1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
6 * The "info os" command on GNU/Linux can now display information on
7 several new classes of objects managed by the operating system:
8 "info os procgroups" lists process groups
9 "info os files" lists file descriptors
10 "info os sockets" lists internet-domain sockets
11 "info os shm" lists shared-memory regions
12 "info os semaphores" lists semaphores
13 "info os msg" lists message queues
14 "info os modules" lists loaded kernel modules
16 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
17 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
18 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
19 options and inspect the probe arguments using the new $_probe_arg family
20 of convenience variables. You can obtain more information about SystemTap
21 in <http://sourceware.org/systemtap/>.
23 * GDB now supports reversible debugging on ARM, it allows you to
24 debug basic ARM and THUMB instructions, and provides
25 record/replay support.
27 * The option "symbol-reloading" has been deleted as it is no longer used.
31 ** GDB commands implemented in Python can now be put in command class
34 ** The "maint set python print-stack on|off" is now deleted.
36 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
37 apply "flag enum"-style pretty-printing to any enum.
39 ** gdb.lookup_symbol can now work when there is no current frame.
41 ** gdb.Symbol now has a 'line' attribute, holding the line number in
42 the source at which the symbol was defined.
44 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
45 method 'value'. The former indicates whether the symbol needs a
46 frame in order to compute its value, and the latter computes the
49 ** A new method 'referenced_value' on gdb.Value objects which can
50 dereference pointer as well as C++ reference values.
52 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
53 which return the global and static blocks (as gdb.Block objects),
54 of the underlying symbol table, respectively.
56 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
57 object associated with a PC value.
59 * Go language support.
60 GDB now supports debugging programs written in the Go programming
63 * GDBserver now supports stdio connections.
64 E.g. (gdb) target remote | ssh myhost gdbserver - hello
66 * The binary "gdbtui" can no longer be built or installed.
67 Use "gdb -tui" instead.
69 * GDB will now print "flag" enums specially. A flag enum is one where
70 all the enumerator values have no bits in common when pairwise
71 "and"ed. When printing a value whose type is a flag enum, GDB will
72 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
73 (gdb) print (enum E) 3
76 * The filename part of a linespec will now match trailing components
77 of a source file name. For example, "break gcc/expr.c:1000" will
78 now set a breakpoint in build/gcc/expr.c, but not
81 * The "info proc" and "generate-core-file" commands will now also
82 work on remote targets connected to GDBserver on Linux.
84 * The command "info catch" has been removed. It has been disabled
87 * The "catch exception" and "catch assert" commands now accept
88 a condition at the end of the command, much like the "break"
89 command does. For instance:
91 (gdb) catch exception Constraint_Error if Barrier = True
93 Previously, it was possible to add a condition to such catchpoints,
94 but it had to be done as a second step, after the catchpoint had been
95 created, using the "condition" command.
97 * The "info static-tracepoint-marker" command will now also work on
98 native Linux targets with in-process agent.
100 * GDB can now set breakpoints on inlined functions.
102 * The .gdb_index section has been updated to include symbols for
103 inlined functions. GDB will ignore older .gdb_index sections by
104 default, which could cause symbol files to be loaded more slowly
105 until their .gdb_index sections can be recreated. The new option
106 --use-deprecated-index-sections will cause GDB to use any older
107 .gdb_index sections it finds. This will restore performance, but
108 the ability to set breakpoints on inlined functions will be lost
109 in symbol files with older .gdb_index sections.
111 * Ada support for GDB/MI Variable Objects has been added.
113 * GDB can now support 'breakpoint always-inserted mode' in 'record'
118 ** "catch load" and "catch unload" can be used to stop when a shared
119 library is loaded or unloaded, respectively.
121 ** "enable count" can be used to auto-disable a breakpoint after
124 ** "info vtbl" can be used to show the virtual method tables for
125 C++ and Java objects.
127 ** "explore" and its sub commands "explore value" and "explore type"
128 can be used to reccursively explore values and types of
129 expressions. These commands are available only if GDB is
130 configured with '--with-python'.
132 ** "info auto-load" shows status of all kinds of auto-loaded files,
133 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
134 sequences of commands files, "info auto-load python-scripts"
135 shows status of auto-loading Python script files,
136 "info auto-load local-gdbinit" shows status of loading init file
137 (.gdbinit) from current directory and "info auto-load libthread-db" shows
138 status of inferior specific thread debugging shared library loading.
140 ** "info auto-load-scripts", "set auto-load-scripts on|off"
141 and "show auto-load-scripts" commands have been deprecated, use their
142 "info auto-load python-scripts", "set auto-load python-scripts on|off"
143 and "show auto-load python-scripts" counterparts instead.
145 ** "dprintf location,format,args..." creates a dynamic printf, which
146 is basically a breakpoint that does a printf and immediately
147 resumes your program's execution, so it is like a printf that you
148 can insert dynamically at runtime instead of at compiletime.
152 Renesas RL78 rl78-*-elf
153 HP OpenVMS ia64 ia64-hp-openvms*
155 * GDBserver supports evaluation of breakpoint conditions. When
156 support is advertised by GDBserver, GDB may be told to send the
157 breakpoint conditions in bytecode form to GDBserver. GDBserver
158 will only report the breakpoint trigger to GDB when its condition
163 set breakpoint condition-evaluation
164 show breakpoint condition-evaluation
165 Control whether breakpoint conditions are evaluated by GDB ("host") or by
166 GDBserver ("target"). Default option "auto" chooses the most efficient
168 This option can improve debugger efficiency depending on the speed of the
172 Disable auto-loading globally.
175 Show auto-loading setting of all kinds of auto-loaded files.
177 set auto-load gdb-scripts on|off
178 show auto-load gdb-scripts
179 Control auto-loading of GDB canned sequences of commands files.
181 set auto-load python-scripts on|off
182 show auto-load python-scripts
183 Control auto-loading of Python script files.
185 set auto-load local-gdbinit on|off
186 show auto-load local-gdbinit
187 Control loading of init file (.gdbinit) from current directory.
189 set auto-load libthread-db on|off
190 show auto-load libthread-db
191 Control auto-loading of inferior specific thread debugging shared library.
193 set auto-load scripts-directory <dir1>[:<dir2>...]
194 show auto-load scripts-directory
195 Set a list of directories from which to load auto-loaded scripts.
196 Automatically loaded Python scripts and GDB scripts are located in one
197 of the directories listed by this option.
198 The delimiter (':' above) may differ according to the host platform.
200 set auto-load safe-path <dir1>[:<dir2>...]
201 show auto-load safe-path
202 Set a list of directories from which it is safe to auto-load files.
203 The delimiter (':' above) may differ according to the host platform.
205 set debug auto-load on|off
207 Control display of debugging info for auto-loading the files above.
209 set dprintf-style gdb|call
211 Control the way in which a dynamic printf is performed; "gdb" requests
212 a GDB printf command, while "call" causes dprintf to call a function
215 set dprintf-function <expr>
216 show dprintf-function
217 set dprintf-channel <expr>
219 Set the function and optional first argument to the call when using
220 the "call" style of dynamic printf.
222 * New configure options
225 Configure default value for the 'set auto-load scripts-directory'
226 setting above. It defaults to '$ddir/auto-load', $ddir representing
227 GDB's data directory (available via show data-directory).
229 --with-auto-load-safe-path
230 Configure default value for the 'set auto-load safe-path' setting
231 above. It defaults to the --with-auto-load-dir setting.
233 --without-auto-load-safe-path
234 Set 'set auto-load safe-path' to '/', effectively disabling this
239 z0/z1 conditional breakpoints extension
241 The z0/z1 breakpoint insertion packets have been extended to carry
242 a list of conditional expressions over to the remote stub depending on the
243 condition evaluation mode. The use of this extension can be controlled
244 via the "set remote conditional-breakpoints-packet" command.
248 Specify the signals which the remote stub may pass to the debugged
249 program without GDB involvement.
251 * New command line options
253 --init-command=FILE, -ix Like --command, -x but execute it
254 before loading inferior.
255 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
256 execute it before loading inferior.
258 *** Changes in GDB 7.4
260 * GDB now handles ambiguous linespecs more consistently; the existing
261 FILE:LINE support has been expanded to other types of linespecs. A
262 breakpoint will now be set on all matching locations in all
263 inferiors, and locations will be added or removed according to
266 * GDB now allows you to skip uninteresting functions and files when
267 stepping with the "skip function" and "skip file" commands.
269 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
270 and "show remote hardware-watchpoint-length-limit". These allows to
271 set or show the maximum length limit (in bytes) of a remote
272 target hardware watchpoint.
274 This allows e.g. to use "unlimited" hardware watchpoints with the
275 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
276 watchpoints are slower than real hardware watchpoints but are
277 significantly faster than gdb software watchpoints.
281 ** The register_pretty_printer function in module gdb.printing now takes
282 an optional `replace' argument. If True, the new printer replaces any
285 ** The "maint set python print-stack on|off" command has been
286 deprecated and will be deleted in GDB 7.5.
287 A new command: "set python print-stack none|full|message" has
288 replaced it. Additionally, the default for "print-stack" is
289 now "message", which just prints the error message without
292 ** A prompt substitution hook (prompt_hook) is now available to the
295 ** A new Python module, gdb.prompt has been added to the GDB Python
296 modules library. This module provides functionality for
297 escape sequences in prompts (used by set/show
298 extended-prompt). These escape sequences are replaced by their
301 ** Python commands and convenience-functions located in
302 'data-directory'/python/gdb/command and
303 'data-directory'/python/gdb/function are now automatically loaded
306 ** Blocks now provide four new attributes. global_block and
307 static_block will return the global and static blocks
308 respectively. is_static and is_global are boolean attributes
309 that indicate if the block is one of those two types.
311 ** Symbols now provide the "type" attribute, the type of the symbol.
313 ** The "gdb.breakpoint" function has been deprecated in favor of
316 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
317 of a function. This class is based on the "finish" command
318 available in the CLI.
320 ** Type objects for struct and union types now allow access to
321 the fields using standard Python dictionary (mapping) methods.
322 For example, "some_type['myfield']" now works, as does
325 ** A new event "gdb.new_objfile" has been added, triggered by loading a
328 ** A new function, "deep_items" has been added to the gdb.types
329 module in the GDB Python modules library. This function returns
330 an iterator over the fields of a struct or union type. Unlike
331 the standard Python "iteritems" method, it will recursively traverse
332 any anonymous fields.
336 ** "*stopped" events can report several new "reason"s, such as
339 ** Breakpoint changes are now notified using new async records, like
340 "=breakpoint-modified".
342 ** New command -ada-task-info.
344 * libthread-db-search-path now supports two special values: $sdir and $pdir.
345 $sdir specifies the default system locations of shared libraries.
346 $pdir specifies the directory where the libpthread used by the application
349 GDB no longer looks in $sdir and $pdir after it has searched the directories
350 mentioned in libthread-db-search-path. If you want to search those
351 directories, they must be specified in libthread-db-search-path.
352 The default value of libthread-db-search-path on GNU/Linux and Solaris
353 systems is now "$sdir:$pdir".
355 $pdir is not supported by gdbserver, it is currently ignored.
356 $sdir is supported by gdbserver.
358 * New configure option --with-iconv-bin.
359 When using the internationalization support like the one in the GNU C
360 library, GDB will invoke the "iconv" program to get a list of supported
361 character sets. If this program lives in a non-standard location, one can
362 use this option to specify where to find it.
364 * When natively debugging programs on PowerPC BookE processors running
365 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
366 watchpoints, which specify a mask in addition to an address to watch.
367 The mask specifies that some bits of an address (the bits which are
368 reset in the mask) should be ignored when matching the address accessed
369 by the inferior against the watchpoint address. See the "PowerPC Embedded"
370 section in the user manual for more details.
372 * The new option --once causes GDBserver to stop listening for connections once
373 the first connection is made. The listening port used by GDBserver will
374 become available after that.
376 * New commands "info macros" and "alias" have been added.
378 * New function parameters suffix @entry specifies value of function parameter
379 at the time the function got called. Entry values are available only since
385 "!" is now an alias of the "shell" command.
386 Note that no space is needed between "!" and SHELL COMMAND.
390 watch EXPRESSION mask MASK_VALUE
391 The watch command now supports the mask argument which allows creation
392 of masked watchpoints, if the current architecture supports this feature.
394 info auto-load-scripts [REGEXP]
395 This command was formerly named "maintenance print section-scripts".
396 It is now generally useful and is no longer a maintenance-only command.
398 info macro [-all] [--] MACRO
399 The info macro command has new options `-all' and `--'. The first for
400 printing all definitions of a macro. The second for explicitly specifying
401 the end of arguments and the beginning of the macro name in case the macro
402 name starts with a hyphen.
404 collect[/s] EXPRESSIONS
405 The tracepoint collect command now takes an optional modifier "/s"
406 that directs it to dereference pointer-to-character types and
407 collect the bytes of memory up to a zero byte. The behavior is
408 similar to what you see when you use the regular print command on a
409 string. An optional integer following the "/s" sets a bound on the
410 number of bytes that will be collected.
413 The trace start command now interprets any supplied arguments as a
414 note to be recorded with the trace run, with an effect similar to
415 setting the variable trace-notes.
418 The trace stop command now interprets any arguments as a note to be
419 mentioned along with the tstatus report that the trace was stopped
420 with a command. The effect is similar to setting the variable
423 * Tracepoints can now be enabled and disabled at any time after a trace
424 experiment has been started using the standard "enable" and "disable"
425 commands. It is now possible to start a trace experiment with no enabled
426 tracepoints; GDB will display a warning, but will allow the experiment to
427 begin, assuming that tracepoints will be enabled as needed while the trace
430 * Fast tracepoints on 32-bit x86-architectures can now be placed at
431 locations with 4-byte instructions, when they were previously
432 limited to locations with instructions of 5 bytes or longer.
438 Set the GDB prompt, and allow escape sequences to be inserted to
439 display miscellaneous information (see 'help set extended-prompt'
440 for the list of sequences). This prompt (and any information
441 accessed through the escape sequences) is updated every time the
444 set print entry-values (both|compact|default|if-needed|no|only|preferred)
445 show print entry-values
446 Set printing of frame argument values at function entry. In some cases
447 GDB can determine the value of function argument which was passed by the
448 function caller, even if the value was modified inside the called function.
450 set debug entry-values
451 show debug entry-values
452 Control display of debugging info for determining frame argument values at
453 function entry and virtual tail call frames.
455 set basenames-may-differ
456 show basenames-may-differ
457 Set whether a source file may have multiple base names.
458 (A "base name" is the name of a file with the directory part removed.
459 Example: The base name of "/home/user/hello.c" is "hello.c".)
460 If set, GDB will canonicalize file names (e.g., expand symlinks)
461 before comparing them. Canonicalization is an expensive operation,
462 but it allows the same file be known by more than one base name.
463 If not set (the default), all source files are assumed to have just
464 one base name, and gdb will do file name comparisons more efficiently.
470 Set a user name and notes for the current and any future trace runs.
471 This is useful for long-running and/or disconnected traces, to
472 inform others (or yourself) as to who is running the trace, supply
473 contact information, or otherwise explain what is going on.
476 show trace-stop-notes
477 Set a note attached to the trace run, that is displayed when the
478 trace has been stopped by a tstop command. This is useful for
479 instance as an explanation, if you are stopping a trace run that was
480 started by someone else.
486 Dynamically enable a tracepoint in a started trace experiment.
490 Dynamically disable a tracepoint in a started trace experiment.
494 Set the user and notes of the trace run.
498 Query the current status of a tracepoint.
502 Query the minimum length of instruction at which a fast tracepoint may
505 * Dcache size (number of lines) and line-size are now runtime-configurable
506 via "set dcache line" and "set dcache line-size" commands.
510 Texas Instruments TMS320C6x tic6x-*-*
514 Renesas RL78 rl78-*-elf
516 *** Changes in GDB 7.3.1
518 * The build failure for NetBSD and OpenBSD targets have now been fixed.
520 *** Changes in GDB 7.3
522 * GDB has a new command: "thread find [REGEXP]".
523 It finds the thread id whose name, target id, or thread extra info
524 matches the given regular expression.
526 * The "catch syscall" command now works on mips*-linux* targets.
528 * The -data-disassemble MI command now supports modes 2 and 3 for
529 dumping the instruction opcodes.
531 * New command line options
533 -data-directory DIR Specify DIR as the "data-directory".
534 This is mostly for testing purposes.
536 * The "maint set python auto-load on|off" command has been renamed to
537 "set auto-load-scripts on|off".
539 * GDB has a new command: "set directories".
540 It is like the "dir" command except that it replaces the
541 source path list instead of augmenting it.
543 * GDB now understands thread names.
545 On GNU/Linux, "info threads" will display the thread name as set by
546 prctl or pthread_setname_np.
548 There is also a new command, "thread name", which can be used to
549 assign a name internally for GDB to display.
552 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
553 has been integrated into GDB.
557 ** The function gdb.Write now accepts an optional keyword 'stream'.
558 This keyword, when provided, will direct the output to either
559 stdout, stderr, or GDB's logging output.
561 ** Parameters can now be be sub-classed in Python, and in particular
562 you may implement the get_set_doc and get_show_doc functions.
563 This improves how Parameter set/show documentation is processed
564 and allows for more dynamic content.
566 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
567 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
568 have an is_valid method.
570 ** Breakpoints can now be sub-classed in Python, and in particular
571 you may implement a 'stop' function that is executed each time
572 the inferior reaches that breakpoint.
574 ** New function gdb.lookup_global_symbol looks up a global symbol.
576 ** GDB values in Python are now callable if the value represents a
577 function. For example, if 'some_value' represents a function that
578 takes two integer parameters and returns a value, you can call
579 that function like so:
581 result = some_value (10,20)
583 ** Module gdb.types has been added.
584 It contains a collection of utilities for working with gdb.Types objects:
585 get_basic_type, has_field, make_enum_dict.
587 ** Module gdb.printing has been added.
588 It contains utilities for writing and registering pretty-printers.
589 New classes: PrettyPrinter, SubPrettyPrinter,
590 RegexpCollectionPrettyPrinter.
591 New function: register_pretty_printer.
593 ** New commands "info pretty-printers", "enable pretty-printer" and
594 "disable pretty-printer" have been added.
596 ** gdb.parameter("directories") is now available.
598 ** New function gdb.newest_frame returns the newest frame in the
601 ** The gdb.InferiorThread class has a new "name" attribute. This
602 holds the thread's name.
604 ** Python Support for Inferior events.
605 Python scripts can add observers to be notified of events
606 occurring in the process being debugged.
607 The following events are currently supported:
608 - gdb.events.cont Continue event.
609 - gdb.events.exited Inferior exited event.
610 - gdb.events.stop Signal received, and Breakpoint hit events.
614 ** GDB now puts template parameters in scope when debugging in an
615 instantiation. For example, if you have:
617 template<int X> int func (void) { return X; }
619 then if you step into func<5>, "print X" will show "5". This
620 feature requires proper debuginfo support from the compiler; it
621 was added to GCC 4.5.
623 ** The motion commands "next", "finish", "until", and "advance" now
624 work better when exceptions are thrown. In particular, GDB will
625 no longer lose control of the inferior; instead, the GDB will
626 stop the inferior at the point at which the exception is caught.
627 This functionality requires a change in the exception handling
628 code that was introduced in GCC 4.5.
630 * GDB now follows GCC's rules on accessing volatile objects when
631 reading or writing target state during expression evaluation.
632 One notable difference to prior behavior is that "print x = 0"
633 no longer generates a read of x; the value of the assignment is
634 now always taken directly from the value being assigned.
636 * GDB now has some support for using labels in the program's source in
637 linespecs. For instance, you can use "advance label" to continue
638 execution to a label.
640 * GDB now has support for reading and writing a new .gdb_index
641 section. This section holds a fast index of DWARF debugging
642 information and can be used to greatly speed up GDB startup and
643 operation. See the documentation for `save gdb-index' for details.
645 * The "watch" command now accepts an optional "-location" argument.
646 When used, this causes GDB to watch the memory referred to by the
647 expression. Such a watchpoint is never deleted due to it going out
650 * GDB now supports thread debugging of core dumps on GNU/Linux.
652 GDB now activates thread debugging using the libthread_db library
653 when debugging GNU/Linux core dumps, similarly to when debugging
654 live processes. As a result, when debugging a core dump file, GDB
655 is now able to display pthread_t ids of threads. For example, "info
656 threads" shows the same output as when debugging the process when it
657 was live. In earlier releases, you'd see something like this:
660 * 1 LWP 6780 main () at main.c:10
662 While now you see this:
665 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
667 It is also now possible to inspect TLS variables when debugging core
670 When debugging a core dump generated on a machine other than the one
671 used to run GDB, you may need to point GDB at the correct
672 libthread_db library with the "set libthread-db-search-path"
673 command. See the user manual for more details on this command.
675 * When natively debugging programs on PowerPC BookE processors running
676 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
677 which stop execution of the inferior whenever it executes an instruction
678 at any address within the specified range. See the "PowerPC Embedded"
679 section in the user manual for more details.
681 * New features in the GDB remote stub, GDBserver
683 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
684 and i686 LynxOS (version 5.x).
686 ** GDBserver is now supported on Blackfin Linux.
688 * New native configurations
690 ia64 HP-UX ia64-*-hpux*
694 Analog Devices, Inc. Blackfin Processor bfin-*
696 * Ada task switching is now supported on sparc-elf targets when
697 debugging a program using the Ravenscar Profile. For more information,
698 see the "Tasking Support when using the Ravenscar Profile" section
699 in the GDB user manual.
701 * Guile support was removed.
703 * New features in the GNU simulator
705 ** The --map-info flag lists all known core mappings.
707 ** CFI flashes may be simulated via the "cfi" device.
709 *** Changes in GDB 7.2
711 * Shared library support for remote targets by default
713 When GDB is configured for a generic, non-OS specific target, like
714 for example, --target=arm-eabi or one of the many *-*-elf targets,
715 GDB now queries remote stubs for loaded shared libraries using the
716 `qXfer:libraries:read' packet. Previously, shared library support
717 was always disabled for such configurations.
721 ** Argument Dependent Lookup (ADL)
723 In C++ ADL lookup directs function search to the namespaces of its
724 arguments even if the namespace has not been imported.
734 Here the compiler will search for `foo' in the namespace of 'b'
735 and find A::foo. GDB now supports this. This construct is commonly
736 used in the Standard Template Library for operators.
738 ** Improved User Defined Operator Support
740 In addition to member operators, GDB now supports lookup of operators
741 defined in a namespace and imported with a `using' directive, operators
742 defined in the global scope, operators imported implicitly from an
743 anonymous namespace, and the ADL operators mentioned in the previous
745 GDB now also supports proper overload resolution for all the previously
746 mentioned flavors of operators.
748 ** static const class members
750 Printing of static const class members that are initialized in the
751 class definition has been fixed.
753 * Windows Thread Information Block access.
755 On Windows targets, GDB now supports displaying the Windows Thread
756 Information Block (TIB) structure. This structure is visible either
757 by using the new command `info w32 thread-information-block' or, by
758 dereferencing the new convenience variable named `$_tlb', a
759 thread-specific pointer to the TIB. This feature is also supported
760 when remote debugging using GDBserver.
764 Static tracepoints are calls in the user program into a tracing
765 library. One such library is a port of the LTTng kernel tracer to
766 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
767 When debugging with GDBserver, GDB now supports combining the GDB
768 tracepoint machinery with such libraries. For example: the user can
769 use GDB to probe a static tracepoint marker (a call from the user
770 program into the tracing library) with the new "strace" command (see
771 "New commands" below). This creates a "static tracepoint" in the
772 breakpoint list, that can be manipulated with the same feature set
773 as fast and regular tracepoints. E.g., collect registers, local and
774 global variables, collect trace state variables, and define
775 tracepoint conditions. In addition, the user can collect extra
776 static tracepoint marker specific data, by collecting the new
777 $_sdata internal variable. When analyzing the trace buffer, you can
778 inspect $_sdata like any other variable available to GDB. For more
779 information, see the "Tracepoints" chapter in GDB user manual. New
780 remote packets have been defined to support static tracepoints, see
781 the "New remote packets" section below.
783 * Better reconstruction of tracepoints after disconnected tracing
785 GDB will attempt to download the original source form of tracepoint
786 definitions when starting a trace run, and then will upload these
787 upon reconnection to the target, resulting in a more accurate
788 reconstruction of the tracepoints that are in use on the target.
792 You can now exercise direct control over the ways that GDB can
793 affect your program. For instance, you can disallow the setting of
794 breakpoints, so that the program can run continuously (assuming
795 non-stop mode). In addition, the "observer" variable is available
796 to switch all of the different controls; in observer mode, GDB
797 cannot affect the target's behavior at all, which is useful for
798 tasks like diagnosing live systems in the field.
800 * The new convenience variable $_thread holds the number of the
807 Return the address of the Windows Thread Information Block of a given thread.
811 In response to several of the tracepoint packets, the target may now
812 also respond with a number of intermediate `qRelocInsn' request
813 packets before the final result packet, to have GDB handle
814 relocating an instruction to execute at a different address. This
815 is particularly useful for stubs that support fast tracepoints. GDB
816 reports support for this feature in the qSupported packet.
820 List static tracepoint markers in the target program.
824 List static tracepoint markers at a given address in the target
827 qXfer:statictrace:read
829 Read the static trace data collected (by a `collect $_sdata'
830 tracepoint action). The remote stub reports support for this packet
831 to gdb's qSupported query.
835 Send the current settings of GDB's permission flags.
839 Send part of the source (textual) form of a tracepoint definition,
840 which includes location, conditional, and action list.
842 * The source command now accepts a -s option to force searching for the
843 script in the source search path even if the script name specifies
846 * New features in the GDB remote stub, GDBserver
848 - GDBserver now support tracepoints (including fast tracepoints, and
849 static tracepoints). The feature is currently supported by the
850 i386-linux and amd64-linux builds. See the "Tracepoints support
851 in gdbserver" section in the manual for more information.
853 GDBserver JIT compiles the tracepoint's conditional agent
854 expression bytecode into native code whenever possible for low
855 overhead dynamic tracepoints conditionals. For such tracepoints,
856 an expression that examines program state is evaluated when the
857 tracepoint is reached, in order to determine whether to capture
858 trace data. If the condition is simple and false, processing the
859 tracepoint finishes very quickly and no data is gathered.
861 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
862 for static tracepoints support.
864 - GDBserver now supports x86_64 Windows 64-bit debugging.
866 * GDB now sends xmlRegisters= in qSupported packet to indicate that
867 it understands register description.
869 * The --batch flag now disables pagination and queries.
871 * X86 general purpose registers
873 GDB now supports reading/writing byte, word and double-word x86
874 general purpose registers directly. This means you can use, say,
875 $ah or $ax to refer, respectively, to the byte register AH and
876 16-bit word register AX that are actually portions of the 32-bit
877 register EAX or 64-bit register RAX.
879 * The `commands' command now accepts a range of breakpoints to modify.
880 A plain `commands' following a command that creates multiple
881 breakpoints affects all the breakpoints set by that command. This
882 applies to breakpoints set by `rbreak', and also applies when a
883 single `break' command creates multiple breakpoints (e.g.,
884 breakpoints on overloaded c++ functions).
886 * The `rbreak' command now accepts a filename specification as part of
887 its argument, limiting the functions selected by the regex to those
888 in the specified file.
890 * Support for remote debugging Windows and SymbianOS shared libraries
891 from Unix hosts has been improved. Non Windows GDB builds now can
892 understand target reported file names that follow MS-DOS based file
893 system semantics, such as file names that include drive letters and
894 use the backslash character as directory separator. This makes it
895 possible to transparently use the "set sysroot" and "set
896 solib-search-path" on Unix hosts to point as host copies of the
897 target's shared libraries. See the new command "set
898 target-file-system-kind" described below, and the "Commands to
899 specify files" section in the user manual for more information.
903 eval template, expressions...
904 Convert the values of one or more expressions under the control
905 of the string template to a command line, and call it.
907 set target-file-system-kind unix|dos-based|auto
908 show target-file-system-kind
909 Set or show the assumed file system kind for target reported file
912 save breakpoints <filename>
913 Save all current breakpoint definitions to a file suitable for use
914 in a later debugging session. To read the saved breakpoint
915 definitions, use the `source' command.
917 `save tracepoints' is a new alias for `save-tracepoints'. The latter
920 info static-tracepoint-markers
921 Display information about static tracepoint markers in the target.
923 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
924 Define a static tracepoint by probing a marker at the given
925 function, line, address, or marker ID.
929 Enable and disable observer mode.
931 set may-write-registers on|off
932 set may-write-memory on|off
933 set may-insert-breakpoints on|off
934 set may-insert-tracepoints on|off
935 set may-insert-fast-tracepoints on|off
936 set may-interrupt on|off
937 Set individual permissions for GDB effects on the target. Note that
938 some of these settings can have undesirable or surprising
939 consequences, particularly when changed in the middle of a session.
940 For instance, disabling the writing of memory can prevent
941 breakpoints from being inserted, cause single-stepping to fail, or
942 even crash your program, if you disable after breakpoints have been
943 inserted. However, GDB should not crash.
945 set record memory-query on|off
946 show record memory-query
947 Control whether to stop the inferior if memory changes caused
948 by an instruction cannot be recorded.
953 The disassemble command now supports "start,+length" form of two arguments.
957 ** GDB now provides a new directory location, called the python directory,
958 where Python scripts written for GDB can be installed. The location
959 of that directory is <data-directory>/python, where <data-directory>
960 is the GDB data directory. For more details, see section `Scripting
961 GDB using Python' in the manual.
963 ** The GDB Python API now has access to breakpoints, symbols, symbol
964 tables, program spaces, inferiors, threads and frame's code blocks.
965 Additionally, GDB Parameters can now be created from the API, and
966 manipulated via set/show in the CLI.
968 ** New functions gdb.target_charset, gdb.target_wide_charset,
969 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
971 ** New exception gdb.GdbError.
973 ** Pretty-printers are now also looked up in the current program space.
975 ** Pretty-printers can now be individually enabled and disabled.
977 ** GDB now looks for names of Python scripts to auto-load in a
978 special section named `.debug_gdb_scripts', in addition to looking
979 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
981 * Tracepoint actions were unified with breakpoint commands. In particular,
982 there are no longer differences in "info break" output for breakpoints and
983 tracepoints and the "commands" command can be used for both tracepoints and
988 ARM Symbian arm*-*-symbianelf*
990 * D language support.
991 GDB now supports debugging programs written in the D programming
994 * GDB now supports the extended ptrace interface for PowerPC which is
995 available since Linux kernel version 2.6.34. This automatically enables
996 any hardware breakpoints and additional hardware watchpoints available in
997 the processor. The old ptrace interface exposes just one hardware
998 watchpoint and no hardware breakpoints.
1000 * GDB is now able to use the Data Value Compare (DVC) register available on
1001 embedded PowerPC processors to implement in hardware simple watchpoint
1002 conditions of the form:
1004 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1006 This works in native GDB running on Linux kernels with the extended ptrace
1007 interface mentioned above.
1009 *** Changes in GDB 7.1
1013 ** Namespace Support
1015 GDB now supports importing of namespaces in C++. This enables the
1016 user to inspect variables from imported namespaces. Support for
1017 namepace aliasing has also been added. So, if a namespace is
1018 aliased in the current scope (e.g. namepace C=A; ) the user can
1019 print variables using the alias (e.g. (gdb) print C::x).
1023 All known bugs relating to the printing of virtual base class were
1024 fixed. It is now possible to call overloaded static methods using a
1029 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1030 and reinterpret_cast<> are now handled by the C++ expression parser.
1034 Xilinx MicroBlaze microblaze-*-*
1039 Xilinx MicroBlaze microblaze
1042 * Multi-program debugging.
1044 GDB now has support for multi-program (a.k.a. multi-executable or
1045 multi-exec) debugging. This allows for debugging multiple inferiors
1046 simultaneously each running a different program under the same GDB
1047 session. See "Debugging Multiple Inferiors and Programs" in the
1048 manual for more information. This implied some user visible changes
1049 in the multi-inferior support. For example, "info inferiors" now
1050 lists inferiors that are not running yet or that have exited
1051 already. See also "New commands" and "New options" below.
1053 * New tracing features
1055 GDB's tracepoint facility now includes several new features:
1057 ** Trace state variables
1059 GDB tracepoints now include support for trace state variables, which
1060 are variables managed by the target agent during a tracing
1061 experiment. They are useful for tracepoints that trigger each
1062 other, so for instance one tracepoint can count hits in a variable,
1063 and then a second tracepoint has a condition that is true when the
1064 count reaches a particular value. Trace state variables share the
1065 $-syntax of GDB convenience variables, and can appear in both
1066 tracepoint actions and condition expressions. Use the "tvariable"
1067 command to create, and "info tvariables" to view; see "Trace State
1068 Variables" in the manual for more detail.
1072 GDB now includes an option for defining fast tracepoints, which
1073 targets may implement more efficiently, such as by installing a jump
1074 into the target agent rather than a trap instruction. The resulting
1075 speedup can be by two orders of magnitude or more, although the
1076 tradeoff is that some program locations on some target architectures
1077 might not allow fast tracepoint installation, for instance if the
1078 instruction to be replaced is shorter than the jump. To request a
1079 fast tracepoint, use the "ftrace" command, with syntax identical to
1080 the regular trace command.
1082 ** Disconnected tracing
1084 It is now possible to detach GDB from the target while it is running
1085 a trace experiment, then reconnect later to see how the experiment
1086 is going. In addition, a new variable disconnected-tracing lets you
1087 tell the target agent whether to continue running a trace if the
1088 connection is lost unexpectedly.
1092 GDB now has the ability to save the trace buffer into a file, and
1093 then use that file as a target, similarly to you can do with
1094 corefiles. You can select trace frames, print data that was
1095 collected in them, and use tstatus to display the state of the
1096 tracing run at the moment that it was saved. To create a trace
1097 file, use "tsave <filename>", and to use it, do "target tfile
1100 ** Circular trace buffer
1102 You can ask the target agent to handle the trace buffer as a
1103 circular buffer, discarding the oldest trace frames to make room for
1104 newer ones, by setting circular-trace-buffer to on. This feature may
1105 not be available for all target agents.
1110 The disassemble command, when invoked with two arguments, now requires
1111 the arguments to be comma-separated.
1114 The info variables command now displays variable definitions. Files
1115 which only declare a variable are not shown.
1118 The source command is now capable of sourcing Python scripts.
1119 This feature is dependent on the debugger being build with Python
1122 Related to this enhancement is also the introduction of a new command
1123 "set script-extension" (see below).
1125 * New commands (for set/show, see "New options" below)
1127 record save [<FILENAME>]
1128 Save a file (in core file format) containing the process record
1129 execution log for replay debugging at a later time.
1131 record restore <FILENAME>
1132 Restore the process record execution log that was saved at an
1133 earlier time, for replay debugging.
1135 add-inferior [-copies <N>] [-exec <FILENAME>]
1138 clone-inferior [-copies <N>] [ID]
1139 Make a new inferior ready to execute the same program another
1140 inferior has loaded.
1145 maint info program-spaces
1146 List the program spaces loaded into GDB.
1148 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1149 show remote interrupt-sequence
1150 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1151 as the sequence to the remote target in order to interrupt the execution.
1152 Ctrl-C is a default. Some system prefers BREAK which is high level of
1153 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1154 Magic SysRq g. It is BREAK signal and character 'g'.
1156 set remote interrupt-on-connect [on | off]
1157 show remote interrupt-on-connect
1158 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1159 remote target when gdb connects to it. This is needed when you debug
1162 set remotebreak [on | off]
1164 Deprecated. Use "set/show remote interrupt-sequence" instead.
1166 tvariable $NAME [ = EXP ]
1167 Create or modify a trace state variable.
1170 List trace state variables and their values.
1172 delete tvariable $NAME ...
1173 Delete one or more trace state variables.
1176 Evaluate the given expressions without collecting anything into the
1177 trace buffer. (Valid in tracepoint actions only.)
1179 ftrace FN / FILE:LINE / *ADDR
1180 Define a fast tracepoint at the given function, line, or address.
1182 * New expression syntax
1184 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1185 GDB now parses 0b101010 identically with 42.
1189 set follow-exec-mode new|same
1190 show follow-exec-mode
1191 Control whether GDB reuses the same inferior across an exec call or
1192 creates a new one. This is useful to be able to restart the old
1193 executable after the inferior having done an exec call.
1195 set default-collect EXPR, ...
1196 show default-collect
1197 Define a list of expressions to be collected at each tracepoint.
1198 This is a useful way to ensure essential items are not overlooked,
1199 such as registers or a critical global variable.
1201 set disconnected-tracing
1202 show disconnected-tracing
1203 If set to 1, the target is instructed to continue tracing if it
1204 loses its connection to GDB. If 0, the target is to stop tracing
1207 set circular-trace-buffer
1208 show circular-trace-buffer
1209 If set to on, the target is instructed to use a circular trace buffer
1210 and discard the oldest trace frames instead of stopping the trace due
1211 to a full trace buffer. If set to off, the trace stops when the buffer
1212 fills up. Some targets may not support this.
1214 set script-extension off|soft|strict
1215 show script-extension
1216 If set to "off", the debugger does not perform any script language
1217 recognition, and all sourced files are assumed to be GDB scripts.
1218 If set to "soft" (the default), files are sourced according to
1219 filename extension, falling back to GDB scripts if the first
1221 If set to "strict", files are sourced according to filename extension.
1223 set ada trust-PAD-over-XVS on|off
1224 show ada trust-PAD-over-XVS
1225 If off, activate a workaround against a bug in the debugging information
1226 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1227 the GCC sources for more information about the GNAT encoding and
1228 PAD types in particular). It is always safe to set this option to
1229 off, but this introduces a slight performance penalty. The default
1232 * Python API Improvements
1234 ** GDB provides the new class gdb.LazyString. This is useful in
1235 some pretty-printing cases. The new method gdb.Value.lazy_string
1236 provides a simple way to create objects of this type.
1238 ** The fields returned by gdb.Type.fields now have an
1239 `is_base_class' attribute.
1241 ** The new method gdb.Type.range returns the range of an array type.
1243 ** The new method gdb.parse_and_eval can be used to parse and
1244 evaluate an expression.
1246 * New remote packets
1249 Define a trace state variable.
1252 Get the current value of a trace state variable.
1255 Set desired tracing behavior upon disconnection.
1258 Set the trace buffer to be linear or circular.
1261 Get data about the tracepoints currently in use.
1265 Process record now works correctly with hardware watchpoints.
1267 Multiple bug fixes have been made to the mips-irix port, making it
1268 much more reliable. In particular:
1269 - Debugging threaded applications is now possible again. Previously,
1270 GDB would hang while starting the program, or while waiting for
1271 the program to stop at a breakpoint.
1272 - Attaching to a running process no longer hangs.
1273 - An error occurring while loading a core file has been fixed.
1274 - Changing the value of the PC register now works again. This fixes
1275 problems observed when using the "jump" command, or when calling
1276 a function from GDB, or even when assigning a new value to $pc.
1277 - With the "finish" and "return" commands, the return value for functions
1278 returning a small array is now correctly printed.
1279 - It is now possible to break on shared library code which gets executed
1280 during a shared library init phase (code executed while executing
1281 their .init section). Previously, the breakpoint would have no effect.
1282 - GDB is now able to backtrace through the signal handler for
1283 non-threaded programs.
1285 PIE (Position Independent Executable) programs debugging is now supported.
1286 This includes debugging execution of PIC (Position Independent Code) shared
1287 libraries although for that, it should be possible to run such libraries as an
1290 *** Changes in GDB 7.0
1292 * GDB now has an interface for JIT compilation. Applications that
1293 dynamically generate code can create symbol files in memory and register
1294 them with GDB. For users, the feature should work transparently, and
1295 for JIT developers, the interface is documented in the GDB manual in the
1296 "JIT Compilation Interface" chapter.
1298 * Tracepoints may now be conditional. The syntax is as for
1299 breakpoints; either an "if" clause appended to the "trace" command,
1300 or the "condition" command is available. GDB sends the condition to
1301 the target for evaluation using the same bytecode format as is used
1302 for tracepoint actions.
1304 * The disassemble command now supports: an optional /r modifier, print the
1305 raw instructions in hex as well as in symbolic form, and an optional /m
1306 modifier to print mixed source+assembly.
1308 * Process record and replay
1310 In a architecture environment that supports ``process record and
1311 replay'', ``process record and replay'' target can record a log of
1312 the process execution, and replay it with both forward and reverse
1315 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1316 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1317 set execution-direction {forward|reverse}, for targets that support
1320 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1321 feature is available with a native GDB running on kernel version
1324 * GDB now has support for multi-byte and wide character sets on the
1325 target. Strings whose character type is wchar_t, char16_t, or
1326 char32_t are now correctly printed. GDB supports wide- and unicode-
1327 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1328 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1329 `printf'. This feature requires iconv to work properly; if your
1330 system does not have a working iconv, GDB can use GNU libiconv. See
1331 the installation instructions for more information.
1333 * GDB now supports automatic retrieval of shared library files from
1334 remote targets. To use this feature, specify a system root that begins
1335 with the `remote:' prefix, either via the `set sysroot' command or via
1336 the `--with-sysroot' configure-time option.
1338 * "info sharedlibrary" now takes an optional regex of libraries to show,
1339 and it now reports if a shared library has no debugging information.
1341 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1342 now complete on file names.
1344 * When completing in expressions, gdb will attempt to limit
1345 completions to allowable structure or union fields, where appropriate.
1346 For instance, consider:
1348 # struct example { int f1; double f2; };
1349 # struct example variable;
1352 If the user types TAB at the end of this command line, the available
1353 completions will be "f1" and "f2".
1355 * Inlined functions are now supported. They show up in backtraces, and
1356 the "step", "next", and "finish" commands handle them automatically.
1358 * GDB now supports the token-splicing (##) and stringification (#)
1359 operators when expanding macros. It also supports variable-arity
1362 * GDB now supports inspecting extra signal information, exported by
1363 the new $_siginfo convenience variable. The feature is currently
1364 implemented on linux ARM, i386 and amd64.
1366 * GDB can now display the VFP floating point registers and NEON vector
1367 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1368 can provide these registers (requires Linux 2.6.30 or later). Remote
1369 and simulator targets may also provide them.
1371 * New remote packets
1374 Search memory for a sequence of bytes.
1377 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1378 operation over reliable transport links. Use of this packet is
1379 controlled by the `set remote noack-packet' command.
1382 Kill the process with the specified process ID. Use this in preference
1383 to `k' when multiprocess protocol extensions are supported.
1386 Obtains additional operating system information
1390 Read or write additional signal information.
1392 * Removed remote protocol undocumented extension
1394 An undocumented extension to the remote protocol's `S' stop reply
1395 packet that permited the stub to pass a process id was removed.
1396 Remote servers should use the `T' stop reply packet instead.
1398 * GDB now supports multiple function calling conventions according to the
1399 DWARF-2 DW_AT_calling_convention function attribute.
1401 * The SH target utilizes the aforementioned change to distinguish between gcc
1402 and Renesas calling convention. It also adds the new CLI commands
1403 `set/show sh calling-convention'.
1405 * GDB can now read compressed debug sections, as produced by GNU gold
1406 with the --compress-debug-sections=zlib flag.
1408 * 64-bit core files are now supported on AIX.
1410 * Thread switching is now supported on Tru64.
1412 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1413 which will be allocated using malloc later in program execution.
1415 * The qXfer:libraries:read remote procotol packet now allows passing a
1416 list of section offsets.
1418 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1419 conditions handling signals delivered during attach or thread creation
1420 have also been fixed.
1422 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1423 From the user's standpoint, all unqualified instances of True and False
1424 are treated as the standard definitions, regardless of context.
1426 * GDB now parses C++ symbol and type names more flexibly. For
1429 template<typename T> class C { };
1432 GDB will now correctly handle all of:
1434 ptype C<char const *>
1435 ptype C<char const*>
1436 ptype C<const char *>
1437 ptype C<const char*>
1439 * New features in the GDB remote stub, gdbserver
1441 - The "--wrapper" command-line argument tells gdbserver to use a
1442 wrapper program to launch programs for debugging.
1444 - On PowerPC and S/390 targets, it is now possible to use a single
1445 gdbserver executable to debug both 32-bit and 64-bit programs.
1446 (This requires gdbserver itself to be built as a 64-bit executable.)
1448 - gdbserver uses the new noack protocol mode for TCP connections to
1449 reduce communications latency, if also supported and enabled in GDB.
1451 - Support for the sparc64-linux-gnu target is now included in
1454 - The amd64-linux build of gdbserver now supports debugging both
1455 32-bit and 64-bit programs.
1457 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1458 now support hardware watchpoints, and will use them automatically
1463 GDB now has support for scripting using Python. Whether this is
1464 available is determined at configure time.
1466 New GDB commands can now be written in Python.
1468 * Ada tasking support
1470 Ada tasks can now be inspected in GDB. The following commands have
1474 Print the list of Ada tasks.
1476 Print detailed information about task number N.
1478 Print the task number of the current task.
1480 Switch the context of debugging to task number N.
1482 * Support for user-defined prefixed commands. The "define" command can
1483 add new commands to existing prefixes, e.g. "target".
1485 * Multi-inferior, multi-process debugging.
1487 GDB now has generalized support for multi-inferior debugging. See
1488 "Debugging Multiple Inferiors" in the manual for more information.
1489 Although availability still depends on target support, the command
1490 set is more uniform now. The GNU/Linux specific multi-forks support
1491 has been migrated to this new framework. This implied some user
1492 visible changes; see "New commands" and also "Removed commands"
1495 * Target descriptions can now describe the target OS ABI. See the
1496 "Target Description Format" section in the user manual for more
1499 * Target descriptions can now describe "compatible" architectures
1500 to indicate that the target can execute applications for a different
1501 architecture in addition to those for the main target architecture.
1502 See the "Target Description Format" section in the user manual for
1505 * Multi-architecture debugging.
1507 GDB now includes general supports for debugging applications on
1508 hybrid systems that use more than one single processor architecture
1509 at the same time. Each such hybrid architecture still requires
1510 specific support to be added. The only hybrid architecture supported
1511 in this version of GDB is the Cell Broadband Engine.
1513 * GDB now supports integrated debugging of Cell/B.E. applications that
1514 use both the PPU and SPU architectures. To enable support for hybrid
1515 Cell/B.E. debugging, you need to configure GDB to support both the
1516 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1517 --enable-targets configure option.
1519 * Non-stop mode debugging.
1521 For some targets, GDB now supports an optional mode of operation in
1522 which you can examine stopped threads while other threads continue
1523 to execute freely. This is referred to as non-stop mode, with the
1524 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1525 section in the user manual for more information.
1527 To be able to support remote non-stop debugging, a remote stub needs
1528 to implement the non-stop mode remote protocol extensions, as
1529 described in the "Remote Non-Stop" section of the user manual. The
1530 GDB remote stub, gdbserver, has been adjusted to support these
1531 extensions on linux targets.
1533 * New commands (for set/show, see "New options" below)
1535 catch syscall [NAME(S) | NUMBER(S)]
1536 Catch system calls. Arguments, which should be names of system
1537 calls or their numbers, mean catch only those syscalls. Without
1538 arguments, every syscall will be caught. When the inferior issues
1539 any of the specified syscalls, GDB will stop and announce the system
1540 call, both when it is called and when its call returns. This
1541 feature is currently available with a native GDB running on the
1542 Linux Kernel, under the following architectures: x86, x86_64,
1543 PowerPC and PowerPC64.
1545 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1547 Search memory for a sequence of bytes.
1549 maint set python print-stack
1550 maint show python print-stack
1551 Show a stack trace when an error is encountered in a Python script.
1554 Invoke CODE by passing it to the Python interpreter.
1559 These allow macros to be defined, undefined, and listed
1563 Show operating system information about processes.
1566 List the inferiors currently under GDB's control.
1569 Switch focus to inferior number NUM.
1572 Detach from inferior number NUM.
1575 Kill inferior number NUM.
1579 set spu stop-on-load
1580 show spu stop-on-load
1581 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1583 set spu auto-flush-cache
1584 show spu auto-flush-cache
1585 Control whether to automatically flush the software-managed cache
1586 during Cell/B.E. debugging.
1588 set sh calling-convention
1589 show sh calling-convention
1590 Control the calling convention used when calling SH target functions.
1593 show debug timestamp
1594 Control display of timestamps with GDB debugging output.
1596 set disassemble-next-line
1597 show disassemble-next-line
1598 Control display of disassembled source lines or instructions when
1601 set remote noack-packet
1602 show remote noack-packet
1603 Set/show the use of remote protocol QStartNoAckMode packet. See above
1604 under "New remote packets."
1606 set remote query-attached-packet
1607 show remote query-attached-packet
1608 Control use of remote protocol `qAttached' (query-attached) packet.
1610 set remote read-siginfo-object
1611 show remote read-siginfo-object
1612 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1615 set remote write-siginfo-object
1616 show remote write-siginfo-object
1617 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1620 set remote reverse-continue
1621 show remote reverse-continue
1622 Control use of remote protocol 'bc' (reverse-continue) packet.
1624 set remote reverse-step
1625 show remote reverse-step
1626 Control use of remote protocol 'bs' (reverse-step) packet.
1628 set displaced-stepping
1629 show displaced-stepping
1630 Control displaced stepping mode. Displaced stepping is a way to
1631 single-step over breakpoints without removing them from the debuggee.
1632 Also known as "out-of-line single-stepping".
1635 show debug displaced
1636 Control display of debugging info for displaced stepping.
1638 maint set internal-error
1639 maint show internal-error
1640 Control what GDB does when an internal error is detected.
1642 maint set internal-warning
1643 maint show internal-warning
1644 Control what GDB does when an internal warning is detected.
1649 Use a wrapper program to launch programs for debugging.
1651 set multiple-symbols (all|ask|cancel)
1652 show multiple-symbols
1653 The value of this variable can be changed to adjust the debugger behavior
1654 when an expression or a breakpoint location contains an ambiguous symbol
1655 name (an overloaded function name, for instance).
1657 set breakpoint always-inserted
1658 show breakpoint always-inserted
1659 Keep breakpoints always inserted in the target, as opposed to inserting
1660 them when resuming the target, and removing them when the target stops.
1661 This option can improve debugger performance on slow remote targets.
1663 set arm fallback-mode (arm|thumb|auto)
1664 show arm fallback-mode
1665 set arm force-mode (arm|thumb|auto)
1667 These commands control how ARM GDB determines whether instructions
1668 are ARM or Thumb. The default for both settings is auto, which uses
1669 the current CPSR value for instructions without symbols; previous
1670 versions of GDB behaved as if "set arm fallback-mode arm".
1672 set disable-randomization
1673 show disable-randomization
1674 Standalone programs run with the virtual address space randomization enabled
1675 by default on some platforms. This option keeps the addresses stable across
1676 multiple debugging sessions.
1680 Control whether other threads are stopped or not when some thread hits
1685 Requests that asynchronous execution is enabled in the target, if available.
1686 In this case, it's possible to resume target in the background, and interact
1687 with GDB while the target is running. "show target-async" displays the
1688 current state of asynchronous execution of the target.
1690 set target-wide-charset
1691 show target-wide-charset
1692 The target-wide-charset is the name of the character set that GDB
1693 uses when printing characters whose type is wchar_t.
1695 set tcp auto-retry (on|off)
1697 set tcp connect-timeout
1698 show tcp connect-timeout
1699 These commands allow GDB to retry failed TCP connections to a remote stub
1700 with a specified timeout period; this is useful if the stub is launched
1701 in parallel with GDB but may not be ready to accept connections immediately.
1703 set libthread-db-search-path
1704 show libthread-db-search-path
1705 Control list of directories which GDB will search for appropriate
1708 set schedule-multiple (on|off)
1709 show schedule-multiple
1710 Allow GDB to resume all threads of all processes or only threads of
1711 the current process.
1715 Use more aggressive caching for accesses to the stack. This improves
1716 performance of remote debugging (particularly backtraces) without
1717 affecting correctness.
1719 set interactive-mode (on|off|auto)
1720 show interactive-mode
1721 Control whether GDB runs in interactive mode (on) or not (off).
1722 When in interactive mode, GDB waits for the user to answer all
1723 queries. Otherwise, GDB does not wait and assumes the default
1724 answer. When set to auto (the default), GDB determines which
1725 mode to use based on the stdin settings.
1730 For program forks, this is replaced by the new more generic `info
1731 inferiors' command. To list checkpoints, you can still use the
1732 `info checkpoints' command, which was an alias for the `info forks'
1736 Replaced by the new `inferior' command. To switch between
1737 checkpoints, you can still use the `restart' command, which was an
1738 alias for the `fork' command.
1741 This is removed, since some targets don't have a notion of
1742 processes. To switch between processes, you can still use the
1743 `inferior' command using GDB's own inferior number.
1746 For program forks, this is replaced by the new more generic `kill
1747 inferior' command. To delete a checkpoint, you can still use the
1748 `delete checkpoint' command, which was an alias for the `delete
1752 For program forks, this is replaced by the new more generic `detach
1753 inferior' command. To detach a checkpoint, you can still use the
1754 `detach checkpoint' command, which was an alias for the `detach
1757 * New native configurations
1759 x86/x86_64 Darwin i[34567]86-*-darwin*
1761 x86_64 MinGW x86_64-*-mingw*
1765 Lattice Mico32 lm32-*
1766 x86 DICOS i[34567]86-*-dicos*
1767 x86_64 DICOS x86_64-*-dicos*
1770 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1771 (mingw32ce) debugging.
1777 These commands were actually not implemented on any target.
1779 *** Changes in GDB 6.8
1781 * New native configurations
1783 NetBSD/hppa hppa*-*netbsd*
1784 Xtensa GNU/Linux xtensa*-*-linux*
1788 NetBSD/hppa hppa*-*-netbsd*
1789 Xtensa GNU/Lunux xtensa*-*-linux*
1791 * Change in command line behavior -- corefiles vs. process ids.
1793 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1794 attaching to process NUMBER fails, GDB no longer attempts to open a
1795 core file named NUMBER. Attaching to a program using the -c option
1796 is no longer supported. Instead, use the '-p' or '--pid' options.
1798 * GDB can now be built as a native debugger for debugging Windows x86
1799 (mingw32) Portable Executable (PE) programs.
1801 * Pending breakpoints no longer change their number when their address
1804 * GDB now supports breakpoints with multiple locations,
1805 including breakpoints on C++ constructors, inside C++ templates,
1806 and in inlined functions.
1808 * GDB's ability to debug optimized code has been improved. GDB more
1809 accurately identifies function bodies and lexical blocks that occupy
1810 more than one contiguous range of addresses.
1812 * Target descriptions can now describe registers for PowerPC.
1814 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1815 registers on PowerPC targets.
1817 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1818 targets even when the libthread_db library is not available.
1820 * The GDB remote stub, gdbserver, now supports the new file transfer
1821 commands (remote put, remote get, and remote delete).
1823 * The GDB remote stub, gdbserver, now supports run and attach in
1824 extended-remote mode.
1826 * hppa*64*-*-hpux11* target broken
1827 The debugger is unable to start a program and fails with the following
1828 error: "Error trying to get information about dynamic linker".
1829 The gdb-6.7 release is also affected.
1831 * GDB now supports the --enable-targets= configure option to allow
1832 building a single GDB executable that supports multiple remote
1833 target architectures.
1835 * GDB now supports debugging C and C++ programs which use the
1836 Decimal Floating Point extension. In addition, the PowerPC target
1837 now has a set of pseudo-registers to inspect decimal float values
1838 stored in two consecutive float registers.
1840 * The -break-insert MI command can optionally create pending
1843 * Improved support for debugging Ada
1844 Many improvements to the Ada language support have been made. These
1846 - Better support for Ada2005 interface types
1847 - Improved handling of arrays and slices in general
1848 - Better support for Taft-amendment types
1849 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1851 - Improved command completion in Ada
1854 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1859 set print frame-arguments (all|scalars|none)
1860 show print frame-arguments
1861 The value of this variable can be changed to control which argument
1862 values should be printed by the debugger when displaying a frame.
1867 Transfer files to and from a remote target, and delete remote files.
1874 Transfer files to and from a remote target, and delete remote files.
1876 * New remote packets
1883 Open, close, read, write, and delete files on the remote system.
1886 Attach to an existing process on the remote system, in extended-remote
1890 Run a new process on the remote system, in extended-remote mode.
1892 *** Changes in GDB 6.7
1894 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1895 bfd, libiberty and opcodes, as revealed by static analysis donated by
1896 Coverity, Inc. (http://scan.coverity.com).
1898 * When looking up multiply-defined global symbols, GDB will now prefer the
1899 symbol definition in the current shared library if it was built using the
1900 -Bsymbolic linker option.
1902 * When the Text User Interface (TUI) is not configured, GDB will now
1903 recognize the -tui command-line option and print a message that the TUI
1906 * The GDB remote stub, gdbserver, now has lower overhead for high
1907 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1909 * GDB for MIPS targets now autodetects whether a remote target provides
1910 32-bit or 64-bit register values.
1912 * Support for C++ member pointers has been improved.
1914 * GDB now understands XML target descriptions, which specify the
1915 target's overall architecture. GDB can read a description from
1916 a local file or over the remote serial protocol.
1918 * Vectors of single-byte data use a new integer type which is not
1919 automatically displayed as character or string data.
1921 * The /s format now works with the print command. It displays
1922 arrays of single-byte integers and pointers to single-byte integers
1925 * Target descriptions can now describe target-specific registers,
1926 for architectures which have implemented the support (currently
1927 only ARM, M68K, and MIPS).
1929 * GDB and the GDB remote stub, gdbserver, now support the XScale
1932 * The GDB remote stub, gdbserver, has been updated to support
1933 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1934 has been rewritten to use the standard GDB remote protocol.
1936 * GDB can now step into C++ functions which are called through thunks.
1938 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1940 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1941 layout. It also supports a TextSeg= and DataSeg= response when only
1942 segment base addresses (rather than offsets) are available.
1944 * The /i format now outputs any trailing branch delay slot instructions
1945 immediately following the last instruction within the count specified.
1947 * The GDB remote protocol "T" stop reply packet now supports a
1948 "library" response. Combined with the new "qXfer:libraries:read"
1949 packet, this response allows GDB to debug shared libraries on targets
1950 where the operating system manages the list of loaded libraries (e.g.
1951 Windows and SymbianOS).
1953 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1954 (DLLs) on Windows and Windows CE targets.
1956 * GDB now supports a faster verification that a .debug file matches its binary
1957 according to its build-id signature, if the signature is present.
1963 Enable or disable hardware flow control (RTS/CTS) on the serial port
1964 when debugging using remote targets.
1966 set mem inaccessible-by-default
1967 show mem inaccessible-by-default
1968 If the target supplies a memory map, for instance via the remote
1969 protocol's "qXfer:memory-map:read" packet, setting this variable
1970 prevents GDB from accessing memory outside the memory map. This
1971 is useful for targets with memory mapped registers or which react
1972 badly to accesses of unmapped address space.
1974 set breakpoint auto-hw
1975 show breakpoint auto-hw
1976 If the target supplies a memory map, for instance via the remote
1977 protocol's "qXfer:memory-map:read" packet, setting this variable
1978 lets GDB use hardware breakpoints automatically for memory regions
1979 where it can not use software breakpoints. This covers both the
1980 "break" command and internal breakpoints used for other commands
1981 including "next" and "finish".
1984 catch exception unhandled
1985 Stop the program execution when Ada exceptions are raised.
1988 Stop the program execution when an Ada assertion failed.
1992 Set an alternate system root for target files. This is a more
1993 general version of "set solib-absolute-prefix", which is now
1994 an alias to "set sysroot".
1997 Provide extended SPU facility status information. This set of
1998 commands is available only when debugging the Cell/B.E. SPU
2001 * New native configurations
2003 OpenBSD/sh sh*-*openbsd*
2006 unset tdesc filename
2008 Use the specified local file as an XML target description, and do
2009 not query the target for its built-in description.
2013 OpenBSD/sh sh*-*-openbsd*
2014 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2015 Toshiba Media Processor mep-elf
2017 * New remote packets
2020 Ignore the specified signals; pass them directly to the debugged program
2021 without stopping other threads or reporting them to GDB.
2023 qXfer:features:read:
2024 Read an XML target description from the target, which describes its
2029 Read or write contents of an spufs file on the target system. These
2030 packets are available only on the Cell/B.E. SPU architecture.
2032 qXfer:libraries:read:
2033 Report the loaded shared libraries. Combined with new "T" packet
2034 response, this packet allows GDB to debug shared libraries on
2035 targets where the operating system manages the list of loaded
2036 libraries (e.g. Windows and SymbianOS).
2040 Support for these obsolete configurations has been removed.
2048 i[34567]86-*-lynxos*
2049 i[34567]86-*-netware*
2050 i[34567]86-*-sco3.2v5*
2051 i[34567]86-*-sco3.2v4*
2053 i[34567]86-*-sysv4.2*
2056 i[34567]86-*-unixware2*
2057 i[34567]86-*-unixware*
2066 * Other removed features
2073 Various m68k-only ROM monitors.
2080 Various Renesas ROM monitors and debugging interfaces for SH and
2085 Support for a Macraigor serial interface to on-chip debugging.
2086 GDB does not directly support the newer parallel or USB
2091 A debug information format. The predecessor to DWARF 2 and
2092 DWARF 3, which are still supported.
2094 Support for the HP aCC compiler on HP-UX/PA-RISC
2096 SOM-encapsulated symbolic debugging information, automatic
2097 invocation of pxdb, and the aCC custom C++ ABI. This does not
2098 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2099 with aCC can still be debugged on an assembly level.
2101 MIPS ".pdr" sections
2103 A MIPS-specific format used to describe stack frame layout
2104 in debugging information.
2108 GDB could work with an older version of Guile to debug
2109 the interpreter and Scheme programs running in it.
2111 set mips stack-arg-size
2112 set mips saved-gpreg-size
2114 Use "set mips abi" to control parameter passing for MIPS.
2116 *** Changes in GDB 6.6
2121 Cell Broadband Engine SPU spu-elf
2123 * GDB can now be configured as a cross-debugger targeting native Windows
2124 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2125 running on a Windows system over TCP/IP to debug Windows programs.
2127 * The GDB remote stub, gdbserver, has been updated to support Windows and
2128 Cygwin debugging. Both single-threaded and multi-threaded programs are
2131 * The "set trust-readonly-sections" command works again. This command was
2132 broken in GDB 6.3, 6.4, and 6.5.
2134 * The "load" command now supports writing to flash memory, if the remote
2135 stub provides the required support.
2137 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2138 longer requires symbolic debug information (e.g. DWARF-2).
2143 unset substitute-path
2144 show substitute-path
2145 Manage a list of substitution rules that GDB uses to rewrite the name
2146 of the directories where the sources are located. This can be useful
2147 for instance when the sources were moved to a different location
2148 between compilation and debugging.
2152 Print each CLI command as it is executed. Each command is prefixed with
2153 a number of `+' symbols representing the nesting depth.
2154 The source command now has a `-v' option to enable the same feature.
2158 The ARM Demon monitor support (RDP protocol, "target rdp").
2160 Kernel Object Display, an embedded debugging feature which only worked with
2161 an obsolete version of Cisco IOS.
2163 The 'set download-write-size' and 'show download-write-size' commands.
2165 * New remote packets
2168 Tell a stub about GDB client features, and request remote target features.
2169 The first feature implemented is PacketSize, which allows the target to
2170 specify the size of packets it can handle - to minimize the number of
2171 packets required and improve performance when connected to a remote
2175 Fetch an OS auxilliary vector from the remote stub. This packet is a
2176 more efficient replacement for qPart:auxv:read.
2178 qXfer:memory-map:read:
2179 Fetch a memory map from the remote stub, including information about
2180 RAM, ROM, and flash memory devices.
2185 Erase and program a flash memory device.
2187 * Removed remote packets
2190 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2191 used it, and only gdbserver implemented it.
2193 *** Changes in GDB 6.5
2197 Renesas M32C/M16C m32c-elf
2199 Morpho Technologies ms1 ms1-elf
2203 init-if-undefined Initialize a convenience variable, but
2204 only if it doesn't already have a value.
2206 The following commands are presently only implemented for native GNU/Linux:
2208 checkpoint Save a snapshot of the program state.
2210 restart <n> Return the program state to a
2211 previously saved state.
2213 info checkpoints List currently saved checkpoints.
2215 delete-checkpoint <n> Delete a previously saved checkpoint.
2217 set|show detach-on-fork Tell gdb whether to detach from a newly
2218 forked process, or to keep debugging it.
2220 info forks List forks of the user program that
2221 are available to be debugged.
2223 fork <n> Switch to debugging one of several
2224 forks of the user program that are
2225 available to be debugged.
2227 delete-fork <n> Delete a fork from the list of forks
2228 that are available to be debugged (and
2229 kill the forked process).
2231 detach-fork <n> Delete a fork from the list of forks
2232 that are available to be debugged (and
2233 allow the process to continue).
2237 Morpho Technologies ms2 ms1-elf
2239 * Improved Windows host support
2241 GDB now builds as a cross debugger hosted on i686-mingw32, including
2242 native console support, and remote communications using either
2243 network sockets or serial ports.
2245 * Improved Modula-2 language support
2247 GDB can now print most types in the Modula-2 syntax. This includes:
2248 basic types, set types, record types, enumerated types, range types,
2249 pointer types and ARRAY types. Procedure var parameters are correctly
2250 printed and hexadecimal addresses and character constants are also
2251 written in the Modula-2 syntax. Best results can be obtained by using
2252 GNU Modula-2 together with the -gdwarf-2 command line option.
2256 The ARM rdi-share module.
2258 The Netware NLM debug server.
2260 *** Changes in GDB 6.4
2262 * New native configurations
2264 OpenBSD/arm arm*-*-openbsd*
2265 OpenBSD/mips64 mips64-*-openbsd*
2269 Morpho Technologies ms1 ms1-elf
2271 * New command line options
2273 --batch-silent As for --batch, but totally silent.
2274 --return-child-result The debugger will exist with the same value
2275 the child (debugged) program exited with.
2276 --eval-command COMMAND, -ex COMMAND
2277 Execute a single GDB CLI command. This may be
2278 specified multiple times and in conjunction
2279 with the --command (-x) option.
2281 * Deprecated commands removed
2283 The following commands, that were deprecated in 2000, have been
2287 set|show arm disassembly-flavor set|show arm disassembler
2288 othernames set arm disassembler
2289 set|show remotedebug set|show debug remote
2290 set|show archdebug set|show debug arch
2291 set|show eventdebug set|show debug event
2294 * New BSD user-level threads support
2296 It is now possible to debug programs using the user-level threads
2297 library on OpenBSD and FreeBSD. Currently supported (target)
2300 FreeBSD/amd64 x86_64-*-freebsd*
2301 FreeBSD/i386 i386-*-freebsd*
2302 OpenBSD/i386 i386-*-openbsd*
2304 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2305 are not yet supported.
2307 * New support for Matsushita MN10300 w/sim added
2308 (Work in progress). mn10300-elf.
2310 * REMOVED configurations and files
2312 VxWorks and the XDR protocol *-*-vxworks
2313 Motorola MCORE mcore-*-*
2314 National Semiconductor NS32000 ns32k-*-*
2316 * New "set print array-indexes" command
2318 After turning this setting "on", GDB prints the index of each element
2319 when displaying arrays. The default is "off" to preserve the previous
2322 * VAX floating point support
2324 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2326 * User-defined command support
2328 In addition to using $arg0..$arg9 for argument passing, it is now possible
2329 to use $argc to determine now many arguments have been passed. See the
2330 section on user-defined commands in the user manual for more information.
2332 *** Changes in GDB 6.3:
2334 * New command line option
2336 GDB now accepts -l followed by a number to set the timeout for remote
2339 * GDB works with GCC -feliminate-dwarf2-dups
2341 GDB now supports a more compact representation of DWARF-2 debug
2342 information using DW_FORM_ref_addr references. These are produced
2343 by GCC with the option -feliminate-dwarf2-dups and also by some
2344 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2345 to use -feliminate-dwarf2-dups.
2347 * Internationalization
2349 When supported by the host system, GDB will be built with
2350 internationalization (libintl). The task of marking up the sources is
2351 continued, we're looking forward to our first translation.
2355 Initial support for debugging programs compiled with the GNAT
2356 implementation of the Ada programming language has been integrated
2357 into GDB. In this release, support is limited to expression evaluation.
2359 * New native configurations
2361 GNU/Linux/m32r m32r-*-linux-gnu
2365 GDB's remote protocol now includes support for the 'p' packet. This
2366 packet is used to fetch individual registers from a remote inferior.
2368 * END-OF-LIFE registers[] compatibility module
2370 GDB's internal register infrastructure has been completely rewritten.
2371 The new infrastructure making possible the implementation of key new
2372 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2375 GDB 6.3 will be the last release to include the the registers[]
2376 compatibility module that allowed out-of-date configurations to
2377 continue to work. This change directly impacts the following
2387 powerpc bdm protocol
2389 Unless there is activity to revive these configurations, they will be
2390 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2392 * OBSOLETE configurations and files
2394 Configurations that have been declared obsolete in this release have
2395 been commented out. Unless there is activity to revive these
2396 configurations, the next release of GDB will have their sources
2397 permanently REMOVED.
2406 *** Changes in GDB 6.2.1:
2408 * MIPS `break main; run' gave an heuristic-fence-post warning
2410 When attempting to run even a simple program, a warning about
2411 heuristic-fence-post being hit would be reported. This problem has
2414 * MIPS IRIX 'long double' crashed GDB
2416 When examining a long double variable, GDB would get a segmentation
2417 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2418 IRIX long double values).
2422 A bug in the VAX stack code was causing problems with the "next"
2423 command. This problem has been fixed.
2425 *** Changes in GDB 6.2:
2427 * Fix for ``many threads''
2429 On GNU/Linux systems that use the NPTL threads library, a program
2430 rapidly creating and deleting threads would confuse GDB leading to the
2433 ptrace: No such process.
2434 thread_db_get_info: cannot get thread info: generic error
2436 This problem has been fixed.
2438 * "-async" and "-noasync" options removed.
2440 Support for the broken "-noasync" option has been removed (it caused
2443 * New ``start'' command.
2445 This command runs the program until the begining of the main procedure.
2447 * New BSD Kernel Data Access Library (libkvm) interface
2449 Using ``target kvm'' it is now possible to debug kernel core dumps and
2450 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2451 platforms. Currently supported (native-only) configurations are:
2453 FreeBSD/amd64 x86_64-*-freebsd*
2454 FreeBSD/i386 i?86-*-freebsd*
2455 NetBSD/i386 i?86-*-netbsd*
2456 NetBSD/m68k m68*-*-netbsd*
2457 NetBSD/sparc sparc-*-netbsd*
2458 OpenBSD/amd64 x86_64-*-openbsd*
2459 OpenBSD/i386 i?86-*-openbsd*
2460 OpenBSD/m68k m68*-openbsd*
2461 OpenBSD/sparc sparc-*-openbsd*
2463 * Signal trampoline code overhauled
2465 Many generic problems with GDB's signal handling code have been fixed.
2466 These include: backtraces through non-contiguous stacks; recognition
2467 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2468 call; backtrace through a signal trampoline; step into and out of
2469 signal handlers; and single-stepping in the signal trampoline.
2471 Please note that kernel bugs are a limiting factor here. These
2472 features have been shown to work on an s390 GNU/Linux system that
2473 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2475 * Cygwin support for DWARF 2 added.
2477 * New native configurations
2479 GNU/Linux/hppa hppa*-*-linux*
2480 OpenBSD/hppa hppa*-*-openbsd*
2481 OpenBSD/m68k m68*-*-openbsd*
2482 OpenBSD/m88k m88*-*-openbsd*
2483 OpenBSD/powerpc powerpc-*-openbsd*
2484 NetBSD/vax vax-*-netbsd*
2485 OpenBSD/vax vax-*-openbsd*
2487 * END-OF-LIFE frame compatibility module
2489 GDB's internal frame infrastructure has been completely rewritten.
2490 The new infrastructure making it possible to support key new features
2491 including DWARF 2 Call Frame Information. To aid in the task of
2492 migrating old configurations to this new infrastructure, a
2493 compatibility module, that allowed old configurations to continue to
2494 work, was also included.
2496 GDB 6.2 will be the last release to include this frame compatibility
2497 module. This change directly impacts the following configurations:
2507 Unless there is activity to revive these configurations, they will be
2508 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2510 * REMOVED configurations and files
2512 Sun 3, running SunOS 3 m68*-*-sunos3*
2513 Sun 3, running SunOS 4 m68*-*-sunos4*
2514 Sun 2, running SunOS 3 m68000-*-sunos3*
2515 Sun 2, running SunOS 4 m68000-*-sunos4*
2516 Motorola 680x0 running LynxOS m68*-*-lynxos*
2517 AT&T 3b1/Unix pc m68*-att-*
2518 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2519 decstation mips-dec-* mips-little-*
2520 riscos mips-*-riscos* mips-*-sysv*
2521 sonymips mips-sony-*
2522 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2524 *** Changes in GDB 6.1.1:
2526 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2528 The TUI (Text-mode User Interface) is now built as part of a default
2529 GDB configuration. It is enabled by either selecting the TUI with the
2530 command line option "-i=tui" or by running the separate "gdbtui"
2531 program. For more information on the TUI, see the manual "Debugging
2534 * Pending breakpoint support (also included in GDB 6.1)
2536 Support has been added to allow you to specify breakpoints in shared
2537 libraries that have not yet been loaded. If a breakpoint location
2538 cannot be found, and the "breakpoint pending" option is set to auto,
2539 GDB queries you if you wish to make the breakpoint pending on a future
2540 shared-library load. If and when GDB resolves the breakpoint symbol,
2541 the pending breakpoint is removed as one or more regular breakpoints
2544 Pending breakpoints are very useful for GCJ Java debugging.
2546 * Fixed ISO-C build problems
2548 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2549 non ISO-C code that stopped them being built using a more strict ISO-C
2550 compiler (e.g., IBM's C compiler).
2552 * Fixed build problem on IRIX 5
2554 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2555 wasn't able to compile compile on an IRIX 5 system.
2557 * Added execute permission to gdb/gdbserver/configure
2559 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2560 permission. This bug would cause configure to fail on a number of
2561 systems (Solaris, IRIX). Ref: server/519.
2563 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2565 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2566 has been updated to use constant array sizes.
2568 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2570 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2571 its generated DWARF Call Frame Info. This encoding was causing GDB to
2572 panic, that panic has been fixed. Ref: gdb/1628.
2574 * Fixed a problem when examining parameters in shared library code.
2576 When examining parameters in optimized shared library code generated
2577 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2578 not available''. GDB now correctly displays the variable's value.
2580 *** Changes in GDB 6.1:
2582 * Removed --with-mmalloc
2584 Support for the mmalloc memory manager has been removed, as it
2585 conflicted with the internal gdb byte cache.
2587 * Changes in AMD64 configurations
2589 The AMD64 target now includes the %cs and %ss registers. As a result
2590 the AMD64 remote protocol has changed; this affects the floating-point
2591 and SSE registers. If you rely on those registers for your debugging,
2592 you should upgrade gdbserver on the remote side.
2594 * Revised SPARC target
2596 The SPARC target has been completely revised, incorporating the
2597 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2598 support for LynxOS and SunOS 4 has been dropped. Calling functions
2599 from within GDB on operating systems with a non-executable stack
2600 (Solaris, OpenBSD) now works.
2604 GDB has a new C++ demangler which does a better job on the mangled
2605 names generated by current versions of g++. It also runs faster, so
2606 with this and other changes gdb should now start faster on large C++
2609 * DWARF 2 Location Expressions
2611 GDB support for location expressions has been extended to support function
2612 arguments and frame bases. Older versions of GDB could crash when they
2615 * C++ nested types and namespaces
2617 GDB's support for nested types and namespaces in C++ has been
2618 improved, especially if you use the DWARF 2 debugging format. (This
2619 is the default for recent versions of GCC on most platforms.)
2620 Specifically, if you have a class "Inner" defined within a class or
2621 namespace "Outer", then GDB realizes that the class's name is
2622 "Outer::Inner", not simply "Inner". This should greatly reduce the
2623 frequency of complaints about not finding RTTI symbols. In addition,
2624 if you are stopped at inside of a function defined within a namespace,
2625 GDB modifies its name lookup accordingly.
2627 * New native configurations
2629 NetBSD/amd64 x86_64-*-netbsd*
2630 OpenBSD/amd64 x86_64-*-openbsd*
2631 OpenBSD/alpha alpha*-*-openbsd*
2632 OpenBSD/sparc sparc-*-openbsd*
2633 OpenBSD/sparc64 sparc64-*-openbsd*
2635 * New debugging protocols
2637 M32R with SDI protocol m32r-*-elf*
2639 * "set prompt-escape-char" command deleted.
2641 The command "set prompt-escape-char" has been deleted. This command,
2642 and its very obscure effet on GDB's prompt, was never documented,
2643 tested, nor mentioned in the NEWS file.
2645 * OBSOLETE configurations and files
2647 Configurations that have been declared obsolete in this release have
2648 been commented out. Unless there is activity to revive these
2649 configurations, the next release of GDB will have their sources
2650 permanently REMOVED.
2652 Sun 3, running SunOS 3 m68*-*-sunos3*
2653 Sun 3, running SunOS 4 m68*-*-sunos4*
2654 Sun 2, running SunOS 3 m68000-*-sunos3*
2655 Sun 2, running SunOS 4 m68000-*-sunos4*
2656 Motorola 680x0 running LynxOS m68*-*-lynxos*
2657 AT&T 3b1/Unix pc m68*-att-*
2658 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2659 decstation mips-dec-* mips-little-*
2660 riscos mips-*-riscos* mips-*-sysv*
2661 sonymips mips-sony-*
2662 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2664 * REMOVED configurations and files
2666 SGI Irix-4.x mips-sgi-irix4 or iris4
2667 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2668 Z8000 simulator z8k-zilog-none or z8ksim
2669 Matsushita MN10200 w/simulator mn10200-*-*
2670 H8/500 simulator h8500-hitachi-hms or h8500hms
2671 HP/PA running BSD hppa*-*-bsd*
2672 HP/PA running OSF/1 hppa*-*-osf*
2673 HP/PA Pro target hppa*-*-pro*
2674 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2675 386BSD i[3456]86-*-bsd*
2676 Sequent family i[3456]86-sequent-sysv4*
2677 i[3456]86-sequent-sysv*
2678 i[3456]86-sequent-bsd*
2679 SPARC running LynxOS sparc-*-lynxos*
2680 SPARC running SunOS 4 sparc-*-sunos4*
2681 Tsqware Sparclet sparclet-*-*
2682 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2684 *** Changes in GDB 6.0:
2688 Support for debugging the Objective-C programming language has been
2689 integrated into GDB.
2691 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2693 DWARF 2's Call Frame Information makes available compiler generated
2694 information that more exactly describes the program's run-time stack.
2695 By using this information, GDB is able to provide more robust stack
2698 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2699 have been updated to use a new backtrace mechanism which includes
2700 DWARF 2 CFI support.
2704 GDB's remote protocol has been extended to include support for hosted
2705 file I/O (where the remote target uses GDB's file system). See GDB's
2706 remote protocol documentation for details.
2708 * All targets using the new architecture framework.
2710 All of GDB's targets have been updated to use the new internal
2711 architecture framework. The way is now open for future GDB releases
2712 to include cross-architecture native debugging support (i386 on amd64,
2715 * GNU/Linux's Thread Local Storage (TLS)
2717 GDB now includes support for for the GNU/Linux implementation of
2718 per-thread variables.
2720 * GNU/Linux's Native POSIX Thread Library (NPTL)
2722 GDB's thread code has been updated to work with either the new
2723 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2725 * Separate debug info.
2727 GDB, in conjunction with BINUTILS, now supports a mechanism for
2728 automatically loading debug information from a separate file. Instead
2729 of shipping full debug and non-debug versions of system libraries,
2730 system integrators can now instead ship just the stripped libraries
2731 and optional debug files.
2733 * DWARF 2 Location Expressions
2735 DWARF 2 Location Expressions allow the compiler to more completely
2736 describe the location of variables (even in optimized code) to the
2739 GDB now includes preliminary support for location expressions (support
2740 for DW_OP_piece is still missing).
2744 A number of long standing bugs that caused GDB to die while starting a
2745 Java application have been fixed. GDB's Java support is now
2746 considered "useable".
2748 * GNU/Linux support for fork, vfork, and exec.
2750 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2751 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2754 * GDB supports logging output to a file
2756 There are two new commands, "set logging" and "show logging", which can be
2757 used to capture GDB's output to a file.
2759 * The meaning of "detach" has changed for gdbserver
2761 The "detach" command will now resume the application, as documented. To
2762 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2765 * d10v, m68hc11 `regs' command deprecated
2767 The `info registers' command has been updated so that it displays the
2768 registers using a format identical to the old `regs' command.
2772 A new command, "maint set profile on/off", has been added. This command can
2773 be used to enable or disable profiling while running GDB, to profile a
2774 session or a set of commands. In addition there is a new configure switch,
2775 "--enable-profiling", which will cause GDB to be compiled with profiling
2776 data, for more informative profiling results.
2778 * Default MI syntax changed to "mi2".
2780 The default MI (machine interface) syntax, enabled by the command line
2781 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2782 "mi1", can be enabled by specifying the option "-i=mi1".
2784 Support for the original "mi0" syntax (included in GDB 5.0) has been
2787 Fix for gdb/192: removed extraneous space when displaying frame level.
2788 Fix for gdb/672: update changelist is now output in mi list format.
2789 Fix for gdb/702: a -var-assign that updates the value now shows up
2790 in a subsequent -var-update.
2792 * New native configurations.
2794 FreeBSD/amd64 x86_64-*-freebsd*
2796 * Multi-arched targets.
2798 HP/PA HPUX11 hppa*-*-hpux*
2799 Renesas M32R/D w/simulator m32r-*-elf*
2801 * OBSOLETE configurations and files
2803 Configurations that have been declared obsolete in this release have
2804 been commented out. Unless there is activity to revive these
2805 configurations, the next release of GDB will have their sources
2806 permanently REMOVED.
2808 Z8000 simulator z8k-zilog-none or z8ksim
2809 Matsushita MN10200 w/simulator mn10200-*-*
2810 H8/500 simulator h8500-hitachi-hms or h8500hms
2811 HP/PA running BSD hppa*-*-bsd*
2812 HP/PA running OSF/1 hppa*-*-osf*
2813 HP/PA Pro target hppa*-*-pro*
2814 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2815 Sequent family i[3456]86-sequent-sysv4*
2816 i[3456]86-sequent-sysv*
2817 i[3456]86-sequent-bsd*
2818 Tsqware Sparclet sparclet-*-*
2819 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2821 * REMOVED configurations and files
2824 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2825 IBM AIX PS/2 i[3456]86-*-aix
2826 i386 running Mach 3.0 i[3456]86-*-mach3*
2827 i386 running Mach i[3456]86-*-mach*
2828 i386 running OSF/1 i[3456]86-*osf1mk*
2829 HP/Apollo 68k Family m68*-apollo*-sysv*,
2831 m68*-hp-bsd*, m68*-hp-hpux*
2832 Argonaut Risc Chip (ARC) arc-*-*
2833 Mitsubishi D30V d30v-*-*
2834 Fujitsu FR30 fr30-*-elf*
2835 OS/9000 i[34]86-*-os9k
2836 I960 with MON960 i960-*-coff
2838 * MIPS $fp behavior changed
2840 The convenience variable $fp, for the MIPS, now consistently returns
2841 the address of the current frame's base. Previously, depending on the
2842 context, $fp could refer to either $sp or the current frame's base
2843 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2844 The GNU Source-Level Debugger''.
2846 *** Changes in GDB 5.3:
2848 * GNU/Linux shared library multi-threaded performance improved.
2850 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2851 `/proc', in preference to `ptrace' for memory reads. This may result
2852 in an improvement in the start-up time of multi-threaded, shared
2853 library applications when run under GDB. One GDB user writes: ``loads
2854 shared libs like mad''.
2856 * ``gdbserver'' now supports multi-threaded applications on some targets
2858 Support for debugging multi-threaded applications which use
2859 the GNU/Linux LinuxThreads package has been added for
2860 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2861 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2863 * GDB now supports C/C++ preprocessor macros.
2865 GDB now expands preprocessor macro invocations in C/C++ expressions,
2866 and provides various commands for showing macro definitions and how
2869 The new command `macro expand EXPRESSION' expands any macro
2870 invocations in expression, and shows the result.
2872 The new command `show macro MACRO-NAME' shows the definition of the
2873 macro named MACRO-NAME, and where it was defined.
2875 Most compilers don't include information about macros in the debugging
2876 information by default. In GCC 3.1, for example, you need to compile
2877 your program with the options `-gdwarf-2 -g3'. If the macro
2878 information is present in the executable, GDB will read it.
2880 * Multi-arched targets.
2882 DEC Alpha (partial) alpha*-*-*
2883 DEC VAX (partial) vax-*-*
2885 National Semiconductor NS32000 (partial) ns32k-*-*
2886 Motorola 68000 (partial) m68k-*-*
2887 Motorola MCORE mcore-*-*
2891 Fujitsu FRV architecture added by Red Hat frv*-*-*
2894 * New native configurations
2896 Alpha NetBSD alpha*-*-netbsd*
2897 SH NetBSD sh*-*-netbsdelf*
2898 MIPS NetBSD mips*-*-netbsd*
2899 UltraSPARC NetBSD sparc64-*-netbsd*
2901 * OBSOLETE configurations and files
2903 Configurations that have been declared obsolete in this release have
2904 been commented out. Unless there is activity to revive these
2905 configurations, the next release of GDB will have their sources
2906 permanently REMOVED.
2908 Mitsubishi D30V d30v-*-*
2909 OS/9000 i[34]86-*-os9k
2910 IBM AIX PS/2 i[3456]86-*-aix
2911 Fujitsu FR30 fr30-*-elf*
2912 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2913 Argonaut Risc Chip (ARC) arc-*-*
2914 i386 running Mach 3.0 i[3456]86-*-mach3*
2915 i386 running Mach i[3456]86-*-mach*
2916 i386 running OSF/1 i[3456]86-*osf1mk*
2917 HP/Apollo 68k Family m68*-apollo*-sysv*,
2919 m68*-hp-bsd*, m68*-hp-hpux*
2920 I960 with MON960 i960-*-coff
2922 * OBSOLETE languages
2924 CHILL, a Pascal like language used by telecommunications companies.
2926 * REMOVED configurations and files
2928 AMD 29k family via UDI a29k-amd-udi, udi29k
2929 A29K VxWorks a29k-*-vxworks
2930 AMD 29000 embedded, using EBMON a29k-none-none
2931 AMD 29000 embedded with COFF a29k-none-coff
2932 AMD 29000 embedded with a.out a29k-none-aout
2934 testsuite/gdb.hp/gdb.threads-hp/ directory
2936 * New command "set max-user-call-depth <nnn>"
2938 This command allows the user to limit the call depth of user-defined
2939 commands. The default is 1024.
2941 * Changes in FreeBSD/i386 native debugging.
2943 Support for the "generate-core-file" has been added.
2945 * New commands "dump", "append", and "restore".
2947 These commands allow data to be copied from target memory
2948 to a bfd-format or binary file (dump and append), and back
2949 from a file into memory (restore).
2951 * Improved "next/step" support on multi-processor Alpha Tru64.
2953 The previous single-step mechanism could cause unpredictable problems,
2954 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2955 of a software single-step mechanism prevents this.
2957 *** Changes in GDB 5.2.1:
2965 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2966 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2967 Fix, by Joel Brobecker imported from mainline.
2969 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2970 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2971 Fix, by Fred Fish, imported from mainline.
2973 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2974 Surprisingly enough, it works now.
2975 By Michal Ludvig, imported from mainline.
2977 i386 hardware watchpoint support:
2978 avoid misses on second run for some targets.
2979 By Pierre Muller, imported from mainline.
2981 *** Changes in GDB 5.2:
2983 * New command "set trust-readonly-sections on[off]".
2985 This command is a hint that tells gdb that read-only sections
2986 really are read-only (ie. that their contents will not change).
2987 In this mode, gdb will go to the object file rather than the
2988 target to read memory from read-only sections (such as ".text").
2989 This can be a significant performance improvement on some
2990 (notably embedded) targets.
2992 * New command "generate-core-file" (or "gcore").
2994 This new gdb command allows the user to drop a core file of the child
2995 process state at any time. So far it's been implemented only for
2996 GNU/Linux and Solaris, but should be relatively easily ported to other
2997 hosts. Argument is core file name (defaults to core.<pid>).
2999 * New command line option
3001 GDB now accepts --pid or -p followed by a process id.
3003 * Change in command line behavior -- corefiles vs. process ids.
3005 There is a subtle behavior in the way in which GDB handles
3006 command line arguments. The first non-flag argument is always
3007 a program to debug, but the second non-flag argument may either
3008 be a corefile or a process id. Previously, GDB would attempt to
3009 open the second argument as a corefile, and if that failed, would
3010 issue a superfluous error message and then attempt to attach it as
3011 a process. Now, if the second argument begins with a non-digit,
3012 it will be treated as a corefile. If it begins with a digit,
3013 GDB will attempt to attach it as a process, and if no such process
3014 is found, will then attempt to open it as a corefile.
3016 * Changes in ARM configurations.
3018 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3019 configuration is fully multi-arch.
3021 * New native configurations
3023 ARM NetBSD arm*-*-netbsd*
3024 x86 OpenBSD i[3456]86-*-openbsd*
3025 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3026 Sparc64 running FreeBSD sparc64-*-freebsd*
3030 Sanyo XStormy16 xstormy16-elf
3032 * OBSOLETE configurations and files
3034 Configurations that have been declared obsolete in this release have
3035 been commented out. Unless there is activity to revive these
3036 configurations, the next release of GDB will have their sources
3037 permanently REMOVED.
3039 AMD 29k family via UDI a29k-amd-udi, udi29k
3040 A29K VxWorks a29k-*-vxworks
3041 AMD 29000 embedded, using EBMON a29k-none-none
3042 AMD 29000 embedded with COFF a29k-none-coff
3043 AMD 29000 embedded with a.out a29k-none-aout
3045 testsuite/gdb.hp/gdb.threads-hp/ directory
3047 * REMOVED configurations and files
3049 TI TMS320C80 tic80-*-*
3051 PowerPC Solaris powerpcle-*-solaris*
3052 PowerPC Windows NT powerpcle-*-cygwin32
3053 PowerPC Netware powerpc-*-netware*
3054 Harris/CXUX m88k m88*-harris-cxux*
3055 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3056 ns32k-utek-sysv* ns32k-utek-*
3057 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3058 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3059 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3060 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3061 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3063 * Changes to command line processing
3065 The new `--args' feature can be used to specify command-line arguments
3066 for the inferior from gdb's command line.
3068 * Changes to key bindings
3070 There is a new `operate-and-get-next' function bound to `C-o'.
3072 *** Changes in GDB 5.1.1
3074 Fix compile problem on DJGPP.
3076 Fix a problem with floating-point registers on the i386 being
3079 Fix to stop GDB crashing on .debug_str debug info.
3081 Numerous documentation fixes.
3083 Numerous testsuite fixes.
3085 *** Changes in GDB 5.1:
3087 * New native configurations
3089 Alpha FreeBSD alpha*-*-freebsd*
3090 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3091 MIPS GNU/Linux mips*-*-linux*
3092 MIPS SGI Irix 6.x mips*-sgi-irix6*
3093 ia64 AIX ia64-*-aix*
3094 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3098 Motorola 68HC11 and 68HC12 m68hc11-elf
3100 UltraSparc running GNU/Linux sparc64-*-linux*
3102 * OBSOLETE configurations and files
3104 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3105 Harris/CXUX m88k m88*-harris-cxux*
3106 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3107 ns32k-utek-sysv* ns32k-utek-*
3108 TI TMS320C80 tic80-*-*
3110 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3111 PowerPC Solaris powerpcle-*-solaris*
3112 PowerPC Windows NT powerpcle-*-cygwin32
3113 PowerPC Netware powerpc-*-netware*
3114 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3115 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3116 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3117 Apple Macintosh (MPW) host N/A
3119 stuff.c (Program to stuff files into a specially prepared space in kdb)
3120 kdb-start.c (Main loop for the standalone kernel debugger)
3122 Configurations that have been declared obsolete in this release have
3123 been commented out. Unless there is activity to revive these
3124 configurations, the next release of GDB will have their sources
3125 permanently REMOVED.
3127 * REMOVED configurations and files
3129 Altos 3068 m68*-altos-*
3130 Convex c1-*-*, c2-*-*
3132 ARM RISCix arm-*-* (as host)
3136 * GDB has been converted to ISO C.
3138 GDB's source code has been converted to ISO C. In particular, the
3139 sources are fully protoized, and rely on standard headers being
3144 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3146 * The MI enabled by default.
3148 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3149 revised and enabled by default. Packages which use GDB as a debugging
3150 engine behind a UI or another front end are encouraged to switch to
3151 using the GDB/MI interface, instead of the old annotations interface
3152 which is now deprecated.
3154 * Support for debugging Pascal programs.
3156 GDB now includes support for debugging Pascal programs. The following
3157 main features are supported:
3159 - Pascal-specific data types such as sets;
3161 - automatic recognition of Pascal sources based on file-name
3164 - Pascal-style display of data types, variables, and functions;
3166 - a Pascal expression parser.
3168 However, some important features are not yet supported.
3170 - Pascal string operations are not supported at all;
3172 - there are some problems with boolean types;
3174 - Pascal type hexadecimal constants are not supported
3175 because they conflict with the internal variables format;
3177 - support for Pascal objects and classes is not full yet;
3179 - unlike Pascal, GDB is case-sensitive for symbol names.
3181 * Changes in completion.
3183 Commands such as `shell', `run' and `set args', which pass arguments
3184 to inferior programs, now complete on file names, similar to what
3185 users expect at the shell prompt.
3187 Commands which accept locations, such as `disassemble', `print',
3188 `breakpoint', `until', etc. now complete on filenames as well as
3189 program symbols. Thus, if you type "break foob TAB", and the source
3190 files linked into the programs include `foobar.c', that file name will
3191 be one of the candidates for completion. However, file names are not
3192 considered for completion after you typed a colon that delimits a file
3193 name from a name of a function in that file, as in "break foo.c:bar".
3195 `set demangle-style' completes on available demangling styles.
3197 * New platform-independent commands:
3199 It is now possible to define a post-hook for a command as well as a
3200 hook that runs before the command. For more details, see the
3201 documentation of `hookpost' in the GDB manual.
3203 * Changes in GNU/Linux native debugging.
3205 Support for debugging multi-threaded programs has been completely
3206 revised for all platforms except m68k and sparc. You can now debug as
3207 many threads as your system allows you to have.
3209 Attach/detach is supported for multi-threaded programs.
3211 Support for SSE registers was added for x86. This doesn't work for
3212 multi-threaded programs though.
3214 * Changes in MIPS configurations.
3216 Multi-arch support is enabled for all MIPS configurations.
3218 GDB can now be built as native debugger on SGI Irix 6.x systems for
3219 debugging n32 executables. (Debugging 64-bit executables is not yet
3222 * Unified support for hardware watchpoints in all x86 configurations.
3224 Most (if not all) native x86 configurations support hardware-assisted
3225 breakpoints and watchpoints in a unified manner. This support
3226 implements debug register sharing between watchpoints, which allows to
3227 put a virtually infinite number of watchpoints on the same address,
3228 and also supports watching regions up to 16 bytes with several debug
3231 The new maintenance command `maintenance show-debug-regs' toggles
3232 debugging print-outs in functions that insert, remove, and test
3233 watchpoints and hardware breakpoints.
3235 * Changes in the DJGPP native configuration.
3237 New command ``info dos sysinfo'' displays assorted information about
3238 the CPU, OS, memory, and DPMI server.
3240 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3241 display information about segment descriptors stored in GDT, LDT, and
3244 New commands ``info dos pde'' and ``info dos pte'' display entries
3245 from Page Directory and Page Tables (for now works with CWSDPMI only).
3246 New command ``info dos address-pte'' displays the Page Table entry for
3247 a given linear address.
3249 GDB can now pass command lines longer than 126 characters to the
3250 program being debugged (requires an update to the libdbg.a library
3251 which is part of the DJGPP development kit).
3253 DWARF2 debug info is now supported.
3255 It is now possible to `step' and `next' through calls to `longjmp'.
3257 * Changes in documentation.
3259 All GDB documentation was converted to GFDL, the GNU Free
3260 Documentation License.
3262 Tracepoints-related commands are now fully documented in the GDB
3265 TUI, the Text-mode User Interface, is now documented in the manual.
3267 Tracepoints-related commands are now fully documented in the GDB
3270 The "GDB Internals" manual now has an index. It also includes
3271 documentation of `ui_out' functions, GDB coding standards, x86
3272 hardware watchpoints, and memory region attributes.
3274 * GDB's version number moved to ``version.in''
3276 The Makefile variable VERSION has been replaced by the file
3277 ``version.in''. People creating GDB distributions should update the
3278 contents of this file.
3282 GUD support is now a standard part of the EMACS distribution.
3284 *** Changes in GDB 5.0:
3286 * Improved support for debugging FP programs on x86 targets
3288 Unified and much-improved support for debugging floating-point
3289 programs on all x86 targets. In particular, ``info float'' now
3290 displays the FP registers in the same format on all x86 targets, with
3291 greater level of detail.
3293 * Improvements and bugfixes in hardware-assisted watchpoints
3295 It is now possible to watch array elements, struct members, and
3296 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3297 on x86 targets no longer erroneously trigger when the address is
3300 * Improvements in the native DJGPP version of GDB
3302 The distribution now includes all the scripts and auxiliary files
3303 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3304 machines ``out of the box''.
3306 The DJGPP version can now debug programs that use signals. It is
3307 possible to catch signals that happened in the debuggee, deliver
3308 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3309 would kill the program being debugged.) Programs that hook hardware
3310 interrupts (keyboard, timer, etc.) can also be debugged.
3312 It is now possible to debug DJGPP programs that redirect their
3313 standard handles or switch them to raw (as opposed to cooked) mode, or
3314 even close them. The command ``run < foo > bar'' works as expected,
3315 and ``info terminal'' reports useful information about the debuggee's
3316 terminal, including raw/cooked mode, redirection, etc.
3318 The DJGPP version now uses termios functions for console I/O, which
3319 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3322 DOS-style file names with drive letters are now fully supported by
3325 It is now possible to debug DJGPP programs that switch their working
3326 directory. It is also possible to rerun the debuggee any number of
3327 times without restarting GDB; thus, you can use the same setup,
3328 breakpoints, etc. for many debugging sessions.
3330 * New native configurations
3332 ARM GNU/Linux arm*-*-linux*
3333 PowerPC GNU/Linux powerpc-*-linux*
3337 Motorola MCore mcore-*-*
3338 x86 VxWorks i[3456]86-*-vxworks*
3339 PowerPC VxWorks powerpc-*-vxworks*
3340 TI TMS320C80 tic80-*-*
3342 * OBSOLETE configurations
3344 Altos 3068 m68*-altos-*
3345 Convex c1-*-*, c2-*-*
3347 ARM RISCix arm-*-* (as host)
3350 Configurations that have been declared obsolete will be commented out,
3351 but the code will be left in place. If there is no activity to revive
3352 these configurations before the next release of GDB, the sources will
3353 be permanently REMOVED.
3355 * Gould support removed
3357 Support for the Gould PowerNode and NP1 has been removed.
3359 * New features for SVR4
3361 On SVR4 native platforms (such as Solaris), if you attach to a process
3362 without first loading a symbol file, GDB will now attempt to locate and
3363 load symbols from the running process's executable file.
3365 * Many C++ enhancements
3367 C++ support has been greatly improved. Overload resolution now works properly
3368 in almost all cases. RTTI support is on the way.
3370 * Remote targets can connect to a sub-program
3372 A popen(3) style serial-device has been added. This device starts a
3373 sub-process (such as a stand-alone simulator) and then communicates
3374 with that. The sub-program to run is specified using the syntax
3375 ``|<program> <args>'' vis:
3377 (gdb) set remotedebug 1
3378 (gdb) target extended-remote |mn10300-elf-sim program-args
3380 * MIPS 64 remote protocol
3382 A long standing bug in the mips64 remote protocol where by GDB
3383 expected certain 32 bit registers (ex SR) to be transfered as 32
3384 instead of 64 bits has been fixed.
3386 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3387 added to provide backward compatibility with older versions of GDB.
3389 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3391 The command ``set remotebinarydownload'' command has been replaced by
3392 ``set remote X-packet''. Other commands in ``set remote'' family
3393 include ``set remote P-packet''.
3395 * Breakpoint commands accept ranges.
3397 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3398 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3399 ``tracepoint passcount'' also accepts a range of tracepoints.
3401 * ``apropos'' command added.
3403 The ``apropos'' command searches through command names and
3404 documentation strings, printing out matches, making it much easier to
3405 try to find a command that does what you are looking for.
3409 A new machine oriented interface (MI) has been added to GDB. This
3410 interface is designed for debug environments running GDB as a separate
3411 process. This is part of the long term libGDB project. See the
3412 "GDB/MI" chapter of the GDB manual for further information. It can be
3413 enabled by configuring with:
3415 .../configure --enable-gdbmi
3417 *** Changes in GDB-4.18:
3419 * New native configurations
3421 HP-UX 10.20 hppa*-*-hpux10.20
3422 HP-UX 11.x hppa*-*-hpux11.0*
3423 M68K GNU/Linux m68*-*-linux*
3427 Fujitsu FR30 fr30-*-elf*
3428 Intel StrongARM strongarm-*-*
3429 Mitsubishi D30V d30v-*-*
3431 * OBSOLETE configurations
3433 Gould PowerNode, NP1 np1-*-*, pn-*-*
3435 Configurations that have been declared obsolete will be commented out,
3436 but the code will be left in place. If there is no activity to revive
3437 these configurations before the next release of GDB, the sources will
3438 be permanently REMOVED.
3442 As a compatibility experiment, GDB's source files buildsym.h and
3443 buildsym.c have been converted to pure standard C, no longer
3444 containing any K&R compatibility code. We believe that all systems in
3445 use today either come with a standard C compiler, or have a GCC port
3446 available. If this is not true, please report the affected
3447 configuration to bug-gdb@gnu.org immediately. See the README file for
3448 information about getting a standard C compiler if you don't have one
3453 GDB now uses readline 2.2.
3455 * set extension-language
3457 You can now control the mapping between filename extensions and source
3458 languages by using the `set extension-language' command. For instance,
3459 you can ask GDB to treat .c files as C++ by saying
3460 set extension-language .c c++
3461 The command `info extensions' lists all of the recognized extensions
3462 and their associated languages.
3464 * Setting processor type for PowerPC and RS/6000
3466 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3467 you can use the `set processor' command to specify what variant of the
3468 PowerPC family you are debugging. The command
3472 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3473 following PowerPC and RS6000 variants:
3475 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3476 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3478 403GC IBM PowerPC 403GC
3479 505 Motorola PowerPC 505
3480 860 Motorola PowerPC 860 or 850
3481 601 Motorola PowerPC 601
3482 602 Motorola PowerPC 602
3483 603 Motorola/IBM PowerPC 603 or 603e
3484 604 Motorola PowerPC 604 or 604e
3485 750 Motorola/IBM PowerPC 750 or 750
3487 At the moment, this command just tells GDB what to name the
3488 special-purpose processor registers. Since almost all the affected
3489 registers are inaccessible to user-level programs, this command is
3490 only useful for remote debugging in its present form.
3494 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3495 more extensive support for HP-UX. Added features include shared
3496 library support, kernel threads and hardware watchpoints for 11.00,
3497 support for HP's ANSI C and C++ compilers, and a compatibility mode
3498 for xdb and dbx commands.
3502 HP's donation includes the new concept of catchpoints, which is a
3503 generalization of the old catch command. On HP-UX, it is now possible
3504 to catch exec, fork, and vfork, as well as library loading.
3506 This means that the existing catch command has changed; its first
3507 argument now specifies the type of catch to be set up. See the
3508 output of "help catch" for a list of catchpoint types.
3510 * Debugging across forks
3512 On HP-UX, you can choose which process to debug when a fork() happens
3517 HP has donated a curses-based terminal user interface (TUI). To get
3518 it, build with --enable-tui. Although this can be enabled for any
3519 configuration, at present it only works for native HP debugging.
3521 * GDB remote protocol additions
3523 A new protocol packet 'X' that writes binary data is now available.
3524 Default behavior is to try 'X', then drop back to 'M' if the stub
3525 fails to respond. The settable variable `remotebinarydownload'
3526 allows explicit control over the use of 'X'.
3528 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3529 full 64-bit address. The command
3531 set remoteaddresssize 32
3533 can be used to revert to the old behaviour. For existing remote stubs
3534 the change should not be noticed, as the additional address information
3537 In order to assist in debugging stubs, you may use the maintenance
3538 command `packet' to send any text string to the stub. For instance,
3540 maint packet heythere
3542 sends the packet "$heythere#<checksum>". Note that it is very easy to
3543 disrupt a debugging session by sending the wrong packet at the wrong
3546 The compare-sections command allows you to compare section data on the
3547 target to what is in the executable file without uploading or
3548 downloading, by comparing CRC checksums.
3550 * Tracing can collect general expressions
3552 You may now collect general expressions at tracepoints. This requires
3553 further additions to the target-side stub; see tracepoint.c and
3554 doc/agentexpr.texi for further details.
3556 * mask-address variable for Mips
3558 For Mips targets, you may control the zeroing of the upper 32 bits of
3559 a 64-bit address by entering `set mask-address on'. This is mainly
3560 of interest to users of embedded R4xxx and R5xxx processors.
3562 * Higher serial baud rates
3564 GDB's serial code now allows you to specify baud rates 57600, 115200,
3565 230400, and 460800 baud. (Note that your host system may not be able
3566 to achieve all of these rates.)
3570 The i960 configuration now includes an initial implementation of a
3571 builtin simulator, contributed by Jim Wilson.
3574 *** Changes in GDB-4.17:
3576 * New native configurations
3578 Alpha GNU/Linux alpha*-*-linux*
3579 Unixware 2.x i[3456]86-unixware2*
3580 Irix 6.x mips*-sgi-irix6*
3581 PowerPC GNU/Linux powerpc-*-linux*
3582 PowerPC Solaris powerpcle-*-solaris*
3583 Sparc GNU/Linux sparc-*-linux*
3584 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3588 Argonaut Risc Chip (ARC) arc-*-*
3589 Hitachi H8/300S h8300*-*-*
3590 Matsushita MN10200 w/simulator mn10200-*-*
3591 Matsushita MN10300 w/simulator mn10300-*-*
3592 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3593 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3594 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3595 Mitsubishi D10V w/simulator d10v-*-*
3596 Mitsubishi M32R/D w/simulator m32r-*-elf*
3597 Tsqware Sparclet sparclet-*-*
3598 NEC V850 w/simulator v850-*-*
3600 * New debugging protocols
3602 ARM with RDI protocol arm*-*-*
3603 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3604 DDB and LSI variants of PMON protocol mips*-*-*
3605 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3606 PowerPC with SDS protocol powerpc{,le}-*-eabi
3607 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3611 All configurations can now understand and use the DWARF 2 debugging
3612 format. The choice is automatic, if the symbol file contains DWARF 2
3617 GDB now includes basic Java language support. This support is
3618 only useful with Java compilers that produce native machine code.
3620 * solib-absolute-prefix and solib-search-path
3622 For SunOS and SVR4 shared libraries, you may now set the prefix for
3623 loading absolute shared library symbol files, and the search path for
3624 locating non-absolute shared library symbol files.
3626 * Live range splitting
3628 GDB can now effectively debug code for which GCC has performed live
3629 range splitting as part of its optimization. See gdb/doc/LRS for
3630 more details on the expected format of the stabs information.
3634 GDB's support for the GNU Hurd, including thread debugging, has been
3635 updated to work with current versions of the Hurd.
3639 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3640 instruction set. ARM GDB automatically detects when Thumb
3641 instructions are in use, and adjusts disassembly and backtracing
3646 GDB's MIPS target configurations now handle the MIP16 16-bit
3651 GDB now includes support for overlays; if an executable has been
3652 linked such that multiple sections are based at the same address, GDB
3653 will decide which section to use for symbolic info. You can choose to
3654 control the decision manually, using overlay commands, or implement
3655 additional target-side support and use "overlay load-target" to bring
3656 in the overlay mapping. Do "help overlay" for more detail.
3660 The command "info symbol <address>" displays information about
3661 the symbol at the specified address.
3665 The standard remote protocol now includes an extension that allows
3666 asynchronous collection and display of trace data. This requires
3667 extensive support in the target-side debugging stub. Tracing mode
3668 includes a new interaction mode in GDB and new commands: see the
3669 file tracepoint.c for more details.
3673 Configurations for embedded MIPS now include a simulator contributed
3674 by Cygnus Solutions. The simulator supports the instruction sets
3675 of most MIPS variants.
3679 Sparc configurations may now include the ERC32 simulator contributed
3680 by the European Space Agency. The simulator is not built into
3681 Sparc targets by default; configure with --enable-sim to include it.
3685 For target configurations that may include multiple variants of a
3686 basic architecture (such as MIPS and SH), you may now set the
3687 architecture explicitly. "set arch" sets, "info arch" lists
3688 the possible architectures.
3690 *** Changes in GDB-4.16:
3692 * New native configurations
3694 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3695 M68K NetBSD m68k-*-netbsd*
3696 PowerPC AIX 4.x powerpc-*-aix*
3697 PowerPC MacOS powerpc-*-macos*
3698 PowerPC Windows NT powerpcle-*-cygwin32
3699 RS/6000 AIX 4.x rs6000-*-aix4*
3703 ARM with RDP protocol arm-*-*
3704 I960 with MON960 i960-*-coff
3705 MIPS VxWorks mips*-*-vxworks*
3706 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3707 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3709 Matra Sparclet sparclet-*-*
3713 The powerpc-eabi configuration now includes the PSIM simulator,
3714 contributed by Andrew Cagney, with assistance from Mike Meissner.
3715 PSIM is a very elaborate model of the PowerPC, including not only
3716 basic instruction set execution, but also details of execution unit
3717 performance and I/O hardware. See sim/ppc/README for more details.
3721 GDB now works with Solaris 2.5.
3723 * Windows 95/NT native
3725 GDB will now work as a native debugger on Windows 95 and Windows NT.
3726 To build it from source, you must use the "gnu-win32" environment,
3727 which uses a DLL to emulate enough of Unix to run the GNU tools.
3728 Further information, binaries, and sources are available at
3729 ftp.cygnus.com, under pub/gnu-win32.
3731 * dont-repeat command
3733 If a user-defined command includes the command `dont-repeat', then the
3734 command will not be repeated if the user just types return. This is
3735 useful if the command is time-consuming to run, so that accidental
3736 extra keystrokes don't run the same command many times.
3738 * Send break instead of ^C
3740 The standard remote protocol now includes an option to send a break
3741 rather than a ^C to the target in order to interrupt it. By default,
3742 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3744 * Remote protocol timeout
3746 The standard remote protocol includes a new variable `remotetimeout'
3747 that allows you to set the number of seconds before GDB gives up trying
3748 to read from the target. The default value is 2.
3750 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3752 By default GDB will automatically keep track of objects as they are
3753 loaded and unloaded by the dynamic linker. By using the command `set
3754 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3755 when shared library events occur, thus allowing you to set breakpoints
3756 in shared libraries which are explicitly loaded by the inferior.
3758 Note this feature does not work on hpux8. On hpux9 you must link
3759 /usr/lib/end.o into your program. This feature should work
3760 automatically on hpux10.
3762 * Irix 5.x hardware watchpoint support
3764 Irix 5 configurations now support the use of hardware watchpoints.
3766 * Mips protocol "SYN garbage limit"
3768 When debugging a Mips target using the `target mips' protocol, you
3769 may set the number of characters that GDB will ignore by setting
3770 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3771 every character. The default value is 1050.
3773 * Recording and replaying remote debug sessions
3775 If you set `remotelogfile' to the name of a file, gdb will write to it
3776 a recording of a remote debug session. This recording may then be
3777 replayed back to gdb using "gdbreplay". See gdbserver/README for
3778 details. This is useful when you have a problem with GDB while doing
3779 remote debugging; you can make a recording of the session and send it
3780 to someone else, who can then recreate the problem.
3782 * Speedups for remote debugging
3784 GDB includes speedups for downloading and stepping MIPS systems using
3785 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3786 and more efficient S-record downloading.
3788 * Memory use reductions and statistics collection
3790 GDB now uses less memory and reports statistics about memory usage.
3791 Try the `maint print statistics' command, for example.
3793 *** Changes in GDB-4.15:
3795 * Psymtabs for XCOFF
3797 The symbol reader for AIX GDB now uses partial symbol tables. This
3798 can greatly improve startup time, especially for large executables.
3800 * Remote targets use caching
3802 Remote targets now use a data cache to speed up communication with the
3803 remote side. The data cache could lead to incorrect results because
3804 it doesn't know about volatile variables, thus making it impossible to
3805 debug targets which use memory mapped I/O devices. `set remotecache
3806 off' turns the the data cache off.
3808 * Remote targets may have threads
3810 The standard remote protocol now includes support for multiple threads
3811 in the target system, using new protocol commands 'H' and 'T'. See
3812 gdb/remote.c for details.
3816 If GDB is configured with `--enable-netrom', then it will include
3817 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3818 acts as though it is a bank of ROM on the target board, but you can
3819 write into it over the network. GDB's support consists only of
3820 support for fast loading into the emulated ROM; to debug, you must use
3821 another protocol, such as standard remote protocol. The usual
3822 sequence is something like
3824 target nrom <netrom-hostname>
3826 target remote <netrom-hostname>:1235
3830 GDB now includes support for the Apple Macintosh, as a host only. It
3831 may be run as either an MPW tool or as a standalone application, and
3832 it can debug through the serial port. All the usual GDB commands are
3833 available, but to the target command, you must supply "serial" as the
3834 device type instead of "/dev/ttyXX". See mpw-README in the main
3835 directory for more information on how to build. The MPW configuration
3836 scripts */mpw-config.in support only a few targets, and only the
3837 mips-idt-ecoff target has been tested.
3841 GDB configuration now uses autoconf. This is not user-visible,
3842 but does simplify configuration and building.
3846 GDB now supports hpux10.
3848 *** Changes in GDB-4.14:
3850 * New native configurations
3852 x86 FreeBSD i[345]86-*-freebsd
3853 x86 NetBSD i[345]86-*-netbsd
3854 NS32k NetBSD ns32k-*-netbsd
3855 Sparc NetBSD sparc-*-netbsd
3859 A29K VxWorks a29k-*-vxworks
3860 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3861 CPU32 EST-300 emulator m68*-*-est*
3862 PowerPC ELF powerpc-*-elf
3865 * Alpha OSF/1 support for procfs
3867 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3868 possible to attach to running processes. As the mounting of the /proc
3869 filesystem is optional on the Alpha, GDB automatically determines
3870 the availability of /proc during startup. This can lead to problems
3871 if /proc is unmounted after GDB has been started.
3873 * Arguments to user-defined commands
3875 User commands may accept up to 10 arguments separated by whitespace.
3876 Arguments are accessed within the user command via $arg0..$arg9. A
3879 print $arg0 + $arg1 + $arg2
3881 To execute the command use:
3884 Defines the command "adder" which prints the sum of its three arguments.
3885 Note the arguments are text substitutions, so they may reference variables,
3886 use complex expressions, or even perform inferior function calls.
3888 * New `if' and `while' commands
3890 This makes it possible to write more sophisticated user-defined
3891 commands. Both commands take a single argument, which is the
3892 expression to evaluate, and must be followed by the commands to
3893 execute, one per line, if the expression is nonzero, the list being
3894 terminated by the word `end'. The `if' command list may include an
3895 `else' word, which causes the following commands to be executed only
3896 if the expression is zero.
3898 * Fortran source language mode
3900 GDB now includes partial support for Fortran 77. It will recognize
3901 Fortran programs and can evaluate a subset of Fortran expressions, but
3902 variables and functions may not be handled correctly. GDB will work
3903 with G77, but does not yet know much about symbols emitted by other
3906 * Better HPUX support
3908 Most debugging facilities now work on dynamic executables for HPPAs
3909 running hpux9 or later. You can attach to running dynamically linked
3910 processes, but by default the dynamic libraries will be read-only, so
3911 for instance you won't be able to put breakpoints in them. To change
3912 that behavior do the following before running the program:
3918 This will cause the libraries to be mapped private and read-write.
3919 To revert to the normal behavior, do this:
3925 You cannot set breakpoints or examine data in the library until after
3926 the library is loaded if the function/data symbols do not have
3929 GDB can now also read debug symbols produced by the HP C compiler on
3930 HPPAs (sorry, no C++, Fortran or 68k support).
3932 * Target byte order now dynamically selectable
3934 You can choose which byte order to use with a target system, via the
3935 commands "set endian big" and "set endian little", and you can see the
3936 current setting by using "show endian". You can also give the command
3937 "set endian auto", in which case GDB will use the byte order
3938 associated with the executable. Currently, only embedded MIPS
3939 configurations support dynamic selection of target byte order.
3941 * New DOS host serial code
3943 This version uses DPMI interrupts to handle buffered I/O, so you
3944 no longer need to run asynctsr when debugging boards connected to
3947 *** Changes in GDB-4.13:
3949 * New "complete" command
3951 This lists all the possible completions for the rest of the line, if it
3952 were to be given as a command itself. This is intended for use by emacs.
3954 * Trailing space optional in prompt
3956 "set prompt" no longer adds a space for you after the prompt you set. This
3957 allows you to set a prompt which ends in a space or one that does not.
3959 * Breakpoint hit counts
3961 "info break" now displays a count of the number of times the breakpoint
3962 has been hit. This is especially useful in conjunction with "ignore"; you
3963 can ignore a large number of breakpoint hits, look at the breakpoint info
3964 to see how many times the breakpoint was hit, then run again, ignoring one
3965 less than that number, and this will get you quickly to the last hit of
3968 * Ability to stop printing at NULL character
3970 "set print null-stop" will cause GDB to stop printing the characters of
3971 an array when the first NULL is encountered. This is useful when large
3972 arrays actually contain only short strings.
3974 * Shared library breakpoints
3976 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3977 breakpoints in shared libraries before the executable is run.
3979 * Hardware watchpoints
3981 There is a new hardware breakpoint for the watch command for sparclite
3982 targets. See gdb/sparclite/hw_breakpoint.note.
3984 Hardware watchpoints are also now supported under GNU/Linux.
3988 Annotations have been added. These are for use with graphical interfaces,
3989 and are still experimental. Currently only gdba.el uses these.
3991 * Improved Irix 5 support
3993 GDB now works properly with Irix 5.2.
3995 * Improved HPPA support
3997 GDB now works properly with the latest GCC and GAS.
3999 * New native configurations
4001 Sequent PTX4 i[34]86-sequent-ptx4
4002 HPPA running OSF/1 hppa*-*-osf*
4003 Atari TT running SVR4 m68*-*-sysv4*
4004 RS/6000 LynxOS rs6000-*-lynxos*
4008 OS/9000 i[34]86-*-os9k
4009 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4012 * Hitachi SH7000 and E7000-PC ICE support
4014 There is now support for communicating with the Hitachi E7000-PC ICE.
4015 This is available automatically when GDB is configured for the SH.
4019 As usual, a variety of small fixes and improvements, both generic
4020 and configuration-specific. See the ChangeLog for more detail.
4022 *** Changes in GDB-4.12:
4024 * Irix 5 is now supported
4028 GDB-4.12 on the HPPA has a number of changes which make it unable
4029 to debug the output from the currently released versions of GCC and
4030 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4031 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4032 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4035 *** Changes in GDB-4.11:
4037 * User visible changes:
4041 The "set remotedebug" option is now consistent between the mips remote
4042 target, remote targets using the gdb-specific protocol, UDI (AMD's
4043 debug protocol for the 29k) and the 88k bug monitor. It is now an
4044 integer specifying a debug level (normally 0 or 1, but 2 means more
4045 debugging info for the mips target).
4047 * DEC Alpha native support
4049 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4050 debug info, but GDB works fairly well with the DEC compiler and should
4051 work with a future GCC release. See the README file for a few
4052 Alpha-specific notes.
4054 * Preliminary thread implementation
4056 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4058 * LynxOS native and target support for 386
4060 This release has been hosted on LynxOS 2.2, and also can be configured
4061 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4064 * Improvements in C++ mangling/demangling.
4066 This release has much better g++ debugging, specifically in name
4067 mangling/demangling, virtual function calls, print virtual table,
4068 call methods, ...etc.
4070 *** Changes in GDB-4.10:
4072 * User visible changes:
4074 Remote debugging using the GDB-specific (`target remote') protocol now
4075 supports the `load' command. This is only useful if you have some
4076 other way of getting the stub to the target system, and you can put it
4077 somewhere in memory where it won't get clobbered by the download.
4079 Filename completion now works.
4081 When run under emacs mode, the "info line" command now causes the
4082 arrow to point to the line specified. Also, "info line" prints
4083 addresses in symbolic form (as well as hex).
4085 All vxworks based targets now support a user settable option, called
4086 vxworks-timeout. This option represents the number of seconds gdb
4087 should wait for responses to rpc's. You might want to use this if
4088 your vxworks target is, perhaps, a slow software simulator or happens
4089 to be on the far side of a thin network line.
4093 This release contains support for using a DEC alpha as a GDB host for
4094 cross debugging. Native alpha debugging is not supported yet.
4097 *** Changes in GDB-4.9:
4101 This is the first GDB release which is accompanied by a matching testsuite.
4102 The testsuite requires installation of dejagnu, which should be available
4103 via ftp from most sites that carry GNU software.
4107 'Cfront' style demangling has had its name changed to 'ARM' style, to
4108 emphasize that it was written from the specifications in the C++ Annotated
4109 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4110 disclaimers, it still generated too much confusion with users attempting to
4111 use gdb with AT&T cfront.
4115 GDB now uses a standard remote interface to a simulator library.
4116 So far, the library contains simulators for the Zilog Z8001/2, the
4117 Hitachi H8/300, H8/500 and Super-H.
4119 * New targets supported
4121 H8/300 simulator h8300-hitachi-hms or h8300hms
4122 H8/500 simulator h8500-hitachi-hms or h8500hms
4123 SH simulator sh-hitachi-hms or sh
4124 Z8000 simulator z8k-zilog-none or z8ksim
4125 IDT MIPS board over serial line mips-idt-ecoff
4127 Cross-debugging to GO32 targets is supported. It requires a custom
4128 version of the i386-stub.c module which is integrated with the
4129 GO32 memory extender.
4131 * New remote protocols
4133 MIPS remote debugging protocol.
4135 * New source languages supported
4137 This version includes preliminary support for Chill, a Pascal like language
4138 used by telecommunications companies. Chill support is also being integrated
4139 into the GNU compiler, but we don't know when it will be publically available.
4142 *** Changes in GDB-4.8:
4144 * HP Precision Architecture supported
4146 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4147 version of this support was available as a set of patches from the
4148 University of Utah. GDB does not support debugging of programs
4149 compiled with the HP compiler, because HP will not document their file
4150 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4151 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4153 Many problems in the preliminary version have been fixed.
4155 * Faster and better demangling
4157 We have improved template demangling and fixed numerous bugs in the GNU style
4158 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4159 character types (wchar_t) are now supported. Demangling of each symbol is now
4160 only done once, and is cached when the symbol table for a file is read in.
4161 This results in a small increase in memory usage for C programs, a moderate
4162 increase in memory usage for C++ programs, and a fantastic speedup in
4165 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4166 from the specifications in the Annotated Reference Manual, which AT&T's
4167 compiler does not actually implement.
4169 * G++ multiple inheritance compiler problem
4171 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4172 inheritance lattices was reworked to properly discover ambiguities. We
4173 recently found an example which causes this new algorithm to fail in a
4174 very subtle way, producing bad debug information for those classes.
4175 The file 'gcc.patch' (in this directory) can be applied to gcc to
4176 circumvent the problem. A future GCC release will contain a complete
4179 The previous G++ debug info problem (mentioned below for the gdb-4.7
4180 release) is fixed in gcc version 2.3.2.
4182 * Improved configure script
4184 The `configure' script will now attempt to guess your system type if
4185 you don't supply a host system type. The old scheme of supplying a
4186 host system triplet is preferable over using this. All the magic is
4187 done in the new `config.guess' script. Examine it for details.
4189 We have also brought our configure script much more in line with the FSF's
4190 version. It now supports the --with-xxx options. In particular,
4191 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4192 The resulting GDB will not be able to read arbitrary object file formats --
4193 only the format ``expected'' to be used on the configured target system.
4194 We hope to make this the default in a future release.
4196 * Documentation improvements
4198 There's new internal documentation on how to modify GDB, and how to
4199 produce clean changes to the code. We implore people to read it
4200 before submitting changes.
4202 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4203 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4204 `info' files are also provided. To build `info' files from scratch,
4205 you will need the latest `makeinfo' release, which will be available in
4206 a future texinfo-X.Y release.
4208 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4209 We're not sure exactly which versions have this problem, but it has
4210 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4211 or better. If that isn't possible, there is a patch in
4212 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4213 around this problem.
4217 GDB now supports array constants that can be used in expressions typed in by
4218 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4219 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4222 The new directory `gdb/sparclite' contains a program that demonstrates
4223 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4225 * New native hosts supported
4227 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4228 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4230 * New targets supported
4232 AMD 29k family via UDI a29k-amd-udi or udi29k
4234 * New file formats supported
4236 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4237 HPUX core files, and SCO 3.2v2 core files.
4241 Attaching to processes now works again; thanks for the many bug reports.
4243 We have also stomped on a bunch of core dumps caused by
4244 printf_filtered("%s") problems.
4246 We eliminated a copyright problem on the rpc and ptrace header files
4247 for VxWorks, which was discovered at the last minute during the 4.7
4248 release. You should now be able to build a VxWorks GDB.
4250 You can now interrupt gdb while an attached process is running. This
4251 will cause the attached process to stop, and give control back to GDB.
4253 We fixed problems caused by using too many file descriptors
4254 for reading symbols from object files and libraries. This was
4255 especially a problem for programs that used many (~100) shared
4258 The `step' command now only enters a subroutine if there is line number
4259 information for the subroutine. Otherwise it acts like the `next'
4260 command. Previously, `step' would enter subroutines if there was
4261 any debugging information about the routine. This avoids problems
4262 when using `cc -g1' on MIPS machines.
4264 * Internal improvements
4266 GDB's internal interfaces have been improved to make it easier to support
4267 debugging of multiple languages in the future.
4269 GDB now uses a common structure for symbol information internally.
4270 Minimal symbols (derived from linkage symbols in object files), partial
4271 symbols (from a quick scan of debug information), and full symbols
4272 contain a common subset of information, making it easier to write
4273 shared code that handles any of them.
4275 * New command line options
4277 We now accept --silent as an alias for --quiet.
4281 The memory-mapped-malloc library is now licensed under the GNU Library
4282 General Public License.
4284 *** Changes in GDB-4.7:
4286 * Host/native/target split
4288 GDB has had some major internal surgery to untangle the support for
4289 hosts and remote targets. Now, when you configure GDB for a remote
4290 target, it will no longer load in all of the support for debugging
4291 local programs on the host. When fully completed and tested, this will
4292 ensure that arbitrary host/target combinations are possible.
4294 The primary conceptual shift is to separate the non-portable code in
4295 GDB into three categories. Host specific code is required any time GDB
4296 is compiled on that host, regardless of the target. Target specific
4297 code relates to the peculiarities of the target, but can be compiled on
4298 any host. Native specific code is everything else: it can only be
4299 built when the host and target are the same system. Child process
4300 handling and core file support are two common `native' examples.
4302 GDB's use of /proc for controlling Unix child processes is now cleaner.
4303 It has been split out into a single module under the `target_ops' vector,
4304 plus two native-dependent functions for each system that uses /proc.
4306 * New hosts supported
4308 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4309 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4310 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4312 * New targets supported
4314 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4315 68030 and CPU32 m68030-*-*, m68332-*-*
4317 * New native hosts supported
4319 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4320 (386bsd is not well tested yet)
4321 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4323 * New file formats supported
4325 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4326 supports reading of `a.out.adobe' object files, which are an a.out
4327 format extended with minimal information about multiple sections.
4331 `show copying' is the same as the old `info copying'.
4332 `show warranty' is the same as `info warrantee'.
4333 These were renamed for consistency. The old commands continue to work.
4335 `info handle' is a new alias for `info signals'.
4337 You can now define pre-command hooks, which attach arbitrary command
4338 scripts to any command. The commands in the hook will be executed
4339 prior to the user's command. You can also create a hook which will be
4340 executed whenever the program stops. See gdb.texinfo.
4344 We now deal with Cfront style name mangling, and can even extract type
4345 info from mangled symbols. GDB can automatically figure out which
4346 symbol mangling style your C++ compiler uses.
4348 Calling of methods and virtual functions has been improved as well.
4352 The crash that occured when debugging Sun Ansi-C compiled binaries is
4353 fixed. This was due to mishandling of the extra N_SO stabs output
4356 We also finally got Ultrix 4.2 running in house, and fixed core file
4357 support, with help from a dozen people on the net.
4359 John M. Farrell discovered that the reason that single-stepping was so
4360 slow on all of the Mips based platforms (primarily SGI and DEC) was
4361 that we were trying to demangle and lookup a symbol used for internal
4362 purposes on every instruction that was being stepped through. Changing
4363 the name of that symbol so that it couldn't be mistaken for a C++
4364 mangled symbol sped things up a great deal.
4366 Rich Pixley sped up symbol lookups in general by getting much smarter
4367 about when C++ symbol mangling is necessary. This should make symbol
4368 completion (TAB on the command line) much faster. It's not as fast as
4369 we'd like, but it's significantly faster than gdb-4.6.
4373 A new user controllable variable 'call_scratch_address' can
4374 specify the location of a scratch area to be used when GDB
4375 calls a function in the target. This is necessary because the
4376 usual method of putting the scratch area on the stack does not work
4377 in systems that have separate instruction and data spaces.
4379 We integrated changes to support the 29k UDI (Universal Debugger
4380 Interface), but discovered at the last minute that we didn't have all
4381 of the appropriate copyright paperwork. We are working with AMD to
4382 resolve this, and hope to have it available soon.
4386 We have sped up the remote serial line protocol, especially for targets
4387 with lots of registers. It now supports a new `expedited status' ('T')
4388 message which can be used in place of the existing 'S' status message.
4389 This allows the remote stub to send only the registers that GDB
4390 needs to make a quick decision about single-stepping or conditional
4391 breakpoints, eliminating the need to fetch the entire register set for
4392 each instruction being stepped through.
4394 The GDB remote serial protocol now implements a write-through cache for
4395 registers, only re-reading the registers if the target has run.
4397 There is also a new remote serial stub for SPARC processors. You can
4398 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4399 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4400 processor with a serial port.
4404 Configure.in files have become much easier to read and modify. A new
4405 `table driven' format makes it more obvious what configurations are
4406 supported, and what files each one uses.
4410 There is a new opcodes library which will eventually contain all of the
4411 disassembly routines and opcode tables. At present, it only contains
4412 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4413 disassembler (binutils/objdump) to share these routines.
4415 The libiberty library is now copylefted under the GNU Library General
4416 Public License. This allows more liberal use, and was done so libg++
4417 can use it. This makes no difference to GDB, since the Library License
4418 grants all the rights from the General Public License.
4422 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4423 reference to the stabs symbol info used by the debugger. It is (as far
4424 as we know) the only published document on this fascinating topic. We
4425 encourage you to read it, compare it to the stabs information on your
4426 system, and send improvements on the document in general (to
4427 bug-gdb@prep.ai.mit.edu).
4429 And, of course, many bugs have been fixed.
4432 *** Changes in GDB-4.6:
4434 * Better support for C++ function names
4436 GDB now accepts as input the "demangled form" of C++ overloaded function
4437 names and member function names, and can do command completion on such names
4438 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4439 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4440 Make use of command completion, it is your friend.
4442 GDB also now accepts a variety of C++ mangled symbol formats. They are
4443 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4444 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4445 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4446 for the list of formats.
4448 * G++ symbol mangling problem
4450 Recent versions of gcc have a bug in how they emit debugging information for
4451 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4452 directory) can be applied to gcc to fix the problem. Alternatively, if you
4453 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4454 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4455 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4458 * New 'maintenance' command
4460 All of the commands related to hacking GDB internals have been moved out of
4461 the main command set, and now live behind the 'maintenance' command. This
4462 can also be abbreviated as 'mt'. The following changes were made:
4464 dump-me -> maintenance dump-me
4465 info all-breakpoints -> maintenance info breakpoints
4466 printmsyms -> maintenance print msyms
4467 printobjfiles -> maintenance print objfiles
4468 printpsyms -> maintenance print psymbols
4469 printsyms -> maintenance print symbols
4471 The following commands are new:
4473 maintenance demangle Call internal GDB demangler routine to
4474 demangle a C++ link name and prints the result.
4475 maintenance print type Print a type chain for a given symbol
4477 * Change to .gdbinit file processing
4479 We now read the $HOME/.gdbinit file before processing the argv arguments
4480 (e.g. reading symbol files or core files). This allows global parameters to
4481 be set, which will apply during the symbol reading. The ./.gdbinit is still
4482 read after argv processing.
4484 * New hosts supported
4486 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4488 GNU/Linux support i386-unknown-linux or linux
4490 We are also including code to support the HP/PA running BSD and HPUX. This
4491 is almost guaranteed not to work, as we didn't have time to test or build it
4492 for this release. We are including it so that the more adventurous (or
4493 masochistic) of you can play with it. We also had major problems with the
4494 fact that the compiler that we got from HP doesn't support the -g option.
4497 * New targets supported
4499 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4501 * More smarts about finding #include files
4503 GDB now remembers the compilation directory for all include files, and for
4504 all files from which C is generated (like yacc and lex sources). This
4505 greatly improves GDB's ability to find yacc/lex sources, and include files,
4506 especially if you are debugging your program from a directory different from
4507 the one that contains your sources.
4509 We also fixed a bug which caused difficulty with listing and setting
4510 breakpoints in include files which contain C code. (In the past, you had to
4511 try twice in order to list an include file that you hadn't looked at before.)
4513 * Interesting infernals change
4515 GDB now deals with arbitrary numbers of sections, where the symbols for each
4516 section must be relocated relative to that section's landing place in the
4517 target's address space. This work was needed to support ELF with embedded
4518 stabs used by Solaris-2.0.
4520 * Bug fixes (of course!)
4522 There have been loads of fixes for the following things:
4523 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4524 i960, stabs, DOS(GO32), procfs, etc...
4526 See the ChangeLog for details.
4528 *** Changes in GDB-4.5:
4530 * New machines supported (host and target)
4532 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4534 SGI Irix-4.x mips-sgi-irix4 or iris4
4536 * New malloc package
4538 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4539 Mmalloc is capable of handling mutiple heaps of memory. It is also
4540 capable of saving a heap to a file, and then mapping it back in later.
4541 This can be used to greatly speedup the startup of GDB by using a
4542 pre-parsed symbol table which lives in a mmalloc managed heap. For
4543 more details, please read mmalloc/mmalloc.texi.
4547 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4548 'help info proc' for details.
4550 * MIPS ecoff symbol table format
4552 The code that reads MIPS symbol table format is now supported on all hosts.
4553 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4556 * File name changes for MS-DOS
4558 Many files in the config directories have been renamed to make it easier to
4559 support GDB on MS-DOSe systems (which have very restrictive file name
4560 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4561 environment) is close to working but has some remaining problems. Note
4562 that debugging of DOS programs is not supported, due to limitations
4563 in the ``operating system'', but it can be used to host cross-debugging.
4565 * Cross byte order fixes
4567 Many fixes have been made to support cross debugging of Sparc and MIPS
4568 targets from hosts whose byte order differs.
4570 * New -mapped and -readnow options
4572 If memory-mapped files are available on your system through the 'mmap'
4573 system call, you can use the -mapped option on the `file' or
4574 `symbol-file' commands to cause GDB to write the symbols from your
4575 program into a reusable file. If the program you are debugging is
4576 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4577 Future GDB debugging sessions will notice the presence of this file,
4578 and will quickly map in symbol information from it, rather than reading
4579 the symbol table from the executable program. Using the '-mapped'
4580 option in a GDB `file' or `symbol-file' command has the same effect as
4581 starting GDB with the '-mapped' command-line option.
4583 You can cause GDB to read the entire symbol table immediately by using
4584 the '-readnow' option with any of the commands that load symbol table
4585 information (or on the GDB command line). This makes the command
4586 slower, but makes future operations faster.
4588 The -mapped and -readnow options are typically combined in order to
4589 build a `fred.syms' file that contains complete symbol information.
4590 A simple GDB invocation to do nothing but build a `.syms' file for future
4593 gdb -batch -nx -mapped -readnow programname
4595 The `.syms' file is specific to the host machine on which GDB is run.
4596 It holds an exact image of GDB's internal symbol table. It cannot be
4597 shared across multiple host platforms.
4599 * longjmp() handling
4601 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4602 siglongjmp() without losing control. This feature has not yet been ported to
4603 all systems. It currently works on many 386 platforms, all MIPS-based
4604 platforms (SGI, DECstation, etc), and Sun3/4.
4608 Preliminary work has been put in to support the new Solaris OS from Sun. At
4609 this time, it can control and debug processes, but it is not capable of
4614 As always, many many bug fixes. The major areas were with g++, and mipsread.
4615 People using the MIPS-based platforms should experience fewer mysterious
4616 crashes and trashed symbol tables.
4618 *** Changes in GDB-4.4:
4620 * New machines supported (host and target)
4622 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4624 BSD Reno on Vax vax-dec-bsd
4625 Ultrix on Vax vax-dec-ultrix
4627 * New machines supported (target)
4629 AMD 29000 embedded, using EBMON a29k-none-none
4633 GDB continues to improve its handling of C++. `References' work better.
4634 The demangler has also been improved, and now deals with symbols mangled as
4635 per the Annotated C++ Reference Guide.
4637 GDB also now handles `stabs' symbol information embedded in MIPS
4638 `ecoff' symbol tables. Since the ecoff format was not easily
4639 extensible to handle new languages such as C++, this appeared to be a
4640 good way to put C++ debugging info into MIPS binaries. This option
4641 will be supported in the GNU C compiler, version 2, when it is
4644 * New features for SVR4
4646 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4647 shared libraries. Debugging dynamically linked programs should present
4648 only minor differences from debugging statically linked programs.
4650 The `info proc' command will print out information about any process
4651 on an SVR4 system (including the one you are debugging). At the moment,
4652 it prints the address mappings of the process.
4654 If you bring up GDB on another SVR4 system, please send mail to
4655 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4657 * Better dynamic linking support in SunOS
4659 Reading symbols from shared libraries which contain debugging symbols
4660 now works properly. However, there remain issues such as automatic
4661 skipping of `transfer vector' code during function calls, which
4662 make it harder to debug code in a shared library, than to debug the
4663 same code linked statically.
4667 GDB is now using the latest `getopt' routines from the FSF. This
4668 version accepts the -- prefix for options with long names. GDB will
4669 continue to accept the old forms (-option and +option) as well.
4670 Various single letter abbreviations for options have been explicity
4671 added to the option table so that they won't get overshadowed in the
4672 future by other options that begin with the same letter.
4676 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4677 Many assorted bugs have been handled. Many more remain to be handled.
4678 See the various ChangeLog files (primarily in gdb and bfd) for details.
4681 *** Changes in GDB-4.3:
4683 * New machines supported (host and target)
4685 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4686 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4687 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4689 * Almost SCO Unix support
4691 We had hoped to support:
4692 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4693 (except for core file support), but we discovered very late in the release
4694 that it has problems with process groups that render gdb unusable. Sorry
4695 about that. I encourage people to fix it and post the fixes.
4697 * Preliminary ELF and DWARF support
4699 GDB can read ELF object files on System V Release 4, and can handle
4700 debugging records for C, in DWARF format, in ELF files. This support
4701 is preliminary. If you bring up GDB on another SVR4 system, please
4702 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4707 GDB now uses the latest `readline' library. One user-visible change
4708 is that two tabs will list possible command completions, which previously
4709 required typing M-? (meta-question mark, or ESC ?).
4713 The `stepi' bug that many of you noticed has been squashed.
4714 Many bugs in C++ have been handled. Many more remain to be handled.
4715 See the various ChangeLog files (primarily in gdb and bfd) for details.
4717 * State of the MIPS world (in case you wondered):
4719 GDB can understand the symbol tables emitted by the compilers
4720 supplied by most vendors of MIPS-based machines, including DEC. These
4721 symbol tables are in a format that essentially nobody else uses.
4723 Some versions of gcc come with an assembler post-processor called
4724 mips-tfile. This program is required if you want to do source-level
4725 debugging of gcc-compiled programs. I believe FSF does not ship
4726 mips-tfile with gcc version 1, but it will eventually come with gcc
4729 Debugging of g++ output remains a problem. g++ version 1.xx does not
4730 really support it at all. (If you're lucky, you should be able to get
4731 line numbers and stack traces to work, but no parameters or local
4732 variables.) With some work it should be possible to improve the
4735 When gcc version 2 is released, you will have somewhat better luck.
4736 However, even then you will get confusing results for inheritance and
4739 We will eventually provide full debugging of g++ output on
4740 DECstations. This will probably involve some kind of stabs-in-ecoff
4741 encapulation, but the details have not been worked out yet.
4744 *** Changes in GDB-4.2:
4746 * Improved configuration
4748 Only one copy of `configure' exists now, and it is not self-modifying.
4749 Porting BFD is simpler.
4753 The `step' and `next' commands now only stop at the first instruction
4754 of a source line. This prevents the multiple stops that used to occur
4755 in switch statements, for-loops, etc. `Step' continues to stop if a
4756 function that has debugging information is called within the line.
4760 Lots of small bugs fixed. More remain.
4762 * New host supported (not target)
4764 Intel 386 PC clone running Mach i386-none-mach
4767 *** Changes in GDB-4.1:
4769 * Multiple source language support
4771 GDB now has internal scaffolding to handle several source languages.
4772 It determines the type of each source file from its filename extension,
4773 and will switch expression parsing and number formatting to match the
4774 language of the function in the currently selected stack frame.
4775 You can also specifically set the language to be used, with
4776 `set language c' or `set language modula-2'.
4780 GDB now has preliminary support for the GNU Modula-2 compiler,
4781 currently under development at the State University of New York at
4782 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4783 continue through the fall of 1991 and into 1992.
4785 Other Modula-2 compilers are currently not supported, and attempting to
4786 debug programs compiled with them will likely result in an error as the
4787 symbol table is read. Feel free to work on it, though!
4789 There are hooks in GDB for strict type checking and range checking,
4790 in the `Modula-2 philosophy', but they do not currently work.
4794 GDB can now write to executable and core files (e.g. patch
4795 a variable's value). You must turn this switch on, specify
4796 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4797 by assigning a new value to a variable. Modifications take
4800 * Automatic SunOS shared library reading
4802 When you run your program, GDB automatically determines where its
4803 shared libraries (if any) have been loaded, and reads their symbols.
4804 The `share' command is no longer needed. This also works when
4805 examining core files.
4809 You can specify the number of lines that the `list' command shows.
4812 * New machines supported (host and target)
4814 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4815 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4816 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4818 * New hosts supported (not targets)
4820 IBM RT/PC: romp-ibm-aix or rtpc
4822 * New targets supported (not hosts)
4824 AMD 29000 embedded with COFF a29k-none-coff
4825 AMD 29000 embedded with a.out a29k-none-aout
4826 Ultracomputer remote kernel debug a29k-nyu-kern
4828 * New remote interfaces
4834 *** Changes in GDB-4.0:
4838 Wide output is wrapped at good places to make the output more readable.
4840 Gdb now supports cross-debugging from a host machine of one type to a
4841 target machine of another type. Communication with the target system
4842 is over serial lines. The ``target'' command handles connecting to the
4843 remote system; the ``load'' command will download a program into the
4844 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4845 also supports debugging of realtime processes running under VxWorks,
4846 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4847 stub on the target system.
4849 New CPUs supported include the AMD 29000 and Intel 960.
4851 GDB now reads object files and symbol tables via a ``binary file''
4852 library, which allows a single copy of GDB to debug programs of multiple
4853 object file types such as a.out and coff.
4855 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4856 refcard.dvi and refcard.ps are available to format it).
4859 * Control-Variable user interface simplified
4861 All variables that control the operation of the debugger can be set
4862 by the ``set'' command, and displayed by the ``show'' command.
4864 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4865 ``Show prompt'' produces the response:
4866 Gdb's prompt is new-gdb=>.
4868 What follows are the NEW set commands. The command ``help set'' will
4869 print a complete list of old and new set commands. ``help set FOO''
4870 will give a longer description of the variable FOO. ``show'' will show
4871 all of the variable descriptions and their current settings.
4873 confirm on/off: Enables warning questions for operations that are
4874 hard to recover from, e.g. rerunning the program while
4875 it is already running. Default is ON.
4877 editing on/off: Enables EMACS style command line editing
4878 of input. Previous lines can be recalled with
4879 control-P, the current line can be edited with control-B,
4880 you can search for commands with control-R, etc.
4883 history filename NAME: NAME is where the gdb command history
4884 will be stored. The default is .gdb_history,
4885 or the value of the environment variable
4888 history size N: The size, in commands, of the command history. The
4889 default is 256, or the value of the environment variable
4892 history save on/off: If this value is set to ON, the history file will
4893 be saved after exiting gdb. If set to OFF, the
4894 file will not be saved. The default is OFF.
4896 history expansion on/off: If this value is set to ON, then csh-like
4897 history expansion will be performed on
4898 command line input. The default is OFF.
4900 radix N: Sets the default radix for input and output. It can be set
4901 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4902 in the current radix, so "set radix 10" is always a no-op.
4904 height N: This integer value is the number of lines on a page. Default
4905 is 24, the current `stty rows'' setting, or the ``li#''
4906 setting from the termcap entry matching the environment
4909 width N: This integer value is the number of characters on a line.
4910 Default is 80, the current `stty cols'' setting, or the ``co#''
4911 setting from the termcap entry matching the environment
4914 Note: ``set screensize'' is obsolete. Use ``set height'' and
4915 ``set width'' instead.
4917 print address on/off: Print memory addresses in various command displays,
4918 such as stack traces and structure values. Gdb looks
4919 more ``symbolic'' if you turn this off; it looks more
4920 ``machine level'' with it on. Default is ON.
4922 print array on/off: Prettyprint arrays. New convenient format! Default
4925 print demangle on/off: Print C++ symbols in "source" form if on,
4928 print asm-demangle on/off: Same, for assembler level printouts
4931 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4934 * Support for Epoch Environment.
4936 The epoch environment is a version of Emacs v18 with windowing. One
4937 new command, ``inspect'', is identical to ``print'', except that if you
4938 are running in the epoch environment, the value is printed in its own
4942 * Support for Shared Libraries
4944 GDB can now debug programs and core files that use SunOS shared libraries.
4945 Symbols from a shared library cannot be referenced
4946 before the shared library has been linked with the program (this
4947 happens after you type ``run'' and before the function main() is entered).
4948 At any time after this linking (including when examining core files
4949 from dynamically linked programs), gdb reads the symbols from each
4950 shared library when you type the ``sharedlibrary'' command.
4951 It can be abbreviated ``share''.
4953 sharedlibrary REGEXP: Load shared object library symbols for files
4954 matching a unix regular expression. No argument
4955 indicates to load symbols for all shared libraries.
4957 info sharedlibrary: Status of loaded shared libraries.
4962 A watchpoint stops execution of a program whenever the value of an
4963 expression changes. Checking for this slows down execution
4964 tremendously whenever you are in the scope of the expression, but is
4965 quite useful for catching tough ``bit-spreader'' or pointer misuse
4966 problems. Some machines such as the 386 have hardware for doing this
4967 more quickly, and future versions of gdb will use this hardware.
4969 watch EXP: Set a watchpoint (breakpoint) for an expression.
4971 info watchpoints: Information about your watchpoints.
4973 delete N: Deletes watchpoint number N (same as breakpoints).
4974 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4975 enable N: Re-enables watchpoint number N (same as breakpoints).
4978 * C++ multiple inheritance
4980 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4983 * C++ exception handling
4985 Gdb now supports limited C++ exception handling. Besides the existing
4986 ability to breakpoint on an exception handler, gdb can breakpoint on
4987 the raising of an exception (before the stack is peeled back to the
4990 catch FOO: If there is a FOO exception handler in the dynamic scope,
4991 set a breakpoint to catch exceptions which may be raised there.
4992 Multiple exceptions (``catch foo bar baz'') may be caught.
4994 info catch: Lists all exceptions which may be caught in the
4995 current stack frame.
4998 * Minor command changes
5000 The command ``call func (arg, arg, ...)'' now acts like the print
5001 command, except it does not print or save a value if the function's result
5002 is void. This is similar to dbx usage.
5004 The ``up'' and ``down'' commands now always print the frame they end up
5005 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5006 frames without printing.
5008 * New directory command
5010 'dir' now adds directories to the FRONT of the source search path.
5011 The path starts off empty. Source files that contain debug information
5012 about the directory in which they were compiled can be found even
5013 with an empty path; Sun CC and GCC include this information. If GDB can't
5014 find your source file in the current directory, type "dir .".
5016 * Configuring GDB for compilation
5018 For normal use, type ``./configure host''. See README or gdb.texinfo
5021 GDB now handles cross debugging. If you are remotely debugging between
5022 two different machines, type ``./configure host -target=targ''.
5023 Host is the machine where GDB will run; targ is the machine
5024 where the program that you are debugging will run.