1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.5
6 * New native configurations
8 FreeBSD/powerpc powerpc*-*-freebsd
12 Lynx 178 PowerPC powerpc-*-lynx*178
14 * If the configured location of system.gdbinit file (as given by the
15 --with-system-gdbinit option at configure time) is in the
16 data-directory (as specified by --with-gdb-datadir at configure
17 time) or in one of its subdirectories, then GDB will look for the
18 system-wide init file in the directory specified by the
19 --data-directory command-line option.
21 * New command line options:
23 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
24 other initialization files, unlike -nx which disables all of them.
26 * Removed command line options
28 -epoch This was used by the gdb mode in Epoch, an ancient fork of
31 * The 'ptype' and 'whatis' commands now accept an argument to control
34 * 'info proc' now works on some core files.
38 ** Vectors can be created with gdb.Type.vector.
40 ** Python's atexit.register now works in GDB.
42 ** Types can be pretty-printed via a Python API.
44 ** Python 3 is now supported (in addition to Python 2.4 or later)
46 ** New class gdb.Architecture exposes GDB's internal representation
47 of architecture in the Python API.
49 ** New method Frame.architecture returns the gdb.Architecture object
50 corresponding to the frame's architecture.
52 * New Python-based convenience functions:
54 ** $_memeq(buf1, buf2, length)
55 ** $_streq(str1, str2)
57 ** $_regex(str, regex)
59 * The 'cd' command now defaults to using '~' (the home directory) if not
62 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
63 default for GCC since November 2000.
65 * The command 'forward-search' can now be abbreviated as 'fo'.
67 * The command 'info tracepoints' can now display 'installed on target'
68 or 'not installed on target' for each non-pending location of tracepoint.
70 * New configure options
72 --enable-libmcheck/--disable-libmcheck
73 By default, development versions are built with -lmcheck on hosts
74 that support it, in order to help track memory corruption issues.
75 Release versions, on the other hand, are built without -lmcheck
76 by default. The --enable-libmcheck/--disable-libmcheck configure
77 options allow the user to override that default.
79 * New commands (for set/show, see "New options" below)
82 Catch signals. This is similar to "handle", but allows commands and
83 conditions to be attached.
86 List the BFDs known to GDB.
88 python-interactive [command]
90 Start a Python interactive prompt, or evaluate the optional command
91 and print the result of expressions.
94 "py" is a new alias for "python".
96 enable type-printer [name]...
97 disable type-printer [name]...
98 Enable or disable type printers.
100 set debug notification
101 show debug notification
102 Control display of debugging info for async remote notification.
106 ** For the Renesas Super-H architecture, the "regs" command has been removed
107 (has been deprecated in GDB 7.5), and "info all-registers" should be used
112 set print type methods (on|off)
113 show print type methods
114 Control whether method declarations are displayed by "ptype".
115 The default is to show them.
117 set print type typedefs (on|off)
118 show print type typedefs
119 Control whether typedef definitions are displayed by "ptype".
120 The default is to show them.
122 set filename-display basename|relative|absolute
123 show filename-display
124 Control the way in which filenames is displayed.
125 The default is "relative", which preserves previous behavior.
129 ** Command parameter changes are now notified using new async record
130 "=cmd-param-changed".
131 ** Trace frame changes caused by command "tfind" are now notified using
132 new async record "=traceframe-changed".
133 ** The creation and deletion of trace state variables are now notified
134 using new async records "=tsv-created" and "=tsv-deleted".
135 ** The start and stop of process record are now notified using new
136 async record "=record-started" and "=record-stopped".
137 ** Memory changes are now notified using new async record
139 ** The data-disassemble command response will include a "fullname" field
140 containing the absolute file name when GDB can determine it and source
142 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
143 command, to allow pattern filling of memory areas.
144 ** New commands "-catch-load"/"-catch-unload" added for intercepting
145 library load/unload events.
146 ** The response to breakpoint commands and breakpoint async records
147 includes an "installed" field containing a boolean state about each
148 non-pending tracepoint location is whether installed on target or not.
150 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
151 You must have the LZMA library available when configuring GDB for this
152 feature to be enabled. For more information, see:
153 http://fedoraproject.org/wiki/Features/MiniDebugInfo
155 *** Changes in GDB 7.5
157 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
158 for more x32 ABI info.
160 * GDB now supports access to MIPS DSP registers on Linux targets.
162 * GDB now supports debugging microMIPS binaries.
164 * The "info os" command on GNU/Linux can now display information on
165 several new classes of objects managed by the operating system:
166 "info os procgroups" lists process groups
167 "info os files" lists file descriptors
168 "info os sockets" lists internet-domain sockets
169 "info os shm" lists shared-memory regions
170 "info os semaphores" lists semaphores
171 "info os msg" lists message queues
172 "info os modules" lists loaded kernel modules
174 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
175 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
176 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
177 options and inspect the probe arguments using the new $_probe_arg family
178 of convenience variables. You can obtain more information about SystemTap
179 in <http://sourceware.org/systemtap/>.
181 * GDB now supports reversible debugging on ARM, it allows you to
182 debug basic ARM and THUMB instructions, and provides
183 record/replay support.
185 * The option "symbol-reloading" has been deleted as it is no longer used.
189 ** GDB commands implemented in Python can now be put in command class
192 ** The "maint set python print-stack on|off" is now deleted.
194 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
195 apply "flag enum"-style pretty-printing to any enum.
197 ** gdb.lookup_symbol can now work when there is no current frame.
199 ** gdb.Symbol now has a 'line' attribute, holding the line number in
200 the source at which the symbol was defined.
202 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
203 method 'value'. The former indicates whether the symbol needs a
204 frame in order to compute its value, and the latter computes the
207 ** A new method 'referenced_value' on gdb.Value objects which can
208 dereference pointer as well as C++ reference values.
210 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
211 which return the global and static blocks (as gdb.Block objects),
212 of the underlying symbol table, respectively.
214 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
215 object associated with a PC value.
217 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
218 of the address range occupied by code for the current source line.
220 * Go language support.
221 GDB now supports debugging programs written in the Go programming
224 * GDBserver now supports stdio connections.
225 E.g. (gdb) target remote | ssh myhost gdbserver - hello
227 * The binary "gdbtui" can no longer be built or installed.
228 Use "gdb -tui" instead.
230 * GDB will now print "flag" enums specially. A flag enum is one where
231 all the enumerator values have no bits in common when pairwise
232 "and"ed. When printing a value whose type is a flag enum, GDB will
233 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
234 (gdb) print (enum E) 3
237 * The filename part of a linespec will now match trailing components
238 of a source file name. For example, "break gcc/expr.c:1000" will
239 now set a breakpoint in build/gcc/expr.c, but not
242 * The "info proc" and "generate-core-file" commands will now also
243 work on remote targets connected to GDBserver on Linux.
245 * The command "info catch" has been removed. It has been disabled
248 * The "catch exception" and "catch assert" commands now accept
249 a condition at the end of the command, much like the "break"
250 command does. For instance:
252 (gdb) catch exception Constraint_Error if Barrier = True
254 Previously, it was possible to add a condition to such catchpoints,
255 but it had to be done as a second step, after the catchpoint had been
256 created, using the "condition" command.
258 * The "info static-tracepoint-marker" command will now also work on
259 native Linux targets with in-process agent.
261 * GDB can now set breakpoints on inlined functions.
263 * The .gdb_index section has been updated to include symbols for
264 inlined functions. GDB will ignore older .gdb_index sections by
265 default, which could cause symbol files to be loaded more slowly
266 until their .gdb_index sections can be recreated. The new command
267 "set use-deprecated-index-sections on" will cause GDB to use any older
268 .gdb_index sections it finds. This will restore performance, but the
269 ability to set breakpoints on inlined functions will be lost in symbol
270 files with older .gdb_index sections.
272 The .gdb_index section has also been updated to record more information
273 about each symbol. This speeds up the "info variables", "info functions"
274 and "info types" commands when used with programs having the .gdb_index
275 section, as well as speeding up debugging with shared libraries using
276 the .gdb_index section.
278 * Ada support for GDB/MI Variable Objects has been added.
280 * GDB can now support 'breakpoint always-inserted mode' in 'record'
285 ** New command -info-os is the MI equivalent of "info os".
287 ** Output logs ("set logging" and related) now include MI output.
291 ** "set use-deprecated-index-sections on|off"
292 "show use-deprecated-index-sections on|off"
293 Controls the use of deprecated .gdb_index sections.
295 ** "catch load" and "catch unload" can be used to stop when a shared
296 library is loaded or unloaded, respectively.
298 ** "enable count" can be used to auto-disable a breakpoint after
301 ** "info vtbl" can be used to show the virtual method tables for
302 C++ and Java objects.
304 ** "explore" and its sub commands "explore value" and "explore type"
305 can be used to reccursively explore values and types of
306 expressions. These commands are available only if GDB is
307 configured with '--with-python'.
309 ** "info auto-load" shows status of all kinds of auto-loaded files,
310 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
311 sequences of commands files, "info auto-load python-scripts"
312 shows status of auto-loading Python script files,
313 "info auto-load local-gdbinit" shows status of loading init file
314 (.gdbinit) from current directory and "info auto-load libthread-db" shows
315 status of inferior specific thread debugging shared library loading.
317 ** "info auto-load-scripts", "set auto-load-scripts on|off"
318 and "show auto-load-scripts" commands have been deprecated, use their
319 "info auto-load python-scripts", "set auto-load python-scripts on|off"
320 and "show auto-load python-scripts" counterparts instead.
322 ** "dprintf location,format,args..." creates a dynamic printf, which
323 is basically a breakpoint that does a printf and immediately
324 resumes your program's execution, so it is like a printf that you
325 can insert dynamically at runtime instead of at compiletime.
327 ** "set print symbol"
329 Controls whether GDB attempts to display the symbol, if any,
330 corresponding to addresses it prints. This defaults to "on", but
331 you can set it to "off" to restore GDB's previous behavior.
333 * Deprecated commands
335 ** For the Renesas Super-H architecture, the "regs" command has been
336 deprecated, and "info all-registers" should be used instead.
340 Renesas RL78 rl78-*-elf
341 HP OpenVMS ia64 ia64-hp-openvms*
343 * GDBserver supports evaluation of breakpoint conditions. When
344 support is advertised by GDBserver, GDB may be told to send the
345 breakpoint conditions in bytecode form to GDBserver. GDBserver
346 will only report the breakpoint trigger to GDB when its condition
352 show mips compression
353 Select the compressed ISA encoding used in functions that have no symbol
354 information available. The encoding can be set to either of:
357 and is updated automatically from ELF file flags if available.
359 set breakpoint condition-evaluation
360 show breakpoint condition-evaluation
361 Control whether breakpoint conditions are evaluated by GDB ("host") or by
362 GDBserver ("target"). Default option "auto" chooses the most efficient
364 This option can improve debugger efficiency depending on the speed of the
368 Disable auto-loading globally.
371 Show auto-loading setting of all kinds of auto-loaded files.
373 set auto-load gdb-scripts on|off
374 show auto-load gdb-scripts
375 Control auto-loading of GDB canned sequences of commands files.
377 set auto-load python-scripts on|off
378 show auto-load python-scripts
379 Control auto-loading of Python script files.
381 set auto-load local-gdbinit on|off
382 show auto-load local-gdbinit
383 Control loading of init file (.gdbinit) from current directory.
385 set auto-load libthread-db on|off
386 show auto-load libthread-db
387 Control auto-loading of inferior specific thread debugging shared library.
389 set auto-load scripts-directory <dir1>[:<dir2>...]
390 show auto-load scripts-directory
391 Set a list of directories from which to load auto-loaded scripts.
392 Automatically loaded Python scripts and GDB scripts are located in one
393 of the directories listed by this option.
394 The delimiter (':' above) may differ according to the host platform.
396 set auto-load safe-path <dir1>[:<dir2>...]
397 show auto-load safe-path
398 Set a list of directories from which it is safe to auto-load files.
399 The delimiter (':' above) may differ according to the host platform.
401 set debug auto-load on|off
403 Control display of debugging info for auto-loading the files above.
405 set dprintf-style gdb|call|agent
407 Control the way in which a dynamic printf is performed; "gdb"
408 requests a GDB printf command, while "call" causes dprintf to call a
409 function in the inferior. "agent" requests that the target agent
410 (such as GDBserver) do the printing.
412 set dprintf-function <expr>
413 show dprintf-function
414 set dprintf-channel <expr>
416 Set the function and optional first argument to the call when using
417 the "call" style of dynamic printf.
419 set disconnected-dprintf on|off
420 show disconnected-dprintf
421 Control whether agent-style dynamic printfs continue to be in effect
422 after GDB disconnects.
424 * New configure options
427 Configure default value for the 'set auto-load scripts-directory'
428 setting above. It defaults to '$debugdir:$datadir/auto-load',
429 $debugdir representing global debugging info directories (available
430 via 'show debug-file-directory') and $datadir representing GDB's data
431 directory (available via 'show data-directory').
433 --with-auto-load-safe-path
434 Configure default value for the 'set auto-load safe-path' setting
435 above. It defaults to the --with-auto-load-dir setting.
437 --without-auto-load-safe-path
438 Set 'set auto-load safe-path' to '/', effectively disabling this
443 z0/z1 conditional breakpoints extension
445 The z0/z1 breakpoint insertion packets have been extended to carry
446 a list of conditional expressions over to the remote stub depending on the
447 condition evaluation mode. The use of this extension can be controlled
448 via the "set remote conditional-breakpoints-packet" command.
452 Specify the signals which the remote stub may pass to the debugged
453 program without GDB involvement.
455 * New command line options
457 --init-command=FILE, -ix Like --command, -x but execute it
458 before loading inferior.
459 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
460 execute it before loading inferior.
462 *** Changes in GDB 7.4
464 * GDB now handles ambiguous linespecs more consistently; the existing
465 FILE:LINE support has been expanded to other types of linespecs. A
466 breakpoint will now be set on all matching locations in all
467 inferiors, and locations will be added or removed according to
470 * GDB now allows you to skip uninteresting functions and files when
471 stepping with the "skip function" and "skip file" commands.
473 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
474 and "show remote hardware-watchpoint-length-limit". These allows to
475 set or show the maximum length limit (in bytes) of a remote
476 target hardware watchpoint.
478 This allows e.g. to use "unlimited" hardware watchpoints with the
479 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
480 watchpoints are slower than real hardware watchpoints but are
481 significantly faster than gdb software watchpoints.
485 ** The register_pretty_printer function in module gdb.printing now takes
486 an optional `replace' argument. If True, the new printer replaces any
489 ** The "maint set python print-stack on|off" command has been
490 deprecated and will be deleted in GDB 7.5.
491 A new command: "set python print-stack none|full|message" has
492 replaced it. Additionally, the default for "print-stack" is
493 now "message", which just prints the error message without
496 ** A prompt substitution hook (prompt_hook) is now available to the
499 ** A new Python module, gdb.prompt has been added to the GDB Python
500 modules library. This module provides functionality for
501 escape sequences in prompts (used by set/show
502 extended-prompt). These escape sequences are replaced by their
505 ** Python commands and convenience-functions located in
506 'data-directory'/python/gdb/command and
507 'data-directory'/python/gdb/function are now automatically loaded
510 ** Blocks now provide four new attributes. global_block and
511 static_block will return the global and static blocks
512 respectively. is_static and is_global are boolean attributes
513 that indicate if the block is one of those two types.
515 ** Symbols now provide the "type" attribute, the type of the symbol.
517 ** The "gdb.breakpoint" function has been deprecated in favor of
520 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
521 of a function. This class is based on the "finish" command
522 available in the CLI.
524 ** Type objects for struct and union types now allow access to
525 the fields using standard Python dictionary (mapping) methods.
526 For example, "some_type['myfield']" now works, as does
529 ** A new event "gdb.new_objfile" has been added, triggered by loading a
532 ** A new function, "deep_items" has been added to the gdb.types
533 module in the GDB Python modules library. This function returns
534 an iterator over the fields of a struct or union type. Unlike
535 the standard Python "iteritems" method, it will recursively traverse
536 any anonymous fields.
540 ** "*stopped" events can report several new "reason"s, such as
543 ** Breakpoint changes are now notified using new async records, like
544 "=breakpoint-modified".
546 ** New command -ada-task-info.
548 * libthread-db-search-path now supports two special values: $sdir and $pdir.
549 $sdir specifies the default system locations of shared libraries.
550 $pdir specifies the directory where the libpthread used by the application
553 GDB no longer looks in $sdir and $pdir after it has searched the directories
554 mentioned in libthread-db-search-path. If you want to search those
555 directories, they must be specified in libthread-db-search-path.
556 The default value of libthread-db-search-path on GNU/Linux and Solaris
557 systems is now "$sdir:$pdir".
559 $pdir is not supported by gdbserver, it is currently ignored.
560 $sdir is supported by gdbserver.
562 * New configure option --with-iconv-bin.
563 When using the internationalization support like the one in the GNU C
564 library, GDB will invoke the "iconv" program to get a list of supported
565 character sets. If this program lives in a non-standard location, one can
566 use this option to specify where to find it.
568 * When natively debugging programs on PowerPC BookE processors running
569 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
570 watchpoints, which specify a mask in addition to an address to watch.
571 The mask specifies that some bits of an address (the bits which are
572 reset in the mask) should be ignored when matching the address accessed
573 by the inferior against the watchpoint address. See the "PowerPC Embedded"
574 section in the user manual for more details.
576 * The new option --once causes GDBserver to stop listening for connections once
577 the first connection is made. The listening port used by GDBserver will
578 become available after that.
580 * New commands "info macros" and "alias" have been added.
582 * New function parameters suffix @entry specifies value of function parameter
583 at the time the function got called. Entry values are available only since
589 "!" is now an alias of the "shell" command.
590 Note that no space is needed between "!" and SHELL COMMAND.
594 watch EXPRESSION mask MASK_VALUE
595 The watch command now supports the mask argument which allows creation
596 of masked watchpoints, if the current architecture supports this feature.
598 info auto-load-scripts [REGEXP]
599 This command was formerly named "maintenance print section-scripts".
600 It is now generally useful and is no longer a maintenance-only command.
602 info macro [-all] [--] MACRO
603 The info macro command has new options `-all' and `--'. The first for
604 printing all definitions of a macro. The second for explicitly specifying
605 the end of arguments and the beginning of the macro name in case the macro
606 name starts with a hyphen.
608 collect[/s] EXPRESSIONS
609 The tracepoint collect command now takes an optional modifier "/s"
610 that directs it to dereference pointer-to-character types and
611 collect the bytes of memory up to a zero byte. The behavior is
612 similar to what you see when you use the regular print command on a
613 string. An optional integer following the "/s" sets a bound on the
614 number of bytes that will be collected.
617 The trace start command now interprets any supplied arguments as a
618 note to be recorded with the trace run, with an effect similar to
619 setting the variable trace-notes.
622 The trace stop command now interprets any arguments as a note to be
623 mentioned along with the tstatus report that the trace was stopped
624 with a command. The effect is similar to setting the variable
627 * Tracepoints can now be enabled and disabled at any time after a trace
628 experiment has been started using the standard "enable" and "disable"
629 commands. It is now possible to start a trace experiment with no enabled
630 tracepoints; GDB will display a warning, but will allow the experiment to
631 begin, assuming that tracepoints will be enabled as needed while the trace
634 * Fast tracepoints on 32-bit x86-architectures can now be placed at
635 locations with 4-byte instructions, when they were previously
636 limited to locations with instructions of 5 bytes or longer.
640 set debug dwarf2-read
641 show debug dwarf2-read
642 Turns on or off display of debugging messages related to reading
643 DWARF debug info. The default is off.
645 set debug symtab-create
646 show debug symtab-create
647 Turns on or off display of debugging messages related to symbol table
648 creation. The default is off.
652 Set the GDB prompt, and allow escape sequences to be inserted to
653 display miscellaneous information (see 'help set extended-prompt'
654 for the list of sequences). This prompt (and any information
655 accessed through the escape sequences) is updated every time the
658 set print entry-values (both|compact|default|if-needed|no|only|preferred)
659 show print entry-values
660 Set printing of frame argument values at function entry. In some cases
661 GDB can determine the value of function argument which was passed by the
662 function caller, even if the value was modified inside the called function.
664 set debug entry-values
665 show debug entry-values
666 Control display of debugging info for determining frame argument values at
667 function entry and virtual tail call frames.
669 set basenames-may-differ
670 show basenames-may-differ
671 Set whether a source file may have multiple base names.
672 (A "base name" is the name of a file with the directory part removed.
673 Example: The base name of "/home/user/hello.c" is "hello.c".)
674 If set, GDB will canonicalize file names (e.g., expand symlinks)
675 before comparing them. Canonicalization is an expensive operation,
676 but it allows the same file be known by more than one base name.
677 If not set (the default), all source files are assumed to have just
678 one base name, and gdb will do file name comparisons more efficiently.
684 Set a user name and notes for the current and any future trace runs.
685 This is useful for long-running and/or disconnected traces, to
686 inform others (or yourself) as to who is running the trace, supply
687 contact information, or otherwise explain what is going on.
690 show trace-stop-notes
691 Set a note attached to the trace run, that is displayed when the
692 trace has been stopped by a tstop command. This is useful for
693 instance as an explanation, if you are stopping a trace run that was
694 started by someone else.
700 Dynamically enable a tracepoint in a started trace experiment.
704 Dynamically disable a tracepoint in a started trace experiment.
708 Set the user and notes of the trace run.
712 Query the current status of a tracepoint.
716 Query the minimum length of instruction at which a fast tracepoint may
719 * Dcache size (number of lines) and line-size are now runtime-configurable
720 via "set dcache line" and "set dcache line-size" commands.
724 Texas Instruments TMS320C6x tic6x-*-*
728 Renesas RL78 rl78-*-elf
730 *** Changes in GDB 7.3.1
732 * The build failure for NetBSD and OpenBSD targets have now been fixed.
734 *** Changes in GDB 7.3
736 * GDB has a new command: "thread find [REGEXP]".
737 It finds the thread id whose name, target id, or thread extra info
738 matches the given regular expression.
740 * The "catch syscall" command now works on mips*-linux* targets.
742 * The -data-disassemble MI command now supports modes 2 and 3 for
743 dumping the instruction opcodes.
745 * New command line options
747 -data-directory DIR Specify DIR as the "data-directory".
748 This is mostly for testing purposes.
750 * The "maint set python auto-load on|off" command has been renamed to
751 "set auto-load-scripts on|off".
753 * GDB has a new command: "set directories".
754 It is like the "dir" command except that it replaces the
755 source path list instead of augmenting it.
757 * GDB now understands thread names.
759 On GNU/Linux, "info threads" will display the thread name as set by
760 prctl or pthread_setname_np.
762 There is also a new command, "thread name", which can be used to
763 assign a name internally for GDB to display.
766 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
767 has been integrated into GDB.
771 ** The function gdb.Write now accepts an optional keyword 'stream'.
772 This keyword, when provided, will direct the output to either
773 stdout, stderr, or GDB's logging output.
775 ** Parameters can now be be sub-classed in Python, and in particular
776 you may implement the get_set_doc and get_show_doc functions.
777 This improves how Parameter set/show documentation is processed
778 and allows for more dynamic content.
780 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
781 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
782 have an is_valid method.
784 ** Breakpoints can now be sub-classed in Python, and in particular
785 you may implement a 'stop' function that is executed each time
786 the inferior reaches that breakpoint.
788 ** New function gdb.lookup_global_symbol looks up a global symbol.
790 ** GDB values in Python are now callable if the value represents a
791 function. For example, if 'some_value' represents a function that
792 takes two integer parameters and returns a value, you can call
793 that function like so:
795 result = some_value (10,20)
797 ** Module gdb.types has been added.
798 It contains a collection of utilities for working with gdb.Types objects:
799 get_basic_type, has_field, make_enum_dict.
801 ** Module gdb.printing has been added.
802 It contains utilities for writing and registering pretty-printers.
803 New classes: PrettyPrinter, SubPrettyPrinter,
804 RegexpCollectionPrettyPrinter.
805 New function: register_pretty_printer.
807 ** New commands "info pretty-printers", "enable pretty-printer" and
808 "disable pretty-printer" have been added.
810 ** gdb.parameter("directories") is now available.
812 ** New function gdb.newest_frame returns the newest frame in the
815 ** The gdb.InferiorThread class has a new "name" attribute. This
816 holds the thread's name.
818 ** Python Support for Inferior events.
819 Python scripts can add observers to be notified of events
820 occurring in the process being debugged.
821 The following events are currently supported:
822 - gdb.events.cont Continue event.
823 - gdb.events.exited Inferior exited event.
824 - gdb.events.stop Signal received, and Breakpoint hit events.
828 ** GDB now puts template parameters in scope when debugging in an
829 instantiation. For example, if you have:
831 template<int X> int func (void) { return X; }
833 then if you step into func<5>, "print X" will show "5". This
834 feature requires proper debuginfo support from the compiler; it
835 was added to GCC 4.5.
837 ** The motion commands "next", "finish", "until", and "advance" now
838 work better when exceptions are thrown. In particular, GDB will
839 no longer lose control of the inferior; instead, the GDB will
840 stop the inferior at the point at which the exception is caught.
841 This functionality requires a change in the exception handling
842 code that was introduced in GCC 4.5.
844 * GDB now follows GCC's rules on accessing volatile objects when
845 reading or writing target state during expression evaluation.
846 One notable difference to prior behavior is that "print x = 0"
847 no longer generates a read of x; the value of the assignment is
848 now always taken directly from the value being assigned.
850 * GDB now has some support for using labels in the program's source in
851 linespecs. For instance, you can use "advance label" to continue
852 execution to a label.
854 * GDB now has support for reading and writing a new .gdb_index
855 section. This section holds a fast index of DWARF debugging
856 information and can be used to greatly speed up GDB startup and
857 operation. See the documentation for `save gdb-index' for details.
859 * The "watch" command now accepts an optional "-location" argument.
860 When used, this causes GDB to watch the memory referred to by the
861 expression. Such a watchpoint is never deleted due to it going out
864 * GDB now supports thread debugging of core dumps on GNU/Linux.
866 GDB now activates thread debugging using the libthread_db library
867 when debugging GNU/Linux core dumps, similarly to when debugging
868 live processes. As a result, when debugging a core dump file, GDB
869 is now able to display pthread_t ids of threads. For example, "info
870 threads" shows the same output as when debugging the process when it
871 was live. In earlier releases, you'd see something like this:
874 * 1 LWP 6780 main () at main.c:10
876 While now you see this:
879 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
881 It is also now possible to inspect TLS variables when debugging core
884 When debugging a core dump generated on a machine other than the one
885 used to run GDB, you may need to point GDB at the correct
886 libthread_db library with the "set libthread-db-search-path"
887 command. See the user manual for more details on this command.
889 * When natively debugging programs on PowerPC BookE processors running
890 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
891 which stop execution of the inferior whenever it executes an instruction
892 at any address within the specified range. See the "PowerPC Embedded"
893 section in the user manual for more details.
895 * New features in the GDB remote stub, GDBserver
897 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
898 and i686 LynxOS (version 5.x).
900 ** GDBserver is now supported on Blackfin Linux.
902 * New native configurations
904 ia64 HP-UX ia64-*-hpux*
908 Analog Devices, Inc. Blackfin Processor bfin-*
910 * Ada task switching is now supported on sparc-elf targets when
911 debugging a program using the Ravenscar Profile. For more information,
912 see the "Tasking Support when using the Ravenscar Profile" section
913 in the GDB user manual.
915 * Guile support was removed.
917 * New features in the GNU simulator
919 ** The --map-info flag lists all known core mappings.
921 ** CFI flashes may be simulated via the "cfi" device.
923 *** Changes in GDB 7.2
925 * Shared library support for remote targets by default
927 When GDB is configured for a generic, non-OS specific target, like
928 for example, --target=arm-eabi or one of the many *-*-elf targets,
929 GDB now queries remote stubs for loaded shared libraries using the
930 `qXfer:libraries:read' packet. Previously, shared library support
931 was always disabled for such configurations.
935 ** Argument Dependent Lookup (ADL)
937 In C++ ADL lookup directs function search to the namespaces of its
938 arguments even if the namespace has not been imported.
948 Here the compiler will search for `foo' in the namespace of 'b'
949 and find A::foo. GDB now supports this. This construct is commonly
950 used in the Standard Template Library for operators.
952 ** Improved User Defined Operator Support
954 In addition to member operators, GDB now supports lookup of operators
955 defined in a namespace and imported with a `using' directive, operators
956 defined in the global scope, operators imported implicitly from an
957 anonymous namespace, and the ADL operators mentioned in the previous
959 GDB now also supports proper overload resolution for all the previously
960 mentioned flavors of operators.
962 ** static const class members
964 Printing of static const class members that are initialized in the
965 class definition has been fixed.
967 * Windows Thread Information Block access.
969 On Windows targets, GDB now supports displaying the Windows Thread
970 Information Block (TIB) structure. This structure is visible either
971 by using the new command `info w32 thread-information-block' or, by
972 dereferencing the new convenience variable named `$_tlb', a
973 thread-specific pointer to the TIB. This feature is also supported
974 when remote debugging using GDBserver.
978 Static tracepoints are calls in the user program into a tracing
979 library. One such library is a port of the LTTng kernel tracer to
980 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
981 When debugging with GDBserver, GDB now supports combining the GDB
982 tracepoint machinery with such libraries. For example: the user can
983 use GDB to probe a static tracepoint marker (a call from the user
984 program into the tracing library) with the new "strace" command (see
985 "New commands" below). This creates a "static tracepoint" in the
986 breakpoint list, that can be manipulated with the same feature set
987 as fast and regular tracepoints. E.g., collect registers, local and
988 global variables, collect trace state variables, and define
989 tracepoint conditions. In addition, the user can collect extra
990 static tracepoint marker specific data, by collecting the new
991 $_sdata internal variable. When analyzing the trace buffer, you can
992 inspect $_sdata like any other variable available to GDB. For more
993 information, see the "Tracepoints" chapter in GDB user manual. New
994 remote packets have been defined to support static tracepoints, see
995 the "New remote packets" section below.
997 * Better reconstruction of tracepoints after disconnected tracing
999 GDB will attempt to download the original source form of tracepoint
1000 definitions when starting a trace run, and then will upload these
1001 upon reconnection to the target, resulting in a more accurate
1002 reconstruction of the tracepoints that are in use on the target.
1006 You can now exercise direct control over the ways that GDB can
1007 affect your program. For instance, you can disallow the setting of
1008 breakpoints, so that the program can run continuously (assuming
1009 non-stop mode). In addition, the "observer" variable is available
1010 to switch all of the different controls; in observer mode, GDB
1011 cannot affect the target's behavior at all, which is useful for
1012 tasks like diagnosing live systems in the field.
1014 * The new convenience variable $_thread holds the number of the
1017 * New remote packets
1021 Return the address of the Windows Thread Information Block of a given thread.
1025 In response to several of the tracepoint packets, the target may now
1026 also respond with a number of intermediate `qRelocInsn' request
1027 packets before the final result packet, to have GDB handle
1028 relocating an instruction to execute at a different address. This
1029 is particularly useful for stubs that support fast tracepoints. GDB
1030 reports support for this feature in the qSupported packet.
1034 List static tracepoint markers in the target program.
1038 List static tracepoint markers at a given address in the target
1041 qXfer:statictrace:read
1043 Read the static trace data collected (by a `collect $_sdata'
1044 tracepoint action). The remote stub reports support for this packet
1045 to gdb's qSupported query.
1049 Send the current settings of GDB's permission flags.
1053 Send part of the source (textual) form of a tracepoint definition,
1054 which includes location, conditional, and action list.
1056 * The source command now accepts a -s option to force searching for the
1057 script in the source search path even if the script name specifies
1060 * New features in the GDB remote stub, GDBserver
1062 - GDBserver now support tracepoints (including fast tracepoints, and
1063 static tracepoints). The feature is currently supported by the
1064 i386-linux and amd64-linux builds. See the "Tracepoints support
1065 in gdbserver" section in the manual for more information.
1067 GDBserver JIT compiles the tracepoint's conditional agent
1068 expression bytecode into native code whenever possible for low
1069 overhead dynamic tracepoints conditionals. For such tracepoints,
1070 an expression that examines program state is evaluated when the
1071 tracepoint is reached, in order to determine whether to capture
1072 trace data. If the condition is simple and false, processing the
1073 tracepoint finishes very quickly and no data is gathered.
1075 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1076 for static tracepoints support.
1078 - GDBserver now supports x86_64 Windows 64-bit debugging.
1080 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1081 it understands register description.
1083 * The --batch flag now disables pagination and queries.
1085 * X86 general purpose registers
1087 GDB now supports reading/writing byte, word and double-word x86
1088 general purpose registers directly. This means you can use, say,
1089 $ah or $ax to refer, respectively, to the byte register AH and
1090 16-bit word register AX that are actually portions of the 32-bit
1091 register EAX or 64-bit register RAX.
1093 * The `commands' command now accepts a range of breakpoints to modify.
1094 A plain `commands' following a command that creates multiple
1095 breakpoints affects all the breakpoints set by that command. This
1096 applies to breakpoints set by `rbreak', and also applies when a
1097 single `break' command creates multiple breakpoints (e.g.,
1098 breakpoints on overloaded c++ functions).
1100 * The `rbreak' command now accepts a filename specification as part of
1101 its argument, limiting the functions selected by the regex to those
1102 in the specified file.
1104 * Support for remote debugging Windows and SymbianOS shared libraries
1105 from Unix hosts has been improved. Non Windows GDB builds now can
1106 understand target reported file names that follow MS-DOS based file
1107 system semantics, such as file names that include drive letters and
1108 use the backslash character as directory separator. This makes it
1109 possible to transparently use the "set sysroot" and "set
1110 solib-search-path" on Unix hosts to point as host copies of the
1111 target's shared libraries. See the new command "set
1112 target-file-system-kind" described below, and the "Commands to
1113 specify files" section in the user manual for more information.
1117 eval template, expressions...
1118 Convert the values of one or more expressions under the control
1119 of the string template to a command line, and call it.
1121 set target-file-system-kind unix|dos-based|auto
1122 show target-file-system-kind
1123 Set or show the assumed file system kind for target reported file
1126 save breakpoints <filename>
1127 Save all current breakpoint definitions to a file suitable for use
1128 in a later debugging session. To read the saved breakpoint
1129 definitions, use the `source' command.
1131 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1134 info static-tracepoint-markers
1135 Display information about static tracepoint markers in the target.
1137 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1138 Define a static tracepoint by probing a marker at the given
1139 function, line, address, or marker ID.
1143 Enable and disable observer mode.
1145 set may-write-registers on|off
1146 set may-write-memory on|off
1147 set may-insert-breakpoints on|off
1148 set may-insert-tracepoints on|off
1149 set may-insert-fast-tracepoints on|off
1150 set may-interrupt on|off
1151 Set individual permissions for GDB effects on the target. Note that
1152 some of these settings can have undesirable or surprising
1153 consequences, particularly when changed in the middle of a session.
1154 For instance, disabling the writing of memory can prevent
1155 breakpoints from being inserted, cause single-stepping to fail, or
1156 even crash your program, if you disable after breakpoints have been
1157 inserted. However, GDB should not crash.
1159 set record memory-query on|off
1160 show record memory-query
1161 Control whether to stop the inferior if memory changes caused
1162 by an instruction cannot be recorded.
1167 The disassemble command now supports "start,+length" form of two arguments.
1171 ** GDB now provides a new directory location, called the python directory,
1172 where Python scripts written for GDB can be installed. The location
1173 of that directory is <data-directory>/python, where <data-directory>
1174 is the GDB data directory. For more details, see section `Scripting
1175 GDB using Python' in the manual.
1177 ** The GDB Python API now has access to breakpoints, symbols, symbol
1178 tables, program spaces, inferiors, threads and frame's code blocks.
1179 Additionally, GDB Parameters can now be created from the API, and
1180 manipulated via set/show in the CLI.
1182 ** New functions gdb.target_charset, gdb.target_wide_charset,
1183 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1185 ** New exception gdb.GdbError.
1187 ** Pretty-printers are now also looked up in the current program space.
1189 ** Pretty-printers can now be individually enabled and disabled.
1191 ** GDB now looks for names of Python scripts to auto-load in a
1192 special section named `.debug_gdb_scripts', in addition to looking
1193 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1195 * Tracepoint actions were unified with breakpoint commands. In particular,
1196 there are no longer differences in "info break" output for breakpoints and
1197 tracepoints and the "commands" command can be used for both tracepoints and
1198 regular breakpoints.
1202 ARM Symbian arm*-*-symbianelf*
1204 * D language support.
1205 GDB now supports debugging programs written in the D programming
1208 * GDB now supports the extended ptrace interface for PowerPC which is
1209 available since Linux kernel version 2.6.34. This automatically enables
1210 any hardware breakpoints and additional hardware watchpoints available in
1211 the processor. The old ptrace interface exposes just one hardware
1212 watchpoint and no hardware breakpoints.
1214 * GDB is now able to use the Data Value Compare (DVC) register available on
1215 embedded PowerPC processors to implement in hardware simple watchpoint
1216 conditions of the form:
1218 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1220 This works in native GDB running on Linux kernels with the extended ptrace
1221 interface mentioned above.
1223 *** Changes in GDB 7.1
1227 ** Namespace Support
1229 GDB now supports importing of namespaces in C++. This enables the
1230 user to inspect variables from imported namespaces. Support for
1231 namepace aliasing has also been added. So, if a namespace is
1232 aliased in the current scope (e.g. namepace C=A; ) the user can
1233 print variables using the alias (e.g. (gdb) print C::x).
1237 All known bugs relating to the printing of virtual base class were
1238 fixed. It is now possible to call overloaded static methods using a
1243 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1244 and reinterpret_cast<> are now handled by the C++ expression parser.
1248 Xilinx MicroBlaze microblaze-*-*
1253 Xilinx MicroBlaze microblaze
1256 * Multi-program debugging.
1258 GDB now has support for multi-program (a.k.a. multi-executable or
1259 multi-exec) debugging. This allows for debugging multiple inferiors
1260 simultaneously each running a different program under the same GDB
1261 session. See "Debugging Multiple Inferiors and Programs" in the
1262 manual for more information. This implied some user visible changes
1263 in the multi-inferior support. For example, "info inferiors" now
1264 lists inferiors that are not running yet or that have exited
1265 already. See also "New commands" and "New options" below.
1267 * New tracing features
1269 GDB's tracepoint facility now includes several new features:
1271 ** Trace state variables
1273 GDB tracepoints now include support for trace state variables, which
1274 are variables managed by the target agent during a tracing
1275 experiment. They are useful for tracepoints that trigger each
1276 other, so for instance one tracepoint can count hits in a variable,
1277 and then a second tracepoint has a condition that is true when the
1278 count reaches a particular value. Trace state variables share the
1279 $-syntax of GDB convenience variables, and can appear in both
1280 tracepoint actions and condition expressions. Use the "tvariable"
1281 command to create, and "info tvariables" to view; see "Trace State
1282 Variables" in the manual for more detail.
1286 GDB now includes an option for defining fast tracepoints, which
1287 targets may implement more efficiently, such as by installing a jump
1288 into the target agent rather than a trap instruction. The resulting
1289 speedup can be by two orders of magnitude or more, although the
1290 tradeoff is that some program locations on some target architectures
1291 might not allow fast tracepoint installation, for instance if the
1292 instruction to be replaced is shorter than the jump. To request a
1293 fast tracepoint, use the "ftrace" command, with syntax identical to
1294 the regular trace command.
1296 ** Disconnected tracing
1298 It is now possible to detach GDB from the target while it is running
1299 a trace experiment, then reconnect later to see how the experiment
1300 is going. In addition, a new variable disconnected-tracing lets you
1301 tell the target agent whether to continue running a trace if the
1302 connection is lost unexpectedly.
1306 GDB now has the ability to save the trace buffer into a file, and
1307 then use that file as a target, similarly to you can do with
1308 corefiles. You can select trace frames, print data that was
1309 collected in them, and use tstatus to display the state of the
1310 tracing run at the moment that it was saved. To create a trace
1311 file, use "tsave <filename>", and to use it, do "target tfile
1314 ** Circular trace buffer
1316 You can ask the target agent to handle the trace buffer as a
1317 circular buffer, discarding the oldest trace frames to make room for
1318 newer ones, by setting circular-trace-buffer to on. This feature may
1319 not be available for all target agents.
1324 The disassemble command, when invoked with two arguments, now requires
1325 the arguments to be comma-separated.
1328 The info variables command now displays variable definitions. Files
1329 which only declare a variable are not shown.
1332 The source command is now capable of sourcing Python scripts.
1333 This feature is dependent on the debugger being build with Python
1336 Related to this enhancement is also the introduction of a new command
1337 "set script-extension" (see below).
1339 * New commands (for set/show, see "New options" below)
1341 record save [<FILENAME>]
1342 Save a file (in core file format) containing the process record
1343 execution log for replay debugging at a later time.
1345 record restore <FILENAME>
1346 Restore the process record execution log that was saved at an
1347 earlier time, for replay debugging.
1349 add-inferior [-copies <N>] [-exec <FILENAME>]
1352 clone-inferior [-copies <N>] [ID]
1353 Make a new inferior ready to execute the same program another
1354 inferior has loaded.
1359 maint info program-spaces
1360 List the program spaces loaded into GDB.
1362 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1363 show remote interrupt-sequence
1364 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1365 as the sequence to the remote target in order to interrupt the execution.
1366 Ctrl-C is a default. Some system prefers BREAK which is high level of
1367 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1368 Magic SysRq g. It is BREAK signal and character 'g'.
1370 set remote interrupt-on-connect [on | off]
1371 show remote interrupt-on-connect
1372 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1373 remote target when gdb connects to it. This is needed when you debug
1376 set remotebreak [on | off]
1378 Deprecated. Use "set/show remote interrupt-sequence" instead.
1380 tvariable $NAME [ = EXP ]
1381 Create or modify a trace state variable.
1384 List trace state variables and their values.
1386 delete tvariable $NAME ...
1387 Delete one or more trace state variables.
1390 Evaluate the given expressions without collecting anything into the
1391 trace buffer. (Valid in tracepoint actions only.)
1393 ftrace FN / FILE:LINE / *ADDR
1394 Define a fast tracepoint at the given function, line, or address.
1396 * New expression syntax
1398 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1399 GDB now parses 0b101010 identically with 42.
1403 set follow-exec-mode new|same
1404 show follow-exec-mode
1405 Control whether GDB reuses the same inferior across an exec call or
1406 creates a new one. This is useful to be able to restart the old
1407 executable after the inferior having done an exec call.
1409 set default-collect EXPR, ...
1410 show default-collect
1411 Define a list of expressions to be collected at each tracepoint.
1412 This is a useful way to ensure essential items are not overlooked,
1413 such as registers or a critical global variable.
1415 set disconnected-tracing
1416 show disconnected-tracing
1417 If set to 1, the target is instructed to continue tracing if it
1418 loses its connection to GDB. If 0, the target is to stop tracing
1421 set circular-trace-buffer
1422 show circular-trace-buffer
1423 If set to on, the target is instructed to use a circular trace buffer
1424 and discard the oldest trace frames instead of stopping the trace due
1425 to a full trace buffer. If set to off, the trace stops when the buffer
1426 fills up. Some targets may not support this.
1428 set script-extension off|soft|strict
1429 show script-extension
1430 If set to "off", the debugger does not perform any script language
1431 recognition, and all sourced files are assumed to be GDB scripts.
1432 If set to "soft" (the default), files are sourced according to
1433 filename extension, falling back to GDB scripts if the first
1435 If set to "strict", files are sourced according to filename extension.
1437 set ada trust-PAD-over-XVS on|off
1438 show ada trust-PAD-over-XVS
1439 If off, activate a workaround against a bug in the debugging information
1440 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1441 the GCC sources for more information about the GNAT encoding and
1442 PAD types in particular). It is always safe to set this option to
1443 off, but this introduces a slight performance penalty. The default
1446 * Python API Improvements
1448 ** GDB provides the new class gdb.LazyString. This is useful in
1449 some pretty-printing cases. The new method gdb.Value.lazy_string
1450 provides a simple way to create objects of this type.
1452 ** The fields returned by gdb.Type.fields now have an
1453 `is_base_class' attribute.
1455 ** The new method gdb.Type.range returns the range of an array type.
1457 ** The new method gdb.parse_and_eval can be used to parse and
1458 evaluate an expression.
1460 * New remote packets
1463 Define a trace state variable.
1466 Get the current value of a trace state variable.
1469 Set desired tracing behavior upon disconnection.
1472 Set the trace buffer to be linear or circular.
1475 Get data about the tracepoints currently in use.
1479 Process record now works correctly with hardware watchpoints.
1481 Multiple bug fixes have been made to the mips-irix port, making it
1482 much more reliable. In particular:
1483 - Debugging threaded applications is now possible again. Previously,
1484 GDB would hang while starting the program, or while waiting for
1485 the program to stop at a breakpoint.
1486 - Attaching to a running process no longer hangs.
1487 - An error occurring while loading a core file has been fixed.
1488 - Changing the value of the PC register now works again. This fixes
1489 problems observed when using the "jump" command, or when calling
1490 a function from GDB, or even when assigning a new value to $pc.
1491 - With the "finish" and "return" commands, the return value for functions
1492 returning a small array is now correctly printed.
1493 - It is now possible to break on shared library code which gets executed
1494 during a shared library init phase (code executed while executing
1495 their .init section). Previously, the breakpoint would have no effect.
1496 - GDB is now able to backtrace through the signal handler for
1497 non-threaded programs.
1499 PIE (Position Independent Executable) programs debugging is now supported.
1500 This includes debugging execution of PIC (Position Independent Code) shared
1501 libraries although for that, it should be possible to run such libraries as an
1504 *** Changes in GDB 7.0
1506 * GDB now has an interface for JIT compilation. Applications that
1507 dynamically generate code can create symbol files in memory and register
1508 them with GDB. For users, the feature should work transparently, and
1509 for JIT developers, the interface is documented in the GDB manual in the
1510 "JIT Compilation Interface" chapter.
1512 * Tracepoints may now be conditional. The syntax is as for
1513 breakpoints; either an "if" clause appended to the "trace" command,
1514 or the "condition" command is available. GDB sends the condition to
1515 the target for evaluation using the same bytecode format as is used
1516 for tracepoint actions.
1518 * The disassemble command now supports: an optional /r modifier, print the
1519 raw instructions in hex as well as in symbolic form, and an optional /m
1520 modifier to print mixed source+assembly.
1522 * Process record and replay
1524 In a architecture environment that supports ``process record and
1525 replay'', ``process record and replay'' target can record a log of
1526 the process execution, and replay it with both forward and reverse
1529 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1530 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1531 set execution-direction {forward|reverse}, for targets that support
1534 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1535 feature is available with a native GDB running on kernel version
1538 * GDB now has support for multi-byte and wide character sets on the
1539 target. Strings whose character type is wchar_t, char16_t, or
1540 char32_t are now correctly printed. GDB supports wide- and unicode-
1541 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1542 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1543 `printf'. This feature requires iconv to work properly; if your
1544 system does not have a working iconv, GDB can use GNU libiconv. See
1545 the installation instructions for more information.
1547 * GDB now supports automatic retrieval of shared library files from
1548 remote targets. To use this feature, specify a system root that begins
1549 with the `remote:' prefix, either via the `set sysroot' command or via
1550 the `--with-sysroot' configure-time option.
1552 * "info sharedlibrary" now takes an optional regex of libraries to show,
1553 and it now reports if a shared library has no debugging information.
1555 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1556 now complete on file names.
1558 * When completing in expressions, gdb will attempt to limit
1559 completions to allowable structure or union fields, where appropriate.
1560 For instance, consider:
1562 # struct example { int f1; double f2; };
1563 # struct example variable;
1566 If the user types TAB at the end of this command line, the available
1567 completions will be "f1" and "f2".
1569 * Inlined functions are now supported. They show up in backtraces, and
1570 the "step", "next", and "finish" commands handle them automatically.
1572 * GDB now supports the token-splicing (##) and stringification (#)
1573 operators when expanding macros. It also supports variable-arity
1576 * GDB now supports inspecting extra signal information, exported by
1577 the new $_siginfo convenience variable. The feature is currently
1578 implemented on linux ARM, i386 and amd64.
1580 * GDB can now display the VFP floating point registers and NEON vector
1581 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1582 can provide these registers (requires Linux 2.6.30 or later). Remote
1583 and simulator targets may also provide them.
1585 * New remote packets
1588 Search memory for a sequence of bytes.
1591 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1592 operation over reliable transport links. Use of this packet is
1593 controlled by the `set remote noack-packet' command.
1596 Kill the process with the specified process ID. Use this in preference
1597 to `k' when multiprocess protocol extensions are supported.
1600 Obtains additional operating system information
1604 Read or write additional signal information.
1606 * Removed remote protocol undocumented extension
1608 An undocumented extension to the remote protocol's `S' stop reply
1609 packet that permited the stub to pass a process id was removed.
1610 Remote servers should use the `T' stop reply packet instead.
1612 * GDB now supports multiple function calling conventions according to the
1613 DWARF-2 DW_AT_calling_convention function attribute.
1615 * The SH target utilizes the aforementioned change to distinguish between gcc
1616 and Renesas calling convention. It also adds the new CLI commands
1617 `set/show sh calling-convention'.
1619 * GDB can now read compressed debug sections, as produced by GNU gold
1620 with the --compress-debug-sections=zlib flag.
1622 * 64-bit core files are now supported on AIX.
1624 * Thread switching is now supported on Tru64.
1626 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1627 which will be allocated using malloc later in program execution.
1629 * The qXfer:libraries:read remote procotol packet now allows passing a
1630 list of section offsets.
1632 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1633 conditions handling signals delivered during attach or thread creation
1634 have also been fixed.
1636 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1637 From the user's standpoint, all unqualified instances of True and False
1638 are treated as the standard definitions, regardless of context.
1640 * GDB now parses C++ symbol and type names more flexibly. For
1643 template<typename T> class C { };
1646 GDB will now correctly handle all of:
1648 ptype C<char const *>
1649 ptype C<char const*>
1650 ptype C<const char *>
1651 ptype C<const char*>
1653 * New features in the GDB remote stub, gdbserver
1655 - The "--wrapper" command-line argument tells gdbserver to use a
1656 wrapper program to launch programs for debugging.
1658 - On PowerPC and S/390 targets, it is now possible to use a single
1659 gdbserver executable to debug both 32-bit and 64-bit programs.
1660 (This requires gdbserver itself to be built as a 64-bit executable.)
1662 - gdbserver uses the new noack protocol mode for TCP connections to
1663 reduce communications latency, if also supported and enabled in GDB.
1665 - Support for the sparc64-linux-gnu target is now included in
1668 - The amd64-linux build of gdbserver now supports debugging both
1669 32-bit and 64-bit programs.
1671 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1672 now support hardware watchpoints, and will use them automatically
1677 GDB now has support for scripting using Python. Whether this is
1678 available is determined at configure time.
1680 New GDB commands can now be written in Python.
1682 * Ada tasking support
1684 Ada tasks can now be inspected in GDB. The following commands have
1688 Print the list of Ada tasks.
1690 Print detailed information about task number N.
1692 Print the task number of the current task.
1694 Switch the context of debugging to task number N.
1696 * Support for user-defined prefixed commands. The "define" command can
1697 add new commands to existing prefixes, e.g. "target".
1699 * Multi-inferior, multi-process debugging.
1701 GDB now has generalized support for multi-inferior debugging. See
1702 "Debugging Multiple Inferiors" in the manual for more information.
1703 Although availability still depends on target support, the command
1704 set is more uniform now. The GNU/Linux specific multi-forks support
1705 has been migrated to this new framework. This implied some user
1706 visible changes; see "New commands" and also "Removed commands"
1709 * Target descriptions can now describe the target OS ABI. See the
1710 "Target Description Format" section in the user manual for more
1713 * Target descriptions can now describe "compatible" architectures
1714 to indicate that the target can execute applications for a different
1715 architecture in addition to those for the main target architecture.
1716 See the "Target Description Format" section in the user manual for
1719 * Multi-architecture debugging.
1721 GDB now includes general supports for debugging applications on
1722 hybrid systems that use more than one single processor architecture
1723 at the same time. Each such hybrid architecture still requires
1724 specific support to be added. The only hybrid architecture supported
1725 in this version of GDB is the Cell Broadband Engine.
1727 * GDB now supports integrated debugging of Cell/B.E. applications that
1728 use both the PPU and SPU architectures. To enable support for hybrid
1729 Cell/B.E. debugging, you need to configure GDB to support both the
1730 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1731 --enable-targets configure option.
1733 * Non-stop mode debugging.
1735 For some targets, GDB now supports an optional mode of operation in
1736 which you can examine stopped threads while other threads continue
1737 to execute freely. This is referred to as non-stop mode, with the
1738 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1739 section in the user manual for more information.
1741 To be able to support remote non-stop debugging, a remote stub needs
1742 to implement the non-stop mode remote protocol extensions, as
1743 described in the "Remote Non-Stop" section of the user manual. The
1744 GDB remote stub, gdbserver, has been adjusted to support these
1745 extensions on linux targets.
1747 * New commands (for set/show, see "New options" below)
1749 catch syscall [NAME(S) | NUMBER(S)]
1750 Catch system calls. Arguments, which should be names of system
1751 calls or their numbers, mean catch only those syscalls. Without
1752 arguments, every syscall will be caught. When the inferior issues
1753 any of the specified syscalls, GDB will stop and announce the system
1754 call, both when it is called and when its call returns. This
1755 feature is currently available with a native GDB running on the
1756 Linux Kernel, under the following architectures: x86, x86_64,
1757 PowerPC and PowerPC64.
1759 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1761 Search memory for a sequence of bytes.
1763 maint set python print-stack
1764 maint show python print-stack
1765 Show a stack trace when an error is encountered in a Python script.
1768 Invoke CODE by passing it to the Python interpreter.
1773 These allow macros to be defined, undefined, and listed
1777 Show operating system information about processes.
1780 List the inferiors currently under GDB's control.
1783 Switch focus to inferior number NUM.
1786 Detach from inferior number NUM.
1789 Kill inferior number NUM.
1793 set spu stop-on-load
1794 show spu stop-on-load
1795 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1797 set spu auto-flush-cache
1798 show spu auto-flush-cache
1799 Control whether to automatically flush the software-managed cache
1800 during Cell/B.E. debugging.
1802 set sh calling-convention
1803 show sh calling-convention
1804 Control the calling convention used when calling SH target functions.
1807 show debug timestamp
1808 Control display of timestamps with GDB debugging output.
1810 set disassemble-next-line
1811 show disassemble-next-line
1812 Control display of disassembled source lines or instructions when
1815 set remote noack-packet
1816 show remote noack-packet
1817 Set/show the use of remote protocol QStartNoAckMode packet. See above
1818 under "New remote packets."
1820 set remote query-attached-packet
1821 show remote query-attached-packet
1822 Control use of remote protocol `qAttached' (query-attached) packet.
1824 set remote read-siginfo-object
1825 show remote read-siginfo-object
1826 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1829 set remote write-siginfo-object
1830 show remote write-siginfo-object
1831 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1834 set remote reverse-continue
1835 show remote reverse-continue
1836 Control use of remote protocol 'bc' (reverse-continue) packet.
1838 set remote reverse-step
1839 show remote reverse-step
1840 Control use of remote protocol 'bs' (reverse-step) packet.
1842 set displaced-stepping
1843 show displaced-stepping
1844 Control displaced stepping mode. Displaced stepping is a way to
1845 single-step over breakpoints without removing them from the debuggee.
1846 Also known as "out-of-line single-stepping".
1849 show debug displaced
1850 Control display of debugging info for displaced stepping.
1852 maint set internal-error
1853 maint show internal-error
1854 Control what GDB does when an internal error is detected.
1856 maint set internal-warning
1857 maint show internal-warning
1858 Control what GDB does when an internal warning is detected.
1863 Use a wrapper program to launch programs for debugging.
1865 set multiple-symbols (all|ask|cancel)
1866 show multiple-symbols
1867 The value of this variable can be changed to adjust the debugger behavior
1868 when an expression or a breakpoint location contains an ambiguous symbol
1869 name (an overloaded function name, for instance).
1871 set breakpoint always-inserted
1872 show breakpoint always-inserted
1873 Keep breakpoints always inserted in the target, as opposed to inserting
1874 them when resuming the target, and removing them when the target stops.
1875 This option can improve debugger performance on slow remote targets.
1877 set arm fallback-mode (arm|thumb|auto)
1878 show arm fallback-mode
1879 set arm force-mode (arm|thumb|auto)
1881 These commands control how ARM GDB determines whether instructions
1882 are ARM or Thumb. The default for both settings is auto, which uses
1883 the current CPSR value for instructions without symbols; previous
1884 versions of GDB behaved as if "set arm fallback-mode arm".
1886 set disable-randomization
1887 show disable-randomization
1888 Standalone programs run with the virtual address space randomization enabled
1889 by default on some platforms. This option keeps the addresses stable across
1890 multiple debugging sessions.
1894 Control whether other threads are stopped or not when some thread hits
1899 Requests that asynchronous execution is enabled in the target, if available.
1900 In this case, it's possible to resume target in the background, and interact
1901 with GDB while the target is running. "show target-async" displays the
1902 current state of asynchronous execution of the target.
1904 set target-wide-charset
1905 show target-wide-charset
1906 The target-wide-charset is the name of the character set that GDB
1907 uses when printing characters whose type is wchar_t.
1909 set tcp auto-retry (on|off)
1911 set tcp connect-timeout
1912 show tcp connect-timeout
1913 These commands allow GDB to retry failed TCP connections to a remote stub
1914 with a specified timeout period; this is useful if the stub is launched
1915 in parallel with GDB but may not be ready to accept connections immediately.
1917 set libthread-db-search-path
1918 show libthread-db-search-path
1919 Control list of directories which GDB will search for appropriate
1922 set schedule-multiple (on|off)
1923 show schedule-multiple
1924 Allow GDB to resume all threads of all processes or only threads of
1925 the current process.
1929 Use more aggressive caching for accesses to the stack. This improves
1930 performance of remote debugging (particularly backtraces) without
1931 affecting correctness.
1933 set interactive-mode (on|off|auto)
1934 show interactive-mode
1935 Control whether GDB runs in interactive mode (on) or not (off).
1936 When in interactive mode, GDB waits for the user to answer all
1937 queries. Otherwise, GDB does not wait and assumes the default
1938 answer. When set to auto (the default), GDB determines which
1939 mode to use based on the stdin settings.
1944 For program forks, this is replaced by the new more generic `info
1945 inferiors' command. To list checkpoints, you can still use the
1946 `info checkpoints' command, which was an alias for the `info forks'
1950 Replaced by the new `inferior' command. To switch between
1951 checkpoints, you can still use the `restart' command, which was an
1952 alias for the `fork' command.
1955 This is removed, since some targets don't have a notion of
1956 processes. To switch between processes, you can still use the
1957 `inferior' command using GDB's own inferior number.
1960 For program forks, this is replaced by the new more generic `kill
1961 inferior' command. To delete a checkpoint, you can still use the
1962 `delete checkpoint' command, which was an alias for the `delete
1966 For program forks, this is replaced by the new more generic `detach
1967 inferior' command. To detach a checkpoint, you can still use the
1968 `detach checkpoint' command, which was an alias for the `detach
1971 * New native configurations
1973 x86/x86_64 Darwin i[34567]86-*-darwin*
1975 x86_64 MinGW x86_64-*-mingw*
1979 Lattice Mico32 lm32-*
1980 x86 DICOS i[34567]86-*-dicos*
1981 x86_64 DICOS x86_64-*-dicos*
1984 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1985 (mingw32ce) debugging.
1991 These commands were actually not implemented on any target.
1993 *** Changes in GDB 6.8
1995 * New native configurations
1997 NetBSD/hppa hppa*-*netbsd*
1998 Xtensa GNU/Linux xtensa*-*-linux*
2002 NetBSD/hppa hppa*-*-netbsd*
2003 Xtensa GNU/Lunux xtensa*-*-linux*
2005 * Change in command line behavior -- corefiles vs. process ids.
2007 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2008 attaching to process NUMBER fails, GDB no longer attempts to open a
2009 core file named NUMBER. Attaching to a program using the -c option
2010 is no longer supported. Instead, use the '-p' or '--pid' options.
2012 * GDB can now be built as a native debugger for debugging Windows x86
2013 (mingw32) Portable Executable (PE) programs.
2015 * Pending breakpoints no longer change their number when their address
2018 * GDB now supports breakpoints with multiple locations,
2019 including breakpoints on C++ constructors, inside C++ templates,
2020 and in inlined functions.
2022 * GDB's ability to debug optimized code has been improved. GDB more
2023 accurately identifies function bodies and lexical blocks that occupy
2024 more than one contiguous range of addresses.
2026 * Target descriptions can now describe registers for PowerPC.
2028 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2029 registers on PowerPC targets.
2031 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2032 targets even when the libthread_db library is not available.
2034 * The GDB remote stub, gdbserver, now supports the new file transfer
2035 commands (remote put, remote get, and remote delete).
2037 * The GDB remote stub, gdbserver, now supports run and attach in
2038 extended-remote mode.
2040 * hppa*64*-*-hpux11* target broken
2041 The debugger is unable to start a program and fails with the following
2042 error: "Error trying to get information about dynamic linker".
2043 The gdb-6.7 release is also affected.
2045 * GDB now supports the --enable-targets= configure option to allow
2046 building a single GDB executable that supports multiple remote
2047 target architectures.
2049 * GDB now supports debugging C and C++ programs which use the
2050 Decimal Floating Point extension. In addition, the PowerPC target
2051 now has a set of pseudo-registers to inspect decimal float values
2052 stored in two consecutive float registers.
2054 * The -break-insert MI command can optionally create pending
2057 * Improved support for debugging Ada
2058 Many improvements to the Ada language support have been made. These
2060 - Better support for Ada2005 interface types
2061 - Improved handling of arrays and slices in general
2062 - Better support for Taft-amendment types
2063 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2065 - Improved command completion in Ada
2068 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2073 set print frame-arguments (all|scalars|none)
2074 show print frame-arguments
2075 The value of this variable can be changed to control which argument
2076 values should be printed by the debugger when displaying a frame.
2081 Transfer files to and from a remote target, and delete remote files.
2088 Transfer files to and from a remote target, and delete remote files.
2090 * New remote packets
2097 Open, close, read, write, and delete files on the remote system.
2100 Attach to an existing process on the remote system, in extended-remote
2104 Run a new process on the remote system, in extended-remote mode.
2106 *** Changes in GDB 6.7
2108 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2109 bfd, libiberty and opcodes, as revealed by static analysis donated by
2110 Coverity, Inc. (http://scan.coverity.com).
2112 * When looking up multiply-defined global symbols, GDB will now prefer the
2113 symbol definition in the current shared library if it was built using the
2114 -Bsymbolic linker option.
2116 * When the Text User Interface (TUI) is not configured, GDB will now
2117 recognize the -tui command-line option and print a message that the TUI
2120 * The GDB remote stub, gdbserver, now has lower overhead for high
2121 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2123 * GDB for MIPS targets now autodetects whether a remote target provides
2124 32-bit or 64-bit register values.
2126 * Support for C++ member pointers has been improved.
2128 * GDB now understands XML target descriptions, which specify the
2129 target's overall architecture. GDB can read a description from
2130 a local file or over the remote serial protocol.
2132 * Vectors of single-byte data use a new integer type which is not
2133 automatically displayed as character or string data.
2135 * The /s format now works with the print command. It displays
2136 arrays of single-byte integers and pointers to single-byte integers
2139 * Target descriptions can now describe target-specific registers,
2140 for architectures which have implemented the support (currently
2141 only ARM, M68K, and MIPS).
2143 * GDB and the GDB remote stub, gdbserver, now support the XScale
2146 * The GDB remote stub, gdbserver, has been updated to support
2147 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2148 has been rewritten to use the standard GDB remote protocol.
2150 * GDB can now step into C++ functions which are called through thunks.
2152 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2154 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2155 layout. It also supports a TextSeg= and DataSeg= response when only
2156 segment base addresses (rather than offsets) are available.
2158 * The /i format now outputs any trailing branch delay slot instructions
2159 immediately following the last instruction within the count specified.
2161 * The GDB remote protocol "T" stop reply packet now supports a
2162 "library" response. Combined with the new "qXfer:libraries:read"
2163 packet, this response allows GDB to debug shared libraries on targets
2164 where the operating system manages the list of loaded libraries (e.g.
2165 Windows and SymbianOS).
2167 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2168 (DLLs) on Windows and Windows CE targets.
2170 * GDB now supports a faster verification that a .debug file matches its binary
2171 according to its build-id signature, if the signature is present.
2177 Enable or disable hardware flow control (RTS/CTS) on the serial port
2178 when debugging using remote targets.
2180 set mem inaccessible-by-default
2181 show mem inaccessible-by-default
2182 If the target supplies a memory map, for instance via the remote
2183 protocol's "qXfer:memory-map:read" packet, setting this variable
2184 prevents GDB from accessing memory outside the memory map. This
2185 is useful for targets with memory mapped registers or which react
2186 badly to accesses of unmapped address space.
2188 set breakpoint auto-hw
2189 show breakpoint auto-hw
2190 If the target supplies a memory map, for instance via the remote
2191 protocol's "qXfer:memory-map:read" packet, setting this variable
2192 lets GDB use hardware breakpoints automatically for memory regions
2193 where it can not use software breakpoints. This covers both the
2194 "break" command and internal breakpoints used for other commands
2195 including "next" and "finish".
2198 catch exception unhandled
2199 Stop the program execution when Ada exceptions are raised.
2202 Stop the program execution when an Ada assertion failed.
2206 Set an alternate system root for target files. This is a more
2207 general version of "set solib-absolute-prefix", which is now
2208 an alias to "set sysroot".
2211 Provide extended SPU facility status information. This set of
2212 commands is available only when debugging the Cell/B.E. SPU
2215 * New native configurations
2217 OpenBSD/sh sh*-*openbsd*
2220 unset tdesc filename
2222 Use the specified local file as an XML target description, and do
2223 not query the target for its built-in description.
2227 OpenBSD/sh sh*-*-openbsd*
2228 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2229 Toshiba Media Processor mep-elf
2231 * New remote packets
2234 Ignore the specified signals; pass them directly to the debugged program
2235 without stopping other threads or reporting them to GDB.
2237 qXfer:features:read:
2238 Read an XML target description from the target, which describes its
2243 Read or write contents of an spufs file on the target system. These
2244 packets are available only on the Cell/B.E. SPU architecture.
2246 qXfer:libraries:read:
2247 Report the loaded shared libraries. Combined with new "T" packet
2248 response, this packet allows GDB to debug shared libraries on
2249 targets where the operating system manages the list of loaded
2250 libraries (e.g. Windows and SymbianOS).
2254 Support for these obsolete configurations has been removed.
2262 i[34567]86-*-lynxos*
2263 i[34567]86-*-netware*
2264 i[34567]86-*-sco3.2v5*
2265 i[34567]86-*-sco3.2v4*
2267 i[34567]86-*-sysv4.2*
2270 i[34567]86-*-unixware2*
2271 i[34567]86-*-unixware*
2280 * Other removed features
2287 Various m68k-only ROM monitors.
2294 Various Renesas ROM monitors and debugging interfaces for SH and
2299 Support for a Macraigor serial interface to on-chip debugging.
2300 GDB does not directly support the newer parallel or USB
2305 A debug information format. The predecessor to DWARF 2 and
2306 DWARF 3, which are still supported.
2308 Support for the HP aCC compiler on HP-UX/PA-RISC
2310 SOM-encapsulated symbolic debugging information, automatic
2311 invocation of pxdb, and the aCC custom C++ ABI. This does not
2312 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2313 with aCC can still be debugged on an assembly level.
2315 MIPS ".pdr" sections
2317 A MIPS-specific format used to describe stack frame layout
2318 in debugging information.
2322 GDB could work with an older version of Guile to debug
2323 the interpreter and Scheme programs running in it.
2325 set mips stack-arg-size
2326 set mips saved-gpreg-size
2328 Use "set mips abi" to control parameter passing for MIPS.
2330 *** Changes in GDB 6.6
2335 Cell Broadband Engine SPU spu-elf
2337 * GDB can now be configured as a cross-debugger targeting native Windows
2338 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2339 running on a Windows system over TCP/IP to debug Windows programs.
2341 * The GDB remote stub, gdbserver, has been updated to support Windows and
2342 Cygwin debugging. Both single-threaded and multi-threaded programs are
2345 * The "set trust-readonly-sections" command works again. This command was
2346 broken in GDB 6.3, 6.4, and 6.5.
2348 * The "load" command now supports writing to flash memory, if the remote
2349 stub provides the required support.
2351 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2352 longer requires symbolic debug information (e.g. DWARF-2).
2357 unset substitute-path
2358 show substitute-path
2359 Manage a list of substitution rules that GDB uses to rewrite the name
2360 of the directories where the sources are located. This can be useful
2361 for instance when the sources were moved to a different location
2362 between compilation and debugging.
2366 Print each CLI command as it is executed. Each command is prefixed with
2367 a number of `+' symbols representing the nesting depth.
2368 The source command now has a `-v' option to enable the same feature.
2372 The ARM Demon monitor support (RDP protocol, "target rdp").
2374 Kernel Object Display, an embedded debugging feature which only worked with
2375 an obsolete version of Cisco IOS.
2377 The 'set download-write-size' and 'show download-write-size' commands.
2379 * New remote packets
2382 Tell a stub about GDB client features, and request remote target features.
2383 The first feature implemented is PacketSize, which allows the target to
2384 specify the size of packets it can handle - to minimize the number of
2385 packets required and improve performance when connected to a remote
2389 Fetch an OS auxilliary vector from the remote stub. This packet is a
2390 more efficient replacement for qPart:auxv:read.
2392 qXfer:memory-map:read:
2393 Fetch a memory map from the remote stub, including information about
2394 RAM, ROM, and flash memory devices.
2399 Erase and program a flash memory device.
2401 * Removed remote packets
2404 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2405 used it, and only gdbserver implemented it.
2407 *** Changes in GDB 6.5
2411 Renesas M32C/M16C m32c-elf
2413 Morpho Technologies ms1 ms1-elf
2417 init-if-undefined Initialize a convenience variable, but
2418 only if it doesn't already have a value.
2420 The following commands are presently only implemented for native GNU/Linux:
2422 checkpoint Save a snapshot of the program state.
2424 restart <n> Return the program state to a
2425 previously saved state.
2427 info checkpoints List currently saved checkpoints.
2429 delete-checkpoint <n> Delete a previously saved checkpoint.
2431 set|show detach-on-fork Tell gdb whether to detach from a newly
2432 forked process, or to keep debugging it.
2434 info forks List forks of the user program that
2435 are available to be debugged.
2437 fork <n> Switch to debugging one of several
2438 forks of the user program that are
2439 available to be debugged.
2441 delete-fork <n> Delete a fork from the list of forks
2442 that are available to be debugged (and
2443 kill the forked process).
2445 detach-fork <n> Delete a fork from the list of forks
2446 that are available to be debugged (and
2447 allow the process to continue).
2451 Morpho Technologies ms2 ms1-elf
2453 * Improved Windows host support
2455 GDB now builds as a cross debugger hosted on i686-mingw32, including
2456 native console support, and remote communications using either
2457 network sockets or serial ports.
2459 * Improved Modula-2 language support
2461 GDB can now print most types in the Modula-2 syntax. This includes:
2462 basic types, set types, record types, enumerated types, range types,
2463 pointer types and ARRAY types. Procedure var parameters are correctly
2464 printed and hexadecimal addresses and character constants are also
2465 written in the Modula-2 syntax. Best results can be obtained by using
2466 GNU Modula-2 together with the -gdwarf-2 command line option.
2470 The ARM rdi-share module.
2472 The Netware NLM debug server.
2474 *** Changes in GDB 6.4
2476 * New native configurations
2478 OpenBSD/arm arm*-*-openbsd*
2479 OpenBSD/mips64 mips64-*-openbsd*
2483 Morpho Technologies ms1 ms1-elf
2485 * New command line options
2487 --batch-silent As for --batch, but totally silent.
2488 --return-child-result The debugger will exist with the same value
2489 the child (debugged) program exited with.
2490 --eval-command COMMAND, -ex COMMAND
2491 Execute a single GDB CLI command. This may be
2492 specified multiple times and in conjunction
2493 with the --command (-x) option.
2495 * Deprecated commands removed
2497 The following commands, that were deprecated in 2000, have been
2501 set|show arm disassembly-flavor set|show arm disassembler
2502 othernames set arm disassembler
2503 set|show remotedebug set|show debug remote
2504 set|show archdebug set|show debug arch
2505 set|show eventdebug set|show debug event
2508 * New BSD user-level threads support
2510 It is now possible to debug programs using the user-level threads
2511 library on OpenBSD and FreeBSD. Currently supported (target)
2514 FreeBSD/amd64 x86_64-*-freebsd*
2515 FreeBSD/i386 i386-*-freebsd*
2516 OpenBSD/i386 i386-*-openbsd*
2518 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2519 are not yet supported.
2521 * New support for Matsushita MN10300 w/sim added
2522 (Work in progress). mn10300-elf.
2524 * REMOVED configurations and files
2526 VxWorks and the XDR protocol *-*-vxworks
2527 Motorola MCORE mcore-*-*
2528 National Semiconductor NS32000 ns32k-*-*
2530 * New "set print array-indexes" command
2532 After turning this setting "on", GDB prints the index of each element
2533 when displaying arrays. The default is "off" to preserve the previous
2536 * VAX floating point support
2538 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2540 * User-defined command support
2542 In addition to using $arg0..$arg9 for argument passing, it is now possible
2543 to use $argc to determine now many arguments have been passed. See the
2544 section on user-defined commands in the user manual for more information.
2546 *** Changes in GDB 6.3:
2548 * New command line option
2550 GDB now accepts -l followed by a number to set the timeout for remote
2553 * GDB works with GCC -feliminate-dwarf2-dups
2555 GDB now supports a more compact representation of DWARF-2 debug
2556 information using DW_FORM_ref_addr references. These are produced
2557 by GCC with the option -feliminate-dwarf2-dups and also by some
2558 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2559 to use -feliminate-dwarf2-dups.
2561 * Internationalization
2563 When supported by the host system, GDB will be built with
2564 internationalization (libintl). The task of marking up the sources is
2565 continued, we're looking forward to our first translation.
2569 Initial support for debugging programs compiled with the GNAT
2570 implementation of the Ada programming language has been integrated
2571 into GDB. In this release, support is limited to expression evaluation.
2573 * New native configurations
2575 GNU/Linux/m32r m32r-*-linux-gnu
2579 GDB's remote protocol now includes support for the 'p' packet. This
2580 packet is used to fetch individual registers from a remote inferior.
2582 * END-OF-LIFE registers[] compatibility module
2584 GDB's internal register infrastructure has been completely rewritten.
2585 The new infrastructure making possible the implementation of key new
2586 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2589 GDB 6.3 will be the last release to include the the registers[]
2590 compatibility module that allowed out-of-date configurations to
2591 continue to work. This change directly impacts the following
2601 powerpc bdm protocol
2603 Unless there is activity to revive these configurations, they will be
2604 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2606 * OBSOLETE configurations and files
2608 Configurations that have been declared obsolete in this release have
2609 been commented out. Unless there is activity to revive these
2610 configurations, the next release of GDB will have their sources
2611 permanently REMOVED.
2620 *** Changes in GDB 6.2.1:
2622 * MIPS `break main; run' gave an heuristic-fence-post warning
2624 When attempting to run even a simple program, a warning about
2625 heuristic-fence-post being hit would be reported. This problem has
2628 * MIPS IRIX 'long double' crashed GDB
2630 When examining a long double variable, GDB would get a segmentation
2631 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2632 IRIX long double values).
2636 A bug in the VAX stack code was causing problems with the "next"
2637 command. This problem has been fixed.
2639 *** Changes in GDB 6.2:
2641 * Fix for ``many threads''
2643 On GNU/Linux systems that use the NPTL threads library, a program
2644 rapidly creating and deleting threads would confuse GDB leading to the
2647 ptrace: No such process.
2648 thread_db_get_info: cannot get thread info: generic error
2650 This problem has been fixed.
2652 * "-async" and "-noasync" options removed.
2654 Support for the broken "-noasync" option has been removed (it caused
2657 * New ``start'' command.
2659 This command runs the program until the begining of the main procedure.
2661 * New BSD Kernel Data Access Library (libkvm) interface
2663 Using ``target kvm'' it is now possible to debug kernel core dumps and
2664 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2665 platforms. Currently supported (native-only) configurations are:
2667 FreeBSD/amd64 x86_64-*-freebsd*
2668 FreeBSD/i386 i?86-*-freebsd*
2669 NetBSD/i386 i?86-*-netbsd*
2670 NetBSD/m68k m68*-*-netbsd*
2671 NetBSD/sparc sparc-*-netbsd*
2672 OpenBSD/amd64 x86_64-*-openbsd*
2673 OpenBSD/i386 i?86-*-openbsd*
2674 OpenBSD/m68k m68*-openbsd*
2675 OpenBSD/sparc sparc-*-openbsd*
2677 * Signal trampoline code overhauled
2679 Many generic problems with GDB's signal handling code have been fixed.
2680 These include: backtraces through non-contiguous stacks; recognition
2681 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2682 call; backtrace through a signal trampoline; step into and out of
2683 signal handlers; and single-stepping in the signal trampoline.
2685 Please note that kernel bugs are a limiting factor here. These
2686 features have been shown to work on an s390 GNU/Linux system that
2687 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2689 * Cygwin support for DWARF 2 added.
2691 * New native configurations
2693 GNU/Linux/hppa hppa*-*-linux*
2694 OpenBSD/hppa hppa*-*-openbsd*
2695 OpenBSD/m68k m68*-*-openbsd*
2696 OpenBSD/m88k m88*-*-openbsd*
2697 OpenBSD/powerpc powerpc-*-openbsd*
2698 NetBSD/vax vax-*-netbsd*
2699 OpenBSD/vax vax-*-openbsd*
2701 * END-OF-LIFE frame compatibility module
2703 GDB's internal frame infrastructure has been completely rewritten.
2704 The new infrastructure making it possible to support key new features
2705 including DWARF 2 Call Frame Information. To aid in the task of
2706 migrating old configurations to this new infrastructure, a
2707 compatibility module, that allowed old configurations to continue to
2708 work, was also included.
2710 GDB 6.2 will be the last release to include this frame compatibility
2711 module. This change directly impacts the following configurations:
2721 Unless there is activity to revive these configurations, they will be
2722 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2724 * REMOVED configurations and files
2726 Sun 3, running SunOS 3 m68*-*-sunos3*
2727 Sun 3, running SunOS 4 m68*-*-sunos4*
2728 Sun 2, running SunOS 3 m68000-*-sunos3*
2729 Sun 2, running SunOS 4 m68000-*-sunos4*
2730 Motorola 680x0 running LynxOS m68*-*-lynxos*
2731 AT&T 3b1/Unix pc m68*-att-*
2732 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2733 decstation mips-dec-* mips-little-*
2734 riscos mips-*-riscos* mips-*-sysv*
2735 sonymips mips-sony-*
2736 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2738 *** Changes in GDB 6.1.1:
2740 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2742 The TUI (Text-mode User Interface) is now built as part of a default
2743 GDB configuration. It is enabled by either selecting the TUI with the
2744 command line option "-i=tui" or by running the separate "gdbtui"
2745 program. For more information on the TUI, see the manual "Debugging
2748 * Pending breakpoint support (also included in GDB 6.1)
2750 Support has been added to allow you to specify breakpoints in shared
2751 libraries that have not yet been loaded. If a breakpoint location
2752 cannot be found, and the "breakpoint pending" option is set to auto,
2753 GDB queries you if you wish to make the breakpoint pending on a future
2754 shared-library load. If and when GDB resolves the breakpoint symbol,
2755 the pending breakpoint is removed as one or more regular breakpoints
2758 Pending breakpoints are very useful for GCJ Java debugging.
2760 * Fixed ISO-C build problems
2762 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2763 non ISO-C code that stopped them being built using a more strict ISO-C
2764 compiler (e.g., IBM's C compiler).
2766 * Fixed build problem on IRIX 5
2768 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2769 wasn't able to compile compile on an IRIX 5 system.
2771 * Added execute permission to gdb/gdbserver/configure
2773 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2774 permission. This bug would cause configure to fail on a number of
2775 systems (Solaris, IRIX). Ref: server/519.
2777 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2779 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2780 has been updated to use constant array sizes.
2782 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2784 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2785 its generated DWARF Call Frame Info. This encoding was causing GDB to
2786 panic, that panic has been fixed. Ref: gdb/1628.
2788 * Fixed a problem when examining parameters in shared library code.
2790 When examining parameters in optimized shared library code generated
2791 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2792 not available''. GDB now correctly displays the variable's value.
2794 *** Changes in GDB 6.1:
2796 * Removed --with-mmalloc
2798 Support for the mmalloc memory manager has been removed, as it
2799 conflicted with the internal gdb byte cache.
2801 * Changes in AMD64 configurations
2803 The AMD64 target now includes the %cs and %ss registers. As a result
2804 the AMD64 remote protocol has changed; this affects the floating-point
2805 and SSE registers. If you rely on those registers for your debugging,
2806 you should upgrade gdbserver on the remote side.
2808 * Revised SPARC target
2810 The SPARC target has been completely revised, incorporating the
2811 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2812 support for LynxOS and SunOS 4 has been dropped. Calling functions
2813 from within GDB on operating systems with a non-executable stack
2814 (Solaris, OpenBSD) now works.
2818 GDB has a new C++ demangler which does a better job on the mangled
2819 names generated by current versions of g++. It also runs faster, so
2820 with this and other changes gdb should now start faster on large C++
2823 * DWARF 2 Location Expressions
2825 GDB support for location expressions has been extended to support function
2826 arguments and frame bases. Older versions of GDB could crash when they
2829 * C++ nested types and namespaces
2831 GDB's support for nested types and namespaces in C++ has been
2832 improved, especially if you use the DWARF 2 debugging format. (This
2833 is the default for recent versions of GCC on most platforms.)
2834 Specifically, if you have a class "Inner" defined within a class or
2835 namespace "Outer", then GDB realizes that the class's name is
2836 "Outer::Inner", not simply "Inner". This should greatly reduce the
2837 frequency of complaints about not finding RTTI symbols. In addition,
2838 if you are stopped at inside of a function defined within a namespace,
2839 GDB modifies its name lookup accordingly.
2841 * New native configurations
2843 NetBSD/amd64 x86_64-*-netbsd*
2844 OpenBSD/amd64 x86_64-*-openbsd*
2845 OpenBSD/alpha alpha*-*-openbsd*
2846 OpenBSD/sparc sparc-*-openbsd*
2847 OpenBSD/sparc64 sparc64-*-openbsd*
2849 * New debugging protocols
2851 M32R with SDI protocol m32r-*-elf*
2853 * "set prompt-escape-char" command deleted.
2855 The command "set prompt-escape-char" has been deleted. This command,
2856 and its very obscure effet on GDB's prompt, was never documented,
2857 tested, nor mentioned in the NEWS file.
2859 * OBSOLETE configurations and files
2861 Configurations that have been declared obsolete in this release have
2862 been commented out. Unless there is activity to revive these
2863 configurations, the next release of GDB will have their sources
2864 permanently REMOVED.
2866 Sun 3, running SunOS 3 m68*-*-sunos3*
2867 Sun 3, running SunOS 4 m68*-*-sunos4*
2868 Sun 2, running SunOS 3 m68000-*-sunos3*
2869 Sun 2, running SunOS 4 m68000-*-sunos4*
2870 Motorola 680x0 running LynxOS m68*-*-lynxos*
2871 AT&T 3b1/Unix pc m68*-att-*
2872 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2873 decstation mips-dec-* mips-little-*
2874 riscos mips-*-riscos* mips-*-sysv*
2875 sonymips mips-sony-*
2876 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2878 * REMOVED configurations and files
2880 SGI Irix-4.x mips-sgi-irix4 or iris4
2881 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2882 Z8000 simulator z8k-zilog-none or z8ksim
2883 Matsushita MN10200 w/simulator mn10200-*-*
2884 H8/500 simulator h8500-hitachi-hms or h8500hms
2885 HP/PA running BSD hppa*-*-bsd*
2886 HP/PA running OSF/1 hppa*-*-osf*
2887 HP/PA Pro target hppa*-*-pro*
2888 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2889 386BSD i[3456]86-*-bsd*
2890 Sequent family i[3456]86-sequent-sysv4*
2891 i[3456]86-sequent-sysv*
2892 i[3456]86-sequent-bsd*
2893 SPARC running LynxOS sparc-*-lynxos*
2894 SPARC running SunOS 4 sparc-*-sunos4*
2895 Tsqware Sparclet sparclet-*-*
2896 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2898 *** Changes in GDB 6.0:
2902 Support for debugging the Objective-C programming language has been
2903 integrated into GDB.
2905 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2907 DWARF 2's Call Frame Information makes available compiler generated
2908 information that more exactly describes the program's run-time stack.
2909 By using this information, GDB is able to provide more robust stack
2912 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2913 have been updated to use a new backtrace mechanism which includes
2914 DWARF 2 CFI support.
2918 GDB's remote protocol has been extended to include support for hosted
2919 file I/O (where the remote target uses GDB's file system). See GDB's
2920 remote protocol documentation for details.
2922 * All targets using the new architecture framework.
2924 All of GDB's targets have been updated to use the new internal
2925 architecture framework. The way is now open for future GDB releases
2926 to include cross-architecture native debugging support (i386 on amd64,
2929 * GNU/Linux's Thread Local Storage (TLS)
2931 GDB now includes support for for the GNU/Linux implementation of
2932 per-thread variables.
2934 * GNU/Linux's Native POSIX Thread Library (NPTL)
2936 GDB's thread code has been updated to work with either the new
2937 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2939 * Separate debug info.
2941 GDB, in conjunction with BINUTILS, now supports a mechanism for
2942 automatically loading debug information from a separate file. Instead
2943 of shipping full debug and non-debug versions of system libraries,
2944 system integrators can now instead ship just the stripped libraries
2945 and optional debug files.
2947 * DWARF 2 Location Expressions
2949 DWARF 2 Location Expressions allow the compiler to more completely
2950 describe the location of variables (even in optimized code) to the
2953 GDB now includes preliminary support for location expressions (support
2954 for DW_OP_piece is still missing).
2958 A number of long standing bugs that caused GDB to die while starting a
2959 Java application have been fixed. GDB's Java support is now
2960 considered "useable".
2962 * GNU/Linux support for fork, vfork, and exec.
2964 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2965 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2968 * GDB supports logging output to a file
2970 There are two new commands, "set logging" and "show logging", which can be
2971 used to capture GDB's output to a file.
2973 * The meaning of "detach" has changed for gdbserver
2975 The "detach" command will now resume the application, as documented. To
2976 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2979 * d10v, m68hc11 `regs' command deprecated
2981 The `info registers' command has been updated so that it displays the
2982 registers using a format identical to the old `regs' command.
2986 A new command, "maint set profile on/off", has been added. This command can
2987 be used to enable or disable profiling while running GDB, to profile a
2988 session or a set of commands. In addition there is a new configure switch,
2989 "--enable-profiling", which will cause GDB to be compiled with profiling
2990 data, for more informative profiling results.
2992 * Default MI syntax changed to "mi2".
2994 The default MI (machine interface) syntax, enabled by the command line
2995 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2996 "mi1", can be enabled by specifying the option "-i=mi1".
2998 Support for the original "mi0" syntax (included in GDB 5.0) has been
3001 Fix for gdb/192: removed extraneous space when displaying frame level.
3002 Fix for gdb/672: update changelist is now output in mi list format.
3003 Fix for gdb/702: a -var-assign that updates the value now shows up
3004 in a subsequent -var-update.
3006 * New native configurations.
3008 FreeBSD/amd64 x86_64-*-freebsd*
3010 * Multi-arched targets.
3012 HP/PA HPUX11 hppa*-*-hpux*
3013 Renesas M32R/D w/simulator m32r-*-elf*
3015 * OBSOLETE configurations and files
3017 Configurations that have been declared obsolete in this release have
3018 been commented out. Unless there is activity to revive these
3019 configurations, the next release of GDB will have their sources
3020 permanently REMOVED.
3022 Z8000 simulator z8k-zilog-none or z8ksim
3023 Matsushita MN10200 w/simulator mn10200-*-*
3024 H8/500 simulator h8500-hitachi-hms or h8500hms
3025 HP/PA running BSD hppa*-*-bsd*
3026 HP/PA running OSF/1 hppa*-*-osf*
3027 HP/PA Pro target hppa*-*-pro*
3028 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3029 Sequent family i[3456]86-sequent-sysv4*
3030 i[3456]86-sequent-sysv*
3031 i[3456]86-sequent-bsd*
3032 Tsqware Sparclet sparclet-*-*
3033 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3035 * REMOVED configurations and files
3038 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3039 IBM AIX PS/2 i[3456]86-*-aix
3040 i386 running Mach 3.0 i[3456]86-*-mach3*
3041 i386 running Mach i[3456]86-*-mach*
3042 i386 running OSF/1 i[3456]86-*osf1mk*
3043 HP/Apollo 68k Family m68*-apollo*-sysv*,
3045 m68*-hp-bsd*, m68*-hp-hpux*
3046 Argonaut Risc Chip (ARC) arc-*-*
3047 Mitsubishi D30V d30v-*-*
3048 Fujitsu FR30 fr30-*-elf*
3049 OS/9000 i[34]86-*-os9k
3050 I960 with MON960 i960-*-coff
3052 * MIPS $fp behavior changed
3054 The convenience variable $fp, for the MIPS, now consistently returns
3055 the address of the current frame's base. Previously, depending on the
3056 context, $fp could refer to either $sp or the current frame's base
3057 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3058 The GNU Source-Level Debugger''.
3060 *** Changes in GDB 5.3:
3062 * GNU/Linux shared library multi-threaded performance improved.
3064 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3065 `/proc', in preference to `ptrace' for memory reads. This may result
3066 in an improvement in the start-up time of multi-threaded, shared
3067 library applications when run under GDB. One GDB user writes: ``loads
3068 shared libs like mad''.
3070 * ``gdbserver'' now supports multi-threaded applications on some targets
3072 Support for debugging multi-threaded applications which use
3073 the GNU/Linux LinuxThreads package has been added for
3074 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3075 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3077 * GDB now supports C/C++ preprocessor macros.
3079 GDB now expands preprocessor macro invocations in C/C++ expressions,
3080 and provides various commands for showing macro definitions and how
3083 The new command `macro expand EXPRESSION' expands any macro
3084 invocations in expression, and shows the result.
3086 The new command `show macro MACRO-NAME' shows the definition of the
3087 macro named MACRO-NAME, and where it was defined.
3089 Most compilers don't include information about macros in the debugging
3090 information by default. In GCC 3.1, for example, you need to compile
3091 your program with the options `-gdwarf-2 -g3'. If the macro
3092 information is present in the executable, GDB will read it.
3094 * Multi-arched targets.
3096 DEC Alpha (partial) alpha*-*-*
3097 DEC VAX (partial) vax-*-*
3099 National Semiconductor NS32000 (partial) ns32k-*-*
3100 Motorola 68000 (partial) m68k-*-*
3101 Motorola MCORE mcore-*-*
3105 Fujitsu FRV architecture added by Red Hat frv*-*-*
3108 * New native configurations
3110 Alpha NetBSD alpha*-*-netbsd*
3111 SH NetBSD sh*-*-netbsdelf*
3112 MIPS NetBSD mips*-*-netbsd*
3113 UltraSPARC NetBSD sparc64-*-netbsd*
3115 * OBSOLETE configurations and files
3117 Configurations that have been declared obsolete in this release have
3118 been commented out. Unless there is activity to revive these
3119 configurations, the next release of GDB will have their sources
3120 permanently REMOVED.
3122 Mitsubishi D30V d30v-*-*
3123 OS/9000 i[34]86-*-os9k
3124 IBM AIX PS/2 i[3456]86-*-aix
3125 Fujitsu FR30 fr30-*-elf*
3126 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3127 Argonaut Risc Chip (ARC) arc-*-*
3128 i386 running Mach 3.0 i[3456]86-*-mach3*
3129 i386 running Mach i[3456]86-*-mach*
3130 i386 running OSF/1 i[3456]86-*osf1mk*
3131 HP/Apollo 68k Family m68*-apollo*-sysv*,
3133 m68*-hp-bsd*, m68*-hp-hpux*
3134 I960 with MON960 i960-*-coff
3136 * OBSOLETE languages
3138 CHILL, a Pascal like language used by telecommunications companies.
3140 * REMOVED configurations and files
3142 AMD 29k family via UDI a29k-amd-udi, udi29k
3143 A29K VxWorks a29k-*-vxworks
3144 AMD 29000 embedded, using EBMON a29k-none-none
3145 AMD 29000 embedded with COFF a29k-none-coff
3146 AMD 29000 embedded with a.out a29k-none-aout
3148 testsuite/gdb.hp/gdb.threads-hp/ directory
3150 * New command "set max-user-call-depth <nnn>"
3152 This command allows the user to limit the call depth of user-defined
3153 commands. The default is 1024.
3155 * Changes in FreeBSD/i386 native debugging.
3157 Support for the "generate-core-file" has been added.
3159 * New commands "dump", "append", and "restore".
3161 These commands allow data to be copied from target memory
3162 to a bfd-format or binary file (dump and append), and back
3163 from a file into memory (restore).
3165 * Improved "next/step" support on multi-processor Alpha Tru64.
3167 The previous single-step mechanism could cause unpredictable problems,
3168 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3169 of a software single-step mechanism prevents this.
3171 *** Changes in GDB 5.2.1:
3179 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3180 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3181 Fix, by Joel Brobecker imported from mainline.
3183 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3184 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3185 Fix, by Fred Fish, imported from mainline.
3187 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3188 Surprisingly enough, it works now.
3189 By Michal Ludvig, imported from mainline.
3191 i386 hardware watchpoint support:
3192 avoid misses on second run for some targets.
3193 By Pierre Muller, imported from mainline.
3195 *** Changes in GDB 5.2:
3197 * New command "set trust-readonly-sections on[off]".
3199 This command is a hint that tells gdb that read-only sections
3200 really are read-only (ie. that their contents will not change).
3201 In this mode, gdb will go to the object file rather than the
3202 target to read memory from read-only sections (such as ".text").
3203 This can be a significant performance improvement on some
3204 (notably embedded) targets.
3206 * New command "generate-core-file" (or "gcore").
3208 This new gdb command allows the user to drop a core file of the child
3209 process state at any time. So far it's been implemented only for
3210 GNU/Linux and Solaris, but should be relatively easily ported to other
3211 hosts. Argument is core file name (defaults to core.<pid>).
3213 * New command line option
3215 GDB now accepts --pid or -p followed by a process id.
3217 * Change in command line behavior -- corefiles vs. process ids.
3219 There is a subtle behavior in the way in which GDB handles
3220 command line arguments. The first non-flag argument is always
3221 a program to debug, but the second non-flag argument may either
3222 be a corefile or a process id. Previously, GDB would attempt to
3223 open the second argument as a corefile, and if that failed, would
3224 issue a superfluous error message and then attempt to attach it as
3225 a process. Now, if the second argument begins with a non-digit,
3226 it will be treated as a corefile. If it begins with a digit,
3227 GDB will attempt to attach it as a process, and if no such process
3228 is found, will then attempt to open it as a corefile.
3230 * Changes in ARM configurations.
3232 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3233 configuration is fully multi-arch.
3235 * New native configurations
3237 ARM NetBSD arm*-*-netbsd*
3238 x86 OpenBSD i[3456]86-*-openbsd*
3239 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3240 Sparc64 running FreeBSD sparc64-*-freebsd*
3244 Sanyo XStormy16 xstormy16-elf
3246 * OBSOLETE configurations and files
3248 Configurations that have been declared obsolete in this release have
3249 been commented out. Unless there is activity to revive these
3250 configurations, the next release of GDB will have their sources
3251 permanently REMOVED.
3253 AMD 29k family via UDI a29k-amd-udi, udi29k
3254 A29K VxWorks a29k-*-vxworks
3255 AMD 29000 embedded, using EBMON a29k-none-none
3256 AMD 29000 embedded with COFF a29k-none-coff
3257 AMD 29000 embedded with a.out a29k-none-aout
3259 testsuite/gdb.hp/gdb.threads-hp/ directory
3261 * REMOVED configurations and files
3263 TI TMS320C80 tic80-*-*
3265 PowerPC Solaris powerpcle-*-solaris*
3266 PowerPC Windows NT powerpcle-*-cygwin32
3267 PowerPC Netware powerpc-*-netware*
3268 Harris/CXUX m88k m88*-harris-cxux*
3269 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3270 ns32k-utek-sysv* ns32k-utek-*
3271 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3272 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3273 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3274 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3275 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3277 * Changes to command line processing
3279 The new `--args' feature can be used to specify command-line arguments
3280 for the inferior from gdb's command line.
3282 * Changes to key bindings
3284 There is a new `operate-and-get-next' function bound to `C-o'.
3286 *** Changes in GDB 5.1.1
3288 Fix compile problem on DJGPP.
3290 Fix a problem with floating-point registers on the i386 being
3293 Fix to stop GDB crashing on .debug_str debug info.
3295 Numerous documentation fixes.
3297 Numerous testsuite fixes.
3299 *** Changes in GDB 5.1:
3301 * New native configurations
3303 Alpha FreeBSD alpha*-*-freebsd*
3304 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3305 MIPS GNU/Linux mips*-*-linux*
3306 MIPS SGI Irix 6.x mips*-sgi-irix6*
3307 ia64 AIX ia64-*-aix*
3308 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3312 Motorola 68HC11 and 68HC12 m68hc11-elf
3314 UltraSparc running GNU/Linux sparc64-*-linux*
3316 * OBSOLETE configurations and files
3318 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3319 Harris/CXUX m88k m88*-harris-cxux*
3320 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3321 ns32k-utek-sysv* ns32k-utek-*
3322 TI TMS320C80 tic80-*-*
3324 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3325 PowerPC Solaris powerpcle-*-solaris*
3326 PowerPC Windows NT powerpcle-*-cygwin32
3327 PowerPC Netware powerpc-*-netware*
3328 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3329 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3330 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3331 Apple Macintosh (MPW) host N/A
3333 stuff.c (Program to stuff files into a specially prepared space in kdb)
3334 kdb-start.c (Main loop for the standalone kernel debugger)
3336 Configurations that have been declared obsolete in this release have
3337 been commented out. Unless there is activity to revive these
3338 configurations, the next release of GDB will have their sources
3339 permanently REMOVED.
3341 * REMOVED configurations and files
3343 Altos 3068 m68*-altos-*
3344 Convex c1-*-*, c2-*-*
3346 ARM RISCix arm-*-* (as host)
3350 * GDB has been converted to ISO C.
3352 GDB's source code has been converted to ISO C. In particular, the
3353 sources are fully protoized, and rely on standard headers being
3358 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3360 * The MI enabled by default.
3362 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3363 revised and enabled by default. Packages which use GDB as a debugging
3364 engine behind a UI or another front end are encouraged to switch to
3365 using the GDB/MI interface, instead of the old annotations interface
3366 which is now deprecated.
3368 * Support for debugging Pascal programs.
3370 GDB now includes support for debugging Pascal programs. The following
3371 main features are supported:
3373 - Pascal-specific data types such as sets;
3375 - automatic recognition of Pascal sources based on file-name
3378 - Pascal-style display of data types, variables, and functions;
3380 - a Pascal expression parser.
3382 However, some important features are not yet supported.
3384 - Pascal string operations are not supported at all;
3386 - there are some problems with boolean types;
3388 - Pascal type hexadecimal constants are not supported
3389 because they conflict with the internal variables format;
3391 - support for Pascal objects and classes is not full yet;
3393 - unlike Pascal, GDB is case-sensitive for symbol names.
3395 * Changes in completion.
3397 Commands such as `shell', `run' and `set args', which pass arguments
3398 to inferior programs, now complete on file names, similar to what
3399 users expect at the shell prompt.
3401 Commands which accept locations, such as `disassemble', `print',
3402 `breakpoint', `until', etc. now complete on filenames as well as
3403 program symbols. Thus, if you type "break foob TAB", and the source
3404 files linked into the programs include `foobar.c', that file name will
3405 be one of the candidates for completion. However, file names are not
3406 considered for completion after you typed a colon that delimits a file
3407 name from a name of a function in that file, as in "break foo.c:bar".
3409 `set demangle-style' completes on available demangling styles.
3411 * New platform-independent commands:
3413 It is now possible to define a post-hook for a command as well as a
3414 hook that runs before the command. For more details, see the
3415 documentation of `hookpost' in the GDB manual.
3417 * Changes in GNU/Linux native debugging.
3419 Support for debugging multi-threaded programs has been completely
3420 revised for all platforms except m68k and sparc. You can now debug as
3421 many threads as your system allows you to have.
3423 Attach/detach is supported for multi-threaded programs.
3425 Support for SSE registers was added for x86. This doesn't work for
3426 multi-threaded programs though.
3428 * Changes in MIPS configurations.
3430 Multi-arch support is enabled for all MIPS configurations.
3432 GDB can now be built as native debugger on SGI Irix 6.x systems for
3433 debugging n32 executables. (Debugging 64-bit executables is not yet
3436 * Unified support for hardware watchpoints in all x86 configurations.
3438 Most (if not all) native x86 configurations support hardware-assisted
3439 breakpoints and watchpoints in a unified manner. This support
3440 implements debug register sharing between watchpoints, which allows to
3441 put a virtually infinite number of watchpoints on the same address,
3442 and also supports watching regions up to 16 bytes with several debug
3445 The new maintenance command `maintenance show-debug-regs' toggles
3446 debugging print-outs in functions that insert, remove, and test
3447 watchpoints and hardware breakpoints.
3449 * Changes in the DJGPP native configuration.
3451 New command ``info dos sysinfo'' displays assorted information about
3452 the CPU, OS, memory, and DPMI server.
3454 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3455 display information about segment descriptors stored in GDT, LDT, and
3458 New commands ``info dos pde'' and ``info dos pte'' display entries
3459 from Page Directory and Page Tables (for now works with CWSDPMI only).
3460 New command ``info dos address-pte'' displays the Page Table entry for
3461 a given linear address.
3463 GDB can now pass command lines longer than 126 characters to the
3464 program being debugged (requires an update to the libdbg.a library
3465 which is part of the DJGPP development kit).
3467 DWARF2 debug info is now supported.
3469 It is now possible to `step' and `next' through calls to `longjmp'.
3471 * Changes in documentation.
3473 All GDB documentation was converted to GFDL, the GNU Free
3474 Documentation License.
3476 Tracepoints-related commands are now fully documented in the GDB
3479 TUI, the Text-mode User Interface, is now documented in the manual.
3481 Tracepoints-related commands are now fully documented in the GDB
3484 The "GDB Internals" manual now has an index. It also includes
3485 documentation of `ui_out' functions, GDB coding standards, x86
3486 hardware watchpoints, and memory region attributes.
3488 * GDB's version number moved to ``version.in''
3490 The Makefile variable VERSION has been replaced by the file
3491 ``version.in''. People creating GDB distributions should update the
3492 contents of this file.
3496 GUD support is now a standard part of the EMACS distribution.
3498 *** Changes in GDB 5.0:
3500 * Improved support for debugging FP programs on x86 targets
3502 Unified and much-improved support for debugging floating-point
3503 programs on all x86 targets. In particular, ``info float'' now
3504 displays the FP registers in the same format on all x86 targets, with
3505 greater level of detail.
3507 * Improvements and bugfixes in hardware-assisted watchpoints
3509 It is now possible to watch array elements, struct members, and
3510 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3511 on x86 targets no longer erroneously trigger when the address is
3514 * Improvements in the native DJGPP version of GDB
3516 The distribution now includes all the scripts and auxiliary files
3517 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3518 machines ``out of the box''.
3520 The DJGPP version can now debug programs that use signals. It is
3521 possible to catch signals that happened in the debuggee, deliver
3522 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3523 would kill the program being debugged.) Programs that hook hardware
3524 interrupts (keyboard, timer, etc.) can also be debugged.
3526 It is now possible to debug DJGPP programs that redirect their
3527 standard handles or switch them to raw (as opposed to cooked) mode, or
3528 even close them. The command ``run < foo > bar'' works as expected,
3529 and ``info terminal'' reports useful information about the debuggee's
3530 terminal, including raw/cooked mode, redirection, etc.
3532 The DJGPP version now uses termios functions for console I/O, which
3533 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3536 DOS-style file names with drive letters are now fully supported by
3539 It is now possible to debug DJGPP programs that switch their working
3540 directory. It is also possible to rerun the debuggee any number of
3541 times without restarting GDB; thus, you can use the same setup,
3542 breakpoints, etc. for many debugging sessions.
3544 * New native configurations
3546 ARM GNU/Linux arm*-*-linux*
3547 PowerPC GNU/Linux powerpc-*-linux*
3551 Motorola MCore mcore-*-*
3552 x86 VxWorks i[3456]86-*-vxworks*
3553 PowerPC VxWorks powerpc-*-vxworks*
3554 TI TMS320C80 tic80-*-*
3556 * OBSOLETE configurations
3558 Altos 3068 m68*-altos-*
3559 Convex c1-*-*, c2-*-*
3561 ARM RISCix arm-*-* (as host)
3564 Configurations that have been declared obsolete will be commented out,
3565 but the code will be left in place. If there is no activity to revive
3566 these configurations before the next release of GDB, the sources will
3567 be permanently REMOVED.
3569 * Gould support removed
3571 Support for the Gould PowerNode and NP1 has been removed.
3573 * New features for SVR4
3575 On SVR4 native platforms (such as Solaris), if you attach to a process
3576 without first loading a symbol file, GDB will now attempt to locate and
3577 load symbols from the running process's executable file.
3579 * Many C++ enhancements
3581 C++ support has been greatly improved. Overload resolution now works properly
3582 in almost all cases. RTTI support is on the way.
3584 * Remote targets can connect to a sub-program
3586 A popen(3) style serial-device has been added. This device starts a
3587 sub-process (such as a stand-alone simulator) and then communicates
3588 with that. The sub-program to run is specified using the syntax
3589 ``|<program> <args>'' vis:
3591 (gdb) set remotedebug 1
3592 (gdb) target extended-remote |mn10300-elf-sim program-args
3594 * MIPS 64 remote protocol
3596 A long standing bug in the mips64 remote protocol where by GDB
3597 expected certain 32 bit registers (ex SR) to be transfered as 32
3598 instead of 64 bits has been fixed.
3600 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3601 added to provide backward compatibility with older versions of GDB.
3603 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3605 The command ``set remotebinarydownload'' command has been replaced by
3606 ``set remote X-packet''. Other commands in ``set remote'' family
3607 include ``set remote P-packet''.
3609 * Breakpoint commands accept ranges.
3611 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3612 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3613 ``tracepoint passcount'' also accepts a range of tracepoints.
3615 * ``apropos'' command added.
3617 The ``apropos'' command searches through command names and
3618 documentation strings, printing out matches, making it much easier to
3619 try to find a command that does what you are looking for.
3623 A new machine oriented interface (MI) has been added to GDB. This
3624 interface is designed for debug environments running GDB as a separate
3625 process. This is part of the long term libGDB project. See the
3626 "GDB/MI" chapter of the GDB manual for further information. It can be
3627 enabled by configuring with:
3629 .../configure --enable-gdbmi
3631 *** Changes in GDB-4.18:
3633 * New native configurations
3635 HP-UX 10.20 hppa*-*-hpux10.20
3636 HP-UX 11.x hppa*-*-hpux11.0*
3637 M68K GNU/Linux m68*-*-linux*
3641 Fujitsu FR30 fr30-*-elf*
3642 Intel StrongARM strongarm-*-*
3643 Mitsubishi D30V d30v-*-*
3645 * OBSOLETE configurations
3647 Gould PowerNode, NP1 np1-*-*, pn-*-*
3649 Configurations that have been declared obsolete will be commented out,
3650 but the code will be left in place. If there is no activity to revive
3651 these configurations before the next release of GDB, the sources will
3652 be permanently REMOVED.
3656 As a compatibility experiment, GDB's source files buildsym.h and
3657 buildsym.c have been converted to pure standard C, no longer
3658 containing any K&R compatibility code. We believe that all systems in
3659 use today either come with a standard C compiler, or have a GCC port
3660 available. If this is not true, please report the affected
3661 configuration to bug-gdb@gnu.org immediately. See the README file for
3662 information about getting a standard C compiler if you don't have one
3667 GDB now uses readline 2.2.
3669 * set extension-language
3671 You can now control the mapping between filename extensions and source
3672 languages by using the `set extension-language' command. For instance,
3673 you can ask GDB to treat .c files as C++ by saying
3674 set extension-language .c c++
3675 The command `info extensions' lists all of the recognized extensions
3676 and their associated languages.
3678 * Setting processor type for PowerPC and RS/6000
3680 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3681 you can use the `set processor' command to specify what variant of the
3682 PowerPC family you are debugging. The command
3686 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3687 following PowerPC and RS6000 variants:
3689 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3690 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3692 403GC IBM PowerPC 403GC
3693 505 Motorola PowerPC 505
3694 860 Motorola PowerPC 860 or 850
3695 601 Motorola PowerPC 601
3696 602 Motorola PowerPC 602
3697 603 Motorola/IBM PowerPC 603 or 603e
3698 604 Motorola PowerPC 604 or 604e
3699 750 Motorola/IBM PowerPC 750 or 750
3701 At the moment, this command just tells GDB what to name the
3702 special-purpose processor registers. Since almost all the affected
3703 registers are inaccessible to user-level programs, this command is
3704 only useful for remote debugging in its present form.
3708 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3709 more extensive support for HP-UX. Added features include shared
3710 library support, kernel threads and hardware watchpoints for 11.00,
3711 support for HP's ANSI C and C++ compilers, and a compatibility mode
3712 for xdb and dbx commands.
3716 HP's donation includes the new concept of catchpoints, which is a
3717 generalization of the old catch command. On HP-UX, it is now possible
3718 to catch exec, fork, and vfork, as well as library loading.
3720 This means that the existing catch command has changed; its first
3721 argument now specifies the type of catch to be set up. See the
3722 output of "help catch" for a list of catchpoint types.
3724 * Debugging across forks
3726 On HP-UX, you can choose which process to debug when a fork() happens
3731 HP has donated a curses-based terminal user interface (TUI). To get
3732 it, build with --enable-tui. Although this can be enabled for any
3733 configuration, at present it only works for native HP debugging.
3735 * GDB remote protocol additions
3737 A new protocol packet 'X' that writes binary data is now available.
3738 Default behavior is to try 'X', then drop back to 'M' if the stub
3739 fails to respond. The settable variable `remotebinarydownload'
3740 allows explicit control over the use of 'X'.
3742 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3743 full 64-bit address. The command
3745 set remoteaddresssize 32
3747 can be used to revert to the old behaviour. For existing remote stubs
3748 the change should not be noticed, as the additional address information
3751 In order to assist in debugging stubs, you may use the maintenance
3752 command `packet' to send any text string to the stub. For instance,
3754 maint packet heythere
3756 sends the packet "$heythere#<checksum>". Note that it is very easy to
3757 disrupt a debugging session by sending the wrong packet at the wrong
3760 The compare-sections command allows you to compare section data on the
3761 target to what is in the executable file without uploading or
3762 downloading, by comparing CRC checksums.
3764 * Tracing can collect general expressions
3766 You may now collect general expressions at tracepoints. This requires
3767 further additions to the target-side stub; see tracepoint.c and
3768 doc/agentexpr.texi for further details.
3770 * mask-address variable for Mips
3772 For Mips targets, you may control the zeroing of the upper 32 bits of
3773 a 64-bit address by entering `set mask-address on'. This is mainly
3774 of interest to users of embedded R4xxx and R5xxx processors.
3776 * Higher serial baud rates
3778 GDB's serial code now allows you to specify baud rates 57600, 115200,
3779 230400, and 460800 baud. (Note that your host system may not be able
3780 to achieve all of these rates.)
3784 The i960 configuration now includes an initial implementation of a
3785 builtin simulator, contributed by Jim Wilson.
3788 *** Changes in GDB-4.17:
3790 * New native configurations
3792 Alpha GNU/Linux alpha*-*-linux*
3793 Unixware 2.x i[3456]86-unixware2*
3794 Irix 6.x mips*-sgi-irix6*
3795 PowerPC GNU/Linux powerpc-*-linux*
3796 PowerPC Solaris powerpcle-*-solaris*
3797 Sparc GNU/Linux sparc-*-linux*
3798 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3802 Argonaut Risc Chip (ARC) arc-*-*
3803 Hitachi H8/300S h8300*-*-*
3804 Matsushita MN10200 w/simulator mn10200-*-*
3805 Matsushita MN10300 w/simulator mn10300-*-*
3806 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3807 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3808 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3809 Mitsubishi D10V w/simulator d10v-*-*
3810 Mitsubishi M32R/D w/simulator m32r-*-elf*
3811 Tsqware Sparclet sparclet-*-*
3812 NEC V850 w/simulator v850-*-*
3814 * New debugging protocols
3816 ARM with RDI protocol arm*-*-*
3817 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3818 DDB and LSI variants of PMON protocol mips*-*-*
3819 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3820 PowerPC with SDS protocol powerpc{,le}-*-eabi
3821 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3825 All configurations can now understand and use the DWARF 2 debugging
3826 format. The choice is automatic, if the symbol file contains DWARF 2
3831 GDB now includes basic Java language support. This support is
3832 only useful with Java compilers that produce native machine code.
3834 * solib-absolute-prefix and solib-search-path
3836 For SunOS and SVR4 shared libraries, you may now set the prefix for
3837 loading absolute shared library symbol files, and the search path for
3838 locating non-absolute shared library symbol files.
3840 * Live range splitting
3842 GDB can now effectively debug code for which GCC has performed live
3843 range splitting as part of its optimization. See gdb/doc/LRS for
3844 more details on the expected format of the stabs information.
3848 GDB's support for the GNU Hurd, including thread debugging, has been
3849 updated to work with current versions of the Hurd.
3853 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3854 instruction set. ARM GDB automatically detects when Thumb
3855 instructions are in use, and adjusts disassembly and backtracing
3860 GDB's MIPS target configurations now handle the MIP16 16-bit
3865 GDB now includes support for overlays; if an executable has been
3866 linked such that multiple sections are based at the same address, GDB
3867 will decide which section to use for symbolic info. You can choose to
3868 control the decision manually, using overlay commands, or implement
3869 additional target-side support and use "overlay load-target" to bring
3870 in the overlay mapping. Do "help overlay" for more detail.
3874 The command "info symbol <address>" displays information about
3875 the symbol at the specified address.
3879 The standard remote protocol now includes an extension that allows
3880 asynchronous collection and display of trace data. This requires
3881 extensive support in the target-side debugging stub. Tracing mode
3882 includes a new interaction mode in GDB and new commands: see the
3883 file tracepoint.c for more details.
3887 Configurations for embedded MIPS now include a simulator contributed
3888 by Cygnus Solutions. The simulator supports the instruction sets
3889 of most MIPS variants.
3893 Sparc configurations may now include the ERC32 simulator contributed
3894 by the European Space Agency. The simulator is not built into
3895 Sparc targets by default; configure with --enable-sim to include it.
3899 For target configurations that may include multiple variants of a
3900 basic architecture (such as MIPS and SH), you may now set the
3901 architecture explicitly. "set arch" sets, "info arch" lists
3902 the possible architectures.
3904 *** Changes in GDB-4.16:
3906 * New native configurations
3908 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3909 M68K NetBSD m68k-*-netbsd*
3910 PowerPC AIX 4.x powerpc-*-aix*
3911 PowerPC MacOS powerpc-*-macos*
3912 PowerPC Windows NT powerpcle-*-cygwin32
3913 RS/6000 AIX 4.x rs6000-*-aix4*
3917 ARM with RDP protocol arm-*-*
3918 I960 with MON960 i960-*-coff
3919 MIPS VxWorks mips*-*-vxworks*
3920 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3921 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3923 Matra Sparclet sparclet-*-*
3927 The powerpc-eabi configuration now includes the PSIM simulator,
3928 contributed by Andrew Cagney, with assistance from Mike Meissner.
3929 PSIM is a very elaborate model of the PowerPC, including not only
3930 basic instruction set execution, but also details of execution unit
3931 performance and I/O hardware. See sim/ppc/README for more details.
3935 GDB now works with Solaris 2.5.
3937 * Windows 95/NT native
3939 GDB will now work as a native debugger on Windows 95 and Windows NT.
3940 To build it from source, you must use the "gnu-win32" environment,
3941 which uses a DLL to emulate enough of Unix to run the GNU tools.
3942 Further information, binaries, and sources are available at
3943 ftp.cygnus.com, under pub/gnu-win32.
3945 * dont-repeat command
3947 If a user-defined command includes the command `dont-repeat', then the
3948 command will not be repeated if the user just types return. This is
3949 useful if the command is time-consuming to run, so that accidental
3950 extra keystrokes don't run the same command many times.
3952 * Send break instead of ^C
3954 The standard remote protocol now includes an option to send a break
3955 rather than a ^C to the target in order to interrupt it. By default,
3956 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3958 * Remote protocol timeout
3960 The standard remote protocol includes a new variable `remotetimeout'
3961 that allows you to set the number of seconds before GDB gives up trying
3962 to read from the target. The default value is 2.
3964 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3966 By default GDB will automatically keep track of objects as they are
3967 loaded and unloaded by the dynamic linker. By using the command `set
3968 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3969 when shared library events occur, thus allowing you to set breakpoints
3970 in shared libraries which are explicitly loaded by the inferior.
3972 Note this feature does not work on hpux8. On hpux9 you must link
3973 /usr/lib/end.o into your program. This feature should work
3974 automatically on hpux10.
3976 * Irix 5.x hardware watchpoint support
3978 Irix 5 configurations now support the use of hardware watchpoints.
3980 * Mips protocol "SYN garbage limit"
3982 When debugging a Mips target using the `target mips' protocol, you
3983 may set the number of characters that GDB will ignore by setting
3984 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3985 every character. The default value is 1050.
3987 * Recording and replaying remote debug sessions
3989 If you set `remotelogfile' to the name of a file, gdb will write to it
3990 a recording of a remote debug session. This recording may then be
3991 replayed back to gdb using "gdbreplay". See gdbserver/README for
3992 details. This is useful when you have a problem with GDB while doing
3993 remote debugging; you can make a recording of the session and send it
3994 to someone else, who can then recreate the problem.
3996 * Speedups for remote debugging
3998 GDB includes speedups for downloading and stepping MIPS systems using
3999 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4000 and more efficient S-record downloading.
4002 * Memory use reductions and statistics collection
4004 GDB now uses less memory and reports statistics about memory usage.
4005 Try the `maint print statistics' command, for example.
4007 *** Changes in GDB-4.15:
4009 * Psymtabs for XCOFF
4011 The symbol reader for AIX GDB now uses partial symbol tables. This
4012 can greatly improve startup time, especially for large executables.
4014 * Remote targets use caching
4016 Remote targets now use a data cache to speed up communication with the
4017 remote side. The data cache could lead to incorrect results because
4018 it doesn't know about volatile variables, thus making it impossible to
4019 debug targets which use memory mapped I/O devices. `set remotecache
4020 off' turns the the data cache off.
4022 * Remote targets may have threads
4024 The standard remote protocol now includes support for multiple threads
4025 in the target system, using new protocol commands 'H' and 'T'. See
4026 gdb/remote.c for details.
4030 If GDB is configured with `--enable-netrom', then it will include
4031 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4032 acts as though it is a bank of ROM on the target board, but you can
4033 write into it over the network. GDB's support consists only of
4034 support for fast loading into the emulated ROM; to debug, you must use
4035 another protocol, such as standard remote protocol. The usual
4036 sequence is something like
4038 target nrom <netrom-hostname>
4040 target remote <netrom-hostname>:1235
4044 GDB now includes support for the Apple Macintosh, as a host only. It
4045 may be run as either an MPW tool or as a standalone application, and
4046 it can debug through the serial port. All the usual GDB commands are
4047 available, but to the target command, you must supply "serial" as the
4048 device type instead of "/dev/ttyXX". See mpw-README in the main
4049 directory for more information on how to build. The MPW configuration
4050 scripts */mpw-config.in support only a few targets, and only the
4051 mips-idt-ecoff target has been tested.
4055 GDB configuration now uses autoconf. This is not user-visible,
4056 but does simplify configuration and building.
4060 GDB now supports hpux10.
4062 *** Changes in GDB-4.14:
4064 * New native configurations
4066 x86 FreeBSD i[345]86-*-freebsd
4067 x86 NetBSD i[345]86-*-netbsd
4068 NS32k NetBSD ns32k-*-netbsd
4069 Sparc NetBSD sparc-*-netbsd
4073 A29K VxWorks a29k-*-vxworks
4074 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4075 CPU32 EST-300 emulator m68*-*-est*
4076 PowerPC ELF powerpc-*-elf
4079 * Alpha OSF/1 support for procfs
4081 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4082 possible to attach to running processes. As the mounting of the /proc
4083 filesystem is optional on the Alpha, GDB automatically determines
4084 the availability of /proc during startup. This can lead to problems
4085 if /proc is unmounted after GDB has been started.
4087 * Arguments to user-defined commands
4089 User commands may accept up to 10 arguments separated by whitespace.
4090 Arguments are accessed within the user command via $arg0..$arg9. A
4093 print $arg0 + $arg1 + $arg2
4095 To execute the command use:
4098 Defines the command "adder" which prints the sum of its three arguments.
4099 Note the arguments are text substitutions, so they may reference variables,
4100 use complex expressions, or even perform inferior function calls.
4102 * New `if' and `while' commands
4104 This makes it possible to write more sophisticated user-defined
4105 commands. Both commands take a single argument, which is the
4106 expression to evaluate, and must be followed by the commands to
4107 execute, one per line, if the expression is nonzero, the list being
4108 terminated by the word `end'. The `if' command list may include an
4109 `else' word, which causes the following commands to be executed only
4110 if the expression is zero.
4112 * Fortran source language mode
4114 GDB now includes partial support for Fortran 77. It will recognize
4115 Fortran programs and can evaluate a subset of Fortran expressions, but
4116 variables and functions may not be handled correctly. GDB will work
4117 with G77, but does not yet know much about symbols emitted by other
4120 * Better HPUX support
4122 Most debugging facilities now work on dynamic executables for HPPAs
4123 running hpux9 or later. You can attach to running dynamically linked
4124 processes, but by default the dynamic libraries will be read-only, so
4125 for instance you won't be able to put breakpoints in them. To change
4126 that behavior do the following before running the program:
4132 This will cause the libraries to be mapped private and read-write.
4133 To revert to the normal behavior, do this:
4139 You cannot set breakpoints or examine data in the library until after
4140 the library is loaded if the function/data symbols do not have
4143 GDB can now also read debug symbols produced by the HP C compiler on
4144 HPPAs (sorry, no C++, Fortran or 68k support).
4146 * Target byte order now dynamically selectable
4148 You can choose which byte order to use with a target system, via the
4149 commands "set endian big" and "set endian little", and you can see the
4150 current setting by using "show endian". You can also give the command
4151 "set endian auto", in which case GDB will use the byte order
4152 associated with the executable. Currently, only embedded MIPS
4153 configurations support dynamic selection of target byte order.
4155 * New DOS host serial code
4157 This version uses DPMI interrupts to handle buffered I/O, so you
4158 no longer need to run asynctsr when debugging boards connected to
4161 *** Changes in GDB-4.13:
4163 * New "complete" command
4165 This lists all the possible completions for the rest of the line, if it
4166 were to be given as a command itself. This is intended for use by emacs.
4168 * Trailing space optional in prompt
4170 "set prompt" no longer adds a space for you after the prompt you set. This
4171 allows you to set a prompt which ends in a space or one that does not.
4173 * Breakpoint hit counts
4175 "info break" now displays a count of the number of times the breakpoint
4176 has been hit. This is especially useful in conjunction with "ignore"; you
4177 can ignore a large number of breakpoint hits, look at the breakpoint info
4178 to see how many times the breakpoint was hit, then run again, ignoring one
4179 less than that number, and this will get you quickly to the last hit of
4182 * Ability to stop printing at NULL character
4184 "set print null-stop" will cause GDB to stop printing the characters of
4185 an array when the first NULL is encountered. This is useful when large
4186 arrays actually contain only short strings.
4188 * Shared library breakpoints
4190 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4191 breakpoints in shared libraries before the executable is run.
4193 * Hardware watchpoints
4195 There is a new hardware breakpoint for the watch command for sparclite
4196 targets. See gdb/sparclite/hw_breakpoint.note.
4198 Hardware watchpoints are also now supported under GNU/Linux.
4202 Annotations have been added. These are for use with graphical interfaces,
4203 and are still experimental. Currently only gdba.el uses these.
4205 * Improved Irix 5 support
4207 GDB now works properly with Irix 5.2.
4209 * Improved HPPA support
4211 GDB now works properly with the latest GCC and GAS.
4213 * New native configurations
4215 Sequent PTX4 i[34]86-sequent-ptx4
4216 HPPA running OSF/1 hppa*-*-osf*
4217 Atari TT running SVR4 m68*-*-sysv4*
4218 RS/6000 LynxOS rs6000-*-lynxos*
4222 OS/9000 i[34]86-*-os9k
4223 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4226 * Hitachi SH7000 and E7000-PC ICE support
4228 There is now support for communicating with the Hitachi E7000-PC ICE.
4229 This is available automatically when GDB is configured for the SH.
4233 As usual, a variety of small fixes and improvements, both generic
4234 and configuration-specific. See the ChangeLog for more detail.
4236 *** Changes in GDB-4.12:
4238 * Irix 5 is now supported
4242 GDB-4.12 on the HPPA has a number of changes which make it unable
4243 to debug the output from the currently released versions of GCC and
4244 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4245 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4246 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4249 *** Changes in GDB-4.11:
4251 * User visible changes:
4255 The "set remotedebug" option is now consistent between the mips remote
4256 target, remote targets using the gdb-specific protocol, UDI (AMD's
4257 debug protocol for the 29k) and the 88k bug monitor. It is now an
4258 integer specifying a debug level (normally 0 or 1, but 2 means more
4259 debugging info for the mips target).
4261 * DEC Alpha native support
4263 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4264 debug info, but GDB works fairly well with the DEC compiler and should
4265 work with a future GCC release. See the README file for a few
4266 Alpha-specific notes.
4268 * Preliminary thread implementation
4270 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4272 * LynxOS native and target support for 386
4274 This release has been hosted on LynxOS 2.2, and also can be configured
4275 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4278 * Improvements in C++ mangling/demangling.
4280 This release has much better g++ debugging, specifically in name
4281 mangling/demangling, virtual function calls, print virtual table,
4282 call methods, ...etc.
4284 *** Changes in GDB-4.10:
4286 * User visible changes:
4288 Remote debugging using the GDB-specific (`target remote') protocol now
4289 supports the `load' command. This is only useful if you have some
4290 other way of getting the stub to the target system, and you can put it
4291 somewhere in memory where it won't get clobbered by the download.
4293 Filename completion now works.
4295 When run under emacs mode, the "info line" command now causes the
4296 arrow to point to the line specified. Also, "info line" prints
4297 addresses in symbolic form (as well as hex).
4299 All vxworks based targets now support a user settable option, called
4300 vxworks-timeout. This option represents the number of seconds gdb
4301 should wait for responses to rpc's. You might want to use this if
4302 your vxworks target is, perhaps, a slow software simulator or happens
4303 to be on the far side of a thin network line.
4307 This release contains support for using a DEC alpha as a GDB host for
4308 cross debugging. Native alpha debugging is not supported yet.
4311 *** Changes in GDB-4.9:
4315 This is the first GDB release which is accompanied by a matching testsuite.
4316 The testsuite requires installation of dejagnu, which should be available
4317 via ftp from most sites that carry GNU software.
4321 'Cfront' style demangling has had its name changed to 'ARM' style, to
4322 emphasize that it was written from the specifications in the C++ Annotated
4323 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4324 disclaimers, it still generated too much confusion with users attempting to
4325 use gdb with AT&T cfront.
4329 GDB now uses a standard remote interface to a simulator library.
4330 So far, the library contains simulators for the Zilog Z8001/2, the
4331 Hitachi H8/300, H8/500 and Super-H.
4333 * New targets supported
4335 H8/300 simulator h8300-hitachi-hms or h8300hms
4336 H8/500 simulator h8500-hitachi-hms or h8500hms
4337 SH simulator sh-hitachi-hms or sh
4338 Z8000 simulator z8k-zilog-none or z8ksim
4339 IDT MIPS board over serial line mips-idt-ecoff
4341 Cross-debugging to GO32 targets is supported. It requires a custom
4342 version of the i386-stub.c module which is integrated with the
4343 GO32 memory extender.
4345 * New remote protocols
4347 MIPS remote debugging protocol.
4349 * New source languages supported
4351 This version includes preliminary support for Chill, a Pascal like language
4352 used by telecommunications companies. Chill support is also being integrated
4353 into the GNU compiler, but we don't know when it will be publically available.
4356 *** Changes in GDB-4.8:
4358 * HP Precision Architecture supported
4360 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4361 version of this support was available as a set of patches from the
4362 University of Utah. GDB does not support debugging of programs
4363 compiled with the HP compiler, because HP will not document their file
4364 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4365 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4367 Many problems in the preliminary version have been fixed.
4369 * Faster and better demangling
4371 We have improved template demangling and fixed numerous bugs in the GNU style
4372 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4373 character types (wchar_t) are now supported. Demangling of each symbol is now
4374 only done once, and is cached when the symbol table for a file is read in.
4375 This results in a small increase in memory usage for C programs, a moderate
4376 increase in memory usage for C++ programs, and a fantastic speedup in
4379 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4380 from the specifications in the Annotated Reference Manual, which AT&T's
4381 compiler does not actually implement.
4383 * G++ multiple inheritance compiler problem
4385 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4386 inheritance lattices was reworked to properly discover ambiguities. We
4387 recently found an example which causes this new algorithm to fail in a
4388 very subtle way, producing bad debug information for those classes.
4389 The file 'gcc.patch' (in this directory) can be applied to gcc to
4390 circumvent the problem. A future GCC release will contain a complete
4393 The previous G++ debug info problem (mentioned below for the gdb-4.7
4394 release) is fixed in gcc version 2.3.2.
4396 * Improved configure script
4398 The `configure' script will now attempt to guess your system type if
4399 you don't supply a host system type. The old scheme of supplying a
4400 host system triplet is preferable over using this. All the magic is
4401 done in the new `config.guess' script. Examine it for details.
4403 We have also brought our configure script much more in line with the FSF's
4404 version. It now supports the --with-xxx options. In particular,
4405 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4406 The resulting GDB will not be able to read arbitrary object file formats --
4407 only the format ``expected'' to be used on the configured target system.
4408 We hope to make this the default in a future release.
4410 * Documentation improvements
4412 There's new internal documentation on how to modify GDB, and how to
4413 produce clean changes to the code. We implore people to read it
4414 before submitting changes.
4416 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4417 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4418 `info' files are also provided. To build `info' files from scratch,
4419 you will need the latest `makeinfo' release, which will be available in
4420 a future texinfo-X.Y release.
4422 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4423 We're not sure exactly which versions have this problem, but it has
4424 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4425 or better. If that isn't possible, there is a patch in
4426 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4427 around this problem.
4431 GDB now supports array constants that can be used in expressions typed in by
4432 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4433 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4436 The new directory `gdb/sparclite' contains a program that demonstrates
4437 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4439 * New native hosts supported
4441 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4442 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4444 * New targets supported
4446 AMD 29k family via UDI a29k-amd-udi or udi29k
4448 * New file formats supported
4450 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4451 HPUX core files, and SCO 3.2v2 core files.
4455 Attaching to processes now works again; thanks for the many bug reports.
4457 We have also stomped on a bunch of core dumps caused by
4458 printf_filtered("%s") problems.
4460 We eliminated a copyright problem on the rpc and ptrace header files
4461 for VxWorks, which was discovered at the last minute during the 4.7
4462 release. You should now be able to build a VxWorks GDB.
4464 You can now interrupt gdb while an attached process is running. This
4465 will cause the attached process to stop, and give control back to GDB.
4467 We fixed problems caused by using too many file descriptors
4468 for reading symbols from object files and libraries. This was
4469 especially a problem for programs that used many (~100) shared
4472 The `step' command now only enters a subroutine if there is line number
4473 information for the subroutine. Otherwise it acts like the `next'
4474 command. Previously, `step' would enter subroutines if there was
4475 any debugging information about the routine. This avoids problems
4476 when using `cc -g1' on MIPS machines.
4478 * Internal improvements
4480 GDB's internal interfaces have been improved to make it easier to support
4481 debugging of multiple languages in the future.
4483 GDB now uses a common structure for symbol information internally.
4484 Minimal symbols (derived from linkage symbols in object files), partial
4485 symbols (from a quick scan of debug information), and full symbols
4486 contain a common subset of information, making it easier to write
4487 shared code that handles any of them.
4489 * New command line options
4491 We now accept --silent as an alias for --quiet.
4495 The memory-mapped-malloc library is now licensed under the GNU Library
4496 General Public License.
4498 *** Changes in GDB-4.7:
4500 * Host/native/target split
4502 GDB has had some major internal surgery to untangle the support for
4503 hosts and remote targets. Now, when you configure GDB for a remote
4504 target, it will no longer load in all of the support for debugging
4505 local programs on the host. When fully completed and tested, this will
4506 ensure that arbitrary host/target combinations are possible.
4508 The primary conceptual shift is to separate the non-portable code in
4509 GDB into three categories. Host specific code is required any time GDB
4510 is compiled on that host, regardless of the target. Target specific
4511 code relates to the peculiarities of the target, but can be compiled on
4512 any host. Native specific code is everything else: it can only be
4513 built when the host and target are the same system. Child process
4514 handling and core file support are two common `native' examples.
4516 GDB's use of /proc for controlling Unix child processes is now cleaner.
4517 It has been split out into a single module under the `target_ops' vector,
4518 plus two native-dependent functions for each system that uses /proc.
4520 * New hosts supported
4522 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4523 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4524 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4526 * New targets supported
4528 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4529 68030 and CPU32 m68030-*-*, m68332-*-*
4531 * New native hosts supported
4533 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4534 (386bsd is not well tested yet)
4535 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4537 * New file formats supported
4539 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4540 supports reading of `a.out.adobe' object files, which are an a.out
4541 format extended with minimal information about multiple sections.
4545 `show copying' is the same as the old `info copying'.
4546 `show warranty' is the same as `info warrantee'.
4547 These were renamed for consistency. The old commands continue to work.
4549 `info handle' is a new alias for `info signals'.
4551 You can now define pre-command hooks, which attach arbitrary command
4552 scripts to any command. The commands in the hook will be executed
4553 prior to the user's command. You can also create a hook which will be
4554 executed whenever the program stops. See gdb.texinfo.
4558 We now deal with Cfront style name mangling, and can even extract type
4559 info from mangled symbols. GDB can automatically figure out which
4560 symbol mangling style your C++ compiler uses.
4562 Calling of methods and virtual functions has been improved as well.
4566 The crash that occured when debugging Sun Ansi-C compiled binaries is
4567 fixed. This was due to mishandling of the extra N_SO stabs output
4570 We also finally got Ultrix 4.2 running in house, and fixed core file
4571 support, with help from a dozen people on the net.
4573 John M. Farrell discovered that the reason that single-stepping was so
4574 slow on all of the Mips based platforms (primarily SGI and DEC) was
4575 that we were trying to demangle and lookup a symbol used for internal
4576 purposes on every instruction that was being stepped through. Changing
4577 the name of that symbol so that it couldn't be mistaken for a C++
4578 mangled symbol sped things up a great deal.
4580 Rich Pixley sped up symbol lookups in general by getting much smarter
4581 about when C++ symbol mangling is necessary. This should make symbol
4582 completion (TAB on the command line) much faster. It's not as fast as
4583 we'd like, but it's significantly faster than gdb-4.6.
4587 A new user controllable variable 'call_scratch_address' can
4588 specify the location of a scratch area to be used when GDB
4589 calls a function in the target. This is necessary because the
4590 usual method of putting the scratch area on the stack does not work
4591 in systems that have separate instruction and data spaces.
4593 We integrated changes to support the 29k UDI (Universal Debugger
4594 Interface), but discovered at the last minute that we didn't have all
4595 of the appropriate copyright paperwork. We are working with AMD to
4596 resolve this, and hope to have it available soon.
4600 We have sped up the remote serial line protocol, especially for targets
4601 with lots of registers. It now supports a new `expedited status' ('T')
4602 message which can be used in place of the existing 'S' status message.
4603 This allows the remote stub to send only the registers that GDB
4604 needs to make a quick decision about single-stepping or conditional
4605 breakpoints, eliminating the need to fetch the entire register set for
4606 each instruction being stepped through.
4608 The GDB remote serial protocol now implements a write-through cache for
4609 registers, only re-reading the registers if the target has run.
4611 There is also a new remote serial stub for SPARC processors. You can
4612 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4613 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4614 processor with a serial port.
4618 Configure.in files have become much easier to read and modify. A new
4619 `table driven' format makes it more obvious what configurations are
4620 supported, and what files each one uses.
4624 There is a new opcodes library which will eventually contain all of the
4625 disassembly routines and opcode tables. At present, it only contains
4626 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4627 disassembler (binutils/objdump) to share these routines.
4629 The libiberty library is now copylefted under the GNU Library General
4630 Public License. This allows more liberal use, and was done so libg++
4631 can use it. This makes no difference to GDB, since the Library License
4632 grants all the rights from the General Public License.
4636 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4637 reference to the stabs symbol info used by the debugger. It is (as far
4638 as we know) the only published document on this fascinating topic. We
4639 encourage you to read it, compare it to the stabs information on your
4640 system, and send improvements on the document in general (to
4641 bug-gdb@prep.ai.mit.edu).
4643 And, of course, many bugs have been fixed.
4646 *** Changes in GDB-4.6:
4648 * Better support for C++ function names
4650 GDB now accepts as input the "demangled form" of C++ overloaded function
4651 names and member function names, and can do command completion on such names
4652 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4653 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4654 Make use of command completion, it is your friend.
4656 GDB also now accepts a variety of C++ mangled symbol formats. They are
4657 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4658 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4659 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4660 for the list of formats.
4662 * G++ symbol mangling problem
4664 Recent versions of gcc have a bug in how they emit debugging information for
4665 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4666 directory) can be applied to gcc to fix the problem. Alternatively, if you
4667 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4668 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4669 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4672 * New 'maintenance' command
4674 All of the commands related to hacking GDB internals have been moved out of
4675 the main command set, and now live behind the 'maintenance' command. This
4676 can also be abbreviated as 'mt'. The following changes were made:
4678 dump-me -> maintenance dump-me
4679 info all-breakpoints -> maintenance info breakpoints
4680 printmsyms -> maintenance print msyms
4681 printobjfiles -> maintenance print objfiles
4682 printpsyms -> maintenance print psymbols
4683 printsyms -> maintenance print symbols
4685 The following commands are new:
4687 maintenance demangle Call internal GDB demangler routine to
4688 demangle a C++ link name and prints the result.
4689 maintenance print type Print a type chain for a given symbol
4691 * Change to .gdbinit file processing
4693 We now read the $HOME/.gdbinit file before processing the argv arguments
4694 (e.g. reading symbol files or core files). This allows global parameters to
4695 be set, which will apply during the symbol reading. The ./.gdbinit is still
4696 read after argv processing.
4698 * New hosts supported
4700 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4702 GNU/Linux support i386-unknown-linux or linux
4704 We are also including code to support the HP/PA running BSD and HPUX. This
4705 is almost guaranteed not to work, as we didn't have time to test or build it
4706 for this release. We are including it so that the more adventurous (or
4707 masochistic) of you can play with it. We also had major problems with the
4708 fact that the compiler that we got from HP doesn't support the -g option.
4711 * New targets supported
4713 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4715 * More smarts about finding #include files
4717 GDB now remembers the compilation directory for all include files, and for
4718 all files from which C is generated (like yacc and lex sources). This
4719 greatly improves GDB's ability to find yacc/lex sources, and include files,
4720 especially if you are debugging your program from a directory different from
4721 the one that contains your sources.
4723 We also fixed a bug which caused difficulty with listing and setting
4724 breakpoints in include files which contain C code. (In the past, you had to
4725 try twice in order to list an include file that you hadn't looked at before.)
4727 * Interesting infernals change
4729 GDB now deals with arbitrary numbers of sections, where the symbols for each
4730 section must be relocated relative to that section's landing place in the
4731 target's address space. This work was needed to support ELF with embedded
4732 stabs used by Solaris-2.0.
4734 * Bug fixes (of course!)
4736 There have been loads of fixes for the following things:
4737 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4738 i960, stabs, DOS(GO32), procfs, etc...
4740 See the ChangeLog for details.
4742 *** Changes in GDB-4.5:
4744 * New machines supported (host and target)
4746 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4748 SGI Irix-4.x mips-sgi-irix4 or iris4
4750 * New malloc package
4752 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4753 Mmalloc is capable of handling mutiple heaps of memory. It is also
4754 capable of saving a heap to a file, and then mapping it back in later.
4755 This can be used to greatly speedup the startup of GDB by using a
4756 pre-parsed symbol table which lives in a mmalloc managed heap. For
4757 more details, please read mmalloc/mmalloc.texi.
4761 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4762 'help info proc' for details.
4764 * MIPS ecoff symbol table format
4766 The code that reads MIPS symbol table format is now supported on all hosts.
4767 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4770 * File name changes for MS-DOS
4772 Many files in the config directories have been renamed to make it easier to
4773 support GDB on MS-DOSe systems (which have very restrictive file name
4774 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4775 environment) is close to working but has some remaining problems. Note
4776 that debugging of DOS programs is not supported, due to limitations
4777 in the ``operating system'', but it can be used to host cross-debugging.
4779 * Cross byte order fixes
4781 Many fixes have been made to support cross debugging of Sparc and MIPS
4782 targets from hosts whose byte order differs.
4784 * New -mapped and -readnow options
4786 If memory-mapped files are available on your system through the 'mmap'
4787 system call, you can use the -mapped option on the `file' or
4788 `symbol-file' commands to cause GDB to write the symbols from your
4789 program into a reusable file. If the program you are debugging is
4790 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4791 Future GDB debugging sessions will notice the presence of this file,
4792 and will quickly map in symbol information from it, rather than reading
4793 the symbol table from the executable program. Using the '-mapped'
4794 option in a GDB `file' or `symbol-file' command has the same effect as
4795 starting GDB with the '-mapped' command-line option.
4797 You can cause GDB to read the entire symbol table immediately by using
4798 the '-readnow' option with any of the commands that load symbol table
4799 information (or on the GDB command line). This makes the command
4800 slower, but makes future operations faster.
4802 The -mapped and -readnow options are typically combined in order to
4803 build a `fred.syms' file that contains complete symbol information.
4804 A simple GDB invocation to do nothing but build a `.syms' file for future
4807 gdb -batch -nx -mapped -readnow programname
4809 The `.syms' file is specific to the host machine on which GDB is run.
4810 It holds an exact image of GDB's internal symbol table. It cannot be
4811 shared across multiple host platforms.
4813 * longjmp() handling
4815 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4816 siglongjmp() without losing control. This feature has not yet been ported to
4817 all systems. It currently works on many 386 platforms, all MIPS-based
4818 platforms (SGI, DECstation, etc), and Sun3/4.
4822 Preliminary work has been put in to support the new Solaris OS from Sun. At
4823 this time, it can control and debug processes, but it is not capable of
4828 As always, many many bug fixes. The major areas were with g++, and mipsread.
4829 People using the MIPS-based platforms should experience fewer mysterious
4830 crashes and trashed symbol tables.
4832 *** Changes in GDB-4.4:
4834 * New machines supported (host and target)
4836 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4838 BSD Reno on Vax vax-dec-bsd
4839 Ultrix on Vax vax-dec-ultrix
4841 * New machines supported (target)
4843 AMD 29000 embedded, using EBMON a29k-none-none
4847 GDB continues to improve its handling of C++. `References' work better.
4848 The demangler has also been improved, and now deals with symbols mangled as
4849 per the Annotated C++ Reference Guide.
4851 GDB also now handles `stabs' symbol information embedded in MIPS
4852 `ecoff' symbol tables. Since the ecoff format was not easily
4853 extensible to handle new languages such as C++, this appeared to be a
4854 good way to put C++ debugging info into MIPS binaries. This option
4855 will be supported in the GNU C compiler, version 2, when it is
4858 * New features for SVR4
4860 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4861 shared libraries. Debugging dynamically linked programs should present
4862 only minor differences from debugging statically linked programs.
4864 The `info proc' command will print out information about any process
4865 on an SVR4 system (including the one you are debugging). At the moment,
4866 it prints the address mappings of the process.
4868 If you bring up GDB on another SVR4 system, please send mail to
4869 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4871 * Better dynamic linking support in SunOS
4873 Reading symbols from shared libraries which contain debugging symbols
4874 now works properly. However, there remain issues such as automatic
4875 skipping of `transfer vector' code during function calls, which
4876 make it harder to debug code in a shared library, than to debug the
4877 same code linked statically.
4881 GDB is now using the latest `getopt' routines from the FSF. This
4882 version accepts the -- prefix for options with long names. GDB will
4883 continue to accept the old forms (-option and +option) as well.
4884 Various single letter abbreviations for options have been explicity
4885 added to the option table so that they won't get overshadowed in the
4886 future by other options that begin with the same letter.
4890 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4891 Many assorted bugs have been handled. Many more remain to be handled.
4892 See the various ChangeLog files (primarily in gdb and bfd) for details.
4895 *** Changes in GDB-4.3:
4897 * New machines supported (host and target)
4899 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4900 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4901 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4903 * Almost SCO Unix support
4905 We had hoped to support:
4906 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4907 (except for core file support), but we discovered very late in the release
4908 that it has problems with process groups that render gdb unusable. Sorry
4909 about that. I encourage people to fix it and post the fixes.
4911 * Preliminary ELF and DWARF support
4913 GDB can read ELF object files on System V Release 4, and can handle
4914 debugging records for C, in DWARF format, in ELF files. This support
4915 is preliminary. If you bring up GDB on another SVR4 system, please
4916 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4921 GDB now uses the latest `readline' library. One user-visible change
4922 is that two tabs will list possible command completions, which previously
4923 required typing M-? (meta-question mark, or ESC ?).
4927 The `stepi' bug that many of you noticed has been squashed.
4928 Many bugs in C++ have been handled. Many more remain to be handled.
4929 See the various ChangeLog files (primarily in gdb and bfd) for details.
4931 * State of the MIPS world (in case you wondered):
4933 GDB can understand the symbol tables emitted by the compilers
4934 supplied by most vendors of MIPS-based machines, including DEC. These
4935 symbol tables are in a format that essentially nobody else uses.
4937 Some versions of gcc come with an assembler post-processor called
4938 mips-tfile. This program is required if you want to do source-level
4939 debugging of gcc-compiled programs. I believe FSF does not ship
4940 mips-tfile with gcc version 1, but it will eventually come with gcc
4943 Debugging of g++ output remains a problem. g++ version 1.xx does not
4944 really support it at all. (If you're lucky, you should be able to get
4945 line numbers and stack traces to work, but no parameters or local
4946 variables.) With some work it should be possible to improve the
4949 When gcc version 2 is released, you will have somewhat better luck.
4950 However, even then you will get confusing results for inheritance and
4953 We will eventually provide full debugging of g++ output on
4954 DECstations. This will probably involve some kind of stabs-in-ecoff
4955 encapulation, but the details have not been worked out yet.
4958 *** Changes in GDB-4.2:
4960 * Improved configuration
4962 Only one copy of `configure' exists now, and it is not self-modifying.
4963 Porting BFD is simpler.
4967 The `step' and `next' commands now only stop at the first instruction
4968 of a source line. This prevents the multiple stops that used to occur
4969 in switch statements, for-loops, etc. `Step' continues to stop if a
4970 function that has debugging information is called within the line.
4974 Lots of small bugs fixed. More remain.
4976 * New host supported (not target)
4978 Intel 386 PC clone running Mach i386-none-mach
4981 *** Changes in GDB-4.1:
4983 * Multiple source language support
4985 GDB now has internal scaffolding to handle several source languages.
4986 It determines the type of each source file from its filename extension,
4987 and will switch expression parsing and number formatting to match the
4988 language of the function in the currently selected stack frame.
4989 You can also specifically set the language to be used, with
4990 `set language c' or `set language modula-2'.
4994 GDB now has preliminary support for the GNU Modula-2 compiler,
4995 currently under development at the State University of New York at
4996 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4997 continue through the fall of 1991 and into 1992.
4999 Other Modula-2 compilers are currently not supported, and attempting to
5000 debug programs compiled with them will likely result in an error as the
5001 symbol table is read. Feel free to work on it, though!
5003 There are hooks in GDB for strict type checking and range checking,
5004 in the `Modula-2 philosophy', but they do not currently work.
5008 GDB can now write to executable and core files (e.g. patch
5009 a variable's value). You must turn this switch on, specify
5010 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5011 by assigning a new value to a variable. Modifications take
5014 * Automatic SunOS shared library reading
5016 When you run your program, GDB automatically determines where its
5017 shared libraries (if any) have been loaded, and reads their symbols.
5018 The `share' command is no longer needed. This also works when
5019 examining core files.
5023 You can specify the number of lines that the `list' command shows.
5026 * New machines supported (host and target)
5028 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5029 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5030 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5032 * New hosts supported (not targets)
5034 IBM RT/PC: romp-ibm-aix or rtpc
5036 * New targets supported (not hosts)
5038 AMD 29000 embedded with COFF a29k-none-coff
5039 AMD 29000 embedded with a.out a29k-none-aout
5040 Ultracomputer remote kernel debug a29k-nyu-kern
5042 * New remote interfaces
5048 *** Changes in GDB-4.0:
5052 Wide output is wrapped at good places to make the output more readable.
5054 Gdb now supports cross-debugging from a host machine of one type to a
5055 target machine of another type. Communication with the target system
5056 is over serial lines. The ``target'' command handles connecting to the
5057 remote system; the ``load'' command will download a program into the
5058 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5059 also supports debugging of realtime processes running under VxWorks,
5060 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5061 stub on the target system.
5063 New CPUs supported include the AMD 29000 and Intel 960.
5065 GDB now reads object files and symbol tables via a ``binary file''
5066 library, which allows a single copy of GDB to debug programs of multiple
5067 object file types such as a.out and coff.
5069 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5070 refcard.dvi and refcard.ps are available to format it).
5073 * Control-Variable user interface simplified
5075 All variables that control the operation of the debugger can be set
5076 by the ``set'' command, and displayed by the ``show'' command.
5078 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5079 ``Show prompt'' produces the response:
5080 Gdb's prompt is new-gdb=>.
5082 What follows are the NEW set commands. The command ``help set'' will
5083 print a complete list of old and new set commands. ``help set FOO''
5084 will give a longer description of the variable FOO. ``show'' will show
5085 all of the variable descriptions and their current settings.
5087 confirm on/off: Enables warning questions for operations that are
5088 hard to recover from, e.g. rerunning the program while
5089 it is already running. Default is ON.
5091 editing on/off: Enables EMACS style command line editing
5092 of input. Previous lines can be recalled with
5093 control-P, the current line can be edited with control-B,
5094 you can search for commands with control-R, etc.
5097 history filename NAME: NAME is where the gdb command history
5098 will be stored. The default is .gdb_history,
5099 or the value of the environment variable
5102 history size N: The size, in commands, of the command history. The
5103 default is 256, or the value of the environment variable
5106 history save on/off: If this value is set to ON, the history file will
5107 be saved after exiting gdb. If set to OFF, the
5108 file will not be saved. The default is OFF.
5110 history expansion on/off: If this value is set to ON, then csh-like
5111 history expansion will be performed on
5112 command line input. The default is OFF.
5114 radix N: Sets the default radix for input and output. It can be set
5115 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5116 in the current radix, so "set radix 10" is always a no-op.
5118 height N: This integer value is the number of lines on a page. Default
5119 is 24, the current `stty rows'' setting, or the ``li#''
5120 setting from the termcap entry matching the environment
5123 width N: This integer value is the number of characters on a line.
5124 Default is 80, the current `stty cols'' setting, or the ``co#''
5125 setting from the termcap entry matching the environment
5128 Note: ``set screensize'' is obsolete. Use ``set height'' and
5129 ``set width'' instead.
5131 print address on/off: Print memory addresses in various command displays,
5132 such as stack traces and structure values. Gdb looks
5133 more ``symbolic'' if you turn this off; it looks more
5134 ``machine level'' with it on. Default is ON.
5136 print array on/off: Prettyprint arrays. New convenient format! Default
5139 print demangle on/off: Print C++ symbols in "source" form if on,
5142 print asm-demangle on/off: Same, for assembler level printouts
5145 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5148 * Support for Epoch Environment.
5150 The epoch environment is a version of Emacs v18 with windowing. One
5151 new command, ``inspect'', is identical to ``print'', except that if you
5152 are running in the epoch environment, the value is printed in its own
5156 * Support for Shared Libraries
5158 GDB can now debug programs and core files that use SunOS shared libraries.
5159 Symbols from a shared library cannot be referenced
5160 before the shared library has been linked with the program (this
5161 happens after you type ``run'' and before the function main() is entered).
5162 At any time after this linking (including when examining core files
5163 from dynamically linked programs), gdb reads the symbols from each
5164 shared library when you type the ``sharedlibrary'' command.
5165 It can be abbreviated ``share''.
5167 sharedlibrary REGEXP: Load shared object library symbols for files
5168 matching a unix regular expression. No argument
5169 indicates to load symbols for all shared libraries.
5171 info sharedlibrary: Status of loaded shared libraries.
5176 A watchpoint stops execution of a program whenever the value of an
5177 expression changes. Checking for this slows down execution
5178 tremendously whenever you are in the scope of the expression, but is
5179 quite useful for catching tough ``bit-spreader'' or pointer misuse
5180 problems. Some machines such as the 386 have hardware for doing this
5181 more quickly, and future versions of gdb will use this hardware.
5183 watch EXP: Set a watchpoint (breakpoint) for an expression.
5185 info watchpoints: Information about your watchpoints.
5187 delete N: Deletes watchpoint number N (same as breakpoints).
5188 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5189 enable N: Re-enables watchpoint number N (same as breakpoints).
5192 * C++ multiple inheritance
5194 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5197 * C++ exception handling
5199 Gdb now supports limited C++ exception handling. Besides the existing
5200 ability to breakpoint on an exception handler, gdb can breakpoint on
5201 the raising of an exception (before the stack is peeled back to the
5204 catch FOO: If there is a FOO exception handler in the dynamic scope,
5205 set a breakpoint to catch exceptions which may be raised there.
5206 Multiple exceptions (``catch foo bar baz'') may be caught.
5208 info catch: Lists all exceptions which may be caught in the
5209 current stack frame.
5212 * Minor command changes
5214 The command ``call func (arg, arg, ...)'' now acts like the print
5215 command, except it does not print or save a value if the function's result
5216 is void. This is similar to dbx usage.
5218 The ``up'' and ``down'' commands now always print the frame they end up
5219 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5220 frames without printing.
5222 * New directory command
5224 'dir' now adds directories to the FRONT of the source search path.
5225 The path starts off empty. Source files that contain debug information
5226 about the directory in which they were compiled can be found even
5227 with an empty path; Sun CC and GCC include this information. If GDB can't
5228 find your source file in the current directory, type "dir .".
5230 * Configuring GDB for compilation
5232 For normal use, type ``./configure host''. See README or gdb.texinfo
5235 GDB now handles cross debugging. If you are remotely debugging between
5236 two different machines, type ``./configure host -target=targ''.
5237 Host is the machine where GDB will run; targ is the machine
5238 where the program that you are debugging will run.