1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.5
6 * If the configured location of system.gdbinit file (as given by the
7 --with-system-gdbinit option at configure time) is in the
8 data-directory (as specified by --with-gdb-datadir at configure
9 time) or in one of its subdirectories, then GDB will look for the
10 system-wide init file in the directory specified by the
11 --data-directory command-line option.
13 * New command line options:
15 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
16 other initialization files, unlike -nx which disables all of them.
18 * The 'ptype' and 'whatis' commands now accept an argument to control
23 ** Vectors can be created with gdb.Type.vector.
25 ** Python's atexit.register now works in GDB.
27 ** Types can be pretty-printed via a Python API.
29 * New Python-based convenience functions:
31 ** $_memeq(buf1, buf2, length)
32 ** $_streq(str1, str2)
34 ** $_regex(str, regex)
36 * The 'cd' command now defaults to using '~' (the home directory) if not
39 * The command 'forward-search' can now be abbreviated as 'fo'.
41 * New configure options
43 --enable-libmcheck/--disable-libmcheck
44 By default, development versions are built with -lmcheck on hosts
45 that support it, in order to help track memory corruption issues.
46 Release versions, on the other hand, are built without -lmcheck
47 by default. The --enable-libmcheck/--disable-libmcheck configure
48 options allow the user to override that default.
50 * New commands (for set/show, see "New options" below)
53 List the BFDs known to GDB.
55 python-interactive [command]
57 Start a Python interactive prompt, or evaluate the optional command
58 and print the result of expressions.
61 "py" is a new alias for "python".
63 enable type-printer [name]...
64 disable type-printer [name]...
65 Enable or disable type printers.
69 ** For the Renesas Super-H architecture, the "regs" command has been removed
70 (has been deprecated in GDB 7.5), and "info all-registers" should be used
75 set print type methods (on|off)
76 show print type methods
77 Control whether method declarations are displayed by "ptype".
78 The default is to show them.
80 set print type typedefs (on|off)
81 show print type typedefs
82 Control whether typedef definitions are displayed by "ptype".
83 The default is to show them.
87 ** Command parameter changes are now notified using new async record
89 ** Trace frame changes caused by command "tfind" are now notified using
90 new async record "=traceframe-changed".
91 ** The creation and deletion of trace state variables are now notified
92 using new async records "=tsv-created" and "=tsv-deleted".
93 ** The start and stop of process record are now notified using new
94 async record "=record-started" and "=record-stopped".
95 ** Memory changes are now notified using new async record
97 ** The data-disassemble command response will include a "fullname" field
98 containing the absolute file name when GDB can determine it and source
100 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
101 command, to allow pattern filling of memory areas.
103 *** Changes in GDB 7.5
105 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
106 for more x32 ABI info.
108 * GDB now supports access to MIPS DSP registers on Linux targets.
110 * GDB now supports debugging microMIPS binaries.
112 * The "info os" command on GNU/Linux can now display information on
113 several new classes of objects managed by the operating system:
114 "info os procgroups" lists process groups
115 "info os files" lists file descriptors
116 "info os sockets" lists internet-domain sockets
117 "info os shm" lists shared-memory regions
118 "info os semaphores" lists semaphores
119 "info os msg" lists message queues
120 "info os modules" lists loaded kernel modules
122 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
123 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
124 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
125 options and inspect the probe arguments using the new $_probe_arg family
126 of convenience variables. You can obtain more information about SystemTap
127 in <http://sourceware.org/systemtap/>.
129 * GDB now supports reversible debugging on ARM, it allows you to
130 debug basic ARM and THUMB instructions, and provides
131 record/replay support.
133 * The option "symbol-reloading" has been deleted as it is no longer used.
137 ** GDB commands implemented in Python can now be put in command class
140 ** The "maint set python print-stack on|off" is now deleted.
142 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
143 apply "flag enum"-style pretty-printing to any enum.
145 ** gdb.lookup_symbol can now work when there is no current frame.
147 ** gdb.Symbol now has a 'line' attribute, holding the line number in
148 the source at which the symbol was defined.
150 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
151 method 'value'. The former indicates whether the symbol needs a
152 frame in order to compute its value, and the latter computes the
155 ** A new method 'referenced_value' on gdb.Value objects which can
156 dereference pointer as well as C++ reference values.
158 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
159 which return the global and static blocks (as gdb.Block objects),
160 of the underlying symbol table, respectively.
162 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
163 object associated with a PC value.
165 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
166 of the address range occupied by code for the current source line.
168 * Go language support.
169 GDB now supports debugging programs written in the Go programming
172 * GDBserver now supports stdio connections.
173 E.g. (gdb) target remote | ssh myhost gdbserver - hello
175 * The binary "gdbtui" can no longer be built or installed.
176 Use "gdb -tui" instead.
178 * GDB will now print "flag" enums specially. A flag enum is one where
179 all the enumerator values have no bits in common when pairwise
180 "and"ed. When printing a value whose type is a flag enum, GDB will
181 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
182 (gdb) print (enum E) 3
185 * The filename part of a linespec will now match trailing components
186 of a source file name. For example, "break gcc/expr.c:1000" will
187 now set a breakpoint in build/gcc/expr.c, but not
190 * The "info proc" and "generate-core-file" commands will now also
191 work on remote targets connected to GDBserver on Linux.
193 * The command "info catch" has been removed. It has been disabled
196 * The "catch exception" and "catch assert" commands now accept
197 a condition at the end of the command, much like the "break"
198 command does. For instance:
200 (gdb) catch exception Constraint_Error if Barrier = True
202 Previously, it was possible to add a condition to such catchpoints,
203 but it had to be done as a second step, after the catchpoint had been
204 created, using the "condition" command.
206 * The "info static-tracepoint-marker" command will now also work on
207 native Linux targets with in-process agent.
209 * GDB can now set breakpoints on inlined functions.
211 * The .gdb_index section has been updated to include symbols for
212 inlined functions. GDB will ignore older .gdb_index sections by
213 default, which could cause symbol files to be loaded more slowly
214 until their .gdb_index sections can be recreated. The new command
215 "set use-deprecated-index-sections on" will cause GDB to use any older
216 .gdb_index sections it finds. This will restore performance, but the
217 ability to set breakpoints on inlined functions will be lost in symbol
218 files with older .gdb_index sections.
220 The .gdb_index section has also been updated to record more information
221 about each symbol. This speeds up the "info variables", "info functions"
222 and "info types" commands when used with programs having the .gdb_index
223 section, as well as speeding up debugging with shared libraries using
224 the .gdb_index section.
226 * Ada support for GDB/MI Variable Objects has been added.
228 * GDB can now support 'breakpoint always-inserted mode' in 'record'
233 ** New command -info-os is the MI equivalent of "info os".
235 ** Output logs ("set logging" and related) now include MI output.
239 ** "set use-deprecated-index-sections on|off"
240 "show use-deprecated-index-sections on|off"
241 Controls the use of deprecated .gdb_index sections.
243 ** "catch load" and "catch unload" can be used to stop when a shared
244 library is loaded or unloaded, respectively.
246 ** "enable count" can be used to auto-disable a breakpoint after
249 ** "info vtbl" can be used to show the virtual method tables for
250 C++ and Java objects.
252 ** "explore" and its sub commands "explore value" and "explore type"
253 can be used to reccursively explore values and types of
254 expressions. These commands are available only if GDB is
255 configured with '--with-python'.
257 ** "info auto-load" shows status of all kinds of auto-loaded files,
258 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
259 sequences of commands files, "info auto-load python-scripts"
260 shows status of auto-loading Python script files,
261 "info auto-load local-gdbinit" shows status of loading init file
262 (.gdbinit) from current directory and "info auto-load libthread-db" shows
263 status of inferior specific thread debugging shared library loading.
265 ** "info auto-load-scripts", "set auto-load-scripts on|off"
266 and "show auto-load-scripts" commands have been deprecated, use their
267 "info auto-load python-scripts", "set auto-load python-scripts on|off"
268 and "show auto-load python-scripts" counterparts instead.
270 ** "dprintf location,format,args..." creates a dynamic printf, which
271 is basically a breakpoint that does a printf and immediately
272 resumes your program's execution, so it is like a printf that you
273 can insert dynamically at runtime instead of at compiletime.
275 ** "set print symbol"
277 Controls whether GDB attempts to display the symbol, if any,
278 corresponding to addresses it prints. This defaults to "on", but
279 you can set it to "off" to restore GDB's previous behavior.
281 * Deprecated commands
283 ** For the Renesas Super-H architecture, the "regs" command has been
284 deprecated, and "info all-registers" should be used instead.
288 Renesas RL78 rl78-*-elf
289 HP OpenVMS ia64 ia64-hp-openvms*
291 * GDBserver supports evaluation of breakpoint conditions. When
292 support is advertised by GDBserver, GDB may be told to send the
293 breakpoint conditions in bytecode form to GDBserver. GDBserver
294 will only report the breakpoint trigger to GDB when its condition
300 show mips compression
301 Select the compressed ISA encoding used in functions that have no symbol
302 information available. The encoding can be set to either of:
305 and is updated automatically from ELF file flags if available.
307 set breakpoint condition-evaluation
308 show breakpoint condition-evaluation
309 Control whether breakpoint conditions are evaluated by GDB ("host") or by
310 GDBserver ("target"). Default option "auto" chooses the most efficient
312 This option can improve debugger efficiency depending on the speed of the
316 Disable auto-loading globally.
319 Show auto-loading setting of all kinds of auto-loaded files.
321 set auto-load gdb-scripts on|off
322 show auto-load gdb-scripts
323 Control auto-loading of GDB canned sequences of commands files.
325 set auto-load python-scripts on|off
326 show auto-load python-scripts
327 Control auto-loading of Python script files.
329 set auto-load local-gdbinit on|off
330 show auto-load local-gdbinit
331 Control loading of init file (.gdbinit) from current directory.
333 set auto-load libthread-db on|off
334 show auto-load libthread-db
335 Control auto-loading of inferior specific thread debugging shared library.
337 set auto-load scripts-directory <dir1>[:<dir2>...]
338 show auto-load scripts-directory
339 Set a list of directories from which to load auto-loaded scripts.
340 Automatically loaded Python scripts and GDB scripts are located in one
341 of the directories listed by this option.
342 The delimiter (':' above) may differ according to the host platform.
344 set auto-load safe-path <dir1>[:<dir2>...]
345 show auto-load safe-path
346 Set a list of directories from which it is safe to auto-load files.
347 The delimiter (':' above) may differ according to the host platform.
349 set debug auto-load on|off
351 Control display of debugging info for auto-loading the files above.
353 set dprintf-style gdb|call|agent
355 Control the way in which a dynamic printf is performed; "gdb"
356 requests a GDB printf command, while "call" causes dprintf to call a
357 function in the inferior. "agent" requests that the target agent
358 (such as GDBserver) do the printing.
360 set dprintf-function <expr>
361 show dprintf-function
362 set dprintf-channel <expr>
364 Set the function and optional first argument to the call when using
365 the "call" style of dynamic printf.
367 set disconnected-dprintf on|off
368 show disconnected-dprintf
369 Control whether agent-style dynamic printfs continue to be in effect
370 after GDB disconnects.
372 * New configure options
375 Configure default value for the 'set auto-load scripts-directory'
376 setting above. It defaults to '$debugdir:$datadir/auto-load',
377 $debugdir representing global debugging info directories (available
378 via 'show debug-file-directory') and $datadir representing GDB's data
379 directory (available via 'show data-directory').
381 --with-auto-load-safe-path
382 Configure default value for the 'set auto-load safe-path' setting
383 above. It defaults to the --with-auto-load-dir setting.
385 --without-auto-load-safe-path
386 Set 'set auto-load safe-path' to '/', effectively disabling this
391 z0/z1 conditional breakpoints extension
393 The z0/z1 breakpoint insertion packets have been extended to carry
394 a list of conditional expressions over to the remote stub depending on the
395 condition evaluation mode. The use of this extension can be controlled
396 via the "set remote conditional-breakpoints-packet" command.
400 Specify the signals which the remote stub may pass to the debugged
401 program without GDB involvement.
403 * New command line options
405 --init-command=FILE, -ix Like --command, -x but execute it
406 before loading inferior.
407 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
408 execute it before loading inferior.
410 *** Changes in GDB 7.4
412 * GDB now handles ambiguous linespecs more consistently; the existing
413 FILE:LINE support has been expanded to other types of linespecs. A
414 breakpoint will now be set on all matching locations in all
415 inferiors, and locations will be added or removed according to
418 * GDB now allows you to skip uninteresting functions and files when
419 stepping with the "skip function" and "skip file" commands.
421 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
422 and "show remote hardware-watchpoint-length-limit". These allows to
423 set or show the maximum length limit (in bytes) of a remote
424 target hardware watchpoint.
426 This allows e.g. to use "unlimited" hardware watchpoints with the
427 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
428 watchpoints are slower than real hardware watchpoints but are
429 significantly faster than gdb software watchpoints.
433 ** The register_pretty_printer function in module gdb.printing now takes
434 an optional `replace' argument. If True, the new printer replaces any
437 ** The "maint set python print-stack on|off" command has been
438 deprecated and will be deleted in GDB 7.5.
439 A new command: "set python print-stack none|full|message" has
440 replaced it. Additionally, the default for "print-stack" is
441 now "message", which just prints the error message without
444 ** A prompt substitution hook (prompt_hook) is now available to the
447 ** A new Python module, gdb.prompt has been added to the GDB Python
448 modules library. This module provides functionality for
449 escape sequences in prompts (used by set/show
450 extended-prompt). These escape sequences are replaced by their
453 ** Python commands and convenience-functions located in
454 'data-directory'/python/gdb/command and
455 'data-directory'/python/gdb/function are now automatically loaded
458 ** Blocks now provide four new attributes. global_block and
459 static_block will return the global and static blocks
460 respectively. is_static and is_global are boolean attributes
461 that indicate if the block is one of those two types.
463 ** Symbols now provide the "type" attribute, the type of the symbol.
465 ** The "gdb.breakpoint" function has been deprecated in favor of
468 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
469 of a function. This class is based on the "finish" command
470 available in the CLI.
472 ** Type objects for struct and union types now allow access to
473 the fields using standard Python dictionary (mapping) methods.
474 For example, "some_type['myfield']" now works, as does
477 ** A new event "gdb.new_objfile" has been added, triggered by loading a
480 ** A new function, "deep_items" has been added to the gdb.types
481 module in the GDB Python modules library. This function returns
482 an iterator over the fields of a struct or union type. Unlike
483 the standard Python "iteritems" method, it will recursively traverse
484 any anonymous fields.
488 ** "*stopped" events can report several new "reason"s, such as
491 ** Breakpoint changes are now notified using new async records, like
492 "=breakpoint-modified".
494 ** New command -ada-task-info.
496 * libthread-db-search-path now supports two special values: $sdir and $pdir.
497 $sdir specifies the default system locations of shared libraries.
498 $pdir specifies the directory where the libpthread used by the application
501 GDB no longer looks in $sdir and $pdir after it has searched the directories
502 mentioned in libthread-db-search-path. If you want to search those
503 directories, they must be specified in libthread-db-search-path.
504 The default value of libthread-db-search-path on GNU/Linux and Solaris
505 systems is now "$sdir:$pdir".
507 $pdir is not supported by gdbserver, it is currently ignored.
508 $sdir is supported by gdbserver.
510 * New configure option --with-iconv-bin.
511 When using the internationalization support like the one in the GNU C
512 library, GDB will invoke the "iconv" program to get a list of supported
513 character sets. If this program lives in a non-standard location, one can
514 use this option to specify where to find it.
516 * When natively debugging programs on PowerPC BookE processors running
517 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
518 watchpoints, which specify a mask in addition to an address to watch.
519 The mask specifies that some bits of an address (the bits which are
520 reset in the mask) should be ignored when matching the address accessed
521 by the inferior against the watchpoint address. See the "PowerPC Embedded"
522 section in the user manual for more details.
524 * The new option --once causes GDBserver to stop listening for connections once
525 the first connection is made. The listening port used by GDBserver will
526 become available after that.
528 * New commands "info macros" and "alias" have been added.
530 * New function parameters suffix @entry specifies value of function parameter
531 at the time the function got called. Entry values are available only since
537 "!" is now an alias of the "shell" command.
538 Note that no space is needed between "!" and SHELL COMMAND.
542 watch EXPRESSION mask MASK_VALUE
543 The watch command now supports the mask argument which allows creation
544 of masked watchpoints, if the current architecture supports this feature.
546 info auto-load-scripts [REGEXP]
547 This command was formerly named "maintenance print section-scripts".
548 It is now generally useful and is no longer a maintenance-only command.
550 info macro [-all] [--] MACRO
551 The info macro command has new options `-all' and `--'. The first for
552 printing all definitions of a macro. The second for explicitly specifying
553 the end of arguments and the beginning of the macro name in case the macro
554 name starts with a hyphen.
556 collect[/s] EXPRESSIONS
557 The tracepoint collect command now takes an optional modifier "/s"
558 that directs it to dereference pointer-to-character types and
559 collect the bytes of memory up to a zero byte. The behavior is
560 similar to what you see when you use the regular print command on a
561 string. An optional integer following the "/s" sets a bound on the
562 number of bytes that will be collected.
565 The trace start command now interprets any supplied arguments as a
566 note to be recorded with the trace run, with an effect similar to
567 setting the variable trace-notes.
570 The trace stop command now interprets any arguments as a note to be
571 mentioned along with the tstatus report that the trace was stopped
572 with a command. The effect is similar to setting the variable
575 * Tracepoints can now be enabled and disabled at any time after a trace
576 experiment has been started using the standard "enable" and "disable"
577 commands. It is now possible to start a trace experiment with no enabled
578 tracepoints; GDB will display a warning, but will allow the experiment to
579 begin, assuming that tracepoints will be enabled as needed while the trace
582 * Fast tracepoints on 32-bit x86-architectures can now be placed at
583 locations with 4-byte instructions, when they were previously
584 limited to locations with instructions of 5 bytes or longer.
588 set debug dwarf2-read
589 show debug dwarf2-read
590 Turns on or off display of debugging messages related to reading
591 DWARF debug info. The default is off.
593 set debug symtab-create
594 show debug symtab-create
595 Turns on or off display of debugging messages related to symbol table
596 creation. The default is off.
600 Set the GDB prompt, and allow escape sequences to be inserted to
601 display miscellaneous information (see 'help set extended-prompt'
602 for the list of sequences). This prompt (and any information
603 accessed through the escape sequences) is updated every time the
606 set print entry-values (both|compact|default|if-needed|no|only|preferred)
607 show print entry-values
608 Set printing of frame argument values at function entry. In some cases
609 GDB can determine the value of function argument which was passed by the
610 function caller, even if the value was modified inside the called function.
612 set debug entry-values
613 show debug entry-values
614 Control display of debugging info for determining frame argument values at
615 function entry and virtual tail call frames.
617 set basenames-may-differ
618 show basenames-may-differ
619 Set whether a source file may have multiple base names.
620 (A "base name" is the name of a file with the directory part removed.
621 Example: The base name of "/home/user/hello.c" is "hello.c".)
622 If set, GDB will canonicalize file names (e.g., expand symlinks)
623 before comparing them. Canonicalization is an expensive operation,
624 but it allows the same file be known by more than one base name.
625 If not set (the default), all source files are assumed to have just
626 one base name, and gdb will do file name comparisons more efficiently.
632 Set a user name and notes for the current and any future trace runs.
633 This is useful for long-running and/or disconnected traces, to
634 inform others (or yourself) as to who is running the trace, supply
635 contact information, or otherwise explain what is going on.
638 show trace-stop-notes
639 Set a note attached to the trace run, that is displayed when the
640 trace has been stopped by a tstop command. This is useful for
641 instance as an explanation, if you are stopping a trace run that was
642 started by someone else.
648 Dynamically enable a tracepoint in a started trace experiment.
652 Dynamically disable a tracepoint in a started trace experiment.
656 Set the user and notes of the trace run.
660 Query the current status of a tracepoint.
664 Query the minimum length of instruction at which a fast tracepoint may
667 * Dcache size (number of lines) and line-size are now runtime-configurable
668 via "set dcache line" and "set dcache line-size" commands.
672 Texas Instruments TMS320C6x tic6x-*-*
676 Renesas RL78 rl78-*-elf
678 *** Changes in GDB 7.3.1
680 * The build failure for NetBSD and OpenBSD targets have now been fixed.
682 *** Changes in GDB 7.3
684 * GDB has a new command: "thread find [REGEXP]".
685 It finds the thread id whose name, target id, or thread extra info
686 matches the given regular expression.
688 * The "catch syscall" command now works on mips*-linux* targets.
690 * The -data-disassemble MI command now supports modes 2 and 3 for
691 dumping the instruction opcodes.
693 * New command line options
695 -data-directory DIR Specify DIR as the "data-directory".
696 This is mostly for testing purposes.
698 * The "maint set python auto-load on|off" command has been renamed to
699 "set auto-load-scripts on|off".
701 * GDB has a new command: "set directories".
702 It is like the "dir" command except that it replaces the
703 source path list instead of augmenting it.
705 * GDB now understands thread names.
707 On GNU/Linux, "info threads" will display the thread name as set by
708 prctl or pthread_setname_np.
710 There is also a new command, "thread name", which can be used to
711 assign a name internally for GDB to display.
714 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
715 has been integrated into GDB.
719 ** The function gdb.Write now accepts an optional keyword 'stream'.
720 This keyword, when provided, will direct the output to either
721 stdout, stderr, or GDB's logging output.
723 ** Parameters can now be be sub-classed in Python, and in particular
724 you may implement the get_set_doc and get_show_doc functions.
725 This improves how Parameter set/show documentation is processed
726 and allows for more dynamic content.
728 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
729 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
730 have an is_valid method.
732 ** Breakpoints can now be sub-classed in Python, and in particular
733 you may implement a 'stop' function that is executed each time
734 the inferior reaches that breakpoint.
736 ** New function gdb.lookup_global_symbol looks up a global symbol.
738 ** GDB values in Python are now callable if the value represents a
739 function. For example, if 'some_value' represents a function that
740 takes two integer parameters and returns a value, you can call
741 that function like so:
743 result = some_value (10,20)
745 ** Module gdb.types has been added.
746 It contains a collection of utilities for working with gdb.Types objects:
747 get_basic_type, has_field, make_enum_dict.
749 ** Module gdb.printing has been added.
750 It contains utilities for writing and registering pretty-printers.
751 New classes: PrettyPrinter, SubPrettyPrinter,
752 RegexpCollectionPrettyPrinter.
753 New function: register_pretty_printer.
755 ** New commands "info pretty-printers", "enable pretty-printer" and
756 "disable pretty-printer" have been added.
758 ** gdb.parameter("directories") is now available.
760 ** New function gdb.newest_frame returns the newest frame in the
763 ** The gdb.InferiorThread class has a new "name" attribute. This
764 holds the thread's name.
766 ** Python Support for Inferior events.
767 Python scripts can add observers to be notified of events
768 occurring in the process being debugged.
769 The following events are currently supported:
770 - gdb.events.cont Continue event.
771 - gdb.events.exited Inferior exited event.
772 - gdb.events.stop Signal received, and Breakpoint hit events.
776 ** GDB now puts template parameters in scope when debugging in an
777 instantiation. For example, if you have:
779 template<int X> int func (void) { return X; }
781 then if you step into func<5>, "print X" will show "5". This
782 feature requires proper debuginfo support from the compiler; it
783 was added to GCC 4.5.
785 ** The motion commands "next", "finish", "until", and "advance" now
786 work better when exceptions are thrown. In particular, GDB will
787 no longer lose control of the inferior; instead, the GDB will
788 stop the inferior at the point at which the exception is caught.
789 This functionality requires a change in the exception handling
790 code that was introduced in GCC 4.5.
792 * GDB now follows GCC's rules on accessing volatile objects when
793 reading or writing target state during expression evaluation.
794 One notable difference to prior behavior is that "print x = 0"
795 no longer generates a read of x; the value of the assignment is
796 now always taken directly from the value being assigned.
798 * GDB now has some support for using labels in the program's source in
799 linespecs. For instance, you can use "advance label" to continue
800 execution to a label.
802 * GDB now has support for reading and writing a new .gdb_index
803 section. This section holds a fast index of DWARF debugging
804 information and can be used to greatly speed up GDB startup and
805 operation. See the documentation for `save gdb-index' for details.
807 * The "watch" command now accepts an optional "-location" argument.
808 When used, this causes GDB to watch the memory referred to by the
809 expression. Such a watchpoint is never deleted due to it going out
812 * GDB now supports thread debugging of core dumps on GNU/Linux.
814 GDB now activates thread debugging using the libthread_db library
815 when debugging GNU/Linux core dumps, similarly to when debugging
816 live processes. As a result, when debugging a core dump file, GDB
817 is now able to display pthread_t ids of threads. For example, "info
818 threads" shows the same output as when debugging the process when it
819 was live. In earlier releases, you'd see something like this:
822 * 1 LWP 6780 main () at main.c:10
824 While now you see this:
827 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
829 It is also now possible to inspect TLS variables when debugging core
832 When debugging a core dump generated on a machine other than the one
833 used to run GDB, you may need to point GDB at the correct
834 libthread_db library with the "set libthread-db-search-path"
835 command. See the user manual for more details on this command.
837 * When natively debugging programs on PowerPC BookE processors running
838 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
839 which stop execution of the inferior whenever it executes an instruction
840 at any address within the specified range. See the "PowerPC Embedded"
841 section in the user manual for more details.
843 * New features in the GDB remote stub, GDBserver
845 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
846 and i686 LynxOS (version 5.x).
848 ** GDBserver is now supported on Blackfin Linux.
850 * New native configurations
852 ia64 HP-UX ia64-*-hpux*
856 Analog Devices, Inc. Blackfin Processor bfin-*
858 * Ada task switching is now supported on sparc-elf targets when
859 debugging a program using the Ravenscar Profile. For more information,
860 see the "Tasking Support when using the Ravenscar Profile" section
861 in the GDB user manual.
863 * Guile support was removed.
865 * New features in the GNU simulator
867 ** The --map-info flag lists all known core mappings.
869 ** CFI flashes may be simulated via the "cfi" device.
871 *** Changes in GDB 7.2
873 * Shared library support for remote targets by default
875 When GDB is configured for a generic, non-OS specific target, like
876 for example, --target=arm-eabi or one of the many *-*-elf targets,
877 GDB now queries remote stubs for loaded shared libraries using the
878 `qXfer:libraries:read' packet. Previously, shared library support
879 was always disabled for such configurations.
883 ** Argument Dependent Lookup (ADL)
885 In C++ ADL lookup directs function search to the namespaces of its
886 arguments even if the namespace has not been imported.
896 Here the compiler will search for `foo' in the namespace of 'b'
897 and find A::foo. GDB now supports this. This construct is commonly
898 used in the Standard Template Library for operators.
900 ** Improved User Defined Operator Support
902 In addition to member operators, GDB now supports lookup of operators
903 defined in a namespace and imported with a `using' directive, operators
904 defined in the global scope, operators imported implicitly from an
905 anonymous namespace, and the ADL operators mentioned in the previous
907 GDB now also supports proper overload resolution for all the previously
908 mentioned flavors of operators.
910 ** static const class members
912 Printing of static const class members that are initialized in the
913 class definition has been fixed.
915 * Windows Thread Information Block access.
917 On Windows targets, GDB now supports displaying the Windows Thread
918 Information Block (TIB) structure. This structure is visible either
919 by using the new command `info w32 thread-information-block' or, by
920 dereferencing the new convenience variable named `$_tlb', a
921 thread-specific pointer to the TIB. This feature is also supported
922 when remote debugging using GDBserver.
926 Static tracepoints are calls in the user program into a tracing
927 library. One such library is a port of the LTTng kernel tracer to
928 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
929 When debugging with GDBserver, GDB now supports combining the GDB
930 tracepoint machinery with such libraries. For example: the user can
931 use GDB to probe a static tracepoint marker (a call from the user
932 program into the tracing library) with the new "strace" command (see
933 "New commands" below). This creates a "static tracepoint" in the
934 breakpoint list, that can be manipulated with the same feature set
935 as fast and regular tracepoints. E.g., collect registers, local and
936 global variables, collect trace state variables, and define
937 tracepoint conditions. In addition, the user can collect extra
938 static tracepoint marker specific data, by collecting the new
939 $_sdata internal variable. When analyzing the trace buffer, you can
940 inspect $_sdata like any other variable available to GDB. For more
941 information, see the "Tracepoints" chapter in GDB user manual. New
942 remote packets have been defined to support static tracepoints, see
943 the "New remote packets" section below.
945 * Better reconstruction of tracepoints after disconnected tracing
947 GDB will attempt to download the original source form of tracepoint
948 definitions when starting a trace run, and then will upload these
949 upon reconnection to the target, resulting in a more accurate
950 reconstruction of the tracepoints that are in use on the target.
954 You can now exercise direct control over the ways that GDB can
955 affect your program. For instance, you can disallow the setting of
956 breakpoints, so that the program can run continuously (assuming
957 non-stop mode). In addition, the "observer" variable is available
958 to switch all of the different controls; in observer mode, GDB
959 cannot affect the target's behavior at all, which is useful for
960 tasks like diagnosing live systems in the field.
962 * The new convenience variable $_thread holds the number of the
969 Return the address of the Windows Thread Information Block of a given thread.
973 In response to several of the tracepoint packets, the target may now
974 also respond with a number of intermediate `qRelocInsn' request
975 packets before the final result packet, to have GDB handle
976 relocating an instruction to execute at a different address. This
977 is particularly useful for stubs that support fast tracepoints. GDB
978 reports support for this feature in the qSupported packet.
982 List static tracepoint markers in the target program.
986 List static tracepoint markers at a given address in the target
989 qXfer:statictrace:read
991 Read the static trace data collected (by a `collect $_sdata'
992 tracepoint action). The remote stub reports support for this packet
993 to gdb's qSupported query.
997 Send the current settings of GDB's permission flags.
1001 Send part of the source (textual) form of a tracepoint definition,
1002 which includes location, conditional, and action list.
1004 * The source command now accepts a -s option to force searching for the
1005 script in the source search path even if the script name specifies
1008 * New features in the GDB remote stub, GDBserver
1010 - GDBserver now support tracepoints (including fast tracepoints, and
1011 static tracepoints). The feature is currently supported by the
1012 i386-linux and amd64-linux builds. See the "Tracepoints support
1013 in gdbserver" section in the manual for more information.
1015 GDBserver JIT compiles the tracepoint's conditional agent
1016 expression bytecode into native code whenever possible for low
1017 overhead dynamic tracepoints conditionals. For such tracepoints,
1018 an expression that examines program state is evaluated when the
1019 tracepoint is reached, in order to determine whether to capture
1020 trace data. If the condition is simple and false, processing the
1021 tracepoint finishes very quickly and no data is gathered.
1023 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1024 for static tracepoints support.
1026 - GDBserver now supports x86_64 Windows 64-bit debugging.
1028 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1029 it understands register description.
1031 * The --batch flag now disables pagination and queries.
1033 * X86 general purpose registers
1035 GDB now supports reading/writing byte, word and double-word x86
1036 general purpose registers directly. This means you can use, say,
1037 $ah or $ax to refer, respectively, to the byte register AH and
1038 16-bit word register AX that are actually portions of the 32-bit
1039 register EAX or 64-bit register RAX.
1041 * The `commands' command now accepts a range of breakpoints to modify.
1042 A plain `commands' following a command that creates multiple
1043 breakpoints affects all the breakpoints set by that command. This
1044 applies to breakpoints set by `rbreak', and also applies when a
1045 single `break' command creates multiple breakpoints (e.g.,
1046 breakpoints on overloaded c++ functions).
1048 * The `rbreak' command now accepts a filename specification as part of
1049 its argument, limiting the functions selected by the regex to those
1050 in the specified file.
1052 * Support for remote debugging Windows and SymbianOS shared libraries
1053 from Unix hosts has been improved. Non Windows GDB builds now can
1054 understand target reported file names that follow MS-DOS based file
1055 system semantics, such as file names that include drive letters and
1056 use the backslash character as directory separator. This makes it
1057 possible to transparently use the "set sysroot" and "set
1058 solib-search-path" on Unix hosts to point as host copies of the
1059 target's shared libraries. See the new command "set
1060 target-file-system-kind" described below, and the "Commands to
1061 specify files" section in the user manual for more information.
1065 eval template, expressions...
1066 Convert the values of one or more expressions under the control
1067 of the string template to a command line, and call it.
1069 set target-file-system-kind unix|dos-based|auto
1070 show target-file-system-kind
1071 Set or show the assumed file system kind for target reported file
1074 save breakpoints <filename>
1075 Save all current breakpoint definitions to a file suitable for use
1076 in a later debugging session. To read the saved breakpoint
1077 definitions, use the `source' command.
1079 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1082 info static-tracepoint-markers
1083 Display information about static tracepoint markers in the target.
1085 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1086 Define a static tracepoint by probing a marker at the given
1087 function, line, address, or marker ID.
1091 Enable and disable observer mode.
1093 set may-write-registers on|off
1094 set may-write-memory on|off
1095 set may-insert-breakpoints on|off
1096 set may-insert-tracepoints on|off
1097 set may-insert-fast-tracepoints on|off
1098 set may-interrupt on|off
1099 Set individual permissions for GDB effects on the target. Note that
1100 some of these settings can have undesirable or surprising
1101 consequences, particularly when changed in the middle of a session.
1102 For instance, disabling the writing of memory can prevent
1103 breakpoints from being inserted, cause single-stepping to fail, or
1104 even crash your program, if you disable after breakpoints have been
1105 inserted. However, GDB should not crash.
1107 set record memory-query on|off
1108 show record memory-query
1109 Control whether to stop the inferior if memory changes caused
1110 by an instruction cannot be recorded.
1115 The disassemble command now supports "start,+length" form of two arguments.
1119 ** GDB now provides a new directory location, called the python directory,
1120 where Python scripts written for GDB can be installed. The location
1121 of that directory is <data-directory>/python, where <data-directory>
1122 is the GDB data directory. For more details, see section `Scripting
1123 GDB using Python' in the manual.
1125 ** The GDB Python API now has access to breakpoints, symbols, symbol
1126 tables, program spaces, inferiors, threads and frame's code blocks.
1127 Additionally, GDB Parameters can now be created from the API, and
1128 manipulated via set/show in the CLI.
1130 ** New functions gdb.target_charset, gdb.target_wide_charset,
1131 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1133 ** New exception gdb.GdbError.
1135 ** Pretty-printers are now also looked up in the current program space.
1137 ** Pretty-printers can now be individually enabled and disabled.
1139 ** GDB now looks for names of Python scripts to auto-load in a
1140 special section named `.debug_gdb_scripts', in addition to looking
1141 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1143 * Tracepoint actions were unified with breakpoint commands. In particular,
1144 there are no longer differences in "info break" output for breakpoints and
1145 tracepoints and the "commands" command can be used for both tracepoints and
1146 regular breakpoints.
1150 ARM Symbian arm*-*-symbianelf*
1152 * D language support.
1153 GDB now supports debugging programs written in the D programming
1156 * GDB now supports the extended ptrace interface for PowerPC which is
1157 available since Linux kernel version 2.6.34. This automatically enables
1158 any hardware breakpoints and additional hardware watchpoints available in
1159 the processor. The old ptrace interface exposes just one hardware
1160 watchpoint and no hardware breakpoints.
1162 * GDB is now able to use the Data Value Compare (DVC) register available on
1163 embedded PowerPC processors to implement in hardware simple watchpoint
1164 conditions of the form:
1166 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1168 This works in native GDB running on Linux kernels with the extended ptrace
1169 interface mentioned above.
1171 *** Changes in GDB 7.1
1175 ** Namespace Support
1177 GDB now supports importing of namespaces in C++. This enables the
1178 user to inspect variables from imported namespaces. Support for
1179 namepace aliasing has also been added. So, if a namespace is
1180 aliased in the current scope (e.g. namepace C=A; ) the user can
1181 print variables using the alias (e.g. (gdb) print C::x).
1185 All known bugs relating to the printing of virtual base class were
1186 fixed. It is now possible to call overloaded static methods using a
1191 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1192 and reinterpret_cast<> are now handled by the C++ expression parser.
1196 Xilinx MicroBlaze microblaze-*-*
1201 Xilinx MicroBlaze microblaze
1204 * Multi-program debugging.
1206 GDB now has support for multi-program (a.k.a. multi-executable or
1207 multi-exec) debugging. This allows for debugging multiple inferiors
1208 simultaneously each running a different program under the same GDB
1209 session. See "Debugging Multiple Inferiors and Programs" in the
1210 manual for more information. This implied some user visible changes
1211 in the multi-inferior support. For example, "info inferiors" now
1212 lists inferiors that are not running yet or that have exited
1213 already. See also "New commands" and "New options" below.
1215 * New tracing features
1217 GDB's tracepoint facility now includes several new features:
1219 ** Trace state variables
1221 GDB tracepoints now include support for trace state variables, which
1222 are variables managed by the target agent during a tracing
1223 experiment. They are useful for tracepoints that trigger each
1224 other, so for instance one tracepoint can count hits in a variable,
1225 and then a second tracepoint has a condition that is true when the
1226 count reaches a particular value. Trace state variables share the
1227 $-syntax of GDB convenience variables, and can appear in both
1228 tracepoint actions and condition expressions. Use the "tvariable"
1229 command to create, and "info tvariables" to view; see "Trace State
1230 Variables" in the manual for more detail.
1234 GDB now includes an option for defining fast tracepoints, which
1235 targets may implement more efficiently, such as by installing a jump
1236 into the target agent rather than a trap instruction. The resulting
1237 speedup can be by two orders of magnitude or more, although the
1238 tradeoff is that some program locations on some target architectures
1239 might not allow fast tracepoint installation, for instance if the
1240 instruction to be replaced is shorter than the jump. To request a
1241 fast tracepoint, use the "ftrace" command, with syntax identical to
1242 the regular trace command.
1244 ** Disconnected tracing
1246 It is now possible to detach GDB from the target while it is running
1247 a trace experiment, then reconnect later to see how the experiment
1248 is going. In addition, a new variable disconnected-tracing lets you
1249 tell the target agent whether to continue running a trace if the
1250 connection is lost unexpectedly.
1254 GDB now has the ability to save the trace buffer into a file, and
1255 then use that file as a target, similarly to you can do with
1256 corefiles. You can select trace frames, print data that was
1257 collected in them, and use tstatus to display the state of the
1258 tracing run at the moment that it was saved. To create a trace
1259 file, use "tsave <filename>", and to use it, do "target tfile
1262 ** Circular trace buffer
1264 You can ask the target agent to handle the trace buffer as a
1265 circular buffer, discarding the oldest trace frames to make room for
1266 newer ones, by setting circular-trace-buffer to on. This feature may
1267 not be available for all target agents.
1272 The disassemble command, when invoked with two arguments, now requires
1273 the arguments to be comma-separated.
1276 The info variables command now displays variable definitions. Files
1277 which only declare a variable are not shown.
1280 The source command is now capable of sourcing Python scripts.
1281 This feature is dependent on the debugger being build with Python
1284 Related to this enhancement is also the introduction of a new command
1285 "set script-extension" (see below).
1287 * New commands (for set/show, see "New options" below)
1289 record save [<FILENAME>]
1290 Save a file (in core file format) containing the process record
1291 execution log for replay debugging at a later time.
1293 record restore <FILENAME>
1294 Restore the process record execution log that was saved at an
1295 earlier time, for replay debugging.
1297 add-inferior [-copies <N>] [-exec <FILENAME>]
1300 clone-inferior [-copies <N>] [ID]
1301 Make a new inferior ready to execute the same program another
1302 inferior has loaded.
1307 maint info program-spaces
1308 List the program spaces loaded into GDB.
1310 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1311 show remote interrupt-sequence
1312 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1313 as the sequence to the remote target in order to interrupt the execution.
1314 Ctrl-C is a default. Some system prefers BREAK which is high level of
1315 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1316 Magic SysRq g. It is BREAK signal and character 'g'.
1318 set remote interrupt-on-connect [on | off]
1319 show remote interrupt-on-connect
1320 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1321 remote target when gdb connects to it. This is needed when you debug
1324 set remotebreak [on | off]
1326 Deprecated. Use "set/show remote interrupt-sequence" instead.
1328 tvariable $NAME [ = EXP ]
1329 Create or modify a trace state variable.
1332 List trace state variables and their values.
1334 delete tvariable $NAME ...
1335 Delete one or more trace state variables.
1338 Evaluate the given expressions without collecting anything into the
1339 trace buffer. (Valid in tracepoint actions only.)
1341 ftrace FN / FILE:LINE / *ADDR
1342 Define a fast tracepoint at the given function, line, or address.
1344 * New expression syntax
1346 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1347 GDB now parses 0b101010 identically with 42.
1351 set follow-exec-mode new|same
1352 show follow-exec-mode
1353 Control whether GDB reuses the same inferior across an exec call or
1354 creates a new one. This is useful to be able to restart the old
1355 executable after the inferior having done an exec call.
1357 set default-collect EXPR, ...
1358 show default-collect
1359 Define a list of expressions to be collected at each tracepoint.
1360 This is a useful way to ensure essential items are not overlooked,
1361 such as registers or a critical global variable.
1363 set disconnected-tracing
1364 show disconnected-tracing
1365 If set to 1, the target is instructed to continue tracing if it
1366 loses its connection to GDB. If 0, the target is to stop tracing
1369 set circular-trace-buffer
1370 show circular-trace-buffer
1371 If set to on, the target is instructed to use a circular trace buffer
1372 and discard the oldest trace frames instead of stopping the trace due
1373 to a full trace buffer. If set to off, the trace stops when the buffer
1374 fills up. Some targets may not support this.
1376 set script-extension off|soft|strict
1377 show script-extension
1378 If set to "off", the debugger does not perform any script language
1379 recognition, and all sourced files are assumed to be GDB scripts.
1380 If set to "soft" (the default), files are sourced according to
1381 filename extension, falling back to GDB scripts if the first
1383 If set to "strict", files are sourced according to filename extension.
1385 set ada trust-PAD-over-XVS on|off
1386 show ada trust-PAD-over-XVS
1387 If off, activate a workaround against a bug in the debugging information
1388 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1389 the GCC sources for more information about the GNAT encoding and
1390 PAD types in particular). It is always safe to set this option to
1391 off, but this introduces a slight performance penalty. The default
1394 * Python API Improvements
1396 ** GDB provides the new class gdb.LazyString. This is useful in
1397 some pretty-printing cases. The new method gdb.Value.lazy_string
1398 provides a simple way to create objects of this type.
1400 ** The fields returned by gdb.Type.fields now have an
1401 `is_base_class' attribute.
1403 ** The new method gdb.Type.range returns the range of an array type.
1405 ** The new method gdb.parse_and_eval can be used to parse and
1406 evaluate an expression.
1408 * New remote packets
1411 Define a trace state variable.
1414 Get the current value of a trace state variable.
1417 Set desired tracing behavior upon disconnection.
1420 Set the trace buffer to be linear or circular.
1423 Get data about the tracepoints currently in use.
1427 Process record now works correctly with hardware watchpoints.
1429 Multiple bug fixes have been made to the mips-irix port, making it
1430 much more reliable. In particular:
1431 - Debugging threaded applications is now possible again. Previously,
1432 GDB would hang while starting the program, or while waiting for
1433 the program to stop at a breakpoint.
1434 - Attaching to a running process no longer hangs.
1435 - An error occurring while loading a core file has been fixed.
1436 - Changing the value of the PC register now works again. This fixes
1437 problems observed when using the "jump" command, or when calling
1438 a function from GDB, or even when assigning a new value to $pc.
1439 - With the "finish" and "return" commands, the return value for functions
1440 returning a small array is now correctly printed.
1441 - It is now possible to break on shared library code which gets executed
1442 during a shared library init phase (code executed while executing
1443 their .init section). Previously, the breakpoint would have no effect.
1444 - GDB is now able to backtrace through the signal handler for
1445 non-threaded programs.
1447 PIE (Position Independent Executable) programs debugging is now supported.
1448 This includes debugging execution of PIC (Position Independent Code) shared
1449 libraries although for that, it should be possible to run such libraries as an
1452 *** Changes in GDB 7.0
1454 * GDB now has an interface for JIT compilation. Applications that
1455 dynamically generate code can create symbol files in memory and register
1456 them with GDB. For users, the feature should work transparently, and
1457 for JIT developers, the interface is documented in the GDB manual in the
1458 "JIT Compilation Interface" chapter.
1460 * Tracepoints may now be conditional. The syntax is as for
1461 breakpoints; either an "if" clause appended to the "trace" command,
1462 or the "condition" command is available. GDB sends the condition to
1463 the target for evaluation using the same bytecode format as is used
1464 for tracepoint actions.
1466 * The disassemble command now supports: an optional /r modifier, print the
1467 raw instructions in hex as well as in symbolic form, and an optional /m
1468 modifier to print mixed source+assembly.
1470 * Process record and replay
1472 In a architecture environment that supports ``process record and
1473 replay'', ``process record and replay'' target can record a log of
1474 the process execution, and replay it with both forward and reverse
1477 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1478 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1479 set execution-direction {forward|reverse}, for targets that support
1482 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1483 feature is available with a native GDB running on kernel version
1486 * GDB now has support for multi-byte and wide character sets on the
1487 target. Strings whose character type is wchar_t, char16_t, or
1488 char32_t are now correctly printed. GDB supports wide- and unicode-
1489 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1490 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1491 `printf'. This feature requires iconv to work properly; if your
1492 system does not have a working iconv, GDB can use GNU libiconv. See
1493 the installation instructions for more information.
1495 * GDB now supports automatic retrieval of shared library files from
1496 remote targets. To use this feature, specify a system root that begins
1497 with the `remote:' prefix, either via the `set sysroot' command or via
1498 the `--with-sysroot' configure-time option.
1500 * "info sharedlibrary" now takes an optional regex of libraries to show,
1501 and it now reports if a shared library has no debugging information.
1503 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1504 now complete on file names.
1506 * When completing in expressions, gdb will attempt to limit
1507 completions to allowable structure or union fields, where appropriate.
1508 For instance, consider:
1510 # struct example { int f1; double f2; };
1511 # struct example variable;
1514 If the user types TAB at the end of this command line, the available
1515 completions will be "f1" and "f2".
1517 * Inlined functions are now supported. They show up in backtraces, and
1518 the "step", "next", and "finish" commands handle them automatically.
1520 * GDB now supports the token-splicing (##) and stringification (#)
1521 operators when expanding macros. It also supports variable-arity
1524 * GDB now supports inspecting extra signal information, exported by
1525 the new $_siginfo convenience variable. The feature is currently
1526 implemented on linux ARM, i386 and amd64.
1528 * GDB can now display the VFP floating point registers and NEON vector
1529 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1530 can provide these registers (requires Linux 2.6.30 or later). Remote
1531 and simulator targets may also provide them.
1533 * New remote packets
1536 Search memory for a sequence of bytes.
1539 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1540 operation over reliable transport links. Use of this packet is
1541 controlled by the `set remote noack-packet' command.
1544 Kill the process with the specified process ID. Use this in preference
1545 to `k' when multiprocess protocol extensions are supported.
1548 Obtains additional operating system information
1552 Read or write additional signal information.
1554 * Removed remote protocol undocumented extension
1556 An undocumented extension to the remote protocol's `S' stop reply
1557 packet that permited the stub to pass a process id was removed.
1558 Remote servers should use the `T' stop reply packet instead.
1560 * GDB now supports multiple function calling conventions according to the
1561 DWARF-2 DW_AT_calling_convention function attribute.
1563 * The SH target utilizes the aforementioned change to distinguish between gcc
1564 and Renesas calling convention. It also adds the new CLI commands
1565 `set/show sh calling-convention'.
1567 * GDB can now read compressed debug sections, as produced by GNU gold
1568 with the --compress-debug-sections=zlib flag.
1570 * 64-bit core files are now supported on AIX.
1572 * Thread switching is now supported on Tru64.
1574 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1575 which will be allocated using malloc later in program execution.
1577 * The qXfer:libraries:read remote procotol packet now allows passing a
1578 list of section offsets.
1580 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1581 conditions handling signals delivered during attach or thread creation
1582 have also been fixed.
1584 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1585 From the user's standpoint, all unqualified instances of True and False
1586 are treated as the standard definitions, regardless of context.
1588 * GDB now parses C++ symbol and type names more flexibly. For
1591 template<typename T> class C { };
1594 GDB will now correctly handle all of:
1596 ptype C<char const *>
1597 ptype C<char const*>
1598 ptype C<const char *>
1599 ptype C<const char*>
1601 * New features in the GDB remote stub, gdbserver
1603 - The "--wrapper" command-line argument tells gdbserver to use a
1604 wrapper program to launch programs for debugging.
1606 - On PowerPC and S/390 targets, it is now possible to use a single
1607 gdbserver executable to debug both 32-bit and 64-bit programs.
1608 (This requires gdbserver itself to be built as a 64-bit executable.)
1610 - gdbserver uses the new noack protocol mode for TCP connections to
1611 reduce communications latency, if also supported and enabled in GDB.
1613 - Support for the sparc64-linux-gnu target is now included in
1616 - The amd64-linux build of gdbserver now supports debugging both
1617 32-bit and 64-bit programs.
1619 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1620 now support hardware watchpoints, and will use them automatically
1625 GDB now has support for scripting using Python. Whether this is
1626 available is determined at configure time.
1628 New GDB commands can now be written in Python.
1630 * Ada tasking support
1632 Ada tasks can now be inspected in GDB. The following commands have
1636 Print the list of Ada tasks.
1638 Print detailed information about task number N.
1640 Print the task number of the current task.
1642 Switch the context of debugging to task number N.
1644 * Support for user-defined prefixed commands. The "define" command can
1645 add new commands to existing prefixes, e.g. "target".
1647 * Multi-inferior, multi-process debugging.
1649 GDB now has generalized support for multi-inferior debugging. See
1650 "Debugging Multiple Inferiors" in the manual for more information.
1651 Although availability still depends on target support, the command
1652 set is more uniform now. The GNU/Linux specific multi-forks support
1653 has been migrated to this new framework. This implied some user
1654 visible changes; see "New commands" and also "Removed commands"
1657 * Target descriptions can now describe the target OS ABI. See the
1658 "Target Description Format" section in the user manual for more
1661 * Target descriptions can now describe "compatible" architectures
1662 to indicate that the target can execute applications for a different
1663 architecture in addition to those for the main target architecture.
1664 See the "Target Description Format" section in the user manual for
1667 * Multi-architecture debugging.
1669 GDB now includes general supports for debugging applications on
1670 hybrid systems that use more than one single processor architecture
1671 at the same time. Each such hybrid architecture still requires
1672 specific support to be added. The only hybrid architecture supported
1673 in this version of GDB is the Cell Broadband Engine.
1675 * GDB now supports integrated debugging of Cell/B.E. applications that
1676 use both the PPU and SPU architectures. To enable support for hybrid
1677 Cell/B.E. debugging, you need to configure GDB to support both the
1678 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1679 --enable-targets configure option.
1681 * Non-stop mode debugging.
1683 For some targets, GDB now supports an optional mode of operation in
1684 which you can examine stopped threads while other threads continue
1685 to execute freely. This is referred to as non-stop mode, with the
1686 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1687 section in the user manual for more information.
1689 To be able to support remote non-stop debugging, a remote stub needs
1690 to implement the non-stop mode remote protocol extensions, as
1691 described in the "Remote Non-Stop" section of the user manual. The
1692 GDB remote stub, gdbserver, has been adjusted to support these
1693 extensions on linux targets.
1695 * New commands (for set/show, see "New options" below)
1697 catch syscall [NAME(S) | NUMBER(S)]
1698 Catch system calls. Arguments, which should be names of system
1699 calls or their numbers, mean catch only those syscalls. Without
1700 arguments, every syscall will be caught. When the inferior issues
1701 any of the specified syscalls, GDB will stop and announce the system
1702 call, both when it is called and when its call returns. This
1703 feature is currently available with a native GDB running on the
1704 Linux Kernel, under the following architectures: x86, x86_64,
1705 PowerPC and PowerPC64.
1707 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1709 Search memory for a sequence of bytes.
1711 maint set python print-stack
1712 maint show python print-stack
1713 Show a stack trace when an error is encountered in a Python script.
1716 Invoke CODE by passing it to the Python interpreter.
1721 These allow macros to be defined, undefined, and listed
1725 Show operating system information about processes.
1728 List the inferiors currently under GDB's control.
1731 Switch focus to inferior number NUM.
1734 Detach from inferior number NUM.
1737 Kill inferior number NUM.
1741 set spu stop-on-load
1742 show spu stop-on-load
1743 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1745 set spu auto-flush-cache
1746 show spu auto-flush-cache
1747 Control whether to automatically flush the software-managed cache
1748 during Cell/B.E. debugging.
1750 set sh calling-convention
1751 show sh calling-convention
1752 Control the calling convention used when calling SH target functions.
1755 show debug timestamp
1756 Control display of timestamps with GDB debugging output.
1758 set disassemble-next-line
1759 show disassemble-next-line
1760 Control display of disassembled source lines or instructions when
1763 set remote noack-packet
1764 show remote noack-packet
1765 Set/show the use of remote protocol QStartNoAckMode packet. See above
1766 under "New remote packets."
1768 set remote query-attached-packet
1769 show remote query-attached-packet
1770 Control use of remote protocol `qAttached' (query-attached) packet.
1772 set remote read-siginfo-object
1773 show remote read-siginfo-object
1774 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1777 set remote write-siginfo-object
1778 show remote write-siginfo-object
1779 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1782 set remote reverse-continue
1783 show remote reverse-continue
1784 Control use of remote protocol 'bc' (reverse-continue) packet.
1786 set remote reverse-step
1787 show remote reverse-step
1788 Control use of remote protocol 'bs' (reverse-step) packet.
1790 set displaced-stepping
1791 show displaced-stepping
1792 Control displaced stepping mode. Displaced stepping is a way to
1793 single-step over breakpoints without removing them from the debuggee.
1794 Also known as "out-of-line single-stepping".
1797 show debug displaced
1798 Control display of debugging info for displaced stepping.
1800 maint set internal-error
1801 maint show internal-error
1802 Control what GDB does when an internal error is detected.
1804 maint set internal-warning
1805 maint show internal-warning
1806 Control what GDB does when an internal warning is detected.
1811 Use a wrapper program to launch programs for debugging.
1813 set multiple-symbols (all|ask|cancel)
1814 show multiple-symbols
1815 The value of this variable can be changed to adjust the debugger behavior
1816 when an expression or a breakpoint location contains an ambiguous symbol
1817 name (an overloaded function name, for instance).
1819 set breakpoint always-inserted
1820 show breakpoint always-inserted
1821 Keep breakpoints always inserted in the target, as opposed to inserting
1822 them when resuming the target, and removing them when the target stops.
1823 This option can improve debugger performance on slow remote targets.
1825 set arm fallback-mode (arm|thumb|auto)
1826 show arm fallback-mode
1827 set arm force-mode (arm|thumb|auto)
1829 These commands control how ARM GDB determines whether instructions
1830 are ARM or Thumb. The default for both settings is auto, which uses
1831 the current CPSR value for instructions without symbols; previous
1832 versions of GDB behaved as if "set arm fallback-mode arm".
1834 set disable-randomization
1835 show disable-randomization
1836 Standalone programs run with the virtual address space randomization enabled
1837 by default on some platforms. This option keeps the addresses stable across
1838 multiple debugging sessions.
1842 Control whether other threads are stopped or not when some thread hits
1847 Requests that asynchronous execution is enabled in the target, if available.
1848 In this case, it's possible to resume target in the background, and interact
1849 with GDB while the target is running. "show target-async" displays the
1850 current state of asynchronous execution of the target.
1852 set target-wide-charset
1853 show target-wide-charset
1854 The target-wide-charset is the name of the character set that GDB
1855 uses when printing characters whose type is wchar_t.
1857 set tcp auto-retry (on|off)
1859 set tcp connect-timeout
1860 show tcp connect-timeout
1861 These commands allow GDB to retry failed TCP connections to a remote stub
1862 with a specified timeout period; this is useful if the stub is launched
1863 in parallel with GDB but may not be ready to accept connections immediately.
1865 set libthread-db-search-path
1866 show libthread-db-search-path
1867 Control list of directories which GDB will search for appropriate
1870 set schedule-multiple (on|off)
1871 show schedule-multiple
1872 Allow GDB to resume all threads of all processes or only threads of
1873 the current process.
1877 Use more aggressive caching for accesses to the stack. This improves
1878 performance of remote debugging (particularly backtraces) without
1879 affecting correctness.
1881 set interactive-mode (on|off|auto)
1882 show interactive-mode
1883 Control whether GDB runs in interactive mode (on) or not (off).
1884 When in interactive mode, GDB waits for the user to answer all
1885 queries. Otherwise, GDB does not wait and assumes the default
1886 answer. When set to auto (the default), GDB determines which
1887 mode to use based on the stdin settings.
1892 For program forks, this is replaced by the new more generic `info
1893 inferiors' command. To list checkpoints, you can still use the
1894 `info checkpoints' command, which was an alias for the `info forks'
1898 Replaced by the new `inferior' command. To switch between
1899 checkpoints, you can still use the `restart' command, which was an
1900 alias for the `fork' command.
1903 This is removed, since some targets don't have a notion of
1904 processes. To switch between processes, you can still use the
1905 `inferior' command using GDB's own inferior number.
1908 For program forks, this is replaced by the new more generic `kill
1909 inferior' command. To delete a checkpoint, you can still use the
1910 `delete checkpoint' command, which was an alias for the `delete
1914 For program forks, this is replaced by the new more generic `detach
1915 inferior' command. To detach a checkpoint, you can still use the
1916 `detach checkpoint' command, which was an alias for the `detach
1919 * New native configurations
1921 x86/x86_64 Darwin i[34567]86-*-darwin*
1923 x86_64 MinGW x86_64-*-mingw*
1927 Lattice Mico32 lm32-*
1928 x86 DICOS i[34567]86-*-dicos*
1929 x86_64 DICOS x86_64-*-dicos*
1932 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1933 (mingw32ce) debugging.
1939 These commands were actually not implemented on any target.
1941 *** Changes in GDB 6.8
1943 * New native configurations
1945 NetBSD/hppa hppa*-*netbsd*
1946 Xtensa GNU/Linux xtensa*-*-linux*
1950 NetBSD/hppa hppa*-*-netbsd*
1951 Xtensa GNU/Lunux xtensa*-*-linux*
1953 * Change in command line behavior -- corefiles vs. process ids.
1955 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1956 attaching to process NUMBER fails, GDB no longer attempts to open a
1957 core file named NUMBER. Attaching to a program using the -c option
1958 is no longer supported. Instead, use the '-p' or '--pid' options.
1960 * GDB can now be built as a native debugger for debugging Windows x86
1961 (mingw32) Portable Executable (PE) programs.
1963 * Pending breakpoints no longer change their number when their address
1966 * GDB now supports breakpoints with multiple locations,
1967 including breakpoints on C++ constructors, inside C++ templates,
1968 and in inlined functions.
1970 * GDB's ability to debug optimized code has been improved. GDB more
1971 accurately identifies function bodies and lexical blocks that occupy
1972 more than one contiguous range of addresses.
1974 * Target descriptions can now describe registers for PowerPC.
1976 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1977 registers on PowerPC targets.
1979 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1980 targets even when the libthread_db library is not available.
1982 * The GDB remote stub, gdbserver, now supports the new file transfer
1983 commands (remote put, remote get, and remote delete).
1985 * The GDB remote stub, gdbserver, now supports run and attach in
1986 extended-remote mode.
1988 * hppa*64*-*-hpux11* target broken
1989 The debugger is unable to start a program and fails with the following
1990 error: "Error trying to get information about dynamic linker".
1991 The gdb-6.7 release is also affected.
1993 * GDB now supports the --enable-targets= configure option to allow
1994 building a single GDB executable that supports multiple remote
1995 target architectures.
1997 * GDB now supports debugging C and C++ programs which use the
1998 Decimal Floating Point extension. In addition, the PowerPC target
1999 now has a set of pseudo-registers to inspect decimal float values
2000 stored in two consecutive float registers.
2002 * The -break-insert MI command can optionally create pending
2005 * Improved support for debugging Ada
2006 Many improvements to the Ada language support have been made. These
2008 - Better support for Ada2005 interface types
2009 - Improved handling of arrays and slices in general
2010 - Better support for Taft-amendment types
2011 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2013 - Improved command completion in Ada
2016 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2021 set print frame-arguments (all|scalars|none)
2022 show print frame-arguments
2023 The value of this variable can be changed to control which argument
2024 values should be printed by the debugger when displaying a frame.
2029 Transfer files to and from a remote target, and delete remote files.
2036 Transfer files to and from a remote target, and delete remote files.
2038 * New remote packets
2045 Open, close, read, write, and delete files on the remote system.
2048 Attach to an existing process on the remote system, in extended-remote
2052 Run a new process on the remote system, in extended-remote mode.
2054 *** Changes in GDB 6.7
2056 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2057 bfd, libiberty and opcodes, as revealed by static analysis donated by
2058 Coverity, Inc. (http://scan.coverity.com).
2060 * When looking up multiply-defined global symbols, GDB will now prefer the
2061 symbol definition in the current shared library if it was built using the
2062 -Bsymbolic linker option.
2064 * When the Text User Interface (TUI) is not configured, GDB will now
2065 recognize the -tui command-line option and print a message that the TUI
2068 * The GDB remote stub, gdbserver, now has lower overhead for high
2069 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2071 * GDB for MIPS targets now autodetects whether a remote target provides
2072 32-bit or 64-bit register values.
2074 * Support for C++ member pointers has been improved.
2076 * GDB now understands XML target descriptions, which specify the
2077 target's overall architecture. GDB can read a description from
2078 a local file or over the remote serial protocol.
2080 * Vectors of single-byte data use a new integer type which is not
2081 automatically displayed as character or string data.
2083 * The /s format now works with the print command. It displays
2084 arrays of single-byte integers and pointers to single-byte integers
2087 * Target descriptions can now describe target-specific registers,
2088 for architectures which have implemented the support (currently
2089 only ARM, M68K, and MIPS).
2091 * GDB and the GDB remote stub, gdbserver, now support the XScale
2094 * The GDB remote stub, gdbserver, has been updated to support
2095 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2096 has been rewritten to use the standard GDB remote protocol.
2098 * GDB can now step into C++ functions which are called through thunks.
2100 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2102 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2103 layout. It also supports a TextSeg= and DataSeg= response when only
2104 segment base addresses (rather than offsets) are available.
2106 * The /i format now outputs any trailing branch delay slot instructions
2107 immediately following the last instruction within the count specified.
2109 * The GDB remote protocol "T" stop reply packet now supports a
2110 "library" response. Combined with the new "qXfer:libraries:read"
2111 packet, this response allows GDB to debug shared libraries on targets
2112 where the operating system manages the list of loaded libraries (e.g.
2113 Windows and SymbianOS).
2115 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2116 (DLLs) on Windows and Windows CE targets.
2118 * GDB now supports a faster verification that a .debug file matches its binary
2119 according to its build-id signature, if the signature is present.
2125 Enable or disable hardware flow control (RTS/CTS) on the serial port
2126 when debugging using remote targets.
2128 set mem inaccessible-by-default
2129 show mem inaccessible-by-default
2130 If the target supplies a memory map, for instance via the remote
2131 protocol's "qXfer:memory-map:read" packet, setting this variable
2132 prevents GDB from accessing memory outside the memory map. This
2133 is useful for targets with memory mapped registers or which react
2134 badly to accesses of unmapped address space.
2136 set breakpoint auto-hw
2137 show breakpoint auto-hw
2138 If the target supplies a memory map, for instance via the remote
2139 protocol's "qXfer:memory-map:read" packet, setting this variable
2140 lets GDB use hardware breakpoints automatically for memory regions
2141 where it can not use software breakpoints. This covers both the
2142 "break" command and internal breakpoints used for other commands
2143 including "next" and "finish".
2146 catch exception unhandled
2147 Stop the program execution when Ada exceptions are raised.
2150 Stop the program execution when an Ada assertion failed.
2154 Set an alternate system root for target files. This is a more
2155 general version of "set solib-absolute-prefix", which is now
2156 an alias to "set sysroot".
2159 Provide extended SPU facility status information. This set of
2160 commands is available only when debugging the Cell/B.E. SPU
2163 * New native configurations
2165 OpenBSD/sh sh*-*openbsd*
2168 unset tdesc filename
2170 Use the specified local file as an XML target description, and do
2171 not query the target for its built-in description.
2175 OpenBSD/sh sh*-*-openbsd*
2176 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2177 Toshiba Media Processor mep-elf
2179 * New remote packets
2182 Ignore the specified signals; pass them directly to the debugged program
2183 without stopping other threads or reporting them to GDB.
2185 qXfer:features:read:
2186 Read an XML target description from the target, which describes its
2191 Read or write contents of an spufs file on the target system. These
2192 packets are available only on the Cell/B.E. SPU architecture.
2194 qXfer:libraries:read:
2195 Report the loaded shared libraries. Combined with new "T" packet
2196 response, this packet allows GDB to debug shared libraries on
2197 targets where the operating system manages the list of loaded
2198 libraries (e.g. Windows and SymbianOS).
2202 Support for these obsolete configurations has been removed.
2210 i[34567]86-*-lynxos*
2211 i[34567]86-*-netware*
2212 i[34567]86-*-sco3.2v5*
2213 i[34567]86-*-sco3.2v4*
2215 i[34567]86-*-sysv4.2*
2218 i[34567]86-*-unixware2*
2219 i[34567]86-*-unixware*
2228 * Other removed features
2235 Various m68k-only ROM monitors.
2242 Various Renesas ROM monitors and debugging interfaces for SH and
2247 Support for a Macraigor serial interface to on-chip debugging.
2248 GDB does not directly support the newer parallel or USB
2253 A debug information format. The predecessor to DWARF 2 and
2254 DWARF 3, which are still supported.
2256 Support for the HP aCC compiler on HP-UX/PA-RISC
2258 SOM-encapsulated symbolic debugging information, automatic
2259 invocation of pxdb, and the aCC custom C++ ABI. This does not
2260 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2261 with aCC can still be debugged on an assembly level.
2263 MIPS ".pdr" sections
2265 A MIPS-specific format used to describe stack frame layout
2266 in debugging information.
2270 GDB could work with an older version of Guile to debug
2271 the interpreter and Scheme programs running in it.
2273 set mips stack-arg-size
2274 set mips saved-gpreg-size
2276 Use "set mips abi" to control parameter passing for MIPS.
2278 *** Changes in GDB 6.6
2283 Cell Broadband Engine SPU spu-elf
2285 * GDB can now be configured as a cross-debugger targeting native Windows
2286 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2287 running on a Windows system over TCP/IP to debug Windows programs.
2289 * The GDB remote stub, gdbserver, has been updated to support Windows and
2290 Cygwin debugging. Both single-threaded and multi-threaded programs are
2293 * The "set trust-readonly-sections" command works again. This command was
2294 broken in GDB 6.3, 6.4, and 6.5.
2296 * The "load" command now supports writing to flash memory, if the remote
2297 stub provides the required support.
2299 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2300 longer requires symbolic debug information (e.g. DWARF-2).
2305 unset substitute-path
2306 show substitute-path
2307 Manage a list of substitution rules that GDB uses to rewrite the name
2308 of the directories where the sources are located. This can be useful
2309 for instance when the sources were moved to a different location
2310 between compilation and debugging.
2314 Print each CLI command as it is executed. Each command is prefixed with
2315 a number of `+' symbols representing the nesting depth.
2316 The source command now has a `-v' option to enable the same feature.
2320 The ARM Demon monitor support (RDP protocol, "target rdp").
2322 Kernel Object Display, an embedded debugging feature which only worked with
2323 an obsolete version of Cisco IOS.
2325 The 'set download-write-size' and 'show download-write-size' commands.
2327 * New remote packets
2330 Tell a stub about GDB client features, and request remote target features.
2331 The first feature implemented is PacketSize, which allows the target to
2332 specify the size of packets it can handle - to minimize the number of
2333 packets required and improve performance when connected to a remote
2337 Fetch an OS auxilliary vector from the remote stub. This packet is a
2338 more efficient replacement for qPart:auxv:read.
2340 qXfer:memory-map:read:
2341 Fetch a memory map from the remote stub, including information about
2342 RAM, ROM, and flash memory devices.
2347 Erase and program a flash memory device.
2349 * Removed remote packets
2352 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2353 used it, and only gdbserver implemented it.
2355 *** Changes in GDB 6.5
2359 Renesas M32C/M16C m32c-elf
2361 Morpho Technologies ms1 ms1-elf
2365 init-if-undefined Initialize a convenience variable, but
2366 only if it doesn't already have a value.
2368 The following commands are presently only implemented for native GNU/Linux:
2370 checkpoint Save a snapshot of the program state.
2372 restart <n> Return the program state to a
2373 previously saved state.
2375 info checkpoints List currently saved checkpoints.
2377 delete-checkpoint <n> Delete a previously saved checkpoint.
2379 set|show detach-on-fork Tell gdb whether to detach from a newly
2380 forked process, or to keep debugging it.
2382 info forks List forks of the user program that
2383 are available to be debugged.
2385 fork <n> Switch to debugging one of several
2386 forks of the user program that are
2387 available to be debugged.
2389 delete-fork <n> Delete a fork from the list of forks
2390 that are available to be debugged (and
2391 kill the forked process).
2393 detach-fork <n> Delete a fork from the list of forks
2394 that are available to be debugged (and
2395 allow the process to continue).
2399 Morpho Technologies ms2 ms1-elf
2401 * Improved Windows host support
2403 GDB now builds as a cross debugger hosted on i686-mingw32, including
2404 native console support, and remote communications using either
2405 network sockets or serial ports.
2407 * Improved Modula-2 language support
2409 GDB can now print most types in the Modula-2 syntax. This includes:
2410 basic types, set types, record types, enumerated types, range types,
2411 pointer types and ARRAY types. Procedure var parameters are correctly
2412 printed and hexadecimal addresses and character constants are also
2413 written in the Modula-2 syntax. Best results can be obtained by using
2414 GNU Modula-2 together with the -gdwarf-2 command line option.
2418 The ARM rdi-share module.
2420 The Netware NLM debug server.
2422 *** Changes in GDB 6.4
2424 * New native configurations
2426 OpenBSD/arm arm*-*-openbsd*
2427 OpenBSD/mips64 mips64-*-openbsd*
2431 Morpho Technologies ms1 ms1-elf
2433 * New command line options
2435 --batch-silent As for --batch, but totally silent.
2436 --return-child-result The debugger will exist with the same value
2437 the child (debugged) program exited with.
2438 --eval-command COMMAND, -ex COMMAND
2439 Execute a single GDB CLI command. This may be
2440 specified multiple times and in conjunction
2441 with the --command (-x) option.
2443 * Deprecated commands removed
2445 The following commands, that were deprecated in 2000, have been
2449 set|show arm disassembly-flavor set|show arm disassembler
2450 othernames set arm disassembler
2451 set|show remotedebug set|show debug remote
2452 set|show archdebug set|show debug arch
2453 set|show eventdebug set|show debug event
2456 * New BSD user-level threads support
2458 It is now possible to debug programs using the user-level threads
2459 library on OpenBSD and FreeBSD. Currently supported (target)
2462 FreeBSD/amd64 x86_64-*-freebsd*
2463 FreeBSD/i386 i386-*-freebsd*
2464 OpenBSD/i386 i386-*-openbsd*
2466 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2467 are not yet supported.
2469 * New support for Matsushita MN10300 w/sim added
2470 (Work in progress). mn10300-elf.
2472 * REMOVED configurations and files
2474 VxWorks and the XDR protocol *-*-vxworks
2475 Motorola MCORE mcore-*-*
2476 National Semiconductor NS32000 ns32k-*-*
2478 * New "set print array-indexes" command
2480 After turning this setting "on", GDB prints the index of each element
2481 when displaying arrays. The default is "off" to preserve the previous
2484 * VAX floating point support
2486 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2488 * User-defined command support
2490 In addition to using $arg0..$arg9 for argument passing, it is now possible
2491 to use $argc to determine now many arguments have been passed. See the
2492 section on user-defined commands in the user manual for more information.
2494 *** Changes in GDB 6.3:
2496 * New command line option
2498 GDB now accepts -l followed by a number to set the timeout for remote
2501 * GDB works with GCC -feliminate-dwarf2-dups
2503 GDB now supports a more compact representation of DWARF-2 debug
2504 information using DW_FORM_ref_addr references. These are produced
2505 by GCC with the option -feliminate-dwarf2-dups and also by some
2506 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2507 to use -feliminate-dwarf2-dups.
2509 * Internationalization
2511 When supported by the host system, GDB will be built with
2512 internationalization (libintl). The task of marking up the sources is
2513 continued, we're looking forward to our first translation.
2517 Initial support for debugging programs compiled with the GNAT
2518 implementation of the Ada programming language has been integrated
2519 into GDB. In this release, support is limited to expression evaluation.
2521 * New native configurations
2523 GNU/Linux/m32r m32r-*-linux-gnu
2527 GDB's remote protocol now includes support for the 'p' packet. This
2528 packet is used to fetch individual registers from a remote inferior.
2530 * END-OF-LIFE registers[] compatibility module
2532 GDB's internal register infrastructure has been completely rewritten.
2533 The new infrastructure making possible the implementation of key new
2534 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2537 GDB 6.3 will be the last release to include the the registers[]
2538 compatibility module that allowed out-of-date configurations to
2539 continue to work. This change directly impacts the following
2549 powerpc bdm protocol
2551 Unless there is activity to revive these configurations, they will be
2552 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2554 * OBSOLETE configurations and files
2556 Configurations that have been declared obsolete in this release have
2557 been commented out. Unless there is activity to revive these
2558 configurations, the next release of GDB will have their sources
2559 permanently REMOVED.
2568 *** Changes in GDB 6.2.1:
2570 * MIPS `break main; run' gave an heuristic-fence-post warning
2572 When attempting to run even a simple program, a warning about
2573 heuristic-fence-post being hit would be reported. This problem has
2576 * MIPS IRIX 'long double' crashed GDB
2578 When examining a long double variable, GDB would get a segmentation
2579 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2580 IRIX long double values).
2584 A bug in the VAX stack code was causing problems with the "next"
2585 command. This problem has been fixed.
2587 *** Changes in GDB 6.2:
2589 * Fix for ``many threads''
2591 On GNU/Linux systems that use the NPTL threads library, a program
2592 rapidly creating and deleting threads would confuse GDB leading to the
2595 ptrace: No such process.
2596 thread_db_get_info: cannot get thread info: generic error
2598 This problem has been fixed.
2600 * "-async" and "-noasync" options removed.
2602 Support for the broken "-noasync" option has been removed (it caused
2605 * New ``start'' command.
2607 This command runs the program until the begining of the main procedure.
2609 * New BSD Kernel Data Access Library (libkvm) interface
2611 Using ``target kvm'' it is now possible to debug kernel core dumps and
2612 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2613 platforms. Currently supported (native-only) configurations are:
2615 FreeBSD/amd64 x86_64-*-freebsd*
2616 FreeBSD/i386 i?86-*-freebsd*
2617 NetBSD/i386 i?86-*-netbsd*
2618 NetBSD/m68k m68*-*-netbsd*
2619 NetBSD/sparc sparc-*-netbsd*
2620 OpenBSD/amd64 x86_64-*-openbsd*
2621 OpenBSD/i386 i?86-*-openbsd*
2622 OpenBSD/m68k m68*-openbsd*
2623 OpenBSD/sparc sparc-*-openbsd*
2625 * Signal trampoline code overhauled
2627 Many generic problems with GDB's signal handling code have been fixed.
2628 These include: backtraces through non-contiguous stacks; recognition
2629 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2630 call; backtrace through a signal trampoline; step into and out of
2631 signal handlers; and single-stepping in the signal trampoline.
2633 Please note that kernel bugs are a limiting factor here. These
2634 features have been shown to work on an s390 GNU/Linux system that
2635 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2637 * Cygwin support for DWARF 2 added.
2639 * New native configurations
2641 GNU/Linux/hppa hppa*-*-linux*
2642 OpenBSD/hppa hppa*-*-openbsd*
2643 OpenBSD/m68k m68*-*-openbsd*
2644 OpenBSD/m88k m88*-*-openbsd*
2645 OpenBSD/powerpc powerpc-*-openbsd*
2646 NetBSD/vax vax-*-netbsd*
2647 OpenBSD/vax vax-*-openbsd*
2649 * END-OF-LIFE frame compatibility module
2651 GDB's internal frame infrastructure has been completely rewritten.
2652 The new infrastructure making it possible to support key new features
2653 including DWARF 2 Call Frame Information. To aid in the task of
2654 migrating old configurations to this new infrastructure, a
2655 compatibility module, that allowed old configurations to continue to
2656 work, was also included.
2658 GDB 6.2 will be the last release to include this frame compatibility
2659 module. This change directly impacts the following configurations:
2669 Unless there is activity to revive these configurations, they will be
2670 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2672 * REMOVED configurations and files
2674 Sun 3, running SunOS 3 m68*-*-sunos3*
2675 Sun 3, running SunOS 4 m68*-*-sunos4*
2676 Sun 2, running SunOS 3 m68000-*-sunos3*
2677 Sun 2, running SunOS 4 m68000-*-sunos4*
2678 Motorola 680x0 running LynxOS m68*-*-lynxos*
2679 AT&T 3b1/Unix pc m68*-att-*
2680 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2681 decstation mips-dec-* mips-little-*
2682 riscos mips-*-riscos* mips-*-sysv*
2683 sonymips mips-sony-*
2684 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2686 *** Changes in GDB 6.1.1:
2688 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2690 The TUI (Text-mode User Interface) is now built as part of a default
2691 GDB configuration. It is enabled by either selecting the TUI with the
2692 command line option "-i=tui" or by running the separate "gdbtui"
2693 program. For more information on the TUI, see the manual "Debugging
2696 * Pending breakpoint support (also included in GDB 6.1)
2698 Support has been added to allow you to specify breakpoints in shared
2699 libraries that have not yet been loaded. If a breakpoint location
2700 cannot be found, and the "breakpoint pending" option is set to auto,
2701 GDB queries you if you wish to make the breakpoint pending on a future
2702 shared-library load. If and when GDB resolves the breakpoint symbol,
2703 the pending breakpoint is removed as one or more regular breakpoints
2706 Pending breakpoints are very useful for GCJ Java debugging.
2708 * Fixed ISO-C build problems
2710 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2711 non ISO-C code that stopped them being built using a more strict ISO-C
2712 compiler (e.g., IBM's C compiler).
2714 * Fixed build problem on IRIX 5
2716 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2717 wasn't able to compile compile on an IRIX 5 system.
2719 * Added execute permission to gdb/gdbserver/configure
2721 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2722 permission. This bug would cause configure to fail on a number of
2723 systems (Solaris, IRIX). Ref: server/519.
2725 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2727 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2728 has been updated to use constant array sizes.
2730 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2732 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2733 its generated DWARF Call Frame Info. This encoding was causing GDB to
2734 panic, that panic has been fixed. Ref: gdb/1628.
2736 * Fixed a problem when examining parameters in shared library code.
2738 When examining parameters in optimized shared library code generated
2739 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2740 not available''. GDB now correctly displays the variable's value.
2742 *** Changes in GDB 6.1:
2744 * Removed --with-mmalloc
2746 Support for the mmalloc memory manager has been removed, as it
2747 conflicted with the internal gdb byte cache.
2749 * Changes in AMD64 configurations
2751 The AMD64 target now includes the %cs and %ss registers. As a result
2752 the AMD64 remote protocol has changed; this affects the floating-point
2753 and SSE registers. If you rely on those registers for your debugging,
2754 you should upgrade gdbserver on the remote side.
2756 * Revised SPARC target
2758 The SPARC target has been completely revised, incorporating the
2759 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2760 support for LynxOS and SunOS 4 has been dropped. Calling functions
2761 from within GDB on operating systems with a non-executable stack
2762 (Solaris, OpenBSD) now works.
2766 GDB has a new C++ demangler which does a better job on the mangled
2767 names generated by current versions of g++. It also runs faster, so
2768 with this and other changes gdb should now start faster on large C++
2771 * DWARF 2 Location Expressions
2773 GDB support for location expressions has been extended to support function
2774 arguments and frame bases. Older versions of GDB could crash when they
2777 * C++ nested types and namespaces
2779 GDB's support for nested types and namespaces in C++ has been
2780 improved, especially if you use the DWARF 2 debugging format. (This
2781 is the default for recent versions of GCC on most platforms.)
2782 Specifically, if you have a class "Inner" defined within a class or
2783 namespace "Outer", then GDB realizes that the class's name is
2784 "Outer::Inner", not simply "Inner". This should greatly reduce the
2785 frequency of complaints about not finding RTTI symbols. In addition,
2786 if you are stopped at inside of a function defined within a namespace,
2787 GDB modifies its name lookup accordingly.
2789 * New native configurations
2791 NetBSD/amd64 x86_64-*-netbsd*
2792 OpenBSD/amd64 x86_64-*-openbsd*
2793 OpenBSD/alpha alpha*-*-openbsd*
2794 OpenBSD/sparc sparc-*-openbsd*
2795 OpenBSD/sparc64 sparc64-*-openbsd*
2797 * New debugging protocols
2799 M32R with SDI protocol m32r-*-elf*
2801 * "set prompt-escape-char" command deleted.
2803 The command "set prompt-escape-char" has been deleted. This command,
2804 and its very obscure effet on GDB's prompt, was never documented,
2805 tested, nor mentioned in the NEWS file.
2807 * OBSOLETE configurations and files
2809 Configurations that have been declared obsolete in this release have
2810 been commented out. Unless there is activity to revive these
2811 configurations, the next release of GDB will have their sources
2812 permanently REMOVED.
2814 Sun 3, running SunOS 3 m68*-*-sunos3*
2815 Sun 3, running SunOS 4 m68*-*-sunos4*
2816 Sun 2, running SunOS 3 m68000-*-sunos3*
2817 Sun 2, running SunOS 4 m68000-*-sunos4*
2818 Motorola 680x0 running LynxOS m68*-*-lynxos*
2819 AT&T 3b1/Unix pc m68*-att-*
2820 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2821 decstation mips-dec-* mips-little-*
2822 riscos mips-*-riscos* mips-*-sysv*
2823 sonymips mips-sony-*
2824 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2826 * REMOVED configurations and files
2828 SGI Irix-4.x mips-sgi-irix4 or iris4
2829 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2830 Z8000 simulator z8k-zilog-none or z8ksim
2831 Matsushita MN10200 w/simulator mn10200-*-*
2832 H8/500 simulator h8500-hitachi-hms or h8500hms
2833 HP/PA running BSD hppa*-*-bsd*
2834 HP/PA running OSF/1 hppa*-*-osf*
2835 HP/PA Pro target hppa*-*-pro*
2836 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2837 386BSD i[3456]86-*-bsd*
2838 Sequent family i[3456]86-sequent-sysv4*
2839 i[3456]86-sequent-sysv*
2840 i[3456]86-sequent-bsd*
2841 SPARC running LynxOS sparc-*-lynxos*
2842 SPARC running SunOS 4 sparc-*-sunos4*
2843 Tsqware Sparclet sparclet-*-*
2844 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2846 *** Changes in GDB 6.0:
2850 Support for debugging the Objective-C programming language has been
2851 integrated into GDB.
2853 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2855 DWARF 2's Call Frame Information makes available compiler generated
2856 information that more exactly describes the program's run-time stack.
2857 By using this information, GDB is able to provide more robust stack
2860 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2861 have been updated to use a new backtrace mechanism which includes
2862 DWARF 2 CFI support.
2866 GDB's remote protocol has been extended to include support for hosted
2867 file I/O (where the remote target uses GDB's file system). See GDB's
2868 remote protocol documentation for details.
2870 * All targets using the new architecture framework.
2872 All of GDB's targets have been updated to use the new internal
2873 architecture framework. The way is now open for future GDB releases
2874 to include cross-architecture native debugging support (i386 on amd64,
2877 * GNU/Linux's Thread Local Storage (TLS)
2879 GDB now includes support for for the GNU/Linux implementation of
2880 per-thread variables.
2882 * GNU/Linux's Native POSIX Thread Library (NPTL)
2884 GDB's thread code has been updated to work with either the new
2885 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2887 * Separate debug info.
2889 GDB, in conjunction with BINUTILS, now supports a mechanism for
2890 automatically loading debug information from a separate file. Instead
2891 of shipping full debug and non-debug versions of system libraries,
2892 system integrators can now instead ship just the stripped libraries
2893 and optional debug files.
2895 * DWARF 2 Location Expressions
2897 DWARF 2 Location Expressions allow the compiler to more completely
2898 describe the location of variables (even in optimized code) to the
2901 GDB now includes preliminary support for location expressions (support
2902 for DW_OP_piece is still missing).
2906 A number of long standing bugs that caused GDB to die while starting a
2907 Java application have been fixed. GDB's Java support is now
2908 considered "useable".
2910 * GNU/Linux support for fork, vfork, and exec.
2912 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2913 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2916 * GDB supports logging output to a file
2918 There are two new commands, "set logging" and "show logging", which can be
2919 used to capture GDB's output to a file.
2921 * The meaning of "detach" has changed for gdbserver
2923 The "detach" command will now resume the application, as documented. To
2924 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2927 * d10v, m68hc11 `regs' command deprecated
2929 The `info registers' command has been updated so that it displays the
2930 registers using a format identical to the old `regs' command.
2934 A new command, "maint set profile on/off", has been added. This command can
2935 be used to enable or disable profiling while running GDB, to profile a
2936 session or a set of commands. In addition there is a new configure switch,
2937 "--enable-profiling", which will cause GDB to be compiled with profiling
2938 data, for more informative profiling results.
2940 * Default MI syntax changed to "mi2".
2942 The default MI (machine interface) syntax, enabled by the command line
2943 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2944 "mi1", can be enabled by specifying the option "-i=mi1".
2946 Support for the original "mi0" syntax (included in GDB 5.0) has been
2949 Fix for gdb/192: removed extraneous space when displaying frame level.
2950 Fix for gdb/672: update changelist is now output in mi list format.
2951 Fix for gdb/702: a -var-assign that updates the value now shows up
2952 in a subsequent -var-update.
2954 * New native configurations.
2956 FreeBSD/amd64 x86_64-*-freebsd*
2958 * Multi-arched targets.
2960 HP/PA HPUX11 hppa*-*-hpux*
2961 Renesas M32R/D w/simulator m32r-*-elf*
2963 * OBSOLETE configurations and files
2965 Configurations that have been declared obsolete in this release have
2966 been commented out. Unless there is activity to revive these
2967 configurations, the next release of GDB will have their sources
2968 permanently REMOVED.
2970 Z8000 simulator z8k-zilog-none or z8ksim
2971 Matsushita MN10200 w/simulator mn10200-*-*
2972 H8/500 simulator h8500-hitachi-hms or h8500hms
2973 HP/PA running BSD hppa*-*-bsd*
2974 HP/PA running OSF/1 hppa*-*-osf*
2975 HP/PA Pro target hppa*-*-pro*
2976 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2977 Sequent family i[3456]86-sequent-sysv4*
2978 i[3456]86-sequent-sysv*
2979 i[3456]86-sequent-bsd*
2980 Tsqware Sparclet sparclet-*-*
2981 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2983 * REMOVED configurations and files
2986 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2987 IBM AIX PS/2 i[3456]86-*-aix
2988 i386 running Mach 3.0 i[3456]86-*-mach3*
2989 i386 running Mach i[3456]86-*-mach*
2990 i386 running OSF/1 i[3456]86-*osf1mk*
2991 HP/Apollo 68k Family m68*-apollo*-sysv*,
2993 m68*-hp-bsd*, m68*-hp-hpux*
2994 Argonaut Risc Chip (ARC) arc-*-*
2995 Mitsubishi D30V d30v-*-*
2996 Fujitsu FR30 fr30-*-elf*
2997 OS/9000 i[34]86-*-os9k
2998 I960 with MON960 i960-*-coff
3000 * MIPS $fp behavior changed
3002 The convenience variable $fp, for the MIPS, now consistently returns
3003 the address of the current frame's base. Previously, depending on the
3004 context, $fp could refer to either $sp or the current frame's base
3005 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3006 The GNU Source-Level Debugger''.
3008 *** Changes in GDB 5.3:
3010 * GNU/Linux shared library multi-threaded performance improved.
3012 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3013 `/proc', in preference to `ptrace' for memory reads. This may result
3014 in an improvement in the start-up time of multi-threaded, shared
3015 library applications when run under GDB. One GDB user writes: ``loads
3016 shared libs like mad''.
3018 * ``gdbserver'' now supports multi-threaded applications on some targets
3020 Support for debugging multi-threaded applications which use
3021 the GNU/Linux LinuxThreads package has been added for
3022 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3023 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3025 * GDB now supports C/C++ preprocessor macros.
3027 GDB now expands preprocessor macro invocations in C/C++ expressions,
3028 and provides various commands for showing macro definitions and how
3031 The new command `macro expand EXPRESSION' expands any macro
3032 invocations in expression, and shows the result.
3034 The new command `show macro MACRO-NAME' shows the definition of the
3035 macro named MACRO-NAME, and where it was defined.
3037 Most compilers don't include information about macros in the debugging
3038 information by default. In GCC 3.1, for example, you need to compile
3039 your program with the options `-gdwarf-2 -g3'. If the macro
3040 information is present in the executable, GDB will read it.
3042 * Multi-arched targets.
3044 DEC Alpha (partial) alpha*-*-*
3045 DEC VAX (partial) vax-*-*
3047 National Semiconductor NS32000 (partial) ns32k-*-*
3048 Motorola 68000 (partial) m68k-*-*
3049 Motorola MCORE mcore-*-*
3053 Fujitsu FRV architecture added by Red Hat frv*-*-*
3056 * New native configurations
3058 Alpha NetBSD alpha*-*-netbsd*
3059 SH NetBSD sh*-*-netbsdelf*
3060 MIPS NetBSD mips*-*-netbsd*
3061 UltraSPARC NetBSD sparc64-*-netbsd*
3063 * OBSOLETE configurations and files
3065 Configurations that have been declared obsolete in this release have
3066 been commented out. Unless there is activity to revive these
3067 configurations, the next release of GDB will have their sources
3068 permanently REMOVED.
3070 Mitsubishi D30V d30v-*-*
3071 OS/9000 i[34]86-*-os9k
3072 IBM AIX PS/2 i[3456]86-*-aix
3073 Fujitsu FR30 fr30-*-elf*
3074 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3075 Argonaut Risc Chip (ARC) arc-*-*
3076 i386 running Mach 3.0 i[3456]86-*-mach3*
3077 i386 running Mach i[3456]86-*-mach*
3078 i386 running OSF/1 i[3456]86-*osf1mk*
3079 HP/Apollo 68k Family m68*-apollo*-sysv*,
3081 m68*-hp-bsd*, m68*-hp-hpux*
3082 I960 with MON960 i960-*-coff
3084 * OBSOLETE languages
3086 CHILL, a Pascal like language used by telecommunications companies.
3088 * REMOVED configurations and files
3090 AMD 29k family via UDI a29k-amd-udi, udi29k
3091 A29K VxWorks a29k-*-vxworks
3092 AMD 29000 embedded, using EBMON a29k-none-none
3093 AMD 29000 embedded with COFF a29k-none-coff
3094 AMD 29000 embedded with a.out a29k-none-aout
3096 testsuite/gdb.hp/gdb.threads-hp/ directory
3098 * New command "set max-user-call-depth <nnn>"
3100 This command allows the user to limit the call depth of user-defined
3101 commands. The default is 1024.
3103 * Changes in FreeBSD/i386 native debugging.
3105 Support for the "generate-core-file" has been added.
3107 * New commands "dump", "append", and "restore".
3109 These commands allow data to be copied from target memory
3110 to a bfd-format or binary file (dump and append), and back
3111 from a file into memory (restore).
3113 * Improved "next/step" support on multi-processor Alpha Tru64.
3115 The previous single-step mechanism could cause unpredictable problems,
3116 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3117 of a software single-step mechanism prevents this.
3119 *** Changes in GDB 5.2.1:
3127 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3128 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3129 Fix, by Joel Brobecker imported from mainline.
3131 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3132 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3133 Fix, by Fred Fish, imported from mainline.
3135 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3136 Surprisingly enough, it works now.
3137 By Michal Ludvig, imported from mainline.
3139 i386 hardware watchpoint support:
3140 avoid misses on second run for some targets.
3141 By Pierre Muller, imported from mainline.
3143 *** Changes in GDB 5.2:
3145 * New command "set trust-readonly-sections on[off]".
3147 This command is a hint that tells gdb that read-only sections
3148 really are read-only (ie. that their contents will not change).
3149 In this mode, gdb will go to the object file rather than the
3150 target to read memory from read-only sections (such as ".text").
3151 This can be a significant performance improvement on some
3152 (notably embedded) targets.
3154 * New command "generate-core-file" (or "gcore").
3156 This new gdb command allows the user to drop a core file of the child
3157 process state at any time. So far it's been implemented only for
3158 GNU/Linux and Solaris, but should be relatively easily ported to other
3159 hosts. Argument is core file name (defaults to core.<pid>).
3161 * New command line option
3163 GDB now accepts --pid or -p followed by a process id.
3165 * Change in command line behavior -- corefiles vs. process ids.
3167 There is a subtle behavior in the way in which GDB handles
3168 command line arguments. The first non-flag argument is always
3169 a program to debug, but the second non-flag argument may either
3170 be a corefile or a process id. Previously, GDB would attempt to
3171 open the second argument as a corefile, and if that failed, would
3172 issue a superfluous error message and then attempt to attach it as
3173 a process. Now, if the second argument begins with a non-digit,
3174 it will be treated as a corefile. If it begins with a digit,
3175 GDB will attempt to attach it as a process, and if no such process
3176 is found, will then attempt to open it as a corefile.
3178 * Changes in ARM configurations.
3180 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3181 configuration is fully multi-arch.
3183 * New native configurations
3185 ARM NetBSD arm*-*-netbsd*
3186 x86 OpenBSD i[3456]86-*-openbsd*
3187 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3188 Sparc64 running FreeBSD sparc64-*-freebsd*
3192 Sanyo XStormy16 xstormy16-elf
3194 * OBSOLETE configurations and files
3196 Configurations that have been declared obsolete in this release have
3197 been commented out. Unless there is activity to revive these
3198 configurations, the next release of GDB will have their sources
3199 permanently REMOVED.
3201 AMD 29k family via UDI a29k-amd-udi, udi29k
3202 A29K VxWorks a29k-*-vxworks
3203 AMD 29000 embedded, using EBMON a29k-none-none
3204 AMD 29000 embedded with COFF a29k-none-coff
3205 AMD 29000 embedded with a.out a29k-none-aout
3207 testsuite/gdb.hp/gdb.threads-hp/ directory
3209 * REMOVED configurations and files
3211 TI TMS320C80 tic80-*-*
3213 PowerPC Solaris powerpcle-*-solaris*
3214 PowerPC Windows NT powerpcle-*-cygwin32
3215 PowerPC Netware powerpc-*-netware*
3216 Harris/CXUX m88k m88*-harris-cxux*
3217 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3218 ns32k-utek-sysv* ns32k-utek-*
3219 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3220 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3221 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3222 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3223 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3225 * Changes to command line processing
3227 The new `--args' feature can be used to specify command-line arguments
3228 for the inferior from gdb's command line.
3230 * Changes to key bindings
3232 There is a new `operate-and-get-next' function bound to `C-o'.
3234 *** Changes in GDB 5.1.1
3236 Fix compile problem on DJGPP.
3238 Fix a problem with floating-point registers on the i386 being
3241 Fix to stop GDB crashing on .debug_str debug info.
3243 Numerous documentation fixes.
3245 Numerous testsuite fixes.
3247 *** Changes in GDB 5.1:
3249 * New native configurations
3251 Alpha FreeBSD alpha*-*-freebsd*
3252 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3253 MIPS GNU/Linux mips*-*-linux*
3254 MIPS SGI Irix 6.x mips*-sgi-irix6*
3255 ia64 AIX ia64-*-aix*
3256 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3260 Motorola 68HC11 and 68HC12 m68hc11-elf
3262 UltraSparc running GNU/Linux sparc64-*-linux*
3264 * OBSOLETE configurations and files
3266 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3267 Harris/CXUX m88k m88*-harris-cxux*
3268 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3269 ns32k-utek-sysv* ns32k-utek-*
3270 TI TMS320C80 tic80-*-*
3272 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3273 PowerPC Solaris powerpcle-*-solaris*
3274 PowerPC Windows NT powerpcle-*-cygwin32
3275 PowerPC Netware powerpc-*-netware*
3276 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3277 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3278 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3279 Apple Macintosh (MPW) host N/A
3281 stuff.c (Program to stuff files into a specially prepared space in kdb)
3282 kdb-start.c (Main loop for the standalone kernel debugger)
3284 Configurations that have been declared obsolete in this release have
3285 been commented out. Unless there is activity to revive these
3286 configurations, the next release of GDB will have their sources
3287 permanently REMOVED.
3289 * REMOVED configurations and files
3291 Altos 3068 m68*-altos-*
3292 Convex c1-*-*, c2-*-*
3294 ARM RISCix arm-*-* (as host)
3298 * GDB has been converted to ISO C.
3300 GDB's source code has been converted to ISO C. In particular, the
3301 sources are fully protoized, and rely on standard headers being
3306 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3308 * The MI enabled by default.
3310 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3311 revised and enabled by default. Packages which use GDB as a debugging
3312 engine behind a UI or another front end are encouraged to switch to
3313 using the GDB/MI interface, instead of the old annotations interface
3314 which is now deprecated.
3316 * Support for debugging Pascal programs.
3318 GDB now includes support for debugging Pascal programs. The following
3319 main features are supported:
3321 - Pascal-specific data types such as sets;
3323 - automatic recognition of Pascal sources based on file-name
3326 - Pascal-style display of data types, variables, and functions;
3328 - a Pascal expression parser.
3330 However, some important features are not yet supported.
3332 - Pascal string operations are not supported at all;
3334 - there are some problems with boolean types;
3336 - Pascal type hexadecimal constants are not supported
3337 because they conflict with the internal variables format;
3339 - support for Pascal objects and classes is not full yet;
3341 - unlike Pascal, GDB is case-sensitive for symbol names.
3343 * Changes in completion.
3345 Commands such as `shell', `run' and `set args', which pass arguments
3346 to inferior programs, now complete on file names, similar to what
3347 users expect at the shell prompt.
3349 Commands which accept locations, such as `disassemble', `print',
3350 `breakpoint', `until', etc. now complete on filenames as well as
3351 program symbols. Thus, if you type "break foob TAB", and the source
3352 files linked into the programs include `foobar.c', that file name will
3353 be one of the candidates for completion. However, file names are not
3354 considered for completion after you typed a colon that delimits a file
3355 name from a name of a function in that file, as in "break foo.c:bar".
3357 `set demangle-style' completes on available demangling styles.
3359 * New platform-independent commands:
3361 It is now possible to define a post-hook for a command as well as a
3362 hook that runs before the command. For more details, see the
3363 documentation of `hookpost' in the GDB manual.
3365 * Changes in GNU/Linux native debugging.
3367 Support for debugging multi-threaded programs has been completely
3368 revised for all platforms except m68k and sparc. You can now debug as
3369 many threads as your system allows you to have.
3371 Attach/detach is supported for multi-threaded programs.
3373 Support for SSE registers was added for x86. This doesn't work for
3374 multi-threaded programs though.
3376 * Changes in MIPS configurations.
3378 Multi-arch support is enabled for all MIPS configurations.
3380 GDB can now be built as native debugger on SGI Irix 6.x systems for
3381 debugging n32 executables. (Debugging 64-bit executables is not yet
3384 * Unified support for hardware watchpoints in all x86 configurations.
3386 Most (if not all) native x86 configurations support hardware-assisted
3387 breakpoints and watchpoints in a unified manner. This support
3388 implements debug register sharing between watchpoints, which allows to
3389 put a virtually infinite number of watchpoints on the same address,
3390 and also supports watching regions up to 16 bytes with several debug
3393 The new maintenance command `maintenance show-debug-regs' toggles
3394 debugging print-outs in functions that insert, remove, and test
3395 watchpoints and hardware breakpoints.
3397 * Changes in the DJGPP native configuration.
3399 New command ``info dos sysinfo'' displays assorted information about
3400 the CPU, OS, memory, and DPMI server.
3402 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3403 display information about segment descriptors stored in GDT, LDT, and
3406 New commands ``info dos pde'' and ``info dos pte'' display entries
3407 from Page Directory and Page Tables (for now works with CWSDPMI only).
3408 New command ``info dos address-pte'' displays the Page Table entry for
3409 a given linear address.
3411 GDB can now pass command lines longer than 126 characters to the
3412 program being debugged (requires an update to the libdbg.a library
3413 which is part of the DJGPP development kit).
3415 DWARF2 debug info is now supported.
3417 It is now possible to `step' and `next' through calls to `longjmp'.
3419 * Changes in documentation.
3421 All GDB documentation was converted to GFDL, the GNU Free
3422 Documentation License.
3424 Tracepoints-related commands are now fully documented in the GDB
3427 TUI, the Text-mode User Interface, is now documented in the manual.
3429 Tracepoints-related commands are now fully documented in the GDB
3432 The "GDB Internals" manual now has an index. It also includes
3433 documentation of `ui_out' functions, GDB coding standards, x86
3434 hardware watchpoints, and memory region attributes.
3436 * GDB's version number moved to ``version.in''
3438 The Makefile variable VERSION has been replaced by the file
3439 ``version.in''. People creating GDB distributions should update the
3440 contents of this file.
3444 GUD support is now a standard part of the EMACS distribution.
3446 *** Changes in GDB 5.0:
3448 * Improved support for debugging FP programs on x86 targets
3450 Unified and much-improved support for debugging floating-point
3451 programs on all x86 targets. In particular, ``info float'' now
3452 displays the FP registers in the same format on all x86 targets, with
3453 greater level of detail.
3455 * Improvements and bugfixes in hardware-assisted watchpoints
3457 It is now possible to watch array elements, struct members, and
3458 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3459 on x86 targets no longer erroneously trigger when the address is
3462 * Improvements in the native DJGPP version of GDB
3464 The distribution now includes all the scripts and auxiliary files
3465 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3466 machines ``out of the box''.
3468 The DJGPP version can now debug programs that use signals. It is
3469 possible to catch signals that happened in the debuggee, deliver
3470 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3471 would kill the program being debugged.) Programs that hook hardware
3472 interrupts (keyboard, timer, etc.) can also be debugged.
3474 It is now possible to debug DJGPP programs that redirect their
3475 standard handles or switch them to raw (as opposed to cooked) mode, or
3476 even close them. The command ``run < foo > bar'' works as expected,
3477 and ``info terminal'' reports useful information about the debuggee's
3478 terminal, including raw/cooked mode, redirection, etc.
3480 The DJGPP version now uses termios functions for console I/O, which
3481 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3484 DOS-style file names with drive letters are now fully supported by
3487 It is now possible to debug DJGPP programs that switch their working
3488 directory. It is also possible to rerun the debuggee any number of
3489 times without restarting GDB; thus, you can use the same setup,
3490 breakpoints, etc. for many debugging sessions.
3492 * New native configurations
3494 ARM GNU/Linux arm*-*-linux*
3495 PowerPC GNU/Linux powerpc-*-linux*
3499 Motorola MCore mcore-*-*
3500 x86 VxWorks i[3456]86-*-vxworks*
3501 PowerPC VxWorks powerpc-*-vxworks*
3502 TI TMS320C80 tic80-*-*
3504 * OBSOLETE configurations
3506 Altos 3068 m68*-altos-*
3507 Convex c1-*-*, c2-*-*
3509 ARM RISCix arm-*-* (as host)
3512 Configurations that have been declared obsolete will be commented out,
3513 but the code will be left in place. If there is no activity to revive
3514 these configurations before the next release of GDB, the sources will
3515 be permanently REMOVED.
3517 * Gould support removed
3519 Support for the Gould PowerNode and NP1 has been removed.
3521 * New features for SVR4
3523 On SVR4 native platforms (such as Solaris), if you attach to a process
3524 without first loading a symbol file, GDB will now attempt to locate and
3525 load symbols from the running process's executable file.
3527 * Many C++ enhancements
3529 C++ support has been greatly improved. Overload resolution now works properly
3530 in almost all cases. RTTI support is on the way.
3532 * Remote targets can connect to a sub-program
3534 A popen(3) style serial-device has been added. This device starts a
3535 sub-process (such as a stand-alone simulator) and then communicates
3536 with that. The sub-program to run is specified using the syntax
3537 ``|<program> <args>'' vis:
3539 (gdb) set remotedebug 1
3540 (gdb) target extended-remote |mn10300-elf-sim program-args
3542 * MIPS 64 remote protocol
3544 A long standing bug in the mips64 remote protocol where by GDB
3545 expected certain 32 bit registers (ex SR) to be transfered as 32
3546 instead of 64 bits has been fixed.
3548 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3549 added to provide backward compatibility with older versions of GDB.
3551 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3553 The command ``set remotebinarydownload'' command has been replaced by
3554 ``set remote X-packet''. Other commands in ``set remote'' family
3555 include ``set remote P-packet''.
3557 * Breakpoint commands accept ranges.
3559 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3560 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3561 ``tracepoint passcount'' also accepts a range of tracepoints.
3563 * ``apropos'' command added.
3565 The ``apropos'' command searches through command names and
3566 documentation strings, printing out matches, making it much easier to
3567 try to find a command that does what you are looking for.
3571 A new machine oriented interface (MI) has been added to GDB. This
3572 interface is designed for debug environments running GDB as a separate
3573 process. This is part of the long term libGDB project. See the
3574 "GDB/MI" chapter of the GDB manual for further information. It can be
3575 enabled by configuring with:
3577 .../configure --enable-gdbmi
3579 *** Changes in GDB-4.18:
3581 * New native configurations
3583 HP-UX 10.20 hppa*-*-hpux10.20
3584 HP-UX 11.x hppa*-*-hpux11.0*
3585 M68K GNU/Linux m68*-*-linux*
3589 Fujitsu FR30 fr30-*-elf*
3590 Intel StrongARM strongarm-*-*
3591 Mitsubishi D30V d30v-*-*
3593 * OBSOLETE configurations
3595 Gould PowerNode, NP1 np1-*-*, pn-*-*
3597 Configurations that have been declared obsolete will be commented out,
3598 but the code will be left in place. If there is no activity to revive
3599 these configurations before the next release of GDB, the sources will
3600 be permanently REMOVED.
3604 As a compatibility experiment, GDB's source files buildsym.h and
3605 buildsym.c have been converted to pure standard C, no longer
3606 containing any K&R compatibility code. We believe that all systems in
3607 use today either come with a standard C compiler, or have a GCC port
3608 available. If this is not true, please report the affected
3609 configuration to bug-gdb@gnu.org immediately. See the README file for
3610 information about getting a standard C compiler if you don't have one
3615 GDB now uses readline 2.2.
3617 * set extension-language
3619 You can now control the mapping between filename extensions and source
3620 languages by using the `set extension-language' command. For instance,
3621 you can ask GDB to treat .c files as C++ by saying
3622 set extension-language .c c++
3623 The command `info extensions' lists all of the recognized extensions
3624 and their associated languages.
3626 * Setting processor type for PowerPC and RS/6000
3628 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3629 you can use the `set processor' command to specify what variant of the
3630 PowerPC family you are debugging. The command
3634 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3635 following PowerPC and RS6000 variants:
3637 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3638 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3640 403GC IBM PowerPC 403GC
3641 505 Motorola PowerPC 505
3642 860 Motorola PowerPC 860 or 850
3643 601 Motorola PowerPC 601
3644 602 Motorola PowerPC 602
3645 603 Motorola/IBM PowerPC 603 or 603e
3646 604 Motorola PowerPC 604 or 604e
3647 750 Motorola/IBM PowerPC 750 or 750
3649 At the moment, this command just tells GDB what to name the
3650 special-purpose processor registers. Since almost all the affected
3651 registers are inaccessible to user-level programs, this command is
3652 only useful for remote debugging in its present form.
3656 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3657 more extensive support for HP-UX. Added features include shared
3658 library support, kernel threads and hardware watchpoints for 11.00,
3659 support for HP's ANSI C and C++ compilers, and a compatibility mode
3660 for xdb and dbx commands.
3664 HP's donation includes the new concept of catchpoints, which is a
3665 generalization of the old catch command. On HP-UX, it is now possible
3666 to catch exec, fork, and vfork, as well as library loading.
3668 This means that the existing catch command has changed; its first
3669 argument now specifies the type of catch to be set up. See the
3670 output of "help catch" for a list of catchpoint types.
3672 * Debugging across forks
3674 On HP-UX, you can choose which process to debug when a fork() happens
3679 HP has donated a curses-based terminal user interface (TUI). To get
3680 it, build with --enable-tui. Although this can be enabled for any
3681 configuration, at present it only works for native HP debugging.
3683 * GDB remote protocol additions
3685 A new protocol packet 'X' that writes binary data is now available.
3686 Default behavior is to try 'X', then drop back to 'M' if the stub
3687 fails to respond. The settable variable `remotebinarydownload'
3688 allows explicit control over the use of 'X'.
3690 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3691 full 64-bit address. The command
3693 set remoteaddresssize 32
3695 can be used to revert to the old behaviour. For existing remote stubs
3696 the change should not be noticed, as the additional address information
3699 In order to assist in debugging stubs, you may use the maintenance
3700 command `packet' to send any text string to the stub. For instance,
3702 maint packet heythere
3704 sends the packet "$heythere#<checksum>". Note that it is very easy to
3705 disrupt a debugging session by sending the wrong packet at the wrong
3708 The compare-sections command allows you to compare section data on the
3709 target to what is in the executable file without uploading or
3710 downloading, by comparing CRC checksums.
3712 * Tracing can collect general expressions
3714 You may now collect general expressions at tracepoints. This requires
3715 further additions to the target-side stub; see tracepoint.c and
3716 doc/agentexpr.texi for further details.
3718 * mask-address variable for Mips
3720 For Mips targets, you may control the zeroing of the upper 32 bits of
3721 a 64-bit address by entering `set mask-address on'. This is mainly
3722 of interest to users of embedded R4xxx and R5xxx processors.
3724 * Higher serial baud rates
3726 GDB's serial code now allows you to specify baud rates 57600, 115200,
3727 230400, and 460800 baud. (Note that your host system may not be able
3728 to achieve all of these rates.)
3732 The i960 configuration now includes an initial implementation of a
3733 builtin simulator, contributed by Jim Wilson.
3736 *** Changes in GDB-4.17:
3738 * New native configurations
3740 Alpha GNU/Linux alpha*-*-linux*
3741 Unixware 2.x i[3456]86-unixware2*
3742 Irix 6.x mips*-sgi-irix6*
3743 PowerPC GNU/Linux powerpc-*-linux*
3744 PowerPC Solaris powerpcle-*-solaris*
3745 Sparc GNU/Linux sparc-*-linux*
3746 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3750 Argonaut Risc Chip (ARC) arc-*-*
3751 Hitachi H8/300S h8300*-*-*
3752 Matsushita MN10200 w/simulator mn10200-*-*
3753 Matsushita MN10300 w/simulator mn10300-*-*
3754 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3755 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3756 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3757 Mitsubishi D10V w/simulator d10v-*-*
3758 Mitsubishi M32R/D w/simulator m32r-*-elf*
3759 Tsqware Sparclet sparclet-*-*
3760 NEC V850 w/simulator v850-*-*
3762 * New debugging protocols
3764 ARM with RDI protocol arm*-*-*
3765 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3766 DDB and LSI variants of PMON protocol mips*-*-*
3767 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3768 PowerPC with SDS protocol powerpc{,le}-*-eabi
3769 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3773 All configurations can now understand and use the DWARF 2 debugging
3774 format. The choice is automatic, if the symbol file contains DWARF 2
3779 GDB now includes basic Java language support. This support is
3780 only useful with Java compilers that produce native machine code.
3782 * solib-absolute-prefix and solib-search-path
3784 For SunOS and SVR4 shared libraries, you may now set the prefix for
3785 loading absolute shared library symbol files, and the search path for
3786 locating non-absolute shared library symbol files.
3788 * Live range splitting
3790 GDB can now effectively debug code for which GCC has performed live
3791 range splitting as part of its optimization. See gdb/doc/LRS for
3792 more details on the expected format of the stabs information.
3796 GDB's support for the GNU Hurd, including thread debugging, has been
3797 updated to work with current versions of the Hurd.
3801 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3802 instruction set. ARM GDB automatically detects when Thumb
3803 instructions are in use, and adjusts disassembly and backtracing
3808 GDB's MIPS target configurations now handle the MIP16 16-bit
3813 GDB now includes support for overlays; if an executable has been
3814 linked such that multiple sections are based at the same address, GDB
3815 will decide which section to use for symbolic info. You can choose to
3816 control the decision manually, using overlay commands, or implement
3817 additional target-side support and use "overlay load-target" to bring
3818 in the overlay mapping. Do "help overlay" for more detail.
3822 The command "info symbol <address>" displays information about
3823 the symbol at the specified address.
3827 The standard remote protocol now includes an extension that allows
3828 asynchronous collection and display of trace data. This requires
3829 extensive support in the target-side debugging stub. Tracing mode
3830 includes a new interaction mode in GDB and new commands: see the
3831 file tracepoint.c for more details.
3835 Configurations for embedded MIPS now include a simulator contributed
3836 by Cygnus Solutions. The simulator supports the instruction sets
3837 of most MIPS variants.
3841 Sparc configurations may now include the ERC32 simulator contributed
3842 by the European Space Agency. The simulator is not built into
3843 Sparc targets by default; configure with --enable-sim to include it.
3847 For target configurations that may include multiple variants of a
3848 basic architecture (such as MIPS and SH), you may now set the
3849 architecture explicitly. "set arch" sets, "info arch" lists
3850 the possible architectures.
3852 *** Changes in GDB-4.16:
3854 * New native configurations
3856 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3857 M68K NetBSD m68k-*-netbsd*
3858 PowerPC AIX 4.x powerpc-*-aix*
3859 PowerPC MacOS powerpc-*-macos*
3860 PowerPC Windows NT powerpcle-*-cygwin32
3861 RS/6000 AIX 4.x rs6000-*-aix4*
3865 ARM with RDP protocol arm-*-*
3866 I960 with MON960 i960-*-coff
3867 MIPS VxWorks mips*-*-vxworks*
3868 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3869 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3871 Matra Sparclet sparclet-*-*
3875 The powerpc-eabi configuration now includes the PSIM simulator,
3876 contributed by Andrew Cagney, with assistance from Mike Meissner.
3877 PSIM is a very elaborate model of the PowerPC, including not only
3878 basic instruction set execution, but also details of execution unit
3879 performance and I/O hardware. See sim/ppc/README for more details.
3883 GDB now works with Solaris 2.5.
3885 * Windows 95/NT native
3887 GDB will now work as a native debugger on Windows 95 and Windows NT.
3888 To build it from source, you must use the "gnu-win32" environment,
3889 which uses a DLL to emulate enough of Unix to run the GNU tools.
3890 Further information, binaries, and sources are available at
3891 ftp.cygnus.com, under pub/gnu-win32.
3893 * dont-repeat command
3895 If a user-defined command includes the command `dont-repeat', then the
3896 command will not be repeated if the user just types return. This is
3897 useful if the command is time-consuming to run, so that accidental
3898 extra keystrokes don't run the same command many times.
3900 * Send break instead of ^C
3902 The standard remote protocol now includes an option to send a break
3903 rather than a ^C to the target in order to interrupt it. By default,
3904 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3906 * Remote protocol timeout
3908 The standard remote protocol includes a new variable `remotetimeout'
3909 that allows you to set the number of seconds before GDB gives up trying
3910 to read from the target. The default value is 2.
3912 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3914 By default GDB will automatically keep track of objects as they are
3915 loaded and unloaded by the dynamic linker. By using the command `set
3916 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3917 when shared library events occur, thus allowing you to set breakpoints
3918 in shared libraries which are explicitly loaded by the inferior.
3920 Note this feature does not work on hpux8. On hpux9 you must link
3921 /usr/lib/end.o into your program. This feature should work
3922 automatically on hpux10.
3924 * Irix 5.x hardware watchpoint support
3926 Irix 5 configurations now support the use of hardware watchpoints.
3928 * Mips protocol "SYN garbage limit"
3930 When debugging a Mips target using the `target mips' protocol, you
3931 may set the number of characters that GDB will ignore by setting
3932 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3933 every character. The default value is 1050.
3935 * Recording and replaying remote debug sessions
3937 If you set `remotelogfile' to the name of a file, gdb will write to it
3938 a recording of a remote debug session. This recording may then be
3939 replayed back to gdb using "gdbreplay". See gdbserver/README for
3940 details. This is useful when you have a problem with GDB while doing
3941 remote debugging; you can make a recording of the session and send it
3942 to someone else, who can then recreate the problem.
3944 * Speedups for remote debugging
3946 GDB includes speedups for downloading and stepping MIPS systems using
3947 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3948 and more efficient S-record downloading.
3950 * Memory use reductions and statistics collection
3952 GDB now uses less memory and reports statistics about memory usage.
3953 Try the `maint print statistics' command, for example.
3955 *** Changes in GDB-4.15:
3957 * Psymtabs for XCOFF
3959 The symbol reader for AIX GDB now uses partial symbol tables. This
3960 can greatly improve startup time, especially for large executables.
3962 * Remote targets use caching
3964 Remote targets now use a data cache to speed up communication with the
3965 remote side. The data cache could lead to incorrect results because
3966 it doesn't know about volatile variables, thus making it impossible to
3967 debug targets which use memory mapped I/O devices. `set remotecache
3968 off' turns the the data cache off.
3970 * Remote targets may have threads
3972 The standard remote protocol now includes support for multiple threads
3973 in the target system, using new protocol commands 'H' and 'T'. See
3974 gdb/remote.c for details.
3978 If GDB is configured with `--enable-netrom', then it will include
3979 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3980 acts as though it is a bank of ROM on the target board, but you can
3981 write into it over the network. GDB's support consists only of
3982 support for fast loading into the emulated ROM; to debug, you must use
3983 another protocol, such as standard remote protocol. The usual
3984 sequence is something like
3986 target nrom <netrom-hostname>
3988 target remote <netrom-hostname>:1235
3992 GDB now includes support for the Apple Macintosh, as a host only. It
3993 may be run as either an MPW tool or as a standalone application, and
3994 it can debug through the serial port. All the usual GDB commands are
3995 available, but to the target command, you must supply "serial" as the
3996 device type instead of "/dev/ttyXX". See mpw-README in the main
3997 directory for more information on how to build. The MPW configuration
3998 scripts */mpw-config.in support only a few targets, and only the
3999 mips-idt-ecoff target has been tested.
4003 GDB configuration now uses autoconf. This is not user-visible,
4004 but does simplify configuration and building.
4008 GDB now supports hpux10.
4010 *** Changes in GDB-4.14:
4012 * New native configurations
4014 x86 FreeBSD i[345]86-*-freebsd
4015 x86 NetBSD i[345]86-*-netbsd
4016 NS32k NetBSD ns32k-*-netbsd
4017 Sparc NetBSD sparc-*-netbsd
4021 A29K VxWorks a29k-*-vxworks
4022 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4023 CPU32 EST-300 emulator m68*-*-est*
4024 PowerPC ELF powerpc-*-elf
4027 * Alpha OSF/1 support for procfs
4029 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4030 possible to attach to running processes. As the mounting of the /proc
4031 filesystem is optional on the Alpha, GDB automatically determines
4032 the availability of /proc during startup. This can lead to problems
4033 if /proc is unmounted after GDB has been started.
4035 * Arguments to user-defined commands
4037 User commands may accept up to 10 arguments separated by whitespace.
4038 Arguments are accessed within the user command via $arg0..$arg9. A
4041 print $arg0 + $arg1 + $arg2
4043 To execute the command use:
4046 Defines the command "adder" which prints the sum of its three arguments.
4047 Note the arguments are text substitutions, so they may reference variables,
4048 use complex expressions, or even perform inferior function calls.
4050 * New `if' and `while' commands
4052 This makes it possible to write more sophisticated user-defined
4053 commands. Both commands take a single argument, which is the
4054 expression to evaluate, and must be followed by the commands to
4055 execute, one per line, if the expression is nonzero, the list being
4056 terminated by the word `end'. The `if' command list may include an
4057 `else' word, which causes the following commands to be executed only
4058 if the expression is zero.
4060 * Fortran source language mode
4062 GDB now includes partial support for Fortran 77. It will recognize
4063 Fortran programs and can evaluate a subset of Fortran expressions, but
4064 variables and functions may not be handled correctly. GDB will work
4065 with G77, but does not yet know much about symbols emitted by other
4068 * Better HPUX support
4070 Most debugging facilities now work on dynamic executables for HPPAs
4071 running hpux9 or later. You can attach to running dynamically linked
4072 processes, but by default the dynamic libraries will be read-only, so
4073 for instance you won't be able to put breakpoints in them. To change
4074 that behavior do the following before running the program:
4080 This will cause the libraries to be mapped private and read-write.
4081 To revert to the normal behavior, do this:
4087 You cannot set breakpoints or examine data in the library until after
4088 the library is loaded if the function/data symbols do not have
4091 GDB can now also read debug symbols produced by the HP C compiler on
4092 HPPAs (sorry, no C++, Fortran or 68k support).
4094 * Target byte order now dynamically selectable
4096 You can choose which byte order to use with a target system, via the
4097 commands "set endian big" and "set endian little", and you can see the
4098 current setting by using "show endian". You can also give the command
4099 "set endian auto", in which case GDB will use the byte order
4100 associated with the executable. Currently, only embedded MIPS
4101 configurations support dynamic selection of target byte order.
4103 * New DOS host serial code
4105 This version uses DPMI interrupts to handle buffered I/O, so you
4106 no longer need to run asynctsr when debugging boards connected to
4109 *** Changes in GDB-4.13:
4111 * New "complete" command
4113 This lists all the possible completions for the rest of the line, if it
4114 were to be given as a command itself. This is intended for use by emacs.
4116 * Trailing space optional in prompt
4118 "set prompt" no longer adds a space for you after the prompt you set. This
4119 allows you to set a prompt which ends in a space or one that does not.
4121 * Breakpoint hit counts
4123 "info break" now displays a count of the number of times the breakpoint
4124 has been hit. This is especially useful in conjunction with "ignore"; you
4125 can ignore a large number of breakpoint hits, look at the breakpoint info
4126 to see how many times the breakpoint was hit, then run again, ignoring one
4127 less than that number, and this will get you quickly to the last hit of
4130 * Ability to stop printing at NULL character
4132 "set print null-stop" will cause GDB to stop printing the characters of
4133 an array when the first NULL is encountered. This is useful when large
4134 arrays actually contain only short strings.
4136 * Shared library breakpoints
4138 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4139 breakpoints in shared libraries before the executable is run.
4141 * Hardware watchpoints
4143 There is a new hardware breakpoint for the watch command for sparclite
4144 targets. See gdb/sparclite/hw_breakpoint.note.
4146 Hardware watchpoints are also now supported under GNU/Linux.
4150 Annotations have been added. These are for use with graphical interfaces,
4151 and are still experimental. Currently only gdba.el uses these.
4153 * Improved Irix 5 support
4155 GDB now works properly with Irix 5.2.
4157 * Improved HPPA support
4159 GDB now works properly with the latest GCC and GAS.
4161 * New native configurations
4163 Sequent PTX4 i[34]86-sequent-ptx4
4164 HPPA running OSF/1 hppa*-*-osf*
4165 Atari TT running SVR4 m68*-*-sysv4*
4166 RS/6000 LynxOS rs6000-*-lynxos*
4170 OS/9000 i[34]86-*-os9k
4171 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4174 * Hitachi SH7000 and E7000-PC ICE support
4176 There is now support for communicating with the Hitachi E7000-PC ICE.
4177 This is available automatically when GDB is configured for the SH.
4181 As usual, a variety of small fixes and improvements, both generic
4182 and configuration-specific. See the ChangeLog for more detail.
4184 *** Changes in GDB-4.12:
4186 * Irix 5 is now supported
4190 GDB-4.12 on the HPPA has a number of changes which make it unable
4191 to debug the output from the currently released versions of GCC and
4192 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4193 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4194 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4197 *** Changes in GDB-4.11:
4199 * User visible changes:
4203 The "set remotedebug" option is now consistent between the mips remote
4204 target, remote targets using the gdb-specific protocol, UDI (AMD's
4205 debug protocol for the 29k) and the 88k bug monitor. It is now an
4206 integer specifying a debug level (normally 0 or 1, but 2 means more
4207 debugging info for the mips target).
4209 * DEC Alpha native support
4211 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4212 debug info, but GDB works fairly well with the DEC compiler and should
4213 work with a future GCC release. See the README file for a few
4214 Alpha-specific notes.
4216 * Preliminary thread implementation
4218 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4220 * LynxOS native and target support for 386
4222 This release has been hosted on LynxOS 2.2, and also can be configured
4223 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4226 * Improvements in C++ mangling/demangling.
4228 This release has much better g++ debugging, specifically in name
4229 mangling/demangling, virtual function calls, print virtual table,
4230 call methods, ...etc.
4232 *** Changes in GDB-4.10:
4234 * User visible changes:
4236 Remote debugging using the GDB-specific (`target remote') protocol now
4237 supports the `load' command. This is only useful if you have some
4238 other way of getting the stub to the target system, and you can put it
4239 somewhere in memory where it won't get clobbered by the download.
4241 Filename completion now works.
4243 When run under emacs mode, the "info line" command now causes the
4244 arrow to point to the line specified. Also, "info line" prints
4245 addresses in symbolic form (as well as hex).
4247 All vxworks based targets now support a user settable option, called
4248 vxworks-timeout. This option represents the number of seconds gdb
4249 should wait for responses to rpc's. You might want to use this if
4250 your vxworks target is, perhaps, a slow software simulator or happens
4251 to be on the far side of a thin network line.
4255 This release contains support for using a DEC alpha as a GDB host for
4256 cross debugging. Native alpha debugging is not supported yet.
4259 *** Changes in GDB-4.9:
4263 This is the first GDB release which is accompanied by a matching testsuite.
4264 The testsuite requires installation of dejagnu, which should be available
4265 via ftp from most sites that carry GNU software.
4269 'Cfront' style demangling has had its name changed to 'ARM' style, to
4270 emphasize that it was written from the specifications in the C++ Annotated
4271 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4272 disclaimers, it still generated too much confusion with users attempting to
4273 use gdb with AT&T cfront.
4277 GDB now uses a standard remote interface to a simulator library.
4278 So far, the library contains simulators for the Zilog Z8001/2, the
4279 Hitachi H8/300, H8/500 and Super-H.
4281 * New targets supported
4283 H8/300 simulator h8300-hitachi-hms or h8300hms
4284 H8/500 simulator h8500-hitachi-hms or h8500hms
4285 SH simulator sh-hitachi-hms or sh
4286 Z8000 simulator z8k-zilog-none or z8ksim
4287 IDT MIPS board over serial line mips-idt-ecoff
4289 Cross-debugging to GO32 targets is supported. It requires a custom
4290 version of the i386-stub.c module which is integrated with the
4291 GO32 memory extender.
4293 * New remote protocols
4295 MIPS remote debugging protocol.
4297 * New source languages supported
4299 This version includes preliminary support for Chill, a Pascal like language
4300 used by telecommunications companies. Chill support is also being integrated
4301 into the GNU compiler, but we don't know when it will be publically available.
4304 *** Changes in GDB-4.8:
4306 * HP Precision Architecture supported
4308 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4309 version of this support was available as a set of patches from the
4310 University of Utah. GDB does not support debugging of programs
4311 compiled with the HP compiler, because HP will not document their file
4312 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4313 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4315 Many problems in the preliminary version have been fixed.
4317 * Faster and better demangling
4319 We have improved template demangling and fixed numerous bugs in the GNU style
4320 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4321 character types (wchar_t) are now supported. Demangling of each symbol is now
4322 only done once, and is cached when the symbol table for a file is read in.
4323 This results in a small increase in memory usage for C programs, a moderate
4324 increase in memory usage for C++ programs, and a fantastic speedup in
4327 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4328 from the specifications in the Annotated Reference Manual, which AT&T's
4329 compiler does not actually implement.
4331 * G++ multiple inheritance compiler problem
4333 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4334 inheritance lattices was reworked to properly discover ambiguities. We
4335 recently found an example which causes this new algorithm to fail in a
4336 very subtle way, producing bad debug information for those classes.
4337 The file 'gcc.patch' (in this directory) can be applied to gcc to
4338 circumvent the problem. A future GCC release will contain a complete
4341 The previous G++ debug info problem (mentioned below for the gdb-4.7
4342 release) is fixed in gcc version 2.3.2.
4344 * Improved configure script
4346 The `configure' script will now attempt to guess your system type if
4347 you don't supply a host system type. The old scheme of supplying a
4348 host system triplet is preferable over using this. All the magic is
4349 done in the new `config.guess' script. Examine it for details.
4351 We have also brought our configure script much more in line with the FSF's
4352 version. It now supports the --with-xxx options. In particular,
4353 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4354 The resulting GDB will not be able to read arbitrary object file formats --
4355 only the format ``expected'' to be used on the configured target system.
4356 We hope to make this the default in a future release.
4358 * Documentation improvements
4360 There's new internal documentation on how to modify GDB, and how to
4361 produce clean changes to the code. We implore people to read it
4362 before submitting changes.
4364 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4365 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4366 `info' files are also provided. To build `info' files from scratch,
4367 you will need the latest `makeinfo' release, which will be available in
4368 a future texinfo-X.Y release.
4370 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4371 We're not sure exactly which versions have this problem, but it has
4372 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4373 or better. If that isn't possible, there is a patch in
4374 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4375 around this problem.
4379 GDB now supports array constants that can be used in expressions typed in by
4380 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4381 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4384 The new directory `gdb/sparclite' contains a program that demonstrates
4385 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4387 * New native hosts supported
4389 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4390 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4392 * New targets supported
4394 AMD 29k family via UDI a29k-amd-udi or udi29k
4396 * New file formats supported
4398 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4399 HPUX core files, and SCO 3.2v2 core files.
4403 Attaching to processes now works again; thanks for the many bug reports.
4405 We have also stomped on a bunch of core dumps caused by
4406 printf_filtered("%s") problems.
4408 We eliminated a copyright problem on the rpc and ptrace header files
4409 for VxWorks, which was discovered at the last minute during the 4.7
4410 release. You should now be able to build a VxWorks GDB.
4412 You can now interrupt gdb while an attached process is running. This
4413 will cause the attached process to stop, and give control back to GDB.
4415 We fixed problems caused by using too many file descriptors
4416 for reading symbols from object files and libraries. This was
4417 especially a problem for programs that used many (~100) shared
4420 The `step' command now only enters a subroutine if there is line number
4421 information for the subroutine. Otherwise it acts like the `next'
4422 command. Previously, `step' would enter subroutines if there was
4423 any debugging information about the routine. This avoids problems
4424 when using `cc -g1' on MIPS machines.
4426 * Internal improvements
4428 GDB's internal interfaces have been improved to make it easier to support
4429 debugging of multiple languages in the future.
4431 GDB now uses a common structure for symbol information internally.
4432 Minimal symbols (derived from linkage symbols in object files), partial
4433 symbols (from a quick scan of debug information), and full symbols
4434 contain a common subset of information, making it easier to write
4435 shared code that handles any of them.
4437 * New command line options
4439 We now accept --silent as an alias for --quiet.
4443 The memory-mapped-malloc library is now licensed under the GNU Library
4444 General Public License.
4446 *** Changes in GDB-4.7:
4448 * Host/native/target split
4450 GDB has had some major internal surgery to untangle the support for
4451 hosts and remote targets. Now, when you configure GDB for a remote
4452 target, it will no longer load in all of the support for debugging
4453 local programs on the host. When fully completed and tested, this will
4454 ensure that arbitrary host/target combinations are possible.
4456 The primary conceptual shift is to separate the non-portable code in
4457 GDB into three categories. Host specific code is required any time GDB
4458 is compiled on that host, regardless of the target. Target specific
4459 code relates to the peculiarities of the target, but can be compiled on
4460 any host. Native specific code is everything else: it can only be
4461 built when the host and target are the same system. Child process
4462 handling and core file support are two common `native' examples.
4464 GDB's use of /proc for controlling Unix child processes is now cleaner.
4465 It has been split out into a single module under the `target_ops' vector,
4466 plus two native-dependent functions for each system that uses /proc.
4468 * New hosts supported
4470 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4471 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4472 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4474 * New targets supported
4476 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4477 68030 and CPU32 m68030-*-*, m68332-*-*
4479 * New native hosts supported
4481 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4482 (386bsd is not well tested yet)
4483 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4485 * New file formats supported
4487 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4488 supports reading of `a.out.adobe' object files, which are an a.out
4489 format extended with minimal information about multiple sections.
4493 `show copying' is the same as the old `info copying'.
4494 `show warranty' is the same as `info warrantee'.
4495 These were renamed for consistency. The old commands continue to work.
4497 `info handle' is a new alias for `info signals'.
4499 You can now define pre-command hooks, which attach arbitrary command
4500 scripts to any command. The commands in the hook will be executed
4501 prior to the user's command. You can also create a hook which will be
4502 executed whenever the program stops. See gdb.texinfo.
4506 We now deal with Cfront style name mangling, and can even extract type
4507 info from mangled symbols. GDB can automatically figure out which
4508 symbol mangling style your C++ compiler uses.
4510 Calling of methods and virtual functions has been improved as well.
4514 The crash that occured when debugging Sun Ansi-C compiled binaries is
4515 fixed. This was due to mishandling of the extra N_SO stabs output
4518 We also finally got Ultrix 4.2 running in house, and fixed core file
4519 support, with help from a dozen people on the net.
4521 John M. Farrell discovered that the reason that single-stepping was so
4522 slow on all of the Mips based platforms (primarily SGI and DEC) was
4523 that we were trying to demangle and lookup a symbol used for internal
4524 purposes on every instruction that was being stepped through. Changing
4525 the name of that symbol so that it couldn't be mistaken for a C++
4526 mangled symbol sped things up a great deal.
4528 Rich Pixley sped up symbol lookups in general by getting much smarter
4529 about when C++ symbol mangling is necessary. This should make symbol
4530 completion (TAB on the command line) much faster. It's not as fast as
4531 we'd like, but it's significantly faster than gdb-4.6.
4535 A new user controllable variable 'call_scratch_address' can
4536 specify the location of a scratch area to be used when GDB
4537 calls a function in the target. This is necessary because the
4538 usual method of putting the scratch area on the stack does not work
4539 in systems that have separate instruction and data spaces.
4541 We integrated changes to support the 29k UDI (Universal Debugger
4542 Interface), but discovered at the last minute that we didn't have all
4543 of the appropriate copyright paperwork. We are working with AMD to
4544 resolve this, and hope to have it available soon.
4548 We have sped up the remote serial line protocol, especially for targets
4549 with lots of registers. It now supports a new `expedited status' ('T')
4550 message which can be used in place of the existing 'S' status message.
4551 This allows the remote stub to send only the registers that GDB
4552 needs to make a quick decision about single-stepping or conditional
4553 breakpoints, eliminating the need to fetch the entire register set for
4554 each instruction being stepped through.
4556 The GDB remote serial protocol now implements a write-through cache for
4557 registers, only re-reading the registers if the target has run.
4559 There is also a new remote serial stub for SPARC processors. You can
4560 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4561 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4562 processor with a serial port.
4566 Configure.in files have become much easier to read and modify. A new
4567 `table driven' format makes it more obvious what configurations are
4568 supported, and what files each one uses.
4572 There is a new opcodes library which will eventually contain all of the
4573 disassembly routines and opcode tables. At present, it only contains
4574 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4575 disassembler (binutils/objdump) to share these routines.
4577 The libiberty library is now copylefted under the GNU Library General
4578 Public License. This allows more liberal use, and was done so libg++
4579 can use it. This makes no difference to GDB, since the Library License
4580 grants all the rights from the General Public License.
4584 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4585 reference to the stabs symbol info used by the debugger. It is (as far
4586 as we know) the only published document on this fascinating topic. We
4587 encourage you to read it, compare it to the stabs information on your
4588 system, and send improvements on the document in general (to
4589 bug-gdb@prep.ai.mit.edu).
4591 And, of course, many bugs have been fixed.
4594 *** Changes in GDB-4.6:
4596 * Better support for C++ function names
4598 GDB now accepts as input the "demangled form" of C++ overloaded function
4599 names and member function names, and can do command completion on such names
4600 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4601 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4602 Make use of command completion, it is your friend.
4604 GDB also now accepts a variety of C++ mangled symbol formats. They are
4605 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4606 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4607 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4608 for the list of formats.
4610 * G++ symbol mangling problem
4612 Recent versions of gcc have a bug in how they emit debugging information for
4613 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4614 directory) can be applied to gcc to fix the problem. Alternatively, if you
4615 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4616 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4617 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4620 * New 'maintenance' command
4622 All of the commands related to hacking GDB internals have been moved out of
4623 the main command set, and now live behind the 'maintenance' command. This
4624 can also be abbreviated as 'mt'. The following changes were made:
4626 dump-me -> maintenance dump-me
4627 info all-breakpoints -> maintenance info breakpoints
4628 printmsyms -> maintenance print msyms
4629 printobjfiles -> maintenance print objfiles
4630 printpsyms -> maintenance print psymbols
4631 printsyms -> maintenance print symbols
4633 The following commands are new:
4635 maintenance demangle Call internal GDB demangler routine to
4636 demangle a C++ link name and prints the result.
4637 maintenance print type Print a type chain for a given symbol
4639 * Change to .gdbinit file processing
4641 We now read the $HOME/.gdbinit file before processing the argv arguments
4642 (e.g. reading symbol files or core files). This allows global parameters to
4643 be set, which will apply during the symbol reading. The ./.gdbinit is still
4644 read after argv processing.
4646 * New hosts supported
4648 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4650 GNU/Linux support i386-unknown-linux or linux
4652 We are also including code to support the HP/PA running BSD and HPUX. This
4653 is almost guaranteed not to work, as we didn't have time to test or build it
4654 for this release. We are including it so that the more adventurous (or
4655 masochistic) of you can play with it. We also had major problems with the
4656 fact that the compiler that we got from HP doesn't support the -g option.
4659 * New targets supported
4661 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4663 * More smarts about finding #include files
4665 GDB now remembers the compilation directory for all include files, and for
4666 all files from which C is generated (like yacc and lex sources). This
4667 greatly improves GDB's ability to find yacc/lex sources, and include files,
4668 especially if you are debugging your program from a directory different from
4669 the one that contains your sources.
4671 We also fixed a bug which caused difficulty with listing and setting
4672 breakpoints in include files which contain C code. (In the past, you had to
4673 try twice in order to list an include file that you hadn't looked at before.)
4675 * Interesting infernals change
4677 GDB now deals with arbitrary numbers of sections, where the symbols for each
4678 section must be relocated relative to that section's landing place in the
4679 target's address space. This work was needed to support ELF with embedded
4680 stabs used by Solaris-2.0.
4682 * Bug fixes (of course!)
4684 There have been loads of fixes for the following things:
4685 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4686 i960, stabs, DOS(GO32), procfs, etc...
4688 See the ChangeLog for details.
4690 *** Changes in GDB-4.5:
4692 * New machines supported (host and target)
4694 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4696 SGI Irix-4.x mips-sgi-irix4 or iris4
4698 * New malloc package
4700 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4701 Mmalloc is capable of handling mutiple heaps of memory. It is also
4702 capable of saving a heap to a file, and then mapping it back in later.
4703 This can be used to greatly speedup the startup of GDB by using a
4704 pre-parsed symbol table which lives in a mmalloc managed heap. For
4705 more details, please read mmalloc/mmalloc.texi.
4709 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4710 'help info proc' for details.
4712 * MIPS ecoff symbol table format
4714 The code that reads MIPS symbol table format is now supported on all hosts.
4715 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4718 * File name changes for MS-DOS
4720 Many files in the config directories have been renamed to make it easier to
4721 support GDB on MS-DOSe systems (which have very restrictive file name
4722 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4723 environment) is close to working but has some remaining problems. Note
4724 that debugging of DOS programs is not supported, due to limitations
4725 in the ``operating system'', but it can be used to host cross-debugging.
4727 * Cross byte order fixes
4729 Many fixes have been made to support cross debugging of Sparc and MIPS
4730 targets from hosts whose byte order differs.
4732 * New -mapped and -readnow options
4734 If memory-mapped files are available on your system through the 'mmap'
4735 system call, you can use the -mapped option on the `file' or
4736 `symbol-file' commands to cause GDB to write the symbols from your
4737 program into a reusable file. If the program you are debugging is
4738 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4739 Future GDB debugging sessions will notice the presence of this file,
4740 and will quickly map in symbol information from it, rather than reading
4741 the symbol table from the executable program. Using the '-mapped'
4742 option in a GDB `file' or `symbol-file' command has the same effect as
4743 starting GDB with the '-mapped' command-line option.
4745 You can cause GDB to read the entire symbol table immediately by using
4746 the '-readnow' option with any of the commands that load symbol table
4747 information (or on the GDB command line). This makes the command
4748 slower, but makes future operations faster.
4750 The -mapped and -readnow options are typically combined in order to
4751 build a `fred.syms' file that contains complete symbol information.
4752 A simple GDB invocation to do nothing but build a `.syms' file for future
4755 gdb -batch -nx -mapped -readnow programname
4757 The `.syms' file is specific to the host machine on which GDB is run.
4758 It holds an exact image of GDB's internal symbol table. It cannot be
4759 shared across multiple host platforms.
4761 * longjmp() handling
4763 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4764 siglongjmp() without losing control. This feature has not yet been ported to
4765 all systems. It currently works on many 386 platforms, all MIPS-based
4766 platforms (SGI, DECstation, etc), and Sun3/4.
4770 Preliminary work has been put in to support the new Solaris OS from Sun. At
4771 this time, it can control and debug processes, but it is not capable of
4776 As always, many many bug fixes. The major areas were with g++, and mipsread.
4777 People using the MIPS-based platforms should experience fewer mysterious
4778 crashes and trashed symbol tables.
4780 *** Changes in GDB-4.4:
4782 * New machines supported (host and target)
4784 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4786 BSD Reno on Vax vax-dec-bsd
4787 Ultrix on Vax vax-dec-ultrix
4789 * New machines supported (target)
4791 AMD 29000 embedded, using EBMON a29k-none-none
4795 GDB continues to improve its handling of C++. `References' work better.
4796 The demangler has also been improved, and now deals with symbols mangled as
4797 per the Annotated C++ Reference Guide.
4799 GDB also now handles `stabs' symbol information embedded in MIPS
4800 `ecoff' symbol tables. Since the ecoff format was not easily
4801 extensible to handle new languages such as C++, this appeared to be a
4802 good way to put C++ debugging info into MIPS binaries. This option
4803 will be supported in the GNU C compiler, version 2, when it is
4806 * New features for SVR4
4808 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4809 shared libraries. Debugging dynamically linked programs should present
4810 only minor differences from debugging statically linked programs.
4812 The `info proc' command will print out information about any process
4813 on an SVR4 system (including the one you are debugging). At the moment,
4814 it prints the address mappings of the process.
4816 If you bring up GDB on another SVR4 system, please send mail to
4817 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4819 * Better dynamic linking support in SunOS
4821 Reading symbols from shared libraries which contain debugging symbols
4822 now works properly. However, there remain issues such as automatic
4823 skipping of `transfer vector' code during function calls, which
4824 make it harder to debug code in a shared library, than to debug the
4825 same code linked statically.
4829 GDB is now using the latest `getopt' routines from the FSF. This
4830 version accepts the -- prefix for options with long names. GDB will
4831 continue to accept the old forms (-option and +option) as well.
4832 Various single letter abbreviations for options have been explicity
4833 added to the option table so that they won't get overshadowed in the
4834 future by other options that begin with the same letter.
4838 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4839 Many assorted bugs have been handled. Many more remain to be handled.
4840 See the various ChangeLog files (primarily in gdb and bfd) for details.
4843 *** Changes in GDB-4.3:
4845 * New machines supported (host and target)
4847 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4848 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4849 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4851 * Almost SCO Unix support
4853 We had hoped to support:
4854 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4855 (except for core file support), but we discovered very late in the release
4856 that it has problems with process groups that render gdb unusable. Sorry
4857 about that. I encourage people to fix it and post the fixes.
4859 * Preliminary ELF and DWARF support
4861 GDB can read ELF object files on System V Release 4, and can handle
4862 debugging records for C, in DWARF format, in ELF files. This support
4863 is preliminary. If you bring up GDB on another SVR4 system, please
4864 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4869 GDB now uses the latest `readline' library. One user-visible change
4870 is that two tabs will list possible command completions, which previously
4871 required typing M-? (meta-question mark, or ESC ?).
4875 The `stepi' bug that many of you noticed has been squashed.
4876 Many bugs in C++ have been handled. Many more remain to be handled.
4877 See the various ChangeLog files (primarily in gdb and bfd) for details.
4879 * State of the MIPS world (in case you wondered):
4881 GDB can understand the symbol tables emitted by the compilers
4882 supplied by most vendors of MIPS-based machines, including DEC. These
4883 symbol tables are in a format that essentially nobody else uses.
4885 Some versions of gcc come with an assembler post-processor called
4886 mips-tfile. This program is required if you want to do source-level
4887 debugging of gcc-compiled programs. I believe FSF does not ship
4888 mips-tfile with gcc version 1, but it will eventually come with gcc
4891 Debugging of g++ output remains a problem. g++ version 1.xx does not
4892 really support it at all. (If you're lucky, you should be able to get
4893 line numbers and stack traces to work, but no parameters or local
4894 variables.) With some work it should be possible to improve the
4897 When gcc version 2 is released, you will have somewhat better luck.
4898 However, even then you will get confusing results for inheritance and
4901 We will eventually provide full debugging of g++ output on
4902 DECstations. This will probably involve some kind of stabs-in-ecoff
4903 encapulation, but the details have not been worked out yet.
4906 *** Changes in GDB-4.2:
4908 * Improved configuration
4910 Only one copy of `configure' exists now, and it is not self-modifying.
4911 Porting BFD is simpler.
4915 The `step' and `next' commands now only stop at the first instruction
4916 of a source line. This prevents the multiple stops that used to occur
4917 in switch statements, for-loops, etc. `Step' continues to stop if a
4918 function that has debugging information is called within the line.
4922 Lots of small bugs fixed. More remain.
4924 * New host supported (not target)
4926 Intel 386 PC clone running Mach i386-none-mach
4929 *** Changes in GDB-4.1:
4931 * Multiple source language support
4933 GDB now has internal scaffolding to handle several source languages.
4934 It determines the type of each source file from its filename extension,
4935 and will switch expression parsing and number formatting to match the
4936 language of the function in the currently selected stack frame.
4937 You can also specifically set the language to be used, with
4938 `set language c' or `set language modula-2'.
4942 GDB now has preliminary support for the GNU Modula-2 compiler,
4943 currently under development at the State University of New York at
4944 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4945 continue through the fall of 1991 and into 1992.
4947 Other Modula-2 compilers are currently not supported, and attempting to
4948 debug programs compiled with them will likely result in an error as the
4949 symbol table is read. Feel free to work on it, though!
4951 There are hooks in GDB for strict type checking and range checking,
4952 in the `Modula-2 philosophy', but they do not currently work.
4956 GDB can now write to executable and core files (e.g. patch
4957 a variable's value). You must turn this switch on, specify
4958 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4959 by assigning a new value to a variable. Modifications take
4962 * Automatic SunOS shared library reading
4964 When you run your program, GDB automatically determines where its
4965 shared libraries (if any) have been loaded, and reads their symbols.
4966 The `share' command is no longer needed. This also works when
4967 examining core files.
4971 You can specify the number of lines that the `list' command shows.
4974 * New machines supported (host and target)
4976 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4977 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4978 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4980 * New hosts supported (not targets)
4982 IBM RT/PC: romp-ibm-aix or rtpc
4984 * New targets supported (not hosts)
4986 AMD 29000 embedded with COFF a29k-none-coff
4987 AMD 29000 embedded with a.out a29k-none-aout
4988 Ultracomputer remote kernel debug a29k-nyu-kern
4990 * New remote interfaces
4996 *** Changes in GDB-4.0:
5000 Wide output is wrapped at good places to make the output more readable.
5002 Gdb now supports cross-debugging from a host machine of one type to a
5003 target machine of another type. Communication with the target system
5004 is over serial lines. The ``target'' command handles connecting to the
5005 remote system; the ``load'' command will download a program into the
5006 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5007 also supports debugging of realtime processes running under VxWorks,
5008 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5009 stub on the target system.
5011 New CPUs supported include the AMD 29000 and Intel 960.
5013 GDB now reads object files and symbol tables via a ``binary file''
5014 library, which allows a single copy of GDB to debug programs of multiple
5015 object file types such as a.out and coff.
5017 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5018 refcard.dvi and refcard.ps are available to format it).
5021 * Control-Variable user interface simplified
5023 All variables that control the operation of the debugger can be set
5024 by the ``set'' command, and displayed by the ``show'' command.
5026 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5027 ``Show prompt'' produces the response:
5028 Gdb's prompt is new-gdb=>.
5030 What follows are the NEW set commands. The command ``help set'' will
5031 print a complete list of old and new set commands. ``help set FOO''
5032 will give a longer description of the variable FOO. ``show'' will show
5033 all of the variable descriptions and their current settings.
5035 confirm on/off: Enables warning questions for operations that are
5036 hard to recover from, e.g. rerunning the program while
5037 it is already running. Default is ON.
5039 editing on/off: Enables EMACS style command line editing
5040 of input. Previous lines can be recalled with
5041 control-P, the current line can be edited with control-B,
5042 you can search for commands with control-R, etc.
5045 history filename NAME: NAME is where the gdb command history
5046 will be stored. The default is .gdb_history,
5047 or the value of the environment variable
5050 history size N: The size, in commands, of the command history. The
5051 default is 256, or the value of the environment variable
5054 history save on/off: If this value is set to ON, the history file will
5055 be saved after exiting gdb. If set to OFF, the
5056 file will not be saved. The default is OFF.
5058 history expansion on/off: If this value is set to ON, then csh-like
5059 history expansion will be performed on
5060 command line input. The default is OFF.
5062 radix N: Sets the default radix for input and output. It can be set
5063 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5064 in the current radix, so "set radix 10" is always a no-op.
5066 height N: This integer value is the number of lines on a page. Default
5067 is 24, the current `stty rows'' setting, or the ``li#''
5068 setting from the termcap entry matching the environment
5071 width N: This integer value is the number of characters on a line.
5072 Default is 80, the current `stty cols'' setting, or the ``co#''
5073 setting from the termcap entry matching the environment
5076 Note: ``set screensize'' is obsolete. Use ``set height'' and
5077 ``set width'' instead.
5079 print address on/off: Print memory addresses in various command displays,
5080 such as stack traces and structure values. Gdb looks
5081 more ``symbolic'' if you turn this off; it looks more
5082 ``machine level'' with it on. Default is ON.
5084 print array on/off: Prettyprint arrays. New convenient format! Default
5087 print demangle on/off: Print C++ symbols in "source" form if on,
5090 print asm-demangle on/off: Same, for assembler level printouts
5093 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5096 * Support for Epoch Environment.
5098 The epoch environment is a version of Emacs v18 with windowing. One
5099 new command, ``inspect'', is identical to ``print'', except that if you
5100 are running in the epoch environment, the value is printed in its own
5104 * Support for Shared Libraries
5106 GDB can now debug programs and core files that use SunOS shared libraries.
5107 Symbols from a shared library cannot be referenced
5108 before the shared library has been linked with the program (this
5109 happens after you type ``run'' and before the function main() is entered).
5110 At any time after this linking (including when examining core files
5111 from dynamically linked programs), gdb reads the symbols from each
5112 shared library when you type the ``sharedlibrary'' command.
5113 It can be abbreviated ``share''.
5115 sharedlibrary REGEXP: Load shared object library symbols for files
5116 matching a unix regular expression. No argument
5117 indicates to load symbols for all shared libraries.
5119 info sharedlibrary: Status of loaded shared libraries.
5124 A watchpoint stops execution of a program whenever the value of an
5125 expression changes. Checking for this slows down execution
5126 tremendously whenever you are in the scope of the expression, but is
5127 quite useful for catching tough ``bit-spreader'' or pointer misuse
5128 problems. Some machines such as the 386 have hardware for doing this
5129 more quickly, and future versions of gdb will use this hardware.
5131 watch EXP: Set a watchpoint (breakpoint) for an expression.
5133 info watchpoints: Information about your watchpoints.
5135 delete N: Deletes watchpoint number N (same as breakpoints).
5136 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5137 enable N: Re-enables watchpoint number N (same as breakpoints).
5140 * C++ multiple inheritance
5142 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5145 * C++ exception handling
5147 Gdb now supports limited C++ exception handling. Besides the existing
5148 ability to breakpoint on an exception handler, gdb can breakpoint on
5149 the raising of an exception (before the stack is peeled back to the
5152 catch FOO: If there is a FOO exception handler in the dynamic scope,
5153 set a breakpoint to catch exceptions which may be raised there.
5154 Multiple exceptions (``catch foo bar baz'') may be caught.
5156 info catch: Lists all exceptions which may be caught in the
5157 current stack frame.
5160 * Minor command changes
5162 The command ``call func (arg, arg, ...)'' now acts like the print
5163 command, except it does not print or save a value if the function's result
5164 is void. This is similar to dbx usage.
5166 The ``up'' and ``down'' commands now always print the frame they end up
5167 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5168 frames without printing.
5170 * New directory command
5172 'dir' now adds directories to the FRONT of the source search path.
5173 The path starts off empty. Source files that contain debug information
5174 about the directory in which they were compiled can be found even
5175 with an empty path; Sun CC and GCC include this information. If GDB can't
5176 find your source file in the current directory, type "dir .".
5178 * Configuring GDB for compilation
5180 For normal use, type ``./configure host''. See README or gdb.texinfo
5183 GDB now handles cross debugging. If you are remotely debugging between
5184 two different machines, type ``./configure host -target=targ''.
5185 Host is the machine where GDB will run; targ is the machine
5186 where the program that you are debugging will run.