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 Set a list of directories from which to load auto-loaded scripts.
195 Automatically loaded Python scripts and GDB scripts are located in one
196 of the directories listed by this option.
197 The delimiter (':' above) may differ according to the host platform.
199 set auto-load safe-path <dir1>[:<dir2>...]
200 show auto-load safe-path
201 Set a list of directories from which it is safe to auto-load files.
202 The delimiter (':' above) may differ according to the host platform.
204 set debug auto-load on|off
206 Control display of debugging info for auto-loading the files above.
208 set dprintf-style gdb|call
210 Control the way in which a dynamic printf is performed; "gdb" requests
211 a GDB printf command, while "call" causes dprintf to call a function
214 set dprintf-function <expr>
215 show dprintf-function
216 set dprintf-channel <expr>
218 Set the function and optional first argument to the call when using
219 the "call" style of dynamic printf.
221 * New configure options
224 Configure default value for the 'set auto-load scripts-directory'
225 setting above. It defaults to '$ddir/auto-load', $ddir representing
226 GDB's data directory (available via show data-directory).
228 --with-auto-load-safe-path
229 Configure default value for the 'set auto-load safe-path' setting
230 above. It defaults to the --with-auto-load-dir setting.
232 --without-auto-load-safe-path
233 Set 'set auto-load safe-path' to '/', effectively disabling this
238 z0/z1 conditional breakpoints extension
240 The z0/z1 breakpoint insertion packets have been extended to carry
241 a list of conditional expressions over to the remote stub depending on the
242 condition evaluation mode. The use of this extension can be controlled
243 via the "set remote conditional-breakpoints-packet" command.
247 Specify the signals which the remote stub may pass to the debugged
248 program without GDB involvement.
250 * New command line options
252 --init-command=FILE, -ix Like --command, -x but execute it
253 before loading inferior.
254 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
255 execute it before loading inferior.
257 *** Changes in GDB 7.4
259 * GDB now handles ambiguous linespecs more consistently; the existing
260 FILE:LINE support has been expanded to other types of linespecs. A
261 breakpoint will now be set on all matching locations in all
262 inferiors, and locations will be added or removed according to
265 * GDB now allows you to skip uninteresting functions and files when
266 stepping with the "skip function" and "skip file" commands.
268 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
269 and "show remote hardware-watchpoint-length-limit". These allows to
270 set or show the maximum length limit (in bytes) of a remote
271 target hardware watchpoint.
273 This allows e.g. to use "unlimited" hardware watchpoints with the
274 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
275 watchpoints are slower than real hardware watchpoints but are
276 significantly faster than gdb software watchpoints.
280 ** The register_pretty_printer function in module gdb.printing now takes
281 an optional `replace' argument. If True, the new printer replaces any
284 ** The "maint set python print-stack on|off" command has been
285 deprecated and will be deleted in GDB 7.5.
286 A new command: "set python print-stack none|full|message" has
287 replaced it. Additionally, the default for "print-stack" is
288 now "message", which just prints the error message without
291 ** A prompt substitution hook (prompt_hook) is now available to the
294 ** A new Python module, gdb.prompt has been added to the GDB Python
295 modules library. This module provides functionality for
296 escape sequences in prompts (used by set/show
297 extended-prompt). These escape sequences are replaced by their
300 ** Python commands and convenience-functions located in
301 'data-directory'/python/gdb/command and
302 'data-directory'/python/gdb/function are now automatically loaded
305 ** Blocks now provide four new attributes. global_block and
306 static_block will return the global and static blocks
307 respectively. is_static and is_global are boolean attributes
308 that indicate if the block is one of those two types.
310 ** Symbols now provide the "type" attribute, the type of the symbol.
312 ** The "gdb.breakpoint" function has been deprecated in favor of
315 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
316 of a function. This class is based on the "finish" command
317 available in the CLI.
319 ** Type objects for struct and union types now allow access to
320 the fields using standard Python dictionary (mapping) methods.
321 For example, "some_type['myfield']" now works, as does
324 ** A new event "gdb.new_objfile" has been added, triggered by loading a
327 ** A new function, "deep_items" has been added to the gdb.types
328 module in the GDB Python modules library. This function returns
329 an iterator over the fields of a struct or union type. Unlike
330 the standard Python "iteritems" method, it will recursively traverse
331 any anonymous fields.
335 ** "*stopped" events can report several new "reason"s, such as
338 ** Breakpoint changes are now notified using new async records, like
339 "=breakpoint-modified".
341 ** New command -ada-task-info.
343 * libthread-db-search-path now supports two special values: $sdir and $pdir.
344 $sdir specifies the default system locations of shared libraries.
345 $pdir specifies the directory where the libpthread used by the application
348 GDB no longer looks in $sdir and $pdir after it has searched the directories
349 mentioned in libthread-db-search-path. If you want to search those
350 directories, they must be specified in libthread-db-search-path.
351 The default value of libthread-db-search-path on GNU/Linux and Solaris
352 systems is now "$sdir:$pdir".
354 $pdir is not supported by gdbserver, it is currently ignored.
355 $sdir is supported by gdbserver.
357 * New configure option --with-iconv-bin.
358 When using the internationalization support like the one in the GNU C
359 library, GDB will invoke the "iconv" program to get a list of supported
360 character sets. If this program lives in a non-standard location, one can
361 use this option to specify where to find it.
363 * When natively debugging programs on PowerPC BookE processors running
364 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
365 watchpoints, which specify a mask in addition to an address to watch.
366 The mask specifies that some bits of an address (the bits which are
367 reset in the mask) should be ignored when matching the address accessed
368 by the inferior against the watchpoint address. See the "PowerPC Embedded"
369 section in the user manual for more details.
371 * The new option --once causes GDBserver to stop listening for connections once
372 the first connection is made. The listening port used by GDBserver will
373 become available after that.
375 * New commands "info macros" and "alias" have been added.
377 * New function parameters suffix @entry specifies value of function parameter
378 at the time the function got called. Entry values are available only since
384 "!" is now an alias of the "shell" command.
385 Note that no space is needed between "!" and SHELL COMMAND.
389 watch EXPRESSION mask MASK_VALUE
390 The watch command now supports the mask argument which allows creation
391 of masked watchpoints, if the current architecture supports this feature.
393 info auto-load-scripts [REGEXP]
394 This command was formerly named "maintenance print section-scripts".
395 It is now generally useful and is no longer a maintenance-only command.
397 info macro [-all] [--] MACRO
398 The info macro command has new options `-all' and `--'. The first for
399 printing all definitions of a macro. The second for explicitly specifying
400 the end of arguments and the beginning of the macro name in case the macro
401 name starts with a hyphen.
403 collect[/s] EXPRESSIONS
404 The tracepoint collect command now takes an optional modifier "/s"
405 that directs it to dereference pointer-to-character types and
406 collect the bytes of memory up to a zero byte. The behavior is
407 similar to what you see when you use the regular print command on a
408 string. An optional integer following the "/s" sets a bound on the
409 number of bytes that will be collected.
412 The trace start command now interprets any supplied arguments as a
413 note to be recorded with the trace run, with an effect similar to
414 setting the variable trace-notes.
417 The trace stop command now interprets any arguments as a note to be
418 mentioned along with the tstatus report that the trace was stopped
419 with a command. The effect is similar to setting the variable
422 * Tracepoints can now be enabled and disabled at any time after a trace
423 experiment has been started using the standard "enable" and "disable"
424 commands. It is now possible to start a trace experiment with no enabled
425 tracepoints; GDB will display a warning, but will allow the experiment to
426 begin, assuming that tracepoints will be enabled as needed while the trace
429 * Fast tracepoints on 32-bit x86-architectures can now be placed at
430 locations with 4-byte instructions, when they were previously
431 limited to locations with instructions of 5 bytes or longer.
437 Set the GDB prompt, and allow escape sequences to be inserted to
438 display miscellaneous information (see 'help set extended-prompt'
439 for the list of sequences). This prompt (and any information
440 accessed through the escape sequences) is updated every time the
443 set print entry-values (both|compact|default|if-needed|no|only|preferred)
444 show print entry-values
445 Set printing of frame argument values at function entry. In some cases
446 GDB can determine the value of function argument which was passed by the
447 function caller, even if the value was modified inside the called function.
449 set debug entry-values
450 show debug entry-values
451 Control display of debugging info for determining frame argument values at
452 function entry and virtual tail call frames.
454 set basenames-may-differ
455 show basenames-may-differ
456 Set whether a source file may have multiple base names.
457 (A "base name" is the name of a file with the directory part removed.
458 Example: The base name of "/home/user/hello.c" is "hello.c".)
459 If set, GDB will canonicalize file names (e.g., expand symlinks)
460 before comparing them. Canonicalization is an expensive operation,
461 but it allows the same file be known by more than one base name.
462 If not set (the default), all source files are assumed to have just
463 one base name, and gdb will do file name comparisons more efficiently.
469 Set a user name and notes for the current and any future trace runs.
470 This is useful for long-running and/or disconnected traces, to
471 inform others (or yourself) as to who is running the trace, supply
472 contact information, or otherwise explain what is going on.
475 show trace-stop-notes
476 Set a note attached to the trace run, that is displayed when the
477 trace has been stopped by a tstop command. This is useful for
478 instance as an explanation, if you are stopping a trace run that was
479 started by someone else.
485 Dynamically enable a tracepoint in a started trace experiment.
489 Dynamically disable a tracepoint in a started trace experiment.
493 Set the user and notes of the trace run.
497 Query the current status of a tracepoint.
501 Query the minimum length of instruction at which a fast tracepoint may
504 * Dcache size (number of lines) and line-size are now runtime-configurable
505 via "set dcache line" and "set dcache line-size" commands.
509 Texas Instruments TMS320C6x tic6x-*-*
513 Renesas RL78 rl78-*-elf
515 *** Changes in GDB 7.3.1
517 * The build failure for NetBSD and OpenBSD targets have now been fixed.
519 *** Changes in GDB 7.3
521 * GDB has a new command: "thread find [REGEXP]".
522 It finds the thread id whose name, target id, or thread extra info
523 matches the given regular expression.
525 * The "catch syscall" command now works on mips*-linux* targets.
527 * The -data-disassemble MI command now supports modes 2 and 3 for
528 dumping the instruction opcodes.
530 * New command line options
532 -data-directory DIR Specify DIR as the "data-directory".
533 This is mostly for testing purposes.
535 * The "maint set python auto-load on|off" command has been renamed to
536 "set auto-load-scripts on|off".
538 * GDB has a new command: "set directories".
539 It is like the "dir" command except that it replaces the
540 source path list instead of augmenting it.
542 * GDB now understands thread names.
544 On GNU/Linux, "info threads" will display the thread name as set by
545 prctl or pthread_setname_np.
547 There is also a new command, "thread name", which can be used to
548 assign a name internally for GDB to display.
551 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
552 has been integrated into GDB.
556 ** The function gdb.Write now accepts an optional keyword 'stream'.
557 This keyword, when provided, will direct the output to either
558 stdout, stderr, or GDB's logging output.
560 ** Parameters can now be be sub-classed in Python, and in particular
561 you may implement the get_set_doc and get_show_doc functions.
562 This improves how Parameter set/show documentation is processed
563 and allows for more dynamic content.
565 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
566 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
567 have an is_valid method.
569 ** Breakpoints can now be sub-classed in Python, and in particular
570 you may implement a 'stop' function that is executed each time
571 the inferior reaches that breakpoint.
573 ** New function gdb.lookup_global_symbol looks up a global symbol.
575 ** GDB values in Python are now callable if the value represents a
576 function. For example, if 'some_value' represents a function that
577 takes two integer parameters and returns a value, you can call
578 that function like so:
580 result = some_value (10,20)
582 ** Module gdb.types has been added.
583 It contains a collection of utilities for working with gdb.Types objects:
584 get_basic_type, has_field, make_enum_dict.
586 ** Module gdb.printing has been added.
587 It contains utilities for writing and registering pretty-printers.
588 New classes: PrettyPrinter, SubPrettyPrinter,
589 RegexpCollectionPrettyPrinter.
590 New function: register_pretty_printer.
592 ** New commands "info pretty-printers", "enable pretty-printer" and
593 "disable pretty-printer" have been added.
595 ** gdb.parameter("directories") is now available.
597 ** New function gdb.newest_frame returns the newest frame in the
600 ** The gdb.InferiorThread class has a new "name" attribute. This
601 holds the thread's name.
603 ** Python Support for Inferior events.
604 Python scripts can add observers to be notified of events
605 occurring in the process being debugged.
606 The following events are currently supported:
607 - gdb.events.cont Continue event.
608 - gdb.events.exited Inferior exited event.
609 - gdb.events.stop Signal received, and Breakpoint hit events.
613 ** GDB now puts template parameters in scope when debugging in an
614 instantiation. For example, if you have:
616 template<int X> int func (void) { return X; }
618 then if you step into func<5>, "print X" will show "5". This
619 feature requires proper debuginfo support from the compiler; it
620 was added to GCC 4.5.
622 ** The motion commands "next", "finish", "until", and "advance" now
623 work better when exceptions are thrown. In particular, GDB will
624 no longer lose control of the inferior; instead, the GDB will
625 stop the inferior at the point at which the exception is caught.
626 This functionality requires a change in the exception handling
627 code that was introduced in GCC 4.5.
629 * GDB now follows GCC's rules on accessing volatile objects when
630 reading or writing target state during expression evaluation.
631 One notable difference to prior behavior is that "print x = 0"
632 no longer generates a read of x; the value of the assignment is
633 now always taken directly from the value being assigned.
635 * GDB now has some support for using labels in the program's source in
636 linespecs. For instance, you can use "advance label" to continue
637 execution to a label.
639 * GDB now has support for reading and writing a new .gdb_index
640 section. This section holds a fast index of DWARF debugging
641 information and can be used to greatly speed up GDB startup and
642 operation. See the documentation for `save gdb-index' for details.
644 * The "watch" command now accepts an optional "-location" argument.
645 When used, this causes GDB to watch the memory referred to by the
646 expression. Such a watchpoint is never deleted due to it going out
649 * GDB now supports thread debugging of core dumps on GNU/Linux.
651 GDB now activates thread debugging using the libthread_db library
652 when debugging GNU/Linux core dumps, similarly to when debugging
653 live processes. As a result, when debugging a core dump file, GDB
654 is now able to display pthread_t ids of threads. For example, "info
655 threads" shows the same output as when debugging the process when it
656 was live. In earlier releases, you'd see something like this:
659 * 1 LWP 6780 main () at main.c:10
661 While now you see this:
664 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
666 It is also now possible to inspect TLS variables when debugging core
669 When debugging a core dump generated on a machine other than the one
670 used to run GDB, you may need to point GDB at the correct
671 libthread_db library with the "set libthread-db-search-path"
672 command. See the user manual for more details on this command.
674 * When natively debugging programs on PowerPC BookE processors running
675 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
676 which stop execution of the inferior whenever it executes an instruction
677 at any address within the specified range. See the "PowerPC Embedded"
678 section in the user manual for more details.
680 * New features in the GDB remote stub, GDBserver
682 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
683 and i686 LynxOS (version 5.x).
685 ** GDBserver is now supported on Blackfin Linux.
687 * New native configurations
689 ia64 HP-UX ia64-*-hpux*
693 Analog Devices, Inc. Blackfin Processor bfin-*
695 * Ada task switching is now supported on sparc-elf targets when
696 debugging a program using the Ravenscar Profile. For more information,
697 see the "Tasking Support when using the Ravenscar Profile" section
698 in the GDB user manual.
700 * Guile support was removed.
702 * New features in the GNU simulator
704 ** The --map-info flag lists all known core mappings.
706 ** CFI flashes may be simulated via the "cfi" device.
708 *** Changes in GDB 7.2
710 * Shared library support for remote targets by default
712 When GDB is configured for a generic, non-OS specific target, like
713 for example, --target=arm-eabi or one of the many *-*-elf targets,
714 GDB now queries remote stubs for loaded shared libraries using the
715 `qXfer:libraries:read' packet. Previously, shared library support
716 was always disabled for such configurations.
720 ** Argument Dependent Lookup (ADL)
722 In C++ ADL lookup directs function search to the namespaces of its
723 arguments even if the namespace has not been imported.
733 Here the compiler will search for `foo' in the namespace of 'b'
734 and find A::foo. GDB now supports this. This construct is commonly
735 used in the Standard Template Library for operators.
737 ** Improved User Defined Operator Support
739 In addition to member operators, GDB now supports lookup of operators
740 defined in a namespace and imported with a `using' directive, operators
741 defined in the global scope, operators imported implicitly from an
742 anonymous namespace, and the ADL operators mentioned in the previous
744 GDB now also supports proper overload resolution for all the previously
745 mentioned flavors of operators.
747 ** static const class members
749 Printing of static const class members that are initialized in the
750 class definition has been fixed.
752 * Windows Thread Information Block access.
754 On Windows targets, GDB now supports displaying the Windows Thread
755 Information Block (TIB) structure. This structure is visible either
756 by using the new command `info w32 thread-information-block' or, by
757 dereferencing the new convenience variable named `$_tlb', a
758 thread-specific pointer to the TIB. This feature is also supported
759 when remote debugging using GDBserver.
763 Static tracepoints are calls in the user program into a tracing
764 library. One such library is a port of the LTTng kernel tracer to
765 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
766 When debugging with GDBserver, GDB now supports combining the GDB
767 tracepoint machinery with such libraries. For example: the user can
768 use GDB to probe a static tracepoint marker (a call from the user
769 program into the tracing library) with the new "strace" command (see
770 "New commands" below). This creates a "static tracepoint" in the
771 breakpoint list, that can be manipulated with the same feature set
772 as fast and regular tracepoints. E.g., collect registers, local and
773 global variables, collect trace state variables, and define
774 tracepoint conditions. In addition, the user can collect extra
775 static tracepoint marker specific data, by collecting the new
776 $_sdata internal variable. When analyzing the trace buffer, you can
777 inspect $_sdata like any other variable available to GDB. For more
778 information, see the "Tracepoints" chapter in GDB user manual. New
779 remote packets have been defined to support static tracepoints, see
780 the "New remote packets" section below.
782 * Better reconstruction of tracepoints after disconnected tracing
784 GDB will attempt to download the original source form of tracepoint
785 definitions when starting a trace run, and then will upload these
786 upon reconnection to the target, resulting in a more accurate
787 reconstruction of the tracepoints that are in use on the target.
791 You can now exercise direct control over the ways that GDB can
792 affect your program. For instance, you can disallow the setting of
793 breakpoints, so that the program can run continuously (assuming
794 non-stop mode). In addition, the "observer" variable is available
795 to switch all of the different controls; in observer mode, GDB
796 cannot affect the target's behavior at all, which is useful for
797 tasks like diagnosing live systems in the field.
799 * The new convenience variable $_thread holds the number of the
806 Return the address of the Windows Thread Information Block of a given thread.
810 In response to several of the tracepoint packets, the target may now
811 also respond with a number of intermediate `qRelocInsn' request
812 packets before the final result packet, to have GDB handle
813 relocating an instruction to execute at a different address. This
814 is particularly useful for stubs that support fast tracepoints. GDB
815 reports support for this feature in the qSupported packet.
819 List static tracepoint markers in the target program.
823 List static tracepoint markers at a given address in the target
826 qXfer:statictrace:read
828 Read the static trace data collected (by a `collect $_sdata'
829 tracepoint action). The remote stub reports support for this packet
830 to gdb's qSupported query.
834 Send the current settings of GDB's permission flags.
838 Send part of the source (textual) form of a tracepoint definition,
839 which includes location, conditional, and action list.
841 * The source command now accepts a -s option to force searching for the
842 script in the source search path even if the script name specifies
845 * New features in the GDB remote stub, GDBserver
847 - GDBserver now support tracepoints (including fast tracepoints, and
848 static tracepoints). The feature is currently supported by the
849 i386-linux and amd64-linux builds. See the "Tracepoints support
850 in gdbserver" section in the manual for more information.
852 GDBserver JIT compiles the tracepoint's conditional agent
853 expression bytecode into native code whenever possible for low
854 overhead dynamic tracepoints conditionals. For such tracepoints,
855 an expression that examines program state is evaluated when the
856 tracepoint is reached, in order to determine whether to capture
857 trace data. If the condition is simple and false, processing the
858 tracepoint finishes very quickly and no data is gathered.
860 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
861 for static tracepoints support.
863 - GDBserver now supports x86_64 Windows 64-bit debugging.
865 * GDB now sends xmlRegisters= in qSupported packet to indicate that
866 it understands register description.
868 * The --batch flag now disables pagination and queries.
870 * X86 general purpose registers
872 GDB now supports reading/writing byte, word and double-word x86
873 general purpose registers directly. This means you can use, say,
874 $ah or $ax to refer, respectively, to the byte register AH and
875 16-bit word register AX that are actually portions of the 32-bit
876 register EAX or 64-bit register RAX.
878 * The `commands' command now accepts a range of breakpoints to modify.
879 A plain `commands' following a command that creates multiple
880 breakpoints affects all the breakpoints set by that command. This
881 applies to breakpoints set by `rbreak', and also applies when a
882 single `break' command creates multiple breakpoints (e.g.,
883 breakpoints on overloaded c++ functions).
885 * The `rbreak' command now accepts a filename specification as part of
886 its argument, limiting the functions selected by the regex to those
887 in the specified file.
889 * Support for remote debugging Windows and SymbianOS shared libraries
890 from Unix hosts has been improved. Non Windows GDB builds now can
891 understand target reported file names that follow MS-DOS based file
892 system semantics, such as file names that include drive letters and
893 use the backslash character as directory separator. This makes it
894 possible to transparently use the "set sysroot" and "set
895 solib-search-path" on Unix hosts to point as host copies of the
896 target's shared libraries. See the new command "set
897 target-file-system-kind" described below, and the "Commands to
898 specify files" section in the user manual for more information.
902 eval template, expressions...
903 Convert the values of one or more expressions under the control
904 of the string template to a command line, and call it.
906 set target-file-system-kind unix|dos-based|auto
907 show target-file-system-kind
908 Set or show the assumed file system kind for target reported file
911 save breakpoints <filename>
912 Save all current breakpoint definitions to a file suitable for use
913 in a later debugging session. To read the saved breakpoint
914 definitions, use the `source' command.
916 `save tracepoints' is a new alias for `save-tracepoints'. The latter
919 info static-tracepoint-markers
920 Display information about static tracepoint markers in the target.
922 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
923 Define a static tracepoint by probing a marker at the given
924 function, line, address, or marker ID.
928 Enable and disable observer mode.
930 set may-write-registers on|off
931 set may-write-memory on|off
932 set may-insert-breakpoints on|off
933 set may-insert-tracepoints on|off
934 set may-insert-fast-tracepoints on|off
935 set may-interrupt on|off
936 Set individual permissions for GDB effects on the target. Note that
937 some of these settings can have undesirable or surprising
938 consequences, particularly when changed in the middle of a session.
939 For instance, disabling the writing of memory can prevent
940 breakpoints from being inserted, cause single-stepping to fail, or
941 even crash your program, if you disable after breakpoints have been
942 inserted. However, GDB should not crash.
944 set record memory-query on|off
945 show record memory-query
946 Control whether to stop the inferior if memory changes caused
947 by an instruction cannot be recorded.
952 The disassemble command now supports "start,+length" form of two arguments.
956 ** GDB now provides a new directory location, called the python directory,
957 where Python scripts written for GDB can be installed. The location
958 of that directory is <data-directory>/python, where <data-directory>
959 is the GDB data directory. For more details, see section `Scripting
960 GDB using Python' in the manual.
962 ** The GDB Python API now has access to breakpoints, symbols, symbol
963 tables, program spaces, inferiors, threads and frame's code blocks.
964 Additionally, GDB Parameters can now be created from the API, and
965 manipulated via set/show in the CLI.
967 ** New functions gdb.target_charset, gdb.target_wide_charset,
968 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
970 ** New exception gdb.GdbError.
972 ** Pretty-printers are now also looked up in the current program space.
974 ** Pretty-printers can now be individually enabled and disabled.
976 ** GDB now looks for names of Python scripts to auto-load in a
977 special section named `.debug_gdb_scripts', in addition to looking
978 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
980 * Tracepoint actions were unified with breakpoint commands. In particular,
981 there are no longer differences in "info break" output for breakpoints and
982 tracepoints and the "commands" command can be used for both tracepoints and
987 ARM Symbian arm*-*-symbianelf*
989 * D language support.
990 GDB now supports debugging programs written in the D programming
993 * GDB now supports the extended ptrace interface for PowerPC which is
994 available since Linux kernel version 2.6.34. This automatically enables
995 any hardware breakpoints and additional hardware watchpoints available in
996 the processor. The old ptrace interface exposes just one hardware
997 watchpoint and no hardware breakpoints.
999 * GDB is now able to use the Data Value Compare (DVC) register available on
1000 embedded PowerPC processors to implement in hardware simple watchpoint
1001 conditions of the form:
1003 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1005 This works in native GDB running on Linux kernels with the extended ptrace
1006 interface mentioned above.
1008 *** Changes in GDB 7.1
1012 ** Namespace Support
1014 GDB now supports importing of namespaces in C++. This enables the
1015 user to inspect variables from imported namespaces. Support for
1016 namepace aliasing has also been added. So, if a namespace is
1017 aliased in the current scope (e.g. namepace C=A; ) the user can
1018 print variables using the alias (e.g. (gdb) print C::x).
1022 All known bugs relating to the printing of virtual base class were
1023 fixed. It is now possible to call overloaded static methods using a
1028 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1029 and reinterpret_cast<> are now handled by the C++ expression parser.
1033 Xilinx MicroBlaze microblaze-*-*
1038 Xilinx MicroBlaze microblaze
1041 * Multi-program debugging.
1043 GDB now has support for multi-program (a.k.a. multi-executable or
1044 multi-exec) debugging. This allows for debugging multiple inferiors
1045 simultaneously each running a different program under the same GDB
1046 session. See "Debugging Multiple Inferiors and Programs" in the
1047 manual for more information. This implied some user visible changes
1048 in the multi-inferior support. For example, "info inferiors" now
1049 lists inferiors that are not running yet or that have exited
1050 already. See also "New commands" and "New options" below.
1052 * New tracing features
1054 GDB's tracepoint facility now includes several new features:
1056 ** Trace state variables
1058 GDB tracepoints now include support for trace state variables, which
1059 are variables managed by the target agent during a tracing
1060 experiment. They are useful for tracepoints that trigger each
1061 other, so for instance one tracepoint can count hits in a variable,
1062 and then a second tracepoint has a condition that is true when the
1063 count reaches a particular value. Trace state variables share the
1064 $-syntax of GDB convenience variables, and can appear in both
1065 tracepoint actions and condition expressions. Use the "tvariable"
1066 command to create, and "info tvariables" to view; see "Trace State
1067 Variables" in the manual for more detail.
1071 GDB now includes an option for defining fast tracepoints, which
1072 targets may implement more efficiently, such as by installing a jump
1073 into the target agent rather than a trap instruction. The resulting
1074 speedup can be by two orders of magnitude or more, although the
1075 tradeoff is that some program locations on some target architectures
1076 might not allow fast tracepoint installation, for instance if the
1077 instruction to be replaced is shorter than the jump. To request a
1078 fast tracepoint, use the "ftrace" command, with syntax identical to
1079 the regular trace command.
1081 ** Disconnected tracing
1083 It is now possible to detach GDB from the target while it is running
1084 a trace experiment, then reconnect later to see how the experiment
1085 is going. In addition, a new variable disconnected-tracing lets you
1086 tell the target agent whether to continue running a trace if the
1087 connection is lost unexpectedly.
1091 GDB now has the ability to save the trace buffer into a file, and
1092 then use that file as a target, similarly to you can do with
1093 corefiles. You can select trace frames, print data that was
1094 collected in them, and use tstatus to display the state of the
1095 tracing run at the moment that it was saved. To create a trace
1096 file, use "tsave <filename>", and to use it, do "target tfile
1099 ** Circular trace buffer
1101 You can ask the target agent to handle the trace buffer as a
1102 circular buffer, discarding the oldest trace frames to make room for
1103 newer ones, by setting circular-trace-buffer to on. This feature may
1104 not be available for all target agents.
1109 The disassemble command, when invoked with two arguments, now requires
1110 the arguments to be comma-separated.
1113 The info variables command now displays variable definitions. Files
1114 which only declare a variable are not shown.
1117 The source command is now capable of sourcing Python scripts.
1118 This feature is dependent on the debugger being build with Python
1121 Related to this enhancement is also the introduction of a new command
1122 "set script-extension" (see below).
1124 * New commands (for set/show, see "New options" below)
1126 record save [<FILENAME>]
1127 Save a file (in core file format) containing the process record
1128 execution log for replay debugging at a later time.
1130 record restore <FILENAME>
1131 Restore the process record execution log that was saved at an
1132 earlier time, for replay debugging.
1134 add-inferior [-copies <N>] [-exec <FILENAME>]
1137 clone-inferior [-copies <N>] [ID]
1138 Make a new inferior ready to execute the same program another
1139 inferior has loaded.
1144 maint info program-spaces
1145 List the program spaces loaded into GDB.
1147 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1148 show remote interrupt-sequence
1149 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1150 as the sequence to the remote target in order to interrupt the execution.
1151 Ctrl-C is a default. Some system prefers BREAK which is high level of
1152 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1153 Magic SysRq g. It is BREAK signal and character 'g'.
1155 set remote interrupt-on-connect [on | off]
1156 show remote interrupt-on-connect
1157 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1158 remote target when gdb connects to it. This is needed when you debug
1161 set remotebreak [on | off]
1163 Deprecated. Use "set/show remote interrupt-sequence" instead.
1165 tvariable $NAME [ = EXP ]
1166 Create or modify a trace state variable.
1169 List trace state variables and their values.
1171 delete tvariable $NAME ...
1172 Delete one or more trace state variables.
1175 Evaluate the given expressions without collecting anything into the
1176 trace buffer. (Valid in tracepoint actions only.)
1178 ftrace FN / FILE:LINE / *ADDR
1179 Define a fast tracepoint at the given function, line, or address.
1181 * New expression syntax
1183 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1184 GDB now parses 0b101010 identically with 42.
1188 set follow-exec-mode new|same
1189 show follow-exec-mode
1190 Control whether GDB reuses the same inferior across an exec call or
1191 creates a new one. This is useful to be able to restart the old
1192 executable after the inferior having done an exec call.
1194 set default-collect EXPR, ...
1195 show default-collect
1196 Define a list of expressions to be collected at each tracepoint.
1197 This is a useful way to ensure essential items are not overlooked,
1198 such as registers or a critical global variable.
1200 set disconnected-tracing
1201 show disconnected-tracing
1202 If set to 1, the target is instructed to continue tracing if it
1203 loses its connection to GDB. If 0, the target is to stop tracing
1206 set circular-trace-buffer
1207 show circular-trace-buffer
1208 If set to on, the target is instructed to use a circular trace buffer
1209 and discard the oldest trace frames instead of stopping the trace due
1210 to a full trace buffer. If set to off, the trace stops when the buffer
1211 fills up. Some targets may not support this.
1213 set script-extension off|soft|strict
1214 show script-extension
1215 If set to "off", the debugger does not perform any script language
1216 recognition, and all sourced files are assumed to be GDB scripts.
1217 If set to "soft" (the default), files are sourced according to
1218 filename extension, falling back to GDB scripts if the first
1220 If set to "strict", files are sourced according to filename extension.
1222 set ada trust-PAD-over-XVS on|off
1223 show ada trust-PAD-over-XVS
1224 If off, activate a workaround against a bug in the debugging information
1225 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1226 the GCC sources for more information about the GNAT encoding and
1227 PAD types in particular). It is always safe to set this option to
1228 off, but this introduces a slight performance penalty. The default
1231 * Python API Improvements
1233 ** GDB provides the new class gdb.LazyString. This is useful in
1234 some pretty-printing cases. The new method gdb.Value.lazy_string
1235 provides a simple way to create objects of this type.
1237 ** The fields returned by gdb.Type.fields now have an
1238 `is_base_class' attribute.
1240 ** The new method gdb.Type.range returns the range of an array type.
1242 ** The new method gdb.parse_and_eval can be used to parse and
1243 evaluate an expression.
1245 * New remote packets
1248 Define a trace state variable.
1251 Get the current value of a trace state variable.
1254 Set desired tracing behavior upon disconnection.
1257 Set the trace buffer to be linear or circular.
1260 Get data about the tracepoints currently in use.
1264 Process record now works correctly with hardware watchpoints.
1266 Multiple bug fixes have been made to the mips-irix port, making it
1267 much more reliable. In particular:
1268 - Debugging threaded applications is now possible again. Previously,
1269 GDB would hang while starting the program, or while waiting for
1270 the program to stop at a breakpoint.
1271 - Attaching to a running process no longer hangs.
1272 - An error occurring while loading a core file has been fixed.
1273 - Changing the value of the PC register now works again. This fixes
1274 problems observed when using the "jump" command, or when calling
1275 a function from GDB, or even when assigning a new value to $pc.
1276 - With the "finish" and "return" commands, the return value for functions
1277 returning a small array is now correctly printed.
1278 - It is now possible to break on shared library code which gets executed
1279 during a shared library init phase (code executed while executing
1280 their .init section). Previously, the breakpoint would have no effect.
1281 - GDB is now able to backtrace through the signal handler for
1282 non-threaded programs.
1284 PIE (Position Independent Executable) programs debugging is now supported.
1285 This includes debugging execution of PIC (Position Independent Code) shared
1286 libraries although for that, it should be possible to run such libraries as an
1289 *** Changes in GDB 7.0
1291 * GDB now has an interface for JIT compilation. Applications that
1292 dynamically generate code can create symbol files in memory and register
1293 them with GDB. For users, the feature should work transparently, and
1294 for JIT developers, the interface is documented in the GDB manual in the
1295 "JIT Compilation Interface" chapter.
1297 * Tracepoints may now be conditional. The syntax is as for
1298 breakpoints; either an "if" clause appended to the "trace" command,
1299 or the "condition" command is available. GDB sends the condition to
1300 the target for evaluation using the same bytecode format as is used
1301 for tracepoint actions.
1303 * The disassemble command now supports: an optional /r modifier, print the
1304 raw instructions in hex as well as in symbolic form, and an optional /m
1305 modifier to print mixed source+assembly.
1307 * Process record and replay
1309 In a architecture environment that supports ``process record and
1310 replay'', ``process record and replay'' target can record a log of
1311 the process execution, and replay it with both forward and reverse
1314 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1315 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1316 set execution-direction {forward|reverse}, for targets that support
1319 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1320 feature is available with a native GDB running on kernel version
1323 * GDB now has support for multi-byte and wide character sets on the
1324 target. Strings whose character type is wchar_t, char16_t, or
1325 char32_t are now correctly printed. GDB supports wide- and unicode-
1326 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1327 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1328 `printf'. This feature requires iconv to work properly; if your
1329 system does not have a working iconv, GDB can use GNU libiconv. See
1330 the installation instructions for more information.
1332 * GDB now supports automatic retrieval of shared library files from
1333 remote targets. To use this feature, specify a system root that begins
1334 with the `remote:' prefix, either via the `set sysroot' command or via
1335 the `--with-sysroot' configure-time option.
1337 * "info sharedlibrary" now takes an optional regex of libraries to show,
1338 and it now reports if a shared library has no debugging information.
1340 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1341 now complete on file names.
1343 * When completing in expressions, gdb will attempt to limit
1344 completions to allowable structure or union fields, where appropriate.
1345 For instance, consider:
1347 # struct example { int f1; double f2; };
1348 # struct example variable;
1351 If the user types TAB at the end of this command line, the available
1352 completions will be "f1" and "f2".
1354 * Inlined functions are now supported. They show up in backtraces, and
1355 the "step", "next", and "finish" commands handle them automatically.
1357 * GDB now supports the token-splicing (##) and stringification (#)
1358 operators when expanding macros. It also supports variable-arity
1361 * GDB now supports inspecting extra signal information, exported by
1362 the new $_siginfo convenience variable. The feature is currently
1363 implemented on linux ARM, i386 and amd64.
1365 * GDB can now display the VFP floating point registers and NEON vector
1366 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1367 can provide these registers (requires Linux 2.6.30 or later). Remote
1368 and simulator targets may also provide them.
1370 * New remote packets
1373 Search memory for a sequence of bytes.
1376 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1377 operation over reliable transport links. Use of this packet is
1378 controlled by the `set remote noack-packet' command.
1381 Kill the process with the specified process ID. Use this in preference
1382 to `k' when multiprocess protocol extensions are supported.
1385 Obtains additional operating system information
1389 Read or write additional signal information.
1391 * Removed remote protocol undocumented extension
1393 An undocumented extension to the remote protocol's `S' stop reply
1394 packet that permited the stub to pass a process id was removed.
1395 Remote servers should use the `T' stop reply packet instead.
1397 * GDB now supports multiple function calling conventions according to the
1398 DWARF-2 DW_AT_calling_convention function attribute.
1400 * The SH target utilizes the aforementioned change to distinguish between gcc
1401 and Renesas calling convention. It also adds the new CLI commands
1402 `set/show sh calling-convention'.
1404 * GDB can now read compressed debug sections, as produced by GNU gold
1405 with the --compress-debug-sections=zlib flag.
1407 * 64-bit core files are now supported on AIX.
1409 * Thread switching is now supported on Tru64.
1411 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1412 which will be allocated using malloc later in program execution.
1414 * The qXfer:libraries:read remote procotol packet now allows passing a
1415 list of section offsets.
1417 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1418 conditions handling signals delivered during attach or thread creation
1419 have also been fixed.
1421 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1422 From the user's standpoint, all unqualified instances of True and False
1423 are treated as the standard definitions, regardless of context.
1425 * GDB now parses C++ symbol and type names more flexibly. For
1428 template<typename T> class C { };
1431 GDB will now correctly handle all of:
1433 ptype C<char const *>
1434 ptype C<char const*>
1435 ptype C<const char *>
1436 ptype C<const char*>
1438 * New features in the GDB remote stub, gdbserver
1440 - The "--wrapper" command-line argument tells gdbserver to use a
1441 wrapper program to launch programs for debugging.
1443 - On PowerPC and S/390 targets, it is now possible to use a single
1444 gdbserver executable to debug both 32-bit and 64-bit programs.
1445 (This requires gdbserver itself to be built as a 64-bit executable.)
1447 - gdbserver uses the new noack protocol mode for TCP connections to
1448 reduce communications latency, if also supported and enabled in GDB.
1450 - Support for the sparc64-linux-gnu target is now included in
1453 - The amd64-linux build of gdbserver now supports debugging both
1454 32-bit and 64-bit programs.
1456 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1457 now support hardware watchpoints, and will use them automatically
1462 GDB now has support for scripting using Python. Whether this is
1463 available is determined at configure time.
1465 New GDB commands can now be written in Python.
1467 * Ada tasking support
1469 Ada tasks can now be inspected in GDB. The following commands have
1473 Print the list of Ada tasks.
1475 Print detailed information about task number N.
1477 Print the task number of the current task.
1479 Switch the context of debugging to task number N.
1481 * Support for user-defined prefixed commands. The "define" command can
1482 add new commands to existing prefixes, e.g. "target".
1484 * Multi-inferior, multi-process debugging.
1486 GDB now has generalized support for multi-inferior debugging. See
1487 "Debugging Multiple Inferiors" in the manual for more information.
1488 Although availability still depends on target support, the command
1489 set is more uniform now. The GNU/Linux specific multi-forks support
1490 has been migrated to this new framework. This implied some user
1491 visible changes; see "New commands" and also "Removed commands"
1494 * Target descriptions can now describe the target OS ABI. See the
1495 "Target Description Format" section in the user manual for more
1498 * Target descriptions can now describe "compatible" architectures
1499 to indicate that the target can execute applications for a different
1500 architecture in addition to those for the main target architecture.
1501 See the "Target Description Format" section in the user manual for
1504 * Multi-architecture debugging.
1506 GDB now includes general supports for debugging applications on
1507 hybrid systems that use more than one single processor architecture
1508 at the same time. Each such hybrid architecture still requires
1509 specific support to be added. The only hybrid architecture supported
1510 in this version of GDB is the Cell Broadband Engine.
1512 * GDB now supports integrated debugging of Cell/B.E. applications that
1513 use both the PPU and SPU architectures. To enable support for hybrid
1514 Cell/B.E. debugging, you need to configure GDB to support both the
1515 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1516 --enable-targets configure option.
1518 * Non-stop mode debugging.
1520 For some targets, GDB now supports an optional mode of operation in
1521 which you can examine stopped threads while other threads continue
1522 to execute freely. This is referred to as non-stop mode, with the
1523 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1524 section in the user manual for more information.
1526 To be able to support remote non-stop debugging, a remote stub needs
1527 to implement the non-stop mode remote protocol extensions, as
1528 described in the "Remote Non-Stop" section of the user manual. The
1529 GDB remote stub, gdbserver, has been adjusted to support these
1530 extensions on linux targets.
1532 * New commands (for set/show, see "New options" below)
1534 catch syscall [NAME(S) | NUMBER(S)]
1535 Catch system calls. Arguments, which should be names of system
1536 calls or their numbers, mean catch only those syscalls. Without
1537 arguments, every syscall will be caught. When the inferior issues
1538 any of the specified syscalls, GDB will stop and announce the system
1539 call, both when it is called and when its call returns. This
1540 feature is currently available with a native GDB running on the
1541 Linux Kernel, under the following architectures: x86, x86_64,
1542 PowerPC and PowerPC64.
1544 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1546 Search memory for a sequence of bytes.
1548 maint set python print-stack
1549 maint show python print-stack
1550 Show a stack trace when an error is encountered in a Python script.
1553 Invoke CODE by passing it to the Python interpreter.
1558 These allow macros to be defined, undefined, and listed
1562 Show operating system information about processes.
1565 List the inferiors currently under GDB's control.
1568 Switch focus to inferior number NUM.
1571 Detach from inferior number NUM.
1574 Kill inferior number NUM.
1578 set spu stop-on-load
1579 show spu stop-on-load
1580 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1582 set spu auto-flush-cache
1583 show spu auto-flush-cache
1584 Control whether to automatically flush the software-managed cache
1585 during Cell/B.E. debugging.
1587 set sh calling-convention
1588 show sh calling-convention
1589 Control the calling convention used when calling SH target functions.
1592 show debug timestamp
1593 Control display of timestamps with GDB debugging output.
1595 set disassemble-next-line
1596 show disassemble-next-line
1597 Control display of disassembled source lines or instructions when
1600 set remote noack-packet
1601 show remote noack-packet
1602 Set/show the use of remote protocol QStartNoAckMode packet. See above
1603 under "New remote packets."
1605 set remote query-attached-packet
1606 show remote query-attached-packet
1607 Control use of remote protocol `qAttached' (query-attached) packet.
1609 set remote read-siginfo-object
1610 show remote read-siginfo-object
1611 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1614 set remote write-siginfo-object
1615 show remote write-siginfo-object
1616 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1619 set remote reverse-continue
1620 show remote reverse-continue
1621 Control use of remote protocol 'bc' (reverse-continue) packet.
1623 set remote reverse-step
1624 show remote reverse-step
1625 Control use of remote protocol 'bs' (reverse-step) packet.
1627 set displaced-stepping
1628 show displaced-stepping
1629 Control displaced stepping mode. Displaced stepping is a way to
1630 single-step over breakpoints without removing them from the debuggee.
1631 Also known as "out-of-line single-stepping".
1634 show debug displaced
1635 Control display of debugging info for displaced stepping.
1637 maint set internal-error
1638 maint show internal-error
1639 Control what GDB does when an internal error is detected.
1641 maint set internal-warning
1642 maint show internal-warning
1643 Control what GDB does when an internal warning is detected.
1648 Use a wrapper program to launch programs for debugging.
1650 set multiple-symbols (all|ask|cancel)
1651 show multiple-symbols
1652 The value of this variable can be changed to adjust the debugger behavior
1653 when an expression or a breakpoint location contains an ambiguous symbol
1654 name (an overloaded function name, for instance).
1656 set breakpoint always-inserted
1657 show breakpoint always-inserted
1658 Keep breakpoints always inserted in the target, as opposed to inserting
1659 them when resuming the target, and removing them when the target stops.
1660 This option can improve debugger performance on slow remote targets.
1662 set arm fallback-mode (arm|thumb|auto)
1663 show arm fallback-mode
1664 set arm force-mode (arm|thumb|auto)
1666 These commands control how ARM GDB determines whether instructions
1667 are ARM or Thumb. The default for both settings is auto, which uses
1668 the current CPSR value for instructions without symbols; previous
1669 versions of GDB behaved as if "set arm fallback-mode arm".
1671 set disable-randomization
1672 show disable-randomization
1673 Standalone programs run with the virtual address space randomization enabled
1674 by default on some platforms. This option keeps the addresses stable across
1675 multiple debugging sessions.
1679 Control whether other threads are stopped or not when some thread hits
1684 Requests that asynchronous execution is enabled in the target, if available.
1685 In this case, it's possible to resume target in the background, and interact
1686 with GDB while the target is running. "show target-async" displays the
1687 current state of asynchronous execution of the target.
1689 set target-wide-charset
1690 show target-wide-charset
1691 The target-wide-charset is the name of the character set that GDB
1692 uses when printing characters whose type is wchar_t.
1694 set tcp auto-retry (on|off)
1696 set tcp connect-timeout
1697 show tcp connect-timeout
1698 These commands allow GDB to retry failed TCP connections to a remote stub
1699 with a specified timeout period; this is useful if the stub is launched
1700 in parallel with GDB but may not be ready to accept connections immediately.
1702 set libthread-db-search-path
1703 show libthread-db-search-path
1704 Control list of directories which GDB will search for appropriate
1707 set schedule-multiple (on|off)
1708 show schedule-multiple
1709 Allow GDB to resume all threads of all processes or only threads of
1710 the current process.
1714 Use more aggressive caching for accesses to the stack. This improves
1715 performance of remote debugging (particularly backtraces) without
1716 affecting correctness.
1718 set interactive-mode (on|off|auto)
1719 show interactive-mode
1720 Control whether GDB runs in interactive mode (on) or not (off).
1721 When in interactive mode, GDB waits for the user to answer all
1722 queries. Otherwise, GDB does not wait and assumes the default
1723 answer. When set to auto (the default), GDB determines which
1724 mode to use based on the stdin settings.
1729 For program forks, this is replaced by the new more generic `info
1730 inferiors' command. To list checkpoints, you can still use the
1731 `info checkpoints' command, which was an alias for the `info forks'
1735 Replaced by the new `inferior' command. To switch between
1736 checkpoints, you can still use the `restart' command, which was an
1737 alias for the `fork' command.
1740 This is removed, since some targets don't have a notion of
1741 processes. To switch between processes, you can still use the
1742 `inferior' command using GDB's own inferior number.
1745 For program forks, this is replaced by the new more generic `kill
1746 inferior' command. To delete a checkpoint, you can still use the
1747 `delete checkpoint' command, which was an alias for the `delete
1751 For program forks, this is replaced by the new more generic `detach
1752 inferior' command. To detach a checkpoint, you can still use the
1753 `detach checkpoint' command, which was an alias for the `detach
1756 * New native configurations
1758 x86/x86_64 Darwin i[34567]86-*-darwin*
1760 x86_64 MinGW x86_64-*-mingw*
1764 Lattice Mico32 lm32-*
1765 x86 DICOS i[34567]86-*-dicos*
1766 x86_64 DICOS x86_64-*-dicos*
1769 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1770 (mingw32ce) debugging.
1776 These commands were actually not implemented on any target.
1778 *** Changes in GDB 6.8
1780 * New native configurations
1782 NetBSD/hppa hppa*-*netbsd*
1783 Xtensa GNU/Linux xtensa*-*-linux*
1787 NetBSD/hppa hppa*-*-netbsd*
1788 Xtensa GNU/Lunux xtensa*-*-linux*
1790 * Change in command line behavior -- corefiles vs. process ids.
1792 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1793 attaching to process NUMBER fails, GDB no longer attempts to open a
1794 core file named NUMBER. Attaching to a program using the -c option
1795 is no longer supported. Instead, use the '-p' or '--pid' options.
1797 * GDB can now be built as a native debugger for debugging Windows x86
1798 (mingw32) Portable Executable (PE) programs.
1800 * Pending breakpoints no longer change their number when their address
1803 * GDB now supports breakpoints with multiple locations,
1804 including breakpoints on C++ constructors, inside C++ templates,
1805 and in inlined functions.
1807 * GDB's ability to debug optimized code has been improved. GDB more
1808 accurately identifies function bodies and lexical blocks that occupy
1809 more than one contiguous range of addresses.
1811 * Target descriptions can now describe registers for PowerPC.
1813 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1814 registers on PowerPC targets.
1816 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1817 targets even when the libthread_db library is not available.
1819 * The GDB remote stub, gdbserver, now supports the new file transfer
1820 commands (remote put, remote get, and remote delete).
1822 * The GDB remote stub, gdbserver, now supports run and attach in
1823 extended-remote mode.
1825 * hppa*64*-*-hpux11* target broken
1826 The debugger is unable to start a program and fails with the following
1827 error: "Error trying to get information about dynamic linker".
1828 The gdb-6.7 release is also affected.
1830 * GDB now supports the --enable-targets= configure option to allow
1831 building a single GDB executable that supports multiple remote
1832 target architectures.
1834 * GDB now supports debugging C and C++ programs which use the
1835 Decimal Floating Point extension. In addition, the PowerPC target
1836 now has a set of pseudo-registers to inspect decimal float values
1837 stored in two consecutive float registers.
1839 * The -break-insert MI command can optionally create pending
1842 * Improved support for debugging Ada
1843 Many improvements to the Ada language support have been made. These
1845 - Better support for Ada2005 interface types
1846 - Improved handling of arrays and slices in general
1847 - Better support for Taft-amendment types
1848 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1850 - Improved command completion in Ada
1853 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1858 set print frame-arguments (all|scalars|none)
1859 show print frame-arguments
1860 The value of this variable can be changed to control which argument
1861 values should be printed by the debugger when displaying a frame.
1866 Transfer files to and from a remote target, and delete remote files.
1873 Transfer files to and from a remote target, and delete remote files.
1875 * New remote packets
1882 Open, close, read, write, and delete files on the remote system.
1885 Attach to an existing process on the remote system, in extended-remote
1889 Run a new process on the remote system, in extended-remote mode.
1891 *** Changes in GDB 6.7
1893 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1894 bfd, libiberty and opcodes, as revealed by static analysis donated by
1895 Coverity, Inc. (http://scan.coverity.com).
1897 * When looking up multiply-defined global symbols, GDB will now prefer the
1898 symbol definition in the current shared library if it was built using the
1899 -Bsymbolic linker option.
1901 * When the Text User Interface (TUI) is not configured, GDB will now
1902 recognize the -tui command-line option and print a message that the TUI
1905 * The GDB remote stub, gdbserver, now has lower overhead for high
1906 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1908 * GDB for MIPS targets now autodetects whether a remote target provides
1909 32-bit or 64-bit register values.
1911 * Support for C++ member pointers has been improved.
1913 * GDB now understands XML target descriptions, which specify the
1914 target's overall architecture. GDB can read a description from
1915 a local file or over the remote serial protocol.
1917 * Vectors of single-byte data use a new integer type which is not
1918 automatically displayed as character or string data.
1920 * The /s format now works with the print command. It displays
1921 arrays of single-byte integers and pointers to single-byte integers
1924 * Target descriptions can now describe target-specific registers,
1925 for architectures which have implemented the support (currently
1926 only ARM, M68K, and MIPS).
1928 * GDB and the GDB remote stub, gdbserver, now support the XScale
1931 * The GDB remote stub, gdbserver, has been updated to support
1932 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1933 has been rewritten to use the standard GDB remote protocol.
1935 * GDB can now step into C++ functions which are called through thunks.
1937 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1939 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1940 layout. It also supports a TextSeg= and DataSeg= response when only
1941 segment base addresses (rather than offsets) are available.
1943 * The /i format now outputs any trailing branch delay slot instructions
1944 immediately following the last instruction within the count specified.
1946 * The GDB remote protocol "T" stop reply packet now supports a
1947 "library" response. Combined with the new "qXfer:libraries:read"
1948 packet, this response allows GDB to debug shared libraries on targets
1949 where the operating system manages the list of loaded libraries (e.g.
1950 Windows and SymbianOS).
1952 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1953 (DLLs) on Windows and Windows CE targets.
1955 * GDB now supports a faster verification that a .debug file matches its binary
1956 according to its build-id signature, if the signature is present.
1962 Enable or disable hardware flow control (RTS/CTS) on the serial port
1963 when debugging using remote targets.
1965 set mem inaccessible-by-default
1966 show mem inaccessible-by-default
1967 If the target supplies a memory map, for instance via the remote
1968 protocol's "qXfer:memory-map:read" packet, setting this variable
1969 prevents GDB from accessing memory outside the memory map. This
1970 is useful for targets with memory mapped registers or which react
1971 badly to accesses of unmapped address space.
1973 set breakpoint auto-hw
1974 show breakpoint auto-hw
1975 If the target supplies a memory map, for instance via the remote
1976 protocol's "qXfer:memory-map:read" packet, setting this variable
1977 lets GDB use hardware breakpoints automatically for memory regions
1978 where it can not use software breakpoints. This covers both the
1979 "break" command and internal breakpoints used for other commands
1980 including "next" and "finish".
1983 catch exception unhandled
1984 Stop the program execution when Ada exceptions are raised.
1987 Stop the program execution when an Ada assertion failed.
1991 Set an alternate system root for target files. This is a more
1992 general version of "set solib-absolute-prefix", which is now
1993 an alias to "set sysroot".
1996 Provide extended SPU facility status information. This set of
1997 commands is available only when debugging the Cell/B.E. SPU
2000 * New native configurations
2002 OpenBSD/sh sh*-*openbsd*
2005 unset tdesc filename
2007 Use the specified local file as an XML target description, and do
2008 not query the target for its built-in description.
2012 OpenBSD/sh sh*-*-openbsd*
2013 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2014 Toshiba Media Processor mep-elf
2016 * New remote packets
2019 Ignore the specified signals; pass them directly to the debugged program
2020 without stopping other threads or reporting them to GDB.
2022 qXfer:features:read:
2023 Read an XML target description from the target, which describes its
2028 Read or write contents of an spufs file on the target system. These
2029 packets are available only on the Cell/B.E. SPU architecture.
2031 qXfer:libraries:read:
2032 Report the loaded shared libraries. Combined with new "T" packet
2033 response, this packet allows GDB to debug shared libraries on
2034 targets where the operating system manages the list of loaded
2035 libraries (e.g. Windows and SymbianOS).
2039 Support for these obsolete configurations has been removed.
2047 i[34567]86-*-lynxos*
2048 i[34567]86-*-netware*
2049 i[34567]86-*-sco3.2v5*
2050 i[34567]86-*-sco3.2v4*
2052 i[34567]86-*-sysv4.2*
2055 i[34567]86-*-unixware2*
2056 i[34567]86-*-unixware*
2065 * Other removed features
2072 Various m68k-only ROM monitors.
2079 Various Renesas ROM monitors and debugging interfaces for SH and
2084 Support for a Macraigor serial interface to on-chip debugging.
2085 GDB does not directly support the newer parallel or USB
2090 A debug information format. The predecessor to DWARF 2 and
2091 DWARF 3, which are still supported.
2093 Support for the HP aCC compiler on HP-UX/PA-RISC
2095 SOM-encapsulated symbolic debugging information, automatic
2096 invocation of pxdb, and the aCC custom C++ ABI. This does not
2097 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2098 with aCC can still be debugged on an assembly level.
2100 MIPS ".pdr" sections
2102 A MIPS-specific format used to describe stack frame layout
2103 in debugging information.
2107 GDB could work with an older version of Guile to debug
2108 the interpreter and Scheme programs running in it.
2110 set mips stack-arg-size
2111 set mips saved-gpreg-size
2113 Use "set mips abi" to control parameter passing for MIPS.
2115 *** Changes in GDB 6.6
2120 Cell Broadband Engine SPU spu-elf
2122 * GDB can now be configured as a cross-debugger targeting native Windows
2123 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2124 running on a Windows system over TCP/IP to debug Windows programs.
2126 * The GDB remote stub, gdbserver, has been updated to support Windows and
2127 Cygwin debugging. Both single-threaded and multi-threaded programs are
2130 * The "set trust-readonly-sections" command works again. This command was
2131 broken in GDB 6.3, 6.4, and 6.5.
2133 * The "load" command now supports writing to flash memory, if the remote
2134 stub provides the required support.
2136 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2137 longer requires symbolic debug information (e.g. DWARF-2).
2142 unset substitute-path
2143 show substitute-path
2144 Manage a list of substitution rules that GDB uses to rewrite the name
2145 of the directories where the sources are located. This can be useful
2146 for instance when the sources were moved to a different location
2147 between compilation and debugging.
2151 Print each CLI command as it is executed. Each command is prefixed with
2152 a number of `+' symbols representing the nesting depth.
2153 The source command now has a `-v' option to enable the same feature.
2157 The ARM Demon monitor support (RDP protocol, "target rdp").
2159 Kernel Object Display, an embedded debugging feature which only worked with
2160 an obsolete version of Cisco IOS.
2162 The 'set download-write-size' and 'show download-write-size' commands.
2164 * New remote packets
2167 Tell a stub about GDB client features, and request remote target features.
2168 The first feature implemented is PacketSize, which allows the target to
2169 specify the size of packets it can handle - to minimize the number of
2170 packets required and improve performance when connected to a remote
2174 Fetch an OS auxilliary vector from the remote stub. This packet is a
2175 more efficient replacement for qPart:auxv:read.
2177 qXfer:memory-map:read:
2178 Fetch a memory map from the remote stub, including information about
2179 RAM, ROM, and flash memory devices.
2184 Erase and program a flash memory device.
2186 * Removed remote packets
2189 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2190 used it, and only gdbserver implemented it.
2192 *** Changes in GDB 6.5
2196 Renesas M32C/M16C m32c-elf
2198 Morpho Technologies ms1 ms1-elf
2202 init-if-undefined Initialize a convenience variable, but
2203 only if it doesn't already have a value.
2205 The following commands are presently only implemented for native GNU/Linux:
2207 checkpoint Save a snapshot of the program state.
2209 restart <n> Return the program state to a
2210 previously saved state.
2212 info checkpoints List currently saved checkpoints.
2214 delete-checkpoint <n> Delete a previously saved checkpoint.
2216 set|show detach-on-fork Tell gdb whether to detach from a newly
2217 forked process, or to keep debugging it.
2219 info forks List forks of the user program that
2220 are available to be debugged.
2222 fork <n> Switch to debugging one of several
2223 forks of the user program that are
2224 available to be debugged.
2226 delete-fork <n> Delete a fork from the list of forks
2227 that are available to be debugged (and
2228 kill the forked process).
2230 detach-fork <n> Delete a fork from the list of forks
2231 that are available to be debugged (and
2232 allow the process to continue).
2236 Morpho Technologies ms2 ms1-elf
2238 * Improved Windows host support
2240 GDB now builds as a cross debugger hosted on i686-mingw32, including
2241 native console support, and remote communications using either
2242 network sockets or serial ports.
2244 * Improved Modula-2 language support
2246 GDB can now print most types in the Modula-2 syntax. This includes:
2247 basic types, set types, record types, enumerated types, range types,
2248 pointer types and ARRAY types. Procedure var parameters are correctly
2249 printed and hexadecimal addresses and character constants are also
2250 written in the Modula-2 syntax. Best results can be obtained by using
2251 GNU Modula-2 together with the -gdwarf-2 command line option.
2255 The ARM rdi-share module.
2257 The Netware NLM debug server.
2259 *** Changes in GDB 6.4
2261 * New native configurations
2263 OpenBSD/arm arm*-*-openbsd*
2264 OpenBSD/mips64 mips64-*-openbsd*
2268 Morpho Technologies ms1 ms1-elf
2270 * New command line options
2272 --batch-silent As for --batch, but totally silent.
2273 --return-child-result The debugger will exist with the same value
2274 the child (debugged) program exited with.
2275 --eval-command COMMAND, -ex COMMAND
2276 Execute a single GDB CLI command. This may be
2277 specified multiple times and in conjunction
2278 with the --command (-x) option.
2280 * Deprecated commands removed
2282 The following commands, that were deprecated in 2000, have been
2286 set|show arm disassembly-flavor set|show arm disassembler
2287 othernames set arm disassembler
2288 set|show remotedebug set|show debug remote
2289 set|show archdebug set|show debug arch
2290 set|show eventdebug set|show debug event
2293 * New BSD user-level threads support
2295 It is now possible to debug programs using the user-level threads
2296 library on OpenBSD and FreeBSD. Currently supported (target)
2299 FreeBSD/amd64 x86_64-*-freebsd*
2300 FreeBSD/i386 i386-*-freebsd*
2301 OpenBSD/i386 i386-*-openbsd*
2303 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2304 are not yet supported.
2306 * New support for Matsushita MN10300 w/sim added
2307 (Work in progress). mn10300-elf.
2309 * REMOVED configurations and files
2311 VxWorks and the XDR protocol *-*-vxworks
2312 Motorola MCORE mcore-*-*
2313 National Semiconductor NS32000 ns32k-*-*
2315 * New "set print array-indexes" command
2317 After turning this setting "on", GDB prints the index of each element
2318 when displaying arrays. The default is "off" to preserve the previous
2321 * VAX floating point support
2323 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2325 * User-defined command support
2327 In addition to using $arg0..$arg9 for argument passing, it is now possible
2328 to use $argc to determine now many arguments have been passed. See the
2329 section on user-defined commands in the user manual for more information.
2331 *** Changes in GDB 6.3:
2333 * New command line option
2335 GDB now accepts -l followed by a number to set the timeout for remote
2338 * GDB works with GCC -feliminate-dwarf2-dups
2340 GDB now supports a more compact representation of DWARF-2 debug
2341 information using DW_FORM_ref_addr references. These are produced
2342 by GCC with the option -feliminate-dwarf2-dups and also by some
2343 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2344 to use -feliminate-dwarf2-dups.
2346 * Internationalization
2348 When supported by the host system, GDB will be built with
2349 internationalization (libintl). The task of marking up the sources is
2350 continued, we're looking forward to our first translation.
2354 Initial support for debugging programs compiled with the GNAT
2355 implementation of the Ada programming language has been integrated
2356 into GDB. In this release, support is limited to expression evaluation.
2358 * New native configurations
2360 GNU/Linux/m32r m32r-*-linux-gnu
2364 GDB's remote protocol now includes support for the 'p' packet. This
2365 packet is used to fetch individual registers from a remote inferior.
2367 * END-OF-LIFE registers[] compatibility module
2369 GDB's internal register infrastructure has been completely rewritten.
2370 The new infrastructure making possible the implementation of key new
2371 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2374 GDB 6.3 will be the last release to include the the registers[]
2375 compatibility module that allowed out-of-date configurations to
2376 continue to work. This change directly impacts the following
2386 powerpc bdm protocol
2388 Unless there is activity to revive these configurations, they will be
2389 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2391 * OBSOLETE configurations and files
2393 Configurations that have been declared obsolete in this release have
2394 been commented out. Unless there is activity to revive these
2395 configurations, the next release of GDB will have their sources
2396 permanently REMOVED.
2405 *** Changes in GDB 6.2.1:
2407 * MIPS `break main; run' gave an heuristic-fence-post warning
2409 When attempting to run even a simple program, a warning about
2410 heuristic-fence-post being hit would be reported. This problem has
2413 * MIPS IRIX 'long double' crashed GDB
2415 When examining a long double variable, GDB would get a segmentation
2416 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2417 IRIX long double values).
2421 A bug in the VAX stack code was causing problems with the "next"
2422 command. This problem has been fixed.
2424 *** Changes in GDB 6.2:
2426 * Fix for ``many threads''
2428 On GNU/Linux systems that use the NPTL threads library, a program
2429 rapidly creating and deleting threads would confuse GDB leading to the
2432 ptrace: No such process.
2433 thread_db_get_info: cannot get thread info: generic error
2435 This problem has been fixed.
2437 * "-async" and "-noasync" options removed.
2439 Support for the broken "-noasync" option has been removed (it caused
2442 * New ``start'' command.
2444 This command runs the program until the begining of the main procedure.
2446 * New BSD Kernel Data Access Library (libkvm) interface
2448 Using ``target kvm'' it is now possible to debug kernel core dumps and
2449 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2450 platforms. Currently supported (native-only) configurations are:
2452 FreeBSD/amd64 x86_64-*-freebsd*
2453 FreeBSD/i386 i?86-*-freebsd*
2454 NetBSD/i386 i?86-*-netbsd*
2455 NetBSD/m68k m68*-*-netbsd*
2456 NetBSD/sparc sparc-*-netbsd*
2457 OpenBSD/amd64 x86_64-*-openbsd*
2458 OpenBSD/i386 i?86-*-openbsd*
2459 OpenBSD/m68k m68*-openbsd*
2460 OpenBSD/sparc sparc-*-openbsd*
2462 * Signal trampoline code overhauled
2464 Many generic problems with GDB's signal handling code have been fixed.
2465 These include: backtraces through non-contiguous stacks; recognition
2466 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2467 call; backtrace through a signal trampoline; step into and out of
2468 signal handlers; and single-stepping in the signal trampoline.
2470 Please note that kernel bugs are a limiting factor here. These
2471 features have been shown to work on an s390 GNU/Linux system that
2472 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2474 * Cygwin support for DWARF 2 added.
2476 * New native configurations
2478 GNU/Linux/hppa hppa*-*-linux*
2479 OpenBSD/hppa hppa*-*-openbsd*
2480 OpenBSD/m68k m68*-*-openbsd*
2481 OpenBSD/m88k m88*-*-openbsd*
2482 OpenBSD/powerpc powerpc-*-openbsd*
2483 NetBSD/vax vax-*-netbsd*
2484 OpenBSD/vax vax-*-openbsd*
2486 * END-OF-LIFE frame compatibility module
2488 GDB's internal frame infrastructure has been completely rewritten.
2489 The new infrastructure making it possible to support key new features
2490 including DWARF 2 Call Frame Information. To aid in the task of
2491 migrating old configurations to this new infrastructure, a
2492 compatibility module, that allowed old configurations to continue to
2493 work, was also included.
2495 GDB 6.2 will be the last release to include this frame compatibility
2496 module. This change directly impacts the following configurations:
2506 Unless there is activity to revive these configurations, they will be
2507 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2509 * REMOVED configurations and files
2511 Sun 3, running SunOS 3 m68*-*-sunos3*
2512 Sun 3, running SunOS 4 m68*-*-sunos4*
2513 Sun 2, running SunOS 3 m68000-*-sunos3*
2514 Sun 2, running SunOS 4 m68000-*-sunos4*
2515 Motorola 680x0 running LynxOS m68*-*-lynxos*
2516 AT&T 3b1/Unix pc m68*-att-*
2517 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2518 decstation mips-dec-* mips-little-*
2519 riscos mips-*-riscos* mips-*-sysv*
2520 sonymips mips-sony-*
2521 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2523 *** Changes in GDB 6.1.1:
2525 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2527 The TUI (Text-mode User Interface) is now built as part of a default
2528 GDB configuration. It is enabled by either selecting the TUI with the
2529 command line option "-i=tui" or by running the separate "gdbtui"
2530 program. For more information on the TUI, see the manual "Debugging
2533 * Pending breakpoint support (also included in GDB 6.1)
2535 Support has been added to allow you to specify breakpoints in shared
2536 libraries that have not yet been loaded. If a breakpoint location
2537 cannot be found, and the "breakpoint pending" option is set to auto,
2538 GDB queries you if you wish to make the breakpoint pending on a future
2539 shared-library load. If and when GDB resolves the breakpoint symbol,
2540 the pending breakpoint is removed as one or more regular breakpoints
2543 Pending breakpoints are very useful for GCJ Java debugging.
2545 * Fixed ISO-C build problems
2547 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2548 non ISO-C code that stopped them being built using a more strict ISO-C
2549 compiler (e.g., IBM's C compiler).
2551 * Fixed build problem on IRIX 5
2553 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2554 wasn't able to compile compile on an IRIX 5 system.
2556 * Added execute permission to gdb/gdbserver/configure
2558 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2559 permission. This bug would cause configure to fail on a number of
2560 systems (Solaris, IRIX). Ref: server/519.
2562 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2564 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2565 has been updated to use constant array sizes.
2567 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2569 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2570 its generated DWARF Call Frame Info. This encoding was causing GDB to
2571 panic, that panic has been fixed. Ref: gdb/1628.
2573 * Fixed a problem when examining parameters in shared library code.
2575 When examining parameters in optimized shared library code generated
2576 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2577 not available''. GDB now correctly displays the variable's value.
2579 *** Changes in GDB 6.1:
2581 * Removed --with-mmalloc
2583 Support for the mmalloc memory manager has been removed, as it
2584 conflicted with the internal gdb byte cache.
2586 * Changes in AMD64 configurations
2588 The AMD64 target now includes the %cs and %ss registers. As a result
2589 the AMD64 remote protocol has changed; this affects the floating-point
2590 and SSE registers. If you rely on those registers for your debugging,
2591 you should upgrade gdbserver on the remote side.
2593 * Revised SPARC target
2595 The SPARC target has been completely revised, incorporating the
2596 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2597 support for LynxOS and SunOS 4 has been dropped. Calling functions
2598 from within GDB on operating systems with a non-executable stack
2599 (Solaris, OpenBSD) now works.
2603 GDB has a new C++ demangler which does a better job on the mangled
2604 names generated by current versions of g++. It also runs faster, so
2605 with this and other changes gdb should now start faster on large C++
2608 * DWARF 2 Location Expressions
2610 GDB support for location expressions has been extended to support function
2611 arguments and frame bases. Older versions of GDB could crash when they
2614 * C++ nested types and namespaces
2616 GDB's support for nested types and namespaces in C++ has been
2617 improved, especially if you use the DWARF 2 debugging format. (This
2618 is the default for recent versions of GCC on most platforms.)
2619 Specifically, if you have a class "Inner" defined within a class or
2620 namespace "Outer", then GDB realizes that the class's name is
2621 "Outer::Inner", not simply "Inner". This should greatly reduce the
2622 frequency of complaints about not finding RTTI symbols. In addition,
2623 if you are stopped at inside of a function defined within a namespace,
2624 GDB modifies its name lookup accordingly.
2626 * New native configurations
2628 NetBSD/amd64 x86_64-*-netbsd*
2629 OpenBSD/amd64 x86_64-*-openbsd*
2630 OpenBSD/alpha alpha*-*-openbsd*
2631 OpenBSD/sparc sparc-*-openbsd*
2632 OpenBSD/sparc64 sparc64-*-openbsd*
2634 * New debugging protocols
2636 M32R with SDI protocol m32r-*-elf*
2638 * "set prompt-escape-char" command deleted.
2640 The command "set prompt-escape-char" has been deleted. This command,
2641 and its very obscure effet on GDB's prompt, was never documented,
2642 tested, nor mentioned in the NEWS file.
2644 * OBSOLETE configurations and files
2646 Configurations that have been declared obsolete in this release have
2647 been commented out. Unless there is activity to revive these
2648 configurations, the next release of GDB will have their sources
2649 permanently REMOVED.
2651 Sun 3, running SunOS 3 m68*-*-sunos3*
2652 Sun 3, running SunOS 4 m68*-*-sunos4*
2653 Sun 2, running SunOS 3 m68000-*-sunos3*
2654 Sun 2, running SunOS 4 m68000-*-sunos4*
2655 Motorola 680x0 running LynxOS m68*-*-lynxos*
2656 AT&T 3b1/Unix pc m68*-att-*
2657 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2658 decstation mips-dec-* mips-little-*
2659 riscos mips-*-riscos* mips-*-sysv*
2660 sonymips mips-sony-*
2661 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2663 * REMOVED configurations and files
2665 SGI Irix-4.x mips-sgi-irix4 or iris4
2666 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2667 Z8000 simulator z8k-zilog-none or z8ksim
2668 Matsushita MN10200 w/simulator mn10200-*-*
2669 H8/500 simulator h8500-hitachi-hms or h8500hms
2670 HP/PA running BSD hppa*-*-bsd*
2671 HP/PA running OSF/1 hppa*-*-osf*
2672 HP/PA Pro target hppa*-*-pro*
2673 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2674 386BSD i[3456]86-*-bsd*
2675 Sequent family i[3456]86-sequent-sysv4*
2676 i[3456]86-sequent-sysv*
2677 i[3456]86-sequent-bsd*
2678 SPARC running LynxOS sparc-*-lynxos*
2679 SPARC running SunOS 4 sparc-*-sunos4*
2680 Tsqware Sparclet sparclet-*-*
2681 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2683 *** Changes in GDB 6.0:
2687 Support for debugging the Objective-C programming language has been
2688 integrated into GDB.
2690 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2692 DWARF 2's Call Frame Information makes available compiler generated
2693 information that more exactly describes the program's run-time stack.
2694 By using this information, GDB is able to provide more robust stack
2697 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2698 have been updated to use a new backtrace mechanism which includes
2699 DWARF 2 CFI support.
2703 GDB's remote protocol has been extended to include support for hosted
2704 file I/O (where the remote target uses GDB's file system). See GDB's
2705 remote protocol documentation for details.
2707 * All targets using the new architecture framework.
2709 All of GDB's targets have been updated to use the new internal
2710 architecture framework. The way is now open for future GDB releases
2711 to include cross-architecture native debugging support (i386 on amd64,
2714 * GNU/Linux's Thread Local Storage (TLS)
2716 GDB now includes support for for the GNU/Linux implementation of
2717 per-thread variables.
2719 * GNU/Linux's Native POSIX Thread Library (NPTL)
2721 GDB's thread code has been updated to work with either the new
2722 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2724 * Separate debug info.
2726 GDB, in conjunction with BINUTILS, now supports a mechanism for
2727 automatically loading debug information from a separate file. Instead
2728 of shipping full debug and non-debug versions of system libraries,
2729 system integrators can now instead ship just the stripped libraries
2730 and optional debug files.
2732 * DWARF 2 Location Expressions
2734 DWARF 2 Location Expressions allow the compiler to more completely
2735 describe the location of variables (even in optimized code) to the
2738 GDB now includes preliminary support for location expressions (support
2739 for DW_OP_piece is still missing).
2743 A number of long standing bugs that caused GDB to die while starting a
2744 Java application have been fixed. GDB's Java support is now
2745 considered "useable".
2747 * GNU/Linux support for fork, vfork, and exec.
2749 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2750 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2753 * GDB supports logging output to a file
2755 There are two new commands, "set logging" and "show logging", which can be
2756 used to capture GDB's output to a file.
2758 * The meaning of "detach" has changed for gdbserver
2760 The "detach" command will now resume the application, as documented. To
2761 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2764 * d10v, m68hc11 `regs' command deprecated
2766 The `info registers' command has been updated so that it displays the
2767 registers using a format identical to the old `regs' command.
2771 A new command, "maint set profile on/off", has been added. This command can
2772 be used to enable or disable profiling while running GDB, to profile a
2773 session or a set of commands. In addition there is a new configure switch,
2774 "--enable-profiling", which will cause GDB to be compiled with profiling
2775 data, for more informative profiling results.
2777 * Default MI syntax changed to "mi2".
2779 The default MI (machine interface) syntax, enabled by the command line
2780 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2781 "mi1", can be enabled by specifying the option "-i=mi1".
2783 Support for the original "mi0" syntax (included in GDB 5.0) has been
2786 Fix for gdb/192: removed extraneous space when displaying frame level.
2787 Fix for gdb/672: update changelist is now output in mi list format.
2788 Fix for gdb/702: a -var-assign that updates the value now shows up
2789 in a subsequent -var-update.
2791 * New native configurations.
2793 FreeBSD/amd64 x86_64-*-freebsd*
2795 * Multi-arched targets.
2797 HP/PA HPUX11 hppa*-*-hpux*
2798 Renesas M32R/D w/simulator m32r-*-elf*
2800 * OBSOLETE configurations and files
2802 Configurations that have been declared obsolete in this release have
2803 been commented out. Unless there is activity to revive these
2804 configurations, the next release of GDB will have their sources
2805 permanently REMOVED.
2807 Z8000 simulator z8k-zilog-none or z8ksim
2808 Matsushita MN10200 w/simulator mn10200-*-*
2809 H8/500 simulator h8500-hitachi-hms or h8500hms
2810 HP/PA running BSD hppa*-*-bsd*
2811 HP/PA running OSF/1 hppa*-*-osf*
2812 HP/PA Pro target hppa*-*-pro*
2813 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2814 Sequent family i[3456]86-sequent-sysv4*
2815 i[3456]86-sequent-sysv*
2816 i[3456]86-sequent-bsd*
2817 Tsqware Sparclet sparclet-*-*
2818 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2820 * REMOVED configurations and files
2823 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2824 IBM AIX PS/2 i[3456]86-*-aix
2825 i386 running Mach 3.0 i[3456]86-*-mach3*
2826 i386 running Mach i[3456]86-*-mach*
2827 i386 running OSF/1 i[3456]86-*osf1mk*
2828 HP/Apollo 68k Family m68*-apollo*-sysv*,
2830 m68*-hp-bsd*, m68*-hp-hpux*
2831 Argonaut Risc Chip (ARC) arc-*-*
2832 Mitsubishi D30V d30v-*-*
2833 Fujitsu FR30 fr30-*-elf*
2834 OS/9000 i[34]86-*-os9k
2835 I960 with MON960 i960-*-coff
2837 * MIPS $fp behavior changed
2839 The convenience variable $fp, for the MIPS, now consistently returns
2840 the address of the current frame's base. Previously, depending on the
2841 context, $fp could refer to either $sp or the current frame's base
2842 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2843 The GNU Source-Level Debugger''.
2845 *** Changes in GDB 5.3:
2847 * GNU/Linux shared library multi-threaded performance improved.
2849 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2850 `/proc', in preference to `ptrace' for memory reads. This may result
2851 in an improvement in the start-up time of multi-threaded, shared
2852 library applications when run under GDB. One GDB user writes: ``loads
2853 shared libs like mad''.
2855 * ``gdbserver'' now supports multi-threaded applications on some targets
2857 Support for debugging multi-threaded applications which use
2858 the GNU/Linux LinuxThreads package has been added for
2859 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2860 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2862 * GDB now supports C/C++ preprocessor macros.
2864 GDB now expands preprocessor macro invocations in C/C++ expressions,
2865 and provides various commands for showing macro definitions and how
2868 The new command `macro expand EXPRESSION' expands any macro
2869 invocations in expression, and shows the result.
2871 The new command `show macro MACRO-NAME' shows the definition of the
2872 macro named MACRO-NAME, and where it was defined.
2874 Most compilers don't include information about macros in the debugging
2875 information by default. In GCC 3.1, for example, you need to compile
2876 your program with the options `-gdwarf-2 -g3'. If the macro
2877 information is present in the executable, GDB will read it.
2879 * Multi-arched targets.
2881 DEC Alpha (partial) alpha*-*-*
2882 DEC VAX (partial) vax-*-*
2884 National Semiconductor NS32000 (partial) ns32k-*-*
2885 Motorola 68000 (partial) m68k-*-*
2886 Motorola MCORE mcore-*-*
2890 Fujitsu FRV architecture added by Red Hat frv*-*-*
2893 * New native configurations
2895 Alpha NetBSD alpha*-*-netbsd*
2896 SH NetBSD sh*-*-netbsdelf*
2897 MIPS NetBSD mips*-*-netbsd*
2898 UltraSPARC NetBSD sparc64-*-netbsd*
2900 * OBSOLETE configurations and files
2902 Configurations that have been declared obsolete in this release have
2903 been commented out. Unless there is activity to revive these
2904 configurations, the next release of GDB will have their sources
2905 permanently REMOVED.
2907 Mitsubishi D30V d30v-*-*
2908 OS/9000 i[34]86-*-os9k
2909 IBM AIX PS/2 i[3456]86-*-aix
2910 Fujitsu FR30 fr30-*-elf*
2911 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2912 Argonaut Risc Chip (ARC) arc-*-*
2913 i386 running Mach 3.0 i[3456]86-*-mach3*
2914 i386 running Mach i[3456]86-*-mach*
2915 i386 running OSF/1 i[3456]86-*osf1mk*
2916 HP/Apollo 68k Family m68*-apollo*-sysv*,
2918 m68*-hp-bsd*, m68*-hp-hpux*
2919 I960 with MON960 i960-*-coff
2921 * OBSOLETE languages
2923 CHILL, a Pascal like language used by telecommunications companies.
2925 * REMOVED configurations and files
2927 AMD 29k family via UDI a29k-amd-udi, udi29k
2928 A29K VxWorks a29k-*-vxworks
2929 AMD 29000 embedded, using EBMON a29k-none-none
2930 AMD 29000 embedded with COFF a29k-none-coff
2931 AMD 29000 embedded with a.out a29k-none-aout
2933 testsuite/gdb.hp/gdb.threads-hp/ directory
2935 * New command "set max-user-call-depth <nnn>"
2937 This command allows the user to limit the call depth of user-defined
2938 commands. The default is 1024.
2940 * Changes in FreeBSD/i386 native debugging.
2942 Support for the "generate-core-file" has been added.
2944 * New commands "dump", "append", and "restore".
2946 These commands allow data to be copied from target memory
2947 to a bfd-format or binary file (dump and append), and back
2948 from a file into memory (restore).
2950 * Improved "next/step" support on multi-processor Alpha Tru64.
2952 The previous single-step mechanism could cause unpredictable problems,
2953 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2954 of a software single-step mechanism prevents this.
2956 *** Changes in GDB 5.2.1:
2964 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2965 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2966 Fix, by Joel Brobecker imported from mainline.
2968 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2969 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2970 Fix, by Fred Fish, imported from mainline.
2972 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2973 Surprisingly enough, it works now.
2974 By Michal Ludvig, imported from mainline.
2976 i386 hardware watchpoint support:
2977 avoid misses on second run for some targets.
2978 By Pierre Muller, imported from mainline.
2980 *** Changes in GDB 5.2:
2982 * New command "set trust-readonly-sections on[off]".
2984 This command is a hint that tells gdb that read-only sections
2985 really are read-only (ie. that their contents will not change).
2986 In this mode, gdb will go to the object file rather than the
2987 target to read memory from read-only sections (such as ".text").
2988 This can be a significant performance improvement on some
2989 (notably embedded) targets.
2991 * New command "generate-core-file" (or "gcore").
2993 This new gdb command allows the user to drop a core file of the child
2994 process state at any time. So far it's been implemented only for
2995 GNU/Linux and Solaris, but should be relatively easily ported to other
2996 hosts. Argument is core file name (defaults to core.<pid>).
2998 * New command line option
3000 GDB now accepts --pid or -p followed by a process id.
3002 * Change in command line behavior -- corefiles vs. process ids.
3004 There is a subtle behavior in the way in which GDB handles
3005 command line arguments. The first non-flag argument is always
3006 a program to debug, but the second non-flag argument may either
3007 be a corefile or a process id. Previously, GDB would attempt to
3008 open the second argument as a corefile, and if that failed, would
3009 issue a superfluous error message and then attempt to attach it as
3010 a process. Now, if the second argument begins with a non-digit,
3011 it will be treated as a corefile. If it begins with a digit,
3012 GDB will attempt to attach it as a process, and if no such process
3013 is found, will then attempt to open it as a corefile.
3015 * Changes in ARM configurations.
3017 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3018 configuration is fully multi-arch.
3020 * New native configurations
3022 ARM NetBSD arm*-*-netbsd*
3023 x86 OpenBSD i[3456]86-*-openbsd*
3024 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3025 Sparc64 running FreeBSD sparc64-*-freebsd*
3029 Sanyo XStormy16 xstormy16-elf
3031 * OBSOLETE configurations and files
3033 Configurations that have been declared obsolete in this release have
3034 been commented out. Unless there is activity to revive these
3035 configurations, the next release of GDB will have their sources
3036 permanently REMOVED.
3038 AMD 29k family via UDI a29k-amd-udi, udi29k
3039 A29K VxWorks a29k-*-vxworks
3040 AMD 29000 embedded, using EBMON a29k-none-none
3041 AMD 29000 embedded with COFF a29k-none-coff
3042 AMD 29000 embedded with a.out a29k-none-aout
3044 testsuite/gdb.hp/gdb.threads-hp/ directory
3046 * REMOVED configurations and files
3048 TI TMS320C80 tic80-*-*
3050 PowerPC Solaris powerpcle-*-solaris*
3051 PowerPC Windows NT powerpcle-*-cygwin32
3052 PowerPC Netware powerpc-*-netware*
3053 Harris/CXUX m88k m88*-harris-cxux*
3054 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3055 ns32k-utek-sysv* ns32k-utek-*
3056 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3057 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3058 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3059 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3060 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3062 * Changes to command line processing
3064 The new `--args' feature can be used to specify command-line arguments
3065 for the inferior from gdb's command line.
3067 * Changes to key bindings
3069 There is a new `operate-and-get-next' function bound to `C-o'.
3071 *** Changes in GDB 5.1.1
3073 Fix compile problem on DJGPP.
3075 Fix a problem with floating-point registers on the i386 being
3078 Fix to stop GDB crashing on .debug_str debug info.
3080 Numerous documentation fixes.
3082 Numerous testsuite fixes.
3084 *** Changes in GDB 5.1:
3086 * New native configurations
3088 Alpha FreeBSD alpha*-*-freebsd*
3089 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3090 MIPS GNU/Linux mips*-*-linux*
3091 MIPS SGI Irix 6.x mips*-sgi-irix6*
3092 ia64 AIX ia64-*-aix*
3093 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3097 Motorola 68HC11 and 68HC12 m68hc11-elf
3099 UltraSparc running GNU/Linux sparc64-*-linux*
3101 * OBSOLETE configurations and files
3103 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3104 Harris/CXUX m88k m88*-harris-cxux*
3105 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3106 ns32k-utek-sysv* ns32k-utek-*
3107 TI TMS320C80 tic80-*-*
3109 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3110 PowerPC Solaris powerpcle-*-solaris*
3111 PowerPC Windows NT powerpcle-*-cygwin32
3112 PowerPC Netware powerpc-*-netware*
3113 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3114 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3115 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3116 Apple Macintosh (MPW) host N/A
3118 stuff.c (Program to stuff files into a specially prepared space in kdb)
3119 kdb-start.c (Main loop for the standalone kernel debugger)
3121 Configurations that have been declared obsolete in this release have
3122 been commented out. Unless there is activity to revive these
3123 configurations, the next release of GDB will have their sources
3124 permanently REMOVED.
3126 * REMOVED configurations and files
3128 Altos 3068 m68*-altos-*
3129 Convex c1-*-*, c2-*-*
3131 ARM RISCix arm-*-* (as host)
3135 * GDB has been converted to ISO C.
3137 GDB's source code has been converted to ISO C. In particular, the
3138 sources are fully protoized, and rely on standard headers being
3143 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3145 * The MI enabled by default.
3147 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3148 revised and enabled by default. Packages which use GDB as a debugging
3149 engine behind a UI or another front end are encouraged to switch to
3150 using the GDB/MI interface, instead of the old annotations interface
3151 which is now deprecated.
3153 * Support for debugging Pascal programs.
3155 GDB now includes support for debugging Pascal programs. The following
3156 main features are supported:
3158 - Pascal-specific data types such as sets;
3160 - automatic recognition of Pascal sources based on file-name
3163 - Pascal-style display of data types, variables, and functions;
3165 - a Pascal expression parser.
3167 However, some important features are not yet supported.
3169 - Pascal string operations are not supported at all;
3171 - there are some problems with boolean types;
3173 - Pascal type hexadecimal constants are not supported
3174 because they conflict with the internal variables format;
3176 - support for Pascal objects and classes is not full yet;
3178 - unlike Pascal, GDB is case-sensitive for symbol names.
3180 * Changes in completion.
3182 Commands such as `shell', `run' and `set args', which pass arguments
3183 to inferior programs, now complete on file names, similar to what
3184 users expect at the shell prompt.
3186 Commands which accept locations, such as `disassemble', `print',
3187 `breakpoint', `until', etc. now complete on filenames as well as
3188 program symbols. Thus, if you type "break foob TAB", and the source
3189 files linked into the programs include `foobar.c', that file name will
3190 be one of the candidates for completion. However, file names are not
3191 considered for completion after you typed a colon that delimits a file
3192 name from a name of a function in that file, as in "break foo.c:bar".
3194 `set demangle-style' completes on available demangling styles.
3196 * New platform-independent commands:
3198 It is now possible to define a post-hook for a command as well as a
3199 hook that runs before the command. For more details, see the
3200 documentation of `hookpost' in the GDB manual.
3202 * Changes in GNU/Linux native debugging.
3204 Support for debugging multi-threaded programs has been completely
3205 revised for all platforms except m68k and sparc. You can now debug as
3206 many threads as your system allows you to have.
3208 Attach/detach is supported for multi-threaded programs.
3210 Support for SSE registers was added for x86. This doesn't work for
3211 multi-threaded programs though.
3213 * Changes in MIPS configurations.
3215 Multi-arch support is enabled for all MIPS configurations.
3217 GDB can now be built as native debugger on SGI Irix 6.x systems for
3218 debugging n32 executables. (Debugging 64-bit executables is not yet
3221 * Unified support for hardware watchpoints in all x86 configurations.
3223 Most (if not all) native x86 configurations support hardware-assisted
3224 breakpoints and watchpoints in a unified manner. This support
3225 implements debug register sharing between watchpoints, which allows to
3226 put a virtually infinite number of watchpoints on the same address,
3227 and also supports watching regions up to 16 bytes with several debug
3230 The new maintenance command `maintenance show-debug-regs' toggles
3231 debugging print-outs in functions that insert, remove, and test
3232 watchpoints and hardware breakpoints.
3234 * Changes in the DJGPP native configuration.
3236 New command ``info dos sysinfo'' displays assorted information about
3237 the CPU, OS, memory, and DPMI server.
3239 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3240 display information about segment descriptors stored in GDT, LDT, and
3243 New commands ``info dos pde'' and ``info dos pte'' display entries
3244 from Page Directory and Page Tables (for now works with CWSDPMI only).
3245 New command ``info dos address-pte'' displays the Page Table entry for
3246 a given linear address.
3248 GDB can now pass command lines longer than 126 characters to the
3249 program being debugged (requires an update to the libdbg.a library
3250 which is part of the DJGPP development kit).
3252 DWARF2 debug info is now supported.
3254 It is now possible to `step' and `next' through calls to `longjmp'.
3256 * Changes in documentation.
3258 All GDB documentation was converted to GFDL, the GNU Free
3259 Documentation License.
3261 Tracepoints-related commands are now fully documented in the GDB
3264 TUI, the Text-mode User Interface, is now documented in the manual.
3266 Tracepoints-related commands are now fully documented in the GDB
3269 The "GDB Internals" manual now has an index. It also includes
3270 documentation of `ui_out' functions, GDB coding standards, x86
3271 hardware watchpoints, and memory region attributes.
3273 * GDB's version number moved to ``version.in''
3275 The Makefile variable VERSION has been replaced by the file
3276 ``version.in''. People creating GDB distributions should update the
3277 contents of this file.
3281 GUD support is now a standard part of the EMACS distribution.
3283 *** Changes in GDB 5.0:
3285 * Improved support for debugging FP programs on x86 targets
3287 Unified and much-improved support for debugging floating-point
3288 programs on all x86 targets. In particular, ``info float'' now
3289 displays the FP registers in the same format on all x86 targets, with
3290 greater level of detail.
3292 * Improvements and bugfixes in hardware-assisted watchpoints
3294 It is now possible to watch array elements, struct members, and
3295 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3296 on x86 targets no longer erroneously trigger when the address is
3299 * Improvements in the native DJGPP version of GDB
3301 The distribution now includes all the scripts and auxiliary files
3302 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3303 machines ``out of the box''.
3305 The DJGPP version can now debug programs that use signals. It is
3306 possible to catch signals that happened in the debuggee, deliver
3307 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3308 would kill the program being debugged.) Programs that hook hardware
3309 interrupts (keyboard, timer, etc.) can also be debugged.
3311 It is now possible to debug DJGPP programs that redirect their
3312 standard handles or switch them to raw (as opposed to cooked) mode, or
3313 even close them. The command ``run < foo > bar'' works as expected,
3314 and ``info terminal'' reports useful information about the debuggee's
3315 terminal, including raw/cooked mode, redirection, etc.
3317 The DJGPP version now uses termios functions for console I/O, which
3318 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3321 DOS-style file names with drive letters are now fully supported by
3324 It is now possible to debug DJGPP programs that switch their working
3325 directory. It is also possible to rerun the debuggee any number of
3326 times without restarting GDB; thus, you can use the same setup,
3327 breakpoints, etc. for many debugging sessions.
3329 * New native configurations
3331 ARM GNU/Linux arm*-*-linux*
3332 PowerPC GNU/Linux powerpc-*-linux*
3336 Motorola MCore mcore-*-*
3337 x86 VxWorks i[3456]86-*-vxworks*
3338 PowerPC VxWorks powerpc-*-vxworks*
3339 TI TMS320C80 tic80-*-*
3341 * OBSOLETE configurations
3343 Altos 3068 m68*-altos-*
3344 Convex c1-*-*, c2-*-*
3346 ARM RISCix arm-*-* (as host)
3349 Configurations that have been declared obsolete will be commented out,
3350 but the code will be left in place. If there is no activity to revive
3351 these configurations before the next release of GDB, the sources will
3352 be permanently REMOVED.
3354 * Gould support removed
3356 Support for the Gould PowerNode and NP1 has been removed.
3358 * New features for SVR4
3360 On SVR4 native platforms (such as Solaris), if you attach to a process
3361 without first loading a symbol file, GDB will now attempt to locate and
3362 load symbols from the running process's executable file.
3364 * Many C++ enhancements
3366 C++ support has been greatly improved. Overload resolution now works properly
3367 in almost all cases. RTTI support is on the way.
3369 * Remote targets can connect to a sub-program
3371 A popen(3) style serial-device has been added. This device starts a
3372 sub-process (such as a stand-alone simulator) and then communicates
3373 with that. The sub-program to run is specified using the syntax
3374 ``|<program> <args>'' vis:
3376 (gdb) set remotedebug 1
3377 (gdb) target extended-remote |mn10300-elf-sim program-args
3379 * MIPS 64 remote protocol
3381 A long standing bug in the mips64 remote protocol where by GDB
3382 expected certain 32 bit registers (ex SR) to be transfered as 32
3383 instead of 64 bits has been fixed.
3385 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3386 added to provide backward compatibility with older versions of GDB.
3388 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3390 The command ``set remotebinarydownload'' command has been replaced by
3391 ``set remote X-packet''. Other commands in ``set remote'' family
3392 include ``set remote P-packet''.
3394 * Breakpoint commands accept ranges.
3396 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3397 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3398 ``tracepoint passcount'' also accepts a range of tracepoints.
3400 * ``apropos'' command added.
3402 The ``apropos'' command searches through command names and
3403 documentation strings, printing out matches, making it much easier to
3404 try to find a command that does what you are looking for.
3408 A new machine oriented interface (MI) has been added to GDB. This
3409 interface is designed for debug environments running GDB as a separate
3410 process. This is part of the long term libGDB project. See the
3411 "GDB/MI" chapter of the GDB manual for further information. It can be
3412 enabled by configuring with:
3414 .../configure --enable-gdbmi
3416 *** Changes in GDB-4.18:
3418 * New native configurations
3420 HP-UX 10.20 hppa*-*-hpux10.20
3421 HP-UX 11.x hppa*-*-hpux11.0*
3422 M68K GNU/Linux m68*-*-linux*
3426 Fujitsu FR30 fr30-*-elf*
3427 Intel StrongARM strongarm-*-*
3428 Mitsubishi D30V d30v-*-*
3430 * OBSOLETE configurations
3432 Gould PowerNode, NP1 np1-*-*, pn-*-*
3434 Configurations that have been declared obsolete will be commented out,
3435 but the code will be left in place. If there is no activity to revive
3436 these configurations before the next release of GDB, the sources will
3437 be permanently REMOVED.
3441 As a compatibility experiment, GDB's source files buildsym.h and
3442 buildsym.c have been converted to pure standard C, no longer
3443 containing any K&R compatibility code. We believe that all systems in
3444 use today either come with a standard C compiler, or have a GCC port
3445 available. If this is not true, please report the affected
3446 configuration to bug-gdb@gnu.org immediately. See the README file for
3447 information about getting a standard C compiler if you don't have one
3452 GDB now uses readline 2.2.
3454 * set extension-language
3456 You can now control the mapping between filename extensions and source
3457 languages by using the `set extension-language' command. For instance,
3458 you can ask GDB to treat .c files as C++ by saying
3459 set extension-language .c c++
3460 The command `info extensions' lists all of the recognized extensions
3461 and their associated languages.
3463 * Setting processor type for PowerPC and RS/6000
3465 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3466 you can use the `set processor' command to specify what variant of the
3467 PowerPC family you are debugging. The command
3471 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3472 following PowerPC and RS6000 variants:
3474 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3475 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3477 403GC IBM PowerPC 403GC
3478 505 Motorola PowerPC 505
3479 860 Motorola PowerPC 860 or 850
3480 601 Motorola PowerPC 601
3481 602 Motorola PowerPC 602
3482 603 Motorola/IBM PowerPC 603 or 603e
3483 604 Motorola PowerPC 604 or 604e
3484 750 Motorola/IBM PowerPC 750 or 750
3486 At the moment, this command just tells GDB what to name the
3487 special-purpose processor registers. Since almost all the affected
3488 registers are inaccessible to user-level programs, this command is
3489 only useful for remote debugging in its present form.
3493 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3494 more extensive support for HP-UX. Added features include shared
3495 library support, kernel threads and hardware watchpoints for 11.00,
3496 support for HP's ANSI C and C++ compilers, and a compatibility mode
3497 for xdb and dbx commands.
3501 HP's donation includes the new concept of catchpoints, which is a
3502 generalization of the old catch command. On HP-UX, it is now possible
3503 to catch exec, fork, and vfork, as well as library loading.
3505 This means that the existing catch command has changed; its first
3506 argument now specifies the type of catch to be set up. See the
3507 output of "help catch" for a list of catchpoint types.
3509 * Debugging across forks
3511 On HP-UX, you can choose which process to debug when a fork() happens
3516 HP has donated a curses-based terminal user interface (TUI). To get
3517 it, build with --enable-tui. Although this can be enabled for any
3518 configuration, at present it only works for native HP debugging.
3520 * GDB remote protocol additions
3522 A new protocol packet 'X' that writes binary data is now available.
3523 Default behavior is to try 'X', then drop back to 'M' if the stub
3524 fails to respond. The settable variable `remotebinarydownload'
3525 allows explicit control over the use of 'X'.
3527 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3528 full 64-bit address. The command
3530 set remoteaddresssize 32
3532 can be used to revert to the old behaviour. For existing remote stubs
3533 the change should not be noticed, as the additional address information
3536 In order to assist in debugging stubs, you may use the maintenance
3537 command `packet' to send any text string to the stub. For instance,
3539 maint packet heythere
3541 sends the packet "$heythere#<checksum>". Note that it is very easy to
3542 disrupt a debugging session by sending the wrong packet at the wrong
3545 The compare-sections command allows you to compare section data on the
3546 target to what is in the executable file without uploading or
3547 downloading, by comparing CRC checksums.
3549 * Tracing can collect general expressions
3551 You may now collect general expressions at tracepoints. This requires
3552 further additions to the target-side stub; see tracepoint.c and
3553 doc/agentexpr.texi for further details.
3555 * mask-address variable for Mips
3557 For Mips targets, you may control the zeroing of the upper 32 bits of
3558 a 64-bit address by entering `set mask-address on'. This is mainly
3559 of interest to users of embedded R4xxx and R5xxx processors.
3561 * Higher serial baud rates
3563 GDB's serial code now allows you to specify baud rates 57600, 115200,
3564 230400, and 460800 baud. (Note that your host system may not be able
3565 to achieve all of these rates.)
3569 The i960 configuration now includes an initial implementation of a
3570 builtin simulator, contributed by Jim Wilson.
3573 *** Changes in GDB-4.17:
3575 * New native configurations
3577 Alpha GNU/Linux alpha*-*-linux*
3578 Unixware 2.x i[3456]86-unixware2*
3579 Irix 6.x mips*-sgi-irix6*
3580 PowerPC GNU/Linux powerpc-*-linux*
3581 PowerPC Solaris powerpcle-*-solaris*
3582 Sparc GNU/Linux sparc-*-linux*
3583 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3587 Argonaut Risc Chip (ARC) arc-*-*
3588 Hitachi H8/300S h8300*-*-*
3589 Matsushita MN10200 w/simulator mn10200-*-*
3590 Matsushita MN10300 w/simulator mn10300-*-*
3591 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3592 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3593 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3594 Mitsubishi D10V w/simulator d10v-*-*
3595 Mitsubishi M32R/D w/simulator m32r-*-elf*
3596 Tsqware Sparclet sparclet-*-*
3597 NEC V850 w/simulator v850-*-*
3599 * New debugging protocols
3601 ARM with RDI protocol arm*-*-*
3602 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3603 DDB and LSI variants of PMON protocol mips*-*-*
3604 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3605 PowerPC with SDS protocol powerpc{,le}-*-eabi
3606 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3610 All configurations can now understand and use the DWARF 2 debugging
3611 format. The choice is automatic, if the symbol file contains DWARF 2
3616 GDB now includes basic Java language support. This support is
3617 only useful with Java compilers that produce native machine code.
3619 * solib-absolute-prefix and solib-search-path
3621 For SunOS and SVR4 shared libraries, you may now set the prefix for
3622 loading absolute shared library symbol files, and the search path for
3623 locating non-absolute shared library symbol files.
3625 * Live range splitting
3627 GDB can now effectively debug code for which GCC has performed live
3628 range splitting as part of its optimization. See gdb/doc/LRS for
3629 more details on the expected format of the stabs information.
3633 GDB's support for the GNU Hurd, including thread debugging, has been
3634 updated to work with current versions of the Hurd.
3638 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3639 instruction set. ARM GDB automatically detects when Thumb
3640 instructions are in use, and adjusts disassembly and backtracing
3645 GDB's MIPS target configurations now handle the MIP16 16-bit
3650 GDB now includes support for overlays; if an executable has been
3651 linked such that multiple sections are based at the same address, GDB
3652 will decide which section to use for symbolic info. You can choose to
3653 control the decision manually, using overlay commands, or implement
3654 additional target-side support and use "overlay load-target" to bring
3655 in the overlay mapping. Do "help overlay" for more detail.
3659 The command "info symbol <address>" displays information about
3660 the symbol at the specified address.
3664 The standard remote protocol now includes an extension that allows
3665 asynchronous collection and display of trace data. This requires
3666 extensive support in the target-side debugging stub. Tracing mode
3667 includes a new interaction mode in GDB and new commands: see the
3668 file tracepoint.c for more details.
3672 Configurations for embedded MIPS now include a simulator contributed
3673 by Cygnus Solutions. The simulator supports the instruction sets
3674 of most MIPS variants.
3678 Sparc configurations may now include the ERC32 simulator contributed
3679 by the European Space Agency. The simulator is not built into
3680 Sparc targets by default; configure with --enable-sim to include it.
3684 For target configurations that may include multiple variants of a
3685 basic architecture (such as MIPS and SH), you may now set the
3686 architecture explicitly. "set arch" sets, "info arch" lists
3687 the possible architectures.
3689 *** Changes in GDB-4.16:
3691 * New native configurations
3693 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3694 M68K NetBSD m68k-*-netbsd*
3695 PowerPC AIX 4.x powerpc-*-aix*
3696 PowerPC MacOS powerpc-*-macos*
3697 PowerPC Windows NT powerpcle-*-cygwin32
3698 RS/6000 AIX 4.x rs6000-*-aix4*
3702 ARM with RDP protocol arm-*-*
3703 I960 with MON960 i960-*-coff
3704 MIPS VxWorks mips*-*-vxworks*
3705 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3706 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3708 Matra Sparclet sparclet-*-*
3712 The powerpc-eabi configuration now includes the PSIM simulator,
3713 contributed by Andrew Cagney, with assistance from Mike Meissner.
3714 PSIM is a very elaborate model of the PowerPC, including not only
3715 basic instruction set execution, but also details of execution unit
3716 performance and I/O hardware. See sim/ppc/README for more details.
3720 GDB now works with Solaris 2.5.
3722 * Windows 95/NT native
3724 GDB will now work as a native debugger on Windows 95 and Windows NT.
3725 To build it from source, you must use the "gnu-win32" environment,
3726 which uses a DLL to emulate enough of Unix to run the GNU tools.
3727 Further information, binaries, and sources are available at
3728 ftp.cygnus.com, under pub/gnu-win32.
3730 * dont-repeat command
3732 If a user-defined command includes the command `dont-repeat', then the
3733 command will not be repeated if the user just types return. This is
3734 useful if the command is time-consuming to run, so that accidental
3735 extra keystrokes don't run the same command many times.
3737 * Send break instead of ^C
3739 The standard remote protocol now includes an option to send a break
3740 rather than a ^C to the target in order to interrupt it. By default,
3741 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3743 * Remote protocol timeout
3745 The standard remote protocol includes a new variable `remotetimeout'
3746 that allows you to set the number of seconds before GDB gives up trying
3747 to read from the target. The default value is 2.
3749 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3751 By default GDB will automatically keep track of objects as they are
3752 loaded and unloaded by the dynamic linker. By using the command `set
3753 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3754 when shared library events occur, thus allowing you to set breakpoints
3755 in shared libraries which are explicitly loaded by the inferior.
3757 Note this feature does not work on hpux8. On hpux9 you must link
3758 /usr/lib/end.o into your program. This feature should work
3759 automatically on hpux10.
3761 * Irix 5.x hardware watchpoint support
3763 Irix 5 configurations now support the use of hardware watchpoints.
3765 * Mips protocol "SYN garbage limit"
3767 When debugging a Mips target using the `target mips' protocol, you
3768 may set the number of characters that GDB will ignore by setting
3769 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3770 every character. The default value is 1050.
3772 * Recording and replaying remote debug sessions
3774 If you set `remotelogfile' to the name of a file, gdb will write to it
3775 a recording of a remote debug session. This recording may then be
3776 replayed back to gdb using "gdbreplay". See gdbserver/README for
3777 details. This is useful when you have a problem with GDB while doing
3778 remote debugging; you can make a recording of the session and send it
3779 to someone else, who can then recreate the problem.
3781 * Speedups for remote debugging
3783 GDB includes speedups for downloading and stepping MIPS systems using
3784 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3785 and more efficient S-record downloading.
3787 * Memory use reductions and statistics collection
3789 GDB now uses less memory and reports statistics about memory usage.
3790 Try the `maint print statistics' command, for example.
3792 *** Changes in GDB-4.15:
3794 * Psymtabs for XCOFF
3796 The symbol reader for AIX GDB now uses partial symbol tables. This
3797 can greatly improve startup time, especially for large executables.
3799 * Remote targets use caching
3801 Remote targets now use a data cache to speed up communication with the
3802 remote side. The data cache could lead to incorrect results because
3803 it doesn't know about volatile variables, thus making it impossible to
3804 debug targets which use memory mapped I/O devices. `set remotecache
3805 off' turns the the data cache off.
3807 * Remote targets may have threads
3809 The standard remote protocol now includes support for multiple threads
3810 in the target system, using new protocol commands 'H' and 'T'. See
3811 gdb/remote.c for details.
3815 If GDB is configured with `--enable-netrom', then it will include
3816 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3817 acts as though it is a bank of ROM on the target board, but you can
3818 write into it over the network. GDB's support consists only of
3819 support for fast loading into the emulated ROM; to debug, you must use
3820 another protocol, such as standard remote protocol. The usual
3821 sequence is something like
3823 target nrom <netrom-hostname>
3825 target remote <netrom-hostname>:1235
3829 GDB now includes support for the Apple Macintosh, as a host only. It
3830 may be run as either an MPW tool or as a standalone application, and
3831 it can debug through the serial port. All the usual GDB commands are
3832 available, but to the target command, you must supply "serial" as the
3833 device type instead of "/dev/ttyXX". See mpw-README in the main
3834 directory for more information on how to build. The MPW configuration
3835 scripts */mpw-config.in support only a few targets, and only the
3836 mips-idt-ecoff target has been tested.
3840 GDB configuration now uses autoconf. This is not user-visible,
3841 but does simplify configuration and building.
3845 GDB now supports hpux10.
3847 *** Changes in GDB-4.14:
3849 * New native configurations
3851 x86 FreeBSD i[345]86-*-freebsd
3852 x86 NetBSD i[345]86-*-netbsd
3853 NS32k NetBSD ns32k-*-netbsd
3854 Sparc NetBSD sparc-*-netbsd
3858 A29K VxWorks a29k-*-vxworks
3859 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3860 CPU32 EST-300 emulator m68*-*-est*
3861 PowerPC ELF powerpc-*-elf
3864 * Alpha OSF/1 support for procfs
3866 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3867 possible to attach to running processes. As the mounting of the /proc
3868 filesystem is optional on the Alpha, GDB automatically determines
3869 the availability of /proc during startup. This can lead to problems
3870 if /proc is unmounted after GDB has been started.
3872 * Arguments to user-defined commands
3874 User commands may accept up to 10 arguments separated by whitespace.
3875 Arguments are accessed within the user command via $arg0..$arg9. A
3878 print $arg0 + $arg1 + $arg2
3880 To execute the command use:
3883 Defines the command "adder" which prints the sum of its three arguments.
3884 Note the arguments are text substitutions, so they may reference variables,
3885 use complex expressions, or even perform inferior function calls.
3887 * New `if' and `while' commands
3889 This makes it possible to write more sophisticated user-defined
3890 commands. Both commands take a single argument, which is the
3891 expression to evaluate, and must be followed by the commands to
3892 execute, one per line, if the expression is nonzero, the list being
3893 terminated by the word `end'. The `if' command list may include an
3894 `else' word, which causes the following commands to be executed only
3895 if the expression is zero.
3897 * Fortran source language mode
3899 GDB now includes partial support for Fortran 77. It will recognize
3900 Fortran programs and can evaluate a subset of Fortran expressions, but
3901 variables and functions may not be handled correctly. GDB will work
3902 with G77, but does not yet know much about symbols emitted by other
3905 * Better HPUX support
3907 Most debugging facilities now work on dynamic executables for HPPAs
3908 running hpux9 or later. You can attach to running dynamically linked
3909 processes, but by default the dynamic libraries will be read-only, so
3910 for instance you won't be able to put breakpoints in them. To change
3911 that behavior do the following before running the program:
3917 This will cause the libraries to be mapped private and read-write.
3918 To revert to the normal behavior, do this:
3924 You cannot set breakpoints or examine data in the library until after
3925 the library is loaded if the function/data symbols do not have
3928 GDB can now also read debug symbols produced by the HP C compiler on
3929 HPPAs (sorry, no C++, Fortran or 68k support).
3931 * Target byte order now dynamically selectable
3933 You can choose which byte order to use with a target system, via the
3934 commands "set endian big" and "set endian little", and you can see the
3935 current setting by using "show endian". You can also give the command
3936 "set endian auto", in which case GDB will use the byte order
3937 associated with the executable. Currently, only embedded MIPS
3938 configurations support dynamic selection of target byte order.
3940 * New DOS host serial code
3942 This version uses DPMI interrupts to handle buffered I/O, so you
3943 no longer need to run asynctsr when debugging boards connected to
3946 *** Changes in GDB-4.13:
3948 * New "complete" command
3950 This lists all the possible completions for the rest of the line, if it
3951 were to be given as a command itself. This is intended for use by emacs.
3953 * Trailing space optional in prompt
3955 "set prompt" no longer adds a space for you after the prompt you set. This
3956 allows you to set a prompt which ends in a space or one that does not.
3958 * Breakpoint hit counts
3960 "info break" now displays a count of the number of times the breakpoint
3961 has been hit. This is especially useful in conjunction with "ignore"; you
3962 can ignore a large number of breakpoint hits, look at the breakpoint info
3963 to see how many times the breakpoint was hit, then run again, ignoring one
3964 less than that number, and this will get you quickly to the last hit of
3967 * Ability to stop printing at NULL character
3969 "set print null-stop" will cause GDB to stop printing the characters of
3970 an array when the first NULL is encountered. This is useful when large
3971 arrays actually contain only short strings.
3973 * Shared library breakpoints
3975 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3976 breakpoints in shared libraries before the executable is run.
3978 * Hardware watchpoints
3980 There is a new hardware breakpoint for the watch command for sparclite
3981 targets. See gdb/sparclite/hw_breakpoint.note.
3983 Hardware watchpoints are also now supported under GNU/Linux.
3987 Annotations have been added. These are for use with graphical interfaces,
3988 and are still experimental. Currently only gdba.el uses these.
3990 * Improved Irix 5 support
3992 GDB now works properly with Irix 5.2.
3994 * Improved HPPA support
3996 GDB now works properly with the latest GCC and GAS.
3998 * New native configurations
4000 Sequent PTX4 i[34]86-sequent-ptx4
4001 HPPA running OSF/1 hppa*-*-osf*
4002 Atari TT running SVR4 m68*-*-sysv4*
4003 RS/6000 LynxOS rs6000-*-lynxos*
4007 OS/9000 i[34]86-*-os9k
4008 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4011 * Hitachi SH7000 and E7000-PC ICE support
4013 There is now support for communicating with the Hitachi E7000-PC ICE.
4014 This is available automatically when GDB is configured for the SH.
4018 As usual, a variety of small fixes and improvements, both generic
4019 and configuration-specific. See the ChangeLog for more detail.
4021 *** Changes in GDB-4.12:
4023 * Irix 5 is now supported
4027 GDB-4.12 on the HPPA has a number of changes which make it unable
4028 to debug the output from the currently released versions of GCC and
4029 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4030 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4031 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4034 *** Changes in GDB-4.11:
4036 * User visible changes:
4040 The "set remotedebug" option is now consistent between the mips remote
4041 target, remote targets using the gdb-specific protocol, UDI (AMD's
4042 debug protocol for the 29k) and the 88k bug monitor. It is now an
4043 integer specifying a debug level (normally 0 or 1, but 2 means more
4044 debugging info for the mips target).
4046 * DEC Alpha native support
4048 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4049 debug info, but GDB works fairly well with the DEC compiler and should
4050 work with a future GCC release. See the README file for a few
4051 Alpha-specific notes.
4053 * Preliminary thread implementation
4055 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4057 * LynxOS native and target support for 386
4059 This release has been hosted on LynxOS 2.2, and also can be configured
4060 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4063 * Improvements in C++ mangling/demangling.
4065 This release has much better g++ debugging, specifically in name
4066 mangling/demangling, virtual function calls, print virtual table,
4067 call methods, ...etc.
4069 *** Changes in GDB-4.10:
4071 * User visible changes:
4073 Remote debugging using the GDB-specific (`target remote') protocol now
4074 supports the `load' command. This is only useful if you have some
4075 other way of getting the stub to the target system, and you can put it
4076 somewhere in memory where it won't get clobbered by the download.
4078 Filename completion now works.
4080 When run under emacs mode, the "info line" command now causes the
4081 arrow to point to the line specified. Also, "info line" prints
4082 addresses in symbolic form (as well as hex).
4084 All vxworks based targets now support a user settable option, called
4085 vxworks-timeout. This option represents the number of seconds gdb
4086 should wait for responses to rpc's. You might want to use this if
4087 your vxworks target is, perhaps, a slow software simulator or happens
4088 to be on the far side of a thin network line.
4092 This release contains support for using a DEC alpha as a GDB host for
4093 cross debugging. Native alpha debugging is not supported yet.
4096 *** Changes in GDB-4.9:
4100 This is the first GDB release which is accompanied by a matching testsuite.
4101 The testsuite requires installation of dejagnu, which should be available
4102 via ftp from most sites that carry GNU software.
4106 'Cfront' style demangling has had its name changed to 'ARM' style, to
4107 emphasize that it was written from the specifications in the C++ Annotated
4108 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4109 disclaimers, it still generated too much confusion with users attempting to
4110 use gdb with AT&T cfront.
4114 GDB now uses a standard remote interface to a simulator library.
4115 So far, the library contains simulators for the Zilog Z8001/2, the
4116 Hitachi H8/300, H8/500 and Super-H.
4118 * New targets supported
4120 H8/300 simulator h8300-hitachi-hms or h8300hms
4121 H8/500 simulator h8500-hitachi-hms or h8500hms
4122 SH simulator sh-hitachi-hms or sh
4123 Z8000 simulator z8k-zilog-none or z8ksim
4124 IDT MIPS board over serial line mips-idt-ecoff
4126 Cross-debugging to GO32 targets is supported. It requires a custom
4127 version of the i386-stub.c module which is integrated with the
4128 GO32 memory extender.
4130 * New remote protocols
4132 MIPS remote debugging protocol.
4134 * New source languages supported
4136 This version includes preliminary support for Chill, a Pascal like language
4137 used by telecommunications companies. Chill support is also being integrated
4138 into the GNU compiler, but we don't know when it will be publically available.
4141 *** Changes in GDB-4.8:
4143 * HP Precision Architecture supported
4145 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4146 version of this support was available as a set of patches from the
4147 University of Utah. GDB does not support debugging of programs
4148 compiled with the HP compiler, because HP will not document their file
4149 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4150 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4152 Many problems in the preliminary version have been fixed.
4154 * Faster and better demangling
4156 We have improved template demangling and fixed numerous bugs in the GNU style
4157 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4158 character types (wchar_t) are now supported. Demangling of each symbol is now
4159 only done once, and is cached when the symbol table for a file is read in.
4160 This results in a small increase in memory usage for C programs, a moderate
4161 increase in memory usage for C++ programs, and a fantastic speedup in
4164 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4165 from the specifications in the Annotated Reference Manual, which AT&T's
4166 compiler does not actually implement.
4168 * G++ multiple inheritance compiler problem
4170 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4171 inheritance lattices was reworked to properly discover ambiguities. We
4172 recently found an example which causes this new algorithm to fail in a
4173 very subtle way, producing bad debug information for those classes.
4174 The file 'gcc.patch' (in this directory) can be applied to gcc to
4175 circumvent the problem. A future GCC release will contain a complete
4178 The previous G++ debug info problem (mentioned below for the gdb-4.7
4179 release) is fixed in gcc version 2.3.2.
4181 * Improved configure script
4183 The `configure' script will now attempt to guess your system type if
4184 you don't supply a host system type. The old scheme of supplying a
4185 host system triplet is preferable over using this. All the magic is
4186 done in the new `config.guess' script. Examine it for details.
4188 We have also brought our configure script much more in line with the FSF's
4189 version. It now supports the --with-xxx options. In particular,
4190 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4191 The resulting GDB will not be able to read arbitrary object file formats --
4192 only the format ``expected'' to be used on the configured target system.
4193 We hope to make this the default in a future release.
4195 * Documentation improvements
4197 There's new internal documentation on how to modify GDB, and how to
4198 produce clean changes to the code. We implore people to read it
4199 before submitting changes.
4201 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4202 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4203 `info' files are also provided. To build `info' files from scratch,
4204 you will need the latest `makeinfo' release, which will be available in
4205 a future texinfo-X.Y release.
4207 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4208 We're not sure exactly which versions have this problem, but it has
4209 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4210 or better. If that isn't possible, there is a patch in
4211 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4212 around this problem.
4216 GDB now supports array constants that can be used in expressions typed in by
4217 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4218 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4221 The new directory `gdb/sparclite' contains a program that demonstrates
4222 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4224 * New native hosts supported
4226 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4227 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4229 * New targets supported
4231 AMD 29k family via UDI a29k-amd-udi or udi29k
4233 * New file formats supported
4235 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4236 HPUX core files, and SCO 3.2v2 core files.
4240 Attaching to processes now works again; thanks for the many bug reports.
4242 We have also stomped on a bunch of core dumps caused by
4243 printf_filtered("%s") problems.
4245 We eliminated a copyright problem on the rpc and ptrace header files
4246 for VxWorks, which was discovered at the last minute during the 4.7
4247 release. You should now be able to build a VxWorks GDB.
4249 You can now interrupt gdb while an attached process is running. This
4250 will cause the attached process to stop, and give control back to GDB.
4252 We fixed problems caused by using too many file descriptors
4253 for reading symbols from object files and libraries. This was
4254 especially a problem for programs that used many (~100) shared
4257 The `step' command now only enters a subroutine if there is line number
4258 information for the subroutine. Otherwise it acts like the `next'
4259 command. Previously, `step' would enter subroutines if there was
4260 any debugging information about the routine. This avoids problems
4261 when using `cc -g1' on MIPS machines.
4263 * Internal improvements
4265 GDB's internal interfaces have been improved to make it easier to support
4266 debugging of multiple languages in the future.
4268 GDB now uses a common structure for symbol information internally.
4269 Minimal symbols (derived from linkage symbols in object files), partial
4270 symbols (from a quick scan of debug information), and full symbols
4271 contain a common subset of information, making it easier to write
4272 shared code that handles any of them.
4274 * New command line options
4276 We now accept --silent as an alias for --quiet.
4280 The memory-mapped-malloc library is now licensed under the GNU Library
4281 General Public License.
4283 *** Changes in GDB-4.7:
4285 * Host/native/target split
4287 GDB has had some major internal surgery to untangle the support for
4288 hosts and remote targets. Now, when you configure GDB for a remote
4289 target, it will no longer load in all of the support for debugging
4290 local programs on the host. When fully completed and tested, this will
4291 ensure that arbitrary host/target combinations are possible.
4293 The primary conceptual shift is to separate the non-portable code in
4294 GDB into three categories. Host specific code is required any time GDB
4295 is compiled on that host, regardless of the target. Target specific
4296 code relates to the peculiarities of the target, but can be compiled on
4297 any host. Native specific code is everything else: it can only be
4298 built when the host and target are the same system. Child process
4299 handling and core file support are two common `native' examples.
4301 GDB's use of /proc for controlling Unix child processes is now cleaner.
4302 It has been split out into a single module under the `target_ops' vector,
4303 plus two native-dependent functions for each system that uses /proc.
4305 * New hosts supported
4307 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4308 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4309 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4311 * New targets supported
4313 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4314 68030 and CPU32 m68030-*-*, m68332-*-*
4316 * New native hosts supported
4318 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4319 (386bsd is not well tested yet)
4320 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4322 * New file formats supported
4324 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4325 supports reading of `a.out.adobe' object files, which are an a.out
4326 format extended with minimal information about multiple sections.
4330 `show copying' is the same as the old `info copying'.
4331 `show warranty' is the same as `info warrantee'.
4332 These were renamed for consistency. The old commands continue to work.
4334 `info handle' is a new alias for `info signals'.
4336 You can now define pre-command hooks, which attach arbitrary command
4337 scripts to any command. The commands in the hook will be executed
4338 prior to the user's command. You can also create a hook which will be
4339 executed whenever the program stops. See gdb.texinfo.
4343 We now deal with Cfront style name mangling, and can even extract type
4344 info from mangled symbols. GDB can automatically figure out which
4345 symbol mangling style your C++ compiler uses.
4347 Calling of methods and virtual functions has been improved as well.
4351 The crash that occured when debugging Sun Ansi-C compiled binaries is
4352 fixed. This was due to mishandling of the extra N_SO stabs output
4355 We also finally got Ultrix 4.2 running in house, and fixed core file
4356 support, with help from a dozen people on the net.
4358 John M. Farrell discovered that the reason that single-stepping was so
4359 slow on all of the Mips based platforms (primarily SGI and DEC) was
4360 that we were trying to demangle and lookup a symbol used for internal
4361 purposes on every instruction that was being stepped through. Changing
4362 the name of that symbol so that it couldn't be mistaken for a C++
4363 mangled symbol sped things up a great deal.
4365 Rich Pixley sped up symbol lookups in general by getting much smarter
4366 about when C++ symbol mangling is necessary. This should make symbol
4367 completion (TAB on the command line) much faster. It's not as fast as
4368 we'd like, but it's significantly faster than gdb-4.6.
4372 A new user controllable variable 'call_scratch_address' can
4373 specify the location of a scratch area to be used when GDB
4374 calls a function in the target. This is necessary because the
4375 usual method of putting the scratch area on the stack does not work
4376 in systems that have separate instruction and data spaces.
4378 We integrated changes to support the 29k UDI (Universal Debugger
4379 Interface), but discovered at the last minute that we didn't have all
4380 of the appropriate copyright paperwork. We are working with AMD to
4381 resolve this, and hope to have it available soon.
4385 We have sped up the remote serial line protocol, especially for targets
4386 with lots of registers. It now supports a new `expedited status' ('T')
4387 message which can be used in place of the existing 'S' status message.
4388 This allows the remote stub to send only the registers that GDB
4389 needs to make a quick decision about single-stepping or conditional
4390 breakpoints, eliminating the need to fetch the entire register set for
4391 each instruction being stepped through.
4393 The GDB remote serial protocol now implements a write-through cache for
4394 registers, only re-reading the registers if the target has run.
4396 There is also a new remote serial stub for SPARC processors. You can
4397 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4398 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4399 processor with a serial port.
4403 Configure.in files have become much easier to read and modify. A new
4404 `table driven' format makes it more obvious what configurations are
4405 supported, and what files each one uses.
4409 There is a new opcodes library which will eventually contain all of the
4410 disassembly routines and opcode tables. At present, it only contains
4411 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4412 disassembler (binutils/objdump) to share these routines.
4414 The libiberty library is now copylefted under the GNU Library General
4415 Public License. This allows more liberal use, and was done so libg++
4416 can use it. This makes no difference to GDB, since the Library License
4417 grants all the rights from the General Public License.
4421 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4422 reference to the stabs symbol info used by the debugger. It is (as far
4423 as we know) the only published document on this fascinating topic. We
4424 encourage you to read it, compare it to the stabs information on your
4425 system, and send improvements on the document in general (to
4426 bug-gdb@prep.ai.mit.edu).
4428 And, of course, many bugs have been fixed.
4431 *** Changes in GDB-4.6:
4433 * Better support for C++ function names
4435 GDB now accepts as input the "demangled form" of C++ overloaded function
4436 names and member function names, and can do command completion on such names
4437 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4438 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4439 Make use of command completion, it is your friend.
4441 GDB also now accepts a variety of C++ mangled symbol formats. They are
4442 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4443 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4444 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4445 for the list of formats.
4447 * G++ symbol mangling problem
4449 Recent versions of gcc have a bug in how they emit debugging information for
4450 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4451 directory) can be applied to gcc to fix the problem. Alternatively, if you
4452 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4453 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4454 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4457 * New 'maintenance' command
4459 All of the commands related to hacking GDB internals have been moved out of
4460 the main command set, and now live behind the 'maintenance' command. This
4461 can also be abbreviated as 'mt'. The following changes were made:
4463 dump-me -> maintenance dump-me
4464 info all-breakpoints -> maintenance info breakpoints
4465 printmsyms -> maintenance print msyms
4466 printobjfiles -> maintenance print objfiles
4467 printpsyms -> maintenance print psymbols
4468 printsyms -> maintenance print symbols
4470 The following commands are new:
4472 maintenance demangle Call internal GDB demangler routine to
4473 demangle a C++ link name and prints the result.
4474 maintenance print type Print a type chain for a given symbol
4476 * Change to .gdbinit file processing
4478 We now read the $HOME/.gdbinit file before processing the argv arguments
4479 (e.g. reading symbol files or core files). This allows global parameters to
4480 be set, which will apply during the symbol reading. The ./.gdbinit is still
4481 read after argv processing.
4483 * New hosts supported
4485 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4487 GNU/Linux support i386-unknown-linux or linux
4489 We are also including code to support the HP/PA running BSD and HPUX. This
4490 is almost guaranteed not to work, as we didn't have time to test or build it
4491 for this release. We are including it so that the more adventurous (or
4492 masochistic) of you can play with it. We also had major problems with the
4493 fact that the compiler that we got from HP doesn't support the -g option.
4496 * New targets supported
4498 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4500 * More smarts about finding #include files
4502 GDB now remembers the compilation directory for all include files, and for
4503 all files from which C is generated (like yacc and lex sources). This
4504 greatly improves GDB's ability to find yacc/lex sources, and include files,
4505 especially if you are debugging your program from a directory different from
4506 the one that contains your sources.
4508 We also fixed a bug which caused difficulty with listing and setting
4509 breakpoints in include files which contain C code. (In the past, you had to
4510 try twice in order to list an include file that you hadn't looked at before.)
4512 * Interesting infernals change
4514 GDB now deals with arbitrary numbers of sections, where the symbols for each
4515 section must be relocated relative to that section's landing place in the
4516 target's address space. This work was needed to support ELF with embedded
4517 stabs used by Solaris-2.0.
4519 * Bug fixes (of course!)
4521 There have been loads of fixes for the following things:
4522 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4523 i960, stabs, DOS(GO32), procfs, etc...
4525 See the ChangeLog for details.
4527 *** Changes in GDB-4.5:
4529 * New machines supported (host and target)
4531 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4533 SGI Irix-4.x mips-sgi-irix4 or iris4
4535 * New malloc package
4537 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4538 Mmalloc is capable of handling mutiple heaps of memory. It is also
4539 capable of saving a heap to a file, and then mapping it back in later.
4540 This can be used to greatly speedup the startup of GDB by using a
4541 pre-parsed symbol table which lives in a mmalloc managed heap. For
4542 more details, please read mmalloc/mmalloc.texi.
4546 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4547 'help info proc' for details.
4549 * MIPS ecoff symbol table format
4551 The code that reads MIPS symbol table format is now supported on all hosts.
4552 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4555 * File name changes for MS-DOS
4557 Many files in the config directories have been renamed to make it easier to
4558 support GDB on MS-DOSe systems (which have very restrictive file name
4559 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4560 environment) is close to working but has some remaining problems. Note
4561 that debugging of DOS programs is not supported, due to limitations
4562 in the ``operating system'', but it can be used to host cross-debugging.
4564 * Cross byte order fixes
4566 Many fixes have been made to support cross debugging of Sparc and MIPS
4567 targets from hosts whose byte order differs.
4569 * New -mapped and -readnow options
4571 If memory-mapped files are available on your system through the 'mmap'
4572 system call, you can use the -mapped option on the `file' or
4573 `symbol-file' commands to cause GDB to write the symbols from your
4574 program into a reusable file. If the program you are debugging is
4575 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4576 Future GDB debugging sessions will notice the presence of this file,
4577 and will quickly map in symbol information from it, rather than reading
4578 the symbol table from the executable program. Using the '-mapped'
4579 option in a GDB `file' or `symbol-file' command has the same effect as
4580 starting GDB with the '-mapped' command-line option.
4582 You can cause GDB to read the entire symbol table immediately by using
4583 the '-readnow' option with any of the commands that load symbol table
4584 information (or on the GDB command line). This makes the command
4585 slower, but makes future operations faster.
4587 The -mapped and -readnow options are typically combined in order to
4588 build a `fred.syms' file that contains complete symbol information.
4589 A simple GDB invocation to do nothing but build a `.syms' file for future
4592 gdb -batch -nx -mapped -readnow programname
4594 The `.syms' file is specific to the host machine on which GDB is run.
4595 It holds an exact image of GDB's internal symbol table. It cannot be
4596 shared across multiple host platforms.
4598 * longjmp() handling
4600 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4601 siglongjmp() without losing control. This feature has not yet been ported to
4602 all systems. It currently works on many 386 platforms, all MIPS-based
4603 platforms (SGI, DECstation, etc), and Sun3/4.
4607 Preliminary work has been put in to support the new Solaris OS from Sun. At
4608 this time, it can control and debug processes, but it is not capable of
4613 As always, many many bug fixes. The major areas were with g++, and mipsread.
4614 People using the MIPS-based platforms should experience fewer mysterious
4615 crashes and trashed symbol tables.
4617 *** Changes in GDB-4.4:
4619 * New machines supported (host and target)
4621 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4623 BSD Reno on Vax vax-dec-bsd
4624 Ultrix on Vax vax-dec-ultrix
4626 * New machines supported (target)
4628 AMD 29000 embedded, using EBMON a29k-none-none
4632 GDB continues to improve its handling of C++. `References' work better.
4633 The demangler has also been improved, and now deals with symbols mangled as
4634 per the Annotated C++ Reference Guide.
4636 GDB also now handles `stabs' symbol information embedded in MIPS
4637 `ecoff' symbol tables. Since the ecoff format was not easily
4638 extensible to handle new languages such as C++, this appeared to be a
4639 good way to put C++ debugging info into MIPS binaries. This option
4640 will be supported in the GNU C compiler, version 2, when it is
4643 * New features for SVR4
4645 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4646 shared libraries. Debugging dynamically linked programs should present
4647 only minor differences from debugging statically linked programs.
4649 The `info proc' command will print out information about any process
4650 on an SVR4 system (including the one you are debugging). At the moment,
4651 it prints the address mappings of the process.
4653 If you bring up GDB on another SVR4 system, please send mail to
4654 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4656 * Better dynamic linking support in SunOS
4658 Reading symbols from shared libraries which contain debugging symbols
4659 now works properly. However, there remain issues such as automatic
4660 skipping of `transfer vector' code during function calls, which
4661 make it harder to debug code in a shared library, than to debug the
4662 same code linked statically.
4666 GDB is now using the latest `getopt' routines from the FSF. This
4667 version accepts the -- prefix for options with long names. GDB will
4668 continue to accept the old forms (-option and +option) as well.
4669 Various single letter abbreviations for options have been explicity
4670 added to the option table so that they won't get overshadowed in the
4671 future by other options that begin with the same letter.
4675 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4676 Many assorted bugs have been handled. Many more remain to be handled.
4677 See the various ChangeLog files (primarily in gdb and bfd) for details.
4680 *** Changes in GDB-4.3:
4682 * New machines supported (host and target)
4684 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4685 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4686 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4688 * Almost SCO Unix support
4690 We had hoped to support:
4691 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4692 (except for core file support), but we discovered very late in the release
4693 that it has problems with process groups that render gdb unusable. Sorry
4694 about that. I encourage people to fix it and post the fixes.
4696 * Preliminary ELF and DWARF support
4698 GDB can read ELF object files on System V Release 4, and can handle
4699 debugging records for C, in DWARF format, in ELF files. This support
4700 is preliminary. If you bring up GDB on another SVR4 system, please
4701 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4706 GDB now uses the latest `readline' library. One user-visible change
4707 is that two tabs will list possible command completions, which previously
4708 required typing M-? (meta-question mark, or ESC ?).
4712 The `stepi' bug that many of you noticed has been squashed.
4713 Many bugs in C++ have been handled. Many more remain to be handled.
4714 See the various ChangeLog files (primarily in gdb and bfd) for details.
4716 * State of the MIPS world (in case you wondered):
4718 GDB can understand the symbol tables emitted by the compilers
4719 supplied by most vendors of MIPS-based machines, including DEC. These
4720 symbol tables are in a format that essentially nobody else uses.
4722 Some versions of gcc come with an assembler post-processor called
4723 mips-tfile. This program is required if you want to do source-level
4724 debugging of gcc-compiled programs. I believe FSF does not ship
4725 mips-tfile with gcc version 1, but it will eventually come with gcc
4728 Debugging of g++ output remains a problem. g++ version 1.xx does not
4729 really support it at all. (If you're lucky, you should be able to get
4730 line numbers and stack traces to work, but no parameters or local
4731 variables.) With some work it should be possible to improve the
4734 When gcc version 2 is released, you will have somewhat better luck.
4735 However, even then you will get confusing results for inheritance and
4738 We will eventually provide full debugging of g++ output on
4739 DECstations. This will probably involve some kind of stabs-in-ecoff
4740 encapulation, but the details have not been worked out yet.
4743 *** Changes in GDB-4.2:
4745 * Improved configuration
4747 Only one copy of `configure' exists now, and it is not self-modifying.
4748 Porting BFD is simpler.
4752 The `step' and `next' commands now only stop at the first instruction
4753 of a source line. This prevents the multiple stops that used to occur
4754 in switch statements, for-loops, etc. `Step' continues to stop if a
4755 function that has debugging information is called within the line.
4759 Lots of small bugs fixed. More remain.
4761 * New host supported (not target)
4763 Intel 386 PC clone running Mach i386-none-mach
4766 *** Changes in GDB-4.1:
4768 * Multiple source language support
4770 GDB now has internal scaffolding to handle several source languages.
4771 It determines the type of each source file from its filename extension,
4772 and will switch expression parsing and number formatting to match the
4773 language of the function in the currently selected stack frame.
4774 You can also specifically set the language to be used, with
4775 `set language c' or `set language modula-2'.
4779 GDB now has preliminary support for the GNU Modula-2 compiler,
4780 currently under development at the State University of New York at
4781 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4782 continue through the fall of 1991 and into 1992.
4784 Other Modula-2 compilers are currently not supported, and attempting to
4785 debug programs compiled with them will likely result in an error as the
4786 symbol table is read. Feel free to work on it, though!
4788 There are hooks in GDB for strict type checking and range checking,
4789 in the `Modula-2 philosophy', but they do not currently work.
4793 GDB can now write to executable and core files (e.g. patch
4794 a variable's value). You must turn this switch on, specify
4795 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4796 by assigning a new value to a variable. Modifications take
4799 * Automatic SunOS shared library reading
4801 When you run your program, GDB automatically determines where its
4802 shared libraries (if any) have been loaded, and reads their symbols.
4803 The `share' command is no longer needed. This also works when
4804 examining core files.
4808 You can specify the number of lines that the `list' command shows.
4811 * New machines supported (host and target)
4813 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4814 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4815 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4817 * New hosts supported (not targets)
4819 IBM RT/PC: romp-ibm-aix or rtpc
4821 * New targets supported (not hosts)
4823 AMD 29000 embedded with COFF a29k-none-coff
4824 AMD 29000 embedded with a.out a29k-none-aout
4825 Ultracomputer remote kernel debug a29k-nyu-kern
4827 * New remote interfaces
4833 *** Changes in GDB-4.0:
4837 Wide output is wrapped at good places to make the output more readable.
4839 Gdb now supports cross-debugging from a host machine of one type to a
4840 target machine of another type. Communication with the target system
4841 is over serial lines. The ``target'' command handles connecting to the
4842 remote system; the ``load'' command will download a program into the
4843 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4844 also supports debugging of realtime processes running under VxWorks,
4845 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4846 stub on the target system.
4848 New CPUs supported include the AMD 29000 and Intel 960.
4850 GDB now reads object files and symbol tables via a ``binary file''
4851 library, which allows a single copy of GDB to debug programs of multiple
4852 object file types such as a.out and coff.
4854 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4855 refcard.dvi and refcard.ps are available to format it).
4858 * Control-Variable user interface simplified
4860 All variables that control the operation of the debugger can be set
4861 by the ``set'' command, and displayed by the ``show'' command.
4863 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4864 ``Show prompt'' produces the response:
4865 Gdb's prompt is new-gdb=>.
4867 What follows are the NEW set commands. The command ``help set'' will
4868 print a complete list of old and new set commands. ``help set FOO''
4869 will give a longer description of the variable FOO. ``show'' will show
4870 all of the variable descriptions and their current settings.
4872 confirm on/off: Enables warning questions for operations that are
4873 hard to recover from, e.g. rerunning the program while
4874 it is already running. Default is ON.
4876 editing on/off: Enables EMACS style command line editing
4877 of input. Previous lines can be recalled with
4878 control-P, the current line can be edited with control-B,
4879 you can search for commands with control-R, etc.
4882 history filename NAME: NAME is where the gdb command history
4883 will be stored. The default is .gdb_history,
4884 or the value of the environment variable
4887 history size N: The size, in commands, of the command history. The
4888 default is 256, or the value of the environment variable
4891 history save on/off: If this value is set to ON, the history file will
4892 be saved after exiting gdb. If set to OFF, the
4893 file will not be saved. The default is OFF.
4895 history expansion on/off: If this value is set to ON, then csh-like
4896 history expansion will be performed on
4897 command line input. The default is OFF.
4899 radix N: Sets the default radix for input and output. It can be set
4900 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4901 in the current radix, so "set radix 10" is always a no-op.
4903 height N: This integer value is the number of lines on a page. Default
4904 is 24, the current `stty rows'' setting, or the ``li#''
4905 setting from the termcap entry matching the environment
4908 width N: This integer value is the number of characters on a line.
4909 Default is 80, the current `stty cols'' setting, or the ``co#''
4910 setting from the termcap entry matching the environment
4913 Note: ``set screensize'' is obsolete. Use ``set height'' and
4914 ``set width'' instead.
4916 print address on/off: Print memory addresses in various command displays,
4917 such as stack traces and structure values. Gdb looks
4918 more ``symbolic'' if you turn this off; it looks more
4919 ``machine level'' with it on. Default is ON.
4921 print array on/off: Prettyprint arrays. New convenient format! Default
4924 print demangle on/off: Print C++ symbols in "source" form if on,
4927 print asm-demangle on/off: Same, for assembler level printouts
4930 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4933 * Support for Epoch Environment.
4935 The epoch environment is a version of Emacs v18 with windowing. One
4936 new command, ``inspect'', is identical to ``print'', except that if you
4937 are running in the epoch environment, the value is printed in its own
4941 * Support for Shared Libraries
4943 GDB can now debug programs and core files that use SunOS shared libraries.
4944 Symbols from a shared library cannot be referenced
4945 before the shared library has been linked with the program (this
4946 happens after you type ``run'' and before the function main() is entered).
4947 At any time after this linking (including when examining core files
4948 from dynamically linked programs), gdb reads the symbols from each
4949 shared library when you type the ``sharedlibrary'' command.
4950 It can be abbreviated ``share''.
4952 sharedlibrary REGEXP: Load shared object library symbols for files
4953 matching a unix regular expression. No argument
4954 indicates to load symbols for all shared libraries.
4956 info sharedlibrary: Status of loaded shared libraries.
4961 A watchpoint stops execution of a program whenever the value of an
4962 expression changes. Checking for this slows down execution
4963 tremendously whenever you are in the scope of the expression, but is
4964 quite useful for catching tough ``bit-spreader'' or pointer misuse
4965 problems. Some machines such as the 386 have hardware for doing this
4966 more quickly, and future versions of gdb will use this hardware.
4968 watch EXP: Set a watchpoint (breakpoint) for an expression.
4970 info watchpoints: Information about your watchpoints.
4972 delete N: Deletes watchpoint number N (same as breakpoints).
4973 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4974 enable N: Re-enables watchpoint number N (same as breakpoints).
4977 * C++ multiple inheritance
4979 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4982 * C++ exception handling
4984 Gdb now supports limited C++ exception handling. Besides the existing
4985 ability to breakpoint on an exception handler, gdb can breakpoint on
4986 the raising of an exception (before the stack is peeled back to the
4989 catch FOO: If there is a FOO exception handler in the dynamic scope,
4990 set a breakpoint to catch exceptions which may be raised there.
4991 Multiple exceptions (``catch foo bar baz'') may be caught.
4993 info catch: Lists all exceptions which may be caught in the
4994 current stack frame.
4997 * Minor command changes
4999 The command ``call func (arg, arg, ...)'' now acts like the print
5000 command, except it does not print or save a value if the function's result
5001 is void. This is similar to dbx usage.
5003 The ``up'' and ``down'' commands now always print the frame they end up
5004 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5005 frames without printing.
5007 * New directory command
5009 'dir' now adds directories to the FRONT of the source search path.
5010 The path starts off empty. Source files that contain debug information
5011 about the directory in which they were compiled can be found even
5012 with an empty path; Sun CC and GCC include this information. If GDB can't
5013 find your source file in the current directory, type "dir .".
5015 * Configuring GDB for compilation
5017 For normal use, type ``./configure host''. See README or gdb.texinfo
5020 GDB now handles cross debugging. If you are remotely debugging between
5021 two different machines, type ``./configure host -target=targ''.
5022 Host is the machine where GDB will run; targ is the machine
5023 where the program that you are debugging will run.