1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.5
6 * New command line options:
8 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
9 other initialization files, unlike -nx which disables all of them.
13 ** Vectors can be created with gdb.Type.vector.
15 ** Python's atexit.register now works in GDB.
17 * New Python-based convenience functions:
19 ** $_memeq(buf1, buf2, length)
20 ** $_streq(str1, str2)
22 ** $_regex(str, regex)
24 * The 'cd' command now defaults to using '~' (the home directory) if not
27 * New configure options
29 --enable-libmcheck/--disable-libmcheck
30 By default, development versions are built with -lmcheck on hosts
31 that support it, in order to help track memory corruption issues.
32 Release versions, on the other hand, are built without -lmcheck
33 by default. The --enable-libmcheck/--disable-libmcheck configure
34 options allow the user to override that default.
36 * New commands (for set/show, see "New options" below)
39 List the BFDs known to GDB.
41 python-interactive [command]
43 Start a Python interactive prompt, or evaluate the optional command
44 and print the result of expressions.
47 "py" is a new alias for "python".
51 ** For the Renesas Super-H architecture, the "regs" command has been removed
52 (has been deprecated in GDB 7.5), and "info all-registers" should be used
57 ** Command parameter changes are now notified using new async record
59 ** Trace frame changes caused by command "tfind" are now notified using
60 new async record "=traceframe-changed".
61 ** The creation and deletion of trace state variables are now notified
62 using new async records "=tsv-created" and "=tsv-deleted".
63 ** The start and stop of process record are now notified using new
64 async record "=record-started" and "=record-stopped".
66 *** Changes in GDB 7.5
68 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
69 for more x32 ABI info.
71 * GDB now supports access to MIPS DSP registers on Linux targets.
73 * GDB now supports debugging microMIPS binaries.
75 * The "info os" command on GNU/Linux can now display information on
76 several new classes of objects managed by the operating system:
77 "info os procgroups" lists process groups
78 "info os files" lists file descriptors
79 "info os sockets" lists internet-domain sockets
80 "info os shm" lists shared-memory regions
81 "info os semaphores" lists semaphores
82 "info os msg" lists message queues
83 "info os modules" lists loaded kernel modules
85 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
86 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
87 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
88 options and inspect the probe arguments using the new $_probe_arg family
89 of convenience variables. You can obtain more information about SystemTap
90 in <http://sourceware.org/systemtap/>.
92 * GDB now supports reversible debugging on ARM, it allows you to
93 debug basic ARM and THUMB instructions, and provides
94 record/replay support.
96 * The option "symbol-reloading" has been deleted as it is no longer used.
100 ** GDB commands implemented in Python can now be put in command class
103 ** The "maint set python print-stack on|off" is now deleted.
105 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
106 apply "flag enum"-style pretty-printing to any enum.
108 ** gdb.lookup_symbol can now work when there is no current frame.
110 ** gdb.Symbol now has a 'line' attribute, holding the line number in
111 the source at which the symbol was defined.
113 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
114 method 'value'. The former indicates whether the symbol needs a
115 frame in order to compute its value, and the latter computes the
118 ** A new method 'referenced_value' on gdb.Value objects which can
119 dereference pointer as well as C++ reference values.
121 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
122 which return the global and static blocks (as gdb.Block objects),
123 of the underlying symbol table, respectively.
125 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
126 object associated with a PC value.
128 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
129 of the address range occupied by code for the current source line.
131 * Go language support.
132 GDB now supports debugging programs written in the Go programming
135 * GDBserver now supports stdio connections.
136 E.g. (gdb) target remote | ssh myhost gdbserver - hello
138 * The binary "gdbtui" can no longer be built or installed.
139 Use "gdb -tui" instead.
141 * GDB will now print "flag" enums specially. A flag enum is one where
142 all the enumerator values have no bits in common when pairwise
143 "and"ed. When printing a value whose type is a flag enum, GDB will
144 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
145 (gdb) print (enum E) 3
148 * The filename part of a linespec will now match trailing components
149 of a source file name. For example, "break gcc/expr.c:1000" will
150 now set a breakpoint in build/gcc/expr.c, but not
153 * The "info proc" and "generate-core-file" commands will now also
154 work on remote targets connected to GDBserver on Linux.
156 * The command "info catch" has been removed. It has been disabled
159 * The "catch exception" and "catch assert" commands now accept
160 a condition at the end of the command, much like the "break"
161 command does. For instance:
163 (gdb) catch exception Constraint_Error if Barrier = True
165 Previously, it was possible to add a condition to such catchpoints,
166 but it had to be done as a second step, after the catchpoint had been
167 created, using the "condition" command.
169 * The "info static-tracepoint-marker" command will now also work on
170 native Linux targets with in-process agent.
172 * GDB can now set breakpoints on inlined functions.
174 * The .gdb_index section has been updated to include symbols for
175 inlined functions. GDB will ignore older .gdb_index sections by
176 default, which could cause symbol files to be loaded more slowly
177 until their .gdb_index sections can be recreated. The new command
178 "set use-deprecated-index-sections on" will cause GDB to use any older
179 .gdb_index sections it finds. This will restore performance, but the
180 ability to set breakpoints on inlined functions will be lost in symbol
181 files with older .gdb_index sections.
183 The .gdb_index section has also been updated to record more information
184 about each symbol. This speeds up the "info variables", "info functions"
185 and "info types" commands when used with programs having the .gdb_index
186 section, as well as speeding up debugging with shared libraries using
187 the .gdb_index section.
189 * Ada support for GDB/MI Variable Objects has been added.
191 * GDB can now support 'breakpoint always-inserted mode' in 'record'
196 ** New command -info-os is the MI equivalent of "info os".
198 ** Output logs ("set logging" and related) now include MI output.
202 ** "set use-deprecated-index-sections on|off"
203 "show use-deprecated-index-sections on|off"
204 Controls the use of deprecated .gdb_index sections.
206 ** "catch load" and "catch unload" can be used to stop when a shared
207 library is loaded or unloaded, respectively.
209 ** "enable count" can be used to auto-disable a breakpoint after
212 ** "info vtbl" can be used to show the virtual method tables for
213 C++ and Java objects.
215 ** "explore" and its sub commands "explore value" and "explore type"
216 can be used to reccursively explore values and types of
217 expressions. These commands are available only if GDB is
218 configured with '--with-python'.
220 ** "info auto-load" shows status of all kinds of auto-loaded files,
221 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
222 sequences of commands files, "info auto-load python-scripts"
223 shows status of auto-loading Python script files,
224 "info auto-load local-gdbinit" shows status of loading init file
225 (.gdbinit) from current directory and "info auto-load libthread-db" shows
226 status of inferior specific thread debugging shared library loading.
228 ** "info auto-load-scripts", "set auto-load-scripts on|off"
229 and "show auto-load-scripts" commands have been deprecated, use their
230 "info auto-load python-scripts", "set auto-load python-scripts on|off"
231 and "show auto-load python-scripts" counterparts instead.
233 ** "dprintf location,format,args..." creates a dynamic printf, which
234 is basically a breakpoint that does a printf and immediately
235 resumes your program's execution, so it is like a printf that you
236 can insert dynamically at runtime instead of at compiletime.
238 ** "set print symbol"
240 Controls whether GDB attempts to display the symbol, if any,
241 corresponding to addresses it prints. This defaults to "on", but
242 you can set it to "off" to restore GDB's previous behavior.
244 * Deprecated commands
246 ** For the Renesas Super-H architecture, the "regs" command has been
247 deprecated, and "info all-registers" should be used instead.
251 Renesas RL78 rl78-*-elf
252 HP OpenVMS ia64 ia64-hp-openvms*
254 * GDBserver supports evaluation of breakpoint conditions. When
255 support is advertised by GDBserver, GDB may be told to send the
256 breakpoint conditions in bytecode form to GDBserver. GDBserver
257 will only report the breakpoint trigger to GDB when its condition
263 show mips compression
264 Select the compressed ISA encoding used in functions that have no symbol
265 information available. The encoding can be set to either of:
268 and is updated automatically from ELF file flags if available.
270 set breakpoint condition-evaluation
271 show breakpoint condition-evaluation
272 Control whether breakpoint conditions are evaluated by GDB ("host") or by
273 GDBserver ("target"). Default option "auto" chooses the most efficient
275 This option can improve debugger efficiency depending on the speed of the
279 Disable auto-loading globally.
282 Show auto-loading setting of all kinds of auto-loaded files.
284 set auto-load gdb-scripts on|off
285 show auto-load gdb-scripts
286 Control auto-loading of GDB canned sequences of commands files.
288 set auto-load python-scripts on|off
289 show auto-load python-scripts
290 Control auto-loading of Python script files.
292 set auto-load local-gdbinit on|off
293 show auto-load local-gdbinit
294 Control loading of init file (.gdbinit) from current directory.
296 set auto-load libthread-db on|off
297 show auto-load libthread-db
298 Control auto-loading of inferior specific thread debugging shared library.
300 set auto-load scripts-directory <dir1>[:<dir2>...]
301 show auto-load scripts-directory
302 Set a list of directories from which to load auto-loaded scripts.
303 Automatically loaded Python scripts and GDB scripts are located in one
304 of the directories listed by this option.
305 The delimiter (':' above) may differ according to the host platform.
307 set auto-load safe-path <dir1>[:<dir2>...]
308 show auto-load safe-path
309 Set a list of directories from which it is safe to auto-load files.
310 The delimiter (':' above) may differ according to the host platform.
312 set debug auto-load on|off
314 Control display of debugging info for auto-loading the files above.
316 set dprintf-style gdb|call|agent
318 Control the way in which a dynamic printf is performed; "gdb"
319 requests a GDB printf command, while "call" causes dprintf to call a
320 function in the inferior. "agent" requests that the target agent
321 (such as GDBserver) do the printing.
323 set dprintf-function <expr>
324 show dprintf-function
325 set dprintf-channel <expr>
327 Set the function and optional first argument to the call when using
328 the "call" style of dynamic printf.
330 set disconnected-dprintf on|off
331 show disconnected-dprintf
332 Control whether agent-style dynamic printfs continue to be in effect
333 after GDB disconnects.
335 * New configure options
338 Configure default value for the 'set auto-load scripts-directory'
339 setting above. It defaults to '$debugdir:$datadir/auto-load',
340 $debugdir representing global debugging info directories (available
341 via 'show debug-file-directory') and $datadir representing GDB's data
342 directory (available via 'show data-directory').
344 --with-auto-load-safe-path
345 Configure default value for the 'set auto-load safe-path' setting
346 above. It defaults to the --with-auto-load-dir setting.
348 --without-auto-load-safe-path
349 Set 'set auto-load safe-path' to '/', effectively disabling this
354 z0/z1 conditional breakpoints extension
356 The z0/z1 breakpoint insertion packets have been extended to carry
357 a list of conditional expressions over to the remote stub depending on the
358 condition evaluation mode. The use of this extension can be controlled
359 via the "set remote conditional-breakpoints-packet" command.
363 Specify the signals which the remote stub may pass to the debugged
364 program without GDB involvement.
366 * New command line options
368 --init-command=FILE, -ix Like --command, -x but execute it
369 before loading inferior.
370 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
371 execute it before loading inferior.
373 *** Changes in GDB 7.4
375 * GDB now handles ambiguous linespecs more consistently; the existing
376 FILE:LINE support has been expanded to other types of linespecs. A
377 breakpoint will now be set on all matching locations in all
378 inferiors, and locations will be added or removed according to
381 * GDB now allows you to skip uninteresting functions and files when
382 stepping with the "skip function" and "skip file" commands.
384 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
385 and "show remote hardware-watchpoint-length-limit". These allows to
386 set or show the maximum length limit (in bytes) of a remote
387 target hardware watchpoint.
389 This allows e.g. to use "unlimited" hardware watchpoints with the
390 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
391 watchpoints are slower than real hardware watchpoints but are
392 significantly faster than gdb software watchpoints.
396 ** The register_pretty_printer function in module gdb.printing now takes
397 an optional `replace' argument. If True, the new printer replaces any
400 ** The "maint set python print-stack on|off" command has been
401 deprecated and will be deleted in GDB 7.5.
402 A new command: "set python print-stack none|full|message" has
403 replaced it. Additionally, the default for "print-stack" is
404 now "message", which just prints the error message without
407 ** A prompt substitution hook (prompt_hook) is now available to the
410 ** A new Python module, gdb.prompt has been added to the GDB Python
411 modules library. This module provides functionality for
412 escape sequences in prompts (used by set/show
413 extended-prompt). These escape sequences are replaced by their
416 ** Python commands and convenience-functions located in
417 'data-directory'/python/gdb/command and
418 'data-directory'/python/gdb/function are now automatically loaded
421 ** Blocks now provide four new attributes. global_block and
422 static_block will return the global and static blocks
423 respectively. is_static and is_global are boolean attributes
424 that indicate if the block is one of those two types.
426 ** Symbols now provide the "type" attribute, the type of the symbol.
428 ** The "gdb.breakpoint" function has been deprecated in favor of
431 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
432 of a function. This class is based on the "finish" command
433 available in the CLI.
435 ** Type objects for struct and union types now allow access to
436 the fields using standard Python dictionary (mapping) methods.
437 For example, "some_type['myfield']" now works, as does
440 ** A new event "gdb.new_objfile" has been added, triggered by loading a
443 ** A new function, "deep_items" has been added to the gdb.types
444 module in the GDB Python modules library. This function returns
445 an iterator over the fields of a struct or union type. Unlike
446 the standard Python "iteritems" method, it will recursively traverse
447 any anonymous fields.
451 ** "*stopped" events can report several new "reason"s, such as
454 ** Breakpoint changes are now notified using new async records, like
455 "=breakpoint-modified".
457 ** New command -ada-task-info.
459 * libthread-db-search-path now supports two special values: $sdir and $pdir.
460 $sdir specifies the default system locations of shared libraries.
461 $pdir specifies the directory where the libpthread used by the application
464 GDB no longer looks in $sdir and $pdir after it has searched the directories
465 mentioned in libthread-db-search-path. If you want to search those
466 directories, they must be specified in libthread-db-search-path.
467 The default value of libthread-db-search-path on GNU/Linux and Solaris
468 systems is now "$sdir:$pdir".
470 $pdir is not supported by gdbserver, it is currently ignored.
471 $sdir is supported by gdbserver.
473 * New configure option --with-iconv-bin.
474 When using the internationalization support like the one in the GNU C
475 library, GDB will invoke the "iconv" program to get a list of supported
476 character sets. If this program lives in a non-standard location, one can
477 use this option to specify where to find it.
479 * When natively debugging programs on PowerPC BookE processors running
480 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
481 watchpoints, which specify a mask in addition to an address to watch.
482 The mask specifies that some bits of an address (the bits which are
483 reset in the mask) should be ignored when matching the address accessed
484 by the inferior against the watchpoint address. See the "PowerPC Embedded"
485 section in the user manual for more details.
487 * The new option --once causes GDBserver to stop listening for connections once
488 the first connection is made. The listening port used by GDBserver will
489 become available after that.
491 * New commands "info macros" and "alias" have been added.
493 * New function parameters suffix @entry specifies value of function parameter
494 at the time the function got called. Entry values are available only since
500 "!" is now an alias of the "shell" command.
501 Note that no space is needed between "!" and SHELL COMMAND.
505 watch EXPRESSION mask MASK_VALUE
506 The watch command now supports the mask argument which allows creation
507 of masked watchpoints, if the current architecture supports this feature.
509 info auto-load-scripts [REGEXP]
510 This command was formerly named "maintenance print section-scripts".
511 It is now generally useful and is no longer a maintenance-only command.
513 info macro [-all] [--] MACRO
514 The info macro command has new options `-all' and `--'. The first for
515 printing all definitions of a macro. The second for explicitly specifying
516 the end of arguments and the beginning of the macro name in case the macro
517 name starts with a hyphen.
519 collect[/s] EXPRESSIONS
520 The tracepoint collect command now takes an optional modifier "/s"
521 that directs it to dereference pointer-to-character types and
522 collect the bytes of memory up to a zero byte. The behavior is
523 similar to what you see when you use the regular print command on a
524 string. An optional integer following the "/s" sets a bound on the
525 number of bytes that will be collected.
528 The trace start command now interprets any supplied arguments as a
529 note to be recorded with the trace run, with an effect similar to
530 setting the variable trace-notes.
533 The trace stop command now interprets any arguments as a note to be
534 mentioned along with the tstatus report that the trace was stopped
535 with a command. The effect is similar to setting the variable
538 * Tracepoints can now be enabled and disabled at any time after a trace
539 experiment has been started using the standard "enable" and "disable"
540 commands. It is now possible to start a trace experiment with no enabled
541 tracepoints; GDB will display a warning, but will allow the experiment to
542 begin, assuming that tracepoints will be enabled as needed while the trace
545 * Fast tracepoints on 32-bit x86-architectures can now be placed at
546 locations with 4-byte instructions, when they were previously
547 limited to locations with instructions of 5 bytes or longer.
551 set debug dwarf2-read
552 show debug dwarf2-read
553 Turns on or off display of debugging messages related to reading
554 DWARF debug info. The default is off.
556 set debug symtab-create
557 show debug symtab-create
558 Turns on or off display of debugging messages related to symbol table
559 creation. The default is off.
563 Set the GDB prompt, and allow escape sequences to be inserted to
564 display miscellaneous information (see 'help set extended-prompt'
565 for the list of sequences). This prompt (and any information
566 accessed through the escape sequences) is updated every time the
569 set print entry-values (both|compact|default|if-needed|no|only|preferred)
570 show print entry-values
571 Set printing of frame argument values at function entry. In some cases
572 GDB can determine the value of function argument which was passed by the
573 function caller, even if the value was modified inside the called function.
575 set debug entry-values
576 show debug entry-values
577 Control display of debugging info for determining frame argument values at
578 function entry and virtual tail call frames.
580 set basenames-may-differ
581 show basenames-may-differ
582 Set whether a source file may have multiple base names.
583 (A "base name" is the name of a file with the directory part removed.
584 Example: The base name of "/home/user/hello.c" is "hello.c".)
585 If set, GDB will canonicalize file names (e.g., expand symlinks)
586 before comparing them. Canonicalization is an expensive operation,
587 but it allows the same file be known by more than one base name.
588 If not set (the default), all source files are assumed to have just
589 one base name, and gdb will do file name comparisons more efficiently.
595 Set a user name and notes for the current and any future trace runs.
596 This is useful for long-running and/or disconnected traces, to
597 inform others (or yourself) as to who is running the trace, supply
598 contact information, or otherwise explain what is going on.
601 show trace-stop-notes
602 Set a note attached to the trace run, that is displayed when the
603 trace has been stopped by a tstop command. This is useful for
604 instance as an explanation, if you are stopping a trace run that was
605 started by someone else.
611 Dynamically enable a tracepoint in a started trace experiment.
615 Dynamically disable a tracepoint in a started trace experiment.
619 Set the user and notes of the trace run.
623 Query the current status of a tracepoint.
627 Query the minimum length of instruction at which a fast tracepoint may
630 * Dcache size (number of lines) and line-size are now runtime-configurable
631 via "set dcache line" and "set dcache line-size" commands.
635 Texas Instruments TMS320C6x tic6x-*-*
639 Renesas RL78 rl78-*-elf
641 *** Changes in GDB 7.3.1
643 * The build failure for NetBSD and OpenBSD targets have now been fixed.
645 *** Changes in GDB 7.3
647 * GDB has a new command: "thread find [REGEXP]".
648 It finds the thread id whose name, target id, or thread extra info
649 matches the given regular expression.
651 * The "catch syscall" command now works on mips*-linux* targets.
653 * The -data-disassemble MI command now supports modes 2 and 3 for
654 dumping the instruction opcodes.
656 * New command line options
658 -data-directory DIR Specify DIR as the "data-directory".
659 This is mostly for testing purposes.
661 * The "maint set python auto-load on|off" command has been renamed to
662 "set auto-load-scripts on|off".
664 * GDB has a new command: "set directories".
665 It is like the "dir" command except that it replaces the
666 source path list instead of augmenting it.
668 * GDB now understands thread names.
670 On GNU/Linux, "info threads" will display the thread name as set by
671 prctl or pthread_setname_np.
673 There is also a new command, "thread name", which can be used to
674 assign a name internally for GDB to display.
677 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
678 has been integrated into GDB.
682 ** The function gdb.Write now accepts an optional keyword 'stream'.
683 This keyword, when provided, will direct the output to either
684 stdout, stderr, or GDB's logging output.
686 ** Parameters can now be be sub-classed in Python, and in particular
687 you may implement the get_set_doc and get_show_doc functions.
688 This improves how Parameter set/show documentation is processed
689 and allows for more dynamic content.
691 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
692 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
693 have an is_valid method.
695 ** Breakpoints can now be sub-classed in Python, and in particular
696 you may implement a 'stop' function that is executed each time
697 the inferior reaches that breakpoint.
699 ** New function gdb.lookup_global_symbol looks up a global symbol.
701 ** GDB values in Python are now callable if the value represents a
702 function. For example, if 'some_value' represents a function that
703 takes two integer parameters and returns a value, you can call
704 that function like so:
706 result = some_value (10,20)
708 ** Module gdb.types has been added.
709 It contains a collection of utilities for working with gdb.Types objects:
710 get_basic_type, has_field, make_enum_dict.
712 ** Module gdb.printing has been added.
713 It contains utilities for writing and registering pretty-printers.
714 New classes: PrettyPrinter, SubPrettyPrinter,
715 RegexpCollectionPrettyPrinter.
716 New function: register_pretty_printer.
718 ** New commands "info pretty-printers", "enable pretty-printer" and
719 "disable pretty-printer" have been added.
721 ** gdb.parameter("directories") is now available.
723 ** New function gdb.newest_frame returns the newest frame in the
726 ** The gdb.InferiorThread class has a new "name" attribute. This
727 holds the thread's name.
729 ** Python Support for Inferior events.
730 Python scripts can add observers to be notified of events
731 occurring in the process being debugged.
732 The following events are currently supported:
733 - gdb.events.cont Continue event.
734 - gdb.events.exited Inferior exited event.
735 - gdb.events.stop Signal received, and Breakpoint hit events.
739 ** GDB now puts template parameters in scope when debugging in an
740 instantiation. For example, if you have:
742 template<int X> int func (void) { return X; }
744 then if you step into func<5>, "print X" will show "5". This
745 feature requires proper debuginfo support from the compiler; it
746 was added to GCC 4.5.
748 ** The motion commands "next", "finish", "until", and "advance" now
749 work better when exceptions are thrown. In particular, GDB will
750 no longer lose control of the inferior; instead, the GDB will
751 stop the inferior at the point at which the exception is caught.
752 This functionality requires a change in the exception handling
753 code that was introduced in GCC 4.5.
755 * GDB now follows GCC's rules on accessing volatile objects when
756 reading or writing target state during expression evaluation.
757 One notable difference to prior behavior is that "print x = 0"
758 no longer generates a read of x; the value of the assignment is
759 now always taken directly from the value being assigned.
761 * GDB now has some support for using labels in the program's source in
762 linespecs. For instance, you can use "advance label" to continue
763 execution to a label.
765 * GDB now has support for reading and writing a new .gdb_index
766 section. This section holds a fast index of DWARF debugging
767 information and can be used to greatly speed up GDB startup and
768 operation. See the documentation for `save gdb-index' for details.
770 * The "watch" command now accepts an optional "-location" argument.
771 When used, this causes GDB to watch the memory referred to by the
772 expression. Such a watchpoint is never deleted due to it going out
775 * GDB now supports thread debugging of core dumps on GNU/Linux.
777 GDB now activates thread debugging using the libthread_db library
778 when debugging GNU/Linux core dumps, similarly to when debugging
779 live processes. As a result, when debugging a core dump file, GDB
780 is now able to display pthread_t ids of threads. For example, "info
781 threads" shows the same output as when debugging the process when it
782 was live. In earlier releases, you'd see something like this:
785 * 1 LWP 6780 main () at main.c:10
787 While now you see this:
790 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
792 It is also now possible to inspect TLS variables when debugging core
795 When debugging a core dump generated on a machine other than the one
796 used to run GDB, you may need to point GDB at the correct
797 libthread_db library with the "set libthread-db-search-path"
798 command. See the user manual for more details on this command.
800 * When natively debugging programs on PowerPC BookE processors running
801 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
802 which stop execution of the inferior whenever it executes an instruction
803 at any address within the specified range. See the "PowerPC Embedded"
804 section in the user manual for more details.
806 * New features in the GDB remote stub, GDBserver
808 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
809 and i686 LynxOS (version 5.x).
811 ** GDBserver is now supported on Blackfin Linux.
813 * New native configurations
815 ia64 HP-UX ia64-*-hpux*
819 Analog Devices, Inc. Blackfin Processor bfin-*
821 * Ada task switching is now supported on sparc-elf targets when
822 debugging a program using the Ravenscar Profile. For more information,
823 see the "Tasking Support when using the Ravenscar Profile" section
824 in the GDB user manual.
826 * Guile support was removed.
828 * New features in the GNU simulator
830 ** The --map-info flag lists all known core mappings.
832 ** CFI flashes may be simulated via the "cfi" device.
834 *** Changes in GDB 7.2
836 * Shared library support for remote targets by default
838 When GDB is configured for a generic, non-OS specific target, like
839 for example, --target=arm-eabi or one of the many *-*-elf targets,
840 GDB now queries remote stubs for loaded shared libraries using the
841 `qXfer:libraries:read' packet. Previously, shared library support
842 was always disabled for such configurations.
846 ** Argument Dependent Lookup (ADL)
848 In C++ ADL lookup directs function search to the namespaces of its
849 arguments even if the namespace has not been imported.
859 Here the compiler will search for `foo' in the namespace of 'b'
860 and find A::foo. GDB now supports this. This construct is commonly
861 used in the Standard Template Library for operators.
863 ** Improved User Defined Operator Support
865 In addition to member operators, GDB now supports lookup of operators
866 defined in a namespace and imported with a `using' directive, operators
867 defined in the global scope, operators imported implicitly from an
868 anonymous namespace, and the ADL operators mentioned in the previous
870 GDB now also supports proper overload resolution for all the previously
871 mentioned flavors of operators.
873 ** static const class members
875 Printing of static const class members that are initialized in the
876 class definition has been fixed.
878 * Windows Thread Information Block access.
880 On Windows targets, GDB now supports displaying the Windows Thread
881 Information Block (TIB) structure. This structure is visible either
882 by using the new command `info w32 thread-information-block' or, by
883 dereferencing the new convenience variable named `$_tlb', a
884 thread-specific pointer to the TIB. This feature is also supported
885 when remote debugging using GDBserver.
889 Static tracepoints are calls in the user program into a tracing
890 library. One such library is a port of the LTTng kernel tracer to
891 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
892 When debugging with GDBserver, GDB now supports combining the GDB
893 tracepoint machinery with such libraries. For example: the user can
894 use GDB to probe a static tracepoint marker (a call from the user
895 program into the tracing library) with the new "strace" command (see
896 "New commands" below). This creates a "static tracepoint" in the
897 breakpoint list, that can be manipulated with the same feature set
898 as fast and regular tracepoints. E.g., collect registers, local and
899 global variables, collect trace state variables, and define
900 tracepoint conditions. In addition, the user can collect extra
901 static tracepoint marker specific data, by collecting the new
902 $_sdata internal variable. When analyzing the trace buffer, you can
903 inspect $_sdata like any other variable available to GDB. For more
904 information, see the "Tracepoints" chapter in GDB user manual. New
905 remote packets have been defined to support static tracepoints, see
906 the "New remote packets" section below.
908 * Better reconstruction of tracepoints after disconnected tracing
910 GDB will attempt to download the original source form of tracepoint
911 definitions when starting a trace run, and then will upload these
912 upon reconnection to the target, resulting in a more accurate
913 reconstruction of the tracepoints that are in use on the target.
917 You can now exercise direct control over the ways that GDB can
918 affect your program. For instance, you can disallow the setting of
919 breakpoints, so that the program can run continuously (assuming
920 non-stop mode). In addition, the "observer" variable is available
921 to switch all of the different controls; in observer mode, GDB
922 cannot affect the target's behavior at all, which is useful for
923 tasks like diagnosing live systems in the field.
925 * The new convenience variable $_thread holds the number of the
932 Return the address of the Windows Thread Information Block of a given thread.
936 In response to several of the tracepoint packets, the target may now
937 also respond with a number of intermediate `qRelocInsn' request
938 packets before the final result packet, to have GDB handle
939 relocating an instruction to execute at a different address. This
940 is particularly useful for stubs that support fast tracepoints. GDB
941 reports support for this feature in the qSupported packet.
945 List static tracepoint markers in the target program.
949 List static tracepoint markers at a given address in the target
952 qXfer:statictrace:read
954 Read the static trace data collected (by a `collect $_sdata'
955 tracepoint action). The remote stub reports support for this packet
956 to gdb's qSupported query.
960 Send the current settings of GDB's permission flags.
964 Send part of the source (textual) form of a tracepoint definition,
965 which includes location, conditional, and action list.
967 * The source command now accepts a -s option to force searching for the
968 script in the source search path even if the script name specifies
971 * New features in the GDB remote stub, GDBserver
973 - GDBserver now support tracepoints (including fast tracepoints, and
974 static tracepoints). The feature is currently supported by the
975 i386-linux and amd64-linux builds. See the "Tracepoints support
976 in gdbserver" section in the manual for more information.
978 GDBserver JIT compiles the tracepoint's conditional agent
979 expression bytecode into native code whenever possible for low
980 overhead dynamic tracepoints conditionals. For such tracepoints,
981 an expression that examines program state is evaluated when the
982 tracepoint is reached, in order to determine whether to capture
983 trace data. If the condition is simple and false, processing the
984 tracepoint finishes very quickly and no data is gathered.
986 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
987 for static tracepoints support.
989 - GDBserver now supports x86_64 Windows 64-bit debugging.
991 * GDB now sends xmlRegisters= in qSupported packet to indicate that
992 it understands register description.
994 * The --batch flag now disables pagination and queries.
996 * X86 general purpose registers
998 GDB now supports reading/writing byte, word and double-word x86
999 general purpose registers directly. This means you can use, say,
1000 $ah or $ax to refer, respectively, to the byte register AH and
1001 16-bit word register AX that are actually portions of the 32-bit
1002 register EAX or 64-bit register RAX.
1004 * The `commands' command now accepts a range of breakpoints to modify.
1005 A plain `commands' following a command that creates multiple
1006 breakpoints affects all the breakpoints set by that command. This
1007 applies to breakpoints set by `rbreak', and also applies when a
1008 single `break' command creates multiple breakpoints (e.g.,
1009 breakpoints on overloaded c++ functions).
1011 * The `rbreak' command now accepts a filename specification as part of
1012 its argument, limiting the functions selected by the regex to those
1013 in the specified file.
1015 * Support for remote debugging Windows and SymbianOS shared libraries
1016 from Unix hosts has been improved. Non Windows GDB builds now can
1017 understand target reported file names that follow MS-DOS based file
1018 system semantics, such as file names that include drive letters and
1019 use the backslash character as directory separator. This makes it
1020 possible to transparently use the "set sysroot" and "set
1021 solib-search-path" on Unix hosts to point as host copies of the
1022 target's shared libraries. See the new command "set
1023 target-file-system-kind" described below, and the "Commands to
1024 specify files" section in the user manual for more information.
1028 eval template, expressions...
1029 Convert the values of one or more expressions under the control
1030 of the string template to a command line, and call it.
1032 set target-file-system-kind unix|dos-based|auto
1033 show target-file-system-kind
1034 Set or show the assumed file system kind for target reported file
1037 save breakpoints <filename>
1038 Save all current breakpoint definitions to a file suitable for use
1039 in a later debugging session. To read the saved breakpoint
1040 definitions, use the `source' command.
1042 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1045 info static-tracepoint-markers
1046 Display information about static tracepoint markers in the target.
1048 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1049 Define a static tracepoint by probing a marker at the given
1050 function, line, address, or marker ID.
1054 Enable and disable observer mode.
1056 set may-write-registers on|off
1057 set may-write-memory on|off
1058 set may-insert-breakpoints on|off
1059 set may-insert-tracepoints on|off
1060 set may-insert-fast-tracepoints on|off
1061 set may-interrupt on|off
1062 Set individual permissions for GDB effects on the target. Note that
1063 some of these settings can have undesirable or surprising
1064 consequences, particularly when changed in the middle of a session.
1065 For instance, disabling the writing of memory can prevent
1066 breakpoints from being inserted, cause single-stepping to fail, or
1067 even crash your program, if you disable after breakpoints have been
1068 inserted. However, GDB should not crash.
1070 set record memory-query on|off
1071 show record memory-query
1072 Control whether to stop the inferior if memory changes caused
1073 by an instruction cannot be recorded.
1078 The disassemble command now supports "start,+length" form of two arguments.
1082 ** GDB now provides a new directory location, called the python directory,
1083 where Python scripts written for GDB can be installed. The location
1084 of that directory is <data-directory>/python, where <data-directory>
1085 is the GDB data directory. For more details, see section `Scripting
1086 GDB using Python' in the manual.
1088 ** The GDB Python API now has access to breakpoints, symbols, symbol
1089 tables, program spaces, inferiors, threads and frame's code blocks.
1090 Additionally, GDB Parameters can now be created from the API, and
1091 manipulated via set/show in the CLI.
1093 ** New functions gdb.target_charset, gdb.target_wide_charset,
1094 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1096 ** New exception gdb.GdbError.
1098 ** Pretty-printers are now also looked up in the current program space.
1100 ** Pretty-printers can now be individually enabled and disabled.
1102 ** GDB now looks for names of Python scripts to auto-load in a
1103 special section named `.debug_gdb_scripts', in addition to looking
1104 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1106 * Tracepoint actions were unified with breakpoint commands. In particular,
1107 there are no longer differences in "info break" output for breakpoints and
1108 tracepoints and the "commands" command can be used for both tracepoints and
1109 regular breakpoints.
1113 ARM Symbian arm*-*-symbianelf*
1115 * D language support.
1116 GDB now supports debugging programs written in the D programming
1119 * GDB now supports the extended ptrace interface for PowerPC which is
1120 available since Linux kernel version 2.6.34. This automatically enables
1121 any hardware breakpoints and additional hardware watchpoints available in
1122 the processor. The old ptrace interface exposes just one hardware
1123 watchpoint and no hardware breakpoints.
1125 * GDB is now able to use the Data Value Compare (DVC) register available on
1126 embedded PowerPC processors to implement in hardware simple watchpoint
1127 conditions of the form:
1129 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1131 This works in native GDB running on Linux kernels with the extended ptrace
1132 interface mentioned above.
1134 *** Changes in GDB 7.1
1138 ** Namespace Support
1140 GDB now supports importing of namespaces in C++. This enables the
1141 user to inspect variables from imported namespaces. Support for
1142 namepace aliasing has also been added. So, if a namespace is
1143 aliased in the current scope (e.g. namepace C=A; ) the user can
1144 print variables using the alias (e.g. (gdb) print C::x).
1148 All known bugs relating to the printing of virtual base class were
1149 fixed. It is now possible to call overloaded static methods using a
1154 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1155 and reinterpret_cast<> are now handled by the C++ expression parser.
1159 Xilinx MicroBlaze microblaze-*-*
1164 Xilinx MicroBlaze microblaze
1167 * Multi-program debugging.
1169 GDB now has support for multi-program (a.k.a. multi-executable or
1170 multi-exec) debugging. This allows for debugging multiple inferiors
1171 simultaneously each running a different program under the same GDB
1172 session. See "Debugging Multiple Inferiors and Programs" in the
1173 manual for more information. This implied some user visible changes
1174 in the multi-inferior support. For example, "info inferiors" now
1175 lists inferiors that are not running yet or that have exited
1176 already. See also "New commands" and "New options" below.
1178 * New tracing features
1180 GDB's tracepoint facility now includes several new features:
1182 ** Trace state variables
1184 GDB tracepoints now include support for trace state variables, which
1185 are variables managed by the target agent during a tracing
1186 experiment. They are useful for tracepoints that trigger each
1187 other, so for instance one tracepoint can count hits in a variable,
1188 and then a second tracepoint has a condition that is true when the
1189 count reaches a particular value. Trace state variables share the
1190 $-syntax of GDB convenience variables, and can appear in both
1191 tracepoint actions and condition expressions. Use the "tvariable"
1192 command to create, and "info tvariables" to view; see "Trace State
1193 Variables" in the manual for more detail.
1197 GDB now includes an option for defining fast tracepoints, which
1198 targets may implement more efficiently, such as by installing a jump
1199 into the target agent rather than a trap instruction. The resulting
1200 speedup can be by two orders of magnitude or more, although the
1201 tradeoff is that some program locations on some target architectures
1202 might not allow fast tracepoint installation, for instance if the
1203 instruction to be replaced is shorter than the jump. To request a
1204 fast tracepoint, use the "ftrace" command, with syntax identical to
1205 the regular trace command.
1207 ** Disconnected tracing
1209 It is now possible to detach GDB from the target while it is running
1210 a trace experiment, then reconnect later to see how the experiment
1211 is going. In addition, a new variable disconnected-tracing lets you
1212 tell the target agent whether to continue running a trace if the
1213 connection is lost unexpectedly.
1217 GDB now has the ability to save the trace buffer into a file, and
1218 then use that file as a target, similarly to you can do with
1219 corefiles. You can select trace frames, print data that was
1220 collected in them, and use tstatus to display the state of the
1221 tracing run at the moment that it was saved. To create a trace
1222 file, use "tsave <filename>", and to use it, do "target tfile
1225 ** Circular trace buffer
1227 You can ask the target agent to handle the trace buffer as a
1228 circular buffer, discarding the oldest trace frames to make room for
1229 newer ones, by setting circular-trace-buffer to on. This feature may
1230 not be available for all target agents.
1235 The disassemble command, when invoked with two arguments, now requires
1236 the arguments to be comma-separated.
1239 The info variables command now displays variable definitions. Files
1240 which only declare a variable are not shown.
1243 The source command is now capable of sourcing Python scripts.
1244 This feature is dependent on the debugger being build with Python
1247 Related to this enhancement is also the introduction of a new command
1248 "set script-extension" (see below).
1250 * New commands (for set/show, see "New options" below)
1252 record save [<FILENAME>]
1253 Save a file (in core file format) containing the process record
1254 execution log for replay debugging at a later time.
1256 record restore <FILENAME>
1257 Restore the process record execution log that was saved at an
1258 earlier time, for replay debugging.
1260 add-inferior [-copies <N>] [-exec <FILENAME>]
1263 clone-inferior [-copies <N>] [ID]
1264 Make a new inferior ready to execute the same program another
1265 inferior has loaded.
1270 maint info program-spaces
1271 List the program spaces loaded into GDB.
1273 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1274 show remote interrupt-sequence
1275 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1276 as the sequence to the remote target in order to interrupt the execution.
1277 Ctrl-C is a default. Some system prefers BREAK which is high level of
1278 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1279 Magic SysRq g. It is BREAK signal and character 'g'.
1281 set remote interrupt-on-connect [on | off]
1282 show remote interrupt-on-connect
1283 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1284 remote target when gdb connects to it. This is needed when you debug
1287 set remotebreak [on | off]
1289 Deprecated. Use "set/show remote interrupt-sequence" instead.
1291 tvariable $NAME [ = EXP ]
1292 Create or modify a trace state variable.
1295 List trace state variables and their values.
1297 delete tvariable $NAME ...
1298 Delete one or more trace state variables.
1301 Evaluate the given expressions without collecting anything into the
1302 trace buffer. (Valid in tracepoint actions only.)
1304 ftrace FN / FILE:LINE / *ADDR
1305 Define a fast tracepoint at the given function, line, or address.
1307 * New expression syntax
1309 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1310 GDB now parses 0b101010 identically with 42.
1314 set follow-exec-mode new|same
1315 show follow-exec-mode
1316 Control whether GDB reuses the same inferior across an exec call or
1317 creates a new one. This is useful to be able to restart the old
1318 executable after the inferior having done an exec call.
1320 set default-collect EXPR, ...
1321 show default-collect
1322 Define a list of expressions to be collected at each tracepoint.
1323 This is a useful way to ensure essential items are not overlooked,
1324 such as registers or a critical global variable.
1326 set disconnected-tracing
1327 show disconnected-tracing
1328 If set to 1, the target is instructed to continue tracing if it
1329 loses its connection to GDB. If 0, the target is to stop tracing
1332 set circular-trace-buffer
1333 show circular-trace-buffer
1334 If set to on, the target is instructed to use a circular trace buffer
1335 and discard the oldest trace frames instead of stopping the trace due
1336 to a full trace buffer. If set to off, the trace stops when the buffer
1337 fills up. Some targets may not support this.
1339 set script-extension off|soft|strict
1340 show script-extension
1341 If set to "off", the debugger does not perform any script language
1342 recognition, and all sourced files are assumed to be GDB scripts.
1343 If set to "soft" (the default), files are sourced according to
1344 filename extension, falling back to GDB scripts if the first
1346 If set to "strict", files are sourced according to filename extension.
1348 set ada trust-PAD-over-XVS on|off
1349 show ada trust-PAD-over-XVS
1350 If off, activate a workaround against a bug in the debugging information
1351 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1352 the GCC sources for more information about the GNAT encoding and
1353 PAD types in particular). It is always safe to set this option to
1354 off, but this introduces a slight performance penalty. The default
1357 * Python API Improvements
1359 ** GDB provides the new class gdb.LazyString. This is useful in
1360 some pretty-printing cases. The new method gdb.Value.lazy_string
1361 provides a simple way to create objects of this type.
1363 ** The fields returned by gdb.Type.fields now have an
1364 `is_base_class' attribute.
1366 ** The new method gdb.Type.range returns the range of an array type.
1368 ** The new method gdb.parse_and_eval can be used to parse and
1369 evaluate an expression.
1371 * New remote packets
1374 Define a trace state variable.
1377 Get the current value of a trace state variable.
1380 Set desired tracing behavior upon disconnection.
1383 Set the trace buffer to be linear or circular.
1386 Get data about the tracepoints currently in use.
1390 Process record now works correctly with hardware watchpoints.
1392 Multiple bug fixes have been made to the mips-irix port, making it
1393 much more reliable. In particular:
1394 - Debugging threaded applications is now possible again. Previously,
1395 GDB would hang while starting the program, or while waiting for
1396 the program to stop at a breakpoint.
1397 - Attaching to a running process no longer hangs.
1398 - An error occurring while loading a core file has been fixed.
1399 - Changing the value of the PC register now works again. This fixes
1400 problems observed when using the "jump" command, or when calling
1401 a function from GDB, or even when assigning a new value to $pc.
1402 - With the "finish" and "return" commands, the return value for functions
1403 returning a small array is now correctly printed.
1404 - It is now possible to break on shared library code which gets executed
1405 during a shared library init phase (code executed while executing
1406 their .init section). Previously, the breakpoint would have no effect.
1407 - GDB is now able to backtrace through the signal handler for
1408 non-threaded programs.
1410 PIE (Position Independent Executable) programs debugging is now supported.
1411 This includes debugging execution of PIC (Position Independent Code) shared
1412 libraries although for that, it should be possible to run such libraries as an
1415 *** Changes in GDB 7.0
1417 * GDB now has an interface for JIT compilation. Applications that
1418 dynamically generate code can create symbol files in memory and register
1419 them with GDB. For users, the feature should work transparently, and
1420 for JIT developers, the interface is documented in the GDB manual in the
1421 "JIT Compilation Interface" chapter.
1423 * Tracepoints may now be conditional. The syntax is as for
1424 breakpoints; either an "if" clause appended to the "trace" command,
1425 or the "condition" command is available. GDB sends the condition to
1426 the target for evaluation using the same bytecode format as is used
1427 for tracepoint actions.
1429 * The disassemble command now supports: an optional /r modifier, print the
1430 raw instructions in hex as well as in symbolic form, and an optional /m
1431 modifier to print mixed source+assembly.
1433 * Process record and replay
1435 In a architecture environment that supports ``process record and
1436 replay'', ``process record and replay'' target can record a log of
1437 the process execution, and replay it with both forward and reverse
1440 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1441 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1442 set execution-direction {forward|reverse}, for targets that support
1445 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1446 feature is available with a native GDB running on kernel version
1449 * GDB now has support for multi-byte and wide character sets on the
1450 target. Strings whose character type is wchar_t, char16_t, or
1451 char32_t are now correctly printed. GDB supports wide- and unicode-
1452 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1453 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1454 `printf'. This feature requires iconv to work properly; if your
1455 system does not have a working iconv, GDB can use GNU libiconv. See
1456 the installation instructions for more information.
1458 * GDB now supports automatic retrieval of shared library files from
1459 remote targets. To use this feature, specify a system root that begins
1460 with the `remote:' prefix, either via the `set sysroot' command or via
1461 the `--with-sysroot' configure-time option.
1463 * "info sharedlibrary" now takes an optional regex of libraries to show,
1464 and it now reports if a shared library has no debugging information.
1466 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1467 now complete on file names.
1469 * When completing in expressions, gdb will attempt to limit
1470 completions to allowable structure or union fields, where appropriate.
1471 For instance, consider:
1473 # struct example { int f1; double f2; };
1474 # struct example variable;
1477 If the user types TAB at the end of this command line, the available
1478 completions will be "f1" and "f2".
1480 * Inlined functions are now supported. They show up in backtraces, and
1481 the "step", "next", and "finish" commands handle them automatically.
1483 * GDB now supports the token-splicing (##) and stringification (#)
1484 operators when expanding macros. It also supports variable-arity
1487 * GDB now supports inspecting extra signal information, exported by
1488 the new $_siginfo convenience variable. The feature is currently
1489 implemented on linux ARM, i386 and amd64.
1491 * GDB can now display the VFP floating point registers and NEON vector
1492 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1493 can provide these registers (requires Linux 2.6.30 or later). Remote
1494 and simulator targets may also provide them.
1496 * New remote packets
1499 Search memory for a sequence of bytes.
1502 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1503 operation over reliable transport links. Use of this packet is
1504 controlled by the `set remote noack-packet' command.
1507 Kill the process with the specified process ID. Use this in preference
1508 to `k' when multiprocess protocol extensions are supported.
1511 Obtains additional operating system information
1515 Read or write additional signal information.
1517 * Removed remote protocol undocumented extension
1519 An undocumented extension to the remote protocol's `S' stop reply
1520 packet that permited the stub to pass a process id was removed.
1521 Remote servers should use the `T' stop reply packet instead.
1523 * GDB now supports multiple function calling conventions according to the
1524 DWARF-2 DW_AT_calling_convention function attribute.
1526 * The SH target utilizes the aforementioned change to distinguish between gcc
1527 and Renesas calling convention. It also adds the new CLI commands
1528 `set/show sh calling-convention'.
1530 * GDB can now read compressed debug sections, as produced by GNU gold
1531 with the --compress-debug-sections=zlib flag.
1533 * 64-bit core files are now supported on AIX.
1535 * Thread switching is now supported on Tru64.
1537 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1538 which will be allocated using malloc later in program execution.
1540 * The qXfer:libraries:read remote procotol packet now allows passing a
1541 list of section offsets.
1543 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1544 conditions handling signals delivered during attach or thread creation
1545 have also been fixed.
1547 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1548 From the user's standpoint, all unqualified instances of True and False
1549 are treated as the standard definitions, regardless of context.
1551 * GDB now parses C++ symbol and type names more flexibly. For
1554 template<typename T> class C { };
1557 GDB will now correctly handle all of:
1559 ptype C<char const *>
1560 ptype C<char const*>
1561 ptype C<const char *>
1562 ptype C<const char*>
1564 * New features in the GDB remote stub, gdbserver
1566 - The "--wrapper" command-line argument tells gdbserver to use a
1567 wrapper program to launch programs for debugging.
1569 - On PowerPC and S/390 targets, it is now possible to use a single
1570 gdbserver executable to debug both 32-bit and 64-bit programs.
1571 (This requires gdbserver itself to be built as a 64-bit executable.)
1573 - gdbserver uses the new noack protocol mode for TCP connections to
1574 reduce communications latency, if also supported and enabled in GDB.
1576 - Support for the sparc64-linux-gnu target is now included in
1579 - The amd64-linux build of gdbserver now supports debugging both
1580 32-bit and 64-bit programs.
1582 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1583 now support hardware watchpoints, and will use them automatically
1588 GDB now has support for scripting using Python. Whether this is
1589 available is determined at configure time.
1591 New GDB commands can now be written in Python.
1593 * Ada tasking support
1595 Ada tasks can now be inspected in GDB. The following commands have
1599 Print the list of Ada tasks.
1601 Print detailed information about task number N.
1603 Print the task number of the current task.
1605 Switch the context of debugging to task number N.
1607 * Support for user-defined prefixed commands. The "define" command can
1608 add new commands to existing prefixes, e.g. "target".
1610 * Multi-inferior, multi-process debugging.
1612 GDB now has generalized support for multi-inferior debugging. See
1613 "Debugging Multiple Inferiors" in the manual for more information.
1614 Although availability still depends on target support, the command
1615 set is more uniform now. The GNU/Linux specific multi-forks support
1616 has been migrated to this new framework. This implied some user
1617 visible changes; see "New commands" and also "Removed commands"
1620 * Target descriptions can now describe the target OS ABI. See the
1621 "Target Description Format" section in the user manual for more
1624 * Target descriptions can now describe "compatible" architectures
1625 to indicate that the target can execute applications for a different
1626 architecture in addition to those for the main target architecture.
1627 See the "Target Description Format" section in the user manual for
1630 * Multi-architecture debugging.
1632 GDB now includes general supports for debugging applications on
1633 hybrid systems that use more than one single processor architecture
1634 at the same time. Each such hybrid architecture still requires
1635 specific support to be added. The only hybrid architecture supported
1636 in this version of GDB is the Cell Broadband Engine.
1638 * GDB now supports integrated debugging of Cell/B.E. applications that
1639 use both the PPU and SPU architectures. To enable support for hybrid
1640 Cell/B.E. debugging, you need to configure GDB to support both the
1641 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1642 --enable-targets configure option.
1644 * Non-stop mode debugging.
1646 For some targets, GDB now supports an optional mode of operation in
1647 which you can examine stopped threads while other threads continue
1648 to execute freely. This is referred to as non-stop mode, with the
1649 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1650 section in the user manual for more information.
1652 To be able to support remote non-stop debugging, a remote stub needs
1653 to implement the non-stop mode remote protocol extensions, as
1654 described in the "Remote Non-Stop" section of the user manual. The
1655 GDB remote stub, gdbserver, has been adjusted to support these
1656 extensions on linux targets.
1658 * New commands (for set/show, see "New options" below)
1660 catch syscall [NAME(S) | NUMBER(S)]
1661 Catch system calls. Arguments, which should be names of system
1662 calls or their numbers, mean catch only those syscalls. Without
1663 arguments, every syscall will be caught. When the inferior issues
1664 any of the specified syscalls, GDB will stop and announce the system
1665 call, both when it is called and when its call returns. This
1666 feature is currently available with a native GDB running on the
1667 Linux Kernel, under the following architectures: x86, x86_64,
1668 PowerPC and PowerPC64.
1670 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1672 Search memory for a sequence of bytes.
1674 maint set python print-stack
1675 maint show python print-stack
1676 Show a stack trace when an error is encountered in a Python script.
1679 Invoke CODE by passing it to the Python interpreter.
1684 These allow macros to be defined, undefined, and listed
1688 Show operating system information about processes.
1691 List the inferiors currently under GDB's control.
1694 Switch focus to inferior number NUM.
1697 Detach from inferior number NUM.
1700 Kill inferior number NUM.
1704 set spu stop-on-load
1705 show spu stop-on-load
1706 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1708 set spu auto-flush-cache
1709 show spu auto-flush-cache
1710 Control whether to automatically flush the software-managed cache
1711 during Cell/B.E. debugging.
1713 set sh calling-convention
1714 show sh calling-convention
1715 Control the calling convention used when calling SH target functions.
1718 show debug timestamp
1719 Control display of timestamps with GDB debugging output.
1721 set disassemble-next-line
1722 show disassemble-next-line
1723 Control display of disassembled source lines or instructions when
1726 set remote noack-packet
1727 show remote noack-packet
1728 Set/show the use of remote protocol QStartNoAckMode packet. See above
1729 under "New remote packets."
1731 set remote query-attached-packet
1732 show remote query-attached-packet
1733 Control use of remote protocol `qAttached' (query-attached) packet.
1735 set remote read-siginfo-object
1736 show remote read-siginfo-object
1737 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1740 set remote write-siginfo-object
1741 show remote write-siginfo-object
1742 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1745 set remote reverse-continue
1746 show remote reverse-continue
1747 Control use of remote protocol 'bc' (reverse-continue) packet.
1749 set remote reverse-step
1750 show remote reverse-step
1751 Control use of remote protocol 'bs' (reverse-step) packet.
1753 set displaced-stepping
1754 show displaced-stepping
1755 Control displaced stepping mode. Displaced stepping is a way to
1756 single-step over breakpoints without removing them from the debuggee.
1757 Also known as "out-of-line single-stepping".
1760 show debug displaced
1761 Control display of debugging info for displaced stepping.
1763 maint set internal-error
1764 maint show internal-error
1765 Control what GDB does when an internal error is detected.
1767 maint set internal-warning
1768 maint show internal-warning
1769 Control what GDB does when an internal warning is detected.
1774 Use a wrapper program to launch programs for debugging.
1776 set multiple-symbols (all|ask|cancel)
1777 show multiple-symbols
1778 The value of this variable can be changed to adjust the debugger behavior
1779 when an expression or a breakpoint location contains an ambiguous symbol
1780 name (an overloaded function name, for instance).
1782 set breakpoint always-inserted
1783 show breakpoint always-inserted
1784 Keep breakpoints always inserted in the target, as opposed to inserting
1785 them when resuming the target, and removing them when the target stops.
1786 This option can improve debugger performance on slow remote targets.
1788 set arm fallback-mode (arm|thumb|auto)
1789 show arm fallback-mode
1790 set arm force-mode (arm|thumb|auto)
1792 These commands control how ARM GDB determines whether instructions
1793 are ARM or Thumb. The default for both settings is auto, which uses
1794 the current CPSR value for instructions without symbols; previous
1795 versions of GDB behaved as if "set arm fallback-mode arm".
1797 set disable-randomization
1798 show disable-randomization
1799 Standalone programs run with the virtual address space randomization enabled
1800 by default on some platforms. This option keeps the addresses stable across
1801 multiple debugging sessions.
1805 Control whether other threads are stopped or not when some thread hits
1810 Requests that asynchronous execution is enabled in the target, if available.
1811 In this case, it's possible to resume target in the background, and interact
1812 with GDB while the target is running. "show target-async" displays the
1813 current state of asynchronous execution of the target.
1815 set target-wide-charset
1816 show target-wide-charset
1817 The target-wide-charset is the name of the character set that GDB
1818 uses when printing characters whose type is wchar_t.
1820 set tcp auto-retry (on|off)
1822 set tcp connect-timeout
1823 show tcp connect-timeout
1824 These commands allow GDB to retry failed TCP connections to a remote stub
1825 with a specified timeout period; this is useful if the stub is launched
1826 in parallel with GDB but may not be ready to accept connections immediately.
1828 set libthread-db-search-path
1829 show libthread-db-search-path
1830 Control list of directories which GDB will search for appropriate
1833 set schedule-multiple (on|off)
1834 show schedule-multiple
1835 Allow GDB to resume all threads of all processes or only threads of
1836 the current process.
1840 Use more aggressive caching for accesses to the stack. This improves
1841 performance of remote debugging (particularly backtraces) without
1842 affecting correctness.
1844 set interactive-mode (on|off|auto)
1845 show interactive-mode
1846 Control whether GDB runs in interactive mode (on) or not (off).
1847 When in interactive mode, GDB waits for the user to answer all
1848 queries. Otherwise, GDB does not wait and assumes the default
1849 answer. When set to auto (the default), GDB determines which
1850 mode to use based on the stdin settings.
1855 For program forks, this is replaced by the new more generic `info
1856 inferiors' command. To list checkpoints, you can still use the
1857 `info checkpoints' command, which was an alias for the `info forks'
1861 Replaced by the new `inferior' command. To switch between
1862 checkpoints, you can still use the `restart' command, which was an
1863 alias for the `fork' command.
1866 This is removed, since some targets don't have a notion of
1867 processes. To switch between processes, you can still use the
1868 `inferior' command using GDB's own inferior number.
1871 For program forks, this is replaced by the new more generic `kill
1872 inferior' command. To delete a checkpoint, you can still use the
1873 `delete checkpoint' command, which was an alias for the `delete
1877 For program forks, this is replaced by the new more generic `detach
1878 inferior' command. To detach a checkpoint, you can still use the
1879 `detach checkpoint' command, which was an alias for the `detach
1882 * New native configurations
1884 x86/x86_64 Darwin i[34567]86-*-darwin*
1886 x86_64 MinGW x86_64-*-mingw*
1890 Lattice Mico32 lm32-*
1891 x86 DICOS i[34567]86-*-dicos*
1892 x86_64 DICOS x86_64-*-dicos*
1895 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1896 (mingw32ce) debugging.
1902 These commands were actually not implemented on any target.
1904 *** Changes in GDB 6.8
1906 * New native configurations
1908 NetBSD/hppa hppa*-*netbsd*
1909 Xtensa GNU/Linux xtensa*-*-linux*
1913 NetBSD/hppa hppa*-*-netbsd*
1914 Xtensa GNU/Lunux xtensa*-*-linux*
1916 * Change in command line behavior -- corefiles vs. process ids.
1918 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1919 attaching to process NUMBER fails, GDB no longer attempts to open a
1920 core file named NUMBER. Attaching to a program using the -c option
1921 is no longer supported. Instead, use the '-p' or '--pid' options.
1923 * GDB can now be built as a native debugger for debugging Windows x86
1924 (mingw32) Portable Executable (PE) programs.
1926 * Pending breakpoints no longer change their number when their address
1929 * GDB now supports breakpoints with multiple locations,
1930 including breakpoints on C++ constructors, inside C++ templates,
1931 and in inlined functions.
1933 * GDB's ability to debug optimized code has been improved. GDB more
1934 accurately identifies function bodies and lexical blocks that occupy
1935 more than one contiguous range of addresses.
1937 * Target descriptions can now describe registers for PowerPC.
1939 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1940 registers on PowerPC targets.
1942 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1943 targets even when the libthread_db library is not available.
1945 * The GDB remote stub, gdbserver, now supports the new file transfer
1946 commands (remote put, remote get, and remote delete).
1948 * The GDB remote stub, gdbserver, now supports run and attach in
1949 extended-remote mode.
1951 * hppa*64*-*-hpux11* target broken
1952 The debugger is unable to start a program and fails with the following
1953 error: "Error trying to get information about dynamic linker".
1954 The gdb-6.7 release is also affected.
1956 * GDB now supports the --enable-targets= configure option to allow
1957 building a single GDB executable that supports multiple remote
1958 target architectures.
1960 * GDB now supports debugging C and C++ programs which use the
1961 Decimal Floating Point extension. In addition, the PowerPC target
1962 now has a set of pseudo-registers to inspect decimal float values
1963 stored in two consecutive float registers.
1965 * The -break-insert MI command can optionally create pending
1968 * Improved support for debugging Ada
1969 Many improvements to the Ada language support have been made. These
1971 - Better support for Ada2005 interface types
1972 - Improved handling of arrays and slices in general
1973 - Better support for Taft-amendment types
1974 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1976 - Improved command completion in Ada
1979 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1984 set print frame-arguments (all|scalars|none)
1985 show print frame-arguments
1986 The value of this variable can be changed to control which argument
1987 values should be printed by the debugger when displaying a frame.
1992 Transfer files to and from a remote target, and delete remote files.
1999 Transfer files to and from a remote target, and delete remote files.
2001 * New remote packets
2008 Open, close, read, write, and delete files on the remote system.
2011 Attach to an existing process on the remote system, in extended-remote
2015 Run a new process on the remote system, in extended-remote mode.
2017 *** Changes in GDB 6.7
2019 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2020 bfd, libiberty and opcodes, as revealed by static analysis donated by
2021 Coverity, Inc. (http://scan.coverity.com).
2023 * When looking up multiply-defined global symbols, GDB will now prefer the
2024 symbol definition in the current shared library if it was built using the
2025 -Bsymbolic linker option.
2027 * When the Text User Interface (TUI) is not configured, GDB will now
2028 recognize the -tui command-line option and print a message that the TUI
2031 * The GDB remote stub, gdbserver, now has lower overhead for high
2032 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2034 * GDB for MIPS targets now autodetects whether a remote target provides
2035 32-bit or 64-bit register values.
2037 * Support for C++ member pointers has been improved.
2039 * GDB now understands XML target descriptions, which specify the
2040 target's overall architecture. GDB can read a description from
2041 a local file or over the remote serial protocol.
2043 * Vectors of single-byte data use a new integer type which is not
2044 automatically displayed as character or string data.
2046 * The /s format now works with the print command. It displays
2047 arrays of single-byte integers and pointers to single-byte integers
2050 * Target descriptions can now describe target-specific registers,
2051 for architectures which have implemented the support (currently
2052 only ARM, M68K, and MIPS).
2054 * GDB and the GDB remote stub, gdbserver, now support the XScale
2057 * The GDB remote stub, gdbserver, has been updated to support
2058 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2059 has been rewritten to use the standard GDB remote protocol.
2061 * GDB can now step into C++ functions which are called through thunks.
2063 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2065 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2066 layout. It also supports a TextSeg= and DataSeg= response when only
2067 segment base addresses (rather than offsets) are available.
2069 * The /i format now outputs any trailing branch delay slot instructions
2070 immediately following the last instruction within the count specified.
2072 * The GDB remote protocol "T" stop reply packet now supports a
2073 "library" response. Combined with the new "qXfer:libraries:read"
2074 packet, this response allows GDB to debug shared libraries on targets
2075 where the operating system manages the list of loaded libraries (e.g.
2076 Windows and SymbianOS).
2078 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2079 (DLLs) on Windows and Windows CE targets.
2081 * GDB now supports a faster verification that a .debug file matches its binary
2082 according to its build-id signature, if the signature is present.
2088 Enable or disable hardware flow control (RTS/CTS) on the serial port
2089 when debugging using remote targets.
2091 set mem inaccessible-by-default
2092 show mem inaccessible-by-default
2093 If the target supplies a memory map, for instance via the remote
2094 protocol's "qXfer:memory-map:read" packet, setting this variable
2095 prevents GDB from accessing memory outside the memory map. This
2096 is useful for targets with memory mapped registers or which react
2097 badly to accesses of unmapped address space.
2099 set breakpoint auto-hw
2100 show breakpoint auto-hw
2101 If the target supplies a memory map, for instance via the remote
2102 protocol's "qXfer:memory-map:read" packet, setting this variable
2103 lets GDB use hardware breakpoints automatically for memory regions
2104 where it can not use software breakpoints. This covers both the
2105 "break" command and internal breakpoints used for other commands
2106 including "next" and "finish".
2109 catch exception unhandled
2110 Stop the program execution when Ada exceptions are raised.
2113 Stop the program execution when an Ada assertion failed.
2117 Set an alternate system root for target files. This is a more
2118 general version of "set solib-absolute-prefix", which is now
2119 an alias to "set sysroot".
2122 Provide extended SPU facility status information. This set of
2123 commands is available only when debugging the Cell/B.E. SPU
2126 * New native configurations
2128 OpenBSD/sh sh*-*openbsd*
2131 unset tdesc filename
2133 Use the specified local file as an XML target description, and do
2134 not query the target for its built-in description.
2138 OpenBSD/sh sh*-*-openbsd*
2139 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2140 Toshiba Media Processor mep-elf
2142 * New remote packets
2145 Ignore the specified signals; pass them directly to the debugged program
2146 without stopping other threads or reporting them to GDB.
2148 qXfer:features:read:
2149 Read an XML target description from the target, which describes its
2154 Read or write contents of an spufs file on the target system. These
2155 packets are available only on the Cell/B.E. SPU architecture.
2157 qXfer:libraries:read:
2158 Report the loaded shared libraries. Combined with new "T" packet
2159 response, this packet allows GDB to debug shared libraries on
2160 targets where the operating system manages the list of loaded
2161 libraries (e.g. Windows and SymbianOS).
2165 Support for these obsolete configurations has been removed.
2173 i[34567]86-*-lynxos*
2174 i[34567]86-*-netware*
2175 i[34567]86-*-sco3.2v5*
2176 i[34567]86-*-sco3.2v4*
2178 i[34567]86-*-sysv4.2*
2181 i[34567]86-*-unixware2*
2182 i[34567]86-*-unixware*
2191 * Other removed features
2198 Various m68k-only ROM monitors.
2205 Various Renesas ROM monitors and debugging interfaces for SH and
2210 Support for a Macraigor serial interface to on-chip debugging.
2211 GDB does not directly support the newer parallel or USB
2216 A debug information format. The predecessor to DWARF 2 and
2217 DWARF 3, which are still supported.
2219 Support for the HP aCC compiler on HP-UX/PA-RISC
2221 SOM-encapsulated symbolic debugging information, automatic
2222 invocation of pxdb, and the aCC custom C++ ABI. This does not
2223 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2224 with aCC can still be debugged on an assembly level.
2226 MIPS ".pdr" sections
2228 A MIPS-specific format used to describe stack frame layout
2229 in debugging information.
2233 GDB could work with an older version of Guile to debug
2234 the interpreter and Scheme programs running in it.
2236 set mips stack-arg-size
2237 set mips saved-gpreg-size
2239 Use "set mips abi" to control parameter passing for MIPS.
2241 *** Changes in GDB 6.6
2246 Cell Broadband Engine SPU spu-elf
2248 * GDB can now be configured as a cross-debugger targeting native Windows
2249 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2250 running on a Windows system over TCP/IP to debug Windows programs.
2252 * The GDB remote stub, gdbserver, has been updated to support Windows and
2253 Cygwin debugging. Both single-threaded and multi-threaded programs are
2256 * The "set trust-readonly-sections" command works again. This command was
2257 broken in GDB 6.3, 6.4, and 6.5.
2259 * The "load" command now supports writing to flash memory, if the remote
2260 stub provides the required support.
2262 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2263 longer requires symbolic debug information (e.g. DWARF-2).
2268 unset substitute-path
2269 show substitute-path
2270 Manage a list of substitution rules that GDB uses to rewrite the name
2271 of the directories where the sources are located. This can be useful
2272 for instance when the sources were moved to a different location
2273 between compilation and debugging.
2277 Print each CLI command as it is executed. Each command is prefixed with
2278 a number of `+' symbols representing the nesting depth.
2279 The source command now has a `-v' option to enable the same feature.
2283 The ARM Demon monitor support (RDP protocol, "target rdp").
2285 Kernel Object Display, an embedded debugging feature which only worked with
2286 an obsolete version of Cisco IOS.
2288 The 'set download-write-size' and 'show download-write-size' commands.
2290 * New remote packets
2293 Tell a stub about GDB client features, and request remote target features.
2294 The first feature implemented is PacketSize, which allows the target to
2295 specify the size of packets it can handle - to minimize the number of
2296 packets required and improve performance when connected to a remote
2300 Fetch an OS auxilliary vector from the remote stub. This packet is a
2301 more efficient replacement for qPart:auxv:read.
2303 qXfer:memory-map:read:
2304 Fetch a memory map from the remote stub, including information about
2305 RAM, ROM, and flash memory devices.
2310 Erase and program a flash memory device.
2312 * Removed remote packets
2315 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2316 used it, and only gdbserver implemented it.
2318 *** Changes in GDB 6.5
2322 Renesas M32C/M16C m32c-elf
2324 Morpho Technologies ms1 ms1-elf
2328 init-if-undefined Initialize a convenience variable, but
2329 only if it doesn't already have a value.
2331 The following commands are presently only implemented for native GNU/Linux:
2333 checkpoint Save a snapshot of the program state.
2335 restart <n> Return the program state to a
2336 previously saved state.
2338 info checkpoints List currently saved checkpoints.
2340 delete-checkpoint <n> Delete a previously saved checkpoint.
2342 set|show detach-on-fork Tell gdb whether to detach from a newly
2343 forked process, or to keep debugging it.
2345 info forks List forks of the user program that
2346 are available to be debugged.
2348 fork <n> Switch to debugging one of several
2349 forks of the user program that are
2350 available to be debugged.
2352 delete-fork <n> Delete a fork from the list of forks
2353 that are available to be debugged (and
2354 kill the forked process).
2356 detach-fork <n> Delete a fork from the list of forks
2357 that are available to be debugged (and
2358 allow the process to continue).
2362 Morpho Technologies ms2 ms1-elf
2364 * Improved Windows host support
2366 GDB now builds as a cross debugger hosted on i686-mingw32, including
2367 native console support, and remote communications using either
2368 network sockets or serial ports.
2370 * Improved Modula-2 language support
2372 GDB can now print most types in the Modula-2 syntax. This includes:
2373 basic types, set types, record types, enumerated types, range types,
2374 pointer types and ARRAY types. Procedure var parameters are correctly
2375 printed and hexadecimal addresses and character constants are also
2376 written in the Modula-2 syntax. Best results can be obtained by using
2377 GNU Modula-2 together with the -gdwarf-2 command line option.
2381 The ARM rdi-share module.
2383 The Netware NLM debug server.
2385 *** Changes in GDB 6.4
2387 * New native configurations
2389 OpenBSD/arm arm*-*-openbsd*
2390 OpenBSD/mips64 mips64-*-openbsd*
2394 Morpho Technologies ms1 ms1-elf
2396 * New command line options
2398 --batch-silent As for --batch, but totally silent.
2399 --return-child-result The debugger will exist with the same value
2400 the child (debugged) program exited with.
2401 --eval-command COMMAND, -ex COMMAND
2402 Execute a single GDB CLI command. This may be
2403 specified multiple times and in conjunction
2404 with the --command (-x) option.
2406 * Deprecated commands removed
2408 The following commands, that were deprecated in 2000, have been
2412 set|show arm disassembly-flavor set|show arm disassembler
2413 othernames set arm disassembler
2414 set|show remotedebug set|show debug remote
2415 set|show archdebug set|show debug arch
2416 set|show eventdebug set|show debug event
2419 * New BSD user-level threads support
2421 It is now possible to debug programs using the user-level threads
2422 library on OpenBSD and FreeBSD. Currently supported (target)
2425 FreeBSD/amd64 x86_64-*-freebsd*
2426 FreeBSD/i386 i386-*-freebsd*
2427 OpenBSD/i386 i386-*-openbsd*
2429 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2430 are not yet supported.
2432 * New support for Matsushita MN10300 w/sim added
2433 (Work in progress). mn10300-elf.
2435 * REMOVED configurations and files
2437 VxWorks and the XDR protocol *-*-vxworks
2438 Motorola MCORE mcore-*-*
2439 National Semiconductor NS32000 ns32k-*-*
2441 * New "set print array-indexes" command
2443 After turning this setting "on", GDB prints the index of each element
2444 when displaying arrays. The default is "off" to preserve the previous
2447 * VAX floating point support
2449 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2451 * User-defined command support
2453 In addition to using $arg0..$arg9 for argument passing, it is now possible
2454 to use $argc to determine now many arguments have been passed. See the
2455 section on user-defined commands in the user manual for more information.
2457 *** Changes in GDB 6.3:
2459 * New command line option
2461 GDB now accepts -l followed by a number to set the timeout for remote
2464 * GDB works with GCC -feliminate-dwarf2-dups
2466 GDB now supports a more compact representation of DWARF-2 debug
2467 information using DW_FORM_ref_addr references. These are produced
2468 by GCC with the option -feliminate-dwarf2-dups and also by some
2469 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2470 to use -feliminate-dwarf2-dups.
2472 * Internationalization
2474 When supported by the host system, GDB will be built with
2475 internationalization (libintl). The task of marking up the sources is
2476 continued, we're looking forward to our first translation.
2480 Initial support for debugging programs compiled with the GNAT
2481 implementation of the Ada programming language has been integrated
2482 into GDB. In this release, support is limited to expression evaluation.
2484 * New native configurations
2486 GNU/Linux/m32r m32r-*-linux-gnu
2490 GDB's remote protocol now includes support for the 'p' packet. This
2491 packet is used to fetch individual registers from a remote inferior.
2493 * END-OF-LIFE registers[] compatibility module
2495 GDB's internal register infrastructure has been completely rewritten.
2496 The new infrastructure making possible the implementation of key new
2497 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2500 GDB 6.3 will be the last release to include the the registers[]
2501 compatibility module that allowed out-of-date configurations to
2502 continue to work. This change directly impacts the following
2512 powerpc bdm protocol
2514 Unless there is activity to revive these configurations, they will be
2515 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2517 * OBSOLETE configurations and files
2519 Configurations that have been declared obsolete in this release have
2520 been commented out. Unless there is activity to revive these
2521 configurations, the next release of GDB will have their sources
2522 permanently REMOVED.
2531 *** Changes in GDB 6.2.1:
2533 * MIPS `break main; run' gave an heuristic-fence-post warning
2535 When attempting to run even a simple program, a warning about
2536 heuristic-fence-post being hit would be reported. This problem has
2539 * MIPS IRIX 'long double' crashed GDB
2541 When examining a long double variable, GDB would get a segmentation
2542 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2543 IRIX long double values).
2547 A bug in the VAX stack code was causing problems with the "next"
2548 command. This problem has been fixed.
2550 *** Changes in GDB 6.2:
2552 * Fix for ``many threads''
2554 On GNU/Linux systems that use the NPTL threads library, a program
2555 rapidly creating and deleting threads would confuse GDB leading to the
2558 ptrace: No such process.
2559 thread_db_get_info: cannot get thread info: generic error
2561 This problem has been fixed.
2563 * "-async" and "-noasync" options removed.
2565 Support for the broken "-noasync" option has been removed (it caused
2568 * New ``start'' command.
2570 This command runs the program until the begining of the main procedure.
2572 * New BSD Kernel Data Access Library (libkvm) interface
2574 Using ``target kvm'' it is now possible to debug kernel core dumps and
2575 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2576 platforms. Currently supported (native-only) configurations are:
2578 FreeBSD/amd64 x86_64-*-freebsd*
2579 FreeBSD/i386 i?86-*-freebsd*
2580 NetBSD/i386 i?86-*-netbsd*
2581 NetBSD/m68k m68*-*-netbsd*
2582 NetBSD/sparc sparc-*-netbsd*
2583 OpenBSD/amd64 x86_64-*-openbsd*
2584 OpenBSD/i386 i?86-*-openbsd*
2585 OpenBSD/m68k m68*-openbsd*
2586 OpenBSD/sparc sparc-*-openbsd*
2588 * Signal trampoline code overhauled
2590 Many generic problems with GDB's signal handling code have been fixed.
2591 These include: backtraces through non-contiguous stacks; recognition
2592 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2593 call; backtrace through a signal trampoline; step into and out of
2594 signal handlers; and single-stepping in the signal trampoline.
2596 Please note that kernel bugs are a limiting factor here. These
2597 features have been shown to work on an s390 GNU/Linux system that
2598 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2600 * Cygwin support for DWARF 2 added.
2602 * New native configurations
2604 GNU/Linux/hppa hppa*-*-linux*
2605 OpenBSD/hppa hppa*-*-openbsd*
2606 OpenBSD/m68k m68*-*-openbsd*
2607 OpenBSD/m88k m88*-*-openbsd*
2608 OpenBSD/powerpc powerpc-*-openbsd*
2609 NetBSD/vax vax-*-netbsd*
2610 OpenBSD/vax vax-*-openbsd*
2612 * END-OF-LIFE frame compatibility module
2614 GDB's internal frame infrastructure has been completely rewritten.
2615 The new infrastructure making it possible to support key new features
2616 including DWARF 2 Call Frame Information. To aid in the task of
2617 migrating old configurations to this new infrastructure, a
2618 compatibility module, that allowed old configurations to continue to
2619 work, was also included.
2621 GDB 6.2 will be the last release to include this frame compatibility
2622 module. This change directly impacts the following configurations:
2632 Unless there is activity to revive these configurations, they will be
2633 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2635 * REMOVED configurations and files
2637 Sun 3, running SunOS 3 m68*-*-sunos3*
2638 Sun 3, running SunOS 4 m68*-*-sunos4*
2639 Sun 2, running SunOS 3 m68000-*-sunos3*
2640 Sun 2, running SunOS 4 m68000-*-sunos4*
2641 Motorola 680x0 running LynxOS m68*-*-lynxos*
2642 AT&T 3b1/Unix pc m68*-att-*
2643 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2644 decstation mips-dec-* mips-little-*
2645 riscos mips-*-riscos* mips-*-sysv*
2646 sonymips mips-sony-*
2647 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2649 *** Changes in GDB 6.1.1:
2651 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2653 The TUI (Text-mode User Interface) is now built as part of a default
2654 GDB configuration. It is enabled by either selecting the TUI with the
2655 command line option "-i=tui" or by running the separate "gdbtui"
2656 program. For more information on the TUI, see the manual "Debugging
2659 * Pending breakpoint support (also included in GDB 6.1)
2661 Support has been added to allow you to specify breakpoints in shared
2662 libraries that have not yet been loaded. If a breakpoint location
2663 cannot be found, and the "breakpoint pending" option is set to auto,
2664 GDB queries you if you wish to make the breakpoint pending on a future
2665 shared-library load. If and when GDB resolves the breakpoint symbol,
2666 the pending breakpoint is removed as one or more regular breakpoints
2669 Pending breakpoints are very useful for GCJ Java debugging.
2671 * Fixed ISO-C build problems
2673 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2674 non ISO-C code that stopped them being built using a more strict ISO-C
2675 compiler (e.g., IBM's C compiler).
2677 * Fixed build problem on IRIX 5
2679 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2680 wasn't able to compile compile on an IRIX 5 system.
2682 * Added execute permission to gdb/gdbserver/configure
2684 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2685 permission. This bug would cause configure to fail on a number of
2686 systems (Solaris, IRIX). Ref: server/519.
2688 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2690 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2691 has been updated to use constant array sizes.
2693 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2695 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2696 its generated DWARF Call Frame Info. This encoding was causing GDB to
2697 panic, that panic has been fixed. Ref: gdb/1628.
2699 * Fixed a problem when examining parameters in shared library code.
2701 When examining parameters in optimized shared library code generated
2702 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2703 not available''. GDB now correctly displays the variable's value.
2705 *** Changes in GDB 6.1:
2707 * Removed --with-mmalloc
2709 Support for the mmalloc memory manager has been removed, as it
2710 conflicted with the internal gdb byte cache.
2712 * Changes in AMD64 configurations
2714 The AMD64 target now includes the %cs and %ss registers. As a result
2715 the AMD64 remote protocol has changed; this affects the floating-point
2716 and SSE registers. If you rely on those registers for your debugging,
2717 you should upgrade gdbserver on the remote side.
2719 * Revised SPARC target
2721 The SPARC target has been completely revised, incorporating the
2722 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2723 support for LynxOS and SunOS 4 has been dropped. Calling functions
2724 from within GDB on operating systems with a non-executable stack
2725 (Solaris, OpenBSD) now works.
2729 GDB has a new C++ demangler which does a better job on the mangled
2730 names generated by current versions of g++. It also runs faster, so
2731 with this and other changes gdb should now start faster on large C++
2734 * DWARF 2 Location Expressions
2736 GDB support for location expressions has been extended to support function
2737 arguments and frame bases. Older versions of GDB could crash when they
2740 * C++ nested types and namespaces
2742 GDB's support for nested types and namespaces in C++ has been
2743 improved, especially if you use the DWARF 2 debugging format. (This
2744 is the default for recent versions of GCC on most platforms.)
2745 Specifically, if you have a class "Inner" defined within a class or
2746 namespace "Outer", then GDB realizes that the class's name is
2747 "Outer::Inner", not simply "Inner". This should greatly reduce the
2748 frequency of complaints about not finding RTTI symbols. In addition,
2749 if you are stopped at inside of a function defined within a namespace,
2750 GDB modifies its name lookup accordingly.
2752 * New native configurations
2754 NetBSD/amd64 x86_64-*-netbsd*
2755 OpenBSD/amd64 x86_64-*-openbsd*
2756 OpenBSD/alpha alpha*-*-openbsd*
2757 OpenBSD/sparc sparc-*-openbsd*
2758 OpenBSD/sparc64 sparc64-*-openbsd*
2760 * New debugging protocols
2762 M32R with SDI protocol m32r-*-elf*
2764 * "set prompt-escape-char" command deleted.
2766 The command "set prompt-escape-char" has been deleted. This command,
2767 and its very obscure effet on GDB's prompt, was never documented,
2768 tested, nor mentioned in the NEWS file.
2770 * OBSOLETE configurations and files
2772 Configurations that have been declared obsolete in this release have
2773 been commented out. Unless there is activity to revive these
2774 configurations, the next release of GDB will have their sources
2775 permanently REMOVED.
2777 Sun 3, running SunOS 3 m68*-*-sunos3*
2778 Sun 3, running SunOS 4 m68*-*-sunos4*
2779 Sun 2, running SunOS 3 m68000-*-sunos3*
2780 Sun 2, running SunOS 4 m68000-*-sunos4*
2781 Motorola 680x0 running LynxOS m68*-*-lynxos*
2782 AT&T 3b1/Unix pc m68*-att-*
2783 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2784 decstation mips-dec-* mips-little-*
2785 riscos mips-*-riscos* mips-*-sysv*
2786 sonymips mips-sony-*
2787 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2789 * REMOVED configurations and files
2791 SGI Irix-4.x mips-sgi-irix4 or iris4
2792 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2793 Z8000 simulator z8k-zilog-none or z8ksim
2794 Matsushita MN10200 w/simulator mn10200-*-*
2795 H8/500 simulator h8500-hitachi-hms or h8500hms
2796 HP/PA running BSD hppa*-*-bsd*
2797 HP/PA running OSF/1 hppa*-*-osf*
2798 HP/PA Pro target hppa*-*-pro*
2799 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2800 386BSD i[3456]86-*-bsd*
2801 Sequent family i[3456]86-sequent-sysv4*
2802 i[3456]86-sequent-sysv*
2803 i[3456]86-sequent-bsd*
2804 SPARC running LynxOS sparc-*-lynxos*
2805 SPARC running SunOS 4 sparc-*-sunos4*
2806 Tsqware Sparclet sparclet-*-*
2807 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2809 *** Changes in GDB 6.0:
2813 Support for debugging the Objective-C programming language has been
2814 integrated into GDB.
2816 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2818 DWARF 2's Call Frame Information makes available compiler generated
2819 information that more exactly describes the program's run-time stack.
2820 By using this information, GDB is able to provide more robust stack
2823 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2824 have been updated to use a new backtrace mechanism which includes
2825 DWARF 2 CFI support.
2829 GDB's remote protocol has been extended to include support for hosted
2830 file I/O (where the remote target uses GDB's file system). See GDB's
2831 remote protocol documentation for details.
2833 * All targets using the new architecture framework.
2835 All of GDB's targets have been updated to use the new internal
2836 architecture framework. The way is now open for future GDB releases
2837 to include cross-architecture native debugging support (i386 on amd64,
2840 * GNU/Linux's Thread Local Storage (TLS)
2842 GDB now includes support for for the GNU/Linux implementation of
2843 per-thread variables.
2845 * GNU/Linux's Native POSIX Thread Library (NPTL)
2847 GDB's thread code has been updated to work with either the new
2848 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2850 * Separate debug info.
2852 GDB, in conjunction with BINUTILS, now supports a mechanism for
2853 automatically loading debug information from a separate file. Instead
2854 of shipping full debug and non-debug versions of system libraries,
2855 system integrators can now instead ship just the stripped libraries
2856 and optional debug files.
2858 * DWARF 2 Location Expressions
2860 DWARF 2 Location Expressions allow the compiler to more completely
2861 describe the location of variables (even in optimized code) to the
2864 GDB now includes preliminary support for location expressions (support
2865 for DW_OP_piece is still missing).
2869 A number of long standing bugs that caused GDB to die while starting a
2870 Java application have been fixed. GDB's Java support is now
2871 considered "useable".
2873 * GNU/Linux support for fork, vfork, and exec.
2875 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2876 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2879 * GDB supports logging output to a file
2881 There are two new commands, "set logging" and "show logging", which can be
2882 used to capture GDB's output to a file.
2884 * The meaning of "detach" has changed for gdbserver
2886 The "detach" command will now resume the application, as documented. To
2887 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2890 * d10v, m68hc11 `regs' command deprecated
2892 The `info registers' command has been updated so that it displays the
2893 registers using a format identical to the old `regs' command.
2897 A new command, "maint set profile on/off", has been added. This command can
2898 be used to enable or disable profiling while running GDB, to profile a
2899 session or a set of commands. In addition there is a new configure switch,
2900 "--enable-profiling", which will cause GDB to be compiled with profiling
2901 data, for more informative profiling results.
2903 * Default MI syntax changed to "mi2".
2905 The default MI (machine interface) syntax, enabled by the command line
2906 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2907 "mi1", can be enabled by specifying the option "-i=mi1".
2909 Support for the original "mi0" syntax (included in GDB 5.0) has been
2912 Fix for gdb/192: removed extraneous space when displaying frame level.
2913 Fix for gdb/672: update changelist is now output in mi list format.
2914 Fix for gdb/702: a -var-assign that updates the value now shows up
2915 in a subsequent -var-update.
2917 * New native configurations.
2919 FreeBSD/amd64 x86_64-*-freebsd*
2921 * Multi-arched targets.
2923 HP/PA HPUX11 hppa*-*-hpux*
2924 Renesas M32R/D w/simulator m32r-*-elf*
2926 * OBSOLETE configurations and files
2928 Configurations that have been declared obsolete in this release have
2929 been commented out. Unless there is activity to revive these
2930 configurations, the next release of GDB will have their sources
2931 permanently REMOVED.
2933 Z8000 simulator z8k-zilog-none or z8ksim
2934 Matsushita MN10200 w/simulator mn10200-*-*
2935 H8/500 simulator h8500-hitachi-hms or h8500hms
2936 HP/PA running BSD hppa*-*-bsd*
2937 HP/PA running OSF/1 hppa*-*-osf*
2938 HP/PA Pro target hppa*-*-pro*
2939 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2940 Sequent family i[3456]86-sequent-sysv4*
2941 i[3456]86-sequent-sysv*
2942 i[3456]86-sequent-bsd*
2943 Tsqware Sparclet sparclet-*-*
2944 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2946 * REMOVED configurations and files
2949 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2950 IBM AIX PS/2 i[3456]86-*-aix
2951 i386 running Mach 3.0 i[3456]86-*-mach3*
2952 i386 running Mach i[3456]86-*-mach*
2953 i386 running OSF/1 i[3456]86-*osf1mk*
2954 HP/Apollo 68k Family m68*-apollo*-sysv*,
2956 m68*-hp-bsd*, m68*-hp-hpux*
2957 Argonaut Risc Chip (ARC) arc-*-*
2958 Mitsubishi D30V d30v-*-*
2959 Fujitsu FR30 fr30-*-elf*
2960 OS/9000 i[34]86-*-os9k
2961 I960 with MON960 i960-*-coff
2963 * MIPS $fp behavior changed
2965 The convenience variable $fp, for the MIPS, now consistently returns
2966 the address of the current frame's base. Previously, depending on the
2967 context, $fp could refer to either $sp or the current frame's base
2968 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2969 The GNU Source-Level Debugger''.
2971 *** Changes in GDB 5.3:
2973 * GNU/Linux shared library multi-threaded performance improved.
2975 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2976 `/proc', in preference to `ptrace' for memory reads. This may result
2977 in an improvement in the start-up time of multi-threaded, shared
2978 library applications when run under GDB. One GDB user writes: ``loads
2979 shared libs like mad''.
2981 * ``gdbserver'' now supports multi-threaded applications on some targets
2983 Support for debugging multi-threaded applications which use
2984 the GNU/Linux LinuxThreads package has been added for
2985 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2986 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2988 * GDB now supports C/C++ preprocessor macros.
2990 GDB now expands preprocessor macro invocations in C/C++ expressions,
2991 and provides various commands for showing macro definitions and how
2994 The new command `macro expand EXPRESSION' expands any macro
2995 invocations in expression, and shows the result.
2997 The new command `show macro MACRO-NAME' shows the definition of the
2998 macro named MACRO-NAME, and where it was defined.
3000 Most compilers don't include information about macros in the debugging
3001 information by default. In GCC 3.1, for example, you need to compile
3002 your program with the options `-gdwarf-2 -g3'. If the macro
3003 information is present in the executable, GDB will read it.
3005 * Multi-arched targets.
3007 DEC Alpha (partial) alpha*-*-*
3008 DEC VAX (partial) vax-*-*
3010 National Semiconductor NS32000 (partial) ns32k-*-*
3011 Motorola 68000 (partial) m68k-*-*
3012 Motorola MCORE mcore-*-*
3016 Fujitsu FRV architecture added by Red Hat frv*-*-*
3019 * New native configurations
3021 Alpha NetBSD alpha*-*-netbsd*
3022 SH NetBSD sh*-*-netbsdelf*
3023 MIPS NetBSD mips*-*-netbsd*
3024 UltraSPARC NetBSD sparc64-*-netbsd*
3026 * OBSOLETE configurations and files
3028 Configurations that have been declared obsolete in this release have
3029 been commented out. Unless there is activity to revive these
3030 configurations, the next release of GDB will have their sources
3031 permanently REMOVED.
3033 Mitsubishi D30V d30v-*-*
3034 OS/9000 i[34]86-*-os9k
3035 IBM AIX PS/2 i[3456]86-*-aix
3036 Fujitsu FR30 fr30-*-elf*
3037 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3038 Argonaut Risc Chip (ARC) arc-*-*
3039 i386 running Mach 3.0 i[3456]86-*-mach3*
3040 i386 running Mach i[3456]86-*-mach*
3041 i386 running OSF/1 i[3456]86-*osf1mk*
3042 HP/Apollo 68k Family m68*-apollo*-sysv*,
3044 m68*-hp-bsd*, m68*-hp-hpux*
3045 I960 with MON960 i960-*-coff
3047 * OBSOLETE languages
3049 CHILL, a Pascal like language used by telecommunications companies.
3051 * REMOVED configurations and files
3053 AMD 29k family via UDI a29k-amd-udi, udi29k
3054 A29K VxWorks a29k-*-vxworks
3055 AMD 29000 embedded, using EBMON a29k-none-none
3056 AMD 29000 embedded with COFF a29k-none-coff
3057 AMD 29000 embedded with a.out a29k-none-aout
3059 testsuite/gdb.hp/gdb.threads-hp/ directory
3061 * New command "set max-user-call-depth <nnn>"
3063 This command allows the user to limit the call depth of user-defined
3064 commands. The default is 1024.
3066 * Changes in FreeBSD/i386 native debugging.
3068 Support for the "generate-core-file" has been added.
3070 * New commands "dump", "append", and "restore".
3072 These commands allow data to be copied from target memory
3073 to a bfd-format or binary file (dump and append), and back
3074 from a file into memory (restore).
3076 * Improved "next/step" support on multi-processor Alpha Tru64.
3078 The previous single-step mechanism could cause unpredictable problems,
3079 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3080 of a software single-step mechanism prevents this.
3082 *** Changes in GDB 5.2.1:
3090 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3091 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3092 Fix, by Joel Brobecker imported from mainline.
3094 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3095 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3096 Fix, by Fred Fish, imported from mainline.
3098 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3099 Surprisingly enough, it works now.
3100 By Michal Ludvig, imported from mainline.
3102 i386 hardware watchpoint support:
3103 avoid misses on second run for some targets.
3104 By Pierre Muller, imported from mainline.
3106 *** Changes in GDB 5.2:
3108 * New command "set trust-readonly-sections on[off]".
3110 This command is a hint that tells gdb that read-only sections
3111 really are read-only (ie. that their contents will not change).
3112 In this mode, gdb will go to the object file rather than the
3113 target to read memory from read-only sections (such as ".text").
3114 This can be a significant performance improvement on some
3115 (notably embedded) targets.
3117 * New command "generate-core-file" (or "gcore").
3119 This new gdb command allows the user to drop a core file of the child
3120 process state at any time. So far it's been implemented only for
3121 GNU/Linux and Solaris, but should be relatively easily ported to other
3122 hosts. Argument is core file name (defaults to core.<pid>).
3124 * New command line option
3126 GDB now accepts --pid or -p followed by a process id.
3128 * Change in command line behavior -- corefiles vs. process ids.
3130 There is a subtle behavior in the way in which GDB handles
3131 command line arguments. The first non-flag argument is always
3132 a program to debug, but the second non-flag argument may either
3133 be a corefile or a process id. Previously, GDB would attempt to
3134 open the second argument as a corefile, and if that failed, would
3135 issue a superfluous error message and then attempt to attach it as
3136 a process. Now, if the second argument begins with a non-digit,
3137 it will be treated as a corefile. If it begins with a digit,
3138 GDB will attempt to attach it as a process, and if no such process
3139 is found, will then attempt to open it as a corefile.
3141 * Changes in ARM configurations.
3143 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3144 configuration is fully multi-arch.
3146 * New native configurations
3148 ARM NetBSD arm*-*-netbsd*
3149 x86 OpenBSD i[3456]86-*-openbsd*
3150 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3151 Sparc64 running FreeBSD sparc64-*-freebsd*
3155 Sanyo XStormy16 xstormy16-elf
3157 * OBSOLETE configurations and files
3159 Configurations that have been declared obsolete in this release have
3160 been commented out. Unless there is activity to revive these
3161 configurations, the next release of GDB will have their sources
3162 permanently REMOVED.
3164 AMD 29k family via UDI a29k-amd-udi, udi29k
3165 A29K VxWorks a29k-*-vxworks
3166 AMD 29000 embedded, using EBMON a29k-none-none
3167 AMD 29000 embedded with COFF a29k-none-coff
3168 AMD 29000 embedded with a.out a29k-none-aout
3170 testsuite/gdb.hp/gdb.threads-hp/ directory
3172 * REMOVED configurations and files
3174 TI TMS320C80 tic80-*-*
3176 PowerPC Solaris powerpcle-*-solaris*
3177 PowerPC Windows NT powerpcle-*-cygwin32
3178 PowerPC Netware powerpc-*-netware*
3179 Harris/CXUX m88k m88*-harris-cxux*
3180 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3181 ns32k-utek-sysv* ns32k-utek-*
3182 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3183 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3184 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3185 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3186 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3188 * Changes to command line processing
3190 The new `--args' feature can be used to specify command-line arguments
3191 for the inferior from gdb's command line.
3193 * Changes to key bindings
3195 There is a new `operate-and-get-next' function bound to `C-o'.
3197 *** Changes in GDB 5.1.1
3199 Fix compile problem on DJGPP.
3201 Fix a problem with floating-point registers on the i386 being
3204 Fix to stop GDB crashing on .debug_str debug info.
3206 Numerous documentation fixes.
3208 Numerous testsuite fixes.
3210 *** Changes in GDB 5.1:
3212 * New native configurations
3214 Alpha FreeBSD alpha*-*-freebsd*
3215 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3216 MIPS GNU/Linux mips*-*-linux*
3217 MIPS SGI Irix 6.x mips*-sgi-irix6*
3218 ia64 AIX ia64-*-aix*
3219 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3223 Motorola 68HC11 and 68HC12 m68hc11-elf
3225 UltraSparc running GNU/Linux sparc64-*-linux*
3227 * OBSOLETE configurations and files
3229 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3230 Harris/CXUX m88k m88*-harris-cxux*
3231 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3232 ns32k-utek-sysv* ns32k-utek-*
3233 TI TMS320C80 tic80-*-*
3235 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3236 PowerPC Solaris powerpcle-*-solaris*
3237 PowerPC Windows NT powerpcle-*-cygwin32
3238 PowerPC Netware powerpc-*-netware*
3239 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3240 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3241 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3242 Apple Macintosh (MPW) host N/A
3244 stuff.c (Program to stuff files into a specially prepared space in kdb)
3245 kdb-start.c (Main loop for the standalone kernel debugger)
3247 Configurations that have been declared obsolete in this release have
3248 been commented out. Unless there is activity to revive these
3249 configurations, the next release of GDB will have their sources
3250 permanently REMOVED.
3252 * REMOVED configurations and files
3254 Altos 3068 m68*-altos-*
3255 Convex c1-*-*, c2-*-*
3257 ARM RISCix arm-*-* (as host)
3261 * GDB has been converted to ISO C.
3263 GDB's source code has been converted to ISO C. In particular, the
3264 sources are fully protoized, and rely on standard headers being
3269 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3271 * The MI enabled by default.
3273 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3274 revised and enabled by default. Packages which use GDB as a debugging
3275 engine behind a UI or another front end are encouraged to switch to
3276 using the GDB/MI interface, instead of the old annotations interface
3277 which is now deprecated.
3279 * Support for debugging Pascal programs.
3281 GDB now includes support for debugging Pascal programs. The following
3282 main features are supported:
3284 - Pascal-specific data types such as sets;
3286 - automatic recognition of Pascal sources based on file-name
3289 - Pascal-style display of data types, variables, and functions;
3291 - a Pascal expression parser.
3293 However, some important features are not yet supported.
3295 - Pascal string operations are not supported at all;
3297 - there are some problems with boolean types;
3299 - Pascal type hexadecimal constants are not supported
3300 because they conflict with the internal variables format;
3302 - support for Pascal objects and classes is not full yet;
3304 - unlike Pascal, GDB is case-sensitive for symbol names.
3306 * Changes in completion.
3308 Commands such as `shell', `run' and `set args', which pass arguments
3309 to inferior programs, now complete on file names, similar to what
3310 users expect at the shell prompt.
3312 Commands which accept locations, such as `disassemble', `print',
3313 `breakpoint', `until', etc. now complete on filenames as well as
3314 program symbols. Thus, if you type "break foob TAB", and the source
3315 files linked into the programs include `foobar.c', that file name will
3316 be one of the candidates for completion. However, file names are not
3317 considered for completion after you typed a colon that delimits a file
3318 name from a name of a function in that file, as in "break foo.c:bar".
3320 `set demangle-style' completes on available demangling styles.
3322 * New platform-independent commands:
3324 It is now possible to define a post-hook for a command as well as a
3325 hook that runs before the command. For more details, see the
3326 documentation of `hookpost' in the GDB manual.
3328 * Changes in GNU/Linux native debugging.
3330 Support for debugging multi-threaded programs has been completely
3331 revised for all platforms except m68k and sparc. You can now debug as
3332 many threads as your system allows you to have.
3334 Attach/detach is supported for multi-threaded programs.
3336 Support for SSE registers was added for x86. This doesn't work for
3337 multi-threaded programs though.
3339 * Changes in MIPS configurations.
3341 Multi-arch support is enabled for all MIPS configurations.
3343 GDB can now be built as native debugger on SGI Irix 6.x systems for
3344 debugging n32 executables. (Debugging 64-bit executables is not yet
3347 * Unified support for hardware watchpoints in all x86 configurations.
3349 Most (if not all) native x86 configurations support hardware-assisted
3350 breakpoints and watchpoints in a unified manner. This support
3351 implements debug register sharing between watchpoints, which allows to
3352 put a virtually infinite number of watchpoints on the same address,
3353 and also supports watching regions up to 16 bytes with several debug
3356 The new maintenance command `maintenance show-debug-regs' toggles
3357 debugging print-outs in functions that insert, remove, and test
3358 watchpoints and hardware breakpoints.
3360 * Changes in the DJGPP native configuration.
3362 New command ``info dos sysinfo'' displays assorted information about
3363 the CPU, OS, memory, and DPMI server.
3365 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3366 display information about segment descriptors stored in GDT, LDT, and
3369 New commands ``info dos pde'' and ``info dos pte'' display entries
3370 from Page Directory and Page Tables (for now works with CWSDPMI only).
3371 New command ``info dos address-pte'' displays the Page Table entry for
3372 a given linear address.
3374 GDB can now pass command lines longer than 126 characters to the
3375 program being debugged (requires an update to the libdbg.a library
3376 which is part of the DJGPP development kit).
3378 DWARF2 debug info is now supported.
3380 It is now possible to `step' and `next' through calls to `longjmp'.
3382 * Changes in documentation.
3384 All GDB documentation was converted to GFDL, the GNU Free
3385 Documentation License.
3387 Tracepoints-related commands are now fully documented in the GDB
3390 TUI, the Text-mode User Interface, is now documented in the manual.
3392 Tracepoints-related commands are now fully documented in the GDB
3395 The "GDB Internals" manual now has an index. It also includes
3396 documentation of `ui_out' functions, GDB coding standards, x86
3397 hardware watchpoints, and memory region attributes.
3399 * GDB's version number moved to ``version.in''
3401 The Makefile variable VERSION has been replaced by the file
3402 ``version.in''. People creating GDB distributions should update the
3403 contents of this file.
3407 GUD support is now a standard part of the EMACS distribution.
3409 *** Changes in GDB 5.0:
3411 * Improved support for debugging FP programs on x86 targets
3413 Unified and much-improved support for debugging floating-point
3414 programs on all x86 targets. In particular, ``info float'' now
3415 displays the FP registers in the same format on all x86 targets, with
3416 greater level of detail.
3418 * Improvements and bugfixes in hardware-assisted watchpoints
3420 It is now possible to watch array elements, struct members, and
3421 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3422 on x86 targets no longer erroneously trigger when the address is
3425 * Improvements in the native DJGPP version of GDB
3427 The distribution now includes all the scripts and auxiliary files
3428 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3429 machines ``out of the box''.
3431 The DJGPP version can now debug programs that use signals. It is
3432 possible to catch signals that happened in the debuggee, deliver
3433 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3434 would kill the program being debugged.) Programs that hook hardware
3435 interrupts (keyboard, timer, etc.) can also be debugged.
3437 It is now possible to debug DJGPP programs that redirect their
3438 standard handles or switch them to raw (as opposed to cooked) mode, or
3439 even close them. The command ``run < foo > bar'' works as expected,
3440 and ``info terminal'' reports useful information about the debuggee's
3441 terminal, including raw/cooked mode, redirection, etc.
3443 The DJGPP version now uses termios functions for console I/O, which
3444 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3447 DOS-style file names with drive letters are now fully supported by
3450 It is now possible to debug DJGPP programs that switch their working
3451 directory. It is also possible to rerun the debuggee any number of
3452 times without restarting GDB; thus, you can use the same setup,
3453 breakpoints, etc. for many debugging sessions.
3455 * New native configurations
3457 ARM GNU/Linux arm*-*-linux*
3458 PowerPC GNU/Linux powerpc-*-linux*
3462 Motorola MCore mcore-*-*
3463 x86 VxWorks i[3456]86-*-vxworks*
3464 PowerPC VxWorks powerpc-*-vxworks*
3465 TI TMS320C80 tic80-*-*
3467 * OBSOLETE configurations
3469 Altos 3068 m68*-altos-*
3470 Convex c1-*-*, c2-*-*
3472 ARM RISCix arm-*-* (as host)
3475 Configurations that have been declared obsolete will be commented out,
3476 but the code will be left in place. If there is no activity to revive
3477 these configurations before the next release of GDB, the sources will
3478 be permanently REMOVED.
3480 * Gould support removed
3482 Support for the Gould PowerNode and NP1 has been removed.
3484 * New features for SVR4
3486 On SVR4 native platforms (such as Solaris), if you attach to a process
3487 without first loading a symbol file, GDB will now attempt to locate and
3488 load symbols from the running process's executable file.
3490 * Many C++ enhancements
3492 C++ support has been greatly improved. Overload resolution now works properly
3493 in almost all cases. RTTI support is on the way.
3495 * Remote targets can connect to a sub-program
3497 A popen(3) style serial-device has been added. This device starts a
3498 sub-process (such as a stand-alone simulator) and then communicates
3499 with that. The sub-program to run is specified using the syntax
3500 ``|<program> <args>'' vis:
3502 (gdb) set remotedebug 1
3503 (gdb) target extended-remote |mn10300-elf-sim program-args
3505 * MIPS 64 remote protocol
3507 A long standing bug in the mips64 remote protocol where by GDB
3508 expected certain 32 bit registers (ex SR) to be transfered as 32
3509 instead of 64 bits has been fixed.
3511 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3512 added to provide backward compatibility with older versions of GDB.
3514 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3516 The command ``set remotebinarydownload'' command has been replaced by
3517 ``set remote X-packet''. Other commands in ``set remote'' family
3518 include ``set remote P-packet''.
3520 * Breakpoint commands accept ranges.
3522 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3523 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3524 ``tracepoint passcount'' also accepts a range of tracepoints.
3526 * ``apropos'' command added.
3528 The ``apropos'' command searches through command names and
3529 documentation strings, printing out matches, making it much easier to
3530 try to find a command that does what you are looking for.
3534 A new machine oriented interface (MI) has been added to GDB. This
3535 interface is designed for debug environments running GDB as a separate
3536 process. This is part of the long term libGDB project. See the
3537 "GDB/MI" chapter of the GDB manual for further information. It can be
3538 enabled by configuring with:
3540 .../configure --enable-gdbmi
3542 *** Changes in GDB-4.18:
3544 * New native configurations
3546 HP-UX 10.20 hppa*-*-hpux10.20
3547 HP-UX 11.x hppa*-*-hpux11.0*
3548 M68K GNU/Linux m68*-*-linux*
3552 Fujitsu FR30 fr30-*-elf*
3553 Intel StrongARM strongarm-*-*
3554 Mitsubishi D30V d30v-*-*
3556 * OBSOLETE configurations
3558 Gould PowerNode, NP1 np1-*-*, pn-*-*
3560 Configurations that have been declared obsolete will be commented out,
3561 but the code will be left in place. If there is no activity to revive
3562 these configurations before the next release of GDB, the sources will
3563 be permanently REMOVED.
3567 As a compatibility experiment, GDB's source files buildsym.h and
3568 buildsym.c have been converted to pure standard C, no longer
3569 containing any K&R compatibility code. We believe that all systems in
3570 use today either come with a standard C compiler, or have a GCC port
3571 available. If this is not true, please report the affected
3572 configuration to bug-gdb@gnu.org immediately. See the README file for
3573 information about getting a standard C compiler if you don't have one
3578 GDB now uses readline 2.2.
3580 * set extension-language
3582 You can now control the mapping between filename extensions and source
3583 languages by using the `set extension-language' command. For instance,
3584 you can ask GDB to treat .c files as C++ by saying
3585 set extension-language .c c++
3586 The command `info extensions' lists all of the recognized extensions
3587 and their associated languages.
3589 * Setting processor type for PowerPC and RS/6000
3591 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3592 you can use the `set processor' command to specify what variant of the
3593 PowerPC family you are debugging. The command
3597 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3598 following PowerPC and RS6000 variants:
3600 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3601 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3603 403GC IBM PowerPC 403GC
3604 505 Motorola PowerPC 505
3605 860 Motorola PowerPC 860 or 850
3606 601 Motorola PowerPC 601
3607 602 Motorola PowerPC 602
3608 603 Motorola/IBM PowerPC 603 or 603e
3609 604 Motorola PowerPC 604 or 604e
3610 750 Motorola/IBM PowerPC 750 or 750
3612 At the moment, this command just tells GDB what to name the
3613 special-purpose processor registers. Since almost all the affected
3614 registers are inaccessible to user-level programs, this command is
3615 only useful for remote debugging in its present form.
3619 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3620 more extensive support for HP-UX. Added features include shared
3621 library support, kernel threads and hardware watchpoints for 11.00,
3622 support for HP's ANSI C and C++ compilers, and a compatibility mode
3623 for xdb and dbx commands.
3627 HP's donation includes the new concept of catchpoints, which is a
3628 generalization of the old catch command. On HP-UX, it is now possible
3629 to catch exec, fork, and vfork, as well as library loading.
3631 This means that the existing catch command has changed; its first
3632 argument now specifies the type of catch to be set up. See the
3633 output of "help catch" for a list of catchpoint types.
3635 * Debugging across forks
3637 On HP-UX, you can choose which process to debug when a fork() happens
3642 HP has donated a curses-based terminal user interface (TUI). To get
3643 it, build with --enable-tui. Although this can be enabled for any
3644 configuration, at present it only works for native HP debugging.
3646 * GDB remote protocol additions
3648 A new protocol packet 'X' that writes binary data is now available.
3649 Default behavior is to try 'X', then drop back to 'M' if the stub
3650 fails to respond. The settable variable `remotebinarydownload'
3651 allows explicit control over the use of 'X'.
3653 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3654 full 64-bit address. The command
3656 set remoteaddresssize 32
3658 can be used to revert to the old behaviour. For existing remote stubs
3659 the change should not be noticed, as the additional address information
3662 In order to assist in debugging stubs, you may use the maintenance
3663 command `packet' to send any text string to the stub. For instance,
3665 maint packet heythere
3667 sends the packet "$heythere#<checksum>". Note that it is very easy to
3668 disrupt a debugging session by sending the wrong packet at the wrong
3671 The compare-sections command allows you to compare section data on the
3672 target to what is in the executable file without uploading or
3673 downloading, by comparing CRC checksums.
3675 * Tracing can collect general expressions
3677 You may now collect general expressions at tracepoints. This requires
3678 further additions to the target-side stub; see tracepoint.c and
3679 doc/agentexpr.texi for further details.
3681 * mask-address variable for Mips
3683 For Mips targets, you may control the zeroing of the upper 32 bits of
3684 a 64-bit address by entering `set mask-address on'. This is mainly
3685 of interest to users of embedded R4xxx and R5xxx processors.
3687 * Higher serial baud rates
3689 GDB's serial code now allows you to specify baud rates 57600, 115200,
3690 230400, and 460800 baud. (Note that your host system may not be able
3691 to achieve all of these rates.)
3695 The i960 configuration now includes an initial implementation of a
3696 builtin simulator, contributed by Jim Wilson.
3699 *** Changes in GDB-4.17:
3701 * New native configurations
3703 Alpha GNU/Linux alpha*-*-linux*
3704 Unixware 2.x i[3456]86-unixware2*
3705 Irix 6.x mips*-sgi-irix6*
3706 PowerPC GNU/Linux powerpc-*-linux*
3707 PowerPC Solaris powerpcle-*-solaris*
3708 Sparc GNU/Linux sparc-*-linux*
3709 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3713 Argonaut Risc Chip (ARC) arc-*-*
3714 Hitachi H8/300S h8300*-*-*
3715 Matsushita MN10200 w/simulator mn10200-*-*
3716 Matsushita MN10300 w/simulator mn10300-*-*
3717 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3718 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3719 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3720 Mitsubishi D10V w/simulator d10v-*-*
3721 Mitsubishi M32R/D w/simulator m32r-*-elf*
3722 Tsqware Sparclet sparclet-*-*
3723 NEC V850 w/simulator v850-*-*
3725 * New debugging protocols
3727 ARM with RDI protocol arm*-*-*
3728 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3729 DDB and LSI variants of PMON protocol mips*-*-*
3730 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3731 PowerPC with SDS protocol powerpc{,le}-*-eabi
3732 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3736 All configurations can now understand and use the DWARF 2 debugging
3737 format. The choice is automatic, if the symbol file contains DWARF 2
3742 GDB now includes basic Java language support. This support is
3743 only useful with Java compilers that produce native machine code.
3745 * solib-absolute-prefix and solib-search-path
3747 For SunOS and SVR4 shared libraries, you may now set the prefix for
3748 loading absolute shared library symbol files, and the search path for
3749 locating non-absolute shared library symbol files.
3751 * Live range splitting
3753 GDB can now effectively debug code for which GCC has performed live
3754 range splitting as part of its optimization. See gdb/doc/LRS for
3755 more details on the expected format of the stabs information.
3759 GDB's support for the GNU Hurd, including thread debugging, has been
3760 updated to work with current versions of the Hurd.
3764 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3765 instruction set. ARM GDB automatically detects when Thumb
3766 instructions are in use, and adjusts disassembly and backtracing
3771 GDB's MIPS target configurations now handle the MIP16 16-bit
3776 GDB now includes support for overlays; if an executable has been
3777 linked such that multiple sections are based at the same address, GDB
3778 will decide which section to use for symbolic info. You can choose to
3779 control the decision manually, using overlay commands, or implement
3780 additional target-side support and use "overlay load-target" to bring
3781 in the overlay mapping. Do "help overlay" for more detail.
3785 The command "info symbol <address>" displays information about
3786 the symbol at the specified address.
3790 The standard remote protocol now includes an extension that allows
3791 asynchronous collection and display of trace data. This requires
3792 extensive support in the target-side debugging stub. Tracing mode
3793 includes a new interaction mode in GDB and new commands: see the
3794 file tracepoint.c for more details.
3798 Configurations for embedded MIPS now include a simulator contributed
3799 by Cygnus Solutions. The simulator supports the instruction sets
3800 of most MIPS variants.
3804 Sparc configurations may now include the ERC32 simulator contributed
3805 by the European Space Agency. The simulator is not built into
3806 Sparc targets by default; configure with --enable-sim to include it.
3810 For target configurations that may include multiple variants of a
3811 basic architecture (such as MIPS and SH), you may now set the
3812 architecture explicitly. "set arch" sets, "info arch" lists
3813 the possible architectures.
3815 *** Changes in GDB-4.16:
3817 * New native configurations
3819 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3820 M68K NetBSD m68k-*-netbsd*
3821 PowerPC AIX 4.x powerpc-*-aix*
3822 PowerPC MacOS powerpc-*-macos*
3823 PowerPC Windows NT powerpcle-*-cygwin32
3824 RS/6000 AIX 4.x rs6000-*-aix4*
3828 ARM with RDP protocol arm-*-*
3829 I960 with MON960 i960-*-coff
3830 MIPS VxWorks mips*-*-vxworks*
3831 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3832 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3834 Matra Sparclet sparclet-*-*
3838 The powerpc-eabi configuration now includes the PSIM simulator,
3839 contributed by Andrew Cagney, with assistance from Mike Meissner.
3840 PSIM is a very elaborate model of the PowerPC, including not only
3841 basic instruction set execution, but also details of execution unit
3842 performance and I/O hardware. See sim/ppc/README for more details.
3846 GDB now works with Solaris 2.5.
3848 * Windows 95/NT native
3850 GDB will now work as a native debugger on Windows 95 and Windows NT.
3851 To build it from source, you must use the "gnu-win32" environment,
3852 which uses a DLL to emulate enough of Unix to run the GNU tools.
3853 Further information, binaries, and sources are available at
3854 ftp.cygnus.com, under pub/gnu-win32.
3856 * dont-repeat command
3858 If a user-defined command includes the command `dont-repeat', then the
3859 command will not be repeated if the user just types return. This is
3860 useful if the command is time-consuming to run, so that accidental
3861 extra keystrokes don't run the same command many times.
3863 * Send break instead of ^C
3865 The standard remote protocol now includes an option to send a break
3866 rather than a ^C to the target in order to interrupt it. By default,
3867 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3869 * Remote protocol timeout
3871 The standard remote protocol includes a new variable `remotetimeout'
3872 that allows you to set the number of seconds before GDB gives up trying
3873 to read from the target. The default value is 2.
3875 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3877 By default GDB will automatically keep track of objects as they are
3878 loaded and unloaded by the dynamic linker. By using the command `set
3879 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3880 when shared library events occur, thus allowing you to set breakpoints
3881 in shared libraries which are explicitly loaded by the inferior.
3883 Note this feature does not work on hpux8. On hpux9 you must link
3884 /usr/lib/end.o into your program. This feature should work
3885 automatically on hpux10.
3887 * Irix 5.x hardware watchpoint support
3889 Irix 5 configurations now support the use of hardware watchpoints.
3891 * Mips protocol "SYN garbage limit"
3893 When debugging a Mips target using the `target mips' protocol, you
3894 may set the number of characters that GDB will ignore by setting
3895 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3896 every character. The default value is 1050.
3898 * Recording and replaying remote debug sessions
3900 If you set `remotelogfile' to the name of a file, gdb will write to it
3901 a recording of a remote debug session. This recording may then be
3902 replayed back to gdb using "gdbreplay". See gdbserver/README for
3903 details. This is useful when you have a problem with GDB while doing
3904 remote debugging; you can make a recording of the session and send it
3905 to someone else, who can then recreate the problem.
3907 * Speedups for remote debugging
3909 GDB includes speedups for downloading and stepping MIPS systems using
3910 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3911 and more efficient S-record downloading.
3913 * Memory use reductions and statistics collection
3915 GDB now uses less memory and reports statistics about memory usage.
3916 Try the `maint print statistics' command, for example.
3918 *** Changes in GDB-4.15:
3920 * Psymtabs for XCOFF
3922 The symbol reader for AIX GDB now uses partial symbol tables. This
3923 can greatly improve startup time, especially for large executables.
3925 * Remote targets use caching
3927 Remote targets now use a data cache to speed up communication with the
3928 remote side. The data cache could lead to incorrect results because
3929 it doesn't know about volatile variables, thus making it impossible to
3930 debug targets which use memory mapped I/O devices. `set remotecache
3931 off' turns the the data cache off.
3933 * Remote targets may have threads
3935 The standard remote protocol now includes support for multiple threads
3936 in the target system, using new protocol commands 'H' and 'T'. See
3937 gdb/remote.c for details.
3941 If GDB is configured with `--enable-netrom', then it will include
3942 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3943 acts as though it is a bank of ROM on the target board, but you can
3944 write into it over the network. GDB's support consists only of
3945 support for fast loading into the emulated ROM; to debug, you must use
3946 another protocol, such as standard remote protocol. The usual
3947 sequence is something like
3949 target nrom <netrom-hostname>
3951 target remote <netrom-hostname>:1235
3955 GDB now includes support for the Apple Macintosh, as a host only. It
3956 may be run as either an MPW tool or as a standalone application, and
3957 it can debug through the serial port. All the usual GDB commands are
3958 available, but to the target command, you must supply "serial" as the
3959 device type instead of "/dev/ttyXX". See mpw-README in the main
3960 directory for more information on how to build. The MPW configuration
3961 scripts */mpw-config.in support only a few targets, and only the
3962 mips-idt-ecoff target has been tested.
3966 GDB configuration now uses autoconf. This is not user-visible,
3967 but does simplify configuration and building.
3971 GDB now supports hpux10.
3973 *** Changes in GDB-4.14:
3975 * New native configurations
3977 x86 FreeBSD i[345]86-*-freebsd
3978 x86 NetBSD i[345]86-*-netbsd
3979 NS32k NetBSD ns32k-*-netbsd
3980 Sparc NetBSD sparc-*-netbsd
3984 A29K VxWorks a29k-*-vxworks
3985 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3986 CPU32 EST-300 emulator m68*-*-est*
3987 PowerPC ELF powerpc-*-elf
3990 * Alpha OSF/1 support for procfs
3992 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3993 possible to attach to running processes. As the mounting of the /proc
3994 filesystem is optional on the Alpha, GDB automatically determines
3995 the availability of /proc during startup. This can lead to problems
3996 if /proc is unmounted after GDB has been started.
3998 * Arguments to user-defined commands
4000 User commands may accept up to 10 arguments separated by whitespace.
4001 Arguments are accessed within the user command via $arg0..$arg9. A
4004 print $arg0 + $arg1 + $arg2
4006 To execute the command use:
4009 Defines the command "adder" which prints the sum of its three arguments.
4010 Note the arguments are text substitutions, so they may reference variables,
4011 use complex expressions, or even perform inferior function calls.
4013 * New `if' and `while' commands
4015 This makes it possible to write more sophisticated user-defined
4016 commands. Both commands take a single argument, which is the
4017 expression to evaluate, and must be followed by the commands to
4018 execute, one per line, if the expression is nonzero, the list being
4019 terminated by the word `end'. The `if' command list may include an
4020 `else' word, which causes the following commands to be executed only
4021 if the expression is zero.
4023 * Fortran source language mode
4025 GDB now includes partial support for Fortran 77. It will recognize
4026 Fortran programs and can evaluate a subset of Fortran expressions, but
4027 variables and functions may not be handled correctly. GDB will work
4028 with G77, but does not yet know much about symbols emitted by other
4031 * Better HPUX support
4033 Most debugging facilities now work on dynamic executables for HPPAs
4034 running hpux9 or later. You can attach to running dynamically linked
4035 processes, but by default the dynamic libraries will be read-only, so
4036 for instance you won't be able to put breakpoints in them. To change
4037 that behavior do the following before running the program:
4043 This will cause the libraries to be mapped private and read-write.
4044 To revert to the normal behavior, do this:
4050 You cannot set breakpoints or examine data in the library until after
4051 the library is loaded if the function/data symbols do not have
4054 GDB can now also read debug symbols produced by the HP C compiler on
4055 HPPAs (sorry, no C++, Fortran or 68k support).
4057 * Target byte order now dynamically selectable
4059 You can choose which byte order to use with a target system, via the
4060 commands "set endian big" and "set endian little", and you can see the
4061 current setting by using "show endian". You can also give the command
4062 "set endian auto", in which case GDB will use the byte order
4063 associated with the executable. Currently, only embedded MIPS
4064 configurations support dynamic selection of target byte order.
4066 * New DOS host serial code
4068 This version uses DPMI interrupts to handle buffered I/O, so you
4069 no longer need to run asynctsr when debugging boards connected to
4072 *** Changes in GDB-4.13:
4074 * New "complete" command
4076 This lists all the possible completions for the rest of the line, if it
4077 were to be given as a command itself. This is intended for use by emacs.
4079 * Trailing space optional in prompt
4081 "set prompt" no longer adds a space for you after the prompt you set. This
4082 allows you to set a prompt which ends in a space or one that does not.
4084 * Breakpoint hit counts
4086 "info break" now displays a count of the number of times the breakpoint
4087 has been hit. This is especially useful in conjunction with "ignore"; you
4088 can ignore a large number of breakpoint hits, look at the breakpoint info
4089 to see how many times the breakpoint was hit, then run again, ignoring one
4090 less than that number, and this will get you quickly to the last hit of
4093 * Ability to stop printing at NULL character
4095 "set print null-stop" will cause GDB to stop printing the characters of
4096 an array when the first NULL is encountered. This is useful when large
4097 arrays actually contain only short strings.
4099 * Shared library breakpoints
4101 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4102 breakpoints in shared libraries before the executable is run.
4104 * Hardware watchpoints
4106 There is a new hardware breakpoint for the watch command for sparclite
4107 targets. See gdb/sparclite/hw_breakpoint.note.
4109 Hardware watchpoints are also now supported under GNU/Linux.
4113 Annotations have been added. These are for use with graphical interfaces,
4114 and are still experimental. Currently only gdba.el uses these.
4116 * Improved Irix 5 support
4118 GDB now works properly with Irix 5.2.
4120 * Improved HPPA support
4122 GDB now works properly with the latest GCC and GAS.
4124 * New native configurations
4126 Sequent PTX4 i[34]86-sequent-ptx4
4127 HPPA running OSF/1 hppa*-*-osf*
4128 Atari TT running SVR4 m68*-*-sysv4*
4129 RS/6000 LynxOS rs6000-*-lynxos*
4133 OS/9000 i[34]86-*-os9k
4134 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4137 * Hitachi SH7000 and E7000-PC ICE support
4139 There is now support for communicating with the Hitachi E7000-PC ICE.
4140 This is available automatically when GDB is configured for the SH.
4144 As usual, a variety of small fixes and improvements, both generic
4145 and configuration-specific. See the ChangeLog for more detail.
4147 *** Changes in GDB-4.12:
4149 * Irix 5 is now supported
4153 GDB-4.12 on the HPPA has a number of changes which make it unable
4154 to debug the output from the currently released versions of GCC and
4155 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4156 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4157 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4160 *** Changes in GDB-4.11:
4162 * User visible changes:
4166 The "set remotedebug" option is now consistent between the mips remote
4167 target, remote targets using the gdb-specific protocol, UDI (AMD's
4168 debug protocol for the 29k) and the 88k bug monitor. It is now an
4169 integer specifying a debug level (normally 0 or 1, but 2 means more
4170 debugging info for the mips target).
4172 * DEC Alpha native support
4174 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4175 debug info, but GDB works fairly well with the DEC compiler and should
4176 work with a future GCC release. See the README file for a few
4177 Alpha-specific notes.
4179 * Preliminary thread implementation
4181 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4183 * LynxOS native and target support for 386
4185 This release has been hosted on LynxOS 2.2, and also can be configured
4186 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4189 * Improvements in C++ mangling/demangling.
4191 This release has much better g++ debugging, specifically in name
4192 mangling/demangling, virtual function calls, print virtual table,
4193 call methods, ...etc.
4195 *** Changes in GDB-4.10:
4197 * User visible changes:
4199 Remote debugging using the GDB-specific (`target remote') protocol now
4200 supports the `load' command. This is only useful if you have some
4201 other way of getting the stub to the target system, and you can put it
4202 somewhere in memory where it won't get clobbered by the download.
4204 Filename completion now works.
4206 When run under emacs mode, the "info line" command now causes the
4207 arrow to point to the line specified. Also, "info line" prints
4208 addresses in symbolic form (as well as hex).
4210 All vxworks based targets now support a user settable option, called
4211 vxworks-timeout. This option represents the number of seconds gdb
4212 should wait for responses to rpc's. You might want to use this if
4213 your vxworks target is, perhaps, a slow software simulator or happens
4214 to be on the far side of a thin network line.
4218 This release contains support for using a DEC alpha as a GDB host for
4219 cross debugging. Native alpha debugging is not supported yet.
4222 *** Changes in GDB-4.9:
4226 This is the first GDB release which is accompanied by a matching testsuite.
4227 The testsuite requires installation of dejagnu, which should be available
4228 via ftp from most sites that carry GNU software.
4232 'Cfront' style demangling has had its name changed to 'ARM' style, to
4233 emphasize that it was written from the specifications in the C++ Annotated
4234 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4235 disclaimers, it still generated too much confusion with users attempting to
4236 use gdb with AT&T cfront.
4240 GDB now uses a standard remote interface to a simulator library.
4241 So far, the library contains simulators for the Zilog Z8001/2, the
4242 Hitachi H8/300, H8/500 and Super-H.
4244 * New targets supported
4246 H8/300 simulator h8300-hitachi-hms or h8300hms
4247 H8/500 simulator h8500-hitachi-hms or h8500hms
4248 SH simulator sh-hitachi-hms or sh
4249 Z8000 simulator z8k-zilog-none or z8ksim
4250 IDT MIPS board over serial line mips-idt-ecoff
4252 Cross-debugging to GO32 targets is supported. It requires a custom
4253 version of the i386-stub.c module which is integrated with the
4254 GO32 memory extender.
4256 * New remote protocols
4258 MIPS remote debugging protocol.
4260 * New source languages supported
4262 This version includes preliminary support for Chill, a Pascal like language
4263 used by telecommunications companies. Chill support is also being integrated
4264 into the GNU compiler, but we don't know when it will be publically available.
4267 *** Changes in GDB-4.8:
4269 * HP Precision Architecture supported
4271 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4272 version of this support was available as a set of patches from the
4273 University of Utah. GDB does not support debugging of programs
4274 compiled with the HP compiler, because HP will not document their file
4275 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4276 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4278 Many problems in the preliminary version have been fixed.
4280 * Faster and better demangling
4282 We have improved template demangling and fixed numerous bugs in the GNU style
4283 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4284 character types (wchar_t) are now supported. Demangling of each symbol is now
4285 only done once, and is cached when the symbol table for a file is read in.
4286 This results in a small increase in memory usage for C programs, a moderate
4287 increase in memory usage for C++ programs, and a fantastic speedup in
4290 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4291 from the specifications in the Annotated Reference Manual, which AT&T's
4292 compiler does not actually implement.
4294 * G++ multiple inheritance compiler problem
4296 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4297 inheritance lattices was reworked to properly discover ambiguities. We
4298 recently found an example which causes this new algorithm to fail in a
4299 very subtle way, producing bad debug information for those classes.
4300 The file 'gcc.patch' (in this directory) can be applied to gcc to
4301 circumvent the problem. A future GCC release will contain a complete
4304 The previous G++ debug info problem (mentioned below for the gdb-4.7
4305 release) is fixed in gcc version 2.3.2.
4307 * Improved configure script
4309 The `configure' script will now attempt to guess your system type if
4310 you don't supply a host system type. The old scheme of supplying a
4311 host system triplet is preferable over using this. All the magic is
4312 done in the new `config.guess' script. Examine it for details.
4314 We have also brought our configure script much more in line with the FSF's
4315 version. It now supports the --with-xxx options. In particular,
4316 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4317 The resulting GDB will not be able to read arbitrary object file formats --
4318 only the format ``expected'' to be used on the configured target system.
4319 We hope to make this the default in a future release.
4321 * Documentation improvements
4323 There's new internal documentation on how to modify GDB, and how to
4324 produce clean changes to the code. We implore people to read it
4325 before submitting changes.
4327 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4328 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4329 `info' files are also provided. To build `info' files from scratch,
4330 you will need the latest `makeinfo' release, which will be available in
4331 a future texinfo-X.Y release.
4333 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4334 We're not sure exactly which versions have this problem, but it has
4335 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4336 or better. If that isn't possible, there is a patch in
4337 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4338 around this problem.
4342 GDB now supports array constants that can be used in expressions typed in by
4343 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4344 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4347 The new directory `gdb/sparclite' contains a program that demonstrates
4348 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4350 * New native hosts supported
4352 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4353 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4355 * New targets supported
4357 AMD 29k family via UDI a29k-amd-udi or udi29k
4359 * New file formats supported
4361 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4362 HPUX core files, and SCO 3.2v2 core files.
4366 Attaching to processes now works again; thanks for the many bug reports.
4368 We have also stomped on a bunch of core dumps caused by
4369 printf_filtered("%s") problems.
4371 We eliminated a copyright problem on the rpc and ptrace header files
4372 for VxWorks, which was discovered at the last minute during the 4.7
4373 release. You should now be able to build a VxWorks GDB.
4375 You can now interrupt gdb while an attached process is running. This
4376 will cause the attached process to stop, and give control back to GDB.
4378 We fixed problems caused by using too many file descriptors
4379 for reading symbols from object files and libraries. This was
4380 especially a problem for programs that used many (~100) shared
4383 The `step' command now only enters a subroutine if there is line number
4384 information for the subroutine. Otherwise it acts like the `next'
4385 command. Previously, `step' would enter subroutines if there was
4386 any debugging information about the routine. This avoids problems
4387 when using `cc -g1' on MIPS machines.
4389 * Internal improvements
4391 GDB's internal interfaces have been improved to make it easier to support
4392 debugging of multiple languages in the future.
4394 GDB now uses a common structure for symbol information internally.
4395 Minimal symbols (derived from linkage symbols in object files), partial
4396 symbols (from a quick scan of debug information), and full symbols
4397 contain a common subset of information, making it easier to write
4398 shared code that handles any of them.
4400 * New command line options
4402 We now accept --silent as an alias for --quiet.
4406 The memory-mapped-malloc library is now licensed under the GNU Library
4407 General Public License.
4409 *** Changes in GDB-4.7:
4411 * Host/native/target split
4413 GDB has had some major internal surgery to untangle the support for
4414 hosts and remote targets. Now, when you configure GDB for a remote
4415 target, it will no longer load in all of the support for debugging
4416 local programs on the host. When fully completed and tested, this will
4417 ensure that arbitrary host/target combinations are possible.
4419 The primary conceptual shift is to separate the non-portable code in
4420 GDB into three categories. Host specific code is required any time GDB
4421 is compiled on that host, regardless of the target. Target specific
4422 code relates to the peculiarities of the target, but can be compiled on
4423 any host. Native specific code is everything else: it can only be
4424 built when the host and target are the same system. Child process
4425 handling and core file support are two common `native' examples.
4427 GDB's use of /proc for controlling Unix child processes is now cleaner.
4428 It has been split out into a single module under the `target_ops' vector,
4429 plus two native-dependent functions for each system that uses /proc.
4431 * New hosts supported
4433 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4434 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4435 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4437 * New targets supported
4439 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4440 68030 and CPU32 m68030-*-*, m68332-*-*
4442 * New native hosts supported
4444 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4445 (386bsd is not well tested yet)
4446 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4448 * New file formats supported
4450 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4451 supports reading of `a.out.adobe' object files, which are an a.out
4452 format extended with minimal information about multiple sections.
4456 `show copying' is the same as the old `info copying'.
4457 `show warranty' is the same as `info warrantee'.
4458 These were renamed for consistency. The old commands continue to work.
4460 `info handle' is a new alias for `info signals'.
4462 You can now define pre-command hooks, which attach arbitrary command
4463 scripts to any command. The commands in the hook will be executed
4464 prior to the user's command. You can also create a hook which will be
4465 executed whenever the program stops. See gdb.texinfo.
4469 We now deal with Cfront style name mangling, and can even extract type
4470 info from mangled symbols. GDB can automatically figure out which
4471 symbol mangling style your C++ compiler uses.
4473 Calling of methods and virtual functions has been improved as well.
4477 The crash that occured when debugging Sun Ansi-C compiled binaries is
4478 fixed. This was due to mishandling of the extra N_SO stabs output
4481 We also finally got Ultrix 4.2 running in house, and fixed core file
4482 support, with help from a dozen people on the net.
4484 John M. Farrell discovered that the reason that single-stepping was so
4485 slow on all of the Mips based platforms (primarily SGI and DEC) was
4486 that we were trying to demangle and lookup a symbol used for internal
4487 purposes on every instruction that was being stepped through. Changing
4488 the name of that symbol so that it couldn't be mistaken for a C++
4489 mangled symbol sped things up a great deal.
4491 Rich Pixley sped up symbol lookups in general by getting much smarter
4492 about when C++ symbol mangling is necessary. This should make symbol
4493 completion (TAB on the command line) much faster. It's not as fast as
4494 we'd like, but it's significantly faster than gdb-4.6.
4498 A new user controllable variable 'call_scratch_address' can
4499 specify the location of a scratch area to be used when GDB
4500 calls a function in the target. This is necessary because the
4501 usual method of putting the scratch area on the stack does not work
4502 in systems that have separate instruction and data spaces.
4504 We integrated changes to support the 29k UDI (Universal Debugger
4505 Interface), but discovered at the last minute that we didn't have all
4506 of the appropriate copyright paperwork. We are working with AMD to
4507 resolve this, and hope to have it available soon.
4511 We have sped up the remote serial line protocol, especially for targets
4512 with lots of registers. It now supports a new `expedited status' ('T')
4513 message which can be used in place of the existing 'S' status message.
4514 This allows the remote stub to send only the registers that GDB
4515 needs to make a quick decision about single-stepping or conditional
4516 breakpoints, eliminating the need to fetch the entire register set for
4517 each instruction being stepped through.
4519 The GDB remote serial protocol now implements a write-through cache for
4520 registers, only re-reading the registers if the target has run.
4522 There is also a new remote serial stub for SPARC processors. You can
4523 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4524 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4525 processor with a serial port.
4529 Configure.in files have become much easier to read and modify. A new
4530 `table driven' format makes it more obvious what configurations are
4531 supported, and what files each one uses.
4535 There is a new opcodes library which will eventually contain all of the
4536 disassembly routines and opcode tables. At present, it only contains
4537 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4538 disassembler (binutils/objdump) to share these routines.
4540 The libiberty library is now copylefted under the GNU Library General
4541 Public License. This allows more liberal use, and was done so libg++
4542 can use it. This makes no difference to GDB, since the Library License
4543 grants all the rights from the General Public License.
4547 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4548 reference to the stabs symbol info used by the debugger. It is (as far
4549 as we know) the only published document on this fascinating topic. We
4550 encourage you to read it, compare it to the stabs information on your
4551 system, and send improvements on the document in general (to
4552 bug-gdb@prep.ai.mit.edu).
4554 And, of course, many bugs have been fixed.
4557 *** Changes in GDB-4.6:
4559 * Better support for C++ function names
4561 GDB now accepts as input the "demangled form" of C++ overloaded function
4562 names and member function names, and can do command completion on such names
4563 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4564 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4565 Make use of command completion, it is your friend.
4567 GDB also now accepts a variety of C++ mangled symbol formats. They are
4568 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4569 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4570 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4571 for the list of formats.
4573 * G++ symbol mangling problem
4575 Recent versions of gcc have a bug in how they emit debugging information for
4576 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4577 directory) can be applied to gcc to fix the problem. Alternatively, if you
4578 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4579 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4580 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4583 * New 'maintenance' command
4585 All of the commands related to hacking GDB internals have been moved out of
4586 the main command set, and now live behind the 'maintenance' command. This
4587 can also be abbreviated as 'mt'. The following changes were made:
4589 dump-me -> maintenance dump-me
4590 info all-breakpoints -> maintenance info breakpoints
4591 printmsyms -> maintenance print msyms
4592 printobjfiles -> maintenance print objfiles
4593 printpsyms -> maintenance print psymbols
4594 printsyms -> maintenance print symbols
4596 The following commands are new:
4598 maintenance demangle Call internal GDB demangler routine to
4599 demangle a C++ link name and prints the result.
4600 maintenance print type Print a type chain for a given symbol
4602 * Change to .gdbinit file processing
4604 We now read the $HOME/.gdbinit file before processing the argv arguments
4605 (e.g. reading symbol files or core files). This allows global parameters to
4606 be set, which will apply during the symbol reading. The ./.gdbinit is still
4607 read after argv processing.
4609 * New hosts supported
4611 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4613 GNU/Linux support i386-unknown-linux or linux
4615 We are also including code to support the HP/PA running BSD and HPUX. This
4616 is almost guaranteed not to work, as we didn't have time to test or build it
4617 for this release. We are including it so that the more adventurous (or
4618 masochistic) of you can play with it. We also had major problems with the
4619 fact that the compiler that we got from HP doesn't support the -g option.
4622 * New targets supported
4624 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4626 * More smarts about finding #include files
4628 GDB now remembers the compilation directory for all include files, and for
4629 all files from which C is generated (like yacc and lex sources). This
4630 greatly improves GDB's ability to find yacc/lex sources, and include files,
4631 especially if you are debugging your program from a directory different from
4632 the one that contains your sources.
4634 We also fixed a bug which caused difficulty with listing and setting
4635 breakpoints in include files which contain C code. (In the past, you had to
4636 try twice in order to list an include file that you hadn't looked at before.)
4638 * Interesting infernals change
4640 GDB now deals with arbitrary numbers of sections, where the symbols for each
4641 section must be relocated relative to that section's landing place in the
4642 target's address space. This work was needed to support ELF with embedded
4643 stabs used by Solaris-2.0.
4645 * Bug fixes (of course!)
4647 There have been loads of fixes for the following things:
4648 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4649 i960, stabs, DOS(GO32), procfs, etc...
4651 See the ChangeLog for details.
4653 *** Changes in GDB-4.5:
4655 * New machines supported (host and target)
4657 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4659 SGI Irix-4.x mips-sgi-irix4 or iris4
4661 * New malloc package
4663 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4664 Mmalloc is capable of handling mutiple heaps of memory. It is also
4665 capable of saving a heap to a file, and then mapping it back in later.
4666 This can be used to greatly speedup the startup of GDB by using a
4667 pre-parsed symbol table which lives in a mmalloc managed heap. For
4668 more details, please read mmalloc/mmalloc.texi.
4672 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4673 'help info proc' for details.
4675 * MIPS ecoff symbol table format
4677 The code that reads MIPS symbol table format is now supported on all hosts.
4678 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4681 * File name changes for MS-DOS
4683 Many files in the config directories have been renamed to make it easier to
4684 support GDB on MS-DOSe systems (which have very restrictive file name
4685 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4686 environment) is close to working but has some remaining problems. Note
4687 that debugging of DOS programs is not supported, due to limitations
4688 in the ``operating system'', but it can be used to host cross-debugging.
4690 * Cross byte order fixes
4692 Many fixes have been made to support cross debugging of Sparc and MIPS
4693 targets from hosts whose byte order differs.
4695 * New -mapped and -readnow options
4697 If memory-mapped files are available on your system through the 'mmap'
4698 system call, you can use the -mapped option on the `file' or
4699 `symbol-file' commands to cause GDB to write the symbols from your
4700 program into a reusable file. If the program you are debugging is
4701 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4702 Future GDB debugging sessions will notice the presence of this file,
4703 and will quickly map in symbol information from it, rather than reading
4704 the symbol table from the executable program. Using the '-mapped'
4705 option in a GDB `file' or `symbol-file' command has the same effect as
4706 starting GDB with the '-mapped' command-line option.
4708 You can cause GDB to read the entire symbol table immediately by using
4709 the '-readnow' option with any of the commands that load symbol table
4710 information (or on the GDB command line). This makes the command
4711 slower, but makes future operations faster.
4713 The -mapped and -readnow options are typically combined in order to
4714 build a `fred.syms' file that contains complete symbol information.
4715 A simple GDB invocation to do nothing but build a `.syms' file for future
4718 gdb -batch -nx -mapped -readnow programname
4720 The `.syms' file is specific to the host machine on which GDB is run.
4721 It holds an exact image of GDB's internal symbol table. It cannot be
4722 shared across multiple host platforms.
4724 * longjmp() handling
4726 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4727 siglongjmp() without losing control. This feature has not yet been ported to
4728 all systems. It currently works on many 386 platforms, all MIPS-based
4729 platforms (SGI, DECstation, etc), and Sun3/4.
4733 Preliminary work has been put in to support the new Solaris OS from Sun. At
4734 this time, it can control and debug processes, but it is not capable of
4739 As always, many many bug fixes. The major areas were with g++, and mipsread.
4740 People using the MIPS-based platforms should experience fewer mysterious
4741 crashes and trashed symbol tables.
4743 *** Changes in GDB-4.4:
4745 * New machines supported (host and target)
4747 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4749 BSD Reno on Vax vax-dec-bsd
4750 Ultrix on Vax vax-dec-ultrix
4752 * New machines supported (target)
4754 AMD 29000 embedded, using EBMON a29k-none-none
4758 GDB continues to improve its handling of C++. `References' work better.
4759 The demangler has also been improved, and now deals with symbols mangled as
4760 per the Annotated C++ Reference Guide.
4762 GDB also now handles `stabs' symbol information embedded in MIPS
4763 `ecoff' symbol tables. Since the ecoff format was not easily
4764 extensible to handle new languages such as C++, this appeared to be a
4765 good way to put C++ debugging info into MIPS binaries. This option
4766 will be supported in the GNU C compiler, version 2, when it is
4769 * New features for SVR4
4771 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4772 shared libraries. Debugging dynamically linked programs should present
4773 only minor differences from debugging statically linked programs.
4775 The `info proc' command will print out information about any process
4776 on an SVR4 system (including the one you are debugging). At the moment,
4777 it prints the address mappings of the process.
4779 If you bring up GDB on another SVR4 system, please send mail to
4780 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4782 * Better dynamic linking support in SunOS
4784 Reading symbols from shared libraries which contain debugging symbols
4785 now works properly. However, there remain issues such as automatic
4786 skipping of `transfer vector' code during function calls, which
4787 make it harder to debug code in a shared library, than to debug the
4788 same code linked statically.
4792 GDB is now using the latest `getopt' routines from the FSF. This
4793 version accepts the -- prefix for options with long names. GDB will
4794 continue to accept the old forms (-option and +option) as well.
4795 Various single letter abbreviations for options have been explicity
4796 added to the option table so that they won't get overshadowed in the
4797 future by other options that begin with the same letter.
4801 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4802 Many assorted bugs have been handled. Many more remain to be handled.
4803 See the various ChangeLog files (primarily in gdb and bfd) for details.
4806 *** Changes in GDB-4.3:
4808 * New machines supported (host and target)
4810 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4811 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4812 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4814 * Almost SCO Unix support
4816 We had hoped to support:
4817 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4818 (except for core file support), but we discovered very late in the release
4819 that it has problems with process groups that render gdb unusable. Sorry
4820 about that. I encourage people to fix it and post the fixes.
4822 * Preliminary ELF and DWARF support
4824 GDB can read ELF object files on System V Release 4, and can handle
4825 debugging records for C, in DWARF format, in ELF files. This support
4826 is preliminary. If you bring up GDB on another SVR4 system, please
4827 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4832 GDB now uses the latest `readline' library. One user-visible change
4833 is that two tabs will list possible command completions, which previously
4834 required typing M-? (meta-question mark, or ESC ?).
4838 The `stepi' bug that many of you noticed has been squashed.
4839 Many bugs in C++ have been handled. Many more remain to be handled.
4840 See the various ChangeLog files (primarily in gdb and bfd) for details.
4842 * State of the MIPS world (in case you wondered):
4844 GDB can understand the symbol tables emitted by the compilers
4845 supplied by most vendors of MIPS-based machines, including DEC. These
4846 symbol tables are in a format that essentially nobody else uses.
4848 Some versions of gcc come with an assembler post-processor called
4849 mips-tfile. This program is required if you want to do source-level
4850 debugging of gcc-compiled programs. I believe FSF does not ship
4851 mips-tfile with gcc version 1, but it will eventually come with gcc
4854 Debugging of g++ output remains a problem. g++ version 1.xx does not
4855 really support it at all. (If you're lucky, you should be able to get
4856 line numbers and stack traces to work, but no parameters or local
4857 variables.) With some work it should be possible to improve the
4860 When gcc version 2 is released, you will have somewhat better luck.
4861 However, even then you will get confusing results for inheritance and
4864 We will eventually provide full debugging of g++ output on
4865 DECstations. This will probably involve some kind of stabs-in-ecoff
4866 encapulation, but the details have not been worked out yet.
4869 *** Changes in GDB-4.2:
4871 * Improved configuration
4873 Only one copy of `configure' exists now, and it is not self-modifying.
4874 Porting BFD is simpler.
4878 The `step' and `next' commands now only stop at the first instruction
4879 of a source line. This prevents the multiple stops that used to occur
4880 in switch statements, for-loops, etc. `Step' continues to stop if a
4881 function that has debugging information is called within the line.
4885 Lots of small bugs fixed. More remain.
4887 * New host supported (not target)
4889 Intel 386 PC clone running Mach i386-none-mach
4892 *** Changes in GDB-4.1:
4894 * Multiple source language support
4896 GDB now has internal scaffolding to handle several source languages.
4897 It determines the type of each source file from its filename extension,
4898 and will switch expression parsing and number formatting to match the
4899 language of the function in the currently selected stack frame.
4900 You can also specifically set the language to be used, with
4901 `set language c' or `set language modula-2'.
4905 GDB now has preliminary support for the GNU Modula-2 compiler,
4906 currently under development at the State University of New York at
4907 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4908 continue through the fall of 1991 and into 1992.
4910 Other Modula-2 compilers are currently not supported, and attempting to
4911 debug programs compiled with them will likely result in an error as the
4912 symbol table is read. Feel free to work on it, though!
4914 There are hooks in GDB for strict type checking and range checking,
4915 in the `Modula-2 philosophy', but they do not currently work.
4919 GDB can now write to executable and core files (e.g. patch
4920 a variable's value). You must turn this switch on, specify
4921 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4922 by assigning a new value to a variable. Modifications take
4925 * Automatic SunOS shared library reading
4927 When you run your program, GDB automatically determines where its
4928 shared libraries (if any) have been loaded, and reads their symbols.
4929 The `share' command is no longer needed. This also works when
4930 examining core files.
4934 You can specify the number of lines that the `list' command shows.
4937 * New machines supported (host and target)
4939 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4940 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4941 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4943 * New hosts supported (not targets)
4945 IBM RT/PC: romp-ibm-aix or rtpc
4947 * New targets supported (not hosts)
4949 AMD 29000 embedded with COFF a29k-none-coff
4950 AMD 29000 embedded with a.out a29k-none-aout
4951 Ultracomputer remote kernel debug a29k-nyu-kern
4953 * New remote interfaces
4959 *** Changes in GDB-4.0:
4963 Wide output is wrapped at good places to make the output more readable.
4965 Gdb now supports cross-debugging from a host machine of one type to a
4966 target machine of another type. Communication with the target system
4967 is over serial lines. The ``target'' command handles connecting to the
4968 remote system; the ``load'' command will download a program into the
4969 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4970 also supports debugging of realtime processes running under VxWorks,
4971 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4972 stub on the target system.
4974 New CPUs supported include the AMD 29000 and Intel 960.
4976 GDB now reads object files and symbol tables via a ``binary file''
4977 library, which allows a single copy of GDB to debug programs of multiple
4978 object file types such as a.out and coff.
4980 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4981 refcard.dvi and refcard.ps are available to format it).
4984 * Control-Variable user interface simplified
4986 All variables that control the operation of the debugger can be set
4987 by the ``set'' command, and displayed by the ``show'' command.
4989 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4990 ``Show prompt'' produces the response:
4991 Gdb's prompt is new-gdb=>.
4993 What follows are the NEW set commands. The command ``help set'' will
4994 print a complete list of old and new set commands. ``help set FOO''
4995 will give a longer description of the variable FOO. ``show'' will show
4996 all of the variable descriptions and their current settings.
4998 confirm on/off: Enables warning questions for operations that are
4999 hard to recover from, e.g. rerunning the program while
5000 it is already running. Default is ON.
5002 editing on/off: Enables EMACS style command line editing
5003 of input. Previous lines can be recalled with
5004 control-P, the current line can be edited with control-B,
5005 you can search for commands with control-R, etc.
5008 history filename NAME: NAME is where the gdb command history
5009 will be stored. The default is .gdb_history,
5010 or the value of the environment variable
5013 history size N: The size, in commands, of the command history. The
5014 default is 256, or the value of the environment variable
5017 history save on/off: If this value is set to ON, the history file will
5018 be saved after exiting gdb. If set to OFF, the
5019 file will not be saved. The default is OFF.
5021 history expansion on/off: If this value is set to ON, then csh-like
5022 history expansion will be performed on
5023 command line input. The default is OFF.
5025 radix N: Sets the default radix for input and output. It can be set
5026 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5027 in the current radix, so "set radix 10" is always a no-op.
5029 height N: This integer value is the number of lines on a page. Default
5030 is 24, the current `stty rows'' setting, or the ``li#''
5031 setting from the termcap entry matching the environment
5034 width N: This integer value is the number of characters on a line.
5035 Default is 80, the current `stty cols'' setting, or the ``co#''
5036 setting from the termcap entry matching the environment
5039 Note: ``set screensize'' is obsolete. Use ``set height'' and
5040 ``set width'' instead.
5042 print address on/off: Print memory addresses in various command displays,
5043 such as stack traces and structure values. Gdb looks
5044 more ``symbolic'' if you turn this off; it looks more
5045 ``machine level'' with it on. Default is ON.
5047 print array on/off: Prettyprint arrays. New convenient format! Default
5050 print demangle on/off: Print C++ symbols in "source" form if on,
5053 print asm-demangle on/off: Same, for assembler level printouts
5056 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5059 * Support for Epoch Environment.
5061 The epoch environment is a version of Emacs v18 with windowing. One
5062 new command, ``inspect'', is identical to ``print'', except that if you
5063 are running in the epoch environment, the value is printed in its own
5067 * Support for Shared Libraries
5069 GDB can now debug programs and core files that use SunOS shared libraries.
5070 Symbols from a shared library cannot be referenced
5071 before the shared library has been linked with the program (this
5072 happens after you type ``run'' and before the function main() is entered).
5073 At any time after this linking (including when examining core files
5074 from dynamically linked programs), gdb reads the symbols from each
5075 shared library when you type the ``sharedlibrary'' command.
5076 It can be abbreviated ``share''.
5078 sharedlibrary REGEXP: Load shared object library symbols for files
5079 matching a unix regular expression. No argument
5080 indicates to load symbols for all shared libraries.
5082 info sharedlibrary: Status of loaded shared libraries.
5087 A watchpoint stops execution of a program whenever the value of an
5088 expression changes. Checking for this slows down execution
5089 tremendously whenever you are in the scope of the expression, but is
5090 quite useful for catching tough ``bit-spreader'' or pointer misuse
5091 problems. Some machines such as the 386 have hardware for doing this
5092 more quickly, and future versions of gdb will use this hardware.
5094 watch EXP: Set a watchpoint (breakpoint) for an expression.
5096 info watchpoints: Information about your watchpoints.
5098 delete N: Deletes watchpoint number N (same as breakpoints).
5099 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5100 enable N: Re-enables watchpoint number N (same as breakpoints).
5103 * C++ multiple inheritance
5105 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5108 * C++ exception handling
5110 Gdb now supports limited C++ exception handling. Besides the existing
5111 ability to breakpoint on an exception handler, gdb can breakpoint on
5112 the raising of an exception (before the stack is peeled back to the
5115 catch FOO: If there is a FOO exception handler in the dynamic scope,
5116 set a breakpoint to catch exceptions which may be raised there.
5117 Multiple exceptions (``catch foo bar baz'') may be caught.
5119 info catch: Lists all exceptions which may be caught in the
5120 current stack frame.
5123 * Minor command changes
5125 The command ``call func (arg, arg, ...)'' now acts like the print
5126 command, except it does not print or save a value if the function's result
5127 is void. This is similar to dbx usage.
5129 The ``up'' and ``down'' commands now always print the frame they end up
5130 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5131 frames without printing.
5133 * New directory command
5135 'dir' now adds directories to the FRONT of the source search path.
5136 The path starts off empty. Source files that contain debug information
5137 about the directory in which they were compiled can be found even
5138 with an empty path; Sun CC and GCC include this information. If GDB can't
5139 find your source file in the current directory, type "dir .".
5141 * Configuring GDB for compilation
5143 For normal use, type ``./configure host''. See README or gdb.texinfo
5146 GDB now handles cross debugging. If you are remotely debugging between
5147 two different machines, type ``./configure host -target=targ''.
5148 Host is the machine where GDB will run; targ is the machine
5149 where the program that you are debugging will run.