1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.6
7 maint set|show per-command
8 maint set|show per-command space
9 maint set|show per-command time
10 maint set|show per-command symtab
11 Enable display of per-command gdb resource usage.
15 set remote trace-status-packet
16 show remote trace-status-packet
17 Set/show the use of remote protocol qTStatus packet.
19 * The command 'tsave' can now support new option '-ctf' to save trace
20 buffer in Common Trace Format.
24 ** The -trace-save MI command can optionally save trace buffer in Common
27 *** Changes in GDB 7.6
29 * Target record has been renamed to record-full.
30 Record/replay is now enabled with the "record full" command.
31 This also affects settings that are associated with full record/replay
32 that have been moved from "set/show record" to "set/show record full":
34 set|show record full insn-number-max
35 set|show record full stop-at-limit
36 set|show record full memory-query
38 * A new record target "record-btrace" has been added. The new target
39 uses hardware support to record the control-flow of a process. It
40 does not support replaying the execution, but it implements the
41 below new commands for investigating the recorded execution log.
42 This new recording method can be enabled using:
46 The "record-btrace" target is only available on Intel Atom processors
47 and requires a Linux kernel 2.6.32 or later.
49 * Two new commands have been added for record/replay to give information
50 about the recorded execution without having to replay the execution.
51 The commands are only supported by "record btrace".
53 record instruction-history prints the execution history at
54 instruction granularity
56 record function-call-history prints the execution history at
59 * New native configurations
61 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
62 FreeBSD/powerpc powerpc*-*-freebsd
63 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
67 ARM AArch64 aarch64*-*-elf
68 ARM AArch64 GNU/Linux aarch64*-*-linux
69 Lynx 178 PowerPC powerpc-*-lynx*178
70 x86_64/Cygwin x86_64-*-cygwin*
71 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
73 * If the configured location of system.gdbinit file (as given by the
74 --with-system-gdbinit option at configure time) is in the
75 data-directory (as specified by --with-gdb-datadir at configure
76 time) or in one of its subdirectories, then GDB will look for the
77 system-wide init file in the directory specified by the
78 --data-directory command-line option.
80 * New command line options:
82 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
83 other initialization files, unlike -nx which disables all of them.
85 * Removed command line options
87 -epoch This was used by the gdb mode in Epoch, an ancient fork of
90 * The 'ptype' and 'whatis' commands now accept an argument to control
93 * 'info proc' now works on some core files.
97 ** Vectors can be created with gdb.Type.vector.
99 ** Python's atexit.register now works in GDB.
101 ** Types can be pretty-printed via a Python API.
103 ** Python 3 is now supported (in addition to Python 2.4 or later)
105 ** New class gdb.Architecture exposes GDB's internal representation
106 of architecture in the Python API.
108 ** New method Frame.architecture returns the gdb.Architecture object
109 corresponding to the frame's architecture.
111 * New Python-based convenience functions:
113 ** $_memeq(buf1, buf2, length)
114 ** $_streq(str1, str2)
116 ** $_regex(str, regex)
118 * The 'cd' command now defaults to using '~' (the home directory) if not
121 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
122 default for GCC since November 2000.
124 * The command 'forward-search' can now be abbreviated as 'fo'.
126 * The command 'info tracepoints' can now display 'installed on target'
127 or 'not installed on target' for each non-pending location of tracepoint.
129 * New configure options
131 --enable-libmcheck/--disable-libmcheck
132 By default, development versions are built with -lmcheck on hosts
133 that support it, in order to help track memory corruption issues.
134 Release versions, on the other hand, are built without -lmcheck
135 by default. The --enable-libmcheck/--disable-libmcheck configure
136 options allow the user to override that default.
138 * New commands (for set/show, see "New options" below)
141 Catch signals. This is similar to "handle", but allows commands and
142 conditions to be attached.
145 List the BFDs known to GDB.
147 python-interactive [command]
149 Start a Python interactive prompt, or evaluate the optional command
150 and print the result of expressions.
153 "py" is a new alias for "python".
155 enable type-printer [name]...
156 disable type-printer [name]...
157 Enable or disable type printers.
161 ** For the Renesas Super-H architecture, the "regs" command has been removed
162 (has been deprecated in GDB 7.5), and "info all-registers" should be used
167 set print type methods (on|off)
168 show print type methods
169 Control whether method declarations are displayed by "ptype".
170 The default is to show them.
172 set print type typedefs (on|off)
173 show print type typedefs
174 Control whether typedef definitions are displayed by "ptype".
175 The default is to show them.
177 set filename-display basename|relative|absolute
178 show filename-display
179 Control the way in which filenames is displayed.
180 The default is "relative", which preserves previous behavior.
182 set trace-buffer-size
183 show trace-buffer-size
184 Request target to change the size of trace buffer.
186 set remote trace-buffer-size-packet auto|on|off
187 show remote trace-buffer-size-packet
188 Control the use of the remote protocol `QTBuffer:size' packet.
192 Control display of debugging messages related to ARM AArch64.
195 set debug coff-pe-read
196 show debug coff-pe-read
197 Control display of debugging messages related to reading of COFF/PE
202 Control display of debugging messages related to Mach-O symbols
205 set debug notification
206 show debug notification
207 Control display of debugging info for async remote notification.
211 ** Command parameter changes are now notified using new async record
212 "=cmd-param-changed".
213 ** Trace frame changes caused by command "tfind" are now notified using
214 new async record "=traceframe-changed".
215 ** The creation, deletion and modification of trace state variables
216 are now notified using new async records "=tsv-created",
217 "=tsv-deleted" and "=tsv-modified".
218 ** The start and stop of process record are now notified using new
219 async record "=record-started" and "=record-stopped".
220 ** Memory changes are now notified using new async record
222 ** The data-disassemble command response will include a "fullname" field
223 containing the absolute file name when GDB can determine it and source
225 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
226 command, to allow pattern filling of memory areas.
227 ** New commands "-catch-load"/"-catch-unload" added for intercepting
228 library load/unload events.
229 ** The response to breakpoint commands and breakpoint async records
230 includes an "installed" field containing a boolean state about each
231 non-pending tracepoint location is whether installed on target or not.
232 ** Output of the "-trace-status" command includes a "trace-file" field
233 containing the name of the trace file being examined. This field is
234 optional, and only present when examining a trace file.
236 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
237 You must have the LZMA library available when configuring GDB for this
238 feature to be enabled. For more information, see:
239 http://fedoraproject.org/wiki/Features/MiniDebugInfo
244 Set the size of trace buffer. The remote stub reports support for this
245 packet to gdb's qSupported query.
247 *** Changes in GDB 7.5
249 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
250 for more x32 ABI info.
252 * GDB now supports access to MIPS DSP registers on Linux targets.
254 * GDB now supports debugging microMIPS binaries.
256 * The "info os" command on GNU/Linux can now display information on
257 several new classes of objects managed by the operating system:
258 "info os procgroups" lists process groups
259 "info os files" lists file descriptors
260 "info os sockets" lists internet-domain sockets
261 "info os shm" lists shared-memory regions
262 "info os semaphores" lists semaphores
263 "info os msg" lists message queues
264 "info os modules" lists loaded kernel modules
266 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
267 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
268 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
269 options and inspect the probe arguments using the new $_probe_arg family
270 of convenience variables. You can obtain more information about SystemTap
271 in <http://sourceware.org/systemtap/>.
273 * GDB now supports reversible debugging on ARM, it allows you to
274 debug basic ARM and THUMB instructions, and provides
275 record/replay support.
277 * The option "symbol-reloading" has been deleted as it is no longer used.
281 ** GDB commands implemented in Python can now be put in command class
284 ** The "maint set python print-stack on|off" is now deleted.
286 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
287 apply "flag enum"-style pretty-printing to any enum.
289 ** gdb.lookup_symbol can now work when there is no current frame.
291 ** gdb.Symbol now has a 'line' attribute, holding the line number in
292 the source at which the symbol was defined.
294 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
295 method 'value'. The former indicates whether the symbol needs a
296 frame in order to compute its value, and the latter computes the
299 ** A new method 'referenced_value' on gdb.Value objects which can
300 dereference pointer as well as C++ reference values.
302 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
303 which return the global and static blocks (as gdb.Block objects),
304 of the underlying symbol table, respectively.
306 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
307 object associated with a PC value.
309 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
310 of the address range occupied by code for the current source line.
312 * Go language support.
313 GDB now supports debugging programs written in the Go programming
316 * GDBserver now supports stdio connections.
317 E.g. (gdb) target remote | ssh myhost gdbserver - hello
319 * The binary "gdbtui" can no longer be built or installed.
320 Use "gdb -tui" instead.
322 * GDB will now print "flag" enums specially. A flag enum is one where
323 all the enumerator values have no bits in common when pairwise
324 "and"ed. When printing a value whose type is a flag enum, GDB will
325 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
326 (gdb) print (enum E) 3
329 * The filename part of a linespec will now match trailing components
330 of a source file name. For example, "break gcc/expr.c:1000" will
331 now set a breakpoint in build/gcc/expr.c, but not
334 * The "info proc" and "generate-core-file" commands will now also
335 work on remote targets connected to GDBserver on Linux.
337 * The command "info catch" has been removed. It has been disabled
340 * The "catch exception" and "catch assert" commands now accept
341 a condition at the end of the command, much like the "break"
342 command does. For instance:
344 (gdb) catch exception Constraint_Error if Barrier = True
346 Previously, it was possible to add a condition to such catchpoints,
347 but it had to be done as a second step, after the catchpoint had been
348 created, using the "condition" command.
350 * The "info static-tracepoint-marker" command will now also work on
351 native Linux targets with in-process agent.
353 * GDB can now set breakpoints on inlined functions.
355 * The .gdb_index section has been updated to include symbols for
356 inlined functions. GDB will ignore older .gdb_index sections by
357 default, which could cause symbol files to be loaded more slowly
358 until their .gdb_index sections can be recreated. The new command
359 "set use-deprecated-index-sections on" will cause GDB to use any older
360 .gdb_index sections it finds. This will restore performance, but the
361 ability to set breakpoints on inlined functions will be lost in symbol
362 files with older .gdb_index sections.
364 The .gdb_index section has also been updated to record more information
365 about each symbol. This speeds up the "info variables", "info functions"
366 and "info types" commands when used with programs having the .gdb_index
367 section, as well as speeding up debugging with shared libraries using
368 the .gdb_index section.
370 * Ada support for GDB/MI Variable Objects has been added.
372 * GDB can now support 'breakpoint always-inserted mode' in 'record'
377 ** New command -info-os is the MI equivalent of "info os".
379 ** Output logs ("set logging" and related) now include MI output.
383 ** "set use-deprecated-index-sections on|off"
384 "show use-deprecated-index-sections on|off"
385 Controls the use of deprecated .gdb_index sections.
387 ** "catch load" and "catch unload" can be used to stop when a shared
388 library is loaded or unloaded, respectively.
390 ** "enable count" can be used to auto-disable a breakpoint after
393 ** "info vtbl" can be used to show the virtual method tables for
394 C++ and Java objects.
396 ** "explore" and its sub commands "explore value" and "explore type"
397 can be used to reccursively explore values and types of
398 expressions. These commands are available only if GDB is
399 configured with '--with-python'.
401 ** "info auto-load" shows status of all kinds of auto-loaded files,
402 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
403 sequences of commands files, "info auto-load python-scripts"
404 shows status of auto-loading Python script files,
405 "info auto-load local-gdbinit" shows status of loading init file
406 (.gdbinit) from current directory and "info auto-load libthread-db" shows
407 status of inferior specific thread debugging shared library loading.
409 ** "info auto-load-scripts", "set auto-load-scripts on|off"
410 and "show auto-load-scripts" commands have been deprecated, use their
411 "info auto-load python-scripts", "set auto-load python-scripts on|off"
412 and "show auto-load python-scripts" counterparts instead.
414 ** "dprintf location,format,args..." creates a dynamic printf, which
415 is basically a breakpoint that does a printf and immediately
416 resumes your program's execution, so it is like a printf that you
417 can insert dynamically at runtime instead of at compiletime.
419 ** "set print symbol"
421 Controls whether GDB attempts to display the symbol, if any,
422 corresponding to addresses it prints. This defaults to "on", but
423 you can set it to "off" to restore GDB's previous behavior.
425 * Deprecated commands
427 ** For the Renesas Super-H architecture, the "regs" command has been
428 deprecated, and "info all-registers" should be used instead.
432 Renesas RL78 rl78-*-elf
433 HP OpenVMS ia64 ia64-hp-openvms*
435 * GDBserver supports evaluation of breakpoint conditions. When
436 support is advertised by GDBserver, GDB may be told to send the
437 breakpoint conditions in bytecode form to GDBserver. GDBserver
438 will only report the breakpoint trigger to GDB when its condition
444 show mips compression
445 Select the compressed ISA encoding used in functions that have no symbol
446 information available. The encoding can be set to either of:
449 and is updated automatically from ELF file flags if available.
451 set breakpoint condition-evaluation
452 show breakpoint condition-evaluation
453 Control whether breakpoint conditions are evaluated by GDB ("host") or by
454 GDBserver ("target"). Default option "auto" chooses the most efficient
456 This option can improve debugger efficiency depending on the speed of the
460 Disable auto-loading globally.
463 Show auto-loading setting of all kinds of auto-loaded files.
465 set auto-load gdb-scripts on|off
466 show auto-load gdb-scripts
467 Control auto-loading of GDB canned sequences of commands files.
469 set auto-load python-scripts on|off
470 show auto-load python-scripts
471 Control auto-loading of Python script files.
473 set auto-load local-gdbinit on|off
474 show auto-load local-gdbinit
475 Control loading of init file (.gdbinit) from current directory.
477 set auto-load libthread-db on|off
478 show auto-load libthread-db
479 Control auto-loading of inferior specific thread debugging shared library.
481 set auto-load scripts-directory <dir1>[:<dir2>...]
482 show auto-load scripts-directory
483 Set a list of directories from which to load auto-loaded scripts.
484 Automatically loaded Python scripts and GDB scripts are located in one
485 of the directories listed by this option.
486 The delimiter (':' above) may differ according to the host platform.
488 set auto-load safe-path <dir1>[:<dir2>...]
489 show auto-load safe-path
490 Set a list of directories from which it is safe to auto-load files.
491 The delimiter (':' above) may differ according to the host platform.
493 set debug auto-load on|off
495 Control display of debugging info for auto-loading the files above.
497 set dprintf-style gdb|call|agent
499 Control the way in which a dynamic printf is performed; "gdb"
500 requests a GDB printf command, while "call" causes dprintf to call a
501 function in the inferior. "agent" requests that the target agent
502 (such as GDBserver) do the printing.
504 set dprintf-function <expr>
505 show dprintf-function
506 set dprintf-channel <expr>
508 Set the function and optional first argument to the call when using
509 the "call" style of dynamic printf.
511 set disconnected-dprintf on|off
512 show disconnected-dprintf
513 Control whether agent-style dynamic printfs continue to be in effect
514 after GDB disconnects.
516 * New configure options
519 Configure default value for the 'set auto-load scripts-directory'
520 setting above. It defaults to '$debugdir:$datadir/auto-load',
521 $debugdir representing global debugging info directories (available
522 via 'show debug-file-directory') and $datadir representing GDB's data
523 directory (available via 'show data-directory').
525 --with-auto-load-safe-path
526 Configure default value for the 'set auto-load safe-path' setting
527 above. It defaults to the --with-auto-load-dir setting.
529 --without-auto-load-safe-path
530 Set 'set auto-load safe-path' to '/', effectively disabling this
535 z0/z1 conditional breakpoints extension
537 The z0/z1 breakpoint insertion packets have been extended to carry
538 a list of conditional expressions over to the remote stub depending on the
539 condition evaluation mode. The use of this extension can be controlled
540 via the "set remote conditional-breakpoints-packet" command.
544 Specify the signals which the remote stub may pass to the debugged
545 program without GDB involvement.
547 * New command line options
549 --init-command=FILE, -ix Like --command, -x but execute it
550 before loading inferior.
551 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
552 execute it before loading inferior.
554 *** Changes in GDB 7.4
556 * GDB now handles ambiguous linespecs more consistently; the existing
557 FILE:LINE support has been expanded to other types of linespecs. A
558 breakpoint will now be set on all matching locations in all
559 inferiors, and locations will be added or removed according to
562 * GDB now allows you to skip uninteresting functions and files when
563 stepping with the "skip function" and "skip file" commands.
565 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
566 and "show remote hardware-watchpoint-length-limit". These allows to
567 set or show the maximum length limit (in bytes) of a remote
568 target hardware watchpoint.
570 This allows e.g. to use "unlimited" hardware watchpoints with the
571 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
572 watchpoints are slower than real hardware watchpoints but are
573 significantly faster than gdb software watchpoints.
577 ** The register_pretty_printer function in module gdb.printing now takes
578 an optional `replace' argument. If True, the new printer replaces any
581 ** The "maint set python print-stack on|off" command has been
582 deprecated and will be deleted in GDB 7.5.
583 A new command: "set python print-stack none|full|message" has
584 replaced it. Additionally, the default for "print-stack" is
585 now "message", which just prints the error message without
588 ** A prompt substitution hook (prompt_hook) is now available to the
591 ** A new Python module, gdb.prompt has been added to the GDB Python
592 modules library. This module provides functionality for
593 escape sequences in prompts (used by set/show
594 extended-prompt). These escape sequences are replaced by their
597 ** Python commands and convenience-functions located in
598 'data-directory'/python/gdb/command and
599 'data-directory'/python/gdb/function are now automatically loaded
602 ** Blocks now provide four new attributes. global_block and
603 static_block will return the global and static blocks
604 respectively. is_static and is_global are boolean attributes
605 that indicate if the block is one of those two types.
607 ** Symbols now provide the "type" attribute, the type of the symbol.
609 ** The "gdb.breakpoint" function has been deprecated in favor of
612 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
613 of a function. This class is based on the "finish" command
614 available in the CLI.
616 ** Type objects for struct and union types now allow access to
617 the fields using standard Python dictionary (mapping) methods.
618 For example, "some_type['myfield']" now works, as does
621 ** A new event "gdb.new_objfile" has been added, triggered by loading a
624 ** A new function, "deep_items" has been added to the gdb.types
625 module in the GDB Python modules library. This function returns
626 an iterator over the fields of a struct or union type. Unlike
627 the standard Python "iteritems" method, it will recursively traverse
628 any anonymous fields.
632 ** "*stopped" events can report several new "reason"s, such as
635 ** Breakpoint changes are now notified using new async records, like
636 "=breakpoint-modified".
638 ** New command -ada-task-info.
640 * libthread-db-search-path now supports two special values: $sdir and $pdir.
641 $sdir specifies the default system locations of shared libraries.
642 $pdir specifies the directory where the libpthread used by the application
645 GDB no longer looks in $sdir and $pdir after it has searched the directories
646 mentioned in libthread-db-search-path. If you want to search those
647 directories, they must be specified in libthread-db-search-path.
648 The default value of libthread-db-search-path on GNU/Linux and Solaris
649 systems is now "$sdir:$pdir".
651 $pdir is not supported by gdbserver, it is currently ignored.
652 $sdir is supported by gdbserver.
654 * New configure option --with-iconv-bin.
655 When using the internationalization support like the one in the GNU C
656 library, GDB will invoke the "iconv" program to get a list of supported
657 character sets. If this program lives in a non-standard location, one can
658 use this option to specify where to find it.
660 * When natively debugging programs on PowerPC BookE processors running
661 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
662 watchpoints, which specify a mask in addition to an address to watch.
663 The mask specifies that some bits of an address (the bits which are
664 reset in the mask) should be ignored when matching the address accessed
665 by the inferior against the watchpoint address. See the "PowerPC Embedded"
666 section in the user manual for more details.
668 * The new option --once causes GDBserver to stop listening for connections once
669 the first connection is made. The listening port used by GDBserver will
670 become available after that.
672 * New commands "info macros" and "alias" have been added.
674 * New function parameters suffix @entry specifies value of function parameter
675 at the time the function got called. Entry values are available only since
681 "!" is now an alias of the "shell" command.
682 Note that no space is needed between "!" and SHELL COMMAND.
686 watch EXPRESSION mask MASK_VALUE
687 The watch command now supports the mask argument which allows creation
688 of masked watchpoints, if the current architecture supports this feature.
690 info auto-load-scripts [REGEXP]
691 This command was formerly named "maintenance print section-scripts".
692 It is now generally useful and is no longer a maintenance-only command.
694 info macro [-all] [--] MACRO
695 The info macro command has new options `-all' and `--'. The first for
696 printing all definitions of a macro. The second for explicitly specifying
697 the end of arguments and the beginning of the macro name in case the macro
698 name starts with a hyphen.
700 collect[/s] EXPRESSIONS
701 The tracepoint collect command now takes an optional modifier "/s"
702 that directs it to dereference pointer-to-character types and
703 collect the bytes of memory up to a zero byte. The behavior is
704 similar to what you see when you use the regular print command on a
705 string. An optional integer following the "/s" sets a bound on the
706 number of bytes that will be collected.
709 The trace start command now interprets any supplied arguments as a
710 note to be recorded with the trace run, with an effect similar to
711 setting the variable trace-notes.
714 The trace stop command now interprets any arguments as a note to be
715 mentioned along with the tstatus report that the trace was stopped
716 with a command. The effect is similar to setting the variable
719 * Tracepoints can now be enabled and disabled at any time after a trace
720 experiment has been started using the standard "enable" and "disable"
721 commands. It is now possible to start a trace experiment with no enabled
722 tracepoints; GDB will display a warning, but will allow the experiment to
723 begin, assuming that tracepoints will be enabled as needed while the trace
726 * Fast tracepoints on 32-bit x86-architectures can now be placed at
727 locations with 4-byte instructions, when they were previously
728 limited to locations with instructions of 5 bytes or longer.
732 set debug dwarf2-read
733 show debug dwarf2-read
734 Turns on or off display of debugging messages related to reading
735 DWARF debug info. The default is off.
737 set debug symtab-create
738 show debug symtab-create
739 Turns on or off display of debugging messages related to symbol table
740 creation. The default is off.
744 Set the GDB prompt, and allow escape sequences to be inserted to
745 display miscellaneous information (see 'help set extended-prompt'
746 for the list of sequences). This prompt (and any information
747 accessed through the escape sequences) is updated every time the
750 set print entry-values (both|compact|default|if-needed|no|only|preferred)
751 show print entry-values
752 Set printing of frame argument values at function entry. In some cases
753 GDB can determine the value of function argument which was passed by the
754 function caller, even if the value was modified inside the called function.
756 set debug entry-values
757 show debug entry-values
758 Control display of debugging info for determining frame argument values at
759 function entry and virtual tail call frames.
761 set basenames-may-differ
762 show basenames-may-differ
763 Set whether a source file may have multiple base names.
764 (A "base name" is the name of a file with the directory part removed.
765 Example: The base name of "/home/user/hello.c" is "hello.c".)
766 If set, GDB will canonicalize file names (e.g., expand symlinks)
767 before comparing them. Canonicalization is an expensive operation,
768 but it allows the same file be known by more than one base name.
769 If not set (the default), all source files are assumed to have just
770 one base name, and gdb will do file name comparisons more efficiently.
776 Set a user name and notes for the current and any future trace runs.
777 This is useful for long-running and/or disconnected traces, to
778 inform others (or yourself) as to who is running the trace, supply
779 contact information, or otherwise explain what is going on.
782 show trace-stop-notes
783 Set a note attached to the trace run, that is displayed when the
784 trace has been stopped by a tstop command. This is useful for
785 instance as an explanation, if you are stopping a trace run that was
786 started by someone else.
792 Dynamically enable a tracepoint in a started trace experiment.
796 Dynamically disable a tracepoint in a started trace experiment.
800 Set the user and notes of the trace run.
804 Query the current status of a tracepoint.
808 Query the minimum length of instruction at which a fast tracepoint may
811 * Dcache size (number of lines) and line-size are now runtime-configurable
812 via "set dcache line" and "set dcache line-size" commands.
816 Texas Instruments TMS320C6x tic6x-*-*
820 Renesas RL78 rl78-*-elf
822 *** Changes in GDB 7.3.1
824 * The build failure for NetBSD and OpenBSD targets have now been fixed.
826 *** Changes in GDB 7.3
828 * GDB has a new command: "thread find [REGEXP]".
829 It finds the thread id whose name, target id, or thread extra info
830 matches the given regular expression.
832 * The "catch syscall" command now works on mips*-linux* targets.
834 * The -data-disassemble MI command now supports modes 2 and 3 for
835 dumping the instruction opcodes.
837 * New command line options
839 -data-directory DIR Specify DIR as the "data-directory".
840 This is mostly for testing purposes.
842 * The "maint set python auto-load on|off" command has been renamed to
843 "set auto-load-scripts on|off".
845 * GDB has a new command: "set directories".
846 It is like the "dir" command except that it replaces the
847 source path list instead of augmenting it.
849 * GDB now understands thread names.
851 On GNU/Linux, "info threads" will display the thread name as set by
852 prctl or pthread_setname_np.
854 There is also a new command, "thread name", which can be used to
855 assign a name internally for GDB to display.
858 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
859 has been integrated into GDB.
863 ** The function gdb.Write now accepts an optional keyword 'stream'.
864 This keyword, when provided, will direct the output to either
865 stdout, stderr, or GDB's logging output.
867 ** Parameters can now be be sub-classed in Python, and in particular
868 you may implement the get_set_doc and get_show_doc functions.
869 This improves how Parameter set/show documentation is processed
870 and allows for more dynamic content.
872 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
873 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
874 have an is_valid method.
876 ** Breakpoints can now be sub-classed in Python, and in particular
877 you may implement a 'stop' function that is executed each time
878 the inferior reaches that breakpoint.
880 ** New function gdb.lookup_global_symbol looks up a global symbol.
882 ** GDB values in Python are now callable if the value represents a
883 function. For example, if 'some_value' represents a function that
884 takes two integer parameters and returns a value, you can call
885 that function like so:
887 result = some_value (10,20)
889 ** Module gdb.types has been added.
890 It contains a collection of utilities for working with gdb.Types objects:
891 get_basic_type, has_field, make_enum_dict.
893 ** Module gdb.printing has been added.
894 It contains utilities for writing and registering pretty-printers.
895 New classes: PrettyPrinter, SubPrettyPrinter,
896 RegexpCollectionPrettyPrinter.
897 New function: register_pretty_printer.
899 ** New commands "info pretty-printers", "enable pretty-printer" and
900 "disable pretty-printer" have been added.
902 ** gdb.parameter("directories") is now available.
904 ** New function gdb.newest_frame returns the newest frame in the
907 ** The gdb.InferiorThread class has a new "name" attribute. This
908 holds the thread's name.
910 ** Python Support for Inferior events.
911 Python scripts can add observers to be notified of events
912 occurring in the process being debugged.
913 The following events are currently supported:
914 - gdb.events.cont Continue event.
915 - gdb.events.exited Inferior exited event.
916 - gdb.events.stop Signal received, and Breakpoint hit events.
920 ** GDB now puts template parameters in scope when debugging in an
921 instantiation. For example, if you have:
923 template<int X> int func (void) { return X; }
925 then if you step into func<5>, "print X" will show "5". This
926 feature requires proper debuginfo support from the compiler; it
927 was added to GCC 4.5.
929 ** The motion commands "next", "finish", "until", and "advance" now
930 work better when exceptions are thrown. In particular, GDB will
931 no longer lose control of the inferior; instead, the GDB will
932 stop the inferior at the point at which the exception is caught.
933 This functionality requires a change in the exception handling
934 code that was introduced in GCC 4.5.
936 * GDB now follows GCC's rules on accessing volatile objects when
937 reading or writing target state during expression evaluation.
938 One notable difference to prior behavior is that "print x = 0"
939 no longer generates a read of x; the value of the assignment is
940 now always taken directly from the value being assigned.
942 * GDB now has some support for using labels in the program's source in
943 linespecs. For instance, you can use "advance label" to continue
944 execution to a label.
946 * GDB now has support for reading and writing a new .gdb_index
947 section. This section holds a fast index of DWARF debugging
948 information and can be used to greatly speed up GDB startup and
949 operation. See the documentation for `save gdb-index' for details.
951 * The "watch" command now accepts an optional "-location" argument.
952 When used, this causes GDB to watch the memory referred to by the
953 expression. Such a watchpoint is never deleted due to it going out
956 * GDB now supports thread debugging of core dumps on GNU/Linux.
958 GDB now activates thread debugging using the libthread_db library
959 when debugging GNU/Linux core dumps, similarly to when debugging
960 live processes. As a result, when debugging a core dump file, GDB
961 is now able to display pthread_t ids of threads. For example, "info
962 threads" shows the same output as when debugging the process when it
963 was live. In earlier releases, you'd see something like this:
966 * 1 LWP 6780 main () at main.c:10
968 While now you see this:
971 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
973 It is also now possible to inspect TLS variables when debugging core
976 When debugging a core dump generated on a machine other than the one
977 used to run GDB, you may need to point GDB at the correct
978 libthread_db library with the "set libthread-db-search-path"
979 command. See the user manual for more details on this command.
981 * When natively debugging programs on PowerPC BookE processors running
982 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
983 which stop execution of the inferior whenever it executes an instruction
984 at any address within the specified range. See the "PowerPC Embedded"
985 section in the user manual for more details.
987 * New features in the GDB remote stub, GDBserver
989 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
990 and i686 LynxOS (version 5.x).
992 ** GDBserver is now supported on Blackfin Linux.
994 * New native configurations
996 ia64 HP-UX ia64-*-hpux*
1000 Analog Devices, Inc. Blackfin Processor bfin-*
1002 * Ada task switching is now supported on sparc-elf targets when
1003 debugging a program using the Ravenscar Profile. For more information,
1004 see the "Tasking Support when using the Ravenscar Profile" section
1005 in the GDB user manual.
1007 * Guile support was removed.
1009 * New features in the GNU simulator
1011 ** The --map-info flag lists all known core mappings.
1013 ** CFI flashes may be simulated via the "cfi" device.
1015 *** Changes in GDB 7.2
1017 * Shared library support for remote targets by default
1019 When GDB is configured for a generic, non-OS specific target, like
1020 for example, --target=arm-eabi or one of the many *-*-elf targets,
1021 GDB now queries remote stubs for loaded shared libraries using the
1022 `qXfer:libraries:read' packet. Previously, shared library support
1023 was always disabled for such configurations.
1027 ** Argument Dependent Lookup (ADL)
1029 In C++ ADL lookup directs function search to the namespaces of its
1030 arguments even if the namespace has not been imported.
1040 Here the compiler will search for `foo' in the namespace of 'b'
1041 and find A::foo. GDB now supports this. This construct is commonly
1042 used in the Standard Template Library for operators.
1044 ** Improved User Defined Operator Support
1046 In addition to member operators, GDB now supports lookup of operators
1047 defined in a namespace and imported with a `using' directive, operators
1048 defined in the global scope, operators imported implicitly from an
1049 anonymous namespace, and the ADL operators mentioned in the previous
1051 GDB now also supports proper overload resolution for all the previously
1052 mentioned flavors of operators.
1054 ** static const class members
1056 Printing of static const class members that are initialized in the
1057 class definition has been fixed.
1059 * Windows Thread Information Block access.
1061 On Windows targets, GDB now supports displaying the Windows Thread
1062 Information Block (TIB) structure. This structure is visible either
1063 by using the new command `info w32 thread-information-block' or, by
1064 dereferencing the new convenience variable named `$_tlb', a
1065 thread-specific pointer to the TIB. This feature is also supported
1066 when remote debugging using GDBserver.
1068 * Static tracepoints
1070 Static tracepoints are calls in the user program into a tracing
1071 library. One such library is a port of the LTTng kernel tracer to
1072 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1073 When debugging with GDBserver, GDB now supports combining the GDB
1074 tracepoint machinery with such libraries. For example: the user can
1075 use GDB to probe a static tracepoint marker (a call from the user
1076 program into the tracing library) with the new "strace" command (see
1077 "New commands" below). This creates a "static tracepoint" in the
1078 breakpoint list, that can be manipulated with the same feature set
1079 as fast and regular tracepoints. E.g., collect registers, local and
1080 global variables, collect trace state variables, and define
1081 tracepoint conditions. In addition, the user can collect extra
1082 static tracepoint marker specific data, by collecting the new
1083 $_sdata internal variable. When analyzing the trace buffer, you can
1084 inspect $_sdata like any other variable available to GDB. For more
1085 information, see the "Tracepoints" chapter in GDB user manual. New
1086 remote packets have been defined to support static tracepoints, see
1087 the "New remote packets" section below.
1089 * Better reconstruction of tracepoints after disconnected tracing
1091 GDB will attempt to download the original source form of tracepoint
1092 definitions when starting a trace run, and then will upload these
1093 upon reconnection to the target, resulting in a more accurate
1094 reconstruction of the tracepoints that are in use on the target.
1098 You can now exercise direct control over the ways that GDB can
1099 affect your program. For instance, you can disallow the setting of
1100 breakpoints, so that the program can run continuously (assuming
1101 non-stop mode). In addition, the "observer" variable is available
1102 to switch all of the different controls; in observer mode, GDB
1103 cannot affect the target's behavior at all, which is useful for
1104 tasks like diagnosing live systems in the field.
1106 * The new convenience variable $_thread holds the number of the
1109 * New remote packets
1113 Return the address of the Windows Thread Information Block of a given thread.
1117 In response to several of the tracepoint packets, the target may now
1118 also respond with a number of intermediate `qRelocInsn' request
1119 packets before the final result packet, to have GDB handle
1120 relocating an instruction to execute at a different address. This
1121 is particularly useful for stubs that support fast tracepoints. GDB
1122 reports support for this feature in the qSupported packet.
1126 List static tracepoint markers in the target program.
1130 List static tracepoint markers at a given address in the target
1133 qXfer:statictrace:read
1135 Read the static trace data collected (by a `collect $_sdata'
1136 tracepoint action). The remote stub reports support for this packet
1137 to gdb's qSupported query.
1141 Send the current settings of GDB's permission flags.
1145 Send part of the source (textual) form of a tracepoint definition,
1146 which includes location, conditional, and action list.
1148 * The source command now accepts a -s option to force searching for the
1149 script in the source search path even if the script name specifies
1152 * New features in the GDB remote stub, GDBserver
1154 - GDBserver now support tracepoints (including fast tracepoints, and
1155 static tracepoints). The feature is currently supported by the
1156 i386-linux and amd64-linux builds. See the "Tracepoints support
1157 in gdbserver" section in the manual for more information.
1159 GDBserver JIT compiles the tracepoint's conditional agent
1160 expression bytecode into native code whenever possible for low
1161 overhead dynamic tracepoints conditionals. For such tracepoints,
1162 an expression that examines program state is evaluated when the
1163 tracepoint is reached, in order to determine whether to capture
1164 trace data. If the condition is simple and false, processing the
1165 tracepoint finishes very quickly and no data is gathered.
1167 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1168 for static tracepoints support.
1170 - GDBserver now supports x86_64 Windows 64-bit debugging.
1172 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1173 it understands register description.
1175 * The --batch flag now disables pagination and queries.
1177 * X86 general purpose registers
1179 GDB now supports reading/writing byte, word and double-word x86
1180 general purpose registers directly. This means you can use, say,
1181 $ah or $ax to refer, respectively, to the byte register AH and
1182 16-bit word register AX that are actually portions of the 32-bit
1183 register EAX or 64-bit register RAX.
1185 * The `commands' command now accepts a range of breakpoints to modify.
1186 A plain `commands' following a command that creates multiple
1187 breakpoints affects all the breakpoints set by that command. This
1188 applies to breakpoints set by `rbreak', and also applies when a
1189 single `break' command creates multiple breakpoints (e.g.,
1190 breakpoints on overloaded c++ functions).
1192 * The `rbreak' command now accepts a filename specification as part of
1193 its argument, limiting the functions selected by the regex to those
1194 in the specified file.
1196 * Support for remote debugging Windows and SymbianOS shared libraries
1197 from Unix hosts has been improved. Non Windows GDB builds now can
1198 understand target reported file names that follow MS-DOS based file
1199 system semantics, such as file names that include drive letters and
1200 use the backslash character as directory separator. This makes it
1201 possible to transparently use the "set sysroot" and "set
1202 solib-search-path" on Unix hosts to point as host copies of the
1203 target's shared libraries. See the new command "set
1204 target-file-system-kind" described below, and the "Commands to
1205 specify files" section in the user manual for more information.
1209 eval template, expressions...
1210 Convert the values of one or more expressions under the control
1211 of the string template to a command line, and call it.
1213 set target-file-system-kind unix|dos-based|auto
1214 show target-file-system-kind
1215 Set or show the assumed file system kind for target reported file
1218 save breakpoints <filename>
1219 Save all current breakpoint definitions to a file suitable for use
1220 in a later debugging session. To read the saved breakpoint
1221 definitions, use the `source' command.
1223 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1226 info static-tracepoint-markers
1227 Display information about static tracepoint markers in the target.
1229 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1230 Define a static tracepoint by probing a marker at the given
1231 function, line, address, or marker ID.
1235 Enable and disable observer mode.
1237 set may-write-registers on|off
1238 set may-write-memory on|off
1239 set may-insert-breakpoints on|off
1240 set may-insert-tracepoints on|off
1241 set may-insert-fast-tracepoints on|off
1242 set may-interrupt on|off
1243 Set individual permissions for GDB effects on the target. Note that
1244 some of these settings can have undesirable or surprising
1245 consequences, particularly when changed in the middle of a session.
1246 For instance, disabling the writing of memory can prevent
1247 breakpoints from being inserted, cause single-stepping to fail, or
1248 even crash your program, if you disable after breakpoints have been
1249 inserted. However, GDB should not crash.
1251 set record memory-query on|off
1252 show record memory-query
1253 Control whether to stop the inferior if memory changes caused
1254 by an instruction cannot be recorded.
1259 The disassemble command now supports "start,+length" form of two arguments.
1263 ** GDB now provides a new directory location, called the python directory,
1264 where Python scripts written for GDB can be installed. The location
1265 of that directory is <data-directory>/python, where <data-directory>
1266 is the GDB data directory. For more details, see section `Scripting
1267 GDB using Python' in the manual.
1269 ** The GDB Python API now has access to breakpoints, symbols, symbol
1270 tables, program spaces, inferiors, threads and frame's code blocks.
1271 Additionally, GDB Parameters can now be created from the API, and
1272 manipulated via set/show in the CLI.
1274 ** New functions gdb.target_charset, gdb.target_wide_charset,
1275 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1277 ** New exception gdb.GdbError.
1279 ** Pretty-printers are now also looked up in the current program space.
1281 ** Pretty-printers can now be individually enabled and disabled.
1283 ** GDB now looks for names of Python scripts to auto-load in a
1284 special section named `.debug_gdb_scripts', in addition to looking
1285 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1287 * Tracepoint actions were unified with breakpoint commands. In particular,
1288 there are no longer differences in "info break" output for breakpoints and
1289 tracepoints and the "commands" command can be used for both tracepoints and
1290 regular breakpoints.
1294 ARM Symbian arm*-*-symbianelf*
1296 * D language support.
1297 GDB now supports debugging programs written in the D programming
1300 * GDB now supports the extended ptrace interface for PowerPC which is
1301 available since Linux kernel version 2.6.34. This automatically enables
1302 any hardware breakpoints and additional hardware watchpoints available in
1303 the processor. The old ptrace interface exposes just one hardware
1304 watchpoint and no hardware breakpoints.
1306 * GDB is now able to use the Data Value Compare (DVC) register available on
1307 embedded PowerPC processors to implement in hardware simple watchpoint
1308 conditions of the form:
1310 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1312 This works in native GDB running on Linux kernels with the extended ptrace
1313 interface mentioned above.
1315 *** Changes in GDB 7.1
1319 ** Namespace Support
1321 GDB now supports importing of namespaces in C++. This enables the
1322 user to inspect variables from imported namespaces. Support for
1323 namepace aliasing has also been added. So, if a namespace is
1324 aliased in the current scope (e.g. namepace C=A; ) the user can
1325 print variables using the alias (e.g. (gdb) print C::x).
1329 All known bugs relating to the printing of virtual base class were
1330 fixed. It is now possible to call overloaded static methods using a
1335 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1336 and reinterpret_cast<> are now handled by the C++ expression parser.
1340 Xilinx MicroBlaze microblaze-*-*
1345 Xilinx MicroBlaze microblaze
1348 * Multi-program debugging.
1350 GDB now has support for multi-program (a.k.a. multi-executable or
1351 multi-exec) debugging. This allows for debugging multiple inferiors
1352 simultaneously each running a different program under the same GDB
1353 session. See "Debugging Multiple Inferiors and Programs" in the
1354 manual for more information. This implied some user visible changes
1355 in the multi-inferior support. For example, "info inferiors" now
1356 lists inferiors that are not running yet or that have exited
1357 already. See also "New commands" and "New options" below.
1359 * New tracing features
1361 GDB's tracepoint facility now includes several new features:
1363 ** Trace state variables
1365 GDB tracepoints now include support for trace state variables, which
1366 are variables managed by the target agent during a tracing
1367 experiment. They are useful for tracepoints that trigger each
1368 other, so for instance one tracepoint can count hits in a variable,
1369 and then a second tracepoint has a condition that is true when the
1370 count reaches a particular value. Trace state variables share the
1371 $-syntax of GDB convenience variables, and can appear in both
1372 tracepoint actions and condition expressions. Use the "tvariable"
1373 command to create, and "info tvariables" to view; see "Trace State
1374 Variables" in the manual for more detail.
1378 GDB now includes an option for defining fast tracepoints, which
1379 targets may implement more efficiently, such as by installing a jump
1380 into the target agent rather than a trap instruction. The resulting
1381 speedup can be by two orders of magnitude or more, although the
1382 tradeoff is that some program locations on some target architectures
1383 might not allow fast tracepoint installation, for instance if the
1384 instruction to be replaced is shorter than the jump. To request a
1385 fast tracepoint, use the "ftrace" command, with syntax identical to
1386 the regular trace command.
1388 ** Disconnected tracing
1390 It is now possible to detach GDB from the target while it is running
1391 a trace experiment, then reconnect later to see how the experiment
1392 is going. In addition, a new variable disconnected-tracing lets you
1393 tell the target agent whether to continue running a trace if the
1394 connection is lost unexpectedly.
1398 GDB now has the ability to save the trace buffer into a file, and
1399 then use that file as a target, similarly to you can do with
1400 corefiles. You can select trace frames, print data that was
1401 collected in them, and use tstatus to display the state of the
1402 tracing run at the moment that it was saved. To create a trace
1403 file, use "tsave <filename>", and to use it, do "target tfile
1406 ** Circular trace buffer
1408 You can ask the target agent to handle the trace buffer as a
1409 circular buffer, discarding the oldest trace frames to make room for
1410 newer ones, by setting circular-trace-buffer to on. This feature may
1411 not be available for all target agents.
1416 The disassemble command, when invoked with two arguments, now requires
1417 the arguments to be comma-separated.
1420 The info variables command now displays variable definitions. Files
1421 which only declare a variable are not shown.
1424 The source command is now capable of sourcing Python scripts.
1425 This feature is dependent on the debugger being build with Python
1428 Related to this enhancement is also the introduction of a new command
1429 "set script-extension" (see below).
1431 * New commands (for set/show, see "New options" below)
1433 record save [<FILENAME>]
1434 Save a file (in core file format) containing the process record
1435 execution log for replay debugging at a later time.
1437 record restore <FILENAME>
1438 Restore the process record execution log that was saved at an
1439 earlier time, for replay debugging.
1441 add-inferior [-copies <N>] [-exec <FILENAME>]
1444 clone-inferior [-copies <N>] [ID]
1445 Make a new inferior ready to execute the same program another
1446 inferior has loaded.
1451 maint info program-spaces
1452 List the program spaces loaded into GDB.
1454 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1455 show remote interrupt-sequence
1456 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1457 as the sequence to the remote target in order to interrupt the execution.
1458 Ctrl-C is a default. Some system prefers BREAK which is high level of
1459 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1460 Magic SysRq g. It is BREAK signal and character 'g'.
1462 set remote interrupt-on-connect [on | off]
1463 show remote interrupt-on-connect
1464 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1465 remote target when gdb connects to it. This is needed when you debug
1468 set remotebreak [on | off]
1470 Deprecated. Use "set/show remote interrupt-sequence" instead.
1472 tvariable $NAME [ = EXP ]
1473 Create or modify a trace state variable.
1476 List trace state variables and their values.
1478 delete tvariable $NAME ...
1479 Delete one or more trace state variables.
1482 Evaluate the given expressions without collecting anything into the
1483 trace buffer. (Valid in tracepoint actions only.)
1485 ftrace FN / FILE:LINE / *ADDR
1486 Define a fast tracepoint at the given function, line, or address.
1488 * New expression syntax
1490 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1491 GDB now parses 0b101010 identically with 42.
1495 set follow-exec-mode new|same
1496 show follow-exec-mode
1497 Control whether GDB reuses the same inferior across an exec call or
1498 creates a new one. This is useful to be able to restart the old
1499 executable after the inferior having done an exec call.
1501 set default-collect EXPR, ...
1502 show default-collect
1503 Define a list of expressions to be collected at each tracepoint.
1504 This is a useful way to ensure essential items are not overlooked,
1505 such as registers or a critical global variable.
1507 set disconnected-tracing
1508 show disconnected-tracing
1509 If set to 1, the target is instructed to continue tracing if it
1510 loses its connection to GDB. If 0, the target is to stop tracing
1513 set circular-trace-buffer
1514 show circular-trace-buffer
1515 If set to on, the target is instructed to use a circular trace buffer
1516 and discard the oldest trace frames instead of stopping the trace due
1517 to a full trace buffer. If set to off, the trace stops when the buffer
1518 fills up. Some targets may not support this.
1520 set script-extension off|soft|strict
1521 show script-extension
1522 If set to "off", the debugger does not perform any script language
1523 recognition, and all sourced files are assumed to be GDB scripts.
1524 If set to "soft" (the default), files are sourced according to
1525 filename extension, falling back to GDB scripts if the first
1527 If set to "strict", files are sourced according to filename extension.
1529 set ada trust-PAD-over-XVS on|off
1530 show ada trust-PAD-over-XVS
1531 If off, activate a workaround against a bug in the debugging information
1532 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1533 the GCC sources for more information about the GNAT encoding and
1534 PAD types in particular). It is always safe to set this option to
1535 off, but this introduces a slight performance penalty. The default
1538 * Python API Improvements
1540 ** GDB provides the new class gdb.LazyString. This is useful in
1541 some pretty-printing cases. The new method gdb.Value.lazy_string
1542 provides a simple way to create objects of this type.
1544 ** The fields returned by gdb.Type.fields now have an
1545 `is_base_class' attribute.
1547 ** The new method gdb.Type.range returns the range of an array type.
1549 ** The new method gdb.parse_and_eval can be used to parse and
1550 evaluate an expression.
1552 * New remote packets
1555 Define a trace state variable.
1558 Get the current value of a trace state variable.
1561 Set desired tracing behavior upon disconnection.
1564 Set the trace buffer to be linear or circular.
1567 Get data about the tracepoints currently in use.
1571 Process record now works correctly with hardware watchpoints.
1573 Multiple bug fixes have been made to the mips-irix port, making it
1574 much more reliable. In particular:
1575 - Debugging threaded applications is now possible again. Previously,
1576 GDB would hang while starting the program, or while waiting for
1577 the program to stop at a breakpoint.
1578 - Attaching to a running process no longer hangs.
1579 - An error occurring while loading a core file has been fixed.
1580 - Changing the value of the PC register now works again. This fixes
1581 problems observed when using the "jump" command, or when calling
1582 a function from GDB, or even when assigning a new value to $pc.
1583 - With the "finish" and "return" commands, the return value for functions
1584 returning a small array is now correctly printed.
1585 - It is now possible to break on shared library code which gets executed
1586 during a shared library init phase (code executed while executing
1587 their .init section). Previously, the breakpoint would have no effect.
1588 - GDB is now able to backtrace through the signal handler for
1589 non-threaded programs.
1591 PIE (Position Independent Executable) programs debugging is now supported.
1592 This includes debugging execution of PIC (Position Independent Code) shared
1593 libraries although for that, it should be possible to run such libraries as an
1596 *** Changes in GDB 7.0
1598 * GDB now has an interface for JIT compilation. Applications that
1599 dynamically generate code can create symbol files in memory and register
1600 them with GDB. For users, the feature should work transparently, and
1601 for JIT developers, the interface is documented in the GDB manual in the
1602 "JIT Compilation Interface" chapter.
1604 * Tracepoints may now be conditional. The syntax is as for
1605 breakpoints; either an "if" clause appended to the "trace" command,
1606 or the "condition" command is available. GDB sends the condition to
1607 the target for evaluation using the same bytecode format as is used
1608 for tracepoint actions.
1610 * The disassemble command now supports: an optional /r modifier, print the
1611 raw instructions in hex as well as in symbolic form, and an optional /m
1612 modifier to print mixed source+assembly.
1614 * Process record and replay
1616 In a architecture environment that supports ``process record and
1617 replay'', ``process record and replay'' target can record a log of
1618 the process execution, and replay it with both forward and reverse
1621 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1622 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1623 set execution-direction {forward|reverse}, for targets that support
1626 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1627 feature is available with a native GDB running on kernel version
1630 * GDB now has support for multi-byte and wide character sets on the
1631 target. Strings whose character type is wchar_t, char16_t, or
1632 char32_t are now correctly printed. GDB supports wide- and unicode-
1633 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1634 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1635 `printf'. This feature requires iconv to work properly; if your
1636 system does not have a working iconv, GDB can use GNU libiconv. See
1637 the installation instructions for more information.
1639 * GDB now supports automatic retrieval of shared library files from
1640 remote targets. To use this feature, specify a system root that begins
1641 with the `remote:' prefix, either via the `set sysroot' command or via
1642 the `--with-sysroot' configure-time option.
1644 * "info sharedlibrary" now takes an optional regex of libraries to show,
1645 and it now reports if a shared library has no debugging information.
1647 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1648 now complete on file names.
1650 * When completing in expressions, gdb will attempt to limit
1651 completions to allowable structure or union fields, where appropriate.
1652 For instance, consider:
1654 # struct example { int f1; double f2; };
1655 # struct example variable;
1658 If the user types TAB at the end of this command line, the available
1659 completions will be "f1" and "f2".
1661 * Inlined functions are now supported. They show up in backtraces, and
1662 the "step", "next", and "finish" commands handle them automatically.
1664 * GDB now supports the token-splicing (##) and stringification (#)
1665 operators when expanding macros. It also supports variable-arity
1668 * GDB now supports inspecting extra signal information, exported by
1669 the new $_siginfo convenience variable. The feature is currently
1670 implemented on linux ARM, i386 and amd64.
1672 * GDB can now display the VFP floating point registers and NEON vector
1673 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1674 can provide these registers (requires Linux 2.6.30 or later). Remote
1675 and simulator targets may also provide them.
1677 * New remote packets
1680 Search memory for a sequence of bytes.
1683 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1684 operation over reliable transport links. Use of this packet is
1685 controlled by the `set remote noack-packet' command.
1688 Kill the process with the specified process ID. Use this in preference
1689 to `k' when multiprocess protocol extensions are supported.
1692 Obtains additional operating system information
1696 Read or write additional signal information.
1698 * Removed remote protocol undocumented extension
1700 An undocumented extension to the remote protocol's `S' stop reply
1701 packet that permited the stub to pass a process id was removed.
1702 Remote servers should use the `T' stop reply packet instead.
1704 * GDB now supports multiple function calling conventions according to the
1705 DWARF-2 DW_AT_calling_convention function attribute.
1707 * The SH target utilizes the aforementioned change to distinguish between gcc
1708 and Renesas calling convention. It also adds the new CLI commands
1709 `set/show sh calling-convention'.
1711 * GDB can now read compressed debug sections, as produced by GNU gold
1712 with the --compress-debug-sections=zlib flag.
1714 * 64-bit core files are now supported on AIX.
1716 * Thread switching is now supported on Tru64.
1718 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1719 which will be allocated using malloc later in program execution.
1721 * The qXfer:libraries:read remote procotol packet now allows passing a
1722 list of section offsets.
1724 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1725 conditions handling signals delivered during attach or thread creation
1726 have also been fixed.
1728 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1729 From the user's standpoint, all unqualified instances of True and False
1730 are treated as the standard definitions, regardless of context.
1732 * GDB now parses C++ symbol and type names more flexibly. For
1735 template<typename T> class C { };
1738 GDB will now correctly handle all of:
1740 ptype C<char const *>
1741 ptype C<char const*>
1742 ptype C<const char *>
1743 ptype C<const char*>
1745 * New features in the GDB remote stub, gdbserver
1747 - The "--wrapper" command-line argument tells gdbserver to use a
1748 wrapper program to launch programs for debugging.
1750 - On PowerPC and S/390 targets, it is now possible to use a single
1751 gdbserver executable to debug both 32-bit and 64-bit programs.
1752 (This requires gdbserver itself to be built as a 64-bit executable.)
1754 - gdbserver uses the new noack protocol mode for TCP connections to
1755 reduce communications latency, if also supported and enabled in GDB.
1757 - Support for the sparc64-linux-gnu target is now included in
1760 - The amd64-linux build of gdbserver now supports debugging both
1761 32-bit and 64-bit programs.
1763 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1764 now support hardware watchpoints, and will use them automatically
1769 GDB now has support for scripting using Python. Whether this is
1770 available is determined at configure time.
1772 New GDB commands can now be written in Python.
1774 * Ada tasking support
1776 Ada tasks can now be inspected in GDB. The following commands have
1780 Print the list of Ada tasks.
1782 Print detailed information about task number N.
1784 Print the task number of the current task.
1786 Switch the context of debugging to task number N.
1788 * Support for user-defined prefixed commands. The "define" command can
1789 add new commands to existing prefixes, e.g. "target".
1791 * Multi-inferior, multi-process debugging.
1793 GDB now has generalized support for multi-inferior debugging. See
1794 "Debugging Multiple Inferiors" in the manual for more information.
1795 Although availability still depends on target support, the command
1796 set is more uniform now. The GNU/Linux specific multi-forks support
1797 has been migrated to this new framework. This implied some user
1798 visible changes; see "New commands" and also "Removed commands"
1801 * Target descriptions can now describe the target OS ABI. See the
1802 "Target Description Format" section in the user manual for more
1805 * Target descriptions can now describe "compatible" architectures
1806 to indicate that the target can execute applications for a different
1807 architecture in addition to those for the main target architecture.
1808 See the "Target Description Format" section in the user manual for
1811 * Multi-architecture debugging.
1813 GDB now includes general supports for debugging applications on
1814 hybrid systems that use more than one single processor architecture
1815 at the same time. Each such hybrid architecture still requires
1816 specific support to be added. The only hybrid architecture supported
1817 in this version of GDB is the Cell Broadband Engine.
1819 * GDB now supports integrated debugging of Cell/B.E. applications that
1820 use both the PPU and SPU architectures. To enable support for hybrid
1821 Cell/B.E. debugging, you need to configure GDB to support both the
1822 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1823 --enable-targets configure option.
1825 * Non-stop mode debugging.
1827 For some targets, GDB now supports an optional mode of operation in
1828 which you can examine stopped threads while other threads continue
1829 to execute freely. This is referred to as non-stop mode, with the
1830 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1831 section in the user manual for more information.
1833 To be able to support remote non-stop debugging, a remote stub needs
1834 to implement the non-stop mode remote protocol extensions, as
1835 described in the "Remote Non-Stop" section of the user manual. The
1836 GDB remote stub, gdbserver, has been adjusted to support these
1837 extensions on linux targets.
1839 * New commands (for set/show, see "New options" below)
1841 catch syscall [NAME(S) | NUMBER(S)]
1842 Catch system calls. Arguments, which should be names of system
1843 calls or their numbers, mean catch only those syscalls. Without
1844 arguments, every syscall will be caught. When the inferior issues
1845 any of the specified syscalls, GDB will stop and announce the system
1846 call, both when it is called and when its call returns. This
1847 feature is currently available with a native GDB running on the
1848 Linux Kernel, under the following architectures: x86, x86_64,
1849 PowerPC and PowerPC64.
1851 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1853 Search memory for a sequence of bytes.
1855 maint set python print-stack
1856 maint show python print-stack
1857 Show a stack trace when an error is encountered in a Python script.
1860 Invoke CODE by passing it to the Python interpreter.
1865 These allow macros to be defined, undefined, and listed
1869 Show operating system information about processes.
1872 List the inferiors currently under GDB's control.
1875 Switch focus to inferior number NUM.
1878 Detach from inferior number NUM.
1881 Kill inferior number NUM.
1885 set spu stop-on-load
1886 show spu stop-on-load
1887 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1889 set spu auto-flush-cache
1890 show spu auto-flush-cache
1891 Control whether to automatically flush the software-managed cache
1892 during Cell/B.E. debugging.
1894 set sh calling-convention
1895 show sh calling-convention
1896 Control the calling convention used when calling SH target functions.
1899 show debug timestamp
1900 Control display of timestamps with GDB debugging output.
1902 set disassemble-next-line
1903 show disassemble-next-line
1904 Control display of disassembled source lines or instructions when
1907 set remote noack-packet
1908 show remote noack-packet
1909 Set/show the use of remote protocol QStartNoAckMode packet. See above
1910 under "New remote packets."
1912 set remote query-attached-packet
1913 show remote query-attached-packet
1914 Control use of remote protocol `qAttached' (query-attached) packet.
1916 set remote read-siginfo-object
1917 show remote read-siginfo-object
1918 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1921 set remote write-siginfo-object
1922 show remote write-siginfo-object
1923 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1926 set remote reverse-continue
1927 show remote reverse-continue
1928 Control use of remote protocol 'bc' (reverse-continue) packet.
1930 set remote reverse-step
1931 show remote reverse-step
1932 Control use of remote protocol 'bs' (reverse-step) packet.
1934 set displaced-stepping
1935 show displaced-stepping
1936 Control displaced stepping mode. Displaced stepping is a way to
1937 single-step over breakpoints without removing them from the debuggee.
1938 Also known as "out-of-line single-stepping".
1941 show debug displaced
1942 Control display of debugging info for displaced stepping.
1944 maint set internal-error
1945 maint show internal-error
1946 Control what GDB does when an internal error is detected.
1948 maint set internal-warning
1949 maint show internal-warning
1950 Control what GDB does when an internal warning is detected.
1955 Use a wrapper program to launch programs for debugging.
1957 set multiple-symbols (all|ask|cancel)
1958 show multiple-symbols
1959 The value of this variable can be changed to adjust the debugger behavior
1960 when an expression or a breakpoint location contains an ambiguous symbol
1961 name (an overloaded function name, for instance).
1963 set breakpoint always-inserted
1964 show breakpoint always-inserted
1965 Keep breakpoints always inserted in the target, as opposed to inserting
1966 them when resuming the target, and removing them when the target stops.
1967 This option can improve debugger performance on slow remote targets.
1969 set arm fallback-mode (arm|thumb|auto)
1970 show arm fallback-mode
1971 set arm force-mode (arm|thumb|auto)
1973 These commands control how ARM GDB determines whether instructions
1974 are ARM or Thumb. The default for both settings is auto, which uses
1975 the current CPSR value for instructions without symbols; previous
1976 versions of GDB behaved as if "set arm fallback-mode arm".
1978 set disable-randomization
1979 show disable-randomization
1980 Standalone programs run with the virtual address space randomization enabled
1981 by default on some platforms. This option keeps the addresses stable across
1982 multiple debugging sessions.
1986 Control whether other threads are stopped or not when some thread hits
1991 Requests that asynchronous execution is enabled in the target, if available.
1992 In this case, it's possible to resume target in the background, and interact
1993 with GDB while the target is running. "show target-async" displays the
1994 current state of asynchronous execution of the target.
1996 set target-wide-charset
1997 show target-wide-charset
1998 The target-wide-charset is the name of the character set that GDB
1999 uses when printing characters whose type is wchar_t.
2001 set tcp auto-retry (on|off)
2003 set tcp connect-timeout
2004 show tcp connect-timeout
2005 These commands allow GDB to retry failed TCP connections to a remote stub
2006 with a specified timeout period; this is useful if the stub is launched
2007 in parallel with GDB but may not be ready to accept connections immediately.
2009 set libthread-db-search-path
2010 show libthread-db-search-path
2011 Control list of directories which GDB will search for appropriate
2014 set schedule-multiple (on|off)
2015 show schedule-multiple
2016 Allow GDB to resume all threads of all processes or only threads of
2017 the current process.
2021 Use more aggressive caching for accesses to the stack. This improves
2022 performance of remote debugging (particularly backtraces) without
2023 affecting correctness.
2025 set interactive-mode (on|off|auto)
2026 show interactive-mode
2027 Control whether GDB runs in interactive mode (on) or not (off).
2028 When in interactive mode, GDB waits for the user to answer all
2029 queries. Otherwise, GDB does not wait and assumes the default
2030 answer. When set to auto (the default), GDB determines which
2031 mode to use based on the stdin settings.
2036 For program forks, this is replaced by the new more generic `info
2037 inferiors' command. To list checkpoints, you can still use the
2038 `info checkpoints' command, which was an alias for the `info forks'
2042 Replaced by the new `inferior' command. To switch between
2043 checkpoints, you can still use the `restart' command, which was an
2044 alias for the `fork' command.
2047 This is removed, since some targets don't have a notion of
2048 processes. To switch between processes, you can still use the
2049 `inferior' command using GDB's own inferior number.
2052 For program forks, this is replaced by the new more generic `kill
2053 inferior' command. To delete a checkpoint, you can still use the
2054 `delete checkpoint' command, which was an alias for the `delete
2058 For program forks, this is replaced by the new more generic `detach
2059 inferior' command. To detach a checkpoint, you can still use the
2060 `detach checkpoint' command, which was an alias for the `detach
2063 * New native configurations
2065 x86/x86_64 Darwin i[34567]86-*-darwin*
2067 x86_64 MinGW x86_64-*-mingw*
2071 Lattice Mico32 lm32-*
2072 x86 DICOS i[34567]86-*-dicos*
2073 x86_64 DICOS x86_64-*-dicos*
2076 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2077 (mingw32ce) debugging.
2083 These commands were actually not implemented on any target.
2085 *** Changes in GDB 6.8
2087 * New native configurations
2089 NetBSD/hppa hppa*-*netbsd*
2090 Xtensa GNU/Linux xtensa*-*-linux*
2094 NetBSD/hppa hppa*-*-netbsd*
2095 Xtensa GNU/Lunux xtensa*-*-linux*
2097 * Change in command line behavior -- corefiles vs. process ids.
2099 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2100 attaching to process NUMBER fails, GDB no longer attempts to open a
2101 core file named NUMBER. Attaching to a program using the -c option
2102 is no longer supported. Instead, use the '-p' or '--pid' options.
2104 * GDB can now be built as a native debugger for debugging Windows x86
2105 (mingw32) Portable Executable (PE) programs.
2107 * Pending breakpoints no longer change their number when their address
2110 * GDB now supports breakpoints with multiple locations,
2111 including breakpoints on C++ constructors, inside C++ templates,
2112 and in inlined functions.
2114 * GDB's ability to debug optimized code has been improved. GDB more
2115 accurately identifies function bodies and lexical blocks that occupy
2116 more than one contiguous range of addresses.
2118 * Target descriptions can now describe registers for PowerPC.
2120 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2121 registers on PowerPC targets.
2123 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2124 targets even when the libthread_db library is not available.
2126 * The GDB remote stub, gdbserver, now supports the new file transfer
2127 commands (remote put, remote get, and remote delete).
2129 * The GDB remote stub, gdbserver, now supports run and attach in
2130 extended-remote mode.
2132 * hppa*64*-*-hpux11* target broken
2133 The debugger is unable to start a program and fails with the following
2134 error: "Error trying to get information about dynamic linker".
2135 The gdb-6.7 release is also affected.
2137 * GDB now supports the --enable-targets= configure option to allow
2138 building a single GDB executable that supports multiple remote
2139 target architectures.
2141 * GDB now supports debugging C and C++ programs which use the
2142 Decimal Floating Point extension. In addition, the PowerPC target
2143 now has a set of pseudo-registers to inspect decimal float values
2144 stored in two consecutive float registers.
2146 * The -break-insert MI command can optionally create pending
2149 * Improved support for debugging Ada
2150 Many improvements to the Ada language support have been made. These
2152 - Better support for Ada2005 interface types
2153 - Improved handling of arrays and slices in general
2154 - Better support for Taft-amendment types
2155 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2157 - Improved command completion in Ada
2160 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2165 set print frame-arguments (all|scalars|none)
2166 show print frame-arguments
2167 The value of this variable can be changed to control which argument
2168 values should be printed by the debugger when displaying a frame.
2173 Transfer files to and from a remote target, and delete remote files.
2180 Transfer files to and from a remote target, and delete remote files.
2182 * New remote packets
2189 Open, close, read, write, and delete files on the remote system.
2192 Attach to an existing process on the remote system, in extended-remote
2196 Run a new process on the remote system, in extended-remote mode.
2198 *** Changes in GDB 6.7
2200 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2201 bfd, libiberty and opcodes, as revealed by static analysis donated by
2202 Coverity, Inc. (http://scan.coverity.com).
2204 * When looking up multiply-defined global symbols, GDB will now prefer the
2205 symbol definition in the current shared library if it was built using the
2206 -Bsymbolic linker option.
2208 * When the Text User Interface (TUI) is not configured, GDB will now
2209 recognize the -tui command-line option and print a message that the TUI
2212 * The GDB remote stub, gdbserver, now has lower overhead for high
2213 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2215 * GDB for MIPS targets now autodetects whether a remote target provides
2216 32-bit or 64-bit register values.
2218 * Support for C++ member pointers has been improved.
2220 * GDB now understands XML target descriptions, which specify the
2221 target's overall architecture. GDB can read a description from
2222 a local file or over the remote serial protocol.
2224 * Vectors of single-byte data use a new integer type which is not
2225 automatically displayed as character or string data.
2227 * The /s format now works with the print command. It displays
2228 arrays of single-byte integers and pointers to single-byte integers
2231 * Target descriptions can now describe target-specific registers,
2232 for architectures which have implemented the support (currently
2233 only ARM, M68K, and MIPS).
2235 * GDB and the GDB remote stub, gdbserver, now support the XScale
2238 * The GDB remote stub, gdbserver, has been updated to support
2239 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2240 has been rewritten to use the standard GDB remote protocol.
2242 * GDB can now step into C++ functions which are called through thunks.
2244 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2246 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2247 layout. It also supports a TextSeg= and DataSeg= response when only
2248 segment base addresses (rather than offsets) are available.
2250 * The /i format now outputs any trailing branch delay slot instructions
2251 immediately following the last instruction within the count specified.
2253 * The GDB remote protocol "T" stop reply packet now supports a
2254 "library" response. Combined with the new "qXfer:libraries:read"
2255 packet, this response allows GDB to debug shared libraries on targets
2256 where the operating system manages the list of loaded libraries (e.g.
2257 Windows and SymbianOS).
2259 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2260 (DLLs) on Windows and Windows CE targets.
2262 * GDB now supports a faster verification that a .debug file matches its binary
2263 according to its build-id signature, if the signature is present.
2269 Enable or disable hardware flow control (RTS/CTS) on the serial port
2270 when debugging using remote targets.
2272 set mem inaccessible-by-default
2273 show mem inaccessible-by-default
2274 If the target supplies a memory map, for instance via the remote
2275 protocol's "qXfer:memory-map:read" packet, setting this variable
2276 prevents GDB from accessing memory outside the memory map. This
2277 is useful for targets with memory mapped registers or which react
2278 badly to accesses of unmapped address space.
2280 set breakpoint auto-hw
2281 show breakpoint auto-hw
2282 If the target supplies a memory map, for instance via the remote
2283 protocol's "qXfer:memory-map:read" packet, setting this variable
2284 lets GDB use hardware breakpoints automatically for memory regions
2285 where it can not use software breakpoints. This covers both the
2286 "break" command and internal breakpoints used for other commands
2287 including "next" and "finish".
2290 catch exception unhandled
2291 Stop the program execution when Ada exceptions are raised.
2294 Stop the program execution when an Ada assertion failed.
2298 Set an alternate system root for target files. This is a more
2299 general version of "set solib-absolute-prefix", which is now
2300 an alias to "set sysroot".
2303 Provide extended SPU facility status information. This set of
2304 commands is available only when debugging the Cell/B.E. SPU
2307 * New native configurations
2309 OpenBSD/sh sh*-*openbsd*
2312 unset tdesc filename
2314 Use the specified local file as an XML target description, and do
2315 not query the target for its built-in description.
2319 OpenBSD/sh sh*-*-openbsd*
2320 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2321 Toshiba Media Processor mep-elf
2323 * New remote packets
2326 Ignore the specified signals; pass them directly to the debugged program
2327 without stopping other threads or reporting them to GDB.
2329 qXfer:features:read:
2330 Read an XML target description from the target, which describes its
2335 Read or write contents of an spufs file on the target system. These
2336 packets are available only on the Cell/B.E. SPU architecture.
2338 qXfer:libraries:read:
2339 Report the loaded shared libraries. Combined with new "T" packet
2340 response, this packet allows GDB to debug shared libraries on
2341 targets where the operating system manages the list of loaded
2342 libraries (e.g. Windows and SymbianOS).
2346 Support for these obsolete configurations has been removed.
2354 i[34567]86-*-lynxos*
2355 i[34567]86-*-netware*
2356 i[34567]86-*-sco3.2v5*
2357 i[34567]86-*-sco3.2v4*
2359 i[34567]86-*-sysv4.2*
2362 i[34567]86-*-unixware2*
2363 i[34567]86-*-unixware*
2372 * Other removed features
2379 Various m68k-only ROM monitors.
2386 Various Renesas ROM monitors and debugging interfaces for SH and
2391 Support for a Macraigor serial interface to on-chip debugging.
2392 GDB does not directly support the newer parallel or USB
2397 A debug information format. The predecessor to DWARF 2 and
2398 DWARF 3, which are still supported.
2400 Support for the HP aCC compiler on HP-UX/PA-RISC
2402 SOM-encapsulated symbolic debugging information, automatic
2403 invocation of pxdb, and the aCC custom C++ ABI. This does not
2404 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2405 with aCC can still be debugged on an assembly level.
2407 MIPS ".pdr" sections
2409 A MIPS-specific format used to describe stack frame layout
2410 in debugging information.
2414 GDB could work with an older version of Guile to debug
2415 the interpreter and Scheme programs running in it.
2417 set mips stack-arg-size
2418 set mips saved-gpreg-size
2420 Use "set mips abi" to control parameter passing for MIPS.
2422 *** Changes in GDB 6.6
2427 Cell Broadband Engine SPU spu-elf
2429 * GDB can now be configured as a cross-debugger targeting native Windows
2430 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2431 running on a Windows system over TCP/IP to debug Windows programs.
2433 * The GDB remote stub, gdbserver, has been updated to support Windows and
2434 Cygwin debugging. Both single-threaded and multi-threaded programs are
2437 * The "set trust-readonly-sections" command works again. This command was
2438 broken in GDB 6.3, 6.4, and 6.5.
2440 * The "load" command now supports writing to flash memory, if the remote
2441 stub provides the required support.
2443 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2444 longer requires symbolic debug information (e.g. DWARF-2).
2449 unset substitute-path
2450 show substitute-path
2451 Manage a list of substitution rules that GDB uses to rewrite the name
2452 of the directories where the sources are located. This can be useful
2453 for instance when the sources were moved to a different location
2454 between compilation and debugging.
2458 Print each CLI command as it is executed. Each command is prefixed with
2459 a number of `+' symbols representing the nesting depth.
2460 The source command now has a `-v' option to enable the same feature.
2464 The ARM Demon monitor support (RDP protocol, "target rdp").
2466 Kernel Object Display, an embedded debugging feature which only worked with
2467 an obsolete version of Cisco IOS.
2469 The 'set download-write-size' and 'show download-write-size' commands.
2471 * New remote packets
2474 Tell a stub about GDB client features, and request remote target features.
2475 The first feature implemented is PacketSize, which allows the target to
2476 specify the size of packets it can handle - to minimize the number of
2477 packets required and improve performance when connected to a remote
2481 Fetch an OS auxilliary vector from the remote stub. This packet is a
2482 more efficient replacement for qPart:auxv:read.
2484 qXfer:memory-map:read:
2485 Fetch a memory map from the remote stub, including information about
2486 RAM, ROM, and flash memory devices.
2491 Erase and program a flash memory device.
2493 * Removed remote packets
2496 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2497 used it, and only gdbserver implemented it.
2499 *** Changes in GDB 6.5
2503 Renesas M32C/M16C m32c-elf
2505 Morpho Technologies ms1 ms1-elf
2509 init-if-undefined Initialize a convenience variable, but
2510 only if it doesn't already have a value.
2512 The following commands are presently only implemented for native GNU/Linux:
2514 checkpoint Save a snapshot of the program state.
2516 restart <n> Return the program state to a
2517 previously saved state.
2519 info checkpoints List currently saved checkpoints.
2521 delete-checkpoint <n> Delete a previously saved checkpoint.
2523 set|show detach-on-fork Tell gdb whether to detach from a newly
2524 forked process, or to keep debugging it.
2526 info forks List forks of the user program that
2527 are available to be debugged.
2529 fork <n> Switch to debugging one of several
2530 forks of the user program that are
2531 available to be debugged.
2533 delete-fork <n> Delete a fork from the list of forks
2534 that are available to be debugged (and
2535 kill the forked process).
2537 detach-fork <n> Delete a fork from the list of forks
2538 that are available to be debugged (and
2539 allow the process to continue).
2543 Morpho Technologies ms2 ms1-elf
2545 * Improved Windows host support
2547 GDB now builds as a cross debugger hosted on i686-mingw32, including
2548 native console support, and remote communications using either
2549 network sockets or serial ports.
2551 * Improved Modula-2 language support
2553 GDB can now print most types in the Modula-2 syntax. This includes:
2554 basic types, set types, record types, enumerated types, range types,
2555 pointer types and ARRAY types. Procedure var parameters are correctly
2556 printed and hexadecimal addresses and character constants are also
2557 written in the Modula-2 syntax. Best results can be obtained by using
2558 GNU Modula-2 together with the -gdwarf-2 command line option.
2562 The ARM rdi-share module.
2564 The Netware NLM debug server.
2566 *** Changes in GDB 6.4
2568 * New native configurations
2570 OpenBSD/arm arm*-*-openbsd*
2571 OpenBSD/mips64 mips64-*-openbsd*
2575 Morpho Technologies ms1 ms1-elf
2577 * New command line options
2579 --batch-silent As for --batch, but totally silent.
2580 --return-child-result The debugger will exist with the same value
2581 the child (debugged) program exited with.
2582 --eval-command COMMAND, -ex COMMAND
2583 Execute a single GDB CLI command. This may be
2584 specified multiple times and in conjunction
2585 with the --command (-x) option.
2587 * Deprecated commands removed
2589 The following commands, that were deprecated in 2000, have been
2593 set|show arm disassembly-flavor set|show arm disassembler
2594 othernames set arm disassembler
2595 set|show remotedebug set|show debug remote
2596 set|show archdebug set|show debug arch
2597 set|show eventdebug set|show debug event
2600 * New BSD user-level threads support
2602 It is now possible to debug programs using the user-level threads
2603 library on OpenBSD and FreeBSD. Currently supported (target)
2606 FreeBSD/amd64 x86_64-*-freebsd*
2607 FreeBSD/i386 i386-*-freebsd*
2608 OpenBSD/i386 i386-*-openbsd*
2610 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2611 are not yet supported.
2613 * New support for Matsushita MN10300 w/sim added
2614 (Work in progress). mn10300-elf.
2616 * REMOVED configurations and files
2618 VxWorks and the XDR protocol *-*-vxworks
2619 Motorola MCORE mcore-*-*
2620 National Semiconductor NS32000 ns32k-*-*
2622 * New "set print array-indexes" command
2624 After turning this setting "on", GDB prints the index of each element
2625 when displaying arrays. The default is "off" to preserve the previous
2628 * VAX floating point support
2630 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2632 * User-defined command support
2634 In addition to using $arg0..$arg9 for argument passing, it is now possible
2635 to use $argc to determine now many arguments have been passed. See the
2636 section on user-defined commands in the user manual for more information.
2638 *** Changes in GDB 6.3:
2640 * New command line option
2642 GDB now accepts -l followed by a number to set the timeout for remote
2645 * GDB works with GCC -feliminate-dwarf2-dups
2647 GDB now supports a more compact representation of DWARF-2 debug
2648 information using DW_FORM_ref_addr references. These are produced
2649 by GCC with the option -feliminate-dwarf2-dups and also by some
2650 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2651 to use -feliminate-dwarf2-dups.
2653 * Internationalization
2655 When supported by the host system, GDB will be built with
2656 internationalization (libintl). The task of marking up the sources is
2657 continued, we're looking forward to our first translation.
2661 Initial support for debugging programs compiled with the GNAT
2662 implementation of the Ada programming language has been integrated
2663 into GDB. In this release, support is limited to expression evaluation.
2665 * New native configurations
2667 GNU/Linux/m32r m32r-*-linux-gnu
2671 GDB's remote protocol now includes support for the 'p' packet. This
2672 packet is used to fetch individual registers from a remote inferior.
2674 * END-OF-LIFE registers[] compatibility module
2676 GDB's internal register infrastructure has been completely rewritten.
2677 The new infrastructure making possible the implementation of key new
2678 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2681 GDB 6.3 will be the last release to include the the registers[]
2682 compatibility module that allowed out-of-date configurations to
2683 continue to work. This change directly impacts the following
2693 powerpc bdm protocol
2695 Unless there is activity to revive these configurations, they will be
2696 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2698 * OBSOLETE configurations and files
2700 Configurations that have been declared obsolete in this release have
2701 been commented out. Unless there is activity to revive these
2702 configurations, the next release of GDB will have their sources
2703 permanently REMOVED.
2712 *** Changes in GDB 6.2.1:
2714 * MIPS `break main; run' gave an heuristic-fence-post warning
2716 When attempting to run even a simple program, a warning about
2717 heuristic-fence-post being hit would be reported. This problem has
2720 * MIPS IRIX 'long double' crashed GDB
2722 When examining a long double variable, GDB would get a segmentation
2723 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2724 IRIX long double values).
2728 A bug in the VAX stack code was causing problems with the "next"
2729 command. This problem has been fixed.
2731 *** Changes in GDB 6.2:
2733 * Fix for ``many threads''
2735 On GNU/Linux systems that use the NPTL threads library, a program
2736 rapidly creating and deleting threads would confuse GDB leading to the
2739 ptrace: No such process.
2740 thread_db_get_info: cannot get thread info: generic error
2742 This problem has been fixed.
2744 * "-async" and "-noasync" options removed.
2746 Support for the broken "-noasync" option has been removed (it caused
2749 * New ``start'' command.
2751 This command runs the program until the begining of the main procedure.
2753 * New BSD Kernel Data Access Library (libkvm) interface
2755 Using ``target kvm'' it is now possible to debug kernel core dumps and
2756 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2757 platforms. Currently supported (native-only) configurations are:
2759 FreeBSD/amd64 x86_64-*-freebsd*
2760 FreeBSD/i386 i?86-*-freebsd*
2761 NetBSD/i386 i?86-*-netbsd*
2762 NetBSD/m68k m68*-*-netbsd*
2763 NetBSD/sparc sparc-*-netbsd*
2764 OpenBSD/amd64 x86_64-*-openbsd*
2765 OpenBSD/i386 i?86-*-openbsd*
2766 OpenBSD/m68k m68*-openbsd*
2767 OpenBSD/sparc sparc-*-openbsd*
2769 * Signal trampoline code overhauled
2771 Many generic problems with GDB's signal handling code have been fixed.
2772 These include: backtraces through non-contiguous stacks; recognition
2773 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2774 call; backtrace through a signal trampoline; step into and out of
2775 signal handlers; and single-stepping in the signal trampoline.
2777 Please note that kernel bugs are a limiting factor here. These
2778 features have been shown to work on an s390 GNU/Linux system that
2779 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2781 * Cygwin support for DWARF 2 added.
2783 * New native configurations
2785 GNU/Linux/hppa hppa*-*-linux*
2786 OpenBSD/hppa hppa*-*-openbsd*
2787 OpenBSD/m68k m68*-*-openbsd*
2788 OpenBSD/m88k m88*-*-openbsd*
2789 OpenBSD/powerpc powerpc-*-openbsd*
2790 NetBSD/vax vax-*-netbsd*
2791 OpenBSD/vax vax-*-openbsd*
2793 * END-OF-LIFE frame compatibility module
2795 GDB's internal frame infrastructure has been completely rewritten.
2796 The new infrastructure making it possible to support key new features
2797 including DWARF 2 Call Frame Information. To aid in the task of
2798 migrating old configurations to this new infrastructure, a
2799 compatibility module, that allowed old configurations to continue to
2800 work, was also included.
2802 GDB 6.2 will be the last release to include this frame compatibility
2803 module. This change directly impacts the following configurations:
2813 Unless there is activity to revive these configurations, they will be
2814 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2816 * REMOVED configurations and files
2818 Sun 3, running SunOS 3 m68*-*-sunos3*
2819 Sun 3, running SunOS 4 m68*-*-sunos4*
2820 Sun 2, running SunOS 3 m68000-*-sunos3*
2821 Sun 2, running SunOS 4 m68000-*-sunos4*
2822 Motorola 680x0 running LynxOS m68*-*-lynxos*
2823 AT&T 3b1/Unix pc m68*-att-*
2824 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2825 decstation mips-dec-* mips-little-*
2826 riscos mips-*-riscos* mips-*-sysv*
2827 sonymips mips-sony-*
2828 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2830 *** Changes in GDB 6.1.1:
2832 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2834 The TUI (Text-mode User Interface) is now built as part of a default
2835 GDB configuration. It is enabled by either selecting the TUI with the
2836 command line option "-i=tui" or by running the separate "gdbtui"
2837 program. For more information on the TUI, see the manual "Debugging
2840 * Pending breakpoint support (also included in GDB 6.1)
2842 Support has been added to allow you to specify breakpoints in shared
2843 libraries that have not yet been loaded. If a breakpoint location
2844 cannot be found, and the "breakpoint pending" option is set to auto,
2845 GDB queries you if you wish to make the breakpoint pending on a future
2846 shared-library load. If and when GDB resolves the breakpoint symbol,
2847 the pending breakpoint is removed as one or more regular breakpoints
2850 Pending breakpoints are very useful for GCJ Java debugging.
2852 * Fixed ISO-C build problems
2854 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2855 non ISO-C code that stopped them being built using a more strict ISO-C
2856 compiler (e.g., IBM's C compiler).
2858 * Fixed build problem on IRIX 5
2860 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2861 wasn't able to compile compile on an IRIX 5 system.
2863 * Added execute permission to gdb/gdbserver/configure
2865 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2866 permission. This bug would cause configure to fail on a number of
2867 systems (Solaris, IRIX). Ref: server/519.
2869 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2871 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2872 has been updated to use constant array sizes.
2874 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2876 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2877 its generated DWARF Call Frame Info. This encoding was causing GDB to
2878 panic, that panic has been fixed. Ref: gdb/1628.
2880 * Fixed a problem when examining parameters in shared library code.
2882 When examining parameters in optimized shared library code generated
2883 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2884 not available''. GDB now correctly displays the variable's value.
2886 *** Changes in GDB 6.1:
2888 * Removed --with-mmalloc
2890 Support for the mmalloc memory manager has been removed, as it
2891 conflicted with the internal gdb byte cache.
2893 * Changes in AMD64 configurations
2895 The AMD64 target now includes the %cs and %ss registers. As a result
2896 the AMD64 remote protocol has changed; this affects the floating-point
2897 and SSE registers. If you rely on those registers for your debugging,
2898 you should upgrade gdbserver on the remote side.
2900 * Revised SPARC target
2902 The SPARC target has been completely revised, incorporating the
2903 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2904 support for LynxOS and SunOS 4 has been dropped. Calling functions
2905 from within GDB on operating systems with a non-executable stack
2906 (Solaris, OpenBSD) now works.
2910 GDB has a new C++ demangler which does a better job on the mangled
2911 names generated by current versions of g++. It also runs faster, so
2912 with this and other changes gdb should now start faster on large C++
2915 * DWARF 2 Location Expressions
2917 GDB support for location expressions has been extended to support function
2918 arguments and frame bases. Older versions of GDB could crash when they
2921 * C++ nested types and namespaces
2923 GDB's support for nested types and namespaces in C++ has been
2924 improved, especially if you use the DWARF 2 debugging format. (This
2925 is the default for recent versions of GCC on most platforms.)
2926 Specifically, if you have a class "Inner" defined within a class or
2927 namespace "Outer", then GDB realizes that the class's name is
2928 "Outer::Inner", not simply "Inner". This should greatly reduce the
2929 frequency of complaints about not finding RTTI symbols. In addition,
2930 if you are stopped at inside of a function defined within a namespace,
2931 GDB modifies its name lookup accordingly.
2933 * New native configurations
2935 NetBSD/amd64 x86_64-*-netbsd*
2936 OpenBSD/amd64 x86_64-*-openbsd*
2937 OpenBSD/alpha alpha*-*-openbsd*
2938 OpenBSD/sparc sparc-*-openbsd*
2939 OpenBSD/sparc64 sparc64-*-openbsd*
2941 * New debugging protocols
2943 M32R with SDI protocol m32r-*-elf*
2945 * "set prompt-escape-char" command deleted.
2947 The command "set prompt-escape-char" has been deleted. This command,
2948 and its very obscure effet on GDB's prompt, was never documented,
2949 tested, nor mentioned in the NEWS file.
2951 * OBSOLETE configurations and files
2953 Configurations that have been declared obsolete in this release have
2954 been commented out. Unless there is activity to revive these
2955 configurations, the next release of GDB will have their sources
2956 permanently REMOVED.
2958 Sun 3, running SunOS 3 m68*-*-sunos3*
2959 Sun 3, running SunOS 4 m68*-*-sunos4*
2960 Sun 2, running SunOS 3 m68000-*-sunos3*
2961 Sun 2, running SunOS 4 m68000-*-sunos4*
2962 Motorola 680x0 running LynxOS m68*-*-lynxos*
2963 AT&T 3b1/Unix pc m68*-att-*
2964 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2965 decstation mips-dec-* mips-little-*
2966 riscos mips-*-riscos* mips-*-sysv*
2967 sonymips mips-sony-*
2968 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2970 * REMOVED configurations and files
2972 SGI Irix-4.x mips-sgi-irix4 or iris4
2973 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2974 Z8000 simulator z8k-zilog-none or z8ksim
2975 Matsushita MN10200 w/simulator mn10200-*-*
2976 H8/500 simulator h8500-hitachi-hms or h8500hms
2977 HP/PA running BSD hppa*-*-bsd*
2978 HP/PA running OSF/1 hppa*-*-osf*
2979 HP/PA Pro target hppa*-*-pro*
2980 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2981 386BSD i[3456]86-*-bsd*
2982 Sequent family i[3456]86-sequent-sysv4*
2983 i[3456]86-sequent-sysv*
2984 i[3456]86-sequent-bsd*
2985 SPARC running LynxOS sparc-*-lynxos*
2986 SPARC running SunOS 4 sparc-*-sunos4*
2987 Tsqware Sparclet sparclet-*-*
2988 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2990 *** Changes in GDB 6.0:
2994 Support for debugging the Objective-C programming language has been
2995 integrated into GDB.
2997 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2999 DWARF 2's Call Frame Information makes available compiler generated
3000 information that more exactly describes the program's run-time stack.
3001 By using this information, GDB is able to provide more robust stack
3004 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3005 have been updated to use a new backtrace mechanism which includes
3006 DWARF 2 CFI support.
3010 GDB's remote protocol has been extended to include support for hosted
3011 file I/O (where the remote target uses GDB's file system). See GDB's
3012 remote protocol documentation for details.
3014 * All targets using the new architecture framework.
3016 All of GDB's targets have been updated to use the new internal
3017 architecture framework. The way is now open for future GDB releases
3018 to include cross-architecture native debugging support (i386 on amd64,
3021 * GNU/Linux's Thread Local Storage (TLS)
3023 GDB now includes support for for the GNU/Linux implementation of
3024 per-thread variables.
3026 * GNU/Linux's Native POSIX Thread Library (NPTL)
3028 GDB's thread code has been updated to work with either the new
3029 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3031 * Separate debug info.
3033 GDB, in conjunction with BINUTILS, now supports a mechanism for
3034 automatically loading debug information from a separate file. Instead
3035 of shipping full debug and non-debug versions of system libraries,
3036 system integrators can now instead ship just the stripped libraries
3037 and optional debug files.
3039 * DWARF 2 Location Expressions
3041 DWARF 2 Location Expressions allow the compiler to more completely
3042 describe the location of variables (even in optimized code) to the
3045 GDB now includes preliminary support for location expressions (support
3046 for DW_OP_piece is still missing).
3050 A number of long standing bugs that caused GDB to die while starting a
3051 Java application have been fixed. GDB's Java support is now
3052 considered "useable".
3054 * GNU/Linux support for fork, vfork, and exec.
3056 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3057 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3060 * GDB supports logging output to a file
3062 There are two new commands, "set logging" and "show logging", which can be
3063 used to capture GDB's output to a file.
3065 * The meaning of "detach" has changed for gdbserver
3067 The "detach" command will now resume the application, as documented. To
3068 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3071 * d10v, m68hc11 `regs' command deprecated
3073 The `info registers' command has been updated so that it displays the
3074 registers using a format identical to the old `regs' command.
3078 A new command, "maint set profile on/off", has been added. This command can
3079 be used to enable or disable profiling while running GDB, to profile a
3080 session or a set of commands. In addition there is a new configure switch,
3081 "--enable-profiling", which will cause GDB to be compiled with profiling
3082 data, for more informative profiling results.
3084 * Default MI syntax changed to "mi2".
3086 The default MI (machine interface) syntax, enabled by the command line
3087 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3088 "mi1", can be enabled by specifying the option "-i=mi1".
3090 Support for the original "mi0" syntax (included in GDB 5.0) has been
3093 Fix for gdb/192: removed extraneous space when displaying frame level.
3094 Fix for gdb/672: update changelist is now output in mi list format.
3095 Fix for gdb/702: a -var-assign that updates the value now shows up
3096 in a subsequent -var-update.
3098 * New native configurations.
3100 FreeBSD/amd64 x86_64-*-freebsd*
3102 * Multi-arched targets.
3104 HP/PA HPUX11 hppa*-*-hpux*
3105 Renesas M32R/D w/simulator m32r-*-elf*
3107 * OBSOLETE configurations and files
3109 Configurations that have been declared obsolete in this release have
3110 been commented out. Unless there is activity to revive these
3111 configurations, the next release of GDB will have their sources
3112 permanently REMOVED.
3114 Z8000 simulator z8k-zilog-none or z8ksim
3115 Matsushita MN10200 w/simulator mn10200-*-*
3116 H8/500 simulator h8500-hitachi-hms or h8500hms
3117 HP/PA running BSD hppa*-*-bsd*
3118 HP/PA running OSF/1 hppa*-*-osf*
3119 HP/PA Pro target hppa*-*-pro*
3120 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3121 Sequent family i[3456]86-sequent-sysv4*
3122 i[3456]86-sequent-sysv*
3123 i[3456]86-sequent-bsd*
3124 Tsqware Sparclet sparclet-*-*
3125 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3127 * REMOVED configurations and files
3130 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3131 IBM AIX PS/2 i[3456]86-*-aix
3132 i386 running Mach 3.0 i[3456]86-*-mach3*
3133 i386 running Mach i[3456]86-*-mach*
3134 i386 running OSF/1 i[3456]86-*osf1mk*
3135 HP/Apollo 68k Family m68*-apollo*-sysv*,
3137 m68*-hp-bsd*, m68*-hp-hpux*
3138 Argonaut Risc Chip (ARC) arc-*-*
3139 Mitsubishi D30V d30v-*-*
3140 Fujitsu FR30 fr30-*-elf*
3141 OS/9000 i[34]86-*-os9k
3142 I960 with MON960 i960-*-coff
3144 * MIPS $fp behavior changed
3146 The convenience variable $fp, for the MIPS, now consistently returns
3147 the address of the current frame's base. Previously, depending on the
3148 context, $fp could refer to either $sp or the current frame's base
3149 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3150 The GNU Source-Level Debugger''.
3152 *** Changes in GDB 5.3:
3154 * GNU/Linux shared library multi-threaded performance improved.
3156 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3157 `/proc', in preference to `ptrace' for memory reads. This may result
3158 in an improvement in the start-up time of multi-threaded, shared
3159 library applications when run under GDB. One GDB user writes: ``loads
3160 shared libs like mad''.
3162 * ``gdbserver'' now supports multi-threaded applications on some targets
3164 Support for debugging multi-threaded applications which use
3165 the GNU/Linux LinuxThreads package has been added for
3166 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3167 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3169 * GDB now supports C/C++ preprocessor macros.
3171 GDB now expands preprocessor macro invocations in C/C++ expressions,
3172 and provides various commands for showing macro definitions and how
3175 The new command `macro expand EXPRESSION' expands any macro
3176 invocations in expression, and shows the result.
3178 The new command `show macro MACRO-NAME' shows the definition of the
3179 macro named MACRO-NAME, and where it was defined.
3181 Most compilers don't include information about macros in the debugging
3182 information by default. In GCC 3.1, for example, you need to compile
3183 your program with the options `-gdwarf-2 -g3'. If the macro
3184 information is present in the executable, GDB will read it.
3186 * Multi-arched targets.
3188 DEC Alpha (partial) alpha*-*-*
3189 DEC VAX (partial) vax-*-*
3191 National Semiconductor NS32000 (partial) ns32k-*-*
3192 Motorola 68000 (partial) m68k-*-*
3193 Motorola MCORE mcore-*-*
3197 Fujitsu FRV architecture added by Red Hat frv*-*-*
3200 * New native configurations
3202 Alpha NetBSD alpha*-*-netbsd*
3203 SH NetBSD sh*-*-netbsdelf*
3204 MIPS NetBSD mips*-*-netbsd*
3205 UltraSPARC NetBSD sparc64-*-netbsd*
3207 * OBSOLETE configurations and files
3209 Configurations that have been declared obsolete in this release have
3210 been commented out. Unless there is activity to revive these
3211 configurations, the next release of GDB will have their sources
3212 permanently REMOVED.
3214 Mitsubishi D30V d30v-*-*
3215 OS/9000 i[34]86-*-os9k
3216 IBM AIX PS/2 i[3456]86-*-aix
3217 Fujitsu FR30 fr30-*-elf*
3218 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3219 Argonaut Risc Chip (ARC) arc-*-*
3220 i386 running Mach 3.0 i[3456]86-*-mach3*
3221 i386 running Mach i[3456]86-*-mach*
3222 i386 running OSF/1 i[3456]86-*osf1mk*
3223 HP/Apollo 68k Family m68*-apollo*-sysv*,
3225 m68*-hp-bsd*, m68*-hp-hpux*
3226 I960 with MON960 i960-*-coff
3228 * OBSOLETE languages
3230 CHILL, a Pascal like language used by telecommunications companies.
3232 * REMOVED configurations and files
3234 AMD 29k family via UDI a29k-amd-udi, udi29k
3235 A29K VxWorks a29k-*-vxworks
3236 AMD 29000 embedded, using EBMON a29k-none-none
3237 AMD 29000 embedded with COFF a29k-none-coff
3238 AMD 29000 embedded with a.out a29k-none-aout
3240 testsuite/gdb.hp/gdb.threads-hp/ directory
3242 * New command "set max-user-call-depth <nnn>"
3244 This command allows the user to limit the call depth of user-defined
3245 commands. The default is 1024.
3247 * Changes in FreeBSD/i386 native debugging.
3249 Support for the "generate-core-file" has been added.
3251 * New commands "dump", "append", and "restore".
3253 These commands allow data to be copied from target memory
3254 to a bfd-format or binary file (dump and append), and back
3255 from a file into memory (restore).
3257 * Improved "next/step" support on multi-processor Alpha Tru64.
3259 The previous single-step mechanism could cause unpredictable problems,
3260 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3261 of a software single-step mechanism prevents this.
3263 *** Changes in GDB 5.2.1:
3271 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3272 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3273 Fix, by Joel Brobecker imported from mainline.
3275 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3276 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3277 Fix, by Fred Fish, imported from mainline.
3279 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3280 Surprisingly enough, it works now.
3281 By Michal Ludvig, imported from mainline.
3283 i386 hardware watchpoint support:
3284 avoid misses on second run for some targets.
3285 By Pierre Muller, imported from mainline.
3287 *** Changes in GDB 5.2:
3289 * New command "set trust-readonly-sections on[off]".
3291 This command is a hint that tells gdb that read-only sections
3292 really are read-only (ie. that their contents will not change).
3293 In this mode, gdb will go to the object file rather than the
3294 target to read memory from read-only sections (such as ".text").
3295 This can be a significant performance improvement on some
3296 (notably embedded) targets.
3298 * New command "generate-core-file" (or "gcore").
3300 This new gdb command allows the user to drop a core file of the child
3301 process state at any time. So far it's been implemented only for
3302 GNU/Linux and Solaris, but should be relatively easily ported to other
3303 hosts. Argument is core file name (defaults to core.<pid>).
3305 * New command line option
3307 GDB now accepts --pid or -p followed by a process id.
3309 * Change in command line behavior -- corefiles vs. process ids.
3311 There is a subtle behavior in the way in which GDB handles
3312 command line arguments. The first non-flag argument is always
3313 a program to debug, but the second non-flag argument may either
3314 be a corefile or a process id. Previously, GDB would attempt to
3315 open the second argument as a corefile, and if that failed, would
3316 issue a superfluous error message and then attempt to attach it as
3317 a process. Now, if the second argument begins with a non-digit,
3318 it will be treated as a corefile. If it begins with a digit,
3319 GDB will attempt to attach it as a process, and if no such process
3320 is found, will then attempt to open it as a corefile.
3322 * Changes in ARM configurations.
3324 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3325 configuration is fully multi-arch.
3327 * New native configurations
3329 ARM NetBSD arm*-*-netbsd*
3330 x86 OpenBSD i[3456]86-*-openbsd*
3331 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3332 Sparc64 running FreeBSD sparc64-*-freebsd*
3336 Sanyo XStormy16 xstormy16-elf
3338 * OBSOLETE configurations and files
3340 Configurations that have been declared obsolete in this release have
3341 been commented out. Unless there is activity to revive these
3342 configurations, the next release of GDB will have their sources
3343 permanently REMOVED.
3345 AMD 29k family via UDI a29k-amd-udi, udi29k
3346 A29K VxWorks a29k-*-vxworks
3347 AMD 29000 embedded, using EBMON a29k-none-none
3348 AMD 29000 embedded with COFF a29k-none-coff
3349 AMD 29000 embedded with a.out a29k-none-aout
3351 testsuite/gdb.hp/gdb.threads-hp/ directory
3353 * REMOVED configurations and files
3355 TI TMS320C80 tic80-*-*
3357 PowerPC Solaris powerpcle-*-solaris*
3358 PowerPC Windows NT powerpcle-*-cygwin32
3359 PowerPC Netware powerpc-*-netware*
3360 Harris/CXUX m88k m88*-harris-cxux*
3361 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3362 ns32k-utek-sysv* ns32k-utek-*
3363 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3364 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3365 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3366 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3367 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3369 * Changes to command line processing
3371 The new `--args' feature can be used to specify command-line arguments
3372 for the inferior from gdb's command line.
3374 * Changes to key bindings
3376 There is a new `operate-and-get-next' function bound to `C-o'.
3378 *** Changes in GDB 5.1.1
3380 Fix compile problem on DJGPP.
3382 Fix a problem with floating-point registers on the i386 being
3385 Fix to stop GDB crashing on .debug_str debug info.
3387 Numerous documentation fixes.
3389 Numerous testsuite fixes.
3391 *** Changes in GDB 5.1:
3393 * New native configurations
3395 Alpha FreeBSD alpha*-*-freebsd*
3396 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3397 MIPS GNU/Linux mips*-*-linux*
3398 MIPS SGI Irix 6.x mips*-sgi-irix6*
3399 ia64 AIX ia64-*-aix*
3400 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3404 Motorola 68HC11 and 68HC12 m68hc11-elf
3406 UltraSparc running GNU/Linux sparc64-*-linux*
3408 * OBSOLETE configurations and files
3410 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3411 Harris/CXUX m88k m88*-harris-cxux*
3412 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3413 ns32k-utek-sysv* ns32k-utek-*
3414 TI TMS320C80 tic80-*-*
3416 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3417 PowerPC Solaris powerpcle-*-solaris*
3418 PowerPC Windows NT powerpcle-*-cygwin32
3419 PowerPC Netware powerpc-*-netware*
3420 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3421 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3422 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3423 Apple Macintosh (MPW) host N/A
3425 stuff.c (Program to stuff files into a specially prepared space in kdb)
3426 kdb-start.c (Main loop for the standalone kernel debugger)
3428 Configurations that have been declared obsolete in this release have
3429 been commented out. Unless there is activity to revive these
3430 configurations, the next release of GDB will have their sources
3431 permanently REMOVED.
3433 * REMOVED configurations and files
3435 Altos 3068 m68*-altos-*
3436 Convex c1-*-*, c2-*-*
3438 ARM RISCix arm-*-* (as host)
3442 * GDB has been converted to ISO C.
3444 GDB's source code has been converted to ISO C. In particular, the
3445 sources are fully protoized, and rely on standard headers being
3450 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3452 * The MI enabled by default.
3454 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3455 revised and enabled by default. Packages which use GDB as a debugging
3456 engine behind a UI or another front end are encouraged to switch to
3457 using the GDB/MI interface, instead of the old annotations interface
3458 which is now deprecated.
3460 * Support for debugging Pascal programs.
3462 GDB now includes support for debugging Pascal programs. The following
3463 main features are supported:
3465 - Pascal-specific data types such as sets;
3467 - automatic recognition of Pascal sources based on file-name
3470 - Pascal-style display of data types, variables, and functions;
3472 - a Pascal expression parser.
3474 However, some important features are not yet supported.
3476 - Pascal string operations are not supported at all;
3478 - there are some problems with boolean types;
3480 - Pascal type hexadecimal constants are not supported
3481 because they conflict with the internal variables format;
3483 - support for Pascal objects and classes is not full yet;
3485 - unlike Pascal, GDB is case-sensitive for symbol names.
3487 * Changes in completion.
3489 Commands such as `shell', `run' and `set args', which pass arguments
3490 to inferior programs, now complete on file names, similar to what
3491 users expect at the shell prompt.
3493 Commands which accept locations, such as `disassemble', `print',
3494 `breakpoint', `until', etc. now complete on filenames as well as
3495 program symbols. Thus, if you type "break foob TAB", and the source
3496 files linked into the programs include `foobar.c', that file name will
3497 be one of the candidates for completion. However, file names are not
3498 considered for completion after you typed a colon that delimits a file
3499 name from a name of a function in that file, as in "break foo.c:bar".
3501 `set demangle-style' completes on available demangling styles.
3503 * New platform-independent commands:
3505 It is now possible to define a post-hook for a command as well as a
3506 hook that runs before the command. For more details, see the
3507 documentation of `hookpost' in the GDB manual.
3509 * Changes in GNU/Linux native debugging.
3511 Support for debugging multi-threaded programs has been completely
3512 revised for all platforms except m68k and sparc. You can now debug as
3513 many threads as your system allows you to have.
3515 Attach/detach is supported for multi-threaded programs.
3517 Support for SSE registers was added for x86. This doesn't work for
3518 multi-threaded programs though.
3520 * Changes in MIPS configurations.
3522 Multi-arch support is enabled for all MIPS configurations.
3524 GDB can now be built as native debugger on SGI Irix 6.x systems for
3525 debugging n32 executables. (Debugging 64-bit executables is not yet
3528 * Unified support for hardware watchpoints in all x86 configurations.
3530 Most (if not all) native x86 configurations support hardware-assisted
3531 breakpoints and watchpoints in a unified manner. This support
3532 implements debug register sharing between watchpoints, which allows to
3533 put a virtually infinite number of watchpoints on the same address,
3534 and also supports watching regions up to 16 bytes with several debug
3537 The new maintenance command `maintenance show-debug-regs' toggles
3538 debugging print-outs in functions that insert, remove, and test
3539 watchpoints and hardware breakpoints.
3541 * Changes in the DJGPP native configuration.
3543 New command ``info dos sysinfo'' displays assorted information about
3544 the CPU, OS, memory, and DPMI server.
3546 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3547 display information about segment descriptors stored in GDT, LDT, and
3550 New commands ``info dos pde'' and ``info dos pte'' display entries
3551 from Page Directory and Page Tables (for now works with CWSDPMI only).
3552 New command ``info dos address-pte'' displays the Page Table entry for
3553 a given linear address.
3555 GDB can now pass command lines longer than 126 characters to the
3556 program being debugged (requires an update to the libdbg.a library
3557 which is part of the DJGPP development kit).
3559 DWARF2 debug info is now supported.
3561 It is now possible to `step' and `next' through calls to `longjmp'.
3563 * Changes in documentation.
3565 All GDB documentation was converted to GFDL, the GNU Free
3566 Documentation License.
3568 Tracepoints-related commands are now fully documented in the GDB
3571 TUI, the Text-mode User Interface, is now documented in the manual.
3573 Tracepoints-related commands are now fully documented in the GDB
3576 The "GDB Internals" manual now has an index. It also includes
3577 documentation of `ui_out' functions, GDB coding standards, x86
3578 hardware watchpoints, and memory region attributes.
3580 * GDB's version number moved to ``version.in''
3582 The Makefile variable VERSION has been replaced by the file
3583 ``version.in''. People creating GDB distributions should update the
3584 contents of this file.
3588 GUD support is now a standard part of the EMACS distribution.
3590 *** Changes in GDB 5.0:
3592 * Improved support for debugging FP programs on x86 targets
3594 Unified and much-improved support for debugging floating-point
3595 programs on all x86 targets. In particular, ``info float'' now
3596 displays the FP registers in the same format on all x86 targets, with
3597 greater level of detail.
3599 * Improvements and bugfixes in hardware-assisted watchpoints
3601 It is now possible to watch array elements, struct members, and
3602 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3603 on x86 targets no longer erroneously trigger when the address is
3606 * Improvements in the native DJGPP version of GDB
3608 The distribution now includes all the scripts and auxiliary files
3609 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3610 machines ``out of the box''.
3612 The DJGPP version can now debug programs that use signals. It is
3613 possible to catch signals that happened in the debuggee, deliver
3614 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3615 would kill the program being debugged.) Programs that hook hardware
3616 interrupts (keyboard, timer, etc.) can also be debugged.
3618 It is now possible to debug DJGPP programs that redirect their
3619 standard handles or switch them to raw (as opposed to cooked) mode, or
3620 even close them. The command ``run < foo > bar'' works as expected,
3621 and ``info terminal'' reports useful information about the debuggee's
3622 terminal, including raw/cooked mode, redirection, etc.
3624 The DJGPP version now uses termios functions for console I/O, which
3625 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3628 DOS-style file names with drive letters are now fully supported by
3631 It is now possible to debug DJGPP programs that switch their working
3632 directory. It is also possible to rerun the debuggee any number of
3633 times without restarting GDB; thus, you can use the same setup,
3634 breakpoints, etc. for many debugging sessions.
3636 * New native configurations
3638 ARM GNU/Linux arm*-*-linux*
3639 PowerPC GNU/Linux powerpc-*-linux*
3643 Motorola MCore mcore-*-*
3644 x86 VxWorks i[3456]86-*-vxworks*
3645 PowerPC VxWorks powerpc-*-vxworks*
3646 TI TMS320C80 tic80-*-*
3648 * OBSOLETE configurations
3650 Altos 3068 m68*-altos-*
3651 Convex c1-*-*, c2-*-*
3653 ARM RISCix arm-*-* (as host)
3656 Configurations that have been declared obsolete will be commented out,
3657 but the code will be left in place. If there is no activity to revive
3658 these configurations before the next release of GDB, the sources will
3659 be permanently REMOVED.
3661 * Gould support removed
3663 Support for the Gould PowerNode and NP1 has been removed.
3665 * New features for SVR4
3667 On SVR4 native platforms (such as Solaris), if you attach to a process
3668 without first loading a symbol file, GDB will now attempt to locate and
3669 load symbols from the running process's executable file.
3671 * Many C++ enhancements
3673 C++ support has been greatly improved. Overload resolution now works properly
3674 in almost all cases. RTTI support is on the way.
3676 * Remote targets can connect to a sub-program
3678 A popen(3) style serial-device has been added. This device starts a
3679 sub-process (such as a stand-alone simulator) and then communicates
3680 with that. The sub-program to run is specified using the syntax
3681 ``|<program> <args>'' vis:
3683 (gdb) set remotedebug 1
3684 (gdb) target extended-remote |mn10300-elf-sim program-args
3686 * MIPS 64 remote protocol
3688 A long standing bug in the mips64 remote protocol where by GDB
3689 expected certain 32 bit registers (ex SR) to be transfered as 32
3690 instead of 64 bits has been fixed.
3692 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3693 added to provide backward compatibility with older versions of GDB.
3695 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3697 The command ``set remotebinarydownload'' command has been replaced by
3698 ``set remote X-packet''. Other commands in ``set remote'' family
3699 include ``set remote P-packet''.
3701 * Breakpoint commands accept ranges.
3703 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3704 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3705 ``tracepoint passcount'' also accepts a range of tracepoints.
3707 * ``apropos'' command added.
3709 The ``apropos'' command searches through command names and
3710 documentation strings, printing out matches, making it much easier to
3711 try to find a command that does what you are looking for.
3715 A new machine oriented interface (MI) has been added to GDB. This
3716 interface is designed for debug environments running GDB as a separate
3717 process. This is part of the long term libGDB project. See the
3718 "GDB/MI" chapter of the GDB manual for further information. It can be
3719 enabled by configuring with:
3721 .../configure --enable-gdbmi
3723 *** Changes in GDB-4.18:
3725 * New native configurations
3727 HP-UX 10.20 hppa*-*-hpux10.20
3728 HP-UX 11.x hppa*-*-hpux11.0*
3729 M68K GNU/Linux m68*-*-linux*
3733 Fujitsu FR30 fr30-*-elf*
3734 Intel StrongARM strongarm-*-*
3735 Mitsubishi D30V d30v-*-*
3737 * OBSOLETE configurations
3739 Gould PowerNode, NP1 np1-*-*, pn-*-*
3741 Configurations that have been declared obsolete will be commented out,
3742 but the code will be left in place. If there is no activity to revive
3743 these configurations before the next release of GDB, the sources will
3744 be permanently REMOVED.
3748 As a compatibility experiment, GDB's source files buildsym.h and
3749 buildsym.c have been converted to pure standard C, no longer
3750 containing any K&R compatibility code. We believe that all systems in
3751 use today either come with a standard C compiler, or have a GCC port
3752 available. If this is not true, please report the affected
3753 configuration to bug-gdb@gnu.org immediately. See the README file for
3754 information about getting a standard C compiler if you don't have one
3759 GDB now uses readline 2.2.
3761 * set extension-language
3763 You can now control the mapping between filename extensions and source
3764 languages by using the `set extension-language' command. For instance,
3765 you can ask GDB to treat .c files as C++ by saying
3766 set extension-language .c c++
3767 The command `info extensions' lists all of the recognized extensions
3768 and their associated languages.
3770 * Setting processor type for PowerPC and RS/6000
3772 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3773 you can use the `set processor' command to specify what variant of the
3774 PowerPC family you are debugging. The command
3778 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3779 following PowerPC and RS6000 variants:
3781 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3782 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3784 403GC IBM PowerPC 403GC
3785 505 Motorola PowerPC 505
3786 860 Motorola PowerPC 860 or 850
3787 601 Motorola PowerPC 601
3788 602 Motorola PowerPC 602
3789 603 Motorola/IBM PowerPC 603 or 603e
3790 604 Motorola PowerPC 604 or 604e
3791 750 Motorola/IBM PowerPC 750 or 750
3793 At the moment, this command just tells GDB what to name the
3794 special-purpose processor registers. Since almost all the affected
3795 registers are inaccessible to user-level programs, this command is
3796 only useful for remote debugging in its present form.
3800 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3801 more extensive support for HP-UX. Added features include shared
3802 library support, kernel threads and hardware watchpoints for 11.00,
3803 support for HP's ANSI C and C++ compilers, and a compatibility mode
3804 for xdb and dbx commands.
3808 HP's donation includes the new concept of catchpoints, which is a
3809 generalization of the old catch command. On HP-UX, it is now possible
3810 to catch exec, fork, and vfork, as well as library loading.
3812 This means that the existing catch command has changed; its first
3813 argument now specifies the type of catch to be set up. See the
3814 output of "help catch" for a list of catchpoint types.
3816 * Debugging across forks
3818 On HP-UX, you can choose which process to debug when a fork() happens
3823 HP has donated a curses-based terminal user interface (TUI). To get
3824 it, build with --enable-tui. Although this can be enabled for any
3825 configuration, at present it only works for native HP debugging.
3827 * GDB remote protocol additions
3829 A new protocol packet 'X' that writes binary data is now available.
3830 Default behavior is to try 'X', then drop back to 'M' if the stub
3831 fails to respond. The settable variable `remotebinarydownload'
3832 allows explicit control over the use of 'X'.
3834 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3835 full 64-bit address. The command
3837 set remoteaddresssize 32
3839 can be used to revert to the old behaviour. For existing remote stubs
3840 the change should not be noticed, as the additional address information
3843 In order to assist in debugging stubs, you may use the maintenance
3844 command `packet' to send any text string to the stub. For instance,
3846 maint packet heythere
3848 sends the packet "$heythere#<checksum>". Note that it is very easy to
3849 disrupt a debugging session by sending the wrong packet at the wrong
3852 The compare-sections command allows you to compare section data on the
3853 target to what is in the executable file without uploading or
3854 downloading, by comparing CRC checksums.
3856 * Tracing can collect general expressions
3858 You may now collect general expressions at tracepoints. This requires
3859 further additions to the target-side stub; see tracepoint.c and
3860 doc/agentexpr.texi for further details.
3862 * mask-address variable for Mips
3864 For Mips targets, you may control the zeroing of the upper 32 bits of
3865 a 64-bit address by entering `set mask-address on'. This is mainly
3866 of interest to users of embedded R4xxx and R5xxx processors.
3868 * Higher serial baud rates
3870 GDB's serial code now allows you to specify baud rates 57600, 115200,
3871 230400, and 460800 baud. (Note that your host system may not be able
3872 to achieve all of these rates.)
3876 The i960 configuration now includes an initial implementation of a
3877 builtin simulator, contributed by Jim Wilson.
3880 *** Changes in GDB-4.17:
3882 * New native configurations
3884 Alpha GNU/Linux alpha*-*-linux*
3885 Unixware 2.x i[3456]86-unixware2*
3886 Irix 6.x mips*-sgi-irix6*
3887 PowerPC GNU/Linux powerpc-*-linux*
3888 PowerPC Solaris powerpcle-*-solaris*
3889 Sparc GNU/Linux sparc-*-linux*
3890 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3894 Argonaut Risc Chip (ARC) arc-*-*
3895 Hitachi H8/300S h8300*-*-*
3896 Matsushita MN10200 w/simulator mn10200-*-*
3897 Matsushita MN10300 w/simulator mn10300-*-*
3898 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3899 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3900 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3901 Mitsubishi D10V w/simulator d10v-*-*
3902 Mitsubishi M32R/D w/simulator m32r-*-elf*
3903 Tsqware Sparclet sparclet-*-*
3904 NEC V850 w/simulator v850-*-*
3906 * New debugging protocols
3908 ARM with RDI protocol arm*-*-*
3909 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3910 DDB and LSI variants of PMON protocol mips*-*-*
3911 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3912 PowerPC with SDS protocol powerpc{,le}-*-eabi
3913 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3917 All configurations can now understand and use the DWARF 2 debugging
3918 format. The choice is automatic, if the symbol file contains DWARF 2
3923 GDB now includes basic Java language support. This support is
3924 only useful with Java compilers that produce native machine code.
3926 * solib-absolute-prefix and solib-search-path
3928 For SunOS and SVR4 shared libraries, you may now set the prefix for
3929 loading absolute shared library symbol files, and the search path for
3930 locating non-absolute shared library symbol files.
3932 * Live range splitting
3934 GDB can now effectively debug code for which GCC has performed live
3935 range splitting as part of its optimization. See gdb/doc/LRS for
3936 more details on the expected format of the stabs information.
3940 GDB's support for the GNU Hurd, including thread debugging, has been
3941 updated to work with current versions of the Hurd.
3945 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3946 instruction set. ARM GDB automatically detects when Thumb
3947 instructions are in use, and adjusts disassembly and backtracing
3952 GDB's MIPS target configurations now handle the MIP16 16-bit
3957 GDB now includes support for overlays; if an executable has been
3958 linked such that multiple sections are based at the same address, GDB
3959 will decide which section to use for symbolic info. You can choose to
3960 control the decision manually, using overlay commands, or implement
3961 additional target-side support and use "overlay load-target" to bring
3962 in the overlay mapping. Do "help overlay" for more detail.
3966 The command "info symbol <address>" displays information about
3967 the symbol at the specified address.
3971 The standard remote protocol now includes an extension that allows
3972 asynchronous collection and display of trace data. This requires
3973 extensive support in the target-side debugging stub. Tracing mode
3974 includes a new interaction mode in GDB and new commands: see the
3975 file tracepoint.c for more details.
3979 Configurations for embedded MIPS now include a simulator contributed
3980 by Cygnus Solutions. The simulator supports the instruction sets
3981 of most MIPS variants.
3985 Sparc configurations may now include the ERC32 simulator contributed
3986 by the European Space Agency. The simulator is not built into
3987 Sparc targets by default; configure with --enable-sim to include it.
3991 For target configurations that may include multiple variants of a
3992 basic architecture (such as MIPS and SH), you may now set the
3993 architecture explicitly. "set arch" sets, "info arch" lists
3994 the possible architectures.
3996 *** Changes in GDB-4.16:
3998 * New native configurations
4000 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4001 M68K NetBSD m68k-*-netbsd*
4002 PowerPC AIX 4.x powerpc-*-aix*
4003 PowerPC MacOS powerpc-*-macos*
4004 PowerPC Windows NT powerpcle-*-cygwin32
4005 RS/6000 AIX 4.x rs6000-*-aix4*
4009 ARM with RDP protocol arm-*-*
4010 I960 with MON960 i960-*-coff
4011 MIPS VxWorks mips*-*-vxworks*
4012 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4013 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4015 Matra Sparclet sparclet-*-*
4019 The powerpc-eabi configuration now includes the PSIM simulator,
4020 contributed by Andrew Cagney, with assistance from Mike Meissner.
4021 PSIM is a very elaborate model of the PowerPC, including not only
4022 basic instruction set execution, but also details of execution unit
4023 performance and I/O hardware. See sim/ppc/README for more details.
4027 GDB now works with Solaris 2.5.
4029 * Windows 95/NT native
4031 GDB will now work as a native debugger on Windows 95 and Windows NT.
4032 To build it from source, you must use the "gnu-win32" environment,
4033 which uses a DLL to emulate enough of Unix to run the GNU tools.
4034 Further information, binaries, and sources are available at
4035 ftp.cygnus.com, under pub/gnu-win32.
4037 * dont-repeat command
4039 If a user-defined command includes the command `dont-repeat', then the
4040 command will not be repeated if the user just types return. This is
4041 useful if the command is time-consuming to run, so that accidental
4042 extra keystrokes don't run the same command many times.
4044 * Send break instead of ^C
4046 The standard remote protocol now includes an option to send a break
4047 rather than a ^C to the target in order to interrupt it. By default,
4048 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4050 * Remote protocol timeout
4052 The standard remote protocol includes a new variable `remotetimeout'
4053 that allows you to set the number of seconds before GDB gives up trying
4054 to read from the target. The default value is 2.
4056 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4058 By default GDB will automatically keep track of objects as they are
4059 loaded and unloaded by the dynamic linker. By using the command `set
4060 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4061 when shared library events occur, thus allowing you to set breakpoints
4062 in shared libraries which are explicitly loaded by the inferior.
4064 Note this feature does not work on hpux8. On hpux9 you must link
4065 /usr/lib/end.o into your program. This feature should work
4066 automatically on hpux10.
4068 * Irix 5.x hardware watchpoint support
4070 Irix 5 configurations now support the use of hardware watchpoints.
4072 * Mips protocol "SYN garbage limit"
4074 When debugging a Mips target using the `target mips' protocol, you
4075 may set the number of characters that GDB will ignore by setting
4076 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4077 every character. The default value is 1050.
4079 * Recording and replaying remote debug sessions
4081 If you set `remotelogfile' to the name of a file, gdb will write to it
4082 a recording of a remote debug session. This recording may then be
4083 replayed back to gdb using "gdbreplay". See gdbserver/README for
4084 details. This is useful when you have a problem with GDB while doing
4085 remote debugging; you can make a recording of the session and send it
4086 to someone else, who can then recreate the problem.
4088 * Speedups for remote debugging
4090 GDB includes speedups for downloading and stepping MIPS systems using
4091 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4092 and more efficient S-record downloading.
4094 * Memory use reductions and statistics collection
4096 GDB now uses less memory and reports statistics about memory usage.
4097 Try the `maint print statistics' command, for example.
4099 *** Changes in GDB-4.15:
4101 * Psymtabs for XCOFF
4103 The symbol reader for AIX GDB now uses partial symbol tables. This
4104 can greatly improve startup time, especially for large executables.
4106 * Remote targets use caching
4108 Remote targets now use a data cache to speed up communication with the
4109 remote side. The data cache could lead to incorrect results because
4110 it doesn't know about volatile variables, thus making it impossible to
4111 debug targets which use memory mapped I/O devices. `set remotecache
4112 off' turns the the data cache off.
4114 * Remote targets may have threads
4116 The standard remote protocol now includes support for multiple threads
4117 in the target system, using new protocol commands 'H' and 'T'. See
4118 gdb/remote.c for details.
4122 If GDB is configured with `--enable-netrom', then it will include
4123 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4124 acts as though it is a bank of ROM on the target board, but you can
4125 write into it over the network. GDB's support consists only of
4126 support for fast loading into the emulated ROM; to debug, you must use
4127 another protocol, such as standard remote protocol. The usual
4128 sequence is something like
4130 target nrom <netrom-hostname>
4132 target remote <netrom-hostname>:1235
4136 GDB now includes support for the Apple Macintosh, as a host only. It
4137 may be run as either an MPW tool or as a standalone application, and
4138 it can debug through the serial port. All the usual GDB commands are
4139 available, but to the target command, you must supply "serial" as the
4140 device type instead of "/dev/ttyXX". See mpw-README in the main
4141 directory for more information on how to build. The MPW configuration
4142 scripts */mpw-config.in support only a few targets, and only the
4143 mips-idt-ecoff target has been tested.
4147 GDB configuration now uses autoconf. This is not user-visible,
4148 but does simplify configuration and building.
4152 GDB now supports hpux10.
4154 *** Changes in GDB-4.14:
4156 * New native configurations
4158 x86 FreeBSD i[345]86-*-freebsd
4159 x86 NetBSD i[345]86-*-netbsd
4160 NS32k NetBSD ns32k-*-netbsd
4161 Sparc NetBSD sparc-*-netbsd
4165 A29K VxWorks a29k-*-vxworks
4166 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4167 CPU32 EST-300 emulator m68*-*-est*
4168 PowerPC ELF powerpc-*-elf
4171 * Alpha OSF/1 support for procfs
4173 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4174 possible to attach to running processes. As the mounting of the /proc
4175 filesystem is optional on the Alpha, GDB automatically determines
4176 the availability of /proc during startup. This can lead to problems
4177 if /proc is unmounted after GDB has been started.
4179 * Arguments to user-defined commands
4181 User commands may accept up to 10 arguments separated by whitespace.
4182 Arguments are accessed within the user command via $arg0..$arg9. A
4185 print $arg0 + $arg1 + $arg2
4187 To execute the command use:
4190 Defines the command "adder" which prints the sum of its three arguments.
4191 Note the arguments are text substitutions, so they may reference variables,
4192 use complex expressions, or even perform inferior function calls.
4194 * New `if' and `while' commands
4196 This makes it possible to write more sophisticated user-defined
4197 commands. Both commands take a single argument, which is the
4198 expression to evaluate, and must be followed by the commands to
4199 execute, one per line, if the expression is nonzero, the list being
4200 terminated by the word `end'. The `if' command list may include an
4201 `else' word, which causes the following commands to be executed only
4202 if the expression is zero.
4204 * Fortran source language mode
4206 GDB now includes partial support for Fortran 77. It will recognize
4207 Fortran programs and can evaluate a subset of Fortran expressions, but
4208 variables and functions may not be handled correctly. GDB will work
4209 with G77, but does not yet know much about symbols emitted by other
4212 * Better HPUX support
4214 Most debugging facilities now work on dynamic executables for HPPAs
4215 running hpux9 or later. You can attach to running dynamically linked
4216 processes, but by default the dynamic libraries will be read-only, so
4217 for instance you won't be able to put breakpoints in them. To change
4218 that behavior do the following before running the program:
4224 This will cause the libraries to be mapped private and read-write.
4225 To revert to the normal behavior, do this:
4231 You cannot set breakpoints or examine data in the library until after
4232 the library is loaded if the function/data symbols do not have
4235 GDB can now also read debug symbols produced by the HP C compiler on
4236 HPPAs (sorry, no C++, Fortran or 68k support).
4238 * Target byte order now dynamically selectable
4240 You can choose which byte order to use with a target system, via the
4241 commands "set endian big" and "set endian little", and you can see the
4242 current setting by using "show endian". You can also give the command
4243 "set endian auto", in which case GDB will use the byte order
4244 associated with the executable. Currently, only embedded MIPS
4245 configurations support dynamic selection of target byte order.
4247 * New DOS host serial code
4249 This version uses DPMI interrupts to handle buffered I/O, so you
4250 no longer need to run asynctsr when debugging boards connected to
4253 *** Changes in GDB-4.13:
4255 * New "complete" command
4257 This lists all the possible completions for the rest of the line, if it
4258 were to be given as a command itself. This is intended for use by emacs.
4260 * Trailing space optional in prompt
4262 "set prompt" no longer adds a space for you after the prompt you set. This
4263 allows you to set a prompt which ends in a space or one that does not.
4265 * Breakpoint hit counts
4267 "info break" now displays a count of the number of times the breakpoint
4268 has been hit. This is especially useful in conjunction with "ignore"; you
4269 can ignore a large number of breakpoint hits, look at the breakpoint info
4270 to see how many times the breakpoint was hit, then run again, ignoring one
4271 less than that number, and this will get you quickly to the last hit of
4274 * Ability to stop printing at NULL character
4276 "set print null-stop" will cause GDB to stop printing the characters of
4277 an array when the first NULL is encountered. This is useful when large
4278 arrays actually contain only short strings.
4280 * Shared library breakpoints
4282 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4283 breakpoints in shared libraries before the executable is run.
4285 * Hardware watchpoints
4287 There is a new hardware breakpoint for the watch command for sparclite
4288 targets. See gdb/sparclite/hw_breakpoint.note.
4290 Hardware watchpoints are also now supported under GNU/Linux.
4294 Annotations have been added. These are for use with graphical interfaces,
4295 and are still experimental. Currently only gdba.el uses these.
4297 * Improved Irix 5 support
4299 GDB now works properly with Irix 5.2.
4301 * Improved HPPA support
4303 GDB now works properly with the latest GCC and GAS.
4305 * New native configurations
4307 Sequent PTX4 i[34]86-sequent-ptx4
4308 HPPA running OSF/1 hppa*-*-osf*
4309 Atari TT running SVR4 m68*-*-sysv4*
4310 RS/6000 LynxOS rs6000-*-lynxos*
4314 OS/9000 i[34]86-*-os9k
4315 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4318 * Hitachi SH7000 and E7000-PC ICE support
4320 There is now support for communicating with the Hitachi E7000-PC ICE.
4321 This is available automatically when GDB is configured for the SH.
4325 As usual, a variety of small fixes and improvements, both generic
4326 and configuration-specific. See the ChangeLog for more detail.
4328 *** Changes in GDB-4.12:
4330 * Irix 5 is now supported
4334 GDB-4.12 on the HPPA has a number of changes which make it unable
4335 to debug the output from the currently released versions of GCC and
4336 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4337 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4338 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4341 *** Changes in GDB-4.11:
4343 * User visible changes:
4347 The "set remotedebug" option is now consistent between the mips remote
4348 target, remote targets using the gdb-specific protocol, UDI (AMD's
4349 debug protocol for the 29k) and the 88k bug monitor. It is now an
4350 integer specifying a debug level (normally 0 or 1, but 2 means more
4351 debugging info for the mips target).
4353 * DEC Alpha native support
4355 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4356 debug info, but GDB works fairly well with the DEC compiler and should
4357 work with a future GCC release. See the README file for a few
4358 Alpha-specific notes.
4360 * Preliminary thread implementation
4362 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4364 * LynxOS native and target support for 386
4366 This release has been hosted on LynxOS 2.2, and also can be configured
4367 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4370 * Improvements in C++ mangling/demangling.
4372 This release has much better g++ debugging, specifically in name
4373 mangling/demangling, virtual function calls, print virtual table,
4374 call methods, ...etc.
4376 *** Changes in GDB-4.10:
4378 * User visible changes:
4380 Remote debugging using the GDB-specific (`target remote') protocol now
4381 supports the `load' command. This is only useful if you have some
4382 other way of getting the stub to the target system, and you can put it
4383 somewhere in memory where it won't get clobbered by the download.
4385 Filename completion now works.
4387 When run under emacs mode, the "info line" command now causes the
4388 arrow to point to the line specified. Also, "info line" prints
4389 addresses in symbolic form (as well as hex).
4391 All vxworks based targets now support a user settable option, called
4392 vxworks-timeout. This option represents the number of seconds gdb
4393 should wait for responses to rpc's. You might want to use this if
4394 your vxworks target is, perhaps, a slow software simulator or happens
4395 to be on the far side of a thin network line.
4399 This release contains support for using a DEC alpha as a GDB host for
4400 cross debugging. Native alpha debugging is not supported yet.
4403 *** Changes in GDB-4.9:
4407 This is the first GDB release which is accompanied by a matching testsuite.
4408 The testsuite requires installation of dejagnu, which should be available
4409 via ftp from most sites that carry GNU software.
4413 'Cfront' style demangling has had its name changed to 'ARM' style, to
4414 emphasize that it was written from the specifications in the C++ Annotated
4415 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4416 disclaimers, it still generated too much confusion with users attempting to
4417 use gdb with AT&T cfront.
4421 GDB now uses a standard remote interface to a simulator library.
4422 So far, the library contains simulators for the Zilog Z8001/2, the
4423 Hitachi H8/300, H8/500 and Super-H.
4425 * New targets supported
4427 H8/300 simulator h8300-hitachi-hms or h8300hms
4428 H8/500 simulator h8500-hitachi-hms or h8500hms
4429 SH simulator sh-hitachi-hms or sh
4430 Z8000 simulator z8k-zilog-none or z8ksim
4431 IDT MIPS board over serial line mips-idt-ecoff
4433 Cross-debugging to GO32 targets is supported. It requires a custom
4434 version of the i386-stub.c module which is integrated with the
4435 GO32 memory extender.
4437 * New remote protocols
4439 MIPS remote debugging protocol.
4441 * New source languages supported
4443 This version includes preliminary support for Chill, a Pascal like language
4444 used by telecommunications companies. Chill support is also being integrated
4445 into the GNU compiler, but we don't know when it will be publically available.
4448 *** Changes in GDB-4.8:
4450 * HP Precision Architecture supported
4452 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4453 version of this support was available as a set of patches from the
4454 University of Utah. GDB does not support debugging of programs
4455 compiled with the HP compiler, because HP will not document their file
4456 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4457 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4459 Many problems in the preliminary version have been fixed.
4461 * Faster and better demangling
4463 We have improved template demangling and fixed numerous bugs in the GNU style
4464 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4465 character types (wchar_t) are now supported. Demangling of each symbol is now
4466 only done once, and is cached when the symbol table for a file is read in.
4467 This results in a small increase in memory usage for C programs, a moderate
4468 increase in memory usage for C++ programs, and a fantastic speedup in
4471 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4472 from the specifications in the Annotated Reference Manual, which AT&T's
4473 compiler does not actually implement.
4475 * G++ multiple inheritance compiler problem
4477 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4478 inheritance lattices was reworked to properly discover ambiguities. We
4479 recently found an example which causes this new algorithm to fail in a
4480 very subtle way, producing bad debug information for those classes.
4481 The file 'gcc.patch' (in this directory) can be applied to gcc to
4482 circumvent the problem. A future GCC release will contain a complete
4485 The previous G++ debug info problem (mentioned below for the gdb-4.7
4486 release) is fixed in gcc version 2.3.2.
4488 * Improved configure script
4490 The `configure' script will now attempt to guess your system type if
4491 you don't supply a host system type. The old scheme of supplying a
4492 host system triplet is preferable over using this. All the magic is
4493 done in the new `config.guess' script. Examine it for details.
4495 We have also brought our configure script much more in line with the FSF's
4496 version. It now supports the --with-xxx options. In particular,
4497 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4498 The resulting GDB will not be able to read arbitrary object file formats --
4499 only the format ``expected'' to be used on the configured target system.
4500 We hope to make this the default in a future release.
4502 * Documentation improvements
4504 There's new internal documentation on how to modify GDB, and how to
4505 produce clean changes to the code. We implore people to read it
4506 before submitting changes.
4508 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4509 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4510 `info' files are also provided. To build `info' files from scratch,
4511 you will need the latest `makeinfo' release, which will be available in
4512 a future texinfo-X.Y release.
4514 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4515 We're not sure exactly which versions have this problem, but it has
4516 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4517 or better. If that isn't possible, there is a patch in
4518 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4519 around this problem.
4523 GDB now supports array constants that can be used in expressions typed in by
4524 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4525 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4528 The new directory `gdb/sparclite' contains a program that demonstrates
4529 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4531 * New native hosts supported
4533 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4534 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4536 * New targets supported
4538 AMD 29k family via UDI a29k-amd-udi or udi29k
4540 * New file formats supported
4542 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4543 HPUX core files, and SCO 3.2v2 core files.
4547 Attaching to processes now works again; thanks for the many bug reports.
4549 We have also stomped on a bunch of core dumps caused by
4550 printf_filtered("%s") problems.
4552 We eliminated a copyright problem on the rpc and ptrace header files
4553 for VxWorks, which was discovered at the last minute during the 4.7
4554 release. You should now be able to build a VxWorks GDB.
4556 You can now interrupt gdb while an attached process is running. This
4557 will cause the attached process to stop, and give control back to GDB.
4559 We fixed problems caused by using too many file descriptors
4560 for reading symbols from object files and libraries. This was
4561 especially a problem for programs that used many (~100) shared
4564 The `step' command now only enters a subroutine if there is line number
4565 information for the subroutine. Otherwise it acts like the `next'
4566 command. Previously, `step' would enter subroutines if there was
4567 any debugging information about the routine. This avoids problems
4568 when using `cc -g1' on MIPS machines.
4570 * Internal improvements
4572 GDB's internal interfaces have been improved to make it easier to support
4573 debugging of multiple languages in the future.
4575 GDB now uses a common structure for symbol information internally.
4576 Minimal symbols (derived from linkage symbols in object files), partial
4577 symbols (from a quick scan of debug information), and full symbols
4578 contain a common subset of information, making it easier to write
4579 shared code that handles any of them.
4581 * New command line options
4583 We now accept --silent as an alias for --quiet.
4587 The memory-mapped-malloc library is now licensed under the GNU Library
4588 General Public License.
4590 *** Changes in GDB-4.7:
4592 * Host/native/target split
4594 GDB has had some major internal surgery to untangle the support for
4595 hosts and remote targets. Now, when you configure GDB for a remote
4596 target, it will no longer load in all of the support for debugging
4597 local programs on the host. When fully completed and tested, this will
4598 ensure that arbitrary host/target combinations are possible.
4600 The primary conceptual shift is to separate the non-portable code in
4601 GDB into three categories. Host specific code is required any time GDB
4602 is compiled on that host, regardless of the target. Target specific
4603 code relates to the peculiarities of the target, but can be compiled on
4604 any host. Native specific code is everything else: it can only be
4605 built when the host and target are the same system. Child process
4606 handling and core file support are two common `native' examples.
4608 GDB's use of /proc for controlling Unix child processes is now cleaner.
4609 It has been split out into a single module under the `target_ops' vector,
4610 plus two native-dependent functions for each system that uses /proc.
4612 * New hosts supported
4614 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4615 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4616 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4618 * New targets supported
4620 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4621 68030 and CPU32 m68030-*-*, m68332-*-*
4623 * New native hosts supported
4625 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4626 (386bsd is not well tested yet)
4627 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4629 * New file formats supported
4631 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4632 supports reading of `a.out.adobe' object files, which are an a.out
4633 format extended with minimal information about multiple sections.
4637 `show copying' is the same as the old `info copying'.
4638 `show warranty' is the same as `info warrantee'.
4639 These were renamed for consistency. The old commands continue to work.
4641 `info handle' is a new alias for `info signals'.
4643 You can now define pre-command hooks, which attach arbitrary command
4644 scripts to any command. The commands in the hook will be executed
4645 prior to the user's command. You can also create a hook which will be
4646 executed whenever the program stops. See gdb.texinfo.
4650 We now deal with Cfront style name mangling, and can even extract type
4651 info from mangled symbols. GDB can automatically figure out which
4652 symbol mangling style your C++ compiler uses.
4654 Calling of methods and virtual functions has been improved as well.
4658 The crash that occured when debugging Sun Ansi-C compiled binaries is
4659 fixed. This was due to mishandling of the extra N_SO stabs output
4662 We also finally got Ultrix 4.2 running in house, and fixed core file
4663 support, with help from a dozen people on the net.
4665 John M. Farrell discovered that the reason that single-stepping was so
4666 slow on all of the Mips based platforms (primarily SGI and DEC) was
4667 that we were trying to demangle and lookup a symbol used for internal
4668 purposes on every instruction that was being stepped through. Changing
4669 the name of that symbol so that it couldn't be mistaken for a C++
4670 mangled symbol sped things up a great deal.
4672 Rich Pixley sped up symbol lookups in general by getting much smarter
4673 about when C++ symbol mangling is necessary. This should make symbol
4674 completion (TAB on the command line) much faster. It's not as fast as
4675 we'd like, but it's significantly faster than gdb-4.6.
4679 A new user controllable variable 'call_scratch_address' can
4680 specify the location of a scratch area to be used when GDB
4681 calls a function in the target. This is necessary because the
4682 usual method of putting the scratch area on the stack does not work
4683 in systems that have separate instruction and data spaces.
4685 We integrated changes to support the 29k UDI (Universal Debugger
4686 Interface), but discovered at the last minute that we didn't have all
4687 of the appropriate copyright paperwork. We are working with AMD to
4688 resolve this, and hope to have it available soon.
4692 We have sped up the remote serial line protocol, especially for targets
4693 with lots of registers. It now supports a new `expedited status' ('T')
4694 message which can be used in place of the existing 'S' status message.
4695 This allows the remote stub to send only the registers that GDB
4696 needs to make a quick decision about single-stepping or conditional
4697 breakpoints, eliminating the need to fetch the entire register set for
4698 each instruction being stepped through.
4700 The GDB remote serial protocol now implements a write-through cache for
4701 registers, only re-reading the registers if the target has run.
4703 There is also a new remote serial stub for SPARC processors. You can
4704 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4705 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4706 processor with a serial port.
4710 Configure.in files have become much easier to read and modify. A new
4711 `table driven' format makes it more obvious what configurations are
4712 supported, and what files each one uses.
4716 There is a new opcodes library which will eventually contain all of the
4717 disassembly routines and opcode tables. At present, it only contains
4718 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4719 disassembler (binutils/objdump) to share these routines.
4721 The libiberty library is now copylefted under the GNU Library General
4722 Public License. This allows more liberal use, and was done so libg++
4723 can use it. This makes no difference to GDB, since the Library License
4724 grants all the rights from the General Public License.
4728 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4729 reference to the stabs symbol info used by the debugger. It is (as far
4730 as we know) the only published document on this fascinating topic. We
4731 encourage you to read it, compare it to the stabs information on your
4732 system, and send improvements on the document in general (to
4733 bug-gdb@prep.ai.mit.edu).
4735 And, of course, many bugs have been fixed.
4738 *** Changes in GDB-4.6:
4740 * Better support for C++ function names
4742 GDB now accepts as input the "demangled form" of C++ overloaded function
4743 names and member function names, and can do command completion on such names
4744 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4745 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4746 Make use of command completion, it is your friend.
4748 GDB also now accepts a variety of C++ mangled symbol formats. They are
4749 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4750 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4751 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4752 for the list of formats.
4754 * G++ symbol mangling problem
4756 Recent versions of gcc have a bug in how they emit debugging information for
4757 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4758 directory) can be applied to gcc to fix the problem. Alternatively, if you
4759 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4760 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4761 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4764 * New 'maintenance' command
4766 All of the commands related to hacking GDB internals have been moved out of
4767 the main command set, and now live behind the 'maintenance' command. This
4768 can also be abbreviated as 'mt'. The following changes were made:
4770 dump-me -> maintenance dump-me
4771 info all-breakpoints -> maintenance info breakpoints
4772 printmsyms -> maintenance print msyms
4773 printobjfiles -> maintenance print objfiles
4774 printpsyms -> maintenance print psymbols
4775 printsyms -> maintenance print symbols
4777 The following commands are new:
4779 maintenance demangle Call internal GDB demangler routine to
4780 demangle a C++ link name and prints the result.
4781 maintenance print type Print a type chain for a given symbol
4783 * Change to .gdbinit file processing
4785 We now read the $HOME/.gdbinit file before processing the argv arguments
4786 (e.g. reading symbol files or core files). This allows global parameters to
4787 be set, which will apply during the symbol reading. The ./.gdbinit is still
4788 read after argv processing.
4790 * New hosts supported
4792 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4794 GNU/Linux support i386-unknown-linux or linux
4796 We are also including code to support the HP/PA running BSD and HPUX. This
4797 is almost guaranteed not to work, as we didn't have time to test or build it
4798 for this release. We are including it so that the more adventurous (or
4799 masochistic) of you can play with it. We also had major problems with the
4800 fact that the compiler that we got from HP doesn't support the -g option.
4803 * New targets supported
4805 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4807 * More smarts about finding #include files
4809 GDB now remembers the compilation directory for all include files, and for
4810 all files from which C is generated (like yacc and lex sources). This
4811 greatly improves GDB's ability to find yacc/lex sources, and include files,
4812 especially if you are debugging your program from a directory different from
4813 the one that contains your sources.
4815 We also fixed a bug which caused difficulty with listing and setting
4816 breakpoints in include files which contain C code. (In the past, you had to
4817 try twice in order to list an include file that you hadn't looked at before.)
4819 * Interesting infernals change
4821 GDB now deals with arbitrary numbers of sections, where the symbols for each
4822 section must be relocated relative to that section's landing place in the
4823 target's address space. This work was needed to support ELF with embedded
4824 stabs used by Solaris-2.0.
4826 * Bug fixes (of course!)
4828 There have been loads of fixes for the following things:
4829 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4830 i960, stabs, DOS(GO32), procfs, etc...
4832 See the ChangeLog for details.
4834 *** Changes in GDB-4.5:
4836 * New machines supported (host and target)
4838 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4840 SGI Irix-4.x mips-sgi-irix4 or iris4
4842 * New malloc package
4844 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4845 Mmalloc is capable of handling mutiple heaps of memory. It is also
4846 capable of saving a heap to a file, and then mapping it back in later.
4847 This can be used to greatly speedup the startup of GDB by using a
4848 pre-parsed symbol table which lives in a mmalloc managed heap. For
4849 more details, please read mmalloc/mmalloc.texi.
4853 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4854 'help info proc' for details.
4856 * MIPS ecoff symbol table format
4858 The code that reads MIPS symbol table format is now supported on all hosts.
4859 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4862 * File name changes for MS-DOS
4864 Many files in the config directories have been renamed to make it easier to
4865 support GDB on MS-DOSe systems (which have very restrictive file name
4866 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4867 environment) is close to working but has some remaining problems. Note
4868 that debugging of DOS programs is not supported, due to limitations
4869 in the ``operating system'', but it can be used to host cross-debugging.
4871 * Cross byte order fixes
4873 Many fixes have been made to support cross debugging of Sparc and MIPS
4874 targets from hosts whose byte order differs.
4876 * New -mapped and -readnow options
4878 If memory-mapped files are available on your system through the 'mmap'
4879 system call, you can use the -mapped option on the `file' or
4880 `symbol-file' commands to cause GDB to write the symbols from your
4881 program into a reusable file. If the program you are debugging is
4882 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4883 Future GDB debugging sessions will notice the presence of this file,
4884 and will quickly map in symbol information from it, rather than reading
4885 the symbol table from the executable program. Using the '-mapped'
4886 option in a GDB `file' or `symbol-file' command has the same effect as
4887 starting GDB with the '-mapped' command-line option.
4889 You can cause GDB to read the entire symbol table immediately by using
4890 the '-readnow' option with any of the commands that load symbol table
4891 information (or on the GDB command line). This makes the command
4892 slower, but makes future operations faster.
4894 The -mapped and -readnow options are typically combined in order to
4895 build a `fred.syms' file that contains complete symbol information.
4896 A simple GDB invocation to do nothing but build a `.syms' file for future
4899 gdb -batch -nx -mapped -readnow programname
4901 The `.syms' file is specific to the host machine on which GDB is run.
4902 It holds an exact image of GDB's internal symbol table. It cannot be
4903 shared across multiple host platforms.
4905 * longjmp() handling
4907 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4908 siglongjmp() without losing control. This feature has not yet been ported to
4909 all systems. It currently works on many 386 platforms, all MIPS-based
4910 platforms (SGI, DECstation, etc), and Sun3/4.
4914 Preliminary work has been put in to support the new Solaris OS from Sun. At
4915 this time, it can control and debug processes, but it is not capable of
4920 As always, many many bug fixes. The major areas were with g++, and mipsread.
4921 People using the MIPS-based platforms should experience fewer mysterious
4922 crashes and trashed symbol tables.
4924 *** Changes in GDB-4.4:
4926 * New machines supported (host and target)
4928 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4930 BSD Reno on Vax vax-dec-bsd
4931 Ultrix on Vax vax-dec-ultrix
4933 * New machines supported (target)
4935 AMD 29000 embedded, using EBMON a29k-none-none
4939 GDB continues to improve its handling of C++. `References' work better.
4940 The demangler has also been improved, and now deals with symbols mangled as
4941 per the Annotated C++ Reference Guide.
4943 GDB also now handles `stabs' symbol information embedded in MIPS
4944 `ecoff' symbol tables. Since the ecoff format was not easily
4945 extensible to handle new languages such as C++, this appeared to be a
4946 good way to put C++ debugging info into MIPS binaries. This option
4947 will be supported in the GNU C compiler, version 2, when it is
4950 * New features for SVR4
4952 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4953 shared libraries. Debugging dynamically linked programs should present
4954 only minor differences from debugging statically linked programs.
4956 The `info proc' command will print out information about any process
4957 on an SVR4 system (including the one you are debugging). At the moment,
4958 it prints the address mappings of the process.
4960 If you bring up GDB on another SVR4 system, please send mail to
4961 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4963 * Better dynamic linking support in SunOS
4965 Reading symbols from shared libraries which contain debugging symbols
4966 now works properly. However, there remain issues such as automatic
4967 skipping of `transfer vector' code during function calls, which
4968 make it harder to debug code in a shared library, than to debug the
4969 same code linked statically.
4973 GDB is now using the latest `getopt' routines from the FSF. This
4974 version accepts the -- prefix for options with long names. GDB will
4975 continue to accept the old forms (-option and +option) as well.
4976 Various single letter abbreviations for options have been explicity
4977 added to the option table so that they won't get overshadowed in the
4978 future by other options that begin with the same letter.
4982 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4983 Many assorted bugs have been handled. Many more remain to be handled.
4984 See the various ChangeLog files (primarily in gdb and bfd) for details.
4987 *** Changes in GDB-4.3:
4989 * New machines supported (host and target)
4991 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4992 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4993 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4995 * Almost SCO Unix support
4997 We had hoped to support:
4998 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4999 (except for core file support), but we discovered very late in the release
5000 that it has problems with process groups that render gdb unusable. Sorry
5001 about that. I encourage people to fix it and post the fixes.
5003 * Preliminary ELF and DWARF support
5005 GDB can read ELF object files on System V Release 4, and can handle
5006 debugging records for C, in DWARF format, in ELF files. This support
5007 is preliminary. If you bring up GDB on another SVR4 system, please
5008 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5013 GDB now uses the latest `readline' library. One user-visible change
5014 is that two tabs will list possible command completions, which previously
5015 required typing M-? (meta-question mark, or ESC ?).
5019 The `stepi' bug that many of you noticed has been squashed.
5020 Many bugs in C++ have been handled. Many more remain to be handled.
5021 See the various ChangeLog files (primarily in gdb and bfd) for details.
5023 * State of the MIPS world (in case you wondered):
5025 GDB can understand the symbol tables emitted by the compilers
5026 supplied by most vendors of MIPS-based machines, including DEC. These
5027 symbol tables are in a format that essentially nobody else uses.
5029 Some versions of gcc come with an assembler post-processor called
5030 mips-tfile. This program is required if you want to do source-level
5031 debugging of gcc-compiled programs. I believe FSF does not ship
5032 mips-tfile with gcc version 1, but it will eventually come with gcc
5035 Debugging of g++ output remains a problem. g++ version 1.xx does not
5036 really support it at all. (If you're lucky, you should be able to get
5037 line numbers and stack traces to work, but no parameters or local
5038 variables.) With some work it should be possible to improve the
5041 When gcc version 2 is released, you will have somewhat better luck.
5042 However, even then you will get confusing results for inheritance and
5045 We will eventually provide full debugging of g++ output on
5046 DECstations. This will probably involve some kind of stabs-in-ecoff
5047 encapulation, but the details have not been worked out yet.
5050 *** Changes in GDB-4.2:
5052 * Improved configuration
5054 Only one copy of `configure' exists now, and it is not self-modifying.
5055 Porting BFD is simpler.
5059 The `step' and `next' commands now only stop at the first instruction
5060 of a source line. This prevents the multiple stops that used to occur
5061 in switch statements, for-loops, etc. `Step' continues to stop if a
5062 function that has debugging information is called within the line.
5066 Lots of small bugs fixed. More remain.
5068 * New host supported (not target)
5070 Intel 386 PC clone running Mach i386-none-mach
5073 *** Changes in GDB-4.1:
5075 * Multiple source language support
5077 GDB now has internal scaffolding to handle several source languages.
5078 It determines the type of each source file from its filename extension,
5079 and will switch expression parsing and number formatting to match the
5080 language of the function in the currently selected stack frame.
5081 You can also specifically set the language to be used, with
5082 `set language c' or `set language modula-2'.
5086 GDB now has preliminary support for the GNU Modula-2 compiler,
5087 currently under development at the State University of New York at
5088 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5089 continue through the fall of 1991 and into 1992.
5091 Other Modula-2 compilers are currently not supported, and attempting to
5092 debug programs compiled with them will likely result in an error as the
5093 symbol table is read. Feel free to work on it, though!
5095 There are hooks in GDB for strict type checking and range checking,
5096 in the `Modula-2 philosophy', but they do not currently work.
5100 GDB can now write to executable and core files (e.g. patch
5101 a variable's value). You must turn this switch on, specify
5102 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5103 by assigning a new value to a variable. Modifications take
5106 * Automatic SunOS shared library reading
5108 When you run your program, GDB automatically determines where its
5109 shared libraries (if any) have been loaded, and reads their symbols.
5110 The `share' command is no longer needed. This also works when
5111 examining core files.
5115 You can specify the number of lines that the `list' command shows.
5118 * New machines supported (host and target)
5120 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5121 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5122 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5124 * New hosts supported (not targets)
5126 IBM RT/PC: romp-ibm-aix or rtpc
5128 * New targets supported (not hosts)
5130 AMD 29000 embedded with COFF a29k-none-coff
5131 AMD 29000 embedded with a.out a29k-none-aout
5132 Ultracomputer remote kernel debug a29k-nyu-kern
5134 * New remote interfaces
5140 *** Changes in GDB-4.0:
5144 Wide output is wrapped at good places to make the output more readable.
5146 Gdb now supports cross-debugging from a host machine of one type to a
5147 target machine of another type. Communication with the target system
5148 is over serial lines. The ``target'' command handles connecting to the
5149 remote system; the ``load'' command will download a program into the
5150 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5151 also supports debugging of realtime processes running under VxWorks,
5152 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5153 stub on the target system.
5155 New CPUs supported include the AMD 29000 and Intel 960.
5157 GDB now reads object files and symbol tables via a ``binary file''
5158 library, which allows a single copy of GDB to debug programs of multiple
5159 object file types such as a.out and coff.
5161 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5162 refcard.dvi and refcard.ps are available to format it).
5165 * Control-Variable user interface simplified
5167 All variables that control the operation of the debugger can be set
5168 by the ``set'' command, and displayed by the ``show'' command.
5170 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5171 ``Show prompt'' produces the response:
5172 Gdb's prompt is new-gdb=>.
5174 What follows are the NEW set commands. The command ``help set'' will
5175 print a complete list of old and new set commands. ``help set FOO''
5176 will give a longer description of the variable FOO. ``show'' will show
5177 all of the variable descriptions and their current settings.
5179 confirm on/off: Enables warning questions for operations that are
5180 hard to recover from, e.g. rerunning the program while
5181 it is already running. Default is ON.
5183 editing on/off: Enables EMACS style command line editing
5184 of input. Previous lines can be recalled with
5185 control-P, the current line can be edited with control-B,
5186 you can search for commands with control-R, etc.
5189 history filename NAME: NAME is where the gdb command history
5190 will be stored. The default is .gdb_history,
5191 or the value of the environment variable
5194 history size N: The size, in commands, of the command history. The
5195 default is 256, or the value of the environment variable
5198 history save on/off: If this value is set to ON, the history file will
5199 be saved after exiting gdb. If set to OFF, the
5200 file will not be saved. The default is OFF.
5202 history expansion on/off: If this value is set to ON, then csh-like
5203 history expansion will be performed on
5204 command line input. The default is OFF.
5206 radix N: Sets the default radix for input and output. It can be set
5207 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5208 in the current radix, so "set radix 10" is always a no-op.
5210 height N: This integer value is the number of lines on a page. Default
5211 is 24, the current `stty rows'' setting, or the ``li#''
5212 setting from the termcap entry matching the environment
5215 width N: This integer value is the number of characters on a line.
5216 Default is 80, the current `stty cols'' setting, or the ``co#''
5217 setting from the termcap entry matching the environment
5220 Note: ``set screensize'' is obsolete. Use ``set height'' and
5221 ``set width'' instead.
5223 print address on/off: Print memory addresses in various command displays,
5224 such as stack traces and structure values. Gdb looks
5225 more ``symbolic'' if you turn this off; it looks more
5226 ``machine level'' with it on. Default is ON.
5228 print array on/off: Prettyprint arrays. New convenient format! Default
5231 print demangle on/off: Print C++ symbols in "source" form if on,
5234 print asm-demangle on/off: Same, for assembler level printouts
5237 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5240 * Support for Epoch Environment.
5242 The epoch environment is a version of Emacs v18 with windowing. One
5243 new command, ``inspect'', is identical to ``print'', except that if you
5244 are running in the epoch environment, the value is printed in its own
5248 * Support for Shared Libraries
5250 GDB can now debug programs and core files that use SunOS shared libraries.
5251 Symbols from a shared library cannot be referenced
5252 before the shared library has been linked with the program (this
5253 happens after you type ``run'' and before the function main() is entered).
5254 At any time after this linking (including when examining core files
5255 from dynamically linked programs), gdb reads the symbols from each
5256 shared library when you type the ``sharedlibrary'' command.
5257 It can be abbreviated ``share''.
5259 sharedlibrary REGEXP: Load shared object library symbols for files
5260 matching a unix regular expression. No argument
5261 indicates to load symbols for all shared libraries.
5263 info sharedlibrary: Status of loaded shared libraries.
5268 A watchpoint stops execution of a program whenever the value of an
5269 expression changes. Checking for this slows down execution
5270 tremendously whenever you are in the scope of the expression, but is
5271 quite useful for catching tough ``bit-spreader'' or pointer misuse
5272 problems. Some machines such as the 386 have hardware for doing this
5273 more quickly, and future versions of gdb will use this hardware.
5275 watch EXP: Set a watchpoint (breakpoint) for an expression.
5277 info watchpoints: Information about your watchpoints.
5279 delete N: Deletes watchpoint number N (same as breakpoints).
5280 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5281 enable N: Re-enables watchpoint number N (same as breakpoints).
5284 * C++ multiple inheritance
5286 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5289 * C++ exception handling
5291 Gdb now supports limited C++ exception handling. Besides the existing
5292 ability to breakpoint on an exception handler, gdb can breakpoint on
5293 the raising of an exception (before the stack is peeled back to the
5296 catch FOO: If there is a FOO exception handler in the dynamic scope,
5297 set a breakpoint to catch exceptions which may be raised there.
5298 Multiple exceptions (``catch foo bar baz'') may be caught.
5300 info catch: Lists all exceptions which may be caught in the
5301 current stack frame.
5304 * Minor command changes
5306 The command ``call func (arg, arg, ...)'' now acts like the print
5307 command, except it does not print or save a value if the function's result
5308 is void. This is similar to dbx usage.
5310 The ``up'' and ``down'' commands now always print the frame they end up
5311 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5312 frames without printing.
5314 * New directory command
5316 'dir' now adds directories to the FRONT of the source search path.
5317 The path starts off empty. Source files that contain debug information
5318 about the directory in which they were compiled can be found even
5319 with an empty path; Sun CC and GCC include this information. If GDB can't
5320 find your source file in the current directory, type "dir .".
5322 * Configuring GDB for compilation
5324 For normal use, type ``./configure host''. See README or gdb.texinfo
5327 GDB now handles cross debugging. If you are remotely debugging between
5328 two different machines, type ``./configure host -target=targ''.
5329 Host is the machine where GDB will run; targ is the machine
5330 where the program that you are debugging will run.