1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.6
8 Display the details of GDB configure-time options.
10 maint set|show per-command
11 maint set|show per-command space
12 maint set|show per-command time
13 maint set|show per-command symtab
14 Enable display of per-command gdb resource usage.
18 set remote trace-status-packet
19 show remote trace-status-packet
20 Set/show the use of remote protocol qTStatus packet.
22 * New command-line options
24 Display the details of GDB configure-time options.
26 * The command 'tsave' can now support new option '-ctf' to save trace
27 buffer in Common Trace Format.
29 * Newly installed $prefix/bin/gcore acts as a shell interface for the
32 * GDB now implements the the C++ 'typeid' operator.
36 ** The -trace-save MI command can optionally save trace buffer in Common
39 *** Changes in GDB 7.6
41 * Target record has been renamed to record-full.
42 Record/replay is now enabled with the "record full" command.
43 This also affects settings that are associated with full record/replay
44 that have been moved from "set/show record" to "set/show record full":
46 set|show record full insn-number-max
47 set|show record full stop-at-limit
48 set|show record full memory-query
50 * A new record target "record-btrace" has been added. The new target
51 uses hardware support to record the control-flow of a process. It
52 does not support replaying the execution, but it implements the
53 below new commands for investigating the recorded execution log.
54 This new recording method can be enabled using:
58 The "record-btrace" target is only available on Intel Atom processors
59 and requires a Linux kernel 2.6.32 or later.
61 * Two new commands have been added for record/replay to give information
62 about the recorded execution without having to replay the execution.
63 The commands are only supported by "record btrace".
65 record instruction-history prints the execution history at
66 instruction granularity
68 record function-call-history prints the execution history at
71 * New native configurations
73 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
74 FreeBSD/powerpc powerpc*-*-freebsd
75 x86_64/Cygwin x86_64-*-cygwin*
76 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
80 ARM AArch64 aarch64*-*-elf
81 ARM AArch64 GNU/Linux aarch64*-*-linux
82 Lynx 178 PowerPC powerpc-*-lynx*178
83 x86_64/Cygwin x86_64-*-cygwin*
84 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
86 * If the configured location of system.gdbinit file (as given by the
87 --with-system-gdbinit option at configure time) is in the
88 data-directory (as specified by --with-gdb-datadir at configure
89 time) or in one of its subdirectories, then GDB will look for the
90 system-wide init file in the directory specified by the
91 --data-directory command-line option.
93 * New command line options:
95 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
96 other initialization files, unlike -nx which disables all of them.
98 * Removed command line options
100 -epoch This was used by the gdb mode in Epoch, an ancient fork of
103 * The 'ptype' and 'whatis' commands now accept an argument to control
106 * 'info proc' now works on some core files.
108 * The new convenience variable $_exception holds the exception being
109 thrown or caught at an exception-related catchpoint.
113 ** Vectors can be created with gdb.Type.vector.
115 ** Python's atexit.register now works in GDB.
117 ** Types can be pretty-printed via a Python API.
119 ** Python 3 is now supported (in addition to Python 2.4 or later)
121 ** New class gdb.Architecture exposes GDB's internal representation
122 of architecture in the Python API.
124 ** New method Frame.architecture returns the gdb.Architecture object
125 corresponding to the frame's architecture.
127 * New Python-based convenience functions:
129 ** $_memeq(buf1, buf2, length)
130 ** $_streq(str1, str2)
132 ** $_regex(str, regex)
134 * The 'cd' command now defaults to using '~' (the home directory) if not
137 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
138 default for GCC since November 2000.
140 * The command 'forward-search' can now be abbreviated as 'fo'.
142 * The command 'info tracepoints' can now display 'installed on target'
143 or 'not installed on target' for each non-pending location of tracepoint.
145 * New configure options
147 --enable-libmcheck/--disable-libmcheck
148 By default, development versions are built with -lmcheck on hosts
149 that support it, in order to help track memory corruption issues.
150 Release versions, on the other hand, are built without -lmcheck
151 by default. The --enable-libmcheck/--disable-libmcheck configure
152 options allow the user to override that default.
153 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
154 This configure option allows the user to build GDB with
155 libbabeltrace using which GDB can read Common Trace Format data.
157 * New commands (for set/show, see "New options" below)
160 Like "catch throw", but catches a re-thrown exception.
163 Catch signals. This is similar to "handle", but allows commands and
164 conditions to be attached.
167 List the BFDs known to GDB.
169 python-interactive [command]
171 Start a Python interactive prompt, or evaluate the optional command
172 and print the result of expressions.
175 "py" is a new alias for "python".
177 enable type-printer [name]...
178 disable type-printer [name]...
179 Enable or disable type printers.
183 ** For the Renesas Super-H architecture, the "regs" command has been removed
184 (has been deprecated in GDB 7.5), and "info all-registers" should be used
189 set print type methods (on|off)
190 show print type methods
191 Control whether method declarations are displayed by "ptype".
192 The default is to show them.
194 set print type typedefs (on|off)
195 show print type typedefs
196 Control whether typedef definitions are displayed by "ptype".
197 The default is to show them.
199 set filename-display basename|relative|absolute
200 show filename-display
201 Control the way in which filenames is displayed.
202 The default is "relative", which preserves previous behavior.
204 set trace-buffer-size
205 show trace-buffer-size
206 Request target to change the size of trace buffer.
208 set remote trace-buffer-size-packet auto|on|off
209 show remote trace-buffer-size-packet
210 Control the use of the remote protocol `QTBuffer:size' packet.
214 Control display of debugging messages related to ARM AArch64.
217 set debug coff-pe-read
218 show debug coff-pe-read
219 Control display of debugging messages related to reading of COFF/PE
224 Control display of debugging messages related to Mach-O symbols
227 set debug notification
228 show debug notification
229 Control display of debugging info for async remote notification.
233 ** Command parameter changes are now notified using new async record
234 "=cmd-param-changed".
235 ** Trace frame changes caused by command "tfind" are now notified using
236 new async record "=traceframe-changed".
237 ** The creation, deletion and modification of trace state variables
238 are now notified using new async records "=tsv-created",
239 "=tsv-deleted" and "=tsv-modified".
240 ** The start and stop of process record are now notified using new
241 async record "=record-started" and "=record-stopped".
242 ** Memory changes are now notified using new async record
244 ** The data-disassemble command response will include a "fullname" field
245 containing the absolute file name when source has been requested.
246 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
247 command, to allow pattern filling of memory areas.
248 ** New commands "-catch-load"/"-catch-unload" added for intercepting
249 library load/unload events.
250 ** The response to breakpoint commands and breakpoint async records
251 includes an "installed" field containing a boolean state about each
252 non-pending tracepoint location is whether installed on target or not.
253 ** Output of the "-trace-status" command includes a "trace-file" field
254 containing the name of the trace file being examined. This field is
255 optional, and only present when examining a trace file.
256 ** The "fullname" field is now always present along with the "file" field,
257 even if the file cannot be found by GDB.
259 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
260 You must have the LZMA library available when configuring GDB for this
261 feature to be enabled. For more information, see:
262 http://fedoraproject.org/wiki/Features/MiniDebugInfo
267 Set the size of trace buffer. The remote stub reports support for this
268 packet to gdb's qSupported query.
271 Enable Branch Trace Store (BTS)-based branch tracing for the current
272 thread. The remote stub reports support for this packet to gdb's
276 Disable branch tracing for the current thread. The remote stub reports
277 support for this packet to gdb's qSupported query.
280 Read the traced branches for the current thread. The remote stub
281 reports support for this packet to gdb's qSupported query.
283 *** Changes in GDB 7.5
285 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
286 for more x32 ABI info.
288 * GDB now supports access to MIPS DSP registers on Linux targets.
290 * GDB now supports debugging microMIPS binaries.
292 * The "info os" command on GNU/Linux can now display information on
293 several new classes of objects managed by the operating system:
294 "info os procgroups" lists process groups
295 "info os files" lists file descriptors
296 "info os sockets" lists internet-domain sockets
297 "info os shm" lists shared-memory regions
298 "info os semaphores" lists semaphores
299 "info os msg" lists message queues
300 "info os modules" lists loaded kernel modules
302 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
303 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
304 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
305 options and inspect the probe arguments using the new $_probe_arg family
306 of convenience variables. You can obtain more information about SystemTap
307 in <http://sourceware.org/systemtap/>.
309 * GDB now supports reversible debugging on ARM, it allows you to
310 debug basic ARM and THUMB instructions, and provides
311 record/replay support.
313 * The option "symbol-reloading" has been deleted as it is no longer used.
317 ** GDB commands implemented in Python can now be put in command class
320 ** The "maint set python print-stack on|off" is now deleted.
322 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
323 apply "flag enum"-style pretty-printing to any enum.
325 ** gdb.lookup_symbol can now work when there is no current frame.
327 ** gdb.Symbol now has a 'line' attribute, holding the line number in
328 the source at which the symbol was defined.
330 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
331 method 'value'. The former indicates whether the symbol needs a
332 frame in order to compute its value, and the latter computes the
335 ** A new method 'referenced_value' on gdb.Value objects which can
336 dereference pointer as well as C++ reference values.
338 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
339 which return the global and static blocks (as gdb.Block objects),
340 of the underlying symbol table, respectively.
342 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
343 object associated with a PC value.
345 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
346 of the address range occupied by code for the current source line.
348 * Go language support.
349 GDB now supports debugging programs written in the Go programming
352 * GDBserver now supports stdio connections.
353 E.g. (gdb) target remote | ssh myhost gdbserver - hello
355 * The binary "gdbtui" can no longer be built or installed.
356 Use "gdb -tui" instead.
358 * GDB will now print "flag" enums specially. A flag enum is one where
359 all the enumerator values have no bits in common when pairwise
360 "and"ed. When printing a value whose type is a flag enum, GDB will
361 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
362 (gdb) print (enum E) 3
365 * The filename part of a linespec will now match trailing components
366 of a source file name. For example, "break gcc/expr.c:1000" will
367 now set a breakpoint in build/gcc/expr.c, but not
370 * The "info proc" and "generate-core-file" commands will now also
371 work on remote targets connected to GDBserver on Linux.
373 * The command "info catch" has been removed. It has been disabled
376 * The "catch exception" and "catch assert" commands now accept
377 a condition at the end of the command, much like the "break"
378 command does. For instance:
380 (gdb) catch exception Constraint_Error if Barrier = True
382 Previously, it was possible to add a condition to such catchpoints,
383 but it had to be done as a second step, after the catchpoint had been
384 created, using the "condition" command.
386 * The "info static-tracepoint-marker" command will now also work on
387 native Linux targets with in-process agent.
389 * GDB can now set breakpoints on inlined functions.
391 * The .gdb_index section has been updated to include symbols for
392 inlined functions. GDB will ignore older .gdb_index sections by
393 default, which could cause symbol files to be loaded more slowly
394 until their .gdb_index sections can be recreated. The new command
395 "set use-deprecated-index-sections on" will cause GDB to use any older
396 .gdb_index sections it finds. This will restore performance, but the
397 ability to set breakpoints on inlined functions will be lost in symbol
398 files with older .gdb_index sections.
400 The .gdb_index section has also been updated to record more information
401 about each symbol. This speeds up the "info variables", "info functions"
402 and "info types" commands when used with programs having the .gdb_index
403 section, as well as speeding up debugging with shared libraries using
404 the .gdb_index section.
406 * Ada support for GDB/MI Variable Objects has been added.
408 * GDB can now support 'breakpoint always-inserted mode' in 'record'
413 ** New command -info-os is the MI equivalent of "info os".
415 ** Output logs ("set logging" and related) now include MI output.
419 ** "set use-deprecated-index-sections on|off"
420 "show use-deprecated-index-sections on|off"
421 Controls the use of deprecated .gdb_index sections.
423 ** "catch load" and "catch unload" can be used to stop when a shared
424 library is loaded or unloaded, respectively.
426 ** "enable count" can be used to auto-disable a breakpoint after
429 ** "info vtbl" can be used to show the virtual method tables for
430 C++ and Java objects.
432 ** "explore" and its sub commands "explore value" and "explore type"
433 can be used to reccursively explore values and types of
434 expressions. These commands are available only if GDB is
435 configured with '--with-python'.
437 ** "info auto-load" shows status of all kinds of auto-loaded files,
438 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
439 sequences of commands files, "info auto-load python-scripts"
440 shows status of auto-loading Python script files,
441 "info auto-load local-gdbinit" shows status of loading init file
442 (.gdbinit) from current directory and "info auto-load libthread-db" shows
443 status of inferior specific thread debugging shared library loading.
445 ** "info auto-load-scripts", "set auto-load-scripts on|off"
446 and "show auto-load-scripts" commands have been deprecated, use their
447 "info auto-load python-scripts", "set auto-load python-scripts on|off"
448 and "show auto-load python-scripts" counterparts instead.
450 ** "dprintf location,format,args..." creates a dynamic printf, which
451 is basically a breakpoint that does a printf and immediately
452 resumes your program's execution, so it is like a printf that you
453 can insert dynamically at runtime instead of at compiletime.
455 ** "set print symbol"
457 Controls whether GDB attempts to display the symbol, if any,
458 corresponding to addresses it prints. This defaults to "on", but
459 you can set it to "off" to restore GDB's previous behavior.
461 * Deprecated commands
463 ** For the Renesas Super-H architecture, the "regs" command has been
464 deprecated, and "info all-registers" should be used instead.
468 Renesas RL78 rl78-*-elf
469 HP OpenVMS ia64 ia64-hp-openvms*
471 * GDBserver supports evaluation of breakpoint conditions. When
472 support is advertised by GDBserver, GDB may be told to send the
473 breakpoint conditions in bytecode form to GDBserver. GDBserver
474 will only report the breakpoint trigger to GDB when its condition
480 show mips compression
481 Select the compressed ISA encoding used in functions that have no symbol
482 information available. The encoding can be set to either of:
485 and is updated automatically from ELF file flags if available.
487 set breakpoint condition-evaluation
488 show breakpoint condition-evaluation
489 Control whether breakpoint conditions are evaluated by GDB ("host") or by
490 GDBserver ("target"). Default option "auto" chooses the most efficient
492 This option can improve debugger efficiency depending on the speed of the
496 Disable auto-loading globally.
499 Show auto-loading setting of all kinds of auto-loaded files.
501 set auto-load gdb-scripts on|off
502 show auto-load gdb-scripts
503 Control auto-loading of GDB canned sequences of commands files.
505 set auto-load python-scripts on|off
506 show auto-load python-scripts
507 Control auto-loading of Python script files.
509 set auto-load local-gdbinit on|off
510 show auto-load local-gdbinit
511 Control loading of init file (.gdbinit) from current directory.
513 set auto-load libthread-db on|off
514 show auto-load libthread-db
515 Control auto-loading of inferior specific thread debugging shared library.
517 set auto-load scripts-directory <dir1>[:<dir2>...]
518 show auto-load scripts-directory
519 Set a list of directories from which to load auto-loaded scripts.
520 Automatically loaded Python scripts and GDB scripts are located in one
521 of the directories listed by this option.
522 The delimiter (':' above) may differ according to the host platform.
524 set auto-load safe-path <dir1>[:<dir2>...]
525 show auto-load safe-path
526 Set a list of directories from which it is safe to auto-load files.
527 The delimiter (':' above) may differ according to the host platform.
529 set debug auto-load on|off
531 Control display of debugging info for auto-loading the files above.
533 set dprintf-style gdb|call|agent
535 Control the way in which a dynamic printf is performed; "gdb"
536 requests a GDB printf command, while "call" causes dprintf to call a
537 function in the inferior. "agent" requests that the target agent
538 (such as GDBserver) do the printing.
540 set dprintf-function <expr>
541 show dprintf-function
542 set dprintf-channel <expr>
544 Set the function and optional first argument to the call when using
545 the "call" style of dynamic printf.
547 set disconnected-dprintf on|off
548 show disconnected-dprintf
549 Control whether agent-style dynamic printfs continue to be in effect
550 after GDB disconnects.
552 * New configure options
555 Configure default value for the 'set auto-load scripts-directory'
556 setting above. It defaults to '$debugdir:$datadir/auto-load',
557 $debugdir representing global debugging info directories (available
558 via 'show debug-file-directory') and $datadir representing GDB's data
559 directory (available via 'show data-directory').
561 --with-auto-load-safe-path
562 Configure default value for the 'set auto-load safe-path' setting
563 above. It defaults to the --with-auto-load-dir setting.
565 --without-auto-load-safe-path
566 Set 'set auto-load safe-path' to '/', effectively disabling this
571 z0/z1 conditional breakpoints extension
573 The z0/z1 breakpoint insertion packets have been extended to carry
574 a list of conditional expressions over to the remote stub depending on the
575 condition evaluation mode. The use of this extension can be controlled
576 via the "set remote conditional-breakpoints-packet" command.
580 Specify the signals which the remote stub may pass to the debugged
581 program without GDB involvement.
583 * New command line options
585 --init-command=FILE, -ix Like --command, -x but execute it
586 before loading inferior.
587 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
588 execute it before loading inferior.
590 *** Changes in GDB 7.4
592 * GDB now handles ambiguous linespecs more consistently; the existing
593 FILE:LINE support has been expanded to other types of linespecs. A
594 breakpoint will now be set on all matching locations in all
595 inferiors, and locations will be added or removed according to
598 * GDB now allows you to skip uninteresting functions and files when
599 stepping with the "skip function" and "skip file" commands.
601 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
602 and "show remote hardware-watchpoint-length-limit". These allows to
603 set or show the maximum length limit (in bytes) of a remote
604 target hardware watchpoint.
606 This allows e.g. to use "unlimited" hardware watchpoints with the
607 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
608 watchpoints are slower than real hardware watchpoints but are
609 significantly faster than gdb software watchpoints.
613 ** The register_pretty_printer function in module gdb.printing now takes
614 an optional `replace' argument. If True, the new printer replaces any
617 ** The "maint set python print-stack on|off" command has been
618 deprecated and will be deleted in GDB 7.5.
619 A new command: "set python print-stack none|full|message" has
620 replaced it. Additionally, the default for "print-stack" is
621 now "message", which just prints the error message without
624 ** A prompt substitution hook (prompt_hook) is now available to the
627 ** A new Python module, gdb.prompt has been added to the GDB Python
628 modules library. This module provides functionality for
629 escape sequences in prompts (used by set/show
630 extended-prompt). These escape sequences are replaced by their
633 ** Python commands and convenience-functions located in
634 'data-directory'/python/gdb/command and
635 'data-directory'/python/gdb/function are now automatically loaded
638 ** Blocks now provide four new attributes. global_block and
639 static_block will return the global and static blocks
640 respectively. is_static and is_global are boolean attributes
641 that indicate if the block is one of those two types.
643 ** Symbols now provide the "type" attribute, the type of the symbol.
645 ** The "gdb.breakpoint" function has been deprecated in favor of
648 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
649 of a function. This class is based on the "finish" command
650 available in the CLI.
652 ** Type objects for struct and union types now allow access to
653 the fields using standard Python dictionary (mapping) methods.
654 For example, "some_type['myfield']" now works, as does
657 ** A new event "gdb.new_objfile" has been added, triggered by loading a
660 ** A new function, "deep_items" has been added to the gdb.types
661 module in the GDB Python modules library. This function returns
662 an iterator over the fields of a struct or union type. Unlike
663 the standard Python "iteritems" method, it will recursively traverse
664 any anonymous fields.
668 ** "*stopped" events can report several new "reason"s, such as
671 ** Breakpoint changes are now notified using new async records, like
672 "=breakpoint-modified".
674 ** New command -ada-task-info.
676 * libthread-db-search-path now supports two special values: $sdir and $pdir.
677 $sdir specifies the default system locations of shared libraries.
678 $pdir specifies the directory where the libpthread used by the application
681 GDB no longer looks in $sdir and $pdir after it has searched the directories
682 mentioned in libthread-db-search-path. If you want to search those
683 directories, they must be specified in libthread-db-search-path.
684 The default value of libthread-db-search-path on GNU/Linux and Solaris
685 systems is now "$sdir:$pdir".
687 $pdir is not supported by gdbserver, it is currently ignored.
688 $sdir is supported by gdbserver.
690 * New configure option --with-iconv-bin.
691 When using the internationalization support like the one in the GNU C
692 library, GDB will invoke the "iconv" program to get a list of supported
693 character sets. If this program lives in a non-standard location, one can
694 use this option to specify where to find it.
696 * When natively debugging programs on PowerPC BookE processors running
697 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
698 watchpoints, which specify a mask in addition to an address to watch.
699 The mask specifies that some bits of an address (the bits which are
700 reset in the mask) should be ignored when matching the address accessed
701 by the inferior against the watchpoint address. See the "PowerPC Embedded"
702 section in the user manual for more details.
704 * The new option --once causes GDBserver to stop listening for connections once
705 the first connection is made. The listening port used by GDBserver will
706 become available after that.
708 * New commands "info macros" and "alias" have been added.
710 * New function parameters suffix @entry specifies value of function parameter
711 at the time the function got called. Entry values are available only since
717 "!" is now an alias of the "shell" command.
718 Note that no space is needed between "!" and SHELL COMMAND.
722 watch EXPRESSION mask MASK_VALUE
723 The watch command now supports the mask argument which allows creation
724 of masked watchpoints, if the current architecture supports this feature.
726 info auto-load-scripts [REGEXP]
727 This command was formerly named "maintenance print section-scripts".
728 It is now generally useful and is no longer a maintenance-only command.
730 info macro [-all] [--] MACRO
731 The info macro command has new options `-all' and `--'. The first for
732 printing all definitions of a macro. The second for explicitly specifying
733 the end of arguments and the beginning of the macro name in case the macro
734 name starts with a hyphen.
736 collect[/s] EXPRESSIONS
737 The tracepoint collect command now takes an optional modifier "/s"
738 that directs it to dereference pointer-to-character types and
739 collect the bytes of memory up to a zero byte. The behavior is
740 similar to what you see when you use the regular print command on a
741 string. An optional integer following the "/s" sets a bound on the
742 number of bytes that will be collected.
745 The trace start command now interprets any supplied arguments as a
746 note to be recorded with the trace run, with an effect similar to
747 setting the variable trace-notes.
750 The trace stop command now interprets any arguments as a note to be
751 mentioned along with the tstatus report that the trace was stopped
752 with a command. The effect is similar to setting the variable
755 * Tracepoints can now be enabled and disabled at any time after a trace
756 experiment has been started using the standard "enable" and "disable"
757 commands. It is now possible to start a trace experiment with no enabled
758 tracepoints; GDB will display a warning, but will allow the experiment to
759 begin, assuming that tracepoints will be enabled as needed while the trace
762 * Fast tracepoints on 32-bit x86-architectures can now be placed at
763 locations with 4-byte instructions, when they were previously
764 limited to locations with instructions of 5 bytes or longer.
768 set debug dwarf2-read
769 show debug dwarf2-read
770 Turns on or off display of debugging messages related to reading
771 DWARF debug info. The default is off.
773 set debug symtab-create
774 show debug symtab-create
775 Turns on or off display of debugging messages related to symbol table
776 creation. The default is off.
780 Set the GDB prompt, and allow escape sequences to be inserted to
781 display miscellaneous information (see 'help set extended-prompt'
782 for the list of sequences). This prompt (and any information
783 accessed through the escape sequences) is updated every time the
786 set print entry-values (both|compact|default|if-needed|no|only|preferred)
787 show print entry-values
788 Set printing of frame argument values at function entry. In some cases
789 GDB can determine the value of function argument which was passed by the
790 function caller, even if the value was modified inside the called function.
792 set debug entry-values
793 show debug entry-values
794 Control display of debugging info for determining frame argument values at
795 function entry and virtual tail call frames.
797 set basenames-may-differ
798 show basenames-may-differ
799 Set whether a source file may have multiple base names.
800 (A "base name" is the name of a file with the directory part removed.
801 Example: The base name of "/home/user/hello.c" is "hello.c".)
802 If set, GDB will canonicalize file names (e.g., expand symlinks)
803 before comparing them. Canonicalization is an expensive operation,
804 but it allows the same file be known by more than one base name.
805 If not set (the default), all source files are assumed to have just
806 one base name, and gdb will do file name comparisons more efficiently.
812 Set a user name and notes for the current and any future trace runs.
813 This is useful for long-running and/or disconnected traces, to
814 inform others (or yourself) as to who is running the trace, supply
815 contact information, or otherwise explain what is going on.
818 show trace-stop-notes
819 Set a note attached to the trace run, that is displayed when the
820 trace has been stopped by a tstop command. This is useful for
821 instance as an explanation, if you are stopping a trace run that was
822 started by someone else.
828 Dynamically enable a tracepoint in a started trace experiment.
832 Dynamically disable a tracepoint in a started trace experiment.
836 Set the user and notes of the trace run.
840 Query the current status of a tracepoint.
844 Query the minimum length of instruction at which a fast tracepoint may
847 * Dcache size (number of lines) and line-size are now runtime-configurable
848 via "set dcache line" and "set dcache line-size" commands.
852 Texas Instruments TMS320C6x tic6x-*-*
856 Renesas RL78 rl78-*-elf
858 *** Changes in GDB 7.3.1
860 * The build failure for NetBSD and OpenBSD targets have now been fixed.
862 *** Changes in GDB 7.3
864 * GDB has a new command: "thread find [REGEXP]".
865 It finds the thread id whose name, target id, or thread extra info
866 matches the given regular expression.
868 * The "catch syscall" command now works on mips*-linux* targets.
870 * The -data-disassemble MI command now supports modes 2 and 3 for
871 dumping the instruction opcodes.
873 * New command line options
875 -data-directory DIR Specify DIR as the "data-directory".
876 This is mostly for testing purposes.
878 * The "maint set python auto-load on|off" command has been renamed to
879 "set auto-load-scripts on|off".
881 * GDB has a new command: "set directories".
882 It is like the "dir" command except that it replaces the
883 source path list instead of augmenting it.
885 * GDB now understands thread names.
887 On GNU/Linux, "info threads" will display the thread name as set by
888 prctl or pthread_setname_np.
890 There is also a new command, "thread name", which can be used to
891 assign a name internally for GDB to display.
894 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
895 has been integrated into GDB.
899 ** The function gdb.Write now accepts an optional keyword 'stream'.
900 This keyword, when provided, will direct the output to either
901 stdout, stderr, or GDB's logging output.
903 ** Parameters can now be be sub-classed in Python, and in particular
904 you may implement the get_set_doc and get_show_doc functions.
905 This improves how Parameter set/show documentation is processed
906 and allows for more dynamic content.
908 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
909 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
910 have an is_valid method.
912 ** Breakpoints can now be sub-classed in Python, and in particular
913 you may implement a 'stop' function that is executed each time
914 the inferior reaches that breakpoint.
916 ** New function gdb.lookup_global_symbol looks up a global symbol.
918 ** GDB values in Python are now callable if the value represents a
919 function. For example, if 'some_value' represents a function that
920 takes two integer parameters and returns a value, you can call
921 that function like so:
923 result = some_value (10,20)
925 ** Module gdb.types has been added.
926 It contains a collection of utilities for working with gdb.Types objects:
927 get_basic_type, has_field, make_enum_dict.
929 ** Module gdb.printing has been added.
930 It contains utilities for writing and registering pretty-printers.
931 New classes: PrettyPrinter, SubPrettyPrinter,
932 RegexpCollectionPrettyPrinter.
933 New function: register_pretty_printer.
935 ** New commands "info pretty-printers", "enable pretty-printer" and
936 "disable pretty-printer" have been added.
938 ** gdb.parameter("directories") is now available.
940 ** New function gdb.newest_frame returns the newest frame in the
943 ** The gdb.InferiorThread class has a new "name" attribute. This
944 holds the thread's name.
946 ** Python Support for Inferior events.
947 Python scripts can add observers to be notified of events
948 occurring in the process being debugged.
949 The following events are currently supported:
950 - gdb.events.cont Continue event.
951 - gdb.events.exited Inferior exited event.
952 - gdb.events.stop Signal received, and Breakpoint hit events.
956 ** GDB now puts template parameters in scope when debugging in an
957 instantiation. For example, if you have:
959 template<int X> int func (void) { return X; }
961 then if you step into func<5>, "print X" will show "5". This
962 feature requires proper debuginfo support from the compiler; it
963 was added to GCC 4.5.
965 ** The motion commands "next", "finish", "until", and "advance" now
966 work better when exceptions are thrown. In particular, GDB will
967 no longer lose control of the inferior; instead, the GDB will
968 stop the inferior at the point at which the exception is caught.
969 This functionality requires a change in the exception handling
970 code that was introduced in GCC 4.5.
972 * GDB now follows GCC's rules on accessing volatile objects when
973 reading or writing target state during expression evaluation.
974 One notable difference to prior behavior is that "print x = 0"
975 no longer generates a read of x; the value of the assignment is
976 now always taken directly from the value being assigned.
978 * GDB now has some support for using labels in the program's source in
979 linespecs. For instance, you can use "advance label" to continue
980 execution to a label.
982 * GDB now has support for reading and writing a new .gdb_index
983 section. This section holds a fast index of DWARF debugging
984 information and can be used to greatly speed up GDB startup and
985 operation. See the documentation for `save gdb-index' for details.
987 * The "watch" command now accepts an optional "-location" argument.
988 When used, this causes GDB to watch the memory referred to by the
989 expression. Such a watchpoint is never deleted due to it going out
992 * GDB now supports thread debugging of core dumps on GNU/Linux.
994 GDB now activates thread debugging using the libthread_db library
995 when debugging GNU/Linux core dumps, similarly to when debugging
996 live processes. As a result, when debugging a core dump file, GDB
997 is now able to display pthread_t ids of threads. For example, "info
998 threads" shows the same output as when debugging the process when it
999 was live. In earlier releases, you'd see something like this:
1002 * 1 LWP 6780 main () at main.c:10
1004 While now you see this:
1007 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1009 It is also now possible to inspect TLS variables when debugging core
1012 When debugging a core dump generated on a machine other than the one
1013 used to run GDB, you may need to point GDB at the correct
1014 libthread_db library with the "set libthread-db-search-path"
1015 command. See the user manual for more details on this command.
1017 * When natively debugging programs on PowerPC BookE processors running
1018 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1019 which stop execution of the inferior whenever it executes an instruction
1020 at any address within the specified range. See the "PowerPC Embedded"
1021 section in the user manual for more details.
1023 * New features in the GDB remote stub, GDBserver
1025 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1026 and i686 LynxOS (version 5.x).
1028 ** GDBserver is now supported on Blackfin Linux.
1030 * New native configurations
1032 ia64 HP-UX ia64-*-hpux*
1036 Analog Devices, Inc. Blackfin Processor bfin-*
1038 * Ada task switching is now supported on sparc-elf targets when
1039 debugging a program using the Ravenscar Profile. For more information,
1040 see the "Tasking Support when using the Ravenscar Profile" section
1041 in the GDB user manual.
1043 * Guile support was removed.
1045 * New features in the GNU simulator
1047 ** The --map-info flag lists all known core mappings.
1049 ** CFI flashes may be simulated via the "cfi" device.
1051 *** Changes in GDB 7.2
1053 * Shared library support for remote targets by default
1055 When GDB is configured for a generic, non-OS specific target, like
1056 for example, --target=arm-eabi or one of the many *-*-elf targets,
1057 GDB now queries remote stubs for loaded shared libraries using the
1058 `qXfer:libraries:read' packet. Previously, shared library support
1059 was always disabled for such configurations.
1063 ** Argument Dependent Lookup (ADL)
1065 In C++ ADL lookup directs function search to the namespaces of its
1066 arguments even if the namespace has not been imported.
1076 Here the compiler will search for `foo' in the namespace of 'b'
1077 and find A::foo. GDB now supports this. This construct is commonly
1078 used in the Standard Template Library for operators.
1080 ** Improved User Defined Operator Support
1082 In addition to member operators, GDB now supports lookup of operators
1083 defined in a namespace and imported with a `using' directive, operators
1084 defined in the global scope, operators imported implicitly from an
1085 anonymous namespace, and the ADL operators mentioned in the previous
1087 GDB now also supports proper overload resolution for all the previously
1088 mentioned flavors of operators.
1090 ** static const class members
1092 Printing of static const class members that are initialized in the
1093 class definition has been fixed.
1095 * Windows Thread Information Block access.
1097 On Windows targets, GDB now supports displaying the Windows Thread
1098 Information Block (TIB) structure. This structure is visible either
1099 by using the new command `info w32 thread-information-block' or, by
1100 dereferencing the new convenience variable named `$_tlb', a
1101 thread-specific pointer to the TIB. This feature is also supported
1102 when remote debugging using GDBserver.
1104 * Static tracepoints
1106 Static tracepoints are calls in the user program into a tracing
1107 library. One such library is a port of the LTTng kernel tracer to
1108 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1109 When debugging with GDBserver, GDB now supports combining the GDB
1110 tracepoint machinery with such libraries. For example: the user can
1111 use GDB to probe a static tracepoint marker (a call from the user
1112 program into the tracing library) with the new "strace" command (see
1113 "New commands" below). This creates a "static tracepoint" in the
1114 breakpoint list, that can be manipulated with the same feature set
1115 as fast and regular tracepoints. E.g., collect registers, local and
1116 global variables, collect trace state variables, and define
1117 tracepoint conditions. In addition, the user can collect extra
1118 static tracepoint marker specific data, by collecting the new
1119 $_sdata internal variable. When analyzing the trace buffer, you can
1120 inspect $_sdata like any other variable available to GDB. For more
1121 information, see the "Tracepoints" chapter in GDB user manual. New
1122 remote packets have been defined to support static tracepoints, see
1123 the "New remote packets" section below.
1125 * Better reconstruction of tracepoints after disconnected tracing
1127 GDB will attempt to download the original source form of tracepoint
1128 definitions when starting a trace run, and then will upload these
1129 upon reconnection to the target, resulting in a more accurate
1130 reconstruction of the tracepoints that are in use on the target.
1134 You can now exercise direct control over the ways that GDB can
1135 affect your program. For instance, you can disallow the setting of
1136 breakpoints, so that the program can run continuously (assuming
1137 non-stop mode). In addition, the "observer" variable is available
1138 to switch all of the different controls; in observer mode, GDB
1139 cannot affect the target's behavior at all, which is useful for
1140 tasks like diagnosing live systems in the field.
1142 * The new convenience variable $_thread holds the number of the
1145 * New remote packets
1149 Return the address of the Windows Thread Information Block of a given thread.
1153 In response to several of the tracepoint packets, the target may now
1154 also respond with a number of intermediate `qRelocInsn' request
1155 packets before the final result packet, to have GDB handle
1156 relocating an instruction to execute at a different address. This
1157 is particularly useful for stubs that support fast tracepoints. GDB
1158 reports support for this feature in the qSupported packet.
1162 List static tracepoint markers in the target program.
1166 List static tracepoint markers at a given address in the target
1169 qXfer:statictrace:read
1171 Read the static trace data collected (by a `collect $_sdata'
1172 tracepoint action). The remote stub reports support for this packet
1173 to gdb's qSupported query.
1177 Send the current settings of GDB's permission flags.
1181 Send part of the source (textual) form of a tracepoint definition,
1182 which includes location, conditional, and action list.
1184 * The source command now accepts a -s option to force searching for the
1185 script in the source search path even if the script name specifies
1188 * New features in the GDB remote stub, GDBserver
1190 - GDBserver now support tracepoints (including fast tracepoints, and
1191 static tracepoints). The feature is currently supported by the
1192 i386-linux and amd64-linux builds. See the "Tracepoints support
1193 in gdbserver" section in the manual for more information.
1195 GDBserver JIT compiles the tracepoint's conditional agent
1196 expression bytecode into native code whenever possible for low
1197 overhead dynamic tracepoints conditionals. For such tracepoints,
1198 an expression that examines program state is evaluated when the
1199 tracepoint is reached, in order to determine whether to capture
1200 trace data. If the condition is simple and false, processing the
1201 tracepoint finishes very quickly and no data is gathered.
1203 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1204 for static tracepoints support.
1206 - GDBserver now supports x86_64 Windows 64-bit debugging.
1208 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1209 it understands register description.
1211 * The --batch flag now disables pagination and queries.
1213 * X86 general purpose registers
1215 GDB now supports reading/writing byte, word and double-word x86
1216 general purpose registers directly. This means you can use, say,
1217 $ah or $ax to refer, respectively, to the byte register AH and
1218 16-bit word register AX that are actually portions of the 32-bit
1219 register EAX or 64-bit register RAX.
1221 * The `commands' command now accepts a range of breakpoints to modify.
1222 A plain `commands' following a command that creates multiple
1223 breakpoints affects all the breakpoints set by that command. This
1224 applies to breakpoints set by `rbreak', and also applies when a
1225 single `break' command creates multiple breakpoints (e.g.,
1226 breakpoints on overloaded c++ functions).
1228 * The `rbreak' command now accepts a filename specification as part of
1229 its argument, limiting the functions selected by the regex to those
1230 in the specified file.
1232 * Support for remote debugging Windows and SymbianOS shared libraries
1233 from Unix hosts has been improved. Non Windows GDB builds now can
1234 understand target reported file names that follow MS-DOS based file
1235 system semantics, such as file names that include drive letters and
1236 use the backslash character as directory separator. This makes it
1237 possible to transparently use the "set sysroot" and "set
1238 solib-search-path" on Unix hosts to point as host copies of the
1239 target's shared libraries. See the new command "set
1240 target-file-system-kind" described below, and the "Commands to
1241 specify files" section in the user manual for more information.
1245 eval template, expressions...
1246 Convert the values of one or more expressions under the control
1247 of the string template to a command line, and call it.
1249 set target-file-system-kind unix|dos-based|auto
1250 show target-file-system-kind
1251 Set or show the assumed file system kind for target reported file
1254 save breakpoints <filename>
1255 Save all current breakpoint definitions to a file suitable for use
1256 in a later debugging session. To read the saved breakpoint
1257 definitions, use the `source' command.
1259 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1262 info static-tracepoint-markers
1263 Display information about static tracepoint markers in the target.
1265 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1266 Define a static tracepoint by probing a marker at the given
1267 function, line, address, or marker ID.
1271 Enable and disable observer mode.
1273 set may-write-registers on|off
1274 set may-write-memory on|off
1275 set may-insert-breakpoints on|off
1276 set may-insert-tracepoints on|off
1277 set may-insert-fast-tracepoints on|off
1278 set may-interrupt on|off
1279 Set individual permissions for GDB effects on the target. Note that
1280 some of these settings can have undesirable or surprising
1281 consequences, particularly when changed in the middle of a session.
1282 For instance, disabling the writing of memory can prevent
1283 breakpoints from being inserted, cause single-stepping to fail, or
1284 even crash your program, if you disable after breakpoints have been
1285 inserted. However, GDB should not crash.
1287 set record memory-query on|off
1288 show record memory-query
1289 Control whether to stop the inferior if memory changes caused
1290 by an instruction cannot be recorded.
1295 The disassemble command now supports "start,+length" form of two arguments.
1299 ** GDB now provides a new directory location, called the python directory,
1300 where Python scripts written for GDB can be installed. The location
1301 of that directory is <data-directory>/python, where <data-directory>
1302 is the GDB data directory. For more details, see section `Scripting
1303 GDB using Python' in the manual.
1305 ** The GDB Python API now has access to breakpoints, symbols, symbol
1306 tables, program spaces, inferiors, threads and frame's code blocks.
1307 Additionally, GDB Parameters can now be created from the API, and
1308 manipulated via set/show in the CLI.
1310 ** New functions gdb.target_charset, gdb.target_wide_charset,
1311 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1313 ** New exception gdb.GdbError.
1315 ** Pretty-printers are now also looked up in the current program space.
1317 ** Pretty-printers can now be individually enabled and disabled.
1319 ** GDB now looks for names of Python scripts to auto-load in a
1320 special section named `.debug_gdb_scripts', in addition to looking
1321 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1323 * Tracepoint actions were unified with breakpoint commands. In particular,
1324 there are no longer differences in "info break" output for breakpoints and
1325 tracepoints and the "commands" command can be used for both tracepoints and
1326 regular breakpoints.
1330 ARM Symbian arm*-*-symbianelf*
1332 * D language support.
1333 GDB now supports debugging programs written in the D programming
1336 * GDB now supports the extended ptrace interface for PowerPC which is
1337 available since Linux kernel version 2.6.34. This automatically enables
1338 any hardware breakpoints and additional hardware watchpoints available in
1339 the processor. The old ptrace interface exposes just one hardware
1340 watchpoint and no hardware breakpoints.
1342 * GDB is now able to use the Data Value Compare (DVC) register available on
1343 embedded PowerPC processors to implement in hardware simple watchpoint
1344 conditions of the form:
1346 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1348 This works in native GDB running on Linux kernels with the extended ptrace
1349 interface mentioned above.
1351 *** Changes in GDB 7.1
1355 ** Namespace Support
1357 GDB now supports importing of namespaces in C++. This enables the
1358 user to inspect variables from imported namespaces. Support for
1359 namepace aliasing has also been added. So, if a namespace is
1360 aliased in the current scope (e.g. namepace C=A; ) the user can
1361 print variables using the alias (e.g. (gdb) print C::x).
1365 All known bugs relating to the printing of virtual base class were
1366 fixed. It is now possible to call overloaded static methods using a
1371 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1372 and reinterpret_cast<> are now handled by the C++ expression parser.
1376 Xilinx MicroBlaze microblaze-*-*
1381 Xilinx MicroBlaze microblaze
1384 * Multi-program debugging.
1386 GDB now has support for multi-program (a.k.a. multi-executable or
1387 multi-exec) debugging. This allows for debugging multiple inferiors
1388 simultaneously each running a different program under the same GDB
1389 session. See "Debugging Multiple Inferiors and Programs" in the
1390 manual for more information. This implied some user visible changes
1391 in the multi-inferior support. For example, "info inferiors" now
1392 lists inferiors that are not running yet or that have exited
1393 already. See also "New commands" and "New options" below.
1395 * New tracing features
1397 GDB's tracepoint facility now includes several new features:
1399 ** Trace state variables
1401 GDB tracepoints now include support for trace state variables, which
1402 are variables managed by the target agent during a tracing
1403 experiment. They are useful for tracepoints that trigger each
1404 other, so for instance one tracepoint can count hits in a variable,
1405 and then a second tracepoint has a condition that is true when the
1406 count reaches a particular value. Trace state variables share the
1407 $-syntax of GDB convenience variables, and can appear in both
1408 tracepoint actions and condition expressions. Use the "tvariable"
1409 command to create, and "info tvariables" to view; see "Trace State
1410 Variables" in the manual for more detail.
1414 GDB now includes an option for defining fast tracepoints, which
1415 targets may implement more efficiently, such as by installing a jump
1416 into the target agent rather than a trap instruction. The resulting
1417 speedup can be by two orders of magnitude or more, although the
1418 tradeoff is that some program locations on some target architectures
1419 might not allow fast tracepoint installation, for instance if the
1420 instruction to be replaced is shorter than the jump. To request a
1421 fast tracepoint, use the "ftrace" command, with syntax identical to
1422 the regular trace command.
1424 ** Disconnected tracing
1426 It is now possible to detach GDB from the target while it is running
1427 a trace experiment, then reconnect later to see how the experiment
1428 is going. In addition, a new variable disconnected-tracing lets you
1429 tell the target agent whether to continue running a trace if the
1430 connection is lost unexpectedly.
1434 GDB now has the ability to save the trace buffer into a file, and
1435 then use that file as a target, similarly to you can do with
1436 corefiles. You can select trace frames, print data that was
1437 collected in them, and use tstatus to display the state of the
1438 tracing run at the moment that it was saved. To create a trace
1439 file, use "tsave <filename>", and to use it, do "target tfile
1442 ** Circular trace buffer
1444 You can ask the target agent to handle the trace buffer as a
1445 circular buffer, discarding the oldest trace frames to make room for
1446 newer ones, by setting circular-trace-buffer to on. This feature may
1447 not be available for all target agents.
1452 The disassemble command, when invoked with two arguments, now requires
1453 the arguments to be comma-separated.
1456 The info variables command now displays variable definitions. Files
1457 which only declare a variable are not shown.
1460 The source command is now capable of sourcing Python scripts.
1461 This feature is dependent on the debugger being build with Python
1464 Related to this enhancement is also the introduction of a new command
1465 "set script-extension" (see below).
1467 * New commands (for set/show, see "New options" below)
1469 record save [<FILENAME>]
1470 Save a file (in core file format) containing the process record
1471 execution log for replay debugging at a later time.
1473 record restore <FILENAME>
1474 Restore the process record execution log that was saved at an
1475 earlier time, for replay debugging.
1477 add-inferior [-copies <N>] [-exec <FILENAME>]
1480 clone-inferior [-copies <N>] [ID]
1481 Make a new inferior ready to execute the same program another
1482 inferior has loaded.
1487 maint info program-spaces
1488 List the program spaces loaded into GDB.
1490 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1491 show remote interrupt-sequence
1492 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1493 as the sequence to the remote target in order to interrupt the execution.
1494 Ctrl-C is a default. Some system prefers BREAK which is high level of
1495 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1496 Magic SysRq g. It is BREAK signal and character 'g'.
1498 set remote interrupt-on-connect [on | off]
1499 show remote interrupt-on-connect
1500 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1501 remote target when gdb connects to it. This is needed when you debug
1504 set remotebreak [on | off]
1506 Deprecated. Use "set/show remote interrupt-sequence" instead.
1508 tvariable $NAME [ = EXP ]
1509 Create or modify a trace state variable.
1512 List trace state variables and their values.
1514 delete tvariable $NAME ...
1515 Delete one or more trace state variables.
1518 Evaluate the given expressions without collecting anything into the
1519 trace buffer. (Valid in tracepoint actions only.)
1521 ftrace FN / FILE:LINE / *ADDR
1522 Define a fast tracepoint at the given function, line, or address.
1524 * New expression syntax
1526 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1527 GDB now parses 0b101010 identically with 42.
1531 set follow-exec-mode new|same
1532 show follow-exec-mode
1533 Control whether GDB reuses the same inferior across an exec call or
1534 creates a new one. This is useful to be able to restart the old
1535 executable after the inferior having done an exec call.
1537 set default-collect EXPR, ...
1538 show default-collect
1539 Define a list of expressions to be collected at each tracepoint.
1540 This is a useful way to ensure essential items are not overlooked,
1541 such as registers or a critical global variable.
1543 set disconnected-tracing
1544 show disconnected-tracing
1545 If set to 1, the target is instructed to continue tracing if it
1546 loses its connection to GDB. If 0, the target is to stop tracing
1549 set circular-trace-buffer
1550 show circular-trace-buffer
1551 If set to on, the target is instructed to use a circular trace buffer
1552 and discard the oldest trace frames instead of stopping the trace due
1553 to a full trace buffer. If set to off, the trace stops when the buffer
1554 fills up. Some targets may not support this.
1556 set script-extension off|soft|strict
1557 show script-extension
1558 If set to "off", the debugger does not perform any script language
1559 recognition, and all sourced files are assumed to be GDB scripts.
1560 If set to "soft" (the default), files are sourced according to
1561 filename extension, falling back to GDB scripts if the first
1563 If set to "strict", files are sourced according to filename extension.
1565 set ada trust-PAD-over-XVS on|off
1566 show ada trust-PAD-over-XVS
1567 If off, activate a workaround against a bug in the debugging information
1568 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1569 the GCC sources for more information about the GNAT encoding and
1570 PAD types in particular). It is always safe to set this option to
1571 off, but this introduces a slight performance penalty. The default
1574 * Python API Improvements
1576 ** GDB provides the new class gdb.LazyString. This is useful in
1577 some pretty-printing cases. The new method gdb.Value.lazy_string
1578 provides a simple way to create objects of this type.
1580 ** The fields returned by gdb.Type.fields now have an
1581 `is_base_class' attribute.
1583 ** The new method gdb.Type.range returns the range of an array type.
1585 ** The new method gdb.parse_and_eval can be used to parse and
1586 evaluate an expression.
1588 * New remote packets
1591 Define a trace state variable.
1594 Get the current value of a trace state variable.
1597 Set desired tracing behavior upon disconnection.
1600 Set the trace buffer to be linear or circular.
1603 Get data about the tracepoints currently in use.
1607 Process record now works correctly with hardware watchpoints.
1609 Multiple bug fixes have been made to the mips-irix port, making it
1610 much more reliable. In particular:
1611 - Debugging threaded applications is now possible again. Previously,
1612 GDB would hang while starting the program, or while waiting for
1613 the program to stop at a breakpoint.
1614 - Attaching to a running process no longer hangs.
1615 - An error occurring while loading a core file has been fixed.
1616 - Changing the value of the PC register now works again. This fixes
1617 problems observed when using the "jump" command, or when calling
1618 a function from GDB, or even when assigning a new value to $pc.
1619 - With the "finish" and "return" commands, the return value for functions
1620 returning a small array is now correctly printed.
1621 - It is now possible to break on shared library code which gets executed
1622 during a shared library init phase (code executed while executing
1623 their .init section). Previously, the breakpoint would have no effect.
1624 - GDB is now able to backtrace through the signal handler for
1625 non-threaded programs.
1627 PIE (Position Independent Executable) programs debugging is now supported.
1628 This includes debugging execution of PIC (Position Independent Code) shared
1629 libraries although for that, it should be possible to run such libraries as an
1632 *** Changes in GDB 7.0
1634 * GDB now has an interface for JIT compilation. Applications that
1635 dynamically generate code can create symbol files in memory and register
1636 them with GDB. For users, the feature should work transparently, and
1637 for JIT developers, the interface is documented in the GDB manual in the
1638 "JIT Compilation Interface" chapter.
1640 * Tracepoints may now be conditional. The syntax is as for
1641 breakpoints; either an "if" clause appended to the "trace" command,
1642 or the "condition" command is available. GDB sends the condition to
1643 the target for evaluation using the same bytecode format as is used
1644 for tracepoint actions.
1646 * The disassemble command now supports: an optional /r modifier, print the
1647 raw instructions in hex as well as in symbolic form, and an optional /m
1648 modifier to print mixed source+assembly.
1650 * Process record and replay
1652 In a architecture environment that supports ``process record and
1653 replay'', ``process record and replay'' target can record a log of
1654 the process execution, and replay it with both forward and reverse
1657 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1658 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1659 set execution-direction {forward|reverse}, for targets that support
1662 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1663 feature is available with a native GDB running on kernel version
1666 * GDB now has support for multi-byte and wide character sets on the
1667 target. Strings whose character type is wchar_t, char16_t, or
1668 char32_t are now correctly printed. GDB supports wide- and unicode-
1669 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1670 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1671 `printf'. This feature requires iconv to work properly; if your
1672 system does not have a working iconv, GDB can use GNU libiconv. See
1673 the installation instructions for more information.
1675 * GDB now supports automatic retrieval of shared library files from
1676 remote targets. To use this feature, specify a system root that begins
1677 with the `remote:' prefix, either via the `set sysroot' command or via
1678 the `--with-sysroot' configure-time option.
1680 * "info sharedlibrary" now takes an optional regex of libraries to show,
1681 and it now reports if a shared library has no debugging information.
1683 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1684 now complete on file names.
1686 * When completing in expressions, gdb will attempt to limit
1687 completions to allowable structure or union fields, where appropriate.
1688 For instance, consider:
1690 # struct example { int f1; double f2; };
1691 # struct example variable;
1694 If the user types TAB at the end of this command line, the available
1695 completions will be "f1" and "f2".
1697 * Inlined functions are now supported. They show up in backtraces, and
1698 the "step", "next", and "finish" commands handle them automatically.
1700 * GDB now supports the token-splicing (##) and stringification (#)
1701 operators when expanding macros. It also supports variable-arity
1704 * GDB now supports inspecting extra signal information, exported by
1705 the new $_siginfo convenience variable. The feature is currently
1706 implemented on linux ARM, i386 and amd64.
1708 * GDB can now display the VFP floating point registers and NEON vector
1709 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1710 can provide these registers (requires Linux 2.6.30 or later). Remote
1711 and simulator targets may also provide them.
1713 * New remote packets
1716 Search memory for a sequence of bytes.
1719 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1720 operation over reliable transport links. Use of this packet is
1721 controlled by the `set remote noack-packet' command.
1724 Kill the process with the specified process ID. Use this in preference
1725 to `k' when multiprocess protocol extensions are supported.
1728 Obtains additional operating system information
1732 Read or write additional signal information.
1734 * Removed remote protocol undocumented extension
1736 An undocumented extension to the remote protocol's `S' stop reply
1737 packet that permited the stub to pass a process id was removed.
1738 Remote servers should use the `T' stop reply packet instead.
1740 * GDB now supports multiple function calling conventions according to the
1741 DWARF-2 DW_AT_calling_convention function attribute.
1743 * The SH target utilizes the aforementioned change to distinguish between gcc
1744 and Renesas calling convention. It also adds the new CLI commands
1745 `set/show sh calling-convention'.
1747 * GDB can now read compressed debug sections, as produced by GNU gold
1748 with the --compress-debug-sections=zlib flag.
1750 * 64-bit core files are now supported on AIX.
1752 * Thread switching is now supported on Tru64.
1754 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1755 which will be allocated using malloc later in program execution.
1757 * The qXfer:libraries:read remote procotol packet now allows passing a
1758 list of section offsets.
1760 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1761 conditions handling signals delivered during attach or thread creation
1762 have also been fixed.
1764 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1765 From the user's standpoint, all unqualified instances of True and False
1766 are treated as the standard definitions, regardless of context.
1768 * GDB now parses C++ symbol and type names more flexibly. For
1771 template<typename T> class C { };
1774 GDB will now correctly handle all of:
1776 ptype C<char const *>
1777 ptype C<char const*>
1778 ptype C<const char *>
1779 ptype C<const char*>
1781 * New features in the GDB remote stub, gdbserver
1783 - The "--wrapper" command-line argument tells gdbserver to use a
1784 wrapper program to launch programs for debugging.
1786 - On PowerPC and S/390 targets, it is now possible to use a single
1787 gdbserver executable to debug both 32-bit and 64-bit programs.
1788 (This requires gdbserver itself to be built as a 64-bit executable.)
1790 - gdbserver uses the new noack protocol mode for TCP connections to
1791 reduce communications latency, if also supported and enabled in GDB.
1793 - Support for the sparc64-linux-gnu target is now included in
1796 - The amd64-linux build of gdbserver now supports debugging both
1797 32-bit and 64-bit programs.
1799 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1800 now support hardware watchpoints, and will use them automatically
1805 GDB now has support for scripting using Python. Whether this is
1806 available is determined at configure time.
1808 New GDB commands can now be written in Python.
1810 * Ada tasking support
1812 Ada tasks can now be inspected in GDB. The following commands have
1816 Print the list of Ada tasks.
1818 Print detailed information about task number N.
1820 Print the task number of the current task.
1822 Switch the context of debugging to task number N.
1824 * Support for user-defined prefixed commands. The "define" command can
1825 add new commands to existing prefixes, e.g. "target".
1827 * Multi-inferior, multi-process debugging.
1829 GDB now has generalized support for multi-inferior debugging. See
1830 "Debugging Multiple Inferiors" in the manual for more information.
1831 Although availability still depends on target support, the command
1832 set is more uniform now. The GNU/Linux specific multi-forks support
1833 has been migrated to this new framework. This implied some user
1834 visible changes; see "New commands" and also "Removed commands"
1837 * Target descriptions can now describe the target OS ABI. See the
1838 "Target Description Format" section in the user manual for more
1841 * Target descriptions can now describe "compatible" architectures
1842 to indicate that the target can execute applications for a different
1843 architecture in addition to those for the main target architecture.
1844 See the "Target Description Format" section in the user manual for
1847 * Multi-architecture debugging.
1849 GDB now includes general supports for debugging applications on
1850 hybrid systems that use more than one single processor architecture
1851 at the same time. Each such hybrid architecture still requires
1852 specific support to be added. The only hybrid architecture supported
1853 in this version of GDB is the Cell Broadband Engine.
1855 * GDB now supports integrated debugging of Cell/B.E. applications that
1856 use both the PPU and SPU architectures. To enable support for hybrid
1857 Cell/B.E. debugging, you need to configure GDB to support both the
1858 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1859 --enable-targets configure option.
1861 * Non-stop mode debugging.
1863 For some targets, GDB now supports an optional mode of operation in
1864 which you can examine stopped threads while other threads continue
1865 to execute freely. This is referred to as non-stop mode, with the
1866 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1867 section in the user manual for more information.
1869 To be able to support remote non-stop debugging, a remote stub needs
1870 to implement the non-stop mode remote protocol extensions, as
1871 described in the "Remote Non-Stop" section of the user manual. The
1872 GDB remote stub, gdbserver, has been adjusted to support these
1873 extensions on linux targets.
1875 * New commands (for set/show, see "New options" below)
1877 catch syscall [NAME(S) | NUMBER(S)]
1878 Catch system calls. Arguments, which should be names of system
1879 calls or their numbers, mean catch only those syscalls. Without
1880 arguments, every syscall will be caught. When the inferior issues
1881 any of the specified syscalls, GDB will stop and announce the system
1882 call, both when it is called and when its call returns. This
1883 feature is currently available with a native GDB running on the
1884 Linux Kernel, under the following architectures: x86, x86_64,
1885 PowerPC and PowerPC64.
1887 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1889 Search memory for a sequence of bytes.
1891 maint set python print-stack
1892 maint show python print-stack
1893 Show a stack trace when an error is encountered in a Python script.
1896 Invoke CODE by passing it to the Python interpreter.
1901 These allow macros to be defined, undefined, and listed
1905 Show operating system information about processes.
1908 List the inferiors currently under GDB's control.
1911 Switch focus to inferior number NUM.
1914 Detach from inferior number NUM.
1917 Kill inferior number NUM.
1921 set spu stop-on-load
1922 show spu stop-on-load
1923 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1925 set spu auto-flush-cache
1926 show spu auto-flush-cache
1927 Control whether to automatically flush the software-managed cache
1928 during Cell/B.E. debugging.
1930 set sh calling-convention
1931 show sh calling-convention
1932 Control the calling convention used when calling SH target functions.
1935 show debug timestamp
1936 Control display of timestamps with GDB debugging output.
1938 set disassemble-next-line
1939 show disassemble-next-line
1940 Control display of disassembled source lines or instructions when
1943 set remote noack-packet
1944 show remote noack-packet
1945 Set/show the use of remote protocol QStartNoAckMode packet. See above
1946 under "New remote packets."
1948 set remote query-attached-packet
1949 show remote query-attached-packet
1950 Control use of remote protocol `qAttached' (query-attached) packet.
1952 set remote read-siginfo-object
1953 show remote read-siginfo-object
1954 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1957 set remote write-siginfo-object
1958 show remote write-siginfo-object
1959 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1962 set remote reverse-continue
1963 show remote reverse-continue
1964 Control use of remote protocol 'bc' (reverse-continue) packet.
1966 set remote reverse-step
1967 show remote reverse-step
1968 Control use of remote protocol 'bs' (reverse-step) packet.
1970 set displaced-stepping
1971 show displaced-stepping
1972 Control displaced stepping mode. Displaced stepping is a way to
1973 single-step over breakpoints without removing them from the debuggee.
1974 Also known as "out-of-line single-stepping".
1977 show debug displaced
1978 Control display of debugging info for displaced stepping.
1980 maint set internal-error
1981 maint show internal-error
1982 Control what GDB does when an internal error is detected.
1984 maint set internal-warning
1985 maint show internal-warning
1986 Control what GDB does when an internal warning is detected.
1991 Use a wrapper program to launch programs for debugging.
1993 set multiple-symbols (all|ask|cancel)
1994 show multiple-symbols
1995 The value of this variable can be changed to adjust the debugger behavior
1996 when an expression or a breakpoint location contains an ambiguous symbol
1997 name (an overloaded function name, for instance).
1999 set breakpoint always-inserted
2000 show breakpoint always-inserted
2001 Keep breakpoints always inserted in the target, as opposed to inserting
2002 them when resuming the target, and removing them when the target stops.
2003 This option can improve debugger performance on slow remote targets.
2005 set arm fallback-mode (arm|thumb|auto)
2006 show arm fallback-mode
2007 set arm force-mode (arm|thumb|auto)
2009 These commands control how ARM GDB determines whether instructions
2010 are ARM or Thumb. The default for both settings is auto, which uses
2011 the current CPSR value for instructions without symbols; previous
2012 versions of GDB behaved as if "set arm fallback-mode arm".
2014 set disable-randomization
2015 show disable-randomization
2016 Standalone programs run with the virtual address space randomization enabled
2017 by default on some platforms. This option keeps the addresses stable across
2018 multiple debugging sessions.
2022 Control whether other threads are stopped or not when some thread hits
2027 Requests that asynchronous execution is enabled in the target, if available.
2028 In this case, it's possible to resume target in the background, and interact
2029 with GDB while the target is running. "show target-async" displays the
2030 current state of asynchronous execution of the target.
2032 set target-wide-charset
2033 show target-wide-charset
2034 The target-wide-charset is the name of the character set that GDB
2035 uses when printing characters whose type is wchar_t.
2037 set tcp auto-retry (on|off)
2039 set tcp connect-timeout
2040 show tcp connect-timeout
2041 These commands allow GDB to retry failed TCP connections to a remote stub
2042 with a specified timeout period; this is useful if the stub is launched
2043 in parallel with GDB but may not be ready to accept connections immediately.
2045 set libthread-db-search-path
2046 show libthread-db-search-path
2047 Control list of directories which GDB will search for appropriate
2050 set schedule-multiple (on|off)
2051 show schedule-multiple
2052 Allow GDB to resume all threads of all processes or only threads of
2053 the current process.
2057 Use more aggressive caching for accesses to the stack. This improves
2058 performance of remote debugging (particularly backtraces) without
2059 affecting correctness.
2061 set interactive-mode (on|off|auto)
2062 show interactive-mode
2063 Control whether GDB runs in interactive mode (on) or not (off).
2064 When in interactive mode, GDB waits for the user to answer all
2065 queries. Otherwise, GDB does not wait and assumes the default
2066 answer. When set to auto (the default), GDB determines which
2067 mode to use based on the stdin settings.
2072 For program forks, this is replaced by the new more generic `info
2073 inferiors' command. To list checkpoints, you can still use the
2074 `info checkpoints' command, which was an alias for the `info forks'
2078 Replaced by the new `inferior' command. To switch between
2079 checkpoints, you can still use the `restart' command, which was an
2080 alias for the `fork' command.
2083 This is removed, since some targets don't have a notion of
2084 processes. To switch between processes, you can still use the
2085 `inferior' command using GDB's own inferior number.
2088 For program forks, this is replaced by the new more generic `kill
2089 inferior' command. To delete a checkpoint, you can still use the
2090 `delete checkpoint' command, which was an alias for the `delete
2094 For program forks, this is replaced by the new more generic `detach
2095 inferior' command. To detach a checkpoint, you can still use the
2096 `detach checkpoint' command, which was an alias for the `detach
2099 * New native configurations
2101 x86/x86_64 Darwin i[34567]86-*-darwin*
2103 x86_64 MinGW x86_64-*-mingw*
2107 Lattice Mico32 lm32-*
2108 x86 DICOS i[34567]86-*-dicos*
2109 x86_64 DICOS x86_64-*-dicos*
2112 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2113 (mingw32ce) debugging.
2119 These commands were actually not implemented on any target.
2121 *** Changes in GDB 6.8
2123 * New native configurations
2125 NetBSD/hppa hppa*-*netbsd*
2126 Xtensa GNU/Linux xtensa*-*-linux*
2130 NetBSD/hppa hppa*-*-netbsd*
2131 Xtensa GNU/Lunux xtensa*-*-linux*
2133 * Change in command line behavior -- corefiles vs. process ids.
2135 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2136 attaching to process NUMBER fails, GDB no longer attempts to open a
2137 core file named NUMBER. Attaching to a program using the -c option
2138 is no longer supported. Instead, use the '-p' or '--pid' options.
2140 * GDB can now be built as a native debugger for debugging Windows x86
2141 (mingw32) Portable Executable (PE) programs.
2143 * Pending breakpoints no longer change their number when their address
2146 * GDB now supports breakpoints with multiple locations,
2147 including breakpoints on C++ constructors, inside C++ templates,
2148 and in inlined functions.
2150 * GDB's ability to debug optimized code has been improved. GDB more
2151 accurately identifies function bodies and lexical blocks that occupy
2152 more than one contiguous range of addresses.
2154 * Target descriptions can now describe registers for PowerPC.
2156 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2157 registers on PowerPC targets.
2159 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2160 targets even when the libthread_db library is not available.
2162 * The GDB remote stub, gdbserver, now supports the new file transfer
2163 commands (remote put, remote get, and remote delete).
2165 * The GDB remote stub, gdbserver, now supports run and attach in
2166 extended-remote mode.
2168 * hppa*64*-*-hpux11* target broken
2169 The debugger is unable to start a program and fails with the following
2170 error: "Error trying to get information about dynamic linker".
2171 The gdb-6.7 release is also affected.
2173 * GDB now supports the --enable-targets= configure option to allow
2174 building a single GDB executable that supports multiple remote
2175 target architectures.
2177 * GDB now supports debugging C and C++ programs which use the
2178 Decimal Floating Point extension. In addition, the PowerPC target
2179 now has a set of pseudo-registers to inspect decimal float values
2180 stored in two consecutive float registers.
2182 * The -break-insert MI command can optionally create pending
2185 * Improved support for debugging Ada
2186 Many improvements to the Ada language support have been made. These
2188 - Better support for Ada2005 interface types
2189 - Improved handling of arrays and slices in general
2190 - Better support for Taft-amendment types
2191 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2193 - Improved command completion in Ada
2196 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2201 set print frame-arguments (all|scalars|none)
2202 show print frame-arguments
2203 The value of this variable can be changed to control which argument
2204 values should be printed by the debugger when displaying a frame.
2209 Transfer files to and from a remote target, and delete remote files.
2216 Transfer files to and from a remote target, and delete remote files.
2218 * New remote packets
2225 Open, close, read, write, and delete files on the remote system.
2228 Attach to an existing process on the remote system, in extended-remote
2232 Run a new process on the remote system, in extended-remote mode.
2234 *** Changes in GDB 6.7
2236 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2237 bfd, libiberty and opcodes, as revealed by static analysis donated by
2238 Coverity, Inc. (http://scan.coverity.com).
2240 * When looking up multiply-defined global symbols, GDB will now prefer the
2241 symbol definition in the current shared library if it was built using the
2242 -Bsymbolic linker option.
2244 * When the Text User Interface (TUI) is not configured, GDB will now
2245 recognize the -tui command-line option and print a message that the TUI
2248 * The GDB remote stub, gdbserver, now has lower overhead for high
2249 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2251 * GDB for MIPS targets now autodetects whether a remote target provides
2252 32-bit or 64-bit register values.
2254 * Support for C++ member pointers has been improved.
2256 * GDB now understands XML target descriptions, which specify the
2257 target's overall architecture. GDB can read a description from
2258 a local file or over the remote serial protocol.
2260 * Vectors of single-byte data use a new integer type which is not
2261 automatically displayed as character or string data.
2263 * The /s format now works with the print command. It displays
2264 arrays of single-byte integers and pointers to single-byte integers
2267 * Target descriptions can now describe target-specific registers,
2268 for architectures which have implemented the support (currently
2269 only ARM, M68K, and MIPS).
2271 * GDB and the GDB remote stub, gdbserver, now support the XScale
2274 * The GDB remote stub, gdbserver, has been updated to support
2275 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2276 has been rewritten to use the standard GDB remote protocol.
2278 * GDB can now step into C++ functions which are called through thunks.
2280 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2282 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2283 layout. It also supports a TextSeg= and DataSeg= response when only
2284 segment base addresses (rather than offsets) are available.
2286 * The /i format now outputs any trailing branch delay slot instructions
2287 immediately following the last instruction within the count specified.
2289 * The GDB remote protocol "T" stop reply packet now supports a
2290 "library" response. Combined with the new "qXfer:libraries:read"
2291 packet, this response allows GDB to debug shared libraries on targets
2292 where the operating system manages the list of loaded libraries (e.g.
2293 Windows and SymbianOS).
2295 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2296 (DLLs) on Windows and Windows CE targets.
2298 * GDB now supports a faster verification that a .debug file matches its binary
2299 according to its build-id signature, if the signature is present.
2305 Enable or disable hardware flow control (RTS/CTS) on the serial port
2306 when debugging using remote targets.
2308 set mem inaccessible-by-default
2309 show mem inaccessible-by-default
2310 If the target supplies a memory map, for instance via the remote
2311 protocol's "qXfer:memory-map:read" packet, setting this variable
2312 prevents GDB from accessing memory outside the memory map. This
2313 is useful for targets with memory mapped registers or which react
2314 badly to accesses of unmapped address space.
2316 set breakpoint auto-hw
2317 show breakpoint auto-hw
2318 If the target supplies a memory map, for instance via the remote
2319 protocol's "qXfer:memory-map:read" packet, setting this variable
2320 lets GDB use hardware breakpoints automatically for memory regions
2321 where it can not use software breakpoints. This covers both the
2322 "break" command and internal breakpoints used for other commands
2323 including "next" and "finish".
2326 catch exception unhandled
2327 Stop the program execution when Ada exceptions are raised.
2330 Stop the program execution when an Ada assertion failed.
2334 Set an alternate system root for target files. This is a more
2335 general version of "set solib-absolute-prefix", which is now
2336 an alias to "set sysroot".
2339 Provide extended SPU facility status information. This set of
2340 commands is available only when debugging the Cell/B.E. SPU
2343 * New native configurations
2345 OpenBSD/sh sh*-*openbsd*
2348 unset tdesc filename
2350 Use the specified local file as an XML target description, and do
2351 not query the target for its built-in description.
2355 OpenBSD/sh sh*-*-openbsd*
2356 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2357 Toshiba Media Processor mep-elf
2359 * New remote packets
2362 Ignore the specified signals; pass them directly to the debugged program
2363 without stopping other threads or reporting them to GDB.
2365 qXfer:features:read:
2366 Read an XML target description from the target, which describes its
2371 Read or write contents of an spufs file on the target system. These
2372 packets are available only on the Cell/B.E. SPU architecture.
2374 qXfer:libraries:read:
2375 Report the loaded shared libraries. Combined with new "T" packet
2376 response, this packet allows GDB to debug shared libraries on
2377 targets where the operating system manages the list of loaded
2378 libraries (e.g. Windows and SymbianOS).
2382 Support for these obsolete configurations has been removed.
2390 i[34567]86-*-lynxos*
2391 i[34567]86-*-netware*
2392 i[34567]86-*-sco3.2v5*
2393 i[34567]86-*-sco3.2v4*
2395 i[34567]86-*-sysv4.2*
2398 i[34567]86-*-unixware2*
2399 i[34567]86-*-unixware*
2408 * Other removed features
2415 Various m68k-only ROM monitors.
2422 Various Renesas ROM monitors and debugging interfaces for SH and
2427 Support for a Macraigor serial interface to on-chip debugging.
2428 GDB does not directly support the newer parallel or USB
2433 A debug information format. The predecessor to DWARF 2 and
2434 DWARF 3, which are still supported.
2436 Support for the HP aCC compiler on HP-UX/PA-RISC
2438 SOM-encapsulated symbolic debugging information, automatic
2439 invocation of pxdb, and the aCC custom C++ ABI. This does not
2440 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2441 with aCC can still be debugged on an assembly level.
2443 MIPS ".pdr" sections
2445 A MIPS-specific format used to describe stack frame layout
2446 in debugging information.
2450 GDB could work with an older version of Guile to debug
2451 the interpreter and Scheme programs running in it.
2453 set mips stack-arg-size
2454 set mips saved-gpreg-size
2456 Use "set mips abi" to control parameter passing for MIPS.
2458 *** Changes in GDB 6.6
2463 Cell Broadband Engine SPU spu-elf
2465 * GDB can now be configured as a cross-debugger targeting native Windows
2466 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2467 running on a Windows system over TCP/IP to debug Windows programs.
2469 * The GDB remote stub, gdbserver, has been updated to support Windows and
2470 Cygwin debugging. Both single-threaded and multi-threaded programs are
2473 * The "set trust-readonly-sections" command works again. This command was
2474 broken in GDB 6.3, 6.4, and 6.5.
2476 * The "load" command now supports writing to flash memory, if the remote
2477 stub provides the required support.
2479 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2480 longer requires symbolic debug information (e.g. DWARF-2).
2485 unset substitute-path
2486 show substitute-path
2487 Manage a list of substitution rules that GDB uses to rewrite the name
2488 of the directories where the sources are located. This can be useful
2489 for instance when the sources were moved to a different location
2490 between compilation and debugging.
2494 Print each CLI command as it is executed. Each command is prefixed with
2495 a number of `+' symbols representing the nesting depth.
2496 The source command now has a `-v' option to enable the same feature.
2500 The ARM Demon monitor support (RDP protocol, "target rdp").
2502 Kernel Object Display, an embedded debugging feature which only worked with
2503 an obsolete version of Cisco IOS.
2505 The 'set download-write-size' and 'show download-write-size' commands.
2507 * New remote packets
2510 Tell a stub about GDB client features, and request remote target features.
2511 The first feature implemented is PacketSize, which allows the target to
2512 specify the size of packets it can handle - to minimize the number of
2513 packets required and improve performance when connected to a remote
2517 Fetch an OS auxilliary vector from the remote stub. This packet is a
2518 more efficient replacement for qPart:auxv:read.
2520 qXfer:memory-map:read:
2521 Fetch a memory map from the remote stub, including information about
2522 RAM, ROM, and flash memory devices.
2527 Erase and program a flash memory device.
2529 * Removed remote packets
2532 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2533 used it, and only gdbserver implemented it.
2535 *** Changes in GDB 6.5
2539 Renesas M32C/M16C m32c-elf
2541 Morpho Technologies ms1 ms1-elf
2545 init-if-undefined Initialize a convenience variable, but
2546 only if it doesn't already have a value.
2548 The following commands are presently only implemented for native GNU/Linux:
2550 checkpoint Save a snapshot of the program state.
2552 restart <n> Return the program state to a
2553 previously saved state.
2555 info checkpoints List currently saved checkpoints.
2557 delete-checkpoint <n> Delete a previously saved checkpoint.
2559 set|show detach-on-fork Tell gdb whether to detach from a newly
2560 forked process, or to keep debugging it.
2562 info forks List forks of the user program that
2563 are available to be debugged.
2565 fork <n> Switch to debugging one of several
2566 forks of the user program that are
2567 available to be debugged.
2569 delete-fork <n> Delete a fork from the list of forks
2570 that are available to be debugged (and
2571 kill the forked process).
2573 detach-fork <n> Delete a fork from the list of forks
2574 that are available to be debugged (and
2575 allow the process to continue).
2579 Morpho Technologies ms2 ms1-elf
2581 * Improved Windows host support
2583 GDB now builds as a cross debugger hosted on i686-mingw32, including
2584 native console support, and remote communications using either
2585 network sockets or serial ports.
2587 * Improved Modula-2 language support
2589 GDB can now print most types in the Modula-2 syntax. This includes:
2590 basic types, set types, record types, enumerated types, range types,
2591 pointer types and ARRAY types. Procedure var parameters are correctly
2592 printed and hexadecimal addresses and character constants are also
2593 written in the Modula-2 syntax. Best results can be obtained by using
2594 GNU Modula-2 together with the -gdwarf-2 command line option.
2598 The ARM rdi-share module.
2600 The Netware NLM debug server.
2602 *** Changes in GDB 6.4
2604 * New native configurations
2606 OpenBSD/arm arm*-*-openbsd*
2607 OpenBSD/mips64 mips64-*-openbsd*
2611 Morpho Technologies ms1 ms1-elf
2613 * New command line options
2615 --batch-silent As for --batch, but totally silent.
2616 --return-child-result The debugger will exist with the same value
2617 the child (debugged) program exited with.
2618 --eval-command COMMAND, -ex COMMAND
2619 Execute a single GDB CLI command. This may be
2620 specified multiple times and in conjunction
2621 with the --command (-x) option.
2623 * Deprecated commands removed
2625 The following commands, that were deprecated in 2000, have been
2629 set|show arm disassembly-flavor set|show arm disassembler
2630 othernames set arm disassembler
2631 set|show remotedebug set|show debug remote
2632 set|show archdebug set|show debug arch
2633 set|show eventdebug set|show debug event
2636 * New BSD user-level threads support
2638 It is now possible to debug programs using the user-level threads
2639 library on OpenBSD and FreeBSD. Currently supported (target)
2642 FreeBSD/amd64 x86_64-*-freebsd*
2643 FreeBSD/i386 i386-*-freebsd*
2644 OpenBSD/i386 i386-*-openbsd*
2646 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2647 are not yet supported.
2649 * New support for Matsushita MN10300 w/sim added
2650 (Work in progress). mn10300-elf.
2652 * REMOVED configurations and files
2654 VxWorks and the XDR protocol *-*-vxworks
2655 Motorola MCORE mcore-*-*
2656 National Semiconductor NS32000 ns32k-*-*
2658 * New "set print array-indexes" command
2660 After turning this setting "on", GDB prints the index of each element
2661 when displaying arrays. The default is "off" to preserve the previous
2664 * VAX floating point support
2666 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2668 * User-defined command support
2670 In addition to using $arg0..$arg9 for argument passing, it is now possible
2671 to use $argc to determine now many arguments have been passed. See the
2672 section on user-defined commands in the user manual for more information.
2674 *** Changes in GDB 6.3:
2676 * New command line option
2678 GDB now accepts -l followed by a number to set the timeout for remote
2681 * GDB works with GCC -feliminate-dwarf2-dups
2683 GDB now supports a more compact representation of DWARF-2 debug
2684 information using DW_FORM_ref_addr references. These are produced
2685 by GCC with the option -feliminate-dwarf2-dups and also by some
2686 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2687 to use -feliminate-dwarf2-dups.
2689 * Internationalization
2691 When supported by the host system, GDB will be built with
2692 internationalization (libintl). The task of marking up the sources is
2693 continued, we're looking forward to our first translation.
2697 Initial support for debugging programs compiled with the GNAT
2698 implementation of the Ada programming language has been integrated
2699 into GDB. In this release, support is limited to expression evaluation.
2701 * New native configurations
2703 GNU/Linux/m32r m32r-*-linux-gnu
2707 GDB's remote protocol now includes support for the 'p' packet. This
2708 packet is used to fetch individual registers from a remote inferior.
2710 * END-OF-LIFE registers[] compatibility module
2712 GDB's internal register infrastructure has been completely rewritten.
2713 The new infrastructure making possible the implementation of key new
2714 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2717 GDB 6.3 will be the last release to include the the registers[]
2718 compatibility module that allowed out-of-date configurations to
2719 continue to work. This change directly impacts the following
2729 powerpc bdm protocol
2731 Unless there is activity to revive these configurations, they will be
2732 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2734 * OBSOLETE configurations and files
2736 Configurations that have been declared obsolete in this release have
2737 been commented out. Unless there is activity to revive these
2738 configurations, the next release of GDB will have their sources
2739 permanently REMOVED.
2748 *** Changes in GDB 6.2.1:
2750 * MIPS `break main; run' gave an heuristic-fence-post warning
2752 When attempting to run even a simple program, a warning about
2753 heuristic-fence-post being hit would be reported. This problem has
2756 * MIPS IRIX 'long double' crashed GDB
2758 When examining a long double variable, GDB would get a segmentation
2759 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2760 IRIX long double values).
2764 A bug in the VAX stack code was causing problems with the "next"
2765 command. This problem has been fixed.
2767 *** Changes in GDB 6.2:
2769 * Fix for ``many threads''
2771 On GNU/Linux systems that use the NPTL threads library, a program
2772 rapidly creating and deleting threads would confuse GDB leading to the
2775 ptrace: No such process.
2776 thread_db_get_info: cannot get thread info: generic error
2778 This problem has been fixed.
2780 * "-async" and "-noasync" options removed.
2782 Support for the broken "-noasync" option has been removed (it caused
2785 * New ``start'' command.
2787 This command runs the program until the begining of the main procedure.
2789 * New BSD Kernel Data Access Library (libkvm) interface
2791 Using ``target kvm'' it is now possible to debug kernel core dumps and
2792 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2793 platforms. Currently supported (native-only) configurations are:
2795 FreeBSD/amd64 x86_64-*-freebsd*
2796 FreeBSD/i386 i?86-*-freebsd*
2797 NetBSD/i386 i?86-*-netbsd*
2798 NetBSD/m68k m68*-*-netbsd*
2799 NetBSD/sparc sparc-*-netbsd*
2800 OpenBSD/amd64 x86_64-*-openbsd*
2801 OpenBSD/i386 i?86-*-openbsd*
2802 OpenBSD/m68k m68*-openbsd*
2803 OpenBSD/sparc sparc-*-openbsd*
2805 * Signal trampoline code overhauled
2807 Many generic problems with GDB's signal handling code have been fixed.
2808 These include: backtraces through non-contiguous stacks; recognition
2809 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2810 call; backtrace through a signal trampoline; step into and out of
2811 signal handlers; and single-stepping in the signal trampoline.
2813 Please note that kernel bugs are a limiting factor here. These
2814 features have been shown to work on an s390 GNU/Linux system that
2815 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2817 * Cygwin support for DWARF 2 added.
2819 * New native configurations
2821 GNU/Linux/hppa hppa*-*-linux*
2822 OpenBSD/hppa hppa*-*-openbsd*
2823 OpenBSD/m68k m68*-*-openbsd*
2824 OpenBSD/m88k m88*-*-openbsd*
2825 OpenBSD/powerpc powerpc-*-openbsd*
2826 NetBSD/vax vax-*-netbsd*
2827 OpenBSD/vax vax-*-openbsd*
2829 * END-OF-LIFE frame compatibility module
2831 GDB's internal frame infrastructure has been completely rewritten.
2832 The new infrastructure making it possible to support key new features
2833 including DWARF 2 Call Frame Information. To aid in the task of
2834 migrating old configurations to this new infrastructure, a
2835 compatibility module, that allowed old configurations to continue to
2836 work, was also included.
2838 GDB 6.2 will be the last release to include this frame compatibility
2839 module. This change directly impacts the following configurations:
2849 Unless there is activity to revive these configurations, they will be
2850 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2852 * REMOVED configurations and files
2854 Sun 3, running SunOS 3 m68*-*-sunos3*
2855 Sun 3, running SunOS 4 m68*-*-sunos4*
2856 Sun 2, running SunOS 3 m68000-*-sunos3*
2857 Sun 2, running SunOS 4 m68000-*-sunos4*
2858 Motorola 680x0 running LynxOS m68*-*-lynxos*
2859 AT&T 3b1/Unix pc m68*-att-*
2860 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2861 decstation mips-dec-* mips-little-*
2862 riscos mips-*-riscos* mips-*-sysv*
2863 sonymips mips-sony-*
2864 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2866 *** Changes in GDB 6.1.1:
2868 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2870 The TUI (Text-mode User Interface) is now built as part of a default
2871 GDB configuration. It is enabled by either selecting the TUI with the
2872 command line option "-i=tui" or by running the separate "gdbtui"
2873 program. For more information on the TUI, see the manual "Debugging
2876 * Pending breakpoint support (also included in GDB 6.1)
2878 Support has been added to allow you to specify breakpoints in shared
2879 libraries that have not yet been loaded. If a breakpoint location
2880 cannot be found, and the "breakpoint pending" option is set to auto,
2881 GDB queries you if you wish to make the breakpoint pending on a future
2882 shared-library load. If and when GDB resolves the breakpoint symbol,
2883 the pending breakpoint is removed as one or more regular breakpoints
2886 Pending breakpoints are very useful for GCJ Java debugging.
2888 * Fixed ISO-C build problems
2890 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2891 non ISO-C code that stopped them being built using a more strict ISO-C
2892 compiler (e.g., IBM's C compiler).
2894 * Fixed build problem on IRIX 5
2896 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2897 wasn't able to compile compile on an IRIX 5 system.
2899 * Added execute permission to gdb/gdbserver/configure
2901 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2902 permission. This bug would cause configure to fail on a number of
2903 systems (Solaris, IRIX). Ref: server/519.
2905 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2907 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2908 has been updated to use constant array sizes.
2910 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2912 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2913 its generated DWARF Call Frame Info. This encoding was causing GDB to
2914 panic, that panic has been fixed. Ref: gdb/1628.
2916 * Fixed a problem when examining parameters in shared library code.
2918 When examining parameters in optimized shared library code generated
2919 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2920 not available''. GDB now correctly displays the variable's value.
2922 *** Changes in GDB 6.1:
2924 * Removed --with-mmalloc
2926 Support for the mmalloc memory manager has been removed, as it
2927 conflicted with the internal gdb byte cache.
2929 * Changes in AMD64 configurations
2931 The AMD64 target now includes the %cs and %ss registers. As a result
2932 the AMD64 remote protocol has changed; this affects the floating-point
2933 and SSE registers. If you rely on those registers for your debugging,
2934 you should upgrade gdbserver on the remote side.
2936 * Revised SPARC target
2938 The SPARC target has been completely revised, incorporating the
2939 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2940 support for LynxOS and SunOS 4 has been dropped. Calling functions
2941 from within GDB on operating systems with a non-executable stack
2942 (Solaris, OpenBSD) now works.
2946 GDB has a new C++ demangler which does a better job on the mangled
2947 names generated by current versions of g++. It also runs faster, so
2948 with this and other changes gdb should now start faster on large C++
2951 * DWARF 2 Location Expressions
2953 GDB support for location expressions has been extended to support function
2954 arguments and frame bases. Older versions of GDB could crash when they
2957 * C++ nested types and namespaces
2959 GDB's support for nested types and namespaces in C++ has been
2960 improved, especially if you use the DWARF 2 debugging format. (This
2961 is the default for recent versions of GCC on most platforms.)
2962 Specifically, if you have a class "Inner" defined within a class or
2963 namespace "Outer", then GDB realizes that the class's name is
2964 "Outer::Inner", not simply "Inner". This should greatly reduce the
2965 frequency of complaints about not finding RTTI symbols. In addition,
2966 if you are stopped at inside of a function defined within a namespace,
2967 GDB modifies its name lookup accordingly.
2969 * New native configurations
2971 NetBSD/amd64 x86_64-*-netbsd*
2972 OpenBSD/amd64 x86_64-*-openbsd*
2973 OpenBSD/alpha alpha*-*-openbsd*
2974 OpenBSD/sparc sparc-*-openbsd*
2975 OpenBSD/sparc64 sparc64-*-openbsd*
2977 * New debugging protocols
2979 M32R with SDI protocol m32r-*-elf*
2981 * "set prompt-escape-char" command deleted.
2983 The command "set prompt-escape-char" has been deleted. This command,
2984 and its very obscure effet on GDB's prompt, was never documented,
2985 tested, nor mentioned in the NEWS file.
2987 * OBSOLETE configurations and files
2989 Configurations that have been declared obsolete in this release have
2990 been commented out. Unless there is activity to revive these
2991 configurations, the next release of GDB will have their sources
2992 permanently REMOVED.
2994 Sun 3, running SunOS 3 m68*-*-sunos3*
2995 Sun 3, running SunOS 4 m68*-*-sunos4*
2996 Sun 2, running SunOS 3 m68000-*-sunos3*
2997 Sun 2, running SunOS 4 m68000-*-sunos4*
2998 Motorola 680x0 running LynxOS m68*-*-lynxos*
2999 AT&T 3b1/Unix pc m68*-att-*
3000 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3001 decstation mips-dec-* mips-little-*
3002 riscos mips-*-riscos* mips-*-sysv*
3003 sonymips mips-sony-*
3004 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3006 * REMOVED configurations and files
3008 SGI Irix-4.x mips-sgi-irix4 or iris4
3009 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3010 Z8000 simulator z8k-zilog-none or z8ksim
3011 Matsushita MN10200 w/simulator mn10200-*-*
3012 H8/500 simulator h8500-hitachi-hms or h8500hms
3013 HP/PA running BSD hppa*-*-bsd*
3014 HP/PA running OSF/1 hppa*-*-osf*
3015 HP/PA Pro target hppa*-*-pro*
3016 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3017 386BSD i[3456]86-*-bsd*
3018 Sequent family i[3456]86-sequent-sysv4*
3019 i[3456]86-sequent-sysv*
3020 i[3456]86-sequent-bsd*
3021 SPARC running LynxOS sparc-*-lynxos*
3022 SPARC running SunOS 4 sparc-*-sunos4*
3023 Tsqware Sparclet sparclet-*-*
3024 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3026 *** Changes in GDB 6.0:
3030 Support for debugging the Objective-C programming language has been
3031 integrated into GDB.
3033 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3035 DWARF 2's Call Frame Information makes available compiler generated
3036 information that more exactly describes the program's run-time stack.
3037 By using this information, GDB is able to provide more robust stack
3040 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3041 have been updated to use a new backtrace mechanism which includes
3042 DWARF 2 CFI support.
3046 GDB's remote protocol has been extended to include support for hosted
3047 file I/O (where the remote target uses GDB's file system). See GDB's
3048 remote protocol documentation for details.
3050 * All targets using the new architecture framework.
3052 All of GDB's targets have been updated to use the new internal
3053 architecture framework. The way is now open for future GDB releases
3054 to include cross-architecture native debugging support (i386 on amd64,
3057 * GNU/Linux's Thread Local Storage (TLS)
3059 GDB now includes support for for the GNU/Linux implementation of
3060 per-thread variables.
3062 * GNU/Linux's Native POSIX Thread Library (NPTL)
3064 GDB's thread code has been updated to work with either the new
3065 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3067 * Separate debug info.
3069 GDB, in conjunction with BINUTILS, now supports a mechanism for
3070 automatically loading debug information from a separate file. Instead
3071 of shipping full debug and non-debug versions of system libraries,
3072 system integrators can now instead ship just the stripped libraries
3073 and optional debug files.
3075 * DWARF 2 Location Expressions
3077 DWARF 2 Location Expressions allow the compiler to more completely
3078 describe the location of variables (even in optimized code) to the
3081 GDB now includes preliminary support for location expressions (support
3082 for DW_OP_piece is still missing).
3086 A number of long standing bugs that caused GDB to die while starting a
3087 Java application have been fixed. GDB's Java support is now
3088 considered "useable".
3090 * GNU/Linux support for fork, vfork, and exec.
3092 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3093 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3096 * GDB supports logging output to a file
3098 There are two new commands, "set logging" and "show logging", which can be
3099 used to capture GDB's output to a file.
3101 * The meaning of "detach" has changed for gdbserver
3103 The "detach" command will now resume the application, as documented. To
3104 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3107 * d10v, m68hc11 `regs' command deprecated
3109 The `info registers' command has been updated so that it displays the
3110 registers using a format identical to the old `regs' command.
3114 A new command, "maint set profile on/off", has been added. This command can
3115 be used to enable or disable profiling while running GDB, to profile a
3116 session or a set of commands. In addition there is a new configure switch,
3117 "--enable-profiling", which will cause GDB to be compiled with profiling
3118 data, for more informative profiling results.
3120 * Default MI syntax changed to "mi2".
3122 The default MI (machine interface) syntax, enabled by the command line
3123 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3124 "mi1", can be enabled by specifying the option "-i=mi1".
3126 Support for the original "mi0" syntax (included in GDB 5.0) has been
3129 Fix for gdb/192: removed extraneous space when displaying frame level.
3130 Fix for gdb/672: update changelist is now output in mi list format.
3131 Fix for gdb/702: a -var-assign that updates the value now shows up
3132 in a subsequent -var-update.
3134 * New native configurations.
3136 FreeBSD/amd64 x86_64-*-freebsd*
3138 * Multi-arched targets.
3140 HP/PA HPUX11 hppa*-*-hpux*
3141 Renesas M32R/D w/simulator m32r-*-elf*
3143 * OBSOLETE configurations and files
3145 Configurations that have been declared obsolete in this release have
3146 been commented out. Unless there is activity to revive these
3147 configurations, the next release of GDB will have their sources
3148 permanently REMOVED.
3150 Z8000 simulator z8k-zilog-none or z8ksim
3151 Matsushita MN10200 w/simulator mn10200-*-*
3152 H8/500 simulator h8500-hitachi-hms or h8500hms
3153 HP/PA running BSD hppa*-*-bsd*
3154 HP/PA running OSF/1 hppa*-*-osf*
3155 HP/PA Pro target hppa*-*-pro*
3156 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3157 Sequent family i[3456]86-sequent-sysv4*
3158 i[3456]86-sequent-sysv*
3159 i[3456]86-sequent-bsd*
3160 Tsqware Sparclet sparclet-*-*
3161 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3163 * REMOVED configurations and files
3166 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3167 IBM AIX PS/2 i[3456]86-*-aix
3168 i386 running Mach 3.0 i[3456]86-*-mach3*
3169 i386 running Mach i[3456]86-*-mach*
3170 i386 running OSF/1 i[3456]86-*osf1mk*
3171 HP/Apollo 68k Family m68*-apollo*-sysv*,
3173 m68*-hp-bsd*, m68*-hp-hpux*
3174 Argonaut Risc Chip (ARC) arc-*-*
3175 Mitsubishi D30V d30v-*-*
3176 Fujitsu FR30 fr30-*-elf*
3177 OS/9000 i[34]86-*-os9k
3178 I960 with MON960 i960-*-coff
3180 * MIPS $fp behavior changed
3182 The convenience variable $fp, for the MIPS, now consistently returns
3183 the address of the current frame's base. Previously, depending on the
3184 context, $fp could refer to either $sp or the current frame's base
3185 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3186 The GNU Source-Level Debugger''.
3188 *** Changes in GDB 5.3:
3190 * GNU/Linux shared library multi-threaded performance improved.
3192 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3193 `/proc', in preference to `ptrace' for memory reads. This may result
3194 in an improvement in the start-up time of multi-threaded, shared
3195 library applications when run under GDB. One GDB user writes: ``loads
3196 shared libs like mad''.
3198 * ``gdbserver'' now supports multi-threaded applications on some targets
3200 Support for debugging multi-threaded applications which use
3201 the GNU/Linux LinuxThreads package has been added for
3202 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3203 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3205 * GDB now supports C/C++ preprocessor macros.
3207 GDB now expands preprocessor macro invocations in C/C++ expressions,
3208 and provides various commands for showing macro definitions and how
3211 The new command `macro expand EXPRESSION' expands any macro
3212 invocations in expression, and shows the result.
3214 The new command `show macro MACRO-NAME' shows the definition of the
3215 macro named MACRO-NAME, and where it was defined.
3217 Most compilers don't include information about macros in the debugging
3218 information by default. In GCC 3.1, for example, you need to compile
3219 your program with the options `-gdwarf-2 -g3'. If the macro
3220 information is present in the executable, GDB will read it.
3222 * Multi-arched targets.
3224 DEC Alpha (partial) alpha*-*-*
3225 DEC VAX (partial) vax-*-*
3227 National Semiconductor NS32000 (partial) ns32k-*-*
3228 Motorola 68000 (partial) m68k-*-*
3229 Motorola MCORE mcore-*-*
3233 Fujitsu FRV architecture added by Red Hat frv*-*-*
3236 * New native configurations
3238 Alpha NetBSD alpha*-*-netbsd*
3239 SH NetBSD sh*-*-netbsdelf*
3240 MIPS NetBSD mips*-*-netbsd*
3241 UltraSPARC NetBSD sparc64-*-netbsd*
3243 * OBSOLETE configurations and files
3245 Configurations that have been declared obsolete in this release have
3246 been commented out. Unless there is activity to revive these
3247 configurations, the next release of GDB will have their sources
3248 permanently REMOVED.
3250 Mitsubishi D30V d30v-*-*
3251 OS/9000 i[34]86-*-os9k
3252 IBM AIX PS/2 i[3456]86-*-aix
3253 Fujitsu FR30 fr30-*-elf*
3254 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3255 Argonaut Risc Chip (ARC) arc-*-*
3256 i386 running Mach 3.0 i[3456]86-*-mach3*
3257 i386 running Mach i[3456]86-*-mach*
3258 i386 running OSF/1 i[3456]86-*osf1mk*
3259 HP/Apollo 68k Family m68*-apollo*-sysv*,
3261 m68*-hp-bsd*, m68*-hp-hpux*
3262 I960 with MON960 i960-*-coff
3264 * OBSOLETE languages
3266 CHILL, a Pascal like language used by telecommunications companies.
3268 * REMOVED configurations and files
3270 AMD 29k family via UDI a29k-amd-udi, udi29k
3271 A29K VxWorks a29k-*-vxworks
3272 AMD 29000 embedded, using EBMON a29k-none-none
3273 AMD 29000 embedded with COFF a29k-none-coff
3274 AMD 29000 embedded with a.out a29k-none-aout
3276 testsuite/gdb.hp/gdb.threads-hp/ directory
3278 * New command "set max-user-call-depth <nnn>"
3280 This command allows the user to limit the call depth of user-defined
3281 commands. The default is 1024.
3283 * Changes in FreeBSD/i386 native debugging.
3285 Support for the "generate-core-file" has been added.
3287 * New commands "dump", "append", and "restore".
3289 These commands allow data to be copied from target memory
3290 to a bfd-format or binary file (dump and append), and back
3291 from a file into memory (restore).
3293 * Improved "next/step" support on multi-processor Alpha Tru64.
3295 The previous single-step mechanism could cause unpredictable problems,
3296 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3297 of a software single-step mechanism prevents this.
3299 *** Changes in GDB 5.2.1:
3307 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3308 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3309 Fix, by Joel Brobecker imported from mainline.
3311 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3312 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3313 Fix, by Fred Fish, imported from mainline.
3315 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3316 Surprisingly enough, it works now.
3317 By Michal Ludvig, imported from mainline.
3319 i386 hardware watchpoint support:
3320 avoid misses on second run for some targets.
3321 By Pierre Muller, imported from mainline.
3323 *** Changes in GDB 5.2:
3325 * New command "set trust-readonly-sections on[off]".
3327 This command is a hint that tells gdb that read-only sections
3328 really are read-only (ie. that their contents will not change).
3329 In this mode, gdb will go to the object file rather than the
3330 target to read memory from read-only sections (such as ".text").
3331 This can be a significant performance improvement on some
3332 (notably embedded) targets.
3334 * New command "generate-core-file" (or "gcore").
3336 This new gdb command allows the user to drop a core file of the child
3337 process state at any time. So far it's been implemented only for
3338 GNU/Linux and Solaris, but should be relatively easily ported to other
3339 hosts. Argument is core file name (defaults to core.<pid>).
3341 * New command line option
3343 GDB now accepts --pid or -p followed by a process id.
3345 * Change in command line behavior -- corefiles vs. process ids.
3347 There is a subtle behavior in the way in which GDB handles
3348 command line arguments. The first non-flag argument is always
3349 a program to debug, but the second non-flag argument may either
3350 be a corefile or a process id. Previously, GDB would attempt to
3351 open the second argument as a corefile, and if that failed, would
3352 issue a superfluous error message and then attempt to attach it as
3353 a process. Now, if the second argument begins with a non-digit,
3354 it will be treated as a corefile. If it begins with a digit,
3355 GDB will attempt to attach it as a process, and if no such process
3356 is found, will then attempt to open it as a corefile.
3358 * Changes in ARM configurations.
3360 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3361 configuration is fully multi-arch.
3363 * New native configurations
3365 ARM NetBSD arm*-*-netbsd*
3366 x86 OpenBSD i[3456]86-*-openbsd*
3367 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3368 Sparc64 running FreeBSD sparc64-*-freebsd*
3372 Sanyo XStormy16 xstormy16-elf
3374 * OBSOLETE configurations and files
3376 Configurations that have been declared obsolete in this release have
3377 been commented out. Unless there is activity to revive these
3378 configurations, the next release of GDB will have their sources
3379 permanently REMOVED.
3381 AMD 29k family via UDI a29k-amd-udi, udi29k
3382 A29K VxWorks a29k-*-vxworks
3383 AMD 29000 embedded, using EBMON a29k-none-none
3384 AMD 29000 embedded with COFF a29k-none-coff
3385 AMD 29000 embedded with a.out a29k-none-aout
3387 testsuite/gdb.hp/gdb.threads-hp/ directory
3389 * REMOVED configurations and files
3391 TI TMS320C80 tic80-*-*
3393 PowerPC Solaris powerpcle-*-solaris*
3394 PowerPC Windows NT powerpcle-*-cygwin32
3395 PowerPC Netware powerpc-*-netware*
3396 Harris/CXUX m88k m88*-harris-cxux*
3397 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3398 ns32k-utek-sysv* ns32k-utek-*
3399 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3400 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3401 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3402 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3403 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3405 * Changes to command line processing
3407 The new `--args' feature can be used to specify command-line arguments
3408 for the inferior from gdb's command line.
3410 * Changes to key bindings
3412 There is a new `operate-and-get-next' function bound to `C-o'.
3414 *** Changes in GDB 5.1.1
3416 Fix compile problem on DJGPP.
3418 Fix a problem with floating-point registers on the i386 being
3421 Fix to stop GDB crashing on .debug_str debug info.
3423 Numerous documentation fixes.
3425 Numerous testsuite fixes.
3427 *** Changes in GDB 5.1:
3429 * New native configurations
3431 Alpha FreeBSD alpha*-*-freebsd*
3432 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3433 MIPS GNU/Linux mips*-*-linux*
3434 MIPS SGI Irix 6.x mips*-sgi-irix6*
3435 ia64 AIX ia64-*-aix*
3436 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3440 Motorola 68HC11 and 68HC12 m68hc11-elf
3442 UltraSparc running GNU/Linux sparc64-*-linux*
3444 * OBSOLETE configurations and files
3446 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3447 Harris/CXUX m88k m88*-harris-cxux*
3448 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3449 ns32k-utek-sysv* ns32k-utek-*
3450 TI TMS320C80 tic80-*-*
3452 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3453 PowerPC Solaris powerpcle-*-solaris*
3454 PowerPC Windows NT powerpcle-*-cygwin32
3455 PowerPC Netware powerpc-*-netware*
3456 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3457 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3458 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3459 Apple Macintosh (MPW) host N/A
3461 stuff.c (Program to stuff files into a specially prepared space in kdb)
3462 kdb-start.c (Main loop for the standalone kernel debugger)
3464 Configurations that have been declared obsolete in this release have
3465 been commented out. Unless there is activity to revive these
3466 configurations, the next release of GDB will have their sources
3467 permanently REMOVED.
3469 * REMOVED configurations and files
3471 Altos 3068 m68*-altos-*
3472 Convex c1-*-*, c2-*-*
3474 ARM RISCix arm-*-* (as host)
3478 * GDB has been converted to ISO C.
3480 GDB's source code has been converted to ISO C. In particular, the
3481 sources are fully protoized, and rely on standard headers being
3486 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3488 * The MI enabled by default.
3490 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3491 revised and enabled by default. Packages which use GDB as a debugging
3492 engine behind a UI or another front end are encouraged to switch to
3493 using the GDB/MI interface, instead of the old annotations interface
3494 which is now deprecated.
3496 * Support for debugging Pascal programs.
3498 GDB now includes support for debugging Pascal programs. The following
3499 main features are supported:
3501 - Pascal-specific data types such as sets;
3503 - automatic recognition of Pascal sources based on file-name
3506 - Pascal-style display of data types, variables, and functions;
3508 - a Pascal expression parser.
3510 However, some important features are not yet supported.
3512 - Pascal string operations are not supported at all;
3514 - there are some problems with boolean types;
3516 - Pascal type hexadecimal constants are not supported
3517 because they conflict with the internal variables format;
3519 - support for Pascal objects and classes is not full yet;
3521 - unlike Pascal, GDB is case-sensitive for symbol names.
3523 * Changes in completion.
3525 Commands such as `shell', `run' and `set args', which pass arguments
3526 to inferior programs, now complete on file names, similar to what
3527 users expect at the shell prompt.
3529 Commands which accept locations, such as `disassemble', `print',
3530 `breakpoint', `until', etc. now complete on filenames as well as
3531 program symbols. Thus, if you type "break foob TAB", and the source
3532 files linked into the programs include `foobar.c', that file name will
3533 be one of the candidates for completion. However, file names are not
3534 considered for completion after you typed a colon that delimits a file
3535 name from a name of a function in that file, as in "break foo.c:bar".
3537 `set demangle-style' completes on available demangling styles.
3539 * New platform-independent commands:
3541 It is now possible to define a post-hook for a command as well as a
3542 hook that runs before the command. For more details, see the
3543 documentation of `hookpost' in the GDB manual.
3545 * Changes in GNU/Linux native debugging.
3547 Support for debugging multi-threaded programs has been completely
3548 revised for all platforms except m68k and sparc. You can now debug as
3549 many threads as your system allows you to have.
3551 Attach/detach is supported for multi-threaded programs.
3553 Support for SSE registers was added for x86. This doesn't work for
3554 multi-threaded programs though.
3556 * Changes in MIPS configurations.
3558 Multi-arch support is enabled for all MIPS configurations.
3560 GDB can now be built as native debugger on SGI Irix 6.x systems for
3561 debugging n32 executables. (Debugging 64-bit executables is not yet
3564 * Unified support for hardware watchpoints in all x86 configurations.
3566 Most (if not all) native x86 configurations support hardware-assisted
3567 breakpoints and watchpoints in a unified manner. This support
3568 implements debug register sharing between watchpoints, which allows to
3569 put a virtually infinite number of watchpoints on the same address,
3570 and also supports watching regions up to 16 bytes with several debug
3573 The new maintenance command `maintenance show-debug-regs' toggles
3574 debugging print-outs in functions that insert, remove, and test
3575 watchpoints and hardware breakpoints.
3577 * Changes in the DJGPP native configuration.
3579 New command ``info dos sysinfo'' displays assorted information about
3580 the CPU, OS, memory, and DPMI server.
3582 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3583 display information about segment descriptors stored in GDT, LDT, and
3586 New commands ``info dos pde'' and ``info dos pte'' display entries
3587 from Page Directory and Page Tables (for now works with CWSDPMI only).
3588 New command ``info dos address-pte'' displays the Page Table entry for
3589 a given linear address.
3591 GDB can now pass command lines longer than 126 characters to the
3592 program being debugged (requires an update to the libdbg.a library
3593 which is part of the DJGPP development kit).
3595 DWARF2 debug info is now supported.
3597 It is now possible to `step' and `next' through calls to `longjmp'.
3599 * Changes in documentation.
3601 All GDB documentation was converted to GFDL, the GNU Free
3602 Documentation License.
3604 Tracepoints-related commands are now fully documented in the GDB
3607 TUI, the Text-mode User Interface, is now documented in the manual.
3609 Tracepoints-related commands are now fully documented in the GDB
3612 The "GDB Internals" manual now has an index. It also includes
3613 documentation of `ui_out' functions, GDB coding standards, x86
3614 hardware watchpoints, and memory region attributes.
3616 * GDB's version number moved to ``version.in''
3618 The Makefile variable VERSION has been replaced by the file
3619 ``version.in''. People creating GDB distributions should update the
3620 contents of this file.
3624 GUD support is now a standard part of the EMACS distribution.
3626 *** Changes in GDB 5.0:
3628 * Improved support for debugging FP programs on x86 targets
3630 Unified and much-improved support for debugging floating-point
3631 programs on all x86 targets. In particular, ``info float'' now
3632 displays the FP registers in the same format on all x86 targets, with
3633 greater level of detail.
3635 * Improvements and bugfixes in hardware-assisted watchpoints
3637 It is now possible to watch array elements, struct members, and
3638 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3639 on x86 targets no longer erroneously trigger when the address is
3642 * Improvements in the native DJGPP version of GDB
3644 The distribution now includes all the scripts and auxiliary files
3645 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3646 machines ``out of the box''.
3648 The DJGPP version can now debug programs that use signals. It is
3649 possible to catch signals that happened in the debuggee, deliver
3650 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3651 would kill the program being debugged.) Programs that hook hardware
3652 interrupts (keyboard, timer, etc.) can also be debugged.
3654 It is now possible to debug DJGPP programs that redirect their
3655 standard handles or switch them to raw (as opposed to cooked) mode, or
3656 even close them. The command ``run < foo > bar'' works as expected,
3657 and ``info terminal'' reports useful information about the debuggee's
3658 terminal, including raw/cooked mode, redirection, etc.
3660 The DJGPP version now uses termios functions for console I/O, which
3661 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3664 DOS-style file names with drive letters are now fully supported by
3667 It is now possible to debug DJGPP programs that switch their working
3668 directory. It is also possible to rerun the debuggee any number of
3669 times without restarting GDB; thus, you can use the same setup,
3670 breakpoints, etc. for many debugging sessions.
3672 * New native configurations
3674 ARM GNU/Linux arm*-*-linux*
3675 PowerPC GNU/Linux powerpc-*-linux*
3679 Motorola MCore mcore-*-*
3680 x86 VxWorks i[3456]86-*-vxworks*
3681 PowerPC VxWorks powerpc-*-vxworks*
3682 TI TMS320C80 tic80-*-*
3684 * OBSOLETE configurations
3686 Altos 3068 m68*-altos-*
3687 Convex c1-*-*, c2-*-*
3689 ARM RISCix arm-*-* (as host)
3692 Configurations that have been declared obsolete will be commented out,
3693 but the code will be left in place. If there is no activity to revive
3694 these configurations before the next release of GDB, the sources will
3695 be permanently REMOVED.
3697 * Gould support removed
3699 Support for the Gould PowerNode and NP1 has been removed.
3701 * New features for SVR4
3703 On SVR4 native platforms (such as Solaris), if you attach to a process
3704 without first loading a symbol file, GDB will now attempt to locate and
3705 load symbols from the running process's executable file.
3707 * Many C++ enhancements
3709 C++ support has been greatly improved. Overload resolution now works properly
3710 in almost all cases. RTTI support is on the way.
3712 * Remote targets can connect to a sub-program
3714 A popen(3) style serial-device has been added. This device starts a
3715 sub-process (such as a stand-alone simulator) and then communicates
3716 with that. The sub-program to run is specified using the syntax
3717 ``|<program> <args>'' vis:
3719 (gdb) set remotedebug 1
3720 (gdb) target extended-remote |mn10300-elf-sim program-args
3722 * MIPS 64 remote protocol
3724 A long standing bug in the mips64 remote protocol where by GDB
3725 expected certain 32 bit registers (ex SR) to be transfered as 32
3726 instead of 64 bits has been fixed.
3728 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3729 added to provide backward compatibility with older versions of GDB.
3731 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3733 The command ``set remotebinarydownload'' command has been replaced by
3734 ``set remote X-packet''. Other commands in ``set remote'' family
3735 include ``set remote P-packet''.
3737 * Breakpoint commands accept ranges.
3739 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3740 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3741 ``tracepoint passcount'' also accepts a range of tracepoints.
3743 * ``apropos'' command added.
3745 The ``apropos'' command searches through command names and
3746 documentation strings, printing out matches, making it much easier to
3747 try to find a command that does what you are looking for.
3751 A new machine oriented interface (MI) has been added to GDB. This
3752 interface is designed for debug environments running GDB as a separate
3753 process. This is part of the long term libGDB project. See the
3754 "GDB/MI" chapter of the GDB manual for further information. It can be
3755 enabled by configuring with:
3757 .../configure --enable-gdbmi
3759 *** Changes in GDB-4.18:
3761 * New native configurations
3763 HP-UX 10.20 hppa*-*-hpux10.20
3764 HP-UX 11.x hppa*-*-hpux11.0*
3765 M68K GNU/Linux m68*-*-linux*
3769 Fujitsu FR30 fr30-*-elf*
3770 Intel StrongARM strongarm-*-*
3771 Mitsubishi D30V d30v-*-*
3773 * OBSOLETE configurations
3775 Gould PowerNode, NP1 np1-*-*, pn-*-*
3777 Configurations that have been declared obsolete will be commented out,
3778 but the code will be left in place. If there is no activity to revive
3779 these configurations before the next release of GDB, the sources will
3780 be permanently REMOVED.
3784 As a compatibility experiment, GDB's source files buildsym.h and
3785 buildsym.c have been converted to pure standard C, no longer
3786 containing any K&R compatibility code. We believe that all systems in
3787 use today either come with a standard C compiler, or have a GCC port
3788 available. If this is not true, please report the affected
3789 configuration to bug-gdb@gnu.org immediately. See the README file for
3790 information about getting a standard C compiler if you don't have one
3795 GDB now uses readline 2.2.
3797 * set extension-language
3799 You can now control the mapping between filename extensions and source
3800 languages by using the `set extension-language' command. For instance,
3801 you can ask GDB to treat .c files as C++ by saying
3802 set extension-language .c c++
3803 The command `info extensions' lists all of the recognized extensions
3804 and their associated languages.
3806 * Setting processor type for PowerPC and RS/6000
3808 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3809 you can use the `set processor' command to specify what variant of the
3810 PowerPC family you are debugging. The command
3814 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3815 following PowerPC and RS6000 variants:
3817 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3818 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3820 403GC IBM PowerPC 403GC
3821 505 Motorola PowerPC 505
3822 860 Motorola PowerPC 860 or 850
3823 601 Motorola PowerPC 601
3824 602 Motorola PowerPC 602
3825 603 Motorola/IBM PowerPC 603 or 603e
3826 604 Motorola PowerPC 604 or 604e
3827 750 Motorola/IBM PowerPC 750 or 750
3829 At the moment, this command just tells GDB what to name the
3830 special-purpose processor registers. Since almost all the affected
3831 registers are inaccessible to user-level programs, this command is
3832 only useful for remote debugging in its present form.
3836 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3837 more extensive support for HP-UX. Added features include shared
3838 library support, kernel threads and hardware watchpoints for 11.00,
3839 support for HP's ANSI C and C++ compilers, and a compatibility mode
3840 for xdb and dbx commands.
3844 HP's donation includes the new concept of catchpoints, which is a
3845 generalization of the old catch command. On HP-UX, it is now possible
3846 to catch exec, fork, and vfork, as well as library loading.
3848 This means that the existing catch command has changed; its first
3849 argument now specifies the type of catch to be set up. See the
3850 output of "help catch" for a list of catchpoint types.
3852 * Debugging across forks
3854 On HP-UX, you can choose which process to debug when a fork() happens
3859 HP has donated a curses-based terminal user interface (TUI). To get
3860 it, build with --enable-tui. Although this can be enabled for any
3861 configuration, at present it only works for native HP debugging.
3863 * GDB remote protocol additions
3865 A new protocol packet 'X' that writes binary data is now available.
3866 Default behavior is to try 'X', then drop back to 'M' if the stub
3867 fails to respond. The settable variable `remotebinarydownload'
3868 allows explicit control over the use of 'X'.
3870 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3871 full 64-bit address. The command
3873 set remoteaddresssize 32
3875 can be used to revert to the old behaviour. For existing remote stubs
3876 the change should not be noticed, as the additional address information
3879 In order to assist in debugging stubs, you may use the maintenance
3880 command `packet' to send any text string to the stub. For instance,
3882 maint packet heythere
3884 sends the packet "$heythere#<checksum>". Note that it is very easy to
3885 disrupt a debugging session by sending the wrong packet at the wrong
3888 The compare-sections command allows you to compare section data on the
3889 target to what is in the executable file without uploading or
3890 downloading, by comparing CRC checksums.
3892 * Tracing can collect general expressions
3894 You may now collect general expressions at tracepoints. This requires
3895 further additions to the target-side stub; see tracepoint.c and
3896 doc/agentexpr.texi for further details.
3898 * mask-address variable for Mips
3900 For Mips targets, you may control the zeroing of the upper 32 bits of
3901 a 64-bit address by entering `set mask-address on'. This is mainly
3902 of interest to users of embedded R4xxx and R5xxx processors.
3904 * Higher serial baud rates
3906 GDB's serial code now allows you to specify baud rates 57600, 115200,
3907 230400, and 460800 baud. (Note that your host system may not be able
3908 to achieve all of these rates.)
3912 The i960 configuration now includes an initial implementation of a
3913 builtin simulator, contributed by Jim Wilson.
3916 *** Changes in GDB-4.17:
3918 * New native configurations
3920 Alpha GNU/Linux alpha*-*-linux*
3921 Unixware 2.x i[3456]86-unixware2*
3922 Irix 6.x mips*-sgi-irix6*
3923 PowerPC GNU/Linux powerpc-*-linux*
3924 PowerPC Solaris powerpcle-*-solaris*
3925 Sparc GNU/Linux sparc-*-linux*
3926 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3930 Argonaut Risc Chip (ARC) arc-*-*
3931 Hitachi H8/300S h8300*-*-*
3932 Matsushita MN10200 w/simulator mn10200-*-*
3933 Matsushita MN10300 w/simulator mn10300-*-*
3934 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3935 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3936 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3937 Mitsubishi D10V w/simulator d10v-*-*
3938 Mitsubishi M32R/D w/simulator m32r-*-elf*
3939 Tsqware Sparclet sparclet-*-*
3940 NEC V850 w/simulator v850-*-*
3942 * New debugging protocols
3944 ARM with RDI protocol arm*-*-*
3945 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3946 DDB and LSI variants of PMON protocol mips*-*-*
3947 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3948 PowerPC with SDS protocol powerpc{,le}-*-eabi
3949 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3953 All configurations can now understand and use the DWARF 2 debugging
3954 format. The choice is automatic, if the symbol file contains DWARF 2
3959 GDB now includes basic Java language support. This support is
3960 only useful with Java compilers that produce native machine code.
3962 * solib-absolute-prefix and solib-search-path
3964 For SunOS and SVR4 shared libraries, you may now set the prefix for
3965 loading absolute shared library symbol files, and the search path for
3966 locating non-absolute shared library symbol files.
3968 * Live range splitting
3970 GDB can now effectively debug code for which GCC has performed live
3971 range splitting as part of its optimization. See gdb/doc/LRS for
3972 more details on the expected format of the stabs information.
3976 GDB's support for the GNU Hurd, including thread debugging, has been
3977 updated to work with current versions of the Hurd.
3981 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3982 instruction set. ARM GDB automatically detects when Thumb
3983 instructions are in use, and adjusts disassembly and backtracing
3988 GDB's MIPS target configurations now handle the MIP16 16-bit
3993 GDB now includes support for overlays; if an executable has been
3994 linked such that multiple sections are based at the same address, GDB
3995 will decide which section to use for symbolic info. You can choose to
3996 control the decision manually, using overlay commands, or implement
3997 additional target-side support and use "overlay load-target" to bring
3998 in the overlay mapping. Do "help overlay" for more detail.
4002 The command "info symbol <address>" displays information about
4003 the symbol at the specified address.
4007 The standard remote protocol now includes an extension that allows
4008 asynchronous collection and display of trace data. This requires
4009 extensive support in the target-side debugging stub. Tracing mode
4010 includes a new interaction mode in GDB and new commands: see the
4011 file tracepoint.c for more details.
4015 Configurations for embedded MIPS now include a simulator contributed
4016 by Cygnus Solutions. The simulator supports the instruction sets
4017 of most MIPS variants.
4021 Sparc configurations may now include the ERC32 simulator contributed
4022 by the European Space Agency. The simulator is not built into
4023 Sparc targets by default; configure with --enable-sim to include it.
4027 For target configurations that may include multiple variants of a
4028 basic architecture (such as MIPS and SH), you may now set the
4029 architecture explicitly. "set arch" sets, "info arch" lists
4030 the possible architectures.
4032 *** Changes in GDB-4.16:
4034 * New native configurations
4036 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4037 M68K NetBSD m68k-*-netbsd*
4038 PowerPC AIX 4.x powerpc-*-aix*
4039 PowerPC MacOS powerpc-*-macos*
4040 PowerPC Windows NT powerpcle-*-cygwin32
4041 RS/6000 AIX 4.x rs6000-*-aix4*
4045 ARM with RDP protocol arm-*-*
4046 I960 with MON960 i960-*-coff
4047 MIPS VxWorks mips*-*-vxworks*
4048 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4049 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4051 Matra Sparclet sparclet-*-*
4055 The powerpc-eabi configuration now includes the PSIM simulator,
4056 contributed by Andrew Cagney, with assistance from Mike Meissner.
4057 PSIM is a very elaborate model of the PowerPC, including not only
4058 basic instruction set execution, but also details of execution unit
4059 performance and I/O hardware. See sim/ppc/README for more details.
4063 GDB now works with Solaris 2.5.
4065 * Windows 95/NT native
4067 GDB will now work as a native debugger on Windows 95 and Windows NT.
4068 To build it from source, you must use the "gnu-win32" environment,
4069 which uses a DLL to emulate enough of Unix to run the GNU tools.
4070 Further information, binaries, and sources are available at
4071 ftp.cygnus.com, under pub/gnu-win32.
4073 * dont-repeat command
4075 If a user-defined command includes the command `dont-repeat', then the
4076 command will not be repeated if the user just types return. This is
4077 useful if the command is time-consuming to run, so that accidental
4078 extra keystrokes don't run the same command many times.
4080 * Send break instead of ^C
4082 The standard remote protocol now includes an option to send a break
4083 rather than a ^C to the target in order to interrupt it. By default,
4084 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4086 * Remote protocol timeout
4088 The standard remote protocol includes a new variable `remotetimeout'
4089 that allows you to set the number of seconds before GDB gives up trying
4090 to read from the target. The default value is 2.
4092 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4094 By default GDB will automatically keep track of objects as they are
4095 loaded and unloaded by the dynamic linker. By using the command `set
4096 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4097 when shared library events occur, thus allowing you to set breakpoints
4098 in shared libraries which are explicitly loaded by the inferior.
4100 Note this feature does not work on hpux8. On hpux9 you must link
4101 /usr/lib/end.o into your program. This feature should work
4102 automatically on hpux10.
4104 * Irix 5.x hardware watchpoint support
4106 Irix 5 configurations now support the use of hardware watchpoints.
4108 * Mips protocol "SYN garbage limit"
4110 When debugging a Mips target using the `target mips' protocol, you
4111 may set the number of characters that GDB will ignore by setting
4112 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4113 every character. The default value is 1050.
4115 * Recording and replaying remote debug sessions
4117 If you set `remotelogfile' to the name of a file, gdb will write to it
4118 a recording of a remote debug session. This recording may then be
4119 replayed back to gdb using "gdbreplay". See gdbserver/README for
4120 details. This is useful when you have a problem with GDB while doing
4121 remote debugging; you can make a recording of the session and send it
4122 to someone else, who can then recreate the problem.
4124 * Speedups for remote debugging
4126 GDB includes speedups for downloading and stepping MIPS systems using
4127 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4128 and more efficient S-record downloading.
4130 * Memory use reductions and statistics collection
4132 GDB now uses less memory and reports statistics about memory usage.
4133 Try the `maint print statistics' command, for example.
4135 *** Changes in GDB-4.15:
4137 * Psymtabs for XCOFF
4139 The symbol reader for AIX GDB now uses partial symbol tables. This
4140 can greatly improve startup time, especially for large executables.
4142 * Remote targets use caching
4144 Remote targets now use a data cache to speed up communication with the
4145 remote side. The data cache could lead to incorrect results because
4146 it doesn't know about volatile variables, thus making it impossible to
4147 debug targets which use memory mapped I/O devices. `set remotecache
4148 off' turns the the data cache off.
4150 * Remote targets may have threads
4152 The standard remote protocol now includes support for multiple threads
4153 in the target system, using new protocol commands 'H' and 'T'. See
4154 gdb/remote.c for details.
4158 If GDB is configured with `--enable-netrom', then it will include
4159 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4160 acts as though it is a bank of ROM on the target board, but you can
4161 write into it over the network. GDB's support consists only of
4162 support for fast loading into the emulated ROM; to debug, you must use
4163 another protocol, such as standard remote protocol. The usual
4164 sequence is something like
4166 target nrom <netrom-hostname>
4168 target remote <netrom-hostname>:1235
4172 GDB now includes support for the Apple Macintosh, as a host only. It
4173 may be run as either an MPW tool or as a standalone application, and
4174 it can debug through the serial port. All the usual GDB commands are
4175 available, but to the target command, you must supply "serial" as the
4176 device type instead of "/dev/ttyXX". See mpw-README in the main
4177 directory for more information on how to build. The MPW configuration
4178 scripts */mpw-config.in support only a few targets, and only the
4179 mips-idt-ecoff target has been tested.
4183 GDB configuration now uses autoconf. This is not user-visible,
4184 but does simplify configuration and building.
4188 GDB now supports hpux10.
4190 *** Changes in GDB-4.14:
4192 * New native configurations
4194 x86 FreeBSD i[345]86-*-freebsd
4195 x86 NetBSD i[345]86-*-netbsd
4196 NS32k NetBSD ns32k-*-netbsd
4197 Sparc NetBSD sparc-*-netbsd
4201 A29K VxWorks a29k-*-vxworks
4202 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4203 CPU32 EST-300 emulator m68*-*-est*
4204 PowerPC ELF powerpc-*-elf
4207 * Alpha OSF/1 support for procfs
4209 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4210 possible to attach to running processes. As the mounting of the /proc
4211 filesystem is optional on the Alpha, GDB automatically determines
4212 the availability of /proc during startup. This can lead to problems
4213 if /proc is unmounted after GDB has been started.
4215 * Arguments to user-defined commands
4217 User commands may accept up to 10 arguments separated by whitespace.
4218 Arguments are accessed within the user command via $arg0..$arg9. A
4221 print $arg0 + $arg1 + $arg2
4223 To execute the command use:
4226 Defines the command "adder" which prints the sum of its three arguments.
4227 Note the arguments are text substitutions, so they may reference variables,
4228 use complex expressions, or even perform inferior function calls.
4230 * New `if' and `while' commands
4232 This makes it possible to write more sophisticated user-defined
4233 commands. Both commands take a single argument, which is the
4234 expression to evaluate, and must be followed by the commands to
4235 execute, one per line, if the expression is nonzero, the list being
4236 terminated by the word `end'. The `if' command list may include an
4237 `else' word, which causes the following commands to be executed only
4238 if the expression is zero.
4240 * Fortran source language mode
4242 GDB now includes partial support for Fortran 77. It will recognize
4243 Fortran programs and can evaluate a subset of Fortran expressions, but
4244 variables and functions may not be handled correctly. GDB will work
4245 with G77, but does not yet know much about symbols emitted by other
4248 * Better HPUX support
4250 Most debugging facilities now work on dynamic executables for HPPAs
4251 running hpux9 or later. You can attach to running dynamically linked
4252 processes, but by default the dynamic libraries will be read-only, so
4253 for instance you won't be able to put breakpoints in them. To change
4254 that behavior do the following before running the program:
4260 This will cause the libraries to be mapped private and read-write.
4261 To revert to the normal behavior, do this:
4267 You cannot set breakpoints or examine data in the library until after
4268 the library is loaded if the function/data symbols do not have
4271 GDB can now also read debug symbols produced by the HP C compiler on
4272 HPPAs (sorry, no C++, Fortran or 68k support).
4274 * Target byte order now dynamically selectable
4276 You can choose which byte order to use with a target system, via the
4277 commands "set endian big" and "set endian little", and you can see the
4278 current setting by using "show endian". You can also give the command
4279 "set endian auto", in which case GDB will use the byte order
4280 associated with the executable. Currently, only embedded MIPS
4281 configurations support dynamic selection of target byte order.
4283 * New DOS host serial code
4285 This version uses DPMI interrupts to handle buffered I/O, so you
4286 no longer need to run asynctsr when debugging boards connected to
4289 *** Changes in GDB-4.13:
4291 * New "complete" command
4293 This lists all the possible completions for the rest of the line, if it
4294 were to be given as a command itself. This is intended for use by emacs.
4296 * Trailing space optional in prompt
4298 "set prompt" no longer adds a space for you after the prompt you set. This
4299 allows you to set a prompt which ends in a space or one that does not.
4301 * Breakpoint hit counts
4303 "info break" now displays a count of the number of times the breakpoint
4304 has been hit. This is especially useful in conjunction with "ignore"; you
4305 can ignore a large number of breakpoint hits, look at the breakpoint info
4306 to see how many times the breakpoint was hit, then run again, ignoring one
4307 less than that number, and this will get you quickly to the last hit of
4310 * Ability to stop printing at NULL character
4312 "set print null-stop" will cause GDB to stop printing the characters of
4313 an array when the first NULL is encountered. This is useful when large
4314 arrays actually contain only short strings.
4316 * Shared library breakpoints
4318 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4319 breakpoints in shared libraries before the executable is run.
4321 * Hardware watchpoints
4323 There is a new hardware breakpoint for the watch command for sparclite
4324 targets. See gdb/sparclite/hw_breakpoint.note.
4326 Hardware watchpoints are also now supported under GNU/Linux.
4330 Annotations have been added. These are for use with graphical interfaces,
4331 and are still experimental. Currently only gdba.el uses these.
4333 * Improved Irix 5 support
4335 GDB now works properly with Irix 5.2.
4337 * Improved HPPA support
4339 GDB now works properly with the latest GCC and GAS.
4341 * New native configurations
4343 Sequent PTX4 i[34]86-sequent-ptx4
4344 HPPA running OSF/1 hppa*-*-osf*
4345 Atari TT running SVR4 m68*-*-sysv4*
4346 RS/6000 LynxOS rs6000-*-lynxos*
4350 OS/9000 i[34]86-*-os9k
4351 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4354 * Hitachi SH7000 and E7000-PC ICE support
4356 There is now support for communicating with the Hitachi E7000-PC ICE.
4357 This is available automatically when GDB is configured for the SH.
4361 As usual, a variety of small fixes and improvements, both generic
4362 and configuration-specific. See the ChangeLog for more detail.
4364 *** Changes in GDB-4.12:
4366 * Irix 5 is now supported
4370 GDB-4.12 on the HPPA has a number of changes which make it unable
4371 to debug the output from the currently released versions of GCC and
4372 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4373 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4374 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4377 *** Changes in GDB-4.11:
4379 * User visible changes:
4383 The "set remotedebug" option is now consistent between the mips remote
4384 target, remote targets using the gdb-specific protocol, UDI (AMD's
4385 debug protocol for the 29k) and the 88k bug monitor. It is now an
4386 integer specifying a debug level (normally 0 or 1, but 2 means more
4387 debugging info for the mips target).
4389 * DEC Alpha native support
4391 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4392 debug info, but GDB works fairly well with the DEC compiler and should
4393 work with a future GCC release. See the README file for a few
4394 Alpha-specific notes.
4396 * Preliminary thread implementation
4398 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4400 * LynxOS native and target support for 386
4402 This release has been hosted on LynxOS 2.2, and also can be configured
4403 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4406 * Improvements in C++ mangling/demangling.
4408 This release has much better g++ debugging, specifically in name
4409 mangling/demangling, virtual function calls, print virtual table,
4410 call methods, ...etc.
4412 *** Changes in GDB-4.10:
4414 * User visible changes:
4416 Remote debugging using the GDB-specific (`target remote') protocol now
4417 supports the `load' command. This is only useful if you have some
4418 other way of getting the stub to the target system, and you can put it
4419 somewhere in memory where it won't get clobbered by the download.
4421 Filename completion now works.
4423 When run under emacs mode, the "info line" command now causes the
4424 arrow to point to the line specified. Also, "info line" prints
4425 addresses in symbolic form (as well as hex).
4427 All vxworks based targets now support a user settable option, called
4428 vxworks-timeout. This option represents the number of seconds gdb
4429 should wait for responses to rpc's. You might want to use this if
4430 your vxworks target is, perhaps, a slow software simulator or happens
4431 to be on the far side of a thin network line.
4435 This release contains support for using a DEC alpha as a GDB host for
4436 cross debugging. Native alpha debugging is not supported yet.
4439 *** Changes in GDB-4.9:
4443 This is the first GDB release which is accompanied by a matching testsuite.
4444 The testsuite requires installation of dejagnu, which should be available
4445 via ftp from most sites that carry GNU software.
4449 'Cfront' style demangling has had its name changed to 'ARM' style, to
4450 emphasize that it was written from the specifications in the C++ Annotated
4451 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4452 disclaimers, it still generated too much confusion with users attempting to
4453 use gdb with AT&T cfront.
4457 GDB now uses a standard remote interface to a simulator library.
4458 So far, the library contains simulators for the Zilog Z8001/2, the
4459 Hitachi H8/300, H8/500 and Super-H.
4461 * New targets supported
4463 H8/300 simulator h8300-hitachi-hms or h8300hms
4464 H8/500 simulator h8500-hitachi-hms or h8500hms
4465 SH simulator sh-hitachi-hms or sh
4466 Z8000 simulator z8k-zilog-none or z8ksim
4467 IDT MIPS board over serial line mips-idt-ecoff
4469 Cross-debugging to GO32 targets is supported. It requires a custom
4470 version of the i386-stub.c module which is integrated with the
4471 GO32 memory extender.
4473 * New remote protocols
4475 MIPS remote debugging protocol.
4477 * New source languages supported
4479 This version includes preliminary support for Chill, a Pascal like language
4480 used by telecommunications companies. Chill support is also being integrated
4481 into the GNU compiler, but we don't know when it will be publically available.
4484 *** Changes in GDB-4.8:
4486 * HP Precision Architecture supported
4488 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4489 version of this support was available as a set of patches from the
4490 University of Utah. GDB does not support debugging of programs
4491 compiled with the HP compiler, because HP will not document their file
4492 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4493 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4495 Many problems in the preliminary version have been fixed.
4497 * Faster and better demangling
4499 We have improved template demangling and fixed numerous bugs in the GNU style
4500 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4501 character types (wchar_t) are now supported. Demangling of each symbol is now
4502 only done once, and is cached when the symbol table for a file is read in.
4503 This results in a small increase in memory usage for C programs, a moderate
4504 increase in memory usage for C++ programs, and a fantastic speedup in
4507 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4508 from the specifications in the Annotated Reference Manual, which AT&T's
4509 compiler does not actually implement.
4511 * G++ multiple inheritance compiler problem
4513 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4514 inheritance lattices was reworked to properly discover ambiguities. We
4515 recently found an example which causes this new algorithm to fail in a
4516 very subtle way, producing bad debug information for those classes.
4517 The file 'gcc.patch' (in this directory) can be applied to gcc to
4518 circumvent the problem. A future GCC release will contain a complete
4521 The previous G++ debug info problem (mentioned below for the gdb-4.7
4522 release) is fixed in gcc version 2.3.2.
4524 * Improved configure script
4526 The `configure' script will now attempt to guess your system type if
4527 you don't supply a host system type. The old scheme of supplying a
4528 host system triplet is preferable over using this. All the magic is
4529 done in the new `config.guess' script. Examine it for details.
4531 We have also brought our configure script much more in line with the FSF's
4532 version. It now supports the --with-xxx options. In particular,
4533 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4534 The resulting GDB will not be able to read arbitrary object file formats --
4535 only the format ``expected'' to be used on the configured target system.
4536 We hope to make this the default in a future release.
4538 * Documentation improvements
4540 There's new internal documentation on how to modify GDB, and how to
4541 produce clean changes to the code. We implore people to read it
4542 before submitting changes.
4544 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4545 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4546 `info' files are also provided. To build `info' files from scratch,
4547 you will need the latest `makeinfo' release, which will be available in
4548 a future texinfo-X.Y release.
4550 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4551 We're not sure exactly which versions have this problem, but it has
4552 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4553 or better. If that isn't possible, there is a patch in
4554 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4555 around this problem.
4559 GDB now supports array constants that can be used in expressions typed in by
4560 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4561 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4564 The new directory `gdb/sparclite' contains a program that demonstrates
4565 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4567 * New native hosts supported
4569 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4570 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4572 * New targets supported
4574 AMD 29k family via UDI a29k-amd-udi or udi29k
4576 * New file formats supported
4578 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4579 HPUX core files, and SCO 3.2v2 core files.
4583 Attaching to processes now works again; thanks for the many bug reports.
4585 We have also stomped on a bunch of core dumps caused by
4586 printf_filtered("%s") problems.
4588 We eliminated a copyright problem on the rpc and ptrace header files
4589 for VxWorks, which was discovered at the last minute during the 4.7
4590 release. You should now be able to build a VxWorks GDB.
4592 You can now interrupt gdb while an attached process is running. This
4593 will cause the attached process to stop, and give control back to GDB.
4595 We fixed problems caused by using too many file descriptors
4596 for reading symbols from object files and libraries. This was
4597 especially a problem for programs that used many (~100) shared
4600 The `step' command now only enters a subroutine if there is line number
4601 information for the subroutine. Otherwise it acts like the `next'
4602 command. Previously, `step' would enter subroutines if there was
4603 any debugging information about the routine. This avoids problems
4604 when using `cc -g1' on MIPS machines.
4606 * Internal improvements
4608 GDB's internal interfaces have been improved to make it easier to support
4609 debugging of multiple languages in the future.
4611 GDB now uses a common structure for symbol information internally.
4612 Minimal symbols (derived from linkage symbols in object files), partial
4613 symbols (from a quick scan of debug information), and full symbols
4614 contain a common subset of information, making it easier to write
4615 shared code that handles any of them.
4617 * New command line options
4619 We now accept --silent as an alias for --quiet.
4623 The memory-mapped-malloc library is now licensed under the GNU Library
4624 General Public License.
4626 *** Changes in GDB-4.7:
4628 * Host/native/target split
4630 GDB has had some major internal surgery to untangle the support for
4631 hosts and remote targets. Now, when you configure GDB for a remote
4632 target, it will no longer load in all of the support for debugging
4633 local programs on the host. When fully completed and tested, this will
4634 ensure that arbitrary host/target combinations are possible.
4636 The primary conceptual shift is to separate the non-portable code in
4637 GDB into three categories. Host specific code is required any time GDB
4638 is compiled on that host, regardless of the target. Target specific
4639 code relates to the peculiarities of the target, but can be compiled on
4640 any host. Native specific code is everything else: it can only be
4641 built when the host and target are the same system. Child process
4642 handling and core file support are two common `native' examples.
4644 GDB's use of /proc for controlling Unix child processes is now cleaner.
4645 It has been split out into a single module under the `target_ops' vector,
4646 plus two native-dependent functions for each system that uses /proc.
4648 * New hosts supported
4650 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4651 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4652 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4654 * New targets supported
4656 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4657 68030 and CPU32 m68030-*-*, m68332-*-*
4659 * New native hosts supported
4661 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4662 (386bsd is not well tested yet)
4663 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4665 * New file formats supported
4667 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4668 supports reading of `a.out.adobe' object files, which are an a.out
4669 format extended with minimal information about multiple sections.
4673 `show copying' is the same as the old `info copying'.
4674 `show warranty' is the same as `info warrantee'.
4675 These were renamed for consistency. The old commands continue to work.
4677 `info handle' is a new alias for `info signals'.
4679 You can now define pre-command hooks, which attach arbitrary command
4680 scripts to any command. The commands in the hook will be executed
4681 prior to the user's command. You can also create a hook which will be
4682 executed whenever the program stops. See gdb.texinfo.
4686 We now deal with Cfront style name mangling, and can even extract type
4687 info from mangled symbols. GDB can automatically figure out which
4688 symbol mangling style your C++ compiler uses.
4690 Calling of methods and virtual functions has been improved as well.
4694 The crash that occured when debugging Sun Ansi-C compiled binaries is
4695 fixed. This was due to mishandling of the extra N_SO stabs output
4698 We also finally got Ultrix 4.2 running in house, and fixed core file
4699 support, with help from a dozen people on the net.
4701 John M. Farrell discovered that the reason that single-stepping was so
4702 slow on all of the Mips based platforms (primarily SGI and DEC) was
4703 that we were trying to demangle and lookup a symbol used for internal
4704 purposes on every instruction that was being stepped through. Changing
4705 the name of that symbol so that it couldn't be mistaken for a C++
4706 mangled symbol sped things up a great deal.
4708 Rich Pixley sped up symbol lookups in general by getting much smarter
4709 about when C++ symbol mangling is necessary. This should make symbol
4710 completion (TAB on the command line) much faster. It's not as fast as
4711 we'd like, but it's significantly faster than gdb-4.6.
4715 A new user controllable variable 'call_scratch_address' can
4716 specify the location of a scratch area to be used when GDB
4717 calls a function in the target. This is necessary because the
4718 usual method of putting the scratch area on the stack does not work
4719 in systems that have separate instruction and data spaces.
4721 We integrated changes to support the 29k UDI (Universal Debugger
4722 Interface), but discovered at the last minute that we didn't have all
4723 of the appropriate copyright paperwork. We are working with AMD to
4724 resolve this, and hope to have it available soon.
4728 We have sped up the remote serial line protocol, especially for targets
4729 with lots of registers. It now supports a new `expedited status' ('T')
4730 message which can be used in place of the existing 'S' status message.
4731 This allows the remote stub to send only the registers that GDB
4732 needs to make a quick decision about single-stepping or conditional
4733 breakpoints, eliminating the need to fetch the entire register set for
4734 each instruction being stepped through.
4736 The GDB remote serial protocol now implements a write-through cache for
4737 registers, only re-reading the registers if the target has run.
4739 There is also a new remote serial stub for SPARC processors. You can
4740 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4741 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4742 processor with a serial port.
4746 Configure.in files have become much easier to read and modify. A new
4747 `table driven' format makes it more obvious what configurations are
4748 supported, and what files each one uses.
4752 There is a new opcodes library which will eventually contain all of the
4753 disassembly routines and opcode tables. At present, it only contains
4754 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4755 disassembler (binutils/objdump) to share these routines.
4757 The libiberty library is now copylefted under the GNU Library General
4758 Public License. This allows more liberal use, and was done so libg++
4759 can use it. This makes no difference to GDB, since the Library License
4760 grants all the rights from the General Public License.
4764 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4765 reference to the stabs symbol info used by the debugger. It is (as far
4766 as we know) the only published document on this fascinating topic. We
4767 encourage you to read it, compare it to the stabs information on your
4768 system, and send improvements on the document in general (to
4769 bug-gdb@prep.ai.mit.edu).
4771 And, of course, many bugs have been fixed.
4774 *** Changes in GDB-4.6:
4776 * Better support for C++ function names
4778 GDB now accepts as input the "demangled form" of C++ overloaded function
4779 names and member function names, and can do command completion on such names
4780 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4781 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4782 Make use of command completion, it is your friend.
4784 GDB also now accepts a variety of C++ mangled symbol formats. They are
4785 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4786 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4787 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4788 for the list of formats.
4790 * G++ symbol mangling problem
4792 Recent versions of gcc have a bug in how they emit debugging information for
4793 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4794 directory) can be applied to gcc to fix the problem. Alternatively, if you
4795 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4796 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4797 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4800 * New 'maintenance' command
4802 All of the commands related to hacking GDB internals have been moved out of
4803 the main command set, and now live behind the 'maintenance' command. This
4804 can also be abbreviated as 'mt'. The following changes were made:
4806 dump-me -> maintenance dump-me
4807 info all-breakpoints -> maintenance info breakpoints
4808 printmsyms -> maintenance print msyms
4809 printobjfiles -> maintenance print objfiles
4810 printpsyms -> maintenance print psymbols
4811 printsyms -> maintenance print symbols
4813 The following commands are new:
4815 maintenance demangle Call internal GDB demangler routine to
4816 demangle a C++ link name and prints the result.
4817 maintenance print type Print a type chain for a given symbol
4819 * Change to .gdbinit file processing
4821 We now read the $HOME/.gdbinit file before processing the argv arguments
4822 (e.g. reading symbol files or core files). This allows global parameters to
4823 be set, which will apply during the symbol reading. The ./.gdbinit is still
4824 read after argv processing.
4826 * New hosts supported
4828 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4830 GNU/Linux support i386-unknown-linux or linux
4832 We are also including code to support the HP/PA running BSD and HPUX. This
4833 is almost guaranteed not to work, as we didn't have time to test or build it
4834 for this release. We are including it so that the more adventurous (or
4835 masochistic) of you can play with it. We also had major problems with the
4836 fact that the compiler that we got from HP doesn't support the -g option.
4839 * New targets supported
4841 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4843 * More smarts about finding #include files
4845 GDB now remembers the compilation directory for all include files, and for
4846 all files from which C is generated (like yacc and lex sources). This
4847 greatly improves GDB's ability to find yacc/lex sources, and include files,
4848 especially if you are debugging your program from a directory different from
4849 the one that contains your sources.
4851 We also fixed a bug which caused difficulty with listing and setting
4852 breakpoints in include files which contain C code. (In the past, you had to
4853 try twice in order to list an include file that you hadn't looked at before.)
4855 * Interesting infernals change
4857 GDB now deals with arbitrary numbers of sections, where the symbols for each
4858 section must be relocated relative to that section's landing place in the
4859 target's address space. This work was needed to support ELF with embedded
4860 stabs used by Solaris-2.0.
4862 * Bug fixes (of course!)
4864 There have been loads of fixes for the following things:
4865 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4866 i960, stabs, DOS(GO32), procfs, etc...
4868 See the ChangeLog for details.
4870 *** Changes in GDB-4.5:
4872 * New machines supported (host and target)
4874 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4876 SGI Irix-4.x mips-sgi-irix4 or iris4
4878 * New malloc package
4880 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4881 Mmalloc is capable of handling mutiple heaps of memory. It is also
4882 capable of saving a heap to a file, and then mapping it back in later.
4883 This can be used to greatly speedup the startup of GDB by using a
4884 pre-parsed symbol table which lives in a mmalloc managed heap. For
4885 more details, please read mmalloc/mmalloc.texi.
4889 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4890 'help info proc' for details.
4892 * MIPS ecoff symbol table format
4894 The code that reads MIPS symbol table format is now supported on all hosts.
4895 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4898 * File name changes for MS-DOS
4900 Many files in the config directories have been renamed to make it easier to
4901 support GDB on MS-DOSe systems (which have very restrictive file name
4902 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4903 environment) is close to working but has some remaining problems. Note
4904 that debugging of DOS programs is not supported, due to limitations
4905 in the ``operating system'', but it can be used to host cross-debugging.
4907 * Cross byte order fixes
4909 Many fixes have been made to support cross debugging of Sparc and MIPS
4910 targets from hosts whose byte order differs.
4912 * New -mapped and -readnow options
4914 If memory-mapped files are available on your system through the 'mmap'
4915 system call, you can use the -mapped option on the `file' or
4916 `symbol-file' commands to cause GDB to write the symbols from your
4917 program into a reusable file. If the program you are debugging is
4918 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4919 Future GDB debugging sessions will notice the presence of this file,
4920 and will quickly map in symbol information from it, rather than reading
4921 the symbol table from the executable program. Using the '-mapped'
4922 option in a GDB `file' or `symbol-file' command has the same effect as
4923 starting GDB with the '-mapped' command-line option.
4925 You can cause GDB to read the entire symbol table immediately by using
4926 the '-readnow' option with any of the commands that load symbol table
4927 information (or on the GDB command line). This makes the command
4928 slower, but makes future operations faster.
4930 The -mapped and -readnow options are typically combined in order to
4931 build a `fred.syms' file that contains complete symbol information.
4932 A simple GDB invocation to do nothing but build a `.syms' file for future
4935 gdb -batch -nx -mapped -readnow programname
4937 The `.syms' file is specific to the host machine on which GDB is run.
4938 It holds an exact image of GDB's internal symbol table. It cannot be
4939 shared across multiple host platforms.
4941 * longjmp() handling
4943 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4944 siglongjmp() without losing control. This feature has not yet been ported to
4945 all systems. It currently works on many 386 platforms, all MIPS-based
4946 platforms (SGI, DECstation, etc), and Sun3/4.
4950 Preliminary work has been put in to support the new Solaris OS from Sun. At
4951 this time, it can control and debug processes, but it is not capable of
4956 As always, many many bug fixes. The major areas were with g++, and mipsread.
4957 People using the MIPS-based platforms should experience fewer mysterious
4958 crashes and trashed symbol tables.
4960 *** Changes in GDB-4.4:
4962 * New machines supported (host and target)
4964 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4966 BSD Reno on Vax vax-dec-bsd
4967 Ultrix on Vax vax-dec-ultrix
4969 * New machines supported (target)
4971 AMD 29000 embedded, using EBMON a29k-none-none
4975 GDB continues to improve its handling of C++. `References' work better.
4976 The demangler has also been improved, and now deals with symbols mangled as
4977 per the Annotated C++ Reference Guide.
4979 GDB also now handles `stabs' symbol information embedded in MIPS
4980 `ecoff' symbol tables. Since the ecoff format was not easily
4981 extensible to handle new languages such as C++, this appeared to be a
4982 good way to put C++ debugging info into MIPS binaries. This option
4983 will be supported in the GNU C compiler, version 2, when it is
4986 * New features for SVR4
4988 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4989 shared libraries. Debugging dynamically linked programs should present
4990 only minor differences from debugging statically linked programs.
4992 The `info proc' command will print out information about any process
4993 on an SVR4 system (including the one you are debugging). At the moment,
4994 it prints the address mappings of the process.
4996 If you bring up GDB on another SVR4 system, please send mail to
4997 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4999 * Better dynamic linking support in SunOS
5001 Reading symbols from shared libraries which contain debugging symbols
5002 now works properly. However, there remain issues such as automatic
5003 skipping of `transfer vector' code during function calls, which
5004 make it harder to debug code in a shared library, than to debug the
5005 same code linked statically.
5009 GDB is now using the latest `getopt' routines from the FSF. This
5010 version accepts the -- prefix for options with long names. GDB will
5011 continue to accept the old forms (-option and +option) as well.
5012 Various single letter abbreviations for options have been explicity
5013 added to the option table so that they won't get overshadowed in the
5014 future by other options that begin with the same letter.
5018 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5019 Many assorted bugs have been handled. Many more remain to be handled.
5020 See the various ChangeLog files (primarily in gdb and bfd) for details.
5023 *** Changes in GDB-4.3:
5025 * New machines supported (host and target)
5027 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5028 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5029 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5031 * Almost SCO Unix support
5033 We had hoped to support:
5034 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5035 (except for core file support), but we discovered very late in the release
5036 that it has problems with process groups that render gdb unusable. Sorry
5037 about that. I encourage people to fix it and post the fixes.
5039 * Preliminary ELF and DWARF support
5041 GDB can read ELF object files on System V Release 4, and can handle
5042 debugging records for C, in DWARF format, in ELF files. This support
5043 is preliminary. If you bring up GDB on another SVR4 system, please
5044 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5049 GDB now uses the latest `readline' library. One user-visible change
5050 is that two tabs will list possible command completions, which previously
5051 required typing M-? (meta-question mark, or ESC ?).
5055 The `stepi' bug that many of you noticed has been squashed.
5056 Many bugs in C++ have been handled. Many more remain to be handled.
5057 See the various ChangeLog files (primarily in gdb and bfd) for details.
5059 * State of the MIPS world (in case you wondered):
5061 GDB can understand the symbol tables emitted by the compilers
5062 supplied by most vendors of MIPS-based machines, including DEC. These
5063 symbol tables are in a format that essentially nobody else uses.
5065 Some versions of gcc come with an assembler post-processor called
5066 mips-tfile. This program is required if you want to do source-level
5067 debugging of gcc-compiled programs. I believe FSF does not ship
5068 mips-tfile with gcc version 1, but it will eventually come with gcc
5071 Debugging of g++ output remains a problem. g++ version 1.xx does not
5072 really support it at all. (If you're lucky, you should be able to get
5073 line numbers and stack traces to work, but no parameters or local
5074 variables.) With some work it should be possible to improve the
5077 When gcc version 2 is released, you will have somewhat better luck.
5078 However, even then you will get confusing results for inheritance and
5081 We will eventually provide full debugging of g++ output on
5082 DECstations. This will probably involve some kind of stabs-in-ecoff
5083 encapulation, but the details have not been worked out yet.
5086 *** Changes in GDB-4.2:
5088 * Improved configuration
5090 Only one copy of `configure' exists now, and it is not self-modifying.
5091 Porting BFD is simpler.
5095 The `step' and `next' commands now only stop at the first instruction
5096 of a source line. This prevents the multiple stops that used to occur
5097 in switch statements, for-loops, etc. `Step' continues to stop if a
5098 function that has debugging information is called within the line.
5102 Lots of small bugs fixed. More remain.
5104 * New host supported (not target)
5106 Intel 386 PC clone running Mach i386-none-mach
5109 *** Changes in GDB-4.1:
5111 * Multiple source language support
5113 GDB now has internal scaffolding to handle several source languages.
5114 It determines the type of each source file from its filename extension,
5115 and will switch expression parsing and number formatting to match the
5116 language of the function in the currently selected stack frame.
5117 You can also specifically set the language to be used, with
5118 `set language c' or `set language modula-2'.
5122 GDB now has preliminary support for the GNU Modula-2 compiler,
5123 currently under development at the State University of New York at
5124 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5125 continue through the fall of 1991 and into 1992.
5127 Other Modula-2 compilers are currently not supported, and attempting to
5128 debug programs compiled with them will likely result in an error as the
5129 symbol table is read. Feel free to work on it, though!
5131 There are hooks in GDB for strict type checking and range checking,
5132 in the `Modula-2 philosophy', but they do not currently work.
5136 GDB can now write to executable and core files (e.g. patch
5137 a variable's value). You must turn this switch on, specify
5138 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5139 by assigning a new value to a variable. Modifications take
5142 * Automatic SunOS shared library reading
5144 When you run your program, GDB automatically determines where its
5145 shared libraries (if any) have been loaded, and reads their symbols.
5146 The `share' command is no longer needed. This also works when
5147 examining core files.
5151 You can specify the number of lines that the `list' command shows.
5154 * New machines supported (host and target)
5156 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5157 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5158 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5160 * New hosts supported (not targets)
5162 IBM RT/PC: romp-ibm-aix or rtpc
5164 * New targets supported (not hosts)
5166 AMD 29000 embedded with COFF a29k-none-coff
5167 AMD 29000 embedded with a.out a29k-none-aout
5168 Ultracomputer remote kernel debug a29k-nyu-kern
5170 * New remote interfaces
5176 *** Changes in GDB-4.0:
5180 Wide output is wrapped at good places to make the output more readable.
5182 Gdb now supports cross-debugging from a host machine of one type to a
5183 target machine of another type. Communication with the target system
5184 is over serial lines. The ``target'' command handles connecting to the
5185 remote system; the ``load'' command will download a program into the
5186 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5187 also supports debugging of realtime processes running under VxWorks,
5188 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5189 stub on the target system.
5191 New CPUs supported include the AMD 29000 and Intel 960.
5193 GDB now reads object files and symbol tables via a ``binary file''
5194 library, which allows a single copy of GDB to debug programs of multiple
5195 object file types such as a.out and coff.
5197 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5198 refcard.dvi and refcard.ps are available to format it).
5201 * Control-Variable user interface simplified
5203 All variables that control the operation of the debugger can be set
5204 by the ``set'' command, and displayed by the ``show'' command.
5206 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5207 ``Show prompt'' produces the response:
5208 Gdb's prompt is new-gdb=>.
5210 What follows are the NEW set commands. The command ``help set'' will
5211 print a complete list of old and new set commands. ``help set FOO''
5212 will give a longer description of the variable FOO. ``show'' will show
5213 all of the variable descriptions and their current settings.
5215 confirm on/off: Enables warning questions for operations that are
5216 hard to recover from, e.g. rerunning the program while
5217 it is already running. Default is ON.
5219 editing on/off: Enables EMACS style command line editing
5220 of input. Previous lines can be recalled with
5221 control-P, the current line can be edited with control-B,
5222 you can search for commands with control-R, etc.
5225 history filename NAME: NAME is where the gdb command history
5226 will be stored. The default is .gdb_history,
5227 or the value of the environment variable
5230 history size N: The size, in commands, of the command history. The
5231 default is 256, or the value of the environment variable
5234 history save on/off: If this value is set to ON, the history file will
5235 be saved after exiting gdb. If set to OFF, the
5236 file will not be saved. The default is OFF.
5238 history expansion on/off: If this value is set to ON, then csh-like
5239 history expansion will be performed on
5240 command line input. The default is OFF.
5242 radix N: Sets the default radix for input and output. It can be set
5243 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5244 in the current radix, so "set radix 10" is always a no-op.
5246 height N: This integer value is the number of lines on a page. Default
5247 is 24, the current `stty rows'' setting, or the ``li#''
5248 setting from the termcap entry matching the environment
5251 width N: This integer value is the number of characters on a line.
5252 Default is 80, the current `stty cols'' setting, or the ``co#''
5253 setting from the termcap entry matching the environment
5256 Note: ``set screensize'' is obsolete. Use ``set height'' and
5257 ``set width'' instead.
5259 print address on/off: Print memory addresses in various command displays,
5260 such as stack traces and structure values. Gdb looks
5261 more ``symbolic'' if you turn this off; it looks more
5262 ``machine level'' with it on. Default is ON.
5264 print array on/off: Prettyprint arrays. New convenient format! Default
5267 print demangle on/off: Print C++ symbols in "source" form if on,
5270 print asm-demangle on/off: Same, for assembler level printouts
5273 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5276 * Support for Epoch Environment.
5278 The epoch environment is a version of Emacs v18 with windowing. One
5279 new command, ``inspect'', is identical to ``print'', except that if you
5280 are running in the epoch environment, the value is printed in its own
5284 * Support for Shared Libraries
5286 GDB can now debug programs and core files that use SunOS shared libraries.
5287 Symbols from a shared library cannot be referenced
5288 before the shared library has been linked with the program (this
5289 happens after you type ``run'' and before the function main() is entered).
5290 At any time after this linking (including when examining core files
5291 from dynamically linked programs), gdb reads the symbols from each
5292 shared library when you type the ``sharedlibrary'' command.
5293 It can be abbreviated ``share''.
5295 sharedlibrary REGEXP: Load shared object library symbols for files
5296 matching a unix regular expression. No argument
5297 indicates to load symbols for all shared libraries.
5299 info sharedlibrary: Status of loaded shared libraries.
5304 A watchpoint stops execution of a program whenever the value of an
5305 expression changes. Checking for this slows down execution
5306 tremendously whenever you are in the scope of the expression, but is
5307 quite useful for catching tough ``bit-spreader'' or pointer misuse
5308 problems. Some machines such as the 386 have hardware for doing this
5309 more quickly, and future versions of gdb will use this hardware.
5311 watch EXP: Set a watchpoint (breakpoint) for an expression.
5313 info watchpoints: Information about your watchpoints.
5315 delete N: Deletes watchpoint number N (same as breakpoints).
5316 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5317 enable N: Re-enables watchpoint number N (same as breakpoints).
5320 * C++ multiple inheritance
5322 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5325 * C++ exception handling
5327 Gdb now supports limited C++ exception handling. Besides the existing
5328 ability to breakpoint on an exception handler, gdb can breakpoint on
5329 the raising of an exception (before the stack is peeled back to the
5332 catch FOO: If there is a FOO exception handler in the dynamic scope,
5333 set a breakpoint to catch exceptions which may be raised there.
5334 Multiple exceptions (``catch foo bar baz'') may be caught.
5336 info catch: Lists all exceptions which may be caught in the
5337 current stack frame.
5340 * Minor command changes
5342 The command ``call func (arg, arg, ...)'' now acts like the print
5343 command, except it does not print or save a value if the function's result
5344 is void. This is similar to dbx usage.
5346 The ``up'' and ``down'' commands now always print the frame they end up
5347 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5348 frames without printing.
5350 * New directory command
5352 'dir' now adds directories to the FRONT of the source search path.
5353 The path starts off empty. Source files that contain debug information
5354 about the directory in which they were compiled can be found even
5355 with an empty path; Sun CC and GCC include this information. If GDB can't
5356 find your source file in the current directory, type "dir .".
5358 * Configuring GDB for compilation
5360 For normal use, type ``./configure host''. See README or gdb.texinfo
5363 GDB now handles cross debugging. If you are remotely debugging between
5364 two different machines, type ``./configure host -target=targ''.
5365 Host is the machine where GDB will run; targ is the machine
5366 where the program that you are debugging will run.