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*".
37 ** Frame filters and frame decorators have been added.
38 ** Temporary breakpoints are now supported.
42 Nios II ELF nios2*-*-elf
43 Nios II GNU/Linux nios2*-*-linux
44 Texas Instruments MSP430 msp430*-*-elf
46 * Removed native configurations
48 Support for these a.out NetBSD and OpenBSD obsolete configurations has
49 been removed. ELF variants of these configurations are kept supported.
51 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
52 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
53 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
54 i[34567]86-*-openbsd3.[0-3]
55 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
56 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
57 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
61 Like "catch throw", but catches a re-thrown exception.
63 Renamed from old "maint check-symtabs".
65 Perform consistency checks on symtabs.
67 Expand symtabs matching an optional regexp.
70 Display the details of GDB configure-time options.
72 maint set|show per-command
73 maint set|show per-command space
74 maint set|show per-command time
75 maint set|show per-command symtab
76 Enable display of per-command gdb resource usage.
78 remove-symbol-file FILENAME
79 remove-symbol-file -a ADDRESS
80 Remove a symbol file added via add-symbol-file. The file to remove
81 can be identified by its filename or by an address that lies within
82 the boundaries of this symbol file in memory.
86 set debug symfile off|on
88 Control display of debugging info regarding reading symbol files and
89 symbol tables within those files
91 set print raw frame-arguments
92 show print raw frame-arguments
93 Set/show whether to print frame arguments in raw mode,
94 disregarding any defined pretty-printers.
96 set remote trace-status-packet
97 show remote trace-status-packet
98 Set/show the use of remote protocol qTStatus packet.
102 Control display of debugging messages related to Nios II targets.
106 Control whether target-assisted range stepping is enabled.
108 set startup-with-shell
109 show startup-with-shell
110 Specifies whether Unix child processes are started via a shell or
113 * You can now use a literal value 'unlimited' for options that
114 interpret 0 or -1 as meaning "unlimited". E.g., "set
115 trace-buffer-size unlimited" is now an alias for "set
116 trace-buffer-size -1" and "set height unlimited" is now an alias for
119 * The "set debug symtab-create" debugging option of GDB has been changed to
120 accept a verbosity level. 0 means "off", 1 provides basic debugging
121 output, and values of 2 or greater provides more verbose output.
123 * New command-line options
125 Display the details of GDB configure-time options.
127 * The command 'tsave' can now support new option '-ctf' to save trace
128 buffer in Common Trace Format.
130 * Newly installed $prefix/bin/gcore acts as a shell interface for the
133 * GDB now implements the the C++ 'typeid' operator.
135 * The new convenience variable $_exception holds the exception being
136 thrown or caught at an exception-related catchpoint.
138 * The exception-related catchpoints, like "catch throw", now accept a
139 regular expression which can be used to filter exceptions by type.
141 * The new convenience variable $_exitsignal is automatically set to
142 the terminating signal number when the program being debugged dies
143 due to an uncaught signal.
147 ** The -trace-save MI command can optionally save trace buffer in Common
150 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
152 ** The command -data-list-register-values now accepts an optional
153 "--skip-unavailable" option. When used, only the available registers
156 ** The new command -trace-frame-collected dumps collected variables,
157 computed expressions, tvars, memory and registers in a traceframe.
159 ** The commands -stack-list-locals, -stack-list-arguments and
160 -stack-list-variables now accept an option "--skip-unavailable".
161 When used, only the available locals or arguments are displayed.
163 ** The -exec-run command now accepts an optional "--start" option.
164 When used, the command follows the same semantics as the "start"
165 command, stopping the program's execution at the start of its
168 ** The new commands -catch-assert and -catch-exceptions insert
169 catchpoints stopping the program when Ada exceptions are raised.
171 * New system-wide configuration scripts
172 A GDB installation now provides scripts suitable for use as system-wide
173 configuration scripts for the following systems:
177 * GDB now supports target-assigned range stepping with remote targets.
178 This improves the performance of stepping source lines by reducing
179 the number of control packets from/to GDB. See "New remote packets"
182 * GDB now understands the element 'tvar' in the XML traceframe info.
183 It has the id of the collected trace state variables.
185 * On S/390 targets that provide the transactional-execution feature,
186 the program interruption transaction diagnostic block (TDB) is now
187 represented as a number of additional "registers" in GDB.
193 The vCont packet supports a new 'r' action, that tells the remote
194 stub to step through an address range itself, without GDB
195 involvemement at each single-step.
197 qXfer:libraries-svr4:read's annex
198 The previously unused annex of the qXfer:libraries-svr4:read packet
199 is now used to support passing an argument list. The remote stub
200 reports support for this argument list to GDB's qSupported query.
201 The defined arguments are "start" and "prev", used to reduce work
202 necessary for library list updating, resulting in significant
205 * New features in the GDB remote stub, GDBserver
207 ** GDBserver now supports target-assisted range stepping. Currently
208 enabled on x86/x86_64 GNU/Linux targets.
210 ** GDBserver now adds element 'tvar' in the XML in the reply to
211 'qXfer:traceframe-info:read'. It has the id of the collected
212 trace state variables.
214 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
217 * New 'z' formatter for printing and examining memory, this displays the
218 value as hexadecimal zero padded on the left to the size of the type.
220 * GDB can now use Windows x64 unwinding data.
222 * The "set remotebaud" command has been replaced by "set serial baud".
223 Similarly, "show remotebaud" has been replaced by "show serial baud".
224 The "set remotebaud" and "show remotebaud" commands are still available
225 to provide backward compatibility with older versions of GDB.
227 *** Changes in GDB 7.6
229 * Target record has been renamed to record-full.
230 Record/replay is now enabled with the "record full" command.
231 This also affects settings that are associated with full record/replay
232 that have been moved from "set/show record" to "set/show record full":
234 set|show record full insn-number-max
235 set|show record full stop-at-limit
236 set|show record full memory-query
238 * A new record target "record-btrace" has been added. The new target
239 uses hardware support to record the control-flow of a process. It
240 does not support replaying the execution, but it implements the
241 below new commands for investigating the recorded execution log.
242 This new recording method can be enabled using:
246 The "record-btrace" target is only available on Intel Atom processors
247 and requires a Linux kernel 2.6.32 or later.
249 * Two new commands have been added for record/replay to give information
250 about the recorded execution without having to replay the execution.
251 The commands are only supported by "record btrace".
253 record instruction-history prints the execution history at
254 instruction granularity
256 record function-call-history prints the execution history at
259 * New native configurations
261 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
262 FreeBSD/powerpc powerpc*-*-freebsd
263 x86_64/Cygwin x86_64-*-cygwin*
264 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
268 ARM AArch64 aarch64*-*-elf
269 ARM AArch64 GNU/Linux aarch64*-*-linux
270 Lynx 178 PowerPC powerpc-*-lynx*178
271 x86_64/Cygwin x86_64-*-cygwin*
272 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
274 * If the configured location of system.gdbinit file (as given by the
275 --with-system-gdbinit option at configure time) is in the
276 data-directory (as specified by --with-gdb-datadir at configure
277 time) or in one of its subdirectories, then GDB will look for the
278 system-wide init file in the directory specified by the
279 --data-directory command-line option.
281 * New command line options:
283 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
284 other initialization files, unlike -nx which disables all of them.
286 * Removed command line options
288 -epoch This was used by the gdb mode in Epoch, an ancient fork of
291 * The 'ptype' and 'whatis' commands now accept an argument to control
294 * 'info proc' now works on some core files.
298 ** Vectors can be created with gdb.Type.vector.
300 ** Python's atexit.register now works in GDB.
302 ** Types can be pretty-printed via a Python API.
304 ** Python 3 is now supported (in addition to Python 2.4 or later)
306 ** New class gdb.Architecture exposes GDB's internal representation
307 of architecture in the Python API.
309 ** New method Frame.architecture returns the gdb.Architecture object
310 corresponding to the frame's architecture.
312 * New Python-based convenience functions:
314 ** $_memeq(buf1, buf2, length)
315 ** $_streq(str1, str2)
317 ** $_regex(str, regex)
319 * The 'cd' command now defaults to using '~' (the home directory) if not
322 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
323 default for GCC since November 2000.
325 * The command 'forward-search' can now be abbreviated as 'fo'.
327 * The command 'info tracepoints' can now display 'installed on target'
328 or 'not installed on target' for each non-pending location of tracepoint.
330 * New configure options
332 --enable-libmcheck/--disable-libmcheck
333 By default, development versions are built with -lmcheck on hosts
334 that support it, in order to help track memory corruption issues.
335 Release versions, on the other hand, are built without -lmcheck
336 by default. The --enable-libmcheck/--disable-libmcheck configure
337 options allow the user to override that default.
338 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
339 This configure option allows the user to build GDB with
340 libbabeltrace using which GDB can read Common Trace Format data.
342 * New commands (for set/show, see "New options" below)
345 Catch signals. This is similar to "handle", but allows commands and
346 conditions to be attached.
349 List the BFDs known to GDB.
351 python-interactive [command]
353 Start a Python interactive prompt, or evaluate the optional command
354 and print the result of expressions.
357 "py" is a new alias for "python".
359 enable type-printer [name]...
360 disable type-printer [name]...
361 Enable or disable type printers.
365 ** For the Renesas Super-H architecture, the "regs" command has been removed
366 (has been deprecated in GDB 7.5), and "info all-registers" should be used
371 set print type methods (on|off)
372 show print type methods
373 Control whether method declarations are displayed by "ptype".
374 The default is to show them.
376 set print type typedefs (on|off)
377 show print type typedefs
378 Control whether typedef definitions are displayed by "ptype".
379 The default is to show them.
381 set filename-display basename|relative|absolute
382 show filename-display
383 Control the way in which filenames is displayed.
384 The default is "relative", which preserves previous behavior.
386 set trace-buffer-size
387 show trace-buffer-size
388 Request target to change the size of trace buffer.
390 set remote trace-buffer-size-packet auto|on|off
391 show remote trace-buffer-size-packet
392 Control the use of the remote protocol `QTBuffer:size' packet.
396 Control display of debugging messages related to ARM AArch64.
399 set debug coff-pe-read
400 show debug coff-pe-read
401 Control display of debugging messages related to reading of COFF/PE
406 Control display of debugging messages related to Mach-O symbols
409 set debug notification
410 show debug notification
411 Control display of debugging info for async remote notification.
415 ** Command parameter changes are now notified using new async record
416 "=cmd-param-changed".
417 ** Trace frame changes caused by command "tfind" are now notified using
418 new async record "=traceframe-changed".
419 ** The creation, deletion and modification of trace state variables
420 are now notified using new async records "=tsv-created",
421 "=tsv-deleted" and "=tsv-modified".
422 ** The start and stop of process record are now notified using new
423 async record "=record-started" and "=record-stopped".
424 ** Memory changes are now notified using new async record
426 ** The data-disassemble command response will include a "fullname" field
427 containing the absolute file name when source has been requested.
428 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
429 command, to allow pattern filling of memory areas.
430 ** New commands "-catch-load"/"-catch-unload" added for intercepting
431 library load/unload events.
432 ** The response to breakpoint commands and breakpoint async records
433 includes an "installed" field containing a boolean state about each
434 non-pending tracepoint location is whether installed on target or not.
435 ** Output of the "-trace-status" command includes a "trace-file" field
436 containing the name of the trace file being examined. This field is
437 optional, and only present when examining a trace file.
438 ** The "fullname" field is now always present along with the "file" field,
439 even if the file cannot be found by GDB.
441 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
442 You must have the LZMA library available when configuring GDB for this
443 feature to be enabled. For more information, see:
444 http://fedoraproject.org/wiki/Features/MiniDebugInfo
449 Set the size of trace buffer. The remote stub reports support for this
450 packet to gdb's qSupported query.
453 Enable Branch Trace Store (BTS)-based branch tracing for the current
454 thread. The remote stub reports support for this packet to gdb's
458 Disable branch tracing for the current thread. The remote stub reports
459 support for this packet to gdb's qSupported query.
462 Read the traced branches for the current thread. The remote stub
463 reports support for this packet to gdb's qSupported query.
465 *** Changes in GDB 7.5
467 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
468 for more x32 ABI info.
470 * GDB now supports access to MIPS DSP registers on Linux targets.
472 * GDB now supports debugging microMIPS binaries.
474 * The "info os" command on GNU/Linux can now display information on
475 several new classes of objects managed by the operating system:
476 "info os procgroups" lists process groups
477 "info os files" lists file descriptors
478 "info os sockets" lists internet-domain sockets
479 "info os shm" lists shared-memory regions
480 "info os semaphores" lists semaphores
481 "info os msg" lists message queues
482 "info os modules" lists loaded kernel modules
484 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
485 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
486 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
487 options and inspect the probe arguments using the new $_probe_arg family
488 of convenience variables. You can obtain more information about SystemTap
489 in <http://sourceware.org/systemtap/>.
491 * GDB now supports reversible debugging on ARM, it allows you to
492 debug basic ARM and THUMB instructions, and provides
493 record/replay support.
495 * The option "symbol-reloading" has been deleted as it is no longer used.
499 ** GDB commands implemented in Python can now be put in command class
502 ** The "maint set python print-stack on|off" is now deleted.
504 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
505 apply "flag enum"-style pretty-printing to any enum.
507 ** gdb.lookup_symbol can now work when there is no current frame.
509 ** gdb.Symbol now has a 'line' attribute, holding the line number in
510 the source at which the symbol was defined.
512 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
513 method 'value'. The former indicates whether the symbol needs a
514 frame in order to compute its value, and the latter computes the
517 ** A new method 'referenced_value' on gdb.Value objects which can
518 dereference pointer as well as C++ reference values.
520 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
521 which return the global and static blocks (as gdb.Block objects),
522 of the underlying symbol table, respectively.
524 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
525 object associated with a PC value.
527 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
528 of the address range occupied by code for the current source line.
530 * Go language support.
531 GDB now supports debugging programs written in the Go programming
534 * GDBserver now supports stdio connections.
535 E.g. (gdb) target remote | ssh myhost gdbserver - hello
537 * The binary "gdbtui" can no longer be built or installed.
538 Use "gdb -tui" instead.
540 * GDB will now print "flag" enums specially. A flag enum is one where
541 all the enumerator values have no bits in common when pairwise
542 "and"ed. When printing a value whose type is a flag enum, GDB will
543 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
544 (gdb) print (enum E) 3
547 * The filename part of a linespec will now match trailing components
548 of a source file name. For example, "break gcc/expr.c:1000" will
549 now set a breakpoint in build/gcc/expr.c, but not
552 * The "info proc" and "generate-core-file" commands will now also
553 work on remote targets connected to GDBserver on Linux.
555 * The command "info catch" has been removed. It has been disabled
558 * The "catch exception" and "catch assert" commands now accept
559 a condition at the end of the command, much like the "break"
560 command does. For instance:
562 (gdb) catch exception Constraint_Error if Barrier = True
564 Previously, it was possible to add a condition to such catchpoints,
565 but it had to be done as a second step, after the catchpoint had been
566 created, using the "condition" command.
568 * The "info static-tracepoint-marker" command will now also work on
569 native Linux targets with in-process agent.
571 * GDB can now set breakpoints on inlined functions.
573 * The .gdb_index section has been updated to include symbols for
574 inlined functions. GDB will ignore older .gdb_index sections by
575 default, which could cause symbol files to be loaded more slowly
576 until their .gdb_index sections can be recreated. The new command
577 "set use-deprecated-index-sections on" will cause GDB to use any older
578 .gdb_index sections it finds. This will restore performance, but the
579 ability to set breakpoints on inlined functions will be lost in symbol
580 files with older .gdb_index sections.
582 The .gdb_index section has also been updated to record more information
583 about each symbol. This speeds up the "info variables", "info functions"
584 and "info types" commands when used with programs having the .gdb_index
585 section, as well as speeding up debugging with shared libraries using
586 the .gdb_index section.
588 * Ada support for GDB/MI Variable Objects has been added.
590 * GDB can now support 'breakpoint always-inserted mode' in 'record'
595 ** New command -info-os is the MI equivalent of "info os".
597 ** Output logs ("set logging" and related) now include MI output.
601 ** "set use-deprecated-index-sections on|off"
602 "show use-deprecated-index-sections on|off"
603 Controls the use of deprecated .gdb_index sections.
605 ** "catch load" and "catch unload" can be used to stop when a shared
606 library is loaded or unloaded, respectively.
608 ** "enable count" can be used to auto-disable a breakpoint after
611 ** "info vtbl" can be used to show the virtual method tables for
612 C++ and Java objects.
614 ** "explore" and its sub commands "explore value" and "explore type"
615 can be used to reccursively explore values and types of
616 expressions. These commands are available only if GDB is
617 configured with '--with-python'.
619 ** "info auto-load" shows status of all kinds of auto-loaded files,
620 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
621 sequences of commands files, "info auto-load python-scripts"
622 shows status of auto-loading Python script files,
623 "info auto-load local-gdbinit" shows status of loading init file
624 (.gdbinit) from current directory and "info auto-load libthread-db" shows
625 status of inferior specific thread debugging shared library loading.
627 ** "info auto-load-scripts", "set auto-load-scripts on|off"
628 and "show auto-load-scripts" commands have been deprecated, use their
629 "info auto-load python-scripts", "set auto-load python-scripts on|off"
630 and "show auto-load python-scripts" counterparts instead.
632 ** "dprintf location,format,args..." creates a dynamic printf, which
633 is basically a breakpoint that does a printf and immediately
634 resumes your program's execution, so it is like a printf that you
635 can insert dynamically at runtime instead of at compiletime.
637 ** "set print symbol"
639 Controls whether GDB attempts to display the symbol, if any,
640 corresponding to addresses it prints. This defaults to "on", but
641 you can set it to "off" to restore GDB's previous behavior.
643 * Deprecated commands
645 ** For the Renesas Super-H architecture, the "regs" command has been
646 deprecated, and "info all-registers" should be used instead.
650 Renesas RL78 rl78-*-elf
651 HP OpenVMS ia64 ia64-hp-openvms*
653 * GDBserver supports evaluation of breakpoint conditions. When
654 support is advertised by GDBserver, GDB may be told to send the
655 breakpoint conditions in bytecode form to GDBserver. GDBserver
656 will only report the breakpoint trigger to GDB when its condition
662 show mips compression
663 Select the compressed ISA encoding used in functions that have no symbol
664 information available. The encoding can be set to either of:
667 and is updated automatically from ELF file flags if available.
669 set breakpoint condition-evaluation
670 show breakpoint condition-evaluation
671 Control whether breakpoint conditions are evaluated by GDB ("host") or by
672 GDBserver ("target"). Default option "auto" chooses the most efficient
674 This option can improve debugger efficiency depending on the speed of the
678 Disable auto-loading globally.
681 Show auto-loading setting of all kinds of auto-loaded files.
683 set auto-load gdb-scripts on|off
684 show auto-load gdb-scripts
685 Control auto-loading of GDB canned sequences of commands files.
687 set auto-load python-scripts on|off
688 show auto-load python-scripts
689 Control auto-loading of Python script files.
691 set auto-load local-gdbinit on|off
692 show auto-load local-gdbinit
693 Control loading of init file (.gdbinit) from current directory.
695 set auto-load libthread-db on|off
696 show auto-load libthread-db
697 Control auto-loading of inferior specific thread debugging shared library.
699 set auto-load scripts-directory <dir1>[:<dir2>...]
700 show auto-load scripts-directory
701 Set a list of directories from which to load auto-loaded scripts.
702 Automatically loaded Python scripts and GDB scripts are located in one
703 of the directories listed by this option.
704 The delimiter (':' above) may differ according to the host platform.
706 set auto-load safe-path <dir1>[:<dir2>...]
707 show auto-load safe-path
708 Set a list of directories from which it is safe to auto-load files.
709 The delimiter (':' above) may differ according to the host platform.
711 set debug auto-load on|off
713 Control display of debugging info for auto-loading the files above.
715 set dprintf-style gdb|call|agent
717 Control the way in which a dynamic printf is performed; "gdb"
718 requests a GDB printf command, while "call" causes dprintf to call a
719 function in the inferior. "agent" requests that the target agent
720 (such as GDBserver) do the printing.
722 set dprintf-function <expr>
723 show dprintf-function
724 set dprintf-channel <expr>
726 Set the function and optional first argument to the call when using
727 the "call" style of dynamic printf.
729 set disconnected-dprintf on|off
730 show disconnected-dprintf
731 Control whether agent-style dynamic printfs continue to be in effect
732 after GDB disconnects.
734 * New configure options
737 Configure default value for the 'set auto-load scripts-directory'
738 setting above. It defaults to '$debugdir:$datadir/auto-load',
739 $debugdir representing global debugging info directories (available
740 via 'show debug-file-directory') and $datadir representing GDB's data
741 directory (available via 'show data-directory').
743 --with-auto-load-safe-path
744 Configure default value for the 'set auto-load safe-path' setting
745 above. It defaults to the --with-auto-load-dir setting.
747 --without-auto-load-safe-path
748 Set 'set auto-load safe-path' to '/', effectively disabling this
753 z0/z1 conditional breakpoints extension
755 The z0/z1 breakpoint insertion packets have been extended to carry
756 a list of conditional expressions over to the remote stub depending on the
757 condition evaluation mode. The use of this extension can be controlled
758 via the "set remote conditional-breakpoints-packet" command.
762 Specify the signals which the remote stub may pass to the debugged
763 program without GDB involvement.
765 * New command line options
767 --init-command=FILE, -ix Like --command, -x but execute it
768 before loading inferior.
769 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
770 execute it before loading inferior.
772 *** Changes in GDB 7.4
774 * GDB now handles ambiguous linespecs more consistently; the existing
775 FILE:LINE support has been expanded to other types of linespecs. A
776 breakpoint will now be set on all matching locations in all
777 inferiors, and locations will be added or removed according to
780 * GDB now allows you to skip uninteresting functions and files when
781 stepping with the "skip function" and "skip file" commands.
783 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
784 and "show remote hardware-watchpoint-length-limit". These allows to
785 set or show the maximum length limit (in bytes) of a remote
786 target hardware watchpoint.
788 This allows e.g. to use "unlimited" hardware watchpoints with the
789 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
790 watchpoints are slower than real hardware watchpoints but are
791 significantly faster than gdb software watchpoints.
795 ** The register_pretty_printer function in module gdb.printing now takes
796 an optional `replace' argument. If True, the new printer replaces any
799 ** The "maint set python print-stack on|off" command has been
800 deprecated and will be deleted in GDB 7.5.
801 A new command: "set python print-stack none|full|message" has
802 replaced it. Additionally, the default for "print-stack" is
803 now "message", which just prints the error message without
806 ** A prompt substitution hook (prompt_hook) is now available to the
809 ** A new Python module, gdb.prompt has been added to the GDB Python
810 modules library. This module provides functionality for
811 escape sequences in prompts (used by set/show
812 extended-prompt). These escape sequences are replaced by their
815 ** Python commands and convenience-functions located in
816 'data-directory'/python/gdb/command and
817 'data-directory'/python/gdb/function are now automatically loaded
820 ** Blocks now provide four new attributes. global_block and
821 static_block will return the global and static blocks
822 respectively. is_static and is_global are boolean attributes
823 that indicate if the block is one of those two types.
825 ** Symbols now provide the "type" attribute, the type of the symbol.
827 ** The "gdb.breakpoint" function has been deprecated in favor of
830 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
831 of a function. This class is based on the "finish" command
832 available in the CLI.
834 ** Type objects for struct and union types now allow access to
835 the fields using standard Python dictionary (mapping) methods.
836 For example, "some_type['myfield']" now works, as does
839 ** A new event "gdb.new_objfile" has been added, triggered by loading a
842 ** A new function, "deep_items" has been added to the gdb.types
843 module in the GDB Python modules library. This function returns
844 an iterator over the fields of a struct or union type. Unlike
845 the standard Python "iteritems" method, it will recursively traverse
846 any anonymous fields.
850 ** "*stopped" events can report several new "reason"s, such as
853 ** Breakpoint changes are now notified using new async records, like
854 "=breakpoint-modified".
856 ** New command -ada-task-info.
858 * libthread-db-search-path now supports two special values: $sdir and $pdir.
859 $sdir specifies the default system locations of shared libraries.
860 $pdir specifies the directory where the libpthread used by the application
863 GDB no longer looks in $sdir and $pdir after it has searched the directories
864 mentioned in libthread-db-search-path. If you want to search those
865 directories, they must be specified in libthread-db-search-path.
866 The default value of libthread-db-search-path on GNU/Linux and Solaris
867 systems is now "$sdir:$pdir".
869 $pdir is not supported by gdbserver, it is currently ignored.
870 $sdir is supported by gdbserver.
872 * New configure option --with-iconv-bin.
873 When using the internationalization support like the one in the GNU C
874 library, GDB will invoke the "iconv" program to get a list of supported
875 character sets. If this program lives in a non-standard location, one can
876 use this option to specify where to find it.
878 * When natively debugging programs on PowerPC BookE processors running
879 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
880 watchpoints, which specify a mask in addition to an address to watch.
881 The mask specifies that some bits of an address (the bits which are
882 reset in the mask) should be ignored when matching the address accessed
883 by the inferior against the watchpoint address. See the "PowerPC Embedded"
884 section in the user manual for more details.
886 * The new option --once causes GDBserver to stop listening for connections once
887 the first connection is made. The listening port used by GDBserver will
888 become available after that.
890 * New commands "info macros" and "alias" have been added.
892 * New function parameters suffix @entry specifies value of function parameter
893 at the time the function got called. Entry values are available only since
899 "!" is now an alias of the "shell" command.
900 Note that no space is needed between "!" and SHELL COMMAND.
904 watch EXPRESSION mask MASK_VALUE
905 The watch command now supports the mask argument which allows creation
906 of masked watchpoints, if the current architecture supports this feature.
908 info auto-load-scripts [REGEXP]
909 This command was formerly named "maintenance print section-scripts".
910 It is now generally useful and is no longer a maintenance-only command.
912 info macro [-all] [--] MACRO
913 The info macro command has new options `-all' and `--'. The first for
914 printing all definitions of a macro. The second for explicitly specifying
915 the end of arguments and the beginning of the macro name in case the macro
916 name starts with a hyphen.
918 collect[/s] EXPRESSIONS
919 The tracepoint collect command now takes an optional modifier "/s"
920 that directs it to dereference pointer-to-character types and
921 collect the bytes of memory up to a zero byte. The behavior is
922 similar to what you see when you use the regular print command on a
923 string. An optional integer following the "/s" sets a bound on the
924 number of bytes that will be collected.
927 The trace start command now interprets any supplied arguments as a
928 note to be recorded with the trace run, with an effect similar to
929 setting the variable trace-notes.
932 The trace stop command now interprets any arguments as a note to be
933 mentioned along with the tstatus report that the trace was stopped
934 with a command. The effect is similar to setting the variable
937 * Tracepoints can now be enabled and disabled at any time after a trace
938 experiment has been started using the standard "enable" and "disable"
939 commands. It is now possible to start a trace experiment with no enabled
940 tracepoints; GDB will display a warning, but will allow the experiment to
941 begin, assuming that tracepoints will be enabled as needed while the trace
944 * Fast tracepoints on 32-bit x86-architectures can now be placed at
945 locations with 4-byte instructions, when they were previously
946 limited to locations with instructions of 5 bytes or longer.
950 set debug dwarf2-read
951 show debug dwarf2-read
952 Turns on or off display of debugging messages related to reading
953 DWARF debug info. The default is off.
955 set debug symtab-create
956 show debug symtab-create
957 Turns on or off display of debugging messages related to symbol table
958 creation. The default is off.
962 Set the GDB prompt, and allow escape sequences to be inserted to
963 display miscellaneous information (see 'help set extended-prompt'
964 for the list of sequences). This prompt (and any information
965 accessed through the escape sequences) is updated every time the
968 set print entry-values (both|compact|default|if-needed|no|only|preferred)
969 show print entry-values
970 Set printing of frame argument values at function entry. In some cases
971 GDB can determine the value of function argument which was passed by the
972 function caller, even if the value was modified inside the called function.
974 set debug entry-values
975 show debug entry-values
976 Control display of debugging info for determining frame argument values at
977 function entry and virtual tail call frames.
979 set basenames-may-differ
980 show basenames-may-differ
981 Set whether a source file may have multiple base names.
982 (A "base name" is the name of a file with the directory part removed.
983 Example: The base name of "/home/user/hello.c" is "hello.c".)
984 If set, GDB will canonicalize file names (e.g., expand symlinks)
985 before comparing them. Canonicalization is an expensive operation,
986 but it allows the same file be known by more than one base name.
987 If not set (the default), all source files are assumed to have just
988 one base name, and gdb will do file name comparisons more efficiently.
994 Set a user name and notes for the current and any future trace runs.
995 This is useful for long-running and/or disconnected traces, to
996 inform others (or yourself) as to who is running the trace, supply
997 contact information, or otherwise explain what is going on.
1000 show trace-stop-notes
1001 Set a note attached to the trace run, that is displayed when the
1002 trace has been stopped by a tstop command. This is useful for
1003 instance as an explanation, if you are stopping a trace run that was
1004 started by someone else.
1006 * New remote packets
1010 Dynamically enable a tracepoint in a started trace experiment.
1014 Dynamically disable a tracepoint in a started trace experiment.
1018 Set the user and notes of the trace run.
1022 Query the current status of a tracepoint.
1026 Query the minimum length of instruction at which a fast tracepoint may
1029 * Dcache size (number of lines) and line-size are now runtime-configurable
1030 via "set dcache line" and "set dcache line-size" commands.
1034 Texas Instruments TMS320C6x tic6x-*-*
1038 Renesas RL78 rl78-*-elf
1040 *** Changes in GDB 7.3.1
1042 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1044 *** Changes in GDB 7.3
1046 * GDB has a new command: "thread find [REGEXP]".
1047 It finds the thread id whose name, target id, or thread extra info
1048 matches the given regular expression.
1050 * The "catch syscall" command now works on mips*-linux* targets.
1052 * The -data-disassemble MI command now supports modes 2 and 3 for
1053 dumping the instruction opcodes.
1055 * New command line options
1057 -data-directory DIR Specify DIR as the "data-directory".
1058 This is mostly for testing purposes.
1060 * The "maint set python auto-load on|off" command has been renamed to
1061 "set auto-load-scripts on|off".
1063 * GDB has a new command: "set directories".
1064 It is like the "dir" command except that it replaces the
1065 source path list instead of augmenting it.
1067 * GDB now understands thread names.
1069 On GNU/Linux, "info threads" will display the thread name as set by
1070 prctl or pthread_setname_np.
1072 There is also a new command, "thread name", which can be used to
1073 assign a name internally for GDB to display.
1076 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1077 has been integrated into GDB.
1081 ** The function gdb.Write now accepts an optional keyword 'stream'.
1082 This keyword, when provided, will direct the output to either
1083 stdout, stderr, or GDB's logging output.
1085 ** Parameters can now be be sub-classed in Python, and in particular
1086 you may implement the get_set_doc and get_show_doc functions.
1087 This improves how Parameter set/show documentation is processed
1088 and allows for more dynamic content.
1090 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1091 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1092 have an is_valid method.
1094 ** Breakpoints can now be sub-classed in Python, and in particular
1095 you may implement a 'stop' function that is executed each time
1096 the inferior reaches that breakpoint.
1098 ** New function gdb.lookup_global_symbol looks up a global symbol.
1100 ** GDB values in Python are now callable if the value represents a
1101 function. For example, if 'some_value' represents a function that
1102 takes two integer parameters and returns a value, you can call
1103 that function like so:
1105 result = some_value (10,20)
1107 ** Module gdb.types has been added.
1108 It contains a collection of utilities for working with gdb.Types objects:
1109 get_basic_type, has_field, make_enum_dict.
1111 ** Module gdb.printing has been added.
1112 It contains utilities for writing and registering pretty-printers.
1113 New classes: PrettyPrinter, SubPrettyPrinter,
1114 RegexpCollectionPrettyPrinter.
1115 New function: register_pretty_printer.
1117 ** New commands "info pretty-printers", "enable pretty-printer" and
1118 "disable pretty-printer" have been added.
1120 ** gdb.parameter("directories") is now available.
1122 ** New function gdb.newest_frame returns the newest frame in the
1125 ** The gdb.InferiorThread class has a new "name" attribute. This
1126 holds the thread's name.
1128 ** Python Support for Inferior events.
1129 Python scripts can add observers to be notified of events
1130 occurring in the process being debugged.
1131 The following events are currently supported:
1132 - gdb.events.cont Continue event.
1133 - gdb.events.exited Inferior exited event.
1134 - gdb.events.stop Signal received, and Breakpoint hit events.
1138 ** GDB now puts template parameters in scope when debugging in an
1139 instantiation. For example, if you have:
1141 template<int X> int func (void) { return X; }
1143 then if you step into func<5>, "print X" will show "5". This
1144 feature requires proper debuginfo support from the compiler; it
1145 was added to GCC 4.5.
1147 ** The motion commands "next", "finish", "until", and "advance" now
1148 work better when exceptions are thrown. In particular, GDB will
1149 no longer lose control of the inferior; instead, the GDB will
1150 stop the inferior at the point at which the exception is caught.
1151 This functionality requires a change in the exception handling
1152 code that was introduced in GCC 4.5.
1154 * GDB now follows GCC's rules on accessing volatile objects when
1155 reading or writing target state during expression evaluation.
1156 One notable difference to prior behavior is that "print x = 0"
1157 no longer generates a read of x; the value of the assignment is
1158 now always taken directly from the value being assigned.
1160 * GDB now has some support for using labels in the program's source in
1161 linespecs. For instance, you can use "advance label" to continue
1162 execution to a label.
1164 * GDB now has support for reading and writing a new .gdb_index
1165 section. This section holds a fast index of DWARF debugging
1166 information and can be used to greatly speed up GDB startup and
1167 operation. See the documentation for `save gdb-index' for details.
1169 * The "watch" command now accepts an optional "-location" argument.
1170 When used, this causes GDB to watch the memory referred to by the
1171 expression. Such a watchpoint is never deleted due to it going out
1174 * GDB now supports thread debugging of core dumps on GNU/Linux.
1176 GDB now activates thread debugging using the libthread_db library
1177 when debugging GNU/Linux core dumps, similarly to when debugging
1178 live processes. As a result, when debugging a core dump file, GDB
1179 is now able to display pthread_t ids of threads. For example, "info
1180 threads" shows the same output as when debugging the process when it
1181 was live. In earlier releases, you'd see something like this:
1184 * 1 LWP 6780 main () at main.c:10
1186 While now you see this:
1189 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1191 It is also now possible to inspect TLS variables when debugging core
1194 When debugging a core dump generated on a machine other than the one
1195 used to run GDB, you may need to point GDB at the correct
1196 libthread_db library with the "set libthread-db-search-path"
1197 command. See the user manual for more details on this command.
1199 * When natively debugging programs on PowerPC BookE processors running
1200 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1201 which stop execution of the inferior whenever it executes an instruction
1202 at any address within the specified range. See the "PowerPC Embedded"
1203 section in the user manual for more details.
1205 * New features in the GDB remote stub, GDBserver
1207 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1208 and i686 LynxOS (version 5.x).
1210 ** GDBserver is now supported on Blackfin Linux.
1212 * New native configurations
1214 ia64 HP-UX ia64-*-hpux*
1218 Analog Devices, Inc. Blackfin Processor bfin-*
1220 * Ada task switching is now supported on sparc-elf targets when
1221 debugging a program using the Ravenscar Profile. For more information,
1222 see the "Tasking Support when using the Ravenscar Profile" section
1223 in the GDB user manual.
1225 * Guile support was removed.
1227 * New features in the GNU simulator
1229 ** The --map-info flag lists all known core mappings.
1231 ** CFI flashes may be simulated via the "cfi" device.
1233 *** Changes in GDB 7.2
1235 * Shared library support for remote targets by default
1237 When GDB is configured for a generic, non-OS specific target, like
1238 for example, --target=arm-eabi or one of the many *-*-elf targets,
1239 GDB now queries remote stubs for loaded shared libraries using the
1240 `qXfer:libraries:read' packet. Previously, shared library support
1241 was always disabled for such configurations.
1245 ** Argument Dependent Lookup (ADL)
1247 In C++ ADL lookup directs function search to the namespaces of its
1248 arguments even if the namespace has not been imported.
1258 Here the compiler will search for `foo' in the namespace of 'b'
1259 and find A::foo. GDB now supports this. This construct is commonly
1260 used in the Standard Template Library for operators.
1262 ** Improved User Defined Operator Support
1264 In addition to member operators, GDB now supports lookup of operators
1265 defined in a namespace and imported with a `using' directive, operators
1266 defined in the global scope, operators imported implicitly from an
1267 anonymous namespace, and the ADL operators mentioned in the previous
1269 GDB now also supports proper overload resolution for all the previously
1270 mentioned flavors of operators.
1272 ** static const class members
1274 Printing of static const class members that are initialized in the
1275 class definition has been fixed.
1277 * Windows Thread Information Block access.
1279 On Windows targets, GDB now supports displaying the Windows Thread
1280 Information Block (TIB) structure. This structure is visible either
1281 by using the new command `info w32 thread-information-block' or, by
1282 dereferencing the new convenience variable named `$_tlb', a
1283 thread-specific pointer to the TIB. This feature is also supported
1284 when remote debugging using GDBserver.
1286 * Static tracepoints
1288 Static tracepoints are calls in the user program into a tracing
1289 library. One such library is a port of the LTTng kernel tracer to
1290 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1291 When debugging with GDBserver, GDB now supports combining the GDB
1292 tracepoint machinery with such libraries. For example: the user can
1293 use GDB to probe a static tracepoint marker (a call from the user
1294 program into the tracing library) with the new "strace" command (see
1295 "New commands" below). This creates a "static tracepoint" in the
1296 breakpoint list, that can be manipulated with the same feature set
1297 as fast and regular tracepoints. E.g., collect registers, local and
1298 global variables, collect trace state variables, and define
1299 tracepoint conditions. In addition, the user can collect extra
1300 static tracepoint marker specific data, by collecting the new
1301 $_sdata internal variable. When analyzing the trace buffer, you can
1302 inspect $_sdata like any other variable available to GDB. For more
1303 information, see the "Tracepoints" chapter in GDB user manual. New
1304 remote packets have been defined to support static tracepoints, see
1305 the "New remote packets" section below.
1307 * Better reconstruction of tracepoints after disconnected tracing
1309 GDB will attempt to download the original source form of tracepoint
1310 definitions when starting a trace run, and then will upload these
1311 upon reconnection to the target, resulting in a more accurate
1312 reconstruction of the tracepoints that are in use on the target.
1316 You can now exercise direct control over the ways that GDB can
1317 affect your program. For instance, you can disallow the setting of
1318 breakpoints, so that the program can run continuously (assuming
1319 non-stop mode). In addition, the "observer" variable is available
1320 to switch all of the different controls; in observer mode, GDB
1321 cannot affect the target's behavior at all, which is useful for
1322 tasks like diagnosing live systems in the field.
1324 * The new convenience variable $_thread holds the number of the
1327 * New remote packets
1331 Return the address of the Windows Thread Information Block of a given thread.
1335 In response to several of the tracepoint packets, the target may now
1336 also respond with a number of intermediate `qRelocInsn' request
1337 packets before the final result packet, to have GDB handle
1338 relocating an instruction to execute at a different address. This
1339 is particularly useful for stubs that support fast tracepoints. GDB
1340 reports support for this feature in the qSupported packet.
1344 List static tracepoint markers in the target program.
1348 List static tracepoint markers at a given address in the target
1351 qXfer:statictrace:read
1353 Read the static trace data collected (by a `collect $_sdata'
1354 tracepoint action). The remote stub reports support for this packet
1355 to gdb's qSupported query.
1359 Send the current settings of GDB's permission flags.
1363 Send part of the source (textual) form of a tracepoint definition,
1364 which includes location, conditional, and action list.
1366 * The source command now accepts a -s option to force searching for the
1367 script in the source search path even if the script name specifies
1370 * New features in the GDB remote stub, GDBserver
1372 - GDBserver now support tracepoints (including fast tracepoints, and
1373 static tracepoints). The feature is currently supported by the
1374 i386-linux and amd64-linux builds. See the "Tracepoints support
1375 in gdbserver" section in the manual for more information.
1377 GDBserver JIT compiles the tracepoint's conditional agent
1378 expression bytecode into native code whenever possible for low
1379 overhead dynamic tracepoints conditionals. For such tracepoints,
1380 an expression that examines program state is evaluated when the
1381 tracepoint is reached, in order to determine whether to capture
1382 trace data. If the condition is simple and false, processing the
1383 tracepoint finishes very quickly and no data is gathered.
1385 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1386 for static tracepoints support.
1388 - GDBserver now supports x86_64 Windows 64-bit debugging.
1390 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1391 it understands register description.
1393 * The --batch flag now disables pagination and queries.
1395 * X86 general purpose registers
1397 GDB now supports reading/writing byte, word and double-word x86
1398 general purpose registers directly. This means you can use, say,
1399 $ah or $ax to refer, respectively, to the byte register AH and
1400 16-bit word register AX that are actually portions of the 32-bit
1401 register EAX or 64-bit register RAX.
1403 * The `commands' command now accepts a range of breakpoints to modify.
1404 A plain `commands' following a command that creates multiple
1405 breakpoints affects all the breakpoints set by that command. This
1406 applies to breakpoints set by `rbreak', and also applies when a
1407 single `break' command creates multiple breakpoints (e.g.,
1408 breakpoints on overloaded c++ functions).
1410 * The `rbreak' command now accepts a filename specification as part of
1411 its argument, limiting the functions selected by the regex to those
1412 in the specified file.
1414 * Support for remote debugging Windows and SymbianOS shared libraries
1415 from Unix hosts has been improved. Non Windows GDB builds now can
1416 understand target reported file names that follow MS-DOS based file
1417 system semantics, such as file names that include drive letters and
1418 use the backslash character as directory separator. This makes it
1419 possible to transparently use the "set sysroot" and "set
1420 solib-search-path" on Unix hosts to point as host copies of the
1421 target's shared libraries. See the new command "set
1422 target-file-system-kind" described below, and the "Commands to
1423 specify files" section in the user manual for more information.
1427 eval template, expressions...
1428 Convert the values of one or more expressions under the control
1429 of the string template to a command line, and call it.
1431 set target-file-system-kind unix|dos-based|auto
1432 show target-file-system-kind
1433 Set or show the assumed file system kind for target reported file
1436 save breakpoints <filename>
1437 Save all current breakpoint definitions to a file suitable for use
1438 in a later debugging session. To read the saved breakpoint
1439 definitions, use the `source' command.
1441 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1444 info static-tracepoint-markers
1445 Display information about static tracepoint markers in the target.
1447 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1448 Define a static tracepoint by probing a marker at the given
1449 function, line, address, or marker ID.
1453 Enable and disable observer mode.
1455 set may-write-registers on|off
1456 set may-write-memory on|off
1457 set may-insert-breakpoints on|off
1458 set may-insert-tracepoints on|off
1459 set may-insert-fast-tracepoints on|off
1460 set may-interrupt on|off
1461 Set individual permissions for GDB effects on the target. Note that
1462 some of these settings can have undesirable or surprising
1463 consequences, particularly when changed in the middle of a session.
1464 For instance, disabling the writing of memory can prevent
1465 breakpoints from being inserted, cause single-stepping to fail, or
1466 even crash your program, if you disable after breakpoints have been
1467 inserted. However, GDB should not crash.
1469 set record memory-query on|off
1470 show record memory-query
1471 Control whether to stop the inferior if memory changes caused
1472 by an instruction cannot be recorded.
1477 The disassemble command now supports "start,+length" form of two arguments.
1481 ** GDB now provides a new directory location, called the python directory,
1482 where Python scripts written for GDB can be installed. The location
1483 of that directory is <data-directory>/python, where <data-directory>
1484 is the GDB data directory. For more details, see section `Scripting
1485 GDB using Python' in the manual.
1487 ** The GDB Python API now has access to breakpoints, symbols, symbol
1488 tables, program spaces, inferiors, threads and frame's code blocks.
1489 Additionally, GDB Parameters can now be created from the API, and
1490 manipulated via set/show in the CLI.
1492 ** New functions gdb.target_charset, gdb.target_wide_charset,
1493 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1495 ** New exception gdb.GdbError.
1497 ** Pretty-printers are now also looked up in the current program space.
1499 ** Pretty-printers can now be individually enabled and disabled.
1501 ** GDB now looks for names of Python scripts to auto-load in a
1502 special section named `.debug_gdb_scripts', in addition to looking
1503 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1505 * Tracepoint actions were unified with breakpoint commands. In particular,
1506 there are no longer differences in "info break" output for breakpoints and
1507 tracepoints and the "commands" command can be used for both tracepoints and
1508 regular breakpoints.
1512 ARM Symbian arm*-*-symbianelf*
1514 * D language support.
1515 GDB now supports debugging programs written in the D programming
1518 * GDB now supports the extended ptrace interface for PowerPC which is
1519 available since Linux kernel version 2.6.34. This automatically enables
1520 any hardware breakpoints and additional hardware watchpoints available in
1521 the processor. The old ptrace interface exposes just one hardware
1522 watchpoint and no hardware breakpoints.
1524 * GDB is now able to use the Data Value Compare (DVC) register available on
1525 embedded PowerPC processors to implement in hardware simple watchpoint
1526 conditions of the form:
1528 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1530 This works in native GDB running on Linux kernels with the extended ptrace
1531 interface mentioned above.
1533 *** Changes in GDB 7.1
1537 ** Namespace Support
1539 GDB now supports importing of namespaces in C++. This enables the
1540 user to inspect variables from imported namespaces. Support for
1541 namepace aliasing has also been added. So, if a namespace is
1542 aliased in the current scope (e.g. namepace C=A; ) the user can
1543 print variables using the alias (e.g. (gdb) print C::x).
1547 All known bugs relating to the printing of virtual base class were
1548 fixed. It is now possible to call overloaded static methods using a
1553 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1554 and reinterpret_cast<> are now handled by the C++ expression parser.
1558 Xilinx MicroBlaze microblaze-*-*
1563 Xilinx MicroBlaze microblaze
1566 * Multi-program debugging.
1568 GDB now has support for multi-program (a.k.a. multi-executable or
1569 multi-exec) debugging. This allows for debugging multiple inferiors
1570 simultaneously each running a different program under the same GDB
1571 session. See "Debugging Multiple Inferiors and Programs" in the
1572 manual for more information. This implied some user visible changes
1573 in the multi-inferior support. For example, "info inferiors" now
1574 lists inferiors that are not running yet or that have exited
1575 already. See also "New commands" and "New options" below.
1577 * New tracing features
1579 GDB's tracepoint facility now includes several new features:
1581 ** Trace state variables
1583 GDB tracepoints now include support for trace state variables, which
1584 are variables managed by the target agent during a tracing
1585 experiment. They are useful for tracepoints that trigger each
1586 other, so for instance one tracepoint can count hits in a variable,
1587 and then a second tracepoint has a condition that is true when the
1588 count reaches a particular value. Trace state variables share the
1589 $-syntax of GDB convenience variables, and can appear in both
1590 tracepoint actions and condition expressions. Use the "tvariable"
1591 command to create, and "info tvariables" to view; see "Trace State
1592 Variables" in the manual for more detail.
1596 GDB now includes an option for defining fast tracepoints, which
1597 targets may implement more efficiently, such as by installing a jump
1598 into the target agent rather than a trap instruction. The resulting
1599 speedup can be by two orders of magnitude or more, although the
1600 tradeoff is that some program locations on some target architectures
1601 might not allow fast tracepoint installation, for instance if the
1602 instruction to be replaced is shorter than the jump. To request a
1603 fast tracepoint, use the "ftrace" command, with syntax identical to
1604 the regular trace command.
1606 ** Disconnected tracing
1608 It is now possible to detach GDB from the target while it is running
1609 a trace experiment, then reconnect later to see how the experiment
1610 is going. In addition, a new variable disconnected-tracing lets you
1611 tell the target agent whether to continue running a trace if the
1612 connection is lost unexpectedly.
1616 GDB now has the ability to save the trace buffer into a file, and
1617 then use that file as a target, similarly to you can do with
1618 corefiles. You can select trace frames, print data that was
1619 collected in them, and use tstatus to display the state of the
1620 tracing run at the moment that it was saved. To create a trace
1621 file, use "tsave <filename>", and to use it, do "target tfile
1624 ** Circular trace buffer
1626 You can ask the target agent to handle the trace buffer as a
1627 circular buffer, discarding the oldest trace frames to make room for
1628 newer ones, by setting circular-trace-buffer to on. This feature may
1629 not be available for all target agents.
1634 The disassemble command, when invoked with two arguments, now requires
1635 the arguments to be comma-separated.
1638 The info variables command now displays variable definitions. Files
1639 which only declare a variable are not shown.
1642 The source command is now capable of sourcing Python scripts.
1643 This feature is dependent on the debugger being build with Python
1646 Related to this enhancement is also the introduction of a new command
1647 "set script-extension" (see below).
1649 * New commands (for set/show, see "New options" below)
1651 record save [<FILENAME>]
1652 Save a file (in core file format) containing the process record
1653 execution log for replay debugging at a later time.
1655 record restore <FILENAME>
1656 Restore the process record execution log that was saved at an
1657 earlier time, for replay debugging.
1659 add-inferior [-copies <N>] [-exec <FILENAME>]
1662 clone-inferior [-copies <N>] [ID]
1663 Make a new inferior ready to execute the same program another
1664 inferior has loaded.
1669 maint info program-spaces
1670 List the program spaces loaded into GDB.
1672 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1673 show remote interrupt-sequence
1674 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1675 as the sequence to the remote target in order to interrupt the execution.
1676 Ctrl-C is a default. Some system prefers BREAK which is high level of
1677 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1678 Magic SysRq g. It is BREAK signal and character 'g'.
1680 set remote interrupt-on-connect [on | off]
1681 show remote interrupt-on-connect
1682 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1683 remote target when gdb connects to it. This is needed when you debug
1686 set remotebreak [on | off]
1688 Deprecated. Use "set/show remote interrupt-sequence" instead.
1690 tvariable $NAME [ = EXP ]
1691 Create or modify a trace state variable.
1694 List trace state variables and their values.
1696 delete tvariable $NAME ...
1697 Delete one or more trace state variables.
1700 Evaluate the given expressions without collecting anything into the
1701 trace buffer. (Valid in tracepoint actions only.)
1703 ftrace FN / FILE:LINE / *ADDR
1704 Define a fast tracepoint at the given function, line, or address.
1706 * New expression syntax
1708 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1709 GDB now parses 0b101010 identically with 42.
1713 set follow-exec-mode new|same
1714 show follow-exec-mode
1715 Control whether GDB reuses the same inferior across an exec call or
1716 creates a new one. This is useful to be able to restart the old
1717 executable after the inferior having done an exec call.
1719 set default-collect EXPR, ...
1720 show default-collect
1721 Define a list of expressions to be collected at each tracepoint.
1722 This is a useful way to ensure essential items are not overlooked,
1723 such as registers or a critical global variable.
1725 set disconnected-tracing
1726 show disconnected-tracing
1727 If set to 1, the target is instructed to continue tracing if it
1728 loses its connection to GDB. If 0, the target is to stop tracing
1731 set circular-trace-buffer
1732 show circular-trace-buffer
1733 If set to on, the target is instructed to use a circular trace buffer
1734 and discard the oldest trace frames instead of stopping the trace due
1735 to a full trace buffer. If set to off, the trace stops when the buffer
1736 fills up. Some targets may not support this.
1738 set script-extension off|soft|strict
1739 show script-extension
1740 If set to "off", the debugger does not perform any script language
1741 recognition, and all sourced files are assumed to be GDB scripts.
1742 If set to "soft" (the default), files are sourced according to
1743 filename extension, falling back to GDB scripts if the first
1745 If set to "strict", files are sourced according to filename extension.
1747 set ada trust-PAD-over-XVS on|off
1748 show ada trust-PAD-over-XVS
1749 If off, activate a workaround against a bug in the debugging information
1750 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1751 the GCC sources for more information about the GNAT encoding and
1752 PAD types in particular). It is always safe to set this option to
1753 off, but this introduces a slight performance penalty. The default
1756 * Python API Improvements
1758 ** GDB provides the new class gdb.LazyString. This is useful in
1759 some pretty-printing cases. The new method gdb.Value.lazy_string
1760 provides a simple way to create objects of this type.
1762 ** The fields returned by gdb.Type.fields now have an
1763 `is_base_class' attribute.
1765 ** The new method gdb.Type.range returns the range of an array type.
1767 ** The new method gdb.parse_and_eval can be used to parse and
1768 evaluate an expression.
1770 * New remote packets
1773 Define a trace state variable.
1776 Get the current value of a trace state variable.
1779 Set desired tracing behavior upon disconnection.
1782 Set the trace buffer to be linear or circular.
1785 Get data about the tracepoints currently in use.
1789 Process record now works correctly with hardware watchpoints.
1791 Multiple bug fixes have been made to the mips-irix port, making it
1792 much more reliable. In particular:
1793 - Debugging threaded applications is now possible again. Previously,
1794 GDB would hang while starting the program, or while waiting for
1795 the program to stop at a breakpoint.
1796 - Attaching to a running process no longer hangs.
1797 - An error occurring while loading a core file has been fixed.
1798 - Changing the value of the PC register now works again. This fixes
1799 problems observed when using the "jump" command, or when calling
1800 a function from GDB, or even when assigning a new value to $pc.
1801 - With the "finish" and "return" commands, the return value for functions
1802 returning a small array is now correctly printed.
1803 - It is now possible to break on shared library code which gets executed
1804 during a shared library init phase (code executed while executing
1805 their .init section). Previously, the breakpoint would have no effect.
1806 - GDB is now able to backtrace through the signal handler for
1807 non-threaded programs.
1809 PIE (Position Independent Executable) programs debugging is now supported.
1810 This includes debugging execution of PIC (Position Independent Code) shared
1811 libraries although for that, it should be possible to run such libraries as an
1814 *** Changes in GDB 7.0
1816 * GDB now has an interface for JIT compilation. Applications that
1817 dynamically generate code can create symbol files in memory and register
1818 them with GDB. For users, the feature should work transparently, and
1819 for JIT developers, the interface is documented in the GDB manual in the
1820 "JIT Compilation Interface" chapter.
1822 * Tracepoints may now be conditional. The syntax is as for
1823 breakpoints; either an "if" clause appended to the "trace" command,
1824 or the "condition" command is available. GDB sends the condition to
1825 the target for evaluation using the same bytecode format as is used
1826 for tracepoint actions.
1828 * The disassemble command now supports: an optional /r modifier, print the
1829 raw instructions in hex as well as in symbolic form, and an optional /m
1830 modifier to print mixed source+assembly.
1832 * Process record and replay
1834 In a architecture environment that supports ``process record and
1835 replay'', ``process record and replay'' target can record a log of
1836 the process execution, and replay it with both forward and reverse
1839 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1840 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1841 set execution-direction {forward|reverse}, for targets that support
1844 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1845 feature is available with a native GDB running on kernel version
1848 * GDB now has support for multi-byte and wide character sets on the
1849 target. Strings whose character type is wchar_t, char16_t, or
1850 char32_t are now correctly printed. GDB supports wide- and unicode-
1851 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1852 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1853 `printf'. This feature requires iconv to work properly; if your
1854 system does not have a working iconv, GDB can use GNU libiconv. See
1855 the installation instructions for more information.
1857 * GDB now supports automatic retrieval of shared library files from
1858 remote targets. To use this feature, specify a system root that begins
1859 with the `remote:' prefix, either via the `set sysroot' command or via
1860 the `--with-sysroot' configure-time option.
1862 * "info sharedlibrary" now takes an optional regex of libraries to show,
1863 and it now reports if a shared library has no debugging information.
1865 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1866 now complete on file names.
1868 * When completing in expressions, gdb will attempt to limit
1869 completions to allowable structure or union fields, where appropriate.
1870 For instance, consider:
1872 # struct example { int f1; double f2; };
1873 # struct example variable;
1876 If the user types TAB at the end of this command line, the available
1877 completions will be "f1" and "f2".
1879 * Inlined functions are now supported. They show up in backtraces, and
1880 the "step", "next", and "finish" commands handle them automatically.
1882 * GDB now supports the token-splicing (##) and stringification (#)
1883 operators when expanding macros. It also supports variable-arity
1886 * GDB now supports inspecting extra signal information, exported by
1887 the new $_siginfo convenience variable. The feature is currently
1888 implemented on linux ARM, i386 and amd64.
1890 * GDB can now display the VFP floating point registers and NEON vector
1891 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1892 can provide these registers (requires Linux 2.6.30 or later). Remote
1893 and simulator targets may also provide them.
1895 * New remote packets
1898 Search memory for a sequence of bytes.
1901 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1902 operation over reliable transport links. Use of this packet is
1903 controlled by the `set remote noack-packet' command.
1906 Kill the process with the specified process ID. Use this in preference
1907 to `k' when multiprocess protocol extensions are supported.
1910 Obtains additional operating system information
1914 Read or write additional signal information.
1916 * Removed remote protocol undocumented extension
1918 An undocumented extension to the remote protocol's `S' stop reply
1919 packet that permited the stub to pass a process id was removed.
1920 Remote servers should use the `T' stop reply packet instead.
1922 * GDB now supports multiple function calling conventions according to the
1923 DWARF-2 DW_AT_calling_convention function attribute.
1925 * The SH target utilizes the aforementioned change to distinguish between gcc
1926 and Renesas calling convention. It also adds the new CLI commands
1927 `set/show sh calling-convention'.
1929 * GDB can now read compressed debug sections, as produced by GNU gold
1930 with the --compress-debug-sections=zlib flag.
1932 * 64-bit core files are now supported on AIX.
1934 * Thread switching is now supported on Tru64.
1936 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1937 which will be allocated using malloc later in program execution.
1939 * The qXfer:libraries:read remote procotol packet now allows passing a
1940 list of section offsets.
1942 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1943 conditions handling signals delivered during attach or thread creation
1944 have also been fixed.
1946 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1947 From the user's standpoint, all unqualified instances of True and False
1948 are treated as the standard definitions, regardless of context.
1950 * GDB now parses C++ symbol and type names more flexibly. For
1953 template<typename T> class C { };
1956 GDB will now correctly handle all of:
1958 ptype C<char const *>
1959 ptype C<char const*>
1960 ptype C<const char *>
1961 ptype C<const char*>
1963 * New features in the GDB remote stub, gdbserver
1965 - The "--wrapper" command-line argument tells gdbserver to use a
1966 wrapper program to launch programs for debugging.
1968 - On PowerPC and S/390 targets, it is now possible to use a single
1969 gdbserver executable to debug both 32-bit and 64-bit programs.
1970 (This requires gdbserver itself to be built as a 64-bit executable.)
1972 - gdbserver uses the new noack protocol mode for TCP connections to
1973 reduce communications latency, if also supported and enabled in GDB.
1975 - Support for the sparc64-linux-gnu target is now included in
1978 - The amd64-linux build of gdbserver now supports debugging both
1979 32-bit and 64-bit programs.
1981 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1982 now support hardware watchpoints, and will use them automatically
1987 GDB now has support for scripting using Python. Whether this is
1988 available is determined at configure time.
1990 New GDB commands can now be written in Python.
1992 * Ada tasking support
1994 Ada tasks can now be inspected in GDB. The following commands have
1998 Print the list of Ada tasks.
2000 Print detailed information about task number N.
2002 Print the task number of the current task.
2004 Switch the context of debugging to task number N.
2006 * Support for user-defined prefixed commands. The "define" command can
2007 add new commands to existing prefixes, e.g. "target".
2009 * Multi-inferior, multi-process debugging.
2011 GDB now has generalized support for multi-inferior debugging. See
2012 "Debugging Multiple Inferiors" in the manual for more information.
2013 Although availability still depends on target support, the command
2014 set is more uniform now. The GNU/Linux specific multi-forks support
2015 has been migrated to this new framework. This implied some user
2016 visible changes; see "New commands" and also "Removed commands"
2019 * Target descriptions can now describe the target OS ABI. See the
2020 "Target Description Format" section in the user manual for more
2023 * Target descriptions can now describe "compatible" architectures
2024 to indicate that the target can execute applications for a different
2025 architecture in addition to those for the main target architecture.
2026 See the "Target Description Format" section in the user manual for
2029 * Multi-architecture debugging.
2031 GDB now includes general supports for debugging applications on
2032 hybrid systems that use more than one single processor architecture
2033 at the same time. Each such hybrid architecture still requires
2034 specific support to be added. The only hybrid architecture supported
2035 in this version of GDB is the Cell Broadband Engine.
2037 * GDB now supports integrated debugging of Cell/B.E. applications that
2038 use both the PPU and SPU architectures. To enable support for hybrid
2039 Cell/B.E. debugging, you need to configure GDB to support both the
2040 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2041 --enable-targets configure option.
2043 * Non-stop mode debugging.
2045 For some targets, GDB now supports an optional mode of operation in
2046 which you can examine stopped threads while other threads continue
2047 to execute freely. This is referred to as non-stop mode, with the
2048 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2049 section in the user manual for more information.
2051 To be able to support remote non-stop debugging, a remote stub needs
2052 to implement the non-stop mode remote protocol extensions, as
2053 described in the "Remote Non-Stop" section of the user manual. The
2054 GDB remote stub, gdbserver, has been adjusted to support these
2055 extensions on linux targets.
2057 * New commands (for set/show, see "New options" below)
2059 catch syscall [NAME(S) | NUMBER(S)]
2060 Catch system calls. Arguments, which should be names of system
2061 calls or their numbers, mean catch only those syscalls. Without
2062 arguments, every syscall will be caught. When the inferior issues
2063 any of the specified syscalls, GDB will stop and announce the system
2064 call, both when it is called and when its call returns. This
2065 feature is currently available with a native GDB running on the
2066 Linux Kernel, under the following architectures: x86, x86_64,
2067 PowerPC and PowerPC64.
2069 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2071 Search memory for a sequence of bytes.
2073 maint set python print-stack
2074 maint show python print-stack
2075 Show a stack trace when an error is encountered in a Python script.
2078 Invoke CODE by passing it to the Python interpreter.
2083 These allow macros to be defined, undefined, and listed
2087 Show operating system information about processes.
2090 List the inferiors currently under GDB's control.
2093 Switch focus to inferior number NUM.
2096 Detach from inferior number NUM.
2099 Kill inferior number NUM.
2103 set spu stop-on-load
2104 show spu stop-on-load
2105 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2107 set spu auto-flush-cache
2108 show spu auto-flush-cache
2109 Control whether to automatically flush the software-managed cache
2110 during Cell/B.E. debugging.
2112 set sh calling-convention
2113 show sh calling-convention
2114 Control the calling convention used when calling SH target functions.
2117 show debug timestamp
2118 Control display of timestamps with GDB debugging output.
2120 set disassemble-next-line
2121 show disassemble-next-line
2122 Control display of disassembled source lines or instructions when
2125 set remote noack-packet
2126 show remote noack-packet
2127 Set/show the use of remote protocol QStartNoAckMode packet. See above
2128 under "New remote packets."
2130 set remote query-attached-packet
2131 show remote query-attached-packet
2132 Control use of remote protocol `qAttached' (query-attached) packet.
2134 set remote read-siginfo-object
2135 show remote read-siginfo-object
2136 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2139 set remote write-siginfo-object
2140 show remote write-siginfo-object
2141 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2144 set remote reverse-continue
2145 show remote reverse-continue
2146 Control use of remote protocol 'bc' (reverse-continue) packet.
2148 set remote reverse-step
2149 show remote reverse-step
2150 Control use of remote protocol 'bs' (reverse-step) packet.
2152 set displaced-stepping
2153 show displaced-stepping
2154 Control displaced stepping mode. Displaced stepping is a way to
2155 single-step over breakpoints without removing them from the debuggee.
2156 Also known as "out-of-line single-stepping".
2159 show debug displaced
2160 Control display of debugging info for displaced stepping.
2162 maint set internal-error
2163 maint show internal-error
2164 Control what GDB does when an internal error is detected.
2166 maint set internal-warning
2167 maint show internal-warning
2168 Control what GDB does when an internal warning is detected.
2173 Use a wrapper program to launch programs for debugging.
2175 set multiple-symbols (all|ask|cancel)
2176 show multiple-symbols
2177 The value of this variable can be changed to adjust the debugger behavior
2178 when an expression or a breakpoint location contains an ambiguous symbol
2179 name (an overloaded function name, for instance).
2181 set breakpoint always-inserted
2182 show breakpoint always-inserted
2183 Keep breakpoints always inserted in the target, as opposed to inserting
2184 them when resuming the target, and removing them when the target stops.
2185 This option can improve debugger performance on slow remote targets.
2187 set arm fallback-mode (arm|thumb|auto)
2188 show arm fallback-mode
2189 set arm force-mode (arm|thumb|auto)
2191 These commands control how ARM GDB determines whether instructions
2192 are ARM or Thumb. The default for both settings is auto, which uses
2193 the current CPSR value for instructions without symbols; previous
2194 versions of GDB behaved as if "set arm fallback-mode arm".
2196 set disable-randomization
2197 show disable-randomization
2198 Standalone programs run with the virtual address space randomization enabled
2199 by default on some platforms. This option keeps the addresses stable across
2200 multiple debugging sessions.
2204 Control whether other threads are stopped or not when some thread hits
2209 Requests that asynchronous execution is enabled in the target, if available.
2210 In this case, it's possible to resume target in the background, and interact
2211 with GDB while the target is running. "show target-async" displays the
2212 current state of asynchronous execution of the target.
2214 set target-wide-charset
2215 show target-wide-charset
2216 The target-wide-charset is the name of the character set that GDB
2217 uses when printing characters whose type is wchar_t.
2219 set tcp auto-retry (on|off)
2221 set tcp connect-timeout
2222 show tcp connect-timeout
2223 These commands allow GDB to retry failed TCP connections to a remote stub
2224 with a specified timeout period; this is useful if the stub is launched
2225 in parallel with GDB but may not be ready to accept connections immediately.
2227 set libthread-db-search-path
2228 show libthread-db-search-path
2229 Control list of directories which GDB will search for appropriate
2232 set schedule-multiple (on|off)
2233 show schedule-multiple
2234 Allow GDB to resume all threads of all processes or only threads of
2235 the current process.
2239 Use more aggressive caching for accesses to the stack. This improves
2240 performance of remote debugging (particularly backtraces) without
2241 affecting correctness.
2243 set interactive-mode (on|off|auto)
2244 show interactive-mode
2245 Control whether GDB runs in interactive mode (on) or not (off).
2246 When in interactive mode, GDB waits for the user to answer all
2247 queries. Otherwise, GDB does not wait and assumes the default
2248 answer. When set to auto (the default), GDB determines which
2249 mode to use based on the stdin settings.
2254 For program forks, this is replaced by the new more generic `info
2255 inferiors' command. To list checkpoints, you can still use the
2256 `info checkpoints' command, which was an alias for the `info forks'
2260 Replaced by the new `inferior' command. To switch between
2261 checkpoints, you can still use the `restart' command, which was an
2262 alias for the `fork' command.
2265 This is removed, since some targets don't have a notion of
2266 processes. To switch between processes, you can still use the
2267 `inferior' command using GDB's own inferior number.
2270 For program forks, this is replaced by the new more generic `kill
2271 inferior' command. To delete a checkpoint, you can still use the
2272 `delete checkpoint' command, which was an alias for the `delete
2276 For program forks, this is replaced by the new more generic `detach
2277 inferior' command. To detach a checkpoint, you can still use the
2278 `detach checkpoint' command, which was an alias for the `detach
2281 * New native configurations
2283 x86/x86_64 Darwin i[34567]86-*-darwin*
2285 x86_64 MinGW x86_64-*-mingw*
2289 Lattice Mico32 lm32-*
2290 x86 DICOS i[34567]86-*-dicos*
2291 x86_64 DICOS x86_64-*-dicos*
2294 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2295 (mingw32ce) debugging.
2301 These commands were actually not implemented on any target.
2303 *** Changes in GDB 6.8
2305 * New native configurations
2307 NetBSD/hppa hppa*-*netbsd*
2308 Xtensa GNU/Linux xtensa*-*-linux*
2312 NetBSD/hppa hppa*-*-netbsd*
2313 Xtensa GNU/Lunux xtensa*-*-linux*
2315 * Change in command line behavior -- corefiles vs. process ids.
2317 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2318 attaching to process NUMBER fails, GDB no longer attempts to open a
2319 core file named NUMBER. Attaching to a program using the -c option
2320 is no longer supported. Instead, use the '-p' or '--pid' options.
2322 * GDB can now be built as a native debugger for debugging Windows x86
2323 (mingw32) Portable Executable (PE) programs.
2325 * Pending breakpoints no longer change their number when their address
2328 * GDB now supports breakpoints with multiple locations,
2329 including breakpoints on C++ constructors, inside C++ templates,
2330 and in inlined functions.
2332 * GDB's ability to debug optimized code has been improved. GDB more
2333 accurately identifies function bodies and lexical blocks that occupy
2334 more than one contiguous range of addresses.
2336 * Target descriptions can now describe registers for PowerPC.
2338 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2339 registers on PowerPC targets.
2341 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2342 targets even when the libthread_db library is not available.
2344 * The GDB remote stub, gdbserver, now supports the new file transfer
2345 commands (remote put, remote get, and remote delete).
2347 * The GDB remote stub, gdbserver, now supports run and attach in
2348 extended-remote mode.
2350 * hppa*64*-*-hpux11* target broken
2351 The debugger is unable to start a program and fails with the following
2352 error: "Error trying to get information about dynamic linker".
2353 The gdb-6.7 release is also affected.
2355 * GDB now supports the --enable-targets= configure option to allow
2356 building a single GDB executable that supports multiple remote
2357 target architectures.
2359 * GDB now supports debugging C and C++ programs which use the
2360 Decimal Floating Point extension. In addition, the PowerPC target
2361 now has a set of pseudo-registers to inspect decimal float values
2362 stored in two consecutive float registers.
2364 * The -break-insert MI command can optionally create pending
2367 * Improved support for debugging Ada
2368 Many improvements to the Ada language support have been made. These
2370 - Better support for Ada2005 interface types
2371 - Improved handling of arrays and slices in general
2372 - Better support for Taft-amendment types
2373 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2375 - Improved command completion in Ada
2378 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2383 set print frame-arguments (all|scalars|none)
2384 show print frame-arguments
2385 The value of this variable can be changed to control which argument
2386 values should be printed by the debugger when displaying a frame.
2391 Transfer files to and from a remote target, and delete remote files.
2398 Transfer files to and from a remote target, and delete remote files.
2400 * New remote packets
2407 Open, close, read, write, and delete files on the remote system.
2410 Attach to an existing process on the remote system, in extended-remote
2414 Run a new process on the remote system, in extended-remote mode.
2416 *** Changes in GDB 6.7
2418 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2419 bfd, libiberty and opcodes, as revealed by static analysis donated by
2420 Coverity, Inc. (http://scan.coverity.com).
2422 * When looking up multiply-defined global symbols, GDB will now prefer the
2423 symbol definition in the current shared library if it was built using the
2424 -Bsymbolic linker option.
2426 * When the Text User Interface (TUI) is not configured, GDB will now
2427 recognize the -tui command-line option and print a message that the TUI
2430 * The GDB remote stub, gdbserver, now has lower overhead for high
2431 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2433 * GDB for MIPS targets now autodetects whether a remote target provides
2434 32-bit or 64-bit register values.
2436 * Support for C++ member pointers has been improved.
2438 * GDB now understands XML target descriptions, which specify the
2439 target's overall architecture. GDB can read a description from
2440 a local file or over the remote serial protocol.
2442 * Vectors of single-byte data use a new integer type which is not
2443 automatically displayed as character or string data.
2445 * The /s format now works with the print command. It displays
2446 arrays of single-byte integers and pointers to single-byte integers
2449 * Target descriptions can now describe target-specific registers,
2450 for architectures which have implemented the support (currently
2451 only ARM, M68K, and MIPS).
2453 * GDB and the GDB remote stub, gdbserver, now support the XScale
2456 * The GDB remote stub, gdbserver, has been updated to support
2457 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2458 has been rewritten to use the standard GDB remote protocol.
2460 * GDB can now step into C++ functions which are called through thunks.
2462 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2464 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2465 layout. It also supports a TextSeg= and DataSeg= response when only
2466 segment base addresses (rather than offsets) are available.
2468 * The /i format now outputs any trailing branch delay slot instructions
2469 immediately following the last instruction within the count specified.
2471 * The GDB remote protocol "T" stop reply packet now supports a
2472 "library" response. Combined with the new "qXfer:libraries:read"
2473 packet, this response allows GDB to debug shared libraries on targets
2474 where the operating system manages the list of loaded libraries (e.g.
2475 Windows and SymbianOS).
2477 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2478 (DLLs) on Windows and Windows CE targets.
2480 * GDB now supports a faster verification that a .debug file matches its binary
2481 according to its build-id signature, if the signature is present.
2487 Enable or disable hardware flow control (RTS/CTS) on the serial port
2488 when debugging using remote targets.
2490 set mem inaccessible-by-default
2491 show mem inaccessible-by-default
2492 If the target supplies a memory map, for instance via the remote
2493 protocol's "qXfer:memory-map:read" packet, setting this variable
2494 prevents GDB from accessing memory outside the memory map. This
2495 is useful for targets with memory mapped registers or which react
2496 badly to accesses of unmapped address space.
2498 set breakpoint auto-hw
2499 show breakpoint auto-hw
2500 If the target supplies a memory map, for instance via the remote
2501 protocol's "qXfer:memory-map:read" packet, setting this variable
2502 lets GDB use hardware breakpoints automatically for memory regions
2503 where it can not use software breakpoints. This covers both the
2504 "break" command and internal breakpoints used for other commands
2505 including "next" and "finish".
2508 catch exception unhandled
2509 Stop the program execution when Ada exceptions are raised.
2512 Stop the program execution when an Ada assertion failed.
2516 Set an alternate system root for target files. This is a more
2517 general version of "set solib-absolute-prefix", which is now
2518 an alias to "set sysroot".
2521 Provide extended SPU facility status information. This set of
2522 commands is available only when debugging the Cell/B.E. SPU
2525 * New native configurations
2527 OpenBSD/sh sh*-*openbsd*
2530 unset tdesc filename
2532 Use the specified local file as an XML target description, and do
2533 not query the target for its built-in description.
2537 OpenBSD/sh sh*-*-openbsd*
2538 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2539 Toshiba Media Processor mep-elf
2541 * New remote packets
2544 Ignore the specified signals; pass them directly to the debugged program
2545 without stopping other threads or reporting them to GDB.
2547 qXfer:features:read:
2548 Read an XML target description from the target, which describes its
2553 Read or write contents of an spufs file on the target system. These
2554 packets are available only on the Cell/B.E. SPU architecture.
2556 qXfer:libraries:read:
2557 Report the loaded shared libraries. Combined with new "T" packet
2558 response, this packet allows GDB to debug shared libraries on
2559 targets where the operating system manages the list of loaded
2560 libraries (e.g. Windows and SymbianOS).
2564 Support for these obsolete configurations has been removed.
2572 i[34567]86-*-lynxos*
2573 i[34567]86-*-netware*
2574 i[34567]86-*-sco3.2v5*
2575 i[34567]86-*-sco3.2v4*
2577 i[34567]86-*-sysv4.2*
2580 i[34567]86-*-unixware2*
2581 i[34567]86-*-unixware*
2590 * Other removed features
2597 Various m68k-only ROM monitors.
2604 Various Renesas ROM monitors and debugging interfaces for SH and
2609 Support for a Macraigor serial interface to on-chip debugging.
2610 GDB does not directly support the newer parallel or USB
2615 A debug information format. The predecessor to DWARF 2 and
2616 DWARF 3, which are still supported.
2618 Support for the HP aCC compiler on HP-UX/PA-RISC
2620 SOM-encapsulated symbolic debugging information, automatic
2621 invocation of pxdb, and the aCC custom C++ ABI. This does not
2622 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2623 with aCC can still be debugged on an assembly level.
2625 MIPS ".pdr" sections
2627 A MIPS-specific format used to describe stack frame layout
2628 in debugging information.
2632 GDB could work with an older version of Guile to debug
2633 the interpreter and Scheme programs running in it.
2635 set mips stack-arg-size
2636 set mips saved-gpreg-size
2638 Use "set mips abi" to control parameter passing for MIPS.
2640 *** Changes in GDB 6.6
2645 Cell Broadband Engine SPU spu-elf
2647 * GDB can now be configured as a cross-debugger targeting native Windows
2648 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2649 running on a Windows system over TCP/IP to debug Windows programs.
2651 * The GDB remote stub, gdbserver, has been updated to support Windows and
2652 Cygwin debugging. Both single-threaded and multi-threaded programs are
2655 * The "set trust-readonly-sections" command works again. This command was
2656 broken in GDB 6.3, 6.4, and 6.5.
2658 * The "load" command now supports writing to flash memory, if the remote
2659 stub provides the required support.
2661 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2662 longer requires symbolic debug information (e.g. DWARF-2).
2667 unset substitute-path
2668 show substitute-path
2669 Manage a list of substitution rules that GDB uses to rewrite the name
2670 of the directories where the sources are located. This can be useful
2671 for instance when the sources were moved to a different location
2672 between compilation and debugging.
2676 Print each CLI command as it is executed. Each command is prefixed with
2677 a number of `+' symbols representing the nesting depth.
2678 The source command now has a `-v' option to enable the same feature.
2682 The ARM Demon monitor support (RDP protocol, "target rdp").
2684 Kernel Object Display, an embedded debugging feature which only worked with
2685 an obsolete version of Cisco IOS.
2687 The 'set download-write-size' and 'show download-write-size' commands.
2689 * New remote packets
2692 Tell a stub about GDB client features, and request remote target features.
2693 The first feature implemented is PacketSize, which allows the target to
2694 specify the size of packets it can handle - to minimize the number of
2695 packets required and improve performance when connected to a remote
2699 Fetch an OS auxilliary vector from the remote stub. This packet is a
2700 more efficient replacement for qPart:auxv:read.
2702 qXfer:memory-map:read:
2703 Fetch a memory map from the remote stub, including information about
2704 RAM, ROM, and flash memory devices.
2709 Erase and program a flash memory device.
2711 * Removed remote packets
2714 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2715 used it, and only gdbserver implemented it.
2717 *** Changes in GDB 6.5
2721 Renesas M32C/M16C m32c-elf
2723 Morpho Technologies ms1 ms1-elf
2727 init-if-undefined Initialize a convenience variable, but
2728 only if it doesn't already have a value.
2730 The following commands are presently only implemented for native GNU/Linux:
2732 checkpoint Save a snapshot of the program state.
2734 restart <n> Return the program state to a
2735 previously saved state.
2737 info checkpoints List currently saved checkpoints.
2739 delete-checkpoint <n> Delete a previously saved checkpoint.
2741 set|show detach-on-fork Tell gdb whether to detach from a newly
2742 forked process, or to keep debugging it.
2744 info forks List forks of the user program that
2745 are available to be debugged.
2747 fork <n> Switch to debugging one of several
2748 forks of the user program that are
2749 available to be debugged.
2751 delete-fork <n> Delete a fork from the list of forks
2752 that are available to be debugged (and
2753 kill the forked process).
2755 detach-fork <n> Delete a fork from the list of forks
2756 that are available to be debugged (and
2757 allow the process to continue).
2761 Morpho Technologies ms2 ms1-elf
2763 * Improved Windows host support
2765 GDB now builds as a cross debugger hosted on i686-mingw32, including
2766 native console support, and remote communications using either
2767 network sockets or serial ports.
2769 * Improved Modula-2 language support
2771 GDB can now print most types in the Modula-2 syntax. This includes:
2772 basic types, set types, record types, enumerated types, range types,
2773 pointer types and ARRAY types. Procedure var parameters are correctly
2774 printed and hexadecimal addresses and character constants are also
2775 written in the Modula-2 syntax. Best results can be obtained by using
2776 GNU Modula-2 together with the -gdwarf-2 command line option.
2780 The ARM rdi-share module.
2782 The Netware NLM debug server.
2784 *** Changes in GDB 6.4
2786 * New native configurations
2788 OpenBSD/arm arm*-*-openbsd*
2789 OpenBSD/mips64 mips64-*-openbsd*
2793 Morpho Technologies ms1 ms1-elf
2795 * New command line options
2797 --batch-silent As for --batch, but totally silent.
2798 --return-child-result The debugger will exist with the same value
2799 the child (debugged) program exited with.
2800 --eval-command COMMAND, -ex COMMAND
2801 Execute a single GDB CLI command. This may be
2802 specified multiple times and in conjunction
2803 with the --command (-x) option.
2805 * Deprecated commands removed
2807 The following commands, that were deprecated in 2000, have been
2811 set|show arm disassembly-flavor set|show arm disassembler
2812 othernames set arm disassembler
2813 set|show remotedebug set|show debug remote
2814 set|show archdebug set|show debug arch
2815 set|show eventdebug set|show debug event
2818 * New BSD user-level threads support
2820 It is now possible to debug programs using the user-level threads
2821 library on OpenBSD and FreeBSD. Currently supported (target)
2824 FreeBSD/amd64 x86_64-*-freebsd*
2825 FreeBSD/i386 i386-*-freebsd*
2826 OpenBSD/i386 i386-*-openbsd*
2828 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2829 are not yet supported.
2831 * New support for Matsushita MN10300 w/sim added
2832 (Work in progress). mn10300-elf.
2834 * REMOVED configurations and files
2836 VxWorks and the XDR protocol *-*-vxworks
2837 Motorola MCORE mcore-*-*
2838 National Semiconductor NS32000 ns32k-*-*
2840 * New "set print array-indexes" command
2842 After turning this setting "on", GDB prints the index of each element
2843 when displaying arrays. The default is "off" to preserve the previous
2846 * VAX floating point support
2848 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2850 * User-defined command support
2852 In addition to using $arg0..$arg9 for argument passing, it is now possible
2853 to use $argc to determine now many arguments have been passed. See the
2854 section on user-defined commands in the user manual for more information.
2856 *** Changes in GDB 6.3:
2858 * New command line option
2860 GDB now accepts -l followed by a number to set the timeout for remote
2863 * GDB works with GCC -feliminate-dwarf2-dups
2865 GDB now supports a more compact representation of DWARF-2 debug
2866 information using DW_FORM_ref_addr references. These are produced
2867 by GCC with the option -feliminate-dwarf2-dups and also by some
2868 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2869 to use -feliminate-dwarf2-dups.
2871 * Internationalization
2873 When supported by the host system, GDB will be built with
2874 internationalization (libintl). The task of marking up the sources is
2875 continued, we're looking forward to our first translation.
2879 Initial support for debugging programs compiled with the GNAT
2880 implementation of the Ada programming language has been integrated
2881 into GDB. In this release, support is limited to expression evaluation.
2883 * New native configurations
2885 GNU/Linux/m32r m32r-*-linux-gnu
2889 GDB's remote protocol now includes support for the 'p' packet. This
2890 packet is used to fetch individual registers from a remote inferior.
2892 * END-OF-LIFE registers[] compatibility module
2894 GDB's internal register infrastructure has been completely rewritten.
2895 The new infrastructure making possible the implementation of key new
2896 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2899 GDB 6.3 will be the last release to include the the registers[]
2900 compatibility module that allowed out-of-date configurations to
2901 continue to work. This change directly impacts the following
2911 powerpc bdm protocol
2913 Unless there is activity to revive these configurations, they will be
2914 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2916 * OBSOLETE configurations and files
2918 Configurations that have been declared obsolete in this release have
2919 been commented out. Unless there is activity to revive these
2920 configurations, the next release of GDB will have their sources
2921 permanently REMOVED.
2930 *** Changes in GDB 6.2.1:
2932 * MIPS `break main; run' gave an heuristic-fence-post warning
2934 When attempting to run even a simple program, a warning about
2935 heuristic-fence-post being hit would be reported. This problem has
2938 * MIPS IRIX 'long double' crashed GDB
2940 When examining a long double variable, GDB would get a segmentation
2941 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2942 IRIX long double values).
2946 A bug in the VAX stack code was causing problems with the "next"
2947 command. This problem has been fixed.
2949 *** Changes in GDB 6.2:
2951 * Fix for ``many threads''
2953 On GNU/Linux systems that use the NPTL threads library, a program
2954 rapidly creating and deleting threads would confuse GDB leading to the
2957 ptrace: No such process.
2958 thread_db_get_info: cannot get thread info: generic error
2960 This problem has been fixed.
2962 * "-async" and "-noasync" options removed.
2964 Support for the broken "-noasync" option has been removed (it caused
2967 * New ``start'' command.
2969 This command runs the program until the begining of the main procedure.
2971 * New BSD Kernel Data Access Library (libkvm) interface
2973 Using ``target kvm'' it is now possible to debug kernel core dumps and
2974 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2975 platforms. Currently supported (native-only) configurations are:
2977 FreeBSD/amd64 x86_64-*-freebsd*
2978 FreeBSD/i386 i?86-*-freebsd*
2979 NetBSD/i386 i?86-*-netbsd*
2980 NetBSD/m68k m68*-*-netbsd*
2981 NetBSD/sparc sparc-*-netbsd*
2982 OpenBSD/amd64 x86_64-*-openbsd*
2983 OpenBSD/i386 i?86-*-openbsd*
2984 OpenBSD/m68k m68*-openbsd*
2985 OpenBSD/sparc sparc-*-openbsd*
2987 * Signal trampoline code overhauled
2989 Many generic problems with GDB's signal handling code have been fixed.
2990 These include: backtraces through non-contiguous stacks; recognition
2991 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2992 call; backtrace through a signal trampoline; step into and out of
2993 signal handlers; and single-stepping in the signal trampoline.
2995 Please note that kernel bugs are a limiting factor here. These
2996 features have been shown to work on an s390 GNU/Linux system that
2997 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2999 * Cygwin support for DWARF 2 added.
3001 * New native configurations
3003 GNU/Linux/hppa hppa*-*-linux*
3004 OpenBSD/hppa hppa*-*-openbsd*
3005 OpenBSD/m68k m68*-*-openbsd*
3006 OpenBSD/m88k m88*-*-openbsd*
3007 OpenBSD/powerpc powerpc-*-openbsd*
3008 NetBSD/vax vax-*-netbsd*
3009 OpenBSD/vax vax-*-openbsd*
3011 * END-OF-LIFE frame compatibility module
3013 GDB's internal frame infrastructure has been completely rewritten.
3014 The new infrastructure making it possible to support key new features
3015 including DWARF 2 Call Frame Information. To aid in the task of
3016 migrating old configurations to this new infrastructure, a
3017 compatibility module, that allowed old configurations to continue to
3018 work, was also included.
3020 GDB 6.2 will be the last release to include this frame compatibility
3021 module. This change directly impacts the following configurations:
3031 Unless there is activity to revive these configurations, they will be
3032 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3034 * REMOVED configurations and files
3036 Sun 3, running SunOS 3 m68*-*-sunos3*
3037 Sun 3, running SunOS 4 m68*-*-sunos4*
3038 Sun 2, running SunOS 3 m68000-*-sunos3*
3039 Sun 2, running SunOS 4 m68000-*-sunos4*
3040 Motorola 680x0 running LynxOS m68*-*-lynxos*
3041 AT&T 3b1/Unix pc m68*-att-*
3042 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3043 decstation mips-dec-* mips-little-*
3044 riscos mips-*-riscos* mips-*-sysv*
3045 sonymips mips-sony-*
3046 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3048 *** Changes in GDB 6.1.1:
3050 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3052 The TUI (Text-mode User Interface) is now built as part of a default
3053 GDB configuration. It is enabled by either selecting the TUI with the
3054 command line option "-i=tui" or by running the separate "gdbtui"
3055 program. For more information on the TUI, see the manual "Debugging
3058 * Pending breakpoint support (also included in GDB 6.1)
3060 Support has been added to allow you to specify breakpoints in shared
3061 libraries that have not yet been loaded. If a breakpoint location
3062 cannot be found, and the "breakpoint pending" option is set to auto,
3063 GDB queries you if you wish to make the breakpoint pending on a future
3064 shared-library load. If and when GDB resolves the breakpoint symbol,
3065 the pending breakpoint is removed as one or more regular breakpoints
3068 Pending breakpoints are very useful for GCJ Java debugging.
3070 * Fixed ISO-C build problems
3072 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3073 non ISO-C code that stopped them being built using a more strict ISO-C
3074 compiler (e.g., IBM's C compiler).
3076 * Fixed build problem on IRIX 5
3078 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3079 wasn't able to compile compile on an IRIX 5 system.
3081 * Added execute permission to gdb/gdbserver/configure
3083 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3084 permission. This bug would cause configure to fail on a number of
3085 systems (Solaris, IRIX). Ref: server/519.
3087 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3089 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3090 has been updated to use constant array sizes.
3092 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3094 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3095 its generated DWARF Call Frame Info. This encoding was causing GDB to
3096 panic, that panic has been fixed. Ref: gdb/1628.
3098 * Fixed a problem when examining parameters in shared library code.
3100 When examining parameters in optimized shared library code generated
3101 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3102 not available''. GDB now correctly displays the variable's value.
3104 *** Changes in GDB 6.1:
3106 * Removed --with-mmalloc
3108 Support for the mmalloc memory manager has been removed, as it
3109 conflicted with the internal gdb byte cache.
3111 * Changes in AMD64 configurations
3113 The AMD64 target now includes the %cs and %ss registers. As a result
3114 the AMD64 remote protocol has changed; this affects the floating-point
3115 and SSE registers. If you rely on those registers for your debugging,
3116 you should upgrade gdbserver on the remote side.
3118 * Revised SPARC target
3120 The SPARC target has been completely revised, incorporating the
3121 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3122 support for LynxOS and SunOS 4 has been dropped. Calling functions
3123 from within GDB on operating systems with a non-executable stack
3124 (Solaris, OpenBSD) now works.
3128 GDB has a new C++ demangler which does a better job on the mangled
3129 names generated by current versions of g++. It also runs faster, so
3130 with this and other changes gdb should now start faster on large C++
3133 * DWARF 2 Location Expressions
3135 GDB support for location expressions has been extended to support function
3136 arguments and frame bases. Older versions of GDB could crash when they
3139 * C++ nested types and namespaces
3141 GDB's support for nested types and namespaces in C++ has been
3142 improved, especially if you use the DWARF 2 debugging format. (This
3143 is the default for recent versions of GCC on most platforms.)
3144 Specifically, if you have a class "Inner" defined within a class or
3145 namespace "Outer", then GDB realizes that the class's name is
3146 "Outer::Inner", not simply "Inner". This should greatly reduce the
3147 frequency of complaints about not finding RTTI symbols. In addition,
3148 if you are stopped at inside of a function defined within a namespace,
3149 GDB modifies its name lookup accordingly.
3151 * New native configurations
3153 NetBSD/amd64 x86_64-*-netbsd*
3154 OpenBSD/amd64 x86_64-*-openbsd*
3155 OpenBSD/alpha alpha*-*-openbsd*
3156 OpenBSD/sparc sparc-*-openbsd*
3157 OpenBSD/sparc64 sparc64-*-openbsd*
3159 * New debugging protocols
3161 M32R with SDI protocol m32r-*-elf*
3163 * "set prompt-escape-char" command deleted.
3165 The command "set prompt-escape-char" has been deleted. This command,
3166 and its very obscure effet on GDB's prompt, was never documented,
3167 tested, nor mentioned in the NEWS file.
3169 * OBSOLETE configurations and files
3171 Configurations that have been declared obsolete in this release have
3172 been commented out. Unless there is activity to revive these
3173 configurations, the next release of GDB will have their sources
3174 permanently REMOVED.
3176 Sun 3, running SunOS 3 m68*-*-sunos3*
3177 Sun 3, running SunOS 4 m68*-*-sunos4*
3178 Sun 2, running SunOS 3 m68000-*-sunos3*
3179 Sun 2, running SunOS 4 m68000-*-sunos4*
3180 Motorola 680x0 running LynxOS m68*-*-lynxos*
3181 AT&T 3b1/Unix pc m68*-att-*
3182 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3183 decstation mips-dec-* mips-little-*
3184 riscos mips-*-riscos* mips-*-sysv*
3185 sonymips mips-sony-*
3186 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3188 * REMOVED configurations and files
3190 SGI Irix-4.x mips-sgi-irix4 or iris4
3191 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3192 Z8000 simulator z8k-zilog-none or z8ksim
3193 Matsushita MN10200 w/simulator mn10200-*-*
3194 H8/500 simulator h8500-hitachi-hms or h8500hms
3195 HP/PA running BSD hppa*-*-bsd*
3196 HP/PA running OSF/1 hppa*-*-osf*
3197 HP/PA Pro target hppa*-*-pro*
3198 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3199 386BSD i[3456]86-*-bsd*
3200 Sequent family i[3456]86-sequent-sysv4*
3201 i[3456]86-sequent-sysv*
3202 i[3456]86-sequent-bsd*
3203 SPARC running LynxOS sparc-*-lynxos*
3204 SPARC running SunOS 4 sparc-*-sunos4*
3205 Tsqware Sparclet sparclet-*-*
3206 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3208 *** Changes in GDB 6.0:
3212 Support for debugging the Objective-C programming language has been
3213 integrated into GDB.
3215 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3217 DWARF 2's Call Frame Information makes available compiler generated
3218 information that more exactly describes the program's run-time stack.
3219 By using this information, GDB is able to provide more robust stack
3222 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3223 have been updated to use a new backtrace mechanism which includes
3224 DWARF 2 CFI support.
3228 GDB's remote protocol has been extended to include support for hosted
3229 file I/O (where the remote target uses GDB's file system). See GDB's
3230 remote protocol documentation for details.
3232 * All targets using the new architecture framework.
3234 All of GDB's targets have been updated to use the new internal
3235 architecture framework. The way is now open for future GDB releases
3236 to include cross-architecture native debugging support (i386 on amd64,
3239 * GNU/Linux's Thread Local Storage (TLS)
3241 GDB now includes support for for the GNU/Linux implementation of
3242 per-thread variables.
3244 * GNU/Linux's Native POSIX Thread Library (NPTL)
3246 GDB's thread code has been updated to work with either the new
3247 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3249 * Separate debug info.
3251 GDB, in conjunction with BINUTILS, now supports a mechanism for
3252 automatically loading debug information from a separate file. Instead
3253 of shipping full debug and non-debug versions of system libraries,
3254 system integrators can now instead ship just the stripped libraries
3255 and optional debug files.
3257 * DWARF 2 Location Expressions
3259 DWARF 2 Location Expressions allow the compiler to more completely
3260 describe the location of variables (even in optimized code) to the
3263 GDB now includes preliminary support for location expressions (support
3264 for DW_OP_piece is still missing).
3268 A number of long standing bugs that caused GDB to die while starting a
3269 Java application have been fixed. GDB's Java support is now
3270 considered "useable".
3272 * GNU/Linux support for fork, vfork, and exec.
3274 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3275 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3278 * GDB supports logging output to a file
3280 There are two new commands, "set logging" and "show logging", which can be
3281 used to capture GDB's output to a file.
3283 * The meaning of "detach" has changed for gdbserver
3285 The "detach" command will now resume the application, as documented. To
3286 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3289 * d10v, m68hc11 `regs' command deprecated
3291 The `info registers' command has been updated so that it displays the
3292 registers using a format identical to the old `regs' command.
3296 A new command, "maint set profile on/off", has been added. This command can
3297 be used to enable or disable profiling while running GDB, to profile a
3298 session or a set of commands. In addition there is a new configure switch,
3299 "--enable-profiling", which will cause GDB to be compiled with profiling
3300 data, for more informative profiling results.
3302 * Default MI syntax changed to "mi2".
3304 The default MI (machine interface) syntax, enabled by the command line
3305 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3306 "mi1", can be enabled by specifying the option "-i=mi1".
3308 Support for the original "mi0" syntax (included in GDB 5.0) has been
3311 Fix for gdb/192: removed extraneous space when displaying frame level.
3312 Fix for gdb/672: update changelist is now output in mi list format.
3313 Fix for gdb/702: a -var-assign that updates the value now shows up
3314 in a subsequent -var-update.
3316 * New native configurations.
3318 FreeBSD/amd64 x86_64-*-freebsd*
3320 * Multi-arched targets.
3322 HP/PA HPUX11 hppa*-*-hpux*
3323 Renesas M32R/D w/simulator m32r-*-elf*
3325 * OBSOLETE configurations and files
3327 Configurations that have been declared obsolete in this release have
3328 been commented out. Unless there is activity to revive these
3329 configurations, the next release of GDB will have their sources
3330 permanently REMOVED.
3332 Z8000 simulator z8k-zilog-none or z8ksim
3333 Matsushita MN10200 w/simulator mn10200-*-*
3334 H8/500 simulator h8500-hitachi-hms or h8500hms
3335 HP/PA running BSD hppa*-*-bsd*
3336 HP/PA running OSF/1 hppa*-*-osf*
3337 HP/PA Pro target hppa*-*-pro*
3338 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3339 Sequent family i[3456]86-sequent-sysv4*
3340 i[3456]86-sequent-sysv*
3341 i[3456]86-sequent-bsd*
3342 Tsqware Sparclet sparclet-*-*
3343 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3345 * REMOVED configurations and files
3348 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3349 IBM AIX PS/2 i[3456]86-*-aix
3350 i386 running Mach 3.0 i[3456]86-*-mach3*
3351 i386 running Mach i[3456]86-*-mach*
3352 i386 running OSF/1 i[3456]86-*osf1mk*
3353 HP/Apollo 68k Family m68*-apollo*-sysv*,
3355 m68*-hp-bsd*, m68*-hp-hpux*
3356 Argonaut Risc Chip (ARC) arc-*-*
3357 Mitsubishi D30V d30v-*-*
3358 Fujitsu FR30 fr30-*-elf*
3359 OS/9000 i[34]86-*-os9k
3360 I960 with MON960 i960-*-coff
3362 * MIPS $fp behavior changed
3364 The convenience variable $fp, for the MIPS, now consistently returns
3365 the address of the current frame's base. Previously, depending on the
3366 context, $fp could refer to either $sp or the current frame's base
3367 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3368 The GNU Source-Level Debugger''.
3370 *** Changes in GDB 5.3:
3372 * GNU/Linux shared library multi-threaded performance improved.
3374 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3375 `/proc', in preference to `ptrace' for memory reads. This may result
3376 in an improvement in the start-up time of multi-threaded, shared
3377 library applications when run under GDB. One GDB user writes: ``loads
3378 shared libs like mad''.
3380 * ``gdbserver'' now supports multi-threaded applications on some targets
3382 Support for debugging multi-threaded applications which use
3383 the GNU/Linux LinuxThreads package has been added for
3384 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3385 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3387 * GDB now supports C/C++ preprocessor macros.
3389 GDB now expands preprocessor macro invocations in C/C++ expressions,
3390 and provides various commands for showing macro definitions and how
3393 The new command `macro expand EXPRESSION' expands any macro
3394 invocations in expression, and shows the result.
3396 The new command `show macro MACRO-NAME' shows the definition of the
3397 macro named MACRO-NAME, and where it was defined.
3399 Most compilers don't include information about macros in the debugging
3400 information by default. In GCC 3.1, for example, you need to compile
3401 your program with the options `-gdwarf-2 -g3'. If the macro
3402 information is present in the executable, GDB will read it.
3404 * Multi-arched targets.
3406 DEC Alpha (partial) alpha*-*-*
3407 DEC VAX (partial) vax-*-*
3409 National Semiconductor NS32000 (partial) ns32k-*-*
3410 Motorola 68000 (partial) m68k-*-*
3411 Motorola MCORE mcore-*-*
3415 Fujitsu FRV architecture added by Red Hat frv*-*-*
3418 * New native configurations
3420 Alpha NetBSD alpha*-*-netbsd*
3421 SH NetBSD sh*-*-netbsdelf*
3422 MIPS NetBSD mips*-*-netbsd*
3423 UltraSPARC NetBSD sparc64-*-netbsd*
3425 * OBSOLETE configurations and files
3427 Configurations that have been declared obsolete in this release have
3428 been commented out. Unless there is activity to revive these
3429 configurations, the next release of GDB will have their sources
3430 permanently REMOVED.
3432 Mitsubishi D30V d30v-*-*
3433 OS/9000 i[34]86-*-os9k
3434 IBM AIX PS/2 i[3456]86-*-aix
3435 Fujitsu FR30 fr30-*-elf*
3436 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3437 Argonaut Risc Chip (ARC) arc-*-*
3438 i386 running Mach 3.0 i[3456]86-*-mach3*
3439 i386 running Mach i[3456]86-*-mach*
3440 i386 running OSF/1 i[3456]86-*osf1mk*
3441 HP/Apollo 68k Family m68*-apollo*-sysv*,
3443 m68*-hp-bsd*, m68*-hp-hpux*
3444 I960 with MON960 i960-*-coff
3446 * OBSOLETE languages
3448 CHILL, a Pascal like language used by telecommunications companies.
3450 * REMOVED configurations and files
3452 AMD 29k family via UDI a29k-amd-udi, udi29k
3453 A29K VxWorks a29k-*-vxworks
3454 AMD 29000 embedded, using EBMON a29k-none-none
3455 AMD 29000 embedded with COFF a29k-none-coff
3456 AMD 29000 embedded with a.out a29k-none-aout
3458 testsuite/gdb.hp/gdb.threads-hp/ directory
3460 * New command "set max-user-call-depth <nnn>"
3462 This command allows the user to limit the call depth of user-defined
3463 commands. The default is 1024.
3465 * Changes in FreeBSD/i386 native debugging.
3467 Support for the "generate-core-file" has been added.
3469 * New commands "dump", "append", and "restore".
3471 These commands allow data to be copied from target memory
3472 to a bfd-format or binary file (dump and append), and back
3473 from a file into memory (restore).
3475 * Improved "next/step" support on multi-processor Alpha Tru64.
3477 The previous single-step mechanism could cause unpredictable problems,
3478 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3479 of a software single-step mechanism prevents this.
3481 *** Changes in GDB 5.2.1:
3489 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3490 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3491 Fix, by Joel Brobecker imported from mainline.
3493 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3494 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3495 Fix, by Fred Fish, imported from mainline.
3497 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3498 Surprisingly enough, it works now.
3499 By Michal Ludvig, imported from mainline.
3501 i386 hardware watchpoint support:
3502 avoid misses on second run for some targets.
3503 By Pierre Muller, imported from mainline.
3505 *** Changes in GDB 5.2:
3507 * New command "set trust-readonly-sections on[off]".
3509 This command is a hint that tells gdb that read-only sections
3510 really are read-only (ie. that their contents will not change).
3511 In this mode, gdb will go to the object file rather than the
3512 target to read memory from read-only sections (such as ".text").
3513 This can be a significant performance improvement on some
3514 (notably embedded) targets.
3516 * New command "generate-core-file" (or "gcore").
3518 This new gdb command allows the user to drop a core file of the child
3519 process state at any time. So far it's been implemented only for
3520 GNU/Linux and Solaris, but should be relatively easily ported to other
3521 hosts. Argument is core file name (defaults to core.<pid>).
3523 * New command line option
3525 GDB now accepts --pid or -p followed by a process id.
3527 * Change in command line behavior -- corefiles vs. process ids.
3529 There is a subtle behavior in the way in which GDB handles
3530 command line arguments. The first non-flag argument is always
3531 a program to debug, but the second non-flag argument may either
3532 be a corefile or a process id. Previously, GDB would attempt to
3533 open the second argument as a corefile, and if that failed, would
3534 issue a superfluous error message and then attempt to attach it as
3535 a process. Now, if the second argument begins with a non-digit,
3536 it will be treated as a corefile. If it begins with a digit,
3537 GDB will attempt to attach it as a process, and if no such process
3538 is found, will then attempt to open it as a corefile.
3540 * Changes in ARM configurations.
3542 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3543 configuration is fully multi-arch.
3545 * New native configurations
3547 ARM NetBSD arm*-*-netbsd*
3548 x86 OpenBSD i[3456]86-*-openbsd*
3549 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3550 Sparc64 running FreeBSD sparc64-*-freebsd*
3554 Sanyo XStormy16 xstormy16-elf
3556 * OBSOLETE configurations and files
3558 Configurations that have been declared obsolete in this release have
3559 been commented out. Unless there is activity to revive these
3560 configurations, the next release of GDB will have their sources
3561 permanently REMOVED.
3563 AMD 29k family via UDI a29k-amd-udi, udi29k
3564 A29K VxWorks a29k-*-vxworks
3565 AMD 29000 embedded, using EBMON a29k-none-none
3566 AMD 29000 embedded with COFF a29k-none-coff
3567 AMD 29000 embedded with a.out a29k-none-aout
3569 testsuite/gdb.hp/gdb.threads-hp/ directory
3571 * REMOVED configurations and files
3573 TI TMS320C80 tic80-*-*
3575 PowerPC Solaris powerpcle-*-solaris*
3576 PowerPC Windows NT powerpcle-*-cygwin32
3577 PowerPC Netware powerpc-*-netware*
3578 Harris/CXUX m88k m88*-harris-cxux*
3579 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3580 ns32k-utek-sysv* ns32k-utek-*
3581 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3582 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3583 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3584 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3585 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3587 * Changes to command line processing
3589 The new `--args' feature can be used to specify command-line arguments
3590 for the inferior from gdb's command line.
3592 * Changes to key bindings
3594 There is a new `operate-and-get-next' function bound to `C-o'.
3596 *** Changes in GDB 5.1.1
3598 Fix compile problem on DJGPP.
3600 Fix a problem with floating-point registers on the i386 being
3603 Fix to stop GDB crashing on .debug_str debug info.
3605 Numerous documentation fixes.
3607 Numerous testsuite fixes.
3609 *** Changes in GDB 5.1:
3611 * New native configurations
3613 Alpha FreeBSD alpha*-*-freebsd*
3614 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3615 MIPS GNU/Linux mips*-*-linux*
3616 MIPS SGI Irix 6.x mips*-sgi-irix6*
3617 ia64 AIX ia64-*-aix*
3618 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3622 Motorola 68HC11 and 68HC12 m68hc11-elf
3624 UltraSparc running GNU/Linux sparc64-*-linux*
3626 * OBSOLETE configurations and files
3628 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3629 Harris/CXUX m88k m88*-harris-cxux*
3630 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3631 ns32k-utek-sysv* ns32k-utek-*
3632 TI TMS320C80 tic80-*-*
3634 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3635 PowerPC Solaris powerpcle-*-solaris*
3636 PowerPC Windows NT powerpcle-*-cygwin32
3637 PowerPC Netware powerpc-*-netware*
3638 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3639 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3640 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3641 Apple Macintosh (MPW) host N/A
3643 stuff.c (Program to stuff files into a specially prepared space in kdb)
3644 kdb-start.c (Main loop for the standalone kernel debugger)
3646 Configurations that have been declared obsolete in this release have
3647 been commented out. Unless there is activity to revive these
3648 configurations, the next release of GDB will have their sources
3649 permanently REMOVED.
3651 * REMOVED configurations and files
3653 Altos 3068 m68*-altos-*
3654 Convex c1-*-*, c2-*-*
3656 ARM RISCix arm-*-* (as host)
3660 * GDB has been converted to ISO C.
3662 GDB's source code has been converted to ISO C. In particular, the
3663 sources are fully protoized, and rely on standard headers being
3668 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3670 * The MI enabled by default.
3672 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3673 revised and enabled by default. Packages which use GDB as a debugging
3674 engine behind a UI or another front end are encouraged to switch to
3675 using the GDB/MI interface, instead of the old annotations interface
3676 which is now deprecated.
3678 * Support for debugging Pascal programs.
3680 GDB now includes support for debugging Pascal programs. The following
3681 main features are supported:
3683 - Pascal-specific data types such as sets;
3685 - automatic recognition of Pascal sources based on file-name
3688 - Pascal-style display of data types, variables, and functions;
3690 - a Pascal expression parser.
3692 However, some important features are not yet supported.
3694 - Pascal string operations are not supported at all;
3696 - there are some problems with boolean types;
3698 - Pascal type hexadecimal constants are not supported
3699 because they conflict with the internal variables format;
3701 - support for Pascal objects and classes is not full yet;
3703 - unlike Pascal, GDB is case-sensitive for symbol names.
3705 * Changes in completion.
3707 Commands such as `shell', `run' and `set args', which pass arguments
3708 to inferior programs, now complete on file names, similar to what
3709 users expect at the shell prompt.
3711 Commands which accept locations, such as `disassemble', `print',
3712 `breakpoint', `until', etc. now complete on filenames as well as
3713 program symbols. Thus, if you type "break foob TAB", and the source
3714 files linked into the programs include `foobar.c', that file name will
3715 be one of the candidates for completion. However, file names are not
3716 considered for completion after you typed a colon that delimits a file
3717 name from a name of a function in that file, as in "break foo.c:bar".
3719 `set demangle-style' completes on available demangling styles.
3721 * New platform-independent commands:
3723 It is now possible to define a post-hook for a command as well as a
3724 hook that runs before the command. For more details, see the
3725 documentation of `hookpost' in the GDB manual.
3727 * Changes in GNU/Linux native debugging.
3729 Support for debugging multi-threaded programs has been completely
3730 revised for all platforms except m68k and sparc. You can now debug as
3731 many threads as your system allows you to have.
3733 Attach/detach is supported for multi-threaded programs.
3735 Support for SSE registers was added for x86. This doesn't work for
3736 multi-threaded programs though.
3738 * Changes in MIPS configurations.
3740 Multi-arch support is enabled for all MIPS configurations.
3742 GDB can now be built as native debugger on SGI Irix 6.x systems for
3743 debugging n32 executables. (Debugging 64-bit executables is not yet
3746 * Unified support for hardware watchpoints in all x86 configurations.
3748 Most (if not all) native x86 configurations support hardware-assisted
3749 breakpoints and watchpoints in a unified manner. This support
3750 implements debug register sharing between watchpoints, which allows to
3751 put a virtually infinite number of watchpoints on the same address,
3752 and also supports watching regions up to 16 bytes with several debug
3755 The new maintenance command `maintenance show-debug-regs' toggles
3756 debugging print-outs in functions that insert, remove, and test
3757 watchpoints and hardware breakpoints.
3759 * Changes in the DJGPP native configuration.
3761 New command ``info dos sysinfo'' displays assorted information about
3762 the CPU, OS, memory, and DPMI server.
3764 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3765 display information about segment descriptors stored in GDT, LDT, and
3768 New commands ``info dos pde'' and ``info dos pte'' display entries
3769 from Page Directory and Page Tables (for now works with CWSDPMI only).
3770 New command ``info dos address-pte'' displays the Page Table entry for
3771 a given linear address.
3773 GDB can now pass command lines longer than 126 characters to the
3774 program being debugged (requires an update to the libdbg.a library
3775 which is part of the DJGPP development kit).
3777 DWARF2 debug info is now supported.
3779 It is now possible to `step' and `next' through calls to `longjmp'.
3781 * Changes in documentation.
3783 All GDB documentation was converted to GFDL, the GNU Free
3784 Documentation License.
3786 Tracepoints-related commands are now fully documented in the GDB
3789 TUI, the Text-mode User Interface, is now documented in the manual.
3791 Tracepoints-related commands are now fully documented in the GDB
3794 The "GDB Internals" manual now has an index. It also includes
3795 documentation of `ui_out' functions, GDB coding standards, x86
3796 hardware watchpoints, and memory region attributes.
3798 * GDB's version number moved to ``version.in''
3800 The Makefile variable VERSION has been replaced by the file
3801 ``version.in''. People creating GDB distributions should update the
3802 contents of this file.
3806 GUD support is now a standard part of the EMACS distribution.
3808 *** Changes in GDB 5.0:
3810 * Improved support for debugging FP programs on x86 targets
3812 Unified and much-improved support for debugging floating-point
3813 programs on all x86 targets. In particular, ``info float'' now
3814 displays the FP registers in the same format on all x86 targets, with
3815 greater level of detail.
3817 * Improvements and bugfixes in hardware-assisted watchpoints
3819 It is now possible to watch array elements, struct members, and
3820 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3821 on x86 targets no longer erroneously trigger when the address is
3824 * Improvements in the native DJGPP version of GDB
3826 The distribution now includes all the scripts and auxiliary files
3827 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3828 machines ``out of the box''.
3830 The DJGPP version can now debug programs that use signals. It is
3831 possible to catch signals that happened in the debuggee, deliver
3832 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3833 would kill the program being debugged.) Programs that hook hardware
3834 interrupts (keyboard, timer, etc.) can also be debugged.
3836 It is now possible to debug DJGPP programs that redirect their
3837 standard handles or switch them to raw (as opposed to cooked) mode, or
3838 even close them. The command ``run < foo > bar'' works as expected,
3839 and ``info terminal'' reports useful information about the debuggee's
3840 terminal, including raw/cooked mode, redirection, etc.
3842 The DJGPP version now uses termios functions for console I/O, which
3843 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3846 DOS-style file names with drive letters are now fully supported by
3849 It is now possible to debug DJGPP programs that switch their working
3850 directory. It is also possible to rerun the debuggee any number of
3851 times without restarting GDB; thus, you can use the same setup,
3852 breakpoints, etc. for many debugging sessions.
3854 * New native configurations
3856 ARM GNU/Linux arm*-*-linux*
3857 PowerPC GNU/Linux powerpc-*-linux*
3861 Motorola MCore mcore-*-*
3862 x86 VxWorks i[3456]86-*-vxworks*
3863 PowerPC VxWorks powerpc-*-vxworks*
3864 TI TMS320C80 tic80-*-*
3866 * OBSOLETE configurations
3868 Altos 3068 m68*-altos-*
3869 Convex c1-*-*, c2-*-*
3871 ARM RISCix arm-*-* (as host)
3874 Configurations that have been declared obsolete will be commented out,
3875 but the code will be left in place. If there is no activity to revive
3876 these configurations before the next release of GDB, the sources will
3877 be permanently REMOVED.
3879 * Gould support removed
3881 Support for the Gould PowerNode and NP1 has been removed.
3883 * New features for SVR4
3885 On SVR4 native platforms (such as Solaris), if you attach to a process
3886 without first loading a symbol file, GDB will now attempt to locate and
3887 load symbols from the running process's executable file.
3889 * Many C++ enhancements
3891 C++ support has been greatly improved. Overload resolution now works properly
3892 in almost all cases. RTTI support is on the way.
3894 * Remote targets can connect to a sub-program
3896 A popen(3) style serial-device has been added. This device starts a
3897 sub-process (such as a stand-alone simulator) and then communicates
3898 with that. The sub-program to run is specified using the syntax
3899 ``|<program> <args>'' vis:
3901 (gdb) set remotedebug 1
3902 (gdb) target extended-remote |mn10300-elf-sim program-args
3904 * MIPS 64 remote protocol
3906 A long standing bug in the mips64 remote protocol where by GDB
3907 expected certain 32 bit registers (ex SR) to be transfered as 32
3908 instead of 64 bits has been fixed.
3910 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3911 added to provide backward compatibility with older versions of GDB.
3913 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3915 The command ``set remotebinarydownload'' command has been replaced by
3916 ``set remote X-packet''. Other commands in ``set remote'' family
3917 include ``set remote P-packet''.
3919 * Breakpoint commands accept ranges.
3921 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3922 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3923 ``tracepoint passcount'' also accepts a range of tracepoints.
3925 * ``apropos'' command added.
3927 The ``apropos'' command searches through command names and
3928 documentation strings, printing out matches, making it much easier to
3929 try to find a command that does what you are looking for.
3933 A new machine oriented interface (MI) has been added to GDB. This
3934 interface is designed for debug environments running GDB as a separate
3935 process. This is part of the long term libGDB project. See the
3936 "GDB/MI" chapter of the GDB manual for further information. It can be
3937 enabled by configuring with:
3939 .../configure --enable-gdbmi
3941 *** Changes in GDB-4.18:
3943 * New native configurations
3945 HP-UX 10.20 hppa*-*-hpux10.20
3946 HP-UX 11.x hppa*-*-hpux11.0*
3947 M68K GNU/Linux m68*-*-linux*
3951 Fujitsu FR30 fr30-*-elf*
3952 Intel StrongARM strongarm-*-*
3953 Mitsubishi D30V d30v-*-*
3955 * OBSOLETE configurations
3957 Gould PowerNode, NP1 np1-*-*, pn-*-*
3959 Configurations that have been declared obsolete will be commented out,
3960 but the code will be left in place. If there is no activity to revive
3961 these configurations before the next release of GDB, the sources will
3962 be permanently REMOVED.
3966 As a compatibility experiment, GDB's source files buildsym.h and
3967 buildsym.c have been converted to pure standard C, no longer
3968 containing any K&R compatibility code. We believe that all systems in
3969 use today either come with a standard C compiler, or have a GCC port
3970 available. If this is not true, please report the affected
3971 configuration to bug-gdb@gnu.org immediately. See the README file for
3972 information about getting a standard C compiler if you don't have one
3977 GDB now uses readline 2.2.
3979 * set extension-language
3981 You can now control the mapping between filename extensions and source
3982 languages by using the `set extension-language' command. For instance,
3983 you can ask GDB to treat .c files as C++ by saying
3984 set extension-language .c c++
3985 The command `info extensions' lists all of the recognized extensions
3986 and their associated languages.
3988 * Setting processor type for PowerPC and RS/6000
3990 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3991 you can use the `set processor' command to specify what variant of the
3992 PowerPC family you are debugging. The command
3996 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3997 following PowerPC and RS6000 variants:
3999 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4000 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4002 403GC IBM PowerPC 403GC
4003 505 Motorola PowerPC 505
4004 860 Motorola PowerPC 860 or 850
4005 601 Motorola PowerPC 601
4006 602 Motorola PowerPC 602
4007 603 Motorola/IBM PowerPC 603 or 603e
4008 604 Motorola PowerPC 604 or 604e
4009 750 Motorola/IBM PowerPC 750 or 750
4011 At the moment, this command just tells GDB what to name the
4012 special-purpose processor registers. Since almost all the affected
4013 registers are inaccessible to user-level programs, this command is
4014 only useful for remote debugging in its present form.
4018 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4019 more extensive support for HP-UX. Added features include shared
4020 library support, kernel threads and hardware watchpoints for 11.00,
4021 support for HP's ANSI C and C++ compilers, and a compatibility mode
4022 for xdb and dbx commands.
4026 HP's donation includes the new concept of catchpoints, which is a
4027 generalization of the old catch command. On HP-UX, it is now possible
4028 to catch exec, fork, and vfork, as well as library loading.
4030 This means that the existing catch command has changed; its first
4031 argument now specifies the type of catch to be set up. See the
4032 output of "help catch" for a list of catchpoint types.
4034 * Debugging across forks
4036 On HP-UX, you can choose which process to debug when a fork() happens
4041 HP has donated a curses-based terminal user interface (TUI). To get
4042 it, build with --enable-tui. Although this can be enabled for any
4043 configuration, at present it only works for native HP debugging.
4045 * GDB remote protocol additions
4047 A new protocol packet 'X' that writes binary data is now available.
4048 Default behavior is to try 'X', then drop back to 'M' if the stub
4049 fails to respond. The settable variable `remotebinarydownload'
4050 allows explicit control over the use of 'X'.
4052 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4053 full 64-bit address. The command
4055 set remoteaddresssize 32
4057 can be used to revert to the old behaviour. For existing remote stubs
4058 the change should not be noticed, as the additional address information
4061 In order to assist in debugging stubs, you may use the maintenance
4062 command `packet' to send any text string to the stub. For instance,
4064 maint packet heythere
4066 sends the packet "$heythere#<checksum>". Note that it is very easy to
4067 disrupt a debugging session by sending the wrong packet at the wrong
4070 The compare-sections command allows you to compare section data on the
4071 target to what is in the executable file without uploading or
4072 downloading, by comparing CRC checksums.
4074 * Tracing can collect general expressions
4076 You may now collect general expressions at tracepoints. This requires
4077 further additions to the target-side stub; see tracepoint.c and
4078 doc/agentexpr.texi for further details.
4080 * mask-address variable for Mips
4082 For Mips targets, you may control the zeroing of the upper 32 bits of
4083 a 64-bit address by entering `set mask-address on'. This is mainly
4084 of interest to users of embedded R4xxx and R5xxx processors.
4086 * Higher serial baud rates
4088 GDB's serial code now allows you to specify baud rates 57600, 115200,
4089 230400, and 460800 baud. (Note that your host system may not be able
4090 to achieve all of these rates.)
4094 The i960 configuration now includes an initial implementation of a
4095 builtin simulator, contributed by Jim Wilson.
4098 *** Changes in GDB-4.17:
4100 * New native configurations
4102 Alpha GNU/Linux alpha*-*-linux*
4103 Unixware 2.x i[3456]86-unixware2*
4104 Irix 6.x mips*-sgi-irix6*
4105 PowerPC GNU/Linux powerpc-*-linux*
4106 PowerPC Solaris powerpcle-*-solaris*
4107 Sparc GNU/Linux sparc-*-linux*
4108 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4112 Argonaut Risc Chip (ARC) arc-*-*
4113 Hitachi H8/300S h8300*-*-*
4114 Matsushita MN10200 w/simulator mn10200-*-*
4115 Matsushita MN10300 w/simulator mn10300-*-*
4116 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4117 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4118 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4119 Mitsubishi D10V w/simulator d10v-*-*
4120 Mitsubishi M32R/D w/simulator m32r-*-elf*
4121 Tsqware Sparclet sparclet-*-*
4122 NEC V850 w/simulator v850-*-*
4124 * New debugging protocols
4126 ARM with RDI protocol arm*-*-*
4127 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4128 DDB and LSI variants of PMON protocol mips*-*-*
4129 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4130 PowerPC with SDS protocol powerpc{,le}-*-eabi
4131 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4135 All configurations can now understand and use the DWARF 2 debugging
4136 format. The choice is automatic, if the symbol file contains DWARF 2
4141 GDB now includes basic Java language support. This support is
4142 only useful with Java compilers that produce native machine code.
4144 * solib-absolute-prefix and solib-search-path
4146 For SunOS and SVR4 shared libraries, you may now set the prefix for
4147 loading absolute shared library symbol files, and the search path for
4148 locating non-absolute shared library symbol files.
4150 * Live range splitting
4152 GDB can now effectively debug code for which GCC has performed live
4153 range splitting as part of its optimization. See gdb/doc/LRS for
4154 more details on the expected format of the stabs information.
4158 GDB's support for the GNU Hurd, including thread debugging, has been
4159 updated to work with current versions of the Hurd.
4163 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4164 instruction set. ARM GDB automatically detects when Thumb
4165 instructions are in use, and adjusts disassembly and backtracing
4170 GDB's MIPS target configurations now handle the MIP16 16-bit
4175 GDB now includes support for overlays; if an executable has been
4176 linked such that multiple sections are based at the same address, GDB
4177 will decide which section to use for symbolic info. You can choose to
4178 control the decision manually, using overlay commands, or implement
4179 additional target-side support and use "overlay load-target" to bring
4180 in the overlay mapping. Do "help overlay" for more detail.
4184 The command "info symbol <address>" displays information about
4185 the symbol at the specified address.
4189 The standard remote protocol now includes an extension that allows
4190 asynchronous collection and display of trace data. This requires
4191 extensive support in the target-side debugging stub. Tracing mode
4192 includes a new interaction mode in GDB and new commands: see the
4193 file tracepoint.c for more details.
4197 Configurations for embedded MIPS now include a simulator contributed
4198 by Cygnus Solutions. The simulator supports the instruction sets
4199 of most MIPS variants.
4203 Sparc configurations may now include the ERC32 simulator contributed
4204 by the European Space Agency. The simulator is not built into
4205 Sparc targets by default; configure with --enable-sim to include it.
4209 For target configurations that may include multiple variants of a
4210 basic architecture (such as MIPS and SH), you may now set the
4211 architecture explicitly. "set arch" sets, "info arch" lists
4212 the possible architectures.
4214 *** Changes in GDB-4.16:
4216 * New native configurations
4218 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4219 M68K NetBSD m68k-*-netbsd*
4220 PowerPC AIX 4.x powerpc-*-aix*
4221 PowerPC MacOS powerpc-*-macos*
4222 PowerPC Windows NT powerpcle-*-cygwin32
4223 RS/6000 AIX 4.x rs6000-*-aix4*
4227 ARM with RDP protocol arm-*-*
4228 I960 with MON960 i960-*-coff
4229 MIPS VxWorks mips*-*-vxworks*
4230 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4231 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4233 Matra Sparclet sparclet-*-*
4237 The powerpc-eabi configuration now includes the PSIM simulator,
4238 contributed by Andrew Cagney, with assistance from Mike Meissner.
4239 PSIM is a very elaborate model of the PowerPC, including not only
4240 basic instruction set execution, but also details of execution unit
4241 performance and I/O hardware. See sim/ppc/README for more details.
4245 GDB now works with Solaris 2.5.
4247 * Windows 95/NT native
4249 GDB will now work as a native debugger on Windows 95 and Windows NT.
4250 To build it from source, you must use the "gnu-win32" environment,
4251 which uses a DLL to emulate enough of Unix to run the GNU tools.
4252 Further information, binaries, and sources are available at
4253 ftp.cygnus.com, under pub/gnu-win32.
4255 * dont-repeat command
4257 If a user-defined command includes the command `dont-repeat', then the
4258 command will not be repeated if the user just types return. This is
4259 useful if the command is time-consuming to run, so that accidental
4260 extra keystrokes don't run the same command many times.
4262 * Send break instead of ^C
4264 The standard remote protocol now includes an option to send a break
4265 rather than a ^C to the target in order to interrupt it. By default,
4266 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4268 * Remote protocol timeout
4270 The standard remote protocol includes a new variable `remotetimeout'
4271 that allows you to set the number of seconds before GDB gives up trying
4272 to read from the target. The default value is 2.
4274 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4276 By default GDB will automatically keep track of objects as they are
4277 loaded and unloaded by the dynamic linker. By using the command `set
4278 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4279 when shared library events occur, thus allowing you to set breakpoints
4280 in shared libraries which are explicitly loaded by the inferior.
4282 Note this feature does not work on hpux8. On hpux9 you must link
4283 /usr/lib/end.o into your program. This feature should work
4284 automatically on hpux10.
4286 * Irix 5.x hardware watchpoint support
4288 Irix 5 configurations now support the use of hardware watchpoints.
4290 * Mips protocol "SYN garbage limit"
4292 When debugging a Mips target using the `target mips' protocol, you
4293 may set the number of characters that GDB will ignore by setting
4294 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4295 every character. The default value is 1050.
4297 * Recording and replaying remote debug sessions
4299 If you set `remotelogfile' to the name of a file, gdb will write to it
4300 a recording of a remote debug session. This recording may then be
4301 replayed back to gdb using "gdbreplay". See gdbserver/README for
4302 details. This is useful when you have a problem with GDB while doing
4303 remote debugging; you can make a recording of the session and send it
4304 to someone else, who can then recreate the problem.
4306 * Speedups for remote debugging
4308 GDB includes speedups for downloading and stepping MIPS systems using
4309 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4310 and more efficient S-record downloading.
4312 * Memory use reductions and statistics collection
4314 GDB now uses less memory and reports statistics about memory usage.
4315 Try the `maint print statistics' command, for example.
4317 *** Changes in GDB-4.15:
4319 * Psymtabs for XCOFF
4321 The symbol reader for AIX GDB now uses partial symbol tables. This
4322 can greatly improve startup time, especially for large executables.
4324 * Remote targets use caching
4326 Remote targets now use a data cache to speed up communication with the
4327 remote side. The data cache could lead to incorrect results because
4328 it doesn't know about volatile variables, thus making it impossible to
4329 debug targets which use memory mapped I/O devices. `set remotecache
4330 off' turns the the data cache off.
4332 * Remote targets may have threads
4334 The standard remote protocol now includes support for multiple threads
4335 in the target system, using new protocol commands 'H' and 'T'. See
4336 gdb/remote.c for details.
4340 If GDB is configured with `--enable-netrom', then it will include
4341 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4342 acts as though it is a bank of ROM on the target board, but you can
4343 write into it over the network. GDB's support consists only of
4344 support for fast loading into the emulated ROM; to debug, you must use
4345 another protocol, such as standard remote protocol. The usual
4346 sequence is something like
4348 target nrom <netrom-hostname>
4350 target remote <netrom-hostname>:1235
4354 GDB now includes support for the Apple Macintosh, as a host only. It
4355 may be run as either an MPW tool or as a standalone application, and
4356 it can debug through the serial port. All the usual GDB commands are
4357 available, but to the target command, you must supply "serial" as the
4358 device type instead of "/dev/ttyXX". See mpw-README in the main
4359 directory for more information on how to build. The MPW configuration
4360 scripts */mpw-config.in support only a few targets, and only the
4361 mips-idt-ecoff target has been tested.
4365 GDB configuration now uses autoconf. This is not user-visible,
4366 but does simplify configuration and building.
4370 GDB now supports hpux10.
4372 *** Changes in GDB-4.14:
4374 * New native configurations
4376 x86 FreeBSD i[345]86-*-freebsd
4377 x86 NetBSD i[345]86-*-netbsd
4378 NS32k NetBSD ns32k-*-netbsd
4379 Sparc NetBSD sparc-*-netbsd
4383 A29K VxWorks a29k-*-vxworks
4384 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4385 CPU32 EST-300 emulator m68*-*-est*
4386 PowerPC ELF powerpc-*-elf
4389 * Alpha OSF/1 support for procfs
4391 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4392 possible to attach to running processes. As the mounting of the /proc
4393 filesystem is optional on the Alpha, GDB automatically determines
4394 the availability of /proc during startup. This can lead to problems
4395 if /proc is unmounted after GDB has been started.
4397 * Arguments to user-defined commands
4399 User commands may accept up to 10 arguments separated by whitespace.
4400 Arguments are accessed within the user command via $arg0..$arg9. A
4403 print $arg0 + $arg1 + $arg2
4405 To execute the command use:
4408 Defines the command "adder" which prints the sum of its three arguments.
4409 Note the arguments are text substitutions, so they may reference variables,
4410 use complex expressions, or even perform inferior function calls.
4412 * New `if' and `while' commands
4414 This makes it possible to write more sophisticated user-defined
4415 commands. Both commands take a single argument, which is the
4416 expression to evaluate, and must be followed by the commands to
4417 execute, one per line, if the expression is nonzero, the list being
4418 terminated by the word `end'. The `if' command list may include an
4419 `else' word, which causes the following commands to be executed only
4420 if the expression is zero.
4422 * Fortran source language mode
4424 GDB now includes partial support for Fortran 77. It will recognize
4425 Fortran programs and can evaluate a subset of Fortran expressions, but
4426 variables and functions may not be handled correctly. GDB will work
4427 with G77, but does not yet know much about symbols emitted by other
4430 * Better HPUX support
4432 Most debugging facilities now work on dynamic executables for HPPAs
4433 running hpux9 or later. You can attach to running dynamically linked
4434 processes, but by default the dynamic libraries will be read-only, so
4435 for instance you won't be able to put breakpoints in them. To change
4436 that behavior do the following before running the program:
4442 This will cause the libraries to be mapped private and read-write.
4443 To revert to the normal behavior, do this:
4449 You cannot set breakpoints or examine data in the library until after
4450 the library is loaded if the function/data symbols do not have
4453 GDB can now also read debug symbols produced by the HP C compiler on
4454 HPPAs (sorry, no C++, Fortran or 68k support).
4456 * Target byte order now dynamically selectable
4458 You can choose which byte order to use with a target system, via the
4459 commands "set endian big" and "set endian little", and you can see the
4460 current setting by using "show endian". You can also give the command
4461 "set endian auto", in which case GDB will use the byte order
4462 associated with the executable. Currently, only embedded MIPS
4463 configurations support dynamic selection of target byte order.
4465 * New DOS host serial code
4467 This version uses DPMI interrupts to handle buffered I/O, so you
4468 no longer need to run asynctsr when debugging boards connected to
4471 *** Changes in GDB-4.13:
4473 * New "complete" command
4475 This lists all the possible completions for the rest of the line, if it
4476 were to be given as a command itself. This is intended for use by emacs.
4478 * Trailing space optional in prompt
4480 "set prompt" no longer adds a space for you after the prompt you set. This
4481 allows you to set a prompt which ends in a space or one that does not.
4483 * Breakpoint hit counts
4485 "info break" now displays a count of the number of times the breakpoint
4486 has been hit. This is especially useful in conjunction with "ignore"; you
4487 can ignore a large number of breakpoint hits, look at the breakpoint info
4488 to see how many times the breakpoint was hit, then run again, ignoring one
4489 less than that number, and this will get you quickly to the last hit of
4492 * Ability to stop printing at NULL character
4494 "set print null-stop" will cause GDB to stop printing the characters of
4495 an array when the first NULL is encountered. This is useful when large
4496 arrays actually contain only short strings.
4498 * Shared library breakpoints
4500 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4501 breakpoints in shared libraries before the executable is run.
4503 * Hardware watchpoints
4505 There is a new hardware breakpoint for the watch command for sparclite
4506 targets. See gdb/sparclite/hw_breakpoint.note.
4508 Hardware watchpoints are also now supported under GNU/Linux.
4512 Annotations have been added. These are for use with graphical interfaces,
4513 and are still experimental. Currently only gdba.el uses these.
4515 * Improved Irix 5 support
4517 GDB now works properly with Irix 5.2.
4519 * Improved HPPA support
4521 GDB now works properly with the latest GCC and GAS.
4523 * New native configurations
4525 Sequent PTX4 i[34]86-sequent-ptx4
4526 HPPA running OSF/1 hppa*-*-osf*
4527 Atari TT running SVR4 m68*-*-sysv4*
4528 RS/6000 LynxOS rs6000-*-lynxos*
4532 OS/9000 i[34]86-*-os9k
4533 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4536 * Hitachi SH7000 and E7000-PC ICE support
4538 There is now support for communicating with the Hitachi E7000-PC ICE.
4539 This is available automatically when GDB is configured for the SH.
4543 As usual, a variety of small fixes and improvements, both generic
4544 and configuration-specific. See the ChangeLog for more detail.
4546 *** Changes in GDB-4.12:
4548 * Irix 5 is now supported
4552 GDB-4.12 on the HPPA has a number of changes which make it unable
4553 to debug the output from the currently released versions of GCC and
4554 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4555 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4556 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4559 *** Changes in GDB-4.11:
4561 * User visible changes:
4565 The "set remotedebug" option is now consistent between the mips remote
4566 target, remote targets using the gdb-specific protocol, UDI (AMD's
4567 debug protocol for the 29k) and the 88k bug monitor. It is now an
4568 integer specifying a debug level (normally 0 or 1, but 2 means more
4569 debugging info for the mips target).
4571 * DEC Alpha native support
4573 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4574 debug info, but GDB works fairly well with the DEC compiler and should
4575 work with a future GCC release. See the README file for a few
4576 Alpha-specific notes.
4578 * Preliminary thread implementation
4580 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4582 * LynxOS native and target support for 386
4584 This release has been hosted on LynxOS 2.2, and also can be configured
4585 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4588 * Improvements in C++ mangling/demangling.
4590 This release has much better g++ debugging, specifically in name
4591 mangling/demangling, virtual function calls, print virtual table,
4592 call methods, ...etc.
4594 *** Changes in GDB-4.10:
4596 * User visible changes:
4598 Remote debugging using the GDB-specific (`target remote') protocol now
4599 supports the `load' command. This is only useful if you have some
4600 other way of getting the stub to the target system, and you can put it
4601 somewhere in memory where it won't get clobbered by the download.
4603 Filename completion now works.
4605 When run under emacs mode, the "info line" command now causes the
4606 arrow to point to the line specified. Also, "info line" prints
4607 addresses in symbolic form (as well as hex).
4609 All vxworks based targets now support a user settable option, called
4610 vxworks-timeout. This option represents the number of seconds gdb
4611 should wait for responses to rpc's. You might want to use this if
4612 your vxworks target is, perhaps, a slow software simulator or happens
4613 to be on the far side of a thin network line.
4617 This release contains support for using a DEC alpha as a GDB host for
4618 cross debugging. Native alpha debugging is not supported yet.
4621 *** Changes in GDB-4.9:
4625 This is the first GDB release which is accompanied by a matching testsuite.
4626 The testsuite requires installation of dejagnu, which should be available
4627 via ftp from most sites that carry GNU software.
4631 'Cfront' style demangling has had its name changed to 'ARM' style, to
4632 emphasize that it was written from the specifications in the C++ Annotated
4633 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4634 disclaimers, it still generated too much confusion with users attempting to
4635 use gdb with AT&T cfront.
4639 GDB now uses a standard remote interface to a simulator library.
4640 So far, the library contains simulators for the Zilog Z8001/2, the
4641 Hitachi H8/300, H8/500 and Super-H.
4643 * New targets supported
4645 H8/300 simulator h8300-hitachi-hms or h8300hms
4646 H8/500 simulator h8500-hitachi-hms or h8500hms
4647 SH simulator sh-hitachi-hms or sh
4648 Z8000 simulator z8k-zilog-none or z8ksim
4649 IDT MIPS board over serial line mips-idt-ecoff
4651 Cross-debugging to GO32 targets is supported. It requires a custom
4652 version of the i386-stub.c module which is integrated with the
4653 GO32 memory extender.
4655 * New remote protocols
4657 MIPS remote debugging protocol.
4659 * New source languages supported
4661 This version includes preliminary support for Chill, a Pascal like language
4662 used by telecommunications companies. Chill support is also being integrated
4663 into the GNU compiler, but we don't know when it will be publically available.
4666 *** Changes in GDB-4.8:
4668 * HP Precision Architecture supported
4670 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4671 version of this support was available as a set of patches from the
4672 University of Utah. GDB does not support debugging of programs
4673 compiled with the HP compiler, because HP will not document their file
4674 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4675 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4677 Many problems in the preliminary version have been fixed.
4679 * Faster and better demangling
4681 We have improved template demangling and fixed numerous bugs in the GNU style
4682 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4683 character types (wchar_t) are now supported. Demangling of each symbol is now
4684 only done once, and is cached when the symbol table for a file is read in.
4685 This results in a small increase in memory usage for C programs, a moderate
4686 increase in memory usage for C++ programs, and a fantastic speedup in
4689 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4690 from the specifications in the Annotated Reference Manual, which AT&T's
4691 compiler does not actually implement.
4693 * G++ multiple inheritance compiler problem
4695 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4696 inheritance lattices was reworked to properly discover ambiguities. We
4697 recently found an example which causes this new algorithm to fail in a
4698 very subtle way, producing bad debug information for those classes.
4699 The file 'gcc.patch' (in this directory) can be applied to gcc to
4700 circumvent the problem. A future GCC release will contain a complete
4703 The previous G++ debug info problem (mentioned below for the gdb-4.7
4704 release) is fixed in gcc version 2.3.2.
4706 * Improved configure script
4708 The `configure' script will now attempt to guess your system type if
4709 you don't supply a host system type. The old scheme of supplying a
4710 host system triplet is preferable over using this. All the magic is
4711 done in the new `config.guess' script. Examine it for details.
4713 We have also brought our configure script much more in line with the FSF's
4714 version. It now supports the --with-xxx options. In particular,
4715 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4716 The resulting GDB will not be able to read arbitrary object file formats --
4717 only the format ``expected'' to be used on the configured target system.
4718 We hope to make this the default in a future release.
4720 * Documentation improvements
4722 There's new internal documentation on how to modify GDB, and how to
4723 produce clean changes to the code. We implore people to read it
4724 before submitting changes.
4726 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4727 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4728 `info' files are also provided. To build `info' files from scratch,
4729 you will need the latest `makeinfo' release, which will be available in
4730 a future texinfo-X.Y release.
4732 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4733 We're not sure exactly which versions have this problem, but it has
4734 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4735 or better. If that isn't possible, there is a patch in
4736 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4737 around this problem.
4741 GDB now supports array constants that can be used in expressions typed in by
4742 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4743 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4746 The new directory `gdb/sparclite' contains a program that demonstrates
4747 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4749 * New native hosts supported
4751 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4752 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4754 * New targets supported
4756 AMD 29k family via UDI a29k-amd-udi or udi29k
4758 * New file formats supported
4760 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4761 HPUX core files, and SCO 3.2v2 core files.
4765 Attaching to processes now works again; thanks for the many bug reports.
4767 We have also stomped on a bunch of core dumps caused by
4768 printf_filtered("%s") problems.
4770 We eliminated a copyright problem on the rpc and ptrace header files
4771 for VxWorks, which was discovered at the last minute during the 4.7
4772 release. You should now be able to build a VxWorks GDB.
4774 You can now interrupt gdb while an attached process is running. This
4775 will cause the attached process to stop, and give control back to GDB.
4777 We fixed problems caused by using too many file descriptors
4778 for reading symbols from object files and libraries. This was
4779 especially a problem for programs that used many (~100) shared
4782 The `step' command now only enters a subroutine if there is line number
4783 information for the subroutine. Otherwise it acts like the `next'
4784 command. Previously, `step' would enter subroutines if there was
4785 any debugging information about the routine. This avoids problems
4786 when using `cc -g1' on MIPS machines.
4788 * Internal improvements
4790 GDB's internal interfaces have been improved to make it easier to support
4791 debugging of multiple languages in the future.
4793 GDB now uses a common structure for symbol information internally.
4794 Minimal symbols (derived from linkage symbols in object files), partial
4795 symbols (from a quick scan of debug information), and full symbols
4796 contain a common subset of information, making it easier to write
4797 shared code that handles any of them.
4799 * New command line options
4801 We now accept --silent as an alias for --quiet.
4805 The memory-mapped-malloc library is now licensed under the GNU Library
4806 General Public License.
4808 *** Changes in GDB-4.7:
4810 * Host/native/target split
4812 GDB has had some major internal surgery to untangle the support for
4813 hosts and remote targets. Now, when you configure GDB for a remote
4814 target, it will no longer load in all of the support for debugging
4815 local programs on the host. When fully completed and tested, this will
4816 ensure that arbitrary host/target combinations are possible.
4818 The primary conceptual shift is to separate the non-portable code in
4819 GDB into three categories. Host specific code is required any time GDB
4820 is compiled on that host, regardless of the target. Target specific
4821 code relates to the peculiarities of the target, but can be compiled on
4822 any host. Native specific code is everything else: it can only be
4823 built when the host and target are the same system. Child process
4824 handling and core file support are two common `native' examples.
4826 GDB's use of /proc for controlling Unix child processes is now cleaner.
4827 It has been split out into a single module under the `target_ops' vector,
4828 plus two native-dependent functions for each system that uses /proc.
4830 * New hosts supported
4832 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4833 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4834 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4836 * New targets supported
4838 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4839 68030 and CPU32 m68030-*-*, m68332-*-*
4841 * New native hosts supported
4843 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4844 (386bsd is not well tested yet)
4845 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4847 * New file formats supported
4849 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4850 supports reading of `a.out.adobe' object files, which are an a.out
4851 format extended with minimal information about multiple sections.
4855 `show copying' is the same as the old `info copying'.
4856 `show warranty' is the same as `info warrantee'.
4857 These were renamed for consistency. The old commands continue to work.
4859 `info handle' is a new alias for `info signals'.
4861 You can now define pre-command hooks, which attach arbitrary command
4862 scripts to any command. The commands in the hook will be executed
4863 prior to the user's command. You can also create a hook which will be
4864 executed whenever the program stops. See gdb.texinfo.
4868 We now deal with Cfront style name mangling, and can even extract type
4869 info from mangled symbols. GDB can automatically figure out which
4870 symbol mangling style your C++ compiler uses.
4872 Calling of methods and virtual functions has been improved as well.
4876 The crash that occured when debugging Sun Ansi-C compiled binaries is
4877 fixed. This was due to mishandling of the extra N_SO stabs output
4880 We also finally got Ultrix 4.2 running in house, and fixed core file
4881 support, with help from a dozen people on the net.
4883 John M. Farrell discovered that the reason that single-stepping was so
4884 slow on all of the Mips based platforms (primarily SGI and DEC) was
4885 that we were trying to demangle and lookup a symbol used for internal
4886 purposes on every instruction that was being stepped through. Changing
4887 the name of that symbol so that it couldn't be mistaken for a C++
4888 mangled symbol sped things up a great deal.
4890 Rich Pixley sped up symbol lookups in general by getting much smarter
4891 about when C++ symbol mangling is necessary. This should make symbol
4892 completion (TAB on the command line) much faster. It's not as fast as
4893 we'd like, but it's significantly faster than gdb-4.6.
4897 A new user controllable variable 'call_scratch_address' can
4898 specify the location of a scratch area to be used when GDB
4899 calls a function in the target. This is necessary because the
4900 usual method of putting the scratch area on the stack does not work
4901 in systems that have separate instruction and data spaces.
4903 We integrated changes to support the 29k UDI (Universal Debugger
4904 Interface), but discovered at the last minute that we didn't have all
4905 of the appropriate copyright paperwork. We are working with AMD to
4906 resolve this, and hope to have it available soon.
4910 We have sped up the remote serial line protocol, especially for targets
4911 with lots of registers. It now supports a new `expedited status' ('T')
4912 message which can be used in place of the existing 'S' status message.
4913 This allows the remote stub to send only the registers that GDB
4914 needs to make a quick decision about single-stepping or conditional
4915 breakpoints, eliminating the need to fetch the entire register set for
4916 each instruction being stepped through.
4918 The GDB remote serial protocol now implements a write-through cache for
4919 registers, only re-reading the registers if the target has run.
4921 There is also a new remote serial stub for SPARC processors. You can
4922 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4923 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4924 processor with a serial port.
4928 Configure.in files have become much easier to read and modify. A new
4929 `table driven' format makes it more obvious what configurations are
4930 supported, and what files each one uses.
4934 There is a new opcodes library which will eventually contain all of the
4935 disassembly routines and opcode tables. At present, it only contains
4936 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4937 disassembler (binutils/objdump) to share these routines.
4939 The libiberty library is now copylefted under the GNU Library General
4940 Public License. This allows more liberal use, and was done so libg++
4941 can use it. This makes no difference to GDB, since the Library License
4942 grants all the rights from the General Public License.
4946 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4947 reference to the stabs symbol info used by the debugger. It is (as far
4948 as we know) the only published document on this fascinating topic. We
4949 encourage you to read it, compare it to the stabs information on your
4950 system, and send improvements on the document in general (to
4951 bug-gdb@prep.ai.mit.edu).
4953 And, of course, many bugs have been fixed.
4956 *** Changes in GDB-4.6:
4958 * Better support for C++ function names
4960 GDB now accepts as input the "demangled form" of C++ overloaded function
4961 names and member function names, and can do command completion on such names
4962 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4963 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4964 Make use of command completion, it is your friend.
4966 GDB also now accepts a variety of C++ mangled symbol formats. They are
4967 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4968 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4969 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4970 for the list of formats.
4972 * G++ symbol mangling problem
4974 Recent versions of gcc have a bug in how they emit debugging information for
4975 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4976 directory) can be applied to gcc to fix the problem. Alternatively, if you
4977 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4978 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4979 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4982 * New 'maintenance' command
4984 All of the commands related to hacking GDB internals have been moved out of
4985 the main command set, and now live behind the 'maintenance' command. This
4986 can also be abbreviated as 'mt'. The following changes were made:
4988 dump-me -> maintenance dump-me
4989 info all-breakpoints -> maintenance info breakpoints
4990 printmsyms -> maintenance print msyms
4991 printobjfiles -> maintenance print objfiles
4992 printpsyms -> maintenance print psymbols
4993 printsyms -> maintenance print symbols
4995 The following commands are new:
4997 maintenance demangle Call internal GDB demangler routine to
4998 demangle a C++ link name and prints the result.
4999 maintenance print type Print a type chain for a given symbol
5001 * Change to .gdbinit file processing
5003 We now read the $HOME/.gdbinit file before processing the argv arguments
5004 (e.g. reading symbol files or core files). This allows global parameters to
5005 be set, which will apply during the symbol reading. The ./.gdbinit is still
5006 read after argv processing.
5008 * New hosts supported
5010 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5012 GNU/Linux support i386-unknown-linux or linux
5014 We are also including code to support the HP/PA running BSD and HPUX. This
5015 is almost guaranteed not to work, as we didn't have time to test or build it
5016 for this release. We are including it so that the more adventurous (or
5017 masochistic) of you can play with it. We also had major problems with the
5018 fact that the compiler that we got from HP doesn't support the -g option.
5021 * New targets supported
5023 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5025 * More smarts about finding #include files
5027 GDB now remembers the compilation directory for all include files, and for
5028 all files from which C is generated (like yacc and lex sources). This
5029 greatly improves GDB's ability to find yacc/lex sources, and include files,
5030 especially if you are debugging your program from a directory different from
5031 the one that contains your sources.
5033 We also fixed a bug which caused difficulty with listing and setting
5034 breakpoints in include files which contain C code. (In the past, you had to
5035 try twice in order to list an include file that you hadn't looked at before.)
5037 * Interesting infernals change
5039 GDB now deals with arbitrary numbers of sections, where the symbols for each
5040 section must be relocated relative to that section's landing place in the
5041 target's address space. This work was needed to support ELF with embedded
5042 stabs used by Solaris-2.0.
5044 * Bug fixes (of course!)
5046 There have been loads of fixes for the following things:
5047 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5048 i960, stabs, DOS(GO32), procfs, etc...
5050 See the ChangeLog for details.
5052 *** Changes in GDB-4.5:
5054 * New machines supported (host and target)
5056 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5058 SGI Irix-4.x mips-sgi-irix4 or iris4
5060 * New malloc package
5062 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5063 Mmalloc is capable of handling mutiple heaps of memory. It is also
5064 capable of saving a heap to a file, and then mapping it back in later.
5065 This can be used to greatly speedup the startup of GDB by using a
5066 pre-parsed symbol table which lives in a mmalloc managed heap. For
5067 more details, please read mmalloc/mmalloc.texi.
5071 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5072 'help info proc' for details.
5074 * MIPS ecoff symbol table format
5076 The code that reads MIPS symbol table format is now supported on all hosts.
5077 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5080 * File name changes for MS-DOS
5082 Many files in the config directories have been renamed to make it easier to
5083 support GDB on MS-DOSe systems (which have very restrictive file name
5084 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5085 environment) is close to working but has some remaining problems. Note
5086 that debugging of DOS programs is not supported, due to limitations
5087 in the ``operating system'', but it can be used to host cross-debugging.
5089 * Cross byte order fixes
5091 Many fixes have been made to support cross debugging of Sparc and MIPS
5092 targets from hosts whose byte order differs.
5094 * New -mapped and -readnow options
5096 If memory-mapped files are available on your system through the 'mmap'
5097 system call, you can use the -mapped option on the `file' or
5098 `symbol-file' commands to cause GDB to write the symbols from your
5099 program into a reusable file. If the program you are debugging is
5100 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5101 Future GDB debugging sessions will notice the presence of this file,
5102 and will quickly map in symbol information from it, rather than reading
5103 the symbol table from the executable program. Using the '-mapped'
5104 option in a GDB `file' or `symbol-file' command has the same effect as
5105 starting GDB with the '-mapped' command-line option.
5107 You can cause GDB to read the entire symbol table immediately by using
5108 the '-readnow' option with any of the commands that load symbol table
5109 information (or on the GDB command line). This makes the command
5110 slower, but makes future operations faster.
5112 The -mapped and -readnow options are typically combined in order to
5113 build a `fred.syms' file that contains complete symbol information.
5114 A simple GDB invocation to do nothing but build a `.syms' file for future
5117 gdb -batch -nx -mapped -readnow programname
5119 The `.syms' file is specific to the host machine on which GDB is run.
5120 It holds an exact image of GDB's internal symbol table. It cannot be
5121 shared across multiple host platforms.
5123 * longjmp() handling
5125 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5126 siglongjmp() without losing control. This feature has not yet been ported to
5127 all systems. It currently works on many 386 platforms, all MIPS-based
5128 platforms (SGI, DECstation, etc), and Sun3/4.
5132 Preliminary work has been put in to support the new Solaris OS from Sun. At
5133 this time, it can control and debug processes, but it is not capable of
5138 As always, many many bug fixes. The major areas were with g++, and mipsread.
5139 People using the MIPS-based platforms should experience fewer mysterious
5140 crashes and trashed symbol tables.
5142 *** Changes in GDB-4.4:
5144 * New machines supported (host and target)
5146 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5148 BSD Reno on Vax vax-dec-bsd
5149 Ultrix on Vax vax-dec-ultrix
5151 * New machines supported (target)
5153 AMD 29000 embedded, using EBMON a29k-none-none
5157 GDB continues to improve its handling of C++. `References' work better.
5158 The demangler has also been improved, and now deals with symbols mangled as
5159 per the Annotated C++ Reference Guide.
5161 GDB also now handles `stabs' symbol information embedded in MIPS
5162 `ecoff' symbol tables. Since the ecoff format was not easily
5163 extensible to handle new languages such as C++, this appeared to be a
5164 good way to put C++ debugging info into MIPS binaries. This option
5165 will be supported in the GNU C compiler, version 2, when it is
5168 * New features for SVR4
5170 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5171 shared libraries. Debugging dynamically linked programs should present
5172 only minor differences from debugging statically linked programs.
5174 The `info proc' command will print out information about any process
5175 on an SVR4 system (including the one you are debugging). At the moment,
5176 it prints the address mappings of the process.
5178 If you bring up GDB on another SVR4 system, please send mail to
5179 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5181 * Better dynamic linking support in SunOS
5183 Reading symbols from shared libraries which contain debugging symbols
5184 now works properly. However, there remain issues such as automatic
5185 skipping of `transfer vector' code during function calls, which
5186 make it harder to debug code in a shared library, than to debug the
5187 same code linked statically.
5191 GDB is now using the latest `getopt' routines from the FSF. This
5192 version accepts the -- prefix for options with long names. GDB will
5193 continue to accept the old forms (-option and +option) as well.
5194 Various single letter abbreviations for options have been explicity
5195 added to the option table so that they won't get overshadowed in the
5196 future by other options that begin with the same letter.
5200 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5201 Many assorted bugs have been handled. Many more remain to be handled.
5202 See the various ChangeLog files (primarily in gdb and bfd) for details.
5205 *** Changes in GDB-4.3:
5207 * New machines supported (host and target)
5209 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5210 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5211 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5213 * Almost SCO Unix support
5215 We had hoped to support:
5216 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5217 (except for core file support), but we discovered very late in the release
5218 that it has problems with process groups that render gdb unusable. Sorry
5219 about that. I encourage people to fix it and post the fixes.
5221 * Preliminary ELF and DWARF support
5223 GDB can read ELF object files on System V Release 4, and can handle
5224 debugging records for C, in DWARF format, in ELF files. This support
5225 is preliminary. If you bring up GDB on another SVR4 system, please
5226 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5231 GDB now uses the latest `readline' library. One user-visible change
5232 is that two tabs will list possible command completions, which previously
5233 required typing M-? (meta-question mark, or ESC ?).
5237 The `stepi' bug that many of you noticed has been squashed.
5238 Many bugs in C++ have been handled. Many more remain to be handled.
5239 See the various ChangeLog files (primarily in gdb and bfd) for details.
5241 * State of the MIPS world (in case you wondered):
5243 GDB can understand the symbol tables emitted by the compilers
5244 supplied by most vendors of MIPS-based machines, including DEC. These
5245 symbol tables are in a format that essentially nobody else uses.
5247 Some versions of gcc come with an assembler post-processor called
5248 mips-tfile. This program is required if you want to do source-level
5249 debugging of gcc-compiled programs. I believe FSF does not ship
5250 mips-tfile with gcc version 1, but it will eventually come with gcc
5253 Debugging of g++ output remains a problem. g++ version 1.xx does not
5254 really support it at all. (If you're lucky, you should be able to get
5255 line numbers and stack traces to work, but no parameters or local
5256 variables.) With some work it should be possible to improve the
5259 When gcc version 2 is released, you will have somewhat better luck.
5260 However, even then you will get confusing results for inheritance and
5263 We will eventually provide full debugging of g++ output on
5264 DECstations. This will probably involve some kind of stabs-in-ecoff
5265 encapulation, but the details have not been worked out yet.
5268 *** Changes in GDB-4.2:
5270 * Improved configuration
5272 Only one copy of `configure' exists now, and it is not self-modifying.
5273 Porting BFD is simpler.
5277 The `step' and `next' commands now only stop at the first instruction
5278 of a source line. This prevents the multiple stops that used to occur
5279 in switch statements, for-loops, etc. `Step' continues to stop if a
5280 function that has debugging information is called within the line.
5284 Lots of small bugs fixed. More remain.
5286 * New host supported (not target)
5288 Intel 386 PC clone running Mach i386-none-mach
5291 *** Changes in GDB-4.1:
5293 * Multiple source language support
5295 GDB now has internal scaffolding to handle several source languages.
5296 It determines the type of each source file from its filename extension,
5297 and will switch expression parsing and number formatting to match the
5298 language of the function in the currently selected stack frame.
5299 You can also specifically set the language to be used, with
5300 `set language c' or `set language modula-2'.
5304 GDB now has preliminary support for the GNU Modula-2 compiler,
5305 currently under development at the State University of New York at
5306 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5307 continue through the fall of 1991 and into 1992.
5309 Other Modula-2 compilers are currently not supported, and attempting to
5310 debug programs compiled with them will likely result in an error as the
5311 symbol table is read. Feel free to work on it, though!
5313 There are hooks in GDB for strict type checking and range checking,
5314 in the `Modula-2 philosophy', but they do not currently work.
5318 GDB can now write to executable and core files (e.g. patch
5319 a variable's value). You must turn this switch on, specify
5320 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5321 by assigning a new value to a variable. Modifications take
5324 * Automatic SunOS shared library reading
5326 When you run your program, GDB automatically determines where its
5327 shared libraries (if any) have been loaded, and reads their symbols.
5328 The `share' command is no longer needed. This also works when
5329 examining core files.
5333 You can specify the number of lines that the `list' command shows.
5336 * New machines supported (host and target)
5338 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5339 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5340 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5342 * New hosts supported (not targets)
5344 IBM RT/PC: romp-ibm-aix or rtpc
5346 * New targets supported (not hosts)
5348 AMD 29000 embedded with COFF a29k-none-coff
5349 AMD 29000 embedded with a.out a29k-none-aout
5350 Ultracomputer remote kernel debug a29k-nyu-kern
5352 * New remote interfaces
5358 *** Changes in GDB-4.0:
5362 Wide output is wrapped at good places to make the output more readable.
5364 Gdb now supports cross-debugging from a host machine of one type to a
5365 target machine of another type. Communication with the target system
5366 is over serial lines. The ``target'' command handles connecting to the
5367 remote system; the ``load'' command will download a program into the
5368 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5369 also supports debugging of realtime processes running under VxWorks,
5370 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5371 stub on the target system.
5373 New CPUs supported include the AMD 29000 and Intel 960.
5375 GDB now reads object files and symbol tables via a ``binary file''
5376 library, which allows a single copy of GDB to debug programs of multiple
5377 object file types such as a.out and coff.
5379 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5380 refcard.dvi and refcard.ps are available to format it).
5383 * Control-Variable user interface simplified
5385 All variables that control the operation of the debugger can be set
5386 by the ``set'' command, and displayed by the ``show'' command.
5388 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5389 ``Show prompt'' produces the response:
5390 Gdb's prompt is new-gdb=>.
5392 What follows are the NEW set commands. The command ``help set'' will
5393 print a complete list of old and new set commands. ``help set FOO''
5394 will give a longer description of the variable FOO. ``show'' will show
5395 all of the variable descriptions and their current settings.
5397 confirm on/off: Enables warning questions for operations that are
5398 hard to recover from, e.g. rerunning the program while
5399 it is already running. Default is ON.
5401 editing on/off: Enables EMACS style command line editing
5402 of input. Previous lines can be recalled with
5403 control-P, the current line can be edited with control-B,
5404 you can search for commands with control-R, etc.
5407 history filename NAME: NAME is where the gdb command history
5408 will be stored. The default is .gdb_history,
5409 or the value of the environment variable
5412 history size N: The size, in commands, of the command history. The
5413 default is 256, or the value of the environment variable
5416 history save on/off: If this value is set to ON, the history file will
5417 be saved after exiting gdb. If set to OFF, the
5418 file will not be saved. The default is OFF.
5420 history expansion on/off: If this value is set to ON, then csh-like
5421 history expansion will be performed on
5422 command line input. The default is OFF.
5424 radix N: Sets the default radix for input and output. It can be set
5425 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5426 in the current radix, so "set radix 10" is always a no-op.
5428 height N: This integer value is the number of lines on a page. Default
5429 is 24, the current `stty rows'' setting, or the ``li#''
5430 setting from the termcap entry matching the environment
5433 width N: This integer value is the number of characters on a line.
5434 Default is 80, the current `stty cols'' setting, or the ``co#''
5435 setting from the termcap entry matching the environment
5438 Note: ``set screensize'' is obsolete. Use ``set height'' and
5439 ``set width'' instead.
5441 print address on/off: Print memory addresses in various command displays,
5442 such as stack traces and structure values. Gdb looks
5443 more ``symbolic'' if you turn this off; it looks more
5444 ``machine level'' with it on. Default is ON.
5446 print array on/off: Prettyprint arrays. New convenient format! Default
5449 print demangle on/off: Print C++ symbols in "source" form if on,
5452 print asm-demangle on/off: Same, for assembler level printouts
5455 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5458 * Support for Epoch Environment.
5460 The epoch environment is a version of Emacs v18 with windowing. One
5461 new command, ``inspect'', is identical to ``print'', except that if you
5462 are running in the epoch environment, the value is printed in its own
5466 * Support for Shared Libraries
5468 GDB can now debug programs and core files that use SunOS shared libraries.
5469 Symbols from a shared library cannot be referenced
5470 before the shared library has been linked with the program (this
5471 happens after you type ``run'' and before the function main() is entered).
5472 At any time after this linking (including when examining core files
5473 from dynamically linked programs), gdb reads the symbols from each
5474 shared library when you type the ``sharedlibrary'' command.
5475 It can be abbreviated ``share''.
5477 sharedlibrary REGEXP: Load shared object library symbols for files
5478 matching a unix regular expression. No argument
5479 indicates to load symbols for all shared libraries.
5481 info sharedlibrary: Status of loaded shared libraries.
5486 A watchpoint stops execution of a program whenever the value of an
5487 expression changes. Checking for this slows down execution
5488 tremendously whenever you are in the scope of the expression, but is
5489 quite useful for catching tough ``bit-spreader'' or pointer misuse
5490 problems. Some machines such as the 386 have hardware for doing this
5491 more quickly, and future versions of gdb will use this hardware.
5493 watch EXP: Set a watchpoint (breakpoint) for an expression.
5495 info watchpoints: Information about your watchpoints.
5497 delete N: Deletes watchpoint number N (same as breakpoints).
5498 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5499 enable N: Re-enables watchpoint number N (same as breakpoints).
5502 * C++ multiple inheritance
5504 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5507 * C++ exception handling
5509 Gdb now supports limited C++ exception handling. Besides the existing
5510 ability to breakpoint on an exception handler, gdb can breakpoint on
5511 the raising of an exception (before the stack is peeled back to the
5514 catch FOO: If there is a FOO exception handler in the dynamic scope,
5515 set a breakpoint to catch exceptions which may be raised there.
5516 Multiple exceptions (``catch foo bar baz'') may be caught.
5518 info catch: Lists all exceptions which may be caught in the
5519 current stack frame.
5522 * Minor command changes
5524 The command ``call func (arg, arg, ...)'' now acts like the print
5525 command, except it does not print or save a value if the function's result
5526 is void. This is similar to dbx usage.
5528 The ``up'' and ``down'' commands now always print the frame they end up
5529 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5530 frames without printing.
5532 * New directory command
5534 'dir' now adds directories to the FRONT of the source search path.
5535 The path starts off empty. Source files that contain debug information
5536 about the directory in which they were compiled can be found even
5537 with an empty path; Sun CC and GCC include this information. If GDB can't
5538 find your source file in the current directory, type "dir .".
5540 * Configuring GDB for compilation
5542 For normal use, type ``./configure host''. See README or gdb.texinfo
5545 GDB now handles cross debugging. If you are remotely debugging between
5546 two different machines, type ``./configure host -target=targ''.
5547 Host is the machine where GDB will run; targ is the machine
5548 where the program that you are debugging will run.