1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.6
6 * GDB now supports Fission DWP file format version 2.
7 http://gcc.gnu.org/wiki/DebugFission
9 * New convenience function "$_isvoid", to check whether an expression
10 is void. A void expression is an expression where the type of the
11 result is "void". For example, some convenience variables may be
12 "void" when evaluated (e.g., "$_exitcode" before the execution of
13 the program being debugged; or an undefined convenience variable).
14 Another example, when calling a function whose return type is
17 * The "maintenance print objfiles" command now takes an optional regexp.
19 * The "catch syscall" command now works on arm*-linux* targets.
21 * GDB now consistently shows "<not saved>" when printing values of
22 registers the debug info indicates have not been saved in the frame
23 and there's nowhere to retrieve them from
24 (callee-saved/call-clobbered registers):
29 (gdb) info registers rax
32 Before, the former would print "<optimized out>", and the latter
33 "*value not available*".
37 ** Frame filters and frame decorators have been added.
38 ** Temporary breakpoints are now supported.
42 Nios II ELF nios2*-*-elf
43 Nios II GNU/Linux nios2*-*-linux
44 Texas Instruments MSP430 msp430*-*-elf
46 * Removed native configurations
48 Support for these a.out NetBSD and OpenBSD obsolete configurations has
49 been removed. ELF variants of these configurations are kept supported.
51 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
52 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
53 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
54 i[34567]86-*-openbsd3.[0-3]
55 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
56 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
57 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
61 Like "catch throw", but catches a re-thrown exception.
63 Renamed from old "maint check-symtabs".
65 Perform consistency checks on symtabs.
67 Expand symtabs matching an optional regexp.
70 Display the details of GDB configure-time options.
72 maint set|show per-command
73 maint set|show per-command space
74 maint set|show per-command time
75 maint set|show per-command symtab
76 Enable display of per-command gdb resource usage.
78 remove-symbol-file FILENAME
79 remove-symbol-file -a ADDRESS
80 Remove a symbol file added via add-symbol-file. The file to remove
81 can be identified by its filename or by an address that lies within
82 the boundaries of this symbol file in memory.
86 set debug symfile off|on
88 Control display of debugging info regarding reading symbol files and
89 symbol tables within those files
91 set print raw frame-arguments
92 show print raw frame-arguments
93 Set/show whether to print frame arguments in raw mode,
94 disregarding any defined pretty-printers.
96 set remote trace-status-packet
97 show remote trace-status-packet
98 Set/show the use of remote protocol qTStatus packet.
102 Control display of debugging messages related to Nios II targets.
106 Control whether target-assisted range stepping is enabled.
108 set startup-with-shell
109 show startup-with-shell
110 Specifies whether Unix child processes are started via a shell or
113 * You can now use a literal value 'unlimited' for options that
114 interpret 0 or -1 as meaning "unlimited". E.g., "set
115 trace-buffer-size unlimited" is now an alias for "set
116 trace-buffer-size -1" and "set height unlimited" is now an alias for
119 * New command-line options
121 Display the details of GDB configure-time options.
123 * The command 'tsave' can now support new option '-ctf' to save trace
124 buffer in Common Trace Format.
126 * Newly installed $prefix/bin/gcore acts as a shell interface for the
129 * GDB now implements the the C++ 'typeid' operator.
131 * The new convenience variable $_exception holds the exception being
132 thrown or caught at an exception-related catchpoint.
134 * The exception-related catchpoints, like "catch throw", now accept a
135 regular expression which can be used to filter exceptions by type.
137 * The new convenience variable $_exitsignal is automatically set to
138 the terminating signal number when the program being debugged dies
139 due to an uncaught signal.
143 ** The -trace-save MI command can optionally save trace buffer in Common
146 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
148 ** The command -data-list-register-values now accepts an optional
149 "--skip-unavailable" option. When used, only the available registers
152 ** The new command -trace-frame-collected dumps collected variables,
153 computed expressions, tvars, memory and registers in a traceframe.
155 ** The commands -stack-list-locals, -stack-list-arguments and
156 -stack-list-variables now accept an option "--skip-unavailable".
157 When used, only the available locals or arguments are displayed.
159 ** The -exec-run command now accepts an optional "--start" option.
160 When used, the command follows the same semantics as the "start"
161 command, stopping the program's execution at the start of its
164 ** The new commands -catch-assert and -catch-exceptions insert
165 catchpoints stopping the program when Ada exceptions are raised.
167 * New system-wide configuration scripts
168 A GDB installation now provides scripts suitable for use as system-wide
169 configuration scripts for the following systems:
173 * GDB now supports target-assigned range stepping with remote targets.
174 This improves the performance of stepping source lines by reducing
175 the number of control packets from/to GDB. See "New remote packets"
178 * GDB now understands the element 'tvar' in the XML traceframe info.
179 It has the id of the collected trace state variables.
181 * On S/390 targets that provide the transactional-execution feature,
182 the program interruption transaction diagnostic block (TDB) is now
183 represented as a number of additional "registers" in GDB.
189 The vCont packet supports a new 'r' action, that tells the remote
190 stub to step through an address range itself, without GDB
191 involvemement at each single-step.
193 qXfer:libraries-svr4:read's annex
194 The previously unused annex of the qXfer:libraries-svr4:read packet
195 is now used to support passing an argument list. The remote stub
196 reports support for this argument list to GDB's qSupported query.
197 The defined arguments are "start" and "prev", used to reduce work
198 necessary for library list updating, resulting in significant
201 * New features in the GDB remote stub, GDBserver
203 ** GDBserver now supports target-assisted range stepping. Currently
204 enabled on x86/x86_64 GNU/Linux targets.
206 ** GDBserver now adds element 'tvar' in the XML in the reply to
207 'qXfer:traceframe-info:read'. It has the id of the collected
208 trace state variables.
210 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
213 * New 'z' formatter for printing and examining memory, this displays the
214 value as hexadecimal zero padded on the left to the size of the type.
216 * GDB can now use Windows x64 unwinding data.
218 * The "set remotebaud" command has been replaced by "set serial baud".
219 Similarly, "show remotebaud" has been replaced by "show serial baud".
220 The "set remotebaud" and "show remotebaud" commands are still available
221 to provide backward compatibility with older versions of GDB.
223 *** Changes in GDB 7.6
225 * Target record has been renamed to record-full.
226 Record/replay is now enabled with the "record full" command.
227 This also affects settings that are associated with full record/replay
228 that have been moved from "set/show record" to "set/show record full":
230 set|show record full insn-number-max
231 set|show record full stop-at-limit
232 set|show record full memory-query
234 * A new record target "record-btrace" has been added. The new target
235 uses hardware support to record the control-flow of a process. It
236 does not support replaying the execution, but it implements the
237 below new commands for investigating the recorded execution log.
238 This new recording method can be enabled using:
242 The "record-btrace" target is only available on Intel Atom processors
243 and requires a Linux kernel 2.6.32 or later.
245 * Two new commands have been added for record/replay to give information
246 about the recorded execution without having to replay the execution.
247 The commands are only supported by "record btrace".
249 record instruction-history prints the execution history at
250 instruction granularity
252 record function-call-history prints the execution history at
255 * New native configurations
257 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
258 FreeBSD/powerpc powerpc*-*-freebsd
259 x86_64/Cygwin x86_64-*-cygwin*
260 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
264 ARM AArch64 aarch64*-*-elf
265 ARM AArch64 GNU/Linux aarch64*-*-linux
266 Lynx 178 PowerPC powerpc-*-lynx*178
267 x86_64/Cygwin x86_64-*-cygwin*
268 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
270 * If the configured location of system.gdbinit file (as given by the
271 --with-system-gdbinit option at configure time) is in the
272 data-directory (as specified by --with-gdb-datadir at configure
273 time) or in one of its subdirectories, then GDB will look for the
274 system-wide init file in the directory specified by the
275 --data-directory command-line option.
277 * New command line options:
279 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
280 other initialization files, unlike -nx which disables all of them.
282 * Removed command line options
284 -epoch This was used by the gdb mode in Epoch, an ancient fork of
287 * The 'ptype' and 'whatis' commands now accept an argument to control
290 * 'info proc' now works on some core files.
294 ** Vectors can be created with gdb.Type.vector.
296 ** Python's atexit.register now works in GDB.
298 ** Types can be pretty-printed via a Python API.
300 ** Python 3 is now supported (in addition to Python 2.4 or later)
302 ** New class gdb.Architecture exposes GDB's internal representation
303 of architecture in the Python API.
305 ** New method Frame.architecture returns the gdb.Architecture object
306 corresponding to the frame's architecture.
308 * New Python-based convenience functions:
310 ** $_memeq(buf1, buf2, length)
311 ** $_streq(str1, str2)
313 ** $_regex(str, regex)
315 * The 'cd' command now defaults to using '~' (the home directory) if not
318 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
319 default for GCC since November 2000.
321 * The command 'forward-search' can now be abbreviated as 'fo'.
323 * The command 'info tracepoints' can now display 'installed on target'
324 or 'not installed on target' for each non-pending location of tracepoint.
326 * New configure options
328 --enable-libmcheck/--disable-libmcheck
329 By default, development versions are built with -lmcheck on hosts
330 that support it, in order to help track memory corruption issues.
331 Release versions, on the other hand, are built without -lmcheck
332 by default. The --enable-libmcheck/--disable-libmcheck configure
333 options allow the user to override that default.
334 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
335 This configure option allows the user to build GDB with
336 libbabeltrace using which GDB can read Common Trace Format data.
338 * New commands (for set/show, see "New options" below)
341 Catch signals. This is similar to "handle", but allows commands and
342 conditions to be attached.
345 List the BFDs known to GDB.
347 python-interactive [command]
349 Start a Python interactive prompt, or evaluate the optional command
350 and print the result of expressions.
353 "py" is a new alias for "python".
355 enable type-printer [name]...
356 disable type-printer [name]...
357 Enable or disable type printers.
361 ** For the Renesas Super-H architecture, the "regs" command has been removed
362 (has been deprecated in GDB 7.5), and "info all-registers" should be used
367 set print type methods (on|off)
368 show print type methods
369 Control whether method declarations are displayed by "ptype".
370 The default is to show them.
372 set print type typedefs (on|off)
373 show print type typedefs
374 Control whether typedef definitions are displayed by "ptype".
375 The default is to show them.
377 set filename-display basename|relative|absolute
378 show filename-display
379 Control the way in which filenames is displayed.
380 The default is "relative", which preserves previous behavior.
382 set trace-buffer-size
383 show trace-buffer-size
384 Request target to change the size of trace buffer.
386 set remote trace-buffer-size-packet auto|on|off
387 show remote trace-buffer-size-packet
388 Control the use of the remote protocol `QTBuffer:size' packet.
392 Control display of debugging messages related to ARM AArch64.
395 set debug coff-pe-read
396 show debug coff-pe-read
397 Control display of debugging messages related to reading of COFF/PE
402 Control display of debugging messages related to Mach-O symbols
405 set debug notification
406 show debug notification
407 Control display of debugging info for async remote notification.
411 ** Command parameter changes are now notified using new async record
412 "=cmd-param-changed".
413 ** Trace frame changes caused by command "tfind" are now notified using
414 new async record "=traceframe-changed".
415 ** The creation, deletion and modification of trace state variables
416 are now notified using new async records "=tsv-created",
417 "=tsv-deleted" and "=tsv-modified".
418 ** The start and stop of process record are now notified using new
419 async record "=record-started" and "=record-stopped".
420 ** Memory changes are now notified using new async record
422 ** The data-disassemble command response will include a "fullname" field
423 containing the absolute file name when source has been requested.
424 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
425 command, to allow pattern filling of memory areas.
426 ** New commands "-catch-load"/"-catch-unload" added for intercepting
427 library load/unload events.
428 ** The response to breakpoint commands and breakpoint async records
429 includes an "installed" field containing a boolean state about each
430 non-pending tracepoint location is whether installed on target or not.
431 ** Output of the "-trace-status" command includes a "trace-file" field
432 containing the name of the trace file being examined. This field is
433 optional, and only present when examining a trace file.
434 ** The "fullname" field is now always present along with the "file" field,
435 even if the file cannot be found by GDB.
437 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
438 You must have the LZMA library available when configuring GDB for this
439 feature to be enabled. For more information, see:
440 http://fedoraproject.org/wiki/Features/MiniDebugInfo
445 Set the size of trace buffer. The remote stub reports support for this
446 packet to gdb's qSupported query.
449 Enable Branch Trace Store (BTS)-based branch tracing for the current
450 thread. The remote stub reports support for this packet to gdb's
454 Disable branch tracing for the current thread. The remote stub reports
455 support for this packet to gdb's qSupported query.
458 Read the traced branches for the current thread. The remote stub
459 reports support for this packet to gdb's qSupported query.
461 *** Changes in GDB 7.5
463 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
464 for more x32 ABI info.
466 * GDB now supports access to MIPS DSP registers on Linux targets.
468 * GDB now supports debugging microMIPS binaries.
470 * The "info os" command on GNU/Linux can now display information on
471 several new classes of objects managed by the operating system:
472 "info os procgroups" lists process groups
473 "info os files" lists file descriptors
474 "info os sockets" lists internet-domain sockets
475 "info os shm" lists shared-memory regions
476 "info os semaphores" lists semaphores
477 "info os msg" lists message queues
478 "info os modules" lists loaded kernel modules
480 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
481 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
482 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
483 options and inspect the probe arguments using the new $_probe_arg family
484 of convenience variables. You can obtain more information about SystemTap
485 in <http://sourceware.org/systemtap/>.
487 * GDB now supports reversible debugging on ARM, it allows you to
488 debug basic ARM and THUMB instructions, and provides
489 record/replay support.
491 * The option "symbol-reloading" has been deleted as it is no longer used.
495 ** GDB commands implemented in Python can now be put in command class
498 ** The "maint set python print-stack on|off" is now deleted.
500 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
501 apply "flag enum"-style pretty-printing to any enum.
503 ** gdb.lookup_symbol can now work when there is no current frame.
505 ** gdb.Symbol now has a 'line' attribute, holding the line number in
506 the source at which the symbol was defined.
508 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
509 method 'value'. The former indicates whether the symbol needs a
510 frame in order to compute its value, and the latter computes the
513 ** A new method 'referenced_value' on gdb.Value objects which can
514 dereference pointer as well as C++ reference values.
516 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
517 which return the global and static blocks (as gdb.Block objects),
518 of the underlying symbol table, respectively.
520 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
521 object associated with a PC value.
523 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
524 of the address range occupied by code for the current source line.
526 * Go language support.
527 GDB now supports debugging programs written in the Go programming
530 * GDBserver now supports stdio connections.
531 E.g. (gdb) target remote | ssh myhost gdbserver - hello
533 * The binary "gdbtui" can no longer be built or installed.
534 Use "gdb -tui" instead.
536 * GDB will now print "flag" enums specially. A flag enum is one where
537 all the enumerator values have no bits in common when pairwise
538 "and"ed. When printing a value whose type is a flag enum, GDB will
539 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
540 (gdb) print (enum E) 3
543 * The filename part of a linespec will now match trailing components
544 of a source file name. For example, "break gcc/expr.c:1000" will
545 now set a breakpoint in build/gcc/expr.c, but not
548 * The "info proc" and "generate-core-file" commands will now also
549 work on remote targets connected to GDBserver on Linux.
551 * The command "info catch" has been removed. It has been disabled
554 * The "catch exception" and "catch assert" commands now accept
555 a condition at the end of the command, much like the "break"
556 command does. For instance:
558 (gdb) catch exception Constraint_Error if Barrier = True
560 Previously, it was possible to add a condition to such catchpoints,
561 but it had to be done as a second step, after the catchpoint had been
562 created, using the "condition" command.
564 * The "info static-tracepoint-marker" command will now also work on
565 native Linux targets with in-process agent.
567 * GDB can now set breakpoints on inlined functions.
569 * The .gdb_index section has been updated to include symbols for
570 inlined functions. GDB will ignore older .gdb_index sections by
571 default, which could cause symbol files to be loaded more slowly
572 until their .gdb_index sections can be recreated. The new command
573 "set use-deprecated-index-sections on" will cause GDB to use any older
574 .gdb_index sections it finds. This will restore performance, but the
575 ability to set breakpoints on inlined functions will be lost in symbol
576 files with older .gdb_index sections.
578 The .gdb_index section has also been updated to record more information
579 about each symbol. This speeds up the "info variables", "info functions"
580 and "info types" commands when used with programs having the .gdb_index
581 section, as well as speeding up debugging with shared libraries using
582 the .gdb_index section.
584 * Ada support for GDB/MI Variable Objects has been added.
586 * GDB can now support 'breakpoint always-inserted mode' in 'record'
591 ** New command -info-os is the MI equivalent of "info os".
593 ** Output logs ("set logging" and related) now include MI output.
597 ** "set use-deprecated-index-sections on|off"
598 "show use-deprecated-index-sections on|off"
599 Controls the use of deprecated .gdb_index sections.
601 ** "catch load" and "catch unload" can be used to stop when a shared
602 library is loaded or unloaded, respectively.
604 ** "enable count" can be used to auto-disable a breakpoint after
607 ** "info vtbl" can be used to show the virtual method tables for
608 C++ and Java objects.
610 ** "explore" and its sub commands "explore value" and "explore type"
611 can be used to reccursively explore values and types of
612 expressions. These commands are available only if GDB is
613 configured with '--with-python'.
615 ** "info auto-load" shows status of all kinds of auto-loaded files,
616 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
617 sequences of commands files, "info auto-load python-scripts"
618 shows status of auto-loading Python script files,
619 "info auto-load local-gdbinit" shows status of loading init file
620 (.gdbinit) from current directory and "info auto-load libthread-db" shows
621 status of inferior specific thread debugging shared library loading.
623 ** "info auto-load-scripts", "set auto-load-scripts on|off"
624 and "show auto-load-scripts" commands have been deprecated, use their
625 "info auto-load python-scripts", "set auto-load python-scripts on|off"
626 and "show auto-load python-scripts" counterparts instead.
628 ** "dprintf location,format,args..." creates a dynamic printf, which
629 is basically a breakpoint that does a printf and immediately
630 resumes your program's execution, so it is like a printf that you
631 can insert dynamically at runtime instead of at compiletime.
633 ** "set print symbol"
635 Controls whether GDB attempts to display the symbol, if any,
636 corresponding to addresses it prints. This defaults to "on", but
637 you can set it to "off" to restore GDB's previous behavior.
639 * Deprecated commands
641 ** For the Renesas Super-H architecture, the "regs" command has been
642 deprecated, and "info all-registers" should be used instead.
646 Renesas RL78 rl78-*-elf
647 HP OpenVMS ia64 ia64-hp-openvms*
649 * GDBserver supports evaluation of breakpoint conditions. When
650 support is advertised by GDBserver, GDB may be told to send the
651 breakpoint conditions in bytecode form to GDBserver. GDBserver
652 will only report the breakpoint trigger to GDB when its condition
658 show mips compression
659 Select the compressed ISA encoding used in functions that have no symbol
660 information available. The encoding can be set to either of:
663 and is updated automatically from ELF file flags if available.
665 set breakpoint condition-evaluation
666 show breakpoint condition-evaluation
667 Control whether breakpoint conditions are evaluated by GDB ("host") or by
668 GDBserver ("target"). Default option "auto" chooses the most efficient
670 This option can improve debugger efficiency depending on the speed of the
674 Disable auto-loading globally.
677 Show auto-loading setting of all kinds of auto-loaded files.
679 set auto-load gdb-scripts on|off
680 show auto-load gdb-scripts
681 Control auto-loading of GDB canned sequences of commands files.
683 set auto-load python-scripts on|off
684 show auto-load python-scripts
685 Control auto-loading of Python script files.
687 set auto-load local-gdbinit on|off
688 show auto-load local-gdbinit
689 Control loading of init file (.gdbinit) from current directory.
691 set auto-load libthread-db on|off
692 show auto-load libthread-db
693 Control auto-loading of inferior specific thread debugging shared library.
695 set auto-load scripts-directory <dir1>[:<dir2>...]
696 show auto-load scripts-directory
697 Set a list of directories from which to load auto-loaded scripts.
698 Automatically loaded Python scripts and GDB scripts are located in one
699 of the directories listed by this option.
700 The delimiter (':' above) may differ according to the host platform.
702 set auto-load safe-path <dir1>[:<dir2>...]
703 show auto-load safe-path
704 Set a list of directories from which it is safe to auto-load files.
705 The delimiter (':' above) may differ according to the host platform.
707 set debug auto-load on|off
709 Control display of debugging info for auto-loading the files above.
711 set dprintf-style gdb|call|agent
713 Control the way in which a dynamic printf is performed; "gdb"
714 requests a GDB printf command, while "call" causes dprintf to call a
715 function in the inferior. "agent" requests that the target agent
716 (such as GDBserver) do the printing.
718 set dprintf-function <expr>
719 show dprintf-function
720 set dprintf-channel <expr>
722 Set the function and optional first argument to the call when using
723 the "call" style of dynamic printf.
725 set disconnected-dprintf on|off
726 show disconnected-dprintf
727 Control whether agent-style dynamic printfs continue to be in effect
728 after GDB disconnects.
730 * New configure options
733 Configure default value for the 'set auto-load scripts-directory'
734 setting above. It defaults to '$debugdir:$datadir/auto-load',
735 $debugdir representing global debugging info directories (available
736 via 'show debug-file-directory') and $datadir representing GDB's data
737 directory (available via 'show data-directory').
739 --with-auto-load-safe-path
740 Configure default value for the 'set auto-load safe-path' setting
741 above. It defaults to the --with-auto-load-dir setting.
743 --without-auto-load-safe-path
744 Set 'set auto-load safe-path' to '/', effectively disabling this
749 z0/z1 conditional breakpoints extension
751 The z0/z1 breakpoint insertion packets have been extended to carry
752 a list of conditional expressions over to the remote stub depending on the
753 condition evaluation mode. The use of this extension can be controlled
754 via the "set remote conditional-breakpoints-packet" command.
758 Specify the signals which the remote stub may pass to the debugged
759 program without GDB involvement.
761 * New command line options
763 --init-command=FILE, -ix Like --command, -x but execute it
764 before loading inferior.
765 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
766 execute it before loading inferior.
768 *** Changes in GDB 7.4
770 * GDB now handles ambiguous linespecs more consistently; the existing
771 FILE:LINE support has been expanded to other types of linespecs. A
772 breakpoint will now be set on all matching locations in all
773 inferiors, and locations will be added or removed according to
776 * GDB now allows you to skip uninteresting functions and files when
777 stepping with the "skip function" and "skip file" commands.
779 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
780 and "show remote hardware-watchpoint-length-limit". These allows to
781 set or show the maximum length limit (in bytes) of a remote
782 target hardware watchpoint.
784 This allows e.g. to use "unlimited" hardware watchpoints with the
785 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
786 watchpoints are slower than real hardware watchpoints but are
787 significantly faster than gdb software watchpoints.
791 ** The register_pretty_printer function in module gdb.printing now takes
792 an optional `replace' argument. If True, the new printer replaces any
795 ** The "maint set python print-stack on|off" command has been
796 deprecated and will be deleted in GDB 7.5.
797 A new command: "set python print-stack none|full|message" has
798 replaced it. Additionally, the default for "print-stack" is
799 now "message", which just prints the error message without
802 ** A prompt substitution hook (prompt_hook) is now available to the
805 ** A new Python module, gdb.prompt has been added to the GDB Python
806 modules library. This module provides functionality for
807 escape sequences in prompts (used by set/show
808 extended-prompt). These escape sequences are replaced by their
811 ** Python commands and convenience-functions located in
812 'data-directory'/python/gdb/command and
813 'data-directory'/python/gdb/function are now automatically loaded
816 ** Blocks now provide four new attributes. global_block and
817 static_block will return the global and static blocks
818 respectively. is_static and is_global are boolean attributes
819 that indicate if the block is one of those two types.
821 ** Symbols now provide the "type" attribute, the type of the symbol.
823 ** The "gdb.breakpoint" function has been deprecated in favor of
826 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
827 of a function. This class is based on the "finish" command
828 available in the CLI.
830 ** Type objects for struct and union types now allow access to
831 the fields using standard Python dictionary (mapping) methods.
832 For example, "some_type['myfield']" now works, as does
835 ** A new event "gdb.new_objfile" has been added, triggered by loading a
838 ** A new function, "deep_items" has been added to the gdb.types
839 module in the GDB Python modules library. This function returns
840 an iterator over the fields of a struct or union type. Unlike
841 the standard Python "iteritems" method, it will recursively traverse
842 any anonymous fields.
846 ** "*stopped" events can report several new "reason"s, such as
849 ** Breakpoint changes are now notified using new async records, like
850 "=breakpoint-modified".
852 ** New command -ada-task-info.
854 * libthread-db-search-path now supports two special values: $sdir and $pdir.
855 $sdir specifies the default system locations of shared libraries.
856 $pdir specifies the directory where the libpthread used by the application
859 GDB no longer looks in $sdir and $pdir after it has searched the directories
860 mentioned in libthread-db-search-path. If you want to search those
861 directories, they must be specified in libthread-db-search-path.
862 The default value of libthread-db-search-path on GNU/Linux and Solaris
863 systems is now "$sdir:$pdir".
865 $pdir is not supported by gdbserver, it is currently ignored.
866 $sdir is supported by gdbserver.
868 * New configure option --with-iconv-bin.
869 When using the internationalization support like the one in the GNU C
870 library, GDB will invoke the "iconv" program to get a list of supported
871 character sets. If this program lives in a non-standard location, one can
872 use this option to specify where to find it.
874 * When natively debugging programs on PowerPC BookE processors running
875 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
876 watchpoints, which specify a mask in addition to an address to watch.
877 The mask specifies that some bits of an address (the bits which are
878 reset in the mask) should be ignored when matching the address accessed
879 by the inferior against the watchpoint address. See the "PowerPC Embedded"
880 section in the user manual for more details.
882 * The new option --once causes GDBserver to stop listening for connections once
883 the first connection is made. The listening port used by GDBserver will
884 become available after that.
886 * New commands "info macros" and "alias" have been added.
888 * New function parameters suffix @entry specifies value of function parameter
889 at the time the function got called. Entry values are available only since
895 "!" is now an alias of the "shell" command.
896 Note that no space is needed between "!" and SHELL COMMAND.
900 watch EXPRESSION mask MASK_VALUE
901 The watch command now supports the mask argument which allows creation
902 of masked watchpoints, if the current architecture supports this feature.
904 info auto-load-scripts [REGEXP]
905 This command was formerly named "maintenance print section-scripts".
906 It is now generally useful and is no longer a maintenance-only command.
908 info macro [-all] [--] MACRO
909 The info macro command has new options `-all' and `--'. The first for
910 printing all definitions of a macro. The second for explicitly specifying
911 the end of arguments and the beginning of the macro name in case the macro
912 name starts with a hyphen.
914 collect[/s] EXPRESSIONS
915 The tracepoint collect command now takes an optional modifier "/s"
916 that directs it to dereference pointer-to-character types and
917 collect the bytes of memory up to a zero byte. The behavior is
918 similar to what you see when you use the regular print command on a
919 string. An optional integer following the "/s" sets a bound on the
920 number of bytes that will be collected.
923 The trace start command now interprets any supplied arguments as a
924 note to be recorded with the trace run, with an effect similar to
925 setting the variable trace-notes.
928 The trace stop command now interprets any arguments as a note to be
929 mentioned along with the tstatus report that the trace was stopped
930 with a command. The effect is similar to setting the variable
933 * Tracepoints can now be enabled and disabled at any time after a trace
934 experiment has been started using the standard "enable" and "disable"
935 commands. It is now possible to start a trace experiment with no enabled
936 tracepoints; GDB will display a warning, but will allow the experiment to
937 begin, assuming that tracepoints will be enabled as needed while the trace
940 * Fast tracepoints on 32-bit x86-architectures can now be placed at
941 locations with 4-byte instructions, when they were previously
942 limited to locations with instructions of 5 bytes or longer.
946 set debug dwarf2-read
947 show debug dwarf2-read
948 Turns on or off display of debugging messages related to reading
949 DWARF debug info. The default is off.
951 set debug symtab-create
952 show debug symtab-create
953 Turns on or off display of debugging messages related to symbol table
954 creation. The default is off.
958 Set the GDB prompt, and allow escape sequences to be inserted to
959 display miscellaneous information (see 'help set extended-prompt'
960 for the list of sequences). This prompt (and any information
961 accessed through the escape sequences) is updated every time the
964 set print entry-values (both|compact|default|if-needed|no|only|preferred)
965 show print entry-values
966 Set printing of frame argument values at function entry. In some cases
967 GDB can determine the value of function argument which was passed by the
968 function caller, even if the value was modified inside the called function.
970 set debug entry-values
971 show debug entry-values
972 Control display of debugging info for determining frame argument values at
973 function entry and virtual tail call frames.
975 set basenames-may-differ
976 show basenames-may-differ
977 Set whether a source file may have multiple base names.
978 (A "base name" is the name of a file with the directory part removed.
979 Example: The base name of "/home/user/hello.c" is "hello.c".)
980 If set, GDB will canonicalize file names (e.g., expand symlinks)
981 before comparing them. Canonicalization is an expensive operation,
982 but it allows the same file be known by more than one base name.
983 If not set (the default), all source files are assumed to have just
984 one base name, and gdb will do file name comparisons more efficiently.
990 Set a user name and notes for the current and any future trace runs.
991 This is useful for long-running and/or disconnected traces, to
992 inform others (or yourself) as to who is running the trace, supply
993 contact information, or otherwise explain what is going on.
996 show trace-stop-notes
997 Set a note attached to the trace run, that is displayed when the
998 trace has been stopped by a tstop command. This is useful for
999 instance as an explanation, if you are stopping a trace run that was
1000 started by someone else.
1002 * New remote packets
1006 Dynamically enable a tracepoint in a started trace experiment.
1010 Dynamically disable a tracepoint in a started trace experiment.
1014 Set the user and notes of the trace run.
1018 Query the current status of a tracepoint.
1022 Query the minimum length of instruction at which a fast tracepoint may
1025 * Dcache size (number of lines) and line-size are now runtime-configurable
1026 via "set dcache line" and "set dcache line-size" commands.
1030 Texas Instruments TMS320C6x tic6x-*-*
1034 Renesas RL78 rl78-*-elf
1036 *** Changes in GDB 7.3.1
1038 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1040 *** Changes in GDB 7.3
1042 * GDB has a new command: "thread find [REGEXP]".
1043 It finds the thread id whose name, target id, or thread extra info
1044 matches the given regular expression.
1046 * The "catch syscall" command now works on mips*-linux* targets.
1048 * The -data-disassemble MI command now supports modes 2 and 3 for
1049 dumping the instruction opcodes.
1051 * New command line options
1053 -data-directory DIR Specify DIR as the "data-directory".
1054 This is mostly for testing purposes.
1056 * The "maint set python auto-load on|off" command has been renamed to
1057 "set auto-load-scripts on|off".
1059 * GDB has a new command: "set directories".
1060 It is like the "dir" command except that it replaces the
1061 source path list instead of augmenting it.
1063 * GDB now understands thread names.
1065 On GNU/Linux, "info threads" will display the thread name as set by
1066 prctl or pthread_setname_np.
1068 There is also a new command, "thread name", which can be used to
1069 assign a name internally for GDB to display.
1072 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1073 has been integrated into GDB.
1077 ** The function gdb.Write now accepts an optional keyword 'stream'.
1078 This keyword, when provided, will direct the output to either
1079 stdout, stderr, or GDB's logging output.
1081 ** Parameters can now be be sub-classed in Python, and in particular
1082 you may implement the get_set_doc and get_show_doc functions.
1083 This improves how Parameter set/show documentation is processed
1084 and allows for more dynamic content.
1086 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1087 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1088 have an is_valid method.
1090 ** Breakpoints can now be sub-classed in Python, and in particular
1091 you may implement a 'stop' function that is executed each time
1092 the inferior reaches that breakpoint.
1094 ** New function gdb.lookup_global_symbol looks up a global symbol.
1096 ** GDB values in Python are now callable if the value represents a
1097 function. For example, if 'some_value' represents a function that
1098 takes two integer parameters and returns a value, you can call
1099 that function like so:
1101 result = some_value (10,20)
1103 ** Module gdb.types has been added.
1104 It contains a collection of utilities for working with gdb.Types objects:
1105 get_basic_type, has_field, make_enum_dict.
1107 ** Module gdb.printing has been added.
1108 It contains utilities for writing and registering pretty-printers.
1109 New classes: PrettyPrinter, SubPrettyPrinter,
1110 RegexpCollectionPrettyPrinter.
1111 New function: register_pretty_printer.
1113 ** New commands "info pretty-printers", "enable pretty-printer" and
1114 "disable pretty-printer" have been added.
1116 ** gdb.parameter("directories") is now available.
1118 ** New function gdb.newest_frame returns the newest frame in the
1121 ** The gdb.InferiorThread class has a new "name" attribute. This
1122 holds the thread's name.
1124 ** Python Support for Inferior events.
1125 Python scripts can add observers to be notified of events
1126 occurring in the process being debugged.
1127 The following events are currently supported:
1128 - gdb.events.cont Continue event.
1129 - gdb.events.exited Inferior exited event.
1130 - gdb.events.stop Signal received, and Breakpoint hit events.
1134 ** GDB now puts template parameters in scope when debugging in an
1135 instantiation. For example, if you have:
1137 template<int X> int func (void) { return X; }
1139 then if you step into func<5>, "print X" will show "5". This
1140 feature requires proper debuginfo support from the compiler; it
1141 was added to GCC 4.5.
1143 ** The motion commands "next", "finish", "until", and "advance" now
1144 work better when exceptions are thrown. In particular, GDB will
1145 no longer lose control of the inferior; instead, the GDB will
1146 stop the inferior at the point at which the exception is caught.
1147 This functionality requires a change in the exception handling
1148 code that was introduced in GCC 4.5.
1150 * GDB now follows GCC's rules on accessing volatile objects when
1151 reading or writing target state during expression evaluation.
1152 One notable difference to prior behavior is that "print x = 0"
1153 no longer generates a read of x; the value of the assignment is
1154 now always taken directly from the value being assigned.
1156 * GDB now has some support for using labels in the program's source in
1157 linespecs. For instance, you can use "advance label" to continue
1158 execution to a label.
1160 * GDB now has support for reading and writing a new .gdb_index
1161 section. This section holds a fast index of DWARF debugging
1162 information and can be used to greatly speed up GDB startup and
1163 operation. See the documentation for `save gdb-index' for details.
1165 * The "watch" command now accepts an optional "-location" argument.
1166 When used, this causes GDB to watch the memory referred to by the
1167 expression. Such a watchpoint is never deleted due to it going out
1170 * GDB now supports thread debugging of core dumps on GNU/Linux.
1172 GDB now activates thread debugging using the libthread_db library
1173 when debugging GNU/Linux core dumps, similarly to when debugging
1174 live processes. As a result, when debugging a core dump file, GDB
1175 is now able to display pthread_t ids of threads. For example, "info
1176 threads" shows the same output as when debugging the process when it
1177 was live. In earlier releases, you'd see something like this:
1180 * 1 LWP 6780 main () at main.c:10
1182 While now you see this:
1185 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1187 It is also now possible to inspect TLS variables when debugging core
1190 When debugging a core dump generated on a machine other than the one
1191 used to run GDB, you may need to point GDB at the correct
1192 libthread_db library with the "set libthread-db-search-path"
1193 command. See the user manual for more details on this command.
1195 * When natively debugging programs on PowerPC BookE processors running
1196 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1197 which stop execution of the inferior whenever it executes an instruction
1198 at any address within the specified range. See the "PowerPC Embedded"
1199 section in the user manual for more details.
1201 * New features in the GDB remote stub, GDBserver
1203 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1204 and i686 LynxOS (version 5.x).
1206 ** GDBserver is now supported on Blackfin Linux.
1208 * New native configurations
1210 ia64 HP-UX ia64-*-hpux*
1214 Analog Devices, Inc. Blackfin Processor bfin-*
1216 * Ada task switching is now supported on sparc-elf targets when
1217 debugging a program using the Ravenscar Profile. For more information,
1218 see the "Tasking Support when using the Ravenscar Profile" section
1219 in the GDB user manual.
1221 * Guile support was removed.
1223 * New features in the GNU simulator
1225 ** The --map-info flag lists all known core mappings.
1227 ** CFI flashes may be simulated via the "cfi" device.
1229 *** Changes in GDB 7.2
1231 * Shared library support for remote targets by default
1233 When GDB is configured for a generic, non-OS specific target, like
1234 for example, --target=arm-eabi or one of the many *-*-elf targets,
1235 GDB now queries remote stubs for loaded shared libraries using the
1236 `qXfer:libraries:read' packet. Previously, shared library support
1237 was always disabled for such configurations.
1241 ** Argument Dependent Lookup (ADL)
1243 In C++ ADL lookup directs function search to the namespaces of its
1244 arguments even if the namespace has not been imported.
1254 Here the compiler will search for `foo' in the namespace of 'b'
1255 and find A::foo. GDB now supports this. This construct is commonly
1256 used in the Standard Template Library for operators.
1258 ** Improved User Defined Operator Support
1260 In addition to member operators, GDB now supports lookup of operators
1261 defined in a namespace and imported with a `using' directive, operators
1262 defined in the global scope, operators imported implicitly from an
1263 anonymous namespace, and the ADL operators mentioned in the previous
1265 GDB now also supports proper overload resolution for all the previously
1266 mentioned flavors of operators.
1268 ** static const class members
1270 Printing of static const class members that are initialized in the
1271 class definition has been fixed.
1273 * Windows Thread Information Block access.
1275 On Windows targets, GDB now supports displaying the Windows Thread
1276 Information Block (TIB) structure. This structure is visible either
1277 by using the new command `info w32 thread-information-block' or, by
1278 dereferencing the new convenience variable named `$_tlb', a
1279 thread-specific pointer to the TIB. This feature is also supported
1280 when remote debugging using GDBserver.
1282 * Static tracepoints
1284 Static tracepoints are calls in the user program into a tracing
1285 library. One such library is a port of the LTTng kernel tracer to
1286 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1287 When debugging with GDBserver, GDB now supports combining the GDB
1288 tracepoint machinery with such libraries. For example: the user can
1289 use GDB to probe a static tracepoint marker (a call from the user
1290 program into the tracing library) with the new "strace" command (see
1291 "New commands" below). This creates a "static tracepoint" in the
1292 breakpoint list, that can be manipulated with the same feature set
1293 as fast and regular tracepoints. E.g., collect registers, local and
1294 global variables, collect trace state variables, and define
1295 tracepoint conditions. In addition, the user can collect extra
1296 static tracepoint marker specific data, by collecting the new
1297 $_sdata internal variable. When analyzing the trace buffer, you can
1298 inspect $_sdata like any other variable available to GDB. For more
1299 information, see the "Tracepoints" chapter in GDB user manual. New
1300 remote packets have been defined to support static tracepoints, see
1301 the "New remote packets" section below.
1303 * Better reconstruction of tracepoints after disconnected tracing
1305 GDB will attempt to download the original source form of tracepoint
1306 definitions when starting a trace run, and then will upload these
1307 upon reconnection to the target, resulting in a more accurate
1308 reconstruction of the tracepoints that are in use on the target.
1312 You can now exercise direct control over the ways that GDB can
1313 affect your program. For instance, you can disallow the setting of
1314 breakpoints, so that the program can run continuously (assuming
1315 non-stop mode). In addition, the "observer" variable is available
1316 to switch all of the different controls; in observer mode, GDB
1317 cannot affect the target's behavior at all, which is useful for
1318 tasks like diagnosing live systems in the field.
1320 * The new convenience variable $_thread holds the number of the
1323 * New remote packets
1327 Return the address of the Windows Thread Information Block of a given thread.
1331 In response to several of the tracepoint packets, the target may now
1332 also respond with a number of intermediate `qRelocInsn' request
1333 packets before the final result packet, to have GDB handle
1334 relocating an instruction to execute at a different address. This
1335 is particularly useful for stubs that support fast tracepoints. GDB
1336 reports support for this feature in the qSupported packet.
1340 List static tracepoint markers in the target program.
1344 List static tracepoint markers at a given address in the target
1347 qXfer:statictrace:read
1349 Read the static trace data collected (by a `collect $_sdata'
1350 tracepoint action). The remote stub reports support for this packet
1351 to gdb's qSupported query.
1355 Send the current settings of GDB's permission flags.
1359 Send part of the source (textual) form of a tracepoint definition,
1360 which includes location, conditional, and action list.
1362 * The source command now accepts a -s option to force searching for the
1363 script in the source search path even if the script name specifies
1366 * New features in the GDB remote stub, GDBserver
1368 - GDBserver now support tracepoints (including fast tracepoints, and
1369 static tracepoints). The feature is currently supported by the
1370 i386-linux and amd64-linux builds. See the "Tracepoints support
1371 in gdbserver" section in the manual for more information.
1373 GDBserver JIT compiles the tracepoint's conditional agent
1374 expression bytecode into native code whenever possible for low
1375 overhead dynamic tracepoints conditionals. For such tracepoints,
1376 an expression that examines program state is evaluated when the
1377 tracepoint is reached, in order to determine whether to capture
1378 trace data. If the condition is simple and false, processing the
1379 tracepoint finishes very quickly and no data is gathered.
1381 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1382 for static tracepoints support.
1384 - GDBserver now supports x86_64 Windows 64-bit debugging.
1386 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1387 it understands register description.
1389 * The --batch flag now disables pagination and queries.
1391 * X86 general purpose registers
1393 GDB now supports reading/writing byte, word and double-word x86
1394 general purpose registers directly. This means you can use, say,
1395 $ah or $ax to refer, respectively, to the byte register AH and
1396 16-bit word register AX that are actually portions of the 32-bit
1397 register EAX or 64-bit register RAX.
1399 * The `commands' command now accepts a range of breakpoints to modify.
1400 A plain `commands' following a command that creates multiple
1401 breakpoints affects all the breakpoints set by that command. This
1402 applies to breakpoints set by `rbreak', and also applies when a
1403 single `break' command creates multiple breakpoints (e.g.,
1404 breakpoints on overloaded c++ functions).
1406 * The `rbreak' command now accepts a filename specification as part of
1407 its argument, limiting the functions selected by the regex to those
1408 in the specified file.
1410 * Support for remote debugging Windows and SymbianOS shared libraries
1411 from Unix hosts has been improved. Non Windows GDB builds now can
1412 understand target reported file names that follow MS-DOS based file
1413 system semantics, such as file names that include drive letters and
1414 use the backslash character as directory separator. This makes it
1415 possible to transparently use the "set sysroot" and "set
1416 solib-search-path" on Unix hosts to point as host copies of the
1417 target's shared libraries. See the new command "set
1418 target-file-system-kind" described below, and the "Commands to
1419 specify files" section in the user manual for more information.
1423 eval template, expressions...
1424 Convert the values of one or more expressions under the control
1425 of the string template to a command line, and call it.
1427 set target-file-system-kind unix|dos-based|auto
1428 show target-file-system-kind
1429 Set or show the assumed file system kind for target reported file
1432 save breakpoints <filename>
1433 Save all current breakpoint definitions to a file suitable for use
1434 in a later debugging session. To read the saved breakpoint
1435 definitions, use the `source' command.
1437 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1440 info static-tracepoint-markers
1441 Display information about static tracepoint markers in the target.
1443 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1444 Define a static tracepoint by probing a marker at the given
1445 function, line, address, or marker ID.
1449 Enable and disable observer mode.
1451 set may-write-registers on|off
1452 set may-write-memory on|off
1453 set may-insert-breakpoints on|off
1454 set may-insert-tracepoints on|off
1455 set may-insert-fast-tracepoints on|off
1456 set may-interrupt on|off
1457 Set individual permissions for GDB effects on the target. Note that
1458 some of these settings can have undesirable or surprising
1459 consequences, particularly when changed in the middle of a session.
1460 For instance, disabling the writing of memory can prevent
1461 breakpoints from being inserted, cause single-stepping to fail, or
1462 even crash your program, if you disable after breakpoints have been
1463 inserted. However, GDB should not crash.
1465 set record memory-query on|off
1466 show record memory-query
1467 Control whether to stop the inferior if memory changes caused
1468 by an instruction cannot be recorded.
1473 The disassemble command now supports "start,+length" form of two arguments.
1477 ** GDB now provides a new directory location, called the python directory,
1478 where Python scripts written for GDB can be installed. The location
1479 of that directory is <data-directory>/python, where <data-directory>
1480 is the GDB data directory. For more details, see section `Scripting
1481 GDB using Python' in the manual.
1483 ** The GDB Python API now has access to breakpoints, symbols, symbol
1484 tables, program spaces, inferiors, threads and frame's code blocks.
1485 Additionally, GDB Parameters can now be created from the API, and
1486 manipulated via set/show in the CLI.
1488 ** New functions gdb.target_charset, gdb.target_wide_charset,
1489 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1491 ** New exception gdb.GdbError.
1493 ** Pretty-printers are now also looked up in the current program space.
1495 ** Pretty-printers can now be individually enabled and disabled.
1497 ** GDB now looks for names of Python scripts to auto-load in a
1498 special section named `.debug_gdb_scripts', in addition to looking
1499 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1501 * Tracepoint actions were unified with breakpoint commands. In particular,
1502 there are no longer differences in "info break" output for breakpoints and
1503 tracepoints and the "commands" command can be used for both tracepoints and
1504 regular breakpoints.
1508 ARM Symbian arm*-*-symbianelf*
1510 * D language support.
1511 GDB now supports debugging programs written in the D programming
1514 * GDB now supports the extended ptrace interface for PowerPC which is
1515 available since Linux kernel version 2.6.34. This automatically enables
1516 any hardware breakpoints and additional hardware watchpoints available in
1517 the processor. The old ptrace interface exposes just one hardware
1518 watchpoint and no hardware breakpoints.
1520 * GDB is now able to use the Data Value Compare (DVC) register available on
1521 embedded PowerPC processors to implement in hardware simple watchpoint
1522 conditions of the form:
1524 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1526 This works in native GDB running on Linux kernels with the extended ptrace
1527 interface mentioned above.
1529 *** Changes in GDB 7.1
1533 ** Namespace Support
1535 GDB now supports importing of namespaces in C++. This enables the
1536 user to inspect variables from imported namespaces. Support for
1537 namepace aliasing has also been added. So, if a namespace is
1538 aliased in the current scope (e.g. namepace C=A; ) the user can
1539 print variables using the alias (e.g. (gdb) print C::x).
1543 All known bugs relating to the printing of virtual base class were
1544 fixed. It is now possible to call overloaded static methods using a
1549 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1550 and reinterpret_cast<> are now handled by the C++ expression parser.
1554 Xilinx MicroBlaze microblaze-*-*
1559 Xilinx MicroBlaze microblaze
1562 * Multi-program debugging.
1564 GDB now has support for multi-program (a.k.a. multi-executable or
1565 multi-exec) debugging. This allows for debugging multiple inferiors
1566 simultaneously each running a different program under the same GDB
1567 session. See "Debugging Multiple Inferiors and Programs" in the
1568 manual for more information. This implied some user visible changes
1569 in the multi-inferior support. For example, "info inferiors" now
1570 lists inferiors that are not running yet or that have exited
1571 already. See also "New commands" and "New options" below.
1573 * New tracing features
1575 GDB's tracepoint facility now includes several new features:
1577 ** Trace state variables
1579 GDB tracepoints now include support for trace state variables, which
1580 are variables managed by the target agent during a tracing
1581 experiment. They are useful for tracepoints that trigger each
1582 other, so for instance one tracepoint can count hits in a variable,
1583 and then a second tracepoint has a condition that is true when the
1584 count reaches a particular value. Trace state variables share the
1585 $-syntax of GDB convenience variables, and can appear in both
1586 tracepoint actions and condition expressions. Use the "tvariable"
1587 command to create, and "info tvariables" to view; see "Trace State
1588 Variables" in the manual for more detail.
1592 GDB now includes an option for defining fast tracepoints, which
1593 targets may implement more efficiently, such as by installing a jump
1594 into the target agent rather than a trap instruction. The resulting
1595 speedup can be by two orders of magnitude or more, although the
1596 tradeoff is that some program locations on some target architectures
1597 might not allow fast tracepoint installation, for instance if the
1598 instruction to be replaced is shorter than the jump. To request a
1599 fast tracepoint, use the "ftrace" command, with syntax identical to
1600 the regular trace command.
1602 ** Disconnected tracing
1604 It is now possible to detach GDB from the target while it is running
1605 a trace experiment, then reconnect later to see how the experiment
1606 is going. In addition, a new variable disconnected-tracing lets you
1607 tell the target agent whether to continue running a trace if the
1608 connection is lost unexpectedly.
1612 GDB now has the ability to save the trace buffer into a file, and
1613 then use that file as a target, similarly to you can do with
1614 corefiles. You can select trace frames, print data that was
1615 collected in them, and use tstatus to display the state of the
1616 tracing run at the moment that it was saved. To create a trace
1617 file, use "tsave <filename>", and to use it, do "target tfile
1620 ** Circular trace buffer
1622 You can ask the target agent to handle the trace buffer as a
1623 circular buffer, discarding the oldest trace frames to make room for
1624 newer ones, by setting circular-trace-buffer to on. This feature may
1625 not be available for all target agents.
1630 The disassemble command, when invoked with two arguments, now requires
1631 the arguments to be comma-separated.
1634 The info variables command now displays variable definitions. Files
1635 which only declare a variable are not shown.
1638 The source command is now capable of sourcing Python scripts.
1639 This feature is dependent on the debugger being build with Python
1642 Related to this enhancement is also the introduction of a new command
1643 "set script-extension" (see below).
1645 * New commands (for set/show, see "New options" below)
1647 record save [<FILENAME>]
1648 Save a file (in core file format) containing the process record
1649 execution log for replay debugging at a later time.
1651 record restore <FILENAME>
1652 Restore the process record execution log that was saved at an
1653 earlier time, for replay debugging.
1655 add-inferior [-copies <N>] [-exec <FILENAME>]
1658 clone-inferior [-copies <N>] [ID]
1659 Make a new inferior ready to execute the same program another
1660 inferior has loaded.
1665 maint info program-spaces
1666 List the program spaces loaded into GDB.
1668 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1669 show remote interrupt-sequence
1670 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1671 as the sequence to the remote target in order to interrupt the execution.
1672 Ctrl-C is a default. Some system prefers BREAK which is high level of
1673 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1674 Magic SysRq g. It is BREAK signal and character 'g'.
1676 set remote interrupt-on-connect [on | off]
1677 show remote interrupt-on-connect
1678 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1679 remote target when gdb connects to it. This is needed when you debug
1682 set remotebreak [on | off]
1684 Deprecated. Use "set/show remote interrupt-sequence" instead.
1686 tvariable $NAME [ = EXP ]
1687 Create or modify a trace state variable.
1690 List trace state variables and their values.
1692 delete tvariable $NAME ...
1693 Delete one or more trace state variables.
1696 Evaluate the given expressions without collecting anything into the
1697 trace buffer. (Valid in tracepoint actions only.)
1699 ftrace FN / FILE:LINE / *ADDR
1700 Define a fast tracepoint at the given function, line, or address.
1702 * New expression syntax
1704 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1705 GDB now parses 0b101010 identically with 42.
1709 set follow-exec-mode new|same
1710 show follow-exec-mode
1711 Control whether GDB reuses the same inferior across an exec call or
1712 creates a new one. This is useful to be able to restart the old
1713 executable after the inferior having done an exec call.
1715 set default-collect EXPR, ...
1716 show default-collect
1717 Define a list of expressions to be collected at each tracepoint.
1718 This is a useful way to ensure essential items are not overlooked,
1719 such as registers or a critical global variable.
1721 set disconnected-tracing
1722 show disconnected-tracing
1723 If set to 1, the target is instructed to continue tracing if it
1724 loses its connection to GDB. If 0, the target is to stop tracing
1727 set circular-trace-buffer
1728 show circular-trace-buffer
1729 If set to on, the target is instructed to use a circular trace buffer
1730 and discard the oldest trace frames instead of stopping the trace due
1731 to a full trace buffer. If set to off, the trace stops when the buffer
1732 fills up. Some targets may not support this.
1734 set script-extension off|soft|strict
1735 show script-extension
1736 If set to "off", the debugger does not perform any script language
1737 recognition, and all sourced files are assumed to be GDB scripts.
1738 If set to "soft" (the default), files are sourced according to
1739 filename extension, falling back to GDB scripts if the first
1741 If set to "strict", files are sourced according to filename extension.
1743 set ada trust-PAD-over-XVS on|off
1744 show ada trust-PAD-over-XVS
1745 If off, activate a workaround against a bug in the debugging information
1746 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1747 the GCC sources for more information about the GNAT encoding and
1748 PAD types in particular). It is always safe to set this option to
1749 off, but this introduces a slight performance penalty. The default
1752 * Python API Improvements
1754 ** GDB provides the new class gdb.LazyString. This is useful in
1755 some pretty-printing cases. The new method gdb.Value.lazy_string
1756 provides a simple way to create objects of this type.
1758 ** The fields returned by gdb.Type.fields now have an
1759 `is_base_class' attribute.
1761 ** The new method gdb.Type.range returns the range of an array type.
1763 ** The new method gdb.parse_and_eval can be used to parse and
1764 evaluate an expression.
1766 * New remote packets
1769 Define a trace state variable.
1772 Get the current value of a trace state variable.
1775 Set desired tracing behavior upon disconnection.
1778 Set the trace buffer to be linear or circular.
1781 Get data about the tracepoints currently in use.
1785 Process record now works correctly with hardware watchpoints.
1787 Multiple bug fixes have been made to the mips-irix port, making it
1788 much more reliable. In particular:
1789 - Debugging threaded applications is now possible again. Previously,
1790 GDB would hang while starting the program, or while waiting for
1791 the program to stop at a breakpoint.
1792 - Attaching to a running process no longer hangs.
1793 - An error occurring while loading a core file has been fixed.
1794 - Changing the value of the PC register now works again. This fixes
1795 problems observed when using the "jump" command, or when calling
1796 a function from GDB, or even when assigning a new value to $pc.
1797 - With the "finish" and "return" commands, the return value for functions
1798 returning a small array is now correctly printed.
1799 - It is now possible to break on shared library code which gets executed
1800 during a shared library init phase (code executed while executing
1801 their .init section). Previously, the breakpoint would have no effect.
1802 - GDB is now able to backtrace through the signal handler for
1803 non-threaded programs.
1805 PIE (Position Independent Executable) programs debugging is now supported.
1806 This includes debugging execution of PIC (Position Independent Code) shared
1807 libraries although for that, it should be possible to run such libraries as an
1810 *** Changes in GDB 7.0
1812 * GDB now has an interface for JIT compilation. Applications that
1813 dynamically generate code can create symbol files in memory and register
1814 them with GDB. For users, the feature should work transparently, and
1815 for JIT developers, the interface is documented in the GDB manual in the
1816 "JIT Compilation Interface" chapter.
1818 * Tracepoints may now be conditional. The syntax is as for
1819 breakpoints; either an "if" clause appended to the "trace" command,
1820 or the "condition" command is available. GDB sends the condition to
1821 the target for evaluation using the same bytecode format as is used
1822 for tracepoint actions.
1824 * The disassemble command now supports: an optional /r modifier, print the
1825 raw instructions in hex as well as in symbolic form, and an optional /m
1826 modifier to print mixed source+assembly.
1828 * Process record and replay
1830 In a architecture environment that supports ``process record and
1831 replay'', ``process record and replay'' target can record a log of
1832 the process execution, and replay it with both forward and reverse
1835 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1836 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1837 set execution-direction {forward|reverse}, for targets that support
1840 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1841 feature is available with a native GDB running on kernel version
1844 * GDB now has support for multi-byte and wide character sets on the
1845 target. Strings whose character type is wchar_t, char16_t, or
1846 char32_t are now correctly printed. GDB supports wide- and unicode-
1847 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1848 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1849 `printf'. This feature requires iconv to work properly; if your
1850 system does not have a working iconv, GDB can use GNU libiconv. See
1851 the installation instructions for more information.
1853 * GDB now supports automatic retrieval of shared library files from
1854 remote targets. To use this feature, specify a system root that begins
1855 with the `remote:' prefix, either via the `set sysroot' command or via
1856 the `--with-sysroot' configure-time option.
1858 * "info sharedlibrary" now takes an optional regex of libraries to show,
1859 and it now reports if a shared library has no debugging information.
1861 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1862 now complete on file names.
1864 * When completing in expressions, gdb will attempt to limit
1865 completions to allowable structure or union fields, where appropriate.
1866 For instance, consider:
1868 # struct example { int f1; double f2; };
1869 # struct example variable;
1872 If the user types TAB at the end of this command line, the available
1873 completions will be "f1" and "f2".
1875 * Inlined functions are now supported. They show up in backtraces, and
1876 the "step", "next", and "finish" commands handle them automatically.
1878 * GDB now supports the token-splicing (##) and stringification (#)
1879 operators when expanding macros. It also supports variable-arity
1882 * GDB now supports inspecting extra signal information, exported by
1883 the new $_siginfo convenience variable. The feature is currently
1884 implemented on linux ARM, i386 and amd64.
1886 * GDB can now display the VFP floating point registers and NEON vector
1887 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1888 can provide these registers (requires Linux 2.6.30 or later). Remote
1889 and simulator targets may also provide them.
1891 * New remote packets
1894 Search memory for a sequence of bytes.
1897 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1898 operation over reliable transport links. Use of this packet is
1899 controlled by the `set remote noack-packet' command.
1902 Kill the process with the specified process ID. Use this in preference
1903 to `k' when multiprocess protocol extensions are supported.
1906 Obtains additional operating system information
1910 Read or write additional signal information.
1912 * Removed remote protocol undocumented extension
1914 An undocumented extension to the remote protocol's `S' stop reply
1915 packet that permited the stub to pass a process id was removed.
1916 Remote servers should use the `T' stop reply packet instead.
1918 * GDB now supports multiple function calling conventions according to the
1919 DWARF-2 DW_AT_calling_convention function attribute.
1921 * The SH target utilizes the aforementioned change to distinguish between gcc
1922 and Renesas calling convention. It also adds the new CLI commands
1923 `set/show sh calling-convention'.
1925 * GDB can now read compressed debug sections, as produced by GNU gold
1926 with the --compress-debug-sections=zlib flag.
1928 * 64-bit core files are now supported on AIX.
1930 * Thread switching is now supported on Tru64.
1932 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1933 which will be allocated using malloc later in program execution.
1935 * The qXfer:libraries:read remote procotol packet now allows passing a
1936 list of section offsets.
1938 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1939 conditions handling signals delivered during attach or thread creation
1940 have also been fixed.
1942 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1943 From the user's standpoint, all unqualified instances of True and False
1944 are treated as the standard definitions, regardless of context.
1946 * GDB now parses C++ symbol and type names more flexibly. For
1949 template<typename T> class C { };
1952 GDB will now correctly handle all of:
1954 ptype C<char const *>
1955 ptype C<char const*>
1956 ptype C<const char *>
1957 ptype C<const char*>
1959 * New features in the GDB remote stub, gdbserver
1961 - The "--wrapper" command-line argument tells gdbserver to use a
1962 wrapper program to launch programs for debugging.
1964 - On PowerPC and S/390 targets, it is now possible to use a single
1965 gdbserver executable to debug both 32-bit and 64-bit programs.
1966 (This requires gdbserver itself to be built as a 64-bit executable.)
1968 - gdbserver uses the new noack protocol mode for TCP connections to
1969 reduce communications latency, if also supported and enabled in GDB.
1971 - Support for the sparc64-linux-gnu target is now included in
1974 - The amd64-linux build of gdbserver now supports debugging both
1975 32-bit and 64-bit programs.
1977 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1978 now support hardware watchpoints, and will use them automatically
1983 GDB now has support for scripting using Python. Whether this is
1984 available is determined at configure time.
1986 New GDB commands can now be written in Python.
1988 * Ada tasking support
1990 Ada tasks can now be inspected in GDB. The following commands have
1994 Print the list of Ada tasks.
1996 Print detailed information about task number N.
1998 Print the task number of the current task.
2000 Switch the context of debugging to task number N.
2002 * Support for user-defined prefixed commands. The "define" command can
2003 add new commands to existing prefixes, e.g. "target".
2005 * Multi-inferior, multi-process debugging.
2007 GDB now has generalized support for multi-inferior debugging. See
2008 "Debugging Multiple Inferiors" in the manual for more information.
2009 Although availability still depends on target support, the command
2010 set is more uniform now. The GNU/Linux specific multi-forks support
2011 has been migrated to this new framework. This implied some user
2012 visible changes; see "New commands" and also "Removed commands"
2015 * Target descriptions can now describe the target OS ABI. See the
2016 "Target Description Format" section in the user manual for more
2019 * Target descriptions can now describe "compatible" architectures
2020 to indicate that the target can execute applications for a different
2021 architecture in addition to those for the main target architecture.
2022 See the "Target Description Format" section in the user manual for
2025 * Multi-architecture debugging.
2027 GDB now includes general supports for debugging applications on
2028 hybrid systems that use more than one single processor architecture
2029 at the same time. Each such hybrid architecture still requires
2030 specific support to be added. The only hybrid architecture supported
2031 in this version of GDB is the Cell Broadband Engine.
2033 * GDB now supports integrated debugging of Cell/B.E. applications that
2034 use both the PPU and SPU architectures. To enable support for hybrid
2035 Cell/B.E. debugging, you need to configure GDB to support both the
2036 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2037 --enable-targets configure option.
2039 * Non-stop mode debugging.
2041 For some targets, GDB now supports an optional mode of operation in
2042 which you can examine stopped threads while other threads continue
2043 to execute freely. This is referred to as non-stop mode, with the
2044 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2045 section in the user manual for more information.
2047 To be able to support remote non-stop debugging, a remote stub needs
2048 to implement the non-stop mode remote protocol extensions, as
2049 described in the "Remote Non-Stop" section of the user manual. The
2050 GDB remote stub, gdbserver, has been adjusted to support these
2051 extensions on linux targets.
2053 * New commands (for set/show, see "New options" below)
2055 catch syscall [NAME(S) | NUMBER(S)]
2056 Catch system calls. Arguments, which should be names of system
2057 calls or their numbers, mean catch only those syscalls. Without
2058 arguments, every syscall will be caught. When the inferior issues
2059 any of the specified syscalls, GDB will stop and announce the system
2060 call, both when it is called and when its call returns. This
2061 feature is currently available with a native GDB running on the
2062 Linux Kernel, under the following architectures: x86, x86_64,
2063 PowerPC and PowerPC64.
2065 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2067 Search memory for a sequence of bytes.
2069 maint set python print-stack
2070 maint show python print-stack
2071 Show a stack trace when an error is encountered in a Python script.
2074 Invoke CODE by passing it to the Python interpreter.
2079 These allow macros to be defined, undefined, and listed
2083 Show operating system information about processes.
2086 List the inferiors currently under GDB's control.
2089 Switch focus to inferior number NUM.
2092 Detach from inferior number NUM.
2095 Kill inferior number NUM.
2099 set spu stop-on-load
2100 show spu stop-on-load
2101 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2103 set spu auto-flush-cache
2104 show spu auto-flush-cache
2105 Control whether to automatically flush the software-managed cache
2106 during Cell/B.E. debugging.
2108 set sh calling-convention
2109 show sh calling-convention
2110 Control the calling convention used when calling SH target functions.
2113 show debug timestamp
2114 Control display of timestamps with GDB debugging output.
2116 set disassemble-next-line
2117 show disassemble-next-line
2118 Control display of disassembled source lines or instructions when
2121 set remote noack-packet
2122 show remote noack-packet
2123 Set/show the use of remote protocol QStartNoAckMode packet. See above
2124 under "New remote packets."
2126 set remote query-attached-packet
2127 show remote query-attached-packet
2128 Control use of remote protocol `qAttached' (query-attached) packet.
2130 set remote read-siginfo-object
2131 show remote read-siginfo-object
2132 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2135 set remote write-siginfo-object
2136 show remote write-siginfo-object
2137 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2140 set remote reverse-continue
2141 show remote reverse-continue
2142 Control use of remote protocol 'bc' (reverse-continue) packet.
2144 set remote reverse-step
2145 show remote reverse-step
2146 Control use of remote protocol 'bs' (reverse-step) packet.
2148 set displaced-stepping
2149 show displaced-stepping
2150 Control displaced stepping mode. Displaced stepping is a way to
2151 single-step over breakpoints without removing them from the debuggee.
2152 Also known as "out-of-line single-stepping".
2155 show debug displaced
2156 Control display of debugging info for displaced stepping.
2158 maint set internal-error
2159 maint show internal-error
2160 Control what GDB does when an internal error is detected.
2162 maint set internal-warning
2163 maint show internal-warning
2164 Control what GDB does when an internal warning is detected.
2169 Use a wrapper program to launch programs for debugging.
2171 set multiple-symbols (all|ask|cancel)
2172 show multiple-symbols
2173 The value of this variable can be changed to adjust the debugger behavior
2174 when an expression or a breakpoint location contains an ambiguous symbol
2175 name (an overloaded function name, for instance).
2177 set breakpoint always-inserted
2178 show breakpoint always-inserted
2179 Keep breakpoints always inserted in the target, as opposed to inserting
2180 them when resuming the target, and removing them when the target stops.
2181 This option can improve debugger performance on slow remote targets.
2183 set arm fallback-mode (arm|thumb|auto)
2184 show arm fallback-mode
2185 set arm force-mode (arm|thumb|auto)
2187 These commands control how ARM GDB determines whether instructions
2188 are ARM or Thumb. The default for both settings is auto, which uses
2189 the current CPSR value for instructions without symbols; previous
2190 versions of GDB behaved as if "set arm fallback-mode arm".
2192 set disable-randomization
2193 show disable-randomization
2194 Standalone programs run with the virtual address space randomization enabled
2195 by default on some platforms. This option keeps the addresses stable across
2196 multiple debugging sessions.
2200 Control whether other threads are stopped or not when some thread hits
2205 Requests that asynchronous execution is enabled in the target, if available.
2206 In this case, it's possible to resume target in the background, and interact
2207 with GDB while the target is running. "show target-async" displays the
2208 current state of asynchronous execution of the target.
2210 set target-wide-charset
2211 show target-wide-charset
2212 The target-wide-charset is the name of the character set that GDB
2213 uses when printing characters whose type is wchar_t.
2215 set tcp auto-retry (on|off)
2217 set tcp connect-timeout
2218 show tcp connect-timeout
2219 These commands allow GDB to retry failed TCP connections to a remote stub
2220 with a specified timeout period; this is useful if the stub is launched
2221 in parallel with GDB but may not be ready to accept connections immediately.
2223 set libthread-db-search-path
2224 show libthread-db-search-path
2225 Control list of directories which GDB will search for appropriate
2228 set schedule-multiple (on|off)
2229 show schedule-multiple
2230 Allow GDB to resume all threads of all processes or only threads of
2231 the current process.
2235 Use more aggressive caching for accesses to the stack. This improves
2236 performance of remote debugging (particularly backtraces) without
2237 affecting correctness.
2239 set interactive-mode (on|off|auto)
2240 show interactive-mode
2241 Control whether GDB runs in interactive mode (on) or not (off).
2242 When in interactive mode, GDB waits for the user to answer all
2243 queries. Otherwise, GDB does not wait and assumes the default
2244 answer. When set to auto (the default), GDB determines which
2245 mode to use based on the stdin settings.
2250 For program forks, this is replaced by the new more generic `info
2251 inferiors' command. To list checkpoints, you can still use the
2252 `info checkpoints' command, which was an alias for the `info forks'
2256 Replaced by the new `inferior' command. To switch between
2257 checkpoints, you can still use the `restart' command, which was an
2258 alias for the `fork' command.
2261 This is removed, since some targets don't have a notion of
2262 processes. To switch between processes, you can still use the
2263 `inferior' command using GDB's own inferior number.
2266 For program forks, this is replaced by the new more generic `kill
2267 inferior' command. To delete a checkpoint, you can still use the
2268 `delete checkpoint' command, which was an alias for the `delete
2272 For program forks, this is replaced by the new more generic `detach
2273 inferior' command. To detach a checkpoint, you can still use the
2274 `detach checkpoint' command, which was an alias for the `detach
2277 * New native configurations
2279 x86/x86_64 Darwin i[34567]86-*-darwin*
2281 x86_64 MinGW x86_64-*-mingw*
2285 Lattice Mico32 lm32-*
2286 x86 DICOS i[34567]86-*-dicos*
2287 x86_64 DICOS x86_64-*-dicos*
2290 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2291 (mingw32ce) debugging.
2297 These commands were actually not implemented on any target.
2299 *** Changes in GDB 6.8
2301 * New native configurations
2303 NetBSD/hppa hppa*-*netbsd*
2304 Xtensa GNU/Linux xtensa*-*-linux*
2308 NetBSD/hppa hppa*-*-netbsd*
2309 Xtensa GNU/Lunux xtensa*-*-linux*
2311 * Change in command line behavior -- corefiles vs. process ids.
2313 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2314 attaching to process NUMBER fails, GDB no longer attempts to open a
2315 core file named NUMBER. Attaching to a program using the -c option
2316 is no longer supported. Instead, use the '-p' or '--pid' options.
2318 * GDB can now be built as a native debugger for debugging Windows x86
2319 (mingw32) Portable Executable (PE) programs.
2321 * Pending breakpoints no longer change their number when their address
2324 * GDB now supports breakpoints with multiple locations,
2325 including breakpoints on C++ constructors, inside C++ templates,
2326 and in inlined functions.
2328 * GDB's ability to debug optimized code has been improved. GDB more
2329 accurately identifies function bodies and lexical blocks that occupy
2330 more than one contiguous range of addresses.
2332 * Target descriptions can now describe registers for PowerPC.
2334 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2335 registers on PowerPC targets.
2337 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2338 targets even when the libthread_db library is not available.
2340 * The GDB remote stub, gdbserver, now supports the new file transfer
2341 commands (remote put, remote get, and remote delete).
2343 * The GDB remote stub, gdbserver, now supports run and attach in
2344 extended-remote mode.
2346 * hppa*64*-*-hpux11* target broken
2347 The debugger is unable to start a program and fails with the following
2348 error: "Error trying to get information about dynamic linker".
2349 The gdb-6.7 release is also affected.
2351 * GDB now supports the --enable-targets= configure option to allow
2352 building a single GDB executable that supports multiple remote
2353 target architectures.
2355 * GDB now supports debugging C and C++ programs which use the
2356 Decimal Floating Point extension. In addition, the PowerPC target
2357 now has a set of pseudo-registers to inspect decimal float values
2358 stored in two consecutive float registers.
2360 * The -break-insert MI command can optionally create pending
2363 * Improved support for debugging Ada
2364 Many improvements to the Ada language support have been made. These
2366 - Better support for Ada2005 interface types
2367 - Improved handling of arrays and slices in general
2368 - Better support for Taft-amendment types
2369 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2371 - Improved command completion in Ada
2374 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2379 set print frame-arguments (all|scalars|none)
2380 show print frame-arguments
2381 The value of this variable can be changed to control which argument
2382 values should be printed by the debugger when displaying a frame.
2387 Transfer files to and from a remote target, and delete remote files.
2394 Transfer files to and from a remote target, and delete remote files.
2396 * New remote packets
2403 Open, close, read, write, and delete files on the remote system.
2406 Attach to an existing process on the remote system, in extended-remote
2410 Run a new process on the remote system, in extended-remote mode.
2412 *** Changes in GDB 6.7
2414 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2415 bfd, libiberty and opcodes, as revealed by static analysis donated by
2416 Coverity, Inc. (http://scan.coverity.com).
2418 * When looking up multiply-defined global symbols, GDB will now prefer the
2419 symbol definition in the current shared library if it was built using the
2420 -Bsymbolic linker option.
2422 * When the Text User Interface (TUI) is not configured, GDB will now
2423 recognize the -tui command-line option and print a message that the TUI
2426 * The GDB remote stub, gdbserver, now has lower overhead for high
2427 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2429 * GDB for MIPS targets now autodetects whether a remote target provides
2430 32-bit or 64-bit register values.
2432 * Support for C++ member pointers has been improved.
2434 * GDB now understands XML target descriptions, which specify the
2435 target's overall architecture. GDB can read a description from
2436 a local file or over the remote serial protocol.
2438 * Vectors of single-byte data use a new integer type which is not
2439 automatically displayed as character or string data.
2441 * The /s format now works with the print command. It displays
2442 arrays of single-byte integers and pointers to single-byte integers
2445 * Target descriptions can now describe target-specific registers,
2446 for architectures which have implemented the support (currently
2447 only ARM, M68K, and MIPS).
2449 * GDB and the GDB remote stub, gdbserver, now support the XScale
2452 * The GDB remote stub, gdbserver, has been updated to support
2453 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2454 has been rewritten to use the standard GDB remote protocol.
2456 * GDB can now step into C++ functions which are called through thunks.
2458 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2460 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2461 layout. It also supports a TextSeg= and DataSeg= response when only
2462 segment base addresses (rather than offsets) are available.
2464 * The /i format now outputs any trailing branch delay slot instructions
2465 immediately following the last instruction within the count specified.
2467 * The GDB remote protocol "T" stop reply packet now supports a
2468 "library" response. Combined with the new "qXfer:libraries:read"
2469 packet, this response allows GDB to debug shared libraries on targets
2470 where the operating system manages the list of loaded libraries (e.g.
2471 Windows and SymbianOS).
2473 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2474 (DLLs) on Windows and Windows CE targets.
2476 * GDB now supports a faster verification that a .debug file matches its binary
2477 according to its build-id signature, if the signature is present.
2483 Enable or disable hardware flow control (RTS/CTS) on the serial port
2484 when debugging using remote targets.
2486 set mem inaccessible-by-default
2487 show mem inaccessible-by-default
2488 If the target supplies a memory map, for instance via the remote
2489 protocol's "qXfer:memory-map:read" packet, setting this variable
2490 prevents GDB from accessing memory outside the memory map. This
2491 is useful for targets with memory mapped registers or which react
2492 badly to accesses of unmapped address space.
2494 set breakpoint auto-hw
2495 show breakpoint auto-hw
2496 If the target supplies a memory map, for instance via the remote
2497 protocol's "qXfer:memory-map:read" packet, setting this variable
2498 lets GDB use hardware breakpoints automatically for memory regions
2499 where it can not use software breakpoints. This covers both the
2500 "break" command and internal breakpoints used for other commands
2501 including "next" and "finish".
2504 catch exception unhandled
2505 Stop the program execution when Ada exceptions are raised.
2508 Stop the program execution when an Ada assertion failed.
2512 Set an alternate system root for target files. This is a more
2513 general version of "set solib-absolute-prefix", which is now
2514 an alias to "set sysroot".
2517 Provide extended SPU facility status information. This set of
2518 commands is available only when debugging the Cell/B.E. SPU
2521 * New native configurations
2523 OpenBSD/sh sh*-*openbsd*
2526 unset tdesc filename
2528 Use the specified local file as an XML target description, and do
2529 not query the target for its built-in description.
2533 OpenBSD/sh sh*-*-openbsd*
2534 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2535 Toshiba Media Processor mep-elf
2537 * New remote packets
2540 Ignore the specified signals; pass them directly to the debugged program
2541 without stopping other threads or reporting them to GDB.
2543 qXfer:features:read:
2544 Read an XML target description from the target, which describes its
2549 Read or write contents of an spufs file on the target system. These
2550 packets are available only on the Cell/B.E. SPU architecture.
2552 qXfer:libraries:read:
2553 Report the loaded shared libraries. Combined with new "T" packet
2554 response, this packet allows GDB to debug shared libraries on
2555 targets where the operating system manages the list of loaded
2556 libraries (e.g. Windows and SymbianOS).
2560 Support for these obsolete configurations has been removed.
2568 i[34567]86-*-lynxos*
2569 i[34567]86-*-netware*
2570 i[34567]86-*-sco3.2v5*
2571 i[34567]86-*-sco3.2v4*
2573 i[34567]86-*-sysv4.2*
2576 i[34567]86-*-unixware2*
2577 i[34567]86-*-unixware*
2586 * Other removed features
2593 Various m68k-only ROM monitors.
2600 Various Renesas ROM monitors and debugging interfaces for SH and
2605 Support for a Macraigor serial interface to on-chip debugging.
2606 GDB does not directly support the newer parallel or USB
2611 A debug information format. The predecessor to DWARF 2 and
2612 DWARF 3, which are still supported.
2614 Support for the HP aCC compiler on HP-UX/PA-RISC
2616 SOM-encapsulated symbolic debugging information, automatic
2617 invocation of pxdb, and the aCC custom C++ ABI. This does not
2618 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2619 with aCC can still be debugged on an assembly level.
2621 MIPS ".pdr" sections
2623 A MIPS-specific format used to describe stack frame layout
2624 in debugging information.
2628 GDB could work with an older version of Guile to debug
2629 the interpreter and Scheme programs running in it.
2631 set mips stack-arg-size
2632 set mips saved-gpreg-size
2634 Use "set mips abi" to control parameter passing for MIPS.
2636 *** Changes in GDB 6.6
2641 Cell Broadband Engine SPU spu-elf
2643 * GDB can now be configured as a cross-debugger targeting native Windows
2644 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2645 running on a Windows system over TCP/IP to debug Windows programs.
2647 * The GDB remote stub, gdbserver, has been updated to support Windows and
2648 Cygwin debugging. Both single-threaded and multi-threaded programs are
2651 * The "set trust-readonly-sections" command works again. This command was
2652 broken in GDB 6.3, 6.4, and 6.5.
2654 * The "load" command now supports writing to flash memory, if the remote
2655 stub provides the required support.
2657 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2658 longer requires symbolic debug information (e.g. DWARF-2).
2663 unset substitute-path
2664 show substitute-path
2665 Manage a list of substitution rules that GDB uses to rewrite the name
2666 of the directories where the sources are located. This can be useful
2667 for instance when the sources were moved to a different location
2668 between compilation and debugging.
2672 Print each CLI command as it is executed. Each command is prefixed with
2673 a number of `+' symbols representing the nesting depth.
2674 The source command now has a `-v' option to enable the same feature.
2678 The ARM Demon monitor support (RDP protocol, "target rdp").
2680 Kernel Object Display, an embedded debugging feature which only worked with
2681 an obsolete version of Cisco IOS.
2683 The 'set download-write-size' and 'show download-write-size' commands.
2685 * New remote packets
2688 Tell a stub about GDB client features, and request remote target features.
2689 The first feature implemented is PacketSize, which allows the target to
2690 specify the size of packets it can handle - to minimize the number of
2691 packets required and improve performance when connected to a remote
2695 Fetch an OS auxilliary vector from the remote stub. This packet is a
2696 more efficient replacement for qPart:auxv:read.
2698 qXfer:memory-map:read:
2699 Fetch a memory map from the remote stub, including information about
2700 RAM, ROM, and flash memory devices.
2705 Erase and program a flash memory device.
2707 * Removed remote packets
2710 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2711 used it, and only gdbserver implemented it.
2713 *** Changes in GDB 6.5
2717 Renesas M32C/M16C m32c-elf
2719 Morpho Technologies ms1 ms1-elf
2723 init-if-undefined Initialize a convenience variable, but
2724 only if it doesn't already have a value.
2726 The following commands are presently only implemented for native GNU/Linux:
2728 checkpoint Save a snapshot of the program state.
2730 restart <n> Return the program state to a
2731 previously saved state.
2733 info checkpoints List currently saved checkpoints.
2735 delete-checkpoint <n> Delete a previously saved checkpoint.
2737 set|show detach-on-fork Tell gdb whether to detach from a newly
2738 forked process, or to keep debugging it.
2740 info forks List forks of the user program that
2741 are available to be debugged.
2743 fork <n> Switch to debugging one of several
2744 forks of the user program that are
2745 available to be debugged.
2747 delete-fork <n> Delete a fork from the list of forks
2748 that are available to be debugged (and
2749 kill the forked process).
2751 detach-fork <n> Delete a fork from the list of forks
2752 that are available to be debugged (and
2753 allow the process to continue).
2757 Morpho Technologies ms2 ms1-elf
2759 * Improved Windows host support
2761 GDB now builds as a cross debugger hosted on i686-mingw32, including
2762 native console support, and remote communications using either
2763 network sockets or serial ports.
2765 * Improved Modula-2 language support
2767 GDB can now print most types in the Modula-2 syntax. This includes:
2768 basic types, set types, record types, enumerated types, range types,
2769 pointer types and ARRAY types. Procedure var parameters are correctly
2770 printed and hexadecimal addresses and character constants are also
2771 written in the Modula-2 syntax. Best results can be obtained by using
2772 GNU Modula-2 together with the -gdwarf-2 command line option.
2776 The ARM rdi-share module.
2778 The Netware NLM debug server.
2780 *** Changes in GDB 6.4
2782 * New native configurations
2784 OpenBSD/arm arm*-*-openbsd*
2785 OpenBSD/mips64 mips64-*-openbsd*
2789 Morpho Technologies ms1 ms1-elf
2791 * New command line options
2793 --batch-silent As for --batch, but totally silent.
2794 --return-child-result The debugger will exist with the same value
2795 the child (debugged) program exited with.
2796 --eval-command COMMAND, -ex COMMAND
2797 Execute a single GDB CLI command. This may be
2798 specified multiple times and in conjunction
2799 with the --command (-x) option.
2801 * Deprecated commands removed
2803 The following commands, that were deprecated in 2000, have been
2807 set|show arm disassembly-flavor set|show arm disassembler
2808 othernames set arm disassembler
2809 set|show remotedebug set|show debug remote
2810 set|show archdebug set|show debug arch
2811 set|show eventdebug set|show debug event
2814 * New BSD user-level threads support
2816 It is now possible to debug programs using the user-level threads
2817 library on OpenBSD and FreeBSD. Currently supported (target)
2820 FreeBSD/amd64 x86_64-*-freebsd*
2821 FreeBSD/i386 i386-*-freebsd*
2822 OpenBSD/i386 i386-*-openbsd*
2824 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2825 are not yet supported.
2827 * New support for Matsushita MN10300 w/sim added
2828 (Work in progress). mn10300-elf.
2830 * REMOVED configurations and files
2832 VxWorks and the XDR protocol *-*-vxworks
2833 Motorola MCORE mcore-*-*
2834 National Semiconductor NS32000 ns32k-*-*
2836 * New "set print array-indexes" command
2838 After turning this setting "on", GDB prints the index of each element
2839 when displaying arrays. The default is "off" to preserve the previous
2842 * VAX floating point support
2844 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2846 * User-defined command support
2848 In addition to using $arg0..$arg9 for argument passing, it is now possible
2849 to use $argc to determine now many arguments have been passed. See the
2850 section on user-defined commands in the user manual for more information.
2852 *** Changes in GDB 6.3:
2854 * New command line option
2856 GDB now accepts -l followed by a number to set the timeout for remote
2859 * GDB works with GCC -feliminate-dwarf2-dups
2861 GDB now supports a more compact representation of DWARF-2 debug
2862 information using DW_FORM_ref_addr references. These are produced
2863 by GCC with the option -feliminate-dwarf2-dups and also by some
2864 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2865 to use -feliminate-dwarf2-dups.
2867 * Internationalization
2869 When supported by the host system, GDB will be built with
2870 internationalization (libintl). The task of marking up the sources is
2871 continued, we're looking forward to our first translation.
2875 Initial support for debugging programs compiled with the GNAT
2876 implementation of the Ada programming language has been integrated
2877 into GDB. In this release, support is limited to expression evaluation.
2879 * New native configurations
2881 GNU/Linux/m32r m32r-*-linux-gnu
2885 GDB's remote protocol now includes support for the 'p' packet. This
2886 packet is used to fetch individual registers from a remote inferior.
2888 * END-OF-LIFE registers[] compatibility module
2890 GDB's internal register infrastructure has been completely rewritten.
2891 The new infrastructure making possible the implementation of key new
2892 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2895 GDB 6.3 will be the last release to include the the registers[]
2896 compatibility module that allowed out-of-date configurations to
2897 continue to work. This change directly impacts the following
2907 powerpc bdm protocol
2909 Unless there is activity to revive these configurations, they will be
2910 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2912 * OBSOLETE configurations and files
2914 Configurations that have been declared obsolete in this release have
2915 been commented out. Unless there is activity to revive these
2916 configurations, the next release of GDB will have their sources
2917 permanently REMOVED.
2926 *** Changes in GDB 6.2.1:
2928 * MIPS `break main; run' gave an heuristic-fence-post warning
2930 When attempting to run even a simple program, a warning about
2931 heuristic-fence-post being hit would be reported. This problem has
2934 * MIPS IRIX 'long double' crashed GDB
2936 When examining a long double variable, GDB would get a segmentation
2937 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2938 IRIX long double values).
2942 A bug in the VAX stack code was causing problems with the "next"
2943 command. This problem has been fixed.
2945 *** Changes in GDB 6.2:
2947 * Fix for ``many threads''
2949 On GNU/Linux systems that use the NPTL threads library, a program
2950 rapidly creating and deleting threads would confuse GDB leading to the
2953 ptrace: No such process.
2954 thread_db_get_info: cannot get thread info: generic error
2956 This problem has been fixed.
2958 * "-async" and "-noasync" options removed.
2960 Support for the broken "-noasync" option has been removed (it caused
2963 * New ``start'' command.
2965 This command runs the program until the begining of the main procedure.
2967 * New BSD Kernel Data Access Library (libkvm) interface
2969 Using ``target kvm'' it is now possible to debug kernel core dumps and
2970 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2971 platforms. Currently supported (native-only) configurations are:
2973 FreeBSD/amd64 x86_64-*-freebsd*
2974 FreeBSD/i386 i?86-*-freebsd*
2975 NetBSD/i386 i?86-*-netbsd*
2976 NetBSD/m68k m68*-*-netbsd*
2977 NetBSD/sparc sparc-*-netbsd*
2978 OpenBSD/amd64 x86_64-*-openbsd*
2979 OpenBSD/i386 i?86-*-openbsd*
2980 OpenBSD/m68k m68*-openbsd*
2981 OpenBSD/sparc sparc-*-openbsd*
2983 * Signal trampoline code overhauled
2985 Many generic problems with GDB's signal handling code have been fixed.
2986 These include: backtraces through non-contiguous stacks; recognition
2987 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2988 call; backtrace through a signal trampoline; step into and out of
2989 signal handlers; and single-stepping in the signal trampoline.
2991 Please note that kernel bugs are a limiting factor here. These
2992 features have been shown to work on an s390 GNU/Linux system that
2993 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2995 * Cygwin support for DWARF 2 added.
2997 * New native configurations
2999 GNU/Linux/hppa hppa*-*-linux*
3000 OpenBSD/hppa hppa*-*-openbsd*
3001 OpenBSD/m68k m68*-*-openbsd*
3002 OpenBSD/m88k m88*-*-openbsd*
3003 OpenBSD/powerpc powerpc-*-openbsd*
3004 NetBSD/vax vax-*-netbsd*
3005 OpenBSD/vax vax-*-openbsd*
3007 * END-OF-LIFE frame compatibility module
3009 GDB's internal frame infrastructure has been completely rewritten.
3010 The new infrastructure making it possible to support key new features
3011 including DWARF 2 Call Frame Information. To aid in the task of
3012 migrating old configurations to this new infrastructure, a
3013 compatibility module, that allowed old configurations to continue to
3014 work, was also included.
3016 GDB 6.2 will be the last release to include this frame compatibility
3017 module. This change directly impacts the following configurations:
3027 Unless there is activity to revive these configurations, they will be
3028 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3030 * REMOVED configurations and files
3032 Sun 3, running SunOS 3 m68*-*-sunos3*
3033 Sun 3, running SunOS 4 m68*-*-sunos4*
3034 Sun 2, running SunOS 3 m68000-*-sunos3*
3035 Sun 2, running SunOS 4 m68000-*-sunos4*
3036 Motorola 680x0 running LynxOS m68*-*-lynxos*
3037 AT&T 3b1/Unix pc m68*-att-*
3038 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3039 decstation mips-dec-* mips-little-*
3040 riscos mips-*-riscos* mips-*-sysv*
3041 sonymips mips-sony-*
3042 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3044 *** Changes in GDB 6.1.1:
3046 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3048 The TUI (Text-mode User Interface) is now built as part of a default
3049 GDB configuration. It is enabled by either selecting the TUI with the
3050 command line option "-i=tui" or by running the separate "gdbtui"
3051 program. For more information on the TUI, see the manual "Debugging
3054 * Pending breakpoint support (also included in GDB 6.1)
3056 Support has been added to allow you to specify breakpoints in shared
3057 libraries that have not yet been loaded. If a breakpoint location
3058 cannot be found, and the "breakpoint pending" option is set to auto,
3059 GDB queries you if you wish to make the breakpoint pending on a future
3060 shared-library load. If and when GDB resolves the breakpoint symbol,
3061 the pending breakpoint is removed as one or more regular breakpoints
3064 Pending breakpoints are very useful for GCJ Java debugging.
3066 * Fixed ISO-C build problems
3068 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3069 non ISO-C code that stopped them being built using a more strict ISO-C
3070 compiler (e.g., IBM's C compiler).
3072 * Fixed build problem on IRIX 5
3074 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3075 wasn't able to compile compile on an IRIX 5 system.
3077 * Added execute permission to gdb/gdbserver/configure
3079 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3080 permission. This bug would cause configure to fail on a number of
3081 systems (Solaris, IRIX). Ref: server/519.
3083 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3085 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3086 has been updated to use constant array sizes.
3088 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3090 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3091 its generated DWARF Call Frame Info. This encoding was causing GDB to
3092 panic, that panic has been fixed. Ref: gdb/1628.
3094 * Fixed a problem when examining parameters in shared library code.
3096 When examining parameters in optimized shared library code generated
3097 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3098 not available''. GDB now correctly displays the variable's value.
3100 *** Changes in GDB 6.1:
3102 * Removed --with-mmalloc
3104 Support for the mmalloc memory manager has been removed, as it
3105 conflicted with the internal gdb byte cache.
3107 * Changes in AMD64 configurations
3109 The AMD64 target now includes the %cs and %ss registers. As a result
3110 the AMD64 remote protocol has changed; this affects the floating-point
3111 and SSE registers. If you rely on those registers for your debugging,
3112 you should upgrade gdbserver on the remote side.
3114 * Revised SPARC target
3116 The SPARC target has been completely revised, incorporating the
3117 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3118 support for LynxOS and SunOS 4 has been dropped. Calling functions
3119 from within GDB on operating systems with a non-executable stack
3120 (Solaris, OpenBSD) now works.
3124 GDB has a new C++ demangler which does a better job on the mangled
3125 names generated by current versions of g++. It also runs faster, so
3126 with this and other changes gdb should now start faster on large C++
3129 * DWARF 2 Location Expressions
3131 GDB support for location expressions has been extended to support function
3132 arguments and frame bases. Older versions of GDB could crash when they
3135 * C++ nested types and namespaces
3137 GDB's support for nested types and namespaces in C++ has been
3138 improved, especially if you use the DWARF 2 debugging format. (This
3139 is the default for recent versions of GCC on most platforms.)
3140 Specifically, if you have a class "Inner" defined within a class or
3141 namespace "Outer", then GDB realizes that the class's name is
3142 "Outer::Inner", not simply "Inner". This should greatly reduce the
3143 frequency of complaints about not finding RTTI symbols. In addition,
3144 if you are stopped at inside of a function defined within a namespace,
3145 GDB modifies its name lookup accordingly.
3147 * New native configurations
3149 NetBSD/amd64 x86_64-*-netbsd*
3150 OpenBSD/amd64 x86_64-*-openbsd*
3151 OpenBSD/alpha alpha*-*-openbsd*
3152 OpenBSD/sparc sparc-*-openbsd*
3153 OpenBSD/sparc64 sparc64-*-openbsd*
3155 * New debugging protocols
3157 M32R with SDI protocol m32r-*-elf*
3159 * "set prompt-escape-char" command deleted.
3161 The command "set prompt-escape-char" has been deleted. This command,
3162 and its very obscure effet on GDB's prompt, was never documented,
3163 tested, nor mentioned in the NEWS file.
3165 * OBSOLETE configurations and files
3167 Configurations that have been declared obsolete in this release have
3168 been commented out. Unless there is activity to revive these
3169 configurations, the next release of GDB will have their sources
3170 permanently REMOVED.
3172 Sun 3, running SunOS 3 m68*-*-sunos3*
3173 Sun 3, running SunOS 4 m68*-*-sunos4*
3174 Sun 2, running SunOS 3 m68000-*-sunos3*
3175 Sun 2, running SunOS 4 m68000-*-sunos4*
3176 Motorola 680x0 running LynxOS m68*-*-lynxos*
3177 AT&T 3b1/Unix pc m68*-att-*
3178 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3179 decstation mips-dec-* mips-little-*
3180 riscos mips-*-riscos* mips-*-sysv*
3181 sonymips mips-sony-*
3182 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3184 * REMOVED configurations and files
3186 SGI Irix-4.x mips-sgi-irix4 or iris4
3187 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3188 Z8000 simulator z8k-zilog-none or z8ksim
3189 Matsushita MN10200 w/simulator mn10200-*-*
3190 H8/500 simulator h8500-hitachi-hms or h8500hms
3191 HP/PA running BSD hppa*-*-bsd*
3192 HP/PA running OSF/1 hppa*-*-osf*
3193 HP/PA Pro target hppa*-*-pro*
3194 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3195 386BSD i[3456]86-*-bsd*
3196 Sequent family i[3456]86-sequent-sysv4*
3197 i[3456]86-sequent-sysv*
3198 i[3456]86-sequent-bsd*
3199 SPARC running LynxOS sparc-*-lynxos*
3200 SPARC running SunOS 4 sparc-*-sunos4*
3201 Tsqware Sparclet sparclet-*-*
3202 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3204 *** Changes in GDB 6.0:
3208 Support for debugging the Objective-C programming language has been
3209 integrated into GDB.
3211 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3213 DWARF 2's Call Frame Information makes available compiler generated
3214 information that more exactly describes the program's run-time stack.
3215 By using this information, GDB is able to provide more robust stack
3218 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3219 have been updated to use a new backtrace mechanism which includes
3220 DWARF 2 CFI support.
3224 GDB's remote protocol has been extended to include support for hosted
3225 file I/O (where the remote target uses GDB's file system). See GDB's
3226 remote protocol documentation for details.
3228 * All targets using the new architecture framework.
3230 All of GDB's targets have been updated to use the new internal
3231 architecture framework. The way is now open for future GDB releases
3232 to include cross-architecture native debugging support (i386 on amd64,
3235 * GNU/Linux's Thread Local Storage (TLS)
3237 GDB now includes support for for the GNU/Linux implementation of
3238 per-thread variables.
3240 * GNU/Linux's Native POSIX Thread Library (NPTL)
3242 GDB's thread code has been updated to work with either the new
3243 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3245 * Separate debug info.
3247 GDB, in conjunction with BINUTILS, now supports a mechanism for
3248 automatically loading debug information from a separate file. Instead
3249 of shipping full debug and non-debug versions of system libraries,
3250 system integrators can now instead ship just the stripped libraries
3251 and optional debug files.
3253 * DWARF 2 Location Expressions
3255 DWARF 2 Location Expressions allow the compiler to more completely
3256 describe the location of variables (even in optimized code) to the
3259 GDB now includes preliminary support for location expressions (support
3260 for DW_OP_piece is still missing).
3264 A number of long standing bugs that caused GDB to die while starting a
3265 Java application have been fixed. GDB's Java support is now
3266 considered "useable".
3268 * GNU/Linux support for fork, vfork, and exec.
3270 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3271 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3274 * GDB supports logging output to a file
3276 There are two new commands, "set logging" and "show logging", which can be
3277 used to capture GDB's output to a file.
3279 * The meaning of "detach" has changed for gdbserver
3281 The "detach" command will now resume the application, as documented. To
3282 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3285 * d10v, m68hc11 `regs' command deprecated
3287 The `info registers' command has been updated so that it displays the
3288 registers using a format identical to the old `regs' command.
3292 A new command, "maint set profile on/off", has been added. This command can
3293 be used to enable or disable profiling while running GDB, to profile a
3294 session or a set of commands. In addition there is a new configure switch,
3295 "--enable-profiling", which will cause GDB to be compiled with profiling
3296 data, for more informative profiling results.
3298 * Default MI syntax changed to "mi2".
3300 The default MI (machine interface) syntax, enabled by the command line
3301 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3302 "mi1", can be enabled by specifying the option "-i=mi1".
3304 Support for the original "mi0" syntax (included in GDB 5.0) has been
3307 Fix for gdb/192: removed extraneous space when displaying frame level.
3308 Fix for gdb/672: update changelist is now output in mi list format.
3309 Fix for gdb/702: a -var-assign that updates the value now shows up
3310 in a subsequent -var-update.
3312 * New native configurations.
3314 FreeBSD/amd64 x86_64-*-freebsd*
3316 * Multi-arched targets.
3318 HP/PA HPUX11 hppa*-*-hpux*
3319 Renesas M32R/D w/simulator m32r-*-elf*
3321 * OBSOLETE configurations and files
3323 Configurations that have been declared obsolete in this release have
3324 been commented out. Unless there is activity to revive these
3325 configurations, the next release of GDB will have their sources
3326 permanently REMOVED.
3328 Z8000 simulator z8k-zilog-none or z8ksim
3329 Matsushita MN10200 w/simulator mn10200-*-*
3330 H8/500 simulator h8500-hitachi-hms or h8500hms
3331 HP/PA running BSD hppa*-*-bsd*
3332 HP/PA running OSF/1 hppa*-*-osf*
3333 HP/PA Pro target hppa*-*-pro*
3334 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3335 Sequent family i[3456]86-sequent-sysv4*
3336 i[3456]86-sequent-sysv*
3337 i[3456]86-sequent-bsd*
3338 Tsqware Sparclet sparclet-*-*
3339 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3341 * REMOVED configurations and files
3344 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3345 IBM AIX PS/2 i[3456]86-*-aix
3346 i386 running Mach 3.0 i[3456]86-*-mach3*
3347 i386 running Mach i[3456]86-*-mach*
3348 i386 running OSF/1 i[3456]86-*osf1mk*
3349 HP/Apollo 68k Family m68*-apollo*-sysv*,
3351 m68*-hp-bsd*, m68*-hp-hpux*
3352 Argonaut Risc Chip (ARC) arc-*-*
3353 Mitsubishi D30V d30v-*-*
3354 Fujitsu FR30 fr30-*-elf*
3355 OS/9000 i[34]86-*-os9k
3356 I960 with MON960 i960-*-coff
3358 * MIPS $fp behavior changed
3360 The convenience variable $fp, for the MIPS, now consistently returns
3361 the address of the current frame's base. Previously, depending on the
3362 context, $fp could refer to either $sp or the current frame's base
3363 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3364 The GNU Source-Level Debugger''.
3366 *** Changes in GDB 5.3:
3368 * GNU/Linux shared library multi-threaded performance improved.
3370 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3371 `/proc', in preference to `ptrace' for memory reads. This may result
3372 in an improvement in the start-up time of multi-threaded, shared
3373 library applications when run under GDB. One GDB user writes: ``loads
3374 shared libs like mad''.
3376 * ``gdbserver'' now supports multi-threaded applications on some targets
3378 Support for debugging multi-threaded applications which use
3379 the GNU/Linux LinuxThreads package has been added for
3380 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3381 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3383 * GDB now supports C/C++ preprocessor macros.
3385 GDB now expands preprocessor macro invocations in C/C++ expressions,
3386 and provides various commands for showing macro definitions and how
3389 The new command `macro expand EXPRESSION' expands any macro
3390 invocations in expression, and shows the result.
3392 The new command `show macro MACRO-NAME' shows the definition of the
3393 macro named MACRO-NAME, and where it was defined.
3395 Most compilers don't include information about macros in the debugging
3396 information by default. In GCC 3.1, for example, you need to compile
3397 your program with the options `-gdwarf-2 -g3'. If the macro
3398 information is present in the executable, GDB will read it.
3400 * Multi-arched targets.
3402 DEC Alpha (partial) alpha*-*-*
3403 DEC VAX (partial) vax-*-*
3405 National Semiconductor NS32000 (partial) ns32k-*-*
3406 Motorola 68000 (partial) m68k-*-*
3407 Motorola MCORE mcore-*-*
3411 Fujitsu FRV architecture added by Red Hat frv*-*-*
3414 * New native configurations
3416 Alpha NetBSD alpha*-*-netbsd*
3417 SH NetBSD sh*-*-netbsdelf*
3418 MIPS NetBSD mips*-*-netbsd*
3419 UltraSPARC NetBSD sparc64-*-netbsd*
3421 * OBSOLETE configurations and files
3423 Configurations that have been declared obsolete in this release have
3424 been commented out. Unless there is activity to revive these
3425 configurations, the next release of GDB will have their sources
3426 permanently REMOVED.
3428 Mitsubishi D30V d30v-*-*
3429 OS/9000 i[34]86-*-os9k
3430 IBM AIX PS/2 i[3456]86-*-aix
3431 Fujitsu FR30 fr30-*-elf*
3432 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3433 Argonaut Risc Chip (ARC) arc-*-*
3434 i386 running Mach 3.0 i[3456]86-*-mach3*
3435 i386 running Mach i[3456]86-*-mach*
3436 i386 running OSF/1 i[3456]86-*osf1mk*
3437 HP/Apollo 68k Family m68*-apollo*-sysv*,
3439 m68*-hp-bsd*, m68*-hp-hpux*
3440 I960 with MON960 i960-*-coff
3442 * OBSOLETE languages
3444 CHILL, a Pascal like language used by telecommunications companies.
3446 * REMOVED configurations and files
3448 AMD 29k family via UDI a29k-amd-udi, udi29k
3449 A29K VxWorks a29k-*-vxworks
3450 AMD 29000 embedded, using EBMON a29k-none-none
3451 AMD 29000 embedded with COFF a29k-none-coff
3452 AMD 29000 embedded with a.out a29k-none-aout
3454 testsuite/gdb.hp/gdb.threads-hp/ directory
3456 * New command "set max-user-call-depth <nnn>"
3458 This command allows the user to limit the call depth of user-defined
3459 commands. The default is 1024.
3461 * Changes in FreeBSD/i386 native debugging.
3463 Support for the "generate-core-file" has been added.
3465 * New commands "dump", "append", and "restore".
3467 These commands allow data to be copied from target memory
3468 to a bfd-format or binary file (dump and append), and back
3469 from a file into memory (restore).
3471 * Improved "next/step" support on multi-processor Alpha Tru64.
3473 The previous single-step mechanism could cause unpredictable problems,
3474 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3475 of a software single-step mechanism prevents this.
3477 *** Changes in GDB 5.2.1:
3485 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3486 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3487 Fix, by Joel Brobecker imported from mainline.
3489 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3490 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3491 Fix, by Fred Fish, imported from mainline.
3493 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3494 Surprisingly enough, it works now.
3495 By Michal Ludvig, imported from mainline.
3497 i386 hardware watchpoint support:
3498 avoid misses on second run for some targets.
3499 By Pierre Muller, imported from mainline.
3501 *** Changes in GDB 5.2:
3503 * New command "set trust-readonly-sections on[off]".
3505 This command is a hint that tells gdb that read-only sections
3506 really are read-only (ie. that their contents will not change).
3507 In this mode, gdb will go to the object file rather than the
3508 target to read memory from read-only sections (such as ".text").
3509 This can be a significant performance improvement on some
3510 (notably embedded) targets.
3512 * New command "generate-core-file" (or "gcore").
3514 This new gdb command allows the user to drop a core file of the child
3515 process state at any time. So far it's been implemented only for
3516 GNU/Linux and Solaris, but should be relatively easily ported to other
3517 hosts. Argument is core file name (defaults to core.<pid>).
3519 * New command line option
3521 GDB now accepts --pid or -p followed by a process id.
3523 * Change in command line behavior -- corefiles vs. process ids.
3525 There is a subtle behavior in the way in which GDB handles
3526 command line arguments. The first non-flag argument is always
3527 a program to debug, but the second non-flag argument may either
3528 be a corefile or a process id. Previously, GDB would attempt to
3529 open the second argument as a corefile, and if that failed, would
3530 issue a superfluous error message and then attempt to attach it as
3531 a process. Now, if the second argument begins with a non-digit,
3532 it will be treated as a corefile. If it begins with a digit,
3533 GDB will attempt to attach it as a process, and if no such process
3534 is found, will then attempt to open it as a corefile.
3536 * Changes in ARM configurations.
3538 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3539 configuration is fully multi-arch.
3541 * New native configurations
3543 ARM NetBSD arm*-*-netbsd*
3544 x86 OpenBSD i[3456]86-*-openbsd*
3545 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3546 Sparc64 running FreeBSD sparc64-*-freebsd*
3550 Sanyo XStormy16 xstormy16-elf
3552 * OBSOLETE configurations and files
3554 Configurations that have been declared obsolete in this release have
3555 been commented out. Unless there is activity to revive these
3556 configurations, the next release of GDB will have their sources
3557 permanently REMOVED.
3559 AMD 29k family via UDI a29k-amd-udi, udi29k
3560 A29K VxWorks a29k-*-vxworks
3561 AMD 29000 embedded, using EBMON a29k-none-none
3562 AMD 29000 embedded with COFF a29k-none-coff
3563 AMD 29000 embedded with a.out a29k-none-aout
3565 testsuite/gdb.hp/gdb.threads-hp/ directory
3567 * REMOVED configurations and files
3569 TI TMS320C80 tic80-*-*
3571 PowerPC Solaris powerpcle-*-solaris*
3572 PowerPC Windows NT powerpcle-*-cygwin32
3573 PowerPC Netware powerpc-*-netware*
3574 Harris/CXUX m88k m88*-harris-cxux*
3575 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3576 ns32k-utek-sysv* ns32k-utek-*
3577 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3578 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3579 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3580 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3581 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3583 * Changes to command line processing
3585 The new `--args' feature can be used to specify command-line arguments
3586 for the inferior from gdb's command line.
3588 * Changes to key bindings
3590 There is a new `operate-and-get-next' function bound to `C-o'.
3592 *** Changes in GDB 5.1.1
3594 Fix compile problem on DJGPP.
3596 Fix a problem with floating-point registers on the i386 being
3599 Fix to stop GDB crashing on .debug_str debug info.
3601 Numerous documentation fixes.
3603 Numerous testsuite fixes.
3605 *** Changes in GDB 5.1:
3607 * New native configurations
3609 Alpha FreeBSD alpha*-*-freebsd*
3610 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3611 MIPS GNU/Linux mips*-*-linux*
3612 MIPS SGI Irix 6.x mips*-sgi-irix6*
3613 ia64 AIX ia64-*-aix*
3614 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3618 Motorola 68HC11 and 68HC12 m68hc11-elf
3620 UltraSparc running GNU/Linux sparc64-*-linux*
3622 * OBSOLETE configurations and files
3624 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3625 Harris/CXUX m88k m88*-harris-cxux*
3626 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3627 ns32k-utek-sysv* ns32k-utek-*
3628 TI TMS320C80 tic80-*-*
3630 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3631 PowerPC Solaris powerpcle-*-solaris*
3632 PowerPC Windows NT powerpcle-*-cygwin32
3633 PowerPC Netware powerpc-*-netware*
3634 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3635 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3636 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3637 Apple Macintosh (MPW) host N/A
3639 stuff.c (Program to stuff files into a specially prepared space in kdb)
3640 kdb-start.c (Main loop for the standalone kernel debugger)
3642 Configurations that have been declared obsolete in this release have
3643 been commented out. Unless there is activity to revive these
3644 configurations, the next release of GDB will have their sources
3645 permanently REMOVED.
3647 * REMOVED configurations and files
3649 Altos 3068 m68*-altos-*
3650 Convex c1-*-*, c2-*-*
3652 ARM RISCix arm-*-* (as host)
3656 * GDB has been converted to ISO C.
3658 GDB's source code has been converted to ISO C. In particular, the
3659 sources are fully protoized, and rely on standard headers being
3664 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3666 * The MI enabled by default.
3668 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3669 revised and enabled by default. Packages which use GDB as a debugging
3670 engine behind a UI or another front end are encouraged to switch to
3671 using the GDB/MI interface, instead of the old annotations interface
3672 which is now deprecated.
3674 * Support for debugging Pascal programs.
3676 GDB now includes support for debugging Pascal programs. The following
3677 main features are supported:
3679 - Pascal-specific data types such as sets;
3681 - automatic recognition of Pascal sources based on file-name
3684 - Pascal-style display of data types, variables, and functions;
3686 - a Pascal expression parser.
3688 However, some important features are not yet supported.
3690 - Pascal string operations are not supported at all;
3692 - there are some problems with boolean types;
3694 - Pascal type hexadecimal constants are not supported
3695 because they conflict with the internal variables format;
3697 - support for Pascal objects and classes is not full yet;
3699 - unlike Pascal, GDB is case-sensitive for symbol names.
3701 * Changes in completion.
3703 Commands such as `shell', `run' and `set args', which pass arguments
3704 to inferior programs, now complete on file names, similar to what
3705 users expect at the shell prompt.
3707 Commands which accept locations, such as `disassemble', `print',
3708 `breakpoint', `until', etc. now complete on filenames as well as
3709 program symbols. Thus, if you type "break foob TAB", and the source
3710 files linked into the programs include `foobar.c', that file name will
3711 be one of the candidates for completion. However, file names are not
3712 considered for completion after you typed a colon that delimits a file
3713 name from a name of a function in that file, as in "break foo.c:bar".
3715 `set demangle-style' completes on available demangling styles.
3717 * New platform-independent commands:
3719 It is now possible to define a post-hook for a command as well as a
3720 hook that runs before the command. For more details, see the
3721 documentation of `hookpost' in the GDB manual.
3723 * Changes in GNU/Linux native debugging.
3725 Support for debugging multi-threaded programs has been completely
3726 revised for all platforms except m68k and sparc. You can now debug as
3727 many threads as your system allows you to have.
3729 Attach/detach is supported for multi-threaded programs.
3731 Support for SSE registers was added for x86. This doesn't work for
3732 multi-threaded programs though.
3734 * Changes in MIPS configurations.
3736 Multi-arch support is enabled for all MIPS configurations.
3738 GDB can now be built as native debugger on SGI Irix 6.x systems for
3739 debugging n32 executables. (Debugging 64-bit executables is not yet
3742 * Unified support for hardware watchpoints in all x86 configurations.
3744 Most (if not all) native x86 configurations support hardware-assisted
3745 breakpoints and watchpoints in a unified manner. This support
3746 implements debug register sharing between watchpoints, which allows to
3747 put a virtually infinite number of watchpoints on the same address,
3748 and also supports watching regions up to 16 bytes with several debug
3751 The new maintenance command `maintenance show-debug-regs' toggles
3752 debugging print-outs in functions that insert, remove, and test
3753 watchpoints and hardware breakpoints.
3755 * Changes in the DJGPP native configuration.
3757 New command ``info dos sysinfo'' displays assorted information about
3758 the CPU, OS, memory, and DPMI server.
3760 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3761 display information about segment descriptors stored in GDT, LDT, and
3764 New commands ``info dos pde'' and ``info dos pte'' display entries
3765 from Page Directory and Page Tables (for now works with CWSDPMI only).
3766 New command ``info dos address-pte'' displays the Page Table entry for
3767 a given linear address.
3769 GDB can now pass command lines longer than 126 characters to the
3770 program being debugged (requires an update to the libdbg.a library
3771 which is part of the DJGPP development kit).
3773 DWARF2 debug info is now supported.
3775 It is now possible to `step' and `next' through calls to `longjmp'.
3777 * Changes in documentation.
3779 All GDB documentation was converted to GFDL, the GNU Free
3780 Documentation License.
3782 Tracepoints-related commands are now fully documented in the GDB
3785 TUI, the Text-mode User Interface, is now documented in the manual.
3787 Tracepoints-related commands are now fully documented in the GDB
3790 The "GDB Internals" manual now has an index. It also includes
3791 documentation of `ui_out' functions, GDB coding standards, x86
3792 hardware watchpoints, and memory region attributes.
3794 * GDB's version number moved to ``version.in''
3796 The Makefile variable VERSION has been replaced by the file
3797 ``version.in''. People creating GDB distributions should update the
3798 contents of this file.
3802 GUD support is now a standard part of the EMACS distribution.
3804 *** Changes in GDB 5.0:
3806 * Improved support for debugging FP programs on x86 targets
3808 Unified and much-improved support for debugging floating-point
3809 programs on all x86 targets. In particular, ``info float'' now
3810 displays the FP registers in the same format on all x86 targets, with
3811 greater level of detail.
3813 * Improvements and bugfixes in hardware-assisted watchpoints
3815 It is now possible to watch array elements, struct members, and
3816 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3817 on x86 targets no longer erroneously trigger when the address is
3820 * Improvements in the native DJGPP version of GDB
3822 The distribution now includes all the scripts and auxiliary files
3823 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3824 machines ``out of the box''.
3826 The DJGPP version can now debug programs that use signals. It is
3827 possible to catch signals that happened in the debuggee, deliver
3828 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3829 would kill the program being debugged.) Programs that hook hardware
3830 interrupts (keyboard, timer, etc.) can also be debugged.
3832 It is now possible to debug DJGPP programs that redirect their
3833 standard handles or switch them to raw (as opposed to cooked) mode, or
3834 even close them. The command ``run < foo > bar'' works as expected,
3835 and ``info terminal'' reports useful information about the debuggee's
3836 terminal, including raw/cooked mode, redirection, etc.
3838 The DJGPP version now uses termios functions for console I/O, which
3839 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3842 DOS-style file names with drive letters are now fully supported by
3845 It is now possible to debug DJGPP programs that switch their working
3846 directory. It is also possible to rerun the debuggee any number of
3847 times without restarting GDB; thus, you can use the same setup,
3848 breakpoints, etc. for many debugging sessions.
3850 * New native configurations
3852 ARM GNU/Linux arm*-*-linux*
3853 PowerPC GNU/Linux powerpc-*-linux*
3857 Motorola MCore mcore-*-*
3858 x86 VxWorks i[3456]86-*-vxworks*
3859 PowerPC VxWorks powerpc-*-vxworks*
3860 TI TMS320C80 tic80-*-*
3862 * OBSOLETE configurations
3864 Altos 3068 m68*-altos-*
3865 Convex c1-*-*, c2-*-*
3867 ARM RISCix arm-*-* (as host)
3870 Configurations that have been declared obsolete will be commented out,
3871 but the code will be left in place. If there is no activity to revive
3872 these configurations before the next release of GDB, the sources will
3873 be permanently REMOVED.
3875 * Gould support removed
3877 Support for the Gould PowerNode and NP1 has been removed.
3879 * New features for SVR4
3881 On SVR4 native platforms (such as Solaris), if you attach to a process
3882 without first loading a symbol file, GDB will now attempt to locate and
3883 load symbols from the running process's executable file.
3885 * Many C++ enhancements
3887 C++ support has been greatly improved. Overload resolution now works properly
3888 in almost all cases. RTTI support is on the way.
3890 * Remote targets can connect to a sub-program
3892 A popen(3) style serial-device has been added. This device starts a
3893 sub-process (such as a stand-alone simulator) and then communicates
3894 with that. The sub-program to run is specified using the syntax
3895 ``|<program> <args>'' vis:
3897 (gdb) set remotedebug 1
3898 (gdb) target extended-remote |mn10300-elf-sim program-args
3900 * MIPS 64 remote protocol
3902 A long standing bug in the mips64 remote protocol where by GDB
3903 expected certain 32 bit registers (ex SR) to be transfered as 32
3904 instead of 64 bits has been fixed.
3906 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3907 added to provide backward compatibility with older versions of GDB.
3909 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3911 The command ``set remotebinarydownload'' command has been replaced by
3912 ``set remote X-packet''. Other commands in ``set remote'' family
3913 include ``set remote P-packet''.
3915 * Breakpoint commands accept ranges.
3917 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3918 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3919 ``tracepoint passcount'' also accepts a range of tracepoints.
3921 * ``apropos'' command added.
3923 The ``apropos'' command searches through command names and
3924 documentation strings, printing out matches, making it much easier to
3925 try to find a command that does what you are looking for.
3929 A new machine oriented interface (MI) has been added to GDB. This
3930 interface is designed for debug environments running GDB as a separate
3931 process. This is part of the long term libGDB project. See the
3932 "GDB/MI" chapter of the GDB manual for further information. It can be
3933 enabled by configuring with:
3935 .../configure --enable-gdbmi
3937 *** Changes in GDB-4.18:
3939 * New native configurations
3941 HP-UX 10.20 hppa*-*-hpux10.20
3942 HP-UX 11.x hppa*-*-hpux11.0*
3943 M68K GNU/Linux m68*-*-linux*
3947 Fujitsu FR30 fr30-*-elf*
3948 Intel StrongARM strongarm-*-*
3949 Mitsubishi D30V d30v-*-*
3951 * OBSOLETE configurations
3953 Gould PowerNode, NP1 np1-*-*, pn-*-*
3955 Configurations that have been declared obsolete will be commented out,
3956 but the code will be left in place. If there is no activity to revive
3957 these configurations before the next release of GDB, the sources will
3958 be permanently REMOVED.
3962 As a compatibility experiment, GDB's source files buildsym.h and
3963 buildsym.c have been converted to pure standard C, no longer
3964 containing any K&R compatibility code. We believe that all systems in
3965 use today either come with a standard C compiler, or have a GCC port
3966 available. If this is not true, please report the affected
3967 configuration to bug-gdb@gnu.org immediately. See the README file for
3968 information about getting a standard C compiler if you don't have one
3973 GDB now uses readline 2.2.
3975 * set extension-language
3977 You can now control the mapping between filename extensions and source
3978 languages by using the `set extension-language' command. For instance,
3979 you can ask GDB to treat .c files as C++ by saying
3980 set extension-language .c c++
3981 The command `info extensions' lists all of the recognized extensions
3982 and their associated languages.
3984 * Setting processor type for PowerPC and RS/6000
3986 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3987 you can use the `set processor' command to specify what variant of the
3988 PowerPC family you are debugging. The command
3992 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3993 following PowerPC and RS6000 variants:
3995 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3996 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3998 403GC IBM PowerPC 403GC
3999 505 Motorola PowerPC 505
4000 860 Motorola PowerPC 860 or 850
4001 601 Motorola PowerPC 601
4002 602 Motorola PowerPC 602
4003 603 Motorola/IBM PowerPC 603 or 603e
4004 604 Motorola PowerPC 604 or 604e
4005 750 Motorola/IBM PowerPC 750 or 750
4007 At the moment, this command just tells GDB what to name the
4008 special-purpose processor registers. Since almost all the affected
4009 registers are inaccessible to user-level programs, this command is
4010 only useful for remote debugging in its present form.
4014 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4015 more extensive support for HP-UX. Added features include shared
4016 library support, kernel threads and hardware watchpoints for 11.00,
4017 support for HP's ANSI C and C++ compilers, and a compatibility mode
4018 for xdb and dbx commands.
4022 HP's donation includes the new concept of catchpoints, which is a
4023 generalization of the old catch command. On HP-UX, it is now possible
4024 to catch exec, fork, and vfork, as well as library loading.
4026 This means that the existing catch command has changed; its first
4027 argument now specifies the type of catch to be set up. See the
4028 output of "help catch" for a list of catchpoint types.
4030 * Debugging across forks
4032 On HP-UX, you can choose which process to debug when a fork() happens
4037 HP has donated a curses-based terminal user interface (TUI). To get
4038 it, build with --enable-tui. Although this can be enabled for any
4039 configuration, at present it only works for native HP debugging.
4041 * GDB remote protocol additions
4043 A new protocol packet 'X' that writes binary data is now available.
4044 Default behavior is to try 'X', then drop back to 'M' if the stub
4045 fails to respond. The settable variable `remotebinarydownload'
4046 allows explicit control over the use of 'X'.
4048 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4049 full 64-bit address. The command
4051 set remoteaddresssize 32
4053 can be used to revert to the old behaviour. For existing remote stubs
4054 the change should not be noticed, as the additional address information
4057 In order to assist in debugging stubs, you may use the maintenance
4058 command `packet' to send any text string to the stub. For instance,
4060 maint packet heythere
4062 sends the packet "$heythere#<checksum>". Note that it is very easy to
4063 disrupt a debugging session by sending the wrong packet at the wrong
4066 The compare-sections command allows you to compare section data on the
4067 target to what is in the executable file without uploading or
4068 downloading, by comparing CRC checksums.
4070 * Tracing can collect general expressions
4072 You may now collect general expressions at tracepoints. This requires
4073 further additions to the target-side stub; see tracepoint.c and
4074 doc/agentexpr.texi for further details.
4076 * mask-address variable for Mips
4078 For Mips targets, you may control the zeroing of the upper 32 bits of
4079 a 64-bit address by entering `set mask-address on'. This is mainly
4080 of interest to users of embedded R4xxx and R5xxx processors.
4082 * Higher serial baud rates
4084 GDB's serial code now allows you to specify baud rates 57600, 115200,
4085 230400, and 460800 baud. (Note that your host system may not be able
4086 to achieve all of these rates.)
4090 The i960 configuration now includes an initial implementation of a
4091 builtin simulator, contributed by Jim Wilson.
4094 *** Changes in GDB-4.17:
4096 * New native configurations
4098 Alpha GNU/Linux alpha*-*-linux*
4099 Unixware 2.x i[3456]86-unixware2*
4100 Irix 6.x mips*-sgi-irix6*
4101 PowerPC GNU/Linux powerpc-*-linux*
4102 PowerPC Solaris powerpcle-*-solaris*
4103 Sparc GNU/Linux sparc-*-linux*
4104 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4108 Argonaut Risc Chip (ARC) arc-*-*
4109 Hitachi H8/300S h8300*-*-*
4110 Matsushita MN10200 w/simulator mn10200-*-*
4111 Matsushita MN10300 w/simulator mn10300-*-*
4112 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4113 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4114 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4115 Mitsubishi D10V w/simulator d10v-*-*
4116 Mitsubishi M32R/D w/simulator m32r-*-elf*
4117 Tsqware Sparclet sparclet-*-*
4118 NEC V850 w/simulator v850-*-*
4120 * New debugging protocols
4122 ARM with RDI protocol arm*-*-*
4123 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4124 DDB and LSI variants of PMON protocol mips*-*-*
4125 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4126 PowerPC with SDS protocol powerpc{,le}-*-eabi
4127 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4131 All configurations can now understand and use the DWARF 2 debugging
4132 format. The choice is automatic, if the symbol file contains DWARF 2
4137 GDB now includes basic Java language support. This support is
4138 only useful with Java compilers that produce native machine code.
4140 * solib-absolute-prefix and solib-search-path
4142 For SunOS and SVR4 shared libraries, you may now set the prefix for
4143 loading absolute shared library symbol files, and the search path for
4144 locating non-absolute shared library symbol files.
4146 * Live range splitting
4148 GDB can now effectively debug code for which GCC has performed live
4149 range splitting as part of its optimization. See gdb/doc/LRS for
4150 more details on the expected format of the stabs information.
4154 GDB's support for the GNU Hurd, including thread debugging, has been
4155 updated to work with current versions of the Hurd.
4159 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4160 instruction set. ARM GDB automatically detects when Thumb
4161 instructions are in use, and adjusts disassembly and backtracing
4166 GDB's MIPS target configurations now handle the MIP16 16-bit
4171 GDB now includes support for overlays; if an executable has been
4172 linked such that multiple sections are based at the same address, GDB
4173 will decide which section to use for symbolic info. You can choose to
4174 control the decision manually, using overlay commands, or implement
4175 additional target-side support and use "overlay load-target" to bring
4176 in the overlay mapping. Do "help overlay" for more detail.
4180 The command "info symbol <address>" displays information about
4181 the symbol at the specified address.
4185 The standard remote protocol now includes an extension that allows
4186 asynchronous collection and display of trace data. This requires
4187 extensive support in the target-side debugging stub. Tracing mode
4188 includes a new interaction mode in GDB and new commands: see the
4189 file tracepoint.c for more details.
4193 Configurations for embedded MIPS now include a simulator contributed
4194 by Cygnus Solutions. The simulator supports the instruction sets
4195 of most MIPS variants.
4199 Sparc configurations may now include the ERC32 simulator contributed
4200 by the European Space Agency. The simulator is not built into
4201 Sparc targets by default; configure with --enable-sim to include it.
4205 For target configurations that may include multiple variants of a
4206 basic architecture (such as MIPS and SH), you may now set the
4207 architecture explicitly. "set arch" sets, "info arch" lists
4208 the possible architectures.
4210 *** Changes in GDB-4.16:
4212 * New native configurations
4214 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4215 M68K NetBSD m68k-*-netbsd*
4216 PowerPC AIX 4.x powerpc-*-aix*
4217 PowerPC MacOS powerpc-*-macos*
4218 PowerPC Windows NT powerpcle-*-cygwin32
4219 RS/6000 AIX 4.x rs6000-*-aix4*
4223 ARM with RDP protocol arm-*-*
4224 I960 with MON960 i960-*-coff
4225 MIPS VxWorks mips*-*-vxworks*
4226 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4227 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4229 Matra Sparclet sparclet-*-*
4233 The powerpc-eabi configuration now includes the PSIM simulator,
4234 contributed by Andrew Cagney, with assistance from Mike Meissner.
4235 PSIM is a very elaborate model of the PowerPC, including not only
4236 basic instruction set execution, but also details of execution unit
4237 performance and I/O hardware. See sim/ppc/README for more details.
4241 GDB now works with Solaris 2.5.
4243 * Windows 95/NT native
4245 GDB will now work as a native debugger on Windows 95 and Windows NT.
4246 To build it from source, you must use the "gnu-win32" environment,
4247 which uses a DLL to emulate enough of Unix to run the GNU tools.
4248 Further information, binaries, and sources are available at
4249 ftp.cygnus.com, under pub/gnu-win32.
4251 * dont-repeat command
4253 If a user-defined command includes the command `dont-repeat', then the
4254 command will not be repeated if the user just types return. This is
4255 useful if the command is time-consuming to run, so that accidental
4256 extra keystrokes don't run the same command many times.
4258 * Send break instead of ^C
4260 The standard remote protocol now includes an option to send a break
4261 rather than a ^C to the target in order to interrupt it. By default,
4262 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4264 * Remote protocol timeout
4266 The standard remote protocol includes a new variable `remotetimeout'
4267 that allows you to set the number of seconds before GDB gives up trying
4268 to read from the target. The default value is 2.
4270 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4272 By default GDB will automatically keep track of objects as they are
4273 loaded and unloaded by the dynamic linker. By using the command `set
4274 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4275 when shared library events occur, thus allowing you to set breakpoints
4276 in shared libraries which are explicitly loaded by the inferior.
4278 Note this feature does not work on hpux8. On hpux9 you must link
4279 /usr/lib/end.o into your program. This feature should work
4280 automatically on hpux10.
4282 * Irix 5.x hardware watchpoint support
4284 Irix 5 configurations now support the use of hardware watchpoints.
4286 * Mips protocol "SYN garbage limit"
4288 When debugging a Mips target using the `target mips' protocol, you
4289 may set the number of characters that GDB will ignore by setting
4290 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4291 every character. The default value is 1050.
4293 * Recording and replaying remote debug sessions
4295 If you set `remotelogfile' to the name of a file, gdb will write to it
4296 a recording of a remote debug session. This recording may then be
4297 replayed back to gdb using "gdbreplay". See gdbserver/README for
4298 details. This is useful when you have a problem with GDB while doing
4299 remote debugging; you can make a recording of the session and send it
4300 to someone else, who can then recreate the problem.
4302 * Speedups for remote debugging
4304 GDB includes speedups for downloading and stepping MIPS systems using
4305 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4306 and more efficient S-record downloading.
4308 * Memory use reductions and statistics collection
4310 GDB now uses less memory and reports statistics about memory usage.
4311 Try the `maint print statistics' command, for example.
4313 *** Changes in GDB-4.15:
4315 * Psymtabs for XCOFF
4317 The symbol reader for AIX GDB now uses partial symbol tables. This
4318 can greatly improve startup time, especially for large executables.
4320 * Remote targets use caching
4322 Remote targets now use a data cache to speed up communication with the
4323 remote side. The data cache could lead to incorrect results because
4324 it doesn't know about volatile variables, thus making it impossible to
4325 debug targets which use memory mapped I/O devices. `set remotecache
4326 off' turns the the data cache off.
4328 * Remote targets may have threads
4330 The standard remote protocol now includes support for multiple threads
4331 in the target system, using new protocol commands 'H' and 'T'. See
4332 gdb/remote.c for details.
4336 If GDB is configured with `--enable-netrom', then it will include
4337 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4338 acts as though it is a bank of ROM on the target board, but you can
4339 write into it over the network. GDB's support consists only of
4340 support for fast loading into the emulated ROM; to debug, you must use
4341 another protocol, such as standard remote protocol. The usual
4342 sequence is something like
4344 target nrom <netrom-hostname>
4346 target remote <netrom-hostname>:1235
4350 GDB now includes support for the Apple Macintosh, as a host only. It
4351 may be run as either an MPW tool or as a standalone application, and
4352 it can debug through the serial port. All the usual GDB commands are
4353 available, but to the target command, you must supply "serial" as the
4354 device type instead of "/dev/ttyXX". See mpw-README in the main
4355 directory for more information on how to build. The MPW configuration
4356 scripts */mpw-config.in support only a few targets, and only the
4357 mips-idt-ecoff target has been tested.
4361 GDB configuration now uses autoconf. This is not user-visible,
4362 but does simplify configuration and building.
4366 GDB now supports hpux10.
4368 *** Changes in GDB-4.14:
4370 * New native configurations
4372 x86 FreeBSD i[345]86-*-freebsd
4373 x86 NetBSD i[345]86-*-netbsd
4374 NS32k NetBSD ns32k-*-netbsd
4375 Sparc NetBSD sparc-*-netbsd
4379 A29K VxWorks a29k-*-vxworks
4380 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4381 CPU32 EST-300 emulator m68*-*-est*
4382 PowerPC ELF powerpc-*-elf
4385 * Alpha OSF/1 support for procfs
4387 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4388 possible to attach to running processes. As the mounting of the /proc
4389 filesystem is optional on the Alpha, GDB automatically determines
4390 the availability of /proc during startup. This can lead to problems
4391 if /proc is unmounted after GDB has been started.
4393 * Arguments to user-defined commands
4395 User commands may accept up to 10 arguments separated by whitespace.
4396 Arguments are accessed within the user command via $arg0..$arg9. A
4399 print $arg0 + $arg1 + $arg2
4401 To execute the command use:
4404 Defines the command "adder" which prints the sum of its three arguments.
4405 Note the arguments are text substitutions, so they may reference variables,
4406 use complex expressions, or even perform inferior function calls.
4408 * New `if' and `while' commands
4410 This makes it possible to write more sophisticated user-defined
4411 commands. Both commands take a single argument, which is the
4412 expression to evaluate, and must be followed by the commands to
4413 execute, one per line, if the expression is nonzero, the list being
4414 terminated by the word `end'. The `if' command list may include an
4415 `else' word, which causes the following commands to be executed only
4416 if the expression is zero.
4418 * Fortran source language mode
4420 GDB now includes partial support for Fortran 77. It will recognize
4421 Fortran programs and can evaluate a subset of Fortran expressions, but
4422 variables and functions may not be handled correctly. GDB will work
4423 with G77, but does not yet know much about symbols emitted by other
4426 * Better HPUX support
4428 Most debugging facilities now work on dynamic executables for HPPAs
4429 running hpux9 or later. You can attach to running dynamically linked
4430 processes, but by default the dynamic libraries will be read-only, so
4431 for instance you won't be able to put breakpoints in them. To change
4432 that behavior do the following before running the program:
4438 This will cause the libraries to be mapped private and read-write.
4439 To revert to the normal behavior, do this:
4445 You cannot set breakpoints or examine data in the library until after
4446 the library is loaded if the function/data symbols do not have
4449 GDB can now also read debug symbols produced by the HP C compiler on
4450 HPPAs (sorry, no C++, Fortran or 68k support).
4452 * Target byte order now dynamically selectable
4454 You can choose which byte order to use with a target system, via the
4455 commands "set endian big" and "set endian little", and you can see the
4456 current setting by using "show endian". You can also give the command
4457 "set endian auto", in which case GDB will use the byte order
4458 associated with the executable. Currently, only embedded MIPS
4459 configurations support dynamic selection of target byte order.
4461 * New DOS host serial code
4463 This version uses DPMI interrupts to handle buffered I/O, so you
4464 no longer need to run asynctsr when debugging boards connected to
4467 *** Changes in GDB-4.13:
4469 * New "complete" command
4471 This lists all the possible completions for the rest of the line, if it
4472 were to be given as a command itself. This is intended for use by emacs.
4474 * Trailing space optional in prompt
4476 "set prompt" no longer adds a space for you after the prompt you set. This
4477 allows you to set a prompt which ends in a space or one that does not.
4479 * Breakpoint hit counts
4481 "info break" now displays a count of the number of times the breakpoint
4482 has been hit. This is especially useful in conjunction with "ignore"; you
4483 can ignore a large number of breakpoint hits, look at the breakpoint info
4484 to see how many times the breakpoint was hit, then run again, ignoring one
4485 less than that number, and this will get you quickly to the last hit of
4488 * Ability to stop printing at NULL character
4490 "set print null-stop" will cause GDB to stop printing the characters of
4491 an array when the first NULL is encountered. This is useful when large
4492 arrays actually contain only short strings.
4494 * Shared library breakpoints
4496 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4497 breakpoints in shared libraries before the executable is run.
4499 * Hardware watchpoints
4501 There is a new hardware breakpoint for the watch command for sparclite
4502 targets. See gdb/sparclite/hw_breakpoint.note.
4504 Hardware watchpoints are also now supported under GNU/Linux.
4508 Annotations have been added. These are for use with graphical interfaces,
4509 and are still experimental. Currently only gdba.el uses these.
4511 * Improved Irix 5 support
4513 GDB now works properly with Irix 5.2.
4515 * Improved HPPA support
4517 GDB now works properly with the latest GCC and GAS.
4519 * New native configurations
4521 Sequent PTX4 i[34]86-sequent-ptx4
4522 HPPA running OSF/1 hppa*-*-osf*
4523 Atari TT running SVR4 m68*-*-sysv4*
4524 RS/6000 LynxOS rs6000-*-lynxos*
4528 OS/9000 i[34]86-*-os9k
4529 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4532 * Hitachi SH7000 and E7000-PC ICE support
4534 There is now support for communicating with the Hitachi E7000-PC ICE.
4535 This is available automatically when GDB is configured for the SH.
4539 As usual, a variety of small fixes and improvements, both generic
4540 and configuration-specific. See the ChangeLog for more detail.
4542 *** Changes in GDB-4.12:
4544 * Irix 5 is now supported
4548 GDB-4.12 on the HPPA has a number of changes which make it unable
4549 to debug the output from the currently released versions of GCC and
4550 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4551 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4552 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4555 *** Changes in GDB-4.11:
4557 * User visible changes:
4561 The "set remotedebug" option is now consistent between the mips remote
4562 target, remote targets using the gdb-specific protocol, UDI (AMD's
4563 debug protocol for the 29k) and the 88k bug monitor. It is now an
4564 integer specifying a debug level (normally 0 or 1, but 2 means more
4565 debugging info for the mips target).
4567 * DEC Alpha native support
4569 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4570 debug info, but GDB works fairly well with the DEC compiler and should
4571 work with a future GCC release. See the README file for a few
4572 Alpha-specific notes.
4574 * Preliminary thread implementation
4576 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4578 * LynxOS native and target support for 386
4580 This release has been hosted on LynxOS 2.2, and also can be configured
4581 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4584 * Improvements in C++ mangling/demangling.
4586 This release has much better g++ debugging, specifically in name
4587 mangling/demangling, virtual function calls, print virtual table,
4588 call methods, ...etc.
4590 *** Changes in GDB-4.10:
4592 * User visible changes:
4594 Remote debugging using the GDB-specific (`target remote') protocol now
4595 supports the `load' command. This is only useful if you have some
4596 other way of getting the stub to the target system, and you can put it
4597 somewhere in memory where it won't get clobbered by the download.
4599 Filename completion now works.
4601 When run under emacs mode, the "info line" command now causes the
4602 arrow to point to the line specified. Also, "info line" prints
4603 addresses in symbolic form (as well as hex).
4605 All vxworks based targets now support a user settable option, called
4606 vxworks-timeout. This option represents the number of seconds gdb
4607 should wait for responses to rpc's. You might want to use this if
4608 your vxworks target is, perhaps, a slow software simulator or happens
4609 to be on the far side of a thin network line.
4613 This release contains support for using a DEC alpha as a GDB host for
4614 cross debugging. Native alpha debugging is not supported yet.
4617 *** Changes in GDB-4.9:
4621 This is the first GDB release which is accompanied by a matching testsuite.
4622 The testsuite requires installation of dejagnu, which should be available
4623 via ftp from most sites that carry GNU software.
4627 'Cfront' style demangling has had its name changed to 'ARM' style, to
4628 emphasize that it was written from the specifications in the C++ Annotated
4629 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4630 disclaimers, it still generated too much confusion with users attempting to
4631 use gdb with AT&T cfront.
4635 GDB now uses a standard remote interface to a simulator library.
4636 So far, the library contains simulators for the Zilog Z8001/2, the
4637 Hitachi H8/300, H8/500 and Super-H.
4639 * New targets supported
4641 H8/300 simulator h8300-hitachi-hms or h8300hms
4642 H8/500 simulator h8500-hitachi-hms or h8500hms
4643 SH simulator sh-hitachi-hms or sh
4644 Z8000 simulator z8k-zilog-none or z8ksim
4645 IDT MIPS board over serial line mips-idt-ecoff
4647 Cross-debugging to GO32 targets is supported. It requires a custom
4648 version of the i386-stub.c module which is integrated with the
4649 GO32 memory extender.
4651 * New remote protocols
4653 MIPS remote debugging protocol.
4655 * New source languages supported
4657 This version includes preliminary support for Chill, a Pascal like language
4658 used by telecommunications companies. Chill support is also being integrated
4659 into the GNU compiler, but we don't know when it will be publically available.
4662 *** Changes in GDB-4.8:
4664 * HP Precision Architecture supported
4666 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4667 version of this support was available as a set of patches from the
4668 University of Utah. GDB does not support debugging of programs
4669 compiled with the HP compiler, because HP will not document their file
4670 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4671 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4673 Many problems in the preliminary version have been fixed.
4675 * Faster and better demangling
4677 We have improved template demangling and fixed numerous bugs in the GNU style
4678 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4679 character types (wchar_t) are now supported. Demangling of each symbol is now
4680 only done once, and is cached when the symbol table for a file is read in.
4681 This results in a small increase in memory usage for C programs, a moderate
4682 increase in memory usage for C++ programs, and a fantastic speedup in
4685 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4686 from the specifications in the Annotated Reference Manual, which AT&T's
4687 compiler does not actually implement.
4689 * G++ multiple inheritance compiler problem
4691 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4692 inheritance lattices was reworked to properly discover ambiguities. We
4693 recently found an example which causes this new algorithm to fail in a
4694 very subtle way, producing bad debug information for those classes.
4695 The file 'gcc.patch' (in this directory) can be applied to gcc to
4696 circumvent the problem. A future GCC release will contain a complete
4699 The previous G++ debug info problem (mentioned below for the gdb-4.7
4700 release) is fixed in gcc version 2.3.2.
4702 * Improved configure script
4704 The `configure' script will now attempt to guess your system type if
4705 you don't supply a host system type. The old scheme of supplying a
4706 host system triplet is preferable over using this. All the magic is
4707 done in the new `config.guess' script. Examine it for details.
4709 We have also brought our configure script much more in line with the FSF's
4710 version. It now supports the --with-xxx options. In particular,
4711 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4712 The resulting GDB will not be able to read arbitrary object file formats --
4713 only the format ``expected'' to be used on the configured target system.
4714 We hope to make this the default in a future release.
4716 * Documentation improvements
4718 There's new internal documentation on how to modify GDB, and how to
4719 produce clean changes to the code. We implore people to read it
4720 before submitting changes.
4722 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4723 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4724 `info' files are also provided. To build `info' files from scratch,
4725 you will need the latest `makeinfo' release, which will be available in
4726 a future texinfo-X.Y release.
4728 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4729 We're not sure exactly which versions have this problem, but it has
4730 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4731 or better. If that isn't possible, there is a patch in
4732 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4733 around this problem.
4737 GDB now supports array constants that can be used in expressions typed in by
4738 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4739 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4742 The new directory `gdb/sparclite' contains a program that demonstrates
4743 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4745 * New native hosts supported
4747 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4748 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4750 * New targets supported
4752 AMD 29k family via UDI a29k-amd-udi or udi29k
4754 * New file formats supported
4756 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4757 HPUX core files, and SCO 3.2v2 core files.
4761 Attaching to processes now works again; thanks for the many bug reports.
4763 We have also stomped on a bunch of core dumps caused by
4764 printf_filtered("%s") problems.
4766 We eliminated a copyright problem on the rpc and ptrace header files
4767 for VxWorks, which was discovered at the last minute during the 4.7
4768 release. You should now be able to build a VxWorks GDB.
4770 You can now interrupt gdb while an attached process is running. This
4771 will cause the attached process to stop, and give control back to GDB.
4773 We fixed problems caused by using too many file descriptors
4774 for reading symbols from object files and libraries. This was
4775 especially a problem for programs that used many (~100) shared
4778 The `step' command now only enters a subroutine if there is line number
4779 information for the subroutine. Otherwise it acts like the `next'
4780 command. Previously, `step' would enter subroutines if there was
4781 any debugging information about the routine. This avoids problems
4782 when using `cc -g1' on MIPS machines.
4784 * Internal improvements
4786 GDB's internal interfaces have been improved to make it easier to support
4787 debugging of multiple languages in the future.
4789 GDB now uses a common structure for symbol information internally.
4790 Minimal symbols (derived from linkage symbols in object files), partial
4791 symbols (from a quick scan of debug information), and full symbols
4792 contain a common subset of information, making it easier to write
4793 shared code that handles any of them.
4795 * New command line options
4797 We now accept --silent as an alias for --quiet.
4801 The memory-mapped-malloc library is now licensed under the GNU Library
4802 General Public License.
4804 *** Changes in GDB-4.7:
4806 * Host/native/target split
4808 GDB has had some major internal surgery to untangle the support for
4809 hosts and remote targets. Now, when you configure GDB for a remote
4810 target, it will no longer load in all of the support for debugging
4811 local programs on the host. When fully completed and tested, this will
4812 ensure that arbitrary host/target combinations are possible.
4814 The primary conceptual shift is to separate the non-portable code in
4815 GDB into three categories. Host specific code is required any time GDB
4816 is compiled on that host, regardless of the target. Target specific
4817 code relates to the peculiarities of the target, but can be compiled on
4818 any host. Native specific code is everything else: it can only be
4819 built when the host and target are the same system. Child process
4820 handling and core file support are two common `native' examples.
4822 GDB's use of /proc for controlling Unix child processes is now cleaner.
4823 It has been split out into a single module under the `target_ops' vector,
4824 plus two native-dependent functions for each system that uses /proc.
4826 * New hosts supported
4828 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4829 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4830 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4832 * New targets supported
4834 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4835 68030 and CPU32 m68030-*-*, m68332-*-*
4837 * New native hosts supported
4839 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4840 (386bsd is not well tested yet)
4841 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4843 * New file formats supported
4845 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4846 supports reading of `a.out.adobe' object files, which are an a.out
4847 format extended with minimal information about multiple sections.
4851 `show copying' is the same as the old `info copying'.
4852 `show warranty' is the same as `info warrantee'.
4853 These were renamed for consistency. The old commands continue to work.
4855 `info handle' is a new alias for `info signals'.
4857 You can now define pre-command hooks, which attach arbitrary command
4858 scripts to any command. The commands in the hook will be executed
4859 prior to the user's command. You can also create a hook which will be
4860 executed whenever the program stops. See gdb.texinfo.
4864 We now deal with Cfront style name mangling, and can even extract type
4865 info from mangled symbols. GDB can automatically figure out which
4866 symbol mangling style your C++ compiler uses.
4868 Calling of methods and virtual functions has been improved as well.
4872 The crash that occured when debugging Sun Ansi-C compiled binaries is
4873 fixed. This was due to mishandling of the extra N_SO stabs output
4876 We also finally got Ultrix 4.2 running in house, and fixed core file
4877 support, with help from a dozen people on the net.
4879 John M. Farrell discovered that the reason that single-stepping was so
4880 slow on all of the Mips based platforms (primarily SGI and DEC) was
4881 that we were trying to demangle and lookup a symbol used for internal
4882 purposes on every instruction that was being stepped through. Changing
4883 the name of that symbol so that it couldn't be mistaken for a C++
4884 mangled symbol sped things up a great deal.
4886 Rich Pixley sped up symbol lookups in general by getting much smarter
4887 about when C++ symbol mangling is necessary. This should make symbol
4888 completion (TAB on the command line) much faster. It's not as fast as
4889 we'd like, but it's significantly faster than gdb-4.6.
4893 A new user controllable variable 'call_scratch_address' can
4894 specify the location of a scratch area to be used when GDB
4895 calls a function in the target. This is necessary because the
4896 usual method of putting the scratch area on the stack does not work
4897 in systems that have separate instruction and data spaces.
4899 We integrated changes to support the 29k UDI (Universal Debugger
4900 Interface), but discovered at the last minute that we didn't have all
4901 of the appropriate copyright paperwork. We are working with AMD to
4902 resolve this, and hope to have it available soon.
4906 We have sped up the remote serial line protocol, especially for targets
4907 with lots of registers. It now supports a new `expedited status' ('T')
4908 message which can be used in place of the existing 'S' status message.
4909 This allows the remote stub to send only the registers that GDB
4910 needs to make a quick decision about single-stepping or conditional
4911 breakpoints, eliminating the need to fetch the entire register set for
4912 each instruction being stepped through.
4914 The GDB remote serial protocol now implements a write-through cache for
4915 registers, only re-reading the registers if the target has run.
4917 There is also a new remote serial stub for SPARC processors. You can
4918 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4919 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4920 processor with a serial port.
4924 Configure.in files have become much easier to read and modify. A new
4925 `table driven' format makes it more obvious what configurations are
4926 supported, and what files each one uses.
4930 There is a new opcodes library which will eventually contain all of the
4931 disassembly routines and opcode tables. At present, it only contains
4932 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4933 disassembler (binutils/objdump) to share these routines.
4935 The libiberty library is now copylefted under the GNU Library General
4936 Public License. This allows more liberal use, and was done so libg++
4937 can use it. This makes no difference to GDB, since the Library License
4938 grants all the rights from the General Public License.
4942 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4943 reference to the stabs symbol info used by the debugger. It is (as far
4944 as we know) the only published document on this fascinating topic. We
4945 encourage you to read it, compare it to the stabs information on your
4946 system, and send improvements on the document in general (to
4947 bug-gdb@prep.ai.mit.edu).
4949 And, of course, many bugs have been fixed.
4952 *** Changes in GDB-4.6:
4954 * Better support for C++ function names
4956 GDB now accepts as input the "demangled form" of C++ overloaded function
4957 names and member function names, and can do command completion on such names
4958 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4959 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4960 Make use of command completion, it is your friend.
4962 GDB also now accepts a variety of C++ mangled symbol formats. They are
4963 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4964 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4965 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4966 for the list of formats.
4968 * G++ symbol mangling problem
4970 Recent versions of gcc have a bug in how they emit debugging information for
4971 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4972 directory) can be applied to gcc to fix the problem. Alternatively, if you
4973 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4974 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4975 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4978 * New 'maintenance' command
4980 All of the commands related to hacking GDB internals have been moved out of
4981 the main command set, and now live behind the 'maintenance' command. This
4982 can also be abbreviated as 'mt'. The following changes were made:
4984 dump-me -> maintenance dump-me
4985 info all-breakpoints -> maintenance info breakpoints
4986 printmsyms -> maintenance print msyms
4987 printobjfiles -> maintenance print objfiles
4988 printpsyms -> maintenance print psymbols
4989 printsyms -> maintenance print symbols
4991 The following commands are new:
4993 maintenance demangle Call internal GDB demangler routine to
4994 demangle a C++ link name and prints the result.
4995 maintenance print type Print a type chain for a given symbol
4997 * Change to .gdbinit file processing
4999 We now read the $HOME/.gdbinit file before processing the argv arguments
5000 (e.g. reading symbol files or core files). This allows global parameters to
5001 be set, which will apply during the symbol reading. The ./.gdbinit is still
5002 read after argv processing.
5004 * New hosts supported
5006 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5008 GNU/Linux support i386-unknown-linux or linux
5010 We are also including code to support the HP/PA running BSD and HPUX. This
5011 is almost guaranteed not to work, as we didn't have time to test or build it
5012 for this release. We are including it so that the more adventurous (or
5013 masochistic) of you can play with it. We also had major problems with the
5014 fact that the compiler that we got from HP doesn't support the -g option.
5017 * New targets supported
5019 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5021 * More smarts about finding #include files
5023 GDB now remembers the compilation directory for all include files, and for
5024 all files from which C is generated (like yacc and lex sources). This
5025 greatly improves GDB's ability to find yacc/lex sources, and include files,
5026 especially if you are debugging your program from a directory different from
5027 the one that contains your sources.
5029 We also fixed a bug which caused difficulty with listing and setting
5030 breakpoints in include files which contain C code. (In the past, you had to
5031 try twice in order to list an include file that you hadn't looked at before.)
5033 * Interesting infernals change
5035 GDB now deals with arbitrary numbers of sections, where the symbols for each
5036 section must be relocated relative to that section's landing place in the
5037 target's address space. This work was needed to support ELF with embedded
5038 stabs used by Solaris-2.0.
5040 * Bug fixes (of course!)
5042 There have been loads of fixes for the following things:
5043 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5044 i960, stabs, DOS(GO32), procfs, etc...
5046 See the ChangeLog for details.
5048 *** Changes in GDB-4.5:
5050 * New machines supported (host and target)
5052 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5054 SGI Irix-4.x mips-sgi-irix4 or iris4
5056 * New malloc package
5058 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5059 Mmalloc is capable of handling mutiple heaps of memory. It is also
5060 capable of saving a heap to a file, and then mapping it back in later.
5061 This can be used to greatly speedup the startup of GDB by using a
5062 pre-parsed symbol table which lives in a mmalloc managed heap. For
5063 more details, please read mmalloc/mmalloc.texi.
5067 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5068 'help info proc' for details.
5070 * MIPS ecoff symbol table format
5072 The code that reads MIPS symbol table format is now supported on all hosts.
5073 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5076 * File name changes for MS-DOS
5078 Many files in the config directories have been renamed to make it easier to
5079 support GDB on MS-DOSe systems (which have very restrictive file name
5080 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5081 environment) is close to working but has some remaining problems. Note
5082 that debugging of DOS programs is not supported, due to limitations
5083 in the ``operating system'', but it can be used to host cross-debugging.
5085 * Cross byte order fixes
5087 Many fixes have been made to support cross debugging of Sparc and MIPS
5088 targets from hosts whose byte order differs.
5090 * New -mapped and -readnow options
5092 If memory-mapped files are available on your system through the 'mmap'
5093 system call, you can use the -mapped option on the `file' or
5094 `symbol-file' commands to cause GDB to write the symbols from your
5095 program into a reusable file. If the program you are debugging is
5096 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5097 Future GDB debugging sessions will notice the presence of this file,
5098 and will quickly map in symbol information from it, rather than reading
5099 the symbol table from the executable program. Using the '-mapped'
5100 option in a GDB `file' or `symbol-file' command has the same effect as
5101 starting GDB with the '-mapped' command-line option.
5103 You can cause GDB to read the entire symbol table immediately by using
5104 the '-readnow' option with any of the commands that load symbol table
5105 information (or on the GDB command line). This makes the command
5106 slower, but makes future operations faster.
5108 The -mapped and -readnow options are typically combined in order to
5109 build a `fred.syms' file that contains complete symbol information.
5110 A simple GDB invocation to do nothing but build a `.syms' file for future
5113 gdb -batch -nx -mapped -readnow programname
5115 The `.syms' file is specific to the host machine on which GDB is run.
5116 It holds an exact image of GDB's internal symbol table. It cannot be
5117 shared across multiple host platforms.
5119 * longjmp() handling
5121 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5122 siglongjmp() without losing control. This feature has not yet been ported to
5123 all systems. It currently works on many 386 platforms, all MIPS-based
5124 platforms (SGI, DECstation, etc), and Sun3/4.
5128 Preliminary work has been put in to support the new Solaris OS from Sun. At
5129 this time, it can control and debug processes, but it is not capable of
5134 As always, many many bug fixes. The major areas were with g++, and mipsread.
5135 People using the MIPS-based platforms should experience fewer mysterious
5136 crashes and trashed symbol tables.
5138 *** Changes in GDB-4.4:
5140 * New machines supported (host and target)
5142 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5144 BSD Reno on Vax vax-dec-bsd
5145 Ultrix on Vax vax-dec-ultrix
5147 * New machines supported (target)
5149 AMD 29000 embedded, using EBMON a29k-none-none
5153 GDB continues to improve its handling of C++. `References' work better.
5154 The demangler has also been improved, and now deals with symbols mangled as
5155 per the Annotated C++ Reference Guide.
5157 GDB also now handles `stabs' symbol information embedded in MIPS
5158 `ecoff' symbol tables. Since the ecoff format was not easily
5159 extensible to handle new languages such as C++, this appeared to be a
5160 good way to put C++ debugging info into MIPS binaries. This option
5161 will be supported in the GNU C compiler, version 2, when it is
5164 * New features for SVR4
5166 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5167 shared libraries. Debugging dynamically linked programs should present
5168 only minor differences from debugging statically linked programs.
5170 The `info proc' command will print out information about any process
5171 on an SVR4 system (including the one you are debugging). At the moment,
5172 it prints the address mappings of the process.
5174 If you bring up GDB on another SVR4 system, please send mail to
5175 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5177 * Better dynamic linking support in SunOS
5179 Reading symbols from shared libraries which contain debugging symbols
5180 now works properly. However, there remain issues such as automatic
5181 skipping of `transfer vector' code during function calls, which
5182 make it harder to debug code in a shared library, than to debug the
5183 same code linked statically.
5187 GDB is now using the latest `getopt' routines from the FSF. This
5188 version accepts the -- prefix for options with long names. GDB will
5189 continue to accept the old forms (-option and +option) as well.
5190 Various single letter abbreviations for options have been explicity
5191 added to the option table so that they won't get overshadowed in the
5192 future by other options that begin with the same letter.
5196 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5197 Many assorted bugs have been handled. Many more remain to be handled.
5198 See the various ChangeLog files (primarily in gdb and bfd) for details.
5201 *** Changes in GDB-4.3:
5203 * New machines supported (host and target)
5205 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5206 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5207 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5209 * Almost SCO Unix support
5211 We had hoped to support:
5212 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5213 (except for core file support), but we discovered very late in the release
5214 that it has problems with process groups that render gdb unusable. Sorry
5215 about that. I encourage people to fix it and post the fixes.
5217 * Preliminary ELF and DWARF support
5219 GDB can read ELF object files on System V Release 4, and can handle
5220 debugging records for C, in DWARF format, in ELF files. This support
5221 is preliminary. If you bring up GDB on another SVR4 system, please
5222 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5227 GDB now uses the latest `readline' library. One user-visible change
5228 is that two tabs will list possible command completions, which previously
5229 required typing M-? (meta-question mark, or ESC ?).
5233 The `stepi' bug that many of you noticed has been squashed.
5234 Many bugs in C++ have been handled. Many more remain to be handled.
5235 See the various ChangeLog files (primarily in gdb and bfd) for details.
5237 * State of the MIPS world (in case you wondered):
5239 GDB can understand the symbol tables emitted by the compilers
5240 supplied by most vendors of MIPS-based machines, including DEC. These
5241 symbol tables are in a format that essentially nobody else uses.
5243 Some versions of gcc come with an assembler post-processor called
5244 mips-tfile. This program is required if you want to do source-level
5245 debugging of gcc-compiled programs. I believe FSF does not ship
5246 mips-tfile with gcc version 1, but it will eventually come with gcc
5249 Debugging of g++ output remains a problem. g++ version 1.xx does not
5250 really support it at all. (If you're lucky, you should be able to get
5251 line numbers and stack traces to work, but no parameters or local
5252 variables.) With some work it should be possible to improve the
5255 When gcc version 2 is released, you will have somewhat better luck.
5256 However, even then you will get confusing results for inheritance and
5259 We will eventually provide full debugging of g++ output on
5260 DECstations. This will probably involve some kind of stabs-in-ecoff
5261 encapulation, but the details have not been worked out yet.
5264 *** Changes in GDB-4.2:
5266 * Improved configuration
5268 Only one copy of `configure' exists now, and it is not self-modifying.
5269 Porting BFD is simpler.
5273 The `step' and `next' commands now only stop at the first instruction
5274 of a source line. This prevents the multiple stops that used to occur
5275 in switch statements, for-loops, etc. `Step' continues to stop if a
5276 function that has debugging information is called within the line.
5280 Lots of small bugs fixed. More remain.
5282 * New host supported (not target)
5284 Intel 386 PC clone running Mach i386-none-mach
5287 *** Changes in GDB-4.1:
5289 * Multiple source language support
5291 GDB now has internal scaffolding to handle several source languages.
5292 It determines the type of each source file from its filename extension,
5293 and will switch expression parsing and number formatting to match the
5294 language of the function in the currently selected stack frame.
5295 You can also specifically set the language to be used, with
5296 `set language c' or `set language modula-2'.
5300 GDB now has preliminary support for the GNU Modula-2 compiler,
5301 currently under development at the State University of New York at
5302 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5303 continue through the fall of 1991 and into 1992.
5305 Other Modula-2 compilers are currently not supported, and attempting to
5306 debug programs compiled with them will likely result in an error as the
5307 symbol table is read. Feel free to work on it, though!
5309 There are hooks in GDB for strict type checking and range checking,
5310 in the `Modula-2 philosophy', but they do not currently work.
5314 GDB can now write to executable and core files (e.g. patch
5315 a variable's value). You must turn this switch on, specify
5316 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5317 by assigning a new value to a variable. Modifications take
5320 * Automatic SunOS shared library reading
5322 When you run your program, GDB automatically determines where its
5323 shared libraries (if any) have been loaded, and reads their symbols.
5324 The `share' command is no longer needed. This also works when
5325 examining core files.
5329 You can specify the number of lines that the `list' command shows.
5332 * New machines supported (host and target)
5334 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5335 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5336 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5338 * New hosts supported (not targets)
5340 IBM RT/PC: romp-ibm-aix or rtpc
5342 * New targets supported (not hosts)
5344 AMD 29000 embedded with COFF a29k-none-coff
5345 AMD 29000 embedded with a.out a29k-none-aout
5346 Ultracomputer remote kernel debug a29k-nyu-kern
5348 * New remote interfaces
5354 *** Changes in GDB-4.0:
5358 Wide output is wrapped at good places to make the output more readable.
5360 Gdb now supports cross-debugging from a host machine of one type to a
5361 target machine of another type. Communication with the target system
5362 is over serial lines. The ``target'' command handles connecting to the
5363 remote system; the ``load'' command will download a program into the
5364 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5365 also supports debugging of realtime processes running under VxWorks,
5366 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5367 stub on the target system.
5369 New CPUs supported include the AMD 29000 and Intel 960.
5371 GDB now reads object files and symbol tables via a ``binary file''
5372 library, which allows a single copy of GDB to debug programs of multiple
5373 object file types such as a.out and coff.
5375 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5376 refcard.dvi and refcard.ps are available to format it).
5379 * Control-Variable user interface simplified
5381 All variables that control the operation of the debugger can be set
5382 by the ``set'' command, and displayed by the ``show'' command.
5384 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5385 ``Show prompt'' produces the response:
5386 Gdb's prompt is new-gdb=>.
5388 What follows are the NEW set commands. The command ``help set'' will
5389 print a complete list of old and new set commands. ``help set FOO''
5390 will give a longer description of the variable FOO. ``show'' will show
5391 all of the variable descriptions and their current settings.
5393 confirm on/off: Enables warning questions for operations that are
5394 hard to recover from, e.g. rerunning the program while
5395 it is already running. Default is ON.
5397 editing on/off: Enables EMACS style command line editing
5398 of input. Previous lines can be recalled with
5399 control-P, the current line can be edited with control-B,
5400 you can search for commands with control-R, etc.
5403 history filename NAME: NAME is where the gdb command history
5404 will be stored. The default is .gdb_history,
5405 or the value of the environment variable
5408 history size N: The size, in commands, of the command history. The
5409 default is 256, or the value of the environment variable
5412 history save on/off: If this value is set to ON, the history file will
5413 be saved after exiting gdb. If set to OFF, the
5414 file will not be saved. The default is OFF.
5416 history expansion on/off: If this value is set to ON, then csh-like
5417 history expansion will be performed on
5418 command line input. The default is OFF.
5420 radix N: Sets the default radix for input and output. It can be set
5421 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5422 in the current radix, so "set radix 10" is always a no-op.
5424 height N: This integer value is the number of lines on a page. Default
5425 is 24, the current `stty rows'' setting, or the ``li#''
5426 setting from the termcap entry matching the environment
5429 width N: This integer value is the number of characters on a line.
5430 Default is 80, the current `stty cols'' setting, or the ``co#''
5431 setting from the termcap entry matching the environment
5434 Note: ``set screensize'' is obsolete. Use ``set height'' and
5435 ``set width'' instead.
5437 print address on/off: Print memory addresses in various command displays,
5438 such as stack traces and structure values. Gdb looks
5439 more ``symbolic'' if you turn this off; it looks more
5440 ``machine level'' with it on. Default is ON.
5442 print array on/off: Prettyprint arrays. New convenient format! Default
5445 print demangle on/off: Print C++ symbols in "source" form if on,
5448 print asm-demangle on/off: Same, for assembler level printouts
5451 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5454 * Support for Epoch Environment.
5456 The epoch environment is a version of Emacs v18 with windowing. One
5457 new command, ``inspect'', is identical to ``print'', except that if you
5458 are running in the epoch environment, the value is printed in its own
5462 * Support for Shared Libraries
5464 GDB can now debug programs and core files that use SunOS shared libraries.
5465 Symbols from a shared library cannot be referenced
5466 before the shared library has been linked with the program (this
5467 happens after you type ``run'' and before the function main() is entered).
5468 At any time after this linking (including when examining core files
5469 from dynamically linked programs), gdb reads the symbols from each
5470 shared library when you type the ``sharedlibrary'' command.
5471 It can be abbreviated ``share''.
5473 sharedlibrary REGEXP: Load shared object library symbols for files
5474 matching a unix regular expression. No argument
5475 indicates to load symbols for all shared libraries.
5477 info sharedlibrary: Status of loaded shared libraries.
5482 A watchpoint stops execution of a program whenever the value of an
5483 expression changes. Checking for this slows down execution
5484 tremendously whenever you are in the scope of the expression, but is
5485 quite useful for catching tough ``bit-spreader'' or pointer misuse
5486 problems. Some machines such as the 386 have hardware for doing this
5487 more quickly, and future versions of gdb will use this hardware.
5489 watch EXP: Set a watchpoint (breakpoint) for an expression.
5491 info watchpoints: Information about your watchpoints.
5493 delete N: Deletes watchpoint number N (same as breakpoints).
5494 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5495 enable N: Re-enables watchpoint number N (same as breakpoints).
5498 * C++ multiple inheritance
5500 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5503 * C++ exception handling
5505 Gdb now supports limited C++ exception handling. Besides the existing
5506 ability to breakpoint on an exception handler, gdb can breakpoint on
5507 the raising of an exception (before the stack is peeled back to the
5510 catch FOO: If there is a FOO exception handler in the dynamic scope,
5511 set a breakpoint to catch exceptions which may be raised there.
5512 Multiple exceptions (``catch foo bar baz'') may be caught.
5514 info catch: Lists all exceptions which may be caught in the
5515 current stack frame.
5518 * Minor command changes
5520 The command ``call func (arg, arg, ...)'' now acts like the print
5521 command, except it does not print or save a value if the function's result
5522 is void. This is similar to dbx usage.
5524 The ``up'' and ``down'' commands now always print the frame they end up
5525 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5526 frames without printing.
5528 * New directory command
5530 'dir' now adds directories to the FRONT of the source search path.
5531 The path starts off empty. Source files that contain debug information
5532 about the directory in which they were compiled can be found even
5533 with an empty path; Sun CC and GCC include this information. If GDB can't
5534 find your source file in the current directory, type "dir .".
5536 * Configuring GDB for compilation
5538 For normal use, type ``./configure host''. See README or gdb.texinfo
5541 GDB now handles cross debugging. If you are remotely debugging between
5542 two different machines, type ``./configure host -target=targ''.
5543 Host is the machine where GDB will run; targ is the machine
5544 where the program that you are debugging will run.