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.
41 Nios II ELF nios2*-*-elf
42 Nios II GNU/Linux nios2*-*-linux
43 Texas Instruments MSP430 msp430*-*-elf
45 * Removed native configurations
47 Support for these a.out NetBSD and OpenBSD obsolete configurations has
48 been removed. ELF variants of these configurations are kept supported.
50 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
51 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
52 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
53 i[34567]86-*-openbsd3.[0-3]
54 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
55 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
56 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
60 Like "catch throw", but catches a re-thrown exception.
62 Renamed from old "maint check-symtabs".
64 Perform consistency checks on symtabs.
66 Expand symtabs matching an optional regexp.
69 Display the details of GDB configure-time options.
71 maint set|show per-command
72 maint set|show per-command space
73 maint set|show per-command time
74 maint set|show per-command symtab
75 Enable display of per-command gdb resource usage.
79 set debug symfile off|on
81 Control display of debugging info regarding reading symbol files and
82 symbol tables within those files
84 set print raw frame-arguments
85 show print raw frame-arguments
86 Set/show whether to print frame arguments in raw mode,
87 disregarding any defined pretty-printers.
89 set remote trace-status-packet
90 show remote trace-status-packet
91 Set/show the use of remote protocol qTStatus packet.
95 Control display of debugging messages related to Nios II targets.
99 Control whether target-assisted range stepping is enabled.
101 set startup-with-shell
102 show startup-with-shell
103 Specifies whether Unix child processes are started via a shell or
106 * You can now use a literal value 'unlimited' for options that
107 interpret 0 or -1 as meaning "unlimited". E.g., "set
108 trace-buffer-size unlimited" is now an alias for "set
109 trace-buffer-size -1" and "set height unlimited" is now an alias for
112 * New command-line options
114 Display the details of GDB configure-time options.
116 * The command 'tsave' can now support new option '-ctf' to save trace
117 buffer in Common Trace Format.
119 * Newly installed $prefix/bin/gcore acts as a shell interface for the
122 * GDB now implements the the C++ 'typeid' operator.
124 * The new convenience variable $_exception holds the exception being
125 thrown or caught at an exception-related catchpoint.
127 * The exception-related catchpoints, like "catch throw", now accept a
128 regular expression which can be used to filter exceptions by type.
130 * The new convenience variable $_exitsignal is automatically set to
131 the terminating signal number when the program being debugged dies
132 due to an uncaught signal.
136 ** The -trace-save MI command can optionally save trace buffer in Common
139 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
141 ** The command -data-list-register-values now accepts an optional
142 "--skip-unavailable" option. When used, only the available registers
145 ** The new command -trace-frame-collected dumps collected variables,
146 computed expressions, tvars, memory and registers in a traceframe.
148 ** The commands -stack-list-locals, -stack-list-arguments and
149 -stack-list-variables now accept an option "--skip-unavailable".
150 When used, only the available locals or arguments are displayed.
152 ** The -exec-run command now accepts an optional "--start" option.
153 When used, the command follows the same semantics as the "start"
154 command, stopping the program's execution at the start of its
157 ** The new commands -catch-assert and -catch-exceptions insert
158 catchpoints stopping the program when Ada exceptions are raised.
160 * New system-wide configuration scripts
161 A GDB installation now provides scripts suitable for use as system-wide
162 configuration scripts for the following systems:
166 * GDB now supports target-assigned range stepping with remote targets.
167 This improves the performance of stepping source lines by reducing
168 the number of control packets from/to GDB. See "New remote packets"
171 * GDB now understands the element 'tvar' in the XML traceframe info.
172 It has the id of the collected trace state variables.
174 * On S/390 targets that provide the transactional-execution feature,
175 the program interruption transaction diagnostic block (TDB) is now
176 represented as a number of additional "registers" in GDB.
182 The vCont packet supports a new 'r' action, that tells the remote
183 stub to step through an address range itself, without GDB
184 involvemement at each single-step.
186 qXfer:libraries-svr4:read's annex
187 The previously unused annex of the qXfer:libraries-svr4:read packet
188 is now used to support passing an argument list. The remote stub
189 reports support for this argument list to GDB's qSupported query.
190 The defined arguments are "start" and "prev", used to reduce work
191 necessary for library list updating, resulting in significant
194 * New features in the GDB remote stub, GDBserver
196 ** GDBserver now supports target-assisted range stepping. Currently
197 enabled on x86/x86_64 GNU/Linux targets.
199 ** GDBserver now adds element 'tvar' in the XML in the reply to
200 'qXfer:traceframe-info:read'. It has the id of the collected
201 trace state variables.
203 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
206 * New 'z' formatter for printing and examining memory, this displays the
207 value as hexadecimal zero padded on the left to the size of the type.
209 * GDB can now use Windows x64 unwinding data.
211 * The "set remotebaud" command has been replaced by "set serial baud".
212 Similarly, "show remotebaud" has been replaced by "show serial baud".
213 The "set remotebaud" and "show remotebaud" commands are still available
214 to provide backward compatibility with older versions of GDB.
216 *** Changes in GDB 7.6
218 * Target record has been renamed to record-full.
219 Record/replay is now enabled with the "record full" command.
220 This also affects settings that are associated with full record/replay
221 that have been moved from "set/show record" to "set/show record full":
223 set|show record full insn-number-max
224 set|show record full stop-at-limit
225 set|show record full memory-query
227 * A new record target "record-btrace" has been added. The new target
228 uses hardware support to record the control-flow of a process. It
229 does not support replaying the execution, but it implements the
230 below new commands for investigating the recorded execution log.
231 This new recording method can be enabled using:
235 The "record-btrace" target is only available on Intel Atom processors
236 and requires a Linux kernel 2.6.32 or later.
238 * Two new commands have been added for record/replay to give information
239 about the recorded execution without having to replay the execution.
240 The commands are only supported by "record btrace".
242 record instruction-history prints the execution history at
243 instruction granularity
245 record function-call-history prints the execution history at
248 * New native configurations
250 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
251 FreeBSD/powerpc powerpc*-*-freebsd
252 x86_64/Cygwin x86_64-*-cygwin*
253 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
257 ARM AArch64 aarch64*-*-elf
258 ARM AArch64 GNU/Linux aarch64*-*-linux
259 Lynx 178 PowerPC powerpc-*-lynx*178
260 x86_64/Cygwin x86_64-*-cygwin*
261 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
263 * If the configured location of system.gdbinit file (as given by the
264 --with-system-gdbinit option at configure time) is in the
265 data-directory (as specified by --with-gdb-datadir at configure
266 time) or in one of its subdirectories, then GDB will look for the
267 system-wide init file in the directory specified by the
268 --data-directory command-line option.
270 * New command line options:
272 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
273 other initialization files, unlike -nx which disables all of them.
275 * Removed command line options
277 -epoch This was used by the gdb mode in Epoch, an ancient fork of
280 * The 'ptype' and 'whatis' commands now accept an argument to control
283 * 'info proc' now works on some core files.
287 ** Vectors can be created with gdb.Type.vector.
289 ** Python's atexit.register now works in GDB.
291 ** Types can be pretty-printed via a Python API.
293 ** Python 3 is now supported (in addition to Python 2.4 or later)
295 ** New class gdb.Architecture exposes GDB's internal representation
296 of architecture in the Python API.
298 ** New method Frame.architecture returns the gdb.Architecture object
299 corresponding to the frame's architecture.
301 * New Python-based convenience functions:
303 ** $_memeq(buf1, buf2, length)
304 ** $_streq(str1, str2)
306 ** $_regex(str, regex)
308 * The 'cd' command now defaults to using '~' (the home directory) if not
311 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
312 default for GCC since November 2000.
314 * The command 'forward-search' can now be abbreviated as 'fo'.
316 * The command 'info tracepoints' can now display 'installed on target'
317 or 'not installed on target' for each non-pending location of tracepoint.
319 * New configure options
321 --enable-libmcheck/--disable-libmcheck
322 By default, development versions are built with -lmcheck on hosts
323 that support it, in order to help track memory corruption issues.
324 Release versions, on the other hand, are built without -lmcheck
325 by default. The --enable-libmcheck/--disable-libmcheck configure
326 options allow the user to override that default.
327 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
328 This configure option allows the user to build GDB with
329 libbabeltrace using which GDB can read Common Trace Format data.
331 * New commands (for set/show, see "New options" below)
334 Catch signals. This is similar to "handle", but allows commands and
335 conditions to be attached.
338 List the BFDs known to GDB.
340 python-interactive [command]
342 Start a Python interactive prompt, or evaluate the optional command
343 and print the result of expressions.
346 "py" is a new alias for "python".
348 enable type-printer [name]...
349 disable type-printer [name]...
350 Enable or disable type printers.
354 ** For the Renesas Super-H architecture, the "regs" command has been removed
355 (has been deprecated in GDB 7.5), and "info all-registers" should be used
360 set print type methods (on|off)
361 show print type methods
362 Control whether method declarations are displayed by "ptype".
363 The default is to show them.
365 set print type typedefs (on|off)
366 show print type typedefs
367 Control whether typedef definitions are displayed by "ptype".
368 The default is to show them.
370 set filename-display basename|relative|absolute
371 show filename-display
372 Control the way in which filenames is displayed.
373 The default is "relative", which preserves previous behavior.
375 set trace-buffer-size
376 show trace-buffer-size
377 Request target to change the size of trace buffer.
379 set remote trace-buffer-size-packet auto|on|off
380 show remote trace-buffer-size-packet
381 Control the use of the remote protocol `QTBuffer:size' packet.
385 Control display of debugging messages related to ARM AArch64.
388 set debug coff-pe-read
389 show debug coff-pe-read
390 Control display of debugging messages related to reading of COFF/PE
395 Control display of debugging messages related to Mach-O symbols
398 set debug notification
399 show debug notification
400 Control display of debugging info for async remote notification.
404 ** Command parameter changes are now notified using new async record
405 "=cmd-param-changed".
406 ** Trace frame changes caused by command "tfind" are now notified using
407 new async record "=traceframe-changed".
408 ** The creation, deletion and modification of trace state variables
409 are now notified using new async records "=tsv-created",
410 "=tsv-deleted" and "=tsv-modified".
411 ** The start and stop of process record are now notified using new
412 async record "=record-started" and "=record-stopped".
413 ** Memory changes are now notified using new async record
415 ** The data-disassemble command response will include a "fullname" field
416 containing the absolute file name when source has been requested.
417 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
418 command, to allow pattern filling of memory areas.
419 ** New commands "-catch-load"/"-catch-unload" added for intercepting
420 library load/unload events.
421 ** The response to breakpoint commands and breakpoint async records
422 includes an "installed" field containing a boolean state about each
423 non-pending tracepoint location is whether installed on target or not.
424 ** Output of the "-trace-status" command includes a "trace-file" field
425 containing the name of the trace file being examined. This field is
426 optional, and only present when examining a trace file.
427 ** The "fullname" field is now always present along with the "file" field,
428 even if the file cannot be found by GDB.
430 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
431 You must have the LZMA library available when configuring GDB for this
432 feature to be enabled. For more information, see:
433 http://fedoraproject.org/wiki/Features/MiniDebugInfo
438 Set the size of trace buffer. The remote stub reports support for this
439 packet to gdb's qSupported query.
442 Enable Branch Trace Store (BTS)-based branch tracing for the current
443 thread. The remote stub reports support for this packet to gdb's
447 Disable branch tracing for the current thread. The remote stub reports
448 support for this packet to gdb's qSupported query.
451 Read the traced branches for the current thread. The remote stub
452 reports support for this packet to gdb's qSupported query.
454 *** Changes in GDB 7.5
456 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
457 for more x32 ABI info.
459 * GDB now supports access to MIPS DSP registers on Linux targets.
461 * GDB now supports debugging microMIPS binaries.
463 * The "info os" command on GNU/Linux can now display information on
464 several new classes of objects managed by the operating system:
465 "info os procgroups" lists process groups
466 "info os files" lists file descriptors
467 "info os sockets" lists internet-domain sockets
468 "info os shm" lists shared-memory regions
469 "info os semaphores" lists semaphores
470 "info os msg" lists message queues
471 "info os modules" lists loaded kernel modules
473 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
474 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
475 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
476 options and inspect the probe arguments using the new $_probe_arg family
477 of convenience variables. You can obtain more information about SystemTap
478 in <http://sourceware.org/systemtap/>.
480 * GDB now supports reversible debugging on ARM, it allows you to
481 debug basic ARM and THUMB instructions, and provides
482 record/replay support.
484 * The option "symbol-reloading" has been deleted as it is no longer used.
488 ** GDB commands implemented in Python can now be put in command class
491 ** The "maint set python print-stack on|off" is now deleted.
493 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
494 apply "flag enum"-style pretty-printing to any enum.
496 ** gdb.lookup_symbol can now work when there is no current frame.
498 ** gdb.Symbol now has a 'line' attribute, holding the line number in
499 the source at which the symbol was defined.
501 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
502 method 'value'. The former indicates whether the symbol needs a
503 frame in order to compute its value, and the latter computes the
506 ** A new method 'referenced_value' on gdb.Value objects which can
507 dereference pointer as well as C++ reference values.
509 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
510 which return the global and static blocks (as gdb.Block objects),
511 of the underlying symbol table, respectively.
513 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
514 object associated with a PC value.
516 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
517 of the address range occupied by code for the current source line.
519 * Go language support.
520 GDB now supports debugging programs written in the Go programming
523 * GDBserver now supports stdio connections.
524 E.g. (gdb) target remote | ssh myhost gdbserver - hello
526 * The binary "gdbtui" can no longer be built or installed.
527 Use "gdb -tui" instead.
529 * GDB will now print "flag" enums specially. A flag enum is one where
530 all the enumerator values have no bits in common when pairwise
531 "and"ed. When printing a value whose type is a flag enum, GDB will
532 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
533 (gdb) print (enum E) 3
536 * The filename part of a linespec will now match trailing components
537 of a source file name. For example, "break gcc/expr.c:1000" will
538 now set a breakpoint in build/gcc/expr.c, but not
541 * The "info proc" and "generate-core-file" commands will now also
542 work on remote targets connected to GDBserver on Linux.
544 * The command "info catch" has been removed. It has been disabled
547 * The "catch exception" and "catch assert" commands now accept
548 a condition at the end of the command, much like the "break"
549 command does. For instance:
551 (gdb) catch exception Constraint_Error if Barrier = True
553 Previously, it was possible to add a condition to such catchpoints,
554 but it had to be done as a second step, after the catchpoint had been
555 created, using the "condition" command.
557 * The "info static-tracepoint-marker" command will now also work on
558 native Linux targets with in-process agent.
560 * GDB can now set breakpoints on inlined functions.
562 * The .gdb_index section has been updated to include symbols for
563 inlined functions. GDB will ignore older .gdb_index sections by
564 default, which could cause symbol files to be loaded more slowly
565 until their .gdb_index sections can be recreated. The new command
566 "set use-deprecated-index-sections on" will cause GDB to use any older
567 .gdb_index sections it finds. This will restore performance, but the
568 ability to set breakpoints on inlined functions will be lost in symbol
569 files with older .gdb_index sections.
571 The .gdb_index section has also been updated to record more information
572 about each symbol. This speeds up the "info variables", "info functions"
573 and "info types" commands when used with programs having the .gdb_index
574 section, as well as speeding up debugging with shared libraries using
575 the .gdb_index section.
577 * Ada support for GDB/MI Variable Objects has been added.
579 * GDB can now support 'breakpoint always-inserted mode' in 'record'
584 ** New command -info-os is the MI equivalent of "info os".
586 ** Output logs ("set logging" and related) now include MI output.
590 ** "set use-deprecated-index-sections on|off"
591 "show use-deprecated-index-sections on|off"
592 Controls the use of deprecated .gdb_index sections.
594 ** "catch load" and "catch unload" can be used to stop when a shared
595 library is loaded or unloaded, respectively.
597 ** "enable count" can be used to auto-disable a breakpoint after
600 ** "info vtbl" can be used to show the virtual method tables for
601 C++ and Java objects.
603 ** "explore" and its sub commands "explore value" and "explore type"
604 can be used to reccursively explore values and types of
605 expressions. These commands are available only if GDB is
606 configured with '--with-python'.
608 ** "info auto-load" shows status of all kinds of auto-loaded files,
609 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
610 sequences of commands files, "info auto-load python-scripts"
611 shows status of auto-loading Python script files,
612 "info auto-load local-gdbinit" shows status of loading init file
613 (.gdbinit) from current directory and "info auto-load libthread-db" shows
614 status of inferior specific thread debugging shared library loading.
616 ** "info auto-load-scripts", "set auto-load-scripts on|off"
617 and "show auto-load-scripts" commands have been deprecated, use their
618 "info auto-load python-scripts", "set auto-load python-scripts on|off"
619 and "show auto-load python-scripts" counterparts instead.
621 ** "dprintf location,format,args..." creates a dynamic printf, which
622 is basically a breakpoint that does a printf and immediately
623 resumes your program's execution, so it is like a printf that you
624 can insert dynamically at runtime instead of at compiletime.
626 ** "set print symbol"
628 Controls whether GDB attempts to display the symbol, if any,
629 corresponding to addresses it prints. This defaults to "on", but
630 you can set it to "off" to restore GDB's previous behavior.
632 * Deprecated commands
634 ** For the Renesas Super-H architecture, the "regs" command has been
635 deprecated, and "info all-registers" should be used instead.
639 Renesas RL78 rl78-*-elf
640 HP OpenVMS ia64 ia64-hp-openvms*
642 * GDBserver supports evaluation of breakpoint conditions. When
643 support is advertised by GDBserver, GDB may be told to send the
644 breakpoint conditions in bytecode form to GDBserver. GDBserver
645 will only report the breakpoint trigger to GDB when its condition
651 show mips compression
652 Select the compressed ISA encoding used in functions that have no symbol
653 information available. The encoding can be set to either of:
656 and is updated automatically from ELF file flags if available.
658 set breakpoint condition-evaluation
659 show breakpoint condition-evaluation
660 Control whether breakpoint conditions are evaluated by GDB ("host") or by
661 GDBserver ("target"). Default option "auto" chooses the most efficient
663 This option can improve debugger efficiency depending on the speed of the
667 Disable auto-loading globally.
670 Show auto-loading setting of all kinds of auto-loaded files.
672 set auto-load gdb-scripts on|off
673 show auto-load gdb-scripts
674 Control auto-loading of GDB canned sequences of commands files.
676 set auto-load python-scripts on|off
677 show auto-load python-scripts
678 Control auto-loading of Python script files.
680 set auto-load local-gdbinit on|off
681 show auto-load local-gdbinit
682 Control loading of init file (.gdbinit) from current directory.
684 set auto-load libthread-db on|off
685 show auto-load libthread-db
686 Control auto-loading of inferior specific thread debugging shared library.
688 set auto-load scripts-directory <dir1>[:<dir2>...]
689 show auto-load scripts-directory
690 Set a list of directories from which to load auto-loaded scripts.
691 Automatically loaded Python scripts and GDB scripts are located in one
692 of the directories listed by this option.
693 The delimiter (':' above) may differ according to the host platform.
695 set auto-load safe-path <dir1>[:<dir2>...]
696 show auto-load safe-path
697 Set a list of directories from which it is safe to auto-load files.
698 The delimiter (':' above) may differ according to the host platform.
700 set debug auto-load on|off
702 Control display of debugging info for auto-loading the files above.
704 set dprintf-style gdb|call|agent
706 Control the way in which a dynamic printf is performed; "gdb"
707 requests a GDB printf command, while "call" causes dprintf to call a
708 function in the inferior. "agent" requests that the target agent
709 (such as GDBserver) do the printing.
711 set dprintf-function <expr>
712 show dprintf-function
713 set dprintf-channel <expr>
715 Set the function and optional first argument to the call when using
716 the "call" style of dynamic printf.
718 set disconnected-dprintf on|off
719 show disconnected-dprintf
720 Control whether agent-style dynamic printfs continue to be in effect
721 after GDB disconnects.
723 * New configure options
726 Configure default value for the 'set auto-load scripts-directory'
727 setting above. It defaults to '$debugdir:$datadir/auto-load',
728 $debugdir representing global debugging info directories (available
729 via 'show debug-file-directory') and $datadir representing GDB's data
730 directory (available via 'show data-directory').
732 --with-auto-load-safe-path
733 Configure default value for the 'set auto-load safe-path' setting
734 above. It defaults to the --with-auto-load-dir setting.
736 --without-auto-load-safe-path
737 Set 'set auto-load safe-path' to '/', effectively disabling this
742 z0/z1 conditional breakpoints extension
744 The z0/z1 breakpoint insertion packets have been extended to carry
745 a list of conditional expressions over to the remote stub depending on the
746 condition evaluation mode. The use of this extension can be controlled
747 via the "set remote conditional-breakpoints-packet" command.
751 Specify the signals which the remote stub may pass to the debugged
752 program without GDB involvement.
754 * New command line options
756 --init-command=FILE, -ix Like --command, -x but execute it
757 before loading inferior.
758 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
759 execute it before loading inferior.
761 *** Changes in GDB 7.4
763 * GDB now handles ambiguous linespecs more consistently; the existing
764 FILE:LINE support has been expanded to other types of linespecs. A
765 breakpoint will now be set on all matching locations in all
766 inferiors, and locations will be added or removed according to
769 * GDB now allows you to skip uninteresting functions and files when
770 stepping with the "skip function" and "skip file" commands.
772 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
773 and "show remote hardware-watchpoint-length-limit". These allows to
774 set or show the maximum length limit (in bytes) of a remote
775 target hardware watchpoint.
777 This allows e.g. to use "unlimited" hardware watchpoints with the
778 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
779 watchpoints are slower than real hardware watchpoints but are
780 significantly faster than gdb software watchpoints.
784 ** The register_pretty_printer function in module gdb.printing now takes
785 an optional `replace' argument. If True, the new printer replaces any
788 ** The "maint set python print-stack on|off" command has been
789 deprecated and will be deleted in GDB 7.5.
790 A new command: "set python print-stack none|full|message" has
791 replaced it. Additionally, the default for "print-stack" is
792 now "message", which just prints the error message without
795 ** A prompt substitution hook (prompt_hook) is now available to the
798 ** A new Python module, gdb.prompt has been added to the GDB Python
799 modules library. This module provides functionality for
800 escape sequences in prompts (used by set/show
801 extended-prompt). These escape sequences are replaced by their
804 ** Python commands and convenience-functions located in
805 'data-directory'/python/gdb/command and
806 'data-directory'/python/gdb/function are now automatically loaded
809 ** Blocks now provide four new attributes. global_block and
810 static_block will return the global and static blocks
811 respectively. is_static and is_global are boolean attributes
812 that indicate if the block is one of those two types.
814 ** Symbols now provide the "type" attribute, the type of the symbol.
816 ** The "gdb.breakpoint" function has been deprecated in favor of
819 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
820 of a function. This class is based on the "finish" command
821 available in the CLI.
823 ** Type objects for struct and union types now allow access to
824 the fields using standard Python dictionary (mapping) methods.
825 For example, "some_type['myfield']" now works, as does
828 ** A new event "gdb.new_objfile" has been added, triggered by loading a
831 ** A new function, "deep_items" has been added to the gdb.types
832 module in the GDB Python modules library. This function returns
833 an iterator over the fields of a struct or union type. Unlike
834 the standard Python "iteritems" method, it will recursively traverse
835 any anonymous fields.
839 ** "*stopped" events can report several new "reason"s, such as
842 ** Breakpoint changes are now notified using new async records, like
843 "=breakpoint-modified".
845 ** New command -ada-task-info.
847 * libthread-db-search-path now supports two special values: $sdir and $pdir.
848 $sdir specifies the default system locations of shared libraries.
849 $pdir specifies the directory where the libpthread used by the application
852 GDB no longer looks in $sdir and $pdir after it has searched the directories
853 mentioned in libthread-db-search-path. If you want to search those
854 directories, they must be specified in libthread-db-search-path.
855 The default value of libthread-db-search-path on GNU/Linux and Solaris
856 systems is now "$sdir:$pdir".
858 $pdir is not supported by gdbserver, it is currently ignored.
859 $sdir is supported by gdbserver.
861 * New configure option --with-iconv-bin.
862 When using the internationalization support like the one in the GNU C
863 library, GDB will invoke the "iconv" program to get a list of supported
864 character sets. If this program lives in a non-standard location, one can
865 use this option to specify where to find it.
867 * When natively debugging programs on PowerPC BookE processors running
868 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
869 watchpoints, which specify a mask in addition to an address to watch.
870 The mask specifies that some bits of an address (the bits which are
871 reset in the mask) should be ignored when matching the address accessed
872 by the inferior against the watchpoint address. See the "PowerPC Embedded"
873 section in the user manual for more details.
875 * The new option --once causes GDBserver to stop listening for connections once
876 the first connection is made. The listening port used by GDBserver will
877 become available after that.
879 * New commands "info macros" and "alias" have been added.
881 * New function parameters suffix @entry specifies value of function parameter
882 at the time the function got called. Entry values are available only since
888 "!" is now an alias of the "shell" command.
889 Note that no space is needed between "!" and SHELL COMMAND.
893 watch EXPRESSION mask MASK_VALUE
894 The watch command now supports the mask argument which allows creation
895 of masked watchpoints, if the current architecture supports this feature.
897 info auto-load-scripts [REGEXP]
898 This command was formerly named "maintenance print section-scripts".
899 It is now generally useful and is no longer a maintenance-only command.
901 info macro [-all] [--] MACRO
902 The info macro command has new options `-all' and `--'. The first for
903 printing all definitions of a macro. The second for explicitly specifying
904 the end of arguments and the beginning of the macro name in case the macro
905 name starts with a hyphen.
907 collect[/s] EXPRESSIONS
908 The tracepoint collect command now takes an optional modifier "/s"
909 that directs it to dereference pointer-to-character types and
910 collect the bytes of memory up to a zero byte. The behavior is
911 similar to what you see when you use the regular print command on a
912 string. An optional integer following the "/s" sets a bound on the
913 number of bytes that will be collected.
916 The trace start command now interprets any supplied arguments as a
917 note to be recorded with the trace run, with an effect similar to
918 setting the variable trace-notes.
921 The trace stop command now interprets any arguments as a note to be
922 mentioned along with the tstatus report that the trace was stopped
923 with a command. The effect is similar to setting the variable
926 * Tracepoints can now be enabled and disabled at any time after a trace
927 experiment has been started using the standard "enable" and "disable"
928 commands. It is now possible to start a trace experiment with no enabled
929 tracepoints; GDB will display a warning, but will allow the experiment to
930 begin, assuming that tracepoints will be enabled as needed while the trace
933 * Fast tracepoints on 32-bit x86-architectures can now be placed at
934 locations with 4-byte instructions, when they were previously
935 limited to locations with instructions of 5 bytes or longer.
939 set debug dwarf2-read
940 show debug dwarf2-read
941 Turns on or off display of debugging messages related to reading
942 DWARF debug info. The default is off.
944 set debug symtab-create
945 show debug symtab-create
946 Turns on or off display of debugging messages related to symbol table
947 creation. The default is off.
951 Set the GDB prompt, and allow escape sequences to be inserted to
952 display miscellaneous information (see 'help set extended-prompt'
953 for the list of sequences). This prompt (and any information
954 accessed through the escape sequences) is updated every time the
957 set print entry-values (both|compact|default|if-needed|no|only|preferred)
958 show print entry-values
959 Set printing of frame argument values at function entry. In some cases
960 GDB can determine the value of function argument which was passed by the
961 function caller, even if the value was modified inside the called function.
963 set debug entry-values
964 show debug entry-values
965 Control display of debugging info for determining frame argument values at
966 function entry and virtual tail call frames.
968 set basenames-may-differ
969 show basenames-may-differ
970 Set whether a source file may have multiple base names.
971 (A "base name" is the name of a file with the directory part removed.
972 Example: The base name of "/home/user/hello.c" is "hello.c".)
973 If set, GDB will canonicalize file names (e.g., expand symlinks)
974 before comparing them. Canonicalization is an expensive operation,
975 but it allows the same file be known by more than one base name.
976 If not set (the default), all source files are assumed to have just
977 one base name, and gdb will do file name comparisons more efficiently.
983 Set a user name and notes for the current and any future trace runs.
984 This is useful for long-running and/or disconnected traces, to
985 inform others (or yourself) as to who is running the trace, supply
986 contact information, or otherwise explain what is going on.
989 show trace-stop-notes
990 Set a note attached to the trace run, that is displayed when the
991 trace has been stopped by a tstop command. This is useful for
992 instance as an explanation, if you are stopping a trace run that was
993 started by someone else.
999 Dynamically enable a tracepoint in a started trace experiment.
1003 Dynamically disable a tracepoint in a started trace experiment.
1007 Set the user and notes of the trace run.
1011 Query the current status of a tracepoint.
1015 Query the minimum length of instruction at which a fast tracepoint may
1018 * Dcache size (number of lines) and line-size are now runtime-configurable
1019 via "set dcache line" and "set dcache line-size" commands.
1023 Texas Instruments TMS320C6x tic6x-*-*
1027 Renesas RL78 rl78-*-elf
1029 *** Changes in GDB 7.3.1
1031 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1033 *** Changes in GDB 7.3
1035 * GDB has a new command: "thread find [REGEXP]".
1036 It finds the thread id whose name, target id, or thread extra info
1037 matches the given regular expression.
1039 * The "catch syscall" command now works on mips*-linux* targets.
1041 * The -data-disassemble MI command now supports modes 2 and 3 for
1042 dumping the instruction opcodes.
1044 * New command line options
1046 -data-directory DIR Specify DIR as the "data-directory".
1047 This is mostly for testing purposes.
1049 * The "maint set python auto-load on|off" command has been renamed to
1050 "set auto-load-scripts on|off".
1052 * GDB has a new command: "set directories".
1053 It is like the "dir" command except that it replaces the
1054 source path list instead of augmenting it.
1056 * GDB now understands thread names.
1058 On GNU/Linux, "info threads" will display the thread name as set by
1059 prctl or pthread_setname_np.
1061 There is also a new command, "thread name", which can be used to
1062 assign a name internally for GDB to display.
1065 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1066 has been integrated into GDB.
1070 ** The function gdb.Write now accepts an optional keyword 'stream'.
1071 This keyword, when provided, will direct the output to either
1072 stdout, stderr, or GDB's logging output.
1074 ** Parameters can now be be sub-classed in Python, and in particular
1075 you may implement the get_set_doc and get_show_doc functions.
1076 This improves how Parameter set/show documentation is processed
1077 and allows for more dynamic content.
1079 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1080 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1081 have an is_valid method.
1083 ** Breakpoints can now be sub-classed in Python, and in particular
1084 you may implement a 'stop' function that is executed each time
1085 the inferior reaches that breakpoint.
1087 ** New function gdb.lookup_global_symbol looks up a global symbol.
1089 ** GDB values in Python are now callable if the value represents a
1090 function. For example, if 'some_value' represents a function that
1091 takes two integer parameters and returns a value, you can call
1092 that function like so:
1094 result = some_value (10,20)
1096 ** Module gdb.types has been added.
1097 It contains a collection of utilities for working with gdb.Types objects:
1098 get_basic_type, has_field, make_enum_dict.
1100 ** Module gdb.printing has been added.
1101 It contains utilities for writing and registering pretty-printers.
1102 New classes: PrettyPrinter, SubPrettyPrinter,
1103 RegexpCollectionPrettyPrinter.
1104 New function: register_pretty_printer.
1106 ** New commands "info pretty-printers", "enable pretty-printer" and
1107 "disable pretty-printer" have been added.
1109 ** gdb.parameter("directories") is now available.
1111 ** New function gdb.newest_frame returns the newest frame in the
1114 ** The gdb.InferiorThread class has a new "name" attribute. This
1115 holds the thread's name.
1117 ** Python Support for Inferior events.
1118 Python scripts can add observers to be notified of events
1119 occurring in the process being debugged.
1120 The following events are currently supported:
1121 - gdb.events.cont Continue event.
1122 - gdb.events.exited Inferior exited event.
1123 - gdb.events.stop Signal received, and Breakpoint hit events.
1127 ** GDB now puts template parameters in scope when debugging in an
1128 instantiation. For example, if you have:
1130 template<int X> int func (void) { return X; }
1132 then if you step into func<5>, "print X" will show "5". This
1133 feature requires proper debuginfo support from the compiler; it
1134 was added to GCC 4.5.
1136 ** The motion commands "next", "finish", "until", and "advance" now
1137 work better when exceptions are thrown. In particular, GDB will
1138 no longer lose control of the inferior; instead, the GDB will
1139 stop the inferior at the point at which the exception is caught.
1140 This functionality requires a change in the exception handling
1141 code that was introduced in GCC 4.5.
1143 * GDB now follows GCC's rules on accessing volatile objects when
1144 reading or writing target state during expression evaluation.
1145 One notable difference to prior behavior is that "print x = 0"
1146 no longer generates a read of x; the value of the assignment is
1147 now always taken directly from the value being assigned.
1149 * GDB now has some support for using labels in the program's source in
1150 linespecs. For instance, you can use "advance label" to continue
1151 execution to a label.
1153 * GDB now has support for reading and writing a new .gdb_index
1154 section. This section holds a fast index of DWARF debugging
1155 information and can be used to greatly speed up GDB startup and
1156 operation. See the documentation for `save gdb-index' for details.
1158 * The "watch" command now accepts an optional "-location" argument.
1159 When used, this causes GDB to watch the memory referred to by the
1160 expression. Such a watchpoint is never deleted due to it going out
1163 * GDB now supports thread debugging of core dumps on GNU/Linux.
1165 GDB now activates thread debugging using the libthread_db library
1166 when debugging GNU/Linux core dumps, similarly to when debugging
1167 live processes. As a result, when debugging a core dump file, GDB
1168 is now able to display pthread_t ids of threads. For example, "info
1169 threads" shows the same output as when debugging the process when it
1170 was live. In earlier releases, you'd see something like this:
1173 * 1 LWP 6780 main () at main.c:10
1175 While now you see this:
1178 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1180 It is also now possible to inspect TLS variables when debugging core
1183 When debugging a core dump generated on a machine other than the one
1184 used to run GDB, you may need to point GDB at the correct
1185 libthread_db library with the "set libthread-db-search-path"
1186 command. See the user manual for more details on this command.
1188 * When natively debugging programs on PowerPC BookE processors running
1189 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1190 which stop execution of the inferior whenever it executes an instruction
1191 at any address within the specified range. See the "PowerPC Embedded"
1192 section in the user manual for more details.
1194 * New features in the GDB remote stub, GDBserver
1196 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1197 and i686 LynxOS (version 5.x).
1199 ** GDBserver is now supported on Blackfin Linux.
1201 * New native configurations
1203 ia64 HP-UX ia64-*-hpux*
1207 Analog Devices, Inc. Blackfin Processor bfin-*
1209 * Ada task switching is now supported on sparc-elf targets when
1210 debugging a program using the Ravenscar Profile. For more information,
1211 see the "Tasking Support when using the Ravenscar Profile" section
1212 in the GDB user manual.
1214 * Guile support was removed.
1216 * New features in the GNU simulator
1218 ** The --map-info flag lists all known core mappings.
1220 ** CFI flashes may be simulated via the "cfi" device.
1222 *** Changes in GDB 7.2
1224 * Shared library support for remote targets by default
1226 When GDB is configured for a generic, non-OS specific target, like
1227 for example, --target=arm-eabi or one of the many *-*-elf targets,
1228 GDB now queries remote stubs for loaded shared libraries using the
1229 `qXfer:libraries:read' packet. Previously, shared library support
1230 was always disabled for such configurations.
1234 ** Argument Dependent Lookup (ADL)
1236 In C++ ADL lookup directs function search to the namespaces of its
1237 arguments even if the namespace has not been imported.
1247 Here the compiler will search for `foo' in the namespace of 'b'
1248 and find A::foo. GDB now supports this. This construct is commonly
1249 used in the Standard Template Library for operators.
1251 ** Improved User Defined Operator Support
1253 In addition to member operators, GDB now supports lookup of operators
1254 defined in a namespace and imported with a `using' directive, operators
1255 defined in the global scope, operators imported implicitly from an
1256 anonymous namespace, and the ADL operators mentioned in the previous
1258 GDB now also supports proper overload resolution for all the previously
1259 mentioned flavors of operators.
1261 ** static const class members
1263 Printing of static const class members that are initialized in the
1264 class definition has been fixed.
1266 * Windows Thread Information Block access.
1268 On Windows targets, GDB now supports displaying the Windows Thread
1269 Information Block (TIB) structure. This structure is visible either
1270 by using the new command `info w32 thread-information-block' or, by
1271 dereferencing the new convenience variable named `$_tlb', a
1272 thread-specific pointer to the TIB. This feature is also supported
1273 when remote debugging using GDBserver.
1275 * Static tracepoints
1277 Static tracepoints are calls in the user program into a tracing
1278 library. One such library is a port of the LTTng kernel tracer to
1279 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1280 When debugging with GDBserver, GDB now supports combining the GDB
1281 tracepoint machinery with such libraries. For example: the user can
1282 use GDB to probe a static tracepoint marker (a call from the user
1283 program into the tracing library) with the new "strace" command (see
1284 "New commands" below). This creates a "static tracepoint" in the
1285 breakpoint list, that can be manipulated with the same feature set
1286 as fast and regular tracepoints. E.g., collect registers, local and
1287 global variables, collect trace state variables, and define
1288 tracepoint conditions. In addition, the user can collect extra
1289 static tracepoint marker specific data, by collecting the new
1290 $_sdata internal variable. When analyzing the trace buffer, you can
1291 inspect $_sdata like any other variable available to GDB. For more
1292 information, see the "Tracepoints" chapter in GDB user manual. New
1293 remote packets have been defined to support static tracepoints, see
1294 the "New remote packets" section below.
1296 * Better reconstruction of tracepoints after disconnected tracing
1298 GDB will attempt to download the original source form of tracepoint
1299 definitions when starting a trace run, and then will upload these
1300 upon reconnection to the target, resulting in a more accurate
1301 reconstruction of the tracepoints that are in use on the target.
1305 You can now exercise direct control over the ways that GDB can
1306 affect your program. For instance, you can disallow the setting of
1307 breakpoints, so that the program can run continuously (assuming
1308 non-stop mode). In addition, the "observer" variable is available
1309 to switch all of the different controls; in observer mode, GDB
1310 cannot affect the target's behavior at all, which is useful for
1311 tasks like diagnosing live systems in the field.
1313 * The new convenience variable $_thread holds the number of the
1316 * New remote packets
1320 Return the address of the Windows Thread Information Block of a given thread.
1324 In response to several of the tracepoint packets, the target may now
1325 also respond with a number of intermediate `qRelocInsn' request
1326 packets before the final result packet, to have GDB handle
1327 relocating an instruction to execute at a different address. This
1328 is particularly useful for stubs that support fast tracepoints. GDB
1329 reports support for this feature in the qSupported packet.
1333 List static tracepoint markers in the target program.
1337 List static tracepoint markers at a given address in the target
1340 qXfer:statictrace:read
1342 Read the static trace data collected (by a `collect $_sdata'
1343 tracepoint action). The remote stub reports support for this packet
1344 to gdb's qSupported query.
1348 Send the current settings of GDB's permission flags.
1352 Send part of the source (textual) form of a tracepoint definition,
1353 which includes location, conditional, and action list.
1355 * The source command now accepts a -s option to force searching for the
1356 script in the source search path even if the script name specifies
1359 * New features in the GDB remote stub, GDBserver
1361 - GDBserver now support tracepoints (including fast tracepoints, and
1362 static tracepoints). The feature is currently supported by the
1363 i386-linux and amd64-linux builds. See the "Tracepoints support
1364 in gdbserver" section in the manual for more information.
1366 GDBserver JIT compiles the tracepoint's conditional agent
1367 expression bytecode into native code whenever possible for low
1368 overhead dynamic tracepoints conditionals. For such tracepoints,
1369 an expression that examines program state is evaluated when the
1370 tracepoint is reached, in order to determine whether to capture
1371 trace data. If the condition is simple and false, processing the
1372 tracepoint finishes very quickly and no data is gathered.
1374 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1375 for static tracepoints support.
1377 - GDBserver now supports x86_64 Windows 64-bit debugging.
1379 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1380 it understands register description.
1382 * The --batch flag now disables pagination and queries.
1384 * X86 general purpose registers
1386 GDB now supports reading/writing byte, word and double-word x86
1387 general purpose registers directly. This means you can use, say,
1388 $ah or $ax to refer, respectively, to the byte register AH and
1389 16-bit word register AX that are actually portions of the 32-bit
1390 register EAX or 64-bit register RAX.
1392 * The `commands' command now accepts a range of breakpoints to modify.
1393 A plain `commands' following a command that creates multiple
1394 breakpoints affects all the breakpoints set by that command. This
1395 applies to breakpoints set by `rbreak', and also applies when a
1396 single `break' command creates multiple breakpoints (e.g.,
1397 breakpoints on overloaded c++ functions).
1399 * The `rbreak' command now accepts a filename specification as part of
1400 its argument, limiting the functions selected by the regex to those
1401 in the specified file.
1403 * Support for remote debugging Windows and SymbianOS shared libraries
1404 from Unix hosts has been improved. Non Windows GDB builds now can
1405 understand target reported file names that follow MS-DOS based file
1406 system semantics, such as file names that include drive letters and
1407 use the backslash character as directory separator. This makes it
1408 possible to transparently use the "set sysroot" and "set
1409 solib-search-path" on Unix hosts to point as host copies of the
1410 target's shared libraries. See the new command "set
1411 target-file-system-kind" described below, and the "Commands to
1412 specify files" section in the user manual for more information.
1416 eval template, expressions...
1417 Convert the values of one or more expressions under the control
1418 of the string template to a command line, and call it.
1420 set target-file-system-kind unix|dos-based|auto
1421 show target-file-system-kind
1422 Set or show the assumed file system kind for target reported file
1425 save breakpoints <filename>
1426 Save all current breakpoint definitions to a file suitable for use
1427 in a later debugging session. To read the saved breakpoint
1428 definitions, use the `source' command.
1430 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1433 info static-tracepoint-markers
1434 Display information about static tracepoint markers in the target.
1436 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1437 Define a static tracepoint by probing a marker at the given
1438 function, line, address, or marker ID.
1442 Enable and disable observer mode.
1444 set may-write-registers on|off
1445 set may-write-memory on|off
1446 set may-insert-breakpoints on|off
1447 set may-insert-tracepoints on|off
1448 set may-insert-fast-tracepoints on|off
1449 set may-interrupt on|off
1450 Set individual permissions for GDB effects on the target. Note that
1451 some of these settings can have undesirable or surprising
1452 consequences, particularly when changed in the middle of a session.
1453 For instance, disabling the writing of memory can prevent
1454 breakpoints from being inserted, cause single-stepping to fail, or
1455 even crash your program, if you disable after breakpoints have been
1456 inserted. However, GDB should not crash.
1458 set record memory-query on|off
1459 show record memory-query
1460 Control whether to stop the inferior if memory changes caused
1461 by an instruction cannot be recorded.
1466 The disassemble command now supports "start,+length" form of two arguments.
1470 ** GDB now provides a new directory location, called the python directory,
1471 where Python scripts written for GDB can be installed. The location
1472 of that directory is <data-directory>/python, where <data-directory>
1473 is the GDB data directory. For more details, see section `Scripting
1474 GDB using Python' in the manual.
1476 ** The GDB Python API now has access to breakpoints, symbols, symbol
1477 tables, program spaces, inferiors, threads and frame's code blocks.
1478 Additionally, GDB Parameters can now be created from the API, and
1479 manipulated via set/show in the CLI.
1481 ** New functions gdb.target_charset, gdb.target_wide_charset,
1482 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1484 ** New exception gdb.GdbError.
1486 ** Pretty-printers are now also looked up in the current program space.
1488 ** Pretty-printers can now be individually enabled and disabled.
1490 ** GDB now looks for names of Python scripts to auto-load in a
1491 special section named `.debug_gdb_scripts', in addition to looking
1492 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1494 * Tracepoint actions were unified with breakpoint commands. In particular,
1495 there are no longer differences in "info break" output for breakpoints and
1496 tracepoints and the "commands" command can be used for both tracepoints and
1497 regular breakpoints.
1501 ARM Symbian arm*-*-symbianelf*
1503 * D language support.
1504 GDB now supports debugging programs written in the D programming
1507 * GDB now supports the extended ptrace interface for PowerPC which is
1508 available since Linux kernel version 2.6.34. This automatically enables
1509 any hardware breakpoints and additional hardware watchpoints available in
1510 the processor. The old ptrace interface exposes just one hardware
1511 watchpoint and no hardware breakpoints.
1513 * GDB is now able to use the Data Value Compare (DVC) register available on
1514 embedded PowerPC processors to implement in hardware simple watchpoint
1515 conditions of the form:
1517 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1519 This works in native GDB running on Linux kernels with the extended ptrace
1520 interface mentioned above.
1522 *** Changes in GDB 7.1
1526 ** Namespace Support
1528 GDB now supports importing of namespaces in C++. This enables the
1529 user to inspect variables from imported namespaces. Support for
1530 namepace aliasing has also been added. So, if a namespace is
1531 aliased in the current scope (e.g. namepace C=A; ) the user can
1532 print variables using the alias (e.g. (gdb) print C::x).
1536 All known bugs relating to the printing of virtual base class were
1537 fixed. It is now possible to call overloaded static methods using a
1542 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1543 and reinterpret_cast<> are now handled by the C++ expression parser.
1547 Xilinx MicroBlaze microblaze-*-*
1552 Xilinx MicroBlaze microblaze
1555 * Multi-program debugging.
1557 GDB now has support for multi-program (a.k.a. multi-executable or
1558 multi-exec) debugging. This allows for debugging multiple inferiors
1559 simultaneously each running a different program under the same GDB
1560 session. See "Debugging Multiple Inferiors and Programs" in the
1561 manual for more information. This implied some user visible changes
1562 in the multi-inferior support. For example, "info inferiors" now
1563 lists inferiors that are not running yet or that have exited
1564 already. See also "New commands" and "New options" below.
1566 * New tracing features
1568 GDB's tracepoint facility now includes several new features:
1570 ** Trace state variables
1572 GDB tracepoints now include support for trace state variables, which
1573 are variables managed by the target agent during a tracing
1574 experiment. They are useful for tracepoints that trigger each
1575 other, so for instance one tracepoint can count hits in a variable,
1576 and then a second tracepoint has a condition that is true when the
1577 count reaches a particular value. Trace state variables share the
1578 $-syntax of GDB convenience variables, and can appear in both
1579 tracepoint actions and condition expressions. Use the "tvariable"
1580 command to create, and "info tvariables" to view; see "Trace State
1581 Variables" in the manual for more detail.
1585 GDB now includes an option for defining fast tracepoints, which
1586 targets may implement more efficiently, such as by installing a jump
1587 into the target agent rather than a trap instruction. The resulting
1588 speedup can be by two orders of magnitude or more, although the
1589 tradeoff is that some program locations on some target architectures
1590 might not allow fast tracepoint installation, for instance if the
1591 instruction to be replaced is shorter than the jump. To request a
1592 fast tracepoint, use the "ftrace" command, with syntax identical to
1593 the regular trace command.
1595 ** Disconnected tracing
1597 It is now possible to detach GDB from the target while it is running
1598 a trace experiment, then reconnect later to see how the experiment
1599 is going. In addition, a new variable disconnected-tracing lets you
1600 tell the target agent whether to continue running a trace if the
1601 connection is lost unexpectedly.
1605 GDB now has the ability to save the trace buffer into a file, and
1606 then use that file as a target, similarly to you can do with
1607 corefiles. You can select trace frames, print data that was
1608 collected in them, and use tstatus to display the state of the
1609 tracing run at the moment that it was saved. To create a trace
1610 file, use "tsave <filename>", and to use it, do "target tfile
1613 ** Circular trace buffer
1615 You can ask the target agent to handle the trace buffer as a
1616 circular buffer, discarding the oldest trace frames to make room for
1617 newer ones, by setting circular-trace-buffer to on. This feature may
1618 not be available for all target agents.
1623 The disassemble command, when invoked with two arguments, now requires
1624 the arguments to be comma-separated.
1627 The info variables command now displays variable definitions. Files
1628 which only declare a variable are not shown.
1631 The source command is now capable of sourcing Python scripts.
1632 This feature is dependent on the debugger being build with Python
1635 Related to this enhancement is also the introduction of a new command
1636 "set script-extension" (see below).
1638 * New commands (for set/show, see "New options" below)
1640 record save [<FILENAME>]
1641 Save a file (in core file format) containing the process record
1642 execution log for replay debugging at a later time.
1644 record restore <FILENAME>
1645 Restore the process record execution log that was saved at an
1646 earlier time, for replay debugging.
1648 add-inferior [-copies <N>] [-exec <FILENAME>]
1651 clone-inferior [-copies <N>] [ID]
1652 Make a new inferior ready to execute the same program another
1653 inferior has loaded.
1658 maint info program-spaces
1659 List the program spaces loaded into GDB.
1661 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1662 show remote interrupt-sequence
1663 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1664 as the sequence to the remote target in order to interrupt the execution.
1665 Ctrl-C is a default. Some system prefers BREAK which is high level of
1666 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1667 Magic SysRq g. It is BREAK signal and character 'g'.
1669 set remote interrupt-on-connect [on | off]
1670 show remote interrupt-on-connect
1671 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1672 remote target when gdb connects to it. This is needed when you debug
1675 set remotebreak [on | off]
1677 Deprecated. Use "set/show remote interrupt-sequence" instead.
1679 tvariable $NAME [ = EXP ]
1680 Create or modify a trace state variable.
1683 List trace state variables and their values.
1685 delete tvariable $NAME ...
1686 Delete one or more trace state variables.
1689 Evaluate the given expressions without collecting anything into the
1690 trace buffer. (Valid in tracepoint actions only.)
1692 ftrace FN / FILE:LINE / *ADDR
1693 Define a fast tracepoint at the given function, line, or address.
1695 * New expression syntax
1697 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1698 GDB now parses 0b101010 identically with 42.
1702 set follow-exec-mode new|same
1703 show follow-exec-mode
1704 Control whether GDB reuses the same inferior across an exec call or
1705 creates a new one. This is useful to be able to restart the old
1706 executable after the inferior having done an exec call.
1708 set default-collect EXPR, ...
1709 show default-collect
1710 Define a list of expressions to be collected at each tracepoint.
1711 This is a useful way to ensure essential items are not overlooked,
1712 such as registers or a critical global variable.
1714 set disconnected-tracing
1715 show disconnected-tracing
1716 If set to 1, the target is instructed to continue tracing if it
1717 loses its connection to GDB. If 0, the target is to stop tracing
1720 set circular-trace-buffer
1721 show circular-trace-buffer
1722 If set to on, the target is instructed to use a circular trace buffer
1723 and discard the oldest trace frames instead of stopping the trace due
1724 to a full trace buffer. If set to off, the trace stops when the buffer
1725 fills up. Some targets may not support this.
1727 set script-extension off|soft|strict
1728 show script-extension
1729 If set to "off", the debugger does not perform any script language
1730 recognition, and all sourced files are assumed to be GDB scripts.
1731 If set to "soft" (the default), files are sourced according to
1732 filename extension, falling back to GDB scripts if the first
1734 If set to "strict", files are sourced according to filename extension.
1736 set ada trust-PAD-over-XVS on|off
1737 show ada trust-PAD-over-XVS
1738 If off, activate a workaround against a bug in the debugging information
1739 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1740 the GCC sources for more information about the GNAT encoding and
1741 PAD types in particular). It is always safe to set this option to
1742 off, but this introduces a slight performance penalty. The default
1745 * Python API Improvements
1747 ** GDB provides the new class gdb.LazyString. This is useful in
1748 some pretty-printing cases. The new method gdb.Value.lazy_string
1749 provides a simple way to create objects of this type.
1751 ** The fields returned by gdb.Type.fields now have an
1752 `is_base_class' attribute.
1754 ** The new method gdb.Type.range returns the range of an array type.
1756 ** The new method gdb.parse_and_eval can be used to parse and
1757 evaluate an expression.
1759 * New remote packets
1762 Define a trace state variable.
1765 Get the current value of a trace state variable.
1768 Set desired tracing behavior upon disconnection.
1771 Set the trace buffer to be linear or circular.
1774 Get data about the tracepoints currently in use.
1778 Process record now works correctly with hardware watchpoints.
1780 Multiple bug fixes have been made to the mips-irix port, making it
1781 much more reliable. In particular:
1782 - Debugging threaded applications is now possible again. Previously,
1783 GDB would hang while starting the program, or while waiting for
1784 the program to stop at a breakpoint.
1785 - Attaching to a running process no longer hangs.
1786 - An error occurring while loading a core file has been fixed.
1787 - Changing the value of the PC register now works again. This fixes
1788 problems observed when using the "jump" command, or when calling
1789 a function from GDB, or even when assigning a new value to $pc.
1790 - With the "finish" and "return" commands, the return value for functions
1791 returning a small array is now correctly printed.
1792 - It is now possible to break on shared library code which gets executed
1793 during a shared library init phase (code executed while executing
1794 their .init section). Previously, the breakpoint would have no effect.
1795 - GDB is now able to backtrace through the signal handler for
1796 non-threaded programs.
1798 PIE (Position Independent Executable) programs debugging is now supported.
1799 This includes debugging execution of PIC (Position Independent Code) shared
1800 libraries although for that, it should be possible to run such libraries as an
1803 *** Changes in GDB 7.0
1805 * GDB now has an interface for JIT compilation. Applications that
1806 dynamically generate code can create symbol files in memory and register
1807 them with GDB. For users, the feature should work transparently, and
1808 for JIT developers, the interface is documented in the GDB manual in the
1809 "JIT Compilation Interface" chapter.
1811 * Tracepoints may now be conditional. The syntax is as for
1812 breakpoints; either an "if" clause appended to the "trace" command,
1813 or the "condition" command is available. GDB sends the condition to
1814 the target for evaluation using the same bytecode format as is used
1815 for tracepoint actions.
1817 * The disassemble command now supports: an optional /r modifier, print the
1818 raw instructions in hex as well as in symbolic form, and an optional /m
1819 modifier to print mixed source+assembly.
1821 * Process record and replay
1823 In a architecture environment that supports ``process record and
1824 replay'', ``process record and replay'' target can record a log of
1825 the process execution, and replay it with both forward and reverse
1828 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1829 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1830 set execution-direction {forward|reverse}, for targets that support
1833 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1834 feature is available with a native GDB running on kernel version
1837 * GDB now has support for multi-byte and wide character sets on the
1838 target. Strings whose character type is wchar_t, char16_t, or
1839 char32_t are now correctly printed. GDB supports wide- and unicode-
1840 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1841 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1842 `printf'. This feature requires iconv to work properly; if your
1843 system does not have a working iconv, GDB can use GNU libiconv. See
1844 the installation instructions for more information.
1846 * GDB now supports automatic retrieval of shared library files from
1847 remote targets. To use this feature, specify a system root that begins
1848 with the `remote:' prefix, either via the `set sysroot' command or via
1849 the `--with-sysroot' configure-time option.
1851 * "info sharedlibrary" now takes an optional regex of libraries to show,
1852 and it now reports if a shared library has no debugging information.
1854 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1855 now complete on file names.
1857 * When completing in expressions, gdb will attempt to limit
1858 completions to allowable structure or union fields, where appropriate.
1859 For instance, consider:
1861 # struct example { int f1; double f2; };
1862 # struct example variable;
1865 If the user types TAB at the end of this command line, the available
1866 completions will be "f1" and "f2".
1868 * Inlined functions are now supported. They show up in backtraces, and
1869 the "step", "next", and "finish" commands handle them automatically.
1871 * GDB now supports the token-splicing (##) and stringification (#)
1872 operators when expanding macros. It also supports variable-arity
1875 * GDB now supports inspecting extra signal information, exported by
1876 the new $_siginfo convenience variable. The feature is currently
1877 implemented on linux ARM, i386 and amd64.
1879 * GDB can now display the VFP floating point registers and NEON vector
1880 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1881 can provide these registers (requires Linux 2.6.30 or later). Remote
1882 and simulator targets may also provide them.
1884 * New remote packets
1887 Search memory for a sequence of bytes.
1890 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1891 operation over reliable transport links. Use of this packet is
1892 controlled by the `set remote noack-packet' command.
1895 Kill the process with the specified process ID. Use this in preference
1896 to `k' when multiprocess protocol extensions are supported.
1899 Obtains additional operating system information
1903 Read or write additional signal information.
1905 * Removed remote protocol undocumented extension
1907 An undocumented extension to the remote protocol's `S' stop reply
1908 packet that permited the stub to pass a process id was removed.
1909 Remote servers should use the `T' stop reply packet instead.
1911 * GDB now supports multiple function calling conventions according to the
1912 DWARF-2 DW_AT_calling_convention function attribute.
1914 * The SH target utilizes the aforementioned change to distinguish between gcc
1915 and Renesas calling convention. It also adds the new CLI commands
1916 `set/show sh calling-convention'.
1918 * GDB can now read compressed debug sections, as produced by GNU gold
1919 with the --compress-debug-sections=zlib flag.
1921 * 64-bit core files are now supported on AIX.
1923 * Thread switching is now supported on Tru64.
1925 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1926 which will be allocated using malloc later in program execution.
1928 * The qXfer:libraries:read remote procotol packet now allows passing a
1929 list of section offsets.
1931 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1932 conditions handling signals delivered during attach or thread creation
1933 have also been fixed.
1935 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1936 From the user's standpoint, all unqualified instances of True and False
1937 are treated as the standard definitions, regardless of context.
1939 * GDB now parses C++ symbol and type names more flexibly. For
1942 template<typename T> class C { };
1945 GDB will now correctly handle all of:
1947 ptype C<char const *>
1948 ptype C<char const*>
1949 ptype C<const char *>
1950 ptype C<const char*>
1952 * New features in the GDB remote stub, gdbserver
1954 - The "--wrapper" command-line argument tells gdbserver to use a
1955 wrapper program to launch programs for debugging.
1957 - On PowerPC and S/390 targets, it is now possible to use a single
1958 gdbserver executable to debug both 32-bit and 64-bit programs.
1959 (This requires gdbserver itself to be built as a 64-bit executable.)
1961 - gdbserver uses the new noack protocol mode for TCP connections to
1962 reduce communications latency, if also supported and enabled in GDB.
1964 - Support for the sparc64-linux-gnu target is now included in
1967 - The amd64-linux build of gdbserver now supports debugging both
1968 32-bit and 64-bit programs.
1970 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1971 now support hardware watchpoints, and will use them automatically
1976 GDB now has support for scripting using Python. Whether this is
1977 available is determined at configure time.
1979 New GDB commands can now be written in Python.
1981 * Ada tasking support
1983 Ada tasks can now be inspected in GDB. The following commands have
1987 Print the list of Ada tasks.
1989 Print detailed information about task number N.
1991 Print the task number of the current task.
1993 Switch the context of debugging to task number N.
1995 * Support for user-defined prefixed commands. The "define" command can
1996 add new commands to existing prefixes, e.g. "target".
1998 * Multi-inferior, multi-process debugging.
2000 GDB now has generalized support for multi-inferior debugging. See
2001 "Debugging Multiple Inferiors" in the manual for more information.
2002 Although availability still depends on target support, the command
2003 set is more uniform now. The GNU/Linux specific multi-forks support
2004 has been migrated to this new framework. This implied some user
2005 visible changes; see "New commands" and also "Removed commands"
2008 * Target descriptions can now describe the target OS ABI. See the
2009 "Target Description Format" section in the user manual for more
2012 * Target descriptions can now describe "compatible" architectures
2013 to indicate that the target can execute applications for a different
2014 architecture in addition to those for the main target architecture.
2015 See the "Target Description Format" section in the user manual for
2018 * Multi-architecture debugging.
2020 GDB now includes general supports for debugging applications on
2021 hybrid systems that use more than one single processor architecture
2022 at the same time. Each such hybrid architecture still requires
2023 specific support to be added. The only hybrid architecture supported
2024 in this version of GDB is the Cell Broadband Engine.
2026 * GDB now supports integrated debugging of Cell/B.E. applications that
2027 use both the PPU and SPU architectures. To enable support for hybrid
2028 Cell/B.E. debugging, you need to configure GDB to support both the
2029 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2030 --enable-targets configure option.
2032 * Non-stop mode debugging.
2034 For some targets, GDB now supports an optional mode of operation in
2035 which you can examine stopped threads while other threads continue
2036 to execute freely. This is referred to as non-stop mode, with the
2037 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2038 section in the user manual for more information.
2040 To be able to support remote non-stop debugging, a remote stub needs
2041 to implement the non-stop mode remote protocol extensions, as
2042 described in the "Remote Non-Stop" section of the user manual. The
2043 GDB remote stub, gdbserver, has been adjusted to support these
2044 extensions on linux targets.
2046 * New commands (for set/show, see "New options" below)
2048 catch syscall [NAME(S) | NUMBER(S)]
2049 Catch system calls. Arguments, which should be names of system
2050 calls or their numbers, mean catch only those syscalls. Without
2051 arguments, every syscall will be caught. When the inferior issues
2052 any of the specified syscalls, GDB will stop and announce the system
2053 call, both when it is called and when its call returns. This
2054 feature is currently available with a native GDB running on the
2055 Linux Kernel, under the following architectures: x86, x86_64,
2056 PowerPC and PowerPC64.
2058 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2060 Search memory for a sequence of bytes.
2062 maint set python print-stack
2063 maint show python print-stack
2064 Show a stack trace when an error is encountered in a Python script.
2067 Invoke CODE by passing it to the Python interpreter.
2072 These allow macros to be defined, undefined, and listed
2076 Show operating system information about processes.
2079 List the inferiors currently under GDB's control.
2082 Switch focus to inferior number NUM.
2085 Detach from inferior number NUM.
2088 Kill inferior number NUM.
2092 set spu stop-on-load
2093 show spu stop-on-load
2094 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2096 set spu auto-flush-cache
2097 show spu auto-flush-cache
2098 Control whether to automatically flush the software-managed cache
2099 during Cell/B.E. debugging.
2101 set sh calling-convention
2102 show sh calling-convention
2103 Control the calling convention used when calling SH target functions.
2106 show debug timestamp
2107 Control display of timestamps with GDB debugging output.
2109 set disassemble-next-line
2110 show disassemble-next-line
2111 Control display of disassembled source lines or instructions when
2114 set remote noack-packet
2115 show remote noack-packet
2116 Set/show the use of remote protocol QStartNoAckMode packet. See above
2117 under "New remote packets."
2119 set remote query-attached-packet
2120 show remote query-attached-packet
2121 Control use of remote protocol `qAttached' (query-attached) packet.
2123 set remote read-siginfo-object
2124 show remote read-siginfo-object
2125 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2128 set remote write-siginfo-object
2129 show remote write-siginfo-object
2130 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2133 set remote reverse-continue
2134 show remote reverse-continue
2135 Control use of remote protocol 'bc' (reverse-continue) packet.
2137 set remote reverse-step
2138 show remote reverse-step
2139 Control use of remote protocol 'bs' (reverse-step) packet.
2141 set displaced-stepping
2142 show displaced-stepping
2143 Control displaced stepping mode. Displaced stepping is a way to
2144 single-step over breakpoints without removing them from the debuggee.
2145 Also known as "out-of-line single-stepping".
2148 show debug displaced
2149 Control display of debugging info for displaced stepping.
2151 maint set internal-error
2152 maint show internal-error
2153 Control what GDB does when an internal error is detected.
2155 maint set internal-warning
2156 maint show internal-warning
2157 Control what GDB does when an internal warning is detected.
2162 Use a wrapper program to launch programs for debugging.
2164 set multiple-symbols (all|ask|cancel)
2165 show multiple-symbols
2166 The value of this variable can be changed to adjust the debugger behavior
2167 when an expression or a breakpoint location contains an ambiguous symbol
2168 name (an overloaded function name, for instance).
2170 set breakpoint always-inserted
2171 show breakpoint always-inserted
2172 Keep breakpoints always inserted in the target, as opposed to inserting
2173 them when resuming the target, and removing them when the target stops.
2174 This option can improve debugger performance on slow remote targets.
2176 set arm fallback-mode (arm|thumb|auto)
2177 show arm fallback-mode
2178 set arm force-mode (arm|thumb|auto)
2180 These commands control how ARM GDB determines whether instructions
2181 are ARM or Thumb. The default for both settings is auto, which uses
2182 the current CPSR value for instructions without symbols; previous
2183 versions of GDB behaved as if "set arm fallback-mode arm".
2185 set disable-randomization
2186 show disable-randomization
2187 Standalone programs run with the virtual address space randomization enabled
2188 by default on some platforms. This option keeps the addresses stable across
2189 multiple debugging sessions.
2193 Control whether other threads are stopped or not when some thread hits
2198 Requests that asynchronous execution is enabled in the target, if available.
2199 In this case, it's possible to resume target in the background, and interact
2200 with GDB while the target is running. "show target-async" displays the
2201 current state of asynchronous execution of the target.
2203 set target-wide-charset
2204 show target-wide-charset
2205 The target-wide-charset is the name of the character set that GDB
2206 uses when printing characters whose type is wchar_t.
2208 set tcp auto-retry (on|off)
2210 set tcp connect-timeout
2211 show tcp connect-timeout
2212 These commands allow GDB to retry failed TCP connections to a remote stub
2213 with a specified timeout period; this is useful if the stub is launched
2214 in parallel with GDB but may not be ready to accept connections immediately.
2216 set libthread-db-search-path
2217 show libthread-db-search-path
2218 Control list of directories which GDB will search for appropriate
2221 set schedule-multiple (on|off)
2222 show schedule-multiple
2223 Allow GDB to resume all threads of all processes or only threads of
2224 the current process.
2228 Use more aggressive caching for accesses to the stack. This improves
2229 performance of remote debugging (particularly backtraces) without
2230 affecting correctness.
2232 set interactive-mode (on|off|auto)
2233 show interactive-mode
2234 Control whether GDB runs in interactive mode (on) or not (off).
2235 When in interactive mode, GDB waits for the user to answer all
2236 queries. Otherwise, GDB does not wait and assumes the default
2237 answer. When set to auto (the default), GDB determines which
2238 mode to use based on the stdin settings.
2243 For program forks, this is replaced by the new more generic `info
2244 inferiors' command. To list checkpoints, you can still use the
2245 `info checkpoints' command, which was an alias for the `info forks'
2249 Replaced by the new `inferior' command. To switch between
2250 checkpoints, you can still use the `restart' command, which was an
2251 alias for the `fork' command.
2254 This is removed, since some targets don't have a notion of
2255 processes. To switch between processes, you can still use the
2256 `inferior' command using GDB's own inferior number.
2259 For program forks, this is replaced by the new more generic `kill
2260 inferior' command. To delete a checkpoint, you can still use the
2261 `delete checkpoint' command, which was an alias for the `delete
2265 For program forks, this is replaced by the new more generic `detach
2266 inferior' command. To detach a checkpoint, you can still use the
2267 `detach checkpoint' command, which was an alias for the `detach
2270 * New native configurations
2272 x86/x86_64 Darwin i[34567]86-*-darwin*
2274 x86_64 MinGW x86_64-*-mingw*
2278 Lattice Mico32 lm32-*
2279 x86 DICOS i[34567]86-*-dicos*
2280 x86_64 DICOS x86_64-*-dicos*
2283 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2284 (mingw32ce) debugging.
2290 These commands were actually not implemented on any target.
2292 *** Changes in GDB 6.8
2294 * New native configurations
2296 NetBSD/hppa hppa*-*netbsd*
2297 Xtensa GNU/Linux xtensa*-*-linux*
2301 NetBSD/hppa hppa*-*-netbsd*
2302 Xtensa GNU/Lunux xtensa*-*-linux*
2304 * Change in command line behavior -- corefiles vs. process ids.
2306 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2307 attaching to process NUMBER fails, GDB no longer attempts to open a
2308 core file named NUMBER. Attaching to a program using the -c option
2309 is no longer supported. Instead, use the '-p' or '--pid' options.
2311 * GDB can now be built as a native debugger for debugging Windows x86
2312 (mingw32) Portable Executable (PE) programs.
2314 * Pending breakpoints no longer change their number when their address
2317 * GDB now supports breakpoints with multiple locations,
2318 including breakpoints on C++ constructors, inside C++ templates,
2319 and in inlined functions.
2321 * GDB's ability to debug optimized code has been improved. GDB more
2322 accurately identifies function bodies and lexical blocks that occupy
2323 more than one contiguous range of addresses.
2325 * Target descriptions can now describe registers for PowerPC.
2327 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2328 registers on PowerPC targets.
2330 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2331 targets even when the libthread_db library is not available.
2333 * The GDB remote stub, gdbserver, now supports the new file transfer
2334 commands (remote put, remote get, and remote delete).
2336 * The GDB remote stub, gdbserver, now supports run and attach in
2337 extended-remote mode.
2339 * hppa*64*-*-hpux11* target broken
2340 The debugger is unable to start a program and fails with the following
2341 error: "Error trying to get information about dynamic linker".
2342 The gdb-6.7 release is also affected.
2344 * GDB now supports the --enable-targets= configure option to allow
2345 building a single GDB executable that supports multiple remote
2346 target architectures.
2348 * GDB now supports debugging C and C++ programs which use the
2349 Decimal Floating Point extension. In addition, the PowerPC target
2350 now has a set of pseudo-registers to inspect decimal float values
2351 stored in two consecutive float registers.
2353 * The -break-insert MI command can optionally create pending
2356 * Improved support for debugging Ada
2357 Many improvements to the Ada language support have been made. These
2359 - Better support for Ada2005 interface types
2360 - Improved handling of arrays and slices in general
2361 - Better support for Taft-amendment types
2362 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2364 - Improved command completion in Ada
2367 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2372 set print frame-arguments (all|scalars|none)
2373 show print frame-arguments
2374 The value of this variable can be changed to control which argument
2375 values should be printed by the debugger when displaying a frame.
2380 Transfer files to and from a remote target, and delete remote files.
2387 Transfer files to and from a remote target, and delete remote files.
2389 * New remote packets
2396 Open, close, read, write, and delete files on the remote system.
2399 Attach to an existing process on the remote system, in extended-remote
2403 Run a new process on the remote system, in extended-remote mode.
2405 *** Changes in GDB 6.7
2407 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2408 bfd, libiberty and opcodes, as revealed by static analysis donated by
2409 Coverity, Inc. (http://scan.coverity.com).
2411 * When looking up multiply-defined global symbols, GDB will now prefer the
2412 symbol definition in the current shared library if it was built using the
2413 -Bsymbolic linker option.
2415 * When the Text User Interface (TUI) is not configured, GDB will now
2416 recognize the -tui command-line option and print a message that the TUI
2419 * The GDB remote stub, gdbserver, now has lower overhead for high
2420 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2422 * GDB for MIPS targets now autodetects whether a remote target provides
2423 32-bit or 64-bit register values.
2425 * Support for C++ member pointers has been improved.
2427 * GDB now understands XML target descriptions, which specify the
2428 target's overall architecture. GDB can read a description from
2429 a local file or over the remote serial protocol.
2431 * Vectors of single-byte data use a new integer type which is not
2432 automatically displayed as character or string data.
2434 * The /s format now works with the print command. It displays
2435 arrays of single-byte integers and pointers to single-byte integers
2438 * Target descriptions can now describe target-specific registers,
2439 for architectures which have implemented the support (currently
2440 only ARM, M68K, and MIPS).
2442 * GDB and the GDB remote stub, gdbserver, now support the XScale
2445 * The GDB remote stub, gdbserver, has been updated to support
2446 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2447 has been rewritten to use the standard GDB remote protocol.
2449 * GDB can now step into C++ functions which are called through thunks.
2451 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2453 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2454 layout. It also supports a TextSeg= and DataSeg= response when only
2455 segment base addresses (rather than offsets) are available.
2457 * The /i format now outputs any trailing branch delay slot instructions
2458 immediately following the last instruction within the count specified.
2460 * The GDB remote protocol "T" stop reply packet now supports a
2461 "library" response. Combined with the new "qXfer:libraries:read"
2462 packet, this response allows GDB to debug shared libraries on targets
2463 where the operating system manages the list of loaded libraries (e.g.
2464 Windows and SymbianOS).
2466 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2467 (DLLs) on Windows and Windows CE targets.
2469 * GDB now supports a faster verification that a .debug file matches its binary
2470 according to its build-id signature, if the signature is present.
2476 Enable or disable hardware flow control (RTS/CTS) on the serial port
2477 when debugging using remote targets.
2479 set mem inaccessible-by-default
2480 show mem inaccessible-by-default
2481 If the target supplies a memory map, for instance via the remote
2482 protocol's "qXfer:memory-map:read" packet, setting this variable
2483 prevents GDB from accessing memory outside the memory map. This
2484 is useful for targets with memory mapped registers or which react
2485 badly to accesses of unmapped address space.
2487 set breakpoint auto-hw
2488 show breakpoint auto-hw
2489 If the target supplies a memory map, for instance via the remote
2490 protocol's "qXfer:memory-map:read" packet, setting this variable
2491 lets GDB use hardware breakpoints automatically for memory regions
2492 where it can not use software breakpoints. This covers both the
2493 "break" command and internal breakpoints used for other commands
2494 including "next" and "finish".
2497 catch exception unhandled
2498 Stop the program execution when Ada exceptions are raised.
2501 Stop the program execution when an Ada assertion failed.
2505 Set an alternate system root for target files. This is a more
2506 general version of "set solib-absolute-prefix", which is now
2507 an alias to "set sysroot".
2510 Provide extended SPU facility status information. This set of
2511 commands is available only when debugging the Cell/B.E. SPU
2514 * New native configurations
2516 OpenBSD/sh sh*-*openbsd*
2519 unset tdesc filename
2521 Use the specified local file as an XML target description, and do
2522 not query the target for its built-in description.
2526 OpenBSD/sh sh*-*-openbsd*
2527 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2528 Toshiba Media Processor mep-elf
2530 * New remote packets
2533 Ignore the specified signals; pass them directly to the debugged program
2534 without stopping other threads or reporting them to GDB.
2536 qXfer:features:read:
2537 Read an XML target description from the target, which describes its
2542 Read or write contents of an spufs file on the target system. These
2543 packets are available only on the Cell/B.E. SPU architecture.
2545 qXfer:libraries:read:
2546 Report the loaded shared libraries. Combined with new "T" packet
2547 response, this packet allows GDB to debug shared libraries on
2548 targets where the operating system manages the list of loaded
2549 libraries (e.g. Windows and SymbianOS).
2553 Support for these obsolete configurations has been removed.
2561 i[34567]86-*-lynxos*
2562 i[34567]86-*-netware*
2563 i[34567]86-*-sco3.2v5*
2564 i[34567]86-*-sco3.2v4*
2566 i[34567]86-*-sysv4.2*
2569 i[34567]86-*-unixware2*
2570 i[34567]86-*-unixware*
2579 * Other removed features
2586 Various m68k-only ROM monitors.
2593 Various Renesas ROM monitors and debugging interfaces for SH and
2598 Support for a Macraigor serial interface to on-chip debugging.
2599 GDB does not directly support the newer parallel or USB
2604 A debug information format. The predecessor to DWARF 2 and
2605 DWARF 3, which are still supported.
2607 Support for the HP aCC compiler on HP-UX/PA-RISC
2609 SOM-encapsulated symbolic debugging information, automatic
2610 invocation of pxdb, and the aCC custom C++ ABI. This does not
2611 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2612 with aCC can still be debugged on an assembly level.
2614 MIPS ".pdr" sections
2616 A MIPS-specific format used to describe stack frame layout
2617 in debugging information.
2621 GDB could work with an older version of Guile to debug
2622 the interpreter and Scheme programs running in it.
2624 set mips stack-arg-size
2625 set mips saved-gpreg-size
2627 Use "set mips abi" to control parameter passing for MIPS.
2629 *** Changes in GDB 6.6
2634 Cell Broadband Engine SPU spu-elf
2636 * GDB can now be configured as a cross-debugger targeting native Windows
2637 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2638 running on a Windows system over TCP/IP to debug Windows programs.
2640 * The GDB remote stub, gdbserver, has been updated to support Windows and
2641 Cygwin debugging. Both single-threaded and multi-threaded programs are
2644 * The "set trust-readonly-sections" command works again. This command was
2645 broken in GDB 6.3, 6.4, and 6.5.
2647 * The "load" command now supports writing to flash memory, if the remote
2648 stub provides the required support.
2650 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2651 longer requires symbolic debug information (e.g. DWARF-2).
2656 unset substitute-path
2657 show substitute-path
2658 Manage a list of substitution rules that GDB uses to rewrite the name
2659 of the directories where the sources are located. This can be useful
2660 for instance when the sources were moved to a different location
2661 between compilation and debugging.
2665 Print each CLI command as it is executed. Each command is prefixed with
2666 a number of `+' symbols representing the nesting depth.
2667 The source command now has a `-v' option to enable the same feature.
2671 The ARM Demon monitor support (RDP protocol, "target rdp").
2673 Kernel Object Display, an embedded debugging feature which only worked with
2674 an obsolete version of Cisco IOS.
2676 The 'set download-write-size' and 'show download-write-size' commands.
2678 * New remote packets
2681 Tell a stub about GDB client features, and request remote target features.
2682 The first feature implemented is PacketSize, which allows the target to
2683 specify the size of packets it can handle - to minimize the number of
2684 packets required and improve performance when connected to a remote
2688 Fetch an OS auxilliary vector from the remote stub. This packet is a
2689 more efficient replacement for qPart:auxv:read.
2691 qXfer:memory-map:read:
2692 Fetch a memory map from the remote stub, including information about
2693 RAM, ROM, and flash memory devices.
2698 Erase and program a flash memory device.
2700 * Removed remote packets
2703 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2704 used it, and only gdbserver implemented it.
2706 *** Changes in GDB 6.5
2710 Renesas M32C/M16C m32c-elf
2712 Morpho Technologies ms1 ms1-elf
2716 init-if-undefined Initialize a convenience variable, but
2717 only if it doesn't already have a value.
2719 The following commands are presently only implemented for native GNU/Linux:
2721 checkpoint Save a snapshot of the program state.
2723 restart <n> Return the program state to a
2724 previously saved state.
2726 info checkpoints List currently saved checkpoints.
2728 delete-checkpoint <n> Delete a previously saved checkpoint.
2730 set|show detach-on-fork Tell gdb whether to detach from a newly
2731 forked process, or to keep debugging it.
2733 info forks List forks of the user program that
2734 are available to be debugged.
2736 fork <n> Switch to debugging one of several
2737 forks of the user program that are
2738 available to be debugged.
2740 delete-fork <n> Delete a fork from the list of forks
2741 that are available to be debugged (and
2742 kill the forked process).
2744 detach-fork <n> Delete a fork from the list of forks
2745 that are available to be debugged (and
2746 allow the process to continue).
2750 Morpho Technologies ms2 ms1-elf
2752 * Improved Windows host support
2754 GDB now builds as a cross debugger hosted on i686-mingw32, including
2755 native console support, and remote communications using either
2756 network sockets or serial ports.
2758 * Improved Modula-2 language support
2760 GDB can now print most types in the Modula-2 syntax. This includes:
2761 basic types, set types, record types, enumerated types, range types,
2762 pointer types and ARRAY types. Procedure var parameters are correctly
2763 printed and hexadecimal addresses and character constants are also
2764 written in the Modula-2 syntax. Best results can be obtained by using
2765 GNU Modula-2 together with the -gdwarf-2 command line option.
2769 The ARM rdi-share module.
2771 The Netware NLM debug server.
2773 *** Changes in GDB 6.4
2775 * New native configurations
2777 OpenBSD/arm arm*-*-openbsd*
2778 OpenBSD/mips64 mips64-*-openbsd*
2782 Morpho Technologies ms1 ms1-elf
2784 * New command line options
2786 --batch-silent As for --batch, but totally silent.
2787 --return-child-result The debugger will exist with the same value
2788 the child (debugged) program exited with.
2789 --eval-command COMMAND, -ex COMMAND
2790 Execute a single GDB CLI command. This may be
2791 specified multiple times and in conjunction
2792 with the --command (-x) option.
2794 * Deprecated commands removed
2796 The following commands, that were deprecated in 2000, have been
2800 set|show arm disassembly-flavor set|show arm disassembler
2801 othernames set arm disassembler
2802 set|show remotedebug set|show debug remote
2803 set|show archdebug set|show debug arch
2804 set|show eventdebug set|show debug event
2807 * New BSD user-level threads support
2809 It is now possible to debug programs using the user-level threads
2810 library on OpenBSD and FreeBSD. Currently supported (target)
2813 FreeBSD/amd64 x86_64-*-freebsd*
2814 FreeBSD/i386 i386-*-freebsd*
2815 OpenBSD/i386 i386-*-openbsd*
2817 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2818 are not yet supported.
2820 * New support for Matsushita MN10300 w/sim added
2821 (Work in progress). mn10300-elf.
2823 * REMOVED configurations and files
2825 VxWorks and the XDR protocol *-*-vxworks
2826 Motorola MCORE mcore-*-*
2827 National Semiconductor NS32000 ns32k-*-*
2829 * New "set print array-indexes" command
2831 After turning this setting "on", GDB prints the index of each element
2832 when displaying arrays. The default is "off" to preserve the previous
2835 * VAX floating point support
2837 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2839 * User-defined command support
2841 In addition to using $arg0..$arg9 for argument passing, it is now possible
2842 to use $argc to determine now many arguments have been passed. See the
2843 section on user-defined commands in the user manual for more information.
2845 *** Changes in GDB 6.3:
2847 * New command line option
2849 GDB now accepts -l followed by a number to set the timeout for remote
2852 * GDB works with GCC -feliminate-dwarf2-dups
2854 GDB now supports a more compact representation of DWARF-2 debug
2855 information using DW_FORM_ref_addr references. These are produced
2856 by GCC with the option -feliminate-dwarf2-dups and also by some
2857 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2858 to use -feliminate-dwarf2-dups.
2860 * Internationalization
2862 When supported by the host system, GDB will be built with
2863 internationalization (libintl). The task of marking up the sources is
2864 continued, we're looking forward to our first translation.
2868 Initial support for debugging programs compiled with the GNAT
2869 implementation of the Ada programming language has been integrated
2870 into GDB. In this release, support is limited to expression evaluation.
2872 * New native configurations
2874 GNU/Linux/m32r m32r-*-linux-gnu
2878 GDB's remote protocol now includes support for the 'p' packet. This
2879 packet is used to fetch individual registers from a remote inferior.
2881 * END-OF-LIFE registers[] compatibility module
2883 GDB's internal register infrastructure has been completely rewritten.
2884 The new infrastructure making possible the implementation of key new
2885 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2888 GDB 6.3 will be the last release to include the the registers[]
2889 compatibility module that allowed out-of-date configurations to
2890 continue to work. This change directly impacts the following
2900 powerpc bdm protocol
2902 Unless there is activity to revive these configurations, they will be
2903 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2905 * OBSOLETE configurations and files
2907 Configurations that have been declared obsolete in this release have
2908 been commented out. Unless there is activity to revive these
2909 configurations, the next release of GDB will have their sources
2910 permanently REMOVED.
2919 *** Changes in GDB 6.2.1:
2921 * MIPS `break main; run' gave an heuristic-fence-post warning
2923 When attempting to run even a simple program, a warning about
2924 heuristic-fence-post being hit would be reported. This problem has
2927 * MIPS IRIX 'long double' crashed GDB
2929 When examining a long double variable, GDB would get a segmentation
2930 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2931 IRIX long double values).
2935 A bug in the VAX stack code was causing problems with the "next"
2936 command. This problem has been fixed.
2938 *** Changes in GDB 6.2:
2940 * Fix for ``many threads''
2942 On GNU/Linux systems that use the NPTL threads library, a program
2943 rapidly creating and deleting threads would confuse GDB leading to the
2946 ptrace: No such process.
2947 thread_db_get_info: cannot get thread info: generic error
2949 This problem has been fixed.
2951 * "-async" and "-noasync" options removed.
2953 Support for the broken "-noasync" option has been removed (it caused
2956 * New ``start'' command.
2958 This command runs the program until the begining of the main procedure.
2960 * New BSD Kernel Data Access Library (libkvm) interface
2962 Using ``target kvm'' it is now possible to debug kernel core dumps and
2963 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2964 platforms. Currently supported (native-only) configurations are:
2966 FreeBSD/amd64 x86_64-*-freebsd*
2967 FreeBSD/i386 i?86-*-freebsd*
2968 NetBSD/i386 i?86-*-netbsd*
2969 NetBSD/m68k m68*-*-netbsd*
2970 NetBSD/sparc sparc-*-netbsd*
2971 OpenBSD/amd64 x86_64-*-openbsd*
2972 OpenBSD/i386 i?86-*-openbsd*
2973 OpenBSD/m68k m68*-openbsd*
2974 OpenBSD/sparc sparc-*-openbsd*
2976 * Signal trampoline code overhauled
2978 Many generic problems with GDB's signal handling code have been fixed.
2979 These include: backtraces through non-contiguous stacks; recognition
2980 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2981 call; backtrace through a signal trampoline; step into and out of
2982 signal handlers; and single-stepping in the signal trampoline.
2984 Please note that kernel bugs are a limiting factor here. These
2985 features have been shown to work on an s390 GNU/Linux system that
2986 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2988 * Cygwin support for DWARF 2 added.
2990 * New native configurations
2992 GNU/Linux/hppa hppa*-*-linux*
2993 OpenBSD/hppa hppa*-*-openbsd*
2994 OpenBSD/m68k m68*-*-openbsd*
2995 OpenBSD/m88k m88*-*-openbsd*
2996 OpenBSD/powerpc powerpc-*-openbsd*
2997 NetBSD/vax vax-*-netbsd*
2998 OpenBSD/vax vax-*-openbsd*
3000 * END-OF-LIFE frame compatibility module
3002 GDB's internal frame infrastructure has been completely rewritten.
3003 The new infrastructure making it possible to support key new features
3004 including DWARF 2 Call Frame Information. To aid in the task of
3005 migrating old configurations to this new infrastructure, a
3006 compatibility module, that allowed old configurations to continue to
3007 work, was also included.
3009 GDB 6.2 will be the last release to include this frame compatibility
3010 module. This change directly impacts the following configurations:
3020 Unless there is activity to revive these configurations, they will be
3021 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3023 * REMOVED configurations and files
3025 Sun 3, running SunOS 3 m68*-*-sunos3*
3026 Sun 3, running SunOS 4 m68*-*-sunos4*
3027 Sun 2, running SunOS 3 m68000-*-sunos3*
3028 Sun 2, running SunOS 4 m68000-*-sunos4*
3029 Motorola 680x0 running LynxOS m68*-*-lynxos*
3030 AT&T 3b1/Unix pc m68*-att-*
3031 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3032 decstation mips-dec-* mips-little-*
3033 riscos mips-*-riscos* mips-*-sysv*
3034 sonymips mips-sony-*
3035 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3037 *** Changes in GDB 6.1.1:
3039 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3041 The TUI (Text-mode User Interface) is now built as part of a default
3042 GDB configuration. It is enabled by either selecting the TUI with the
3043 command line option "-i=tui" or by running the separate "gdbtui"
3044 program. For more information on the TUI, see the manual "Debugging
3047 * Pending breakpoint support (also included in GDB 6.1)
3049 Support has been added to allow you to specify breakpoints in shared
3050 libraries that have not yet been loaded. If a breakpoint location
3051 cannot be found, and the "breakpoint pending" option is set to auto,
3052 GDB queries you if you wish to make the breakpoint pending on a future
3053 shared-library load. If and when GDB resolves the breakpoint symbol,
3054 the pending breakpoint is removed as one or more regular breakpoints
3057 Pending breakpoints are very useful for GCJ Java debugging.
3059 * Fixed ISO-C build problems
3061 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3062 non ISO-C code that stopped them being built using a more strict ISO-C
3063 compiler (e.g., IBM's C compiler).
3065 * Fixed build problem on IRIX 5
3067 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3068 wasn't able to compile compile on an IRIX 5 system.
3070 * Added execute permission to gdb/gdbserver/configure
3072 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3073 permission. This bug would cause configure to fail on a number of
3074 systems (Solaris, IRIX). Ref: server/519.
3076 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3078 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3079 has been updated to use constant array sizes.
3081 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3083 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3084 its generated DWARF Call Frame Info. This encoding was causing GDB to
3085 panic, that panic has been fixed. Ref: gdb/1628.
3087 * Fixed a problem when examining parameters in shared library code.
3089 When examining parameters in optimized shared library code generated
3090 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3091 not available''. GDB now correctly displays the variable's value.
3093 *** Changes in GDB 6.1:
3095 * Removed --with-mmalloc
3097 Support for the mmalloc memory manager has been removed, as it
3098 conflicted with the internal gdb byte cache.
3100 * Changes in AMD64 configurations
3102 The AMD64 target now includes the %cs and %ss registers. As a result
3103 the AMD64 remote protocol has changed; this affects the floating-point
3104 and SSE registers. If you rely on those registers for your debugging,
3105 you should upgrade gdbserver on the remote side.
3107 * Revised SPARC target
3109 The SPARC target has been completely revised, incorporating the
3110 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3111 support for LynxOS and SunOS 4 has been dropped. Calling functions
3112 from within GDB on operating systems with a non-executable stack
3113 (Solaris, OpenBSD) now works.
3117 GDB has a new C++ demangler which does a better job on the mangled
3118 names generated by current versions of g++. It also runs faster, so
3119 with this and other changes gdb should now start faster on large C++
3122 * DWARF 2 Location Expressions
3124 GDB support for location expressions has been extended to support function
3125 arguments and frame bases. Older versions of GDB could crash when they
3128 * C++ nested types and namespaces
3130 GDB's support for nested types and namespaces in C++ has been
3131 improved, especially if you use the DWARF 2 debugging format. (This
3132 is the default for recent versions of GCC on most platforms.)
3133 Specifically, if you have a class "Inner" defined within a class or
3134 namespace "Outer", then GDB realizes that the class's name is
3135 "Outer::Inner", not simply "Inner". This should greatly reduce the
3136 frequency of complaints about not finding RTTI symbols. In addition,
3137 if you are stopped at inside of a function defined within a namespace,
3138 GDB modifies its name lookup accordingly.
3140 * New native configurations
3142 NetBSD/amd64 x86_64-*-netbsd*
3143 OpenBSD/amd64 x86_64-*-openbsd*
3144 OpenBSD/alpha alpha*-*-openbsd*
3145 OpenBSD/sparc sparc-*-openbsd*
3146 OpenBSD/sparc64 sparc64-*-openbsd*
3148 * New debugging protocols
3150 M32R with SDI protocol m32r-*-elf*
3152 * "set prompt-escape-char" command deleted.
3154 The command "set prompt-escape-char" has been deleted. This command,
3155 and its very obscure effet on GDB's prompt, was never documented,
3156 tested, nor mentioned in the NEWS file.
3158 * OBSOLETE configurations and files
3160 Configurations that have been declared obsolete in this release have
3161 been commented out. Unless there is activity to revive these
3162 configurations, the next release of GDB will have their sources
3163 permanently REMOVED.
3165 Sun 3, running SunOS 3 m68*-*-sunos3*
3166 Sun 3, running SunOS 4 m68*-*-sunos4*
3167 Sun 2, running SunOS 3 m68000-*-sunos3*
3168 Sun 2, running SunOS 4 m68000-*-sunos4*
3169 Motorola 680x0 running LynxOS m68*-*-lynxos*
3170 AT&T 3b1/Unix pc m68*-att-*
3171 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3172 decstation mips-dec-* mips-little-*
3173 riscos mips-*-riscos* mips-*-sysv*
3174 sonymips mips-sony-*
3175 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3177 * REMOVED configurations and files
3179 SGI Irix-4.x mips-sgi-irix4 or iris4
3180 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3181 Z8000 simulator z8k-zilog-none or z8ksim
3182 Matsushita MN10200 w/simulator mn10200-*-*
3183 H8/500 simulator h8500-hitachi-hms or h8500hms
3184 HP/PA running BSD hppa*-*-bsd*
3185 HP/PA running OSF/1 hppa*-*-osf*
3186 HP/PA Pro target hppa*-*-pro*
3187 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3188 386BSD i[3456]86-*-bsd*
3189 Sequent family i[3456]86-sequent-sysv4*
3190 i[3456]86-sequent-sysv*
3191 i[3456]86-sequent-bsd*
3192 SPARC running LynxOS sparc-*-lynxos*
3193 SPARC running SunOS 4 sparc-*-sunos4*
3194 Tsqware Sparclet sparclet-*-*
3195 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3197 *** Changes in GDB 6.0:
3201 Support for debugging the Objective-C programming language has been
3202 integrated into GDB.
3204 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3206 DWARF 2's Call Frame Information makes available compiler generated
3207 information that more exactly describes the program's run-time stack.
3208 By using this information, GDB is able to provide more robust stack
3211 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3212 have been updated to use a new backtrace mechanism which includes
3213 DWARF 2 CFI support.
3217 GDB's remote protocol has been extended to include support for hosted
3218 file I/O (where the remote target uses GDB's file system). See GDB's
3219 remote protocol documentation for details.
3221 * All targets using the new architecture framework.
3223 All of GDB's targets have been updated to use the new internal
3224 architecture framework. The way is now open for future GDB releases
3225 to include cross-architecture native debugging support (i386 on amd64,
3228 * GNU/Linux's Thread Local Storage (TLS)
3230 GDB now includes support for for the GNU/Linux implementation of
3231 per-thread variables.
3233 * GNU/Linux's Native POSIX Thread Library (NPTL)
3235 GDB's thread code has been updated to work with either the new
3236 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3238 * Separate debug info.
3240 GDB, in conjunction with BINUTILS, now supports a mechanism for
3241 automatically loading debug information from a separate file. Instead
3242 of shipping full debug and non-debug versions of system libraries,
3243 system integrators can now instead ship just the stripped libraries
3244 and optional debug files.
3246 * DWARF 2 Location Expressions
3248 DWARF 2 Location Expressions allow the compiler to more completely
3249 describe the location of variables (even in optimized code) to the
3252 GDB now includes preliminary support for location expressions (support
3253 for DW_OP_piece is still missing).
3257 A number of long standing bugs that caused GDB to die while starting a
3258 Java application have been fixed. GDB's Java support is now
3259 considered "useable".
3261 * GNU/Linux support for fork, vfork, and exec.
3263 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3264 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3267 * GDB supports logging output to a file
3269 There are two new commands, "set logging" and "show logging", which can be
3270 used to capture GDB's output to a file.
3272 * The meaning of "detach" has changed for gdbserver
3274 The "detach" command will now resume the application, as documented. To
3275 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3278 * d10v, m68hc11 `regs' command deprecated
3280 The `info registers' command has been updated so that it displays the
3281 registers using a format identical to the old `regs' command.
3285 A new command, "maint set profile on/off", has been added. This command can
3286 be used to enable or disable profiling while running GDB, to profile a
3287 session or a set of commands. In addition there is a new configure switch,
3288 "--enable-profiling", which will cause GDB to be compiled with profiling
3289 data, for more informative profiling results.
3291 * Default MI syntax changed to "mi2".
3293 The default MI (machine interface) syntax, enabled by the command line
3294 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3295 "mi1", can be enabled by specifying the option "-i=mi1".
3297 Support for the original "mi0" syntax (included in GDB 5.0) has been
3300 Fix for gdb/192: removed extraneous space when displaying frame level.
3301 Fix for gdb/672: update changelist is now output in mi list format.
3302 Fix for gdb/702: a -var-assign that updates the value now shows up
3303 in a subsequent -var-update.
3305 * New native configurations.
3307 FreeBSD/amd64 x86_64-*-freebsd*
3309 * Multi-arched targets.
3311 HP/PA HPUX11 hppa*-*-hpux*
3312 Renesas M32R/D w/simulator m32r-*-elf*
3314 * OBSOLETE configurations and files
3316 Configurations that have been declared obsolete in this release have
3317 been commented out. Unless there is activity to revive these
3318 configurations, the next release of GDB will have their sources
3319 permanently REMOVED.
3321 Z8000 simulator z8k-zilog-none or z8ksim
3322 Matsushita MN10200 w/simulator mn10200-*-*
3323 H8/500 simulator h8500-hitachi-hms or h8500hms
3324 HP/PA running BSD hppa*-*-bsd*
3325 HP/PA running OSF/1 hppa*-*-osf*
3326 HP/PA Pro target hppa*-*-pro*
3327 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3328 Sequent family i[3456]86-sequent-sysv4*
3329 i[3456]86-sequent-sysv*
3330 i[3456]86-sequent-bsd*
3331 Tsqware Sparclet sparclet-*-*
3332 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3334 * REMOVED configurations and files
3337 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3338 IBM AIX PS/2 i[3456]86-*-aix
3339 i386 running Mach 3.0 i[3456]86-*-mach3*
3340 i386 running Mach i[3456]86-*-mach*
3341 i386 running OSF/1 i[3456]86-*osf1mk*
3342 HP/Apollo 68k Family m68*-apollo*-sysv*,
3344 m68*-hp-bsd*, m68*-hp-hpux*
3345 Argonaut Risc Chip (ARC) arc-*-*
3346 Mitsubishi D30V d30v-*-*
3347 Fujitsu FR30 fr30-*-elf*
3348 OS/9000 i[34]86-*-os9k
3349 I960 with MON960 i960-*-coff
3351 * MIPS $fp behavior changed
3353 The convenience variable $fp, for the MIPS, now consistently returns
3354 the address of the current frame's base. Previously, depending on the
3355 context, $fp could refer to either $sp or the current frame's base
3356 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3357 The GNU Source-Level Debugger''.
3359 *** Changes in GDB 5.3:
3361 * GNU/Linux shared library multi-threaded performance improved.
3363 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3364 `/proc', in preference to `ptrace' for memory reads. This may result
3365 in an improvement in the start-up time of multi-threaded, shared
3366 library applications when run under GDB. One GDB user writes: ``loads
3367 shared libs like mad''.
3369 * ``gdbserver'' now supports multi-threaded applications on some targets
3371 Support for debugging multi-threaded applications which use
3372 the GNU/Linux LinuxThreads package has been added for
3373 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3374 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3376 * GDB now supports C/C++ preprocessor macros.
3378 GDB now expands preprocessor macro invocations in C/C++ expressions,
3379 and provides various commands for showing macro definitions and how
3382 The new command `macro expand EXPRESSION' expands any macro
3383 invocations in expression, and shows the result.
3385 The new command `show macro MACRO-NAME' shows the definition of the
3386 macro named MACRO-NAME, and where it was defined.
3388 Most compilers don't include information about macros in the debugging
3389 information by default. In GCC 3.1, for example, you need to compile
3390 your program with the options `-gdwarf-2 -g3'. If the macro
3391 information is present in the executable, GDB will read it.
3393 * Multi-arched targets.
3395 DEC Alpha (partial) alpha*-*-*
3396 DEC VAX (partial) vax-*-*
3398 National Semiconductor NS32000 (partial) ns32k-*-*
3399 Motorola 68000 (partial) m68k-*-*
3400 Motorola MCORE mcore-*-*
3404 Fujitsu FRV architecture added by Red Hat frv*-*-*
3407 * New native configurations
3409 Alpha NetBSD alpha*-*-netbsd*
3410 SH NetBSD sh*-*-netbsdelf*
3411 MIPS NetBSD mips*-*-netbsd*
3412 UltraSPARC NetBSD sparc64-*-netbsd*
3414 * OBSOLETE configurations and files
3416 Configurations that have been declared obsolete in this release have
3417 been commented out. Unless there is activity to revive these
3418 configurations, the next release of GDB will have their sources
3419 permanently REMOVED.
3421 Mitsubishi D30V d30v-*-*
3422 OS/9000 i[34]86-*-os9k
3423 IBM AIX PS/2 i[3456]86-*-aix
3424 Fujitsu FR30 fr30-*-elf*
3425 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3426 Argonaut Risc Chip (ARC) arc-*-*
3427 i386 running Mach 3.0 i[3456]86-*-mach3*
3428 i386 running Mach i[3456]86-*-mach*
3429 i386 running OSF/1 i[3456]86-*osf1mk*
3430 HP/Apollo 68k Family m68*-apollo*-sysv*,
3432 m68*-hp-bsd*, m68*-hp-hpux*
3433 I960 with MON960 i960-*-coff
3435 * OBSOLETE languages
3437 CHILL, a Pascal like language used by telecommunications companies.
3439 * REMOVED configurations and files
3441 AMD 29k family via UDI a29k-amd-udi, udi29k
3442 A29K VxWorks a29k-*-vxworks
3443 AMD 29000 embedded, using EBMON a29k-none-none
3444 AMD 29000 embedded with COFF a29k-none-coff
3445 AMD 29000 embedded with a.out a29k-none-aout
3447 testsuite/gdb.hp/gdb.threads-hp/ directory
3449 * New command "set max-user-call-depth <nnn>"
3451 This command allows the user to limit the call depth of user-defined
3452 commands. The default is 1024.
3454 * Changes in FreeBSD/i386 native debugging.
3456 Support for the "generate-core-file" has been added.
3458 * New commands "dump", "append", and "restore".
3460 These commands allow data to be copied from target memory
3461 to a bfd-format or binary file (dump and append), and back
3462 from a file into memory (restore).
3464 * Improved "next/step" support on multi-processor Alpha Tru64.
3466 The previous single-step mechanism could cause unpredictable problems,
3467 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3468 of a software single-step mechanism prevents this.
3470 *** Changes in GDB 5.2.1:
3478 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3479 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3480 Fix, by Joel Brobecker imported from mainline.
3482 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3483 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3484 Fix, by Fred Fish, imported from mainline.
3486 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3487 Surprisingly enough, it works now.
3488 By Michal Ludvig, imported from mainline.
3490 i386 hardware watchpoint support:
3491 avoid misses on second run for some targets.
3492 By Pierre Muller, imported from mainline.
3494 *** Changes in GDB 5.2:
3496 * New command "set trust-readonly-sections on[off]".
3498 This command is a hint that tells gdb that read-only sections
3499 really are read-only (ie. that their contents will not change).
3500 In this mode, gdb will go to the object file rather than the
3501 target to read memory from read-only sections (such as ".text").
3502 This can be a significant performance improvement on some
3503 (notably embedded) targets.
3505 * New command "generate-core-file" (or "gcore").
3507 This new gdb command allows the user to drop a core file of the child
3508 process state at any time. So far it's been implemented only for
3509 GNU/Linux and Solaris, but should be relatively easily ported to other
3510 hosts. Argument is core file name (defaults to core.<pid>).
3512 * New command line option
3514 GDB now accepts --pid or -p followed by a process id.
3516 * Change in command line behavior -- corefiles vs. process ids.
3518 There is a subtle behavior in the way in which GDB handles
3519 command line arguments. The first non-flag argument is always
3520 a program to debug, but the second non-flag argument may either
3521 be a corefile or a process id. Previously, GDB would attempt to
3522 open the second argument as a corefile, and if that failed, would
3523 issue a superfluous error message and then attempt to attach it as
3524 a process. Now, if the second argument begins with a non-digit,
3525 it will be treated as a corefile. If it begins with a digit,
3526 GDB will attempt to attach it as a process, and if no such process
3527 is found, will then attempt to open it as a corefile.
3529 * Changes in ARM configurations.
3531 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3532 configuration is fully multi-arch.
3534 * New native configurations
3536 ARM NetBSD arm*-*-netbsd*
3537 x86 OpenBSD i[3456]86-*-openbsd*
3538 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3539 Sparc64 running FreeBSD sparc64-*-freebsd*
3543 Sanyo XStormy16 xstormy16-elf
3545 * OBSOLETE configurations and files
3547 Configurations that have been declared obsolete in this release have
3548 been commented out. Unless there is activity to revive these
3549 configurations, the next release of GDB will have their sources
3550 permanently REMOVED.
3552 AMD 29k family via UDI a29k-amd-udi, udi29k
3553 A29K VxWorks a29k-*-vxworks
3554 AMD 29000 embedded, using EBMON a29k-none-none
3555 AMD 29000 embedded with COFF a29k-none-coff
3556 AMD 29000 embedded with a.out a29k-none-aout
3558 testsuite/gdb.hp/gdb.threads-hp/ directory
3560 * REMOVED configurations and files
3562 TI TMS320C80 tic80-*-*
3564 PowerPC Solaris powerpcle-*-solaris*
3565 PowerPC Windows NT powerpcle-*-cygwin32
3566 PowerPC Netware powerpc-*-netware*
3567 Harris/CXUX m88k m88*-harris-cxux*
3568 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3569 ns32k-utek-sysv* ns32k-utek-*
3570 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3571 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3572 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3573 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3574 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3576 * Changes to command line processing
3578 The new `--args' feature can be used to specify command-line arguments
3579 for the inferior from gdb's command line.
3581 * Changes to key bindings
3583 There is a new `operate-and-get-next' function bound to `C-o'.
3585 *** Changes in GDB 5.1.1
3587 Fix compile problem on DJGPP.
3589 Fix a problem with floating-point registers on the i386 being
3592 Fix to stop GDB crashing on .debug_str debug info.
3594 Numerous documentation fixes.
3596 Numerous testsuite fixes.
3598 *** Changes in GDB 5.1:
3600 * New native configurations
3602 Alpha FreeBSD alpha*-*-freebsd*
3603 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3604 MIPS GNU/Linux mips*-*-linux*
3605 MIPS SGI Irix 6.x mips*-sgi-irix6*
3606 ia64 AIX ia64-*-aix*
3607 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3611 Motorola 68HC11 and 68HC12 m68hc11-elf
3613 UltraSparc running GNU/Linux sparc64-*-linux*
3615 * OBSOLETE configurations and files
3617 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3618 Harris/CXUX m88k m88*-harris-cxux*
3619 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3620 ns32k-utek-sysv* ns32k-utek-*
3621 TI TMS320C80 tic80-*-*
3623 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3624 PowerPC Solaris powerpcle-*-solaris*
3625 PowerPC Windows NT powerpcle-*-cygwin32
3626 PowerPC Netware powerpc-*-netware*
3627 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3628 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3629 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3630 Apple Macintosh (MPW) host N/A
3632 stuff.c (Program to stuff files into a specially prepared space in kdb)
3633 kdb-start.c (Main loop for the standalone kernel debugger)
3635 Configurations that have been declared obsolete in this release have
3636 been commented out. Unless there is activity to revive these
3637 configurations, the next release of GDB will have their sources
3638 permanently REMOVED.
3640 * REMOVED configurations and files
3642 Altos 3068 m68*-altos-*
3643 Convex c1-*-*, c2-*-*
3645 ARM RISCix arm-*-* (as host)
3649 * GDB has been converted to ISO C.
3651 GDB's source code has been converted to ISO C. In particular, the
3652 sources are fully protoized, and rely on standard headers being
3657 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3659 * The MI enabled by default.
3661 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3662 revised and enabled by default. Packages which use GDB as a debugging
3663 engine behind a UI or another front end are encouraged to switch to
3664 using the GDB/MI interface, instead of the old annotations interface
3665 which is now deprecated.
3667 * Support for debugging Pascal programs.
3669 GDB now includes support for debugging Pascal programs. The following
3670 main features are supported:
3672 - Pascal-specific data types such as sets;
3674 - automatic recognition of Pascal sources based on file-name
3677 - Pascal-style display of data types, variables, and functions;
3679 - a Pascal expression parser.
3681 However, some important features are not yet supported.
3683 - Pascal string operations are not supported at all;
3685 - there are some problems with boolean types;
3687 - Pascal type hexadecimal constants are not supported
3688 because they conflict with the internal variables format;
3690 - support for Pascal objects and classes is not full yet;
3692 - unlike Pascal, GDB is case-sensitive for symbol names.
3694 * Changes in completion.
3696 Commands such as `shell', `run' and `set args', which pass arguments
3697 to inferior programs, now complete on file names, similar to what
3698 users expect at the shell prompt.
3700 Commands which accept locations, such as `disassemble', `print',
3701 `breakpoint', `until', etc. now complete on filenames as well as
3702 program symbols. Thus, if you type "break foob TAB", and the source
3703 files linked into the programs include `foobar.c', that file name will
3704 be one of the candidates for completion. However, file names are not
3705 considered for completion after you typed a colon that delimits a file
3706 name from a name of a function in that file, as in "break foo.c:bar".
3708 `set demangle-style' completes on available demangling styles.
3710 * New platform-independent commands:
3712 It is now possible to define a post-hook for a command as well as a
3713 hook that runs before the command. For more details, see the
3714 documentation of `hookpost' in the GDB manual.
3716 * Changes in GNU/Linux native debugging.
3718 Support for debugging multi-threaded programs has been completely
3719 revised for all platforms except m68k and sparc. You can now debug as
3720 many threads as your system allows you to have.
3722 Attach/detach is supported for multi-threaded programs.
3724 Support for SSE registers was added for x86. This doesn't work for
3725 multi-threaded programs though.
3727 * Changes in MIPS configurations.
3729 Multi-arch support is enabled for all MIPS configurations.
3731 GDB can now be built as native debugger on SGI Irix 6.x systems for
3732 debugging n32 executables. (Debugging 64-bit executables is not yet
3735 * Unified support for hardware watchpoints in all x86 configurations.
3737 Most (if not all) native x86 configurations support hardware-assisted
3738 breakpoints and watchpoints in a unified manner. This support
3739 implements debug register sharing between watchpoints, which allows to
3740 put a virtually infinite number of watchpoints on the same address,
3741 and also supports watching regions up to 16 bytes with several debug
3744 The new maintenance command `maintenance show-debug-regs' toggles
3745 debugging print-outs in functions that insert, remove, and test
3746 watchpoints and hardware breakpoints.
3748 * Changes in the DJGPP native configuration.
3750 New command ``info dos sysinfo'' displays assorted information about
3751 the CPU, OS, memory, and DPMI server.
3753 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3754 display information about segment descriptors stored in GDT, LDT, and
3757 New commands ``info dos pde'' and ``info dos pte'' display entries
3758 from Page Directory and Page Tables (for now works with CWSDPMI only).
3759 New command ``info dos address-pte'' displays the Page Table entry for
3760 a given linear address.
3762 GDB can now pass command lines longer than 126 characters to the
3763 program being debugged (requires an update to the libdbg.a library
3764 which is part of the DJGPP development kit).
3766 DWARF2 debug info is now supported.
3768 It is now possible to `step' and `next' through calls to `longjmp'.
3770 * Changes in documentation.
3772 All GDB documentation was converted to GFDL, the GNU Free
3773 Documentation License.
3775 Tracepoints-related commands are now fully documented in the GDB
3778 TUI, the Text-mode User Interface, is now documented in the manual.
3780 Tracepoints-related commands are now fully documented in the GDB
3783 The "GDB Internals" manual now has an index. It also includes
3784 documentation of `ui_out' functions, GDB coding standards, x86
3785 hardware watchpoints, and memory region attributes.
3787 * GDB's version number moved to ``version.in''
3789 The Makefile variable VERSION has been replaced by the file
3790 ``version.in''. People creating GDB distributions should update the
3791 contents of this file.
3795 GUD support is now a standard part of the EMACS distribution.
3797 *** Changes in GDB 5.0:
3799 * Improved support for debugging FP programs on x86 targets
3801 Unified and much-improved support for debugging floating-point
3802 programs on all x86 targets. In particular, ``info float'' now
3803 displays the FP registers in the same format on all x86 targets, with
3804 greater level of detail.
3806 * Improvements and bugfixes in hardware-assisted watchpoints
3808 It is now possible to watch array elements, struct members, and
3809 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3810 on x86 targets no longer erroneously trigger when the address is
3813 * Improvements in the native DJGPP version of GDB
3815 The distribution now includes all the scripts and auxiliary files
3816 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3817 machines ``out of the box''.
3819 The DJGPP version can now debug programs that use signals. It is
3820 possible to catch signals that happened in the debuggee, deliver
3821 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3822 would kill the program being debugged.) Programs that hook hardware
3823 interrupts (keyboard, timer, etc.) can also be debugged.
3825 It is now possible to debug DJGPP programs that redirect their
3826 standard handles or switch them to raw (as opposed to cooked) mode, or
3827 even close them. The command ``run < foo > bar'' works as expected,
3828 and ``info terminal'' reports useful information about the debuggee's
3829 terminal, including raw/cooked mode, redirection, etc.
3831 The DJGPP version now uses termios functions for console I/O, which
3832 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3835 DOS-style file names with drive letters are now fully supported by
3838 It is now possible to debug DJGPP programs that switch their working
3839 directory. It is also possible to rerun the debuggee any number of
3840 times without restarting GDB; thus, you can use the same setup,
3841 breakpoints, etc. for many debugging sessions.
3843 * New native configurations
3845 ARM GNU/Linux arm*-*-linux*
3846 PowerPC GNU/Linux powerpc-*-linux*
3850 Motorola MCore mcore-*-*
3851 x86 VxWorks i[3456]86-*-vxworks*
3852 PowerPC VxWorks powerpc-*-vxworks*
3853 TI TMS320C80 tic80-*-*
3855 * OBSOLETE configurations
3857 Altos 3068 m68*-altos-*
3858 Convex c1-*-*, c2-*-*
3860 ARM RISCix arm-*-* (as host)
3863 Configurations that have been declared obsolete will be commented out,
3864 but the code will be left in place. If there is no activity to revive
3865 these configurations before the next release of GDB, the sources will
3866 be permanently REMOVED.
3868 * Gould support removed
3870 Support for the Gould PowerNode and NP1 has been removed.
3872 * New features for SVR4
3874 On SVR4 native platforms (such as Solaris), if you attach to a process
3875 without first loading a symbol file, GDB will now attempt to locate and
3876 load symbols from the running process's executable file.
3878 * Many C++ enhancements
3880 C++ support has been greatly improved. Overload resolution now works properly
3881 in almost all cases. RTTI support is on the way.
3883 * Remote targets can connect to a sub-program
3885 A popen(3) style serial-device has been added. This device starts a
3886 sub-process (such as a stand-alone simulator) and then communicates
3887 with that. The sub-program to run is specified using the syntax
3888 ``|<program> <args>'' vis:
3890 (gdb) set remotedebug 1
3891 (gdb) target extended-remote |mn10300-elf-sim program-args
3893 * MIPS 64 remote protocol
3895 A long standing bug in the mips64 remote protocol where by GDB
3896 expected certain 32 bit registers (ex SR) to be transfered as 32
3897 instead of 64 bits has been fixed.
3899 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3900 added to provide backward compatibility with older versions of GDB.
3902 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3904 The command ``set remotebinarydownload'' command has been replaced by
3905 ``set remote X-packet''. Other commands in ``set remote'' family
3906 include ``set remote P-packet''.
3908 * Breakpoint commands accept ranges.
3910 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3911 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3912 ``tracepoint passcount'' also accepts a range of tracepoints.
3914 * ``apropos'' command added.
3916 The ``apropos'' command searches through command names and
3917 documentation strings, printing out matches, making it much easier to
3918 try to find a command that does what you are looking for.
3922 A new machine oriented interface (MI) has been added to GDB. This
3923 interface is designed for debug environments running GDB as a separate
3924 process. This is part of the long term libGDB project. See the
3925 "GDB/MI" chapter of the GDB manual for further information. It can be
3926 enabled by configuring with:
3928 .../configure --enable-gdbmi
3930 *** Changes in GDB-4.18:
3932 * New native configurations
3934 HP-UX 10.20 hppa*-*-hpux10.20
3935 HP-UX 11.x hppa*-*-hpux11.0*
3936 M68K GNU/Linux m68*-*-linux*
3940 Fujitsu FR30 fr30-*-elf*
3941 Intel StrongARM strongarm-*-*
3942 Mitsubishi D30V d30v-*-*
3944 * OBSOLETE configurations
3946 Gould PowerNode, NP1 np1-*-*, pn-*-*
3948 Configurations that have been declared obsolete will be commented out,
3949 but the code will be left in place. If there is no activity to revive
3950 these configurations before the next release of GDB, the sources will
3951 be permanently REMOVED.
3955 As a compatibility experiment, GDB's source files buildsym.h and
3956 buildsym.c have been converted to pure standard C, no longer
3957 containing any K&R compatibility code. We believe that all systems in
3958 use today either come with a standard C compiler, or have a GCC port
3959 available. If this is not true, please report the affected
3960 configuration to bug-gdb@gnu.org immediately. See the README file for
3961 information about getting a standard C compiler if you don't have one
3966 GDB now uses readline 2.2.
3968 * set extension-language
3970 You can now control the mapping between filename extensions and source
3971 languages by using the `set extension-language' command. For instance,
3972 you can ask GDB to treat .c files as C++ by saying
3973 set extension-language .c c++
3974 The command `info extensions' lists all of the recognized extensions
3975 and their associated languages.
3977 * Setting processor type for PowerPC and RS/6000
3979 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3980 you can use the `set processor' command to specify what variant of the
3981 PowerPC family you are debugging. The command
3985 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3986 following PowerPC and RS6000 variants:
3988 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3989 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3991 403GC IBM PowerPC 403GC
3992 505 Motorola PowerPC 505
3993 860 Motorola PowerPC 860 or 850
3994 601 Motorola PowerPC 601
3995 602 Motorola PowerPC 602
3996 603 Motorola/IBM PowerPC 603 or 603e
3997 604 Motorola PowerPC 604 or 604e
3998 750 Motorola/IBM PowerPC 750 or 750
4000 At the moment, this command just tells GDB what to name the
4001 special-purpose processor registers. Since almost all the affected
4002 registers are inaccessible to user-level programs, this command is
4003 only useful for remote debugging in its present form.
4007 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4008 more extensive support for HP-UX. Added features include shared
4009 library support, kernel threads and hardware watchpoints for 11.00,
4010 support for HP's ANSI C and C++ compilers, and a compatibility mode
4011 for xdb and dbx commands.
4015 HP's donation includes the new concept of catchpoints, which is a
4016 generalization of the old catch command. On HP-UX, it is now possible
4017 to catch exec, fork, and vfork, as well as library loading.
4019 This means that the existing catch command has changed; its first
4020 argument now specifies the type of catch to be set up. See the
4021 output of "help catch" for a list of catchpoint types.
4023 * Debugging across forks
4025 On HP-UX, you can choose which process to debug when a fork() happens
4030 HP has donated a curses-based terminal user interface (TUI). To get
4031 it, build with --enable-tui. Although this can be enabled for any
4032 configuration, at present it only works for native HP debugging.
4034 * GDB remote protocol additions
4036 A new protocol packet 'X' that writes binary data is now available.
4037 Default behavior is to try 'X', then drop back to 'M' if the stub
4038 fails to respond. The settable variable `remotebinarydownload'
4039 allows explicit control over the use of 'X'.
4041 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4042 full 64-bit address. The command
4044 set remoteaddresssize 32
4046 can be used to revert to the old behaviour. For existing remote stubs
4047 the change should not be noticed, as the additional address information
4050 In order to assist in debugging stubs, you may use the maintenance
4051 command `packet' to send any text string to the stub. For instance,
4053 maint packet heythere
4055 sends the packet "$heythere#<checksum>". Note that it is very easy to
4056 disrupt a debugging session by sending the wrong packet at the wrong
4059 The compare-sections command allows you to compare section data on the
4060 target to what is in the executable file without uploading or
4061 downloading, by comparing CRC checksums.
4063 * Tracing can collect general expressions
4065 You may now collect general expressions at tracepoints. This requires
4066 further additions to the target-side stub; see tracepoint.c and
4067 doc/agentexpr.texi for further details.
4069 * mask-address variable for Mips
4071 For Mips targets, you may control the zeroing of the upper 32 bits of
4072 a 64-bit address by entering `set mask-address on'. This is mainly
4073 of interest to users of embedded R4xxx and R5xxx processors.
4075 * Higher serial baud rates
4077 GDB's serial code now allows you to specify baud rates 57600, 115200,
4078 230400, and 460800 baud. (Note that your host system may not be able
4079 to achieve all of these rates.)
4083 The i960 configuration now includes an initial implementation of a
4084 builtin simulator, contributed by Jim Wilson.
4087 *** Changes in GDB-4.17:
4089 * New native configurations
4091 Alpha GNU/Linux alpha*-*-linux*
4092 Unixware 2.x i[3456]86-unixware2*
4093 Irix 6.x mips*-sgi-irix6*
4094 PowerPC GNU/Linux powerpc-*-linux*
4095 PowerPC Solaris powerpcle-*-solaris*
4096 Sparc GNU/Linux sparc-*-linux*
4097 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4101 Argonaut Risc Chip (ARC) arc-*-*
4102 Hitachi H8/300S h8300*-*-*
4103 Matsushita MN10200 w/simulator mn10200-*-*
4104 Matsushita MN10300 w/simulator mn10300-*-*
4105 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4106 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4107 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4108 Mitsubishi D10V w/simulator d10v-*-*
4109 Mitsubishi M32R/D w/simulator m32r-*-elf*
4110 Tsqware Sparclet sparclet-*-*
4111 NEC V850 w/simulator v850-*-*
4113 * New debugging protocols
4115 ARM with RDI protocol arm*-*-*
4116 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4117 DDB and LSI variants of PMON protocol mips*-*-*
4118 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4119 PowerPC with SDS protocol powerpc{,le}-*-eabi
4120 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4124 All configurations can now understand and use the DWARF 2 debugging
4125 format. The choice is automatic, if the symbol file contains DWARF 2
4130 GDB now includes basic Java language support. This support is
4131 only useful with Java compilers that produce native machine code.
4133 * solib-absolute-prefix and solib-search-path
4135 For SunOS and SVR4 shared libraries, you may now set the prefix for
4136 loading absolute shared library symbol files, and the search path for
4137 locating non-absolute shared library symbol files.
4139 * Live range splitting
4141 GDB can now effectively debug code for which GCC has performed live
4142 range splitting as part of its optimization. See gdb/doc/LRS for
4143 more details on the expected format of the stabs information.
4147 GDB's support for the GNU Hurd, including thread debugging, has been
4148 updated to work with current versions of the Hurd.
4152 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4153 instruction set. ARM GDB automatically detects when Thumb
4154 instructions are in use, and adjusts disassembly and backtracing
4159 GDB's MIPS target configurations now handle the MIP16 16-bit
4164 GDB now includes support for overlays; if an executable has been
4165 linked such that multiple sections are based at the same address, GDB
4166 will decide which section to use for symbolic info. You can choose to
4167 control the decision manually, using overlay commands, or implement
4168 additional target-side support and use "overlay load-target" to bring
4169 in the overlay mapping. Do "help overlay" for more detail.
4173 The command "info symbol <address>" displays information about
4174 the symbol at the specified address.
4178 The standard remote protocol now includes an extension that allows
4179 asynchronous collection and display of trace data. This requires
4180 extensive support in the target-side debugging stub. Tracing mode
4181 includes a new interaction mode in GDB and new commands: see the
4182 file tracepoint.c for more details.
4186 Configurations for embedded MIPS now include a simulator contributed
4187 by Cygnus Solutions. The simulator supports the instruction sets
4188 of most MIPS variants.
4192 Sparc configurations may now include the ERC32 simulator contributed
4193 by the European Space Agency. The simulator is not built into
4194 Sparc targets by default; configure with --enable-sim to include it.
4198 For target configurations that may include multiple variants of a
4199 basic architecture (such as MIPS and SH), you may now set the
4200 architecture explicitly. "set arch" sets, "info arch" lists
4201 the possible architectures.
4203 *** Changes in GDB-4.16:
4205 * New native configurations
4207 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4208 M68K NetBSD m68k-*-netbsd*
4209 PowerPC AIX 4.x powerpc-*-aix*
4210 PowerPC MacOS powerpc-*-macos*
4211 PowerPC Windows NT powerpcle-*-cygwin32
4212 RS/6000 AIX 4.x rs6000-*-aix4*
4216 ARM with RDP protocol arm-*-*
4217 I960 with MON960 i960-*-coff
4218 MIPS VxWorks mips*-*-vxworks*
4219 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4220 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4222 Matra Sparclet sparclet-*-*
4226 The powerpc-eabi configuration now includes the PSIM simulator,
4227 contributed by Andrew Cagney, with assistance from Mike Meissner.
4228 PSIM is a very elaborate model of the PowerPC, including not only
4229 basic instruction set execution, but also details of execution unit
4230 performance and I/O hardware. See sim/ppc/README for more details.
4234 GDB now works with Solaris 2.5.
4236 * Windows 95/NT native
4238 GDB will now work as a native debugger on Windows 95 and Windows NT.
4239 To build it from source, you must use the "gnu-win32" environment,
4240 which uses a DLL to emulate enough of Unix to run the GNU tools.
4241 Further information, binaries, and sources are available at
4242 ftp.cygnus.com, under pub/gnu-win32.
4244 * dont-repeat command
4246 If a user-defined command includes the command `dont-repeat', then the
4247 command will not be repeated if the user just types return. This is
4248 useful if the command is time-consuming to run, so that accidental
4249 extra keystrokes don't run the same command many times.
4251 * Send break instead of ^C
4253 The standard remote protocol now includes an option to send a break
4254 rather than a ^C to the target in order to interrupt it. By default,
4255 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4257 * Remote protocol timeout
4259 The standard remote protocol includes a new variable `remotetimeout'
4260 that allows you to set the number of seconds before GDB gives up trying
4261 to read from the target. The default value is 2.
4263 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4265 By default GDB will automatically keep track of objects as they are
4266 loaded and unloaded by the dynamic linker. By using the command `set
4267 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4268 when shared library events occur, thus allowing you to set breakpoints
4269 in shared libraries which are explicitly loaded by the inferior.
4271 Note this feature does not work on hpux8. On hpux9 you must link
4272 /usr/lib/end.o into your program. This feature should work
4273 automatically on hpux10.
4275 * Irix 5.x hardware watchpoint support
4277 Irix 5 configurations now support the use of hardware watchpoints.
4279 * Mips protocol "SYN garbage limit"
4281 When debugging a Mips target using the `target mips' protocol, you
4282 may set the number of characters that GDB will ignore by setting
4283 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4284 every character. The default value is 1050.
4286 * Recording and replaying remote debug sessions
4288 If you set `remotelogfile' to the name of a file, gdb will write to it
4289 a recording of a remote debug session. This recording may then be
4290 replayed back to gdb using "gdbreplay". See gdbserver/README for
4291 details. This is useful when you have a problem with GDB while doing
4292 remote debugging; you can make a recording of the session and send it
4293 to someone else, who can then recreate the problem.
4295 * Speedups for remote debugging
4297 GDB includes speedups for downloading and stepping MIPS systems using
4298 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4299 and more efficient S-record downloading.
4301 * Memory use reductions and statistics collection
4303 GDB now uses less memory and reports statistics about memory usage.
4304 Try the `maint print statistics' command, for example.
4306 *** Changes in GDB-4.15:
4308 * Psymtabs for XCOFF
4310 The symbol reader for AIX GDB now uses partial symbol tables. This
4311 can greatly improve startup time, especially for large executables.
4313 * Remote targets use caching
4315 Remote targets now use a data cache to speed up communication with the
4316 remote side. The data cache could lead to incorrect results because
4317 it doesn't know about volatile variables, thus making it impossible to
4318 debug targets which use memory mapped I/O devices. `set remotecache
4319 off' turns the the data cache off.
4321 * Remote targets may have threads
4323 The standard remote protocol now includes support for multiple threads
4324 in the target system, using new protocol commands 'H' and 'T'. See
4325 gdb/remote.c for details.
4329 If GDB is configured with `--enable-netrom', then it will include
4330 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4331 acts as though it is a bank of ROM on the target board, but you can
4332 write into it over the network. GDB's support consists only of
4333 support for fast loading into the emulated ROM; to debug, you must use
4334 another protocol, such as standard remote protocol. The usual
4335 sequence is something like
4337 target nrom <netrom-hostname>
4339 target remote <netrom-hostname>:1235
4343 GDB now includes support for the Apple Macintosh, as a host only. It
4344 may be run as either an MPW tool or as a standalone application, and
4345 it can debug through the serial port. All the usual GDB commands are
4346 available, but to the target command, you must supply "serial" as the
4347 device type instead of "/dev/ttyXX". See mpw-README in the main
4348 directory for more information on how to build. The MPW configuration
4349 scripts */mpw-config.in support only a few targets, and only the
4350 mips-idt-ecoff target has been tested.
4354 GDB configuration now uses autoconf. This is not user-visible,
4355 but does simplify configuration and building.
4359 GDB now supports hpux10.
4361 *** Changes in GDB-4.14:
4363 * New native configurations
4365 x86 FreeBSD i[345]86-*-freebsd
4366 x86 NetBSD i[345]86-*-netbsd
4367 NS32k NetBSD ns32k-*-netbsd
4368 Sparc NetBSD sparc-*-netbsd
4372 A29K VxWorks a29k-*-vxworks
4373 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4374 CPU32 EST-300 emulator m68*-*-est*
4375 PowerPC ELF powerpc-*-elf
4378 * Alpha OSF/1 support for procfs
4380 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4381 possible to attach to running processes. As the mounting of the /proc
4382 filesystem is optional on the Alpha, GDB automatically determines
4383 the availability of /proc during startup. This can lead to problems
4384 if /proc is unmounted after GDB has been started.
4386 * Arguments to user-defined commands
4388 User commands may accept up to 10 arguments separated by whitespace.
4389 Arguments are accessed within the user command via $arg0..$arg9. A
4392 print $arg0 + $arg1 + $arg2
4394 To execute the command use:
4397 Defines the command "adder" which prints the sum of its three arguments.
4398 Note the arguments are text substitutions, so they may reference variables,
4399 use complex expressions, or even perform inferior function calls.
4401 * New `if' and `while' commands
4403 This makes it possible to write more sophisticated user-defined
4404 commands. Both commands take a single argument, which is the
4405 expression to evaluate, and must be followed by the commands to
4406 execute, one per line, if the expression is nonzero, the list being
4407 terminated by the word `end'. The `if' command list may include an
4408 `else' word, which causes the following commands to be executed only
4409 if the expression is zero.
4411 * Fortran source language mode
4413 GDB now includes partial support for Fortran 77. It will recognize
4414 Fortran programs and can evaluate a subset of Fortran expressions, but
4415 variables and functions may not be handled correctly. GDB will work
4416 with G77, but does not yet know much about symbols emitted by other
4419 * Better HPUX support
4421 Most debugging facilities now work on dynamic executables for HPPAs
4422 running hpux9 or later. You can attach to running dynamically linked
4423 processes, but by default the dynamic libraries will be read-only, so
4424 for instance you won't be able to put breakpoints in them. To change
4425 that behavior do the following before running the program:
4431 This will cause the libraries to be mapped private and read-write.
4432 To revert to the normal behavior, do this:
4438 You cannot set breakpoints or examine data in the library until after
4439 the library is loaded if the function/data symbols do not have
4442 GDB can now also read debug symbols produced by the HP C compiler on
4443 HPPAs (sorry, no C++, Fortran or 68k support).
4445 * Target byte order now dynamically selectable
4447 You can choose which byte order to use with a target system, via the
4448 commands "set endian big" and "set endian little", and you can see the
4449 current setting by using "show endian". You can also give the command
4450 "set endian auto", in which case GDB will use the byte order
4451 associated with the executable. Currently, only embedded MIPS
4452 configurations support dynamic selection of target byte order.
4454 * New DOS host serial code
4456 This version uses DPMI interrupts to handle buffered I/O, so you
4457 no longer need to run asynctsr when debugging boards connected to
4460 *** Changes in GDB-4.13:
4462 * New "complete" command
4464 This lists all the possible completions for the rest of the line, if it
4465 were to be given as a command itself. This is intended for use by emacs.
4467 * Trailing space optional in prompt
4469 "set prompt" no longer adds a space for you after the prompt you set. This
4470 allows you to set a prompt which ends in a space or one that does not.
4472 * Breakpoint hit counts
4474 "info break" now displays a count of the number of times the breakpoint
4475 has been hit. This is especially useful in conjunction with "ignore"; you
4476 can ignore a large number of breakpoint hits, look at the breakpoint info
4477 to see how many times the breakpoint was hit, then run again, ignoring one
4478 less than that number, and this will get you quickly to the last hit of
4481 * Ability to stop printing at NULL character
4483 "set print null-stop" will cause GDB to stop printing the characters of
4484 an array when the first NULL is encountered. This is useful when large
4485 arrays actually contain only short strings.
4487 * Shared library breakpoints
4489 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4490 breakpoints in shared libraries before the executable is run.
4492 * Hardware watchpoints
4494 There is a new hardware breakpoint for the watch command for sparclite
4495 targets. See gdb/sparclite/hw_breakpoint.note.
4497 Hardware watchpoints are also now supported under GNU/Linux.
4501 Annotations have been added. These are for use with graphical interfaces,
4502 and are still experimental. Currently only gdba.el uses these.
4504 * Improved Irix 5 support
4506 GDB now works properly with Irix 5.2.
4508 * Improved HPPA support
4510 GDB now works properly with the latest GCC and GAS.
4512 * New native configurations
4514 Sequent PTX4 i[34]86-sequent-ptx4
4515 HPPA running OSF/1 hppa*-*-osf*
4516 Atari TT running SVR4 m68*-*-sysv4*
4517 RS/6000 LynxOS rs6000-*-lynxos*
4521 OS/9000 i[34]86-*-os9k
4522 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4525 * Hitachi SH7000 and E7000-PC ICE support
4527 There is now support for communicating with the Hitachi E7000-PC ICE.
4528 This is available automatically when GDB is configured for the SH.
4532 As usual, a variety of small fixes and improvements, both generic
4533 and configuration-specific. See the ChangeLog for more detail.
4535 *** Changes in GDB-4.12:
4537 * Irix 5 is now supported
4541 GDB-4.12 on the HPPA has a number of changes which make it unable
4542 to debug the output from the currently released versions of GCC and
4543 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4544 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4545 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4548 *** Changes in GDB-4.11:
4550 * User visible changes:
4554 The "set remotedebug" option is now consistent between the mips remote
4555 target, remote targets using the gdb-specific protocol, UDI (AMD's
4556 debug protocol for the 29k) and the 88k bug monitor. It is now an
4557 integer specifying a debug level (normally 0 or 1, but 2 means more
4558 debugging info for the mips target).
4560 * DEC Alpha native support
4562 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4563 debug info, but GDB works fairly well with the DEC compiler and should
4564 work with a future GCC release. See the README file for a few
4565 Alpha-specific notes.
4567 * Preliminary thread implementation
4569 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4571 * LynxOS native and target support for 386
4573 This release has been hosted on LynxOS 2.2, and also can be configured
4574 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4577 * Improvements in C++ mangling/demangling.
4579 This release has much better g++ debugging, specifically in name
4580 mangling/demangling, virtual function calls, print virtual table,
4581 call methods, ...etc.
4583 *** Changes in GDB-4.10:
4585 * User visible changes:
4587 Remote debugging using the GDB-specific (`target remote') protocol now
4588 supports the `load' command. This is only useful if you have some
4589 other way of getting the stub to the target system, and you can put it
4590 somewhere in memory where it won't get clobbered by the download.
4592 Filename completion now works.
4594 When run under emacs mode, the "info line" command now causes the
4595 arrow to point to the line specified. Also, "info line" prints
4596 addresses in symbolic form (as well as hex).
4598 All vxworks based targets now support a user settable option, called
4599 vxworks-timeout. This option represents the number of seconds gdb
4600 should wait for responses to rpc's. You might want to use this if
4601 your vxworks target is, perhaps, a slow software simulator or happens
4602 to be on the far side of a thin network line.
4606 This release contains support for using a DEC alpha as a GDB host for
4607 cross debugging. Native alpha debugging is not supported yet.
4610 *** Changes in GDB-4.9:
4614 This is the first GDB release which is accompanied by a matching testsuite.
4615 The testsuite requires installation of dejagnu, which should be available
4616 via ftp from most sites that carry GNU software.
4620 'Cfront' style demangling has had its name changed to 'ARM' style, to
4621 emphasize that it was written from the specifications in the C++ Annotated
4622 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4623 disclaimers, it still generated too much confusion with users attempting to
4624 use gdb with AT&T cfront.
4628 GDB now uses a standard remote interface to a simulator library.
4629 So far, the library contains simulators for the Zilog Z8001/2, the
4630 Hitachi H8/300, H8/500 and Super-H.
4632 * New targets supported
4634 H8/300 simulator h8300-hitachi-hms or h8300hms
4635 H8/500 simulator h8500-hitachi-hms or h8500hms
4636 SH simulator sh-hitachi-hms or sh
4637 Z8000 simulator z8k-zilog-none or z8ksim
4638 IDT MIPS board over serial line mips-idt-ecoff
4640 Cross-debugging to GO32 targets is supported. It requires a custom
4641 version of the i386-stub.c module which is integrated with the
4642 GO32 memory extender.
4644 * New remote protocols
4646 MIPS remote debugging protocol.
4648 * New source languages supported
4650 This version includes preliminary support for Chill, a Pascal like language
4651 used by telecommunications companies. Chill support is also being integrated
4652 into the GNU compiler, but we don't know when it will be publically available.
4655 *** Changes in GDB-4.8:
4657 * HP Precision Architecture supported
4659 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4660 version of this support was available as a set of patches from the
4661 University of Utah. GDB does not support debugging of programs
4662 compiled with the HP compiler, because HP will not document their file
4663 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4664 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4666 Many problems in the preliminary version have been fixed.
4668 * Faster and better demangling
4670 We have improved template demangling and fixed numerous bugs in the GNU style
4671 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4672 character types (wchar_t) are now supported. Demangling of each symbol is now
4673 only done once, and is cached when the symbol table for a file is read in.
4674 This results in a small increase in memory usage for C programs, a moderate
4675 increase in memory usage for C++ programs, and a fantastic speedup in
4678 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4679 from the specifications in the Annotated Reference Manual, which AT&T's
4680 compiler does not actually implement.
4682 * G++ multiple inheritance compiler problem
4684 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4685 inheritance lattices was reworked to properly discover ambiguities. We
4686 recently found an example which causes this new algorithm to fail in a
4687 very subtle way, producing bad debug information for those classes.
4688 The file 'gcc.patch' (in this directory) can be applied to gcc to
4689 circumvent the problem. A future GCC release will contain a complete
4692 The previous G++ debug info problem (mentioned below for the gdb-4.7
4693 release) is fixed in gcc version 2.3.2.
4695 * Improved configure script
4697 The `configure' script will now attempt to guess your system type if
4698 you don't supply a host system type. The old scheme of supplying a
4699 host system triplet is preferable over using this. All the magic is
4700 done in the new `config.guess' script. Examine it for details.
4702 We have also brought our configure script much more in line with the FSF's
4703 version. It now supports the --with-xxx options. In particular,
4704 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4705 The resulting GDB will not be able to read arbitrary object file formats --
4706 only the format ``expected'' to be used on the configured target system.
4707 We hope to make this the default in a future release.
4709 * Documentation improvements
4711 There's new internal documentation on how to modify GDB, and how to
4712 produce clean changes to the code. We implore people to read it
4713 before submitting changes.
4715 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4716 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4717 `info' files are also provided. To build `info' files from scratch,
4718 you will need the latest `makeinfo' release, which will be available in
4719 a future texinfo-X.Y release.
4721 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4722 We're not sure exactly which versions have this problem, but it has
4723 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4724 or better. If that isn't possible, there is a patch in
4725 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4726 around this problem.
4730 GDB now supports array constants that can be used in expressions typed in by
4731 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4732 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4735 The new directory `gdb/sparclite' contains a program that demonstrates
4736 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4738 * New native hosts supported
4740 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4741 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4743 * New targets supported
4745 AMD 29k family via UDI a29k-amd-udi or udi29k
4747 * New file formats supported
4749 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4750 HPUX core files, and SCO 3.2v2 core files.
4754 Attaching to processes now works again; thanks for the many bug reports.
4756 We have also stomped on a bunch of core dumps caused by
4757 printf_filtered("%s") problems.
4759 We eliminated a copyright problem on the rpc and ptrace header files
4760 for VxWorks, which was discovered at the last minute during the 4.7
4761 release. You should now be able to build a VxWorks GDB.
4763 You can now interrupt gdb while an attached process is running. This
4764 will cause the attached process to stop, and give control back to GDB.
4766 We fixed problems caused by using too many file descriptors
4767 for reading symbols from object files and libraries. This was
4768 especially a problem for programs that used many (~100) shared
4771 The `step' command now only enters a subroutine if there is line number
4772 information for the subroutine. Otherwise it acts like the `next'
4773 command. Previously, `step' would enter subroutines if there was
4774 any debugging information about the routine. This avoids problems
4775 when using `cc -g1' on MIPS machines.
4777 * Internal improvements
4779 GDB's internal interfaces have been improved to make it easier to support
4780 debugging of multiple languages in the future.
4782 GDB now uses a common structure for symbol information internally.
4783 Minimal symbols (derived from linkage symbols in object files), partial
4784 symbols (from a quick scan of debug information), and full symbols
4785 contain a common subset of information, making it easier to write
4786 shared code that handles any of them.
4788 * New command line options
4790 We now accept --silent as an alias for --quiet.
4794 The memory-mapped-malloc library is now licensed under the GNU Library
4795 General Public License.
4797 *** Changes in GDB-4.7:
4799 * Host/native/target split
4801 GDB has had some major internal surgery to untangle the support for
4802 hosts and remote targets. Now, when you configure GDB for a remote
4803 target, it will no longer load in all of the support for debugging
4804 local programs on the host. When fully completed and tested, this will
4805 ensure that arbitrary host/target combinations are possible.
4807 The primary conceptual shift is to separate the non-portable code in
4808 GDB into three categories. Host specific code is required any time GDB
4809 is compiled on that host, regardless of the target. Target specific
4810 code relates to the peculiarities of the target, but can be compiled on
4811 any host. Native specific code is everything else: it can only be
4812 built when the host and target are the same system. Child process
4813 handling and core file support are two common `native' examples.
4815 GDB's use of /proc for controlling Unix child processes is now cleaner.
4816 It has been split out into a single module under the `target_ops' vector,
4817 plus two native-dependent functions for each system that uses /proc.
4819 * New hosts supported
4821 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4822 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4823 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4825 * New targets supported
4827 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4828 68030 and CPU32 m68030-*-*, m68332-*-*
4830 * New native hosts supported
4832 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4833 (386bsd is not well tested yet)
4834 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4836 * New file formats supported
4838 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4839 supports reading of `a.out.adobe' object files, which are an a.out
4840 format extended with minimal information about multiple sections.
4844 `show copying' is the same as the old `info copying'.
4845 `show warranty' is the same as `info warrantee'.
4846 These were renamed for consistency. The old commands continue to work.
4848 `info handle' is a new alias for `info signals'.
4850 You can now define pre-command hooks, which attach arbitrary command
4851 scripts to any command. The commands in the hook will be executed
4852 prior to the user's command. You can also create a hook which will be
4853 executed whenever the program stops. See gdb.texinfo.
4857 We now deal with Cfront style name mangling, and can even extract type
4858 info from mangled symbols. GDB can automatically figure out which
4859 symbol mangling style your C++ compiler uses.
4861 Calling of methods and virtual functions has been improved as well.
4865 The crash that occured when debugging Sun Ansi-C compiled binaries is
4866 fixed. This was due to mishandling of the extra N_SO stabs output
4869 We also finally got Ultrix 4.2 running in house, and fixed core file
4870 support, with help from a dozen people on the net.
4872 John M. Farrell discovered that the reason that single-stepping was so
4873 slow on all of the Mips based platforms (primarily SGI and DEC) was
4874 that we were trying to demangle and lookup a symbol used for internal
4875 purposes on every instruction that was being stepped through. Changing
4876 the name of that symbol so that it couldn't be mistaken for a C++
4877 mangled symbol sped things up a great deal.
4879 Rich Pixley sped up symbol lookups in general by getting much smarter
4880 about when C++ symbol mangling is necessary. This should make symbol
4881 completion (TAB on the command line) much faster. It's not as fast as
4882 we'd like, but it's significantly faster than gdb-4.6.
4886 A new user controllable variable 'call_scratch_address' can
4887 specify the location of a scratch area to be used when GDB
4888 calls a function in the target. This is necessary because the
4889 usual method of putting the scratch area on the stack does not work
4890 in systems that have separate instruction and data spaces.
4892 We integrated changes to support the 29k UDI (Universal Debugger
4893 Interface), but discovered at the last minute that we didn't have all
4894 of the appropriate copyright paperwork. We are working with AMD to
4895 resolve this, and hope to have it available soon.
4899 We have sped up the remote serial line protocol, especially for targets
4900 with lots of registers. It now supports a new `expedited status' ('T')
4901 message which can be used in place of the existing 'S' status message.
4902 This allows the remote stub to send only the registers that GDB
4903 needs to make a quick decision about single-stepping or conditional
4904 breakpoints, eliminating the need to fetch the entire register set for
4905 each instruction being stepped through.
4907 The GDB remote serial protocol now implements a write-through cache for
4908 registers, only re-reading the registers if the target has run.
4910 There is also a new remote serial stub for SPARC processors. You can
4911 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4912 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4913 processor with a serial port.
4917 Configure.in files have become much easier to read and modify. A new
4918 `table driven' format makes it more obvious what configurations are
4919 supported, and what files each one uses.
4923 There is a new opcodes library which will eventually contain all of the
4924 disassembly routines and opcode tables. At present, it only contains
4925 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4926 disassembler (binutils/objdump) to share these routines.
4928 The libiberty library is now copylefted under the GNU Library General
4929 Public License. This allows more liberal use, and was done so libg++
4930 can use it. This makes no difference to GDB, since the Library License
4931 grants all the rights from the General Public License.
4935 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4936 reference to the stabs symbol info used by the debugger. It is (as far
4937 as we know) the only published document on this fascinating topic. We
4938 encourage you to read it, compare it to the stabs information on your
4939 system, and send improvements on the document in general (to
4940 bug-gdb@prep.ai.mit.edu).
4942 And, of course, many bugs have been fixed.
4945 *** Changes in GDB-4.6:
4947 * Better support for C++ function names
4949 GDB now accepts as input the "demangled form" of C++ overloaded function
4950 names and member function names, and can do command completion on such names
4951 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4952 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4953 Make use of command completion, it is your friend.
4955 GDB also now accepts a variety of C++ mangled symbol formats. They are
4956 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4957 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4958 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4959 for the list of formats.
4961 * G++ symbol mangling problem
4963 Recent versions of gcc have a bug in how they emit debugging information for
4964 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4965 directory) can be applied to gcc to fix the problem. Alternatively, if you
4966 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4967 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4968 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4971 * New 'maintenance' command
4973 All of the commands related to hacking GDB internals have been moved out of
4974 the main command set, and now live behind the 'maintenance' command. This
4975 can also be abbreviated as 'mt'. The following changes were made:
4977 dump-me -> maintenance dump-me
4978 info all-breakpoints -> maintenance info breakpoints
4979 printmsyms -> maintenance print msyms
4980 printobjfiles -> maintenance print objfiles
4981 printpsyms -> maintenance print psymbols
4982 printsyms -> maintenance print symbols
4984 The following commands are new:
4986 maintenance demangle Call internal GDB demangler routine to
4987 demangle a C++ link name and prints the result.
4988 maintenance print type Print a type chain for a given symbol
4990 * Change to .gdbinit file processing
4992 We now read the $HOME/.gdbinit file before processing the argv arguments
4993 (e.g. reading symbol files or core files). This allows global parameters to
4994 be set, which will apply during the symbol reading. The ./.gdbinit is still
4995 read after argv processing.
4997 * New hosts supported
4999 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5001 GNU/Linux support i386-unknown-linux or linux
5003 We are also including code to support the HP/PA running BSD and HPUX. This
5004 is almost guaranteed not to work, as we didn't have time to test or build it
5005 for this release. We are including it so that the more adventurous (or
5006 masochistic) of you can play with it. We also had major problems with the
5007 fact that the compiler that we got from HP doesn't support the -g option.
5010 * New targets supported
5012 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5014 * More smarts about finding #include files
5016 GDB now remembers the compilation directory for all include files, and for
5017 all files from which C is generated (like yacc and lex sources). This
5018 greatly improves GDB's ability to find yacc/lex sources, and include files,
5019 especially if you are debugging your program from a directory different from
5020 the one that contains your sources.
5022 We also fixed a bug which caused difficulty with listing and setting
5023 breakpoints in include files which contain C code. (In the past, you had to
5024 try twice in order to list an include file that you hadn't looked at before.)
5026 * Interesting infernals change
5028 GDB now deals with arbitrary numbers of sections, where the symbols for each
5029 section must be relocated relative to that section's landing place in the
5030 target's address space. This work was needed to support ELF with embedded
5031 stabs used by Solaris-2.0.
5033 * Bug fixes (of course!)
5035 There have been loads of fixes for the following things:
5036 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5037 i960, stabs, DOS(GO32), procfs, etc...
5039 See the ChangeLog for details.
5041 *** Changes in GDB-4.5:
5043 * New machines supported (host and target)
5045 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5047 SGI Irix-4.x mips-sgi-irix4 or iris4
5049 * New malloc package
5051 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5052 Mmalloc is capable of handling mutiple heaps of memory. It is also
5053 capable of saving a heap to a file, and then mapping it back in later.
5054 This can be used to greatly speedup the startup of GDB by using a
5055 pre-parsed symbol table which lives in a mmalloc managed heap. For
5056 more details, please read mmalloc/mmalloc.texi.
5060 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5061 'help info proc' for details.
5063 * MIPS ecoff symbol table format
5065 The code that reads MIPS symbol table format is now supported on all hosts.
5066 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5069 * File name changes for MS-DOS
5071 Many files in the config directories have been renamed to make it easier to
5072 support GDB on MS-DOSe systems (which have very restrictive file name
5073 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5074 environment) is close to working but has some remaining problems. Note
5075 that debugging of DOS programs is not supported, due to limitations
5076 in the ``operating system'', but it can be used to host cross-debugging.
5078 * Cross byte order fixes
5080 Many fixes have been made to support cross debugging of Sparc and MIPS
5081 targets from hosts whose byte order differs.
5083 * New -mapped and -readnow options
5085 If memory-mapped files are available on your system through the 'mmap'
5086 system call, you can use the -mapped option on the `file' or
5087 `symbol-file' commands to cause GDB to write the symbols from your
5088 program into a reusable file. If the program you are debugging is
5089 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5090 Future GDB debugging sessions will notice the presence of this file,
5091 and will quickly map in symbol information from it, rather than reading
5092 the symbol table from the executable program. Using the '-mapped'
5093 option in a GDB `file' or `symbol-file' command has the same effect as
5094 starting GDB with the '-mapped' command-line option.
5096 You can cause GDB to read the entire symbol table immediately by using
5097 the '-readnow' option with any of the commands that load symbol table
5098 information (or on the GDB command line). This makes the command
5099 slower, but makes future operations faster.
5101 The -mapped and -readnow options are typically combined in order to
5102 build a `fred.syms' file that contains complete symbol information.
5103 A simple GDB invocation to do nothing but build a `.syms' file for future
5106 gdb -batch -nx -mapped -readnow programname
5108 The `.syms' file is specific to the host machine on which GDB is run.
5109 It holds an exact image of GDB's internal symbol table. It cannot be
5110 shared across multiple host platforms.
5112 * longjmp() handling
5114 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5115 siglongjmp() without losing control. This feature has not yet been ported to
5116 all systems. It currently works on many 386 platforms, all MIPS-based
5117 platforms (SGI, DECstation, etc), and Sun3/4.
5121 Preliminary work has been put in to support the new Solaris OS from Sun. At
5122 this time, it can control and debug processes, but it is not capable of
5127 As always, many many bug fixes. The major areas were with g++, and mipsread.
5128 People using the MIPS-based platforms should experience fewer mysterious
5129 crashes and trashed symbol tables.
5131 *** Changes in GDB-4.4:
5133 * New machines supported (host and target)
5135 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5137 BSD Reno on Vax vax-dec-bsd
5138 Ultrix on Vax vax-dec-ultrix
5140 * New machines supported (target)
5142 AMD 29000 embedded, using EBMON a29k-none-none
5146 GDB continues to improve its handling of C++. `References' work better.
5147 The demangler has also been improved, and now deals with symbols mangled as
5148 per the Annotated C++ Reference Guide.
5150 GDB also now handles `stabs' symbol information embedded in MIPS
5151 `ecoff' symbol tables. Since the ecoff format was not easily
5152 extensible to handle new languages such as C++, this appeared to be a
5153 good way to put C++ debugging info into MIPS binaries. This option
5154 will be supported in the GNU C compiler, version 2, when it is
5157 * New features for SVR4
5159 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5160 shared libraries. Debugging dynamically linked programs should present
5161 only minor differences from debugging statically linked programs.
5163 The `info proc' command will print out information about any process
5164 on an SVR4 system (including the one you are debugging). At the moment,
5165 it prints the address mappings of the process.
5167 If you bring up GDB on another SVR4 system, please send mail to
5168 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5170 * Better dynamic linking support in SunOS
5172 Reading symbols from shared libraries which contain debugging symbols
5173 now works properly. However, there remain issues such as automatic
5174 skipping of `transfer vector' code during function calls, which
5175 make it harder to debug code in a shared library, than to debug the
5176 same code linked statically.
5180 GDB is now using the latest `getopt' routines from the FSF. This
5181 version accepts the -- prefix for options with long names. GDB will
5182 continue to accept the old forms (-option and +option) as well.
5183 Various single letter abbreviations for options have been explicity
5184 added to the option table so that they won't get overshadowed in the
5185 future by other options that begin with the same letter.
5189 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5190 Many assorted bugs have been handled. Many more remain to be handled.
5191 See the various ChangeLog files (primarily in gdb and bfd) for details.
5194 *** Changes in GDB-4.3:
5196 * New machines supported (host and target)
5198 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5199 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5200 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5202 * Almost SCO Unix support
5204 We had hoped to support:
5205 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5206 (except for core file support), but we discovered very late in the release
5207 that it has problems with process groups that render gdb unusable. Sorry
5208 about that. I encourage people to fix it and post the fixes.
5210 * Preliminary ELF and DWARF support
5212 GDB can read ELF object files on System V Release 4, and can handle
5213 debugging records for C, in DWARF format, in ELF files. This support
5214 is preliminary. If you bring up GDB on another SVR4 system, please
5215 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5220 GDB now uses the latest `readline' library. One user-visible change
5221 is that two tabs will list possible command completions, which previously
5222 required typing M-? (meta-question mark, or ESC ?).
5226 The `stepi' bug that many of you noticed has been squashed.
5227 Many bugs in C++ have been handled. Many more remain to be handled.
5228 See the various ChangeLog files (primarily in gdb and bfd) for details.
5230 * State of the MIPS world (in case you wondered):
5232 GDB can understand the symbol tables emitted by the compilers
5233 supplied by most vendors of MIPS-based machines, including DEC. These
5234 symbol tables are in a format that essentially nobody else uses.
5236 Some versions of gcc come with an assembler post-processor called
5237 mips-tfile. This program is required if you want to do source-level
5238 debugging of gcc-compiled programs. I believe FSF does not ship
5239 mips-tfile with gcc version 1, but it will eventually come with gcc
5242 Debugging of g++ output remains a problem. g++ version 1.xx does not
5243 really support it at all. (If you're lucky, you should be able to get
5244 line numbers and stack traces to work, but no parameters or local
5245 variables.) With some work it should be possible to improve the
5248 When gcc version 2 is released, you will have somewhat better luck.
5249 However, even then you will get confusing results for inheritance and
5252 We will eventually provide full debugging of g++ output on
5253 DECstations. This will probably involve some kind of stabs-in-ecoff
5254 encapulation, but the details have not been worked out yet.
5257 *** Changes in GDB-4.2:
5259 * Improved configuration
5261 Only one copy of `configure' exists now, and it is not self-modifying.
5262 Porting BFD is simpler.
5266 The `step' and `next' commands now only stop at the first instruction
5267 of a source line. This prevents the multiple stops that used to occur
5268 in switch statements, for-loops, etc. `Step' continues to stop if a
5269 function that has debugging information is called within the line.
5273 Lots of small bugs fixed. More remain.
5275 * New host supported (not target)
5277 Intel 386 PC clone running Mach i386-none-mach
5280 *** Changes in GDB-4.1:
5282 * Multiple source language support
5284 GDB now has internal scaffolding to handle several source languages.
5285 It determines the type of each source file from its filename extension,
5286 and will switch expression parsing and number formatting to match the
5287 language of the function in the currently selected stack frame.
5288 You can also specifically set the language to be used, with
5289 `set language c' or `set language modula-2'.
5293 GDB now has preliminary support for the GNU Modula-2 compiler,
5294 currently under development at the State University of New York at
5295 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5296 continue through the fall of 1991 and into 1992.
5298 Other Modula-2 compilers are currently not supported, and attempting to
5299 debug programs compiled with them will likely result in an error as the
5300 symbol table is read. Feel free to work on it, though!
5302 There are hooks in GDB for strict type checking and range checking,
5303 in the `Modula-2 philosophy', but they do not currently work.
5307 GDB can now write to executable and core files (e.g. patch
5308 a variable's value). You must turn this switch on, specify
5309 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5310 by assigning a new value to a variable. Modifications take
5313 * Automatic SunOS shared library reading
5315 When you run your program, GDB automatically determines where its
5316 shared libraries (if any) have been loaded, and reads their symbols.
5317 The `share' command is no longer needed. This also works when
5318 examining core files.
5322 You can specify the number of lines that the `list' command shows.
5325 * New machines supported (host and target)
5327 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5328 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5329 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5331 * New hosts supported (not targets)
5333 IBM RT/PC: romp-ibm-aix or rtpc
5335 * New targets supported (not hosts)
5337 AMD 29000 embedded with COFF a29k-none-coff
5338 AMD 29000 embedded with a.out a29k-none-aout
5339 Ultracomputer remote kernel debug a29k-nyu-kern
5341 * New remote interfaces
5347 *** Changes in GDB-4.0:
5351 Wide output is wrapped at good places to make the output more readable.
5353 Gdb now supports cross-debugging from a host machine of one type to a
5354 target machine of another type. Communication with the target system
5355 is over serial lines. The ``target'' command handles connecting to the
5356 remote system; the ``load'' command will download a program into the
5357 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5358 also supports debugging of realtime processes running under VxWorks,
5359 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5360 stub on the target system.
5362 New CPUs supported include the AMD 29000 and Intel 960.
5364 GDB now reads object files and symbol tables via a ``binary file''
5365 library, which allows a single copy of GDB to debug programs of multiple
5366 object file types such as a.out and coff.
5368 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5369 refcard.dvi and refcard.ps are available to format it).
5372 * Control-Variable user interface simplified
5374 All variables that control the operation of the debugger can be set
5375 by the ``set'' command, and displayed by the ``show'' command.
5377 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5378 ``Show prompt'' produces the response:
5379 Gdb's prompt is new-gdb=>.
5381 What follows are the NEW set commands. The command ``help set'' will
5382 print a complete list of old and new set commands. ``help set FOO''
5383 will give a longer description of the variable FOO. ``show'' will show
5384 all of the variable descriptions and their current settings.
5386 confirm on/off: Enables warning questions for operations that are
5387 hard to recover from, e.g. rerunning the program while
5388 it is already running. Default is ON.
5390 editing on/off: Enables EMACS style command line editing
5391 of input. Previous lines can be recalled with
5392 control-P, the current line can be edited with control-B,
5393 you can search for commands with control-R, etc.
5396 history filename NAME: NAME is where the gdb command history
5397 will be stored. The default is .gdb_history,
5398 or the value of the environment variable
5401 history size N: The size, in commands, of the command history. The
5402 default is 256, or the value of the environment variable
5405 history save on/off: If this value is set to ON, the history file will
5406 be saved after exiting gdb. If set to OFF, the
5407 file will not be saved. The default is OFF.
5409 history expansion on/off: If this value is set to ON, then csh-like
5410 history expansion will be performed on
5411 command line input. The default is OFF.
5413 radix N: Sets the default radix for input and output. It can be set
5414 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5415 in the current radix, so "set radix 10" is always a no-op.
5417 height N: This integer value is the number of lines on a page. Default
5418 is 24, the current `stty rows'' setting, or the ``li#''
5419 setting from the termcap entry matching the environment
5422 width N: This integer value is the number of characters on a line.
5423 Default is 80, the current `stty cols'' setting, or the ``co#''
5424 setting from the termcap entry matching the environment
5427 Note: ``set screensize'' is obsolete. Use ``set height'' and
5428 ``set width'' instead.
5430 print address on/off: Print memory addresses in various command displays,
5431 such as stack traces and structure values. Gdb looks
5432 more ``symbolic'' if you turn this off; it looks more
5433 ``machine level'' with it on. Default is ON.
5435 print array on/off: Prettyprint arrays. New convenient format! Default
5438 print demangle on/off: Print C++ symbols in "source" form if on,
5441 print asm-demangle on/off: Same, for assembler level printouts
5444 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5447 * Support for Epoch Environment.
5449 The epoch environment is a version of Emacs v18 with windowing. One
5450 new command, ``inspect'', is identical to ``print'', except that if you
5451 are running in the epoch environment, the value is printed in its own
5455 * Support for Shared Libraries
5457 GDB can now debug programs and core files that use SunOS shared libraries.
5458 Symbols from a shared library cannot be referenced
5459 before the shared library has been linked with the program (this
5460 happens after you type ``run'' and before the function main() is entered).
5461 At any time after this linking (including when examining core files
5462 from dynamically linked programs), gdb reads the symbols from each
5463 shared library when you type the ``sharedlibrary'' command.
5464 It can be abbreviated ``share''.
5466 sharedlibrary REGEXP: Load shared object library symbols for files
5467 matching a unix regular expression. No argument
5468 indicates to load symbols for all shared libraries.
5470 info sharedlibrary: Status of loaded shared libraries.
5475 A watchpoint stops execution of a program whenever the value of an
5476 expression changes. Checking for this slows down execution
5477 tremendously whenever you are in the scope of the expression, but is
5478 quite useful for catching tough ``bit-spreader'' or pointer misuse
5479 problems. Some machines such as the 386 have hardware for doing this
5480 more quickly, and future versions of gdb will use this hardware.
5482 watch EXP: Set a watchpoint (breakpoint) for an expression.
5484 info watchpoints: Information about your watchpoints.
5486 delete N: Deletes watchpoint number N (same as breakpoints).
5487 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5488 enable N: Re-enables watchpoint number N (same as breakpoints).
5491 * C++ multiple inheritance
5493 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5496 * C++ exception handling
5498 Gdb now supports limited C++ exception handling. Besides the existing
5499 ability to breakpoint on an exception handler, gdb can breakpoint on
5500 the raising of an exception (before the stack is peeled back to the
5503 catch FOO: If there is a FOO exception handler in the dynamic scope,
5504 set a breakpoint to catch exceptions which may be raised there.
5505 Multiple exceptions (``catch foo bar baz'') may be caught.
5507 info catch: Lists all exceptions which may be caught in the
5508 current stack frame.
5511 * Minor command changes
5513 The command ``call func (arg, arg, ...)'' now acts like the print
5514 command, except it does not print or save a value if the function's result
5515 is void. This is similar to dbx usage.
5517 The ``up'' and ``down'' commands now always print the frame they end up
5518 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5519 frames without printing.
5521 * New directory command
5523 'dir' now adds directories to the FRONT of the source search path.
5524 The path starts off empty. Source files that contain debug information
5525 about the directory in which they were compiled can be found even
5526 with an empty path; Sun CC and GCC include this information. If GDB can't
5527 find your source file in the current directory, type "dir .".
5529 * Configuring GDB for compilation
5531 For normal use, type ``./configure host''. See README or gdb.texinfo
5534 GDB now handles cross debugging. If you are remotely debugging between
5535 two different machines, type ``./configure host -target=targ''.
5536 Host is the machine where GDB will run; targ is the machine
5537 where the program that you are debugging will run.