1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.7
6 * GDB supports printing and modifying of variable length automatic arrays
7 as specified in ISO C99.
9 * The ARM simulator now supports instruction level tracing
10 with or without disassembly.
14 GDB now has support for scripting using Guile. Whether this is
15 available is determined at configure time.
16 Guile version 2.0 or greater is required.
17 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
19 * New commands (for set/show, see "New options" below)
23 Invoke CODE by passing it to the Guile interpreter.
27 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
29 info auto-load guile-scripts [regexp]
30 Print the list of automatically loaded Guile scripts.
32 * The source command is now capable of sourcing Guile scripts.
33 This feature is dependent on the debugger being built with Guile support.
37 set print symbol-loading (off|brief|full)
38 show print symbol-loading
39 Control whether to print informational messages when loading symbol
40 information for a file. The default is "full", but when debugging
41 programs with large numbers of shared libraries the amount of output
44 set guile print-stack (none|message|full)
45 show guile print-stack
46 Show a stack trace when an error is encountered in a Guile script.
48 set auto-load guile-scripts (on|off)
49 show auto-load guile-scripts
50 Control auto-loading of Guile script files.
52 maint ada set ignore-descriptive-types (on|off)
53 maint ada show ignore-descriptive-types
54 Control whether the debugger should ignore descriptive types in Ada
55 programs. The default is not to ignore the descriptive types. See
56 the user manual for more details on descriptive types and the intended
59 * New features in the GDB remote stub, GDBserver
61 ** New option --debug-format=option1[,option2,...] allows one to add
62 additional text to each output. At present only timestamps
63 are supported: --debug-format=timestamps.
64 Timestamps can also be turned on with the
65 "monitor set debug-format timestamps" command from GDB.
67 * The 'record instruction-history' command now starts counting instructions
68 at one. This also affects the instruction ranges reported by the
69 'record function-call-history' command when given the /i modifier.
71 * The command 'record function-call-history' supports a new modifier '/c' to
72 indent the function names based on their call stack depth.
73 The fields for the '/i' and '/l' modifier have been reordered.
74 The source line range is now prefixed with 'at'.
75 The instruction range is now prefixed with 'inst'.
76 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
77 "record instruction-history" and "list" commands.
79 * The ranges given as arguments to the 'record function-call-history' and
80 'record instruction-history' commands are now inclusive.
82 * The btrace record target now supports the 'record goto' command.
83 For locations inside the execution trace, the back trace is computed
84 based on the information stored in the execution trace.
86 * The btrace record target supports limited reverse execution and replay.
87 The target does not record data and therefore does not allow reading
90 * The "catch syscall" command now works on s390*-linux* targets.
94 qXfer:btrace:read's annex
95 The qXfer:btrace:read packet supports a new annex 'delta' to read
96 branch trace incrementally.
100 ** Valid Python operations on gdb.Value objects representing
101 structs/classes invoke the corresponding overloaded operators if
105 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
107 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
108 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
109 its alias "share", instead.
111 *** Changes in GDB 7.7
113 * Improved support for process record-replay and reverse debugging on
114 arm*-linux* targets. Support for thumb32 and syscall instruction
115 recording has been added.
117 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
119 * GDB now supports Fission DWP file format version 2.
120 http://gcc.gnu.org/wiki/DebugFission
122 * New convenience function "$_isvoid", to check whether an expression
123 is void. A void expression is an expression where the type of the
124 result is "void". For example, some convenience variables may be
125 "void" when evaluated (e.g., "$_exitcode" before the execution of
126 the program being debugged; or an undefined convenience variable).
127 Another example, when calling a function whose return type is
130 * The "maintenance print objfiles" command now takes an optional regexp.
132 * The "catch syscall" command now works on arm*-linux* targets.
134 * GDB now consistently shows "<not saved>" when printing values of
135 registers the debug info indicates have not been saved in the frame
136 and there's nowhere to retrieve them from
137 (callee-saved/call-clobbered registers):
142 (gdb) info registers rax
145 Before, the former would print "<optimized out>", and the latter
146 "*value not available*".
148 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
153 ** Frame filters and frame decorators have been added.
154 ** Temporary breakpoints are now supported.
155 ** Line tables representation has been added.
156 ** New attribute 'parent_type' for gdb.Field objects.
157 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
158 ** New attribute 'name' for gdb.Type objects.
162 Nios II ELF nios2*-*-elf
163 Nios II GNU/Linux nios2*-*-linux
164 Texas Instruments MSP430 msp430*-*-elf
166 * Removed native configurations
168 Support for these a.out NetBSD and OpenBSD obsolete configurations has
169 been removed. ELF variants of these configurations are kept supported.
171 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
172 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
173 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
174 i[34567]86-*-openbsd3.[0-3]
175 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
176 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
177 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
181 Like "catch throw", but catches a re-thrown exception.
183 Renamed from old "maint check-symtabs".
185 Perform consistency checks on symtabs.
187 Expand symtabs matching an optional regexp.
190 Display the details of GDB configure-time options.
192 maint set|show per-command
193 maint set|show per-command space
194 maint set|show per-command time
195 maint set|show per-command symtab
196 Enable display of per-command gdb resource usage.
198 remove-symbol-file FILENAME
199 remove-symbol-file -a ADDRESS
200 Remove a symbol file added via add-symbol-file. The file to remove
201 can be identified by its filename or by an address that lies within
202 the boundaries of this symbol file in memory.
205 info exceptions REGEXP
206 Display the list of Ada exceptions defined in the program being
207 debugged. If provided, only the exceptions whose names match REGEXP
212 set debug symfile off|on
214 Control display of debugging info regarding reading symbol files and
215 symbol tables within those files
217 set print raw frame-arguments
218 show print raw frame-arguments
219 Set/show whether to print frame arguments in raw mode,
220 disregarding any defined pretty-printers.
222 set remote trace-status-packet
223 show remote trace-status-packet
224 Set/show the use of remote protocol qTStatus packet.
228 Control display of debugging messages related to Nios II targets.
232 Control whether target-assisted range stepping is enabled.
234 set startup-with-shell
235 show startup-with-shell
236 Specifies whether Unix child processes are started via a shell or
241 Use the target memory cache for accesses to the code segment. This
242 improves performance of remote debugging (particularly disassembly).
244 * You can now use a literal value 'unlimited' for options that
245 interpret 0 or -1 as meaning "unlimited". E.g., "set
246 trace-buffer-size unlimited" is now an alias for "set
247 trace-buffer-size -1" and "set height unlimited" is now an alias for
250 * The "set debug symtab-create" debugging option of GDB has been changed to
251 accept a verbosity level. 0 means "off", 1 provides basic debugging
252 output, and values of 2 or greater provides more verbose output.
254 * New command-line options
256 Display the details of GDB configure-time options.
258 * The command 'tsave' can now support new option '-ctf' to save trace
259 buffer in Common Trace Format.
261 * Newly installed $prefix/bin/gcore acts as a shell interface for the
264 * GDB now implements the the C++ 'typeid' operator.
266 * The new convenience variable $_exception holds the exception being
267 thrown or caught at an exception-related catchpoint.
269 * The exception-related catchpoints, like "catch throw", now accept a
270 regular expression which can be used to filter exceptions by type.
272 * The new convenience variable $_exitsignal is automatically set to
273 the terminating signal number when the program being debugged dies
274 due to an uncaught signal.
278 ** All MI commands now accept an optional "--language" option.
279 Support for this feature can be verified by using the "-list-features"
280 command, which should contain "language-option".
282 ** The new command -info-gdb-mi-command allows the user to determine
283 whether a GDB/MI command is supported or not.
285 ** The "^error" result record returned when trying to execute an undefined
286 GDB/MI command now provides a variable named "code" whose content is the
287 "undefined-command" error code. Support for this feature can be verified
288 by using the "-list-features" command, which should contain
289 "undefined-command-error-code".
291 ** The -trace-save MI command can optionally save trace buffer in Common
294 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
296 ** The command -data-list-register-values now accepts an optional
297 "--skip-unavailable" option. When used, only the available registers
300 ** The new command -trace-frame-collected dumps collected variables,
301 computed expressions, tvars, memory and registers in a traceframe.
303 ** The commands -stack-list-locals, -stack-list-arguments and
304 -stack-list-variables now accept an option "--skip-unavailable".
305 When used, only the available locals or arguments are displayed.
307 ** The -exec-run command now accepts an optional "--start" option.
308 When used, the command follows the same semantics as the "start"
309 command, stopping the program's execution at the start of its
310 main subprogram. Support for this feature can be verified using
311 the "-list-features" command, which should contain
312 "exec-run-start-option".
314 ** The new commands -catch-assert and -catch-exceptions insert
315 catchpoints stopping the program when Ada exceptions are raised.
317 ** The new command -info-ada-exceptions provides the equivalent of
318 the new "info exceptions" command.
320 * New system-wide configuration scripts
321 A GDB installation now provides scripts suitable for use as system-wide
322 configuration scripts for the following systems:
326 * GDB now supports target-assigned range stepping with remote targets.
327 This improves the performance of stepping source lines by reducing
328 the number of control packets from/to GDB. See "New remote packets"
331 * GDB now understands the element 'tvar' in the XML traceframe info.
332 It has the id of the collected trace state variables.
334 * On S/390 targets that provide the transactional-execution feature,
335 the program interruption transaction diagnostic block (TDB) is now
336 represented as a number of additional "registers" in GDB.
342 The vCont packet supports a new 'r' action, that tells the remote
343 stub to step through an address range itself, without GDB
344 involvemement at each single-step.
346 qXfer:libraries-svr4:read's annex
347 The previously unused annex of the qXfer:libraries-svr4:read packet
348 is now used to support passing an argument list. The remote stub
349 reports support for this argument list to GDB's qSupported query.
350 The defined arguments are "start" and "prev", used to reduce work
351 necessary for library list updating, resulting in significant
354 * New features in the GDB remote stub, GDBserver
356 ** GDBserver now supports target-assisted range stepping. Currently
357 enabled on x86/x86_64 GNU/Linux targets.
359 ** GDBserver now adds element 'tvar' in the XML in the reply to
360 'qXfer:traceframe-info:read'. It has the id of the collected
361 trace state variables.
363 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
366 * New 'z' formatter for printing and examining memory, this displays the
367 value as hexadecimal zero padded on the left to the size of the type.
369 * GDB can now use Windows x64 unwinding data.
371 * The "set remotebaud" command has been replaced by "set serial baud".
372 Similarly, "show remotebaud" has been replaced by "show serial baud".
373 The "set remotebaud" and "show remotebaud" commands are still available
374 to provide backward compatibility with older versions of GDB.
376 *** Changes in GDB 7.6
378 * Target record has been renamed to record-full.
379 Record/replay is now enabled with the "record full" command.
380 This also affects settings that are associated with full record/replay
381 that have been moved from "set/show record" to "set/show record full":
383 set|show record full insn-number-max
384 set|show record full stop-at-limit
385 set|show record full memory-query
387 * A new record target "record-btrace" has been added. The new target
388 uses hardware support to record the control-flow of a process. It
389 does not support replaying the execution, but it implements the
390 below new commands for investigating the recorded execution log.
391 This new recording method can be enabled using:
395 The "record-btrace" target is only available on Intel Atom processors
396 and requires a Linux kernel 2.6.32 or later.
398 * Two new commands have been added for record/replay to give information
399 about the recorded execution without having to replay the execution.
400 The commands are only supported by "record btrace".
402 record instruction-history prints the execution history at
403 instruction granularity
405 record function-call-history prints the execution history at
408 * New native configurations
410 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
411 FreeBSD/powerpc powerpc*-*-freebsd
412 x86_64/Cygwin x86_64-*-cygwin*
413 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
417 ARM AArch64 aarch64*-*-elf
418 ARM AArch64 GNU/Linux aarch64*-*-linux
419 Lynx 178 PowerPC powerpc-*-lynx*178
420 x86_64/Cygwin x86_64-*-cygwin*
421 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
423 * If the configured location of system.gdbinit file (as given by the
424 --with-system-gdbinit option at configure time) is in the
425 data-directory (as specified by --with-gdb-datadir at configure
426 time) or in one of its subdirectories, then GDB will look for the
427 system-wide init file in the directory specified by the
428 --data-directory command-line option.
430 * New command line options:
432 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
433 other initialization files, unlike -nx which disables all of them.
435 * Removed command line options
437 -epoch This was used by the gdb mode in Epoch, an ancient fork of
440 * The 'ptype' and 'whatis' commands now accept an argument to control
443 * 'info proc' now works on some core files.
447 ** Vectors can be created with gdb.Type.vector.
449 ** Python's atexit.register now works in GDB.
451 ** Types can be pretty-printed via a Python API.
453 ** Python 3 is now supported (in addition to Python 2.4 or later)
455 ** New class gdb.Architecture exposes GDB's internal representation
456 of architecture in the Python API.
458 ** New method Frame.architecture returns the gdb.Architecture object
459 corresponding to the frame's architecture.
461 * New Python-based convenience functions:
463 ** $_memeq(buf1, buf2, length)
464 ** $_streq(str1, str2)
466 ** $_regex(str, regex)
468 * The 'cd' command now defaults to using '~' (the home directory) if not
471 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
472 default for GCC since November 2000.
474 * The command 'forward-search' can now be abbreviated as 'fo'.
476 * The command 'info tracepoints' can now display 'installed on target'
477 or 'not installed on target' for each non-pending location of tracepoint.
479 * New configure options
481 --enable-libmcheck/--disable-libmcheck
482 By default, development versions are built with -lmcheck on hosts
483 that support it, in order to help track memory corruption issues.
484 Release versions, on the other hand, are built without -lmcheck
485 by default. The --enable-libmcheck/--disable-libmcheck configure
486 options allow the user to override that default.
487 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
488 This configure option allows the user to build GDB with
489 libbabeltrace using which GDB can read Common Trace Format data.
491 * New commands (for set/show, see "New options" below)
494 Catch signals. This is similar to "handle", but allows commands and
495 conditions to be attached.
498 List the BFDs known to GDB.
500 python-interactive [command]
502 Start a Python interactive prompt, or evaluate the optional command
503 and print the result of expressions.
506 "py" is a new alias for "python".
508 enable type-printer [name]...
509 disable type-printer [name]...
510 Enable or disable type printers.
514 ** For the Renesas Super-H architecture, the "regs" command has been removed
515 (has been deprecated in GDB 7.5), and "info all-registers" should be used
520 set print type methods (on|off)
521 show print type methods
522 Control whether method declarations are displayed by "ptype".
523 The default is to show them.
525 set print type typedefs (on|off)
526 show print type typedefs
527 Control whether typedef definitions are displayed by "ptype".
528 The default is to show them.
530 set filename-display basename|relative|absolute
531 show filename-display
532 Control the way in which filenames is displayed.
533 The default is "relative", which preserves previous behavior.
535 set trace-buffer-size
536 show trace-buffer-size
537 Request target to change the size of trace buffer.
539 set remote trace-buffer-size-packet auto|on|off
540 show remote trace-buffer-size-packet
541 Control the use of the remote protocol `QTBuffer:size' packet.
545 Control display of debugging messages related to ARM AArch64.
548 set debug coff-pe-read
549 show debug coff-pe-read
550 Control display of debugging messages related to reading of COFF/PE
555 Control display of debugging messages related to Mach-O symbols
558 set debug notification
559 show debug notification
560 Control display of debugging info for async remote notification.
564 ** Command parameter changes are now notified using new async record
565 "=cmd-param-changed".
566 ** Trace frame changes caused by command "tfind" are now notified using
567 new async record "=traceframe-changed".
568 ** The creation, deletion and modification of trace state variables
569 are now notified using new async records "=tsv-created",
570 "=tsv-deleted" and "=tsv-modified".
571 ** The start and stop of process record are now notified using new
572 async record "=record-started" and "=record-stopped".
573 ** Memory changes are now notified using new async record
575 ** The data-disassemble command response will include a "fullname" field
576 containing the absolute file name when source has been requested.
577 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
578 command, to allow pattern filling of memory areas.
579 ** New commands "-catch-load"/"-catch-unload" added for intercepting
580 library load/unload events.
581 ** The response to breakpoint commands and breakpoint async records
582 includes an "installed" field containing a boolean state about each
583 non-pending tracepoint location is whether installed on target or not.
584 ** Output of the "-trace-status" command includes a "trace-file" field
585 containing the name of the trace file being examined. This field is
586 optional, and only present when examining a trace file.
587 ** The "fullname" field is now always present along with the "file" field,
588 even if the file cannot be found by GDB.
590 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
591 You must have the LZMA library available when configuring GDB for this
592 feature to be enabled. For more information, see:
593 http://fedoraproject.org/wiki/Features/MiniDebugInfo
598 Set the size of trace buffer. The remote stub reports support for this
599 packet to gdb's qSupported query.
602 Enable Branch Trace Store (BTS)-based branch tracing for the current
603 thread. The remote stub reports support for this packet to gdb's
607 Disable branch tracing for the current thread. The remote stub reports
608 support for this packet to gdb's qSupported query.
611 Read the traced branches for the current thread. The remote stub
612 reports support for this packet to gdb's qSupported query.
614 *** Changes in GDB 7.5
616 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
617 for more x32 ABI info.
619 * GDB now supports access to MIPS DSP registers on Linux targets.
621 * GDB now supports debugging microMIPS binaries.
623 * The "info os" command on GNU/Linux can now display information on
624 several new classes of objects managed by the operating system:
625 "info os procgroups" lists process groups
626 "info os files" lists file descriptors
627 "info os sockets" lists internet-domain sockets
628 "info os shm" lists shared-memory regions
629 "info os semaphores" lists semaphores
630 "info os msg" lists message queues
631 "info os modules" lists loaded kernel modules
633 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
634 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
635 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
636 options and inspect the probe arguments using the new $_probe_arg family
637 of convenience variables. You can obtain more information about SystemTap
638 in <http://sourceware.org/systemtap/>.
640 * GDB now supports reversible debugging on ARM, it allows you to
641 debug basic ARM and THUMB instructions, and provides
642 record/replay support.
644 * The option "symbol-reloading" has been deleted as it is no longer used.
648 ** GDB commands implemented in Python can now be put in command class
651 ** The "maint set python print-stack on|off" is now deleted.
653 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
654 apply "flag enum"-style pretty-printing to any enum.
656 ** gdb.lookup_symbol can now work when there is no current frame.
658 ** gdb.Symbol now has a 'line' attribute, holding the line number in
659 the source at which the symbol was defined.
661 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
662 method 'value'. The former indicates whether the symbol needs a
663 frame in order to compute its value, and the latter computes the
666 ** A new method 'referenced_value' on gdb.Value objects which can
667 dereference pointer as well as C++ reference values.
669 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
670 which return the global and static blocks (as gdb.Block objects),
671 of the underlying symbol table, respectively.
673 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
674 object associated with a PC value.
676 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
677 of the address range occupied by code for the current source line.
679 * Go language support.
680 GDB now supports debugging programs written in the Go programming
683 * GDBserver now supports stdio connections.
684 E.g. (gdb) target remote | ssh myhost gdbserver - hello
686 * The binary "gdbtui" can no longer be built or installed.
687 Use "gdb -tui" instead.
689 * GDB will now print "flag" enums specially. A flag enum is one where
690 all the enumerator values have no bits in common when pairwise
691 "and"ed. When printing a value whose type is a flag enum, GDB will
692 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
693 (gdb) print (enum E) 3
696 * The filename part of a linespec will now match trailing components
697 of a source file name. For example, "break gcc/expr.c:1000" will
698 now set a breakpoint in build/gcc/expr.c, but not
701 * The "info proc" and "generate-core-file" commands will now also
702 work on remote targets connected to GDBserver on Linux.
704 * The command "info catch" has been removed. It has been disabled
707 * The "catch exception" and "catch assert" commands now accept
708 a condition at the end of the command, much like the "break"
709 command does. For instance:
711 (gdb) catch exception Constraint_Error if Barrier = True
713 Previously, it was possible to add a condition to such catchpoints,
714 but it had to be done as a second step, after the catchpoint had been
715 created, using the "condition" command.
717 * The "info static-tracepoint-marker" command will now also work on
718 native Linux targets with in-process agent.
720 * GDB can now set breakpoints on inlined functions.
722 * The .gdb_index section has been updated to include symbols for
723 inlined functions. GDB will ignore older .gdb_index sections by
724 default, which could cause symbol files to be loaded more slowly
725 until their .gdb_index sections can be recreated. The new command
726 "set use-deprecated-index-sections on" will cause GDB to use any older
727 .gdb_index sections it finds. This will restore performance, but the
728 ability to set breakpoints on inlined functions will be lost in symbol
729 files with older .gdb_index sections.
731 The .gdb_index section has also been updated to record more information
732 about each symbol. This speeds up the "info variables", "info functions"
733 and "info types" commands when used with programs having the .gdb_index
734 section, as well as speeding up debugging with shared libraries using
735 the .gdb_index section.
737 * Ada support for GDB/MI Variable Objects has been added.
739 * GDB can now support 'breakpoint always-inserted mode' in 'record'
744 ** New command -info-os is the MI equivalent of "info os".
746 ** Output logs ("set logging" and related) now include MI output.
750 ** "set use-deprecated-index-sections on|off"
751 "show use-deprecated-index-sections on|off"
752 Controls the use of deprecated .gdb_index sections.
754 ** "catch load" and "catch unload" can be used to stop when a shared
755 library is loaded or unloaded, respectively.
757 ** "enable count" can be used to auto-disable a breakpoint after
760 ** "info vtbl" can be used to show the virtual method tables for
761 C++ and Java objects.
763 ** "explore" and its sub commands "explore value" and "explore type"
764 can be used to recursively explore values and types of
765 expressions. These commands are available only if GDB is
766 configured with '--with-python'.
768 ** "info auto-load" shows status of all kinds of auto-loaded files,
769 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
770 sequences of commands files, "info auto-load python-scripts"
771 shows status of auto-loading Python script files,
772 "info auto-load local-gdbinit" shows status of loading init file
773 (.gdbinit) from current directory and "info auto-load libthread-db" shows
774 status of inferior specific thread debugging shared library loading.
776 ** "info auto-load-scripts", "set auto-load-scripts on|off"
777 and "show auto-load-scripts" commands have been deprecated, use their
778 "info auto-load python-scripts", "set auto-load python-scripts on|off"
779 and "show auto-load python-scripts" counterparts instead.
781 ** "dprintf location,format,args..." creates a dynamic printf, which
782 is basically a breakpoint that does a printf and immediately
783 resumes your program's execution, so it is like a printf that you
784 can insert dynamically at runtime instead of at compiletime.
786 ** "set print symbol"
788 Controls whether GDB attempts to display the symbol, if any,
789 corresponding to addresses it prints. This defaults to "on", but
790 you can set it to "off" to restore GDB's previous behavior.
792 * Deprecated commands
794 ** For the Renesas Super-H architecture, the "regs" command has been
795 deprecated, and "info all-registers" should be used instead.
799 Renesas RL78 rl78-*-elf
800 HP OpenVMS ia64 ia64-hp-openvms*
802 * GDBserver supports evaluation of breakpoint conditions. When
803 support is advertised by GDBserver, GDB may be told to send the
804 breakpoint conditions in bytecode form to GDBserver. GDBserver
805 will only report the breakpoint trigger to GDB when its condition
811 show mips compression
812 Select the compressed ISA encoding used in functions that have no symbol
813 information available. The encoding can be set to either of:
816 and is updated automatically from ELF file flags if available.
818 set breakpoint condition-evaluation
819 show breakpoint condition-evaluation
820 Control whether breakpoint conditions are evaluated by GDB ("host") or by
821 GDBserver ("target"). Default option "auto" chooses the most efficient
823 This option can improve debugger efficiency depending on the speed of the
827 Disable auto-loading globally.
830 Show auto-loading setting of all kinds of auto-loaded files.
832 set auto-load gdb-scripts on|off
833 show auto-load gdb-scripts
834 Control auto-loading of GDB canned sequences of commands files.
836 set auto-load python-scripts on|off
837 show auto-load python-scripts
838 Control auto-loading of Python script files.
840 set auto-load local-gdbinit on|off
841 show auto-load local-gdbinit
842 Control loading of init file (.gdbinit) from current directory.
844 set auto-load libthread-db on|off
845 show auto-load libthread-db
846 Control auto-loading of inferior specific thread debugging shared library.
848 set auto-load scripts-directory <dir1>[:<dir2>...]
849 show auto-load scripts-directory
850 Set a list of directories from which to load auto-loaded scripts.
851 Automatically loaded Python scripts and GDB scripts are located in one
852 of the directories listed by this option.
853 The delimiter (':' above) may differ according to the host platform.
855 set auto-load safe-path <dir1>[:<dir2>...]
856 show auto-load safe-path
857 Set a list of directories from which it is safe to auto-load files.
858 The delimiter (':' above) may differ according to the host platform.
860 set debug auto-load on|off
862 Control display of debugging info for auto-loading the files above.
864 set dprintf-style gdb|call|agent
866 Control the way in which a dynamic printf is performed; "gdb"
867 requests a GDB printf command, while "call" causes dprintf to call a
868 function in the inferior. "agent" requests that the target agent
869 (such as GDBserver) do the printing.
871 set dprintf-function <expr>
872 show dprintf-function
873 set dprintf-channel <expr>
875 Set the function and optional first argument to the call when using
876 the "call" style of dynamic printf.
878 set disconnected-dprintf on|off
879 show disconnected-dprintf
880 Control whether agent-style dynamic printfs continue to be in effect
881 after GDB disconnects.
883 * New configure options
886 Configure default value for the 'set auto-load scripts-directory'
887 setting above. It defaults to '$debugdir:$datadir/auto-load',
888 $debugdir representing global debugging info directories (available
889 via 'show debug-file-directory') and $datadir representing GDB's data
890 directory (available via 'show data-directory').
892 --with-auto-load-safe-path
893 Configure default value for the 'set auto-load safe-path' setting
894 above. It defaults to the --with-auto-load-dir setting.
896 --without-auto-load-safe-path
897 Set 'set auto-load safe-path' to '/', effectively disabling this
902 z0/z1 conditional breakpoints extension
904 The z0/z1 breakpoint insertion packets have been extended to carry
905 a list of conditional expressions over to the remote stub depending on the
906 condition evaluation mode. The use of this extension can be controlled
907 via the "set remote conditional-breakpoints-packet" command.
911 Specify the signals which the remote stub may pass to the debugged
912 program without GDB involvement.
914 * New command line options
916 --init-command=FILE, -ix Like --command, -x but execute it
917 before loading inferior.
918 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
919 execute it before loading inferior.
921 *** Changes in GDB 7.4
923 * GDB now handles ambiguous linespecs more consistently; the existing
924 FILE:LINE support has been expanded to other types of linespecs. A
925 breakpoint will now be set on all matching locations in all
926 inferiors, and locations will be added or removed according to
929 * GDB now allows you to skip uninteresting functions and files when
930 stepping with the "skip function" and "skip file" commands.
932 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
933 and "show remote hardware-watchpoint-length-limit". These allows to
934 set or show the maximum length limit (in bytes) of a remote
935 target hardware watchpoint.
937 This allows e.g. to use "unlimited" hardware watchpoints with the
938 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
939 watchpoints are slower than real hardware watchpoints but are
940 significantly faster than gdb software watchpoints.
944 ** The register_pretty_printer function in module gdb.printing now takes
945 an optional `replace' argument. If True, the new printer replaces any
948 ** The "maint set python print-stack on|off" command has been
949 deprecated and will be deleted in GDB 7.5.
950 A new command: "set python print-stack none|full|message" has
951 replaced it. Additionally, the default for "print-stack" is
952 now "message", which just prints the error message without
955 ** A prompt substitution hook (prompt_hook) is now available to the
958 ** A new Python module, gdb.prompt has been added to the GDB Python
959 modules library. This module provides functionality for
960 escape sequences in prompts (used by set/show
961 extended-prompt). These escape sequences are replaced by their
964 ** Python commands and convenience-functions located in
965 'data-directory'/python/gdb/command and
966 'data-directory'/python/gdb/function are now automatically loaded
969 ** Blocks now provide four new attributes. global_block and
970 static_block will return the global and static blocks
971 respectively. is_static and is_global are boolean attributes
972 that indicate if the block is one of those two types.
974 ** Symbols now provide the "type" attribute, the type of the symbol.
976 ** The "gdb.breakpoint" function has been deprecated in favor of
979 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
980 of a function. This class is based on the "finish" command
981 available in the CLI.
983 ** Type objects for struct and union types now allow access to
984 the fields using standard Python dictionary (mapping) methods.
985 For example, "some_type['myfield']" now works, as does
988 ** A new event "gdb.new_objfile" has been added, triggered by loading a
991 ** A new function, "deep_items" has been added to the gdb.types
992 module in the GDB Python modules library. This function returns
993 an iterator over the fields of a struct or union type. Unlike
994 the standard Python "iteritems" method, it will recursively traverse
995 any anonymous fields.
999 ** "*stopped" events can report several new "reason"s, such as
1002 ** Breakpoint changes are now notified using new async records, like
1003 "=breakpoint-modified".
1005 ** New command -ada-task-info.
1007 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1008 $sdir specifies the default system locations of shared libraries.
1009 $pdir specifies the directory where the libpthread used by the application
1012 GDB no longer looks in $sdir and $pdir after it has searched the directories
1013 mentioned in libthread-db-search-path. If you want to search those
1014 directories, they must be specified in libthread-db-search-path.
1015 The default value of libthread-db-search-path on GNU/Linux and Solaris
1016 systems is now "$sdir:$pdir".
1018 $pdir is not supported by gdbserver, it is currently ignored.
1019 $sdir is supported by gdbserver.
1021 * New configure option --with-iconv-bin.
1022 When using the internationalization support like the one in the GNU C
1023 library, GDB will invoke the "iconv" program to get a list of supported
1024 character sets. If this program lives in a non-standard location, one can
1025 use this option to specify where to find it.
1027 * When natively debugging programs on PowerPC BookE processors running
1028 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1029 watchpoints, which specify a mask in addition to an address to watch.
1030 The mask specifies that some bits of an address (the bits which are
1031 reset in the mask) should be ignored when matching the address accessed
1032 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1033 section in the user manual for more details.
1035 * The new option --once causes GDBserver to stop listening for connections once
1036 the first connection is made. The listening port used by GDBserver will
1037 become available after that.
1039 * New commands "info macros" and "alias" have been added.
1041 * New function parameters suffix @entry specifies value of function parameter
1042 at the time the function got called. Entry values are available only since
1048 "!" is now an alias of the "shell" command.
1049 Note that no space is needed between "!" and SHELL COMMAND.
1053 watch EXPRESSION mask MASK_VALUE
1054 The watch command now supports the mask argument which allows creation
1055 of masked watchpoints, if the current architecture supports this feature.
1057 info auto-load-scripts [REGEXP]
1058 This command was formerly named "maintenance print section-scripts".
1059 It is now generally useful and is no longer a maintenance-only command.
1061 info macro [-all] [--] MACRO
1062 The info macro command has new options `-all' and `--'. The first for
1063 printing all definitions of a macro. The second for explicitly specifying
1064 the end of arguments and the beginning of the macro name in case the macro
1065 name starts with a hyphen.
1067 collect[/s] EXPRESSIONS
1068 The tracepoint collect command now takes an optional modifier "/s"
1069 that directs it to dereference pointer-to-character types and
1070 collect the bytes of memory up to a zero byte. The behavior is
1071 similar to what you see when you use the regular print command on a
1072 string. An optional integer following the "/s" sets a bound on the
1073 number of bytes that will be collected.
1076 The trace start command now interprets any supplied arguments as a
1077 note to be recorded with the trace run, with an effect similar to
1078 setting the variable trace-notes.
1081 The trace stop command now interprets any arguments as a note to be
1082 mentioned along with the tstatus report that the trace was stopped
1083 with a command. The effect is similar to setting the variable
1086 * Tracepoints can now be enabled and disabled at any time after a trace
1087 experiment has been started using the standard "enable" and "disable"
1088 commands. It is now possible to start a trace experiment with no enabled
1089 tracepoints; GDB will display a warning, but will allow the experiment to
1090 begin, assuming that tracepoints will be enabled as needed while the trace
1093 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1094 locations with 4-byte instructions, when they were previously
1095 limited to locations with instructions of 5 bytes or longer.
1099 set debug dwarf2-read
1100 show debug dwarf2-read
1101 Turns on or off display of debugging messages related to reading
1102 DWARF debug info. The default is off.
1104 set debug symtab-create
1105 show debug symtab-create
1106 Turns on or off display of debugging messages related to symbol table
1107 creation. The default is off.
1110 show extended-prompt
1111 Set the GDB prompt, and allow escape sequences to be inserted to
1112 display miscellaneous information (see 'help set extended-prompt'
1113 for the list of sequences). This prompt (and any information
1114 accessed through the escape sequences) is updated every time the
1115 prompt is displayed.
1117 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1118 show print entry-values
1119 Set printing of frame argument values at function entry. In some cases
1120 GDB can determine the value of function argument which was passed by the
1121 function caller, even if the value was modified inside the called function.
1123 set debug entry-values
1124 show debug entry-values
1125 Control display of debugging info for determining frame argument values at
1126 function entry and virtual tail call frames.
1128 set basenames-may-differ
1129 show basenames-may-differ
1130 Set whether a source file may have multiple base names.
1131 (A "base name" is the name of a file with the directory part removed.
1132 Example: The base name of "/home/user/hello.c" is "hello.c".)
1133 If set, GDB will canonicalize file names (e.g., expand symlinks)
1134 before comparing them. Canonicalization is an expensive operation,
1135 but it allows the same file be known by more than one base name.
1136 If not set (the default), all source files are assumed to have just
1137 one base name, and gdb will do file name comparisons more efficiently.
1143 Set a user name and notes for the current and any future trace runs.
1144 This is useful for long-running and/or disconnected traces, to
1145 inform others (or yourself) as to who is running the trace, supply
1146 contact information, or otherwise explain what is going on.
1148 set trace-stop-notes
1149 show trace-stop-notes
1150 Set a note attached to the trace run, that is displayed when the
1151 trace has been stopped by a tstop command. This is useful for
1152 instance as an explanation, if you are stopping a trace run that was
1153 started by someone else.
1155 * New remote packets
1159 Dynamically enable a tracepoint in a started trace experiment.
1163 Dynamically disable a tracepoint in a started trace experiment.
1167 Set the user and notes of the trace run.
1171 Query the current status of a tracepoint.
1175 Query the minimum length of instruction at which a fast tracepoint may
1178 * Dcache size (number of lines) and line-size are now runtime-configurable
1179 via "set dcache line" and "set dcache line-size" commands.
1183 Texas Instruments TMS320C6x tic6x-*-*
1187 Renesas RL78 rl78-*-elf
1189 *** Changes in GDB 7.3.1
1191 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1193 *** Changes in GDB 7.3
1195 * GDB has a new command: "thread find [REGEXP]".
1196 It finds the thread id whose name, target id, or thread extra info
1197 matches the given regular expression.
1199 * The "catch syscall" command now works on mips*-linux* targets.
1201 * The -data-disassemble MI command now supports modes 2 and 3 for
1202 dumping the instruction opcodes.
1204 * New command line options
1206 -data-directory DIR Specify DIR as the "data-directory".
1207 This is mostly for testing purposes.
1209 * The "maint set python auto-load on|off" command has been renamed to
1210 "set auto-load-scripts on|off".
1212 * GDB has a new command: "set directories".
1213 It is like the "dir" command except that it replaces the
1214 source path list instead of augmenting it.
1216 * GDB now understands thread names.
1218 On GNU/Linux, "info threads" will display the thread name as set by
1219 prctl or pthread_setname_np.
1221 There is also a new command, "thread name", which can be used to
1222 assign a name internally for GDB to display.
1225 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1226 has been integrated into GDB.
1230 ** The function gdb.Write now accepts an optional keyword 'stream'.
1231 This keyword, when provided, will direct the output to either
1232 stdout, stderr, or GDB's logging output.
1234 ** Parameters can now be be sub-classed in Python, and in particular
1235 you may implement the get_set_doc and get_show_doc functions.
1236 This improves how Parameter set/show documentation is processed
1237 and allows for more dynamic content.
1239 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1240 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1241 have an is_valid method.
1243 ** Breakpoints can now be sub-classed in Python, and in particular
1244 you may implement a 'stop' function that is executed each time
1245 the inferior reaches that breakpoint.
1247 ** New function gdb.lookup_global_symbol looks up a global symbol.
1249 ** GDB values in Python are now callable if the value represents a
1250 function. For example, if 'some_value' represents a function that
1251 takes two integer parameters and returns a value, you can call
1252 that function like so:
1254 result = some_value (10,20)
1256 ** Module gdb.types has been added.
1257 It contains a collection of utilities for working with gdb.Types objects:
1258 get_basic_type, has_field, make_enum_dict.
1260 ** Module gdb.printing has been added.
1261 It contains utilities for writing and registering pretty-printers.
1262 New classes: PrettyPrinter, SubPrettyPrinter,
1263 RegexpCollectionPrettyPrinter.
1264 New function: register_pretty_printer.
1266 ** New commands "info pretty-printers", "enable pretty-printer" and
1267 "disable pretty-printer" have been added.
1269 ** gdb.parameter("directories") is now available.
1271 ** New function gdb.newest_frame returns the newest frame in the
1274 ** The gdb.InferiorThread class has a new "name" attribute. This
1275 holds the thread's name.
1277 ** Python Support for Inferior events.
1278 Python scripts can add observers to be notified of events
1279 occurring in the process being debugged.
1280 The following events are currently supported:
1281 - gdb.events.cont Continue event.
1282 - gdb.events.exited Inferior exited event.
1283 - gdb.events.stop Signal received, and Breakpoint hit events.
1287 ** GDB now puts template parameters in scope when debugging in an
1288 instantiation. For example, if you have:
1290 template<int X> int func (void) { return X; }
1292 then if you step into func<5>, "print X" will show "5". This
1293 feature requires proper debuginfo support from the compiler; it
1294 was added to GCC 4.5.
1296 ** The motion commands "next", "finish", "until", and "advance" now
1297 work better when exceptions are thrown. In particular, GDB will
1298 no longer lose control of the inferior; instead, the GDB will
1299 stop the inferior at the point at which the exception is caught.
1300 This functionality requires a change in the exception handling
1301 code that was introduced in GCC 4.5.
1303 * GDB now follows GCC's rules on accessing volatile objects when
1304 reading or writing target state during expression evaluation.
1305 One notable difference to prior behavior is that "print x = 0"
1306 no longer generates a read of x; the value of the assignment is
1307 now always taken directly from the value being assigned.
1309 * GDB now has some support for using labels in the program's source in
1310 linespecs. For instance, you can use "advance label" to continue
1311 execution to a label.
1313 * GDB now has support for reading and writing a new .gdb_index
1314 section. This section holds a fast index of DWARF debugging
1315 information and can be used to greatly speed up GDB startup and
1316 operation. See the documentation for `save gdb-index' for details.
1318 * The "watch" command now accepts an optional "-location" argument.
1319 When used, this causes GDB to watch the memory referred to by the
1320 expression. Such a watchpoint is never deleted due to it going out
1323 * GDB now supports thread debugging of core dumps on GNU/Linux.
1325 GDB now activates thread debugging using the libthread_db library
1326 when debugging GNU/Linux core dumps, similarly to when debugging
1327 live processes. As a result, when debugging a core dump file, GDB
1328 is now able to display pthread_t ids of threads. For example, "info
1329 threads" shows the same output as when debugging the process when it
1330 was live. In earlier releases, you'd see something like this:
1333 * 1 LWP 6780 main () at main.c:10
1335 While now you see this:
1338 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1340 It is also now possible to inspect TLS variables when debugging core
1343 When debugging a core dump generated on a machine other than the one
1344 used to run GDB, you may need to point GDB at the correct
1345 libthread_db library with the "set libthread-db-search-path"
1346 command. See the user manual for more details on this command.
1348 * When natively debugging programs on PowerPC BookE processors running
1349 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1350 which stop execution of the inferior whenever it executes an instruction
1351 at any address within the specified range. See the "PowerPC Embedded"
1352 section in the user manual for more details.
1354 * New features in the GDB remote stub, GDBserver
1356 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1357 and i686 LynxOS (version 5.x).
1359 ** GDBserver is now supported on Blackfin Linux.
1361 * New native configurations
1363 ia64 HP-UX ia64-*-hpux*
1367 Analog Devices, Inc. Blackfin Processor bfin-*
1369 * Ada task switching is now supported on sparc-elf targets when
1370 debugging a program using the Ravenscar Profile. For more information,
1371 see the "Tasking Support when using the Ravenscar Profile" section
1372 in the GDB user manual.
1374 * Guile support was removed.
1376 * New features in the GNU simulator
1378 ** The --map-info flag lists all known core mappings.
1380 ** CFI flashes may be simulated via the "cfi" device.
1382 *** Changes in GDB 7.2
1384 * Shared library support for remote targets by default
1386 When GDB is configured for a generic, non-OS specific target, like
1387 for example, --target=arm-eabi or one of the many *-*-elf targets,
1388 GDB now queries remote stubs for loaded shared libraries using the
1389 `qXfer:libraries:read' packet. Previously, shared library support
1390 was always disabled for such configurations.
1394 ** Argument Dependent Lookup (ADL)
1396 In C++ ADL lookup directs function search to the namespaces of its
1397 arguments even if the namespace has not been imported.
1407 Here the compiler will search for `foo' in the namespace of 'b'
1408 and find A::foo. GDB now supports this. This construct is commonly
1409 used in the Standard Template Library for operators.
1411 ** Improved User Defined Operator Support
1413 In addition to member operators, GDB now supports lookup of operators
1414 defined in a namespace and imported with a `using' directive, operators
1415 defined in the global scope, operators imported implicitly from an
1416 anonymous namespace, and the ADL operators mentioned in the previous
1418 GDB now also supports proper overload resolution for all the previously
1419 mentioned flavors of operators.
1421 ** static const class members
1423 Printing of static const class members that are initialized in the
1424 class definition has been fixed.
1426 * Windows Thread Information Block access.
1428 On Windows targets, GDB now supports displaying the Windows Thread
1429 Information Block (TIB) structure. This structure is visible either
1430 by using the new command `info w32 thread-information-block' or, by
1431 dereferencing the new convenience variable named `$_tlb', a
1432 thread-specific pointer to the TIB. This feature is also supported
1433 when remote debugging using GDBserver.
1435 * Static tracepoints
1437 Static tracepoints are calls in the user program into a tracing
1438 library. One such library is a port of the LTTng kernel tracer to
1439 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1440 When debugging with GDBserver, GDB now supports combining the GDB
1441 tracepoint machinery with such libraries. For example: the user can
1442 use GDB to probe a static tracepoint marker (a call from the user
1443 program into the tracing library) with the new "strace" command (see
1444 "New commands" below). This creates a "static tracepoint" in the
1445 breakpoint list, that can be manipulated with the same feature set
1446 as fast and regular tracepoints. E.g., collect registers, local and
1447 global variables, collect trace state variables, and define
1448 tracepoint conditions. In addition, the user can collect extra
1449 static tracepoint marker specific data, by collecting the new
1450 $_sdata internal variable. When analyzing the trace buffer, you can
1451 inspect $_sdata like any other variable available to GDB. For more
1452 information, see the "Tracepoints" chapter in GDB user manual. New
1453 remote packets have been defined to support static tracepoints, see
1454 the "New remote packets" section below.
1456 * Better reconstruction of tracepoints after disconnected tracing
1458 GDB will attempt to download the original source form of tracepoint
1459 definitions when starting a trace run, and then will upload these
1460 upon reconnection to the target, resulting in a more accurate
1461 reconstruction of the tracepoints that are in use on the target.
1465 You can now exercise direct control over the ways that GDB can
1466 affect your program. For instance, you can disallow the setting of
1467 breakpoints, so that the program can run continuously (assuming
1468 non-stop mode). In addition, the "observer" variable is available
1469 to switch all of the different controls; in observer mode, GDB
1470 cannot affect the target's behavior at all, which is useful for
1471 tasks like diagnosing live systems in the field.
1473 * The new convenience variable $_thread holds the number of the
1476 * New remote packets
1480 Return the address of the Windows Thread Information Block of a given thread.
1484 In response to several of the tracepoint packets, the target may now
1485 also respond with a number of intermediate `qRelocInsn' request
1486 packets before the final result packet, to have GDB handle
1487 relocating an instruction to execute at a different address. This
1488 is particularly useful for stubs that support fast tracepoints. GDB
1489 reports support for this feature in the qSupported packet.
1493 List static tracepoint markers in the target program.
1497 List static tracepoint markers at a given address in the target
1500 qXfer:statictrace:read
1502 Read the static trace data collected (by a `collect $_sdata'
1503 tracepoint action). The remote stub reports support for this packet
1504 to gdb's qSupported query.
1508 Send the current settings of GDB's permission flags.
1512 Send part of the source (textual) form of a tracepoint definition,
1513 which includes location, conditional, and action list.
1515 * The source command now accepts a -s option to force searching for the
1516 script in the source search path even if the script name specifies
1519 * New features in the GDB remote stub, GDBserver
1521 - GDBserver now support tracepoints (including fast tracepoints, and
1522 static tracepoints). The feature is currently supported by the
1523 i386-linux and amd64-linux builds. See the "Tracepoints support
1524 in gdbserver" section in the manual for more information.
1526 GDBserver JIT compiles the tracepoint's conditional agent
1527 expression bytecode into native code whenever possible for low
1528 overhead dynamic tracepoints conditionals. For such tracepoints,
1529 an expression that examines program state is evaluated when the
1530 tracepoint is reached, in order to determine whether to capture
1531 trace data. If the condition is simple and false, processing the
1532 tracepoint finishes very quickly and no data is gathered.
1534 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1535 for static tracepoints support.
1537 - GDBserver now supports x86_64 Windows 64-bit debugging.
1539 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1540 it understands register description.
1542 * The --batch flag now disables pagination and queries.
1544 * X86 general purpose registers
1546 GDB now supports reading/writing byte, word and double-word x86
1547 general purpose registers directly. This means you can use, say,
1548 $ah or $ax to refer, respectively, to the byte register AH and
1549 16-bit word register AX that are actually portions of the 32-bit
1550 register EAX or 64-bit register RAX.
1552 * The `commands' command now accepts a range of breakpoints to modify.
1553 A plain `commands' following a command that creates multiple
1554 breakpoints affects all the breakpoints set by that command. This
1555 applies to breakpoints set by `rbreak', and also applies when a
1556 single `break' command creates multiple breakpoints (e.g.,
1557 breakpoints on overloaded c++ functions).
1559 * The `rbreak' command now accepts a filename specification as part of
1560 its argument, limiting the functions selected by the regex to those
1561 in the specified file.
1563 * Support for remote debugging Windows and SymbianOS shared libraries
1564 from Unix hosts has been improved. Non Windows GDB builds now can
1565 understand target reported file names that follow MS-DOS based file
1566 system semantics, such as file names that include drive letters and
1567 use the backslash character as directory separator. This makes it
1568 possible to transparently use the "set sysroot" and "set
1569 solib-search-path" on Unix hosts to point as host copies of the
1570 target's shared libraries. See the new command "set
1571 target-file-system-kind" described below, and the "Commands to
1572 specify files" section in the user manual for more information.
1576 eval template, expressions...
1577 Convert the values of one or more expressions under the control
1578 of the string template to a command line, and call it.
1580 set target-file-system-kind unix|dos-based|auto
1581 show target-file-system-kind
1582 Set or show the assumed file system kind for target reported file
1585 save breakpoints <filename>
1586 Save all current breakpoint definitions to a file suitable for use
1587 in a later debugging session. To read the saved breakpoint
1588 definitions, use the `source' command.
1590 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1593 info static-tracepoint-markers
1594 Display information about static tracepoint markers in the target.
1596 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1597 Define a static tracepoint by probing a marker at the given
1598 function, line, address, or marker ID.
1602 Enable and disable observer mode.
1604 set may-write-registers on|off
1605 set may-write-memory on|off
1606 set may-insert-breakpoints on|off
1607 set may-insert-tracepoints on|off
1608 set may-insert-fast-tracepoints on|off
1609 set may-interrupt on|off
1610 Set individual permissions for GDB effects on the target. Note that
1611 some of these settings can have undesirable or surprising
1612 consequences, particularly when changed in the middle of a session.
1613 For instance, disabling the writing of memory can prevent
1614 breakpoints from being inserted, cause single-stepping to fail, or
1615 even crash your program, if you disable after breakpoints have been
1616 inserted. However, GDB should not crash.
1618 set record memory-query on|off
1619 show record memory-query
1620 Control whether to stop the inferior if memory changes caused
1621 by an instruction cannot be recorded.
1626 The disassemble command now supports "start,+length" form of two arguments.
1630 ** GDB now provides a new directory location, called the python directory,
1631 where Python scripts written for GDB can be installed. The location
1632 of that directory is <data-directory>/python, where <data-directory>
1633 is the GDB data directory. For more details, see section `Scripting
1634 GDB using Python' in the manual.
1636 ** The GDB Python API now has access to breakpoints, symbols, symbol
1637 tables, program spaces, inferiors, threads and frame's code blocks.
1638 Additionally, GDB Parameters can now be created from the API, and
1639 manipulated via set/show in the CLI.
1641 ** New functions gdb.target_charset, gdb.target_wide_charset,
1642 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1644 ** New exception gdb.GdbError.
1646 ** Pretty-printers are now also looked up in the current program space.
1648 ** Pretty-printers can now be individually enabled and disabled.
1650 ** GDB now looks for names of Python scripts to auto-load in a
1651 special section named `.debug_gdb_scripts', in addition to looking
1652 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1654 * Tracepoint actions were unified with breakpoint commands. In particular,
1655 there are no longer differences in "info break" output for breakpoints and
1656 tracepoints and the "commands" command can be used for both tracepoints and
1657 regular breakpoints.
1661 ARM Symbian arm*-*-symbianelf*
1663 * D language support.
1664 GDB now supports debugging programs written in the D programming
1667 * GDB now supports the extended ptrace interface for PowerPC which is
1668 available since Linux kernel version 2.6.34. This automatically enables
1669 any hardware breakpoints and additional hardware watchpoints available in
1670 the processor. The old ptrace interface exposes just one hardware
1671 watchpoint and no hardware breakpoints.
1673 * GDB is now able to use the Data Value Compare (DVC) register available on
1674 embedded PowerPC processors to implement in hardware simple watchpoint
1675 conditions of the form:
1677 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1679 This works in native GDB running on Linux kernels with the extended ptrace
1680 interface mentioned above.
1682 *** Changes in GDB 7.1
1686 ** Namespace Support
1688 GDB now supports importing of namespaces in C++. This enables the
1689 user to inspect variables from imported namespaces. Support for
1690 namepace aliasing has also been added. So, if a namespace is
1691 aliased in the current scope (e.g. namepace C=A; ) the user can
1692 print variables using the alias (e.g. (gdb) print C::x).
1696 All known bugs relating to the printing of virtual base class were
1697 fixed. It is now possible to call overloaded static methods using a
1702 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1703 and reinterpret_cast<> are now handled by the C++ expression parser.
1707 Xilinx MicroBlaze microblaze-*-*
1712 Xilinx MicroBlaze microblaze
1715 * Multi-program debugging.
1717 GDB now has support for multi-program (a.k.a. multi-executable or
1718 multi-exec) debugging. This allows for debugging multiple inferiors
1719 simultaneously each running a different program under the same GDB
1720 session. See "Debugging Multiple Inferiors and Programs" in the
1721 manual for more information. This implied some user visible changes
1722 in the multi-inferior support. For example, "info inferiors" now
1723 lists inferiors that are not running yet or that have exited
1724 already. See also "New commands" and "New options" below.
1726 * New tracing features
1728 GDB's tracepoint facility now includes several new features:
1730 ** Trace state variables
1732 GDB tracepoints now include support for trace state variables, which
1733 are variables managed by the target agent during a tracing
1734 experiment. They are useful for tracepoints that trigger each
1735 other, so for instance one tracepoint can count hits in a variable,
1736 and then a second tracepoint has a condition that is true when the
1737 count reaches a particular value. Trace state variables share the
1738 $-syntax of GDB convenience variables, and can appear in both
1739 tracepoint actions and condition expressions. Use the "tvariable"
1740 command to create, and "info tvariables" to view; see "Trace State
1741 Variables" in the manual for more detail.
1745 GDB now includes an option for defining fast tracepoints, which
1746 targets may implement more efficiently, such as by installing a jump
1747 into the target agent rather than a trap instruction. The resulting
1748 speedup can be by two orders of magnitude or more, although the
1749 tradeoff is that some program locations on some target architectures
1750 might not allow fast tracepoint installation, for instance if the
1751 instruction to be replaced is shorter than the jump. To request a
1752 fast tracepoint, use the "ftrace" command, with syntax identical to
1753 the regular trace command.
1755 ** Disconnected tracing
1757 It is now possible to detach GDB from the target while it is running
1758 a trace experiment, then reconnect later to see how the experiment
1759 is going. In addition, a new variable disconnected-tracing lets you
1760 tell the target agent whether to continue running a trace if the
1761 connection is lost unexpectedly.
1765 GDB now has the ability to save the trace buffer into a file, and
1766 then use that file as a target, similarly to you can do with
1767 corefiles. You can select trace frames, print data that was
1768 collected in them, and use tstatus to display the state of the
1769 tracing run at the moment that it was saved. To create a trace
1770 file, use "tsave <filename>", and to use it, do "target tfile
1773 ** Circular trace buffer
1775 You can ask the target agent to handle the trace buffer as a
1776 circular buffer, discarding the oldest trace frames to make room for
1777 newer ones, by setting circular-trace-buffer to on. This feature may
1778 not be available for all target agents.
1783 The disassemble command, when invoked with two arguments, now requires
1784 the arguments to be comma-separated.
1787 The info variables command now displays variable definitions. Files
1788 which only declare a variable are not shown.
1791 The source command is now capable of sourcing Python scripts.
1792 This feature is dependent on the debugger being build with Python
1795 Related to this enhancement is also the introduction of a new command
1796 "set script-extension" (see below).
1798 * New commands (for set/show, see "New options" below)
1800 record save [<FILENAME>]
1801 Save a file (in core file format) containing the process record
1802 execution log for replay debugging at a later time.
1804 record restore <FILENAME>
1805 Restore the process record execution log that was saved at an
1806 earlier time, for replay debugging.
1808 add-inferior [-copies <N>] [-exec <FILENAME>]
1811 clone-inferior [-copies <N>] [ID]
1812 Make a new inferior ready to execute the same program another
1813 inferior has loaded.
1818 maint info program-spaces
1819 List the program spaces loaded into GDB.
1821 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1822 show remote interrupt-sequence
1823 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1824 as the sequence to the remote target in order to interrupt the execution.
1825 Ctrl-C is a default. Some system prefers BREAK which is high level of
1826 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1827 Magic SysRq g. It is BREAK signal and character 'g'.
1829 set remote interrupt-on-connect [on | off]
1830 show remote interrupt-on-connect
1831 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1832 remote target when gdb connects to it. This is needed when you debug
1835 set remotebreak [on | off]
1837 Deprecated. Use "set/show remote interrupt-sequence" instead.
1839 tvariable $NAME [ = EXP ]
1840 Create or modify a trace state variable.
1843 List trace state variables and their values.
1845 delete tvariable $NAME ...
1846 Delete one or more trace state variables.
1849 Evaluate the given expressions without collecting anything into the
1850 trace buffer. (Valid in tracepoint actions only.)
1852 ftrace FN / FILE:LINE / *ADDR
1853 Define a fast tracepoint at the given function, line, or address.
1855 * New expression syntax
1857 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1858 GDB now parses 0b101010 identically with 42.
1862 set follow-exec-mode new|same
1863 show follow-exec-mode
1864 Control whether GDB reuses the same inferior across an exec call or
1865 creates a new one. This is useful to be able to restart the old
1866 executable after the inferior having done an exec call.
1868 set default-collect EXPR, ...
1869 show default-collect
1870 Define a list of expressions to be collected at each tracepoint.
1871 This is a useful way to ensure essential items are not overlooked,
1872 such as registers or a critical global variable.
1874 set disconnected-tracing
1875 show disconnected-tracing
1876 If set to 1, the target is instructed to continue tracing if it
1877 loses its connection to GDB. If 0, the target is to stop tracing
1880 set circular-trace-buffer
1881 show circular-trace-buffer
1882 If set to on, the target is instructed to use a circular trace buffer
1883 and discard the oldest trace frames instead of stopping the trace due
1884 to a full trace buffer. If set to off, the trace stops when the buffer
1885 fills up. Some targets may not support this.
1887 set script-extension off|soft|strict
1888 show script-extension
1889 If set to "off", the debugger does not perform any script language
1890 recognition, and all sourced files are assumed to be GDB scripts.
1891 If set to "soft" (the default), files are sourced according to
1892 filename extension, falling back to GDB scripts if the first
1894 If set to "strict", files are sourced according to filename extension.
1896 set ada trust-PAD-over-XVS on|off
1897 show ada trust-PAD-over-XVS
1898 If off, activate a workaround against a bug in the debugging information
1899 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1900 the GCC sources for more information about the GNAT encoding and
1901 PAD types in particular). It is always safe to set this option to
1902 off, but this introduces a slight performance penalty. The default
1905 * Python API Improvements
1907 ** GDB provides the new class gdb.LazyString. This is useful in
1908 some pretty-printing cases. The new method gdb.Value.lazy_string
1909 provides a simple way to create objects of this type.
1911 ** The fields returned by gdb.Type.fields now have an
1912 `is_base_class' attribute.
1914 ** The new method gdb.Type.range returns the range of an array type.
1916 ** The new method gdb.parse_and_eval can be used to parse and
1917 evaluate an expression.
1919 * New remote packets
1922 Define a trace state variable.
1925 Get the current value of a trace state variable.
1928 Set desired tracing behavior upon disconnection.
1931 Set the trace buffer to be linear or circular.
1934 Get data about the tracepoints currently in use.
1938 Process record now works correctly with hardware watchpoints.
1940 Multiple bug fixes have been made to the mips-irix port, making it
1941 much more reliable. In particular:
1942 - Debugging threaded applications is now possible again. Previously,
1943 GDB would hang while starting the program, or while waiting for
1944 the program to stop at a breakpoint.
1945 - Attaching to a running process no longer hangs.
1946 - An error occurring while loading a core file has been fixed.
1947 - Changing the value of the PC register now works again. This fixes
1948 problems observed when using the "jump" command, or when calling
1949 a function from GDB, or even when assigning a new value to $pc.
1950 - With the "finish" and "return" commands, the return value for functions
1951 returning a small array is now correctly printed.
1952 - It is now possible to break on shared library code which gets executed
1953 during a shared library init phase (code executed while executing
1954 their .init section). Previously, the breakpoint would have no effect.
1955 - GDB is now able to backtrace through the signal handler for
1956 non-threaded programs.
1958 PIE (Position Independent Executable) programs debugging is now supported.
1959 This includes debugging execution of PIC (Position Independent Code) shared
1960 libraries although for that, it should be possible to run such libraries as an
1963 *** Changes in GDB 7.0
1965 * GDB now has an interface for JIT compilation. Applications that
1966 dynamically generate code can create symbol files in memory and register
1967 them with GDB. For users, the feature should work transparently, and
1968 for JIT developers, the interface is documented in the GDB manual in the
1969 "JIT Compilation Interface" chapter.
1971 * Tracepoints may now be conditional. The syntax is as for
1972 breakpoints; either an "if" clause appended to the "trace" command,
1973 or the "condition" command is available. GDB sends the condition to
1974 the target for evaluation using the same bytecode format as is used
1975 for tracepoint actions.
1977 * The disassemble command now supports: an optional /r modifier, print the
1978 raw instructions in hex as well as in symbolic form, and an optional /m
1979 modifier to print mixed source+assembly.
1981 * Process record and replay
1983 In a architecture environment that supports ``process record and
1984 replay'', ``process record and replay'' target can record a log of
1985 the process execution, and replay it with both forward and reverse
1988 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1989 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1990 set execution-direction {forward|reverse}, for targets that support
1993 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1994 feature is available with a native GDB running on kernel version
1997 * GDB now has support for multi-byte and wide character sets on the
1998 target. Strings whose character type is wchar_t, char16_t, or
1999 char32_t are now correctly printed. GDB supports wide- and unicode-
2000 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2001 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2002 `printf'. This feature requires iconv to work properly; if your
2003 system does not have a working iconv, GDB can use GNU libiconv. See
2004 the installation instructions for more information.
2006 * GDB now supports automatic retrieval of shared library files from
2007 remote targets. To use this feature, specify a system root that begins
2008 with the `remote:' prefix, either via the `set sysroot' command or via
2009 the `--with-sysroot' configure-time option.
2011 * "info sharedlibrary" now takes an optional regex of libraries to show,
2012 and it now reports if a shared library has no debugging information.
2014 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2015 now complete on file names.
2017 * When completing in expressions, gdb will attempt to limit
2018 completions to allowable structure or union fields, where appropriate.
2019 For instance, consider:
2021 # struct example { int f1; double f2; };
2022 # struct example variable;
2025 If the user types TAB at the end of this command line, the available
2026 completions will be "f1" and "f2".
2028 * Inlined functions are now supported. They show up in backtraces, and
2029 the "step", "next", and "finish" commands handle them automatically.
2031 * GDB now supports the token-splicing (##) and stringification (#)
2032 operators when expanding macros. It also supports variable-arity
2035 * GDB now supports inspecting extra signal information, exported by
2036 the new $_siginfo convenience variable. The feature is currently
2037 implemented on linux ARM, i386 and amd64.
2039 * GDB can now display the VFP floating point registers and NEON vector
2040 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2041 can provide these registers (requires Linux 2.6.30 or later). Remote
2042 and simulator targets may also provide them.
2044 * New remote packets
2047 Search memory for a sequence of bytes.
2050 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2051 operation over reliable transport links. Use of this packet is
2052 controlled by the `set remote noack-packet' command.
2055 Kill the process with the specified process ID. Use this in preference
2056 to `k' when multiprocess protocol extensions are supported.
2059 Obtains additional operating system information
2063 Read or write additional signal information.
2065 * Removed remote protocol undocumented extension
2067 An undocumented extension to the remote protocol's `S' stop reply
2068 packet that permited the stub to pass a process id was removed.
2069 Remote servers should use the `T' stop reply packet instead.
2071 * GDB now supports multiple function calling conventions according to the
2072 DWARF-2 DW_AT_calling_convention function attribute.
2074 * The SH target utilizes the aforementioned change to distinguish between gcc
2075 and Renesas calling convention. It also adds the new CLI commands
2076 `set/show sh calling-convention'.
2078 * GDB can now read compressed debug sections, as produced by GNU gold
2079 with the --compress-debug-sections=zlib flag.
2081 * 64-bit core files are now supported on AIX.
2083 * Thread switching is now supported on Tru64.
2085 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2086 which will be allocated using malloc later in program execution.
2088 * The qXfer:libraries:read remote procotol packet now allows passing a
2089 list of section offsets.
2091 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2092 conditions handling signals delivered during attach or thread creation
2093 have also been fixed.
2095 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2096 From the user's standpoint, all unqualified instances of True and False
2097 are treated as the standard definitions, regardless of context.
2099 * GDB now parses C++ symbol and type names more flexibly. For
2102 template<typename T> class C { };
2105 GDB will now correctly handle all of:
2107 ptype C<char const *>
2108 ptype C<char const*>
2109 ptype C<const char *>
2110 ptype C<const char*>
2112 * New features in the GDB remote stub, gdbserver
2114 - The "--wrapper" command-line argument tells gdbserver to use a
2115 wrapper program to launch programs for debugging.
2117 - On PowerPC and S/390 targets, it is now possible to use a single
2118 gdbserver executable to debug both 32-bit and 64-bit programs.
2119 (This requires gdbserver itself to be built as a 64-bit executable.)
2121 - gdbserver uses the new noack protocol mode for TCP connections to
2122 reduce communications latency, if also supported and enabled in GDB.
2124 - Support for the sparc64-linux-gnu target is now included in
2127 - The amd64-linux build of gdbserver now supports debugging both
2128 32-bit and 64-bit programs.
2130 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2131 now support hardware watchpoints, and will use them automatically
2136 GDB now has support for scripting using Python. Whether this is
2137 available is determined at configure time.
2139 New GDB commands can now be written in Python.
2141 * Ada tasking support
2143 Ada tasks can now be inspected in GDB. The following commands have
2147 Print the list of Ada tasks.
2149 Print detailed information about task number N.
2151 Print the task number of the current task.
2153 Switch the context of debugging to task number N.
2155 * Support for user-defined prefixed commands. The "define" command can
2156 add new commands to existing prefixes, e.g. "target".
2158 * Multi-inferior, multi-process debugging.
2160 GDB now has generalized support for multi-inferior debugging. See
2161 "Debugging Multiple Inferiors" in the manual for more information.
2162 Although availability still depends on target support, the command
2163 set is more uniform now. The GNU/Linux specific multi-forks support
2164 has been migrated to this new framework. This implied some user
2165 visible changes; see "New commands" and also "Removed commands"
2168 * Target descriptions can now describe the target OS ABI. See the
2169 "Target Description Format" section in the user manual for more
2172 * Target descriptions can now describe "compatible" architectures
2173 to indicate that the target can execute applications for a different
2174 architecture in addition to those for the main target architecture.
2175 See the "Target Description Format" section in the user manual for
2178 * Multi-architecture debugging.
2180 GDB now includes general supports for debugging applications on
2181 hybrid systems that use more than one single processor architecture
2182 at the same time. Each such hybrid architecture still requires
2183 specific support to be added. The only hybrid architecture supported
2184 in this version of GDB is the Cell Broadband Engine.
2186 * GDB now supports integrated debugging of Cell/B.E. applications that
2187 use both the PPU and SPU architectures. To enable support for hybrid
2188 Cell/B.E. debugging, you need to configure GDB to support both the
2189 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2190 --enable-targets configure option.
2192 * Non-stop mode debugging.
2194 For some targets, GDB now supports an optional mode of operation in
2195 which you can examine stopped threads while other threads continue
2196 to execute freely. This is referred to as non-stop mode, with the
2197 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2198 section in the user manual for more information.
2200 To be able to support remote non-stop debugging, a remote stub needs
2201 to implement the non-stop mode remote protocol extensions, as
2202 described in the "Remote Non-Stop" section of the user manual. The
2203 GDB remote stub, gdbserver, has been adjusted to support these
2204 extensions on linux targets.
2206 * New commands (for set/show, see "New options" below)
2208 catch syscall [NAME(S) | NUMBER(S)]
2209 Catch system calls. Arguments, which should be names of system
2210 calls or their numbers, mean catch only those syscalls. Without
2211 arguments, every syscall will be caught. When the inferior issues
2212 any of the specified syscalls, GDB will stop and announce the system
2213 call, both when it is called and when its call returns. This
2214 feature is currently available with a native GDB running on the
2215 Linux Kernel, under the following architectures: x86, x86_64,
2216 PowerPC and PowerPC64.
2218 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2220 Search memory for a sequence of bytes.
2222 maint set python print-stack
2223 maint show python print-stack
2224 Show a stack trace when an error is encountered in a Python script.
2227 Invoke CODE by passing it to the Python interpreter.
2232 These allow macros to be defined, undefined, and listed
2236 Show operating system information about processes.
2239 List the inferiors currently under GDB's control.
2242 Switch focus to inferior number NUM.
2245 Detach from inferior number NUM.
2248 Kill inferior number NUM.
2252 set spu stop-on-load
2253 show spu stop-on-load
2254 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2256 set spu auto-flush-cache
2257 show spu auto-flush-cache
2258 Control whether to automatically flush the software-managed cache
2259 during Cell/B.E. debugging.
2261 set sh calling-convention
2262 show sh calling-convention
2263 Control the calling convention used when calling SH target functions.
2266 show debug timestamp
2267 Control display of timestamps with GDB debugging output.
2269 set disassemble-next-line
2270 show disassemble-next-line
2271 Control display of disassembled source lines or instructions when
2274 set remote noack-packet
2275 show remote noack-packet
2276 Set/show the use of remote protocol QStartNoAckMode packet. See above
2277 under "New remote packets."
2279 set remote query-attached-packet
2280 show remote query-attached-packet
2281 Control use of remote protocol `qAttached' (query-attached) packet.
2283 set remote read-siginfo-object
2284 show remote read-siginfo-object
2285 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2288 set remote write-siginfo-object
2289 show remote write-siginfo-object
2290 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2293 set remote reverse-continue
2294 show remote reverse-continue
2295 Control use of remote protocol 'bc' (reverse-continue) packet.
2297 set remote reverse-step
2298 show remote reverse-step
2299 Control use of remote protocol 'bs' (reverse-step) packet.
2301 set displaced-stepping
2302 show displaced-stepping
2303 Control displaced stepping mode. Displaced stepping is a way to
2304 single-step over breakpoints without removing them from the debuggee.
2305 Also known as "out-of-line single-stepping".
2308 show debug displaced
2309 Control display of debugging info for displaced stepping.
2311 maint set internal-error
2312 maint show internal-error
2313 Control what GDB does when an internal error is detected.
2315 maint set internal-warning
2316 maint show internal-warning
2317 Control what GDB does when an internal warning is detected.
2322 Use a wrapper program to launch programs for debugging.
2324 set multiple-symbols (all|ask|cancel)
2325 show multiple-symbols
2326 The value of this variable can be changed to adjust the debugger behavior
2327 when an expression or a breakpoint location contains an ambiguous symbol
2328 name (an overloaded function name, for instance).
2330 set breakpoint always-inserted
2331 show breakpoint always-inserted
2332 Keep breakpoints always inserted in the target, as opposed to inserting
2333 them when resuming the target, and removing them when the target stops.
2334 This option can improve debugger performance on slow remote targets.
2336 set arm fallback-mode (arm|thumb|auto)
2337 show arm fallback-mode
2338 set arm force-mode (arm|thumb|auto)
2340 These commands control how ARM GDB determines whether instructions
2341 are ARM or Thumb. The default for both settings is auto, which uses
2342 the current CPSR value for instructions without symbols; previous
2343 versions of GDB behaved as if "set arm fallback-mode arm".
2345 set disable-randomization
2346 show disable-randomization
2347 Standalone programs run with the virtual address space randomization enabled
2348 by default on some platforms. This option keeps the addresses stable across
2349 multiple debugging sessions.
2353 Control whether other threads are stopped or not when some thread hits
2358 Requests that asynchronous execution is enabled in the target, if available.
2359 In this case, it's possible to resume target in the background, and interact
2360 with GDB while the target is running. "show target-async" displays the
2361 current state of asynchronous execution of the target.
2363 set target-wide-charset
2364 show target-wide-charset
2365 The target-wide-charset is the name of the character set that GDB
2366 uses when printing characters whose type is wchar_t.
2368 set tcp auto-retry (on|off)
2370 set tcp connect-timeout
2371 show tcp connect-timeout
2372 These commands allow GDB to retry failed TCP connections to a remote stub
2373 with a specified timeout period; this is useful if the stub is launched
2374 in parallel with GDB but may not be ready to accept connections immediately.
2376 set libthread-db-search-path
2377 show libthread-db-search-path
2378 Control list of directories which GDB will search for appropriate
2381 set schedule-multiple (on|off)
2382 show schedule-multiple
2383 Allow GDB to resume all threads of all processes or only threads of
2384 the current process.
2388 Use more aggressive caching for accesses to the stack. This improves
2389 performance of remote debugging (particularly backtraces) without
2390 affecting correctness.
2392 set interactive-mode (on|off|auto)
2393 show interactive-mode
2394 Control whether GDB runs in interactive mode (on) or not (off).
2395 When in interactive mode, GDB waits for the user to answer all
2396 queries. Otherwise, GDB does not wait and assumes the default
2397 answer. When set to auto (the default), GDB determines which
2398 mode to use based on the stdin settings.
2403 For program forks, this is replaced by the new more generic `info
2404 inferiors' command. To list checkpoints, you can still use the
2405 `info checkpoints' command, which was an alias for the `info forks'
2409 Replaced by the new `inferior' command. To switch between
2410 checkpoints, you can still use the `restart' command, which was an
2411 alias for the `fork' command.
2414 This is removed, since some targets don't have a notion of
2415 processes. To switch between processes, you can still use the
2416 `inferior' command using GDB's own inferior number.
2419 For program forks, this is replaced by the new more generic `kill
2420 inferior' command. To delete a checkpoint, you can still use the
2421 `delete checkpoint' command, which was an alias for the `delete
2425 For program forks, this is replaced by the new more generic `detach
2426 inferior' command. To detach a checkpoint, you can still use the
2427 `detach checkpoint' command, which was an alias for the `detach
2430 * New native configurations
2432 x86/x86_64 Darwin i[34567]86-*-darwin*
2434 x86_64 MinGW x86_64-*-mingw*
2438 Lattice Mico32 lm32-*
2439 x86 DICOS i[34567]86-*-dicos*
2440 x86_64 DICOS x86_64-*-dicos*
2443 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2444 (mingw32ce) debugging.
2450 These commands were actually not implemented on any target.
2452 *** Changes in GDB 6.8
2454 * New native configurations
2456 NetBSD/hppa hppa*-*netbsd*
2457 Xtensa GNU/Linux xtensa*-*-linux*
2461 NetBSD/hppa hppa*-*-netbsd*
2462 Xtensa GNU/Lunux xtensa*-*-linux*
2464 * Change in command line behavior -- corefiles vs. process ids.
2466 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2467 attaching to process NUMBER fails, GDB no longer attempts to open a
2468 core file named NUMBER. Attaching to a program using the -c option
2469 is no longer supported. Instead, use the '-p' or '--pid' options.
2471 * GDB can now be built as a native debugger for debugging Windows x86
2472 (mingw32) Portable Executable (PE) programs.
2474 * Pending breakpoints no longer change their number when their address
2477 * GDB now supports breakpoints with multiple locations,
2478 including breakpoints on C++ constructors, inside C++ templates,
2479 and in inlined functions.
2481 * GDB's ability to debug optimized code has been improved. GDB more
2482 accurately identifies function bodies and lexical blocks that occupy
2483 more than one contiguous range of addresses.
2485 * Target descriptions can now describe registers for PowerPC.
2487 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2488 registers on PowerPC targets.
2490 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2491 targets even when the libthread_db library is not available.
2493 * The GDB remote stub, gdbserver, now supports the new file transfer
2494 commands (remote put, remote get, and remote delete).
2496 * The GDB remote stub, gdbserver, now supports run and attach in
2497 extended-remote mode.
2499 * hppa*64*-*-hpux11* target broken
2500 The debugger is unable to start a program and fails with the following
2501 error: "Error trying to get information about dynamic linker".
2502 The gdb-6.7 release is also affected.
2504 * GDB now supports the --enable-targets= configure option to allow
2505 building a single GDB executable that supports multiple remote
2506 target architectures.
2508 * GDB now supports debugging C and C++ programs which use the
2509 Decimal Floating Point extension. In addition, the PowerPC target
2510 now has a set of pseudo-registers to inspect decimal float values
2511 stored in two consecutive float registers.
2513 * The -break-insert MI command can optionally create pending
2516 * Improved support for debugging Ada
2517 Many improvements to the Ada language support have been made. These
2519 - Better support for Ada2005 interface types
2520 - Improved handling of arrays and slices in general
2521 - Better support for Taft-amendment types
2522 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2524 - Improved command completion in Ada
2527 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2532 set print frame-arguments (all|scalars|none)
2533 show print frame-arguments
2534 The value of this variable can be changed to control which argument
2535 values should be printed by the debugger when displaying a frame.
2540 Transfer files to and from a remote target, and delete remote files.
2547 Transfer files to and from a remote target, and delete remote files.
2549 * New remote packets
2556 Open, close, read, write, and delete files on the remote system.
2559 Attach to an existing process on the remote system, in extended-remote
2563 Run a new process on the remote system, in extended-remote mode.
2565 *** Changes in GDB 6.7
2567 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2568 bfd, libiberty and opcodes, as revealed by static analysis donated by
2569 Coverity, Inc. (http://scan.coverity.com).
2571 * When looking up multiply-defined global symbols, GDB will now prefer the
2572 symbol definition in the current shared library if it was built using the
2573 -Bsymbolic linker option.
2575 * When the Text User Interface (TUI) is not configured, GDB will now
2576 recognize the -tui command-line option and print a message that the TUI
2579 * The GDB remote stub, gdbserver, now has lower overhead for high
2580 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2582 * GDB for MIPS targets now autodetects whether a remote target provides
2583 32-bit or 64-bit register values.
2585 * Support for C++ member pointers has been improved.
2587 * GDB now understands XML target descriptions, which specify the
2588 target's overall architecture. GDB can read a description from
2589 a local file or over the remote serial protocol.
2591 * Vectors of single-byte data use a new integer type which is not
2592 automatically displayed as character or string data.
2594 * The /s format now works with the print command. It displays
2595 arrays of single-byte integers and pointers to single-byte integers
2598 * Target descriptions can now describe target-specific registers,
2599 for architectures which have implemented the support (currently
2600 only ARM, M68K, and MIPS).
2602 * GDB and the GDB remote stub, gdbserver, now support the XScale
2605 * The GDB remote stub, gdbserver, has been updated to support
2606 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2607 has been rewritten to use the standard GDB remote protocol.
2609 * GDB can now step into C++ functions which are called through thunks.
2611 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2613 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2614 layout. It also supports a TextSeg= and DataSeg= response when only
2615 segment base addresses (rather than offsets) are available.
2617 * The /i format now outputs any trailing branch delay slot instructions
2618 immediately following the last instruction within the count specified.
2620 * The GDB remote protocol "T" stop reply packet now supports a
2621 "library" response. Combined with the new "qXfer:libraries:read"
2622 packet, this response allows GDB to debug shared libraries on targets
2623 where the operating system manages the list of loaded libraries (e.g.
2624 Windows and SymbianOS).
2626 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2627 (DLLs) on Windows and Windows CE targets.
2629 * GDB now supports a faster verification that a .debug file matches its binary
2630 according to its build-id signature, if the signature is present.
2636 Enable or disable hardware flow control (RTS/CTS) on the serial port
2637 when debugging using remote targets.
2639 set mem inaccessible-by-default
2640 show mem inaccessible-by-default
2641 If the target supplies a memory map, for instance via the remote
2642 protocol's "qXfer:memory-map:read" packet, setting this variable
2643 prevents GDB from accessing memory outside the memory map. This
2644 is useful for targets with memory mapped registers or which react
2645 badly to accesses of unmapped address space.
2647 set breakpoint auto-hw
2648 show breakpoint auto-hw
2649 If the target supplies a memory map, for instance via the remote
2650 protocol's "qXfer:memory-map:read" packet, setting this variable
2651 lets GDB use hardware breakpoints automatically for memory regions
2652 where it can not use software breakpoints. This covers both the
2653 "break" command and internal breakpoints used for other commands
2654 including "next" and "finish".
2657 catch exception unhandled
2658 Stop the program execution when Ada exceptions are raised.
2661 Stop the program execution when an Ada assertion failed.
2665 Set an alternate system root for target files. This is a more
2666 general version of "set solib-absolute-prefix", which is now
2667 an alias to "set sysroot".
2670 Provide extended SPU facility status information. This set of
2671 commands is available only when debugging the Cell/B.E. SPU
2674 * New native configurations
2676 OpenBSD/sh sh*-*openbsd*
2679 unset tdesc filename
2681 Use the specified local file as an XML target description, and do
2682 not query the target for its built-in description.
2686 OpenBSD/sh sh*-*-openbsd*
2687 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2688 Toshiba Media Processor mep-elf
2690 * New remote packets
2693 Ignore the specified signals; pass them directly to the debugged program
2694 without stopping other threads or reporting them to GDB.
2696 qXfer:features:read:
2697 Read an XML target description from the target, which describes its
2702 Read or write contents of an spufs file on the target system. These
2703 packets are available only on the Cell/B.E. SPU architecture.
2705 qXfer:libraries:read:
2706 Report the loaded shared libraries. Combined with new "T" packet
2707 response, this packet allows GDB to debug shared libraries on
2708 targets where the operating system manages the list of loaded
2709 libraries (e.g. Windows and SymbianOS).
2713 Support for these obsolete configurations has been removed.
2721 i[34567]86-*-lynxos*
2722 i[34567]86-*-netware*
2723 i[34567]86-*-sco3.2v5*
2724 i[34567]86-*-sco3.2v4*
2726 i[34567]86-*-sysv4.2*
2729 i[34567]86-*-unixware2*
2730 i[34567]86-*-unixware*
2739 * Other removed features
2746 Various m68k-only ROM monitors.
2753 Various Renesas ROM monitors and debugging interfaces for SH and
2758 Support for a Macraigor serial interface to on-chip debugging.
2759 GDB does not directly support the newer parallel or USB
2764 A debug information format. The predecessor to DWARF 2 and
2765 DWARF 3, which are still supported.
2767 Support for the HP aCC compiler on HP-UX/PA-RISC
2769 SOM-encapsulated symbolic debugging information, automatic
2770 invocation of pxdb, and the aCC custom C++ ABI. This does not
2771 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2772 with aCC can still be debugged on an assembly level.
2774 MIPS ".pdr" sections
2776 A MIPS-specific format used to describe stack frame layout
2777 in debugging information.
2781 GDB could work with an older version of Guile to debug
2782 the interpreter and Scheme programs running in it.
2784 set mips stack-arg-size
2785 set mips saved-gpreg-size
2787 Use "set mips abi" to control parameter passing for MIPS.
2789 *** Changes in GDB 6.6
2794 Cell Broadband Engine SPU spu-elf
2796 * GDB can now be configured as a cross-debugger targeting native Windows
2797 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2798 running on a Windows system over TCP/IP to debug Windows programs.
2800 * The GDB remote stub, gdbserver, has been updated to support Windows and
2801 Cygwin debugging. Both single-threaded and multi-threaded programs are
2804 * The "set trust-readonly-sections" command works again. This command was
2805 broken in GDB 6.3, 6.4, and 6.5.
2807 * The "load" command now supports writing to flash memory, if the remote
2808 stub provides the required support.
2810 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2811 longer requires symbolic debug information (e.g. DWARF-2).
2816 unset substitute-path
2817 show substitute-path
2818 Manage a list of substitution rules that GDB uses to rewrite the name
2819 of the directories where the sources are located. This can be useful
2820 for instance when the sources were moved to a different location
2821 between compilation and debugging.
2825 Print each CLI command as it is executed. Each command is prefixed with
2826 a number of `+' symbols representing the nesting depth.
2827 The source command now has a `-v' option to enable the same feature.
2831 The ARM Demon monitor support (RDP protocol, "target rdp").
2833 Kernel Object Display, an embedded debugging feature which only worked with
2834 an obsolete version of Cisco IOS.
2836 The 'set download-write-size' and 'show download-write-size' commands.
2838 * New remote packets
2841 Tell a stub about GDB client features, and request remote target features.
2842 The first feature implemented is PacketSize, which allows the target to
2843 specify the size of packets it can handle - to minimize the number of
2844 packets required and improve performance when connected to a remote
2848 Fetch an OS auxilliary vector from the remote stub. This packet is a
2849 more efficient replacement for qPart:auxv:read.
2851 qXfer:memory-map:read:
2852 Fetch a memory map from the remote stub, including information about
2853 RAM, ROM, and flash memory devices.
2858 Erase and program a flash memory device.
2860 * Removed remote packets
2863 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2864 used it, and only gdbserver implemented it.
2866 *** Changes in GDB 6.5
2870 Renesas M32C/M16C m32c-elf
2872 Morpho Technologies ms1 ms1-elf
2876 init-if-undefined Initialize a convenience variable, but
2877 only if it doesn't already have a value.
2879 The following commands are presently only implemented for native GNU/Linux:
2881 checkpoint Save a snapshot of the program state.
2883 restart <n> Return the program state to a
2884 previously saved state.
2886 info checkpoints List currently saved checkpoints.
2888 delete-checkpoint <n> Delete a previously saved checkpoint.
2890 set|show detach-on-fork Tell gdb whether to detach from a newly
2891 forked process, or to keep debugging it.
2893 info forks List forks of the user program that
2894 are available to be debugged.
2896 fork <n> Switch to debugging one of several
2897 forks of the user program that are
2898 available to be debugged.
2900 delete-fork <n> Delete a fork from the list of forks
2901 that are available to be debugged (and
2902 kill the forked process).
2904 detach-fork <n> Delete a fork from the list of forks
2905 that are available to be debugged (and
2906 allow the process to continue).
2910 Morpho Technologies ms2 ms1-elf
2912 * Improved Windows host support
2914 GDB now builds as a cross debugger hosted on i686-mingw32, including
2915 native console support, and remote communications using either
2916 network sockets or serial ports.
2918 * Improved Modula-2 language support
2920 GDB can now print most types in the Modula-2 syntax. This includes:
2921 basic types, set types, record types, enumerated types, range types,
2922 pointer types and ARRAY types. Procedure var parameters are correctly
2923 printed and hexadecimal addresses and character constants are also
2924 written in the Modula-2 syntax. Best results can be obtained by using
2925 GNU Modula-2 together with the -gdwarf-2 command line option.
2929 The ARM rdi-share module.
2931 The Netware NLM debug server.
2933 *** Changes in GDB 6.4
2935 * New native configurations
2937 OpenBSD/arm arm*-*-openbsd*
2938 OpenBSD/mips64 mips64-*-openbsd*
2942 Morpho Technologies ms1 ms1-elf
2944 * New command line options
2946 --batch-silent As for --batch, but totally silent.
2947 --return-child-result The debugger will exist with the same value
2948 the child (debugged) program exited with.
2949 --eval-command COMMAND, -ex COMMAND
2950 Execute a single GDB CLI command. This may be
2951 specified multiple times and in conjunction
2952 with the --command (-x) option.
2954 * Deprecated commands removed
2956 The following commands, that were deprecated in 2000, have been
2960 set|show arm disassembly-flavor set|show arm disassembler
2961 othernames set arm disassembler
2962 set|show remotedebug set|show debug remote
2963 set|show archdebug set|show debug arch
2964 set|show eventdebug set|show debug event
2967 * New BSD user-level threads support
2969 It is now possible to debug programs using the user-level threads
2970 library on OpenBSD and FreeBSD. Currently supported (target)
2973 FreeBSD/amd64 x86_64-*-freebsd*
2974 FreeBSD/i386 i386-*-freebsd*
2975 OpenBSD/i386 i386-*-openbsd*
2977 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2978 are not yet supported.
2980 * New support for Matsushita MN10300 w/sim added
2981 (Work in progress). mn10300-elf.
2983 * REMOVED configurations and files
2985 VxWorks and the XDR protocol *-*-vxworks
2986 Motorola MCORE mcore-*-*
2987 National Semiconductor NS32000 ns32k-*-*
2989 * New "set print array-indexes" command
2991 After turning this setting "on", GDB prints the index of each element
2992 when displaying arrays. The default is "off" to preserve the previous
2995 * VAX floating point support
2997 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2999 * User-defined command support
3001 In addition to using $arg0..$arg9 for argument passing, it is now possible
3002 to use $argc to determine now many arguments have been passed. See the
3003 section on user-defined commands in the user manual for more information.
3005 *** Changes in GDB 6.3:
3007 * New command line option
3009 GDB now accepts -l followed by a number to set the timeout for remote
3012 * GDB works with GCC -feliminate-dwarf2-dups
3014 GDB now supports a more compact representation of DWARF-2 debug
3015 information using DW_FORM_ref_addr references. These are produced
3016 by GCC with the option -feliminate-dwarf2-dups and also by some
3017 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3018 to use -feliminate-dwarf2-dups.
3020 * Internationalization
3022 When supported by the host system, GDB will be built with
3023 internationalization (libintl). The task of marking up the sources is
3024 continued, we're looking forward to our first translation.
3028 Initial support for debugging programs compiled with the GNAT
3029 implementation of the Ada programming language has been integrated
3030 into GDB. In this release, support is limited to expression evaluation.
3032 * New native configurations
3034 GNU/Linux/m32r m32r-*-linux-gnu
3038 GDB's remote protocol now includes support for the 'p' packet. This
3039 packet is used to fetch individual registers from a remote inferior.
3041 * END-OF-LIFE registers[] compatibility module
3043 GDB's internal register infrastructure has been completely rewritten.
3044 The new infrastructure making possible the implementation of key new
3045 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3048 GDB 6.3 will be the last release to include the the registers[]
3049 compatibility module that allowed out-of-date configurations to
3050 continue to work. This change directly impacts the following
3060 powerpc bdm protocol
3062 Unless there is activity to revive these configurations, they will be
3063 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3065 * OBSOLETE configurations and files
3067 Configurations that have been declared obsolete in this release have
3068 been commented out. Unless there is activity to revive these
3069 configurations, the next release of GDB will have their sources
3070 permanently REMOVED.
3079 *** Changes in GDB 6.2.1:
3081 * MIPS `break main; run' gave an heuristic-fence-post warning
3083 When attempting to run even a simple program, a warning about
3084 heuristic-fence-post being hit would be reported. This problem has
3087 * MIPS IRIX 'long double' crashed GDB
3089 When examining a long double variable, GDB would get a segmentation
3090 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3091 IRIX long double values).
3095 A bug in the VAX stack code was causing problems with the "next"
3096 command. This problem has been fixed.
3098 *** Changes in GDB 6.2:
3100 * Fix for ``many threads''
3102 On GNU/Linux systems that use the NPTL threads library, a program
3103 rapidly creating and deleting threads would confuse GDB leading to the
3106 ptrace: No such process.
3107 thread_db_get_info: cannot get thread info: generic error
3109 This problem has been fixed.
3111 * "-async" and "-noasync" options removed.
3113 Support for the broken "-noasync" option has been removed (it caused
3116 * New ``start'' command.
3118 This command runs the program until the begining of the main procedure.
3120 * New BSD Kernel Data Access Library (libkvm) interface
3122 Using ``target kvm'' it is now possible to debug kernel core dumps and
3123 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3124 platforms. Currently supported (native-only) configurations are:
3126 FreeBSD/amd64 x86_64-*-freebsd*
3127 FreeBSD/i386 i?86-*-freebsd*
3128 NetBSD/i386 i?86-*-netbsd*
3129 NetBSD/m68k m68*-*-netbsd*
3130 NetBSD/sparc sparc-*-netbsd*
3131 OpenBSD/amd64 x86_64-*-openbsd*
3132 OpenBSD/i386 i?86-*-openbsd*
3133 OpenBSD/m68k m68*-openbsd*
3134 OpenBSD/sparc sparc-*-openbsd*
3136 * Signal trampoline code overhauled
3138 Many generic problems with GDB's signal handling code have been fixed.
3139 These include: backtraces through non-contiguous stacks; recognition
3140 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3141 call; backtrace through a signal trampoline; step into and out of
3142 signal handlers; and single-stepping in the signal trampoline.
3144 Please note that kernel bugs are a limiting factor here. These
3145 features have been shown to work on an s390 GNU/Linux system that
3146 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3148 * Cygwin support for DWARF 2 added.
3150 * New native configurations
3152 GNU/Linux/hppa hppa*-*-linux*
3153 OpenBSD/hppa hppa*-*-openbsd*
3154 OpenBSD/m68k m68*-*-openbsd*
3155 OpenBSD/m88k m88*-*-openbsd*
3156 OpenBSD/powerpc powerpc-*-openbsd*
3157 NetBSD/vax vax-*-netbsd*
3158 OpenBSD/vax vax-*-openbsd*
3160 * END-OF-LIFE frame compatibility module
3162 GDB's internal frame infrastructure has been completely rewritten.
3163 The new infrastructure making it possible to support key new features
3164 including DWARF 2 Call Frame Information. To aid in the task of
3165 migrating old configurations to this new infrastructure, a
3166 compatibility module, that allowed old configurations to continue to
3167 work, was also included.
3169 GDB 6.2 will be the last release to include this frame compatibility
3170 module. This change directly impacts the following configurations:
3180 Unless there is activity to revive these configurations, they will be
3181 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3183 * REMOVED configurations and files
3185 Sun 3, running SunOS 3 m68*-*-sunos3*
3186 Sun 3, running SunOS 4 m68*-*-sunos4*
3187 Sun 2, running SunOS 3 m68000-*-sunos3*
3188 Sun 2, running SunOS 4 m68000-*-sunos4*
3189 Motorola 680x0 running LynxOS m68*-*-lynxos*
3190 AT&T 3b1/Unix pc m68*-att-*
3191 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3192 decstation mips-dec-* mips-little-*
3193 riscos mips-*-riscos* mips-*-sysv*
3194 sonymips mips-sony-*
3195 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3197 *** Changes in GDB 6.1.1:
3199 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3201 The TUI (Text-mode User Interface) is now built as part of a default
3202 GDB configuration. It is enabled by either selecting the TUI with the
3203 command line option "-i=tui" or by running the separate "gdbtui"
3204 program. For more information on the TUI, see the manual "Debugging
3207 * Pending breakpoint support (also included in GDB 6.1)
3209 Support has been added to allow you to specify breakpoints in shared
3210 libraries that have not yet been loaded. If a breakpoint location
3211 cannot be found, and the "breakpoint pending" option is set to auto,
3212 GDB queries you if you wish to make the breakpoint pending on a future
3213 shared-library load. If and when GDB resolves the breakpoint symbol,
3214 the pending breakpoint is removed as one or more regular breakpoints
3217 Pending breakpoints are very useful for GCJ Java debugging.
3219 * Fixed ISO-C build problems
3221 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3222 non ISO-C code that stopped them being built using a more strict ISO-C
3223 compiler (e.g., IBM's C compiler).
3225 * Fixed build problem on IRIX 5
3227 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3228 wasn't able to compile compile on an IRIX 5 system.
3230 * Added execute permission to gdb/gdbserver/configure
3232 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3233 permission. This bug would cause configure to fail on a number of
3234 systems (Solaris, IRIX). Ref: server/519.
3236 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3238 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3239 has been updated to use constant array sizes.
3241 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3243 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3244 its generated DWARF Call Frame Info. This encoding was causing GDB to
3245 panic, that panic has been fixed. Ref: gdb/1628.
3247 * Fixed a problem when examining parameters in shared library code.
3249 When examining parameters in optimized shared library code generated
3250 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3251 not available''. GDB now correctly displays the variable's value.
3253 *** Changes in GDB 6.1:
3255 * Removed --with-mmalloc
3257 Support for the mmalloc memory manager has been removed, as it
3258 conflicted with the internal gdb byte cache.
3260 * Changes in AMD64 configurations
3262 The AMD64 target now includes the %cs and %ss registers. As a result
3263 the AMD64 remote protocol has changed; this affects the floating-point
3264 and SSE registers. If you rely on those registers for your debugging,
3265 you should upgrade gdbserver on the remote side.
3267 * Revised SPARC target
3269 The SPARC target has been completely revised, incorporating the
3270 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3271 support for LynxOS and SunOS 4 has been dropped. Calling functions
3272 from within GDB on operating systems with a non-executable stack
3273 (Solaris, OpenBSD) now works.
3277 GDB has a new C++ demangler which does a better job on the mangled
3278 names generated by current versions of g++. It also runs faster, so
3279 with this and other changes gdb should now start faster on large C++
3282 * DWARF 2 Location Expressions
3284 GDB support for location expressions has been extended to support function
3285 arguments and frame bases. Older versions of GDB could crash when they
3288 * C++ nested types and namespaces
3290 GDB's support for nested types and namespaces in C++ has been
3291 improved, especially if you use the DWARF 2 debugging format. (This
3292 is the default for recent versions of GCC on most platforms.)
3293 Specifically, if you have a class "Inner" defined within a class or
3294 namespace "Outer", then GDB realizes that the class's name is
3295 "Outer::Inner", not simply "Inner". This should greatly reduce the
3296 frequency of complaints about not finding RTTI symbols. In addition,
3297 if you are stopped at inside of a function defined within a namespace,
3298 GDB modifies its name lookup accordingly.
3300 * New native configurations
3302 NetBSD/amd64 x86_64-*-netbsd*
3303 OpenBSD/amd64 x86_64-*-openbsd*
3304 OpenBSD/alpha alpha*-*-openbsd*
3305 OpenBSD/sparc sparc-*-openbsd*
3306 OpenBSD/sparc64 sparc64-*-openbsd*
3308 * New debugging protocols
3310 M32R with SDI protocol m32r-*-elf*
3312 * "set prompt-escape-char" command deleted.
3314 The command "set prompt-escape-char" has been deleted. This command,
3315 and its very obscure effet on GDB's prompt, was never documented,
3316 tested, nor mentioned in the NEWS file.
3318 * OBSOLETE configurations and files
3320 Configurations that have been declared obsolete in this release have
3321 been commented out. Unless there is activity to revive these
3322 configurations, the next release of GDB will have their sources
3323 permanently REMOVED.
3325 Sun 3, running SunOS 3 m68*-*-sunos3*
3326 Sun 3, running SunOS 4 m68*-*-sunos4*
3327 Sun 2, running SunOS 3 m68000-*-sunos3*
3328 Sun 2, running SunOS 4 m68000-*-sunos4*
3329 Motorola 680x0 running LynxOS m68*-*-lynxos*
3330 AT&T 3b1/Unix pc m68*-att-*
3331 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3332 decstation mips-dec-* mips-little-*
3333 riscos mips-*-riscos* mips-*-sysv*
3334 sonymips mips-sony-*
3335 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3337 * REMOVED configurations and files
3339 SGI Irix-4.x mips-sgi-irix4 or iris4
3340 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3341 Z8000 simulator z8k-zilog-none or z8ksim
3342 Matsushita MN10200 w/simulator mn10200-*-*
3343 H8/500 simulator h8500-hitachi-hms or h8500hms
3344 HP/PA running BSD hppa*-*-bsd*
3345 HP/PA running OSF/1 hppa*-*-osf*
3346 HP/PA Pro target hppa*-*-pro*
3347 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3348 386BSD i[3456]86-*-bsd*
3349 Sequent family i[3456]86-sequent-sysv4*
3350 i[3456]86-sequent-sysv*
3351 i[3456]86-sequent-bsd*
3352 SPARC running LynxOS sparc-*-lynxos*
3353 SPARC running SunOS 4 sparc-*-sunos4*
3354 Tsqware Sparclet sparclet-*-*
3355 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3357 *** Changes in GDB 6.0:
3361 Support for debugging the Objective-C programming language has been
3362 integrated into GDB.
3364 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3366 DWARF 2's Call Frame Information makes available compiler generated
3367 information that more exactly describes the program's run-time stack.
3368 By using this information, GDB is able to provide more robust stack
3371 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3372 have been updated to use a new backtrace mechanism which includes
3373 DWARF 2 CFI support.
3377 GDB's remote protocol has been extended to include support for hosted
3378 file I/O (where the remote target uses GDB's file system). See GDB's
3379 remote protocol documentation for details.
3381 * All targets using the new architecture framework.
3383 All of GDB's targets have been updated to use the new internal
3384 architecture framework. The way is now open for future GDB releases
3385 to include cross-architecture native debugging support (i386 on amd64,
3388 * GNU/Linux's Thread Local Storage (TLS)
3390 GDB now includes support for for the GNU/Linux implementation of
3391 per-thread variables.
3393 * GNU/Linux's Native POSIX Thread Library (NPTL)
3395 GDB's thread code has been updated to work with either the new
3396 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3398 * Separate debug info.
3400 GDB, in conjunction with BINUTILS, now supports a mechanism for
3401 automatically loading debug information from a separate file. Instead
3402 of shipping full debug and non-debug versions of system libraries,
3403 system integrators can now instead ship just the stripped libraries
3404 and optional debug files.
3406 * DWARF 2 Location Expressions
3408 DWARF 2 Location Expressions allow the compiler to more completely
3409 describe the location of variables (even in optimized code) to the
3412 GDB now includes preliminary support for location expressions (support
3413 for DW_OP_piece is still missing).
3417 A number of long standing bugs that caused GDB to die while starting a
3418 Java application have been fixed. GDB's Java support is now
3419 considered "useable".
3421 * GNU/Linux support for fork, vfork, and exec.
3423 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3424 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3427 * GDB supports logging output to a file
3429 There are two new commands, "set logging" and "show logging", which can be
3430 used to capture GDB's output to a file.
3432 * The meaning of "detach" has changed for gdbserver
3434 The "detach" command will now resume the application, as documented. To
3435 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3438 * d10v, m68hc11 `regs' command deprecated
3440 The `info registers' command has been updated so that it displays the
3441 registers using a format identical to the old `regs' command.
3445 A new command, "maint set profile on/off", has been added. This command can
3446 be used to enable or disable profiling while running GDB, to profile a
3447 session or a set of commands. In addition there is a new configure switch,
3448 "--enable-profiling", which will cause GDB to be compiled with profiling
3449 data, for more informative profiling results.
3451 * Default MI syntax changed to "mi2".
3453 The default MI (machine interface) syntax, enabled by the command line
3454 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3455 "mi1", can be enabled by specifying the option "-i=mi1".
3457 Support for the original "mi0" syntax (included in GDB 5.0) has been
3460 Fix for gdb/192: removed extraneous space when displaying frame level.
3461 Fix for gdb/672: update changelist is now output in mi list format.
3462 Fix for gdb/702: a -var-assign that updates the value now shows up
3463 in a subsequent -var-update.
3465 * New native configurations.
3467 FreeBSD/amd64 x86_64-*-freebsd*
3469 * Multi-arched targets.
3471 HP/PA HPUX11 hppa*-*-hpux*
3472 Renesas M32R/D w/simulator m32r-*-elf*
3474 * OBSOLETE configurations and files
3476 Configurations that have been declared obsolete in this release have
3477 been commented out. Unless there is activity to revive these
3478 configurations, the next release of GDB will have their sources
3479 permanently REMOVED.
3481 Z8000 simulator z8k-zilog-none or z8ksim
3482 Matsushita MN10200 w/simulator mn10200-*-*
3483 H8/500 simulator h8500-hitachi-hms or h8500hms
3484 HP/PA running BSD hppa*-*-bsd*
3485 HP/PA running OSF/1 hppa*-*-osf*
3486 HP/PA Pro target hppa*-*-pro*
3487 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3488 Sequent family i[3456]86-sequent-sysv4*
3489 i[3456]86-sequent-sysv*
3490 i[3456]86-sequent-bsd*
3491 Tsqware Sparclet sparclet-*-*
3492 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3494 * REMOVED configurations and files
3497 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3498 IBM AIX PS/2 i[3456]86-*-aix
3499 i386 running Mach 3.0 i[3456]86-*-mach3*
3500 i386 running Mach i[3456]86-*-mach*
3501 i386 running OSF/1 i[3456]86-*osf1mk*
3502 HP/Apollo 68k Family m68*-apollo*-sysv*,
3504 m68*-hp-bsd*, m68*-hp-hpux*
3505 Argonaut Risc Chip (ARC) arc-*-*
3506 Mitsubishi D30V d30v-*-*
3507 Fujitsu FR30 fr30-*-elf*
3508 OS/9000 i[34]86-*-os9k
3509 I960 with MON960 i960-*-coff
3511 * MIPS $fp behavior changed
3513 The convenience variable $fp, for the MIPS, now consistently returns
3514 the address of the current frame's base. Previously, depending on the
3515 context, $fp could refer to either $sp or the current frame's base
3516 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3517 The GNU Source-Level Debugger''.
3519 *** Changes in GDB 5.3:
3521 * GNU/Linux shared library multi-threaded performance improved.
3523 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3524 `/proc', in preference to `ptrace' for memory reads. This may result
3525 in an improvement in the start-up time of multi-threaded, shared
3526 library applications when run under GDB. One GDB user writes: ``loads
3527 shared libs like mad''.
3529 * ``gdbserver'' now supports multi-threaded applications on some targets
3531 Support for debugging multi-threaded applications which use
3532 the GNU/Linux LinuxThreads package has been added for
3533 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3534 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3536 * GDB now supports C/C++ preprocessor macros.
3538 GDB now expands preprocessor macro invocations in C/C++ expressions,
3539 and provides various commands for showing macro definitions and how
3542 The new command `macro expand EXPRESSION' expands any macro
3543 invocations in expression, and shows the result.
3545 The new command `show macro MACRO-NAME' shows the definition of the
3546 macro named MACRO-NAME, and where it was defined.
3548 Most compilers don't include information about macros in the debugging
3549 information by default. In GCC 3.1, for example, you need to compile
3550 your program with the options `-gdwarf-2 -g3'. If the macro
3551 information is present in the executable, GDB will read it.
3553 * Multi-arched targets.
3555 DEC Alpha (partial) alpha*-*-*
3556 DEC VAX (partial) vax-*-*
3558 National Semiconductor NS32000 (partial) ns32k-*-*
3559 Motorola 68000 (partial) m68k-*-*
3560 Motorola MCORE mcore-*-*
3564 Fujitsu FRV architecture added by Red Hat frv*-*-*
3567 * New native configurations
3569 Alpha NetBSD alpha*-*-netbsd*
3570 SH NetBSD sh*-*-netbsdelf*
3571 MIPS NetBSD mips*-*-netbsd*
3572 UltraSPARC NetBSD sparc64-*-netbsd*
3574 * OBSOLETE configurations and files
3576 Configurations that have been declared obsolete in this release have
3577 been commented out. Unless there is activity to revive these
3578 configurations, the next release of GDB will have their sources
3579 permanently REMOVED.
3581 Mitsubishi D30V d30v-*-*
3582 OS/9000 i[34]86-*-os9k
3583 IBM AIX PS/2 i[3456]86-*-aix
3584 Fujitsu FR30 fr30-*-elf*
3585 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3586 Argonaut Risc Chip (ARC) arc-*-*
3587 i386 running Mach 3.0 i[3456]86-*-mach3*
3588 i386 running Mach i[3456]86-*-mach*
3589 i386 running OSF/1 i[3456]86-*osf1mk*
3590 HP/Apollo 68k Family m68*-apollo*-sysv*,
3592 m68*-hp-bsd*, m68*-hp-hpux*
3593 I960 with MON960 i960-*-coff
3595 * OBSOLETE languages
3597 CHILL, a Pascal like language used by telecommunications companies.
3599 * REMOVED configurations and files
3601 AMD 29k family via UDI a29k-amd-udi, udi29k
3602 A29K VxWorks a29k-*-vxworks
3603 AMD 29000 embedded, using EBMON a29k-none-none
3604 AMD 29000 embedded with COFF a29k-none-coff
3605 AMD 29000 embedded with a.out a29k-none-aout
3607 testsuite/gdb.hp/gdb.threads-hp/ directory
3609 * New command "set max-user-call-depth <nnn>"
3611 This command allows the user to limit the call depth of user-defined
3612 commands. The default is 1024.
3614 * Changes in FreeBSD/i386 native debugging.
3616 Support for the "generate-core-file" has been added.
3618 * New commands "dump", "append", and "restore".
3620 These commands allow data to be copied from target memory
3621 to a bfd-format or binary file (dump and append), and back
3622 from a file into memory (restore).
3624 * Improved "next/step" support on multi-processor Alpha Tru64.
3626 The previous single-step mechanism could cause unpredictable problems,
3627 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3628 of a software single-step mechanism prevents this.
3630 *** Changes in GDB 5.2.1:
3638 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3639 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3640 Fix, by Joel Brobecker imported from mainline.
3642 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3643 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3644 Fix, by Fred Fish, imported from mainline.
3646 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3647 Surprisingly enough, it works now.
3648 By Michal Ludvig, imported from mainline.
3650 i386 hardware watchpoint support:
3651 avoid misses on second run for some targets.
3652 By Pierre Muller, imported from mainline.
3654 *** Changes in GDB 5.2:
3656 * New command "set trust-readonly-sections on[off]".
3658 This command is a hint that tells gdb that read-only sections
3659 really are read-only (ie. that their contents will not change).
3660 In this mode, gdb will go to the object file rather than the
3661 target to read memory from read-only sections (such as ".text").
3662 This can be a significant performance improvement on some
3663 (notably embedded) targets.
3665 * New command "generate-core-file" (or "gcore").
3667 This new gdb command allows the user to drop a core file of the child
3668 process state at any time. So far it's been implemented only for
3669 GNU/Linux and Solaris, but should be relatively easily ported to other
3670 hosts. Argument is core file name (defaults to core.<pid>).
3672 * New command line option
3674 GDB now accepts --pid or -p followed by a process id.
3676 * Change in command line behavior -- corefiles vs. process ids.
3678 There is a subtle behavior in the way in which GDB handles
3679 command line arguments. The first non-flag argument is always
3680 a program to debug, but the second non-flag argument may either
3681 be a corefile or a process id. Previously, GDB would attempt to
3682 open the second argument as a corefile, and if that failed, would
3683 issue a superfluous error message and then attempt to attach it as
3684 a process. Now, if the second argument begins with a non-digit,
3685 it will be treated as a corefile. If it begins with a digit,
3686 GDB will attempt to attach it as a process, and if no such process
3687 is found, will then attempt to open it as a corefile.
3689 * Changes in ARM configurations.
3691 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3692 configuration is fully multi-arch.
3694 * New native configurations
3696 ARM NetBSD arm*-*-netbsd*
3697 x86 OpenBSD i[3456]86-*-openbsd*
3698 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3699 Sparc64 running FreeBSD sparc64-*-freebsd*
3703 Sanyo XStormy16 xstormy16-elf
3705 * OBSOLETE configurations and files
3707 Configurations that have been declared obsolete in this release have
3708 been commented out. Unless there is activity to revive these
3709 configurations, the next release of GDB will have their sources
3710 permanently REMOVED.
3712 AMD 29k family via UDI a29k-amd-udi, udi29k
3713 A29K VxWorks a29k-*-vxworks
3714 AMD 29000 embedded, using EBMON a29k-none-none
3715 AMD 29000 embedded with COFF a29k-none-coff
3716 AMD 29000 embedded with a.out a29k-none-aout
3718 testsuite/gdb.hp/gdb.threads-hp/ directory
3720 * REMOVED configurations and files
3722 TI TMS320C80 tic80-*-*
3724 PowerPC Solaris powerpcle-*-solaris*
3725 PowerPC Windows NT powerpcle-*-cygwin32
3726 PowerPC Netware powerpc-*-netware*
3727 Harris/CXUX m88k m88*-harris-cxux*
3728 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3729 ns32k-utek-sysv* ns32k-utek-*
3730 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3731 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3732 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3733 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3734 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3736 * Changes to command line processing
3738 The new `--args' feature can be used to specify command-line arguments
3739 for the inferior from gdb's command line.
3741 * Changes to key bindings
3743 There is a new `operate-and-get-next' function bound to `C-o'.
3745 *** Changes in GDB 5.1.1
3747 Fix compile problem on DJGPP.
3749 Fix a problem with floating-point registers on the i386 being
3752 Fix to stop GDB crashing on .debug_str debug info.
3754 Numerous documentation fixes.
3756 Numerous testsuite fixes.
3758 *** Changes in GDB 5.1:
3760 * New native configurations
3762 Alpha FreeBSD alpha*-*-freebsd*
3763 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3764 MIPS GNU/Linux mips*-*-linux*
3765 MIPS SGI Irix 6.x mips*-sgi-irix6*
3766 ia64 AIX ia64-*-aix*
3767 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3771 Motorola 68HC11 and 68HC12 m68hc11-elf
3773 UltraSparc running GNU/Linux sparc64-*-linux*
3775 * OBSOLETE configurations and files
3777 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3778 Harris/CXUX m88k m88*-harris-cxux*
3779 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3780 ns32k-utek-sysv* ns32k-utek-*
3781 TI TMS320C80 tic80-*-*
3783 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3784 PowerPC Solaris powerpcle-*-solaris*
3785 PowerPC Windows NT powerpcle-*-cygwin32
3786 PowerPC Netware powerpc-*-netware*
3787 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3788 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3789 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3790 Apple Macintosh (MPW) host N/A
3792 stuff.c (Program to stuff files into a specially prepared space in kdb)
3793 kdb-start.c (Main loop for the standalone kernel debugger)
3795 Configurations that have been declared obsolete in this release have
3796 been commented out. Unless there is activity to revive these
3797 configurations, the next release of GDB will have their sources
3798 permanently REMOVED.
3800 * REMOVED configurations and files
3802 Altos 3068 m68*-altos-*
3803 Convex c1-*-*, c2-*-*
3805 ARM RISCix arm-*-* (as host)
3809 * GDB has been converted to ISO C.
3811 GDB's source code has been converted to ISO C. In particular, the
3812 sources are fully protoized, and rely on standard headers being
3817 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3819 * The MI enabled by default.
3821 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3822 revised and enabled by default. Packages which use GDB as a debugging
3823 engine behind a UI or another front end are encouraged to switch to
3824 using the GDB/MI interface, instead of the old annotations interface
3825 which is now deprecated.
3827 * Support for debugging Pascal programs.
3829 GDB now includes support for debugging Pascal programs. The following
3830 main features are supported:
3832 - Pascal-specific data types such as sets;
3834 - automatic recognition of Pascal sources based on file-name
3837 - Pascal-style display of data types, variables, and functions;
3839 - a Pascal expression parser.
3841 However, some important features are not yet supported.
3843 - Pascal string operations are not supported at all;
3845 - there are some problems with boolean types;
3847 - Pascal type hexadecimal constants are not supported
3848 because they conflict with the internal variables format;
3850 - support for Pascal objects and classes is not full yet;
3852 - unlike Pascal, GDB is case-sensitive for symbol names.
3854 * Changes in completion.
3856 Commands such as `shell', `run' and `set args', which pass arguments
3857 to inferior programs, now complete on file names, similar to what
3858 users expect at the shell prompt.
3860 Commands which accept locations, such as `disassemble', `print',
3861 `breakpoint', `until', etc. now complete on filenames as well as
3862 program symbols. Thus, if you type "break foob TAB", and the source
3863 files linked into the programs include `foobar.c', that file name will
3864 be one of the candidates for completion. However, file names are not
3865 considered for completion after you typed a colon that delimits a file
3866 name from a name of a function in that file, as in "break foo.c:bar".
3868 `set demangle-style' completes on available demangling styles.
3870 * New platform-independent commands:
3872 It is now possible to define a post-hook for a command as well as a
3873 hook that runs before the command. For more details, see the
3874 documentation of `hookpost' in the GDB manual.
3876 * Changes in GNU/Linux native debugging.
3878 Support for debugging multi-threaded programs has been completely
3879 revised for all platforms except m68k and sparc. You can now debug as
3880 many threads as your system allows you to have.
3882 Attach/detach is supported for multi-threaded programs.
3884 Support for SSE registers was added for x86. This doesn't work for
3885 multi-threaded programs though.
3887 * Changes in MIPS configurations.
3889 Multi-arch support is enabled for all MIPS configurations.
3891 GDB can now be built as native debugger on SGI Irix 6.x systems for
3892 debugging n32 executables. (Debugging 64-bit executables is not yet
3895 * Unified support for hardware watchpoints in all x86 configurations.
3897 Most (if not all) native x86 configurations support hardware-assisted
3898 breakpoints and watchpoints in a unified manner. This support
3899 implements debug register sharing between watchpoints, which allows to
3900 put a virtually infinite number of watchpoints on the same address,
3901 and also supports watching regions up to 16 bytes with several debug
3904 The new maintenance command `maintenance show-debug-regs' toggles
3905 debugging print-outs in functions that insert, remove, and test
3906 watchpoints and hardware breakpoints.
3908 * Changes in the DJGPP native configuration.
3910 New command ``info dos sysinfo'' displays assorted information about
3911 the CPU, OS, memory, and DPMI server.
3913 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3914 display information about segment descriptors stored in GDT, LDT, and
3917 New commands ``info dos pde'' and ``info dos pte'' display entries
3918 from Page Directory and Page Tables (for now works with CWSDPMI only).
3919 New command ``info dos address-pte'' displays the Page Table entry for
3920 a given linear address.
3922 GDB can now pass command lines longer than 126 characters to the
3923 program being debugged (requires an update to the libdbg.a library
3924 which is part of the DJGPP development kit).
3926 DWARF2 debug info is now supported.
3928 It is now possible to `step' and `next' through calls to `longjmp'.
3930 * Changes in documentation.
3932 All GDB documentation was converted to GFDL, the GNU Free
3933 Documentation License.
3935 Tracepoints-related commands are now fully documented in the GDB
3938 TUI, the Text-mode User Interface, is now documented in the manual.
3940 Tracepoints-related commands are now fully documented in the GDB
3943 The "GDB Internals" manual now has an index. It also includes
3944 documentation of `ui_out' functions, GDB coding standards, x86
3945 hardware watchpoints, and memory region attributes.
3947 * GDB's version number moved to ``version.in''
3949 The Makefile variable VERSION has been replaced by the file
3950 ``version.in''. People creating GDB distributions should update the
3951 contents of this file.
3955 GUD support is now a standard part of the EMACS distribution.
3957 *** Changes in GDB 5.0:
3959 * Improved support for debugging FP programs on x86 targets
3961 Unified and much-improved support for debugging floating-point
3962 programs on all x86 targets. In particular, ``info float'' now
3963 displays the FP registers in the same format on all x86 targets, with
3964 greater level of detail.
3966 * Improvements and bugfixes in hardware-assisted watchpoints
3968 It is now possible to watch array elements, struct members, and
3969 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3970 on x86 targets no longer erroneously trigger when the address is
3973 * Improvements in the native DJGPP version of GDB
3975 The distribution now includes all the scripts and auxiliary files
3976 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3977 machines ``out of the box''.
3979 The DJGPP version can now debug programs that use signals. It is
3980 possible to catch signals that happened in the debuggee, deliver
3981 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3982 would kill the program being debugged.) Programs that hook hardware
3983 interrupts (keyboard, timer, etc.) can also be debugged.
3985 It is now possible to debug DJGPP programs that redirect their
3986 standard handles or switch them to raw (as opposed to cooked) mode, or
3987 even close them. The command ``run < foo > bar'' works as expected,
3988 and ``info terminal'' reports useful information about the debuggee's
3989 terminal, including raw/cooked mode, redirection, etc.
3991 The DJGPP version now uses termios functions for console I/O, which
3992 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3995 DOS-style file names with drive letters are now fully supported by
3998 It is now possible to debug DJGPP programs that switch their working
3999 directory. It is also possible to rerun the debuggee any number of
4000 times without restarting GDB; thus, you can use the same setup,
4001 breakpoints, etc. for many debugging sessions.
4003 * New native configurations
4005 ARM GNU/Linux arm*-*-linux*
4006 PowerPC GNU/Linux powerpc-*-linux*
4010 Motorola MCore mcore-*-*
4011 x86 VxWorks i[3456]86-*-vxworks*
4012 PowerPC VxWorks powerpc-*-vxworks*
4013 TI TMS320C80 tic80-*-*
4015 * OBSOLETE configurations
4017 Altos 3068 m68*-altos-*
4018 Convex c1-*-*, c2-*-*
4020 ARM RISCix arm-*-* (as host)
4023 Configurations that have been declared obsolete will be commented out,
4024 but the code will be left in place. If there is no activity to revive
4025 these configurations before the next release of GDB, the sources will
4026 be permanently REMOVED.
4028 * Gould support removed
4030 Support for the Gould PowerNode and NP1 has been removed.
4032 * New features for SVR4
4034 On SVR4 native platforms (such as Solaris), if you attach to a process
4035 without first loading a symbol file, GDB will now attempt to locate and
4036 load symbols from the running process's executable file.
4038 * Many C++ enhancements
4040 C++ support has been greatly improved. Overload resolution now works properly
4041 in almost all cases. RTTI support is on the way.
4043 * Remote targets can connect to a sub-program
4045 A popen(3) style serial-device has been added. This device starts a
4046 sub-process (such as a stand-alone simulator) and then communicates
4047 with that. The sub-program to run is specified using the syntax
4048 ``|<program> <args>'' vis:
4050 (gdb) set remotedebug 1
4051 (gdb) target extended-remote |mn10300-elf-sim program-args
4053 * MIPS 64 remote protocol
4055 A long standing bug in the mips64 remote protocol where by GDB
4056 expected certain 32 bit registers (ex SR) to be transfered as 32
4057 instead of 64 bits has been fixed.
4059 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4060 added to provide backward compatibility with older versions of GDB.
4062 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4064 The command ``set remotebinarydownload'' command has been replaced by
4065 ``set remote X-packet''. Other commands in ``set remote'' family
4066 include ``set remote P-packet''.
4068 * Breakpoint commands accept ranges.
4070 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4071 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4072 ``tracepoint passcount'' also accepts a range of tracepoints.
4074 * ``apropos'' command added.
4076 The ``apropos'' command searches through command names and
4077 documentation strings, printing out matches, making it much easier to
4078 try to find a command that does what you are looking for.
4082 A new machine oriented interface (MI) has been added to GDB. This
4083 interface is designed for debug environments running GDB as a separate
4084 process. This is part of the long term libGDB project. See the
4085 "GDB/MI" chapter of the GDB manual for further information. It can be
4086 enabled by configuring with:
4088 .../configure --enable-gdbmi
4090 *** Changes in GDB-4.18:
4092 * New native configurations
4094 HP-UX 10.20 hppa*-*-hpux10.20
4095 HP-UX 11.x hppa*-*-hpux11.0*
4096 M68K GNU/Linux m68*-*-linux*
4100 Fujitsu FR30 fr30-*-elf*
4101 Intel StrongARM strongarm-*-*
4102 Mitsubishi D30V d30v-*-*
4104 * OBSOLETE configurations
4106 Gould PowerNode, NP1 np1-*-*, pn-*-*
4108 Configurations that have been declared obsolete will be commented out,
4109 but the code will be left in place. If there is no activity to revive
4110 these configurations before the next release of GDB, the sources will
4111 be permanently REMOVED.
4115 As a compatibility experiment, GDB's source files buildsym.h and
4116 buildsym.c have been converted to pure standard C, no longer
4117 containing any K&R compatibility code. We believe that all systems in
4118 use today either come with a standard C compiler, or have a GCC port
4119 available. If this is not true, please report the affected
4120 configuration to bug-gdb@gnu.org immediately. See the README file for
4121 information about getting a standard C compiler if you don't have one
4126 GDB now uses readline 2.2.
4128 * set extension-language
4130 You can now control the mapping between filename extensions and source
4131 languages by using the `set extension-language' command. For instance,
4132 you can ask GDB to treat .c files as C++ by saying
4133 set extension-language .c c++
4134 The command `info extensions' lists all of the recognized extensions
4135 and their associated languages.
4137 * Setting processor type for PowerPC and RS/6000
4139 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4140 you can use the `set processor' command to specify what variant of the
4141 PowerPC family you are debugging. The command
4145 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4146 following PowerPC and RS6000 variants:
4148 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4149 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4151 403GC IBM PowerPC 403GC
4152 505 Motorola PowerPC 505
4153 860 Motorola PowerPC 860 or 850
4154 601 Motorola PowerPC 601
4155 602 Motorola PowerPC 602
4156 603 Motorola/IBM PowerPC 603 or 603e
4157 604 Motorola PowerPC 604 or 604e
4158 750 Motorola/IBM PowerPC 750 or 750
4160 At the moment, this command just tells GDB what to name the
4161 special-purpose processor registers. Since almost all the affected
4162 registers are inaccessible to user-level programs, this command is
4163 only useful for remote debugging in its present form.
4167 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4168 more extensive support for HP-UX. Added features include shared
4169 library support, kernel threads and hardware watchpoints for 11.00,
4170 support for HP's ANSI C and C++ compilers, and a compatibility mode
4171 for xdb and dbx commands.
4175 HP's donation includes the new concept of catchpoints, which is a
4176 generalization of the old catch command. On HP-UX, it is now possible
4177 to catch exec, fork, and vfork, as well as library loading.
4179 This means that the existing catch command has changed; its first
4180 argument now specifies the type of catch to be set up. See the
4181 output of "help catch" for a list of catchpoint types.
4183 * Debugging across forks
4185 On HP-UX, you can choose which process to debug when a fork() happens
4190 HP has donated a curses-based terminal user interface (TUI). To get
4191 it, build with --enable-tui. Although this can be enabled for any
4192 configuration, at present it only works for native HP debugging.
4194 * GDB remote protocol additions
4196 A new protocol packet 'X' that writes binary data is now available.
4197 Default behavior is to try 'X', then drop back to 'M' if the stub
4198 fails to respond. The settable variable `remotebinarydownload'
4199 allows explicit control over the use of 'X'.
4201 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4202 full 64-bit address. The command
4204 set remoteaddresssize 32
4206 can be used to revert to the old behaviour. For existing remote stubs
4207 the change should not be noticed, as the additional address information
4210 In order to assist in debugging stubs, you may use the maintenance
4211 command `packet' to send any text string to the stub. For instance,
4213 maint packet heythere
4215 sends the packet "$heythere#<checksum>". Note that it is very easy to
4216 disrupt a debugging session by sending the wrong packet at the wrong
4219 The compare-sections command allows you to compare section data on the
4220 target to what is in the executable file without uploading or
4221 downloading, by comparing CRC checksums.
4223 * Tracing can collect general expressions
4225 You may now collect general expressions at tracepoints. This requires
4226 further additions to the target-side stub; see tracepoint.c and
4227 doc/agentexpr.texi for further details.
4229 * mask-address variable for Mips
4231 For Mips targets, you may control the zeroing of the upper 32 bits of
4232 a 64-bit address by entering `set mask-address on'. This is mainly
4233 of interest to users of embedded R4xxx and R5xxx processors.
4235 * Higher serial baud rates
4237 GDB's serial code now allows you to specify baud rates 57600, 115200,
4238 230400, and 460800 baud. (Note that your host system may not be able
4239 to achieve all of these rates.)
4243 The i960 configuration now includes an initial implementation of a
4244 builtin simulator, contributed by Jim Wilson.
4247 *** Changes in GDB-4.17:
4249 * New native configurations
4251 Alpha GNU/Linux alpha*-*-linux*
4252 Unixware 2.x i[3456]86-unixware2*
4253 Irix 6.x mips*-sgi-irix6*
4254 PowerPC GNU/Linux powerpc-*-linux*
4255 PowerPC Solaris powerpcle-*-solaris*
4256 Sparc GNU/Linux sparc-*-linux*
4257 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4261 Argonaut Risc Chip (ARC) arc-*-*
4262 Hitachi H8/300S h8300*-*-*
4263 Matsushita MN10200 w/simulator mn10200-*-*
4264 Matsushita MN10300 w/simulator mn10300-*-*
4265 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4266 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4267 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4268 Mitsubishi D10V w/simulator d10v-*-*
4269 Mitsubishi M32R/D w/simulator m32r-*-elf*
4270 Tsqware Sparclet sparclet-*-*
4271 NEC V850 w/simulator v850-*-*
4273 * New debugging protocols
4275 ARM with RDI protocol arm*-*-*
4276 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4277 DDB and LSI variants of PMON protocol mips*-*-*
4278 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4279 PowerPC with SDS protocol powerpc{,le}-*-eabi
4280 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4284 All configurations can now understand and use the DWARF 2 debugging
4285 format. The choice is automatic, if the symbol file contains DWARF 2
4290 GDB now includes basic Java language support. This support is
4291 only useful with Java compilers that produce native machine code.
4293 * solib-absolute-prefix and solib-search-path
4295 For SunOS and SVR4 shared libraries, you may now set the prefix for
4296 loading absolute shared library symbol files, and the search path for
4297 locating non-absolute shared library symbol files.
4299 * Live range splitting
4301 GDB can now effectively debug code for which GCC has performed live
4302 range splitting as part of its optimization. See gdb/doc/LRS for
4303 more details on the expected format of the stabs information.
4307 GDB's support for the GNU Hurd, including thread debugging, has been
4308 updated to work with current versions of the Hurd.
4312 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4313 instruction set. ARM GDB automatically detects when Thumb
4314 instructions are in use, and adjusts disassembly and backtracing
4319 GDB's MIPS target configurations now handle the MIP16 16-bit
4324 GDB now includes support for overlays; if an executable has been
4325 linked such that multiple sections are based at the same address, GDB
4326 will decide which section to use for symbolic info. You can choose to
4327 control the decision manually, using overlay commands, or implement
4328 additional target-side support and use "overlay load-target" to bring
4329 in the overlay mapping. Do "help overlay" for more detail.
4333 The command "info symbol <address>" displays information about
4334 the symbol at the specified address.
4338 The standard remote protocol now includes an extension that allows
4339 asynchronous collection and display of trace data. This requires
4340 extensive support in the target-side debugging stub. Tracing mode
4341 includes a new interaction mode in GDB and new commands: see the
4342 file tracepoint.c for more details.
4346 Configurations for embedded MIPS now include a simulator contributed
4347 by Cygnus Solutions. The simulator supports the instruction sets
4348 of most MIPS variants.
4352 Sparc configurations may now include the ERC32 simulator contributed
4353 by the European Space Agency. The simulator is not built into
4354 Sparc targets by default; configure with --enable-sim to include it.
4358 For target configurations that may include multiple variants of a
4359 basic architecture (such as MIPS and SH), you may now set the
4360 architecture explicitly. "set arch" sets, "info arch" lists
4361 the possible architectures.
4363 *** Changes in GDB-4.16:
4365 * New native configurations
4367 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4368 M68K NetBSD m68k-*-netbsd*
4369 PowerPC AIX 4.x powerpc-*-aix*
4370 PowerPC MacOS powerpc-*-macos*
4371 PowerPC Windows NT powerpcle-*-cygwin32
4372 RS/6000 AIX 4.x rs6000-*-aix4*
4376 ARM with RDP protocol arm-*-*
4377 I960 with MON960 i960-*-coff
4378 MIPS VxWorks mips*-*-vxworks*
4379 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4380 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4382 Matra Sparclet sparclet-*-*
4386 The powerpc-eabi configuration now includes the PSIM simulator,
4387 contributed by Andrew Cagney, with assistance from Mike Meissner.
4388 PSIM is a very elaborate model of the PowerPC, including not only
4389 basic instruction set execution, but also details of execution unit
4390 performance and I/O hardware. See sim/ppc/README for more details.
4394 GDB now works with Solaris 2.5.
4396 * Windows 95/NT native
4398 GDB will now work as a native debugger on Windows 95 and Windows NT.
4399 To build it from source, you must use the "gnu-win32" environment,
4400 which uses a DLL to emulate enough of Unix to run the GNU tools.
4401 Further information, binaries, and sources are available at
4402 ftp.cygnus.com, under pub/gnu-win32.
4404 * dont-repeat command
4406 If a user-defined command includes the command `dont-repeat', then the
4407 command will not be repeated if the user just types return. This is
4408 useful if the command is time-consuming to run, so that accidental
4409 extra keystrokes don't run the same command many times.
4411 * Send break instead of ^C
4413 The standard remote protocol now includes an option to send a break
4414 rather than a ^C to the target in order to interrupt it. By default,
4415 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4417 * Remote protocol timeout
4419 The standard remote protocol includes a new variable `remotetimeout'
4420 that allows you to set the number of seconds before GDB gives up trying
4421 to read from the target. The default value is 2.
4423 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4425 By default GDB will automatically keep track of objects as they are
4426 loaded and unloaded by the dynamic linker. By using the command `set
4427 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4428 when shared library events occur, thus allowing you to set breakpoints
4429 in shared libraries which are explicitly loaded by the inferior.
4431 Note this feature does not work on hpux8. On hpux9 you must link
4432 /usr/lib/end.o into your program. This feature should work
4433 automatically on hpux10.
4435 * Irix 5.x hardware watchpoint support
4437 Irix 5 configurations now support the use of hardware watchpoints.
4439 * Mips protocol "SYN garbage limit"
4441 When debugging a Mips target using the `target mips' protocol, you
4442 may set the number of characters that GDB will ignore by setting
4443 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4444 every character. The default value is 1050.
4446 * Recording and replaying remote debug sessions
4448 If you set `remotelogfile' to the name of a file, gdb will write to it
4449 a recording of a remote debug session. This recording may then be
4450 replayed back to gdb using "gdbreplay". See gdbserver/README for
4451 details. This is useful when you have a problem with GDB while doing
4452 remote debugging; you can make a recording of the session and send it
4453 to someone else, who can then recreate the problem.
4455 * Speedups for remote debugging
4457 GDB includes speedups for downloading and stepping MIPS systems using
4458 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4459 and more efficient S-record downloading.
4461 * Memory use reductions and statistics collection
4463 GDB now uses less memory and reports statistics about memory usage.
4464 Try the `maint print statistics' command, for example.
4466 *** Changes in GDB-4.15:
4468 * Psymtabs for XCOFF
4470 The symbol reader for AIX GDB now uses partial symbol tables. This
4471 can greatly improve startup time, especially for large executables.
4473 * Remote targets use caching
4475 Remote targets now use a data cache to speed up communication with the
4476 remote side. The data cache could lead to incorrect results because
4477 it doesn't know about volatile variables, thus making it impossible to
4478 debug targets which use memory mapped I/O devices. `set remotecache
4479 off' turns the the data cache off.
4481 * Remote targets may have threads
4483 The standard remote protocol now includes support for multiple threads
4484 in the target system, using new protocol commands 'H' and 'T'. See
4485 gdb/remote.c for details.
4489 If GDB is configured with `--enable-netrom', then it will include
4490 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4491 acts as though it is a bank of ROM on the target board, but you can
4492 write into it over the network. GDB's support consists only of
4493 support for fast loading into the emulated ROM; to debug, you must use
4494 another protocol, such as standard remote protocol. The usual
4495 sequence is something like
4497 target nrom <netrom-hostname>
4499 target remote <netrom-hostname>:1235
4503 GDB now includes support for the Apple Macintosh, as a host only. It
4504 may be run as either an MPW tool or as a standalone application, and
4505 it can debug through the serial port. All the usual GDB commands are
4506 available, but to the target command, you must supply "serial" as the
4507 device type instead of "/dev/ttyXX". See mpw-README in the main
4508 directory for more information on how to build. The MPW configuration
4509 scripts */mpw-config.in support only a few targets, and only the
4510 mips-idt-ecoff target has been tested.
4514 GDB configuration now uses autoconf. This is not user-visible,
4515 but does simplify configuration and building.
4519 GDB now supports hpux10.
4521 *** Changes in GDB-4.14:
4523 * New native configurations
4525 x86 FreeBSD i[345]86-*-freebsd
4526 x86 NetBSD i[345]86-*-netbsd
4527 NS32k NetBSD ns32k-*-netbsd
4528 Sparc NetBSD sparc-*-netbsd
4532 A29K VxWorks a29k-*-vxworks
4533 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4534 CPU32 EST-300 emulator m68*-*-est*
4535 PowerPC ELF powerpc-*-elf
4538 * Alpha OSF/1 support for procfs
4540 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4541 possible to attach to running processes. As the mounting of the /proc
4542 filesystem is optional on the Alpha, GDB automatically determines
4543 the availability of /proc during startup. This can lead to problems
4544 if /proc is unmounted after GDB has been started.
4546 * Arguments to user-defined commands
4548 User commands may accept up to 10 arguments separated by whitespace.
4549 Arguments are accessed within the user command via $arg0..$arg9. A
4552 print $arg0 + $arg1 + $arg2
4554 To execute the command use:
4557 Defines the command "adder" which prints the sum of its three arguments.
4558 Note the arguments are text substitutions, so they may reference variables,
4559 use complex expressions, or even perform inferior function calls.
4561 * New `if' and `while' commands
4563 This makes it possible to write more sophisticated user-defined
4564 commands. Both commands take a single argument, which is the
4565 expression to evaluate, and must be followed by the commands to
4566 execute, one per line, if the expression is nonzero, the list being
4567 terminated by the word `end'. The `if' command list may include an
4568 `else' word, which causes the following commands to be executed only
4569 if the expression is zero.
4571 * Fortran source language mode
4573 GDB now includes partial support for Fortran 77. It will recognize
4574 Fortran programs and can evaluate a subset of Fortran expressions, but
4575 variables and functions may not be handled correctly. GDB will work
4576 with G77, but does not yet know much about symbols emitted by other
4579 * Better HPUX support
4581 Most debugging facilities now work on dynamic executables for HPPAs
4582 running hpux9 or later. You can attach to running dynamically linked
4583 processes, but by default the dynamic libraries will be read-only, so
4584 for instance you won't be able to put breakpoints in them. To change
4585 that behavior do the following before running the program:
4591 This will cause the libraries to be mapped private and read-write.
4592 To revert to the normal behavior, do this:
4598 You cannot set breakpoints or examine data in the library until after
4599 the library is loaded if the function/data symbols do not have
4602 GDB can now also read debug symbols produced by the HP C compiler on
4603 HPPAs (sorry, no C++, Fortran or 68k support).
4605 * Target byte order now dynamically selectable
4607 You can choose which byte order to use with a target system, via the
4608 commands "set endian big" and "set endian little", and you can see the
4609 current setting by using "show endian". You can also give the command
4610 "set endian auto", in which case GDB will use the byte order
4611 associated with the executable. Currently, only embedded MIPS
4612 configurations support dynamic selection of target byte order.
4614 * New DOS host serial code
4616 This version uses DPMI interrupts to handle buffered I/O, so you
4617 no longer need to run asynctsr when debugging boards connected to
4620 *** Changes in GDB-4.13:
4622 * New "complete" command
4624 This lists all the possible completions for the rest of the line, if it
4625 were to be given as a command itself. This is intended for use by emacs.
4627 * Trailing space optional in prompt
4629 "set prompt" no longer adds a space for you after the prompt you set. This
4630 allows you to set a prompt which ends in a space or one that does not.
4632 * Breakpoint hit counts
4634 "info break" now displays a count of the number of times the breakpoint
4635 has been hit. This is especially useful in conjunction with "ignore"; you
4636 can ignore a large number of breakpoint hits, look at the breakpoint info
4637 to see how many times the breakpoint was hit, then run again, ignoring one
4638 less than that number, and this will get you quickly to the last hit of
4641 * Ability to stop printing at NULL character
4643 "set print null-stop" will cause GDB to stop printing the characters of
4644 an array when the first NULL is encountered. This is useful when large
4645 arrays actually contain only short strings.
4647 * Shared library breakpoints
4649 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4650 breakpoints in shared libraries before the executable is run.
4652 * Hardware watchpoints
4654 There is a new hardware breakpoint for the watch command for sparclite
4655 targets. See gdb/sparclite/hw_breakpoint.note.
4657 Hardware watchpoints are also now supported under GNU/Linux.
4661 Annotations have been added. These are for use with graphical interfaces,
4662 and are still experimental. Currently only gdba.el uses these.
4664 * Improved Irix 5 support
4666 GDB now works properly with Irix 5.2.
4668 * Improved HPPA support
4670 GDB now works properly with the latest GCC and GAS.
4672 * New native configurations
4674 Sequent PTX4 i[34]86-sequent-ptx4
4675 HPPA running OSF/1 hppa*-*-osf*
4676 Atari TT running SVR4 m68*-*-sysv4*
4677 RS/6000 LynxOS rs6000-*-lynxos*
4681 OS/9000 i[34]86-*-os9k
4682 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4685 * Hitachi SH7000 and E7000-PC ICE support
4687 There is now support for communicating with the Hitachi E7000-PC ICE.
4688 This is available automatically when GDB is configured for the SH.
4692 As usual, a variety of small fixes and improvements, both generic
4693 and configuration-specific. See the ChangeLog for more detail.
4695 *** Changes in GDB-4.12:
4697 * Irix 5 is now supported
4701 GDB-4.12 on the HPPA has a number of changes which make it unable
4702 to debug the output from the currently released versions of GCC and
4703 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4704 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4705 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4708 *** Changes in GDB-4.11:
4710 * User visible changes:
4714 The "set remotedebug" option is now consistent between the mips remote
4715 target, remote targets using the gdb-specific protocol, UDI (AMD's
4716 debug protocol for the 29k) and the 88k bug monitor. It is now an
4717 integer specifying a debug level (normally 0 or 1, but 2 means more
4718 debugging info for the mips target).
4720 * DEC Alpha native support
4722 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4723 debug info, but GDB works fairly well with the DEC compiler and should
4724 work with a future GCC release. See the README file for a few
4725 Alpha-specific notes.
4727 * Preliminary thread implementation
4729 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4731 * LynxOS native and target support for 386
4733 This release has been hosted on LynxOS 2.2, and also can be configured
4734 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4737 * Improvements in C++ mangling/demangling.
4739 This release has much better g++ debugging, specifically in name
4740 mangling/demangling, virtual function calls, print virtual table,
4741 call methods, ...etc.
4743 *** Changes in GDB-4.10:
4745 * User visible changes:
4747 Remote debugging using the GDB-specific (`target remote') protocol now
4748 supports the `load' command. This is only useful if you have some
4749 other way of getting the stub to the target system, and you can put it
4750 somewhere in memory where it won't get clobbered by the download.
4752 Filename completion now works.
4754 When run under emacs mode, the "info line" command now causes the
4755 arrow to point to the line specified. Also, "info line" prints
4756 addresses in symbolic form (as well as hex).
4758 All vxworks based targets now support a user settable option, called
4759 vxworks-timeout. This option represents the number of seconds gdb
4760 should wait for responses to rpc's. You might want to use this if
4761 your vxworks target is, perhaps, a slow software simulator or happens
4762 to be on the far side of a thin network line.
4766 This release contains support for using a DEC alpha as a GDB host for
4767 cross debugging. Native alpha debugging is not supported yet.
4770 *** Changes in GDB-4.9:
4774 This is the first GDB release which is accompanied by a matching testsuite.
4775 The testsuite requires installation of dejagnu, which should be available
4776 via ftp from most sites that carry GNU software.
4780 'Cfront' style demangling has had its name changed to 'ARM' style, to
4781 emphasize that it was written from the specifications in the C++ Annotated
4782 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4783 disclaimers, it still generated too much confusion with users attempting to
4784 use gdb with AT&T cfront.
4788 GDB now uses a standard remote interface to a simulator library.
4789 So far, the library contains simulators for the Zilog Z8001/2, the
4790 Hitachi H8/300, H8/500 and Super-H.
4792 * New targets supported
4794 H8/300 simulator h8300-hitachi-hms or h8300hms
4795 H8/500 simulator h8500-hitachi-hms or h8500hms
4796 SH simulator sh-hitachi-hms or sh
4797 Z8000 simulator z8k-zilog-none or z8ksim
4798 IDT MIPS board over serial line mips-idt-ecoff
4800 Cross-debugging to GO32 targets is supported. It requires a custom
4801 version of the i386-stub.c module which is integrated with the
4802 GO32 memory extender.
4804 * New remote protocols
4806 MIPS remote debugging protocol.
4808 * New source languages supported
4810 This version includes preliminary support for Chill, a Pascal like language
4811 used by telecommunications companies. Chill support is also being integrated
4812 into the GNU compiler, but we don't know when it will be publically available.
4815 *** Changes in GDB-4.8:
4817 * HP Precision Architecture supported
4819 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4820 version of this support was available as a set of patches from the
4821 University of Utah. GDB does not support debugging of programs
4822 compiled with the HP compiler, because HP will not document their file
4823 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4824 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4826 Many problems in the preliminary version have been fixed.
4828 * Faster and better demangling
4830 We have improved template demangling and fixed numerous bugs in the GNU style
4831 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4832 character types (wchar_t) are now supported. Demangling of each symbol is now
4833 only done once, and is cached when the symbol table for a file is read in.
4834 This results in a small increase in memory usage for C programs, a moderate
4835 increase in memory usage for C++ programs, and a fantastic speedup in
4838 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4839 from the specifications in the Annotated Reference Manual, which AT&T's
4840 compiler does not actually implement.
4842 * G++ multiple inheritance compiler problem
4844 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4845 inheritance lattices was reworked to properly discover ambiguities. We
4846 recently found an example which causes this new algorithm to fail in a
4847 very subtle way, producing bad debug information for those classes.
4848 The file 'gcc.patch' (in this directory) can be applied to gcc to
4849 circumvent the problem. A future GCC release will contain a complete
4852 The previous G++ debug info problem (mentioned below for the gdb-4.7
4853 release) is fixed in gcc version 2.3.2.
4855 * Improved configure script
4857 The `configure' script will now attempt to guess your system type if
4858 you don't supply a host system type. The old scheme of supplying a
4859 host system triplet is preferable over using this. All the magic is
4860 done in the new `config.guess' script. Examine it for details.
4862 We have also brought our configure script much more in line with the FSF's
4863 version. It now supports the --with-xxx options. In particular,
4864 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4865 The resulting GDB will not be able to read arbitrary object file formats --
4866 only the format ``expected'' to be used on the configured target system.
4867 We hope to make this the default in a future release.
4869 * Documentation improvements
4871 There's new internal documentation on how to modify GDB, and how to
4872 produce clean changes to the code. We implore people to read it
4873 before submitting changes.
4875 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4876 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4877 `info' files are also provided. To build `info' files from scratch,
4878 you will need the latest `makeinfo' release, which will be available in
4879 a future texinfo-X.Y release.
4881 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4882 We're not sure exactly which versions have this problem, but it has
4883 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4884 or better. If that isn't possible, there is a patch in
4885 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4886 around this problem.
4890 GDB now supports array constants that can be used in expressions typed in by
4891 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4892 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4895 The new directory `gdb/sparclite' contains a program that demonstrates
4896 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4898 * New native hosts supported
4900 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4901 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4903 * New targets supported
4905 AMD 29k family via UDI a29k-amd-udi or udi29k
4907 * New file formats supported
4909 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4910 HPUX core files, and SCO 3.2v2 core files.
4914 Attaching to processes now works again; thanks for the many bug reports.
4916 We have also stomped on a bunch of core dumps caused by
4917 printf_filtered("%s") problems.
4919 We eliminated a copyright problem on the rpc and ptrace header files
4920 for VxWorks, which was discovered at the last minute during the 4.7
4921 release. You should now be able to build a VxWorks GDB.
4923 You can now interrupt gdb while an attached process is running. This
4924 will cause the attached process to stop, and give control back to GDB.
4926 We fixed problems caused by using too many file descriptors
4927 for reading symbols from object files and libraries. This was
4928 especially a problem for programs that used many (~100) shared
4931 The `step' command now only enters a subroutine if there is line number
4932 information for the subroutine. Otherwise it acts like the `next'
4933 command. Previously, `step' would enter subroutines if there was
4934 any debugging information about the routine. This avoids problems
4935 when using `cc -g1' on MIPS machines.
4937 * Internal improvements
4939 GDB's internal interfaces have been improved to make it easier to support
4940 debugging of multiple languages in the future.
4942 GDB now uses a common structure for symbol information internally.
4943 Minimal symbols (derived from linkage symbols in object files), partial
4944 symbols (from a quick scan of debug information), and full symbols
4945 contain a common subset of information, making it easier to write
4946 shared code that handles any of them.
4948 * New command line options
4950 We now accept --silent as an alias for --quiet.
4954 The memory-mapped-malloc library is now licensed under the GNU Library
4955 General Public License.
4957 *** Changes in GDB-4.7:
4959 * Host/native/target split
4961 GDB has had some major internal surgery to untangle the support for
4962 hosts and remote targets. Now, when you configure GDB for a remote
4963 target, it will no longer load in all of the support for debugging
4964 local programs on the host. When fully completed and tested, this will
4965 ensure that arbitrary host/target combinations are possible.
4967 The primary conceptual shift is to separate the non-portable code in
4968 GDB into three categories. Host specific code is required any time GDB
4969 is compiled on that host, regardless of the target. Target specific
4970 code relates to the peculiarities of the target, but can be compiled on
4971 any host. Native specific code is everything else: it can only be
4972 built when the host and target are the same system. Child process
4973 handling and core file support are two common `native' examples.
4975 GDB's use of /proc for controlling Unix child processes is now cleaner.
4976 It has been split out into a single module under the `target_ops' vector,
4977 plus two native-dependent functions for each system that uses /proc.
4979 * New hosts supported
4981 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4982 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4983 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4985 * New targets supported
4987 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4988 68030 and CPU32 m68030-*-*, m68332-*-*
4990 * New native hosts supported
4992 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4993 (386bsd is not well tested yet)
4994 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4996 * New file formats supported
4998 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4999 supports reading of `a.out.adobe' object files, which are an a.out
5000 format extended with minimal information about multiple sections.
5004 `show copying' is the same as the old `info copying'.
5005 `show warranty' is the same as `info warrantee'.
5006 These were renamed for consistency. The old commands continue to work.
5008 `info handle' is a new alias for `info signals'.
5010 You can now define pre-command hooks, which attach arbitrary command
5011 scripts to any command. The commands in the hook will be executed
5012 prior to the user's command. You can also create a hook which will be
5013 executed whenever the program stops. See gdb.texinfo.
5017 We now deal with Cfront style name mangling, and can even extract type
5018 info from mangled symbols. GDB can automatically figure out which
5019 symbol mangling style your C++ compiler uses.
5021 Calling of methods and virtual functions has been improved as well.
5025 The crash that occured when debugging Sun Ansi-C compiled binaries is
5026 fixed. This was due to mishandling of the extra N_SO stabs output
5029 We also finally got Ultrix 4.2 running in house, and fixed core file
5030 support, with help from a dozen people on the net.
5032 John M. Farrell discovered that the reason that single-stepping was so
5033 slow on all of the Mips based platforms (primarily SGI and DEC) was
5034 that we were trying to demangle and lookup a symbol used for internal
5035 purposes on every instruction that was being stepped through. Changing
5036 the name of that symbol so that it couldn't be mistaken for a C++
5037 mangled symbol sped things up a great deal.
5039 Rich Pixley sped up symbol lookups in general by getting much smarter
5040 about when C++ symbol mangling is necessary. This should make symbol
5041 completion (TAB on the command line) much faster. It's not as fast as
5042 we'd like, but it's significantly faster than gdb-4.6.
5046 A new user controllable variable 'call_scratch_address' can
5047 specify the location of a scratch area to be used when GDB
5048 calls a function in the target. This is necessary because the
5049 usual method of putting the scratch area on the stack does not work
5050 in systems that have separate instruction and data spaces.
5052 We integrated changes to support the 29k UDI (Universal Debugger
5053 Interface), but discovered at the last minute that we didn't have all
5054 of the appropriate copyright paperwork. We are working with AMD to
5055 resolve this, and hope to have it available soon.
5059 We have sped up the remote serial line protocol, especially for targets
5060 with lots of registers. It now supports a new `expedited status' ('T')
5061 message which can be used in place of the existing 'S' status message.
5062 This allows the remote stub to send only the registers that GDB
5063 needs to make a quick decision about single-stepping or conditional
5064 breakpoints, eliminating the need to fetch the entire register set for
5065 each instruction being stepped through.
5067 The GDB remote serial protocol now implements a write-through cache for
5068 registers, only re-reading the registers if the target has run.
5070 There is also a new remote serial stub for SPARC processors. You can
5071 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5072 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5073 processor with a serial port.
5077 Configure.in files have become much easier to read and modify. A new
5078 `table driven' format makes it more obvious what configurations are
5079 supported, and what files each one uses.
5083 There is a new opcodes library which will eventually contain all of the
5084 disassembly routines and opcode tables. At present, it only contains
5085 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5086 disassembler (binutils/objdump) to share these routines.
5088 The libiberty library is now copylefted under the GNU Library General
5089 Public License. This allows more liberal use, and was done so libg++
5090 can use it. This makes no difference to GDB, since the Library License
5091 grants all the rights from the General Public License.
5095 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5096 reference to the stabs symbol info used by the debugger. It is (as far
5097 as we know) the only published document on this fascinating topic. We
5098 encourage you to read it, compare it to the stabs information on your
5099 system, and send improvements on the document in general (to
5100 bug-gdb@prep.ai.mit.edu).
5102 And, of course, many bugs have been fixed.
5105 *** Changes in GDB-4.6:
5107 * Better support for C++ function names
5109 GDB now accepts as input the "demangled form" of C++ overloaded function
5110 names and member function names, and can do command completion on such names
5111 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5112 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5113 Make use of command completion, it is your friend.
5115 GDB also now accepts a variety of C++ mangled symbol formats. They are
5116 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5117 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5118 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5119 for the list of formats.
5121 * G++ symbol mangling problem
5123 Recent versions of gcc have a bug in how they emit debugging information for
5124 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5125 directory) can be applied to gcc to fix the problem. Alternatively, if you
5126 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5127 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5128 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5131 * New 'maintenance' command
5133 All of the commands related to hacking GDB internals have been moved out of
5134 the main command set, and now live behind the 'maintenance' command. This
5135 can also be abbreviated as 'mt'. The following changes were made:
5137 dump-me -> maintenance dump-me
5138 info all-breakpoints -> maintenance info breakpoints
5139 printmsyms -> maintenance print msyms
5140 printobjfiles -> maintenance print objfiles
5141 printpsyms -> maintenance print psymbols
5142 printsyms -> maintenance print symbols
5144 The following commands are new:
5146 maintenance demangle Call internal GDB demangler routine to
5147 demangle a C++ link name and prints the result.
5148 maintenance print type Print a type chain for a given symbol
5150 * Change to .gdbinit file processing
5152 We now read the $HOME/.gdbinit file before processing the argv arguments
5153 (e.g. reading symbol files or core files). This allows global parameters to
5154 be set, which will apply during the symbol reading. The ./.gdbinit is still
5155 read after argv processing.
5157 * New hosts supported
5159 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5161 GNU/Linux support i386-unknown-linux or linux
5163 We are also including code to support the HP/PA running BSD and HPUX. This
5164 is almost guaranteed not to work, as we didn't have time to test or build it
5165 for this release. We are including it so that the more adventurous (or
5166 masochistic) of you can play with it. We also had major problems with the
5167 fact that the compiler that we got from HP doesn't support the -g option.
5170 * New targets supported
5172 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5174 * More smarts about finding #include files
5176 GDB now remembers the compilation directory for all include files, and for
5177 all files from which C is generated (like yacc and lex sources). This
5178 greatly improves GDB's ability to find yacc/lex sources, and include files,
5179 especially if you are debugging your program from a directory different from
5180 the one that contains your sources.
5182 We also fixed a bug which caused difficulty with listing and setting
5183 breakpoints in include files which contain C code. (In the past, you had to
5184 try twice in order to list an include file that you hadn't looked at before.)
5186 * Interesting infernals change
5188 GDB now deals with arbitrary numbers of sections, where the symbols for each
5189 section must be relocated relative to that section's landing place in the
5190 target's address space. This work was needed to support ELF with embedded
5191 stabs used by Solaris-2.0.
5193 * Bug fixes (of course!)
5195 There have been loads of fixes for the following things:
5196 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5197 i960, stabs, DOS(GO32), procfs, etc...
5199 See the ChangeLog for details.
5201 *** Changes in GDB-4.5:
5203 * New machines supported (host and target)
5205 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5207 SGI Irix-4.x mips-sgi-irix4 or iris4
5209 * New malloc package
5211 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5212 Mmalloc is capable of handling mutiple heaps of memory. It is also
5213 capable of saving a heap to a file, and then mapping it back in later.
5214 This can be used to greatly speedup the startup of GDB by using a
5215 pre-parsed symbol table which lives in a mmalloc managed heap. For
5216 more details, please read mmalloc/mmalloc.texi.
5220 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5221 'help info proc' for details.
5223 * MIPS ecoff symbol table format
5225 The code that reads MIPS symbol table format is now supported on all hosts.
5226 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5229 * File name changes for MS-DOS
5231 Many files in the config directories have been renamed to make it easier to
5232 support GDB on MS-DOSe systems (which have very restrictive file name
5233 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5234 environment) is close to working but has some remaining problems. Note
5235 that debugging of DOS programs is not supported, due to limitations
5236 in the ``operating system'', but it can be used to host cross-debugging.
5238 * Cross byte order fixes
5240 Many fixes have been made to support cross debugging of Sparc and MIPS
5241 targets from hosts whose byte order differs.
5243 * New -mapped and -readnow options
5245 If memory-mapped files are available on your system through the 'mmap'
5246 system call, you can use the -mapped option on the `file' or
5247 `symbol-file' commands to cause GDB to write the symbols from your
5248 program into a reusable file. If the program you are debugging is
5249 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5250 Future GDB debugging sessions will notice the presence of this file,
5251 and will quickly map in symbol information from it, rather than reading
5252 the symbol table from the executable program. Using the '-mapped'
5253 option in a GDB `file' or `symbol-file' command has the same effect as
5254 starting GDB with the '-mapped' command-line option.
5256 You can cause GDB to read the entire symbol table immediately by using
5257 the '-readnow' option with any of the commands that load symbol table
5258 information (or on the GDB command line). This makes the command
5259 slower, but makes future operations faster.
5261 The -mapped and -readnow options are typically combined in order to
5262 build a `fred.syms' file that contains complete symbol information.
5263 A simple GDB invocation to do nothing but build a `.syms' file for future
5266 gdb -batch -nx -mapped -readnow programname
5268 The `.syms' file is specific to the host machine on which GDB is run.
5269 It holds an exact image of GDB's internal symbol table. It cannot be
5270 shared across multiple host platforms.
5272 * longjmp() handling
5274 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5275 siglongjmp() without losing control. This feature has not yet been ported to
5276 all systems. It currently works on many 386 platforms, all MIPS-based
5277 platforms (SGI, DECstation, etc), and Sun3/4.
5281 Preliminary work has been put in to support the new Solaris OS from Sun. At
5282 this time, it can control and debug processes, but it is not capable of
5287 As always, many many bug fixes. The major areas were with g++, and mipsread.
5288 People using the MIPS-based platforms should experience fewer mysterious
5289 crashes and trashed symbol tables.
5291 *** Changes in GDB-4.4:
5293 * New machines supported (host and target)
5295 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5297 BSD Reno on Vax vax-dec-bsd
5298 Ultrix on Vax vax-dec-ultrix
5300 * New machines supported (target)
5302 AMD 29000 embedded, using EBMON a29k-none-none
5306 GDB continues to improve its handling of C++. `References' work better.
5307 The demangler has also been improved, and now deals with symbols mangled as
5308 per the Annotated C++ Reference Guide.
5310 GDB also now handles `stabs' symbol information embedded in MIPS
5311 `ecoff' symbol tables. Since the ecoff format was not easily
5312 extensible to handle new languages such as C++, this appeared to be a
5313 good way to put C++ debugging info into MIPS binaries. This option
5314 will be supported in the GNU C compiler, version 2, when it is
5317 * New features for SVR4
5319 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5320 shared libraries. Debugging dynamically linked programs should present
5321 only minor differences from debugging statically linked programs.
5323 The `info proc' command will print out information about any process
5324 on an SVR4 system (including the one you are debugging). At the moment,
5325 it prints the address mappings of the process.
5327 If you bring up GDB on another SVR4 system, please send mail to
5328 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5330 * Better dynamic linking support in SunOS
5332 Reading symbols from shared libraries which contain debugging symbols
5333 now works properly. However, there remain issues such as automatic
5334 skipping of `transfer vector' code during function calls, which
5335 make it harder to debug code in a shared library, than to debug the
5336 same code linked statically.
5340 GDB is now using the latest `getopt' routines from the FSF. This
5341 version accepts the -- prefix for options with long names. GDB will
5342 continue to accept the old forms (-option and +option) as well.
5343 Various single letter abbreviations for options have been explicity
5344 added to the option table so that they won't get overshadowed in the
5345 future by other options that begin with the same letter.
5349 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5350 Many assorted bugs have been handled. Many more remain to be handled.
5351 See the various ChangeLog files (primarily in gdb and bfd) for details.
5354 *** Changes in GDB-4.3:
5356 * New machines supported (host and target)
5358 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5359 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5360 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5362 * Almost SCO Unix support
5364 We had hoped to support:
5365 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5366 (except for core file support), but we discovered very late in the release
5367 that it has problems with process groups that render gdb unusable. Sorry
5368 about that. I encourage people to fix it and post the fixes.
5370 * Preliminary ELF and DWARF support
5372 GDB can read ELF object files on System V Release 4, and can handle
5373 debugging records for C, in DWARF format, in ELF files. This support
5374 is preliminary. If you bring up GDB on another SVR4 system, please
5375 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5380 GDB now uses the latest `readline' library. One user-visible change
5381 is that two tabs will list possible command completions, which previously
5382 required typing M-? (meta-question mark, or ESC ?).
5386 The `stepi' bug that many of you noticed has been squashed.
5387 Many bugs in C++ have been handled. Many more remain to be handled.
5388 See the various ChangeLog files (primarily in gdb and bfd) for details.
5390 * State of the MIPS world (in case you wondered):
5392 GDB can understand the symbol tables emitted by the compilers
5393 supplied by most vendors of MIPS-based machines, including DEC. These
5394 symbol tables are in a format that essentially nobody else uses.
5396 Some versions of gcc come with an assembler post-processor called
5397 mips-tfile. This program is required if you want to do source-level
5398 debugging of gcc-compiled programs. I believe FSF does not ship
5399 mips-tfile with gcc version 1, but it will eventually come with gcc
5402 Debugging of g++ output remains a problem. g++ version 1.xx does not
5403 really support it at all. (If you're lucky, you should be able to get
5404 line numbers and stack traces to work, but no parameters or local
5405 variables.) With some work it should be possible to improve the
5408 When gcc version 2 is released, you will have somewhat better luck.
5409 However, even then you will get confusing results for inheritance and
5412 We will eventually provide full debugging of g++ output on
5413 DECstations. This will probably involve some kind of stabs-in-ecoff
5414 encapulation, but the details have not been worked out yet.
5417 *** Changes in GDB-4.2:
5419 * Improved configuration
5421 Only one copy of `configure' exists now, and it is not self-modifying.
5422 Porting BFD is simpler.
5426 The `step' and `next' commands now only stop at the first instruction
5427 of a source line. This prevents the multiple stops that used to occur
5428 in switch statements, for-loops, etc. `Step' continues to stop if a
5429 function that has debugging information is called within the line.
5433 Lots of small bugs fixed. More remain.
5435 * New host supported (not target)
5437 Intel 386 PC clone running Mach i386-none-mach
5440 *** Changes in GDB-4.1:
5442 * Multiple source language support
5444 GDB now has internal scaffolding to handle several source languages.
5445 It determines the type of each source file from its filename extension,
5446 and will switch expression parsing and number formatting to match the
5447 language of the function in the currently selected stack frame.
5448 You can also specifically set the language to be used, with
5449 `set language c' or `set language modula-2'.
5453 GDB now has preliminary support for the GNU Modula-2 compiler,
5454 currently under development at the State University of New York at
5455 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5456 continue through the fall of 1991 and into 1992.
5458 Other Modula-2 compilers are currently not supported, and attempting to
5459 debug programs compiled with them will likely result in an error as the
5460 symbol table is read. Feel free to work on it, though!
5462 There are hooks in GDB for strict type checking and range checking,
5463 in the `Modula-2 philosophy', but they do not currently work.
5467 GDB can now write to executable and core files (e.g. patch
5468 a variable's value). You must turn this switch on, specify
5469 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5470 by assigning a new value to a variable. Modifications take
5473 * Automatic SunOS shared library reading
5475 When you run your program, GDB automatically determines where its
5476 shared libraries (if any) have been loaded, and reads their symbols.
5477 The `share' command is no longer needed. This also works when
5478 examining core files.
5482 You can specify the number of lines that the `list' command shows.
5485 * New machines supported (host and target)
5487 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5488 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5489 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5491 * New hosts supported (not targets)
5493 IBM RT/PC: romp-ibm-aix or rtpc
5495 * New targets supported (not hosts)
5497 AMD 29000 embedded with COFF a29k-none-coff
5498 AMD 29000 embedded with a.out a29k-none-aout
5499 Ultracomputer remote kernel debug a29k-nyu-kern
5501 * New remote interfaces
5507 *** Changes in GDB-4.0:
5511 Wide output is wrapped at good places to make the output more readable.
5513 Gdb now supports cross-debugging from a host machine of one type to a
5514 target machine of another type. Communication with the target system
5515 is over serial lines. The ``target'' command handles connecting to the
5516 remote system; the ``load'' command will download a program into the
5517 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5518 also supports debugging of realtime processes running under VxWorks,
5519 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5520 stub on the target system.
5522 New CPUs supported include the AMD 29000 and Intel 960.
5524 GDB now reads object files and symbol tables via a ``binary file''
5525 library, which allows a single copy of GDB to debug programs of multiple
5526 object file types such as a.out and coff.
5528 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5529 refcard.dvi and refcard.ps are available to format it).
5532 * Control-Variable user interface simplified
5534 All variables that control the operation of the debugger can be set
5535 by the ``set'' command, and displayed by the ``show'' command.
5537 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5538 ``Show prompt'' produces the response:
5539 Gdb's prompt is new-gdb=>.
5541 What follows are the NEW set commands. The command ``help set'' will
5542 print a complete list of old and new set commands. ``help set FOO''
5543 will give a longer description of the variable FOO. ``show'' will show
5544 all of the variable descriptions and their current settings.
5546 confirm on/off: Enables warning questions for operations that are
5547 hard to recover from, e.g. rerunning the program while
5548 it is already running. Default is ON.
5550 editing on/off: Enables EMACS style command line editing
5551 of input. Previous lines can be recalled with
5552 control-P, the current line can be edited with control-B,
5553 you can search for commands with control-R, etc.
5556 history filename NAME: NAME is where the gdb command history
5557 will be stored. The default is .gdb_history,
5558 or the value of the environment variable
5561 history size N: The size, in commands, of the command history. The
5562 default is 256, or the value of the environment variable
5565 history save on/off: If this value is set to ON, the history file will
5566 be saved after exiting gdb. If set to OFF, the
5567 file will not be saved. The default is OFF.
5569 history expansion on/off: If this value is set to ON, then csh-like
5570 history expansion will be performed on
5571 command line input. The default is OFF.
5573 radix N: Sets the default radix for input and output. It can be set
5574 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5575 in the current radix, so "set radix 10" is always a no-op.
5577 height N: This integer value is the number of lines on a page. Default
5578 is 24, the current `stty rows'' setting, or the ``li#''
5579 setting from the termcap entry matching the environment
5582 width N: This integer value is the number of characters on a line.
5583 Default is 80, the current `stty cols'' setting, or the ``co#''
5584 setting from the termcap entry matching the environment
5587 Note: ``set screensize'' is obsolete. Use ``set height'' and
5588 ``set width'' instead.
5590 print address on/off: Print memory addresses in various command displays,
5591 such as stack traces and structure values. Gdb looks
5592 more ``symbolic'' if you turn this off; it looks more
5593 ``machine level'' with it on. Default is ON.
5595 print array on/off: Prettyprint arrays. New convenient format! Default
5598 print demangle on/off: Print C++ symbols in "source" form if on,
5601 print asm-demangle on/off: Same, for assembler level printouts
5604 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5607 * Support for Epoch Environment.
5609 The epoch environment is a version of Emacs v18 with windowing. One
5610 new command, ``inspect'', is identical to ``print'', except that if you
5611 are running in the epoch environment, the value is printed in its own
5615 * Support for Shared Libraries
5617 GDB can now debug programs and core files that use SunOS shared libraries.
5618 Symbols from a shared library cannot be referenced
5619 before the shared library has been linked with the program (this
5620 happens after you type ``run'' and before the function main() is entered).
5621 At any time after this linking (including when examining core files
5622 from dynamically linked programs), gdb reads the symbols from each
5623 shared library when you type the ``sharedlibrary'' command.
5624 It can be abbreviated ``share''.
5626 sharedlibrary REGEXP: Load shared object library symbols for files
5627 matching a unix regular expression. No argument
5628 indicates to load symbols for all shared libraries.
5630 info sharedlibrary: Status of loaded shared libraries.
5635 A watchpoint stops execution of a program whenever the value of an
5636 expression changes. Checking for this slows down execution
5637 tremendously whenever you are in the scope of the expression, but is
5638 quite useful for catching tough ``bit-spreader'' or pointer misuse
5639 problems. Some machines such as the 386 have hardware for doing this
5640 more quickly, and future versions of gdb will use this hardware.
5642 watch EXP: Set a watchpoint (breakpoint) for an expression.
5644 info watchpoints: Information about your watchpoints.
5646 delete N: Deletes watchpoint number N (same as breakpoints).
5647 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5648 enable N: Re-enables watchpoint number N (same as breakpoints).
5651 * C++ multiple inheritance
5653 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5656 * C++ exception handling
5658 Gdb now supports limited C++ exception handling. Besides the existing
5659 ability to breakpoint on an exception handler, gdb can breakpoint on
5660 the raising of an exception (before the stack is peeled back to the
5663 catch FOO: If there is a FOO exception handler in the dynamic scope,
5664 set a breakpoint to catch exceptions which may be raised there.
5665 Multiple exceptions (``catch foo bar baz'') may be caught.
5667 info catch: Lists all exceptions which may be caught in the
5668 current stack frame.
5671 * Minor command changes
5673 The command ``call func (arg, arg, ...)'' now acts like the print
5674 command, except it does not print or save a value if the function's result
5675 is void. This is similar to dbx usage.
5677 The ``up'' and ``down'' commands now always print the frame they end up
5678 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5679 frames without printing.
5681 * New directory command
5683 'dir' now adds directories to the FRONT of the source search path.
5684 The path starts off empty. Source files that contain debug information
5685 about the directory in which they were compiled can be found even
5686 with an empty path; Sun CC and GCC include this information. If GDB can't
5687 find your source file in the current directory, type "dir .".
5689 * Configuring GDB for compilation
5691 For normal use, type ``./configure host''. See README or gdb.texinfo
5694 GDB now handles cross debugging. If you are remotely debugging between
5695 two different machines, type ``./configure host -target=targ''.
5696 Host is the machine where GDB will run; targ is the machine
5697 where the program that you are debugging will run.
5699 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
5701 * Support for Intel(R) AVX-512 registers on GNU/Linux.
5703 Support displaying and modifying Intel(R) AVX-512 registers $zmm0 - $zmm31 and
5704 $k0 - $k7 on GNU/Linux.