1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.6
8 ** Frame filters and frame decorators have been added.
12 Nios II ELF nios2*-*-elf
13 Nios II GNU/Linux nios2*-*-linux
17 Like "catch throw", but catches a re-thrown exception.
19 Renamed from old "maint check-symtabs".
21 Perform consistency checks on symtabs.
23 Expand symtabs matching an optional regexp.
26 Display the details of GDB configure-time options.
28 maint set|show per-command
29 maint set|show per-command space
30 maint set|show per-command time
31 maint set|show per-command symtab
32 Enable display of per-command gdb resource usage.
36 set remote trace-status-packet
37 show remote trace-status-packet
38 Set/show the use of remote protocol qTStatus packet.
42 Control display of debugging messages related to Nios II targets.
46 Control whether target-assisted range stepping is enabled.
48 * You can now use a literal value 'unlimited' for options that
49 interpret 0 or -1 as meaning "unlimited". E.g., "set
50 trace-buffer-size unlimited" is now an alias for "set
51 trace-buffer-size -1" and "set height unlimited" is now an alias for
54 * New command-line options
56 Display the details of GDB configure-time options.
58 * The command 'tsave' can now support new option '-ctf' to save trace
59 buffer in Common Trace Format.
61 * Newly installed $prefix/bin/gcore acts as a shell interface for the
64 * GDB now implements the the C++ 'typeid' operator.
66 * The new convenience variable $_exception holds the exception being
67 thrown or caught at an exception-related catchpoint.
69 * The exception-related catchpoints, like "catch throw", now accept a
70 regular expression which can be used to filter exceptions by type.
74 ** The -trace-save MI command can optionally save trace buffer in Common
77 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
79 * New system-wide configuration scripts
80 A GDB installation now provides scripts suitable for use as system-wide
81 configuration scripts for the following systems:
85 * GDB now supports target-assigned range stepping with remote targets.
86 This improves the performance of stepping source lines by reducing
87 the number of control packets from/to GDB. See "New remote packets"
94 The vCont packet supports a new 'r' action, that tells the remote
95 stub to step through an address range itself, without GDB
96 involvemement at each single-step.
98 *** Changes in GDB 7.6
100 * Target record has been renamed to record-full.
101 Record/replay is now enabled with the "record full" command.
102 This also affects settings that are associated with full record/replay
103 that have been moved from "set/show record" to "set/show record full":
105 set|show record full insn-number-max
106 set|show record full stop-at-limit
107 set|show record full memory-query
109 * A new record target "record-btrace" has been added. The new target
110 uses hardware support to record the control-flow of a process. It
111 does not support replaying the execution, but it implements the
112 below new commands for investigating the recorded execution log.
113 This new recording method can be enabled using:
117 The "record-btrace" target is only available on Intel Atom processors
118 and requires a Linux kernel 2.6.32 or later.
120 * Two new commands have been added for record/replay to give information
121 about the recorded execution without having to replay the execution.
122 The commands are only supported by "record btrace".
124 record instruction-history prints the execution history at
125 instruction granularity
127 record function-call-history prints the execution history at
130 * New native configurations
132 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
133 FreeBSD/powerpc powerpc*-*-freebsd
134 x86_64/Cygwin x86_64-*-cygwin*
135 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
139 ARM AArch64 aarch64*-*-elf
140 ARM AArch64 GNU/Linux aarch64*-*-linux
141 Lynx 178 PowerPC powerpc-*-lynx*178
142 x86_64/Cygwin x86_64-*-cygwin*
143 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
145 * If the configured location of system.gdbinit file (as given by the
146 --with-system-gdbinit option at configure time) is in the
147 data-directory (as specified by --with-gdb-datadir at configure
148 time) or in one of its subdirectories, then GDB will look for the
149 system-wide init file in the directory specified by the
150 --data-directory command-line option.
152 * New command line options:
154 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
155 other initialization files, unlike -nx which disables all of them.
157 * Removed command line options
159 -epoch This was used by the gdb mode in Epoch, an ancient fork of
162 * The 'ptype' and 'whatis' commands now accept an argument to control
165 * 'info proc' now works on some core files.
169 ** Vectors can be created with gdb.Type.vector.
171 ** Python's atexit.register now works in GDB.
173 ** Types can be pretty-printed via a Python API.
175 ** Python 3 is now supported (in addition to Python 2.4 or later)
177 ** New class gdb.Architecture exposes GDB's internal representation
178 of architecture in the Python API.
180 ** New method Frame.architecture returns the gdb.Architecture object
181 corresponding to the frame's architecture.
183 * New Python-based convenience functions:
185 ** $_memeq(buf1, buf2, length)
186 ** $_streq(str1, str2)
188 ** $_regex(str, regex)
190 * The 'cd' command now defaults to using '~' (the home directory) if not
193 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
194 default for GCC since November 2000.
196 * The command 'forward-search' can now be abbreviated as 'fo'.
198 * The command 'info tracepoints' can now display 'installed on target'
199 or 'not installed on target' for each non-pending location of tracepoint.
201 * New configure options
203 --enable-libmcheck/--disable-libmcheck
204 By default, development versions are built with -lmcheck on hosts
205 that support it, in order to help track memory corruption issues.
206 Release versions, on the other hand, are built without -lmcheck
207 by default. The --enable-libmcheck/--disable-libmcheck configure
208 options allow the user to override that default.
209 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
210 This configure option allows the user to build GDB with
211 libbabeltrace using which GDB can read Common Trace Format data.
213 * New commands (for set/show, see "New options" below)
216 Catch signals. This is similar to "handle", but allows commands and
217 conditions to be attached.
220 List the BFDs known to GDB.
222 python-interactive [command]
224 Start a Python interactive prompt, or evaluate the optional command
225 and print the result of expressions.
228 "py" is a new alias for "python".
230 enable type-printer [name]...
231 disable type-printer [name]...
232 Enable or disable type printers.
236 ** For the Renesas Super-H architecture, the "regs" command has been removed
237 (has been deprecated in GDB 7.5), and "info all-registers" should be used
242 set print type methods (on|off)
243 show print type methods
244 Control whether method declarations are displayed by "ptype".
245 The default is to show them.
247 set print type typedefs (on|off)
248 show print type typedefs
249 Control whether typedef definitions are displayed by "ptype".
250 The default is to show them.
252 set filename-display basename|relative|absolute
253 show filename-display
254 Control the way in which filenames is displayed.
255 The default is "relative", which preserves previous behavior.
257 set trace-buffer-size
258 show trace-buffer-size
259 Request target to change the size of trace buffer.
261 set remote trace-buffer-size-packet auto|on|off
262 show remote trace-buffer-size-packet
263 Control the use of the remote protocol `QTBuffer:size' packet.
267 Control display of debugging messages related to ARM AArch64.
270 set debug coff-pe-read
271 show debug coff-pe-read
272 Control display of debugging messages related to reading of COFF/PE
277 Control display of debugging messages related to Mach-O symbols
280 set debug notification
281 show debug notification
282 Control display of debugging info for async remote notification.
286 ** Command parameter changes are now notified using new async record
287 "=cmd-param-changed".
288 ** Trace frame changes caused by command "tfind" are now notified using
289 new async record "=traceframe-changed".
290 ** The creation, deletion and modification of trace state variables
291 are now notified using new async records "=tsv-created",
292 "=tsv-deleted" and "=tsv-modified".
293 ** The start and stop of process record are now notified using new
294 async record "=record-started" and "=record-stopped".
295 ** Memory changes are now notified using new async record
297 ** The data-disassemble command response will include a "fullname" field
298 containing the absolute file name when source has been requested.
299 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
300 command, to allow pattern filling of memory areas.
301 ** New commands "-catch-load"/"-catch-unload" added for intercepting
302 library load/unload events.
303 ** The response to breakpoint commands and breakpoint async records
304 includes an "installed" field containing a boolean state about each
305 non-pending tracepoint location is whether installed on target or not.
306 ** Output of the "-trace-status" command includes a "trace-file" field
307 containing the name of the trace file being examined. This field is
308 optional, and only present when examining a trace file.
309 ** The "fullname" field is now always present along with the "file" field,
310 even if the file cannot be found by GDB.
312 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
313 You must have the LZMA library available when configuring GDB for this
314 feature to be enabled. For more information, see:
315 http://fedoraproject.org/wiki/Features/MiniDebugInfo
320 Set the size of trace buffer. The remote stub reports support for this
321 packet to gdb's qSupported query.
324 Enable Branch Trace Store (BTS)-based branch tracing for the current
325 thread. The remote stub reports support for this packet to gdb's
329 Disable branch tracing for the current thread. The remote stub reports
330 support for this packet to gdb's qSupported query.
333 Read the traced branches for the current thread. The remote stub
334 reports support for this packet to gdb's qSupported query.
336 *** Changes in GDB 7.5
338 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
339 for more x32 ABI info.
341 * GDB now supports access to MIPS DSP registers on Linux targets.
343 * GDB now supports debugging microMIPS binaries.
345 * The "info os" command on GNU/Linux can now display information on
346 several new classes of objects managed by the operating system:
347 "info os procgroups" lists process groups
348 "info os files" lists file descriptors
349 "info os sockets" lists internet-domain sockets
350 "info os shm" lists shared-memory regions
351 "info os semaphores" lists semaphores
352 "info os msg" lists message queues
353 "info os modules" lists loaded kernel modules
355 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
356 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
357 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
358 options and inspect the probe arguments using the new $_probe_arg family
359 of convenience variables. You can obtain more information about SystemTap
360 in <http://sourceware.org/systemtap/>.
362 * GDB now supports reversible debugging on ARM, it allows you to
363 debug basic ARM and THUMB instructions, and provides
364 record/replay support.
366 * The option "symbol-reloading" has been deleted as it is no longer used.
370 ** GDB commands implemented in Python can now be put in command class
373 ** The "maint set python print-stack on|off" is now deleted.
375 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
376 apply "flag enum"-style pretty-printing to any enum.
378 ** gdb.lookup_symbol can now work when there is no current frame.
380 ** gdb.Symbol now has a 'line' attribute, holding the line number in
381 the source at which the symbol was defined.
383 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
384 method 'value'. The former indicates whether the symbol needs a
385 frame in order to compute its value, and the latter computes the
388 ** A new method 'referenced_value' on gdb.Value objects which can
389 dereference pointer as well as C++ reference values.
391 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
392 which return the global and static blocks (as gdb.Block objects),
393 of the underlying symbol table, respectively.
395 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
396 object associated with a PC value.
398 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
399 of the address range occupied by code for the current source line.
401 * Go language support.
402 GDB now supports debugging programs written in the Go programming
405 * GDBserver now supports stdio connections.
406 E.g. (gdb) target remote | ssh myhost gdbserver - hello
408 * The binary "gdbtui" can no longer be built or installed.
409 Use "gdb -tui" instead.
411 * GDB will now print "flag" enums specially. A flag enum is one where
412 all the enumerator values have no bits in common when pairwise
413 "and"ed. When printing a value whose type is a flag enum, GDB will
414 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
415 (gdb) print (enum E) 3
418 * The filename part of a linespec will now match trailing components
419 of a source file name. For example, "break gcc/expr.c:1000" will
420 now set a breakpoint in build/gcc/expr.c, but not
423 * The "info proc" and "generate-core-file" commands will now also
424 work on remote targets connected to GDBserver on Linux.
426 * The command "info catch" has been removed. It has been disabled
429 * The "catch exception" and "catch assert" commands now accept
430 a condition at the end of the command, much like the "break"
431 command does. For instance:
433 (gdb) catch exception Constraint_Error if Barrier = True
435 Previously, it was possible to add a condition to such catchpoints,
436 but it had to be done as a second step, after the catchpoint had been
437 created, using the "condition" command.
439 * The "info static-tracepoint-marker" command will now also work on
440 native Linux targets with in-process agent.
442 * GDB can now set breakpoints on inlined functions.
444 * The .gdb_index section has been updated to include symbols for
445 inlined functions. GDB will ignore older .gdb_index sections by
446 default, which could cause symbol files to be loaded more slowly
447 until their .gdb_index sections can be recreated. The new command
448 "set use-deprecated-index-sections on" will cause GDB to use any older
449 .gdb_index sections it finds. This will restore performance, but the
450 ability to set breakpoints on inlined functions will be lost in symbol
451 files with older .gdb_index sections.
453 The .gdb_index section has also been updated to record more information
454 about each symbol. This speeds up the "info variables", "info functions"
455 and "info types" commands when used with programs having the .gdb_index
456 section, as well as speeding up debugging with shared libraries using
457 the .gdb_index section.
459 * Ada support for GDB/MI Variable Objects has been added.
461 * GDB can now support 'breakpoint always-inserted mode' in 'record'
466 ** New command -info-os is the MI equivalent of "info os".
468 ** Output logs ("set logging" and related) now include MI output.
472 ** "set use-deprecated-index-sections on|off"
473 "show use-deprecated-index-sections on|off"
474 Controls the use of deprecated .gdb_index sections.
476 ** "catch load" and "catch unload" can be used to stop when a shared
477 library is loaded or unloaded, respectively.
479 ** "enable count" can be used to auto-disable a breakpoint after
482 ** "info vtbl" can be used to show the virtual method tables for
483 C++ and Java objects.
485 ** "explore" and its sub commands "explore value" and "explore type"
486 can be used to reccursively explore values and types of
487 expressions. These commands are available only if GDB is
488 configured with '--with-python'.
490 ** "info auto-load" shows status of all kinds of auto-loaded files,
491 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
492 sequences of commands files, "info auto-load python-scripts"
493 shows status of auto-loading Python script files,
494 "info auto-load local-gdbinit" shows status of loading init file
495 (.gdbinit) from current directory and "info auto-load libthread-db" shows
496 status of inferior specific thread debugging shared library loading.
498 ** "info auto-load-scripts", "set auto-load-scripts on|off"
499 and "show auto-load-scripts" commands have been deprecated, use their
500 "info auto-load python-scripts", "set auto-load python-scripts on|off"
501 and "show auto-load python-scripts" counterparts instead.
503 ** "dprintf location,format,args..." creates a dynamic printf, which
504 is basically a breakpoint that does a printf and immediately
505 resumes your program's execution, so it is like a printf that you
506 can insert dynamically at runtime instead of at compiletime.
508 ** "set print symbol"
510 Controls whether GDB attempts to display the symbol, if any,
511 corresponding to addresses it prints. This defaults to "on", but
512 you can set it to "off" to restore GDB's previous behavior.
514 * Deprecated commands
516 ** For the Renesas Super-H architecture, the "regs" command has been
517 deprecated, and "info all-registers" should be used instead.
521 Renesas RL78 rl78-*-elf
522 HP OpenVMS ia64 ia64-hp-openvms*
524 * GDBserver supports evaluation of breakpoint conditions. When
525 support is advertised by GDBserver, GDB may be told to send the
526 breakpoint conditions in bytecode form to GDBserver. GDBserver
527 will only report the breakpoint trigger to GDB when its condition
533 show mips compression
534 Select the compressed ISA encoding used in functions that have no symbol
535 information available. The encoding can be set to either of:
538 and is updated automatically from ELF file flags if available.
540 set breakpoint condition-evaluation
541 show breakpoint condition-evaluation
542 Control whether breakpoint conditions are evaluated by GDB ("host") or by
543 GDBserver ("target"). Default option "auto" chooses the most efficient
545 This option can improve debugger efficiency depending on the speed of the
549 Disable auto-loading globally.
552 Show auto-loading setting of all kinds of auto-loaded files.
554 set auto-load gdb-scripts on|off
555 show auto-load gdb-scripts
556 Control auto-loading of GDB canned sequences of commands files.
558 set auto-load python-scripts on|off
559 show auto-load python-scripts
560 Control auto-loading of Python script files.
562 set auto-load local-gdbinit on|off
563 show auto-load local-gdbinit
564 Control loading of init file (.gdbinit) from current directory.
566 set auto-load libthread-db on|off
567 show auto-load libthread-db
568 Control auto-loading of inferior specific thread debugging shared library.
570 set auto-load scripts-directory <dir1>[:<dir2>...]
571 show auto-load scripts-directory
572 Set a list of directories from which to load auto-loaded scripts.
573 Automatically loaded Python scripts and GDB scripts are located in one
574 of the directories listed by this option.
575 The delimiter (':' above) may differ according to the host platform.
577 set auto-load safe-path <dir1>[:<dir2>...]
578 show auto-load safe-path
579 Set a list of directories from which it is safe to auto-load files.
580 The delimiter (':' above) may differ according to the host platform.
582 set debug auto-load on|off
584 Control display of debugging info for auto-loading the files above.
586 set dprintf-style gdb|call|agent
588 Control the way in which a dynamic printf is performed; "gdb"
589 requests a GDB printf command, while "call" causes dprintf to call a
590 function in the inferior. "agent" requests that the target agent
591 (such as GDBserver) do the printing.
593 set dprintf-function <expr>
594 show dprintf-function
595 set dprintf-channel <expr>
597 Set the function and optional first argument to the call when using
598 the "call" style of dynamic printf.
600 set disconnected-dprintf on|off
601 show disconnected-dprintf
602 Control whether agent-style dynamic printfs continue to be in effect
603 after GDB disconnects.
605 * New configure options
608 Configure default value for the 'set auto-load scripts-directory'
609 setting above. It defaults to '$debugdir:$datadir/auto-load',
610 $debugdir representing global debugging info directories (available
611 via 'show debug-file-directory') and $datadir representing GDB's data
612 directory (available via 'show data-directory').
614 --with-auto-load-safe-path
615 Configure default value for the 'set auto-load safe-path' setting
616 above. It defaults to the --with-auto-load-dir setting.
618 --without-auto-load-safe-path
619 Set 'set auto-load safe-path' to '/', effectively disabling this
624 z0/z1 conditional breakpoints extension
626 The z0/z1 breakpoint insertion packets have been extended to carry
627 a list of conditional expressions over to the remote stub depending on the
628 condition evaluation mode. The use of this extension can be controlled
629 via the "set remote conditional-breakpoints-packet" command.
633 Specify the signals which the remote stub may pass to the debugged
634 program without GDB involvement.
636 * New command line options
638 --init-command=FILE, -ix Like --command, -x but execute it
639 before loading inferior.
640 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
641 execute it before loading inferior.
643 *** Changes in GDB 7.4
645 * GDB now handles ambiguous linespecs more consistently; the existing
646 FILE:LINE support has been expanded to other types of linespecs. A
647 breakpoint will now be set on all matching locations in all
648 inferiors, and locations will be added or removed according to
651 * GDB now allows you to skip uninteresting functions and files when
652 stepping with the "skip function" and "skip file" commands.
654 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
655 and "show remote hardware-watchpoint-length-limit". These allows to
656 set or show the maximum length limit (in bytes) of a remote
657 target hardware watchpoint.
659 This allows e.g. to use "unlimited" hardware watchpoints with the
660 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
661 watchpoints are slower than real hardware watchpoints but are
662 significantly faster than gdb software watchpoints.
666 ** The register_pretty_printer function in module gdb.printing now takes
667 an optional `replace' argument. If True, the new printer replaces any
670 ** The "maint set python print-stack on|off" command has been
671 deprecated and will be deleted in GDB 7.5.
672 A new command: "set python print-stack none|full|message" has
673 replaced it. Additionally, the default for "print-stack" is
674 now "message", which just prints the error message without
677 ** A prompt substitution hook (prompt_hook) is now available to the
680 ** A new Python module, gdb.prompt has been added to the GDB Python
681 modules library. This module provides functionality for
682 escape sequences in prompts (used by set/show
683 extended-prompt). These escape sequences are replaced by their
686 ** Python commands and convenience-functions located in
687 'data-directory'/python/gdb/command and
688 'data-directory'/python/gdb/function are now automatically loaded
691 ** Blocks now provide four new attributes. global_block and
692 static_block will return the global and static blocks
693 respectively. is_static and is_global are boolean attributes
694 that indicate if the block is one of those two types.
696 ** Symbols now provide the "type" attribute, the type of the symbol.
698 ** The "gdb.breakpoint" function has been deprecated in favor of
701 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
702 of a function. This class is based on the "finish" command
703 available in the CLI.
705 ** Type objects for struct and union types now allow access to
706 the fields using standard Python dictionary (mapping) methods.
707 For example, "some_type['myfield']" now works, as does
710 ** A new event "gdb.new_objfile" has been added, triggered by loading a
713 ** A new function, "deep_items" has been added to the gdb.types
714 module in the GDB Python modules library. This function returns
715 an iterator over the fields of a struct or union type. Unlike
716 the standard Python "iteritems" method, it will recursively traverse
717 any anonymous fields.
721 ** "*stopped" events can report several new "reason"s, such as
724 ** Breakpoint changes are now notified using new async records, like
725 "=breakpoint-modified".
727 ** New command -ada-task-info.
729 * libthread-db-search-path now supports two special values: $sdir and $pdir.
730 $sdir specifies the default system locations of shared libraries.
731 $pdir specifies the directory where the libpthread used by the application
734 GDB no longer looks in $sdir and $pdir after it has searched the directories
735 mentioned in libthread-db-search-path. If you want to search those
736 directories, they must be specified in libthread-db-search-path.
737 The default value of libthread-db-search-path on GNU/Linux and Solaris
738 systems is now "$sdir:$pdir".
740 $pdir is not supported by gdbserver, it is currently ignored.
741 $sdir is supported by gdbserver.
743 * New configure option --with-iconv-bin.
744 When using the internationalization support like the one in the GNU C
745 library, GDB will invoke the "iconv" program to get a list of supported
746 character sets. If this program lives in a non-standard location, one can
747 use this option to specify where to find it.
749 * When natively debugging programs on PowerPC BookE processors running
750 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
751 watchpoints, which specify a mask in addition to an address to watch.
752 The mask specifies that some bits of an address (the bits which are
753 reset in the mask) should be ignored when matching the address accessed
754 by the inferior against the watchpoint address. See the "PowerPC Embedded"
755 section in the user manual for more details.
757 * The new option --once causes GDBserver to stop listening for connections once
758 the first connection is made. The listening port used by GDBserver will
759 become available after that.
761 * New commands "info macros" and "alias" have been added.
763 * New function parameters suffix @entry specifies value of function parameter
764 at the time the function got called. Entry values are available only since
770 "!" is now an alias of the "shell" command.
771 Note that no space is needed between "!" and SHELL COMMAND.
775 watch EXPRESSION mask MASK_VALUE
776 The watch command now supports the mask argument which allows creation
777 of masked watchpoints, if the current architecture supports this feature.
779 info auto-load-scripts [REGEXP]
780 This command was formerly named "maintenance print section-scripts".
781 It is now generally useful and is no longer a maintenance-only command.
783 info macro [-all] [--] MACRO
784 The info macro command has new options `-all' and `--'. The first for
785 printing all definitions of a macro. The second for explicitly specifying
786 the end of arguments and the beginning of the macro name in case the macro
787 name starts with a hyphen.
789 collect[/s] EXPRESSIONS
790 The tracepoint collect command now takes an optional modifier "/s"
791 that directs it to dereference pointer-to-character types and
792 collect the bytes of memory up to a zero byte. The behavior is
793 similar to what you see when you use the regular print command on a
794 string. An optional integer following the "/s" sets a bound on the
795 number of bytes that will be collected.
798 The trace start command now interprets any supplied arguments as a
799 note to be recorded with the trace run, with an effect similar to
800 setting the variable trace-notes.
803 The trace stop command now interprets any arguments as a note to be
804 mentioned along with the tstatus report that the trace was stopped
805 with a command. The effect is similar to setting the variable
808 * Tracepoints can now be enabled and disabled at any time after a trace
809 experiment has been started using the standard "enable" and "disable"
810 commands. It is now possible to start a trace experiment with no enabled
811 tracepoints; GDB will display a warning, but will allow the experiment to
812 begin, assuming that tracepoints will be enabled as needed while the trace
815 * Fast tracepoints on 32-bit x86-architectures can now be placed at
816 locations with 4-byte instructions, when they were previously
817 limited to locations with instructions of 5 bytes or longer.
821 set debug dwarf2-read
822 show debug dwarf2-read
823 Turns on or off display of debugging messages related to reading
824 DWARF debug info. The default is off.
826 set debug symtab-create
827 show debug symtab-create
828 Turns on or off display of debugging messages related to symbol table
829 creation. The default is off.
833 Set the GDB prompt, and allow escape sequences to be inserted to
834 display miscellaneous information (see 'help set extended-prompt'
835 for the list of sequences). This prompt (and any information
836 accessed through the escape sequences) is updated every time the
839 set print entry-values (both|compact|default|if-needed|no|only|preferred)
840 show print entry-values
841 Set printing of frame argument values at function entry. In some cases
842 GDB can determine the value of function argument which was passed by the
843 function caller, even if the value was modified inside the called function.
845 set debug entry-values
846 show debug entry-values
847 Control display of debugging info for determining frame argument values at
848 function entry and virtual tail call frames.
850 set basenames-may-differ
851 show basenames-may-differ
852 Set whether a source file may have multiple base names.
853 (A "base name" is the name of a file with the directory part removed.
854 Example: The base name of "/home/user/hello.c" is "hello.c".)
855 If set, GDB will canonicalize file names (e.g., expand symlinks)
856 before comparing them. Canonicalization is an expensive operation,
857 but it allows the same file be known by more than one base name.
858 If not set (the default), all source files are assumed to have just
859 one base name, and gdb will do file name comparisons more efficiently.
865 Set a user name and notes for the current and any future trace runs.
866 This is useful for long-running and/or disconnected traces, to
867 inform others (or yourself) as to who is running the trace, supply
868 contact information, or otherwise explain what is going on.
871 show trace-stop-notes
872 Set a note attached to the trace run, that is displayed when the
873 trace has been stopped by a tstop command. This is useful for
874 instance as an explanation, if you are stopping a trace run that was
875 started by someone else.
881 Dynamically enable a tracepoint in a started trace experiment.
885 Dynamically disable a tracepoint in a started trace experiment.
889 Set the user and notes of the trace run.
893 Query the current status of a tracepoint.
897 Query the minimum length of instruction at which a fast tracepoint may
900 * Dcache size (number of lines) and line-size are now runtime-configurable
901 via "set dcache line" and "set dcache line-size" commands.
905 Texas Instruments TMS320C6x tic6x-*-*
909 Renesas RL78 rl78-*-elf
911 *** Changes in GDB 7.3.1
913 * The build failure for NetBSD and OpenBSD targets have now been fixed.
915 *** Changes in GDB 7.3
917 * GDB has a new command: "thread find [REGEXP]".
918 It finds the thread id whose name, target id, or thread extra info
919 matches the given regular expression.
921 * The "catch syscall" command now works on mips*-linux* targets.
923 * The -data-disassemble MI command now supports modes 2 and 3 for
924 dumping the instruction opcodes.
926 * New command line options
928 -data-directory DIR Specify DIR as the "data-directory".
929 This is mostly for testing purposes.
931 * The "maint set python auto-load on|off" command has been renamed to
932 "set auto-load-scripts on|off".
934 * GDB has a new command: "set directories".
935 It is like the "dir" command except that it replaces the
936 source path list instead of augmenting it.
938 * GDB now understands thread names.
940 On GNU/Linux, "info threads" will display the thread name as set by
941 prctl or pthread_setname_np.
943 There is also a new command, "thread name", which can be used to
944 assign a name internally for GDB to display.
947 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
948 has been integrated into GDB.
952 ** The function gdb.Write now accepts an optional keyword 'stream'.
953 This keyword, when provided, will direct the output to either
954 stdout, stderr, or GDB's logging output.
956 ** Parameters can now be be sub-classed in Python, and in particular
957 you may implement the get_set_doc and get_show_doc functions.
958 This improves how Parameter set/show documentation is processed
959 and allows for more dynamic content.
961 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
962 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
963 have an is_valid method.
965 ** Breakpoints can now be sub-classed in Python, and in particular
966 you may implement a 'stop' function that is executed each time
967 the inferior reaches that breakpoint.
969 ** New function gdb.lookup_global_symbol looks up a global symbol.
971 ** GDB values in Python are now callable if the value represents a
972 function. For example, if 'some_value' represents a function that
973 takes two integer parameters and returns a value, you can call
974 that function like so:
976 result = some_value (10,20)
978 ** Module gdb.types has been added.
979 It contains a collection of utilities for working with gdb.Types objects:
980 get_basic_type, has_field, make_enum_dict.
982 ** Module gdb.printing has been added.
983 It contains utilities for writing and registering pretty-printers.
984 New classes: PrettyPrinter, SubPrettyPrinter,
985 RegexpCollectionPrettyPrinter.
986 New function: register_pretty_printer.
988 ** New commands "info pretty-printers", "enable pretty-printer" and
989 "disable pretty-printer" have been added.
991 ** gdb.parameter("directories") is now available.
993 ** New function gdb.newest_frame returns the newest frame in the
996 ** The gdb.InferiorThread class has a new "name" attribute. This
997 holds the thread's name.
999 ** Python Support for Inferior events.
1000 Python scripts can add observers to be notified of events
1001 occurring in the process being debugged.
1002 The following events are currently supported:
1003 - gdb.events.cont Continue event.
1004 - gdb.events.exited Inferior exited event.
1005 - gdb.events.stop Signal received, and Breakpoint hit events.
1009 ** GDB now puts template parameters in scope when debugging in an
1010 instantiation. For example, if you have:
1012 template<int X> int func (void) { return X; }
1014 then if you step into func<5>, "print X" will show "5". This
1015 feature requires proper debuginfo support from the compiler; it
1016 was added to GCC 4.5.
1018 ** The motion commands "next", "finish", "until", and "advance" now
1019 work better when exceptions are thrown. In particular, GDB will
1020 no longer lose control of the inferior; instead, the GDB will
1021 stop the inferior at the point at which the exception is caught.
1022 This functionality requires a change in the exception handling
1023 code that was introduced in GCC 4.5.
1025 * GDB now follows GCC's rules on accessing volatile objects when
1026 reading or writing target state during expression evaluation.
1027 One notable difference to prior behavior is that "print x = 0"
1028 no longer generates a read of x; the value of the assignment is
1029 now always taken directly from the value being assigned.
1031 * GDB now has some support for using labels in the program's source in
1032 linespecs. For instance, you can use "advance label" to continue
1033 execution to a label.
1035 * GDB now has support for reading and writing a new .gdb_index
1036 section. This section holds a fast index of DWARF debugging
1037 information and can be used to greatly speed up GDB startup and
1038 operation. See the documentation for `save gdb-index' for details.
1040 * The "watch" command now accepts an optional "-location" argument.
1041 When used, this causes GDB to watch the memory referred to by the
1042 expression. Such a watchpoint is never deleted due to it going out
1045 * GDB now supports thread debugging of core dumps on GNU/Linux.
1047 GDB now activates thread debugging using the libthread_db library
1048 when debugging GNU/Linux core dumps, similarly to when debugging
1049 live processes. As a result, when debugging a core dump file, GDB
1050 is now able to display pthread_t ids of threads. For example, "info
1051 threads" shows the same output as when debugging the process when it
1052 was live. In earlier releases, you'd see something like this:
1055 * 1 LWP 6780 main () at main.c:10
1057 While now you see this:
1060 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1062 It is also now possible to inspect TLS variables when debugging core
1065 When debugging a core dump generated on a machine other than the one
1066 used to run GDB, you may need to point GDB at the correct
1067 libthread_db library with the "set libthread-db-search-path"
1068 command. See the user manual for more details on this command.
1070 * When natively debugging programs on PowerPC BookE processors running
1071 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1072 which stop execution of the inferior whenever it executes an instruction
1073 at any address within the specified range. See the "PowerPC Embedded"
1074 section in the user manual for more details.
1076 * New features in the GDB remote stub, GDBserver
1078 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1079 and i686 LynxOS (version 5.x).
1081 ** GDBserver is now supported on Blackfin Linux.
1083 * New native configurations
1085 ia64 HP-UX ia64-*-hpux*
1089 Analog Devices, Inc. Blackfin Processor bfin-*
1091 * Ada task switching is now supported on sparc-elf targets when
1092 debugging a program using the Ravenscar Profile. For more information,
1093 see the "Tasking Support when using the Ravenscar Profile" section
1094 in the GDB user manual.
1096 * Guile support was removed.
1098 * New features in the GNU simulator
1100 ** The --map-info flag lists all known core mappings.
1102 ** CFI flashes may be simulated via the "cfi" device.
1104 *** Changes in GDB 7.2
1106 * Shared library support for remote targets by default
1108 When GDB is configured for a generic, non-OS specific target, like
1109 for example, --target=arm-eabi or one of the many *-*-elf targets,
1110 GDB now queries remote stubs for loaded shared libraries using the
1111 `qXfer:libraries:read' packet. Previously, shared library support
1112 was always disabled for such configurations.
1116 ** Argument Dependent Lookup (ADL)
1118 In C++ ADL lookup directs function search to the namespaces of its
1119 arguments even if the namespace has not been imported.
1129 Here the compiler will search for `foo' in the namespace of 'b'
1130 and find A::foo. GDB now supports this. This construct is commonly
1131 used in the Standard Template Library for operators.
1133 ** Improved User Defined Operator Support
1135 In addition to member operators, GDB now supports lookup of operators
1136 defined in a namespace and imported with a `using' directive, operators
1137 defined in the global scope, operators imported implicitly from an
1138 anonymous namespace, and the ADL operators mentioned in the previous
1140 GDB now also supports proper overload resolution for all the previously
1141 mentioned flavors of operators.
1143 ** static const class members
1145 Printing of static const class members that are initialized in the
1146 class definition has been fixed.
1148 * Windows Thread Information Block access.
1150 On Windows targets, GDB now supports displaying the Windows Thread
1151 Information Block (TIB) structure. This structure is visible either
1152 by using the new command `info w32 thread-information-block' or, by
1153 dereferencing the new convenience variable named `$_tlb', a
1154 thread-specific pointer to the TIB. This feature is also supported
1155 when remote debugging using GDBserver.
1157 * Static tracepoints
1159 Static tracepoints are calls in the user program into a tracing
1160 library. One such library is a port of the LTTng kernel tracer to
1161 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1162 When debugging with GDBserver, GDB now supports combining the GDB
1163 tracepoint machinery with such libraries. For example: the user can
1164 use GDB to probe a static tracepoint marker (a call from the user
1165 program into the tracing library) with the new "strace" command (see
1166 "New commands" below). This creates a "static tracepoint" in the
1167 breakpoint list, that can be manipulated with the same feature set
1168 as fast and regular tracepoints. E.g., collect registers, local and
1169 global variables, collect trace state variables, and define
1170 tracepoint conditions. In addition, the user can collect extra
1171 static tracepoint marker specific data, by collecting the new
1172 $_sdata internal variable. When analyzing the trace buffer, you can
1173 inspect $_sdata like any other variable available to GDB. For more
1174 information, see the "Tracepoints" chapter in GDB user manual. New
1175 remote packets have been defined to support static tracepoints, see
1176 the "New remote packets" section below.
1178 * Better reconstruction of tracepoints after disconnected tracing
1180 GDB will attempt to download the original source form of tracepoint
1181 definitions when starting a trace run, and then will upload these
1182 upon reconnection to the target, resulting in a more accurate
1183 reconstruction of the tracepoints that are in use on the target.
1187 You can now exercise direct control over the ways that GDB can
1188 affect your program. For instance, you can disallow the setting of
1189 breakpoints, so that the program can run continuously (assuming
1190 non-stop mode). In addition, the "observer" variable is available
1191 to switch all of the different controls; in observer mode, GDB
1192 cannot affect the target's behavior at all, which is useful for
1193 tasks like diagnosing live systems in the field.
1195 * The new convenience variable $_thread holds the number of the
1198 * New remote packets
1202 Return the address of the Windows Thread Information Block of a given thread.
1206 In response to several of the tracepoint packets, the target may now
1207 also respond with a number of intermediate `qRelocInsn' request
1208 packets before the final result packet, to have GDB handle
1209 relocating an instruction to execute at a different address. This
1210 is particularly useful for stubs that support fast tracepoints. GDB
1211 reports support for this feature in the qSupported packet.
1215 List static tracepoint markers in the target program.
1219 List static tracepoint markers at a given address in the target
1222 qXfer:statictrace:read
1224 Read the static trace data collected (by a `collect $_sdata'
1225 tracepoint action). The remote stub reports support for this packet
1226 to gdb's qSupported query.
1230 Send the current settings of GDB's permission flags.
1234 Send part of the source (textual) form of a tracepoint definition,
1235 which includes location, conditional, and action list.
1237 * The source command now accepts a -s option to force searching for the
1238 script in the source search path even if the script name specifies
1241 * New features in the GDB remote stub, GDBserver
1243 - GDBserver now support tracepoints (including fast tracepoints, and
1244 static tracepoints). The feature is currently supported by the
1245 i386-linux and amd64-linux builds. See the "Tracepoints support
1246 in gdbserver" section in the manual for more information.
1248 GDBserver JIT compiles the tracepoint's conditional agent
1249 expression bytecode into native code whenever possible for low
1250 overhead dynamic tracepoints conditionals. For such tracepoints,
1251 an expression that examines program state is evaluated when the
1252 tracepoint is reached, in order to determine whether to capture
1253 trace data. If the condition is simple and false, processing the
1254 tracepoint finishes very quickly and no data is gathered.
1256 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1257 for static tracepoints support.
1259 - GDBserver now supports x86_64 Windows 64-bit debugging.
1261 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1262 it understands register description.
1264 * The --batch flag now disables pagination and queries.
1266 * X86 general purpose registers
1268 GDB now supports reading/writing byte, word and double-word x86
1269 general purpose registers directly. This means you can use, say,
1270 $ah or $ax to refer, respectively, to the byte register AH and
1271 16-bit word register AX that are actually portions of the 32-bit
1272 register EAX or 64-bit register RAX.
1274 * The `commands' command now accepts a range of breakpoints to modify.
1275 A plain `commands' following a command that creates multiple
1276 breakpoints affects all the breakpoints set by that command. This
1277 applies to breakpoints set by `rbreak', and also applies when a
1278 single `break' command creates multiple breakpoints (e.g.,
1279 breakpoints on overloaded c++ functions).
1281 * The `rbreak' command now accepts a filename specification as part of
1282 its argument, limiting the functions selected by the regex to those
1283 in the specified file.
1285 * Support for remote debugging Windows and SymbianOS shared libraries
1286 from Unix hosts has been improved. Non Windows GDB builds now can
1287 understand target reported file names that follow MS-DOS based file
1288 system semantics, such as file names that include drive letters and
1289 use the backslash character as directory separator. This makes it
1290 possible to transparently use the "set sysroot" and "set
1291 solib-search-path" on Unix hosts to point as host copies of the
1292 target's shared libraries. See the new command "set
1293 target-file-system-kind" described below, and the "Commands to
1294 specify files" section in the user manual for more information.
1298 eval template, expressions...
1299 Convert the values of one or more expressions under the control
1300 of the string template to a command line, and call it.
1302 set target-file-system-kind unix|dos-based|auto
1303 show target-file-system-kind
1304 Set or show the assumed file system kind for target reported file
1307 save breakpoints <filename>
1308 Save all current breakpoint definitions to a file suitable for use
1309 in a later debugging session. To read the saved breakpoint
1310 definitions, use the `source' command.
1312 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1315 info static-tracepoint-markers
1316 Display information about static tracepoint markers in the target.
1318 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1319 Define a static tracepoint by probing a marker at the given
1320 function, line, address, or marker ID.
1324 Enable and disable observer mode.
1326 set may-write-registers on|off
1327 set may-write-memory on|off
1328 set may-insert-breakpoints on|off
1329 set may-insert-tracepoints on|off
1330 set may-insert-fast-tracepoints on|off
1331 set may-interrupt on|off
1332 Set individual permissions for GDB effects on the target. Note that
1333 some of these settings can have undesirable or surprising
1334 consequences, particularly when changed in the middle of a session.
1335 For instance, disabling the writing of memory can prevent
1336 breakpoints from being inserted, cause single-stepping to fail, or
1337 even crash your program, if you disable after breakpoints have been
1338 inserted. However, GDB should not crash.
1340 set record memory-query on|off
1341 show record memory-query
1342 Control whether to stop the inferior if memory changes caused
1343 by an instruction cannot be recorded.
1348 The disassemble command now supports "start,+length" form of two arguments.
1352 ** GDB now provides a new directory location, called the python directory,
1353 where Python scripts written for GDB can be installed. The location
1354 of that directory is <data-directory>/python, where <data-directory>
1355 is the GDB data directory. For more details, see section `Scripting
1356 GDB using Python' in the manual.
1358 ** The GDB Python API now has access to breakpoints, symbols, symbol
1359 tables, program spaces, inferiors, threads and frame's code blocks.
1360 Additionally, GDB Parameters can now be created from the API, and
1361 manipulated via set/show in the CLI.
1363 ** New functions gdb.target_charset, gdb.target_wide_charset,
1364 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1366 ** New exception gdb.GdbError.
1368 ** Pretty-printers are now also looked up in the current program space.
1370 ** Pretty-printers can now be individually enabled and disabled.
1372 ** GDB now looks for names of Python scripts to auto-load in a
1373 special section named `.debug_gdb_scripts', in addition to looking
1374 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1376 * Tracepoint actions were unified with breakpoint commands. In particular,
1377 there are no longer differences in "info break" output for breakpoints and
1378 tracepoints and the "commands" command can be used for both tracepoints and
1379 regular breakpoints.
1383 ARM Symbian arm*-*-symbianelf*
1385 * D language support.
1386 GDB now supports debugging programs written in the D programming
1389 * GDB now supports the extended ptrace interface for PowerPC which is
1390 available since Linux kernel version 2.6.34. This automatically enables
1391 any hardware breakpoints and additional hardware watchpoints available in
1392 the processor. The old ptrace interface exposes just one hardware
1393 watchpoint and no hardware breakpoints.
1395 * GDB is now able to use the Data Value Compare (DVC) register available on
1396 embedded PowerPC processors to implement in hardware simple watchpoint
1397 conditions of the form:
1399 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1401 This works in native GDB running on Linux kernels with the extended ptrace
1402 interface mentioned above.
1404 *** Changes in GDB 7.1
1408 ** Namespace Support
1410 GDB now supports importing of namespaces in C++. This enables the
1411 user to inspect variables from imported namespaces. Support for
1412 namepace aliasing has also been added. So, if a namespace is
1413 aliased in the current scope (e.g. namepace C=A; ) the user can
1414 print variables using the alias (e.g. (gdb) print C::x).
1418 All known bugs relating to the printing of virtual base class were
1419 fixed. It is now possible to call overloaded static methods using a
1424 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1425 and reinterpret_cast<> are now handled by the C++ expression parser.
1429 Xilinx MicroBlaze microblaze-*-*
1434 Xilinx MicroBlaze microblaze
1437 * Multi-program debugging.
1439 GDB now has support for multi-program (a.k.a. multi-executable or
1440 multi-exec) debugging. This allows for debugging multiple inferiors
1441 simultaneously each running a different program under the same GDB
1442 session. See "Debugging Multiple Inferiors and Programs" in the
1443 manual for more information. This implied some user visible changes
1444 in the multi-inferior support. For example, "info inferiors" now
1445 lists inferiors that are not running yet or that have exited
1446 already. See also "New commands" and "New options" below.
1448 * New tracing features
1450 GDB's tracepoint facility now includes several new features:
1452 ** Trace state variables
1454 GDB tracepoints now include support for trace state variables, which
1455 are variables managed by the target agent during a tracing
1456 experiment. They are useful for tracepoints that trigger each
1457 other, so for instance one tracepoint can count hits in a variable,
1458 and then a second tracepoint has a condition that is true when the
1459 count reaches a particular value. Trace state variables share the
1460 $-syntax of GDB convenience variables, and can appear in both
1461 tracepoint actions and condition expressions. Use the "tvariable"
1462 command to create, and "info tvariables" to view; see "Trace State
1463 Variables" in the manual for more detail.
1467 GDB now includes an option for defining fast tracepoints, which
1468 targets may implement more efficiently, such as by installing a jump
1469 into the target agent rather than a trap instruction. The resulting
1470 speedup can be by two orders of magnitude or more, although the
1471 tradeoff is that some program locations on some target architectures
1472 might not allow fast tracepoint installation, for instance if the
1473 instruction to be replaced is shorter than the jump. To request a
1474 fast tracepoint, use the "ftrace" command, with syntax identical to
1475 the regular trace command.
1477 ** Disconnected tracing
1479 It is now possible to detach GDB from the target while it is running
1480 a trace experiment, then reconnect later to see how the experiment
1481 is going. In addition, a new variable disconnected-tracing lets you
1482 tell the target agent whether to continue running a trace if the
1483 connection is lost unexpectedly.
1487 GDB now has the ability to save the trace buffer into a file, and
1488 then use that file as a target, similarly to you can do with
1489 corefiles. You can select trace frames, print data that was
1490 collected in them, and use tstatus to display the state of the
1491 tracing run at the moment that it was saved. To create a trace
1492 file, use "tsave <filename>", and to use it, do "target tfile
1495 ** Circular trace buffer
1497 You can ask the target agent to handle the trace buffer as a
1498 circular buffer, discarding the oldest trace frames to make room for
1499 newer ones, by setting circular-trace-buffer to on. This feature may
1500 not be available for all target agents.
1505 The disassemble command, when invoked with two arguments, now requires
1506 the arguments to be comma-separated.
1509 The info variables command now displays variable definitions. Files
1510 which only declare a variable are not shown.
1513 The source command is now capable of sourcing Python scripts.
1514 This feature is dependent on the debugger being build with Python
1517 Related to this enhancement is also the introduction of a new command
1518 "set script-extension" (see below).
1520 * New commands (for set/show, see "New options" below)
1522 record save [<FILENAME>]
1523 Save a file (in core file format) containing the process record
1524 execution log for replay debugging at a later time.
1526 record restore <FILENAME>
1527 Restore the process record execution log that was saved at an
1528 earlier time, for replay debugging.
1530 add-inferior [-copies <N>] [-exec <FILENAME>]
1533 clone-inferior [-copies <N>] [ID]
1534 Make a new inferior ready to execute the same program another
1535 inferior has loaded.
1540 maint info program-spaces
1541 List the program spaces loaded into GDB.
1543 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1544 show remote interrupt-sequence
1545 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1546 as the sequence to the remote target in order to interrupt the execution.
1547 Ctrl-C is a default. Some system prefers BREAK which is high level of
1548 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1549 Magic SysRq g. It is BREAK signal and character 'g'.
1551 set remote interrupt-on-connect [on | off]
1552 show remote interrupt-on-connect
1553 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1554 remote target when gdb connects to it. This is needed when you debug
1557 set remotebreak [on | off]
1559 Deprecated. Use "set/show remote interrupt-sequence" instead.
1561 tvariable $NAME [ = EXP ]
1562 Create or modify a trace state variable.
1565 List trace state variables and their values.
1567 delete tvariable $NAME ...
1568 Delete one or more trace state variables.
1571 Evaluate the given expressions without collecting anything into the
1572 trace buffer. (Valid in tracepoint actions only.)
1574 ftrace FN / FILE:LINE / *ADDR
1575 Define a fast tracepoint at the given function, line, or address.
1577 * New expression syntax
1579 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1580 GDB now parses 0b101010 identically with 42.
1584 set follow-exec-mode new|same
1585 show follow-exec-mode
1586 Control whether GDB reuses the same inferior across an exec call or
1587 creates a new one. This is useful to be able to restart the old
1588 executable after the inferior having done an exec call.
1590 set default-collect EXPR, ...
1591 show default-collect
1592 Define a list of expressions to be collected at each tracepoint.
1593 This is a useful way to ensure essential items are not overlooked,
1594 such as registers or a critical global variable.
1596 set disconnected-tracing
1597 show disconnected-tracing
1598 If set to 1, the target is instructed to continue tracing if it
1599 loses its connection to GDB. If 0, the target is to stop tracing
1602 set circular-trace-buffer
1603 show circular-trace-buffer
1604 If set to on, the target is instructed to use a circular trace buffer
1605 and discard the oldest trace frames instead of stopping the trace due
1606 to a full trace buffer. If set to off, the trace stops when the buffer
1607 fills up. Some targets may not support this.
1609 set script-extension off|soft|strict
1610 show script-extension
1611 If set to "off", the debugger does not perform any script language
1612 recognition, and all sourced files are assumed to be GDB scripts.
1613 If set to "soft" (the default), files are sourced according to
1614 filename extension, falling back to GDB scripts if the first
1616 If set to "strict", files are sourced according to filename extension.
1618 set ada trust-PAD-over-XVS on|off
1619 show ada trust-PAD-over-XVS
1620 If off, activate a workaround against a bug in the debugging information
1621 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1622 the GCC sources for more information about the GNAT encoding and
1623 PAD types in particular). It is always safe to set this option to
1624 off, but this introduces a slight performance penalty. The default
1627 * Python API Improvements
1629 ** GDB provides the new class gdb.LazyString. This is useful in
1630 some pretty-printing cases. The new method gdb.Value.lazy_string
1631 provides a simple way to create objects of this type.
1633 ** The fields returned by gdb.Type.fields now have an
1634 `is_base_class' attribute.
1636 ** The new method gdb.Type.range returns the range of an array type.
1638 ** The new method gdb.parse_and_eval can be used to parse and
1639 evaluate an expression.
1641 * New remote packets
1644 Define a trace state variable.
1647 Get the current value of a trace state variable.
1650 Set desired tracing behavior upon disconnection.
1653 Set the trace buffer to be linear or circular.
1656 Get data about the tracepoints currently in use.
1660 Process record now works correctly with hardware watchpoints.
1662 Multiple bug fixes have been made to the mips-irix port, making it
1663 much more reliable. In particular:
1664 - Debugging threaded applications is now possible again. Previously,
1665 GDB would hang while starting the program, or while waiting for
1666 the program to stop at a breakpoint.
1667 - Attaching to a running process no longer hangs.
1668 - An error occurring while loading a core file has been fixed.
1669 - Changing the value of the PC register now works again. This fixes
1670 problems observed when using the "jump" command, or when calling
1671 a function from GDB, or even when assigning a new value to $pc.
1672 - With the "finish" and "return" commands, the return value for functions
1673 returning a small array is now correctly printed.
1674 - It is now possible to break on shared library code which gets executed
1675 during a shared library init phase (code executed while executing
1676 their .init section). Previously, the breakpoint would have no effect.
1677 - GDB is now able to backtrace through the signal handler for
1678 non-threaded programs.
1680 PIE (Position Independent Executable) programs debugging is now supported.
1681 This includes debugging execution of PIC (Position Independent Code) shared
1682 libraries although for that, it should be possible to run such libraries as an
1685 *** Changes in GDB 7.0
1687 * GDB now has an interface for JIT compilation. Applications that
1688 dynamically generate code can create symbol files in memory and register
1689 them with GDB. For users, the feature should work transparently, and
1690 for JIT developers, the interface is documented in the GDB manual in the
1691 "JIT Compilation Interface" chapter.
1693 * Tracepoints may now be conditional. The syntax is as for
1694 breakpoints; either an "if" clause appended to the "trace" command,
1695 or the "condition" command is available. GDB sends the condition to
1696 the target for evaluation using the same bytecode format as is used
1697 for tracepoint actions.
1699 * The disassemble command now supports: an optional /r modifier, print the
1700 raw instructions in hex as well as in symbolic form, and an optional /m
1701 modifier to print mixed source+assembly.
1703 * Process record and replay
1705 In a architecture environment that supports ``process record and
1706 replay'', ``process record and replay'' target can record a log of
1707 the process execution, and replay it with both forward and reverse
1710 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1711 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1712 set execution-direction {forward|reverse}, for targets that support
1715 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1716 feature is available with a native GDB running on kernel version
1719 * GDB now has support for multi-byte and wide character sets on the
1720 target. Strings whose character type is wchar_t, char16_t, or
1721 char32_t are now correctly printed. GDB supports wide- and unicode-
1722 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1723 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1724 `printf'. This feature requires iconv to work properly; if your
1725 system does not have a working iconv, GDB can use GNU libiconv. See
1726 the installation instructions for more information.
1728 * GDB now supports automatic retrieval of shared library files from
1729 remote targets. To use this feature, specify a system root that begins
1730 with the `remote:' prefix, either via the `set sysroot' command or via
1731 the `--with-sysroot' configure-time option.
1733 * "info sharedlibrary" now takes an optional regex of libraries to show,
1734 and it now reports if a shared library has no debugging information.
1736 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1737 now complete on file names.
1739 * When completing in expressions, gdb will attempt to limit
1740 completions to allowable structure or union fields, where appropriate.
1741 For instance, consider:
1743 # struct example { int f1; double f2; };
1744 # struct example variable;
1747 If the user types TAB at the end of this command line, the available
1748 completions will be "f1" and "f2".
1750 * Inlined functions are now supported. They show up in backtraces, and
1751 the "step", "next", and "finish" commands handle them automatically.
1753 * GDB now supports the token-splicing (##) and stringification (#)
1754 operators when expanding macros. It also supports variable-arity
1757 * GDB now supports inspecting extra signal information, exported by
1758 the new $_siginfo convenience variable. The feature is currently
1759 implemented on linux ARM, i386 and amd64.
1761 * GDB can now display the VFP floating point registers and NEON vector
1762 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1763 can provide these registers (requires Linux 2.6.30 or later). Remote
1764 and simulator targets may also provide them.
1766 * New remote packets
1769 Search memory for a sequence of bytes.
1772 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1773 operation over reliable transport links. Use of this packet is
1774 controlled by the `set remote noack-packet' command.
1777 Kill the process with the specified process ID. Use this in preference
1778 to `k' when multiprocess protocol extensions are supported.
1781 Obtains additional operating system information
1785 Read or write additional signal information.
1787 * Removed remote protocol undocumented extension
1789 An undocumented extension to the remote protocol's `S' stop reply
1790 packet that permited the stub to pass a process id was removed.
1791 Remote servers should use the `T' stop reply packet instead.
1793 * GDB now supports multiple function calling conventions according to the
1794 DWARF-2 DW_AT_calling_convention function attribute.
1796 * The SH target utilizes the aforementioned change to distinguish between gcc
1797 and Renesas calling convention. It also adds the new CLI commands
1798 `set/show sh calling-convention'.
1800 * GDB can now read compressed debug sections, as produced by GNU gold
1801 with the --compress-debug-sections=zlib flag.
1803 * 64-bit core files are now supported on AIX.
1805 * Thread switching is now supported on Tru64.
1807 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1808 which will be allocated using malloc later in program execution.
1810 * The qXfer:libraries:read remote procotol packet now allows passing a
1811 list of section offsets.
1813 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1814 conditions handling signals delivered during attach or thread creation
1815 have also been fixed.
1817 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1818 From the user's standpoint, all unqualified instances of True and False
1819 are treated as the standard definitions, regardless of context.
1821 * GDB now parses C++ symbol and type names more flexibly. For
1824 template<typename T> class C { };
1827 GDB will now correctly handle all of:
1829 ptype C<char const *>
1830 ptype C<char const*>
1831 ptype C<const char *>
1832 ptype C<const char*>
1834 * New features in the GDB remote stub, gdbserver
1836 - The "--wrapper" command-line argument tells gdbserver to use a
1837 wrapper program to launch programs for debugging.
1839 - On PowerPC and S/390 targets, it is now possible to use a single
1840 gdbserver executable to debug both 32-bit and 64-bit programs.
1841 (This requires gdbserver itself to be built as a 64-bit executable.)
1843 - gdbserver uses the new noack protocol mode for TCP connections to
1844 reduce communications latency, if also supported and enabled in GDB.
1846 - Support for the sparc64-linux-gnu target is now included in
1849 - The amd64-linux build of gdbserver now supports debugging both
1850 32-bit and 64-bit programs.
1852 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1853 now support hardware watchpoints, and will use them automatically
1858 GDB now has support for scripting using Python. Whether this is
1859 available is determined at configure time.
1861 New GDB commands can now be written in Python.
1863 * Ada tasking support
1865 Ada tasks can now be inspected in GDB. The following commands have
1869 Print the list of Ada tasks.
1871 Print detailed information about task number N.
1873 Print the task number of the current task.
1875 Switch the context of debugging to task number N.
1877 * Support for user-defined prefixed commands. The "define" command can
1878 add new commands to existing prefixes, e.g. "target".
1880 * Multi-inferior, multi-process debugging.
1882 GDB now has generalized support for multi-inferior debugging. See
1883 "Debugging Multiple Inferiors" in the manual for more information.
1884 Although availability still depends on target support, the command
1885 set is more uniform now. The GNU/Linux specific multi-forks support
1886 has been migrated to this new framework. This implied some user
1887 visible changes; see "New commands" and also "Removed commands"
1890 * Target descriptions can now describe the target OS ABI. See the
1891 "Target Description Format" section in the user manual for more
1894 * Target descriptions can now describe "compatible" architectures
1895 to indicate that the target can execute applications for a different
1896 architecture in addition to those for the main target architecture.
1897 See the "Target Description Format" section in the user manual for
1900 * Multi-architecture debugging.
1902 GDB now includes general supports for debugging applications on
1903 hybrid systems that use more than one single processor architecture
1904 at the same time. Each such hybrid architecture still requires
1905 specific support to be added. The only hybrid architecture supported
1906 in this version of GDB is the Cell Broadband Engine.
1908 * GDB now supports integrated debugging of Cell/B.E. applications that
1909 use both the PPU and SPU architectures. To enable support for hybrid
1910 Cell/B.E. debugging, you need to configure GDB to support both the
1911 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1912 --enable-targets configure option.
1914 * Non-stop mode debugging.
1916 For some targets, GDB now supports an optional mode of operation in
1917 which you can examine stopped threads while other threads continue
1918 to execute freely. This is referred to as non-stop mode, with the
1919 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1920 section in the user manual for more information.
1922 To be able to support remote non-stop debugging, a remote stub needs
1923 to implement the non-stop mode remote protocol extensions, as
1924 described in the "Remote Non-Stop" section of the user manual. The
1925 GDB remote stub, gdbserver, has been adjusted to support these
1926 extensions on linux targets.
1928 * New commands (for set/show, see "New options" below)
1930 catch syscall [NAME(S) | NUMBER(S)]
1931 Catch system calls. Arguments, which should be names of system
1932 calls or their numbers, mean catch only those syscalls. Without
1933 arguments, every syscall will be caught. When the inferior issues
1934 any of the specified syscalls, GDB will stop and announce the system
1935 call, both when it is called and when its call returns. This
1936 feature is currently available with a native GDB running on the
1937 Linux Kernel, under the following architectures: x86, x86_64,
1938 PowerPC and PowerPC64.
1940 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1942 Search memory for a sequence of bytes.
1944 maint set python print-stack
1945 maint show python print-stack
1946 Show a stack trace when an error is encountered in a Python script.
1949 Invoke CODE by passing it to the Python interpreter.
1954 These allow macros to be defined, undefined, and listed
1958 Show operating system information about processes.
1961 List the inferiors currently under GDB's control.
1964 Switch focus to inferior number NUM.
1967 Detach from inferior number NUM.
1970 Kill inferior number NUM.
1974 set spu stop-on-load
1975 show spu stop-on-load
1976 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1978 set spu auto-flush-cache
1979 show spu auto-flush-cache
1980 Control whether to automatically flush the software-managed cache
1981 during Cell/B.E. debugging.
1983 set sh calling-convention
1984 show sh calling-convention
1985 Control the calling convention used when calling SH target functions.
1988 show debug timestamp
1989 Control display of timestamps with GDB debugging output.
1991 set disassemble-next-line
1992 show disassemble-next-line
1993 Control display of disassembled source lines or instructions when
1996 set remote noack-packet
1997 show remote noack-packet
1998 Set/show the use of remote protocol QStartNoAckMode packet. See above
1999 under "New remote packets."
2001 set remote query-attached-packet
2002 show remote query-attached-packet
2003 Control use of remote protocol `qAttached' (query-attached) packet.
2005 set remote read-siginfo-object
2006 show remote read-siginfo-object
2007 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2010 set remote write-siginfo-object
2011 show remote write-siginfo-object
2012 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2015 set remote reverse-continue
2016 show remote reverse-continue
2017 Control use of remote protocol 'bc' (reverse-continue) packet.
2019 set remote reverse-step
2020 show remote reverse-step
2021 Control use of remote protocol 'bs' (reverse-step) packet.
2023 set displaced-stepping
2024 show displaced-stepping
2025 Control displaced stepping mode. Displaced stepping is a way to
2026 single-step over breakpoints without removing them from the debuggee.
2027 Also known as "out-of-line single-stepping".
2030 show debug displaced
2031 Control display of debugging info for displaced stepping.
2033 maint set internal-error
2034 maint show internal-error
2035 Control what GDB does when an internal error is detected.
2037 maint set internal-warning
2038 maint show internal-warning
2039 Control what GDB does when an internal warning is detected.
2044 Use a wrapper program to launch programs for debugging.
2046 set multiple-symbols (all|ask|cancel)
2047 show multiple-symbols
2048 The value of this variable can be changed to adjust the debugger behavior
2049 when an expression or a breakpoint location contains an ambiguous symbol
2050 name (an overloaded function name, for instance).
2052 set breakpoint always-inserted
2053 show breakpoint always-inserted
2054 Keep breakpoints always inserted in the target, as opposed to inserting
2055 them when resuming the target, and removing them when the target stops.
2056 This option can improve debugger performance on slow remote targets.
2058 set arm fallback-mode (arm|thumb|auto)
2059 show arm fallback-mode
2060 set arm force-mode (arm|thumb|auto)
2062 These commands control how ARM GDB determines whether instructions
2063 are ARM or Thumb. The default for both settings is auto, which uses
2064 the current CPSR value for instructions without symbols; previous
2065 versions of GDB behaved as if "set arm fallback-mode arm".
2067 set disable-randomization
2068 show disable-randomization
2069 Standalone programs run with the virtual address space randomization enabled
2070 by default on some platforms. This option keeps the addresses stable across
2071 multiple debugging sessions.
2075 Control whether other threads are stopped or not when some thread hits
2080 Requests that asynchronous execution is enabled in the target, if available.
2081 In this case, it's possible to resume target in the background, and interact
2082 with GDB while the target is running. "show target-async" displays the
2083 current state of asynchronous execution of the target.
2085 set target-wide-charset
2086 show target-wide-charset
2087 The target-wide-charset is the name of the character set that GDB
2088 uses when printing characters whose type is wchar_t.
2090 set tcp auto-retry (on|off)
2092 set tcp connect-timeout
2093 show tcp connect-timeout
2094 These commands allow GDB to retry failed TCP connections to a remote stub
2095 with a specified timeout period; this is useful if the stub is launched
2096 in parallel with GDB but may not be ready to accept connections immediately.
2098 set libthread-db-search-path
2099 show libthread-db-search-path
2100 Control list of directories which GDB will search for appropriate
2103 set schedule-multiple (on|off)
2104 show schedule-multiple
2105 Allow GDB to resume all threads of all processes or only threads of
2106 the current process.
2110 Use more aggressive caching for accesses to the stack. This improves
2111 performance of remote debugging (particularly backtraces) without
2112 affecting correctness.
2114 set interactive-mode (on|off|auto)
2115 show interactive-mode
2116 Control whether GDB runs in interactive mode (on) or not (off).
2117 When in interactive mode, GDB waits for the user to answer all
2118 queries. Otherwise, GDB does not wait and assumes the default
2119 answer. When set to auto (the default), GDB determines which
2120 mode to use based on the stdin settings.
2125 For program forks, this is replaced by the new more generic `info
2126 inferiors' command. To list checkpoints, you can still use the
2127 `info checkpoints' command, which was an alias for the `info forks'
2131 Replaced by the new `inferior' command. To switch between
2132 checkpoints, you can still use the `restart' command, which was an
2133 alias for the `fork' command.
2136 This is removed, since some targets don't have a notion of
2137 processes. To switch between processes, you can still use the
2138 `inferior' command using GDB's own inferior number.
2141 For program forks, this is replaced by the new more generic `kill
2142 inferior' command. To delete a checkpoint, you can still use the
2143 `delete checkpoint' command, which was an alias for the `delete
2147 For program forks, this is replaced by the new more generic `detach
2148 inferior' command. To detach a checkpoint, you can still use the
2149 `detach checkpoint' command, which was an alias for the `detach
2152 * New native configurations
2154 x86/x86_64 Darwin i[34567]86-*-darwin*
2156 x86_64 MinGW x86_64-*-mingw*
2160 Lattice Mico32 lm32-*
2161 x86 DICOS i[34567]86-*-dicos*
2162 x86_64 DICOS x86_64-*-dicos*
2165 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2166 (mingw32ce) debugging.
2172 These commands were actually not implemented on any target.
2174 *** Changes in GDB 6.8
2176 * New native configurations
2178 NetBSD/hppa hppa*-*netbsd*
2179 Xtensa GNU/Linux xtensa*-*-linux*
2183 NetBSD/hppa hppa*-*-netbsd*
2184 Xtensa GNU/Lunux xtensa*-*-linux*
2186 * Change in command line behavior -- corefiles vs. process ids.
2188 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2189 attaching to process NUMBER fails, GDB no longer attempts to open a
2190 core file named NUMBER. Attaching to a program using the -c option
2191 is no longer supported. Instead, use the '-p' or '--pid' options.
2193 * GDB can now be built as a native debugger for debugging Windows x86
2194 (mingw32) Portable Executable (PE) programs.
2196 * Pending breakpoints no longer change their number when their address
2199 * GDB now supports breakpoints with multiple locations,
2200 including breakpoints on C++ constructors, inside C++ templates,
2201 and in inlined functions.
2203 * GDB's ability to debug optimized code has been improved. GDB more
2204 accurately identifies function bodies and lexical blocks that occupy
2205 more than one contiguous range of addresses.
2207 * Target descriptions can now describe registers for PowerPC.
2209 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2210 registers on PowerPC targets.
2212 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2213 targets even when the libthread_db library is not available.
2215 * The GDB remote stub, gdbserver, now supports the new file transfer
2216 commands (remote put, remote get, and remote delete).
2218 * The GDB remote stub, gdbserver, now supports run and attach in
2219 extended-remote mode.
2221 * hppa*64*-*-hpux11* target broken
2222 The debugger is unable to start a program and fails with the following
2223 error: "Error trying to get information about dynamic linker".
2224 The gdb-6.7 release is also affected.
2226 * GDB now supports the --enable-targets= configure option to allow
2227 building a single GDB executable that supports multiple remote
2228 target architectures.
2230 * GDB now supports debugging C and C++ programs which use the
2231 Decimal Floating Point extension. In addition, the PowerPC target
2232 now has a set of pseudo-registers to inspect decimal float values
2233 stored in two consecutive float registers.
2235 * The -break-insert MI command can optionally create pending
2238 * Improved support for debugging Ada
2239 Many improvements to the Ada language support have been made. These
2241 - Better support for Ada2005 interface types
2242 - Improved handling of arrays and slices in general
2243 - Better support for Taft-amendment types
2244 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2246 - Improved command completion in Ada
2249 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2254 set print frame-arguments (all|scalars|none)
2255 show print frame-arguments
2256 The value of this variable can be changed to control which argument
2257 values should be printed by the debugger when displaying a frame.
2262 Transfer files to and from a remote target, and delete remote files.
2269 Transfer files to and from a remote target, and delete remote files.
2271 * New remote packets
2278 Open, close, read, write, and delete files on the remote system.
2281 Attach to an existing process on the remote system, in extended-remote
2285 Run a new process on the remote system, in extended-remote mode.
2287 *** Changes in GDB 6.7
2289 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2290 bfd, libiberty and opcodes, as revealed by static analysis donated by
2291 Coverity, Inc. (http://scan.coverity.com).
2293 * When looking up multiply-defined global symbols, GDB will now prefer the
2294 symbol definition in the current shared library if it was built using the
2295 -Bsymbolic linker option.
2297 * When the Text User Interface (TUI) is not configured, GDB will now
2298 recognize the -tui command-line option and print a message that the TUI
2301 * The GDB remote stub, gdbserver, now has lower overhead for high
2302 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2304 * GDB for MIPS targets now autodetects whether a remote target provides
2305 32-bit or 64-bit register values.
2307 * Support for C++ member pointers has been improved.
2309 * GDB now understands XML target descriptions, which specify the
2310 target's overall architecture. GDB can read a description from
2311 a local file or over the remote serial protocol.
2313 * Vectors of single-byte data use a new integer type which is not
2314 automatically displayed as character or string data.
2316 * The /s format now works with the print command. It displays
2317 arrays of single-byte integers and pointers to single-byte integers
2320 * Target descriptions can now describe target-specific registers,
2321 for architectures which have implemented the support (currently
2322 only ARM, M68K, and MIPS).
2324 * GDB and the GDB remote stub, gdbserver, now support the XScale
2327 * The GDB remote stub, gdbserver, has been updated to support
2328 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2329 has been rewritten to use the standard GDB remote protocol.
2331 * GDB can now step into C++ functions which are called through thunks.
2333 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2335 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2336 layout. It also supports a TextSeg= and DataSeg= response when only
2337 segment base addresses (rather than offsets) are available.
2339 * The /i format now outputs any trailing branch delay slot instructions
2340 immediately following the last instruction within the count specified.
2342 * The GDB remote protocol "T" stop reply packet now supports a
2343 "library" response. Combined with the new "qXfer:libraries:read"
2344 packet, this response allows GDB to debug shared libraries on targets
2345 where the operating system manages the list of loaded libraries (e.g.
2346 Windows and SymbianOS).
2348 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2349 (DLLs) on Windows and Windows CE targets.
2351 * GDB now supports a faster verification that a .debug file matches its binary
2352 according to its build-id signature, if the signature is present.
2358 Enable or disable hardware flow control (RTS/CTS) on the serial port
2359 when debugging using remote targets.
2361 set mem inaccessible-by-default
2362 show mem inaccessible-by-default
2363 If the target supplies a memory map, for instance via the remote
2364 protocol's "qXfer:memory-map:read" packet, setting this variable
2365 prevents GDB from accessing memory outside the memory map. This
2366 is useful for targets with memory mapped registers or which react
2367 badly to accesses of unmapped address space.
2369 set breakpoint auto-hw
2370 show breakpoint auto-hw
2371 If the target supplies a memory map, for instance via the remote
2372 protocol's "qXfer:memory-map:read" packet, setting this variable
2373 lets GDB use hardware breakpoints automatically for memory regions
2374 where it can not use software breakpoints. This covers both the
2375 "break" command and internal breakpoints used for other commands
2376 including "next" and "finish".
2379 catch exception unhandled
2380 Stop the program execution when Ada exceptions are raised.
2383 Stop the program execution when an Ada assertion failed.
2387 Set an alternate system root for target files. This is a more
2388 general version of "set solib-absolute-prefix", which is now
2389 an alias to "set sysroot".
2392 Provide extended SPU facility status information. This set of
2393 commands is available only when debugging the Cell/B.E. SPU
2396 * New native configurations
2398 OpenBSD/sh sh*-*openbsd*
2401 unset tdesc filename
2403 Use the specified local file as an XML target description, and do
2404 not query the target for its built-in description.
2408 OpenBSD/sh sh*-*-openbsd*
2409 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2410 Toshiba Media Processor mep-elf
2412 * New remote packets
2415 Ignore the specified signals; pass them directly to the debugged program
2416 without stopping other threads or reporting them to GDB.
2418 qXfer:features:read:
2419 Read an XML target description from the target, which describes its
2424 Read or write contents of an spufs file on the target system. These
2425 packets are available only on the Cell/B.E. SPU architecture.
2427 qXfer:libraries:read:
2428 Report the loaded shared libraries. Combined with new "T" packet
2429 response, this packet allows GDB to debug shared libraries on
2430 targets where the operating system manages the list of loaded
2431 libraries (e.g. Windows and SymbianOS).
2435 Support for these obsolete configurations has been removed.
2443 i[34567]86-*-lynxos*
2444 i[34567]86-*-netware*
2445 i[34567]86-*-sco3.2v5*
2446 i[34567]86-*-sco3.2v4*
2448 i[34567]86-*-sysv4.2*
2451 i[34567]86-*-unixware2*
2452 i[34567]86-*-unixware*
2461 * Other removed features
2468 Various m68k-only ROM monitors.
2475 Various Renesas ROM monitors and debugging interfaces for SH and
2480 Support for a Macraigor serial interface to on-chip debugging.
2481 GDB does not directly support the newer parallel or USB
2486 A debug information format. The predecessor to DWARF 2 and
2487 DWARF 3, which are still supported.
2489 Support for the HP aCC compiler on HP-UX/PA-RISC
2491 SOM-encapsulated symbolic debugging information, automatic
2492 invocation of pxdb, and the aCC custom C++ ABI. This does not
2493 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2494 with aCC can still be debugged on an assembly level.
2496 MIPS ".pdr" sections
2498 A MIPS-specific format used to describe stack frame layout
2499 in debugging information.
2503 GDB could work with an older version of Guile to debug
2504 the interpreter and Scheme programs running in it.
2506 set mips stack-arg-size
2507 set mips saved-gpreg-size
2509 Use "set mips abi" to control parameter passing for MIPS.
2511 *** Changes in GDB 6.6
2516 Cell Broadband Engine SPU spu-elf
2518 * GDB can now be configured as a cross-debugger targeting native Windows
2519 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2520 running on a Windows system over TCP/IP to debug Windows programs.
2522 * The GDB remote stub, gdbserver, has been updated to support Windows and
2523 Cygwin debugging. Both single-threaded and multi-threaded programs are
2526 * The "set trust-readonly-sections" command works again. This command was
2527 broken in GDB 6.3, 6.4, and 6.5.
2529 * The "load" command now supports writing to flash memory, if the remote
2530 stub provides the required support.
2532 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2533 longer requires symbolic debug information (e.g. DWARF-2).
2538 unset substitute-path
2539 show substitute-path
2540 Manage a list of substitution rules that GDB uses to rewrite the name
2541 of the directories where the sources are located. This can be useful
2542 for instance when the sources were moved to a different location
2543 between compilation and debugging.
2547 Print each CLI command as it is executed. Each command is prefixed with
2548 a number of `+' symbols representing the nesting depth.
2549 The source command now has a `-v' option to enable the same feature.
2553 The ARM Demon monitor support (RDP protocol, "target rdp").
2555 Kernel Object Display, an embedded debugging feature which only worked with
2556 an obsolete version of Cisco IOS.
2558 The 'set download-write-size' and 'show download-write-size' commands.
2560 * New remote packets
2563 Tell a stub about GDB client features, and request remote target features.
2564 The first feature implemented is PacketSize, which allows the target to
2565 specify the size of packets it can handle - to minimize the number of
2566 packets required and improve performance when connected to a remote
2570 Fetch an OS auxilliary vector from the remote stub. This packet is a
2571 more efficient replacement for qPart:auxv:read.
2573 qXfer:memory-map:read:
2574 Fetch a memory map from the remote stub, including information about
2575 RAM, ROM, and flash memory devices.
2580 Erase and program a flash memory device.
2582 * Removed remote packets
2585 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2586 used it, and only gdbserver implemented it.
2588 *** Changes in GDB 6.5
2592 Renesas M32C/M16C m32c-elf
2594 Morpho Technologies ms1 ms1-elf
2598 init-if-undefined Initialize a convenience variable, but
2599 only if it doesn't already have a value.
2601 The following commands are presently only implemented for native GNU/Linux:
2603 checkpoint Save a snapshot of the program state.
2605 restart <n> Return the program state to a
2606 previously saved state.
2608 info checkpoints List currently saved checkpoints.
2610 delete-checkpoint <n> Delete a previously saved checkpoint.
2612 set|show detach-on-fork Tell gdb whether to detach from a newly
2613 forked process, or to keep debugging it.
2615 info forks List forks of the user program that
2616 are available to be debugged.
2618 fork <n> Switch to debugging one of several
2619 forks of the user program that are
2620 available to be debugged.
2622 delete-fork <n> Delete a fork from the list of forks
2623 that are available to be debugged (and
2624 kill the forked process).
2626 detach-fork <n> Delete a fork from the list of forks
2627 that are available to be debugged (and
2628 allow the process to continue).
2632 Morpho Technologies ms2 ms1-elf
2634 * Improved Windows host support
2636 GDB now builds as a cross debugger hosted on i686-mingw32, including
2637 native console support, and remote communications using either
2638 network sockets or serial ports.
2640 * Improved Modula-2 language support
2642 GDB can now print most types in the Modula-2 syntax. This includes:
2643 basic types, set types, record types, enumerated types, range types,
2644 pointer types and ARRAY types. Procedure var parameters are correctly
2645 printed and hexadecimal addresses and character constants are also
2646 written in the Modula-2 syntax. Best results can be obtained by using
2647 GNU Modula-2 together with the -gdwarf-2 command line option.
2651 The ARM rdi-share module.
2653 The Netware NLM debug server.
2655 *** Changes in GDB 6.4
2657 * New native configurations
2659 OpenBSD/arm arm*-*-openbsd*
2660 OpenBSD/mips64 mips64-*-openbsd*
2664 Morpho Technologies ms1 ms1-elf
2666 * New command line options
2668 --batch-silent As for --batch, but totally silent.
2669 --return-child-result The debugger will exist with the same value
2670 the child (debugged) program exited with.
2671 --eval-command COMMAND, -ex COMMAND
2672 Execute a single GDB CLI command. This may be
2673 specified multiple times and in conjunction
2674 with the --command (-x) option.
2676 * Deprecated commands removed
2678 The following commands, that were deprecated in 2000, have been
2682 set|show arm disassembly-flavor set|show arm disassembler
2683 othernames set arm disassembler
2684 set|show remotedebug set|show debug remote
2685 set|show archdebug set|show debug arch
2686 set|show eventdebug set|show debug event
2689 * New BSD user-level threads support
2691 It is now possible to debug programs using the user-level threads
2692 library on OpenBSD and FreeBSD. Currently supported (target)
2695 FreeBSD/amd64 x86_64-*-freebsd*
2696 FreeBSD/i386 i386-*-freebsd*
2697 OpenBSD/i386 i386-*-openbsd*
2699 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2700 are not yet supported.
2702 * New support for Matsushita MN10300 w/sim added
2703 (Work in progress). mn10300-elf.
2705 * REMOVED configurations and files
2707 VxWorks and the XDR protocol *-*-vxworks
2708 Motorola MCORE mcore-*-*
2709 National Semiconductor NS32000 ns32k-*-*
2711 * New "set print array-indexes" command
2713 After turning this setting "on", GDB prints the index of each element
2714 when displaying arrays. The default is "off" to preserve the previous
2717 * VAX floating point support
2719 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2721 * User-defined command support
2723 In addition to using $arg0..$arg9 for argument passing, it is now possible
2724 to use $argc to determine now many arguments have been passed. See the
2725 section on user-defined commands in the user manual for more information.
2727 *** Changes in GDB 6.3:
2729 * New command line option
2731 GDB now accepts -l followed by a number to set the timeout for remote
2734 * GDB works with GCC -feliminate-dwarf2-dups
2736 GDB now supports a more compact representation of DWARF-2 debug
2737 information using DW_FORM_ref_addr references. These are produced
2738 by GCC with the option -feliminate-dwarf2-dups and also by some
2739 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2740 to use -feliminate-dwarf2-dups.
2742 * Internationalization
2744 When supported by the host system, GDB will be built with
2745 internationalization (libintl). The task of marking up the sources is
2746 continued, we're looking forward to our first translation.
2750 Initial support for debugging programs compiled with the GNAT
2751 implementation of the Ada programming language has been integrated
2752 into GDB. In this release, support is limited to expression evaluation.
2754 * New native configurations
2756 GNU/Linux/m32r m32r-*-linux-gnu
2760 GDB's remote protocol now includes support for the 'p' packet. This
2761 packet is used to fetch individual registers from a remote inferior.
2763 * END-OF-LIFE registers[] compatibility module
2765 GDB's internal register infrastructure has been completely rewritten.
2766 The new infrastructure making possible the implementation of key new
2767 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2770 GDB 6.3 will be the last release to include the the registers[]
2771 compatibility module that allowed out-of-date configurations to
2772 continue to work. This change directly impacts the following
2782 powerpc bdm protocol
2784 Unless there is activity to revive these configurations, they will be
2785 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2787 * OBSOLETE configurations and files
2789 Configurations that have been declared obsolete in this release have
2790 been commented out. Unless there is activity to revive these
2791 configurations, the next release of GDB will have their sources
2792 permanently REMOVED.
2801 *** Changes in GDB 6.2.1:
2803 * MIPS `break main; run' gave an heuristic-fence-post warning
2805 When attempting to run even a simple program, a warning about
2806 heuristic-fence-post being hit would be reported. This problem has
2809 * MIPS IRIX 'long double' crashed GDB
2811 When examining a long double variable, GDB would get a segmentation
2812 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2813 IRIX long double values).
2817 A bug in the VAX stack code was causing problems with the "next"
2818 command. This problem has been fixed.
2820 *** Changes in GDB 6.2:
2822 * Fix for ``many threads''
2824 On GNU/Linux systems that use the NPTL threads library, a program
2825 rapidly creating and deleting threads would confuse GDB leading to the
2828 ptrace: No such process.
2829 thread_db_get_info: cannot get thread info: generic error
2831 This problem has been fixed.
2833 * "-async" and "-noasync" options removed.
2835 Support for the broken "-noasync" option has been removed (it caused
2838 * New ``start'' command.
2840 This command runs the program until the begining of the main procedure.
2842 * New BSD Kernel Data Access Library (libkvm) interface
2844 Using ``target kvm'' it is now possible to debug kernel core dumps and
2845 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2846 platforms. Currently supported (native-only) configurations are:
2848 FreeBSD/amd64 x86_64-*-freebsd*
2849 FreeBSD/i386 i?86-*-freebsd*
2850 NetBSD/i386 i?86-*-netbsd*
2851 NetBSD/m68k m68*-*-netbsd*
2852 NetBSD/sparc sparc-*-netbsd*
2853 OpenBSD/amd64 x86_64-*-openbsd*
2854 OpenBSD/i386 i?86-*-openbsd*
2855 OpenBSD/m68k m68*-openbsd*
2856 OpenBSD/sparc sparc-*-openbsd*
2858 * Signal trampoline code overhauled
2860 Many generic problems with GDB's signal handling code have been fixed.
2861 These include: backtraces through non-contiguous stacks; recognition
2862 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2863 call; backtrace through a signal trampoline; step into and out of
2864 signal handlers; and single-stepping in the signal trampoline.
2866 Please note that kernel bugs are a limiting factor here. These
2867 features have been shown to work on an s390 GNU/Linux system that
2868 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2870 * Cygwin support for DWARF 2 added.
2872 * New native configurations
2874 GNU/Linux/hppa hppa*-*-linux*
2875 OpenBSD/hppa hppa*-*-openbsd*
2876 OpenBSD/m68k m68*-*-openbsd*
2877 OpenBSD/m88k m88*-*-openbsd*
2878 OpenBSD/powerpc powerpc-*-openbsd*
2879 NetBSD/vax vax-*-netbsd*
2880 OpenBSD/vax vax-*-openbsd*
2882 * END-OF-LIFE frame compatibility module
2884 GDB's internal frame infrastructure has been completely rewritten.
2885 The new infrastructure making it possible to support key new features
2886 including DWARF 2 Call Frame Information. To aid in the task of
2887 migrating old configurations to this new infrastructure, a
2888 compatibility module, that allowed old configurations to continue to
2889 work, was also included.
2891 GDB 6.2 will be the last release to include this frame compatibility
2892 module. This change directly impacts the following configurations:
2902 Unless there is activity to revive these configurations, they will be
2903 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2905 * REMOVED configurations and files
2907 Sun 3, running SunOS 3 m68*-*-sunos3*
2908 Sun 3, running SunOS 4 m68*-*-sunos4*
2909 Sun 2, running SunOS 3 m68000-*-sunos3*
2910 Sun 2, running SunOS 4 m68000-*-sunos4*
2911 Motorola 680x0 running LynxOS m68*-*-lynxos*
2912 AT&T 3b1/Unix pc m68*-att-*
2913 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2914 decstation mips-dec-* mips-little-*
2915 riscos mips-*-riscos* mips-*-sysv*
2916 sonymips mips-sony-*
2917 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2919 *** Changes in GDB 6.1.1:
2921 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2923 The TUI (Text-mode User Interface) is now built as part of a default
2924 GDB configuration. It is enabled by either selecting the TUI with the
2925 command line option "-i=tui" or by running the separate "gdbtui"
2926 program. For more information on the TUI, see the manual "Debugging
2929 * Pending breakpoint support (also included in GDB 6.1)
2931 Support has been added to allow you to specify breakpoints in shared
2932 libraries that have not yet been loaded. If a breakpoint location
2933 cannot be found, and the "breakpoint pending" option is set to auto,
2934 GDB queries you if you wish to make the breakpoint pending on a future
2935 shared-library load. If and when GDB resolves the breakpoint symbol,
2936 the pending breakpoint is removed as one or more regular breakpoints
2939 Pending breakpoints are very useful for GCJ Java debugging.
2941 * Fixed ISO-C build problems
2943 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2944 non ISO-C code that stopped them being built using a more strict ISO-C
2945 compiler (e.g., IBM's C compiler).
2947 * Fixed build problem on IRIX 5
2949 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2950 wasn't able to compile compile on an IRIX 5 system.
2952 * Added execute permission to gdb/gdbserver/configure
2954 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2955 permission. This bug would cause configure to fail on a number of
2956 systems (Solaris, IRIX). Ref: server/519.
2958 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2960 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2961 has been updated to use constant array sizes.
2963 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2965 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2966 its generated DWARF Call Frame Info. This encoding was causing GDB to
2967 panic, that panic has been fixed. Ref: gdb/1628.
2969 * Fixed a problem when examining parameters in shared library code.
2971 When examining parameters in optimized shared library code generated
2972 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2973 not available''. GDB now correctly displays the variable's value.
2975 *** Changes in GDB 6.1:
2977 * Removed --with-mmalloc
2979 Support for the mmalloc memory manager has been removed, as it
2980 conflicted with the internal gdb byte cache.
2982 * Changes in AMD64 configurations
2984 The AMD64 target now includes the %cs and %ss registers. As a result
2985 the AMD64 remote protocol has changed; this affects the floating-point
2986 and SSE registers. If you rely on those registers for your debugging,
2987 you should upgrade gdbserver on the remote side.
2989 * Revised SPARC target
2991 The SPARC target has been completely revised, incorporating the
2992 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2993 support for LynxOS and SunOS 4 has been dropped. Calling functions
2994 from within GDB on operating systems with a non-executable stack
2995 (Solaris, OpenBSD) now works.
2999 GDB has a new C++ demangler which does a better job on the mangled
3000 names generated by current versions of g++. It also runs faster, so
3001 with this and other changes gdb should now start faster on large C++
3004 * DWARF 2 Location Expressions
3006 GDB support for location expressions has been extended to support function
3007 arguments and frame bases. Older versions of GDB could crash when they
3010 * C++ nested types and namespaces
3012 GDB's support for nested types and namespaces in C++ has been
3013 improved, especially if you use the DWARF 2 debugging format. (This
3014 is the default for recent versions of GCC on most platforms.)
3015 Specifically, if you have a class "Inner" defined within a class or
3016 namespace "Outer", then GDB realizes that the class's name is
3017 "Outer::Inner", not simply "Inner". This should greatly reduce the
3018 frequency of complaints about not finding RTTI symbols. In addition,
3019 if you are stopped at inside of a function defined within a namespace,
3020 GDB modifies its name lookup accordingly.
3022 * New native configurations
3024 NetBSD/amd64 x86_64-*-netbsd*
3025 OpenBSD/amd64 x86_64-*-openbsd*
3026 OpenBSD/alpha alpha*-*-openbsd*
3027 OpenBSD/sparc sparc-*-openbsd*
3028 OpenBSD/sparc64 sparc64-*-openbsd*
3030 * New debugging protocols
3032 M32R with SDI protocol m32r-*-elf*
3034 * "set prompt-escape-char" command deleted.
3036 The command "set prompt-escape-char" has been deleted. This command,
3037 and its very obscure effet on GDB's prompt, was never documented,
3038 tested, nor mentioned in the NEWS file.
3040 * OBSOLETE configurations and files
3042 Configurations that have been declared obsolete in this release have
3043 been commented out. Unless there is activity to revive these
3044 configurations, the next release of GDB will have their sources
3045 permanently REMOVED.
3047 Sun 3, running SunOS 3 m68*-*-sunos3*
3048 Sun 3, running SunOS 4 m68*-*-sunos4*
3049 Sun 2, running SunOS 3 m68000-*-sunos3*
3050 Sun 2, running SunOS 4 m68000-*-sunos4*
3051 Motorola 680x0 running LynxOS m68*-*-lynxos*
3052 AT&T 3b1/Unix pc m68*-att-*
3053 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3054 decstation mips-dec-* mips-little-*
3055 riscos mips-*-riscos* mips-*-sysv*
3056 sonymips mips-sony-*
3057 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3059 * REMOVED configurations and files
3061 SGI Irix-4.x mips-sgi-irix4 or iris4
3062 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3063 Z8000 simulator z8k-zilog-none or z8ksim
3064 Matsushita MN10200 w/simulator mn10200-*-*
3065 H8/500 simulator h8500-hitachi-hms or h8500hms
3066 HP/PA running BSD hppa*-*-bsd*
3067 HP/PA running OSF/1 hppa*-*-osf*
3068 HP/PA Pro target hppa*-*-pro*
3069 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3070 386BSD i[3456]86-*-bsd*
3071 Sequent family i[3456]86-sequent-sysv4*
3072 i[3456]86-sequent-sysv*
3073 i[3456]86-sequent-bsd*
3074 SPARC running LynxOS sparc-*-lynxos*
3075 SPARC running SunOS 4 sparc-*-sunos4*
3076 Tsqware Sparclet sparclet-*-*
3077 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3079 *** Changes in GDB 6.0:
3083 Support for debugging the Objective-C programming language has been
3084 integrated into GDB.
3086 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3088 DWARF 2's Call Frame Information makes available compiler generated
3089 information that more exactly describes the program's run-time stack.
3090 By using this information, GDB is able to provide more robust stack
3093 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3094 have been updated to use a new backtrace mechanism which includes
3095 DWARF 2 CFI support.
3099 GDB's remote protocol has been extended to include support for hosted
3100 file I/O (where the remote target uses GDB's file system). See GDB's
3101 remote protocol documentation for details.
3103 * All targets using the new architecture framework.
3105 All of GDB's targets have been updated to use the new internal
3106 architecture framework. The way is now open for future GDB releases
3107 to include cross-architecture native debugging support (i386 on amd64,
3110 * GNU/Linux's Thread Local Storage (TLS)
3112 GDB now includes support for for the GNU/Linux implementation of
3113 per-thread variables.
3115 * GNU/Linux's Native POSIX Thread Library (NPTL)
3117 GDB's thread code has been updated to work with either the new
3118 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3120 * Separate debug info.
3122 GDB, in conjunction with BINUTILS, now supports a mechanism for
3123 automatically loading debug information from a separate file. Instead
3124 of shipping full debug and non-debug versions of system libraries,
3125 system integrators can now instead ship just the stripped libraries
3126 and optional debug files.
3128 * DWARF 2 Location Expressions
3130 DWARF 2 Location Expressions allow the compiler to more completely
3131 describe the location of variables (even in optimized code) to the
3134 GDB now includes preliminary support for location expressions (support
3135 for DW_OP_piece is still missing).
3139 A number of long standing bugs that caused GDB to die while starting a
3140 Java application have been fixed. GDB's Java support is now
3141 considered "useable".
3143 * GNU/Linux support for fork, vfork, and exec.
3145 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3146 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3149 * GDB supports logging output to a file
3151 There are two new commands, "set logging" and "show logging", which can be
3152 used to capture GDB's output to a file.
3154 * The meaning of "detach" has changed for gdbserver
3156 The "detach" command will now resume the application, as documented. To
3157 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3160 * d10v, m68hc11 `regs' command deprecated
3162 The `info registers' command has been updated so that it displays the
3163 registers using a format identical to the old `regs' command.
3167 A new command, "maint set profile on/off", has been added. This command can
3168 be used to enable or disable profiling while running GDB, to profile a
3169 session or a set of commands. In addition there is a new configure switch,
3170 "--enable-profiling", which will cause GDB to be compiled with profiling
3171 data, for more informative profiling results.
3173 * Default MI syntax changed to "mi2".
3175 The default MI (machine interface) syntax, enabled by the command line
3176 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3177 "mi1", can be enabled by specifying the option "-i=mi1".
3179 Support for the original "mi0" syntax (included in GDB 5.0) has been
3182 Fix for gdb/192: removed extraneous space when displaying frame level.
3183 Fix for gdb/672: update changelist is now output in mi list format.
3184 Fix for gdb/702: a -var-assign that updates the value now shows up
3185 in a subsequent -var-update.
3187 * New native configurations.
3189 FreeBSD/amd64 x86_64-*-freebsd*
3191 * Multi-arched targets.
3193 HP/PA HPUX11 hppa*-*-hpux*
3194 Renesas M32R/D w/simulator m32r-*-elf*
3196 * OBSOLETE configurations and files
3198 Configurations that have been declared obsolete in this release have
3199 been commented out. Unless there is activity to revive these
3200 configurations, the next release of GDB will have their sources
3201 permanently REMOVED.
3203 Z8000 simulator z8k-zilog-none or z8ksim
3204 Matsushita MN10200 w/simulator mn10200-*-*
3205 H8/500 simulator h8500-hitachi-hms or h8500hms
3206 HP/PA running BSD hppa*-*-bsd*
3207 HP/PA running OSF/1 hppa*-*-osf*
3208 HP/PA Pro target hppa*-*-pro*
3209 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3210 Sequent family i[3456]86-sequent-sysv4*
3211 i[3456]86-sequent-sysv*
3212 i[3456]86-sequent-bsd*
3213 Tsqware Sparclet sparclet-*-*
3214 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3216 * REMOVED configurations and files
3219 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3220 IBM AIX PS/2 i[3456]86-*-aix
3221 i386 running Mach 3.0 i[3456]86-*-mach3*
3222 i386 running Mach i[3456]86-*-mach*
3223 i386 running OSF/1 i[3456]86-*osf1mk*
3224 HP/Apollo 68k Family m68*-apollo*-sysv*,
3226 m68*-hp-bsd*, m68*-hp-hpux*
3227 Argonaut Risc Chip (ARC) arc-*-*
3228 Mitsubishi D30V d30v-*-*
3229 Fujitsu FR30 fr30-*-elf*
3230 OS/9000 i[34]86-*-os9k
3231 I960 with MON960 i960-*-coff
3233 * MIPS $fp behavior changed
3235 The convenience variable $fp, for the MIPS, now consistently returns
3236 the address of the current frame's base. Previously, depending on the
3237 context, $fp could refer to either $sp or the current frame's base
3238 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3239 The GNU Source-Level Debugger''.
3241 *** Changes in GDB 5.3:
3243 * GNU/Linux shared library multi-threaded performance improved.
3245 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3246 `/proc', in preference to `ptrace' for memory reads. This may result
3247 in an improvement in the start-up time of multi-threaded, shared
3248 library applications when run under GDB. One GDB user writes: ``loads
3249 shared libs like mad''.
3251 * ``gdbserver'' now supports multi-threaded applications on some targets
3253 Support for debugging multi-threaded applications which use
3254 the GNU/Linux LinuxThreads package has been added for
3255 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3256 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3258 * GDB now supports C/C++ preprocessor macros.
3260 GDB now expands preprocessor macro invocations in C/C++ expressions,
3261 and provides various commands for showing macro definitions and how
3264 The new command `macro expand EXPRESSION' expands any macro
3265 invocations in expression, and shows the result.
3267 The new command `show macro MACRO-NAME' shows the definition of the
3268 macro named MACRO-NAME, and where it was defined.
3270 Most compilers don't include information about macros in the debugging
3271 information by default. In GCC 3.1, for example, you need to compile
3272 your program with the options `-gdwarf-2 -g3'. If the macro
3273 information is present in the executable, GDB will read it.
3275 * Multi-arched targets.
3277 DEC Alpha (partial) alpha*-*-*
3278 DEC VAX (partial) vax-*-*
3280 National Semiconductor NS32000 (partial) ns32k-*-*
3281 Motorola 68000 (partial) m68k-*-*
3282 Motorola MCORE mcore-*-*
3286 Fujitsu FRV architecture added by Red Hat frv*-*-*
3289 * New native configurations
3291 Alpha NetBSD alpha*-*-netbsd*
3292 SH NetBSD sh*-*-netbsdelf*
3293 MIPS NetBSD mips*-*-netbsd*
3294 UltraSPARC NetBSD sparc64-*-netbsd*
3296 * OBSOLETE configurations and files
3298 Configurations that have been declared obsolete in this release have
3299 been commented out. Unless there is activity to revive these
3300 configurations, the next release of GDB will have their sources
3301 permanently REMOVED.
3303 Mitsubishi D30V d30v-*-*
3304 OS/9000 i[34]86-*-os9k
3305 IBM AIX PS/2 i[3456]86-*-aix
3306 Fujitsu FR30 fr30-*-elf*
3307 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3308 Argonaut Risc Chip (ARC) arc-*-*
3309 i386 running Mach 3.0 i[3456]86-*-mach3*
3310 i386 running Mach i[3456]86-*-mach*
3311 i386 running OSF/1 i[3456]86-*osf1mk*
3312 HP/Apollo 68k Family m68*-apollo*-sysv*,
3314 m68*-hp-bsd*, m68*-hp-hpux*
3315 I960 with MON960 i960-*-coff
3317 * OBSOLETE languages
3319 CHILL, a Pascal like language used by telecommunications companies.
3321 * REMOVED configurations and files
3323 AMD 29k family via UDI a29k-amd-udi, udi29k
3324 A29K VxWorks a29k-*-vxworks
3325 AMD 29000 embedded, using EBMON a29k-none-none
3326 AMD 29000 embedded with COFF a29k-none-coff
3327 AMD 29000 embedded with a.out a29k-none-aout
3329 testsuite/gdb.hp/gdb.threads-hp/ directory
3331 * New command "set max-user-call-depth <nnn>"
3333 This command allows the user to limit the call depth of user-defined
3334 commands. The default is 1024.
3336 * Changes in FreeBSD/i386 native debugging.
3338 Support for the "generate-core-file" has been added.
3340 * New commands "dump", "append", and "restore".
3342 These commands allow data to be copied from target memory
3343 to a bfd-format or binary file (dump and append), and back
3344 from a file into memory (restore).
3346 * Improved "next/step" support on multi-processor Alpha Tru64.
3348 The previous single-step mechanism could cause unpredictable problems,
3349 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3350 of a software single-step mechanism prevents this.
3352 *** Changes in GDB 5.2.1:
3360 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3361 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3362 Fix, by Joel Brobecker imported from mainline.
3364 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3365 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3366 Fix, by Fred Fish, imported from mainline.
3368 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3369 Surprisingly enough, it works now.
3370 By Michal Ludvig, imported from mainline.
3372 i386 hardware watchpoint support:
3373 avoid misses on second run for some targets.
3374 By Pierre Muller, imported from mainline.
3376 *** Changes in GDB 5.2:
3378 * New command "set trust-readonly-sections on[off]".
3380 This command is a hint that tells gdb that read-only sections
3381 really are read-only (ie. that their contents will not change).
3382 In this mode, gdb will go to the object file rather than the
3383 target to read memory from read-only sections (such as ".text").
3384 This can be a significant performance improvement on some
3385 (notably embedded) targets.
3387 * New command "generate-core-file" (or "gcore").
3389 This new gdb command allows the user to drop a core file of the child
3390 process state at any time. So far it's been implemented only for
3391 GNU/Linux and Solaris, but should be relatively easily ported to other
3392 hosts. Argument is core file name (defaults to core.<pid>).
3394 * New command line option
3396 GDB now accepts --pid or -p followed by a process id.
3398 * Change in command line behavior -- corefiles vs. process ids.
3400 There is a subtle behavior in the way in which GDB handles
3401 command line arguments. The first non-flag argument is always
3402 a program to debug, but the second non-flag argument may either
3403 be a corefile or a process id. Previously, GDB would attempt to
3404 open the second argument as a corefile, and if that failed, would
3405 issue a superfluous error message and then attempt to attach it as
3406 a process. Now, if the second argument begins with a non-digit,
3407 it will be treated as a corefile. If it begins with a digit,
3408 GDB will attempt to attach it as a process, and if no such process
3409 is found, will then attempt to open it as a corefile.
3411 * Changes in ARM configurations.
3413 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3414 configuration is fully multi-arch.
3416 * New native configurations
3418 ARM NetBSD arm*-*-netbsd*
3419 x86 OpenBSD i[3456]86-*-openbsd*
3420 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3421 Sparc64 running FreeBSD sparc64-*-freebsd*
3425 Sanyo XStormy16 xstormy16-elf
3427 * OBSOLETE configurations and files
3429 Configurations that have been declared obsolete in this release have
3430 been commented out. Unless there is activity to revive these
3431 configurations, the next release of GDB will have their sources
3432 permanently REMOVED.
3434 AMD 29k family via UDI a29k-amd-udi, udi29k
3435 A29K VxWorks a29k-*-vxworks
3436 AMD 29000 embedded, using EBMON a29k-none-none
3437 AMD 29000 embedded with COFF a29k-none-coff
3438 AMD 29000 embedded with a.out a29k-none-aout
3440 testsuite/gdb.hp/gdb.threads-hp/ directory
3442 * REMOVED configurations and files
3444 TI TMS320C80 tic80-*-*
3446 PowerPC Solaris powerpcle-*-solaris*
3447 PowerPC Windows NT powerpcle-*-cygwin32
3448 PowerPC Netware powerpc-*-netware*
3449 Harris/CXUX m88k m88*-harris-cxux*
3450 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3451 ns32k-utek-sysv* ns32k-utek-*
3452 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3453 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3454 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3455 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3456 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3458 * Changes to command line processing
3460 The new `--args' feature can be used to specify command-line arguments
3461 for the inferior from gdb's command line.
3463 * Changes to key bindings
3465 There is a new `operate-and-get-next' function bound to `C-o'.
3467 *** Changes in GDB 5.1.1
3469 Fix compile problem on DJGPP.
3471 Fix a problem with floating-point registers on the i386 being
3474 Fix to stop GDB crashing on .debug_str debug info.
3476 Numerous documentation fixes.
3478 Numerous testsuite fixes.
3480 *** Changes in GDB 5.1:
3482 * New native configurations
3484 Alpha FreeBSD alpha*-*-freebsd*
3485 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3486 MIPS GNU/Linux mips*-*-linux*
3487 MIPS SGI Irix 6.x mips*-sgi-irix6*
3488 ia64 AIX ia64-*-aix*
3489 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3493 Motorola 68HC11 and 68HC12 m68hc11-elf
3495 UltraSparc running GNU/Linux sparc64-*-linux*
3497 * OBSOLETE configurations and files
3499 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3500 Harris/CXUX m88k m88*-harris-cxux*
3501 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3502 ns32k-utek-sysv* ns32k-utek-*
3503 TI TMS320C80 tic80-*-*
3505 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3506 PowerPC Solaris powerpcle-*-solaris*
3507 PowerPC Windows NT powerpcle-*-cygwin32
3508 PowerPC Netware powerpc-*-netware*
3509 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3510 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3511 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3512 Apple Macintosh (MPW) host N/A
3514 stuff.c (Program to stuff files into a specially prepared space in kdb)
3515 kdb-start.c (Main loop for the standalone kernel debugger)
3517 Configurations that have been declared obsolete in this release have
3518 been commented out. Unless there is activity to revive these
3519 configurations, the next release of GDB will have their sources
3520 permanently REMOVED.
3522 * REMOVED configurations and files
3524 Altos 3068 m68*-altos-*
3525 Convex c1-*-*, c2-*-*
3527 ARM RISCix arm-*-* (as host)
3531 * GDB has been converted to ISO C.
3533 GDB's source code has been converted to ISO C. In particular, the
3534 sources are fully protoized, and rely on standard headers being
3539 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3541 * The MI enabled by default.
3543 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3544 revised and enabled by default. Packages which use GDB as a debugging
3545 engine behind a UI or another front end are encouraged to switch to
3546 using the GDB/MI interface, instead of the old annotations interface
3547 which is now deprecated.
3549 * Support for debugging Pascal programs.
3551 GDB now includes support for debugging Pascal programs. The following
3552 main features are supported:
3554 - Pascal-specific data types such as sets;
3556 - automatic recognition of Pascal sources based on file-name
3559 - Pascal-style display of data types, variables, and functions;
3561 - a Pascal expression parser.
3563 However, some important features are not yet supported.
3565 - Pascal string operations are not supported at all;
3567 - there are some problems with boolean types;
3569 - Pascal type hexadecimal constants are not supported
3570 because they conflict with the internal variables format;
3572 - support for Pascal objects and classes is not full yet;
3574 - unlike Pascal, GDB is case-sensitive for symbol names.
3576 * Changes in completion.
3578 Commands such as `shell', `run' and `set args', which pass arguments
3579 to inferior programs, now complete on file names, similar to what
3580 users expect at the shell prompt.
3582 Commands which accept locations, such as `disassemble', `print',
3583 `breakpoint', `until', etc. now complete on filenames as well as
3584 program symbols. Thus, if you type "break foob TAB", and the source
3585 files linked into the programs include `foobar.c', that file name will
3586 be one of the candidates for completion. However, file names are not
3587 considered for completion after you typed a colon that delimits a file
3588 name from a name of a function in that file, as in "break foo.c:bar".
3590 `set demangle-style' completes on available demangling styles.
3592 * New platform-independent commands:
3594 It is now possible to define a post-hook for a command as well as a
3595 hook that runs before the command. For more details, see the
3596 documentation of `hookpost' in the GDB manual.
3598 * Changes in GNU/Linux native debugging.
3600 Support for debugging multi-threaded programs has been completely
3601 revised for all platforms except m68k and sparc. You can now debug as
3602 many threads as your system allows you to have.
3604 Attach/detach is supported for multi-threaded programs.
3606 Support for SSE registers was added for x86. This doesn't work for
3607 multi-threaded programs though.
3609 * Changes in MIPS configurations.
3611 Multi-arch support is enabled for all MIPS configurations.
3613 GDB can now be built as native debugger on SGI Irix 6.x systems for
3614 debugging n32 executables. (Debugging 64-bit executables is not yet
3617 * Unified support for hardware watchpoints in all x86 configurations.
3619 Most (if not all) native x86 configurations support hardware-assisted
3620 breakpoints and watchpoints in a unified manner. This support
3621 implements debug register sharing between watchpoints, which allows to
3622 put a virtually infinite number of watchpoints on the same address,
3623 and also supports watching regions up to 16 bytes with several debug
3626 The new maintenance command `maintenance show-debug-regs' toggles
3627 debugging print-outs in functions that insert, remove, and test
3628 watchpoints and hardware breakpoints.
3630 * Changes in the DJGPP native configuration.
3632 New command ``info dos sysinfo'' displays assorted information about
3633 the CPU, OS, memory, and DPMI server.
3635 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3636 display information about segment descriptors stored in GDT, LDT, and
3639 New commands ``info dos pde'' and ``info dos pte'' display entries
3640 from Page Directory and Page Tables (for now works with CWSDPMI only).
3641 New command ``info dos address-pte'' displays the Page Table entry for
3642 a given linear address.
3644 GDB can now pass command lines longer than 126 characters to the
3645 program being debugged (requires an update to the libdbg.a library
3646 which is part of the DJGPP development kit).
3648 DWARF2 debug info is now supported.
3650 It is now possible to `step' and `next' through calls to `longjmp'.
3652 * Changes in documentation.
3654 All GDB documentation was converted to GFDL, the GNU Free
3655 Documentation License.
3657 Tracepoints-related commands are now fully documented in the GDB
3660 TUI, the Text-mode User Interface, is now documented in the manual.
3662 Tracepoints-related commands are now fully documented in the GDB
3665 The "GDB Internals" manual now has an index. It also includes
3666 documentation of `ui_out' functions, GDB coding standards, x86
3667 hardware watchpoints, and memory region attributes.
3669 * GDB's version number moved to ``version.in''
3671 The Makefile variable VERSION has been replaced by the file
3672 ``version.in''. People creating GDB distributions should update the
3673 contents of this file.
3677 GUD support is now a standard part of the EMACS distribution.
3679 *** Changes in GDB 5.0:
3681 * Improved support for debugging FP programs on x86 targets
3683 Unified and much-improved support for debugging floating-point
3684 programs on all x86 targets. In particular, ``info float'' now
3685 displays the FP registers in the same format on all x86 targets, with
3686 greater level of detail.
3688 * Improvements and bugfixes in hardware-assisted watchpoints
3690 It is now possible to watch array elements, struct members, and
3691 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3692 on x86 targets no longer erroneously trigger when the address is
3695 * Improvements in the native DJGPP version of GDB
3697 The distribution now includes all the scripts and auxiliary files
3698 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3699 machines ``out of the box''.
3701 The DJGPP version can now debug programs that use signals. It is
3702 possible to catch signals that happened in the debuggee, deliver
3703 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3704 would kill the program being debugged.) Programs that hook hardware
3705 interrupts (keyboard, timer, etc.) can also be debugged.
3707 It is now possible to debug DJGPP programs that redirect their
3708 standard handles or switch them to raw (as opposed to cooked) mode, or
3709 even close them. The command ``run < foo > bar'' works as expected,
3710 and ``info terminal'' reports useful information about the debuggee's
3711 terminal, including raw/cooked mode, redirection, etc.
3713 The DJGPP version now uses termios functions for console I/O, which
3714 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3717 DOS-style file names with drive letters are now fully supported by
3720 It is now possible to debug DJGPP programs that switch their working
3721 directory. It is also possible to rerun the debuggee any number of
3722 times without restarting GDB; thus, you can use the same setup,
3723 breakpoints, etc. for many debugging sessions.
3725 * New native configurations
3727 ARM GNU/Linux arm*-*-linux*
3728 PowerPC GNU/Linux powerpc-*-linux*
3732 Motorola MCore mcore-*-*
3733 x86 VxWorks i[3456]86-*-vxworks*
3734 PowerPC VxWorks powerpc-*-vxworks*
3735 TI TMS320C80 tic80-*-*
3737 * OBSOLETE configurations
3739 Altos 3068 m68*-altos-*
3740 Convex c1-*-*, c2-*-*
3742 ARM RISCix arm-*-* (as host)
3745 Configurations that have been declared obsolete will be commented out,
3746 but the code will be left in place. If there is no activity to revive
3747 these configurations before the next release of GDB, the sources will
3748 be permanently REMOVED.
3750 * Gould support removed
3752 Support for the Gould PowerNode and NP1 has been removed.
3754 * New features for SVR4
3756 On SVR4 native platforms (such as Solaris), if you attach to a process
3757 without first loading a symbol file, GDB will now attempt to locate and
3758 load symbols from the running process's executable file.
3760 * Many C++ enhancements
3762 C++ support has been greatly improved. Overload resolution now works properly
3763 in almost all cases. RTTI support is on the way.
3765 * Remote targets can connect to a sub-program
3767 A popen(3) style serial-device has been added. This device starts a
3768 sub-process (such as a stand-alone simulator) and then communicates
3769 with that. The sub-program to run is specified using the syntax
3770 ``|<program> <args>'' vis:
3772 (gdb) set remotedebug 1
3773 (gdb) target extended-remote |mn10300-elf-sim program-args
3775 * MIPS 64 remote protocol
3777 A long standing bug in the mips64 remote protocol where by GDB
3778 expected certain 32 bit registers (ex SR) to be transfered as 32
3779 instead of 64 bits has been fixed.
3781 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3782 added to provide backward compatibility with older versions of GDB.
3784 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3786 The command ``set remotebinarydownload'' command has been replaced by
3787 ``set remote X-packet''. Other commands in ``set remote'' family
3788 include ``set remote P-packet''.
3790 * Breakpoint commands accept ranges.
3792 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3793 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3794 ``tracepoint passcount'' also accepts a range of tracepoints.
3796 * ``apropos'' command added.
3798 The ``apropos'' command searches through command names and
3799 documentation strings, printing out matches, making it much easier to
3800 try to find a command that does what you are looking for.
3804 A new machine oriented interface (MI) has been added to GDB. This
3805 interface is designed for debug environments running GDB as a separate
3806 process. This is part of the long term libGDB project. See the
3807 "GDB/MI" chapter of the GDB manual for further information. It can be
3808 enabled by configuring with:
3810 .../configure --enable-gdbmi
3812 *** Changes in GDB-4.18:
3814 * New native configurations
3816 HP-UX 10.20 hppa*-*-hpux10.20
3817 HP-UX 11.x hppa*-*-hpux11.0*
3818 M68K GNU/Linux m68*-*-linux*
3822 Fujitsu FR30 fr30-*-elf*
3823 Intel StrongARM strongarm-*-*
3824 Mitsubishi D30V d30v-*-*
3826 * OBSOLETE configurations
3828 Gould PowerNode, NP1 np1-*-*, pn-*-*
3830 Configurations that have been declared obsolete will be commented out,
3831 but the code will be left in place. If there is no activity to revive
3832 these configurations before the next release of GDB, the sources will
3833 be permanently REMOVED.
3837 As a compatibility experiment, GDB's source files buildsym.h and
3838 buildsym.c have been converted to pure standard C, no longer
3839 containing any K&R compatibility code. We believe that all systems in
3840 use today either come with a standard C compiler, or have a GCC port
3841 available. If this is not true, please report the affected
3842 configuration to bug-gdb@gnu.org immediately. See the README file for
3843 information about getting a standard C compiler if you don't have one
3848 GDB now uses readline 2.2.
3850 * set extension-language
3852 You can now control the mapping between filename extensions and source
3853 languages by using the `set extension-language' command. For instance,
3854 you can ask GDB to treat .c files as C++ by saying
3855 set extension-language .c c++
3856 The command `info extensions' lists all of the recognized extensions
3857 and their associated languages.
3859 * Setting processor type for PowerPC and RS/6000
3861 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3862 you can use the `set processor' command to specify what variant of the
3863 PowerPC family you are debugging. The command
3867 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3868 following PowerPC and RS6000 variants:
3870 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3871 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3873 403GC IBM PowerPC 403GC
3874 505 Motorola PowerPC 505
3875 860 Motorola PowerPC 860 or 850
3876 601 Motorola PowerPC 601
3877 602 Motorola PowerPC 602
3878 603 Motorola/IBM PowerPC 603 or 603e
3879 604 Motorola PowerPC 604 or 604e
3880 750 Motorola/IBM PowerPC 750 or 750
3882 At the moment, this command just tells GDB what to name the
3883 special-purpose processor registers. Since almost all the affected
3884 registers are inaccessible to user-level programs, this command is
3885 only useful for remote debugging in its present form.
3889 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3890 more extensive support for HP-UX. Added features include shared
3891 library support, kernel threads and hardware watchpoints for 11.00,
3892 support for HP's ANSI C and C++ compilers, and a compatibility mode
3893 for xdb and dbx commands.
3897 HP's donation includes the new concept of catchpoints, which is a
3898 generalization of the old catch command. On HP-UX, it is now possible
3899 to catch exec, fork, and vfork, as well as library loading.
3901 This means that the existing catch command has changed; its first
3902 argument now specifies the type of catch to be set up. See the
3903 output of "help catch" for a list of catchpoint types.
3905 * Debugging across forks
3907 On HP-UX, you can choose which process to debug when a fork() happens
3912 HP has donated a curses-based terminal user interface (TUI). To get
3913 it, build with --enable-tui. Although this can be enabled for any
3914 configuration, at present it only works for native HP debugging.
3916 * GDB remote protocol additions
3918 A new protocol packet 'X' that writes binary data is now available.
3919 Default behavior is to try 'X', then drop back to 'M' if the stub
3920 fails to respond. The settable variable `remotebinarydownload'
3921 allows explicit control over the use of 'X'.
3923 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3924 full 64-bit address. The command
3926 set remoteaddresssize 32
3928 can be used to revert to the old behaviour. For existing remote stubs
3929 the change should not be noticed, as the additional address information
3932 In order to assist in debugging stubs, you may use the maintenance
3933 command `packet' to send any text string to the stub. For instance,
3935 maint packet heythere
3937 sends the packet "$heythere#<checksum>". Note that it is very easy to
3938 disrupt a debugging session by sending the wrong packet at the wrong
3941 The compare-sections command allows you to compare section data on the
3942 target to what is in the executable file without uploading or
3943 downloading, by comparing CRC checksums.
3945 * Tracing can collect general expressions
3947 You may now collect general expressions at tracepoints. This requires
3948 further additions to the target-side stub; see tracepoint.c and
3949 doc/agentexpr.texi for further details.
3951 * mask-address variable for Mips
3953 For Mips targets, you may control the zeroing of the upper 32 bits of
3954 a 64-bit address by entering `set mask-address on'. This is mainly
3955 of interest to users of embedded R4xxx and R5xxx processors.
3957 * Higher serial baud rates
3959 GDB's serial code now allows you to specify baud rates 57600, 115200,
3960 230400, and 460800 baud. (Note that your host system may not be able
3961 to achieve all of these rates.)
3965 The i960 configuration now includes an initial implementation of a
3966 builtin simulator, contributed by Jim Wilson.
3969 *** Changes in GDB-4.17:
3971 * New native configurations
3973 Alpha GNU/Linux alpha*-*-linux*
3974 Unixware 2.x i[3456]86-unixware2*
3975 Irix 6.x mips*-sgi-irix6*
3976 PowerPC GNU/Linux powerpc-*-linux*
3977 PowerPC Solaris powerpcle-*-solaris*
3978 Sparc GNU/Linux sparc-*-linux*
3979 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3983 Argonaut Risc Chip (ARC) arc-*-*
3984 Hitachi H8/300S h8300*-*-*
3985 Matsushita MN10200 w/simulator mn10200-*-*
3986 Matsushita MN10300 w/simulator mn10300-*-*
3987 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3988 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3989 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3990 Mitsubishi D10V w/simulator d10v-*-*
3991 Mitsubishi M32R/D w/simulator m32r-*-elf*
3992 Tsqware Sparclet sparclet-*-*
3993 NEC V850 w/simulator v850-*-*
3995 * New debugging protocols
3997 ARM with RDI protocol arm*-*-*
3998 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3999 DDB and LSI variants of PMON protocol mips*-*-*
4000 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4001 PowerPC with SDS protocol powerpc{,le}-*-eabi
4002 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4006 All configurations can now understand and use the DWARF 2 debugging
4007 format. The choice is automatic, if the symbol file contains DWARF 2
4012 GDB now includes basic Java language support. This support is
4013 only useful with Java compilers that produce native machine code.
4015 * solib-absolute-prefix and solib-search-path
4017 For SunOS and SVR4 shared libraries, you may now set the prefix for
4018 loading absolute shared library symbol files, and the search path for
4019 locating non-absolute shared library symbol files.
4021 * Live range splitting
4023 GDB can now effectively debug code for which GCC has performed live
4024 range splitting as part of its optimization. See gdb/doc/LRS for
4025 more details on the expected format of the stabs information.
4029 GDB's support for the GNU Hurd, including thread debugging, has been
4030 updated to work with current versions of the Hurd.
4034 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4035 instruction set. ARM GDB automatically detects when Thumb
4036 instructions are in use, and adjusts disassembly and backtracing
4041 GDB's MIPS target configurations now handle the MIP16 16-bit
4046 GDB now includes support for overlays; if an executable has been
4047 linked such that multiple sections are based at the same address, GDB
4048 will decide which section to use for symbolic info. You can choose to
4049 control the decision manually, using overlay commands, or implement
4050 additional target-side support and use "overlay load-target" to bring
4051 in the overlay mapping. Do "help overlay" for more detail.
4055 The command "info symbol <address>" displays information about
4056 the symbol at the specified address.
4060 The standard remote protocol now includes an extension that allows
4061 asynchronous collection and display of trace data. This requires
4062 extensive support in the target-side debugging stub. Tracing mode
4063 includes a new interaction mode in GDB and new commands: see the
4064 file tracepoint.c for more details.
4068 Configurations for embedded MIPS now include a simulator contributed
4069 by Cygnus Solutions. The simulator supports the instruction sets
4070 of most MIPS variants.
4074 Sparc configurations may now include the ERC32 simulator contributed
4075 by the European Space Agency. The simulator is not built into
4076 Sparc targets by default; configure with --enable-sim to include it.
4080 For target configurations that may include multiple variants of a
4081 basic architecture (such as MIPS and SH), you may now set the
4082 architecture explicitly. "set arch" sets, "info arch" lists
4083 the possible architectures.
4085 *** Changes in GDB-4.16:
4087 * New native configurations
4089 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4090 M68K NetBSD m68k-*-netbsd*
4091 PowerPC AIX 4.x powerpc-*-aix*
4092 PowerPC MacOS powerpc-*-macos*
4093 PowerPC Windows NT powerpcle-*-cygwin32
4094 RS/6000 AIX 4.x rs6000-*-aix4*
4098 ARM with RDP protocol arm-*-*
4099 I960 with MON960 i960-*-coff
4100 MIPS VxWorks mips*-*-vxworks*
4101 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4102 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4104 Matra Sparclet sparclet-*-*
4108 The powerpc-eabi configuration now includes the PSIM simulator,
4109 contributed by Andrew Cagney, with assistance from Mike Meissner.
4110 PSIM is a very elaborate model of the PowerPC, including not only
4111 basic instruction set execution, but also details of execution unit
4112 performance and I/O hardware. See sim/ppc/README for more details.
4116 GDB now works with Solaris 2.5.
4118 * Windows 95/NT native
4120 GDB will now work as a native debugger on Windows 95 and Windows NT.
4121 To build it from source, you must use the "gnu-win32" environment,
4122 which uses a DLL to emulate enough of Unix to run the GNU tools.
4123 Further information, binaries, and sources are available at
4124 ftp.cygnus.com, under pub/gnu-win32.
4126 * dont-repeat command
4128 If a user-defined command includes the command `dont-repeat', then the
4129 command will not be repeated if the user just types return. This is
4130 useful if the command is time-consuming to run, so that accidental
4131 extra keystrokes don't run the same command many times.
4133 * Send break instead of ^C
4135 The standard remote protocol now includes an option to send a break
4136 rather than a ^C to the target in order to interrupt it. By default,
4137 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4139 * Remote protocol timeout
4141 The standard remote protocol includes a new variable `remotetimeout'
4142 that allows you to set the number of seconds before GDB gives up trying
4143 to read from the target. The default value is 2.
4145 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4147 By default GDB will automatically keep track of objects as they are
4148 loaded and unloaded by the dynamic linker. By using the command `set
4149 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4150 when shared library events occur, thus allowing you to set breakpoints
4151 in shared libraries which are explicitly loaded by the inferior.
4153 Note this feature does not work on hpux8. On hpux9 you must link
4154 /usr/lib/end.o into your program. This feature should work
4155 automatically on hpux10.
4157 * Irix 5.x hardware watchpoint support
4159 Irix 5 configurations now support the use of hardware watchpoints.
4161 * Mips protocol "SYN garbage limit"
4163 When debugging a Mips target using the `target mips' protocol, you
4164 may set the number of characters that GDB will ignore by setting
4165 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4166 every character. The default value is 1050.
4168 * Recording and replaying remote debug sessions
4170 If you set `remotelogfile' to the name of a file, gdb will write to it
4171 a recording of a remote debug session. This recording may then be
4172 replayed back to gdb using "gdbreplay". See gdbserver/README for
4173 details. This is useful when you have a problem with GDB while doing
4174 remote debugging; you can make a recording of the session and send it
4175 to someone else, who can then recreate the problem.
4177 * Speedups for remote debugging
4179 GDB includes speedups for downloading and stepping MIPS systems using
4180 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4181 and more efficient S-record downloading.
4183 * Memory use reductions and statistics collection
4185 GDB now uses less memory and reports statistics about memory usage.
4186 Try the `maint print statistics' command, for example.
4188 *** Changes in GDB-4.15:
4190 * Psymtabs for XCOFF
4192 The symbol reader for AIX GDB now uses partial symbol tables. This
4193 can greatly improve startup time, especially for large executables.
4195 * Remote targets use caching
4197 Remote targets now use a data cache to speed up communication with the
4198 remote side. The data cache could lead to incorrect results because
4199 it doesn't know about volatile variables, thus making it impossible to
4200 debug targets which use memory mapped I/O devices. `set remotecache
4201 off' turns the the data cache off.
4203 * Remote targets may have threads
4205 The standard remote protocol now includes support for multiple threads
4206 in the target system, using new protocol commands 'H' and 'T'. See
4207 gdb/remote.c for details.
4211 If GDB is configured with `--enable-netrom', then it will include
4212 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4213 acts as though it is a bank of ROM on the target board, but you can
4214 write into it over the network. GDB's support consists only of
4215 support for fast loading into the emulated ROM; to debug, you must use
4216 another protocol, such as standard remote protocol. The usual
4217 sequence is something like
4219 target nrom <netrom-hostname>
4221 target remote <netrom-hostname>:1235
4225 GDB now includes support for the Apple Macintosh, as a host only. It
4226 may be run as either an MPW tool or as a standalone application, and
4227 it can debug through the serial port. All the usual GDB commands are
4228 available, but to the target command, you must supply "serial" as the
4229 device type instead of "/dev/ttyXX". See mpw-README in the main
4230 directory for more information on how to build. The MPW configuration
4231 scripts */mpw-config.in support only a few targets, and only the
4232 mips-idt-ecoff target has been tested.
4236 GDB configuration now uses autoconf. This is not user-visible,
4237 but does simplify configuration and building.
4241 GDB now supports hpux10.
4243 *** Changes in GDB-4.14:
4245 * New native configurations
4247 x86 FreeBSD i[345]86-*-freebsd
4248 x86 NetBSD i[345]86-*-netbsd
4249 NS32k NetBSD ns32k-*-netbsd
4250 Sparc NetBSD sparc-*-netbsd
4254 A29K VxWorks a29k-*-vxworks
4255 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4256 CPU32 EST-300 emulator m68*-*-est*
4257 PowerPC ELF powerpc-*-elf
4260 * Alpha OSF/1 support for procfs
4262 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4263 possible to attach to running processes. As the mounting of the /proc
4264 filesystem is optional on the Alpha, GDB automatically determines
4265 the availability of /proc during startup. This can lead to problems
4266 if /proc is unmounted after GDB has been started.
4268 * Arguments to user-defined commands
4270 User commands may accept up to 10 arguments separated by whitespace.
4271 Arguments are accessed within the user command via $arg0..$arg9. A
4274 print $arg0 + $arg1 + $arg2
4276 To execute the command use:
4279 Defines the command "adder" which prints the sum of its three arguments.
4280 Note the arguments are text substitutions, so they may reference variables,
4281 use complex expressions, or even perform inferior function calls.
4283 * New `if' and `while' commands
4285 This makes it possible to write more sophisticated user-defined
4286 commands. Both commands take a single argument, which is the
4287 expression to evaluate, and must be followed by the commands to
4288 execute, one per line, if the expression is nonzero, the list being
4289 terminated by the word `end'. The `if' command list may include an
4290 `else' word, which causes the following commands to be executed only
4291 if the expression is zero.
4293 * Fortran source language mode
4295 GDB now includes partial support for Fortran 77. It will recognize
4296 Fortran programs and can evaluate a subset of Fortran expressions, but
4297 variables and functions may not be handled correctly. GDB will work
4298 with G77, but does not yet know much about symbols emitted by other
4301 * Better HPUX support
4303 Most debugging facilities now work on dynamic executables for HPPAs
4304 running hpux9 or later. You can attach to running dynamically linked
4305 processes, but by default the dynamic libraries will be read-only, so
4306 for instance you won't be able to put breakpoints in them. To change
4307 that behavior do the following before running the program:
4313 This will cause the libraries to be mapped private and read-write.
4314 To revert to the normal behavior, do this:
4320 You cannot set breakpoints or examine data in the library until after
4321 the library is loaded if the function/data symbols do not have
4324 GDB can now also read debug symbols produced by the HP C compiler on
4325 HPPAs (sorry, no C++, Fortran or 68k support).
4327 * Target byte order now dynamically selectable
4329 You can choose which byte order to use with a target system, via the
4330 commands "set endian big" and "set endian little", and you can see the
4331 current setting by using "show endian". You can also give the command
4332 "set endian auto", in which case GDB will use the byte order
4333 associated with the executable. Currently, only embedded MIPS
4334 configurations support dynamic selection of target byte order.
4336 * New DOS host serial code
4338 This version uses DPMI interrupts to handle buffered I/O, so you
4339 no longer need to run asynctsr when debugging boards connected to
4342 *** Changes in GDB-4.13:
4344 * New "complete" command
4346 This lists all the possible completions for the rest of the line, if it
4347 were to be given as a command itself. This is intended for use by emacs.
4349 * Trailing space optional in prompt
4351 "set prompt" no longer adds a space for you after the prompt you set. This
4352 allows you to set a prompt which ends in a space or one that does not.
4354 * Breakpoint hit counts
4356 "info break" now displays a count of the number of times the breakpoint
4357 has been hit. This is especially useful in conjunction with "ignore"; you
4358 can ignore a large number of breakpoint hits, look at the breakpoint info
4359 to see how many times the breakpoint was hit, then run again, ignoring one
4360 less than that number, and this will get you quickly to the last hit of
4363 * Ability to stop printing at NULL character
4365 "set print null-stop" will cause GDB to stop printing the characters of
4366 an array when the first NULL is encountered. This is useful when large
4367 arrays actually contain only short strings.
4369 * Shared library breakpoints
4371 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4372 breakpoints in shared libraries before the executable is run.
4374 * Hardware watchpoints
4376 There is a new hardware breakpoint for the watch command for sparclite
4377 targets. See gdb/sparclite/hw_breakpoint.note.
4379 Hardware watchpoints are also now supported under GNU/Linux.
4383 Annotations have been added. These are for use with graphical interfaces,
4384 and are still experimental. Currently only gdba.el uses these.
4386 * Improved Irix 5 support
4388 GDB now works properly with Irix 5.2.
4390 * Improved HPPA support
4392 GDB now works properly with the latest GCC and GAS.
4394 * New native configurations
4396 Sequent PTX4 i[34]86-sequent-ptx4
4397 HPPA running OSF/1 hppa*-*-osf*
4398 Atari TT running SVR4 m68*-*-sysv4*
4399 RS/6000 LynxOS rs6000-*-lynxos*
4403 OS/9000 i[34]86-*-os9k
4404 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4407 * Hitachi SH7000 and E7000-PC ICE support
4409 There is now support for communicating with the Hitachi E7000-PC ICE.
4410 This is available automatically when GDB is configured for the SH.
4414 As usual, a variety of small fixes and improvements, both generic
4415 and configuration-specific. See the ChangeLog for more detail.
4417 *** Changes in GDB-4.12:
4419 * Irix 5 is now supported
4423 GDB-4.12 on the HPPA has a number of changes which make it unable
4424 to debug the output from the currently released versions of GCC and
4425 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4426 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4427 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4430 *** Changes in GDB-4.11:
4432 * User visible changes:
4436 The "set remotedebug" option is now consistent between the mips remote
4437 target, remote targets using the gdb-specific protocol, UDI (AMD's
4438 debug protocol for the 29k) and the 88k bug monitor. It is now an
4439 integer specifying a debug level (normally 0 or 1, but 2 means more
4440 debugging info for the mips target).
4442 * DEC Alpha native support
4444 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4445 debug info, but GDB works fairly well with the DEC compiler and should
4446 work with a future GCC release. See the README file for a few
4447 Alpha-specific notes.
4449 * Preliminary thread implementation
4451 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4453 * LynxOS native and target support for 386
4455 This release has been hosted on LynxOS 2.2, and also can be configured
4456 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4459 * Improvements in C++ mangling/demangling.
4461 This release has much better g++ debugging, specifically in name
4462 mangling/demangling, virtual function calls, print virtual table,
4463 call methods, ...etc.
4465 *** Changes in GDB-4.10:
4467 * User visible changes:
4469 Remote debugging using the GDB-specific (`target remote') protocol now
4470 supports the `load' command. This is only useful if you have some
4471 other way of getting the stub to the target system, and you can put it
4472 somewhere in memory where it won't get clobbered by the download.
4474 Filename completion now works.
4476 When run under emacs mode, the "info line" command now causes the
4477 arrow to point to the line specified. Also, "info line" prints
4478 addresses in symbolic form (as well as hex).
4480 All vxworks based targets now support a user settable option, called
4481 vxworks-timeout. This option represents the number of seconds gdb
4482 should wait for responses to rpc's. You might want to use this if
4483 your vxworks target is, perhaps, a slow software simulator or happens
4484 to be on the far side of a thin network line.
4488 This release contains support for using a DEC alpha as a GDB host for
4489 cross debugging. Native alpha debugging is not supported yet.
4492 *** Changes in GDB-4.9:
4496 This is the first GDB release which is accompanied by a matching testsuite.
4497 The testsuite requires installation of dejagnu, which should be available
4498 via ftp from most sites that carry GNU software.
4502 'Cfront' style demangling has had its name changed to 'ARM' style, to
4503 emphasize that it was written from the specifications in the C++ Annotated
4504 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4505 disclaimers, it still generated too much confusion with users attempting to
4506 use gdb with AT&T cfront.
4510 GDB now uses a standard remote interface to a simulator library.
4511 So far, the library contains simulators for the Zilog Z8001/2, the
4512 Hitachi H8/300, H8/500 and Super-H.
4514 * New targets supported
4516 H8/300 simulator h8300-hitachi-hms or h8300hms
4517 H8/500 simulator h8500-hitachi-hms or h8500hms
4518 SH simulator sh-hitachi-hms or sh
4519 Z8000 simulator z8k-zilog-none or z8ksim
4520 IDT MIPS board over serial line mips-idt-ecoff
4522 Cross-debugging to GO32 targets is supported. It requires a custom
4523 version of the i386-stub.c module which is integrated with the
4524 GO32 memory extender.
4526 * New remote protocols
4528 MIPS remote debugging protocol.
4530 * New source languages supported
4532 This version includes preliminary support for Chill, a Pascal like language
4533 used by telecommunications companies. Chill support is also being integrated
4534 into the GNU compiler, but we don't know when it will be publically available.
4537 *** Changes in GDB-4.8:
4539 * HP Precision Architecture supported
4541 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4542 version of this support was available as a set of patches from the
4543 University of Utah. GDB does not support debugging of programs
4544 compiled with the HP compiler, because HP will not document their file
4545 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4546 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4548 Many problems in the preliminary version have been fixed.
4550 * Faster and better demangling
4552 We have improved template demangling and fixed numerous bugs in the GNU style
4553 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4554 character types (wchar_t) are now supported. Demangling of each symbol is now
4555 only done once, and is cached when the symbol table for a file is read in.
4556 This results in a small increase in memory usage for C programs, a moderate
4557 increase in memory usage for C++ programs, and a fantastic speedup in
4560 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4561 from the specifications in the Annotated Reference Manual, which AT&T's
4562 compiler does not actually implement.
4564 * G++ multiple inheritance compiler problem
4566 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4567 inheritance lattices was reworked to properly discover ambiguities. We
4568 recently found an example which causes this new algorithm to fail in a
4569 very subtle way, producing bad debug information for those classes.
4570 The file 'gcc.patch' (in this directory) can be applied to gcc to
4571 circumvent the problem. A future GCC release will contain a complete
4574 The previous G++ debug info problem (mentioned below for the gdb-4.7
4575 release) is fixed in gcc version 2.3.2.
4577 * Improved configure script
4579 The `configure' script will now attempt to guess your system type if
4580 you don't supply a host system type. The old scheme of supplying a
4581 host system triplet is preferable over using this. All the magic is
4582 done in the new `config.guess' script. Examine it for details.
4584 We have also brought our configure script much more in line with the FSF's
4585 version. It now supports the --with-xxx options. In particular,
4586 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4587 The resulting GDB will not be able to read arbitrary object file formats --
4588 only the format ``expected'' to be used on the configured target system.
4589 We hope to make this the default in a future release.
4591 * Documentation improvements
4593 There's new internal documentation on how to modify GDB, and how to
4594 produce clean changes to the code. We implore people to read it
4595 before submitting changes.
4597 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4598 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4599 `info' files are also provided. To build `info' files from scratch,
4600 you will need the latest `makeinfo' release, which will be available in
4601 a future texinfo-X.Y release.
4603 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4604 We're not sure exactly which versions have this problem, but it has
4605 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4606 or better. If that isn't possible, there is a patch in
4607 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4608 around this problem.
4612 GDB now supports array constants that can be used in expressions typed in by
4613 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4614 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4617 The new directory `gdb/sparclite' contains a program that demonstrates
4618 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4620 * New native hosts supported
4622 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4623 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4625 * New targets supported
4627 AMD 29k family via UDI a29k-amd-udi or udi29k
4629 * New file formats supported
4631 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4632 HPUX core files, and SCO 3.2v2 core files.
4636 Attaching to processes now works again; thanks for the many bug reports.
4638 We have also stomped on a bunch of core dumps caused by
4639 printf_filtered("%s") problems.
4641 We eliminated a copyright problem on the rpc and ptrace header files
4642 for VxWorks, which was discovered at the last minute during the 4.7
4643 release. You should now be able to build a VxWorks GDB.
4645 You can now interrupt gdb while an attached process is running. This
4646 will cause the attached process to stop, and give control back to GDB.
4648 We fixed problems caused by using too many file descriptors
4649 for reading symbols from object files and libraries. This was
4650 especially a problem for programs that used many (~100) shared
4653 The `step' command now only enters a subroutine if there is line number
4654 information for the subroutine. Otherwise it acts like the `next'
4655 command. Previously, `step' would enter subroutines if there was
4656 any debugging information about the routine. This avoids problems
4657 when using `cc -g1' on MIPS machines.
4659 * Internal improvements
4661 GDB's internal interfaces have been improved to make it easier to support
4662 debugging of multiple languages in the future.
4664 GDB now uses a common structure for symbol information internally.
4665 Minimal symbols (derived from linkage symbols in object files), partial
4666 symbols (from a quick scan of debug information), and full symbols
4667 contain a common subset of information, making it easier to write
4668 shared code that handles any of them.
4670 * New command line options
4672 We now accept --silent as an alias for --quiet.
4676 The memory-mapped-malloc library is now licensed under the GNU Library
4677 General Public License.
4679 *** Changes in GDB-4.7:
4681 * Host/native/target split
4683 GDB has had some major internal surgery to untangle the support for
4684 hosts and remote targets. Now, when you configure GDB for a remote
4685 target, it will no longer load in all of the support for debugging
4686 local programs on the host. When fully completed and tested, this will
4687 ensure that arbitrary host/target combinations are possible.
4689 The primary conceptual shift is to separate the non-portable code in
4690 GDB into three categories. Host specific code is required any time GDB
4691 is compiled on that host, regardless of the target. Target specific
4692 code relates to the peculiarities of the target, but can be compiled on
4693 any host. Native specific code is everything else: it can only be
4694 built when the host and target are the same system. Child process
4695 handling and core file support are two common `native' examples.
4697 GDB's use of /proc for controlling Unix child processes is now cleaner.
4698 It has been split out into a single module under the `target_ops' vector,
4699 plus two native-dependent functions for each system that uses /proc.
4701 * New hosts supported
4703 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4704 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4705 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4707 * New targets supported
4709 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4710 68030 and CPU32 m68030-*-*, m68332-*-*
4712 * New native hosts supported
4714 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4715 (386bsd is not well tested yet)
4716 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4718 * New file formats supported
4720 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4721 supports reading of `a.out.adobe' object files, which are an a.out
4722 format extended with minimal information about multiple sections.
4726 `show copying' is the same as the old `info copying'.
4727 `show warranty' is the same as `info warrantee'.
4728 These were renamed for consistency. The old commands continue to work.
4730 `info handle' is a new alias for `info signals'.
4732 You can now define pre-command hooks, which attach arbitrary command
4733 scripts to any command. The commands in the hook will be executed
4734 prior to the user's command. You can also create a hook which will be
4735 executed whenever the program stops. See gdb.texinfo.
4739 We now deal with Cfront style name mangling, and can even extract type
4740 info from mangled symbols. GDB can automatically figure out which
4741 symbol mangling style your C++ compiler uses.
4743 Calling of methods and virtual functions has been improved as well.
4747 The crash that occured when debugging Sun Ansi-C compiled binaries is
4748 fixed. This was due to mishandling of the extra N_SO stabs output
4751 We also finally got Ultrix 4.2 running in house, and fixed core file
4752 support, with help from a dozen people on the net.
4754 John M. Farrell discovered that the reason that single-stepping was so
4755 slow on all of the Mips based platforms (primarily SGI and DEC) was
4756 that we were trying to demangle and lookup a symbol used for internal
4757 purposes on every instruction that was being stepped through. Changing
4758 the name of that symbol so that it couldn't be mistaken for a C++
4759 mangled symbol sped things up a great deal.
4761 Rich Pixley sped up symbol lookups in general by getting much smarter
4762 about when C++ symbol mangling is necessary. This should make symbol
4763 completion (TAB on the command line) much faster. It's not as fast as
4764 we'd like, but it's significantly faster than gdb-4.6.
4768 A new user controllable variable 'call_scratch_address' can
4769 specify the location of a scratch area to be used when GDB
4770 calls a function in the target. This is necessary because the
4771 usual method of putting the scratch area on the stack does not work
4772 in systems that have separate instruction and data spaces.
4774 We integrated changes to support the 29k UDI (Universal Debugger
4775 Interface), but discovered at the last minute that we didn't have all
4776 of the appropriate copyright paperwork. We are working with AMD to
4777 resolve this, and hope to have it available soon.
4781 We have sped up the remote serial line protocol, especially for targets
4782 with lots of registers. It now supports a new `expedited status' ('T')
4783 message which can be used in place of the existing 'S' status message.
4784 This allows the remote stub to send only the registers that GDB
4785 needs to make a quick decision about single-stepping or conditional
4786 breakpoints, eliminating the need to fetch the entire register set for
4787 each instruction being stepped through.
4789 The GDB remote serial protocol now implements a write-through cache for
4790 registers, only re-reading the registers if the target has run.
4792 There is also a new remote serial stub for SPARC processors. You can
4793 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4794 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4795 processor with a serial port.
4799 Configure.in files have become much easier to read and modify. A new
4800 `table driven' format makes it more obvious what configurations are
4801 supported, and what files each one uses.
4805 There is a new opcodes library which will eventually contain all of the
4806 disassembly routines and opcode tables. At present, it only contains
4807 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4808 disassembler (binutils/objdump) to share these routines.
4810 The libiberty library is now copylefted under the GNU Library General
4811 Public License. This allows more liberal use, and was done so libg++
4812 can use it. This makes no difference to GDB, since the Library License
4813 grants all the rights from the General Public License.
4817 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4818 reference to the stabs symbol info used by the debugger. It is (as far
4819 as we know) the only published document on this fascinating topic. We
4820 encourage you to read it, compare it to the stabs information on your
4821 system, and send improvements on the document in general (to
4822 bug-gdb@prep.ai.mit.edu).
4824 And, of course, many bugs have been fixed.
4827 *** Changes in GDB-4.6:
4829 * Better support for C++ function names
4831 GDB now accepts as input the "demangled form" of C++ overloaded function
4832 names and member function names, and can do command completion on such names
4833 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4834 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4835 Make use of command completion, it is your friend.
4837 GDB also now accepts a variety of C++ mangled symbol formats. They are
4838 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4839 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4840 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4841 for the list of formats.
4843 * G++ symbol mangling problem
4845 Recent versions of gcc have a bug in how they emit debugging information for
4846 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4847 directory) can be applied to gcc to fix the problem. Alternatively, if you
4848 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4849 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4850 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4853 * New 'maintenance' command
4855 All of the commands related to hacking GDB internals have been moved out of
4856 the main command set, and now live behind the 'maintenance' command. This
4857 can also be abbreviated as 'mt'. The following changes were made:
4859 dump-me -> maintenance dump-me
4860 info all-breakpoints -> maintenance info breakpoints
4861 printmsyms -> maintenance print msyms
4862 printobjfiles -> maintenance print objfiles
4863 printpsyms -> maintenance print psymbols
4864 printsyms -> maintenance print symbols
4866 The following commands are new:
4868 maintenance demangle Call internal GDB demangler routine to
4869 demangle a C++ link name and prints the result.
4870 maintenance print type Print a type chain for a given symbol
4872 * Change to .gdbinit file processing
4874 We now read the $HOME/.gdbinit file before processing the argv arguments
4875 (e.g. reading symbol files or core files). This allows global parameters to
4876 be set, which will apply during the symbol reading. The ./.gdbinit is still
4877 read after argv processing.
4879 * New hosts supported
4881 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4883 GNU/Linux support i386-unknown-linux or linux
4885 We are also including code to support the HP/PA running BSD and HPUX. This
4886 is almost guaranteed not to work, as we didn't have time to test or build it
4887 for this release. We are including it so that the more adventurous (or
4888 masochistic) of you can play with it. We also had major problems with the
4889 fact that the compiler that we got from HP doesn't support the -g option.
4892 * New targets supported
4894 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4896 * More smarts about finding #include files
4898 GDB now remembers the compilation directory for all include files, and for
4899 all files from which C is generated (like yacc and lex sources). This
4900 greatly improves GDB's ability to find yacc/lex sources, and include files,
4901 especially if you are debugging your program from a directory different from
4902 the one that contains your sources.
4904 We also fixed a bug which caused difficulty with listing and setting
4905 breakpoints in include files which contain C code. (In the past, you had to
4906 try twice in order to list an include file that you hadn't looked at before.)
4908 * Interesting infernals change
4910 GDB now deals with arbitrary numbers of sections, where the symbols for each
4911 section must be relocated relative to that section's landing place in the
4912 target's address space. This work was needed to support ELF with embedded
4913 stabs used by Solaris-2.0.
4915 * Bug fixes (of course!)
4917 There have been loads of fixes for the following things:
4918 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4919 i960, stabs, DOS(GO32), procfs, etc...
4921 See the ChangeLog for details.
4923 *** Changes in GDB-4.5:
4925 * New machines supported (host and target)
4927 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4929 SGI Irix-4.x mips-sgi-irix4 or iris4
4931 * New malloc package
4933 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4934 Mmalloc is capable of handling mutiple heaps of memory. It is also
4935 capable of saving a heap to a file, and then mapping it back in later.
4936 This can be used to greatly speedup the startup of GDB by using a
4937 pre-parsed symbol table which lives in a mmalloc managed heap. For
4938 more details, please read mmalloc/mmalloc.texi.
4942 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4943 'help info proc' for details.
4945 * MIPS ecoff symbol table format
4947 The code that reads MIPS symbol table format is now supported on all hosts.
4948 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4951 * File name changes for MS-DOS
4953 Many files in the config directories have been renamed to make it easier to
4954 support GDB on MS-DOSe systems (which have very restrictive file name
4955 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4956 environment) is close to working but has some remaining problems. Note
4957 that debugging of DOS programs is not supported, due to limitations
4958 in the ``operating system'', but it can be used to host cross-debugging.
4960 * Cross byte order fixes
4962 Many fixes have been made to support cross debugging of Sparc and MIPS
4963 targets from hosts whose byte order differs.
4965 * New -mapped and -readnow options
4967 If memory-mapped files are available on your system through the 'mmap'
4968 system call, you can use the -mapped option on the `file' or
4969 `symbol-file' commands to cause GDB to write the symbols from your
4970 program into a reusable file. If the program you are debugging is
4971 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4972 Future GDB debugging sessions will notice the presence of this file,
4973 and will quickly map in symbol information from it, rather than reading
4974 the symbol table from the executable program. Using the '-mapped'
4975 option in a GDB `file' or `symbol-file' command has the same effect as
4976 starting GDB with the '-mapped' command-line option.
4978 You can cause GDB to read the entire symbol table immediately by using
4979 the '-readnow' option with any of the commands that load symbol table
4980 information (or on the GDB command line). This makes the command
4981 slower, but makes future operations faster.
4983 The -mapped and -readnow options are typically combined in order to
4984 build a `fred.syms' file that contains complete symbol information.
4985 A simple GDB invocation to do nothing but build a `.syms' file for future
4988 gdb -batch -nx -mapped -readnow programname
4990 The `.syms' file is specific to the host machine on which GDB is run.
4991 It holds an exact image of GDB's internal symbol table. It cannot be
4992 shared across multiple host platforms.
4994 * longjmp() handling
4996 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4997 siglongjmp() without losing control. This feature has not yet been ported to
4998 all systems. It currently works on many 386 platforms, all MIPS-based
4999 platforms (SGI, DECstation, etc), and Sun3/4.
5003 Preliminary work has been put in to support the new Solaris OS from Sun. At
5004 this time, it can control and debug processes, but it is not capable of
5009 As always, many many bug fixes. The major areas were with g++, and mipsread.
5010 People using the MIPS-based platforms should experience fewer mysterious
5011 crashes and trashed symbol tables.
5013 *** Changes in GDB-4.4:
5015 * New machines supported (host and target)
5017 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5019 BSD Reno on Vax vax-dec-bsd
5020 Ultrix on Vax vax-dec-ultrix
5022 * New machines supported (target)
5024 AMD 29000 embedded, using EBMON a29k-none-none
5028 GDB continues to improve its handling of C++. `References' work better.
5029 The demangler has also been improved, and now deals with symbols mangled as
5030 per the Annotated C++ Reference Guide.
5032 GDB also now handles `stabs' symbol information embedded in MIPS
5033 `ecoff' symbol tables. Since the ecoff format was not easily
5034 extensible to handle new languages such as C++, this appeared to be a
5035 good way to put C++ debugging info into MIPS binaries. This option
5036 will be supported in the GNU C compiler, version 2, when it is
5039 * New features for SVR4
5041 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5042 shared libraries. Debugging dynamically linked programs should present
5043 only minor differences from debugging statically linked programs.
5045 The `info proc' command will print out information about any process
5046 on an SVR4 system (including the one you are debugging). At the moment,
5047 it prints the address mappings of the process.
5049 If you bring up GDB on another SVR4 system, please send mail to
5050 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5052 * Better dynamic linking support in SunOS
5054 Reading symbols from shared libraries which contain debugging symbols
5055 now works properly. However, there remain issues such as automatic
5056 skipping of `transfer vector' code during function calls, which
5057 make it harder to debug code in a shared library, than to debug the
5058 same code linked statically.
5062 GDB is now using the latest `getopt' routines from the FSF. This
5063 version accepts the -- prefix for options with long names. GDB will
5064 continue to accept the old forms (-option and +option) as well.
5065 Various single letter abbreviations for options have been explicity
5066 added to the option table so that they won't get overshadowed in the
5067 future by other options that begin with the same letter.
5071 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5072 Many assorted bugs have been handled. Many more remain to be handled.
5073 See the various ChangeLog files (primarily in gdb and bfd) for details.
5076 *** Changes in GDB-4.3:
5078 * New machines supported (host and target)
5080 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5081 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5082 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5084 * Almost SCO Unix support
5086 We had hoped to support:
5087 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5088 (except for core file support), but we discovered very late in the release
5089 that it has problems with process groups that render gdb unusable. Sorry
5090 about that. I encourage people to fix it and post the fixes.
5092 * Preliminary ELF and DWARF support
5094 GDB can read ELF object files on System V Release 4, and can handle
5095 debugging records for C, in DWARF format, in ELF files. This support
5096 is preliminary. If you bring up GDB on another SVR4 system, please
5097 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5102 GDB now uses the latest `readline' library. One user-visible change
5103 is that two tabs will list possible command completions, which previously
5104 required typing M-? (meta-question mark, or ESC ?).
5108 The `stepi' bug that many of you noticed has been squashed.
5109 Many bugs in C++ have been handled. Many more remain to be handled.
5110 See the various ChangeLog files (primarily in gdb and bfd) for details.
5112 * State of the MIPS world (in case you wondered):
5114 GDB can understand the symbol tables emitted by the compilers
5115 supplied by most vendors of MIPS-based machines, including DEC. These
5116 symbol tables are in a format that essentially nobody else uses.
5118 Some versions of gcc come with an assembler post-processor called
5119 mips-tfile. This program is required if you want to do source-level
5120 debugging of gcc-compiled programs. I believe FSF does not ship
5121 mips-tfile with gcc version 1, but it will eventually come with gcc
5124 Debugging of g++ output remains a problem. g++ version 1.xx does not
5125 really support it at all. (If you're lucky, you should be able to get
5126 line numbers and stack traces to work, but no parameters or local
5127 variables.) With some work it should be possible to improve the
5130 When gcc version 2 is released, you will have somewhat better luck.
5131 However, even then you will get confusing results for inheritance and
5134 We will eventually provide full debugging of g++ output on
5135 DECstations. This will probably involve some kind of stabs-in-ecoff
5136 encapulation, but the details have not been worked out yet.
5139 *** Changes in GDB-4.2:
5141 * Improved configuration
5143 Only one copy of `configure' exists now, and it is not self-modifying.
5144 Porting BFD is simpler.
5148 The `step' and `next' commands now only stop at the first instruction
5149 of a source line. This prevents the multiple stops that used to occur
5150 in switch statements, for-loops, etc. `Step' continues to stop if a
5151 function that has debugging information is called within the line.
5155 Lots of small bugs fixed. More remain.
5157 * New host supported (not target)
5159 Intel 386 PC clone running Mach i386-none-mach
5162 *** Changes in GDB-4.1:
5164 * Multiple source language support
5166 GDB now has internal scaffolding to handle several source languages.
5167 It determines the type of each source file from its filename extension,
5168 and will switch expression parsing and number formatting to match the
5169 language of the function in the currently selected stack frame.
5170 You can also specifically set the language to be used, with
5171 `set language c' or `set language modula-2'.
5175 GDB now has preliminary support for the GNU Modula-2 compiler,
5176 currently under development at the State University of New York at
5177 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5178 continue through the fall of 1991 and into 1992.
5180 Other Modula-2 compilers are currently not supported, and attempting to
5181 debug programs compiled with them will likely result in an error as the
5182 symbol table is read. Feel free to work on it, though!
5184 There are hooks in GDB for strict type checking and range checking,
5185 in the `Modula-2 philosophy', but they do not currently work.
5189 GDB can now write to executable and core files (e.g. patch
5190 a variable's value). You must turn this switch on, specify
5191 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5192 by assigning a new value to a variable. Modifications take
5195 * Automatic SunOS shared library reading
5197 When you run your program, GDB automatically determines where its
5198 shared libraries (if any) have been loaded, and reads their symbols.
5199 The `share' command is no longer needed. This also works when
5200 examining core files.
5204 You can specify the number of lines that the `list' command shows.
5207 * New machines supported (host and target)
5209 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5210 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5211 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5213 * New hosts supported (not targets)
5215 IBM RT/PC: romp-ibm-aix or rtpc
5217 * New targets supported (not hosts)
5219 AMD 29000 embedded with COFF a29k-none-coff
5220 AMD 29000 embedded with a.out a29k-none-aout
5221 Ultracomputer remote kernel debug a29k-nyu-kern
5223 * New remote interfaces
5229 *** Changes in GDB-4.0:
5233 Wide output is wrapped at good places to make the output more readable.
5235 Gdb now supports cross-debugging from a host machine of one type to a
5236 target machine of another type. Communication with the target system
5237 is over serial lines. The ``target'' command handles connecting to the
5238 remote system; the ``load'' command will download a program into the
5239 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5240 also supports debugging of realtime processes running under VxWorks,
5241 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5242 stub on the target system.
5244 New CPUs supported include the AMD 29000 and Intel 960.
5246 GDB now reads object files and symbol tables via a ``binary file''
5247 library, which allows a single copy of GDB to debug programs of multiple
5248 object file types such as a.out and coff.
5250 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5251 refcard.dvi and refcard.ps are available to format it).
5254 * Control-Variable user interface simplified
5256 All variables that control the operation of the debugger can be set
5257 by the ``set'' command, and displayed by the ``show'' command.
5259 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5260 ``Show prompt'' produces the response:
5261 Gdb's prompt is new-gdb=>.
5263 What follows are the NEW set commands. The command ``help set'' will
5264 print a complete list of old and new set commands. ``help set FOO''
5265 will give a longer description of the variable FOO. ``show'' will show
5266 all of the variable descriptions and their current settings.
5268 confirm on/off: Enables warning questions for operations that are
5269 hard to recover from, e.g. rerunning the program while
5270 it is already running. Default is ON.
5272 editing on/off: Enables EMACS style command line editing
5273 of input. Previous lines can be recalled with
5274 control-P, the current line can be edited with control-B,
5275 you can search for commands with control-R, etc.
5278 history filename NAME: NAME is where the gdb command history
5279 will be stored. The default is .gdb_history,
5280 or the value of the environment variable
5283 history size N: The size, in commands, of the command history. The
5284 default is 256, or the value of the environment variable
5287 history save on/off: If this value is set to ON, the history file will
5288 be saved after exiting gdb. If set to OFF, the
5289 file will not be saved. The default is OFF.
5291 history expansion on/off: If this value is set to ON, then csh-like
5292 history expansion will be performed on
5293 command line input. The default is OFF.
5295 radix N: Sets the default radix for input and output. It can be set
5296 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5297 in the current radix, so "set radix 10" is always a no-op.
5299 height N: This integer value is the number of lines on a page. Default
5300 is 24, the current `stty rows'' setting, or the ``li#''
5301 setting from the termcap entry matching the environment
5304 width N: This integer value is the number of characters on a line.
5305 Default is 80, the current `stty cols'' setting, or the ``co#''
5306 setting from the termcap entry matching the environment
5309 Note: ``set screensize'' is obsolete. Use ``set height'' and
5310 ``set width'' instead.
5312 print address on/off: Print memory addresses in various command displays,
5313 such as stack traces and structure values. Gdb looks
5314 more ``symbolic'' if you turn this off; it looks more
5315 ``machine level'' with it on. Default is ON.
5317 print array on/off: Prettyprint arrays. New convenient format! Default
5320 print demangle on/off: Print C++ symbols in "source" form if on,
5323 print asm-demangle on/off: Same, for assembler level printouts
5326 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5329 * Support for Epoch Environment.
5331 The epoch environment is a version of Emacs v18 with windowing. One
5332 new command, ``inspect'', is identical to ``print'', except that if you
5333 are running in the epoch environment, the value is printed in its own
5337 * Support for Shared Libraries
5339 GDB can now debug programs and core files that use SunOS shared libraries.
5340 Symbols from a shared library cannot be referenced
5341 before the shared library has been linked with the program (this
5342 happens after you type ``run'' and before the function main() is entered).
5343 At any time after this linking (including when examining core files
5344 from dynamically linked programs), gdb reads the symbols from each
5345 shared library when you type the ``sharedlibrary'' command.
5346 It can be abbreviated ``share''.
5348 sharedlibrary REGEXP: Load shared object library symbols for files
5349 matching a unix regular expression. No argument
5350 indicates to load symbols for all shared libraries.
5352 info sharedlibrary: Status of loaded shared libraries.
5357 A watchpoint stops execution of a program whenever the value of an
5358 expression changes. Checking for this slows down execution
5359 tremendously whenever you are in the scope of the expression, but is
5360 quite useful for catching tough ``bit-spreader'' or pointer misuse
5361 problems. Some machines such as the 386 have hardware for doing this
5362 more quickly, and future versions of gdb will use this hardware.
5364 watch EXP: Set a watchpoint (breakpoint) for an expression.
5366 info watchpoints: Information about your watchpoints.
5368 delete N: Deletes watchpoint number N (same as breakpoints).
5369 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5370 enable N: Re-enables watchpoint number N (same as breakpoints).
5373 * C++ multiple inheritance
5375 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5378 * C++ exception handling
5380 Gdb now supports limited C++ exception handling. Besides the existing
5381 ability to breakpoint on an exception handler, gdb can breakpoint on
5382 the raising of an exception (before the stack is peeled back to the
5385 catch FOO: If there is a FOO exception handler in the dynamic scope,
5386 set a breakpoint to catch exceptions which may be raised there.
5387 Multiple exceptions (``catch foo bar baz'') may be caught.
5389 info catch: Lists all exceptions which may be caught in the
5390 current stack frame.
5393 * Minor command changes
5395 The command ``call func (arg, arg, ...)'' now acts like the print
5396 command, except it does not print or save a value if the function's result
5397 is void. This is similar to dbx usage.
5399 The ``up'' and ``down'' commands now always print the frame they end up
5400 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5401 frames without printing.
5403 * New directory command
5405 'dir' now adds directories to the FRONT of the source search path.
5406 The path starts off empty. Source files that contain debug information
5407 about the directory in which they were compiled can be found even
5408 with an empty path; Sun CC and GCC include this information. If GDB can't
5409 find your source file in the current directory, type "dir .".
5411 * Configuring GDB for compilation
5413 For normal use, type ``./configure host''. See README or gdb.texinfo
5416 GDB now handles cross debugging. If you are remotely debugging between
5417 two different machines, type ``./configure host -target=targ''.
5418 Host is the machine where GDB will run; targ is the machine
5419 where the program that you are debugging will run.