1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.6
6 * GDB now supports Fission DWP file format version 2.
7 http://gcc.gnu.org/wiki/DebugFission
9 * New convenience function "$_isvoid", to check whether an expression
10 is void. A void expression is an expression where the type of the
11 result is "void". For example, some convenience variables may be
12 "void" when evaluated (e.g., "$_exitcode" before the execution of
13 the program being debugged; or an undefined convenience variable).
14 Another example, when calling a function whose return type is
17 * The "maintenance print objfiles" command now takes an optional regexp.
19 * The "catch syscall" command now works on arm*-linux* targets.
21 * GDB now consistently shows "<not saved>" when printing values of
22 registers the debug info indicates have not been saved in the frame
23 and there's nowhere to retrieve them from
24 (callee-saved/call-clobbered registers):
29 (gdb) info registers rax
32 Before, the former would print "<optimized out>", and the latter
33 "*value not available*".
35 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
40 ** Frame filters and frame decorators have been added.
41 ** Temporary breakpoints are now supported.
42 ** Line tables representation has been added.
43 ** New attribute 'parent_type' for gdb.Field objects.
44 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
48 Nios II ELF nios2*-*-elf
49 Nios II GNU/Linux nios2*-*-linux
50 Texas Instruments MSP430 msp430*-*-elf
52 * Removed native configurations
54 Support for these a.out NetBSD and OpenBSD obsolete configurations has
55 been removed. ELF variants of these configurations are kept supported.
57 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
58 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
59 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
60 i[34567]86-*-openbsd3.[0-3]
61 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
62 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
63 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
67 Like "catch throw", but catches a re-thrown exception.
69 Renamed from old "maint check-symtabs".
71 Perform consistency checks on symtabs.
73 Expand symtabs matching an optional regexp.
76 Display the details of GDB configure-time options.
78 maint set|show per-command
79 maint set|show per-command space
80 maint set|show per-command time
81 maint set|show per-command symtab
82 Enable display of per-command gdb resource usage.
84 remove-symbol-file FILENAME
85 remove-symbol-file -a ADDRESS
86 Remove a symbol file added via add-symbol-file. The file to remove
87 can be identified by its filename or by an address that lies within
88 the boundaries of this symbol file in memory.
91 info exceptions REGEXP
92 Display the list of Ada exceptions defined in the program being
93 debugged. If provided, only the exceptions whose names match REGEXP
98 set debug symfile off|on
100 Control display of debugging info regarding reading symbol files and
101 symbol tables within those files
103 set print raw frame-arguments
104 show print raw frame-arguments
105 Set/show whether to print frame arguments in raw mode,
106 disregarding any defined pretty-printers.
108 set remote trace-status-packet
109 show remote trace-status-packet
110 Set/show the use of remote protocol qTStatus packet.
114 Control display of debugging messages related to Nios II targets.
118 Control whether target-assisted range stepping is enabled.
120 set startup-with-shell
121 show startup-with-shell
122 Specifies whether Unix child processes are started via a shell or
127 Use the target memory cache for accesses to the code segment. This
128 improves performance of remote debugging (particularly disassembly).
130 * You can now use a literal value 'unlimited' for options that
131 interpret 0 or -1 as meaning "unlimited". E.g., "set
132 trace-buffer-size unlimited" is now an alias for "set
133 trace-buffer-size -1" and "set height unlimited" is now an alias for
136 * The "set debug symtab-create" debugging option of GDB has been changed to
137 accept a verbosity level. 0 means "off", 1 provides basic debugging
138 output, and values of 2 or greater provides more verbose output.
140 * New command-line options
142 Display the details of GDB configure-time options.
144 * The command 'tsave' can now support new option '-ctf' to save trace
145 buffer in Common Trace Format.
147 * Newly installed $prefix/bin/gcore acts as a shell interface for the
150 * GDB now implements the the C++ 'typeid' operator.
152 * The new convenience variable $_exception holds the exception being
153 thrown or caught at an exception-related catchpoint.
155 * The exception-related catchpoints, like "catch throw", now accept a
156 regular expression which can be used to filter exceptions by type.
158 * The new convenience variable $_exitsignal is automatically set to
159 the terminating signal number when the program being debugged dies
160 due to an uncaught signal.
164 ** All MI commands now accept an optional "--language" option.
165 Support for this feature can be verified by using the "-list-features"
166 command, which should contain "language-option".
168 ** The new command -info-gdb-mi-command allows the user to determine
169 whether a GDB/MI command is supported or not.
171 ** The "^error" result record returned when trying to execute an undefined
172 GDB/MI command now provides a variable named "code" whose content is the
173 "undefined-command" error code. Support for this feature can be verified
174 by using the "-list-features" command, which should contain
175 "undefined-command-error-code".
177 ** The -trace-save MI command can optionally save trace buffer in Common
180 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
182 ** The command -data-list-register-values now accepts an optional
183 "--skip-unavailable" option. When used, only the available registers
186 ** The new command -trace-frame-collected dumps collected variables,
187 computed expressions, tvars, memory and registers in a traceframe.
189 ** The commands -stack-list-locals, -stack-list-arguments and
190 -stack-list-variables now accept an option "--skip-unavailable".
191 When used, only the available locals or arguments are displayed.
193 ** The -exec-run command now accepts an optional "--start" option.
194 When used, the command follows the same semantics as the "start"
195 command, stopping the program's execution at the start of its
196 main subprogram. Support for this feature can be verified using
197 the "-list-features" command, which should contain
198 "exec-run-start-option".
200 ** The new commands -catch-assert and -catch-exceptions insert
201 catchpoints stopping the program when Ada exceptions are raised.
203 ** The new command -info-ada-exceptions provides the equivalent of
204 the new "info exceptions" command.
206 * New system-wide configuration scripts
207 A GDB installation now provides scripts suitable for use as system-wide
208 configuration scripts for the following systems:
212 * GDB now supports target-assigned range stepping with remote targets.
213 This improves the performance of stepping source lines by reducing
214 the number of control packets from/to GDB. See "New remote packets"
217 * GDB now understands the element 'tvar' in the XML traceframe info.
218 It has the id of the collected trace state variables.
220 * On S/390 targets that provide the transactional-execution feature,
221 the program interruption transaction diagnostic block (TDB) is now
222 represented as a number of additional "registers" in GDB.
228 The vCont packet supports a new 'r' action, that tells the remote
229 stub to step through an address range itself, without GDB
230 involvemement at each single-step.
232 qXfer:libraries-svr4:read's annex
233 The previously unused annex of the qXfer:libraries-svr4:read packet
234 is now used to support passing an argument list. The remote stub
235 reports support for this argument list to GDB's qSupported query.
236 The defined arguments are "start" and "prev", used to reduce work
237 necessary for library list updating, resulting in significant
240 * New features in the GDB remote stub, GDBserver
242 ** GDBserver now supports target-assisted range stepping. Currently
243 enabled on x86/x86_64 GNU/Linux targets.
245 ** GDBserver now adds element 'tvar' in the XML in the reply to
246 'qXfer:traceframe-info:read'. It has the id of the collected
247 trace state variables.
249 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
252 * New 'z' formatter for printing and examining memory, this displays the
253 value as hexadecimal zero padded on the left to the size of the type.
255 * GDB can now use Windows x64 unwinding data.
257 * The "set remotebaud" command has been replaced by "set serial baud".
258 Similarly, "show remotebaud" has been replaced by "show serial baud".
259 The "set remotebaud" and "show remotebaud" commands are still available
260 to provide backward compatibility with older versions of GDB.
262 *** Changes in GDB 7.6
264 * Target record has been renamed to record-full.
265 Record/replay is now enabled with the "record full" command.
266 This also affects settings that are associated with full record/replay
267 that have been moved from "set/show record" to "set/show record full":
269 set|show record full insn-number-max
270 set|show record full stop-at-limit
271 set|show record full memory-query
273 * A new record target "record-btrace" has been added. The new target
274 uses hardware support to record the control-flow of a process. It
275 does not support replaying the execution, but it implements the
276 below new commands for investigating the recorded execution log.
277 This new recording method can be enabled using:
281 The "record-btrace" target is only available on Intel Atom processors
282 and requires a Linux kernel 2.6.32 or later.
284 * Two new commands have been added for record/replay to give information
285 about the recorded execution without having to replay the execution.
286 The commands are only supported by "record btrace".
288 record instruction-history prints the execution history at
289 instruction granularity
291 record function-call-history prints the execution history at
294 * New native configurations
296 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
297 FreeBSD/powerpc powerpc*-*-freebsd
298 x86_64/Cygwin x86_64-*-cygwin*
299 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
303 ARM AArch64 aarch64*-*-elf
304 ARM AArch64 GNU/Linux aarch64*-*-linux
305 Lynx 178 PowerPC powerpc-*-lynx*178
306 x86_64/Cygwin x86_64-*-cygwin*
307 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
309 * If the configured location of system.gdbinit file (as given by the
310 --with-system-gdbinit option at configure time) is in the
311 data-directory (as specified by --with-gdb-datadir at configure
312 time) or in one of its subdirectories, then GDB will look for the
313 system-wide init file in the directory specified by the
314 --data-directory command-line option.
316 * New command line options:
318 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
319 other initialization files, unlike -nx which disables all of them.
321 * Removed command line options
323 -epoch This was used by the gdb mode in Epoch, an ancient fork of
326 * The 'ptype' and 'whatis' commands now accept an argument to control
329 * 'info proc' now works on some core files.
333 ** Vectors can be created with gdb.Type.vector.
335 ** Python's atexit.register now works in GDB.
337 ** Types can be pretty-printed via a Python API.
339 ** Python 3 is now supported (in addition to Python 2.4 or later)
341 ** New class gdb.Architecture exposes GDB's internal representation
342 of architecture in the Python API.
344 ** New method Frame.architecture returns the gdb.Architecture object
345 corresponding to the frame's architecture.
347 * New Python-based convenience functions:
349 ** $_memeq(buf1, buf2, length)
350 ** $_streq(str1, str2)
352 ** $_regex(str, regex)
354 * The 'cd' command now defaults to using '~' (the home directory) if not
357 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
358 default for GCC since November 2000.
360 * The command 'forward-search' can now be abbreviated as 'fo'.
362 * The command 'info tracepoints' can now display 'installed on target'
363 or 'not installed on target' for each non-pending location of tracepoint.
365 * New configure options
367 --enable-libmcheck/--disable-libmcheck
368 By default, development versions are built with -lmcheck on hosts
369 that support it, in order to help track memory corruption issues.
370 Release versions, on the other hand, are built without -lmcheck
371 by default. The --enable-libmcheck/--disable-libmcheck configure
372 options allow the user to override that default.
373 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
374 This configure option allows the user to build GDB with
375 libbabeltrace using which GDB can read Common Trace Format data.
377 * New commands (for set/show, see "New options" below)
380 Catch signals. This is similar to "handle", but allows commands and
381 conditions to be attached.
384 List the BFDs known to GDB.
386 python-interactive [command]
388 Start a Python interactive prompt, or evaluate the optional command
389 and print the result of expressions.
392 "py" is a new alias for "python".
394 enable type-printer [name]...
395 disable type-printer [name]...
396 Enable or disable type printers.
400 ** For the Renesas Super-H architecture, the "regs" command has been removed
401 (has been deprecated in GDB 7.5), and "info all-registers" should be used
406 set print type methods (on|off)
407 show print type methods
408 Control whether method declarations are displayed by "ptype".
409 The default is to show them.
411 set print type typedefs (on|off)
412 show print type typedefs
413 Control whether typedef definitions are displayed by "ptype".
414 The default is to show them.
416 set filename-display basename|relative|absolute
417 show filename-display
418 Control the way in which filenames is displayed.
419 The default is "relative", which preserves previous behavior.
421 set trace-buffer-size
422 show trace-buffer-size
423 Request target to change the size of trace buffer.
425 set remote trace-buffer-size-packet auto|on|off
426 show remote trace-buffer-size-packet
427 Control the use of the remote protocol `QTBuffer:size' packet.
431 Control display of debugging messages related to ARM AArch64.
434 set debug coff-pe-read
435 show debug coff-pe-read
436 Control display of debugging messages related to reading of COFF/PE
441 Control display of debugging messages related to Mach-O symbols
444 set debug notification
445 show debug notification
446 Control display of debugging info for async remote notification.
450 ** Command parameter changes are now notified using new async record
451 "=cmd-param-changed".
452 ** Trace frame changes caused by command "tfind" are now notified using
453 new async record "=traceframe-changed".
454 ** The creation, deletion and modification of trace state variables
455 are now notified using new async records "=tsv-created",
456 "=tsv-deleted" and "=tsv-modified".
457 ** The start and stop of process record are now notified using new
458 async record "=record-started" and "=record-stopped".
459 ** Memory changes are now notified using new async record
461 ** The data-disassemble command response will include a "fullname" field
462 containing the absolute file name when source has been requested.
463 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
464 command, to allow pattern filling of memory areas.
465 ** New commands "-catch-load"/"-catch-unload" added for intercepting
466 library load/unload events.
467 ** The response to breakpoint commands and breakpoint async records
468 includes an "installed" field containing a boolean state about each
469 non-pending tracepoint location is whether installed on target or not.
470 ** Output of the "-trace-status" command includes a "trace-file" field
471 containing the name of the trace file being examined. This field is
472 optional, and only present when examining a trace file.
473 ** The "fullname" field is now always present along with the "file" field,
474 even if the file cannot be found by GDB.
476 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
477 You must have the LZMA library available when configuring GDB for this
478 feature to be enabled. For more information, see:
479 http://fedoraproject.org/wiki/Features/MiniDebugInfo
484 Set the size of trace buffer. The remote stub reports support for this
485 packet to gdb's qSupported query.
488 Enable Branch Trace Store (BTS)-based branch tracing for the current
489 thread. The remote stub reports support for this packet to gdb's
493 Disable branch tracing for the current thread. The remote stub reports
494 support for this packet to gdb's qSupported query.
497 Read the traced branches for the current thread. The remote stub
498 reports support for this packet to gdb's qSupported query.
500 *** Changes in GDB 7.5
502 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
503 for more x32 ABI info.
505 * GDB now supports access to MIPS DSP registers on Linux targets.
507 * GDB now supports debugging microMIPS binaries.
509 * The "info os" command on GNU/Linux can now display information on
510 several new classes of objects managed by the operating system:
511 "info os procgroups" lists process groups
512 "info os files" lists file descriptors
513 "info os sockets" lists internet-domain sockets
514 "info os shm" lists shared-memory regions
515 "info os semaphores" lists semaphores
516 "info os msg" lists message queues
517 "info os modules" lists loaded kernel modules
519 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
520 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
521 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
522 options and inspect the probe arguments using the new $_probe_arg family
523 of convenience variables. You can obtain more information about SystemTap
524 in <http://sourceware.org/systemtap/>.
526 * GDB now supports reversible debugging on ARM, it allows you to
527 debug basic ARM and THUMB instructions, and provides
528 record/replay support.
530 * The option "symbol-reloading" has been deleted as it is no longer used.
534 ** GDB commands implemented in Python can now be put in command class
537 ** The "maint set python print-stack on|off" is now deleted.
539 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
540 apply "flag enum"-style pretty-printing to any enum.
542 ** gdb.lookup_symbol can now work when there is no current frame.
544 ** gdb.Symbol now has a 'line' attribute, holding the line number in
545 the source at which the symbol was defined.
547 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
548 method 'value'. The former indicates whether the symbol needs a
549 frame in order to compute its value, and the latter computes the
552 ** A new method 'referenced_value' on gdb.Value objects which can
553 dereference pointer as well as C++ reference values.
555 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
556 which return the global and static blocks (as gdb.Block objects),
557 of the underlying symbol table, respectively.
559 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
560 object associated with a PC value.
562 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
563 of the address range occupied by code for the current source line.
565 * Go language support.
566 GDB now supports debugging programs written in the Go programming
569 * GDBserver now supports stdio connections.
570 E.g. (gdb) target remote | ssh myhost gdbserver - hello
572 * The binary "gdbtui" can no longer be built or installed.
573 Use "gdb -tui" instead.
575 * GDB will now print "flag" enums specially. A flag enum is one where
576 all the enumerator values have no bits in common when pairwise
577 "and"ed. When printing a value whose type is a flag enum, GDB will
578 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
579 (gdb) print (enum E) 3
582 * The filename part of a linespec will now match trailing components
583 of a source file name. For example, "break gcc/expr.c:1000" will
584 now set a breakpoint in build/gcc/expr.c, but not
587 * The "info proc" and "generate-core-file" commands will now also
588 work on remote targets connected to GDBserver on Linux.
590 * The command "info catch" has been removed. It has been disabled
593 * The "catch exception" and "catch assert" commands now accept
594 a condition at the end of the command, much like the "break"
595 command does. For instance:
597 (gdb) catch exception Constraint_Error if Barrier = True
599 Previously, it was possible to add a condition to such catchpoints,
600 but it had to be done as a second step, after the catchpoint had been
601 created, using the "condition" command.
603 * The "info static-tracepoint-marker" command will now also work on
604 native Linux targets with in-process agent.
606 * GDB can now set breakpoints on inlined functions.
608 * The .gdb_index section has been updated to include symbols for
609 inlined functions. GDB will ignore older .gdb_index sections by
610 default, which could cause symbol files to be loaded more slowly
611 until their .gdb_index sections can be recreated. The new command
612 "set use-deprecated-index-sections on" will cause GDB to use any older
613 .gdb_index sections it finds. This will restore performance, but the
614 ability to set breakpoints on inlined functions will be lost in symbol
615 files with older .gdb_index sections.
617 The .gdb_index section has also been updated to record more information
618 about each symbol. This speeds up the "info variables", "info functions"
619 and "info types" commands when used with programs having the .gdb_index
620 section, as well as speeding up debugging with shared libraries using
621 the .gdb_index section.
623 * Ada support for GDB/MI Variable Objects has been added.
625 * GDB can now support 'breakpoint always-inserted mode' in 'record'
630 ** New command -info-os is the MI equivalent of "info os".
632 ** Output logs ("set logging" and related) now include MI output.
636 ** "set use-deprecated-index-sections on|off"
637 "show use-deprecated-index-sections on|off"
638 Controls the use of deprecated .gdb_index sections.
640 ** "catch load" and "catch unload" can be used to stop when a shared
641 library is loaded or unloaded, respectively.
643 ** "enable count" can be used to auto-disable a breakpoint after
646 ** "info vtbl" can be used to show the virtual method tables for
647 C++ and Java objects.
649 ** "explore" and its sub commands "explore value" and "explore type"
650 can be used to recursively explore values and types of
651 expressions. These commands are available only if GDB is
652 configured with '--with-python'.
654 ** "info auto-load" shows status of all kinds of auto-loaded files,
655 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
656 sequences of commands files, "info auto-load python-scripts"
657 shows status of auto-loading Python script files,
658 "info auto-load local-gdbinit" shows status of loading init file
659 (.gdbinit) from current directory and "info auto-load libthread-db" shows
660 status of inferior specific thread debugging shared library loading.
662 ** "info auto-load-scripts", "set auto-load-scripts on|off"
663 and "show auto-load-scripts" commands have been deprecated, use their
664 "info auto-load python-scripts", "set auto-load python-scripts on|off"
665 and "show auto-load python-scripts" counterparts instead.
667 ** "dprintf location,format,args..." creates a dynamic printf, which
668 is basically a breakpoint that does a printf and immediately
669 resumes your program's execution, so it is like a printf that you
670 can insert dynamically at runtime instead of at compiletime.
672 ** "set print symbol"
674 Controls whether GDB attempts to display the symbol, if any,
675 corresponding to addresses it prints. This defaults to "on", but
676 you can set it to "off" to restore GDB's previous behavior.
678 * Deprecated commands
680 ** For the Renesas Super-H architecture, the "regs" command has been
681 deprecated, and "info all-registers" should be used instead.
685 Renesas RL78 rl78-*-elf
686 HP OpenVMS ia64 ia64-hp-openvms*
688 * GDBserver supports evaluation of breakpoint conditions. When
689 support is advertised by GDBserver, GDB may be told to send the
690 breakpoint conditions in bytecode form to GDBserver. GDBserver
691 will only report the breakpoint trigger to GDB when its condition
697 show mips compression
698 Select the compressed ISA encoding used in functions that have no symbol
699 information available. The encoding can be set to either of:
702 and is updated automatically from ELF file flags if available.
704 set breakpoint condition-evaluation
705 show breakpoint condition-evaluation
706 Control whether breakpoint conditions are evaluated by GDB ("host") or by
707 GDBserver ("target"). Default option "auto" chooses the most efficient
709 This option can improve debugger efficiency depending on the speed of the
713 Disable auto-loading globally.
716 Show auto-loading setting of all kinds of auto-loaded files.
718 set auto-load gdb-scripts on|off
719 show auto-load gdb-scripts
720 Control auto-loading of GDB canned sequences of commands files.
722 set auto-load python-scripts on|off
723 show auto-load python-scripts
724 Control auto-loading of Python script files.
726 set auto-load local-gdbinit on|off
727 show auto-load local-gdbinit
728 Control loading of init file (.gdbinit) from current directory.
730 set auto-load libthread-db on|off
731 show auto-load libthread-db
732 Control auto-loading of inferior specific thread debugging shared library.
734 set auto-load scripts-directory <dir1>[:<dir2>...]
735 show auto-load scripts-directory
736 Set a list of directories from which to load auto-loaded scripts.
737 Automatically loaded Python scripts and GDB scripts are located in one
738 of the directories listed by this option.
739 The delimiter (':' above) may differ according to the host platform.
741 set auto-load safe-path <dir1>[:<dir2>...]
742 show auto-load safe-path
743 Set a list of directories from which it is safe to auto-load files.
744 The delimiter (':' above) may differ according to the host platform.
746 set debug auto-load on|off
748 Control display of debugging info for auto-loading the files above.
750 set dprintf-style gdb|call|agent
752 Control the way in which a dynamic printf is performed; "gdb"
753 requests a GDB printf command, while "call" causes dprintf to call a
754 function in the inferior. "agent" requests that the target agent
755 (such as GDBserver) do the printing.
757 set dprintf-function <expr>
758 show dprintf-function
759 set dprintf-channel <expr>
761 Set the function and optional first argument to the call when using
762 the "call" style of dynamic printf.
764 set disconnected-dprintf on|off
765 show disconnected-dprintf
766 Control whether agent-style dynamic printfs continue to be in effect
767 after GDB disconnects.
769 * New configure options
772 Configure default value for the 'set auto-load scripts-directory'
773 setting above. It defaults to '$debugdir:$datadir/auto-load',
774 $debugdir representing global debugging info directories (available
775 via 'show debug-file-directory') and $datadir representing GDB's data
776 directory (available via 'show data-directory').
778 --with-auto-load-safe-path
779 Configure default value for the 'set auto-load safe-path' setting
780 above. It defaults to the --with-auto-load-dir setting.
782 --without-auto-load-safe-path
783 Set 'set auto-load safe-path' to '/', effectively disabling this
788 z0/z1 conditional breakpoints extension
790 The z0/z1 breakpoint insertion packets have been extended to carry
791 a list of conditional expressions over to the remote stub depending on the
792 condition evaluation mode. The use of this extension can be controlled
793 via the "set remote conditional-breakpoints-packet" command.
797 Specify the signals which the remote stub may pass to the debugged
798 program without GDB involvement.
800 * New command line options
802 --init-command=FILE, -ix Like --command, -x but execute it
803 before loading inferior.
804 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
805 execute it before loading inferior.
807 *** Changes in GDB 7.4
809 * GDB now handles ambiguous linespecs more consistently; the existing
810 FILE:LINE support has been expanded to other types of linespecs. A
811 breakpoint will now be set on all matching locations in all
812 inferiors, and locations will be added or removed according to
815 * GDB now allows you to skip uninteresting functions and files when
816 stepping with the "skip function" and "skip file" commands.
818 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
819 and "show remote hardware-watchpoint-length-limit". These allows to
820 set or show the maximum length limit (in bytes) of a remote
821 target hardware watchpoint.
823 This allows e.g. to use "unlimited" hardware watchpoints with the
824 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
825 watchpoints are slower than real hardware watchpoints but are
826 significantly faster than gdb software watchpoints.
830 ** The register_pretty_printer function in module gdb.printing now takes
831 an optional `replace' argument. If True, the new printer replaces any
834 ** The "maint set python print-stack on|off" command has been
835 deprecated and will be deleted in GDB 7.5.
836 A new command: "set python print-stack none|full|message" has
837 replaced it. Additionally, the default for "print-stack" is
838 now "message", which just prints the error message without
841 ** A prompt substitution hook (prompt_hook) is now available to the
844 ** A new Python module, gdb.prompt has been added to the GDB Python
845 modules library. This module provides functionality for
846 escape sequences in prompts (used by set/show
847 extended-prompt). These escape sequences are replaced by their
850 ** Python commands and convenience-functions located in
851 'data-directory'/python/gdb/command and
852 'data-directory'/python/gdb/function are now automatically loaded
855 ** Blocks now provide four new attributes. global_block and
856 static_block will return the global and static blocks
857 respectively. is_static and is_global are boolean attributes
858 that indicate if the block is one of those two types.
860 ** Symbols now provide the "type" attribute, the type of the symbol.
862 ** The "gdb.breakpoint" function has been deprecated in favor of
865 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
866 of a function. This class is based on the "finish" command
867 available in the CLI.
869 ** Type objects for struct and union types now allow access to
870 the fields using standard Python dictionary (mapping) methods.
871 For example, "some_type['myfield']" now works, as does
874 ** A new event "gdb.new_objfile" has been added, triggered by loading a
877 ** A new function, "deep_items" has been added to the gdb.types
878 module in the GDB Python modules library. This function returns
879 an iterator over the fields of a struct or union type. Unlike
880 the standard Python "iteritems" method, it will recursively traverse
881 any anonymous fields.
885 ** "*stopped" events can report several new "reason"s, such as
888 ** Breakpoint changes are now notified using new async records, like
889 "=breakpoint-modified".
891 ** New command -ada-task-info.
893 * libthread-db-search-path now supports two special values: $sdir and $pdir.
894 $sdir specifies the default system locations of shared libraries.
895 $pdir specifies the directory where the libpthread used by the application
898 GDB no longer looks in $sdir and $pdir after it has searched the directories
899 mentioned in libthread-db-search-path. If you want to search those
900 directories, they must be specified in libthread-db-search-path.
901 The default value of libthread-db-search-path on GNU/Linux and Solaris
902 systems is now "$sdir:$pdir".
904 $pdir is not supported by gdbserver, it is currently ignored.
905 $sdir is supported by gdbserver.
907 * New configure option --with-iconv-bin.
908 When using the internationalization support like the one in the GNU C
909 library, GDB will invoke the "iconv" program to get a list of supported
910 character sets. If this program lives in a non-standard location, one can
911 use this option to specify where to find it.
913 * When natively debugging programs on PowerPC BookE processors running
914 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
915 watchpoints, which specify a mask in addition to an address to watch.
916 The mask specifies that some bits of an address (the bits which are
917 reset in the mask) should be ignored when matching the address accessed
918 by the inferior against the watchpoint address. See the "PowerPC Embedded"
919 section in the user manual for more details.
921 * The new option --once causes GDBserver to stop listening for connections once
922 the first connection is made. The listening port used by GDBserver will
923 become available after that.
925 * New commands "info macros" and "alias" have been added.
927 * New function parameters suffix @entry specifies value of function parameter
928 at the time the function got called. Entry values are available only since
934 "!" is now an alias of the "shell" command.
935 Note that no space is needed between "!" and SHELL COMMAND.
939 watch EXPRESSION mask MASK_VALUE
940 The watch command now supports the mask argument which allows creation
941 of masked watchpoints, if the current architecture supports this feature.
943 info auto-load-scripts [REGEXP]
944 This command was formerly named "maintenance print section-scripts".
945 It is now generally useful and is no longer a maintenance-only command.
947 info macro [-all] [--] MACRO
948 The info macro command has new options `-all' and `--'. The first for
949 printing all definitions of a macro. The second for explicitly specifying
950 the end of arguments and the beginning of the macro name in case the macro
951 name starts with a hyphen.
953 collect[/s] EXPRESSIONS
954 The tracepoint collect command now takes an optional modifier "/s"
955 that directs it to dereference pointer-to-character types and
956 collect the bytes of memory up to a zero byte. The behavior is
957 similar to what you see when you use the regular print command on a
958 string. An optional integer following the "/s" sets a bound on the
959 number of bytes that will be collected.
962 The trace start command now interprets any supplied arguments as a
963 note to be recorded with the trace run, with an effect similar to
964 setting the variable trace-notes.
967 The trace stop command now interprets any arguments as a note to be
968 mentioned along with the tstatus report that the trace was stopped
969 with a command. The effect is similar to setting the variable
972 * Tracepoints can now be enabled and disabled at any time after a trace
973 experiment has been started using the standard "enable" and "disable"
974 commands. It is now possible to start a trace experiment with no enabled
975 tracepoints; GDB will display a warning, but will allow the experiment to
976 begin, assuming that tracepoints will be enabled as needed while the trace
979 * Fast tracepoints on 32-bit x86-architectures can now be placed at
980 locations with 4-byte instructions, when they were previously
981 limited to locations with instructions of 5 bytes or longer.
985 set debug dwarf2-read
986 show debug dwarf2-read
987 Turns on or off display of debugging messages related to reading
988 DWARF debug info. The default is off.
990 set debug symtab-create
991 show debug symtab-create
992 Turns on or off display of debugging messages related to symbol table
993 creation. The default is off.
997 Set the GDB prompt, and allow escape sequences to be inserted to
998 display miscellaneous information (see 'help set extended-prompt'
999 for the list of sequences). This prompt (and any information
1000 accessed through the escape sequences) is updated every time the
1001 prompt is displayed.
1003 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1004 show print entry-values
1005 Set printing of frame argument values at function entry. In some cases
1006 GDB can determine the value of function argument which was passed by the
1007 function caller, even if the value was modified inside the called function.
1009 set debug entry-values
1010 show debug entry-values
1011 Control display of debugging info for determining frame argument values at
1012 function entry and virtual tail call frames.
1014 set basenames-may-differ
1015 show basenames-may-differ
1016 Set whether a source file may have multiple base names.
1017 (A "base name" is the name of a file with the directory part removed.
1018 Example: The base name of "/home/user/hello.c" is "hello.c".)
1019 If set, GDB will canonicalize file names (e.g., expand symlinks)
1020 before comparing them. Canonicalization is an expensive operation,
1021 but it allows the same file be known by more than one base name.
1022 If not set (the default), all source files are assumed to have just
1023 one base name, and gdb will do file name comparisons more efficiently.
1029 Set a user name and notes for the current and any future trace runs.
1030 This is useful for long-running and/or disconnected traces, to
1031 inform others (or yourself) as to who is running the trace, supply
1032 contact information, or otherwise explain what is going on.
1034 set trace-stop-notes
1035 show trace-stop-notes
1036 Set a note attached to the trace run, that is displayed when the
1037 trace has been stopped by a tstop command. This is useful for
1038 instance as an explanation, if you are stopping a trace run that was
1039 started by someone else.
1041 * New remote packets
1045 Dynamically enable a tracepoint in a started trace experiment.
1049 Dynamically disable a tracepoint in a started trace experiment.
1053 Set the user and notes of the trace run.
1057 Query the current status of a tracepoint.
1061 Query the minimum length of instruction at which a fast tracepoint may
1064 * Dcache size (number of lines) and line-size are now runtime-configurable
1065 via "set dcache line" and "set dcache line-size" commands.
1069 Texas Instruments TMS320C6x tic6x-*-*
1073 Renesas RL78 rl78-*-elf
1075 *** Changes in GDB 7.3.1
1077 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1079 *** Changes in GDB 7.3
1081 * GDB has a new command: "thread find [REGEXP]".
1082 It finds the thread id whose name, target id, or thread extra info
1083 matches the given regular expression.
1085 * The "catch syscall" command now works on mips*-linux* targets.
1087 * The -data-disassemble MI command now supports modes 2 and 3 for
1088 dumping the instruction opcodes.
1090 * New command line options
1092 -data-directory DIR Specify DIR as the "data-directory".
1093 This is mostly for testing purposes.
1095 * The "maint set python auto-load on|off" command has been renamed to
1096 "set auto-load-scripts on|off".
1098 * GDB has a new command: "set directories".
1099 It is like the "dir" command except that it replaces the
1100 source path list instead of augmenting it.
1102 * GDB now understands thread names.
1104 On GNU/Linux, "info threads" will display the thread name as set by
1105 prctl or pthread_setname_np.
1107 There is also a new command, "thread name", which can be used to
1108 assign a name internally for GDB to display.
1111 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1112 has been integrated into GDB.
1116 ** The function gdb.Write now accepts an optional keyword 'stream'.
1117 This keyword, when provided, will direct the output to either
1118 stdout, stderr, or GDB's logging output.
1120 ** Parameters can now be be sub-classed in Python, and in particular
1121 you may implement the get_set_doc and get_show_doc functions.
1122 This improves how Parameter set/show documentation is processed
1123 and allows for more dynamic content.
1125 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1126 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1127 have an is_valid method.
1129 ** Breakpoints can now be sub-classed in Python, and in particular
1130 you may implement a 'stop' function that is executed each time
1131 the inferior reaches that breakpoint.
1133 ** New function gdb.lookup_global_symbol looks up a global symbol.
1135 ** GDB values in Python are now callable if the value represents a
1136 function. For example, if 'some_value' represents a function that
1137 takes two integer parameters and returns a value, you can call
1138 that function like so:
1140 result = some_value (10,20)
1142 ** Module gdb.types has been added.
1143 It contains a collection of utilities for working with gdb.Types objects:
1144 get_basic_type, has_field, make_enum_dict.
1146 ** Module gdb.printing has been added.
1147 It contains utilities for writing and registering pretty-printers.
1148 New classes: PrettyPrinter, SubPrettyPrinter,
1149 RegexpCollectionPrettyPrinter.
1150 New function: register_pretty_printer.
1152 ** New commands "info pretty-printers", "enable pretty-printer" and
1153 "disable pretty-printer" have been added.
1155 ** gdb.parameter("directories") is now available.
1157 ** New function gdb.newest_frame returns the newest frame in the
1160 ** The gdb.InferiorThread class has a new "name" attribute. This
1161 holds the thread's name.
1163 ** Python Support for Inferior events.
1164 Python scripts can add observers to be notified of events
1165 occurring in the process being debugged.
1166 The following events are currently supported:
1167 - gdb.events.cont Continue event.
1168 - gdb.events.exited Inferior exited event.
1169 - gdb.events.stop Signal received, and Breakpoint hit events.
1173 ** GDB now puts template parameters in scope when debugging in an
1174 instantiation. For example, if you have:
1176 template<int X> int func (void) { return X; }
1178 then if you step into func<5>, "print X" will show "5". This
1179 feature requires proper debuginfo support from the compiler; it
1180 was added to GCC 4.5.
1182 ** The motion commands "next", "finish", "until", and "advance" now
1183 work better when exceptions are thrown. In particular, GDB will
1184 no longer lose control of the inferior; instead, the GDB will
1185 stop the inferior at the point at which the exception is caught.
1186 This functionality requires a change in the exception handling
1187 code that was introduced in GCC 4.5.
1189 * GDB now follows GCC's rules on accessing volatile objects when
1190 reading or writing target state during expression evaluation.
1191 One notable difference to prior behavior is that "print x = 0"
1192 no longer generates a read of x; the value of the assignment is
1193 now always taken directly from the value being assigned.
1195 * GDB now has some support for using labels in the program's source in
1196 linespecs. For instance, you can use "advance label" to continue
1197 execution to a label.
1199 * GDB now has support for reading and writing a new .gdb_index
1200 section. This section holds a fast index of DWARF debugging
1201 information and can be used to greatly speed up GDB startup and
1202 operation. See the documentation for `save gdb-index' for details.
1204 * The "watch" command now accepts an optional "-location" argument.
1205 When used, this causes GDB to watch the memory referred to by the
1206 expression. Such a watchpoint is never deleted due to it going out
1209 * GDB now supports thread debugging of core dumps on GNU/Linux.
1211 GDB now activates thread debugging using the libthread_db library
1212 when debugging GNU/Linux core dumps, similarly to when debugging
1213 live processes. As a result, when debugging a core dump file, GDB
1214 is now able to display pthread_t ids of threads. For example, "info
1215 threads" shows the same output as when debugging the process when it
1216 was live. In earlier releases, you'd see something like this:
1219 * 1 LWP 6780 main () at main.c:10
1221 While now you see this:
1224 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1226 It is also now possible to inspect TLS variables when debugging core
1229 When debugging a core dump generated on a machine other than the one
1230 used to run GDB, you may need to point GDB at the correct
1231 libthread_db library with the "set libthread-db-search-path"
1232 command. See the user manual for more details on this command.
1234 * When natively debugging programs on PowerPC BookE processors running
1235 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1236 which stop execution of the inferior whenever it executes an instruction
1237 at any address within the specified range. See the "PowerPC Embedded"
1238 section in the user manual for more details.
1240 * New features in the GDB remote stub, GDBserver
1242 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1243 and i686 LynxOS (version 5.x).
1245 ** GDBserver is now supported on Blackfin Linux.
1247 * New native configurations
1249 ia64 HP-UX ia64-*-hpux*
1253 Analog Devices, Inc. Blackfin Processor bfin-*
1255 * Ada task switching is now supported on sparc-elf targets when
1256 debugging a program using the Ravenscar Profile. For more information,
1257 see the "Tasking Support when using the Ravenscar Profile" section
1258 in the GDB user manual.
1260 * Guile support was removed.
1262 * New features in the GNU simulator
1264 ** The --map-info flag lists all known core mappings.
1266 ** CFI flashes may be simulated via the "cfi" device.
1268 *** Changes in GDB 7.2
1270 * Shared library support for remote targets by default
1272 When GDB is configured for a generic, non-OS specific target, like
1273 for example, --target=arm-eabi or one of the many *-*-elf targets,
1274 GDB now queries remote stubs for loaded shared libraries using the
1275 `qXfer:libraries:read' packet. Previously, shared library support
1276 was always disabled for such configurations.
1280 ** Argument Dependent Lookup (ADL)
1282 In C++ ADL lookup directs function search to the namespaces of its
1283 arguments even if the namespace has not been imported.
1293 Here the compiler will search for `foo' in the namespace of 'b'
1294 and find A::foo. GDB now supports this. This construct is commonly
1295 used in the Standard Template Library for operators.
1297 ** Improved User Defined Operator Support
1299 In addition to member operators, GDB now supports lookup of operators
1300 defined in a namespace and imported with a `using' directive, operators
1301 defined in the global scope, operators imported implicitly from an
1302 anonymous namespace, and the ADL operators mentioned in the previous
1304 GDB now also supports proper overload resolution for all the previously
1305 mentioned flavors of operators.
1307 ** static const class members
1309 Printing of static const class members that are initialized in the
1310 class definition has been fixed.
1312 * Windows Thread Information Block access.
1314 On Windows targets, GDB now supports displaying the Windows Thread
1315 Information Block (TIB) structure. This structure is visible either
1316 by using the new command `info w32 thread-information-block' or, by
1317 dereferencing the new convenience variable named `$_tlb', a
1318 thread-specific pointer to the TIB. This feature is also supported
1319 when remote debugging using GDBserver.
1321 * Static tracepoints
1323 Static tracepoints are calls in the user program into a tracing
1324 library. One such library is a port of the LTTng kernel tracer to
1325 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1326 When debugging with GDBserver, GDB now supports combining the GDB
1327 tracepoint machinery with such libraries. For example: the user can
1328 use GDB to probe a static tracepoint marker (a call from the user
1329 program into the tracing library) with the new "strace" command (see
1330 "New commands" below). This creates a "static tracepoint" in the
1331 breakpoint list, that can be manipulated with the same feature set
1332 as fast and regular tracepoints. E.g., collect registers, local and
1333 global variables, collect trace state variables, and define
1334 tracepoint conditions. In addition, the user can collect extra
1335 static tracepoint marker specific data, by collecting the new
1336 $_sdata internal variable. When analyzing the trace buffer, you can
1337 inspect $_sdata like any other variable available to GDB. For more
1338 information, see the "Tracepoints" chapter in GDB user manual. New
1339 remote packets have been defined to support static tracepoints, see
1340 the "New remote packets" section below.
1342 * Better reconstruction of tracepoints after disconnected tracing
1344 GDB will attempt to download the original source form of tracepoint
1345 definitions when starting a trace run, and then will upload these
1346 upon reconnection to the target, resulting in a more accurate
1347 reconstruction of the tracepoints that are in use on the target.
1351 You can now exercise direct control over the ways that GDB can
1352 affect your program. For instance, you can disallow the setting of
1353 breakpoints, so that the program can run continuously (assuming
1354 non-stop mode). In addition, the "observer" variable is available
1355 to switch all of the different controls; in observer mode, GDB
1356 cannot affect the target's behavior at all, which is useful for
1357 tasks like diagnosing live systems in the field.
1359 * The new convenience variable $_thread holds the number of the
1362 * New remote packets
1366 Return the address of the Windows Thread Information Block of a given thread.
1370 In response to several of the tracepoint packets, the target may now
1371 also respond with a number of intermediate `qRelocInsn' request
1372 packets before the final result packet, to have GDB handle
1373 relocating an instruction to execute at a different address. This
1374 is particularly useful for stubs that support fast tracepoints. GDB
1375 reports support for this feature in the qSupported packet.
1379 List static tracepoint markers in the target program.
1383 List static tracepoint markers at a given address in the target
1386 qXfer:statictrace:read
1388 Read the static trace data collected (by a `collect $_sdata'
1389 tracepoint action). The remote stub reports support for this packet
1390 to gdb's qSupported query.
1394 Send the current settings of GDB's permission flags.
1398 Send part of the source (textual) form of a tracepoint definition,
1399 which includes location, conditional, and action list.
1401 * The source command now accepts a -s option to force searching for the
1402 script in the source search path even if the script name specifies
1405 * New features in the GDB remote stub, GDBserver
1407 - GDBserver now support tracepoints (including fast tracepoints, and
1408 static tracepoints). The feature is currently supported by the
1409 i386-linux and amd64-linux builds. See the "Tracepoints support
1410 in gdbserver" section in the manual for more information.
1412 GDBserver JIT compiles the tracepoint's conditional agent
1413 expression bytecode into native code whenever possible for low
1414 overhead dynamic tracepoints conditionals. For such tracepoints,
1415 an expression that examines program state is evaluated when the
1416 tracepoint is reached, in order to determine whether to capture
1417 trace data. If the condition is simple and false, processing the
1418 tracepoint finishes very quickly and no data is gathered.
1420 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1421 for static tracepoints support.
1423 - GDBserver now supports x86_64 Windows 64-bit debugging.
1425 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1426 it understands register description.
1428 * The --batch flag now disables pagination and queries.
1430 * X86 general purpose registers
1432 GDB now supports reading/writing byte, word and double-word x86
1433 general purpose registers directly. This means you can use, say,
1434 $ah or $ax to refer, respectively, to the byte register AH and
1435 16-bit word register AX that are actually portions of the 32-bit
1436 register EAX or 64-bit register RAX.
1438 * The `commands' command now accepts a range of breakpoints to modify.
1439 A plain `commands' following a command that creates multiple
1440 breakpoints affects all the breakpoints set by that command. This
1441 applies to breakpoints set by `rbreak', and also applies when a
1442 single `break' command creates multiple breakpoints (e.g.,
1443 breakpoints on overloaded c++ functions).
1445 * The `rbreak' command now accepts a filename specification as part of
1446 its argument, limiting the functions selected by the regex to those
1447 in the specified file.
1449 * Support for remote debugging Windows and SymbianOS shared libraries
1450 from Unix hosts has been improved. Non Windows GDB builds now can
1451 understand target reported file names that follow MS-DOS based file
1452 system semantics, such as file names that include drive letters and
1453 use the backslash character as directory separator. This makes it
1454 possible to transparently use the "set sysroot" and "set
1455 solib-search-path" on Unix hosts to point as host copies of the
1456 target's shared libraries. See the new command "set
1457 target-file-system-kind" described below, and the "Commands to
1458 specify files" section in the user manual for more information.
1462 eval template, expressions...
1463 Convert the values of one or more expressions under the control
1464 of the string template to a command line, and call it.
1466 set target-file-system-kind unix|dos-based|auto
1467 show target-file-system-kind
1468 Set or show the assumed file system kind for target reported file
1471 save breakpoints <filename>
1472 Save all current breakpoint definitions to a file suitable for use
1473 in a later debugging session. To read the saved breakpoint
1474 definitions, use the `source' command.
1476 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1479 info static-tracepoint-markers
1480 Display information about static tracepoint markers in the target.
1482 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1483 Define a static tracepoint by probing a marker at the given
1484 function, line, address, or marker ID.
1488 Enable and disable observer mode.
1490 set may-write-registers on|off
1491 set may-write-memory on|off
1492 set may-insert-breakpoints on|off
1493 set may-insert-tracepoints on|off
1494 set may-insert-fast-tracepoints on|off
1495 set may-interrupt on|off
1496 Set individual permissions for GDB effects on the target. Note that
1497 some of these settings can have undesirable or surprising
1498 consequences, particularly when changed in the middle of a session.
1499 For instance, disabling the writing of memory can prevent
1500 breakpoints from being inserted, cause single-stepping to fail, or
1501 even crash your program, if you disable after breakpoints have been
1502 inserted. However, GDB should not crash.
1504 set record memory-query on|off
1505 show record memory-query
1506 Control whether to stop the inferior if memory changes caused
1507 by an instruction cannot be recorded.
1512 The disassemble command now supports "start,+length" form of two arguments.
1516 ** GDB now provides a new directory location, called the python directory,
1517 where Python scripts written for GDB can be installed. The location
1518 of that directory is <data-directory>/python, where <data-directory>
1519 is the GDB data directory. For more details, see section `Scripting
1520 GDB using Python' in the manual.
1522 ** The GDB Python API now has access to breakpoints, symbols, symbol
1523 tables, program spaces, inferiors, threads and frame's code blocks.
1524 Additionally, GDB Parameters can now be created from the API, and
1525 manipulated via set/show in the CLI.
1527 ** New functions gdb.target_charset, gdb.target_wide_charset,
1528 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1530 ** New exception gdb.GdbError.
1532 ** Pretty-printers are now also looked up in the current program space.
1534 ** Pretty-printers can now be individually enabled and disabled.
1536 ** GDB now looks for names of Python scripts to auto-load in a
1537 special section named `.debug_gdb_scripts', in addition to looking
1538 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1540 * Tracepoint actions were unified with breakpoint commands. In particular,
1541 there are no longer differences in "info break" output for breakpoints and
1542 tracepoints and the "commands" command can be used for both tracepoints and
1543 regular breakpoints.
1547 ARM Symbian arm*-*-symbianelf*
1549 * D language support.
1550 GDB now supports debugging programs written in the D programming
1553 * GDB now supports the extended ptrace interface for PowerPC which is
1554 available since Linux kernel version 2.6.34. This automatically enables
1555 any hardware breakpoints and additional hardware watchpoints available in
1556 the processor. The old ptrace interface exposes just one hardware
1557 watchpoint and no hardware breakpoints.
1559 * GDB is now able to use the Data Value Compare (DVC) register available on
1560 embedded PowerPC processors to implement in hardware simple watchpoint
1561 conditions of the form:
1563 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1565 This works in native GDB running on Linux kernels with the extended ptrace
1566 interface mentioned above.
1568 *** Changes in GDB 7.1
1572 ** Namespace Support
1574 GDB now supports importing of namespaces in C++. This enables the
1575 user to inspect variables from imported namespaces. Support for
1576 namepace aliasing has also been added. So, if a namespace is
1577 aliased in the current scope (e.g. namepace C=A; ) the user can
1578 print variables using the alias (e.g. (gdb) print C::x).
1582 All known bugs relating to the printing of virtual base class were
1583 fixed. It is now possible to call overloaded static methods using a
1588 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1589 and reinterpret_cast<> are now handled by the C++ expression parser.
1593 Xilinx MicroBlaze microblaze-*-*
1598 Xilinx MicroBlaze microblaze
1601 * Multi-program debugging.
1603 GDB now has support for multi-program (a.k.a. multi-executable or
1604 multi-exec) debugging. This allows for debugging multiple inferiors
1605 simultaneously each running a different program under the same GDB
1606 session. See "Debugging Multiple Inferiors and Programs" in the
1607 manual for more information. This implied some user visible changes
1608 in the multi-inferior support. For example, "info inferiors" now
1609 lists inferiors that are not running yet or that have exited
1610 already. See also "New commands" and "New options" below.
1612 * New tracing features
1614 GDB's tracepoint facility now includes several new features:
1616 ** Trace state variables
1618 GDB tracepoints now include support for trace state variables, which
1619 are variables managed by the target agent during a tracing
1620 experiment. They are useful for tracepoints that trigger each
1621 other, so for instance one tracepoint can count hits in a variable,
1622 and then a second tracepoint has a condition that is true when the
1623 count reaches a particular value. Trace state variables share the
1624 $-syntax of GDB convenience variables, and can appear in both
1625 tracepoint actions and condition expressions. Use the "tvariable"
1626 command to create, and "info tvariables" to view; see "Trace State
1627 Variables" in the manual for more detail.
1631 GDB now includes an option for defining fast tracepoints, which
1632 targets may implement more efficiently, such as by installing a jump
1633 into the target agent rather than a trap instruction. The resulting
1634 speedup can be by two orders of magnitude or more, although the
1635 tradeoff is that some program locations on some target architectures
1636 might not allow fast tracepoint installation, for instance if the
1637 instruction to be replaced is shorter than the jump. To request a
1638 fast tracepoint, use the "ftrace" command, with syntax identical to
1639 the regular trace command.
1641 ** Disconnected tracing
1643 It is now possible to detach GDB from the target while it is running
1644 a trace experiment, then reconnect later to see how the experiment
1645 is going. In addition, a new variable disconnected-tracing lets you
1646 tell the target agent whether to continue running a trace if the
1647 connection is lost unexpectedly.
1651 GDB now has the ability to save the trace buffer into a file, and
1652 then use that file as a target, similarly to you can do with
1653 corefiles. You can select trace frames, print data that was
1654 collected in them, and use tstatus to display the state of the
1655 tracing run at the moment that it was saved. To create a trace
1656 file, use "tsave <filename>", and to use it, do "target tfile
1659 ** Circular trace buffer
1661 You can ask the target agent to handle the trace buffer as a
1662 circular buffer, discarding the oldest trace frames to make room for
1663 newer ones, by setting circular-trace-buffer to on. This feature may
1664 not be available for all target agents.
1669 The disassemble command, when invoked with two arguments, now requires
1670 the arguments to be comma-separated.
1673 The info variables command now displays variable definitions. Files
1674 which only declare a variable are not shown.
1677 The source command is now capable of sourcing Python scripts.
1678 This feature is dependent on the debugger being build with Python
1681 Related to this enhancement is also the introduction of a new command
1682 "set script-extension" (see below).
1684 * New commands (for set/show, see "New options" below)
1686 record save [<FILENAME>]
1687 Save a file (in core file format) containing the process record
1688 execution log for replay debugging at a later time.
1690 record restore <FILENAME>
1691 Restore the process record execution log that was saved at an
1692 earlier time, for replay debugging.
1694 add-inferior [-copies <N>] [-exec <FILENAME>]
1697 clone-inferior [-copies <N>] [ID]
1698 Make a new inferior ready to execute the same program another
1699 inferior has loaded.
1704 maint info program-spaces
1705 List the program spaces loaded into GDB.
1707 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1708 show remote interrupt-sequence
1709 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1710 as the sequence to the remote target in order to interrupt the execution.
1711 Ctrl-C is a default. Some system prefers BREAK which is high level of
1712 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1713 Magic SysRq g. It is BREAK signal and character 'g'.
1715 set remote interrupt-on-connect [on | off]
1716 show remote interrupt-on-connect
1717 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1718 remote target when gdb connects to it. This is needed when you debug
1721 set remotebreak [on | off]
1723 Deprecated. Use "set/show remote interrupt-sequence" instead.
1725 tvariable $NAME [ = EXP ]
1726 Create or modify a trace state variable.
1729 List trace state variables and their values.
1731 delete tvariable $NAME ...
1732 Delete one or more trace state variables.
1735 Evaluate the given expressions without collecting anything into the
1736 trace buffer. (Valid in tracepoint actions only.)
1738 ftrace FN / FILE:LINE / *ADDR
1739 Define a fast tracepoint at the given function, line, or address.
1741 * New expression syntax
1743 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1744 GDB now parses 0b101010 identically with 42.
1748 set follow-exec-mode new|same
1749 show follow-exec-mode
1750 Control whether GDB reuses the same inferior across an exec call or
1751 creates a new one. This is useful to be able to restart the old
1752 executable after the inferior having done an exec call.
1754 set default-collect EXPR, ...
1755 show default-collect
1756 Define a list of expressions to be collected at each tracepoint.
1757 This is a useful way to ensure essential items are not overlooked,
1758 such as registers or a critical global variable.
1760 set disconnected-tracing
1761 show disconnected-tracing
1762 If set to 1, the target is instructed to continue tracing if it
1763 loses its connection to GDB. If 0, the target is to stop tracing
1766 set circular-trace-buffer
1767 show circular-trace-buffer
1768 If set to on, the target is instructed to use a circular trace buffer
1769 and discard the oldest trace frames instead of stopping the trace due
1770 to a full trace buffer. If set to off, the trace stops when the buffer
1771 fills up. Some targets may not support this.
1773 set script-extension off|soft|strict
1774 show script-extension
1775 If set to "off", the debugger does not perform any script language
1776 recognition, and all sourced files are assumed to be GDB scripts.
1777 If set to "soft" (the default), files are sourced according to
1778 filename extension, falling back to GDB scripts if the first
1780 If set to "strict", files are sourced according to filename extension.
1782 set ada trust-PAD-over-XVS on|off
1783 show ada trust-PAD-over-XVS
1784 If off, activate a workaround against a bug in the debugging information
1785 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1786 the GCC sources for more information about the GNAT encoding and
1787 PAD types in particular). It is always safe to set this option to
1788 off, but this introduces a slight performance penalty. The default
1791 * Python API Improvements
1793 ** GDB provides the new class gdb.LazyString. This is useful in
1794 some pretty-printing cases. The new method gdb.Value.lazy_string
1795 provides a simple way to create objects of this type.
1797 ** The fields returned by gdb.Type.fields now have an
1798 `is_base_class' attribute.
1800 ** The new method gdb.Type.range returns the range of an array type.
1802 ** The new method gdb.parse_and_eval can be used to parse and
1803 evaluate an expression.
1805 * New remote packets
1808 Define a trace state variable.
1811 Get the current value of a trace state variable.
1814 Set desired tracing behavior upon disconnection.
1817 Set the trace buffer to be linear or circular.
1820 Get data about the tracepoints currently in use.
1824 Process record now works correctly with hardware watchpoints.
1826 Multiple bug fixes have been made to the mips-irix port, making it
1827 much more reliable. In particular:
1828 - Debugging threaded applications is now possible again. Previously,
1829 GDB would hang while starting the program, or while waiting for
1830 the program to stop at a breakpoint.
1831 - Attaching to a running process no longer hangs.
1832 - An error occurring while loading a core file has been fixed.
1833 - Changing the value of the PC register now works again. This fixes
1834 problems observed when using the "jump" command, or when calling
1835 a function from GDB, or even when assigning a new value to $pc.
1836 - With the "finish" and "return" commands, the return value for functions
1837 returning a small array is now correctly printed.
1838 - It is now possible to break on shared library code which gets executed
1839 during a shared library init phase (code executed while executing
1840 their .init section). Previously, the breakpoint would have no effect.
1841 - GDB is now able to backtrace through the signal handler for
1842 non-threaded programs.
1844 PIE (Position Independent Executable) programs debugging is now supported.
1845 This includes debugging execution of PIC (Position Independent Code) shared
1846 libraries although for that, it should be possible to run such libraries as an
1849 *** Changes in GDB 7.0
1851 * GDB now has an interface for JIT compilation. Applications that
1852 dynamically generate code can create symbol files in memory and register
1853 them with GDB. For users, the feature should work transparently, and
1854 for JIT developers, the interface is documented in the GDB manual in the
1855 "JIT Compilation Interface" chapter.
1857 * Tracepoints may now be conditional. The syntax is as for
1858 breakpoints; either an "if" clause appended to the "trace" command,
1859 or the "condition" command is available. GDB sends the condition to
1860 the target for evaluation using the same bytecode format as is used
1861 for tracepoint actions.
1863 * The disassemble command now supports: an optional /r modifier, print the
1864 raw instructions in hex as well as in symbolic form, and an optional /m
1865 modifier to print mixed source+assembly.
1867 * Process record and replay
1869 In a architecture environment that supports ``process record and
1870 replay'', ``process record and replay'' target can record a log of
1871 the process execution, and replay it with both forward and reverse
1874 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1875 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1876 set execution-direction {forward|reverse}, for targets that support
1879 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1880 feature is available with a native GDB running on kernel version
1883 * GDB now has support for multi-byte and wide character sets on the
1884 target. Strings whose character type is wchar_t, char16_t, or
1885 char32_t are now correctly printed. GDB supports wide- and unicode-
1886 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1887 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1888 `printf'. This feature requires iconv to work properly; if your
1889 system does not have a working iconv, GDB can use GNU libiconv. See
1890 the installation instructions for more information.
1892 * GDB now supports automatic retrieval of shared library files from
1893 remote targets. To use this feature, specify a system root that begins
1894 with the `remote:' prefix, either via the `set sysroot' command or via
1895 the `--with-sysroot' configure-time option.
1897 * "info sharedlibrary" now takes an optional regex of libraries to show,
1898 and it now reports if a shared library has no debugging information.
1900 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1901 now complete on file names.
1903 * When completing in expressions, gdb will attempt to limit
1904 completions to allowable structure or union fields, where appropriate.
1905 For instance, consider:
1907 # struct example { int f1; double f2; };
1908 # struct example variable;
1911 If the user types TAB at the end of this command line, the available
1912 completions will be "f1" and "f2".
1914 * Inlined functions are now supported. They show up in backtraces, and
1915 the "step", "next", and "finish" commands handle them automatically.
1917 * GDB now supports the token-splicing (##) and stringification (#)
1918 operators when expanding macros. It also supports variable-arity
1921 * GDB now supports inspecting extra signal information, exported by
1922 the new $_siginfo convenience variable. The feature is currently
1923 implemented on linux ARM, i386 and amd64.
1925 * GDB can now display the VFP floating point registers and NEON vector
1926 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1927 can provide these registers (requires Linux 2.6.30 or later). Remote
1928 and simulator targets may also provide them.
1930 * New remote packets
1933 Search memory for a sequence of bytes.
1936 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1937 operation over reliable transport links. Use of this packet is
1938 controlled by the `set remote noack-packet' command.
1941 Kill the process with the specified process ID. Use this in preference
1942 to `k' when multiprocess protocol extensions are supported.
1945 Obtains additional operating system information
1949 Read or write additional signal information.
1951 * Removed remote protocol undocumented extension
1953 An undocumented extension to the remote protocol's `S' stop reply
1954 packet that permited the stub to pass a process id was removed.
1955 Remote servers should use the `T' stop reply packet instead.
1957 * GDB now supports multiple function calling conventions according to the
1958 DWARF-2 DW_AT_calling_convention function attribute.
1960 * The SH target utilizes the aforementioned change to distinguish between gcc
1961 and Renesas calling convention. It also adds the new CLI commands
1962 `set/show sh calling-convention'.
1964 * GDB can now read compressed debug sections, as produced by GNU gold
1965 with the --compress-debug-sections=zlib flag.
1967 * 64-bit core files are now supported on AIX.
1969 * Thread switching is now supported on Tru64.
1971 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1972 which will be allocated using malloc later in program execution.
1974 * The qXfer:libraries:read remote procotol packet now allows passing a
1975 list of section offsets.
1977 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1978 conditions handling signals delivered during attach or thread creation
1979 have also been fixed.
1981 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1982 From the user's standpoint, all unqualified instances of True and False
1983 are treated as the standard definitions, regardless of context.
1985 * GDB now parses C++ symbol and type names more flexibly. For
1988 template<typename T> class C { };
1991 GDB will now correctly handle all of:
1993 ptype C<char const *>
1994 ptype C<char const*>
1995 ptype C<const char *>
1996 ptype C<const char*>
1998 * New features in the GDB remote stub, gdbserver
2000 - The "--wrapper" command-line argument tells gdbserver to use a
2001 wrapper program to launch programs for debugging.
2003 - On PowerPC and S/390 targets, it is now possible to use a single
2004 gdbserver executable to debug both 32-bit and 64-bit programs.
2005 (This requires gdbserver itself to be built as a 64-bit executable.)
2007 - gdbserver uses the new noack protocol mode for TCP connections to
2008 reduce communications latency, if also supported and enabled in GDB.
2010 - Support for the sparc64-linux-gnu target is now included in
2013 - The amd64-linux build of gdbserver now supports debugging both
2014 32-bit and 64-bit programs.
2016 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2017 now support hardware watchpoints, and will use them automatically
2022 GDB now has support for scripting using Python. Whether this is
2023 available is determined at configure time.
2025 New GDB commands can now be written in Python.
2027 * Ada tasking support
2029 Ada tasks can now be inspected in GDB. The following commands have
2033 Print the list of Ada tasks.
2035 Print detailed information about task number N.
2037 Print the task number of the current task.
2039 Switch the context of debugging to task number N.
2041 * Support for user-defined prefixed commands. The "define" command can
2042 add new commands to existing prefixes, e.g. "target".
2044 * Multi-inferior, multi-process debugging.
2046 GDB now has generalized support for multi-inferior debugging. See
2047 "Debugging Multiple Inferiors" in the manual for more information.
2048 Although availability still depends on target support, the command
2049 set is more uniform now. The GNU/Linux specific multi-forks support
2050 has been migrated to this new framework. This implied some user
2051 visible changes; see "New commands" and also "Removed commands"
2054 * Target descriptions can now describe the target OS ABI. See the
2055 "Target Description Format" section in the user manual for more
2058 * Target descriptions can now describe "compatible" architectures
2059 to indicate that the target can execute applications for a different
2060 architecture in addition to those for the main target architecture.
2061 See the "Target Description Format" section in the user manual for
2064 * Multi-architecture debugging.
2066 GDB now includes general supports for debugging applications on
2067 hybrid systems that use more than one single processor architecture
2068 at the same time. Each such hybrid architecture still requires
2069 specific support to be added. The only hybrid architecture supported
2070 in this version of GDB is the Cell Broadband Engine.
2072 * GDB now supports integrated debugging of Cell/B.E. applications that
2073 use both the PPU and SPU architectures. To enable support for hybrid
2074 Cell/B.E. debugging, you need to configure GDB to support both the
2075 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2076 --enable-targets configure option.
2078 * Non-stop mode debugging.
2080 For some targets, GDB now supports an optional mode of operation in
2081 which you can examine stopped threads while other threads continue
2082 to execute freely. This is referred to as non-stop mode, with the
2083 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2084 section in the user manual for more information.
2086 To be able to support remote non-stop debugging, a remote stub needs
2087 to implement the non-stop mode remote protocol extensions, as
2088 described in the "Remote Non-Stop" section of the user manual. The
2089 GDB remote stub, gdbserver, has been adjusted to support these
2090 extensions on linux targets.
2092 * New commands (for set/show, see "New options" below)
2094 catch syscall [NAME(S) | NUMBER(S)]
2095 Catch system calls. Arguments, which should be names of system
2096 calls or their numbers, mean catch only those syscalls. Without
2097 arguments, every syscall will be caught. When the inferior issues
2098 any of the specified syscalls, GDB will stop and announce the system
2099 call, both when it is called and when its call returns. This
2100 feature is currently available with a native GDB running on the
2101 Linux Kernel, under the following architectures: x86, x86_64,
2102 PowerPC and PowerPC64.
2104 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2106 Search memory for a sequence of bytes.
2108 maint set python print-stack
2109 maint show python print-stack
2110 Show a stack trace when an error is encountered in a Python script.
2113 Invoke CODE by passing it to the Python interpreter.
2118 These allow macros to be defined, undefined, and listed
2122 Show operating system information about processes.
2125 List the inferiors currently under GDB's control.
2128 Switch focus to inferior number NUM.
2131 Detach from inferior number NUM.
2134 Kill inferior number NUM.
2138 set spu stop-on-load
2139 show spu stop-on-load
2140 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2142 set spu auto-flush-cache
2143 show spu auto-flush-cache
2144 Control whether to automatically flush the software-managed cache
2145 during Cell/B.E. debugging.
2147 set sh calling-convention
2148 show sh calling-convention
2149 Control the calling convention used when calling SH target functions.
2152 show debug timestamp
2153 Control display of timestamps with GDB debugging output.
2155 set disassemble-next-line
2156 show disassemble-next-line
2157 Control display of disassembled source lines or instructions when
2160 set remote noack-packet
2161 show remote noack-packet
2162 Set/show the use of remote protocol QStartNoAckMode packet. See above
2163 under "New remote packets."
2165 set remote query-attached-packet
2166 show remote query-attached-packet
2167 Control use of remote protocol `qAttached' (query-attached) packet.
2169 set remote read-siginfo-object
2170 show remote read-siginfo-object
2171 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2174 set remote write-siginfo-object
2175 show remote write-siginfo-object
2176 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2179 set remote reverse-continue
2180 show remote reverse-continue
2181 Control use of remote protocol 'bc' (reverse-continue) packet.
2183 set remote reverse-step
2184 show remote reverse-step
2185 Control use of remote protocol 'bs' (reverse-step) packet.
2187 set displaced-stepping
2188 show displaced-stepping
2189 Control displaced stepping mode. Displaced stepping is a way to
2190 single-step over breakpoints without removing them from the debuggee.
2191 Also known as "out-of-line single-stepping".
2194 show debug displaced
2195 Control display of debugging info for displaced stepping.
2197 maint set internal-error
2198 maint show internal-error
2199 Control what GDB does when an internal error is detected.
2201 maint set internal-warning
2202 maint show internal-warning
2203 Control what GDB does when an internal warning is detected.
2208 Use a wrapper program to launch programs for debugging.
2210 set multiple-symbols (all|ask|cancel)
2211 show multiple-symbols
2212 The value of this variable can be changed to adjust the debugger behavior
2213 when an expression or a breakpoint location contains an ambiguous symbol
2214 name (an overloaded function name, for instance).
2216 set breakpoint always-inserted
2217 show breakpoint always-inserted
2218 Keep breakpoints always inserted in the target, as opposed to inserting
2219 them when resuming the target, and removing them when the target stops.
2220 This option can improve debugger performance on slow remote targets.
2222 set arm fallback-mode (arm|thumb|auto)
2223 show arm fallback-mode
2224 set arm force-mode (arm|thumb|auto)
2226 These commands control how ARM GDB determines whether instructions
2227 are ARM or Thumb. The default for both settings is auto, which uses
2228 the current CPSR value for instructions without symbols; previous
2229 versions of GDB behaved as if "set arm fallback-mode arm".
2231 set disable-randomization
2232 show disable-randomization
2233 Standalone programs run with the virtual address space randomization enabled
2234 by default on some platforms. This option keeps the addresses stable across
2235 multiple debugging sessions.
2239 Control whether other threads are stopped or not when some thread hits
2244 Requests that asynchronous execution is enabled in the target, if available.
2245 In this case, it's possible to resume target in the background, and interact
2246 with GDB while the target is running. "show target-async" displays the
2247 current state of asynchronous execution of the target.
2249 set target-wide-charset
2250 show target-wide-charset
2251 The target-wide-charset is the name of the character set that GDB
2252 uses when printing characters whose type is wchar_t.
2254 set tcp auto-retry (on|off)
2256 set tcp connect-timeout
2257 show tcp connect-timeout
2258 These commands allow GDB to retry failed TCP connections to a remote stub
2259 with a specified timeout period; this is useful if the stub is launched
2260 in parallel with GDB but may not be ready to accept connections immediately.
2262 set libthread-db-search-path
2263 show libthread-db-search-path
2264 Control list of directories which GDB will search for appropriate
2267 set schedule-multiple (on|off)
2268 show schedule-multiple
2269 Allow GDB to resume all threads of all processes or only threads of
2270 the current process.
2274 Use more aggressive caching for accesses to the stack. This improves
2275 performance of remote debugging (particularly backtraces) without
2276 affecting correctness.
2278 set interactive-mode (on|off|auto)
2279 show interactive-mode
2280 Control whether GDB runs in interactive mode (on) or not (off).
2281 When in interactive mode, GDB waits for the user to answer all
2282 queries. Otherwise, GDB does not wait and assumes the default
2283 answer. When set to auto (the default), GDB determines which
2284 mode to use based on the stdin settings.
2289 For program forks, this is replaced by the new more generic `info
2290 inferiors' command. To list checkpoints, you can still use the
2291 `info checkpoints' command, which was an alias for the `info forks'
2295 Replaced by the new `inferior' command. To switch between
2296 checkpoints, you can still use the `restart' command, which was an
2297 alias for the `fork' command.
2300 This is removed, since some targets don't have a notion of
2301 processes. To switch between processes, you can still use the
2302 `inferior' command using GDB's own inferior number.
2305 For program forks, this is replaced by the new more generic `kill
2306 inferior' command. To delete a checkpoint, you can still use the
2307 `delete checkpoint' command, which was an alias for the `delete
2311 For program forks, this is replaced by the new more generic `detach
2312 inferior' command. To detach a checkpoint, you can still use the
2313 `detach checkpoint' command, which was an alias for the `detach
2316 * New native configurations
2318 x86/x86_64 Darwin i[34567]86-*-darwin*
2320 x86_64 MinGW x86_64-*-mingw*
2324 Lattice Mico32 lm32-*
2325 x86 DICOS i[34567]86-*-dicos*
2326 x86_64 DICOS x86_64-*-dicos*
2329 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2330 (mingw32ce) debugging.
2336 These commands were actually not implemented on any target.
2338 *** Changes in GDB 6.8
2340 * New native configurations
2342 NetBSD/hppa hppa*-*netbsd*
2343 Xtensa GNU/Linux xtensa*-*-linux*
2347 NetBSD/hppa hppa*-*-netbsd*
2348 Xtensa GNU/Lunux xtensa*-*-linux*
2350 * Change in command line behavior -- corefiles vs. process ids.
2352 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2353 attaching to process NUMBER fails, GDB no longer attempts to open a
2354 core file named NUMBER. Attaching to a program using the -c option
2355 is no longer supported. Instead, use the '-p' or '--pid' options.
2357 * GDB can now be built as a native debugger for debugging Windows x86
2358 (mingw32) Portable Executable (PE) programs.
2360 * Pending breakpoints no longer change their number when their address
2363 * GDB now supports breakpoints with multiple locations,
2364 including breakpoints on C++ constructors, inside C++ templates,
2365 and in inlined functions.
2367 * GDB's ability to debug optimized code has been improved. GDB more
2368 accurately identifies function bodies and lexical blocks that occupy
2369 more than one contiguous range of addresses.
2371 * Target descriptions can now describe registers for PowerPC.
2373 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2374 registers on PowerPC targets.
2376 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2377 targets even when the libthread_db library is not available.
2379 * The GDB remote stub, gdbserver, now supports the new file transfer
2380 commands (remote put, remote get, and remote delete).
2382 * The GDB remote stub, gdbserver, now supports run and attach in
2383 extended-remote mode.
2385 * hppa*64*-*-hpux11* target broken
2386 The debugger is unable to start a program and fails with the following
2387 error: "Error trying to get information about dynamic linker".
2388 The gdb-6.7 release is also affected.
2390 * GDB now supports the --enable-targets= configure option to allow
2391 building a single GDB executable that supports multiple remote
2392 target architectures.
2394 * GDB now supports debugging C and C++ programs which use the
2395 Decimal Floating Point extension. In addition, the PowerPC target
2396 now has a set of pseudo-registers to inspect decimal float values
2397 stored in two consecutive float registers.
2399 * The -break-insert MI command can optionally create pending
2402 * Improved support for debugging Ada
2403 Many improvements to the Ada language support have been made. These
2405 - Better support for Ada2005 interface types
2406 - Improved handling of arrays and slices in general
2407 - Better support for Taft-amendment types
2408 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2410 - Improved command completion in Ada
2413 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2418 set print frame-arguments (all|scalars|none)
2419 show print frame-arguments
2420 The value of this variable can be changed to control which argument
2421 values should be printed by the debugger when displaying a frame.
2426 Transfer files to and from a remote target, and delete remote files.
2433 Transfer files to and from a remote target, and delete remote files.
2435 * New remote packets
2442 Open, close, read, write, and delete files on the remote system.
2445 Attach to an existing process on the remote system, in extended-remote
2449 Run a new process on the remote system, in extended-remote mode.
2451 *** Changes in GDB 6.7
2453 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2454 bfd, libiberty and opcodes, as revealed by static analysis donated by
2455 Coverity, Inc. (http://scan.coverity.com).
2457 * When looking up multiply-defined global symbols, GDB will now prefer the
2458 symbol definition in the current shared library if it was built using the
2459 -Bsymbolic linker option.
2461 * When the Text User Interface (TUI) is not configured, GDB will now
2462 recognize the -tui command-line option and print a message that the TUI
2465 * The GDB remote stub, gdbserver, now has lower overhead for high
2466 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2468 * GDB for MIPS targets now autodetects whether a remote target provides
2469 32-bit or 64-bit register values.
2471 * Support for C++ member pointers has been improved.
2473 * GDB now understands XML target descriptions, which specify the
2474 target's overall architecture. GDB can read a description from
2475 a local file or over the remote serial protocol.
2477 * Vectors of single-byte data use a new integer type which is not
2478 automatically displayed as character or string data.
2480 * The /s format now works with the print command. It displays
2481 arrays of single-byte integers and pointers to single-byte integers
2484 * Target descriptions can now describe target-specific registers,
2485 for architectures which have implemented the support (currently
2486 only ARM, M68K, and MIPS).
2488 * GDB and the GDB remote stub, gdbserver, now support the XScale
2491 * The GDB remote stub, gdbserver, has been updated to support
2492 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2493 has been rewritten to use the standard GDB remote protocol.
2495 * GDB can now step into C++ functions which are called through thunks.
2497 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2499 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2500 layout. It also supports a TextSeg= and DataSeg= response when only
2501 segment base addresses (rather than offsets) are available.
2503 * The /i format now outputs any trailing branch delay slot instructions
2504 immediately following the last instruction within the count specified.
2506 * The GDB remote protocol "T" stop reply packet now supports a
2507 "library" response. Combined with the new "qXfer:libraries:read"
2508 packet, this response allows GDB to debug shared libraries on targets
2509 where the operating system manages the list of loaded libraries (e.g.
2510 Windows and SymbianOS).
2512 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2513 (DLLs) on Windows and Windows CE targets.
2515 * GDB now supports a faster verification that a .debug file matches its binary
2516 according to its build-id signature, if the signature is present.
2522 Enable or disable hardware flow control (RTS/CTS) on the serial port
2523 when debugging using remote targets.
2525 set mem inaccessible-by-default
2526 show mem inaccessible-by-default
2527 If the target supplies a memory map, for instance via the remote
2528 protocol's "qXfer:memory-map:read" packet, setting this variable
2529 prevents GDB from accessing memory outside the memory map. This
2530 is useful for targets with memory mapped registers or which react
2531 badly to accesses of unmapped address space.
2533 set breakpoint auto-hw
2534 show breakpoint auto-hw
2535 If the target supplies a memory map, for instance via the remote
2536 protocol's "qXfer:memory-map:read" packet, setting this variable
2537 lets GDB use hardware breakpoints automatically for memory regions
2538 where it can not use software breakpoints. This covers both the
2539 "break" command and internal breakpoints used for other commands
2540 including "next" and "finish".
2543 catch exception unhandled
2544 Stop the program execution when Ada exceptions are raised.
2547 Stop the program execution when an Ada assertion failed.
2551 Set an alternate system root for target files. This is a more
2552 general version of "set solib-absolute-prefix", which is now
2553 an alias to "set sysroot".
2556 Provide extended SPU facility status information. This set of
2557 commands is available only when debugging the Cell/B.E. SPU
2560 * New native configurations
2562 OpenBSD/sh sh*-*openbsd*
2565 unset tdesc filename
2567 Use the specified local file as an XML target description, and do
2568 not query the target for its built-in description.
2572 OpenBSD/sh sh*-*-openbsd*
2573 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2574 Toshiba Media Processor mep-elf
2576 * New remote packets
2579 Ignore the specified signals; pass them directly to the debugged program
2580 without stopping other threads or reporting them to GDB.
2582 qXfer:features:read:
2583 Read an XML target description from the target, which describes its
2588 Read or write contents of an spufs file on the target system. These
2589 packets are available only on the Cell/B.E. SPU architecture.
2591 qXfer:libraries:read:
2592 Report the loaded shared libraries. Combined with new "T" packet
2593 response, this packet allows GDB to debug shared libraries on
2594 targets where the operating system manages the list of loaded
2595 libraries (e.g. Windows and SymbianOS).
2599 Support for these obsolete configurations has been removed.
2607 i[34567]86-*-lynxos*
2608 i[34567]86-*-netware*
2609 i[34567]86-*-sco3.2v5*
2610 i[34567]86-*-sco3.2v4*
2612 i[34567]86-*-sysv4.2*
2615 i[34567]86-*-unixware2*
2616 i[34567]86-*-unixware*
2625 * Other removed features
2632 Various m68k-only ROM monitors.
2639 Various Renesas ROM monitors and debugging interfaces for SH and
2644 Support for a Macraigor serial interface to on-chip debugging.
2645 GDB does not directly support the newer parallel or USB
2650 A debug information format. The predecessor to DWARF 2 and
2651 DWARF 3, which are still supported.
2653 Support for the HP aCC compiler on HP-UX/PA-RISC
2655 SOM-encapsulated symbolic debugging information, automatic
2656 invocation of pxdb, and the aCC custom C++ ABI. This does not
2657 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2658 with aCC can still be debugged on an assembly level.
2660 MIPS ".pdr" sections
2662 A MIPS-specific format used to describe stack frame layout
2663 in debugging information.
2667 GDB could work with an older version of Guile to debug
2668 the interpreter and Scheme programs running in it.
2670 set mips stack-arg-size
2671 set mips saved-gpreg-size
2673 Use "set mips abi" to control parameter passing for MIPS.
2675 *** Changes in GDB 6.6
2680 Cell Broadband Engine SPU spu-elf
2682 * GDB can now be configured as a cross-debugger targeting native Windows
2683 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2684 running on a Windows system over TCP/IP to debug Windows programs.
2686 * The GDB remote stub, gdbserver, has been updated to support Windows and
2687 Cygwin debugging. Both single-threaded and multi-threaded programs are
2690 * The "set trust-readonly-sections" command works again. This command was
2691 broken in GDB 6.3, 6.4, and 6.5.
2693 * The "load" command now supports writing to flash memory, if the remote
2694 stub provides the required support.
2696 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2697 longer requires symbolic debug information (e.g. DWARF-2).
2702 unset substitute-path
2703 show substitute-path
2704 Manage a list of substitution rules that GDB uses to rewrite the name
2705 of the directories where the sources are located. This can be useful
2706 for instance when the sources were moved to a different location
2707 between compilation and debugging.
2711 Print each CLI command as it is executed. Each command is prefixed with
2712 a number of `+' symbols representing the nesting depth.
2713 The source command now has a `-v' option to enable the same feature.
2717 The ARM Demon monitor support (RDP protocol, "target rdp").
2719 Kernel Object Display, an embedded debugging feature which only worked with
2720 an obsolete version of Cisco IOS.
2722 The 'set download-write-size' and 'show download-write-size' commands.
2724 * New remote packets
2727 Tell a stub about GDB client features, and request remote target features.
2728 The first feature implemented is PacketSize, which allows the target to
2729 specify the size of packets it can handle - to minimize the number of
2730 packets required and improve performance when connected to a remote
2734 Fetch an OS auxilliary vector from the remote stub. This packet is a
2735 more efficient replacement for qPart:auxv:read.
2737 qXfer:memory-map:read:
2738 Fetch a memory map from the remote stub, including information about
2739 RAM, ROM, and flash memory devices.
2744 Erase and program a flash memory device.
2746 * Removed remote packets
2749 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2750 used it, and only gdbserver implemented it.
2752 *** Changes in GDB 6.5
2756 Renesas M32C/M16C m32c-elf
2758 Morpho Technologies ms1 ms1-elf
2762 init-if-undefined Initialize a convenience variable, but
2763 only if it doesn't already have a value.
2765 The following commands are presently only implemented for native GNU/Linux:
2767 checkpoint Save a snapshot of the program state.
2769 restart <n> Return the program state to a
2770 previously saved state.
2772 info checkpoints List currently saved checkpoints.
2774 delete-checkpoint <n> Delete a previously saved checkpoint.
2776 set|show detach-on-fork Tell gdb whether to detach from a newly
2777 forked process, or to keep debugging it.
2779 info forks List forks of the user program that
2780 are available to be debugged.
2782 fork <n> Switch to debugging one of several
2783 forks of the user program that are
2784 available to be debugged.
2786 delete-fork <n> Delete a fork from the list of forks
2787 that are available to be debugged (and
2788 kill the forked process).
2790 detach-fork <n> Delete a fork from the list of forks
2791 that are available to be debugged (and
2792 allow the process to continue).
2796 Morpho Technologies ms2 ms1-elf
2798 * Improved Windows host support
2800 GDB now builds as a cross debugger hosted on i686-mingw32, including
2801 native console support, and remote communications using either
2802 network sockets or serial ports.
2804 * Improved Modula-2 language support
2806 GDB can now print most types in the Modula-2 syntax. This includes:
2807 basic types, set types, record types, enumerated types, range types,
2808 pointer types and ARRAY types. Procedure var parameters are correctly
2809 printed and hexadecimal addresses and character constants are also
2810 written in the Modula-2 syntax. Best results can be obtained by using
2811 GNU Modula-2 together with the -gdwarf-2 command line option.
2815 The ARM rdi-share module.
2817 The Netware NLM debug server.
2819 *** Changes in GDB 6.4
2821 * New native configurations
2823 OpenBSD/arm arm*-*-openbsd*
2824 OpenBSD/mips64 mips64-*-openbsd*
2828 Morpho Technologies ms1 ms1-elf
2830 * New command line options
2832 --batch-silent As for --batch, but totally silent.
2833 --return-child-result The debugger will exist with the same value
2834 the child (debugged) program exited with.
2835 --eval-command COMMAND, -ex COMMAND
2836 Execute a single GDB CLI command. This may be
2837 specified multiple times and in conjunction
2838 with the --command (-x) option.
2840 * Deprecated commands removed
2842 The following commands, that were deprecated in 2000, have been
2846 set|show arm disassembly-flavor set|show arm disassembler
2847 othernames set arm disassembler
2848 set|show remotedebug set|show debug remote
2849 set|show archdebug set|show debug arch
2850 set|show eventdebug set|show debug event
2853 * New BSD user-level threads support
2855 It is now possible to debug programs using the user-level threads
2856 library on OpenBSD and FreeBSD. Currently supported (target)
2859 FreeBSD/amd64 x86_64-*-freebsd*
2860 FreeBSD/i386 i386-*-freebsd*
2861 OpenBSD/i386 i386-*-openbsd*
2863 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2864 are not yet supported.
2866 * New support for Matsushita MN10300 w/sim added
2867 (Work in progress). mn10300-elf.
2869 * REMOVED configurations and files
2871 VxWorks and the XDR protocol *-*-vxworks
2872 Motorola MCORE mcore-*-*
2873 National Semiconductor NS32000 ns32k-*-*
2875 * New "set print array-indexes" command
2877 After turning this setting "on", GDB prints the index of each element
2878 when displaying arrays. The default is "off" to preserve the previous
2881 * VAX floating point support
2883 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2885 * User-defined command support
2887 In addition to using $arg0..$arg9 for argument passing, it is now possible
2888 to use $argc to determine now many arguments have been passed. See the
2889 section on user-defined commands in the user manual for more information.
2891 *** Changes in GDB 6.3:
2893 * New command line option
2895 GDB now accepts -l followed by a number to set the timeout for remote
2898 * GDB works with GCC -feliminate-dwarf2-dups
2900 GDB now supports a more compact representation of DWARF-2 debug
2901 information using DW_FORM_ref_addr references. These are produced
2902 by GCC with the option -feliminate-dwarf2-dups and also by some
2903 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2904 to use -feliminate-dwarf2-dups.
2906 * Internationalization
2908 When supported by the host system, GDB will be built with
2909 internationalization (libintl). The task of marking up the sources is
2910 continued, we're looking forward to our first translation.
2914 Initial support for debugging programs compiled with the GNAT
2915 implementation of the Ada programming language has been integrated
2916 into GDB. In this release, support is limited to expression evaluation.
2918 * New native configurations
2920 GNU/Linux/m32r m32r-*-linux-gnu
2924 GDB's remote protocol now includes support for the 'p' packet. This
2925 packet is used to fetch individual registers from a remote inferior.
2927 * END-OF-LIFE registers[] compatibility module
2929 GDB's internal register infrastructure has been completely rewritten.
2930 The new infrastructure making possible the implementation of key new
2931 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2934 GDB 6.3 will be the last release to include the the registers[]
2935 compatibility module that allowed out-of-date configurations to
2936 continue to work. This change directly impacts the following
2946 powerpc bdm protocol
2948 Unless there is activity to revive these configurations, they will be
2949 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2951 * OBSOLETE configurations and files
2953 Configurations that have been declared obsolete in this release have
2954 been commented out. Unless there is activity to revive these
2955 configurations, the next release of GDB will have their sources
2956 permanently REMOVED.
2965 *** Changes in GDB 6.2.1:
2967 * MIPS `break main; run' gave an heuristic-fence-post warning
2969 When attempting to run even a simple program, a warning about
2970 heuristic-fence-post being hit would be reported. This problem has
2973 * MIPS IRIX 'long double' crashed GDB
2975 When examining a long double variable, GDB would get a segmentation
2976 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2977 IRIX long double values).
2981 A bug in the VAX stack code was causing problems with the "next"
2982 command. This problem has been fixed.
2984 *** Changes in GDB 6.2:
2986 * Fix for ``many threads''
2988 On GNU/Linux systems that use the NPTL threads library, a program
2989 rapidly creating and deleting threads would confuse GDB leading to the
2992 ptrace: No such process.
2993 thread_db_get_info: cannot get thread info: generic error
2995 This problem has been fixed.
2997 * "-async" and "-noasync" options removed.
2999 Support for the broken "-noasync" option has been removed (it caused
3002 * New ``start'' command.
3004 This command runs the program until the begining of the main procedure.
3006 * New BSD Kernel Data Access Library (libkvm) interface
3008 Using ``target kvm'' it is now possible to debug kernel core dumps and
3009 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3010 platforms. Currently supported (native-only) configurations are:
3012 FreeBSD/amd64 x86_64-*-freebsd*
3013 FreeBSD/i386 i?86-*-freebsd*
3014 NetBSD/i386 i?86-*-netbsd*
3015 NetBSD/m68k m68*-*-netbsd*
3016 NetBSD/sparc sparc-*-netbsd*
3017 OpenBSD/amd64 x86_64-*-openbsd*
3018 OpenBSD/i386 i?86-*-openbsd*
3019 OpenBSD/m68k m68*-openbsd*
3020 OpenBSD/sparc sparc-*-openbsd*
3022 * Signal trampoline code overhauled
3024 Many generic problems with GDB's signal handling code have been fixed.
3025 These include: backtraces through non-contiguous stacks; recognition
3026 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3027 call; backtrace through a signal trampoline; step into and out of
3028 signal handlers; and single-stepping in the signal trampoline.
3030 Please note that kernel bugs are a limiting factor here. These
3031 features have been shown to work on an s390 GNU/Linux system that
3032 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3034 * Cygwin support for DWARF 2 added.
3036 * New native configurations
3038 GNU/Linux/hppa hppa*-*-linux*
3039 OpenBSD/hppa hppa*-*-openbsd*
3040 OpenBSD/m68k m68*-*-openbsd*
3041 OpenBSD/m88k m88*-*-openbsd*
3042 OpenBSD/powerpc powerpc-*-openbsd*
3043 NetBSD/vax vax-*-netbsd*
3044 OpenBSD/vax vax-*-openbsd*
3046 * END-OF-LIFE frame compatibility module
3048 GDB's internal frame infrastructure has been completely rewritten.
3049 The new infrastructure making it possible to support key new features
3050 including DWARF 2 Call Frame Information. To aid in the task of
3051 migrating old configurations to this new infrastructure, a
3052 compatibility module, that allowed old configurations to continue to
3053 work, was also included.
3055 GDB 6.2 will be the last release to include this frame compatibility
3056 module. This change directly impacts the following configurations:
3066 Unless there is activity to revive these configurations, they will be
3067 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3069 * REMOVED configurations and files
3071 Sun 3, running SunOS 3 m68*-*-sunos3*
3072 Sun 3, running SunOS 4 m68*-*-sunos4*
3073 Sun 2, running SunOS 3 m68000-*-sunos3*
3074 Sun 2, running SunOS 4 m68000-*-sunos4*
3075 Motorola 680x0 running LynxOS m68*-*-lynxos*
3076 AT&T 3b1/Unix pc m68*-att-*
3077 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3078 decstation mips-dec-* mips-little-*
3079 riscos mips-*-riscos* mips-*-sysv*
3080 sonymips mips-sony-*
3081 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3083 *** Changes in GDB 6.1.1:
3085 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3087 The TUI (Text-mode User Interface) is now built as part of a default
3088 GDB configuration. It is enabled by either selecting the TUI with the
3089 command line option "-i=tui" or by running the separate "gdbtui"
3090 program. For more information on the TUI, see the manual "Debugging
3093 * Pending breakpoint support (also included in GDB 6.1)
3095 Support has been added to allow you to specify breakpoints in shared
3096 libraries that have not yet been loaded. If a breakpoint location
3097 cannot be found, and the "breakpoint pending" option is set to auto,
3098 GDB queries you if you wish to make the breakpoint pending on a future
3099 shared-library load. If and when GDB resolves the breakpoint symbol,
3100 the pending breakpoint is removed as one or more regular breakpoints
3103 Pending breakpoints are very useful for GCJ Java debugging.
3105 * Fixed ISO-C build problems
3107 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3108 non ISO-C code that stopped them being built using a more strict ISO-C
3109 compiler (e.g., IBM's C compiler).
3111 * Fixed build problem on IRIX 5
3113 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3114 wasn't able to compile compile on an IRIX 5 system.
3116 * Added execute permission to gdb/gdbserver/configure
3118 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3119 permission. This bug would cause configure to fail on a number of
3120 systems (Solaris, IRIX). Ref: server/519.
3122 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3124 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3125 has been updated to use constant array sizes.
3127 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3129 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3130 its generated DWARF Call Frame Info. This encoding was causing GDB to
3131 panic, that panic has been fixed. Ref: gdb/1628.
3133 * Fixed a problem when examining parameters in shared library code.
3135 When examining parameters in optimized shared library code generated
3136 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3137 not available''. GDB now correctly displays the variable's value.
3139 *** Changes in GDB 6.1:
3141 * Removed --with-mmalloc
3143 Support for the mmalloc memory manager has been removed, as it
3144 conflicted with the internal gdb byte cache.
3146 * Changes in AMD64 configurations
3148 The AMD64 target now includes the %cs and %ss registers. As a result
3149 the AMD64 remote protocol has changed; this affects the floating-point
3150 and SSE registers. If you rely on those registers for your debugging,
3151 you should upgrade gdbserver on the remote side.
3153 * Revised SPARC target
3155 The SPARC target has been completely revised, incorporating the
3156 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3157 support for LynxOS and SunOS 4 has been dropped. Calling functions
3158 from within GDB on operating systems with a non-executable stack
3159 (Solaris, OpenBSD) now works.
3163 GDB has a new C++ demangler which does a better job on the mangled
3164 names generated by current versions of g++. It also runs faster, so
3165 with this and other changes gdb should now start faster on large C++
3168 * DWARF 2 Location Expressions
3170 GDB support for location expressions has been extended to support function
3171 arguments and frame bases. Older versions of GDB could crash when they
3174 * C++ nested types and namespaces
3176 GDB's support for nested types and namespaces in C++ has been
3177 improved, especially if you use the DWARF 2 debugging format. (This
3178 is the default for recent versions of GCC on most platforms.)
3179 Specifically, if you have a class "Inner" defined within a class or
3180 namespace "Outer", then GDB realizes that the class's name is
3181 "Outer::Inner", not simply "Inner". This should greatly reduce the
3182 frequency of complaints about not finding RTTI symbols. In addition,
3183 if you are stopped at inside of a function defined within a namespace,
3184 GDB modifies its name lookup accordingly.
3186 * New native configurations
3188 NetBSD/amd64 x86_64-*-netbsd*
3189 OpenBSD/amd64 x86_64-*-openbsd*
3190 OpenBSD/alpha alpha*-*-openbsd*
3191 OpenBSD/sparc sparc-*-openbsd*
3192 OpenBSD/sparc64 sparc64-*-openbsd*
3194 * New debugging protocols
3196 M32R with SDI protocol m32r-*-elf*
3198 * "set prompt-escape-char" command deleted.
3200 The command "set prompt-escape-char" has been deleted. This command,
3201 and its very obscure effet on GDB's prompt, was never documented,
3202 tested, nor mentioned in the NEWS file.
3204 * OBSOLETE configurations and files
3206 Configurations that have been declared obsolete in this release have
3207 been commented out. Unless there is activity to revive these
3208 configurations, the next release of GDB will have their sources
3209 permanently REMOVED.
3211 Sun 3, running SunOS 3 m68*-*-sunos3*
3212 Sun 3, running SunOS 4 m68*-*-sunos4*
3213 Sun 2, running SunOS 3 m68000-*-sunos3*
3214 Sun 2, running SunOS 4 m68000-*-sunos4*
3215 Motorola 680x0 running LynxOS m68*-*-lynxos*
3216 AT&T 3b1/Unix pc m68*-att-*
3217 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3218 decstation mips-dec-* mips-little-*
3219 riscos mips-*-riscos* mips-*-sysv*
3220 sonymips mips-sony-*
3221 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3223 * REMOVED configurations and files
3225 SGI Irix-4.x mips-sgi-irix4 or iris4
3226 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3227 Z8000 simulator z8k-zilog-none or z8ksim
3228 Matsushita MN10200 w/simulator mn10200-*-*
3229 H8/500 simulator h8500-hitachi-hms or h8500hms
3230 HP/PA running BSD hppa*-*-bsd*
3231 HP/PA running OSF/1 hppa*-*-osf*
3232 HP/PA Pro target hppa*-*-pro*
3233 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3234 386BSD i[3456]86-*-bsd*
3235 Sequent family i[3456]86-sequent-sysv4*
3236 i[3456]86-sequent-sysv*
3237 i[3456]86-sequent-bsd*
3238 SPARC running LynxOS sparc-*-lynxos*
3239 SPARC running SunOS 4 sparc-*-sunos4*
3240 Tsqware Sparclet sparclet-*-*
3241 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3243 *** Changes in GDB 6.0:
3247 Support for debugging the Objective-C programming language has been
3248 integrated into GDB.
3250 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3252 DWARF 2's Call Frame Information makes available compiler generated
3253 information that more exactly describes the program's run-time stack.
3254 By using this information, GDB is able to provide more robust stack
3257 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3258 have been updated to use a new backtrace mechanism which includes
3259 DWARF 2 CFI support.
3263 GDB's remote protocol has been extended to include support for hosted
3264 file I/O (where the remote target uses GDB's file system). See GDB's
3265 remote protocol documentation for details.
3267 * All targets using the new architecture framework.
3269 All of GDB's targets have been updated to use the new internal
3270 architecture framework. The way is now open for future GDB releases
3271 to include cross-architecture native debugging support (i386 on amd64,
3274 * GNU/Linux's Thread Local Storage (TLS)
3276 GDB now includes support for for the GNU/Linux implementation of
3277 per-thread variables.
3279 * GNU/Linux's Native POSIX Thread Library (NPTL)
3281 GDB's thread code has been updated to work with either the new
3282 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3284 * Separate debug info.
3286 GDB, in conjunction with BINUTILS, now supports a mechanism for
3287 automatically loading debug information from a separate file. Instead
3288 of shipping full debug and non-debug versions of system libraries,
3289 system integrators can now instead ship just the stripped libraries
3290 and optional debug files.
3292 * DWARF 2 Location Expressions
3294 DWARF 2 Location Expressions allow the compiler to more completely
3295 describe the location of variables (even in optimized code) to the
3298 GDB now includes preliminary support for location expressions (support
3299 for DW_OP_piece is still missing).
3303 A number of long standing bugs that caused GDB to die while starting a
3304 Java application have been fixed. GDB's Java support is now
3305 considered "useable".
3307 * GNU/Linux support for fork, vfork, and exec.
3309 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3310 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3313 * GDB supports logging output to a file
3315 There are two new commands, "set logging" and "show logging", which can be
3316 used to capture GDB's output to a file.
3318 * The meaning of "detach" has changed for gdbserver
3320 The "detach" command will now resume the application, as documented. To
3321 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3324 * d10v, m68hc11 `regs' command deprecated
3326 The `info registers' command has been updated so that it displays the
3327 registers using a format identical to the old `regs' command.
3331 A new command, "maint set profile on/off", has been added. This command can
3332 be used to enable or disable profiling while running GDB, to profile a
3333 session or a set of commands. In addition there is a new configure switch,
3334 "--enable-profiling", which will cause GDB to be compiled with profiling
3335 data, for more informative profiling results.
3337 * Default MI syntax changed to "mi2".
3339 The default MI (machine interface) syntax, enabled by the command line
3340 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3341 "mi1", can be enabled by specifying the option "-i=mi1".
3343 Support for the original "mi0" syntax (included in GDB 5.0) has been
3346 Fix for gdb/192: removed extraneous space when displaying frame level.
3347 Fix for gdb/672: update changelist is now output in mi list format.
3348 Fix for gdb/702: a -var-assign that updates the value now shows up
3349 in a subsequent -var-update.
3351 * New native configurations.
3353 FreeBSD/amd64 x86_64-*-freebsd*
3355 * Multi-arched targets.
3357 HP/PA HPUX11 hppa*-*-hpux*
3358 Renesas M32R/D w/simulator m32r-*-elf*
3360 * OBSOLETE configurations and files
3362 Configurations that have been declared obsolete in this release have
3363 been commented out. Unless there is activity to revive these
3364 configurations, the next release of GDB will have their sources
3365 permanently REMOVED.
3367 Z8000 simulator z8k-zilog-none or z8ksim
3368 Matsushita MN10200 w/simulator mn10200-*-*
3369 H8/500 simulator h8500-hitachi-hms or h8500hms
3370 HP/PA running BSD hppa*-*-bsd*
3371 HP/PA running OSF/1 hppa*-*-osf*
3372 HP/PA Pro target hppa*-*-pro*
3373 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3374 Sequent family i[3456]86-sequent-sysv4*
3375 i[3456]86-sequent-sysv*
3376 i[3456]86-sequent-bsd*
3377 Tsqware Sparclet sparclet-*-*
3378 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3380 * REMOVED configurations and files
3383 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3384 IBM AIX PS/2 i[3456]86-*-aix
3385 i386 running Mach 3.0 i[3456]86-*-mach3*
3386 i386 running Mach i[3456]86-*-mach*
3387 i386 running OSF/1 i[3456]86-*osf1mk*
3388 HP/Apollo 68k Family m68*-apollo*-sysv*,
3390 m68*-hp-bsd*, m68*-hp-hpux*
3391 Argonaut Risc Chip (ARC) arc-*-*
3392 Mitsubishi D30V d30v-*-*
3393 Fujitsu FR30 fr30-*-elf*
3394 OS/9000 i[34]86-*-os9k
3395 I960 with MON960 i960-*-coff
3397 * MIPS $fp behavior changed
3399 The convenience variable $fp, for the MIPS, now consistently returns
3400 the address of the current frame's base. Previously, depending on the
3401 context, $fp could refer to either $sp or the current frame's base
3402 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3403 The GNU Source-Level Debugger''.
3405 *** Changes in GDB 5.3:
3407 * GNU/Linux shared library multi-threaded performance improved.
3409 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3410 `/proc', in preference to `ptrace' for memory reads. This may result
3411 in an improvement in the start-up time of multi-threaded, shared
3412 library applications when run under GDB. One GDB user writes: ``loads
3413 shared libs like mad''.
3415 * ``gdbserver'' now supports multi-threaded applications on some targets
3417 Support for debugging multi-threaded applications which use
3418 the GNU/Linux LinuxThreads package has been added for
3419 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3420 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3422 * GDB now supports C/C++ preprocessor macros.
3424 GDB now expands preprocessor macro invocations in C/C++ expressions,
3425 and provides various commands for showing macro definitions and how
3428 The new command `macro expand EXPRESSION' expands any macro
3429 invocations in expression, and shows the result.
3431 The new command `show macro MACRO-NAME' shows the definition of the
3432 macro named MACRO-NAME, and where it was defined.
3434 Most compilers don't include information about macros in the debugging
3435 information by default. In GCC 3.1, for example, you need to compile
3436 your program with the options `-gdwarf-2 -g3'. If the macro
3437 information is present in the executable, GDB will read it.
3439 * Multi-arched targets.
3441 DEC Alpha (partial) alpha*-*-*
3442 DEC VAX (partial) vax-*-*
3444 National Semiconductor NS32000 (partial) ns32k-*-*
3445 Motorola 68000 (partial) m68k-*-*
3446 Motorola MCORE mcore-*-*
3450 Fujitsu FRV architecture added by Red Hat frv*-*-*
3453 * New native configurations
3455 Alpha NetBSD alpha*-*-netbsd*
3456 SH NetBSD sh*-*-netbsdelf*
3457 MIPS NetBSD mips*-*-netbsd*
3458 UltraSPARC NetBSD sparc64-*-netbsd*
3460 * OBSOLETE configurations and files
3462 Configurations that have been declared obsolete in this release have
3463 been commented out. Unless there is activity to revive these
3464 configurations, the next release of GDB will have their sources
3465 permanently REMOVED.
3467 Mitsubishi D30V d30v-*-*
3468 OS/9000 i[34]86-*-os9k
3469 IBM AIX PS/2 i[3456]86-*-aix
3470 Fujitsu FR30 fr30-*-elf*
3471 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3472 Argonaut Risc Chip (ARC) arc-*-*
3473 i386 running Mach 3.0 i[3456]86-*-mach3*
3474 i386 running Mach i[3456]86-*-mach*
3475 i386 running OSF/1 i[3456]86-*osf1mk*
3476 HP/Apollo 68k Family m68*-apollo*-sysv*,
3478 m68*-hp-bsd*, m68*-hp-hpux*
3479 I960 with MON960 i960-*-coff
3481 * OBSOLETE languages
3483 CHILL, a Pascal like language used by telecommunications companies.
3485 * REMOVED configurations and files
3487 AMD 29k family via UDI a29k-amd-udi, udi29k
3488 A29K VxWorks a29k-*-vxworks
3489 AMD 29000 embedded, using EBMON a29k-none-none
3490 AMD 29000 embedded with COFF a29k-none-coff
3491 AMD 29000 embedded with a.out a29k-none-aout
3493 testsuite/gdb.hp/gdb.threads-hp/ directory
3495 * New command "set max-user-call-depth <nnn>"
3497 This command allows the user to limit the call depth of user-defined
3498 commands. The default is 1024.
3500 * Changes in FreeBSD/i386 native debugging.
3502 Support for the "generate-core-file" has been added.
3504 * New commands "dump", "append", and "restore".
3506 These commands allow data to be copied from target memory
3507 to a bfd-format or binary file (dump and append), and back
3508 from a file into memory (restore).
3510 * Improved "next/step" support on multi-processor Alpha Tru64.
3512 The previous single-step mechanism could cause unpredictable problems,
3513 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3514 of a software single-step mechanism prevents this.
3516 *** Changes in GDB 5.2.1:
3524 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3525 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3526 Fix, by Joel Brobecker imported from mainline.
3528 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3529 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3530 Fix, by Fred Fish, imported from mainline.
3532 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3533 Surprisingly enough, it works now.
3534 By Michal Ludvig, imported from mainline.
3536 i386 hardware watchpoint support:
3537 avoid misses on second run for some targets.
3538 By Pierre Muller, imported from mainline.
3540 *** Changes in GDB 5.2:
3542 * New command "set trust-readonly-sections on[off]".
3544 This command is a hint that tells gdb that read-only sections
3545 really are read-only (ie. that their contents will not change).
3546 In this mode, gdb will go to the object file rather than the
3547 target to read memory from read-only sections (such as ".text").
3548 This can be a significant performance improvement on some
3549 (notably embedded) targets.
3551 * New command "generate-core-file" (or "gcore").
3553 This new gdb command allows the user to drop a core file of the child
3554 process state at any time. So far it's been implemented only for
3555 GNU/Linux and Solaris, but should be relatively easily ported to other
3556 hosts. Argument is core file name (defaults to core.<pid>).
3558 * New command line option
3560 GDB now accepts --pid or -p followed by a process id.
3562 * Change in command line behavior -- corefiles vs. process ids.
3564 There is a subtle behavior in the way in which GDB handles
3565 command line arguments. The first non-flag argument is always
3566 a program to debug, but the second non-flag argument may either
3567 be a corefile or a process id. Previously, GDB would attempt to
3568 open the second argument as a corefile, and if that failed, would
3569 issue a superfluous error message and then attempt to attach it as
3570 a process. Now, if the second argument begins with a non-digit,
3571 it will be treated as a corefile. If it begins with a digit,
3572 GDB will attempt to attach it as a process, and if no such process
3573 is found, will then attempt to open it as a corefile.
3575 * Changes in ARM configurations.
3577 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3578 configuration is fully multi-arch.
3580 * New native configurations
3582 ARM NetBSD arm*-*-netbsd*
3583 x86 OpenBSD i[3456]86-*-openbsd*
3584 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3585 Sparc64 running FreeBSD sparc64-*-freebsd*
3589 Sanyo XStormy16 xstormy16-elf
3591 * OBSOLETE configurations and files
3593 Configurations that have been declared obsolete in this release have
3594 been commented out. Unless there is activity to revive these
3595 configurations, the next release of GDB will have their sources
3596 permanently REMOVED.
3598 AMD 29k family via UDI a29k-amd-udi, udi29k
3599 A29K VxWorks a29k-*-vxworks
3600 AMD 29000 embedded, using EBMON a29k-none-none
3601 AMD 29000 embedded with COFF a29k-none-coff
3602 AMD 29000 embedded with a.out a29k-none-aout
3604 testsuite/gdb.hp/gdb.threads-hp/ directory
3606 * REMOVED configurations and files
3608 TI TMS320C80 tic80-*-*
3610 PowerPC Solaris powerpcle-*-solaris*
3611 PowerPC Windows NT powerpcle-*-cygwin32
3612 PowerPC Netware powerpc-*-netware*
3613 Harris/CXUX m88k m88*-harris-cxux*
3614 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3615 ns32k-utek-sysv* ns32k-utek-*
3616 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3617 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3618 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3619 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3620 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3622 * Changes to command line processing
3624 The new `--args' feature can be used to specify command-line arguments
3625 for the inferior from gdb's command line.
3627 * Changes to key bindings
3629 There is a new `operate-and-get-next' function bound to `C-o'.
3631 *** Changes in GDB 5.1.1
3633 Fix compile problem on DJGPP.
3635 Fix a problem with floating-point registers on the i386 being
3638 Fix to stop GDB crashing on .debug_str debug info.
3640 Numerous documentation fixes.
3642 Numerous testsuite fixes.
3644 *** Changes in GDB 5.1:
3646 * New native configurations
3648 Alpha FreeBSD alpha*-*-freebsd*
3649 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3650 MIPS GNU/Linux mips*-*-linux*
3651 MIPS SGI Irix 6.x mips*-sgi-irix6*
3652 ia64 AIX ia64-*-aix*
3653 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3657 Motorola 68HC11 and 68HC12 m68hc11-elf
3659 UltraSparc running GNU/Linux sparc64-*-linux*
3661 * OBSOLETE configurations and files
3663 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3664 Harris/CXUX m88k m88*-harris-cxux*
3665 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3666 ns32k-utek-sysv* ns32k-utek-*
3667 TI TMS320C80 tic80-*-*
3669 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3670 PowerPC Solaris powerpcle-*-solaris*
3671 PowerPC Windows NT powerpcle-*-cygwin32
3672 PowerPC Netware powerpc-*-netware*
3673 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3674 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3675 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3676 Apple Macintosh (MPW) host N/A
3678 stuff.c (Program to stuff files into a specially prepared space in kdb)
3679 kdb-start.c (Main loop for the standalone kernel debugger)
3681 Configurations that have been declared obsolete in this release have
3682 been commented out. Unless there is activity to revive these
3683 configurations, the next release of GDB will have their sources
3684 permanently REMOVED.
3686 * REMOVED configurations and files
3688 Altos 3068 m68*-altos-*
3689 Convex c1-*-*, c2-*-*
3691 ARM RISCix arm-*-* (as host)
3695 * GDB has been converted to ISO C.
3697 GDB's source code has been converted to ISO C. In particular, the
3698 sources are fully protoized, and rely on standard headers being
3703 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3705 * The MI enabled by default.
3707 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3708 revised and enabled by default. Packages which use GDB as a debugging
3709 engine behind a UI or another front end are encouraged to switch to
3710 using the GDB/MI interface, instead of the old annotations interface
3711 which is now deprecated.
3713 * Support for debugging Pascal programs.
3715 GDB now includes support for debugging Pascal programs. The following
3716 main features are supported:
3718 - Pascal-specific data types such as sets;
3720 - automatic recognition of Pascal sources based on file-name
3723 - Pascal-style display of data types, variables, and functions;
3725 - a Pascal expression parser.
3727 However, some important features are not yet supported.
3729 - Pascal string operations are not supported at all;
3731 - there are some problems with boolean types;
3733 - Pascal type hexadecimal constants are not supported
3734 because they conflict with the internal variables format;
3736 - support for Pascal objects and classes is not full yet;
3738 - unlike Pascal, GDB is case-sensitive for symbol names.
3740 * Changes in completion.
3742 Commands such as `shell', `run' and `set args', which pass arguments
3743 to inferior programs, now complete on file names, similar to what
3744 users expect at the shell prompt.
3746 Commands which accept locations, such as `disassemble', `print',
3747 `breakpoint', `until', etc. now complete on filenames as well as
3748 program symbols. Thus, if you type "break foob TAB", and the source
3749 files linked into the programs include `foobar.c', that file name will
3750 be one of the candidates for completion. However, file names are not
3751 considered for completion after you typed a colon that delimits a file
3752 name from a name of a function in that file, as in "break foo.c:bar".
3754 `set demangle-style' completes on available demangling styles.
3756 * New platform-independent commands:
3758 It is now possible to define a post-hook for a command as well as a
3759 hook that runs before the command. For more details, see the
3760 documentation of `hookpost' in the GDB manual.
3762 * Changes in GNU/Linux native debugging.
3764 Support for debugging multi-threaded programs has been completely
3765 revised for all platforms except m68k and sparc. You can now debug as
3766 many threads as your system allows you to have.
3768 Attach/detach is supported for multi-threaded programs.
3770 Support for SSE registers was added for x86. This doesn't work for
3771 multi-threaded programs though.
3773 * Changes in MIPS configurations.
3775 Multi-arch support is enabled for all MIPS configurations.
3777 GDB can now be built as native debugger on SGI Irix 6.x systems for
3778 debugging n32 executables. (Debugging 64-bit executables is not yet
3781 * Unified support for hardware watchpoints in all x86 configurations.
3783 Most (if not all) native x86 configurations support hardware-assisted
3784 breakpoints and watchpoints in a unified manner. This support
3785 implements debug register sharing between watchpoints, which allows to
3786 put a virtually infinite number of watchpoints on the same address,
3787 and also supports watching regions up to 16 bytes with several debug
3790 The new maintenance command `maintenance show-debug-regs' toggles
3791 debugging print-outs in functions that insert, remove, and test
3792 watchpoints and hardware breakpoints.
3794 * Changes in the DJGPP native configuration.
3796 New command ``info dos sysinfo'' displays assorted information about
3797 the CPU, OS, memory, and DPMI server.
3799 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3800 display information about segment descriptors stored in GDT, LDT, and
3803 New commands ``info dos pde'' and ``info dos pte'' display entries
3804 from Page Directory and Page Tables (for now works with CWSDPMI only).
3805 New command ``info dos address-pte'' displays the Page Table entry for
3806 a given linear address.
3808 GDB can now pass command lines longer than 126 characters to the
3809 program being debugged (requires an update to the libdbg.a library
3810 which is part of the DJGPP development kit).
3812 DWARF2 debug info is now supported.
3814 It is now possible to `step' and `next' through calls to `longjmp'.
3816 * Changes in documentation.
3818 All GDB documentation was converted to GFDL, the GNU Free
3819 Documentation License.
3821 Tracepoints-related commands are now fully documented in the GDB
3824 TUI, the Text-mode User Interface, is now documented in the manual.
3826 Tracepoints-related commands are now fully documented in the GDB
3829 The "GDB Internals" manual now has an index. It also includes
3830 documentation of `ui_out' functions, GDB coding standards, x86
3831 hardware watchpoints, and memory region attributes.
3833 * GDB's version number moved to ``version.in''
3835 The Makefile variable VERSION has been replaced by the file
3836 ``version.in''. People creating GDB distributions should update the
3837 contents of this file.
3841 GUD support is now a standard part of the EMACS distribution.
3843 *** Changes in GDB 5.0:
3845 * Improved support for debugging FP programs on x86 targets
3847 Unified and much-improved support for debugging floating-point
3848 programs on all x86 targets. In particular, ``info float'' now
3849 displays the FP registers in the same format on all x86 targets, with
3850 greater level of detail.
3852 * Improvements and bugfixes in hardware-assisted watchpoints
3854 It is now possible to watch array elements, struct members, and
3855 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3856 on x86 targets no longer erroneously trigger when the address is
3859 * Improvements in the native DJGPP version of GDB
3861 The distribution now includes all the scripts and auxiliary files
3862 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3863 machines ``out of the box''.
3865 The DJGPP version can now debug programs that use signals. It is
3866 possible to catch signals that happened in the debuggee, deliver
3867 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3868 would kill the program being debugged.) Programs that hook hardware
3869 interrupts (keyboard, timer, etc.) can also be debugged.
3871 It is now possible to debug DJGPP programs that redirect their
3872 standard handles or switch them to raw (as opposed to cooked) mode, or
3873 even close them. The command ``run < foo > bar'' works as expected,
3874 and ``info terminal'' reports useful information about the debuggee's
3875 terminal, including raw/cooked mode, redirection, etc.
3877 The DJGPP version now uses termios functions for console I/O, which
3878 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3881 DOS-style file names with drive letters are now fully supported by
3884 It is now possible to debug DJGPP programs that switch their working
3885 directory. It is also possible to rerun the debuggee any number of
3886 times without restarting GDB; thus, you can use the same setup,
3887 breakpoints, etc. for many debugging sessions.
3889 * New native configurations
3891 ARM GNU/Linux arm*-*-linux*
3892 PowerPC GNU/Linux powerpc-*-linux*
3896 Motorola MCore mcore-*-*
3897 x86 VxWorks i[3456]86-*-vxworks*
3898 PowerPC VxWorks powerpc-*-vxworks*
3899 TI TMS320C80 tic80-*-*
3901 * OBSOLETE configurations
3903 Altos 3068 m68*-altos-*
3904 Convex c1-*-*, c2-*-*
3906 ARM RISCix arm-*-* (as host)
3909 Configurations that have been declared obsolete will be commented out,
3910 but the code will be left in place. If there is no activity to revive
3911 these configurations before the next release of GDB, the sources will
3912 be permanently REMOVED.
3914 * Gould support removed
3916 Support for the Gould PowerNode and NP1 has been removed.
3918 * New features for SVR4
3920 On SVR4 native platforms (such as Solaris), if you attach to a process
3921 without first loading a symbol file, GDB will now attempt to locate and
3922 load symbols from the running process's executable file.
3924 * Many C++ enhancements
3926 C++ support has been greatly improved. Overload resolution now works properly
3927 in almost all cases. RTTI support is on the way.
3929 * Remote targets can connect to a sub-program
3931 A popen(3) style serial-device has been added. This device starts a
3932 sub-process (such as a stand-alone simulator) and then communicates
3933 with that. The sub-program to run is specified using the syntax
3934 ``|<program> <args>'' vis:
3936 (gdb) set remotedebug 1
3937 (gdb) target extended-remote |mn10300-elf-sim program-args
3939 * MIPS 64 remote protocol
3941 A long standing bug in the mips64 remote protocol where by GDB
3942 expected certain 32 bit registers (ex SR) to be transfered as 32
3943 instead of 64 bits has been fixed.
3945 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3946 added to provide backward compatibility with older versions of GDB.
3948 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3950 The command ``set remotebinarydownload'' command has been replaced by
3951 ``set remote X-packet''. Other commands in ``set remote'' family
3952 include ``set remote P-packet''.
3954 * Breakpoint commands accept ranges.
3956 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3957 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3958 ``tracepoint passcount'' also accepts a range of tracepoints.
3960 * ``apropos'' command added.
3962 The ``apropos'' command searches through command names and
3963 documentation strings, printing out matches, making it much easier to
3964 try to find a command that does what you are looking for.
3968 A new machine oriented interface (MI) has been added to GDB. This
3969 interface is designed for debug environments running GDB as a separate
3970 process. This is part of the long term libGDB project. See the
3971 "GDB/MI" chapter of the GDB manual for further information. It can be
3972 enabled by configuring with:
3974 .../configure --enable-gdbmi
3976 *** Changes in GDB-4.18:
3978 * New native configurations
3980 HP-UX 10.20 hppa*-*-hpux10.20
3981 HP-UX 11.x hppa*-*-hpux11.0*
3982 M68K GNU/Linux m68*-*-linux*
3986 Fujitsu FR30 fr30-*-elf*
3987 Intel StrongARM strongarm-*-*
3988 Mitsubishi D30V d30v-*-*
3990 * OBSOLETE configurations
3992 Gould PowerNode, NP1 np1-*-*, pn-*-*
3994 Configurations that have been declared obsolete will be commented out,
3995 but the code will be left in place. If there is no activity to revive
3996 these configurations before the next release of GDB, the sources will
3997 be permanently REMOVED.
4001 As a compatibility experiment, GDB's source files buildsym.h and
4002 buildsym.c have been converted to pure standard C, no longer
4003 containing any K&R compatibility code. We believe that all systems in
4004 use today either come with a standard C compiler, or have a GCC port
4005 available. If this is not true, please report the affected
4006 configuration to bug-gdb@gnu.org immediately. See the README file for
4007 information about getting a standard C compiler if you don't have one
4012 GDB now uses readline 2.2.
4014 * set extension-language
4016 You can now control the mapping between filename extensions and source
4017 languages by using the `set extension-language' command. For instance,
4018 you can ask GDB to treat .c files as C++ by saying
4019 set extension-language .c c++
4020 The command `info extensions' lists all of the recognized extensions
4021 and their associated languages.
4023 * Setting processor type for PowerPC and RS/6000
4025 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4026 you can use the `set processor' command to specify what variant of the
4027 PowerPC family you are debugging. The command
4031 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4032 following PowerPC and RS6000 variants:
4034 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4035 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4037 403GC IBM PowerPC 403GC
4038 505 Motorola PowerPC 505
4039 860 Motorola PowerPC 860 or 850
4040 601 Motorola PowerPC 601
4041 602 Motorola PowerPC 602
4042 603 Motorola/IBM PowerPC 603 or 603e
4043 604 Motorola PowerPC 604 or 604e
4044 750 Motorola/IBM PowerPC 750 or 750
4046 At the moment, this command just tells GDB what to name the
4047 special-purpose processor registers. Since almost all the affected
4048 registers are inaccessible to user-level programs, this command is
4049 only useful for remote debugging in its present form.
4053 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4054 more extensive support for HP-UX. Added features include shared
4055 library support, kernel threads and hardware watchpoints for 11.00,
4056 support for HP's ANSI C and C++ compilers, and a compatibility mode
4057 for xdb and dbx commands.
4061 HP's donation includes the new concept of catchpoints, which is a
4062 generalization of the old catch command. On HP-UX, it is now possible
4063 to catch exec, fork, and vfork, as well as library loading.
4065 This means that the existing catch command has changed; its first
4066 argument now specifies the type of catch to be set up. See the
4067 output of "help catch" for a list of catchpoint types.
4069 * Debugging across forks
4071 On HP-UX, you can choose which process to debug when a fork() happens
4076 HP has donated a curses-based terminal user interface (TUI). To get
4077 it, build with --enable-tui. Although this can be enabled for any
4078 configuration, at present it only works for native HP debugging.
4080 * GDB remote protocol additions
4082 A new protocol packet 'X' that writes binary data is now available.
4083 Default behavior is to try 'X', then drop back to 'M' if the stub
4084 fails to respond. The settable variable `remotebinarydownload'
4085 allows explicit control over the use of 'X'.
4087 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4088 full 64-bit address. The command
4090 set remoteaddresssize 32
4092 can be used to revert to the old behaviour. For existing remote stubs
4093 the change should not be noticed, as the additional address information
4096 In order to assist in debugging stubs, you may use the maintenance
4097 command `packet' to send any text string to the stub. For instance,
4099 maint packet heythere
4101 sends the packet "$heythere#<checksum>". Note that it is very easy to
4102 disrupt a debugging session by sending the wrong packet at the wrong
4105 The compare-sections command allows you to compare section data on the
4106 target to what is in the executable file without uploading or
4107 downloading, by comparing CRC checksums.
4109 * Tracing can collect general expressions
4111 You may now collect general expressions at tracepoints. This requires
4112 further additions to the target-side stub; see tracepoint.c and
4113 doc/agentexpr.texi for further details.
4115 * mask-address variable for Mips
4117 For Mips targets, you may control the zeroing of the upper 32 bits of
4118 a 64-bit address by entering `set mask-address on'. This is mainly
4119 of interest to users of embedded R4xxx and R5xxx processors.
4121 * Higher serial baud rates
4123 GDB's serial code now allows you to specify baud rates 57600, 115200,
4124 230400, and 460800 baud. (Note that your host system may not be able
4125 to achieve all of these rates.)
4129 The i960 configuration now includes an initial implementation of a
4130 builtin simulator, contributed by Jim Wilson.
4133 *** Changes in GDB-4.17:
4135 * New native configurations
4137 Alpha GNU/Linux alpha*-*-linux*
4138 Unixware 2.x i[3456]86-unixware2*
4139 Irix 6.x mips*-sgi-irix6*
4140 PowerPC GNU/Linux powerpc-*-linux*
4141 PowerPC Solaris powerpcle-*-solaris*
4142 Sparc GNU/Linux sparc-*-linux*
4143 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4147 Argonaut Risc Chip (ARC) arc-*-*
4148 Hitachi H8/300S h8300*-*-*
4149 Matsushita MN10200 w/simulator mn10200-*-*
4150 Matsushita MN10300 w/simulator mn10300-*-*
4151 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4152 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4153 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4154 Mitsubishi D10V w/simulator d10v-*-*
4155 Mitsubishi M32R/D w/simulator m32r-*-elf*
4156 Tsqware Sparclet sparclet-*-*
4157 NEC V850 w/simulator v850-*-*
4159 * New debugging protocols
4161 ARM with RDI protocol arm*-*-*
4162 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4163 DDB and LSI variants of PMON protocol mips*-*-*
4164 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4165 PowerPC with SDS protocol powerpc{,le}-*-eabi
4166 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4170 All configurations can now understand and use the DWARF 2 debugging
4171 format. The choice is automatic, if the symbol file contains DWARF 2
4176 GDB now includes basic Java language support. This support is
4177 only useful with Java compilers that produce native machine code.
4179 * solib-absolute-prefix and solib-search-path
4181 For SunOS and SVR4 shared libraries, you may now set the prefix for
4182 loading absolute shared library symbol files, and the search path for
4183 locating non-absolute shared library symbol files.
4185 * Live range splitting
4187 GDB can now effectively debug code for which GCC has performed live
4188 range splitting as part of its optimization. See gdb/doc/LRS for
4189 more details on the expected format of the stabs information.
4193 GDB's support for the GNU Hurd, including thread debugging, has been
4194 updated to work with current versions of the Hurd.
4198 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4199 instruction set. ARM GDB automatically detects when Thumb
4200 instructions are in use, and adjusts disassembly and backtracing
4205 GDB's MIPS target configurations now handle the MIP16 16-bit
4210 GDB now includes support for overlays; if an executable has been
4211 linked such that multiple sections are based at the same address, GDB
4212 will decide which section to use for symbolic info. You can choose to
4213 control the decision manually, using overlay commands, or implement
4214 additional target-side support and use "overlay load-target" to bring
4215 in the overlay mapping. Do "help overlay" for more detail.
4219 The command "info symbol <address>" displays information about
4220 the symbol at the specified address.
4224 The standard remote protocol now includes an extension that allows
4225 asynchronous collection and display of trace data. This requires
4226 extensive support in the target-side debugging stub. Tracing mode
4227 includes a new interaction mode in GDB and new commands: see the
4228 file tracepoint.c for more details.
4232 Configurations for embedded MIPS now include a simulator contributed
4233 by Cygnus Solutions. The simulator supports the instruction sets
4234 of most MIPS variants.
4238 Sparc configurations may now include the ERC32 simulator contributed
4239 by the European Space Agency. The simulator is not built into
4240 Sparc targets by default; configure with --enable-sim to include it.
4244 For target configurations that may include multiple variants of a
4245 basic architecture (such as MIPS and SH), you may now set the
4246 architecture explicitly. "set arch" sets, "info arch" lists
4247 the possible architectures.
4249 *** Changes in GDB-4.16:
4251 * New native configurations
4253 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4254 M68K NetBSD m68k-*-netbsd*
4255 PowerPC AIX 4.x powerpc-*-aix*
4256 PowerPC MacOS powerpc-*-macos*
4257 PowerPC Windows NT powerpcle-*-cygwin32
4258 RS/6000 AIX 4.x rs6000-*-aix4*
4262 ARM with RDP protocol arm-*-*
4263 I960 with MON960 i960-*-coff
4264 MIPS VxWorks mips*-*-vxworks*
4265 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4266 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4268 Matra Sparclet sparclet-*-*
4272 The powerpc-eabi configuration now includes the PSIM simulator,
4273 contributed by Andrew Cagney, with assistance from Mike Meissner.
4274 PSIM is a very elaborate model of the PowerPC, including not only
4275 basic instruction set execution, but also details of execution unit
4276 performance and I/O hardware. See sim/ppc/README for more details.
4280 GDB now works with Solaris 2.5.
4282 * Windows 95/NT native
4284 GDB will now work as a native debugger on Windows 95 and Windows NT.
4285 To build it from source, you must use the "gnu-win32" environment,
4286 which uses a DLL to emulate enough of Unix to run the GNU tools.
4287 Further information, binaries, and sources are available at
4288 ftp.cygnus.com, under pub/gnu-win32.
4290 * dont-repeat command
4292 If a user-defined command includes the command `dont-repeat', then the
4293 command will not be repeated if the user just types return. This is
4294 useful if the command is time-consuming to run, so that accidental
4295 extra keystrokes don't run the same command many times.
4297 * Send break instead of ^C
4299 The standard remote protocol now includes an option to send a break
4300 rather than a ^C to the target in order to interrupt it. By default,
4301 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4303 * Remote protocol timeout
4305 The standard remote protocol includes a new variable `remotetimeout'
4306 that allows you to set the number of seconds before GDB gives up trying
4307 to read from the target. The default value is 2.
4309 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4311 By default GDB will automatically keep track of objects as they are
4312 loaded and unloaded by the dynamic linker. By using the command `set
4313 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4314 when shared library events occur, thus allowing you to set breakpoints
4315 in shared libraries which are explicitly loaded by the inferior.
4317 Note this feature does not work on hpux8. On hpux9 you must link
4318 /usr/lib/end.o into your program. This feature should work
4319 automatically on hpux10.
4321 * Irix 5.x hardware watchpoint support
4323 Irix 5 configurations now support the use of hardware watchpoints.
4325 * Mips protocol "SYN garbage limit"
4327 When debugging a Mips target using the `target mips' protocol, you
4328 may set the number of characters that GDB will ignore by setting
4329 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4330 every character. The default value is 1050.
4332 * Recording and replaying remote debug sessions
4334 If you set `remotelogfile' to the name of a file, gdb will write to it
4335 a recording of a remote debug session. This recording may then be
4336 replayed back to gdb using "gdbreplay". See gdbserver/README for
4337 details. This is useful when you have a problem with GDB while doing
4338 remote debugging; you can make a recording of the session and send it
4339 to someone else, who can then recreate the problem.
4341 * Speedups for remote debugging
4343 GDB includes speedups for downloading and stepping MIPS systems using
4344 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4345 and more efficient S-record downloading.
4347 * Memory use reductions and statistics collection
4349 GDB now uses less memory and reports statistics about memory usage.
4350 Try the `maint print statistics' command, for example.
4352 *** Changes in GDB-4.15:
4354 * Psymtabs for XCOFF
4356 The symbol reader for AIX GDB now uses partial symbol tables. This
4357 can greatly improve startup time, especially for large executables.
4359 * Remote targets use caching
4361 Remote targets now use a data cache to speed up communication with the
4362 remote side. The data cache could lead to incorrect results because
4363 it doesn't know about volatile variables, thus making it impossible to
4364 debug targets which use memory mapped I/O devices. `set remotecache
4365 off' turns the the data cache off.
4367 * Remote targets may have threads
4369 The standard remote protocol now includes support for multiple threads
4370 in the target system, using new protocol commands 'H' and 'T'. See
4371 gdb/remote.c for details.
4375 If GDB is configured with `--enable-netrom', then it will include
4376 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4377 acts as though it is a bank of ROM on the target board, but you can
4378 write into it over the network. GDB's support consists only of
4379 support for fast loading into the emulated ROM; to debug, you must use
4380 another protocol, such as standard remote protocol. The usual
4381 sequence is something like
4383 target nrom <netrom-hostname>
4385 target remote <netrom-hostname>:1235
4389 GDB now includes support for the Apple Macintosh, as a host only. It
4390 may be run as either an MPW tool or as a standalone application, and
4391 it can debug through the serial port. All the usual GDB commands are
4392 available, but to the target command, you must supply "serial" as the
4393 device type instead of "/dev/ttyXX". See mpw-README in the main
4394 directory for more information on how to build. The MPW configuration
4395 scripts */mpw-config.in support only a few targets, and only the
4396 mips-idt-ecoff target has been tested.
4400 GDB configuration now uses autoconf. This is not user-visible,
4401 but does simplify configuration and building.
4405 GDB now supports hpux10.
4407 *** Changes in GDB-4.14:
4409 * New native configurations
4411 x86 FreeBSD i[345]86-*-freebsd
4412 x86 NetBSD i[345]86-*-netbsd
4413 NS32k NetBSD ns32k-*-netbsd
4414 Sparc NetBSD sparc-*-netbsd
4418 A29K VxWorks a29k-*-vxworks
4419 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4420 CPU32 EST-300 emulator m68*-*-est*
4421 PowerPC ELF powerpc-*-elf
4424 * Alpha OSF/1 support for procfs
4426 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4427 possible to attach to running processes. As the mounting of the /proc
4428 filesystem is optional on the Alpha, GDB automatically determines
4429 the availability of /proc during startup. This can lead to problems
4430 if /proc is unmounted after GDB has been started.
4432 * Arguments to user-defined commands
4434 User commands may accept up to 10 arguments separated by whitespace.
4435 Arguments are accessed within the user command via $arg0..$arg9. A
4438 print $arg0 + $arg1 + $arg2
4440 To execute the command use:
4443 Defines the command "adder" which prints the sum of its three arguments.
4444 Note the arguments are text substitutions, so they may reference variables,
4445 use complex expressions, or even perform inferior function calls.
4447 * New `if' and `while' commands
4449 This makes it possible to write more sophisticated user-defined
4450 commands. Both commands take a single argument, which is the
4451 expression to evaluate, and must be followed by the commands to
4452 execute, one per line, if the expression is nonzero, the list being
4453 terminated by the word `end'. The `if' command list may include an
4454 `else' word, which causes the following commands to be executed only
4455 if the expression is zero.
4457 * Fortran source language mode
4459 GDB now includes partial support for Fortran 77. It will recognize
4460 Fortran programs and can evaluate a subset of Fortran expressions, but
4461 variables and functions may not be handled correctly. GDB will work
4462 with G77, but does not yet know much about symbols emitted by other
4465 * Better HPUX support
4467 Most debugging facilities now work on dynamic executables for HPPAs
4468 running hpux9 or later. You can attach to running dynamically linked
4469 processes, but by default the dynamic libraries will be read-only, so
4470 for instance you won't be able to put breakpoints in them. To change
4471 that behavior do the following before running the program:
4477 This will cause the libraries to be mapped private and read-write.
4478 To revert to the normal behavior, do this:
4484 You cannot set breakpoints or examine data in the library until after
4485 the library is loaded if the function/data symbols do not have
4488 GDB can now also read debug symbols produced by the HP C compiler on
4489 HPPAs (sorry, no C++, Fortran or 68k support).
4491 * Target byte order now dynamically selectable
4493 You can choose which byte order to use with a target system, via the
4494 commands "set endian big" and "set endian little", and you can see the
4495 current setting by using "show endian". You can also give the command
4496 "set endian auto", in which case GDB will use the byte order
4497 associated with the executable. Currently, only embedded MIPS
4498 configurations support dynamic selection of target byte order.
4500 * New DOS host serial code
4502 This version uses DPMI interrupts to handle buffered I/O, so you
4503 no longer need to run asynctsr when debugging boards connected to
4506 *** Changes in GDB-4.13:
4508 * New "complete" command
4510 This lists all the possible completions for the rest of the line, if it
4511 were to be given as a command itself. This is intended for use by emacs.
4513 * Trailing space optional in prompt
4515 "set prompt" no longer adds a space for you after the prompt you set. This
4516 allows you to set a prompt which ends in a space or one that does not.
4518 * Breakpoint hit counts
4520 "info break" now displays a count of the number of times the breakpoint
4521 has been hit. This is especially useful in conjunction with "ignore"; you
4522 can ignore a large number of breakpoint hits, look at the breakpoint info
4523 to see how many times the breakpoint was hit, then run again, ignoring one
4524 less than that number, and this will get you quickly to the last hit of
4527 * Ability to stop printing at NULL character
4529 "set print null-stop" will cause GDB to stop printing the characters of
4530 an array when the first NULL is encountered. This is useful when large
4531 arrays actually contain only short strings.
4533 * Shared library breakpoints
4535 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4536 breakpoints in shared libraries before the executable is run.
4538 * Hardware watchpoints
4540 There is a new hardware breakpoint for the watch command for sparclite
4541 targets. See gdb/sparclite/hw_breakpoint.note.
4543 Hardware watchpoints are also now supported under GNU/Linux.
4547 Annotations have been added. These are for use with graphical interfaces,
4548 and are still experimental. Currently only gdba.el uses these.
4550 * Improved Irix 5 support
4552 GDB now works properly with Irix 5.2.
4554 * Improved HPPA support
4556 GDB now works properly with the latest GCC and GAS.
4558 * New native configurations
4560 Sequent PTX4 i[34]86-sequent-ptx4
4561 HPPA running OSF/1 hppa*-*-osf*
4562 Atari TT running SVR4 m68*-*-sysv4*
4563 RS/6000 LynxOS rs6000-*-lynxos*
4567 OS/9000 i[34]86-*-os9k
4568 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4571 * Hitachi SH7000 and E7000-PC ICE support
4573 There is now support for communicating with the Hitachi E7000-PC ICE.
4574 This is available automatically when GDB is configured for the SH.
4578 As usual, a variety of small fixes and improvements, both generic
4579 and configuration-specific. See the ChangeLog for more detail.
4581 *** Changes in GDB-4.12:
4583 * Irix 5 is now supported
4587 GDB-4.12 on the HPPA has a number of changes which make it unable
4588 to debug the output from the currently released versions of GCC and
4589 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4590 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4591 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4594 *** Changes in GDB-4.11:
4596 * User visible changes:
4600 The "set remotedebug" option is now consistent between the mips remote
4601 target, remote targets using the gdb-specific protocol, UDI (AMD's
4602 debug protocol for the 29k) and the 88k bug monitor. It is now an
4603 integer specifying a debug level (normally 0 or 1, but 2 means more
4604 debugging info for the mips target).
4606 * DEC Alpha native support
4608 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4609 debug info, but GDB works fairly well with the DEC compiler and should
4610 work with a future GCC release. See the README file for a few
4611 Alpha-specific notes.
4613 * Preliminary thread implementation
4615 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4617 * LynxOS native and target support for 386
4619 This release has been hosted on LynxOS 2.2, and also can be configured
4620 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4623 * Improvements in C++ mangling/demangling.
4625 This release has much better g++ debugging, specifically in name
4626 mangling/demangling, virtual function calls, print virtual table,
4627 call methods, ...etc.
4629 *** Changes in GDB-4.10:
4631 * User visible changes:
4633 Remote debugging using the GDB-specific (`target remote') protocol now
4634 supports the `load' command. This is only useful if you have some
4635 other way of getting the stub to the target system, and you can put it
4636 somewhere in memory where it won't get clobbered by the download.
4638 Filename completion now works.
4640 When run under emacs mode, the "info line" command now causes the
4641 arrow to point to the line specified. Also, "info line" prints
4642 addresses in symbolic form (as well as hex).
4644 All vxworks based targets now support a user settable option, called
4645 vxworks-timeout. This option represents the number of seconds gdb
4646 should wait for responses to rpc's. You might want to use this if
4647 your vxworks target is, perhaps, a slow software simulator or happens
4648 to be on the far side of a thin network line.
4652 This release contains support for using a DEC alpha as a GDB host for
4653 cross debugging. Native alpha debugging is not supported yet.
4656 *** Changes in GDB-4.9:
4660 This is the first GDB release which is accompanied by a matching testsuite.
4661 The testsuite requires installation of dejagnu, which should be available
4662 via ftp from most sites that carry GNU software.
4666 'Cfront' style demangling has had its name changed to 'ARM' style, to
4667 emphasize that it was written from the specifications in the C++ Annotated
4668 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4669 disclaimers, it still generated too much confusion with users attempting to
4670 use gdb with AT&T cfront.
4674 GDB now uses a standard remote interface to a simulator library.
4675 So far, the library contains simulators for the Zilog Z8001/2, the
4676 Hitachi H8/300, H8/500 and Super-H.
4678 * New targets supported
4680 H8/300 simulator h8300-hitachi-hms or h8300hms
4681 H8/500 simulator h8500-hitachi-hms or h8500hms
4682 SH simulator sh-hitachi-hms or sh
4683 Z8000 simulator z8k-zilog-none or z8ksim
4684 IDT MIPS board over serial line mips-idt-ecoff
4686 Cross-debugging to GO32 targets is supported. It requires a custom
4687 version of the i386-stub.c module which is integrated with the
4688 GO32 memory extender.
4690 * New remote protocols
4692 MIPS remote debugging protocol.
4694 * New source languages supported
4696 This version includes preliminary support for Chill, a Pascal like language
4697 used by telecommunications companies. Chill support is also being integrated
4698 into the GNU compiler, but we don't know when it will be publically available.
4701 *** Changes in GDB-4.8:
4703 * HP Precision Architecture supported
4705 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4706 version of this support was available as a set of patches from the
4707 University of Utah. GDB does not support debugging of programs
4708 compiled with the HP compiler, because HP will not document their file
4709 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4710 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4712 Many problems in the preliminary version have been fixed.
4714 * Faster and better demangling
4716 We have improved template demangling and fixed numerous bugs in the GNU style
4717 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4718 character types (wchar_t) are now supported. Demangling of each symbol is now
4719 only done once, and is cached when the symbol table for a file is read in.
4720 This results in a small increase in memory usage for C programs, a moderate
4721 increase in memory usage for C++ programs, and a fantastic speedup in
4724 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4725 from the specifications in the Annotated Reference Manual, which AT&T's
4726 compiler does not actually implement.
4728 * G++ multiple inheritance compiler problem
4730 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4731 inheritance lattices was reworked to properly discover ambiguities. We
4732 recently found an example which causes this new algorithm to fail in a
4733 very subtle way, producing bad debug information for those classes.
4734 The file 'gcc.patch' (in this directory) can be applied to gcc to
4735 circumvent the problem. A future GCC release will contain a complete
4738 The previous G++ debug info problem (mentioned below for the gdb-4.7
4739 release) is fixed in gcc version 2.3.2.
4741 * Improved configure script
4743 The `configure' script will now attempt to guess your system type if
4744 you don't supply a host system type. The old scheme of supplying a
4745 host system triplet is preferable over using this. All the magic is
4746 done in the new `config.guess' script. Examine it for details.
4748 We have also brought our configure script much more in line with the FSF's
4749 version. It now supports the --with-xxx options. In particular,
4750 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4751 The resulting GDB will not be able to read arbitrary object file formats --
4752 only the format ``expected'' to be used on the configured target system.
4753 We hope to make this the default in a future release.
4755 * Documentation improvements
4757 There's new internal documentation on how to modify GDB, and how to
4758 produce clean changes to the code. We implore people to read it
4759 before submitting changes.
4761 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4762 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4763 `info' files are also provided. To build `info' files from scratch,
4764 you will need the latest `makeinfo' release, which will be available in
4765 a future texinfo-X.Y release.
4767 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4768 We're not sure exactly which versions have this problem, but it has
4769 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4770 or better. If that isn't possible, there is a patch in
4771 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4772 around this problem.
4776 GDB now supports array constants that can be used in expressions typed in by
4777 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4778 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4781 The new directory `gdb/sparclite' contains a program that demonstrates
4782 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4784 * New native hosts supported
4786 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4787 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4789 * New targets supported
4791 AMD 29k family via UDI a29k-amd-udi or udi29k
4793 * New file formats supported
4795 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4796 HPUX core files, and SCO 3.2v2 core files.
4800 Attaching to processes now works again; thanks for the many bug reports.
4802 We have also stomped on a bunch of core dumps caused by
4803 printf_filtered("%s") problems.
4805 We eliminated a copyright problem on the rpc and ptrace header files
4806 for VxWorks, which was discovered at the last minute during the 4.7
4807 release. You should now be able to build a VxWorks GDB.
4809 You can now interrupt gdb while an attached process is running. This
4810 will cause the attached process to stop, and give control back to GDB.
4812 We fixed problems caused by using too many file descriptors
4813 for reading symbols from object files and libraries. This was
4814 especially a problem for programs that used many (~100) shared
4817 The `step' command now only enters a subroutine if there is line number
4818 information for the subroutine. Otherwise it acts like the `next'
4819 command. Previously, `step' would enter subroutines if there was
4820 any debugging information about the routine. This avoids problems
4821 when using `cc -g1' on MIPS machines.
4823 * Internal improvements
4825 GDB's internal interfaces have been improved to make it easier to support
4826 debugging of multiple languages in the future.
4828 GDB now uses a common structure for symbol information internally.
4829 Minimal symbols (derived from linkage symbols in object files), partial
4830 symbols (from a quick scan of debug information), and full symbols
4831 contain a common subset of information, making it easier to write
4832 shared code that handles any of them.
4834 * New command line options
4836 We now accept --silent as an alias for --quiet.
4840 The memory-mapped-malloc library is now licensed under the GNU Library
4841 General Public License.
4843 *** Changes in GDB-4.7:
4845 * Host/native/target split
4847 GDB has had some major internal surgery to untangle the support for
4848 hosts and remote targets. Now, when you configure GDB for a remote
4849 target, it will no longer load in all of the support for debugging
4850 local programs on the host. When fully completed and tested, this will
4851 ensure that arbitrary host/target combinations are possible.
4853 The primary conceptual shift is to separate the non-portable code in
4854 GDB into three categories. Host specific code is required any time GDB
4855 is compiled on that host, regardless of the target. Target specific
4856 code relates to the peculiarities of the target, but can be compiled on
4857 any host. Native specific code is everything else: it can only be
4858 built when the host and target are the same system. Child process
4859 handling and core file support are two common `native' examples.
4861 GDB's use of /proc for controlling Unix child processes is now cleaner.
4862 It has been split out into a single module under the `target_ops' vector,
4863 plus two native-dependent functions for each system that uses /proc.
4865 * New hosts supported
4867 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4868 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4869 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4871 * New targets supported
4873 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4874 68030 and CPU32 m68030-*-*, m68332-*-*
4876 * New native hosts supported
4878 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4879 (386bsd is not well tested yet)
4880 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4882 * New file formats supported
4884 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4885 supports reading of `a.out.adobe' object files, which are an a.out
4886 format extended with minimal information about multiple sections.
4890 `show copying' is the same as the old `info copying'.
4891 `show warranty' is the same as `info warrantee'.
4892 These were renamed for consistency. The old commands continue to work.
4894 `info handle' is a new alias for `info signals'.
4896 You can now define pre-command hooks, which attach arbitrary command
4897 scripts to any command. The commands in the hook will be executed
4898 prior to the user's command. You can also create a hook which will be
4899 executed whenever the program stops. See gdb.texinfo.
4903 We now deal with Cfront style name mangling, and can even extract type
4904 info from mangled symbols. GDB can automatically figure out which
4905 symbol mangling style your C++ compiler uses.
4907 Calling of methods and virtual functions has been improved as well.
4911 The crash that occured when debugging Sun Ansi-C compiled binaries is
4912 fixed. This was due to mishandling of the extra N_SO stabs output
4915 We also finally got Ultrix 4.2 running in house, and fixed core file
4916 support, with help from a dozen people on the net.
4918 John M. Farrell discovered that the reason that single-stepping was so
4919 slow on all of the Mips based platforms (primarily SGI and DEC) was
4920 that we were trying to demangle and lookup a symbol used for internal
4921 purposes on every instruction that was being stepped through. Changing
4922 the name of that symbol so that it couldn't be mistaken for a C++
4923 mangled symbol sped things up a great deal.
4925 Rich Pixley sped up symbol lookups in general by getting much smarter
4926 about when C++ symbol mangling is necessary. This should make symbol
4927 completion (TAB on the command line) much faster. It's not as fast as
4928 we'd like, but it's significantly faster than gdb-4.6.
4932 A new user controllable variable 'call_scratch_address' can
4933 specify the location of a scratch area to be used when GDB
4934 calls a function in the target. This is necessary because the
4935 usual method of putting the scratch area on the stack does not work
4936 in systems that have separate instruction and data spaces.
4938 We integrated changes to support the 29k UDI (Universal Debugger
4939 Interface), but discovered at the last minute that we didn't have all
4940 of the appropriate copyright paperwork. We are working with AMD to
4941 resolve this, and hope to have it available soon.
4945 We have sped up the remote serial line protocol, especially for targets
4946 with lots of registers. It now supports a new `expedited status' ('T')
4947 message which can be used in place of the existing 'S' status message.
4948 This allows the remote stub to send only the registers that GDB
4949 needs to make a quick decision about single-stepping or conditional
4950 breakpoints, eliminating the need to fetch the entire register set for
4951 each instruction being stepped through.
4953 The GDB remote serial protocol now implements a write-through cache for
4954 registers, only re-reading the registers if the target has run.
4956 There is also a new remote serial stub for SPARC processors. You can
4957 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4958 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4959 processor with a serial port.
4963 Configure.in files have become much easier to read and modify. A new
4964 `table driven' format makes it more obvious what configurations are
4965 supported, and what files each one uses.
4969 There is a new opcodes library which will eventually contain all of the
4970 disassembly routines and opcode tables. At present, it only contains
4971 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4972 disassembler (binutils/objdump) to share these routines.
4974 The libiberty library is now copylefted under the GNU Library General
4975 Public License. This allows more liberal use, and was done so libg++
4976 can use it. This makes no difference to GDB, since the Library License
4977 grants all the rights from the General Public License.
4981 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4982 reference to the stabs symbol info used by the debugger. It is (as far
4983 as we know) the only published document on this fascinating topic. We
4984 encourage you to read it, compare it to the stabs information on your
4985 system, and send improvements on the document in general (to
4986 bug-gdb@prep.ai.mit.edu).
4988 And, of course, many bugs have been fixed.
4991 *** Changes in GDB-4.6:
4993 * Better support for C++ function names
4995 GDB now accepts as input the "demangled form" of C++ overloaded function
4996 names and member function names, and can do command completion on such names
4997 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4998 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4999 Make use of command completion, it is your friend.
5001 GDB also now accepts a variety of C++ mangled symbol formats. They are
5002 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5003 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5004 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5005 for the list of formats.
5007 * G++ symbol mangling problem
5009 Recent versions of gcc have a bug in how they emit debugging information for
5010 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5011 directory) can be applied to gcc to fix the problem. Alternatively, if you
5012 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5013 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5014 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5017 * New 'maintenance' command
5019 All of the commands related to hacking GDB internals have been moved out of
5020 the main command set, and now live behind the 'maintenance' command. This
5021 can also be abbreviated as 'mt'. The following changes were made:
5023 dump-me -> maintenance dump-me
5024 info all-breakpoints -> maintenance info breakpoints
5025 printmsyms -> maintenance print msyms
5026 printobjfiles -> maintenance print objfiles
5027 printpsyms -> maintenance print psymbols
5028 printsyms -> maintenance print symbols
5030 The following commands are new:
5032 maintenance demangle Call internal GDB demangler routine to
5033 demangle a C++ link name and prints the result.
5034 maintenance print type Print a type chain for a given symbol
5036 * Change to .gdbinit file processing
5038 We now read the $HOME/.gdbinit file before processing the argv arguments
5039 (e.g. reading symbol files or core files). This allows global parameters to
5040 be set, which will apply during the symbol reading. The ./.gdbinit is still
5041 read after argv processing.
5043 * New hosts supported
5045 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5047 GNU/Linux support i386-unknown-linux or linux
5049 We are also including code to support the HP/PA running BSD and HPUX. This
5050 is almost guaranteed not to work, as we didn't have time to test or build it
5051 for this release. We are including it so that the more adventurous (or
5052 masochistic) of you can play with it. We also had major problems with the
5053 fact that the compiler that we got from HP doesn't support the -g option.
5056 * New targets supported
5058 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5060 * More smarts about finding #include files
5062 GDB now remembers the compilation directory for all include files, and for
5063 all files from which C is generated (like yacc and lex sources). This
5064 greatly improves GDB's ability to find yacc/lex sources, and include files,
5065 especially if you are debugging your program from a directory different from
5066 the one that contains your sources.
5068 We also fixed a bug which caused difficulty with listing and setting
5069 breakpoints in include files which contain C code. (In the past, you had to
5070 try twice in order to list an include file that you hadn't looked at before.)
5072 * Interesting infernals change
5074 GDB now deals with arbitrary numbers of sections, where the symbols for each
5075 section must be relocated relative to that section's landing place in the
5076 target's address space. This work was needed to support ELF with embedded
5077 stabs used by Solaris-2.0.
5079 * Bug fixes (of course!)
5081 There have been loads of fixes for the following things:
5082 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5083 i960, stabs, DOS(GO32), procfs, etc...
5085 See the ChangeLog for details.
5087 *** Changes in GDB-4.5:
5089 * New machines supported (host and target)
5091 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5093 SGI Irix-4.x mips-sgi-irix4 or iris4
5095 * New malloc package
5097 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5098 Mmalloc is capable of handling mutiple heaps of memory. It is also
5099 capable of saving a heap to a file, and then mapping it back in later.
5100 This can be used to greatly speedup the startup of GDB by using a
5101 pre-parsed symbol table which lives in a mmalloc managed heap. For
5102 more details, please read mmalloc/mmalloc.texi.
5106 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5107 'help info proc' for details.
5109 * MIPS ecoff symbol table format
5111 The code that reads MIPS symbol table format is now supported on all hosts.
5112 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5115 * File name changes for MS-DOS
5117 Many files in the config directories have been renamed to make it easier to
5118 support GDB on MS-DOSe systems (which have very restrictive file name
5119 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5120 environment) is close to working but has some remaining problems. Note
5121 that debugging of DOS programs is not supported, due to limitations
5122 in the ``operating system'', but it can be used to host cross-debugging.
5124 * Cross byte order fixes
5126 Many fixes have been made to support cross debugging of Sparc and MIPS
5127 targets from hosts whose byte order differs.
5129 * New -mapped and -readnow options
5131 If memory-mapped files are available on your system through the 'mmap'
5132 system call, you can use the -mapped option on the `file' or
5133 `symbol-file' commands to cause GDB to write the symbols from your
5134 program into a reusable file. If the program you are debugging is
5135 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5136 Future GDB debugging sessions will notice the presence of this file,
5137 and will quickly map in symbol information from it, rather than reading
5138 the symbol table from the executable program. Using the '-mapped'
5139 option in a GDB `file' or `symbol-file' command has the same effect as
5140 starting GDB with the '-mapped' command-line option.
5142 You can cause GDB to read the entire symbol table immediately by using
5143 the '-readnow' option with any of the commands that load symbol table
5144 information (or on the GDB command line). This makes the command
5145 slower, but makes future operations faster.
5147 The -mapped and -readnow options are typically combined in order to
5148 build a `fred.syms' file that contains complete symbol information.
5149 A simple GDB invocation to do nothing but build a `.syms' file for future
5152 gdb -batch -nx -mapped -readnow programname
5154 The `.syms' file is specific to the host machine on which GDB is run.
5155 It holds an exact image of GDB's internal symbol table. It cannot be
5156 shared across multiple host platforms.
5158 * longjmp() handling
5160 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5161 siglongjmp() without losing control. This feature has not yet been ported to
5162 all systems. It currently works on many 386 platforms, all MIPS-based
5163 platforms (SGI, DECstation, etc), and Sun3/4.
5167 Preliminary work has been put in to support the new Solaris OS from Sun. At
5168 this time, it can control and debug processes, but it is not capable of
5173 As always, many many bug fixes. The major areas were with g++, and mipsread.
5174 People using the MIPS-based platforms should experience fewer mysterious
5175 crashes and trashed symbol tables.
5177 *** Changes in GDB-4.4:
5179 * New machines supported (host and target)
5181 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5183 BSD Reno on Vax vax-dec-bsd
5184 Ultrix on Vax vax-dec-ultrix
5186 * New machines supported (target)
5188 AMD 29000 embedded, using EBMON a29k-none-none
5192 GDB continues to improve its handling of C++. `References' work better.
5193 The demangler has also been improved, and now deals with symbols mangled as
5194 per the Annotated C++ Reference Guide.
5196 GDB also now handles `stabs' symbol information embedded in MIPS
5197 `ecoff' symbol tables. Since the ecoff format was not easily
5198 extensible to handle new languages such as C++, this appeared to be a
5199 good way to put C++ debugging info into MIPS binaries. This option
5200 will be supported in the GNU C compiler, version 2, when it is
5203 * New features for SVR4
5205 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5206 shared libraries. Debugging dynamically linked programs should present
5207 only minor differences from debugging statically linked programs.
5209 The `info proc' command will print out information about any process
5210 on an SVR4 system (including the one you are debugging). At the moment,
5211 it prints the address mappings of the process.
5213 If you bring up GDB on another SVR4 system, please send mail to
5214 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5216 * Better dynamic linking support in SunOS
5218 Reading symbols from shared libraries which contain debugging symbols
5219 now works properly. However, there remain issues such as automatic
5220 skipping of `transfer vector' code during function calls, which
5221 make it harder to debug code in a shared library, than to debug the
5222 same code linked statically.
5226 GDB is now using the latest `getopt' routines from the FSF. This
5227 version accepts the -- prefix for options with long names. GDB will
5228 continue to accept the old forms (-option and +option) as well.
5229 Various single letter abbreviations for options have been explicity
5230 added to the option table so that they won't get overshadowed in the
5231 future by other options that begin with the same letter.
5235 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5236 Many assorted bugs have been handled. Many more remain to be handled.
5237 See the various ChangeLog files (primarily in gdb and bfd) for details.
5240 *** Changes in GDB-4.3:
5242 * New machines supported (host and target)
5244 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5245 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5246 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5248 * Almost SCO Unix support
5250 We had hoped to support:
5251 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5252 (except for core file support), but we discovered very late in the release
5253 that it has problems with process groups that render gdb unusable. Sorry
5254 about that. I encourage people to fix it and post the fixes.
5256 * Preliminary ELF and DWARF support
5258 GDB can read ELF object files on System V Release 4, and can handle
5259 debugging records for C, in DWARF format, in ELF files. This support
5260 is preliminary. If you bring up GDB on another SVR4 system, please
5261 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5266 GDB now uses the latest `readline' library. One user-visible change
5267 is that two tabs will list possible command completions, which previously
5268 required typing M-? (meta-question mark, or ESC ?).
5272 The `stepi' bug that many of you noticed has been squashed.
5273 Many bugs in C++ have been handled. Many more remain to be handled.
5274 See the various ChangeLog files (primarily in gdb and bfd) for details.
5276 * State of the MIPS world (in case you wondered):
5278 GDB can understand the symbol tables emitted by the compilers
5279 supplied by most vendors of MIPS-based machines, including DEC. These
5280 symbol tables are in a format that essentially nobody else uses.
5282 Some versions of gcc come with an assembler post-processor called
5283 mips-tfile. This program is required if you want to do source-level
5284 debugging of gcc-compiled programs. I believe FSF does not ship
5285 mips-tfile with gcc version 1, but it will eventually come with gcc
5288 Debugging of g++ output remains a problem. g++ version 1.xx does not
5289 really support it at all. (If you're lucky, you should be able to get
5290 line numbers and stack traces to work, but no parameters or local
5291 variables.) With some work it should be possible to improve the
5294 When gcc version 2 is released, you will have somewhat better luck.
5295 However, even then you will get confusing results for inheritance and
5298 We will eventually provide full debugging of g++ output on
5299 DECstations. This will probably involve some kind of stabs-in-ecoff
5300 encapulation, but the details have not been worked out yet.
5303 *** Changes in GDB-4.2:
5305 * Improved configuration
5307 Only one copy of `configure' exists now, and it is not self-modifying.
5308 Porting BFD is simpler.
5312 The `step' and `next' commands now only stop at the first instruction
5313 of a source line. This prevents the multiple stops that used to occur
5314 in switch statements, for-loops, etc. `Step' continues to stop if a
5315 function that has debugging information is called within the line.
5319 Lots of small bugs fixed. More remain.
5321 * New host supported (not target)
5323 Intel 386 PC clone running Mach i386-none-mach
5326 *** Changes in GDB-4.1:
5328 * Multiple source language support
5330 GDB now has internal scaffolding to handle several source languages.
5331 It determines the type of each source file from its filename extension,
5332 and will switch expression parsing and number formatting to match the
5333 language of the function in the currently selected stack frame.
5334 You can also specifically set the language to be used, with
5335 `set language c' or `set language modula-2'.
5339 GDB now has preliminary support for the GNU Modula-2 compiler,
5340 currently under development at the State University of New York at
5341 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5342 continue through the fall of 1991 and into 1992.
5344 Other Modula-2 compilers are currently not supported, and attempting to
5345 debug programs compiled with them will likely result in an error as the
5346 symbol table is read. Feel free to work on it, though!
5348 There are hooks in GDB for strict type checking and range checking,
5349 in the `Modula-2 philosophy', but they do not currently work.
5353 GDB can now write to executable and core files (e.g. patch
5354 a variable's value). You must turn this switch on, specify
5355 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5356 by assigning a new value to a variable. Modifications take
5359 * Automatic SunOS shared library reading
5361 When you run your program, GDB automatically determines where its
5362 shared libraries (if any) have been loaded, and reads their symbols.
5363 The `share' command is no longer needed. This also works when
5364 examining core files.
5368 You can specify the number of lines that the `list' command shows.
5371 * New machines supported (host and target)
5373 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5374 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5375 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5377 * New hosts supported (not targets)
5379 IBM RT/PC: romp-ibm-aix or rtpc
5381 * New targets supported (not hosts)
5383 AMD 29000 embedded with COFF a29k-none-coff
5384 AMD 29000 embedded with a.out a29k-none-aout
5385 Ultracomputer remote kernel debug a29k-nyu-kern
5387 * New remote interfaces
5393 *** Changes in GDB-4.0:
5397 Wide output is wrapped at good places to make the output more readable.
5399 Gdb now supports cross-debugging from a host machine of one type to a
5400 target machine of another type. Communication with the target system
5401 is over serial lines. The ``target'' command handles connecting to the
5402 remote system; the ``load'' command will download a program into the
5403 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5404 also supports debugging of realtime processes running under VxWorks,
5405 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5406 stub on the target system.
5408 New CPUs supported include the AMD 29000 and Intel 960.
5410 GDB now reads object files and symbol tables via a ``binary file''
5411 library, which allows a single copy of GDB to debug programs of multiple
5412 object file types such as a.out and coff.
5414 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5415 refcard.dvi and refcard.ps are available to format it).
5418 * Control-Variable user interface simplified
5420 All variables that control the operation of the debugger can be set
5421 by the ``set'' command, and displayed by the ``show'' command.
5423 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5424 ``Show prompt'' produces the response:
5425 Gdb's prompt is new-gdb=>.
5427 What follows are the NEW set commands. The command ``help set'' will
5428 print a complete list of old and new set commands. ``help set FOO''
5429 will give a longer description of the variable FOO. ``show'' will show
5430 all of the variable descriptions and their current settings.
5432 confirm on/off: Enables warning questions for operations that are
5433 hard to recover from, e.g. rerunning the program while
5434 it is already running. Default is ON.
5436 editing on/off: Enables EMACS style command line editing
5437 of input. Previous lines can be recalled with
5438 control-P, the current line can be edited with control-B,
5439 you can search for commands with control-R, etc.
5442 history filename NAME: NAME is where the gdb command history
5443 will be stored. The default is .gdb_history,
5444 or the value of the environment variable
5447 history size N: The size, in commands, of the command history. The
5448 default is 256, or the value of the environment variable
5451 history save on/off: If this value is set to ON, the history file will
5452 be saved after exiting gdb. If set to OFF, the
5453 file will not be saved. The default is OFF.
5455 history expansion on/off: If this value is set to ON, then csh-like
5456 history expansion will be performed on
5457 command line input. The default is OFF.
5459 radix N: Sets the default radix for input and output. It can be set
5460 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5461 in the current radix, so "set radix 10" is always a no-op.
5463 height N: This integer value is the number of lines on a page. Default
5464 is 24, the current `stty rows'' setting, or the ``li#''
5465 setting from the termcap entry matching the environment
5468 width N: This integer value is the number of characters on a line.
5469 Default is 80, the current `stty cols'' setting, or the ``co#''
5470 setting from the termcap entry matching the environment
5473 Note: ``set screensize'' is obsolete. Use ``set height'' and
5474 ``set width'' instead.
5476 print address on/off: Print memory addresses in various command displays,
5477 such as stack traces and structure values. Gdb looks
5478 more ``symbolic'' if you turn this off; it looks more
5479 ``machine level'' with it on. Default is ON.
5481 print array on/off: Prettyprint arrays. New convenient format! Default
5484 print demangle on/off: Print C++ symbols in "source" form if on,
5487 print asm-demangle on/off: Same, for assembler level printouts
5490 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5493 * Support for Epoch Environment.
5495 The epoch environment is a version of Emacs v18 with windowing. One
5496 new command, ``inspect'', is identical to ``print'', except that if you
5497 are running in the epoch environment, the value is printed in its own
5501 * Support for Shared Libraries
5503 GDB can now debug programs and core files that use SunOS shared libraries.
5504 Symbols from a shared library cannot be referenced
5505 before the shared library has been linked with the program (this
5506 happens after you type ``run'' and before the function main() is entered).
5507 At any time after this linking (including when examining core files
5508 from dynamically linked programs), gdb reads the symbols from each
5509 shared library when you type the ``sharedlibrary'' command.
5510 It can be abbreviated ``share''.
5512 sharedlibrary REGEXP: Load shared object library symbols for files
5513 matching a unix regular expression. No argument
5514 indicates to load symbols for all shared libraries.
5516 info sharedlibrary: Status of loaded shared libraries.
5521 A watchpoint stops execution of a program whenever the value of an
5522 expression changes. Checking for this slows down execution
5523 tremendously whenever you are in the scope of the expression, but is
5524 quite useful for catching tough ``bit-spreader'' or pointer misuse
5525 problems. Some machines such as the 386 have hardware for doing this
5526 more quickly, and future versions of gdb will use this hardware.
5528 watch EXP: Set a watchpoint (breakpoint) for an expression.
5530 info watchpoints: Information about your watchpoints.
5532 delete N: Deletes watchpoint number N (same as breakpoints).
5533 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5534 enable N: Re-enables watchpoint number N (same as breakpoints).
5537 * C++ multiple inheritance
5539 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5542 * C++ exception handling
5544 Gdb now supports limited C++ exception handling. Besides the existing
5545 ability to breakpoint on an exception handler, gdb can breakpoint on
5546 the raising of an exception (before the stack is peeled back to the
5549 catch FOO: If there is a FOO exception handler in the dynamic scope,
5550 set a breakpoint to catch exceptions which may be raised there.
5551 Multiple exceptions (``catch foo bar baz'') may be caught.
5553 info catch: Lists all exceptions which may be caught in the
5554 current stack frame.
5557 * Minor command changes
5559 The command ``call func (arg, arg, ...)'' now acts like the print
5560 command, except it does not print or save a value if the function's result
5561 is void. This is similar to dbx usage.
5563 The ``up'' and ``down'' commands now always print the frame they end up
5564 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5565 frames without printing.
5567 * New directory command
5569 'dir' now adds directories to the FRONT of the source search path.
5570 The path starts off empty. Source files that contain debug information
5571 about the directory in which they were compiled can be found even
5572 with an empty path; Sun CC and GCC include this information. If GDB can't
5573 find your source file in the current directory, type "dir .".
5575 * Configuring GDB for compilation
5577 For normal use, type ``./configure host''. See README or gdb.texinfo
5580 GDB now handles cross debugging. If you are remotely debugging between
5581 two different machines, type ``./configure host -target=targ''.
5582 Host is the machine where GDB will run; targ is the machine
5583 where the program that you are debugging will run.
5585 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.