1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.7
6 * The 'record instruction-history' command now starts counting instructions
7 at one. This also affects the instruction ranges reported by the
8 'record function-call-history' command when given the /i modifier.
10 *** Changes in GDB 7.7
12 * Improved support for process record-replay and reverse debugging on
13 arm*-linux* targets. Support for thumb32 and syscall instruction
14 recording has been added.
16 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
18 * GDB now supports Fission DWP file format version 2.
19 http://gcc.gnu.org/wiki/DebugFission
21 * New convenience function "$_isvoid", to check whether an expression
22 is void. A void expression is an expression where the type of the
23 result is "void". For example, some convenience variables may be
24 "void" when evaluated (e.g., "$_exitcode" before the execution of
25 the program being debugged; or an undefined convenience variable).
26 Another example, when calling a function whose return type is
29 * The "maintenance print objfiles" command now takes an optional regexp.
31 * The "catch syscall" command now works on arm*-linux* targets.
33 * GDB now consistently shows "<not saved>" when printing values of
34 registers the debug info indicates have not been saved in the frame
35 and there's nowhere to retrieve them from
36 (callee-saved/call-clobbered registers):
41 (gdb) info registers rax
44 Before, the former would print "<optimized out>", and the latter
45 "*value not available*".
47 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
52 ** Frame filters and frame decorators have been added.
53 ** Temporary breakpoints are now supported.
54 ** Line tables representation has been added.
55 ** New attribute 'parent_type' for gdb.Field objects.
56 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
57 ** New attribute 'name' for gdb.Type objects.
61 Nios II ELF nios2*-*-elf
62 Nios II GNU/Linux nios2*-*-linux
63 Texas Instruments MSP430 msp430*-*-elf
65 * Removed native configurations
67 Support for these a.out NetBSD and OpenBSD obsolete configurations has
68 been removed. ELF variants of these configurations are kept supported.
70 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
71 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
72 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
73 i[34567]86-*-openbsd3.[0-3]
74 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
75 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
76 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
80 Like "catch throw", but catches a re-thrown exception.
82 Renamed from old "maint check-symtabs".
84 Perform consistency checks on symtabs.
86 Expand symtabs matching an optional regexp.
89 Display the details of GDB configure-time options.
91 maint set|show per-command
92 maint set|show per-command space
93 maint set|show per-command time
94 maint set|show per-command symtab
95 Enable display of per-command gdb resource usage.
97 remove-symbol-file FILENAME
98 remove-symbol-file -a ADDRESS
99 Remove a symbol file added via add-symbol-file. The file to remove
100 can be identified by its filename or by an address that lies within
101 the boundaries of this symbol file in memory.
104 info exceptions REGEXP
105 Display the list of Ada exceptions defined in the program being
106 debugged. If provided, only the exceptions whose names match REGEXP
111 set debug symfile off|on
113 Control display of debugging info regarding reading symbol files and
114 symbol tables within those files
116 set print raw frame-arguments
117 show print raw frame-arguments
118 Set/show whether to print frame arguments in raw mode,
119 disregarding any defined pretty-printers.
121 set remote trace-status-packet
122 show remote trace-status-packet
123 Set/show the use of remote protocol qTStatus packet.
127 Control display of debugging messages related to Nios II targets.
131 Control whether target-assisted range stepping is enabled.
133 set startup-with-shell
134 show startup-with-shell
135 Specifies whether Unix child processes are started via a shell or
140 Use the target memory cache for accesses to the code segment. This
141 improves performance of remote debugging (particularly disassembly).
143 * You can now use a literal value 'unlimited' for options that
144 interpret 0 or -1 as meaning "unlimited". E.g., "set
145 trace-buffer-size unlimited" is now an alias for "set
146 trace-buffer-size -1" and "set height unlimited" is now an alias for
149 * The "set debug symtab-create" debugging option of GDB has been changed to
150 accept a verbosity level. 0 means "off", 1 provides basic debugging
151 output, and values of 2 or greater provides more verbose output.
153 * New command-line options
155 Display the details of GDB configure-time options.
157 * The command 'tsave' can now support new option '-ctf' to save trace
158 buffer in Common Trace Format.
160 * Newly installed $prefix/bin/gcore acts as a shell interface for the
163 * GDB now implements the the C++ 'typeid' operator.
165 * The new convenience variable $_exception holds the exception being
166 thrown or caught at an exception-related catchpoint.
168 * The exception-related catchpoints, like "catch throw", now accept a
169 regular expression which can be used to filter exceptions by type.
171 * The new convenience variable $_exitsignal is automatically set to
172 the terminating signal number when the program being debugged dies
173 due to an uncaught signal.
177 ** All MI commands now accept an optional "--language" option.
178 Support for this feature can be verified by using the "-list-features"
179 command, which should contain "language-option".
181 ** The new command -info-gdb-mi-command allows the user to determine
182 whether a GDB/MI command is supported or not.
184 ** The "^error" result record returned when trying to execute an undefined
185 GDB/MI command now provides a variable named "code" whose content is the
186 "undefined-command" error code. Support for this feature can be verified
187 by using the "-list-features" command, which should contain
188 "undefined-command-error-code".
190 ** The -trace-save MI command can optionally save trace buffer in Common
193 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
195 ** The command -data-list-register-values now accepts an optional
196 "--skip-unavailable" option. When used, only the available registers
199 ** The new command -trace-frame-collected dumps collected variables,
200 computed expressions, tvars, memory and registers in a traceframe.
202 ** The commands -stack-list-locals, -stack-list-arguments and
203 -stack-list-variables now accept an option "--skip-unavailable".
204 When used, only the available locals or arguments are displayed.
206 ** The -exec-run command now accepts an optional "--start" option.
207 When used, the command follows the same semantics as the "start"
208 command, stopping the program's execution at the start of its
209 main subprogram. Support for this feature can be verified using
210 the "-list-features" command, which should contain
211 "exec-run-start-option".
213 ** The new commands -catch-assert and -catch-exceptions insert
214 catchpoints stopping the program when Ada exceptions are raised.
216 ** The new command -info-ada-exceptions provides the equivalent of
217 the new "info exceptions" command.
219 * New system-wide configuration scripts
220 A GDB installation now provides scripts suitable for use as system-wide
221 configuration scripts for the following systems:
225 * GDB now supports target-assigned range stepping with remote targets.
226 This improves the performance of stepping source lines by reducing
227 the number of control packets from/to GDB. See "New remote packets"
230 * GDB now understands the element 'tvar' in the XML traceframe info.
231 It has the id of the collected trace state variables.
233 * On S/390 targets that provide the transactional-execution feature,
234 the program interruption transaction diagnostic block (TDB) is now
235 represented as a number of additional "registers" in GDB.
241 The vCont packet supports a new 'r' action, that tells the remote
242 stub to step through an address range itself, without GDB
243 involvemement at each single-step.
245 qXfer:libraries-svr4:read's annex
246 The previously unused annex of the qXfer:libraries-svr4:read packet
247 is now used to support passing an argument list. The remote stub
248 reports support for this argument list to GDB's qSupported query.
249 The defined arguments are "start" and "prev", used to reduce work
250 necessary for library list updating, resulting in significant
253 * New features in the GDB remote stub, GDBserver
255 ** GDBserver now supports target-assisted range stepping. Currently
256 enabled on x86/x86_64 GNU/Linux targets.
258 ** GDBserver now adds element 'tvar' in the XML in the reply to
259 'qXfer:traceframe-info:read'. It has the id of the collected
260 trace state variables.
262 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
265 * New 'z' formatter for printing and examining memory, this displays the
266 value as hexadecimal zero padded on the left to the size of the type.
268 * GDB can now use Windows x64 unwinding data.
270 * The "set remotebaud" command has been replaced by "set serial baud".
271 Similarly, "show remotebaud" has been replaced by "show serial baud".
272 The "set remotebaud" and "show remotebaud" commands are still available
273 to provide backward compatibility with older versions of GDB.
275 *** Changes in GDB 7.6
277 * Target record has been renamed to record-full.
278 Record/replay is now enabled with the "record full" command.
279 This also affects settings that are associated with full record/replay
280 that have been moved from "set/show record" to "set/show record full":
282 set|show record full insn-number-max
283 set|show record full stop-at-limit
284 set|show record full memory-query
286 * A new record target "record-btrace" has been added. The new target
287 uses hardware support to record the control-flow of a process. It
288 does not support replaying the execution, but it implements the
289 below new commands for investigating the recorded execution log.
290 This new recording method can be enabled using:
294 The "record-btrace" target is only available on Intel Atom processors
295 and requires a Linux kernel 2.6.32 or later.
297 * Two new commands have been added for record/replay to give information
298 about the recorded execution without having to replay the execution.
299 The commands are only supported by "record btrace".
301 record instruction-history prints the execution history at
302 instruction granularity
304 record function-call-history prints the execution history at
307 * New native configurations
309 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
310 FreeBSD/powerpc powerpc*-*-freebsd
311 x86_64/Cygwin x86_64-*-cygwin*
312 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
316 ARM AArch64 aarch64*-*-elf
317 ARM AArch64 GNU/Linux aarch64*-*-linux
318 Lynx 178 PowerPC powerpc-*-lynx*178
319 x86_64/Cygwin x86_64-*-cygwin*
320 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
322 * If the configured location of system.gdbinit file (as given by the
323 --with-system-gdbinit option at configure time) is in the
324 data-directory (as specified by --with-gdb-datadir at configure
325 time) or in one of its subdirectories, then GDB will look for the
326 system-wide init file in the directory specified by the
327 --data-directory command-line option.
329 * New command line options:
331 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
332 other initialization files, unlike -nx which disables all of them.
334 * Removed command line options
336 -epoch This was used by the gdb mode in Epoch, an ancient fork of
339 * The 'ptype' and 'whatis' commands now accept an argument to control
342 * 'info proc' now works on some core files.
346 ** Vectors can be created with gdb.Type.vector.
348 ** Python's atexit.register now works in GDB.
350 ** Types can be pretty-printed via a Python API.
352 ** Python 3 is now supported (in addition to Python 2.4 or later)
354 ** New class gdb.Architecture exposes GDB's internal representation
355 of architecture in the Python API.
357 ** New method Frame.architecture returns the gdb.Architecture object
358 corresponding to the frame's architecture.
360 * New Python-based convenience functions:
362 ** $_memeq(buf1, buf2, length)
363 ** $_streq(str1, str2)
365 ** $_regex(str, regex)
367 * The 'cd' command now defaults to using '~' (the home directory) if not
370 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
371 default for GCC since November 2000.
373 * The command 'forward-search' can now be abbreviated as 'fo'.
375 * The command 'info tracepoints' can now display 'installed on target'
376 or 'not installed on target' for each non-pending location of tracepoint.
378 * New configure options
380 --enable-libmcheck/--disable-libmcheck
381 By default, development versions are built with -lmcheck on hosts
382 that support it, in order to help track memory corruption issues.
383 Release versions, on the other hand, are built without -lmcheck
384 by default. The --enable-libmcheck/--disable-libmcheck configure
385 options allow the user to override that default.
386 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
387 This configure option allows the user to build GDB with
388 libbabeltrace using which GDB can read Common Trace Format data.
390 * New commands (for set/show, see "New options" below)
393 Catch signals. This is similar to "handle", but allows commands and
394 conditions to be attached.
397 List the BFDs known to GDB.
399 python-interactive [command]
401 Start a Python interactive prompt, or evaluate the optional command
402 and print the result of expressions.
405 "py" is a new alias for "python".
407 enable type-printer [name]...
408 disable type-printer [name]...
409 Enable or disable type printers.
413 ** For the Renesas Super-H architecture, the "regs" command has been removed
414 (has been deprecated in GDB 7.5), and "info all-registers" should be used
419 set print type methods (on|off)
420 show print type methods
421 Control whether method declarations are displayed by "ptype".
422 The default is to show them.
424 set print type typedefs (on|off)
425 show print type typedefs
426 Control whether typedef definitions are displayed by "ptype".
427 The default is to show them.
429 set filename-display basename|relative|absolute
430 show filename-display
431 Control the way in which filenames is displayed.
432 The default is "relative", which preserves previous behavior.
434 set trace-buffer-size
435 show trace-buffer-size
436 Request target to change the size of trace buffer.
438 set remote trace-buffer-size-packet auto|on|off
439 show remote trace-buffer-size-packet
440 Control the use of the remote protocol `QTBuffer:size' packet.
444 Control display of debugging messages related to ARM AArch64.
447 set debug coff-pe-read
448 show debug coff-pe-read
449 Control display of debugging messages related to reading of COFF/PE
454 Control display of debugging messages related to Mach-O symbols
457 set debug notification
458 show debug notification
459 Control display of debugging info for async remote notification.
463 ** Command parameter changes are now notified using new async record
464 "=cmd-param-changed".
465 ** Trace frame changes caused by command "tfind" are now notified using
466 new async record "=traceframe-changed".
467 ** The creation, deletion and modification of trace state variables
468 are now notified using new async records "=tsv-created",
469 "=tsv-deleted" and "=tsv-modified".
470 ** The start and stop of process record are now notified using new
471 async record "=record-started" and "=record-stopped".
472 ** Memory changes are now notified using new async record
474 ** The data-disassemble command response will include a "fullname" field
475 containing the absolute file name when source has been requested.
476 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
477 command, to allow pattern filling of memory areas.
478 ** New commands "-catch-load"/"-catch-unload" added for intercepting
479 library load/unload events.
480 ** The response to breakpoint commands and breakpoint async records
481 includes an "installed" field containing a boolean state about each
482 non-pending tracepoint location is whether installed on target or not.
483 ** Output of the "-trace-status" command includes a "trace-file" field
484 containing the name of the trace file being examined. This field is
485 optional, and only present when examining a trace file.
486 ** The "fullname" field is now always present along with the "file" field,
487 even if the file cannot be found by GDB.
489 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
490 You must have the LZMA library available when configuring GDB for this
491 feature to be enabled. For more information, see:
492 http://fedoraproject.org/wiki/Features/MiniDebugInfo
497 Set the size of trace buffer. The remote stub reports support for this
498 packet to gdb's qSupported query.
501 Enable Branch Trace Store (BTS)-based branch tracing for the current
502 thread. The remote stub reports support for this packet to gdb's
506 Disable branch tracing for the current thread. The remote stub reports
507 support for this packet to gdb's qSupported query.
510 Read the traced branches for the current thread. The remote stub
511 reports support for this packet to gdb's qSupported query.
513 *** Changes in GDB 7.5
515 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
516 for more x32 ABI info.
518 * GDB now supports access to MIPS DSP registers on Linux targets.
520 * GDB now supports debugging microMIPS binaries.
522 * The "info os" command on GNU/Linux can now display information on
523 several new classes of objects managed by the operating system:
524 "info os procgroups" lists process groups
525 "info os files" lists file descriptors
526 "info os sockets" lists internet-domain sockets
527 "info os shm" lists shared-memory regions
528 "info os semaphores" lists semaphores
529 "info os msg" lists message queues
530 "info os modules" lists loaded kernel modules
532 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
533 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
534 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
535 options and inspect the probe arguments using the new $_probe_arg family
536 of convenience variables. You can obtain more information about SystemTap
537 in <http://sourceware.org/systemtap/>.
539 * GDB now supports reversible debugging on ARM, it allows you to
540 debug basic ARM and THUMB instructions, and provides
541 record/replay support.
543 * The option "symbol-reloading" has been deleted as it is no longer used.
547 ** GDB commands implemented in Python can now be put in command class
550 ** The "maint set python print-stack on|off" is now deleted.
552 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
553 apply "flag enum"-style pretty-printing to any enum.
555 ** gdb.lookup_symbol can now work when there is no current frame.
557 ** gdb.Symbol now has a 'line' attribute, holding the line number in
558 the source at which the symbol was defined.
560 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
561 method 'value'. The former indicates whether the symbol needs a
562 frame in order to compute its value, and the latter computes the
565 ** A new method 'referenced_value' on gdb.Value objects which can
566 dereference pointer as well as C++ reference values.
568 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
569 which return the global and static blocks (as gdb.Block objects),
570 of the underlying symbol table, respectively.
572 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
573 object associated with a PC value.
575 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
576 of the address range occupied by code for the current source line.
578 * Go language support.
579 GDB now supports debugging programs written in the Go programming
582 * GDBserver now supports stdio connections.
583 E.g. (gdb) target remote | ssh myhost gdbserver - hello
585 * The binary "gdbtui" can no longer be built or installed.
586 Use "gdb -tui" instead.
588 * GDB will now print "flag" enums specially. A flag enum is one where
589 all the enumerator values have no bits in common when pairwise
590 "and"ed. When printing a value whose type is a flag enum, GDB will
591 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
592 (gdb) print (enum E) 3
595 * The filename part of a linespec will now match trailing components
596 of a source file name. For example, "break gcc/expr.c:1000" will
597 now set a breakpoint in build/gcc/expr.c, but not
600 * The "info proc" and "generate-core-file" commands will now also
601 work on remote targets connected to GDBserver on Linux.
603 * The command "info catch" has been removed. It has been disabled
606 * The "catch exception" and "catch assert" commands now accept
607 a condition at the end of the command, much like the "break"
608 command does. For instance:
610 (gdb) catch exception Constraint_Error if Barrier = True
612 Previously, it was possible to add a condition to such catchpoints,
613 but it had to be done as a second step, after the catchpoint had been
614 created, using the "condition" command.
616 * The "info static-tracepoint-marker" command will now also work on
617 native Linux targets with in-process agent.
619 * GDB can now set breakpoints on inlined functions.
621 * The .gdb_index section has been updated to include symbols for
622 inlined functions. GDB will ignore older .gdb_index sections by
623 default, which could cause symbol files to be loaded more slowly
624 until their .gdb_index sections can be recreated. The new command
625 "set use-deprecated-index-sections on" will cause GDB to use any older
626 .gdb_index sections it finds. This will restore performance, but the
627 ability to set breakpoints on inlined functions will be lost in symbol
628 files with older .gdb_index sections.
630 The .gdb_index section has also been updated to record more information
631 about each symbol. This speeds up the "info variables", "info functions"
632 and "info types" commands when used with programs having the .gdb_index
633 section, as well as speeding up debugging with shared libraries using
634 the .gdb_index section.
636 * Ada support for GDB/MI Variable Objects has been added.
638 * GDB can now support 'breakpoint always-inserted mode' in 'record'
643 ** New command -info-os is the MI equivalent of "info os".
645 ** Output logs ("set logging" and related) now include MI output.
649 ** "set use-deprecated-index-sections on|off"
650 "show use-deprecated-index-sections on|off"
651 Controls the use of deprecated .gdb_index sections.
653 ** "catch load" and "catch unload" can be used to stop when a shared
654 library is loaded or unloaded, respectively.
656 ** "enable count" can be used to auto-disable a breakpoint after
659 ** "info vtbl" can be used to show the virtual method tables for
660 C++ and Java objects.
662 ** "explore" and its sub commands "explore value" and "explore type"
663 can be used to recursively explore values and types of
664 expressions. These commands are available only if GDB is
665 configured with '--with-python'.
667 ** "info auto-load" shows status of all kinds of auto-loaded files,
668 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
669 sequences of commands files, "info auto-load python-scripts"
670 shows status of auto-loading Python script files,
671 "info auto-load local-gdbinit" shows status of loading init file
672 (.gdbinit) from current directory and "info auto-load libthread-db" shows
673 status of inferior specific thread debugging shared library loading.
675 ** "info auto-load-scripts", "set auto-load-scripts on|off"
676 and "show auto-load-scripts" commands have been deprecated, use their
677 "info auto-load python-scripts", "set auto-load python-scripts on|off"
678 and "show auto-load python-scripts" counterparts instead.
680 ** "dprintf location,format,args..." creates a dynamic printf, which
681 is basically a breakpoint that does a printf and immediately
682 resumes your program's execution, so it is like a printf that you
683 can insert dynamically at runtime instead of at compiletime.
685 ** "set print symbol"
687 Controls whether GDB attempts to display the symbol, if any,
688 corresponding to addresses it prints. This defaults to "on", but
689 you can set it to "off" to restore GDB's previous behavior.
691 * Deprecated commands
693 ** For the Renesas Super-H architecture, the "regs" command has been
694 deprecated, and "info all-registers" should be used instead.
698 Renesas RL78 rl78-*-elf
699 HP OpenVMS ia64 ia64-hp-openvms*
701 * GDBserver supports evaluation of breakpoint conditions. When
702 support is advertised by GDBserver, GDB may be told to send the
703 breakpoint conditions in bytecode form to GDBserver. GDBserver
704 will only report the breakpoint trigger to GDB when its condition
710 show mips compression
711 Select the compressed ISA encoding used in functions that have no symbol
712 information available. The encoding can be set to either of:
715 and is updated automatically from ELF file flags if available.
717 set breakpoint condition-evaluation
718 show breakpoint condition-evaluation
719 Control whether breakpoint conditions are evaluated by GDB ("host") or by
720 GDBserver ("target"). Default option "auto" chooses the most efficient
722 This option can improve debugger efficiency depending on the speed of the
726 Disable auto-loading globally.
729 Show auto-loading setting of all kinds of auto-loaded files.
731 set auto-load gdb-scripts on|off
732 show auto-load gdb-scripts
733 Control auto-loading of GDB canned sequences of commands files.
735 set auto-load python-scripts on|off
736 show auto-load python-scripts
737 Control auto-loading of Python script files.
739 set auto-load local-gdbinit on|off
740 show auto-load local-gdbinit
741 Control loading of init file (.gdbinit) from current directory.
743 set auto-load libthread-db on|off
744 show auto-load libthread-db
745 Control auto-loading of inferior specific thread debugging shared library.
747 set auto-load scripts-directory <dir1>[:<dir2>...]
748 show auto-load scripts-directory
749 Set a list of directories from which to load auto-loaded scripts.
750 Automatically loaded Python scripts and GDB scripts are located in one
751 of the directories listed by this option.
752 The delimiter (':' above) may differ according to the host platform.
754 set auto-load safe-path <dir1>[:<dir2>...]
755 show auto-load safe-path
756 Set a list of directories from which it is safe to auto-load files.
757 The delimiter (':' above) may differ according to the host platform.
759 set debug auto-load on|off
761 Control display of debugging info for auto-loading the files above.
763 set dprintf-style gdb|call|agent
765 Control the way in which a dynamic printf is performed; "gdb"
766 requests a GDB printf command, while "call" causes dprintf to call a
767 function in the inferior. "agent" requests that the target agent
768 (such as GDBserver) do the printing.
770 set dprintf-function <expr>
771 show dprintf-function
772 set dprintf-channel <expr>
774 Set the function and optional first argument to the call when using
775 the "call" style of dynamic printf.
777 set disconnected-dprintf on|off
778 show disconnected-dprintf
779 Control whether agent-style dynamic printfs continue to be in effect
780 after GDB disconnects.
782 * New configure options
785 Configure default value for the 'set auto-load scripts-directory'
786 setting above. It defaults to '$debugdir:$datadir/auto-load',
787 $debugdir representing global debugging info directories (available
788 via 'show debug-file-directory') and $datadir representing GDB's data
789 directory (available via 'show data-directory').
791 --with-auto-load-safe-path
792 Configure default value for the 'set auto-load safe-path' setting
793 above. It defaults to the --with-auto-load-dir setting.
795 --without-auto-load-safe-path
796 Set 'set auto-load safe-path' to '/', effectively disabling this
801 z0/z1 conditional breakpoints extension
803 The z0/z1 breakpoint insertion packets have been extended to carry
804 a list of conditional expressions over to the remote stub depending on the
805 condition evaluation mode. The use of this extension can be controlled
806 via the "set remote conditional-breakpoints-packet" command.
810 Specify the signals which the remote stub may pass to the debugged
811 program without GDB involvement.
813 * New command line options
815 --init-command=FILE, -ix Like --command, -x but execute it
816 before loading inferior.
817 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
818 execute it before loading inferior.
820 *** Changes in GDB 7.4
822 * GDB now handles ambiguous linespecs more consistently; the existing
823 FILE:LINE support has been expanded to other types of linespecs. A
824 breakpoint will now be set on all matching locations in all
825 inferiors, and locations will be added or removed according to
828 * GDB now allows you to skip uninteresting functions and files when
829 stepping with the "skip function" and "skip file" commands.
831 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
832 and "show remote hardware-watchpoint-length-limit". These allows to
833 set or show the maximum length limit (in bytes) of a remote
834 target hardware watchpoint.
836 This allows e.g. to use "unlimited" hardware watchpoints with the
837 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
838 watchpoints are slower than real hardware watchpoints but are
839 significantly faster than gdb software watchpoints.
843 ** The register_pretty_printer function in module gdb.printing now takes
844 an optional `replace' argument. If True, the new printer replaces any
847 ** The "maint set python print-stack on|off" command has been
848 deprecated and will be deleted in GDB 7.5.
849 A new command: "set python print-stack none|full|message" has
850 replaced it. Additionally, the default for "print-stack" is
851 now "message", which just prints the error message without
854 ** A prompt substitution hook (prompt_hook) is now available to the
857 ** A new Python module, gdb.prompt has been added to the GDB Python
858 modules library. This module provides functionality for
859 escape sequences in prompts (used by set/show
860 extended-prompt). These escape sequences are replaced by their
863 ** Python commands and convenience-functions located in
864 'data-directory'/python/gdb/command and
865 'data-directory'/python/gdb/function are now automatically loaded
868 ** Blocks now provide four new attributes. global_block and
869 static_block will return the global and static blocks
870 respectively. is_static and is_global are boolean attributes
871 that indicate if the block is one of those two types.
873 ** Symbols now provide the "type" attribute, the type of the symbol.
875 ** The "gdb.breakpoint" function has been deprecated in favor of
878 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
879 of a function. This class is based on the "finish" command
880 available in the CLI.
882 ** Type objects for struct and union types now allow access to
883 the fields using standard Python dictionary (mapping) methods.
884 For example, "some_type['myfield']" now works, as does
887 ** A new event "gdb.new_objfile" has been added, triggered by loading a
890 ** A new function, "deep_items" has been added to the gdb.types
891 module in the GDB Python modules library. This function returns
892 an iterator over the fields of a struct or union type. Unlike
893 the standard Python "iteritems" method, it will recursively traverse
894 any anonymous fields.
898 ** "*stopped" events can report several new "reason"s, such as
901 ** Breakpoint changes are now notified using new async records, like
902 "=breakpoint-modified".
904 ** New command -ada-task-info.
906 * libthread-db-search-path now supports two special values: $sdir and $pdir.
907 $sdir specifies the default system locations of shared libraries.
908 $pdir specifies the directory where the libpthread used by the application
911 GDB no longer looks in $sdir and $pdir after it has searched the directories
912 mentioned in libthread-db-search-path. If you want to search those
913 directories, they must be specified in libthread-db-search-path.
914 The default value of libthread-db-search-path on GNU/Linux and Solaris
915 systems is now "$sdir:$pdir".
917 $pdir is not supported by gdbserver, it is currently ignored.
918 $sdir is supported by gdbserver.
920 * New configure option --with-iconv-bin.
921 When using the internationalization support like the one in the GNU C
922 library, GDB will invoke the "iconv" program to get a list of supported
923 character sets. If this program lives in a non-standard location, one can
924 use this option to specify where to find it.
926 * When natively debugging programs on PowerPC BookE processors running
927 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
928 watchpoints, which specify a mask in addition to an address to watch.
929 The mask specifies that some bits of an address (the bits which are
930 reset in the mask) should be ignored when matching the address accessed
931 by the inferior against the watchpoint address. See the "PowerPC Embedded"
932 section in the user manual for more details.
934 * The new option --once causes GDBserver to stop listening for connections once
935 the first connection is made. The listening port used by GDBserver will
936 become available after that.
938 * New commands "info macros" and "alias" have been added.
940 * New function parameters suffix @entry specifies value of function parameter
941 at the time the function got called. Entry values are available only since
947 "!" is now an alias of the "shell" command.
948 Note that no space is needed between "!" and SHELL COMMAND.
952 watch EXPRESSION mask MASK_VALUE
953 The watch command now supports the mask argument which allows creation
954 of masked watchpoints, if the current architecture supports this feature.
956 info auto-load-scripts [REGEXP]
957 This command was formerly named "maintenance print section-scripts".
958 It is now generally useful and is no longer a maintenance-only command.
960 info macro [-all] [--] MACRO
961 The info macro command has new options `-all' and `--'. The first for
962 printing all definitions of a macro. The second for explicitly specifying
963 the end of arguments and the beginning of the macro name in case the macro
964 name starts with a hyphen.
966 collect[/s] EXPRESSIONS
967 The tracepoint collect command now takes an optional modifier "/s"
968 that directs it to dereference pointer-to-character types and
969 collect the bytes of memory up to a zero byte. The behavior is
970 similar to what you see when you use the regular print command on a
971 string. An optional integer following the "/s" sets a bound on the
972 number of bytes that will be collected.
975 The trace start command now interprets any supplied arguments as a
976 note to be recorded with the trace run, with an effect similar to
977 setting the variable trace-notes.
980 The trace stop command now interprets any arguments as a note to be
981 mentioned along with the tstatus report that the trace was stopped
982 with a command. The effect is similar to setting the variable
985 * Tracepoints can now be enabled and disabled at any time after a trace
986 experiment has been started using the standard "enable" and "disable"
987 commands. It is now possible to start a trace experiment with no enabled
988 tracepoints; GDB will display a warning, but will allow the experiment to
989 begin, assuming that tracepoints will be enabled as needed while the trace
992 * Fast tracepoints on 32-bit x86-architectures can now be placed at
993 locations with 4-byte instructions, when they were previously
994 limited to locations with instructions of 5 bytes or longer.
998 set debug dwarf2-read
999 show debug dwarf2-read
1000 Turns on or off display of debugging messages related to reading
1001 DWARF debug info. The default is off.
1003 set debug symtab-create
1004 show debug symtab-create
1005 Turns on or off display of debugging messages related to symbol table
1006 creation. The default is off.
1009 show extended-prompt
1010 Set the GDB prompt, and allow escape sequences to be inserted to
1011 display miscellaneous information (see 'help set extended-prompt'
1012 for the list of sequences). This prompt (and any information
1013 accessed through the escape sequences) is updated every time the
1014 prompt is displayed.
1016 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1017 show print entry-values
1018 Set printing of frame argument values at function entry. In some cases
1019 GDB can determine the value of function argument which was passed by the
1020 function caller, even if the value was modified inside the called function.
1022 set debug entry-values
1023 show debug entry-values
1024 Control display of debugging info for determining frame argument values at
1025 function entry and virtual tail call frames.
1027 set basenames-may-differ
1028 show basenames-may-differ
1029 Set whether a source file may have multiple base names.
1030 (A "base name" is the name of a file with the directory part removed.
1031 Example: The base name of "/home/user/hello.c" is "hello.c".)
1032 If set, GDB will canonicalize file names (e.g., expand symlinks)
1033 before comparing them. Canonicalization is an expensive operation,
1034 but it allows the same file be known by more than one base name.
1035 If not set (the default), all source files are assumed to have just
1036 one base name, and gdb will do file name comparisons more efficiently.
1042 Set a user name and notes for the current and any future trace runs.
1043 This is useful for long-running and/or disconnected traces, to
1044 inform others (or yourself) as to who is running the trace, supply
1045 contact information, or otherwise explain what is going on.
1047 set trace-stop-notes
1048 show trace-stop-notes
1049 Set a note attached to the trace run, that is displayed when the
1050 trace has been stopped by a tstop command. This is useful for
1051 instance as an explanation, if you are stopping a trace run that was
1052 started by someone else.
1054 * New remote packets
1058 Dynamically enable a tracepoint in a started trace experiment.
1062 Dynamically disable a tracepoint in a started trace experiment.
1066 Set the user and notes of the trace run.
1070 Query the current status of a tracepoint.
1074 Query the minimum length of instruction at which a fast tracepoint may
1077 * Dcache size (number of lines) and line-size are now runtime-configurable
1078 via "set dcache line" and "set dcache line-size" commands.
1082 Texas Instruments TMS320C6x tic6x-*-*
1086 Renesas RL78 rl78-*-elf
1088 *** Changes in GDB 7.3.1
1090 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1092 *** Changes in GDB 7.3
1094 * GDB has a new command: "thread find [REGEXP]".
1095 It finds the thread id whose name, target id, or thread extra info
1096 matches the given regular expression.
1098 * The "catch syscall" command now works on mips*-linux* targets.
1100 * The -data-disassemble MI command now supports modes 2 and 3 for
1101 dumping the instruction opcodes.
1103 * New command line options
1105 -data-directory DIR Specify DIR as the "data-directory".
1106 This is mostly for testing purposes.
1108 * The "maint set python auto-load on|off" command has been renamed to
1109 "set auto-load-scripts on|off".
1111 * GDB has a new command: "set directories".
1112 It is like the "dir" command except that it replaces the
1113 source path list instead of augmenting it.
1115 * GDB now understands thread names.
1117 On GNU/Linux, "info threads" will display the thread name as set by
1118 prctl or pthread_setname_np.
1120 There is also a new command, "thread name", which can be used to
1121 assign a name internally for GDB to display.
1124 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1125 has been integrated into GDB.
1129 ** The function gdb.Write now accepts an optional keyword 'stream'.
1130 This keyword, when provided, will direct the output to either
1131 stdout, stderr, or GDB's logging output.
1133 ** Parameters can now be be sub-classed in Python, and in particular
1134 you may implement the get_set_doc and get_show_doc functions.
1135 This improves how Parameter set/show documentation is processed
1136 and allows for more dynamic content.
1138 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1139 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1140 have an is_valid method.
1142 ** Breakpoints can now be sub-classed in Python, and in particular
1143 you may implement a 'stop' function that is executed each time
1144 the inferior reaches that breakpoint.
1146 ** New function gdb.lookup_global_symbol looks up a global symbol.
1148 ** GDB values in Python are now callable if the value represents a
1149 function. For example, if 'some_value' represents a function that
1150 takes two integer parameters and returns a value, you can call
1151 that function like so:
1153 result = some_value (10,20)
1155 ** Module gdb.types has been added.
1156 It contains a collection of utilities for working with gdb.Types objects:
1157 get_basic_type, has_field, make_enum_dict.
1159 ** Module gdb.printing has been added.
1160 It contains utilities for writing and registering pretty-printers.
1161 New classes: PrettyPrinter, SubPrettyPrinter,
1162 RegexpCollectionPrettyPrinter.
1163 New function: register_pretty_printer.
1165 ** New commands "info pretty-printers", "enable pretty-printer" and
1166 "disable pretty-printer" have been added.
1168 ** gdb.parameter("directories") is now available.
1170 ** New function gdb.newest_frame returns the newest frame in the
1173 ** The gdb.InferiorThread class has a new "name" attribute. This
1174 holds the thread's name.
1176 ** Python Support for Inferior events.
1177 Python scripts can add observers to be notified of events
1178 occurring in the process being debugged.
1179 The following events are currently supported:
1180 - gdb.events.cont Continue event.
1181 - gdb.events.exited Inferior exited event.
1182 - gdb.events.stop Signal received, and Breakpoint hit events.
1186 ** GDB now puts template parameters in scope when debugging in an
1187 instantiation. For example, if you have:
1189 template<int X> int func (void) { return X; }
1191 then if you step into func<5>, "print X" will show "5". This
1192 feature requires proper debuginfo support from the compiler; it
1193 was added to GCC 4.5.
1195 ** The motion commands "next", "finish", "until", and "advance" now
1196 work better when exceptions are thrown. In particular, GDB will
1197 no longer lose control of the inferior; instead, the GDB will
1198 stop the inferior at the point at which the exception is caught.
1199 This functionality requires a change in the exception handling
1200 code that was introduced in GCC 4.5.
1202 * GDB now follows GCC's rules on accessing volatile objects when
1203 reading or writing target state during expression evaluation.
1204 One notable difference to prior behavior is that "print x = 0"
1205 no longer generates a read of x; the value of the assignment is
1206 now always taken directly from the value being assigned.
1208 * GDB now has some support for using labels in the program's source in
1209 linespecs. For instance, you can use "advance label" to continue
1210 execution to a label.
1212 * GDB now has support for reading and writing a new .gdb_index
1213 section. This section holds a fast index of DWARF debugging
1214 information and can be used to greatly speed up GDB startup and
1215 operation. See the documentation for `save gdb-index' for details.
1217 * The "watch" command now accepts an optional "-location" argument.
1218 When used, this causes GDB to watch the memory referred to by the
1219 expression. Such a watchpoint is never deleted due to it going out
1222 * GDB now supports thread debugging of core dumps on GNU/Linux.
1224 GDB now activates thread debugging using the libthread_db library
1225 when debugging GNU/Linux core dumps, similarly to when debugging
1226 live processes. As a result, when debugging a core dump file, GDB
1227 is now able to display pthread_t ids of threads. For example, "info
1228 threads" shows the same output as when debugging the process when it
1229 was live. In earlier releases, you'd see something like this:
1232 * 1 LWP 6780 main () at main.c:10
1234 While now you see this:
1237 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1239 It is also now possible to inspect TLS variables when debugging core
1242 When debugging a core dump generated on a machine other than the one
1243 used to run GDB, you may need to point GDB at the correct
1244 libthread_db library with the "set libthread-db-search-path"
1245 command. See the user manual for more details on this command.
1247 * When natively debugging programs on PowerPC BookE processors running
1248 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1249 which stop execution of the inferior whenever it executes an instruction
1250 at any address within the specified range. See the "PowerPC Embedded"
1251 section in the user manual for more details.
1253 * New features in the GDB remote stub, GDBserver
1255 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1256 and i686 LynxOS (version 5.x).
1258 ** GDBserver is now supported on Blackfin Linux.
1260 * New native configurations
1262 ia64 HP-UX ia64-*-hpux*
1266 Analog Devices, Inc. Blackfin Processor bfin-*
1268 * Ada task switching is now supported on sparc-elf targets when
1269 debugging a program using the Ravenscar Profile. For more information,
1270 see the "Tasking Support when using the Ravenscar Profile" section
1271 in the GDB user manual.
1273 * Guile support was removed.
1275 * New features in the GNU simulator
1277 ** The --map-info flag lists all known core mappings.
1279 ** CFI flashes may be simulated via the "cfi" device.
1281 *** Changes in GDB 7.2
1283 * Shared library support for remote targets by default
1285 When GDB is configured for a generic, non-OS specific target, like
1286 for example, --target=arm-eabi or one of the many *-*-elf targets,
1287 GDB now queries remote stubs for loaded shared libraries using the
1288 `qXfer:libraries:read' packet. Previously, shared library support
1289 was always disabled for such configurations.
1293 ** Argument Dependent Lookup (ADL)
1295 In C++ ADL lookup directs function search to the namespaces of its
1296 arguments even if the namespace has not been imported.
1306 Here the compiler will search for `foo' in the namespace of 'b'
1307 and find A::foo. GDB now supports this. This construct is commonly
1308 used in the Standard Template Library for operators.
1310 ** Improved User Defined Operator Support
1312 In addition to member operators, GDB now supports lookup of operators
1313 defined in a namespace and imported with a `using' directive, operators
1314 defined in the global scope, operators imported implicitly from an
1315 anonymous namespace, and the ADL operators mentioned in the previous
1317 GDB now also supports proper overload resolution for all the previously
1318 mentioned flavors of operators.
1320 ** static const class members
1322 Printing of static const class members that are initialized in the
1323 class definition has been fixed.
1325 * Windows Thread Information Block access.
1327 On Windows targets, GDB now supports displaying the Windows Thread
1328 Information Block (TIB) structure. This structure is visible either
1329 by using the new command `info w32 thread-information-block' or, by
1330 dereferencing the new convenience variable named `$_tlb', a
1331 thread-specific pointer to the TIB. This feature is also supported
1332 when remote debugging using GDBserver.
1334 * Static tracepoints
1336 Static tracepoints are calls in the user program into a tracing
1337 library. One such library is a port of the LTTng kernel tracer to
1338 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1339 When debugging with GDBserver, GDB now supports combining the GDB
1340 tracepoint machinery with such libraries. For example: the user can
1341 use GDB to probe a static tracepoint marker (a call from the user
1342 program into the tracing library) with the new "strace" command (see
1343 "New commands" below). This creates a "static tracepoint" in the
1344 breakpoint list, that can be manipulated with the same feature set
1345 as fast and regular tracepoints. E.g., collect registers, local and
1346 global variables, collect trace state variables, and define
1347 tracepoint conditions. In addition, the user can collect extra
1348 static tracepoint marker specific data, by collecting the new
1349 $_sdata internal variable. When analyzing the trace buffer, you can
1350 inspect $_sdata like any other variable available to GDB. For more
1351 information, see the "Tracepoints" chapter in GDB user manual. New
1352 remote packets have been defined to support static tracepoints, see
1353 the "New remote packets" section below.
1355 * Better reconstruction of tracepoints after disconnected tracing
1357 GDB will attempt to download the original source form of tracepoint
1358 definitions when starting a trace run, and then will upload these
1359 upon reconnection to the target, resulting in a more accurate
1360 reconstruction of the tracepoints that are in use on the target.
1364 You can now exercise direct control over the ways that GDB can
1365 affect your program. For instance, you can disallow the setting of
1366 breakpoints, so that the program can run continuously (assuming
1367 non-stop mode). In addition, the "observer" variable is available
1368 to switch all of the different controls; in observer mode, GDB
1369 cannot affect the target's behavior at all, which is useful for
1370 tasks like diagnosing live systems in the field.
1372 * The new convenience variable $_thread holds the number of the
1375 * New remote packets
1379 Return the address of the Windows Thread Information Block of a given thread.
1383 In response to several of the tracepoint packets, the target may now
1384 also respond with a number of intermediate `qRelocInsn' request
1385 packets before the final result packet, to have GDB handle
1386 relocating an instruction to execute at a different address. This
1387 is particularly useful for stubs that support fast tracepoints. GDB
1388 reports support for this feature in the qSupported packet.
1392 List static tracepoint markers in the target program.
1396 List static tracepoint markers at a given address in the target
1399 qXfer:statictrace:read
1401 Read the static trace data collected (by a `collect $_sdata'
1402 tracepoint action). The remote stub reports support for this packet
1403 to gdb's qSupported query.
1407 Send the current settings of GDB's permission flags.
1411 Send part of the source (textual) form of a tracepoint definition,
1412 which includes location, conditional, and action list.
1414 * The source command now accepts a -s option to force searching for the
1415 script in the source search path even if the script name specifies
1418 * New features in the GDB remote stub, GDBserver
1420 - GDBserver now support tracepoints (including fast tracepoints, and
1421 static tracepoints). The feature is currently supported by the
1422 i386-linux and amd64-linux builds. See the "Tracepoints support
1423 in gdbserver" section in the manual for more information.
1425 GDBserver JIT compiles the tracepoint's conditional agent
1426 expression bytecode into native code whenever possible for low
1427 overhead dynamic tracepoints conditionals. For such tracepoints,
1428 an expression that examines program state is evaluated when the
1429 tracepoint is reached, in order to determine whether to capture
1430 trace data. If the condition is simple and false, processing the
1431 tracepoint finishes very quickly and no data is gathered.
1433 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1434 for static tracepoints support.
1436 - GDBserver now supports x86_64 Windows 64-bit debugging.
1438 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1439 it understands register description.
1441 * The --batch flag now disables pagination and queries.
1443 * X86 general purpose registers
1445 GDB now supports reading/writing byte, word and double-word x86
1446 general purpose registers directly. This means you can use, say,
1447 $ah or $ax to refer, respectively, to the byte register AH and
1448 16-bit word register AX that are actually portions of the 32-bit
1449 register EAX or 64-bit register RAX.
1451 * The `commands' command now accepts a range of breakpoints to modify.
1452 A plain `commands' following a command that creates multiple
1453 breakpoints affects all the breakpoints set by that command. This
1454 applies to breakpoints set by `rbreak', and also applies when a
1455 single `break' command creates multiple breakpoints (e.g.,
1456 breakpoints on overloaded c++ functions).
1458 * The `rbreak' command now accepts a filename specification as part of
1459 its argument, limiting the functions selected by the regex to those
1460 in the specified file.
1462 * Support for remote debugging Windows and SymbianOS shared libraries
1463 from Unix hosts has been improved. Non Windows GDB builds now can
1464 understand target reported file names that follow MS-DOS based file
1465 system semantics, such as file names that include drive letters and
1466 use the backslash character as directory separator. This makes it
1467 possible to transparently use the "set sysroot" and "set
1468 solib-search-path" on Unix hosts to point as host copies of the
1469 target's shared libraries. See the new command "set
1470 target-file-system-kind" described below, and the "Commands to
1471 specify files" section in the user manual for more information.
1475 eval template, expressions...
1476 Convert the values of one or more expressions under the control
1477 of the string template to a command line, and call it.
1479 set target-file-system-kind unix|dos-based|auto
1480 show target-file-system-kind
1481 Set or show the assumed file system kind for target reported file
1484 save breakpoints <filename>
1485 Save all current breakpoint definitions to a file suitable for use
1486 in a later debugging session. To read the saved breakpoint
1487 definitions, use the `source' command.
1489 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1492 info static-tracepoint-markers
1493 Display information about static tracepoint markers in the target.
1495 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1496 Define a static tracepoint by probing a marker at the given
1497 function, line, address, or marker ID.
1501 Enable and disable observer mode.
1503 set may-write-registers on|off
1504 set may-write-memory on|off
1505 set may-insert-breakpoints on|off
1506 set may-insert-tracepoints on|off
1507 set may-insert-fast-tracepoints on|off
1508 set may-interrupt on|off
1509 Set individual permissions for GDB effects on the target. Note that
1510 some of these settings can have undesirable or surprising
1511 consequences, particularly when changed in the middle of a session.
1512 For instance, disabling the writing of memory can prevent
1513 breakpoints from being inserted, cause single-stepping to fail, or
1514 even crash your program, if you disable after breakpoints have been
1515 inserted. However, GDB should not crash.
1517 set record memory-query on|off
1518 show record memory-query
1519 Control whether to stop the inferior if memory changes caused
1520 by an instruction cannot be recorded.
1525 The disassemble command now supports "start,+length" form of two arguments.
1529 ** GDB now provides a new directory location, called the python directory,
1530 where Python scripts written for GDB can be installed. The location
1531 of that directory is <data-directory>/python, where <data-directory>
1532 is the GDB data directory. For more details, see section `Scripting
1533 GDB using Python' in the manual.
1535 ** The GDB Python API now has access to breakpoints, symbols, symbol
1536 tables, program spaces, inferiors, threads and frame's code blocks.
1537 Additionally, GDB Parameters can now be created from the API, and
1538 manipulated via set/show in the CLI.
1540 ** New functions gdb.target_charset, gdb.target_wide_charset,
1541 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1543 ** New exception gdb.GdbError.
1545 ** Pretty-printers are now also looked up in the current program space.
1547 ** Pretty-printers can now be individually enabled and disabled.
1549 ** GDB now looks for names of Python scripts to auto-load in a
1550 special section named `.debug_gdb_scripts', in addition to looking
1551 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1553 * Tracepoint actions were unified with breakpoint commands. In particular,
1554 there are no longer differences in "info break" output for breakpoints and
1555 tracepoints and the "commands" command can be used for both tracepoints and
1556 regular breakpoints.
1560 ARM Symbian arm*-*-symbianelf*
1562 * D language support.
1563 GDB now supports debugging programs written in the D programming
1566 * GDB now supports the extended ptrace interface for PowerPC which is
1567 available since Linux kernel version 2.6.34. This automatically enables
1568 any hardware breakpoints and additional hardware watchpoints available in
1569 the processor. The old ptrace interface exposes just one hardware
1570 watchpoint and no hardware breakpoints.
1572 * GDB is now able to use the Data Value Compare (DVC) register available on
1573 embedded PowerPC processors to implement in hardware simple watchpoint
1574 conditions of the form:
1576 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1578 This works in native GDB running on Linux kernels with the extended ptrace
1579 interface mentioned above.
1581 *** Changes in GDB 7.1
1585 ** Namespace Support
1587 GDB now supports importing of namespaces in C++. This enables the
1588 user to inspect variables from imported namespaces. Support for
1589 namepace aliasing has also been added. So, if a namespace is
1590 aliased in the current scope (e.g. namepace C=A; ) the user can
1591 print variables using the alias (e.g. (gdb) print C::x).
1595 All known bugs relating to the printing of virtual base class were
1596 fixed. It is now possible to call overloaded static methods using a
1601 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1602 and reinterpret_cast<> are now handled by the C++ expression parser.
1606 Xilinx MicroBlaze microblaze-*-*
1611 Xilinx MicroBlaze microblaze
1614 * Multi-program debugging.
1616 GDB now has support for multi-program (a.k.a. multi-executable or
1617 multi-exec) debugging. This allows for debugging multiple inferiors
1618 simultaneously each running a different program under the same GDB
1619 session. See "Debugging Multiple Inferiors and Programs" in the
1620 manual for more information. This implied some user visible changes
1621 in the multi-inferior support. For example, "info inferiors" now
1622 lists inferiors that are not running yet or that have exited
1623 already. See also "New commands" and "New options" below.
1625 * New tracing features
1627 GDB's tracepoint facility now includes several new features:
1629 ** Trace state variables
1631 GDB tracepoints now include support for trace state variables, which
1632 are variables managed by the target agent during a tracing
1633 experiment. They are useful for tracepoints that trigger each
1634 other, so for instance one tracepoint can count hits in a variable,
1635 and then a second tracepoint has a condition that is true when the
1636 count reaches a particular value. Trace state variables share the
1637 $-syntax of GDB convenience variables, and can appear in both
1638 tracepoint actions and condition expressions. Use the "tvariable"
1639 command to create, and "info tvariables" to view; see "Trace State
1640 Variables" in the manual for more detail.
1644 GDB now includes an option for defining fast tracepoints, which
1645 targets may implement more efficiently, such as by installing a jump
1646 into the target agent rather than a trap instruction. The resulting
1647 speedup can be by two orders of magnitude or more, although the
1648 tradeoff is that some program locations on some target architectures
1649 might not allow fast tracepoint installation, for instance if the
1650 instruction to be replaced is shorter than the jump. To request a
1651 fast tracepoint, use the "ftrace" command, with syntax identical to
1652 the regular trace command.
1654 ** Disconnected tracing
1656 It is now possible to detach GDB from the target while it is running
1657 a trace experiment, then reconnect later to see how the experiment
1658 is going. In addition, a new variable disconnected-tracing lets you
1659 tell the target agent whether to continue running a trace if the
1660 connection is lost unexpectedly.
1664 GDB now has the ability to save the trace buffer into a file, and
1665 then use that file as a target, similarly to you can do with
1666 corefiles. You can select trace frames, print data that was
1667 collected in them, and use tstatus to display the state of the
1668 tracing run at the moment that it was saved. To create a trace
1669 file, use "tsave <filename>", and to use it, do "target tfile
1672 ** Circular trace buffer
1674 You can ask the target agent to handle the trace buffer as a
1675 circular buffer, discarding the oldest trace frames to make room for
1676 newer ones, by setting circular-trace-buffer to on. This feature may
1677 not be available for all target agents.
1682 The disassemble command, when invoked with two arguments, now requires
1683 the arguments to be comma-separated.
1686 The info variables command now displays variable definitions. Files
1687 which only declare a variable are not shown.
1690 The source command is now capable of sourcing Python scripts.
1691 This feature is dependent on the debugger being build with Python
1694 Related to this enhancement is also the introduction of a new command
1695 "set script-extension" (see below).
1697 * New commands (for set/show, see "New options" below)
1699 record save [<FILENAME>]
1700 Save a file (in core file format) containing the process record
1701 execution log for replay debugging at a later time.
1703 record restore <FILENAME>
1704 Restore the process record execution log that was saved at an
1705 earlier time, for replay debugging.
1707 add-inferior [-copies <N>] [-exec <FILENAME>]
1710 clone-inferior [-copies <N>] [ID]
1711 Make a new inferior ready to execute the same program another
1712 inferior has loaded.
1717 maint info program-spaces
1718 List the program spaces loaded into GDB.
1720 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1721 show remote interrupt-sequence
1722 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1723 as the sequence to the remote target in order to interrupt the execution.
1724 Ctrl-C is a default. Some system prefers BREAK which is high level of
1725 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1726 Magic SysRq g. It is BREAK signal and character 'g'.
1728 set remote interrupt-on-connect [on | off]
1729 show remote interrupt-on-connect
1730 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1731 remote target when gdb connects to it. This is needed when you debug
1734 set remotebreak [on | off]
1736 Deprecated. Use "set/show remote interrupt-sequence" instead.
1738 tvariable $NAME [ = EXP ]
1739 Create or modify a trace state variable.
1742 List trace state variables and their values.
1744 delete tvariable $NAME ...
1745 Delete one or more trace state variables.
1748 Evaluate the given expressions without collecting anything into the
1749 trace buffer. (Valid in tracepoint actions only.)
1751 ftrace FN / FILE:LINE / *ADDR
1752 Define a fast tracepoint at the given function, line, or address.
1754 * New expression syntax
1756 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1757 GDB now parses 0b101010 identically with 42.
1761 set follow-exec-mode new|same
1762 show follow-exec-mode
1763 Control whether GDB reuses the same inferior across an exec call or
1764 creates a new one. This is useful to be able to restart the old
1765 executable after the inferior having done an exec call.
1767 set default-collect EXPR, ...
1768 show default-collect
1769 Define a list of expressions to be collected at each tracepoint.
1770 This is a useful way to ensure essential items are not overlooked,
1771 such as registers or a critical global variable.
1773 set disconnected-tracing
1774 show disconnected-tracing
1775 If set to 1, the target is instructed to continue tracing if it
1776 loses its connection to GDB. If 0, the target is to stop tracing
1779 set circular-trace-buffer
1780 show circular-trace-buffer
1781 If set to on, the target is instructed to use a circular trace buffer
1782 and discard the oldest trace frames instead of stopping the trace due
1783 to a full trace buffer. If set to off, the trace stops when the buffer
1784 fills up. Some targets may not support this.
1786 set script-extension off|soft|strict
1787 show script-extension
1788 If set to "off", the debugger does not perform any script language
1789 recognition, and all sourced files are assumed to be GDB scripts.
1790 If set to "soft" (the default), files are sourced according to
1791 filename extension, falling back to GDB scripts if the first
1793 If set to "strict", files are sourced according to filename extension.
1795 set ada trust-PAD-over-XVS on|off
1796 show ada trust-PAD-over-XVS
1797 If off, activate a workaround against a bug in the debugging information
1798 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1799 the GCC sources for more information about the GNAT encoding and
1800 PAD types in particular). It is always safe to set this option to
1801 off, but this introduces a slight performance penalty. The default
1804 * Python API Improvements
1806 ** GDB provides the new class gdb.LazyString. This is useful in
1807 some pretty-printing cases. The new method gdb.Value.lazy_string
1808 provides a simple way to create objects of this type.
1810 ** The fields returned by gdb.Type.fields now have an
1811 `is_base_class' attribute.
1813 ** The new method gdb.Type.range returns the range of an array type.
1815 ** The new method gdb.parse_and_eval can be used to parse and
1816 evaluate an expression.
1818 * New remote packets
1821 Define a trace state variable.
1824 Get the current value of a trace state variable.
1827 Set desired tracing behavior upon disconnection.
1830 Set the trace buffer to be linear or circular.
1833 Get data about the tracepoints currently in use.
1837 Process record now works correctly with hardware watchpoints.
1839 Multiple bug fixes have been made to the mips-irix port, making it
1840 much more reliable. In particular:
1841 - Debugging threaded applications is now possible again. Previously,
1842 GDB would hang while starting the program, or while waiting for
1843 the program to stop at a breakpoint.
1844 - Attaching to a running process no longer hangs.
1845 - An error occurring while loading a core file has been fixed.
1846 - Changing the value of the PC register now works again. This fixes
1847 problems observed when using the "jump" command, or when calling
1848 a function from GDB, or even when assigning a new value to $pc.
1849 - With the "finish" and "return" commands, the return value for functions
1850 returning a small array is now correctly printed.
1851 - It is now possible to break on shared library code which gets executed
1852 during a shared library init phase (code executed while executing
1853 their .init section). Previously, the breakpoint would have no effect.
1854 - GDB is now able to backtrace through the signal handler for
1855 non-threaded programs.
1857 PIE (Position Independent Executable) programs debugging is now supported.
1858 This includes debugging execution of PIC (Position Independent Code) shared
1859 libraries although for that, it should be possible to run such libraries as an
1862 *** Changes in GDB 7.0
1864 * GDB now has an interface for JIT compilation. Applications that
1865 dynamically generate code can create symbol files in memory and register
1866 them with GDB. For users, the feature should work transparently, and
1867 for JIT developers, the interface is documented in the GDB manual in the
1868 "JIT Compilation Interface" chapter.
1870 * Tracepoints may now be conditional. The syntax is as for
1871 breakpoints; either an "if" clause appended to the "trace" command,
1872 or the "condition" command is available. GDB sends the condition to
1873 the target for evaluation using the same bytecode format as is used
1874 for tracepoint actions.
1876 * The disassemble command now supports: an optional /r modifier, print the
1877 raw instructions in hex as well as in symbolic form, and an optional /m
1878 modifier to print mixed source+assembly.
1880 * Process record and replay
1882 In a architecture environment that supports ``process record and
1883 replay'', ``process record and replay'' target can record a log of
1884 the process execution, and replay it with both forward and reverse
1887 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1888 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1889 set execution-direction {forward|reverse}, for targets that support
1892 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1893 feature is available with a native GDB running on kernel version
1896 * GDB now has support for multi-byte and wide character sets on the
1897 target. Strings whose character type is wchar_t, char16_t, or
1898 char32_t are now correctly printed. GDB supports wide- and unicode-
1899 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1900 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1901 `printf'. This feature requires iconv to work properly; if your
1902 system does not have a working iconv, GDB can use GNU libiconv. See
1903 the installation instructions for more information.
1905 * GDB now supports automatic retrieval of shared library files from
1906 remote targets. To use this feature, specify a system root that begins
1907 with the `remote:' prefix, either via the `set sysroot' command or via
1908 the `--with-sysroot' configure-time option.
1910 * "info sharedlibrary" now takes an optional regex of libraries to show,
1911 and it now reports if a shared library has no debugging information.
1913 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1914 now complete on file names.
1916 * When completing in expressions, gdb will attempt to limit
1917 completions to allowable structure or union fields, where appropriate.
1918 For instance, consider:
1920 # struct example { int f1; double f2; };
1921 # struct example variable;
1924 If the user types TAB at the end of this command line, the available
1925 completions will be "f1" and "f2".
1927 * Inlined functions are now supported. They show up in backtraces, and
1928 the "step", "next", and "finish" commands handle them automatically.
1930 * GDB now supports the token-splicing (##) and stringification (#)
1931 operators when expanding macros. It also supports variable-arity
1934 * GDB now supports inspecting extra signal information, exported by
1935 the new $_siginfo convenience variable. The feature is currently
1936 implemented on linux ARM, i386 and amd64.
1938 * GDB can now display the VFP floating point registers and NEON vector
1939 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1940 can provide these registers (requires Linux 2.6.30 or later). Remote
1941 and simulator targets may also provide them.
1943 * New remote packets
1946 Search memory for a sequence of bytes.
1949 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1950 operation over reliable transport links. Use of this packet is
1951 controlled by the `set remote noack-packet' command.
1954 Kill the process with the specified process ID. Use this in preference
1955 to `k' when multiprocess protocol extensions are supported.
1958 Obtains additional operating system information
1962 Read or write additional signal information.
1964 * Removed remote protocol undocumented extension
1966 An undocumented extension to the remote protocol's `S' stop reply
1967 packet that permited the stub to pass a process id was removed.
1968 Remote servers should use the `T' stop reply packet instead.
1970 * GDB now supports multiple function calling conventions according to the
1971 DWARF-2 DW_AT_calling_convention function attribute.
1973 * The SH target utilizes the aforementioned change to distinguish between gcc
1974 and Renesas calling convention. It also adds the new CLI commands
1975 `set/show sh calling-convention'.
1977 * GDB can now read compressed debug sections, as produced by GNU gold
1978 with the --compress-debug-sections=zlib flag.
1980 * 64-bit core files are now supported on AIX.
1982 * Thread switching is now supported on Tru64.
1984 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1985 which will be allocated using malloc later in program execution.
1987 * The qXfer:libraries:read remote procotol packet now allows passing a
1988 list of section offsets.
1990 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1991 conditions handling signals delivered during attach or thread creation
1992 have also been fixed.
1994 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1995 From the user's standpoint, all unqualified instances of True and False
1996 are treated as the standard definitions, regardless of context.
1998 * GDB now parses C++ symbol and type names more flexibly. For
2001 template<typename T> class C { };
2004 GDB will now correctly handle all of:
2006 ptype C<char const *>
2007 ptype C<char const*>
2008 ptype C<const char *>
2009 ptype C<const char*>
2011 * New features in the GDB remote stub, gdbserver
2013 - The "--wrapper" command-line argument tells gdbserver to use a
2014 wrapper program to launch programs for debugging.
2016 - On PowerPC and S/390 targets, it is now possible to use a single
2017 gdbserver executable to debug both 32-bit and 64-bit programs.
2018 (This requires gdbserver itself to be built as a 64-bit executable.)
2020 - gdbserver uses the new noack protocol mode for TCP connections to
2021 reduce communications latency, if also supported and enabled in GDB.
2023 - Support for the sparc64-linux-gnu target is now included in
2026 - The amd64-linux build of gdbserver now supports debugging both
2027 32-bit and 64-bit programs.
2029 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2030 now support hardware watchpoints, and will use them automatically
2035 GDB now has support for scripting using Python. Whether this is
2036 available is determined at configure time.
2038 New GDB commands can now be written in Python.
2040 * Ada tasking support
2042 Ada tasks can now be inspected in GDB. The following commands have
2046 Print the list of Ada tasks.
2048 Print detailed information about task number N.
2050 Print the task number of the current task.
2052 Switch the context of debugging to task number N.
2054 * Support for user-defined prefixed commands. The "define" command can
2055 add new commands to existing prefixes, e.g. "target".
2057 * Multi-inferior, multi-process debugging.
2059 GDB now has generalized support for multi-inferior debugging. See
2060 "Debugging Multiple Inferiors" in the manual for more information.
2061 Although availability still depends on target support, the command
2062 set is more uniform now. The GNU/Linux specific multi-forks support
2063 has been migrated to this new framework. This implied some user
2064 visible changes; see "New commands" and also "Removed commands"
2067 * Target descriptions can now describe the target OS ABI. See the
2068 "Target Description Format" section in the user manual for more
2071 * Target descriptions can now describe "compatible" architectures
2072 to indicate that the target can execute applications for a different
2073 architecture in addition to those for the main target architecture.
2074 See the "Target Description Format" section in the user manual for
2077 * Multi-architecture debugging.
2079 GDB now includes general supports for debugging applications on
2080 hybrid systems that use more than one single processor architecture
2081 at the same time. Each such hybrid architecture still requires
2082 specific support to be added. The only hybrid architecture supported
2083 in this version of GDB is the Cell Broadband Engine.
2085 * GDB now supports integrated debugging of Cell/B.E. applications that
2086 use both the PPU and SPU architectures. To enable support for hybrid
2087 Cell/B.E. debugging, you need to configure GDB to support both the
2088 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2089 --enable-targets configure option.
2091 * Non-stop mode debugging.
2093 For some targets, GDB now supports an optional mode of operation in
2094 which you can examine stopped threads while other threads continue
2095 to execute freely. This is referred to as non-stop mode, with the
2096 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2097 section in the user manual for more information.
2099 To be able to support remote non-stop debugging, a remote stub needs
2100 to implement the non-stop mode remote protocol extensions, as
2101 described in the "Remote Non-Stop" section of the user manual. The
2102 GDB remote stub, gdbserver, has been adjusted to support these
2103 extensions on linux targets.
2105 * New commands (for set/show, see "New options" below)
2107 catch syscall [NAME(S) | NUMBER(S)]
2108 Catch system calls. Arguments, which should be names of system
2109 calls or their numbers, mean catch only those syscalls. Without
2110 arguments, every syscall will be caught. When the inferior issues
2111 any of the specified syscalls, GDB will stop and announce the system
2112 call, both when it is called and when its call returns. This
2113 feature is currently available with a native GDB running on the
2114 Linux Kernel, under the following architectures: x86, x86_64,
2115 PowerPC and PowerPC64.
2117 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2119 Search memory for a sequence of bytes.
2121 maint set python print-stack
2122 maint show python print-stack
2123 Show a stack trace when an error is encountered in a Python script.
2126 Invoke CODE by passing it to the Python interpreter.
2131 These allow macros to be defined, undefined, and listed
2135 Show operating system information about processes.
2138 List the inferiors currently under GDB's control.
2141 Switch focus to inferior number NUM.
2144 Detach from inferior number NUM.
2147 Kill inferior number NUM.
2151 set spu stop-on-load
2152 show spu stop-on-load
2153 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2155 set spu auto-flush-cache
2156 show spu auto-flush-cache
2157 Control whether to automatically flush the software-managed cache
2158 during Cell/B.E. debugging.
2160 set sh calling-convention
2161 show sh calling-convention
2162 Control the calling convention used when calling SH target functions.
2165 show debug timestamp
2166 Control display of timestamps with GDB debugging output.
2168 set disassemble-next-line
2169 show disassemble-next-line
2170 Control display of disassembled source lines or instructions when
2173 set remote noack-packet
2174 show remote noack-packet
2175 Set/show the use of remote protocol QStartNoAckMode packet. See above
2176 under "New remote packets."
2178 set remote query-attached-packet
2179 show remote query-attached-packet
2180 Control use of remote protocol `qAttached' (query-attached) packet.
2182 set remote read-siginfo-object
2183 show remote read-siginfo-object
2184 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2187 set remote write-siginfo-object
2188 show remote write-siginfo-object
2189 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2192 set remote reverse-continue
2193 show remote reverse-continue
2194 Control use of remote protocol 'bc' (reverse-continue) packet.
2196 set remote reverse-step
2197 show remote reverse-step
2198 Control use of remote protocol 'bs' (reverse-step) packet.
2200 set displaced-stepping
2201 show displaced-stepping
2202 Control displaced stepping mode. Displaced stepping is a way to
2203 single-step over breakpoints without removing them from the debuggee.
2204 Also known as "out-of-line single-stepping".
2207 show debug displaced
2208 Control display of debugging info for displaced stepping.
2210 maint set internal-error
2211 maint show internal-error
2212 Control what GDB does when an internal error is detected.
2214 maint set internal-warning
2215 maint show internal-warning
2216 Control what GDB does when an internal warning is detected.
2221 Use a wrapper program to launch programs for debugging.
2223 set multiple-symbols (all|ask|cancel)
2224 show multiple-symbols
2225 The value of this variable can be changed to adjust the debugger behavior
2226 when an expression or a breakpoint location contains an ambiguous symbol
2227 name (an overloaded function name, for instance).
2229 set breakpoint always-inserted
2230 show breakpoint always-inserted
2231 Keep breakpoints always inserted in the target, as opposed to inserting
2232 them when resuming the target, and removing them when the target stops.
2233 This option can improve debugger performance on slow remote targets.
2235 set arm fallback-mode (arm|thumb|auto)
2236 show arm fallback-mode
2237 set arm force-mode (arm|thumb|auto)
2239 These commands control how ARM GDB determines whether instructions
2240 are ARM or Thumb. The default for both settings is auto, which uses
2241 the current CPSR value for instructions without symbols; previous
2242 versions of GDB behaved as if "set arm fallback-mode arm".
2244 set disable-randomization
2245 show disable-randomization
2246 Standalone programs run with the virtual address space randomization enabled
2247 by default on some platforms. This option keeps the addresses stable across
2248 multiple debugging sessions.
2252 Control whether other threads are stopped or not when some thread hits
2257 Requests that asynchronous execution is enabled in the target, if available.
2258 In this case, it's possible to resume target in the background, and interact
2259 with GDB while the target is running. "show target-async" displays the
2260 current state of asynchronous execution of the target.
2262 set target-wide-charset
2263 show target-wide-charset
2264 The target-wide-charset is the name of the character set that GDB
2265 uses when printing characters whose type is wchar_t.
2267 set tcp auto-retry (on|off)
2269 set tcp connect-timeout
2270 show tcp connect-timeout
2271 These commands allow GDB to retry failed TCP connections to a remote stub
2272 with a specified timeout period; this is useful if the stub is launched
2273 in parallel with GDB but may not be ready to accept connections immediately.
2275 set libthread-db-search-path
2276 show libthread-db-search-path
2277 Control list of directories which GDB will search for appropriate
2280 set schedule-multiple (on|off)
2281 show schedule-multiple
2282 Allow GDB to resume all threads of all processes or only threads of
2283 the current process.
2287 Use more aggressive caching for accesses to the stack. This improves
2288 performance of remote debugging (particularly backtraces) without
2289 affecting correctness.
2291 set interactive-mode (on|off|auto)
2292 show interactive-mode
2293 Control whether GDB runs in interactive mode (on) or not (off).
2294 When in interactive mode, GDB waits for the user to answer all
2295 queries. Otherwise, GDB does not wait and assumes the default
2296 answer. When set to auto (the default), GDB determines which
2297 mode to use based on the stdin settings.
2302 For program forks, this is replaced by the new more generic `info
2303 inferiors' command. To list checkpoints, you can still use the
2304 `info checkpoints' command, which was an alias for the `info forks'
2308 Replaced by the new `inferior' command. To switch between
2309 checkpoints, you can still use the `restart' command, which was an
2310 alias for the `fork' command.
2313 This is removed, since some targets don't have a notion of
2314 processes. To switch between processes, you can still use the
2315 `inferior' command using GDB's own inferior number.
2318 For program forks, this is replaced by the new more generic `kill
2319 inferior' command. To delete a checkpoint, you can still use the
2320 `delete checkpoint' command, which was an alias for the `delete
2324 For program forks, this is replaced by the new more generic `detach
2325 inferior' command. To detach a checkpoint, you can still use the
2326 `detach checkpoint' command, which was an alias for the `detach
2329 * New native configurations
2331 x86/x86_64 Darwin i[34567]86-*-darwin*
2333 x86_64 MinGW x86_64-*-mingw*
2337 Lattice Mico32 lm32-*
2338 x86 DICOS i[34567]86-*-dicos*
2339 x86_64 DICOS x86_64-*-dicos*
2342 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2343 (mingw32ce) debugging.
2349 These commands were actually not implemented on any target.
2351 *** Changes in GDB 6.8
2353 * New native configurations
2355 NetBSD/hppa hppa*-*netbsd*
2356 Xtensa GNU/Linux xtensa*-*-linux*
2360 NetBSD/hppa hppa*-*-netbsd*
2361 Xtensa GNU/Lunux xtensa*-*-linux*
2363 * Change in command line behavior -- corefiles vs. process ids.
2365 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2366 attaching to process NUMBER fails, GDB no longer attempts to open a
2367 core file named NUMBER. Attaching to a program using the -c option
2368 is no longer supported. Instead, use the '-p' or '--pid' options.
2370 * GDB can now be built as a native debugger for debugging Windows x86
2371 (mingw32) Portable Executable (PE) programs.
2373 * Pending breakpoints no longer change their number when their address
2376 * GDB now supports breakpoints with multiple locations,
2377 including breakpoints on C++ constructors, inside C++ templates,
2378 and in inlined functions.
2380 * GDB's ability to debug optimized code has been improved. GDB more
2381 accurately identifies function bodies and lexical blocks that occupy
2382 more than one contiguous range of addresses.
2384 * Target descriptions can now describe registers for PowerPC.
2386 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2387 registers on PowerPC targets.
2389 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2390 targets even when the libthread_db library is not available.
2392 * The GDB remote stub, gdbserver, now supports the new file transfer
2393 commands (remote put, remote get, and remote delete).
2395 * The GDB remote stub, gdbserver, now supports run and attach in
2396 extended-remote mode.
2398 * hppa*64*-*-hpux11* target broken
2399 The debugger is unable to start a program and fails with the following
2400 error: "Error trying to get information about dynamic linker".
2401 The gdb-6.7 release is also affected.
2403 * GDB now supports the --enable-targets= configure option to allow
2404 building a single GDB executable that supports multiple remote
2405 target architectures.
2407 * GDB now supports debugging C and C++ programs which use the
2408 Decimal Floating Point extension. In addition, the PowerPC target
2409 now has a set of pseudo-registers to inspect decimal float values
2410 stored in two consecutive float registers.
2412 * The -break-insert MI command can optionally create pending
2415 * Improved support for debugging Ada
2416 Many improvements to the Ada language support have been made. These
2418 - Better support for Ada2005 interface types
2419 - Improved handling of arrays and slices in general
2420 - Better support for Taft-amendment types
2421 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2423 - Improved command completion in Ada
2426 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2431 set print frame-arguments (all|scalars|none)
2432 show print frame-arguments
2433 The value of this variable can be changed to control which argument
2434 values should be printed by the debugger when displaying a frame.
2439 Transfer files to and from a remote target, and delete remote files.
2446 Transfer files to and from a remote target, and delete remote files.
2448 * New remote packets
2455 Open, close, read, write, and delete files on the remote system.
2458 Attach to an existing process on the remote system, in extended-remote
2462 Run a new process on the remote system, in extended-remote mode.
2464 *** Changes in GDB 6.7
2466 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2467 bfd, libiberty and opcodes, as revealed by static analysis donated by
2468 Coverity, Inc. (http://scan.coverity.com).
2470 * When looking up multiply-defined global symbols, GDB will now prefer the
2471 symbol definition in the current shared library if it was built using the
2472 -Bsymbolic linker option.
2474 * When the Text User Interface (TUI) is not configured, GDB will now
2475 recognize the -tui command-line option and print a message that the TUI
2478 * The GDB remote stub, gdbserver, now has lower overhead for high
2479 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2481 * GDB for MIPS targets now autodetects whether a remote target provides
2482 32-bit or 64-bit register values.
2484 * Support for C++ member pointers has been improved.
2486 * GDB now understands XML target descriptions, which specify the
2487 target's overall architecture. GDB can read a description from
2488 a local file or over the remote serial protocol.
2490 * Vectors of single-byte data use a new integer type which is not
2491 automatically displayed as character or string data.
2493 * The /s format now works with the print command. It displays
2494 arrays of single-byte integers and pointers to single-byte integers
2497 * Target descriptions can now describe target-specific registers,
2498 for architectures which have implemented the support (currently
2499 only ARM, M68K, and MIPS).
2501 * GDB and the GDB remote stub, gdbserver, now support the XScale
2504 * The GDB remote stub, gdbserver, has been updated to support
2505 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2506 has been rewritten to use the standard GDB remote protocol.
2508 * GDB can now step into C++ functions which are called through thunks.
2510 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2512 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2513 layout. It also supports a TextSeg= and DataSeg= response when only
2514 segment base addresses (rather than offsets) are available.
2516 * The /i format now outputs any trailing branch delay slot instructions
2517 immediately following the last instruction within the count specified.
2519 * The GDB remote protocol "T" stop reply packet now supports a
2520 "library" response. Combined with the new "qXfer:libraries:read"
2521 packet, this response allows GDB to debug shared libraries on targets
2522 where the operating system manages the list of loaded libraries (e.g.
2523 Windows and SymbianOS).
2525 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2526 (DLLs) on Windows and Windows CE targets.
2528 * GDB now supports a faster verification that a .debug file matches its binary
2529 according to its build-id signature, if the signature is present.
2535 Enable or disable hardware flow control (RTS/CTS) on the serial port
2536 when debugging using remote targets.
2538 set mem inaccessible-by-default
2539 show mem inaccessible-by-default
2540 If the target supplies a memory map, for instance via the remote
2541 protocol's "qXfer:memory-map:read" packet, setting this variable
2542 prevents GDB from accessing memory outside the memory map. This
2543 is useful for targets with memory mapped registers or which react
2544 badly to accesses of unmapped address space.
2546 set breakpoint auto-hw
2547 show breakpoint auto-hw
2548 If the target supplies a memory map, for instance via the remote
2549 protocol's "qXfer:memory-map:read" packet, setting this variable
2550 lets GDB use hardware breakpoints automatically for memory regions
2551 where it can not use software breakpoints. This covers both the
2552 "break" command and internal breakpoints used for other commands
2553 including "next" and "finish".
2556 catch exception unhandled
2557 Stop the program execution when Ada exceptions are raised.
2560 Stop the program execution when an Ada assertion failed.
2564 Set an alternate system root for target files. This is a more
2565 general version of "set solib-absolute-prefix", which is now
2566 an alias to "set sysroot".
2569 Provide extended SPU facility status information. This set of
2570 commands is available only when debugging the Cell/B.E. SPU
2573 * New native configurations
2575 OpenBSD/sh sh*-*openbsd*
2578 unset tdesc filename
2580 Use the specified local file as an XML target description, and do
2581 not query the target for its built-in description.
2585 OpenBSD/sh sh*-*-openbsd*
2586 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2587 Toshiba Media Processor mep-elf
2589 * New remote packets
2592 Ignore the specified signals; pass them directly to the debugged program
2593 without stopping other threads or reporting them to GDB.
2595 qXfer:features:read:
2596 Read an XML target description from the target, which describes its
2601 Read or write contents of an spufs file on the target system. These
2602 packets are available only on the Cell/B.E. SPU architecture.
2604 qXfer:libraries:read:
2605 Report the loaded shared libraries. Combined with new "T" packet
2606 response, this packet allows GDB to debug shared libraries on
2607 targets where the operating system manages the list of loaded
2608 libraries (e.g. Windows and SymbianOS).
2612 Support for these obsolete configurations has been removed.
2620 i[34567]86-*-lynxos*
2621 i[34567]86-*-netware*
2622 i[34567]86-*-sco3.2v5*
2623 i[34567]86-*-sco3.2v4*
2625 i[34567]86-*-sysv4.2*
2628 i[34567]86-*-unixware2*
2629 i[34567]86-*-unixware*
2638 * Other removed features
2645 Various m68k-only ROM monitors.
2652 Various Renesas ROM monitors and debugging interfaces for SH and
2657 Support for a Macraigor serial interface to on-chip debugging.
2658 GDB does not directly support the newer parallel or USB
2663 A debug information format. The predecessor to DWARF 2 and
2664 DWARF 3, which are still supported.
2666 Support for the HP aCC compiler on HP-UX/PA-RISC
2668 SOM-encapsulated symbolic debugging information, automatic
2669 invocation of pxdb, and the aCC custom C++ ABI. This does not
2670 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2671 with aCC can still be debugged on an assembly level.
2673 MIPS ".pdr" sections
2675 A MIPS-specific format used to describe stack frame layout
2676 in debugging information.
2680 GDB could work with an older version of Guile to debug
2681 the interpreter and Scheme programs running in it.
2683 set mips stack-arg-size
2684 set mips saved-gpreg-size
2686 Use "set mips abi" to control parameter passing for MIPS.
2688 *** Changes in GDB 6.6
2693 Cell Broadband Engine SPU spu-elf
2695 * GDB can now be configured as a cross-debugger targeting native Windows
2696 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2697 running on a Windows system over TCP/IP to debug Windows programs.
2699 * The GDB remote stub, gdbserver, has been updated to support Windows and
2700 Cygwin debugging. Both single-threaded and multi-threaded programs are
2703 * The "set trust-readonly-sections" command works again. This command was
2704 broken in GDB 6.3, 6.4, and 6.5.
2706 * The "load" command now supports writing to flash memory, if the remote
2707 stub provides the required support.
2709 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2710 longer requires symbolic debug information (e.g. DWARF-2).
2715 unset substitute-path
2716 show substitute-path
2717 Manage a list of substitution rules that GDB uses to rewrite the name
2718 of the directories where the sources are located. This can be useful
2719 for instance when the sources were moved to a different location
2720 between compilation and debugging.
2724 Print each CLI command as it is executed. Each command is prefixed with
2725 a number of `+' symbols representing the nesting depth.
2726 The source command now has a `-v' option to enable the same feature.
2730 The ARM Demon monitor support (RDP protocol, "target rdp").
2732 Kernel Object Display, an embedded debugging feature which only worked with
2733 an obsolete version of Cisco IOS.
2735 The 'set download-write-size' and 'show download-write-size' commands.
2737 * New remote packets
2740 Tell a stub about GDB client features, and request remote target features.
2741 The first feature implemented is PacketSize, which allows the target to
2742 specify the size of packets it can handle - to minimize the number of
2743 packets required and improve performance when connected to a remote
2747 Fetch an OS auxilliary vector from the remote stub. This packet is a
2748 more efficient replacement for qPart:auxv:read.
2750 qXfer:memory-map:read:
2751 Fetch a memory map from the remote stub, including information about
2752 RAM, ROM, and flash memory devices.
2757 Erase and program a flash memory device.
2759 * Removed remote packets
2762 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2763 used it, and only gdbserver implemented it.
2765 *** Changes in GDB 6.5
2769 Renesas M32C/M16C m32c-elf
2771 Morpho Technologies ms1 ms1-elf
2775 init-if-undefined Initialize a convenience variable, but
2776 only if it doesn't already have a value.
2778 The following commands are presently only implemented for native GNU/Linux:
2780 checkpoint Save a snapshot of the program state.
2782 restart <n> Return the program state to a
2783 previously saved state.
2785 info checkpoints List currently saved checkpoints.
2787 delete-checkpoint <n> Delete a previously saved checkpoint.
2789 set|show detach-on-fork Tell gdb whether to detach from a newly
2790 forked process, or to keep debugging it.
2792 info forks List forks of the user program that
2793 are available to be debugged.
2795 fork <n> Switch to debugging one of several
2796 forks of the user program that are
2797 available to be debugged.
2799 delete-fork <n> Delete a fork from the list of forks
2800 that are available to be debugged (and
2801 kill the forked process).
2803 detach-fork <n> Delete a fork from the list of forks
2804 that are available to be debugged (and
2805 allow the process to continue).
2809 Morpho Technologies ms2 ms1-elf
2811 * Improved Windows host support
2813 GDB now builds as a cross debugger hosted on i686-mingw32, including
2814 native console support, and remote communications using either
2815 network sockets or serial ports.
2817 * Improved Modula-2 language support
2819 GDB can now print most types in the Modula-2 syntax. This includes:
2820 basic types, set types, record types, enumerated types, range types,
2821 pointer types and ARRAY types. Procedure var parameters are correctly
2822 printed and hexadecimal addresses and character constants are also
2823 written in the Modula-2 syntax. Best results can be obtained by using
2824 GNU Modula-2 together with the -gdwarf-2 command line option.
2828 The ARM rdi-share module.
2830 The Netware NLM debug server.
2832 *** Changes in GDB 6.4
2834 * New native configurations
2836 OpenBSD/arm arm*-*-openbsd*
2837 OpenBSD/mips64 mips64-*-openbsd*
2841 Morpho Technologies ms1 ms1-elf
2843 * New command line options
2845 --batch-silent As for --batch, but totally silent.
2846 --return-child-result The debugger will exist with the same value
2847 the child (debugged) program exited with.
2848 --eval-command COMMAND, -ex COMMAND
2849 Execute a single GDB CLI command. This may be
2850 specified multiple times and in conjunction
2851 with the --command (-x) option.
2853 * Deprecated commands removed
2855 The following commands, that were deprecated in 2000, have been
2859 set|show arm disassembly-flavor set|show arm disassembler
2860 othernames set arm disassembler
2861 set|show remotedebug set|show debug remote
2862 set|show archdebug set|show debug arch
2863 set|show eventdebug set|show debug event
2866 * New BSD user-level threads support
2868 It is now possible to debug programs using the user-level threads
2869 library on OpenBSD and FreeBSD. Currently supported (target)
2872 FreeBSD/amd64 x86_64-*-freebsd*
2873 FreeBSD/i386 i386-*-freebsd*
2874 OpenBSD/i386 i386-*-openbsd*
2876 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2877 are not yet supported.
2879 * New support for Matsushita MN10300 w/sim added
2880 (Work in progress). mn10300-elf.
2882 * REMOVED configurations and files
2884 VxWorks and the XDR protocol *-*-vxworks
2885 Motorola MCORE mcore-*-*
2886 National Semiconductor NS32000 ns32k-*-*
2888 * New "set print array-indexes" command
2890 After turning this setting "on", GDB prints the index of each element
2891 when displaying arrays. The default is "off" to preserve the previous
2894 * VAX floating point support
2896 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2898 * User-defined command support
2900 In addition to using $arg0..$arg9 for argument passing, it is now possible
2901 to use $argc to determine now many arguments have been passed. See the
2902 section on user-defined commands in the user manual for more information.
2904 *** Changes in GDB 6.3:
2906 * New command line option
2908 GDB now accepts -l followed by a number to set the timeout for remote
2911 * GDB works with GCC -feliminate-dwarf2-dups
2913 GDB now supports a more compact representation of DWARF-2 debug
2914 information using DW_FORM_ref_addr references. These are produced
2915 by GCC with the option -feliminate-dwarf2-dups and also by some
2916 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2917 to use -feliminate-dwarf2-dups.
2919 * Internationalization
2921 When supported by the host system, GDB will be built with
2922 internationalization (libintl). The task of marking up the sources is
2923 continued, we're looking forward to our first translation.
2927 Initial support for debugging programs compiled with the GNAT
2928 implementation of the Ada programming language has been integrated
2929 into GDB. In this release, support is limited to expression evaluation.
2931 * New native configurations
2933 GNU/Linux/m32r m32r-*-linux-gnu
2937 GDB's remote protocol now includes support for the 'p' packet. This
2938 packet is used to fetch individual registers from a remote inferior.
2940 * END-OF-LIFE registers[] compatibility module
2942 GDB's internal register infrastructure has been completely rewritten.
2943 The new infrastructure making possible the implementation of key new
2944 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2947 GDB 6.3 will be the last release to include the the registers[]
2948 compatibility module that allowed out-of-date configurations to
2949 continue to work. This change directly impacts the following
2959 powerpc bdm protocol
2961 Unless there is activity to revive these configurations, they will be
2962 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2964 * OBSOLETE configurations and files
2966 Configurations that have been declared obsolete in this release have
2967 been commented out. Unless there is activity to revive these
2968 configurations, the next release of GDB will have their sources
2969 permanently REMOVED.
2978 *** Changes in GDB 6.2.1:
2980 * MIPS `break main; run' gave an heuristic-fence-post warning
2982 When attempting to run even a simple program, a warning about
2983 heuristic-fence-post being hit would be reported. This problem has
2986 * MIPS IRIX 'long double' crashed GDB
2988 When examining a long double variable, GDB would get a segmentation
2989 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2990 IRIX long double values).
2994 A bug in the VAX stack code was causing problems with the "next"
2995 command. This problem has been fixed.
2997 *** Changes in GDB 6.2:
2999 * Fix for ``many threads''
3001 On GNU/Linux systems that use the NPTL threads library, a program
3002 rapidly creating and deleting threads would confuse GDB leading to the
3005 ptrace: No such process.
3006 thread_db_get_info: cannot get thread info: generic error
3008 This problem has been fixed.
3010 * "-async" and "-noasync" options removed.
3012 Support for the broken "-noasync" option has been removed (it caused
3015 * New ``start'' command.
3017 This command runs the program until the begining of the main procedure.
3019 * New BSD Kernel Data Access Library (libkvm) interface
3021 Using ``target kvm'' it is now possible to debug kernel core dumps and
3022 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3023 platforms. Currently supported (native-only) configurations are:
3025 FreeBSD/amd64 x86_64-*-freebsd*
3026 FreeBSD/i386 i?86-*-freebsd*
3027 NetBSD/i386 i?86-*-netbsd*
3028 NetBSD/m68k m68*-*-netbsd*
3029 NetBSD/sparc sparc-*-netbsd*
3030 OpenBSD/amd64 x86_64-*-openbsd*
3031 OpenBSD/i386 i?86-*-openbsd*
3032 OpenBSD/m68k m68*-openbsd*
3033 OpenBSD/sparc sparc-*-openbsd*
3035 * Signal trampoline code overhauled
3037 Many generic problems with GDB's signal handling code have been fixed.
3038 These include: backtraces through non-contiguous stacks; recognition
3039 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3040 call; backtrace through a signal trampoline; step into and out of
3041 signal handlers; and single-stepping in the signal trampoline.
3043 Please note that kernel bugs are a limiting factor here. These
3044 features have been shown to work on an s390 GNU/Linux system that
3045 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3047 * Cygwin support for DWARF 2 added.
3049 * New native configurations
3051 GNU/Linux/hppa hppa*-*-linux*
3052 OpenBSD/hppa hppa*-*-openbsd*
3053 OpenBSD/m68k m68*-*-openbsd*
3054 OpenBSD/m88k m88*-*-openbsd*
3055 OpenBSD/powerpc powerpc-*-openbsd*
3056 NetBSD/vax vax-*-netbsd*
3057 OpenBSD/vax vax-*-openbsd*
3059 * END-OF-LIFE frame compatibility module
3061 GDB's internal frame infrastructure has been completely rewritten.
3062 The new infrastructure making it possible to support key new features
3063 including DWARF 2 Call Frame Information. To aid in the task of
3064 migrating old configurations to this new infrastructure, a
3065 compatibility module, that allowed old configurations to continue to
3066 work, was also included.
3068 GDB 6.2 will be the last release to include this frame compatibility
3069 module. This change directly impacts the following configurations:
3079 Unless there is activity to revive these configurations, they will be
3080 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3082 * REMOVED configurations and files
3084 Sun 3, running SunOS 3 m68*-*-sunos3*
3085 Sun 3, running SunOS 4 m68*-*-sunos4*
3086 Sun 2, running SunOS 3 m68000-*-sunos3*
3087 Sun 2, running SunOS 4 m68000-*-sunos4*
3088 Motorola 680x0 running LynxOS m68*-*-lynxos*
3089 AT&T 3b1/Unix pc m68*-att-*
3090 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3091 decstation mips-dec-* mips-little-*
3092 riscos mips-*-riscos* mips-*-sysv*
3093 sonymips mips-sony-*
3094 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3096 *** Changes in GDB 6.1.1:
3098 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3100 The TUI (Text-mode User Interface) is now built as part of a default
3101 GDB configuration. It is enabled by either selecting the TUI with the
3102 command line option "-i=tui" or by running the separate "gdbtui"
3103 program. For more information on the TUI, see the manual "Debugging
3106 * Pending breakpoint support (also included in GDB 6.1)
3108 Support has been added to allow you to specify breakpoints in shared
3109 libraries that have not yet been loaded. If a breakpoint location
3110 cannot be found, and the "breakpoint pending" option is set to auto,
3111 GDB queries you if you wish to make the breakpoint pending on a future
3112 shared-library load. If and when GDB resolves the breakpoint symbol,
3113 the pending breakpoint is removed as one or more regular breakpoints
3116 Pending breakpoints are very useful for GCJ Java debugging.
3118 * Fixed ISO-C build problems
3120 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3121 non ISO-C code that stopped them being built using a more strict ISO-C
3122 compiler (e.g., IBM's C compiler).
3124 * Fixed build problem on IRIX 5
3126 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3127 wasn't able to compile compile on an IRIX 5 system.
3129 * Added execute permission to gdb/gdbserver/configure
3131 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3132 permission. This bug would cause configure to fail on a number of
3133 systems (Solaris, IRIX). Ref: server/519.
3135 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3137 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3138 has been updated to use constant array sizes.
3140 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3142 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3143 its generated DWARF Call Frame Info. This encoding was causing GDB to
3144 panic, that panic has been fixed. Ref: gdb/1628.
3146 * Fixed a problem when examining parameters in shared library code.
3148 When examining parameters in optimized shared library code generated
3149 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3150 not available''. GDB now correctly displays the variable's value.
3152 *** Changes in GDB 6.1:
3154 * Removed --with-mmalloc
3156 Support for the mmalloc memory manager has been removed, as it
3157 conflicted with the internal gdb byte cache.
3159 * Changes in AMD64 configurations
3161 The AMD64 target now includes the %cs and %ss registers. As a result
3162 the AMD64 remote protocol has changed; this affects the floating-point
3163 and SSE registers. If you rely on those registers for your debugging,
3164 you should upgrade gdbserver on the remote side.
3166 * Revised SPARC target
3168 The SPARC target has been completely revised, incorporating the
3169 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3170 support for LynxOS and SunOS 4 has been dropped. Calling functions
3171 from within GDB on operating systems with a non-executable stack
3172 (Solaris, OpenBSD) now works.
3176 GDB has a new C++ demangler which does a better job on the mangled
3177 names generated by current versions of g++. It also runs faster, so
3178 with this and other changes gdb should now start faster on large C++
3181 * DWARF 2 Location Expressions
3183 GDB support for location expressions has been extended to support function
3184 arguments and frame bases. Older versions of GDB could crash when they
3187 * C++ nested types and namespaces
3189 GDB's support for nested types and namespaces in C++ has been
3190 improved, especially if you use the DWARF 2 debugging format. (This
3191 is the default for recent versions of GCC on most platforms.)
3192 Specifically, if you have a class "Inner" defined within a class or
3193 namespace "Outer", then GDB realizes that the class's name is
3194 "Outer::Inner", not simply "Inner". This should greatly reduce the
3195 frequency of complaints about not finding RTTI symbols. In addition,
3196 if you are stopped at inside of a function defined within a namespace,
3197 GDB modifies its name lookup accordingly.
3199 * New native configurations
3201 NetBSD/amd64 x86_64-*-netbsd*
3202 OpenBSD/amd64 x86_64-*-openbsd*
3203 OpenBSD/alpha alpha*-*-openbsd*
3204 OpenBSD/sparc sparc-*-openbsd*
3205 OpenBSD/sparc64 sparc64-*-openbsd*
3207 * New debugging protocols
3209 M32R with SDI protocol m32r-*-elf*
3211 * "set prompt-escape-char" command deleted.
3213 The command "set prompt-escape-char" has been deleted. This command,
3214 and its very obscure effet on GDB's prompt, was never documented,
3215 tested, nor mentioned in the NEWS file.
3217 * OBSOLETE configurations and files
3219 Configurations that have been declared obsolete in this release have
3220 been commented out. Unless there is activity to revive these
3221 configurations, the next release of GDB will have their sources
3222 permanently REMOVED.
3224 Sun 3, running SunOS 3 m68*-*-sunos3*
3225 Sun 3, running SunOS 4 m68*-*-sunos4*
3226 Sun 2, running SunOS 3 m68000-*-sunos3*
3227 Sun 2, running SunOS 4 m68000-*-sunos4*
3228 Motorola 680x0 running LynxOS m68*-*-lynxos*
3229 AT&T 3b1/Unix pc m68*-att-*
3230 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3231 decstation mips-dec-* mips-little-*
3232 riscos mips-*-riscos* mips-*-sysv*
3233 sonymips mips-sony-*
3234 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3236 * REMOVED configurations and files
3238 SGI Irix-4.x mips-sgi-irix4 or iris4
3239 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3240 Z8000 simulator z8k-zilog-none or z8ksim
3241 Matsushita MN10200 w/simulator mn10200-*-*
3242 H8/500 simulator h8500-hitachi-hms or h8500hms
3243 HP/PA running BSD hppa*-*-bsd*
3244 HP/PA running OSF/1 hppa*-*-osf*
3245 HP/PA Pro target hppa*-*-pro*
3246 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3247 386BSD i[3456]86-*-bsd*
3248 Sequent family i[3456]86-sequent-sysv4*
3249 i[3456]86-sequent-sysv*
3250 i[3456]86-sequent-bsd*
3251 SPARC running LynxOS sparc-*-lynxos*
3252 SPARC running SunOS 4 sparc-*-sunos4*
3253 Tsqware Sparclet sparclet-*-*
3254 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3256 *** Changes in GDB 6.0:
3260 Support for debugging the Objective-C programming language has been
3261 integrated into GDB.
3263 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3265 DWARF 2's Call Frame Information makes available compiler generated
3266 information that more exactly describes the program's run-time stack.
3267 By using this information, GDB is able to provide more robust stack
3270 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3271 have been updated to use a new backtrace mechanism which includes
3272 DWARF 2 CFI support.
3276 GDB's remote protocol has been extended to include support for hosted
3277 file I/O (where the remote target uses GDB's file system). See GDB's
3278 remote protocol documentation for details.
3280 * All targets using the new architecture framework.
3282 All of GDB's targets have been updated to use the new internal
3283 architecture framework. The way is now open for future GDB releases
3284 to include cross-architecture native debugging support (i386 on amd64,
3287 * GNU/Linux's Thread Local Storage (TLS)
3289 GDB now includes support for for the GNU/Linux implementation of
3290 per-thread variables.
3292 * GNU/Linux's Native POSIX Thread Library (NPTL)
3294 GDB's thread code has been updated to work with either the new
3295 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3297 * Separate debug info.
3299 GDB, in conjunction with BINUTILS, now supports a mechanism for
3300 automatically loading debug information from a separate file. Instead
3301 of shipping full debug and non-debug versions of system libraries,
3302 system integrators can now instead ship just the stripped libraries
3303 and optional debug files.
3305 * DWARF 2 Location Expressions
3307 DWARF 2 Location Expressions allow the compiler to more completely
3308 describe the location of variables (even in optimized code) to the
3311 GDB now includes preliminary support for location expressions (support
3312 for DW_OP_piece is still missing).
3316 A number of long standing bugs that caused GDB to die while starting a
3317 Java application have been fixed. GDB's Java support is now
3318 considered "useable".
3320 * GNU/Linux support for fork, vfork, and exec.
3322 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3323 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3326 * GDB supports logging output to a file
3328 There are two new commands, "set logging" and "show logging", which can be
3329 used to capture GDB's output to a file.
3331 * The meaning of "detach" has changed for gdbserver
3333 The "detach" command will now resume the application, as documented. To
3334 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3337 * d10v, m68hc11 `regs' command deprecated
3339 The `info registers' command has been updated so that it displays the
3340 registers using a format identical to the old `regs' command.
3344 A new command, "maint set profile on/off", has been added. This command can
3345 be used to enable or disable profiling while running GDB, to profile a
3346 session or a set of commands. In addition there is a new configure switch,
3347 "--enable-profiling", which will cause GDB to be compiled with profiling
3348 data, for more informative profiling results.
3350 * Default MI syntax changed to "mi2".
3352 The default MI (machine interface) syntax, enabled by the command line
3353 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3354 "mi1", can be enabled by specifying the option "-i=mi1".
3356 Support for the original "mi0" syntax (included in GDB 5.0) has been
3359 Fix for gdb/192: removed extraneous space when displaying frame level.
3360 Fix for gdb/672: update changelist is now output in mi list format.
3361 Fix for gdb/702: a -var-assign that updates the value now shows up
3362 in a subsequent -var-update.
3364 * New native configurations.
3366 FreeBSD/amd64 x86_64-*-freebsd*
3368 * Multi-arched targets.
3370 HP/PA HPUX11 hppa*-*-hpux*
3371 Renesas M32R/D w/simulator m32r-*-elf*
3373 * OBSOLETE configurations and files
3375 Configurations that have been declared obsolete in this release have
3376 been commented out. Unless there is activity to revive these
3377 configurations, the next release of GDB will have their sources
3378 permanently REMOVED.
3380 Z8000 simulator z8k-zilog-none or z8ksim
3381 Matsushita MN10200 w/simulator mn10200-*-*
3382 H8/500 simulator h8500-hitachi-hms or h8500hms
3383 HP/PA running BSD hppa*-*-bsd*
3384 HP/PA running OSF/1 hppa*-*-osf*
3385 HP/PA Pro target hppa*-*-pro*
3386 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3387 Sequent family i[3456]86-sequent-sysv4*
3388 i[3456]86-sequent-sysv*
3389 i[3456]86-sequent-bsd*
3390 Tsqware Sparclet sparclet-*-*
3391 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3393 * REMOVED configurations and files
3396 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3397 IBM AIX PS/2 i[3456]86-*-aix
3398 i386 running Mach 3.0 i[3456]86-*-mach3*
3399 i386 running Mach i[3456]86-*-mach*
3400 i386 running OSF/1 i[3456]86-*osf1mk*
3401 HP/Apollo 68k Family m68*-apollo*-sysv*,
3403 m68*-hp-bsd*, m68*-hp-hpux*
3404 Argonaut Risc Chip (ARC) arc-*-*
3405 Mitsubishi D30V d30v-*-*
3406 Fujitsu FR30 fr30-*-elf*
3407 OS/9000 i[34]86-*-os9k
3408 I960 with MON960 i960-*-coff
3410 * MIPS $fp behavior changed
3412 The convenience variable $fp, for the MIPS, now consistently returns
3413 the address of the current frame's base. Previously, depending on the
3414 context, $fp could refer to either $sp or the current frame's base
3415 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3416 The GNU Source-Level Debugger''.
3418 *** Changes in GDB 5.3:
3420 * GNU/Linux shared library multi-threaded performance improved.
3422 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3423 `/proc', in preference to `ptrace' for memory reads. This may result
3424 in an improvement in the start-up time of multi-threaded, shared
3425 library applications when run under GDB. One GDB user writes: ``loads
3426 shared libs like mad''.
3428 * ``gdbserver'' now supports multi-threaded applications on some targets
3430 Support for debugging multi-threaded applications which use
3431 the GNU/Linux LinuxThreads package has been added for
3432 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3433 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3435 * GDB now supports C/C++ preprocessor macros.
3437 GDB now expands preprocessor macro invocations in C/C++ expressions,
3438 and provides various commands for showing macro definitions and how
3441 The new command `macro expand EXPRESSION' expands any macro
3442 invocations in expression, and shows the result.
3444 The new command `show macro MACRO-NAME' shows the definition of the
3445 macro named MACRO-NAME, and where it was defined.
3447 Most compilers don't include information about macros in the debugging
3448 information by default. In GCC 3.1, for example, you need to compile
3449 your program with the options `-gdwarf-2 -g3'. If the macro
3450 information is present in the executable, GDB will read it.
3452 * Multi-arched targets.
3454 DEC Alpha (partial) alpha*-*-*
3455 DEC VAX (partial) vax-*-*
3457 National Semiconductor NS32000 (partial) ns32k-*-*
3458 Motorola 68000 (partial) m68k-*-*
3459 Motorola MCORE mcore-*-*
3463 Fujitsu FRV architecture added by Red Hat frv*-*-*
3466 * New native configurations
3468 Alpha NetBSD alpha*-*-netbsd*
3469 SH NetBSD sh*-*-netbsdelf*
3470 MIPS NetBSD mips*-*-netbsd*
3471 UltraSPARC NetBSD sparc64-*-netbsd*
3473 * OBSOLETE configurations and files
3475 Configurations that have been declared obsolete in this release have
3476 been commented out. Unless there is activity to revive these
3477 configurations, the next release of GDB will have their sources
3478 permanently REMOVED.
3480 Mitsubishi D30V d30v-*-*
3481 OS/9000 i[34]86-*-os9k
3482 IBM AIX PS/2 i[3456]86-*-aix
3483 Fujitsu FR30 fr30-*-elf*
3484 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3485 Argonaut Risc Chip (ARC) arc-*-*
3486 i386 running Mach 3.0 i[3456]86-*-mach3*
3487 i386 running Mach i[3456]86-*-mach*
3488 i386 running OSF/1 i[3456]86-*osf1mk*
3489 HP/Apollo 68k Family m68*-apollo*-sysv*,
3491 m68*-hp-bsd*, m68*-hp-hpux*
3492 I960 with MON960 i960-*-coff
3494 * OBSOLETE languages
3496 CHILL, a Pascal like language used by telecommunications companies.
3498 * REMOVED configurations and files
3500 AMD 29k family via UDI a29k-amd-udi, udi29k
3501 A29K VxWorks a29k-*-vxworks
3502 AMD 29000 embedded, using EBMON a29k-none-none
3503 AMD 29000 embedded with COFF a29k-none-coff
3504 AMD 29000 embedded with a.out a29k-none-aout
3506 testsuite/gdb.hp/gdb.threads-hp/ directory
3508 * New command "set max-user-call-depth <nnn>"
3510 This command allows the user to limit the call depth of user-defined
3511 commands. The default is 1024.
3513 * Changes in FreeBSD/i386 native debugging.
3515 Support for the "generate-core-file" has been added.
3517 * New commands "dump", "append", and "restore".
3519 These commands allow data to be copied from target memory
3520 to a bfd-format or binary file (dump and append), and back
3521 from a file into memory (restore).
3523 * Improved "next/step" support on multi-processor Alpha Tru64.
3525 The previous single-step mechanism could cause unpredictable problems,
3526 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3527 of a software single-step mechanism prevents this.
3529 *** Changes in GDB 5.2.1:
3537 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3538 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3539 Fix, by Joel Brobecker imported from mainline.
3541 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3542 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3543 Fix, by Fred Fish, imported from mainline.
3545 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3546 Surprisingly enough, it works now.
3547 By Michal Ludvig, imported from mainline.
3549 i386 hardware watchpoint support:
3550 avoid misses on second run for some targets.
3551 By Pierre Muller, imported from mainline.
3553 *** Changes in GDB 5.2:
3555 * New command "set trust-readonly-sections on[off]".
3557 This command is a hint that tells gdb that read-only sections
3558 really are read-only (ie. that their contents will not change).
3559 In this mode, gdb will go to the object file rather than the
3560 target to read memory from read-only sections (such as ".text").
3561 This can be a significant performance improvement on some
3562 (notably embedded) targets.
3564 * New command "generate-core-file" (or "gcore").
3566 This new gdb command allows the user to drop a core file of the child
3567 process state at any time. So far it's been implemented only for
3568 GNU/Linux and Solaris, but should be relatively easily ported to other
3569 hosts. Argument is core file name (defaults to core.<pid>).
3571 * New command line option
3573 GDB now accepts --pid or -p followed by a process id.
3575 * Change in command line behavior -- corefiles vs. process ids.
3577 There is a subtle behavior in the way in which GDB handles
3578 command line arguments. The first non-flag argument is always
3579 a program to debug, but the second non-flag argument may either
3580 be a corefile or a process id. Previously, GDB would attempt to
3581 open the second argument as a corefile, and if that failed, would
3582 issue a superfluous error message and then attempt to attach it as
3583 a process. Now, if the second argument begins with a non-digit,
3584 it will be treated as a corefile. If it begins with a digit,
3585 GDB will attempt to attach it as a process, and if no such process
3586 is found, will then attempt to open it as a corefile.
3588 * Changes in ARM configurations.
3590 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3591 configuration is fully multi-arch.
3593 * New native configurations
3595 ARM NetBSD arm*-*-netbsd*
3596 x86 OpenBSD i[3456]86-*-openbsd*
3597 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3598 Sparc64 running FreeBSD sparc64-*-freebsd*
3602 Sanyo XStormy16 xstormy16-elf
3604 * OBSOLETE configurations and files
3606 Configurations that have been declared obsolete in this release have
3607 been commented out. Unless there is activity to revive these
3608 configurations, the next release of GDB will have their sources
3609 permanently REMOVED.
3611 AMD 29k family via UDI a29k-amd-udi, udi29k
3612 A29K VxWorks a29k-*-vxworks
3613 AMD 29000 embedded, using EBMON a29k-none-none
3614 AMD 29000 embedded with COFF a29k-none-coff
3615 AMD 29000 embedded with a.out a29k-none-aout
3617 testsuite/gdb.hp/gdb.threads-hp/ directory
3619 * REMOVED configurations and files
3621 TI TMS320C80 tic80-*-*
3623 PowerPC Solaris powerpcle-*-solaris*
3624 PowerPC Windows NT powerpcle-*-cygwin32
3625 PowerPC Netware powerpc-*-netware*
3626 Harris/CXUX m88k m88*-harris-cxux*
3627 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3628 ns32k-utek-sysv* ns32k-utek-*
3629 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3630 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3631 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3632 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3633 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3635 * Changes to command line processing
3637 The new `--args' feature can be used to specify command-line arguments
3638 for the inferior from gdb's command line.
3640 * Changes to key bindings
3642 There is a new `operate-and-get-next' function bound to `C-o'.
3644 *** Changes in GDB 5.1.1
3646 Fix compile problem on DJGPP.
3648 Fix a problem with floating-point registers on the i386 being
3651 Fix to stop GDB crashing on .debug_str debug info.
3653 Numerous documentation fixes.
3655 Numerous testsuite fixes.
3657 *** Changes in GDB 5.1:
3659 * New native configurations
3661 Alpha FreeBSD alpha*-*-freebsd*
3662 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3663 MIPS GNU/Linux mips*-*-linux*
3664 MIPS SGI Irix 6.x mips*-sgi-irix6*
3665 ia64 AIX ia64-*-aix*
3666 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3670 Motorola 68HC11 and 68HC12 m68hc11-elf
3672 UltraSparc running GNU/Linux sparc64-*-linux*
3674 * OBSOLETE configurations and files
3676 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3677 Harris/CXUX m88k m88*-harris-cxux*
3678 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3679 ns32k-utek-sysv* ns32k-utek-*
3680 TI TMS320C80 tic80-*-*
3682 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3683 PowerPC Solaris powerpcle-*-solaris*
3684 PowerPC Windows NT powerpcle-*-cygwin32
3685 PowerPC Netware powerpc-*-netware*
3686 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3687 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3688 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3689 Apple Macintosh (MPW) host N/A
3691 stuff.c (Program to stuff files into a specially prepared space in kdb)
3692 kdb-start.c (Main loop for the standalone kernel debugger)
3694 Configurations that have been declared obsolete in this release have
3695 been commented out. Unless there is activity to revive these
3696 configurations, the next release of GDB will have their sources
3697 permanently REMOVED.
3699 * REMOVED configurations and files
3701 Altos 3068 m68*-altos-*
3702 Convex c1-*-*, c2-*-*
3704 ARM RISCix arm-*-* (as host)
3708 * GDB has been converted to ISO C.
3710 GDB's source code has been converted to ISO C. In particular, the
3711 sources are fully protoized, and rely on standard headers being
3716 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3718 * The MI enabled by default.
3720 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3721 revised and enabled by default. Packages which use GDB as a debugging
3722 engine behind a UI or another front end are encouraged to switch to
3723 using the GDB/MI interface, instead of the old annotations interface
3724 which is now deprecated.
3726 * Support for debugging Pascal programs.
3728 GDB now includes support for debugging Pascal programs. The following
3729 main features are supported:
3731 - Pascal-specific data types such as sets;
3733 - automatic recognition of Pascal sources based on file-name
3736 - Pascal-style display of data types, variables, and functions;
3738 - a Pascal expression parser.
3740 However, some important features are not yet supported.
3742 - Pascal string operations are not supported at all;
3744 - there are some problems with boolean types;
3746 - Pascal type hexadecimal constants are not supported
3747 because they conflict with the internal variables format;
3749 - support for Pascal objects and classes is not full yet;
3751 - unlike Pascal, GDB is case-sensitive for symbol names.
3753 * Changes in completion.
3755 Commands such as `shell', `run' and `set args', which pass arguments
3756 to inferior programs, now complete on file names, similar to what
3757 users expect at the shell prompt.
3759 Commands which accept locations, such as `disassemble', `print',
3760 `breakpoint', `until', etc. now complete on filenames as well as
3761 program symbols. Thus, if you type "break foob TAB", and the source
3762 files linked into the programs include `foobar.c', that file name will
3763 be one of the candidates for completion. However, file names are not
3764 considered for completion after you typed a colon that delimits a file
3765 name from a name of a function in that file, as in "break foo.c:bar".
3767 `set demangle-style' completes on available demangling styles.
3769 * New platform-independent commands:
3771 It is now possible to define a post-hook for a command as well as a
3772 hook that runs before the command. For more details, see the
3773 documentation of `hookpost' in the GDB manual.
3775 * Changes in GNU/Linux native debugging.
3777 Support for debugging multi-threaded programs has been completely
3778 revised for all platforms except m68k and sparc. You can now debug as
3779 many threads as your system allows you to have.
3781 Attach/detach is supported for multi-threaded programs.
3783 Support for SSE registers was added for x86. This doesn't work for
3784 multi-threaded programs though.
3786 * Changes in MIPS configurations.
3788 Multi-arch support is enabled for all MIPS configurations.
3790 GDB can now be built as native debugger on SGI Irix 6.x systems for
3791 debugging n32 executables. (Debugging 64-bit executables is not yet
3794 * Unified support for hardware watchpoints in all x86 configurations.
3796 Most (if not all) native x86 configurations support hardware-assisted
3797 breakpoints and watchpoints in a unified manner. This support
3798 implements debug register sharing between watchpoints, which allows to
3799 put a virtually infinite number of watchpoints on the same address,
3800 and also supports watching regions up to 16 bytes with several debug
3803 The new maintenance command `maintenance show-debug-regs' toggles
3804 debugging print-outs in functions that insert, remove, and test
3805 watchpoints and hardware breakpoints.
3807 * Changes in the DJGPP native configuration.
3809 New command ``info dos sysinfo'' displays assorted information about
3810 the CPU, OS, memory, and DPMI server.
3812 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3813 display information about segment descriptors stored in GDT, LDT, and
3816 New commands ``info dos pde'' and ``info dos pte'' display entries
3817 from Page Directory and Page Tables (for now works with CWSDPMI only).
3818 New command ``info dos address-pte'' displays the Page Table entry for
3819 a given linear address.
3821 GDB can now pass command lines longer than 126 characters to the
3822 program being debugged (requires an update to the libdbg.a library
3823 which is part of the DJGPP development kit).
3825 DWARF2 debug info is now supported.
3827 It is now possible to `step' and `next' through calls to `longjmp'.
3829 * Changes in documentation.
3831 All GDB documentation was converted to GFDL, the GNU Free
3832 Documentation License.
3834 Tracepoints-related commands are now fully documented in the GDB
3837 TUI, the Text-mode User Interface, is now documented in the manual.
3839 Tracepoints-related commands are now fully documented in the GDB
3842 The "GDB Internals" manual now has an index. It also includes
3843 documentation of `ui_out' functions, GDB coding standards, x86
3844 hardware watchpoints, and memory region attributes.
3846 * GDB's version number moved to ``version.in''
3848 The Makefile variable VERSION has been replaced by the file
3849 ``version.in''. People creating GDB distributions should update the
3850 contents of this file.
3854 GUD support is now a standard part of the EMACS distribution.
3856 *** Changes in GDB 5.0:
3858 * Improved support for debugging FP programs on x86 targets
3860 Unified and much-improved support for debugging floating-point
3861 programs on all x86 targets. In particular, ``info float'' now
3862 displays the FP registers in the same format on all x86 targets, with
3863 greater level of detail.
3865 * Improvements and bugfixes in hardware-assisted watchpoints
3867 It is now possible to watch array elements, struct members, and
3868 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3869 on x86 targets no longer erroneously trigger when the address is
3872 * Improvements in the native DJGPP version of GDB
3874 The distribution now includes all the scripts and auxiliary files
3875 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3876 machines ``out of the box''.
3878 The DJGPP version can now debug programs that use signals. It is
3879 possible to catch signals that happened in the debuggee, deliver
3880 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3881 would kill the program being debugged.) Programs that hook hardware
3882 interrupts (keyboard, timer, etc.) can also be debugged.
3884 It is now possible to debug DJGPP programs that redirect their
3885 standard handles or switch them to raw (as opposed to cooked) mode, or
3886 even close them. The command ``run < foo > bar'' works as expected,
3887 and ``info terminal'' reports useful information about the debuggee's
3888 terminal, including raw/cooked mode, redirection, etc.
3890 The DJGPP version now uses termios functions for console I/O, which
3891 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3894 DOS-style file names with drive letters are now fully supported by
3897 It is now possible to debug DJGPP programs that switch their working
3898 directory. It is also possible to rerun the debuggee any number of
3899 times without restarting GDB; thus, you can use the same setup,
3900 breakpoints, etc. for many debugging sessions.
3902 * New native configurations
3904 ARM GNU/Linux arm*-*-linux*
3905 PowerPC GNU/Linux powerpc-*-linux*
3909 Motorola MCore mcore-*-*
3910 x86 VxWorks i[3456]86-*-vxworks*
3911 PowerPC VxWorks powerpc-*-vxworks*
3912 TI TMS320C80 tic80-*-*
3914 * OBSOLETE configurations
3916 Altos 3068 m68*-altos-*
3917 Convex c1-*-*, c2-*-*
3919 ARM RISCix arm-*-* (as host)
3922 Configurations that have been declared obsolete will be commented out,
3923 but the code will be left in place. If there is no activity to revive
3924 these configurations before the next release of GDB, the sources will
3925 be permanently REMOVED.
3927 * Gould support removed
3929 Support for the Gould PowerNode and NP1 has been removed.
3931 * New features for SVR4
3933 On SVR4 native platforms (such as Solaris), if you attach to a process
3934 without first loading a symbol file, GDB will now attempt to locate and
3935 load symbols from the running process's executable file.
3937 * Many C++ enhancements
3939 C++ support has been greatly improved. Overload resolution now works properly
3940 in almost all cases. RTTI support is on the way.
3942 * Remote targets can connect to a sub-program
3944 A popen(3) style serial-device has been added. This device starts a
3945 sub-process (such as a stand-alone simulator) and then communicates
3946 with that. The sub-program to run is specified using the syntax
3947 ``|<program> <args>'' vis:
3949 (gdb) set remotedebug 1
3950 (gdb) target extended-remote |mn10300-elf-sim program-args
3952 * MIPS 64 remote protocol
3954 A long standing bug in the mips64 remote protocol where by GDB
3955 expected certain 32 bit registers (ex SR) to be transfered as 32
3956 instead of 64 bits has been fixed.
3958 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3959 added to provide backward compatibility with older versions of GDB.
3961 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3963 The command ``set remotebinarydownload'' command has been replaced by
3964 ``set remote X-packet''. Other commands in ``set remote'' family
3965 include ``set remote P-packet''.
3967 * Breakpoint commands accept ranges.
3969 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3970 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3971 ``tracepoint passcount'' also accepts a range of tracepoints.
3973 * ``apropos'' command added.
3975 The ``apropos'' command searches through command names and
3976 documentation strings, printing out matches, making it much easier to
3977 try to find a command that does what you are looking for.
3981 A new machine oriented interface (MI) has been added to GDB. This
3982 interface is designed for debug environments running GDB as a separate
3983 process. This is part of the long term libGDB project. See the
3984 "GDB/MI" chapter of the GDB manual for further information. It can be
3985 enabled by configuring with:
3987 .../configure --enable-gdbmi
3989 *** Changes in GDB-4.18:
3991 * New native configurations
3993 HP-UX 10.20 hppa*-*-hpux10.20
3994 HP-UX 11.x hppa*-*-hpux11.0*
3995 M68K GNU/Linux m68*-*-linux*
3999 Fujitsu FR30 fr30-*-elf*
4000 Intel StrongARM strongarm-*-*
4001 Mitsubishi D30V d30v-*-*
4003 * OBSOLETE configurations
4005 Gould PowerNode, NP1 np1-*-*, pn-*-*
4007 Configurations that have been declared obsolete will be commented out,
4008 but the code will be left in place. If there is no activity to revive
4009 these configurations before the next release of GDB, the sources will
4010 be permanently REMOVED.
4014 As a compatibility experiment, GDB's source files buildsym.h and
4015 buildsym.c have been converted to pure standard C, no longer
4016 containing any K&R compatibility code. We believe that all systems in
4017 use today either come with a standard C compiler, or have a GCC port
4018 available. If this is not true, please report the affected
4019 configuration to bug-gdb@gnu.org immediately. See the README file for
4020 information about getting a standard C compiler if you don't have one
4025 GDB now uses readline 2.2.
4027 * set extension-language
4029 You can now control the mapping between filename extensions and source
4030 languages by using the `set extension-language' command. For instance,
4031 you can ask GDB to treat .c files as C++ by saying
4032 set extension-language .c c++
4033 The command `info extensions' lists all of the recognized extensions
4034 and their associated languages.
4036 * Setting processor type for PowerPC and RS/6000
4038 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4039 you can use the `set processor' command to specify what variant of the
4040 PowerPC family you are debugging. The command
4044 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4045 following PowerPC and RS6000 variants:
4047 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4048 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4050 403GC IBM PowerPC 403GC
4051 505 Motorola PowerPC 505
4052 860 Motorola PowerPC 860 or 850
4053 601 Motorola PowerPC 601
4054 602 Motorola PowerPC 602
4055 603 Motorola/IBM PowerPC 603 or 603e
4056 604 Motorola PowerPC 604 or 604e
4057 750 Motorola/IBM PowerPC 750 or 750
4059 At the moment, this command just tells GDB what to name the
4060 special-purpose processor registers. Since almost all the affected
4061 registers are inaccessible to user-level programs, this command is
4062 only useful for remote debugging in its present form.
4066 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4067 more extensive support for HP-UX. Added features include shared
4068 library support, kernel threads and hardware watchpoints for 11.00,
4069 support for HP's ANSI C and C++ compilers, and a compatibility mode
4070 for xdb and dbx commands.
4074 HP's donation includes the new concept of catchpoints, which is a
4075 generalization of the old catch command. On HP-UX, it is now possible
4076 to catch exec, fork, and vfork, as well as library loading.
4078 This means that the existing catch command has changed; its first
4079 argument now specifies the type of catch to be set up. See the
4080 output of "help catch" for a list of catchpoint types.
4082 * Debugging across forks
4084 On HP-UX, you can choose which process to debug when a fork() happens
4089 HP has donated a curses-based terminal user interface (TUI). To get
4090 it, build with --enable-tui. Although this can be enabled for any
4091 configuration, at present it only works for native HP debugging.
4093 * GDB remote protocol additions
4095 A new protocol packet 'X' that writes binary data is now available.
4096 Default behavior is to try 'X', then drop back to 'M' if the stub
4097 fails to respond. The settable variable `remotebinarydownload'
4098 allows explicit control over the use of 'X'.
4100 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4101 full 64-bit address. The command
4103 set remoteaddresssize 32
4105 can be used to revert to the old behaviour. For existing remote stubs
4106 the change should not be noticed, as the additional address information
4109 In order to assist in debugging stubs, you may use the maintenance
4110 command `packet' to send any text string to the stub. For instance,
4112 maint packet heythere
4114 sends the packet "$heythere#<checksum>". Note that it is very easy to
4115 disrupt a debugging session by sending the wrong packet at the wrong
4118 The compare-sections command allows you to compare section data on the
4119 target to what is in the executable file without uploading or
4120 downloading, by comparing CRC checksums.
4122 * Tracing can collect general expressions
4124 You may now collect general expressions at tracepoints. This requires
4125 further additions to the target-side stub; see tracepoint.c and
4126 doc/agentexpr.texi for further details.
4128 * mask-address variable for Mips
4130 For Mips targets, you may control the zeroing of the upper 32 bits of
4131 a 64-bit address by entering `set mask-address on'. This is mainly
4132 of interest to users of embedded R4xxx and R5xxx processors.
4134 * Higher serial baud rates
4136 GDB's serial code now allows you to specify baud rates 57600, 115200,
4137 230400, and 460800 baud. (Note that your host system may not be able
4138 to achieve all of these rates.)
4142 The i960 configuration now includes an initial implementation of a
4143 builtin simulator, contributed by Jim Wilson.
4146 *** Changes in GDB-4.17:
4148 * New native configurations
4150 Alpha GNU/Linux alpha*-*-linux*
4151 Unixware 2.x i[3456]86-unixware2*
4152 Irix 6.x mips*-sgi-irix6*
4153 PowerPC GNU/Linux powerpc-*-linux*
4154 PowerPC Solaris powerpcle-*-solaris*
4155 Sparc GNU/Linux sparc-*-linux*
4156 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4160 Argonaut Risc Chip (ARC) arc-*-*
4161 Hitachi H8/300S h8300*-*-*
4162 Matsushita MN10200 w/simulator mn10200-*-*
4163 Matsushita MN10300 w/simulator mn10300-*-*
4164 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4165 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4166 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4167 Mitsubishi D10V w/simulator d10v-*-*
4168 Mitsubishi M32R/D w/simulator m32r-*-elf*
4169 Tsqware Sparclet sparclet-*-*
4170 NEC V850 w/simulator v850-*-*
4172 * New debugging protocols
4174 ARM with RDI protocol arm*-*-*
4175 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4176 DDB and LSI variants of PMON protocol mips*-*-*
4177 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4178 PowerPC with SDS protocol powerpc{,le}-*-eabi
4179 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4183 All configurations can now understand and use the DWARF 2 debugging
4184 format. The choice is automatic, if the symbol file contains DWARF 2
4189 GDB now includes basic Java language support. This support is
4190 only useful with Java compilers that produce native machine code.
4192 * solib-absolute-prefix and solib-search-path
4194 For SunOS and SVR4 shared libraries, you may now set the prefix for
4195 loading absolute shared library symbol files, and the search path for
4196 locating non-absolute shared library symbol files.
4198 * Live range splitting
4200 GDB can now effectively debug code for which GCC has performed live
4201 range splitting as part of its optimization. See gdb/doc/LRS for
4202 more details on the expected format of the stabs information.
4206 GDB's support for the GNU Hurd, including thread debugging, has been
4207 updated to work with current versions of the Hurd.
4211 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4212 instruction set. ARM GDB automatically detects when Thumb
4213 instructions are in use, and adjusts disassembly and backtracing
4218 GDB's MIPS target configurations now handle the MIP16 16-bit
4223 GDB now includes support for overlays; if an executable has been
4224 linked such that multiple sections are based at the same address, GDB
4225 will decide which section to use for symbolic info. You can choose to
4226 control the decision manually, using overlay commands, or implement
4227 additional target-side support and use "overlay load-target" to bring
4228 in the overlay mapping. Do "help overlay" for more detail.
4232 The command "info symbol <address>" displays information about
4233 the symbol at the specified address.
4237 The standard remote protocol now includes an extension that allows
4238 asynchronous collection and display of trace data. This requires
4239 extensive support in the target-side debugging stub. Tracing mode
4240 includes a new interaction mode in GDB and new commands: see the
4241 file tracepoint.c for more details.
4245 Configurations for embedded MIPS now include a simulator contributed
4246 by Cygnus Solutions. The simulator supports the instruction sets
4247 of most MIPS variants.
4251 Sparc configurations may now include the ERC32 simulator contributed
4252 by the European Space Agency. The simulator is not built into
4253 Sparc targets by default; configure with --enable-sim to include it.
4257 For target configurations that may include multiple variants of a
4258 basic architecture (such as MIPS and SH), you may now set the
4259 architecture explicitly. "set arch" sets, "info arch" lists
4260 the possible architectures.
4262 *** Changes in GDB-4.16:
4264 * New native configurations
4266 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4267 M68K NetBSD m68k-*-netbsd*
4268 PowerPC AIX 4.x powerpc-*-aix*
4269 PowerPC MacOS powerpc-*-macos*
4270 PowerPC Windows NT powerpcle-*-cygwin32
4271 RS/6000 AIX 4.x rs6000-*-aix4*
4275 ARM with RDP protocol arm-*-*
4276 I960 with MON960 i960-*-coff
4277 MIPS VxWorks mips*-*-vxworks*
4278 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4279 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4281 Matra Sparclet sparclet-*-*
4285 The powerpc-eabi configuration now includes the PSIM simulator,
4286 contributed by Andrew Cagney, with assistance from Mike Meissner.
4287 PSIM is a very elaborate model of the PowerPC, including not only
4288 basic instruction set execution, but also details of execution unit
4289 performance and I/O hardware. See sim/ppc/README for more details.
4293 GDB now works with Solaris 2.5.
4295 * Windows 95/NT native
4297 GDB will now work as a native debugger on Windows 95 and Windows NT.
4298 To build it from source, you must use the "gnu-win32" environment,
4299 which uses a DLL to emulate enough of Unix to run the GNU tools.
4300 Further information, binaries, and sources are available at
4301 ftp.cygnus.com, under pub/gnu-win32.
4303 * dont-repeat command
4305 If a user-defined command includes the command `dont-repeat', then the
4306 command will not be repeated if the user just types return. This is
4307 useful if the command is time-consuming to run, so that accidental
4308 extra keystrokes don't run the same command many times.
4310 * Send break instead of ^C
4312 The standard remote protocol now includes an option to send a break
4313 rather than a ^C to the target in order to interrupt it. By default,
4314 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4316 * Remote protocol timeout
4318 The standard remote protocol includes a new variable `remotetimeout'
4319 that allows you to set the number of seconds before GDB gives up trying
4320 to read from the target. The default value is 2.
4322 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4324 By default GDB will automatically keep track of objects as they are
4325 loaded and unloaded by the dynamic linker. By using the command `set
4326 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4327 when shared library events occur, thus allowing you to set breakpoints
4328 in shared libraries which are explicitly loaded by the inferior.
4330 Note this feature does not work on hpux8. On hpux9 you must link
4331 /usr/lib/end.o into your program. This feature should work
4332 automatically on hpux10.
4334 * Irix 5.x hardware watchpoint support
4336 Irix 5 configurations now support the use of hardware watchpoints.
4338 * Mips protocol "SYN garbage limit"
4340 When debugging a Mips target using the `target mips' protocol, you
4341 may set the number of characters that GDB will ignore by setting
4342 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4343 every character. The default value is 1050.
4345 * Recording and replaying remote debug sessions
4347 If you set `remotelogfile' to the name of a file, gdb will write to it
4348 a recording of a remote debug session. This recording may then be
4349 replayed back to gdb using "gdbreplay". See gdbserver/README for
4350 details. This is useful when you have a problem with GDB while doing
4351 remote debugging; you can make a recording of the session and send it
4352 to someone else, who can then recreate the problem.
4354 * Speedups for remote debugging
4356 GDB includes speedups for downloading and stepping MIPS systems using
4357 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4358 and more efficient S-record downloading.
4360 * Memory use reductions and statistics collection
4362 GDB now uses less memory and reports statistics about memory usage.
4363 Try the `maint print statistics' command, for example.
4365 *** Changes in GDB-4.15:
4367 * Psymtabs for XCOFF
4369 The symbol reader for AIX GDB now uses partial symbol tables. This
4370 can greatly improve startup time, especially for large executables.
4372 * Remote targets use caching
4374 Remote targets now use a data cache to speed up communication with the
4375 remote side. The data cache could lead to incorrect results because
4376 it doesn't know about volatile variables, thus making it impossible to
4377 debug targets which use memory mapped I/O devices. `set remotecache
4378 off' turns the the data cache off.
4380 * Remote targets may have threads
4382 The standard remote protocol now includes support for multiple threads
4383 in the target system, using new protocol commands 'H' and 'T'. See
4384 gdb/remote.c for details.
4388 If GDB is configured with `--enable-netrom', then it will include
4389 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4390 acts as though it is a bank of ROM on the target board, but you can
4391 write into it over the network. GDB's support consists only of
4392 support for fast loading into the emulated ROM; to debug, you must use
4393 another protocol, such as standard remote protocol. The usual
4394 sequence is something like
4396 target nrom <netrom-hostname>
4398 target remote <netrom-hostname>:1235
4402 GDB now includes support for the Apple Macintosh, as a host only. It
4403 may be run as either an MPW tool or as a standalone application, and
4404 it can debug through the serial port. All the usual GDB commands are
4405 available, but to the target command, you must supply "serial" as the
4406 device type instead of "/dev/ttyXX". See mpw-README in the main
4407 directory for more information on how to build. The MPW configuration
4408 scripts */mpw-config.in support only a few targets, and only the
4409 mips-idt-ecoff target has been tested.
4413 GDB configuration now uses autoconf. This is not user-visible,
4414 but does simplify configuration and building.
4418 GDB now supports hpux10.
4420 *** Changes in GDB-4.14:
4422 * New native configurations
4424 x86 FreeBSD i[345]86-*-freebsd
4425 x86 NetBSD i[345]86-*-netbsd
4426 NS32k NetBSD ns32k-*-netbsd
4427 Sparc NetBSD sparc-*-netbsd
4431 A29K VxWorks a29k-*-vxworks
4432 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4433 CPU32 EST-300 emulator m68*-*-est*
4434 PowerPC ELF powerpc-*-elf
4437 * Alpha OSF/1 support for procfs
4439 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4440 possible to attach to running processes. As the mounting of the /proc
4441 filesystem is optional on the Alpha, GDB automatically determines
4442 the availability of /proc during startup. This can lead to problems
4443 if /proc is unmounted after GDB has been started.
4445 * Arguments to user-defined commands
4447 User commands may accept up to 10 arguments separated by whitespace.
4448 Arguments are accessed within the user command via $arg0..$arg9. A
4451 print $arg0 + $arg1 + $arg2
4453 To execute the command use:
4456 Defines the command "adder" which prints the sum of its three arguments.
4457 Note the arguments are text substitutions, so they may reference variables,
4458 use complex expressions, or even perform inferior function calls.
4460 * New `if' and `while' commands
4462 This makes it possible to write more sophisticated user-defined
4463 commands. Both commands take a single argument, which is the
4464 expression to evaluate, and must be followed by the commands to
4465 execute, one per line, if the expression is nonzero, the list being
4466 terminated by the word `end'. The `if' command list may include an
4467 `else' word, which causes the following commands to be executed only
4468 if the expression is zero.
4470 * Fortran source language mode
4472 GDB now includes partial support for Fortran 77. It will recognize
4473 Fortran programs and can evaluate a subset of Fortran expressions, but
4474 variables and functions may not be handled correctly. GDB will work
4475 with G77, but does not yet know much about symbols emitted by other
4478 * Better HPUX support
4480 Most debugging facilities now work on dynamic executables for HPPAs
4481 running hpux9 or later. You can attach to running dynamically linked
4482 processes, but by default the dynamic libraries will be read-only, so
4483 for instance you won't be able to put breakpoints in them. To change
4484 that behavior do the following before running the program:
4490 This will cause the libraries to be mapped private and read-write.
4491 To revert to the normal behavior, do this:
4497 You cannot set breakpoints or examine data in the library until after
4498 the library is loaded if the function/data symbols do not have
4501 GDB can now also read debug symbols produced by the HP C compiler on
4502 HPPAs (sorry, no C++, Fortran or 68k support).
4504 * Target byte order now dynamically selectable
4506 You can choose which byte order to use with a target system, via the
4507 commands "set endian big" and "set endian little", and you can see the
4508 current setting by using "show endian". You can also give the command
4509 "set endian auto", in which case GDB will use the byte order
4510 associated with the executable. Currently, only embedded MIPS
4511 configurations support dynamic selection of target byte order.
4513 * New DOS host serial code
4515 This version uses DPMI interrupts to handle buffered I/O, so you
4516 no longer need to run asynctsr when debugging boards connected to
4519 *** Changes in GDB-4.13:
4521 * New "complete" command
4523 This lists all the possible completions for the rest of the line, if it
4524 were to be given as a command itself. This is intended for use by emacs.
4526 * Trailing space optional in prompt
4528 "set prompt" no longer adds a space for you after the prompt you set. This
4529 allows you to set a prompt which ends in a space or one that does not.
4531 * Breakpoint hit counts
4533 "info break" now displays a count of the number of times the breakpoint
4534 has been hit. This is especially useful in conjunction with "ignore"; you
4535 can ignore a large number of breakpoint hits, look at the breakpoint info
4536 to see how many times the breakpoint was hit, then run again, ignoring one
4537 less than that number, and this will get you quickly to the last hit of
4540 * Ability to stop printing at NULL character
4542 "set print null-stop" will cause GDB to stop printing the characters of
4543 an array when the first NULL is encountered. This is useful when large
4544 arrays actually contain only short strings.
4546 * Shared library breakpoints
4548 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4549 breakpoints in shared libraries before the executable is run.
4551 * Hardware watchpoints
4553 There is a new hardware breakpoint for the watch command for sparclite
4554 targets. See gdb/sparclite/hw_breakpoint.note.
4556 Hardware watchpoints are also now supported under GNU/Linux.
4560 Annotations have been added. These are for use with graphical interfaces,
4561 and are still experimental. Currently only gdba.el uses these.
4563 * Improved Irix 5 support
4565 GDB now works properly with Irix 5.2.
4567 * Improved HPPA support
4569 GDB now works properly with the latest GCC and GAS.
4571 * New native configurations
4573 Sequent PTX4 i[34]86-sequent-ptx4
4574 HPPA running OSF/1 hppa*-*-osf*
4575 Atari TT running SVR4 m68*-*-sysv4*
4576 RS/6000 LynxOS rs6000-*-lynxos*
4580 OS/9000 i[34]86-*-os9k
4581 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4584 * Hitachi SH7000 and E7000-PC ICE support
4586 There is now support for communicating with the Hitachi E7000-PC ICE.
4587 This is available automatically when GDB is configured for the SH.
4591 As usual, a variety of small fixes and improvements, both generic
4592 and configuration-specific. See the ChangeLog for more detail.
4594 *** Changes in GDB-4.12:
4596 * Irix 5 is now supported
4600 GDB-4.12 on the HPPA has a number of changes which make it unable
4601 to debug the output from the currently released versions of GCC and
4602 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4603 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4604 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4607 *** Changes in GDB-4.11:
4609 * User visible changes:
4613 The "set remotedebug" option is now consistent between the mips remote
4614 target, remote targets using the gdb-specific protocol, UDI (AMD's
4615 debug protocol for the 29k) and the 88k bug monitor. It is now an
4616 integer specifying a debug level (normally 0 or 1, but 2 means more
4617 debugging info for the mips target).
4619 * DEC Alpha native support
4621 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4622 debug info, but GDB works fairly well with the DEC compiler and should
4623 work with a future GCC release. See the README file for a few
4624 Alpha-specific notes.
4626 * Preliminary thread implementation
4628 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4630 * LynxOS native and target support for 386
4632 This release has been hosted on LynxOS 2.2, and also can be configured
4633 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4636 * Improvements in C++ mangling/demangling.
4638 This release has much better g++ debugging, specifically in name
4639 mangling/demangling, virtual function calls, print virtual table,
4640 call methods, ...etc.
4642 *** Changes in GDB-4.10:
4644 * User visible changes:
4646 Remote debugging using the GDB-specific (`target remote') protocol now
4647 supports the `load' command. This is only useful if you have some
4648 other way of getting the stub to the target system, and you can put it
4649 somewhere in memory where it won't get clobbered by the download.
4651 Filename completion now works.
4653 When run under emacs mode, the "info line" command now causes the
4654 arrow to point to the line specified. Also, "info line" prints
4655 addresses in symbolic form (as well as hex).
4657 All vxworks based targets now support a user settable option, called
4658 vxworks-timeout. This option represents the number of seconds gdb
4659 should wait for responses to rpc's. You might want to use this if
4660 your vxworks target is, perhaps, a slow software simulator or happens
4661 to be on the far side of a thin network line.
4665 This release contains support for using a DEC alpha as a GDB host for
4666 cross debugging. Native alpha debugging is not supported yet.
4669 *** Changes in GDB-4.9:
4673 This is the first GDB release which is accompanied by a matching testsuite.
4674 The testsuite requires installation of dejagnu, which should be available
4675 via ftp from most sites that carry GNU software.
4679 'Cfront' style demangling has had its name changed to 'ARM' style, to
4680 emphasize that it was written from the specifications in the C++ Annotated
4681 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4682 disclaimers, it still generated too much confusion with users attempting to
4683 use gdb with AT&T cfront.
4687 GDB now uses a standard remote interface to a simulator library.
4688 So far, the library contains simulators for the Zilog Z8001/2, the
4689 Hitachi H8/300, H8/500 and Super-H.
4691 * New targets supported
4693 H8/300 simulator h8300-hitachi-hms or h8300hms
4694 H8/500 simulator h8500-hitachi-hms or h8500hms
4695 SH simulator sh-hitachi-hms or sh
4696 Z8000 simulator z8k-zilog-none or z8ksim
4697 IDT MIPS board over serial line mips-idt-ecoff
4699 Cross-debugging to GO32 targets is supported. It requires a custom
4700 version of the i386-stub.c module which is integrated with the
4701 GO32 memory extender.
4703 * New remote protocols
4705 MIPS remote debugging protocol.
4707 * New source languages supported
4709 This version includes preliminary support for Chill, a Pascal like language
4710 used by telecommunications companies. Chill support is also being integrated
4711 into the GNU compiler, but we don't know when it will be publically available.
4714 *** Changes in GDB-4.8:
4716 * HP Precision Architecture supported
4718 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4719 version of this support was available as a set of patches from the
4720 University of Utah. GDB does not support debugging of programs
4721 compiled with the HP compiler, because HP will not document their file
4722 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4723 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4725 Many problems in the preliminary version have been fixed.
4727 * Faster and better demangling
4729 We have improved template demangling and fixed numerous bugs in the GNU style
4730 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4731 character types (wchar_t) are now supported. Demangling of each symbol is now
4732 only done once, and is cached when the symbol table for a file is read in.
4733 This results in a small increase in memory usage for C programs, a moderate
4734 increase in memory usage for C++ programs, and a fantastic speedup in
4737 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4738 from the specifications in the Annotated Reference Manual, which AT&T's
4739 compiler does not actually implement.
4741 * G++ multiple inheritance compiler problem
4743 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4744 inheritance lattices was reworked to properly discover ambiguities. We
4745 recently found an example which causes this new algorithm to fail in a
4746 very subtle way, producing bad debug information for those classes.
4747 The file 'gcc.patch' (in this directory) can be applied to gcc to
4748 circumvent the problem. A future GCC release will contain a complete
4751 The previous G++ debug info problem (mentioned below for the gdb-4.7
4752 release) is fixed in gcc version 2.3.2.
4754 * Improved configure script
4756 The `configure' script will now attempt to guess your system type if
4757 you don't supply a host system type. The old scheme of supplying a
4758 host system triplet is preferable over using this. All the magic is
4759 done in the new `config.guess' script. Examine it for details.
4761 We have also brought our configure script much more in line with the FSF's
4762 version. It now supports the --with-xxx options. In particular,
4763 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4764 The resulting GDB will not be able to read arbitrary object file formats --
4765 only the format ``expected'' to be used on the configured target system.
4766 We hope to make this the default in a future release.
4768 * Documentation improvements
4770 There's new internal documentation on how to modify GDB, and how to
4771 produce clean changes to the code. We implore people to read it
4772 before submitting changes.
4774 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4775 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4776 `info' files are also provided. To build `info' files from scratch,
4777 you will need the latest `makeinfo' release, which will be available in
4778 a future texinfo-X.Y release.
4780 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4781 We're not sure exactly which versions have this problem, but it has
4782 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4783 or better. If that isn't possible, there is a patch in
4784 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4785 around this problem.
4789 GDB now supports array constants that can be used in expressions typed in by
4790 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4791 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4794 The new directory `gdb/sparclite' contains a program that demonstrates
4795 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4797 * New native hosts supported
4799 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4800 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4802 * New targets supported
4804 AMD 29k family via UDI a29k-amd-udi or udi29k
4806 * New file formats supported
4808 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4809 HPUX core files, and SCO 3.2v2 core files.
4813 Attaching to processes now works again; thanks for the many bug reports.
4815 We have also stomped on a bunch of core dumps caused by
4816 printf_filtered("%s") problems.
4818 We eliminated a copyright problem on the rpc and ptrace header files
4819 for VxWorks, which was discovered at the last minute during the 4.7
4820 release. You should now be able to build a VxWorks GDB.
4822 You can now interrupt gdb while an attached process is running. This
4823 will cause the attached process to stop, and give control back to GDB.
4825 We fixed problems caused by using too many file descriptors
4826 for reading symbols from object files and libraries. This was
4827 especially a problem for programs that used many (~100) shared
4830 The `step' command now only enters a subroutine if there is line number
4831 information for the subroutine. Otherwise it acts like the `next'
4832 command. Previously, `step' would enter subroutines if there was
4833 any debugging information about the routine. This avoids problems
4834 when using `cc -g1' on MIPS machines.
4836 * Internal improvements
4838 GDB's internal interfaces have been improved to make it easier to support
4839 debugging of multiple languages in the future.
4841 GDB now uses a common structure for symbol information internally.
4842 Minimal symbols (derived from linkage symbols in object files), partial
4843 symbols (from a quick scan of debug information), and full symbols
4844 contain a common subset of information, making it easier to write
4845 shared code that handles any of them.
4847 * New command line options
4849 We now accept --silent as an alias for --quiet.
4853 The memory-mapped-malloc library is now licensed under the GNU Library
4854 General Public License.
4856 *** Changes in GDB-4.7:
4858 * Host/native/target split
4860 GDB has had some major internal surgery to untangle the support for
4861 hosts and remote targets. Now, when you configure GDB for a remote
4862 target, it will no longer load in all of the support for debugging
4863 local programs on the host. When fully completed and tested, this will
4864 ensure that arbitrary host/target combinations are possible.
4866 The primary conceptual shift is to separate the non-portable code in
4867 GDB into three categories. Host specific code is required any time GDB
4868 is compiled on that host, regardless of the target. Target specific
4869 code relates to the peculiarities of the target, but can be compiled on
4870 any host. Native specific code is everything else: it can only be
4871 built when the host and target are the same system. Child process
4872 handling and core file support are two common `native' examples.
4874 GDB's use of /proc for controlling Unix child processes is now cleaner.
4875 It has been split out into a single module under the `target_ops' vector,
4876 plus two native-dependent functions for each system that uses /proc.
4878 * New hosts supported
4880 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4881 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4882 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4884 * New targets supported
4886 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4887 68030 and CPU32 m68030-*-*, m68332-*-*
4889 * New native hosts supported
4891 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4892 (386bsd is not well tested yet)
4893 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4895 * New file formats supported
4897 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4898 supports reading of `a.out.adobe' object files, which are an a.out
4899 format extended with minimal information about multiple sections.
4903 `show copying' is the same as the old `info copying'.
4904 `show warranty' is the same as `info warrantee'.
4905 These were renamed for consistency. The old commands continue to work.
4907 `info handle' is a new alias for `info signals'.
4909 You can now define pre-command hooks, which attach arbitrary command
4910 scripts to any command. The commands in the hook will be executed
4911 prior to the user's command. You can also create a hook which will be
4912 executed whenever the program stops. See gdb.texinfo.
4916 We now deal with Cfront style name mangling, and can even extract type
4917 info from mangled symbols. GDB can automatically figure out which
4918 symbol mangling style your C++ compiler uses.
4920 Calling of methods and virtual functions has been improved as well.
4924 The crash that occured when debugging Sun Ansi-C compiled binaries is
4925 fixed. This was due to mishandling of the extra N_SO stabs output
4928 We also finally got Ultrix 4.2 running in house, and fixed core file
4929 support, with help from a dozen people on the net.
4931 John M. Farrell discovered that the reason that single-stepping was so
4932 slow on all of the Mips based platforms (primarily SGI and DEC) was
4933 that we were trying to demangle and lookup a symbol used for internal
4934 purposes on every instruction that was being stepped through. Changing
4935 the name of that symbol so that it couldn't be mistaken for a C++
4936 mangled symbol sped things up a great deal.
4938 Rich Pixley sped up symbol lookups in general by getting much smarter
4939 about when C++ symbol mangling is necessary. This should make symbol
4940 completion (TAB on the command line) much faster. It's not as fast as
4941 we'd like, but it's significantly faster than gdb-4.6.
4945 A new user controllable variable 'call_scratch_address' can
4946 specify the location of a scratch area to be used when GDB
4947 calls a function in the target. This is necessary because the
4948 usual method of putting the scratch area on the stack does not work
4949 in systems that have separate instruction and data spaces.
4951 We integrated changes to support the 29k UDI (Universal Debugger
4952 Interface), but discovered at the last minute that we didn't have all
4953 of the appropriate copyright paperwork. We are working with AMD to
4954 resolve this, and hope to have it available soon.
4958 We have sped up the remote serial line protocol, especially for targets
4959 with lots of registers. It now supports a new `expedited status' ('T')
4960 message which can be used in place of the existing 'S' status message.
4961 This allows the remote stub to send only the registers that GDB
4962 needs to make a quick decision about single-stepping or conditional
4963 breakpoints, eliminating the need to fetch the entire register set for
4964 each instruction being stepped through.
4966 The GDB remote serial protocol now implements a write-through cache for
4967 registers, only re-reading the registers if the target has run.
4969 There is also a new remote serial stub for SPARC processors. You can
4970 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4971 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4972 processor with a serial port.
4976 Configure.in files have become much easier to read and modify. A new
4977 `table driven' format makes it more obvious what configurations are
4978 supported, and what files each one uses.
4982 There is a new opcodes library which will eventually contain all of the
4983 disassembly routines and opcode tables. At present, it only contains
4984 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4985 disassembler (binutils/objdump) to share these routines.
4987 The libiberty library is now copylefted under the GNU Library General
4988 Public License. This allows more liberal use, and was done so libg++
4989 can use it. This makes no difference to GDB, since the Library License
4990 grants all the rights from the General Public License.
4994 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4995 reference to the stabs symbol info used by the debugger. It is (as far
4996 as we know) the only published document on this fascinating topic. We
4997 encourage you to read it, compare it to the stabs information on your
4998 system, and send improvements on the document in general (to
4999 bug-gdb@prep.ai.mit.edu).
5001 And, of course, many bugs have been fixed.
5004 *** Changes in GDB-4.6:
5006 * Better support for C++ function names
5008 GDB now accepts as input the "demangled form" of C++ overloaded function
5009 names and member function names, and can do command completion on such names
5010 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5011 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5012 Make use of command completion, it is your friend.
5014 GDB also now accepts a variety of C++ mangled symbol formats. They are
5015 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5016 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5017 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5018 for the list of formats.
5020 * G++ symbol mangling problem
5022 Recent versions of gcc have a bug in how they emit debugging information for
5023 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5024 directory) can be applied to gcc to fix the problem. Alternatively, if you
5025 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5026 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5027 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5030 * New 'maintenance' command
5032 All of the commands related to hacking GDB internals have been moved out of
5033 the main command set, and now live behind the 'maintenance' command. This
5034 can also be abbreviated as 'mt'. The following changes were made:
5036 dump-me -> maintenance dump-me
5037 info all-breakpoints -> maintenance info breakpoints
5038 printmsyms -> maintenance print msyms
5039 printobjfiles -> maintenance print objfiles
5040 printpsyms -> maintenance print psymbols
5041 printsyms -> maintenance print symbols
5043 The following commands are new:
5045 maintenance demangle Call internal GDB demangler routine to
5046 demangle a C++ link name and prints the result.
5047 maintenance print type Print a type chain for a given symbol
5049 * Change to .gdbinit file processing
5051 We now read the $HOME/.gdbinit file before processing the argv arguments
5052 (e.g. reading symbol files or core files). This allows global parameters to
5053 be set, which will apply during the symbol reading. The ./.gdbinit is still
5054 read after argv processing.
5056 * New hosts supported
5058 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5060 GNU/Linux support i386-unknown-linux or linux
5062 We are also including code to support the HP/PA running BSD and HPUX. This
5063 is almost guaranteed not to work, as we didn't have time to test or build it
5064 for this release. We are including it so that the more adventurous (or
5065 masochistic) of you can play with it. We also had major problems with the
5066 fact that the compiler that we got from HP doesn't support the -g option.
5069 * New targets supported
5071 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5073 * More smarts about finding #include files
5075 GDB now remembers the compilation directory for all include files, and for
5076 all files from which C is generated (like yacc and lex sources). This
5077 greatly improves GDB's ability to find yacc/lex sources, and include files,
5078 especially if you are debugging your program from a directory different from
5079 the one that contains your sources.
5081 We also fixed a bug which caused difficulty with listing and setting
5082 breakpoints in include files which contain C code. (In the past, you had to
5083 try twice in order to list an include file that you hadn't looked at before.)
5085 * Interesting infernals change
5087 GDB now deals with arbitrary numbers of sections, where the symbols for each
5088 section must be relocated relative to that section's landing place in the
5089 target's address space. This work was needed to support ELF with embedded
5090 stabs used by Solaris-2.0.
5092 * Bug fixes (of course!)
5094 There have been loads of fixes for the following things:
5095 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5096 i960, stabs, DOS(GO32), procfs, etc...
5098 See the ChangeLog for details.
5100 *** Changes in GDB-4.5:
5102 * New machines supported (host and target)
5104 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5106 SGI Irix-4.x mips-sgi-irix4 or iris4
5108 * New malloc package
5110 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5111 Mmalloc is capable of handling mutiple heaps of memory. It is also
5112 capable of saving a heap to a file, and then mapping it back in later.
5113 This can be used to greatly speedup the startup of GDB by using a
5114 pre-parsed symbol table which lives in a mmalloc managed heap. For
5115 more details, please read mmalloc/mmalloc.texi.
5119 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5120 'help info proc' for details.
5122 * MIPS ecoff symbol table format
5124 The code that reads MIPS symbol table format is now supported on all hosts.
5125 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5128 * File name changes for MS-DOS
5130 Many files in the config directories have been renamed to make it easier to
5131 support GDB on MS-DOSe systems (which have very restrictive file name
5132 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5133 environment) is close to working but has some remaining problems. Note
5134 that debugging of DOS programs is not supported, due to limitations
5135 in the ``operating system'', but it can be used to host cross-debugging.
5137 * Cross byte order fixes
5139 Many fixes have been made to support cross debugging of Sparc and MIPS
5140 targets from hosts whose byte order differs.
5142 * New -mapped and -readnow options
5144 If memory-mapped files are available on your system through the 'mmap'
5145 system call, you can use the -mapped option on the `file' or
5146 `symbol-file' commands to cause GDB to write the symbols from your
5147 program into a reusable file. If the program you are debugging is
5148 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5149 Future GDB debugging sessions will notice the presence of this file,
5150 and will quickly map in symbol information from it, rather than reading
5151 the symbol table from the executable program. Using the '-mapped'
5152 option in a GDB `file' or `symbol-file' command has the same effect as
5153 starting GDB with the '-mapped' command-line option.
5155 You can cause GDB to read the entire symbol table immediately by using
5156 the '-readnow' option with any of the commands that load symbol table
5157 information (or on the GDB command line). This makes the command
5158 slower, but makes future operations faster.
5160 The -mapped and -readnow options are typically combined in order to
5161 build a `fred.syms' file that contains complete symbol information.
5162 A simple GDB invocation to do nothing but build a `.syms' file for future
5165 gdb -batch -nx -mapped -readnow programname
5167 The `.syms' file is specific to the host machine on which GDB is run.
5168 It holds an exact image of GDB's internal symbol table. It cannot be
5169 shared across multiple host platforms.
5171 * longjmp() handling
5173 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5174 siglongjmp() without losing control. This feature has not yet been ported to
5175 all systems. It currently works on many 386 platforms, all MIPS-based
5176 platforms (SGI, DECstation, etc), and Sun3/4.
5180 Preliminary work has been put in to support the new Solaris OS from Sun. At
5181 this time, it can control and debug processes, but it is not capable of
5186 As always, many many bug fixes. The major areas were with g++, and mipsread.
5187 People using the MIPS-based platforms should experience fewer mysterious
5188 crashes and trashed symbol tables.
5190 *** Changes in GDB-4.4:
5192 * New machines supported (host and target)
5194 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5196 BSD Reno on Vax vax-dec-bsd
5197 Ultrix on Vax vax-dec-ultrix
5199 * New machines supported (target)
5201 AMD 29000 embedded, using EBMON a29k-none-none
5205 GDB continues to improve its handling of C++. `References' work better.
5206 The demangler has also been improved, and now deals with symbols mangled as
5207 per the Annotated C++ Reference Guide.
5209 GDB also now handles `stabs' symbol information embedded in MIPS
5210 `ecoff' symbol tables. Since the ecoff format was not easily
5211 extensible to handle new languages such as C++, this appeared to be a
5212 good way to put C++ debugging info into MIPS binaries. This option
5213 will be supported in the GNU C compiler, version 2, when it is
5216 * New features for SVR4
5218 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5219 shared libraries. Debugging dynamically linked programs should present
5220 only minor differences from debugging statically linked programs.
5222 The `info proc' command will print out information about any process
5223 on an SVR4 system (including the one you are debugging). At the moment,
5224 it prints the address mappings of the process.
5226 If you bring up GDB on another SVR4 system, please send mail to
5227 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5229 * Better dynamic linking support in SunOS
5231 Reading symbols from shared libraries which contain debugging symbols
5232 now works properly. However, there remain issues such as automatic
5233 skipping of `transfer vector' code during function calls, which
5234 make it harder to debug code in a shared library, than to debug the
5235 same code linked statically.
5239 GDB is now using the latest `getopt' routines from the FSF. This
5240 version accepts the -- prefix for options with long names. GDB will
5241 continue to accept the old forms (-option and +option) as well.
5242 Various single letter abbreviations for options have been explicity
5243 added to the option table so that they won't get overshadowed in the
5244 future by other options that begin with the same letter.
5248 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5249 Many assorted bugs have been handled. Many more remain to be handled.
5250 See the various ChangeLog files (primarily in gdb and bfd) for details.
5253 *** Changes in GDB-4.3:
5255 * New machines supported (host and target)
5257 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5258 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5259 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5261 * Almost SCO Unix support
5263 We had hoped to support:
5264 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5265 (except for core file support), but we discovered very late in the release
5266 that it has problems with process groups that render gdb unusable. Sorry
5267 about that. I encourage people to fix it and post the fixes.
5269 * Preliminary ELF and DWARF support
5271 GDB can read ELF object files on System V Release 4, and can handle
5272 debugging records for C, in DWARF format, in ELF files. This support
5273 is preliminary. If you bring up GDB on another SVR4 system, please
5274 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5279 GDB now uses the latest `readline' library. One user-visible change
5280 is that two tabs will list possible command completions, which previously
5281 required typing M-? (meta-question mark, or ESC ?).
5285 The `stepi' bug that many of you noticed has been squashed.
5286 Many bugs in C++ have been handled. Many more remain to be handled.
5287 See the various ChangeLog files (primarily in gdb and bfd) for details.
5289 * State of the MIPS world (in case you wondered):
5291 GDB can understand the symbol tables emitted by the compilers
5292 supplied by most vendors of MIPS-based machines, including DEC. These
5293 symbol tables are in a format that essentially nobody else uses.
5295 Some versions of gcc come with an assembler post-processor called
5296 mips-tfile. This program is required if you want to do source-level
5297 debugging of gcc-compiled programs. I believe FSF does not ship
5298 mips-tfile with gcc version 1, but it will eventually come with gcc
5301 Debugging of g++ output remains a problem. g++ version 1.xx does not
5302 really support it at all. (If you're lucky, you should be able to get
5303 line numbers and stack traces to work, but no parameters or local
5304 variables.) With some work it should be possible to improve the
5307 When gcc version 2 is released, you will have somewhat better luck.
5308 However, even then you will get confusing results for inheritance and
5311 We will eventually provide full debugging of g++ output on
5312 DECstations. This will probably involve some kind of stabs-in-ecoff
5313 encapulation, but the details have not been worked out yet.
5316 *** Changes in GDB-4.2:
5318 * Improved configuration
5320 Only one copy of `configure' exists now, and it is not self-modifying.
5321 Porting BFD is simpler.
5325 The `step' and `next' commands now only stop at the first instruction
5326 of a source line. This prevents the multiple stops that used to occur
5327 in switch statements, for-loops, etc. `Step' continues to stop if a
5328 function that has debugging information is called within the line.
5332 Lots of small bugs fixed. More remain.
5334 * New host supported (not target)
5336 Intel 386 PC clone running Mach i386-none-mach
5339 *** Changes in GDB-4.1:
5341 * Multiple source language support
5343 GDB now has internal scaffolding to handle several source languages.
5344 It determines the type of each source file from its filename extension,
5345 and will switch expression parsing and number formatting to match the
5346 language of the function in the currently selected stack frame.
5347 You can also specifically set the language to be used, with
5348 `set language c' or `set language modula-2'.
5352 GDB now has preliminary support for the GNU Modula-2 compiler,
5353 currently under development at the State University of New York at
5354 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5355 continue through the fall of 1991 and into 1992.
5357 Other Modula-2 compilers are currently not supported, and attempting to
5358 debug programs compiled with them will likely result in an error as the
5359 symbol table is read. Feel free to work on it, though!
5361 There are hooks in GDB for strict type checking and range checking,
5362 in the `Modula-2 philosophy', but they do not currently work.
5366 GDB can now write to executable and core files (e.g. patch
5367 a variable's value). You must turn this switch on, specify
5368 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5369 by assigning a new value to a variable. Modifications take
5372 * Automatic SunOS shared library reading
5374 When you run your program, GDB automatically determines where its
5375 shared libraries (if any) have been loaded, and reads their symbols.
5376 The `share' command is no longer needed. This also works when
5377 examining core files.
5381 You can specify the number of lines that the `list' command shows.
5384 * New machines supported (host and target)
5386 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5387 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5388 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5390 * New hosts supported (not targets)
5392 IBM RT/PC: romp-ibm-aix or rtpc
5394 * New targets supported (not hosts)
5396 AMD 29000 embedded with COFF a29k-none-coff
5397 AMD 29000 embedded with a.out a29k-none-aout
5398 Ultracomputer remote kernel debug a29k-nyu-kern
5400 * New remote interfaces
5406 *** Changes in GDB-4.0:
5410 Wide output is wrapped at good places to make the output more readable.
5412 Gdb now supports cross-debugging from a host machine of one type to a
5413 target machine of another type. Communication with the target system
5414 is over serial lines. The ``target'' command handles connecting to the
5415 remote system; the ``load'' command will download a program into the
5416 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5417 also supports debugging of realtime processes running under VxWorks,
5418 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5419 stub on the target system.
5421 New CPUs supported include the AMD 29000 and Intel 960.
5423 GDB now reads object files and symbol tables via a ``binary file''
5424 library, which allows a single copy of GDB to debug programs of multiple
5425 object file types such as a.out and coff.
5427 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5428 refcard.dvi and refcard.ps are available to format it).
5431 * Control-Variable user interface simplified
5433 All variables that control the operation of the debugger can be set
5434 by the ``set'' command, and displayed by the ``show'' command.
5436 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5437 ``Show prompt'' produces the response:
5438 Gdb's prompt is new-gdb=>.
5440 What follows are the NEW set commands. The command ``help set'' will
5441 print a complete list of old and new set commands. ``help set FOO''
5442 will give a longer description of the variable FOO. ``show'' will show
5443 all of the variable descriptions and their current settings.
5445 confirm on/off: Enables warning questions for operations that are
5446 hard to recover from, e.g. rerunning the program while
5447 it is already running. Default is ON.
5449 editing on/off: Enables EMACS style command line editing
5450 of input. Previous lines can be recalled with
5451 control-P, the current line can be edited with control-B,
5452 you can search for commands with control-R, etc.
5455 history filename NAME: NAME is where the gdb command history
5456 will be stored. The default is .gdb_history,
5457 or the value of the environment variable
5460 history size N: The size, in commands, of the command history. The
5461 default is 256, or the value of the environment variable
5464 history save on/off: If this value is set to ON, the history file will
5465 be saved after exiting gdb. If set to OFF, the
5466 file will not be saved. The default is OFF.
5468 history expansion on/off: If this value is set to ON, then csh-like
5469 history expansion will be performed on
5470 command line input. The default is OFF.
5472 radix N: Sets the default radix for input and output. It can be set
5473 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5474 in the current radix, so "set radix 10" is always a no-op.
5476 height N: This integer value is the number of lines on a page. Default
5477 is 24, the current `stty rows'' setting, or the ``li#''
5478 setting from the termcap entry matching the environment
5481 width N: This integer value is the number of characters on a line.
5482 Default is 80, the current `stty cols'' setting, or the ``co#''
5483 setting from the termcap entry matching the environment
5486 Note: ``set screensize'' is obsolete. Use ``set height'' and
5487 ``set width'' instead.
5489 print address on/off: Print memory addresses in various command displays,
5490 such as stack traces and structure values. Gdb looks
5491 more ``symbolic'' if you turn this off; it looks more
5492 ``machine level'' with it on. Default is ON.
5494 print array on/off: Prettyprint arrays. New convenient format! Default
5497 print demangle on/off: Print C++ symbols in "source" form if on,
5500 print asm-demangle on/off: Same, for assembler level printouts
5503 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5506 * Support for Epoch Environment.
5508 The epoch environment is a version of Emacs v18 with windowing. One
5509 new command, ``inspect'', is identical to ``print'', except that if you
5510 are running in the epoch environment, the value is printed in its own
5514 * Support for Shared Libraries
5516 GDB can now debug programs and core files that use SunOS shared libraries.
5517 Symbols from a shared library cannot be referenced
5518 before the shared library has been linked with the program (this
5519 happens after you type ``run'' and before the function main() is entered).
5520 At any time after this linking (including when examining core files
5521 from dynamically linked programs), gdb reads the symbols from each
5522 shared library when you type the ``sharedlibrary'' command.
5523 It can be abbreviated ``share''.
5525 sharedlibrary REGEXP: Load shared object library symbols for files
5526 matching a unix regular expression. No argument
5527 indicates to load symbols for all shared libraries.
5529 info sharedlibrary: Status of loaded shared libraries.
5534 A watchpoint stops execution of a program whenever the value of an
5535 expression changes. Checking for this slows down execution
5536 tremendously whenever you are in the scope of the expression, but is
5537 quite useful for catching tough ``bit-spreader'' or pointer misuse
5538 problems. Some machines such as the 386 have hardware for doing this
5539 more quickly, and future versions of gdb will use this hardware.
5541 watch EXP: Set a watchpoint (breakpoint) for an expression.
5543 info watchpoints: Information about your watchpoints.
5545 delete N: Deletes watchpoint number N (same as breakpoints).
5546 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5547 enable N: Re-enables watchpoint number N (same as breakpoints).
5550 * C++ multiple inheritance
5552 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5555 * C++ exception handling
5557 Gdb now supports limited C++ exception handling. Besides the existing
5558 ability to breakpoint on an exception handler, gdb can breakpoint on
5559 the raising of an exception (before the stack is peeled back to the
5562 catch FOO: If there is a FOO exception handler in the dynamic scope,
5563 set a breakpoint to catch exceptions which may be raised there.
5564 Multiple exceptions (``catch foo bar baz'') may be caught.
5566 info catch: Lists all exceptions which may be caught in the
5567 current stack frame.
5570 * Minor command changes
5572 The command ``call func (arg, arg, ...)'' now acts like the print
5573 command, except it does not print or save a value if the function's result
5574 is void. This is similar to dbx usage.
5576 The ``up'' and ``down'' commands now always print the frame they end up
5577 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5578 frames without printing.
5580 * New directory command
5582 'dir' now adds directories to the FRONT of the source search path.
5583 The path starts off empty. Source files that contain debug information
5584 about the directory in which they were compiled can be found even
5585 with an empty path; Sun CC and GCC include this information. If GDB can't
5586 find your source file in the current directory, type "dir .".
5588 * Configuring GDB for compilation
5590 For normal use, type ``./configure host''. See README or gdb.texinfo
5593 GDB now handles cross debugging. If you are remotely debugging between
5594 two different machines, type ``./configure host -target=targ''.
5595 Host is the machine where GDB will run; targ is the machine
5596 where the program that you are debugging will run.
5598 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.