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.
47 ** New attribute 'name' for gdb.Type objects.
51 Nios II ELF nios2*-*-elf
52 Nios II GNU/Linux nios2*-*-linux
53 Texas Instruments MSP430 msp430*-*-elf
55 * Removed native configurations
57 Support for these a.out NetBSD and OpenBSD obsolete configurations has
58 been removed. ELF variants of these configurations are kept supported.
60 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
61 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
62 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
63 i[34567]86-*-openbsd3.[0-3]
64 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
65 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
66 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
70 Like "catch throw", but catches a re-thrown exception.
72 Renamed from old "maint check-symtabs".
74 Perform consistency checks on symtabs.
76 Expand symtabs matching an optional regexp.
79 Display the details of GDB configure-time options.
81 maint set|show per-command
82 maint set|show per-command space
83 maint set|show per-command time
84 maint set|show per-command symtab
85 Enable display of per-command gdb resource usage.
87 remove-symbol-file FILENAME
88 remove-symbol-file -a ADDRESS
89 Remove a symbol file added via add-symbol-file. The file to remove
90 can be identified by its filename or by an address that lies within
91 the boundaries of this symbol file in memory.
94 info exceptions REGEXP
95 Display the list of Ada exceptions defined in the program being
96 debugged. If provided, only the exceptions whose names match REGEXP
101 set debug symfile off|on
103 Control display of debugging info regarding reading symbol files and
104 symbol tables within those files
106 set print raw frame-arguments
107 show print raw frame-arguments
108 Set/show whether to print frame arguments in raw mode,
109 disregarding any defined pretty-printers.
111 set remote trace-status-packet
112 show remote trace-status-packet
113 Set/show the use of remote protocol qTStatus packet.
117 Control display of debugging messages related to Nios II targets.
121 Control whether target-assisted range stepping is enabled.
123 set startup-with-shell
124 show startup-with-shell
125 Specifies whether Unix child processes are started via a shell or
130 Use the target memory cache for accesses to the code segment. This
131 improves performance of remote debugging (particularly disassembly).
133 * You can now use a literal value 'unlimited' for options that
134 interpret 0 or -1 as meaning "unlimited". E.g., "set
135 trace-buffer-size unlimited" is now an alias for "set
136 trace-buffer-size -1" and "set height unlimited" is now an alias for
139 * The "set debug symtab-create" debugging option of GDB has been changed to
140 accept a verbosity level. 0 means "off", 1 provides basic debugging
141 output, and values of 2 or greater provides more verbose output.
143 * New command-line options
145 Display the details of GDB configure-time options.
147 * The command 'tsave' can now support new option '-ctf' to save trace
148 buffer in Common Trace Format.
150 * Newly installed $prefix/bin/gcore acts as a shell interface for the
153 * GDB now implements the the C++ 'typeid' operator.
155 * The new convenience variable $_exception holds the exception being
156 thrown or caught at an exception-related catchpoint.
158 * The exception-related catchpoints, like "catch throw", now accept a
159 regular expression which can be used to filter exceptions by type.
161 * The new convenience variable $_exitsignal is automatically set to
162 the terminating signal number when the program being debugged dies
163 due to an uncaught signal.
167 ** All MI commands now accept an optional "--language" option.
168 Support for this feature can be verified by using the "-list-features"
169 command, which should contain "language-option".
171 ** The new command -info-gdb-mi-command allows the user to determine
172 whether a GDB/MI command is supported or not.
174 ** The "^error" result record returned when trying to execute an undefined
175 GDB/MI command now provides a variable named "code" whose content is the
176 "undefined-command" error code. Support for this feature can be verified
177 by using the "-list-features" command, which should contain
178 "undefined-command-error-code".
180 ** The -trace-save MI command can optionally save trace buffer in Common
183 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
185 ** The command -data-list-register-values now accepts an optional
186 "--skip-unavailable" option. When used, only the available registers
189 ** The new command -trace-frame-collected dumps collected variables,
190 computed expressions, tvars, memory and registers in a traceframe.
192 ** The commands -stack-list-locals, -stack-list-arguments and
193 -stack-list-variables now accept an option "--skip-unavailable".
194 When used, only the available locals or arguments are displayed.
196 ** The -exec-run command now accepts an optional "--start" option.
197 When used, the command follows the same semantics as the "start"
198 command, stopping the program's execution at the start of its
199 main subprogram. Support for this feature can be verified using
200 the "-list-features" command, which should contain
201 "exec-run-start-option".
203 ** The new commands -catch-assert and -catch-exceptions insert
204 catchpoints stopping the program when Ada exceptions are raised.
206 ** The new command -info-ada-exceptions provides the equivalent of
207 the new "info exceptions" command.
209 * New system-wide configuration scripts
210 A GDB installation now provides scripts suitable for use as system-wide
211 configuration scripts for the following systems:
215 * GDB now supports target-assigned range stepping with remote targets.
216 This improves the performance of stepping source lines by reducing
217 the number of control packets from/to GDB. See "New remote packets"
220 * GDB now understands the element 'tvar' in the XML traceframe info.
221 It has the id of the collected trace state variables.
223 * On S/390 targets that provide the transactional-execution feature,
224 the program interruption transaction diagnostic block (TDB) is now
225 represented as a number of additional "registers" in GDB.
231 The vCont packet supports a new 'r' action, that tells the remote
232 stub to step through an address range itself, without GDB
233 involvemement at each single-step.
235 qXfer:libraries-svr4:read's annex
236 The previously unused annex of the qXfer:libraries-svr4:read packet
237 is now used to support passing an argument list. The remote stub
238 reports support for this argument list to GDB's qSupported query.
239 The defined arguments are "start" and "prev", used to reduce work
240 necessary for library list updating, resulting in significant
243 * New features in the GDB remote stub, GDBserver
245 ** GDBserver now supports target-assisted range stepping. Currently
246 enabled on x86/x86_64 GNU/Linux targets.
248 ** GDBserver now adds element 'tvar' in the XML in the reply to
249 'qXfer:traceframe-info:read'. It has the id of the collected
250 trace state variables.
252 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
255 * New 'z' formatter for printing and examining memory, this displays the
256 value as hexadecimal zero padded on the left to the size of the type.
258 * GDB can now use Windows x64 unwinding data.
260 * The "set remotebaud" command has been replaced by "set serial baud".
261 Similarly, "show remotebaud" has been replaced by "show serial baud".
262 The "set remotebaud" and "show remotebaud" commands are still available
263 to provide backward compatibility with older versions of GDB.
265 *** Changes in GDB 7.6
267 * Target record has been renamed to record-full.
268 Record/replay is now enabled with the "record full" command.
269 This also affects settings that are associated with full record/replay
270 that have been moved from "set/show record" to "set/show record full":
272 set|show record full insn-number-max
273 set|show record full stop-at-limit
274 set|show record full memory-query
276 * A new record target "record-btrace" has been added. The new target
277 uses hardware support to record the control-flow of a process. It
278 does not support replaying the execution, but it implements the
279 below new commands for investigating the recorded execution log.
280 This new recording method can be enabled using:
284 The "record-btrace" target is only available on Intel Atom processors
285 and requires a Linux kernel 2.6.32 or later.
287 * Two new commands have been added for record/replay to give information
288 about the recorded execution without having to replay the execution.
289 The commands are only supported by "record btrace".
291 record instruction-history prints the execution history at
292 instruction granularity
294 record function-call-history prints the execution history at
297 * New native configurations
299 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
300 FreeBSD/powerpc powerpc*-*-freebsd
301 x86_64/Cygwin x86_64-*-cygwin*
302 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
306 ARM AArch64 aarch64*-*-elf
307 ARM AArch64 GNU/Linux aarch64*-*-linux
308 Lynx 178 PowerPC powerpc-*-lynx*178
309 x86_64/Cygwin x86_64-*-cygwin*
310 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
312 * If the configured location of system.gdbinit file (as given by the
313 --with-system-gdbinit option at configure time) is in the
314 data-directory (as specified by --with-gdb-datadir at configure
315 time) or in one of its subdirectories, then GDB will look for the
316 system-wide init file in the directory specified by the
317 --data-directory command-line option.
319 * New command line options:
321 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
322 other initialization files, unlike -nx which disables all of them.
324 * Removed command line options
326 -epoch This was used by the gdb mode in Epoch, an ancient fork of
329 * The 'ptype' and 'whatis' commands now accept an argument to control
332 * 'info proc' now works on some core files.
336 ** Vectors can be created with gdb.Type.vector.
338 ** Python's atexit.register now works in GDB.
340 ** Types can be pretty-printed via a Python API.
342 ** Python 3 is now supported (in addition to Python 2.4 or later)
344 ** New class gdb.Architecture exposes GDB's internal representation
345 of architecture in the Python API.
347 ** New method Frame.architecture returns the gdb.Architecture object
348 corresponding to the frame's architecture.
350 * New Python-based convenience functions:
352 ** $_memeq(buf1, buf2, length)
353 ** $_streq(str1, str2)
355 ** $_regex(str, regex)
357 * The 'cd' command now defaults to using '~' (the home directory) if not
360 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
361 default for GCC since November 2000.
363 * The command 'forward-search' can now be abbreviated as 'fo'.
365 * The command 'info tracepoints' can now display 'installed on target'
366 or 'not installed on target' for each non-pending location of tracepoint.
368 * New configure options
370 --enable-libmcheck/--disable-libmcheck
371 By default, development versions are built with -lmcheck on hosts
372 that support it, in order to help track memory corruption issues.
373 Release versions, on the other hand, are built without -lmcheck
374 by default. The --enable-libmcheck/--disable-libmcheck configure
375 options allow the user to override that default.
376 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
377 This configure option allows the user to build GDB with
378 libbabeltrace using which GDB can read Common Trace Format data.
380 * New commands (for set/show, see "New options" below)
383 Catch signals. This is similar to "handle", but allows commands and
384 conditions to be attached.
387 List the BFDs known to GDB.
389 python-interactive [command]
391 Start a Python interactive prompt, or evaluate the optional command
392 and print the result of expressions.
395 "py" is a new alias for "python".
397 enable type-printer [name]...
398 disable type-printer [name]...
399 Enable or disable type printers.
403 ** For the Renesas Super-H architecture, the "regs" command has been removed
404 (has been deprecated in GDB 7.5), and "info all-registers" should be used
409 set print type methods (on|off)
410 show print type methods
411 Control whether method declarations are displayed by "ptype".
412 The default is to show them.
414 set print type typedefs (on|off)
415 show print type typedefs
416 Control whether typedef definitions are displayed by "ptype".
417 The default is to show them.
419 set filename-display basename|relative|absolute
420 show filename-display
421 Control the way in which filenames is displayed.
422 The default is "relative", which preserves previous behavior.
424 set trace-buffer-size
425 show trace-buffer-size
426 Request target to change the size of trace buffer.
428 set remote trace-buffer-size-packet auto|on|off
429 show remote trace-buffer-size-packet
430 Control the use of the remote protocol `QTBuffer:size' packet.
434 Control display of debugging messages related to ARM AArch64.
437 set debug coff-pe-read
438 show debug coff-pe-read
439 Control display of debugging messages related to reading of COFF/PE
444 Control display of debugging messages related to Mach-O symbols
447 set debug notification
448 show debug notification
449 Control display of debugging info for async remote notification.
453 ** Command parameter changes are now notified using new async record
454 "=cmd-param-changed".
455 ** Trace frame changes caused by command "tfind" are now notified using
456 new async record "=traceframe-changed".
457 ** The creation, deletion and modification of trace state variables
458 are now notified using new async records "=tsv-created",
459 "=tsv-deleted" and "=tsv-modified".
460 ** The start and stop of process record are now notified using new
461 async record "=record-started" and "=record-stopped".
462 ** Memory changes are now notified using new async record
464 ** The data-disassemble command response will include a "fullname" field
465 containing the absolute file name when source has been requested.
466 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
467 command, to allow pattern filling of memory areas.
468 ** New commands "-catch-load"/"-catch-unload" added for intercepting
469 library load/unload events.
470 ** The response to breakpoint commands and breakpoint async records
471 includes an "installed" field containing a boolean state about each
472 non-pending tracepoint location is whether installed on target or not.
473 ** Output of the "-trace-status" command includes a "trace-file" field
474 containing the name of the trace file being examined. This field is
475 optional, and only present when examining a trace file.
476 ** The "fullname" field is now always present along with the "file" field,
477 even if the file cannot be found by GDB.
479 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
480 You must have the LZMA library available when configuring GDB for this
481 feature to be enabled. For more information, see:
482 http://fedoraproject.org/wiki/Features/MiniDebugInfo
487 Set the size of trace buffer. The remote stub reports support for this
488 packet to gdb's qSupported query.
491 Enable Branch Trace Store (BTS)-based branch tracing for the current
492 thread. The remote stub reports support for this packet to gdb's
496 Disable branch tracing for the current thread. The remote stub reports
497 support for this packet to gdb's qSupported query.
500 Read the traced branches for the current thread. The remote stub
501 reports support for this packet to gdb's qSupported query.
503 *** Changes in GDB 7.5
505 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
506 for more x32 ABI info.
508 * GDB now supports access to MIPS DSP registers on Linux targets.
510 * GDB now supports debugging microMIPS binaries.
512 * The "info os" command on GNU/Linux can now display information on
513 several new classes of objects managed by the operating system:
514 "info os procgroups" lists process groups
515 "info os files" lists file descriptors
516 "info os sockets" lists internet-domain sockets
517 "info os shm" lists shared-memory regions
518 "info os semaphores" lists semaphores
519 "info os msg" lists message queues
520 "info os modules" lists loaded kernel modules
522 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
523 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
524 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
525 options and inspect the probe arguments using the new $_probe_arg family
526 of convenience variables. You can obtain more information about SystemTap
527 in <http://sourceware.org/systemtap/>.
529 * GDB now supports reversible debugging on ARM, it allows you to
530 debug basic ARM and THUMB instructions, and provides
531 record/replay support.
533 * The option "symbol-reloading" has been deleted as it is no longer used.
537 ** GDB commands implemented in Python can now be put in command class
540 ** The "maint set python print-stack on|off" is now deleted.
542 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
543 apply "flag enum"-style pretty-printing to any enum.
545 ** gdb.lookup_symbol can now work when there is no current frame.
547 ** gdb.Symbol now has a 'line' attribute, holding the line number in
548 the source at which the symbol was defined.
550 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
551 method 'value'. The former indicates whether the symbol needs a
552 frame in order to compute its value, and the latter computes the
555 ** A new method 'referenced_value' on gdb.Value objects which can
556 dereference pointer as well as C++ reference values.
558 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
559 which return the global and static blocks (as gdb.Block objects),
560 of the underlying symbol table, respectively.
562 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
563 object associated with a PC value.
565 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
566 of the address range occupied by code for the current source line.
568 * Go language support.
569 GDB now supports debugging programs written in the Go programming
572 * GDBserver now supports stdio connections.
573 E.g. (gdb) target remote | ssh myhost gdbserver - hello
575 * The binary "gdbtui" can no longer be built or installed.
576 Use "gdb -tui" instead.
578 * GDB will now print "flag" enums specially. A flag enum is one where
579 all the enumerator values have no bits in common when pairwise
580 "and"ed. When printing a value whose type is a flag enum, GDB will
581 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
582 (gdb) print (enum E) 3
585 * The filename part of a linespec will now match trailing components
586 of a source file name. For example, "break gcc/expr.c:1000" will
587 now set a breakpoint in build/gcc/expr.c, but not
590 * The "info proc" and "generate-core-file" commands will now also
591 work on remote targets connected to GDBserver on Linux.
593 * The command "info catch" has been removed. It has been disabled
596 * The "catch exception" and "catch assert" commands now accept
597 a condition at the end of the command, much like the "break"
598 command does. For instance:
600 (gdb) catch exception Constraint_Error if Barrier = True
602 Previously, it was possible to add a condition to such catchpoints,
603 but it had to be done as a second step, after the catchpoint had been
604 created, using the "condition" command.
606 * The "info static-tracepoint-marker" command will now also work on
607 native Linux targets with in-process agent.
609 * GDB can now set breakpoints on inlined functions.
611 * The .gdb_index section has been updated to include symbols for
612 inlined functions. GDB will ignore older .gdb_index sections by
613 default, which could cause symbol files to be loaded more slowly
614 until their .gdb_index sections can be recreated. The new command
615 "set use-deprecated-index-sections on" will cause GDB to use any older
616 .gdb_index sections it finds. This will restore performance, but the
617 ability to set breakpoints on inlined functions will be lost in symbol
618 files with older .gdb_index sections.
620 The .gdb_index section has also been updated to record more information
621 about each symbol. This speeds up the "info variables", "info functions"
622 and "info types" commands when used with programs having the .gdb_index
623 section, as well as speeding up debugging with shared libraries using
624 the .gdb_index section.
626 * Ada support for GDB/MI Variable Objects has been added.
628 * GDB can now support 'breakpoint always-inserted mode' in 'record'
633 ** New command -info-os is the MI equivalent of "info os".
635 ** Output logs ("set logging" and related) now include MI output.
639 ** "set use-deprecated-index-sections on|off"
640 "show use-deprecated-index-sections on|off"
641 Controls the use of deprecated .gdb_index sections.
643 ** "catch load" and "catch unload" can be used to stop when a shared
644 library is loaded or unloaded, respectively.
646 ** "enable count" can be used to auto-disable a breakpoint after
649 ** "info vtbl" can be used to show the virtual method tables for
650 C++ and Java objects.
652 ** "explore" and its sub commands "explore value" and "explore type"
653 can be used to recursively explore values and types of
654 expressions. These commands are available only if GDB is
655 configured with '--with-python'.
657 ** "info auto-load" shows status of all kinds of auto-loaded files,
658 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
659 sequences of commands files, "info auto-load python-scripts"
660 shows status of auto-loading Python script files,
661 "info auto-load local-gdbinit" shows status of loading init file
662 (.gdbinit) from current directory and "info auto-load libthread-db" shows
663 status of inferior specific thread debugging shared library loading.
665 ** "info auto-load-scripts", "set auto-load-scripts on|off"
666 and "show auto-load-scripts" commands have been deprecated, use their
667 "info auto-load python-scripts", "set auto-load python-scripts on|off"
668 and "show auto-load python-scripts" counterparts instead.
670 ** "dprintf location,format,args..." creates a dynamic printf, which
671 is basically a breakpoint that does a printf and immediately
672 resumes your program's execution, so it is like a printf that you
673 can insert dynamically at runtime instead of at compiletime.
675 ** "set print symbol"
677 Controls whether GDB attempts to display the symbol, if any,
678 corresponding to addresses it prints. This defaults to "on", but
679 you can set it to "off" to restore GDB's previous behavior.
681 * Deprecated commands
683 ** For the Renesas Super-H architecture, the "regs" command has been
684 deprecated, and "info all-registers" should be used instead.
688 Renesas RL78 rl78-*-elf
689 HP OpenVMS ia64 ia64-hp-openvms*
691 * GDBserver supports evaluation of breakpoint conditions. When
692 support is advertised by GDBserver, GDB may be told to send the
693 breakpoint conditions in bytecode form to GDBserver. GDBserver
694 will only report the breakpoint trigger to GDB when its condition
700 show mips compression
701 Select the compressed ISA encoding used in functions that have no symbol
702 information available. The encoding can be set to either of:
705 and is updated automatically from ELF file flags if available.
707 set breakpoint condition-evaluation
708 show breakpoint condition-evaluation
709 Control whether breakpoint conditions are evaluated by GDB ("host") or by
710 GDBserver ("target"). Default option "auto" chooses the most efficient
712 This option can improve debugger efficiency depending on the speed of the
716 Disable auto-loading globally.
719 Show auto-loading setting of all kinds of auto-loaded files.
721 set auto-load gdb-scripts on|off
722 show auto-load gdb-scripts
723 Control auto-loading of GDB canned sequences of commands files.
725 set auto-load python-scripts on|off
726 show auto-load python-scripts
727 Control auto-loading of Python script files.
729 set auto-load local-gdbinit on|off
730 show auto-load local-gdbinit
731 Control loading of init file (.gdbinit) from current directory.
733 set auto-load libthread-db on|off
734 show auto-load libthread-db
735 Control auto-loading of inferior specific thread debugging shared library.
737 set auto-load scripts-directory <dir1>[:<dir2>...]
738 show auto-load scripts-directory
739 Set a list of directories from which to load auto-loaded scripts.
740 Automatically loaded Python scripts and GDB scripts are located in one
741 of the directories listed by this option.
742 The delimiter (':' above) may differ according to the host platform.
744 set auto-load safe-path <dir1>[:<dir2>...]
745 show auto-load safe-path
746 Set a list of directories from which it is safe to auto-load files.
747 The delimiter (':' above) may differ according to the host platform.
749 set debug auto-load on|off
751 Control display of debugging info for auto-loading the files above.
753 set dprintf-style gdb|call|agent
755 Control the way in which a dynamic printf is performed; "gdb"
756 requests a GDB printf command, while "call" causes dprintf to call a
757 function in the inferior. "agent" requests that the target agent
758 (such as GDBserver) do the printing.
760 set dprintf-function <expr>
761 show dprintf-function
762 set dprintf-channel <expr>
764 Set the function and optional first argument to the call when using
765 the "call" style of dynamic printf.
767 set disconnected-dprintf on|off
768 show disconnected-dprintf
769 Control whether agent-style dynamic printfs continue to be in effect
770 after GDB disconnects.
772 * New configure options
775 Configure default value for the 'set auto-load scripts-directory'
776 setting above. It defaults to '$debugdir:$datadir/auto-load',
777 $debugdir representing global debugging info directories (available
778 via 'show debug-file-directory') and $datadir representing GDB's data
779 directory (available via 'show data-directory').
781 --with-auto-load-safe-path
782 Configure default value for the 'set auto-load safe-path' setting
783 above. It defaults to the --with-auto-load-dir setting.
785 --without-auto-load-safe-path
786 Set 'set auto-load safe-path' to '/', effectively disabling this
791 z0/z1 conditional breakpoints extension
793 The z0/z1 breakpoint insertion packets have been extended to carry
794 a list of conditional expressions over to the remote stub depending on the
795 condition evaluation mode. The use of this extension can be controlled
796 via the "set remote conditional-breakpoints-packet" command.
800 Specify the signals which the remote stub may pass to the debugged
801 program without GDB involvement.
803 * New command line options
805 --init-command=FILE, -ix Like --command, -x but execute it
806 before loading inferior.
807 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
808 execute it before loading inferior.
810 *** Changes in GDB 7.4
812 * GDB now handles ambiguous linespecs more consistently; the existing
813 FILE:LINE support has been expanded to other types of linespecs. A
814 breakpoint will now be set on all matching locations in all
815 inferiors, and locations will be added or removed according to
818 * GDB now allows you to skip uninteresting functions and files when
819 stepping with the "skip function" and "skip file" commands.
821 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
822 and "show remote hardware-watchpoint-length-limit". These allows to
823 set or show the maximum length limit (in bytes) of a remote
824 target hardware watchpoint.
826 This allows e.g. to use "unlimited" hardware watchpoints with the
827 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
828 watchpoints are slower than real hardware watchpoints but are
829 significantly faster than gdb software watchpoints.
833 ** The register_pretty_printer function in module gdb.printing now takes
834 an optional `replace' argument. If True, the new printer replaces any
837 ** The "maint set python print-stack on|off" command has been
838 deprecated and will be deleted in GDB 7.5.
839 A new command: "set python print-stack none|full|message" has
840 replaced it. Additionally, the default for "print-stack" is
841 now "message", which just prints the error message without
844 ** A prompt substitution hook (prompt_hook) is now available to the
847 ** A new Python module, gdb.prompt has been added to the GDB Python
848 modules library. This module provides functionality for
849 escape sequences in prompts (used by set/show
850 extended-prompt). These escape sequences are replaced by their
853 ** Python commands and convenience-functions located in
854 'data-directory'/python/gdb/command and
855 'data-directory'/python/gdb/function are now automatically loaded
858 ** Blocks now provide four new attributes. global_block and
859 static_block will return the global and static blocks
860 respectively. is_static and is_global are boolean attributes
861 that indicate if the block is one of those two types.
863 ** Symbols now provide the "type" attribute, the type of the symbol.
865 ** The "gdb.breakpoint" function has been deprecated in favor of
868 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
869 of a function. This class is based on the "finish" command
870 available in the CLI.
872 ** Type objects for struct and union types now allow access to
873 the fields using standard Python dictionary (mapping) methods.
874 For example, "some_type['myfield']" now works, as does
877 ** A new event "gdb.new_objfile" has been added, triggered by loading a
880 ** A new function, "deep_items" has been added to the gdb.types
881 module in the GDB Python modules library. This function returns
882 an iterator over the fields of a struct or union type. Unlike
883 the standard Python "iteritems" method, it will recursively traverse
884 any anonymous fields.
888 ** "*stopped" events can report several new "reason"s, such as
891 ** Breakpoint changes are now notified using new async records, like
892 "=breakpoint-modified".
894 ** New command -ada-task-info.
896 * libthread-db-search-path now supports two special values: $sdir and $pdir.
897 $sdir specifies the default system locations of shared libraries.
898 $pdir specifies the directory where the libpthread used by the application
901 GDB no longer looks in $sdir and $pdir after it has searched the directories
902 mentioned in libthread-db-search-path. If you want to search those
903 directories, they must be specified in libthread-db-search-path.
904 The default value of libthread-db-search-path on GNU/Linux and Solaris
905 systems is now "$sdir:$pdir".
907 $pdir is not supported by gdbserver, it is currently ignored.
908 $sdir is supported by gdbserver.
910 * New configure option --with-iconv-bin.
911 When using the internationalization support like the one in the GNU C
912 library, GDB will invoke the "iconv" program to get a list of supported
913 character sets. If this program lives in a non-standard location, one can
914 use this option to specify where to find it.
916 * When natively debugging programs on PowerPC BookE processors running
917 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
918 watchpoints, which specify a mask in addition to an address to watch.
919 The mask specifies that some bits of an address (the bits which are
920 reset in the mask) should be ignored when matching the address accessed
921 by the inferior against the watchpoint address. See the "PowerPC Embedded"
922 section in the user manual for more details.
924 * The new option --once causes GDBserver to stop listening for connections once
925 the first connection is made. The listening port used by GDBserver will
926 become available after that.
928 * New commands "info macros" and "alias" have been added.
930 * New function parameters suffix @entry specifies value of function parameter
931 at the time the function got called. Entry values are available only since
937 "!" is now an alias of the "shell" command.
938 Note that no space is needed between "!" and SHELL COMMAND.
942 watch EXPRESSION mask MASK_VALUE
943 The watch command now supports the mask argument which allows creation
944 of masked watchpoints, if the current architecture supports this feature.
946 info auto-load-scripts [REGEXP]
947 This command was formerly named "maintenance print section-scripts".
948 It is now generally useful and is no longer a maintenance-only command.
950 info macro [-all] [--] MACRO
951 The info macro command has new options `-all' and `--'. The first for
952 printing all definitions of a macro. The second for explicitly specifying
953 the end of arguments and the beginning of the macro name in case the macro
954 name starts with a hyphen.
956 collect[/s] EXPRESSIONS
957 The tracepoint collect command now takes an optional modifier "/s"
958 that directs it to dereference pointer-to-character types and
959 collect the bytes of memory up to a zero byte. The behavior is
960 similar to what you see when you use the regular print command on a
961 string. An optional integer following the "/s" sets a bound on the
962 number of bytes that will be collected.
965 The trace start command now interprets any supplied arguments as a
966 note to be recorded with the trace run, with an effect similar to
967 setting the variable trace-notes.
970 The trace stop command now interprets any arguments as a note to be
971 mentioned along with the tstatus report that the trace was stopped
972 with a command. The effect is similar to setting the variable
975 * Tracepoints can now be enabled and disabled at any time after a trace
976 experiment has been started using the standard "enable" and "disable"
977 commands. It is now possible to start a trace experiment with no enabled
978 tracepoints; GDB will display a warning, but will allow the experiment to
979 begin, assuming that tracepoints will be enabled as needed while the trace
982 * Fast tracepoints on 32-bit x86-architectures can now be placed at
983 locations with 4-byte instructions, when they were previously
984 limited to locations with instructions of 5 bytes or longer.
988 set debug dwarf2-read
989 show debug dwarf2-read
990 Turns on or off display of debugging messages related to reading
991 DWARF debug info. The default is off.
993 set debug symtab-create
994 show debug symtab-create
995 Turns on or off display of debugging messages related to symbol table
996 creation. The default is off.
1000 Set the GDB prompt, and allow escape sequences to be inserted to
1001 display miscellaneous information (see 'help set extended-prompt'
1002 for the list of sequences). This prompt (and any information
1003 accessed through the escape sequences) is updated every time the
1004 prompt is displayed.
1006 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1007 show print entry-values
1008 Set printing of frame argument values at function entry. In some cases
1009 GDB can determine the value of function argument which was passed by the
1010 function caller, even if the value was modified inside the called function.
1012 set debug entry-values
1013 show debug entry-values
1014 Control display of debugging info for determining frame argument values at
1015 function entry and virtual tail call frames.
1017 set basenames-may-differ
1018 show basenames-may-differ
1019 Set whether a source file may have multiple base names.
1020 (A "base name" is the name of a file with the directory part removed.
1021 Example: The base name of "/home/user/hello.c" is "hello.c".)
1022 If set, GDB will canonicalize file names (e.g., expand symlinks)
1023 before comparing them. Canonicalization is an expensive operation,
1024 but it allows the same file be known by more than one base name.
1025 If not set (the default), all source files are assumed to have just
1026 one base name, and gdb will do file name comparisons more efficiently.
1032 Set a user name and notes for the current and any future trace runs.
1033 This is useful for long-running and/or disconnected traces, to
1034 inform others (or yourself) as to who is running the trace, supply
1035 contact information, or otherwise explain what is going on.
1037 set trace-stop-notes
1038 show trace-stop-notes
1039 Set a note attached to the trace run, that is displayed when the
1040 trace has been stopped by a tstop command. This is useful for
1041 instance as an explanation, if you are stopping a trace run that was
1042 started by someone else.
1044 * New remote packets
1048 Dynamically enable a tracepoint in a started trace experiment.
1052 Dynamically disable a tracepoint in a started trace experiment.
1056 Set the user and notes of the trace run.
1060 Query the current status of a tracepoint.
1064 Query the minimum length of instruction at which a fast tracepoint may
1067 * Dcache size (number of lines) and line-size are now runtime-configurable
1068 via "set dcache line" and "set dcache line-size" commands.
1072 Texas Instruments TMS320C6x tic6x-*-*
1076 Renesas RL78 rl78-*-elf
1078 *** Changes in GDB 7.3.1
1080 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1082 *** Changes in GDB 7.3
1084 * GDB has a new command: "thread find [REGEXP]".
1085 It finds the thread id whose name, target id, or thread extra info
1086 matches the given regular expression.
1088 * The "catch syscall" command now works on mips*-linux* targets.
1090 * The -data-disassemble MI command now supports modes 2 and 3 for
1091 dumping the instruction opcodes.
1093 * New command line options
1095 -data-directory DIR Specify DIR as the "data-directory".
1096 This is mostly for testing purposes.
1098 * The "maint set python auto-load on|off" command has been renamed to
1099 "set auto-load-scripts on|off".
1101 * GDB has a new command: "set directories".
1102 It is like the "dir" command except that it replaces the
1103 source path list instead of augmenting it.
1105 * GDB now understands thread names.
1107 On GNU/Linux, "info threads" will display the thread name as set by
1108 prctl or pthread_setname_np.
1110 There is also a new command, "thread name", which can be used to
1111 assign a name internally for GDB to display.
1114 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1115 has been integrated into GDB.
1119 ** The function gdb.Write now accepts an optional keyword 'stream'.
1120 This keyword, when provided, will direct the output to either
1121 stdout, stderr, or GDB's logging output.
1123 ** Parameters can now be be sub-classed in Python, and in particular
1124 you may implement the get_set_doc and get_show_doc functions.
1125 This improves how Parameter set/show documentation is processed
1126 and allows for more dynamic content.
1128 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1129 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1130 have an is_valid method.
1132 ** Breakpoints can now be sub-classed in Python, and in particular
1133 you may implement a 'stop' function that is executed each time
1134 the inferior reaches that breakpoint.
1136 ** New function gdb.lookup_global_symbol looks up a global symbol.
1138 ** GDB values in Python are now callable if the value represents a
1139 function. For example, if 'some_value' represents a function that
1140 takes two integer parameters and returns a value, you can call
1141 that function like so:
1143 result = some_value (10,20)
1145 ** Module gdb.types has been added.
1146 It contains a collection of utilities for working with gdb.Types objects:
1147 get_basic_type, has_field, make_enum_dict.
1149 ** Module gdb.printing has been added.
1150 It contains utilities for writing and registering pretty-printers.
1151 New classes: PrettyPrinter, SubPrettyPrinter,
1152 RegexpCollectionPrettyPrinter.
1153 New function: register_pretty_printer.
1155 ** New commands "info pretty-printers", "enable pretty-printer" and
1156 "disable pretty-printer" have been added.
1158 ** gdb.parameter("directories") is now available.
1160 ** New function gdb.newest_frame returns the newest frame in the
1163 ** The gdb.InferiorThread class has a new "name" attribute. This
1164 holds the thread's name.
1166 ** Python Support for Inferior events.
1167 Python scripts can add observers to be notified of events
1168 occurring in the process being debugged.
1169 The following events are currently supported:
1170 - gdb.events.cont Continue event.
1171 - gdb.events.exited Inferior exited event.
1172 - gdb.events.stop Signal received, and Breakpoint hit events.
1176 ** GDB now puts template parameters in scope when debugging in an
1177 instantiation. For example, if you have:
1179 template<int X> int func (void) { return X; }
1181 then if you step into func<5>, "print X" will show "5". This
1182 feature requires proper debuginfo support from the compiler; it
1183 was added to GCC 4.5.
1185 ** The motion commands "next", "finish", "until", and "advance" now
1186 work better when exceptions are thrown. In particular, GDB will
1187 no longer lose control of the inferior; instead, the GDB will
1188 stop the inferior at the point at which the exception is caught.
1189 This functionality requires a change in the exception handling
1190 code that was introduced in GCC 4.5.
1192 * GDB now follows GCC's rules on accessing volatile objects when
1193 reading or writing target state during expression evaluation.
1194 One notable difference to prior behavior is that "print x = 0"
1195 no longer generates a read of x; the value of the assignment is
1196 now always taken directly from the value being assigned.
1198 * GDB now has some support for using labels in the program's source in
1199 linespecs. For instance, you can use "advance label" to continue
1200 execution to a label.
1202 * GDB now has support for reading and writing a new .gdb_index
1203 section. This section holds a fast index of DWARF debugging
1204 information and can be used to greatly speed up GDB startup and
1205 operation. See the documentation for `save gdb-index' for details.
1207 * The "watch" command now accepts an optional "-location" argument.
1208 When used, this causes GDB to watch the memory referred to by the
1209 expression. Such a watchpoint is never deleted due to it going out
1212 * GDB now supports thread debugging of core dumps on GNU/Linux.
1214 GDB now activates thread debugging using the libthread_db library
1215 when debugging GNU/Linux core dumps, similarly to when debugging
1216 live processes. As a result, when debugging a core dump file, GDB
1217 is now able to display pthread_t ids of threads. For example, "info
1218 threads" shows the same output as when debugging the process when it
1219 was live. In earlier releases, you'd see something like this:
1222 * 1 LWP 6780 main () at main.c:10
1224 While now you see this:
1227 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1229 It is also now possible to inspect TLS variables when debugging core
1232 When debugging a core dump generated on a machine other than the one
1233 used to run GDB, you may need to point GDB at the correct
1234 libthread_db library with the "set libthread-db-search-path"
1235 command. See the user manual for more details on this command.
1237 * When natively debugging programs on PowerPC BookE processors running
1238 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1239 which stop execution of the inferior whenever it executes an instruction
1240 at any address within the specified range. See the "PowerPC Embedded"
1241 section in the user manual for more details.
1243 * New features in the GDB remote stub, GDBserver
1245 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1246 and i686 LynxOS (version 5.x).
1248 ** GDBserver is now supported on Blackfin Linux.
1250 * New native configurations
1252 ia64 HP-UX ia64-*-hpux*
1256 Analog Devices, Inc. Blackfin Processor bfin-*
1258 * Ada task switching is now supported on sparc-elf targets when
1259 debugging a program using the Ravenscar Profile. For more information,
1260 see the "Tasking Support when using the Ravenscar Profile" section
1261 in the GDB user manual.
1263 * Guile support was removed.
1265 * New features in the GNU simulator
1267 ** The --map-info flag lists all known core mappings.
1269 ** CFI flashes may be simulated via the "cfi" device.
1271 *** Changes in GDB 7.2
1273 * Shared library support for remote targets by default
1275 When GDB is configured for a generic, non-OS specific target, like
1276 for example, --target=arm-eabi or one of the many *-*-elf targets,
1277 GDB now queries remote stubs for loaded shared libraries using the
1278 `qXfer:libraries:read' packet. Previously, shared library support
1279 was always disabled for such configurations.
1283 ** Argument Dependent Lookup (ADL)
1285 In C++ ADL lookup directs function search to the namespaces of its
1286 arguments even if the namespace has not been imported.
1296 Here the compiler will search for `foo' in the namespace of 'b'
1297 and find A::foo. GDB now supports this. This construct is commonly
1298 used in the Standard Template Library for operators.
1300 ** Improved User Defined Operator Support
1302 In addition to member operators, GDB now supports lookup of operators
1303 defined in a namespace and imported with a `using' directive, operators
1304 defined in the global scope, operators imported implicitly from an
1305 anonymous namespace, and the ADL operators mentioned in the previous
1307 GDB now also supports proper overload resolution for all the previously
1308 mentioned flavors of operators.
1310 ** static const class members
1312 Printing of static const class members that are initialized in the
1313 class definition has been fixed.
1315 * Windows Thread Information Block access.
1317 On Windows targets, GDB now supports displaying the Windows Thread
1318 Information Block (TIB) structure. This structure is visible either
1319 by using the new command `info w32 thread-information-block' or, by
1320 dereferencing the new convenience variable named `$_tlb', a
1321 thread-specific pointer to the TIB. This feature is also supported
1322 when remote debugging using GDBserver.
1324 * Static tracepoints
1326 Static tracepoints are calls in the user program into a tracing
1327 library. One such library is a port of the LTTng kernel tracer to
1328 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1329 When debugging with GDBserver, GDB now supports combining the GDB
1330 tracepoint machinery with such libraries. For example: the user can
1331 use GDB to probe a static tracepoint marker (a call from the user
1332 program into the tracing library) with the new "strace" command (see
1333 "New commands" below). This creates a "static tracepoint" in the
1334 breakpoint list, that can be manipulated with the same feature set
1335 as fast and regular tracepoints. E.g., collect registers, local and
1336 global variables, collect trace state variables, and define
1337 tracepoint conditions. In addition, the user can collect extra
1338 static tracepoint marker specific data, by collecting the new
1339 $_sdata internal variable. When analyzing the trace buffer, you can
1340 inspect $_sdata like any other variable available to GDB. For more
1341 information, see the "Tracepoints" chapter in GDB user manual. New
1342 remote packets have been defined to support static tracepoints, see
1343 the "New remote packets" section below.
1345 * Better reconstruction of tracepoints after disconnected tracing
1347 GDB will attempt to download the original source form of tracepoint
1348 definitions when starting a trace run, and then will upload these
1349 upon reconnection to the target, resulting in a more accurate
1350 reconstruction of the tracepoints that are in use on the target.
1354 You can now exercise direct control over the ways that GDB can
1355 affect your program. For instance, you can disallow the setting of
1356 breakpoints, so that the program can run continuously (assuming
1357 non-stop mode). In addition, the "observer" variable is available
1358 to switch all of the different controls; in observer mode, GDB
1359 cannot affect the target's behavior at all, which is useful for
1360 tasks like diagnosing live systems in the field.
1362 * The new convenience variable $_thread holds the number of the
1365 * New remote packets
1369 Return the address of the Windows Thread Information Block of a given thread.
1373 In response to several of the tracepoint packets, the target may now
1374 also respond with a number of intermediate `qRelocInsn' request
1375 packets before the final result packet, to have GDB handle
1376 relocating an instruction to execute at a different address. This
1377 is particularly useful for stubs that support fast tracepoints. GDB
1378 reports support for this feature in the qSupported packet.
1382 List static tracepoint markers in the target program.
1386 List static tracepoint markers at a given address in the target
1389 qXfer:statictrace:read
1391 Read the static trace data collected (by a `collect $_sdata'
1392 tracepoint action). The remote stub reports support for this packet
1393 to gdb's qSupported query.
1397 Send the current settings of GDB's permission flags.
1401 Send part of the source (textual) form of a tracepoint definition,
1402 which includes location, conditional, and action list.
1404 * The source command now accepts a -s option to force searching for the
1405 script in the source search path even if the script name specifies
1408 * New features in the GDB remote stub, GDBserver
1410 - GDBserver now support tracepoints (including fast tracepoints, and
1411 static tracepoints). The feature is currently supported by the
1412 i386-linux and amd64-linux builds. See the "Tracepoints support
1413 in gdbserver" section in the manual for more information.
1415 GDBserver JIT compiles the tracepoint's conditional agent
1416 expression bytecode into native code whenever possible for low
1417 overhead dynamic tracepoints conditionals. For such tracepoints,
1418 an expression that examines program state is evaluated when the
1419 tracepoint is reached, in order to determine whether to capture
1420 trace data. If the condition is simple and false, processing the
1421 tracepoint finishes very quickly and no data is gathered.
1423 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1424 for static tracepoints support.
1426 - GDBserver now supports x86_64 Windows 64-bit debugging.
1428 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1429 it understands register description.
1431 * The --batch flag now disables pagination and queries.
1433 * X86 general purpose registers
1435 GDB now supports reading/writing byte, word and double-word x86
1436 general purpose registers directly. This means you can use, say,
1437 $ah or $ax to refer, respectively, to the byte register AH and
1438 16-bit word register AX that are actually portions of the 32-bit
1439 register EAX or 64-bit register RAX.
1441 * The `commands' command now accepts a range of breakpoints to modify.
1442 A plain `commands' following a command that creates multiple
1443 breakpoints affects all the breakpoints set by that command. This
1444 applies to breakpoints set by `rbreak', and also applies when a
1445 single `break' command creates multiple breakpoints (e.g.,
1446 breakpoints on overloaded c++ functions).
1448 * The `rbreak' command now accepts a filename specification as part of
1449 its argument, limiting the functions selected by the regex to those
1450 in the specified file.
1452 * Support for remote debugging Windows and SymbianOS shared libraries
1453 from Unix hosts has been improved. Non Windows GDB builds now can
1454 understand target reported file names that follow MS-DOS based file
1455 system semantics, such as file names that include drive letters and
1456 use the backslash character as directory separator. This makes it
1457 possible to transparently use the "set sysroot" and "set
1458 solib-search-path" on Unix hosts to point as host copies of the
1459 target's shared libraries. See the new command "set
1460 target-file-system-kind" described below, and the "Commands to
1461 specify files" section in the user manual for more information.
1465 eval template, expressions...
1466 Convert the values of one or more expressions under the control
1467 of the string template to a command line, and call it.
1469 set target-file-system-kind unix|dos-based|auto
1470 show target-file-system-kind
1471 Set or show the assumed file system kind for target reported file
1474 save breakpoints <filename>
1475 Save all current breakpoint definitions to a file suitable for use
1476 in a later debugging session. To read the saved breakpoint
1477 definitions, use the `source' command.
1479 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1482 info static-tracepoint-markers
1483 Display information about static tracepoint markers in the target.
1485 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1486 Define a static tracepoint by probing a marker at the given
1487 function, line, address, or marker ID.
1491 Enable and disable observer mode.
1493 set may-write-registers on|off
1494 set may-write-memory on|off
1495 set may-insert-breakpoints on|off
1496 set may-insert-tracepoints on|off
1497 set may-insert-fast-tracepoints on|off
1498 set may-interrupt on|off
1499 Set individual permissions for GDB effects on the target. Note that
1500 some of these settings can have undesirable or surprising
1501 consequences, particularly when changed in the middle of a session.
1502 For instance, disabling the writing of memory can prevent
1503 breakpoints from being inserted, cause single-stepping to fail, or
1504 even crash your program, if you disable after breakpoints have been
1505 inserted. However, GDB should not crash.
1507 set record memory-query on|off
1508 show record memory-query
1509 Control whether to stop the inferior if memory changes caused
1510 by an instruction cannot be recorded.
1515 The disassemble command now supports "start,+length" form of two arguments.
1519 ** GDB now provides a new directory location, called the python directory,
1520 where Python scripts written for GDB can be installed. The location
1521 of that directory is <data-directory>/python, where <data-directory>
1522 is the GDB data directory. For more details, see section `Scripting
1523 GDB using Python' in the manual.
1525 ** The GDB Python API now has access to breakpoints, symbols, symbol
1526 tables, program spaces, inferiors, threads and frame's code blocks.
1527 Additionally, GDB Parameters can now be created from the API, and
1528 manipulated via set/show in the CLI.
1530 ** New functions gdb.target_charset, gdb.target_wide_charset,
1531 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1533 ** New exception gdb.GdbError.
1535 ** Pretty-printers are now also looked up in the current program space.
1537 ** Pretty-printers can now be individually enabled and disabled.
1539 ** GDB now looks for names of Python scripts to auto-load in a
1540 special section named `.debug_gdb_scripts', in addition to looking
1541 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1543 * Tracepoint actions were unified with breakpoint commands. In particular,
1544 there are no longer differences in "info break" output for breakpoints and
1545 tracepoints and the "commands" command can be used for both tracepoints and
1546 regular breakpoints.
1550 ARM Symbian arm*-*-symbianelf*
1552 * D language support.
1553 GDB now supports debugging programs written in the D programming
1556 * GDB now supports the extended ptrace interface for PowerPC which is
1557 available since Linux kernel version 2.6.34. This automatically enables
1558 any hardware breakpoints and additional hardware watchpoints available in
1559 the processor. The old ptrace interface exposes just one hardware
1560 watchpoint and no hardware breakpoints.
1562 * GDB is now able to use the Data Value Compare (DVC) register available on
1563 embedded PowerPC processors to implement in hardware simple watchpoint
1564 conditions of the form:
1566 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1568 This works in native GDB running on Linux kernels with the extended ptrace
1569 interface mentioned above.
1571 *** Changes in GDB 7.1
1575 ** Namespace Support
1577 GDB now supports importing of namespaces in C++. This enables the
1578 user to inspect variables from imported namespaces. Support for
1579 namepace aliasing has also been added. So, if a namespace is
1580 aliased in the current scope (e.g. namepace C=A; ) the user can
1581 print variables using the alias (e.g. (gdb) print C::x).
1585 All known bugs relating to the printing of virtual base class were
1586 fixed. It is now possible to call overloaded static methods using a
1591 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1592 and reinterpret_cast<> are now handled by the C++ expression parser.
1596 Xilinx MicroBlaze microblaze-*-*
1601 Xilinx MicroBlaze microblaze
1604 * Multi-program debugging.
1606 GDB now has support for multi-program (a.k.a. multi-executable or
1607 multi-exec) debugging. This allows for debugging multiple inferiors
1608 simultaneously each running a different program under the same GDB
1609 session. See "Debugging Multiple Inferiors and Programs" in the
1610 manual for more information. This implied some user visible changes
1611 in the multi-inferior support. For example, "info inferiors" now
1612 lists inferiors that are not running yet or that have exited
1613 already. See also "New commands" and "New options" below.
1615 * New tracing features
1617 GDB's tracepoint facility now includes several new features:
1619 ** Trace state variables
1621 GDB tracepoints now include support for trace state variables, which
1622 are variables managed by the target agent during a tracing
1623 experiment. They are useful for tracepoints that trigger each
1624 other, so for instance one tracepoint can count hits in a variable,
1625 and then a second tracepoint has a condition that is true when the
1626 count reaches a particular value. Trace state variables share the
1627 $-syntax of GDB convenience variables, and can appear in both
1628 tracepoint actions and condition expressions. Use the "tvariable"
1629 command to create, and "info tvariables" to view; see "Trace State
1630 Variables" in the manual for more detail.
1634 GDB now includes an option for defining fast tracepoints, which
1635 targets may implement more efficiently, such as by installing a jump
1636 into the target agent rather than a trap instruction. The resulting
1637 speedup can be by two orders of magnitude or more, although the
1638 tradeoff is that some program locations on some target architectures
1639 might not allow fast tracepoint installation, for instance if the
1640 instruction to be replaced is shorter than the jump. To request a
1641 fast tracepoint, use the "ftrace" command, with syntax identical to
1642 the regular trace command.
1644 ** Disconnected tracing
1646 It is now possible to detach GDB from the target while it is running
1647 a trace experiment, then reconnect later to see how the experiment
1648 is going. In addition, a new variable disconnected-tracing lets you
1649 tell the target agent whether to continue running a trace if the
1650 connection is lost unexpectedly.
1654 GDB now has the ability to save the trace buffer into a file, and
1655 then use that file as a target, similarly to you can do with
1656 corefiles. You can select trace frames, print data that was
1657 collected in them, and use tstatus to display the state of the
1658 tracing run at the moment that it was saved. To create a trace
1659 file, use "tsave <filename>", and to use it, do "target tfile
1662 ** Circular trace buffer
1664 You can ask the target agent to handle the trace buffer as a
1665 circular buffer, discarding the oldest trace frames to make room for
1666 newer ones, by setting circular-trace-buffer to on. This feature may
1667 not be available for all target agents.
1672 The disassemble command, when invoked with two arguments, now requires
1673 the arguments to be comma-separated.
1676 The info variables command now displays variable definitions. Files
1677 which only declare a variable are not shown.
1680 The source command is now capable of sourcing Python scripts.
1681 This feature is dependent on the debugger being build with Python
1684 Related to this enhancement is also the introduction of a new command
1685 "set script-extension" (see below).
1687 * New commands (for set/show, see "New options" below)
1689 record save [<FILENAME>]
1690 Save a file (in core file format) containing the process record
1691 execution log for replay debugging at a later time.
1693 record restore <FILENAME>
1694 Restore the process record execution log that was saved at an
1695 earlier time, for replay debugging.
1697 add-inferior [-copies <N>] [-exec <FILENAME>]
1700 clone-inferior [-copies <N>] [ID]
1701 Make a new inferior ready to execute the same program another
1702 inferior has loaded.
1707 maint info program-spaces
1708 List the program spaces loaded into GDB.
1710 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1711 show remote interrupt-sequence
1712 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1713 as the sequence to the remote target in order to interrupt the execution.
1714 Ctrl-C is a default. Some system prefers BREAK which is high level of
1715 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1716 Magic SysRq g. It is BREAK signal and character 'g'.
1718 set remote interrupt-on-connect [on | off]
1719 show remote interrupt-on-connect
1720 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1721 remote target when gdb connects to it. This is needed when you debug
1724 set remotebreak [on | off]
1726 Deprecated. Use "set/show remote interrupt-sequence" instead.
1728 tvariable $NAME [ = EXP ]
1729 Create or modify a trace state variable.
1732 List trace state variables and their values.
1734 delete tvariable $NAME ...
1735 Delete one or more trace state variables.
1738 Evaluate the given expressions without collecting anything into the
1739 trace buffer. (Valid in tracepoint actions only.)
1741 ftrace FN / FILE:LINE / *ADDR
1742 Define a fast tracepoint at the given function, line, or address.
1744 * New expression syntax
1746 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1747 GDB now parses 0b101010 identically with 42.
1751 set follow-exec-mode new|same
1752 show follow-exec-mode
1753 Control whether GDB reuses the same inferior across an exec call or
1754 creates a new one. This is useful to be able to restart the old
1755 executable after the inferior having done an exec call.
1757 set default-collect EXPR, ...
1758 show default-collect
1759 Define a list of expressions to be collected at each tracepoint.
1760 This is a useful way to ensure essential items are not overlooked,
1761 such as registers or a critical global variable.
1763 set disconnected-tracing
1764 show disconnected-tracing
1765 If set to 1, the target is instructed to continue tracing if it
1766 loses its connection to GDB. If 0, the target is to stop tracing
1769 set circular-trace-buffer
1770 show circular-trace-buffer
1771 If set to on, the target is instructed to use a circular trace buffer
1772 and discard the oldest trace frames instead of stopping the trace due
1773 to a full trace buffer. If set to off, the trace stops when the buffer
1774 fills up. Some targets may not support this.
1776 set script-extension off|soft|strict
1777 show script-extension
1778 If set to "off", the debugger does not perform any script language
1779 recognition, and all sourced files are assumed to be GDB scripts.
1780 If set to "soft" (the default), files are sourced according to
1781 filename extension, falling back to GDB scripts if the first
1783 If set to "strict", files are sourced according to filename extension.
1785 set ada trust-PAD-over-XVS on|off
1786 show ada trust-PAD-over-XVS
1787 If off, activate a workaround against a bug in the debugging information
1788 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1789 the GCC sources for more information about the GNAT encoding and
1790 PAD types in particular). It is always safe to set this option to
1791 off, but this introduces a slight performance penalty. The default
1794 * Python API Improvements
1796 ** GDB provides the new class gdb.LazyString. This is useful in
1797 some pretty-printing cases. The new method gdb.Value.lazy_string
1798 provides a simple way to create objects of this type.
1800 ** The fields returned by gdb.Type.fields now have an
1801 `is_base_class' attribute.
1803 ** The new method gdb.Type.range returns the range of an array type.
1805 ** The new method gdb.parse_and_eval can be used to parse and
1806 evaluate an expression.
1808 * New remote packets
1811 Define a trace state variable.
1814 Get the current value of a trace state variable.
1817 Set desired tracing behavior upon disconnection.
1820 Set the trace buffer to be linear or circular.
1823 Get data about the tracepoints currently in use.
1827 Process record now works correctly with hardware watchpoints.
1829 Multiple bug fixes have been made to the mips-irix port, making it
1830 much more reliable. In particular:
1831 - Debugging threaded applications is now possible again. Previously,
1832 GDB would hang while starting the program, or while waiting for
1833 the program to stop at a breakpoint.
1834 - Attaching to a running process no longer hangs.
1835 - An error occurring while loading a core file has been fixed.
1836 - Changing the value of the PC register now works again. This fixes
1837 problems observed when using the "jump" command, or when calling
1838 a function from GDB, or even when assigning a new value to $pc.
1839 - With the "finish" and "return" commands, the return value for functions
1840 returning a small array is now correctly printed.
1841 - It is now possible to break on shared library code which gets executed
1842 during a shared library init phase (code executed while executing
1843 their .init section). Previously, the breakpoint would have no effect.
1844 - GDB is now able to backtrace through the signal handler for
1845 non-threaded programs.
1847 PIE (Position Independent Executable) programs debugging is now supported.
1848 This includes debugging execution of PIC (Position Independent Code) shared
1849 libraries although for that, it should be possible to run such libraries as an
1852 *** Changes in GDB 7.0
1854 * GDB now has an interface for JIT compilation. Applications that
1855 dynamically generate code can create symbol files in memory and register
1856 them with GDB. For users, the feature should work transparently, and
1857 for JIT developers, the interface is documented in the GDB manual in the
1858 "JIT Compilation Interface" chapter.
1860 * Tracepoints may now be conditional. The syntax is as for
1861 breakpoints; either an "if" clause appended to the "trace" command,
1862 or the "condition" command is available. GDB sends the condition to
1863 the target for evaluation using the same bytecode format as is used
1864 for tracepoint actions.
1866 * The disassemble command now supports: an optional /r modifier, print the
1867 raw instructions in hex as well as in symbolic form, and an optional /m
1868 modifier to print mixed source+assembly.
1870 * Process record and replay
1872 In a architecture environment that supports ``process record and
1873 replay'', ``process record and replay'' target can record a log of
1874 the process execution, and replay it with both forward and reverse
1877 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1878 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1879 set execution-direction {forward|reverse}, for targets that support
1882 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1883 feature is available with a native GDB running on kernel version
1886 * GDB now has support for multi-byte and wide character sets on the
1887 target. Strings whose character type is wchar_t, char16_t, or
1888 char32_t are now correctly printed. GDB supports wide- and unicode-
1889 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1890 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1891 `printf'. This feature requires iconv to work properly; if your
1892 system does not have a working iconv, GDB can use GNU libiconv. See
1893 the installation instructions for more information.
1895 * GDB now supports automatic retrieval of shared library files from
1896 remote targets. To use this feature, specify a system root that begins
1897 with the `remote:' prefix, either via the `set sysroot' command or via
1898 the `--with-sysroot' configure-time option.
1900 * "info sharedlibrary" now takes an optional regex of libraries to show,
1901 and it now reports if a shared library has no debugging information.
1903 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1904 now complete on file names.
1906 * When completing in expressions, gdb will attempt to limit
1907 completions to allowable structure or union fields, where appropriate.
1908 For instance, consider:
1910 # struct example { int f1; double f2; };
1911 # struct example variable;
1914 If the user types TAB at the end of this command line, the available
1915 completions will be "f1" and "f2".
1917 * Inlined functions are now supported. They show up in backtraces, and
1918 the "step", "next", and "finish" commands handle them automatically.
1920 * GDB now supports the token-splicing (##) and stringification (#)
1921 operators when expanding macros. It also supports variable-arity
1924 * GDB now supports inspecting extra signal information, exported by
1925 the new $_siginfo convenience variable. The feature is currently
1926 implemented on linux ARM, i386 and amd64.
1928 * GDB can now display the VFP floating point registers and NEON vector
1929 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1930 can provide these registers (requires Linux 2.6.30 or later). Remote
1931 and simulator targets may also provide them.
1933 * New remote packets
1936 Search memory for a sequence of bytes.
1939 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1940 operation over reliable transport links. Use of this packet is
1941 controlled by the `set remote noack-packet' command.
1944 Kill the process with the specified process ID. Use this in preference
1945 to `k' when multiprocess protocol extensions are supported.
1948 Obtains additional operating system information
1952 Read or write additional signal information.
1954 * Removed remote protocol undocumented extension
1956 An undocumented extension to the remote protocol's `S' stop reply
1957 packet that permited the stub to pass a process id was removed.
1958 Remote servers should use the `T' stop reply packet instead.
1960 * GDB now supports multiple function calling conventions according to the
1961 DWARF-2 DW_AT_calling_convention function attribute.
1963 * The SH target utilizes the aforementioned change to distinguish between gcc
1964 and Renesas calling convention. It also adds the new CLI commands
1965 `set/show sh calling-convention'.
1967 * GDB can now read compressed debug sections, as produced by GNU gold
1968 with the --compress-debug-sections=zlib flag.
1970 * 64-bit core files are now supported on AIX.
1972 * Thread switching is now supported on Tru64.
1974 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1975 which will be allocated using malloc later in program execution.
1977 * The qXfer:libraries:read remote procotol packet now allows passing a
1978 list of section offsets.
1980 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1981 conditions handling signals delivered during attach or thread creation
1982 have also been fixed.
1984 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1985 From the user's standpoint, all unqualified instances of True and False
1986 are treated as the standard definitions, regardless of context.
1988 * GDB now parses C++ symbol and type names more flexibly. For
1991 template<typename T> class C { };
1994 GDB will now correctly handle all of:
1996 ptype C<char const *>
1997 ptype C<char const*>
1998 ptype C<const char *>
1999 ptype C<const char*>
2001 * New features in the GDB remote stub, gdbserver
2003 - The "--wrapper" command-line argument tells gdbserver to use a
2004 wrapper program to launch programs for debugging.
2006 - On PowerPC and S/390 targets, it is now possible to use a single
2007 gdbserver executable to debug both 32-bit and 64-bit programs.
2008 (This requires gdbserver itself to be built as a 64-bit executable.)
2010 - gdbserver uses the new noack protocol mode for TCP connections to
2011 reduce communications latency, if also supported and enabled in GDB.
2013 - Support for the sparc64-linux-gnu target is now included in
2016 - The amd64-linux build of gdbserver now supports debugging both
2017 32-bit and 64-bit programs.
2019 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2020 now support hardware watchpoints, and will use them automatically
2025 GDB now has support for scripting using Python. Whether this is
2026 available is determined at configure time.
2028 New GDB commands can now be written in Python.
2030 * Ada tasking support
2032 Ada tasks can now be inspected in GDB. The following commands have
2036 Print the list of Ada tasks.
2038 Print detailed information about task number N.
2040 Print the task number of the current task.
2042 Switch the context of debugging to task number N.
2044 * Support for user-defined prefixed commands. The "define" command can
2045 add new commands to existing prefixes, e.g. "target".
2047 * Multi-inferior, multi-process debugging.
2049 GDB now has generalized support for multi-inferior debugging. See
2050 "Debugging Multiple Inferiors" in the manual for more information.
2051 Although availability still depends on target support, the command
2052 set is more uniform now. The GNU/Linux specific multi-forks support
2053 has been migrated to this new framework. This implied some user
2054 visible changes; see "New commands" and also "Removed commands"
2057 * Target descriptions can now describe the target OS ABI. See the
2058 "Target Description Format" section in the user manual for more
2061 * Target descriptions can now describe "compatible" architectures
2062 to indicate that the target can execute applications for a different
2063 architecture in addition to those for the main target architecture.
2064 See the "Target Description Format" section in the user manual for
2067 * Multi-architecture debugging.
2069 GDB now includes general supports for debugging applications on
2070 hybrid systems that use more than one single processor architecture
2071 at the same time. Each such hybrid architecture still requires
2072 specific support to be added. The only hybrid architecture supported
2073 in this version of GDB is the Cell Broadband Engine.
2075 * GDB now supports integrated debugging of Cell/B.E. applications that
2076 use both the PPU and SPU architectures. To enable support for hybrid
2077 Cell/B.E. debugging, you need to configure GDB to support both the
2078 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2079 --enable-targets configure option.
2081 * Non-stop mode debugging.
2083 For some targets, GDB now supports an optional mode of operation in
2084 which you can examine stopped threads while other threads continue
2085 to execute freely. This is referred to as non-stop mode, with the
2086 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2087 section in the user manual for more information.
2089 To be able to support remote non-stop debugging, a remote stub needs
2090 to implement the non-stop mode remote protocol extensions, as
2091 described in the "Remote Non-Stop" section of the user manual. The
2092 GDB remote stub, gdbserver, has been adjusted to support these
2093 extensions on linux targets.
2095 * New commands (for set/show, see "New options" below)
2097 catch syscall [NAME(S) | NUMBER(S)]
2098 Catch system calls. Arguments, which should be names of system
2099 calls or their numbers, mean catch only those syscalls. Without
2100 arguments, every syscall will be caught. When the inferior issues
2101 any of the specified syscalls, GDB will stop and announce the system
2102 call, both when it is called and when its call returns. This
2103 feature is currently available with a native GDB running on the
2104 Linux Kernel, under the following architectures: x86, x86_64,
2105 PowerPC and PowerPC64.
2107 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2109 Search memory for a sequence of bytes.
2111 maint set python print-stack
2112 maint show python print-stack
2113 Show a stack trace when an error is encountered in a Python script.
2116 Invoke CODE by passing it to the Python interpreter.
2121 These allow macros to be defined, undefined, and listed
2125 Show operating system information about processes.
2128 List the inferiors currently under GDB's control.
2131 Switch focus to inferior number NUM.
2134 Detach from inferior number NUM.
2137 Kill inferior number NUM.
2141 set spu stop-on-load
2142 show spu stop-on-load
2143 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2145 set spu auto-flush-cache
2146 show spu auto-flush-cache
2147 Control whether to automatically flush the software-managed cache
2148 during Cell/B.E. debugging.
2150 set sh calling-convention
2151 show sh calling-convention
2152 Control the calling convention used when calling SH target functions.
2155 show debug timestamp
2156 Control display of timestamps with GDB debugging output.
2158 set disassemble-next-line
2159 show disassemble-next-line
2160 Control display of disassembled source lines or instructions when
2163 set remote noack-packet
2164 show remote noack-packet
2165 Set/show the use of remote protocol QStartNoAckMode packet. See above
2166 under "New remote packets."
2168 set remote query-attached-packet
2169 show remote query-attached-packet
2170 Control use of remote protocol `qAttached' (query-attached) packet.
2172 set remote read-siginfo-object
2173 show remote read-siginfo-object
2174 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2177 set remote write-siginfo-object
2178 show remote write-siginfo-object
2179 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2182 set remote reverse-continue
2183 show remote reverse-continue
2184 Control use of remote protocol 'bc' (reverse-continue) packet.
2186 set remote reverse-step
2187 show remote reverse-step
2188 Control use of remote protocol 'bs' (reverse-step) packet.
2190 set displaced-stepping
2191 show displaced-stepping
2192 Control displaced stepping mode. Displaced stepping is a way to
2193 single-step over breakpoints without removing them from the debuggee.
2194 Also known as "out-of-line single-stepping".
2197 show debug displaced
2198 Control display of debugging info for displaced stepping.
2200 maint set internal-error
2201 maint show internal-error
2202 Control what GDB does when an internal error is detected.
2204 maint set internal-warning
2205 maint show internal-warning
2206 Control what GDB does when an internal warning is detected.
2211 Use a wrapper program to launch programs for debugging.
2213 set multiple-symbols (all|ask|cancel)
2214 show multiple-symbols
2215 The value of this variable can be changed to adjust the debugger behavior
2216 when an expression or a breakpoint location contains an ambiguous symbol
2217 name (an overloaded function name, for instance).
2219 set breakpoint always-inserted
2220 show breakpoint always-inserted
2221 Keep breakpoints always inserted in the target, as opposed to inserting
2222 them when resuming the target, and removing them when the target stops.
2223 This option can improve debugger performance on slow remote targets.
2225 set arm fallback-mode (arm|thumb|auto)
2226 show arm fallback-mode
2227 set arm force-mode (arm|thumb|auto)
2229 These commands control how ARM GDB determines whether instructions
2230 are ARM or Thumb. The default for both settings is auto, which uses
2231 the current CPSR value for instructions without symbols; previous
2232 versions of GDB behaved as if "set arm fallback-mode arm".
2234 set disable-randomization
2235 show disable-randomization
2236 Standalone programs run with the virtual address space randomization enabled
2237 by default on some platforms. This option keeps the addresses stable across
2238 multiple debugging sessions.
2242 Control whether other threads are stopped or not when some thread hits
2247 Requests that asynchronous execution is enabled in the target, if available.
2248 In this case, it's possible to resume target in the background, and interact
2249 with GDB while the target is running. "show target-async" displays the
2250 current state of asynchronous execution of the target.
2252 set target-wide-charset
2253 show target-wide-charset
2254 The target-wide-charset is the name of the character set that GDB
2255 uses when printing characters whose type is wchar_t.
2257 set tcp auto-retry (on|off)
2259 set tcp connect-timeout
2260 show tcp connect-timeout
2261 These commands allow GDB to retry failed TCP connections to a remote stub
2262 with a specified timeout period; this is useful if the stub is launched
2263 in parallel with GDB but may not be ready to accept connections immediately.
2265 set libthread-db-search-path
2266 show libthread-db-search-path
2267 Control list of directories which GDB will search for appropriate
2270 set schedule-multiple (on|off)
2271 show schedule-multiple
2272 Allow GDB to resume all threads of all processes or only threads of
2273 the current process.
2277 Use more aggressive caching for accesses to the stack. This improves
2278 performance of remote debugging (particularly backtraces) without
2279 affecting correctness.
2281 set interactive-mode (on|off|auto)
2282 show interactive-mode
2283 Control whether GDB runs in interactive mode (on) or not (off).
2284 When in interactive mode, GDB waits for the user to answer all
2285 queries. Otherwise, GDB does not wait and assumes the default
2286 answer. When set to auto (the default), GDB determines which
2287 mode to use based on the stdin settings.
2292 For program forks, this is replaced by the new more generic `info
2293 inferiors' command. To list checkpoints, you can still use the
2294 `info checkpoints' command, which was an alias for the `info forks'
2298 Replaced by the new `inferior' command. To switch between
2299 checkpoints, you can still use the `restart' command, which was an
2300 alias for the `fork' command.
2303 This is removed, since some targets don't have a notion of
2304 processes. To switch between processes, you can still use the
2305 `inferior' command using GDB's own inferior number.
2308 For program forks, this is replaced by the new more generic `kill
2309 inferior' command. To delete a checkpoint, you can still use the
2310 `delete checkpoint' command, which was an alias for the `delete
2314 For program forks, this is replaced by the new more generic `detach
2315 inferior' command. To detach a checkpoint, you can still use the
2316 `detach checkpoint' command, which was an alias for the `detach
2319 * New native configurations
2321 x86/x86_64 Darwin i[34567]86-*-darwin*
2323 x86_64 MinGW x86_64-*-mingw*
2327 Lattice Mico32 lm32-*
2328 x86 DICOS i[34567]86-*-dicos*
2329 x86_64 DICOS x86_64-*-dicos*
2332 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2333 (mingw32ce) debugging.
2339 These commands were actually not implemented on any target.
2341 *** Changes in GDB 6.8
2343 * New native configurations
2345 NetBSD/hppa hppa*-*netbsd*
2346 Xtensa GNU/Linux xtensa*-*-linux*
2350 NetBSD/hppa hppa*-*-netbsd*
2351 Xtensa GNU/Lunux xtensa*-*-linux*
2353 * Change in command line behavior -- corefiles vs. process ids.
2355 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2356 attaching to process NUMBER fails, GDB no longer attempts to open a
2357 core file named NUMBER. Attaching to a program using the -c option
2358 is no longer supported. Instead, use the '-p' or '--pid' options.
2360 * GDB can now be built as a native debugger for debugging Windows x86
2361 (mingw32) Portable Executable (PE) programs.
2363 * Pending breakpoints no longer change their number when their address
2366 * GDB now supports breakpoints with multiple locations,
2367 including breakpoints on C++ constructors, inside C++ templates,
2368 and in inlined functions.
2370 * GDB's ability to debug optimized code has been improved. GDB more
2371 accurately identifies function bodies and lexical blocks that occupy
2372 more than one contiguous range of addresses.
2374 * Target descriptions can now describe registers for PowerPC.
2376 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2377 registers on PowerPC targets.
2379 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2380 targets even when the libthread_db library is not available.
2382 * The GDB remote stub, gdbserver, now supports the new file transfer
2383 commands (remote put, remote get, and remote delete).
2385 * The GDB remote stub, gdbserver, now supports run and attach in
2386 extended-remote mode.
2388 * hppa*64*-*-hpux11* target broken
2389 The debugger is unable to start a program and fails with the following
2390 error: "Error trying to get information about dynamic linker".
2391 The gdb-6.7 release is also affected.
2393 * GDB now supports the --enable-targets= configure option to allow
2394 building a single GDB executable that supports multiple remote
2395 target architectures.
2397 * GDB now supports debugging C and C++ programs which use the
2398 Decimal Floating Point extension. In addition, the PowerPC target
2399 now has a set of pseudo-registers to inspect decimal float values
2400 stored in two consecutive float registers.
2402 * The -break-insert MI command can optionally create pending
2405 * Improved support for debugging Ada
2406 Many improvements to the Ada language support have been made. These
2408 - Better support for Ada2005 interface types
2409 - Improved handling of arrays and slices in general
2410 - Better support for Taft-amendment types
2411 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2413 - Improved command completion in Ada
2416 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2421 set print frame-arguments (all|scalars|none)
2422 show print frame-arguments
2423 The value of this variable can be changed to control which argument
2424 values should be printed by the debugger when displaying a frame.
2429 Transfer files to and from a remote target, and delete remote files.
2436 Transfer files to and from a remote target, and delete remote files.
2438 * New remote packets
2445 Open, close, read, write, and delete files on the remote system.
2448 Attach to an existing process on the remote system, in extended-remote
2452 Run a new process on the remote system, in extended-remote mode.
2454 *** Changes in GDB 6.7
2456 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2457 bfd, libiberty and opcodes, as revealed by static analysis donated by
2458 Coverity, Inc. (http://scan.coverity.com).
2460 * When looking up multiply-defined global symbols, GDB will now prefer the
2461 symbol definition in the current shared library if it was built using the
2462 -Bsymbolic linker option.
2464 * When the Text User Interface (TUI) is not configured, GDB will now
2465 recognize the -tui command-line option and print a message that the TUI
2468 * The GDB remote stub, gdbserver, now has lower overhead for high
2469 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2471 * GDB for MIPS targets now autodetects whether a remote target provides
2472 32-bit or 64-bit register values.
2474 * Support for C++ member pointers has been improved.
2476 * GDB now understands XML target descriptions, which specify the
2477 target's overall architecture. GDB can read a description from
2478 a local file or over the remote serial protocol.
2480 * Vectors of single-byte data use a new integer type which is not
2481 automatically displayed as character or string data.
2483 * The /s format now works with the print command. It displays
2484 arrays of single-byte integers and pointers to single-byte integers
2487 * Target descriptions can now describe target-specific registers,
2488 for architectures which have implemented the support (currently
2489 only ARM, M68K, and MIPS).
2491 * GDB and the GDB remote stub, gdbserver, now support the XScale
2494 * The GDB remote stub, gdbserver, has been updated to support
2495 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2496 has been rewritten to use the standard GDB remote protocol.
2498 * GDB can now step into C++ functions which are called through thunks.
2500 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2502 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2503 layout. It also supports a TextSeg= and DataSeg= response when only
2504 segment base addresses (rather than offsets) are available.
2506 * The /i format now outputs any trailing branch delay slot instructions
2507 immediately following the last instruction within the count specified.
2509 * The GDB remote protocol "T" stop reply packet now supports a
2510 "library" response. Combined with the new "qXfer:libraries:read"
2511 packet, this response allows GDB to debug shared libraries on targets
2512 where the operating system manages the list of loaded libraries (e.g.
2513 Windows and SymbianOS).
2515 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2516 (DLLs) on Windows and Windows CE targets.
2518 * GDB now supports a faster verification that a .debug file matches its binary
2519 according to its build-id signature, if the signature is present.
2525 Enable or disable hardware flow control (RTS/CTS) on the serial port
2526 when debugging using remote targets.
2528 set mem inaccessible-by-default
2529 show mem inaccessible-by-default
2530 If the target supplies a memory map, for instance via the remote
2531 protocol's "qXfer:memory-map:read" packet, setting this variable
2532 prevents GDB from accessing memory outside the memory map. This
2533 is useful for targets with memory mapped registers or which react
2534 badly to accesses of unmapped address space.
2536 set breakpoint auto-hw
2537 show breakpoint auto-hw
2538 If the target supplies a memory map, for instance via the remote
2539 protocol's "qXfer:memory-map:read" packet, setting this variable
2540 lets GDB use hardware breakpoints automatically for memory regions
2541 where it can not use software breakpoints. This covers both the
2542 "break" command and internal breakpoints used for other commands
2543 including "next" and "finish".
2546 catch exception unhandled
2547 Stop the program execution when Ada exceptions are raised.
2550 Stop the program execution when an Ada assertion failed.
2554 Set an alternate system root for target files. This is a more
2555 general version of "set solib-absolute-prefix", which is now
2556 an alias to "set sysroot".
2559 Provide extended SPU facility status information. This set of
2560 commands is available only when debugging the Cell/B.E. SPU
2563 * New native configurations
2565 OpenBSD/sh sh*-*openbsd*
2568 unset tdesc filename
2570 Use the specified local file as an XML target description, and do
2571 not query the target for its built-in description.
2575 OpenBSD/sh sh*-*-openbsd*
2576 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2577 Toshiba Media Processor mep-elf
2579 * New remote packets
2582 Ignore the specified signals; pass them directly to the debugged program
2583 without stopping other threads or reporting them to GDB.
2585 qXfer:features:read:
2586 Read an XML target description from the target, which describes its
2591 Read or write contents of an spufs file on the target system. These
2592 packets are available only on the Cell/B.E. SPU architecture.
2594 qXfer:libraries:read:
2595 Report the loaded shared libraries. Combined with new "T" packet
2596 response, this packet allows GDB to debug shared libraries on
2597 targets where the operating system manages the list of loaded
2598 libraries (e.g. Windows and SymbianOS).
2602 Support for these obsolete configurations has been removed.
2610 i[34567]86-*-lynxos*
2611 i[34567]86-*-netware*
2612 i[34567]86-*-sco3.2v5*
2613 i[34567]86-*-sco3.2v4*
2615 i[34567]86-*-sysv4.2*
2618 i[34567]86-*-unixware2*
2619 i[34567]86-*-unixware*
2628 * Other removed features
2635 Various m68k-only ROM monitors.
2642 Various Renesas ROM monitors and debugging interfaces for SH and
2647 Support for a Macraigor serial interface to on-chip debugging.
2648 GDB does not directly support the newer parallel or USB
2653 A debug information format. The predecessor to DWARF 2 and
2654 DWARF 3, which are still supported.
2656 Support for the HP aCC compiler on HP-UX/PA-RISC
2658 SOM-encapsulated symbolic debugging information, automatic
2659 invocation of pxdb, and the aCC custom C++ ABI. This does not
2660 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2661 with aCC can still be debugged on an assembly level.
2663 MIPS ".pdr" sections
2665 A MIPS-specific format used to describe stack frame layout
2666 in debugging information.
2670 GDB could work with an older version of Guile to debug
2671 the interpreter and Scheme programs running in it.
2673 set mips stack-arg-size
2674 set mips saved-gpreg-size
2676 Use "set mips abi" to control parameter passing for MIPS.
2678 *** Changes in GDB 6.6
2683 Cell Broadband Engine SPU spu-elf
2685 * GDB can now be configured as a cross-debugger targeting native Windows
2686 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2687 running on a Windows system over TCP/IP to debug Windows programs.
2689 * The GDB remote stub, gdbserver, has been updated to support Windows and
2690 Cygwin debugging. Both single-threaded and multi-threaded programs are
2693 * The "set trust-readonly-sections" command works again. This command was
2694 broken in GDB 6.3, 6.4, and 6.5.
2696 * The "load" command now supports writing to flash memory, if the remote
2697 stub provides the required support.
2699 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2700 longer requires symbolic debug information (e.g. DWARF-2).
2705 unset substitute-path
2706 show substitute-path
2707 Manage a list of substitution rules that GDB uses to rewrite the name
2708 of the directories where the sources are located. This can be useful
2709 for instance when the sources were moved to a different location
2710 between compilation and debugging.
2714 Print each CLI command as it is executed. Each command is prefixed with
2715 a number of `+' symbols representing the nesting depth.
2716 The source command now has a `-v' option to enable the same feature.
2720 The ARM Demon monitor support (RDP protocol, "target rdp").
2722 Kernel Object Display, an embedded debugging feature which only worked with
2723 an obsolete version of Cisco IOS.
2725 The 'set download-write-size' and 'show download-write-size' commands.
2727 * New remote packets
2730 Tell a stub about GDB client features, and request remote target features.
2731 The first feature implemented is PacketSize, which allows the target to
2732 specify the size of packets it can handle - to minimize the number of
2733 packets required and improve performance when connected to a remote
2737 Fetch an OS auxilliary vector from the remote stub. This packet is a
2738 more efficient replacement for qPart:auxv:read.
2740 qXfer:memory-map:read:
2741 Fetch a memory map from the remote stub, including information about
2742 RAM, ROM, and flash memory devices.
2747 Erase and program a flash memory device.
2749 * Removed remote packets
2752 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2753 used it, and only gdbserver implemented it.
2755 *** Changes in GDB 6.5
2759 Renesas M32C/M16C m32c-elf
2761 Morpho Technologies ms1 ms1-elf
2765 init-if-undefined Initialize a convenience variable, but
2766 only if it doesn't already have a value.
2768 The following commands are presently only implemented for native GNU/Linux:
2770 checkpoint Save a snapshot of the program state.
2772 restart <n> Return the program state to a
2773 previously saved state.
2775 info checkpoints List currently saved checkpoints.
2777 delete-checkpoint <n> Delete a previously saved checkpoint.
2779 set|show detach-on-fork Tell gdb whether to detach from a newly
2780 forked process, or to keep debugging it.
2782 info forks List forks of the user program that
2783 are available to be debugged.
2785 fork <n> Switch to debugging one of several
2786 forks of the user program that are
2787 available to be debugged.
2789 delete-fork <n> Delete a fork from the list of forks
2790 that are available to be debugged (and
2791 kill the forked process).
2793 detach-fork <n> Delete a fork from the list of forks
2794 that are available to be debugged (and
2795 allow the process to continue).
2799 Morpho Technologies ms2 ms1-elf
2801 * Improved Windows host support
2803 GDB now builds as a cross debugger hosted on i686-mingw32, including
2804 native console support, and remote communications using either
2805 network sockets or serial ports.
2807 * Improved Modula-2 language support
2809 GDB can now print most types in the Modula-2 syntax. This includes:
2810 basic types, set types, record types, enumerated types, range types,
2811 pointer types and ARRAY types. Procedure var parameters are correctly
2812 printed and hexadecimal addresses and character constants are also
2813 written in the Modula-2 syntax. Best results can be obtained by using
2814 GNU Modula-2 together with the -gdwarf-2 command line option.
2818 The ARM rdi-share module.
2820 The Netware NLM debug server.
2822 *** Changes in GDB 6.4
2824 * New native configurations
2826 OpenBSD/arm arm*-*-openbsd*
2827 OpenBSD/mips64 mips64-*-openbsd*
2831 Morpho Technologies ms1 ms1-elf
2833 * New command line options
2835 --batch-silent As for --batch, but totally silent.
2836 --return-child-result The debugger will exist with the same value
2837 the child (debugged) program exited with.
2838 --eval-command COMMAND, -ex COMMAND
2839 Execute a single GDB CLI command. This may be
2840 specified multiple times and in conjunction
2841 with the --command (-x) option.
2843 * Deprecated commands removed
2845 The following commands, that were deprecated in 2000, have been
2849 set|show arm disassembly-flavor set|show arm disassembler
2850 othernames set arm disassembler
2851 set|show remotedebug set|show debug remote
2852 set|show archdebug set|show debug arch
2853 set|show eventdebug set|show debug event
2856 * New BSD user-level threads support
2858 It is now possible to debug programs using the user-level threads
2859 library on OpenBSD and FreeBSD. Currently supported (target)
2862 FreeBSD/amd64 x86_64-*-freebsd*
2863 FreeBSD/i386 i386-*-freebsd*
2864 OpenBSD/i386 i386-*-openbsd*
2866 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2867 are not yet supported.
2869 * New support for Matsushita MN10300 w/sim added
2870 (Work in progress). mn10300-elf.
2872 * REMOVED configurations and files
2874 VxWorks and the XDR protocol *-*-vxworks
2875 Motorola MCORE mcore-*-*
2876 National Semiconductor NS32000 ns32k-*-*
2878 * New "set print array-indexes" command
2880 After turning this setting "on", GDB prints the index of each element
2881 when displaying arrays. The default is "off" to preserve the previous
2884 * VAX floating point support
2886 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2888 * User-defined command support
2890 In addition to using $arg0..$arg9 for argument passing, it is now possible
2891 to use $argc to determine now many arguments have been passed. See the
2892 section on user-defined commands in the user manual for more information.
2894 *** Changes in GDB 6.3:
2896 * New command line option
2898 GDB now accepts -l followed by a number to set the timeout for remote
2901 * GDB works with GCC -feliminate-dwarf2-dups
2903 GDB now supports a more compact representation of DWARF-2 debug
2904 information using DW_FORM_ref_addr references. These are produced
2905 by GCC with the option -feliminate-dwarf2-dups and also by some
2906 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2907 to use -feliminate-dwarf2-dups.
2909 * Internationalization
2911 When supported by the host system, GDB will be built with
2912 internationalization (libintl). The task of marking up the sources is
2913 continued, we're looking forward to our first translation.
2917 Initial support for debugging programs compiled with the GNAT
2918 implementation of the Ada programming language has been integrated
2919 into GDB. In this release, support is limited to expression evaluation.
2921 * New native configurations
2923 GNU/Linux/m32r m32r-*-linux-gnu
2927 GDB's remote protocol now includes support for the 'p' packet. This
2928 packet is used to fetch individual registers from a remote inferior.
2930 * END-OF-LIFE registers[] compatibility module
2932 GDB's internal register infrastructure has been completely rewritten.
2933 The new infrastructure making possible the implementation of key new
2934 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2937 GDB 6.3 will be the last release to include the the registers[]
2938 compatibility module that allowed out-of-date configurations to
2939 continue to work. This change directly impacts the following
2949 powerpc bdm protocol
2951 Unless there is activity to revive these configurations, they will be
2952 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2954 * OBSOLETE configurations and files
2956 Configurations that have been declared obsolete in this release have
2957 been commented out. Unless there is activity to revive these
2958 configurations, the next release of GDB will have their sources
2959 permanently REMOVED.
2968 *** Changes in GDB 6.2.1:
2970 * MIPS `break main; run' gave an heuristic-fence-post warning
2972 When attempting to run even a simple program, a warning about
2973 heuristic-fence-post being hit would be reported. This problem has
2976 * MIPS IRIX 'long double' crashed GDB
2978 When examining a long double variable, GDB would get a segmentation
2979 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2980 IRIX long double values).
2984 A bug in the VAX stack code was causing problems with the "next"
2985 command. This problem has been fixed.
2987 *** Changes in GDB 6.2:
2989 * Fix for ``many threads''
2991 On GNU/Linux systems that use the NPTL threads library, a program
2992 rapidly creating and deleting threads would confuse GDB leading to the
2995 ptrace: No such process.
2996 thread_db_get_info: cannot get thread info: generic error
2998 This problem has been fixed.
3000 * "-async" and "-noasync" options removed.
3002 Support for the broken "-noasync" option has been removed (it caused
3005 * New ``start'' command.
3007 This command runs the program until the begining of the main procedure.
3009 * New BSD Kernel Data Access Library (libkvm) interface
3011 Using ``target kvm'' it is now possible to debug kernel core dumps and
3012 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3013 platforms. Currently supported (native-only) configurations are:
3015 FreeBSD/amd64 x86_64-*-freebsd*
3016 FreeBSD/i386 i?86-*-freebsd*
3017 NetBSD/i386 i?86-*-netbsd*
3018 NetBSD/m68k m68*-*-netbsd*
3019 NetBSD/sparc sparc-*-netbsd*
3020 OpenBSD/amd64 x86_64-*-openbsd*
3021 OpenBSD/i386 i?86-*-openbsd*
3022 OpenBSD/m68k m68*-openbsd*
3023 OpenBSD/sparc sparc-*-openbsd*
3025 * Signal trampoline code overhauled
3027 Many generic problems with GDB's signal handling code have been fixed.
3028 These include: backtraces through non-contiguous stacks; recognition
3029 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3030 call; backtrace through a signal trampoline; step into and out of
3031 signal handlers; and single-stepping in the signal trampoline.
3033 Please note that kernel bugs are a limiting factor here. These
3034 features have been shown to work on an s390 GNU/Linux system that
3035 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3037 * Cygwin support for DWARF 2 added.
3039 * New native configurations
3041 GNU/Linux/hppa hppa*-*-linux*
3042 OpenBSD/hppa hppa*-*-openbsd*
3043 OpenBSD/m68k m68*-*-openbsd*
3044 OpenBSD/m88k m88*-*-openbsd*
3045 OpenBSD/powerpc powerpc-*-openbsd*
3046 NetBSD/vax vax-*-netbsd*
3047 OpenBSD/vax vax-*-openbsd*
3049 * END-OF-LIFE frame compatibility module
3051 GDB's internal frame infrastructure has been completely rewritten.
3052 The new infrastructure making it possible to support key new features
3053 including DWARF 2 Call Frame Information. To aid in the task of
3054 migrating old configurations to this new infrastructure, a
3055 compatibility module, that allowed old configurations to continue to
3056 work, was also included.
3058 GDB 6.2 will be the last release to include this frame compatibility
3059 module. This change directly impacts the following configurations:
3069 Unless there is activity to revive these configurations, they will be
3070 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3072 * REMOVED configurations and files
3074 Sun 3, running SunOS 3 m68*-*-sunos3*
3075 Sun 3, running SunOS 4 m68*-*-sunos4*
3076 Sun 2, running SunOS 3 m68000-*-sunos3*
3077 Sun 2, running SunOS 4 m68000-*-sunos4*
3078 Motorola 680x0 running LynxOS m68*-*-lynxos*
3079 AT&T 3b1/Unix pc m68*-att-*
3080 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3081 decstation mips-dec-* mips-little-*
3082 riscos mips-*-riscos* mips-*-sysv*
3083 sonymips mips-sony-*
3084 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3086 *** Changes in GDB 6.1.1:
3088 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3090 The TUI (Text-mode User Interface) is now built as part of a default
3091 GDB configuration. It is enabled by either selecting the TUI with the
3092 command line option "-i=tui" or by running the separate "gdbtui"
3093 program. For more information on the TUI, see the manual "Debugging
3096 * Pending breakpoint support (also included in GDB 6.1)
3098 Support has been added to allow you to specify breakpoints in shared
3099 libraries that have not yet been loaded. If a breakpoint location
3100 cannot be found, and the "breakpoint pending" option is set to auto,
3101 GDB queries you if you wish to make the breakpoint pending on a future
3102 shared-library load. If and when GDB resolves the breakpoint symbol,
3103 the pending breakpoint is removed as one or more regular breakpoints
3106 Pending breakpoints are very useful for GCJ Java debugging.
3108 * Fixed ISO-C build problems
3110 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3111 non ISO-C code that stopped them being built using a more strict ISO-C
3112 compiler (e.g., IBM's C compiler).
3114 * Fixed build problem on IRIX 5
3116 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3117 wasn't able to compile compile on an IRIX 5 system.
3119 * Added execute permission to gdb/gdbserver/configure
3121 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3122 permission. This bug would cause configure to fail on a number of
3123 systems (Solaris, IRIX). Ref: server/519.
3125 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3127 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3128 has been updated to use constant array sizes.
3130 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3132 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3133 its generated DWARF Call Frame Info. This encoding was causing GDB to
3134 panic, that panic has been fixed. Ref: gdb/1628.
3136 * Fixed a problem when examining parameters in shared library code.
3138 When examining parameters in optimized shared library code generated
3139 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3140 not available''. GDB now correctly displays the variable's value.
3142 *** Changes in GDB 6.1:
3144 * Removed --with-mmalloc
3146 Support for the mmalloc memory manager has been removed, as it
3147 conflicted with the internal gdb byte cache.
3149 * Changes in AMD64 configurations
3151 The AMD64 target now includes the %cs and %ss registers. As a result
3152 the AMD64 remote protocol has changed; this affects the floating-point
3153 and SSE registers. If you rely on those registers for your debugging,
3154 you should upgrade gdbserver on the remote side.
3156 * Revised SPARC target
3158 The SPARC target has been completely revised, incorporating the
3159 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3160 support for LynxOS and SunOS 4 has been dropped. Calling functions
3161 from within GDB on operating systems with a non-executable stack
3162 (Solaris, OpenBSD) now works.
3166 GDB has a new C++ demangler which does a better job on the mangled
3167 names generated by current versions of g++. It also runs faster, so
3168 with this and other changes gdb should now start faster on large C++
3171 * DWARF 2 Location Expressions
3173 GDB support for location expressions has been extended to support function
3174 arguments and frame bases. Older versions of GDB could crash when they
3177 * C++ nested types and namespaces
3179 GDB's support for nested types and namespaces in C++ has been
3180 improved, especially if you use the DWARF 2 debugging format. (This
3181 is the default for recent versions of GCC on most platforms.)
3182 Specifically, if you have a class "Inner" defined within a class or
3183 namespace "Outer", then GDB realizes that the class's name is
3184 "Outer::Inner", not simply "Inner". This should greatly reduce the
3185 frequency of complaints about not finding RTTI symbols. In addition,
3186 if you are stopped at inside of a function defined within a namespace,
3187 GDB modifies its name lookup accordingly.
3189 * New native configurations
3191 NetBSD/amd64 x86_64-*-netbsd*
3192 OpenBSD/amd64 x86_64-*-openbsd*
3193 OpenBSD/alpha alpha*-*-openbsd*
3194 OpenBSD/sparc sparc-*-openbsd*
3195 OpenBSD/sparc64 sparc64-*-openbsd*
3197 * New debugging protocols
3199 M32R with SDI protocol m32r-*-elf*
3201 * "set prompt-escape-char" command deleted.
3203 The command "set prompt-escape-char" has been deleted. This command,
3204 and its very obscure effet on GDB's prompt, was never documented,
3205 tested, nor mentioned in the NEWS file.
3207 * OBSOLETE configurations and files
3209 Configurations that have been declared obsolete in this release have
3210 been commented out. Unless there is activity to revive these
3211 configurations, the next release of GDB will have their sources
3212 permanently REMOVED.
3214 Sun 3, running SunOS 3 m68*-*-sunos3*
3215 Sun 3, running SunOS 4 m68*-*-sunos4*
3216 Sun 2, running SunOS 3 m68000-*-sunos3*
3217 Sun 2, running SunOS 4 m68000-*-sunos4*
3218 Motorola 680x0 running LynxOS m68*-*-lynxos*
3219 AT&T 3b1/Unix pc m68*-att-*
3220 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3221 decstation mips-dec-* mips-little-*
3222 riscos mips-*-riscos* mips-*-sysv*
3223 sonymips mips-sony-*
3224 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3226 * REMOVED configurations and files
3228 SGI Irix-4.x mips-sgi-irix4 or iris4
3229 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3230 Z8000 simulator z8k-zilog-none or z8ksim
3231 Matsushita MN10200 w/simulator mn10200-*-*
3232 H8/500 simulator h8500-hitachi-hms or h8500hms
3233 HP/PA running BSD hppa*-*-bsd*
3234 HP/PA running OSF/1 hppa*-*-osf*
3235 HP/PA Pro target hppa*-*-pro*
3236 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3237 386BSD i[3456]86-*-bsd*
3238 Sequent family i[3456]86-sequent-sysv4*
3239 i[3456]86-sequent-sysv*
3240 i[3456]86-sequent-bsd*
3241 SPARC running LynxOS sparc-*-lynxos*
3242 SPARC running SunOS 4 sparc-*-sunos4*
3243 Tsqware Sparclet sparclet-*-*
3244 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3246 *** Changes in GDB 6.0:
3250 Support for debugging the Objective-C programming language has been
3251 integrated into GDB.
3253 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3255 DWARF 2's Call Frame Information makes available compiler generated
3256 information that more exactly describes the program's run-time stack.
3257 By using this information, GDB is able to provide more robust stack
3260 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3261 have been updated to use a new backtrace mechanism which includes
3262 DWARF 2 CFI support.
3266 GDB's remote protocol has been extended to include support for hosted
3267 file I/O (where the remote target uses GDB's file system). See GDB's
3268 remote protocol documentation for details.
3270 * All targets using the new architecture framework.
3272 All of GDB's targets have been updated to use the new internal
3273 architecture framework. The way is now open for future GDB releases
3274 to include cross-architecture native debugging support (i386 on amd64,
3277 * GNU/Linux's Thread Local Storage (TLS)
3279 GDB now includes support for for the GNU/Linux implementation of
3280 per-thread variables.
3282 * GNU/Linux's Native POSIX Thread Library (NPTL)
3284 GDB's thread code has been updated to work with either the new
3285 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3287 * Separate debug info.
3289 GDB, in conjunction with BINUTILS, now supports a mechanism for
3290 automatically loading debug information from a separate file. Instead
3291 of shipping full debug and non-debug versions of system libraries,
3292 system integrators can now instead ship just the stripped libraries
3293 and optional debug files.
3295 * DWARF 2 Location Expressions
3297 DWARF 2 Location Expressions allow the compiler to more completely
3298 describe the location of variables (even in optimized code) to the
3301 GDB now includes preliminary support for location expressions (support
3302 for DW_OP_piece is still missing).
3306 A number of long standing bugs that caused GDB to die while starting a
3307 Java application have been fixed. GDB's Java support is now
3308 considered "useable".
3310 * GNU/Linux support for fork, vfork, and exec.
3312 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3313 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3316 * GDB supports logging output to a file
3318 There are two new commands, "set logging" and "show logging", which can be
3319 used to capture GDB's output to a file.
3321 * The meaning of "detach" has changed for gdbserver
3323 The "detach" command will now resume the application, as documented. To
3324 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3327 * d10v, m68hc11 `regs' command deprecated
3329 The `info registers' command has been updated so that it displays the
3330 registers using a format identical to the old `regs' command.
3334 A new command, "maint set profile on/off", has been added. This command can
3335 be used to enable or disable profiling while running GDB, to profile a
3336 session or a set of commands. In addition there is a new configure switch,
3337 "--enable-profiling", which will cause GDB to be compiled with profiling
3338 data, for more informative profiling results.
3340 * Default MI syntax changed to "mi2".
3342 The default MI (machine interface) syntax, enabled by the command line
3343 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3344 "mi1", can be enabled by specifying the option "-i=mi1".
3346 Support for the original "mi0" syntax (included in GDB 5.0) has been
3349 Fix for gdb/192: removed extraneous space when displaying frame level.
3350 Fix for gdb/672: update changelist is now output in mi list format.
3351 Fix for gdb/702: a -var-assign that updates the value now shows up
3352 in a subsequent -var-update.
3354 * New native configurations.
3356 FreeBSD/amd64 x86_64-*-freebsd*
3358 * Multi-arched targets.
3360 HP/PA HPUX11 hppa*-*-hpux*
3361 Renesas M32R/D w/simulator m32r-*-elf*
3363 * OBSOLETE configurations and files
3365 Configurations that have been declared obsolete in this release have
3366 been commented out. Unless there is activity to revive these
3367 configurations, the next release of GDB will have their sources
3368 permanently REMOVED.
3370 Z8000 simulator z8k-zilog-none or z8ksim
3371 Matsushita MN10200 w/simulator mn10200-*-*
3372 H8/500 simulator h8500-hitachi-hms or h8500hms
3373 HP/PA running BSD hppa*-*-bsd*
3374 HP/PA running OSF/1 hppa*-*-osf*
3375 HP/PA Pro target hppa*-*-pro*
3376 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3377 Sequent family i[3456]86-sequent-sysv4*
3378 i[3456]86-sequent-sysv*
3379 i[3456]86-sequent-bsd*
3380 Tsqware Sparclet sparclet-*-*
3381 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3383 * REMOVED configurations and files
3386 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3387 IBM AIX PS/2 i[3456]86-*-aix
3388 i386 running Mach 3.0 i[3456]86-*-mach3*
3389 i386 running Mach i[3456]86-*-mach*
3390 i386 running OSF/1 i[3456]86-*osf1mk*
3391 HP/Apollo 68k Family m68*-apollo*-sysv*,
3393 m68*-hp-bsd*, m68*-hp-hpux*
3394 Argonaut Risc Chip (ARC) arc-*-*
3395 Mitsubishi D30V d30v-*-*
3396 Fujitsu FR30 fr30-*-elf*
3397 OS/9000 i[34]86-*-os9k
3398 I960 with MON960 i960-*-coff
3400 * MIPS $fp behavior changed
3402 The convenience variable $fp, for the MIPS, now consistently returns
3403 the address of the current frame's base. Previously, depending on the
3404 context, $fp could refer to either $sp or the current frame's base
3405 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3406 The GNU Source-Level Debugger''.
3408 *** Changes in GDB 5.3:
3410 * GNU/Linux shared library multi-threaded performance improved.
3412 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3413 `/proc', in preference to `ptrace' for memory reads. This may result
3414 in an improvement in the start-up time of multi-threaded, shared
3415 library applications when run under GDB. One GDB user writes: ``loads
3416 shared libs like mad''.
3418 * ``gdbserver'' now supports multi-threaded applications on some targets
3420 Support for debugging multi-threaded applications which use
3421 the GNU/Linux LinuxThreads package has been added for
3422 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3423 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3425 * GDB now supports C/C++ preprocessor macros.
3427 GDB now expands preprocessor macro invocations in C/C++ expressions,
3428 and provides various commands for showing macro definitions and how
3431 The new command `macro expand EXPRESSION' expands any macro
3432 invocations in expression, and shows the result.
3434 The new command `show macro MACRO-NAME' shows the definition of the
3435 macro named MACRO-NAME, and where it was defined.
3437 Most compilers don't include information about macros in the debugging
3438 information by default. In GCC 3.1, for example, you need to compile
3439 your program with the options `-gdwarf-2 -g3'. If the macro
3440 information is present in the executable, GDB will read it.
3442 * Multi-arched targets.
3444 DEC Alpha (partial) alpha*-*-*
3445 DEC VAX (partial) vax-*-*
3447 National Semiconductor NS32000 (partial) ns32k-*-*
3448 Motorola 68000 (partial) m68k-*-*
3449 Motorola MCORE mcore-*-*
3453 Fujitsu FRV architecture added by Red Hat frv*-*-*
3456 * New native configurations
3458 Alpha NetBSD alpha*-*-netbsd*
3459 SH NetBSD sh*-*-netbsdelf*
3460 MIPS NetBSD mips*-*-netbsd*
3461 UltraSPARC NetBSD sparc64-*-netbsd*
3463 * OBSOLETE configurations and files
3465 Configurations that have been declared obsolete in this release have
3466 been commented out. Unless there is activity to revive these
3467 configurations, the next release of GDB will have their sources
3468 permanently REMOVED.
3470 Mitsubishi D30V d30v-*-*
3471 OS/9000 i[34]86-*-os9k
3472 IBM AIX PS/2 i[3456]86-*-aix
3473 Fujitsu FR30 fr30-*-elf*
3474 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3475 Argonaut Risc Chip (ARC) arc-*-*
3476 i386 running Mach 3.0 i[3456]86-*-mach3*
3477 i386 running Mach i[3456]86-*-mach*
3478 i386 running OSF/1 i[3456]86-*osf1mk*
3479 HP/Apollo 68k Family m68*-apollo*-sysv*,
3481 m68*-hp-bsd*, m68*-hp-hpux*
3482 I960 with MON960 i960-*-coff
3484 * OBSOLETE languages
3486 CHILL, a Pascal like language used by telecommunications companies.
3488 * REMOVED configurations and files
3490 AMD 29k family via UDI a29k-amd-udi, udi29k
3491 A29K VxWorks a29k-*-vxworks
3492 AMD 29000 embedded, using EBMON a29k-none-none
3493 AMD 29000 embedded with COFF a29k-none-coff
3494 AMD 29000 embedded with a.out a29k-none-aout
3496 testsuite/gdb.hp/gdb.threads-hp/ directory
3498 * New command "set max-user-call-depth <nnn>"
3500 This command allows the user to limit the call depth of user-defined
3501 commands. The default is 1024.
3503 * Changes in FreeBSD/i386 native debugging.
3505 Support for the "generate-core-file" has been added.
3507 * New commands "dump", "append", and "restore".
3509 These commands allow data to be copied from target memory
3510 to a bfd-format or binary file (dump and append), and back
3511 from a file into memory (restore).
3513 * Improved "next/step" support on multi-processor Alpha Tru64.
3515 The previous single-step mechanism could cause unpredictable problems,
3516 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3517 of a software single-step mechanism prevents this.
3519 *** Changes in GDB 5.2.1:
3527 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3528 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3529 Fix, by Joel Brobecker imported from mainline.
3531 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3532 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3533 Fix, by Fred Fish, imported from mainline.
3535 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3536 Surprisingly enough, it works now.
3537 By Michal Ludvig, imported from mainline.
3539 i386 hardware watchpoint support:
3540 avoid misses on second run for some targets.
3541 By Pierre Muller, imported from mainline.
3543 *** Changes in GDB 5.2:
3545 * New command "set trust-readonly-sections on[off]".
3547 This command is a hint that tells gdb that read-only sections
3548 really are read-only (ie. that their contents will not change).
3549 In this mode, gdb will go to the object file rather than the
3550 target to read memory from read-only sections (such as ".text").
3551 This can be a significant performance improvement on some
3552 (notably embedded) targets.
3554 * New command "generate-core-file" (or "gcore").
3556 This new gdb command allows the user to drop a core file of the child
3557 process state at any time. So far it's been implemented only for
3558 GNU/Linux and Solaris, but should be relatively easily ported to other
3559 hosts. Argument is core file name (defaults to core.<pid>).
3561 * New command line option
3563 GDB now accepts --pid or -p followed by a process id.
3565 * Change in command line behavior -- corefiles vs. process ids.
3567 There is a subtle behavior in the way in which GDB handles
3568 command line arguments. The first non-flag argument is always
3569 a program to debug, but the second non-flag argument may either
3570 be a corefile or a process id. Previously, GDB would attempt to
3571 open the second argument as a corefile, and if that failed, would
3572 issue a superfluous error message and then attempt to attach it as
3573 a process. Now, if the second argument begins with a non-digit,
3574 it will be treated as a corefile. If it begins with a digit,
3575 GDB will attempt to attach it as a process, and if no such process
3576 is found, will then attempt to open it as a corefile.
3578 * Changes in ARM configurations.
3580 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3581 configuration is fully multi-arch.
3583 * New native configurations
3585 ARM NetBSD arm*-*-netbsd*
3586 x86 OpenBSD i[3456]86-*-openbsd*
3587 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3588 Sparc64 running FreeBSD sparc64-*-freebsd*
3592 Sanyo XStormy16 xstormy16-elf
3594 * OBSOLETE configurations and files
3596 Configurations that have been declared obsolete in this release have
3597 been commented out. Unless there is activity to revive these
3598 configurations, the next release of GDB will have their sources
3599 permanently REMOVED.
3601 AMD 29k family via UDI a29k-amd-udi, udi29k
3602 A29K VxWorks a29k-*-vxworks
3603 AMD 29000 embedded, using EBMON a29k-none-none
3604 AMD 29000 embedded with COFF a29k-none-coff
3605 AMD 29000 embedded with a.out a29k-none-aout
3607 testsuite/gdb.hp/gdb.threads-hp/ directory
3609 * REMOVED configurations and files
3611 TI TMS320C80 tic80-*-*
3613 PowerPC Solaris powerpcle-*-solaris*
3614 PowerPC Windows NT powerpcle-*-cygwin32
3615 PowerPC Netware powerpc-*-netware*
3616 Harris/CXUX m88k m88*-harris-cxux*
3617 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3618 ns32k-utek-sysv* ns32k-utek-*
3619 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3620 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3621 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3622 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3623 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3625 * Changes to command line processing
3627 The new `--args' feature can be used to specify command-line arguments
3628 for the inferior from gdb's command line.
3630 * Changes to key bindings
3632 There is a new `operate-and-get-next' function bound to `C-o'.
3634 *** Changes in GDB 5.1.1
3636 Fix compile problem on DJGPP.
3638 Fix a problem with floating-point registers on the i386 being
3641 Fix to stop GDB crashing on .debug_str debug info.
3643 Numerous documentation fixes.
3645 Numerous testsuite fixes.
3647 *** Changes in GDB 5.1:
3649 * New native configurations
3651 Alpha FreeBSD alpha*-*-freebsd*
3652 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3653 MIPS GNU/Linux mips*-*-linux*
3654 MIPS SGI Irix 6.x mips*-sgi-irix6*
3655 ia64 AIX ia64-*-aix*
3656 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3660 Motorola 68HC11 and 68HC12 m68hc11-elf
3662 UltraSparc running GNU/Linux sparc64-*-linux*
3664 * OBSOLETE configurations and files
3666 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3667 Harris/CXUX m88k m88*-harris-cxux*
3668 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3669 ns32k-utek-sysv* ns32k-utek-*
3670 TI TMS320C80 tic80-*-*
3672 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3673 PowerPC Solaris powerpcle-*-solaris*
3674 PowerPC Windows NT powerpcle-*-cygwin32
3675 PowerPC Netware powerpc-*-netware*
3676 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3677 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3678 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3679 Apple Macintosh (MPW) host N/A
3681 stuff.c (Program to stuff files into a specially prepared space in kdb)
3682 kdb-start.c (Main loop for the standalone kernel debugger)
3684 Configurations that have been declared obsolete in this release have
3685 been commented out. Unless there is activity to revive these
3686 configurations, the next release of GDB will have their sources
3687 permanently REMOVED.
3689 * REMOVED configurations and files
3691 Altos 3068 m68*-altos-*
3692 Convex c1-*-*, c2-*-*
3694 ARM RISCix arm-*-* (as host)
3698 * GDB has been converted to ISO C.
3700 GDB's source code has been converted to ISO C. In particular, the
3701 sources are fully protoized, and rely on standard headers being
3706 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3708 * The MI enabled by default.
3710 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3711 revised and enabled by default. Packages which use GDB as a debugging
3712 engine behind a UI or another front end are encouraged to switch to
3713 using the GDB/MI interface, instead of the old annotations interface
3714 which is now deprecated.
3716 * Support for debugging Pascal programs.
3718 GDB now includes support for debugging Pascal programs. The following
3719 main features are supported:
3721 - Pascal-specific data types such as sets;
3723 - automatic recognition of Pascal sources based on file-name
3726 - Pascal-style display of data types, variables, and functions;
3728 - a Pascal expression parser.
3730 However, some important features are not yet supported.
3732 - Pascal string operations are not supported at all;
3734 - there are some problems with boolean types;
3736 - Pascal type hexadecimal constants are not supported
3737 because they conflict with the internal variables format;
3739 - support for Pascal objects and classes is not full yet;
3741 - unlike Pascal, GDB is case-sensitive for symbol names.
3743 * Changes in completion.
3745 Commands such as `shell', `run' and `set args', which pass arguments
3746 to inferior programs, now complete on file names, similar to what
3747 users expect at the shell prompt.
3749 Commands which accept locations, such as `disassemble', `print',
3750 `breakpoint', `until', etc. now complete on filenames as well as
3751 program symbols. Thus, if you type "break foob TAB", and the source
3752 files linked into the programs include `foobar.c', that file name will
3753 be one of the candidates for completion. However, file names are not
3754 considered for completion after you typed a colon that delimits a file
3755 name from a name of a function in that file, as in "break foo.c:bar".
3757 `set demangle-style' completes on available demangling styles.
3759 * New platform-independent commands:
3761 It is now possible to define a post-hook for a command as well as a
3762 hook that runs before the command. For more details, see the
3763 documentation of `hookpost' in the GDB manual.
3765 * Changes in GNU/Linux native debugging.
3767 Support for debugging multi-threaded programs has been completely
3768 revised for all platforms except m68k and sparc. You can now debug as
3769 many threads as your system allows you to have.
3771 Attach/detach is supported for multi-threaded programs.
3773 Support for SSE registers was added for x86. This doesn't work for
3774 multi-threaded programs though.
3776 * Changes in MIPS configurations.
3778 Multi-arch support is enabled for all MIPS configurations.
3780 GDB can now be built as native debugger on SGI Irix 6.x systems for
3781 debugging n32 executables. (Debugging 64-bit executables is not yet
3784 * Unified support for hardware watchpoints in all x86 configurations.
3786 Most (if not all) native x86 configurations support hardware-assisted
3787 breakpoints and watchpoints in a unified manner. This support
3788 implements debug register sharing between watchpoints, which allows to
3789 put a virtually infinite number of watchpoints on the same address,
3790 and also supports watching regions up to 16 bytes with several debug
3793 The new maintenance command `maintenance show-debug-regs' toggles
3794 debugging print-outs in functions that insert, remove, and test
3795 watchpoints and hardware breakpoints.
3797 * Changes in the DJGPP native configuration.
3799 New command ``info dos sysinfo'' displays assorted information about
3800 the CPU, OS, memory, and DPMI server.
3802 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3803 display information about segment descriptors stored in GDT, LDT, and
3806 New commands ``info dos pde'' and ``info dos pte'' display entries
3807 from Page Directory and Page Tables (for now works with CWSDPMI only).
3808 New command ``info dos address-pte'' displays the Page Table entry for
3809 a given linear address.
3811 GDB can now pass command lines longer than 126 characters to the
3812 program being debugged (requires an update to the libdbg.a library
3813 which is part of the DJGPP development kit).
3815 DWARF2 debug info is now supported.
3817 It is now possible to `step' and `next' through calls to `longjmp'.
3819 * Changes in documentation.
3821 All GDB documentation was converted to GFDL, the GNU Free
3822 Documentation License.
3824 Tracepoints-related commands are now fully documented in the GDB
3827 TUI, the Text-mode User Interface, is now documented in the manual.
3829 Tracepoints-related commands are now fully documented in the GDB
3832 The "GDB Internals" manual now has an index. It also includes
3833 documentation of `ui_out' functions, GDB coding standards, x86
3834 hardware watchpoints, and memory region attributes.
3836 * GDB's version number moved to ``version.in''
3838 The Makefile variable VERSION has been replaced by the file
3839 ``version.in''. People creating GDB distributions should update the
3840 contents of this file.
3844 GUD support is now a standard part of the EMACS distribution.
3846 *** Changes in GDB 5.0:
3848 * Improved support for debugging FP programs on x86 targets
3850 Unified and much-improved support for debugging floating-point
3851 programs on all x86 targets. In particular, ``info float'' now
3852 displays the FP registers in the same format on all x86 targets, with
3853 greater level of detail.
3855 * Improvements and bugfixes in hardware-assisted watchpoints
3857 It is now possible to watch array elements, struct members, and
3858 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3859 on x86 targets no longer erroneously trigger when the address is
3862 * Improvements in the native DJGPP version of GDB
3864 The distribution now includes all the scripts and auxiliary files
3865 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3866 machines ``out of the box''.
3868 The DJGPP version can now debug programs that use signals. It is
3869 possible to catch signals that happened in the debuggee, deliver
3870 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3871 would kill the program being debugged.) Programs that hook hardware
3872 interrupts (keyboard, timer, etc.) can also be debugged.
3874 It is now possible to debug DJGPP programs that redirect their
3875 standard handles or switch them to raw (as opposed to cooked) mode, or
3876 even close them. The command ``run < foo > bar'' works as expected,
3877 and ``info terminal'' reports useful information about the debuggee's
3878 terminal, including raw/cooked mode, redirection, etc.
3880 The DJGPP version now uses termios functions for console I/O, which
3881 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3884 DOS-style file names with drive letters are now fully supported by
3887 It is now possible to debug DJGPP programs that switch their working
3888 directory. It is also possible to rerun the debuggee any number of
3889 times without restarting GDB; thus, you can use the same setup,
3890 breakpoints, etc. for many debugging sessions.
3892 * New native configurations
3894 ARM GNU/Linux arm*-*-linux*
3895 PowerPC GNU/Linux powerpc-*-linux*
3899 Motorola MCore mcore-*-*
3900 x86 VxWorks i[3456]86-*-vxworks*
3901 PowerPC VxWorks powerpc-*-vxworks*
3902 TI TMS320C80 tic80-*-*
3904 * OBSOLETE configurations
3906 Altos 3068 m68*-altos-*
3907 Convex c1-*-*, c2-*-*
3909 ARM RISCix arm-*-* (as host)
3912 Configurations that have been declared obsolete will be commented out,
3913 but the code will be left in place. If there is no activity to revive
3914 these configurations before the next release of GDB, the sources will
3915 be permanently REMOVED.
3917 * Gould support removed
3919 Support for the Gould PowerNode and NP1 has been removed.
3921 * New features for SVR4
3923 On SVR4 native platforms (such as Solaris), if you attach to a process
3924 without first loading a symbol file, GDB will now attempt to locate and
3925 load symbols from the running process's executable file.
3927 * Many C++ enhancements
3929 C++ support has been greatly improved. Overload resolution now works properly
3930 in almost all cases. RTTI support is on the way.
3932 * Remote targets can connect to a sub-program
3934 A popen(3) style serial-device has been added. This device starts a
3935 sub-process (such as a stand-alone simulator) and then communicates
3936 with that. The sub-program to run is specified using the syntax
3937 ``|<program> <args>'' vis:
3939 (gdb) set remotedebug 1
3940 (gdb) target extended-remote |mn10300-elf-sim program-args
3942 * MIPS 64 remote protocol
3944 A long standing bug in the mips64 remote protocol where by GDB
3945 expected certain 32 bit registers (ex SR) to be transfered as 32
3946 instead of 64 bits has been fixed.
3948 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3949 added to provide backward compatibility with older versions of GDB.
3951 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3953 The command ``set remotebinarydownload'' command has been replaced by
3954 ``set remote X-packet''. Other commands in ``set remote'' family
3955 include ``set remote P-packet''.
3957 * Breakpoint commands accept ranges.
3959 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3960 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3961 ``tracepoint passcount'' also accepts a range of tracepoints.
3963 * ``apropos'' command added.
3965 The ``apropos'' command searches through command names and
3966 documentation strings, printing out matches, making it much easier to
3967 try to find a command that does what you are looking for.
3971 A new machine oriented interface (MI) has been added to GDB. This
3972 interface is designed for debug environments running GDB as a separate
3973 process. This is part of the long term libGDB project. See the
3974 "GDB/MI" chapter of the GDB manual for further information. It can be
3975 enabled by configuring with:
3977 .../configure --enable-gdbmi
3979 *** Changes in GDB-4.18:
3981 * New native configurations
3983 HP-UX 10.20 hppa*-*-hpux10.20
3984 HP-UX 11.x hppa*-*-hpux11.0*
3985 M68K GNU/Linux m68*-*-linux*
3989 Fujitsu FR30 fr30-*-elf*
3990 Intel StrongARM strongarm-*-*
3991 Mitsubishi D30V d30v-*-*
3993 * OBSOLETE configurations
3995 Gould PowerNode, NP1 np1-*-*, pn-*-*
3997 Configurations that have been declared obsolete will be commented out,
3998 but the code will be left in place. If there is no activity to revive
3999 these configurations before the next release of GDB, the sources will
4000 be permanently REMOVED.
4004 As a compatibility experiment, GDB's source files buildsym.h and
4005 buildsym.c have been converted to pure standard C, no longer
4006 containing any K&R compatibility code. We believe that all systems in
4007 use today either come with a standard C compiler, or have a GCC port
4008 available. If this is not true, please report the affected
4009 configuration to bug-gdb@gnu.org immediately. See the README file for
4010 information about getting a standard C compiler if you don't have one
4015 GDB now uses readline 2.2.
4017 * set extension-language
4019 You can now control the mapping between filename extensions and source
4020 languages by using the `set extension-language' command. For instance,
4021 you can ask GDB to treat .c files as C++ by saying
4022 set extension-language .c c++
4023 The command `info extensions' lists all of the recognized extensions
4024 and their associated languages.
4026 * Setting processor type for PowerPC and RS/6000
4028 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4029 you can use the `set processor' command to specify what variant of the
4030 PowerPC family you are debugging. The command
4034 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4035 following PowerPC and RS6000 variants:
4037 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4038 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4040 403GC IBM PowerPC 403GC
4041 505 Motorola PowerPC 505
4042 860 Motorola PowerPC 860 or 850
4043 601 Motorola PowerPC 601
4044 602 Motorola PowerPC 602
4045 603 Motorola/IBM PowerPC 603 or 603e
4046 604 Motorola PowerPC 604 or 604e
4047 750 Motorola/IBM PowerPC 750 or 750
4049 At the moment, this command just tells GDB what to name the
4050 special-purpose processor registers. Since almost all the affected
4051 registers are inaccessible to user-level programs, this command is
4052 only useful for remote debugging in its present form.
4056 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4057 more extensive support for HP-UX. Added features include shared
4058 library support, kernel threads and hardware watchpoints for 11.00,
4059 support for HP's ANSI C and C++ compilers, and a compatibility mode
4060 for xdb and dbx commands.
4064 HP's donation includes the new concept of catchpoints, which is a
4065 generalization of the old catch command. On HP-UX, it is now possible
4066 to catch exec, fork, and vfork, as well as library loading.
4068 This means that the existing catch command has changed; its first
4069 argument now specifies the type of catch to be set up. See the
4070 output of "help catch" for a list of catchpoint types.
4072 * Debugging across forks
4074 On HP-UX, you can choose which process to debug when a fork() happens
4079 HP has donated a curses-based terminal user interface (TUI). To get
4080 it, build with --enable-tui. Although this can be enabled for any
4081 configuration, at present it only works for native HP debugging.
4083 * GDB remote protocol additions
4085 A new protocol packet 'X' that writes binary data is now available.
4086 Default behavior is to try 'X', then drop back to 'M' if the stub
4087 fails to respond. The settable variable `remotebinarydownload'
4088 allows explicit control over the use of 'X'.
4090 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4091 full 64-bit address. The command
4093 set remoteaddresssize 32
4095 can be used to revert to the old behaviour. For existing remote stubs
4096 the change should not be noticed, as the additional address information
4099 In order to assist in debugging stubs, you may use the maintenance
4100 command `packet' to send any text string to the stub. For instance,
4102 maint packet heythere
4104 sends the packet "$heythere#<checksum>". Note that it is very easy to
4105 disrupt a debugging session by sending the wrong packet at the wrong
4108 The compare-sections command allows you to compare section data on the
4109 target to what is in the executable file without uploading or
4110 downloading, by comparing CRC checksums.
4112 * Tracing can collect general expressions
4114 You may now collect general expressions at tracepoints. This requires
4115 further additions to the target-side stub; see tracepoint.c and
4116 doc/agentexpr.texi for further details.
4118 * mask-address variable for Mips
4120 For Mips targets, you may control the zeroing of the upper 32 bits of
4121 a 64-bit address by entering `set mask-address on'. This is mainly
4122 of interest to users of embedded R4xxx and R5xxx processors.
4124 * Higher serial baud rates
4126 GDB's serial code now allows you to specify baud rates 57600, 115200,
4127 230400, and 460800 baud. (Note that your host system may not be able
4128 to achieve all of these rates.)
4132 The i960 configuration now includes an initial implementation of a
4133 builtin simulator, contributed by Jim Wilson.
4136 *** Changes in GDB-4.17:
4138 * New native configurations
4140 Alpha GNU/Linux alpha*-*-linux*
4141 Unixware 2.x i[3456]86-unixware2*
4142 Irix 6.x mips*-sgi-irix6*
4143 PowerPC GNU/Linux powerpc-*-linux*
4144 PowerPC Solaris powerpcle-*-solaris*
4145 Sparc GNU/Linux sparc-*-linux*
4146 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4150 Argonaut Risc Chip (ARC) arc-*-*
4151 Hitachi H8/300S h8300*-*-*
4152 Matsushita MN10200 w/simulator mn10200-*-*
4153 Matsushita MN10300 w/simulator mn10300-*-*
4154 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4155 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4156 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4157 Mitsubishi D10V w/simulator d10v-*-*
4158 Mitsubishi M32R/D w/simulator m32r-*-elf*
4159 Tsqware Sparclet sparclet-*-*
4160 NEC V850 w/simulator v850-*-*
4162 * New debugging protocols
4164 ARM with RDI protocol arm*-*-*
4165 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4166 DDB and LSI variants of PMON protocol mips*-*-*
4167 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4168 PowerPC with SDS protocol powerpc{,le}-*-eabi
4169 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4173 All configurations can now understand and use the DWARF 2 debugging
4174 format. The choice is automatic, if the symbol file contains DWARF 2
4179 GDB now includes basic Java language support. This support is
4180 only useful with Java compilers that produce native machine code.
4182 * solib-absolute-prefix and solib-search-path
4184 For SunOS and SVR4 shared libraries, you may now set the prefix for
4185 loading absolute shared library symbol files, and the search path for
4186 locating non-absolute shared library symbol files.
4188 * Live range splitting
4190 GDB can now effectively debug code for which GCC has performed live
4191 range splitting as part of its optimization. See gdb/doc/LRS for
4192 more details on the expected format of the stabs information.
4196 GDB's support for the GNU Hurd, including thread debugging, has been
4197 updated to work with current versions of the Hurd.
4201 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4202 instruction set. ARM GDB automatically detects when Thumb
4203 instructions are in use, and adjusts disassembly and backtracing
4208 GDB's MIPS target configurations now handle the MIP16 16-bit
4213 GDB now includes support for overlays; if an executable has been
4214 linked such that multiple sections are based at the same address, GDB
4215 will decide which section to use for symbolic info. You can choose to
4216 control the decision manually, using overlay commands, or implement
4217 additional target-side support and use "overlay load-target" to bring
4218 in the overlay mapping. Do "help overlay" for more detail.
4222 The command "info symbol <address>" displays information about
4223 the symbol at the specified address.
4227 The standard remote protocol now includes an extension that allows
4228 asynchronous collection and display of trace data. This requires
4229 extensive support in the target-side debugging stub. Tracing mode
4230 includes a new interaction mode in GDB and new commands: see the
4231 file tracepoint.c for more details.
4235 Configurations for embedded MIPS now include a simulator contributed
4236 by Cygnus Solutions. The simulator supports the instruction sets
4237 of most MIPS variants.
4241 Sparc configurations may now include the ERC32 simulator contributed
4242 by the European Space Agency. The simulator is not built into
4243 Sparc targets by default; configure with --enable-sim to include it.
4247 For target configurations that may include multiple variants of a
4248 basic architecture (such as MIPS and SH), you may now set the
4249 architecture explicitly. "set arch" sets, "info arch" lists
4250 the possible architectures.
4252 *** Changes in GDB-4.16:
4254 * New native configurations
4256 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4257 M68K NetBSD m68k-*-netbsd*
4258 PowerPC AIX 4.x powerpc-*-aix*
4259 PowerPC MacOS powerpc-*-macos*
4260 PowerPC Windows NT powerpcle-*-cygwin32
4261 RS/6000 AIX 4.x rs6000-*-aix4*
4265 ARM with RDP protocol arm-*-*
4266 I960 with MON960 i960-*-coff
4267 MIPS VxWorks mips*-*-vxworks*
4268 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4269 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4271 Matra Sparclet sparclet-*-*
4275 The powerpc-eabi configuration now includes the PSIM simulator,
4276 contributed by Andrew Cagney, with assistance from Mike Meissner.
4277 PSIM is a very elaborate model of the PowerPC, including not only
4278 basic instruction set execution, but also details of execution unit
4279 performance and I/O hardware. See sim/ppc/README for more details.
4283 GDB now works with Solaris 2.5.
4285 * Windows 95/NT native
4287 GDB will now work as a native debugger on Windows 95 and Windows NT.
4288 To build it from source, you must use the "gnu-win32" environment,
4289 which uses a DLL to emulate enough of Unix to run the GNU tools.
4290 Further information, binaries, and sources are available at
4291 ftp.cygnus.com, under pub/gnu-win32.
4293 * dont-repeat command
4295 If a user-defined command includes the command `dont-repeat', then the
4296 command will not be repeated if the user just types return. This is
4297 useful if the command is time-consuming to run, so that accidental
4298 extra keystrokes don't run the same command many times.
4300 * Send break instead of ^C
4302 The standard remote protocol now includes an option to send a break
4303 rather than a ^C to the target in order to interrupt it. By default,
4304 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4306 * Remote protocol timeout
4308 The standard remote protocol includes a new variable `remotetimeout'
4309 that allows you to set the number of seconds before GDB gives up trying
4310 to read from the target. The default value is 2.
4312 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4314 By default GDB will automatically keep track of objects as they are
4315 loaded and unloaded by the dynamic linker. By using the command `set
4316 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4317 when shared library events occur, thus allowing you to set breakpoints
4318 in shared libraries which are explicitly loaded by the inferior.
4320 Note this feature does not work on hpux8. On hpux9 you must link
4321 /usr/lib/end.o into your program. This feature should work
4322 automatically on hpux10.
4324 * Irix 5.x hardware watchpoint support
4326 Irix 5 configurations now support the use of hardware watchpoints.
4328 * Mips protocol "SYN garbage limit"
4330 When debugging a Mips target using the `target mips' protocol, you
4331 may set the number of characters that GDB will ignore by setting
4332 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4333 every character. The default value is 1050.
4335 * Recording and replaying remote debug sessions
4337 If you set `remotelogfile' to the name of a file, gdb will write to it
4338 a recording of a remote debug session. This recording may then be
4339 replayed back to gdb using "gdbreplay". See gdbserver/README for
4340 details. This is useful when you have a problem with GDB while doing
4341 remote debugging; you can make a recording of the session and send it
4342 to someone else, who can then recreate the problem.
4344 * Speedups for remote debugging
4346 GDB includes speedups for downloading and stepping MIPS systems using
4347 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4348 and more efficient S-record downloading.
4350 * Memory use reductions and statistics collection
4352 GDB now uses less memory and reports statistics about memory usage.
4353 Try the `maint print statistics' command, for example.
4355 *** Changes in GDB-4.15:
4357 * Psymtabs for XCOFF
4359 The symbol reader for AIX GDB now uses partial symbol tables. This
4360 can greatly improve startup time, especially for large executables.
4362 * Remote targets use caching
4364 Remote targets now use a data cache to speed up communication with the
4365 remote side. The data cache could lead to incorrect results because
4366 it doesn't know about volatile variables, thus making it impossible to
4367 debug targets which use memory mapped I/O devices. `set remotecache
4368 off' turns the the data cache off.
4370 * Remote targets may have threads
4372 The standard remote protocol now includes support for multiple threads
4373 in the target system, using new protocol commands 'H' and 'T'. See
4374 gdb/remote.c for details.
4378 If GDB is configured with `--enable-netrom', then it will include
4379 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4380 acts as though it is a bank of ROM on the target board, but you can
4381 write into it over the network. GDB's support consists only of
4382 support for fast loading into the emulated ROM; to debug, you must use
4383 another protocol, such as standard remote protocol. The usual
4384 sequence is something like
4386 target nrom <netrom-hostname>
4388 target remote <netrom-hostname>:1235
4392 GDB now includes support for the Apple Macintosh, as a host only. It
4393 may be run as either an MPW tool or as a standalone application, and
4394 it can debug through the serial port. All the usual GDB commands are
4395 available, but to the target command, you must supply "serial" as the
4396 device type instead of "/dev/ttyXX". See mpw-README in the main
4397 directory for more information on how to build. The MPW configuration
4398 scripts */mpw-config.in support only a few targets, and only the
4399 mips-idt-ecoff target has been tested.
4403 GDB configuration now uses autoconf. This is not user-visible,
4404 but does simplify configuration and building.
4408 GDB now supports hpux10.
4410 *** Changes in GDB-4.14:
4412 * New native configurations
4414 x86 FreeBSD i[345]86-*-freebsd
4415 x86 NetBSD i[345]86-*-netbsd
4416 NS32k NetBSD ns32k-*-netbsd
4417 Sparc NetBSD sparc-*-netbsd
4421 A29K VxWorks a29k-*-vxworks
4422 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4423 CPU32 EST-300 emulator m68*-*-est*
4424 PowerPC ELF powerpc-*-elf
4427 * Alpha OSF/1 support for procfs
4429 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4430 possible to attach to running processes. As the mounting of the /proc
4431 filesystem is optional on the Alpha, GDB automatically determines
4432 the availability of /proc during startup. This can lead to problems
4433 if /proc is unmounted after GDB has been started.
4435 * Arguments to user-defined commands
4437 User commands may accept up to 10 arguments separated by whitespace.
4438 Arguments are accessed within the user command via $arg0..$arg9. A
4441 print $arg0 + $arg1 + $arg2
4443 To execute the command use:
4446 Defines the command "adder" which prints the sum of its three arguments.
4447 Note the arguments are text substitutions, so they may reference variables,
4448 use complex expressions, or even perform inferior function calls.
4450 * New `if' and `while' commands
4452 This makes it possible to write more sophisticated user-defined
4453 commands. Both commands take a single argument, which is the
4454 expression to evaluate, and must be followed by the commands to
4455 execute, one per line, if the expression is nonzero, the list being
4456 terminated by the word `end'. The `if' command list may include an
4457 `else' word, which causes the following commands to be executed only
4458 if the expression is zero.
4460 * Fortran source language mode
4462 GDB now includes partial support for Fortran 77. It will recognize
4463 Fortran programs and can evaluate a subset of Fortran expressions, but
4464 variables and functions may not be handled correctly. GDB will work
4465 with G77, but does not yet know much about symbols emitted by other
4468 * Better HPUX support
4470 Most debugging facilities now work on dynamic executables for HPPAs
4471 running hpux9 or later. You can attach to running dynamically linked
4472 processes, but by default the dynamic libraries will be read-only, so
4473 for instance you won't be able to put breakpoints in them. To change
4474 that behavior do the following before running the program:
4480 This will cause the libraries to be mapped private and read-write.
4481 To revert to the normal behavior, do this:
4487 You cannot set breakpoints or examine data in the library until after
4488 the library is loaded if the function/data symbols do not have
4491 GDB can now also read debug symbols produced by the HP C compiler on
4492 HPPAs (sorry, no C++, Fortran or 68k support).
4494 * Target byte order now dynamically selectable
4496 You can choose which byte order to use with a target system, via the
4497 commands "set endian big" and "set endian little", and you can see the
4498 current setting by using "show endian". You can also give the command
4499 "set endian auto", in which case GDB will use the byte order
4500 associated with the executable. Currently, only embedded MIPS
4501 configurations support dynamic selection of target byte order.
4503 * New DOS host serial code
4505 This version uses DPMI interrupts to handle buffered I/O, so you
4506 no longer need to run asynctsr when debugging boards connected to
4509 *** Changes in GDB-4.13:
4511 * New "complete" command
4513 This lists all the possible completions for the rest of the line, if it
4514 were to be given as a command itself. This is intended for use by emacs.
4516 * Trailing space optional in prompt
4518 "set prompt" no longer adds a space for you after the prompt you set. This
4519 allows you to set a prompt which ends in a space or one that does not.
4521 * Breakpoint hit counts
4523 "info break" now displays a count of the number of times the breakpoint
4524 has been hit. This is especially useful in conjunction with "ignore"; you
4525 can ignore a large number of breakpoint hits, look at the breakpoint info
4526 to see how many times the breakpoint was hit, then run again, ignoring one
4527 less than that number, and this will get you quickly to the last hit of
4530 * Ability to stop printing at NULL character
4532 "set print null-stop" will cause GDB to stop printing the characters of
4533 an array when the first NULL is encountered. This is useful when large
4534 arrays actually contain only short strings.
4536 * Shared library breakpoints
4538 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4539 breakpoints in shared libraries before the executable is run.
4541 * Hardware watchpoints
4543 There is a new hardware breakpoint for the watch command for sparclite
4544 targets. See gdb/sparclite/hw_breakpoint.note.
4546 Hardware watchpoints are also now supported under GNU/Linux.
4550 Annotations have been added. These are for use with graphical interfaces,
4551 and are still experimental. Currently only gdba.el uses these.
4553 * Improved Irix 5 support
4555 GDB now works properly with Irix 5.2.
4557 * Improved HPPA support
4559 GDB now works properly with the latest GCC and GAS.
4561 * New native configurations
4563 Sequent PTX4 i[34]86-sequent-ptx4
4564 HPPA running OSF/1 hppa*-*-osf*
4565 Atari TT running SVR4 m68*-*-sysv4*
4566 RS/6000 LynxOS rs6000-*-lynxos*
4570 OS/9000 i[34]86-*-os9k
4571 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4574 * Hitachi SH7000 and E7000-PC ICE support
4576 There is now support for communicating with the Hitachi E7000-PC ICE.
4577 This is available automatically when GDB is configured for the SH.
4581 As usual, a variety of small fixes and improvements, both generic
4582 and configuration-specific. See the ChangeLog for more detail.
4584 *** Changes in GDB-4.12:
4586 * Irix 5 is now supported
4590 GDB-4.12 on the HPPA has a number of changes which make it unable
4591 to debug the output from the currently released versions of GCC and
4592 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4593 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4594 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4597 *** Changes in GDB-4.11:
4599 * User visible changes:
4603 The "set remotedebug" option is now consistent between the mips remote
4604 target, remote targets using the gdb-specific protocol, UDI (AMD's
4605 debug protocol for the 29k) and the 88k bug monitor. It is now an
4606 integer specifying a debug level (normally 0 or 1, but 2 means more
4607 debugging info for the mips target).
4609 * DEC Alpha native support
4611 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4612 debug info, but GDB works fairly well with the DEC compiler and should
4613 work with a future GCC release. See the README file for a few
4614 Alpha-specific notes.
4616 * Preliminary thread implementation
4618 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4620 * LynxOS native and target support for 386
4622 This release has been hosted on LynxOS 2.2, and also can be configured
4623 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4626 * Improvements in C++ mangling/demangling.
4628 This release has much better g++ debugging, specifically in name
4629 mangling/demangling, virtual function calls, print virtual table,
4630 call methods, ...etc.
4632 *** Changes in GDB-4.10:
4634 * User visible changes:
4636 Remote debugging using the GDB-specific (`target remote') protocol now
4637 supports the `load' command. This is only useful if you have some
4638 other way of getting the stub to the target system, and you can put it
4639 somewhere in memory where it won't get clobbered by the download.
4641 Filename completion now works.
4643 When run under emacs mode, the "info line" command now causes the
4644 arrow to point to the line specified. Also, "info line" prints
4645 addresses in symbolic form (as well as hex).
4647 All vxworks based targets now support a user settable option, called
4648 vxworks-timeout. This option represents the number of seconds gdb
4649 should wait for responses to rpc's. You might want to use this if
4650 your vxworks target is, perhaps, a slow software simulator or happens
4651 to be on the far side of a thin network line.
4655 This release contains support for using a DEC alpha as a GDB host for
4656 cross debugging. Native alpha debugging is not supported yet.
4659 *** Changes in GDB-4.9:
4663 This is the first GDB release which is accompanied by a matching testsuite.
4664 The testsuite requires installation of dejagnu, which should be available
4665 via ftp from most sites that carry GNU software.
4669 'Cfront' style demangling has had its name changed to 'ARM' style, to
4670 emphasize that it was written from the specifications in the C++ Annotated
4671 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4672 disclaimers, it still generated too much confusion with users attempting to
4673 use gdb with AT&T cfront.
4677 GDB now uses a standard remote interface to a simulator library.
4678 So far, the library contains simulators for the Zilog Z8001/2, the
4679 Hitachi H8/300, H8/500 and Super-H.
4681 * New targets supported
4683 H8/300 simulator h8300-hitachi-hms or h8300hms
4684 H8/500 simulator h8500-hitachi-hms or h8500hms
4685 SH simulator sh-hitachi-hms or sh
4686 Z8000 simulator z8k-zilog-none or z8ksim
4687 IDT MIPS board over serial line mips-idt-ecoff
4689 Cross-debugging to GO32 targets is supported. It requires a custom
4690 version of the i386-stub.c module which is integrated with the
4691 GO32 memory extender.
4693 * New remote protocols
4695 MIPS remote debugging protocol.
4697 * New source languages supported
4699 This version includes preliminary support for Chill, a Pascal like language
4700 used by telecommunications companies. Chill support is also being integrated
4701 into the GNU compiler, but we don't know when it will be publically available.
4704 *** Changes in GDB-4.8:
4706 * HP Precision Architecture supported
4708 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4709 version of this support was available as a set of patches from the
4710 University of Utah. GDB does not support debugging of programs
4711 compiled with the HP compiler, because HP will not document their file
4712 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4713 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4715 Many problems in the preliminary version have been fixed.
4717 * Faster and better demangling
4719 We have improved template demangling and fixed numerous bugs in the GNU style
4720 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4721 character types (wchar_t) are now supported. Demangling of each symbol is now
4722 only done once, and is cached when the symbol table for a file is read in.
4723 This results in a small increase in memory usage for C programs, a moderate
4724 increase in memory usage for C++ programs, and a fantastic speedup in
4727 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4728 from the specifications in the Annotated Reference Manual, which AT&T's
4729 compiler does not actually implement.
4731 * G++ multiple inheritance compiler problem
4733 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4734 inheritance lattices was reworked to properly discover ambiguities. We
4735 recently found an example which causes this new algorithm to fail in a
4736 very subtle way, producing bad debug information for those classes.
4737 The file 'gcc.patch' (in this directory) can be applied to gcc to
4738 circumvent the problem. A future GCC release will contain a complete
4741 The previous G++ debug info problem (mentioned below for the gdb-4.7
4742 release) is fixed in gcc version 2.3.2.
4744 * Improved configure script
4746 The `configure' script will now attempt to guess your system type if
4747 you don't supply a host system type. The old scheme of supplying a
4748 host system triplet is preferable over using this. All the magic is
4749 done in the new `config.guess' script. Examine it for details.
4751 We have also brought our configure script much more in line with the FSF's
4752 version. It now supports the --with-xxx options. In particular,
4753 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4754 The resulting GDB will not be able to read arbitrary object file formats --
4755 only the format ``expected'' to be used on the configured target system.
4756 We hope to make this the default in a future release.
4758 * Documentation improvements
4760 There's new internal documentation on how to modify GDB, and how to
4761 produce clean changes to the code. We implore people to read it
4762 before submitting changes.
4764 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4765 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4766 `info' files are also provided. To build `info' files from scratch,
4767 you will need the latest `makeinfo' release, which will be available in
4768 a future texinfo-X.Y release.
4770 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4771 We're not sure exactly which versions have this problem, but it has
4772 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4773 or better. If that isn't possible, there is a patch in
4774 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4775 around this problem.
4779 GDB now supports array constants that can be used in expressions typed in by
4780 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4781 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4784 The new directory `gdb/sparclite' contains a program that demonstrates
4785 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4787 * New native hosts supported
4789 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4790 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4792 * New targets supported
4794 AMD 29k family via UDI a29k-amd-udi or udi29k
4796 * New file formats supported
4798 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4799 HPUX core files, and SCO 3.2v2 core files.
4803 Attaching to processes now works again; thanks for the many bug reports.
4805 We have also stomped on a bunch of core dumps caused by
4806 printf_filtered("%s") problems.
4808 We eliminated a copyright problem on the rpc and ptrace header files
4809 for VxWorks, which was discovered at the last minute during the 4.7
4810 release. You should now be able to build a VxWorks GDB.
4812 You can now interrupt gdb while an attached process is running. This
4813 will cause the attached process to stop, and give control back to GDB.
4815 We fixed problems caused by using too many file descriptors
4816 for reading symbols from object files and libraries. This was
4817 especially a problem for programs that used many (~100) shared
4820 The `step' command now only enters a subroutine if there is line number
4821 information for the subroutine. Otherwise it acts like the `next'
4822 command. Previously, `step' would enter subroutines if there was
4823 any debugging information about the routine. This avoids problems
4824 when using `cc -g1' on MIPS machines.
4826 * Internal improvements
4828 GDB's internal interfaces have been improved to make it easier to support
4829 debugging of multiple languages in the future.
4831 GDB now uses a common structure for symbol information internally.
4832 Minimal symbols (derived from linkage symbols in object files), partial
4833 symbols (from a quick scan of debug information), and full symbols
4834 contain a common subset of information, making it easier to write
4835 shared code that handles any of them.
4837 * New command line options
4839 We now accept --silent as an alias for --quiet.
4843 The memory-mapped-malloc library is now licensed under the GNU Library
4844 General Public License.
4846 *** Changes in GDB-4.7:
4848 * Host/native/target split
4850 GDB has had some major internal surgery to untangle the support for
4851 hosts and remote targets. Now, when you configure GDB for a remote
4852 target, it will no longer load in all of the support for debugging
4853 local programs on the host. When fully completed and tested, this will
4854 ensure that arbitrary host/target combinations are possible.
4856 The primary conceptual shift is to separate the non-portable code in
4857 GDB into three categories. Host specific code is required any time GDB
4858 is compiled on that host, regardless of the target. Target specific
4859 code relates to the peculiarities of the target, but can be compiled on
4860 any host. Native specific code is everything else: it can only be
4861 built when the host and target are the same system. Child process
4862 handling and core file support are two common `native' examples.
4864 GDB's use of /proc for controlling Unix child processes is now cleaner.
4865 It has been split out into a single module under the `target_ops' vector,
4866 plus two native-dependent functions for each system that uses /proc.
4868 * New hosts supported
4870 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4871 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4872 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4874 * New targets supported
4876 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4877 68030 and CPU32 m68030-*-*, m68332-*-*
4879 * New native hosts supported
4881 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4882 (386bsd is not well tested yet)
4883 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4885 * New file formats supported
4887 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4888 supports reading of `a.out.adobe' object files, which are an a.out
4889 format extended with minimal information about multiple sections.
4893 `show copying' is the same as the old `info copying'.
4894 `show warranty' is the same as `info warrantee'.
4895 These were renamed for consistency. The old commands continue to work.
4897 `info handle' is a new alias for `info signals'.
4899 You can now define pre-command hooks, which attach arbitrary command
4900 scripts to any command. The commands in the hook will be executed
4901 prior to the user's command. You can also create a hook which will be
4902 executed whenever the program stops. See gdb.texinfo.
4906 We now deal with Cfront style name mangling, and can even extract type
4907 info from mangled symbols. GDB can automatically figure out which
4908 symbol mangling style your C++ compiler uses.
4910 Calling of methods and virtual functions has been improved as well.
4914 The crash that occured when debugging Sun Ansi-C compiled binaries is
4915 fixed. This was due to mishandling of the extra N_SO stabs output
4918 We also finally got Ultrix 4.2 running in house, and fixed core file
4919 support, with help from a dozen people on the net.
4921 John M. Farrell discovered that the reason that single-stepping was so
4922 slow on all of the Mips based platforms (primarily SGI and DEC) was
4923 that we were trying to demangle and lookup a symbol used for internal
4924 purposes on every instruction that was being stepped through. Changing
4925 the name of that symbol so that it couldn't be mistaken for a C++
4926 mangled symbol sped things up a great deal.
4928 Rich Pixley sped up symbol lookups in general by getting much smarter
4929 about when C++ symbol mangling is necessary. This should make symbol
4930 completion (TAB on the command line) much faster. It's not as fast as
4931 we'd like, but it's significantly faster than gdb-4.6.
4935 A new user controllable variable 'call_scratch_address' can
4936 specify the location of a scratch area to be used when GDB
4937 calls a function in the target. This is necessary because the
4938 usual method of putting the scratch area on the stack does not work
4939 in systems that have separate instruction and data spaces.
4941 We integrated changes to support the 29k UDI (Universal Debugger
4942 Interface), but discovered at the last minute that we didn't have all
4943 of the appropriate copyright paperwork. We are working with AMD to
4944 resolve this, and hope to have it available soon.
4948 We have sped up the remote serial line protocol, especially for targets
4949 with lots of registers. It now supports a new `expedited status' ('T')
4950 message which can be used in place of the existing 'S' status message.
4951 This allows the remote stub to send only the registers that GDB
4952 needs to make a quick decision about single-stepping or conditional
4953 breakpoints, eliminating the need to fetch the entire register set for
4954 each instruction being stepped through.
4956 The GDB remote serial protocol now implements a write-through cache for
4957 registers, only re-reading the registers if the target has run.
4959 There is also a new remote serial stub for SPARC processors. You can
4960 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4961 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4962 processor with a serial port.
4966 Configure.in files have become much easier to read and modify. A new
4967 `table driven' format makes it more obvious what configurations are
4968 supported, and what files each one uses.
4972 There is a new opcodes library which will eventually contain all of the
4973 disassembly routines and opcode tables. At present, it only contains
4974 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4975 disassembler (binutils/objdump) to share these routines.
4977 The libiberty library is now copylefted under the GNU Library General
4978 Public License. This allows more liberal use, and was done so libg++
4979 can use it. This makes no difference to GDB, since the Library License
4980 grants all the rights from the General Public License.
4984 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4985 reference to the stabs symbol info used by the debugger. It is (as far
4986 as we know) the only published document on this fascinating topic. We
4987 encourage you to read it, compare it to the stabs information on your
4988 system, and send improvements on the document in general (to
4989 bug-gdb@prep.ai.mit.edu).
4991 And, of course, many bugs have been fixed.
4994 *** Changes in GDB-4.6:
4996 * Better support for C++ function names
4998 GDB now accepts as input the "demangled form" of C++ overloaded function
4999 names and member function names, and can do command completion on such names
5000 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5001 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5002 Make use of command completion, it is your friend.
5004 GDB also now accepts a variety of C++ mangled symbol formats. They are
5005 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5006 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5007 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5008 for the list of formats.
5010 * G++ symbol mangling problem
5012 Recent versions of gcc have a bug in how they emit debugging information for
5013 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5014 directory) can be applied to gcc to fix the problem. Alternatively, if you
5015 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5016 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5017 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5020 * New 'maintenance' command
5022 All of the commands related to hacking GDB internals have been moved out of
5023 the main command set, and now live behind the 'maintenance' command. This
5024 can also be abbreviated as 'mt'. The following changes were made:
5026 dump-me -> maintenance dump-me
5027 info all-breakpoints -> maintenance info breakpoints
5028 printmsyms -> maintenance print msyms
5029 printobjfiles -> maintenance print objfiles
5030 printpsyms -> maintenance print psymbols
5031 printsyms -> maintenance print symbols
5033 The following commands are new:
5035 maintenance demangle Call internal GDB demangler routine to
5036 demangle a C++ link name and prints the result.
5037 maintenance print type Print a type chain for a given symbol
5039 * Change to .gdbinit file processing
5041 We now read the $HOME/.gdbinit file before processing the argv arguments
5042 (e.g. reading symbol files or core files). This allows global parameters to
5043 be set, which will apply during the symbol reading. The ./.gdbinit is still
5044 read after argv processing.
5046 * New hosts supported
5048 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5050 GNU/Linux support i386-unknown-linux or linux
5052 We are also including code to support the HP/PA running BSD and HPUX. This
5053 is almost guaranteed not to work, as we didn't have time to test or build it
5054 for this release. We are including it so that the more adventurous (or
5055 masochistic) of you can play with it. We also had major problems with the
5056 fact that the compiler that we got from HP doesn't support the -g option.
5059 * New targets supported
5061 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5063 * More smarts about finding #include files
5065 GDB now remembers the compilation directory for all include files, and for
5066 all files from which C is generated (like yacc and lex sources). This
5067 greatly improves GDB's ability to find yacc/lex sources, and include files,
5068 especially if you are debugging your program from a directory different from
5069 the one that contains your sources.
5071 We also fixed a bug which caused difficulty with listing and setting
5072 breakpoints in include files which contain C code. (In the past, you had to
5073 try twice in order to list an include file that you hadn't looked at before.)
5075 * Interesting infernals change
5077 GDB now deals with arbitrary numbers of sections, where the symbols for each
5078 section must be relocated relative to that section's landing place in the
5079 target's address space. This work was needed to support ELF with embedded
5080 stabs used by Solaris-2.0.
5082 * Bug fixes (of course!)
5084 There have been loads of fixes for the following things:
5085 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5086 i960, stabs, DOS(GO32), procfs, etc...
5088 See the ChangeLog for details.
5090 *** Changes in GDB-4.5:
5092 * New machines supported (host and target)
5094 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5096 SGI Irix-4.x mips-sgi-irix4 or iris4
5098 * New malloc package
5100 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5101 Mmalloc is capable of handling mutiple heaps of memory. It is also
5102 capable of saving a heap to a file, and then mapping it back in later.
5103 This can be used to greatly speedup the startup of GDB by using a
5104 pre-parsed symbol table which lives in a mmalloc managed heap. For
5105 more details, please read mmalloc/mmalloc.texi.
5109 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5110 'help info proc' for details.
5112 * MIPS ecoff symbol table format
5114 The code that reads MIPS symbol table format is now supported on all hosts.
5115 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5118 * File name changes for MS-DOS
5120 Many files in the config directories have been renamed to make it easier to
5121 support GDB on MS-DOSe systems (which have very restrictive file name
5122 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5123 environment) is close to working but has some remaining problems. Note
5124 that debugging of DOS programs is not supported, due to limitations
5125 in the ``operating system'', but it can be used to host cross-debugging.
5127 * Cross byte order fixes
5129 Many fixes have been made to support cross debugging of Sparc and MIPS
5130 targets from hosts whose byte order differs.
5132 * New -mapped and -readnow options
5134 If memory-mapped files are available on your system through the 'mmap'
5135 system call, you can use the -mapped option on the `file' or
5136 `symbol-file' commands to cause GDB to write the symbols from your
5137 program into a reusable file. If the program you are debugging is
5138 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5139 Future GDB debugging sessions will notice the presence of this file,
5140 and will quickly map in symbol information from it, rather than reading
5141 the symbol table from the executable program. Using the '-mapped'
5142 option in a GDB `file' or `symbol-file' command has the same effect as
5143 starting GDB with the '-mapped' command-line option.
5145 You can cause GDB to read the entire symbol table immediately by using
5146 the '-readnow' option with any of the commands that load symbol table
5147 information (or on the GDB command line). This makes the command
5148 slower, but makes future operations faster.
5150 The -mapped and -readnow options are typically combined in order to
5151 build a `fred.syms' file that contains complete symbol information.
5152 A simple GDB invocation to do nothing but build a `.syms' file for future
5155 gdb -batch -nx -mapped -readnow programname
5157 The `.syms' file is specific to the host machine on which GDB is run.
5158 It holds an exact image of GDB's internal symbol table. It cannot be
5159 shared across multiple host platforms.
5161 * longjmp() handling
5163 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5164 siglongjmp() without losing control. This feature has not yet been ported to
5165 all systems. It currently works on many 386 platforms, all MIPS-based
5166 platforms (SGI, DECstation, etc), and Sun3/4.
5170 Preliminary work has been put in to support the new Solaris OS from Sun. At
5171 this time, it can control and debug processes, but it is not capable of
5176 As always, many many bug fixes. The major areas were with g++, and mipsread.
5177 People using the MIPS-based platforms should experience fewer mysterious
5178 crashes and trashed symbol tables.
5180 *** Changes in GDB-4.4:
5182 * New machines supported (host and target)
5184 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5186 BSD Reno on Vax vax-dec-bsd
5187 Ultrix on Vax vax-dec-ultrix
5189 * New machines supported (target)
5191 AMD 29000 embedded, using EBMON a29k-none-none
5195 GDB continues to improve its handling of C++. `References' work better.
5196 The demangler has also been improved, and now deals with symbols mangled as
5197 per the Annotated C++ Reference Guide.
5199 GDB also now handles `stabs' symbol information embedded in MIPS
5200 `ecoff' symbol tables. Since the ecoff format was not easily
5201 extensible to handle new languages such as C++, this appeared to be a
5202 good way to put C++ debugging info into MIPS binaries. This option
5203 will be supported in the GNU C compiler, version 2, when it is
5206 * New features for SVR4
5208 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5209 shared libraries. Debugging dynamically linked programs should present
5210 only minor differences from debugging statically linked programs.
5212 The `info proc' command will print out information about any process
5213 on an SVR4 system (including the one you are debugging). At the moment,
5214 it prints the address mappings of the process.
5216 If you bring up GDB on another SVR4 system, please send mail to
5217 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5219 * Better dynamic linking support in SunOS
5221 Reading symbols from shared libraries which contain debugging symbols
5222 now works properly. However, there remain issues such as automatic
5223 skipping of `transfer vector' code during function calls, which
5224 make it harder to debug code in a shared library, than to debug the
5225 same code linked statically.
5229 GDB is now using the latest `getopt' routines from the FSF. This
5230 version accepts the -- prefix for options with long names. GDB will
5231 continue to accept the old forms (-option and +option) as well.
5232 Various single letter abbreviations for options have been explicity
5233 added to the option table so that they won't get overshadowed in the
5234 future by other options that begin with the same letter.
5238 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5239 Many assorted bugs have been handled. Many more remain to be handled.
5240 See the various ChangeLog files (primarily in gdb and bfd) for details.
5243 *** Changes in GDB-4.3:
5245 * New machines supported (host and target)
5247 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5248 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5249 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5251 * Almost SCO Unix support
5253 We had hoped to support:
5254 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5255 (except for core file support), but we discovered very late in the release
5256 that it has problems with process groups that render gdb unusable. Sorry
5257 about that. I encourage people to fix it and post the fixes.
5259 * Preliminary ELF and DWARF support
5261 GDB can read ELF object files on System V Release 4, and can handle
5262 debugging records for C, in DWARF format, in ELF files. This support
5263 is preliminary. If you bring up GDB on another SVR4 system, please
5264 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5269 GDB now uses the latest `readline' library. One user-visible change
5270 is that two tabs will list possible command completions, which previously
5271 required typing M-? (meta-question mark, or ESC ?).
5275 The `stepi' bug that many of you noticed has been squashed.
5276 Many bugs in C++ have been handled. Many more remain to be handled.
5277 See the various ChangeLog files (primarily in gdb and bfd) for details.
5279 * State of the MIPS world (in case you wondered):
5281 GDB can understand the symbol tables emitted by the compilers
5282 supplied by most vendors of MIPS-based machines, including DEC. These
5283 symbol tables are in a format that essentially nobody else uses.
5285 Some versions of gcc come with an assembler post-processor called
5286 mips-tfile. This program is required if you want to do source-level
5287 debugging of gcc-compiled programs. I believe FSF does not ship
5288 mips-tfile with gcc version 1, but it will eventually come with gcc
5291 Debugging of g++ output remains a problem. g++ version 1.xx does not
5292 really support it at all. (If you're lucky, you should be able to get
5293 line numbers and stack traces to work, but no parameters or local
5294 variables.) With some work it should be possible to improve the
5297 When gcc version 2 is released, you will have somewhat better luck.
5298 However, even then you will get confusing results for inheritance and
5301 We will eventually provide full debugging of g++ output on
5302 DECstations. This will probably involve some kind of stabs-in-ecoff
5303 encapulation, but the details have not been worked out yet.
5306 *** Changes in GDB-4.2:
5308 * Improved configuration
5310 Only one copy of `configure' exists now, and it is not self-modifying.
5311 Porting BFD is simpler.
5315 The `step' and `next' commands now only stop at the first instruction
5316 of a source line. This prevents the multiple stops that used to occur
5317 in switch statements, for-loops, etc. `Step' continues to stop if a
5318 function that has debugging information is called within the line.
5322 Lots of small bugs fixed. More remain.
5324 * New host supported (not target)
5326 Intel 386 PC clone running Mach i386-none-mach
5329 *** Changes in GDB-4.1:
5331 * Multiple source language support
5333 GDB now has internal scaffolding to handle several source languages.
5334 It determines the type of each source file from its filename extension,
5335 and will switch expression parsing and number formatting to match the
5336 language of the function in the currently selected stack frame.
5337 You can also specifically set the language to be used, with
5338 `set language c' or `set language modula-2'.
5342 GDB now has preliminary support for the GNU Modula-2 compiler,
5343 currently under development at the State University of New York at
5344 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5345 continue through the fall of 1991 and into 1992.
5347 Other Modula-2 compilers are currently not supported, and attempting to
5348 debug programs compiled with them will likely result in an error as the
5349 symbol table is read. Feel free to work on it, though!
5351 There are hooks in GDB for strict type checking and range checking,
5352 in the `Modula-2 philosophy', but they do not currently work.
5356 GDB can now write to executable and core files (e.g. patch
5357 a variable's value). You must turn this switch on, specify
5358 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5359 by assigning a new value to a variable. Modifications take
5362 * Automatic SunOS shared library reading
5364 When you run your program, GDB automatically determines where its
5365 shared libraries (if any) have been loaded, and reads their symbols.
5366 The `share' command is no longer needed. This also works when
5367 examining core files.
5371 You can specify the number of lines that the `list' command shows.
5374 * New machines supported (host and target)
5376 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5377 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5378 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5380 * New hosts supported (not targets)
5382 IBM RT/PC: romp-ibm-aix or rtpc
5384 * New targets supported (not hosts)
5386 AMD 29000 embedded with COFF a29k-none-coff
5387 AMD 29000 embedded with a.out a29k-none-aout
5388 Ultracomputer remote kernel debug a29k-nyu-kern
5390 * New remote interfaces
5396 *** Changes in GDB-4.0:
5400 Wide output is wrapped at good places to make the output more readable.
5402 Gdb now supports cross-debugging from a host machine of one type to a
5403 target machine of another type. Communication with the target system
5404 is over serial lines. The ``target'' command handles connecting to the
5405 remote system; the ``load'' command will download a program into the
5406 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5407 also supports debugging of realtime processes running under VxWorks,
5408 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5409 stub on the target system.
5411 New CPUs supported include the AMD 29000 and Intel 960.
5413 GDB now reads object files and symbol tables via a ``binary file''
5414 library, which allows a single copy of GDB to debug programs of multiple
5415 object file types such as a.out and coff.
5417 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5418 refcard.dvi and refcard.ps are available to format it).
5421 * Control-Variable user interface simplified
5423 All variables that control the operation of the debugger can be set
5424 by the ``set'' command, and displayed by the ``show'' command.
5426 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5427 ``Show prompt'' produces the response:
5428 Gdb's prompt is new-gdb=>.
5430 What follows are the NEW set commands. The command ``help set'' will
5431 print a complete list of old and new set commands. ``help set FOO''
5432 will give a longer description of the variable FOO. ``show'' will show
5433 all of the variable descriptions and their current settings.
5435 confirm on/off: Enables warning questions for operations that are
5436 hard to recover from, e.g. rerunning the program while
5437 it is already running. Default is ON.
5439 editing on/off: Enables EMACS style command line editing
5440 of input. Previous lines can be recalled with
5441 control-P, the current line can be edited with control-B,
5442 you can search for commands with control-R, etc.
5445 history filename NAME: NAME is where the gdb command history
5446 will be stored. The default is .gdb_history,
5447 or the value of the environment variable
5450 history size N: The size, in commands, of the command history. The
5451 default is 256, or the value of the environment variable
5454 history save on/off: If this value is set to ON, the history file will
5455 be saved after exiting gdb. If set to OFF, the
5456 file will not be saved. The default is OFF.
5458 history expansion on/off: If this value is set to ON, then csh-like
5459 history expansion will be performed on
5460 command line input. The default is OFF.
5462 radix N: Sets the default radix for input and output. It can be set
5463 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5464 in the current radix, so "set radix 10" is always a no-op.
5466 height N: This integer value is the number of lines on a page. Default
5467 is 24, the current `stty rows'' setting, or the ``li#''
5468 setting from the termcap entry matching the environment
5471 width N: This integer value is the number of characters on a line.
5472 Default is 80, the current `stty cols'' setting, or the ``co#''
5473 setting from the termcap entry matching the environment
5476 Note: ``set screensize'' is obsolete. Use ``set height'' and
5477 ``set width'' instead.
5479 print address on/off: Print memory addresses in various command displays,
5480 such as stack traces and structure values. Gdb looks
5481 more ``symbolic'' if you turn this off; it looks more
5482 ``machine level'' with it on. Default is ON.
5484 print array on/off: Prettyprint arrays. New convenient format! Default
5487 print demangle on/off: Print C++ symbols in "source" form if on,
5490 print asm-demangle on/off: Same, for assembler level printouts
5493 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5496 * Support for Epoch Environment.
5498 The epoch environment is a version of Emacs v18 with windowing. One
5499 new command, ``inspect'', is identical to ``print'', except that if you
5500 are running in the epoch environment, the value is printed in its own
5504 * Support for Shared Libraries
5506 GDB can now debug programs and core files that use SunOS shared libraries.
5507 Symbols from a shared library cannot be referenced
5508 before the shared library has been linked with the program (this
5509 happens after you type ``run'' and before the function main() is entered).
5510 At any time after this linking (including when examining core files
5511 from dynamically linked programs), gdb reads the symbols from each
5512 shared library when you type the ``sharedlibrary'' command.
5513 It can be abbreviated ``share''.
5515 sharedlibrary REGEXP: Load shared object library symbols for files
5516 matching a unix regular expression. No argument
5517 indicates to load symbols for all shared libraries.
5519 info sharedlibrary: Status of loaded shared libraries.
5524 A watchpoint stops execution of a program whenever the value of an
5525 expression changes. Checking for this slows down execution
5526 tremendously whenever you are in the scope of the expression, but is
5527 quite useful for catching tough ``bit-spreader'' or pointer misuse
5528 problems. Some machines such as the 386 have hardware for doing this
5529 more quickly, and future versions of gdb will use this hardware.
5531 watch EXP: Set a watchpoint (breakpoint) for an expression.
5533 info watchpoints: Information about your watchpoints.
5535 delete N: Deletes watchpoint number N (same as breakpoints).
5536 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5537 enable N: Re-enables watchpoint number N (same as breakpoints).
5540 * C++ multiple inheritance
5542 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5545 * C++ exception handling
5547 Gdb now supports limited C++ exception handling. Besides the existing
5548 ability to breakpoint on an exception handler, gdb can breakpoint on
5549 the raising of an exception (before the stack is peeled back to the
5552 catch FOO: If there is a FOO exception handler in the dynamic scope,
5553 set a breakpoint to catch exceptions which may be raised there.
5554 Multiple exceptions (``catch foo bar baz'') may be caught.
5556 info catch: Lists all exceptions which may be caught in the
5557 current stack frame.
5560 * Minor command changes
5562 The command ``call func (arg, arg, ...)'' now acts like the print
5563 command, except it does not print or save a value if the function's result
5564 is void. This is similar to dbx usage.
5566 The ``up'' and ``down'' commands now always print the frame they end up
5567 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5568 frames without printing.
5570 * New directory command
5572 'dir' now adds directories to the FRONT of the source search path.
5573 The path starts off empty. Source files that contain debug information
5574 about the directory in which they were compiled can be found even
5575 with an empty path; Sun CC and GCC include this information. If GDB can't
5576 find your source file in the current directory, type "dir .".
5578 * Configuring GDB for compilation
5580 For normal use, type ``./configure host''. See README or gdb.texinfo
5583 GDB now handles cross debugging. If you are remotely debugging between
5584 two different machines, type ``./configure host -target=targ''.
5585 Host is the machine where GDB will run; targ is the machine
5586 where the program that you are debugging will run.
5588 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.