1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.6
8 Nios II ELF nios2*-*-elf
9 Nios II GNU/Linux nios2*-*-linux
13 Like "catch throw", but catches a re-thrown exception.
16 Display the details of GDB configure-time options.
18 maint set|show per-command
19 maint set|show per-command space
20 maint set|show per-command time
21 maint set|show per-command symtab
22 Enable display of per-command gdb resource usage.
26 set remote trace-status-packet
27 show remote trace-status-packet
28 Set/show the use of remote protocol qTStatus packet.
32 Control display of debugging messages related to Nios II targets.
34 * You can now use a literal value 'unlimited' for options that
35 interpret 0 or -1 as meaning "unlimited". E.g., "set
36 trace-buffer-size unlimited" is now an alias for "set
37 trace-buffer-size -1" and "set height unlimited" is now an alias for
40 * New command-line options
42 Display the details of GDB configure-time options.
44 * The command 'tsave' can now support new option '-ctf' to save trace
45 buffer in Common Trace Format.
47 * Newly installed $prefix/bin/gcore acts as a shell interface for the
50 * GDB now implements the the C++ 'typeid' operator.
52 * The new convenience variable $_exception holds the exception being
53 thrown or caught at an exception-related catchpoint.
55 * The exception-related catchpoints, like "catch throw", now accept a
56 regular expression which can be used to filter exceptions by type.
60 ** The -trace-save MI command can optionally save trace buffer in Common
63 *** Changes in GDB 7.6
65 * Target record has been renamed to record-full.
66 Record/replay is now enabled with the "record full" command.
67 This also affects settings that are associated with full record/replay
68 that have been moved from "set/show record" to "set/show record full":
70 set|show record full insn-number-max
71 set|show record full stop-at-limit
72 set|show record full memory-query
74 * A new record target "record-btrace" has been added. The new target
75 uses hardware support to record the control-flow of a process. It
76 does not support replaying the execution, but it implements the
77 below new commands for investigating the recorded execution log.
78 This new recording method can be enabled using:
82 The "record-btrace" target is only available on Intel Atom processors
83 and requires a Linux kernel 2.6.32 or later.
85 * Two new commands have been added for record/replay to give information
86 about the recorded execution without having to replay the execution.
87 The commands are only supported by "record btrace".
89 record instruction-history prints the execution history at
90 instruction granularity
92 record function-call-history prints the execution history at
95 * New native configurations
97 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
98 FreeBSD/powerpc powerpc*-*-freebsd
99 x86_64/Cygwin x86_64-*-cygwin*
100 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
104 ARM AArch64 aarch64*-*-elf
105 ARM AArch64 GNU/Linux aarch64*-*-linux
106 Lynx 178 PowerPC powerpc-*-lynx*178
107 x86_64/Cygwin x86_64-*-cygwin*
108 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
110 * If the configured location of system.gdbinit file (as given by the
111 --with-system-gdbinit option at configure time) is in the
112 data-directory (as specified by --with-gdb-datadir at configure
113 time) or in one of its subdirectories, then GDB will look for the
114 system-wide init file in the directory specified by the
115 --data-directory command-line option.
117 * New command line options:
119 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
120 other initialization files, unlike -nx which disables all of them.
122 * Removed command line options
124 -epoch This was used by the gdb mode in Epoch, an ancient fork of
127 * The 'ptype' and 'whatis' commands now accept an argument to control
130 * 'info proc' now works on some core files.
134 ** Vectors can be created with gdb.Type.vector.
136 ** Python's atexit.register now works in GDB.
138 ** Types can be pretty-printed via a Python API.
140 ** Python 3 is now supported (in addition to Python 2.4 or later)
142 ** New class gdb.Architecture exposes GDB's internal representation
143 of architecture in the Python API.
145 ** New method Frame.architecture returns the gdb.Architecture object
146 corresponding to the frame's architecture.
148 * New Python-based convenience functions:
150 ** $_memeq(buf1, buf2, length)
151 ** $_streq(str1, str2)
153 ** $_regex(str, regex)
155 * The 'cd' command now defaults to using '~' (the home directory) if not
158 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
159 default for GCC since November 2000.
161 * The command 'forward-search' can now be abbreviated as 'fo'.
163 * The command 'info tracepoints' can now display 'installed on target'
164 or 'not installed on target' for each non-pending location of tracepoint.
166 * New configure options
168 --enable-libmcheck/--disable-libmcheck
169 By default, development versions are built with -lmcheck on hosts
170 that support it, in order to help track memory corruption issues.
171 Release versions, on the other hand, are built without -lmcheck
172 by default. The --enable-libmcheck/--disable-libmcheck configure
173 options allow the user to override that default.
174 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
175 This configure option allows the user to build GDB with
176 libbabeltrace using which GDB can read Common Trace Format data.
178 * New commands (for set/show, see "New options" below)
181 Catch signals. This is similar to "handle", but allows commands and
182 conditions to be attached.
185 List the BFDs known to GDB.
187 python-interactive [command]
189 Start a Python interactive prompt, or evaluate the optional command
190 and print the result of expressions.
193 "py" is a new alias for "python".
195 enable type-printer [name]...
196 disable type-printer [name]...
197 Enable or disable type printers.
201 ** For the Renesas Super-H architecture, the "regs" command has been removed
202 (has been deprecated in GDB 7.5), and "info all-registers" should be used
207 set print type methods (on|off)
208 show print type methods
209 Control whether method declarations are displayed by "ptype".
210 The default is to show them.
212 set print type typedefs (on|off)
213 show print type typedefs
214 Control whether typedef definitions are displayed by "ptype".
215 The default is to show them.
217 set filename-display basename|relative|absolute
218 show filename-display
219 Control the way in which filenames is displayed.
220 The default is "relative", which preserves previous behavior.
222 set trace-buffer-size
223 show trace-buffer-size
224 Request target to change the size of trace buffer.
226 set remote trace-buffer-size-packet auto|on|off
227 show remote trace-buffer-size-packet
228 Control the use of the remote protocol `QTBuffer:size' packet.
232 Control display of debugging messages related to ARM AArch64.
235 set debug coff-pe-read
236 show debug coff-pe-read
237 Control display of debugging messages related to reading of COFF/PE
242 Control display of debugging messages related to Mach-O symbols
245 set debug notification
246 show debug notification
247 Control display of debugging info for async remote notification.
251 ** Command parameter changes are now notified using new async record
252 "=cmd-param-changed".
253 ** Trace frame changes caused by command "tfind" are now notified using
254 new async record "=traceframe-changed".
255 ** The creation, deletion and modification of trace state variables
256 are now notified using new async records "=tsv-created",
257 "=tsv-deleted" and "=tsv-modified".
258 ** The start and stop of process record are now notified using new
259 async record "=record-started" and "=record-stopped".
260 ** Memory changes are now notified using new async record
262 ** The data-disassemble command response will include a "fullname" field
263 containing the absolute file name when source has been requested.
264 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
265 command, to allow pattern filling of memory areas.
266 ** New commands "-catch-load"/"-catch-unload" added for intercepting
267 library load/unload events.
268 ** The response to breakpoint commands and breakpoint async records
269 includes an "installed" field containing a boolean state about each
270 non-pending tracepoint location is whether installed on target or not.
271 ** Output of the "-trace-status" command includes a "trace-file" field
272 containing the name of the trace file being examined. This field is
273 optional, and only present when examining a trace file.
274 ** The "fullname" field is now always present along with the "file" field,
275 even if the file cannot be found by GDB.
277 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
278 You must have the LZMA library available when configuring GDB for this
279 feature to be enabled. For more information, see:
280 http://fedoraproject.org/wiki/Features/MiniDebugInfo
285 Set the size of trace buffer. The remote stub reports support for this
286 packet to gdb's qSupported query.
289 Enable Branch Trace Store (BTS)-based branch tracing for the current
290 thread. The remote stub reports support for this packet to gdb's
294 Disable branch tracing for the current thread. The remote stub reports
295 support for this packet to gdb's qSupported query.
298 Read the traced branches for the current thread. The remote stub
299 reports support for this packet to gdb's qSupported query.
301 *** Changes in GDB 7.5
303 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
304 for more x32 ABI info.
306 * GDB now supports access to MIPS DSP registers on Linux targets.
308 * GDB now supports debugging microMIPS binaries.
310 * The "info os" command on GNU/Linux can now display information on
311 several new classes of objects managed by the operating system:
312 "info os procgroups" lists process groups
313 "info os files" lists file descriptors
314 "info os sockets" lists internet-domain sockets
315 "info os shm" lists shared-memory regions
316 "info os semaphores" lists semaphores
317 "info os msg" lists message queues
318 "info os modules" lists loaded kernel modules
320 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
321 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
322 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
323 options and inspect the probe arguments using the new $_probe_arg family
324 of convenience variables. You can obtain more information about SystemTap
325 in <http://sourceware.org/systemtap/>.
327 * GDB now supports reversible debugging on ARM, it allows you to
328 debug basic ARM and THUMB instructions, and provides
329 record/replay support.
331 * The option "symbol-reloading" has been deleted as it is no longer used.
335 ** GDB commands implemented in Python can now be put in command class
338 ** The "maint set python print-stack on|off" is now deleted.
340 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
341 apply "flag enum"-style pretty-printing to any enum.
343 ** gdb.lookup_symbol can now work when there is no current frame.
345 ** gdb.Symbol now has a 'line' attribute, holding the line number in
346 the source at which the symbol was defined.
348 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
349 method 'value'. The former indicates whether the symbol needs a
350 frame in order to compute its value, and the latter computes the
353 ** A new method 'referenced_value' on gdb.Value objects which can
354 dereference pointer as well as C++ reference values.
356 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
357 which return the global and static blocks (as gdb.Block objects),
358 of the underlying symbol table, respectively.
360 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
361 object associated with a PC value.
363 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
364 of the address range occupied by code for the current source line.
366 * Go language support.
367 GDB now supports debugging programs written in the Go programming
370 * GDBserver now supports stdio connections.
371 E.g. (gdb) target remote | ssh myhost gdbserver - hello
373 * The binary "gdbtui" can no longer be built or installed.
374 Use "gdb -tui" instead.
376 * GDB will now print "flag" enums specially. A flag enum is one where
377 all the enumerator values have no bits in common when pairwise
378 "and"ed. When printing a value whose type is a flag enum, GDB will
379 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
380 (gdb) print (enum E) 3
383 * The filename part of a linespec will now match trailing components
384 of a source file name. For example, "break gcc/expr.c:1000" will
385 now set a breakpoint in build/gcc/expr.c, but not
388 * The "info proc" and "generate-core-file" commands will now also
389 work on remote targets connected to GDBserver on Linux.
391 * The command "info catch" has been removed. It has been disabled
394 * The "catch exception" and "catch assert" commands now accept
395 a condition at the end of the command, much like the "break"
396 command does. For instance:
398 (gdb) catch exception Constraint_Error if Barrier = True
400 Previously, it was possible to add a condition to such catchpoints,
401 but it had to be done as a second step, after the catchpoint had been
402 created, using the "condition" command.
404 * The "info static-tracepoint-marker" command will now also work on
405 native Linux targets with in-process agent.
407 * GDB can now set breakpoints on inlined functions.
409 * The .gdb_index section has been updated to include symbols for
410 inlined functions. GDB will ignore older .gdb_index sections by
411 default, which could cause symbol files to be loaded more slowly
412 until their .gdb_index sections can be recreated. The new command
413 "set use-deprecated-index-sections on" will cause GDB to use any older
414 .gdb_index sections it finds. This will restore performance, but the
415 ability to set breakpoints on inlined functions will be lost in symbol
416 files with older .gdb_index sections.
418 The .gdb_index section has also been updated to record more information
419 about each symbol. This speeds up the "info variables", "info functions"
420 and "info types" commands when used with programs having the .gdb_index
421 section, as well as speeding up debugging with shared libraries using
422 the .gdb_index section.
424 * Ada support for GDB/MI Variable Objects has been added.
426 * GDB can now support 'breakpoint always-inserted mode' in 'record'
431 ** New command -info-os is the MI equivalent of "info os".
433 ** Output logs ("set logging" and related) now include MI output.
437 ** "set use-deprecated-index-sections on|off"
438 "show use-deprecated-index-sections on|off"
439 Controls the use of deprecated .gdb_index sections.
441 ** "catch load" and "catch unload" can be used to stop when a shared
442 library is loaded or unloaded, respectively.
444 ** "enable count" can be used to auto-disable a breakpoint after
447 ** "info vtbl" can be used to show the virtual method tables for
448 C++ and Java objects.
450 ** "explore" and its sub commands "explore value" and "explore type"
451 can be used to reccursively explore values and types of
452 expressions. These commands are available only if GDB is
453 configured with '--with-python'.
455 ** "info auto-load" shows status of all kinds of auto-loaded files,
456 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
457 sequences of commands files, "info auto-load python-scripts"
458 shows status of auto-loading Python script files,
459 "info auto-load local-gdbinit" shows status of loading init file
460 (.gdbinit) from current directory and "info auto-load libthread-db" shows
461 status of inferior specific thread debugging shared library loading.
463 ** "info auto-load-scripts", "set auto-load-scripts on|off"
464 and "show auto-load-scripts" commands have been deprecated, use their
465 "info auto-load python-scripts", "set auto-load python-scripts on|off"
466 and "show auto-load python-scripts" counterparts instead.
468 ** "dprintf location,format,args..." creates a dynamic printf, which
469 is basically a breakpoint that does a printf and immediately
470 resumes your program's execution, so it is like a printf that you
471 can insert dynamically at runtime instead of at compiletime.
473 ** "set print symbol"
475 Controls whether GDB attempts to display the symbol, if any,
476 corresponding to addresses it prints. This defaults to "on", but
477 you can set it to "off" to restore GDB's previous behavior.
479 * Deprecated commands
481 ** For the Renesas Super-H architecture, the "regs" command has been
482 deprecated, and "info all-registers" should be used instead.
486 Renesas RL78 rl78-*-elf
487 HP OpenVMS ia64 ia64-hp-openvms*
489 * GDBserver supports evaluation of breakpoint conditions. When
490 support is advertised by GDBserver, GDB may be told to send the
491 breakpoint conditions in bytecode form to GDBserver. GDBserver
492 will only report the breakpoint trigger to GDB when its condition
498 show mips compression
499 Select the compressed ISA encoding used in functions that have no symbol
500 information available. The encoding can be set to either of:
503 and is updated automatically from ELF file flags if available.
505 set breakpoint condition-evaluation
506 show breakpoint condition-evaluation
507 Control whether breakpoint conditions are evaluated by GDB ("host") or by
508 GDBserver ("target"). Default option "auto" chooses the most efficient
510 This option can improve debugger efficiency depending on the speed of the
514 Disable auto-loading globally.
517 Show auto-loading setting of all kinds of auto-loaded files.
519 set auto-load gdb-scripts on|off
520 show auto-load gdb-scripts
521 Control auto-loading of GDB canned sequences of commands files.
523 set auto-load python-scripts on|off
524 show auto-load python-scripts
525 Control auto-loading of Python script files.
527 set auto-load local-gdbinit on|off
528 show auto-load local-gdbinit
529 Control loading of init file (.gdbinit) from current directory.
531 set auto-load libthread-db on|off
532 show auto-load libthread-db
533 Control auto-loading of inferior specific thread debugging shared library.
535 set auto-load scripts-directory <dir1>[:<dir2>...]
536 show auto-load scripts-directory
537 Set a list of directories from which to load auto-loaded scripts.
538 Automatically loaded Python scripts and GDB scripts are located in one
539 of the directories listed by this option.
540 The delimiter (':' above) may differ according to the host platform.
542 set auto-load safe-path <dir1>[:<dir2>...]
543 show auto-load safe-path
544 Set a list of directories from which it is safe to auto-load files.
545 The delimiter (':' above) may differ according to the host platform.
547 set debug auto-load on|off
549 Control display of debugging info for auto-loading the files above.
551 set dprintf-style gdb|call|agent
553 Control the way in which a dynamic printf is performed; "gdb"
554 requests a GDB printf command, while "call" causes dprintf to call a
555 function in the inferior. "agent" requests that the target agent
556 (such as GDBserver) do the printing.
558 set dprintf-function <expr>
559 show dprintf-function
560 set dprintf-channel <expr>
562 Set the function and optional first argument to the call when using
563 the "call" style of dynamic printf.
565 set disconnected-dprintf on|off
566 show disconnected-dprintf
567 Control whether agent-style dynamic printfs continue to be in effect
568 after GDB disconnects.
570 * New configure options
573 Configure default value for the 'set auto-load scripts-directory'
574 setting above. It defaults to '$debugdir:$datadir/auto-load',
575 $debugdir representing global debugging info directories (available
576 via 'show debug-file-directory') and $datadir representing GDB's data
577 directory (available via 'show data-directory').
579 --with-auto-load-safe-path
580 Configure default value for the 'set auto-load safe-path' setting
581 above. It defaults to the --with-auto-load-dir setting.
583 --without-auto-load-safe-path
584 Set 'set auto-load safe-path' to '/', effectively disabling this
589 z0/z1 conditional breakpoints extension
591 The z0/z1 breakpoint insertion packets have been extended to carry
592 a list of conditional expressions over to the remote stub depending on the
593 condition evaluation mode. The use of this extension can be controlled
594 via the "set remote conditional-breakpoints-packet" command.
598 Specify the signals which the remote stub may pass to the debugged
599 program without GDB involvement.
601 * New command line options
603 --init-command=FILE, -ix Like --command, -x but execute it
604 before loading inferior.
605 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
606 execute it before loading inferior.
608 *** Changes in GDB 7.4
610 * GDB now handles ambiguous linespecs more consistently; the existing
611 FILE:LINE support has been expanded to other types of linespecs. A
612 breakpoint will now be set on all matching locations in all
613 inferiors, and locations will be added or removed according to
616 * GDB now allows you to skip uninteresting functions and files when
617 stepping with the "skip function" and "skip file" commands.
619 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
620 and "show remote hardware-watchpoint-length-limit". These allows to
621 set or show the maximum length limit (in bytes) of a remote
622 target hardware watchpoint.
624 This allows e.g. to use "unlimited" hardware watchpoints with the
625 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
626 watchpoints are slower than real hardware watchpoints but are
627 significantly faster than gdb software watchpoints.
631 ** The register_pretty_printer function in module gdb.printing now takes
632 an optional `replace' argument. If True, the new printer replaces any
635 ** The "maint set python print-stack on|off" command has been
636 deprecated and will be deleted in GDB 7.5.
637 A new command: "set python print-stack none|full|message" has
638 replaced it. Additionally, the default for "print-stack" is
639 now "message", which just prints the error message without
642 ** A prompt substitution hook (prompt_hook) is now available to the
645 ** A new Python module, gdb.prompt has been added to the GDB Python
646 modules library. This module provides functionality for
647 escape sequences in prompts (used by set/show
648 extended-prompt). These escape sequences are replaced by their
651 ** Python commands and convenience-functions located in
652 'data-directory'/python/gdb/command and
653 'data-directory'/python/gdb/function are now automatically loaded
656 ** Blocks now provide four new attributes. global_block and
657 static_block will return the global and static blocks
658 respectively. is_static and is_global are boolean attributes
659 that indicate if the block is one of those two types.
661 ** Symbols now provide the "type" attribute, the type of the symbol.
663 ** The "gdb.breakpoint" function has been deprecated in favor of
666 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
667 of a function. This class is based on the "finish" command
668 available in the CLI.
670 ** Type objects for struct and union types now allow access to
671 the fields using standard Python dictionary (mapping) methods.
672 For example, "some_type['myfield']" now works, as does
675 ** A new event "gdb.new_objfile" has been added, triggered by loading a
678 ** A new function, "deep_items" has been added to the gdb.types
679 module in the GDB Python modules library. This function returns
680 an iterator over the fields of a struct or union type. Unlike
681 the standard Python "iteritems" method, it will recursively traverse
682 any anonymous fields.
686 ** "*stopped" events can report several new "reason"s, such as
689 ** Breakpoint changes are now notified using new async records, like
690 "=breakpoint-modified".
692 ** New command -ada-task-info.
694 * libthread-db-search-path now supports two special values: $sdir and $pdir.
695 $sdir specifies the default system locations of shared libraries.
696 $pdir specifies the directory where the libpthread used by the application
699 GDB no longer looks in $sdir and $pdir after it has searched the directories
700 mentioned in libthread-db-search-path. If you want to search those
701 directories, they must be specified in libthread-db-search-path.
702 The default value of libthread-db-search-path on GNU/Linux and Solaris
703 systems is now "$sdir:$pdir".
705 $pdir is not supported by gdbserver, it is currently ignored.
706 $sdir is supported by gdbserver.
708 * New configure option --with-iconv-bin.
709 When using the internationalization support like the one in the GNU C
710 library, GDB will invoke the "iconv" program to get a list of supported
711 character sets. If this program lives in a non-standard location, one can
712 use this option to specify where to find it.
714 * When natively debugging programs on PowerPC BookE processors running
715 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
716 watchpoints, which specify a mask in addition to an address to watch.
717 The mask specifies that some bits of an address (the bits which are
718 reset in the mask) should be ignored when matching the address accessed
719 by the inferior against the watchpoint address. See the "PowerPC Embedded"
720 section in the user manual for more details.
722 * The new option --once causes GDBserver to stop listening for connections once
723 the first connection is made. The listening port used by GDBserver will
724 become available after that.
726 * New commands "info macros" and "alias" have been added.
728 * New function parameters suffix @entry specifies value of function parameter
729 at the time the function got called. Entry values are available only since
735 "!" is now an alias of the "shell" command.
736 Note that no space is needed between "!" and SHELL COMMAND.
740 watch EXPRESSION mask MASK_VALUE
741 The watch command now supports the mask argument which allows creation
742 of masked watchpoints, if the current architecture supports this feature.
744 info auto-load-scripts [REGEXP]
745 This command was formerly named "maintenance print section-scripts".
746 It is now generally useful and is no longer a maintenance-only command.
748 info macro [-all] [--] MACRO
749 The info macro command has new options `-all' and `--'. The first for
750 printing all definitions of a macro. The second for explicitly specifying
751 the end of arguments and the beginning of the macro name in case the macro
752 name starts with a hyphen.
754 collect[/s] EXPRESSIONS
755 The tracepoint collect command now takes an optional modifier "/s"
756 that directs it to dereference pointer-to-character types and
757 collect the bytes of memory up to a zero byte. The behavior is
758 similar to what you see when you use the regular print command on a
759 string. An optional integer following the "/s" sets a bound on the
760 number of bytes that will be collected.
763 The trace start command now interprets any supplied arguments as a
764 note to be recorded with the trace run, with an effect similar to
765 setting the variable trace-notes.
768 The trace stop command now interprets any arguments as a note to be
769 mentioned along with the tstatus report that the trace was stopped
770 with a command. The effect is similar to setting the variable
773 * Tracepoints can now be enabled and disabled at any time after a trace
774 experiment has been started using the standard "enable" and "disable"
775 commands. It is now possible to start a trace experiment with no enabled
776 tracepoints; GDB will display a warning, but will allow the experiment to
777 begin, assuming that tracepoints will be enabled as needed while the trace
780 * Fast tracepoints on 32-bit x86-architectures can now be placed at
781 locations with 4-byte instructions, when they were previously
782 limited to locations with instructions of 5 bytes or longer.
786 set debug dwarf2-read
787 show debug dwarf2-read
788 Turns on or off display of debugging messages related to reading
789 DWARF debug info. The default is off.
791 set debug symtab-create
792 show debug symtab-create
793 Turns on or off display of debugging messages related to symbol table
794 creation. The default is off.
798 Set the GDB prompt, and allow escape sequences to be inserted to
799 display miscellaneous information (see 'help set extended-prompt'
800 for the list of sequences). This prompt (and any information
801 accessed through the escape sequences) is updated every time the
804 set print entry-values (both|compact|default|if-needed|no|only|preferred)
805 show print entry-values
806 Set printing of frame argument values at function entry. In some cases
807 GDB can determine the value of function argument which was passed by the
808 function caller, even if the value was modified inside the called function.
810 set debug entry-values
811 show debug entry-values
812 Control display of debugging info for determining frame argument values at
813 function entry and virtual tail call frames.
815 set basenames-may-differ
816 show basenames-may-differ
817 Set whether a source file may have multiple base names.
818 (A "base name" is the name of a file with the directory part removed.
819 Example: The base name of "/home/user/hello.c" is "hello.c".)
820 If set, GDB will canonicalize file names (e.g., expand symlinks)
821 before comparing them. Canonicalization is an expensive operation,
822 but it allows the same file be known by more than one base name.
823 If not set (the default), all source files are assumed to have just
824 one base name, and gdb will do file name comparisons more efficiently.
830 Set a user name and notes for the current and any future trace runs.
831 This is useful for long-running and/or disconnected traces, to
832 inform others (or yourself) as to who is running the trace, supply
833 contact information, or otherwise explain what is going on.
836 show trace-stop-notes
837 Set a note attached to the trace run, that is displayed when the
838 trace has been stopped by a tstop command. This is useful for
839 instance as an explanation, if you are stopping a trace run that was
840 started by someone else.
846 Dynamically enable a tracepoint in a started trace experiment.
850 Dynamically disable a tracepoint in a started trace experiment.
854 Set the user and notes of the trace run.
858 Query the current status of a tracepoint.
862 Query the minimum length of instruction at which a fast tracepoint may
865 * Dcache size (number of lines) and line-size are now runtime-configurable
866 via "set dcache line" and "set dcache line-size" commands.
870 Texas Instruments TMS320C6x tic6x-*-*
874 Renesas RL78 rl78-*-elf
876 *** Changes in GDB 7.3.1
878 * The build failure for NetBSD and OpenBSD targets have now been fixed.
880 *** Changes in GDB 7.3
882 * GDB has a new command: "thread find [REGEXP]".
883 It finds the thread id whose name, target id, or thread extra info
884 matches the given regular expression.
886 * The "catch syscall" command now works on mips*-linux* targets.
888 * The -data-disassemble MI command now supports modes 2 and 3 for
889 dumping the instruction opcodes.
891 * New command line options
893 -data-directory DIR Specify DIR as the "data-directory".
894 This is mostly for testing purposes.
896 * The "maint set python auto-load on|off" command has been renamed to
897 "set auto-load-scripts on|off".
899 * GDB has a new command: "set directories".
900 It is like the "dir" command except that it replaces the
901 source path list instead of augmenting it.
903 * GDB now understands thread names.
905 On GNU/Linux, "info threads" will display the thread name as set by
906 prctl or pthread_setname_np.
908 There is also a new command, "thread name", which can be used to
909 assign a name internally for GDB to display.
912 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
913 has been integrated into GDB.
917 ** The function gdb.Write now accepts an optional keyword 'stream'.
918 This keyword, when provided, will direct the output to either
919 stdout, stderr, or GDB's logging output.
921 ** Parameters can now be be sub-classed in Python, and in particular
922 you may implement the get_set_doc and get_show_doc functions.
923 This improves how Parameter set/show documentation is processed
924 and allows for more dynamic content.
926 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
927 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
928 have an is_valid method.
930 ** Breakpoints can now be sub-classed in Python, and in particular
931 you may implement a 'stop' function that is executed each time
932 the inferior reaches that breakpoint.
934 ** New function gdb.lookup_global_symbol looks up a global symbol.
936 ** GDB values in Python are now callable if the value represents a
937 function. For example, if 'some_value' represents a function that
938 takes two integer parameters and returns a value, you can call
939 that function like so:
941 result = some_value (10,20)
943 ** Module gdb.types has been added.
944 It contains a collection of utilities for working with gdb.Types objects:
945 get_basic_type, has_field, make_enum_dict.
947 ** Module gdb.printing has been added.
948 It contains utilities for writing and registering pretty-printers.
949 New classes: PrettyPrinter, SubPrettyPrinter,
950 RegexpCollectionPrettyPrinter.
951 New function: register_pretty_printer.
953 ** New commands "info pretty-printers", "enable pretty-printer" and
954 "disable pretty-printer" have been added.
956 ** gdb.parameter("directories") is now available.
958 ** New function gdb.newest_frame returns the newest frame in the
961 ** The gdb.InferiorThread class has a new "name" attribute. This
962 holds the thread's name.
964 ** Python Support for Inferior events.
965 Python scripts can add observers to be notified of events
966 occurring in the process being debugged.
967 The following events are currently supported:
968 - gdb.events.cont Continue event.
969 - gdb.events.exited Inferior exited event.
970 - gdb.events.stop Signal received, and Breakpoint hit events.
974 ** GDB now puts template parameters in scope when debugging in an
975 instantiation. For example, if you have:
977 template<int X> int func (void) { return X; }
979 then if you step into func<5>, "print X" will show "5". This
980 feature requires proper debuginfo support from the compiler; it
981 was added to GCC 4.5.
983 ** The motion commands "next", "finish", "until", and "advance" now
984 work better when exceptions are thrown. In particular, GDB will
985 no longer lose control of the inferior; instead, the GDB will
986 stop the inferior at the point at which the exception is caught.
987 This functionality requires a change in the exception handling
988 code that was introduced in GCC 4.5.
990 * GDB now follows GCC's rules on accessing volatile objects when
991 reading or writing target state during expression evaluation.
992 One notable difference to prior behavior is that "print x = 0"
993 no longer generates a read of x; the value of the assignment is
994 now always taken directly from the value being assigned.
996 * GDB now has some support for using labels in the program's source in
997 linespecs. For instance, you can use "advance label" to continue
998 execution to a label.
1000 * GDB now has support for reading and writing a new .gdb_index
1001 section. This section holds a fast index of DWARF debugging
1002 information and can be used to greatly speed up GDB startup and
1003 operation. See the documentation for `save gdb-index' for details.
1005 * The "watch" command now accepts an optional "-location" argument.
1006 When used, this causes GDB to watch the memory referred to by the
1007 expression. Such a watchpoint is never deleted due to it going out
1010 * GDB now supports thread debugging of core dumps on GNU/Linux.
1012 GDB now activates thread debugging using the libthread_db library
1013 when debugging GNU/Linux core dumps, similarly to when debugging
1014 live processes. As a result, when debugging a core dump file, GDB
1015 is now able to display pthread_t ids of threads. For example, "info
1016 threads" shows the same output as when debugging the process when it
1017 was live. In earlier releases, you'd see something like this:
1020 * 1 LWP 6780 main () at main.c:10
1022 While now you see this:
1025 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1027 It is also now possible to inspect TLS variables when debugging core
1030 When debugging a core dump generated on a machine other than the one
1031 used to run GDB, you may need to point GDB at the correct
1032 libthread_db library with the "set libthread-db-search-path"
1033 command. See the user manual for more details on this command.
1035 * When natively debugging programs on PowerPC BookE processors running
1036 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1037 which stop execution of the inferior whenever it executes an instruction
1038 at any address within the specified range. See the "PowerPC Embedded"
1039 section in the user manual for more details.
1041 * New features in the GDB remote stub, GDBserver
1043 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1044 and i686 LynxOS (version 5.x).
1046 ** GDBserver is now supported on Blackfin Linux.
1048 * New native configurations
1050 ia64 HP-UX ia64-*-hpux*
1054 Analog Devices, Inc. Blackfin Processor bfin-*
1056 * Ada task switching is now supported on sparc-elf targets when
1057 debugging a program using the Ravenscar Profile. For more information,
1058 see the "Tasking Support when using the Ravenscar Profile" section
1059 in the GDB user manual.
1061 * Guile support was removed.
1063 * New features in the GNU simulator
1065 ** The --map-info flag lists all known core mappings.
1067 ** CFI flashes may be simulated via the "cfi" device.
1069 *** Changes in GDB 7.2
1071 * Shared library support for remote targets by default
1073 When GDB is configured for a generic, non-OS specific target, like
1074 for example, --target=arm-eabi or one of the many *-*-elf targets,
1075 GDB now queries remote stubs for loaded shared libraries using the
1076 `qXfer:libraries:read' packet. Previously, shared library support
1077 was always disabled for such configurations.
1081 ** Argument Dependent Lookup (ADL)
1083 In C++ ADL lookup directs function search to the namespaces of its
1084 arguments even if the namespace has not been imported.
1094 Here the compiler will search for `foo' in the namespace of 'b'
1095 and find A::foo. GDB now supports this. This construct is commonly
1096 used in the Standard Template Library for operators.
1098 ** Improved User Defined Operator Support
1100 In addition to member operators, GDB now supports lookup of operators
1101 defined in a namespace and imported with a `using' directive, operators
1102 defined in the global scope, operators imported implicitly from an
1103 anonymous namespace, and the ADL operators mentioned in the previous
1105 GDB now also supports proper overload resolution for all the previously
1106 mentioned flavors of operators.
1108 ** static const class members
1110 Printing of static const class members that are initialized in the
1111 class definition has been fixed.
1113 * Windows Thread Information Block access.
1115 On Windows targets, GDB now supports displaying the Windows Thread
1116 Information Block (TIB) structure. This structure is visible either
1117 by using the new command `info w32 thread-information-block' or, by
1118 dereferencing the new convenience variable named `$_tlb', a
1119 thread-specific pointer to the TIB. This feature is also supported
1120 when remote debugging using GDBserver.
1122 * Static tracepoints
1124 Static tracepoints are calls in the user program into a tracing
1125 library. One such library is a port of the LTTng kernel tracer to
1126 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1127 When debugging with GDBserver, GDB now supports combining the GDB
1128 tracepoint machinery with such libraries. For example: the user can
1129 use GDB to probe a static tracepoint marker (a call from the user
1130 program into the tracing library) with the new "strace" command (see
1131 "New commands" below). This creates a "static tracepoint" in the
1132 breakpoint list, that can be manipulated with the same feature set
1133 as fast and regular tracepoints. E.g., collect registers, local and
1134 global variables, collect trace state variables, and define
1135 tracepoint conditions. In addition, the user can collect extra
1136 static tracepoint marker specific data, by collecting the new
1137 $_sdata internal variable. When analyzing the trace buffer, you can
1138 inspect $_sdata like any other variable available to GDB. For more
1139 information, see the "Tracepoints" chapter in GDB user manual. New
1140 remote packets have been defined to support static tracepoints, see
1141 the "New remote packets" section below.
1143 * Better reconstruction of tracepoints after disconnected tracing
1145 GDB will attempt to download the original source form of tracepoint
1146 definitions when starting a trace run, and then will upload these
1147 upon reconnection to the target, resulting in a more accurate
1148 reconstruction of the tracepoints that are in use on the target.
1152 You can now exercise direct control over the ways that GDB can
1153 affect your program. For instance, you can disallow the setting of
1154 breakpoints, so that the program can run continuously (assuming
1155 non-stop mode). In addition, the "observer" variable is available
1156 to switch all of the different controls; in observer mode, GDB
1157 cannot affect the target's behavior at all, which is useful for
1158 tasks like diagnosing live systems in the field.
1160 * The new convenience variable $_thread holds the number of the
1163 * New remote packets
1167 Return the address of the Windows Thread Information Block of a given thread.
1171 In response to several of the tracepoint packets, the target may now
1172 also respond with a number of intermediate `qRelocInsn' request
1173 packets before the final result packet, to have GDB handle
1174 relocating an instruction to execute at a different address. This
1175 is particularly useful for stubs that support fast tracepoints. GDB
1176 reports support for this feature in the qSupported packet.
1180 List static tracepoint markers in the target program.
1184 List static tracepoint markers at a given address in the target
1187 qXfer:statictrace:read
1189 Read the static trace data collected (by a `collect $_sdata'
1190 tracepoint action). The remote stub reports support for this packet
1191 to gdb's qSupported query.
1195 Send the current settings of GDB's permission flags.
1199 Send part of the source (textual) form of a tracepoint definition,
1200 which includes location, conditional, and action list.
1202 * The source command now accepts a -s option to force searching for the
1203 script in the source search path even if the script name specifies
1206 * New features in the GDB remote stub, GDBserver
1208 - GDBserver now support tracepoints (including fast tracepoints, and
1209 static tracepoints). The feature is currently supported by the
1210 i386-linux and amd64-linux builds. See the "Tracepoints support
1211 in gdbserver" section in the manual for more information.
1213 GDBserver JIT compiles the tracepoint's conditional agent
1214 expression bytecode into native code whenever possible for low
1215 overhead dynamic tracepoints conditionals. For such tracepoints,
1216 an expression that examines program state is evaluated when the
1217 tracepoint is reached, in order to determine whether to capture
1218 trace data. If the condition is simple and false, processing the
1219 tracepoint finishes very quickly and no data is gathered.
1221 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1222 for static tracepoints support.
1224 - GDBserver now supports x86_64 Windows 64-bit debugging.
1226 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1227 it understands register description.
1229 * The --batch flag now disables pagination and queries.
1231 * X86 general purpose registers
1233 GDB now supports reading/writing byte, word and double-word x86
1234 general purpose registers directly. This means you can use, say,
1235 $ah or $ax to refer, respectively, to the byte register AH and
1236 16-bit word register AX that are actually portions of the 32-bit
1237 register EAX or 64-bit register RAX.
1239 * The `commands' command now accepts a range of breakpoints to modify.
1240 A plain `commands' following a command that creates multiple
1241 breakpoints affects all the breakpoints set by that command. This
1242 applies to breakpoints set by `rbreak', and also applies when a
1243 single `break' command creates multiple breakpoints (e.g.,
1244 breakpoints on overloaded c++ functions).
1246 * The `rbreak' command now accepts a filename specification as part of
1247 its argument, limiting the functions selected by the regex to those
1248 in the specified file.
1250 * Support for remote debugging Windows and SymbianOS shared libraries
1251 from Unix hosts has been improved. Non Windows GDB builds now can
1252 understand target reported file names that follow MS-DOS based file
1253 system semantics, such as file names that include drive letters and
1254 use the backslash character as directory separator. This makes it
1255 possible to transparently use the "set sysroot" and "set
1256 solib-search-path" on Unix hosts to point as host copies of the
1257 target's shared libraries. See the new command "set
1258 target-file-system-kind" described below, and the "Commands to
1259 specify files" section in the user manual for more information.
1263 eval template, expressions...
1264 Convert the values of one or more expressions under the control
1265 of the string template to a command line, and call it.
1267 set target-file-system-kind unix|dos-based|auto
1268 show target-file-system-kind
1269 Set or show the assumed file system kind for target reported file
1272 save breakpoints <filename>
1273 Save all current breakpoint definitions to a file suitable for use
1274 in a later debugging session. To read the saved breakpoint
1275 definitions, use the `source' command.
1277 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1280 info static-tracepoint-markers
1281 Display information about static tracepoint markers in the target.
1283 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1284 Define a static tracepoint by probing a marker at the given
1285 function, line, address, or marker ID.
1289 Enable and disable observer mode.
1291 set may-write-registers on|off
1292 set may-write-memory on|off
1293 set may-insert-breakpoints on|off
1294 set may-insert-tracepoints on|off
1295 set may-insert-fast-tracepoints on|off
1296 set may-interrupt on|off
1297 Set individual permissions for GDB effects on the target. Note that
1298 some of these settings can have undesirable or surprising
1299 consequences, particularly when changed in the middle of a session.
1300 For instance, disabling the writing of memory can prevent
1301 breakpoints from being inserted, cause single-stepping to fail, or
1302 even crash your program, if you disable after breakpoints have been
1303 inserted. However, GDB should not crash.
1305 set record memory-query on|off
1306 show record memory-query
1307 Control whether to stop the inferior if memory changes caused
1308 by an instruction cannot be recorded.
1313 The disassemble command now supports "start,+length" form of two arguments.
1317 ** GDB now provides a new directory location, called the python directory,
1318 where Python scripts written for GDB can be installed. The location
1319 of that directory is <data-directory>/python, where <data-directory>
1320 is the GDB data directory. For more details, see section `Scripting
1321 GDB using Python' in the manual.
1323 ** The GDB Python API now has access to breakpoints, symbols, symbol
1324 tables, program spaces, inferiors, threads and frame's code blocks.
1325 Additionally, GDB Parameters can now be created from the API, and
1326 manipulated via set/show in the CLI.
1328 ** New functions gdb.target_charset, gdb.target_wide_charset,
1329 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1331 ** New exception gdb.GdbError.
1333 ** Pretty-printers are now also looked up in the current program space.
1335 ** Pretty-printers can now be individually enabled and disabled.
1337 ** GDB now looks for names of Python scripts to auto-load in a
1338 special section named `.debug_gdb_scripts', in addition to looking
1339 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1341 * Tracepoint actions were unified with breakpoint commands. In particular,
1342 there are no longer differences in "info break" output for breakpoints and
1343 tracepoints and the "commands" command can be used for both tracepoints and
1344 regular breakpoints.
1348 ARM Symbian arm*-*-symbianelf*
1350 * D language support.
1351 GDB now supports debugging programs written in the D programming
1354 * GDB now supports the extended ptrace interface for PowerPC which is
1355 available since Linux kernel version 2.6.34. This automatically enables
1356 any hardware breakpoints and additional hardware watchpoints available in
1357 the processor. The old ptrace interface exposes just one hardware
1358 watchpoint and no hardware breakpoints.
1360 * GDB is now able to use the Data Value Compare (DVC) register available on
1361 embedded PowerPC processors to implement in hardware simple watchpoint
1362 conditions of the form:
1364 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1366 This works in native GDB running on Linux kernels with the extended ptrace
1367 interface mentioned above.
1369 *** Changes in GDB 7.1
1373 ** Namespace Support
1375 GDB now supports importing of namespaces in C++. This enables the
1376 user to inspect variables from imported namespaces. Support for
1377 namepace aliasing has also been added. So, if a namespace is
1378 aliased in the current scope (e.g. namepace C=A; ) the user can
1379 print variables using the alias (e.g. (gdb) print C::x).
1383 All known bugs relating to the printing of virtual base class were
1384 fixed. It is now possible to call overloaded static methods using a
1389 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1390 and reinterpret_cast<> are now handled by the C++ expression parser.
1394 Xilinx MicroBlaze microblaze-*-*
1399 Xilinx MicroBlaze microblaze
1402 * Multi-program debugging.
1404 GDB now has support for multi-program (a.k.a. multi-executable or
1405 multi-exec) debugging. This allows for debugging multiple inferiors
1406 simultaneously each running a different program under the same GDB
1407 session. See "Debugging Multiple Inferiors and Programs" in the
1408 manual for more information. This implied some user visible changes
1409 in the multi-inferior support. For example, "info inferiors" now
1410 lists inferiors that are not running yet or that have exited
1411 already. See also "New commands" and "New options" below.
1413 * New tracing features
1415 GDB's tracepoint facility now includes several new features:
1417 ** Trace state variables
1419 GDB tracepoints now include support for trace state variables, which
1420 are variables managed by the target agent during a tracing
1421 experiment. They are useful for tracepoints that trigger each
1422 other, so for instance one tracepoint can count hits in a variable,
1423 and then a second tracepoint has a condition that is true when the
1424 count reaches a particular value. Trace state variables share the
1425 $-syntax of GDB convenience variables, and can appear in both
1426 tracepoint actions and condition expressions. Use the "tvariable"
1427 command to create, and "info tvariables" to view; see "Trace State
1428 Variables" in the manual for more detail.
1432 GDB now includes an option for defining fast tracepoints, which
1433 targets may implement more efficiently, such as by installing a jump
1434 into the target agent rather than a trap instruction. The resulting
1435 speedup can be by two orders of magnitude or more, although the
1436 tradeoff is that some program locations on some target architectures
1437 might not allow fast tracepoint installation, for instance if the
1438 instruction to be replaced is shorter than the jump. To request a
1439 fast tracepoint, use the "ftrace" command, with syntax identical to
1440 the regular trace command.
1442 ** Disconnected tracing
1444 It is now possible to detach GDB from the target while it is running
1445 a trace experiment, then reconnect later to see how the experiment
1446 is going. In addition, a new variable disconnected-tracing lets you
1447 tell the target agent whether to continue running a trace if the
1448 connection is lost unexpectedly.
1452 GDB now has the ability to save the trace buffer into a file, and
1453 then use that file as a target, similarly to you can do with
1454 corefiles. You can select trace frames, print data that was
1455 collected in them, and use tstatus to display the state of the
1456 tracing run at the moment that it was saved. To create a trace
1457 file, use "tsave <filename>", and to use it, do "target tfile
1460 ** Circular trace buffer
1462 You can ask the target agent to handle the trace buffer as a
1463 circular buffer, discarding the oldest trace frames to make room for
1464 newer ones, by setting circular-trace-buffer to on. This feature may
1465 not be available for all target agents.
1470 The disassemble command, when invoked with two arguments, now requires
1471 the arguments to be comma-separated.
1474 The info variables command now displays variable definitions. Files
1475 which only declare a variable are not shown.
1478 The source command is now capable of sourcing Python scripts.
1479 This feature is dependent on the debugger being build with Python
1482 Related to this enhancement is also the introduction of a new command
1483 "set script-extension" (see below).
1485 * New commands (for set/show, see "New options" below)
1487 record save [<FILENAME>]
1488 Save a file (in core file format) containing the process record
1489 execution log for replay debugging at a later time.
1491 record restore <FILENAME>
1492 Restore the process record execution log that was saved at an
1493 earlier time, for replay debugging.
1495 add-inferior [-copies <N>] [-exec <FILENAME>]
1498 clone-inferior [-copies <N>] [ID]
1499 Make a new inferior ready to execute the same program another
1500 inferior has loaded.
1505 maint info program-spaces
1506 List the program spaces loaded into GDB.
1508 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1509 show remote interrupt-sequence
1510 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1511 as the sequence to the remote target in order to interrupt the execution.
1512 Ctrl-C is a default. Some system prefers BREAK which is high level of
1513 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1514 Magic SysRq g. It is BREAK signal and character 'g'.
1516 set remote interrupt-on-connect [on | off]
1517 show remote interrupt-on-connect
1518 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1519 remote target when gdb connects to it. This is needed when you debug
1522 set remotebreak [on | off]
1524 Deprecated. Use "set/show remote interrupt-sequence" instead.
1526 tvariable $NAME [ = EXP ]
1527 Create or modify a trace state variable.
1530 List trace state variables and their values.
1532 delete tvariable $NAME ...
1533 Delete one or more trace state variables.
1536 Evaluate the given expressions without collecting anything into the
1537 trace buffer. (Valid in tracepoint actions only.)
1539 ftrace FN / FILE:LINE / *ADDR
1540 Define a fast tracepoint at the given function, line, or address.
1542 * New expression syntax
1544 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1545 GDB now parses 0b101010 identically with 42.
1549 set follow-exec-mode new|same
1550 show follow-exec-mode
1551 Control whether GDB reuses the same inferior across an exec call or
1552 creates a new one. This is useful to be able to restart the old
1553 executable after the inferior having done an exec call.
1555 set default-collect EXPR, ...
1556 show default-collect
1557 Define a list of expressions to be collected at each tracepoint.
1558 This is a useful way to ensure essential items are not overlooked,
1559 such as registers or a critical global variable.
1561 set disconnected-tracing
1562 show disconnected-tracing
1563 If set to 1, the target is instructed to continue tracing if it
1564 loses its connection to GDB. If 0, the target is to stop tracing
1567 set circular-trace-buffer
1568 show circular-trace-buffer
1569 If set to on, the target is instructed to use a circular trace buffer
1570 and discard the oldest trace frames instead of stopping the trace due
1571 to a full trace buffer. If set to off, the trace stops when the buffer
1572 fills up. Some targets may not support this.
1574 set script-extension off|soft|strict
1575 show script-extension
1576 If set to "off", the debugger does not perform any script language
1577 recognition, and all sourced files are assumed to be GDB scripts.
1578 If set to "soft" (the default), files are sourced according to
1579 filename extension, falling back to GDB scripts if the first
1581 If set to "strict", files are sourced according to filename extension.
1583 set ada trust-PAD-over-XVS on|off
1584 show ada trust-PAD-over-XVS
1585 If off, activate a workaround against a bug in the debugging information
1586 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1587 the GCC sources for more information about the GNAT encoding and
1588 PAD types in particular). It is always safe to set this option to
1589 off, but this introduces a slight performance penalty. The default
1592 * Python API Improvements
1594 ** GDB provides the new class gdb.LazyString. This is useful in
1595 some pretty-printing cases. The new method gdb.Value.lazy_string
1596 provides a simple way to create objects of this type.
1598 ** The fields returned by gdb.Type.fields now have an
1599 `is_base_class' attribute.
1601 ** The new method gdb.Type.range returns the range of an array type.
1603 ** The new method gdb.parse_and_eval can be used to parse and
1604 evaluate an expression.
1606 * New remote packets
1609 Define a trace state variable.
1612 Get the current value of a trace state variable.
1615 Set desired tracing behavior upon disconnection.
1618 Set the trace buffer to be linear or circular.
1621 Get data about the tracepoints currently in use.
1625 Process record now works correctly with hardware watchpoints.
1627 Multiple bug fixes have been made to the mips-irix port, making it
1628 much more reliable. In particular:
1629 - Debugging threaded applications is now possible again. Previously,
1630 GDB would hang while starting the program, or while waiting for
1631 the program to stop at a breakpoint.
1632 - Attaching to a running process no longer hangs.
1633 - An error occurring while loading a core file has been fixed.
1634 - Changing the value of the PC register now works again. This fixes
1635 problems observed when using the "jump" command, or when calling
1636 a function from GDB, or even when assigning a new value to $pc.
1637 - With the "finish" and "return" commands, the return value for functions
1638 returning a small array is now correctly printed.
1639 - It is now possible to break on shared library code which gets executed
1640 during a shared library init phase (code executed while executing
1641 their .init section). Previously, the breakpoint would have no effect.
1642 - GDB is now able to backtrace through the signal handler for
1643 non-threaded programs.
1645 PIE (Position Independent Executable) programs debugging is now supported.
1646 This includes debugging execution of PIC (Position Independent Code) shared
1647 libraries although for that, it should be possible to run such libraries as an
1650 *** Changes in GDB 7.0
1652 * GDB now has an interface for JIT compilation. Applications that
1653 dynamically generate code can create symbol files in memory and register
1654 them with GDB. For users, the feature should work transparently, and
1655 for JIT developers, the interface is documented in the GDB manual in the
1656 "JIT Compilation Interface" chapter.
1658 * Tracepoints may now be conditional. The syntax is as for
1659 breakpoints; either an "if" clause appended to the "trace" command,
1660 or the "condition" command is available. GDB sends the condition to
1661 the target for evaluation using the same bytecode format as is used
1662 for tracepoint actions.
1664 * The disassemble command now supports: an optional /r modifier, print the
1665 raw instructions in hex as well as in symbolic form, and an optional /m
1666 modifier to print mixed source+assembly.
1668 * Process record and replay
1670 In a architecture environment that supports ``process record and
1671 replay'', ``process record and replay'' target can record a log of
1672 the process execution, and replay it with both forward and reverse
1675 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1676 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1677 set execution-direction {forward|reverse}, for targets that support
1680 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1681 feature is available with a native GDB running on kernel version
1684 * GDB now has support for multi-byte and wide character sets on the
1685 target. Strings whose character type is wchar_t, char16_t, or
1686 char32_t are now correctly printed. GDB supports wide- and unicode-
1687 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1688 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1689 `printf'. This feature requires iconv to work properly; if your
1690 system does not have a working iconv, GDB can use GNU libiconv. See
1691 the installation instructions for more information.
1693 * GDB now supports automatic retrieval of shared library files from
1694 remote targets. To use this feature, specify a system root that begins
1695 with the `remote:' prefix, either via the `set sysroot' command or via
1696 the `--with-sysroot' configure-time option.
1698 * "info sharedlibrary" now takes an optional regex of libraries to show,
1699 and it now reports if a shared library has no debugging information.
1701 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1702 now complete on file names.
1704 * When completing in expressions, gdb will attempt to limit
1705 completions to allowable structure or union fields, where appropriate.
1706 For instance, consider:
1708 # struct example { int f1; double f2; };
1709 # struct example variable;
1712 If the user types TAB at the end of this command line, the available
1713 completions will be "f1" and "f2".
1715 * Inlined functions are now supported. They show up in backtraces, and
1716 the "step", "next", and "finish" commands handle them automatically.
1718 * GDB now supports the token-splicing (##) and stringification (#)
1719 operators when expanding macros. It also supports variable-arity
1722 * GDB now supports inspecting extra signal information, exported by
1723 the new $_siginfo convenience variable. The feature is currently
1724 implemented on linux ARM, i386 and amd64.
1726 * GDB can now display the VFP floating point registers and NEON vector
1727 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1728 can provide these registers (requires Linux 2.6.30 or later). Remote
1729 and simulator targets may also provide them.
1731 * New remote packets
1734 Search memory for a sequence of bytes.
1737 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1738 operation over reliable transport links. Use of this packet is
1739 controlled by the `set remote noack-packet' command.
1742 Kill the process with the specified process ID. Use this in preference
1743 to `k' when multiprocess protocol extensions are supported.
1746 Obtains additional operating system information
1750 Read or write additional signal information.
1752 * Removed remote protocol undocumented extension
1754 An undocumented extension to the remote protocol's `S' stop reply
1755 packet that permited the stub to pass a process id was removed.
1756 Remote servers should use the `T' stop reply packet instead.
1758 * GDB now supports multiple function calling conventions according to the
1759 DWARF-2 DW_AT_calling_convention function attribute.
1761 * The SH target utilizes the aforementioned change to distinguish between gcc
1762 and Renesas calling convention. It also adds the new CLI commands
1763 `set/show sh calling-convention'.
1765 * GDB can now read compressed debug sections, as produced by GNU gold
1766 with the --compress-debug-sections=zlib flag.
1768 * 64-bit core files are now supported on AIX.
1770 * Thread switching is now supported on Tru64.
1772 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1773 which will be allocated using malloc later in program execution.
1775 * The qXfer:libraries:read remote procotol packet now allows passing a
1776 list of section offsets.
1778 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1779 conditions handling signals delivered during attach or thread creation
1780 have also been fixed.
1782 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1783 From the user's standpoint, all unqualified instances of True and False
1784 are treated as the standard definitions, regardless of context.
1786 * GDB now parses C++ symbol and type names more flexibly. For
1789 template<typename T> class C { };
1792 GDB will now correctly handle all of:
1794 ptype C<char const *>
1795 ptype C<char const*>
1796 ptype C<const char *>
1797 ptype C<const char*>
1799 * New features in the GDB remote stub, gdbserver
1801 - The "--wrapper" command-line argument tells gdbserver to use a
1802 wrapper program to launch programs for debugging.
1804 - On PowerPC and S/390 targets, it is now possible to use a single
1805 gdbserver executable to debug both 32-bit and 64-bit programs.
1806 (This requires gdbserver itself to be built as a 64-bit executable.)
1808 - gdbserver uses the new noack protocol mode for TCP connections to
1809 reduce communications latency, if also supported and enabled in GDB.
1811 - Support for the sparc64-linux-gnu target is now included in
1814 - The amd64-linux build of gdbserver now supports debugging both
1815 32-bit and 64-bit programs.
1817 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1818 now support hardware watchpoints, and will use them automatically
1823 GDB now has support for scripting using Python. Whether this is
1824 available is determined at configure time.
1826 New GDB commands can now be written in Python.
1828 * Ada tasking support
1830 Ada tasks can now be inspected in GDB. The following commands have
1834 Print the list of Ada tasks.
1836 Print detailed information about task number N.
1838 Print the task number of the current task.
1840 Switch the context of debugging to task number N.
1842 * Support for user-defined prefixed commands. The "define" command can
1843 add new commands to existing prefixes, e.g. "target".
1845 * Multi-inferior, multi-process debugging.
1847 GDB now has generalized support for multi-inferior debugging. See
1848 "Debugging Multiple Inferiors" in the manual for more information.
1849 Although availability still depends on target support, the command
1850 set is more uniform now. The GNU/Linux specific multi-forks support
1851 has been migrated to this new framework. This implied some user
1852 visible changes; see "New commands" and also "Removed commands"
1855 * Target descriptions can now describe the target OS ABI. See the
1856 "Target Description Format" section in the user manual for more
1859 * Target descriptions can now describe "compatible" architectures
1860 to indicate that the target can execute applications for a different
1861 architecture in addition to those for the main target architecture.
1862 See the "Target Description Format" section in the user manual for
1865 * Multi-architecture debugging.
1867 GDB now includes general supports for debugging applications on
1868 hybrid systems that use more than one single processor architecture
1869 at the same time. Each such hybrid architecture still requires
1870 specific support to be added. The only hybrid architecture supported
1871 in this version of GDB is the Cell Broadband Engine.
1873 * GDB now supports integrated debugging of Cell/B.E. applications that
1874 use both the PPU and SPU architectures. To enable support for hybrid
1875 Cell/B.E. debugging, you need to configure GDB to support both the
1876 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1877 --enable-targets configure option.
1879 * Non-stop mode debugging.
1881 For some targets, GDB now supports an optional mode of operation in
1882 which you can examine stopped threads while other threads continue
1883 to execute freely. This is referred to as non-stop mode, with the
1884 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1885 section in the user manual for more information.
1887 To be able to support remote non-stop debugging, a remote stub needs
1888 to implement the non-stop mode remote protocol extensions, as
1889 described in the "Remote Non-Stop" section of the user manual. The
1890 GDB remote stub, gdbserver, has been adjusted to support these
1891 extensions on linux targets.
1893 * New commands (for set/show, see "New options" below)
1895 catch syscall [NAME(S) | NUMBER(S)]
1896 Catch system calls. Arguments, which should be names of system
1897 calls or their numbers, mean catch only those syscalls. Without
1898 arguments, every syscall will be caught. When the inferior issues
1899 any of the specified syscalls, GDB will stop and announce the system
1900 call, both when it is called and when its call returns. This
1901 feature is currently available with a native GDB running on the
1902 Linux Kernel, under the following architectures: x86, x86_64,
1903 PowerPC and PowerPC64.
1905 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1907 Search memory for a sequence of bytes.
1909 maint set python print-stack
1910 maint show python print-stack
1911 Show a stack trace when an error is encountered in a Python script.
1914 Invoke CODE by passing it to the Python interpreter.
1919 These allow macros to be defined, undefined, and listed
1923 Show operating system information about processes.
1926 List the inferiors currently under GDB's control.
1929 Switch focus to inferior number NUM.
1932 Detach from inferior number NUM.
1935 Kill inferior number NUM.
1939 set spu stop-on-load
1940 show spu stop-on-load
1941 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1943 set spu auto-flush-cache
1944 show spu auto-flush-cache
1945 Control whether to automatically flush the software-managed cache
1946 during Cell/B.E. debugging.
1948 set sh calling-convention
1949 show sh calling-convention
1950 Control the calling convention used when calling SH target functions.
1953 show debug timestamp
1954 Control display of timestamps with GDB debugging output.
1956 set disassemble-next-line
1957 show disassemble-next-line
1958 Control display of disassembled source lines or instructions when
1961 set remote noack-packet
1962 show remote noack-packet
1963 Set/show the use of remote protocol QStartNoAckMode packet. See above
1964 under "New remote packets."
1966 set remote query-attached-packet
1967 show remote query-attached-packet
1968 Control use of remote protocol `qAttached' (query-attached) packet.
1970 set remote read-siginfo-object
1971 show remote read-siginfo-object
1972 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1975 set remote write-siginfo-object
1976 show remote write-siginfo-object
1977 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1980 set remote reverse-continue
1981 show remote reverse-continue
1982 Control use of remote protocol 'bc' (reverse-continue) packet.
1984 set remote reverse-step
1985 show remote reverse-step
1986 Control use of remote protocol 'bs' (reverse-step) packet.
1988 set displaced-stepping
1989 show displaced-stepping
1990 Control displaced stepping mode. Displaced stepping is a way to
1991 single-step over breakpoints without removing them from the debuggee.
1992 Also known as "out-of-line single-stepping".
1995 show debug displaced
1996 Control display of debugging info for displaced stepping.
1998 maint set internal-error
1999 maint show internal-error
2000 Control what GDB does when an internal error is detected.
2002 maint set internal-warning
2003 maint show internal-warning
2004 Control what GDB does when an internal warning is detected.
2009 Use a wrapper program to launch programs for debugging.
2011 set multiple-symbols (all|ask|cancel)
2012 show multiple-symbols
2013 The value of this variable can be changed to adjust the debugger behavior
2014 when an expression or a breakpoint location contains an ambiguous symbol
2015 name (an overloaded function name, for instance).
2017 set breakpoint always-inserted
2018 show breakpoint always-inserted
2019 Keep breakpoints always inserted in the target, as opposed to inserting
2020 them when resuming the target, and removing them when the target stops.
2021 This option can improve debugger performance on slow remote targets.
2023 set arm fallback-mode (arm|thumb|auto)
2024 show arm fallback-mode
2025 set arm force-mode (arm|thumb|auto)
2027 These commands control how ARM GDB determines whether instructions
2028 are ARM or Thumb. The default for both settings is auto, which uses
2029 the current CPSR value for instructions without symbols; previous
2030 versions of GDB behaved as if "set arm fallback-mode arm".
2032 set disable-randomization
2033 show disable-randomization
2034 Standalone programs run with the virtual address space randomization enabled
2035 by default on some platforms. This option keeps the addresses stable across
2036 multiple debugging sessions.
2040 Control whether other threads are stopped or not when some thread hits
2045 Requests that asynchronous execution is enabled in the target, if available.
2046 In this case, it's possible to resume target in the background, and interact
2047 with GDB while the target is running. "show target-async" displays the
2048 current state of asynchronous execution of the target.
2050 set target-wide-charset
2051 show target-wide-charset
2052 The target-wide-charset is the name of the character set that GDB
2053 uses when printing characters whose type is wchar_t.
2055 set tcp auto-retry (on|off)
2057 set tcp connect-timeout
2058 show tcp connect-timeout
2059 These commands allow GDB to retry failed TCP connections to a remote stub
2060 with a specified timeout period; this is useful if the stub is launched
2061 in parallel with GDB but may not be ready to accept connections immediately.
2063 set libthread-db-search-path
2064 show libthread-db-search-path
2065 Control list of directories which GDB will search for appropriate
2068 set schedule-multiple (on|off)
2069 show schedule-multiple
2070 Allow GDB to resume all threads of all processes or only threads of
2071 the current process.
2075 Use more aggressive caching for accesses to the stack. This improves
2076 performance of remote debugging (particularly backtraces) without
2077 affecting correctness.
2079 set interactive-mode (on|off|auto)
2080 show interactive-mode
2081 Control whether GDB runs in interactive mode (on) or not (off).
2082 When in interactive mode, GDB waits for the user to answer all
2083 queries. Otherwise, GDB does not wait and assumes the default
2084 answer. When set to auto (the default), GDB determines which
2085 mode to use based on the stdin settings.
2090 For program forks, this is replaced by the new more generic `info
2091 inferiors' command. To list checkpoints, you can still use the
2092 `info checkpoints' command, which was an alias for the `info forks'
2096 Replaced by the new `inferior' command. To switch between
2097 checkpoints, you can still use the `restart' command, which was an
2098 alias for the `fork' command.
2101 This is removed, since some targets don't have a notion of
2102 processes. To switch between processes, you can still use the
2103 `inferior' command using GDB's own inferior number.
2106 For program forks, this is replaced by the new more generic `kill
2107 inferior' command. To delete a checkpoint, you can still use the
2108 `delete checkpoint' command, which was an alias for the `delete
2112 For program forks, this is replaced by the new more generic `detach
2113 inferior' command. To detach a checkpoint, you can still use the
2114 `detach checkpoint' command, which was an alias for the `detach
2117 * New native configurations
2119 x86/x86_64 Darwin i[34567]86-*-darwin*
2121 x86_64 MinGW x86_64-*-mingw*
2125 Lattice Mico32 lm32-*
2126 x86 DICOS i[34567]86-*-dicos*
2127 x86_64 DICOS x86_64-*-dicos*
2130 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2131 (mingw32ce) debugging.
2137 These commands were actually not implemented on any target.
2139 *** Changes in GDB 6.8
2141 * New native configurations
2143 NetBSD/hppa hppa*-*netbsd*
2144 Xtensa GNU/Linux xtensa*-*-linux*
2148 NetBSD/hppa hppa*-*-netbsd*
2149 Xtensa GNU/Lunux xtensa*-*-linux*
2151 * Change in command line behavior -- corefiles vs. process ids.
2153 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2154 attaching to process NUMBER fails, GDB no longer attempts to open a
2155 core file named NUMBER. Attaching to a program using the -c option
2156 is no longer supported. Instead, use the '-p' or '--pid' options.
2158 * GDB can now be built as a native debugger for debugging Windows x86
2159 (mingw32) Portable Executable (PE) programs.
2161 * Pending breakpoints no longer change their number when their address
2164 * GDB now supports breakpoints with multiple locations,
2165 including breakpoints on C++ constructors, inside C++ templates,
2166 and in inlined functions.
2168 * GDB's ability to debug optimized code has been improved. GDB more
2169 accurately identifies function bodies and lexical blocks that occupy
2170 more than one contiguous range of addresses.
2172 * Target descriptions can now describe registers for PowerPC.
2174 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2175 registers on PowerPC targets.
2177 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2178 targets even when the libthread_db library is not available.
2180 * The GDB remote stub, gdbserver, now supports the new file transfer
2181 commands (remote put, remote get, and remote delete).
2183 * The GDB remote stub, gdbserver, now supports run and attach in
2184 extended-remote mode.
2186 * hppa*64*-*-hpux11* target broken
2187 The debugger is unable to start a program and fails with the following
2188 error: "Error trying to get information about dynamic linker".
2189 The gdb-6.7 release is also affected.
2191 * GDB now supports the --enable-targets= configure option to allow
2192 building a single GDB executable that supports multiple remote
2193 target architectures.
2195 * GDB now supports debugging C and C++ programs which use the
2196 Decimal Floating Point extension. In addition, the PowerPC target
2197 now has a set of pseudo-registers to inspect decimal float values
2198 stored in two consecutive float registers.
2200 * The -break-insert MI command can optionally create pending
2203 * Improved support for debugging Ada
2204 Many improvements to the Ada language support have been made. These
2206 - Better support for Ada2005 interface types
2207 - Improved handling of arrays and slices in general
2208 - Better support for Taft-amendment types
2209 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2211 - Improved command completion in Ada
2214 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2219 set print frame-arguments (all|scalars|none)
2220 show print frame-arguments
2221 The value of this variable can be changed to control which argument
2222 values should be printed by the debugger when displaying a frame.
2227 Transfer files to and from a remote target, and delete remote files.
2234 Transfer files to and from a remote target, and delete remote files.
2236 * New remote packets
2243 Open, close, read, write, and delete files on the remote system.
2246 Attach to an existing process on the remote system, in extended-remote
2250 Run a new process on the remote system, in extended-remote mode.
2252 *** Changes in GDB 6.7
2254 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2255 bfd, libiberty and opcodes, as revealed by static analysis donated by
2256 Coverity, Inc. (http://scan.coverity.com).
2258 * When looking up multiply-defined global symbols, GDB will now prefer the
2259 symbol definition in the current shared library if it was built using the
2260 -Bsymbolic linker option.
2262 * When the Text User Interface (TUI) is not configured, GDB will now
2263 recognize the -tui command-line option and print a message that the TUI
2266 * The GDB remote stub, gdbserver, now has lower overhead for high
2267 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2269 * GDB for MIPS targets now autodetects whether a remote target provides
2270 32-bit or 64-bit register values.
2272 * Support for C++ member pointers has been improved.
2274 * GDB now understands XML target descriptions, which specify the
2275 target's overall architecture. GDB can read a description from
2276 a local file or over the remote serial protocol.
2278 * Vectors of single-byte data use a new integer type which is not
2279 automatically displayed as character or string data.
2281 * The /s format now works with the print command. It displays
2282 arrays of single-byte integers and pointers to single-byte integers
2285 * Target descriptions can now describe target-specific registers,
2286 for architectures which have implemented the support (currently
2287 only ARM, M68K, and MIPS).
2289 * GDB and the GDB remote stub, gdbserver, now support the XScale
2292 * The GDB remote stub, gdbserver, has been updated to support
2293 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2294 has been rewritten to use the standard GDB remote protocol.
2296 * GDB can now step into C++ functions which are called through thunks.
2298 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2300 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2301 layout. It also supports a TextSeg= and DataSeg= response when only
2302 segment base addresses (rather than offsets) are available.
2304 * The /i format now outputs any trailing branch delay slot instructions
2305 immediately following the last instruction within the count specified.
2307 * The GDB remote protocol "T" stop reply packet now supports a
2308 "library" response. Combined with the new "qXfer:libraries:read"
2309 packet, this response allows GDB to debug shared libraries on targets
2310 where the operating system manages the list of loaded libraries (e.g.
2311 Windows and SymbianOS).
2313 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2314 (DLLs) on Windows and Windows CE targets.
2316 * GDB now supports a faster verification that a .debug file matches its binary
2317 according to its build-id signature, if the signature is present.
2323 Enable or disable hardware flow control (RTS/CTS) on the serial port
2324 when debugging using remote targets.
2326 set mem inaccessible-by-default
2327 show mem inaccessible-by-default
2328 If the target supplies a memory map, for instance via the remote
2329 protocol's "qXfer:memory-map:read" packet, setting this variable
2330 prevents GDB from accessing memory outside the memory map. This
2331 is useful for targets with memory mapped registers or which react
2332 badly to accesses of unmapped address space.
2334 set breakpoint auto-hw
2335 show breakpoint auto-hw
2336 If the target supplies a memory map, for instance via the remote
2337 protocol's "qXfer:memory-map:read" packet, setting this variable
2338 lets GDB use hardware breakpoints automatically for memory regions
2339 where it can not use software breakpoints. This covers both the
2340 "break" command and internal breakpoints used for other commands
2341 including "next" and "finish".
2344 catch exception unhandled
2345 Stop the program execution when Ada exceptions are raised.
2348 Stop the program execution when an Ada assertion failed.
2352 Set an alternate system root for target files. This is a more
2353 general version of "set solib-absolute-prefix", which is now
2354 an alias to "set sysroot".
2357 Provide extended SPU facility status information. This set of
2358 commands is available only when debugging the Cell/B.E. SPU
2361 * New native configurations
2363 OpenBSD/sh sh*-*openbsd*
2366 unset tdesc filename
2368 Use the specified local file as an XML target description, and do
2369 not query the target for its built-in description.
2373 OpenBSD/sh sh*-*-openbsd*
2374 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2375 Toshiba Media Processor mep-elf
2377 * New remote packets
2380 Ignore the specified signals; pass them directly to the debugged program
2381 without stopping other threads or reporting them to GDB.
2383 qXfer:features:read:
2384 Read an XML target description from the target, which describes its
2389 Read or write contents of an spufs file on the target system. These
2390 packets are available only on the Cell/B.E. SPU architecture.
2392 qXfer:libraries:read:
2393 Report the loaded shared libraries. Combined with new "T" packet
2394 response, this packet allows GDB to debug shared libraries on
2395 targets where the operating system manages the list of loaded
2396 libraries (e.g. Windows and SymbianOS).
2400 Support for these obsolete configurations has been removed.
2408 i[34567]86-*-lynxos*
2409 i[34567]86-*-netware*
2410 i[34567]86-*-sco3.2v5*
2411 i[34567]86-*-sco3.2v4*
2413 i[34567]86-*-sysv4.2*
2416 i[34567]86-*-unixware2*
2417 i[34567]86-*-unixware*
2426 * Other removed features
2433 Various m68k-only ROM monitors.
2440 Various Renesas ROM monitors and debugging interfaces for SH and
2445 Support for a Macraigor serial interface to on-chip debugging.
2446 GDB does not directly support the newer parallel or USB
2451 A debug information format. The predecessor to DWARF 2 and
2452 DWARF 3, which are still supported.
2454 Support for the HP aCC compiler on HP-UX/PA-RISC
2456 SOM-encapsulated symbolic debugging information, automatic
2457 invocation of pxdb, and the aCC custom C++ ABI. This does not
2458 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2459 with aCC can still be debugged on an assembly level.
2461 MIPS ".pdr" sections
2463 A MIPS-specific format used to describe stack frame layout
2464 in debugging information.
2468 GDB could work with an older version of Guile to debug
2469 the interpreter and Scheme programs running in it.
2471 set mips stack-arg-size
2472 set mips saved-gpreg-size
2474 Use "set mips abi" to control parameter passing for MIPS.
2476 *** Changes in GDB 6.6
2481 Cell Broadband Engine SPU spu-elf
2483 * GDB can now be configured as a cross-debugger targeting native Windows
2484 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2485 running on a Windows system over TCP/IP to debug Windows programs.
2487 * The GDB remote stub, gdbserver, has been updated to support Windows and
2488 Cygwin debugging. Both single-threaded and multi-threaded programs are
2491 * The "set trust-readonly-sections" command works again. This command was
2492 broken in GDB 6.3, 6.4, and 6.5.
2494 * The "load" command now supports writing to flash memory, if the remote
2495 stub provides the required support.
2497 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2498 longer requires symbolic debug information (e.g. DWARF-2).
2503 unset substitute-path
2504 show substitute-path
2505 Manage a list of substitution rules that GDB uses to rewrite the name
2506 of the directories where the sources are located. This can be useful
2507 for instance when the sources were moved to a different location
2508 between compilation and debugging.
2512 Print each CLI command as it is executed. Each command is prefixed with
2513 a number of `+' symbols representing the nesting depth.
2514 The source command now has a `-v' option to enable the same feature.
2518 The ARM Demon monitor support (RDP protocol, "target rdp").
2520 Kernel Object Display, an embedded debugging feature which only worked with
2521 an obsolete version of Cisco IOS.
2523 The 'set download-write-size' and 'show download-write-size' commands.
2525 * New remote packets
2528 Tell a stub about GDB client features, and request remote target features.
2529 The first feature implemented is PacketSize, which allows the target to
2530 specify the size of packets it can handle - to minimize the number of
2531 packets required and improve performance when connected to a remote
2535 Fetch an OS auxilliary vector from the remote stub. This packet is a
2536 more efficient replacement for qPart:auxv:read.
2538 qXfer:memory-map:read:
2539 Fetch a memory map from the remote stub, including information about
2540 RAM, ROM, and flash memory devices.
2545 Erase and program a flash memory device.
2547 * Removed remote packets
2550 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2551 used it, and only gdbserver implemented it.
2553 *** Changes in GDB 6.5
2557 Renesas M32C/M16C m32c-elf
2559 Morpho Technologies ms1 ms1-elf
2563 init-if-undefined Initialize a convenience variable, but
2564 only if it doesn't already have a value.
2566 The following commands are presently only implemented for native GNU/Linux:
2568 checkpoint Save a snapshot of the program state.
2570 restart <n> Return the program state to a
2571 previously saved state.
2573 info checkpoints List currently saved checkpoints.
2575 delete-checkpoint <n> Delete a previously saved checkpoint.
2577 set|show detach-on-fork Tell gdb whether to detach from a newly
2578 forked process, or to keep debugging it.
2580 info forks List forks of the user program that
2581 are available to be debugged.
2583 fork <n> Switch to debugging one of several
2584 forks of the user program that are
2585 available to be debugged.
2587 delete-fork <n> Delete a fork from the list of forks
2588 that are available to be debugged (and
2589 kill the forked process).
2591 detach-fork <n> Delete a fork from the list of forks
2592 that are available to be debugged (and
2593 allow the process to continue).
2597 Morpho Technologies ms2 ms1-elf
2599 * Improved Windows host support
2601 GDB now builds as a cross debugger hosted on i686-mingw32, including
2602 native console support, and remote communications using either
2603 network sockets or serial ports.
2605 * Improved Modula-2 language support
2607 GDB can now print most types in the Modula-2 syntax. This includes:
2608 basic types, set types, record types, enumerated types, range types,
2609 pointer types and ARRAY types. Procedure var parameters are correctly
2610 printed and hexadecimal addresses and character constants are also
2611 written in the Modula-2 syntax. Best results can be obtained by using
2612 GNU Modula-2 together with the -gdwarf-2 command line option.
2616 The ARM rdi-share module.
2618 The Netware NLM debug server.
2620 *** Changes in GDB 6.4
2622 * New native configurations
2624 OpenBSD/arm arm*-*-openbsd*
2625 OpenBSD/mips64 mips64-*-openbsd*
2629 Morpho Technologies ms1 ms1-elf
2631 * New command line options
2633 --batch-silent As for --batch, but totally silent.
2634 --return-child-result The debugger will exist with the same value
2635 the child (debugged) program exited with.
2636 --eval-command COMMAND, -ex COMMAND
2637 Execute a single GDB CLI command. This may be
2638 specified multiple times and in conjunction
2639 with the --command (-x) option.
2641 * Deprecated commands removed
2643 The following commands, that were deprecated in 2000, have been
2647 set|show arm disassembly-flavor set|show arm disassembler
2648 othernames set arm disassembler
2649 set|show remotedebug set|show debug remote
2650 set|show archdebug set|show debug arch
2651 set|show eventdebug set|show debug event
2654 * New BSD user-level threads support
2656 It is now possible to debug programs using the user-level threads
2657 library on OpenBSD and FreeBSD. Currently supported (target)
2660 FreeBSD/amd64 x86_64-*-freebsd*
2661 FreeBSD/i386 i386-*-freebsd*
2662 OpenBSD/i386 i386-*-openbsd*
2664 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2665 are not yet supported.
2667 * New support for Matsushita MN10300 w/sim added
2668 (Work in progress). mn10300-elf.
2670 * REMOVED configurations and files
2672 VxWorks and the XDR protocol *-*-vxworks
2673 Motorola MCORE mcore-*-*
2674 National Semiconductor NS32000 ns32k-*-*
2676 * New "set print array-indexes" command
2678 After turning this setting "on", GDB prints the index of each element
2679 when displaying arrays. The default is "off" to preserve the previous
2682 * VAX floating point support
2684 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2686 * User-defined command support
2688 In addition to using $arg0..$arg9 for argument passing, it is now possible
2689 to use $argc to determine now many arguments have been passed. See the
2690 section on user-defined commands in the user manual for more information.
2692 *** Changes in GDB 6.3:
2694 * New command line option
2696 GDB now accepts -l followed by a number to set the timeout for remote
2699 * GDB works with GCC -feliminate-dwarf2-dups
2701 GDB now supports a more compact representation of DWARF-2 debug
2702 information using DW_FORM_ref_addr references. These are produced
2703 by GCC with the option -feliminate-dwarf2-dups and also by some
2704 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2705 to use -feliminate-dwarf2-dups.
2707 * Internationalization
2709 When supported by the host system, GDB will be built with
2710 internationalization (libintl). The task of marking up the sources is
2711 continued, we're looking forward to our first translation.
2715 Initial support for debugging programs compiled with the GNAT
2716 implementation of the Ada programming language has been integrated
2717 into GDB. In this release, support is limited to expression evaluation.
2719 * New native configurations
2721 GNU/Linux/m32r m32r-*-linux-gnu
2725 GDB's remote protocol now includes support for the 'p' packet. This
2726 packet is used to fetch individual registers from a remote inferior.
2728 * END-OF-LIFE registers[] compatibility module
2730 GDB's internal register infrastructure has been completely rewritten.
2731 The new infrastructure making possible the implementation of key new
2732 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2735 GDB 6.3 will be the last release to include the the registers[]
2736 compatibility module that allowed out-of-date configurations to
2737 continue to work. This change directly impacts the following
2747 powerpc bdm protocol
2749 Unless there is activity to revive these configurations, they will be
2750 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2752 * OBSOLETE configurations and files
2754 Configurations that have been declared obsolete in this release have
2755 been commented out. Unless there is activity to revive these
2756 configurations, the next release of GDB will have their sources
2757 permanently REMOVED.
2766 *** Changes in GDB 6.2.1:
2768 * MIPS `break main; run' gave an heuristic-fence-post warning
2770 When attempting to run even a simple program, a warning about
2771 heuristic-fence-post being hit would be reported. This problem has
2774 * MIPS IRIX 'long double' crashed GDB
2776 When examining a long double variable, GDB would get a segmentation
2777 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2778 IRIX long double values).
2782 A bug in the VAX stack code was causing problems with the "next"
2783 command. This problem has been fixed.
2785 *** Changes in GDB 6.2:
2787 * Fix for ``many threads''
2789 On GNU/Linux systems that use the NPTL threads library, a program
2790 rapidly creating and deleting threads would confuse GDB leading to the
2793 ptrace: No such process.
2794 thread_db_get_info: cannot get thread info: generic error
2796 This problem has been fixed.
2798 * "-async" and "-noasync" options removed.
2800 Support for the broken "-noasync" option has been removed (it caused
2803 * New ``start'' command.
2805 This command runs the program until the begining of the main procedure.
2807 * New BSD Kernel Data Access Library (libkvm) interface
2809 Using ``target kvm'' it is now possible to debug kernel core dumps and
2810 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2811 platforms. Currently supported (native-only) configurations are:
2813 FreeBSD/amd64 x86_64-*-freebsd*
2814 FreeBSD/i386 i?86-*-freebsd*
2815 NetBSD/i386 i?86-*-netbsd*
2816 NetBSD/m68k m68*-*-netbsd*
2817 NetBSD/sparc sparc-*-netbsd*
2818 OpenBSD/amd64 x86_64-*-openbsd*
2819 OpenBSD/i386 i?86-*-openbsd*
2820 OpenBSD/m68k m68*-openbsd*
2821 OpenBSD/sparc sparc-*-openbsd*
2823 * Signal trampoline code overhauled
2825 Many generic problems with GDB's signal handling code have been fixed.
2826 These include: backtraces through non-contiguous stacks; recognition
2827 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2828 call; backtrace through a signal trampoline; step into and out of
2829 signal handlers; and single-stepping in the signal trampoline.
2831 Please note that kernel bugs are a limiting factor here. These
2832 features have been shown to work on an s390 GNU/Linux system that
2833 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2835 * Cygwin support for DWARF 2 added.
2837 * New native configurations
2839 GNU/Linux/hppa hppa*-*-linux*
2840 OpenBSD/hppa hppa*-*-openbsd*
2841 OpenBSD/m68k m68*-*-openbsd*
2842 OpenBSD/m88k m88*-*-openbsd*
2843 OpenBSD/powerpc powerpc-*-openbsd*
2844 NetBSD/vax vax-*-netbsd*
2845 OpenBSD/vax vax-*-openbsd*
2847 * END-OF-LIFE frame compatibility module
2849 GDB's internal frame infrastructure has been completely rewritten.
2850 The new infrastructure making it possible to support key new features
2851 including DWARF 2 Call Frame Information. To aid in the task of
2852 migrating old configurations to this new infrastructure, a
2853 compatibility module, that allowed old configurations to continue to
2854 work, was also included.
2856 GDB 6.2 will be the last release to include this frame compatibility
2857 module. This change directly impacts the following configurations:
2867 Unless there is activity to revive these configurations, they will be
2868 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2870 * REMOVED configurations and files
2872 Sun 3, running SunOS 3 m68*-*-sunos3*
2873 Sun 3, running SunOS 4 m68*-*-sunos4*
2874 Sun 2, running SunOS 3 m68000-*-sunos3*
2875 Sun 2, running SunOS 4 m68000-*-sunos4*
2876 Motorola 680x0 running LynxOS m68*-*-lynxos*
2877 AT&T 3b1/Unix pc m68*-att-*
2878 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2879 decstation mips-dec-* mips-little-*
2880 riscos mips-*-riscos* mips-*-sysv*
2881 sonymips mips-sony-*
2882 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2884 *** Changes in GDB 6.1.1:
2886 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2888 The TUI (Text-mode User Interface) is now built as part of a default
2889 GDB configuration. It is enabled by either selecting the TUI with the
2890 command line option "-i=tui" or by running the separate "gdbtui"
2891 program. For more information on the TUI, see the manual "Debugging
2894 * Pending breakpoint support (also included in GDB 6.1)
2896 Support has been added to allow you to specify breakpoints in shared
2897 libraries that have not yet been loaded. If a breakpoint location
2898 cannot be found, and the "breakpoint pending" option is set to auto,
2899 GDB queries you if you wish to make the breakpoint pending on a future
2900 shared-library load. If and when GDB resolves the breakpoint symbol,
2901 the pending breakpoint is removed as one or more regular breakpoints
2904 Pending breakpoints are very useful for GCJ Java debugging.
2906 * Fixed ISO-C build problems
2908 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2909 non ISO-C code that stopped them being built using a more strict ISO-C
2910 compiler (e.g., IBM's C compiler).
2912 * Fixed build problem on IRIX 5
2914 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2915 wasn't able to compile compile on an IRIX 5 system.
2917 * Added execute permission to gdb/gdbserver/configure
2919 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2920 permission. This bug would cause configure to fail on a number of
2921 systems (Solaris, IRIX). Ref: server/519.
2923 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2925 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2926 has been updated to use constant array sizes.
2928 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2930 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2931 its generated DWARF Call Frame Info. This encoding was causing GDB to
2932 panic, that panic has been fixed. Ref: gdb/1628.
2934 * Fixed a problem when examining parameters in shared library code.
2936 When examining parameters in optimized shared library code generated
2937 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2938 not available''. GDB now correctly displays the variable's value.
2940 *** Changes in GDB 6.1:
2942 * Removed --with-mmalloc
2944 Support for the mmalloc memory manager has been removed, as it
2945 conflicted with the internal gdb byte cache.
2947 * Changes in AMD64 configurations
2949 The AMD64 target now includes the %cs and %ss registers. As a result
2950 the AMD64 remote protocol has changed; this affects the floating-point
2951 and SSE registers. If you rely on those registers for your debugging,
2952 you should upgrade gdbserver on the remote side.
2954 * Revised SPARC target
2956 The SPARC target has been completely revised, incorporating the
2957 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2958 support for LynxOS and SunOS 4 has been dropped. Calling functions
2959 from within GDB on operating systems with a non-executable stack
2960 (Solaris, OpenBSD) now works.
2964 GDB has a new C++ demangler which does a better job on the mangled
2965 names generated by current versions of g++. It also runs faster, so
2966 with this and other changes gdb should now start faster on large C++
2969 * DWARF 2 Location Expressions
2971 GDB support for location expressions has been extended to support function
2972 arguments and frame bases. Older versions of GDB could crash when they
2975 * C++ nested types and namespaces
2977 GDB's support for nested types and namespaces in C++ has been
2978 improved, especially if you use the DWARF 2 debugging format. (This
2979 is the default for recent versions of GCC on most platforms.)
2980 Specifically, if you have a class "Inner" defined within a class or
2981 namespace "Outer", then GDB realizes that the class's name is
2982 "Outer::Inner", not simply "Inner". This should greatly reduce the
2983 frequency of complaints about not finding RTTI symbols. In addition,
2984 if you are stopped at inside of a function defined within a namespace,
2985 GDB modifies its name lookup accordingly.
2987 * New native configurations
2989 NetBSD/amd64 x86_64-*-netbsd*
2990 OpenBSD/amd64 x86_64-*-openbsd*
2991 OpenBSD/alpha alpha*-*-openbsd*
2992 OpenBSD/sparc sparc-*-openbsd*
2993 OpenBSD/sparc64 sparc64-*-openbsd*
2995 * New debugging protocols
2997 M32R with SDI protocol m32r-*-elf*
2999 * "set prompt-escape-char" command deleted.
3001 The command "set prompt-escape-char" has been deleted. This command,
3002 and its very obscure effet on GDB's prompt, was never documented,
3003 tested, nor mentioned in the NEWS file.
3005 * OBSOLETE configurations and files
3007 Configurations that have been declared obsolete in this release have
3008 been commented out. Unless there is activity to revive these
3009 configurations, the next release of GDB will have their sources
3010 permanently REMOVED.
3012 Sun 3, running SunOS 3 m68*-*-sunos3*
3013 Sun 3, running SunOS 4 m68*-*-sunos4*
3014 Sun 2, running SunOS 3 m68000-*-sunos3*
3015 Sun 2, running SunOS 4 m68000-*-sunos4*
3016 Motorola 680x0 running LynxOS m68*-*-lynxos*
3017 AT&T 3b1/Unix pc m68*-att-*
3018 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3019 decstation mips-dec-* mips-little-*
3020 riscos mips-*-riscos* mips-*-sysv*
3021 sonymips mips-sony-*
3022 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3024 * REMOVED configurations and files
3026 SGI Irix-4.x mips-sgi-irix4 or iris4
3027 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3028 Z8000 simulator z8k-zilog-none or z8ksim
3029 Matsushita MN10200 w/simulator mn10200-*-*
3030 H8/500 simulator h8500-hitachi-hms or h8500hms
3031 HP/PA running BSD hppa*-*-bsd*
3032 HP/PA running OSF/1 hppa*-*-osf*
3033 HP/PA Pro target hppa*-*-pro*
3034 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3035 386BSD i[3456]86-*-bsd*
3036 Sequent family i[3456]86-sequent-sysv4*
3037 i[3456]86-sequent-sysv*
3038 i[3456]86-sequent-bsd*
3039 SPARC running LynxOS sparc-*-lynxos*
3040 SPARC running SunOS 4 sparc-*-sunos4*
3041 Tsqware Sparclet sparclet-*-*
3042 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3044 *** Changes in GDB 6.0:
3048 Support for debugging the Objective-C programming language has been
3049 integrated into GDB.
3051 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3053 DWARF 2's Call Frame Information makes available compiler generated
3054 information that more exactly describes the program's run-time stack.
3055 By using this information, GDB is able to provide more robust stack
3058 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3059 have been updated to use a new backtrace mechanism which includes
3060 DWARF 2 CFI support.
3064 GDB's remote protocol has been extended to include support for hosted
3065 file I/O (where the remote target uses GDB's file system). See GDB's
3066 remote protocol documentation for details.
3068 * All targets using the new architecture framework.
3070 All of GDB's targets have been updated to use the new internal
3071 architecture framework. The way is now open for future GDB releases
3072 to include cross-architecture native debugging support (i386 on amd64,
3075 * GNU/Linux's Thread Local Storage (TLS)
3077 GDB now includes support for for the GNU/Linux implementation of
3078 per-thread variables.
3080 * GNU/Linux's Native POSIX Thread Library (NPTL)
3082 GDB's thread code has been updated to work with either the new
3083 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3085 * Separate debug info.
3087 GDB, in conjunction with BINUTILS, now supports a mechanism for
3088 automatically loading debug information from a separate file. Instead
3089 of shipping full debug and non-debug versions of system libraries,
3090 system integrators can now instead ship just the stripped libraries
3091 and optional debug files.
3093 * DWARF 2 Location Expressions
3095 DWARF 2 Location Expressions allow the compiler to more completely
3096 describe the location of variables (even in optimized code) to the
3099 GDB now includes preliminary support for location expressions (support
3100 for DW_OP_piece is still missing).
3104 A number of long standing bugs that caused GDB to die while starting a
3105 Java application have been fixed. GDB's Java support is now
3106 considered "useable".
3108 * GNU/Linux support for fork, vfork, and exec.
3110 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3111 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3114 * GDB supports logging output to a file
3116 There are two new commands, "set logging" and "show logging", which can be
3117 used to capture GDB's output to a file.
3119 * The meaning of "detach" has changed for gdbserver
3121 The "detach" command will now resume the application, as documented. To
3122 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3125 * d10v, m68hc11 `regs' command deprecated
3127 The `info registers' command has been updated so that it displays the
3128 registers using a format identical to the old `regs' command.
3132 A new command, "maint set profile on/off", has been added. This command can
3133 be used to enable or disable profiling while running GDB, to profile a
3134 session or a set of commands. In addition there is a new configure switch,
3135 "--enable-profiling", which will cause GDB to be compiled with profiling
3136 data, for more informative profiling results.
3138 * Default MI syntax changed to "mi2".
3140 The default MI (machine interface) syntax, enabled by the command line
3141 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3142 "mi1", can be enabled by specifying the option "-i=mi1".
3144 Support for the original "mi0" syntax (included in GDB 5.0) has been
3147 Fix for gdb/192: removed extraneous space when displaying frame level.
3148 Fix for gdb/672: update changelist is now output in mi list format.
3149 Fix for gdb/702: a -var-assign that updates the value now shows up
3150 in a subsequent -var-update.
3152 * New native configurations.
3154 FreeBSD/amd64 x86_64-*-freebsd*
3156 * Multi-arched targets.
3158 HP/PA HPUX11 hppa*-*-hpux*
3159 Renesas M32R/D w/simulator m32r-*-elf*
3161 * OBSOLETE configurations and files
3163 Configurations that have been declared obsolete in this release have
3164 been commented out. Unless there is activity to revive these
3165 configurations, the next release of GDB will have their sources
3166 permanently REMOVED.
3168 Z8000 simulator z8k-zilog-none or z8ksim
3169 Matsushita MN10200 w/simulator mn10200-*-*
3170 H8/500 simulator h8500-hitachi-hms or h8500hms
3171 HP/PA running BSD hppa*-*-bsd*
3172 HP/PA running OSF/1 hppa*-*-osf*
3173 HP/PA Pro target hppa*-*-pro*
3174 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3175 Sequent family i[3456]86-sequent-sysv4*
3176 i[3456]86-sequent-sysv*
3177 i[3456]86-sequent-bsd*
3178 Tsqware Sparclet sparclet-*-*
3179 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3181 * REMOVED configurations and files
3184 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3185 IBM AIX PS/2 i[3456]86-*-aix
3186 i386 running Mach 3.0 i[3456]86-*-mach3*
3187 i386 running Mach i[3456]86-*-mach*
3188 i386 running OSF/1 i[3456]86-*osf1mk*
3189 HP/Apollo 68k Family m68*-apollo*-sysv*,
3191 m68*-hp-bsd*, m68*-hp-hpux*
3192 Argonaut Risc Chip (ARC) arc-*-*
3193 Mitsubishi D30V d30v-*-*
3194 Fujitsu FR30 fr30-*-elf*
3195 OS/9000 i[34]86-*-os9k
3196 I960 with MON960 i960-*-coff
3198 * MIPS $fp behavior changed
3200 The convenience variable $fp, for the MIPS, now consistently returns
3201 the address of the current frame's base. Previously, depending on the
3202 context, $fp could refer to either $sp or the current frame's base
3203 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3204 The GNU Source-Level Debugger''.
3206 *** Changes in GDB 5.3:
3208 * GNU/Linux shared library multi-threaded performance improved.
3210 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3211 `/proc', in preference to `ptrace' for memory reads. This may result
3212 in an improvement in the start-up time of multi-threaded, shared
3213 library applications when run under GDB. One GDB user writes: ``loads
3214 shared libs like mad''.
3216 * ``gdbserver'' now supports multi-threaded applications on some targets
3218 Support for debugging multi-threaded applications which use
3219 the GNU/Linux LinuxThreads package has been added for
3220 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3221 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3223 * GDB now supports C/C++ preprocessor macros.
3225 GDB now expands preprocessor macro invocations in C/C++ expressions,
3226 and provides various commands for showing macro definitions and how
3229 The new command `macro expand EXPRESSION' expands any macro
3230 invocations in expression, and shows the result.
3232 The new command `show macro MACRO-NAME' shows the definition of the
3233 macro named MACRO-NAME, and where it was defined.
3235 Most compilers don't include information about macros in the debugging
3236 information by default. In GCC 3.1, for example, you need to compile
3237 your program with the options `-gdwarf-2 -g3'. If the macro
3238 information is present in the executable, GDB will read it.
3240 * Multi-arched targets.
3242 DEC Alpha (partial) alpha*-*-*
3243 DEC VAX (partial) vax-*-*
3245 National Semiconductor NS32000 (partial) ns32k-*-*
3246 Motorola 68000 (partial) m68k-*-*
3247 Motorola MCORE mcore-*-*
3251 Fujitsu FRV architecture added by Red Hat frv*-*-*
3254 * New native configurations
3256 Alpha NetBSD alpha*-*-netbsd*
3257 SH NetBSD sh*-*-netbsdelf*
3258 MIPS NetBSD mips*-*-netbsd*
3259 UltraSPARC NetBSD sparc64-*-netbsd*
3261 * OBSOLETE configurations and files
3263 Configurations that have been declared obsolete in this release have
3264 been commented out. Unless there is activity to revive these
3265 configurations, the next release of GDB will have their sources
3266 permanently REMOVED.
3268 Mitsubishi D30V d30v-*-*
3269 OS/9000 i[34]86-*-os9k
3270 IBM AIX PS/2 i[3456]86-*-aix
3271 Fujitsu FR30 fr30-*-elf*
3272 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3273 Argonaut Risc Chip (ARC) arc-*-*
3274 i386 running Mach 3.0 i[3456]86-*-mach3*
3275 i386 running Mach i[3456]86-*-mach*
3276 i386 running OSF/1 i[3456]86-*osf1mk*
3277 HP/Apollo 68k Family m68*-apollo*-sysv*,
3279 m68*-hp-bsd*, m68*-hp-hpux*
3280 I960 with MON960 i960-*-coff
3282 * OBSOLETE languages
3284 CHILL, a Pascal like language used by telecommunications companies.
3286 * REMOVED configurations and files
3288 AMD 29k family via UDI a29k-amd-udi, udi29k
3289 A29K VxWorks a29k-*-vxworks
3290 AMD 29000 embedded, using EBMON a29k-none-none
3291 AMD 29000 embedded with COFF a29k-none-coff
3292 AMD 29000 embedded with a.out a29k-none-aout
3294 testsuite/gdb.hp/gdb.threads-hp/ directory
3296 * New command "set max-user-call-depth <nnn>"
3298 This command allows the user to limit the call depth of user-defined
3299 commands. The default is 1024.
3301 * Changes in FreeBSD/i386 native debugging.
3303 Support for the "generate-core-file" has been added.
3305 * New commands "dump", "append", and "restore".
3307 These commands allow data to be copied from target memory
3308 to a bfd-format or binary file (dump and append), and back
3309 from a file into memory (restore).
3311 * Improved "next/step" support on multi-processor Alpha Tru64.
3313 The previous single-step mechanism could cause unpredictable problems,
3314 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3315 of a software single-step mechanism prevents this.
3317 *** Changes in GDB 5.2.1:
3325 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3326 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3327 Fix, by Joel Brobecker imported from mainline.
3329 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3330 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3331 Fix, by Fred Fish, imported from mainline.
3333 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3334 Surprisingly enough, it works now.
3335 By Michal Ludvig, imported from mainline.
3337 i386 hardware watchpoint support:
3338 avoid misses on second run for some targets.
3339 By Pierre Muller, imported from mainline.
3341 *** Changes in GDB 5.2:
3343 * New command "set trust-readonly-sections on[off]".
3345 This command is a hint that tells gdb that read-only sections
3346 really are read-only (ie. that their contents will not change).
3347 In this mode, gdb will go to the object file rather than the
3348 target to read memory from read-only sections (such as ".text").
3349 This can be a significant performance improvement on some
3350 (notably embedded) targets.
3352 * New command "generate-core-file" (or "gcore").
3354 This new gdb command allows the user to drop a core file of the child
3355 process state at any time. So far it's been implemented only for
3356 GNU/Linux and Solaris, but should be relatively easily ported to other
3357 hosts. Argument is core file name (defaults to core.<pid>).
3359 * New command line option
3361 GDB now accepts --pid or -p followed by a process id.
3363 * Change in command line behavior -- corefiles vs. process ids.
3365 There is a subtle behavior in the way in which GDB handles
3366 command line arguments. The first non-flag argument is always
3367 a program to debug, but the second non-flag argument may either
3368 be a corefile or a process id. Previously, GDB would attempt to
3369 open the second argument as a corefile, and if that failed, would
3370 issue a superfluous error message and then attempt to attach it as
3371 a process. Now, if the second argument begins with a non-digit,
3372 it will be treated as a corefile. If it begins with a digit,
3373 GDB will attempt to attach it as a process, and if no such process
3374 is found, will then attempt to open it as a corefile.
3376 * Changes in ARM configurations.
3378 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3379 configuration is fully multi-arch.
3381 * New native configurations
3383 ARM NetBSD arm*-*-netbsd*
3384 x86 OpenBSD i[3456]86-*-openbsd*
3385 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3386 Sparc64 running FreeBSD sparc64-*-freebsd*
3390 Sanyo XStormy16 xstormy16-elf
3392 * OBSOLETE configurations and files
3394 Configurations that have been declared obsolete in this release have
3395 been commented out. Unless there is activity to revive these
3396 configurations, the next release of GDB will have their sources
3397 permanently REMOVED.
3399 AMD 29k family via UDI a29k-amd-udi, udi29k
3400 A29K VxWorks a29k-*-vxworks
3401 AMD 29000 embedded, using EBMON a29k-none-none
3402 AMD 29000 embedded with COFF a29k-none-coff
3403 AMD 29000 embedded with a.out a29k-none-aout
3405 testsuite/gdb.hp/gdb.threads-hp/ directory
3407 * REMOVED configurations and files
3409 TI TMS320C80 tic80-*-*
3411 PowerPC Solaris powerpcle-*-solaris*
3412 PowerPC Windows NT powerpcle-*-cygwin32
3413 PowerPC Netware powerpc-*-netware*
3414 Harris/CXUX m88k m88*-harris-cxux*
3415 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3416 ns32k-utek-sysv* ns32k-utek-*
3417 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3418 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3419 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3420 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3421 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3423 * Changes to command line processing
3425 The new `--args' feature can be used to specify command-line arguments
3426 for the inferior from gdb's command line.
3428 * Changes to key bindings
3430 There is a new `operate-and-get-next' function bound to `C-o'.
3432 *** Changes in GDB 5.1.1
3434 Fix compile problem on DJGPP.
3436 Fix a problem with floating-point registers on the i386 being
3439 Fix to stop GDB crashing on .debug_str debug info.
3441 Numerous documentation fixes.
3443 Numerous testsuite fixes.
3445 *** Changes in GDB 5.1:
3447 * New native configurations
3449 Alpha FreeBSD alpha*-*-freebsd*
3450 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3451 MIPS GNU/Linux mips*-*-linux*
3452 MIPS SGI Irix 6.x mips*-sgi-irix6*
3453 ia64 AIX ia64-*-aix*
3454 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3458 Motorola 68HC11 and 68HC12 m68hc11-elf
3460 UltraSparc running GNU/Linux sparc64-*-linux*
3462 * OBSOLETE configurations and files
3464 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3465 Harris/CXUX m88k m88*-harris-cxux*
3466 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3467 ns32k-utek-sysv* ns32k-utek-*
3468 TI TMS320C80 tic80-*-*
3470 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3471 PowerPC Solaris powerpcle-*-solaris*
3472 PowerPC Windows NT powerpcle-*-cygwin32
3473 PowerPC Netware powerpc-*-netware*
3474 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3475 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3476 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3477 Apple Macintosh (MPW) host N/A
3479 stuff.c (Program to stuff files into a specially prepared space in kdb)
3480 kdb-start.c (Main loop for the standalone kernel debugger)
3482 Configurations that have been declared obsolete in this release have
3483 been commented out. Unless there is activity to revive these
3484 configurations, the next release of GDB will have their sources
3485 permanently REMOVED.
3487 * REMOVED configurations and files
3489 Altos 3068 m68*-altos-*
3490 Convex c1-*-*, c2-*-*
3492 ARM RISCix arm-*-* (as host)
3496 * GDB has been converted to ISO C.
3498 GDB's source code has been converted to ISO C. In particular, the
3499 sources are fully protoized, and rely on standard headers being
3504 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3506 * The MI enabled by default.
3508 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3509 revised and enabled by default. Packages which use GDB as a debugging
3510 engine behind a UI or another front end are encouraged to switch to
3511 using the GDB/MI interface, instead of the old annotations interface
3512 which is now deprecated.
3514 * Support for debugging Pascal programs.
3516 GDB now includes support for debugging Pascal programs. The following
3517 main features are supported:
3519 - Pascal-specific data types such as sets;
3521 - automatic recognition of Pascal sources based on file-name
3524 - Pascal-style display of data types, variables, and functions;
3526 - a Pascal expression parser.
3528 However, some important features are not yet supported.
3530 - Pascal string operations are not supported at all;
3532 - there are some problems with boolean types;
3534 - Pascal type hexadecimal constants are not supported
3535 because they conflict with the internal variables format;
3537 - support for Pascal objects and classes is not full yet;
3539 - unlike Pascal, GDB is case-sensitive for symbol names.
3541 * Changes in completion.
3543 Commands such as `shell', `run' and `set args', which pass arguments
3544 to inferior programs, now complete on file names, similar to what
3545 users expect at the shell prompt.
3547 Commands which accept locations, such as `disassemble', `print',
3548 `breakpoint', `until', etc. now complete on filenames as well as
3549 program symbols. Thus, if you type "break foob TAB", and the source
3550 files linked into the programs include `foobar.c', that file name will
3551 be one of the candidates for completion. However, file names are not
3552 considered for completion after you typed a colon that delimits a file
3553 name from a name of a function in that file, as in "break foo.c:bar".
3555 `set demangle-style' completes on available demangling styles.
3557 * New platform-independent commands:
3559 It is now possible to define a post-hook for a command as well as a
3560 hook that runs before the command. For more details, see the
3561 documentation of `hookpost' in the GDB manual.
3563 * Changes in GNU/Linux native debugging.
3565 Support for debugging multi-threaded programs has been completely
3566 revised for all platforms except m68k and sparc. You can now debug as
3567 many threads as your system allows you to have.
3569 Attach/detach is supported for multi-threaded programs.
3571 Support for SSE registers was added for x86. This doesn't work for
3572 multi-threaded programs though.
3574 * Changes in MIPS configurations.
3576 Multi-arch support is enabled for all MIPS configurations.
3578 GDB can now be built as native debugger on SGI Irix 6.x systems for
3579 debugging n32 executables. (Debugging 64-bit executables is not yet
3582 * Unified support for hardware watchpoints in all x86 configurations.
3584 Most (if not all) native x86 configurations support hardware-assisted
3585 breakpoints and watchpoints in a unified manner. This support
3586 implements debug register sharing between watchpoints, which allows to
3587 put a virtually infinite number of watchpoints on the same address,
3588 and also supports watching regions up to 16 bytes with several debug
3591 The new maintenance command `maintenance show-debug-regs' toggles
3592 debugging print-outs in functions that insert, remove, and test
3593 watchpoints and hardware breakpoints.
3595 * Changes in the DJGPP native configuration.
3597 New command ``info dos sysinfo'' displays assorted information about
3598 the CPU, OS, memory, and DPMI server.
3600 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3601 display information about segment descriptors stored in GDT, LDT, and
3604 New commands ``info dos pde'' and ``info dos pte'' display entries
3605 from Page Directory and Page Tables (for now works with CWSDPMI only).
3606 New command ``info dos address-pte'' displays the Page Table entry for
3607 a given linear address.
3609 GDB can now pass command lines longer than 126 characters to the
3610 program being debugged (requires an update to the libdbg.a library
3611 which is part of the DJGPP development kit).
3613 DWARF2 debug info is now supported.
3615 It is now possible to `step' and `next' through calls to `longjmp'.
3617 * Changes in documentation.
3619 All GDB documentation was converted to GFDL, the GNU Free
3620 Documentation License.
3622 Tracepoints-related commands are now fully documented in the GDB
3625 TUI, the Text-mode User Interface, is now documented in the manual.
3627 Tracepoints-related commands are now fully documented in the GDB
3630 The "GDB Internals" manual now has an index. It also includes
3631 documentation of `ui_out' functions, GDB coding standards, x86
3632 hardware watchpoints, and memory region attributes.
3634 * GDB's version number moved to ``version.in''
3636 The Makefile variable VERSION has been replaced by the file
3637 ``version.in''. People creating GDB distributions should update the
3638 contents of this file.
3642 GUD support is now a standard part of the EMACS distribution.
3644 *** Changes in GDB 5.0:
3646 * Improved support for debugging FP programs on x86 targets
3648 Unified and much-improved support for debugging floating-point
3649 programs on all x86 targets. In particular, ``info float'' now
3650 displays the FP registers in the same format on all x86 targets, with
3651 greater level of detail.
3653 * Improvements and bugfixes in hardware-assisted watchpoints
3655 It is now possible to watch array elements, struct members, and
3656 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3657 on x86 targets no longer erroneously trigger when the address is
3660 * Improvements in the native DJGPP version of GDB
3662 The distribution now includes all the scripts and auxiliary files
3663 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3664 machines ``out of the box''.
3666 The DJGPP version can now debug programs that use signals. It is
3667 possible to catch signals that happened in the debuggee, deliver
3668 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3669 would kill the program being debugged.) Programs that hook hardware
3670 interrupts (keyboard, timer, etc.) can also be debugged.
3672 It is now possible to debug DJGPP programs that redirect their
3673 standard handles or switch them to raw (as opposed to cooked) mode, or
3674 even close them. The command ``run < foo > bar'' works as expected,
3675 and ``info terminal'' reports useful information about the debuggee's
3676 terminal, including raw/cooked mode, redirection, etc.
3678 The DJGPP version now uses termios functions for console I/O, which
3679 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3682 DOS-style file names with drive letters are now fully supported by
3685 It is now possible to debug DJGPP programs that switch their working
3686 directory. It is also possible to rerun the debuggee any number of
3687 times without restarting GDB; thus, you can use the same setup,
3688 breakpoints, etc. for many debugging sessions.
3690 * New native configurations
3692 ARM GNU/Linux arm*-*-linux*
3693 PowerPC GNU/Linux powerpc-*-linux*
3697 Motorola MCore mcore-*-*
3698 x86 VxWorks i[3456]86-*-vxworks*
3699 PowerPC VxWorks powerpc-*-vxworks*
3700 TI TMS320C80 tic80-*-*
3702 * OBSOLETE configurations
3704 Altos 3068 m68*-altos-*
3705 Convex c1-*-*, c2-*-*
3707 ARM RISCix arm-*-* (as host)
3710 Configurations that have been declared obsolete will be commented out,
3711 but the code will be left in place. If there is no activity to revive
3712 these configurations before the next release of GDB, the sources will
3713 be permanently REMOVED.
3715 * Gould support removed
3717 Support for the Gould PowerNode and NP1 has been removed.
3719 * New features for SVR4
3721 On SVR4 native platforms (such as Solaris), if you attach to a process
3722 without first loading a symbol file, GDB will now attempt to locate and
3723 load symbols from the running process's executable file.
3725 * Many C++ enhancements
3727 C++ support has been greatly improved. Overload resolution now works properly
3728 in almost all cases. RTTI support is on the way.
3730 * Remote targets can connect to a sub-program
3732 A popen(3) style serial-device has been added. This device starts a
3733 sub-process (such as a stand-alone simulator) and then communicates
3734 with that. The sub-program to run is specified using the syntax
3735 ``|<program> <args>'' vis:
3737 (gdb) set remotedebug 1
3738 (gdb) target extended-remote |mn10300-elf-sim program-args
3740 * MIPS 64 remote protocol
3742 A long standing bug in the mips64 remote protocol where by GDB
3743 expected certain 32 bit registers (ex SR) to be transfered as 32
3744 instead of 64 bits has been fixed.
3746 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3747 added to provide backward compatibility with older versions of GDB.
3749 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3751 The command ``set remotebinarydownload'' command has been replaced by
3752 ``set remote X-packet''. Other commands in ``set remote'' family
3753 include ``set remote P-packet''.
3755 * Breakpoint commands accept ranges.
3757 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3758 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3759 ``tracepoint passcount'' also accepts a range of tracepoints.
3761 * ``apropos'' command added.
3763 The ``apropos'' command searches through command names and
3764 documentation strings, printing out matches, making it much easier to
3765 try to find a command that does what you are looking for.
3769 A new machine oriented interface (MI) has been added to GDB. This
3770 interface is designed for debug environments running GDB as a separate
3771 process. This is part of the long term libGDB project. See the
3772 "GDB/MI" chapter of the GDB manual for further information. It can be
3773 enabled by configuring with:
3775 .../configure --enable-gdbmi
3777 *** Changes in GDB-4.18:
3779 * New native configurations
3781 HP-UX 10.20 hppa*-*-hpux10.20
3782 HP-UX 11.x hppa*-*-hpux11.0*
3783 M68K GNU/Linux m68*-*-linux*
3787 Fujitsu FR30 fr30-*-elf*
3788 Intel StrongARM strongarm-*-*
3789 Mitsubishi D30V d30v-*-*
3791 * OBSOLETE configurations
3793 Gould PowerNode, NP1 np1-*-*, pn-*-*
3795 Configurations that have been declared obsolete will be commented out,
3796 but the code will be left in place. If there is no activity to revive
3797 these configurations before the next release of GDB, the sources will
3798 be permanently REMOVED.
3802 As a compatibility experiment, GDB's source files buildsym.h and
3803 buildsym.c have been converted to pure standard C, no longer
3804 containing any K&R compatibility code. We believe that all systems in
3805 use today either come with a standard C compiler, or have a GCC port
3806 available. If this is not true, please report the affected
3807 configuration to bug-gdb@gnu.org immediately. See the README file for
3808 information about getting a standard C compiler if you don't have one
3813 GDB now uses readline 2.2.
3815 * set extension-language
3817 You can now control the mapping between filename extensions and source
3818 languages by using the `set extension-language' command. For instance,
3819 you can ask GDB to treat .c files as C++ by saying
3820 set extension-language .c c++
3821 The command `info extensions' lists all of the recognized extensions
3822 and their associated languages.
3824 * Setting processor type for PowerPC and RS/6000
3826 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3827 you can use the `set processor' command to specify what variant of the
3828 PowerPC family you are debugging. The command
3832 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3833 following PowerPC and RS6000 variants:
3835 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3836 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3838 403GC IBM PowerPC 403GC
3839 505 Motorola PowerPC 505
3840 860 Motorola PowerPC 860 or 850
3841 601 Motorola PowerPC 601
3842 602 Motorola PowerPC 602
3843 603 Motorola/IBM PowerPC 603 or 603e
3844 604 Motorola PowerPC 604 or 604e
3845 750 Motorola/IBM PowerPC 750 or 750
3847 At the moment, this command just tells GDB what to name the
3848 special-purpose processor registers. Since almost all the affected
3849 registers are inaccessible to user-level programs, this command is
3850 only useful for remote debugging in its present form.
3854 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3855 more extensive support for HP-UX. Added features include shared
3856 library support, kernel threads and hardware watchpoints for 11.00,
3857 support for HP's ANSI C and C++ compilers, and a compatibility mode
3858 for xdb and dbx commands.
3862 HP's donation includes the new concept of catchpoints, which is a
3863 generalization of the old catch command. On HP-UX, it is now possible
3864 to catch exec, fork, and vfork, as well as library loading.
3866 This means that the existing catch command has changed; its first
3867 argument now specifies the type of catch to be set up. See the
3868 output of "help catch" for a list of catchpoint types.
3870 * Debugging across forks
3872 On HP-UX, you can choose which process to debug when a fork() happens
3877 HP has donated a curses-based terminal user interface (TUI). To get
3878 it, build with --enable-tui. Although this can be enabled for any
3879 configuration, at present it only works for native HP debugging.
3881 * GDB remote protocol additions
3883 A new protocol packet 'X' that writes binary data is now available.
3884 Default behavior is to try 'X', then drop back to 'M' if the stub
3885 fails to respond. The settable variable `remotebinarydownload'
3886 allows explicit control over the use of 'X'.
3888 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3889 full 64-bit address. The command
3891 set remoteaddresssize 32
3893 can be used to revert to the old behaviour. For existing remote stubs
3894 the change should not be noticed, as the additional address information
3897 In order to assist in debugging stubs, you may use the maintenance
3898 command `packet' to send any text string to the stub. For instance,
3900 maint packet heythere
3902 sends the packet "$heythere#<checksum>". Note that it is very easy to
3903 disrupt a debugging session by sending the wrong packet at the wrong
3906 The compare-sections command allows you to compare section data on the
3907 target to what is in the executable file without uploading or
3908 downloading, by comparing CRC checksums.
3910 * Tracing can collect general expressions
3912 You may now collect general expressions at tracepoints. This requires
3913 further additions to the target-side stub; see tracepoint.c and
3914 doc/agentexpr.texi for further details.
3916 * mask-address variable for Mips
3918 For Mips targets, you may control the zeroing of the upper 32 bits of
3919 a 64-bit address by entering `set mask-address on'. This is mainly
3920 of interest to users of embedded R4xxx and R5xxx processors.
3922 * Higher serial baud rates
3924 GDB's serial code now allows you to specify baud rates 57600, 115200,
3925 230400, and 460800 baud. (Note that your host system may not be able
3926 to achieve all of these rates.)
3930 The i960 configuration now includes an initial implementation of a
3931 builtin simulator, contributed by Jim Wilson.
3934 *** Changes in GDB-4.17:
3936 * New native configurations
3938 Alpha GNU/Linux alpha*-*-linux*
3939 Unixware 2.x i[3456]86-unixware2*
3940 Irix 6.x mips*-sgi-irix6*
3941 PowerPC GNU/Linux powerpc-*-linux*
3942 PowerPC Solaris powerpcle-*-solaris*
3943 Sparc GNU/Linux sparc-*-linux*
3944 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3948 Argonaut Risc Chip (ARC) arc-*-*
3949 Hitachi H8/300S h8300*-*-*
3950 Matsushita MN10200 w/simulator mn10200-*-*
3951 Matsushita MN10300 w/simulator mn10300-*-*
3952 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3953 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3954 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3955 Mitsubishi D10V w/simulator d10v-*-*
3956 Mitsubishi M32R/D w/simulator m32r-*-elf*
3957 Tsqware Sparclet sparclet-*-*
3958 NEC V850 w/simulator v850-*-*
3960 * New debugging protocols
3962 ARM with RDI protocol arm*-*-*
3963 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3964 DDB and LSI variants of PMON protocol mips*-*-*
3965 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3966 PowerPC with SDS protocol powerpc{,le}-*-eabi
3967 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3971 All configurations can now understand and use the DWARF 2 debugging
3972 format. The choice is automatic, if the symbol file contains DWARF 2
3977 GDB now includes basic Java language support. This support is
3978 only useful with Java compilers that produce native machine code.
3980 * solib-absolute-prefix and solib-search-path
3982 For SunOS and SVR4 shared libraries, you may now set the prefix for
3983 loading absolute shared library symbol files, and the search path for
3984 locating non-absolute shared library symbol files.
3986 * Live range splitting
3988 GDB can now effectively debug code for which GCC has performed live
3989 range splitting as part of its optimization. See gdb/doc/LRS for
3990 more details on the expected format of the stabs information.
3994 GDB's support for the GNU Hurd, including thread debugging, has been
3995 updated to work with current versions of the Hurd.
3999 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4000 instruction set. ARM GDB automatically detects when Thumb
4001 instructions are in use, and adjusts disassembly and backtracing
4006 GDB's MIPS target configurations now handle the MIP16 16-bit
4011 GDB now includes support for overlays; if an executable has been
4012 linked such that multiple sections are based at the same address, GDB
4013 will decide which section to use for symbolic info. You can choose to
4014 control the decision manually, using overlay commands, or implement
4015 additional target-side support and use "overlay load-target" to bring
4016 in the overlay mapping. Do "help overlay" for more detail.
4020 The command "info symbol <address>" displays information about
4021 the symbol at the specified address.
4025 The standard remote protocol now includes an extension that allows
4026 asynchronous collection and display of trace data. This requires
4027 extensive support in the target-side debugging stub. Tracing mode
4028 includes a new interaction mode in GDB and new commands: see the
4029 file tracepoint.c for more details.
4033 Configurations for embedded MIPS now include a simulator contributed
4034 by Cygnus Solutions. The simulator supports the instruction sets
4035 of most MIPS variants.
4039 Sparc configurations may now include the ERC32 simulator contributed
4040 by the European Space Agency. The simulator is not built into
4041 Sparc targets by default; configure with --enable-sim to include it.
4045 For target configurations that may include multiple variants of a
4046 basic architecture (such as MIPS and SH), you may now set the
4047 architecture explicitly. "set arch" sets, "info arch" lists
4048 the possible architectures.
4050 *** Changes in GDB-4.16:
4052 * New native configurations
4054 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4055 M68K NetBSD m68k-*-netbsd*
4056 PowerPC AIX 4.x powerpc-*-aix*
4057 PowerPC MacOS powerpc-*-macos*
4058 PowerPC Windows NT powerpcle-*-cygwin32
4059 RS/6000 AIX 4.x rs6000-*-aix4*
4063 ARM with RDP protocol arm-*-*
4064 I960 with MON960 i960-*-coff
4065 MIPS VxWorks mips*-*-vxworks*
4066 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4067 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4069 Matra Sparclet sparclet-*-*
4073 The powerpc-eabi configuration now includes the PSIM simulator,
4074 contributed by Andrew Cagney, with assistance from Mike Meissner.
4075 PSIM is a very elaborate model of the PowerPC, including not only
4076 basic instruction set execution, but also details of execution unit
4077 performance and I/O hardware. See sim/ppc/README for more details.
4081 GDB now works with Solaris 2.5.
4083 * Windows 95/NT native
4085 GDB will now work as a native debugger on Windows 95 and Windows NT.
4086 To build it from source, you must use the "gnu-win32" environment,
4087 which uses a DLL to emulate enough of Unix to run the GNU tools.
4088 Further information, binaries, and sources are available at
4089 ftp.cygnus.com, under pub/gnu-win32.
4091 * dont-repeat command
4093 If a user-defined command includes the command `dont-repeat', then the
4094 command will not be repeated if the user just types return. This is
4095 useful if the command is time-consuming to run, so that accidental
4096 extra keystrokes don't run the same command many times.
4098 * Send break instead of ^C
4100 The standard remote protocol now includes an option to send a break
4101 rather than a ^C to the target in order to interrupt it. By default,
4102 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4104 * Remote protocol timeout
4106 The standard remote protocol includes a new variable `remotetimeout'
4107 that allows you to set the number of seconds before GDB gives up trying
4108 to read from the target. The default value is 2.
4110 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4112 By default GDB will automatically keep track of objects as they are
4113 loaded and unloaded by the dynamic linker. By using the command `set
4114 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4115 when shared library events occur, thus allowing you to set breakpoints
4116 in shared libraries which are explicitly loaded by the inferior.
4118 Note this feature does not work on hpux8. On hpux9 you must link
4119 /usr/lib/end.o into your program. This feature should work
4120 automatically on hpux10.
4122 * Irix 5.x hardware watchpoint support
4124 Irix 5 configurations now support the use of hardware watchpoints.
4126 * Mips protocol "SYN garbage limit"
4128 When debugging a Mips target using the `target mips' protocol, you
4129 may set the number of characters that GDB will ignore by setting
4130 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4131 every character. The default value is 1050.
4133 * Recording and replaying remote debug sessions
4135 If you set `remotelogfile' to the name of a file, gdb will write to it
4136 a recording of a remote debug session. This recording may then be
4137 replayed back to gdb using "gdbreplay". See gdbserver/README for
4138 details. This is useful when you have a problem with GDB while doing
4139 remote debugging; you can make a recording of the session and send it
4140 to someone else, who can then recreate the problem.
4142 * Speedups for remote debugging
4144 GDB includes speedups for downloading and stepping MIPS systems using
4145 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4146 and more efficient S-record downloading.
4148 * Memory use reductions and statistics collection
4150 GDB now uses less memory and reports statistics about memory usage.
4151 Try the `maint print statistics' command, for example.
4153 *** Changes in GDB-4.15:
4155 * Psymtabs for XCOFF
4157 The symbol reader for AIX GDB now uses partial symbol tables. This
4158 can greatly improve startup time, especially for large executables.
4160 * Remote targets use caching
4162 Remote targets now use a data cache to speed up communication with the
4163 remote side. The data cache could lead to incorrect results because
4164 it doesn't know about volatile variables, thus making it impossible to
4165 debug targets which use memory mapped I/O devices. `set remotecache
4166 off' turns the the data cache off.
4168 * Remote targets may have threads
4170 The standard remote protocol now includes support for multiple threads
4171 in the target system, using new protocol commands 'H' and 'T'. See
4172 gdb/remote.c for details.
4176 If GDB is configured with `--enable-netrom', then it will include
4177 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4178 acts as though it is a bank of ROM on the target board, but you can
4179 write into it over the network. GDB's support consists only of
4180 support for fast loading into the emulated ROM; to debug, you must use
4181 another protocol, such as standard remote protocol. The usual
4182 sequence is something like
4184 target nrom <netrom-hostname>
4186 target remote <netrom-hostname>:1235
4190 GDB now includes support for the Apple Macintosh, as a host only. It
4191 may be run as either an MPW tool or as a standalone application, and
4192 it can debug through the serial port. All the usual GDB commands are
4193 available, but to the target command, you must supply "serial" as the
4194 device type instead of "/dev/ttyXX". See mpw-README in the main
4195 directory for more information on how to build. The MPW configuration
4196 scripts */mpw-config.in support only a few targets, and only the
4197 mips-idt-ecoff target has been tested.
4201 GDB configuration now uses autoconf. This is not user-visible,
4202 but does simplify configuration and building.
4206 GDB now supports hpux10.
4208 *** Changes in GDB-4.14:
4210 * New native configurations
4212 x86 FreeBSD i[345]86-*-freebsd
4213 x86 NetBSD i[345]86-*-netbsd
4214 NS32k NetBSD ns32k-*-netbsd
4215 Sparc NetBSD sparc-*-netbsd
4219 A29K VxWorks a29k-*-vxworks
4220 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4221 CPU32 EST-300 emulator m68*-*-est*
4222 PowerPC ELF powerpc-*-elf
4225 * Alpha OSF/1 support for procfs
4227 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4228 possible to attach to running processes. As the mounting of the /proc
4229 filesystem is optional on the Alpha, GDB automatically determines
4230 the availability of /proc during startup. This can lead to problems
4231 if /proc is unmounted after GDB has been started.
4233 * Arguments to user-defined commands
4235 User commands may accept up to 10 arguments separated by whitespace.
4236 Arguments are accessed within the user command via $arg0..$arg9. A
4239 print $arg0 + $arg1 + $arg2
4241 To execute the command use:
4244 Defines the command "adder" which prints the sum of its three arguments.
4245 Note the arguments are text substitutions, so they may reference variables,
4246 use complex expressions, or even perform inferior function calls.
4248 * New `if' and `while' commands
4250 This makes it possible to write more sophisticated user-defined
4251 commands. Both commands take a single argument, which is the
4252 expression to evaluate, and must be followed by the commands to
4253 execute, one per line, if the expression is nonzero, the list being
4254 terminated by the word `end'. The `if' command list may include an
4255 `else' word, which causes the following commands to be executed only
4256 if the expression is zero.
4258 * Fortran source language mode
4260 GDB now includes partial support for Fortran 77. It will recognize
4261 Fortran programs and can evaluate a subset of Fortran expressions, but
4262 variables and functions may not be handled correctly. GDB will work
4263 with G77, but does not yet know much about symbols emitted by other
4266 * Better HPUX support
4268 Most debugging facilities now work on dynamic executables for HPPAs
4269 running hpux9 or later. You can attach to running dynamically linked
4270 processes, but by default the dynamic libraries will be read-only, so
4271 for instance you won't be able to put breakpoints in them. To change
4272 that behavior do the following before running the program:
4278 This will cause the libraries to be mapped private and read-write.
4279 To revert to the normal behavior, do this:
4285 You cannot set breakpoints or examine data in the library until after
4286 the library is loaded if the function/data symbols do not have
4289 GDB can now also read debug symbols produced by the HP C compiler on
4290 HPPAs (sorry, no C++, Fortran or 68k support).
4292 * Target byte order now dynamically selectable
4294 You can choose which byte order to use with a target system, via the
4295 commands "set endian big" and "set endian little", and you can see the
4296 current setting by using "show endian". You can also give the command
4297 "set endian auto", in which case GDB will use the byte order
4298 associated with the executable. Currently, only embedded MIPS
4299 configurations support dynamic selection of target byte order.
4301 * New DOS host serial code
4303 This version uses DPMI interrupts to handle buffered I/O, so you
4304 no longer need to run asynctsr when debugging boards connected to
4307 *** Changes in GDB-4.13:
4309 * New "complete" command
4311 This lists all the possible completions for the rest of the line, if it
4312 were to be given as a command itself. This is intended for use by emacs.
4314 * Trailing space optional in prompt
4316 "set prompt" no longer adds a space for you after the prompt you set. This
4317 allows you to set a prompt which ends in a space or one that does not.
4319 * Breakpoint hit counts
4321 "info break" now displays a count of the number of times the breakpoint
4322 has been hit. This is especially useful in conjunction with "ignore"; you
4323 can ignore a large number of breakpoint hits, look at the breakpoint info
4324 to see how many times the breakpoint was hit, then run again, ignoring one
4325 less than that number, and this will get you quickly to the last hit of
4328 * Ability to stop printing at NULL character
4330 "set print null-stop" will cause GDB to stop printing the characters of
4331 an array when the first NULL is encountered. This is useful when large
4332 arrays actually contain only short strings.
4334 * Shared library breakpoints
4336 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4337 breakpoints in shared libraries before the executable is run.
4339 * Hardware watchpoints
4341 There is a new hardware breakpoint for the watch command for sparclite
4342 targets. See gdb/sparclite/hw_breakpoint.note.
4344 Hardware watchpoints are also now supported under GNU/Linux.
4348 Annotations have been added. These are for use with graphical interfaces,
4349 and are still experimental. Currently only gdba.el uses these.
4351 * Improved Irix 5 support
4353 GDB now works properly with Irix 5.2.
4355 * Improved HPPA support
4357 GDB now works properly with the latest GCC and GAS.
4359 * New native configurations
4361 Sequent PTX4 i[34]86-sequent-ptx4
4362 HPPA running OSF/1 hppa*-*-osf*
4363 Atari TT running SVR4 m68*-*-sysv4*
4364 RS/6000 LynxOS rs6000-*-lynxos*
4368 OS/9000 i[34]86-*-os9k
4369 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4372 * Hitachi SH7000 and E7000-PC ICE support
4374 There is now support for communicating with the Hitachi E7000-PC ICE.
4375 This is available automatically when GDB is configured for the SH.
4379 As usual, a variety of small fixes and improvements, both generic
4380 and configuration-specific. See the ChangeLog for more detail.
4382 *** Changes in GDB-4.12:
4384 * Irix 5 is now supported
4388 GDB-4.12 on the HPPA has a number of changes which make it unable
4389 to debug the output from the currently released versions of GCC and
4390 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4391 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4392 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4395 *** Changes in GDB-4.11:
4397 * User visible changes:
4401 The "set remotedebug" option is now consistent between the mips remote
4402 target, remote targets using the gdb-specific protocol, UDI (AMD's
4403 debug protocol for the 29k) and the 88k bug monitor. It is now an
4404 integer specifying a debug level (normally 0 or 1, but 2 means more
4405 debugging info for the mips target).
4407 * DEC Alpha native support
4409 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4410 debug info, but GDB works fairly well with the DEC compiler and should
4411 work with a future GCC release. See the README file for a few
4412 Alpha-specific notes.
4414 * Preliminary thread implementation
4416 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4418 * LynxOS native and target support for 386
4420 This release has been hosted on LynxOS 2.2, and also can be configured
4421 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4424 * Improvements in C++ mangling/demangling.
4426 This release has much better g++ debugging, specifically in name
4427 mangling/demangling, virtual function calls, print virtual table,
4428 call methods, ...etc.
4430 *** Changes in GDB-4.10:
4432 * User visible changes:
4434 Remote debugging using the GDB-specific (`target remote') protocol now
4435 supports the `load' command. This is only useful if you have some
4436 other way of getting the stub to the target system, and you can put it
4437 somewhere in memory where it won't get clobbered by the download.
4439 Filename completion now works.
4441 When run under emacs mode, the "info line" command now causes the
4442 arrow to point to the line specified. Also, "info line" prints
4443 addresses in symbolic form (as well as hex).
4445 All vxworks based targets now support a user settable option, called
4446 vxworks-timeout. This option represents the number of seconds gdb
4447 should wait for responses to rpc's. You might want to use this if
4448 your vxworks target is, perhaps, a slow software simulator or happens
4449 to be on the far side of a thin network line.
4453 This release contains support for using a DEC alpha as a GDB host for
4454 cross debugging. Native alpha debugging is not supported yet.
4457 *** Changes in GDB-4.9:
4461 This is the first GDB release which is accompanied by a matching testsuite.
4462 The testsuite requires installation of dejagnu, which should be available
4463 via ftp from most sites that carry GNU software.
4467 'Cfront' style demangling has had its name changed to 'ARM' style, to
4468 emphasize that it was written from the specifications in the C++ Annotated
4469 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4470 disclaimers, it still generated too much confusion with users attempting to
4471 use gdb with AT&T cfront.
4475 GDB now uses a standard remote interface to a simulator library.
4476 So far, the library contains simulators for the Zilog Z8001/2, the
4477 Hitachi H8/300, H8/500 and Super-H.
4479 * New targets supported
4481 H8/300 simulator h8300-hitachi-hms or h8300hms
4482 H8/500 simulator h8500-hitachi-hms or h8500hms
4483 SH simulator sh-hitachi-hms or sh
4484 Z8000 simulator z8k-zilog-none or z8ksim
4485 IDT MIPS board over serial line mips-idt-ecoff
4487 Cross-debugging to GO32 targets is supported. It requires a custom
4488 version of the i386-stub.c module which is integrated with the
4489 GO32 memory extender.
4491 * New remote protocols
4493 MIPS remote debugging protocol.
4495 * New source languages supported
4497 This version includes preliminary support for Chill, a Pascal like language
4498 used by telecommunications companies. Chill support is also being integrated
4499 into the GNU compiler, but we don't know when it will be publically available.
4502 *** Changes in GDB-4.8:
4504 * HP Precision Architecture supported
4506 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4507 version of this support was available as a set of patches from the
4508 University of Utah. GDB does not support debugging of programs
4509 compiled with the HP compiler, because HP will not document their file
4510 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4511 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4513 Many problems in the preliminary version have been fixed.
4515 * Faster and better demangling
4517 We have improved template demangling and fixed numerous bugs in the GNU style
4518 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4519 character types (wchar_t) are now supported. Demangling of each symbol is now
4520 only done once, and is cached when the symbol table for a file is read in.
4521 This results in a small increase in memory usage for C programs, a moderate
4522 increase in memory usage for C++ programs, and a fantastic speedup in
4525 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4526 from the specifications in the Annotated Reference Manual, which AT&T's
4527 compiler does not actually implement.
4529 * G++ multiple inheritance compiler problem
4531 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4532 inheritance lattices was reworked to properly discover ambiguities. We
4533 recently found an example which causes this new algorithm to fail in a
4534 very subtle way, producing bad debug information for those classes.
4535 The file 'gcc.patch' (in this directory) can be applied to gcc to
4536 circumvent the problem. A future GCC release will contain a complete
4539 The previous G++ debug info problem (mentioned below for the gdb-4.7
4540 release) is fixed in gcc version 2.3.2.
4542 * Improved configure script
4544 The `configure' script will now attempt to guess your system type if
4545 you don't supply a host system type. The old scheme of supplying a
4546 host system triplet is preferable over using this. All the magic is
4547 done in the new `config.guess' script. Examine it for details.
4549 We have also brought our configure script much more in line with the FSF's
4550 version. It now supports the --with-xxx options. In particular,
4551 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4552 The resulting GDB will not be able to read arbitrary object file formats --
4553 only the format ``expected'' to be used on the configured target system.
4554 We hope to make this the default in a future release.
4556 * Documentation improvements
4558 There's new internal documentation on how to modify GDB, and how to
4559 produce clean changes to the code. We implore people to read it
4560 before submitting changes.
4562 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4563 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4564 `info' files are also provided. To build `info' files from scratch,
4565 you will need the latest `makeinfo' release, which will be available in
4566 a future texinfo-X.Y release.
4568 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4569 We're not sure exactly which versions have this problem, but it has
4570 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4571 or better. If that isn't possible, there is a patch in
4572 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4573 around this problem.
4577 GDB now supports array constants that can be used in expressions typed in by
4578 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4579 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4582 The new directory `gdb/sparclite' contains a program that demonstrates
4583 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4585 * New native hosts supported
4587 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4588 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4590 * New targets supported
4592 AMD 29k family via UDI a29k-amd-udi or udi29k
4594 * New file formats supported
4596 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4597 HPUX core files, and SCO 3.2v2 core files.
4601 Attaching to processes now works again; thanks for the many bug reports.
4603 We have also stomped on a bunch of core dumps caused by
4604 printf_filtered("%s") problems.
4606 We eliminated a copyright problem on the rpc and ptrace header files
4607 for VxWorks, which was discovered at the last minute during the 4.7
4608 release. You should now be able to build a VxWorks GDB.
4610 You can now interrupt gdb while an attached process is running. This
4611 will cause the attached process to stop, and give control back to GDB.
4613 We fixed problems caused by using too many file descriptors
4614 for reading symbols from object files and libraries. This was
4615 especially a problem for programs that used many (~100) shared
4618 The `step' command now only enters a subroutine if there is line number
4619 information for the subroutine. Otherwise it acts like the `next'
4620 command. Previously, `step' would enter subroutines if there was
4621 any debugging information about the routine. This avoids problems
4622 when using `cc -g1' on MIPS machines.
4624 * Internal improvements
4626 GDB's internal interfaces have been improved to make it easier to support
4627 debugging of multiple languages in the future.
4629 GDB now uses a common structure for symbol information internally.
4630 Minimal symbols (derived from linkage symbols in object files), partial
4631 symbols (from a quick scan of debug information), and full symbols
4632 contain a common subset of information, making it easier to write
4633 shared code that handles any of them.
4635 * New command line options
4637 We now accept --silent as an alias for --quiet.
4641 The memory-mapped-malloc library is now licensed under the GNU Library
4642 General Public License.
4644 *** Changes in GDB-4.7:
4646 * Host/native/target split
4648 GDB has had some major internal surgery to untangle the support for
4649 hosts and remote targets. Now, when you configure GDB for a remote
4650 target, it will no longer load in all of the support for debugging
4651 local programs on the host. When fully completed and tested, this will
4652 ensure that arbitrary host/target combinations are possible.
4654 The primary conceptual shift is to separate the non-portable code in
4655 GDB into three categories. Host specific code is required any time GDB
4656 is compiled on that host, regardless of the target. Target specific
4657 code relates to the peculiarities of the target, but can be compiled on
4658 any host. Native specific code is everything else: it can only be
4659 built when the host and target are the same system. Child process
4660 handling and core file support are two common `native' examples.
4662 GDB's use of /proc for controlling Unix child processes is now cleaner.
4663 It has been split out into a single module under the `target_ops' vector,
4664 plus two native-dependent functions for each system that uses /proc.
4666 * New hosts supported
4668 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4669 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4670 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4672 * New targets supported
4674 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4675 68030 and CPU32 m68030-*-*, m68332-*-*
4677 * New native hosts supported
4679 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4680 (386bsd is not well tested yet)
4681 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4683 * New file formats supported
4685 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4686 supports reading of `a.out.adobe' object files, which are an a.out
4687 format extended with minimal information about multiple sections.
4691 `show copying' is the same as the old `info copying'.
4692 `show warranty' is the same as `info warrantee'.
4693 These were renamed for consistency. The old commands continue to work.
4695 `info handle' is a new alias for `info signals'.
4697 You can now define pre-command hooks, which attach arbitrary command
4698 scripts to any command. The commands in the hook will be executed
4699 prior to the user's command. You can also create a hook which will be
4700 executed whenever the program stops. See gdb.texinfo.
4704 We now deal with Cfront style name mangling, and can even extract type
4705 info from mangled symbols. GDB can automatically figure out which
4706 symbol mangling style your C++ compiler uses.
4708 Calling of methods and virtual functions has been improved as well.
4712 The crash that occured when debugging Sun Ansi-C compiled binaries is
4713 fixed. This was due to mishandling of the extra N_SO stabs output
4716 We also finally got Ultrix 4.2 running in house, and fixed core file
4717 support, with help from a dozen people on the net.
4719 John M. Farrell discovered that the reason that single-stepping was so
4720 slow on all of the Mips based platforms (primarily SGI and DEC) was
4721 that we were trying to demangle and lookup a symbol used for internal
4722 purposes on every instruction that was being stepped through. Changing
4723 the name of that symbol so that it couldn't be mistaken for a C++
4724 mangled symbol sped things up a great deal.
4726 Rich Pixley sped up symbol lookups in general by getting much smarter
4727 about when C++ symbol mangling is necessary. This should make symbol
4728 completion (TAB on the command line) much faster. It's not as fast as
4729 we'd like, but it's significantly faster than gdb-4.6.
4733 A new user controllable variable 'call_scratch_address' can
4734 specify the location of a scratch area to be used when GDB
4735 calls a function in the target. This is necessary because the
4736 usual method of putting the scratch area on the stack does not work
4737 in systems that have separate instruction and data spaces.
4739 We integrated changes to support the 29k UDI (Universal Debugger
4740 Interface), but discovered at the last minute that we didn't have all
4741 of the appropriate copyright paperwork. We are working with AMD to
4742 resolve this, and hope to have it available soon.
4746 We have sped up the remote serial line protocol, especially for targets
4747 with lots of registers. It now supports a new `expedited status' ('T')
4748 message which can be used in place of the existing 'S' status message.
4749 This allows the remote stub to send only the registers that GDB
4750 needs to make a quick decision about single-stepping or conditional
4751 breakpoints, eliminating the need to fetch the entire register set for
4752 each instruction being stepped through.
4754 The GDB remote serial protocol now implements a write-through cache for
4755 registers, only re-reading the registers if the target has run.
4757 There is also a new remote serial stub for SPARC processors. You can
4758 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4759 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4760 processor with a serial port.
4764 Configure.in files have become much easier to read and modify. A new
4765 `table driven' format makes it more obvious what configurations are
4766 supported, and what files each one uses.
4770 There is a new opcodes library which will eventually contain all of the
4771 disassembly routines and opcode tables. At present, it only contains
4772 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4773 disassembler (binutils/objdump) to share these routines.
4775 The libiberty library is now copylefted under the GNU Library General
4776 Public License. This allows more liberal use, and was done so libg++
4777 can use it. This makes no difference to GDB, since the Library License
4778 grants all the rights from the General Public License.
4782 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4783 reference to the stabs symbol info used by the debugger. It is (as far
4784 as we know) the only published document on this fascinating topic. We
4785 encourage you to read it, compare it to the stabs information on your
4786 system, and send improvements on the document in general (to
4787 bug-gdb@prep.ai.mit.edu).
4789 And, of course, many bugs have been fixed.
4792 *** Changes in GDB-4.6:
4794 * Better support for C++ function names
4796 GDB now accepts as input the "demangled form" of C++ overloaded function
4797 names and member function names, and can do command completion on such names
4798 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4799 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4800 Make use of command completion, it is your friend.
4802 GDB also now accepts a variety of C++ mangled symbol formats. They are
4803 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4804 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4805 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4806 for the list of formats.
4808 * G++ symbol mangling problem
4810 Recent versions of gcc have a bug in how they emit debugging information for
4811 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4812 directory) can be applied to gcc to fix the problem. Alternatively, if you
4813 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4814 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4815 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4818 * New 'maintenance' command
4820 All of the commands related to hacking GDB internals have been moved out of
4821 the main command set, and now live behind the 'maintenance' command. This
4822 can also be abbreviated as 'mt'. The following changes were made:
4824 dump-me -> maintenance dump-me
4825 info all-breakpoints -> maintenance info breakpoints
4826 printmsyms -> maintenance print msyms
4827 printobjfiles -> maintenance print objfiles
4828 printpsyms -> maintenance print psymbols
4829 printsyms -> maintenance print symbols
4831 The following commands are new:
4833 maintenance demangle Call internal GDB demangler routine to
4834 demangle a C++ link name and prints the result.
4835 maintenance print type Print a type chain for a given symbol
4837 * Change to .gdbinit file processing
4839 We now read the $HOME/.gdbinit file before processing the argv arguments
4840 (e.g. reading symbol files or core files). This allows global parameters to
4841 be set, which will apply during the symbol reading. The ./.gdbinit is still
4842 read after argv processing.
4844 * New hosts supported
4846 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4848 GNU/Linux support i386-unknown-linux or linux
4850 We are also including code to support the HP/PA running BSD and HPUX. This
4851 is almost guaranteed not to work, as we didn't have time to test or build it
4852 for this release. We are including it so that the more adventurous (or
4853 masochistic) of you can play with it. We also had major problems with the
4854 fact that the compiler that we got from HP doesn't support the -g option.
4857 * New targets supported
4859 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4861 * More smarts about finding #include files
4863 GDB now remembers the compilation directory for all include files, and for
4864 all files from which C is generated (like yacc and lex sources). This
4865 greatly improves GDB's ability to find yacc/lex sources, and include files,
4866 especially if you are debugging your program from a directory different from
4867 the one that contains your sources.
4869 We also fixed a bug which caused difficulty with listing and setting
4870 breakpoints in include files which contain C code. (In the past, you had to
4871 try twice in order to list an include file that you hadn't looked at before.)
4873 * Interesting infernals change
4875 GDB now deals with arbitrary numbers of sections, where the symbols for each
4876 section must be relocated relative to that section's landing place in the
4877 target's address space. This work was needed to support ELF with embedded
4878 stabs used by Solaris-2.0.
4880 * Bug fixes (of course!)
4882 There have been loads of fixes for the following things:
4883 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4884 i960, stabs, DOS(GO32), procfs, etc...
4886 See the ChangeLog for details.
4888 *** Changes in GDB-4.5:
4890 * New machines supported (host and target)
4892 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4894 SGI Irix-4.x mips-sgi-irix4 or iris4
4896 * New malloc package
4898 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4899 Mmalloc is capable of handling mutiple heaps of memory. It is also
4900 capable of saving a heap to a file, and then mapping it back in later.
4901 This can be used to greatly speedup the startup of GDB by using a
4902 pre-parsed symbol table which lives in a mmalloc managed heap. For
4903 more details, please read mmalloc/mmalloc.texi.
4907 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4908 'help info proc' for details.
4910 * MIPS ecoff symbol table format
4912 The code that reads MIPS symbol table format is now supported on all hosts.
4913 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4916 * File name changes for MS-DOS
4918 Many files in the config directories have been renamed to make it easier to
4919 support GDB on MS-DOSe systems (which have very restrictive file name
4920 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4921 environment) is close to working but has some remaining problems. Note
4922 that debugging of DOS programs is not supported, due to limitations
4923 in the ``operating system'', but it can be used to host cross-debugging.
4925 * Cross byte order fixes
4927 Many fixes have been made to support cross debugging of Sparc and MIPS
4928 targets from hosts whose byte order differs.
4930 * New -mapped and -readnow options
4932 If memory-mapped files are available on your system through the 'mmap'
4933 system call, you can use the -mapped option on the `file' or
4934 `symbol-file' commands to cause GDB to write the symbols from your
4935 program into a reusable file. If the program you are debugging is
4936 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4937 Future GDB debugging sessions will notice the presence of this file,
4938 and will quickly map in symbol information from it, rather than reading
4939 the symbol table from the executable program. Using the '-mapped'
4940 option in a GDB `file' or `symbol-file' command has the same effect as
4941 starting GDB with the '-mapped' command-line option.
4943 You can cause GDB to read the entire symbol table immediately by using
4944 the '-readnow' option with any of the commands that load symbol table
4945 information (or on the GDB command line). This makes the command
4946 slower, but makes future operations faster.
4948 The -mapped and -readnow options are typically combined in order to
4949 build a `fred.syms' file that contains complete symbol information.
4950 A simple GDB invocation to do nothing but build a `.syms' file for future
4953 gdb -batch -nx -mapped -readnow programname
4955 The `.syms' file is specific to the host machine on which GDB is run.
4956 It holds an exact image of GDB's internal symbol table. It cannot be
4957 shared across multiple host platforms.
4959 * longjmp() handling
4961 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4962 siglongjmp() without losing control. This feature has not yet been ported to
4963 all systems. It currently works on many 386 platforms, all MIPS-based
4964 platforms (SGI, DECstation, etc), and Sun3/4.
4968 Preliminary work has been put in to support the new Solaris OS from Sun. At
4969 this time, it can control and debug processes, but it is not capable of
4974 As always, many many bug fixes. The major areas were with g++, and mipsread.
4975 People using the MIPS-based platforms should experience fewer mysterious
4976 crashes and trashed symbol tables.
4978 *** Changes in GDB-4.4:
4980 * New machines supported (host and target)
4982 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4984 BSD Reno on Vax vax-dec-bsd
4985 Ultrix on Vax vax-dec-ultrix
4987 * New machines supported (target)
4989 AMD 29000 embedded, using EBMON a29k-none-none
4993 GDB continues to improve its handling of C++. `References' work better.
4994 The demangler has also been improved, and now deals with symbols mangled as
4995 per the Annotated C++ Reference Guide.
4997 GDB also now handles `stabs' symbol information embedded in MIPS
4998 `ecoff' symbol tables. Since the ecoff format was not easily
4999 extensible to handle new languages such as C++, this appeared to be a
5000 good way to put C++ debugging info into MIPS binaries. This option
5001 will be supported in the GNU C compiler, version 2, when it is
5004 * New features for SVR4
5006 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5007 shared libraries. Debugging dynamically linked programs should present
5008 only minor differences from debugging statically linked programs.
5010 The `info proc' command will print out information about any process
5011 on an SVR4 system (including the one you are debugging). At the moment,
5012 it prints the address mappings of the process.
5014 If you bring up GDB on another SVR4 system, please send mail to
5015 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5017 * Better dynamic linking support in SunOS
5019 Reading symbols from shared libraries which contain debugging symbols
5020 now works properly. However, there remain issues such as automatic
5021 skipping of `transfer vector' code during function calls, which
5022 make it harder to debug code in a shared library, than to debug the
5023 same code linked statically.
5027 GDB is now using the latest `getopt' routines from the FSF. This
5028 version accepts the -- prefix for options with long names. GDB will
5029 continue to accept the old forms (-option and +option) as well.
5030 Various single letter abbreviations for options have been explicity
5031 added to the option table so that they won't get overshadowed in the
5032 future by other options that begin with the same letter.
5036 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5037 Many assorted bugs have been handled. Many more remain to be handled.
5038 See the various ChangeLog files (primarily in gdb and bfd) for details.
5041 *** Changes in GDB-4.3:
5043 * New machines supported (host and target)
5045 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5046 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5047 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5049 * Almost SCO Unix support
5051 We had hoped to support:
5052 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5053 (except for core file support), but we discovered very late in the release
5054 that it has problems with process groups that render gdb unusable. Sorry
5055 about that. I encourage people to fix it and post the fixes.
5057 * Preliminary ELF and DWARF support
5059 GDB can read ELF object files on System V Release 4, and can handle
5060 debugging records for C, in DWARF format, in ELF files. This support
5061 is preliminary. If you bring up GDB on another SVR4 system, please
5062 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5067 GDB now uses the latest `readline' library. One user-visible change
5068 is that two tabs will list possible command completions, which previously
5069 required typing M-? (meta-question mark, or ESC ?).
5073 The `stepi' bug that many of you noticed has been squashed.
5074 Many bugs in C++ have been handled. Many more remain to be handled.
5075 See the various ChangeLog files (primarily in gdb and bfd) for details.
5077 * State of the MIPS world (in case you wondered):
5079 GDB can understand the symbol tables emitted by the compilers
5080 supplied by most vendors of MIPS-based machines, including DEC. These
5081 symbol tables are in a format that essentially nobody else uses.
5083 Some versions of gcc come with an assembler post-processor called
5084 mips-tfile. This program is required if you want to do source-level
5085 debugging of gcc-compiled programs. I believe FSF does not ship
5086 mips-tfile with gcc version 1, but it will eventually come with gcc
5089 Debugging of g++ output remains a problem. g++ version 1.xx does not
5090 really support it at all. (If you're lucky, you should be able to get
5091 line numbers and stack traces to work, but no parameters or local
5092 variables.) With some work it should be possible to improve the
5095 When gcc version 2 is released, you will have somewhat better luck.
5096 However, even then you will get confusing results for inheritance and
5099 We will eventually provide full debugging of g++ output on
5100 DECstations. This will probably involve some kind of stabs-in-ecoff
5101 encapulation, but the details have not been worked out yet.
5104 *** Changes in GDB-4.2:
5106 * Improved configuration
5108 Only one copy of `configure' exists now, and it is not self-modifying.
5109 Porting BFD is simpler.
5113 The `step' and `next' commands now only stop at the first instruction
5114 of a source line. This prevents the multiple stops that used to occur
5115 in switch statements, for-loops, etc. `Step' continues to stop if a
5116 function that has debugging information is called within the line.
5120 Lots of small bugs fixed. More remain.
5122 * New host supported (not target)
5124 Intel 386 PC clone running Mach i386-none-mach
5127 *** Changes in GDB-4.1:
5129 * Multiple source language support
5131 GDB now has internal scaffolding to handle several source languages.
5132 It determines the type of each source file from its filename extension,
5133 and will switch expression parsing and number formatting to match the
5134 language of the function in the currently selected stack frame.
5135 You can also specifically set the language to be used, with
5136 `set language c' or `set language modula-2'.
5140 GDB now has preliminary support for the GNU Modula-2 compiler,
5141 currently under development at the State University of New York at
5142 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5143 continue through the fall of 1991 and into 1992.
5145 Other Modula-2 compilers are currently not supported, and attempting to
5146 debug programs compiled with them will likely result in an error as the
5147 symbol table is read. Feel free to work on it, though!
5149 There are hooks in GDB for strict type checking and range checking,
5150 in the `Modula-2 philosophy', but they do not currently work.
5154 GDB can now write to executable and core files (e.g. patch
5155 a variable's value). You must turn this switch on, specify
5156 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5157 by assigning a new value to a variable. Modifications take
5160 * Automatic SunOS shared library reading
5162 When you run your program, GDB automatically determines where its
5163 shared libraries (if any) have been loaded, and reads their symbols.
5164 The `share' command is no longer needed. This also works when
5165 examining core files.
5169 You can specify the number of lines that the `list' command shows.
5172 * New machines supported (host and target)
5174 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5175 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5176 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5178 * New hosts supported (not targets)
5180 IBM RT/PC: romp-ibm-aix or rtpc
5182 * New targets supported (not hosts)
5184 AMD 29000 embedded with COFF a29k-none-coff
5185 AMD 29000 embedded with a.out a29k-none-aout
5186 Ultracomputer remote kernel debug a29k-nyu-kern
5188 * New remote interfaces
5194 *** Changes in GDB-4.0:
5198 Wide output is wrapped at good places to make the output more readable.
5200 Gdb now supports cross-debugging from a host machine of one type to a
5201 target machine of another type. Communication with the target system
5202 is over serial lines. The ``target'' command handles connecting to the
5203 remote system; the ``load'' command will download a program into the
5204 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5205 also supports debugging of realtime processes running under VxWorks,
5206 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5207 stub on the target system.
5209 New CPUs supported include the AMD 29000 and Intel 960.
5211 GDB now reads object files and symbol tables via a ``binary file''
5212 library, which allows a single copy of GDB to debug programs of multiple
5213 object file types such as a.out and coff.
5215 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5216 refcard.dvi and refcard.ps are available to format it).
5219 * Control-Variable user interface simplified
5221 All variables that control the operation of the debugger can be set
5222 by the ``set'' command, and displayed by the ``show'' command.
5224 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5225 ``Show prompt'' produces the response:
5226 Gdb's prompt is new-gdb=>.
5228 What follows are the NEW set commands. The command ``help set'' will
5229 print a complete list of old and new set commands. ``help set FOO''
5230 will give a longer description of the variable FOO. ``show'' will show
5231 all of the variable descriptions and their current settings.
5233 confirm on/off: Enables warning questions for operations that are
5234 hard to recover from, e.g. rerunning the program while
5235 it is already running. Default is ON.
5237 editing on/off: Enables EMACS style command line editing
5238 of input. Previous lines can be recalled with
5239 control-P, the current line can be edited with control-B,
5240 you can search for commands with control-R, etc.
5243 history filename NAME: NAME is where the gdb command history
5244 will be stored. The default is .gdb_history,
5245 or the value of the environment variable
5248 history size N: The size, in commands, of the command history. The
5249 default is 256, or the value of the environment variable
5252 history save on/off: If this value is set to ON, the history file will
5253 be saved after exiting gdb. If set to OFF, the
5254 file will not be saved. The default is OFF.
5256 history expansion on/off: If this value is set to ON, then csh-like
5257 history expansion will be performed on
5258 command line input. The default is OFF.
5260 radix N: Sets the default radix for input and output. It can be set
5261 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5262 in the current radix, so "set radix 10" is always a no-op.
5264 height N: This integer value is the number of lines on a page. Default
5265 is 24, the current `stty rows'' setting, or the ``li#''
5266 setting from the termcap entry matching the environment
5269 width N: This integer value is the number of characters on a line.
5270 Default is 80, the current `stty cols'' setting, or the ``co#''
5271 setting from the termcap entry matching the environment
5274 Note: ``set screensize'' is obsolete. Use ``set height'' and
5275 ``set width'' instead.
5277 print address on/off: Print memory addresses in various command displays,
5278 such as stack traces and structure values. Gdb looks
5279 more ``symbolic'' if you turn this off; it looks more
5280 ``machine level'' with it on. Default is ON.
5282 print array on/off: Prettyprint arrays. New convenient format! Default
5285 print demangle on/off: Print C++ symbols in "source" form if on,
5288 print asm-demangle on/off: Same, for assembler level printouts
5291 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5294 * Support for Epoch Environment.
5296 The epoch environment is a version of Emacs v18 with windowing. One
5297 new command, ``inspect'', is identical to ``print'', except that if you
5298 are running in the epoch environment, the value is printed in its own
5302 * Support for Shared Libraries
5304 GDB can now debug programs and core files that use SunOS shared libraries.
5305 Symbols from a shared library cannot be referenced
5306 before the shared library has been linked with the program (this
5307 happens after you type ``run'' and before the function main() is entered).
5308 At any time after this linking (including when examining core files
5309 from dynamically linked programs), gdb reads the symbols from each
5310 shared library when you type the ``sharedlibrary'' command.
5311 It can be abbreviated ``share''.
5313 sharedlibrary REGEXP: Load shared object library symbols for files
5314 matching a unix regular expression. No argument
5315 indicates to load symbols for all shared libraries.
5317 info sharedlibrary: Status of loaded shared libraries.
5322 A watchpoint stops execution of a program whenever the value of an
5323 expression changes. Checking for this slows down execution
5324 tremendously whenever you are in the scope of the expression, but is
5325 quite useful for catching tough ``bit-spreader'' or pointer misuse
5326 problems. Some machines such as the 386 have hardware for doing this
5327 more quickly, and future versions of gdb will use this hardware.
5329 watch EXP: Set a watchpoint (breakpoint) for an expression.
5331 info watchpoints: Information about your watchpoints.
5333 delete N: Deletes watchpoint number N (same as breakpoints).
5334 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5335 enable N: Re-enables watchpoint number N (same as breakpoints).
5338 * C++ multiple inheritance
5340 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5343 * C++ exception handling
5345 Gdb now supports limited C++ exception handling. Besides the existing
5346 ability to breakpoint on an exception handler, gdb can breakpoint on
5347 the raising of an exception (before the stack is peeled back to the
5350 catch FOO: If there is a FOO exception handler in the dynamic scope,
5351 set a breakpoint to catch exceptions which may be raised there.
5352 Multiple exceptions (``catch foo bar baz'') may be caught.
5354 info catch: Lists all exceptions which may be caught in the
5355 current stack frame.
5358 * Minor command changes
5360 The command ``call func (arg, arg, ...)'' now acts like the print
5361 command, except it does not print or save a value if the function's result
5362 is void. This is similar to dbx usage.
5364 The ``up'' and ``down'' commands now always print the frame they end up
5365 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5366 frames without printing.
5368 * New directory command
5370 'dir' now adds directories to the FRONT of the source search path.
5371 The path starts off empty. Source files that contain debug information
5372 about the directory in which they were compiled can be found even
5373 with an empty path; Sun CC and GCC include this information. If GDB can't
5374 find your source file in the current directory, type "dir .".
5376 * Configuring GDB for compilation
5378 For normal use, type ``./configure host''. See README or gdb.texinfo
5381 GDB now handles cross debugging. If you are remotely debugging between
5382 two different machines, type ``./configure host -target=targ''.
5383 Host is the machine where GDB will run; targ is the machine
5384 where the program that you are debugging will run.