1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.6
6 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
8 * GDB now supports Fission DWP file format version 2.
9 http://gcc.gnu.org/wiki/DebugFission
11 * New convenience function "$_isvoid", to check whether an expression
12 is void. A void expression is an expression where the type of the
13 result is "void". For example, some convenience variables may be
14 "void" when evaluated (e.g., "$_exitcode" before the execution of
15 the program being debugged; or an undefined convenience variable).
16 Another example, when calling a function whose return type is
19 * The "maintenance print objfiles" command now takes an optional regexp.
21 * The "catch syscall" command now works on arm*-linux* targets.
23 * GDB now consistently shows "<not saved>" when printing values of
24 registers the debug info indicates have not been saved in the frame
25 and there's nowhere to retrieve them from
26 (callee-saved/call-clobbered registers):
31 (gdb) info registers rax
34 Before, the former would print "<optimized out>", and the latter
35 "*value not available*".
37 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
42 ** Frame filters and frame decorators have been added.
43 ** Temporary breakpoints are now supported.
44 ** Line tables representation has been added.
45 ** New attribute 'parent_type' for gdb.Field objects.
46 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
50 Nios II ELF nios2*-*-elf
51 Nios II GNU/Linux nios2*-*-linux
52 Texas Instruments MSP430 msp430*-*-elf
54 * Removed native configurations
56 Support for these a.out NetBSD and OpenBSD obsolete configurations has
57 been removed. ELF variants of these configurations are kept supported.
59 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
60 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
61 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
62 i[34567]86-*-openbsd3.[0-3]
63 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
64 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
65 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
69 Like "catch throw", but catches a re-thrown exception.
71 Renamed from old "maint check-symtabs".
73 Perform consistency checks on symtabs.
75 Expand symtabs matching an optional regexp.
78 Display the details of GDB configure-time options.
80 maint set|show per-command
81 maint set|show per-command space
82 maint set|show per-command time
83 maint set|show per-command symtab
84 Enable display of per-command gdb resource usage.
86 remove-symbol-file FILENAME
87 remove-symbol-file -a ADDRESS
88 Remove a symbol file added via add-symbol-file. The file to remove
89 can be identified by its filename or by an address that lies within
90 the boundaries of this symbol file in memory.
93 info exceptions REGEXP
94 Display the list of Ada exceptions defined in the program being
95 debugged. If provided, only the exceptions whose names match REGEXP
100 set debug symfile off|on
102 Control display of debugging info regarding reading symbol files and
103 symbol tables within those files
105 set print raw frame-arguments
106 show print raw frame-arguments
107 Set/show whether to print frame arguments in raw mode,
108 disregarding any defined pretty-printers.
110 set remote trace-status-packet
111 show remote trace-status-packet
112 Set/show the use of remote protocol qTStatus packet.
116 Control display of debugging messages related to Nios II targets.
120 Control whether target-assisted range stepping is enabled.
122 set startup-with-shell
123 show startup-with-shell
124 Specifies whether Unix child processes are started via a shell or
129 Use the target memory cache for accesses to the code segment. This
130 improves performance of remote debugging (particularly disassembly).
132 * You can now use a literal value 'unlimited' for options that
133 interpret 0 or -1 as meaning "unlimited". E.g., "set
134 trace-buffer-size unlimited" is now an alias for "set
135 trace-buffer-size -1" and "set height unlimited" is now an alias for
138 * The "set debug symtab-create" debugging option of GDB has been changed to
139 accept a verbosity level. 0 means "off", 1 provides basic debugging
140 output, and values of 2 or greater provides more verbose output.
142 * New command-line options
144 Display the details of GDB configure-time options.
146 * The command 'tsave' can now support new option '-ctf' to save trace
147 buffer in Common Trace Format.
149 * Newly installed $prefix/bin/gcore acts as a shell interface for the
152 * GDB now implements the the C++ 'typeid' operator.
154 * The new convenience variable $_exception holds the exception being
155 thrown or caught at an exception-related catchpoint.
157 * The exception-related catchpoints, like "catch throw", now accept a
158 regular expression which can be used to filter exceptions by type.
160 * The new convenience variable $_exitsignal is automatically set to
161 the terminating signal number when the program being debugged dies
162 due to an uncaught signal.
166 ** All MI commands now accept an optional "--language" option.
167 Support for this feature can be verified by using the "-list-features"
168 command, which should contain "language-option".
170 ** The new command -info-gdb-mi-command allows the user to determine
171 whether a GDB/MI command is supported or not.
173 ** The "^error" result record returned when trying to execute an undefined
174 GDB/MI command now provides a variable named "code" whose content is the
175 "undefined-command" error code. Support for this feature can be verified
176 by using the "-list-features" command, which should contain
177 "undefined-command-error-code".
179 ** The -trace-save MI command can optionally save trace buffer in Common
182 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
184 ** The command -data-list-register-values now accepts an optional
185 "--skip-unavailable" option. When used, only the available registers
188 ** The new command -trace-frame-collected dumps collected variables,
189 computed expressions, tvars, memory and registers in a traceframe.
191 ** The commands -stack-list-locals, -stack-list-arguments and
192 -stack-list-variables now accept an option "--skip-unavailable".
193 When used, only the available locals or arguments are displayed.
195 ** The -exec-run command now accepts an optional "--start" option.
196 When used, the command follows the same semantics as the "start"
197 command, stopping the program's execution at the start of its
198 main subprogram. Support for this feature can be verified using
199 the "-list-features" command, which should contain
200 "exec-run-start-option".
202 ** The new commands -catch-assert and -catch-exceptions insert
203 catchpoints stopping the program when Ada exceptions are raised.
205 ** The new command -info-ada-exceptions provides the equivalent of
206 the new "info exceptions" command.
208 * New system-wide configuration scripts
209 A GDB installation now provides scripts suitable for use as system-wide
210 configuration scripts for the following systems:
214 * GDB now supports target-assigned range stepping with remote targets.
215 This improves the performance of stepping source lines by reducing
216 the number of control packets from/to GDB. See "New remote packets"
219 * GDB now understands the element 'tvar' in the XML traceframe info.
220 It has the id of the collected trace state variables.
222 * On S/390 targets that provide the transactional-execution feature,
223 the program interruption transaction diagnostic block (TDB) is now
224 represented as a number of additional "registers" in GDB.
230 The vCont packet supports a new 'r' action, that tells the remote
231 stub to step through an address range itself, without GDB
232 involvemement at each single-step.
234 qXfer:libraries-svr4:read's annex
235 The previously unused annex of the qXfer:libraries-svr4:read packet
236 is now used to support passing an argument list. The remote stub
237 reports support for this argument list to GDB's qSupported query.
238 The defined arguments are "start" and "prev", used to reduce work
239 necessary for library list updating, resulting in significant
242 * New features in the GDB remote stub, GDBserver
244 ** GDBserver now supports target-assisted range stepping. Currently
245 enabled on x86/x86_64 GNU/Linux targets.
247 ** GDBserver now adds element 'tvar' in the XML in the reply to
248 'qXfer:traceframe-info:read'. It has the id of the collected
249 trace state variables.
251 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
254 * New 'z' formatter for printing and examining memory, this displays the
255 value as hexadecimal zero padded on the left to the size of the type.
257 * GDB can now use Windows x64 unwinding data.
259 * The "set remotebaud" command has been replaced by "set serial baud".
260 Similarly, "show remotebaud" has been replaced by "show serial baud".
261 The "set remotebaud" and "show remotebaud" commands are still available
262 to provide backward compatibility with older versions of GDB.
264 *** Changes in GDB 7.6
266 * Target record has been renamed to record-full.
267 Record/replay is now enabled with the "record full" command.
268 This also affects settings that are associated with full record/replay
269 that have been moved from "set/show record" to "set/show record full":
271 set|show record full insn-number-max
272 set|show record full stop-at-limit
273 set|show record full memory-query
275 * A new record target "record-btrace" has been added. The new target
276 uses hardware support to record the control-flow of a process. It
277 does not support replaying the execution, but it implements the
278 below new commands for investigating the recorded execution log.
279 This new recording method can be enabled using:
283 The "record-btrace" target is only available on Intel Atom processors
284 and requires a Linux kernel 2.6.32 or later.
286 * Two new commands have been added for record/replay to give information
287 about the recorded execution without having to replay the execution.
288 The commands are only supported by "record btrace".
290 record instruction-history prints the execution history at
291 instruction granularity
293 record function-call-history prints the execution history at
296 * New native configurations
298 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
299 FreeBSD/powerpc powerpc*-*-freebsd
300 x86_64/Cygwin x86_64-*-cygwin*
301 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
305 ARM AArch64 aarch64*-*-elf
306 ARM AArch64 GNU/Linux aarch64*-*-linux
307 Lynx 178 PowerPC powerpc-*-lynx*178
308 x86_64/Cygwin x86_64-*-cygwin*
309 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
311 * If the configured location of system.gdbinit file (as given by the
312 --with-system-gdbinit option at configure time) is in the
313 data-directory (as specified by --with-gdb-datadir at configure
314 time) or in one of its subdirectories, then GDB will look for the
315 system-wide init file in the directory specified by the
316 --data-directory command-line option.
318 * New command line options:
320 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
321 other initialization files, unlike -nx which disables all of them.
323 * Removed command line options
325 -epoch This was used by the gdb mode in Epoch, an ancient fork of
328 * The 'ptype' and 'whatis' commands now accept an argument to control
331 * 'info proc' now works on some core files.
335 ** Vectors can be created with gdb.Type.vector.
337 ** Python's atexit.register now works in GDB.
339 ** Types can be pretty-printed via a Python API.
341 ** Python 3 is now supported (in addition to Python 2.4 or later)
343 ** New class gdb.Architecture exposes GDB's internal representation
344 of architecture in the Python API.
346 ** New method Frame.architecture returns the gdb.Architecture object
347 corresponding to the frame's architecture.
349 * New Python-based convenience functions:
351 ** $_memeq(buf1, buf2, length)
352 ** $_streq(str1, str2)
354 ** $_regex(str, regex)
356 * The 'cd' command now defaults to using '~' (the home directory) if not
359 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
360 default for GCC since November 2000.
362 * The command 'forward-search' can now be abbreviated as 'fo'.
364 * The command 'info tracepoints' can now display 'installed on target'
365 or 'not installed on target' for each non-pending location of tracepoint.
367 * New configure options
369 --enable-libmcheck/--disable-libmcheck
370 By default, development versions are built with -lmcheck on hosts
371 that support it, in order to help track memory corruption issues.
372 Release versions, on the other hand, are built without -lmcheck
373 by default. The --enable-libmcheck/--disable-libmcheck configure
374 options allow the user to override that default.
375 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
376 This configure option allows the user to build GDB with
377 libbabeltrace using which GDB can read Common Trace Format data.
379 * New commands (for set/show, see "New options" below)
382 Catch signals. This is similar to "handle", but allows commands and
383 conditions to be attached.
386 List the BFDs known to GDB.
388 python-interactive [command]
390 Start a Python interactive prompt, or evaluate the optional command
391 and print the result of expressions.
394 "py" is a new alias for "python".
396 enable type-printer [name]...
397 disable type-printer [name]...
398 Enable or disable type printers.
402 ** For the Renesas Super-H architecture, the "regs" command has been removed
403 (has been deprecated in GDB 7.5), and "info all-registers" should be used
408 set print type methods (on|off)
409 show print type methods
410 Control whether method declarations are displayed by "ptype".
411 The default is to show them.
413 set print type typedefs (on|off)
414 show print type typedefs
415 Control whether typedef definitions are displayed by "ptype".
416 The default is to show them.
418 set filename-display basename|relative|absolute
419 show filename-display
420 Control the way in which filenames is displayed.
421 The default is "relative", which preserves previous behavior.
423 set trace-buffer-size
424 show trace-buffer-size
425 Request target to change the size of trace buffer.
427 set remote trace-buffer-size-packet auto|on|off
428 show remote trace-buffer-size-packet
429 Control the use of the remote protocol `QTBuffer:size' packet.
433 Control display of debugging messages related to ARM AArch64.
436 set debug coff-pe-read
437 show debug coff-pe-read
438 Control display of debugging messages related to reading of COFF/PE
443 Control display of debugging messages related to Mach-O symbols
446 set debug notification
447 show debug notification
448 Control display of debugging info for async remote notification.
452 ** Command parameter changes are now notified using new async record
453 "=cmd-param-changed".
454 ** Trace frame changes caused by command "tfind" are now notified using
455 new async record "=traceframe-changed".
456 ** The creation, deletion and modification of trace state variables
457 are now notified using new async records "=tsv-created",
458 "=tsv-deleted" and "=tsv-modified".
459 ** The start and stop of process record are now notified using new
460 async record "=record-started" and "=record-stopped".
461 ** Memory changes are now notified using new async record
463 ** The data-disassemble command response will include a "fullname" field
464 containing the absolute file name when source has been requested.
465 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
466 command, to allow pattern filling of memory areas.
467 ** New commands "-catch-load"/"-catch-unload" added for intercepting
468 library load/unload events.
469 ** The response to breakpoint commands and breakpoint async records
470 includes an "installed" field containing a boolean state about each
471 non-pending tracepoint location is whether installed on target or not.
472 ** Output of the "-trace-status" command includes a "trace-file" field
473 containing the name of the trace file being examined. This field is
474 optional, and only present when examining a trace file.
475 ** The "fullname" field is now always present along with the "file" field,
476 even if the file cannot be found by GDB.
478 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
479 You must have the LZMA library available when configuring GDB for this
480 feature to be enabled. For more information, see:
481 http://fedoraproject.org/wiki/Features/MiniDebugInfo
486 Set the size of trace buffer. The remote stub reports support for this
487 packet to gdb's qSupported query.
490 Enable Branch Trace Store (BTS)-based branch tracing for the current
491 thread. The remote stub reports support for this packet to gdb's
495 Disable branch tracing for the current thread. The remote stub reports
496 support for this packet to gdb's qSupported query.
499 Read the traced branches for the current thread. The remote stub
500 reports support for this packet to gdb's qSupported query.
502 *** Changes in GDB 7.5
504 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
505 for more x32 ABI info.
507 * GDB now supports access to MIPS DSP registers on Linux targets.
509 * GDB now supports debugging microMIPS binaries.
511 * The "info os" command on GNU/Linux can now display information on
512 several new classes of objects managed by the operating system:
513 "info os procgroups" lists process groups
514 "info os files" lists file descriptors
515 "info os sockets" lists internet-domain sockets
516 "info os shm" lists shared-memory regions
517 "info os semaphores" lists semaphores
518 "info os msg" lists message queues
519 "info os modules" lists loaded kernel modules
521 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
522 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
523 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
524 options and inspect the probe arguments using the new $_probe_arg family
525 of convenience variables. You can obtain more information about SystemTap
526 in <http://sourceware.org/systemtap/>.
528 * GDB now supports reversible debugging on ARM, it allows you to
529 debug basic ARM and THUMB instructions, and provides
530 record/replay support.
532 * The option "symbol-reloading" has been deleted as it is no longer used.
536 ** GDB commands implemented in Python can now be put in command class
539 ** The "maint set python print-stack on|off" is now deleted.
541 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
542 apply "flag enum"-style pretty-printing to any enum.
544 ** gdb.lookup_symbol can now work when there is no current frame.
546 ** gdb.Symbol now has a 'line' attribute, holding the line number in
547 the source at which the symbol was defined.
549 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
550 method 'value'. The former indicates whether the symbol needs a
551 frame in order to compute its value, and the latter computes the
554 ** A new method 'referenced_value' on gdb.Value objects which can
555 dereference pointer as well as C++ reference values.
557 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
558 which return the global and static blocks (as gdb.Block objects),
559 of the underlying symbol table, respectively.
561 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
562 object associated with a PC value.
564 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
565 of the address range occupied by code for the current source line.
567 * Go language support.
568 GDB now supports debugging programs written in the Go programming
571 * GDBserver now supports stdio connections.
572 E.g. (gdb) target remote | ssh myhost gdbserver - hello
574 * The binary "gdbtui" can no longer be built or installed.
575 Use "gdb -tui" instead.
577 * GDB will now print "flag" enums specially. A flag enum is one where
578 all the enumerator values have no bits in common when pairwise
579 "and"ed. When printing a value whose type is a flag enum, GDB will
580 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
581 (gdb) print (enum E) 3
584 * The filename part of a linespec will now match trailing components
585 of a source file name. For example, "break gcc/expr.c:1000" will
586 now set a breakpoint in build/gcc/expr.c, but not
589 * The "info proc" and "generate-core-file" commands will now also
590 work on remote targets connected to GDBserver on Linux.
592 * The command "info catch" has been removed. It has been disabled
595 * The "catch exception" and "catch assert" commands now accept
596 a condition at the end of the command, much like the "break"
597 command does. For instance:
599 (gdb) catch exception Constraint_Error if Barrier = True
601 Previously, it was possible to add a condition to such catchpoints,
602 but it had to be done as a second step, after the catchpoint had been
603 created, using the "condition" command.
605 * The "info static-tracepoint-marker" command will now also work on
606 native Linux targets with in-process agent.
608 * GDB can now set breakpoints on inlined functions.
610 * The .gdb_index section has been updated to include symbols for
611 inlined functions. GDB will ignore older .gdb_index sections by
612 default, which could cause symbol files to be loaded more slowly
613 until their .gdb_index sections can be recreated. The new command
614 "set use-deprecated-index-sections on" will cause GDB to use any older
615 .gdb_index sections it finds. This will restore performance, but the
616 ability to set breakpoints on inlined functions will be lost in symbol
617 files with older .gdb_index sections.
619 The .gdb_index section has also been updated to record more information
620 about each symbol. This speeds up the "info variables", "info functions"
621 and "info types" commands when used with programs having the .gdb_index
622 section, as well as speeding up debugging with shared libraries using
623 the .gdb_index section.
625 * Ada support for GDB/MI Variable Objects has been added.
627 * GDB can now support 'breakpoint always-inserted mode' in 'record'
632 ** New command -info-os is the MI equivalent of "info os".
634 ** Output logs ("set logging" and related) now include MI output.
638 ** "set use-deprecated-index-sections on|off"
639 "show use-deprecated-index-sections on|off"
640 Controls the use of deprecated .gdb_index sections.
642 ** "catch load" and "catch unload" can be used to stop when a shared
643 library is loaded or unloaded, respectively.
645 ** "enable count" can be used to auto-disable a breakpoint after
648 ** "info vtbl" can be used to show the virtual method tables for
649 C++ and Java objects.
651 ** "explore" and its sub commands "explore value" and "explore type"
652 can be used to recursively explore values and types of
653 expressions. These commands are available only if GDB is
654 configured with '--with-python'.
656 ** "info auto-load" shows status of all kinds of auto-loaded files,
657 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
658 sequences of commands files, "info auto-load python-scripts"
659 shows status of auto-loading Python script files,
660 "info auto-load local-gdbinit" shows status of loading init file
661 (.gdbinit) from current directory and "info auto-load libthread-db" shows
662 status of inferior specific thread debugging shared library loading.
664 ** "info auto-load-scripts", "set auto-load-scripts on|off"
665 and "show auto-load-scripts" commands have been deprecated, use their
666 "info auto-load python-scripts", "set auto-load python-scripts on|off"
667 and "show auto-load python-scripts" counterparts instead.
669 ** "dprintf location,format,args..." creates a dynamic printf, which
670 is basically a breakpoint that does a printf and immediately
671 resumes your program's execution, so it is like a printf that you
672 can insert dynamically at runtime instead of at compiletime.
674 ** "set print symbol"
676 Controls whether GDB attempts to display the symbol, if any,
677 corresponding to addresses it prints. This defaults to "on", but
678 you can set it to "off" to restore GDB's previous behavior.
680 * Deprecated commands
682 ** For the Renesas Super-H architecture, the "regs" command has been
683 deprecated, and "info all-registers" should be used instead.
687 Renesas RL78 rl78-*-elf
688 HP OpenVMS ia64 ia64-hp-openvms*
690 * GDBserver supports evaluation of breakpoint conditions. When
691 support is advertised by GDBserver, GDB may be told to send the
692 breakpoint conditions in bytecode form to GDBserver. GDBserver
693 will only report the breakpoint trigger to GDB when its condition
699 show mips compression
700 Select the compressed ISA encoding used in functions that have no symbol
701 information available. The encoding can be set to either of:
704 and is updated automatically from ELF file flags if available.
706 set breakpoint condition-evaluation
707 show breakpoint condition-evaluation
708 Control whether breakpoint conditions are evaluated by GDB ("host") or by
709 GDBserver ("target"). Default option "auto" chooses the most efficient
711 This option can improve debugger efficiency depending on the speed of the
715 Disable auto-loading globally.
718 Show auto-loading setting of all kinds of auto-loaded files.
720 set auto-load gdb-scripts on|off
721 show auto-load gdb-scripts
722 Control auto-loading of GDB canned sequences of commands files.
724 set auto-load python-scripts on|off
725 show auto-load python-scripts
726 Control auto-loading of Python script files.
728 set auto-load local-gdbinit on|off
729 show auto-load local-gdbinit
730 Control loading of init file (.gdbinit) from current directory.
732 set auto-load libthread-db on|off
733 show auto-load libthread-db
734 Control auto-loading of inferior specific thread debugging shared library.
736 set auto-load scripts-directory <dir1>[:<dir2>...]
737 show auto-load scripts-directory
738 Set a list of directories from which to load auto-loaded scripts.
739 Automatically loaded Python scripts and GDB scripts are located in one
740 of the directories listed by this option.
741 The delimiter (':' above) may differ according to the host platform.
743 set auto-load safe-path <dir1>[:<dir2>...]
744 show auto-load safe-path
745 Set a list of directories from which it is safe to auto-load files.
746 The delimiter (':' above) may differ according to the host platform.
748 set debug auto-load on|off
750 Control display of debugging info for auto-loading the files above.
752 set dprintf-style gdb|call|agent
754 Control the way in which a dynamic printf is performed; "gdb"
755 requests a GDB printf command, while "call" causes dprintf to call a
756 function in the inferior. "agent" requests that the target agent
757 (such as GDBserver) do the printing.
759 set dprintf-function <expr>
760 show dprintf-function
761 set dprintf-channel <expr>
763 Set the function and optional first argument to the call when using
764 the "call" style of dynamic printf.
766 set disconnected-dprintf on|off
767 show disconnected-dprintf
768 Control whether agent-style dynamic printfs continue to be in effect
769 after GDB disconnects.
771 * New configure options
774 Configure default value for the 'set auto-load scripts-directory'
775 setting above. It defaults to '$debugdir:$datadir/auto-load',
776 $debugdir representing global debugging info directories (available
777 via 'show debug-file-directory') and $datadir representing GDB's data
778 directory (available via 'show data-directory').
780 --with-auto-load-safe-path
781 Configure default value for the 'set auto-load safe-path' setting
782 above. It defaults to the --with-auto-load-dir setting.
784 --without-auto-load-safe-path
785 Set 'set auto-load safe-path' to '/', effectively disabling this
790 z0/z1 conditional breakpoints extension
792 The z0/z1 breakpoint insertion packets have been extended to carry
793 a list of conditional expressions over to the remote stub depending on the
794 condition evaluation mode. The use of this extension can be controlled
795 via the "set remote conditional-breakpoints-packet" command.
799 Specify the signals which the remote stub may pass to the debugged
800 program without GDB involvement.
802 * New command line options
804 --init-command=FILE, -ix Like --command, -x but execute it
805 before loading inferior.
806 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
807 execute it before loading inferior.
809 *** Changes in GDB 7.4
811 * GDB now handles ambiguous linespecs more consistently; the existing
812 FILE:LINE support has been expanded to other types of linespecs. A
813 breakpoint will now be set on all matching locations in all
814 inferiors, and locations will be added or removed according to
817 * GDB now allows you to skip uninteresting functions and files when
818 stepping with the "skip function" and "skip file" commands.
820 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
821 and "show remote hardware-watchpoint-length-limit". These allows to
822 set or show the maximum length limit (in bytes) of a remote
823 target hardware watchpoint.
825 This allows e.g. to use "unlimited" hardware watchpoints with the
826 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
827 watchpoints are slower than real hardware watchpoints but are
828 significantly faster than gdb software watchpoints.
832 ** The register_pretty_printer function in module gdb.printing now takes
833 an optional `replace' argument. If True, the new printer replaces any
836 ** The "maint set python print-stack on|off" command has been
837 deprecated and will be deleted in GDB 7.5.
838 A new command: "set python print-stack none|full|message" has
839 replaced it. Additionally, the default for "print-stack" is
840 now "message", which just prints the error message without
843 ** A prompt substitution hook (prompt_hook) is now available to the
846 ** A new Python module, gdb.prompt has been added to the GDB Python
847 modules library. This module provides functionality for
848 escape sequences in prompts (used by set/show
849 extended-prompt). These escape sequences are replaced by their
852 ** Python commands and convenience-functions located in
853 'data-directory'/python/gdb/command and
854 'data-directory'/python/gdb/function are now automatically loaded
857 ** Blocks now provide four new attributes. global_block and
858 static_block will return the global and static blocks
859 respectively. is_static and is_global are boolean attributes
860 that indicate if the block is one of those two types.
862 ** Symbols now provide the "type" attribute, the type of the symbol.
864 ** The "gdb.breakpoint" function has been deprecated in favor of
867 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
868 of a function. This class is based on the "finish" command
869 available in the CLI.
871 ** Type objects for struct and union types now allow access to
872 the fields using standard Python dictionary (mapping) methods.
873 For example, "some_type['myfield']" now works, as does
876 ** A new event "gdb.new_objfile" has been added, triggered by loading a
879 ** A new function, "deep_items" has been added to the gdb.types
880 module in the GDB Python modules library. This function returns
881 an iterator over the fields of a struct or union type. Unlike
882 the standard Python "iteritems" method, it will recursively traverse
883 any anonymous fields.
887 ** "*stopped" events can report several new "reason"s, such as
890 ** Breakpoint changes are now notified using new async records, like
891 "=breakpoint-modified".
893 ** New command -ada-task-info.
895 * libthread-db-search-path now supports two special values: $sdir and $pdir.
896 $sdir specifies the default system locations of shared libraries.
897 $pdir specifies the directory where the libpthread used by the application
900 GDB no longer looks in $sdir and $pdir after it has searched the directories
901 mentioned in libthread-db-search-path. If you want to search those
902 directories, they must be specified in libthread-db-search-path.
903 The default value of libthread-db-search-path on GNU/Linux and Solaris
904 systems is now "$sdir:$pdir".
906 $pdir is not supported by gdbserver, it is currently ignored.
907 $sdir is supported by gdbserver.
909 * New configure option --with-iconv-bin.
910 When using the internationalization support like the one in the GNU C
911 library, GDB will invoke the "iconv" program to get a list of supported
912 character sets. If this program lives in a non-standard location, one can
913 use this option to specify where to find it.
915 * When natively debugging programs on PowerPC BookE processors running
916 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
917 watchpoints, which specify a mask in addition to an address to watch.
918 The mask specifies that some bits of an address (the bits which are
919 reset in the mask) should be ignored when matching the address accessed
920 by the inferior against the watchpoint address. See the "PowerPC Embedded"
921 section in the user manual for more details.
923 * The new option --once causes GDBserver to stop listening for connections once
924 the first connection is made. The listening port used by GDBserver will
925 become available after that.
927 * New commands "info macros" and "alias" have been added.
929 * New function parameters suffix @entry specifies value of function parameter
930 at the time the function got called. Entry values are available only since
936 "!" is now an alias of the "shell" command.
937 Note that no space is needed between "!" and SHELL COMMAND.
941 watch EXPRESSION mask MASK_VALUE
942 The watch command now supports the mask argument which allows creation
943 of masked watchpoints, if the current architecture supports this feature.
945 info auto-load-scripts [REGEXP]
946 This command was formerly named "maintenance print section-scripts".
947 It is now generally useful and is no longer a maintenance-only command.
949 info macro [-all] [--] MACRO
950 The info macro command has new options `-all' and `--'. The first for
951 printing all definitions of a macro. The second for explicitly specifying
952 the end of arguments and the beginning of the macro name in case the macro
953 name starts with a hyphen.
955 collect[/s] EXPRESSIONS
956 The tracepoint collect command now takes an optional modifier "/s"
957 that directs it to dereference pointer-to-character types and
958 collect the bytes of memory up to a zero byte. The behavior is
959 similar to what you see when you use the regular print command on a
960 string. An optional integer following the "/s" sets a bound on the
961 number of bytes that will be collected.
964 The trace start command now interprets any supplied arguments as a
965 note to be recorded with the trace run, with an effect similar to
966 setting the variable trace-notes.
969 The trace stop command now interprets any arguments as a note to be
970 mentioned along with the tstatus report that the trace was stopped
971 with a command. The effect is similar to setting the variable
974 * Tracepoints can now be enabled and disabled at any time after a trace
975 experiment has been started using the standard "enable" and "disable"
976 commands. It is now possible to start a trace experiment with no enabled
977 tracepoints; GDB will display a warning, but will allow the experiment to
978 begin, assuming that tracepoints will be enabled as needed while the trace
981 * Fast tracepoints on 32-bit x86-architectures can now be placed at
982 locations with 4-byte instructions, when they were previously
983 limited to locations with instructions of 5 bytes or longer.
987 set debug dwarf2-read
988 show debug dwarf2-read
989 Turns on or off display of debugging messages related to reading
990 DWARF debug info. The default is off.
992 set debug symtab-create
993 show debug symtab-create
994 Turns on or off display of debugging messages related to symbol table
995 creation. The default is off.
999 Set the GDB prompt, and allow escape sequences to be inserted to
1000 display miscellaneous information (see 'help set extended-prompt'
1001 for the list of sequences). This prompt (and any information
1002 accessed through the escape sequences) is updated every time the
1003 prompt is displayed.
1005 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1006 show print entry-values
1007 Set printing of frame argument values at function entry. In some cases
1008 GDB can determine the value of function argument which was passed by the
1009 function caller, even if the value was modified inside the called function.
1011 set debug entry-values
1012 show debug entry-values
1013 Control display of debugging info for determining frame argument values at
1014 function entry and virtual tail call frames.
1016 set basenames-may-differ
1017 show basenames-may-differ
1018 Set whether a source file may have multiple base names.
1019 (A "base name" is the name of a file with the directory part removed.
1020 Example: The base name of "/home/user/hello.c" is "hello.c".)
1021 If set, GDB will canonicalize file names (e.g., expand symlinks)
1022 before comparing them. Canonicalization is an expensive operation,
1023 but it allows the same file be known by more than one base name.
1024 If not set (the default), all source files are assumed to have just
1025 one base name, and gdb will do file name comparisons more efficiently.
1031 Set a user name and notes for the current and any future trace runs.
1032 This is useful for long-running and/or disconnected traces, to
1033 inform others (or yourself) as to who is running the trace, supply
1034 contact information, or otherwise explain what is going on.
1036 set trace-stop-notes
1037 show trace-stop-notes
1038 Set a note attached to the trace run, that is displayed when the
1039 trace has been stopped by a tstop command. This is useful for
1040 instance as an explanation, if you are stopping a trace run that was
1041 started by someone else.
1043 * New remote packets
1047 Dynamically enable a tracepoint in a started trace experiment.
1051 Dynamically disable a tracepoint in a started trace experiment.
1055 Set the user and notes of the trace run.
1059 Query the current status of a tracepoint.
1063 Query the minimum length of instruction at which a fast tracepoint may
1066 * Dcache size (number of lines) and line-size are now runtime-configurable
1067 via "set dcache line" and "set dcache line-size" commands.
1071 Texas Instruments TMS320C6x tic6x-*-*
1075 Renesas RL78 rl78-*-elf
1077 *** Changes in GDB 7.3.1
1079 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1081 *** Changes in GDB 7.3
1083 * GDB has a new command: "thread find [REGEXP]".
1084 It finds the thread id whose name, target id, or thread extra info
1085 matches the given regular expression.
1087 * The "catch syscall" command now works on mips*-linux* targets.
1089 * The -data-disassemble MI command now supports modes 2 and 3 for
1090 dumping the instruction opcodes.
1092 * New command line options
1094 -data-directory DIR Specify DIR as the "data-directory".
1095 This is mostly for testing purposes.
1097 * The "maint set python auto-load on|off" command has been renamed to
1098 "set auto-load-scripts on|off".
1100 * GDB has a new command: "set directories".
1101 It is like the "dir" command except that it replaces the
1102 source path list instead of augmenting it.
1104 * GDB now understands thread names.
1106 On GNU/Linux, "info threads" will display the thread name as set by
1107 prctl or pthread_setname_np.
1109 There is also a new command, "thread name", which can be used to
1110 assign a name internally for GDB to display.
1113 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1114 has been integrated into GDB.
1118 ** The function gdb.Write now accepts an optional keyword 'stream'.
1119 This keyword, when provided, will direct the output to either
1120 stdout, stderr, or GDB's logging output.
1122 ** Parameters can now be be sub-classed in Python, and in particular
1123 you may implement the get_set_doc and get_show_doc functions.
1124 This improves how Parameter set/show documentation is processed
1125 and allows for more dynamic content.
1127 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1128 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1129 have an is_valid method.
1131 ** Breakpoints can now be sub-classed in Python, and in particular
1132 you may implement a 'stop' function that is executed each time
1133 the inferior reaches that breakpoint.
1135 ** New function gdb.lookup_global_symbol looks up a global symbol.
1137 ** GDB values in Python are now callable if the value represents a
1138 function. For example, if 'some_value' represents a function that
1139 takes two integer parameters and returns a value, you can call
1140 that function like so:
1142 result = some_value (10,20)
1144 ** Module gdb.types has been added.
1145 It contains a collection of utilities for working with gdb.Types objects:
1146 get_basic_type, has_field, make_enum_dict.
1148 ** Module gdb.printing has been added.
1149 It contains utilities for writing and registering pretty-printers.
1150 New classes: PrettyPrinter, SubPrettyPrinter,
1151 RegexpCollectionPrettyPrinter.
1152 New function: register_pretty_printer.
1154 ** New commands "info pretty-printers", "enable pretty-printer" and
1155 "disable pretty-printer" have been added.
1157 ** gdb.parameter("directories") is now available.
1159 ** New function gdb.newest_frame returns the newest frame in the
1162 ** The gdb.InferiorThread class has a new "name" attribute. This
1163 holds the thread's name.
1165 ** Python Support for Inferior events.
1166 Python scripts can add observers to be notified of events
1167 occurring in the process being debugged.
1168 The following events are currently supported:
1169 - gdb.events.cont Continue event.
1170 - gdb.events.exited Inferior exited event.
1171 - gdb.events.stop Signal received, and Breakpoint hit events.
1175 ** GDB now puts template parameters in scope when debugging in an
1176 instantiation. For example, if you have:
1178 template<int X> int func (void) { return X; }
1180 then if you step into func<5>, "print X" will show "5". This
1181 feature requires proper debuginfo support from the compiler; it
1182 was added to GCC 4.5.
1184 ** The motion commands "next", "finish", "until", and "advance" now
1185 work better when exceptions are thrown. In particular, GDB will
1186 no longer lose control of the inferior; instead, the GDB will
1187 stop the inferior at the point at which the exception is caught.
1188 This functionality requires a change in the exception handling
1189 code that was introduced in GCC 4.5.
1191 * GDB now follows GCC's rules on accessing volatile objects when
1192 reading or writing target state during expression evaluation.
1193 One notable difference to prior behavior is that "print x = 0"
1194 no longer generates a read of x; the value of the assignment is
1195 now always taken directly from the value being assigned.
1197 * GDB now has some support for using labels in the program's source in
1198 linespecs. For instance, you can use "advance label" to continue
1199 execution to a label.
1201 * GDB now has support for reading and writing a new .gdb_index
1202 section. This section holds a fast index of DWARF debugging
1203 information and can be used to greatly speed up GDB startup and
1204 operation. See the documentation for `save gdb-index' for details.
1206 * The "watch" command now accepts an optional "-location" argument.
1207 When used, this causes GDB to watch the memory referred to by the
1208 expression. Such a watchpoint is never deleted due to it going out
1211 * GDB now supports thread debugging of core dumps on GNU/Linux.
1213 GDB now activates thread debugging using the libthread_db library
1214 when debugging GNU/Linux core dumps, similarly to when debugging
1215 live processes. As a result, when debugging a core dump file, GDB
1216 is now able to display pthread_t ids of threads. For example, "info
1217 threads" shows the same output as when debugging the process when it
1218 was live. In earlier releases, you'd see something like this:
1221 * 1 LWP 6780 main () at main.c:10
1223 While now you see this:
1226 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1228 It is also now possible to inspect TLS variables when debugging core
1231 When debugging a core dump generated on a machine other than the one
1232 used to run GDB, you may need to point GDB at the correct
1233 libthread_db library with the "set libthread-db-search-path"
1234 command. See the user manual for more details on this command.
1236 * When natively debugging programs on PowerPC BookE processors running
1237 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1238 which stop execution of the inferior whenever it executes an instruction
1239 at any address within the specified range. See the "PowerPC Embedded"
1240 section in the user manual for more details.
1242 * New features in the GDB remote stub, GDBserver
1244 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1245 and i686 LynxOS (version 5.x).
1247 ** GDBserver is now supported on Blackfin Linux.
1249 * New native configurations
1251 ia64 HP-UX ia64-*-hpux*
1255 Analog Devices, Inc. Blackfin Processor bfin-*
1257 * Ada task switching is now supported on sparc-elf targets when
1258 debugging a program using the Ravenscar Profile. For more information,
1259 see the "Tasking Support when using the Ravenscar Profile" section
1260 in the GDB user manual.
1262 * Guile support was removed.
1264 * New features in the GNU simulator
1266 ** The --map-info flag lists all known core mappings.
1268 ** CFI flashes may be simulated via the "cfi" device.
1270 *** Changes in GDB 7.2
1272 * Shared library support for remote targets by default
1274 When GDB is configured for a generic, non-OS specific target, like
1275 for example, --target=arm-eabi or one of the many *-*-elf targets,
1276 GDB now queries remote stubs for loaded shared libraries using the
1277 `qXfer:libraries:read' packet. Previously, shared library support
1278 was always disabled for such configurations.
1282 ** Argument Dependent Lookup (ADL)
1284 In C++ ADL lookup directs function search to the namespaces of its
1285 arguments even if the namespace has not been imported.
1295 Here the compiler will search for `foo' in the namespace of 'b'
1296 and find A::foo. GDB now supports this. This construct is commonly
1297 used in the Standard Template Library for operators.
1299 ** Improved User Defined Operator Support
1301 In addition to member operators, GDB now supports lookup of operators
1302 defined in a namespace and imported with a `using' directive, operators
1303 defined in the global scope, operators imported implicitly from an
1304 anonymous namespace, and the ADL operators mentioned in the previous
1306 GDB now also supports proper overload resolution for all the previously
1307 mentioned flavors of operators.
1309 ** static const class members
1311 Printing of static const class members that are initialized in the
1312 class definition has been fixed.
1314 * Windows Thread Information Block access.
1316 On Windows targets, GDB now supports displaying the Windows Thread
1317 Information Block (TIB) structure. This structure is visible either
1318 by using the new command `info w32 thread-information-block' or, by
1319 dereferencing the new convenience variable named `$_tlb', a
1320 thread-specific pointer to the TIB. This feature is also supported
1321 when remote debugging using GDBserver.
1323 * Static tracepoints
1325 Static tracepoints are calls in the user program into a tracing
1326 library. One such library is a port of the LTTng kernel tracer to
1327 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1328 When debugging with GDBserver, GDB now supports combining the GDB
1329 tracepoint machinery with such libraries. For example: the user can
1330 use GDB to probe a static tracepoint marker (a call from the user
1331 program into the tracing library) with the new "strace" command (see
1332 "New commands" below). This creates a "static tracepoint" in the
1333 breakpoint list, that can be manipulated with the same feature set
1334 as fast and regular tracepoints. E.g., collect registers, local and
1335 global variables, collect trace state variables, and define
1336 tracepoint conditions. In addition, the user can collect extra
1337 static tracepoint marker specific data, by collecting the new
1338 $_sdata internal variable. When analyzing the trace buffer, you can
1339 inspect $_sdata like any other variable available to GDB. For more
1340 information, see the "Tracepoints" chapter in GDB user manual. New
1341 remote packets have been defined to support static tracepoints, see
1342 the "New remote packets" section below.
1344 * Better reconstruction of tracepoints after disconnected tracing
1346 GDB will attempt to download the original source form of tracepoint
1347 definitions when starting a trace run, and then will upload these
1348 upon reconnection to the target, resulting in a more accurate
1349 reconstruction of the tracepoints that are in use on the target.
1353 You can now exercise direct control over the ways that GDB can
1354 affect your program. For instance, you can disallow the setting of
1355 breakpoints, so that the program can run continuously (assuming
1356 non-stop mode). In addition, the "observer" variable is available
1357 to switch all of the different controls; in observer mode, GDB
1358 cannot affect the target's behavior at all, which is useful for
1359 tasks like diagnosing live systems in the field.
1361 * The new convenience variable $_thread holds the number of the
1364 * New remote packets
1368 Return the address of the Windows Thread Information Block of a given thread.
1372 In response to several of the tracepoint packets, the target may now
1373 also respond with a number of intermediate `qRelocInsn' request
1374 packets before the final result packet, to have GDB handle
1375 relocating an instruction to execute at a different address. This
1376 is particularly useful for stubs that support fast tracepoints. GDB
1377 reports support for this feature in the qSupported packet.
1381 List static tracepoint markers in the target program.
1385 List static tracepoint markers at a given address in the target
1388 qXfer:statictrace:read
1390 Read the static trace data collected (by a `collect $_sdata'
1391 tracepoint action). The remote stub reports support for this packet
1392 to gdb's qSupported query.
1396 Send the current settings of GDB's permission flags.
1400 Send part of the source (textual) form of a tracepoint definition,
1401 which includes location, conditional, and action list.
1403 * The source command now accepts a -s option to force searching for the
1404 script in the source search path even if the script name specifies
1407 * New features in the GDB remote stub, GDBserver
1409 - GDBserver now support tracepoints (including fast tracepoints, and
1410 static tracepoints). The feature is currently supported by the
1411 i386-linux and amd64-linux builds. See the "Tracepoints support
1412 in gdbserver" section in the manual for more information.
1414 GDBserver JIT compiles the tracepoint's conditional agent
1415 expression bytecode into native code whenever possible for low
1416 overhead dynamic tracepoints conditionals. For such tracepoints,
1417 an expression that examines program state is evaluated when the
1418 tracepoint is reached, in order to determine whether to capture
1419 trace data. If the condition is simple and false, processing the
1420 tracepoint finishes very quickly and no data is gathered.
1422 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1423 for static tracepoints support.
1425 - GDBserver now supports x86_64 Windows 64-bit debugging.
1427 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1428 it understands register description.
1430 * The --batch flag now disables pagination and queries.
1432 * X86 general purpose registers
1434 GDB now supports reading/writing byte, word and double-word x86
1435 general purpose registers directly. This means you can use, say,
1436 $ah or $ax to refer, respectively, to the byte register AH and
1437 16-bit word register AX that are actually portions of the 32-bit
1438 register EAX or 64-bit register RAX.
1440 * The `commands' command now accepts a range of breakpoints to modify.
1441 A plain `commands' following a command that creates multiple
1442 breakpoints affects all the breakpoints set by that command. This
1443 applies to breakpoints set by `rbreak', and also applies when a
1444 single `break' command creates multiple breakpoints (e.g.,
1445 breakpoints on overloaded c++ functions).
1447 * The `rbreak' command now accepts a filename specification as part of
1448 its argument, limiting the functions selected by the regex to those
1449 in the specified file.
1451 * Support for remote debugging Windows and SymbianOS shared libraries
1452 from Unix hosts has been improved. Non Windows GDB builds now can
1453 understand target reported file names that follow MS-DOS based file
1454 system semantics, such as file names that include drive letters and
1455 use the backslash character as directory separator. This makes it
1456 possible to transparently use the "set sysroot" and "set
1457 solib-search-path" on Unix hosts to point as host copies of the
1458 target's shared libraries. See the new command "set
1459 target-file-system-kind" described below, and the "Commands to
1460 specify files" section in the user manual for more information.
1464 eval template, expressions...
1465 Convert the values of one or more expressions under the control
1466 of the string template to a command line, and call it.
1468 set target-file-system-kind unix|dos-based|auto
1469 show target-file-system-kind
1470 Set or show the assumed file system kind for target reported file
1473 save breakpoints <filename>
1474 Save all current breakpoint definitions to a file suitable for use
1475 in a later debugging session. To read the saved breakpoint
1476 definitions, use the `source' command.
1478 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1481 info static-tracepoint-markers
1482 Display information about static tracepoint markers in the target.
1484 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1485 Define a static tracepoint by probing a marker at the given
1486 function, line, address, or marker ID.
1490 Enable and disable observer mode.
1492 set may-write-registers on|off
1493 set may-write-memory on|off
1494 set may-insert-breakpoints on|off
1495 set may-insert-tracepoints on|off
1496 set may-insert-fast-tracepoints on|off
1497 set may-interrupt on|off
1498 Set individual permissions for GDB effects on the target. Note that
1499 some of these settings can have undesirable or surprising
1500 consequences, particularly when changed in the middle of a session.
1501 For instance, disabling the writing of memory can prevent
1502 breakpoints from being inserted, cause single-stepping to fail, or
1503 even crash your program, if you disable after breakpoints have been
1504 inserted. However, GDB should not crash.
1506 set record memory-query on|off
1507 show record memory-query
1508 Control whether to stop the inferior if memory changes caused
1509 by an instruction cannot be recorded.
1514 The disassemble command now supports "start,+length" form of two arguments.
1518 ** GDB now provides a new directory location, called the python directory,
1519 where Python scripts written for GDB can be installed. The location
1520 of that directory is <data-directory>/python, where <data-directory>
1521 is the GDB data directory. For more details, see section `Scripting
1522 GDB using Python' in the manual.
1524 ** The GDB Python API now has access to breakpoints, symbols, symbol
1525 tables, program spaces, inferiors, threads and frame's code blocks.
1526 Additionally, GDB Parameters can now be created from the API, and
1527 manipulated via set/show in the CLI.
1529 ** New functions gdb.target_charset, gdb.target_wide_charset,
1530 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1532 ** New exception gdb.GdbError.
1534 ** Pretty-printers are now also looked up in the current program space.
1536 ** Pretty-printers can now be individually enabled and disabled.
1538 ** GDB now looks for names of Python scripts to auto-load in a
1539 special section named `.debug_gdb_scripts', in addition to looking
1540 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1542 * Tracepoint actions were unified with breakpoint commands. In particular,
1543 there are no longer differences in "info break" output for breakpoints and
1544 tracepoints and the "commands" command can be used for both tracepoints and
1545 regular breakpoints.
1549 ARM Symbian arm*-*-symbianelf*
1551 * D language support.
1552 GDB now supports debugging programs written in the D programming
1555 * GDB now supports the extended ptrace interface for PowerPC which is
1556 available since Linux kernel version 2.6.34. This automatically enables
1557 any hardware breakpoints and additional hardware watchpoints available in
1558 the processor. The old ptrace interface exposes just one hardware
1559 watchpoint and no hardware breakpoints.
1561 * GDB is now able to use the Data Value Compare (DVC) register available on
1562 embedded PowerPC processors to implement in hardware simple watchpoint
1563 conditions of the form:
1565 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1567 This works in native GDB running on Linux kernels with the extended ptrace
1568 interface mentioned above.
1570 *** Changes in GDB 7.1
1574 ** Namespace Support
1576 GDB now supports importing of namespaces in C++. This enables the
1577 user to inspect variables from imported namespaces. Support for
1578 namepace aliasing has also been added. So, if a namespace is
1579 aliased in the current scope (e.g. namepace C=A; ) the user can
1580 print variables using the alias (e.g. (gdb) print C::x).
1584 All known bugs relating to the printing of virtual base class were
1585 fixed. It is now possible to call overloaded static methods using a
1590 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1591 and reinterpret_cast<> are now handled by the C++ expression parser.
1595 Xilinx MicroBlaze microblaze-*-*
1600 Xilinx MicroBlaze microblaze
1603 * Multi-program debugging.
1605 GDB now has support for multi-program (a.k.a. multi-executable or
1606 multi-exec) debugging. This allows for debugging multiple inferiors
1607 simultaneously each running a different program under the same GDB
1608 session. See "Debugging Multiple Inferiors and Programs" in the
1609 manual for more information. This implied some user visible changes
1610 in the multi-inferior support. For example, "info inferiors" now
1611 lists inferiors that are not running yet or that have exited
1612 already. See also "New commands" and "New options" below.
1614 * New tracing features
1616 GDB's tracepoint facility now includes several new features:
1618 ** Trace state variables
1620 GDB tracepoints now include support for trace state variables, which
1621 are variables managed by the target agent during a tracing
1622 experiment. They are useful for tracepoints that trigger each
1623 other, so for instance one tracepoint can count hits in a variable,
1624 and then a second tracepoint has a condition that is true when the
1625 count reaches a particular value. Trace state variables share the
1626 $-syntax of GDB convenience variables, and can appear in both
1627 tracepoint actions and condition expressions. Use the "tvariable"
1628 command to create, and "info tvariables" to view; see "Trace State
1629 Variables" in the manual for more detail.
1633 GDB now includes an option for defining fast tracepoints, which
1634 targets may implement more efficiently, such as by installing a jump
1635 into the target agent rather than a trap instruction. The resulting
1636 speedup can be by two orders of magnitude or more, although the
1637 tradeoff is that some program locations on some target architectures
1638 might not allow fast tracepoint installation, for instance if the
1639 instruction to be replaced is shorter than the jump. To request a
1640 fast tracepoint, use the "ftrace" command, with syntax identical to
1641 the regular trace command.
1643 ** Disconnected tracing
1645 It is now possible to detach GDB from the target while it is running
1646 a trace experiment, then reconnect later to see how the experiment
1647 is going. In addition, a new variable disconnected-tracing lets you
1648 tell the target agent whether to continue running a trace if the
1649 connection is lost unexpectedly.
1653 GDB now has the ability to save the trace buffer into a file, and
1654 then use that file as a target, similarly to you can do with
1655 corefiles. You can select trace frames, print data that was
1656 collected in them, and use tstatus to display the state of the
1657 tracing run at the moment that it was saved. To create a trace
1658 file, use "tsave <filename>", and to use it, do "target tfile
1661 ** Circular trace buffer
1663 You can ask the target agent to handle the trace buffer as a
1664 circular buffer, discarding the oldest trace frames to make room for
1665 newer ones, by setting circular-trace-buffer to on. This feature may
1666 not be available for all target agents.
1671 The disassemble command, when invoked with two arguments, now requires
1672 the arguments to be comma-separated.
1675 The info variables command now displays variable definitions. Files
1676 which only declare a variable are not shown.
1679 The source command is now capable of sourcing Python scripts.
1680 This feature is dependent on the debugger being build with Python
1683 Related to this enhancement is also the introduction of a new command
1684 "set script-extension" (see below).
1686 * New commands (for set/show, see "New options" below)
1688 record save [<FILENAME>]
1689 Save a file (in core file format) containing the process record
1690 execution log for replay debugging at a later time.
1692 record restore <FILENAME>
1693 Restore the process record execution log that was saved at an
1694 earlier time, for replay debugging.
1696 add-inferior [-copies <N>] [-exec <FILENAME>]
1699 clone-inferior [-copies <N>] [ID]
1700 Make a new inferior ready to execute the same program another
1701 inferior has loaded.
1706 maint info program-spaces
1707 List the program spaces loaded into GDB.
1709 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1710 show remote interrupt-sequence
1711 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1712 as the sequence to the remote target in order to interrupt the execution.
1713 Ctrl-C is a default. Some system prefers BREAK which is high level of
1714 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1715 Magic SysRq g. It is BREAK signal and character 'g'.
1717 set remote interrupt-on-connect [on | off]
1718 show remote interrupt-on-connect
1719 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1720 remote target when gdb connects to it. This is needed when you debug
1723 set remotebreak [on | off]
1725 Deprecated. Use "set/show remote interrupt-sequence" instead.
1727 tvariable $NAME [ = EXP ]
1728 Create or modify a trace state variable.
1731 List trace state variables and their values.
1733 delete tvariable $NAME ...
1734 Delete one or more trace state variables.
1737 Evaluate the given expressions without collecting anything into the
1738 trace buffer. (Valid in tracepoint actions only.)
1740 ftrace FN / FILE:LINE / *ADDR
1741 Define a fast tracepoint at the given function, line, or address.
1743 * New expression syntax
1745 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1746 GDB now parses 0b101010 identically with 42.
1750 set follow-exec-mode new|same
1751 show follow-exec-mode
1752 Control whether GDB reuses the same inferior across an exec call or
1753 creates a new one. This is useful to be able to restart the old
1754 executable after the inferior having done an exec call.
1756 set default-collect EXPR, ...
1757 show default-collect
1758 Define a list of expressions to be collected at each tracepoint.
1759 This is a useful way to ensure essential items are not overlooked,
1760 such as registers or a critical global variable.
1762 set disconnected-tracing
1763 show disconnected-tracing
1764 If set to 1, the target is instructed to continue tracing if it
1765 loses its connection to GDB. If 0, the target is to stop tracing
1768 set circular-trace-buffer
1769 show circular-trace-buffer
1770 If set to on, the target is instructed to use a circular trace buffer
1771 and discard the oldest trace frames instead of stopping the trace due
1772 to a full trace buffer. If set to off, the trace stops when the buffer
1773 fills up. Some targets may not support this.
1775 set script-extension off|soft|strict
1776 show script-extension
1777 If set to "off", the debugger does not perform any script language
1778 recognition, and all sourced files are assumed to be GDB scripts.
1779 If set to "soft" (the default), files are sourced according to
1780 filename extension, falling back to GDB scripts if the first
1782 If set to "strict", files are sourced according to filename extension.
1784 set ada trust-PAD-over-XVS on|off
1785 show ada trust-PAD-over-XVS
1786 If off, activate a workaround against a bug in the debugging information
1787 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1788 the GCC sources for more information about the GNAT encoding and
1789 PAD types in particular). It is always safe to set this option to
1790 off, but this introduces a slight performance penalty. The default
1793 * Python API Improvements
1795 ** GDB provides the new class gdb.LazyString. This is useful in
1796 some pretty-printing cases. The new method gdb.Value.lazy_string
1797 provides a simple way to create objects of this type.
1799 ** The fields returned by gdb.Type.fields now have an
1800 `is_base_class' attribute.
1802 ** The new method gdb.Type.range returns the range of an array type.
1804 ** The new method gdb.parse_and_eval can be used to parse and
1805 evaluate an expression.
1807 * New remote packets
1810 Define a trace state variable.
1813 Get the current value of a trace state variable.
1816 Set desired tracing behavior upon disconnection.
1819 Set the trace buffer to be linear or circular.
1822 Get data about the tracepoints currently in use.
1826 Process record now works correctly with hardware watchpoints.
1828 Multiple bug fixes have been made to the mips-irix port, making it
1829 much more reliable. In particular:
1830 - Debugging threaded applications is now possible again. Previously,
1831 GDB would hang while starting the program, or while waiting for
1832 the program to stop at a breakpoint.
1833 - Attaching to a running process no longer hangs.
1834 - An error occurring while loading a core file has been fixed.
1835 - Changing the value of the PC register now works again. This fixes
1836 problems observed when using the "jump" command, or when calling
1837 a function from GDB, or even when assigning a new value to $pc.
1838 - With the "finish" and "return" commands, the return value for functions
1839 returning a small array is now correctly printed.
1840 - It is now possible to break on shared library code which gets executed
1841 during a shared library init phase (code executed while executing
1842 their .init section). Previously, the breakpoint would have no effect.
1843 - GDB is now able to backtrace through the signal handler for
1844 non-threaded programs.
1846 PIE (Position Independent Executable) programs debugging is now supported.
1847 This includes debugging execution of PIC (Position Independent Code) shared
1848 libraries although for that, it should be possible to run such libraries as an
1851 *** Changes in GDB 7.0
1853 * GDB now has an interface for JIT compilation. Applications that
1854 dynamically generate code can create symbol files in memory and register
1855 them with GDB. For users, the feature should work transparently, and
1856 for JIT developers, the interface is documented in the GDB manual in the
1857 "JIT Compilation Interface" chapter.
1859 * Tracepoints may now be conditional. The syntax is as for
1860 breakpoints; either an "if" clause appended to the "trace" command,
1861 or the "condition" command is available. GDB sends the condition to
1862 the target for evaluation using the same bytecode format as is used
1863 for tracepoint actions.
1865 * The disassemble command now supports: an optional /r modifier, print the
1866 raw instructions in hex as well as in symbolic form, and an optional /m
1867 modifier to print mixed source+assembly.
1869 * Process record and replay
1871 In a architecture environment that supports ``process record and
1872 replay'', ``process record and replay'' target can record a log of
1873 the process execution, and replay it with both forward and reverse
1876 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1877 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1878 set execution-direction {forward|reverse}, for targets that support
1881 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1882 feature is available with a native GDB running on kernel version
1885 * GDB now has support for multi-byte and wide character sets on the
1886 target. Strings whose character type is wchar_t, char16_t, or
1887 char32_t are now correctly printed. GDB supports wide- and unicode-
1888 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1889 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1890 `printf'. This feature requires iconv to work properly; if your
1891 system does not have a working iconv, GDB can use GNU libiconv. See
1892 the installation instructions for more information.
1894 * GDB now supports automatic retrieval of shared library files from
1895 remote targets. To use this feature, specify a system root that begins
1896 with the `remote:' prefix, either via the `set sysroot' command or via
1897 the `--with-sysroot' configure-time option.
1899 * "info sharedlibrary" now takes an optional regex of libraries to show,
1900 and it now reports if a shared library has no debugging information.
1902 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1903 now complete on file names.
1905 * When completing in expressions, gdb will attempt to limit
1906 completions to allowable structure or union fields, where appropriate.
1907 For instance, consider:
1909 # struct example { int f1; double f2; };
1910 # struct example variable;
1913 If the user types TAB at the end of this command line, the available
1914 completions will be "f1" and "f2".
1916 * Inlined functions are now supported. They show up in backtraces, and
1917 the "step", "next", and "finish" commands handle them automatically.
1919 * GDB now supports the token-splicing (##) and stringification (#)
1920 operators when expanding macros. It also supports variable-arity
1923 * GDB now supports inspecting extra signal information, exported by
1924 the new $_siginfo convenience variable. The feature is currently
1925 implemented on linux ARM, i386 and amd64.
1927 * GDB can now display the VFP floating point registers and NEON vector
1928 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1929 can provide these registers (requires Linux 2.6.30 or later). Remote
1930 and simulator targets may also provide them.
1932 * New remote packets
1935 Search memory for a sequence of bytes.
1938 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1939 operation over reliable transport links. Use of this packet is
1940 controlled by the `set remote noack-packet' command.
1943 Kill the process with the specified process ID. Use this in preference
1944 to `k' when multiprocess protocol extensions are supported.
1947 Obtains additional operating system information
1951 Read or write additional signal information.
1953 * Removed remote protocol undocumented extension
1955 An undocumented extension to the remote protocol's `S' stop reply
1956 packet that permited the stub to pass a process id was removed.
1957 Remote servers should use the `T' stop reply packet instead.
1959 * GDB now supports multiple function calling conventions according to the
1960 DWARF-2 DW_AT_calling_convention function attribute.
1962 * The SH target utilizes the aforementioned change to distinguish between gcc
1963 and Renesas calling convention. It also adds the new CLI commands
1964 `set/show sh calling-convention'.
1966 * GDB can now read compressed debug sections, as produced by GNU gold
1967 with the --compress-debug-sections=zlib flag.
1969 * 64-bit core files are now supported on AIX.
1971 * Thread switching is now supported on Tru64.
1973 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1974 which will be allocated using malloc later in program execution.
1976 * The qXfer:libraries:read remote procotol packet now allows passing a
1977 list of section offsets.
1979 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1980 conditions handling signals delivered during attach or thread creation
1981 have also been fixed.
1983 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1984 From the user's standpoint, all unqualified instances of True and False
1985 are treated as the standard definitions, regardless of context.
1987 * GDB now parses C++ symbol and type names more flexibly. For
1990 template<typename T> class C { };
1993 GDB will now correctly handle all of:
1995 ptype C<char const *>
1996 ptype C<char const*>
1997 ptype C<const char *>
1998 ptype C<const char*>
2000 * New features in the GDB remote stub, gdbserver
2002 - The "--wrapper" command-line argument tells gdbserver to use a
2003 wrapper program to launch programs for debugging.
2005 - On PowerPC and S/390 targets, it is now possible to use a single
2006 gdbserver executable to debug both 32-bit and 64-bit programs.
2007 (This requires gdbserver itself to be built as a 64-bit executable.)
2009 - gdbserver uses the new noack protocol mode for TCP connections to
2010 reduce communications latency, if also supported and enabled in GDB.
2012 - Support for the sparc64-linux-gnu target is now included in
2015 - The amd64-linux build of gdbserver now supports debugging both
2016 32-bit and 64-bit programs.
2018 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2019 now support hardware watchpoints, and will use them automatically
2024 GDB now has support for scripting using Python. Whether this is
2025 available is determined at configure time.
2027 New GDB commands can now be written in Python.
2029 * Ada tasking support
2031 Ada tasks can now be inspected in GDB. The following commands have
2035 Print the list of Ada tasks.
2037 Print detailed information about task number N.
2039 Print the task number of the current task.
2041 Switch the context of debugging to task number N.
2043 * Support for user-defined prefixed commands. The "define" command can
2044 add new commands to existing prefixes, e.g. "target".
2046 * Multi-inferior, multi-process debugging.
2048 GDB now has generalized support for multi-inferior debugging. See
2049 "Debugging Multiple Inferiors" in the manual for more information.
2050 Although availability still depends on target support, the command
2051 set is more uniform now. The GNU/Linux specific multi-forks support
2052 has been migrated to this new framework. This implied some user
2053 visible changes; see "New commands" and also "Removed commands"
2056 * Target descriptions can now describe the target OS ABI. See the
2057 "Target Description Format" section in the user manual for more
2060 * Target descriptions can now describe "compatible" architectures
2061 to indicate that the target can execute applications for a different
2062 architecture in addition to those for the main target architecture.
2063 See the "Target Description Format" section in the user manual for
2066 * Multi-architecture debugging.
2068 GDB now includes general supports for debugging applications on
2069 hybrid systems that use more than one single processor architecture
2070 at the same time. Each such hybrid architecture still requires
2071 specific support to be added. The only hybrid architecture supported
2072 in this version of GDB is the Cell Broadband Engine.
2074 * GDB now supports integrated debugging of Cell/B.E. applications that
2075 use both the PPU and SPU architectures. To enable support for hybrid
2076 Cell/B.E. debugging, you need to configure GDB to support both the
2077 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2078 --enable-targets configure option.
2080 * Non-stop mode debugging.
2082 For some targets, GDB now supports an optional mode of operation in
2083 which you can examine stopped threads while other threads continue
2084 to execute freely. This is referred to as non-stop mode, with the
2085 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2086 section in the user manual for more information.
2088 To be able to support remote non-stop debugging, a remote stub needs
2089 to implement the non-stop mode remote protocol extensions, as
2090 described in the "Remote Non-Stop" section of the user manual. The
2091 GDB remote stub, gdbserver, has been adjusted to support these
2092 extensions on linux targets.
2094 * New commands (for set/show, see "New options" below)
2096 catch syscall [NAME(S) | NUMBER(S)]
2097 Catch system calls. Arguments, which should be names of system
2098 calls or their numbers, mean catch only those syscalls. Without
2099 arguments, every syscall will be caught. When the inferior issues
2100 any of the specified syscalls, GDB will stop and announce the system
2101 call, both when it is called and when its call returns. This
2102 feature is currently available with a native GDB running on the
2103 Linux Kernel, under the following architectures: x86, x86_64,
2104 PowerPC and PowerPC64.
2106 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2108 Search memory for a sequence of bytes.
2110 maint set python print-stack
2111 maint show python print-stack
2112 Show a stack trace when an error is encountered in a Python script.
2115 Invoke CODE by passing it to the Python interpreter.
2120 These allow macros to be defined, undefined, and listed
2124 Show operating system information about processes.
2127 List the inferiors currently under GDB's control.
2130 Switch focus to inferior number NUM.
2133 Detach from inferior number NUM.
2136 Kill inferior number NUM.
2140 set spu stop-on-load
2141 show spu stop-on-load
2142 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2144 set spu auto-flush-cache
2145 show spu auto-flush-cache
2146 Control whether to automatically flush the software-managed cache
2147 during Cell/B.E. debugging.
2149 set sh calling-convention
2150 show sh calling-convention
2151 Control the calling convention used when calling SH target functions.
2154 show debug timestamp
2155 Control display of timestamps with GDB debugging output.
2157 set disassemble-next-line
2158 show disassemble-next-line
2159 Control display of disassembled source lines or instructions when
2162 set remote noack-packet
2163 show remote noack-packet
2164 Set/show the use of remote protocol QStartNoAckMode packet. See above
2165 under "New remote packets."
2167 set remote query-attached-packet
2168 show remote query-attached-packet
2169 Control use of remote protocol `qAttached' (query-attached) packet.
2171 set remote read-siginfo-object
2172 show remote read-siginfo-object
2173 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2176 set remote write-siginfo-object
2177 show remote write-siginfo-object
2178 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2181 set remote reverse-continue
2182 show remote reverse-continue
2183 Control use of remote protocol 'bc' (reverse-continue) packet.
2185 set remote reverse-step
2186 show remote reverse-step
2187 Control use of remote protocol 'bs' (reverse-step) packet.
2189 set displaced-stepping
2190 show displaced-stepping
2191 Control displaced stepping mode. Displaced stepping is a way to
2192 single-step over breakpoints without removing them from the debuggee.
2193 Also known as "out-of-line single-stepping".
2196 show debug displaced
2197 Control display of debugging info for displaced stepping.
2199 maint set internal-error
2200 maint show internal-error
2201 Control what GDB does when an internal error is detected.
2203 maint set internal-warning
2204 maint show internal-warning
2205 Control what GDB does when an internal warning is detected.
2210 Use a wrapper program to launch programs for debugging.
2212 set multiple-symbols (all|ask|cancel)
2213 show multiple-symbols
2214 The value of this variable can be changed to adjust the debugger behavior
2215 when an expression or a breakpoint location contains an ambiguous symbol
2216 name (an overloaded function name, for instance).
2218 set breakpoint always-inserted
2219 show breakpoint always-inserted
2220 Keep breakpoints always inserted in the target, as opposed to inserting
2221 them when resuming the target, and removing them when the target stops.
2222 This option can improve debugger performance on slow remote targets.
2224 set arm fallback-mode (arm|thumb|auto)
2225 show arm fallback-mode
2226 set arm force-mode (arm|thumb|auto)
2228 These commands control how ARM GDB determines whether instructions
2229 are ARM or Thumb. The default for both settings is auto, which uses
2230 the current CPSR value for instructions without symbols; previous
2231 versions of GDB behaved as if "set arm fallback-mode arm".
2233 set disable-randomization
2234 show disable-randomization
2235 Standalone programs run with the virtual address space randomization enabled
2236 by default on some platforms. This option keeps the addresses stable across
2237 multiple debugging sessions.
2241 Control whether other threads are stopped or not when some thread hits
2246 Requests that asynchronous execution is enabled in the target, if available.
2247 In this case, it's possible to resume target in the background, and interact
2248 with GDB while the target is running. "show target-async" displays the
2249 current state of asynchronous execution of the target.
2251 set target-wide-charset
2252 show target-wide-charset
2253 The target-wide-charset is the name of the character set that GDB
2254 uses when printing characters whose type is wchar_t.
2256 set tcp auto-retry (on|off)
2258 set tcp connect-timeout
2259 show tcp connect-timeout
2260 These commands allow GDB to retry failed TCP connections to a remote stub
2261 with a specified timeout period; this is useful if the stub is launched
2262 in parallel with GDB but may not be ready to accept connections immediately.
2264 set libthread-db-search-path
2265 show libthread-db-search-path
2266 Control list of directories which GDB will search for appropriate
2269 set schedule-multiple (on|off)
2270 show schedule-multiple
2271 Allow GDB to resume all threads of all processes or only threads of
2272 the current process.
2276 Use more aggressive caching for accesses to the stack. This improves
2277 performance of remote debugging (particularly backtraces) without
2278 affecting correctness.
2280 set interactive-mode (on|off|auto)
2281 show interactive-mode
2282 Control whether GDB runs in interactive mode (on) or not (off).
2283 When in interactive mode, GDB waits for the user to answer all
2284 queries. Otherwise, GDB does not wait and assumes the default
2285 answer. When set to auto (the default), GDB determines which
2286 mode to use based on the stdin settings.
2291 For program forks, this is replaced by the new more generic `info
2292 inferiors' command. To list checkpoints, you can still use the
2293 `info checkpoints' command, which was an alias for the `info forks'
2297 Replaced by the new `inferior' command. To switch between
2298 checkpoints, you can still use the `restart' command, which was an
2299 alias for the `fork' command.
2302 This is removed, since some targets don't have a notion of
2303 processes. To switch between processes, you can still use the
2304 `inferior' command using GDB's own inferior number.
2307 For program forks, this is replaced by the new more generic `kill
2308 inferior' command. To delete a checkpoint, you can still use the
2309 `delete checkpoint' command, which was an alias for the `delete
2313 For program forks, this is replaced by the new more generic `detach
2314 inferior' command. To detach a checkpoint, you can still use the
2315 `detach checkpoint' command, which was an alias for the `detach
2318 * New native configurations
2320 x86/x86_64 Darwin i[34567]86-*-darwin*
2322 x86_64 MinGW x86_64-*-mingw*
2326 Lattice Mico32 lm32-*
2327 x86 DICOS i[34567]86-*-dicos*
2328 x86_64 DICOS x86_64-*-dicos*
2331 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2332 (mingw32ce) debugging.
2338 These commands were actually not implemented on any target.
2340 *** Changes in GDB 6.8
2342 * New native configurations
2344 NetBSD/hppa hppa*-*netbsd*
2345 Xtensa GNU/Linux xtensa*-*-linux*
2349 NetBSD/hppa hppa*-*-netbsd*
2350 Xtensa GNU/Lunux xtensa*-*-linux*
2352 * Change in command line behavior -- corefiles vs. process ids.
2354 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2355 attaching to process NUMBER fails, GDB no longer attempts to open a
2356 core file named NUMBER. Attaching to a program using the -c option
2357 is no longer supported. Instead, use the '-p' or '--pid' options.
2359 * GDB can now be built as a native debugger for debugging Windows x86
2360 (mingw32) Portable Executable (PE) programs.
2362 * Pending breakpoints no longer change their number when their address
2365 * GDB now supports breakpoints with multiple locations,
2366 including breakpoints on C++ constructors, inside C++ templates,
2367 and in inlined functions.
2369 * GDB's ability to debug optimized code has been improved. GDB more
2370 accurately identifies function bodies and lexical blocks that occupy
2371 more than one contiguous range of addresses.
2373 * Target descriptions can now describe registers for PowerPC.
2375 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2376 registers on PowerPC targets.
2378 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2379 targets even when the libthread_db library is not available.
2381 * The GDB remote stub, gdbserver, now supports the new file transfer
2382 commands (remote put, remote get, and remote delete).
2384 * The GDB remote stub, gdbserver, now supports run and attach in
2385 extended-remote mode.
2387 * hppa*64*-*-hpux11* target broken
2388 The debugger is unable to start a program and fails with the following
2389 error: "Error trying to get information about dynamic linker".
2390 The gdb-6.7 release is also affected.
2392 * GDB now supports the --enable-targets= configure option to allow
2393 building a single GDB executable that supports multiple remote
2394 target architectures.
2396 * GDB now supports debugging C and C++ programs which use the
2397 Decimal Floating Point extension. In addition, the PowerPC target
2398 now has a set of pseudo-registers to inspect decimal float values
2399 stored in two consecutive float registers.
2401 * The -break-insert MI command can optionally create pending
2404 * Improved support for debugging Ada
2405 Many improvements to the Ada language support have been made. These
2407 - Better support for Ada2005 interface types
2408 - Improved handling of arrays and slices in general
2409 - Better support for Taft-amendment types
2410 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2412 - Improved command completion in Ada
2415 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2420 set print frame-arguments (all|scalars|none)
2421 show print frame-arguments
2422 The value of this variable can be changed to control which argument
2423 values should be printed by the debugger when displaying a frame.
2428 Transfer files to and from a remote target, and delete remote files.
2435 Transfer files to and from a remote target, and delete remote files.
2437 * New remote packets
2444 Open, close, read, write, and delete files on the remote system.
2447 Attach to an existing process on the remote system, in extended-remote
2451 Run a new process on the remote system, in extended-remote mode.
2453 *** Changes in GDB 6.7
2455 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2456 bfd, libiberty and opcodes, as revealed by static analysis donated by
2457 Coverity, Inc. (http://scan.coverity.com).
2459 * When looking up multiply-defined global symbols, GDB will now prefer the
2460 symbol definition in the current shared library if it was built using the
2461 -Bsymbolic linker option.
2463 * When the Text User Interface (TUI) is not configured, GDB will now
2464 recognize the -tui command-line option and print a message that the TUI
2467 * The GDB remote stub, gdbserver, now has lower overhead for high
2468 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2470 * GDB for MIPS targets now autodetects whether a remote target provides
2471 32-bit or 64-bit register values.
2473 * Support for C++ member pointers has been improved.
2475 * GDB now understands XML target descriptions, which specify the
2476 target's overall architecture. GDB can read a description from
2477 a local file or over the remote serial protocol.
2479 * Vectors of single-byte data use a new integer type which is not
2480 automatically displayed as character or string data.
2482 * The /s format now works with the print command. It displays
2483 arrays of single-byte integers and pointers to single-byte integers
2486 * Target descriptions can now describe target-specific registers,
2487 for architectures which have implemented the support (currently
2488 only ARM, M68K, and MIPS).
2490 * GDB and the GDB remote stub, gdbserver, now support the XScale
2493 * The GDB remote stub, gdbserver, has been updated to support
2494 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2495 has been rewritten to use the standard GDB remote protocol.
2497 * GDB can now step into C++ functions which are called through thunks.
2499 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2501 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2502 layout. It also supports a TextSeg= and DataSeg= response when only
2503 segment base addresses (rather than offsets) are available.
2505 * The /i format now outputs any trailing branch delay slot instructions
2506 immediately following the last instruction within the count specified.
2508 * The GDB remote protocol "T" stop reply packet now supports a
2509 "library" response. Combined with the new "qXfer:libraries:read"
2510 packet, this response allows GDB to debug shared libraries on targets
2511 where the operating system manages the list of loaded libraries (e.g.
2512 Windows and SymbianOS).
2514 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2515 (DLLs) on Windows and Windows CE targets.
2517 * GDB now supports a faster verification that a .debug file matches its binary
2518 according to its build-id signature, if the signature is present.
2524 Enable or disable hardware flow control (RTS/CTS) on the serial port
2525 when debugging using remote targets.
2527 set mem inaccessible-by-default
2528 show mem inaccessible-by-default
2529 If the target supplies a memory map, for instance via the remote
2530 protocol's "qXfer:memory-map:read" packet, setting this variable
2531 prevents GDB from accessing memory outside the memory map. This
2532 is useful for targets with memory mapped registers or which react
2533 badly to accesses of unmapped address space.
2535 set breakpoint auto-hw
2536 show breakpoint auto-hw
2537 If the target supplies a memory map, for instance via the remote
2538 protocol's "qXfer:memory-map:read" packet, setting this variable
2539 lets GDB use hardware breakpoints automatically for memory regions
2540 where it can not use software breakpoints. This covers both the
2541 "break" command and internal breakpoints used for other commands
2542 including "next" and "finish".
2545 catch exception unhandled
2546 Stop the program execution when Ada exceptions are raised.
2549 Stop the program execution when an Ada assertion failed.
2553 Set an alternate system root for target files. This is a more
2554 general version of "set solib-absolute-prefix", which is now
2555 an alias to "set sysroot".
2558 Provide extended SPU facility status information. This set of
2559 commands is available only when debugging the Cell/B.E. SPU
2562 * New native configurations
2564 OpenBSD/sh sh*-*openbsd*
2567 unset tdesc filename
2569 Use the specified local file as an XML target description, and do
2570 not query the target for its built-in description.
2574 OpenBSD/sh sh*-*-openbsd*
2575 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2576 Toshiba Media Processor mep-elf
2578 * New remote packets
2581 Ignore the specified signals; pass them directly to the debugged program
2582 without stopping other threads or reporting them to GDB.
2584 qXfer:features:read:
2585 Read an XML target description from the target, which describes its
2590 Read or write contents of an spufs file on the target system. These
2591 packets are available only on the Cell/B.E. SPU architecture.
2593 qXfer:libraries:read:
2594 Report the loaded shared libraries. Combined with new "T" packet
2595 response, this packet allows GDB to debug shared libraries on
2596 targets where the operating system manages the list of loaded
2597 libraries (e.g. Windows and SymbianOS).
2601 Support for these obsolete configurations has been removed.
2609 i[34567]86-*-lynxos*
2610 i[34567]86-*-netware*
2611 i[34567]86-*-sco3.2v5*
2612 i[34567]86-*-sco3.2v4*
2614 i[34567]86-*-sysv4.2*
2617 i[34567]86-*-unixware2*
2618 i[34567]86-*-unixware*
2627 * Other removed features
2634 Various m68k-only ROM monitors.
2641 Various Renesas ROM monitors and debugging interfaces for SH and
2646 Support for a Macraigor serial interface to on-chip debugging.
2647 GDB does not directly support the newer parallel or USB
2652 A debug information format. The predecessor to DWARF 2 and
2653 DWARF 3, which are still supported.
2655 Support for the HP aCC compiler on HP-UX/PA-RISC
2657 SOM-encapsulated symbolic debugging information, automatic
2658 invocation of pxdb, and the aCC custom C++ ABI. This does not
2659 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2660 with aCC can still be debugged on an assembly level.
2662 MIPS ".pdr" sections
2664 A MIPS-specific format used to describe stack frame layout
2665 in debugging information.
2669 GDB could work with an older version of Guile to debug
2670 the interpreter and Scheme programs running in it.
2672 set mips stack-arg-size
2673 set mips saved-gpreg-size
2675 Use "set mips abi" to control parameter passing for MIPS.
2677 *** Changes in GDB 6.6
2682 Cell Broadband Engine SPU spu-elf
2684 * GDB can now be configured as a cross-debugger targeting native Windows
2685 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2686 running on a Windows system over TCP/IP to debug Windows programs.
2688 * The GDB remote stub, gdbserver, has been updated to support Windows and
2689 Cygwin debugging. Both single-threaded and multi-threaded programs are
2692 * The "set trust-readonly-sections" command works again. This command was
2693 broken in GDB 6.3, 6.4, and 6.5.
2695 * The "load" command now supports writing to flash memory, if the remote
2696 stub provides the required support.
2698 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2699 longer requires symbolic debug information (e.g. DWARF-2).
2704 unset substitute-path
2705 show substitute-path
2706 Manage a list of substitution rules that GDB uses to rewrite the name
2707 of the directories where the sources are located. This can be useful
2708 for instance when the sources were moved to a different location
2709 between compilation and debugging.
2713 Print each CLI command as it is executed. Each command is prefixed with
2714 a number of `+' symbols representing the nesting depth.
2715 The source command now has a `-v' option to enable the same feature.
2719 The ARM Demon monitor support (RDP protocol, "target rdp").
2721 Kernel Object Display, an embedded debugging feature which only worked with
2722 an obsolete version of Cisco IOS.
2724 The 'set download-write-size' and 'show download-write-size' commands.
2726 * New remote packets
2729 Tell a stub about GDB client features, and request remote target features.
2730 The first feature implemented is PacketSize, which allows the target to
2731 specify the size of packets it can handle - to minimize the number of
2732 packets required and improve performance when connected to a remote
2736 Fetch an OS auxilliary vector from the remote stub. This packet is a
2737 more efficient replacement for qPart:auxv:read.
2739 qXfer:memory-map:read:
2740 Fetch a memory map from the remote stub, including information about
2741 RAM, ROM, and flash memory devices.
2746 Erase and program a flash memory device.
2748 * Removed remote packets
2751 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2752 used it, and only gdbserver implemented it.
2754 *** Changes in GDB 6.5
2758 Renesas M32C/M16C m32c-elf
2760 Morpho Technologies ms1 ms1-elf
2764 init-if-undefined Initialize a convenience variable, but
2765 only if it doesn't already have a value.
2767 The following commands are presently only implemented for native GNU/Linux:
2769 checkpoint Save a snapshot of the program state.
2771 restart <n> Return the program state to a
2772 previously saved state.
2774 info checkpoints List currently saved checkpoints.
2776 delete-checkpoint <n> Delete a previously saved checkpoint.
2778 set|show detach-on-fork Tell gdb whether to detach from a newly
2779 forked process, or to keep debugging it.
2781 info forks List forks of the user program that
2782 are available to be debugged.
2784 fork <n> Switch to debugging one of several
2785 forks of the user program that are
2786 available to be debugged.
2788 delete-fork <n> Delete a fork from the list of forks
2789 that are available to be debugged (and
2790 kill the forked process).
2792 detach-fork <n> Delete a fork from the list of forks
2793 that are available to be debugged (and
2794 allow the process to continue).
2798 Morpho Technologies ms2 ms1-elf
2800 * Improved Windows host support
2802 GDB now builds as a cross debugger hosted on i686-mingw32, including
2803 native console support, and remote communications using either
2804 network sockets or serial ports.
2806 * Improved Modula-2 language support
2808 GDB can now print most types in the Modula-2 syntax. This includes:
2809 basic types, set types, record types, enumerated types, range types,
2810 pointer types and ARRAY types. Procedure var parameters are correctly
2811 printed and hexadecimal addresses and character constants are also
2812 written in the Modula-2 syntax. Best results can be obtained by using
2813 GNU Modula-2 together with the -gdwarf-2 command line option.
2817 The ARM rdi-share module.
2819 The Netware NLM debug server.
2821 *** Changes in GDB 6.4
2823 * New native configurations
2825 OpenBSD/arm arm*-*-openbsd*
2826 OpenBSD/mips64 mips64-*-openbsd*
2830 Morpho Technologies ms1 ms1-elf
2832 * New command line options
2834 --batch-silent As for --batch, but totally silent.
2835 --return-child-result The debugger will exist with the same value
2836 the child (debugged) program exited with.
2837 --eval-command COMMAND, -ex COMMAND
2838 Execute a single GDB CLI command. This may be
2839 specified multiple times and in conjunction
2840 with the --command (-x) option.
2842 * Deprecated commands removed
2844 The following commands, that were deprecated in 2000, have been
2848 set|show arm disassembly-flavor set|show arm disassembler
2849 othernames set arm disassembler
2850 set|show remotedebug set|show debug remote
2851 set|show archdebug set|show debug arch
2852 set|show eventdebug set|show debug event
2855 * New BSD user-level threads support
2857 It is now possible to debug programs using the user-level threads
2858 library on OpenBSD and FreeBSD. Currently supported (target)
2861 FreeBSD/amd64 x86_64-*-freebsd*
2862 FreeBSD/i386 i386-*-freebsd*
2863 OpenBSD/i386 i386-*-openbsd*
2865 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2866 are not yet supported.
2868 * New support for Matsushita MN10300 w/sim added
2869 (Work in progress). mn10300-elf.
2871 * REMOVED configurations and files
2873 VxWorks and the XDR protocol *-*-vxworks
2874 Motorola MCORE mcore-*-*
2875 National Semiconductor NS32000 ns32k-*-*
2877 * New "set print array-indexes" command
2879 After turning this setting "on", GDB prints the index of each element
2880 when displaying arrays. The default is "off" to preserve the previous
2883 * VAX floating point support
2885 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2887 * User-defined command support
2889 In addition to using $arg0..$arg9 for argument passing, it is now possible
2890 to use $argc to determine now many arguments have been passed. See the
2891 section on user-defined commands in the user manual for more information.
2893 *** Changes in GDB 6.3:
2895 * New command line option
2897 GDB now accepts -l followed by a number to set the timeout for remote
2900 * GDB works with GCC -feliminate-dwarf2-dups
2902 GDB now supports a more compact representation of DWARF-2 debug
2903 information using DW_FORM_ref_addr references. These are produced
2904 by GCC with the option -feliminate-dwarf2-dups and also by some
2905 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2906 to use -feliminate-dwarf2-dups.
2908 * Internationalization
2910 When supported by the host system, GDB will be built with
2911 internationalization (libintl). The task of marking up the sources is
2912 continued, we're looking forward to our first translation.
2916 Initial support for debugging programs compiled with the GNAT
2917 implementation of the Ada programming language has been integrated
2918 into GDB. In this release, support is limited to expression evaluation.
2920 * New native configurations
2922 GNU/Linux/m32r m32r-*-linux-gnu
2926 GDB's remote protocol now includes support for the 'p' packet. This
2927 packet is used to fetch individual registers from a remote inferior.
2929 * END-OF-LIFE registers[] compatibility module
2931 GDB's internal register infrastructure has been completely rewritten.
2932 The new infrastructure making possible the implementation of key new
2933 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2936 GDB 6.3 will be the last release to include the the registers[]
2937 compatibility module that allowed out-of-date configurations to
2938 continue to work. This change directly impacts the following
2948 powerpc bdm protocol
2950 Unless there is activity to revive these configurations, they will be
2951 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2953 * OBSOLETE configurations and files
2955 Configurations that have been declared obsolete in this release have
2956 been commented out. Unless there is activity to revive these
2957 configurations, the next release of GDB will have their sources
2958 permanently REMOVED.
2967 *** Changes in GDB 6.2.1:
2969 * MIPS `break main; run' gave an heuristic-fence-post warning
2971 When attempting to run even a simple program, a warning about
2972 heuristic-fence-post being hit would be reported. This problem has
2975 * MIPS IRIX 'long double' crashed GDB
2977 When examining a long double variable, GDB would get a segmentation
2978 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2979 IRIX long double values).
2983 A bug in the VAX stack code was causing problems with the "next"
2984 command. This problem has been fixed.
2986 *** Changes in GDB 6.2:
2988 * Fix for ``many threads''
2990 On GNU/Linux systems that use the NPTL threads library, a program
2991 rapidly creating and deleting threads would confuse GDB leading to the
2994 ptrace: No such process.
2995 thread_db_get_info: cannot get thread info: generic error
2997 This problem has been fixed.
2999 * "-async" and "-noasync" options removed.
3001 Support for the broken "-noasync" option has been removed (it caused
3004 * New ``start'' command.
3006 This command runs the program until the begining of the main procedure.
3008 * New BSD Kernel Data Access Library (libkvm) interface
3010 Using ``target kvm'' it is now possible to debug kernel core dumps and
3011 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3012 platforms. Currently supported (native-only) configurations are:
3014 FreeBSD/amd64 x86_64-*-freebsd*
3015 FreeBSD/i386 i?86-*-freebsd*
3016 NetBSD/i386 i?86-*-netbsd*
3017 NetBSD/m68k m68*-*-netbsd*
3018 NetBSD/sparc sparc-*-netbsd*
3019 OpenBSD/amd64 x86_64-*-openbsd*
3020 OpenBSD/i386 i?86-*-openbsd*
3021 OpenBSD/m68k m68*-openbsd*
3022 OpenBSD/sparc sparc-*-openbsd*
3024 * Signal trampoline code overhauled
3026 Many generic problems with GDB's signal handling code have been fixed.
3027 These include: backtraces through non-contiguous stacks; recognition
3028 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3029 call; backtrace through a signal trampoline; step into and out of
3030 signal handlers; and single-stepping in the signal trampoline.
3032 Please note that kernel bugs are a limiting factor here. These
3033 features have been shown to work on an s390 GNU/Linux system that
3034 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3036 * Cygwin support for DWARF 2 added.
3038 * New native configurations
3040 GNU/Linux/hppa hppa*-*-linux*
3041 OpenBSD/hppa hppa*-*-openbsd*
3042 OpenBSD/m68k m68*-*-openbsd*
3043 OpenBSD/m88k m88*-*-openbsd*
3044 OpenBSD/powerpc powerpc-*-openbsd*
3045 NetBSD/vax vax-*-netbsd*
3046 OpenBSD/vax vax-*-openbsd*
3048 * END-OF-LIFE frame compatibility module
3050 GDB's internal frame infrastructure has been completely rewritten.
3051 The new infrastructure making it possible to support key new features
3052 including DWARF 2 Call Frame Information. To aid in the task of
3053 migrating old configurations to this new infrastructure, a
3054 compatibility module, that allowed old configurations to continue to
3055 work, was also included.
3057 GDB 6.2 will be the last release to include this frame compatibility
3058 module. This change directly impacts the following configurations:
3068 Unless there is activity to revive these configurations, they will be
3069 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3071 * REMOVED configurations and files
3073 Sun 3, running SunOS 3 m68*-*-sunos3*
3074 Sun 3, running SunOS 4 m68*-*-sunos4*
3075 Sun 2, running SunOS 3 m68000-*-sunos3*
3076 Sun 2, running SunOS 4 m68000-*-sunos4*
3077 Motorola 680x0 running LynxOS m68*-*-lynxos*
3078 AT&T 3b1/Unix pc m68*-att-*
3079 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3080 decstation mips-dec-* mips-little-*
3081 riscos mips-*-riscos* mips-*-sysv*
3082 sonymips mips-sony-*
3083 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3085 *** Changes in GDB 6.1.1:
3087 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3089 The TUI (Text-mode User Interface) is now built as part of a default
3090 GDB configuration. It is enabled by either selecting the TUI with the
3091 command line option "-i=tui" or by running the separate "gdbtui"
3092 program. For more information on the TUI, see the manual "Debugging
3095 * Pending breakpoint support (also included in GDB 6.1)
3097 Support has been added to allow you to specify breakpoints in shared
3098 libraries that have not yet been loaded. If a breakpoint location
3099 cannot be found, and the "breakpoint pending" option is set to auto,
3100 GDB queries you if you wish to make the breakpoint pending on a future
3101 shared-library load. If and when GDB resolves the breakpoint symbol,
3102 the pending breakpoint is removed as one or more regular breakpoints
3105 Pending breakpoints are very useful for GCJ Java debugging.
3107 * Fixed ISO-C build problems
3109 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3110 non ISO-C code that stopped them being built using a more strict ISO-C
3111 compiler (e.g., IBM's C compiler).
3113 * Fixed build problem on IRIX 5
3115 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3116 wasn't able to compile compile on an IRIX 5 system.
3118 * Added execute permission to gdb/gdbserver/configure
3120 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3121 permission. This bug would cause configure to fail on a number of
3122 systems (Solaris, IRIX). Ref: server/519.
3124 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3126 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3127 has been updated to use constant array sizes.
3129 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3131 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3132 its generated DWARF Call Frame Info. This encoding was causing GDB to
3133 panic, that panic has been fixed. Ref: gdb/1628.
3135 * Fixed a problem when examining parameters in shared library code.
3137 When examining parameters in optimized shared library code generated
3138 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3139 not available''. GDB now correctly displays the variable's value.
3141 *** Changes in GDB 6.1:
3143 * Removed --with-mmalloc
3145 Support for the mmalloc memory manager has been removed, as it
3146 conflicted with the internal gdb byte cache.
3148 * Changes in AMD64 configurations
3150 The AMD64 target now includes the %cs and %ss registers. As a result
3151 the AMD64 remote protocol has changed; this affects the floating-point
3152 and SSE registers. If you rely on those registers for your debugging,
3153 you should upgrade gdbserver on the remote side.
3155 * Revised SPARC target
3157 The SPARC target has been completely revised, incorporating the
3158 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3159 support for LynxOS and SunOS 4 has been dropped. Calling functions
3160 from within GDB on operating systems with a non-executable stack
3161 (Solaris, OpenBSD) now works.
3165 GDB has a new C++ demangler which does a better job on the mangled
3166 names generated by current versions of g++. It also runs faster, so
3167 with this and other changes gdb should now start faster on large C++
3170 * DWARF 2 Location Expressions
3172 GDB support for location expressions has been extended to support function
3173 arguments and frame bases. Older versions of GDB could crash when they
3176 * C++ nested types and namespaces
3178 GDB's support for nested types and namespaces in C++ has been
3179 improved, especially if you use the DWARF 2 debugging format. (This
3180 is the default for recent versions of GCC on most platforms.)
3181 Specifically, if you have a class "Inner" defined within a class or
3182 namespace "Outer", then GDB realizes that the class's name is
3183 "Outer::Inner", not simply "Inner". This should greatly reduce the
3184 frequency of complaints about not finding RTTI symbols. In addition,
3185 if you are stopped at inside of a function defined within a namespace,
3186 GDB modifies its name lookup accordingly.
3188 * New native configurations
3190 NetBSD/amd64 x86_64-*-netbsd*
3191 OpenBSD/amd64 x86_64-*-openbsd*
3192 OpenBSD/alpha alpha*-*-openbsd*
3193 OpenBSD/sparc sparc-*-openbsd*
3194 OpenBSD/sparc64 sparc64-*-openbsd*
3196 * New debugging protocols
3198 M32R with SDI protocol m32r-*-elf*
3200 * "set prompt-escape-char" command deleted.
3202 The command "set prompt-escape-char" has been deleted. This command,
3203 and its very obscure effet on GDB's prompt, was never documented,
3204 tested, nor mentioned in the NEWS file.
3206 * OBSOLETE configurations and files
3208 Configurations that have been declared obsolete in this release have
3209 been commented out. Unless there is activity to revive these
3210 configurations, the next release of GDB will have their sources
3211 permanently REMOVED.
3213 Sun 3, running SunOS 3 m68*-*-sunos3*
3214 Sun 3, running SunOS 4 m68*-*-sunos4*
3215 Sun 2, running SunOS 3 m68000-*-sunos3*
3216 Sun 2, running SunOS 4 m68000-*-sunos4*
3217 Motorola 680x0 running LynxOS m68*-*-lynxos*
3218 AT&T 3b1/Unix pc m68*-att-*
3219 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3220 decstation mips-dec-* mips-little-*
3221 riscos mips-*-riscos* mips-*-sysv*
3222 sonymips mips-sony-*
3223 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3225 * REMOVED configurations and files
3227 SGI Irix-4.x mips-sgi-irix4 or iris4
3228 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3229 Z8000 simulator z8k-zilog-none or z8ksim
3230 Matsushita MN10200 w/simulator mn10200-*-*
3231 H8/500 simulator h8500-hitachi-hms or h8500hms
3232 HP/PA running BSD hppa*-*-bsd*
3233 HP/PA running OSF/1 hppa*-*-osf*
3234 HP/PA Pro target hppa*-*-pro*
3235 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3236 386BSD i[3456]86-*-bsd*
3237 Sequent family i[3456]86-sequent-sysv4*
3238 i[3456]86-sequent-sysv*
3239 i[3456]86-sequent-bsd*
3240 SPARC running LynxOS sparc-*-lynxos*
3241 SPARC running SunOS 4 sparc-*-sunos4*
3242 Tsqware Sparclet sparclet-*-*
3243 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3245 *** Changes in GDB 6.0:
3249 Support for debugging the Objective-C programming language has been
3250 integrated into GDB.
3252 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3254 DWARF 2's Call Frame Information makes available compiler generated
3255 information that more exactly describes the program's run-time stack.
3256 By using this information, GDB is able to provide more robust stack
3259 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3260 have been updated to use a new backtrace mechanism which includes
3261 DWARF 2 CFI support.
3265 GDB's remote protocol has been extended to include support for hosted
3266 file I/O (where the remote target uses GDB's file system). See GDB's
3267 remote protocol documentation for details.
3269 * All targets using the new architecture framework.
3271 All of GDB's targets have been updated to use the new internal
3272 architecture framework. The way is now open for future GDB releases
3273 to include cross-architecture native debugging support (i386 on amd64,
3276 * GNU/Linux's Thread Local Storage (TLS)
3278 GDB now includes support for for the GNU/Linux implementation of
3279 per-thread variables.
3281 * GNU/Linux's Native POSIX Thread Library (NPTL)
3283 GDB's thread code has been updated to work with either the new
3284 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3286 * Separate debug info.
3288 GDB, in conjunction with BINUTILS, now supports a mechanism for
3289 automatically loading debug information from a separate file. Instead
3290 of shipping full debug and non-debug versions of system libraries,
3291 system integrators can now instead ship just the stripped libraries
3292 and optional debug files.
3294 * DWARF 2 Location Expressions
3296 DWARF 2 Location Expressions allow the compiler to more completely
3297 describe the location of variables (even in optimized code) to the
3300 GDB now includes preliminary support for location expressions (support
3301 for DW_OP_piece is still missing).
3305 A number of long standing bugs that caused GDB to die while starting a
3306 Java application have been fixed. GDB's Java support is now
3307 considered "useable".
3309 * GNU/Linux support for fork, vfork, and exec.
3311 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3312 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3315 * GDB supports logging output to a file
3317 There are two new commands, "set logging" and "show logging", which can be
3318 used to capture GDB's output to a file.
3320 * The meaning of "detach" has changed for gdbserver
3322 The "detach" command will now resume the application, as documented. To
3323 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3326 * d10v, m68hc11 `regs' command deprecated
3328 The `info registers' command has been updated so that it displays the
3329 registers using a format identical to the old `regs' command.
3333 A new command, "maint set profile on/off", has been added. This command can
3334 be used to enable or disable profiling while running GDB, to profile a
3335 session or a set of commands. In addition there is a new configure switch,
3336 "--enable-profiling", which will cause GDB to be compiled with profiling
3337 data, for more informative profiling results.
3339 * Default MI syntax changed to "mi2".
3341 The default MI (machine interface) syntax, enabled by the command line
3342 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3343 "mi1", can be enabled by specifying the option "-i=mi1".
3345 Support for the original "mi0" syntax (included in GDB 5.0) has been
3348 Fix for gdb/192: removed extraneous space when displaying frame level.
3349 Fix for gdb/672: update changelist is now output in mi list format.
3350 Fix for gdb/702: a -var-assign that updates the value now shows up
3351 in a subsequent -var-update.
3353 * New native configurations.
3355 FreeBSD/amd64 x86_64-*-freebsd*
3357 * Multi-arched targets.
3359 HP/PA HPUX11 hppa*-*-hpux*
3360 Renesas M32R/D w/simulator m32r-*-elf*
3362 * OBSOLETE configurations and files
3364 Configurations that have been declared obsolete in this release have
3365 been commented out. Unless there is activity to revive these
3366 configurations, the next release of GDB will have their sources
3367 permanently REMOVED.
3369 Z8000 simulator z8k-zilog-none or z8ksim
3370 Matsushita MN10200 w/simulator mn10200-*-*
3371 H8/500 simulator h8500-hitachi-hms or h8500hms
3372 HP/PA running BSD hppa*-*-bsd*
3373 HP/PA running OSF/1 hppa*-*-osf*
3374 HP/PA Pro target hppa*-*-pro*
3375 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3376 Sequent family i[3456]86-sequent-sysv4*
3377 i[3456]86-sequent-sysv*
3378 i[3456]86-sequent-bsd*
3379 Tsqware Sparclet sparclet-*-*
3380 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3382 * REMOVED configurations and files
3385 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3386 IBM AIX PS/2 i[3456]86-*-aix
3387 i386 running Mach 3.0 i[3456]86-*-mach3*
3388 i386 running Mach i[3456]86-*-mach*
3389 i386 running OSF/1 i[3456]86-*osf1mk*
3390 HP/Apollo 68k Family m68*-apollo*-sysv*,
3392 m68*-hp-bsd*, m68*-hp-hpux*
3393 Argonaut Risc Chip (ARC) arc-*-*
3394 Mitsubishi D30V d30v-*-*
3395 Fujitsu FR30 fr30-*-elf*
3396 OS/9000 i[34]86-*-os9k
3397 I960 with MON960 i960-*-coff
3399 * MIPS $fp behavior changed
3401 The convenience variable $fp, for the MIPS, now consistently returns
3402 the address of the current frame's base. Previously, depending on the
3403 context, $fp could refer to either $sp or the current frame's base
3404 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3405 The GNU Source-Level Debugger''.
3407 *** Changes in GDB 5.3:
3409 * GNU/Linux shared library multi-threaded performance improved.
3411 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3412 `/proc', in preference to `ptrace' for memory reads. This may result
3413 in an improvement in the start-up time of multi-threaded, shared
3414 library applications when run under GDB. One GDB user writes: ``loads
3415 shared libs like mad''.
3417 * ``gdbserver'' now supports multi-threaded applications on some targets
3419 Support for debugging multi-threaded applications which use
3420 the GNU/Linux LinuxThreads package has been added for
3421 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3422 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3424 * GDB now supports C/C++ preprocessor macros.
3426 GDB now expands preprocessor macro invocations in C/C++ expressions,
3427 and provides various commands for showing macro definitions and how
3430 The new command `macro expand EXPRESSION' expands any macro
3431 invocations in expression, and shows the result.
3433 The new command `show macro MACRO-NAME' shows the definition of the
3434 macro named MACRO-NAME, and where it was defined.
3436 Most compilers don't include information about macros in the debugging
3437 information by default. In GCC 3.1, for example, you need to compile
3438 your program with the options `-gdwarf-2 -g3'. If the macro
3439 information is present in the executable, GDB will read it.
3441 * Multi-arched targets.
3443 DEC Alpha (partial) alpha*-*-*
3444 DEC VAX (partial) vax-*-*
3446 National Semiconductor NS32000 (partial) ns32k-*-*
3447 Motorola 68000 (partial) m68k-*-*
3448 Motorola MCORE mcore-*-*
3452 Fujitsu FRV architecture added by Red Hat frv*-*-*
3455 * New native configurations
3457 Alpha NetBSD alpha*-*-netbsd*
3458 SH NetBSD sh*-*-netbsdelf*
3459 MIPS NetBSD mips*-*-netbsd*
3460 UltraSPARC NetBSD sparc64-*-netbsd*
3462 * OBSOLETE configurations and files
3464 Configurations that have been declared obsolete in this release have
3465 been commented out. Unless there is activity to revive these
3466 configurations, the next release of GDB will have their sources
3467 permanently REMOVED.
3469 Mitsubishi D30V d30v-*-*
3470 OS/9000 i[34]86-*-os9k
3471 IBM AIX PS/2 i[3456]86-*-aix
3472 Fujitsu FR30 fr30-*-elf*
3473 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3474 Argonaut Risc Chip (ARC) arc-*-*
3475 i386 running Mach 3.0 i[3456]86-*-mach3*
3476 i386 running Mach i[3456]86-*-mach*
3477 i386 running OSF/1 i[3456]86-*osf1mk*
3478 HP/Apollo 68k Family m68*-apollo*-sysv*,
3480 m68*-hp-bsd*, m68*-hp-hpux*
3481 I960 with MON960 i960-*-coff
3483 * OBSOLETE languages
3485 CHILL, a Pascal like language used by telecommunications companies.
3487 * REMOVED configurations and files
3489 AMD 29k family via UDI a29k-amd-udi, udi29k
3490 A29K VxWorks a29k-*-vxworks
3491 AMD 29000 embedded, using EBMON a29k-none-none
3492 AMD 29000 embedded with COFF a29k-none-coff
3493 AMD 29000 embedded with a.out a29k-none-aout
3495 testsuite/gdb.hp/gdb.threads-hp/ directory
3497 * New command "set max-user-call-depth <nnn>"
3499 This command allows the user to limit the call depth of user-defined
3500 commands. The default is 1024.
3502 * Changes in FreeBSD/i386 native debugging.
3504 Support for the "generate-core-file" has been added.
3506 * New commands "dump", "append", and "restore".
3508 These commands allow data to be copied from target memory
3509 to a bfd-format or binary file (dump and append), and back
3510 from a file into memory (restore).
3512 * Improved "next/step" support on multi-processor Alpha Tru64.
3514 The previous single-step mechanism could cause unpredictable problems,
3515 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3516 of a software single-step mechanism prevents this.
3518 *** Changes in GDB 5.2.1:
3526 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3527 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3528 Fix, by Joel Brobecker imported from mainline.
3530 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3531 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3532 Fix, by Fred Fish, imported from mainline.
3534 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3535 Surprisingly enough, it works now.
3536 By Michal Ludvig, imported from mainline.
3538 i386 hardware watchpoint support:
3539 avoid misses on second run for some targets.
3540 By Pierre Muller, imported from mainline.
3542 *** Changes in GDB 5.2:
3544 * New command "set trust-readonly-sections on[off]".
3546 This command is a hint that tells gdb that read-only sections
3547 really are read-only (ie. that their contents will not change).
3548 In this mode, gdb will go to the object file rather than the
3549 target to read memory from read-only sections (such as ".text").
3550 This can be a significant performance improvement on some
3551 (notably embedded) targets.
3553 * New command "generate-core-file" (or "gcore").
3555 This new gdb command allows the user to drop a core file of the child
3556 process state at any time. So far it's been implemented only for
3557 GNU/Linux and Solaris, but should be relatively easily ported to other
3558 hosts. Argument is core file name (defaults to core.<pid>).
3560 * New command line option
3562 GDB now accepts --pid or -p followed by a process id.
3564 * Change in command line behavior -- corefiles vs. process ids.
3566 There is a subtle behavior in the way in which GDB handles
3567 command line arguments. The first non-flag argument is always
3568 a program to debug, but the second non-flag argument may either
3569 be a corefile or a process id. Previously, GDB would attempt to
3570 open the second argument as a corefile, and if that failed, would
3571 issue a superfluous error message and then attempt to attach it as
3572 a process. Now, if the second argument begins with a non-digit,
3573 it will be treated as a corefile. If it begins with a digit,
3574 GDB will attempt to attach it as a process, and if no such process
3575 is found, will then attempt to open it as a corefile.
3577 * Changes in ARM configurations.
3579 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3580 configuration is fully multi-arch.
3582 * New native configurations
3584 ARM NetBSD arm*-*-netbsd*
3585 x86 OpenBSD i[3456]86-*-openbsd*
3586 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3587 Sparc64 running FreeBSD sparc64-*-freebsd*
3591 Sanyo XStormy16 xstormy16-elf
3593 * OBSOLETE configurations and files
3595 Configurations that have been declared obsolete in this release have
3596 been commented out. Unless there is activity to revive these
3597 configurations, the next release of GDB will have their sources
3598 permanently REMOVED.
3600 AMD 29k family via UDI a29k-amd-udi, udi29k
3601 A29K VxWorks a29k-*-vxworks
3602 AMD 29000 embedded, using EBMON a29k-none-none
3603 AMD 29000 embedded with COFF a29k-none-coff
3604 AMD 29000 embedded with a.out a29k-none-aout
3606 testsuite/gdb.hp/gdb.threads-hp/ directory
3608 * REMOVED configurations and files
3610 TI TMS320C80 tic80-*-*
3612 PowerPC Solaris powerpcle-*-solaris*
3613 PowerPC Windows NT powerpcle-*-cygwin32
3614 PowerPC Netware powerpc-*-netware*
3615 Harris/CXUX m88k m88*-harris-cxux*
3616 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3617 ns32k-utek-sysv* ns32k-utek-*
3618 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3619 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3620 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3621 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3622 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3624 * Changes to command line processing
3626 The new `--args' feature can be used to specify command-line arguments
3627 for the inferior from gdb's command line.
3629 * Changes to key bindings
3631 There is a new `operate-and-get-next' function bound to `C-o'.
3633 *** Changes in GDB 5.1.1
3635 Fix compile problem on DJGPP.
3637 Fix a problem with floating-point registers on the i386 being
3640 Fix to stop GDB crashing on .debug_str debug info.
3642 Numerous documentation fixes.
3644 Numerous testsuite fixes.
3646 *** Changes in GDB 5.1:
3648 * New native configurations
3650 Alpha FreeBSD alpha*-*-freebsd*
3651 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3652 MIPS GNU/Linux mips*-*-linux*
3653 MIPS SGI Irix 6.x mips*-sgi-irix6*
3654 ia64 AIX ia64-*-aix*
3655 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3659 Motorola 68HC11 and 68HC12 m68hc11-elf
3661 UltraSparc running GNU/Linux sparc64-*-linux*
3663 * OBSOLETE configurations and files
3665 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3666 Harris/CXUX m88k m88*-harris-cxux*
3667 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3668 ns32k-utek-sysv* ns32k-utek-*
3669 TI TMS320C80 tic80-*-*
3671 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3672 PowerPC Solaris powerpcle-*-solaris*
3673 PowerPC Windows NT powerpcle-*-cygwin32
3674 PowerPC Netware powerpc-*-netware*
3675 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3676 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3677 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3678 Apple Macintosh (MPW) host N/A
3680 stuff.c (Program to stuff files into a specially prepared space in kdb)
3681 kdb-start.c (Main loop for the standalone kernel debugger)
3683 Configurations that have been declared obsolete in this release have
3684 been commented out. Unless there is activity to revive these
3685 configurations, the next release of GDB will have their sources
3686 permanently REMOVED.
3688 * REMOVED configurations and files
3690 Altos 3068 m68*-altos-*
3691 Convex c1-*-*, c2-*-*
3693 ARM RISCix arm-*-* (as host)
3697 * GDB has been converted to ISO C.
3699 GDB's source code has been converted to ISO C. In particular, the
3700 sources are fully protoized, and rely on standard headers being
3705 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3707 * The MI enabled by default.
3709 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3710 revised and enabled by default. Packages which use GDB as a debugging
3711 engine behind a UI or another front end are encouraged to switch to
3712 using the GDB/MI interface, instead of the old annotations interface
3713 which is now deprecated.
3715 * Support for debugging Pascal programs.
3717 GDB now includes support for debugging Pascal programs. The following
3718 main features are supported:
3720 - Pascal-specific data types such as sets;
3722 - automatic recognition of Pascal sources based on file-name
3725 - Pascal-style display of data types, variables, and functions;
3727 - a Pascal expression parser.
3729 However, some important features are not yet supported.
3731 - Pascal string operations are not supported at all;
3733 - there are some problems with boolean types;
3735 - Pascal type hexadecimal constants are not supported
3736 because they conflict with the internal variables format;
3738 - support for Pascal objects and classes is not full yet;
3740 - unlike Pascal, GDB is case-sensitive for symbol names.
3742 * Changes in completion.
3744 Commands such as `shell', `run' and `set args', which pass arguments
3745 to inferior programs, now complete on file names, similar to what
3746 users expect at the shell prompt.
3748 Commands which accept locations, such as `disassemble', `print',
3749 `breakpoint', `until', etc. now complete on filenames as well as
3750 program symbols. Thus, if you type "break foob TAB", and the source
3751 files linked into the programs include `foobar.c', that file name will
3752 be one of the candidates for completion. However, file names are not
3753 considered for completion after you typed a colon that delimits a file
3754 name from a name of a function in that file, as in "break foo.c:bar".
3756 `set demangle-style' completes on available demangling styles.
3758 * New platform-independent commands:
3760 It is now possible to define a post-hook for a command as well as a
3761 hook that runs before the command. For more details, see the
3762 documentation of `hookpost' in the GDB manual.
3764 * Changes in GNU/Linux native debugging.
3766 Support for debugging multi-threaded programs has been completely
3767 revised for all platforms except m68k and sparc. You can now debug as
3768 many threads as your system allows you to have.
3770 Attach/detach is supported for multi-threaded programs.
3772 Support for SSE registers was added for x86. This doesn't work for
3773 multi-threaded programs though.
3775 * Changes in MIPS configurations.
3777 Multi-arch support is enabled for all MIPS configurations.
3779 GDB can now be built as native debugger on SGI Irix 6.x systems for
3780 debugging n32 executables. (Debugging 64-bit executables is not yet
3783 * Unified support for hardware watchpoints in all x86 configurations.
3785 Most (if not all) native x86 configurations support hardware-assisted
3786 breakpoints and watchpoints in a unified manner. This support
3787 implements debug register sharing between watchpoints, which allows to
3788 put a virtually infinite number of watchpoints on the same address,
3789 and also supports watching regions up to 16 bytes with several debug
3792 The new maintenance command `maintenance show-debug-regs' toggles
3793 debugging print-outs in functions that insert, remove, and test
3794 watchpoints and hardware breakpoints.
3796 * Changes in the DJGPP native configuration.
3798 New command ``info dos sysinfo'' displays assorted information about
3799 the CPU, OS, memory, and DPMI server.
3801 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3802 display information about segment descriptors stored in GDT, LDT, and
3805 New commands ``info dos pde'' and ``info dos pte'' display entries
3806 from Page Directory and Page Tables (for now works with CWSDPMI only).
3807 New command ``info dos address-pte'' displays the Page Table entry for
3808 a given linear address.
3810 GDB can now pass command lines longer than 126 characters to the
3811 program being debugged (requires an update to the libdbg.a library
3812 which is part of the DJGPP development kit).
3814 DWARF2 debug info is now supported.
3816 It is now possible to `step' and `next' through calls to `longjmp'.
3818 * Changes in documentation.
3820 All GDB documentation was converted to GFDL, the GNU Free
3821 Documentation License.
3823 Tracepoints-related commands are now fully documented in the GDB
3826 TUI, the Text-mode User Interface, is now documented in the manual.
3828 Tracepoints-related commands are now fully documented in the GDB
3831 The "GDB Internals" manual now has an index. It also includes
3832 documentation of `ui_out' functions, GDB coding standards, x86
3833 hardware watchpoints, and memory region attributes.
3835 * GDB's version number moved to ``version.in''
3837 The Makefile variable VERSION has been replaced by the file
3838 ``version.in''. People creating GDB distributions should update the
3839 contents of this file.
3843 GUD support is now a standard part of the EMACS distribution.
3845 *** Changes in GDB 5.0:
3847 * Improved support for debugging FP programs on x86 targets
3849 Unified and much-improved support for debugging floating-point
3850 programs on all x86 targets. In particular, ``info float'' now
3851 displays the FP registers in the same format on all x86 targets, with
3852 greater level of detail.
3854 * Improvements and bugfixes in hardware-assisted watchpoints
3856 It is now possible to watch array elements, struct members, and
3857 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3858 on x86 targets no longer erroneously trigger when the address is
3861 * Improvements in the native DJGPP version of GDB
3863 The distribution now includes all the scripts and auxiliary files
3864 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3865 machines ``out of the box''.
3867 The DJGPP version can now debug programs that use signals. It is
3868 possible to catch signals that happened in the debuggee, deliver
3869 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3870 would kill the program being debugged.) Programs that hook hardware
3871 interrupts (keyboard, timer, etc.) can also be debugged.
3873 It is now possible to debug DJGPP programs that redirect their
3874 standard handles or switch them to raw (as opposed to cooked) mode, or
3875 even close them. The command ``run < foo > bar'' works as expected,
3876 and ``info terminal'' reports useful information about the debuggee's
3877 terminal, including raw/cooked mode, redirection, etc.
3879 The DJGPP version now uses termios functions for console I/O, which
3880 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3883 DOS-style file names with drive letters are now fully supported by
3886 It is now possible to debug DJGPP programs that switch their working
3887 directory. It is also possible to rerun the debuggee any number of
3888 times without restarting GDB; thus, you can use the same setup,
3889 breakpoints, etc. for many debugging sessions.
3891 * New native configurations
3893 ARM GNU/Linux arm*-*-linux*
3894 PowerPC GNU/Linux powerpc-*-linux*
3898 Motorola MCore mcore-*-*
3899 x86 VxWorks i[3456]86-*-vxworks*
3900 PowerPC VxWorks powerpc-*-vxworks*
3901 TI TMS320C80 tic80-*-*
3903 * OBSOLETE configurations
3905 Altos 3068 m68*-altos-*
3906 Convex c1-*-*, c2-*-*
3908 ARM RISCix arm-*-* (as host)
3911 Configurations that have been declared obsolete will be commented out,
3912 but the code will be left in place. If there is no activity to revive
3913 these configurations before the next release of GDB, the sources will
3914 be permanently REMOVED.
3916 * Gould support removed
3918 Support for the Gould PowerNode and NP1 has been removed.
3920 * New features for SVR4
3922 On SVR4 native platforms (such as Solaris), if you attach to a process
3923 without first loading a symbol file, GDB will now attempt to locate and
3924 load symbols from the running process's executable file.
3926 * Many C++ enhancements
3928 C++ support has been greatly improved. Overload resolution now works properly
3929 in almost all cases. RTTI support is on the way.
3931 * Remote targets can connect to a sub-program
3933 A popen(3) style serial-device has been added. This device starts a
3934 sub-process (such as a stand-alone simulator) and then communicates
3935 with that. The sub-program to run is specified using the syntax
3936 ``|<program> <args>'' vis:
3938 (gdb) set remotedebug 1
3939 (gdb) target extended-remote |mn10300-elf-sim program-args
3941 * MIPS 64 remote protocol
3943 A long standing bug in the mips64 remote protocol where by GDB
3944 expected certain 32 bit registers (ex SR) to be transfered as 32
3945 instead of 64 bits has been fixed.
3947 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3948 added to provide backward compatibility with older versions of GDB.
3950 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3952 The command ``set remotebinarydownload'' command has been replaced by
3953 ``set remote X-packet''. Other commands in ``set remote'' family
3954 include ``set remote P-packet''.
3956 * Breakpoint commands accept ranges.
3958 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3959 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3960 ``tracepoint passcount'' also accepts a range of tracepoints.
3962 * ``apropos'' command added.
3964 The ``apropos'' command searches through command names and
3965 documentation strings, printing out matches, making it much easier to
3966 try to find a command that does what you are looking for.
3970 A new machine oriented interface (MI) has been added to GDB. This
3971 interface is designed for debug environments running GDB as a separate
3972 process. This is part of the long term libGDB project. See the
3973 "GDB/MI" chapter of the GDB manual for further information. It can be
3974 enabled by configuring with:
3976 .../configure --enable-gdbmi
3978 *** Changes in GDB-4.18:
3980 * New native configurations
3982 HP-UX 10.20 hppa*-*-hpux10.20
3983 HP-UX 11.x hppa*-*-hpux11.0*
3984 M68K GNU/Linux m68*-*-linux*
3988 Fujitsu FR30 fr30-*-elf*
3989 Intel StrongARM strongarm-*-*
3990 Mitsubishi D30V d30v-*-*
3992 * OBSOLETE configurations
3994 Gould PowerNode, NP1 np1-*-*, pn-*-*
3996 Configurations that have been declared obsolete will be commented out,
3997 but the code will be left in place. If there is no activity to revive
3998 these configurations before the next release of GDB, the sources will
3999 be permanently REMOVED.
4003 As a compatibility experiment, GDB's source files buildsym.h and
4004 buildsym.c have been converted to pure standard C, no longer
4005 containing any K&R compatibility code. We believe that all systems in
4006 use today either come with a standard C compiler, or have a GCC port
4007 available. If this is not true, please report the affected
4008 configuration to bug-gdb@gnu.org immediately. See the README file for
4009 information about getting a standard C compiler if you don't have one
4014 GDB now uses readline 2.2.
4016 * set extension-language
4018 You can now control the mapping between filename extensions and source
4019 languages by using the `set extension-language' command. For instance,
4020 you can ask GDB to treat .c files as C++ by saying
4021 set extension-language .c c++
4022 The command `info extensions' lists all of the recognized extensions
4023 and their associated languages.
4025 * Setting processor type for PowerPC and RS/6000
4027 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4028 you can use the `set processor' command to specify what variant of the
4029 PowerPC family you are debugging. The command
4033 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4034 following PowerPC and RS6000 variants:
4036 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4037 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4039 403GC IBM PowerPC 403GC
4040 505 Motorola PowerPC 505
4041 860 Motorola PowerPC 860 or 850
4042 601 Motorola PowerPC 601
4043 602 Motorola PowerPC 602
4044 603 Motorola/IBM PowerPC 603 or 603e
4045 604 Motorola PowerPC 604 or 604e
4046 750 Motorola/IBM PowerPC 750 or 750
4048 At the moment, this command just tells GDB what to name the
4049 special-purpose processor registers. Since almost all the affected
4050 registers are inaccessible to user-level programs, this command is
4051 only useful for remote debugging in its present form.
4055 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4056 more extensive support for HP-UX. Added features include shared
4057 library support, kernel threads and hardware watchpoints for 11.00,
4058 support for HP's ANSI C and C++ compilers, and a compatibility mode
4059 for xdb and dbx commands.
4063 HP's donation includes the new concept of catchpoints, which is a
4064 generalization of the old catch command. On HP-UX, it is now possible
4065 to catch exec, fork, and vfork, as well as library loading.
4067 This means that the existing catch command has changed; its first
4068 argument now specifies the type of catch to be set up. See the
4069 output of "help catch" for a list of catchpoint types.
4071 * Debugging across forks
4073 On HP-UX, you can choose which process to debug when a fork() happens
4078 HP has donated a curses-based terminal user interface (TUI). To get
4079 it, build with --enable-tui. Although this can be enabled for any
4080 configuration, at present it only works for native HP debugging.
4082 * GDB remote protocol additions
4084 A new protocol packet 'X' that writes binary data is now available.
4085 Default behavior is to try 'X', then drop back to 'M' if the stub
4086 fails to respond. The settable variable `remotebinarydownload'
4087 allows explicit control over the use of 'X'.
4089 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4090 full 64-bit address. The command
4092 set remoteaddresssize 32
4094 can be used to revert to the old behaviour. For existing remote stubs
4095 the change should not be noticed, as the additional address information
4098 In order to assist in debugging stubs, you may use the maintenance
4099 command `packet' to send any text string to the stub. For instance,
4101 maint packet heythere
4103 sends the packet "$heythere#<checksum>". Note that it is very easy to
4104 disrupt a debugging session by sending the wrong packet at the wrong
4107 The compare-sections command allows you to compare section data on the
4108 target to what is in the executable file without uploading or
4109 downloading, by comparing CRC checksums.
4111 * Tracing can collect general expressions
4113 You may now collect general expressions at tracepoints. This requires
4114 further additions to the target-side stub; see tracepoint.c and
4115 doc/agentexpr.texi for further details.
4117 * mask-address variable for Mips
4119 For Mips targets, you may control the zeroing of the upper 32 bits of
4120 a 64-bit address by entering `set mask-address on'. This is mainly
4121 of interest to users of embedded R4xxx and R5xxx processors.
4123 * Higher serial baud rates
4125 GDB's serial code now allows you to specify baud rates 57600, 115200,
4126 230400, and 460800 baud. (Note that your host system may not be able
4127 to achieve all of these rates.)
4131 The i960 configuration now includes an initial implementation of a
4132 builtin simulator, contributed by Jim Wilson.
4135 *** Changes in GDB-4.17:
4137 * New native configurations
4139 Alpha GNU/Linux alpha*-*-linux*
4140 Unixware 2.x i[3456]86-unixware2*
4141 Irix 6.x mips*-sgi-irix6*
4142 PowerPC GNU/Linux powerpc-*-linux*
4143 PowerPC Solaris powerpcle-*-solaris*
4144 Sparc GNU/Linux sparc-*-linux*
4145 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4149 Argonaut Risc Chip (ARC) arc-*-*
4150 Hitachi H8/300S h8300*-*-*
4151 Matsushita MN10200 w/simulator mn10200-*-*
4152 Matsushita MN10300 w/simulator mn10300-*-*
4153 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4154 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4155 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4156 Mitsubishi D10V w/simulator d10v-*-*
4157 Mitsubishi M32R/D w/simulator m32r-*-elf*
4158 Tsqware Sparclet sparclet-*-*
4159 NEC V850 w/simulator v850-*-*
4161 * New debugging protocols
4163 ARM with RDI protocol arm*-*-*
4164 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4165 DDB and LSI variants of PMON protocol mips*-*-*
4166 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4167 PowerPC with SDS protocol powerpc{,le}-*-eabi
4168 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4172 All configurations can now understand and use the DWARF 2 debugging
4173 format. The choice is automatic, if the symbol file contains DWARF 2
4178 GDB now includes basic Java language support. This support is
4179 only useful with Java compilers that produce native machine code.
4181 * solib-absolute-prefix and solib-search-path
4183 For SunOS and SVR4 shared libraries, you may now set the prefix for
4184 loading absolute shared library symbol files, and the search path for
4185 locating non-absolute shared library symbol files.
4187 * Live range splitting
4189 GDB can now effectively debug code for which GCC has performed live
4190 range splitting as part of its optimization. See gdb/doc/LRS for
4191 more details on the expected format of the stabs information.
4195 GDB's support for the GNU Hurd, including thread debugging, has been
4196 updated to work with current versions of the Hurd.
4200 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4201 instruction set. ARM GDB automatically detects when Thumb
4202 instructions are in use, and adjusts disassembly and backtracing
4207 GDB's MIPS target configurations now handle the MIP16 16-bit
4212 GDB now includes support for overlays; if an executable has been
4213 linked such that multiple sections are based at the same address, GDB
4214 will decide which section to use for symbolic info. You can choose to
4215 control the decision manually, using overlay commands, or implement
4216 additional target-side support and use "overlay load-target" to bring
4217 in the overlay mapping. Do "help overlay" for more detail.
4221 The command "info symbol <address>" displays information about
4222 the symbol at the specified address.
4226 The standard remote protocol now includes an extension that allows
4227 asynchronous collection and display of trace data. This requires
4228 extensive support in the target-side debugging stub. Tracing mode
4229 includes a new interaction mode in GDB and new commands: see the
4230 file tracepoint.c for more details.
4234 Configurations for embedded MIPS now include a simulator contributed
4235 by Cygnus Solutions. The simulator supports the instruction sets
4236 of most MIPS variants.
4240 Sparc configurations may now include the ERC32 simulator contributed
4241 by the European Space Agency. The simulator is not built into
4242 Sparc targets by default; configure with --enable-sim to include it.
4246 For target configurations that may include multiple variants of a
4247 basic architecture (such as MIPS and SH), you may now set the
4248 architecture explicitly. "set arch" sets, "info arch" lists
4249 the possible architectures.
4251 *** Changes in GDB-4.16:
4253 * New native configurations
4255 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4256 M68K NetBSD m68k-*-netbsd*
4257 PowerPC AIX 4.x powerpc-*-aix*
4258 PowerPC MacOS powerpc-*-macos*
4259 PowerPC Windows NT powerpcle-*-cygwin32
4260 RS/6000 AIX 4.x rs6000-*-aix4*
4264 ARM with RDP protocol arm-*-*
4265 I960 with MON960 i960-*-coff
4266 MIPS VxWorks mips*-*-vxworks*
4267 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4268 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4270 Matra Sparclet sparclet-*-*
4274 The powerpc-eabi configuration now includes the PSIM simulator,
4275 contributed by Andrew Cagney, with assistance from Mike Meissner.
4276 PSIM is a very elaborate model of the PowerPC, including not only
4277 basic instruction set execution, but also details of execution unit
4278 performance and I/O hardware. See sim/ppc/README for more details.
4282 GDB now works with Solaris 2.5.
4284 * Windows 95/NT native
4286 GDB will now work as a native debugger on Windows 95 and Windows NT.
4287 To build it from source, you must use the "gnu-win32" environment,
4288 which uses a DLL to emulate enough of Unix to run the GNU tools.
4289 Further information, binaries, and sources are available at
4290 ftp.cygnus.com, under pub/gnu-win32.
4292 * dont-repeat command
4294 If a user-defined command includes the command `dont-repeat', then the
4295 command will not be repeated if the user just types return. This is
4296 useful if the command is time-consuming to run, so that accidental
4297 extra keystrokes don't run the same command many times.
4299 * Send break instead of ^C
4301 The standard remote protocol now includes an option to send a break
4302 rather than a ^C to the target in order to interrupt it. By default,
4303 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4305 * Remote protocol timeout
4307 The standard remote protocol includes a new variable `remotetimeout'
4308 that allows you to set the number of seconds before GDB gives up trying
4309 to read from the target. The default value is 2.
4311 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4313 By default GDB will automatically keep track of objects as they are
4314 loaded and unloaded by the dynamic linker. By using the command `set
4315 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4316 when shared library events occur, thus allowing you to set breakpoints
4317 in shared libraries which are explicitly loaded by the inferior.
4319 Note this feature does not work on hpux8. On hpux9 you must link
4320 /usr/lib/end.o into your program. This feature should work
4321 automatically on hpux10.
4323 * Irix 5.x hardware watchpoint support
4325 Irix 5 configurations now support the use of hardware watchpoints.
4327 * Mips protocol "SYN garbage limit"
4329 When debugging a Mips target using the `target mips' protocol, you
4330 may set the number of characters that GDB will ignore by setting
4331 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4332 every character. The default value is 1050.
4334 * Recording and replaying remote debug sessions
4336 If you set `remotelogfile' to the name of a file, gdb will write to it
4337 a recording of a remote debug session. This recording may then be
4338 replayed back to gdb using "gdbreplay". See gdbserver/README for
4339 details. This is useful when you have a problem with GDB while doing
4340 remote debugging; you can make a recording of the session and send it
4341 to someone else, who can then recreate the problem.
4343 * Speedups for remote debugging
4345 GDB includes speedups for downloading and stepping MIPS systems using
4346 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4347 and more efficient S-record downloading.
4349 * Memory use reductions and statistics collection
4351 GDB now uses less memory and reports statistics about memory usage.
4352 Try the `maint print statistics' command, for example.
4354 *** Changes in GDB-4.15:
4356 * Psymtabs for XCOFF
4358 The symbol reader for AIX GDB now uses partial symbol tables. This
4359 can greatly improve startup time, especially for large executables.
4361 * Remote targets use caching
4363 Remote targets now use a data cache to speed up communication with the
4364 remote side. The data cache could lead to incorrect results because
4365 it doesn't know about volatile variables, thus making it impossible to
4366 debug targets which use memory mapped I/O devices. `set remotecache
4367 off' turns the the data cache off.
4369 * Remote targets may have threads
4371 The standard remote protocol now includes support for multiple threads
4372 in the target system, using new protocol commands 'H' and 'T'. See
4373 gdb/remote.c for details.
4377 If GDB is configured with `--enable-netrom', then it will include
4378 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4379 acts as though it is a bank of ROM on the target board, but you can
4380 write into it over the network. GDB's support consists only of
4381 support for fast loading into the emulated ROM; to debug, you must use
4382 another protocol, such as standard remote protocol. The usual
4383 sequence is something like
4385 target nrom <netrom-hostname>
4387 target remote <netrom-hostname>:1235
4391 GDB now includes support for the Apple Macintosh, as a host only. It
4392 may be run as either an MPW tool or as a standalone application, and
4393 it can debug through the serial port. All the usual GDB commands are
4394 available, but to the target command, you must supply "serial" as the
4395 device type instead of "/dev/ttyXX". See mpw-README in the main
4396 directory for more information on how to build. The MPW configuration
4397 scripts */mpw-config.in support only a few targets, and only the
4398 mips-idt-ecoff target has been tested.
4402 GDB configuration now uses autoconf. This is not user-visible,
4403 but does simplify configuration and building.
4407 GDB now supports hpux10.
4409 *** Changes in GDB-4.14:
4411 * New native configurations
4413 x86 FreeBSD i[345]86-*-freebsd
4414 x86 NetBSD i[345]86-*-netbsd
4415 NS32k NetBSD ns32k-*-netbsd
4416 Sparc NetBSD sparc-*-netbsd
4420 A29K VxWorks a29k-*-vxworks
4421 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4422 CPU32 EST-300 emulator m68*-*-est*
4423 PowerPC ELF powerpc-*-elf
4426 * Alpha OSF/1 support for procfs
4428 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4429 possible to attach to running processes. As the mounting of the /proc
4430 filesystem is optional on the Alpha, GDB automatically determines
4431 the availability of /proc during startup. This can lead to problems
4432 if /proc is unmounted after GDB has been started.
4434 * Arguments to user-defined commands
4436 User commands may accept up to 10 arguments separated by whitespace.
4437 Arguments are accessed within the user command via $arg0..$arg9. A
4440 print $arg0 + $arg1 + $arg2
4442 To execute the command use:
4445 Defines the command "adder" which prints the sum of its three arguments.
4446 Note the arguments are text substitutions, so they may reference variables,
4447 use complex expressions, or even perform inferior function calls.
4449 * New `if' and `while' commands
4451 This makes it possible to write more sophisticated user-defined
4452 commands. Both commands take a single argument, which is the
4453 expression to evaluate, and must be followed by the commands to
4454 execute, one per line, if the expression is nonzero, the list being
4455 terminated by the word `end'. The `if' command list may include an
4456 `else' word, which causes the following commands to be executed only
4457 if the expression is zero.
4459 * Fortran source language mode
4461 GDB now includes partial support for Fortran 77. It will recognize
4462 Fortran programs and can evaluate a subset of Fortran expressions, but
4463 variables and functions may not be handled correctly. GDB will work
4464 with G77, but does not yet know much about symbols emitted by other
4467 * Better HPUX support
4469 Most debugging facilities now work on dynamic executables for HPPAs
4470 running hpux9 or later. You can attach to running dynamically linked
4471 processes, but by default the dynamic libraries will be read-only, so
4472 for instance you won't be able to put breakpoints in them. To change
4473 that behavior do the following before running the program:
4479 This will cause the libraries to be mapped private and read-write.
4480 To revert to the normal behavior, do this:
4486 You cannot set breakpoints or examine data in the library until after
4487 the library is loaded if the function/data symbols do not have
4490 GDB can now also read debug symbols produced by the HP C compiler on
4491 HPPAs (sorry, no C++, Fortran or 68k support).
4493 * Target byte order now dynamically selectable
4495 You can choose which byte order to use with a target system, via the
4496 commands "set endian big" and "set endian little", and you can see the
4497 current setting by using "show endian". You can also give the command
4498 "set endian auto", in which case GDB will use the byte order
4499 associated with the executable. Currently, only embedded MIPS
4500 configurations support dynamic selection of target byte order.
4502 * New DOS host serial code
4504 This version uses DPMI interrupts to handle buffered I/O, so you
4505 no longer need to run asynctsr when debugging boards connected to
4508 *** Changes in GDB-4.13:
4510 * New "complete" command
4512 This lists all the possible completions for the rest of the line, if it
4513 were to be given as a command itself. This is intended for use by emacs.
4515 * Trailing space optional in prompt
4517 "set prompt" no longer adds a space for you after the prompt you set. This
4518 allows you to set a prompt which ends in a space or one that does not.
4520 * Breakpoint hit counts
4522 "info break" now displays a count of the number of times the breakpoint
4523 has been hit. This is especially useful in conjunction with "ignore"; you
4524 can ignore a large number of breakpoint hits, look at the breakpoint info
4525 to see how many times the breakpoint was hit, then run again, ignoring one
4526 less than that number, and this will get you quickly to the last hit of
4529 * Ability to stop printing at NULL character
4531 "set print null-stop" will cause GDB to stop printing the characters of
4532 an array when the first NULL is encountered. This is useful when large
4533 arrays actually contain only short strings.
4535 * Shared library breakpoints
4537 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4538 breakpoints in shared libraries before the executable is run.
4540 * Hardware watchpoints
4542 There is a new hardware breakpoint for the watch command for sparclite
4543 targets. See gdb/sparclite/hw_breakpoint.note.
4545 Hardware watchpoints are also now supported under GNU/Linux.
4549 Annotations have been added. These are for use with graphical interfaces,
4550 and are still experimental. Currently only gdba.el uses these.
4552 * Improved Irix 5 support
4554 GDB now works properly with Irix 5.2.
4556 * Improved HPPA support
4558 GDB now works properly with the latest GCC and GAS.
4560 * New native configurations
4562 Sequent PTX4 i[34]86-sequent-ptx4
4563 HPPA running OSF/1 hppa*-*-osf*
4564 Atari TT running SVR4 m68*-*-sysv4*
4565 RS/6000 LynxOS rs6000-*-lynxos*
4569 OS/9000 i[34]86-*-os9k
4570 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4573 * Hitachi SH7000 and E7000-PC ICE support
4575 There is now support for communicating with the Hitachi E7000-PC ICE.
4576 This is available automatically when GDB is configured for the SH.
4580 As usual, a variety of small fixes and improvements, both generic
4581 and configuration-specific. See the ChangeLog for more detail.
4583 *** Changes in GDB-4.12:
4585 * Irix 5 is now supported
4589 GDB-4.12 on the HPPA has a number of changes which make it unable
4590 to debug the output from the currently released versions of GCC and
4591 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4592 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4593 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4596 *** Changes in GDB-4.11:
4598 * User visible changes:
4602 The "set remotedebug" option is now consistent between the mips remote
4603 target, remote targets using the gdb-specific protocol, UDI (AMD's
4604 debug protocol for the 29k) and the 88k bug monitor. It is now an
4605 integer specifying a debug level (normally 0 or 1, but 2 means more
4606 debugging info for the mips target).
4608 * DEC Alpha native support
4610 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4611 debug info, but GDB works fairly well with the DEC compiler and should
4612 work with a future GCC release. See the README file for a few
4613 Alpha-specific notes.
4615 * Preliminary thread implementation
4617 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4619 * LynxOS native and target support for 386
4621 This release has been hosted on LynxOS 2.2, and also can be configured
4622 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4625 * Improvements in C++ mangling/demangling.
4627 This release has much better g++ debugging, specifically in name
4628 mangling/demangling, virtual function calls, print virtual table,
4629 call methods, ...etc.
4631 *** Changes in GDB-4.10:
4633 * User visible changes:
4635 Remote debugging using the GDB-specific (`target remote') protocol now
4636 supports the `load' command. This is only useful if you have some
4637 other way of getting the stub to the target system, and you can put it
4638 somewhere in memory where it won't get clobbered by the download.
4640 Filename completion now works.
4642 When run under emacs mode, the "info line" command now causes the
4643 arrow to point to the line specified. Also, "info line" prints
4644 addresses in symbolic form (as well as hex).
4646 All vxworks based targets now support a user settable option, called
4647 vxworks-timeout. This option represents the number of seconds gdb
4648 should wait for responses to rpc's. You might want to use this if
4649 your vxworks target is, perhaps, a slow software simulator or happens
4650 to be on the far side of a thin network line.
4654 This release contains support for using a DEC alpha as a GDB host for
4655 cross debugging. Native alpha debugging is not supported yet.
4658 *** Changes in GDB-4.9:
4662 This is the first GDB release which is accompanied by a matching testsuite.
4663 The testsuite requires installation of dejagnu, which should be available
4664 via ftp from most sites that carry GNU software.
4668 'Cfront' style demangling has had its name changed to 'ARM' style, to
4669 emphasize that it was written from the specifications in the C++ Annotated
4670 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4671 disclaimers, it still generated too much confusion with users attempting to
4672 use gdb with AT&T cfront.
4676 GDB now uses a standard remote interface to a simulator library.
4677 So far, the library contains simulators for the Zilog Z8001/2, the
4678 Hitachi H8/300, H8/500 and Super-H.
4680 * New targets supported
4682 H8/300 simulator h8300-hitachi-hms or h8300hms
4683 H8/500 simulator h8500-hitachi-hms or h8500hms
4684 SH simulator sh-hitachi-hms or sh
4685 Z8000 simulator z8k-zilog-none or z8ksim
4686 IDT MIPS board over serial line mips-idt-ecoff
4688 Cross-debugging to GO32 targets is supported. It requires a custom
4689 version of the i386-stub.c module which is integrated with the
4690 GO32 memory extender.
4692 * New remote protocols
4694 MIPS remote debugging protocol.
4696 * New source languages supported
4698 This version includes preliminary support for Chill, a Pascal like language
4699 used by telecommunications companies. Chill support is also being integrated
4700 into the GNU compiler, but we don't know when it will be publically available.
4703 *** Changes in GDB-4.8:
4705 * HP Precision Architecture supported
4707 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4708 version of this support was available as a set of patches from the
4709 University of Utah. GDB does not support debugging of programs
4710 compiled with the HP compiler, because HP will not document their file
4711 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4712 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4714 Many problems in the preliminary version have been fixed.
4716 * Faster and better demangling
4718 We have improved template demangling and fixed numerous bugs in the GNU style
4719 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4720 character types (wchar_t) are now supported. Demangling of each symbol is now
4721 only done once, and is cached when the symbol table for a file is read in.
4722 This results in a small increase in memory usage for C programs, a moderate
4723 increase in memory usage for C++ programs, and a fantastic speedup in
4726 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4727 from the specifications in the Annotated Reference Manual, which AT&T's
4728 compiler does not actually implement.
4730 * G++ multiple inheritance compiler problem
4732 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4733 inheritance lattices was reworked to properly discover ambiguities. We
4734 recently found an example which causes this new algorithm to fail in a
4735 very subtle way, producing bad debug information for those classes.
4736 The file 'gcc.patch' (in this directory) can be applied to gcc to
4737 circumvent the problem. A future GCC release will contain a complete
4740 The previous G++ debug info problem (mentioned below for the gdb-4.7
4741 release) is fixed in gcc version 2.3.2.
4743 * Improved configure script
4745 The `configure' script will now attempt to guess your system type if
4746 you don't supply a host system type. The old scheme of supplying a
4747 host system triplet is preferable over using this. All the magic is
4748 done in the new `config.guess' script. Examine it for details.
4750 We have also brought our configure script much more in line with the FSF's
4751 version. It now supports the --with-xxx options. In particular,
4752 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4753 The resulting GDB will not be able to read arbitrary object file formats --
4754 only the format ``expected'' to be used on the configured target system.
4755 We hope to make this the default in a future release.
4757 * Documentation improvements
4759 There's new internal documentation on how to modify GDB, and how to
4760 produce clean changes to the code. We implore people to read it
4761 before submitting changes.
4763 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4764 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4765 `info' files are also provided. To build `info' files from scratch,
4766 you will need the latest `makeinfo' release, which will be available in
4767 a future texinfo-X.Y release.
4769 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4770 We're not sure exactly which versions have this problem, but it has
4771 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4772 or better. If that isn't possible, there is a patch in
4773 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4774 around this problem.
4778 GDB now supports array constants that can be used in expressions typed in by
4779 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4780 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4783 The new directory `gdb/sparclite' contains a program that demonstrates
4784 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4786 * New native hosts supported
4788 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4789 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4791 * New targets supported
4793 AMD 29k family via UDI a29k-amd-udi or udi29k
4795 * New file formats supported
4797 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4798 HPUX core files, and SCO 3.2v2 core files.
4802 Attaching to processes now works again; thanks for the many bug reports.
4804 We have also stomped on a bunch of core dumps caused by
4805 printf_filtered("%s") problems.
4807 We eliminated a copyright problem on the rpc and ptrace header files
4808 for VxWorks, which was discovered at the last minute during the 4.7
4809 release. You should now be able to build a VxWorks GDB.
4811 You can now interrupt gdb while an attached process is running. This
4812 will cause the attached process to stop, and give control back to GDB.
4814 We fixed problems caused by using too many file descriptors
4815 for reading symbols from object files and libraries. This was
4816 especially a problem for programs that used many (~100) shared
4819 The `step' command now only enters a subroutine if there is line number
4820 information for the subroutine. Otherwise it acts like the `next'
4821 command. Previously, `step' would enter subroutines if there was
4822 any debugging information about the routine. This avoids problems
4823 when using `cc -g1' on MIPS machines.
4825 * Internal improvements
4827 GDB's internal interfaces have been improved to make it easier to support
4828 debugging of multiple languages in the future.
4830 GDB now uses a common structure for symbol information internally.
4831 Minimal symbols (derived from linkage symbols in object files), partial
4832 symbols (from a quick scan of debug information), and full symbols
4833 contain a common subset of information, making it easier to write
4834 shared code that handles any of them.
4836 * New command line options
4838 We now accept --silent as an alias for --quiet.
4842 The memory-mapped-malloc library is now licensed under the GNU Library
4843 General Public License.
4845 *** Changes in GDB-4.7:
4847 * Host/native/target split
4849 GDB has had some major internal surgery to untangle the support for
4850 hosts and remote targets. Now, when you configure GDB for a remote
4851 target, it will no longer load in all of the support for debugging
4852 local programs on the host. When fully completed and tested, this will
4853 ensure that arbitrary host/target combinations are possible.
4855 The primary conceptual shift is to separate the non-portable code in
4856 GDB into three categories. Host specific code is required any time GDB
4857 is compiled on that host, regardless of the target. Target specific
4858 code relates to the peculiarities of the target, but can be compiled on
4859 any host. Native specific code is everything else: it can only be
4860 built when the host and target are the same system. Child process
4861 handling and core file support are two common `native' examples.
4863 GDB's use of /proc for controlling Unix child processes is now cleaner.
4864 It has been split out into a single module under the `target_ops' vector,
4865 plus two native-dependent functions for each system that uses /proc.
4867 * New hosts supported
4869 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4870 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4871 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4873 * New targets supported
4875 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4876 68030 and CPU32 m68030-*-*, m68332-*-*
4878 * New native hosts supported
4880 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4881 (386bsd is not well tested yet)
4882 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4884 * New file formats supported
4886 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4887 supports reading of `a.out.adobe' object files, which are an a.out
4888 format extended with minimal information about multiple sections.
4892 `show copying' is the same as the old `info copying'.
4893 `show warranty' is the same as `info warrantee'.
4894 These were renamed for consistency. The old commands continue to work.
4896 `info handle' is a new alias for `info signals'.
4898 You can now define pre-command hooks, which attach arbitrary command
4899 scripts to any command. The commands in the hook will be executed
4900 prior to the user's command. You can also create a hook which will be
4901 executed whenever the program stops. See gdb.texinfo.
4905 We now deal with Cfront style name mangling, and can even extract type
4906 info from mangled symbols. GDB can automatically figure out which
4907 symbol mangling style your C++ compiler uses.
4909 Calling of methods and virtual functions has been improved as well.
4913 The crash that occured when debugging Sun Ansi-C compiled binaries is
4914 fixed. This was due to mishandling of the extra N_SO stabs output
4917 We also finally got Ultrix 4.2 running in house, and fixed core file
4918 support, with help from a dozen people on the net.
4920 John M. Farrell discovered that the reason that single-stepping was so
4921 slow on all of the Mips based platforms (primarily SGI and DEC) was
4922 that we were trying to demangle and lookup a symbol used for internal
4923 purposes on every instruction that was being stepped through. Changing
4924 the name of that symbol so that it couldn't be mistaken for a C++
4925 mangled symbol sped things up a great deal.
4927 Rich Pixley sped up symbol lookups in general by getting much smarter
4928 about when C++ symbol mangling is necessary. This should make symbol
4929 completion (TAB on the command line) much faster. It's not as fast as
4930 we'd like, but it's significantly faster than gdb-4.6.
4934 A new user controllable variable 'call_scratch_address' can
4935 specify the location of a scratch area to be used when GDB
4936 calls a function in the target. This is necessary because the
4937 usual method of putting the scratch area on the stack does not work
4938 in systems that have separate instruction and data spaces.
4940 We integrated changes to support the 29k UDI (Universal Debugger
4941 Interface), but discovered at the last minute that we didn't have all
4942 of the appropriate copyright paperwork. We are working with AMD to
4943 resolve this, and hope to have it available soon.
4947 We have sped up the remote serial line protocol, especially for targets
4948 with lots of registers. It now supports a new `expedited status' ('T')
4949 message which can be used in place of the existing 'S' status message.
4950 This allows the remote stub to send only the registers that GDB
4951 needs to make a quick decision about single-stepping or conditional
4952 breakpoints, eliminating the need to fetch the entire register set for
4953 each instruction being stepped through.
4955 The GDB remote serial protocol now implements a write-through cache for
4956 registers, only re-reading the registers if the target has run.
4958 There is also a new remote serial stub for SPARC processors. You can
4959 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4960 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4961 processor with a serial port.
4965 Configure.in files have become much easier to read and modify. A new
4966 `table driven' format makes it more obvious what configurations are
4967 supported, and what files each one uses.
4971 There is a new opcodes library which will eventually contain all of the
4972 disassembly routines and opcode tables. At present, it only contains
4973 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4974 disassembler (binutils/objdump) to share these routines.
4976 The libiberty library is now copylefted under the GNU Library General
4977 Public License. This allows more liberal use, and was done so libg++
4978 can use it. This makes no difference to GDB, since the Library License
4979 grants all the rights from the General Public License.
4983 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4984 reference to the stabs symbol info used by the debugger. It is (as far
4985 as we know) the only published document on this fascinating topic. We
4986 encourage you to read it, compare it to the stabs information on your
4987 system, and send improvements on the document in general (to
4988 bug-gdb@prep.ai.mit.edu).
4990 And, of course, many bugs have been fixed.
4993 *** Changes in GDB-4.6:
4995 * Better support for C++ function names
4997 GDB now accepts as input the "demangled form" of C++ overloaded function
4998 names and member function names, and can do command completion on such names
4999 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5000 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5001 Make use of command completion, it is your friend.
5003 GDB also now accepts a variety of C++ mangled symbol formats. They are
5004 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5005 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5006 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5007 for the list of formats.
5009 * G++ symbol mangling problem
5011 Recent versions of gcc have a bug in how they emit debugging information for
5012 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5013 directory) can be applied to gcc to fix the problem. Alternatively, if you
5014 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5015 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5016 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5019 * New 'maintenance' command
5021 All of the commands related to hacking GDB internals have been moved out of
5022 the main command set, and now live behind the 'maintenance' command. This
5023 can also be abbreviated as 'mt'. The following changes were made:
5025 dump-me -> maintenance dump-me
5026 info all-breakpoints -> maintenance info breakpoints
5027 printmsyms -> maintenance print msyms
5028 printobjfiles -> maintenance print objfiles
5029 printpsyms -> maintenance print psymbols
5030 printsyms -> maintenance print symbols
5032 The following commands are new:
5034 maintenance demangle Call internal GDB demangler routine to
5035 demangle a C++ link name and prints the result.
5036 maintenance print type Print a type chain for a given symbol
5038 * Change to .gdbinit file processing
5040 We now read the $HOME/.gdbinit file before processing the argv arguments
5041 (e.g. reading symbol files or core files). This allows global parameters to
5042 be set, which will apply during the symbol reading. The ./.gdbinit is still
5043 read after argv processing.
5045 * New hosts supported
5047 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5049 GNU/Linux support i386-unknown-linux or linux
5051 We are also including code to support the HP/PA running BSD and HPUX. This
5052 is almost guaranteed not to work, as we didn't have time to test or build it
5053 for this release. We are including it so that the more adventurous (or
5054 masochistic) of you can play with it. We also had major problems with the
5055 fact that the compiler that we got from HP doesn't support the -g option.
5058 * New targets supported
5060 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5062 * More smarts about finding #include files
5064 GDB now remembers the compilation directory for all include files, and for
5065 all files from which C is generated (like yacc and lex sources). This
5066 greatly improves GDB's ability to find yacc/lex sources, and include files,
5067 especially if you are debugging your program from a directory different from
5068 the one that contains your sources.
5070 We also fixed a bug which caused difficulty with listing and setting
5071 breakpoints in include files which contain C code. (In the past, you had to
5072 try twice in order to list an include file that you hadn't looked at before.)
5074 * Interesting infernals change
5076 GDB now deals with arbitrary numbers of sections, where the symbols for each
5077 section must be relocated relative to that section's landing place in the
5078 target's address space. This work was needed to support ELF with embedded
5079 stabs used by Solaris-2.0.
5081 * Bug fixes (of course!)
5083 There have been loads of fixes for the following things:
5084 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5085 i960, stabs, DOS(GO32), procfs, etc...
5087 See the ChangeLog for details.
5089 *** Changes in GDB-4.5:
5091 * New machines supported (host and target)
5093 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5095 SGI Irix-4.x mips-sgi-irix4 or iris4
5097 * New malloc package
5099 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5100 Mmalloc is capable of handling mutiple heaps of memory. It is also
5101 capable of saving a heap to a file, and then mapping it back in later.
5102 This can be used to greatly speedup the startup of GDB by using a
5103 pre-parsed symbol table which lives in a mmalloc managed heap. For
5104 more details, please read mmalloc/mmalloc.texi.
5108 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5109 'help info proc' for details.
5111 * MIPS ecoff symbol table format
5113 The code that reads MIPS symbol table format is now supported on all hosts.
5114 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5117 * File name changes for MS-DOS
5119 Many files in the config directories have been renamed to make it easier to
5120 support GDB on MS-DOSe systems (which have very restrictive file name
5121 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5122 environment) is close to working but has some remaining problems. Note
5123 that debugging of DOS programs is not supported, due to limitations
5124 in the ``operating system'', but it can be used to host cross-debugging.
5126 * Cross byte order fixes
5128 Many fixes have been made to support cross debugging of Sparc and MIPS
5129 targets from hosts whose byte order differs.
5131 * New -mapped and -readnow options
5133 If memory-mapped files are available on your system through the 'mmap'
5134 system call, you can use the -mapped option on the `file' or
5135 `symbol-file' commands to cause GDB to write the symbols from your
5136 program into a reusable file. If the program you are debugging is
5137 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5138 Future GDB debugging sessions will notice the presence of this file,
5139 and will quickly map in symbol information from it, rather than reading
5140 the symbol table from the executable program. Using the '-mapped'
5141 option in a GDB `file' or `symbol-file' command has the same effect as
5142 starting GDB with the '-mapped' command-line option.
5144 You can cause GDB to read the entire symbol table immediately by using
5145 the '-readnow' option with any of the commands that load symbol table
5146 information (or on the GDB command line). This makes the command
5147 slower, but makes future operations faster.
5149 The -mapped and -readnow options are typically combined in order to
5150 build a `fred.syms' file that contains complete symbol information.
5151 A simple GDB invocation to do nothing but build a `.syms' file for future
5154 gdb -batch -nx -mapped -readnow programname
5156 The `.syms' file is specific to the host machine on which GDB is run.
5157 It holds an exact image of GDB's internal symbol table. It cannot be
5158 shared across multiple host platforms.
5160 * longjmp() handling
5162 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5163 siglongjmp() without losing control. This feature has not yet been ported to
5164 all systems. It currently works on many 386 platforms, all MIPS-based
5165 platforms (SGI, DECstation, etc), and Sun3/4.
5169 Preliminary work has been put in to support the new Solaris OS from Sun. At
5170 this time, it can control and debug processes, but it is not capable of
5175 As always, many many bug fixes. The major areas were with g++, and mipsread.
5176 People using the MIPS-based platforms should experience fewer mysterious
5177 crashes and trashed symbol tables.
5179 *** Changes in GDB-4.4:
5181 * New machines supported (host and target)
5183 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5185 BSD Reno on Vax vax-dec-bsd
5186 Ultrix on Vax vax-dec-ultrix
5188 * New machines supported (target)
5190 AMD 29000 embedded, using EBMON a29k-none-none
5194 GDB continues to improve its handling of C++. `References' work better.
5195 The demangler has also been improved, and now deals with symbols mangled as
5196 per the Annotated C++ Reference Guide.
5198 GDB also now handles `stabs' symbol information embedded in MIPS
5199 `ecoff' symbol tables. Since the ecoff format was not easily
5200 extensible to handle new languages such as C++, this appeared to be a
5201 good way to put C++ debugging info into MIPS binaries. This option
5202 will be supported in the GNU C compiler, version 2, when it is
5205 * New features for SVR4
5207 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5208 shared libraries. Debugging dynamically linked programs should present
5209 only minor differences from debugging statically linked programs.
5211 The `info proc' command will print out information about any process
5212 on an SVR4 system (including the one you are debugging). At the moment,
5213 it prints the address mappings of the process.
5215 If you bring up GDB on another SVR4 system, please send mail to
5216 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5218 * Better dynamic linking support in SunOS
5220 Reading symbols from shared libraries which contain debugging symbols
5221 now works properly. However, there remain issues such as automatic
5222 skipping of `transfer vector' code during function calls, which
5223 make it harder to debug code in a shared library, than to debug the
5224 same code linked statically.
5228 GDB is now using the latest `getopt' routines from the FSF. This
5229 version accepts the -- prefix for options with long names. GDB will
5230 continue to accept the old forms (-option and +option) as well.
5231 Various single letter abbreviations for options have been explicity
5232 added to the option table so that they won't get overshadowed in the
5233 future by other options that begin with the same letter.
5237 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5238 Many assorted bugs have been handled. Many more remain to be handled.
5239 See the various ChangeLog files (primarily in gdb and bfd) for details.
5242 *** Changes in GDB-4.3:
5244 * New machines supported (host and target)
5246 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5247 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5248 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5250 * Almost SCO Unix support
5252 We had hoped to support:
5253 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5254 (except for core file support), but we discovered very late in the release
5255 that it has problems with process groups that render gdb unusable. Sorry
5256 about that. I encourage people to fix it and post the fixes.
5258 * Preliminary ELF and DWARF support
5260 GDB can read ELF object files on System V Release 4, and can handle
5261 debugging records for C, in DWARF format, in ELF files. This support
5262 is preliminary. If you bring up GDB on another SVR4 system, please
5263 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5268 GDB now uses the latest `readline' library. One user-visible change
5269 is that two tabs will list possible command completions, which previously
5270 required typing M-? (meta-question mark, or ESC ?).
5274 The `stepi' bug that many of you noticed has been squashed.
5275 Many bugs in C++ have been handled. Many more remain to be handled.
5276 See the various ChangeLog files (primarily in gdb and bfd) for details.
5278 * State of the MIPS world (in case you wondered):
5280 GDB can understand the symbol tables emitted by the compilers
5281 supplied by most vendors of MIPS-based machines, including DEC. These
5282 symbol tables are in a format that essentially nobody else uses.
5284 Some versions of gcc come with an assembler post-processor called
5285 mips-tfile. This program is required if you want to do source-level
5286 debugging of gcc-compiled programs. I believe FSF does not ship
5287 mips-tfile with gcc version 1, but it will eventually come with gcc
5290 Debugging of g++ output remains a problem. g++ version 1.xx does not
5291 really support it at all. (If you're lucky, you should be able to get
5292 line numbers and stack traces to work, but no parameters or local
5293 variables.) With some work it should be possible to improve the
5296 When gcc version 2 is released, you will have somewhat better luck.
5297 However, even then you will get confusing results for inheritance and
5300 We will eventually provide full debugging of g++ output on
5301 DECstations. This will probably involve some kind of stabs-in-ecoff
5302 encapulation, but the details have not been worked out yet.
5305 *** Changes in GDB-4.2:
5307 * Improved configuration
5309 Only one copy of `configure' exists now, and it is not self-modifying.
5310 Porting BFD is simpler.
5314 The `step' and `next' commands now only stop at the first instruction
5315 of a source line. This prevents the multiple stops that used to occur
5316 in switch statements, for-loops, etc. `Step' continues to stop if a
5317 function that has debugging information is called within the line.
5321 Lots of small bugs fixed. More remain.
5323 * New host supported (not target)
5325 Intel 386 PC clone running Mach i386-none-mach
5328 *** Changes in GDB-4.1:
5330 * Multiple source language support
5332 GDB now has internal scaffolding to handle several source languages.
5333 It determines the type of each source file from its filename extension,
5334 and will switch expression parsing and number formatting to match the
5335 language of the function in the currently selected stack frame.
5336 You can also specifically set the language to be used, with
5337 `set language c' or `set language modula-2'.
5341 GDB now has preliminary support for the GNU Modula-2 compiler,
5342 currently under development at the State University of New York at
5343 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5344 continue through the fall of 1991 and into 1992.
5346 Other Modula-2 compilers are currently not supported, and attempting to
5347 debug programs compiled with them will likely result in an error as the
5348 symbol table is read. Feel free to work on it, though!
5350 There are hooks in GDB for strict type checking and range checking,
5351 in the `Modula-2 philosophy', but they do not currently work.
5355 GDB can now write to executable and core files (e.g. patch
5356 a variable's value). You must turn this switch on, specify
5357 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5358 by assigning a new value to a variable. Modifications take
5361 * Automatic SunOS shared library reading
5363 When you run your program, GDB automatically determines where its
5364 shared libraries (if any) have been loaded, and reads their symbols.
5365 The `share' command is no longer needed. This also works when
5366 examining core files.
5370 You can specify the number of lines that the `list' command shows.
5373 * New machines supported (host and target)
5375 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5376 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5377 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5379 * New hosts supported (not targets)
5381 IBM RT/PC: romp-ibm-aix or rtpc
5383 * New targets supported (not hosts)
5385 AMD 29000 embedded with COFF a29k-none-coff
5386 AMD 29000 embedded with a.out a29k-none-aout
5387 Ultracomputer remote kernel debug a29k-nyu-kern
5389 * New remote interfaces
5395 *** Changes in GDB-4.0:
5399 Wide output is wrapped at good places to make the output more readable.
5401 Gdb now supports cross-debugging from a host machine of one type to a
5402 target machine of another type. Communication with the target system
5403 is over serial lines. The ``target'' command handles connecting to the
5404 remote system; the ``load'' command will download a program into the
5405 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5406 also supports debugging of realtime processes running under VxWorks,
5407 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5408 stub on the target system.
5410 New CPUs supported include the AMD 29000 and Intel 960.
5412 GDB now reads object files and symbol tables via a ``binary file''
5413 library, which allows a single copy of GDB to debug programs of multiple
5414 object file types such as a.out and coff.
5416 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5417 refcard.dvi and refcard.ps are available to format it).
5420 * Control-Variable user interface simplified
5422 All variables that control the operation of the debugger can be set
5423 by the ``set'' command, and displayed by the ``show'' command.
5425 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5426 ``Show prompt'' produces the response:
5427 Gdb's prompt is new-gdb=>.
5429 What follows are the NEW set commands. The command ``help set'' will
5430 print a complete list of old and new set commands. ``help set FOO''
5431 will give a longer description of the variable FOO. ``show'' will show
5432 all of the variable descriptions and their current settings.
5434 confirm on/off: Enables warning questions for operations that are
5435 hard to recover from, e.g. rerunning the program while
5436 it is already running. Default is ON.
5438 editing on/off: Enables EMACS style command line editing
5439 of input. Previous lines can be recalled with
5440 control-P, the current line can be edited with control-B,
5441 you can search for commands with control-R, etc.
5444 history filename NAME: NAME is where the gdb command history
5445 will be stored. The default is .gdb_history,
5446 or the value of the environment variable
5449 history size N: The size, in commands, of the command history. The
5450 default is 256, or the value of the environment variable
5453 history save on/off: If this value is set to ON, the history file will
5454 be saved after exiting gdb. If set to OFF, the
5455 file will not be saved. The default is OFF.
5457 history expansion on/off: If this value is set to ON, then csh-like
5458 history expansion will be performed on
5459 command line input. The default is OFF.
5461 radix N: Sets the default radix for input and output. It can be set
5462 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5463 in the current radix, so "set radix 10" is always a no-op.
5465 height N: This integer value is the number of lines on a page. Default
5466 is 24, the current `stty rows'' setting, or the ``li#''
5467 setting from the termcap entry matching the environment
5470 width N: This integer value is the number of characters on a line.
5471 Default is 80, the current `stty cols'' setting, or the ``co#''
5472 setting from the termcap entry matching the environment
5475 Note: ``set screensize'' is obsolete. Use ``set height'' and
5476 ``set width'' instead.
5478 print address on/off: Print memory addresses in various command displays,
5479 such as stack traces and structure values. Gdb looks
5480 more ``symbolic'' if you turn this off; it looks more
5481 ``machine level'' with it on. Default is ON.
5483 print array on/off: Prettyprint arrays. New convenient format! Default
5486 print demangle on/off: Print C++ symbols in "source" form if on,
5489 print asm-demangle on/off: Same, for assembler level printouts
5492 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5495 * Support for Epoch Environment.
5497 The epoch environment is a version of Emacs v18 with windowing. One
5498 new command, ``inspect'', is identical to ``print'', except that if you
5499 are running in the epoch environment, the value is printed in its own
5503 * Support for Shared Libraries
5505 GDB can now debug programs and core files that use SunOS shared libraries.
5506 Symbols from a shared library cannot be referenced
5507 before the shared library has been linked with the program (this
5508 happens after you type ``run'' and before the function main() is entered).
5509 At any time after this linking (including when examining core files
5510 from dynamically linked programs), gdb reads the symbols from each
5511 shared library when you type the ``sharedlibrary'' command.
5512 It can be abbreviated ``share''.
5514 sharedlibrary REGEXP: Load shared object library symbols for files
5515 matching a unix regular expression. No argument
5516 indicates to load symbols for all shared libraries.
5518 info sharedlibrary: Status of loaded shared libraries.
5523 A watchpoint stops execution of a program whenever the value of an
5524 expression changes. Checking for this slows down execution
5525 tremendously whenever you are in the scope of the expression, but is
5526 quite useful for catching tough ``bit-spreader'' or pointer misuse
5527 problems. Some machines such as the 386 have hardware for doing this
5528 more quickly, and future versions of gdb will use this hardware.
5530 watch EXP: Set a watchpoint (breakpoint) for an expression.
5532 info watchpoints: Information about your watchpoints.
5534 delete N: Deletes watchpoint number N (same as breakpoints).
5535 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5536 enable N: Re-enables watchpoint number N (same as breakpoints).
5539 * C++ multiple inheritance
5541 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5544 * C++ exception handling
5546 Gdb now supports limited C++ exception handling. Besides the existing
5547 ability to breakpoint on an exception handler, gdb can breakpoint on
5548 the raising of an exception (before the stack is peeled back to the
5551 catch FOO: If there is a FOO exception handler in the dynamic scope,
5552 set a breakpoint to catch exceptions which may be raised there.
5553 Multiple exceptions (``catch foo bar baz'') may be caught.
5555 info catch: Lists all exceptions which may be caught in the
5556 current stack frame.
5559 * Minor command changes
5561 The command ``call func (arg, arg, ...)'' now acts like the print
5562 command, except it does not print or save a value if the function's result
5563 is void. This is similar to dbx usage.
5565 The ``up'' and ``down'' commands now always print the frame they end up
5566 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5567 frames without printing.
5569 * New directory command
5571 'dir' now adds directories to the FRONT of the source search path.
5572 The path starts off empty. Source files that contain debug information
5573 about the directory in which they were compiled can be found even
5574 with an empty path; Sun CC and GCC include this information. If GDB can't
5575 find your source file in the current directory, type "dir .".
5577 * Configuring GDB for compilation
5579 For normal use, type ``./configure host''. See README or gdb.texinfo
5582 GDB now handles cross debugging. If you are remotely debugging between
5583 two different machines, type ``./configure host -target=targ''.
5584 Host is the machine where GDB will run; targ is the machine
5585 where the program that you are debugging will run.
5587 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.