1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
6 * GDB now supports reversible debugging on ARM, it allows you to
7 debug basic ARM and THUMB instructions, and provides
10 * The option "symbol-reloading" has been deleted as it is no longer used.
14 ** GDB commands implemented in Python can now be put in command class
17 ** The "maint set python print-stack on|off" is now deleted.
19 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
20 apply "flag enum"-style pretty-printing to any enum.
22 ** gdb.lookup_symbol can now work when there is no current frame.
24 ** gdb.Symbol now has a 'line' attribute, holding the line number in
25 the source at which the symbol was defined.
27 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
28 method 'value'. The former indicates whether the symbol needs a
29 frame in order to compute its value, and the latter computes the
32 ** A new method 'referenced_value' on gdb.Value objects which can
33 dereference pointer as well as C++ reference values.
35 * GDBserver now supports stdio connections.
36 E.g. (gdb) target remote | ssh myhost gdbserver - hello
38 * The binary "gdbtui" can no longer be built or installed.
39 Use "gdb -tui" instead.
41 * GDB will now print "flag" enums specially. A flag enum is one where
42 all the enumerator values have no bits in common when pairwise
43 "and"ed. When printing a value whose type is a flag enum, GDB will
44 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
45 (gdb) print (enum E) 3
48 * The filename part of a linespec will now match trailing components
49 of a source file name. For example, "break gcc/expr.c:1000" will
50 now set a breakpoint in build/gcc/expr.c, but not
53 * The "info proc" and "generate-core-file" commands will now also
54 work on remote targets connected to GDBserver on Linux.
56 * The command "info catch" has been removed. It has been disabled
59 * The "catch exception" and "catch assert" commands now accept
60 a condition at the end of the command, much like the "break"
61 command does. For instance:
63 (gdb) catch exception Constraint_Error if Barrier = True
65 Previously, it was possible to add a condition to such catchpoints,
66 but it had to be done as a second step, after the catchpoint had been
67 created, using the "condition" command.
69 * The "info static-tracepoint-marker" command will now also work on
70 native Linux targets with in-process agent.
72 * GDB can now set breakpoints on inlined functions.
74 * The .gdb_index section has been updated to include symbols for
75 inlined functions. GDB will ignore older .gdb_index sections by
76 default, which could cause symbol files to be loaded more slowly
77 until their .gdb_index sections can be recreated. The new option
78 --use-deprecated-index-sections will cause GDB to use any older
79 .gdb_index sections it finds. This will restore performance, but
80 the ability to set breakpoints on inlined functions will be lost
81 in symbol files with older .gdb_index sections.
83 * Ada support for GDB/MI Variable Objects has been added.
87 ** "catch load" and "catch unload" can be used to stop when a shared
88 library is loaded or unloaded, respectively.
90 ** "enable count" can be used to auto-disable a breakpoint after
93 ** "info vtbl" can be used to show the virtual method tables for
96 ** "explore" and its sub commands "explore value" and "explore type"
97 can be used to reccursively explore values and types of
98 expressions. These commands are available only if GDB is
99 configured with '--with-python'.
101 ** "info auto-load" shows status of all kinds of auto-loaded files,
102 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
103 sequences of commands files, "info auto-load python-scripts"
104 shows status of auto-loading Python script files,
105 "info auto-load local-gdbinit" shows status of loading init file
106 (.gdbinit) from current directory and "info auto-load libthread-db" shows
107 status of inferior specific thread debugging shared library loading.
109 ** "info auto-load-scripts", "set auto-load-scripts on|off"
110 and "show auto-load-scripts" commands have been deprecated, use their
111 "info auto-load python-scripts", "set auto-load python-scripts on|off"
112 and "show auto-load python-scripts" counterparts instead.
116 Renesas RL78 rl78-*-elf
117 HP OpenVMS ia64 ia64-hp-openvms*
119 * GDBserver supports evaluation of breakpoint conditions. When
120 support is advertised by GDBserver, GDB may be told to send the
121 breakpoint conditions in bytecode form to GDBserver. GDBserver
122 will only report the breakpoint trigger to GDB when its condition
127 set breakpoint condition-evaluation
128 show breakpoint condition-evaluation
129 Control whether breakpoint conditions are evaluated by GDB ("host") or by
130 GDBserver ("target"). Default option "auto" chooses the most efficient
132 This option can improve debugger efficiency depending on the speed of the
136 Disable auto-loading globally.
139 Show auto-loading setting of all kinds of auto-loaded files.
141 set auto-load gdb-scripts on|off
142 show auto-load gdb-scripts
143 Control auto-loading of GDB canned sequences of commands files.
145 set auto-load python-scripts on|off
146 show auto-load python-scripts
147 Control auto-loading of Python script files.
149 set auto-load local-gdbinit on|off
150 show auto-load local-gdbinit
151 Control loading of init file (.gdbinit) from current directory.
153 set auto-load libthread-db on|off
154 show auto-load libthread-db
155 Control auto-loading of inferior specific thread debugging shared library.
157 set auto-load safe-path <dir1>[:<dir2>...]
158 show auto-load safe-path
159 Set a list of directories from which it is safe to auto-load files.
160 The delimiter (':' above) may differ according to the host platform.
162 set debug auto-load on|off
164 Control display of debugging info for auto-loading the files above.
168 z0/z1 conditional breakpoints extension
170 The z0/z1 breakpoint insertion packets have been extended to carry
171 a list of conditional expressions over to the remote stub depending on the
172 condition evaluation mode. The use of this extension can be controlled
173 via the "set remote conditional-breakpoints-packet" command.
177 Specify the signals which the remote stub may pass to the debugged
178 program without GDB involvement.
180 * New command line options
182 --init-command=FILE, -ix Like --command, -x but execute it
183 before loading inferior.
184 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
185 execute it before loading inferior.
187 *** Changes in GDB 7.4
189 * GDB now handles ambiguous linespecs more consistently; the existing
190 FILE:LINE support has been expanded to other types of linespecs. A
191 breakpoint will now be set on all matching locations in all
192 inferiors, and locations will be added or removed according to
195 * GDB now allows you to skip uninteresting functions and files when
196 stepping with the "skip function" and "skip file" commands.
198 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
199 and "show remote hardware-watchpoint-length-limit". These allows to
200 set or show the maximum length limit (in bytes) of a remote
201 target hardware watchpoint.
203 This allows e.g. to use "unlimited" hardware watchpoints with the
204 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
205 watchpoints are slower than real hardware watchpoints but are
206 significantly faster than gdb software watchpoints.
210 ** The register_pretty_printer function in module gdb.printing now takes
211 an optional `replace' argument. If True, the new printer replaces any
214 ** The "maint set python print-stack on|off" command has been
215 deprecated and will be deleted in GDB 7.5.
216 A new command: "set python print-stack none|full|message" has
217 replaced it. Additionally, the default for "print-stack" is
218 now "message", which just prints the error message without
221 ** A prompt substitution hook (prompt_hook) is now available to the
224 ** A new Python module, gdb.prompt has been added to the GDB Python
225 modules library. This module provides functionality for
226 escape sequences in prompts (used by set/show
227 extended-prompt). These escape sequences are replaced by their
230 ** Python commands and convenience-functions located in
231 'data-directory'/python/gdb/command and
232 'data-directory'/python/gdb/function are now automatically loaded
235 ** Blocks now provide four new attributes. global_block and
236 static_block will return the global and static blocks
237 respectively. is_static and is_global are boolean attributes
238 that indicate if the block is one of those two types.
240 ** Symbols now provide the "type" attribute, the type of the symbol.
242 ** The "gdb.breakpoint" function has been deprecated in favor of
245 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
246 of a function. This class is based on the "finish" command
247 available in the CLI.
249 ** Type objects for struct and union types now allow access to
250 the fields using standard Python dictionary (mapping) methods.
251 For example, "some_type['myfield']" now works, as does
254 ** A new event "gdb.new_objfile" has been added, triggered by loading a
257 ** A new function, "deep_items" has been added to the gdb.types
258 module in the GDB Python modules library. This function returns
259 an iterator over the fields of a struct or union type. Unlike
260 the standard Python "iteritems" method, it will recursively traverse
261 any anonymous fields.
265 ** "*stopped" events can report several new "reason"s, such as
268 ** Breakpoint changes are now notified using new async records, like
269 "=breakpoint-modified".
271 ** New command -ada-task-info.
273 * libthread-db-search-path now supports two special values: $sdir and $pdir.
274 $sdir specifies the default system locations of shared libraries.
275 $pdir specifies the directory where the libpthread used by the application
278 GDB no longer looks in $sdir and $pdir after it has searched the directories
279 mentioned in libthread-db-search-path. If you want to search those
280 directories, they must be specified in libthread-db-search-path.
281 The default value of libthread-db-search-path on GNU/Linux and Solaris
282 systems is now "$sdir:$pdir".
284 $pdir is not supported by gdbserver, it is currently ignored.
285 $sdir is supported by gdbserver.
287 * New configure option --with-iconv-bin.
288 When using the internationalization support like the one in the GNU C
289 library, GDB will invoke the "iconv" program to get a list of supported
290 character sets. If this program lives in a non-standard location, one can
291 use this option to specify where to find it.
293 * When natively debugging programs on PowerPC BookE processors running
294 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
295 watchpoints, which specify a mask in addition to an address to watch.
296 The mask specifies that some bits of an address (the bits which are
297 reset in the mask) should be ignored when matching the address accessed
298 by the inferior against the watchpoint address. See the "PowerPC Embedded"
299 section in the user manual for more details.
301 * The new option --once causes GDBserver to stop listening for connections once
302 the first connection is made. The listening port used by GDBserver will
303 become available after that.
305 * New commands "info macros" and "alias" have been added.
307 * New function parameters suffix @entry specifies value of function parameter
308 at the time the function got called. Entry values are available only since
314 "!" is now an alias of the "shell" command.
315 Note that no space is needed between "!" and SHELL COMMAND.
319 watch EXPRESSION mask MASK_VALUE
320 The watch command now supports the mask argument which allows creation
321 of masked watchpoints, if the current architecture supports this feature.
323 info auto-load-scripts [REGEXP]
324 This command was formerly named "maintenance print section-scripts".
325 It is now generally useful and is no longer a maintenance-only command.
327 info macro [-all] [--] MACRO
328 The info macro command has new options `-all' and `--'. The first for
329 printing all definitions of a macro. The second for explicitly specifying
330 the end of arguments and the beginning of the macro name in case the macro
331 name starts with a hyphen.
333 collect[/s] EXPRESSIONS
334 The tracepoint collect command now takes an optional modifier "/s"
335 that directs it to dereference pointer-to-character types and
336 collect the bytes of memory up to a zero byte. The behavior is
337 similar to what you see when you use the regular print command on a
338 string. An optional integer following the "/s" sets a bound on the
339 number of bytes that will be collected.
342 The trace start command now interprets any supplied arguments as a
343 note to be recorded with the trace run, with an effect similar to
344 setting the variable trace-notes.
347 The trace stop command now interprets any arguments as a note to be
348 mentioned along with the tstatus report that the trace was stopped
349 with a command. The effect is similar to setting the variable
352 * Tracepoints can now be enabled and disabled at any time after a trace
353 experiment has been started using the standard "enable" and "disable"
354 commands. It is now possible to start a trace experiment with no enabled
355 tracepoints; GDB will display a warning, but will allow the experiment to
356 begin, assuming that tracepoints will be enabled as needed while the trace
359 * Fast tracepoints on 32-bit x86-architectures can now be placed at
360 locations with 4-byte instructions, when they were previously
361 limited to locations with instructions of 5 bytes or longer.
367 Set the GDB prompt, and allow escape sequences to be inserted to
368 display miscellaneous information (see 'help set extended-prompt'
369 for the list of sequences). This prompt (and any information
370 accessed through the escape sequences) is updated every time the
373 set print entry-values (both|compact|default|if-needed|no|only|preferred)
374 show print entry-values
375 Set printing of frame argument values at function entry. In some cases
376 GDB can determine the value of function argument which was passed by the
377 function caller, even if the value was modified inside the called function.
379 set debug entry-values
380 show debug entry-values
381 Control display of debugging info for determining frame argument values at
382 function entry and virtual tail call frames.
384 set basenames-may-differ
385 show basenames-may-differ
386 Set whether a source file may have multiple base names.
387 (A "base name" is the name of a file with the directory part removed.
388 Example: The base name of "/home/user/hello.c" is "hello.c".)
389 If set, GDB will canonicalize file names (e.g., expand symlinks)
390 before comparing them. Canonicalization is an expensive operation,
391 but it allows the same file be known by more than one base name.
392 If not set (the default), all source files are assumed to have just
393 one base name, and gdb will do file name comparisons more efficiently.
399 Set a user name and notes for the current and any future trace runs.
400 This is useful for long-running and/or disconnected traces, to
401 inform others (or yourself) as to who is running the trace, supply
402 contact information, or otherwise explain what is going on.
405 show trace-stop-notes
406 Set a note attached to the trace run, that is displayed when the
407 trace has been stopped by a tstop command. This is useful for
408 instance as an explanation, if you are stopping a trace run that was
409 started by someone else.
415 Dynamically enable a tracepoint in a started trace experiment.
419 Dynamically disable a tracepoint in a started trace experiment.
423 Set the user and notes of the trace run.
427 Query the current status of a tracepoint.
431 Query the minimum length of instruction at which a fast tracepoint may
434 * Dcache size (number of lines) and line-size are now runtime-configurable
435 via "set dcache line" and "set dcache line-size" commands.
439 Texas Instruments TMS320C6x tic6x-*-*
443 Renesas RL78 rl78-*-elf
445 *** Changes in GDB 7.3.1
447 * The build failure for NetBSD and OpenBSD targets have now been fixed.
449 *** Changes in GDB 7.3
451 * GDB has a new command: "thread find [REGEXP]".
452 It finds the thread id whose name, target id, or thread extra info
453 matches the given regular expression.
455 * The "catch syscall" command now works on mips*-linux* targets.
457 * The -data-disassemble MI command now supports modes 2 and 3 for
458 dumping the instruction opcodes.
460 * New command line options
462 -data-directory DIR Specify DIR as the "data-directory".
463 This is mostly for testing purposes.
465 * The "maint set python auto-load on|off" command has been renamed to
466 "set auto-load-scripts on|off".
468 * GDB has a new command: "set directories".
469 It is like the "dir" command except that it replaces the
470 source path list instead of augmenting it.
472 * GDB now understands thread names.
474 On GNU/Linux, "info threads" will display the thread name as set by
475 prctl or pthread_setname_np.
477 There is also a new command, "thread name", which can be used to
478 assign a name internally for GDB to display.
481 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
482 has been integrated into GDB.
486 ** The function gdb.Write now accepts an optional keyword 'stream'.
487 This keyword, when provided, will direct the output to either
488 stdout, stderr, or GDB's logging output.
490 ** Parameters can now be be sub-classed in Python, and in particular
491 you may implement the get_set_doc and get_show_doc functions.
492 This improves how Parameter set/show documentation is processed
493 and allows for more dynamic content.
495 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
496 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
497 have an is_valid method.
499 ** Breakpoints can now be sub-classed in Python, and in particular
500 you may implement a 'stop' function that is executed each time
501 the inferior reaches that breakpoint.
503 ** New function gdb.lookup_global_symbol looks up a global symbol.
505 ** GDB values in Python are now callable if the value represents a
506 function. For example, if 'some_value' represents a function that
507 takes two integer parameters and returns a value, you can call
508 that function like so:
510 result = some_value (10,20)
512 ** Module gdb.types has been added.
513 It contains a collection of utilities for working with gdb.Types objects:
514 get_basic_type, has_field, make_enum_dict.
516 ** Module gdb.printing has been added.
517 It contains utilities for writing and registering pretty-printers.
518 New classes: PrettyPrinter, SubPrettyPrinter,
519 RegexpCollectionPrettyPrinter.
520 New function: register_pretty_printer.
522 ** New commands "info pretty-printers", "enable pretty-printer" and
523 "disable pretty-printer" have been added.
525 ** gdb.parameter("directories") is now available.
527 ** New function gdb.newest_frame returns the newest frame in the
530 ** The gdb.InferiorThread class has a new "name" attribute. This
531 holds the thread's name.
533 ** Python Support for Inferior events.
534 Python scripts can add observers to be notified of events
535 occurring in the process being debugged.
536 The following events are currently supported:
537 - gdb.events.cont Continue event.
538 - gdb.events.exited Inferior exited event.
539 - gdb.events.stop Signal received, and Breakpoint hit events.
543 ** GDB now puts template parameters in scope when debugging in an
544 instantiation. For example, if you have:
546 template<int X> int func (void) { return X; }
548 then if you step into func<5>, "print X" will show "5". This
549 feature requires proper debuginfo support from the compiler; it
550 was added to GCC 4.5.
552 ** The motion commands "next", "finish", "until", and "advance" now
553 work better when exceptions are thrown. In particular, GDB will
554 no longer lose control of the inferior; instead, the GDB will
555 stop the inferior at the point at which the exception is caught.
556 This functionality requires a change in the exception handling
557 code that was introduced in GCC 4.5.
559 * GDB now follows GCC's rules on accessing volatile objects when
560 reading or writing target state during expression evaluation.
561 One notable difference to prior behavior is that "print x = 0"
562 no longer generates a read of x; the value of the assignment is
563 now always taken directly from the value being assigned.
565 * GDB now has some support for using labels in the program's source in
566 linespecs. For instance, you can use "advance label" to continue
567 execution to a label.
569 * GDB now has support for reading and writing a new .gdb_index
570 section. This section holds a fast index of DWARF debugging
571 information and can be used to greatly speed up GDB startup and
572 operation. See the documentation for `save gdb-index' for details.
574 * The "watch" command now accepts an optional "-location" argument.
575 When used, this causes GDB to watch the memory referred to by the
576 expression. Such a watchpoint is never deleted due to it going out
579 * GDB now supports thread debugging of core dumps on GNU/Linux.
581 GDB now activates thread debugging using the libthread_db library
582 when debugging GNU/Linux core dumps, similarly to when debugging
583 live processes. As a result, when debugging a core dump file, GDB
584 is now able to display pthread_t ids of threads. For example, "info
585 threads" shows the same output as when debugging the process when it
586 was live. In earlier releases, you'd see something like this:
589 * 1 LWP 6780 main () at main.c:10
591 While now you see this:
594 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
596 It is also now possible to inspect TLS variables when debugging core
599 When debugging a core dump generated on a machine other than the one
600 used to run GDB, you may need to point GDB at the correct
601 libthread_db library with the "set libthread-db-search-path"
602 command. See the user manual for more details on this command.
604 * When natively debugging programs on PowerPC BookE processors running
605 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
606 which stop execution of the inferior whenever it executes an instruction
607 at any address within the specified range. See the "PowerPC Embedded"
608 section in the user manual for more details.
610 * New features in the GDB remote stub, GDBserver
612 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
613 and i686 LynxOS (version 5.x).
615 ** GDBserver is now supported on Blackfin Linux.
617 * New native configurations
619 ia64 HP-UX ia64-*-hpux*
623 Analog Devices, Inc. Blackfin Processor bfin-*
625 * Ada task switching is now supported on sparc-elf targets when
626 debugging a program using the Ravenscar Profile. For more information,
627 see the "Tasking Support when using the Ravenscar Profile" section
628 in the GDB user manual.
630 * Guile support was removed.
632 * New features in the GNU simulator
634 ** The --map-info flag lists all known core mappings.
636 ** CFI flashes may be simulated via the "cfi" device.
638 *** Changes in GDB 7.2
640 * Shared library support for remote targets by default
642 When GDB is configured for a generic, non-OS specific target, like
643 for example, --target=arm-eabi or one of the many *-*-elf targets,
644 GDB now queries remote stubs for loaded shared libraries using the
645 `qXfer:libraries:read' packet. Previously, shared library support
646 was always disabled for such configurations.
650 ** Argument Dependent Lookup (ADL)
652 In C++ ADL lookup directs function search to the namespaces of its
653 arguments even if the namespace has not been imported.
663 Here the compiler will search for `foo' in the namespace of 'b'
664 and find A::foo. GDB now supports this. This construct is commonly
665 used in the Standard Template Library for operators.
667 ** Improved User Defined Operator Support
669 In addition to member operators, GDB now supports lookup of operators
670 defined in a namespace and imported with a `using' directive, operators
671 defined in the global scope, operators imported implicitly from an
672 anonymous namespace, and the ADL operators mentioned in the previous
674 GDB now also supports proper overload resolution for all the previously
675 mentioned flavors of operators.
677 ** static const class members
679 Printing of static const class members that are initialized in the
680 class definition has been fixed.
682 * Windows Thread Information Block access.
684 On Windows targets, GDB now supports displaying the Windows Thread
685 Information Block (TIB) structure. This structure is visible either
686 by using the new command `info w32 thread-information-block' or, by
687 dereferencing the new convenience variable named `$_tlb', a
688 thread-specific pointer to the TIB. This feature is also supported
689 when remote debugging using GDBserver.
693 Static tracepoints are calls in the user program into a tracing
694 library. One such library is a port of the LTTng kernel tracer to
695 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
696 When debugging with GDBserver, GDB now supports combining the GDB
697 tracepoint machinery with such libraries. For example: the user can
698 use GDB to probe a static tracepoint marker (a call from the user
699 program into the tracing library) with the new "strace" command (see
700 "New commands" below). This creates a "static tracepoint" in the
701 breakpoint list, that can be manipulated with the same feature set
702 as fast and regular tracepoints. E.g., collect registers, local and
703 global variables, collect trace state variables, and define
704 tracepoint conditions. In addition, the user can collect extra
705 static tracepoint marker specific data, by collecting the new
706 $_sdata internal variable. When analyzing the trace buffer, you can
707 inspect $_sdata like any other variable available to GDB. For more
708 information, see the "Tracepoints" chapter in GDB user manual. New
709 remote packets have been defined to support static tracepoints, see
710 the "New remote packets" section below.
712 * Better reconstruction of tracepoints after disconnected tracing
714 GDB will attempt to download the original source form of tracepoint
715 definitions when starting a trace run, and then will upload these
716 upon reconnection to the target, resulting in a more accurate
717 reconstruction of the tracepoints that are in use on the target.
721 You can now exercise direct control over the ways that GDB can
722 affect your program. For instance, you can disallow the setting of
723 breakpoints, so that the program can run continuously (assuming
724 non-stop mode). In addition, the "observer" variable is available
725 to switch all of the different controls; in observer mode, GDB
726 cannot affect the target's behavior at all, which is useful for
727 tasks like diagnosing live systems in the field.
729 * The new convenience variable $_thread holds the number of the
736 Return the address of the Windows Thread Information Block of a given thread.
740 In response to several of the tracepoint packets, the target may now
741 also respond with a number of intermediate `qRelocInsn' request
742 packets before the final result packet, to have GDB handle
743 relocating an instruction to execute at a different address. This
744 is particularly useful for stubs that support fast tracepoints. GDB
745 reports support for this feature in the qSupported packet.
749 List static tracepoint markers in the target program.
753 List static tracepoint markers at a given address in the target
756 qXfer:statictrace:read
758 Read the static trace data collected (by a `collect $_sdata'
759 tracepoint action). The remote stub reports support for this packet
760 to gdb's qSupported query.
764 Send the current settings of GDB's permission flags.
768 Send part of the source (textual) form of a tracepoint definition,
769 which includes location, conditional, and action list.
771 * The source command now accepts a -s option to force searching for the
772 script in the source search path even if the script name specifies
775 * New features in the GDB remote stub, GDBserver
777 - GDBserver now support tracepoints (including fast tracepoints, and
778 static tracepoints). The feature is currently supported by the
779 i386-linux and amd64-linux builds. See the "Tracepoints support
780 in gdbserver" section in the manual for more information.
782 GDBserver JIT compiles the tracepoint's conditional agent
783 expression bytecode into native code whenever possible for low
784 overhead dynamic tracepoints conditionals. For such tracepoints,
785 an expression that examines program state is evaluated when the
786 tracepoint is reached, in order to determine whether to capture
787 trace data. If the condition is simple and false, processing the
788 tracepoint finishes very quickly and no data is gathered.
790 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
791 for static tracepoints support.
793 - GDBserver now supports x86_64 Windows 64-bit debugging.
795 * GDB now sends xmlRegisters= in qSupported packet to indicate that
796 it understands register description.
798 * The --batch flag now disables pagination and queries.
800 * X86 general purpose registers
802 GDB now supports reading/writing byte, word and double-word x86
803 general purpose registers directly. This means you can use, say,
804 $ah or $ax to refer, respectively, to the byte register AH and
805 16-bit word register AX that are actually portions of the 32-bit
806 register EAX or 64-bit register RAX.
808 * The `commands' command now accepts a range of breakpoints to modify.
809 A plain `commands' following a command that creates multiple
810 breakpoints affects all the breakpoints set by that command. This
811 applies to breakpoints set by `rbreak', and also applies when a
812 single `break' command creates multiple breakpoints (e.g.,
813 breakpoints on overloaded c++ functions).
815 * The `rbreak' command now accepts a filename specification as part of
816 its argument, limiting the functions selected by the regex to those
817 in the specified file.
819 * Support for remote debugging Windows and SymbianOS shared libraries
820 from Unix hosts has been improved. Non Windows GDB builds now can
821 understand target reported file names that follow MS-DOS based file
822 system semantics, such as file names that include drive letters and
823 use the backslash character as directory separator. This makes it
824 possible to transparently use the "set sysroot" and "set
825 solib-search-path" on Unix hosts to point as host copies of the
826 target's shared libraries. See the new command "set
827 target-file-system-kind" described below, and the "Commands to
828 specify files" section in the user manual for more information.
832 eval template, expressions...
833 Convert the values of one or more expressions under the control
834 of the string template to a command line, and call it.
836 set target-file-system-kind unix|dos-based|auto
837 show target-file-system-kind
838 Set or show the assumed file system kind for target reported file
841 save breakpoints <filename>
842 Save all current breakpoint definitions to a file suitable for use
843 in a later debugging session. To read the saved breakpoint
844 definitions, use the `source' command.
846 `save tracepoints' is a new alias for `save-tracepoints'. The latter
849 info static-tracepoint-markers
850 Display information about static tracepoint markers in the target.
852 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
853 Define a static tracepoint by probing a marker at the given
854 function, line, address, or marker ID.
858 Enable and disable observer mode.
860 set may-write-registers on|off
861 set may-write-memory on|off
862 set may-insert-breakpoints on|off
863 set may-insert-tracepoints on|off
864 set may-insert-fast-tracepoints on|off
865 set may-interrupt on|off
866 Set individual permissions for GDB effects on the target. Note that
867 some of these settings can have undesirable or surprising
868 consequences, particularly when changed in the middle of a session.
869 For instance, disabling the writing of memory can prevent
870 breakpoints from being inserted, cause single-stepping to fail, or
871 even crash your program, if you disable after breakpoints have been
872 inserted. However, GDB should not crash.
874 set record memory-query on|off
875 show record memory-query
876 Control whether to stop the inferior if memory changes caused
877 by an instruction cannot be recorded.
882 The disassemble command now supports "start,+length" form of two arguments.
886 ** GDB now provides a new directory location, called the python directory,
887 where Python scripts written for GDB can be installed. The location
888 of that directory is <data-directory>/python, where <data-directory>
889 is the GDB data directory. For more details, see section `Scripting
890 GDB using Python' in the manual.
892 ** The GDB Python API now has access to breakpoints, symbols, symbol
893 tables, program spaces, inferiors, threads and frame's code blocks.
894 Additionally, GDB Parameters can now be created from the API, and
895 manipulated via set/show in the CLI.
897 ** New functions gdb.target_charset, gdb.target_wide_charset,
898 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
900 ** New exception gdb.GdbError.
902 ** Pretty-printers are now also looked up in the current program space.
904 ** Pretty-printers can now be individually enabled and disabled.
906 ** GDB now looks for names of Python scripts to auto-load in a
907 special section named `.debug_gdb_scripts', in addition to looking
908 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
910 * Tracepoint actions were unified with breakpoint commands. In particular,
911 there are no longer differences in "info break" output for breakpoints and
912 tracepoints and the "commands" command can be used for both tracepoints and
917 ARM Symbian arm*-*-symbianelf*
919 * D language support.
920 GDB now supports debugging programs written in the D programming
923 * GDB now supports the extended ptrace interface for PowerPC which is
924 available since Linux kernel version 2.6.34. This automatically enables
925 any hardware breakpoints and additional hardware watchpoints available in
926 the processor. The old ptrace interface exposes just one hardware
927 watchpoint and no hardware breakpoints.
929 * GDB is now able to use the Data Value Compare (DVC) register available on
930 embedded PowerPC processors to implement in hardware simple watchpoint
931 conditions of the form:
933 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
935 This works in native GDB running on Linux kernels with the extended ptrace
936 interface mentioned above.
938 *** Changes in GDB 7.1
944 GDB now supports importing of namespaces in C++. This enables the
945 user to inspect variables from imported namespaces. Support for
946 namepace aliasing has also been added. So, if a namespace is
947 aliased in the current scope (e.g. namepace C=A; ) the user can
948 print variables using the alias (e.g. (gdb) print C::x).
952 All known bugs relating to the printing of virtual base class were
953 fixed. It is now possible to call overloaded static methods using a
958 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
959 and reinterpret_cast<> are now handled by the C++ expression parser.
963 Xilinx MicroBlaze microblaze-*-*
968 Xilinx MicroBlaze microblaze
971 * Multi-program debugging.
973 GDB now has support for multi-program (a.k.a. multi-executable or
974 multi-exec) debugging. This allows for debugging multiple inferiors
975 simultaneously each running a different program under the same GDB
976 session. See "Debugging Multiple Inferiors and Programs" in the
977 manual for more information. This implied some user visible changes
978 in the multi-inferior support. For example, "info inferiors" now
979 lists inferiors that are not running yet or that have exited
980 already. See also "New commands" and "New options" below.
982 * New tracing features
984 GDB's tracepoint facility now includes several new features:
986 ** Trace state variables
988 GDB tracepoints now include support for trace state variables, which
989 are variables managed by the target agent during a tracing
990 experiment. They are useful for tracepoints that trigger each
991 other, so for instance one tracepoint can count hits in a variable,
992 and then a second tracepoint has a condition that is true when the
993 count reaches a particular value. Trace state variables share the
994 $-syntax of GDB convenience variables, and can appear in both
995 tracepoint actions and condition expressions. Use the "tvariable"
996 command to create, and "info tvariables" to view; see "Trace State
997 Variables" in the manual for more detail.
1001 GDB now includes an option for defining fast tracepoints, which
1002 targets may implement more efficiently, such as by installing a jump
1003 into the target agent rather than a trap instruction. The resulting
1004 speedup can be by two orders of magnitude or more, although the
1005 tradeoff is that some program locations on some target architectures
1006 might not allow fast tracepoint installation, for instance if the
1007 instruction to be replaced is shorter than the jump. To request a
1008 fast tracepoint, use the "ftrace" command, with syntax identical to
1009 the regular trace command.
1011 ** Disconnected tracing
1013 It is now possible to detach GDB from the target while it is running
1014 a trace experiment, then reconnect later to see how the experiment
1015 is going. In addition, a new variable disconnected-tracing lets you
1016 tell the target agent whether to continue running a trace if the
1017 connection is lost unexpectedly.
1021 GDB now has the ability to save the trace buffer into a file, and
1022 then use that file as a target, similarly to you can do with
1023 corefiles. You can select trace frames, print data that was
1024 collected in them, and use tstatus to display the state of the
1025 tracing run at the moment that it was saved. To create a trace
1026 file, use "tsave <filename>", and to use it, do "target tfile
1029 ** Circular trace buffer
1031 You can ask the target agent to handle the trace buffer as a
1032 circular buffer, discarding the oldest trace frames to make room for
1033 newer ones, by setting circular-trace-buffer to on. This feature may
1034 not be available for all target agents.
1039 The disassemble command, when invoked with two arguments, now requires
1040 the arguments to be comma-separated.
1043 The info variables command now displays variable definitions. Files
1044 which only declare a variable are not shown.
1047 The source command is now capable of sourcing Python scripts.
1048 This feature is dependent on the debugger being build with Python
1051 Related to this enhancement is also the introduction of a new command
1052 "set script-extension" (see below).
1054 * New commands (for set/show, see "New options" below)
1056 record save [<FILENAME>]
1057 Save a file (in core file format) containing the process record
1058 execution log for replay debugging at a later time.
1060 record restore <FILENAME>
1061 Restore the process record execution log that was saved at an
1062 earlier time, for replay debugging.
1064 add-inferior [-copies <N>] [-exec <FILENAME>]
1067 clone-inferior [-copies <N>] [ID]
1068 Make a new inferior ready to execute the same program another
1069 inferior has loaded.
1074 maint info program-spaces
1075 List the program spaces loaded into GDB.
1077 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1078 show remote interrupt-sequence
1079 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1080 as the sequence to the remote target in order to interrupt the execution.
1081 Ctrl-C is a default. Some system prefers BREAK which is high level of
1082 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1083 Magic SysRq g. It is BREAK signal and character 'g'.
1085 set remote interrupt-on-connect [on | off]
1086 show remote interrupt-on-connect
1087 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1088 remote target when gdb connects to it. This is needed when you debug
1091 set remotebreak [on | off]
1093 Deprecated. Use "set/show remote interrupt-sequence" instead.
1095 tvariable $NAME [ = EXP ]
1096 Create or modify a trace state variable.
1099 List trace state variables and their values.
1101 delete tvariable $NAME ...
1102 Delete one or more trace state variables.
1105 Evaluate the given expressions without collecting anything into the
1106 trace buffer. (Valid in tracepoint actions only.)
1108 ftrace FN / FILE:LINE / *ADDR
1109 Define a fast tracepoint at the given function, line, or address.
1111 * New expression syntax
1113 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1114 GDB now parses 0b101010 identically with 42.
1118 set follow-exec-mode new|same
1119 show follow-exec-mode
1120 Control whether GDB reuses the same inferior across an exec call or
1121 creates a new one. This is useful to be able to restart the old
1122 executable after the inferior having done an exec call.
1124 set default-collect EXPR, ...
1125 show default-collect
1126 Define a list of expressions to be collected at each tracepoint.
1127 This is a useful way to ensure essential items are not overlooked,
1128 such as registers or a critical global variable.
1130 set disconnected-tracing
1131 show disconnected-tracing
1132 If set to 1, the target is instructed to continue tracing if it
1133 loses its connection to GDB. If 0, the target is to stop tracing
1136 set circular-trace-buffer
1137 show circular-trace-buffer
1138 If set to on, the target is instructed to use a circular trace buffer
1139 and discard the oldest trace frames instead of stopping the trace due
1140 to a full trace buffer. If set to off, the trace stops when the buffer
1141 fills up. Some targets may not support this.
1143 set script-extension off|soft|strict
1144 show script-extension
1145 If set to "off", the debugger does not perform any script language
1146 recognition, and all sourced files are assumed to be GDB scripts.
1147 If set to "soft" (the default), files are sourced according to
1148 filename extension, falling back to GDB scripts if the first
1150 If set to "strict", files are sourced according to filename extension.
1152 set ada trust-PAD-over-XVS on|off
1153 show ada trust-PAD-over-XVS
1154 If off, activate a workaround against a bug in the debugging information
1155 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1156 the GCC sources for more information about the GNAT encoding and
1157 PAD types in particular). It is always safe to set this option to
1158 off, but this introduces a slight performance penalty. The default
1161 * Python API Improvements
1163 ** GDB provides the new class gdb.LazyString. This is useful in
1164 some pretty-printing cases. The new method gdb.Value.lazy_string
1165 provides a simple way to create objects of this type.
1167 ** The fields returned by gdb.Type.fields now have an
1168 `is_base_class' attribute.
1170 ** The new method gdb.Type.range returns the range of an array type.
1172 ** The new method gdb.parse_and_eval can be used to parse and
1173 evaluate an expression.
1175 * New remote packets
1178 Define a trace state variable.
1181 Get the current value of a trace state variable.
1184 Set desired tracing behavior upon disconnection.
1187 Set the trace buffer to be linear or circular.
1190 Get data about the tracepoints currently in use.
1194 Process record now works correctly with hardware watchpoints.
1196 Multiple bug fixes have been made to the mips-irix port, making it
1197 much more reliable. In particular:
1198 - Debugging threaded applications is now possible again. Previously,
1199 GDB would hang while starting the program, or while waiting for
1200 the program to stop at a breakpoint.
1201 - Attaching to a running process no longer hangs.
1202 - An error occurring while loading a core file has been fixed.
1203 - Changing the value of the PC register now works again. This fixes
1204 problems observed when using the "jump" command, or when calling
1205 a function from GDB, or even when assigning a new value to $pc.
1206 - With the "finish" and "return" commands, the return value for functions
1207 returning a small array is now correctly printed.
1208 - It is now possible to break on shared library code which gets executed
1209 during a shared library init phase (code executed while executing
1210 their .init section). Previously, the breakpoint would have no effect.
1211 - GDB is now able to backtrace through the signal handler for
1212 non-threaded programs.
1214 PIE (Position Independent Executable) programs debugging is now supported.
1215 This includes debugging execution of PIC (Position Independent Code) shared
1216 libraries although for that, it should be possible to run such libraries as an
1219 *** Changes in GDB 7.0
1221 * GDB now has an interface for JIT compilation. Applications that
1222 dynamically generate code can create symbol files in memory and register
1223 them with GDB. For users, the feature should work transparently, and
1224 for JIT developers, the interface is documented in the GDB manual in the
1225 "JIT Compilation Interface" chapter.
1227 * Tracepoints may now be conditional. The syntax is as for
1228 breakpoints; either an "if" clause appended to the "trace" command,
1229 or the "condition" command is available. GDB sends the condition to
1230 the target for evaluation using the same bytecode format as is used
1231 for tracepoint actions.
1233 * The disassemble command now supports: an optional /r modifier, print the
1234 raw instructions in hex as well as in symbolic form, and an optional /m
1235 modifier to print mixed source+assembly.
1237 * Process record and replay
1239 In a architecture environment that supports ``process record and
1240 replay'', ``process record and replay'' target can record a log of
1241 the process execution, and replay it with both forward and reverse
1244 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1245 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1246 set execution-direction {forward|reverse}, for targets that support
1249 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1250 feature is available with a native GDB running on kernel version
1253 * GDB now has support for multi-byte and wide character sets on the
1254 target. Strings whose character type is wchar_t, char16_t, or
1255 char32_t are now correctly printed. GDB supports wide- and unicode-
1256 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1257 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1258 `printf'. This feature requires iconv to work properly; if your
1259 system does not have a working iconv, GDB can use GNU libiconv. See
1260 the installation instructions for more information.
1262 * GDB now supports automatic retrieval of shared library files from
1263 remote targets. To use this feature, specify a system root that begins
1264 with the `remote:' prefix, either via the `set sysroot' command or via
1265 the `--with-sysroot' configure-time option.
1267 * "info sharedlibrary" now takes an optional regex of libraries to show,
1268 and it now reports if a shared library has no debugging information.
1270 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1271 now complete on file names.
1273 * When completing in expressions, gdb will attempt to limit
1274 completions to allowable structure or union fields, where appropriate.
1275 For instance, consider:
1277 # struct example { int f1; double f2; };
1278 # struct example variable;
1281 If the user types TAB at the end of this command line, the available
1282 completions will be "f1" and "f2".
1284 * Inlined functions are now supported. They show up in backtraces, and
1285 the "step", "next", and "finish" commands handle them automatically.
1287 * GDB now supports the token-splicing (##) and stringification (#)
1288 operators when expanding macros. It also supports variable-arity
1291 * GDB now supports inspecting extra signal information, exported by
1292 the new $_siginfo convenience variable. The feature is currently
1293 implemented on linux ARM, i386 and amd64.
1295 * GDB can now display the VFP floating point registers and NEON vector
1296 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1297 can provide these registers (requires Linux 2.6.30 or later). Remote
1298 and simulator targets may also provide them.
1300 * New remote packets
1303 Search memory for a sequence of bytes.
1306 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1307 operation over reliable transport links. Use of this packet is
1308 controlled by the `set remote noack-packet' command.
1311 Kill the process with the specified process ID. Use this in preference
1312 to `k' when multiprocess protocol extensions are supported.
1315 Obtains additional operating system information
1319 Read or write additional signal information.
1321 * Removed remote protocol undocumented extension
1323 An undocumented extension to the remote protocol's `S' stop reply
1324 packet that permited the stub to pass a process id was removed.
1325 Remote servers should use the `T' stop reply packet instead.
1327 * GDB now supports multiple function calling conventions according to the
1328 DWARF-2 DW_AT_calling_convention function attribute.
1330 * The SH target utilizes the aforementioned change to distinguish between gcc
1331 and Renesas calling convention. It also adds the new CLI commands
1332 `set/show sh calling-convention'.
1334 * GDB can now read compressed debug sections, as produced by GNU gold
1335 with the --compress-debug-sections=zlib flag.
1337 * 64-bit core files are now supported on AIX.
1339 * Thread switching is now supported on Tru64.
1341 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1342 which will be allocated using malloc later in program execution.
1344 * The qXfer:libraries:read remote procotol packet now allows passing a
1345 list of section offsets.
1347 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1348 conditions handling signals delivered during attach or thread creation
1349 have also been fixed.
1351 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1352 From the user's standpoint, all unqualified instances of True and False
1353 are treated as the standard definitions, regardless of context.
1355 * GDB now parses C++ symbol and type names more flexibly. For
1358 template<typename T> class C { };
1361 GDB will now correctly handle all of:
1363 ptype C<char const *>
1364 ptype C<char const*>
1365 ptype C<const char *>
1366 ptype C<const char*>
1368 * New features in the GDB remote stub, gdbserver
1370 - The "--wrapper" command-line argument tells gdbserver to use a
1371 wrapper program to launch programs for debugging.
1373 - On PowerPC and S/390 targets, it is now possible to use a single
1374 gdbserver executable to debug both 32-bit and 64-bit programs.
1375 (This requires gdbserver itself to be built as a 64-bit executable.)
1377 - gdbserver uses the new noack protocol mode for TCP connections to
1378 reduce communications latency, if also supported and enabled in GDB.
1380 - Support for the sparc64-linux-gnu target is now included in
1383 - The amd64-linux build of gdbserver now supports debugging both
1384 32-bit and 64-bit programs.
1386 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1387 now support hardware watchpoints, and will use them automatically
1392 GDB now has support for scripting using Python. Whether this is
1393 available is determined at configure time.
1395 New GDB commands can now be written in Python.
1397 * Ada tasking support
1399 Ada tasks can now be inspected in GDB. The following commands have
1403 Print the list of Ada tasks.
1405 Print detailed information about task number N.
1407 Print the task number of the current task.
1409 Switch the context of debugging to task number N.
1411 * Support for user-defined prefixed commands. The "define" command can
1412 add new commands to existing prefixes, e.g. "target".
1414 * Multi-inferior, multi-process debugging.
1416 GDB now has generalized support for multi-inferior debugging. See
1417 "Debugging Multiple Inferiors" in the manual for more information.
1418 Although availability still depends on target support, the command
1419 set is more uniform now. The GNU/Linux specific multi-forks support
1420 has been migrated to this new framework. This implied some user
1421 visible changes; see "New commands" and also "Removed commands"
1424 * Target descriptions can now describe the target OS ABI. See the
1425 "Target Description Format" section in the user manual for more
1428 * Target descriptions can now describe "compatible" architectures
1429 to indicate that the target can execute applications for a different
1430 architecture in addition to those for the main target architecture.
1431 See the "Target Description Format" section in the user manual for
1434 * Multi-architecture debugging.
1436 GDB now includes general supports for debugging applications on
1437 hybrid systems that use more than one single processor architecture
1438 at the same time. Each such hybrid architecture still requires
1439 specific support to be added. The only hybrid architecture supported
1440 in this version of GDB is the Cell Broadband Engine.
1442 * GDB now supports integrated debugging of Cell/B.E. applications that
1443 use both the PPU and SPU architectures. To enable support for hybrid
1444 Cell/B.E. debugging, you need to configure GDB to support both the
1445 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1446 --enable-targets configure option.
1448 * Non-stop mode debugging.
1450 For some targets, GDB now supports an optional mode of operation in
1451 which you can examine stopped threads while other threads continue
1452 to execute freely. This is referred to as non-stop mode, with the
1453 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1454 section in the user manual for more information.
1456 To be able to support remote non-stop debugging, a remote stub needs
1457 to implement the non-stop mode remote protocol extensions, as
1458 described in the "Remote Non-Stop" section of the user manual. The
1459 GDB remote stub, gdbserver, has been adjusted to support these
1460 extensions on linux targets.
1462 * New commands (for set/show, see "New options" below)
1464 catch syscall [NAME(S) | NUMBER(S)]
1465 Catch system calls. Arguments, which should be names of system
1466 calls or their numbers, mean catch only those syscalls. Without
1467 arguments, every syscall will be caught. When the inferior issues
1468 any of the specified syscalls, GDB will stop and announce the system
1469 call, both when it is called and when its call returns. This
1470 feature is currently available with a native GDB running on the
1471 Linux Kernel, under the following architectures: x86, x86_64,
1472 PowerPC and PowerPC64.
1474 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1476 Search memory for a sequence of bytes.
1478 maint set python print-stack
1479 maint show python print-stack
1480 Show a stack trace when an error is encountered in a Python script.
1483 Invoke CODE by passing it to the Python interpreter.
1488 These allow macros to be defined, undefined, and listed
1492 Show operating system information about processes.
1495 List the inferiors currently under GDB's control.
1498 Switch focus to inferior number NUM.
1501 Detach from inferior number NUM.
1504 Kill inferior number NUM.
1508 set spu stop-on-load
1509 show spu stop-on-load
1510 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1512 set spu auto-flush-cache
1513 show spu auto-flush-cache
1514 Control whether to automatically flush the software-managed cache
1515 during Cell/B.E. debugging.
1517 set sh calling-convention
1518 show sh calling-convention
1519 Control the calling convention used when calling SH target functions.
1522 show debug timestamp
1523 Control display of timestamps with GDB debugging output.
1525 set disassemble-next-line
1526 show disassemble-next-line
1527 Control display of disassembled source lines or instructions when
1530 set remote noack-packet
1531 show remote noack-packet
1532 Set/show the use of remote protocol QStartNoAckMode packet. See above
1533 under "New remote packets."
1535 set remote query-attached-packet
1536 show remote query-attached-packet
1537 Control use of remote protocol `qAttached' (query-attached) packet.
1539 set remote read-siginfo-object
1540 show remote read-siginfo-object
1541 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1544 set remote write-siginfo-object
1545 show remote write-siginfo-object
1546 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1549 set remote reverse-continue
1550 show remote reverse-continue
1551 Control use of remote protocol 'bc' (reverse-continue) packet.
1553 set remote reverse-step
1554 show remote reverse-step
1555 Control use of remote protocol 'bs' (reverse-step) packet.
1557 set displaced-stepping
1558 show displaced-stepping
1559 Control displaced stepping mode. Displaced stepping is a way to
1560 single-step over breakpoints without removing them from the debuggee.
1561 Also known as "out-of-line single-stepping".
1564 show debug displaced
1565 Control display of debugging info for displaced stepping.
1567 maint set internal-error
1568 maint show internal-error
1569 Control what GDB does when an internal error is detected.
1571 maint set internal-warning
1572 maint show internal-warning
1573 Control what GDB does when an internal warning is detected.
1578 Use a wrapper program to launch programs for debugging.
1580 set multiple-symbols (all|ask|cancel)
1581 show multiple-symbols
1582 The value of this variable can be changed to adjust the debugger behavior
1583 when an expression or a breakpoint location contains an ambiguous symbol
1584 name (an overloaded function name, for instance).
1586 set breakpoint always-inserted
1587 show breakpoint always-inserted
1588 Keep breakpoints always inserted in the target, as opposed to inserting
1589 them when resuming the target, and removing them when the target stops.
1590 This option can improve debugger performance on slow remote targets.
1592 set arm fallback-mode (arm|thumb|auto)
1593 show arm fallback-mode
1594 set arm force-mode (arm|thumb|auto)
1596 These commands control how ARM GDB determines whether instructions
1597 are ARM or Thumb. The default for both settings is auto, which uses
1598 the current CPSR value for instructions without symbols; previous
1599 versions of GDB behaved as if "set arm fallback-mode arm".
1601 set disable-randomization
1602 show disable-randomization
1603 Standalone programs run with the virtual address space randomization enabled
1604 by default on some platforms. This option keeps the addresses stable across
1605 multiple debugging sessions.
1609 Control whether other threads are stopped or not when some thread hits
1614 Requests that asynchronous execution is enabled in the target, if available.
1615 In this case, it's possible to resume target in the background, and interact
1616 with GDB while the target is running. "show target-async" displays the
1617 current state of asynchronous execution of the target.
1619 set target-wide-charset
1620 show target-wide-charset
1621 The target-wide-charset is the name of the character set that GDB
1622 uses when printing characters whose type is wchar_t.
1624 set tcp auto-retry (on|off)
1626 set tcp connect-timeout
1627 show tcp connect-timeout
1628 These commands allow GDB to retry failed TCP connections to a remote stub
1629 with a specified timeout period; this is useful if the stub is launched
1630 in parallel with GDB but may not be ready to accept connections immediately.
1632 set libthread-db-search-path
1633 show libthread-db-search-path
1634 Control list of directories which GDB will search for appropriate
1637 set schedule-multiple (on|off)
1638 show schedule-multiple
1639 Allow GDB to resume all threads of all processes or only threads of
1640 the current process.
1644 Use more aggressive caching for accesses to the stack. This improves
1645 performance of remote debugging (particularly backtraces) without
1646 affecting correctness.
1648 set interactive-mode (on|off|auto)
1649 show interactive-mode
1650 Control whether GDB runs in interactive mode (on) or not (off).
1651 When in interactive mode, GDB waits for the user to answer all
1652 queries. Otherwise, GDB does not wait and assumes the default
1653 answer. When set to auto (the default), GDB determines which
1654 mode to use based on the stdin settings.
1659 For program forks, this is replaced by the new more generic `info
1660 inferiors' command. To list checkpoints, you can still use the
1661 `info checkpoints' command, which was an alias for the `info forks'
1665 Replaced by the new `inferior' command. To switch between
1666 checkpoints, you can still use the `restart' command, which was an
1667 alias for the `fork' command.
1670 This is removed, since some targets don't have a notion of
1671 processes. To switch between processes, you can still use the
1672 `inferior' command using GDB's own inferior number.
1675 For program forks, this is replaced by the new more generic `kill
1676 inferior' command. To delete a checkpoint, you can still use the
1677 `delete checkpoint' command, which was an alias for the `delete
1681 For program forks, this is replaced by the new more generic `detach
1682 inferior' command. To detach a checkpoint, you can still use the
1683 `detach checkpoint' command, which was an alias for the `detach
1686 * New native configurations
1688 x86/x86_64 Darwin i[34567]86-*-darwin*
1690 x86_64 MinGW x86_64-*-mingw*
1694 Lattice Mico32 lm32-*
1695 x86 DICOS i[34567]86-*-dicos*
1696 x86_64 DICOS x86_64-*-dicos*
1699 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1700 (mingw32ce) debugging.
1706 These commands were actually not implemented on any target.
1708 *** Changes in GDB 6.8
1710 * New native configurations
1712 NetBSD/hppa hppa*-*netbsd*
1713 Xtensa GNU/Linux xtensa*-*-linux*
1717 NetBSD/hppa hppa*-*-netbsd*
1718 Xtensa GNU/Lunux xtensa*-*-linux*
1720 * Change in command line behavior -- corefiles vs. process ids.
1722 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1723 attaching to process NUMBER fails, GDB no longer attempts to open a
1724 core file named NUMBER. Attaching to a program using the -c option
1725 is no longer supported. Instead, use the '-p' or '--pid' options.
1727 * GDB can now be built as a native debugger for debugging Windows x86
1728 (mingw32) Portable Executable (PE) programs.
1730 * Pending breakpoints no longer change their number when their address
1733 * GDB now supports breakpoints with multiple locations,
1734 including breakpoints on C++ constructors, inside C++ templates,
1735 and in inlined functions.
1737 * GDB's ability to debug optimized code has been improved. GDB more
1738 accurately identifies function bodies and lexical blocks that occupy
1739 more than one contiguous range of addresses.
1741 * Target descriptions can now describe registers for PowerPC.
1743 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1744 registers on PowerPC targets.
1746 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1747 targets even when the libthread_db library is not available.
1749 * The GDB remote stub, gdbserver, now supports the new file transfer
1750 commands (remote put, remote get, and remote delete).
1752 * The GDB remote stub, gdbserver, now supports run and attach in
1753 extended-remote mode.
1755 * hppa*64*-*-hpux11* target broken
1756 The debugger is unable to start a program and fails with the following
1757 error: "Error trying to get information about dynamic linker".
1758 The gdb-6.7 release is also affected.
1760 * GDB now supports the --enable-targets= configure option to allow
1761 building a single GDB executable that supports multiple remote
1762 target architectures.
1764 * GDB now supports debugging C and C++ programs which use the
1765 Decimal Floating Point extension. In addition, the PowerPC target
1766 now has a set of pseudo-registers to inspect decimal float values
1767 stored in two consecutive float registers.
1769 * The -break-insert MI command can optionally create pending
1772 * Improved support for debugging Ada
1773 Many improvements to the Ada language support have been made. These
1775 - Better support for Ada2005 interface types
1776 - Improved handling of arrays and slices in general
1777 - Better support for Taft-amendment types
1778 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1780 - Improved command completion in Ada
1783 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1788 set print frame-arguments (all|scalars|none)
1789 show print frame-arguments
1790 The value of this variable can be changed to control which argument
1791 values should be printed by the debugger when displaying a frame.
1796 Transfer files to and from a remote target, and delete remote files.
1803 Transfer files to and from a remote target, and delete remote files.
1805 * New remote packets
1812 Open, close, read, write, and delete files on the remote system.
1815 Attach to an existing process on the remote system, in extended-remote
1819 Run a new process on the remote system, in extended-remote mode.
1821 *** Changes in GDB 6.7
1823 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1824 bfd, libiberty and opcodes, as revealed by static analysis donated by
1825 Coverity, Inc. (http://scan.coverity.com).
1827 * When looking up multiply-defined global symbols, GDB will now prefer the
1828 symbol definition in the current shared library if it was built using the
1829 -Bsymbolic linker option.
1831 * When the Text User Interface (TUI) is not configured, GDB will now
1832 recognize the -tui command-line option and print a message that the TUI
1835 * The GDB remote stub, gdbserver, now has lower overhead for high
1836 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1838 * GDB for MIPS targets now autodetects whether a remote target provides
1839 32-bit or 64-bit register values.
1841 * Support for C++ member pointers has been improved.
1843 * GDB now understands XML target descriptions, which specify the
1844 target's overall architecture. GDB can read a description from
1845 a local file or over the remote serial protocol.
1847 * Vectors of single-byte data use a new integer type which is not
1848 automatically displayed as character or string data.
1850 * The /s format now works with the print command. It displays
1851 arrays of single-byte integers and pointers to single-byte integers
1854 * Target descriptions can now describe target-specific registers,
1855 for architectures which have implemented the support (currently
1856 only ARM, M68K, and MIPS).
1858 * GDB and the GDB remote stub, gdbserver, now support the XScale
1861 * The GDB remote stub, gdbserver, has been updated to support
1862 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1863 has been rewritten to use the standard GDB remote protocol.
1865 * GDB can now step into C++ functions which are called through thunks.
1867 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1869 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1870 layout. It also supports a TextSeg= and DataSeg= response when only
1871 segment base addresses (rather than offsets) are available.
1873 * The /i format now outputs any trailing branch delay slot instructions
1874 immediately following the last instruction within the count specified.
1876 * The GDB remote protocol "T" stop reply packet now supports a
1877 "library" response. Combined with the new "qXfer:libraries:read"
1878 packet, this response allows GDB to debug shared libraries on targets
1879 where the operating system manages the list of loaded libraries (e.g.
1880 Windows and SymbianOS).
1882 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1883 (DLLs) on Windows and Windows CE targets.
1885 * GDB now supports a faster verification that a .debug file matches its binary
1886 according to its build-id signature, if the signature is present.
1892 Enable or disable hardware flow control (RTS/CTS) on the serial port
1893 when debugging using remote targets.
1895 set mem inaccessible-by-default
1896 show mem inaccessible-by-default
1897 If the target supplies a memory map, for instance via the remote
1898 protocol's "qXfer:memory-map:read" packet, setting this variable
1899 prevents GDB from accessing memory outside the memory map. This
1900 is useful for targets with memory mapped registers or which react
1901 badly to accesses of unmapped address space.
1903 set breakpoint auto-hw
1904 show breakpoint auto-hw
1905 If the target supplies a memory map, for instance via the remote
1906 protocol's "qXfer:memory-map:read" packet, setting this variable
1907 lets GDB use hardware breakpoints automatically for memory regions
1908 where it can not use software breakpoints. This covers both the
1909 "break" command and internal breakpoints used for other commands
1910 including "next" and "finish".
1913 catch exception unhandled
1914 Stop the program execution when Ada exceptions are raised.
1917 Stop the program execution when an Ada assertion failed.
1921 Set an alternate system root for target files. This is a more
1922 general version of "set solib-absolute-prefix", which is now
1923 an alias to "set sysroot".
1926 Provide extended SPU facility status information. This set of
1927 commands is available only when debugging the Cell/B.E. SPU
1930 * New native configurations
1932 OpenBSD/sh sh*-*openbsd*
1935 unset tdesc filename
1937 Use the specified local file as an XML target description, and do
1938 not query the target for its built-in description.
1942 OpenBSD/sh sh*-*-openbsd*
1943 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1944 Toshiba Media Processor mep-elf
1946 * New remote packets
1949 Ignore the specified signals; pass them directly to the debugged program
1950 without stopping other threads or reporting them to GDB.
1952 qXfer:features:read:
1953 Read an XML target description from the target, which describes its
1958 Read or write contents of an spufs file on the target system. These
1959 packets are available only on the Cell/B.E. SPU architecture.
1961 qXfer:libraries:read:
1962 Report the loaded shared libraries. Combined with new "T" packet
1963 response, this packet allows GDB to debug shared libraries on
1964 targets where the operating system manages the list of loaded
1965 libraries (e.g. Windows and SymbianOS).
1969 Support for these obsolete configurations has been removed.
1977 i[34567]86-*-lynxos*
1978 i[34567]86-*-netware*
1979 i[34567]86-*-sco3.2v5*
1980 i[34567]86-*-sco3.2v4*
1982 i[34567]86-*-sysv4.2*
1985 i[34567]86-*-unixware2*
1986 i[34567]86-*-unixware*
1995 * Other removed features
2002 Various m68k-only ROM monitors.
2009 Various Renesas ROM monitors and debugging interfaces for SH and
2014 Support for a Macraigor serial interface to on-chip debugging.
2015 GDB does not directly support the newer parallel or USB
2020 A debug information format. The predecessor to DWARF 2 and
2021 DWARF 3, which are still supported.
2023 Support for the HP aCC compiler on HP-UX/PA-RISC
2025 SOM-encapsulated symbolic debugging information, automatic
2026 invocation of pxdb, and the aCC custom C++ ABI. This does not
2027 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2028 with aCC can still be debugged on an assembly level.
2030 MIPS ".pdr" sections
2032 A MIPS-specific format used to describe stack frame layout
2033 in debugging information.
2037 GDB could work with an older version of Guile to debug
2038 the interpreter and Scheme programs running in it.
2040 set mips stack-arg-size
2041 set mips saved-gpreg-size
2043 Use "set mips abi" to control parameter passing for MIPS.
2045 *** Changes in GDB 6.6
2050 Cell Broadband Engine SPU spu-elf
2052 * GDB can now be configured as a cross-debugger targeting native Windows
2053 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2054 running on a Windows system over TCP/IP to debug Windows programs.
2056 * The GDB remote stub, gdbserver, has been updated to support Windows and
2057 Cygwin debugging. Both single-threaded and multi-threaded programs are
2060 * The "set trust-readonly-sections" command works again. This command was
2061 broken in GDB 6.3, 6.4, and 6.5.
2063 * The "load" command now supports writing to flash memory, if the remote
2064 stub provides the required support.
2066 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2067 longer requires symbolic debug information (e.g. DWARF-2).
2072 unset substitute-path
2073 show substitute-path
2074 Manage a list of substitution rules that GDB uses to rewrite the name
2075 of the directories where the sources are located. This can be useful
2076 for instance when the sources were moved to a different location
2077 between compilation and debugging.
2081 Print each CLI command as it is executed. Each command is prefixed with
2082 a number of `+' symbols representing the nesting depth.
2083 The source command now has a `-v' option to enable the same feature.
2087 The ARM Demon monitor support (RDP protocol, "target rdp").
2089 Kernel Object Display, an embedded debugging feature which only worked with
2090 an obsolete version of Cisco IOS.
2092 The 'set download-write-size' and 'show download-write-size' commands.
2094 * New remote packets
2097 Tell a stub about GDB client features, and request remote target features.
2098 The first feature implemented is PacketSize, which allows the target to
2099 specify the size of packets it can handle - to minimize the number of
2100 packets required and improve performance when connected to a remote
2104 Fetch an OS auxilliary vector from the remote stub. This packet is a
2105 more efficient replacement for qPart:auxv:read.
2107 qXfer:memory-map:read:
2108 Fetch a memory map from the remote stub, including information about
2109 RAM, ROM, and flash memory devices.
2114 Erase and program a flash memory device.
2116 * Removed remote packets
2119 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2120 used it, and only gdbserver implemented it.
2122 *** Changes in GDB 6.5
2126 Renesas M32C/M16C m32c-elf
2128 Morpho Technologies ms1 ms1-elf
2132 init-if-undefined Initialize a convenience variable, but
2133 only if it doesn't already have a value.
2135 The following commands are presently only implemented for native GNU/Linux:
2137 checkpoint Save a snapshot of the program state.
2139 restart <n> Return the program state to a
2140 previously saved state.
2142 info checkpoints List currently saved checkpoints.
2144 delete-checkpoint <n> Delete a previously saved checkpoint.
2146 set|show detach-on-fork Tell gdb whether to detach from a newly
2147 forked process, or to keep debugging it.
2149 info forks List forks of the user program that
2150 are available to be debugged.
2152 fork <n> Switch to debugging one of several
2153 forks of the user program that are
2154 available to be debugged.
2156 delete-fork <n> Delete a fork from the list of forks
2157 that are available to be debugged (and
2158 kill the forked process).
2160 detach-fork <n> Delete a fork from the list of forks
2161 that are available to be debugged (and
2162 allow the process to continue).
2166 Morpho Technologies ms2 ms1-elf
2168 * Improved Windows host support
2170 GDB now builds as a cross debugger hosted on i686-mingw32, including
2171 native console support, and remote communications using either
2172 network sockets or serial ports.
2174 * Improved Modula-2 language support
2176 GDB can now print most types in the Modula-2 syntax. This includes:
2177 basic types, set types, record types, enumerated types, range types,
2178 pointer types and ARRAY types. Procedure var parameters are correctly
2179 printed and hexadecimal addresses and character constants are also
2180 written in the Modula-2 syntax. Best results can be obtained by using
2181 GNU Modula-2 together with the -gdwarf-2 command line option.
2185 The ARM rdi-share module.
2187 The Netware NLM debug server.
2189 *** Changes in GDB 6.4
2191 * New native configurations
2193 OpenBSD/arm arm*-*-openbsd*
2194 OpenBSD/mips64 mips64-*-openbsd*
2198 Morpho Technologies ms1 ms1-elf
2200 * New command line options
2202 --batch-silent As for --batch, but totally silent.
2203 --return-child-result The debugger will exist with the same value
2204 the child (debugged) program exited with.
2205 --eval-command COMMAND, -ex COMMAND
2206 Execute a single GDB CLI command. This may be
2207 specified multiple times and in conjunction
2208 with the --command (-x) option.
2210 * Deprecated commands removed
2212 The following commands, that were deprecated in 2000, have been
2216 set|show arm disassembly-flavor set|show arm disassembler
2217 othernames set arm disassembler
2218 set|show remotedebug set|show debug remote
2219 set|show archdebug set|show debug arch
2220 set|show eventdebug set|show debug event
2223 * New BSD user-level threads support
2225 It is now possible to debug programs using the user-level threads
2226 library on OpenBSD and FreeBSD. Currently supported (target)
2229 FreeBSD/amd64 x86_64-*-freebsd*
2230 FreeBSD/i386 i386-*-freebsd*
2231 OpenBSD/i386 i386-*-openbsd*
2233 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2234 are not yet supported.
2236 * New support for Matsushita MN10300 w/sim added
2237 (Work in progress). mn10300-elf.
2239 * REMOVED configurations and files
2241 VxWorks and the XDR protocol *-*-vxworks
2242 Motorola MCORE mcore-*-*
2243 National Semiconductor NS32000 ns32k-*-*
2245 * New "set print array-indexes" command
2247 After turning this setting "on", GDB prints the index of each element
2248 when displaying arrays. The default is "off" to preserve the previous
2251 * VAX floating point support
2253 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2255 * User-defined command support
2257 In addition to using $arg0..$arg9 for argument passing, it is now possible
2258 to use $argc to determine now many arguments have been passed. See the
2259 section on user-defined commands in the user manual for more information.
2261 *** Changes in GDB 6.3:
2263 * New command line option
2265 GDB now accepts -l followed by a number to set the timeout for remote
2268 * GDB works with GCC -feliminate-dwarf2-dups
2270 GDB now supports a more compact representation of DWARF-2 debug
2271 information using DW_FORM_ref_addr references. These are produced
2272 by GCC with the option -feliminate-dwarf2-dups and also by some
2273 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2274 to use -feliminate-dwarf2-dups.
2276 * Internationalization
2278 When supported by the host system, GDB will be built with
2279 internationalization (libintl). The task of marking up the sources is
2280 continued, we're looking forward to our first translation.
2284 Initial support for debugging programs compiled with the GNAT
2285 implementation of the Ada programming language has been integrated
2286 into GDB. In this release, support is limited to expression evaluation.
2288 * New native configurations
2290 GNU/Linux/m32r m32r-*-linux-gnu
2294 GDB's remote protocol now includes support for the 'p' packet. This
2295 packet is used to fetch individual registers from a remote inferior.
2297 * END-OF-LIFE registers[] compatibility module
2299 GDB's internal register infrastructure has been completely rewritten.
2300 The new infrastructure making possible the implementation of key new
2301 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2304 GDB 6.3 will be the last release to include the the registers[]
2305 compatibility module that allowed out-of-date configurations to
2306 continue to work. This change directly impacts the following
2316 powerpc bdm protocol
2318 Unless there is activity to revive these configurations, they will be
2319 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2321 * OBSOLETE configurations and files
2323 Configurations that have been declared obsolete in this release have
2324 been commented out. Unless there is activity to revive these
2325 configurations, the next release of GDB will have their sources
2326 permanently REMOVED.
2335 *** Changes in GDB 6.2.1:
2337 * MIPS `break main; run' gave an heuristic-fence-post warning
2339 When attempting to run even a simple program, a warning about
2340 heuristic-fence-post being hit would be reported. This problem has
2343 * MIPS IRIX 'long double' crashed GDB
2345 When examining a long double variable, GDB would get a segmentation
2346 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2347 IRIX long double values).
2351 A bug in the VAX stack code was causing problems with the "next"
2352 command. This problem has been fixed.
2354 *** Changes in GDB 6.2:
2356 * Fix for ``many threads''
2358 On GNU/Linux systems that use the NPTL threads library, a program
2359 rapidly creating and deleting threads would confuse GDB leading to the
2362 ptrace: No such process.
2363 thread_db_get_info: cannot get thread info: generic error
2365 This problem has been fixed.
2367 * "-async" and "-noasync" options removed.
2369 Support for the broken "-noasync" option has been removed (it caused
2372 * New ``start'' command.
2374 This command runs the program until the begining of the main procedure.
2376 * New BSD Kernel Data Access Library (libkvm) interface
2378 Using ``target kvm'' it is now possible to debug kernel core dumps and
2379 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2380 platforms. Currently supported (native-only) configurations are:
2382 FreeBSD/amd64 x86_64-*-freebsd*
2383 FreeBSD/i386 i?86-*-freebsd*
2384 NetBSD/i386 i?86-*-netbsd*
2385 NetBSD/m68k m68*-*-netbsd*
2386 NetBSD/sparc sparc-*-netbsd*
2387 OpenBSD/amd64 x86_64-*-openbsd*
2388 OpenBSD/i386 i?86-*-openbsd*
2389 OpenBSD/m68k m68*-openbsd*
2390 OpenBSD/sparc sparc-*-openbsd*
2392 * Signal trampoline code overhauled
2394 Many generic problems with GDB's signal handling code have been fixed.
2395 These include: backtraces through non-contiguous stacks; recognition
2396 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2397 call; backtrace through a signal trampoline; step into and out of
2398 signal handlers; and single-stepping in the signal trampoline.
2400 Please note that kernel bugs are a limiting factor here. These
2401 features have been shown to work on an s390 GNU/Linux system that
2402 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2404 * Cygwin support for DWARF 2 added.
2406 * New native configurations
2408 GNU/Linux/hppa hppa*-*-linux*
2409 OpenBSD/hppa hppa*-*-openbsd*
2410 OpenBSD/m68k m68*-*-openbsd*
2411 OpenBSD/m88k m88*-*-openbsd*
2412 OpenBSD/powerpc powerpc-*-openbsd*
2413 NetBSD/vax vax-*-netbsd*
2414 OpenBSD/vax vax-*-openbsd*
2416 * END-OF-LIFE frame compatibility module
2418 GDB's internal frame infrastructure has been completely rewritten.
2419 The new infrastructure making it possible to support key new features
2420 including DWARF 2 Call Frame Information. To aid in the task of
2421 migrating old configurations to this new infrastructure, a
2422 compatibility module, that allowed old configurations to continue to
2423 work, was also included.
2425 GDB 6.2 will be the last release to include this frame compatibility
2426 module. This change directly impacts the following configurations:
2436 Unless there is activity to revive these configurations, they will be
2437 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2439 * REMOVED configurations and files
2441 Sun 3, running SunOS 3 m68*-*-sunos3*
2442 Sun 3, running SunOS 4 m68*-*-sunos4*
2443 Sun 2, running SunOS 3 m68000-*-sunos3*
2444 Sun 2, running SunOS 4 m68000-*-sunos4*
2445 Motorola 680x0 running LynxOS m68*-*-lynxos*
2446 AT&T 3b1/Unix pc m68*-att-*
2447 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2448 decstation mips-dec-* mips-little-*
2449 riscos mips-*-riscos* mips-*-sysv*
2450 sonymips mips-sony-*
2451 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2453 *** Changes in GDB 6.1.1:
2455 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2457 The TUI (Text-mode User Interface) is now built as part of a default
2458 GDB configuration. It is enabled by either selecting the TUI with the
2459 command line option "-i=tui" or by running the separate "gdbtui"
2460 program. For more information on the TUI, see the manual "Debugging
2463 * Pending breakpoint support (also included in GDB 6.1)
2465 Support has been added to allow you to specify breakpoints in shared
2466 libraries that have not yet been loaded. If a breakpoint location
2467 cannot be found, and the "breakpoint pending" option is set to auto,
2468 GDB queries you if you wish to make the breakpoint pending on a future
2469 shared-library load. If and when GDB resolves the breakpoint symbol,
2470 the pending breakpoint is removed as one or more regular breakpoints
2473 Pending breakpoints are very useful for GCJ Java debugging.
2475 * Fixed ISO-C build problems
2477 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2478 non ISO-C code that stopped them being built using a more strict ISO-C
2479 compiler (e.g., IBM's C compiler).
2481 * Fixed build problem on IRIX 5
2483 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2484 wasn't able to compile compile on an IRIX 5 system.
2486 * Added execute permission to gdb/gdbserver/configure
2488 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2489 permission. This bug would cause configure to fail on a number of
2490 systems (Solaris, IRIX). Ref: server/519.
2492 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2494 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2495 has been updated to use constant array sizes.
2497 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2499 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2500 its generated DWARF Call Frame Info. This encoding was causing GDB to
2501 panic, that panic has been fixed. Ref: gdb/1628.
2503 * Fixed a problem when examining parameters in shared library code.
2505 When examining parameters in optimized shared library code generated
2506 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2507 not available''. GDB now correctly displays the variable's value.
2509 *** Changes in GDB 6.1:
2511 * Removed --with-mmalloc
2513 Support for the mmalloc memory manager has been removed, as it
2514 conflicted with the internal gdb byte cache.
2516 * Changes in AMD64 configurations
2518 The AMD64 target now includes the %cs and %ss registers. As a result
2519 the AMD64 remote protocol has changed; this affects the floating-point
2520 and SSE registers. If you rely on those registers for your debugging,
2521 you should upgrade gdbserver on the remote side.
2523 * Revised SPARC target
2525 The SPARC target has been completely revised, incorporating the
2526 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2527 support for LynxOS and SunOS 4 has been dropped. Calling functions
2528 from within GDB on operating systems with a non-executable stack
2529 (Solaris, OpenBSD) now works.
2533 GDB has a new C++ demangler which does a better job on the mangled
2534 names generated by current versions of g++. It also runs faster, so
2535 with this and other changes gdb should now start faster on large C++
2538 * DWARF 2 Location Expressions
2540 GDB support for location expressions has been extended to support function
2541 arguments and frame bases. Older versions of GDB could crash when they
2544 * C++ nested types and namespaces
2546 GDB's support for nested types and namespaces in C++ has been
2547 improved, especially if you use the DWARF 2 debugging format. (This
2548 is the default for recent versions of GCC on most platforms.)
2549 Specifically, if you have a class "Inner" defined within a class or
2550 namespace "Outer", then GDB realizes that the class's name is
2551 "Outer::Inner", not simply "Inner". This should greatly reduce the
2552 frequency of complaints about not finding RTTI symbols. In addition,
2553 if you are stopped at inside of a function defined within a namespace,
2554 GDB modifies its name lookup accordingly.
2556 * New native configurations
2558 NetBSD/amd64 x86_64-*-netbsd*
2559 OpenBSD/amd64 x86_64-*-openbsd*
2560 OpenBSD/alpha alpha*-*-openbsd*
2561 OpenBSD/sparc sparc-*-openbsd*
2562 OpenBSD/sparc64 sparc64-*-openbsd*
2564 * New debugging protocols
2566 M32R with SDI protocol m32r-*-elf*
2568 * "set prompt-escape-char" command deleted.
2570 The command "set prompt-escape-char" has been deleted. This command,
2571 and its very obscure effet on GDB's prompt, was never documented,
2572 tested, nor mentioned in the NEWS file.
2574 * OBSOLETE configurations and files
2576 Configurations that have been declared obsolete in this release have
2577 been commented out. Unless there is activity to revive these
2578 configurations, the next release of GDB will have their sources
2579 permanently REMOVED.
2581 Sun 3, running SunOS 3 m68*-*-sunos3*
2582 Sun 3, running SunOS 4 m68*-*-sunos4*
2583 Sun 2, running SunOS 3 m68000-*-sunos3*
2584 Sun 2, running SunOS 4 m68000-*-sunos4*
2585 Motorola 680x0 running LynxOS m68*-*-lynxos*
2586 AT&T 3b1/Unix pc m68*-att-*
2587 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2588 decstation mips-dec-* mips-little-*
2589 riscos mips-*-riscos* mips-*-sysv*
2590 sonymips mips-sony-*
2591 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2593 * REMOVED configurations and files
2595 SGI Irix-4.x mips-sgi-irix4 or iris4
2596 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2597 Z8000 simulator z8k-zilog-none or z8ksim
2598 Matsushita MN10200 w/simulator mn10200-*-*
2599 H8/500 simulator h8500-hitachi-hms or h8500hms
2600 HP/PA running BSD hppa*-*-bsd*
2601 HP/PA running OSF/1 hppa*-*-osf*
2602 HP/PA Pro target hppa*-*-pro*
2603 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2604 386BSD i[3456]86-*-bsd*
2605 Sequent family i[3456]86-sequent-sysv4*
2606 i[3456]86-sequent-sysv*
2607 i[3456]86-sequent-bsd*
2608 SPARC running LynxOS sparc-*-lynxos*
2609 SPARC running SunOS 4 sparc-*-sunos4*
2610 Tsqware Sparclet sparclet-*-*
2611 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2613 *** Changes in GDB 6.0:
2617 Support for debugging the Objective-C programming language has been
2618 integrated into GDB.
2620 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2622 DWARF 2's Call Frame Information makes available compiler generated
2623 information that more exactly describes the program's run-time stack.
2624 By using this information, GDB is able to provide more robust stack
2627 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2628 have been updated to use a new backtrace mechanism which includes
2629 DWARF 2 CFI support.
2633 GDB's remote protocol has been extended to include support for hosted
2634 file I/O (where the remote target uses GDB's file system). See GDB's
2635 remote protocol documentation for details.
2637 * All targets using the new architecture framework.
2639 All of GDB's targets have been updated to use the new internal
2640 architecture framework. The way is now open for future GDB releases
2641 to include cross-architecture native debugging support (i386 on amd64,
2644 * GNU/Linux's Thread Local Storage (TLS)
2646 GDB now includes support for for the GNU/Linux implementation of
2647 per-thread variables.
2649 * GNU/Linux's Native POSIX Thread Library (NPTL)
2651 GDB's thread code has been updated to work with either the new
2652 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2654 * Separate debug info.
2656 GDB, in conjunction with BINUTILS, now supports a mechanism for
2657 automatically loading debug information from a separate file. Instead
2658 of shipping full debug and non-debug versions of system libraries,
2659 system integrators can now instead ship just the stripped libraries
2660 and optional debug files.
2662 * DWARF 2 Location Expressions
2664 DWARF 2 Location Expressions allow the compiler to more completely
2665 describe the location of variables (even in optimized code) to the
2668 GDB now includes preliminary support for location expressions (support
2669 for DW_OP_piece is still missing).
2673 A number of long standing bugs that caused GDB to die while starting a
2674 Java application have been fixed. GDB's Java support is now
2675 considered "useable".
2677 * GNU/Linux support for fork, vfork, and exec.
2679 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2680 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2683 * GDB supports logging output to a file
2685 There are two new commands, "set logging" and "show logging", which can be
2686 used to capture GDB's output to a file.
2688 * The meaning of "detach" has changed for gdbserver
2690 The "detach" command will now resume the application, as documented. To
2691 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2694 * d10v, m68hc11 `regs' command deprecated
2696 The `info registers' command has been updated so that it displays the
2697 registers using a format identical to the old `regs' command.
2701 A new command, "maint set profile on/off", has been added. This command can
2702 be used to enable or disable profiling while running GDB, to profile a
2703 session or a set of commands. In addition there is a new configure switch,
2704 "--enable-profiling", which will cause GDB to be compiled with profiling
2705 data, for more informative profiling results.
2707 * Default MI syntax changed to "mi2".
2709 The default MI (machine interface) syntax, enabled by the command line
2710 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2711 "mi1", can be enabled by specifying the option "-i=mi1".
2713 Support for the original "mi0" syntax (included in GDB 5.0) has been
2716 Fix for gdb/192: removed extraneous space when displaying frame level.
2717 Fix for gdb/672: update changelist is now output in mi list format.
2718 Fix for gdb/702: a -var-assign that updates the value now shows up
2719 in a subsequent -var-update.
2721 * New native configurations.
2723 FreeBSD/amd64 x86_64-*-freebsd*
2725 * Multi-arched targets.
2727 HP/PA HPUX11 hppa*-*-hpux*
2728 Renesas M32R/D w/simulator m32r-*-elf*
2730 * OBSOLETE configurations and files
2732 Configurations that have been declared obsolete in this release have
2733 been commented out. Unless there is activity to revive these
2734 configurations, the next release of GDB will have their sources
2735 permanently REMOVED.
2737 Z8000 simulator z8k-zilog-none or z8ksim
2738 Matsushita MN10200 w/simulator mn10200-*-*
2739 H8/500 simulator h8500-hitachi-hms or h8500hms
2740 HP/PA running BSD hppa*-*-bsd*
2741 HP/PA running OSF/1 hppa*-*-osf*
2742 HP/PA Pro target hppa*-*-pro*
2743 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2744 Sequent family i[3456]86-sequent-sysv4*
2745 i[3456]86-sequent-sysv*
2746 i[3456]86-sequent-bsd*
2747 Tsqware Sparclet sparclet-*-*
2748 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2750 * REMOVED configurations and files
2753 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2754 IBM AIX PS/2 i[3456]86-*-aix
2755 i386 running Mach 3.0 i[3456]86-*-mach3*
2756 i386 running Mach i[3456]86-*-mach*
2757 i386 running OSF/1 i[3456]86-*osf1mk*
2758 HP/Apollo 68k Family m68*-apollo*-sysv*,
2760 m68*-hp-bsd*, m68*-hp-hpux*
2761 Argonaut Risc Chip (ARC) arc-*-*
2762 Mitsubishi D30V d30v-*-*
2763 Fujitsu FR30 fr30-*-elf*
2764 OS/9000 i[34]86-*-os9k
2765 I960 with MON960 i960-*-coff
2767 * MIPS $fp behavior changed
2769 The convenience variable $fp, for the MIPS, now consistently returns
2770 the address of the current frame's base. Previously, depending on the
2771 context, $fp could refer to either $sp or the current frame's base
2772 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2773 The GNU Source-Level Debugger''.
2775 *** Changes in GDB 5.3:
2777 * GNU/Linux shared library multi-threaded performance improved.
2779 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2780 `/proc', in preference to `ptrace' for memory reads. This may result
2781 in an improvement in the start-up time of multi-threaded, shared
2782 library applications when run under GDB. One GDB user writes: ``loads
2783 shared libs like mad''.
2785 * ``gdbserver'' now supports multi-threaded applications on some targets
2787 Support for debugging multi-threaded applications which use
2788 the GNU/Linux LinuxThreads package has been added for
2789 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2790 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2792 * GDB now supports C/C++ preprocessor macros.
2794 GDB now expands preprocessor macro invocations in C/C++ expressions,
2795 and provides various commands for showing macro definitions and how
2798 The new command `macro expand EXPRESSION' expands any macro
2799 invocations in expression, and shows the result.
2801 The new command `show macro MACRO-NAME' shows the definition of the
2802 macro named MACRO-NAME, and where it was defined.
2804 Most compilers don't include information about macros in the debugging
2805 information by default. In GCC 3.1, for example, you need to compile
2806 your program with the options `-gdwarf-2 -g3'. If the macro
2807 information is present in the executable, GDB will read it.
2809 * Multi-arched targets.
2811 DEC Alpha (partial) alpha*-*-*
2812 DEC VAX (partial) vax-*-*
2814 National Semiconductor NS32000 (partial) ns32k-*-*
2815 Motorola 68000 (partial) m68k-*-*
2816 Motorola MCORE mcore-*-*
2820 Fujitsu FRV architecture added by Red Hat frv*-*-*
2823 * New native configurations
2825 Alpha NetBSD alpha*-*-netbsd*
2826 SH NetBSD sh*-*-netbsdelf*
2827 MIPS NetBSD mips*-*-netbsd*
2828 UltraSPARC NetBSD sparc64-*-netbsd*
2830 * OBSOLETE configurations and files
2832 Configurations that have been declared obsolete in this release have
2833 been commented out. Unless there is activity to revive these
2834 configurations, the next release of GDB will have their sources
2835 permanently REMOVED.
2837 Mitsubishi D30V d30v-*-*
2838 OS/9000 i[34]86-*-os9k
2839 IBM AIX PS/2 i[3456]86-*-aix
2840 Fujitsu FR30 fr30-*-elf*
2841 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2842 Argonaut Risc Chip (ARC) arc-*-*
2843 i386 running Mach 3.0 i[3456]86-*-mach3*
2844 i386 running Mach i[3456]86-*-mach*
2845 i386 running OSF/1 i[3456]86-*osf1mk*
2846 HP/Apollo 68k Family m68*-apollo*-sysv*,
2848 m68*-hp-bsd*, m68*-hp-hpux*
2849 I960 with MON960 i960-*-coff
2851 * OBSOLETE languages
2853 CHILL, a Pascal like language used by telecommunications companies.
2855 * REMOVED configurations and files
2857 AMD 29k family via UDI a29k-amd-udi, udi29k
2858 A29K VxWorks a29k-*-vxworks
2859 AMD 29000 embedded, using EBMON a29k-none-none
2860 AMD 29000 embedded with COFF a29k-none-coff
2861 AMD 29000 embedded with a.out a29k-none-aout
2863 testsuite/gdb.hp/gdb.threads-hp/ directory
2865 * New command "set max-user-call-depth <nnn>"
2867 This command allows the user to limit the call depth of user-defined
2868 commands. The default is 1024.
2870 * Changes in FreeBSD/i386 native debugging.
2872 Support for the "generate-core-file" has been added.
2874 * New commands "dump", "append", and "restore".
2876 These commands allow data to be copied from target memory
2877 to a bfd-format or binary file (dump and append), and back
2878 from a file into memory (restore).
2880 * Improved "next/step" support on multi-processor Alpha Tru64.
2882 The previous single-step mechanism could cause unpredictable problems,
2883 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2884 of a software single-step mechanism prevents this.
2886 *** Changes in GDB 5.2.1:
2894 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2895 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2896 Fix, by Joel Brobecker imported from mainline.
2898 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2899 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2900 Fix, by Fred Fish, imported from mainline.
2902 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2903 Surprisingly enough, it works now.
2904 By Michal Ludvig, imported from mainline.
2906 i386 hardware watchpoint support:
2907 avoid misses on second run for some targets.
2908 By Pierre Muller, imported from mainline.
2910 *** Changes in GDB 5.2:
2912 * New command "set trust-readonly-sections on[off]".
2914 This command is a hint that tells gdb that read-only sections
2915 really are read-only (ie. that their contents will not change).
2916 In this mode, gdb will go to the object file rather than the
2917 target to read memory from read-only sections (such as ".text").
2918 This can be a significant performance improvement on some
2919 (notably embedded) targets.
2921 * New command "generate-core-file" (or "gcore").
2923 This new gdb command allows the user to drop a core file of the child
2924 process state at any time. So far it's been implemented only for
2925 GNU/Linux and Solaris, but should be relatively easily ported to other
2926 hosts. Argument is core file name (defaults to core.<pid>).
2928 * New command line option
2930 GDB now accepts --pid or -p followed by a process id.
2932 * Change in command line behavior -- corefiles vs. process ids.
2934 There is a subtle behavior in the way in which GDB handles
2935 command line arguments. The first non-flag argument is always
2936 a program to debug, but the second non-flag argument may either
2937 be a corefile or a process id. Previously, GDB would attempt to
2938 open the second argument as a corefile, and if that failed, would
2939 issue a superfluous error message and then attempt to attach it as
2940 a process. Now, if the second argument begins with a non-digit,
2941 it will be treated as a corefile. If it begins with a digit,
2942 GDB will attempt to attach it as a process, and if no such process
2943 is found, will then attempt to open it as a corefile.
2945 * Changes in ARM configurations.
2947 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2948 configuration is fully multi-arch.
2950 * New native configurations
2952 ARM NetBSD arm*-*-netbsd*
2953 x86 OpenBSD i[3456]86-*-openbsd*
2954 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2955 Sparc64 running FreeBSD sparc64-*-freebsd*
2959 Sanyo XStormy16 xstormy16-elf
2961 * OBSOLETE configurations and files
2963 Configurations that have been declared obsolete in this release have
2964 been commented out. Unless there is activity to revive these
2965 configurations, the next release of GDB will have their sources
2966 permanently REMOVED.
2968 AMD 29k family via UDI a29k-amd-udi, udi29k
2969 A29K VxWorks a29k-*-vxworks
2970 AMD 29000 embedded, using EBMON a29k-none-none
2971 AMD 29000 embedded with COFF a29k-none-coff
2972 AMD 29000 embedded with a.out a29k-none-aout
2974 testsuite/gdb.hp/gdb.threads-hp/ directory
2976 * REMOVED configurations and files
2978 TI TMS320C80 tic80-*-*
2980 PowerPC Solaris powerpcle-*-solaris*
2981 PowerPC Windows NT powerpcle-*-cygwin32
2982 PowerPC Netware powerpc-*-netware*
2983 Harris/CXUX m88k m88*-harris-cxux*
2984 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2985 ns32k-utek-sysv* ns32k-utek-*
2986 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2987 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2988 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2989 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2990 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2992 * Changes to command line processing
2994 The new `--args' feature can be used to specify command-line arguments
2995 for the inferior from gdb's command line.
2997 * Changes to key bindings
2999 There is a new `operate-and-get-next' function bound to `C-o'.
3001 *** Changes in GDB 5.1.1
3003 Fix compile problem on DJGPP.
3005 Fix a problem with floating-point registers on the i386 being
3008 Fix to stop GDB crashing on .debug_str debug info.
3010 Numerous documentation fixes.
3012 Numerous testsuite fixes.
3014 *** Changes in GDB 5.1:
3016 * New native configurations
3018 Alpha FreeBSD alpha*-*-freebsd*
3019 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3020 MIPS GNU/Linux mips*-*-linux*
3021 MIPS SGI Irix 6.x mips*-sgi-irix6*
3022 ia64 AIX ia64-*-aix*
3023 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3027 Motorola 68HC11 and 68HC12 m68hc11-elf
3029 UltraSparc running GNU/Linux sparc64-*-linux*
3031 * OBSOLETE configurations and files
3033 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3034 Harris/CXUX m88k m88*-harris-cxux*
3035 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3036 ns32k-utek-sysv* ns32k-utek-*
3037 TI TMS320C80 tic80-*-*
3039 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3040 PowerPC Solaris powerpcle-*-solaris*
3041 PowerPC Windows NT powerpcle-*-cygwin32
3042 PowerPC Netware powerpc-*-netware*
3043 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3044 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3045 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3046 Apple Macintosh (MPW) host N/A
3048 stuff.c (Program to stuff files into a specially prepared space in kdb)
3049 kdb-start.c (Main loop for the standalone kernel debugger)
3051 Configurations that have been declared obsolete in this release have
3052 been commented out. Unless there is activity to revive these
3053 configurations, the next release of GDB will have their sources
3054 permanently REMOVED.
3056 * REMOVED configurations and files
3058 Altos 3068 m68*-altos-*
3059 Convex c1-*-*, c2-*-*
3061 ARM RISCix arm-*-* (as host)
3065 * GDB has been converted to ISO C.
3067 GDB's source code has been converted to ISO C. In particular, the
3068 sources are fully protoized, and rely on standard headers being
3073 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3075 * The MI enabled by default.
3077 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3078 revised and enabled by default. Packages which use GDB as a debugging
3079 engine behind a UI or another front end are encouraged to switch to
3080 using the GDB/MI interface, instead of the old annotations interface
3081 which is now deprecated.
3083 * Support for debugging Pascal programs.
3085 GDB now includes support for debugging Pascal programs. The following
3086 main features are supported:
3088 - Pascal-specific data types such as sets;
3090 - automatic recognition of Pascal sources based on file-name
3093 - Pascal-style display of data types, variables, and functions;
3095 - a Pascal expression parser.
3097 However, some important features are not yet supported.
3099 - Pascal string operations are not supported at all;
3101 - there are some problems with boolean types;
3103 - Pascal type hexadecimal constants are not supported
3104 because they conflict with the internal variables format;
3106 - support for Pascal objects and classes is not full yet;
3108 - unlike Pascal, GDB is case-sensitive for symbol names.
3110 * Changes in completion.
3112 Commands such as `shell', `run' and `set args', which pass arguments
3113 to inferior programs, now complete on file names, similar to what
3114 users expect at the shell prompt.
3116 Commands which accept locations, such as `disassemble', `print',
3117 `breakpoint', `until', etc. now complete on filenames as well as
3118 program symbols. Thus, if you type "break foob TAB", and the source
3119 files linked into the programs include `foobar.c', that file name will
3120 be one of the candidates for completion. However, file names are not
3121 considered for completion after you typed a colon that delimits a file
3122 name from a name of a function in that file, as in "break foo.c:bar".
3124 `set demangle-style' completes on available demangling styles.
3126 * New platform-independent commands:
3128 It is now possible to define a post-hook for a command as well as a
3129 hook that runs before the command. For more details, see the
3130 documentation of `hookpost' in the GDB manual.
3132 * Changes in GNU/Linux native debugging.
3134 Support for debugging multi-threaded programs has been completely
3135 revised for all platforms except m68k and sparc. You can now debug as
3136 many threads as your system allows you to have.
3138 Attach/detach is supported for multi-threaded programs.
3140 Support for SSE registers was added for x86. This doesn't work for
3141 multi-threaded programs though.
3143 * Changes in MIPS configurations.
3145 Multi-arch support is enabled for all MIPS configurations.
3147 GDB can now be built as native debugger on SGI Irix 6.x systems for
3148 debugging n32 executables. (Debugging 64-bit executables is not yet
3151 * Unified support for hardware watchpoints in all x86 configurations.
3153 Most (if not all) native x86 configurations support hardware-assisted
3154 breakpoints and watchpoints in a unified manner. This support
3155 implements debug register sharing between watchpoints, which allows to
3156 put a virtually infinite number of watchpoints on the same address,
3157 and also supports watching regions up to 16 bytes with several debug
3160 The new maintenance command `maintenance show-debug-regs' toggles
3161 debugging print-outs in functions that insert, remove, and test
3162 watchpoints and hardware breakpoints.
3164 * Changes in the DJGPP native configuration.
3166 New command ``info dos sysinfo'' displays assorted information about
3167 the CPU, OS, memory, and DPMI server.
3169 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3170 display information about segment descriptors stored in GDT, LDT, and
3173 New commands ``info dos pde'' and ``info dos pte'' display entries
3174 from Page Directory and Page Tables (for now works with CWSDPMI only).
3175 New command ``info dos address-pte'' displays the Page Table entry for
3176 a given linear address.
3178 GDB can now pass command lines longer than 126 characters to the
3179 program being debugged (requires an update to the libdbg.a library
3180 which is part of the DJGPP development kit).
3182 DWARF2 debug info is now supported.
3184 It is now possible to `step' and `next' through calls to `longjmp'.
3186 * Changes in documentation.
3188 All GDB documentation was converted to GFDL, the GNU Free
3189 Documentation License.
3191 Tracepoints-related commands are now fully documented in the GDB
3194 TUI, the Text-mode User Interface, is now documented in the manual.
3196 Tracepoints-related commands are now fully documented in the GDB
3199 The "GDB Internals" manual now has an index. It also includes
3200 documentation of `ui_out' functions, GDB coding standards, x86
3201 hardware watchpoints, and memory region attributes.
3203 * GDB's version number moved to ``version.in''
3205 The Makefile variable VERSION has been replaced by the file
3206 ``version.in''. People creating GDB distributions should update the
3207 contents of this file.
3211 GUD support is now a standard part of the EMACS distribution.
3213 *** Changes in GDB 5.0:
3215 * Improved support for debugging FP programs on x86 targets
3217 Unified and much-improved support for debugging floating-point
3218 programs on all x86 targets. In particular, ``info float'' now
3219 displays the FP registers in the same format on all x86 targets, with
3220 greater level of detail.
3222 * Improvements and bugfixes in hardware-assisted watchpoints
3224 It is now possible to watch array elements, struct members, and
3225 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3226 on x86 targets no longer erroneously trigger when the address is
3229 * Improvements in the native DJGPP version of GDB
3231 The distribution now includes all the scripts and auxiliary files
3232 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3233 machines ``out of the box''.
3235 The DJGPP version can now debug programs that use signals. It is
3236 possible to catch signals that happened in the debuggee, deliver
3237 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3238 would kill the program being debugged.) Programs that hook hardware
3239 interrupts (keyboard, timer, etc.) can also be debugged.
3241 It is now possible to debug DJGPP programs that redirect their
3242 standard handles or switch them to raw (as opposed to cooked) mode, or
3243 even close them. The command ``run < foo > bar'' works as expected,
3244 and ``info terminal'' reports useful information about the debuggee's
3245 terminal, including raw/cooked mode, redirection, etc.
3247 The DJGPP version now uses termios functions for console I/O, which
3248 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3251 DOS-style file names with drive letters are now fully supported by
3254 It is now possible to debug DJGPP programs that switch their working
3255 directory. It is also possible to rerun the debuggee any number of
3256 times without restarting GDB; thus, you can use the same setup,
3257 breakpoints, etc. for many debugging sessions.
3259 * New native configurations
3261 ARM GNU/Linux arm*-*-linux*
3262 PowerPC GNU/Linux powerpc-*-linux*
3266 Motorola MCore mcore-*-*
3267 x86 VxWorks i[3456]86-*-vxworks*
3268 PowerPC VxWorks powerpc-*-vxworks*
3269 TI TMS320C80 tic80-*-*
3271 * OBSOLETE configurations
3273 Altos 3068 m68*-altos-*
3274 Convex c1-*-*, c2-*-*
3276 ARM RISCix arm-*-* (as host)
3279 Configurations that have been declared obsolete will be commented out,
3280 but the code will be left in place. If there is no activity to revive
3281 these configurations before the next release of GDB, the sources will
3282 be permanently REMOVED.
3284 * Gould support removed
3286 Support for the Gould PowerNode and NP1 has been removed.
3288 * New features for SVR4
3290 On SVR4 native platforms (such as Solaris), if you attach to a process
3291 without first loading a symbol file, GDB will now attempt to locate and
3292 load symbols from the running process's executable file.
3294 * Many C++ enhancements
3296 C++ support has been greatly improved. Overload resolution now works properly
3297 in almost all cases. RTTI support is on the way.
3299 * Remote targets can connect to a sub-program
3301 A popen(3) style serial-device has been added. This device starts a
3302 sub-process (such as a stand-alone simulator) and then communicates
3303 with that. The sub-program to run is specified using the syntax
3304 ``|<program> <args>'' vis:
3306 (gdb) set remotedebug 1
3307 (gdb) target extended-remote |mn10300-elf-sim program-args
3309 * MIPS 64 remote protocol
3311 A long standing bug in the mips64 remote protocol where by GDB
3312 expected certain 32 bit registers (ex SR) to be transfered as 32
3313 instead of 64 bits has been fixed.
3315 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3316 added to provide backward compatibility with older versions of GDB.
3318 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3320 The command ``set remotebinarydownload'' command has been replaced by
3321 ``set remote X-packet''. Other commands in ``set remote'' family
3322 include ``set remote P-packet''.
3324 * Breakpoint commands accept ranges.
3326 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3327 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3328 ``tracepoint passcount'' also accepts a range of tracepoints.
3330 * ``apropos'' command added.
3332 The ``apropos'' command searches through command names and
3333 documentation strings, printing out matches, making it much easier to
3334 try to find a command that does what you are looking for.
3338 A new machine oriented interface (MI) has been added to GDB. This
3339 interface is designed for debug environments running GDB as a separate
3340 process. This is part of the long term libGDB project. See the
3341 "GDB/MI" chapter of the GDB manual for further information. It can be
3342 enabled by configuring with:
3344 .../configure --enable-gdbmi
3346 *** Changes in GDB-4.18:
3348 * New native configurations
3350 HP-UX 10.20 hppa*-*-hpux10.20
3351 HP-UX 11.x hppa*-*-hpux11.0*
3352 M68K GNU/Linux m68*-*-linux*
3356 Fujitsu FR30 fr30-*-elf*
3357 Intel StrongARM strongarm-*-*
3358 Mitsubishi D30V d30v-*-*
3360 * OBSOLETE configurations
3362 Gould PowerNode, NP1 np1-*-*, pn-*-*
3364 Configurations that have been declared obsolete will be commented out,
3365 but the code will be left in place. If there is no activity to revive
3366 these configurations before the next release of GDB, the sources will
3367 be permanently REMOVED.
3371 As a compatibility experiment, GDB's source files buildsym.h and
3372 buildsym.c have been converted to pure standard C, no longer
3373 containing any K&R compatibility code. We believe that all systems in
3374 use today either come with a standard C compiler, or have a GCC port
3375 available. If this is not true, please report the affected
3376 configuration to bug-gdb@gnu.org immediately. See the README file for
3377 information about getting a standard C compiler if you don't have one
3382 GDB now uses readline 2.2.
3384 * set extension-language
3386 You can now control the mapping between filename extensions and source
3387 languages by using the `set extension-language' command. For instance,
3388 you can ask GDB to treat .c files as C++ by saying
3389 set extension-language .c c++
3390 The command `info extensions' lists all of the recognized extensions
3391 and their associated languages.
3393 * Setting processor type for PowerPC and RS/6000
3395 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3396 you can use the `set processor' command to specify what variant of the
3397 PowerPC family you are debugging. The command
3401 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3402 following PowerPC and RS6000 variants:
3404 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3405 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3407 403GC IBM PowerPC 403GC
3408 505 Motorola PowerPC 505
3409 860 Motorola PowerPC 860 or 850
3410 601 Motorola PowerPC 601
3411 602 Motorola PowerPC 602
3412 603 Motorola/IBM PowerPC 603 or 603e
3413 604 Motorola PowerPC 604 or 604e
3414 750 Motorola/IBM PowerPC 750 or 750
3416 At the moment, this command just tells GDB what to name the
3417 special-purpose processor registers. Since almost all the affected
3418 registers are inaccessible to user-level programs, this command is
3419 only useful for remote debugging in its present form.
3423 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3424 more extensive support for HP-UX. Added features include shared
3425 library support, kernel threads and hardware watchpoints for 11.00,
3426 support for HP's ANSI C and C++ compilers, and a compatibility mode
3427 for xdb and dbx commands.
3431 HP's donation includes the new concept of catchpoints, which is a
3432 generalization of the old catch command. On HP-UX, it is now possible
3433 to catch exec, fork, and vfork, as well as library loading.
3435 This means that the existing catch command has changed; its first
3436 argument now specifies the type of catch to be set up. See the
3437 output of "help catch" for a list of catchpoint types.
3439 * Debugging across forks
3441 On HP-UX, you can choose which process to debug when a fork() happens
3446 HP has donated a curses-based terminal user interface (TUI). To get
3447 it, build with --enable-tui. Although this can be enabled for any
3448 configuration, at present it only works for native HP debugging.
3450 * GDB remote protocol additions
3452 A new protocol packet 'X' that writes binary data is now available.
3453 Default behavior is to try 'X', then drop back to 'M' if the stub
3454 fails to respond. The settable variable `remotebinarydownload'
3455 allows explicit control over the use of 'X'.
3457 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3458 full 64-bit address. The command
3460 set remoteaddresssize 32
3462 can be used to revert to the old behaviour. For existing remote stubs
3463 the change should not be noticed, as the additional address information
3466 In order to assist in debugging stubs, you may use the maintenance
3467 command `packet' to send any text string to the stub. For instance,
3469 maint packet heythere
3471 sends the packet "$heythere#<checksum>". Note that it is very easy to
3472 disrupt a debugging session by sending the wrong packet at the wrong
3475 The compare-sections command allows you to compare section data on the
3476 target to what is in the executable file without uploading or
3477 downloading, by comparing CRC checksums.
3479 * Tracing can collect general expressions
3481 You may now collect general expressions at tracepoints. This requires
3482 further additions to the target-side stub; see tracepoint.c and
3483 doc/agentexpr.texi for further details.
3485 * mask-address variable for Mips
3487 For Mips targets, you may control the zeroing of the upper 32 bits of
3488 a 64-bit address by entering `set mask-address on'. This is mainly
3489 of interest to users of embedded R4xxx and R5xxx processors.
3491 * Higher serial baud rates
3493 GDB's serial code now allows you to specify baud rates 57600, 115200,
3494 230400, and 460800 baud. (Note that your host system may not be able
3495 to achieve all of these rates.)
3499 The i960 configuration now includes an initial implementation of a
3500 builtin simulator, contributed by Jim Wilson.
3503 *** Changes in GDB-4.17:
3505 * New native configurations
3507 Alpha GNU/Linux alpha*-*-linux*
3508 Unixware 2.x i[3456]86-unixware2*
3509 Irix 6.x mips*-sgi-irix6*
3510 PowerPC GNU/Linux powerpc-*-linux*
3511 PowerPC Solaris powerpcle-*-solaris*
3512 Sparc GNU/Linux sparc-*-linux*
3513 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3517 Argonaut Risc Chip (ARC) arc-*-*
3518 Hitachi H8/300S h8300*-*-*
3519 Matsushita MN10200 w/simulator mn10200-*-*
3520 Matsushita MN10300 w/simulator mn10300-*-*
3521 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3522 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3523 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3524 Mitsubishi D10V w/simulator d10v-*-*
3525 Mitsubishi M32R/D w/simulator m32r-*-elf*
3526 Tsqware Sparclet sparclet-*-*
3527 NEC V850 w/simulator v850-*-*
3529 * New debugging protocols
3531 ARM with RDI protocol arm*-*-*
3532 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3533 DDB and LSI variants of PMON protocol mips*-*-*
3534 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3535 PowerPC with SDS protocol powerpc{,le}-*-eabi
3536 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3540 All configurations can now understand and use the DWARF 2 debugging
3541 format. The choice is automatic, if the symbol file contains DWARF 2
3546 GDB now includes basic Java language support. This support is
3547 only useful with Java compilers that produce native machine code.
3549 * solib-absolute-prefix and solib-search-path
3551 For SunOS and SVR4 shared libraries, you may now set the prefix for
3552 loading absolute shared library symbol files, and the search path for
3553 locating non-absolute shared library symbol files.
3555 * Live range splitting
3557 GDB can now effectively debug code for which GCC has performed live
3558 range splitting as part of its optimization. See gdb/doc/LRS for
3559 more details on the expected format of the stabs information.
3563 GDB's support for the GNU Hurd, including thread debugging, has been
3564 updated to work with current versions of the Hurd.
3568 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3569 instruction set. ARM GDB automatically detects when Thumb
3570 instructions are in use, and adjusts disassembly and backtracing
3575 GDB's MIPS target configurations now handle the MIP16 16-bit
3580 GDB now includes support for overlays; if an executable has been
3581 linked such that multiple sections are based at the same address, GDB
3582 will decide which section to use for symbolic info. You can choose to
3583 control the decision manually, using overlay commands, or implement
3584 additional target-side support and use "overlay load-target" to bring
3585 in the overlay mapping. Do "help overlay" for more detail.
3589 The command "info symbol <address>" displays information about
3590 the symbol at the specified address.
3594 The standard remote protocol now includes an extension that allows
3595 asynchronous collection and display of trace data. This requires
3596 extensive support in the target-side debugging stub. Tracing mode
3597 includes a new interaction mode in GDB and new commands: see the
3598 file tracepoint.c for more details.
3602 Configurations for embedded MIPS now include a simulator contributed
3603 by Cygnus Solutions. The simulator supports the instruction sets
3604 of most MIPS variants.
3608 Sparc configurations may now include the ERC32 simulator contributed
3609 by the European Space Agency. The simulator is not built into
3610 Sparc targets by default; configure with --enable-sim to include it.
3614 For target configurations that may include multiple variants of a
3615 basic architecture (such as MIPS and SH), you may now set the
3616 architecture explicitly. "set arch" sets, "info arch" lists
3617 the possible architectures.
3619 *** Changes in GDB-4.16:
3621 * New native configurations
3623 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3624 M68K NetBSD m68k-*-netbsd*
3625 PowerPC AIX 4.x powerpc-*-aix*
3626 PowerPC MacOS powerpc-*-macos*
3627 PowerPC Windows NT powerpcle-*-cygwin32
3628 RS/6000 AIX 4.x rs6000-*-aix4*
3632 ARM with RDP protocol arm-*-*
3633 I960 with MON960 i960-*-coff
3634 MIPS VxWorks mips*-*-vxworks*
3635 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3636 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3638 Matra Sparclet sparclet-*-*
3642 The powerpc-eabi configuration now includes the PSIM simulator,
3643 contributed by Andrew Cagney, with assistance from Mike Meissner.
3644 PSIM is a very elaborate model of the PowerPC, including not only
3645 basic instruction set execution, but also details of execution unit
3646 performance and I/O hardware. See sim/ppc/README for more details.
3650 GDB now works with Solaris 2.5.
3652 * Windows 95/NT native
3654 GDB will now work as a native debugger on Windows 95 and Windows NT.
3655 To build it from source, you must use the "gnu-win32" environment,
3656 which uses a DLL to emulate enough of Unix to run the GNU tools.
3657 Further information, binaries, and sources are available at
3658 ftp.cygnus.com, under pub/gnu-win32.
3660 * dont-repeat command
3662 If a user-defined command includes the command `dont-repeat', then the
3663 command will not be repeated if the user just types return. This is
3664 useful if the command is time-consuming to run, so that accidental
3665 extra keystrokes don't run the same command many times.
3667 * Send break instead of ^C
3669 The standard remote protocol now includes an option to send a break
3670 rather than a ^C to the target in order to interrupt it. By default,
3671 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3673 * Remote protocol timeout
3675 The standard remote protocol includes a new variable `remotetimeout'
3676 that allows you to set the number of seconds before GDB gives up trying
3677 to read from the target. The default value is 2.
3679 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3681 By default GDB will automatically keep track of objects as they are
3682 loaded and unloaded by the dynamic linker. By using the command `set
3683 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3684 when shared library events occur, thus allowing you to set breakpoints
3685 in shared libraries which are explicitly loaded by the inferior.
3687 Note this feature does not work on hpux8. On hpux9 you must link
3688 /usr/lib/end.o into your program. This feature should work
3689 automatically on hpux10.
3691 * Irix 5.x hardware watchpoint support
3693 Irix 5 configurations now support the use of hardware watchpoints.
3695 * Mips protocol "SYN garbage limit"
3697 When debugging a Mips target using the `target mips' protocol, you
3698 may set the number of characters that GDB will ignore by setting
3699 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3700 every character. The default value is 1050.
3702 * Recording and replaying remote debug sessions
3704 If you set `remotelogfile' to the name of a file, gdb will write to it
3705 a recording of a remote debug session. This recording may then be
3706 replayed back to gdb using "gdbreplay". See gdbserver/README for
3707 details. This is useful when you have a problem with GDB while doing
3708 remote debugging; you can make a recording of the session and send it
3709 to someone else, who can then recreate the problem.
3711 * Speedups for remote debugging
3713 GDB includes speedups for downloading and stepping MIPS systems using
3714 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3715 and more efficient S-record downloading.
3717 * Memory use reductions and statistics collection
3719 GDB now uses less memory and reports statistics about memory usage.
3720 Try the `maint print statistics' command, for example.
3722 *** Changes in GDB-4.15:
3724 * Psymtabs for XCOFF
3726 The symbol reader for AIX GDB now uses partial symbol tables. This
3727 can greatly improve startup time, especially for large executables.
3729 * Remote targets use caching
3731 Remote targets now use a data cache to speed up communication with the
3732 remote side. The data cache could lead to incorrect results because
3733 it doesn't know about volatile variables, thus making it impossible to
3734 debug targets which use memory mapped I/O devices. `set remotecache
3735 off' turns the the data cache off.
3737 * Remote targets may have threads
3739 The standard remote protocol now includes support for multiple threads
3740 in the target system, using new protocol commands 'H' and 'T'. See
3741 gdb/remote.c for details.
3745 If GDB is configured with `--enable-netrom', then it will include
3746 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3747 acts as though it is a bank of ROM on the target board, but you can
3748 write into it over the network. GDB's support consists only of
3749 support for fast loading into the emulated ROM; to debug, you must use
3750 another protocol, such as standard remote protocol. The usual
3751 sequence is something like
3753 target nrom <netrom-hostname>
3755 target remote <netrom-hostname>:1235
3759 GDB now includes support for the Apple Macintosh, as a host only. It
3760 may be run as either an MPW tool or as a standalone application, and
3761 it can debug through the serial port. All the usual GDB commands are
3762 available, but to the target command, you must supply "serial" as the
3763 device type instead of "/dev/ttyXX". See mpw-README in the main
3764 directory for more information on how to build. The MPW configuration
3765 scripts */mpw-config.in support only a few targets, and only the
3766 mips-idt-ecoff target has been tested.
3770 GDB configuration now uses autoconf. This is not user-visible,
3771 but does simplify configuration and building.
3775 GDB now supports hpux10.
3777 *** Changes in GDB-4.14:
3779 * New native configurations
3781 x86 FreeBSD i[345]86-*-freebsd
3782 x86 NetBSD i[345]86-*-netbsd
3783 NS32k NetBSD ns32k-*-netbsd
3784 Sparc NetBSD sparc-*-netbsd
3788 A29K VxWorks a29k-*-vxworks
3789 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3790 CPU32 EST-300 emulator m68*-*-est*
3791 PowerPC ELF powerpc-*-elf
3794 * Alpha OSF/1 support for procfs
3796 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3797 possible to attach to running processes. As the mounting of the /proc
3798 filesystem is optional on the Alpha, GDB automatically determines
3799 the availability of /proc during startup. This can lead to problems
3800 if /proc is unmounted after GDB has been started.
3802 * Arguments to user-defined commands
3804 User commands may accept up to 10 arguments separated by whitespace.
3805 Arguments are accessed within the user command via $arg0..$arg9. A
3808 print $arg0 + $arg1 + $arg2
3810 To execute the command use:
3813 Defines the command "adder" which prints the sum of its three arguments.
3814 Note the arguments are text substitutions, so they may reference variables,
3815 use complex expressions, or even perform inferior function calls.
3817 * New `if' and `while' commands
3819 This makes it possible to write more sophisticated user-defined
3820 commands. Both commands take a single argument, which is the
3821 expression to evaluate, and must be followed by the commands to
3822 execute, one per line, if the expression is nonzero, the list being
3823 terminated by the word `end'. The `if' command list may include an
3824 `else' word, which causes the following commands to be executed only
3825 if the expression is zero.
3827 * Fortran source language mode
3829 GDB now includes partial support for Fortran 77. It will recognize
3830 Fortran programs and can evaluate a subset of Fortran expressions, but
3831 variables and functions may not be handled correctly. GDB will work
3832 with G77, but does not yet know much about symbols emitted by other
3835 * Better HPUX support
3837 Most debugging facilities now work on dynamic executables for HPPAs
3838 running hpux9 or later. You can attach to running dynamically linked
3839 processes, but by default the dynamic libraries will be read-only, so
3840 for instance you won't be able to put breakpoints in them. To change
3841 that behavior do the following before running the program:
3847 This will cause the libraries to be mapped private and read-write.
3848 To revert to the normal behavior, do this:
3854 You cannot set breakpoints or examine data in the library until after
3855 the library is loaded if the function/data symbols do not have
3858 GDB can now also read debug symbols produced by the HP C compiler on
3859 HPPAs (sorry, no C++, Fortran or 68k support).
3861 * Target byte order now dynamically selectable
3863 You can choose which byte order to use with a target system, via the
3864 commands "set endian big" and "set endian little", and you can see the
3865 current setting by using "show endian". You can also give the command
3866 "set endian auto", in which case GDB will use the byte order
3867 associated with the executable. Currently, only embedded MIPS
3868 configurations support dynamic selection of target byte order.
3870 * New DOS host serial code
3872 This version uses DPMI interrupts to handle buffered I/O, so you
3873 no longer need to run asynctsr when debugging boards connected to
3876 *** Changes in GDB-4.13:
3878 * New "complete" command
3880 This lists all the possible completions for the rest of the line, if it
3881 were to be given as a command itself. This is intended for use by emacs.
3883 * Trailing space optional in prompt
3885 "set prompt" no longer adds a space for you after the prompt you set. This
3886 allows you to set a prompt which ends in a space or one that does not.
3888 * Breakpoint hit counts
3890 "info break" now displays a count of the number of times the breakpoint
3891 has been hit. This is especially useful in conjunction with "ignore"; you
3892 can ignore a large number of breakpoint hits, look at the breakpoint info
3893 to see how many times the breakpoint was hit, then run again, ignoring one
3894 less than that number, and this will get you quickly to the last hit of
3897 * Ability to stop printing at NULL character
3899 "set print null-stop" will cause GDB to stop printing the characters of
3900 an array when the first NULL is encountered. This is useful when large
3901 arrays actually contain only short strings.
3903 * Shared library breakpoints
3905 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3906 breakpoints in shared libraries before the executable is run.
3908 * Hardware watchpoints
3910 There is a new hardware breakpoint for the watch command for sparclite
3911 targets. See gdb/sparclite/hw_breakpoint.note.
3913 Hardware watchpoints are also now supported under GNU/Linux.
3917 Annotations have been added. These are for use with graphical interfaces,
3918 and are still experimental. Currently only gdba.el uses these.
3920 * Improved Irix 5 support
3922 GDB now works properly with Irix 5.2.
3924 * Improved HPPA support
3926 GDB now works properly with the latest GCC and GAS.
3928 * New native configurations
3930 Sequent PTX4 i[34]86-sequent-ptx4
3931 HPPA running OSF/1 hppa*-*-osf*
3932 Atari TT running SVR4 m68*-*-sysv4*
3933 RS/6000 LynxOS rs6000-*-lynxos*
3937 OS/9000 i[34]86-*-os9k
3938 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3941 * Hitachi SH7000 and E7000-PC ICE support
3943 There is now support for communicating with the Hitachi E7000-PC ICE.
3944 This is available automatically when GDB is configured for the SH.
3948 As usual, a variety of small fixes and improvements, both generic
3949 and configuration-specific. See the ChangeLog for more detail.
3951 *** Changes in GDB-4.12:
3953 * Irix 5 is now supported
3957 GDB-4.12 on the HPPA has a number of changes which make it unable
3958 to debug the output from the currently released versions of GCC and
3959 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3960 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3961 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3964 *** Changes in GDB-4.11:
3966 * User visible changes:
3970 The "set remotedebug" option is now consistent between the mips remote
3971 target, remote targets using the gdb-specific protocol, UDI (AMD's
3972 debug protocol for the 29k) and the 88k bug monitor. It is now an
3973 integer specifying a debug level (normally 0 or 1, but 2 means more
3974 debugging info for the mips target).
3976 * DEC Alpha native support
3978 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3979 debug info, but GDB works fairly well with the DEC compiler and should
3980 work with a future GCC release. See the README file for a few
3981 Alpha-specific notes.
3983 * Preliminary thread implementation
3985 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3987 * LynxOS native and target support for 386
3989 This release has been hosted on LynxOS 2.2, and also can be configured
3990 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3993 * Improvements in C++ mangling/demangling.
3995 This release has much better g++ debugging, specifically in name
3996 mangling/demangling, virtual function calls, print virtual table,
3997 call methods, ...etc.
3999 *** Changes in GDB-4.10:
4001 * User visible changes:
4003 Remote debugging using the GDB-specific (`target remote') protocol now
4004 supports the `load' command. This is only useful if you have some
4005 other way of getting the stub to the target system, and you can put it
4006 somewhere in memory where it won't get clobbered by the download.
4008 Filename completion now works.
4010 When run under emacs mode, the "info line" command now causes the
4011 arrow to point to the line specified. Also, "info line" prints
4012 addresses in symbolic form (as well as hex).
4014 All vxworks based targets now support a user settable option, called
4015 vxworks-timeout. This option represents the number of seconds gdb
4016 should wait for responses to rpc's. You might want to use this if
4017 your vxworks target is, perhaps, a slow software simulator or happens
4018 to be on the far side of a thin network line.
4022 This release contains support for using a DEC alpha as a GDB host for
4023 cross debugging. Native alpha debugging is not supported yet.
4026 *** Changes in GDB-4.9:
4030 This is the first GDB release which is accompanied by a matching testsuite.
4031 The testsuite requires installation of dejagnu, which should be available
4032 via ftp from most sites that carry GNU software.
4036 'Cfront' style demangling has had its name changed to 'ARM' style, to
4037 emphasize that it was written from the specifications in the C++ Annotated
4038 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4039 disclaimers, it still generated too much confusion with users attempting to
4040 use gdb with AT&T cfront.
4044 GDB now uses a standard remote interface to a simulator library.
4045 So far, the library contains simulators for the Zilog Z8001/2, the
4046 Hitachi H8/300, H8/500 and Super-H.
4048 * New targets supported
4050 H8/300 simulator h8300-hitachi-hms or h8300hms
4051 H8/500 simulator h8500-hitachi-hms or h8500hms
4052 SH simulator sh-hitachi-hms or sh
4053 Z8000 simulator z8k-zilog-none or z8ksim
4054 IDT MIPS board over serial line mips-idt-ecoff
4056 Cross-debugging to GO32 targets is supported. It requires a custom
4057 version of the i386-stub.c module which is integrated with the
4058 GO32 memory extender.
4060 * New remote protocols
4062 MIPS remote debugging protocol.
4064 * New source languages supported
4066 This version includes preliminary support for Chill, a Pascal like language
4067 used by telecommunications companies. Chill support is also being integrated
4068 into the GNU compiler, but we don't know when it will be publically available.
4071 *** Changes in GDB-4.8:
4073 * HP Precision Architecture supported
4075 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4076 version of this support was available as a set of patches from the
4077 University of Utah. GDB does not support debugging of programs
4078 compiled with the HP compiler, because HP will not document their file
4079 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4080 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4082 Many problems in the preliminary version have been fixed.
4084 * Faster and better demangling
4086 We have improved template demangling and fixed numerous bugs in the GNU style
4087 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4088 character types (wchar_t) are now supported. Demangling of each symbol is now
4089 only done once, and is cached when the symbol table for a file is read in.
4090 This results in a small increase in memory usage for C programs, a moderate
4091 increase in memory usage for C++ programs, and a fantastic speedup in
4094 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4095 from the specifications in the Annotated Reference Manual, which AT&T's
4096 compiler does not actually implement.
4098 * G++ multiple inheritance compiler problem
4100 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4101 inheritance lattices was reworked to properly discover ambiguities. We
4102 recently found an example which causes this new algorithm to fail in a
4103 very subtle way, producing bad debug information for those classes.
4104 The file 'gcc.patch' (in this directory) can be applied to gcc to
4105 circumvent the problem. A future GCC release will contain a complete
4108 The previous G++ debug info problem (mentioned below for the gdb-4.7
4109 release) is fixed in gcc version 2.3.2.
4111 * Improved configure script
4113 The `configure' script will now attempt to guess your system type if
4114 you don't supply a host system type. The old scheme of supplying a
4115 host system triplet is preferable over using this. All the magic is
4116 done in the new `config.guess' script. Examine it for details.
4118 We have also brought our configure script much more in line with the FSF's
4119 version. It now supports the --with-xxx options. In particular,
4120 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4121 The resulting GDB will not be able to read arbitrary object file formats --
4122 only the format ``expected'' to be used on the configured target system.
4123 We hope to make this the default in a future release.
4125 * Documentation improvements
4127 There's new internal documentation on how to modify GDB, and how to
4128 produce clean changes to the code. We implore people to read it
4129 before submitting changes.
4131 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4132 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4133 `info' files are also provided. To build `info' files from scratch,
4134 you will need the latest `makeinfo' release, which will be available in
4135 a future texinfo-X.Y release.
4137 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4138 We're not sure exactly which versions have this problem, but it has
4139 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4140 or better. If that isn't possible, there is a patch in
4141 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4142 around this problem.
4146 GDB now supports array constants that can be used in expressions typed in by
4147 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4148 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4151 The new directory `gdb/sparclite' contains a program that demonstrates
4152 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4154 * New native hosts supported
4156 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4157 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4159 * New targets supported
4161 AMD 29k family via UDI a29k-amd-udi or udi29k
4163 * New file formats supported
4165 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4166 HPUX core files, and SCO 3.2v2 core files.
4170 Attaching to processes now works again; thanks for the many bug reports.
4172 We have also stomped on a bunch of core dumps caused by
4173 printf_filtered("%s") problems.
4175 We eliminated a copyright problem on the rpc and ptrace header files
4176 for VxWorks, which was discovered at the last minute during the 4.7
4177 release. You should now be able to build a VxWorks GDB.
4179 You can now interrupt gdb while an attached process is running. This
4180 will cause the attached process to stop, and give control back to GDB.
4182 We fixed problems caused by using too many file descriptors
4183 for reading symbols from object files and libraries. This was
4184 especially a problem for programs that used many (~100) shared
4187 The `step' command now only enters a subroutine if there is line number
4188 information for the subroutine. Otherwise it acts like the `next'
4189 command. Previously, `step' would enter subroutines if there was
4190 any debugging information about the routine. This avoids problems
4191 when using `cc -g1' on MIPS machines.
4193 * Internal improvements
4195 GDB's internal interfaces have been improved to make it easier to support
4196 debugging of multiple languages in the future.
4198 GDB now uses a common structure for symbol information internally.
4199 Minimal symbols (derived from linkage symbols in object files), partial
4200 symbols (from a quick scan of debug information), and full symbols
4201 contain a common subset of information, making it easier to write
4202 shared code that handles any of them.
4204 * New command line options
4206 We now accept --silent as an alias for --quiet.
4210 The memory-mapped-malloc library is now licensed under the GNU Library
4211 General Public License.
4213 *** Changes in GDB-4.7:
4215 * Host/native/target split
4217 GDB has had some major internal surgery to untangle the support for
4218 hosts and remote targets. Now, when you configure GDB for a remote
4219 target, it will no longer load in all of the support for debugging
4220 local programs on the host. When fully completed and tested, this will
4221 ensure that arbitrary host/target combinations are possible.
4223 The primary conceptual shift is to separate the non-portable code in
4224 GDB into three categories. Host specific code is required any time GDB
4225 is compiled on that host, regardless of the target. Target specific
4226 code relates to the peculiarities of the target, but can be compiled on
4227 any host. Native specific code is everything else: it can only be
4228 built when the host and target are the same system. Child process
4229 handling and core file support are two common `native' examples.
4231 GDB's use of /proc for controlling Unix child processes is now cleaner.
4232 It has been split out into a single module under the `target_ops' vector,
4233 plus two native-dependent functions for each system that uses /proc.
4235 * New hosts supported
4237 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4238 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4239 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4241 * New targets supported
4243 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4244 68030 and CPU32 m68030-*-*, m68332-*-*
4246 * New native hosts supported
4248 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4249 (386bsd is not well tested yet)
4250 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4252 * New file formats supported
4254 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4255 supports reading of `a.out.adobe' object files, which are an a.out
4256 format extended with minimal information about multiple sections.
4260 `show copying' is the same as the old `info copying'.
4261 `show warranty' is the same as `info warrantee'.
4262 These were renamed for consistency. The old commands continue to work.
4264 `info handle' is a new alias for `info signals'.
4266 You can now define pre-command hooks, which attach arbitrary command
4267 scripts to any command. The commands in the hook will be executed
4268 prior to the user's command. You can also create a hook which will be
4269 executed whenever the program stops. See gdb.texinfo.
4273 We now deal with Cfront style name mangling, and can even extract type
4274 info from mangled symbols. GDB can automatically figure out which
4275 symbol mangling style your C++ compiler uses.
4277 Calling of methods and virtual functions has been improved as well.
4281 The crash that occured when debugging Sun Ansi-C compiled binaries is
4282 fixed. This was due to mishandling of the extra N_SO stabs output
4285 We also finally got Ultrix 4.2 running in house, and fixed core file
4286 support, with help from a dozen people on the net.
4288 John M. Farrell discovered that the reason that single-stepping was so
4289 slow on all of the Mips based platforms (primarily SGI and DEC) was
4290 that we were trying to demangle and lookup a symbol used for internal
4291 purposes on every instruction that was being stepped through. Changing
4292 the name of that symbol so that it couldn't be mistaken for a C++
4293 mangled symbol sped things up a great deal.
4295 Rich Pixley sped up symbol lookups in general by getting much smarter
4296 about when C++ symbol mangling is necessary. This should make symbol
4297 completion (TAB on the command line) much faster. It's not as fast as
4298 we'd like, but it's significantly faster than gdb-4.6.
4302 A new user controllable variable 'call_scratch_address' can
4303 specify the location of a scratch area to be used when GDB
4304 calls a function in the target. This is necessary because the
4305 usual method of putting the scratch area on the stack does not work
4306 in systems that have separate instruction and data spaces.
4308 We integrated changes to support the 29k UDI (Universal Debugger
4309 Interface), but discovered at the last minute that we didn't have all
4310 of the appropriate copyright paperwork. We are working with AMD to
4311 resolve this, and hope to have it available soon.
4315 We have sped up the remote serial line protocol, especially for targets
4316 with lots of registers. It now supports a new `expedited status' ('T')
4317 message which can be used in place of the existing 'S' status message.
4318 This allows the remote stub to send only the registers that GDB
4319 needs to make a quick decision about single-stepping or conditional
4320 breakpoints, eliminating the need to fetch the entire register set for
4321 each instruction being stepped through.
4323 The GDB remote serial protocol now implements a write-through cache for
4324 registers, only re-reading the registers if the target has run.
4326 There is also a new remote serial stub for SPARC processors. You can
4327 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4328 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4329 processor with a serial port.
4333 Configure.in files have become much easier to read and modify. A new
4334 `table driven' format makes it more obvious what configurations are
4335 supported, and what files each one uses.
4339 There is a new opcodes library which will eventually contain all of the
4340 disassembly routines and opcode tables. At present, it only contains
4341 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4342 disassembler (binutils/objdump) to share these routines.
4344 The libiberty library is now copylefted under the GNU Library General
4345 Public License. This allows more liberal use, and was done so libg++
4346 can use it. This makes no difference to GDB, since the Library License
4347 grants all the rights from the General Public License.
4351 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4352 reference to the stabs symbol info used by the debugger. It is (as far
4353 as we know) the only published document on this fascinating topic. We
4354 encourage you to read it, compare it to the stabs information on your
4355 system, and send improvements on the document in general (to
4356 bug-gdb@prep.ai.mit.edu).
4358 And, of course, many bugs have been fixed.
4361 *** Changes in GDB-4.6:
4363 * Better support for C++ function names
4365 GDB now accepts as input the "demangled form" of C++ overloaded function
4366 names and member function names, and can do command completion on such names
4367 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4368 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4369 Make use of command completion, it is your friend.
4371 GDB also now accepts a variety of C++ mangled symbol formats. They are
4372 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4373 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4374 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4375 for the list of formats.
4377 * G++ symbol mangling problem
4379 Recent versions of gcc have a bug in how they emit debugging information for
4380 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4381 directory) can be applied to gcc to fix the problem. Alternatively, if you
4382 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4383 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4384 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4387 * New 'maintenance' command
4389 All of the commands related to hacking GDB internals have been moved out of
4390 the main command set, and now live behind the 'maintenance' command. This
4391 can also be abbreviated as 'mt'. The following changes were made:
4393 dump-me -> maintenance dump-me
4394 info all-breakpoints -> maintenance info breakpoints
4395 printmsyms -> maintenance print msyms
4396 printobjfiles -> maintenance print objfiles
4397 printpsyms -> maintenance print psymbols
4398 printsyms -> maintenance print symbols
4400 The following commands are new:
4402 maintenance demangle Call internal GDB demangler routine to
4403 demangle a C++ link name and prints the result.
4404 maintenance print type Print a type chain for a given symbol
4406 * Change to .gdbinit file processing
4408 We now read the $HOME/.gdbinit file before processing the argv arguments
4409 (e.g. reading symbol files or core files). This allows global parameters to
4410 be set, which will apply during the symbol reading. The ./.gdbinit is still
4411 read after argv processing.
4413 * New hosts supported
4415 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4417 GNU/Linux support i386-unknown-linux or linux
4419 We are also including code to support the HP/PA running BSD and HPUX. This
4420 is almost guaranteed not to work, as we didn't have time to test or build it
4421 for this release. We are including it so that the more adventurous (or
4422 masochistic) of you can play with it. We also had major problems with the
4423 fact that the compiler that we got from HP doesn't support the -g option.
4426 * New targets supported
4428 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4430 * More smarts about finding #include files
4432 GDB now remembers the compilation directory for all include files, and for
4433 all files from which C is generated (like yacc and lex sources). This
4434 greatly improves GDB's ability to find yacc/lex sources, and include files,
4435 especially if you are debugging your program from a directory different from
4436 the one that contains your sources.
4438 We also fixed a bug which caused difficulty with listing and setting
4439 breakpoints in include files which contain C code. (In the past, you had to
4440 try twice in order to list an include file that you hadn't looked at before.)
4442 * Interesting infernals change
4444 GDB now deals with arbitrary numbers of sections, where the symbols for each
4445 section must be relocated relative to that section's landing place in the
4446 target's address space. This work was needed to support ELF with embedded
4447 stabs used by Solaris-2.0.
4449 * Bug fixes (of course!)
4451 There have been loads of fixes for the following things:
4452 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4453 i960, stabs, DOS(GO32), procfs, etc...
4455 See the ChangeLog for details.
4457 *** Changes in GDB-4.5:
4459 * New machines supported (host and target)
4461 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4463 SGI Irix-4.x mips-sgi-irix4 or iris4
4465 * New malloc package
4467 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4468 Mmalloc is capable of handling mutiple heaps of memory. It is also
4469 capable of saving a heap to a file, and then mapping it back in later.
4470 This can be used to greatly speedup the startup of GDB by using a
4471 pre-parsed symbol table which lives in a mmalloc managed heap. For
4472 more details, please read mmalloc/mmalloc.texi.
4476 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4477 'help info proc' for details.
4479 * MIPS ecoff symbol table format
4481 The code that reads MIPS symbol table format is now supported on all hosts.
4482 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4485 * File name changes for MS-DOS
4487 Many files in the config directories have been renamed to make it easier to
4488 support GDB on MS-DOSe systems (which have very restrictive file name
4489 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4490 environment) is close to working but has some remaining problems. Note
4491 that debugging of DOS programs is not supported, due to limitations
4492 in the ``operating system'', but it can be used to host cross-debugging.
4494 * Cross byte order fixes
4496 Many fixes have been made to support cross debugging of Sparc and MIPS
4497 targets from hosts whose byte order differs.
4499 * New -mapped and -readnow options
4501 If memory-mapped files are available on your system through the 'mmap'
4502 system call, you can use the -mapped option on the `file' or
4503 `symbol-file' commands to cause GDB to write the symbols from your
4504 program into a reusable file. If the program you are debugging is
4505 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4506 Future GDB debugging sessions will notice the presence of this file,
4507 and will quickly map in symbol information from it, rather than reading
4508 the symbol table from the executable program. Using the '-mapped'
4509 option in a GDB `file' or `symbol-file' command has the same effect as
4510 starting GDB with the '-mapped' command-line option.
4512 You can cause GDB to read the entire symbol table immediately by using
4513 the '-readnow' option with any of the commands that load symbol table
4514 information (or on the GDB command line). This makes the command
4515 slower, but makes future operations faster.
4517 The -mapped and -readnow options are typically combined in order to
4518 build a `fred.syms' file that contains complete symbol information.
4519 A simple GDB invocation to do nothing but build a `.syms' file for future
4522 gdb -batch -nx -mapped -readnow programname
4524 The `.syms' file is specific to the host machine on which GDB is run.
4525 It holds an exact image of GDB's internal symbol table. It cannot be
4526 shared across multiple host platforms.
4528 * longjmp() handling
4530 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4531 siglongjmp() without losing control. This feature has not yet been ported to
4532 all systems. It currently works on many 386 platforms, all MIPS-based
4533 platforms (SGI, DECstation, etc), and Sun3/4.
4537 Preliminary work has been put in to support the new Solaris OS from Sun. At
4538 this time, it can control and debug processes, but it is not capable of
4543 As always, many many bug fixes. The major areas were with g++, and mipsread.
4544 People using the MIPS-based platforms should experience fewer mysterious
4545 crashes and trashed symbol tables.
4547 *** Changes in GDB-4.4:
4549 * New machines supported (host and target)
4551 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4553 BSD Reno on Vax vax-dec-bsd
4554 Ultrix on Vax vax-dec-ultrix
4556 * New machines supported (target)
4558 AMD 29000 embedded, using EBMON a29k-none-none
4562 GDB continues to improve its handling of C++. `References' work better.
4563 The demangler has also been improved, and now deals with symbols mangled as
4564 per the Annotated C++ Reference Guide.
4566 GDB also now handles `stabs' symbol information embedded in MIPS
4567 `ecoff' symbol tables. Since the ecoff format was not easily
4568 extensible to handle new languages such as C++, this appeared to be a
4569 good way to put C++ debugging info into MIPS binaries. This option
4570 will be supported in the GNU C compiler, version 2, when it is
4573 * New features for SVR4
4575 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4576 shared libraries. Debugging dynamically linked programs should present
4577 only minor differences from debugging statically linked programs.
4579 The `info proc' command will print out information about any process
4580 on an SVR4 system (including the one you are debugging). At the moment,
4581 it prints the address mappings of the process.
4583 If you bring up GDB on another SVR4 system, please send mail to
4584 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4586 * Better dynamic linking support in SunOS
4588 Reading symbols from shared libraries which contain debugging symbols
4589 now works properly. However, there remain issues such as automatic
4590 skipping of `transfer vector' code during function calls, which
4591 make it harder to debug code in a shared library, than to debug the
4592 same code linked statically.
4596 GDB is now using the latest `getopt' routines from the FSF. This
4597 version accepts the -- prefix for options with long names. GDB will
4598 continue to accept the old forms (-option and +option) as well.
4599 Various single letter abbreviations for options have been explicity
4600 added to the option table so that they won't get overshadowed in the
4601 future by other options that begin with the same letter.
4605 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4606 Many assorted bugs have been handled. Many more remain to be handled.
4607 See the various ChangeLog files (primarily in gdb and bfd) for details.
4610 *** Changes in GDB-4.3:
4612 * New machines supported (host and target)
4614 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4615 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4616 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4618 * Almost SCO Unix support
4620 We had hoped to support:
4621 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4622 (except for core file support), but we discovered very late in the release
4623 that it has problems with process groups that render gdb unusable. Sorry
4624 about that. I encourage people to fix it and post the fixes.
4626 * Preliminary ELF and DWARF support
4628 GDB can read ELF object files on System V Release 4, and can handle
4629 debugging records for C, in DWARF format, in ELF files. This support
4630 is preliminary. If you bring up GDB on another SVR4 system, please
4631 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4636 GDB now uses the latest `readline' library. One user-visible change
4637 is that two tabs will list possible command completions, which previously
4638 required typing M-? (meta-question mark, or ESC ?).
4642 The `stepi' bug that many of you noticed has been squashed.
4643 Many bugs in C++ have been handled. Many more remain to be handled.
4644 See the various ChangeLog files (primarily in gdb and bfd) for details.
4646 * State of the MIPS world (in case you wondered):
4648 GDB can understand the symbol tables emitted by the compilers
4649 supplied by most vendors of MIPS-based machines, including DEC. These
4650 symbol tables are in a format that essentially nobody else uses.
4652 Some versions of gcc come with an assembler post-processor called
4653 mips-tfile. This program is required if you want to do source-level
4654 debugging of gcc-compiled programs. I believe FSF does not ship
4655 mips-tfile with gcc version 1, but it will eventually come with gcc
4658 Debugging of g++ output remains a problem. g++ version 1.xx does not
4659 really support it at all. (If you're lucky, you should be able to get
4660 line numbers and stack traces to work, but no parameters or local
4661 variables.) With some work it should be possible to improve the
4664 When gcc version 2 is released, you will have somewhat better luck.
4665 However, even then you will get confusing results for inheritance and
4668 We will eventually provide full debugging of g++ output on
4669 DECstations. This will probably involve some kind of stabs-in-ecoff
4670 encapulation, but the details have not been worked out yet.
4673 *** Changes in GDB-4.2:
4675 * Improved configuration
4677 Only one copy of `configure' exists now, and it is not self-modifying.
4678 Porting BFD is simpler.
4682 The `step' and `next' commands now only stop at the first instruction
4683 of a source line. This prevents the multiple stops that used to occur
4684 in switch statements, for-loops, etc. `Step' continues to stop if a
4685 function that has debugging information is called within the line.
4689 Lots of small bugs fixed. More remain.
4691 * New host supported (not target)
4693 Intel 386 PC clone running Mach i386-none-mach
4696 *** Changes in GDB-4.1:
4698 * Multiple source language support
4700 GDB now has internal scaffolding to handle several source languages.
4701 It determines the type of each source file from its filename extension,
4702 and will switch expression parsing and number formatting to match the
4703 language of the function in the currently selected stack frame.
4704 You can also specifically set the language to be used, with
4705 `set language c' or `set language modula-2'.
4709 GDB now has preliminary support for the GNU Modula-2 compiler,
4710 currently under development at the State University of New York at
4711 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4712 continue through the fall of 1991 and into 1992.
4714 Other Modula-2 compilers are currently not supported, and attempting to
4715 debug programs compiled with them will likely result in an error as the
4716 symbol table is read. Feel free to work on it, though!
4718 There are hooks in GDB for strict type checking and range checking,
4719 in the `Modula-2 philosophy', but they do not currently work.
4723 GDB can now write to executable and core files (e.g. patch
4724 a variable's value). You must turn this switch on, specify
4725 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4726 by assigning a new value to a variable. Modifications take
4729 * Automatic SunOS shared library reading
4731 When you run your program, GDB automatically determines where its
4732 shared libraries (if any) have been loaded, and reads their symbols.
4733 The `share' command is no longer needed. This also works when
4734 examining core files.
4738 You can specify the number of lines that the `list' command shows.
4741 * New machines supported (host and target)
4743 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4744 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4745 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4747 * New hosts supported (not targets)
4749 IBM RT/PC: romp-ibm-aix or rtpc
4751 * New targets supported (not hosts)
4753 AMD 29000 embedded with COFF a29k-none-coff
4754 AMD 29000 embedded with a.out a29k-none-aout
4755 Ultracomputer remote kernel debug a29k-nyu-kern
4757 * New remote interfaces
4763 *** Changes in GDB-4.0:
4767 Wide output is wrapped at good places to make the output more readable.
4769 Gdb now supports cross-debugging from a host machine of one type to a
4770 target machine of another type. Communication with the target system
4771 is over serial lines. The ``target'' command handles connecting to the
4772 remote system; the ``load'' command will download a program into the
4773 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4774 also supports debugging of realtime processes running under VxWorks,
4775 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4776 stub on the target system.
4778 New CPUs supported include the AMD 29000 and Intel 960.
4780 GDB now reads object files and symbol tables via a ``binary file''
4781 library, which allows a single copy of GDB to debug programs of multiple
4782 object file types such as a.out and coff.
4784 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4785 refcard.dvi and refcard.ps are available to format it).
4788 * Control-Variable user interface simplified
4790 All variables that control the operation of the debugger can be set
4791 by the ``set'' command, and displayed by the ``show'' command.
4793 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4794 ``Show prompt'' produces the response:
4795 Gdb's prompt is new-gdb=>.
4797 What follows are the NEW set commands. The command ``help set'' will
4798 print a complete list of old and new set commands. ``help set FOO''
4799 will give a longer description of the variable FOO. ``show'' will show
4800 all of the variable descriptions and their current settings.
4802 confirm on/off: Enables warning questions for operations that are
4803 hard to recover from, e.g. rerunning the program while
4804 it is already running. Default is ON.
4806 editing on/off: Enables EMACS style command line editing
4807 of input. Previous lines can be recalled with
4808 control-P, the current line can be edited with control-B,
4809 you can search for commands with control-R, etc.
4812 history filename NAME: NAME is where the gdb command history
4813 will be stored. The default is .gdb_history,
4814 or the value of the environment variable
4817 history size N: The size, in commands, of the command history. The
4818 default is 256, or the value of the environment variable
4821 history save on/off: If this value is set to ON, the history file will
4822 be saved after exiting gdb. If set to OFF, the
4823 file will not be saved. The default is OFF.
4825 history expansion on/off: If this value is set to ON, then csh-like
4826 history expansion will be performed on
4827 command line input. The default is OFF.
4829 radix N: Sets the default radix for input and output. It can be set
4830 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4831 in the current radix, so "set radix 10" is always a no-op.
4833 height N: This integer value is the number of lines on a page. Default
4834 is 24, the current `stty rows'' setting, or the ``li#''
4835 setting from the termcap entry matching the environment
4838 width N: This integer value is the number of characters on a line.
4839 Default is 80, the current `stty cols'' setting, or the ``co#''
4840 setting from the termcap entry matching the environment
4843 Note: ``set screensize'' is obsolete. Use ``set height'' and
4844 ``set width'' instead.
4846 print address on/off: Print memory addresses in various command displays,
4847 such as stack traces and structure values. Gdb looks
4848 more ``symbolic'' if you turn this off; it looks more
4849 ``machine level'' with it on. Default is ON.
4851 print array on/off: Prettyprint arrays. New convenient format! Default
4854 print demangle on/off: Print C++ symbols in "source" form if on,
4857 print asm-demangle on/off: Same, for assembler level printouts
4860 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4863 * Support for Epoch Environment.
4865 The epoch environment is a version of Emacs v18 with windowing. One
4866 new command, ``inspect'', is identical to ``print'', except that if you
4867 are running in the epoch environment, the value is printed in its own
4871 * Support for Shared Libraries
4873 GDB can now debug programs and core files that use SunOS shared libraries.
4874 Symbols from a shared library cannot be referenced
4875 before the shared library has been linked with the program (this
4876 happens after you type ``run'' and before the function main() is entered).
4877 At any time after this linking (including when examining core files
4878 from dynamically linked programs), gdb reads the symbols from each
4879 shared library when you type the ``sharedlibrary'' command.
4880 It can be abbreviated ``share''.
4882 sharedlibrary REGEXP: Load shared object library symbols for files
4883 matching a unix regular expression. No argument
4884 indicates to load symbols for all shared libraries.
4886 info sharedlibrary: Status of loaded shared libraries.
4891 A watchpoint stops execution of a program whenever the value of an
4892 expression changes. Checking for this slows down execution
4893 tremendously whenever you are in the scope of the expression, but is
4894 quite useful for catching tough ``bit-spreader'' or pointer misuse
4895 problems. Some machines such as the 386 have hardware for doing this
4896 more quickly, and future versions of gdb will use this hardware.
4898 watch EXP: Set a watchpoint (breakpoint) for an expression.
4900 info watchpoints: Information about your watchpoints.
4902 delete N: Deletes watchpoint number N (same as breakpoints).
4903 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4904 enable N: Re-enables watchpoint number N (same as breakpoints).
4907 * C++ multiple inheritance
4909 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4912 * C++ exception handling
4914 Gdb now supports limited C++ exception handling. Besides the existing
4915 ability to breakpoint on an exception handler, gdb can breakpoint on
4916 the raising of an exception (before the stack is peeled back to the
4919 catch FOO: If there is a FOO exception handler in the dynamic scope,
4920 set a breakpoint to catch exceptions which may be raised there.
4921 Multiple exceptions (``catch foo bar baz'') may be caught.
4923 info catch: Lists all exceptions which may be caught in the
4924 current stack frame.
4927 * Minor command changes
4929 The command ``call func (arg, arg, ...)'' now acts like the print
4930 command, except it does not print or save a value if the function's result
4931 is void. This is similar to dbx usage.
4933 The ``up'' and ``down'' commands now always print the frame they end up
4934 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4935 frames without printing.
4937 * New directory command
4939 'dir' now adds directories to the FRONT of the source search path.
4940 The path starts off empty. Source files that contain debug information
4941 about the directory in which they were compiled can be found even
4942 with an empty path; Sun CC and GCC include this information. If GDB can't
4943 find your source file in the current directory, type "dir .".
4945 * Configuring GDB for compilation
4947 For normal use, type ``./configure host''. See README or gdb.texinfo
4950 GDB now handles cross debugging. If you are remotely debugging between
4951 two different machines, type ``./configure host -target=targ''.
4952 Host is the machine where GDB will run; targ is the machine
4953 where the program that you are debugging will run.