1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.5
6 * If the configured location of system.gdbinit file (as given by the
7 --with-system-gdbinit option at configure time) is in the
8 data-directory (as specified by --with-gdb-datadir at configure
9 time) or in one of its subdirectories, then GDB will look for the
10 system-wide init file in the directory specified by the
11 --data-directory command-line option.
13 * New command line options:
15 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
16 other initialization files, unlike -nx which disables all of them.
18 * The 'ptype' and 'whatis' commands now accept an argument to control
23 ** Vectors can be created with gdb.Type.vector.
25 ** Python's atexit.register now works in GDB.
27 ** Types can be pretty-printed via a Python API.
29 * New Python-based convenience functions:
31 ** $_memeq(buf1, buf2, length)
32 ** $_streq(str1, str2)
34 ** $_regex(str, regex)
36 * The 'cd' command now defaults to using '~' (the home directory) if not
39 * The command 'forward-search' can now be abbreviated as 'fo'.
41 * New configure options
43 --enable-libmcheck/--disable-libmcheck
44 By default, development versions are built with -lmcheck on hosts
45 that support it, in order to help track memory corruption issues.
46 Release versions, on the other hand, are built without -lmcheck
47 by default. The --enable-libmcheck/--disable-libmcheck configure
48 options allow the user to override that default.
50 * New commands (for set/show, see "New options" below)
53 List the BFDs known to GDB.
55 python-interactive [command]
57 Start a Python interactive prompt, or evaluate the optional command
58 and print the result of expressions.
61 "py" is a new alias for "python".
63 enable type-printer [name]...
64 disable type-printer [name]...
65 Enable or disable type printers.
69 ** For the Renesas Super-H architecture, the "regs" command has been removed
70 (has been deprecated in GDB 7.5), and "info all-registers" should be used
75 set print type methods (on|off)
76 show print type methods
77 Control whether method declarations are displayed by "ptype".
78 The default is to show them.
80 set print type typedefs (on|off)
81 show print type typedefs
82 Control whether typedef definitions are displayed by "ptype".
83 The default is to show them.
87 ** Command parameter changes are now notified using new async record
89 ** Trace frame changes caused by command "tfind" are now notified using
90 new async record "=traceframe-changed".
91 ** The creation and deletion of trace state variables are now notified
92 using new async records "=tsv-created" and "=tsv-deleted".
93 ** The start and stop of process record are now notified using new
94 async record "=record-started" and "=record-stopped".
95 ** Memory changes are now notified using new async record
97 ** The data-disassemble command response will include a "fullname" field
98 containing the absolute file name when GDB can determine it and source
100 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
101 command, to allow pattern filling of memory areas.
103 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
104 You must have the LZMA library available when configuring GDB for this
105 feature to be enabled. For more information, see:
106 http://fedoraproject.org/wiki/Features/MiniDebugInfo
108 *** Changes in GDB 7.5
110 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
111 for more x32 ABI info.
113 * GDB now supports access to MIPS DSP registers on Linux targets.
115 * GDB now supports debugging microMIPS binaries.
117 * The "info os" command on GNU/Linux can now display information on
118 several new classes of objects managed by the operating system:
119 "info os procgroups" lists process groups
120 "info os files" lists file descriptors
121 "info os sockets" lists internet-domain sockets
122 "info os shm" lists shared-memory regions
123 "info os semaphores" lists semaphores
124 "info os msg" lists message queues
125 "info os modules" lists loaded kernel modules
127 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
128 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
129 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
130 options and inspect the probe arguments using the new $_probe_arg family
131 of convenience variables. You can obtain more information about SystemTap
132 in <http://sourceware.org/systemtap/>.
134 * GDB now supports reversible debugging on ARM, it allows you to
135 debug basic ARM and THUMB instructions, and provides
136 record/replay support.
138 * The option "symbol-reloading" has been deleted as it is no longer used.
142 ** GDB commands implemented in Python can now be put in command class
145 ** The "maint set python print-stack on|off" is now deleted.
147 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
148 apply "flag enum"-style pretty-printing to any enum.
150 ** gdb.lookup_symbol can now work when there is no current frame.
152 ** gdb.Symbol now has a 'line' attribute, holding the line number in
153 the source at which the symbol was defined.
155 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
156 method 'value'. The former indicates whether the symbol needs a
157 frame in order to compute its value, and the latter computes the
160 ** A new method 'referenced_value' on gdb.Value objects which can
161 dereference pointer as well as C++ reference values.
163 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
164 which return the global and static blocks (as gdb.Block objects),
165 of the underlying symbol table, respectively.
167 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
168 object associated with a PC value.
170 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
171 of the address range occupied by code for the current source line.
173 * Go language support.
174 GDB now supports debugging programs written in the Go programming
177 * GDBserver now supports stdio connections.
178 E.g. (gdb) target remote | ssh myhost gdbserver - hello
180 * The binary "gdbtui" can no longer be built or installed.
181 Use "gdb -tui" instead.
183 * GDB will now print "flag" enums specially. A flag enum is one where
184 all the enumerator values have no bits in common when pairwise
185 "and"ed. When printing a value whose type is a flag enum, GDB will
186 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
187 (gdb) print (enum E) 3
190 * The filename part of a linespec will now match trailing components
191 of a source file name. For example, "break gcc/expr.c:1000" will
192 now set a breakpoint in build/gcc/expr.c, but not
195 * The "info proc" and "generate-core-file" commands will now also
196 work on remote targets connected to GDBserver on Linux.
198 * The command "info catch" has been removed. It has been disabled
201 * The "catch exception" and "catch assert" commands now accept
202 a condition at the end of the command, much like the "break"
203 command does. For instance:
205 (gdb) catch exception Constraint_Error if Barrier = True
207 Previously, it was possible to add a condition to such catchpoints,
208 but it had to be done as a second step, after the catchpoint had been
209 created, using the "condition" command.
211 * The "info static-tracepoint-marker" command will now also work on
212 native Linux targets with in-process agent.
214 * GDB can now set breakpoints on inlined functions.
216 * The .gdb_index section has been updated to include symbols for
217 inlined functions. GDB will ignore older .gdb_index sections by
218 default, which could cause symbol files to be loaded more slowly
219 until their .gdb_index sections can be recreated. The new command
220 "set use-deprecated-index-sections on" will cause GDB to use any older
221 .gdb_index sections it finds. This will restore performance, but the
222 ability to set breakpoints on inlined functions will be lost in symbol
223 files with older .gdb_index sections.
225 The .gdb_index section has also been updated to record more information
226 about each symbol. This speeds up the "info variables", "info functions"
227 and "info types" commands when used with programs having the .gdb_index
228 section, as well as speeding up debugging with shared libraries using
229 the .gdb_index section.
231 * Ada support for GDB/MI Variable Objects has been added.
233 * GDB can now support 'breakpoint always-inserted mode' in 'record'
238 ** New command -info-os is the MI equivalent of "info os".
240 ** Output logs ("set logging" and related) now include MI output.
244 ** "set use-deprecated-index-sections on|off"
245 "show use-deprecated-index-sections on|off"
246 Controls the use of deprecated .gdb_index sections.
248 ** "catch load" and "catch unload" can be used to stop when a shared
249 library is loaded or unloaded, respectively.
251 ** "enable count" can be used to auto-disable a breakpoint after
254 ** "info vtbl" can be used to show the virtual method tables for
255 C++ and Java objects.
257 ** "explore" and its sub commands "explore value" and "explore type"
258 can be used to reccursively explore values and types of
259 expressions. These commands are available only if GDB is
260 configured with '--with-python'.
262 ** "info auto-load" shows status of all kinds of auto-loaded files,
263 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
264 sequences of commands files, "info auto-load python-scripts"
265 shows status of auto-loading Python script files,
266 "info auto-load local-gdbinit" shows status of loading init file
267 (.gdbinit) from current directory and "info auto-load libthread-db" shows
268 status of inferior specific thread debugging shared library loading.
270 ** "info auto-load-scripts", "set auto-load-scripts on|off"
271 and "show auto-load-scripts" commands have been deprecated, use their
272 "info auto-load python-scripts", "set auto-load python-scripts on|off"
273 and "show auto-load python-scripts" counterparts instead.
275 ** "dprintf location,format,args..." creates a dynamic printf, which
276 is basically a breakpoint that does a printf and immediately
277 resumes your program's execution, so it is like a printf that you
278 can insert dynamically at runtime instead of at compiletime.
280 ** "set print symbol"
282 Controls whether GDB attempts to display the symbol, if any,
283 corresponding to addresses it prints. This defaults to "on", but
284 you can set it to "off" to restore GDB's previous behavior.
286 * Deprecated commands
288 ** For the Renesas Super-H architecture, the "regs" command has been
289 deprecated, and "info all-registers" should be used instead.
293 Renesas RL78 rl78-*-elf
294 HP OpenVMS ia64 ia64-hp-openvms*
296 * GDBserver supports evaluation of breakpoint conditions. When
297 support is advertised by GDBserver, GDB may be told to send the
298 breakpoint conditions in bytecode form to GDBserver. GDBserver
299 will only report the breakpoint trigger to GDB when its condition
305 show mips compression
306 Select the compressed ISA encoding used in functions that have no symbol
307 information available. The encoding can be set to either of:
310 and is updated automatically from ELF file flags if available.
312 set breakpoint condition-evaluation
313 show breakpoint condition-evaluation
314 Control whether breakpoint conditions are evaluated by GDB ("host") or by
315 GDBserver ("target"). Default option "auto" chooses the most efficient
317 This option can improve debugger efficiency depending on the speed of the
321 Disable auto-loading globally.
324 Show auto-loading setting of all kinds of auto-loaded files.
326 set auto-load gdb-scripts on|off
327 show auto-load gdb-scripts
328 Control auto-loading of GDB canned sequences of commands files.
330 set auto-load python-scripts on|off
331 show auto-load python-scripts
332 Control auto-loading of Python script files.
334 set auto-load local-gdbinit on|off
335 show auto-load local-gdbinit
336 Control loading of init file (.gdbinit) from current directory.
338 set auto-load libthread-db on|off
339 show auto-load libthread-db
340 Control auto-loading of inferior specific thread debugging shared library.
342 set auto-load scripts-directory <dir1>[:<dir2>...]
343 show auto-load scripts-directory
344 Set a list of directories from which to load auto-loaded scripts.
345 Automatically loaded Python scripts and GDB scripts are located in one
346 of the directories listed by this option.
347 The delimiter (':' above) may differ according to the host platform.
349 set auto-load safe-path <dir1>[:<dir2>...]
350 show auto-load safe-path
351 Set a list of directories from which it is safe to auto-load files.
352 The delimiter (':' above) may differ according to the host platform.
354 set debug auto-load on|off
356 Control display of debugging info for auto-loading the files above.
358 set dprintf-style gdb|call|agent
360 Control the way in which a dynamic printf is performed; "gdb"
361 requests a GDB printf command, while "call" causes dprintf to call a
362 function in the inferior. "agent" requests that the target agent
363 (such as GDBserver) do the printing.
365 set dprintf-function <expr>
366 show dprintf-function
367 set dprintf-channel <expr>
369 Set the function and optional first argument to the call when using
370 the "call" style of dynamic printf.
372 set disconnected-dprintf on|off
373 show disconnected-dprintf
374 Control whether agent-style dynamic printfs continue to be in effect
375 after GDB disconnects.
377 * New configure options
380 Configure default value for the 'set auto-load scripts-directory'
381 setting above. It defaults to '$debugdir:$datadir/auto-load',
382 $debugdir representing global debugging info directories (available
383 via 'show debug-file-directory') and $datadir representing GDB's data
384 directory (available via 'show data-directory').
386 --with-auto-load-safe-path
387 Configure default value for the 'set auto-load safe-path' setting
388 above. It defaults to the --with-auto-load-dir setting.
390 --without-auto-load-safe-path
391 Set 'set auto-load safe-path' to '/', effectively disabling this
396 z0/z1 conditional breakpoints extension
398 The z0/z1 breakpoint insertion packets have been extended to carry
399 a list of conditional expressions over to the remote stub depending on the
400 condition evaluation mode. The use of this extension can be controlled
401 via the "set remote conditional-breakpoints-packet" command.
405 Specify the signals which the remote stub may pass to the debugged
406 program without GDB involvement.
408 * New command line options
410 --init-command=FILE, -ix Like --command, -x but execute it
411 before loading inferior.
412 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
413 execute it before loading inferior.
415 *** Changes in GDB 7.4
417 * GDB now handles ambiguous linespecs more consistently; the existing
418 FILE:LINE support has been expanded to other types of linespecs. A
419 breakpoint will now be set on all matching locations in all
420 inferiors, and locations will be added or removed according to
423 * GDB now allows you to skip uninteresting functions and files when
424 stepping with the "skip function" and "skip file" commands.
426 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
427 and "show remote hardware-watchpoint-length-limit". These allows to
428 set or show the maximum length limit (in bytes) of a remote
429 target hardware watchpoint.
431 This allows e.g. to use "unlimited" hardware watchpoints with the
432 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
433 watchpoints are slower than real hardware watchpoints but are
434 significantly faster than gdb software watchpoints.
438 ** The register_pretty_printer function in module gdb.printing now takes
439 an optional `replace' argument. If True, the new printer replaces any
442 ** The "maint set python print-stack on|off" command has been
443 deprecated and will be deleted in GDB 7.5.
444 A new command: "set python print-stack none|full|message" has
445 replaced it. Additionally, the default for "print-stack" is
446 now "message", which just prints the error message without
449 ** A prompt substitution hook (prompt_hook) is now available to the
452 ** A new Python module, gdb.prompt has been added to the GDB Python
453 modules library. This module provides functionality for
454 escape sequences in prompts (used by set/show
455 extended-prompt). These escape sequences are replaced by their
458 ** Python commands and convenience-functions located in
459 'data-directory'/python/gdb/command and
460 'data-directory'/python/gdb/function are now automatically loaded
463 ** Blocks now provide four new attributes. global_block and
464 static_block will return the global and static blocks
465 respectively. is_static and is_global are boolean attributes
466 that indicate if the block is one of those two types.
468 ** Symbols now provide the "type" attribute, the type of the symbol.
470 ** The "gdb.breakpoint" function has been deprecated in favor of
473 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
474 of a function. This class is based on the "finish" command
475 available in the CLI.
477 ** Type objects for struct and union types now allow access to
478 the fields using standard Python dictionary (mapping) methods.
479 For example, "some_type['myfield']" now works, as does
482 ** A new event "gdb.new_objfile" has been added, triggered by loading a
485 ** A new function, "deep_items" has been added to the gdb.types
486 module in the GDB Python modules library. This function returns
487 an iterator over the fields of a struct or union type. Unlike
488 the standard Python "iteritems" method, it will recursively traverse
489 any anonymous fields.
493 ** "*stopped" events can report several new "reason"s, such as
496 ** Breakpoint changes are now notified using new async records, like
497 "=breakpoint-modified".
499 ** New command -ada-task-info.
501 * libthread-db-search-path now supports two special values: $sdir and $pdir.
502 $sdir specifies the default system locations of shared libraries.
503 $pdir specifies the directory where the libpthread used by the application
506 GDB no longer looks in $sdir and $pdir after it has searched the directories
507 mentioned in libthread-db-search-path. If you want to search those
508 directories, they must be specified in libthread-db-search-path.
509 The default value of libthread-db-search-path on GNU/Linux and Solaris
510 systems is now "$sdir:$pdir".
512 $pdir is not supported by gdbserver, it is currently ignored.
513 $sdir is supported by gdbserver.
515 * New configure option --with-iconv-bin.
516 When using the internationalization support like the one in the GNU C
517 library, GDB will invoke the "iconv" program to get a list of supported
518 character sets. If this program lives in a non-standard location, one can
519 use this option to specify where to find it.
521 * When natively debugging programs on PowerPC BookE processors running
522 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
523 watchpoints, which specify a mask in addition to an address to watch.
524 The mask specifies that some bits of an address (the bits which are
525 reset in the mask) should be ignored when matching the address accessed
526 by the inferior against the watchpoint address. See the "PowerPC Embedded"
527 section in the user manual for more details.
529 * The new option --once causes GDBserver to stop listening for connections once
530 the first connection is made. The listening port used by GDBserver will
531 become available after that.
533 * New commands "info macros" and "alias" have been added.
535 * New function parameters suffix @entry specifies value of function parameter
536 at the time the function got called. Entry values are available only since
542 "!" is now an alias of the "shell" command.
543 Note that no space is needed between "!" and SHELL COMMAND.
547 watch EXPRESSION mask MASK_VALUE
548 The watch command now supports the mask argument which allows creation
549 of masked watchpoints, if the current architecture supports this feature.
551 info auto-load-scripts [REGEXP]
552 This command was formerly named "maintenance print section-scripts".
553 It is now generally useful and is no longer a maintenance-only command.
555 info macro [-all] [--] MACRO
556 The info macro command has new options `-all' and `--'. The first for
557 printing all definitions of a macro. The second for explicitly specifying
558 the end of arguments and the beginning of the macro name in case the macro
559 name starts with a hyphen.
561 collect[/s] EXPRESSIONS
562 The tracepoint collect command now takes an optional modifier "/s"
563 that directs it to dereference pointer-to-character types and
564 collect the bytes of memory up to a zero byte. The behavior is
565 similar to what you see when you use the regular print command on a
566 string. An optional integer following the "/s" sets a bound on the
567 number of bytes that will be collected.
570 The trace start command now interprets any supplied arguments as a
571 note to be recorded with the trace run, with an effect similar to
572 setting the variable trace-notes.
575 The trace stop command now interprets any arguments as a note to be
576 mentioned along with the tstatus report that the trace was stopped
577 with a command. The effect is similar to setting the variable
580 * Tracepoints can now be enabled and disabled at any time after a trace
581 experiment has been started using the standard "enable" and "disable"
582 commands. It is now possible to start a trace experiment with no enabled
583 tracepoints; GDB will display a warning, but will allow the experiment to
584 begin, assuming that tracepoints will be enabled as needed while the trace
587 * Fast tracepoints on 32-bit x86-architectures can now be placed at
588 locations with 4-byte instructions, when they were previously
589 limited to locations with instructions of 5 bytes or longer.
593 set debug dwarf2-read
594 show debug dwarf2-read
595 Turns on or off display of debugging messages related to reading
596 DWARF debug info. The default is off.
598 set debug symtab-create
599 show debug symtab-create
600 Turns on or off display of debugging messages related to symbol table
601 creation. The default is off.
605 Set the GDB prompt, and allow escape sequences to be inserted to
606 display miscellaneous information (see 'help set extended-prompt'
607 for the list of sequences). This prompt (and any information
608 accessed through the escape sequences) is updated every time the
611 set print entry-values (both|compact|default|if-needed|no|only|preferred)
612 show print entry-values
613 Set printing of frame argument values at function entry. In some cases
614 GDB can determine the value of function argument which was passed by the
615 function caller, even if the value was modified inside the called function.
617 set debug entry-values
618 show debug entry-values
619 Control display of debugging info for determining frame argument values at
620 function entry and virtual tail call frames.
622 set basenames-may-differ
623 show basenames-may-differ
624 Set whether a source file may have multiple base names.
625 (A "base name" is the name of a file with the directory part removed.
626 Example: The base name of "/home/user/hello.c" is "hello.c".)
627 If set, GDB will canonicalize file names (e.g., expand symlinks)
628 before comparing them. Canonicalization is an expensive operation,
629 but it allows the same file be known by more than one base name.
630 If not set (the default), all source files are assumed to have just
631 one base name, and gdb will do file name comparisons more efficiently.
637 Set a user name and notes for the current and any future trace runs.
638 This is useful for long-running and/or disconnected traces, to
639 inform others (or yourself) as to who is running the trace, supply
640 contact information, or otherwise explain what is going on.
643 show trace-stop-notes
644 Set a note attached to the trace run, that is displayed when the
645 trace has been stopped by a tstop command. This is useful for
646 instance as an explanation, if you are stopping a trace run that was
647 started by someone else.
653 Dynamically enable a tracepoint in a started trace experiment.
657 Dynamically disable a tracepoint in a started trace experiment.
661 Set the user and notes of the trace run.
665 Query the current status of a tracepoint.
669 Query the minimum length of instruction at which a fast tracepoint may
672 * Dcache size (number of lines) and line-size are now runtime-configurable
673 via "set dcache line" and "set dcache line-size" commands.
677 Texas Instruments TMS320C6x tic6x-*-*
681 Renesas RL78 rl78-*-elf
683 *** Changes in GDB 7.3.1
685 * The build failure for NetBSD and OpenBSD targets have now been fixed.
687 *** Changes in GDB 7.3
689 * GDB has a new command: "thread find [REGEXP]".
690 It finds the thread id whose name, target id, or thread extra info
691 matches the given regular expression.
693 * The "catch syscall" command now works on mips*-linux* targets.
695 * The -data-disassemble MI command now supports modes 2 and 3 for
696 dumping the instruction opcodes.
698 * New command line options
700 -data-directory DIR Specify DIR as the "data-directory".
701 This is mostly for testing purposes.
703 * The "maint set python auto-load on|off" command has been renamed to
704 "set auto-load-scripts on|off".
706 * GDB has a new command: "set directories".
707 It is like the "dir" command except that it replaces the
708 source path list instead of augmenting it.
710 * GDB now understands thread names.
712 On GNU/Linux, "info threads" will display the thread name as set by
713 prctl or pthread_setname_np.
715 There is also a new command, "thread name", which can be used to
716 assign a name internally for GDB to display.
719 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
720 has been integrated into GDB.
724 ** The function gdb.Write now accepts an optional keyword 'stream'.
725 This keyword, when provided, will direct the output to either
726 stdout, stderr, or GDB's logging output.
728 ** Parameters can now be be sub-classed in Python, and in particular
729 you may implement the get_set_doc and get_show_doc functions.
730 This improves how Parameter set/show documentation is processed
731 and allows for more dynamic content.
733 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
734 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
735 have an is_valid method.
737 ** Breakpoints can now be sub-classed in Python, and in particular
738 you may implement a 'stop' function that is executed each time
739 the inferior reaches that breakpoint.
741 ** New function gdb.lookup_global_symbol looks up a global symbol.
743 ** GDB values in Python are now callable if the value represents a
744 function. For example, if 'some_value' represents a function that
745 takes two integer parameters and returns a value, you can call
746 that function like so:
748 result = some_value (10,20)
750 ** Module gdb.types has been added.
751 It contains a collection of utilities for working with gdb.Types objects:
752 get_basic_type, has_field, make_enum_dict.
754 ** Module gdb.printing has been added.
755 It contains utilities for writing and registering pretty-printers.
756 New classes: PrettyPrinter, SubPrettyPrinter,
757 RegexpCollectionPrettyPrinter.
758 New function: register_pretty_printer.
760 ** New commands "info pretty-printers", "enable pretty-printer" and
761 "disable pretty-printer" have been added.
763 ** gdb.parameter("directories") is now available.
765 ** New function gdb.newest_frame returns the newest frame in the
768 ** The gdb.InferiorThread class has a new "name" attribute. This
769 holds the thread's name.
771 ** Python Support for Inferior events.
772 Python scripts can add observers to be notified of events
773 occurring in the process being debugged.
774 The following events are currently supported:
775 - gdb.events.cont Continue event.
776 - gdb.events.exited Inferior exited event.
777 - gdb.events.stop Signal received, and Breakpoint hit events.
781 ** GDB now puts template parameters in scope when debugging in an
782 instantiation. For example, if you have:
784 template<int X> int func (void) { return X; }
786 then if you step into func<5>, "print X" will show "5". This
787 feature requires proper debuginfo support from the compiler; it
788 was added to GCC 4.5.
790 ** The motion commands "next", "finish", "until", and "advance" now
791 work better when exceptions are thrown. In particular, GDB will
792 no longer lose control of the inferior; instead, the GDB will
793 stop the inferior at the point at which the exception is caught.
794 This functionality requires a change in the exception handling
795 code that was introduced in GCC 4.5.
797 * GDB now follows GCC's rules on accessing volatile objects when
798 reading or writing target state during expression evaluation.
799 One notable difference to prior behavior is that "print x = 0"
800 no longer generates a read of x; the value of the assignment is
801 now always taken directly from the value being assigned.
803 * GDB now has some support for using labels in the program's source in
804 linespecs. For instance, you can use "advance label" to continue
805 execution to a label.
807 * GDB now has support for reading and writing a new .gdb_index
808 section. This section holds a fast index of DWARF debugging
809 information and can be used to greatly speed up GDB startup and
810 operation. See the documentation for `save gdb-index' for details.
812 * The "watch" command now accepts an optional "-location" argument.
813 When used, this causes GDB to watch the memory referred to by the
814 expression. Such a watchpoint is never deleted due to it going out
817 * GDB now supports thread debugging of core dumps on GNU/Linux.
819 GDB now activates thread debugging using the libthread_db library
820 when debugging GNU/Linux core dumps, similarly to when debugging
821 live processes. As a result, when debugging a core dump file, GDB
822 is now able to display pthread_t ids of threads. For example, "info
823 threads" shows the same output as when debugging the process when it
824 was live. In earlier releases, you'd see something like this:
827 * 1 LWP 6780 main () at main.c:10
829 While now you see this:
832 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
834 It is also now possible to inspect TLS variables when debugging core
837 When debugging a core dump generated on a machine other than the one
838 used to run GDB, you may need to point GDB at the correct
839 libthread_db library with the "set libthread-db-search-path"
840 command. See the user manual for more details on this command.
842 * When natively debugging programs on PowerPC BookE processors running
843 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
844 which stop execution of the inferior whenever it executes an instruction
845 at any address within the specified range. See the "PowerPC Embedded"
846 section in the user manual for more details.
848 * New features in the GDB remote stub, GDBserver
850 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
851 and i686 LynxOS (version 5.x).
853 ** GDBserver is now supported on Blackfin Linux.
855 * New native configurations
857 ia64 HP-UX ia64-*-hpux*
861 Analog Devices, Inc. Blackfin Processor bfin-*
863 * Ada task switching is now supported on sparc-elf targets when
864 debugging a program using the Ravenscar Profile. For more information,
865 see the "Tasking Support when using the Ravenscar Profile" section
866 in the GDB user manual.
868 * Guile support was removed.
870 * New features in the GNU simulator
872 ** The --map-info flag lists all known core mappings.
874 ** CFI flashes may be simulated via the "cfi" device.
876 *** Changes in GDB 7.2
878 * Shared library support for remote targets by default
880 When GDB is configured for a generic, non-OS specific target, like
881 for example, --target=arm-eabi or one of the many *-*-elf targets,
882 GDB now queries remote stubs for loaded shared libraries using the
883 `qXfer:libraries:read' packet. Previously, shared library support
884 was always disabled for such configurations.
888 ** Argument Dependent Lookup (ADL)
890 In C++ ADL lookup directs function search to the namespaces of its
891 arguments even if the namespace has not been imported.
901 Here the compiler will search for `foo' in the namespace of 'b'
902 and find A::foo. GDB now supports this. This construct is commonly
903 used in the Standard Template Library for operators.
905 ** Improved User Defined Operator Support
907 In addition to member operators, GDB now supports lookup of operators
908 defined in a namespace and imported with a `using' directive, operators
909 defined in the global scope, operators imported implicitly from an
910 anonymous namespace, and the ADL operators mentioned in the previous
912 GDB now also supports proper overload resolution for all the previously
913 mentioned flavors of operators.
915 ** static const class members
917 Printing of static const class members that are initialized in the
918 class definition has been fixed.
920 * Windows Thread Information Block access.
922 On Windows targets, GDB now supports displaying the Windows Thread
923 Information Block (TIB) structure. This structure is visible either
924 by using the new command `info w32 thread-information-block' or, by
925 dereferencing the new convenience variable named `$_tlb', a
926 thread-specific pointer to the TIB. This feature is also supported
927 when remote debugging using GDBserver.
931 Static tracepoints are calls in the user program into a tracing
932 library. One such library is a port of the LTTng kernel tracer to
933 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
934 When debugging with GDBserver, GDB now supports combining the GDB
935 tracepoint machinery with such libraries. For example: the user can
936 use GDB to probe a static tracepoint marker (a call from the user
937 program into the tracing library) with the new "strace" command (see
938 "New commands" below). This creates a "static tracepoint" in the
939 breakpoint list, that can be manipulated with the same feature set
940 as fast and regular tracepoints. E.g., collect registers, local and
941 global variables, collect trace state variables, and define
942 tracepoint conditions. In addition, the user can collect extra
943 static tracepoint marker specific data, by collecting the new
944 $_sdata internal variable. When analyzing the trace buffer, you can
945 inspect $_sdata like any other variable available to GDB. For more
946 information, see the "Tracepoints" chapter in GDB user manual. New
947 remote packets have been defined to support static tracepoints, see
948 the "New remote packets" section below.
950 * Better reconstruction of tracepoints after disconnected tracing
952 GDB will attempt to download the original source form of tracepoint
953 definitions when starting a trace run, and then will upload these
954 upon reconnection to the target, resulting in a more accurate
955 reconstruction of the tracepoints that are in use on the target.
959 You can now exercise direct control over the ways that GDB can
960 affect your program. For instance, you can disallow the setting of
961 breakpoints, so that the program can run continuously (assuming
962 non-stop mode). In addition, the "observer" variable is available
963 to switch all of the different controls; in observer mode, GDB
964 cannot affect the target's behavior at all, which is useful for
965 tasks like diagnosing live systems in the field.
967 * The new convenience variable $_thread holds the number of the
974 Return the address of the Windows Thread Information Block of a given thread.
978 In response to several of the tracepoint packets, the target may now
979 also respond with a number of intermediate `qRelocInsn' request
980 packets before the final result packet, to have GDB handle
981 relocating an instruction to execute at a different address. This
982 is particularly useful for stubs that support fast tracepoints. GDB
983 reports support for this feature in the qSupported packet.
987 List static tracepoint markers in the target program.
991 List static tracepoint markers at a given address in the target
994 qXfer:statictrace:read
996 Read the static trace data collected (by a `collect $_sdata'
997 tracepoint action). The remote stub reports support for this packet
998 to gdb's qSupported query.
1002 Send the current settings of GDB's permission flags.
1006 Send part of the source (textual) form of a tracepoint definition,
1007 which includes location, conditional, and action list.
1009 * The source command now accepts a -s option to force searching for the
1010 script in the source search path even if the script name specifies
1013 * New features in the GDB remote stub, GDBserver
1015 - GDBserver now support tracepoints (including fast tracepoints, and
1016 static tracepoints). The feature is currently supported by the
1017 i386-linux and amd64-linux builds. See the "Tracepoints support
1018 in gdbserver" section in the manual for more information.
1020 GDBserver JIT compiles the tracepoint's conditional agent
1021 expression bytecode into native code whenever possible for low
1022 overhead dynamic tracepoints conditionals. For such tracepoints,
1023 an expression that examines program state is evaluated when the
1024 tracepoint is reached, in order to determine whether to capture
1025 trace data. If the condition is simple and false, processing the
1026 tracepoint finishes very quickly and no data is gathered.
1028 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1029 for static tracepoints support.
1031 - GDBserver now supports x86_64 Windows 64-bit debugging.
1033 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1034 it understands register description.
1036 * The --batch flag now disables pagination and queries.
1038 * X86 general purpose registers
1040 GDB now supports reading/writing byte, word and double-word x86
1041 general purpose registers directly. This means you can use, say,
1042 $ah or $ax to refer, respectively, to the byte register AH and
1043 16-bit word register AX that are actually portions of the 32-bit
1044 register EAX or 64-bit register RAX.
1046 * The `commands' command now accepts a range of breakpoints to modify.
1047 A plain `commands' following a command that creates multiple
1048 breakpoints affects all the breakpoints set by that command. This
1049 applies to breakpoints set by `rbreak', and also applies when a
1050 single `break' command creates multiple breakpoints (e.g.,
1051 breakpoints on overloaded c++ functions).
1053 * The `rbreak' command now accepts a filename specification as part of
1054 its argument, limiting the functions selected by the regex to those
1055 in the specified file.
1057 * Support for remote debugging Windows and SymbianOS shared libraries
1058 from Unix hosts has been improved. Non Windows GDB builds now can
1059 understand target reported file names that follow MS-DOS based file
1060 system semantics, such as file names that include drive letters and
1061 use the backslash character as directory separator. This makes it
1062 possible to transparently use the "set sysroot" and "set
1063 solib-search-path" on Unix hosts to point as host copies of the
1064 target's shared libraries. See the new command "set
1065 target-file-system-kind" described below, and the "Commands to
1066 specify files" section in the user manual for more information.
1070 eval template, expressions...
1071 Convert the values of one or more expressions under the control
1072 of the string template to a command line, and call it.
1074 set target-file-system-kind unix|dos-based|auto
1075 show target-file-system-kind
1076 Set or show the assumed file system kind for target reported file
1079 save breakpoints <filename>
1080 Save all current breakpoint definitions to a file suitable for use
1081 in a later debugging session. To read the saved breakpoint
1082 definitions, use the `source' command.
1084 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1087 info static-tracepoint-markers
1088 Display information about static tracepoint markers in the target.
1090 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1091 Define a static tracepoint by probing a marker at the given
1092 function, line, address, or marker ID.
1096 Enable and disable observer mode.
1098 set may-write-registers on|off
1099 set may-write-memory on|off
1100 set may-insert-breakpoints on|off
1101 set may-insert-tracepoints on|off
1102 set may-insert-fast-tracepoints on|off
1103 set may-interrupt on|off
1104 Set individual permissions for GDB effects on the target. Note that
1105 some of these settings can have undesirable or surprising
1106 consequences, particularly when changed in the middle of a session.
1107 For instance, disabling the writing of memory can prevent
1108 breakpoints from being inserted, cause single-stepping to fail, or
1109 even crash your program, if you disable after breakpoints have been
1110 inserted. However, GDB should not crash.
1112 set record memory-query on|off
1113 show record memory-query
1114 Control whether to stop the inferior if memory changes caused
1115 by an instruction cannot be recorded.
1120 The disassemble command now supports "start,+length" form of two arguments.
1124 ** GDB now provides a new directory location, called the python directory,
1125 where Python scripts written for GDB can be installed. The location
1126 of that directory is <data-directory>/python, where <data-directory>
1127 is the GDB data directory. For more details, see section `Scripting
1128 GDB using Python' in the manual.
1130 ** The GDB Python API now has access to breakpoints, symbols, symbol
1131 tables, program spaces, inferiors, threads and frame's code blocks.
1132 Additionally, GDB Parameters can now be created from the API, and
1133 manipulated via set/show in the CLI.
1135 ** New functions gdb.target_charset, gdb.target_wide_charset,
1136 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1138 ** New exception gdb.GdbError.
1140 ** Pretty-printers are now also looked up in the current program space.
1142 ** Pretty-printers can now be individually enabled and disabled.
1144 ** GDB now looks for names of Python scripts to auto-load in a
1145 special section named `.debug_gdb_scripts', in addition to looking
1146 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1148 * Tracepoint actions were unified with breakpoint commands. In particular,
1149 there are no longer differences in "info break" output for breakpoints and
1150 tracepoints and the "commands" command can be used for both tracepoints and
1151 regular breakpoints.
1155 ARM Symbian arm*-*-symbianelf*
1157 * D language support.
1158 GDB now supports debugging programs written in the D programming
1161 * GDB now supports the extended ptrace interface for PowerPC which is
1162 available since Linux kernel version 2.6.34. This automatically enables
1163 any hardware breakpoints and additional hardware watchpoints available in
1164 the processor. The old ptrace interface exposes just one hardware
1165 watchpoint and no hardware breakpoints.
1167 * GDB is now able to use the Data Value Compare (DVC) register available on
1168 embedded PowerPC processors to implement in hardware simple watchpoint
1169 conditions of the form:
1171 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1173 This works in native GDB running on Linux kernels with the extended ptrace
1174 interface mentioned above.
1176 *** Changes in GDB 7.1
1180 ** Namespace Support
1182 GDB now supports importing of namespaces in C++. This enables the
1183 user to inspect variables from imported namespaces. Support for
1184 namepace aliasing has also been added. So, if a namespace is
1185 aliased in the current scope (e.g. namepace C=A; ) the user can
1186 print variables using the alias (e.g. (gdb) print C::x).
1190 All known bugs relating to the printing of virtual base class were
1191 fixed. It is now possible to call overloaded static methods using a
1196 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1197 and reinterpret_cast<> are now handled by the C++ expression parser.
1201 Xilinx MicroBlaze microblaze-*-*
1206 Xilinx MicroBlaze microblaze
1209 * Multi-program debugging.
1211 GDB now has support for multi-program (a.k.a. multi-executable or
1212 multi-exec) debugging. This allows for debugging multiple inferiors
1213 simultaneously each running a different program under the same GDB
1214 session. See "Debugging Multiple Inferiors and Programs" in the
1215 manual for more information. This implied some user visible changes
1216 in the multi-inferior support. For example, "info inferiors" now
1217 lists inferiors that are not running yet or that have exited
1218 already. See also "New commands" and "New options" below.
1220 * New tracing features
1222 GDB's tracepoint facility now includes several new features:
1224 ** Trace state variables
1226 GDB tracepoints now include support for trace state variables, which
1227 are variables managed by the target agent during a tracing
1228 experiment. They are useful for tracepoints that trigger each
1229 other, so for instance one tracepoint can count hits in a variable,
1230 and then a second tracepoint has a condition that is true when the
1231 count reaches a particular value. Trace state variables share the
1232 $-syntax of GDB convenience variables, and can appear in both
1233 tracepoint actions and condition expressions. Use the "tvariable"
1234 command to create, and "info tvariables" to view; see "Trace State
1235 Variables" in the manual for more detail.
1239 GDB now includes an option for defining fast tracepoints, which
1240 targets may implement more efficiently, such as by installing a jump
1241 into the target agent rather than a trap instruction. The resulting
1242 speedup can be by two orders of magnitude or more, although the
1243 tradeoff is that some program locations on some target architectures
1244 might not allow fast tracepoint installation, for instance if the
1245 instruction to be replaced is shorter than the jump. To request a
1246 fast tracepoint, use the "ftrace" command, with syntax identical to
1247 the regular trace command.
1249 ** Disconnected tracing
1251 It is now possible to detach GDB from the target while it is running
1252 a trace experiment, then reconnect later to see how the experiment
1253 is going. In addition, a new variable disconnected-tracing lets you
1254 tell the target agent whether to continue running a trace if the
1255 connection is lost unexpectedly.
1259 GDB now has the ability to save the trace buffer into a file, and
1260 then use that file as a target, similarly to you can do with
1261 corefiles. You can select trace frames, print data that was
1262 collected in them, and use tstatus to display the state of the
1263 tracing run at the moment that it was saved. To create a trace
1264 file, use "tsave <filename>", and to use it, do "target tfile
1267 ** Circular trace buffer
1269 You can ask the target agent to handle the trace buffer as a
1270 circular buffer, discarding the oldest trace frames to make room for
1271 newer ones, by setting circular-trace-buffer to on. This feature may
1272 not be available for all target agents.
1277 The disassemble command, when invoked with two arguments, now requires
1278 the arguments to be comma-separated.
1281 The info variables command now displays variable definitions. Files
1282 which only declare a variable are not shown.
1285 The source command is now capable of sourcing Python scripts.
1286 This feature is dependent on the debugger being build with Python
1289 Related to this enhancement is also the introduction of a new command
1290 "set script-extension" (see below).
1292 * New commands (for set/show, see "New options" below)
1294 record save [<FILENAME>]
1295 Save a file (in core file format) containing the process record
1296 execution log for replay debugging at a later time.
1298 record restore <FILENAME>
1299 Restore the process record execution log that was saved at an
1300 earlier time, for replay debugging.
1302 add-inferior [-copies <N>] [-exec <FILENAME>]
1305 clone-inferior [-copies <N>] [ID]
1306 Make a new inferior ready to execute the same program another
1307 inferior has loaded.
1312 maint info program-spaces
1313 List the program spaces loaded into GDB.
1315 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1316 show remote interrupt-sequence
1317 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1318 as the sequence to the remote target in order to interrupt the execution.
1319 Ctrl-C is a default. Some system prefers BREAK which is high level of
1320 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1321 Magic SysRq g. It is BREAK signal and character 'g'.
1323 set remote interrupt-on-connect [on | off]
1324 show remote interrupt-on-connect
1325 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1326 remote target when gdb connects to it. This is needed when you debug
1329 set remotebreak [on | off]
1331 Deprecated. Use "set/show remote interrupt-sequence" instead.
1333 tvariable $NAME [ = EXP ]
1334 Create or modify a trace state variable.
1337 List trace state variables and their values.
1339 delete tvariable $NAME ...
1340 Delete one or more trace state variables.
1343 Evaluate the given expressions without collecting anything into the
1344 trace buffer. (Valid in tracepoint actions only.)
1346 ftrace FN / FILE:LINE / *ADDR
1347 Define a fast tracepoint at the given function, line, or address.
1349 * New expression syntax
1351 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1352 GDB now parses 0b101010 identically with 42.
1356 set follow-exec-mode new|same
1357 show follow-exec-mode
1358 Control whether GDB reuses the same inferior across an exec call or
1359 creates a new one. This is useful to be able to restart the old
1360 executable after the inferior having done an exec call.
1362 set default-collect EXPR, ...
1363 show default-collect
1364 Define a list of expressions to be collected at each tracepoint.
1365 This is a useful way to ensure essential items are not overlooked,
1366 such as registers or a critical global variable.
1368 set disconnected-tracing
1369 show disconnected-tracing
1370 If set to 1, the target is instructed to continue tracing if it
1371 loses its connection to GDB. If 0, the target is to stop tracing
1374 set circular-trace-buffer
1375 show circular-trace-buffer
1376 If set to on, the target is instructed to use a circular trace buffer
1377 and discard the oldest trace frames instead of stopping the trace due
1378 to a full trace buffer. If set to off, the trace stops when the buffer
1379 fills up. Some targets may not support this.
1381 set script-extension off|soft|strict
1382 show script-extension
1383 If set to "off", the debugger does not perform any script language
1384 recognition, and all sourced files are assumed to be GDB scripts.
1385 If set to "soft" (the default), files are sourced according to
1386 filename extension, falling back to GDB scripts if the first
1388 If set to "strict", files are sourced according to filename extension.
1390 set ada trust-PAD-over-XVS on|off
1391 show ada trust-PAD-over-XVS
1392 If off, activate a workaround against a bug in the debugging information
1393 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1394 the GCC sources for more information about the GNAT encoding and
1395 PAD types in particular). It is always safe to set this option to
1396 off, but this introduces a slight performance penalty. The default
1399 * Python API Improvements
1401 ** GDB provides the new class gdb.LazyString. This is useful in
1402 some pretty-printing cases. The new method gdb.Value.lazy_string
1403 provides a simple way to create objects of this type.
1405 ** The fields returned by gdb.Type.fields now have an
1406 `is_base_class' attribute.
1408 ** The new method gdb.Type.range returns the range of an array type.
1410 ** The new method gdb.parse_and_eval can be used to parse and
1411 evaluate an expression.
1413 * New remote packets
1416 Define a trace state variable.
1419 Get the current value of a trace state variable.
1422 Set desired tracing behavior upon disconnection.
1425 Set the trace buffer to be linear or circular.
1428 Get data about the tracepoints currently in use.
1432 Process record now works correctly with hardware watchpoints.
1434 Multiple bug fixes have been made to the mips-irix port, making it
1435 much more reliable. In particular:
1436 - Debugging threaded applications is now possible again. Previously,
1437 GDB would hang while starting the program, or while waiting for
1438 the program to stop at a breakpoint.
1439 - Attaching to a running process no longer hangs.
1440 - An error occurring while loading a core file has been fixed.
1441 - Changing the value of the PC register now works again. This fixes
1442 problems observed when using the "jump" command, or when calling
1443 a function from GDB, or even when assigning a new value to $pc.
1444 - With the "finish" and "return" commands, the return value for functions
1445 returning a small array is now correctly printed.
1446 - It is now possible to break on shared library code which gets executed
1447 during a shared library init phase (code executed while executing
1448 their .init section). Previously, the breakpoint would have no effect.
1449 - GDB is now able to backtrace through the signal handler for
1450 non-threaded programs.
1452 PIE (Position Independent Executable) programs debugging is now supported.
1453 This includes debugging execution of PIC (Position Independent Code) shared
1454 libraries although for that, it should be possible to run such libraries as an
1457 *** Changes in GDB 7.0
1459 * GDB now has an interface for JIT compilation. Applications that
1460 dynamically generate code can create symbol files in memory and register
1461 them with GDB. For users, the feature should work transparently, and
1462 for JIT developers, the interface is documented in the GDB manual in the
1463 "JIT Compilation Interface" chapter.
1465 * Tracepoints may now be conditional. The syntax is as for
1466 breakpoints; either an "if" clause appended to the "trace" command,
1467 or the "condition" command is available. GDB sends the condition to
1468 the target for evaluation using the same bytecode format as is used
1469 for tracepoint actions.
1471 * The disassemble command now supports: an optional /r modifier, print the
1472 raw instructions in hex as well as in symbolic form, and an optional /m
1473 modifier to print mixed source+assembly.
1475 * Process record and replay
1477 In a architecture environment that supports ``process record and
1478 replay'', ``process record and replay'' target can record a log of
1479 the process execution, and replay it with both forward and reverse
1482 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1483 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1484 set execution-direction {forward|reverse}, for targets that support
1487 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1488 feature is available with a native GDB running on kernel version
1491 * GDB now has support for multi-byte and wide character sets on the
1492 target. Strings whose character type is wchar_t, char16_t, or
1493 char32_t are now correctly printed. GDB supports wide- and unicode-
1494 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1495 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1496 `printf'. This feature requires iconv to work properly; if your
1497 system does not have a working iconv, GDB can use GNU libiconv. See
1498 the installation instructions for more information.
1500 * GDB now supports automatic retrieval of shared library files from
1501 remote targets. To use this feature, specify a system root that begins
1502 with the `remote:' prefix, either via the `set sysroot' command or via
1503 the `--with-sysroot' configure-time option.
1505 * "info sharedlibrary" now takes an optional regex of libraries to show,
1506 and it now reports if a shared library has no debugging information.
1508 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1509 now complete on file names.
1511 * When completing in expressions, gdb will attempt to limit
1512 completions to allowable structure or union fields, where appropriate.
1513 For instance, consider:
1515 # struct example { int f1; double f2; };
1516 # struct example variable;
1519 If the user types TAB at the end of this command line, the available
1520 completions will be "f1" and "f2".
1522 * Inlined functions are now supported. They show up in backtraces, and
1523 the "step", "next", and "finish" commands handle them automatically.
1525 * GDB now supports the token-splicing (##) and stringification (#)
1526 operators when expanding macros. It also supports variable-arity
1529 * GDB now supports inspecting extra signal information, exported by
1530 the new $_siginfo convenience variable. The feature is currently
1531 implemented on linux ARM, i386 and amd64.
1533 * GDB can now display the VFP floating point registers and NEON vector
1534 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1535 can provide these registers (requires Linux 2.6.30 or later). Remote
1536 and simulator targets may also provide them.
1538 * New remote packets
1541 Search memory for a sequence of bytes.
1544 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1545 operation over reliable transport links. Use of this packet is
1546 controlled by the `set remote noack-packet' command.
1549 Kill the process with the specified process ID. Use this in preference
1550 to `k' when multiprocess protocol extensions are supported.
1553 Obtains additional operating system information
1557 Read or write additional signal information.
1559 * Removed remote protocol undocumented extension
1561 An undocumented extension to the remote protocol's `S' stop reply
1562 packet that permited the stub to pass a process id was removed.
1563 Remote servers should use the `T' stop reply packet instead.
1565 * GDB now supports multiple function calling conventions according to the
1566 DWARF-2 DW_AT_calling_convention function attribute.
1568 * The SH target utilizes the aforementioned change to distinguish between gcc
1569 and Renesas calling convention. It also adds the new CLI commands
1570 `set/show sh calling-convention'.
1572 * GDB can now read compressed debug sections, as produced by GNU gold
1573 with the --compress-debug-sections=zlib flag.
1575 * 64-bit core files are now supported on AIX.
1577 * Thread switching is now supported on Tru64.
1579 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1580 which will be allocated using malloc later in program execution.
1582 * The qXfer:libraries:read remote procotol packet now allows passing a
1583 list of section offsets.
1585 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1586 conditions handling signals delivered during attach or thread creation
1587 have also been fixed.
1589 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1590 From the user's standpoint, all unqualified instances of True and False
1591 are treated as the standard definitions, regardless of context.
1593 * GDB now parses C++ symbol and type names more flexibly. For
1596 template<typename T> class C { };
1599 GDB will now correctly handle all of:
1601 ptype C<char const *>
1602 ptype C<char const*>
1603 ptype C<const char *>
1604 ptype C<const char*>
1606 * New features in the GDB remote stub, gdbserver
1608 - The "--wrapper" command-line argument tells gdbserver to use a
1609 wrapper program to launch programs for debugging.
1611 - On PowerPC and S/390 targets, it is now possible to use a single
1612 gdbserver executable to debug both 32-bit and 64-bit programs.
1613 (This requires gdbserver itself to be built as a 64-bit executable.)
1615 - gdbserver uses the new noack protocol mode for TCP connections to
1616 reduce communications latency, if also supported and enabled in GDB.
1618 - Support for the sparc64-linux-gnu target is now included in
1621 - The amd64-linux build of gdbserver now supports debugging both
1622 32-bit and 64-bit programs.
1624 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1625 now support hardware watchpoints, and will use them automatically
1630 GDB now has support for scripting using Python. Whether this is
1631 available is determined at configure time.
1633 New GDB commands can now be written in Python.
1635 * Ada tasking support
1637 Ada tasks can now be inspected in GDB. The following commands have
1641 Print the list of Ada tasks.
1643 Print detailed information about task number N.
1645 Print the task number of the current task.
1647 Switch the context of debugging to task number N.
1649 * Support for user-defined prefixed commands. The "define" command can
1650 add new commands to existing prefixes, e.g. "target".
1652 * Multi-inferior, multi-process debugging.
1654 GDB now has generalized support for multi-inferior debugging. See
1655 "Debugging Multiple Inferiors" in the manual for more information.
1656 Although availability still depends on target support, the command
1657 set is more uniform now. The GNU/Linux specific multi-forks support
1658 has been migrated to this new framework. This implied some user
1659 visible changes; see "New commands" and also "Removed commands"
1662 * Target descriptions can now describe the target OS ABI. See the
1663 "Target Description Format" section in the user manual for more
1666 * Target descriptions can now describe "compatible" architectures
1667 to indicate that the target can execute applications for a different
1668 architecture in addition to those for the main target architecture.
1669 See the "Target Description Format" section in the user manual for
1672 * Multi-architecture debugging.
1674 GDB now includes general supports for debugging applications on
1675 hybrid systems that use more than one single processor architecture
1676 at the same time. Each such hybrid architecture still requires
1677 specific support to be added. The only hybrid architecture supported
1678 in this version of GDB is the Cell Broadband Engine.
1680 * GDB now supports integrated debugging of Cell/B.E. applications that
1681 use both the PPU and SPU architectures. To enable support for hybrid
1682 Cell/B.E. debugging, you need to configure GDB to support both the
1683 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1684 --enable-targets configure option.
1686 * Non-stop mode debugging.
1688 For some targets, GDB now supports an optional mode of operation in
1689 which you can examine stopped threads while other threads continue
1690 to execute freely. This is referred to as non-stop mode, with the
1691 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1692 section in the user manual for more information.
1694 To be able to support remote non-stop debugging, a remote stub needs
1695 to implement the non-stop mode remote protocol extensions, as
1696 described in the "Remote Non-Stop" section of the user manual. The
1697 GDB remote stub, gdbserver, has been adjusted to support these
1698 extensions on linux targets.
1700 * New commands (for set/show, see "New options" below)
1702 catch syscall [NAME(S) | NUMBER(S)]
1703 Catch system calls. Arguments, which should be names of system
1704 calls or their numbers, mean catch only those syscalls. Without
1705 arguments, every syscall will be caught. When the inferior issues
1706 any of the specified syscalls, GDB will stop and announce the system
1707 call, both when it is called and when its call returns. This
1708 feature is currently available with a native GDB running on the
1709 Linux Kernel, under the following architectures: x86, x86_64,
1710 PowerPC and PowerPC64.
1712 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1714 Search memory for a sequence of bytes.
1716 maint set python print-stack
1717 maint show python print-stack
1718 Show a stack trace when an error is encountered in a Python script.
1721 Invoke CODE by passing it to the Python interpreter.
1726 These allow macros to be defined, undefined, and listed
1730 Show operating system information about processes.
1733 List the inferiors currently under GDB's control.
1736 Switch focus to inferior number NUM.
1739 Detach from inferior number NUM.
1742 Kill inferior number NUM.
1746 set spu stop-on-load
1747 show spu stop-on-load
1748 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1750 set spu auto-flush-cache
1751 show spu auto-flush-cache
1752 Control whether to automatically flush the software-managed cache
1753 during Cell/B.E. debugging.
1755 set sh calling-convention
1756 show sh calling-convention
1757 Control the calling convention used when calling SH target functions.
1760 show debug timestamp
1761 Control display of timestamps with GDB debugging output.
1763 set disassemble-next-line
1764 show disassemble-next-line
1765 Control display of disassembled source lines or instructions when
1768 set remote noack-packet
1769 show remote noack-packet
1770 Set/show the use of remote protocol QStartNoAckMode packet. See above
1771 under "New remote packets."
1773 set remote query-attached-packet
1774 show remote query-attached-packet
1775 Control use of remote protocol `qAttached' (query-attached) packet.
1777 set remote read-siginfo-object
1778 show remote read-siginfo-object
1779 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1782 set remote write-siginfo-object
1783 show remote write-siginfo-object
1784 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1787 set remote reverse-continue
1788 show remote reverse-continue
1789 Control use of remote protocol 'bc' (reverse-continue) packet.
1791 set remote reverse-step
1792 show remote reverse-step
1793 Control use of remote protocol 'bs' (reverse-step) packet.
1795 set displaced-stepping
1796 show displaced-stepping
1797 Control displaced stepping mode. Displaced stepping is a way to
1798 single-step over breakpoints without removing them from the debuggee.
1799 Also known as "out-of-line single-stepping".
1802 show debug displaced
1803 Control display of debugging info for displaced stepping.
1805 maint set internal-error
1806 maint show internal-error
1807 Control what GDB does when an internal error is detected.
1809 maint set internal-warning
1810 maint show internal-warning
1811 Control what GDB does when an internal warning is detected.
1816 Use a wrapper program to launch programs for debugging.
1818 set multiple-symbols (all|ask|cancel)
1819 show multiple-symbols
1820 The value of this variable can be changed to adjust the debugger behavior
1821 when an expression or a breakpoint location contains an ambiguous symbol
1822 name (an overloaded function name, for instance).
1824 set breakpoint always-inserted
1825 show breakpoint always-inserted
1826 Keep breakpoints always inserted in the target, as opposed to inserting
1827 them when resuming the target, and removing them when the target stops.
1828 This option can improve debugger performance on slow remote targets.
1830 set arm fallback-mode (arm|thumb|auto)
1831 show arm fallback-mode
1832 set arm force-mode (arm|thumb|auto)
1834 These commands control how ARM GDB determines whether instructions
1835 are ARM or Thumb. The default for both settings is auto, which uses
1836 the current CPSR value for instructions without symbols; previous
1837 versions of GDB behaved as if "set arm fallback-mode arm".
1839 set disable-randomization
1840 show disable-randomization
1841 Standalone programs run with the virtual address space randomization enabled
1842 by default on some platforms. This option keeps the addresses stable across
1843 multiple debugging sessions.
1847 Control whether other threads are stopped or not when some thread hits
1852 Requests that asynchronous execution is enabled in the target, if available.
1853 In this case, it's possible to resume target in the background, and interact
1854 with GDB while the target is running. "show target-async" displays the
1855 current state of asynchronous execution of the target.
1857 set target-wide-charset
1858 show target-wide-charset
1859 The target-wide-charset is the name of the character set that GDB
1860 uses when printing characters whose type is wchar_t.
1862 set tcp auto-retry (on|off)
1864 set tcp connect-timeout
1865 show tcp connect-timeout
1866 These commands allow GDB to retry failed TCP connections to a remote stub
1867 with a specified timeout period; this is useful if the stub is launched
1868 in parallel with GDB but may not be ready to accept connections immediately.
1870 set libthread-db-search-path
1871 show libthread-db-search-path
1872 Control list of directories which GDB will search for appropriate
1875 set schedule-multiple (on|off)
1876 show schedule-multiple
1877 Allow GDB to resume all threads of all processes or only threads of
1878 the current process.
1882 Use more aggressive caching for accesses to the stack. This improves
1883 performance of remote debugging (particularly backtraces) without
1884 affecting correctness.
1886 set interactive-mode (on|off|auto)
1887 show interactive-mode
1888 Control whether GDB runs in interactive mode (on) or not (off).
1889 When in interactive mode, GDB waits for the user to answer all
1890 queries. Otherwise, GDB does not wait and assumes the default
1891 answer. When set to auto (the default), GDB determines which
1892 mode to use based on the stdin settings.
1897 For program forks, this is replaced by the new more generic `info
1898 inferiors' command. To list checkpoints, you can still use the
1899 `info checkpoints' command, which was an alias for the `info forks'
1903 Replaced by the new `inferior' command. To switch between
1904 checkpoints, you can still use the `restart' command, which was an
1905 alias for the `fork' command.
1908 This is removed, since some targets don't have a notion of
1909 processes. To switch between processes, you can still use the
1910 `inferior' command using GDB's own inferior number.
1913 For program forks, this is replaced by the new more generic `kill
1914 inferior' command. To delete a checkpoint, you can still use the
1915 `delete checkpoint' command, which was an alias for the `delete
1919 For program forks, this is replaced by the new more generic `detach
1920 inferior' command. To detach a checkpoint, you can still use the
1921 `detach checkpoint' command, which was an alias for the `detach
1924 * New native configurations
1926 x86/x86_64 Darwin i[34567]86-*-darwin*
1928 x86_64 MinGW x86_64-*-mingw*
1932 Lattice Mico32 lm32-*
1933 x86 DICOS i[34567]86-*-dicos*
1934 x86_64 DICOS x86_64-*-dicos*
1937 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1938 (mingw32ce) debugging.
1944 These commands were actually not implemented on any target.
1946 *** Changes in GDB 6.8
1948 * New native configurations
1950 NetBSD/hppa hppa*-*netbsd*
1951 Xtensa GNU/Linux xtensa*-*-linux*
1955 NetBSD/hppa hppa*-*-netbsd*
1956 Xtensa GNU/Lunux xtensa*-*-linux*
1958 * Change in command line behavior -- corefiles vs. process ids.
1960 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1961 attaching to process NUMBER fails, GDB no longer attempts to open a
1962 core file named NUMBER. Attaching to a program using the -c option
1963 is no longer supported. Instead, use the '-p' or '--pid' options.
1965 * GDB can now be built as a native debugger for debugging Windows x86
1966 (mingw32) Portable Executable (PE) programs.
1968 * Pending breakpoints no longer change their number when their address
1971 * GDB now supports breakpoints with multiple locations,
1972 including breakpoints on C++ constructors, inside C++ templates,
1973 and in inlined functions.
1975 * GDB's ability to debug optimized code has been improved. GDB more
1976 accurately identifies function bodies and lexical blocks that occupy
1977 more than one contiguous range of addresses.
1979 * Target descriptions can now describe registers for PowerPC.
1981 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1982 registers on PowerPC targets.
1984 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1985 targets even when the libthread_db library is not available.
1987 * The GDB remote stub, gdbserver, now supports the new file transfer
1988 commands (remote put, remote get, and remote delete).
1990 * The GDB remote stub, gdbserver, now supports run and attach in
1991 extended-remote mode.
1993 * hppa*64*-*-hpux11* target broken
1994 The debugger is unable to start a program and fails with the following
1995 error: "Error trying to get information about dynamic linker".
1996 The gdb-6.7 release is also affected.
1998 * GDB now supports the --enable-targets= configure option to allow
1999 building a single GDB executable that supports multiple remote
2000 target architectures.
2002 * GDB now supports debugging C and C++ programs which use the
2003 Decimal Floating Point extension. In addition, the PowerPC target
2004 now has a set of pseudo-registers to inspect decimal float values
2005 stored in two consecutive float registers.
2007 * The -break-insert MI command can optionally create pending
2010 * Improved support for debugging Ada
2011 Many improvements to the Ada language support have been made. These
2013 - Better support for Ada2005 interface types
2014 - Improved handling of arrays and slices in general
2015 - Better support for Taft-amendment types
2016 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2018 - Improved command completion in Ada
2021 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2026 set print frame-arguments (all|scalars|none)
2027 show print frame-arguments
2028 The value of this variable can be changed to control which argument
2029 values should be printed by the debugger when displaying a frame.
2034 Transfer files to and from a remote target, and delete remote files.
2041 Transfer files to and from a remote target, and delete remote files.
2043 * New remote packets
2050 Open, close, read, write, and delete files on the remote system.
2053 Attach to an existing process on the remote system, in extended-remote
2057 Run a new process on the remote system, in extended-remote mode.
2059 *** Changes in GDB 6.7
2061 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2062 bfd, libiberty and opcodes, as revealed by static analysis donated by
2063 Coverity, Inc. (http://scan.coverity.com).
2065 * When looking up multiply-defined global symbols, GDB will now prefer the
2066 symbol definition in the current shared library if it was built using the
2067 -Bsymbolic linker option.
2069 * When the Text User Interface (TUI) is not configured, GDB will now
2070 recognize the -tui command-line option and print a message that the TUI
2073 * The GDB remote stub, gdbserver, now has lower overhead for high
2074 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2076 * GDB for MIPS targets now autodetects whether a remote target provides
2077 32-bit or 64-bit register values.
2079 * Support for C++ member pointers has been improved.
2081 * GDB now understands XML target descriptions, which specify the
2082 target's overall architecture. GDB can read a description from
2083 a local file or over the remote serial protocol.
2085 * Vectors of single-byte data use a new integer type which is not
2086 automatically displayed as character or string data.
2088 * The /s format now works with the print command. It displays
2089 arrays of single-byte integers and pointers to single-byte integers
2092 * Target descriptions can now describe target-specific registers,
2093 for architectures which have implemented the support (currently
2094 only ARM, M68K, and MIPS).
2096 * GDB and the GDB remote stub, gdbserver, now support the XScale
2099 * The GDB remote stub, gdbserver, has been updated to support
2100 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2101 has been rewritten to use the standard GDB remote protocol.
2103 * GDB can now step into C++ functions which are called through thunks.
2105 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2107 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2108 layout. It also supports a TextSeg= and DataSeg= response when only
2109 segment base addresses (rather than offsets) are available.
2111 * The /i format now outputs any trailing branch delay slot instructions
2112 immediately following the last instruction within the count specified.
2114 * The GDB remote protocol "T" stop reply packet now supports a
2115 "library" response. Combined with the new "qXfer:libraries:read"
2116 packet, this response allows GDB to debug shared libraries on targets
2117 where the operating system manages the list of loaded libraries (e.g.
2118 Windows and SymbianOS).
2120 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2121 (DLLs) on Windows and Windows CE targets.
2123 * GDB now supports a faster verification that a .debug file matches its binary
2124 according to its build-id signature, if the signature is present.
2130 Enable or disable hardware flow control (RTS/CTS) on the serial port
2131 when debugging using remote targets.
2133 set mem inaccessible-by-default
2134 show mem inaccessible-by-default
2135 If the target supplies a memory map, for instance via the remote
2136 protocol's "qXfer:memory-map:read" packet, setting this variable
2137 prevents GDB from accessing memory outside the memory map. This
2138 is useful for targets with memory mapped registers or which react
2139 badly to accesses of unmapped address space.
2141 set breakpoint auto-hw
2142 show breakpoint auto-hw
2143 If the target supplies a memory map, for instance via the remote
2144 protocol's "qXfer:memory-map:read" packet, setting this variable
2145 lets GDB use hardware breakpoints automatically for memory regions
2146 where it can not use software breakpoints. This covers both the
2147 "break" command and internal breakpoints used for other commands
2148 including "next" and "finish".
2151 catch exception unhandled
2152 Stop the program execution when Ada exceptions are raised.
2155 Stop the program execution when an Ada assertion failed.
2159 Set an alternate system root for target files. This is a more
2160 general version of "set solib-absolute-prefix", which is now
2161 an alias to "set sysroot".
2164 Provide extended SPU facility status information. This set of
2165 commands is available only when debugging the Cell/B.E. SPU
2168 * New native configurations
2170 OpenBSD/sh sh*-*openbsd*
2173 unset tdesc filename
2175 Use the specified local file as an XML target description, and do
2176 not query the target for its built-in description.
2180 OpenBSD/sh sh*-*-openbsd*
2181 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2182 Toshiba Media Processor mep-elf
2184 * New remote packets
2187 Ignore the specified signals; pass them directly to the debugged program
2188 without stopping other threads or reporting them to GDB.
2190 qXfer:features:read:
2191 Read an XML target description from the target, which describes its
2196 Read or write contents of an spufs file on the target system. These
2197 packets are available only on the Cell/B.E. SPU architecture.
2199 qXfer:libraries:read:
2200 Report the loaded shared libraries. Combined with new "T" packet
2201 response, this packet allows GDB to debug shared libraries on
2202 targets where the operating system manages the list of loaded
2203 libraries (e.g. Windows and SymbianOS).
2207 Support for these obsolete configurations has been removed.
2215 i[34567]86-*-lynxos*
2216 i[34567]86-*-netware*
2217 i[34567]86-*-sco3.2v5*
2218 i[34567]86-*-sco3.2v4*
2220 i[34567]86-*-sysv4.2*
2223 i[34567]86-*-unixware2*
2224 i[34567]86-*-unixware*
2233 * Other removed features
2240 Various m68k-only ROM monitors.
2247 Various Renesas ROM monitors and debugging interfaces for SH and
2252 Support for a Macraigor serial interface to on-chip debugging.
2253 GDB does not directly support the newer parallel or USB
2258 A debug information format. The predecessor to DWARF 2 and
2259 DWARF 3, which are still supported.
2261 Support for the HP aCC compiler on HP-UX/PA-RISC
2263 SOM-encapsulated symbolic debugging information, automatic
2264 invocation of pxdb, and the aCC custom C++ ABI. This does not
2265 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2266 with aCC can still be debugged on an assembly level.
2268 MIPS ".pdr" sections
2270 A MIPS-specific format used to describe stack frame layout
2271 in debugging information.
2275 GDB could work with an older version of Guile to debug
2276 the interpreter and Scheme programs running in it.
2278 set mips stack-arg-size
2279 set mips saved-gpreg-size
2281 Use "set mips abi" to control parameter passing for MIPS.
2283 *** Changes in GDB 6.6
2288 Cell Broadband Engine SPU spu-elf
2290 * GDB can now be configured as a cross-debugger targeting native Windows
2291 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2292 running on a Windows system over TCP/IP to debug Windows programs.
2294 * The GDB remote stub, gdbserver, has been updated to support Windows and
2295 Cygwin debugging. Both single-threaded and multi-threaded programs are
2298 * The "set trust-readonly-sections" command works again. This command was
2299 broken in GDB 6.3, 6.4, and 6.5.
2301 * The "load" command now supports writing to flash memory, if the remote
2302 stub provides the required support.
2304 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2305 longer requires symbolic debug information (e.g. DWARF-2).
2310 unset substitute-path
2311 show substitute-path
2312 Manage a list of substitution rules that GDB uses to rewrite the name
2313 of the directories where the sources are located. This can be useful
2314 for instance when the sources were moved to a different location
2315 between compilation and debugging.
2319 Print each CLI command as it is executed. Each command is prefixed with
2320 a number of `+' symbols representing the nesting depth.
2321 The source command now has a `-v' option to enable the same feature.
2325 The ARM Demon monitor support (RDP protocol, "target rdp").
2327 Kernel Object Display, an embedded debugging feature which only worked with
2328 an obsolete version of Cisco IOS.
2330 The 'set download-write-size' and 'show download-write-size' commands.
2332 * New remote packets
2335 Tell a stub about GDB client features, and request remote target features.
2336 The first feature implemented is PacketSize, which allows the target to
2337 specify the size of packets it can handle - to minimize the number of
2338 packets required and improve performance when connected to a remote
2342 Fetch an OS auxilliary vector from the remote stub. This packet is a
2343 more efficient replacement for qPart:auxv:read.
2345 qXfer:memory-map:read:
2346 Fetch a memory map from the remote stub, including information about
2347 RAM, ROM, and flash memory devices.
2352 Erase and program a flash memory device.
2354 * Removed remote packets
2357 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2358 used it, and only gdbserver implemented it.
2360 *** Changes in GDB 6.5
2364 Renesas M32C/M16C m32c-elf
2366 Morpho Technologies ms1 ms1-elf
2370 init-if-undefined Initialize a convenience variable, but
2371 only if it doesn't already have a value.
2373 The following commands are presently only implemented for native GNU/Linux:
2375 checkpoint Save a snapshot of the program state.
2377 restart <n> Return the program state to a
2378 previously saved state.
2380 info checkpoints List currently saved checkpoints.
2382 delete-checkpoint <n> Delete a previously saved checkpoint.
2384 set|show detach-on-fork Tell gdb whether to detach from a newly
2385 forked process, or to keep debugging it.
2387 info forks List forks of the user program that
2388 are available to be debugged.
2390 fork <n> Switch to debugging one of several
2391 forks of the user program that are
2392 available to be debugged.
2394 delete-fork <n> Delete a fork from the list of forks
2395 that are available to be debugged (and
2396 kill the forked process).
2398 detach-fork <n> Delete a fork from the list of forks
2399 that are available to be debugged (and
2400 allow the process to continue).
2404 Morpho Technologies ms2 ms1-elf
2406 * Improved Windows host support
2408 GDB now builds as a cross debugger hosted on i686-mingw32, including
2409 native console support, and remote communications using either
2410 network sockets or serial ports.
2412 * Improved Modula-2 language support
2414 GDB can now print most types in the Modula-2 syntax. This includes:
2415 basic types, set types, record types, enumerated types, range types,
2416 pointer types and ARRAY types. Procedure var parameters are correctly
2417 printed and hexadecimal addresses and character constants are also
2418 written in the Modula-2 syntax. Best results can be obtained by using
2419 GNU Modula-2 together with the -gdwarf-2 command line option.
2423 The ARM rdi-share module.
2425 The Netware NLM debug server.
2427 *** Changes in GDB 6.4
2429 * New native configurations
2431 OpenBSD/arm arm*-*-openbsd*
2432 OpenBSD/mips64 mips64-*-openbsd*
2436 Morpho Technologies ms1 ms1-elf
2438 * New command line options
2440 --batch-silent As for --batch, but totally silent.
2441 --return-child-result The debugger will exist with the same value
2442 the child (debugged) program exited with.
2443 --eval-command COMMAND, -ex COMMAND
2444 Execute a single GDB CLI command. This may be
2445 specified multiple times and in conjunction
2446 with the --command (-x) option.
2448 * Deprecated commands removed
2450 The following commands, that were deprecated in 2000, have been
2454 set|show arm disassembly-flavor set|show arm disassembler
2455 othernames set arm disassembler
2456 set|show remotedebug set|show debug remote
2457 set|show archdebug set|show debug arch
2458 set|show eventdebug set|show debug event
2461 * New BSD user-level threads support
2463 It is now possible to debug programs using the user-level threads
2464 library on OpenBSD and FreeBSD. Currently supported (target)
2467 FreeBSD/amd64 x86_64-*-freebsd*
2468 FreeBSD/i386 i386-*-freebsd*
2469 OpenBSD/i386 i386-*-openbsd*
2471 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2472 are not yet supported.
2474 * New support for Matsushita MN10300 w/sim added
2475 (Work in progress). mn10300-elf.
2477 * REMOVED configurations and files
2479 VxWorks and the XDR protocol *-*-vxworks
2480 Motorola MCORE mcore-*-*
2481 National Semiconductor NS32000 ns32k-*-*
2483 * New "set print array-indexes" command
2485 After turning this setting "on", GDB prints the index of each element
2486 when displaying arrays. The default is "off" to preserve the previous
2489 * VAX floating point support
2491 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2493 * User-defined command support
2495 In addition to using $arg0..$arg9 for argument passing, it is now possible
2496 to use $argc to determine now many arguments have been passed. See the
2497 section on user-defined commands in the user manual for more information.
2499 *** Changes in GDB 6.3:
2501 * New command line option
2503 GDB now accepts -l followed by a number to set the timeout for remote
2506 * GDB works with GCC -feliminate-dwarf2-dups
2508 GDB now supports a more compact representation of DWARF-2 debug
2509 information using DW_FORM_ref_addr references. These are produced
2510 by GCC with the option -feliminate-dwarf2-dups and also by some
2511 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2512 to use -feliminate-dwarf2-dups.
2514 * Internationalization
2516 When supported by the host system, GDB will be built with
2517 internationalization (libintl). The task of marking up the sources is
2518 continued, we're looking forward to our first translation.
2522 Initial support for debugging programs compiled with the GNAT
2523 implementation of the Ada programming language has been integrated
2524 into GDB. In this release, support is limited to expression evaluation.
2526 * New native configurations
2528 GNU/Linux/m32r m32r-*-linux-gnu
2532 GDB's remote protocol now includes support for the 'p' packet. This
2533 packet is used to fetch individual registers from a remote inferior.
2535 * END-OF-LIFE registers[] compatibility module
2537 GDB's internal register infrastructure has been completely rewritten.
2538 The new infrastructure making possible the implementation of key new
2539 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2542 GDB 6.3 will be the last release to include the the registers[]
2543 compatibility module that allowed out-of-date configurations to
2544 continue to work. This change directly impacts the following
2554 powerpc bdm protocol
2556 Unless there is activity to revive these configurations, they will be
2557 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2559 * OBSOLETE configurations and files
2561 Configurations that have been declared obsolete in this release have
2562 been commented out. Unless there is activity to revive these
2563 configurations, the next release of GDB will have their sources
2564 permanently REMOVED.
2573 *** Changes in GDB 6.2.1:
2575 * MIPS `break main; run' gave an heuristic-fence-post warning
2577 When attempting to run even a simple program, a warning about
2578 heuristic-fence-post being hit would be reported. This problem has
2581 * MIPS IRIX 'long double' crashed GDB
2583 When examining a long double variable, GDB would get a segmentation
2584 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2585 IRIX long double values).
2589 A bug in the VAX stack code was causing problems with the "next"
2590 command. This problem has been fixed.
2592 *** Changes in GDB 6.2:
2594 * Fix for ``many threads''
2596 On GNU/Linux systems that use the NPTL threads library, a program
2597 rapidly creating and deleting threads would confuse GDB leading to the
2600 ptrace: No such process.
2601 thread_db_get_info: cannot get thread info: generic error
2603 This problem has been fixed.
2605 * "-async" and "-noasync" options removed.
2607 Support for the broken "-noasync" option has been removed (it caused
2610 * New ``start'' command.
2612 This command runs the program until the begining of the main procedure.
2614 * New BSD Kernel Data Access Library (libkvm) interface
2616 Using ``target kvm'' it is now possible to debug kernel core dumps and
2617 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2618 platforms. Currently supported (native-only) configurations are:
2620 FreeBSD/amd64 x86_64-*-freebsd*
2621 FreeBSD/i386 i?86-*-freebsd*
2622 NetBSD/i386 i?86-*-netbsd*
2623 NetBSD/m68k m68*-*-netbsd*
2624 NetBSD/sparc sparc-*-netbsd*
2625 OpenBSD/amd64 x86_64-*-openbsd*
2626 OpenBSD/i386 i?86-*-openbsd*
2627 OpenBSD/m68k m68*-openbsd*
2628 OpenBSD/sparc sparc-*-openbsd*
2630 * Signal trampoline code overhauled
2632 Many generic problems with GDB's signal handling code have been fixed.
2633 These include: backtraces through non-contiguous stacks; recognition
2634 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2635 call; backtrace through a signal trampoline; step into and out of
2636 signal handlers; and single-stepping in the signal trampoline.
2638 Please note that kernel bugs are a limiting factor here. These
2639 features have been shown to work on an s390 GNU/Linux system that
2640 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2642 * Cygwin support for DWARF 2 added.
2644 * New native configurations
2646 GNU/Linux/hppa hppa*-*-linux*
2647 OpenBSD/hppa hppa*-*-openbsd*
2648 OpenBSD/m68k m68*-*-openbsd*
2649 OpenBSD/m88k m88*-*-openbsd*
2650 OpenBSD/powerpc powerpc-*-openbsd*
2651 NetBSD/vax vax-*-netbsd*
2652 OpenBSD/vax vax-*-openbsd*
2654 * END-OF-LIFE frame compatibility module
2656 GDB's internal frame infrastructure has been completely rewritten.
2657 The new infrastructure making it possible to support key new features
2658 including DWARF 2 Call Frame Information. To aid in the task of
2659 migrating old configurations to this new infrastructure, a
2660 compatibility module, that allowed old configurations to continue to
2661 work, was also included.
2663 GDB 6.2 will be the last release to include this frame compatibility
2664 module. This change directly impacts the following configurations:
2674 Unless there is activity to revive these configurations, they will be
2675 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2677 * REMOVED configurations and files
2679 Sun 3, running SunOS 3 m68*-*-sunos3*
2680 Sun 3, running SunOS 4 m68*-*-sunos4*
2681 Sun 2, running SunOS 3 m68000-*-sunos3*
2682 Sun 2, running SunOS 4 m68000-*-sunos4*
2683 Motorola 680x0 running LynxOS m68*-*-lynxos*
2684 AT&T 3b1/Unix pc m68*-att-*
2685 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2686 decstation mips-dec-* mips-little-*
2687 riscos mips-*-riscos* mips-*-sysv*
2688 sonymips mips-sony-*
2689 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2691 *** Changes in GDB 6.1.1:
2693 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2695 The TUI (Text-mode User Interface) is now built as part of a default
2696 GDB configuration. It is enabled by either selecting the TUI with the
2697 command line option "-i=tui" or by running the separate "gdbtui"
2698 program. For more information on the TUI, see the manual "Debugging
2701 * Pending breakpoint support (also included in GDB 6.1)
2703 Support has been added to allow you to specify breakpoints in shared
2704 libraries that have not yet been loaded. If a breakpoint location
2705 cannot be found, and the "breakpoint pending" option is set to auto,
2706 GDB queries you if you wish to make the breakpoint pending on a future
2707 shared-library load. If and when GDB resolves the breakpoint symbol,
2708 the pending breakpoint is removed as one or more regular breakpoints
2711 Pending breakpoints are very useful for GCJ Java debugging.
2713 * Fixed ISO-C build problems
2715 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2716 non ISO-C code that stopped them being built using a more strict ISO-C
2717 compiler (e.g., IBM's C compiler).
2719 * Fixed build problem on IRIX 5
2721 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2722 wasn't able to compile compile on an IRIX 5 system.
2724 * Added execute permission to gdb/gdbserver/configure
2726 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2727 permission. This bug would cause configure to fail on a number of
2728 systems (Solaris, IRIX). Ref: server/519.
2730 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2732 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2733 has been updated to use constant array sizes.
2735 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2737 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2738 its generated DWARF Call Frame Info. This encoding was causing GDB to
2739 panic, that panic has been fixed. Ref: gdb/1628.
2741 * Fixed a problem when examining parameters in shared library code.
2743 When examining parameters in optimized shared library code generated
2744 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2745 not available''. GDB now correctly displays the variable's value.
2747 *** Changes in GDB 6.1:
2749 * Removed --with-mmalloc
2751 Support for the mmalloc memory manager has been removed, as it
2752 conflicted with the internal gdb byte cache.
2754 * Changes in AMD64 configurations
2756 The AMD64 target now includes the %cs and %ss registers. As a result
2757 the AMD64 remote protocol has changed; this affects the floating-point
2758 and SSE registers. If you rely on those registers for your debugging,
2759 you should upgrade gdbserver on the remote side.
2761 * Revised SPARC target
2763 The SPARC target has been completely revised, incorporating the
2764 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2765 support for LynxOS and SunOS 4 has been dropped. Calling functions
2766 from within GDB on operating systems with a non-executable stack
2767 (Solaris, OpenBSD) now works.
2771 GDB has a new C++ demangler which does a better job on the mangled
2772 names generated by current versions of g++. It also runs faster, so
2773 with this and other changes gdb should now start faster on large C++
2776 * DWARF 2 Location Expressions
2778 GDB support for location expressions has been extended to support function
2779 arguments and frame bases. Older versions of GDB could crash when they
2782 * C++ nested types and namespaces
2784 GDB's support for nested types and namespaces in C++ has been
2785 improved, especially if you use the DWARF 2 debugging format. (This
2786 is the default for recent versions of GCC on most platforms.)
2787 Specifically, if you have a class "Inner" defined within a class or
2788 namespace "Outer", then GDB realizes that the class's name is
2789 "Outer::Inner", not simply "Inner". This should greatly reduce the
2790 frequency of complaints about not finding RTTI symbols. In addition,
2791 if you are stopped at inside of a function defined within a namespace,
2792 GDB modifies its name lookup accordingly.
2794 * New native configurations
2796 NetBSD/amd64 x86_64-*-netbsd*
2797 OpenBSD/amd64 x86_64-*-openbsd*
2798 OpenBSD/alpha alpha*-*-openbsd*
2799 OpenBSD/sparc sparc-*-openbsd*
2800 OpenBSD/sparc64 sparc64-*-openbsd*
2802 * New debugging protocols
2804 M32R with SDI protocol m32r-*-elf*
2806 * "set prompt-escape-char" command deleted.
2808 The command "set prompt-escape-char" has been deleted. This command,
2809 and its very obscure effet on GDB's prompt, was never documented,
2810 tested, nor mentioned in the NEWS file.
2812 * OBSOLETE configurations and files
2814 Configurations that have been declared obsolete in this release have
2815 been commented out. Unless there is activity to revive these
2816 configurations, the next release of GDB will have their sources
2817 permanently REMOVED.
2819 Sun 3, running SunOS 3 m68*-*-sunos3*
2820 Sun 3, running SunOS 4 m68*-*-sunos4*
2821 Sun 2, running SunOS 3 m68000-*-sunos3*
2822 Sun 2, running SunOS 4 m68000-*-sunos4*
2823 Motorola 680x0 running LynxOS m68*-*-lynxos*
2824 AT&T 3b1/Unix pc m68*-att-*
2825 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2826 decstation mips-dec-* mips-little-*
2827 riscos mips-*-riscos* mips-*-sysv*
2828 sonymips mips-sony-*
2829 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2831 * REMOVED configurations and files
2833 SGI Irix-4.x mips-sgi-irix4 or iris4
2834 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2835 Z8000 simulator z8k-zilog-none or z8ksim
2836 Matsushita MN10200 w/simulator mn10200-*-*
2837 H8/500 simulator h8500-hitachi-hms or h8500hms
2838 HP/PA running BSD hppa*-*-bsd*
2839 HP/PA running OSF/1 hppa*-*-osf*
2840 HP/PA Pro target hppa*-*-pro*
2841 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2842 386BSD i[3456]86-*-bsd*
2843 Sequent family i[3456]86-sequent-sysv4*
2844 i[3456]86-sequent-sysv*
2845 i[3456]86-sequent-bsd*
2846 SPARC running LynxOS sparc-*-lynxos*
2847 SPARC running SunOS 4 sparc-*-sunos4*
2848 Tsqware Sparclet sparclet-*-*
2849 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2851 *** Changes in GDB 6.0:
2855 Support for debugging the Objective-C programming language has been
2856 integrated into GDB.
2858 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2860 DWARF 2's Call Frame Information makes available compiler generated
2861 information that more exactly describes the program's run-time stack.
2862 By using this information, GDB is able to provide more robust stack
2865 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2866 have been updated to use a new backtrace mechanism which includes
2867 DWARF 2 CFI support.
2871 GDB's remote protocol has been extended to include support for hosted
2872 file I/O (where the remote target uses GDB's file system). See GDB's
2873 remote protocol documentation for details.
2875 * All targets using the new architecture framework.
2877 All of GDB's targets have been updated to use the new internal
2878 architecture framework. The way is now open for future GDB releases
2879 to include cross-architecture native debugging support (i386 on amd64,
2882 * GNU/Linux's Thread Local Storage (TLS)
2884 GDB now includes support for for the GNU/Linux implementation of
2885 per-thread variables.
2887 * GNU/Linux's Native POSIX Thread Library (NPTL)
2889 GDB's thread code has been updated to work with either the new
2890 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2892 * Separate debug info.
2894 GDB, in conjunction with BINUTILS, now supports a mechanism for
2895 automatically loading debug information from a separate file. Instead
2896 of shipping full debug and non-debug versions of system libraries,
2897 system integrators can now instead ship just the stripped libraries
2898 and optional debug files.
2900 * DWARF 2 Location Expressions
2902 DWARF 2 Location Expressions allow the compiler to more completely
2903 describe the location of variables (even in optimized code) to the
2906 GDB now includes preliminary support for location expressions (support
2907 for DW_OP_piece is still missing).
2911 A number of long standing bugs that caused GDB to die while starting a
2912 Java application have been fixed. GDB's Java support is now
2913 considered "useable".
2915 * GNU/Linux support for fork, vfork, and exec.
2917 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2918 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2921 * GDB supports logging output to a file
2923 There are two new commands, "set logging" and "show logging", which can be
2924 used to capture GDB's output to a file.
2926 * The meaning of "detach" has changed for gdbserver
2928 The "detach" command will now resume the application, as documented. To
2929 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2932 * d10v, m68hc11 `regs' command deprecated
2934 The `info registers' command has been updated so that it displays the
2935 registers using a format identical to the old `regs' command.
2939 A new command, "maint set profile on/off", has been added. This command can
2940 be used to enable or disable profiling while running GDB, to profile a
2941 session or a set of commands. In addition there is a new configure switch,
2942 "--enable-profiling", which will cause GDB to be compiled with profiling
2943 data, for more informative profiling results.
2945 * Default MI syntax changed to "mi2".
2947 The default MI (machine interface) syntax, enabled by the command line
2948 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2949 "mi1", can be enabled by specifying the option "-i=mi1".
2951 Support for the original "mi0" syntax (included in GDB 5.0) has been
2954 Fix for gdb/192: removed extraneous space when displaying frame level.
2955 Fix for gdb/672: update changelist is now output in mi list format.
2956 Fix for gdb/702: a -var-assign that updates the value now shows up
2957 in a subsequent -var-update.
2959 * New native configurations.
2961 FreeBSD/amd64 x86_64-*-freebsd*
2963 * Multi-arched targets.
2965 HP/PA HPUX11 hppa*-*-hpux*
2966 Renesas M32R/D w/simulator m32r-*-elf*
2968 * OBSOLETE configurations and files
2970 Configurations that have been declared obsolete in this release have
2971 been commented out. Unless there is activity to revive these
2972 configurations, the next release of GDB will have their sources
2973 permanently REMOVED.
2975 Z8000 simulator z8k-zilog-none or z8ksim
2976 Matsushita MN10200 w/simulator mn10200-*-*
2977 H8/500 simulator h8500-hitachi-hms or h8500hms
2978 HP/PA running BSD hppa*-*-bsd*
2979 HP/PA running OSF/1 hppa*-*-osf*
2980 HP/PA Pro target hppa*-*-pro*
2981 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2982 Sequent family i[3456]86-sequent-sysv4*
2983 i[3456]86-sequent-sysv*
2984 i[3456]86-sequent-bsd*
2985 Tsqware Sparclet sparclet-*-*
2986 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2988 * REMOVED configurations and files
2991 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2992 IBM AIX PS/2 i[3456]86-*-aix
2993 i386 running Mach 3.0 i[3456]86-*-mach3*
2994 i386 running Mach i[3456]86-*-mach*
2995 i386 running OSF/1 i[3456]86-*osf1mk*
2996 HP/Apollo 68k Family m68*-apollo*-sysv*,
2998 m68*-hp-bsd*, m68*-hp-hpux*
2999 Argonaut Risc Chip (ARC) arc-*-*
3000 Mitsubishi D30V d30v-*-*
3001 Fujitsu FR30 fr30-*-elf*
3002 OS/9000 i[34]86-*-os9k
3003 I960 with MON960 i960-*-coff
3005 * MIPS $fp behavior changed
3007 The convenience variable $fp, for the MIPS, now consistently returns
3008 the address of the current frame's base. Previously, depending on the
3009 context, $fp could refer to either $sp or the current frame's base
3010 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3011 The GNU Source-Level Debugger''.
3013 *** Changes in GDB 5.3:
3015 * GNU/Linux shared library multi-threaded performance improved.
3017 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3018 `/proc', in preference to `ptrace' for memory reads. This may result
3019 in an improvement in the start-up time of multi-threaded, shared
3020 library applications when run under GDB. One GDB user writes: ``loads
3021 shared libs like mad''.
3023 * ``gdbserver'' now supports multi-threaded applications on some targets
3025 Support for debugging multi-threaded applications which use
3026 the GNU/Linux LinuxThreads package has been added for
3027 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3028 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3030 * GDB now supports C/C++ preprocessor macros.
3032 GDB now expands preprocessor macro invocations in C/C++ expressions,
3033 and provides various commands for showing macro definitions and how
3036 The new command `macro expand EXPRESSION' expands any macro
3037 invocations in expression, and shows the result.
3039 The new command `show macro MACRO-NAME' shows the definition of the
3040 macro named MACRO-NAME, and where it was defined.
3042 Most compilers don't include information about macros in the debugging
3043 information by default. In GCC 3.1, for example, you need to compile
3044 your program with the options `-gdwarf-2 -g3'. If the macro
3045 information is present in the executable, GDB will read it.
3047 * Multi-arched targets.
3049 DEC Alpha (partial) alpha*-*-*
3050 DEC VAX (partial) vax-*-*
3052 National Semiconductor NS32000 (partial) ns32k-*-*
3053 Motorola 68000 (partial) m68k-*-*
3054 Motorola MCORE mcore-*-*
3058 Fujitsu FRV architecture added by Red Hat frv*-*-*
3061 * New native configurations
3063 Alpha NetBSD alpha*-*-netbsd*
3064 SH NetBSD sh*-*-netbsdelf*
3065 MIPS NetBSD mips*-*-netbsd*
3066 UltraSPARC NetBSD sparc64-*-netbsd*
3068 * OBSOLETE configurations and files
3070 Configurations that have been declared obsolete in this release have
3071 been commented out. Unless there is activity to revive these
3072 configurations, the next release of GDB will have their sources
3073 permanently REMOVED.
3075 Mitsubishi D30V d30v-*-*
3076 OS/9000 i[34]86-*-os9k
3077 IBM AIX PS/2 i[3456]86-*-aix
3078 Fujitsu FR30 fr30-*-elf*
3079 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3080 Argonaut Risc Chip (ARC) arc-*-*
3081 i386 running Mach 3.0 i[3456]86-*-mach3*
3082 i386 running Mach i[3456]86-*-mach*
3083 i386 running OSF/1 i[3456]86-*osf1mk*
3084 HP/Apollo 68k Family m68*-apollo*-sysv*,
3086 m68*-hp-bsd*, m68*-hp-hpux*
3087 I960 with MON960 i960-*-coff
3089 * OBSOLETE languages
3091 CHILL, a Pascal like language used by telecommunications companies.
3093 * REMOVED configurations and files
3095 AMD 29k family via UDI a29k-amd-udi, udi29k
3096 A29K VxWorks a29k-*-vxworks
3097 AMD 29000 embedded, using EBMON a29k-none-none
3098 AMD 29000 embedded with COFF a29k-none-coff
3099 AMD 29000 embedded with a.out a29k-none-aout
3101 testsuite/gdb.hp/gdb.threads-hp/ directory
3103 * New command "set max-user-call-depth <nnn>"
3105 This command allows the user to limit the call depth of user-defined
3106 commands. The default is 1024.
3108 * Changes in FreeBSD/i386 native debugging.
3110 Support for the "generate-core-file" has been added.
3112 * New commands "dump", "append", and "restore".
3114 These commands allow data to be copied from target memory
3115 to a bfd-format or binary file (dump and append), and back
3116 from a file into memory (restore).
3118 * Improved "next/step" support on multi-processor Alpha Tru64.
3120 The previous single-step mechanism could cause unpredictable problems,
3121 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3122 of a software single-step mechanism prevents this.
3124 *** Changes in GDB 5.2.1:
3132 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3133 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3134 Fix, by Joel Brobecker imported from mainline.
3136 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3137 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3138 Fix, by Fred Fish, imported from mainline.
3140 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3141 Surprisingly enough, it works now.
3142 By Michal Ludvig, imported from mainline.
3144 i386 hardware watchpoint support:
3145 avoid misses on second run for some targets.
3146 By Pierre Muller, imported from mainline.
3148 *** Changes in GDB 5.2:
3150 * New command "set trust-readonly-sections on[off]".
3152 This command is a hint that tells gdb that read-only sections
3153 really are read-only (ie. that their contents will not change).
3154 In this mode, gdb will go to the object file rather than the
3155 target to read memory from read-only sections (such as ".text").
3156 This can be a significant performance improvement on some
3157 (notably embedded) targets.
3159 * New command "generate-core-file" (or "gcore").
3161 This new gdb command allows the user to drop a core file of the child
3162 process state at any time. So far it's been implemented only for
3163 GNU/Linux and Solaris, but should be relatively easily ported to other
3164 hosts. Argument is core file name (defaults to core.<pid>).
3166 * New command line option
3168 GDB now accepts --pid or -p followed by a process id.
3170 * Change in command line behavior -- corefiles vs. process ids.
3172 There is a subtle behavior in the way in which GDB handles
3173 command line arguments. The first non-flag argument is always
3174 a program to debug, but the second non-flag argument may either
3175 be a corefile or a process id. Previously, GDB would attempt to
3176 open the second argument as a corefile, and if that failed, would
3177 issue a superfluous error message and then attempt to attach it as
3178 a process. Now, if the second argument begins with a non-digit,
3179 it will be treated as a corefile. If it begins with a digit,
3180 GDB will attempt to attach it as a process, and if no such process
3181 is found, will then attempt to open it as a corefile.
3183 * Changes in ARM configurations.
3185 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3186 configuration is fully multi-arch.
3188 * New native configurations
3190 ARM NetBSD arm*-*-netbsd*
3191 x86 OpenBSD i[3456]86-*-openbsd*
3192 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3193 Sparc64 running FreeBSD sparc64-*-freebsd*
3197 Sanyo XStormy16 xstormy16-elf
3199 * OBSOLETE configurations and files
3201 Configurations that have been declared obsolete in this release have
3202 been commented out. Unless there is activity to revive these
3203 configurations, the next release of GDB will have their sources
3204 permanently REMOVED.
3206 AMD 29k family via UDI a29k-amd-udi, udi29k
3207 A29K VxWorks a29k-*-vxworks
3208 AMD 29000 embedded, using EBMON a29k-none-none
3209 AMD 29000 embedded with COFF a29k-none-coff
3210 AMD 29000 embedded with a.out a29k-none-aout
3212 testsuite/gdb.hp/gdb.threads-hp/ directory
3214 * REMOVED configurations and files
3216 TI TMS320C80 tic80-*-*
3218 PowerPC Solaris powerpcle-*-solaris*
3219 PowerPC Windows NT powerpcle-*-cygwin32
3220 PowerPC Netware powerpc-*-netware*
3221 Harris/CXUX m88k m88*-harris-cxux*
3222 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3223 ns32k-utek-sysv* ns32k-utek-*
3224 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3225 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3226 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3227 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3228 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3230 * Changes to command line processing
3232 The new `--args' feature can be used to specify command-line arguments
3233 for the inferior from gdb's command line.
3235 * Changes to key bindings
3237 There is a new `operate-and-get-next' function bound to `C-o'.
3239 *** Changes in GDB 5.1.1
3241 Fix compile problem on DJGPP.
3243 Fix a problem with floating-point registers on the i386 being
3246 Fix to stop GDB crashing on .debug_str debug info.
3248 Numerous documentation fixes.
3250 Numerous testsuite fixes.
3252 *** Changes in GDB 5.1:
3254 * New native configurations
3256 Alpha FreeBSD alpha*-*-freebsd*
3257 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3258 MIPS GNU/Linux mips*-*-linux*
3259 MIPS SGI Irix 6.x mips*-sgi-irix6*
3260 ia64 AIX ia64-*-aix*
3261 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3265 Motorola 68HC11 and 68HC12 m68hc11-elf
3267 UltraSparc running GNU/Linux sparc64-*-linux*
3269 * OBSOLETE configurations and files
3271 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3272 Harris/CXUX m88k m88*-harris-cxux*
3273 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3274 ns32k-utek-sysv* ns32k-utek-*
3275 TI TMS320C80 tic80-*-*
3277 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3278 PowerPC Solaris powerpcle-*-solaris*
3279 PowerPC Windows NT powerpcle-*-cygwin32
3280 PowerPC Netware powerpc-*-netware*
3281 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3282 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3283 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3284 Apple Macintosh (MPW) host N/A
3286 stuff.c (Program to stuff files into a specially prepared space in kdb)
3287 kdb-start.c (Main loop for the standalone kernel debugger)
3289 Configurations that have been declared obsolete in this release have
3290 been commented out. Unless there is activity to revive these
3291 configurations, the next release of GDB will have their sources
3292 permanently REMOVED.
3294 * REMOVED configurations and files
3296 Altos 3068 m68*-altos-*
3297 Convex c1-*-*, c2-*-*
3299 ARM RISCix arm-*-* (as host)
3303 * GDB has been converted to ISO C.
3305 GDB's source code has been converted to ISO C. In particular, the
3306 sources are fully protoized, and rely on standard headers being
3311 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3313 * The MI enabled by default.
3315 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3316 revised and enabled by default. Packages which use GDB as a debugging
3317 engine behind a UI or another front end are encouraged to switch to
3318 using the GDB/MI interface, instead of the old annotations interface
3319 which is now deprecated.
3321 * Support for debugging Pascal programs.
3323 GDB now includes support for debugging Pascal programs. The following
3324 main features are supported:
3326 - Pascal-specific data types such as sets;
3328 - automatic recognition of Pascal sources based on file-name
3331 - Pascal-style display of data types, variables, and functions;
3333 - a Pascal expression parser.
3335 However, some important features are not yet supported.
3337 - Pascal string operations are not supported at all;
3339 - there are some problems with boolean types;
3341 - Pascal type hexadecimal constants are not supported
3342 because they conflict with the internal variables format;
3344 - support for Pascal objects and classes is not full yet;
3346 - unlike Pascal, GDB is case-sensitive for symbol names.
3348 * Changes in completion.
3350 Commands such as `shell', `run' and `set args', which pass arguments
3351 to inferior programs, now complete on file names, similar to what
3352 users expect at the shell prompt.
3354 Commands which accept locations, such as `disassemble', `print',
3355 `breakpoint', `until', etc. now complete on filenames as well as
3356 program symbols. Thus, if you type "break foob TAB", and the source
3357 files linked into the programs include `foobar.c', that file name will
3358 be one of the candidates for completion. However, file names are not
3359 considered for completion after you typed a colon that delimits a file
3360 name from a name of a function in that file, as in "break foo.c:bar".
3362 `set demangle-style' completes on available demangling styles.
3364 * New platform-independent commands:
3366 It is now possible to define a post-hook for a command as well as a
3367 hook that runs before the command. For more details, see the
3368 documentation of `hookpost' in the GDB manual.
3370 * Changes in GNU/Linux native debugging.
3372 Support for debugging multi-threaded programs has been completely
3373 revised for all platforms except m68k and sparc. You can now debug as
3374 many threads as your system allows you to have.
3376 Attach/detach is supported for multi-threaded programs.
3378 Support for SSE registers was added for x86. This doesn't work for
3379 multi-threaded programs though.
3381 * Changes in MIPS configurations.
3383 Multi-arch support is enabled for all MIPS configurations.
3385 GDB can now be built as native debugger on SGI Irix 6.x systems for
3386 debugging n32 executables. (Debugging 64-bit executables is not yet
3389 * Unified support for hardware watchpoints in all x86 configurations.
3391 Most (if not all) native x86 configurations support hardware-assisted
3392 breakpoints and watchpoints in a unified manner. This support
3393 implements debug register sharing between watchpoints, which allows to
3394 put a virtually infinite number of watchpoints on the same address,
3395 and also supports watching regions up to 16 bytes with several debug
3398 The new maintenance command `maintenance show-debug-regs' toggles
3399 debugging print-outs in functions that insert, remove, and test
3400 watchpoints and hardware breakpoints.
3402 * Changes in the DJGPP native configuration.
3404 New command ``info dos sysinfo'' displays assorted information about
3405 the CPU, OS, memory, and DPMI server.
3407 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3408 display information about segment descriptors stored in GDT, LDT, and
3411 New commands ``info dos pde'' and ``info dos pte'' display entries
3412 from Page Directory and Page Tables (for now works with CWSDPMI only).
3413 New command ``info dos address-pte'' displays the Page Table entry for
3414 a given linear address.
3416 GDB can now pass command lines longer than 126 characters to the
3417 program being debugged (requires an update to the libdbg.a library
3418 which is part of the DJGPP development kit).
3420 DWARF2 debug info is now supported.
3422 It is now possible to `step' and `next' through calls to `longjmp'.
3424 * Changes in documentation.
3426 All GDB documentation was converted to GFDL, the GNU Free
3427 Documentation License.
3429 Tracepoints-related commands are now fully documented in the GDB
3432 TUI, the Text-mode User Interface, is now documented in the manual.
3434 Tracepoints-related commands are now fully documented in the GDB
3437 The "GDB Internals" manual now has an index. It also includes
3438 documentation of `ui_out' functions, GDB coding standards, x86
3439 hardware watchpoints, and memory region attributes.
3441 * GDB's version number moved to ``version.in''
3443 The Makefile variable VERSION has been replaced by the file
3444 ``version.in''. People creating GDB distributions should update the
3445 contents of this file.
3449 GUD support is now a standard part of the EMACS distribution.
3451 *** Changes in GDB 5.0:
3453 * Improved support for debugging FP programs on x86 targets
3455 Unified and much-improved support for debugging floating-point
3456 programs on all x86 targets. In particular, ``info float'' now
3457 displays the FP registers in the same format on all x86 targets, with
3458 greater level of detail.
3460 * Improvements and bugfixes in hardware-assisted watchpoints
3462 It is now possible to watch array elements, struct members, and
3463 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3464 on x86 targets no longer erroneously trigger when the address is
3467 * Improvements in the native DJGPP version of GDB
3469 The distribution now includes all the scripts and auxiliary files
3470 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3471 machines ``out of the box''.
3473 The DJGPP version can now debug programs that use signals. It is
3474 possible to catch signals that happened in the debuggee, deliver
3475 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3476 would kill the program being debugged.) Programs that hook hardware
3477 interrupts (keyboard, timer, etc.) can also be debugged.
3479 It is now possible to debug DJGPP programs that redirect their
3480 standard handles or switch them to raw (as opposed to cooked) mode, or
3481 even close them. The command ``run < foo > bar'' works as expected,
3482 and ``info terminal'' reports useful information about the debuggee's
3483 terminal, including raw/cooked mode, redirection, etc.
3485 The DJGPP version now uses termios functions for console I/O, which
3486 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3489 DOS-style file names with drive letters are now fully supported by
3492 It is now possible to debug DJGPP programs that switch their working
3493 directory. It is also possible to rerun the debuggee any number of
3494 times without restarting GDB; thus, you can use the same setup,
3495 breakpoints, etc. for many debugging sessions.
3497 * New native configurations
3499 ARM GNU/Linux arm*-*-linux*
3500 PowerPC GNU/Linux powerpc-*-linux*
3504 Motorola MCore mcore-*-*
3505 x86 VxWorks i[3456]86-*-vxworks*
3506 PowerPC VxWorks powerpc-*-vxworks*
3507 TI TMS320C80 tic80-*-*
3509 * OBSOLETE configurations
3511 Altos 3068 m68*-altos-*
3512 Convex c1-*-*, c2-*-*
3514 ARM RISCix arm-*-* (as host)
3517 Configurations that have been declared obsolete will be commented out,
3518 but the code will be left in place. If there is no activity to revive
3519 these configurations before the next release of GDB, the sources will
3520 be permanently REMOVED.
3522 * Gould support removed
3524 Support for the Gould PowerNode and NP1 has been removed.
3526 * New features for SVR4
3528 On SVR4 native platforms (such as Solaris), if you attach to a process
3529 without first loading a symbol file, GDB will now attempt to locate and
3530 load symbols from the running process's executable file.
3532 * Many C++ enhancements
3534 C++ support has been greatly improved. Overload resolution now works properly
3535 in almost all cases. RTTI support is on the way.
3537 * Remote targets can connect to a sub-program
3539 A popen(3) style serial-device has been added. This device starts a
3540 sub-process (such as a stand-alone simulator) and then communicates
3541 with that. The sub-program to run is specified using the syntax
3542 ``|<program> <args>'' vis:
3544 (gdb) set remotedebug 1
3545 (gdb) target extended-remote |mn10300-elf-sim program-args
3547 * MIPS 64 remote protocol
3549 A long standing bug in the mips64 remote protocol where by GDB
3550 expected certain 32 bit registers (ex SR) to be transfered as 32
3551 instead of 64 bits has been fixed.
3553 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3554 added to provide backward compatibility with older versions of GDB.
3556 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3558 The command ``set remotebinarydownload'' command has been replaced by
3559 ``set remote X-packet''. Other commands in ``set remote'' family
3560 include ``set remote P-packet''.
3562 * Breakpoint commands accept ranges.
3564 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3565 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3566 ``tracepoint passcount'' also accepts a range of tracepoints.
3568 * ``apropos'' command added.
3570 The ``apropos'' command searches through command names and
3571 documentation strings, printing out matches, making it much easier to
3572 try to find a command that does what you are looking for.
3576 A new machine oriented interface (MI) has been added to GDB. This
3577 interface is designed for debug environments running GDB as a separate
3578 process. This is part of the long term libGDB project. See the
3579 "GDB/MI" chapter of the GDB manual for further information. It can be
3580 enabled by configuring with:
3582 .../configure --enable-gdbmi
3584 *** Changes in GDB-4.18:
3586 * New native configurations
3588 HP-UX 10.20 hppa*-*-hpux10.20
3589 HP-UX 11.x hppa*-*-hpux11.0*
3590 M68K GNU/Linux m68*-*-linux*
3594 Fujitsu FR30 fr30-*-elf*
3595 Intel StrongARM strongarm-*-*
3596 Mitsubishi D30V d30v-*-*
3598 * OBSOLETE configurations
3600 Gould PowerNode, NP1 np1-*-*, pn-*-*
3602 Configurations that have been declared obsolete will be commented out,
3603 but the code will be left in place. If there is no activity to revive
3604 these configurations before the next release of GDB, the sources will
3605 be permanently REMOVED.
3609 As a compatibility experiment, GDB's source files buildsym.h and
3610 buildsym.c have been converted to pure standard C, no longer
3611 containing any K&R compatibility code. We believe that all systems in
3612 use today either come with a standard C compiler, or have a GCC port
3613 available. If this is not true, please report the affected
3614 configuration to bug-gdb@gnu.org immediately. See the README file for
3615 information about getting a standard C compiler if you don't have one
3620 GDB now uses readline 2.2.
3622 * set extension-language
3624 You can now control the mapping between filename extensions and source
3625 languages by using the `set extension-language' command. For instance,
3626 you can ask GDB to treat .c files as C++ by saying
3627 set extension-language .c c++
3628 The command `info extensions' lists all of the recognized extensions
3629 and their associated languages.
3631 * Setting processor type for PowerPC and RS/6000
3633 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3634 you can use the `set processor' command to specify what variant of the
3635 PowerPC family you are debugging. The command
3639 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3640 following PowerPC and RS6000 variants:
3642 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3643 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3645 403GC IBM PowerPC 403GC
3646 505 Motorola PowerPC 505
3647 860 Motorola PowerPC 860 or 850
3648 601 Motorola PowerPC 601
3649 602 Motorola PowerPC 602
3650 603 Motorola/IBM PowerPC 603 or 603e
3651 604 Motorola PowerPC 604 or 604e
3652 750 Motorola/IBM PowerPC 750 or 750
3654 At the moment, this command just tells GDB what to name the
3655 special-purpose processor registers. Since almost all the affected
3656 registers are inaccessible to user-level programs, this command is
3657 only useful for remote debugging in its present form.
3661 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3662 more extensive support for HP-UX. Added features include shared
3663 library support, kernel threads and hardware watchpoints for 11.00,
3664 support for HP's ANSI C and C++ compilers, and a compatibility mode
3665 for xdb and dbx commands.
3669 HP's donation includes the new concept of catchpoints, which is a
3670 generalization of the old catch command. On HP-UX, it is now possible
3671 to catch exec, fork, and vfork, as well as library loading.
3673 This means that the existing catch command has changed; its first
3674 argument now specifies the type of catch to be set up. See the
3675 output of "help catch" for a list of catchpoint types.
3677 * Debugging across forks
3679 On HP-UX, you can choose which process to debug when a fork() happens
3684 HP has donated a curses-based terminal user interface (TUI). To get
3685 it, build with --enable-tui. Although this can be enabled for any
3686 configuration, at present it only works for native HP debugging.
3688 * GDB remote protocol additions
3690 A new protocol packet 'X' that writes binary data is now available.
3691 Default behavior is to try 'X', then drop back to 'M' if the stub
3692 fails to respond. The settable variable `remotebinarydownload'
3693 allows explicit control over the use of 'X'.
3695 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3696 full 64-bit address. The command
3698 set remoteaddresssize 32
3700 can be used to revert to the old behaviour. For existing remote stubs
3701 the change should not be noticed, as the additional address information
3704 In order to assist in debugging stubs, you may use the maintenance
3705 command `packet' to send any text string to the stub. For instance,
3707 maint packet heythere
3709 sends the packet "$heythere#<checksum>". Note that it is very easy to
3710 disrupt a debugging session by sending the wrong packet at the wrong
3713 The compare-sections command allows you to compare section data on the
3714 target to what is in the executable file without uploading or
3715 downloading, by comparing CRC checksums.
3717 * Tracing can collect general expressions
3719 You may now collect general expressions at tracepoints. This requires
3720 further additions to the target-side stub; see tracepoint.c and
3721 doc/agentexpr.texi for further details.
3723 * mask-address variable for Mips
3725 For Mips targets, you may control the zeroing of the upper 32 bits of
3726 a 64-bit address by entering `set mask-address on'. This is mainly
3727 of interest to users of embedded R4xxx and R5xxx processors.
3729 * Higher serial baud rates
3731 GDB's serial code now allows you to specify baud rates 57600, 115200,
3732 230400, and 460800 baud. (Note that your host system may not be able
3733 to achieve all of these rates.)
3737 The i960 configuration now includes an initial implementation of a
3738 builtin simulator, contributed by Jim Wilson.
3741 *** Changes in GDB-4.17:
3743 * New native configurations
3745 Alpha GNU/Linux alpha*-*-linux*
3746 Unixware 2.x i[3456]86-unixware2*
3747 Irix 6.x mips*-sgi-irix6*
3748 PowerPC GNU/Linux powerpc-*-linux*
3749 PowerPC Solaris powerpcle-*-solaris*
3750 Sparc GNU/Linux sparc-*-linux*
3751 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3755 Argonaut Risc Chip (ARC) arc-*-*
3756 Hitachi H8/300S h8300*-*-*
3757 Matsushita MN10200 w/simulator mn10200-*-*
3758 Matsushita MN10300 w/simulator mn10300-*-*
3759 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3760 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3761 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3762 Mitsubishi D10V w/simulator d10v-*-*
3763 Mitsubishi M32R/D w/simulator m32r-*-elf*
3764 Tsqware Sparclet sparclet-*-*
3765 NEC V850 w/simulator v850-*-*
3767 * New debugging protocols
3769 ARM with RDI protocol arm*-*-*
3770 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3771 DDB and LSI variants of PMON protocol mips*-*-*
3772 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3773 PowerPC with SDS protocol powerpc{,le}-*-eabi
3774 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3778 All configurations can now understand and use the DWARF 2 debugging
3779 format. The choice is automatic, if the symbol file contains DWARF 2
3784 GDB now includes basic Java language support. This support is
3785 only useful with Java compilers that produce native machine code.
3787 * solib-absolute-prefix and solib-search-path
3789 For SunOS and SVR4 shared libraries, you may now set the prefix for
3790 loading absolute shared library symbol files, and the search path for
3791 locating non-absolute shared library symbol files.
3793 * Live range splitting
3795 GDB can now effectively debug code for which GCC has performed live
3796 range splitting as part of its optimization. See gdb/doc/LRS for
3797 more details on the expected format of the stabs information.
3801 GDB's support for the GNU Hurd, including thread debugging, has been
3802 updated to work with current versions of the Hurd.
3806 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3807 instruction set. ARM GDB automatically detects when Thumb
3808 instructions are in use, and adjusts disassembly and backtracing
3813 GDB's MIPS target configurations now handle the MIP16 16-bit
3818 GDB now includes support for overlays; if an executable has been
3819 linked such that multiple sections are based at the same address, GDB
3820 will decide which section to use for symbolic info. You can choose to
3821 control the decision manually, using overlay commands, or implement
3822 additional target-side support and use "overlay load-target" to bring
3823 in the overlay mapping. Do "help overlay" for more detail.
3827 The command "info symbol <address>" displays information about
3828 the symbol at the specified address.
3832 The standard remote protocol now includes an extension that allows
3833 asynchronous collection and display of trace data. This requires
3834 extensive support in the target-side debugging stub. Tracing mode
3835 includes a new interaction mode in GDB and new commands: see the
3836 file tracepoint.c for more details.
3840 Configurations for embedded MIPS now include a simulator contributed
3841 by Cygnus Solutions. The simulator supports the instruction sets
3842 of most MIPS variants.
3846 Sparc configurations may now include the ERC32 simulator contributed
3847 by the European Space Agency. The simulator is not built into
3848 Sparc targets by default; configure with --enable-sim to include it.
3852 For target configurations that may include multiple variants of a
3853 basic architecture (such as MIPS and SH), you may now set the
3854 architecture explicitly. "set arch" sets, "info arch" lists
3855 the possible architectures.
3857 *** Changes in GDB-4.16:
3859 * New native configurations
3861 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3862 M68K NetBSD m68k-*-netbsd*
3863 PowerPC AIX 4.x powerpc-*-aix*
3864 PowerPC MacOS powerpc-*-macos*
3865 PowerPC Windows NT powerpcle-*-cygwin32
3866 RS/6000 AIX 4.x rs6000-*-aix4*
3870 ARM with RDP protocol arm-*-*
3871 I960 with MON960 i960-*-coff
3872 MIPS VxWorks mips*-*-vxworks*
3873 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3874 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3876 Matra Sparclet sparclet-*-*
3880 The powerpc-eabi configuration now includes the PSIM simulator,
3881 contributed by Andrew Cagney, with assistance from Mike Meissner.
3882 PSIM is a very elaborate model of the PowerPC, including not only
3883 basic instruction set execution, but also details of execution unit
3884 performance and I/O hardware. See sim/ppc/README for more details.
3888 GDB now works with Solaris 2.5.
3890 * Windows 95/NT native
3892 GDB will now work as a native debugger on Windows 95 and Windows NT.
3893 To build it from source, you must use the "gnu-win32" environment,
3894 which uses a DLL to emulate enough of Unix to run the GNU tools.
3895 Further information, binaries, and sources are available at
3896 ftp.cygnus.com, under pub/gnu-win32.
3898 * dont-repeat command
3900 If a user-defined command includes the command `dont-repeat', then the
3901 command will not be repeated if the user just types return. This is
3902 useful if the command is time-consuming to run, so that accidental
3903 extra keystrokes don't run the same command many times.
3905 * Send break instead of ^C
3907 The standard remote protocol now includes an option to send a break
3908 rather than a ^C to the target in order to interrupt it. By default,
3909 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3911 * Remote protocol timeout
3913 The standard remote protocol includes a new variable `remotetimeout'
3914 that allows you to set the number of seconds before GDB gives up trying
3915 to read from the target. The default value is 2.
3917 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3919 By default GDB will automatically keep track of objects as they are
3920 loaded and unloaded by the dynamic linker. By using the command `set
3921 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3922 when shared library events occur, thus allowing you to set breakpoints
3923 in shared libraries which are explicitly loaded by the inferior.
3925 Note this feature does not work on hpux8. On hpux9 you must link
3926 /usr/lib/end.o into your program. This feature should work
3927 automatically on hpux10.
3929 * Irix 5.x hardware watchpoint support
3931 Irix 5 configurations now support the use of hardware watchpoints.
3933 * Mips protocol "SYN garbage limit"
3935 When debugging a Mips target using the `target mips' protocol, you
3936 may set the number of characters that GDB will ignore by setting
3937 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3938 every character. The default value is 1050.
3940 * Recording and replaying remote debug sessions
3942 If you set `remotelogfile' to the name of a file, gdb will write to it
3943 a recording of a remote debug session. This recording may then be
3944 replayed back to gdb using "gdbreplay". See gdbserver/README for
3945 details. This is useful when you have a problem with GDB while doing
3946 remote debugging; you can make a recording of the session and send it
3947 to someone else, who can then recreate the problem.
3949 * Speedups for remote debugging
3951 GDB includes speedups for downloading and stepping MIPS systems using
3952 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3953 and more efficient S-record downloading.
3955 * Memory use reductions and statistics collection
3957 GDB now uses less memory and reports statistics about memory usage.
3958 Try the `maint print statistics' command, for example.
3960 *** Changes in GDB-4.15:
3962 * Psymtabs for XCOFF
3964 The symbol reader for AIX GDB now uses partial symbol tables. This
3965 can greatly improve startup time, especially for large executables.
3967 * Remote targets use caching
3969 Remote targets now use a data cache to speed up communication with the
3970 remote side. The data cache could lead to incorrect results because
3971 it doesn't know about volatile variables, thus making it impossible to
3972 debug targets which use memory mapped I/O devices. `set remotecache
3973 off' turns the the data cache off.
3975 * Remote targets may have threads
3977 The standard remote protocol now includes support for multiple threads
3978 in the target system, using new protocol commands 'H' and 'T'. See
3979 gdb/remote.c for details.
3983 If GDB is configured with `--enable-netrom', then it will include
3984 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3985 acts as though it is a bank of ROM on the target board, but you can
3986 write into it over the network. GDB's support consists only of
3987 support for fast loading into the emulated ROM; to debug, you must use
3988 another protocol, such as standard remote protocol. The usual
3989 sequence is something like
3991 target nrom <netrom-hostname>
3993 target remote <netrom-hostname>:1235
3997 GDB now includes support for the Apple Macintosh, as a host only. It
3998 may be run as either an MPW tool or as a standalone application, and
3999 it can debug through the serial port. All the usual GDB commands are
4000 available, but to the target command, you must supply "serial" as the
4001 device type instead of "/dev/ttyXX". See mpw-README in the main
4002 directory for more information on how to build. The MPW configuration
4003 scripts */mpw-config.in support only a few targets, and only the
4004 mips-idt-ecoff target has been tested.
4008 GDB configuration now uses autoconf. This is not user-visible,
4009 but does simplify configuration and building.
4013 GDB now supports hpux10.
4015 *** Changes in GDB-4.14:
4017 * New native configurations
4019 x86 FreeBSD i[345]86-*-freebsd
4020 x86 NetBSD i[345]86-*-netbsd
4021 NS32k NetBSD ns32k-*-netbsd
4022 Sparc NetBSD sparc-*-netbsd
4026 A29K VxWorks a29k-*-vxworks
4027 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4028 CPU32 EST-300 emulator m68*-*-est*
4029 PowerPC ELF powerpc-*-elf
4032 * Alpha OSF/1 support for procfs
4034 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4035 possible to attach to running processes. As the mounting of the /proc
4036 filesystem is optional on the Alpha, GDB automatically determines
4037 the availability of /proc during startup. This can lead to problems
4038 if /proc is unmounted after GDB has been started.
4040 * Arguments to user-defined commands
4042 User commands may accept up to 10 arguments separated by whitespace.
4043 Arguments are accessed within the user command via $arg0..$arg9. A
4046 print $arg0 + $arg1 + $arg2
4048 To execute the command use:
4051 Defines the command "adder" which prints the sum of its three arguments.
4052 Note the arguments are text substitutions, so they may reference variables,
4053 use complex expressions, or even perform inferior function calls.
4055 * New `if' and `while' commands
4057 This makes it possible to write more sophisticated user-defined
4058 commands. Both commands take a single argument, which is the
4059 expression to evaluate, and must be followed by the commands to
4060 execute, one per line, if the expression is nonzero, the list being
4061 terminated by the word `end'. The `if' command list may include an
4062 `else' word, which causes the following commands to be executed only
4063 if the expression is zero.
4065 * Fortran source language mode
4067 GDB now includes partial support for Fortran 77. It will recognize
4068 Fortran programs and can evaluate a subset of Fortran expressions, but
4069 variables and functions may not be handled correctly. GDB will work
4070 with G77, but does not yet know much about symbols emitted by other
4073 * Better HPUX support
4075 Most debugging facilities now work on dynamic executables for HPPAs
4076 running hpux9 or later. You can attach to running dynamically linked
4077 processes, but by default the dynamic libraries will be read-only, so
4078 for instance you won't be able to put breakpoints in them. To change
4079 that behavior do the following before running the program:
4085 This will cause the libraries to be mapped private and read-write.
4086 To revert to the normal behavior, do this:
4092 You cannot set breakpoints or examine data in the library until after
4093 the library is loaded if the function/data symbols do not have
4096 GDB can now also read debug symbols produced by the HP C compiler on
4097 HPPAs (sorry, no C++, Fortran or 68k support).
4099 * Target byte order now dynamically selectable
4101 You can choose which byte order to use with a target system, via the
4102 commands "set endian big" and "set endian little", and you can see the
4103 current setting by using "show endian". You can also give the command
4104 "set endian auto", in which case GDB will use the byte order
4105 associated with the executable. Currently, only embedded MIPS
4106 configurations support dynamic selection of target byte order.
4108 * New DOS host serial code
4110 This version uses DPMI interrupts to handle buffered I/O, so you
4111 no longer need to run asynctsr when debugging boards connected to
4114 *** Changes in GDB-4.13:
4116 * New "complete" command
4118 This lists all the possible completions for the rest of the line, if it
4119 were to be given as a command itself. This is intended for use by emacs.
4121 * Trailing space optional in prompt
4123 "set prompt" no longer adds a space for you after the prompt you set. This
4124 allows you to set a prompt which ends in a space or one that does not.
4126 * Breakpoint hit counts
4128 "info break" now displays a count of the number of times the breakpoint
4129 has been hit. This is especially useful in conjunction with "ignore"; you
4130 can ignore a large number of breakpoint hits, look at the breakpoint info
4131 to see how many times the breakpoint was hit, then run again, ignoring one
4132 less than that number, and this will get you quickly to the last hit of
4135 * Ability to stop printing at NULL character
4137 "set print null-stop" will cause GDB to stop printing the characters of
4138 an array when the first NULL is encountered. This is useful when large
4139 arrays actually contain only short strings.
4141 * Shared library breakpoints
4143 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4144 breakpoints in shared libraries before the executable is run.
4146 * Hardware watchpoints
4148 There is a new hardware breakpoint for the watch command for sparclite
4149 targets. See gdb/sparclite/hw_breakpoint.note.
4151 Hardware watchpoints are also now supported under GNU/Linux.
4155 Annotations have been added. These are for use with graphical interfaces,
4156 and are still experimental. Currently only gdba.el uses these.
4158 * Improved Irix 5 support
4160 GDB now works properly with Irix 5.2.
4162 * Improved HPPA support
4164 GDB now works properly with the latest GCC and GAS.
4166 * New native configurations
4168 Sequent PTX4 i[34]86-sequent-ptx4
4169 HPPA running OSF/1 hppa*-*-osf*
4170 Atari TT running SVR4 m68*-*-sysv4*
4171 RS/6000 LynxOS rs6000-*-lynxos*
4175 OS/9000 i[34]86-*-os9k
4176 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4179 * Hitachi SH7000 and E7000-PC ICE support
4181 There is now support for communicating with the Hitachi E7000-PC ICE.
4182 This is available automatically when GDB is configured for the SH.
4186 As usual, a variety of small fixes and improvements, both generic
4187 and configuration-specific. See the ChangeLog for more detail.
4189 *** Changes in GDB-4.12:
4191 * Irix 5 is now supported
4195 GDB-4.12 on the HPPA has a number of changes which make it unable
4196 to debug the output from the currently released versions of GCC and
4197 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4198 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4199 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4202 *** Changes in GDB-4.11:
4204 * User visible changes:
4208 The "set remotedebug" option is now consistent between the mips remote
4209 target, remote targets using the gdb-specific protocol, UDI (AMD's
4210 debug protocol for the 29k) and the 88k bug monitor. It is now an
4211 integer specifying a debug level (normally 0 or 1, but 2 means more
4212 debugging info for the mips target).
4214 * DEC Alpha native support
4216 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4217 debug info, but GDB works fairly well with the DEC compiler and should
4218 work with a future GCC release. See the README file for a few
4219 Alpha-specific notes.
4221 * Preliminary thread implementation
4223 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4225 * LynxOS native and target support for 386
4227 This release has been hosted on LynxOS 2.2, and also can be configured
4228 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4231 * Improvements in C++ mangling/demangling.
4233 This release has much better g++ debugging, specifically in name
4234 mangling/demangling, virtual function calls, print virtual table,
4235 call methods, ...etc.
4237 *** Changes in GDB-4.10:
4239 * User visible changes:
4241 Remote debugging using the GDB-specific (`target remote') protocol now
4242 supports the `load' command. This is only useful if you have some
4243 other way of getting the stub to the target system, and you can put it
4244 somewhere in memory where it won't get clobbered by the download.
4246 Filename completion now works.
4248 When run under emacs mode, the "info line" command now causes the
4249 arrow to point to the line specified. Also, "info line" prints
4250 addresses in symbolic form (as well as hex).
4252 All vxworks based targets now support a user settable option, called
4253 vxworks-timeout. This option represents the number of seconds gdb
4254 should wait for responses to rpc's. You might want to use this if
4255 your vxworks target is, perhaps, a slow software simulator or happens
4256 to be on the far side of a thin network line.
4260 This release contains support for using a DEC alpha as a GDB host for
4261 cross debugging. Native alpha debugging is not supported yet.
4264 *** Changes in GDB-4.9:
4268 This is the first GDB release which is accompanied by a matching testsuite.
4269 The testsuite requires installation of dejagnu, which should be available
4270 via ftp from most sites that carry GNU software.
4274 'Cfront' style demangling has had its name changed to 'ARM' style, to
4275 emphasize that it was written from the specifications in the C++ Annotated
4276 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4277 disclaimers, it still generated too much confusion with users attempting to
4278 use gdb with AT&T cfront.
4282 GDB now uses a standard remote interface to a simulator library.
4283 So far, the library contains simulators for the Zilog Z8001/2, the
4284 Hitachi H8/300, H8/500 and Super-H.
4286 * New targets supported
4288 H8/300 simulator h8300-hitachi-hms or h8300hms
4289 H8/500 simulator h8500-hitachi-hms or h8500hms
4290 SH simulator sh-hitachi-hms or sh
4291 Z8000 simulator z8k-zilog-none or z8ksim
4292 IDT MIPS board over serial line mips-idt-ecoff
4294 Cross-debugging to GO32 targets is supported. It requires a custom
4295 version of the i386-stub.c module which is integrated with the
4296 GO32 memory extender.
4298 * New remote protocols
4300 MIPS remote debugging protocol.
4302 * New source languages supported
4304 This version includes preliminary support for Chill, a Pascal like language
4305 used by telecommunications companies. Chill support is also being integrated
4306 into the GNU compiler, but we don't know when it will be publically available.
4309 *** Changes in GDB-4.8:
4311 * HP Precision Architecture supported
4313 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4314 version of this support was available as a set of patches from the
4315 University of Utah. GDB does not support debugging of programs
4316 compiled with the HP compiler, because HP will not document their file
4317 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4318 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4320 Many problems in the preliminary version have been fixed.
4322 * Faster and better demangling
4324 We have improved template demangling and fixed numerous bugs in the GNU style
4325 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4326 character types (wchar_t) are now supported. Demangling of each symbol is now
4327 only done once, and is cached when the symbol table for a file is read in.
4328 This results in a small increase in memory usage for C programs, a moderate
4329 increase in memory usage for C++ programs, and a fantastic speedup in
4332 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4333 from the specifications in the Annotated Reference Manual, which AT&T's
4334 compiler does not actually implement.
4336 * G++ multiple inheritance compiler problem
4338 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4339 inheritance lattices was reworked to properly discover ambiguities. We
4340 recently found an example which causes this new algorithm to fail in a
4341 very subtle way, producing bad debug information for those classes.
4342 The file 'gcc.patch' (in this directory) can be applied to gcc to
4343 circumvent the problem. A future GCC release will contain a complete
4346 The previous G++ debug info problem (mentioned below for the gdb-4.7
4347 release) is fixed in gcc version 2.3.2.
4349 * Improved configure script
4351 The `configure' script will now attempt to guess your system type if
4352 you don't supply a host system type. The old scheme of supplying a
4353 host system triplet is preferable over using this. All the magic is
4354 done in the new `config.guess' script. Examine it for details.
4356 We have also brought our configure script much more in line with the FSF's
4357 version. It now supports the --with-xxx options. In particular,
4358 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4359 The resulting GDB will not be able to read arbitrary object file formats --
4360 only the format ``expected'' to be used on the configured target system.
4361 We hope to make this the default in a future release.
4363 * Documentation improvements
4365 There's new internal documentation on how to modify GDB, and how to
4366 produce clean changes to the code. We implore people to read it
4367 before submitting changes.
4369 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4370 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4371 `info' files are also provided. To build `info' files from scratch,
4372 you will need the latest `makeinfo' release, which will be available in
4373 a future texinfo-X.Y release.
4375 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4376 We're not sure exactly which versions have this problem, but it has
4377 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4378 or better. If that isn't possible, there is a patch in
4379 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4380 around this problem.
4384 GDB now supports array constants that can be used in expressions typed in by
4385 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4386 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4389 The new directory `gdb/sparclite' contains a program that demonstrates
4390 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4392 * New native hosts supported
4394 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4395 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4397 * New targets supported
4399 AMD 29k family via UDI a29k-amd-udi or udi29k
4401 * New file formats supported
4403 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4404 HPUX core files, and SCO 3.2v2 core files.
4408 Attaching to processes now works again; thanks for the many bug reports.
4410 We have also stomped on a bunch of core dumps caused by
4411 printf_filtered("%s") problems.
4413 We eliminated a copyright problem on the rpc and ptrace header files
4414 for VxWorks, which was discovered at the last minute during the 4.7
4415 release. You should now be able to build a VxWorks GDB.
4417 You can now interrupt gdb while an attached process is running. This
4418 will cause the attached process to stop, and give control back to GDB.
4420 We fixed problems caused by using too many file descriptors
4421 for reading symbols from object files and libraries. This was
4422 especially a problem for programs that used many (~100) shared
4425 The `step' command now only enters a subroutine if there is line number
4426 information for the subroutine. Otherwise it acts like the `next'
4427 command. Previously, `step' would enter subroutines if there was
4428 any debugging information about the routine. This avoids problems
4429 when using `cc -g1' on MIPS machines.
4431 * Internal improvements
4433 GDB's internal interfaces have been improved to make it easier to support
4434 debugging of multiple languages in the future.
4436 GDB now uses a common structure for symbol information internally.
4437 Minimal symbols (derived from linkage symbols in object files), partial
4438 symbols (from a quick scan of debug information), and full symbols
4439 contain a common subset of information, making it easier to write
4440 shared code that handles any of them.
4442 * New command line options
4444 We now accept --silent as an alias for --quiet.
4448 The memory-mapped-malloc library is now licensed under the GNU Library
4449 General Public License.
4451 *** Changes in GDB-4.7:
4453 * Host/native/target split
4455 GDB has had some major internal surgery to untangle the support for
4456 hosts and remote targets. Now, when you configure GDB for a remote
4457 target, it will no longer load in all of the support for debugging
4458 local programs on the host. When fully completed and tested, this will
4459 ensure that arbitrary host/target combinations are possible.
4461 The primary conceptual shift is to separate the non-portable code in
4462 GDB into three categories. Host specific code is required any time GDB
4463 is compiled on that host, regardless of the target. Target specific
4464 code relates to the peculiarities of the target, but can be compiled on
4465 any host. Native specific code is everything else: it can only be
4466 built when the host and target are the same system. Child process
4467 handling and core file support are two common `native' examples.
4469 GDB's use of /proc for controlling Unix child processes is now cleaner.
4470 It has been split out into a single module under the `target_ops' vector,
4471 plus two native-dependent functions for each system that uses /proc.
4473 * New hosts supported
4475 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4476 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4477 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4479 * New targets supported
4481 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4482 68030 and CPU32 m68030-*-*, m68332-*-*
4484 * New native hosts supported
4486 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4487 (386bsd is not well tested yet)
4488 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4490 * New file formats supported
4492 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4493 supports reading of `a.out.adobe' object files, which are an a.out
4494 format extended with minimal information about multiple sections.
4498 `show copying' is the same as the old `info copying'.
4499 `show warranty' is the same as `info warrantee'.
4500 These were renamed for consistency. The old commands continue to work.
4502 `info handle' is a new alias for `info signals'.
4504 You can now define pre-command hooks, which attach arbitrary command
4505 scripts to any command. The commands in the hook will be executed
4506 prior to the user's command. You can also create a hook which will be
4507 executed whenever the program stops. See gdb.texinfo.
4511 We now deal with Cfront style name mangling, and can even extract type
4512 info from mangled symbols. GDB can automatically figure out which
4513 symbol mangling style your C++ compiler uses.
4515 Calling of methods and virtual functions has been improved as well.
4519 The crash that occured when debugging Sun Ansi-C compiled binaries is
4520 fixed. This was due to mishandling of the extra N_SO stabs output
4523 We also finally got Ultrix 4.2 running in house, and fixed core file
4524 support, with help from a dozen people on the net.
4526 John M. Farrell discovered that the reason that single-stepping was so
4527 slow on all of the Mips based platforms (primarily SGI and DEC) was
4528 that we were trying to demangle and lookup a symbol used for internal
4529 purposes on every instruction that was being stepped through. Changing
4530 the name of that symbol so that it couldn't be mistaken for a C++
4531 mangled symbol sped things up a great deal.
4533 Rich Pixley sped up symbol lookups in general by getting much smarter
4534 about when C++ symbol mangling is necessary. This should make symbol
4535 completion (TAB on the command line) much faster. It's not as fast as
4536 we'd like, but it's significantly faster than gdb-4.6.
4540 A new user controllable variable 'call_scratch_address' can
4541 specify the location of a scratch area to be used when GDB
4542 calls a function in the target. This is necessary because the
4543 usual method of putting the scratch area on the stack does not work
4544 in systems that have separate instruction and data spaces.
4546 We integrated changes to support the 29k UDI (Universal Debugger
4547 Interface), but discovered at the last minute that we didn't have all
4548 of the appropriate copyright paperwork. We are working with AMD to
4549 resolve this, and hope to have it available soon.
4553 We have sped up the remote serial line protocol, especially for targets
4554 with lots of registers. It now supports a new `expedited status' ('T')
4555 message which can be used in place of the existing 'S' status message.
4556 This allows the remote stub to send only the registers that GDB
4557 needs to make a quick decision about single-stepping or conditional
4558 breakpoints, eliminating the need to fetch the entire register set for
4559 each instruction being stepped through.
4561 The GDB remote serial protocol now implements a write-through cache for
4562 registers, only re-reading the registers if the target has run.
4564 There is also a new remote serial stub for SPARC processors. You can
4565 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4566 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4567 processor with a serial port.
4571 Configure.in files have become much easier to read and modify. A new
4572 `table driven' format makes it more obvious what configurations are
4573 supported, and what files each one uses.
4577 There is a new opcodes library which will eventually contain all of the
4578 disassembly routines and opcode tables. At present, it only contains
4579 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4580 disassembler (binutils/objdump) to share these routines.
4582 The libiberty library is now copylefted under the GNU Library General
4583 Public License. This allows more liberal use, and was done so libg++
4584 can use it. This makes no difference to GDB, since the Library License
4585 grants all the rights from the General Public License.
4589 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4590 reference to the stabs symbol info used by the debugger. It is (as far
4591 as we know) the only published document on this fascinating topic. We
4592 encourage you to read it, compare it to the stabs information on your
4593 system, and send improvements on the document in general (to
4594 bug-gdb@prep.ai.mit.edu).
4596 And, of course, many bugs have been fixed.
4599 *** Changes in GDB-4.6:
4601 * Better support for C++ function names
4603 GDB now accepts as input the "demangled form" of C++ overloaded function
4604 names and member function names, and can do command completion on such names
4605 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4606 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4607 Make use of command completion, it is your friend.
4609 GDB also now accepts a variety of C++ mangled symbol formats. They are
4610 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4611 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4612 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4613 for the list of formats.
4615 * G++ symbol mangling problem
4617 Recent versions of gcc have a bug in how they emit debugging information for
4618 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4619 directory) can be applied to gcc to fix the problem. Alternatively, if you
4620 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4621 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4622 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4625 * New 'maintenance' command
4627 All of the commands related to hacking GDB internals have been moved out of
4628 the main command set, and now live behind the 'maintenance' command. This
4629 can also be abbreviated as 'mt'. The following changes were made:
4631 dump-me -> maintenance dump-me
4632 info all-breakpoints -> maintenance info breakpoints
4633 printmsyms -> maintenance print msyms
4634 printobjfiles -> maintenance print objfiles
4635 printpsyms -> maintenance print psymbols
4636 printsyms -> maintenance print symbols
4638 The following commands are new:
4640 maintenance demangle Call internal GDB demangler routine to
4641 demangle a C++ link name and prints the result.
4642 maintenance print type Print a type chain for a given symbol
4644 * Change to .gdbinit file processing
4646 We now read the $HOME/.gdbinit file before processing the argv arguments
4647 (e.g. reading symbol files or core files). This allows global parameters to
4648 be set, which will apply during the symbol reading. The ./.gdbinit is still
4649 read after argv processing.
4651 * New hosts supported
4653 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4655 GNU/Linux support i386-unknown-linux or linux
4657 We are also including code to support the HP/PA running BSD and HPUX. This
4658 is almost guaranteed not to work, as we didn't have time to test or build it
4659 for this release. We are including it so that the more adventurous (or
4660 masochistic) of you can play with it. We also had major problems with the
4661 fact that the compiler that we got from HP doesn't support the -g option.
4664 * New targets supported
4666 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4668 * More smarts about finding #include files
4670 GDB now remembers the compilation directory for all include files, and for
4671 all files from which C is generated (like yacc and lex sources). This
4672 greatly improves GDB's ability to find yacc/lex sources, and include files,
4673 especially if you are debugging your program from a directory different from
4674 the one that contains your sources.
4676 We also fixed a bug which caused difficulty with listing and setting
4677 breakpoints in include files which contain C code. (In the past, you had to
4678 try twice in order to list an include file that you hadn't looked at before.)
4680 * Interesting infernals change
4682 GDB now deals with arbitrary numbers of sections, where the symbols for each
4683 section must be relocated relative to that section's landing place in the
4684 target's address space. This work was needed to support ELF with embedded
4685 stabs used by Solaris-2.0.
4687 * Bug fixes (of course!)
4689 There have been loads of fixes for the following things:
4690 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4691 i960, stabs, DOS(GO32), procfs, etc...
4693 See the ChangeLog for details.
4695 *** Changes in GDB-4.5:
4697 * New machines supported (host and target)
4699 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4701 SGI Irix-4.x mips-sgi-irix4 or iris4
4703 * New malloc package
4705 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4706 Mmalloc is capable of handling mutiple heaps of memory. It is also
4707 capable of saving a heap to a file, and then mapping it back in later.
4708 This can be used to greatly speedup the startup of GDB by using a
4709 pre-parsed symbol table which lives in a mmalloc managed heap. For
4710 more details, please read mmalloc/mmalloc.texi.
4714 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4715 'help info proc' for details.
4717 * MIPS ecoff symbol table format
4719 The code that reads MIPS symbol table format is now supported on all hosts.
4720 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4723 * File name changes for MS-DOS
4725 Many files in the config directories have been renamed to make it easier to
4726 support GDB on MS-DOSe systems (which have very restrictive file name
4727 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4728 environment) is close to working but has some remaining problems. Note
4729 that debugging of DOS programs is not supported, due to limitations
4730 in the ``operating system'', but it can be used to host cross-debugging.
4732 * Cross byte order fixes
4734 Many fixes have been made to support cross debugging of Sparc and MIPS
4735 targets from hosts whose byte order differs.
4737 * New -mapped and -readnow options
4739 If memory-mapped files are available on your system through the 'mmap'
4740 system call, you can use the -mapped option on the `file' or
4741 `symbol-file' commands to cause GDB to write the symbols from your
4742 program into a reusable file. If the program you are debugging is
4743 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4744 Future GDB debugging sessions will notice the presence of this file,
4745 and will quickly map in symbol information from it, rather than reading
4746 the symbol table from the executable program. Using the '-mapped'
4747 option in a GDB `file' or `symbol-file' command has the same effect as
4748 starting GDB with the '-mapped' command-line option.
4750 You can cause GDB to read the entire symbol table immediately by using
4751 the '-readnow' option with any of the commands that load symbol table
4752 information (or on the GDB command line). This makes the command
4753 slower, but makes future operations faster.
4755 The -mapped and -readnow options are typically combined in order to
4756 build a `fred.syms' file that contains complete symbol information.
4757 A simple GDB invocation to do nothing but build a `.syms' file for future
4760 gdb -batch -nx -mapped -readnow programname
4762 The `.syms' file is specific to the host machine on which GDB is run.
4763 It holds an exact image of GDB's internal symbol table. It cannot be
4764 shared across multiple host platforms.
4766 * longjmp() handling
4768 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4769 siglongjmp() without losing control. This feature has not yet been ported to
4770 all systems. It currently works on many 386 platforms, all MIPS-based
4771 platforms (SGI, DECstation, etc), and Sun3/4.
4775 Preliminary work has been put in to support the new Solaris OS from Sun. At
4776 this time, it can control and debug processes, but it is not capable of
4781 As always, many many bug fixes. The major areas were with g++, and mipsread.
4782 People using the MIPS-based platforms should experience fewer mysterious
4783 crashes and trashed symbol tables.
4785 *** Changes in GDB-4.4:
4787 * New machines supported (host and target)
4789 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4791 BSD Reno on Vax vax-dec-bsd
4792 Ultrix on Vax vax-dec-ultrix
4794 * New machines supported (target)
4796 AMD 29000 embedded, using EBMON a29k-none-none
4800 GDB continues to improve its handling of C++. `References' work better.
4801 The demangler has also been improved, and now deals with symbols mangled as
4802 per the Annotated C++ Reference Guide.
4804 GDB also now handles `stabs' symbol information embedded in MIPS
4805 `ecoff' symbol tables. Since the ecoff format was not easily
4806 extensible to handle new languages such as C++, this appeared to be a
4807 good way to put C++ debugging info into MIPS binaries. This option
4808 will be supported in the GNU C compiler, version 2, when it is
4811 * New features for SVR4
4813 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4814 shared libraries. Debugging dynamically linked programs should present
4815 only minor differences from debugging statically linked programs.
4817 The `info proc' command will print out information about any process
4818 on an SVR4 system (including the one you are debugging). At the moment,
4819 it prints the address mappings of the process.
4821 If you bring up GDB on another SVR4 system, please send mail to
4822 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4824 * Better dynamic linking support in SunOS
4826 Reading symbols from shared libraries which contain debugging symbols
4827 now works properly. However, there remain issues such as automatic
4828 skipping of `transfer vector' code during function calls, which
4829 make it harder to debug code in a shared library, than to debug the
4830 same code linked statically.
4834 GDB is now using the latest `getopt' routines from the FSF. This
4835 version accepts the -- prefix for options with long names. GDB will
4836 continue to accept the old forms (-option and +option) as well.
4837 Various single letter abbreviations for options have been explicity
4838 added to the option table so that they won't get overshadowed in the
4839 future by other options that begin with the same letter.
4843 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4844 Many assorted bugs have been handled. Many more remain to be handled.
4845 See the various ChangeLog files (primarily in gdb and bfd) for details.
4848 *** Changes in GDB-4.3:
4850 * New machines supported (host and target)
4852 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4853 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4854 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4856 * Almost SCO Unix support
4858 We had hoped to support:
4859 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4860 (except for core file support), but we discovered very late in the release
4861 that it has problems with process groups that render gdb unusable. Sorry
4862 about that. I encourage people to fix it and post the fixes.
4864 * Preliminary ELF and DWARF support
4866 GDB can read ELF object files on System V Release 4, and can handle
4867 debugging records for C, in DWARF format, in ELF files. This support
4868 is preliminary. If you bring up GDB on another SVR4 system, please
4869 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4874 GDB now uses the latest `readline' library. One user-visible change
4875 is that two tabs will list possible command completions, which previously
4876 required typing M-? (meta-question mark, or ESC ?).
4880 The `stepi' bug that many of you noticed has been squashed.
4881 Many bugs in C++ have been handled. Many more remain to be handled.
4882 See the various ChangeLog files (primarily in gdb and bfd) for details.
4884 * State of the MIPS world (in case you wondered):
4886 GDB can understand the symbol tables emitted by the compilers
4887 supplied by most vendors of MIPS-based machines, including DEC. These
4888 symbol tables are in a format that essentially nobody else uses.
4890 Some versions of gcc come with an assembler post-processor called
4891 mips-tfile. This program is required if you want to do source-level
4892 debugging of gcc-compiled programs. I believe FSF does not ship
4893 mips-tfile with gcc version 1, but it will eventually come with gcc
4896 Debugging of g++ output remains a problem. g++ version 1.xx does not
4897 really support it at all. (If you're lucky, you should be able to get
4898 line numbers and stack traces to work, but no parameters or local
4899 variables.) With some work it should be possible to improve the
4902 When gcc version 2 is released, you will have somewhat better luck.
4903 However, even then you will get confusing results for inheritance and
4906 We will eventually provide full debugging of g++ output on
4907 DECstations. This will probably involve some kind of stabs-in-ecoff
4908 encapulation, but the details have not been worked out yet.
4911 *** Changes in GDB-4.2:
4913 * Improved configuration
4915 Only one copy of `configure' exists now, and it is not self-modifying.
4916 Porting BFD is simpler.
4920 The `step' and `next' commands now only stop at the first instruction
4921 of a source line. This prevents the multiple stops that used to occur
4922 in switch statements, for-loops, etc. `Step' continues to stop if a
4923 function that has debugging information is called within the line.
4927 Lots of small bugs fixed. More remain.
4929 * New host supported (not target)
4931 Intel 386 PC clone running Mach i386-none-mach
4934 *** Changes in GDB-4.1:
4936 * Multiple source language support
4938 GDB now has internal scaffolding to handle several source languages.
4939 It determines the type of each source file from its filename extension,
4940 and will switch expression parsing and number formatting to match the
4941 language of the function in the currently selected stack frame.
4942 You can also specifically set the language to be used, with
4943 `set language c' or `set language modula-2'.
4947 GDB now has preliminary support for the GNU Modula-2 compiler,
4948 currently under development at the State University of New York at
4949 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4950 continue through the fall of 1991 and into 1992.
4952 Other Modula-2 compilers are currently not supported, and attempting to
4953 debug programs compiled with them will likely result in an error as the
4954 symbol table is read. Feel free to work on it, though!
4956 There are hooks in GDB for strict type checking and range checking,
4957 in the `Modula-2 philosophy', but they do not currently work.
4961 GDB can now write to executable and core files (e.g. patch
4962 a variable's value). You must turn this switch on, specify
4963 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4964 by assigning a new value to a variable. Modifications take
4967 * Automatic SunOS shared library reading
4969 When you run your program, GDB automatically determines where its
4970 shared libraries (if any) have been loaded, and reads their symbols.
4971 The `share' command is no longer needed. This also works when
4972 examining core files.
4976 You can specify the number of lines that the `list' command shows.
4979 * New machines supported (host and target)
4981 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4982 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4983 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4985 * New hosts supported (not targets)
4987 IBM RT/PC: romp-ibm-aix or rtpc
4989 * New targets supported (not hosts)
4991 AMD 29000 embedded with COFF a29k-none-coff
4992 AMD 29000 embedded with a.out a29k-none-aout
4993 Ultracomputer remote kernel debug a29k-nyu-kern
4995 * New remote interfaces
5001 *** Changes in GDB-4.0:
5005 Wide output is wrapped at good places to make the output more readable.
5007 Gdb now supports cross-debugging from a host machine of one type to a
5008 target machine of another type. Communication with the target system
5009 is over serial lines. The ``target'' command handles connecting to the
5010 remote system; the ``load'' command will download a program into the
5011 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5012 also supports debugging of realtime processes running under VxWorks,
5013 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5014 stub on the target system.
5016 New CPUs supported include the AMD 29000 and Intel 960.
5018 GDB now reads object files and symbol tables via a ``binary file''
5019 library, which allows a single copy of GDB to debug programs of multiple
5020 object file types such as a.out and coff.
5022 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5023 refcard.dvi and refcard.ps are available to format it).
5026 * Control-Variable user interface simplified
5028 All variables that control the operation of the debugger can be set
5029 by the ``set'' command, and displayed by the ``show'' command.
5031 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5032 ``Show prompt'' produces the response:
5033 Gdb's prompt is new-gdb=>.
5035 What follows are the NEW set commands. The command ``help set'' will
5036 print a complete list of old and new set commands. ``help set FOO''
5037 will give a longer description of the variable FOO. ``show'' will show
5038 all of the variable descriptions and their current settings.
5040 confirm on/off: Enables warning questions for operations that are
5041 hard to recover from, e.g. rerunning the program while
5042 it is already running. Default is ON.
5044 editing on/off: Enables EMACS style command line editing
5045 of input. Previous lines can be recalled with
5046 control-P, the current line can be edited with control-B,
5047 you can search for commands with control-R, etc.
5050 history filename NAME: NAME is where the gdb command history
5051 will be stored. The default is .gdb_history,
5052 or the value of the environment variable
5055 history size N: The size, in commands, of the command history. The
5056 default is 256, or the value of the environment variable
5059 history save on/off: If this value is set to ON, the history file will
5060 be saved after exiting gdb. If set to OFF, the
5061 file will not be saved. The default is OFF.
5063 history expansion on/off: If this value is set to ON, then csh-like
5064 history expansion will be performed on
5065 command line input. The default is OFF.
5067 radix N: Sets the default radix for input and output. It can be set
5068 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5069 in the current radix, so "set radix 10" is always a no-op.
5071 height N: This integer value is the number of lines on a page. Default
5072 is 24, the current `stty rows'' setting, or the ``li#''
5073 setting from the termcap entry matching the environment
5076 width N: This integer value is the number of characters on a line.
5077 Default is 80, the current `stty cols'' setting, or the ``co#''
5078 setting from the termcap entry matching the environment
5081 Note: ``set screensize'' is obsolete. Use ``set height'' and
5082 ``set width'' instead.
5084 print address on/off: Print memory addresses in various command displays,
5085 such as stack traces and structure values. Gdb looks
5086 more ``symbolic'' if you turn this off; it looks more
5087 ``machine level'' with it on. Default is ON.
5089 print array on/off: Prettyprint arrays. New convenient format! Default
5092 print demangle on/off: Print C++ symbols in "source" form if on,
5095 print asm-demangle on/off: Same, for assembler level printouts
5098 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5101 * Support for Epoch Environment.
5103 The epoch environment is a version of Emacs v18 with windowing. One
5104 new command, ``inspect'', is identical to ``print'', except that if you
5105 are running in the epoch environment, the value is printed in its own
5109 * Support for Shared Libraries
5111 GDB can now debug programs and core files that use SunOS shared libraries.
5112 Symbols from a shared library cannot be referenced
5113 before the shared library has been linked with the program (this
5114 happens after you type ``run'' and before the function main() is entered).
5115 At any time after this linking (including when examining core files
5116 from dynamically linked programs), gdb reads the symbols from each
5117 shared library when you type the ``sharedlibrary'' command.
5118 It can be abbreviated ``share''.
5120 sharedlibrary REGEXP: Load shared object library symbols for files
5121 matching a unix regular expression. No argument
5122 indicates to load symbols for all shared libraries.
5124 info sharedlibrary: Status of loaded shared libraries.
5129 A watchpoint stops execution of a program whenever the value of an
5130 expression changes. Checking for this slows down execution
5131 tremendously whenever you are in the scope of the expression, but is
5132 quite useful for catching tough ``bit-spreader'' or pointer misuse
5133 problems. Some machines such as the 386 have hardware for doing this
5134 more quickly, and future versions of gdb will use this hardware.
5136 watch EXP: Set a watchpoint (breakpoint) for an expression.
5138 info watchpoints: Information about your watchpoints.
5140 delete N: Deletes watchpoint number N (same as breakpoints).
5141 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5142 enable N: Re-enables watchpoint number N (same as breakpoints).
5145 * C++ multiple inheritance
5147 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5150 * C++ exception handling
5152 Gdb now supports limited C++ exception handling. Besides the existing
5153 ability to breakpoint on an exception handler, gdb can breakpoint on
5154 the raising of an exception (before the stack is peeled back to the
5157 catch FOO: If there is a FOO exception handler in the dynamic scope,
5158 set a breakpoint to catch exceptions which may be raised there.
5159 Multiple exceptions (``catch foo bar baz'') may be caught.
5161 info catch: Lists all exceptions which may be caught in the
5162 current stack frame.
5165 * Minor command changes
5167 The command ``call func (arg, arg, ...)'' now acts like the print
5168 command, except it does not print or save a value if the function's result
5169 is void. This is similar to dbx usage.
5171 The ``up'' and ``down'' commands now always print the frame they end up
5172 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5173 frames without printing.
5175 * New directory command
5177 'dir' now adds directories to the FRONT of the source search path.
5178 The path starts off empty. Source files that contain debug information
5179 about the directory in which they were compiled can be found even
5180 with an empty path; Sun CC and GCC include this information. If GDB can't
5181 find your source file in the current directory, type "dir .".
5183 * Configuring GDB for compilation
5185 For normal use, type ``./configure host''. See README or gdb.texinfo
5188 GDB now handles cross debugging. If you are remotely debugging between
5189 two different machines, type ``./configure host -target=targ''.
5190 Host is the machine where GDB will run; targ is the machine
5191 where the program that you are debugging will run.