1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.7
8 GDB now has support for scripting using Guile. Whether this is
9 available is determined at configure time.
10 Guile version 2.0 or greater is required.
11 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
13 * New commands (for set/show, see "New options" below)
17 Invoke CODE by passing it to the Guile interpreter.
21 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
23 info auto-load guile-scripts [regexp]
24 Print the list of automatically loaded Guile scripts.
26 * The source command is now capable of sourcing Guile scripts.
27 This feature is dependent on the debugger being built with Guile support.
31 set guile print-stack (none|message|full)
32 show guile print-stack
33 Show a stack trace when an error is encountered in a Guile script.
35 set auto-load guile-scripts (on|off)
36 show auto-load guile-scripts
37 Control auto-loading of Guile script files.
39 maint ada set ignore-descriptive-types (on|off)
40 maint ada show ignore-descriptive-types
41 Control whether the debugger should ignore descriptive types in Ada
42 programs. The default is not to ignore the descriptive types. See
43 the user manual for more details on descriptive types and the intended
46 * New features in the GDB remote stub, GDBserver
48 ** New option --debug-format=option1[,option2,...] allows one to add
49 additional text to each output. At present only timestamps
50 are supported: --debug-format=timestamps.
51 Timestamps can also be turned on with the
52 "monitor set debug-format timestamps" command from GDB.
54 * The 'record instruction-history' command now starts counting instructions
55 at one. This also affects the instruction ranges reported by the
56 'record function-call-history' command when given the /i modifier.
58 * The command 'record function-call-history' supports a new modifier '/c' to
59 indent the function names based on their call stack depth.
60 The fields for the '/i' and '/l' modifier have been reordered.
61 The source line range is now prefixed with 'at'.
62 The instruction range is now prefixed with 'inst'.
63 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
64 "record instruction-history" and "list" commands.
66 * The ranges given as arguments to the 'record function-call-history' and
67 'record instruction-history' commands are now inclusive.
69 * The btrace record target now supports the 'record goto' command.
70 For locations inside the execution trace, the back trace is computed
71 based on the information stored in the execution trace.
73 * The btrace record target supports limited reverse execution and replay.
74 The target does not record data and therefore does not allow reading
77 * The "catch syscall" command now works on s390*-linux* targets.
81 qXfer:btrace:read's annex
82 The qXfer:btrace:read packet supports a new annex 'delta' to read
83 branch trace incrementally.
87 ** Valid Python operations on gdb.Value objects representing
88 structs/classes invoke the corresponding overloaded operators if
92 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
94 *** Changes in GDB 7.7
96 * Improved support for process record-replay and reverse debugging on
97 arm*-linux* targets. Support for thumb32 and syscall instruction
98 recording has been added.
100 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
102 * GDB now supports Fission DWP file format version 2.
103 http://gcc.gnu.org/wiki/DebugFission
105 * New convenience function "$_isvoid", to check whether an expression
106 is void. A void expression is an expression where the type of the
107 result is "void". For example, some convenience variables may be
108 "void" when evaluated (e.g., "$_exitcode" before the execution of
109 the program being debugged; or an undefined convenience variable).
110 Another example, when calling a function whose return type is
113 * The "maintenance print objfiles" command now takes an optional regexp.
115 * The "catch syscall" command now works on arm*-linux* targets.
117 * GDB now consistently shows "<not saved>" when printing values of
118 registers the debug info indicates have not been saved in the frame
119 and there's nowhere to retrieve them from
120 (callee-saved/call-clobbered registers):
125 (gdb) info registers rax
128 Before, the former would print "<optimized out>", and the latter
129 "*value not available*".
131 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
136 ** Frame filters and frame decorators have been added.
137 ** Temporary breakpoints are now supported.
138 ** Line tables representation has been added.
139 ** New attribute 'parent_type' for gdb.Field objects.
140 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
141 ** New attribute 'name' for gdb.Type objects.
145 Nios II ELF nios2*-*-elf
146 Nios II GNU/Linux nios2*-*-linux
147 Texas Instruments MSP430 msp430*-*-elf
149 * Removed native configurations
151 Support for these a.out NetBSD and OpenBSD obsolete configurations has
152 been removed. ELF variants of these configurations are kept supported.
154 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
155 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
156 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
157 i[34567]86-*-openbsd3.[0-3]
158 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
159 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
160 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
164 Like "catch throw", but catches a re-thrown exception.
166 Renamed from old "maint check-symtabs".
168 Perform consistency checks on symtabs.
170 Expand symtabs matching an optional regexp.
173 Display the details of GDB configure-time options.
175 maint set|show per-command
176 maint set|show per-command space
177 maint set|show per-command time
178 maint set|show per-command symtab
179 Enable display of per-command gdb resource usage.
181 remove-symbol-file FILENAME
182 remove-symbol-file -a ADDRESS
183 Remove a symbol file added via add-symbol-file. The file to remove
184 can be identified by its filename or by an address that lies within
185 the boundaries of this symbol file in memory.
188 info exceptions REGEXP
189 Display the list of Ada exceptions defined in the program being
190 debugged. If provided, only the exceptions whose names match REGEXP
195 set debug symfile off|on
197 Control display of debugging info regarding reading symbol files and
198 symbol tables within those files
200 set print raw frame-arguments
201 show print raw frame-arguments
202 Set/show whether to print frame arguments in raw mode,
203 disregarding any defined pretty-printers.
205 set remote trace-status-packet
206 show remote trace-status-packet
207 Set/show the use of remote protocol qTStatus packet.
211 Control display of debugging messages related to Nios II targets.
215 Control whether target-assisted range stepping is enabled.
217 set startup-with-shell
218 show startup-with-shell
219 Specifies whether Unix child processes are started via a shell or
224 Use the target memory cache for accesses to the code segment. This
225 improves performance of remote debugging (particularly disassembly).
227 * You can now use a literal value 'unlimited' for options that
228 interpret 0 or -1 as meaning "unlimited". E.g., "set
229 trace-buffer-size unlimited" is now an alias for "set
230 trace-buffer-size -1" and "set height unlimited" is now an alias for
233 * The "set debug symtab-create" debugging option of GDB has been changed to
234 accept a verbosity level. 0 means "off", 1 provides basic debugging
235 output, and values of 2 or greater provides more verbose output.
237 * New command-line options
239 Display the details of GDB configure-time options.
241 * The command 'tsave' can now support new option '-ctf' to save trace
242 buffer in Common Trace Format.
244 * Newly installed $prefix/bin/gcore acts as a shell interface for the
247 * GDB now implements the the C++ 'typeid' operator.
249 * The new convenience variable $_exception holds the exception being
250 thrown or caught at an exception-related catchpoint.
252 * The exception-related catchpoints, like "catch throw", now accept a
253 regular expression which can be used to filter exceptions by type.
255 * The new convenience variable $_exitsignal is automatically set to
256 the terminating signal number when the program being debugged dies
257 due to an uncaught signal.
261 ** All MI commands now accept an optional "--language" option.
262 Support for this feature can be verified by using the "-list-features"
263 command, which should contain "language-option".
265 ** The new command -info-gdb-mi-command allows the user to determine
266 whether a GDB/MI command is supported or not.
268 ** The "^error" result record returned when trying to execute an undefined
269 GDB/MI command now provides a variable named "code" whose content is the
270 "undefined-command" error code. Support for this feature can be verified
271 by using the "-list-features" command, which should contain
272 "undefined-command-error-code".
274 ** The -trace-save MI command can optionally save trace buffer in Common
277 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
279 ** The command -data-list-register-values now accepts an optional
280 "--skip-unavailable" option. When used, only the available registers
283 ** The new command -trace-frame-collected dumps collected variables,
284 computed expressions, tvars, memory and registers in a traceframe.
286 ** The commands -stack-list-locals, -stack-list-arguments and
287 -stack-list-variables now accept an option "--skip-unavailable".
288 When used, only the available locals or arguments are displayed.
290 ** The -exec-run command now accepts an optional "--start" option.
291 When used, the command follows the same semantics as the "start"
292 command, stopping the program's execution at the start of its
293 main subprogram. Support for this feature can be verified using
294 the "-list-features" command, which should contain
295 "exec-run-start-option".
297 ** The new commands -catch-assert and -catch-exceptions insert
298 catchpoints stopping the program when Ada exceptions are raised.
300 ** The new command -info-ada-exceptions provides the equivalent of
301 the new "info exceptions" command.
303 * New system-wide configuration scripts
304 A GDB installation now provides scripts suitable for use as system-wide
305 configuration scripts for the following systems:
309 * GDB now supports target-assigned range stepping with remote targets.
310 This improves the performance of stepping source lines by reducing
311 the number of control packets from/to GDB. See "New remote packets"
314 * GDB now understands the element 'tvar' in the XML traceframe info.
315 It has the id of the collected trace state variables.
317 * On S/390 targets that provide the transactional-execution feature,
318 the program interruption transaction diagnostic block (TDB) is now
319 represented as a number of additional "registers" in GDB.
325 The vCont packet supports a new 'r' action, that tells the remote
326 stub to step through an address range itself, without GDB
327 involvemement at each single-step.
329 qXfer:libraries-svr4:read's annex
330 The previously unused annex of the qXfer:libraries-svr4:read packet
331 is now used to support passing an argument list. The remote stub
332 reports support for this argument list to GDB's qSupported query.
333 The defined arguments are "start" and "prev", used to reduce work
334 necessary for library list updating, resulting in significant
337 * New features in the GDB remote stub, GDBserver
339 ** GDBserver now supports target-assisted range stepping. Currently
340 enabled on x86/x86_64 GNU/Linux targets.
342 ** GDBserver now adds element 'tvar' in the XML in the reply to
343 'qXfer:traceframe-info:read'. It has the id of the collected
344 trace state variables.
346 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
349 * New 'z' formatter for printing and examining memory, this displays the
350 value as hexadecimal zero padded on the left to the size of the type.
352 * GDB can now use Windows x64 unwinding data.
354 * The "set remotebaud" command has been replaced by "set serial baud".
355 Similarly, "show remotebaud" has been replaced by "show serial baud".
356 The "set remotebaud" and "show remotebaud" commands are still available
357 to provide backward compatibility with older versions of GDB.
359 *** Changes in GDB 7.6
361 * Target record has been renamed to record-full.
362 Record/replay is now enabled with the "record full" command.
363 This also affects settings that are associated with full record/replay
364 that have been moved from "set/show record" to "set/show record full":
366 set|show record full insn-number-max
367 set|show record full stop-at-limit
368 set|show record full memory-query
370 * A new record target "record-btrace" has been added. The new target
371 uses hardware support to record the control-flow of a process. It
372 does not support replaying the execution, but it implements the
373 below new commands for investigating the recorded execution log.
374 This new recording method can be enabled using:
378 The "record-btrace" target is only available on Intel Atom processors
379 and requires a Linux kernel 2.6.32 or later.
381 * Two new commands have been added for record/replay to give information
382 about the recorded execution without having to replay the execution.
383 The commands are only supported by "record btrace".
385 record instruction-history prints the execution history at
386 instruction granularity
388 record function-call-history prints the execution history at
391 * New native configurations
393 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
394 FreeBSD/powerpc powerpc*-*-freebsd
395 x86_64/Cygwin x86_64-*-cygwin*
396 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
400 ARM AArch64 aarch64*-*-elf
401 ARM AArch64 GNU/Linux aarch64*-*-linux
402 Lynx 178 PowerPC powerpc-*-lynx*178
403 x86_64/Cygwin x86_64-*-cygwin*
404 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
406 * If the configured location of system.gdbinit file (as given by the
407 --with-system-gdbinit option at configure time) is in the
408 data-directory (as specified by --with-gdb-datadir at configure
409 time) or in one of its subdirectories, then GDB will look for the
410 system-wide init file in the directory specified by the
411 --data-directory command-line option.
413 * New command line options:
415 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
416 other initialization files, unlike -nx which disables all of them.
418 * Removed command line options
420 -epoch This was used by the gdb mode in Epoch, an ancient fork of
423 * The 'ptype' and 'whatis' commands now accept an argument to control
426 * 'info proc' now works on some core files.
430 ** Vectors can be created with gdb.Type.vector.
432 ** Python's atexit.register now works in GDB.
434 ** Types can be pretty-printed via a Python API.
436 ** Python 3 is now supported (in addition to Python 2.4 or later)
438 ** New class gdb.Architecture exposes GDB's internal representation
439 of architecture in the Python API.
441 ** New method Frame.architecture returns the gdb.Architecture object
442 corresponding to the frame's architecture.
444 * New Python-based convenience functions:
446 ** $_memeq(buf1, buf2, length)
447 ** $_streq(str1, str2)
449 ** $_regex(str, regex)
451 * The 'cd' command now defaults to using '~' (the home directory) if not
454 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
455 default for GCC since November 2000.
457 * The command 'forward-search' can now be abbreviated as 'fo'.
459 * The command 'info tracepoints' can now display 'installed on target'
460 or 'not installed on target' for each non-pending location of tracepoint.
462 * New configure options
464 --enable-libmcheck/--disable-libmcheck
465 By default, development versions are built with -lmcheck on hosts
466 that support it, in order to help track memory corruption issues.
467 Release versions, on the other hand, are built without -lmcheck
468 by default. The --enable-libmcheck/--disable-libmcheck configure
469 options allow the user to override that default.
470 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
471 This configure option allows the user to build GDB with
472 libbabeltrace using which GDB can read Common Trace Format data.
474 * New commands (for set/show, see "New options" below)
477 Catch signals. This is similar to "handle", but allows commands and
478 conditions to be attached.
481 List the BFDs known to GDB.
483 python-interactive [command]
485 Start a Python interactive prompt, or evaluate the optional command
486 and print the result of expressions.
489 "py" is a new alias for "python".
491 enable type-printer [name]...
492 disable type-printer [name]...
493 Enable or disable type printers.
497 ** For the Renesas Super-H architecture, the "regs" command has been removed
498 (has been deprecated in GDB 7.5), and "info all-registers" should be used
503 set print type methods (on|off)
504 show print type methods
505 Control whether method declarations are displayed by "ptype".
506 The default is to show them.
508 set print type typedefs (on|off)
509 show print type typedefs
510 Control whether typedef definitions are displayed by "ptype".
511 The default is to show them.
513 set filename-display basename|relative|absolute
514 show filename-display
515 Control the way in which filenames is displayed.
516 The default is "relative", which preserves previous behavior.
518 set trace-buffer-size
519 show trace-buffer-size
520 Request target to change the size of trace buffer.
522 set remote trace-buffer-size-packet auto|on|off
523 show remote trace-buffer-size-packet
524 Control the use of the remote protocol `QTBuffer:size' packet.
528 Control display of debugging messages related to ARM AArch64.
531 set debug coff-pe-read
532 show debug coff-pe-read
533 Control display of debugging messages related to reading of COFF/PE
538 Control display of debugging messages related to Mach-O symbols
541 set debug notification
542 show debug notification
543 Control display of debugging info for async remote notification.
547 ** Command parameter changes are now notified using new async record
548 "=cmd-param-changed".
549 ** Trace frame changes caused by command "tfind" are now notified using
550 new async record "=traceframe-changed".
551 ** The creation, deletion and modification of trace state variables
552 are now notified using new async records "=tsv-created",
553 "=tsv-deleted" and "=tsv-modified".
554 ** The start and stop of process record are now notified using new
555 async record "=record-started" and "=record-stopped".
556 ** Memory changes are now notified using new async record
558 ** The data-disassemble command response will include a "fullname" field
559 containing the absolute file name when source has been requested.
560 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
561 command, to allow pattern filling of memory areas.
562 ** New commands "-catch-load"/"-catch-unload" added for intercepting
563 library load/unload events.
564 ** The response to breakpoint commands and breakpoint async records
565 includes an "installed" field containing a boolean state about each
566 non-pending tracepoint location is whether installed on target or not.
567 ** Output of the "-trace-status" command includes a "trace-file" field
568 containing the name of the trace file being examined. This field is
569 optional, and only present when examining a trace file.
570 ** The "fullname" field is now always present along with the "file" field,
571 even if the file cannot be found by GDB.
573 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
574 You must have the LZMA library available when configuring GDB for this
575 feature to be enabled. For more information, see:
576 http://fedoraproject.org/wiki/Features/MiniDebugInfo
581 Set the size of trace buffer. The remote stub reports support for this
582 packet to gdb's qSupported query.
585 Enable Branch Trace Store (BTS)-based branch tracing for the current
586 thread. The remote stub reports support for this packet to gdb's
590 Disable branch tracing for the current thread. The remote stub reports
591 support for this packet to gdb's qSupported query.
594 Read the traced branches for the current thread. The remote stub
595 reports support for this packet to gdb's qSupported query.
597 *** Changes in GDB 7.5
599 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
600 for more x32 ABI info.
602 * GDB now supports access to MIPS DSP registers on Linux targets.
604 * GDB now supports debugging microMIPS binaries.
606 * The "info os" command on GNU/Linux can now display information on
607 several new classes of objects managed by the operating system:
608 "info os procgroups" lists process groups
609 "info os files" lists file descriptors
610 "info os sockets" lists internet-domain sockets
611 "info os shm" lists shared-memory regions
612 "info os semaphores" lists semaphores
613 "info os msg" lists message queues
614 "info os modules" lists loaded kernel modules
616 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
617 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
618 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
619 options and inspect the probe arguments using the new $_probe_arg family
620 of convenience variables. You can obtain more information about SystemTap
621 in <http://sourceware.org/systemtap/>.
623 * GDB now supports reversible debugging on ARM, it allows you to
624 debug basic ARM and THUMB instructions, and provides
625 record/replay support.
627 * The option "symbol-reloading" has been deleted as it is no longer used.
631 ** GDB commands implemented in Python can now be put in command class
634 ** The "maint set python print-stack on|off" is now deleted.
636 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
637 apply "flag enum"-style pretty-printing to any enum.
639 ** gdb.lookup_symbol can now work when there is no current frame.
641 ** gdb.Symbol now has a 'line' attribute, holding the line number in
642 the source at which the symbol was defined.
644 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
645 method 'value'. The former indicates whether the symbol needs a
646 frame in order to compute its value, and the latter computes the
649 ** A new method 'referenced_value' on gdb.Value objects which can
650 dereference pointer as well as C++ reference values.
652 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
653 which return the global and static blocks (as gdb.Block objects),
654 of the underlying symbol table, respectively.
656 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
657 object associated with a PC value.
659 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
660 of the address range occupied by code for the current source line.
662 * Go language support.
663 GDB now supports debugging programs written in the Go programming
666 * GDBserver now supports stdio connections.
667 E.g. (gdb) target remote | ssh myhost gdbserver - hello
669 * The binary "gdbtui" can no longer be built or installed.
670 Use "gdb -tui" instead.
672 * GDB will now print "flag" enums specially. A flag enum is one where
673 all the enumerator values have no bits in common when pairwise
674 "and"ed. When printing a value whose type is a flag enum, GDB will
675 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
676 (gdb) print (enum E) 3
679 * The filename part of a linespec will now match trailing components
680 of a source file name. For example, "break gcc/expr.c:1000" will
681 now set a breakpoint in build/gcc/expr.c, but not
684 * The "info proc" and "generate-core-file" commands will now also
685 work on remote targets connected to GDBserver on Linux.
687 * The command "info catch" has been removed. It has been disabled
690 * The "catch exception" and "catch assert" commands now accept
691 a condition at the end of the command, much like the "break"
692 command does. For instance:
694 (gdb) catch exception Constraint_Error if Barrier = True
696 Previously, it was possible to add a condition to such catchpoints,
697 but it had to be done as a second step, after the catchpoint had been
698 created, using the "condition" command.
700 * The "info static-tracepoint-marker" command will now also work on
701 native Linux targets with in-process agent.
703 * GDB can now set breakpoints on inlined functions.
705 * The .gdb_index section has been updated to include symbols for
706 inlined functions. GDB will ignore older .gdb_index sections by
707 default, which could cause symbol files to be loaded more slowly
708 until their .gdb_index sections can be recreated. The new command
709 "set use-deprecated-index-sections on" will cause GDB to use any older
710 .gdb_index sections it finds. This will restore performance, but the
711 ability to set breakpoints on inlined functions will be lost in symbol
712 files with older .gdb_index sections.
714 The .gdb_index section has also been updated to record more information
715 about each symbol. This speeds up the "info variables", "info functions"
716 and "info types" commands when used with programs having the .gdb_index
717 section, as well as speeding up debugging with shared libraries using
718 the .gdb_index section.
720 * Ada support for GDB/MI Variable Objects has been added.
722 * GDB can now support 'breakpoint always-inserted mode' in 'record'
727 ** New command -info-os is the MI equivalent of "info os".
729 ** Output logs ("set logging" and related) now include MI output.
733 ** "set use-deprecated-index-sections on|off"
734 "show use-deprecated-index-sections on|off"
735 Controls the use of deprecated .gdb_index sections.
737 ** "catch load" and "catch unload" can be used to stop when a shared
738 library is loaded or unloaded, respectively.
740 ** "enable count" can be used to auto-disable a breakpoint after
743 ** "info vtbl" can be used to show the virtual method tables for
744 C++ and Java objects.
746 ** "explore" and its sub commands "explore value" and "explore type"
747 can be used to recursively explore values and types of
748 expressions. These commands are available only if GDB is
749 configured with '--with-python'.
751 ** "info auto-load" shows status of all kinds of auto-loaded files,
752 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
753 sequences of commands files, "info auto-load python-scripts"
754 shows status of auto-loading Python script files,
755 "info auto-load local-gdbinit" shows status of loading init file
756 (.gdbinit) from current directory and "info auto-load libthread-db" shows
757 status of inferior specific thread debugging shared library loading.
759 ** "info auto-load-scripts", "set auto-load-scripts on|off"
760 and "show auto-load-scripts" commands have been deprecated, use their
761 "info auto-load python-scripts", "set auto-load python-scripts on|off"
762 and "show auto-load python-scripts" counterparts instead.
764 ** "dprintf location,format,args..." creates a dynamic printf, which
765 is basically a breakpoint that does a printf and immediately
766 resumes your program's execution, so it is like a printf that you
767 can insert dynamically at runtime instead of at compiletime.
769 ** "set print symbol"
771 Controls whether GDB attempts to display the symbol, if any,
772 corresponding to addresses it prints. This defaults to "on", but
773 you can set it to "off" to restore GDB's previous behavior.
775 * Deprecated commands
777 ** For the Renesas Super-H architecture, the "regs" command has been
778 deprecated, and "info all-registers" should be used instead.
782 Renesas RL78 rl78-*-elf
783 HP OpenVMS ia64 ia64-hp-openvms*
785 * GDBserver supports evaluation of breakpoint conditions. When
786 support is advertised by GDBserver, GDB may be told to send the
787 breakpoint conditions in bytecode form to GDBserver. GDBserver
788 will only report the breakpoint trigger to GDB when its condition
794 show mips compression
795 Select the compressed ISA encoding used in functions that have no symbol
796 information available. The encoding can be set to either of:
799 and is updated automatically from ELF file flags if available.
801 set breakpoint condition-evaluation
802 show breakpoint condition-evaluation
803 Control whether breakpoint conditions are evaluated by GDB ("host") or by
804 GDBserver ("target"). Default option "auto" chooses the most efficient
806 This option can improve debugger efficiency depending on the speed of the
810 Disable auto-loading globally.
813 Show auto-loading setting of all kinds of auto-loaded files.
815 set auto-load gdb-scripts on|off
816 show auto-load gdb-scripts
817 Control auto-loading of GDB canned sequences of commands files.
819 set auto-load python-scripts on|off
820 show auto-load python-scripts
821 Control auto-loading of Python script files.
823 set auto-load local-gdbinit on|off
824 show auto-load local-gdbinit
825 Control loading of init file (.gdbinit) from current directory.
827 set auto-load libthread-db on|off
828 show auto-load libthread-db
829 Control auto-loading of inferior specific thread debugging shared library.
831 set auto-load scripts-directory <dir1>[:<dir2>...]
832 show auto-load scripts-directory
833 Set a list of directories from which to load auto-loaded scripts.
834 Automatically loaded Python scripts and GDB scripts are located in one
835 of the directories listed by this option.
836 The delimiter (':' above) may differ according to the host platform.
838 set auto-load safe-path <dir1>[:<dir2>...]
839 show auto-load safe-path
840 Set a list of directories from which it is safe to auto-load files.
841 The delimiter (':' above) may differ according to the host platform.
843 set debug auto-load on|off
845 Control display of debugging info for auto-loading the files above.
847 set dprintf-style gdb|call|agent
849 Control the way in which a dynamic printf is performed; "gdb"
850 requests a GDB printf command, while "call" causes dprintf to call a
851 function in the inferior. "agent" requests that the target agent
852 (such as GDBserver) do the printing.
854 set dprintf-function <expr>
855 show dprintf-function
856 set dprintf-channel <expr>
858 Set the function and optional first argument to the call when using
859 the "call" style of dynamic printf.
861 set disconnected-dprintf on|off
862 show disconnected-dprintf
863 Control whether agent-style dynamic printfs continue to be in effect
864 after GDB disconnects.
866 * New configure options
869 Configure default value for the 'set auto-load scripts-directory'
870 setting above. It defaults to '$debugdir:$datadir/auto-load',
871 $debugdir representing global debugging info directories (available
872 via 'show debug-file-directory') and $datadir representing GDB's data
873 directory (available via 'show data-directory').
875 --with-auto-load-safe-path
876 Configure default value for the 'set auto-load safe-path' setting
877 above. It defaults to the --with-auto-load-dir setting.
879 --without-auto-load-safe-path
880 Set 'set auto-load safe-path' to '/', effectively disabling this
885 z0/z1 conditional breakpoints extension
887 The z0/z1 breakpoint insertion packets have been extended to carry
888 a list of conditional expressions over to the remote stub depending on the
889 condition evaluation mode. The use of this extension can be controlled
890 via the "set remote conditional-breakpoints-packet" command.
894 Specify the signals which the remote stub may pass to the debugged
895 program without GDB involvement.
897 * New command line options
899 --init-command=FILE, -ix Like --command, -x but execute it
900 before loading inferior.
901 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
902 execute it before loading inferior.
904 *** Changes in GDB 7.4
906 * GDB now handles ambiguous linespecs more consistently; the existing
907 FILE:LINE support has been expanded to other types of linespecs. A
908 breakpoint will now be set on all matching locations in all
909 inferiors, and locations will be added or removed according to
912 * GDB now allows you to skip uninteresting functions and files when
913 stepping with the "skip function" and "skip file" commands.
915 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
916 and "show remote hardware-watchpoint-length-limit". These allows to
917 set or show the maximum length limit (in bytes) of a remote
918 target hardware watchpoint.
920 This allows e.g. to use "unlimited" hardware watchpoints with the
921 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
922 watchpoints are slower than real hardware watchpoints but are
923 significantly faster than gdb software watchpoints.
927 ** The register_pretty_printer function in module gdb.printing now takes
928 an optional `replace' argument. If True, the new printer replaces any
931 ** The "maint set python print-stack on|off" command has been
932 deprecated and will be deleted in GDB 7.5.
933 A new command: "set python print-stack none|full|message" has
934 replaced it. Additionally, the default for "print-stack" is
935 now "message", which just prints the error message without
938 ** A prompt substitution hook (prompt_hook) is now available to the
941 ** A new Python module, gdb.prompt has been added to the GDB Python
942 modules library. This module provides functionality for
943 escape sequences in prompts (used by set/show
944 extended-prompt). These escape sequences are replaced by their
947 ** Python commands and convenience-functions located in
948 'data-directory'/python/gdb/command and
949 'data-directory'/python/gdb/function are now automatically loaded
952 ** Blocks now provide four new attributes. global_block and
953 static_block will return the global and static blocks
954 respectively. is_static and is_global are boolean attributes
955 that indicate if the block is one of those two types.
957 ** Symbols now provide the "type" attribute, the type of the symbol.
959 ** The "gdb.breakpoint" function has been deprecated in favor of
962 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
963 of a function. This class is based on the "finish" command
964 available in the CLI.
966 ** Type objects for struct and union types now allow access to
967 the fields using standard Python dictionary (mapping) methods.
968 For example, "some_type['myfield']" now works, as does
971 ** A new event "gdb.new_objfile" has been added, triggered by loading a
974 ** A new function, "deep_items" has been added to the gdb.types
975 module in the GDB Python modules library. This function returns
976 an iterator over the fields of a struct or union type. Unlike
977 the standard Python "iteritems" method, it will recursively traverse
978 any anonymous fields.
982 ** "*stopped" events can report several new "reason"s, such as
985 ** Breakpoint changes are now notified using new async records, like
986 "=breakpoint-modified".
988 ** New command -ada-task-info.
990 * libthread-db-search-path now supports two special values: $sdir and $pdir.
991 $sdir specifies the default system locations of shared libraries.
992 $pdir specifies the directory where the libpthread used by the application
995 GDB no longer looks in $sdir and $pdir after it has searched the directories
996 mentioned in libthread-db-search-path. If you want to search those
997 directories, they must be specified in libthread-db-search-path.
998 The default value of libthread-db-search-path on GNU/Linux and Solaris
999 systems is now "$sdir:$pdir".
1001 $pdir is not supported by gdbserver, it is currently ignored.
1002 $sdir is supported by gdbserver.
1004 * New configure option --with-iconv-bin.
1005 When using the internationalization support like the one in the GNU C
1006 library, GDB will invoke the "iconv" program to get a list of supported
1007 character sets. If this program lives in a non-standard location, one can
1008 use this option to specify where to find it.
1010 * When natively debugging programs on PowerPC BookE processors running
1011 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1012 watchpoints, which specify a mask in addition to an address to watch.
1013 The mask specifies that some bits of an address (the bits which are
1014 reset in the mask) should be ignored when matching the address accessed
1015 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1016 section in the user manual for more details.
1018 * The new option --once causes GDBserver to stop listening for connections once
1019 the first connection is made. The listening port used by GDBserver will
1020 become available after that.
1022 * New commands "info macros" and "alias" have been added.
1024 * New function parameters suffix @entry specifies value of function parameter
1025 at the time the function got called. Entry values are available only since
1031 "!" is now an alias of the "shell" command.
1032 Note that no space is needed between "!" and SHELL COMMAND.
1036 watch EXPRESSION mask MASK_VALUE
1037 The watch command now supports the mask argument which allows creation
1038 of masked watchpoints, if the current architecture supports this feature.
1040 info auto-load-scripts [REGEXP]
1041 This command was formerly named "maintenance print section-scripts".
1042 It is now generally useful and is no longer a maintenance-only command.
1044 info macro [-all] [--] MACRO
1045 The info macro command has new options `-all' and `--'. The first for
1046 printing all definitions of a macro. The second for explicitly specifying
1047 the end of arguments and the beginning of the macro name in case the macro
1048 name starts with a hyphen.
1050 collect[/s] EXPRESSIONS
1051 The tracepoint collect command now takes an optional modifier "/s"
1052 that directs it to dereference pointer-to-character types and
1053 collect the bytes of memory up to a zero byte. The behavior is
1054 similar to what you see when you use the regular print command on a
1055 string. An optional integer following the "/s" sets a bound on the
1056 number of bytes that will be collected.
1059 The trace start command now interprets any supplied arguments as a
1060 note to be recorded with the trace run, with an effect similar to
1061 setting the variable trace-notes.
1064 The trace stop command now interprets any arguments as a note to be
1065 mentioned along with the tstatus report that the trace was stopped
1066 with a command. The effect is similar to setting the variable
1069 * Tracepoints can now be enabled and disabled at any time after a trace
1070 experiment has been started using the standard "enable" and "disable"
1071 commands. It is now possible to start a trace experiment with no enabled
1072 tracepoints; GDB will display a warning, but will allow the experiment to
1073 begin, assuming that tracepoints will be enabled as needed while the trace
1076 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1077 locations with 4-byte instructions, when they were previously
1078 limited to locations with instructions of 5 bytes or longer.
1082 set debug dwarf2-read
1083 show debug dwarf2-read
1084 Turns on or off display of debugging messages related to reading
1085 DWARF debug info. The default is off.
1087 set debug symtab-create
1088 show debug symtab-create
1089 Turns on or off display of debugging messages related to symbol table
1090 creation. The default is off.
1093 show extended-prompt
1094 Set the GDB prompt, and allow escape sequences to be inserted to
1095 display miscellaneous information (see 'help set extended-prompt'
1096 for the list of sequences). This prompt (and any information
1097 accessed through the escape sequences) is updated every time the
1098 prompt is displayed.
1100 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1101 show print entry-values
1102 Set printing of frame argument values at function entry. In some cases
1103 GDB can determine the value of function argument which was passed by the
1104 function caller, even if the value was modified inside the called function.
1106 set debug entry-values
1107 show debug entry-values
1108 Control display of debugging info for determining frame argument values at
1109 function entry and virtual tail call frames.
1111 set basenames-may-differ
1112 show basenames-may-differ
1113 Set whether a source file may have multiple base names.
1114 (A "base name" is the name of a file with the directory part removed.
1115 Example: The base name of "/home/user/hello.c" is "hello.c".)
1116 If set, GDB will canonicalize file names (e.g., expand symlinks)
1117 before comparing them. Canonicalization is an expensive operation,
1118 but it allows the same file be known by more than one base name.
1119 If not set (the default), all source files are assumed to have just
1120 one base name, and gdb will do file name comparisons more efficiently.
1126 Set a user name and notes for the current and any future trace runs.
1127 This is useful for long-running and/or disconnected traces, to
1128 inform others (or yourself) as to who is running the trace, supply
1129 contact information, or otherwise explain what is going on.
1131 set trace-stop-notes
1132 show trace-stop-notes
1133 Set a note attached to the trace run, that is displayed when the
1134 trace has been stopped by a tstop command. This is useful for
1135 instance as an explanation, if you are stopping a trace run that was
1136 started by someone else.
1138 * New remote packets
1142 Dynamically enable a tracepoint in a started trace experiment.
1146 Dynamically disable a tracepoint in a started trace experiment.
1150 Set the user and notes of the trace run.
1154 Query the current status of a tracepoint.
1158 Query the minimum length of instruction at which a fast tracepoint may
1161 * Dcache size (number of lines) and line-size are now runtime-configurable
1162 via "set dcache line" and "set dcache line-size" commands.
1166 Texas Instruments TMS320C6x tic6x-*-*
1170 Renesas RL78 rl78-*-elf
1172 *** Changes in GDB 7.3.1
1174 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1176 *** Changes in GDB 7.3
1178 * GDB has a new command: "thread find [REGEXP]".
1179 It finds the thread id whose name, target id, or thread extra info
1180 matches the given regular expression.
1182 * The "catch syscall" command now works on mips*-linux* targets.
1184 * The -data-disassemble MI command now supports modes 2 and 3 for
1185 dumping the instruction opcodes.
1187 * New command line options
1189 -data-directory DIR Specify DIR as the "data-directory".
1190 This is mostly for testing purposes.
1192 * The "maint set python auto-load on|off" command has been renamed to
1193 "set auto-load-scripts on|off".
1195 * GDB has a new command: "set directories".
1196 It is like the "dir" command except that it replaces the
1197 source path list instead of augmenting it.
1199 * GDB now understands thread names.
1201 On GNU/Linux, "info threads" will display the thread name as set by
1202 prctl or pthread_setname_np.
1204 There is also a new command, "thread name", which can be used to
1205 assign a name internally for GDB to display.
1208 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1209 has been integrated into GDB.
1213 ** The function gdb.Write now accepts an optional keyword 'stream'.
1214 This keyword, when provided, will direct the output to either
1215 stdout, stderr, or GDB's logging output.
1217 ** Parameters can now be be sub-classed in Python, and in particular
1218 you may implement the get_set_doc and get_show_doc functions.
1219 This improves how Parameter set/show documentation is processed
1220 and allows for more dynamic content.
1222 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1223 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1224 have an is_valid method.
1226 ** Breakpoints can now be sub-classed in Python, and in particular
1227 you may implement a 'stop' function that is executed each time
1228 the inferior reaches that breakpoint.
1230 ** New function gdb.lookup_global_symbol looks up a global symbol.
1232 ** GDB values in Python are now callable if the value represents a
1233 function. For example, if 'some_value' represents a function that
1234 takes two integer parameters and returns a value, you can call
1235 that function like so:
1237 result = some_value (10,20)
1239 ** Module gdb.types has been added.
1240 It contains a collection of utilities for working with gdb.Types objects:
1241 get_basic_type, has_field, make_enum_dict.
1243 ** Module gdb.printing has been added.
1244 It contains utilities for writing and registering pretty-printers.
1245 New classes: PrettyPrinter, SubPrettyPrinter,
1246 RegexpCollectionPrettyPrinter.
1247 New function: register_pretty_printer.
1249 ** New commands "info pretty-printers", "enable pretty-printer" and
1250 "disable pretty-printer" have been added.
1252 ** gdb.parameter("directories") is now available.
1254 ** New function gdb.newest_frame returns the newest frame in the
1257 ** The gdb.InferiorThread class has a new "name" attribute. This
1258 holds the thread's name.
1260 ** Python Support for Inferior events.
1261 Python scripts can add observers to be notified of events
1262 occurring in the process being debugged.
1263 The following events are currently supported:
1264 - gdb.events.cont Continue event.
1265 - gdb.events.exited Inferior exited event.
1266 - gdb.events.stop Signal received, and Breakpoint hit events.
1270 ** GDB now puts template parameters in scope when debugging in an
1271 instantiation. For example, if you have:
1273 template<int X> int func (void) { return X; }
1275 then if you step into func<5>, "print X" will show "5". This
1276 feature requires proper debuginfo support from the compiler; it
1277 was added to GCC 4.5.
1279 ** The motion commands "next", "finish", "until", and "advance" now
1280 work better when exceptions are thrown. In particular, GDB will
1281 no longer lose control of the inferior; instead, the GDB will
1282 stop the inferior at the point at which the exception is caught.
1283 This functionality requires a change in the exception handling
1284 code that was introduced in GCC 4.5.
1286 * GDB now follows GCC's rules on accessing volatile objects when
1287 reading or writing target state during expression evaluation.
1288 One notable difference to prior behavior is that "print x = 0"
1289 no longer generates a read of x; the value of the assignment is
1290 now always taken directly from the value being assigned.
1292 * GDB now has some support for using labels in the program's source in
1293 linespecs. For instance, you can use "advance label" to continue
1294 execution to a label.
1296 * GDB now has support for reading and writing a new .gdb_index
1297 section. This section holds a fast index of DWARF debugging
1298 information and can be used to greatly speed up GDB startup and
1299 operation. See the documentation for `save gdb-index' for details.
1301 * The "watch" command now accepts an optional "-location" argument.
1302 When used, this causes GDB to watch the memory referred to by the
1303 expression. Such a watchpoint is never deleted due to it going out
1306 * GDB now supports thread debugging of core dumps on GNU/Linux.
1308 GDB now activates thread debugging using the libthread_db library
1309 when debugging GNU/Linux core dumps, similarly to when debugging
1310 live processes. As a result, when debugging a core dump file, GDB
1311 is now able to display pthread_t ids of threads. For example, "info
1312 threads" shows the same output as when debugging the process when it
1313 was live. In earlier releases, you'd see something like this:
1316 * 1 LWP 6780 main () at main.c:10
1318 While now you see this:
1321 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1323 It is also now possible to inspect TLS variables when debugging core
1326 When debugging a core dump generated on a machine other than the one
1327 used to run GDB, you may need to point GDB at the correct
1328 libthread_db library with the "set libthread-db-search-path"
1329 command. See the user manual for more details on this command.
1331 * When natively debugging programs on PowerPC BookE processors running
1332 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1333 which stop execution of the inferior whenever it executes an instruction
1334 at any address within the specified range. See the "PowerPC Embedded"
1335 section in the user manual for more details.
1337 * New features in the GDB remote stub, GDBserver
1339 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1340 and i686 LynxOS (version 5.x).
1342 ** GDBserver is now supported on Blackfin Linux.
1344 * New native configurations
1346 ia64 HP-UX ia64-*-hpux*
1350 Analog Devices, Inc. Blackfin Processor bfin-*
1352 * Ada task switching is now supported on sparc-elf targets when
1353 debugging a program using the Ravenscar Profile. For more information,
1354 see the "Tasking Support when using the Ravenscar Profile" section
1355 in the GDB user manual.
1357 * Guile support was removed.
1359 * New features in the GNU simulator
1361 ** The --map-info flag lists all known core mappings.
1363 ** CFI flashes may be simulated via the "cfi" device.
1365 *** Changes in GDB 7.2
1367 * Shared library support for remote targets by default
1369 When GDB is configured for a generic, non-OS specific target, like
1370 for example, --target=arm-eabi or one of the many *-*-elf targets,
1371 GDB now queries remote stubs for loaded shared libraries using the
1372 `qXfer:libraries:read' packet. Previously, shared library support
1373 was always disabled for such configurations.
1377 ** Argument Dependent Lookup (ADL)
1379 In C++ ADL lookup directs function search to the namespaces of its
1380 arguments even if the namespace has not been imported.
1390 Here the compiler will search for `foo' in the namespace of 'b'
1391 and find A::foo. GDB now supports this. This construct is commonly
1392 used in the Standard Template Library for operators.
1394 ** Improved User Defined Operator Support
1396 In addition to member operators, GDB now supports lookup of operators
1397 defined in a namespace and imported with a `using' directive, operators
1398 defined in the global scope, operators imported implicitly from an
1399 anonymous namespace, and the ADL operators mentioned in the previous
1401 GDB now also supports proper overload resolution for all the previously
1402 mentioned flavors of operators.
1404 ** static const class members
1406 Printing of static const class members that are initialized in the
1407 class definition has been fixed.
1409 * Windows Thread Information Block access.
1411 On Windows targets, GDB now supports displaying the Windows Thread
1412 Information Block (TIB) structure. This structure is visible either
1413 by using the new command `info w32 thread-information-block' or, by
1414 dereferencing the new convenience variable named `$_tlb', a
1415 thread-specific pointer to the TIB. This feature is also supported
1416 when remote debugging using GDBserver.
1418 * Static tracepoints
1420 Static tracepoints are calls in the user program into a tracing
1421 library. One such library is a port of the LTTng kernel tracer to
1422 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1423 When debugging with GDBserver, GDB now supports combining the GDB
1424 tracepoint machinery with such libraries. For example: the user can
1425 use GDB to probe a static tracepoint marker (a call from the user
1426 program into the tracing library) with the new "strace" command (see
1427 "New commands" below). This creates a "static tracepoint" in the
1428 breakpoint list, that can be manipulated with the same feature set
1429 as fast and regular tracepoints. E.g., collect registers, local and
1430 global variables, collect trace state variables, and define
1431 tracepoint conditions. In addition, the user can collect extra
1432 static tracepoint marker specific data, by collecting the new
1433 $_sdata internal variable. When analyzing the trace buffer, you can
1434 inspect $_sdata like any other variable available to GDB. For more
1435 information, see the "Tracepoints" chapter in GDB user manual. New
1436 remote packets have been defined to support static tracepoints, see
1437 the "New remote packets" section below.
1439 * Better reconstruction of tracepoints after disconnected tracing
1441 GDB will attempt to download the original source form of tracepoint
1442 definitions when starting a trace run, and then will upload these
1443 upon reconnection to the target, resulting in a more accurate
1444 reconstruction of the tracepoints that are in use on the target.
1448 You can now exercise direct control over the ways that GDB can
1449 affect your program. For instance, you can disallow the setting of
1450 breakpoints, so that the program can run continuously (assuming
1451 non-stop mode). In addition, the "observer" variable is available
1452 to switch all of the different controls; in observer mode, GDB
1453 cannot affect the target's behavior at all, which is useful for
1454 tasks like diagnosing live systems in the field.
1456 * The new convenience variable $_thread holds the number of the
1459 * New remote packets
1463 Return the address of the Windows Thread Information Block of a given thread.
1467 In response to several of the tracepoint packets, the target may now
1468 also respond with a number of intermediate `qRelocInsn' request
1469 packets before the final result packet, to have GDB handle
1470 relocating an instruction to execute at a different address. This
1471 is particularly useful for stubs that support fast tracepoints. GDB
1472 reports support for this feature in the qSupported packet.
1476 List static tracepoint markers in the target program.
1480 List static tracepoint markers at a given address in the target
1483 qXfer:statictrace:read
1485 Read the static trace data collected (by a `collect $_sdata'
1486 tracepoint action). The remote stub reports support for this packet
1487 to gdb's qSupported query.
1491 Send the current settings of GDB's permission flags.
1495 Send part of the source (textual) form of a tracepoint definition,
1496 which includes location, conditional, and action list.
1498 * The source command now accepts a -s option to force searching for the
1499 script in the source search path even if the script name specifies
1502 * New features in the GDB remote stub, GDBserver
1504 - GDBserver now support tracepoints (including fast tracepoints, and
1505 static tracepoints). The feature is currently supported by the
1506 i386-linux and amd64-linux builds. See the "Tracepoints support
1507 in gdbserver" section in the manual for more information.
1509 GDBserver JIT compiles the tracepoint's conditional agent
1510 expression bytecode into native code whenever possible for low
1511 overhead dynamic tracepoints conditionals. For such tracepoints,
1512 an expression that examines program state is evaluated when the
1513 tracepoint is reached, in order to determine whether to capture
1514 trace data. If the condition is simple and false, processing the
1515 tracepoint finishes very quickly and no data is gathered.
1517 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1518 for static tracepoints support.
1520 - GDBserver now supports x86_64 Windows 64-bit debugging.
1522 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1523 it understands register description.
1525 * The --batch flag now disables pagination and queries.
1527 * X86 general purpose registers
1529 GDB now supports reading/writing byte, word and double-word x86
1530 general purpose registers directly. This means you can use, say,
1531 $ah or $ax to refer, respectively, to the byte register AH and
1532 16-bit word register AX that are actually portions of the 32-bit
1533 register EAX or 64-bit register RAX.
1535 * The `commands' command now accepts a range of breakpoints to modify.
1536 A plain `commands' following a command that creates multiple
1537 breakpoints affects all the breakpoints set by that command. This
1538 applies to breakpoints set by `rbreak', and also applies when a
1539 single `break' command creates multiple breakpoints (e.g.,
1540 breakpoints on overloaded c++ functions).
1542 * The `rbreak' command now accepts a filename specification as part of
1543 its argument, limiting the functions selected by the regex to those
1544 in the specified file.
1546 * Support for remote debugging Windows and SymbianOS shared libraries
1547 from Unix hosts has been improved. Non Windows GDB builds now can
1548 understand target reported file names that follow MS-DOS based file
1549 system semantics, such as file names that include drive letters and
1550 use the backslash character as directory separator. This makes it
1551 possible to transparently use the "set sysroot" and "set
1552 solib-search-path" on Unix hosts to point as host copies of the
1553 target's shared libraries. See the new command "set
1554 target-file-system-kind" described below, and the "Commands to
1555 specify files" section in the user manual for more information.
1559 eval template, expressions...
1560 Convert the values of one or more expressions under the control
1561 of the string template to a command line, and call it.
1563 set target-file-system-kind unix|dos-based|auto
1564 show target-file-system-kind
1565 Set or show the assumed file system kind for target reported file
1568 save breakpoints <filename>
1569 Save all current breakpoint definitions to a file suitable for use
1570 in a later debugging session. To read the saved breakpoint
1571 definitions, use the `source' command.
1573 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1576 info static-tracepoint-markers
1577 Display information about static tracepoint markers in the target.
1579 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1580 Define a static tracepoint by probing a marker at the given
1581 function, line, address, or marker ID.
1585 Enable and disable observer mode.
1587 set may-write-registers on|off
1588 set may-write-memory on|off
1589 set may-insert-breakpoints on|off
1590 set may-insert-tracepoints on|off
1591 set may-insert-fast-tracepoints on|off
1592 set may-interrupt on|off
1593 Set individual permissions for GDB effects on the target. Note that
1594 some of these settings can have undesirable or surprising
1595 consequences, particularly when changed in the middle of a session.
1596 For instance, disabling the writing of memory can prevent
1597 breakpoints from being inserted, cause single-stepping to fail, or
1598 even crash your program, if you disable after breakpoints have been
1599 inserted. However, GDB should not crash.
1601 set record memory-query on|off
1602 show record memory-query
1603 Control whether to stop the inferior if memory changes caused
1604 by an instruction cannot be recorded.
1609 The disassemble command now supports "start,+length" form of two arguments.
1613 ** GDB now provides a new directory location, called the python directory,
1614 where Python scripts written for GDB can be installed. The location
1615 of that directory is <data-directory>/python, where <data-directory>
1616 is the GDB data directory. For more details, see section `Scripting
1617 GDB using Python' in the manual.
1619 ** The GDB Python API now has access to breakpoints, symbols, symbol
1620 tables, program spaces, inferiors, threads and frame's code blocks.
1621 Additionally, GDB Parameters can now be created from the API, and
1622 manipulated via set/show in the CLI.
1624 ** New functions gdb.target_charset, gdb.target_wide_charset,
1625 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1627 ** New exception gdb.GdbError.
1629 ** Pretty-printers are now also looked up in the current program space.
1631 ** Pretty-printers can now be individually enabled and disabled.
1633 ** GDB now looks for names of Python scripts to auto-load in a
1634 special section named `.debug_gdb_scripts', in addition to looking
1635 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1637 * Tracepoint actions were unified with breakpoint commands. In particular,
1638 there are no longer differences in "info break" output for breakpoints and
1639 tracepoints and the "commands" command can be used for both tracepoints and
1640 regular breakpoints.
1644 ARM Symbian arm*-*-symbianelf*
1646 * D language support.
1647 GDB now supports debugging programs written in the D programming
1650 * GDB now supports the extended ptrace interface for PowerPC which is
1651 available since Linux kernel version 2.6.34. This automatically enables
1652 any hardware breakpoints and additional hardware watchpoints available in
1653 the processor. The old ptrace interface exposes just one hardware
1654 watchpoint and no hardware breakpoints.
1656 * GDB is now able to use the Data Value Compare (DVC) register available on
1657 embedded PowerPC processors to implement in hardware simple watchpoint
1658 conditions of the form:
1660 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1662 This works in native GDB running on Linux kernels with the extended ptrace
1663 interface mentioned above.
1665 *** Changes in GDB 7.1
1669 ** Namespace Support
1671 GDB now supports importing of namespaces in C++. This enables the
1672 user to inspect variables from imported namespaces. Support for
1673 namepace aliasing has also been added. So, if a namespace is
1674 aliased in the current scope (e.g. namepace C=A; ) the user can
1675 print variables using the alias (e.g. (gdb) print C::x).
1679 All known bugs relating to the printing of virtual base class were
1680 fixed. It is now possible to call overloaded static methods using a
1685 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1686 and reinterpret_cast<> are now handled by the C++ expression parser.
1690 Xilinx MicroBlaze microblaze-*-*
1695 Xilinx MicroBlaze microblaze
1698 * Multi-program debugging.
1700 GDB now has support for multi-program (a.k.a. multi-executable or
1701 multi-exec) debugging. This allows for debugging multiple inferiors
1702 simultaneously each running a different program under the same GDB
1703 session. See "Debugging Multiple Inferiors and Programs" in the
1704 manual for more information. This implied some user visible changes
1705 in the multi-inferior support. For example, "info inferiors" now
1706 lists inferiors that are not running yet or that have exited
1707 already. See also "New commands" and "New options" below.
1709 * New tracing features
1711 GDB's tracepoint facility now includes several new features:
1713 ** Trace state variables
1715 GDB tracepoints now include support for trace state variables, which
1716 are variables managed by the target agent during a tracing
1717 experiment. They are useful for tracepoints that trigger each
1718 other, so for instance one tracepoint can count hits in a variable,
1719 and then a second tracepoint has a condition that is true when the
1720 count reaches a particular value. Trace state variables share the
1721 $-syntax of GDB convenience variables, and can appear in both
1722 tracepoint actions and condition expressions. Use the "tvariable"
1723 command to create, and "info tvariables" to view; see "Trace State
1724 Variables" in the manual for more detail.
1728 GDB now includes an option for defining fast tracepoints, which
1729 targets may implement more efficiently, such as by installing a jump
1730 into the target agent rather than a trap instruction. The resulting
1731 speedup can be by two orders of magnitude or more, although the
1732 tradeoff is that some program locations on some target architectures
1733 might not allow fast tracepoint installation, for instance if the
1734 instruction to be replaced is shorter than the jump. To request a
1735 fast tracepoint, use the "ftrace" command, with syntax identical to
1736 the regular trace command.
1738 ** Disconnected tracing
1740 It is now possible to detach GDB from the target while it is running
1741 a trace experiment, then reconnect later to see how the experiment
1742 is going. In addition, a new variable disconnected-tracing lets you
1743 tell the target agent whether to continue running a trace if the
1744 connection is lost unexpectedly.
1748 GDB now has the ability to save the trace buffer into a file, and
1749 then use that file as a target, similarly to you can do with
1750 corefiles. You can select trace frames, print data that was
1751 collected in them, and use tstatus to display the state of the
1752 tracing run at the moment that it was saved. To create a trace
1753 file, use "tsave <filename>", and to use it, do "target tfile
1756 ** Circular trace buffer
1758 You can ask the target agent to handle the trace buffer as a
1759 circular buffer, discarding the oldest trace frames to make room for
1760 newer ones, by setting circular-trace-buffer to on. This feature may
1761 not be available for all target agents.
1766 The disassemble command, when invoked with two arguments, now requires
1767 the arguments to be comma-separated.
1770 The info variables command now displays variable definitions. Files
1771 which only declare a variable are not shown.
1774 The source command is now capable of sourcing Python scripts.
1775 This feature is dependent on the debugger being build with Python
1778 Related to this enhancement is also the introduction of a new command
1779 "set script-extension" (see below).
1781 * New commands (for set/show, see "New options" below)
1783 record save [<FILENAME>]
1784 Save a file (in core file format) containing the process record
1785 execution log for replay debugging at a later time.
1787 record restore <FILENAME>
1788 Restore the process record execution log that was saved at an
1789 earlier time, for replay debugging.
1791 add-inferior [-copies <N>] [-exec <FILENAME>]
1794 clone-inferior [-copies <N>] [ID]
1795 Make a new inferior ready to execute the same program another
1796 inferior has loaded.
1801 maint info program-spaces
1802 List the program spaces loaded into GDB.
1804 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1805 show remote interrupt-sequence
1806 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1807 as the sequence to the remote target in order to interrupt the execution.
1808 Ctrl-C is a default. Some system prefers BREAK which is high level of
1809 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1810 Magic SysRq g. It is BREAK signal and character 'g'.
1812 set remote interrupt-on-connect [on | off]
1813 show remote interrupt-on-connect
1814 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1815 remote target when gdb connects to it. This is needed when you debug
1818 set remotebreak [on | off]
1820 Deprecated. Use "set/show remote interrupt-sequence" instead.
1822 tvariable $NAME [ = EXP ]
1823 Create or modify a trace state variable.
1826 List trace state variables and their values.
1828 delete tvariable $NAME ...
1829 Delete one or more trace state variables.
1832 Evaluate the given expressions without collecting anything into the
1833 trace buffer. (Valid in tracepoint actions only.)
1835 ftrace FN / FILE:LINE / *ADDR
1836 Define a fast tracepoint at the given function, line, or address.
1838 * New expression syntax
1840 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1841 GDB now parses 0b101010 identically with 42.
1845 set follow-exec-mode new|same
1846 show follow-exec-mode
1847 Control whether GDB reuses the same inferior across an exec call or
1848 creates a new one. This is useful to be able to restart the old
1849 executable after the inferior having done an exec call.
1851 set default-collect EXPR, ...
1852 show default-collect
1853 Define a list of expressions to be collected at each tracepoint.
1854 This is a useful way to ensure essential items are not overlooked,
1855 such as registers or a critical global variable.
1857 set disconnected-tracing
1858 show disconnected-tracing
1859 If set to 1, the target is instructed to continue tracing if it
1860 loses its connection to GDB. If 0, the target is to stop tracing
1863 set circular-trace-buffer
1864 show circular-trace-buffer
1865 If set to on, the target is instructed to use a circular trace buffer
1866 and discard the oldest trace frames instead of stopping the trace due
1867 to a full trace buffer. If set to off, the trace stops when the buffer
1868 fills up. Some targets may not support this.
1870 set script-extension off|soft|strict
1871 show script-extension
1872 If set to "off", the debugger does not perform any script language
1873 recognition, and all sourced files are assumed to be GDB scripts.
1874 If set to "soft" (the default), files are sourced according to
1875 filename extension, falling back to GDB scripts if the first
1877 If set to "strict", files are sourced according to filename extension.
1879 set ada trust-PAD-over-XVS on|off
1880 show ada trust-PAD-over-XVS
1881 If off, activate a workaround against a bug in the debugging information
1882 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1883 the GCC sources for more information about the GNAT encoding and
1884 PAD types in particular). It is always safe to set this option to
1885 off, but this introduces a slight performance penalty. The default
1888 * Python API Improvements
1890 ** GDB provides the new class gdb.LazyString. This is useful in
1891 some pretty-printing cases. The new method gdb.Value.lazy_string
1892 provides a simple way to create objects of this type.
1894 ** The fields returned by gdb.Type.fields now have an
1895 `is_base_class' attribute.
1897 ** The new method gdb.Type.range returns the range of an array type.
1899 ** The new method gdb.parse_and_eval can be used to parse and
1900 evaluate an expression.
1902 * New remote packets
1905 Define a trace state variable.
1908 Get the current value of a trace state variable.
1911 Set desired tracing behavior upon disconnection.
1914 Set the trace buffer to be linear or circular.
1917 Get data about the tracepoints currently in use.
1921 Process record now works correctly with hardware watchpoints.
1923 Multiple bug fixes have been made to the mips-irix port, making it
1924 much more reliable. In particular:
1925 - Debugging threaded applications is now possible again. Previously,
1926 GDB would hang while starting the program, or while waiting for
1927 the program to stop at a breakpoint.
1928 - Attaching to a running process no longer hangs.
1929 - An error occurring while loading a core file has been fixed.
1930 - Changing the value of the PC register now works again. This fixes
1931 problems observed when using the "jump" command, or when calling
1932 a function from GDB, or even when assigning a new value to $pc.
1933 - With the "finish" and "return" commands, the return value for functions
1934 returning a small array is now correctly printed.
1935 - It is now possible to break on shared library code which gets executed
1936 during a shared library init phase (code executed while executing
1937 their .init section). Previously, the breakpoint would have no effect.
1938 - GDB is now able to backtrace through the signal handler for
1939 non-threaded programs.
1941 PIE (Position Independent Executable) programs debugging is now supported.
1942 This includes debugging execution of PIC (Position Independent Code) shared
1943 libraries although for that, it should be possible to run such libraries as an
1946 *** Changes in GDB 7.0
1948 * GDB now has an interface for JIT compilation. Applications that
1949 dynamically generate code can create symbol files in memory and register
1950 them with GDB. For users, the feature should work transparently, and
1951 for JIT developers, the interface is documented in the GDB manual in the
1952 "JIT Compilation Interface" chapter.
1954 * Tracepoints may now be conditional. The syntax is as for
1955 breakpoints; either an "if" clause appended to the "trace" command,
1956 or the "condition" command is available. GDB sends the condition to
1957 the target for evaluation using the same bytecode format as is used
1958 for tracepoint actions.
1960 * The disassemble command now supports: an optional /r modifier, print the
1961 raw instructions in hex as well as in symbolic form, and an optional /m
1962 modifier to print mixed source+assembly.
1964 * Process record and replay
1966 In a architecture environment that supports ``process record and
1967 replay'', ``process record and replay'' target can record a log of
1968 the process execution, and replay it with both forward and reverse
1971 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1972 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1973 set execution-direction {forward|reverse}, for targets that support
1976 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1977 feature is available with a native GDB running on kernel version
1980 * GDB now has support for multi-byte and wide character sets on the
1981 target. Strings whose character type is wchar_t, char16_t, or
1982 char32_t are now correctly printed. GDB supports wide- and unicode-
1983 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1984 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1985 `printf'. This feature requires iconv to work properly; if your
1986 system does not have a working iconv, GDB can use GNU libiconv. See
1987 the installation instructions for more information.
1989 * GDB now supports automatic retrieval of shared library files from
1990 remote targets. To use this feature, specify a system root that begins
1991 with the `remote:' prefix, either via the `set sysroot' command or via
1992 the `--with-sysroot' configure-time option.
1994 * "info sharedlibrary" now takes an optional regex of libraries to show,
1995 and it now reports if a shared library has no debugging information.
1997 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1998 now complete on file names.
2000 * When completing in expressions, gdb will attempt to limit
2001 completions to allowable structure or union fields, where appropriate.
2002 For instance, consider:
2004 # struct example { int f1; double f2; };
2005 # struct example variable;
2008 If the user types TAB at the end of this command line, the available
2009 completions will be "f1" and "f2".
2011 * Inlined functions are now supported. They show up in backtraces, and
2012 the "step", "next", and "finish" commands handle them automatically.
2014 * GDB now supports the token-splicing (##) and stringification (#)
2015 operators when expanding macros. It also supports variable-arity
2018 * GDB now supports inspecting extra signal information, exported by
2019 the new $_siginfo convenience variable. The feature is currently
2020 implemented on linux ARM, i386 and amd64.
2022 * GDB can now display the VFP floating point registers and NEON vector
2023 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2024 can provide these registers (requires Linux 2.6.30 or later). Remote
2025 and simulator targets may also provide them.
2027 * New remote packets
2030 Search memory for a sequence of bytes.
2033 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2034 operation over reliable transport links. Use of this packet is
2035 controlled by the `set remote noack-packet' command.
2038 Kill the process with the specified process ID. Use this in preference
2039 to `k' when multiprocess protocol extensions are supported.
2042 Obtains additional operating system information
2046 Read or write additional signal information.
2048 * Removed remote protocol undocumented extension
2050 An undocumented extension to the remote protocol's `S' stop reply
2051 packet that permited the stub to pass a process id was removed.
2052 Remote servers should use the `T' stop reply packet instead.
2054 * GDB now supports multiple function calling conventions according to the
2055 DWARF-2 DW_AT_calling_convention function attribute.
2057 * The SH target utilizes the aforementioned change to distinguish between gcc
2058 and Renesas calling convention. It also adds the new CLI commands
2059 `set/show sh calling-convention'.
2061 * GDB can now read compressed debug sections, as produced by GNU gold
2062 with the --compress-debug-sections=zlib flag.
2064 * 64-bit core files are now supported on AIX.
2066 * Thread switching is now supported on Tru64.
2068 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2069 which will be allocated using malloc later in program execution.
2071 * The qXfer:libraries:read remote procotol packet now allows passing a
2072 list of section offsets.
2074 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2075 conditions handling signals delivered during attach or thread creation
2076 have also been fixed.
2078 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2079 From the user's standpoint, all unqualified instances of True and False
2080 are treated as the standard definitions, regardless of context.
2082 * GDB now parses C++ symbol and type names more flexibly. For
2085 template<typename T> class C { };
2088 GDB will now correctly handle all of:
2090 ptype C<char const *>
2091 ptype C<char const*>
2092 ptype C<const char *>
2093 ptype C<const char*>
2095 * New features in the GDB remote stub, gdbserver
2097 - The "--wrapper" command-line argument tells gdbserver to use a
2098 wrapper program to launch programs for debugging.
2100 - On PowerPC and S/390 targets, it is now possible to use a single
2101 gdbserver executable to debug both 32-bit and 64-bit programs.
2102 (This requires gdbserver itself to be built as a 64-bit executable.)
2104 - gdbserver uses the new noack protocol mode for TCP connections to
2105 reduce communications latency, if also supported and enabled in GDB.
2107 - Support for the sparc64-linux-gnu target is now included in
2110 - The amd64-linux build of gdbserver now supports debugging both
2111 32-bit and 64-bit programs.
2113 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2114 now support hardware watchpoints, and will use them automatically
2119 GDB now has support for scripting using Python. Whether this is
2120 available is determined at configure time.
2122 New GDB commands can now be written in Python.
2124 * Ada tasking support
2126 Ada tasks can now be inspected in GDB. The following commands have
2130 Print the list of Ada tasks.
2132 Print detailed information about task number N.
2134 Print the task number of the current task.
2136 Switch the context of debugging to task number N.
2138 * Support for user-defined prefixed commands. The "define" command can
2139 add new commands to existing prefixes, e.g. "target".
2141 * Multi-inferior, multi-process debugging.
2143 GDB now has generalized support for multi-inferior debugging. See
2144 "Debugging Multiple Inferiors" in the manual for more information.
2145 Although availability still depends on target support, the command
2146 set is more uniform now. The GNU/Linux specific multi-forks support
2147 has been migrated to this new framework. This implied some user
2148 visible changes; see "New commands" and also "Removed commands"
2151 * Target descriptions can now describe the target OS ABI. See the
2152 "Target Description Format" section in the user manual for more
2155 * Target descriptions can now describe "compatible" architectures
2156 to indicate that the target can execute applications for a different
2157 architecture in addition to those for the main target architecture.
2158 See the "Target Description Format" section in the user manual for
2161 * Multi-architecture debugging.
2163 GDB now includes general supports for debugging applications on
2164 hybrid systems that use more than one single processor architecture
2165 at the same time. Each such hybrid architecture still requires
2166 specific support to be added. The only hybrid architecture supported
2167 in this version of GDB is the Cell Broadband Engine.
2169 * GDB now supports integrated debugging of Cell/B.E. applications that
2170 use both the PPU and SPU architectures. To enable support for hybrid
2171 Cell/B.E. debugging, you need to configure GDB to support both the
2172 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2173 --enable-targets configure option.
2175 * Non-stop mode debugging.
2177 For some targets, GDB now supports an optional mode of operation in
2178 which you can examine stopped threads while other threads continue
2179 to execute freely. This is referred to as non-stop mode, with the
2180 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2181 section in the user manual for more information.
2183 To be able to support remote non-stop debugging, a remote stub needs
2184 to implement the non-stop mode remote protocol extensions, as
2185 described in the "Remote Non-Stop" section of the user manual. The
2186 GDB remote stub, gdbserver, has been adjusted to support these
2187 extensions on linux targets.
2189 * New commands (for set/show, see "New options" below)
2191 catch syscall [NAME(S) | NUMBER(S)]
2192 Catch system calls. Arguments, which should be names of system
2193 calls or their numbers, mean catch only those syscalls. Without
2194 arguments, every syscall will be caught. When the inferior issues
2195 any of the specified syscalls, GDB will stop and announce the system
2196 call, both when it is called and when its call returns. This
2197 feature is currently available with a native GDB running on the
2198 Linux Kernel, under the following architectures: x86, x86_64,
2199 PowerPC and PowerPC64.
2201 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2203 Search memory for a sequence of bytes.
2205 maint set python print-stack
2206 maint show python print-stack
2207 Show a stack trace when an error is encountered in a Python script.
2210 Invoke CODE by passing it to the Python interpreter.
2215 These allow macros to be defined, undefined, and listed
2219 Show operating system information about processes.
2222 List the inferiors currently under GDB's control.
2225 Switch focus to inferior number NUM.
2228 Detach from inferior number NUM.
2231 Kill inferior number NUM.
2235 set spu stop-on-load
2236 show spu stop-on-load
2237 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2239 set spu auto-flush-cache
2240 show spu auto-flush-cache
2241 Control whether to automatically flush the software-managed cache
2242 during Cell/B.E. debugging.
2244 set sh calling-convention
2245 show sh calling-convention
2246 Control the calling convention used when calling SH target functions.
2249 show debug timestamp
2250 Control display of timestamps with GDB debugging output.
2252 set disassemble-next-line
2253 show disassemble-next-line
2254 Control display of disassembled source lines or instructions when
2257 set remote noack-packet
2258 show remote noack-packet
2259 Set/show the use of remote protocol QStartNoAckMode packet. See above
2260 under "New remote packets."
2262 set remote query-attached-packet
2263 show remote query-attached-packet
2264 Control use of remote protocol `qAttached' (query-attached) packet.
2266 set remote read-siginfo-object
2267 show remote read-siginfo-object
2268 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2271 set remote write-siginfo-object
2272 show remote write-siginfo-object
2273 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2276 set remote reverse-continue
2277 show remote reverse-continue
2278 Control use of remote protocol 'bc' (reverse-continue) packet.
2280 set remote reverse-step
2281 show remote reverse-step
2282 Control use of remote protocol 'bs' (reverse-step) packet.
2284 set displaced-stepping
2285 show displaced-stepping
2286 Control displaced stepping mode. Displaced stepping is a way to
2287 single-step over breakpoints without removing them from the debuggee.
2288 Also known as "out-of-line single-stepping".
2291 show debug displaced
2292 Control display of debugging info for displaced stepping.
2294 maint set internal-error
2295 maint show internal-error
2296 Control what GDB does when an internal error is detected.
2298 maint set internal-warning
2299 maint show internal-warning
2300 Control what GDB does when an internal warning is detected.
2305 Use a wrapper program to launch programs for debugging.
2307 set multiple-symbols (all|ask|cancel)
2308 show multiple-symbols
2309 The value of this variable can be changed to adjust the debugger behavior
2310 when an expression or a breakpoint location contains an ambiguous symbol
2311 name (an overloaded function name, for instance).
2313 set breakpoint always-inserted
2314 show breakpoint always-inserted
2315 Keep breakpoints always inserted in the target, as opposed to inserting
2316 them when resuming the target, and removing them when the target stops.
2317 This option can improve debugger performance on slow remote targets.
2319 set arm fallback-mode (arm|thumb|auto)
2320 show arm fallback-mode
2321 set arm force-mode (arm|thumb|auto)
2323 These commands control how ARM GDB determines whether instructions
2324 are ARM or Thumb. The default for both settings is auto, which uses
2325 the current CPSR value for instructions without symbols; previous
2326 versions of GDB behaved as if "set arm fallback-mode arm".
2328 set disable-randomization
2329 show disable-randomization
2330 Standalone programs run with the virtual address space randomization enabled
2331 by default on some platforms. This option keeps the addresses stable across
2332 multiple debugging sessions.
2336 Control whether other threads are stopped or not when some thread hits
2341 Requests that asynchronous execution is enabled in the target, if available.
2342 In this case, it's possible to resume target in the background, and interact
2343 with GDB while the target is running. "show target-async" displays the
2344 current state of asynchronous execution of the target.
2346 set target-wide-charset
2347 show target-wide-charset
2348 The target-wide-charset is the name of the character set that GDB
2349 uses when printing characters whose type is wchar_t.
2351 set tcp auto-retry (on|off)
2353 set tcp connect-timeout
2354 show tcp connect-timeout
2355 These commands allow GDB to retry failed TCP connections to a remote stub
2356 with a specified timeout period; this is useful if the stub is launched
2357 in parallel with GDB but may not be ready to accept connections immediately.
2359 set libthread-db-search-path
2360 show libthread-db-search-path
2361 Control list of directories which GDB will search for appropriate
2364 set schedule-multiple (on|off)
2365 show schedule-multiple
2366 Allow GDB to resume all threads of all processes or only threads of
2367 the current process.
2371 Use more aggressive caching for accesses to the stack. This improves
2372 performance of remote debugging (particularly backtraces) without
2373 affecting correctness.
2375 set interactive-mode (on|off|auto)
2376 show interactive-mode
2377 Control whether GDB runs in interactive mode (on) or not (off).
2378 When in interactive mode, GDB waits for the user to answer all
2379 queries. Otherwise, GDB does not wait and assumes the default
2380 answer. When set to auto (the default), GDB determines which
2381 mode to use based on the stdin settings.
2386 For program forks, this is replaced by the new more generic `info
2387 inferiors' command. To list checkpoints, you can still use the
2388 `info checkpoints' command, which was an alias for the `info forks'
2392 Replaced by the new `inferior' command. To switch between
2393 checkpoints, you can still use the `restart' command, which was an
2394 alias for the `fork' command.
2397 This is removed, since some targets don't have a notion of
2398 processes. To switch between processes, you can still use the
2399 `inferior' command using GDB's own inferior number.
2402 For program forks, this is replaced by the new more generic `kill
2403 inferior' command. To delete a checkpoint, you can still use the
2404 `delete checkpoint' command, which was an alias for the `delete
2408 For program forks, this is replaced by the new more generic `detach
2409 inferior' command. To detach a checkpoint, you can still use the
2410 `detach checkpoint' command, which was an alias for the `detach
2413 * New native configurations
2415 x86/x86_64 Darwin i[34567]86-*-darwin*
2417 x86_64 MinGW x86_64-*-mingw*
2421 Lattice Mico32 lm32-*
2422 x86 DICOS i[34567]86-*-dicos*
2423 x86_64 DICOS x86_64-*-dicos*
2426 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2427 (mingw32ce) debugging.
2433 These commands were actually not implemented on any target.
2435 *** Changes in GDB 6.8
2437 * New native configurations
2439 NetBSD/hppa hppa*-*netbsd*
2440 Xtensa GNU/Linux xtensa*-*-linux*
2444 NetBSD/hppa hppa*-*-netbsd*
2445 Xtensa GNU/Lunux xtensa*-*-linux*
2447 * Change in command line behavior -- corefiles vs. process ids.
2449 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2450 attaching to process NUMBER fails, GDB no longer attempts to open a
2451 core file named NUMBER. Attaching to a program using the -c option
2452 is no longer supported. Instead, use the '-p' or '--pid' options.
2454 * GDB can now be built as a native debugger for debugging Windows x86
2455 (mingw32) Portable Executable (PE) programs.
2457 * Pending breakpoints no longer change their number when their address
2460 * GDB now supports breakpoints with multiple locations,
2461 including breakpoints on C++ constructors, inside C++ templates,
2462 and in inlined functions.
2464 * GDB's ability to debug optimized code has been improved. GDB more
2465 accurately identifies function bodies and lexical blocks that occupy
2466 more than one contiguous range of addresses.
2468 * Target descriptions can now describe registers for PowerPC.
2470 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2471 registers on PowerPC targets.
2473 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2474 targets even when the libthread_db library is not available.
2476 * The GDB remote stub, gdbserver, now supports the new file transfer
2477 commands (remote put, remote get, and remote delete).
2479 * The GDB remote stub, gdbserver, now supports run and attach in
2480 extended-remote mode.
2482 * hppa*64*-*-hpux11* target broken
2483 The debugger is unable to start a program and fails with the following
2484 error: "Error trying to get information about dynamic linker".
2485 The gdb-6.7 release is also affected.
2487 * GDB now supports the --enable-targets= configure option to allow
2488 building a single GDB executable that supports multiple remote
2489 target architectures.
2491 * GDB now supports debugging C and C++ programs which use the
2492 Decimal Floating Point extension. In addition, the PowerPC target
2493 now has a set of pseudo-registers to inspect decimal float values
2494 stored in two consecutive float registers.
2496 * The -break-insert MI command can optionally create pending
2499 * Improved support for debugging Ada
2500 Many improvements to the Ada language support have been made. These
2502 - Better support for Ada2005 interface types
2503 - Improved handling of arrays and slices in general
2504 - Better support for Taft-amendment types
2505 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2507 - Improved command completion in Ada
2510 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2515 set print frame-arguments (all|scalars|none)
2516 show print frame-arguments
2517 The value of this variable can be changed to control which argument
2518 values should be printed by the debugger when displaying a frame.
2523 Transfer files to and from a remote target, and delete remote files.
2530 Transfer files to and from a remote target, and delete remote files.
2532 * New remote packets
2539 Open, close, read, write, and delete files on the remote system.
2542 Attach to an existing process on the remote system, in extended-remote
2546 Run a new process on the remote system, in extended-remote mode.
2548 *** Changes in GDB 6.7
2550 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2551 bfd, libiberty and opcodes, as revealed by static analysis donated by
2552 Coverity, Inc. (http://scan.coverity.com).
2554 * When looking up multiply-defined global symbols, GDB will now prefer the
2555 symbol definition in the current shared library if it was built using the
2556 -Bsymbolic linker option.
2558 * When the Text User Interface (TUI) is not configured, GDB will now
2559 recognize the -tui command-line option and print a message that the TUI
2562 * The GDB remote stub, gdbserver, now has lower overhead for high
2563 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2565 * GDB for MIPS targets now autodetects whether a remote target provides
2566 32-bit or 64-bit register values.
2568 * Support for C++ member pointers has been improved.
2570 * GDB now understands XML target descriptions, which specify the
2571 target's overall architecture. GDB can read a description from
2572 a local file or over the remote serial protocol.
2574 * Vectors of single-byte data use a new integer type which is not
2575 automatically displayed as character or string data.
2577 * The /s format now works with the print command. It displays
2578 arrays of single-byte integers and pointers to single-byte integers
2581 * Target descriptions can now describe target-specific registers,
2582 for architectures which have implemented the support (currently
2583 only ARM, M68K, and MIPS).
2585 * GDB and the GDB remote stub, gdbserver, now support the XScale
2588 * The GDB remote stub, gdbserver, has been updated to support
2589 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2590 has been rewritten to use the standard GDB remote protocol.
2592 * GDB can now step into C++ functions which are called through thunks.
2594 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2596 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2597 layout. It also supports a TextSeg= and DataSeg= response when only
2598 segment base addresses (rather than offsets) are available.
2600 * The /i format now outputs any trailing branch delay slot instructions
2601 immediately following the last instruction within the count specified.
2603 * The GDB remote protocol "T" stop reply packet now supports a
2604 "library" response. Combined with the new "qXfer:libraries:read"
2605 packet, this response allows GDB to debug shared libraries on targets
2606 where the operating system manages the list of loaded libraries (e.g.
2607 Windows and SymbianOS).
2609 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2610 (DLLs) on Windows and Windows CE targets.
2612 * GDB now supports a faster verification that a .debug file matches its binary
2613 according to its build-id signature, if the signature is present.
2619 Enable or disable hardware flow control (RTS/CTS) on the serial port
2620 when debugging using remote targets.
2622 set mem inaccessible-by-default
2623 show mem inaccessible-by-default
2624 If the target supplies a memory map, for instance via the remote
2625 protocol's "qXfer:memory-map:read" packet, setting this variable
2626 prevents GDB from accessing memory outside the memory map. This
2627 is useful for targets with memory mapped registers or which react
2628 badly to accesses of unmapped address space.
2630 set breakpoint auto-hw
2631 show breakpoint auto-hw
2632 If the target supplies a memory map, for instance via the remote
2633 protocol's "qXfer:memory-map:read" packet, setting this variable
2634 lets GDB use hardware breakpoints automatically for memory regions
2635 where it can not use software breakpoints. This covers both the
2636 "break" command and internal breakpoints used for other commands
2637 including "next" and "finish".
2640 catch exception unhandled
2641 Stop the program execution when Ada exceptions are raised.
2644 Stop the program execution when an Ada assertion failed.
2648 Set an alternate system root for target files. This is a more
2649 general version of "set solib-absolute-prefix", which is now
2650 an alias to "set sysroot".
2653 Provide extended SPU facility status information. This set of
2654 commands is available only when debugging the Cell/B.E. SPU
2657 * New native configurations
2659 OpenBSD/sh sh*-*openbsd*
2662 unset tdesc filename
2664 Use the specified local file as an XML target description, and do
2665 not query the target for its built-in description.
2669 OpenBSD/sh sh*-*-openbsd*
2670 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2671 Toshiba Media Processor mep-elf
2673 * New remote packets
2676 Ignore the specified signals; pass them directly to the debugged program
2677 without stopping other threads or reporting them to GDB.
2679 qXfer:features:read:
2680 Read an XML target description from the target, which describes its
2685 Read or write contents of an spufs file on the target system. These
2686 packets are available only on the Cell/B.E. SPU architecture.
2688 qXfer:libraries:read:
2689 Report the loaded shared libraries. Combined with new "T" packet
2690 response, this packet allows GDB to debug shared libraries on
2691 targets where the operating system manages the list of loaded
2692 libraries (e.g. Windows and SymbianOS).
2696 Support for these obsolete configurations has been removed.
2704 i[34567]86-*-lynxos*
2705 i[34567]86-*-netware*
2706 i[34567]86-*-sco3.2v5*
2707 i[34567]86-*-sco3.2v4*
2709 i[34567]86-*-sysv4.2*
2712 i[34567]86-*-unixware2*
2713 i[34567]86-*-unixware*
2722 * Other removed features
2729 Various m68k-only ROM monitors.
2736 Various Renesas ROM monitors and debugging interfaces for SH and
2741 Support for a Macraigor serial interface to on-chip debugging.
2742 GDB does not directly support the newer parallel or USB
2747 A debug information format. The predecessor to DWARF 2 and
2748 DWARF 3, which are still supported.
2750 Support for the HP aCC compiler on HP-UX/PA-RISC
2752 SOM-encapsulated symbolic debugging information, automatic
2753 invocation of pxdb, and the aCC custom C++ ABI. This does not
2754 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2755 with aCC can still be debugged on an assembly level.
2757 MIPS ".pdr" sections
2759 A MIPS-specific format used to describe stack frame layout
2760 in debugging information.
2764 GDB could work with an older version of Guile to debug
2765 the interpreter and Scheme programs running in it.
2767 set mips stack-arg-size
2768 set mips saved-gpreg-size
2770 Use "set mips abi" to control parameter passing for MIPS.
2772 *** Changes in GDB 6.6
2777 Cell Broadband Engine SPU spu-elf
2779 * GDB can now be configured as a cross-debugger targeting native Windows
2780 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2781 running on a Windows system over TCP/IP to debug Windows programs.
2783 * The GDB remote stub, gdbserver, has been updated to support Windows and
2784 Cygwin debugging. Both single-threaded and multi-threaded programs are
2787 * The "set trust-readonly-sections" command works again. This command was
2788 broken in GDB 6.3, 6.4, and 6.5.
2790 * The "load" command now supports writing to flash memory, if the remote
2791 stub provides the required support.
2793 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2794 longer requires symbolic debug information (e.g. DWARF-2).
2799 unset substitute-path
2800 show substitute-path
2801 Manage a list of substitution rules that GDB uses to rewrite the name
2802 of the directories where the sources are located. This can be useful
2803 for instance when the sources were moved to a different location
2804 between compilation and debugging.
2808 Print each CLI command as it is executed. Each command is prefixed with
2809 a number of `+' symbols representing the nesting depth.
2810 The source command now has a `-v' option to enable the same feature.
2814 The ARM Demon monitor support (RDP protocol, "target rdp").
2816 Kernel Object Display, an embedded debugging feature which only worked with
2817 an obsolete version of Cisco IOS.
2819 The 'set download-write-size' and 'show download-write-size' commands.
2821 * New remote packets
2824 Tell a stub about GDB client features, and request remote target features.
2825 The first feature implemented is PacketSize, which allows the target to
2826 specify the size of packets it can handle - to minimize the number of
2827 packets required and improve performance when connected to a remote
2831 Fetch an OS auxilliary vector from the remote stub. This packet is a
2832 more efficient replacement for qPart:auxv:read.
2834 qXfer:memory-map:read:
2835 Fetch a memory map from the remote stub, including information about
2836 RAM, ROM, and flash memory devices.
2841 Erase and program a flash memory device.
2843 * Removed remote packets
2846 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2847 used it, and only gdbserver implemented it.
2849 *** Changes in GDB 6.5
2853 Renesas M32C/M16C m32c-elf
2855 Morpho Technologies ms1 ms1-elf
2859 init-if-undefined Initialize a convenience variable, but
2860 only if it doesn't already have a value.
2862 The following commands are presently only implemented for native GNU/Linux:
2864 checkpoint Save a snapshot of the program state.
2866 restart <n> Return the program state to a
2867 previously saved state.
2869 info checkpoints List currently saved checkpoints.
2871 delete-checkpoint <n> Delete a previously saved checkpoint.
2873 set|show detach-on-fork Tell gdb whether to detach from a newly
2874 forked process, or to keep debugging it.
2876 info forks List forks of the user program that
2877 are available to be debugged.
2879 fork <n> Switch to debugging one of several
2880 forks of the user program that are
2881 available to be debugged.
2883 delete-fork <n> Delete a fork from the list of forks
2884 that are available to be debugged (and
2885 kill the forked process).
2887 detach-fork <n> Delete a fork from the list of forks
2888 that are available to be debugged (and
2889 allow the process to continue).
2893 Morpho Technologies ms2 ms1-elf
2895 * Improved Windows host support
2897 GDB now builds as a cross debugger hosted on i686-mingw32, including
2898 native console support, and remote communications using either
2899 network sockets or serial ports.
2901 * Improved Modula-2 language support
2903 GDB can now print most types in the Modula-2 syntax. This includes:
2904 basic types, set types, record types, enumerated types, range types,
2905 pointer types and ARRAY types. Procedure var parameters are correctly
2906 printed and hexadecimal addresses and character constants are also
2907 written in the Modula-2 syntax. Best results can be obtained by using
2908 GNU Modula-2 together with the -gdwarf-2 command line option.
2912 The ARM rdi-share module.
2914 The Netware NLM debug server.
2916 *** Changes in GDB 6.4
2918 * New native configurations
2920 OpenBSD/arm arm*-*-openbsd*
2921 OpenBSD/mips64 mips64-*-openbsd*
2925 Morpho Technologies ms1 ms1-elf
2927 * New command line options
2929 --batch-silent As for --batch, but totally silent.
2930 --return-child-result The debugger will exist with the same value
2931 the child (debugged) program exited with.
2932 --eval-command COMMAND, -ex COMMAND
2933 Execute a single GDB CLI command. This may be
2934 specified multiple times and in conjunction
2935 with the --command (-x) option.
2937 * Deprecated commands removed
2939 The following commands, that were deprecated in 2000, have been
2943 set|show arm disassembly-flavor set|show arm disassembler
2944 othernames set arm disassembler
2945 set|show remotedebug set|show debug remote
2946 set|show archdebug set|show debug arch
2947 set|show eventdebug set|show debug event
2950 * New BSD user-level threads support
2952 It is now possible to debug programs using the user-level threads
2953 library on OpenBSD and FreeBSD. Currently supported (target)
2956 FreeBSD/amd64 x86_64-*-freebsd*
2957 FreeBSD/i386 i386-*-freebsd*
2958 OpenBSD/i386 i386-*-openbsd*
2960 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2961 are not yet supported.
2963 * New support for Matsushita MN10300 w/sim added
2964 (Work in progress). mn10300-elf.
2966 * REMOVED configurations and files
2968 VxWorks and the XDR protocol *-*-vxworks
2969 Motorola MCORE mcore-*-*
2970 National Semiconductor NS32000 ns32k-*-*
2972 * New "set print array-indexes" command
2974 After turning this setting "on", GDB prints the index of each element
2975 when displaying arrays. The default is "off" to preserve the previous
2978 * VAX floating point support
2980 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2982 * User-defined command support
2984 In addition to using $arg0..$arg9 for argument passing, it is now possible
2985 to use $argc to determine now many arguments have been passed. See the
2986 section on user-defined commands in the user manual for more information.
2988 *** Changes in GDB 6.3:
2990 * New command line option
2992 GDB now accepts -l followed by a number to set the timeout for remote
2995 * GDB works with GCC -feliminate-dwarf2-dups
2997 GDB now supports a more compact representation of DWARF-2 debug
2998 information using DW_FORM_ref_addr references. These are produced
2999 by GCC with the option -feliminate-dwarf2-dups and also by some
3000 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3001 to use -feliminate-dwarf2-dups.
3003 * Internationalization
3005 When supported by the host system, GDB will be built with
3006 internationalization (libintl). The task of marking up the sources is
3007 continued, we're looking forward to our first translation.
3011 Initial support for debugging programs compiled with the GNAT
3012 implementation of the Ada programming language has been integrated
3013 into GDB. In this release, support is limited to expression evaluation.
3015 * New native configurations
3017 GNU/Linux/m32r m32r-*-linux-gnu
3021 GDB's remote protocol now includes support for the 'p' packet. This
3022 packet is used to fetch individual registers from a remote inferior.
3024 * END-OF-LIFE registers[] compatibility module
3026 GDB's internal register infrastructure has been completely rewritten.
3027 The new infrastructure making possible the implementation of key new
3028 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3031 GDB 6.3 will be the last release to include the the registers[]
3032 compatibility module that allowed out-of-date configurations to
3033 continue to work. This change directly impacts the following
3043 powerpc bdm protocol
3045 Unless there is activity to revive these configurations, they will be
3046 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3048 * OBSOLETE configurations and files
3050 Configurations that have been declared obsolete in this release have
3051 been commented out. Unless there is activity to revive these
3052 configurations, the next release of GDB will have their sources
3053 permanently REMOVED.
3062 *** Changes in GDB 6.2.1:
3064 * MIPS `break main; run' gave an heuristic-fence-post warning
3066 When attempting to run even a simple program, a warning about
3067 heuristic-fence-post being hit would be reported. This problem has
3070 * MIPS IRIX 'long double' crashed GDB
3072 When examining a long double variable, GDB would get a segmentation
3073 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3074 IRIX long double values).
3078 A bug in the VAX stack code was causing problems with the "next"
3079 command. This problem has been fixed.
3081 *** Changes in GDB 6.2:
3083 * Fix for ``many threads''
3085 On GNU/Linux systems that use the NPTL threads library, a program
3086 rapidly creating and deleting threads would confuse GDB leading to the
3089 ptrace: No such process.
3090 thread_db_get_info: cannot get thread info: generic error
3092 This problem has been fixed.
3094 * "-async" and "-noasync" options removed.
3096 Support for the broken "-noasync" option has been removed (it caused
3099 * New ``start'' command.
3101 This command runs the program until the begining of the main procedure.
3103 * New BSD Kernel Data Access Library (libkvm) interface
3105 Using ``target kvm'' it is now possible to debug kernel core dumps and
3106 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3107 platforms. Currently supported (native-only) configurations are:
3109 FreeBSD/amd64 x86_64-*-freebsd*
3110 FreeBSD/i386 i?86-*-freebsd*
3111 NetBSD/i386 i?86-*-netbsd*
3112 NetBSD/m68k m68*-*-netbsd*
3113 NetBSD/sparc sparc-*-netbsd*
3114 OpenBSD/amd64 x86_64-*-openbsd*
3115 OpenBSD/i386 i?86-*-openbsd*
3116 OpenBSD/m68k m68*-openbsd*
3117 OpenBSD/sparc sparc-*-openbsd*
3119 * Signal trampoline code overhauled
3121 Many generic problems with GDB's signal handling code have been fixed.
3122 These include: backtraces through non-contiguous stacks; recognition
3123 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3124 call; backtrace through a signal trampoline; step into and out of
3125 signal handlers; and single-stepping in the signal trampoline.
3127 Please note that kernel bugs are a limiting factor here. These
3128 features have been shown to work on an s390 GNU/Linux system that
3129 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3131 * Cygwin support for DWARF 2 added.
3133 * New native configurations
3135 GNU/Linux/hppa hppa*-*-linux*
3136 OpenBSD/hppa hppa*-*-openbsd*
3137 OpenBSD/m68k m68*-*-openbsd*
3138 OpenBSD/m88k m88*-*-openbsd*
3139 OpenBSD/powerpc powerpc-*-openbsd*
3140 NetBSD/vax vax-*-netbsd*
3141 OpenBSD/vax vax-*-openbsd*
3143 * END-OF-LIFE frame compatibility module
3145 GDB's internal frame infrastructure has been completely rewritten.
3146 The new infrastructure making it possible to support key new features
3147 including DWARF 2 Call Frame Information. To aid in the task of
3148 migrating old configurations to this new infrastructure, a
3149 compatibility module, that allowed old configurations to continue to
3150 work, was also included.
3152 GDB 6.2 will be the last release to include this frame compatibility
3153 module. This change directly impacts the following configurations:
3163 Unless there is activity to revive these configurations, they will be
3164 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3166 * REMOVED configurations and files
3168 Sun 3, running SunOS 3 m68*-*-sunos3*
3169 Sun 3, running SunOS 4 m68*-*-sunos4*
3170 Sun 2, running SunOS 3 m68000-*-sunos3*
3171 Sun 2, running SunOS 4 m68000-*-sunos4*
3172 Motorola 680x0 running LynxOS m68*-*-lynxos*
3173 AT&T 3b1/Unix pc m68*-att-*
3174 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3175 decstation mips-dec-* mips-little-*
3176 riscos mips-*-riscos* mips-*-sysv*
3177 sonymips mips-sony-*
3178 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3180 *** Changes in GDB 6.1.1:
3182 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3184 The TUI (Text-mode User Interface) is now built as part of a default
3185 GDB configuration. It is enabled by either selecting the TUI with the
3186 command line option "-i=tui" or by running the separate "gdbtui"
3187 program. For more information on the TUI, see the manual "Debugging
3190 * Pending breakpoint support (also included in GDB 6.1)
3192 Support has been added to allow you to specify breakpoints in shared
3193 libraries that have not yet been loaded. If a breakpoint location
3194 cannot be found, and the "breakpoint pending" option is set to auto,
3195 GDB queries you if you wish to make the breakpoint pending on a future
3196 shared-library load. If and when GDB resolves the breakpoint symbol,
3197 the pending breakpoint is removed as one or more regular breakpoints
3200 Pending breakpoints are very useful for GCJ Java debugging.
3202 * Fixed ISO-C build problems
3204 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3205 non ISO-C code that stopped them being built using a more strict ISO-C
3206 compiler (e.g., IBM's C compiler).
3208 * Fixed build problem on IRIX 5
3210 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3211 wasn't able to compile compile on an IRIX 5 system.
3213 * Added execute permission to gdb/gdbserver/configure
3215 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3216 permission. This bug would cause configure to fail on a number of
3217 systems (Solaris, IRIX). Ref: server/519.
3219 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3221 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3222 has been updated to use constant array sizes.
3224 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3226 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3227 its generated DWARF Call Frame Info. This encoding was causing GDB to
3228 panic, that panic has been fixed. Ref: gdb/1628.
3230 * Fixed a problem when examining parameters in shared library code.
3232 When examining parameters in optimized shared library code generated
3233 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3234 not available''. GDB now correctly displays the variable's value.
3236 *** Changes in GDB 6.1:
3238 * Removed --with-mmalloc
3240 Support for the mmalloc memory manager has been removed, as it
3241 conflicted with the internal gdb byte cache.
3243 * Changes in AMD64 configurations
3245 The AMD64 target now includes the %cs and %ss registers. As a result
3246 the AMD64 remote protocol has changed; this affects the floating-point
3247 and SSE registers. If you rely on those registers for your debugging,
3248 you should upgrade gdbserver on the remote side.
3250 * Revised SPARC target
3252 The SPARC target has been completely revised, incorporating the
3253 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3254 support for LynxOS and SunOS 4 has been dropped. Calling functions
3255 from within GDB on operating systems with a non-executable stack
3256 (Solaris, OpenBSD) now works.
3260 GDB has a new C++ demangler which does a better job on the mangled
3261 names generated by current versions of g++. It also runs faster, so
3262 with this and other changes gdb should now start faster on large C++
3265 * DWARF 2 Location Expressions
3267 GDB support for location expressions has been extended to support function
3268 arguments and frame bases. Older versions of GDB could crash when they
3271 * C++ nested types and namespaces
3273 GDB's support for nested types and namespaces in C++ has been
3274 improved, especially if you use the DWARF 2 debugging format. (This
3275 is the default for recent versions of GCC on most platforms.)
3276 Specifically, if you have a class "Inner" defined within a class or
3277 namespace "Outer", then GDB realizes that the class's name is
3278 "Outer::Inner", not simply "Inner". This should greatly reduce the
3279 frequency of complaints about not finding RTTI symbols. In addition,
3280 if you are stopped at inside of a function defined within a namespace,
3281 GDB modifies its name lookup accordingly.
3283 * New native configurations
3285 NetBSD/amd64 x86_64-*-netbsd*
3286 OpenBSD/amd64 x86_64-*-openbsd*
3287 OpenBSD/alpha alpha*-*-openbsd*
3288 OpenBSD/sparc sparc-*-openbsd*
3289 OpenBSD/sparc64 sparc64-*-openbsd*
3291 * New debugging protocols
3293 M32R with SDI protocol m32r-*-elf*
3295 * "set prompt-escape-char" command deleted.
3297 The command "set prompt-escape-char" has been deleted. This command,
3298 and its very obscure effet on GDB's prompt, was never documented,
3299 tested, nor mentioned in the NEWS file.
3301 * OBSOLETE configurations and files
3303 Configurations that have been declared obsolete in this release have
3304 been commented out. Unless there is activity to revive these
3305 configurations, the next release of GDB will have their sources
3306 permanently REMOVED.
3308 Sun 3, running SunOS 3 m68*-*-sunos3*
3309 Sun 3, running SunOS 4 m68*-*-sunos4*
3310 Sun 2, running SunOS 3 m68000-*-sunos3*
3311 Sun 2, running SunOS 4 m68000-*-sunos4*
3312 Motorola 680x0 running LynxOS m68*-*-lynxos*
3313 AT&T 3b1/Unix pc m68*-att-*
3314 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3315 decstation mips-dec-* mips-little-*
3316 riscos mips-*-riscos* mips-*-sysv*
3317 sonymips mips-sony-*
3318 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3320 * REMOVED configurations and files
3322 SGI Irix-4.x mips-sgi-irix4 or iris4
3323 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3324 Z8000 simulator z8k-zilog-none or z8ksim
3325 Matsushita MN10200 w/simulator mn10200-*-*
3326 H8/500 simulator h8500-hitachi-hms or h8500hms
3327 HP/PA running BSD hppa*-*-bsd*
3328 HP/PA running OSF/1 hppa*-*-osf*
3329 HP/PA Pro target hppa*-*-pro*
3330 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3331 386BSD i[3456]86-*-bsd*
3332 Sequent family i[3456]86-sequent-sysv4*
3333 i[3456]86-sequent-sysv*
3334 i[3456]86-sequent-bsd*
3335 SPARC running LynxOS sparc-*-lynxos*
3336 SPARC running SunOS 4 sparc-*-sunos4*
3337 Tsqware Sparclet sparclet-*-*
3338 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3340 *** Changes in GDB 6.0:
3344 Support for debugging the Objective-C programming language has been
3345 integrated into GDB.
3347 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3349 DWARF 2's Call Frame Information makes available compiler generated
3350 information that more exactly describes the program's run-time stack.
3351 By using this information, GDB is able to provide more robust stack
3354 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3355 have been updated to use a new backtrace mechanism which includes
3356 DWARF 2 CFI support.
3360 GDB's remote protocol has been extended to include support for hosted
3361 file I/O (where the remote target uses GDB's file system). See GDB's
3362 remote protocol documentation for details.
3364 * All targets using the new architecture framework.
3366 All of GDB's targets have been updated to use the new internal
3367 architecture framework. The way is now open for future GDB releases
3368 to include cross-architecture native debugging support (i386 on amd64,
3371 * GNU/Linux's Thread Local Storage (TLS)
3373 GDB now includes support for for the GNU/Linux implementation of
3374 per-thread variables.
3376 * GNU/Linux's Native POSIX Thread Library (NPTL)
3378 GDB's thread code has been updated to work with either the new
3379 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3381 * Separate debug info.
3383 GDB, in conjunction with BINUTILS, now supports a mechanism for
3384 automatically loading debug information from a separate file. Instead
3385 of shipping full debug and non-debug versions of system libraries,
3386 system integrators can now instead ship just the stripped libraries
3387 and optional debug files.
3389 * DWARF 2 Location Expressions
3391 DWARF 2 Location Expressions allow the compiler to more completely
3392 describe the location of variables (even in optimized code) to the
3395 GDB now includes preliminary support for location expressions (support
3396 for DW_OP_piece is still missing).
3400 A number of long standing bugs that caused GDB to die while starting a
3401 Java application have been fixed. GDB's Java support is now
3402 considered "useable".
3404 * GNU/Linux support for fork, vfork, and exec.
3406 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3407 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3410 * GDB supports logging output to a file
3412 There are two new commands, "set logging" and "show logging", which can be
3413 used to capture GDB's output to a file.
3415 * The meaning of "detach" has changed for gdbserver
3417 The "detach" command will now resume the application, as documented. To
3418 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3421 * d10v, m68hc11 `regs' command deprecated
3423 The `info registers' command has been updated so that it displays the
3424 registers using a format identical to the old `regs' command.
3428 A new command, "maint set profile on/off", has been added. This command can
3429 be used to enable or disable profiling while running GDB, to profile a
3430 session or a set of commands. In addition there is a new configure switch,
3431 "--enable-profiling", which will cause GDB to be compiled with profiling
3432 data, for more informative profiling results.
3434 * Default MI syntax changed to "mi2".
3436 The default MI (machine interface) syntax, enabled by the command line
3437 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3438 "mi1", can be enabled by specifying the option "-i=mi1".
3440 Support for the original "mi0" syntax (included in GDB 5.0) has been
3443 Fix for gdb/192: removed extraneous space when displaying frame level.
3444 Fix for gdb/672: update changelist is now output in mi list format.
3445 Fix for gdb/702: a -var-assign that updates the value now shows up
3446 in a subsequent -var-update.
3448 * New native configurations.
3450 FreeBSD/amd64 x86_64-*-freebsd*
3452 * Multi-arched targets.
3454 HP/PA HPUX11 hppa*-*-hpux*
3455 Renesas M32R/D w/simulator m32r-*-elf*
3457 * OBSOLETE configurations and files
3459 Configurations that have been declared obsolete in this release have
3460 been commented out. Unless there is activity to revive these
3461 configurations, the next release of GDB will have their sources
3462 permanently REMOVED.
3464 Z8000 simulator z8k-zilog-none or z8ksim
3465 Matsushita MN10200 w/simulator mn10200-*-*
3466 H8/500 simulator h8500-hitachi-hms or h8500hms
3467 HP/PA running BSD hppa*-*-bsd*
3468 HP/PA running OSF/1 hppa*-*-osf*
3469 HP/PA Pro target hppa*-*-pro*
3470 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3471 Sequent family i[3456]86-sequent-sysv4*
3472 i[3456]86-sequent-sysv*
3473 i[3456]86-sequent-bsd*
3474 Tsqware Sparclet sparclet-*-*
3475 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3477 * REMOVED configurations and files
3480 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3481 IBM AIX PS/2 i[3456]86-*-aix
3482 i386 running Mach 3.0 i[3456]86-*-mach3*
3483 i386 running Mach i[3456]86-*-mach*
3484 i386 running OSF/1 i[3456]86-*osf1mk*
3485 HP/Apollo 68k Family m68*-apollo*-sysv*,
3487 m68*-hp-bsd*, m68*-hp-hpux*
3488 Argonaut Risc Chip (ARC) arc-*-*
3489 Mitsubishi D30V d30v-*-*
3490 Fujitsu FR30 fr30-*-elf*
3491 OS/9000 i[34]86-*-os9k
3492 I960 with MON960 i960-*-coff
3494 * MIPS $fp behavior changed
3496 The convenience variable $fp, for the MIPS, now consistently returns
3497 the address of the current frame's base. Previously, depending on the
3498 context, $fp could refer to either $sp or the current frame's base
3499 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3500 The GNU Source-Level Debugger''.
3502 *** Changes in GDB 5.3:
3504 * GNU/Linux shared library multi-threaded performance improved.
3506 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3507 `/proc', in preference to `ptrace' for memory reads. This may result
3508 in an improvement in the start-up time of multi-threaded, shared
3509 library applications when run under GDB. One GDB user writes: ``loads
3510 shared libs like mad''.
3512 * ``gdbserver'' now supports multi-threaded applications on some targets
3514 Support for debugging multi-threaded applications which use
3515 the GNU/Linux LinuxThreads package has been added for
3516 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3517 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3519 * GDB now supports C/C++ preprocessor macros.
3521 GDB now expands preprocessor macro invocations in C/C++ expressions,
3522 and provides various commands for showing macro definitions and how
3525 The new command `macro expand EXPRESSION' expands any macro
3526 invocations in expression, and shows the result.
3528 The new command `show macro MACRO-NAME' shows the definition of the
3529 macro named MACRO-NAME, and where it was defined.
3531 Most compilers don't include information about macros in the debugging
3532 information by default. In GCC 3.1, for example, you need to compile
3533 your program with the options `-gdwarf-2 -g3'. If the macro
3534 information is present in the executable, GDB will read it.
3536 * Multi-arched targets.
3538 DEC Alpha (partial) alpha*-*-*
3539 DEC VAX (partial) vax-*-*
3541 National Semiconductor NS32000 (partial) ns32k-*-*
3542 Motorola 68000 (partial) m68k-*-*
3543 Motorola MCORE mcore-*-*
3547 Fujitsu FRV architecture added by Red Hat frv*-*-*
3550 * New native configurations
3552 Alpha NetBSD alpha*-*-netbsd*
3553 SH NetBSD sh*-*-netbsdelf*
3554 MIPS NetBSD mips*-*-netbsd*
3555 UltraSPARC NetBSD sparc64-*-netbsd*
3557 * OBSOLETE configurations and files
3559 Configurations that have been declared obsolete in this release have
3560 been commented out. Unless there is activity to revive these
3561 configurations, the next release of GDB will have their sources
3562 permanently REMOVED.
3564 Mitsubishi D30V d30v-*-*
3565 OS/9000 i[34]86-*-os9k
3566 IBM AIX PS/2 i[3456]86-*-aix
3567 Fujitsu FR30 fr30-*-elf*
3568 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3569 Argonaut Risc Chip (ARC) arc-*-*
3570 i386 running Mach 3.0 i[3456]86-*-mach3*
3571 i386 running Mach i[3456]86-*-mach*
3572 i386 running OSF/1 i[3456]86-*osf1mk*
3573 HP/Apollo 68k Family m68*-apollo*-sysv*,
3575 m68*-hp-bsd*, m68*-hp-hpux*
3576 I960 with MON960 i960-*-coff
3578 * OBSOLETE languages
3580 CHILL, a Pascal like language used by telecommunications companies.
3582 * REMOVED configurations and files
3584 AMD 29k family via UDI a29k-amd-udi, udi29k
3585 A29K VxWorks a29k-*-vxworks
3586 AMD 29000 embedded, using EBMON a29k-none-none
3587 AMD 29000 embedded with COFF a29k-none-coff
3588 AMD 29000 embedded with a.out a29k-none-aout
3590 testsuite/gdb.hp/gdb.threads-hp/ directory
3592 * New command "set max-user-call-depth <nnn>"
3594 This command allows the user to limit the call depth of user-defined
3595 commands. The default is 1024.
3597 * Changes in FreeBSD/i386 native debugging.
3599 Support for the "generate-core-file" has been added.
3601 * New commands "dump", "append", and "restore".
3603 These commands allow data to be copied from target memory
3604 to a bfd-format or binary file (dump and append), and back
3605 from a file into memory (restore).
3607 * Improved "next/step" support on multi-processor Alpha Tru64.
3609 The previous single-step mechanism could cause unpredictable problems,
3610 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3611 of a software single-step mechanism prevents this.
3613 *** Changes in GDB 5.2.1:
3621 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3622 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3623 Fix, by Joel Brobecker imported from mainline.
3625 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3626 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3627 Fix, by Fred Fish, imported from mainline.
3629 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3630 Surprisingly enough, it works now.
3631 By Michal Ludvig, imported from mainline.
3633 i386 hardware watchpoint support:
3634 avoid misses on second run for some targets.
3635 By Pierre Muller, imported from mainline.
3637 *** Changes in GDB 5.2:
3639 * New command "set trust-readonly-sections on[off]".
3641 This command is a hint that tells gdb that read-only sections
3642 really are read-only (ie. that their contents will not change).
3643 In this mode, gdb will go to the object file rather than the
3644 target to read memory from read-only sections (such as ".text").
3645 This can be a significant performance improvement on some
3646 (notably embedded) targets.
3648 * New command "generate-core-file" (or "gcore").
3650 This new gdb command allows the user to drop a core file of the child
3651 process state at any time. So far it's been implemented only for
3652 GNU/Linux and Solaris, but should be relatively easily ported to other
3653 hosts. Argument is core file name (defaults to core.<pid>).
3655 * New command line option
3657 GDB now accepts --pid or -p followed by a process id.
3659 * Change in command line behavior -- corefiles vs. process ids.
3661 There is a subtle behavior in the way in which GDB handles
3662 command line arguments. The first non-flag argument is always
3663 a program to debug, but the second non-flag argument may either
3664 be a corefile or a process id. Previously, GDB would attempt to
3665 open the second argument as a corefile, and if that failed, would
3666 issue a superfluous error message and then attempt to attach it as
3667 a process. Now, if the second argument begins with a non-digit,
3668 it will be treated as a corefile. If it begins with a digit,
3669 GDB will attempt to attach it as a process, and if no such process
3670 is found, will then attempt to open it as a corefile.
3672 * Changes in ARM configurations.
3674 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3675 configuration is fully multi-arch.
3677 * New native configurations
3679 ARM NetBSD arm*-*-netbsd*
3680 x86 OpenBSD i[3456]86-*-openbsd*
3681 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3682 Sparc64 running FreeBSD sparc64-*-freebsd*
3686 Sanyo XStormy16 xstormy16-elf
3688 * OBSOLETE configurations and files
3690 Configurations that have been declared obsolete in this release have
3691 been commented out. Unless there is activity to revive these
3692 configurations, the next release of GDB will have their sources
3693 permanently REMOVED.
3695 AMD 29k family via UDI a29k-amd-udi, udi29k
3696 A29K VxWorks a29k-*-vxworks
3697 AMD 29000 embedded, using EBMON a29k-none-none
3698 AMD 29000 embedded with COFF a29k-none-coff
3699 AMD 29000 embedded with a.out a29k-none-aout
3701 testsuite/gdb.hp/gdb.threads-hp/ directory
3703 * REMOVED configurations and files
3705 TI TMS320C80 tic80-*-*
3707 PowerPC Solaris powerpcle-*-solaris*
3708 PowerPC Windows NT powerpcle-*-cygwin32
3709 PowerPC Netware powerpc-*-netware*
3710 Harris/CXUX m88k m88*-harris-cxux*
3711 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3712 ns32k-utek-sysv* ns32k-utek-*
3713 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3714 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3715 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3716 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3717 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3719 * Changes to command line processing
3721 The new `--args' feature can be used to specify command-line arguments
3722 for the inferior from gdb's command line.
3724 * Changes to key bindings
3726 There is a new `operate-and-get-next' function bound to `C-o'.
3728 *** Changes in GDB 5.1.1
3730 Fix compile problem on DJGPP.
3732 Fix a problem with floating-point registers on the i386 being
3735 Fix to stop GDB crashing on .debug_str debug info.
3737 Numerous documentation fixes.
3739 Numerous testsuite fixes.
3741 *** Changes in GDB 5.1:
3743 * New native configurations
3745 Alpha FreeBSD alpha*-*-freebsd*
3746 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3747 MIPS GNU/Linux mips*-*-linux*
3748 MIPS SGI Irix 6.x mips*-sgi-irix6*
3749 ia64 AIX ia64-*-aix*
3750 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3754 Motorola 68HC11 and 68HC12 m68hc11-elf
3756 UltraSparc running GNU/Linux sparc64-*-linux*
3758 * OBSOLETE configurations and files
3760 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3761 Harris/CXUX m88k m88*-harris-cxux*
3762 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3763 ns32k-utek-sysv* ns32k-utek-*
3764 TI TMS320C80 tic80-*-*
3766 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3767 PowerPC Solaris powerpcle-*-solaris*
3768 PowerPC Windows NT powerpcle-*-cygwin32
3769 PowerPC Netware powerpc-*-netware*
3770 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3771 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3772 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3773 Apple Macintosh (MPW) host N/A
3775 stuff.c (Program to stuff files into a specially prepared space in kdb)
3776 kdb-start.c (Main loop for the standalone kernel debugger)
3778 Configurations that have been declared obsolete in this release have
3779 been commented out. Unless there is activity to revive these
3780 configurations, the next release of GDB will have their sources
3781 permanently REMOVED.
3783 * REMOVED configurations and files
3785 Altos 3068 m68*-altos-*
3786 Convex c1-*-*, c2-*-*
3788 ARM RISCix arm-*-* (as host)
3792 * GDB has been converted to ISO C.
3794 GDB's source code has been converted to ISO C. In particular, the
3795 sources are fully protoized, and rely on standard headers being
3800 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3802 * The MI enabled by default.
3804 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3805 revised and enabled by default. Packages which use GDB as a debugging
3806 engine behind a UI or another front end are encouraged to switch to
3807 using the GDB/MI interface, instead of the old annotations interface
3808 which is now deprecated.
3810 * Support for debugging Pascal programs.
3812 GDB now includes support for debugging Pascal programs. The following
3813 main features are supported:
3815 - Pascal-specific data types such as sets;
3817 - automatic recognition of Pascal sources based on file-name
3820 - Pascal-style display of data types, variables, and functions;
3822 - a Pascal expression parser.
3824 However, some important features are not yet supported.
3826 - Pascal string operations are not supported at all;
3828 - there are some problems with boolean types;
3830 - Pascal type hexadecimal constants are not supported
3831 because they conflict with the internal variables format;
3833 - support for Pascal objects and classes is not full yet;
3835 - unlike Pascal, GDB is case-sensitive for symbol names.
3837 * Changes in completion.
3839 Commands such as `shell', `run' and `set args', which pass arguments
3840 to inferior programs, now complete on file names, similar to what
3841 users expect at the shell prompt.
3843 Commands which accept locations, such as `disassemble', `print',
3844 `breakpoint', `until', etc. now complete on filenames as well as
3845 program symbols. Thus, if you type "break foob TAB", and the source
3846 files linked into the programs include `foobar.c', that file name will
3847 be one of the candidates for completion. However, file names are not
3848 considered for completion after you typed a colon that delimits a file
3849 name from a name of a function in that file, as in "break foo.c:bar".
3851 `set demangle-style' completes on available demangling styles.
3853 * New platform-independent commands:
3855 It is now possible to define a post-hook for a command as well as a
3856 hook that runs before the command. For more details, see the
3857 documentation of `hookpost' in the GDB manual.
3859 * Changes in GNU/Linux native debugging.
3861 Support for debugging multi-threaded programs has been completely
3862 revised for all platforms except m68k and sparc. You can now debug as
3863 many threads as your system allows you to have.
3865 Attach/detach is supported for multi-threaded programs.
3867 Support for SSE registers was added for x86. This doesn't work for
3868 multi-threaded programs though.
3870 * Changes in MIPS configurations.
3872 Multi-arch support is enabled for all MIPS configurations.
3874 GDB can now be built as native debugger on SGI Irix 6.x systems for
3875 debugging n32 executables. (Debugging 64-bit executables is not yet
3878 * Unified support for hardware watchpoints in all x86 configurations.
3880 Most (if not all) native x86 configurations support hardware-assisted
3881 breakpoints and watchpoints in a unified manner. This support
3882 implements debug register sharing between watchpoints, which allows to
3883 put a virtually infinite number of watchpoints on the same address,
3884 and also supports watching regions up to 16 bytes with several debug
3887 The new maintenance command `maintenance show-debug-regs' toggles
3888 debugging print-outs in functions that insert, remove, and test
3889 watchpoints and hardware breakpoints.
3891 * Changes in the DJGPP native configuration.
3893 New command ``info dos sysinfo'' displays assorted information about
3894 the CPU, OS, memory, and DPMI server.
3896 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3897 display information about segment descriptors stored in GDT, LDT, and
3900 New commands ``info dos pde'' and ``info dos pte'' display entries
3901 from Page Directory and Page Tables (for now works with CWSDPMI only).
3902 New command ``info dos address-pte'' displays the Page Table entry for
3903 a given linear address.
3905 GDB can now pass command lines longer than 126 characters to the
3906 program being debugged (requires an update to the libdbg.a library
3907 which is part of the DJGPP development kit).
3909 DWARF2 debug info is now supported.
3911 It is now possible to `step' and `next' through calls to `longjmp'.
3913 * Changes in documentation.
3915 All GDB documentation was converted to GFDL, the GNU Free
3916 Documentation License.
3918 Tracepoints-related commands are now fully documented in the GDB
3921 TUI, the Text-mode User Interface, is now documented in the manual.
3923 Tracepoints-related commands are now fully documented in the GDB
3926 The "GDB Internals" manual now has an index. It also includes
3927 documentation of `ui_out' functions, GDB coding standards, x86
3928 hardware watchpoints, and memory region attributes.
3930 * GDB's version number moved to ``version.in''
3932 The Makefile variable VERSION has been replaced by the file
3933 ``version.in''. People creating GDB distributions should update the
3934 contents of this file.
3938 GUD support is now a standard part of the EMACS distribution.
3940 *** Changes in GDB 5.0:
3942 * Improved support for debugging FP programs on x86 targets
3944 Unified and much-improved support for debugging floating-point
3945 programs on all x86 targets. In particular, ``info float'' now
3946 displays the FP registers in the same format on all x86 targets, with
3947 greater level of detail.
3949 * Improvements and bugfixes in hardware-assisted watchpoints
3951 It is now possible to watch array elements, struct members, and
3952 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3953 on x86 targets no longer erroneously trigger when the address is
3956 * Improvements in the native DJGPP version of GDB
3958 The distribution now includes all the scripts and auxiliary files
3959 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3960 machines ``out of the box''.
3962 The DJGPP version can now debug programs that use signals. It is
3963 possible to catch signals that happened in the debuggee, deliver
3964 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3965 would kill the program being debugged.) Programs that hook hardware
3966 interrupts (keyboard, timer, etc.) can also be debugged.
3968 It is now possible to debug DJGPP programs that redirect their
3969 standard handles or switch them to raw (as opposed to cooked) mode, or
3970 even close them. The command ``run < foo > bar'' works as expected,
3971 and ``info terminal'' reports useful information about the debuggee's
3972 terminal, including raw/cooked mode, redirection, etc.
3974 The DJGPP version now uses termios functions for console I/O, which
3975 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3978 DOS-style file names with drive letters are now fully supported by
3981 It is now possible to debug DJGPP programs that switch their working
3982 directory. It is also possible to rerun the debuggee any number of
3983 times without restarting GDB; thus, you can use the same setup,
3984 breakpoints, etc. for many debugging sessions.
3986 * New native configurations
3988 ARM GNU/Linux arm*-*-linux*
3989 PowerPC GNU/Linux powerpc-*-linux*
3993 Motorola MCore mcore-*-*
3994 x86 VxWorks i[3456]86-*-vxworks*
3995 PowerPC VxWorks powerpc-*-vxworks*
3996 TI TMS320C80 tic80-*-*
3998 * OBSOLETE configurations
4000 Altos 3068 m68*-altos-*
4001 Convex c1-*-*, c2-*-*
4003 ARM RISCix arm-*-* (as host)
4006 Configurations that have been declared obsolete will be commented out,
4007 but the code will be left in place. If there is no activity to revive
4008 these configurations before the next release of GDB, the sources will
4009 be permanently REMOVED.
4011 * Gould support removed
4013 Support for the Gould PowerNode and NP1 has been removed.
4015 * New features for SVR4
4017 On SVR4 native platforms (such as Solaris), if you attach to a process
4018 without first loading a symbol file, GDB will now attempt to locate and
4019 load symbols from the running process's executable file.
4021 * Many C++ enhancements
4023 C++ support has been greatly improved. Overload resolution now works properly
4024 in almost all cases. RTTI support is on the way.
4026 * Remote targets can connect to a sub-program
4028 A popen(3) style serial-device has been added. This device starts a
4029 sub-process (such as a stand-alone simulator) and then communicates
4030 with that. The sub-program to run is specified using the syntax
4031 ``|<program> <args>'' vis:
4033 (gdb) set remotedebug 1
4034 (gdb) target extended-remote |mn10300-elf-sim program-args
4036 * MIPS 64 remote protocol
4038 A long standing bug in the mips64 remote protocol where by GDB
4039 expected certain 32 bit registers (ex SR) to be transfered as 32
4040 instead of 64 bits has been fixed.
4042 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4043 added to provide backward compatibility with older versions of GDB.
4045 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4047 The command ``set remotebinarydownload'' command has been replaced by
4048 ``set remote X-packet''. Other commands in ``set remote'' family
4049 include ``set remote P-packet''.
4051 * Breakpoint commands accept ranges.
4053 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4054 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4055 ``tracepoint passcount'' also accepts a range of tracepoints.
4057 * ``apropos'' command added.
4059 The ``apropos'' command searches through command names and
4060 documentation strings, printing out matches, making it much easier to
4061 try to find a command that does what you are looking for.
4065 A new machine oriented interface (MI) has been added to GDB. This
4066 interface is designed for debug environments running GDB as a separate
4067 process. This is part of the long term libGDB project. See the
4068 "GDB/MI" chapter of the GDB manual for further information. It can be
4069 enabled by configuring with:
4071 .../configure --enable-gdbmi
4073 *** Changes in GDB-4.18:
4075 * New native configurations
4077 HP-UX 10.20 hppa*-*-hpux10.20
4078 HP-UX 11.x hppa*-*-hpux11.0*
4079 M68K GNU/Linux m68*-*-linux*
4083 Fujitsu FR30 fr30-*-elf*
4084 Intel StrongARM strongarm-*-*
4085 Mitsubishi D30V d30v-*-*
4087 * OBSOLETE configurations
4089 Gould PowerNode, NP1 np1-*-*, pn-*-*
4091 Configurations that have been declared obsolete will be commented out,
4092 but the code will be left in place. If there is no activity to revive
4093 these configurations before the next release of GDB, the sources will
4094 be permanently REMOVED.
4098 As a compatibility experiment, GDB's source files buildsym.h and
4099 buildsym.c have been converted to pure standard C, no longer
4100 containing any K&R compatibility code. We believe that all systems in
4101 use today either come with a standard C compiler, or have a GCC port
4102 available. If this is not true, please report the affected
4103 configuration to bug-gdb@gnu.org immediately. See the README file for
4104 information about getting a standard C compiler if you don't have one
4109 GDB now uses readline 2.2.
4111 * set extension-language
4113 You can now control the mapping between filename extensions and source
4114 languages by using the `set extension-language' command. For instance,
4115 you can ask GDB to treat .c files as C++ by saying
4116 set extension-language .c c++
4117 The command `info extensions' lists all of the recognized extensions
4118 and their associated languages.
4120 * Setting processor type for PowerPC and RS/6000
4122 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4123 you can use the `set processor' command to specify what variant of the
4124 PowerPC family you are debugging. The command
4128 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4129 following PowerPC and RS6000 variants:
4131 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4132 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4134 403GC IBM PowerPC 403GC
4135 505 Motorola PowerPC 505
4136 860 Motorola PowerPC 860 or 850
4137 601 Motorola PowerPC 601
4138 602 Motorola PowerPC 602
4139 603 Motorola/IBM PowerPC 603 or 603e
4140 604 Motorola PowerPC 604 or 604e
4141 750 Motorola/IBM PowerPC 750 or 750
4143 At the moment, this command just tells GDB what to name the
4144 special-purpose processor registers. Since almost all the affected
4145 registers are inaccessible to user-level programs, this command is
4146 only useful for remote debugging in its present form.
4150 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4151 more extensive support for HP-UX. Added features include shared
4152 library support, kernel threads and hardware watchpoints for 11.00,
4153 support for HP's ANSI C and C++ compilers, and a compatibility mode
4154 for xdb and dbx commands.
4158 HP's donation includes the new concept of catchpoints, which is a
4159 generalization of the old catch command. On HP-UX, it is now possible
4160 to catch exec, fork, and vfork, as well as library loading.
4162 This means that the existing catch command has changed; its first
4163 argument now specifies the type of catch to be set up. See the
4164 output of "help catch" for a list of catchpoint types.
4166 * Debugging across forks
4168 On HP-UX, you can choose which process to debug when a fork() happens
4173 HP has donated a curses-based terminal user interface (TUI). To get
4174 it, build with --enable-tui. Although this can be enabled for any
4175 configuration, at present it only works for native HP debugging.
4177 * GDB remote protocol additions
4179 A new protocol packet 'X' that writes binary data is now available.
4180 Default behavior is to try 'X', then drop back to 'M' if the stub
4181 fails to respond. The settable variable `remotebinarydownload'
4182 allows explicit control over the use of 'X'.
4184 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4185 full 64-bit address. The command
4187 set remoteaddresssize 32
4189 can be used to revert to the old behaviour. For existing remote stubs
4190 the change should not be noticed, as the additional address information
4193 In order to assist in debugging stubs, you may use the maintenance
4194 command `packet' to send any text string to the stub. For instance,
4196 maint packet heythere
4198 sends the packet "$heythere#<checksum>". Note that it is very easy to
4199 disrupt a debugging session by sending the wrong packet at the wrong
4202 The compare-sections command allows you to compare section data on the
4203 target to what is in the executable file without uploading or
4204 downloading, by comparing CRC checksums.
4206 * Tracing can collect general expressions
4208 You may now collect general expressions at tracepoints. This requires
4209 further additions to the target-side stub; see tracepoint.c and
4210 doc/agentexpr.texi for further details.
4212 * mask-address variable for Mips
4214 For Mips targets, you may control the zeroing of the upper 32 bits of
4215 a 64-bit address by entering `set mask-address on'. This is mainly
4216 of interest to users of embedded R4xxx and R5xxx processors.
4218 * Higher serial baud rates
4220 GDB's serial code now allows you to specify baud rates 57600, 115200,
4221 230400, and 460800 baud. (Note that your host system may not be able
4222 to achieve all of these rates.)
4226 The i960 configuration now includes an initial implementation of a
4227 builtin simulator, contributed by Jim Wilson.
4230 *** Changes in GDB-4.17:
4232 * New native configurations
4234 Alpha GNU/Linux alpha*-*-linux*
4235 Unixware 2.x i[3456]86-unixware2*
4236 Irix 6.x mips*-sgi-irix6*
4237 PowerPC GNU/Linux powerpc-*-linux*
4238 PowerPC Solaris powerpcle-*-solaris*
4239 Sparc GNU/Linux sparc-*-linux*
4240 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4244 Argonaut Risc Chip (ARC) arc-*-*
4245 Hitachi H8/300S h8300*-*-*
4246 Matsushita MN10200 w/simulator mn10200-*-*
4247 Matsushita MN10300 w/simulator mn10300-*-*
4248 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4249 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4250 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4251 Mitsubishi D10V w/simulator d10v-*-*
4252 Mitsubishi M32R/D w/simulator m32r-*-elf*
4253 Tsqware Sparclet sparclet-*-*
4254 NEC V850 w/simulator v850-*-*
4256 * New debugging protocols
4258 ARM with RDI protocol arm*-*-*
4259 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4260 DDB and LSI variants of PMON protocol mips*-*-*
4261 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4262 PowerPC with SDS protocol powerpc{,le}-*-eabi
4263 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4267 All configurations can now understand and use the DWARF 2 debugging
4268 format. The choice is automatic, if the symbol file contains DWARF 2
4273 GDB now includes basic Java language support. This support is
4274 only useful with Java compilers that produce native machine code.
4276 * solib-absolute-prefix and solib-search-path
4278 For SunOS and SVR4 shared libraries, you may now set the prefix for
4279 loading absolute shared library symbol files, and the search path for
4280 locating non-absolute shared library symbol files.
4282 * Live range splitting
4284 GDB can now effectively debug code for which GCC has performed live
4285 range splitting as part of its optimization. See gdb/doc/LRS for
4286 more details on the expected format of the stabs information.
4290 GDB's support for the GNU Hurd, including thread debugging, has been
4291 updated to work with current versions of the Hurd.
4295 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4296 instruction set. ARM GDB automatically detects when Thumb
4297 instructions are in use, and adjusts disassembly and backtracing
4302 GDB's MIPS target configurations now handle the MIP16 16-bit
4307 GDB now includes support for overlays; if an executable has been
4308 linked such that multiple sections are based at the same address, GDB
4309 will decide which section to use for symbolic info. You can choose to
4310 control the decision manually, using overlay commands, or implement
4311 additional target-side support and use "overlay load-target" to bring
4312 in the overlay mapping. Do "help overlay" for more detail.
4316 The command "info symbol <address>" displays information about
4317 the symbol at the specified address.
4321 The standard remote protocol now includes an extension that allows
4322 asynchronous collection and display of trace data. This requires
4323 extensive support in the target-side debugging stub. Tracing mode
4324 includes a new interaction mode in GDB and new commands: see the
4325 file tracepoint.c for more details.
4329 Configurations for embedded MIPS now include a simulator contributed
4330 by Cygnus Solutions. The simulator supports the instruction sets
4331 of most MIPS variants.
4335 Sparc configurations may now include the ERC32 simulator contributed
4336 by the European Space Agency. The simulator is not built into
4337 Sparc targets by default; configure with --enable-sim to include it.
4341 For target configurations that may include multiple variants of a
4342 basic architecture (such as MIPS and SH), you may now set the
4343 architecture explicitly. "set arch" sets, "info arch" lists
4344 the possible architectures.
4346 *** Changes in GDB-4.16:
4348 * New native configurations
4350 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4351 M68K NetBSD m68k-*-netbsd*
4352 PowerPC AIX 4.x powerpc-*-aix*
4353 PowerPC MacOS powerpc-*-macos*
4354 PowerPC Windows NT powerpcle-*-cygwin32
4355 RS/6000 AIX 4.x rs6000-*-aix4*
4359 ARM with RDP protocol arm-*-*
4360 I960 with MON960 i960-*-coff
4361 MIPS VxWorks mips*-*-vxworks*
4362 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4363 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4365 Matra Sparclet sparclet-*-*
4369 The powerpc-eabi configuration now includes the PSIM simulator,
4370 contributed by Andrew Cagney, with assistance from Mike Meissner.
4371 PSIM is a very elaborate model of the PowerPC, including not only
4372 basic instruction set execution, but also details of execution unit
4373 performance and I/O hardware. See sim/ppc/README for more details.
4377 GDB now works with Solaris 2.5.
4379 * Windows 95/NT native
4381 GDB will now work as a native debugger on Windows 95 and Windows NT.
4382 To build it from source, you must use the "gnu-win32" environment,
4383 which uses a DLL to emulate enough of Unix to run the GNU tools.
4384 Further information, binaries, and sources are available at
4385 ftp.cygnus.com, under pub/gnu-win32.
4387 * dont-repeat command
4389 If a user-defined command includes the command `dont-repeat', then the
4390 command will not be repeated if the user just types return. This is
4391 useful if the command is time-consuming to run, so that accidental
4392 extra keystrokes don't run the same command many times.
4394 * Send break instead of ^C
4396 The standard remote protocol now includes an option to send a break
4397 rather than a ^C to the target in order to interrupt it. By default,
4398 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4400 * Remote protocol timeout
4402 The standard remote protocol includes a new variable `remotetimeout'
4403 that allows you to set the number of seconds before GDB gives up trying
4404 to read from the target. The default value is 2.
4406 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4408 By default GDB will automatically keep track of objects as they are
4409 loaded and unloaded by the dynamic linker. By using the command `set
4410 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4411 when shared library events occur, thus allowing you to set breakpoints
4412 in shared libraries which are explicitly loaded by the inferior.
4414 Note this feature does not work on hpux8. On hpux9 you must link
4415 /usr/lib/end.o into your program. This feature should work
4416 automatically on hpux10.
4418 * Irix 5.x hardware watchpoint support
4420 Irix 5 configurations now support the use of hardware watchpoints.
4422 * Mips protocol "SYN garbage limit"
4424 When debugging a Mips target using the `target mips' protocol, you
4425 may set the number of characters that GDB will ignore by setting
4426 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4427 every character. The default value is 1050.
4429 * Recording and replaying remote debug sessions
4431 If you set `remotelogfile' to the name of a file, gdb will write to it
4432 a recording of a remote debug session. This recording may then be
4433 replayed back to gdb using "gdbreplay". See gdbserver/README for
4434 details. This is useful when you have a problem with GDB while doing
4435 remote debugging; you can make a recording of the session and send it
4436 to someone else, who can then recreate the problem.
4438 * Speedups for remote debugging
4440 GDB includes speedups for downloading and stepping MIPS systems using
4441 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4442 and more efficient S-record downloading.
4444 * Memory use reductions and statistics collection
4446 GDB now uses less memory and reports statistics about memory usage.
4447 Try the `maint print statistics' command, for example.
4449 *** Changes in GDB-4.15:
4451 * Psymtabs for XCOFF
4453 The symbol reader for AIX GDB now uses partial symbol tables. This
4454 can greatly improve startup time, especially for large executables.
4456 * Remote targets use caching
4458 Remote targets now use a data cache to speed up communication with the
4459 remote side. The data cache could lead to incorrect results because
4460 it doesn't know about volatile variables, thus making it impossible to
4461 debug targets which use memory mapped I/O devices. `set remotecache
4462 off' turns the the data cache off.
4464 * Remote targets may have threads
4466 The standard remote protocol now includes support for multiple threads
4467 in the target system, using new protocol commands 'H' and 'T'. See
4468 gdb/remote.c for details.
4472 If GDB is configured with `--enable-netrom', then it will include
4473 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4474 acts as though it is a bank of ROM on the target board, but you can
4475 write into it over the network. GDB's support consists only of
4476 support for fast loading into the emulated ROM; to debug, you must use
4477 another protocol, such as standard remote protocol. The usual
4478 sequence is something like
4480 target nrom <netrom-hostname>
4482 target remote <netrom-hostname>:1235
4486 GDB now includes support for the Apple Macintosh, as a host only. It
4487 may be run as either an MPW tool or as a standalone application, and
4488 it can debug through the serial port. All the usual GDB commands are
4489 available, but to the target command, you must supply "serial" as the
4490 device type instead of "/dev/ttyXX". See mpw-README in the main
4491 directory for more information on how to build. The MPW configuration
4492 scripts */mpw-config.in support only a few targets, and only the
4493 mips-idt-ecoff target has been tested.
4497 GDB configuration now uses autoconf. This is not user-visible,
4498 but does simplify configuration and building.
4502 GDB now supports hpux10.
4504 *** Changes in GDB-4.14:
4506 * New native configurations
4508 x86 FreeBSD i[345]86-*-freebsd
4509 x86 NetBSD i[345]86-*-netbsd
4510 NS32k NetBSD ns32k-*-netbsd
4511 Sparc NetBSD sparc-*-netbsd
4515 A29K VxWorks a29k-*-vxworks
4516 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4517 CPU32 EST-300 emulator m68*-*-est*
4518 PowerPC ELF powerpc-*-elf
4521 * Alpha OSF/1 support for procfs
4523 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4524 possible to attach to running processes. As the mounting of the /proc
4525 filesystem is optional on the Alpha, GDB automatically determines
4526 the availability of /proc during startup. This can lead to problems
4527 if /proc is unmounted after GDB has been started.
4529 * Arguments to user-defined commands
4531 User commands may accept up to 10 arguments separated by whitespace.
4532 Arguments are accessed within the user command via $arg0..$arg9. A
4535 print $arg0 + $arg1 + $arg2
4537 To execute the command use:
4540 Defines the command "adder" which prints the sum of its three arguments.
4541 Note the arguments are text substitutions, so they may reference variables,
4542 use complex expressions, or even perform inferior function calls.
4544 * New `if' and `while' commands
4546 This makes it possible to write more sophisticated user-defined
4547 commands. Both commands take a single argument, which is the
4548 expression to evaluate, and must be followed by the commands to
4549 execute, one per line, if the expression is nonzero, the list being
4550 terminated by the word `end'. The `if' command list may include an
4551 `else' word, which causes the following commands to be executed only
4552 if the expression is zero.
4554 * Fortran source language mode
4556 GDB now includes partial support for Fortran 77. It will recognize
4557 Fortran programs and can evaluate a subset of Fortran expressions, but
4558 variables and functions may not be handled correctly. GDB will work
4559 with G77, but does not yet know much about symbols emitted by other
4562 * Better HPUX support
4564 Most debugging facilities now work on dynamic executables for HPPAs
4565 running hpux9 or later. You can attach to running dynamically linked
4566 processes, but by default the dynamic libraries will be read-only, so
4567 for instance you won't be able to put breakpoints in them. To change
4568 that behavior do the following before running the program:
4574 This will cause the libraries to be mapped private and read-write.
4575 To revert to the normal behavior, do this:
4581 You cannot set breakpoints or examine data in the library until after
4582 the library is loaded if the function/data symbols do not have
4585 GDB can now also read debug symbols produced by the HP C compiler on
4586 HPPAs (sorry, no C++, Fortran or 68k support).
4588 * Target byte order now dynamically selectable
4590 You can choose which byte order to use with a target system, via the
4591 commands "set endian big" and "set endian little", and you can see the
4592 current setting by using "show endian". You can also give the command
4593 "set endian auto", in which case GDB will use the byte order
4594 associated with the executable. Currently, only embedded MIPS
4595 configurations support dynamic selection of target byte order.
4597 * New DOS host serial code
4599 This version uses DPMI interrupts to handle buffered I/O, so you
4600 no longer need to run asynctsr when debugging boards connected to
4603 *** Changes in GDB-4.13:
4605 * New "complete" command
4607 This lists all the possible completions for the rest of the line, if it
4608 were to be given as a command itself. This is intended for use by emacs.
4610 * Trailing space optional in prompt
4612 "set prompt" no longer adds a space for you after the prompt you set. This
4613 allows you to set a prompt which ends in a space or one that does not.
4615 * Breakpoint hit counts
4617 "info break" now displays a count of the number of times the breakpoint
4618 has been hit. This is especially useful in conjunction with "ignore"; you
4619 can ignore a large number of breakpoint hits, look at the breakpoint info
4620 to see how many times the breakpoint was hit, then run again, ignoring one
4621 less than that number, and this will get you quickly to the last hit of
4624 * Ability to stop printing at NULL character
4626 "set print null-stop" will cause GDB to stop printing the characters of
4627 an array when the first NULL is encountered. This is useful when large
4628 arrays actually contain only short strings.
4630 * Shared library breakpoints
4632 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4633 breakpoints in shared libraries before the executable is run.
4635 * Hardware watchpoints
4637 There is a new hardware breakpoint for the watch command for sparclite
4638 targets. See gdb/sparclite/hw_breakpoint.note.
4640 Hardware watchpoints are also now supported under GNU/Linux.
4644 Annotations have been added. These are for use with graphical interfaces,
4645 and are still experimental. Currently only gdba.el uses these.
4647 * Improved Irix 5 support
4649 GDB now works properly with Irix 5.2.
4651 * Improved HPPA support
4653 GDB now works properly with the latest GCC and GAS.
4655 * New native configurations
4657 Sequent PTX4 i[34]86-sequent-ptx4
4658 HPPA running OSF/1 hppa*-*-osf*
4659 Atari TT running SVR4 m68*-*-sysv4*
4660 RS/6000 LynxOS rs6000-*-lynxos*
4664 OS/9000 i[34]86-*-os9k
4665 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4668 * Hitachi SH7000 and E7000-PC ICE support
4670 There is now support for communicating with the Hitachi E7000-PC ICE.
4671 This is available automatically when GDB is configured for the SH.
4675 As usual, a variety of small fixes and improvements, both generic
4676 and configuration-specific. See the ChangeLog for more detail.
4678 *** Changes in GDB-4.12:
4680 * Irix 5 is now supported
4684 GDB-4.12 on the HPPA has a number of changes which make it unable
4685 to debug the output from the currently released versions of GCC and
4686 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4687 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4688 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4691 *** Changes in GDB-4.11:
4693 * User visible changes:
4697 The "set remotedebug" option is now consistent between the mips remote
4698 target, remote targets using the gdb-specific protocol, UDI (AMD's
4699 debug protocol for the 29k) and the 88k bug monitor. It is now an
4700 integer specifying a debug level (normally 0 or 1, but 2 means more
4701 debugging info for the mips target).
4703 * DEC Alpha native support
4705 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4706 debug info, but GDB works fairly well with the DEC compiler and should
4707 work with a future GCC release. See the README file for a few
4708 Alpha-specific notes.
4710 * Preliminary thread implementation
4712 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4714 * LynxOS native and target support for 386
4716 This release has been hosted on LynxOS 2.2, and also can be configured
4717 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4720 * Improvements in C++ mangling/demangling.
4722 This release has much better g++ debugging, specifically in name
4723 mangling/demangling, virtual function calls, print virtual table,
4724 call methods, ...etc.
4726 *** Changes in GDB-4.10:
4728 * User visible changes:
4730 Remote debugging using the GDB-specific (`target remote') protocol now
4731 supports the `load' command. This is only useful if you have some
4732 other way of getting the stub to the target system, and you can put it
4733 somewhere in memory where it won't get clobbered by the download.
4735 Filename completion now works.
4737 When run under emacs mode, the "info line" command now causes the
4738 arrow to point to the line specified. Also, "info line" prints
4739 addresses in symbolic form (as well as hex).
4741 All vxworks based targets now support a user settable option, called
4742 vxworks-timeout. This option represents the number of seconds gdb
4743 should wait for responses to rpc's. You might want to use this if
4744 your vxworks target is, perhaps, a slow software simulator or happens
4745 to be on the far side of a thin network line.
4749 This release contains support for using a DEC alpha as a GDB host for
4750 cross debugging. Native alpha debugging is not supported yet.
4753 *** Changes in GDB-4.9:
4757 This is the first GDB release which is accompanied by a matching testsuite.
4758 The testsuite requires installation of dejagnu, which should be available
4759 via ftp from most sites that carry GNU software.
4763 'Cfront' style demangling has had its name changed to 'ARM' style, to
4764 emphasize that it was written from the specifications in the C++ Annotated
4765 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4766 disclaimers, it still generated too much confusion with users attempting to
4767 use gdb with AT&T cfront.
4771 GDB now uses a standard remote interface to a simulator library.
4772 So far, the library contains simulators for the Zilog Z8001/2, the
4773 Hitachi H8/300, H8/500 and Super-H.
4775 * New targets supported
4777 H8/300 simulator h8300-hitachi-hms or h8300hms
4778 H8/500 simulator h8500-hitachi-hms or h8500hms
4779 SH simulator sh-hitachi-hms or sh
4780 Z8000 simulator z8k-zilog-none or z8ksim
4781 IDT MIPS board over serial line mips-idt-ecoff
4783 Cross-debugging to GO32 targets is supported. It requires a custom
4784 version of the i386-stub.c module which is integrated with the
4785 GO32 memory extender.
4787 * New remote protocols
4789 MIPS remote debugging protocol.
4791 * New source languages supported
4793 This version includes preliminary support for Chill, a Pascal like language
4794 used by telecommunications companies. Chill support is also being integrated
4795 into the GNU compiler, but we don't know when it will be publically available.
4798 *** Changes in GDB-4.8:
4800 * HP Precision Architecture supported
4802 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4803 version of this support was available as a set of patches from the
4804 University of Utah. GDB does not support debugging of programs
4805 compiled with the HP compiler, because HP will not document their file
4806 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4807 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4809 Many problems in the preliminary version have been fixed.
4811 * Faster and better demangling
4813 We have improved template demangling and fixed numerous bugs in the GNU style
4814 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4815 character types (wchar_t) are now supported. Demangling of each symbol is now
4816 only done once, and is cached when the symbol table for a file is read in.
4817 This results in a small increase in memory usage for C programs, a moderate
4818 increase in memory usage for C++ programs, and a fantastic speedup in
4821 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4822 from the specifications in the Annotated Reference Manual, which AT&T's
4823 compiler does not actually implement.
4825 * G++ multiple inheritance compiler problem
4827 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4828 inheritance lattices was reworked to properly discover ambiguities. We
4829 recently found an example which causes this new algorithm to fail in a
4830 very subtle way, producing bad debug information for those classes.
4831 The file 'gcc.patch' (in this directory) can be applied to gcc to
4832 circumvent the problem. A future GCC release will contain a complete
4835 The previous G++ debug info problem (mentioned below for the gdb-4.7
4836 release) is fixed in gcc version 2.3.2.
4838 * Improved configure script
4840 The `configure' script will now attempt to guess your system type if
4841 you don't supply a host system type. The old scheme of supplying a
4842 host system triplet is preferable over using this. All the magic is
4843 done in the new `config.guess' script. Examine it for details.
4845 We have also brought our configure script much more in line with the FSF's
4846 version. It now supports the --with-xxx options. In particular,
4847 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4848 The resulting GDB will not be able to read arbitrary object file formats --
4849 only the format ``expected'' to be used on the configured target system.
4850 We hope to make this the default in a future release.
4852 * Documentation improvements
4854 There's new internal documentation on how to modify GDB, and how to
4855 produce clean changes to the code. We implore people to read it
4856 before submitting changes.
4858 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4859 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4860 `info' files are also provided. To build `info' files from scratch,
4861 you will need the latest `makeinfo' release, which will be available in
4862 a future texinfo-X.Y release.
4864 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4865 We're not sure exactly which versions have this problem, but it has
4866 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4867 or better. If that isn't possible, there is a patch in
4868 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4869 around this problem.
4873 GDB now supports array constants that can be used in expressions typed in by
4874 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4875 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4878 The new directory `gdb/sparclite' contains a program that demonstrates
4879 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4881 * New native hosts supported
4883 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4884 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4886 * New targets supported
4888 AMD 29k family via UDI a29k-amd-udi or udi29k
4890 * New file formats supported
4892 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4893 HPUX core files, and SCO 3.2v2 core files.
4897 Attaching to processes now works again; thanks for the many bug reports.
4899 We have also stomped on a bunch of core dumps caused by
4900 printf_filtered("%s") problems.
4902 We eliminated a copyright problem on the rpc and ptrace header files
4903 for VxWorks, which was discovered at the last minute during the 4.7
4904 release. You should now be able to build a VxWorks GDB.
4906 You can now interrupt gdb while an attached process is running. This
4907 will cause the attached process to stop, and give control back to GDB.
4909 We fixed problems caused by using too many file descriptors
4910 for reading symbols from object files and libraries. This was
4911 especially a problem for programs that used many (~100) shared
4914 The `step' command now only enters a subroutine if there is line number
4915 information for the subroutine. Otherwise it acts like the `next'
4916 command. Previously, `step' would enter subroutines if there was
4917 any debugging information about the routine. This avoids problems
4918 when using `cc -g1' on MIPS machines.
4920 * Internal improvements
4922 GDB's internal interfaces have been improved to make it easier to support
4923 debugging of multiple languages in the future.
4925 GDB now uses a common structure for symbol information internally.
4926 Minimal symbols (derived from linkage symbols in object files), partial
4927 symbols (from a quick scan of debug information), and full symbols
4928 contain a common subset of information, making it easier to write
4929 shared code that handles any of them.
4931 * New command line options
4933 We now accept --silent as an alias for --quiet.
4937 The memory-mapped-malloc library is now licensed under the GNU Library
4938 General Public License.
4940 *** Changes in GDB-4.7:
4942 * Host/native/target split
4944 GDB has had some major internal surgery to untangle the support for
4945 hosts and remote targets. Now, when you configure GDB for a remote
4946 target, it will no longer load in all of the support for debugging
4947 local programs on the host. When fully completed and tested, this will
4948 ensure that arbitrary host/target combinations are possible.
4950 The primary conceptual shift is to separate the non-portable code in
4951 GDB into three categories. Host specific code is required any time GDB
4952 is compiled on that host, regardless of the target. Target specific
4953 code relates to the peculiarities of the target, but can be compiled on
4954 any host. Native specific code is everything else: it can only be
4955 built when the host and target are the same system. Child process
4956 handling and core file support are two common `native' examples.
4958 GDB's use of /proc for controlling Unix child processes is now cleaner.
4959 It has been split out into a single module under the `target_ops' vector,
4960 plus two native-dependent functions for each system that uses /proc.
4962 * New hosts supported
4964 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4965 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4966 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4968 * New targets supported
4970 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4971 68030 and CPU32 m68030-*-*, m68332-*-*
4973 * New native hosts supported
4975 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4976 (386bsd is not well tested yet)
4977 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4979 * New file formats supported
4981 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4982 supports reading of `a.out.adobe' object files, which are an a.out
4983 format extended with minimal information about multiple sections.
4987 `show copying' is the same as the old `info copying'.
4988 `show warranty' is the same as `info warrantee'.
4989 These were renamed for consistency. The old commands continue to work.
4991 `info handle' is a new alias for `info signals'.
4993 You can now define pre-command hooks, which attach arbitrary command
4994 scripts to any command. The commands in the hook will be executed
4995 prior to the user's command. You can also create a hook which will be
4996 executed whenever the program stops. See gdb.texinfo.
5000 We now deal with Cfront style name mangling, and can even extract type
5001 info from mangled symbols. GDB can automatically figure out which
5002 symbol mangling style your C++ compiler uses.
5004 Calling of methods and virtual functions has been improved as well.
5008 The crash that occured when debugging Sun Ansi-C compiled binaries is
5009 fixed. This was due to mishandling of the extra N_SO stabs output
5012 We also finally got Ultrix 4.2 running in house, and fixed core file
5013 support, with help from a dozen people on the net.
5015 John M. Farrell discovered that the reason that single-stepping was so
5016 slow on all of the Mips based platforms (primarily SGI and DEC) was
5017 that we were trying to demangle and lookup a symbol used for internal
5018 purposes on every instruction that was being stepped through. Changing
5019 the name of that symbol so that it couldn't be mistaken for a C++
5020 mangled symbol sped things up a great deal.
5022 Rich Pixley sped up symbol lookups in general by getting much smarter
5023 about when C++ symbol mangling is necessary. This should make symbol
5024 completion (TAB on the command line) much faster. It's not as fast as
5025 we'd like, but it's significantly faster than gdb-4.6.
5029 A new user controllable variable 'call_scratch_address' can
5030 specify the location of a scratch area to be used when GDB
5031 calls a function in the target. This is necessary because the
5032 usual method of putting the scratch area on the stack does not work
5033 in systems that have separate instruction and data spaces.
5035 We integrated changes to support the 29k UDI (Universal Debugger
5036 Interface), but discovered at the last minute that we didn't have all
5037 of the appropriate copyright paperwork. We are working with AMD to
5038 resolve this, and hope to have it available soon.
5042 We have sped up the remote serial line protocol, especially for targets
5043 with lots of registers. It now supports a new `expedited status' ('T')
5044 message which can be used in place of the existing 'S' status message.
5045 This allows the remote stub to send only the registers that GDB
5046 needs to make a quick decision about single-stepping or conditional
5047 breakpoints, eliminating the need to fetch the entire register set for
5048 each instruction being stepped through.
5050 The GDB remote serial protocol now implements a write-through cache for
5051 registers, only re-reading the registers if the target has run.
5053 There is also a new remote serial stub for SPARC processors. You can
5054 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5055 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5056 processor with a serial port.
5060 Configure.in files have become much easier to read and modify. A new
5061 `table driven' format makes it more obvious what configurations are
5062 supported, and what files each one uses.
5066 There is a new opcodes library which will eventually contain all of the
5067 disassembly routines and opcode tables. At present, it only contains
5068 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5069 disassembler (binutils/objdump) to share these routines.
5071 The libiberty library is now copylefted under the GNU Library General
5072 Public License. This allows more liberal use, and was done so libg++
5073 can use it. This makes no difference to GDB, since the Library License
5074 grants all the rights from the General Public License.
5078 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5079 reference to the stabs symbol info used by the debugger. It is (as far
5080 as we know) the only published document on this fascinating topic. We
5081 encourage you to read it, compare it to the stabs information on your
5082 system, and send improvements on the document in general (to
5083 bug-gdb@prep.ai.mit.edu).
5085 And, of course, many bugs have been fixed.
5088 *** Changes in GDB-4.6:
5090 * Better support for C++ function names
5092 GDB now accepts as input the "demangled form" of C++ overloaded function
5093 names and member function names, and can do command completion on such names
5094 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5095 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5096 Make use of command completion, it is your friend.
5098 GDB also now accepts a variety of C++ mangled symbol formats. They are
5099 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5100 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5101 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5102 for the list of formats.
5104 * G++ symbol mangling problem
5106 Recent versions of gcc have a bug in how they emit debugging information for
5107 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5108 directory) can be applied to gcc to fix the problem. Alternatively, if you
5109 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5110 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5111 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5114 * New 'maintenance' command
5116 All of the commands related to hacking GDB internals have been moved out of
5117 the main command set, and now live behind the 'maintenance' command. This
5118 can also be abbreviated as 'mt'. The following changes were made:
5120 dump-me -> maintenance dump-me
5121 info all-breakpoints -> maintenance info breakpoints
5122 printmsyms -> maintenance print msyms
5123 printobjfiles -> maintenance print objfiles
5124 printpsyms -> maintenance print psymbols
5125 printsyms -> maintenance print symbols
5127 The following commands are new:
5129 maintenance demangle Call internal GDB demangler routine to
5130 demangle a C++ link name and prints the result.
5131 maintenance print type Print a type chain for a given symbol
5133 * Change to .gdbinit file processing
5135 We now read the $HOME/.gdbinit file before processing the argv arguments
5136 (e.g. reading symbol files or core files). This allows global parameters to
5137 be set, which will apply during the symbol reading. The ./.gdbinit is still
5138 read after argv processing.
5140 * New hosts supported
5142 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5144 GNU/Linux support i386-unknown-linux or linux
5146 We are also including code to support the HP/PA running BSD and HPUX. This
5147 is almost guaranteed not to work, as we didn't have time to test or build it
5148 for this release. We are including it so that the more adventurous (or
5149 masochistic) of you can play with it. We also had major problems with the
5150 fact that the compiler that we got from HP doesn't support the -g option.
5153 * New targets supported
5155 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5157 * More smarts about finding #include files
5159 GDB now remembers the compilation directory for all include files, and for
5160 all files from which C is generated (like yacc and lex sources). This
5161 greatly improves GDB's ability to find yacc/lex sources, and include files,
5162 especially if you are debugging your program from a directory different from
5163 the one that contains your sources.
5165 We also fixed a bug which caused difficulty with listing and setting
5166 breakpoints in include files which contain C code. (In the past, you had to
5167 try twice in order to list an include file that you hadn't looked at before.)
5169 * Interesting infernals change
5171 GDB now deals with arbitrary numbers of sections, where the symbols for each
5172 section must be relocated relative to that section's landing place in the
5173 target's address space. This work was needed to support ELF with embedded
5174 stabs used by Solaris-2.0.
5176 * Bug fixes (of course!)
5178 There have been loads of fixes for the following things:
5179 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5180 i960, stabs, DOS(GO32), procfs, etc...
5182 See the ChangeLog for details.
5184 *** Changes in GDB-4.5:
5186 * New machines supported (host and target)
5188 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5190 SGI Irix-4.x mips-sgi-irix4 or iris4
5192 * New malloc package
5194 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5195 Mmalloc is capable of handling mutiple heaps of memory. It is also
5196 capable of saving a heap to a file, and then mapping it back in later.
5197 This can be used to greatly speedup the startup of GDB by using a
5198 pre-parsed symbol table which lives in a mmalloc managed heap. For
5199 more details, please read mmalloc/mmalloc.texi.
5203 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5204 'help info proc' for details.
5206 * MIPS ecoff symbol table format
5208 The code that reads MIPS symbol table format is now supported on all hosts.
5209 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5212 * File name changes for MS-DOS
5214 Many files in the config directories have been renamed to make it easier to
5215 support GDB on MS-DOSe systems (which have very restrictive file name
5216 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5217 environment) is close to working but has some remaining problems. Note
5218 that debugging of DOS programs is not supported, due to limitations
5219 in the ``operating system'', but it can be used to host cross-debugging.
5221 * Cross byte order fixes
5223 Many fixes have been made to support cross debugging of Sparc and MIPS
5224 targets from hosts whose byte order differs.
5226 * New -mapped and -readnow options
5228 If memory-mapped files are available on your system through the 'mmap'
5229 system call, you can use the -mapped option on the `file' or
5230 `symbol-file' commands to cause GDB to write the symbols from your
5231 program into a reusable file. If the program you are debugging is
5232 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5233 Future GDB debugging sessions will notice the presence of this file,
5234 and will quickly map in symbol information from it, rather than reading
5235 the symbol table from the executable program. Using the '-mapped'
5236 option in a GDB `file' or `symbol-file' command has the same effect as
5237 starting GDB with the '-mapped' command-line option.
5239 You can cause GDB to read the entire symbol table immediately by using
5240 the '-readnow' option with any of the commands that load symbol table
5241 information (or on the GDB command line). This makes the command
5242 slower, but makes future operations faster.
5244 The -mapped and -readnow options are typically combined in order to
5245 build a `fred.syms' file that contains complete symbol information.
5246 A simple GDB invocation to do nothing but build a `.syms' file for future
5249 gdb -batch -nx -mapped -readnow programname
5251 The `.syms' file is specific to the host machine on which GDB is run.
5252 It holds an exact image of GDB's internal symbol table. It cannot be
5253 shared across multiple host platforms.
5255 * longjmp() handling
5257 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5258 siglongjmp() without losing control. This feature has not yet been ported to
5259 all systems. It currently works on many 386 platforms, all MIPS-based
5260 platforms (SGI, DECstation, etc), and Sun3/4.
5264 Preliminary work has been put in to support the new Solaris OS from Sun. At
5265 this time, it can control and debug processes, but it is not capable of
5270 As always, many many bug fixes. The major areas were with g++, and mipsread.
5271 People using the MIPS-based platforms should experience fewer mysterious
5272 crashes and trashed symbol tables.
5274 *** Changes in GDB-4.4:
5276 * New machines supported (host and target)
5278 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5280 BSD Reno on Vax vax-dec-bsd
5281 Ultrix on Vax vax-dec-ultrix
5283 * New machines supported (target)
5285 AMD 29000 embedded, using EBMON a29k-none-none
5289 GDB continues to improve its handling of C++. `References' work better.
5290 The demangler has also been improved, and now deals with symbols mangled as
5291 per the Annotated C++ Reference Guide.
5293 GDB also now handles `stabs' symbol information embedded in MIPS
5294 `ecoff' symbol tables. Since the ecoff format was not easily
5295 extensible to handle new languages such as C++, this appeared to be a
5296 good way to put C++ debugging info into MIPS binaries. This option
5297 will be supported in the GNU C compiler, version 2, when it is
5300 * New features for SVR4
5302 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5303 shared libraries. Debugging dynamically linked programs should present
5304 only minor differences from debugging statically linked programs.
5306 The `info proc' command will print out information about any process
5307 on an SVR4 system (including the one you are debugging). At the moment,
5308 it prints the address mappings of the process.
5310 If you bring up GDB on another SVR4 system, please send mail to
5311 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5313 * Better dynamic linking support in SunOS
5315 Reading symbols from shared libraries which contain debugging symbols
5316 now works properly. However, there remain issues such as automatic
5317 skipping of `transfer vector' code during function calls, which
5318 make it harder to debug code in a shared library, than to debug the
5319 same code linked statically.
5323 GDB is now using the latest `getopt' routines from the FSF. This
5324 version accepts the -- prefix for options with long names. GDB will
5325 continue to accept the old forms (-option and +option) as well.
5326 Various single letter abbreviations for options have been explicity
5327 added to the option table so that they won't get overshadowed in the
5328 future by other options that begin with the same letter.
5332 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5333 Many assorted bugs have been handled. Many more remain to be handled.
5334 See the various ChangeLog files (primarily in gdb and bfd) for details.
5337 *** Changes in GDB-4.3:
5339 * New machines supported (host and target)
5341 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5342 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5343 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5345 * Almost SCO Unix support
5347 We had hoped to support:
5348 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5349 (except for core file support), but we discovered very late in the release
5350 that it has problems with process groups that render gdb unusable. Sorry
5351 about that. I encourage people to fix it and post the fixes.
5353 * Preliminary ELF and DWARF support
5355 GDB can read ELF object files on System V Release 4, and can handle
5356 debugging records for C, in DWARF format, in ELF files. This support
5357 is preliminary. If you bring up GDB on another SVR4 system, please
5358 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5363 GDB now uses the latest `readline' library. One user-visible change
5364 is that two tabs will list possible command completions, which previously
5365 required typing M-? (meta-question mark, or ESC ?).
5369 The `stepi' bug that many of you noticed has been squashed.
5370 Many bugs in C++ have been handled. Many more remain to be handled.
5371 See the various ChangeLog files (primarily in gdb and bfd) for details.
5373 * State of the MIPS world (in case you wondered):
5375 GDB can understand the symbol tables emitted by the compilers
5376 supplied by most vendors of MIPS-based machines, including DEC. These
5377 symbol tables are in a format that essentially nobody else uses.
5379 Some versions of gcc come with an assembler post-processor called
5380 mips-tfile. This program is required if you want to do source-level
5381 debugging of gcc-compiled programs. I believe FSF does not ship
5382 mips-tfile with gcc version 1, but it will eventually come with gcc
5385 Debugging of g++ output remains a problem. g++ version 1.xx does not
5386 really support it at all. (If you're lucky, you should be able to get
5387 line numbers and stack traces to work, but no parameters or local
5388 variables.) With some work it should be possible to improve the
5391 When gcc version 2 is released, you will have somewhat better luck.
5392 However, even then you will get confusing results for inheritance and
5395 We will eventually provide full debugging of g++ output on
5396 DECstations. This will probably involve some kind of stabs-in-ecoff
5397 encapulation, but the details have not been worked out yet.
5400 *** Changes in GDB-4.2:
5402 * Improved configuration
5404 Only one copy of `configure' exists now, and it is not self-modifying.
5405 Porting BFD is simpler.
5409 The `step' and `next' commands now only stop at the first instruction
5410 of a source line. This prevents the multiple stops that used to occur
5411 in switch statements, for-loops, etc. `Step' continues to stop if a
5412 function that has debugging information is called within the line.
5416 Lots of small bugs fixed. More remain.
5418 * New host supported (not target)
5420 Intel 386 PC clone running Mach i386-none-mach
5423 *** Changes in GDB-4.1:
5425 * Multiple source language support
5427 GDB now has internal scaffolding to handle several source languages.
5428 It determines the type of each source file from its filename extension,
5429 and will switch expression parsing and number formatting to match the
5430 language of the function in the currently selected stack frame.
5431 You can also specifically set the language to be used, with
5432 `set language c' or `set language modula-2'.
5436 GDB now has preliminary support for the GNU Modula-2 compiler,
5437 currently under development at the State University of New York at
5438 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5439 continue through the fall of 1991 and into 1992.
5441 Other Modula-2 compilers are currently not supported, and attempting to
5442 debug programs compiled with them will likely result in an error as the
5443 symbol table is read. Feel free to work on it, though!
5445 There are hooks in GDB for strict type checking and range checking,
5446 in the `Modula-2 philosophy', but they do not currently work.
5450 GDB can now write to executable and core files (e.g. patch
5451 a variable's value). You must turn this switch on, specify
5452 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5453 by assigning a new value to a variable. Modifications take
5456 * Automatic SunOS shared library reading
5458 When you run your program, GDB automatically determines where its
5459 shared libraries (if any) have been loaded, and reads their symbols.
5460 The `share' command is no longer needed. This also works when
5461 examining core files.
5465 You can specify the number of lines that the `list' command shows.
5468 * New machines supported (host and target)
5470 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5471 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5472 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5474 * New hosts supported (not targets)
5476 IBM RT/PC: romp-ibm-aix or rtpc
5478 * New targets supported (not hosts)
5480 AMD 29000 embedded with COFF a29k-none-coff
5481 AMD 29000 embedded with a.out a29k-none-aout
5482 Ultracomputer remote kernel debug a29k-nyu-kern
5484 * New remote interfaces
5490 *** Changes in GDB-4.0:
5494 Wide output is wrapped at good places to make the output more readable.
5496 Gdb now supports cross-debugging from a host machine of one type to a
5497 target machine of another type. Communication with the target system
5498 is over serial lines. The ``target'' command handles connecting to the
5499 remote system; the ``load'' command will download a program into the
5500 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5501 also supports debugging of realtime processes running under VxWorks,
5502 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5503 stub on the target system.
5505 New CPUs supported include the AMD 29000 and Intel 960.
5507 GDB now reads object files and symbol tables via a ``binary file''
5508 library, which allows a single copy of GDB to debug programs of multiple
5509 object file types such as a.out and coff.
5511 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5512 refcard.dvi and refcard.ps are available to format it).
5515 * Control-Variable user interface simplified
5517 All variables that control the operation of the debugger can be set
5518 by the ``set'' command, and displayed by the ``show'' command.
5520 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5521 ``Show prompt'' produces the response:
5522 Gdb's prompt is new-gdb=>.
5524 What follows are the NEW set commands. The command ``help set'' will
5525 print a complete list of old and new set commands. ``help set FOO''
5526 will give a longer description of the variable FOO. ``show'' will show
5527 all of the variable descriptions and their current settings.
5529 confirm on/off: Enables warning questions for operations that are
5530 hard to recover from, e.g. rerunning the program while
5531 it is already running. Default is ON.
5533 editing on/off: Enables EMACS style command line editing
5534 of input. Previous lines can be recalled with
5535 control-P, the current line can be edited with control-B,
5536 you can search for commands with control-R, etc.
5539 history filename NAME: NAME is where the gdb command history
5540 will be stored. The default is .gdb_history,
5541 or the value of the environment variable
5544 history size N: The size, in commands, of the command history. The
5545 default is 256, or the value of the environment variable
5548 history save on/off: If this value is set to ON, the history file will
5549 be saved after exiting gdb. If set to OFF, the
5550 file will not be saved. The default is OFF.
5552 history expansion on/off: If this value is set to ON, then csh-like
5553 history expansion will be performed on
5554 command line input. The default is OFF.
5556 radix N: Sets the default radix for input and output. It can be set
5557 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5558 in the current radix, so "set radix 10" is always a no-op.
5560 height N: This integer value is the number of lines on a page. Default
5561 is 24, the current `stty rows'' setting, or the ``li#''
5562 setting from the termcap entry matching the environment
5565 width N: This integer value is the number of characters on a line.
5566 Default is 80, the current `stty cols'' setting, or the ``co#''
5567 setting from the termcap entry matching the environment
5570 Note: ``set screensize'' is obsolete. Use ``set height'' and
5571 ``set width'' instead.
5573 print address on/off: Print memory addresses in various command displays,
5574 such as stack traces and structure values. Gdb looks
5575 more ``symbolic'' if you turn this off; it looks more
5576 ``machine level'' with it on. Default is ON.
5578 print array on/off: Prettyprint arrays. New convenient format! Default
5581 print demangle on/off: Print C++ symbols in "source" form if on,
5584 print asm-demangle on/off: Same, for assembler level printouts
5587 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5590 * Support for Epoch Environment.
5592 The epoch environment is a version of Emacs v18 with windowing. One
5593 new command, ``inspect'', is identical to ``print'', except that if you
5594 are running in the epoch environment, the value is printed in its own
5598 * Support for Shared Libraries
5600 GDB can now debug programs and core files that use SunOS shared libraries.
5601 Symbols from a shared library cannot be referenced
5602 before the shared library has been linked with the program (this
5603 happens after you type ``run'' and before the function main() is entered).
5604 At any time after this linking (including when examining core files
5605 from dynamically linked programs), gdb reads the symbols from each
5606 shared library when you type the ``sharedlibrary'' command.
5607 It can be abbreviated ``share''.
5609 sharedlibrary REGEXP: Load shared object library symbols for files
5610 matching a unix regular expression. No argument
5611 indicates to load symbols for all shared libraries.
5613 info sharedlibrary: Status of loaded shared libraries.
5618 A watchpoint stops execution of a program whenever the value of an
5619 expression changes. Checking for this slows down execution
5620 tremendously whenever you are in the scope of the expression, but is
5621 quite useful for catching tough ``bit-spreader'' or pointer misuse
5622 problems. Some machines such as the 386 have hardware for doing this
5623 more quickly, and future versions of gdb will use this hardware.
5625 watch EXP: Set a watchpoint (breakpoint) for an expression.
5627 info watchpoints: Information about your watchpoints.
5629 delete N: Deletes watchpoint number N (same as breakpoints).
5630 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5631 enable N: Re-enables watchpoint number N (same as breakpoints).
5634 * C++ multiple inheritance
5636 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5639 * C++ exception handling
5641 Gdb now supports limited C++ exception handling. Besides the existing
5642 ability to breakpoint on an exception handler, gdb can breakpoint on
5643 the raising of an exception (before the stack is peeled back to the
5646 catch FOO: If there is a FOO exception handler in the dynamic scope,
5647 set a breakpoint to catch exceptions which may be raised there.
5648 Multiple exceptions (``catch foo bar baz'') may be caught.
5650 info catch: Lists all exceptions which may be caught in the
5651 current stack frame.
5654 * Minor command changes
5656 The command ``call func (arg, arg, ...)'' now acts like the print
5657 command, except it does not print or save a value if the function's result
5658 is void. This is similar to dbx usage.
5660 The ``up'' and ``down'' commands now always print the frame they end up
5661 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5662 frames without printing.
5664 * New directory command
5666 'dir' now adds directories to the FRONT of the source search path.
5667 The path starts off empty. Source files that contain debug information
5668 about the directory in which they were compiled can be found even
5669 with an empty path; Sun CC and GCC include this information. If GDB can't
5670 find your source file in the current directory, type "dir .".
5672 * Configuring GDB for compilation
5674 For normal use, type ``./configure host''. See README or gdb.texinfo
5677 GDB now handles cross debugging. If you are remotely debugging between
5678 two different machines, type ``./configure host -target=targ''.
5679 Host is the machine where GDB will run; targ is the machine
5680 where the program that you are debugging will run.
5682 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.