1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
6 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
7 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
8 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
9 options and inspect the probe arguments using the new $_probe_arg family
10 of convenience variables. You can obtain more information about SystemTap
11 in <http://sourceware.org/systemtap/>.
13 * GDB now supports reversible debugging on ARM, it allows you to
14 debug basic ARM and THUMB instructions, and provides
15 record/replay support.
17 * The option "symbol-reloading" has been deleted as it is no longer used.
21 ** GDB commands implemented in Python can now be put in command class
24 ** The "maint set python print-stack on|off" is now deleted.
26 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
27 apply "flag enum"-style pretty-printing to any enum.
29 ** gdb.lookup_symbol can now work when there is no current frame.
31 ** gdb.Symbol now has a 'line' attribute, holding the line number in
32 the source at which the symbol was defined.
34 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
35 method 'value'. The former indicates whether the symbol needs a
36 frame in order to compute its value, and the latter computes the
39 ** A new method 'referenced_value' on gdb.Value objects which can
40 dereference pointer as well as C++ reference values.
42 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
43 which return the global and static blocks (as gdb.Block objects),
44 of the underlying symbol table, respectively.
46 * Go language support.
47 GDB now supports debugging programs written in the Go programming
50 * GDBserver now supports stdio connections.
51 E.g. (gdb) target remote | ssh myhost gdbserver - hello
53 * The binary "gdbtui" can no longer be built or installed.
54 Use "gdb -tui" instead.
56 * GDB will now print "flag" enums specially. A flag enum is one where
57 all the enumerator values have no bits in common when pairwise
58 "and"ed. When printing a value whose type is a flag enum, GDB will
59 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
60 (gdb) print (enum E) 3
63 * The filename part of a linespec will now match trailing components
64 of a source file name. For example, "break gcc/expr.c:1000" will
65 now set a breakpoint in build/gcc/expr.c, but not
68 * The "info proc" and "generate-core-file" commands will now also
69 work on remote targets connected to GDBserver on Linux.
71 * The command "info catch" has been removed. It has been disabled
74 * The "catch exception" and "catch assert" commands now accept
75 a condition at the end of the command, much like the "break"
76 command does. For instance:
78 (gdb) catch exception Constraint_Error if Barrier = True
80 Previously, it was possible to add a condition to such catchpoints,
81 but it had to be done as a second step, after the catchpoint had been
82 created, using the "condition" command.
84 * The "info static-tracepoint-marker" command will now also work on
85 native Linux targets with in-process agent.
87 * GDB can now set breakpoints on inlined functions.
89 * The .gdb_index section has been updated to include symbols for
90 inlined functions. GDB will ignore older .gdb_index sections by
91 default, which could cause symbol files to be loaded more slowly
92 until their .gdb_index sections can be recreated. The new option
93 --use-deprecated-index-sections will cause GDB to use any older
94 .gdb_index sections it finds. This will restore performance, but
95 the ability to set breakpoints on inlined functions will be lost
96 in symbol files with older .gdb_index sections.
98 * Ada support for GDB/MI Variable Objects has been added.
100 * GDB can now support 'breakpoint always-inserted mode' in 'record'
105 ** "catch load" and "catch unload" can be used to stop when a shared
106 library is loaded or unloaded, respectively.
108 ** "enable count" can be used to auto-disable a breakpoint after
111 ** "info vtbl" can be used to show the virtual method tables for
112 C++ and Java objects.
114 ** "explore" and its sub commands "explore value" and "explore type"
115 can be used to reccursively explore values and types of
116 expressions. These commands are available only if GDB is
117 configured with '--with-python'.
119 ** "info auto-load" shows status of all kinds of auto-loaded files,
120 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
121 sequences of commands files, "info auto-load python-scripts"
122 shows status of auto-loading Python script files,
123 "info auto-load local-gdbinit" shows status of loading init file
124 (.gdbinit) from current directory and "info auto-load libthread-db" shows
125 status of inferior specific thread debugging shared library loading.
127 ** "info auto-load-scripts", "set auto-load-scripts on|off"
128 and "show auto-load-scripts" commands have been deprecated, use their
129 "info auto-load python-scripts", "set auto-load python-scripts on|off"
130 and "show auto-load python-scripts" counterparts instead.
134 Renesas RL78 rl78-*-elf
135 HP OpenVMS ia64 ia64-hp-openvms*
137 * GDBserver supports evaluation of breakpoint conditions. When
138 support is advertised by GDBserver, GDB may be told to send the
139 breakpoint conditions in bytecode form to GDBserver. GDBserver
140 will only report the breakpoint trigger to GDB when its condition
145 set breakpoint condition-evaluation
146 show breakpoint condition-evaluation
147 Control whether breakpoint conditions are evaluated by GDB ("host") or by
148 GDBserver ("target"). Default option "auto" chooses the most efficient
150 This option can improve debugger efficiency depending on the speed of the
154 Disable auto-loading globally.
157 Show auto-loading setting of all kinds of auto-loaded files.
159 set auto-load gdb-scripts on|off
160 show auto-load gdb-scripts
161 Control auto-loading of GDB canned sequences of commands files.
163 set auto-load python-scripts on|off
164 show auto-load python-scripts
165 Control auto-loading of Python script files.
167 set auto-load local-gdbinit on|off
168 show auto-load local-gdbinit
169 Control loading of init file (.gdbinit) from current directory.
171 set auto-load libthread-db on|off
172 show auto-load libthread-db
173 Control auto-loading of inferior specific thread debugging shared library.
175 set auto-load safe-path <dir1>[:<dir2>...]
176 show auto-load safe-path
177 Set a list of directories from which it is safe to auto-load files.
178 The delimiter (':' above) may differ according to the host platform.
180 set debug auto-load on|off
182 Control display of debugging info for auto-loading the files above.
186 z0/z1 conditional breakpoints extension
188 The z0/z1 breakpoint insertion packets have been extended to carry
189 a list of conditional expressions over to the remote stub depending on the
190 condition evaluation mode. The use of this extension can be controlled
191 via the "set remote conditional-breakpoints-packet" command.
195 Specify the signals which the remote stub may pass to the debugged
196 program without GDB involvement.
198 * New command line options
200 --init-command=FILE, -ix Like --command, -x but execute it
201 before loading inferior.
202 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
203 execute it before loading inferior.
205 *** Changes in GDB 7.4
207 * GDB now handles ambiguous linespecs more consistently; the existing
208 FILE:LINE support has been expanded to other types of linespecs. A
209 breakpoint will now be set on all matching locations in all
210 inferiors, and locations will be added or removed according to
213 * GDB now allows you to skip uninteresting functions and files when
214 stepping with the "skip function" and "skip file" commands.
216 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
217 and "show remote hardware-watchpoint-length-limit". These allows to
218 set or show the maximum length limit (in bytes) of a remote
219 target hardware watchpoint.
221 This allows e.g. to use "unlimited" hardware watchpoints with the
222 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
223 watchpoints are slower than real hardware watchpoints but are
224 significantly faster than gdb software watchpoints.
228 ** The register_pretty_printer function in module gdb.printing now takes
229 an optional `replace' argument. If True, the new printer replaces any
232 ** The "maint set python print-stack on|off" command has been
233 deprecated and will be deleted in GDB 7.5.
234 A new command: "set python print-stack none|full|message" has
235 replaced it. Additionally, the default for "print-stack" is
236 now "message", which just prints the error message without
239 ** A prompt substitution hook (prompt_hook) is now available to the
242 ** A new Python module, gdb.prompt has been added to the GDB Python
243 modules library. This module provides functionality for
244 escape sequences in prompts (used by set/show
245 extended-prompt). These escape sequences are replaced by their
248 ** Python commands and convenience-functions located in
249 'data-directory'/python/gdb/command and
250 'data-directory'/python/gdb/function are now automatically loaded
253 ** Blocks now provide four new attributes. global_block and
254 static_block will return the global and static blocks
255 respectively. is_static and is_global are boolean attributes
256 that indicate if the block is one of those two types.
258 ** Symbols now provide the "type" attribute, the type of the symbol.
260 ** The "gdb.breakpoint" function has been deprecated in favor of
263 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
264 of a function. This class is based on the "finish" command
265 available in the CLI.
267 ** Type objects for struct and union types now allow access to
268 the fields using standard Python dictionary (mapping) methods.
269 For example, "some_type['myfield']" now works, as does
272 ** A new event "gdb.new_objfile" has been added, triggered by loading a
275 ** A new function, "deep_items" has been added to the gdb.types
276 module in the GDB Python modules library. This function returns
277 an iterator over the fields of a struct or union type. Unlike
278 the standard Python "iteritems" method, it will recursively traverse
279 any anonymous fields.
283 ** "*stopped" events can report several new "reason"s, such as
286 ** Breakpoint changes are now notified using new async records, like
287 "=breakpoint-modified".
289 ** New command -ada-task-info.
291 * libthread-db-search-path now supports two special values: $sdir and $pdir.
292 $sdir specifies the default system locations of shared libraries.
293 $pdir specifies the directory where the libpthread used by the application
296 GDB no longer looks in $sdir and $pdir after it has searched the directories
297 mentioned in libthread-db-search-path. If you want to search those
298 directories, they must be specified in libthread-db-search-path.
299 The default value of libthread-db-search-path on GNU/Linux and Solaris
300 systems is now "$sdir:$pdir".
302 $pdir is not supported by gdbserver, it is currently ignored.
303 $sdir is supported by gdbserver.
305 * New configure option --with-iconv-bin.
306 When using the internationalization support like the one in the GNU C
307 library, GDB will invoke the "iconv" program to get a list of supported
308 character sets. If this program lives in a non-standard location, one can
309 use this option to specify where to find it.
311 * When natively debugging programs on PowerPC BookE processors running
312 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
313 watchpoints, which specify a mask in addition to an address to watch.
314 The mask specifies that some bits of an address (the bits which are
315 reset in the mask) should be ignored when matching the address accessed
316 by the inferior against the watchpoint address. See the "PowerPC Embedded"
317 section in the user manual for more details.
319 * The new option --once causes GDBserver to stop listening for connections once
320 the first connection is made. The listening port used by GDBserver will
321 become available after that.
323 * New commands "info macros" and "alias" have been added.
325 * New function parameters suffix @entry specifies value of function parameter
326 at the time the function got called. Entry values are available only since
332 "!" is now an alias of the "shell" command.
333 Note that no space is needed between "!" and SHELL COMMAND.
337 watch EXPRESSION mask MASK_VALUE
338 The watch command now supports the mask argument which allows creation
339 of masked watchpoints, if the current architecture supports this feature.
341 info auto-load-scripts [REGEXP]
342 This command was formerly named "maintenance print section-scripts".
343 It is now generally useful and is no longer a maintenance-only command.
345 info macro [-all] [--] MACRO
346 The info macro command has new options `-all' and `--'. The first for
347 printing all definitions of a macro. The second for explicitly specifying
348 the end of arguments and the beginning of the macro name in case the macro
349 name starts with a hyphen.
351 collect[/s] EXPRESSIONS
352 The tracepoint collect command now takes an optional modifier "/s"
353 that directs it to dereference pointer-to-character types and
354 collect the bytes of memory up to a zero byte. The behavior is
355 similar to what you see when you use the regular print command on a
356 string. An optional integer following the "/s" sets a bound on the
357 number of bytes that will be collected.
360 The trace start command now interprets any supplied arguments as a
361 note to be recorded with the trace run, with an effect similar to
362 setting the variable trace-notes.
365 The trace stop command now interprets any arguments as a note to be
366 mentioned along with the tstatus report that the trace was stopped
367 with a command. The effect is similar to setting the variable
370 * Tracepoints can now be enabled and disabled at any time after a trace
371 experiment has been started using the standard "enable" and "disable"
372 commands. It is now possible to start a trace experiment with no enabled
373 tracepoints; GDB will display a warning, but will allow the experiment to
374 begin, assuming that tracepoints will be enabled as needed while the trace
377 * Fast tracepoints on 32-bit x86-architectures can now be placed at
378 locations with 4-byte instructions, when they were previously
379 limited to locations with instructions of 5 bytes or longer.
385 Set the GDB prompt, and allow escape sequences to be inserted to
386 display miscellaneous information (see 'help set extended-prompt'
387 for the list of sequences). This prompt (and any information
388 accessed through the escape sequences) is updated every time the
391 set print entry-values (both|compact|default|if-needed|no|only|preferred)
392 show print entry-values
393 Set printing of frame argument values at function entry. In some cases
394 GDB can determine the value of function argument which was passed by the
395 function caller, even if the value was modified inside the called function.
397 set debug entry-values
398 show debug entry-values
399 Control display of debugging info for determining frame argument values at
400 function entry and virtual tail call frames.
402 set basenames-may-differ
403 show basenames-may-differ
404 Set whether a source file may have multiple base names.
405 (A "base name" is the name of a file with the directory part removed.
406 Example: The base name of "/home/user/hello.c" is "hello.c".)
407 If set, GDB will canonicalize file names (e.g., expand symlinks)
408 before comparing them. Canonicalization is an expensive operation,
409 but it allows the same file be known by more than one base name.
410 If not set (the default), all source files are assumed to have just
411 one base name, and gdb will do file name comparisons more efficiently.
417 Set a user name and notes for the current and any future trace runs.
418 This is useful for long-running and/or disconnected traces, to
419 inform others (or yourself) as to who is running the trace, supply
420 contact information, or otherwise explain what is going on.
423 show trace-stop-notes
424 Set a note attached to the trace run, that is displayed when the
425 trace has been stopped by a tstop command. This is useful for
426 instance as an explanation, if you are stopping a trace run that was
427 started by someone else.
433 Dynamically enable a tracepoint in a started trace experiment.
437 Dynamically disable a tracepoint in a started trace experiment.
441 Set the user and notes of the trace run.
445 Query the current status of a tracepoint.
449 Query the minimum length of instruction at which a fast tracepoint may
452 * Dcache size (number of lines) and line-size are now runtime-configurable
453 via "set dcache line" and "set dcache line-size" commands.
457 Texas Instruments TMS320C6x tic6x-*-*
461 Renesas RL78 rl78-*-elf
463 *** Changes in GDB 7.3.1
465 * The build failure for NetBSD and OpenBSD targets have now been fixed.
467 *** Changes in GDB 7.3
469 * GDB has a new command: "thread find [REGEXP]".
470 It finds the thread id whose name, target id, or thread extra info
471 matches the given regular expression.
473 * The "catch syscall" command now works on mips*-linux* targets.
475 * The -data-disassemble MI command now supports modes 2 and 3 for
476 dumping the instruction opcodes.
478 * New command line options
480 -data-directory DIR Specify DIR as the "data-directory".
481 This is mostly for testing purposes.
483 * The "maint set python auto-load on|off" command has been renamed to
484 "set auto-load-scripts on|off".
486 * GDB has a new command: "set directories".
487 It is like the "dir" command except that it replaces the
488 source path list instead of augmenting it.
490 * GDB now understands thread names.
492 On GNU/Linux, "info threads" will display the thread name as set by
493 prctl or pthread_setname_np.
495 There is also a new command, "thread name", which can be used to
496 assign a name internally for GDB to display.
499 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
500 has been integrated into GDB.
504 ** The function gdb.Write now accepts an optional keyword 'stream'.
505 This keyword, when provided, will direct the output to either
506 stdout, stderr, or GDB's logging output.
508 ** Parameters can now be be sub-classed in Python, and in particular
509 you may implement the get_set_doc and get_show_doc functions.
510 This improves how Parameter set/show documentation is processed
511 and allows for more dynamic content.
513 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
514 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
515 have an is_valid method.
517 ** Breakpoints can now be sub-classed in Python, and in particular
518 you may implement a 'stop' function that is executed each time
519 the inferior reaches that breakpoint.
521 ** New function gdb.lookup_global_symbol looks up a global symbol.
523 ** GDB values in Python are now callable if the value represents a
524 function. For example, if 'some_value' represents a function that
525 takes two integer parameters and returns a value, you can call
526 that function like so:
528 result = some_value (10,20)
530 ** Module gdb.types has been added.
531 It contains a collection of utilities for working with gdb.Types objects:
532 get_basic_type, has_field, make_enum_dict.
534 ** Module gdb.printing has been added.
535 It contains utilities for writing and registering pretty-printers.
536 New classes: PrettyPrinter, SubPrettyPrinter,
537 RegexpCollectionPrettyPrinter.
538 New function: register_pretty_printer.
540 ** New commands "info pretty-printers", "enable pretty-printer" and
541 "disable pretty-printer" have been added.
543 ** gdb.parameter("directories") is now available.
545 ** New function gdb.newest_frame returns the newest frame in the
548 ** The gdb.InferiorThread class has a new "name" attribute. This
549 holds the thread's name.
551 ** Python Support for Inferior events.
552 Python scripts can add observers to be notified of events
553 occurring in the process being debugged.
554 The following events are currently supported:
555 - gdb.events.cont Continue event.
556 - gdb.events.exited Inferior exited event.
557 - gdb.events.stop Signal received, and Breakpoint hit events.
561 ** GDB now puts template parameters in scope when debugging in an
562 instantiation. For example, if you have:
564 template<int X> int func (void) { return X; }
566 then if you step into func<5>, "print X" will show "5". This
567 feature requires proper debuginfo support from the compiler; it
568 was added to GCC 4.5.
570 ** The motion commands "next", "finish", "until", and "advance" now
571 work better when exceptions are thrown. In particular, GDB will
572 no longer lose control of the inferior; instead, the GDB will
573 stop the inferior at the point at which the exception is caught.
574 This functionality requires a change in the exception handling
575 code that was introduced in GCC 4.5.
577 * GDB now follows GCC's rules on accessing volatile objects when
578 reading or writing target state during expression evaluation.
579 One notable difference to prior behavior is that "print x = 0"
580 no longer generates a read of x; the value of the assignment is
581 now always taken directly from the value being assigned.
583 * GDB now has some support for using labels in the program's source in
584 linespecs. For instance, you can use "advance label" to continue
585 execution to a label.
587 * GDB now has support for reading and writing a new .gdb_index
588 section. This section holds a fast index of DWARF debugging
589 information and can be used to greatly speed up GDB startup and
590 operation. See the documentation for `save gdb-index' for details.
592 * The "watch" command now accepts an optional "-location" argument.
593 When used, this causes GDB to watch the memory referred to by the
594 expression. Such a watchpoint is never deleted due to it going out
597 * GDB now supports thread debugging of core dumps on GNU/Linux.
599 GDB now activates thread debugging using the libthread_db library
600 when debugging GNU/Linux core dumps, similarly to when debugging
601 live processes. As a result, when debugging a core dump file, GDB
602 is now able to display pthread_t ids of threads. For example, "info
603 threads" shows the same output as when debugging the process when it
604 was live. In earlier releases, you'd see something like this:
607 * 1 LWP 6780 main () at main.c:10
609 While now you see this:
612 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
614 It is also now possible to inspect TLS variables when debugging core
617 When debugging a core dump generated on a machine other than the one
618 used to run GDB, you may need to point GDB at the correct
619 libthread_db library with the "set libthread-db-search-path"
620 command. See the user manual for more details on this command.
622 * When natively debugging programs on PowerPC BookE processors running
623 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
624 which stop execution of the inferior whenever it executes an instruction
625 at any address within the specified range. See the "PowerPC Embedded"
626 section in the user manual for more details.
628 * New features in the GDB remote stub, GDBserver
630 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
631 and i686 LynxOS (version 5.x).
633 ** GDBserver is now supported on Blackfin Linux.
635 * New native configurations
637 ia64 HP-UX ia64-*-hpux*
641 Analog Devices, Inc. Blackfin Processor bfin-*
643 * Ada task switching is now supported on sparc-elf targets when
644 debugging a program using the Ravenscar Profile. For more information,
645 see the "Tasking Support when using the Ravenscar Profile" section
646 in the GDB user manual.
648 * Guile support was removed.
650 * New features in the GNU simulator
652 ** The --map-info flag lists all known core mappings.
654 ** CFI flashes may be simulated via the "cfi" device.
656 *** Changes in GDB 7.2
658 * Shared library support for remote targets by default
660 When GDB is configured for a generic, non-OS specific target, like
661 for example, --target=arm-eabi or one of the many *-*-elf targets,
662 GDB now queries remote stubs for loaded shared libraries using the
663 `qXfer:libraries:read' packet. Previously, shared library support
664 was always disabled for such configurations.
668 ** Argument Dependent Lookup (ADL)
670 In C++ ADL lookup directs function search to the namespaces of its
671 arguments even if the namespace has not been imported.
681 Here the compiler will search for `foo' in the namespace of 'b'
682 and find A::foo. GDB now supports this. This construct is commonly
683 used in the Standard Template Library for operators.
685 ** Improved User Defined Operator Support
687 In addition to member operators, GDB now supports lookup of operators
688 defined in a namespace and imported with a `using' directive, operators
689 defined in the global scope, operators imported implicitly from an
690 anonymous namespace, and the ADL operators mentioned in the previous
692 GDB now also supports proper overload resolution for all the previously
693 mentioned flavors of operators.
695 ** static const class members
697 Printing of static const class members that are initialized in the
698 class definition has been fixed.
700 * Windows Thread Information Block access.
702 On Windows targets, GDB now supports displaying the Windows Thread
703 Information Block (TIB) structure. This structure is visible either
704 by using the new command `info w32 thread-information-block' or, by
705 dereferencing the new convenience variable named `$_tlb', a
706 thread-specific pointer to the TIB. This feature is also supported
707 when remote debugging using GDBserver.
711 Static tracepoints are calls in the user program into a tracing
712 library. One such library is a port of the LTTng kernel tracer to
713 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
714 When debugging with GDBserver, GDB now supports combining the GDB
715 tracepoint machinery with such libraries. For example: the user can
716 use GDB to probe a static tracepoint marker (a call from the user
717 program into the tracing library) with the new "strace" command (see
718 "New commands" below). This creates a "static tracepoint" in the
719 breakpoint list, that can be manipulated with the same feature set
720 as fast and regular tracepoints. E.g., collect registers, local and
721 global variables, collect trace state variables, and define
722 tracepoint conditions. In addition, the user can collect extra
723 static tracepoint marker specific data, by collecting the new
724 $_sdata internal variable. When analyzing the trace buffer, you can
725 inspect $_sdata like any other variable available to GDB. For more
726 information, see the "Tracepoints" chapter in GDB user manual. New
727 remote packets have been defined to support static tracepoints, see
728 the "New remote packets" section below.
730 * Better reconstruction of tracepoints after disconnected tracing
732 GDB will attempt to download the original source form of tracepoint
733 definitions when starting a trace run, and then will upload these
734 upon reconnection to the target, resulting in a more accurate
735 reconstruction of the tracepoints that are in use on the target.
739 You can now exercise direct control over the ways that GDB can
740 affect your program. For instance, you can disallow the setting of
741 breakpoints, so that the program can run continuously (assuming
742 non-stop mode). In addition, the "observer" variable is available
743 to switch all of the different controls; in observer mode, GDB
744 cannot affect the target's behavior at all, which is useful for
745 tasks like diagnosing live systems in the field.
747 * The new convenience variable $_thread holds the number of the
754 Return the address of the Windows Thread Information Block of a given thread.
758 In response to several of the tracepoint packets, the target may now
759 also respond with a number of intermediate `qRelocInsn' request
760 packets before the final result packet, to have GDB handle
761 relocating an instruction to execute at a different address. This
762 is particularly useful for stubs that support fast tracepoints. GDB
763 reports support for this feature in the qSupported packet.
767 List static tracepoint markers in the target program.
771 List static tracepoint markers at a given address in the target
774 qXfer:statictrace:read
776 Read the static trace data collected (by a `collect $_sdata'
777 tracepoint action). The remote stub reports support for this packet
778 to gdb's qSupported query.
782 Send the current settings of GDB's permission flags.
786 Send part of the source (textual) form of a tracepoint definition,
787 which includes location, conditional, and action list.
789 * The source command now accepts a -s option to force searching for the
790 script in the source search path even if the script name specifies
793 * New features in the GDB remote stub, GDBserver
795 - GDBserver now support tracepoints (including fast tracepoints, and
796 static tracepoints). The feature is currently supported by the
797 i386-linux and amd64-linux builds. See the "Tracepoints support
798 in gdbserver" section in the manual for more information.
800 GDBserver JIT compiles the tracepoint's conditional agent
801 expression bytecode into native code whenever possible for low
802 overhead dynamic tracepoints conditionals. For such tracepoints,
803 an expression that examines program state is evaluated when the
804 tracepoint is reached, in order to determine whether to capture
805 trace data. If the condition is simple and false, processing the
806 tracepoint finishes very quickly and no data is gathered.
808 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
809 for static tracepoints support.
811 - GDBserver now supports x86_64 Windows 64-bit debugging.
813 * GDB now sends xmlRegisters= in qSupported packet to indicate that
814 it understands register description.
816 * The --batch flag now disables pagination and queries.
818 * X86 general purpose registers
820 GDB now supports reading/writing byte, word and double-word x86
821 general purpose registers directly. This means you can use, say,
822 $ah or $ax to refer, respectively, to the byte register AH and
823 16-bit word register AX that are actually portions of the 32-bit
824 register EAX or 64-bit register RAX.
826 * The `commands' command now accepts a range of breakpoints to modify.
827 A plain `commands' following a command that creates multiple
828 breakpoints affects all the breakpoints set by that command. This
829 applies to breakpoints set by `rbreak', and also applies when a
830 single `break' command creates multiple breakpoints (e.g.,
831 breakpoints on overloaded c++ functions).
833 * The `rbreak' command now accepts a filename specification as part of
834 its argument, limiting the functions selected by the regex to those
835 in the specified file.
837 * Support for remote debugging Windows and SymbianOS shared libraries
838 from Unix hosts has been improved. Non Windows GDB builds now can
839 understand target reported file names that follow MS-DOS based file
840 system semantics, such as file names that include drive letters and
841 use the backslash character as directory separator. This makes it
842 possible to transparently use the "set sysroot" and "set
843 solib-search-path" on Unix hosts to point as host copies of the
844 target's shared libraries. See the new command "set
845 target-file-system-kind" described below, and the "Commands to
846 specify files" section in the user manual for more information.
850 eval template, expressions...
851 Convert the values of one or more expressions under the control
852 of the string template to a command line, and call it.
854 set target-file-system-kind unix|dos-based|auto
855 show target-file-system-kind
856 Set or show the assumed file system kind for target reported file
859 save breakpoints <filename>
860 Save all current breakpoint definitions to a file suitable for use
861 in a later debugging session. To read the saved breakpoint
862 definitions, use the `source' command.
864 `save tracepoints' is a new alias for `save-tracepoints'. The latter
867 info static-tracepoint-markers
868 Display information about static tracepoint markers in the target.
870 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
871 Define a static tracepoint by probing a marker at the given
872 function, line, address, or marker ID.
876 Enable and disable observer mode.
878 set may-write-registers on|off
879 set may-write-memory on|off
880 set may-insert-breakpoints on|off
881 set may-insert-tracepoints on|off
882 set may-insert-fast-tracepoints on|off
883 set may-interrupt on|off
884 Set individual permissions for GDB effects on the target. Note that
885 some of these settings can have undesirable or surprising
886 consequences, particularly when changed in the middle of a session.
887 For instance, disabling the writing of memory can prevent
888 breakpoints from being inserted, cause single-stepping to fail, or
889 even crash your program, if you disable after breakpoints have been
890 inserted. However, GDB should not crash.
892 set record memory-query on|off
893 show record memory-query
894 Control whether to stop the inferior if memory changes caused
895 by an instruction cannot be recorded.
900 The disassemble command now supports "start,+length" form of two arguments.
904 ** GDB now provides a new directory location, called the python directory,
905 where Python scripts written for GDB can be installed. The location
906 of that directory is <data-directory>/python, where <data-directory>
907 is the GDB data directory. For more details, see section `Scripting
908 GDB using Python' in the manual.
910 ** The GDB Python API now has access to breakpoints, symbols, symbol
911 tables, program spaces, inferiors, threads and frame's code blocks.
912 Additionally, GDB Parameters can now be created from the API, and
913 manipulated via set/show in the CLI.
915 ** New functions gdb.target_charset, gdb.target_wide_charset,
916 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
918 ** New exception gdb.GdbError.
920 ** Pretty-printers are now also looked up in the current program space.
922 ** Pretty-printers can now be individually enabled and disabled.
924 ** GDB now looks for names of Python scripts to auto-load in a
925 special section named `.debug_gdb_scripts', in addition to looking
926 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
928 * Tracepoint actions were unified with breakpoint commands. In particular,
929 there are no longer differences in "info break" output for breakpoints and
930 tracepoints and the "commands" command can be used for both tracepoints and
935 ARM Symbian arm*-*-symbianelf*
937 * D language support.
938 GDB now supports debugging programs written in the D programming
941 * GDB now supports the extended ptrace interface for PowerPC which is
942 available since Linux kernel version 2.6.34. This automatically enables
943 any hardware breakpoints and additional hardware watchpoints available in
944 the processor. The old ptrace interface exposes just one hardware
945 watchpoint and no hardware breakpoints.
947 * GDB is now able to use the Data Value Compare (DVC) register available on
948 embedded PowerPC processors to implement in hardware simple watchpoint
949 conditions of the form:
951 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
953 This works in native GDB running on Linux kernels with the extended ptrace
954 interface mentioned above.
956 *** Changes in GDB 7.1
962 GDB now supports importing of namespaces in C++. This enables the
963 user to inspect variables from imported namespaces. Support for
964 namepace aliasing has also been added. So, if a namespace is
965 aliased in the current scope (e.g. namepace C=A; ) the user can
966 print variables using the alias (e.g. (gdb) print C::x).
970 All known bugs relating to the printing of virtual base class were
971 fixed. It is now possible to call overloaded static methods using a
976 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
977 and reinterpret_cast<> are now handled by the C++ expression parser.
981 Xilinx MicroBlaze microblaze-*-*
986 Xilinx MicroBlaze microblaze
989 * Multi-program debugging.
991 GDB now has support for multi-program (a.k.a. multi-executable or
992 multi-exec) debugging. This allows for debugging multiple inferiors
993 simultaneously each running a different program under the same GDB
994 session. See "Debugging Multiple Inferiors and Programs" in the
995 manual for more information. This implied some user visible changes
996 in the multi-inferior support. For example, "info inferiors" now
997 lists inferiors that are not running yet or that have exited
998 already. See also "New commands" and "New options" below.
1000 * New tracing features
1002 GDB's tracepoint facility now includes several new features:
1004 ** Trace state variables
1006 GDB tracepoints now include support for trace state variables, which
1007 are variables managed by the target agent during a tracing
1008 experiment. They are useful for tracepoints that trigger each
1009 other, so for instance one tracepoint can count hits in a variable,
1010 and then a second tracepoint has a condition that is true when the
1011 count reaches a particular value. Trace state variables share the
1012 $-syntax of GDB convenience variables, and can appear in both
1013 tracepoint actions and condition expressions. Use the "tvariable"
1014 command to create, and "info tvariables" to view; see "Trace State
1015 Variables" in the manual for more detail.
1019 GDB now includes an option for defining fast tracepoints, which
1020 targets may implement more efficiently, such as by installing a jump
1021 into the target agent rather than a trap instruction. The resulting
1022 speedup can be by two orders of magnitude or more, although the
1023 tradeoff is that some program locations on some target architectures
1024 might not allow fast tracepoint installation, for instance if the
1025 instruction to be replaced is shorter than the jump. To request a
1026 fast tracepoint, use the "ftrace" command, with syntax identical to
1027 the regular trace command.
1029 ** Disconnected tracing
1031 It is now possible to detach GDB from the target while it is running
1032 a trace experiment, then reconnect later to see how the experiment
1033 is going. In addition, a new variable disconnected-tracing lets you
1034 tell the target agent whether to continue running a trace if the
1035 connection is lost unexpectedly.
1039 GDB now has the ability to save the trace buffer into a file, and
1040 then use that file as a target, similarly to you can do with
1041 corefiles. You can select trace frames, print data that was
1042 collected in them, and use tstatus to display the state of the
1043 tracing run at the moment that it was saved. To create a trace
1044 file, use "tsave <filename>", and to use it, do "target tfile
1047 ** Circular trace buffer
1049 You can ask the target agent to handle the trace buffer as a
1050 circular buffer, discarding the oldest trace frames to make room for
1051 newer ones, by setting circular-trace-buffer to on. This feature may
1052 not be available for all target agents.
1057 The disassemble command, when invoked with two arguments, now requires
1058 the arguments to be comma-separated.
1061 The info variables command now displays variable definitions. Files
1062 which only declare a variable are not shown.
1065 The source command is now capable of sourcing Python scripts.
1066 This feature is dependent on the debugger being build with Python
1069 Related to this enhancement is also the introduction of a new command
1070 "set script-extension" (see below).
1072 * New commands (for set/show, see "New options" below)
1074 record save [<FILENAME>]
1075 Save a file (in core file format) containing the process record
1076 execution log for replay debugging at a later time.
1078 record restore <FILENAME>
1079 Restore the process record execution log that was saved at an
1080 earlier time, for replay debugging.
1082 add-inferior [-copies <N>] [-exec <FILENAME>]
1085 clone-inferior [-copies <N>] [ID]
1086 Make a new inferior ready to execute the same program another
1087 inferior has loaded.
1092 maint info program-spaces
1093 List the program spaces loaded into GDB.
1095 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1096 show remote interrupt-sequence
1097 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1098 as the sequence to the remote target in order to interrupt the execution.
1099 Ctrl-C is a default. Some system prefers BREAK which is high level of
1100 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1101 Magic SysRq g. It is BREAK signal and character 'g'.
1103 set remote interrupt-on-connect [on | off]
1104 show remote interrupt-on-connect
1105 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1106 remote target when gdb connects to it. This is needed when you debug
1109 set remotebreak [on | off]
1111 Deprecated. Use "set/show remote interrupt-sequence" instead.
1113 tvariable $NAME [ = EXP ]
1114 Create or modify a trace state variable.
1117 List trace state variables and their values.
1119 delete tvariable $NAME ...
1120 Delete one or more trace state variables.
1123 Evaluate the given expressions without collecting anything into the
1124 trace buffer. (Valid in tracepoint actions only.)
1126 ftrace FN / FILE:LINE / *ADDR
1127 Define a fast tracepoint at the given function, line, or address.
1129 * New expression syntax
1131 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1132 GDB now parses 0b101010 identically with 42.
1136 set follow-exec-mode new|same
1137 show follow-exec-mode
1138 Control whether GDB reuses the same inferior across an exec call or
1139 creates a new one. This is useful to be able to restart the old
1140 executable after the inferior having done an exec call.
1142 set default-collect EXPR, ...
1143 show default-collect
1144 Define a list of expressions to be collected at each tracepoint.
1145 This is a useful way to ensure essential items are not overlooked,
1146 such as registers or a critical global variable.
1148 set disconnected-tracing
1149 show disconnected-tracing
1150 If set to 1, the target is instructed to continue tracing if it
1151 loses its connection to GDB. If 0, the target is to stop tracing
1154 set circular-trace-buffer
1155 show circular-trace-buffer
1156 If set to on, the target is instructed to use a circular trace buffer
1157 and discard the oldest trace frames instead of stopping the trace due
1158 to a full trace buffer. If set to off, the trace stops when the buffer
1159 fills up. Some targets may not support this.
1161 set script-extension off|soft|strict
1162 show script-extension
1163 If set to "off", the debugger does not perform any script language
1164 recognition, and all sourced files are assumed to be GDB scripts.
1165 If set to "soft" (the default), files are sourced according to
1166 filename extension, falling back to GDB scripts if the first
1168 If set to "strict", files are sourced according to filename extension.
1170 set ada trust-PAD-over-XVS on|off
1171 show ada trust-PAD-over-XVS
1172 If off, activate a workaround against a bug in the debugging information
1173 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1174 the GCC sources for more information about the GNAT encoding and
1175 PAD types in particular). It is always safe to set this option to
1176 off, but this introduces a slight performance penalty. The default
1179 * Python API Improvements
1181 ** GDB provides the new class gdb.LazyString. This is useful in
1182 some pretty-printing cases. The new method gdb.Value.lazy_string
1183 provides a simple way to create objects of this type.
1185 ** The fields returned by gdb.Type.fields now have an
1186 `is_base_class' attribute.
1188 ** The new method gdb.Type.range returns the range of an array type.
1190 ** The new method gdb.parse_and_eval can be used to parse and
1191 evaluate an expression.
1193 * New remote packets
1196 Define a trace state variable.
1199 Get the current value of a trace state variable.
1202 Set desired tracing behavior upon disconnection.
1205 Set the trace buffer to be linear or circular.
1208 Get data about the tracepoints currently in use.
1212 Process record now works correctly with hardware watchpoints.
1214 Multiple bug fixes have been made to the mips-irix port, making it
1215 much more reliable. In particular:
1216 - Debugging threaded applications is now possible again. Previously,
1217 GDB would hang while starting the program, or while waiting for
1218 the program to stop at a breakpoint.
1219 - Attaching to a running process no longer hangs.
1220 - An error occurring while loading a core file has been fixed.
1221 - Changing the value of the PC register now works again. This fixes
1222 problems observed when using the "jump" command, or when calling
1223 a function from GDB, or even when assigning a new value to $pc.
1224 - With the "finish" and "return" commands, the return value for functions
1225 returning a small array is now correctly printed.
1226 - It is now possible to break on shared library code which gets executed
1227 during a shared library init phase (code executed while executing
1228 their .init section). Previously, the breakpoint would have no effect.
1229 - GDB is now able to backtrace through the signal handler for
1230 non-threaded programs.
1232 PIE (Position Independent Executable) programs debugging is now supported.
1233 This includes debugging execution of PIC (Position Independent Code) shared
1234 libraries although for that, it should be possible to run such libraries as an
1237 *** Changes in GDB 7.0
1239 * GDB now has an interface for JIT compilation. Applications that
1240 dynamically generate code can create symbol files in memory and register
1241 them with GDB. For users, the feature should work transparently, and
1242 for JIT developers, the interface is documented in the GDB manual in the
1243 "JIT Compilation Interface" chapter.
1245 * Tracepoints may now be conditional. The syntax is as for
1246 breakpoints; either an "if" clause appended to the "trace" command,
1247 or the "condition" command is available. GDB sends the condition to
1248 the target for evaluation using the same bytecode format as is used
1249 for tracepoint actions.
1251 * The disassemble command now supports: an optional /r modifier, print the
1252 raw instructions in hex as well as in symbolic form, and an optional /m
1253 modifier to print mixed source+assembly.
1255 * Process record and replay
1257 In a architecture environment that supports ``process record and
1258 replay'', ``process record and replay'' target can record a log of
1259 the process execution, and replay it with both forward and reverse
1262 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1263 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1264 set execution-direction {forward|reverse}, for targets that support
1267 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1268 feature is available with a native GDB running on kernel version
1271 * GDB now has support for multi-byte and wide character sets on the
1272 target. Strings whose character type is wchar_t, char16_t, or
1273 char32_t are now correctly printed. GDB supports wide- and unicode-
1274 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1275 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1276 `printf'. This feature requires iconv to work properly; if your
1277 system does not have a working iconv, GDB can use GNU libiconv. See
1278 the installation instructions for more information.
1280 * GDB now supports automatic retrieval of shared library files from
1281 remote targets. To use this feature, specify a system root that begins
1282 with the `remote:' prefix, either via the `set sysroot' command or via
1283 the `--with-sysroot' configure-time option.
1285 * "info sharedlibrary" now takes an optional regex of libraries to show,
1286 and it now reports if a shared library has no debugging information.
1288 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1289 now complete on file names.
1291 * When completing in expressions, gdb will attempt to limit
1292 completions to allowable structure or union fields, where appropriate.
1293 For instance, consider:
1295 # struct example { int f1; double f2; };
1296 # struct example variable;
1299 If the user types TAB at the end of this command line, the available
1300 completions will be "f1" and "f2".
1302 * Inlined functions are now supported. They show up in backtraces, and
1303 the "step", "next", and "finish" commands handle them automatically.
1305 * GDB now supports the token-splicing (##) and stringification (#)
1306 operators when expanding macros. It also supports variable-arity
1309 * GDB now supports inspecting extra signal information, exported by
1310 the new $_siginfo convenience variable. The feature is currently
1311 implemented on linux ARM, i386 and amd64.
1313 * GDB can now display the VFP floating point registers and NEON vector
1314 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1315 can provide these registers (requires Linux 2.6.30 or later). Remote
1316 and simulator targets may also provide them.
1318 * New remote packets
1321 Search memory for a sequence of bytes.
1324 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1325 operation over reliable transport links. Use of this packet is
1326 controlled by the `set remote noack-packet' command.
1329 Kill the process with the specified process ID. Use this in preference
1330 to `k' when multiprocess protocol extensions are supported.
1333 Obtains additional operating system information
1337 Read or write additional signal information.
1339 * Removed remote protocol undocumented extension
1341 An undocumented extension to the remote protocol's `S' stop reply
1342 packet that permited the stub to pass a process id was removed.
1343 Remote servers should use the `T' stop reply packet instead.
1345 * GDB now supports multiple function calling conventions according to the
1346 DWARF-2 DW_AT_calling_convention function attribute.
1348 * The SH target utilizes the aforementioned change to distinguish between gcc
1349 and Renesas calling convention. It also adds the new CLI commands
1350 `set/show sh calling-convention'.
1352 * GDB can now read compressed debug sections, as produced by GNU gold
1353 with the --compress-debug-sections=zlib flag.
1355 * 64-bit core files are now supported on AIX.
1357 * Thread switching is now supported on Tru64.
1359 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1360 which will be allocated using malloc later in program execution.
1362 * The qXfer:libraries:read remote procotol packet now allows passing a
1363 list of section offsets.
1365 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1366 conditions handling signals delivered during attach or thread creation
1367 have also been fixed.
1369 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1370 From the user's standpoint, all unqualified instances of True and False
1371 are treated as the standard definitions, regardless of context.
1373 * GDB now parses C++ symbol and type names more flexibly. For
1376 template<typename T> class C { };
1379 GDB will now correctly handle all of:
1381 ptype C<char const *>
1382 ptype C<char const*>
1383 ptype C<const char *>
1384 ptype C<const char*>
1386 * New features in the GDB remote stub, gdbserver
1388 - The "--wrapper" command-line argument tells gdbserver to use a
1389 wrapper program to launch programs for debugging.
1391 - On PowerPC and S/390 targets, it is now possible to use a single
1392 gdbserver executable to debug both 32-bit and 64-bit programs.
1393 (This requires gdbserver itself to be built as a 64-bit executable.)
1395 - gdbserver uses the new noack protocol mode for TCP connections to
1396 reduce communications latency, if also supported and enabled in GDB.
1398 - Support for the sparc64-linux-gnu target is now included in
1401 - The amd64-linux build of gdbserver now supports debugging both
1402 32-bit and 64-bit programs.
1404 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1405 now support hardware watchpoints, and will use them automatically
1410 GDB now has support for scripting using Python. Whether this is
1411 available is determined at configure time.
1413 New GDB commands can now be written in Python.
1415 * Ada tasking support
1417 Ada tasks can now be inspected in GDB. The following commands have
1421 Print the list of Ada tasks.
1423 Print detailed information about task number N.
1425 Print the task number of the current task.
1427 Switch the context of debugging to task number N.
1429 * Support for user-defined prefixed commands. The "define" command can
1430 add new commands to existing prefixes, e.g. "target".
1432 * Multi-inferior, multi-process debugging.
1434 GDB now has generalized support for multi-inferior debugging. See
1435 "Debugging Multiple Inferiors" in the manual for more information.
1436 Although availability still depends on target support, the command
1437 set is more uniform now. The GNU/Linux specific multi-forks support
1438 has been migrated to this new framework. This implied some user
1439 visible changes; see "New commands" and also "Removed commands"
1442 * Target descriptions can now describe the target OS ABI. See the
1443 "Target Description Format" section in the user manual for more
1446 * Target descriptions can now describe "compatible" architectures
1447 to indicate that the target can execute applications for a different
1448 architecture in addition to those for the main target architecture.
1449 See the "Target Description Format" section in the user manual for
1452 * Multi-architecture debugging.
1454 GDB now includes general supports for debugging applications on
1455 hybrid systems that use more than one single processor architecture
1456 at the same time. Each such hybrid architecture still requires
1457 specific support to be added. The only hybrid architecture supported
1458 in this version of GDB is the Cell Broadband Engine.
1460 * GDB now supports integrated debugging of Cell/B.E. applications that
1461 use both the PPU and SPU architectures. To enable support for hybrid
1462 Cell/B.E. debugging, you need to configure GDB to support both the
1463 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1464 --enable-targets configure option.
1466 * Non-stop mode debugging.
1468 For some targets, GDB now supports an optional mode of operation in
1469 which you can examine stopped threads while other threads continue
1470 to execute freely. This is referred to as non-stop mode, with the
1471 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1472 section in the user manual for more information.
1474 To be able to support remote non-stop debugging, a remote stub needs
1475 to implement the non-stop mode remote protocol extensions, as
1476 described in the "Remote Non-Stop" section of the user manual. The
1477 GDB remote stub, gdbserver, has been adjusted to support these
1478 extensions on linux targets.
1480 * New commands (for set/show, see "New options" below)
1482 catch syscall [NAME(S) | NUMBER(S)]
1483 Catch system calls. Arguments, which should be names of system
1484 calls or their numbers, mean catch only those syscalls. Without
1485 arguments, every syscall will be caught. When the inferior issues
1486 any of the specified syscalls, GDB will stop and announce the system
1487 call, both when it is called and when its call returns. This
1488 feature is currently available with a native GDB running on the
1489 Linux Kernel, under the following architectures: x86, x86_64,
1490 PowerPC and PowerPC64.
1492 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1494 Search memory for a sequence of bytes.
1496 maint set python print-stack
1497 maint show python print-stack
1498 Show a stack trace when an error is encountered in a Python script.
1501 Invoke CODE by passing it to the Python interpreter.
1506 These allow macros to be defined, undefined, and listed
1510 Show operating system information about processes.
1513 List the inferiors currently under GDB's control.
1516 Switch focus to inferior number NUM.
1519 Detach from inferior number NUM.
1522 Kill inferior number NUM.
1526 set spu stop-on-load
1527 show spu stop-on-load
1528 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1530 set spu auto-flush-cache
1531 show spu auto-flush-cache
1532 Control whether to automatically flush the software-managed cache
1533 during Cell/B.E. debugging.
1535 set sh calling-convention
1536 show sh calling-convention
1537 Control the calling convention used when calling SH target functions.
1540 show debug timestamp
1541 Control display of timestamps with GDB debugging output.
1543 set disassemble-next-line
1544 show disassemble-next-line
1545 Control display of disassembled source lines or instructions when
1548 set remote noack-packet
1549 show remote noack-packet
1550 Set/show the use of remote protocol QStartNoAckMode packet. See above
1551 under "New remote packets."
1553 set remote query-attached-packet
1554 show remote query-attached-packet
1555 Control use of remote protocol `qAttached' (query-attached) packet.
1557 set remote read-siginfo-object
1558 show remote read-siginfo-object
1559 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1562 set remote write-siginfo-object
1563 show remote write-siginfo-object
1564 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1567 set remote reverse-continue
1568 show remote reverse-continue
1569 Control use of remote protocol 'bc' (reverse-continue) packet.
1571 set remote reverse-step
1572 show remote reverse-step
1573 Control use of remote protocol 'bs' (reverse-step) packet.
1575 set displaced-stepping
1576 show displaced-stepping
1577 Control displaced stepping mode. Displaced stepping is a way to
1578 single-step over breakpoints without removing them from the debuggee.
1579 Also known as "out-of-line single-stepping".
1582 show debug displaced
1583 Control display of debugging info for displaced stepping.
1585 maint set internal-error
1586 maint show internal-error
1587 Control what GDB does when an internal error is detected.
1589 maint set internal-warning
1590 maint show internal-warning
1591 Control what GDB does when an internal warning is detected.
1596 Use a wrapper program to launch programs for debugging.
1598 set multiple-symbols (all|ask|cancel)
1599 show multiple-symbols
1600 The value of this variable can be changed to adjust the debugger behavior
1601 when an expression or a breakpoint location contains an ambiguous symbol
1602 name (an overloaded function name, for instance).
1604 set breakpoint always-inserted
1605 show breakpoint always-inserted
1606 Keep breakpoints always inserted in the target, as opposed to inserting
1607 them when resuming the target, and removing them when the target stops.
1608 This option can improve debugger performance on slow remote targets.
1610 set arm fallback-mode (arm|thumb|auto)
1611 show arm fallback-mode
1612 set arm force-mode (arm|thumb|auto)
1614 These commands control how ARM GDB determines whether instructions
1615 are ARM or Thumb. The default for both settings is auto, which uses
1616 the current CPSR value for instructions without symbols; previous
1617 versions of GDB behaved as if "set arm fallback-mode arm".
1619 set disable-randomization
1620 show disable-randomization
1621 Standalone programs run with the virtual address space randomization enabled
1622 by default on some platforms. This option keeps the addresses stable across
1623 multiple debugging sessions.
1627 Control whether other threads are stopped or not when some thread hits
1632 Requests that asynchronous execution is enabled in the target, if available.
1633 In this case, it's possible to resume target in the background, and interact
1634 with GDB while the target is running. "show target-async" displays the
1635 current state of asynchronous execution of the target.
1637 set target-wide-charset
1638 show target-wide-charset
1639 The target-wide-charset is the name of the character set that GDB
1640 uses when printing characters whose type is wchar_t.
1642 set tcp auto-retry (on|off)
1644 set tcp connect-timeout
1645 show tcp connect-timeout
1646 These commands allow GDB to retry failed TCP connections to a remote stub
1647 with a specified timeout period; this is useful if the stub is launched
1648 in parallel with GDB but may not be ready to accept connections immediately.
1650 set libthread-db-search-path
1651 show libthread-db-search-path
1652 Control list of directories which GDB will search for appropriate
1655 set schedule-multiple (on|off)
1656 show schedule-multiple
1657 Allow GDB to resume all threads of all processes or only threads of
1658 the current process.
1662 Use more aggressive caching for accesses to the stack. This improves
1663 performance of remote debugging (particularly backtraces) without
1664 affecting correctness.
1666 set interactive-mode (on|off|auto)
1667 show interactive-mode
1668 Control whether GDB runs in interactive mode (on) or not (off).
1669 When in interactive mode, GDB waits for the user to answer all
1670 queries. Otherwise, GDB does not wait and assumes the default
1671 answer. When set to auto (the default), GDB determines which
1672 mode to use based on the stdin settings.
1677 For program forks, this is replaced by the new more generic `info
1678 inferiors' command. To list checkpoints, you can still use the
1679 `info checkpoints' command, which was an alias for the `info forks'
1683 Replaced by the new `inferior' command. To switch between
1684 checkpoints, you can still use the `restart' command, which was an
1685 alias for the `fork' command.
1688 This is removed, since some targets don't have a notion of
1689 processes. To switch between processes, you can still use the
1690 `inferior' command using GDB's own inferior number.
1693 For program forks, this is replaced by the new more generic `kill
1694 inferior' command. To delete a checkpoint, you can still use the
1695 `delete checkpoint' command, which was an alias for the `delete
1699 For program forks, this is replaced by the new more generic `detach
1700 inferior' command. To detach a checkpoint, you can still use the
1701 `detach checkpoint' command, which was an alias for the `detach
1704 * New native configurations
1706 x86/x86_64 Darwin i[34567]86-*-darwin*
1708 x86_64 MinGW x86_64-*-mingw*
1712 Lattice Mico32 lm32-*
1713 x86 DICOS i[34567]86-*-dicos*
1714 x86_64 DICOS x86_64-*-dicos*
1717 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1718 (mingw32ce) debugging.
1724 These commands were actually not implemented on any target.
1726 *** Changes in GDB 6.8
1728 * New native configurations
1730 NetBSD/hppa hppa*-*netbsd*
1731 Xtensa GNU/Linux xtensa*-*-linux*
1735 NetBSD/hppa hppa*-*-netbsd*
1736 Xtensa GNU/Lunux xtensa*-*-linux*
1738 * Change in command line behavior -- corefiles vs. process ids.
1740 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1741 attaching to process NUMBER fails, GDB no longer attempts to open a
1742 core file named NUMBER. Attaching to a program using the -c option
1743 is no longer supported. Instead, use the '-p' or '--pid' options.
1745 * GDB can now be built as a native debugger for debugging Windows x86
1746 (mingw32) Portable Executable (PE) programs.
1748 * Pending breakpoints no longer change their number when their address
1751 * GDB now supports breakpoints with multiple locations,
1752 including breakpoints on C++ constructors, inside C++ templates,
1753 and in inlined functions.
1755 * GDB's ability to debug optimized code has been improved. GDB more
1756 accurately identifies function bodies and lexical blocks that occupy
1757 more than one contiguous range of addresses.
1759 * Target descriptions can now describe registers for PowerPC.
1761 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1762 registers on PowerPC targets.
1764 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1765 targets even when the libthread_db library is not available.
1767 * The GDB remote stub, gdbserver, now supports the new file transfer
1768 commands (remote put, remote get, and remote delete).
1770 * The GDB remote stub, gdbserver, now supports run and attach in
1771 extended-remote mode.
1773 * hppa*64*-*-hpux11* target broken
1774 The debugger is unable to start a program and fails with the following
1775 error: "Error trying to get information about dynamic linker".
1776 The gdb-6.7 release is also affected.
1778 * GDB now supports the --enable-targets= configure option to allow
1779 building a single GDB executable that supports multiple remote
1780 target architectures.
1782 * GDB now supports debugging C and C++ programs which use the
1783 Decimal Floating Point extension. In addition, the PowerPC target
1784 now has a set of pseudo-registers to inspect decimal float values
1785 stored in two consecutive float registers.
1787 * The -break-insert MI command can optionally create pending
1790 * Improved support for debugging Ada
1791 Many improvements to the Ada language support have been made. These
1793 - Better support for Ada2005 interface types
1794 - Improved handling of arrays and slices in general
1795 - Better support for Taft-amendment types
1796 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1798 - Improved command completion in Ada
1801 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1806 set print frame-arguments (all|scalars|none)
1807 show print frame-arguments
1808 The value of this variable can be changed to control which argument
1809 values should be printed by the debugger when displaying a frame.
1814 Transfer files to and from a remote target, and delete remote files.
1821 Transfer files to and from a remote target, and delete remote files.
1823 * New remote packets
1830 Open, close, read, write, and delete files on the remote system.
1833 Attach to an existing process on the remote system, in extended-remote
1837 Run a new process on the remote system, in extended-remote mode.
1839 *** Changes in GDB 6.7
1841 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1842 bfd, libiberty and opcodes, as revealed by static analysis donated by
1843 Coverity, Inc. (http://scan.coverity.com).
1845 * When looking up multiply-defined global symbols, GDB will now prefer the
1846 symbol definition in the current shared library if it was built using the
1847 -Bsymbolic linker option.
1849 * When the Text User Interface (TUI) is not configured, GDB will now
1850 recognize the -tui command-line option and print a message that the TUI
1853 * The GDB remote stub, gdbserver, now has lower overhead for high
1854 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1856 * GDB for MIPS targets now autodetects whether a remote target provides
1857 32-bit or 64-bit register values.
1859 * Support for C++ member pointers has been improved.
1861 * GDB now understands XML target descriptions, which specify the
1862 target's overall architecture. GDB can read a description from
1863 a local file or over the remote serial protocol.
1865 * Vectors of single-byte data use a new integer type which is not
1866 automatically displayed as character or string data.
1868 * The /s format now works with the print command. It displays
1869 arrays of single-byte integers and pointers to single-byte integers
1872 * Target descriptions can now describe target-specific registers,
1873 for architectures which have implemented the support (currently
1874 only ARM, M68K, and MIPS).
1876 * GDB and the GDB remote stub, gdbserver, now support the XScale
1879 * The GDB remote stub, gdbserver, has been updated to support
1880 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1881 has been rewritten to use the standard GDB remote protocol.
1883 * GDB can now step into C++ functions which are called through thunks.
1885 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1887 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1888 layout. It also supports a TextSeg= and DataSeg= response when only
1889 segment base addresses (rather than offsets) are available.
1891 * The /i format now outputs any trailing branch delay slot instructions
1892 immediately following the last instruction within the count specified.
1894 * The GDB remote protocol "T" stop reply packet now supports a
1895 "library" response. Combined with the new "qXfer:libraries:read"
1896 packet, this response allows GDB to debug shared libraries on targets
1897 where the operating system manages the list of loaded libraries (e.g.
1898 Windows and SymbianOS).
1900 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1901 (DLLs) on Windows and Windows CE targets.
1903 * GDB now supports a faster verification that a .debug file matches its binary
1904 according to its build-id signature, if the signature is present.
1910 Enable or disable hardware flow control (RTS/CTS) on the serial port
1911 when debugging using remote targets.
1913 set mem inaccessible-by-default
1914 show mem inaccessible-by-default
1915 If the target supplies a memory map, for instance via the remote
1916 protocol's "qXfer:memory-map:read" packet, setting this variable
1917 prevents GDB from accessing memory outside the memory map. This
1918 is useful for targets with memory mapped registers or which react
1919 badly to accesses of unmapped address space.
1921 set breakpoint auto-hw
1922 show breakpoint auto-hw
1923 If the target supplies a memory map, for instance via the remote
1924 protocol's "qXfer:memory-map:read" packet, setting this variable
1925 lets GDB use hardware breakpoints automatically for memory regions
1926 where it can not use software breakpoints. This covers both the
1927 "break" command and internal breakpoints used for other commands
1928 including "next" and "finish".
1931 catch exception unhandled
1932 Stop the program execution when Ada exceptions are raised.
1935 Stop the program execution when an Ada assertion failed.
1939 Set an alternate system root for target files. This is a more
1940 general version of "set solib-absolute-prefix", which is now
1941 an alias to "set sysroot".
1944 Provide extended SPU facility status information. This set of
1945 commands is available only when debugging the Cell/B.E. SPU
1948 * New native configurations
1950 OpenBSD/sh sh*-*openbsd*
1953 unset tdesc filename
1955 Use the specified local file as an XML target description, and do
1956 not query the target for its built-in description.
1960 OpenBSD/sh sh*-*-openbsd*
1961 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1962 Toshiba Media Processor mep-elf
1964 * New remote packets
1967 Ignore the specified signals; pass them directly to the debugged program
1968 without stopping other threads or reporting them to GDB.
1970 qXfer:features:read:
1971 Read an XML target description from the target, which describes its
1976 Read or write contents of an spufs file on the target system. These
1977 packets are available only on the Cell/B.E. SPU architecture.
1979 qXfer:libraries:read:
1980 Report the loaded shared libraries. Combined with new "T" packet
1981 response, this packet allows GDB to debug shared libraries on
1982 targets where the operating system manages the list of loaded
1983 libraries (e.g. Windows and SymbianOS).
1987 Support for these obsolete configurations has been removed.
1995 i[34567]86-*-lynxos*
1996 i[34567]86-*-netware*
1997 i[34567]86-*-sco3.2v5*
1998 i[34567]86-*-sco3.2v4*
2000 i[34567]86-*-sysv4.2*
2003 i[34567]86-*-unixware2*
2004 i[34567]86-*-unixware*
2013 * Other removed features
2020 Various m68k-only ROM monitors.
2027 Various Renesas ROM monitors and debugging interfaces for SH and
2032 Support for a Macraigor serial interface to on-chip debugging.
2033 GDB does not directly support the newer parallel or USB
2038 A debug information format. The predecessor to DWARF 2 and
2039 DWARF 3, which are still supported.
2041 Support for the HP aCC compiler on HP-UX/PA-RISC
2043 SOM-encapsulated symbolic debugging information, automatic
2044 invocation of pxdb, and the aCC custom C++ ABI. This does not
2045 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2046 with aCC can still be debugged on an assembly level.
2048 MIPS ".pdr" sections
2050 A MIPS-specific format used to describe stack frame layout
2051 in debugging information.
2055 GDB could work with an older version of Guile to debug
2056 the interpreter and Scheme programs running in it.
2058 set mips stack-arg-size
2059 set mips saved-gpreg-size
2061 Use "set mips abi" to control parameter passing for MIPS.
2063 *** Changes in GDB 6.6
2068 Cell Broadband Engine SPU spu-elf
2070 * GDB can now be configured as a cross-debugger targeting native Windows
2071 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2072 running on a Windows system over TCP/IP to debug Windows programs.
2074 * The GDB remote stub, gdbserver, has been updated to support Windows and
2075 Cygwin debugging. Both single-threaded and multi-threaded programs are
2078 * The "set trust-readonly-sections" command works again. This command was
2079 broken in GDB 6.3, 6.4, and 6.5.
2081 * The "load" command now supports writing to flash memory, if the remote
2082 stub provides the required support.
2084 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2085 longer requires symbolic debug information (e.g. DWARF-2).
2090 unset substitute-path
2091 show substitute-path
2092 Manage a list of substitution rules that GDB uses to rewrite the name
2093 of the directories where the sources are located. This can be useful
2094 for instance when the sources were moved to a different location
2095 between compilation and debugging.
2099 Print each CLI command as it is executed. Each command is prefixed with
2100 a number of `+' symbols representing the nesting depth.
2101 The source command now has a `-v' option to enable the same feature.
2105 The ARM Demon monitor support (RDP protocol, "target rdp").
2107 Kernel Object Display, an embedded debugging feature which only worked with
2108 an obsolete version of Cisco IOS.
2110 The 'set download-write-size' and 'show download-write-size' commands.
2112 * New remote packets
2115 Tell a stub about GDB client features, and request remote target features.
2116 The first feature implemented is PacketSize, which allows the target to
2117 specify the size of packets it can handle - to minimize the number of
2118 packets required and improve performance when connected to a remote
2122 Fetch an OS auxilliary vector from the remote stub. This packet is a
2123 more efficient replacement for qPart:auxv:read.
2125 qXfer:memory-map:read:
2126 Fetch a memory map from the remote stub, including information about
2127 RAM, ROM, and flash memory devices.
2132 Erase and program a flash memory device.
2134 * Removed remote packets
2137 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2138 used it, and only gdbserver implemented it.
2140 *** Changes in GDB 6.5
2144 Renesas M32C/M16C m32c-elf
2146 Morpho Technologies ms1 ms1-elf
2150 init-if-undefined Initialize a convenience variable, but
2151 only if it doesn't already have a value.
2153 The following commands are presently only implemented for native GNU/Linux:
2155 checkpoint Save a snapshot of the program state.
2157 restart <n> Return the program state to a
2158 previously saved state.
2160 info checkpoints List currently saved checkpoints.
2162 delete-checkpoint <n> Delete a previously saved checkpoint.
2164 set|show detach-on-fork Tell gdb whether to detach from a newly
2165 forked process, or to keep debugging it.
2167 info forks List forks of the user program that
2168 are available to be debugged.
2170 fork <n> Switch to debugging one of several
2171 forks of the user program that are
2172 available to be debugged.
2174 delete-fork <n> Delete a fork from the list of forks
2175 that are available to be debugged (and
2176 kill the forked process).
2178 detach-fork <n> Delete a fork from the list of forks
2179 that are available to be debugged (and
2180 allow the process to continue).
2184 Morpho Technologies ms2 ms1-elf
2186 * Improved Windows host support
2188 GDB now builds as a cross debugger hosted on i686-mingw32, including
2189 native console support, and remote communications using either
2190 network sockets or serial ports.
2192 * Improved Modula-2 language support
2194 GDB can now print most types in the Modula-2 syntax. This includes:
2195 basic types, set types, record types, enumerated types, range types,
2196 pointer types and ARRAY types. Procedure var parameters are correctly
2197 printed and hexadecimal addresses and character constants are also
2198 written in the Modula-2 syntax. Best results can be obtained by using
2199 GNU Modula-2 together with the -gdwarf-2 command line option.
2203 The ARM rdi-share module.
2205 The Netware NLM debug server.
2207 *** Changes in GDB 6.4
2209 * New native configurations
2211 OpenBSD/arm arm*-*-openbsd*
2212 OpenBSD/mips64 mips64-*-openbsd*
2216 Morpho Technologies ms1 ms1-elf
2218 * New command line options
2220 --batch-silent As for --batch, but totally silent.
2221 --return-child-result The debugger will exist with the same value
2222 the child (debugged) program exited with.
2223 --eval-command COMMAND, -ex COMMAND
2224 Execute a single GDB CLI command. This may be
2225 specified multiple times and in conjunction
2226 with the --command (-x) option.
2228 * Deprecated commands removed
2230 The following commands, that were deprecated in 2000, have been
2234 set|show arm disassembly-flavor set|show arm disassembler
2235 othernames set arm disassembler
2236 set|show remotedebug set|show debug remote
2237 set|show archdebug set|show debug arch
2238 set|show eventdebug set|show debug event
2241 * New BSD user-level threads support
2243 It is now possible to debug programs using the user-level threads
2244 library on OpenBSD and FreeBSD. Currently supported (target)
2247 FreeBSD/amd64 x86_64-*-freebsd*
2248 FreeBSD/i386 i386-*-freebsd*
2249 OpenBSD/i386 i386-*-openbsd*
2251 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2252 are not yet supported.
2254 * New support for Matsushita MN10300 w/sim added
2255 (Work in progress). mn10300-elf.
2257 * REMOVED configurations and files
2259 VxWorks and the XDR protocol *-*-vxworks
2260 Motorola MCORE mcore-*-*
2261 National Semiconductor NS32000 ns32k-*-*
2263 * New "set print array-indexes" command
2265 After turning this setting "on", GDB prints the index of each element
2266 when displaying arrays. The default is "off" to preserve the previous
2269 * VAX floating point support
2271 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2273 * User-defined command support
2275 In addition to using $arg0..$arg9 for argument passing, it is now possible
2276 to use $argc to determine now many arguments have been passed. See the
2277 section on user-defined commands in the user manual for more information.
2279 *** Changes in GDB 6.3:
2281 * New command line option
2283 GDB now accepts -l followed by a number to set the timeout for remote
2286 * GDB works with GCC -feliminate-dwarf2-dups
2288 GDB now supports a more compact representation of DWARF-2 debug
2289 information using DW_FORM_ref_addr references. These are produced
2290 by GCC with the option -feliminate-dwarf2-dups and also by some
2291 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2292 to use -feliminate-dwarf2-dups.
2294 * Internationalization
2296 When supported by the host system, GDB will be built with
2297 internationalization (libintl). The task of marking up the sources is
2298 continued, we're looking forward to our first translation.
2302 Initial support for debugging programs compiled with the GNAT
2303 implementation of the Ada programming language has been integrated
2304 into GDB. In this release, support is limited to expression evaluation.
2306 * New native configurations
2308 GNU/Linux/m32r m32r-*-linux-gnu
2312 GDB's remote protocol now includes support for the 'p' packet. This
2313 packet is used to fetch individual registers from a remote inferior.
2315 * END-OF-LIFE registers[] compatibility module
2317 GDB's internal register infrastructure has been completely rewritten.
2318 The new infrastructure making possible the implementation of key new
2319 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2322 GDB 6.3 will be the last release to include the the registers[]
2323 compatibility module that allowed out-of-date configurations to
2324 continue to work. This change directly impacts the following
2334 powerpc bdm protocol
2336 Unless there is activity to revive these configurations, they will be
2337 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2339 * OBSOLETE configurations and files
2341 Configurations that have been declared obsolete in this release have
2342 been commented out. Unless there is activity to revive these
2343 configurations, the next release of GDB will have their sources
2344 permanently REMOVED.
2353 *** Changes in GDB 6.2.1:
2355 * MIPS `break main; run' gave an heuristic-fence-post warning
2357 When attempting to run even a simple program, a warning about
2358 heuristic-fence-post being hit would be reported. This problem has
2361 * MIPS IRIX 'long double' crashed GDB
2363 When examining a long double variable, GDB would get a segmentation
2364 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2365 IRIX long double values).
2369 A bug in the VAX stack code was causing problems with the "next"
2370 command. This problem has been fixed.
2372 *** Changes in GDB 6.2:
2374 * Fix for ``many threads''
2376 On GNU/Linux systems that use the NPTL threads library, a program
2377 rapidly creating and deleting threads would confuse GDB leading to the
2380 ptrace: No such process.
2381 thread_db_get_info: cannot get thread info: generic error
2383 This problem has been fixed.
2385 * "-async" and "-noasync" options removed.
2387 Support for the broken "-noasync" option has been removed (it caused
2390 * New ``start'' command.
2392 This command runs the program until the begining of the main procedure.
2394 * New BSD Kernel Data Access Library (libkvm) interface
2396 Using ``target kvm'' it is now possible to debug kernel core dumps and
2397 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2398 platforms. Currently supported (native-only) configurations are:
2400 FreeBSD/amd64 x86_64-*-freebsd*
2401 FreeBSD/i386 i?86-*-freebsd*
2402 NetBSD/i386 i?86-*-netbsd*
2403 NetBSD/m68k m68*-*-netbsd*
2404 NetBSD/sparc sparc-*-netbsd*
2405 OpenBSD/amd64 x86_64-*-openbsd*
2406 OpenBSD/i386 i?86-*-openbsd*
2407 OpenBSD/m68k m68*-openbsd*
2408 OpenBSD/sparc sparc-*-openbsd*
2410 * Signal trampoline code overhauled
2412 Many generic problems with GDB's signal handling code have been fixed.
2413 These include: backtraces through non-contiguous stacks; recognition
2414 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2415 call; backtrace through a signal trampoline; step into and out of
2416 signal handlers; and single-stepping in the signal trampoline.
2418 Please note that kernel bugs are a limiting factor here. These
2419 features have been shown to work on an s390 GNU/Linux system that
2420 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2422 * Cygwin support for DWARF 2 added.
2424 * New native configurations
2426 GNU/Linux/hppa hppa*-*-linux*
2427 OpenBSD/hppa hppa*-*-openbsd*
2428 OpenBSD/m68k m68*-*-openbsd*
2429 OpenBSD/m88k m88*-*-openbsd*
2430 OpenBSD/powerpc powerpc-*-openbsd*
2431 NetBSD/vax vax-*-netbsd*
2432 OpenBSD/vax vax-*-openbsd*
2434 * END-OF-LIFE frame compatibility module
2436 GDB's internal frame infrastructure has been completely rewritten.
2437 The new infrastructure making it possible to support key new features
2438 including DWARF 2 Call Frame Information. To aid in the task of
2439 migrating old configurations to this new infrastructure, a
2440 compatibility module, that allowed old configurations to continue to
2441 work, was also included.
2443 GDB 6.2 will be the last release to include this frame compatibility
2444 module. This change directly impacts the following configurations:
2454 Unless there is activity to revive these configurations, they will be
2455 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2457 * REMOVED configurations and files
2459 Sun 3, running SunOS 3 m68*-*-sunos3*
2460 Sun 3, running SunOS 4 m68*-*-sunos4*
2461 Sun 2, running SunOS 3 m68000-*-sunos3*
2462 Sun 2, running SunOS 4 m68000-*-sunos4*
2463 Motorola 680x0 running LynxOS m68*-*-lynxos*
2464 AT&T 3b1/Unix pc m68*-att-*
2465 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2466 decstation mips-dec-* mips-little-*
2467 riscos mips-*-riscos* mips-*-sysv*
2468 sonymips mips-sony-*
2469 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2471 *** Changes in GDB 6.1.1:
2473 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2475 The TUI (Text-mode User Interface) is now built as part of a default
2476 GDB configuration. It is enabled by either selecting the TUI with the
2477 command line option "-i=tui" or by running the separate "gdbtui"
2478 program. For more information on the TUI, see the manual "Debugging
2481 * Pending breakpoint support (also included in GDB 6.1)
2483 Support has been added to allow you to specify breakpoints in shared
2484 libraries that have not yet been loaded. If a breakpoint location
2485 cannot be found, and the "breakpoint pending" option is set to auto,
2486 GDB queries you if you wish to make the breakpoint pending on a future
2487 shared-library load. If and when GDB resolves the breakpoint symbol,
2488 the pending breakpoint is removed as one or more regular breakpoints
2491 Pending breakpoints are very useful for GCJ Java debugging.
2493 * Fixed ISO-C build problems
2495 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2496 non ISO-C code that stopped them being built using a more strict ISO-C
2497 compiler (e.g., IBM's C compiler).
2499 * Fixed build problem on IRIX 5
2501 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2502 wasn't able to compile compile on an IRIX 5 system.
2504 * Added execute permission to gdb/gdbserver/configure
2506 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2507 permission. This bug would cause configure to fail on a number of
2508 systems (Solaris, IRIX). Ref: server/519.
2510 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2512 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2513 has been updated to use constant array sizes.
2515 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2517 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2518 its generated DWARF Call Frame Info. This encoding was causing GDB to
2519 panic, that panic has been fixed. Ref: gdb/1628.
2521 * Fixed a problem when examining parameters in shared library code.
2523 When examining parameters in optimized shared library code generated
2524 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2525 not available''. GDB now correctly displays the variable's value.
2527 *** Changes in GDB 6.1:
2529 * Removed --with-mmalloc
2531 Support for the mmalloc memory manager has been removed, as it
2532 conflicted with the internal gdb byte cache.
2534 * Changes in AMD64 configurations
2536 The AMD64 target now includes the %cs and %ss registers. As a result
2537 the AMD64 remote protocol has changed; this affects the floating-point
2538 and SSE registers. If you rely on those registers for your debugging,
2539 you should upgrade gdbserver on the remote side.
2541 * Revised SPARC target
2543 The SPARC target has been completely revised, incorporating the
2544 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2545 support for LynxOS and SunOS 4 has been dropped. Calling functions
2546 from within GDB on operating systems with a non-executable stack
2547 (Solaris, OpenBSD) now works.
2551 GDB has a new C++ demangler which does a better job on the mangled
2552 names generated by current versions of g++. It also runs faster, so
2553 with this and other changes gdb should now start faster on large C++
2556 * DWARF 2 Location Expressions
2558 GDB support for location expressions has been extended to support function
2559 arguments and frame bases. Older versions of GDB could crash when they
2562 * C++ nested types and namespaces
2564 GDB's support for nested types and namespaces in C++ has been
2565 improved, especially if you use the DWARF 2 debugging format. (This
2566 is the default for recent versions of GCC on most platforms.)
2567 Specifically, if you have a class "Inner" defined within a class or
2568 namespace "Outer", then GDB realizes that the class's name is
2569 "Outer::Inner", not simply "Inner". This should greatly reduce the
2570 frequency of complaints about not finding RTTI symbols. In addition,
2571 if you are stopped at inside of a function defined within a namespace,
2572 GDB modifies its name lookup accordingly.
2574 * New native configurations
2576 NetBSD/amd64 x86_64-*-netbsd*
2577 OpenBSD/amd64 x86_64-*-openbsd*
2578 OpenBSD/alpha alpha*-*-openbsd*
2579 OpenBSD/sparc sparc-*-openbsd*
2580 OpenBSD/sparc64 sparc64-*-openbsd*
2582 * New debugging protocols
2584 M32R with SDI protocol m32r-*-elf*
2586 * "set prompt-escape-char" command deleted.
2588 The command "set prompt-escape-char" has been deleted. This command,
2589 and its very obscure effet on GDB's prompt, was never documented,
2590 tested, nor mentioned in the NEWS file.
2592 * OBSOLETE configurations and files
2594 Configurations that have been declared obsolete in this release have
2595 been commented out. Unless there is activity to revive these
2596 configurations, the next release of GDB will have their sources
2597 permanently REMOVED.
2599 Sun 3, running SunOS 3 m68*-*-sunos3*
2600 Sun 3, running SunOS 4 m68*-*-sunos4*
2601 Sun 2, running SunOS 3 m68000-*-sunos3*
2602 Sun 2, running SunOS 4 m68000-*-sunos4*
2603 Motorola 680x0 running LynxOS m68*-*-lynxos*
2604 AT&T 3b1/Unix pc m68*-att-*
2605 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2606 decstation mips-dec-* mips-little-*
2607 riscos mips-*-riscos* mips-*-sysv*
2608 sonymips mips-sony-*
2609 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2611 * REMOVED configurations and files
2613 SGI Irix-4.x mips-sgi-irix4 or iris4
2614 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2615 Z8000 simulator z8k-zilog-none or z8ksim
2616 Matsushita MN10200 w/simulator mn10200-*-*
2617 H8/500 simulator h8500-hitachi-hms or h8500hms
2618 HP/PA running BSD hppa*-*-bsd*
2619 HP/PA running OSF/1 hppa*-*-osf*
2620 HP/PA Pro target hppa*-*-pro*
2621 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2622 386BSD i[3456]86-*-bsd*
2623 Sequent family i[3456]86-sequent-sysv4*
2624 i[3456]86-sequent-sysv*
2625 i[3456]86-sequent-bsd*
2626 SPARC running LynxOS sparc-*-lynxos*
2627 SPARC running SunOS 4 sparc-*-sunos4*
2628 Tsqware Sparclet sparclet-*-*
2629 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2631 *** Changes in GDB 6.0:
2635 Support for debugging the Objective-C programming language has been
2636 integrated into GDB.
2638 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2640 DWARF 2's Call Frame Information makes available compiler generated
2641 information that more exactly describes the program's run-time stack.
2642 By using this information, GDB is able to provide more robust stack
2645 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2646 have been updated to use a new backtrace mechanism which includes
2647 DWARF 2 CFI support.
2651 GDB's remote protocol has been extended to include support for hosted
2652 file I/O (where the remote target uses GDB's file system). See GDB's
2653 remote protocol documentation for details.
2655 * All targets using the new architecture framework.
2657 All of GDB's targets have been updated to use the new internal
2658 architecture framework. The way is now open for future GDB releases
2659 to include cross-architecture native debugging support (i386 on amd64,
2662 * GNU/Linux's Thread Local Storage (TLS)
2664 GDB now includes support for for the GNU/Linux implementation of
2665 per-thread variables.
2667 * GNU/Linux's Native POSIX Thread Library (NPTL)
2669 GDB's thread code has been updated to work with either the new
2670 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2672 * Separate debug info.
2674 GDB, in conjunction with BINUTILS, now supports a mechanism for
2675 automatically loading debug information from a separate file. Instead
2676 of shipping full debug and non-debug versions of system libraries,
2677 system integrators can now instead ship just the stripped libraries
2678 and optional debug files.
2680 * DWARF 2 Location Expressions
2682 DWARF 2 Location Expressions allow the compiler to more completely
2683 describe the location of variables (even in optimized code) to the
2686 GDB now includes preliminary support for location expressions (support
2687 for DW_OP_piece is still missing).
2691 A number of long standing bugs that caused GDB to die while starting a
2692 Java application have been fixed. GDB's Java support is now
2693 considered "useable".
2695 * GNU/Linux support for fork, vfork, and exec.
2697 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2698 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2701 * GDB supports logging output to a file
2703 There are two new commands, "set logging" and "show logging", which can be
2704 used to capture GDB's output to a file.
2706 * The meaning of "detach" has changed for gdbserver
2708 The "detach" command will now resume the application, as documented. To
2709 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2712 * d10v, m68hc11 `regs' command deprecated
2714 The `info registers' command has been updated so that it displays the
2715 registers using a format identical to the old `regs' command.
2719 A new command, "maint set profile on/off", has been added. This command can
2720 be used to enable or disable profiling while running GDB, to profile a
2721 session or a set of commands. In addition there is a new configure switch,
2722 "--enable-profiling", which will cause GDB to be compiled with profiling
2723 data, for more informative profiling results.
2725 * Default MI syntax changed to "mi2".
2727 The default MI (machine interface) syntax, enabled by the command line
2728 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2729 "mi1", can be enabled by specifying the option "-i=mi1".
2731 Support for the original "mi0" syntax (included in GDB 5.0) has been
2734 Fix for gdb/192: removed extraneous space when displaying frame level.
2735 Fix for gdb/672: update changelist is now output in mi list format.
2736 Fix for gdb/702: a -var-assign that updates the value now shows up
2737 in a subsequent -var-update.
2739 * New native configurations.
2741 FreeBSD/amd64 x86_64-*-freebsd*
2743 * Multi-arched targets.
2745 HP/PA HPUX11 hppa*-*-hpux*
2746 Renesas M32R/D w/simulator m32r-*-elf*
2748 * OBSOLETE configurations and files
2750 Configurations that have been declared obsolete in this release have
2751 been commented out. Unless there is activity to revive these
2752 configurations, the next release of GDB will have their sources
2753 permanently REMOVED.
2755 Z8000 simulator z8k-zilog-none or z8ksim
2756 Matsushita MN10200 w/simulator mn10200-*-*
2757 H8/500 simulator h8500-hitachi-hms or h8500hms
2758 HP/PA running BSD hppa*-*-bsd*
2759 HP/PA running OSF/1 hppa*-*-osf*
2760 HP/PA Pro target hppa*-*-pro*
2761 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2762 Sequent family i[3456]86-sequent-sysv4*
2763 i[3456]86-sequent-sysv*
2764 i[3456]86-sequent-bsd*
2765 Tsqware Sparclet sparclet-*-*
2766 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2768 * REMOVED configurations and files
2771 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2772 IBM AIX PS/2 i[3456]86-*-aix
2773 i386 running Mach 3.0 i[3456]86-*-mach3*
2774 i386 running Mach i[3456]86-*-mach*
2775 i386 running OSF/1 i[3456]86-*osf1mk*
2776 HP/Apollo 68k Family m68*-apollo*-sysv*,
2778 m68*-hp-bsd*, m68*-hp-hpux*
2779 Argonaut Risc Chip (ARC) arc-*-*
2780 Mitsubishi D30V d30v-*-*
2781 Fujitsu FR30 fr30-*-elf*
2782 OS/9000 i[34]86-*-os9k
2783 I960 with MON960 i960-*-coff
2785 * MIPS $fp behavior changed
2787 The convenience variable $fp, for the MIPS, now consistently returns
2788 the address of the current frame's base. Previously, depending on the
2789 context, $fp could refer to either $sp or the current frame's base
2790 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2791 The GNU Source-Level Debugger''.
2793 *** Changes in GDB 5.3:
2795 * GNU/Linux shared library multi-threaded performance improved.
2797 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2798 `/proc', in preference to `ptrace' for memory reads. This may result
2799 in an improvement in the start-up time of multi-threaded, shared
2800 library applications when run under GDB. One GDB user writes: ``loads
2801 shared libs like mad''.
2803 * ``gdbserver'' now supports multi-threaded applications on some targets
2805 Support for debugging multi-threaded applications which use
2806 the GNU/Linux LinuxThreads package has been added for
2807 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2808 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2810 * GDB now supports C/C++ preprocessor macros.
2812 GDB now expands preprocessor macro invocations in C/C++ expressions,
2813 and provides various commands for showing macro definitions and how
2816 The new command `macro expand EXPRESSION' expands any macro
2817 invocations in expression, and shows the result.
2819 The new command `show macro MACRO-NAME' shows the definition of the
2820 macro named MACRO-NAME, and where it was defined.
2822 Most compilers don't include information about macros in the debugging
2823 information by default. In GCC 3.1, for example, you need to compile
2824 your program with the options `-gdwarf-2 -g3'. If the macro
2825 information is present in the executable, GDB will read it.
2827 * Multi-arched targets.
2829 DEC Alpha (partial) alpha*-*-*
2830 DEC VAX (partial) vax-*-*
2832 National Semiconductor NS32000 (partial) ns32k-*-*
2833 Motorola 68000 (partial) m68k-*-*
2834 Motorola MCORE mcore-*-*
2838 Fujitsu FRV architecture added by Red Hat frv*-*-*
2841 * New native configurations
2843 Alpha NetBSD alpha*-*-netbsd*
2844 SH NetBSD sh*-*-netbsdelf*
2845 MIPS NetBSD mips*-*-netbsd*
2846 UltraSPARC NetBSD sparc64-*-netbsd*
2848 * OBSOLETE configurations and files
2850 Configurations that have been declared obsolete in this release have
2851 been commented out. Unless there is activity to revive these
2852 configurations, the next release of GDB will have their sources
2853 permanently REMOVED.
2855 Mitsubishi D30V d30v-*-*
2856 OS/9000 i[34]86-*-os9k
2857 IBM AIX PS/2 i[3456]86-*-aix
2858 Fujitsu FR30 fr30-*-elf*
2859 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2860 Argonaut Risc Chip (ARC) arc-*-*
2861 i386 running Mach 3.0 i[3456]86-*-mach3*
2862 i386 running Mach i[3456]86-*-mach*
2863 i386 running OSF/1 i[3456]86-*osf1mk*
2864 HP/Apollo 68k Family m68*-apollo*-sysv*,
2866 m68*-hp-bsd*, m68*-hp-hpux*
2867 I960 with MON960 i960-*-coff
2869 * OBSOLETE languages
2871 CHILL, a Pascal like language used by telecommunications companies.
2873 * REMOVED configurations and files
2875 AMD 29k family via UDI a29k-amd-udi, udi29k
2876 A29K VxWorks a29k-*-vxworks
2877 AMD 29000 embedded, using EBMON a29k-none-none
2878 AMD 29000 embedded with COFF a29k-none-coff
2879 AMD 29000 embedded with a.out a29k-none-aout
2881 testsuite/gdb.hp/gdb.threads-hp/ directory
2883 * New command "set max-user-call-depth <nnn>"
2885 This command allows the user to limit the call depth of user-defined
2886 commands. The default is 1024.
2888 * Changes in FreeBSD/i386 native debugging.
2890 Support for the "generate-core-file" has been added.
2892 * New commands "dump", "append", and "restore".
2894 These commands allow data to be copied from target memory
2895 to a bfd-format or binary file (dump and append), and back
2896 from a file into memory (restore).
2898 * Improved "next/step" support on multi-processor Alpha Tru64.
2900 The previous single-step mechanism could cause unpredictable problems,
2901 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2902 of a software single-step mechanism prevents this.
2904 *** Changes in GDB 5.2.1:
2912 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2913 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2914 Fix, by Joel Brobecker imported from mainline.
2916 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2917 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2918 Fix, by Fred Fish, imported from mainline.
2920 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2921 Surprisingly enough, it works now.
2922 By Michal Ludvig, imported from mainline.
2924 i386 hardware watchpoint support:
2925 avoid misses on second run for some targets.
2926 By Pierre Muller, imported from mainline.
2928 *** Changes in GDB 5.2:
2930 * New command "set trust-readonly-sections on[off]".
2932 This command is a hint that tells gdb that read-only sections
2933 really are read-only (ie. that their contents will not change).
2934 In this mode, gdb will go to the object file rather than the
2935 target to read memory from read-only sections (such as ".text").
2936 This can be a significant performance improvement on some
2937 (notably embedded) targets.
2939 * New command "generate-core-file" (or "gcore").
2941 This new gdb command allows the user to drop a core file of the child
2942 process state at any time. So far it's been implemented only for
2943 GNU/Linux and Solaris, but should be relatively easily ported to other
2944 hosts. Argument is core file name (defaults to core.<pid>).
2946 * New command line option
2948 GDB now accepts --pid or -p followed by a process id.
2950 * Change in command line behavior -- corefiles vs. process ids.
2952 There is a subtle behavior in the way in which GDB handles
2953 command line arguments. The first non-flag argument is always
2954 a program to debug, but the second non-flag argument may either
2955 be a corefile or a process id. Previously, GDB would attempt to
2956 open the second argument as a corefile, and if that failed, would
2957 issue a superfluous error message and then attempt to attach it as
2958 a process. Now, if the second argument begins with a non-digit,
2959 it will be treated as a corefile. If it begins with a digit,
2960 GDB will attempt to attach it as a process, and if no such process
2961 is found, will then attempt to open it as a corefile.
2963 * Changes in ARM configurations.
2965 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2966 configuration is fully multi-arch.
2968 * New native configurations
2970 ARM NetBSD arm*-*-netbsd*
2971 x86 OpenBSD i[3456]86-*-openbsd*
2972 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2973 Sparc64 running FreeBSD sparc64-*-freebsd*
2977 Sanyo XStormy16 xstormy16-elf
2979 * OBSOLETE configurations and files
2981 Configurations that have been declared obsolete in this release have
2982 been commented out. Unless there is activity to revive these
2983 configurations, the next release of GDB will have their sources
2984 permanently REMOVED.
2986 AMD 29k family via UDI a29k-amd-udi, udi29k
2987 A29K VxWorks a29k-*-vxworks
2988 AMD 29000 embedded, using EBMON a29k-none-none
2989 AMD 29000 embedded with COFF a29k-none-coff
2990 AMD 29000 embedded with a.out a29k-none-aout
2992 testsuite/gdb.hp/gdb.threads-hp/ directory
2994 * REMOVED configurations and files
2996 TI TMS320C80 tic80-*-*
2998 PowerPC Solaris powerpcle-*-solaris*
2999 PowerPC Windows NT powerpcle-*-cygwin32
3000 PowerPC Netware powerpc-*-netware*
3001 Harris/CXUX m88k m88*-harris-cxux*
3002 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3003 ns32k-utek-sysv* ns32k-utek-*
3004 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3005 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3006 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3007 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3008 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3010 * Changes to command line processing
3012 The new `--args' feature can be used to specify command-line arguments
3013 for the inferior from gdb's command line.
3015 * Changes to key bindings
3017 There is a new `operate-and-get-next' function bound to `C-o'.
3019 *** Changes in GDB 5.1.1
3021 Fix compile problem on DJGPP.
3023 Fix a problem with floating-point registers on the i386 being
3026 Fix to stop GDB crashing on .debug_str debug info.
3028 Numerous documentation fixes.
3030 Numerous testsuite fixes.
3032 *** Changes in GDB 5.1:
3034 * New native configurations
3036 Alpha FreeBSD alpha*-*-freebsd*
3037 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3038 MIPS GNU/Linux mips*-*-linux*
3039 MIPS SGI Irix 6.x mips*-sgi-irix6*
3040 ia64 AIX ia64-*-aix*
3041 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3045 Motorola 68HC11 and 68HC12 m68hc11-elf
3047 UltraSparc running GNU/Linux sparc64-*-linux*
3049 * OBSOLETE configurations and files
3051 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3052 Harris/CXUX m88k m88*-harris-cxux*
3053 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3054 ns32k-utek-sysv* ns32k-utek-*
3055 TI TMS320C80 tic80-*-*
3057 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3058 PowerPC Solaris powerpcle-*-solaris*
3059 PowerPC Windows NT powerpcle-*-cygwin32
3060 PowerPC Netware powerpc-*-netware*
3061 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3062 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3063 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3064 Apple Macintosh (MPW) host N/A
3066 stuff.c (Program to stuff files into a specially prepared space in kdb)
3067 kdb-start.c (Main loop for the standalone kernel debugger)
3069 Configurations that have been declared obsolete in this release have
3070 been commented out. Unless there is activity to revive these
3071 configurations, the next release of GDB will have their sources
3072 permanently REMOVED.
3074 * REMOVED configurations and files
3076 Altos 3068 m68*-altos-*
3077 Convex c1-*-*, c2-*-*
3079 ARM RISCix arm-*-* (as host)
3083 * GDB has been converted to ISO C.
3085 GDB's source code has been converted to ISO C. In particular, the
3086 sources are fully protoized, and rely on standard headers being
3091 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3093 * The MI enabled by default.
3095 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3096 revised and enabled by default. Packages which use GDB as a debugging
3097 engine behind a UI or another front end are encouraged to switch to
3098 using the GDB/MI interface, instead of the old annotations interface
3099 which is now deprecated.
3101 * Support for debugging Pascal programs.
3103 GDB now includes support for debugging Pascal programs. The following
3104 main features are supported:
3106 - Pascal-specific data types such as sets;
3108 - automatic recognition of Pascal sources based on file-name
3111 - Pascal-style display of data types, variables, and functions;
3113 - a Pascal expression parser.
3115 However, some important features are not yet supported.
3117 - Pascal string operations are not supported at all;
3119 - there are some problems with boolean types;
3121 - Pascal type hexadecimal constants are not supported
3122 because they conflict with the internal variables format;
3124 - support for Pascal objects and classes is not full yet;
3126 - unlike Pascal, GDB is case-sensitive for symbol names.
3128 * Changes in completion.
3130 Commands such as `shell', `run' and `set args', which pass arguments
3131 to inferior programs, now complete on file names, similar to what
3132 users expect at the shell prompt.
3134 Commands which accept locations, such as `disassemble', `print',
3135 `breakpoint', `until', etc. now complete on filenames as well as
3136 program symbols. Thus, if you type "break foob TAB", and the source
3137 files linked into the programs include `foobar.c', that file name will
3138 be one of the candidates for completion. However, file names are not
3139 considered for completion after you typed a colon that delimits a file
3140 name from a name of a function in that file, as in "break foo.c:bar".
3142 `set demangle-style' completes on available demangling styles.
3144 * New platform-independent commands:
3146 It is now possible to define a post-hook for a command as well as a
3147 hook that runs before the command. For more details, see the
3148 documentation of `hookpost' in the GDB manual.
3150 * Changes in GNU/Linux native debugging.
3152 Support for debugging multi-threaded programs has been completely
3153 revised for all platforms except m68k and sparc. You can now debug as
3154 many threads as your system allows you to have.
3156 Attach/detach is supported for multi-threaded programs.
3158 Support for SSE registers was added for x86. This doesn't work for
3159 multi-threaded programs though.
3161 * Changes in MIPS configurations.
3163 Multi-arch support is enabled for all MIPS configurations.
3165 GDB can now be built as native debugger on SGI Irix 6.x systems for
3166 debugging n32 executables. (Debugging 64-bit executables is not yet
3169 * Unified support for hardware watchpoints in all x86 configurations.
3171 Most (if not all) native x86 configurations support hardware-assisted
3172 breakpoints and watchpoints in a unified manner. This support
3173 implements debug register sharing between watchpoints, which allows to
3174 put a virtually infinite number of watchpoints on the same address,
3175 and also supports watching regions up to 16 bytes with several debug
3178 The new maintenance command `maintenance show-debug-regs' toggles
3179 debugging print-outs in functions that insert, remove, and test
3180 watchpoints and hardware breakpoints.
3182 * Changes in the DJGPP native configuration.
3184 New command ``info dos sysinfo'' displays assorted information about
3185 the CPU, OS, memory, and DPMI server.
3187 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3188 display information about segment descriptors stored in GDT, LDT, and
3191 New commands ``info dos pde'' and ``info dos pte'' display entries
3192 from Page Directory and Page Tables (for now works with CWSDPMI only).
3193 New command ``info dos address-pte'' displays the Page Table entry for
3194 a given linear address.
3196 GDB can now pass command lines longer than 126 characters to the
3197 program being debugged (requires an update to the libdbg.a library
3198 which is part of the DJGPP development kit).
3200 DWARF2 debug info is now supported.
3202 It is now possible to `step' and `next' through calls to `longjmp'.
3204 * Changes in documentation.
3206 All GDB documentation was converted to GFDL, the GNU Free
3207 Documentation License.
3209 Tracepoints-related commands are now fully documented in the GDB
3212 TUI, the Text-mode User Interface, is now documented in the manual.
3214 Tracepoints-related commands are now fully documented in the GDB
3217 The "GDB Internals" manual now has an index. It also includes
3218 documentation of `ui_out' functions, GDB coding standards, x86
3219 hardware watchpoints, and memory region attributes.
3221 * GDB's version number moved to ``version.in''
3223 The Makefile variable VERSION has been replaced by the file
3224 ``version.in''. People creating GDB distributions should update the
3225 contents of this file.
3229 GUD support is now a standard part of the EMACS distribution.
3231 *** Changes in GDB 5.0:
3233 * Improved support for debugging FP programs on x86 targets
3235 Unified and much-improved support for debugging floating-point
3236 programs on all x86 targets. In particular, ``info float'' now
3237 displays the FP registers in the same format on all x86 targets, with
3238 greater level of detail.
3240 * Improvements and bugfixes in hardware-assisted watchpoints
3242 It is now possible to watch array elements, struct members, and
3243 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3244 on x86 targets no longer erroneously trigger when the address is
3247 * Improvements in the native DJGPP version of GDB
3249 The distribution now includes all the scripts and auxiliary files
3250 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3251 machines ``out of the box''.
3253 The DJGPP version can now debug programs that use signals. It is
3254 possible to catch signals that happened in the debuggee, deliver
3255 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3256 would kill the program being debugged.) Programs that hook hardware
3257 interrupts (keyboard, timer, etc.) can also be debugged.
3259 It is now possible to debug DJGPP programs that redirect their
3260 standard handles or switch them to raw (as opposed to cooked) mode, or
3261 even close them. The command ``run < foo > bar'' works as expected,
3262 and ``info terminal'' reports useful information about the debuggee's
3263 terminal, including raw/cooked mode, redirection, etc.
3265 The DJGPP version now uses termios functions for console I/O, which
3266 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3269 DOS-style file names with drive letters are now fully supported by
3272 It is now possible to debug DJGPP programs that switch their working
3273 directory. It is also possible to rerun the debuggee any number of
3274 times without restarting GDB; thus, you can use the same setup,
3275 breakpoints, etc. for many debugging sessions.
3277 * New native configurations
3279 ARM GNU/Linux arm*-*-linux*
3280 PowerPC GNU/Linux powerpc-*-linux*
3284 Motorola MCore mcore-*-*
3285 x86 VxWorks i[3456]86-*-vxworks*
3286 PowerPC VxWorks powerpc-*-vxworks*
3287 TI TMS320C80 tic80-*-*
3289 * OBSOLETE configurations
3291 Altos 3068 m68*-altos-*
3292 Convex c1-*-*, c2-*-*
3294 ARM RISCix arm-*-* (as host)
3297 Configurations that have been declared obsolete will be commented out,
3298 but the code will be left in place. If there is no activity to revive
3299 these configurations before the next release of GDB, the sources will
3300 be permanently REMOVED.
3302 * Gould support removed
3304 Support for the Gould PowerNode and NP1 has been removed.
3306 * New features for SVR4
3308 On SVR4 native platforms (such as Solaris), if you attach to a process
3309 without first loading a symbol file, GDB will now attempt to locate and
3310 load symbols from the running process's executable file.
3312 * Many C++ enhancements
3314 C++ support has been greatly improved. Overload resolution now works properly
3315 in almost all cases. RTTI support is on the way.
3317 * Remote targets can connect to a sub-program
3319 A popen(3) style serial-device has been added. This device starts a
3320 sub-process (such as a stand-alone simulator) and then communicates
3321 with that. The sub-program to run is specified using the syntax
3322 ``|<program> <args>'' vis:
3324 (gdb) set remotedebug 1
3325 (gdb) target extended-remote |mn10300-elf-sim program-args
3327 * MIPS 64 remote protocol
3329 A long standing bug in the mips64 remote protocol where by GDB
3330 expected certain 32 bit registers (ex SR) to be transfered as 32
3331 instead of 64 bits has been fixed.
3333 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3334 added to provide backward compatibility with older versions of GDB.
3336 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3338 The command ``set remotebinarydownload'' command has been replaced by
3339 ``set remote X-packet''. Other commands in ``set remote'' family
3340 include ``set remote P-packet''.
3342 * Breakpoint commands accept ranges.
3344 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3345 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3346 ``tracepoint passcount'' also accepts a range of tracepoints.
3348 * ``apropos'' command added.
3350 The ``apropos'' command searches through command names and
3351 documentation strings, printing out matches, making it much easier to
3352 try to find a command that does what you are looking for.
3356 A new machine oriented interface (MI) has been added to GDB. This
3357 interface is designed for debug environments running GDB as a separate
3358 process. This is part of the long term libGDB project. See the
3359 "GDB/MI" chapter of the GDB manual for further information. It can be
3360 enabled by configuring with:
3362 .../configure --enable-gdbmi
3364 *** Changes in GDB-4.18:
3366 * New native configurations
3368 HP-UX 10.20 hppa*-*-hpux10.20
3369 HP-UX 11.x hppa*-*-hpux11.0*
3370 M68K GNU/Linux m68*-*-linux*
3374 Fujitsu FR30 fr30-*-elf*
3375 Intel StrongARM strongarm-*-*
3376 Mitsubishi D30V d30v-*-*
3378 * OBSOLETE configurations
3380 Gould PowerNode, NP1 np1-*-*, pn-*-*
3382 Configurations that have been declared obsolete will be commented out,
3383 but the code will be left in place. If there is no activity to revive
3384 these configurations before the next release of GDB, the sources will
3385 be permanently REMOVED.
3389 As a compatibility experiment, GDB's source files buildsym.h and
3390 buildsym.c have been converted to pure standard C, no longer
3391 containing any K&R compatibility code. We believe that all systems in
3392 use today either come with a standard C compiler, or have a GCC port
3393 available. If this is not true, please report the affected
3394 configuration to bug-gdb@gnu.org immediately. See the README file for
3395 information about getting a standard C compiler if you don't have one
3400 GDB now uses readline 2.2.
3402 * set extension-language
3404 You can now control the mapping between filename extensions and source
3405 languages by using the `set extension-language' command. For instance,
3406 you can ask GDB to treat .c files as C++ by saying
3407 set extension-language .c c++
3408 The command `info extensions' lists all of the recognized extensions
3409 and their associated languages.
3411 * Setting processor type for PowerPC and RS/6000
3413 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3414 you can use the `set processor' command to specify what variant of the
3415 PowerPC family you are debugging. The command
3419 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3420 following PowerPC and RS6000 variants:
3422 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3423 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3425 403GC IBM PowerPC 403GC
3426 505 Motorola PowerPC 505
3427 860 Motorola PowerPC 860 or 850
3428 601 Motorola PowerPC 601
3429 602 Motorola PowerPC 602
3430 603 Motorola/IBM PowerPC 603 or 603e
3431 604 Motorola PowerPC 604 or 604e
3432 750 Motorola/IBM PowerPC 750 or 750
3434 At the moment, this command just tells GDB what to name the
3435 special-purpose processor registers. Since almost all the affected
3436 registers are inaccessible to user-level programs, this command is
3437 only useful for remote debugging in its present form.
3441 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3442 more extensive support for HP-UX. Added features include shared
3443 library support, kernel threads and hardware watchpoints for 11.00,
3444 support for HP's ANSI C and C++ compilers, and a compatibility mode
3445 for xdb and dbx commands.
3449 HP's donation includes the new concept of catchpoints, which is a
3450 generalization of the old catch command. On HP-UX, it is now possible
3451 to catch exec, fork, and vfork, as well as library loading.
3453 This means that the existing catch command has changed; its first
3454 argument now specifies the type of catch to be set up. See the
3455 output of "help catch" for a list of catchpoint types.
3457 * Debugging across forks
3459 On HP-UX, you can choose which process to debug when a fork() happens
3464 HP has donated a curses-based terminal user interface (TUI). To get
3465 it, build with --enable-tui. Although this can be enabled for any
3466 configuration, at present it only works for native HP debugging.
3468 * GDB remote protocol additions
3470 A new protocol packet 'X' that writes binary data is now available.
3471 Default behavior is to try 'X', then drop back to 'M' if the stub
3472 fails to respond. The settable variable `remotebinarydownload'
3473 allows explicit control over the use of 'X'.
3475 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3476 full 64-bit address. The command
3478 set remoteaddresssize 32
3480 can be used to revert to the old behaviour. For existing remote stubs
3481 the change should not be noticed, as the additional address information
3484 In order to assist in debugging stubs, you may use the maintenance
3485 command `packet' to send any text string to the stub. For instance,
3487 maint packet heythere
3489 sends the packet "$heythere#<checksum>". Note that it is very easy to
3490 disrupt a debugging session by sending the wrong packet at the wrong
3493 The compare-sections command allows you to compare section data on the
3494 target to what is in the executable file without uploading or
3495 downloading, by comparing CRC checksums.
3497 * Tracing can collect general expressions
3499 You may now collect general expressions at tracepoints. This requires
3500 further additions to the target-side stub; see tracepoint.c and
3501 doc/agentexpr.texi for further details.
3503 * mask-address variable for Mips
3505 For Mips targets, you may control the zeroing of the upper 32 bits of
3506 a 64-bit address by entering `set mask-address on'. This is mainly
3507 of interest to users of embedded R4xxx and R5xxx processors.
3509 * Higher serial baud rates
3511 GDB's serial code now allows you to specify baud rates 57600, 115200,
3512 230400, and 460800 baud. (Note that your host system may not be able
3513 to achieve all of these rates.)
3517 The i960 configuration now includes an initial implementation of a
3518 builtin simulator, contributed by Jim Wilson.
3521 *** Changes in GDB-4.17:
3523 * New native configurations
3525 Alpha GNU/Linux alpha*-*-linux*
3526 Unixware 2.x i[3456]86-unixware2*
3527 Irix 6.x mips*-sgi-irix6*
3528 PowerPC GNU/Linux powerpc-*-linux*
3529 PowerPC Solaris powerpcle-*-solaris*
3530 Sparc GNU/Linux sparc-*-linux*
3531 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3535 Argonaut Risc Chip (ARC) arc-*-*
3536 Hitachi H8/300S h8300*-*-*
3537 Matsushita MN10200 w/simulator mn10200-*-*
3538 Matsushita MN10300 w/simulator mn10300-*-*
3539 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3540 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3541 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3542 Mitsubishi D10V w/simulator d10v-*-*
3543 Mitsubishi M32R/D w/simulator m32r-*-elf*
3544 Tsqware Sparclet sparclet-*-*
3545 NEC V850 w/simulator v850-*-*
3547 * New debugging protocols
3549 ARM with RDI protocol arm*-*-*
3550 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3551 DDB and LSI variants of PMON protocol mips*-*-*
3552 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3553 PowerPC with SDS protocol powerpc{,le}-*-eabi
3554 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3558 All configurations can now understand and use the DWARF 2 debugging
3559 format. The choice is automatic, if the symbol file contains DWARF 2
3564 GDB now includes basic Java language support. This support is
3565 only useful with Java compilers that produce native machine code.
3567 * solib-absolute-prefix and solib-search-path
3569 For SunOS and SVR4 shared libraries, you may now set the prefix for
3570 loading absolute shared library symbol files, and the search path for
3571 locating non-absolute shared library symbol files.
3573 * Live range splitting
3575 GDB can now effectively debug code for which GCC has performed live
3576 range splitting as part of its optimization. See gdb/doc/LRS for
3577 more details on the expected format of the stabs information.
3581 GDB's support for the GNU Hurd, including thread debugging, has been
3582 updated to work with current versions of the Hurd.
3586 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3587 instruction set. ARM GDB automatically detects when Thumb
3588 instructions are in use, and adjusts disassembly and backtracing
3593 GDB's MIPS target configurations now handle the MIP16 16-bit
3598 GDB now includes support for overlays; if an executable has been
3599 linked such that multiple sections are based at the same address, GDB
3600 will decide which section to use for symbolic info. You can choose to
3601 control the decision manually, using overlay commands, or implement
3602 additional target-side support and use "overlay load-target" to bring
3603 in the overlay mapping. Do "help overlay" for more detail.
3607 The command "info symbol <address>" displays information about
3608 the symbol at the specified address.
3612 The standard remote protocol now includes an extension that allows
3613 asynchronous collection and display of trace data. This requires
3614 extensive support in the target-side debugging stub. Tracing mode
3615 includes a new interaction mode in GDB and new commands: see the
3616 file tracepoint.c for more details.
3620 Configurations for embedded MIPS now include a simulator contributed
3621 by Cygnus Solutions. The simulator supports the instruction sets
3622 of most MIPS variants.
3626 Sparc configurations may now include the ERC32 simulator contributed
3627 by the European Space Agency. The simulator is not built into
3628 Sparc targets by default; configure with --enable-sim to include it.
3632 For target configurations that may include multiple variants of a
3633 basic architecture (such as MIPS and SH), you may now set the
3634 architecture explicitly. "set arch" sets, "info arch" lists
3635 the possible architectures.
3637 *** Changes in GDB-4.16:
3639 * New native configurations
3641 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3642 M68K NetBSD m68k-*-netbsd*
3643 PowerPC AIX 4.x powerpc-*-aix*
3644 PowerPC MacOS powerpc-*-macos*
3645 PowerPC Windows NT powerpcle-*-cygwin32
3646 RS/6000 AIX 4.x rs6000-*-aix4*
3650 ARM with RDP protocol arm-*-*
3651 I960 with MON960 i960-*-coff
3652 MIPS VxWorks mips*-*-vxworks*
3653 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3654 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3656 Matra Sparclet sparclet-*-*
3660 The powerpc-eabi configuration now includes the PSIM simulator,
3661 contributed by Andrew Cagney, with assistance from Mike Meissner.
3662 PSIM is a very elaborate model of the PowerPC, including not only
3663 basic instruction set execution, but also details of execution unit
3664 performance and I/O hardware. See sim/ppc/README for more details.
3668 GDB now works with Solaris 2.5.
3670 * Windows 95/NT native
3672 GDB will now work as a native debugger on Windows 95 and Windows NT.
3673 To build it from source, you must use the "gnu-win32" environment,
3674 which uses a DLL to emulate enough of Unix to run the GNU tools.
3675 Further information, binaries, and sources are available at
3676 ftp.cygnus.com, under pub/gnu-win32.
3678 * dont-repeat command
3680 If a user-defined command includes the command `dont-repeat', then the
3681 command will not be repeated if the user just types return. This is
3682 useful if the command is time-consuming to run, so that accidental
3683 extra keystrokes don't run the same command many times.
3685 * Send break instead of ^C
3687 The standard remote protocol now includes an option to send a break
3688 rather than a ^C to the target in order to interrupt it. By default,
3689 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3691 * Remote protocol timeout
3693 The standard remote protocol includes a new variable `remotetimeout'
3694 that allows you to set the number of seconds before GDB gives up trying
3695 to read from the target. The default value is 2.
3697 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3699 By default GDB will automatically keep track of objects as they are
3700 loaded and unloaded by the dynamic linker. By using the command `set
3701 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3702 when shared library events occur, thus allowing you to set breakpoints
3703 in shared libraries which are explicitly loaded by the inferior.
3705 Note this feature does not work on hpux8. On hpux9 you must link
3706 /usr/lib/end.o into your program. This feature should work
3707 automatically on hpux10.
3709 * Irix 5.x hardware watchpoint support
3711 Irix 5 configurations now support the use of hardware watchpoints.
3713 * Mips protocol "SYN garbage limit"
3715 When debugging a Mips target using the `target mips' protocol, you
3716 may set the number of characters that GDB will ignore by setting
3717 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3718 every character. The default value is 1050.
3720 * Recording and replaying remote debug sessions
3722 If you set `remotelogfile' to the name of a file, gdb will write to it
3723 a recording of a remote debug session. This recording may then be
3724 replayed back to gdb using "gdbreplay". See gdbserver/README for
3725 details. This is useful when you have a problem with GDB while doing
3726 remote debugging; you can make a recording of the session and send it
3727 to someone else, who can then recreate the problem.
3729 * Speedups for remote debugging
3731 GDB includes speedups for downloading and stepping MIPS systems using
3732 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3733 and more efficient S-record downloading.
3735 * Memory use reductions and statistics collection
3737 GDB now uses less memory and reports statistics about memory usage.
3738 Try the `maint print statistics' command, for example.
3740 *** Changes in GDB-4.15:
3742 * Psymtabs for XCOFF
3744 The symbol reader for AIX GDB now uses partial symbol tables. This
3745 can greatly improve startup time, especially for large executables.
3747 * Remote targets use caching
3749 Remote targets now use a data cache to speed up communication with the
3750 remote side. The data cache could lead to incorrect results because
3751 it doesn't know about volatile variables, thus making it impossible to
3752 debug targets which use memory mapped I/O devices. `set remotecache
3753 off' turns the the data cache off.
3755 * Remote targets may have threads
3757 The standard remote protocol now includes support for multiple threads
3758 in the target system, using new protocol commands 'H' and 'T'. See
3759 gdb/remote.c for details.
3763 If GDB is configured with `--enable-netrom', then it will include
3764 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3765 acts as though it is a bank of ROM on the target board, but you can
3766 write into it over the network. GDB's support consists only of
3767 support for fast loading into the emulated ROM; to debug, you must use
3768 another protocol, such as standard remote protocol. The usual
3769 sequence is something like
3771 target nrom <netrom-hostname>
3773 target remote <netrom-hostname>:1235
3777 GDB now includes support for the Apple Macintosh, as a host only. It
3778 may be run as either an MPW tool or as a standalone application, and
3779 it can debug through the serial port. All the usual GDB commands are
3780 available, but to the target command, you must supply "serial" as the
3781 device type instead of "/dev/ttyXX". See mpw-README in the main
3782 directory for more information on how to build. The MPW configuration
3783 scripts */mpw-config.in support only a few targets, and only the
3784 mips-idt-ecoff target has been tested.
3788 GDB configuration now uses autoconf. This is not user-visible,
3789 but does simplify configuration and building.
3793 GDB now supports hpux10.
3795 *** Changes in GDB-4.14:
3797 * New native configurations
3799 x86 FreeBSD i[345]86-*-freebsd
3800 x86 NetBSD i[345]86-*-netbsd
3801 NS32k NetBSD ns32k-*-netbsd
3802 Sparc NetBSD sparc-*-netbsd
3806 A29K VxWorks a29k-*-vxworks
3807 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3808 CPU32 EST-300 emulator m68*-*-est*
3809 PowerPC ELF powerpc-*-elf
3812 * Alpha OSF/1 support for procfs
3814 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3815 possible to attach to running processes. As the mounting of the /proc
3816 filesystem is optional on the Alpha, GDB automatically determines
3817 the availability of /proc during startup. This can lead to problems
3818 if /proc is unmounted after GDB has been started.
3820 * Arguments to user-defined commands
3822 User commands may accept up to 10 arguments separated by whitespace.
3823 Arguments are accessed within the user command via $arg0..$arg9. A
3826 print $arg0 + $arg1 + $arg2
3828 To execute the command use:
3831 Defines the command "adder" which prints the sum of its three arguments.
3832 Note the arguments are text substitutions, so they may reference variables,
3833 use complex expressions, or even perform inferior function calls.
3835 * New `if' and `while' commands
3837 This makes it possible to write more sophisticated user-defined
3838 commands. Both commands take a single argument, which is the
3839 expression to evaluate, and must be followed by the commands to
3840 execute, one per line, if the expression is nonzero, the list being
3841 terminated by the word `end'. The `if' command list may include an
3842 `else' word, which causes the following commands to be executed only
3843 if the expression is zero.
3845 * Fortran source language mode
3847 GDB now includes partial support for Fortran 77. It will recognize
3848 Fortran programs and can evaluate a subset of Fortran expressions, but
3849 variables and functions may not be handled correctly. GDB will work
3850 with G77, but does not yet know much about symbols emitted by other
3853 * Better HPUX support
3855 Most debugging facilities now work on dynamic executables for HPPAs
3856 running hpux9 or later. You can attach to running dynamically linked
3857 processes, but by default the dynamic libraries will be read-only, so
3858 for instance you won't be able to put breakpoints in them. To change
3859 that behavior do the following before running the program:
3865 This will cause the libraries to be mapped private and read-write.
3866 To revert to the normal behavior, do this:
3872 You cannot set breakpoints or examine data in the library until after
3873 the library is loaded if the function/data symbols do not have
3876 GDB can now also read debug symbols produced by the HP C compiler on
3877 HPPAs (sorry, no C++, Fortran or 68k support).
3879 * Target byte order now dynamically selectable
3881 You can choose which byte order to use with a target system, via the
3882 commands "set endian big" and "set endian little", and you can see the
3883 current setting by using "show endian". You can also give the command
3884 "set endian auto", in which case GDB will use the byte order
3885 associated with the executable. Currently, only embedded MIPS
3886 configurations support dynamic selection of target byte order.
3888 * New DOS host serial code
3890 This version uses DPMI interrupts to handle buffered I/O, so you
3891 no longer need to run asynctsr when debugging boards connected to
3894 *** Changes in GDB-4.13:
3896 * New "complete" command
3898 This lists all the possible completions for the rest of the line, if it
3899 were to be given as a command itself. This is intended for use by emacs.
3901 * Trailing space optional in prompt
3903 "set prompt" no longer adds a space for you after the prompt you set. This
3904 allows you to set a prompt which ends in a space or one that does not.
3906 * Breakpoint hit counts
3908 "info break" now displays a count of the number of times the breakpoint
3909 has been hit. This is especially useful in conjunction with "ignore"; you
3910 can ignore a large number of breakpoint hits, look at the breakpoint info
3911 to see how many times the breakpoint was hit, then run again, ignoring one
3912 less than that number, and this will get you quickly to the last hit of
3915 * Ability to stop printing at NULL character
3917 "set print null-stop" will cause GDB to stop printing the characters of
3918 an array when the first NULL is encountered. This is useful when large
3919 arrays actually contain only short strings.
3921 * Shared library breakpoints
3923 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3924 breakpoints in shared libraries before the executable is run.
3926 * Hardware watchpoints
3928 There is a new hardware breakpoint for the watch command for sparclite
3929 targets. See gdb/sparclite/hw_breakpoint.note.
3931 Hardware watchpoints are also now supported under GNU/Linux.
3935 Annotations have been added. These are for use with graphical interfaces,
3936 and are still experimental. Currently only gdba.el uses these.
3938 * Improved Irix 5 support
3940 GDB now works properly with Irix 5.2.
3942 * Improved HPPA support
3944 GDB now works properly with the latest GCC and GAS.
3946 * New native configurations
3948 Sequent PTX4 i[34]86-sequent-ptx4
3949 HPPA running OSF/1 hppa*-*-osf*
3950 Atari TT running SVR4 m68*-*-sysv4*
3951 RS/6000 LynxOS rs6000-*-lynxos*
3955 OS/9000 i[34]86-*-os9k
3956 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3959 * Hitachi SH7000 and E7000-PC ICE support
3961 There is now support for communicating with the Hitachi E7000-PC ICE.
3962 This is available automatically when GDB is configured for the SH.
3966 As usual, a variety of small fixes and improvements, both generic
3967 and configuration-specific. See the ChangeLog for more detail.
3969 *** Changes in GDB-4.12:
3971 * Irix 5 is now supported
3975 GDB-4.12 on the HPPA has a number of changes which make it unable
3976 to debug the output from the currently released versions of GCC and
3977 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3978 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3979 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3982 *** Changes in GDB-4.11:
3984 * User visible changes:
3988 The "set remotedebug" option is now consistent between the mips remote
3989 target, remote targets using the gdb-specific protocol, UDI (AMD's
3990 debug protocol for the 29k) and the 88k bug monitor. It is now an
3991 integer specifying a debug level (normally 0 or 1, but 2 means more
3992 debugging info for the mips target).
3994 * DEC Alpha native support
3996 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3997 debug info, but GDB works fairly well with the DEC compiler and should
3998 work with a future GCC release. See the README file for a few
3999 Alpha-specific notes.
4001 * Preliminary thread implementation
4003 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4005 * LynxOS native and target support for 386
4007 This release has been hosted on LynxOS 2.2, and also can be configured
4008 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4011 * Improvements in C++ mangling/demangling.
4013 This release has much better g++ debugging, specifically in name
4014 mangling/demangling, virtual function calls, print virtual table,
4015 call methods, ...etc.
4017 *** Changes in GDB-4.10:
4019 * User visible changes:
4021 Remote debugging using the GDB-specific (`target remote') protocol now
4022 supports the `load' command. This is only useful if you have some
4023 other way of getting the stub to the target system, and you can put it
4024 somewhere in memory where it won't get clobbered by the download.
4026 Filename completion now works.
4028 When run under emacs mode, the "info line" command now causes the
4029 arrow to point to the line specified. Also, "info line" prints
4030 addresses in symbolic form (as well as hex).
4032 All vxworks based targets now support a user settable option, called
4033 vxworks-timeout. This option represents the number of seconds gdb
4034 should wait for responses to rpc's. You might want to use this if
4035 your vxworks target is, perhaps, a slow software simulator or happens
4036 to be on the far side of a thin network line.
4040 This release contains support for using a DEC alpha as a GDB host for
4041 cross debugging. Native alpha debugging is not supported yet.
4044 *** Changes in GDB-4.9:
4048 This is the first GDB release which is accompanied by a matching testsuite.
4049 The testsuite requires installation of dejagnu, which should be available
4050 via ftp from most sites that carry GNU software.
4054 'Cfront' style demangling has had its name changed to 'ARM' style, to
4055 emphasize that it was written from the specifications in the C++ Annotated
4056 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4057 disclaimers, it still generated too much confusion with users attempting to
4058 use gdb with AT&T cfront.
4062 GDB now uses a standard remote interface to a simulator library.
4063 So far, the library contains simulators for the Zilog Z8001/2, the
4064 Hitachi H8/300, H8/500 and Super-H.
4066 * New targets supported
4068 H8/300 simulator h8300-hitachi-hms or h8300hms
4069 H8/500 simulator h8500-hitachi-hms or h8500hms
4070 SH simulator sh-hitachi-hms or sh
4071 Z8000 simulator z8k-zilog-none or z8ksim
4072 IDT MIPS board over serial line mips-idt-ecoff
4074 Cross-debugging to GO32 targets is supported. It requires a custom
4075 version of the i386-stub.c module which is integrated with the
4076 GO32 memory extender.
4078 * New remote protocols
4080 MIPS remote debugging protocol.
4082 * New source languages supported
4084 This version includes preliminary support for Chill, a Pascal like language
4085 used by telecommunications companies. Chill support is also being integrated
4086 into the GNU compiler, but we don't know when it will be publically available.
4089 *** Changes in GDB-4.8:
4091 * HP Precision Architecture supported
4093 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4094 version of this support was available as a set of patches from the
4095 University of Utah. GDB does not support debugging of programs
4096 compiled with the HP compiler, because HP will not document their file
4097 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4098 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4100 Many problems in the preliminary version have been fixed.
4102 * Faster and better demangling
4104 We have improved template demangling and fixed numerous bugs in the GNU style
4105 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4106 character types (wchar_t) are now supported. Demangling of each symbol is now
4107 only done once, and is cached when the symbol table for a file is read in.
4108 This results in a small increase in memory usage for C programs, a moderate
4109 increase in memory usage for C++ programs, and a fantastic speedup in
4112 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4113 from the specifications in the Annotated Reference Manual, which AT&T's
4114 compiler does not actually implement.
4116 * G++ multiple inheritance compiler problem
4118 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4119 inheritance lattices was reworked to properly discover ambiguities. We
4120 recently found an example which causes this new algorithm to fail in a
4121 very subtle way, producing bad debug information for those classes.
4122 The file 'gcc.patch' (in this directory) can be applied to gcc to
4123 circumvent the problem. A future GCC release will contain a complete
4126 The previous G++ debug info problem (mentioned below for the gdb-4.7
4127 release) is fixed in gcc version 2.3.2.
4129 * Improved configure script
4131 The `configure' script will now attempt to guess your system type if
4132 you don't supply a host system type. The old scheme of supplying a
4133 host system triplet is preferable over using this. All the magic is
4134 done in the new `config.guess' script. Examine it for details.
4136 We have also brought our configure script much more in line with the FSF's
4137 version. It now supports the --with-xxx options. In particular,
4138 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4139 The resulting GDB will not be able to read arbitrary object file formats --
4140 only the format ``expected'' to be used on the configured target system.
4141 We hope to make this the default in a future release.
4143 * Documentation improvements
4145 There's new internal documentation on how to modify GDB, and how to
4146 produce clean changes to the code. We implore people to read it
4147 before submitting changes.
4149 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4150 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4151 `info' files are also provided. To build `info' files from scratch,
4152 you will need the latest `makeinfo' release, which will be available in
4153 a future texinfo-X.Y release.
4155 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4156 We're not sure exactly which versions have this problem, but it has
4157 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4158 or better. If that isn't possible, there is a patch in
4159 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4160 around this problem.
4164 GDB now supports array constants that can be used in expressions typed in by
4165 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4166 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4169 The new directory `gdb/sparclite' contains a program that demonstrates
4170 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4172 * New native hosts supported
4174 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4175 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4177 * New targets supported
4179 AMD 29k family via UDI a29k-amd-udi or udi29k
4181 * New file formats supported
4183 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4184 HPUX core files, and SCO 3.2v2 core files.
4188 Attaching to processes now works again; thanks for the many bug reports.
4190 We have also stomped on a bunch of core dumps caused by
4191 printf_filtered("%s") problems.
4193 We eliminated a copyright problem on the rpc and ptrace header files
4194 for VxWorks, which was discovered at the last minute during the 4.7
4195 release. You should now be able to build a VxWorks GDB.
4197 You can now interrupt gdb while an attached process is running. This
4198 will cause the attached process to stop, and give control back to GDB.
4200 We fixed problems caused by using too many file descriptors
4201 for reading symbols from object files and libraries. This was
4202 especially a problem for programs that used many (~100) shared
4205 The `step' command now only enters a subroutine if there is line number
4206 information for the subroutine. Otherwise it acts like the `next'
4207 command. Previously, `step' would enter subroutines if there was
4208 any debugging information about the routine. This avoids problems
4209 when using `cc -g1' on MIPS machines.
4211 * Internal improvements
4213 GDB's internal interfaces have been improved to make it easier to support
4214 debugging of multiple languages in the future.
4216 GDB now uses a common structure for symbol information internally.
4217 Minimal symbols (derived from linkage symbols in object files), partial
4218 symbols (from a quick scan of debug information), and full symbols
4219 contain a common subset of information, making it easier to write
4220 shared code that handles any of them.
4222 * New command line options
4224 We now accept --silent as an alias for --quiet.
4228 The memory-mapped-malloc library is now licensed under the GNU Library
4229 General Public License.
4231 *** Changes in GDB-4.7:
4233 * Host/native/target split
4235 GDB has had some major internal surgery to untangle the support for
4236 hosts and remote targets. Now, when you configure GDB for a remote
4237 target, it will no longer load in all of the support for debugging
4238 local programs on the host. When fully completed and tested, this will
4239 ensure that arbitrary host/target combinations are possible.
4241 The primary conceptual shift is to separate the non-portable code in
4242 GDB into three categories. Host specific code is required any time GDB
4243 is compiled on that host, regardless of the target. Target specific
4244 code relates to the peculiarities of the target, but can be compiled on
4245 any host. Native specific code is everything else: it can only be
4246 built when the host and target are the same system. Child process
4247 handling and core file support are two common `native' examples.
4249 GDB's use of /proc for controlling Unix child processes is now cleaner.
4250 It has been split out into a single module under the `target_ops' vector,
4251 plus two native-dependent functions for each system that uses /proc.
4253 * New hosts supported
4255 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4256 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4257 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4259 * New targets supported
4261 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4262 68030 and CPU32 m68030-*-*, m68332-*-*
4264 * New native hosts supported
4266 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4267 (386bsd is not well tested yet)
4268 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4270 * New file formats supported
4272 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4273 supports reading of `a.out.adobe' object files, which are an a.out
4274 format extended with minimal information about multiple sections.
4278 `show copying' is the same as the old `info copying'.
4279 `show warranty' is the same as `info warrantee'.
4280 These were renamed for consistency. The old commands continue to work.
4282 `info handle' is a new alias for `info signals'.
4284 You can now define pre-command hooks, which attach arbitrary command
4285 scripts to any command. The commands in the hook will be executed
4286 prior to the user's command. You can also create a hook which will be
4287 executed whenever the program stops. See gdb.texinfo.
4291 We now deal with Cfront style name mangling, and can even extract type
4292 info from mangled symbols. GDB can automatically figure out which
4293 symbol mangling style your C++ compiler uses.
4295 Calling of methods and virtual functions has been improved as well.
4299 The crash that occured when debugging Sun Ansi-C compiled binaries is
4300 fixed. This was due to mishandling of the extra N_SO stabs output
4303 We also finally got Ultrix 4.2 running in house, and fixed core file
4304 support, with help from a dozen people on the net.
4306 John M. Farrell discovered that the reason that single-stepping was so
4307 slow on all of the Mips based platforms (primarily SGI and DEC) was
4308 that we were trying to demangle and lookup a symbol used for internal
4309 purposes on every instruction that was being stepped through. Changing
4310 the name of that symbol so that it couldn't be mistaken for a C++
4311 mangled symbol sped things up a great deal.
4313 Rich Pixley sped up symbol lookups in general by getting much smarter
4314 about when C++ symbol mangling is necessary. This should make symbol
4315 completion (TAB on the command line) much faster. It's not as fast as
4316 we'd like, but it's significantly faster than gdb-4.6.
4320 A new user controllable variable 'call_scratch_address' can
4321 specify the location of a scratch area to be used when GDB
4322 calls a function in the target. This is necessary because the
4323 usual method of putting the scratch area on the stack does not work
4324 in systems that have separate instruction and data spaces.
4326 We integrated changes to support the 29k UDI (Universal Debugger
4327 Interface), but discovered at the last minute that we didn't have all
4328 of the appropriate copyright paperwork. We are working with AMD to
4329 resolve this, and hope to have it available soon.
4333 We have sped up the remote serial line protocol, especially for targets
4334 with lots of registers. It now supports a new `expedited status' ('T')
4335 message which can be used in place of the existing 'S' status message.
4336 This allows the remote stub to send only the registers that GDB
4337 needs to make a quick decision about single-stepping or conditional
4338 breakpoints, eliminating the need to fetch the entire register set for
4339 each instruction being stepped through.
4341 The GDB remote serial protocol now implements a write-through cache for
4342 registers, only re-reading the registers if the target has run.
4344 There is also a new remote serial stub for SPARC processors. You can
4345 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4346 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4347 processor with a serial port.
4351 Configure.in files have become much easier to read and modify. A new
4352 `table driven' format makes it more obvious what configurations are
4353 supported, and what files each one uses.
4357 There is a new opcodes library which will eventually contain all of the
4358 disassembly routines and opcode tables. At present, it only contains
4359 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4360 disassembler (binutils/objdump) to share these routines.
4362 The libiberty library is now copylefted under the GNU Library General
4363 Public License. This allows more liberal use, and was done so libg++
4364 can use it. This makes no difference to GDB, since the Library License
4365 grants all the rights from the General Public License.
4369 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4370 reference to the stabs symbol info used by the debugger. It is (as far
4371 as we know) the only published document on this fascinating topic. We
4372 encourage you to read it, compare it to the stabs information on your
4373 system, and send improvements on the document in general (to
4374 bug-gdb@prep.ai.mit.edu).
4376 And, of course, many bugs have been fixed.
4379 *** Changes in GDB-4.6:
4381 * Better support for C++ function names
4383 GDB now accepts as input the "demangled form" of C++ overloaded function
4384 names and member function names, and can do command completion on such names
4385 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4386 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4387 Make use of command completion, it is your friend.
4389 GDB also now accepts a variety of C++ mangled symbol formats. They are
4390 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4391 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4392 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4393 for the list of formats.
4395 * G++ symbol mangling problem
4397 Recent versions of gcc have a bug in how they emit debugging information for
4398 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4399 directory) can be applied to gcc to fix the problem. Alternatively, if you
4400 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4401 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4402 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4405 * New 'maintenance' command
4407 All of the commands related to hacking GDB internals have been moved out of
4408 the main command set, and now live behind the 'maintenance' command. This
4409 can also be abbreviated as 'mt'. The following changes were made:
4411 dump-me -> maintenance dump-me
4412 info all-breakpoints -> maintenance info breakpoints
4413 printmsyms -> maintenance print msyms
4414 printobjfiles -> maintenance print objfiles
4415 printpsyms -> maintenance print psymbols
4416 printsyms -> maintenance print symbols
4418 The following commands are new:
4420 maintenance demangle Call internal GDB demangler routine to
4421 demangle a C++ link name and prints the result.
4422 maintenance print type Print a type chain for a given symbol
4424 * Change to .gdbinit file processing
4426 We now read the $HOME/.gdbinit file before processing the argv arguments
4427 (e.g. reading symbol files or core files). This allows global parameters to
4428 be set, which will apply during the symbol reading. The ./.gdbinit is still
4429 read after argv processing.
4431 * New hosts supported
4433 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4435 GNU/Linux support i386-unknown-linux or linux
4437 We are also including code to support the HP/PA running BSD and HPUX. This
4438 is almost guaranteed not to work, as we didn't have time to test or build it
4439 for this release. We are including it so that the more adventurous (or
4440 masochistic) of you can play with it. We also had major problems with the
4441 fact that the compiler that we got from HP doesn't support the -g option.
4444 * New targets supported
4446 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4448 * More smarts about finding #include files
4450 GDB now remembers the compilation directory for all include files, and for
4451 all files from which C is generated (like yacc and lex sources). This
4452 greatly improves GDB's ability to find yacc/lex sources, and include files,
4453 especially if you are debugging your program from a directory different from
4454 the one that contains your sources.
4456 We also fixed a bug which caused difficulty with listing and setting
4457 breakpoints in include files which contain C code. (In the past, you had to
4458 try twice in order to list an include file that you hadn't looked at before.)
4460 * Interesting infernals change
4462 GDB now deals with arbitrary numbers of sections, where the symbols for each
4463 section must be relocated relative to that section's landing place in the
4464 target's address space. This work was needed to support ELF with embedded
4465 stabs used by Solaris-2.0.
4467 * Bug fixes (of course!)
4469 There have been loads of fixes for the following things:
4470 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4471 i960, stabs, DOS(GO32), procfs, etc...
4473 See the ChangeLog for details.
4475 *** Changes in GDB-4.5:
4477 * New machines supported (host and target)
4479 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4481 SGI Irix-4.x mips-sgi-irix4 or iris4
4483 * New malloc package
4485 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4486 Mmalloc is capable of handling mutiple heaps of memory. It is also
4487 capable of saving a heap to a file, and then mapping it back in later.
4488 This can be used to greatly speedup the startup of GDB by using a
4489 pre-parsed symbol table which lives in a mmalloc managed heap. For
4490 more details, please read mmalloc/mmalloc.texi.
4494 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4495 'help info proc' for details.
4497 * MIPS ecoff symbol table format
4499 The code that reads MIPS symbol table format is now supported on all hosts.
4500 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4503 * File name changes for MS-DOS
4505 Many files in the config directories have been renamed to make it easier to
4506 support GDB on MS-DOSe systems (which have very restrictive file name
4507 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4508 environment) is close to working but has some remaining problems. Note
4509 that debugging of DOS programs is not supported, due to limitations
4510 in the ``operating system'', but it can be used to host cross-debugging.
4512 * Cross byte order fixes
4514 Many fixes have been made to support cross debugging of Sparc and MIPS
4515 targets from hosts whose byte order differs.
4517 * New -mapped and -readnow options
4519 If memory-mapped files are available on your system through the 'mmap'
4520 system call, you can use the -mapped option on the `file' or
4521 `symbol-file' commands to cause GDB to write the symbols from your
4522 program into a reusable file. If the program you are debugging is
4523 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4524 Future GDB debugging sessions will notice the presence of this file,
4525 and will quickly map in symbol information from it, rather than reading
4526 the symbol table from the executable program. Using the '-mapped'
4527 option in a GDB `file' or `symbol-file' command has the same effect as
4528 starting GDB with the '-mapped' command-line option.
4530 You can cause GDB to read the entire symbol table immediately by using
4531 the '-readnow' option with any of the commands that load symbol table
4532 information (or on the GDB command line). This makes the command
4533 slower, but makes future operations faster.
4535 The -mapped and -readnow options are typically combined in order to
4536 build a `fred.syms' file that contains complete symbol information.
4537 A simple GDB invocation to do nothing but build a `.syms' file for future
4540 gdb -batch -nx -mapped -readnow programname
4542 The `.syms' file is specific to the host machine on which GDB is run.
4543 It holds an exact image of GDB's internal symbol table. It cannot be
4544 shared across multiple host platforms.
4546 * longjmp() handling
4548 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4549 siglongjmp() without losing control. This feature has not yet been ported to
4550 all systems. It currently works on many 386 platforms, all MIPS-based
4551 platforms (SGI, DECstation, etc), and Sun3/4.
4555 Preliminary work has been put in to support the new Solaris OS from Sun. At
4556 this time, it can control and debug processes, but it is not capable of
4561 As always, many many bug fixes. The major areas were with g++, and mipsread.
4562 People using the MIPS-based platforms should experience fewer mysterious
4563 crashes and trashed symbol tables.
4565 *** Changes in GDB-4.4:
4567 * New machines supported (host and target)
4569 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4571 BSD Reno on Vax vax-dec-bsd
4572 Ultrix on Vax vax-dec-ultrix
4574 * New machines supported (target)
4576 AMD 29000 embedded, using EBMON a29k-none-none
4580 GDB continues to improve its handling of C++. `References' work better.
4581 The demangler has also been improved, and now deals with symbols mangled as
4582 per the Annotated C++ Reference Guide.
4584 GDB also now handles `stabs' symbol information embedded in MIPS
4585 `ecoff' symbol tables. Since the ecoff format was not easily
4586 extensible to handle new languages such as C++, this appeared to be a
4587 good way to put C++ debugging info into MIPS binaries. This option
4588 will be supported in the GNU C compiler, version 2, when it is
4591 * New features for SVR4
4593 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4594 shared libraries. Debugging dynamically linked programs should present
4595 only minor differences from debugging statically linked programs.
4597 The `info proc' command will print out information about any process
4598 on an SVR4 system (including the one you are debugging). At the moment,
4599 it prints the address mappings of the process.
4601 If you bring up GDB on another SVR4 system, please send mail to
4602 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4604 * Better dynamic linking support in SunOS
4606 Reading symbols from shared libraries which contain debugging symbols
4607 now works properly. However, there remain issues such as automatic
4608 skipping of `transfer vector' code during function calls, which
4609 make it harder to debug code in a shared library, than to debug the
4610 same code linked statically.
4614 GDB is now using the latest `getopt' routines from the FSF. This
4615 version accepts the -- prefix for options with long names. GDB will
4616 continue to accept the old forms (-option and +option) as well.
4617 Various single letter abbreviations for options have been explicity
4618 added to the option table so that they won't get overshadowed in the
4619 future by other options that begin with the same letter.
4623 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4624 Many assorted bugs have been handled. Many more remain to be handled.
4625 See the various ChangeLog files (primarily in gdb and bfd) for details.
4628 *** Changes in GDB-4.3:
4630 * New machines supported (host and target)
4632 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4633 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4634 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4636 * Almost SCO Unix support
4638 We had hoped to support:
4639 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4640 (except for core file support), but we discovered very late in the release
4641 that it has problems with process groups that render gdb unusable. Sorry
4642 about that. I encourage people to fix it and post the fixes.
4644 * Preliminary ELF and DWARF support
4646 GDB can read ELF object files on System V Release 4, and can handle
4647 debugging records for C, in DWARF format, in ELF files. This support
4648 is preliminary. If you bring up GDB on another SVR4 system, please
4649 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4654 GDB now uses the latest `readline' library. One user-visible change
4655 is that two tabs will list possible command completions, which previously
4656 required typing M-? (meta-question mark, or ESC ?).
4660 The `stepi' bug that many of you noticed has been squashed.
4661 Many bugs in C++ have been handled. Many more remain to be handled.
4662 See the various ChangeLog files (primarily in gdb and bfd) for details.
4664 * State of the MIPS world (in case you wondered):
4666 GDB can understand the symbol tables emitted by the compilers
4667 supplied by most vendors of MIPS-based machines, including DEC. These
4668 symbol tables are in a format that essentially nobody else uses.
4670 Some versions of gcc come with an assembler post-processor called
4671 mips-tfile. This program is required if you want to do source-level
4672 debugging of gcc-compiled programs. I believe FSF does not ship
4673 mips-tfile with gcc version 1, but it will eventually come with gcc
4676 Debugging of g++ output remains a problem. g++ version 1.xx does not
4677 really support it at all. (If you're lucky, you should be able to get
4678 line numbers and stack traces to work, but no parameters or local
4679 variables.) With some work it should be possible to improve the
4682 When gcc version 2 is released, you will have somewhat better luck.
4683 However, even then you will get confusing results for inheritance and
4686 We will eventually provide full debugging of g++ output on
4687 DECstations. This will probably involve some kind of stabs-in-ecoff
4688 encapulation, but the details have not been worked out yet.
4691 *** Changes in GDB-4.2:
4693 * Improved configuration
4695 Only one copy of `configure' exists now, and it is not self-modifying.
4696 Porting BFD is simpler.
4700 The `step' and `next' commands now only stop at the first instruction
4701 of a source line. This prevents the multiple stops that used to occur
4702 in switch statements, for-loops, etc. `Step' continues to stop if a
4703 function that has debugging information is called within the line.
4707 Lots of small bugs fixed. More remain.
4709 * New host supported (not target)
4711 Intel 386 PC clone running Mach i386-none-mach
4714 *** Changes in GDB-4.1:
4716 * Multiple source language support
4718 GDB now has internal scaffolding to handle several source languages.
4719 It determines the type of each source file from its filename extension,
4720 and will switch expression parsing and number formatting to match the
4721 language of the function in the currently selected stack frame.
4722 You can also specifically set the language to be used, with
4723 `set language c' or `set language modula-2'.
4727 GDB now has preliminary support for the GNU Modula-2 compiler,
4728 currently under development at the State University of New York at
4729 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4730 continue through the fall of 1991 and into 1992.
4732 Other Modula-2 compilers are currently not supported, and attempting to
4733 debug programs compiled with them will likely result in an error as the
4734 symbol table is read. Feel free to work on it, though!
4736 There are hooks in GDB for strict type checking and range checking,
4737 in the `Modula-2 philosophy', but they do not currently work.
4741 GDB can now write to executable and core files (e.g. patch
4742 a variable's value). You must turn this switch on, specify
4743 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4744 by assigning a new value to a variable. Modifications take
4747 * Automatic SunOS shared library reading
4749 When you run your program, GDB automatically determines where its
4750 shared libraries (if any) have been loaded, and reads their symbols.
4751 The `share' command is no longer needed. This also works when
4752 examining core files.
4756 You can specify the number of lines that the `list' command shows.
4759 * New machines supported (host and target)
4761 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4762 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4763 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4765 * New hosts supported (not targets)
4767 IBM RT/PC: romp-ibm-aix or rtpc
4769 * New targets supported (not hosts)
4771 AMD 29000 embedded with COFF a29k-none-coff
4772 AMD 29000 embedded with a.out a29k-none-aout
4773 Ultracomputer remote kernel debug a29k-nyu-kern
4775 * New remote interfaces
4781 *** Changes in GDB-4.0:
4785 Wide output is wrapped at good places to make the output more readable.
4787 Gdb now supports cross-debugging from a host machine of one type to a
4788 target machine of another type. Communication with the target system
4789 is over serial lines. The ``target'' command handles connecting to the
4790 remote system; the ``load'' command will download a program into the
4791 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4792 also supports debugging of realtime processes running under VxWorks,
4793 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4794 stub on the target system.
4796 New CPUs supported include the AMD 29000 and Intel 960.
4798 GDB now reads object files and symbol tables via a ``binary file''
4799 library, which allows a single copy of GDB to debug programs of multiple
4800 object file types such as a.out and coff.
4802 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4803 refcard.dvi and refcard.ps are available to format it).
4806 * Control-Variable user interface simplified
4808 All variables that control the operation of the debugger can be set
4809 by the ``set'' command, and displayed by the ``show'' command.
4811 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4812 ``Show prompt'' produces the response:
4813 Gdb's prompt is new-gdb=>.
4815 What follows are the NEW set commands. The command ``help set'' will
4816 print a complete list of old and new set commands. ``help set FOO''
4817 will give a longer description of the variable FOO. ``show'' will show
4818 all of the variable descriptions and their current settings.
4820 confirm on/off: Enables warning questions for operations that are
4821 hard to recover from, e.g. rerunning the program while
4822 it is already running. Default is ON.
4824 editing on/off: Enables EMACS style command line editing
4825 of input. Previous lines can be recalled with
4826 control-P, the current line can be edited with control-B,
4827 you can search for commands with control-R, etc.
4830 history filename NAME: NAME is where the gdb command history
4831 will be stored. The default is .gdb_history,
4832 or the value of the environment variable
4835 history size N: The size, in commands, of the command history. The
4836 default is 256, or the value of the environment variable
4839 history save on/off: If this value is set to ON, the history file will
4840 be saved after exiting gdb. If set to OFF, the
4841 file will not be saved. The default is OFF.
4843 history expansion on/off: If this value is set to ON, then csh-like
4844 history expansion will be performed on
4845 command line input. The default is OFF.
4847 radix N: Sets the default radix for input and output. It can be set
4848 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4849 in the current radix, so "set radix 10" is always a no-op.
4851 height N: This integer value is the number of lines on a page. Default
4852 is 24, the current `stty rows'' setting, or the ``li#''
4853 setting from the termcap entry matching the environment
4856 width N: This integer value is the number of characters on a line.
4857 Default is 80, the current `stty cols'' setting, or the ``co#''
4858 setting from the termcap entry matching the environment
4861 Note: ``set screensize'' is obsolete. Use ``set height'' and
4862 ``set width'' instead.
4864 print address on/off: Print memory addresses in various command displays,
4865 such as stack traces and structure values. Gdb looks
4866 more ``symbolic'' if you turn this off; it looks more
4867 ``machine level'' with it on. Default is ON.
4869 print array on/off: Prettyprint arrays. New convenient format! Default
4872 print demangle on/off: Print C++ symbols in "source" form if on,
4875 print asm-demangle on/off: Same, for assembler level printouts
4878 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4881 * Support for Epoch Environment.
4883 The epoch environment is a version of Emacs v18 with windowing. One
4884 new command, ``inspect'', is identical to ``print'', except that if you
4885 are running in the epoch environment, the value is printed in its own
4889 * Support for Shared Libraries
4891 GDB can now debug programs and core files that use SunOS shared libraries.
4892 Symbols from a shared library cannot be referenced
4893 before the shared library has been linked with the program (this
4894 happens after you type ``run'' and before the function main() is entered).
4895 At any time after this linking (including when examining core files
4896 from dynamically linked programs), gdb reads the symbols from each
4897 shared library when you type the ``sharedlibrary'' command.
4898 It can be abbreviated ``share''.
4900 sharedlibrary REGEXP: Load shared object library symbols for files
4901 matching a unix regular expression. No argument
4902 indicates to load symbols for all shared libraries.
4904 info sharedlibrary: Status of loaded shared libraries.
4909 A watchpoint stops execution of a program whenever the value of an
4910 expression changes. Checking for this slows down execution
4911 tremendously whenever you are in the scope of the expression, but is
4912 quite useful for catching tough ``bit-spreader'' or pointer misuse
4913 problems. Some machines such as the 386 have hardware for doing this
4914 more quickly, and future versions of gdb will use this hardware.
4916 watch EXP: Set a watchpoint (breakpoint) for an expression.
4918 info watchpoints: Information about your watchpoints.
4920 delete N: Deletes watchpoint number N (same as breakpoints).
4921 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4922 enable N: Re-enables watchpoint number N (same as breakpoints).
4925 * C++ multiple inheritance
4927 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4930 * C++ exception handling
4932 Gdb now supports limited C++ exception handling. Besides the existing
4933 ability to breakpoint on an exception handler, gdb can breakpoint on
4934 the raising of an exception (before the stack is peeled back to the
4937 catch FOO: If there is a FOO exception handler in the dynamic scope,
4938 set a breakpoint to catch exceptions which may be raised there.
4939 Multiple exceptions (``catch foo bar baz'') may be caught.
4941 info catch: Lists all exceptions which may be caught in the
4942 current stack frame.
4945 * Minor command changes
4947 The command ``call func (arg, arg, ...)'' now acts like the print
4948 command, except it does not print or save a value if the function's result
4949 is void. This is similar to dbx usage.
4951 The ``up'' and ``down'' commands now always print the frame they end up
4952 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4953 frames without printing.
4955 * New directory command
4957 'dir' now adds directories to the FRONT of the source search path.
4958 The path starts off empty. Source files that contain debug information
4959 about the directory in which they were compiled can be found even
4960 with an empty path; Sun CC and GCC include this information. If GDB can't
4961 find your source file in the current directory, type "dir .".
4963 * Configuring GDB for compilation
4965 For normal use, type ``./configure host''. See README or gdb.texinfo
4968 GDB now handles cross debugging. If you are remotely debugging between
4969 two different machines, type ``./configure host -target=targ''.
4970 Host is the machine where GDB will run; targ is the machine
4971 where the program that you are debugging will run.