``target'' command handles connecting to the
5423 remote system; the ``load'' command will download a program into the
5424 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5425 also supports debugging of realtime processes running under VxWorks,
5426 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5427 stub on the target system.
5429 New CPUs supported include the AMD 29000 and Intel 960.
5431 GDB now reads object files and symbol tables via a ``binary file''
5432 library, which allows a single copy of GDB to debug programs of multiple
5433 object file types such as a.out and coff.
5435 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5436 refcard.dvi and refcard.ps are available to format it).
5439 * Control-Variable user interface simplified
5441 All variables that control the operation of the debugger can be set
5442 by the ``set'' command, and displayed by the ``show'' command.
5444 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5445 ``Show prompt'' produces the response:
5446 Gdb's prompt is new-gdb=>.
5448 What follows are the NEW set commands. The command ``help set'' will
5449 print a complete list of old and new set commands. ``help set FOO''
5450 will give a longer description of the variable FOO. ``show'' will show
5451 all of the variable descriptions and their current settings.
5453 confirm on/off: Enables warning questions for operations that are
5454 hard to recover from, e.g. rerunning the program while
5455 it is already running. Default is ON.
5457 editing on/off: Enables EMACS style command line editing
5458 of input. Previous lines can be recalled with
5459 control-P, the current line can be edited with control-B,
5460 you can search for commands with control-R, etc.
5463 history filename NAME: NAME is where the gdb command history
5464 will be stored. The default is .gdb_history,
5465 or the value of the environment variable
5468 history size N: The size, in commands, of the command history. The
5469 default is 256, or the value of the environment variable
5472 history save on/off: If this value is set to ON, the history file will
5473 be saved after exiting gdb. If set to OFF, the
5474 file will not be saved. The default is OFF.
5476 history expansion on/off: If this value is set to ON, then csh-like
5477 history expansion will be performed on
5478 command line input. The default is OFF.
5480 radix N: Sets the default radix for input and output. It can be set
5481 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5482 in the current radix, so "set radix 10" is always a no-op.
5484 height N: This integer value is the number of lines on a page. Default
5485 is 24, the current `stty rows'' setting, or the ``li#''
5486 setting from the termcap entry matching the environment
5489 width N: This integer value is the number of characters on a line.
5490 Default is 80, the current `stty cols'' setting, or the ``co#''
5491 setting from the termcap entry matching the environment
5494 Note: ``set screensize'' is obsolete. Use ``set height'' and
5495 ``set width'' instead.
5497 print address on/off: Print memory addresses in various command displays,
5498 such as stack traces and structure values. Gdb looks
5499 more ``symbolic'' if you turn this off; it looks more
5500 ``machine level'' with it on. Default is ON.
5502 print array on/off: Prettyprint arrays. New convenient format! Default
5505 print demangle on/off: Print C++ symbols in "source" form if on,
5508 print asm-demangle on/off: Same, for assembler level printouts
5511 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5514 * Support for Epoch Environment.
5516 The epoch environment is a version of Emacs v18 with windowing. One
5517 new command, ``inspect'', is identical to ``print'', except that if you
5518 are running in the epoch environment, the value is printed in its own
5522 * Support for Shared Libraries
5524 GDB can now debug programs and core files that use SunOS shared libraries.
5525 Symbols from a shared library cannot be referenced
5526 before the shared library has been linked with the program (this
5527 happens after you type ``run'' and before the function main() is entered).
5528 At any time after this linking (including when examining core files
5529 from dynamically linked programs), gdb reads the symbols from each
5530 shared library when you type the ``sharedlibrary'' command.
5531 It can be abbreviated ``share''.
5533 sharedlibrary REGEXP: Load shared object library symbols for files
5534 matching a unix regular expression. No argument
5535 indicates to load symbols for all shared libraries.
5537 info sharedlibrary: Status of loaded shared libraries.
5542 A watchpoint stops execution of a program whenever the value of an
5543 expression changes. Checking for this slows down execution
5544 tremendously whenever you are in the scope of the expression, but is
5545 quite useful for catching tough ``bit-spreader'' or pointer misuse
5546 problems. Some machines such as the 386 have hardware for doing this
5547 more quickly, and future versions of gdb will use this hardware.
5549 watch EXP: Set a watchpoint (breakpoint) for an expression.
5551 info watchpoints: Information about your watchpoints.
5553 delete N: Deletes watchpoint number N (same as breakpoints).
5554 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5555 enable N: Re-enables watchpoint number N (same as breakpoints).
5558 * C++ multiple inheritance
5560 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5563 * C++ exception handling
5565 Gdb now supports limited C++ exception handling. Besides the existing
5566 ability to breakpoint on an exception handler, gdb can breakpoint on
5567 the raising of an exception (before the stack is peeled back to the
5570 catch FOO: If there is a FOO exception handler in the dynamic scope,
5571 set a breakpoint to catch exceptions which may be raised there.
5572 Multiple exceptions (``catch foo bar baz'') may be caught.
5574 info catch: Lists all exceptions which may be caught in the
5575 current stack frame.
5578 * Minor command changes
5580 The command ``call func (arg, arg, ...)'' now acts like the print
5581 command, except it does not print or save a value if the function's result
5582 is void. This is similar to dbx usage.
5584 The ``up'' and ``down'' commands now always print the frame they end up
5585 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5586 frames without printing.
5588 * New directory command
5590 'dir' now adds directories to the FRONT of the source search path.
5591 The path starts off empty. Source files that contain debug information
5592 about the directory in which they were compiled can be found even
5593 with an empty path; Sun CC and GCC include this information. If GDB can't
5594 find your source file in the current directory, type "dir .".
5596 * Configuring GDB for compilation
5598 For normal use, type ``./configure host''. See README or gdb.texinfo
5601 GDB now handles cross debugging. If you are remotely debugging between
5602 two different machines, type ``./configure host -target=targ''.
5603 Host is the machine where GDB will run; targ is the machine
5604 where the program that you are debugging will run.
5606 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.