1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.5
8 Lynx 178 PowerPC powerpc-*-lynx*178
10 * If the configured location of system.gdbinit file (as given by the
11 --with-system-gdbinit option at configure time) is in the
12 data-directory (as specified by --with-gdb-datadir at configure
13 time) or in one of its subdirectories, then GDB will look for the
14 system-wide init file in the directory specified by the
15 --data-directory command-line option.
17 * New command line options:
19 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
20 other initialization files, unlike -nx which disables all of them.
22 * Removed command line options
24 -epoch This was used by the gdb mode in Epoch, an ancient fork of
27 * The 'ptype' and 'whatis' commands now accept an argument to control
30 * 'info proc' now works on some core files.
34 ** Vectors can be created with gdb.Type.vector.
36 ** Python's atexit.register now works in GDB.
38 ** Types can be pretty-printed via a Python API.
40 ** Python 3 is now supported (in addition to Python 2.4 or later)
42 ** New class gdb.Architecture exposes GDB's internal representation
43 of architecture in the Python API.
45 ** New method Frame.architecture returns the gdb.Architecture object
46 corresponding to the frame's architecture.
48 * New Python-based convenience functions:
50 ** $_memeq(buf1, buf2, length)
51 ** $_streq(str1, str2)
53 ** $_regex(str, regex)
55 * The 'cd' command now defaults to using '~' (the home directory) if not
58 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
59 default for GCC since November 2000.
61 * The command 'forward-search' can now be abbreviated as 'fo'.
63 * The command 'info tracepoints' can now display 'installed on target'
64 or 'not installed on target' for each non-pending location of tracepoint.
66 * New configure options
68 --enable-libmcheck/--disable-libmcheck
69 By default, development versions are built with -lmcheck on hosts
70 that support it, in order to help track memory corruption issues.
71 Release versions, on the other hand, are built without -lmcheck
72 by default. The --enable-libmcheck/--disable-libmcheck configure
73 options allow the user to override that default.
75 * New commands (for set/show, see "New options" below)
78 Catch signals. This is similar to "handle", but allows commands and
79 conditions to be attached.
82 List the BFDs known to GDB.
84 python-interactive [command]
86 Start a Python interactive prompt, or evaluate the optional command
87 and print the result of expressions.
90 "py" is a new alias for "python".
92 enable type-printer [name]...
93 disable type-printer [name]...
94 Enable or disable type printers.
96 set debug notification
97 show debug notification
98 Control display of debugging info for async remote notification.
102 ** For the Renesas Super-H architecture, the "regs" command has been removed
103 (has been deprecated in GDB 7.5), and "info all-registers" should be used
108 set print type methods (on|off)
109 show print type methods
110 Control whether method declarations are displayed by "ptype".
111 The default is to show them.
113 set print type typedefs (on|off)
114 show print type typedefs
115 Control whether typedef definitions are displayed by "ptype".
116 The default is to show them.
120 ** Command parameter changes are now notified using new async record
121 "=cmd-param-changed".
122 ** Trace frame changes caused by command "tfind" are now notified using
123 new async record "=traceframe-changed".
124 ** The creation and deletion of trace state variables are now notified
125 using new async records "=tsv-created" and "=tsv-deleted".
126 ** The start and stop of process record are now notified using new
127 async record "=record-started" and "=record-stopped".
128 ** Memory changes are now notified using new async record
130 ** The data-disassemble command response will include a "fullname" field
131 containing the absolute file name when GDB can determine it and source
133 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
134 command, to allow pattern filling of memory areas.
135 ** New commands "-catch-load"/"-catch-unload" added for intercepting
136 library load/unload events.
137 ** The response to breakpoint commands and breakpoint async records
138 includes an "installed" field containing a boolean state about each
139 non-pending tracepoint location is whether installed on target or not.
141 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
142 You must have the LZMA library available when configuring GDB for this
143 feature to be enabled. For more information, see:
144 http://fedoraproject.org/wiki/Features/MiniDebugInfo
146 *** Changes in GDB 7.5
148 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
149 for more x32 ABI info.
151 * GDB now supports access to MIPS DSP registers on Linux targets.
153 * GDB now supports debugging microMIPS binaries.
155 * The "info os" command on GNU/Linux can now display information on
156 several new classes of objects managed by the operating system:
157 "info os procgroups" lists process groups
158 "info os files" lists file descriptors
159 "info os sockets" lists internet-domain sockets
160 "info os shm" lists shared-memory regions
161 "info os semaphores" lists semaphores
162 "info os msg" lists message queues
163 "info os modules" lists loaded kernel modules
165 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
166 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
167 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
168 options and inspect the probe arguments using the new $_probe_arg family
169 of convenience variables. You can obtain more information about SystemTap
170 in <http://sourceware.org/systemtap/>.
172 * GDB now supports reversible debugging on ARM, it allows you to
173 debug basic ARM and THUMB instructions, and provides
174 record/replay support.
176 * The option "symbol-reloading" has been deleted as it is no longer used.
180 ** GDB commands implemented in Python can now be put in command class
183 ** The "maint set python print-stack on|off" is now deleted.
185 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
186 apply "flag enum"-style pretty-printing to any enum.
188 ** gdb.lookup_symbol can now work when there is no current frame.
190 ** gdb.Symbol now has a 'line' attribute, holding the line number in
191 the source at which the symbol was defined.
193 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
194 method 'value'. The former indicates whether the symbol needs a
195 frame in order to compute its value, and the latter computes the
198 ** A new method 'referenced_value' on gdb.Value objects which can
199 dereference pointer as well as C++ reference values.
201 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
202 which return the global and static blocks (as gdb.Block objects),
203 of the underlying symbol table, respectively.
205 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
206 object associated with a PC value.
208 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
209 of the address range occupied by code for the current source line.
211 * Go language support.
212 GDB now supports debugging programs written in the Go programming
215 * GDBserver now supports stdio connections.
216 E.g. (gdb) target remote | ssh myhost gdbserver - hello
218 * The binary "gdbtui" can no longer be built or installed.
219 Use "gdb -tui" instead.
221 * GDB will now print "flag" enums specially. A flag enum is one where
222 all the enumerator values have no bits in common when pairwise
223 "and"ed. When printing a value whose type is a flag enum, GDB will
224 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
225 (gdb) print (enum E) 3
228 * The filename part of a linespec will now match trailing components
229 of a source file name. For example, "break gcc/expr.c:1000" will
230 now set a breakpoint in build/gcc/expr.c, but not
233 * The "info proc" and "generate-core-file" commands will now also
234 work on remote targets connected to GDBserver on Linux.
236 * The command "info catch" has been removed. It has been disabled
239 * The "catch exception" and "catch assert" commands now accept
240 a condition at the end of the command, much like the "break"
241 command does. For instance:
243 (gdb) catch exception Constraint_Error if Barrier = True
245 Previously, it was possible to add a condition to such catchpoints,
246 but it had to be done as a second step, after the catchpoint had been
247 created, using the "condition" command.
249 * The "info static-tracepoint-marker" command will now also work on
250 native Linux targets with in-process agent.
252 * GDB can now set breakpoints on inlined functions.
254 * The .gdb_index section has been updated to include symbols for
255 inlined functions. GDB will ignore older .gdb_index sections by
256 default, which could cause symbol files to be loaded more slowly
257 until their .gdb_index sections can be recreated. The new command
258 "set use-deprecated-index-sections on" will cause GDB to use any older
259 .gdb_index sections it finds. This will restore performance, but the
260 ability to set breakpoints on inlined functions will be lost in symbol
261 files with older .gdb_index sections.
263 The .gdb_index section has also been updated to record more information
264 about each symbol. This speeds up the "info variables", "info functions"
265 and "info types" commands when used with programs having the .gdb_index
266 section, as well as speeding up debugging with shared libraries using
267 the .gdb_index section.
269 * Ada support for GDB/MI Variable Objects has been added.
271 * GDB can now support 'breakpoint always-inserted mode' in 'record'
276 ** New command -info-os is the MI equivalent of "info os".
278 ** Output logs ("set logging" and related) now include MI output.
282 ** "set use-deprecated-index-sections on|off"
283 "show use-deprecated-index-sections on|off"
284 Controls the use of deprecated .gdb_index sections.
286 ** "catch load" and "catch unload" can be used to stop when a shared
287 library is loaded or unloaded, respectively.
289 ** "enable count" can be used to auto-disable a breakpoint after
292 ** "info vtbl" can be used to show the virtual method tables for
293 C++ and Java objects.
295 ** "explore" and its sub commands "explore value" and "explore type"
296 can be used to reccursively explore values and types of
297 expressions. These commands are available only if GDB is
298 configured with '--with-python'.
300 ** "info auto-load" shows status of all kinds of auto-loaded files,
301 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
302 sequences of commands files, "info auto-load python-scripts"
303 shows status of auto-loading Python script files,
304 "info auto-load local-gdbinit" shows status of loading init file
305 (.gdbinit) from current directory and "info auto-load libthread-db" shows
306 status of inferior specific thread debugging shared library loading.
308 ** "info auto-load-scripts", "set auto-load-scripts on|off"
309 and "show auto-load-scripts" commands have been deprecated, use their
310 "info auto-load python-scripts", "set auto-load python-scripts on|off"
311 and "show auto-load python-scripts" counterparts instead.
313 ** "dprintf location,format,args..." creates a dynamic printf, which
314 is basically a breakpoint that does a printf and immediately
315 resumes your program's execution, so it is like a printf that you
316 can insert dynamically at runtime instead of at compiletime.
318 ** "set print symbol"
320 Controls whether GDB attempts to display the symbol, if any,
321 corresponding to addresses it prints. This defaults to "on", but
322 you can set it to "off" to restore GDB's previous behavior.
324 * Deprecated commands
326 ** For the Renesas Super-H architecture, the "regs" command has been
327 deprecated, and "info all-registers" should be used instead.
331 Renesas RL78 rl78-*-elf
332 HP OpenVMS ia64 ia64-hp-openvms*
334 * GDBserver supports evaluation of breakpoint conditions. When
335 support is advertised by GDBserver, GDB may be told to send the
336 breakpoint conditions in bytecode form to GDBserver. GDBserver
337 will only report the breakpoint trigger to GDB when its condition
343 show mips compression
344 Select the compressed ISA encoding used in functions that have no symbol
345 information available. The encoding can be set to either of:
348 and is updated automatically from ELF file flags if available.
350 set breakpoint condition-evaluation
351 show breakpoint condition-evaluation
352 Control whether breakpoint conditions are evaluated by GDB ("host") or by
353 GDBserver ("target"). Default option "auto" chooses the most efficient
355 This option can improve debugger efficiency depending on the speed of the
359 Disable auto-loading globally.
362 Show auto-loading setting of all kinds of auto-loaded files.
364 set auto-load gdb-scripts on|off
365 show auto-load gdb-scripts
366 Control auto-loading of GDB canned sequences of commands files.
368 set auto-load python-scripts on|off
369 show auto-load python-scripts
370 Control auto-loading of Python script files.
372 set auto-load local-gdbinit on|off
373 show auto-load local-gdbinit
374 Control loading of init file (.gdbinit) from current directory.
376 set auto-load libthread-db on|off
377 show auto-load libthread-db
378 Control auto-loading of inferior specific thread debugging shared library.
380 set auto-load scripts-directory <dir1>[:<dir2>...]
381 show auto-load scripts-directory
382 Set a list of directories from which to load auto-loaded scripts.
383 Automatically loaded Python scripts and GDB scripts are located in one
384 of the directories listed by this option.
385 The delimiter (':' above) may differ according to the host platform.
387 set auto-load safe-path <dir1>[:<dir2>...]
388 show auto-load safe-path
389 Set a list of directories from which it is safe to auto-load files.
390 The delimiter (':' above) may differ according to the host platform.
392 set debug auto-load on|off
394 Control display of debugging info for auto-loading the files above.
396 set dprintf-style gdb|call|agent
398 Control the way in which a dynamic printf is performed; "gdb"
399 requests a GDB printf command, while "call" causes dprintf to call a
400 function in the inferior. "agent" requests that the target agent
401 (such as GDBserver) do the printing.
403 set dprintf-function <expr>
404 show dprintf-function
405 set dprintf-channel <expr>
407 Set the function and optional first argument to the call when using
408 the "call" style of dynamic printf.
410 set disconnected-dprintf on|off
411 show disconnected-dprintf
412 Control whether agent-style dynamic printfs continue to be in effect
413 after GDB disconnects.
415 * New configure options
418 Configure default value for the 'set auto-load scripts-directory'
419 setting above. It defaults to '$debugdir:$datadir/auto-load',
420 $debugdir representing global debugging info directories (available
421 via 'show debug-file-directory') and $datadir representing GDB's data
422 directory (available via 'show data-directory').
424 --with-auto-load-safe-path
425 Configure default value for the 'set auto-load safe-path' setting
426 above. It defaults to the --with-auto-load-dir setting.
428 --without-auto-load-safe-path
429 Set 'set auto-load safe-path' to '/', effectively disabling this
434 z0/z1 conditional breakpoints extension
436 The z0/z1 breakpoint insertion packets have been extended to carry
437 a list of conditional expressions over to the remote stub depending on the
438 condition evaluation mode. The use of this extension can be controlled
439 via the "set remote conditional-breakpoints-packet" command.
443 Specify the signals which the remote stub may pass to the debugged
444 program without GDB involvement.
446 * New command line options
448 --init-command=FILE, -ix Like --command, -x but execute it
449 before loading inferior.
450 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
451 execute it before loading inferior.
453 *** Changes in GDB 7.4
455 * GDB now handles ambiguous linespecs more consistently; the existing
456 FILE:LINE support has been expanded to other types of linespecs. A
457 breakpoint will now be set on all matching locations in all
458 inferiors, and locations will be added or removed according to
461 * GDB now allows you to skip uninteresting functions and files when
462 stepping with the "skip function" and "skip file" commands.
464 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
465 and "show remote hardware-watchpoint-length-limit". These allows to
466 set or show the maximum length limit (in bytes) of a remote
467 target hardware watchpoint.
469 This allows e.g. to use "unlimited" hardware watchpoints with the
470 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
471 watchpoints are slower than real hardware watchpoints but are
472 significantly faster than gdb software watchpoints.
476 ** The register_pretty_printer function in module gdb.printing now takes
477 an optional `replace' argument. If True, the new printer replaces any
480 ** The "maint set python print-stack on|off" command has been
481 deprecated and will be deleted in GDB 7.5.
482 A new command: "set python print-stack none|full|message" has
483 replaced it. Additionally, the default for "print-stack" is
484 now "message", which just prints the error message without
487 ** A prompt substitution hook (prompt_hook) is now available to the
490 ** A new Python module, gdb.prompt has been added to the GDB Python
491 modules library. This module provides functionality for
492 escape sequences in prompts (used by set/show
493 extended-prompt). These escape sequences are replaced by their
496 ** Python commands and convenience-functions located in
497 'data-directory'/python/gdb/command and
498 'data-directory'/python/gdb/function are now automatically loaded
501 ** Blocks now provide four new attributes. global_block and
502 static_block will return the global and static blocks
503 respectively. is_static and is_global are boolean attributes
504 that indicate if the block is one of those two types.
506 ** Symbols now provide the "type" attribute, the type of the symbol.
508 ** The "gdb.breakpoint" function has been deprecated in favor of
511 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
512 of a function. This class is based on the "finish" command
513 available in the CLI.
515 ** Type objects for struct and union types now allow access to
516 the fields using standard Python dictionary (mapping) methods.
517 For example, "some_type['myfield']" now works, as does
520 ** A new event "gdb.new_objfile" has been added, triggered by loading a
523 ** A new function, "deep_items" has been added to the gdb.types
524 module in the GDB Python modules library. This function returns
525 an iterator over the fields of a struct or union type. Unlike
526 the standard Python "iteritems" method, it will recursively traverse
527 any anonymous fields.
531 ** "*stopped" events can report several new "reason"s, such as
534 ** Breakpoint changes are now notified using new async records, like
535 "=breakpoint-modified".
537 ** New command -ada-task-info.
539 * libthread-db-search-path now supports two special values: $sdir and $pdir.
540 $sdir specifies the default system locations of shared libraries.
541 $pdir specifies the directory where the libpthread used by the application
544 GDB no longer looks in $sdir and $pdir after it has searched the directories
545 mentioned in libthread-db-search-path. If you want to search those
546 directories, they must be specified in libthread-db-search-path.
547 The default value of libthread-db-search-path on GNU/Linux and Solaris
548 systems is now "$sdir:$pdir".
550 $pdir is not supported by gdbserver, it is currently ignored.
551 $sdir is supported by gdbserver.
553 * New configure option --with-iconv-bin.
554 When using the internationalization support like the one in the GNU C
555 library, GDB will invoke the "iconv" program to get a list of supported
556 character sets. If this program lives in a non-standard location, one can
557 use this option to specify where to find it.
559 * When natively debugging programs on PowerPC BookE processors running
560 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
561 watchpoints, which specify a mask in addition to an address to watch.
562 The mask specifies that some bits of an address (the bits which are
563 reset in the mask) should be ignored when matching the address accessed
564 by the inferior against the watchpoint address. See the "PowerPC Embedded"
565 section in the user manual for more details.
567 * The new option --once causes GDBserver to stop listening for connections once
568 the first connection is made. The listening port used by GDBserver will
569 become available after that.
571 * New commands "info macros" and "alias" have been added.
573 * New function parameters suffix @entry specifies value of function parameter
574 at the time the function got called. Entry values are available only since
580 "!" is now an alias of the "shell" command.
581 Note that no space is needed between "!" and SHELL COMMAND.
585 watch EXPRESSION mask MASK_VALUE
586 The watch command now supports the mask argument which allows creation
587 of masked watchpoints, if the current architecture supports this feature.
589 info auto-load-scripts [REGEXP]
590 This command was formerly named "maintenance print section-scripts".
591 It is now generally useful and is no longer a maintenance-only command.
593 info macro [-all] [--] MACRO
594 The info macro command has new options `-all' and `--'. The first for
595 printing all definitions of a macro. The second for explicitly specifying
596 the end of arguments and the beginning of the macro name in case the macro
597 name starts with a hyphen.
599 collect[/s] EXPRESSIONS
600 The tracepoint collect command now takes an optional modifier "/s"
601 that directs it to dereference pointer-to-character types and
602 collect the bytes of memory up to a zero byte. The behavior is
603 similar to what you see when you use the regular print command on a
604 string. An optional integer following the "/s" sets a bound on the
605 number of bytes that will be collected.
608 The trace start command now interprets any supplied arguments as a
609 note to be recorded with the trace run, with an effect similar to
610 setting the variable trace-notes.
613 The trace stop command now interprets any arguments as a note to be
614 mentioned along with the tstatus report that the trace was stopped
615 with a command. The effect is similar to setting the variable
618 * Tracepoints can now be enabled and disabled at any time after a trace
619 experiment has been started using the standard "enable" and "disable"
620 commands. It is now possible to start a trace experiment with no enabled
621 tracepoints; GDB will display a warning, but will allow the experiment to
622 begin, assuming that tracepoints will be enabled as needed while the trace
625 * Fast tracepoints on 32-bit x86-architectures can now be placed at
626 locations with 4-byte instructions, when they were previously
627 limited to locations with instructions of 5 bytes or longer.
631 set debug dwarf2-read
632 show debug dwarf2-read
633 Turns on or off display of debugging messages related to reading
634 DWARF debug info. The default is off.
636 set debug symtab-create
637 show debug symtab-create
638 Turns on or off display of debugging messages related to symbol table
639 creation. The default is off.
643 Set the GDB prompt, and allow escape sequences to be inserted to
644 display miscellaneous information (see 'help set extended-prompt'
645 for the list of sequences). This prompt (and any information
646 accessed through the escape sequences) is updated every time the
649 set print entry-values (both|compact|default|if-needed|no|only|preferred)
650 show print entry-values
651 Set printing of frame argument values at function entry. In some cases
652 GDB can determine the value of function argument which was passed by the
653 function caller, even if the value was modified inside the called function.
655 set debug entry-values
656 show debug entry-values
657 Control display of debugging info for determining frame argument values at
658 function entry and virtual tail call frames.
660 set basenames-may-differ
661 show basenames-may-differ
662 Set whether a source file may have multiple base names.
663 (A "base name" is the name of a file with the directory part removed.
664 Example: The base name of "/home/user/hello.c" is "hello.c".)
665 If set, GDB will canonicalize file names (e.g., expand symlinks)
666 before comparing them. Canonicalization is an expensive operation,
667 but it allows the same file be known by more than one base name.
668 If not set (the default), all source files are assumed to have just
669 one base name, and gdb will do file name comparisons more efficiently.
675 Set a user name and notes for the current and any future trace runs.
676 This is useful for long-running and/or disconnected traces, to
677 inform others (or yourself) as to who is running the trace, supply
678 contact information, or otherwise explain what is going on.
681 show trace-stop-notes
682 Set a note attached to the trace run, that is displayed when the
683 trace has been stopped by a tstop command. This is useful for
684 instance as an explanation, if you are stopping a trace run that was
685 started by someone else.
691 Dynamically enable a tracepoint in a started trace experiment.
695 Dynamically disable a tracepoint in a started trace experiment.
699 Set the user and notes of the trace run.
703 Query the current status of a tracepoint.
707 Query the minimum length of instruction at which a fast tracepoint may
710 * Dcache size (number of lines) and line-size are now runtime-configurable
711 via "set dcache line" and "set dcache line-size" commands.
715 Texas Instruments TMS320C6x tic6x-*-*
719 Renesas RL78 rl78-*-elf
721 *** Changes in GDB 7.3.1
723 * The build failure for NetBSD and OpenBSD targets have now been fixed.
725 *** Changes in GDB 7.3
727 * GDB has a new command: "thread find [REGEXP]".
728 It finds the thread id whose name, target id, or thread extra info
729 matches the given regular expression.
731 * The "catch syscall" command now works on mips*-linux* targets.
733 * The -data-disassemble MI command now supports modes 2 and 3 for
734 dumping the instruction opcodes.
736 * New command line options
738 -data-directory DIR Specify DIR as the "data-directory".
739 This is mostly for testing purposes.
741 * The "maint set python auto-load on|off" command has been renamed to
742 "set auto-load-scripts on|off".
744 * GDB has a new command: "set directories".
745 It is like the "dir" command except that it replaces the
746 source path list instead of augmenting it.
748 * GDB now understands thread names.
750 On GNU/Linux, "info threads" will display the thread name as set by
751 prctl or pthread_setname_np.
753 There is also a new command, "thread name", which can be used to
754 assign a name internally for GDB to display.
757 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
758 has been integrated into GDB.
762 ** The function gdb.Write now accepts an optional keyword 'stream'.
763 This keyword, when provided, will direct the output to either
764 stdout, stderr, or GDB's logging output.
766 ** Parameters can now be be sub-classed in Python, and in particular
767 you may implement the get_set_doc and get_show_doc functions.
768 This improves how Parameter set/show documentation is processed
769 and allows for more dynamic content.
771 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
772 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
773 have an is_valid method.
775 ** Breakpoints can now be sub-classed in Python, and in particular
776 you may implement a 'stop' function that is executed each time
777 the inferior reaches that breakpoint.
779 ** New function gdb.lookup_global_symbol looks up a global symbol.
781 ** GDB values in Python are now callable if the value represents a
782 function. For example, if 'some_value' represents a function that
783 takes two integer parameters and returns a value, you can call
784 that function like so:
786 result = some_value (10,20)
788 ** Module gdb.types has been added.
789 It contains a collection of utilities for working with gdb.Types objects:
790 get_basic_type, has_field, make_enum_dict.
792 ** Module gdb.printing has been added.
793 It contains utilities for writing and registering pretty-printers.
794 New classes: PrettyPrinter, SubPrettyPrinter,
795 RegexpCollectionPrettyPrinter.
796 New function: register_pretty_printer.
798 ** New commands "info pretty-printers", "enable pretty-printer" and
799 "disable pretty-printer" have been added.
801 ** gdb.parameter("directories") is now available.
803 ** New function gdb.newest_frame returns the newest frame in the
806 ** The gdb.InferiorThread class has a new "name" attribute. This
807 holds the thread's name.
809 ** Python Support for Inferior events.
810 Python scripts can add observers to be notified of events
811 occurring in the process being debugged.
812 The following events are currently supported:
813 - gdb.events.cont Continue event.
814 - gdb.events.exited Inferior exited event.
815 - gdb.events.stop Signal received, and Breakpoint hit events.
819 ** GDB now puts template parameters in scope when debugging in an
820 instantiation. For example, if you have:
822 template<int X> int func (void) { return X; }
824 then if you step into func<5>, "print X" will show "5". This
825 feature requires proper debuginfo support from the compiler; it
826 was added to GCC 4.5.
828 ** The motion commands "next", "finish", "until", and "advance" now
829 work better when exceptions are thrown. In particular, GDB will
830 no longer lose control of the inferior; instead, the GDB will
831 stop the inferior at the point at which the exception is caught.
832 This functionality requires a change in the exception handling
833 code that was introduced in GCC 4.5.
835 * GDB now follows GCC's rules on accessing volatile objects when
836 reading or writing target state during expression evaluation.
837 One notable difference to prior behavior is that "print x = 0"
838 no longer generates a read of x; the value of the assignment is
839 now always taken directly from the value being assigned.
841 * GDB now has some support for using labels in the program's source in
842 linespecs. For instance, you can use "advance label" to continue
843 execution to a label.
845 * GDB now has support for reading and writing a new .gdb_index
846 section. This section holds a fast index of DWARF debugging
847 information and can be used to greatly speed up GDB startup and
848 operation. See the documentation for `save gdb-index' for details.
850 * The "watch" command now accepts an optional "-location" argument.
851 When used, this causes GDB to watch the memory referred to by the
852 expression. Such a watchpoint is never deleted due to it going out
855 * GDB now supports thread debugging of core dumps on GNU/Linux.
857 GDB now activates thread debugging using the libthread_db library
858 when debugging GNU/Linux core dumps, similarly to when debugging
859 live processes. As a result, when debugging a core dump file, GDB
860 is now able to display pthread_t ids of threads. For example, "info
861 threads" shows the same output as when debugging the process when it
862 was live. In earlier releases, you'd see something like this:
865 * 1 LWP 6780 main () at main.c:10
867 While now you see this:
870 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
872 It is also now possible to inspect TLS variables when debugging core
875 When debugging a core dump generated on a machine other than the one
876 used to run GDB, you may need to point GDB at the correct
877 libthread_db library with the "set libthread-db-search-path"
878 command. See the user manual for more details on this command.
880 * When natively debugging programs on PowerPC BookE processors running
881 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
882 which stop execution of the inferior whenever it executes an instruction
883 at any address within the specified range. See the "PowerPC Embedded"
884 section in the user manual for more details.
886 * New features in the GDB remote stub, GDBserver
888 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
889 and i686 LynxOS (version 5.x).
891 ** GDBserver is now supported on Blackfin Linux.
893 * New native configurations
895 ia64 HP-UX ia64-*-hpux*
899 Analog Devices, Inc. Blackfin Processor bfin-*
901 * Ada task switching is now supported on sparc-elf targets when
902 debugging a program using the Ravenscar Profile. For more information,
903 see the "Tasking Support when using the Ravenscar Profile" section
904 in the GDB user manual.
906 * Guile support was removed.
908 * New features in the GNU simulator
910 ** The --map-info flag lists all known core mappings.
912 ** CFI flashes may be simulated via the "cfi" device.
914 *** Changes in GDB 7.2
916 * Shared library support for remote targets by default
918 When GDB is configured for a generic, non-OS specific target, like
919 for example, --target=arm-eabi or one of the many *-*-elf targets,
920 GDB now queries remote stubs for loaded shared libraries using the
921 `qXfer:libraries:read' packet. Previously, shared library support
922 was always disabled for such configurations.
926 ** Argument Dependent Lookup (ADL)
928 In C++ ADL lookup directs function search to the namespaces of its
929 arguments even if the namespace has not been imported.
939 Here the compiler will search for `foo' in the namespace of 'b'
940 and find A::foo. GDB now supports this. This construct is commonly
941 used in the Standard Template Library for operators.
943 ** Improved User Defined Operator Support
945 In addition to member operators, GDB now supports lookup of operators
946 defined in a namespace and imported with a `using' directive, operators
947 defined in the global scope, operators imported implicitly from an
948 anonymous namespace, and the ADL operators mentioned in the previous
950 GDB now also supports proper overload resolution for all the previously
951 mentioned flavors of operators.
953 ** static const class members
955 Printing of static const class members that are initialized in the
956 class definition has been fixed.
958 * Windows Thread Information Block access.
960 On Windows targets, GDB now supports displaying the Windows Thread
961 Information Block (TIB) structure. This structure is visible either
962 by using the new command `info w32 thread-information-block' or, by
963 dereferencing the new convenience variable named `$_tlb', a
964 thread-specific pointer to the TIB. This feature is also supported
965 when remote debugging using GDBserver.
969 Static tracepoints are calls in the user program into a tracing
970 library. One such library is a port of the LTTng kernel tracer to
971 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
972 When debugging with GDBserver, GDB now supports combining the GDB
973 tracepoint machinery with such libraries. For example: the user can
974 use GDB to probe a static tracepoint marker (a call from the user
975 program into the tracing library) with the new "strace" command (see
976 "New commands" below). This creates a "static tracepoint" in the
977 breakpoint list, that can be manipulated with the same feature set
978 as fast and regular tracepoints. E.g., collect registers, local and
979 global variables, collect trace state variables, and define
980 tracepoint conditions. In addition, the user can collect extra
981 static tracepoint marker specific data, by collecting the new
982 $_sdata internal variable. When analyzing the trace buffer, you can
983 inspect $_sdata like any other variable available to GDB. For more
984 information, see the "Tracepoints" chapter in GDB user manual. New
985 remote packets have been defined to support static tracepoints, see
986 the "New remote packets" section below.
988 * Better reconstruction of tracepoints after disconnected tracing
990 GDB will attempt to download the original source form of tracepoint
991 definitions when starting a trace run, and then will upload these
992 upon reconnection to the target, resulting in a more accurate
993 reconstruction of the tracepoints that are in use on the target.
997 You can now exercise direct control over the ways that GDB can
998 affect your program. For instance, you can disallow the setting of
999 breakpoints, so that the program can run continuously (assuming
1000 non-stop mode). In addition, the "observer" variable is available
1001 to switch all of the different controls; in observer mode, GDB
1002 cannot affect the target's behavior at all, which is useful for
1003 tasks like diagnosing live systems in the field.
1005 * The new convenience variable $_thread holds the number of the
1008 * New remote packets
1012 Return the address of the Windows Thread Information Block of a given thread.
1016 In response to several of the tracepoint packets, the target may now
1017 also respond with a number of intermediate `qRelocInsn' request
1018 packets before the final result packet, to have GDB handle
1019 relocating an instruction to execute at a different address. This
1020 is particularly useful for stubs that support fast tracepoints. GDB
1021 reports support for this feature in the qSupported packet.
1025 List static tracepoint markers in the target program.
1029 List static tracepoint markers at a given address in the target
1032 qXfer:statictrace:read
1034 Read the static trace data collected (by a `collect $_sdata'
1035 tracepoint action). The remote stub reports support for this packet
1036 to gdb's qSupported query.
1040 Send the current settings of GDB's permission flags.
1044 Send part of the source (textual) form of a tracepoint definition,
1045 which includes location, conditional, and action list.
1047 * The source command now accepts a -s option to force searching for the
1048 script in the source search path even if the script name specifies
1051 * New features in the GDB remote stub, GDBserver
1053 - GDBserver now support tracepoints (including fast tracepoints, and
1054 static tracepoints). The feature is currently supported by the
1055 i386-linux and amd64-linux builds. See the "Tracepoints support
1056 in gdbserver" section in the manual for more information.
1058 GDBserver JIT compiles the tracepoint's conditional agent
1059 expression bytecode into native code whenever possible for low
1060 overhead dynamic tracepoints conditionals. For such tracepoints,
1061 an expression that examines program state is evaluated when the
1062 tracepoint is reached, in order to determine whether to capture
1063 trace data. If the condition is simple and false, processing the
1064 tracepoint finishes very quickly and no data is gathered.
1066 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1067 for static tracepoints support.
1069 - GDBserver now supports x86_64 Windows 64-bit debugging.
1071 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1072 it understands register description.
1074 * The --batch flag now disables pagination and queries.
1076 * X86 general purpose registers
1078 GDB now supports reading/writing byte, word and double-word x86
1079 general purpose registers directly. This means you can use, say,
1080 $ah or $ax to refer, respectively, to the byte register AH and
1081 16-bit word register AX that are actually portions of the 32-bit
1082 register EAX or 64-bit register RAX.
1084 * The `commands' command now accepts a range of breakpoints to modify.
1085 A plain `commands' following a command that creates multiple
1086 breakpoints affects all the breakpoints set by that command. This
1087 applies to breakpoints set by `rbreak', and also applies when a
1088 single `break' command creates multiple breakpoints (e.g.,
1089 breakpoints on overloaded c++ functions).
1091 * The `rbreak' command now accepts a filename specification as part of
1092 its argument, limiting the functions selected by the regex to those
1093 in the specified file.
1095 * Support for remote debugging Windows and SymbianOS shared libraries
1096 from Unix hosts has been improved. Non Windows GDB builds now can
1097 understand target reported file names that follow MS-DOS based file
1098 system semantics, such as file names that include drive letters and
1099 use the backslash character as directory separator. This makes it
1100 possible to transparently use the "set sysroot" and "set
1101 solib-search-path" on Unix hosts to point as host copies of the
1102 target's shared libraries. See the new command "set
1103 target-file-system-kind" described below, and the "Commands to
1104 specify files" section in the user manual for more information.
1108 eval template, expressions...
1109 Convert the values of one or more expressions under the control
1110 of the string template to a command line, and call it.
1112 set target-file-system-kind unix|dos-based|auto
1113 show target-file-system-kind
1114 Set or show the assumed file system kind for target reported file
1117 save breakpoints <filename>
1118 Save all current breakpoint definitions to a file suitable for use
1119 in a later debugging session. To read the saved breakpoint
1120 definitions, use the `source' command.
1122 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1125 info static-tracepoint-markers
1126 Display information about static tracepoint markers in the target.
1128 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1129 Define a static tracepoint by probing a marker at the given
1130 function, line, address, or marker ID.
1134 Enable and disable observer mode.
1136 set may-write-registers on|off
1137 set may-write-memory on|off
1138 set may-insert-breakpoints on|off
1139 set may-insert-tracepoints on|off
1140 set may-insert-fast-tracepoints on|off
1141 set may-interrupt on|off
1142 Set individual permissions for GDB effects on the target. Note that
1143 some of these settings can have undesirable or surprising
1144 consequences, particularly when changed in the middle of a session.
1145 For instance, disabling the writing of memory can prevent
1146 breakpoints from being inserted, cause single-stepping to fail, or
1147 even crash your program, if you disable after breakpoints have been
1148 inserted. However, GDB should not crash.
1150 set record memory-query on|off
1151 show record memory-query
1152 Control whether to stop the inferior if memory changes caused
1153 by an instruction cannot be recorded.
1158 The disassemble command now supports "start,+length" form of two arguments.
1162 ** GDB now provides a new directory location, called the python directory,
1163 where Python scripts written for GDB can be installed. The location
1164 of that directory is <data-directory>/python, where <data-directory>
1165 is the GDB data directory. For more details, see section `Scripting
1166 GDB using Python' in the manual.
1168 ** The GDB Python API now has access to breakpoints, symbols, symbol
1169 tables, program spaces, inferiors, threads and frame's code blocks.
1170 Additionally, GDB Parameters can now be created from the API, and
1171 manipulated via set/show in the CLI.
1173 ** New functions gdb.target_charset, gdb.target_wide_charset,
1174 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1176 ** New exception gdb.GdbError.
1178 ** Pretty-printers are now also looked up in the current program space.
1180 ** Pretty-printers can now be individually enabled and disabled.
1182 ** GDB now looks for names of Python scripts to auto-load in a
1183 special section named `.debug_gdb_scripts', in addition to looking
1184 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1186 * Tracepoint actions were unified with breakpoint commands. In particular,
1187 there are no longer differences in "info break" output for breakpoints and
1188 tracepoints and the "commands" command can be used for both tracepoints and
1189 regular breakpoints.
1193 ARM Symbian arm*-*-symbianelf*
1195 * D language support.
1196 GDB now supports debugging programs written in the D programming
1199 * GDB now supports the extended ptrace interface for PowerPC which is
1200 available since Linux kernel version 2.6.34. This automatically enables
1201 any hardware breakpoints and additional hardware watchpoints available in
1202 the processor. The old ptrace interface exposes just one hardware
1203 watchpoint and no hardware breakpoints.
1205 * GDB is now able to use the Data Value Compare (DVC) register available on
1206 embedded PowerPC processors to implement in hardware simple watchpoint
1207 conditions of the form:
1209 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1211 This works in native GDB running on Linux kernels with the extended ptrace
1212 interface mentioned above.
1214 *** Changes in GDB 7.1
1218 ** Namespace Support
1220 GDB now supports importing of namespaces in C++. This enables the
1221 user to inspect variables from imported namespaces. Support for
1222 namepace aliasing has also been added. So, if a namespace is
1223 aliased in the current scope (e.g. namepace C=A; ) the user can
1224 print variables using the alias (e.g. (gdb) print C::x).
1228 All known bugs relating to the printing of virtual base class were
1229 fixed. It is now possible to call overloaded static methods using a
1234 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1235 and reinterpret_cast<> are now handled by the C++ expression parser.
1239 Xilinx MicroBlaze microblaze-*-*
1244 Xilinx MicroBlaze microblaze
1247 * Multi-program debugging.
1249 GDB now has support for multi-program (a.k.a. multi-executable or
1250 multi-exec) debugging. This allows for debugging multiple inferiors
1251 simultaneously each running a different program under the same GDB
1252 session. See "Debugging Multiple Inferiors and Programs" in the
1253 manual for more information. This implied some user visible changes
1254 in the multi-inferior support. For example, "info inferiors" now
1255 lists inferiors that are not running yet or that have exited
1256 already. See also "New commands" and "New options" below.
1258 * New tracing features
1260 GDB's tracepoint facility now includes several new features:
1262 ** Trace state variables
1264 GDB tracepoints now include support for trace state variables, which
1265 are variables managed by the target agent during a tracing
1266 experiment. They are useful for tracepoints that trigger each
1267 other, so for instance one tracepoint can count hits in a variable,
1268 and then a second tracepoint has a condition that is true when the
1269 count reaches a particular value. Trace state variables share the
1270 $-syntax of GDB convenience variables, and can appear in both
1271 tracepoint actions and condition expressions. Use the "tvariable"
1272 command to create, and "info tvariables" to view; see "Trace State
1273 Variables" in the manual for more detail.
1277 GDB now includes an option for defining fast tracepoints, which
1278 targets may implement more efficiently, such as by installing a jump
1279 into the target agent rather than a trap instruction. The resulting
1280 speedup can be by two orders of magnitude or more, although the
1281 tradeoff is that some program locations on some target architectures
1282 might not allow fast tracepoint installation, for instance if the
1283 instruction to be replaced is shorter than the jump. To request a
1284 fast tracepoint, use the "ftrace" command, with syntax identical to
1285 the regular trace command.
1287 ** Disconnected tracing
1289 It is now possible to detach GDB from the target while it is running
1290 a trace experiment, then reconnect later to see how the experiment
1291 is going. In addition, a new variable disconnected-tracing lets you
1292 tell the target agent whether to continue running a trace if the
1293 connection is lost unexpectedly.
1297 GDB now has the ability to save the trace buffer into a file, and
1298 then use that file as a target, similarly to you can do with
1299 corefiles. You can select trace frames, print data that was
1300 collected in them, and use tstatus to display the state of the
1301 tracing run at the moment that it was saved. To create a trace
1302 file, use "tsave <filename>", and to use it, do "target tfile
1305 ** Circular trace buffer
1307 You can ask the target agent to handle the trace buffer as a
1308 circular buffer, discarding the oldest trace frames to make room for
1309 newer ones, by setting circular-trace-buffer to on. This feature may
1310 not be available for all target agents.
1315 The disassemble command, when invoked with two arguments, now requires
1316 the arguments to be comma-separated.
1319 The info variables command now displays variable definitions. Files
1320 which only declare a variable are not shown.
1323 The source command is now capable of sourcing Python scripts.
1324 This feature is dependent on the debugger being build with Python
1327 Related to this enhancement is also the introduction of a new command
1328 "set script-extension" (see below).
1330 * New commands (for set/show, see "New options" below)
1332 record save [<FILENAME>]
1333 Save a file (in core file format) containing the process record
1334 execution log for replay debugging at a later time.
1336 record restore <FILENAME>
1337 Restore the process record execution log that was saved at an
1338 earlier time, for replay debugging.
1340 add-inferior [-copies <N>] [-exec <FILENAME>]
1343 clone-inferior [-copies <N>] [ID]
1344 Make a new inferior ready to execute the same program another
1345 inferior has loaded.
1350 maint info program-spaces
1351 List the program spaces loaded into GDB.
1353 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1354 show remote interrupt-sequence
1355 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1356 as the sequence to the remote target in order to interrupt the execution.
1357 Ctrl-C is a default. Some system prefers BREAK which is high level of
1358 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1359 Magic SysRq g. It is BREAK signal and character 'g'.
1361 set remote interrupt-on-connect [on | off]
1362 show remote interrupt-on-connect
1363 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1364 remote target when gdb connects to it. This is needed when you debug
1367 set remotebreak [on | off]
1369 Deprecated. Use "set/show remote interrupt-sequence" instead.
1371 tvariable $NAME [ = EXP ]
1372 Create or modify a trace state variable.
1375 List trace state variables and their values.
1377 delete tvariable $NAME ...
1378 Delete one or more trace state variables.
1381 Evaluate the given expressions without collecting anything into the
1382 trace buffer. (Valid in tracepoint actions only.)
1384 ftrace FN / FILE:LINE / *ADDR
1385 Define a fast tracepoint at the given function, line, or address.
1387 * New expression syntax
1389 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1390 GDB now parses 0b101010 identically with 42.
1394 set follow-exec-mode new|same
1395 show follow-exec-mode
1396 Control whether GDB reuses the same inferior across an exec call or
1397 creates a new one. This is useful to be able to restart the old
1398 executable after the inferior having done an exec call.
1400 set default-collect EXPR, ...
1401 show default-collect
1402 Define a list of expressions to be collected at each tracepoint.
1403 This is a useful way to ensure essential items are not overlooked,
1404 such as registers or a critical global variable.
1406 set disconnected-tracing
1407 show disconnected-tracing
1408 If set to 1, the target is instructed to continue tracing if it
1409 loses its connection to GDB. If 0, the target is to stop tracing
1412 set circular-trace-buffer
1413 show circular-trace-buffer
1414 If set to on, the target is instructed to use a circular trace buffer
1415 and discard the oldest trace frames instead of stopping the trace due
1416 to a full trace buffer. If set to off, the trace stops when the buffer
1417 fills up. Some targets may not support this.
1419 set script-extension off|soft|strict
1420 show script-extension
1421 If set to "off", the debugger does not perform any script language
1422 recognition, and all sourced files are assumed to be GDB scripts.
1423 If set to "soft" (the default), files are sourced according to
1424 filename extension, falling back to GDB scripts if the first
1426 If set to "strict", files are sourced according to filename extension.
1428 set ada trust-PAD-over-XVS on|off
1429 show ada trust-PAD-over-XVS
1430 If off, activate a workaround against a bug in the debugging information
1431 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1432 the GCC sources for more information about the GNAT encoding and
1433 PAD types in particular). It is always safe to set this option to
1434 off, but this introduces a slight performance penalty. The default
1437 * Python API Improvements
1439 ** GDB provides the new class gdb.LazyString. This is useful in
1440 some pretty-printing cases. The new method gdb.Value.lazy_string
1441 provides a simple way to create objects of this type.
1443 ** The fields returned by gdb.Type.fields now have an
1444 `is_base_class' attribute.
1446 ** The new method gdb.Type.range returns the range of an array type.
1448 ** The new method gdb.parse_and_eval can be used to parse and
1449 evaluate an expression.
1451 * New remote packets
1454 Define a trace state variable.
1457 Get the current value of a trace state variable.
1460 Set desired tracing behavior upon disconnection.
1463 Set the trace buffer to be linear or circular.
1466 Get data about the tracepoints currently in use.
1470 Process record now works correctly with hardware watchpoints.
1472 Multiple bug fixes have been made to the mips-irix port, making it
1473 much more reliable. In particular:
1474 - Debugging threaded applications is now possible again. Previously,
1475 GDB would hang while starting the program, or while waiting for
1476 the program to stop at a breakpoint.
1477 - Attaching to a running process no longer hangs.
1478 - An error occurring while loading a core file has been fixed.
1479 - Changing the value of the PC register now works again. This fixes
1480 problems observed when using the "jump" command, or when calling
1481 a function from GDB, or even when assigning a new value to $pc.
1482 - With the "finish" and "return" commands, the return value for functions
1483 returning a small array is now correctly printed.
1484 - It is now possible to break on shared library code which gets executed
1485 during a shared library init phase (code executed while executing
1486 their .init section). Previously, the breakpoint would have no effect.
1487 - GDB is now able to backtrace through the signal handler for
1488 non-threaded programs.
1490 PIE (Position Independent Executable) programs debugging is now supported.
1491 This includes debugging execution of PIC (Position Independent Code) shared
1492 libraries although for that, it should be possible to run such libraries as an
1495 *** Changes in GDB 7.0
1497 * GDB now has an interface for JIT compilation. Applications that
1498 dynamically generate code can create symbol files in memory and register
1499 them with GDB. For users, the feature should work transparently, and
1500 for JIT developers, the interface is documented in the GDB manual in the
1501 "JIT Compilation Interface" chapter.
1503 * Tracepoints may now be conditional. The syntax is as for
1504 breakpoints; either an "if" clause appended to the "trace" command,
1505 or the "condition" command is available. GDB sends the condition to
1506 the target for evaluation using the same bytecode format as is used
1507 for tracepoint actions.
1509 * The disassemble command now supports: an optional /r modifier, print the
1510 raw instructions in hex as well as in symbolic form, and an optional /m
1511 modifier to print mixed source+assembly.
1513 * Process record and replay
1515 In a architecture environment that supports ``process record and
1516 replay'', ``process record and replay'' target can record a log of
1517 the process execution, and replay it with both forward and reverse
1520 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1521 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1522 set execution-direction {forward|reverse}, for targets that support
1525 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1526 feature is available with a native GDB running on kernel version
1529 * GDB now has support for multi-byte and wide character sets on the
1530 target. Strings whose character type is wchar_t, char16_t, or
1531 char32_t are now correctly printed. GDB supports wide- and unicode-
1532 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1533 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1534 `printf'. This feature requires iconv to work properly; if your
1535 system does not have a working iconv, GDB can use GNU libiconv. See
1536 the installation instructions for more information.
1538 * GDB now supports automatic retrieval of shared library files from
1539 remote targets. To use this feature, specify a system root that begins
1540 with the `remote:' prefix, either via the `set sysroot' command or via
1541 the `--with-sysroot' configure-time option.
1543 * "info sharedlibrary" now takes an optional regex of libraries to show,
1544 and it now reports if a shared library has no debugging information.
1546 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1547 now complete on file names.
1549 * When completing in expressions, gdb will attempt to limit
1550 completions to allowable structure or union fields, where appropriate.
1551 For instance, consider:
1553 # struct example { int f1; double f2; };
1554 # struct example variable;
1557 If the user types TAB at the end of this command line, the available
1558 completions will be "f1" and "f2".
1560 * Inlined functions are now supported. They show up in backtraces, and
1561 the "step", "next", and "finish" commands handle them automatically.
1563 * GDB now supports the token-splicing (##) and stringification (#)
1564 operators when expanding macros. It also supports variable-arity
1567 * GDB now supports inspecting extra signal information, exported by
1568 the new $_siginfo convenience variable. The feature is currently
1569 implemented on linux ARM, i386 and amd64.
1571 * GDB can now display the VFP floating point registers and NEON vector
1572 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1573 can provide these registers (requires Linux 2.6.30 or later). Remote
1574 and simulator targets may also provide them.
1576 * New remote packets
1579 Search memory for a sequence of bytes.
1582 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1583 operation over reliable transport links. Use of this packet is
1584 controlled by the `set remote noack-packet' command.
1587 Kill the process with the specified process ID. Use this in preference
1588 to `k' when multiprocess protocol extensions are supported.
1591 Obtains additional operating system information
1595 Read or write additional signal information.
1597 * Removed remote protocol undocumented extension
1599 An undocumented extension to the remote protocol's `S' stop reply
1600 packet that permited the stub to pass a process id was removed.
1601 Remote servers should use the `T' stop reply packet instead.
1603 * GDB now supports multiple function calling conventions according to the
1604 DWARF-2 DW_AT_calling_convention function attribute.
1606 * The SH target utilizes the aforementioned change to distinguish between gcc
1607 and Renesas calling convention. It also adds the new CLI commands
1608 `set/show sh calling-convention'.
1610 * GDB can now read compressed debug sections, as produced by GNU gold
1611 with the --compress-debug-sections=zlib flag.
1613 * 64-bit core files are now supported on AIX.
1615 * Thread switching is now supported on Tru64.
1617 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1618 which will be allocated using malloc later in program execution.
1620 * The qXfer:libraries:read remote procotol packet now allows passing a
1621 list of section offsets.
1623 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1624 conditions handling signals delivered during attach or thread creation
1625 have also been fixed.
1627 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1628 From the user's standpoint, all unqualified instances of True and False
1629 are treated as the standard definitions, regardless of context.
1631 * GDB now parses C++ symbol and type names more flexibly. For
1634 template<typename T> class C { };
1637 GDB will now correctly handle all of:
1639 ptype C<char const *>
1640 ptype C<char const*>
1641 ptype C<const char *>
1642 ptype C<const char*>
1644 * New features in the GDB remote stub, gdbserver
1646 - The "--wrapper" command-line argument tells gdbserver to use a
1647 wrapper program to launch programs for debugging.
1649 - On PowerPC and S/390 targets, it is now possible to use a single
1650 gdbserver executable to debug both 32-bit and 64-bit programs.
1651 (This requires gdbserver itself to be built as a 64-bit executable.)
1653 - gdbserver uses the new noack protocol mode for TCP connections to
1654 reduce communications latency, if also supported and enabled in GDB.
1656 - Support for the sparc64-linux-gnu target is now included in
1659 - The amd64-linux build of gdbserver now supports debugging both
1660 32-bit and 64-bit programs.
1662 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1663 now support hardware watchpoints, and will use them automatically
1668 GDB now has support for scripting using Python. Whether this is
1669 available is determined at configure time.
1671 New GDB commands can now be written in Python.
1673 * Ada tasking support
1675 Ada tasks can now be inspected in GDB. The following commands have
1679 Print the list of Ada tasks.
1681 Print detailed information about task number N.
1683 Print the task number of the current task.
1685 Switch the context of debugging to task number N.
1687 * Support for user-defined prefixed commands. The "define" command can
1688 add new commands to existing prefixes, e.g. "target".
1690 * Multi-inferior, multi-process debugging.
1692 GDB now has generalized support for multi-inferior debugging. See
1693 "Debugging Multiple Inferiors" in the manual for more information.
1694 Although availability still depends on target support, the command
1695 set is more uniform now. The GNU/Linux specific multi-forks support
1696 has been migrated to this new framework. This implied some user
1697 visible changes; see "New commands" and also "Removed commands"
1700 * Target descriptions can now describe the target OS ABI. See the
1701 "Target Description Format" section in the user manual for more
1704 * Target descriptions can now describe "compatible" architectures
1705 to indicate that the target can execute applications for a different
1706 architecture in addition to those for the main target architecture.
1707 See the "Target Description Format" section in the user manual for
1710 * Multi-architecture debugging.
1712 GDB now includes general supports for debugging applications on
1713 hybrid systems that use more than one single processor architecture
1714 at the same time. Each such hybrid architecture still requires
1715 specific support to be added. The only hybrid architecture supported
1716 in this version of GDB is the Cell Broadband Engine.
1718 * GDB now supports integrated debugging of Cell/B.E. applications that
1719 use both the PPU and SPU architectures. To enable support for hybrid
1720 Cell/B.E. debugging, you need to configure GDB to support both the
1721 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1722 --enable-targets configure option.
1724 * Non-stop mode debugging.
1726 For some targets, GDB now supports an optional mode of operation in
1727 which you can examine stopped threads while other threads continue
1728 to execute freely. This is referred to as non-stop mode, with the
1729 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1730 section in the user manual for more information.
1732 To be able to support remote non-stop debugging, a remote stub needs
1733 to implement the non-stop mode remote protocol extensions, as
1734 described in the "Remote Non-Stop" section of the user manual. The
1735 GDB remote stub, gdbserver, has been adjusted to support these
1736 extensions on linux targets.
1738 * New commands (for set/show, see "New options" below)
1740 catch syscall [NAME(S) | NUMBER(S)]
1741 Catch system calls. Arguments, which should be names of system
1742 calls or their numbers, mean catch only those syscalls. Without
1743 arguments, every syscall will be caught. When the inferior issues
1744 any of the specified syscalls, GDB will stop and announce the system
1745 call, both when it is called and when its call returns. This
1746 feature is currently available with a native GDB running on the
1747 Linux Kernel, under the following architectures: x86, x86_64,
1748 PowerPC and PowerPC64.
1750 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1752 Search memory for a sequence of bytes.
1754 maint set python print-stack
1755 maint show python print-stack
1756 Show a stack trace when an error is encountered in a Python script.
1759 Invoke CODE by passing it to the Python interpreter.
1764 These allow macros to be defined, undefined, and listed
1768 Show operating system information about processes.
1771 List the inferiors currently under GDB's control.
1774 Switch focus to inferior number NUM.
1777 Detach from inferior number NUM.
1780 Kill inferior number NUM.
1784 set spu stop-on-load
1785 show spu stop-on-load
1786 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1788 set spu auto-flush-cache
1789 show spu auto-flush-cache
1790 Control whether to automatically flush the software-managed cache
1791 during Cell/B.E. debugging.
1793 set sh calling-convention
1794 show sh calling-convention
1795 Control the calling convention used when calling SH target functions.
1798 show debug timestamp
1799 Control display of timestamps with GDB debugging output.
1801 set disassemble-next-line
1802 show disassemble-next-line
1803 Control display of disassembled source lines or instructions when
1806 set remote noack-packet
1807 show remote noack-packet
1808 Set/show the use of remote protocol QStartNoAckMode packet. See above
1809 under "New remote packets."
1811 set remote query-attached-packet
1812 show remote query-attached-packet
1813 Control use of remote protocol `qAttached' (query-attached) packet.
1815 set remote read-siginfo-object
1816 show remote read-siginfo-object
1817 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1820 set remote write-siginfo-object
1821 show remote write-siginfo-object
1822 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1825 set remote reverse-continue
1826 show remote reverse-continue
1827 Control use of remote protocol 'bc' (reverse-continue) packet.
1829 set remote reverse-step
1830 show remote reverse-step
1831 Control use of remote protocol 'bs' (reverse-step) packet.
1833 set displaced-stepping
1834 show displaced-stepping
1835 Control displaced stepping mode. Displaced stepping is a way to
1836 single-step over breakpoints without removing them from the debuggee.
1837 Also known as "out-of-line single-stepping".
1840 show debug displaced
1841 Control display of debugging info for displaced stepping.
1843 maint set internal-error
1844 maint show internal-error
1845 Control what GDB does when an internal error is detected.
1847 maint set internal-warning
1848 maint show internal-warning
1849 Control what GDB does when an internal warning is detected.
1854 Use a wrapper program to launch programs for debugging.
1856 set multiple-symbols (all|ask|cancel)
1857 show multiple-symbols
1858 The value of this variable can be changed to adjust the debugger behavior
1859 when an expression or a breakpoint location contains an ambiguous symbol
1860 name (an overloaded function name, for instance).
1862 set breakpoint always-inserted
1863 show breakpoint always-inserted
1864 Keep breakpoints always inserted in the target, as opposed to inserting
1865 them when resuming the target, and removing them when the target stops.
1866 This option can improve debugger performance on slow remote targets.
1868 set arm fallback-mode (arm|thumb|auto)
1869 show arm fallback-mode
1870 set arm force-mode (arm|thumb|auto)
1872 These commands control how ARM GDB determines whether instructions
1873 are ARM or Thumb. The default for both settings is auto, which uses
1874 the current CPSR value for instructions without symbols; previous
1875 versions of GDB behaved as if "set arm fallback-mode arm".
1877 set disable-randomization
1878 show disable-randomization
1879 Standalone programs run with the virtual address space randomization enabled
1880 by default on some platforms. This option keeps the addresses stable across
1881 multiple debugging sessions.
1885 Control whether other threads are stopped or not when some thread hits
1890 Requests that asynchronous execution is enabled in the target, if available.
1891 In this case, it's possible to resume target in the background, and interact
1892 with GDB while the target is running. "show target-async" displays the
1893 current state of asynchronous execution of the target.
1895 set target-wide-charset
1896 show target-wide-charset
1897 The target-wide-charset is the name of the character set that GDB
1898 uses when printing characters whose type is wchar_t.
1900 set tcp auto-retry (on|off)
1902 set tcp connect-timeout
1903 show tcp connect-timeout
1904 These commands allow GDB to retry failed TCP connections to a remote stub
1905 with a specified timeout period; this is useful if the stub is launched
1906 in parallel with GDB but may not be ready to accept connections immediately.
1908 set libthread-db-search-path
1909 show libthread-db-search-path
1910 Control list of directories which GDB will search for appropriate
1913 set schedule-multiple (on|off)
1914 show schedule-multiple
1915 Allow GDB to resume all threads of all processes or only threads of
1916 the current process.
1920 Use more aggressive caching for accesses to the stack. This improves
1921 performance of remote debugging (particularly backtraces) without
1922 affecting correctness.
1924 set interactive-mode (on|off|auto)
1925 show interactive-mode
1926 Control whether GDB runs in interactive mode (on) or not (off).
1927 When in interactive mode, GDB waits for the user to answer all
1928 queries. Otherwise, GDB does not wait and assumes the default
1929 answer. When set to auto (the default), GDB determines which
1930 mode to use based on the stdin settings.
1935 For program forks, this is replaced by the new more generic `info
1936 inferiors' command. To list checkpoints, you can still use the
1937 `info checkpoints' command, which was an alias for the `info forks'
1941 Replaced by the new `inferior' command. To switch between
1942 checkpoints, you can still use the `restart' command, which was an
1943 alias for the `fork' command.
1946 This is removed, since some targets don't have a notion of
1947 processes. To switch between processes, you can still use the
1948 `inferior' command using GDB's own inferior number.
1951 For program forks, this is replaced by the new more generic `kill
1952 inferior' command. To delete a checkpoint, you can still use the
1953 `delete checkpoint' command, which was an alias for the `delete
1957 For program forks, this is replaced by the new more generic `detach
1958 inferior' command. To detach a checkpoint, you can still use the
1959 `detach checkpoint' command, which was an alias for the `detach
1962 * New native configurations
1964 x86/x86_64 Darwin i[34567]86-*-darwin*
1966 x86_64 MinGW x86_64-*-mingw*
1970 Lattice Mico32 lm32-*
1971 x86 DICOS i[34567]86-*-dicos*
1972 x86_64 DICOS x86_64-*-dicos*
1975 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1976 (mingw32ce) debugging.
1982 These commands were actually not implemented on any target.
1984 *** Changes in GDB 6.8
1986 * New native configurations
1988 NetBSD/hppa hppa*-*netbsd*
1989 Xtensa GNU/Linux xtensa*-*-linux*
1993 NetBSD/hppa hppa*-*-netbsd*
1994 Xtensa GNU/Lunux xtensa*-*-linux*
1996 * Change in command line behavior -- corefiles vs. process ids.
1998 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1999 attaching to process NUMBER fails, GDB no longer attempts to open a
2000 core file named NUMBER. Attaching to a program using the -c option
2001 is no longer supported. Instead, use the '-p' or '--pid' options.
2003 * GDB can now be built as a native debugger for debugging Windows x86
2004 (mingw32) Portable Executable (PE) programs.
2006 * Pending breakpoints no longer change their number when their address
2009 * GDB now supports breakpoints with multiple locations,
2010 including breakpoints on C++ constructors, inside C++ templates,
2011 and in inlined functions.
2013 * GDB's ability to debug optimized code has been improved. GDB more
2014 accurately identifies function bodies and lexical blocks that occupy
2015 more than one contiguous range of addresses.
2017 * Target descriptions can now describe registers for PowerPC.
2019 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2020 registers on PowerPC targets.
2022 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2023 targets even when the libthread_db library is not available.
2025 * The GDB remote stub, gdbserver, now supports the new file transfer
2026 commands (remote put, remote get, and remote delete).
2028 * The GDB remote stub, gdbserver, now supports run and attach in
2029 extended-remote mode.
2031 * hppa*64*-*-hpux11* target broken
2032 The debugger is unable to start a program and fails with the following
2033 error: "Error trying to get information about dynamic linker".
2034 The gdb-6.7 release is also affected.
2036 * GDB now supports the --enable-targets= configure option to allow
2037 building a single GDB executable that supports multiple remote
2038 target architectures.
2040 * GDB now supports debugging C and C++ programs which use the
2041 Decimal Floating Point extension. In addition, the PowerPC target
2042 now has a set of pseudo-registers to inspect decimal float values
2043 stored in two consecutive float registers.
2045 * The -break-insert MI command can optionally create pending
2048 * Improved support for debugging Ada
2049 Many improvements to the Ada language support have been made. These
2051 - Better support for Ada2005 interface types
2052 - Improved handling of arrays and slices in general
2053 - Better support for Taft-amendment types
2054 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2056 - Improved command completion in Ada
2059 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2064 set print frame-arguments (all|scalars|none)
2065 show print frame-arguments
2066 The value of this variable can be changed to control which argument
2067 values should be printed by the debugger when displaying a frame.
2072 Transfer files to and from a remote target, and delete remote files.
2079 Transfer files to and from a remote target, and delete remote files.
2081 * New remote packets
2088 Open, close, read, write, and delete files on the remote system.
2091 Attach to an existing process on the remote system, in extended-remote
2095 Run a new process on the remote system, in extended-remote mode.
2097 *** Changes in GDB 6.7
2099 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2100 bfd, libiberty and opcodes, as revealed by static analysis donated by
2101 Coverity, Inc. (http://scan.coverity.com).
2103 * When looking up multiply-defined global symbols, GDB will now prefer the
2104 symbol definition in the current shared library if it was built using the
2105 -Bsymbolic linker option.
2107 * When the Text User Interface (TUI) is not configured, GDB will now
2108 recognize the -tui command-line option and print a message that the TUI
2111 * The GDB remote stub, gdbserver, now has lower overhead for high
2112 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2114 * GDB for MIPS targets now autodetects whether a remote target provides
2115 32-bit or 64-bit register values.
2117 * Support for C++ member pointers has been improved.
2119 * GDB now understands XML target descriptions, which specify the
2120 target's overall architecture. GDB can read a description from
2121 a local file or over the remote serial protocol.
2123 * Vectors of single-byte data use a new integer type which is not
2124 automatically displayed as character or string data.
2126 * The /s format now works with the print command. It displays
2127 arrays of single-byte integers and pointers to single-byte integers
2130 * Target descriptions can now describe target-specific registers,
2131 for architectures which have implemented the support (currently
2132 only ARM, M68K, and MIPS).
2134 * GDB and the GDB remote stub, gdbserver, now support the XScale
2137 * The GDB remote stub, gdbserver, has been updated to support
2138 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2139 has been rewritten to use the standard GDB remote protocol.
2141 * GDB can now step into C++ functions which are called through thunks.
2143 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2145 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2146 layout. It also supports a TextSeg= and DataSeg= response when only
2147 segment base addresses (rather than offsets) are available.
2149 * The /i format now outputs any trailing branch delay slot instructions
2150 immediately following the last instruction within the count specified.
2152 * The GDB remote protocol "T" stop reply packet now supports a
2153 "library" response. Combined with the new "qXfer:libraries:read"
2154 packet, this response allows GDB to debug shared libraries on targets
2155 where the operating system manages the list of loaded libraries (e.g.
2156 Windows and SymbianOS).
2158 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2159 (DLLs) on Windows and Windows CE targets.
2161 * GDB now supports a faster verification that a .debug file matches its binary
2162 according to its build-id signature, if the signature is present.
2168 Enable or disable hardware flow control (RTS/CTS) on the serial port
2169 when debugging using remote targets.
2171 set mem inaccessible-by-default
2172 show mem inaccessible-by-default
2173 If the target supplies a memory map, for instance via the remote
2174 protocol's "qXfer:memory-map:read" packet, setting this variable
2175 prevents GDB from accessing memory outside the memory map. This
2176 is useful for targets with memory mapped registers or which react
2177 badly to accesses of unmapped address space.
2179 set breakpoint auto-hw
2180 show breakpoint auto-hw
2181 If the target supplies a memory map, for instance via the remote
2182 protocol's "qXfer:memory-map:read" packet, setting this variable
2183 lets GDB use hardware breakpoints automatically for memory regions
2184 where it can not use software breakpoints. This covers both the
2185 "break" command and internal breakpoints used for other commands
2186 including "next" and "finish".
2189 catch exception unhandled
2190 Stop the program execution when Ada exceptions are raised.
2193 Stop the program execution when an Ada assertion failed.
2197 Set an alternate system root for target files. This is a more
2198 general version of "set solib-absolute-prefix", which is now
2199 an alias to "set sysroot".
2202 Provide extended SPU facility status information. This set of
2203 commands is available only when debugging the Cell/B.E. SPU
2206 * New native configurations
2208 OpenBSD/sh sh*-*openbsd*
2211 unset tdesc filename
2213 Use the specified local file as an XML target description, and do
2214 not query the target for its built-in description.
2218 OpenBSD/sh sh*-*-openbsd*
2219 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2220 Toshiba Media Processor mep-elf
2222 * New remote packets
2225 Ignore the specified signals; pass them directly to the debugged program
2226 without stopping other threads or reporting them to GDB.
2228 qXfer:features:read:
2229 Read an XML target description from the target, which describes its
2234 Read or write contents of an spufs file on the target system. These
2235 packets are available only on the Cell/B.E. SPU architecture.
2237 qXfer:libraries:read:
2238 Report the loaded shared libraries. Combined with new "T" packet
2239 response, this packet allows GDB to debug shared libraries on
2240 targets where the operating system manages the list of loaded
2241 libraries (e.g. Windows and SymbianOS).
2245 Support for these obsolete configurations has been removed.
2253 i[34567]86-*-lynxos*
2254 i[34567]86-*-netware*
2255 i[34567]86-*-sco3.2v5*
2256 i[34567]86-*-sco3.2v4*
2258 i[34567]86-*-sysv4.2*
2261 i[34567]86-*-unixware2*
2262 i[34567]86-*-unixware*
2271 * Other removed features
2278 Various m68k-only ROM monitors.
2285 Various Renesas ROM monitors and debugging interfaces for SH and
2290 Support for a Macraigor serial interface to on-chip debugging.
2291 GDB does not directly support the newer parallel or USB
2296 A debug information format. The predecessor to DWARF 2 and
2297 DWARF 3, which are still supported.
2299 Support for the HP aCC compiler on HP-UX/PA-RISC
2301 SOM-encapsulated symbolic debugging information, automatic
2302 invocation of pxdb, and the aCC custom C++ ABI. This does not
2303 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2304 with aCC can still be debugged on an assembly level.
2306 MIPS ".pdr" sections
2308 A MIPS-specific format used to describe stack frame layout
2309 in debugging information.
2313 GDB could work with an older version of Guile to debug
2314 the interpreter and Scheme programs running in it.
2316 set mips stack-arg-size
2317 set mips saved-gpreg-size
2319 Use "set mips abi" to control parameter passing for MIPS.
2321 *** Changes in GDB 6.6
2326 Cell Broadband Engine SPU spu-elf
2328 * GDB can now be configured as a cross-debugger targeting native Windows
2329 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2330 running on a Windows system over TCP/IP to debug Windows programs.
2332 * The GDB remote stub, gdbserver, has been updated to support Windows and
2333 Cygwin debugging. Both single-threaded and multi-threaded programs are
2336 * The "set trust-readonly-sections" command works again. This command was
2337 broken in GDB 6.3, 6.4, and 6.5.
2339 * The "load" command now supports writing to flash memory, if the remote
2340 stub provides the required support.
2342 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2343 longer requires symbolic debug information (e.g. DWARF-2).
2348 unset substitute-path
2349 show substitute-path
2350 Manage a list of substitution rules that GDB uses to rewrite the name
2351 of the directories where the sources are located. This can be useful
2352 for instance when the sources were moved to a different location
2353 between compilation and debugging.
2357 Print each CLI command as it is executed. Each command is prefixed with
2358 a number of `+' symbols representing the nesting depth.
2359 The source command now has a `-v' option to enable the same feature.
2363 The ARM Demon monitor support (RDP protocol, "target rdp").
2365 Kernel Object Display, an embedded debugging feature which only worked with
2366 an obsolete version of Cisco IOS.
2368 The 'set download-write-size' and 'show download-write-size' commands.
2370 * New remote packets
2373 Tell a stub about GDB client features, and request remote target features.
2374 The first feature implemented is PacketSize, which allows the target to
2375 specify the size of packets it can handle - to minimize the number of
2376 packets required and improve performance when connected to a remote
2380 Fetch an OS auxilliary vector from the remote stub. This packet is a
2381 more efficient replacement for qPart:auxv:read.
2383 qXfer:memory-map:read:
2384 Fetch a memory map from the remote stub, including information about
2385 RAM, ROM, and flash memory devices.
2390 Erase and program a flash memory device.
2392 * Removed remote packets
2395 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2396 used it, and only gdbserver implemented it.
2398 *** Changes in GDB 6.5
2402 Renesas M32C/M16C m32c-elf
2404 Morpho Technologies ms1 ms1-elf
2408 init-if-undefined Initialize a convenience variable, but
2409 only if it doesn't already have a value.
2411 The following commands are presently only implemented for native GNU/Linux:
2413 checkpoint Save a snapshot of the program state.
2415 restart <n> Return the program state to a
2416 previously saved state.
2418 info checkpoints List currently saved checkpoints.
2420 delete-checkpoint <n> Delete a previously saved checkpoint.
2422 set|show detach-on-fork Tell gdb whether to detach from a newly
2423 forked process, or to keep debugging it.
2425 info forks List forks of the user program that
2426 are available to be debugged.
2428 fork <n> Switch to debugging one of several
2429 forks of the user program that are
2430 available to be debugged.
2432 delete-fork <n> Delete a fork from the list of forks
2433 that are available to be debugged (and
2434 kill the forked process).
2436 detach-fork <n> Delete a fork from the list of forks
2437 that are available to be debugged (and
2438 allow the process to continue).
2442 Morpho Technologies ms2 ms1-elf
2444 * Improved Windows host support
2446 GDB now builds as a cross debugger hosted on i686-mingw32, including
2447 native console support, and remote communications using either
2448 network sockets or serial ports.
2450 * Improved Modula-2 language support
2452 GDB can now print most types in the Modula-2 syntax. This includes:
2453 basic types, set types, record types, enumerated types, range types,
2454 pointer types and ARRAY types. Procedure var parameters are correctly
2455 printed and hexadecimal addresses and character constants are also
2456 written in the Modula-2 syntax. Best results can be obtained by using
2457 GNU Modula-2 together with the -gdwarf-2 command line option.
2461 The ARM rdi-share module.
2463 The Netware NLM debug server.
2465 *** Changes in GDB 6.4
2467 * New native configurations
2469 OpenBSD/arm arm*-*-openbsd*
2470 OpenBSD/mips64 mips64-*-openbsd*
2474 Morpho Technologies ms1 ms1-elf
2476 * New command line options
2478 --batch-silent As for --batch, but totally silent.
2479 --return-child-result The debugger will exist with the same value
2480 the child (debugged) program exited with.
2481 --eval-command COMMAND, -ex COMMAND
2482 Execute a single GDB CLI command. This may be
2483 specified multiple times and in conjunction
2484 with the --command (-x) option.
2486 * Deprecated commands removed
2488 The following commands, that were deprecated in 2000, have been
2492 set|show arm disassembly-flavor set|show arm disassembler
2493 othernames set arm disassembler
2494 set|show remotedebug set|show debug remote
2495 set|show archdebug set|show debug arch
2496 set|show eventdebug set|show debug event
2499 * New BSD user-level threads support
2501 It is now possible to debug programs using the user-level threads
2502 library on OpenBSD and FreeBSD. Currently supported (target)
2505 FreeBSD/amd64 x86_64-*-freebsd*
2506 FreeBSD/i386 i386-*-freebsd*
2507 OpenBSD/i386 i386-*-openbsd*
2509 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2510 are not yet supported.
2512 * New support for Matsushita MN10300 w/sim added
2513 (Work in progress). mn10300-elf.
2515 * REMOVED configurations and files
2517 VxWorks and the XDR protocol *-*-vxworks
2518 Motorola MCORE mcore-*-*
2519 National Semiconductor NS32000 ns32k-*-*
2521 * New "set print array-indexes" command
2523 After turning this setting "on", GDB prints the index of each element
2524 when displaying arrays. The default is "off" to preserve the previous
2527 * VAX floating point support
2529 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2531 * User-defined command support
2533 In addition to using $arg0..$arg9 for argument passing, it is now possible
2534 to use $argc to determine now many arguments have been passed. See the
2535 section on user-defined commands in the user manual for more information.
2537 *** Changes in GDB 6.3:
2539 * New command line option
2541 GDB now accepts -l followed by a number to set the timeout for remote
2544 * GDB works with GCC -feliminate-dwarf2-dups
2546 GDB now supports a more compact representation of DWARF-2 debug
2547 information using DW_FORM_ref_addr references. These are produced
2548 by GCC with the option -feliminate-dwarf2-dups and also by some
2549 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2550 to use -feliminate-dwarf2-dups.
2552 * Internationalization
2554 When supported by the host system, GDB will be built with
2555 internationalization (libintl). The task of marking up the sources is
2556 continued, we're looking forward to our first translation.
2560 Initial support for debugging programs compiled with the GNAT
2561 implementation of the Ada programming language has been integrated
2562 into GDB. In this release, support is limited to expression evaluation.
2564 * New native configurations
2566 GNU/Linux/m32r m32r-*-linux-gnu
2570 GDB's remote protocol now includes support for the 'p' packet. This
2571 packet is used to fetch individual registers from a remote inferior.
2573 * END-OF-LIFE registers[] compatibility module
2575 GDB's internal register infrastructure has been completely rewritten.
2576 The new infrastructure making possible the implementation of key new
2577 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2580 GDB 6.3 will be the last release to include the the registers[]
2581 compatibility module that allowed out-of-date configurations to
2582 continue to work. This change directly impacts the following
2592 powerpc bdm protocol
2594 Unless there is activity to revive these configurations, they will be
2595 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2597 * OBSOLETE configurations and files
2599 Configurations that have been declared obsolete in this release have
2600 been commented out. Unless there is activity to revive these
2601 configurations, the next release of GDB will have their sources
2602 permanently REMOVED.
2611 *** Changes in GDB 6.2.1:
2613 * MIPS `break main; run' gave an heuristic-fence-post warning
2615 When attempting to run even a simple program, a warning about
2616 heuristic-fence-post being hit would be reported. This problem has
2619 * MIPS IRIX 'long double' crashed GDB
2621 When examining a long double variable, GDB would get a segmentation
2622 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2623 IRIX long double values).
2627 A bug in the VAX stack code was causing problems with the "next"
2628 command. This problem has been fixed.
2630 *** Changes in GDB 6.2:
2632 * Fix for ``many threads''
2634 On GNU/Linux systems that use the NPTL threads library, a program
2635 rapidly creating and deleting threads would confuse GDB leading to the
2638 ptrace: No such process.
2639 thread_db_get_info: cannot get thread info: generic error
2641 This problem has been fixed.
2643 * "-async" and "-noasync" options removed.
2645 Support for the broken "-noasync" option has been removed (it caused
2648 * New ``start'' command.
2650 This command runs the program until the begining of the main procedure.
2652 * New BSD Kernel Data Access Library (libkvm) interface
2654 Using ``target kvm'' it is now possible to debug kernel core dumps and
2655 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2656 platforms. Currently supported (native-only) configurations are:
2658 FreeBSD/amd64 x86_64-*-freebsd*
2659 FreeBSD/i386 i?86-*-freebsd*
2660 NetBSD/i386 i?86-*-netbsd*
2661 NetBSD/m68k m68*-*-netbsd*
2662 NetBSD/sparc sparc-*-netbsd*
2663 OpenBSD/amd64 x86_64-*-openbsd*
2664 OpenBSD/i386 i?86-*-openbsd*
2665 OpenBSD/m68k m68*-openbsd*
2666 OpenBSD/sparc sparc-*-openbsd*
2668 * Signal trampoline code overhauled
2670 Many generic problems with GDB's signal handling code have been fixed.
2671 These include: backtraces through non-contiguous stacks; recognition
2672 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2673 call; backtrace through a signal trampoline; step into and out of
2674 signal handlers; and single-stepping in the signal trampoline.
2676 Please note that kernel bugs are a limiting factor here. These
2677 features have been shown to work on an s390 GNU/Linux system that
2678 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2680 * Cygwin support for DWARF 2 added.
2682 * New native configurations
2684 GNU/Linux/hppa hppa*-*-linux*
2685 OpenBSD/hppa hppa*-*-openbsd*
2686 OpenBSD/m68k m68*-*-openbsd*
2687 OpenBSD/m88k m88*-*-openbsd*
2688 OpenBSD/powerpc powerpc-*-openbsd*
2689 NetBSD/vax vax-*-netbsd*
2690 OpenBSD/vax vax-*-openbsd*
2692 * END-OF-LIFE frame compatibility module
2694 GDB's internal frame infrastructure has been completely rewritten.
2695 The new infrastructure making it possible to support key new features
2696 including DWARF 2 Call Frame Information. To aid in the task of
2697 migrating old configurations to this new infrastructure, a
2698 compatibility module, that allowed old configurations to continue to
2699 work, was also included.
2701 GDB 6.2 will be the last release to include this frame compatibility
2702 module. This change directly impacts the following configurations:
2712 Unless there is activity to revive these configurations, they will be
2713 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2715 * REMOVED configurations and files
2717 Sun 3, running SunOS 3 m68*-*-sunos3*
2718 Sun 3, running SunOS 4 m68*-*-sunos4*
2719 Sun 2, running SunOS 3 m68000-*-sunos3*
2720 Sun 2, running SunOS 4 m68000-*-sunos4*
2721 Motorola 680x0 running LynxOS m68*-*-lynxos*
2722 AT&T 3b1/Unix pc m68*-att-*
2723 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2724 decstation mips-dec-* mips-little-*
2725 riscos mips-*-riscos* mips-*-sysv*
2726 sonymips mips-sony-*
2727 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2729 *** Changes in GDB 6.1.1:
2731 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2733 The TUI (Text-mode User Interface) is now built as part of a default
2734 GDB configuration. It is enabled by either selecting the TUI with the
2735 command line option "-i=tui" or by running the separate "gdbtui"
2736 program. For more information on the TUI, see the manual "Debugging
2739 * Pending breakpoint support (also included in GDB 6.1)
2741 Support has been added to allow you to specify breakpoints in shared
2742 libraries that have not yet been loaded. If a breakpoint location
2743 cannot be found, and the "breakpoint pending" option is set to auto,
2744 GDB queries you if you wish to make the breakpoint pending on a future
2745 shared-library load. If and when GDB resolves the breakpoint symbol,
2746 the pending breakpoint is removed as one or more regular breakpoints
2749 Pending breakpoints are very useful for GCJ Java debugging.
2751 * Fixed ISO-C build problems
2753 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2754 non ISO-C code that stopped them being built using a more strict ISO-C
2755 compiler (e.g., IBM's C compiler).
2757 * Fixed build problem on IRIX 5
2759 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2760 wasn't able to compile compile on an IRIX 5 system.
2762 * Added execute permission to gdb/gdbserver/configure
2764 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2765 permission. This bug would cause configure to fail on a number of
2766 systems (Solaris, IRIX). Ref: server/519.
2768 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2770 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2771 has been updated to use constant array sizes.
2773 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2775 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2776 its generated DWARF Call Frame Info. This encoding was causing GDB to
2777 panic, that panic has been fixed. Ref: gdb/1628.
2779 * Fixed a problem when examining parameters in shared library code.
2781 When examining parameters in optimized shared library code generated
2782 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2783 not available''. GDB now correctly displays the variable's value.
2785 *** Changes in GDB 6.1:
2787 * Removed --with-mmalloc
2789 Support for the mmalloc memory manager has been removed, as it
2790 conflicted with the internal gdb byte cache.
2792 * Changes in AMD64 configurations
2794 The AMD64 target now includes the %cs and %ss registers. As a result
2795 the AMD64 remote protocol has changed; this affects the floating-point
2796 and SSE registers. If you rely on those registers for your debugging,
2797 you should upgrade gdbserver on the remote side.
2799 * Revised SPARC target
2801 The SPARC target has been completely revised, incorporating the
2802 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2803 support for LynxOS and SunOS 4 has been dropped. Calling functions
2804 from within GDB on operating systems with a non-executable stack
2805 (Solaris, OpenBSD) now works.
2809 GDB has a new C++ demangler which does a better job on the mangled
2810 names generated by current versions of g++. It also runs faster, so
2811 with this and other changes gdb should now start faster on large C++
2814 * DWARF 2 Location Expressions
2816 GDB support for location expressions has been extended to support function
2817 arguments and frame bases. Older versions of GDB could crash when they
2820 * C++ nested types and namespaces
2822 GDB's support for nested types and namespaces in C++ has been
2823 improved, especially if you use the DWARF 2 debugging format. (This
2824 is the default for recent versions of GCC on most platforms.)
2825 Specifically, if you have a class "Inner" defined within a class or
2826 namespace "Outer", then GDB realizes that the class's name is
2827 "Outer::Inner", not simply "Inner". This should greatly reduce the
2828 frequency of complaints about not finding RTTI symbols. In addition,
2829 if you are stopped at inside of a function defined within a namespace,
2830 GDB modifies its name lookup accordingly.
2832 * New native configurations
2834 NetBSD/amd64 x86_64-*-netbsd*
2835 OpenBSD/amd64 x86_64-*-openbsd*
2836 OpenBSD/alpha alpha*-*-openbsd*
2837 OpenBSD/sparc sparc-*-openbsd*
2838 OpenBSD/sparc64 sparc64-*-openbsd*
2840 * New debugging protocols
2842 M32R with SDI protocol m32r-*-elf*
2844 * "set prompt-escape-char" command deleted.
2846 The command "set prompt-escape-char" has been deleted. This command,
2847 and its very obscure effet on GDB's prompt, was never documented,
2848 tested, nor mentioned in the NEWS file.
2850 * OBSOLETE configurations and files
2852 Configurations that have been declared obsolete in this release have
2853 been commented out. Unless there is activity to revive these
2854 configurations, the next release of GDB will have their sources
2855 permanently REMOVED.
2857 Sun 3, running SunOS 3 m68*-*-sunos3*
2858 Sun 3, running SunOS 4 m68*-*-sunos4*
2859 Sun 2, running SunOS 3 m68000-*-sunos3*
2860 Sun 2, running SunOS 4 m68000-*-sunos4*
2861 Motorola 680x0 running LynxOS m68*-*-lynxos*
2862 AT&T 3b1/Unix pc m68*-att-*
2863 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2864 decstation mips-dec-* mips-little-*
2865 riscos mips-*-riscos* mips-*-sysv*
2866 sonymips mips-sony-*
2867 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2869 * REMOVED configurations and files
2871 SGI Irix-4.x mips-sgi-irix4 or iris4
2872 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2873 Z8000 simulator z8k-zilog-none or z8ksim
2874 Matsushita MN10200 w/simulator mn10200-*-*
2875 H8/500 simulator h8500-hitachi-hms or h8500hms
2876 HP/PA running BSD hppa*-*-bsd*
2877 HP/PA running OSF/1 hppa*-*-osf*
2878 HP/PA Pro target hppa*-*-pro*
2879 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2880 386BSD i[3456]86-*-bsd*
2881 Sequent family i[3456]86-sequent-sysv4*
2882 i[3456]86-sequent-sysv*
2883 i[3456]86-sequent-bsd*
2884 SPARC running LynxOS sparc-*-lynxos*
2885 SPARC running SunOS 4 sparc-*-sunos4*
2886 Tsqware Sparclet sparclet-*-*
2887 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2889 *** Changes in GDB 6.0:
2893 Support for debugging the Objective-C programming language has been
2894 integrated into GDB.
2896 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2898 DWARF 2's Call Frame Information makes available compiler generated
2899 information that more exactly describes the program's run-time stack.
2900 By using this information, GDB is able to provide more robust stack
2903 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2904 have been updated to use a new backtrace mechanism which includes
2905 DWARF 2 CFI support.
2909 GDB's remote protocol has been extended to include support for hosted
2910 file I/O (where the remote target uses GDB's file system). See GDB's
2911 remote protocol documentation for details.
2913 * All targets using the new architecture framework.
2915 All of GDB's targets have been updated to use the new internal
2916 architecture framework. The way is now open for future GDB releases
2917 to include cross-architecture native debugging support (i386 on amd64,
2920 * GNU/Linux's Thread Local Storage (TLS)
2922 GDB now includes support for for the GNU/Linux implementation of
2923 per-thread variables.
2925 * GNU/Linux's Native POSIX Thread Library (NPTL)
2927 GDB's thread code has been updated to work with either the new
2928 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2930 * Separate debug info.
2932 GDB, in conjunction with BINUTILS, now supports a mechanism for
2933 automatically loading debug information from a separate file. Instead
2934 of shipping full debug and non-debug versions of system libraries,
2935 system integrators can now instead ship just the stripped libraries
2936 and optional debug files.
2938 * DWARF 2 Location Expressions
2940 DWARF 2 Location Expressions allow the compiler to more completely
2941 describe the location of variables (even in optimized code) to the
2944 GDB now includes preliminary support for location expressions (support
2945 for DW_OP_piece is still missing).
2949 A number of long standing bugs that caused GDB to die while starting a
2950 Java application have been fixed. GDB's Java support is now
2951 considered "useable".
2953 * GNU/Linux support for fork, vfork, and exec.
2955 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2956 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2959 * GDB supports logging output to a file
2961 There are two new commands, "set logging" and "show logging", which can be
2962 used to capture GDB's output to a file.
2964 * The meaning of "detach" has changed for gdbserver
2966 The "detach" command will now resume the application, as documented. To
2967 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2970 * d10v, m68hc11 `regs' command deprecated
2972 The `info registers' command has been updated so that it displays the
2973 registers using a format identical to the old `regs' command.
2977 A new command, "maint set profile on/off", has been added. This command can
2978 be used to enable or disable profiling while running GDB, to profile a
2979 session or a set of commands. In addition there is a new configure switch,
2980 "--enable-profiling", which will cause GDB to be compiled with profiling
2981 data, for more informative profiling results.
2983 * Default MI syntax changed to "mi2".
2985 The default MI (machine interface) syntax, enabled by the command line
2986 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2987 "mi1", can be enabled by specifying the option "-i=mi1".
2989 Support for the original "mi0" syntax (included in GDB 5.0) has been
2992 Fix for gdb/192: removed extraneous space when displaying frame level.
2993 Fix for gdb/672: update changelist is now output in mi list format.
2994 Fix for gdb/702: a -var-assign that updates the value now shows up
2995 in a subsequent -var-update.
2997 * New native configurations.
2999 FreeBSD/amd64 x86_64-*-freebsd*
3001 * Multi-arched targets.
3003 HP/PA HPUX11 hppa*-*-hpux*
3004 Renesas M32R/D w/simulator m32r-*-elf*
3006 * OBSOLETE configurations and files
3008 Configurations that have been declared obsolete in this release have
3009 been commented out. Unless there is activity to revive these
3010 configurations, the next release of GDB will have their sources
3011 permanently REMOVED.
3013 Z8000 simulator z8k-zilog-none or z8ksim
3014 Matsushita MN10200 w/simulator mn10200-*-*
3015 H8/500 simulator h8500-hitachi-hms or h8500hms
3016 HP/PA running BSD hppa*-*-bsd*
3017 HP/PA running OSF/1 hppa*-*-osf*
3018 HP/PA Pro target hppa*-*-pro*
3019 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3020 Sequent family i[3456]86-sequent-sysv4*
3021 i[3456]86-sequent-sysv*
3022 i[3456]86-sequent-bsd*
3023 Tsqware Sparclet sparclet-*-*
3024 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3026 * REMOVED configurations and files
3029 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3030 IBM AIX PS/2 i[3456]86-*-aix
3031 i386 running Mach 3.0 i[3456]86-*-mach3*
3032 i386 running Mach i[3456]86-*-mach*
3033 i386 running OSF/1 i[3456]86-*osf1mk*
3034 HP/Apollo 68k Family m68*-apollo*-sysv*,
3036 m68*-hp-bsd*, m68*-hp-hpux*
3037 Argonaut Risc Chip (ARC) arc-*-*
3038 Mitsubishi D30V d30v-*-*
3039 Fujitsu FR30 fr30-*-elf*
3040 OS/9000 i[34]86-*-os9k
3041 I960 with MON960 i960-*-coff
3043 * MIPS $fp behavior changed
3045 The convenience variable $fp, for the MIPS, now consistently returns
3046 the address of the current frame's base. Previously, depending on the
3047 context, $fp could refer to either $sp or the current frame's base
3048 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3049 The GNU Source-Level Debugger''.
3051 *** Changes in GDB 5.3:
3053 * GNU/Linux shared library multi-threaded performance improved.
3055 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3056 `/proc', in preference to `ptrace' for memory reads. This may result
3057 in an improvement in the start-up time of multi-threaded, shared
3058 library applications when run under GDB. One GDB user writes: ``loads
3059 shared libs like mad''.
3061 * ``gdbserver'' now supports multi-threaded applications on some targets
3063 Support for debugging multi-threaded applications which use
3064 the GNU/Linux LinuxThreads package has been added for
3065 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3066 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3068 * GDB now supports C/C++ preprocessor macros.
3070 GDB now expands preprocessor macro invocations in C/C++ expressions,
3071 and provides various commands for showing macro definitions and how
3074 The new command `macro expand EXPRESSION' expands any macro
3075 invocations in expression, and shows the result.
3077 The new command `show macro MACRO-NAME' shows the definition of the
3078 macro named MACRO-NAME, and where it was defined.
3080 Most compilers don't include information about macros in the debugging
3081 information by default. In GCC 3.1, for example, you need to compile
3082 your program with the options `-gdwarf-2 -g3'. If the macro
3083 information is present in the executable, GDB will read it.
3085 * Multi-arched targets.
3087 DEC Alpha (partial) alpha*-*-*
3088 DEC VAX (partial) vax-*-*
3090 National Semiconductor NS32000 (partial) ns32k-*-*
3091 Motorola 68000 (partial) m68k-*-*
3092 Motorola MCORE mcore-*-*
3096 Fujitsu FRV architecture added by Red Hat frv*-*-*
3099 * New native configurations
3101 Alpha NetBSD alpha*-*-netbsd*
3102 SH NetBSD sh*-*-netbsdelf*
3103 MIPS NetBSD mips*-*-netbsd*
3104 UltraSPARC NetBSD sparc64-*-netbsd*
3106 * OBSOLETE configurations and files
3108 Configurations that have been declared obsolete in this release have
3109 been commented out. Unless there is activity to revive these
3110 configurations, the next release of GDB will have their sources
3111 permanently REMOVED.
3113 Mitsubishi D30V d30v-*-*
3114 OS/9000 i[34]86-*-os9k
3115 IBM AIX PS/2 i[3456]86-*-aix
3116 Fujitsu FR30 fr30-*-elf*
3117 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3118 Argonaut Risc Chip (ARC) arc-*-*
3119 i386 running Mach 3.0 i[3456]86-*-mach3*
3120 i386 running Mach i[3456]86-*-mach*
3121 i386 running OSF/1 i[3456]86-*osf1mk*
3122 HP/Apollo 68k Family m68*-apollo*-sysv*,
3124 m68*-hp-bsd*, m68*-hp-hpux*
3125 I960 with MON960 i960-*-coff
3127 * OBSOLETE languages
3129 CHILL, a Pascal like language used by telecommunications companies.
3131 * REMOVED configurations and files
3133 AMD 29k family via UDI a29k-amd-udi, udi29k
3134 A29K VxWorks a29k-*-vxworks
3135 AMD 29000 embedded, using EBMON a29k-none-none
3136 AMD 29000 embedded with COFF a29k-none-coff
3137 AMD 29000 embedded with a.out a29k-none-aout
3139 testsuite/gdb.hp/gdb.threads-hp/ directory
3141 * New command "set max-user-call-depth <nnn>"
3143 This command allows the user to limit the call depth of user-defined
3144 commands. The default is 1024.
3146 * Changes in FreeBSD/i386 native debugging.
3148 Support for the "generate-core-file" has been added.
3150 * New commands "dump", "append", and "restore".
3152 These commands allow data to be copied from target memory
3153 to a bfd-format or binary file (dump and append), and back
3154 from a file into memory (restore).
3156 * Improved "next/step" support on multi-processor Alpha Tru64.
3158 The previous single-step mechanism could cause unpredictable problems,
3159 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3160 of a software single-step mechanism prevents this.
3162 *** Changes in GDB 5.2.1:
3170 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3171 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3172 Fix, by Joel Brobecker imported from mainline.
3174 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3175 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3176 Fix, by Fred Fish, imported from mainline.
3178 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3179 Surprisingly enough, it works now.
3180 By Michal Ludvig, imported from mainline.
3182 i386 hardware watchpoint support:
3183 avoid misses on second run for some targets.
3184 By Pierre Muller, imported from mainline.
3186 *** Changes in GDB 5.2:
3188 * New command "set trust-readonly-sections on[off]".
3190 This command is a hint that tells gdb that read-only sections
3191 really are read-only (ie. that their contents will not change).
3192 In this mode, gdb will go to the object file rather than the
3193 target to read memory from read-only sections (such as ".text").
3194 This can be a significant performance improvement on some
3195 (notably embedded) targets.
3197 * New command "generate-core-file" (or "gcore").
3199 This new gdb command allows the user to drop a core file of the child
3200 process state at any time. So far it's been implemented only for
3201 GNU/Linux and Solaris, but should be relatively easily ported to other
3202 hosts. Argument is core file name (defaults to core.<pid>).
3204 * New command line option
3206 GDB now accepts --pid or -p followed by a process id.
3208 * Change in command line behavior -- corefiles vs. process ids.
3210 There is a subtle behavior in the way in which GDB handles
3211 command line arguments. The first non-flag argument is always
3212 a program to debug, but the second non-flag argument may either
3213 be a corefile or a process id. Previously, GDB would attempt to
3214 open the second argument as a corefile, and if that failed, would
3215 issue a superfluous error message and then attempt to attach it as
3216 a process. Now, if the second argument begins with a non-digit,
3217 it will be treated as a corefile. If it begins with a digit,
3218 GDB will attempt to attach it as a process, and if no such process
3219 is found, will then attempt to open it as a corefile.
3221 * Changes in ARM configurations.
3223 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3224 configuration is fully multi-arch.
3226 * New native configurations
3228 ARM NetBSD arm*-*-netbsd*
3229 x86 OpenBSD i[3456]86-*-openbsd*
3230 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3231 Sparc64 running FreeBSD sparc64-*-freebsd*
3235 Sanyo XStormy16 xstormy16-elf
3237 * OBSOLETE configurations and files
3239 Configurations that have been declared obsolete in this release have
3240 been commented out. Unless there is activity to revive these
3241 configurations, the next release of GDB will have their sources
3242 permanently REMOVED.
3244 AMD 29k family via UDI a29k-amd-udi, udi29k
3245 A29K VxWorks a29k-*-vxworks
3246 AMD 29000 embedded, using EBMON a29k-none-none
3247 AMD 29000 embedded with COFF a29k-none-coff
3248 AMD 29000 embedded with a.out a29k-none-aout
3250 testsuite/gdb.hp/gdb.threads-hp/ directory
3252 * REMOVED configurations and files
3254 TI TMS320C80 tic80-*-*
3256 PowerPC Solaris powerpcle-*-solaris*
3257 PowerPC Windows NT powerpcle-*-cygwin32
3258 PowerPC Netware powerpc-*-netware*
3259 Harris/CXUX m88k m88*-harris-cxux*
3260 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3261 ns32k-utek-sysv* ns32k-utek-*
3262 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3263 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3264 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3265 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3266 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3268 * Changes to command line processing
3270 The new `--args' feature can be used to specify command-line arguments
3271 for the inferior from gdb's command line.
3273 * Changes to key bindings
3275 There is a new `operate-and-get-next' function bound to `C-o'.
3277 *** Changes in GDB 5.1.1
3279 Fix compile problem on DJGPP.
3281 Fix a problem with floating-point registers on the i386 being
3284 Fix to stop GDB crashing on .debug_str debug info.
3286 Numerous documentation fixes.
3288 Numerous testsuite fixes.
3290 *** Changes in GDB 5.1:
3292 * New native configurations
3294 Alpha FreeBSD alpha*-*-freebsd*
3295 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3296 MIPS GNU/Linux mips*-*-linux*
3297 MIPS SGI Irix 6.x mips*-sgi-irix6*
3298 ia64 AIX ia64-*-aix*
3299 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3303 Motorola 68HC11 and 68HC12 m68hc11-elf
3305 UltraSparc running GNU/Linux sparc64-*-linux*
3307 * OBSOLETE configurations and files
3309 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3310 Harris/CXUX m88k m88*-harris-cxux*
3311 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3312 ns32k-utek-sysv* ns32k-utek-*
3313 TI TMS320C80 tic80-*-*
3315 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3316 PowerPC Solaris powerpcle-*-solaris*
3317 PowerPC Windows NT powerpcle-*-cygwin32
3318 PowerPC Netware powerpc-*-netware*
3319 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3320 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3321 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3322 Apple Macintosh (MPW) host N/A
3324 stuff.c (Program to stuff files into a specially prepared space in kdb)
3325 kdb-start.c (Main loop for the standalone kernel debugger)
3327 Configurations that have been declared obsolete in this release have
3328 been commented out. Unless there is activity to revive these
3329 configurations, the next release of GDB will have their sources
3330 permanently REMOVED.
3332 * REMOVED configurations and files
3334 Altos 3068 m68*-altos-*
3335 Convex c1-*-*, c2-*-*
3337 ARM RISCix arm-*-* (as host)
3341 * GDB has been converted to ISO C.
3343 GDB's source code has been converted to ISO C. In particular, the
3344 sources are fully protoized, and rely on standard headers being
3349 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3351 * The MI enabled by default.
3353 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3354 revised and enabled by default. Packages which use GDB as a debugging
3355 engine behind a UI or another front end are encouraged to switch to
3356 using the GDB/MI interface, instead of the old annotations interface
3357 which is now deprecated.
3359 * Support for debugging Pascal programs.
3361 GDB now includes support for debugging Pascal programs. The following
3362 main features are supported:
3364 - Pascal-specific data types such as sets;
3366 - automatic recognition of Pascal sources based on file-name
3369 - Pascal-style display of data types, variables, and functions;
3371 - a Pascal expression parser.
3373 However, some important features are not yet supported.
3375 - Pascal string operations are not supported at all;
3377 - there are some problems with boolean types;
3379 - Pascal type hexadecimal constants are not supported
3380 because they conflict with the internal variables format;
3382 - support for Pascal objects and classes is not full yet;
3384 - unlike Pascal, GDB is case-sensitive for symbol names.
3386 * Changes in completion.
3388 Commands such as `shell', `run' and `set args', which pass arguments
3389 to inferior programs, now complete on file names, similar to what
3390 users expect at the shell prompt.
3392 Commands which accept locations, such as `disassemble', `print',
3393 `breakpoint', `until', etc. now complete on filenames as well as
3394 program symbols. Thus, if you type "break foob TAB", and the source
3395 files linked into the programs include `foobar.c', that file name will
3396 be one of the candidates for completion. However, file names are not
3397 considered for completion after you typed a colon that delimits a file
3398 name from a name of a function in that file, as in "break foo.c:bar".
3400 `set demangle-style' completes on available demangling styles.
3402 * New platform-independent commands:
3404 It is now possible to define a post-hook for a command as well as a
3405 hook that runs before the command. For more details, see the
3406 documentation of `hookpost' in the GDB manual.
3408 * Changes in GNU/Linux native debugging.
3410 Support for debugging multi-threaded programs has been completely
3411 revised for all platforms except m68k and sparc. You can now debug as
3412 many threads as your system allows you to have.
3414 Attach/detach is supported for multi-threaded programs.
3416 Support for SSE registers was added for x86. This doesn't work for
3417 multi-threaded programs though.
3419 * Changes in MIPS configurations.
3421 Multi-arch support is enabled for all MIPS configurations.
3423 GDB can now be built as native debugger on SGI Irix 6.x systems for
3424 debugging n32 executables. (Debugging 64-bit executables is not yet
3427 * Unified support for hardware watchpoints in all x86 configurations.
3429 Most (if not all) native x86 configurations support hardware-assisted
3430 breakpoints and watchpoints in a unified manner. This support
3431 implements debug register sharing between watchpoints, which allows to
3432 put a virtually infinite number of watchpoints on the same address,
3433 and also supports watching regions up to 16 bytes with several debug
3436 The new maintenance command `maintenance show-debug-regs' toggles
3437 debugging print-outs in functions that insert, remove, and test
3438 watchpoints and hardware breakpoints.
3440 * Changes in the DJGPP native configuration.
3442 New command ``info dos sysinfo'' displays assorted information about
3443 the CPU, OS, memory, and DPMI server.
3445 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3446 display information about segment descriptors stored in GDT, LDT, and
3449 New commands ``info dos pde'' and ``info dos pte'' display entries
3450 from Page Directory and Page Tables (for now works with CWSDPMI only).
3451 New command ``info dos address-pte'' displays the Page Table entry for
3452 a given linear address.
3454 GDB can now pass command lines longer than 126 characters to the
3455 program being debugged (requires an update to the libdbg.a library
3456 which is part of the DJGPP development kit).
3458 DWARF2 debug info is now supported.
3460 It is now possible to `step' and `next' through calls to `longjmp'.
3462 * Changes in documentation.
3464 All GDB documentation was converted to GFDL, the GNU Free
3465 Documentation License.
3467 Tracepoints-related commands are now fully documented in the GDB
3470 TUI, the Text-mode User Interface, is now documented in the manual.
3472 Tracepoints-related commands are now fully documented in the GDB
3475 The "GDB Internals" manual now has an index. It also includes
3476 documentation of `ui_out' functions, GDB coding standards, x86
3477 hardware watchpoints, and memory region attributes.
3479 * GDB's version number moved to ``version.in''
3481 The Makefile variable VERSION has been replaced by the file
3482 ``version.in''. People creating GDB distributions should update the
3483 contents of this file.
3487 GUD support is now a standard part of the EMACS distribution.
3489 *** Changes in GDB 5.0:
3491 * Improved support for debugging FP programs on x86 targets
3493 Unified and much-improved support for debugging floating-point
3494 programs on all x86 targets. In particular, ``info float'' now
3495 displays the FP registers in the same format on all x86 targets, with
3496 greater level of detail.
3498 * Improvements and bugfixes in hardware-assisted watchpoints
3500 It is now possible to watch array elements, struct members, and
3501 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3502 on x86 targets no longer erroneously trigger when the address is
3505 * Improvements in the native DJGPP version of GDB
3507 The distribution now includes all the scripts and auxiliary files
3508 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3509 machines ``out of the box''.
3511 The DJGPP version can now debug programs that use signals. It is
3512 possible to catch signals that happened in the debuggee, deliver
3513 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3514 would kill the program being debugged.) Programs that hook hardware
3515 interrupts (keyboard, timer, etc.) can also be debugged.
3517 It is now possible to debug DJGPP programs that redirect their
3518 standard handles or switch them to raw (as opposed to cooked) mode, or
3519 even close them. The command ``run < foo > bar'' works as expected,
3520 and ``info terminal'' reports useful information about the debuggee's
3521 terminal, including raw/cooked mode, redirection, etc.
3523 The DJGPP version now uses termios functions for console I/O, which
3524 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3527 DOS-style file names with drive letters are now fully supported by
3530 It is now possible to debug DJGPP programs that switch their working
3531 directory. It is also possible to rerun the debuggee any number of
3532 times without restarting GDB; thus, you can use the same setup,
3533 breakpoints, etc. for many debugging sessions.
3535 * New native configurations
3537 ARM GNU/Linux arm*-*-linux*
3538 PowerPC GNU/Linux powerpc-*-linux*
3542 Motorola MCore mcore-*-*
3543 x86 VxWorks i[3456]86-*-vxworks*
3544 PowerPC VxWorks powerpc-*-vxworks*
3545 TI TMS320C80 tic80-*-*
3547 * OBSOLETE configurations
3549 Altos 3068 m68*-altos-*
3550 Convex c1-*-*, c2-*-*
3552 ARM RISCix arm-*-* (as host)
3555 Configurations that have been declared obsolete will be commented out,
3556 but the code will be left in place. If there is no activity to revive
3557 these configurations before the next release of GDB, the sources will
3558 be permanently REMOVED.
3560 * Gould support removed
3562 Support for the Gould PowerNode and NP1 has been removed.
3564 * New features for SVR4
3566 On SVR4 native platforms (such as Solaris), if you attach to a process
3567 without first loading a symbol file, GDB will now attempt to locate and
3568 load symbols from the running process's executable file.
3570 * Many C++ enhancements
3572 C++ support has been greatly improved. Overload resolution now works properly
3573 in almost all cases. RTTI support is on the way.
3575 * Remote targets can connect to a sub-program
3577 A popen(3) style serial-device has been added. This device starts a
3578 sub-process (such as a stand-alone simulator) and then communicates
3579 with that. The sub-program to run is specified using the syntax
3580 ``|<program> <args>'' vis:
3582 (gdb) set remotedebug 1
3583 (gdb) target extended-remote |mn10300-elf-sim program-args
3585 * MIPS 64 remote protocol
3587 A long standing bug in the mips64 remote protocol where by GDB
3588 expected certain 32 bit registers (ex SR) to be transfered as 32
3589 instead of 64 bits has been fixed.
3591 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3592 added to provide backward compatibility with older versions of GDB.
3594 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3596 The command ``set remotebinarydownload'' command has been replaced by
3597 ``set remote X-packet''. Other commands in ``set remote'' family
3598 include ``set remote P-packet''.
3600 * Breakpoint commands accept ranges.
3602 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3603 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3604 ``tracepoint passcount'' also accepts a range of tracepoints.
3606 * ``apropos'' command added.
3608 The ``apropos'' command searches through command names and
3609 documentation strings, printing out matches, making it much easier to
3610 try to find a command that does what you are looking for.
3614 A new machine oriented interface (MI) has been added to GDB. This
3615 interface is designed for debug environments running GDB as a separate
3616 process. This is part of the long term libGDB project. See the
3617 "GDB/MI" chapter of the GDB manual for further information. It can be
3618 enabled by configuring with:
3620 .../configure --enable-gdbmi
3622 *** Changes in GDB-4.18:
3624 * New native configurations
3626 HP-UX 10.20 hppa*-*-hpux10.20
3627 HP-UX 11.x hppa*-*-hpux11.0*
3628 M68K GNU/Linux m68*-*-linux*
3632 Fujitsu FR30 fr30-*-elf*
3633 Intel StrongARM strongarm-*-*
3634 Mitsubishi D30V d30v-*-*
3636 * OBSOLETE configurations
3638 Gould PowerNode, NP1 np1-*-*, pn-*-*
3640 Configurations that have been declared obsolete will be commented out,
3641 but the code will be left in place. If there is no activity to revive
3642 these configurations before the next release of GDB, the sources will
3643 be permanently REMOVED.
3647 As a compatibility experiment, GDB's source files buildsym.h and
3648 buildsym.c have been converted to pure standard C, no longer
3649 containing any K&R compatibility code. We believe that all systems in
3650 use today either come with a standard C compiler, or have a GCC port
3651 available. If this is not true, please report the affected
3652 configuration to bug-gdb@gnu.org immediately. See the README file for
3653 information about getting a standard C compiler if you don't have one
3658 GDB now uses readline 2.2.
3660 * set extension-language
3662 You can now control the mapping between filename extensions and source
3663 languages by using the `set extension-language' command. For instance,
3664 you can ask GDB to treat .c files as C++ by saying
3665 set extension-language .c c++
3666 The command `info extensions' lists all of the recognized extensions
3667 and their associated languages.
3669 * Setting processor type for PowerPC and RS/6000
3671 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3672 you can use the `set processor' command to specify what variant of the
3673 PowerPC family you are debugging. The command
3677 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3678 following PowerPC and RS6000 variants:
3680 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3681 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3683 403GC IBM PowerPC 403GC
3684 505 Motorola PowerPC 505
3685 860 Motorola PowerPC 860 or 850
3686 601 Motorola PowerPC 601
3687 602 Motorola PowerPC 602
3688 603 Motorola/IBM PowerPC 603 or 603e
3689 604 Motorola PowerPC 604 or 604e
3690 750 Motorola/IBM PowerPC 750 or 750
3692 At the moment, this command just tells GDB what to name the
3693 special-purpose processor registers. Since almost all the affected
3694 registers are inaccessible to user-level programs, this command is
3695 only useful for remote debugging in its present form.
3699 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3700 more extensive support for HP-UX. Added features include shared
3701 library support, kernel threads and hardware watchpoints for 11.00,
3702 support for HP's ANSI C and C++ compilers, and a compatibility mode
3703 for xdb and dbx commands.
3707 HP's donation includes the new concept of catchpoints, which is a
3708 generalization of the old catch command. On HP-UX, it is now possible
3709 to catch exec, fork, and vfork, as well as library loading.
3711 This means that the existing catch command has changed; its first
3712 argument now specifies the type of catch to be set up. See the
3713 output of "help catch" for a list of catchpoint types.
3715 * Debugging across forks
3717 On HP-UX, you can choose which process to debug when a fork() happens
3722 HP has donated a curses-based terminal user interface (TUI). To get
3723 it, build with --enable-tui. Although this can be enabled for any
3724 configuration, at present it only works for native HP debugging.
3726 * GDB remote protocol additions
3728 A new protocol packet 'X' that writes binary data is now available.
3729 Default behavior is to try 'X', then drop back to 'M' if the stub
3730 fails to respond. The settable variable `remotebinarydownload'
3731 allows explicit control over the use of 'X'.
3733 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3734 full 64-bit address. The command
3736 set remoteaddresssize 32
3738 can be used to revert to the old behaviour. For existing remote stubs
3739 the change should not be noticed, as the additional address information
3742 In order to assist in debugging stubs, you may use the maintenance
3743 command `packet' to send any text string to the stub. For instance,
3745 maint packet heythere
3747 sends the packet "$heythere#<checksum>". Note that it is very easy to
3748 disrupt a debugging session by sending the wrong packet at the wrong
3751 The compare-sections command allows you to compare section data on the
3752 target to what is in the executable file without uploading or
3753 downloading, by comparing CRC checksums.
3755 * Tracing can collect general expressions
3757 You may now collect general expressions at tracepoints. This requires
3758 further additions to the target-side stub; see tracepoint.c and
3759 doc/agentexpr.texi for further details.
3761 * mask-address variable for Mips
3763 For Mips targets, you may control the zeroing of the upper 32 bits of
3764 a 64-bit address by entering `set mask-address on'. This is mainly
3765 of interest to users of embedded R4xxx and R5xxx processors.
3767 * Higher serial baud rates
3769 GDB's serial code now allows you to specify baud rates 57600, 115200,
3770 230400, and 460800 baud. (Note that your host system may not be able
3771 to achieve all of these rates.)
3775 The i960 configuration now includes an initial implementation of a
3776 builtin simulator, contributed by Jim Wilson.
3779 *** Changes in GDB-4.17:
3781 * New native configurations
3783 Alpha GNU/Linux alpha*-*-linux*
3784 Unixware 2.x i[3456]86-unixware2*
3785 Irix 6.x mips*-sgi-irix6*
3786 PowerPC GNU/Linux powerpc-*-linux*
3787 PowerPC Solaris powerpcle-*-solaris*
3788 Sparc GNU/Linux sparc-*-linux*
3789 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3793 Argonaut Risc Chip (ARC) arc-*-*
3794 Hitachi H8/300S h8300*-*-*
3795 Matsushita MN10200 w/simulator mn10200-*-*
3796 Matsushita MN10300 w/simulator mn10300-*-*
3797 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3798 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3799 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3800 Mitsubishi D10V w/simulator d10v-*-*
3801 Mitsubishi M32R/D w/simulator m32r-*-elf*
3802 Tsqware Sparclet sparclet-*-*
3803 NEC V850 w/simulator v850-*-*
3805 * New debugging protocols
3807 ARM with RDI protocol arm*-*-*
3808 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3809 DDB and LSI variants of PMON protocol mips*-*-*
3810 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3811 PowerPC with SDS protocol powerpc{,le}-*-eabi
3812 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3816 All configurations can now understand and use the DWARF 2 debugging
3817 format. The choice is automatic, if the symbol file contains DWARF 2
3822 GDB now includes basic Java language support. This support is
3823 only useful with Java compilers that produce native machine code.
3825 * solib-absolute-prefix and solib-search-path
3827 For SunOS and SVR4 shared libraries, you may now set the prefix for
3828 loading absolute shared library symbol files, and the search path for
3829 locating non-absolute shared library symbol files.
3831 * Live range splitting
3833 GDB can now effectively debug code for which GCC has performed live
3834 range splitting as part of its optimization. See gdb/doc/LRS for
3835 more details on the expected format of the stabs information.
3839 GDB's support for the GNU Hurd, including thread debugging, has been
3840 updated to work with current versions of the Hurd.
3844 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3845 instruction set. ARM GDB automatically detects when Thumb
3846 instructions are in use, and adjusts disassembly and backtracing
3851 GDB's MIPS target configurations now handle the MIP16 16-bit
3856 GDB now includes support for overlays; if an executable has been
3857 linked such that multiple sections are based at the same address, GDB
3858 will decide which section to use for symbolic info. You can choose to
3859 control the decision manually, using overlay commands, or implement
3860 additional target-side support and use "overlay load-target" to bring
3861 in the overlay mapping. Do "help overlay" for more detail.
3865 The command "info symbol <address>" displays information about
3866 the symbol at the specified address.
3870 The standard remote protocol now includes an extension that allows
3871 asynchronous collection and display of trace data. This requires
3872 extensive support in the target-side debugging stub. Tracing mode
3873 includes a new interaction mode in GDB and new commands: see the
3874 file tracepoint.c for more details.
3878 Configurations for embedded MIPS now include a simulator contributed
3879 by Cygnus Solutions. The simulator supports the instruction sets
3880 of most MIPS variants.
3884 Sparc configurations may now include the ERC32 simulator contributed
3885 by the European Space Agency. The simulator is not built into
3886 Sparc targets by default; configure with --enable-sim to include it.
3890 For target configurations that may include multiple variants of a
3891 basic architecture (such as MIPS and SH), you may now set the
3892 architecture explicitly. "set arch" sets, "info arch" lists
3893 the possible architectures.
3895 *** Changes in GDB-4.16:
3897 * New native configurations
3899 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3900 M68K NetBSD m68k-*-netbsd*
3901 PowerPC AIX 4.x powerpc-*-aix*
3902 PowerPC MacOS powerpc-*-macos*
3903 PowerPC Windows NT powerpcle-*-cygwin32
3904 RS/6000 AIX 4.x rs6000-*-aix4*
3908 ARM with RDP protocol arm-*-*
3909 I960 with MON960 i960-*-coff
3910 MIPS VxWorks mips*-*-vxworks*
3911 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3912 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3914 Matra Sparclet sparclet-*-*
3918 The powerpc-eabi configuration now includes the PSIM simulator,
3919 contributed by Andrew Cagney, with assistance from Mike Meissner.
3920 PSIM is a very elaborate model of the PowerPC, including not only
3921 basic instruction set execution, but also details of execution unit
3922 performance and I/O hardware. See sim/ppc/README for more details.
3926 GDB now works with Solaris 2.5.
3928 * Windows 95/NT native
3930 GDB will now work as a native debugger on Windows 95 and Windows NT.
3931 To build it from source, you must use the "gnu-win32" environment,
3932 which uses a DLL to emulate enough of Unix to run the GNU tools.
3933 Further information, binaries, and sources are available at
3934 ftp.cygnus.com, under pub/gnu-win32.
3936 * dont-repeat command
3938 If a user-defined command includes the command `dont-repeat', then the
3939 command will not be repeated if the user just types return. This is
3940 useful if the command is time-consuming to run, so that accidental
3941 extra keystrokes don't run the same command many times.
3943 * Send break instead of ^C
3945 The standard remote protocol now includes an option to send a break
3946 rather than a ^C to the target in order to interrupt it. By default,
3947 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3949 * Remote protocol timeout
3951 The standard remote protocol includes a new variable `remotetimeout'
3952 that allows you to set the number of seconds before GDB gives up trying
3953 to read from the target. The default value is 2.
3955 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3957 By default GDB will automatically keep track of objects as they are
3958 loaded and unloaded by the dynamic linker. By using the command `set
3959 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3960 when shared library events occur, thus allowing you to set breakpoints
3961 in shared libraries which are explicitly loaded by the inferior.
3963 Note this feature does not work on hpux8. On hpux9 you must link
3964 /usr/lib/end.o into your program. This feature should work
3965 automatically on hpux10.
3967 * Irix 5.x hardware watchpoint support
3969 Irix 5 configurations now support the use of hardware watchpoints.
3971 * Mips protocol "SYN garbage limit"
3973 When debugging a Mips target using the `target mips' protocol, you
3974 may set the number of characters that GDB will ignore by setting
3975 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3976 every character. The default value is 1050.
3978 * Recording and replaying remote debug sessions
3980 If you set `remotelogfile' to the name of a file, gdb will write to it
3981 a recording of a remote debug session. This recording may then be
3982 replayed back to gdb using "gdbreplay". See gdbserver/README for
3983 details. This is useful when you have a problem with GDB while doing
3984 remote debugging; you can make a recording of the session and send it
3985 to someone else, who can then recreate the problem.
3987 * Speedups for remote debugging
3989 GDB includes speedups for downloading and stepping MIPS systems using
3990 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3991 and more efficient S-record downloading.
3993 * Memory use reductions and statistics collection
3995 GDB now uses less memory and reports statistics about memory usage.
3996 Try the `maint print statistics' command, for example.
3998 *** Changes in GDB-4.15:
4000 * Psymtabs for XCOFF
4002 The symbol reader for AIX GDB now uses partial symbol tables. This
4003 can greatly improve startup time, especially for large executables.
4005 * Remote targets use caching
4007 Remote targets now use a data cache to speed up communication with the
4008 remote side. The data cache could lead to incorrect results because
4009 it doesn't know about volatile variables, thus making it impossible to
4010 debug targets which use memory mapped I/O devices. `set remotecache
4011 off' turns the the data cache off.
4013 * Remote targets may have threads
4015 The standard remote protocol now includes support for multiple threads
4016 in the target system, using new protocol commands 'H' and 'T'. See
4017 gdb/remote.c for details.
4021 If GDB is configured with `--enable-netrom', then it will include
4022 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4023 acts as though it is a bank of ROM on the target board, but you can
4024 write into it over the network. GDB's support consists only of
4025 support for fast loading into the emulated ROM; to debug, you must use
4026 another protocol, such as standard remote protocol. The usual
4027 sequence is something like
4029 target nrom <netrom-hostname>
4031 target remote <netrom-hostname>:1235
4035 GDB now includes support for the Apple Macintosh, as a host only. It
4036 may be run as either an MPW tool or as a standalone application, and
4037 it can debug through the serial port. All the usual GDB commands are
4038 available, but to the target command, you must supply "serial" as the
4039 device type instead of "/dev/ttyXX". See mpw-README in the main
4040 directory for more information on how to build. The MPW configuration
4041 scripts */mpw-config.in support only a few targets, and only the
4042 mips-idt-ecoff target has been tested.
4046 GDB configuration now uses autoconf. This is not user-visible,
4047 but does simplify configuration and building.
4051 GDB now supports hpux10.
4053 *** Changes in GDB-4.14:
4055 * New native configurations
4057 x86 FreeBSD i[345]86-*-freebsd
4058 x86 NetBSD i[345]86-*-netbsd
4059 NS32k NetBSD ns32k-*-netbsd
4060 Sparc NetBSD sparc-*-netbsd
4064 A29K VxWorks a29k-*-vxworks
4065 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4066 CPU32 EST-300 emulator m68*-*-est*
4067 PowerPC ELF powerpc-*-elf
4070 * Alpha OSF/1 support for procfs
4072 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4073 possible to attach to running processes. As the mounting of the /proc
4074 filesystem is optional on the Alpha, GDB automatically determines
4075 the availability of /proc during startup. This can lead to problems
4076 if /proc is unmounted after GDB has been started.
4078 * Arguments to user-defined commands
4080 User commands may accept up to 10 arguments separated by whitespace.
4081 Arguments are accessed within the user command via $arg0..$arg9. A
4084 print $arg0 + $arg1 + $arg2
4086 To execute the command use:
4089 Defines the command "adder" which prints the sum of its three arguments.
4090 Note the arguments are text substitutions, so they may reference variables,
4091 use complex expressions, or even perform inferior function calls.
4093 * New `if' and `while' commands
4095 This makes it possible to write more sophisticated user-defined
4096 commands. Both commands take a single argument, which is the
4097 expression to evaluate, and must be followed by the commands to
4098 execute, one per line, if the expression is nonzero, the list being
4099 terminated by the word `end'. The `if' command list may include an
4100 `else' word, which causes the following commands to be executed only
4101 if the expression is zero.
4103 * Fortran source language mode
4105 GDB now includes partial support for Fortran 77. It will recognize
4106 Fortran programs and can evaluate a subset of Fortran expressions, but
4107 variables and functions may not be handled correctly. GDB will work
4108 with G77, but does not yet know much about symbols emitted by other
4111 * Better HPUX support
4113 Most debugging facilities now work on dynamic executables for HPPAs
4114 running hpux9 or later. You can attach to running dynamically linked
4115 processes, but by default the dynamic libraries will be read-only, so
4116 for instance you won't be able to put breakpoints in them. To change
4117 that behavior do the following before running the program:
4123 This will cause the libraries to be mapped private and read-write.
4124 To revert to the normal behavior, do this:
4130 You cannot set breakpoints or examine data in the library until after
4131 the library is loaded if the function/data symbols do not have
4134 GDB can now also read debug symbols produced by the HP C compiler on
4135 HPPAs (sorry, no C++, Fortran or 68k support).
4137 * Target byte order now dynamically selectable
4139 You can choose which byte order to use with a target system, via the
4140 commands "set endian big" and "set endian little", and you can see the
4141 current setting by using "show endian". You can also give the command
4142 "set endian auto", in which case GDB will use the byte order
4143 associated with the executable. Currently, only embedded MIPS
4144 configurations support dynamic selection of target byte order.
4146 * New DOS host serial code
4148 This version uses DPMI interrupts to handle buffered I/O, so you
4149 no longer need to run asynctsr when debugging boards connected to
4152 *** Changes in GDB-4.13:
4154 * New "complete" command
4156 This lists all the possible completions for the rest of the line, if it
4157 were to be given as a command itself. This is intended for use by emacs.
4159 * Trailing space optional in prompt
4161 "set prompt" no longer adds a space for you after the prompt you set. This
4162 allows you to set a prompt which ends in a space or one that does not.
4164 * Breakpoint hit counts
4166 "info break" now displays a count of the number of times the breakpoint
4167 has been hit. This is especially useful in conjunction with "ignore"; you
4168 can ignore a large number of breakpoint hits, look at the breakpoint info
4169 to see how many times the breakpoint was hit, then run again, ignoring one
4170 less than that number, and this will get you quickly to the last hit of
4173 * Ability to stop printing at NULL character
4175 "set print null-stop" will cause GDB to stop printing the characters of
4176 an array when the first NULL is encountered. This is useful when large
4177 arrays actually contain only short strings.
4179 * Shared library breakpoints
4181 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4182 breakpoints in shared libraries before the executable is run.
4184 * Hardware watchpoints
4186 There is a new hardware breakpoint for the watch command for sparclite
4187 targets. See gdb/sparclite/hw_breakpoint.note.
4189 Hardware watchpoints are also now supported under GNU/Linux.
4193 Annotations have been added. These are for use with graphical interfaces,
4194 and are still experimental. Currently only gdba.el uses these.
4196 * Improved Irix 5 support
4198 GDB now works properly with Irix 5.2.
4200 * Improved HPPA support
4202 GDB now works properly with the latest GCC and GAS.
4204 * New native configurations
4206 Sequent PTX4 i[34]86-sequent-ptx4
4207 HPPA running OSF/1 hppa*-*-osf*
4208 Atari TT running SVR4 m68*-*-sysv4*
4209 RS/6000 LynxOS rs6000-*-lynxos*
4213 OS/9000 i[34]86-*-os9k
4214 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4217 * Hitachi SH7000 and E7000-PC ICE support
4219 There is now support for communicating with the Hitachi E7000-PC ICE.
4220 This is available automatically when GDB is configured for the SH.
4224 As usual, a variety of small fixes and improvements, both generic
4225 and configuration-specific. See the ChangeLog for more detail.
4227 *** Changes in GDB-4.12:
4229 * Irix 5 is now supported
4233 GDB-4.12 on the HPPA has a number of changes which make it unable
4234 to debug the output from the currently released versions of GCC and
4235 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4236 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4237 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4240 *** Changes in GDB-4.11:
4242 * User visible changes:
4246 The "set remotedebug" option is now consistent between the mips remote
4247 target, remote targets using the gdb-specific protocol, UDI (AMD's
4248 debug protocol for the 29k) and the 88k bug monitor. It is now an
4249 integer specifying a debug level (normally 0 or 1, but 2 means more
4250 debugging info for the mips target).
4252 * DEC Alpha native support
4254 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4255 debug info, but GDB works fairly well with the DEC compiler and should
4256 work with a future GCC release. See the README file for a few
4257 Alpha-specific notes.
4259 * Preliminary thread implementation
4261 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4263 * LynxOS native and target support for 386
4265 This release has been hosted on LynxOS 2.2, and also can be configured
4266 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4269 * Improvements in C++ mangling/demangling.
4271 This release has much better g++ debugging, specifically in name
4272 mangling/demangling, virtual function calls, print virtual table,
4273 call methods, ...etc.
4275 *** Changes in GDB-4.10:
4277 * User visible changes:
4279 Remote debugging using the GDB-specific (`target remote') protocol now
4280 supports the `load' command. This is only useful if you have some
4281 other way of getting the stub to the target system, and you can put it
4282 somewhere in memory where it won't get clobbered by the download.
4284 Filename completion now works.
4286 When run under emacs mode, the "info line" command now causes the
4287 arrow to point to the line specified. Also, "info line" prints
4288 addresses in symbolic form (as well as hex).
4290 All vxworks based targets now support a user settable option, called
4291 vxworks-timeout. This option represents the number of seconds gdb
4292 should wait for responses to rpc's. You might want to use this if
4293 your vxworks target is, perhaps, a slow software simulator or happens
4294 to be on the far side of a thin network line.
4298 This release contains support for using a DEC alpha as a GDB host for
4299 cross debugging. Native alpha debugging is not supported yet.
4302 *** Changes in GDB-4.9:
4306 This is the first GDB release which is accompanied by a matching testsuite.
4307 The testsuite requires installation of dejagnu, which should be available
4308 via ftp from most sites that carry GNU software.
4312 'Cfront' style demangling has had its name changed to 'ARM' style, to
4313 emphasize that it was written from the specifications in the C++ Annotated
4314 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4315 disclaimers, it still generated too much confusion with users attempting to
4316 use gdb with AT&T cfront.
4320 GDB now uses a standard remote interface to a simulator library.
4321 So far, the library contains simulators for the Zilog Z8001/2, the
4322 Hitachi H8/300, H8/500 and Super-H.
4324 * New targets supported
4326 H8/300 simulator h8300-hitachi-hms or h8300hms
4327 H8/500 simulator h8500-hitachi-hms or h8500hms
4328 SH simulator sh-hitachi-hms or sh
4329 Z8000 simulator z8k-zilog-none or z8ksim
4330 IDT MIPS board over serial line mips-idt-ecoff
4332 Cross-debugging to GO32 targets is supported. It requires a custom
4333 version of the i386-stub.c module which is integrated with the
4334 GO32 memory extender.
4336 * New remote protocols
4338 MIPS remote debugging protocol.
4340 * New source languages supported
4342 This version includes preliminary support for Chill, a Pascal like language
4343 used by telecommunications companies. Chill support is also being integrated
4344 into the GNU compiler, but we don't know when it will be publically available.
4347 *** Changes in GDB-4.8:
4349 * HP Precision Architecture supported
4351 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4352 version of this support was available as a set of patches from the
4353 University of Utah. GDB does not support debugging of programs
4354 compiled with the HP compiler, because HP will not document their file
4355 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4356 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4358 Many problems in the preliminary version have been fixed.
4360 * Faster and better demangling
4362 We have improved template demangling and fixed numerous bugs in the GNU style
4363 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4364 character types (wchar_t) are now supported. Demangling of each symbol is now
4365 only done once, and is cached when the symbol table for a file is read in.
4366 This results in a small increase in memory usage for C programs, a moderate
4367 increase in memory usage for C++ programs, and a fantastic speedup in
4370 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4371 from the specifications in the Annotated Reference Manual, which AT&T's
4372 compiler does not actually implement.
4374 * G++ multiple inheritance compiler problem
4376 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4377 inheritance lattices was reworked to properly discover ambiguities. We
4378 recently found an example which causes this new algorithm to fail in a
4379 very subtle way, producing bad debug information for those classes.
4380 The file 'gcc.patch' (in this directory) can be applied to gcc to
4381 circumvent the problem. A future GCC release will contain a complete
4384 The previous G++ debug info problem (mentioned below for the gdb-4.7
4385 release) is fixed in gcc version 2.3.2.
4387 * Improved configure script
4389 The `configure' script will now attempt to guess your system type if
4390 you don't supply a host system type. The old scheme of supplying a
4391 host system triplet is preferable over using this. All the magic is
4392 done in the new `config.guess' script. Examine it for details.
4394 We have also brought our configure script much more in line with the FSF's
4395 version. It now supports the --with-xxx options. In particular,
4396 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4397 The resulting GDB will not be able to read arbitrary object file formats --
4398 only the format ``expected'' to be used on the configured target system.
4399 We hope to make this the default in a future release.
4401 * Documentation improvements
4403 There's new internal documentation on how to modify GDB, and how to
4404 produce clean changes to the code. We implore people to read it
4405 before submitting changes.
4407 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4408 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4409 `info' files are also provided. To build `info' files from scratch,
4410 you will need the latest `makeinfo' release, which will be available in
4411 a future texinfo-X.Y release.
4413 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4414 We're not sure exactly which versions have this problem, but it has
4415 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4416 or better. If that isn't possible, there is a patch in
4417 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4418 around this problem.
4422 GDB now supports array constants that can be used in expressions typed in by
4423 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4424 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4427 The new directory `gdb/sparclite' contains a program that demonstrates
4428 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4430 * New native hosts supported
4432 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4433 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4435 * New targets supported
4437 AMD 29k family via UDI a29k-amd-udi or udi29k
4439 * New file formats supported
4441 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4442 HPUX core files, and SCO 3.2v2 core files.
4446 Attaching to processes now works again; thanks for the many bug reports.
4448 We have also stomped on a bunch of core dumps caused by
4449 printf_filtered("%s") problems.
4451 We eliminated a copyright problem on the rpc and ptrace header files
4452 for VxWorks, which was discovered at the last minute during the 4.7
4453 release. You should now be able to build a VxWorks GDB.
4455 You can now interrupt gdb while an attached process is running. This
4456 will cause the attached process to stop, and give control back to GDB.
4458 We fixed problems caused by using too many file descriptors
4459 for reading symbols from object files and libraries. This was
4460 especially a problem for programs that used many (~100) shared
4463 The `step' command now only enters a subroutine if there is line number
4464 information for the subroutine. Otherwise it acts like the `next'
4465 command. Previously, `step' would enter subroutines if there was
4466 any debugging information about the routine. This avoids problems
4467 when using `cc -g1' on MIPS machines.
4469 * Internal improvements
4471 GDB's internal interfaces have been improved to make it easier to support
4472 debugging of multiple languages in the future.
4474 GDB now uses a common structure for symbol information internally.
4475 Minimal symbols (derived from linkage symbols in object files), partial
4476 symbols (from a quick scan of debug information), and full symbols
4477 contain a common subset of information, making it easier to write
4478 shared code that handles any of them.
4480 * New command line options
4482 We now accept --silent as an alias for --quiet.
4486 The memory-mapped-malloc library is now licensed under the GNU Library
4487 General Public License.
4489 *** Changes in GDB-4.7:
4491 * Host/native/target split
4493 GDB has had some major internal surgery to untangle the support for
4494 hosts and remote targets. Now, when you configure GDB for a remote
4495 target, it will no longer load in all of the support for debugging
4496 local programs on the host. When fully completed and tested, this will
4497 ensure that arbitrary host/target combinations are possible.
4499 The primary conceptual shift is to separate the non-portable code in
4500 GDB into three categories. Host specific code is required any time GDB
4501 is compiled on that host, regardless of the target. Target specific
4502 code relates to the peculiarities of the target, but can be compiled on
4503 any host. Native specific code is everything else: it can only be
4504 built when the host and target are the same system. Child process
4505 handling and core file support are two common `native' examples.
4507 GDB's use of /proc for controlling Unix child processes is now cleaner.
4508 It has been split out into a single module under the `target_ops' vector,
4509 plus two native-dependent functions for each system that uses /proc.
4511 * New hosts supported
4513 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4514 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4515 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4517 * New targets supported
4519 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4520 68030 and CPU32 m68030-*-*, m68332-*-*
4522 * New native hosts supported
4524 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4525 (386bsd is not well tested yet)
4526 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4528 * New file formats supported
4530 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4531 supports reading of `a.out.adobe' object files, which are an a.out
4532 format extended with minimal information about multiple sections.
4536 `show copying' is the same as the old `info copying'.
4537 `show warranty' is the same as `info warrantee'.
4538 These were renamed for consistency. The old commands continue to work.
4540 `info handle' is a new alias for `info signals'.
4542 You can now define pre-command hooks, which attach arbitrary command
4543 scripts to any command. The commands in the hook will be executed
4544 prior to the user's command. You can also create a hook which will be
4545 executed whenever the program stops. See gdb.texinfo.
4549 We now deal with Cfront style name mangling, and can even extract type
4550 info from mangled symbols. GDB can automatically figure out which
4551 symbol mangling style your C++ compiler uses.
4553 Calling of methods and virtual functions has been improved as well.
4557 The crash that occured when debugging Sun Ansi-C compiled binaries is
4558 fixed. This was due to mishandling of the extra N_SO stabs output
4561 We also finally got Ultrix 4.2 running in house, and fixed core file
4562 support, with help from a dozen people on the net.
4564 John M. Farrell discovered that the reason that single-stepping was so
4565 slow on all of the Mips based platforms (primarily SGI and DEC) was
4566 that we were trying to demangle and lookup a symbol used for internal
4567 purposes on every instruction that was being stepped through. Changing
4568 the name of that symbol so that it couldn't be mistaken for a C++
4569 mangled symbol sped things up a great deal.
4571 Rich Pixley sped up symbol lookups in general by getting much smarter
4572 about when C++ symbol mangling is necessary. This should make symbol
4573 completion (TAB on the command line) much faster. It's not as fast as
4574 we'd like, but it's significantly faster than gdb-4.6.
4578 A new user controllable variable 'call_scratch_address' can
4579 specify the location of a scratch area to be used when GDB
4580 calls a function in the target. This is necessary because the
4581 usual method of putting the scratch area on the stack does not work
4582 in systems that have separate instruction and data spaces.
4584 We integrated changes to support the 29k UDI (Universal Debugger
4585 Interface), but discovered at the last minute that we didn't have all
4586 of the appropriate copyright paperwork. We are working with AMD to
4587 resolve this, and hope to have it available soon.
4591 We have sped up the remote serial line protocol, especially for targets
4592 with lots of registers. It now supports a new `expedited status' ('T')
4593 message which can be used in place of the existing 'S' status message.
4594 This allows the remote stub to send only the registers that GDB
4595 needs to make a quick decision about single-stepping or conditional
4596 breakpoints, eliminating the need to fetch the entire register set for
4597 each instruction being stepped through.
4599 The GDB remote serial protocol now implements a write-through cache for
4600 registers, only re-reading the registers if the target has run.
4602 There is also a new remote serial stub for SPARC processors. You can
4603 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4604 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4605 processor with a serial port.
4609 Configure.in files have become much easier to read and modify. A new
4610 `table driven' format makes it more obvious what configurations are
4611 supported, and what files each one uses.
4615 There is a new opcodes library which will eventually contain all of the
4616 disassembly routines and opcode tables. At present, it only contains
4617 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4618 disassembler (binutils/objdump) to share these routines.
4620 The libiberty library is now copylefted under the GNU Library General
4621 Public License. This allows more liberal use, and was done so libg++
4622 can use it. This makes no difference to GDB, since the Library License
4623 grants all the rights from the General Public License.
4627 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4628 reference to the stabs symbol info used by the debugger. It is (as far
4629 as we know) the only published document on this fascinating topic. We
4630 encourage you to read it, compare it to the stabs information on your
4631 system, and send improvements on the document in general (to
4632 bug-gdb@prep.ai.mit.edu).
4634 And, of course, many bugs have been fixed.
4637 *** Changes in GDB-4.6:
4639 * Better support for C++ function names
4641 GDB now accepts as input the "demangled form" of C++ overloaded function
4642 names and member function names, and can do command completion on such names
4643 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4644 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4645 Make use of command completion, it is your friend.
4647 GDB also now accepts a variety of C++ mangled symbol formats. They are
4648 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4649 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4650 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4651 for the list of formats.
4653 * G++ symbol mangling problem
4655 Recent versions of gcc have a bug in how they emit debugging information for
4656 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4657 directory) can be applied to gcc to fix the problem. Alternatively, if you
4658 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4659 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4660 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4663 * New 'maintenance' command
4665 All of the commands related to hacking GDB internals have been moved out of
4666 the main command set, and now live behind the 'maintenance' command. This
4667 can also be abbreviated as 'mt'. The following changes were made:
4669 dump-me -> maintenance dump-me
4670 info all-breakpoints -> maintenance info breakpoints
4671 printmsyms -> maintenance print msyms
4672 printobjfiles -> maintenance print objfiles
4673 printpsyms -> maintenance print psymbols
4674 printsyms -> maintenance print symbols
4676 The following commands are new:
4678 maintenance demangle Call internal GDB demangler routine to
4679 demangle a C++ link name and prints the result.
4680 maintenance print type Print a type chain for a given symbol
4682 * Change to .gdbinit file processing
4684 We now read the $HOME/.gdbinit file before processing the argv arguments
4685 (e.g. reading symbol files or core files). This allows global parameters to
4686 be set, which will apply during the symbol reading. The ./.gdbinit is still
4687 read after argv processing.
4689 * New hosts supported
4691 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4693 GNU/Linux support i386-unknown-linux or linux
4695 We are also including code to support the HP/PA running BSD and HPUX. This
4696 is almost guaranteed not to work, as we didn't have time to test or build it
4697 for this release. We are including it so that the more adventurous (or
4698 masochistic) of you can play with it. We also had major problems with the
4699 fact that the compiler that we got from HP doesn't support the -g option.
4702 * New targets supported
4704 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4706 * More smarts about finding #include files
4708 GDB now remembers the compilation directory for all include files, and for
4709 all files from which C is generated (like yacc and lex sources). This
4710 greatly improves GDB's ability to find yacc/lex sources, and include files,
4711 especially if you are debugging your program from a directory different from
4712 the one that contains your sources.
4714 We also fixed a bug which caused difficulty with listing and setting
4715 breakpoints in include files which contain C code. (In the past, you had to
4716 try twice in order to list an include file that you hadn't looked at before.)
4718 * Interesting infernals change
4720 GDB now deals with arbitrary numbers of sections, where the symbols for each
4721 section must be relocated relative to that section's landing place in the
4722 target's address space. This work was needed to support ELF with embedded
4723 stabs used by Solaris-2.0.
4725 * Bug fixes (of course!)
4727 There have been loads of fixes for the following things:
4728 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4729 i960, stabs, DOS(GO32), procfs, etc...
4731 See the ChangeLog for details.
4733 *** Changes in GDB-4.5:
4735 * New machines supported (host and target)
4737 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4739 SGI Irix-4.x mips-sgi-irix4 or iris4
4741 * New malloc package
4743 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4744 Mmalloc is capable of handling mutiple heaps of memory. It is also
4745 capable of saving a heap to a file, and then mapping it back in later.
4746 This can be used to greatly speedup the startup of GDB by using a
4747 pre-parsed symbol table which lives in a mmalloc managed heap. For
4748 more details, please read mmalloc/mmalloc.texi.
4752 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4753 'help info proc' for details.
4755 * MIPS ecoff symbol table format
4757 The code that reads MIPS symbol table format is now supported on all hosts.
4758 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4761 * File name changes for MS-DOS
4763 Many files in the config directories have been renamed to make it easier to
4764 support GDB on MS-DOSe systems (which have very restrictive file name
4765 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4766 environment) is close to working but has some remaining problems. Note
4767 that debugging of DOS programs is not supported, due to limitations
4768 in the ``operating system'', but it can be used to host cross-debugging.
4770 * Cross byte order fixes
4772 Many fixes have been made to support cross debugging of Sparc and MIPS
4773 targets from hosts whose byte order differs.
4775 * New -mapped and -readnow options
4777 If memory-mapped files are available on your system through the 'mmap'
4778 system call, you can use the -mapped option on the `file' or
4779 `symbol-file' commands to cause GDB to write the symbols from your
4780 program into a reusable file. If the program you are debugging is
4781 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4782 Future GDB debugging sessions will notice the presence of this file,
4783 and will quickly map in symbol information from it, rather than reading
4784 the symbol table from the executable program. Using the '-mapped'
4785 option in a GDB `file' or `symbol-file' command has the same effect as
4786 starting GDB with the '-mapped' command-line option.
4788 You can cause GDB to read the entire symbol table immediately by using
4789 the '-readnow' option with any of the commands that load symbol table
4790 information (or on the GDB command line). This makes the command
4791 slower, but makes future operations faster.
4793 The -mapped and -readnow options are typically combined in order to
4794 build a `fred.syms' file that contains complete symbol information.
4795 A simple GDB invocation to do nothing but build a `.syms' file for future
4798 gdb -batch -nx -mapped -readnow programname
4800 The `.syms' file is specific to the host machine on which GDB is run.
4801 It holds an exact image of GDB's internal symbol table. It cannot be
4802 shared across multiple host platforms.
4804 * longjmp() handling
4806 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4807 siglongjmp() without losing control. This feature has not yet been ported to
4808 all systems. It currently works on many 386 platforms, all MIPS-based
4809 platforms (SGI, DECstation, etc), and Sun3/4.
4813 Preliminary work has been put in to support the new Solaris OS from Sun. At
4814 this time, it can control and debug processes, but it is not capable of
4819 As always, many many bug fixes. The major areas were with g++, and mipsread.
4820 People using the MIPS-based platforms should experience fewer mysterious
4821 crashes and trashed symbol tables.
4823 *** Changes in GDB-4.4:
4825 * New machines supported (host and target)
4827 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4829 BSD Reno on Vax vax-dec-bsd
4830 Ultrix on Vax vax-dec-ultrix
4832 * New machines supported (target)
4834 AMD 29000 embedded, using EBMON a29k-none-none
4838 GDB continues to improve its handling of C++. `References' work better.
4839 The demangler has also been improved, and now deals with symbols mangled as
4840 per the Annotated C++ Reference Guide.
4842 GDB also now handles `stabs' symbol information embedded in MIPS
4843 `ecoff' symbol tables. Since the ecoff format was not easily
4844 extensible to handle new languages such as C++, this appeared to be a
4845 good way to put C++ debugging info into MIPS binaries. This option
4846 will be supported in the GNU C compiler, version 2, when it is
4849 * New features for SVR4
4851 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4852 shared libraries. Debugging dynamically linked programs should present
4853 only minor differences from debugging statically linked programs.
4855 The `info proc' command will print out information about any process
4856 on an SVR4 system (including the one you are debugging). At the moment,
4857 it prints the address mappings of the process.
4859 If you bring up GDB on another SVR4 system, please send mail to
4860 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4862 * Better dynamic linking support in SunOS
4864 Reading symbols from shared libraries which contain debugging symbols
4865 now works properly. However, there remain issues such as automatic
4866 skipping of `transfer vector' code during function calls, which
4867 make it harder to debug code in a shared library, than to debug the
4868 same code linked statically.
4872 GDB is now using the latest `getopt' routines from the FSF. This
4873 version accepts the -- prefix for options with long names. GDB will
4874 continue to accept the old forms (-option and +option) as well.
4875 Various single letter abbreviations for options have been explicity
4876 added to the option table so that they won't get overshadowed in the
4877 future by other options that begin with the same letter.
4881 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4882 Many assorted bugs have been handled. Many more remain to be handled.
4883 See the various ChangeLog files (primarily in gdb and bfd) for details.
4886 *** Changes in GDB-4.3:
4888 * New machines supported (host and target)
4890 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4891 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4892 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4894 * Almost SCO Unix support
4896 We had hoped to support:
4897 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4898 (except for core file support), but we discovered very late in the release
4899 that it has problems with process groups that render gdb unusable. Sorry
4900 about that. I encourage people to fix it and post the fixes.
4902 * Preliminary ELF and DWARF support
4904 GDB can read ELF object files on System V Release 4, and can handle
4905 debugging records for C, in DWARF format, in ELF files. This support
4906 is preliminary. If you bring up GDB on another SVR4 system, please
4907 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4912 GDB now uses the latest `readline' library. One user-visible change
4913 is that two tabs will list possible command completions, which previously
4914 required typing M-? (meta-question mark, or ESC ?).
4918 The `stepi' bug that many of you noticed has been squashed.
4919 Many bugs in C++ have been handled. Many more remain to be handled.
4920 See the various ChangeLog files (primarily in gdb and bfd) for details.
4922 * State of the MIPS world (in case you wondered):
4924 GDB can understand the symbol tables emitted by the compilers
4925 supplied by most vendors of MIPS-based machines, including DEC. These
4926 symbol tables are in a format that essentially nobody else uses.
4928 Some versions of gcc come with an assembler post-processor called
4929 mips-tfile. This program is required if you want to do source-level
4930 debugging of gcc-compiled programs. I believe FSF does not ship
4931 mips-tfile with gcc version 1, but it will eventually come with gcc
4934 Debugging of g++ output remains a problem. g++ version 1.xx does not
4935 really support it at all. (If you're lucky, you should be able to get
4936 line numbers and stack traces to work, but no parameters or local
4937 variables.) With some work it should be possible to improve the
4940 When gcc version 2 is released, you will have somewhat better luck.
4941 However, even then you will get confusing results for inheritance and
4944 We will eventually provide full debugging of g++ output on
4945 DECstations. This will probably involve some kind of stabs-in-ecoff
4946 encapulation, but the details have not been worked out yet.
4949 *** Changes in GDB-4.2:
4951 * Improved configuration
4953 Only one copy of `configure' exists now, and it is not self-modifying.
4954 Porting BFD is simpler.
4958 The `step' and `next' commands now only stop at the first instruction
4959 of a source line. This prevents the multiple stops that used to occur
4960 in switch statements, for-loops, etc. `Step' continues to stop if a
4961 function that has debugging information is called within the line.
4965 Lots of small bugs fixed. More remain.
4967 * New host supported (not target)
4969 Intel 386 PC clone running Mach i386-none-mach
4972 *** Changes in GDB-4.1:
4974 * Multiple source language support
4976 GDB now has internal scaffolding to handle several source languages.
4977 It determines the type of each source file from its filename extension,
4978 and will switch expression parsing and number formatting to match the
4979 language of the function in the currently selected stack frame.
4980 You can also specifically set the language to be used, with
4981 `set language c' or `set language modula-2'.
4985 GDB now has preliminary support for the GNU Modula-2 compiler,
4986 currently under development at the State University of New York at
4987 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4988 continue through the fall of 1991 and into 1992.
4990 Other Modula-2 compilers are currently not supported, and attempting to
4991 debug programs compiled with them will likely result in an error as the
4992 symbol table is read. Feel free to work on it, though!
4994 There are hooks in GDB for strict type checking and range checking,
4995 in the `Modula-2 philosophy', but they do not currently work.
4999 GDB can now write to executable and core files (e.g. patch
5000 a variable's value). You must turn this switch on, specify
5001 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5002 by assigning a new value to a variable. Modifications take
5005 * Automatic SunOS shared library reading
5007 When you run your program, GDB automatically determines where its
5008 shared libraries (if any) have been loaded, and reads their symbols.
5009 The `share' command is no longer needed. This also works when
5010 examining core files.
5014 You can specify the number of lines that the `list' command shows.
5017 * New machines supported (host and target)
5019 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5020 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5021 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5023 * New hosts supported (not targets)
5025 IBM RT/PC: romp-ibm-aix or rtpc
5027 * New targets supported (not hosts)
5029 AMD 29000 embedded with COFF a29k-none-coff
5030 AMD 29000 embedded with a.out a29k-none-aout
5031 Ultracomputer remote kernel debug a29k-nyu-kern
5033 * New remote interfaces
5039 *** Changes in GDB-4.0:
5043 Wide output is wrapped at good places to make the output more readable.
5045 Gdb now supports cross-debugging from a host machine of one type to a
5046 target machine of another type. Communication with the target system
5047 is over serial lines. The ``target'' command handles connecting to the
5048 remote system; the ``load'' command will download a program into the
5049 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5050 also supports debugging of realtime processes running under VxWorks,
5051 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5052 stub on the target system.
5054 New CPUs supported include the AMD 29000 and Intel 960.
5056 GDB now reads object files and symbol tables via a ``binary file''
5057 library, which allows a single copy of GDB to debug programs of multiple
5058 object file types such as a.out and coff.
5060 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5061 refcard.dvi and refcard.ps are available to format it).
5064 * Control-Variable user interface simplified
5066 All variables that control the operation of the debugger can be set
5067 by the ``set'' command, and displayed by the ``show'' command.
5069 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5070 ``Show prompt'' produces the response:
5071 Gdb's prompt is new-gdb=>.
5073 What follows are the NEW set commands. The command ``help set'' will
5074 print a complete list of old and new set commands. ``help set FOO''
5075 will give a longer description of the variable FOO. ``show'' will show
5076 all of the variable descriptions and their current settings.
5078 confirm on/off: Enables warning questions for operations that are
5079 hard to recover from, e.g. rerunning the program while
5080 it is already running. Default is ON.
5082 editing on/off: Enables EMACS style command line editing
5083 of input. Previous lines can be recalled with
5084 control-P, the current line can be edited with control-B,
5085 you can search for commands with control-R, etc.
5088 history filename NAME: NAME is where the gdb command history
5089 will be stored. The default is .gdb_history,
5090 or the value of the environment variable
5093 history size N: The size, in commands, of the command history. The
5094 default is 256, or the value of the environment variable
5097 history save on/off: If this value is set to ON, the history file will
5098 be saved after exiting gdb. If set to OFF, the
5099 file will not be saved. The default is OFF.
5101 history expansion on/off: If this value is set to ON, then csh-like
5102 history expansion will be performed on
5103 command line input. The default is OFF.
5105 radix N: Sets the default radix for input and output. It can be set
5106 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5107 in the current radix, so "set radix 10" is always a no-op.
5109 height N: This integer value is the number of lines on a page. Default
5110 is 24, the current `stty rows'' setting, or the ``li#''
5111 setting from the termcap entry matching the environment
5114 width N: This integer value is the number of characters on a line.
5115 Default is 80, the current `stty cols'' setting, or the ``co#''
5116 setting from the termcap entry matching the environment
5119 Note: ``set screensize'' is obsolete. Use ``set height'' and
5120 ``set width'' instead.
5122 print address on/off: Print memory addresses in various command displays,
5123 such as stack traces and structure values. Gdb looks
5124 more ``symbolic'' if you turn this off; it looks more
5125 ``machine level'' with it on. Default is ON.
5127 print array on/off: Prettyprint arrays. New convenient format! Default
5130 print demangle on/off: Print C++ symbols in "source" form if on,
5133 print asm-demangle on/off: Same, for assembler level printouts
5136 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5139 * Support for Epoch Environment.
5141 The epoch environment is a version of Emacs v18 with windowing. One
5142 new command, ``inspect'', is identical to ``print'', except that if you
5143 are running in the epoch environment, the value is printed in its own
5147 * Support for Shared Libraries
5149 GDB can now debug programs and core files that use SunOS shared libraries.
5150 Symbols from a shared library cannot be referenced
5151 before the shared library has been linked with the program (this
5152 happens after you type ``run'' and before the function main() is entered).
5153 At any time after this linking (including when examining core files
5154 from dynamically linked programs), gdb reads the symbols from each
5155 shared library when you type the ``sharedlibrary'' command.
5156 It can be abbreviated ``share''.
5158 sharedlibrary REGEXP: Load shared object library symbols for files
5159 matching a unix regular expression. No argument
5160 indicates to load symbols for all shared libraries.
5162 info sharedlibrary: Status of loaded shared libraries.
5167 A watchpoint stops execution of a program whenever the value of an
5168 expression changes. Checking for this slows down execution
5169 tremendously whenever you are in the scope of the expression, but is
5170 quite useful for catching tough ``bit-spreader'' or pointer misuse
5171 problems. Some machines such as the 386 have hardware for doing this
5172 more quickly, and future versions of gdb will use this hardware.
5174 watch EXP: Set a watchpoint (breakpoint) for an expression.
5176 info watchpoints: Information about your watchpoints.
5178 delete N: Deletes watchpoint number N (same as breakpoints).
5179 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5180 enable N: Re-enables watchpoint number N (same as breakpoints).
5183 * C++ multiple inheritance
5185 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5188 * C++ exception handling
5190 Gdb now supports limited C++ exception handling. Besides the existing
5191 ability to breakpoint on an exception handler, gdb can breakpoint on
5192 the raising of an exception (before the stack is peeled back to the
5195 catch FOO: If there is a FOO exception handler in the dynamic scope,
5196 set a breakpoint to catch exceptions which may be raised there.
5197 Multiple exceptions (``catch foo bar baz'') may be caught.
5199 info catch: Lists all exceptions which may be caught in the
5200 current stack frame.
5203 * Minor command changes
5205 The command ``call func (arg, arg, ...)'' now acts like the print
5206 command, except it does not print or save a value if the function's result
5207 is void. This is similar to dbx usage.
5209 The ``up'' and ``down'' commands now always print the frame they end up
5210 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5211 frames without printing.
5213 * New directory command
5215 'dir' now adds directories to the FRONT of the source search path.
5216 The path starts off empty. Source files that contain debug information
5217 about the directory in which they were compiled can be found even
5218 with an empty path; Sun CC and GCC include this information. If GDB can't
5219 find your source file in the current directory, type "dir .".
5221 * Configuring GDB for compilation
5223 For normal use, type ``./configure host''. See README or gdb.texinfo
5226 GDB now handles cross debugging. If you are remotely debugging between
5227 two different machines, type ``./configure host -target=targ''.
5228 Host is the machine where GDB will run; targ is the machine
5229 where the program that you are debugging will run.