1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.2
6 * GDB has a new command: "thread find [REGEXP]".
7 It finds the thread id whose name, target id, or thread extra info
8 matches the given regular expression.
10 * The "catch syscall" command now works on mips*-linux* targets.
12 * The -data-disassemble MI command now supports modes 2 and 3 for
13 dumping the instruction opcodes.
15 * New command line options
17 -data-directory DIR Specify DIR as the "data-directory".
18 This is mostly for testing purposes.
20 * The "maint set python auto-load on|off" command has been renamed to
21 "set auto-load-scripts on|off".
23 * GDB has a new command: "set directories".
24 It is like the "dir" command except that it replaces the
25 source path list instead of augmenting it.
27 * GDB now understands thread names.
29 On GNU/Linux, "info threads" will display the thread name as set by
30 prctl or pthread_setname_np.
32 There is also a new command, "thread name", which can be used to
33 assign a name internally for GDB to display.
36 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
37 has been integrated into GDB.
41 ** The function gdb.Write now accepts an optional keyword 'stream'.
42 This keyword, when provided, will direct the output to either
43 stdout, stderr, or GDB's logging output.
45 ** Parameters can now be be sub-classed in Python, and in particular
46 you may implement the get_set_doc and get_show_doc functions.
47 This improves how Parameter set/show documentation is processed
48 and allows for more dynamic content.
50 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
51 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
52 have an is_valid method.
54 ** Breakpoints can now be sub-classed in Python, and in particular
55 you may implement a 'stop' function that is executed each time
56 the inferior reaches that breakpoint.
58 ** New function gdb.lookup_global_symbol looks up a global symbol.
60 ** GDB values in Python are now callable if the value represents a
61 function. For example, if 'some_value' represents a function that
62 takes two integer parameters and returns a value, you can call
63 that function like so:
65 result = some_value (10,20)
67 ** Module gdb.types has been added.
68 It contains a collection of utilities for working with gdb.Types objects:
69 get_basic_type, has_field, make_enum_dict.
71 ** Module gdb.printing has been added.
72 It contains utilities for writing and registering pretty-printers.
73 New classes: PrettyPrinter, SubPrettyPrinter,
74 RegexpCollectionPrettyPrinter.
75 New function: register_pretty_printer.
77 ** New commands "info pretty-printers", "enable pretty-printer" and
78 "disable pretty-printer" have been added.
80 ** gdb.parameter("directories") is now available.
82 ** New function gdb.newest_frame returns the newest frame in the
85 ** The gdb.InferiorThread class has a new "name" attribute. This
86 holds the thread's name.
88 ** Python Support for Inferior events.
89 Python scripts can add observers to be notified of events
90 occurring in the process being debugged.
91 The following events are currently supported:
92 - gdb.events.cont Continue event.
93 - gdb.events.exited Inferior exited event.
94 - gdb.events.stop Signal received, and Breakpoint hit events.
98 ** GDB now puts template parameters in scope when debugging in an
99 instantiation. For example, if you have:
101 template<int X> int func (void) { return X; }
103 then if you step into func<5>, "print X" will show "5". This
104 feature requires proper debuginfo support from the compiler; it
105 was added to GCC 4.5.
107 ** The motion commands "next", "finish", "until", and "advance" now
108 work better when exceptions are thrown. In particular, GDB will
109 no longer lose control of the inferior; instead, the GDB will
110 stop the inferior at the point at which the exception is caught.
111 This functionality requires a change in the exception handling
112 code that was introduced in GCC 4.5.
114 * GDB now follows GCC's rules on accessing volatile objects when
115 reading or writing target state during expression evaluation.
116 One notable difference to prior behavior is that "print x = 0"
117 no longer generates a read of x; the value of the assignment is
118 now always taken directly from the value being assigned.
120 * GDB now has some support for using labels in the program's source in
121 linespecs. For instance, you can use "advance label" to continue
122 execution to a label.
124 * GDB now has support for reading and writing a new .gdb_index
125 section. This section holds a fast index of DWARF debugging
126 information and can be used to greatly speed up GDB startup and
127 operation. See the documentation for `save gdb-index' for details.
129 * The "watch" command now accepts an optional "-location" argument.
130 When used, this causes GDB to watch the memory referred to by the
131 expression. Such a watchpoint is never deleted due to it going out
134 * GDB now supports thread debugging of core dumps on GNU/Linux.
136 GDB now activates thread debugging using the libthread_db library
137 when debugging GNU/Linux core dumps, similarly to when debugging
138 live processes. As a result, when debugging a core dump file, GDB
139 is now able to display pthread_t ids of threads. For example, "info
140 threads" shows the same output as when debugging the process when it
141 was live. In earlier releases, you'd see something like this:
144 * 1 LWP 6780 main () at main.c:10
146 While now you see this:
149 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
151 It is also now possible to inspect TLS variables when debugging core
154 When debugging a core dump generated on a machine other than the one
155 used to run GDB, you may need to point GDB at the correct
156 libthread_db library with the "set libthread-db-search-path"
157 command. See the user manual for more details on this command.
159 * New features in the GDB remote stub, GDBserver
161 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
162 and i686 LynxOS (version 5.x).
164 ** GDBserver is now supported on Blackfin Linux.
166 * New native configurations
168 ia64 HP-UX ia64-*-hpux*
172 Analog Devices, Inc. Blackfin Processor bfin-*
174 * Ada task switching is now supported on sparc-elf targets when
175 debugging a program using the Ravenscar Profile. For more information,
176 see the "Tasking Support when using the Ravenscar Profile" section
177 in the GDB user manual.
179 * Guile support was removed.
181 * New features in the GNU simulator
183 ** The --map-info flag lists all known core mappings.
185 *** Changes in GDB 7.2
187 * Shared library support for remote targets by default
189 When GDB is configured for a generic, non-OS specific target, like
190 for example, --target=arm-eabi or one of the many *-*-elf targets,
191 GDB now queries remote stubs for loaded shared libraries using the
192 `qXfer:libraries:read' packet. Previously, shared library support
193 was always disabled for such configurations.
197 ** Argument Dependent Lookup (ADL)
199 In C++ ADL lookup directs function search to the namespaces of its
200 arguments even if the namespace has not been imported.
210 Here the compiler will search for `foo' in the namespace of 'b'
211 and find A::foo. GDB now supports this. This construct is commonly
212 used in the Standard Template Library for operators.
214 ** Improved User Defined Operator Support
216 In addition to member operators, GDB now supports lookup of operators
217 defined in a namespace and imported with a `using' directive, operators
218 defined in the global scope, operators imported implicitly from an
219 anonymous namespace, and the ADL operators mentioned in the previous
221 GDB now also supports proper overload resolution for all the previously
222 mentioned flavors of operators.
224 ** static const class members
226 Printing of static const class members that are initialized in the
227 class definition has been fixed.
229 * Windows Thread Information Block access.
231 On Windows targets, GDB now supports displaying the Windows Thread
232 Information Block (TIB) structure. This structure is visible either
233 by using the new command `info w32 thread-information-block' or, by
234 dereferencing the new convenience variable named `$_tlb', a
235 thread-specific pointer to the TIB. This feature is also supported
236 when remote debugging using GDBserver.
240 Static tracepoints are calls in the user program into a tracing
241 library. One such library is a port of the LTTng kernel tracer to
242 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
243 When debugging with GDBserver, GDB now supports combining the GDB
244 tracepoint machinery with such libraries. For example: the user can
245 use GDB to probe a static tracepoint marker (a call from the user
246 program into the tracing library) with the new "strace" command (see
247 "New commands" below). This creates a "static tracepoint" in the
248 breakpoint list, that can be manipulated with the same feature set
249 as fast and regular tracepoints. E.g., collect registers, local and
250 global variables, collect trace state variables, and define
251 tracepoint conditions. In addition, the user can collect extra
252 static tracepoint marker specific data, by collecting the new
253 $_sdata internal variable. When analyzing the trace buffer, you can
254 inspect $_sdata like any other variable available to GDB. For more
255 information, see the "Tracepoints" chapter in GDB user manual. New
256 remote packets have been defined to support static tracepoints, see
257 the "New remote packets" section below.
259 * Better reconstruction of tracepoints after disconnected tracing
261 GDB will attempt to download the original source form of tracepoint
262 definitions when starting a trace run, and then will upload these
263 upon reconnection to the target, resulting in a more accurate
264 reconstruction of the tracepoints that are in use on the target.
268 You can now exercise direct control over the ways that GDB can
269 affect your program. For instance, you can disallow the setting of
270 breakpoints, so that the program can run continuously (assuming
271 non-stop mode). In addition, the "observer" variable is available
272 to switch all of the different controls; in observer mode, GDB
273 cannot affect the target's behavior at all, which is useful for
274 tasks like diagnosing live systems in the field.
276 * The new convenience variable $_thread holds the number of the
283 Return the address of the Windows Thread Information Block of a given thread.
287 In response to several of the tracepoint packets, the target may now
288 also respond with a number of intermediate `qRelocInsn' request
289 packets before the final result packet, to have GDB handle
290 relocating an instruction to execute at a different address. This
291 is particularly useful for stubs that support fast tracepoints. GDB
292 reports support for this feature in the qSupported packet.
296 List static tracepoint markers in the target program.
300 List static tracepoint markers at a given address in the target
303 qXfer:statictrace:read
305 Read the static trace data collected (by a `collect $_sdata'
306 tracepoint action). The remote stub reports support for this packet
307 to gdb's qSupported query.
311 Send the current settings of GDB's permission flags.
315 Send part of the source (textual) form of a tracepoint definition,
316 which includes location, conditional, and action list.
318 * The source command now accepts a -s option to force searching for the
319 script in the source search path even if the script name specifies
322 * New features in the GDB remote stub, GDBserver
324 - GDBserver now support tracepoints (including fast tracepoints, and
325 static tracepoints). The feature is currently supported by the
326 i386-linux and amd64-linux builds. See the "Tracepoints support
327 in gdbserver" section in the manual for more information.
329 GDBserver JIT compiles the tracepoint's conditional agent
330 expression bytecode into native code whenever possible for low
331 overhead dynamic tracepoints conditionals. For such tracepoints,
332 an expression that examines program state is evaluated when the
333 tracepoint is reached, in order to determine whether to capture
334 trace data. If the condition is simple and false, processing the
335 tracepoint finishes very quickly and no data is gathered.
337 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
338 for static tracepoints support.
340 - GDBserver now supports x86_64 Windows 64-bit debugging.
342 * GDB now sends xmlRegisters= in qSupported packet to indicate that
343 it understands register description.
345 * The --batch flag now disables pagination and queries.
347 * X86 general purpose registers
349 GDB now supports reading/writing byte, word and double-word x86
350 general purpose registers directly. This means you can use, say,
351 $ah or $ax to refer, respectively, to the byte register AH and
352 16-bit word register AX that are actually portions of the 32-bit
353 register EAX or 64-bit register RAX.
355 * The `commands' command now accepts a range of breakpoints to modify.
356 A plain `commands' following a command that creates multiple
357 breakpoints affects all the breakpoints set by that command. This
358 applies to breakpoints set by `rbreak', and also applies when a
359 single `break' command creates multiple breakpoints (e.g.,
360 breakpoints on overloaded c++ functions).
362 * The `rbreak' command now accepts a filename specification as part of
363 its argument, limiting the functions selected by the regex to those
364 in the specified file.
366 * Support for remote debugging Windows and SymbianOS shared libraries
367 from Unix hosts has been improved. Non Windows GDB builds now can
368 understand target reported file names that follow MS-DOS based file
369 system semantics, such as file names that include drive letters and
370 use the backslash character as directory separator. This makes it
371 possible to transparently use the "set sysroot" and "set
372 solib-search-path" on Unix hosts to point as host copies of the
373 target's shared libraries. See the new command "set
374 target-file-system-kind" described below, and the "Commands to
375 specify files" section in the user manual for more information.
379 eval template, expressions...
380 Convert the values of one or more expressions under the control
381 of the string template to a command line, and call it.
383 set target-file-system-kind unix|dos-based|auto
384 show target-file-system-kind
385 Set or show the assumed file system kind for target reported file
388 save breakpoints <filename>
389 Save all current breakpoint definitions to a file suitable for use
390 in a later debugging session. To read the saved breakpoint
391 definitions, use the `source' command.
393 `save tracepoints' is a new alias for `save-tracepoints'. The latter
396 info static-tracepoint-markers
397 Display information about static tracepoint markers in the target.
399 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
400 Define a static tracepoint by probing a marker at the given
401 function, line, address, or marker ID.
405 Enable and disable observer mode.
407 set may-write-registers on|off
408 set may-write-memory on|off
409 set may-insert-breakpoints on|off
410 set may-insert-tracepoints on|off
411 set may-insert-fast-tracepoints on|off
412 set may-interrupt on|off
413 Set individual permissions for GDB effects on the target. Note that
414 some of these settings can have undesirable or surprising
415 consequences, particularly when changed in the middle of a session.
416 For instance, disabling the writing of memory can prevent
417 breakpoints from being inserted, cause single-stepping to fail, or
418 even crash your program, if you disable after breakpoints have been
419 inserted. However, GDB should not crash.
421 set record memory-query on|off
422 show record memory-query
423 Control whether to stop the inferior if memory changes caused
424 by an instruction cannot be recorded.
429 The disassemble command now supports "start,+length" form of two arguments.
433 ** GDB now provides a new directory location, called the python directory,
434 where Python scripts written for GDB can be installed. The location
435 of that directory is <data-directory>/python, where <data-directory>
436 is the GDB data directory. For more details, see section `Scripting
437 GDB using Python' in the manual.
439 ** The GDB Python API now has access to breakpoints, symbols, symbol
440 tables, program spaces, inferiors, threads and frame's code blocks.
441 Additionally, GDB Parameters can now be created from the API, and
442 manipulated via set/show in the CLI.
444 ** New functions gdb.target_charset, gdb.target_wide_charset,
445 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
447 ** New exception gdb.GdbError.
449 ** Pretty-printers are now also looked up in the current program space.
451 ** Pretty-printers can now be individually enabled and disabled.
453 ** GDB now looks for names of Python scripts to auto-load in a
454 special section named `.debug_gdb_scripts', in addition to looking
455 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
457 * Tracepoint actions were unified with breakpoint commands. In particular,
458 there are no longer differences in "info break" output for breakpoints and
459 tracepoints and the "commands" command can be used for both tracepoints and
464 ARM Symbian arm*-*-symbianelf*
466 * D language support.
467 GDB now supports debugging programs written in the D programming
470 * GDB now supports the extended ptrace interface for PowerPC which is
471 available since Linux kernel version 2.6.34. This automatically enables
472 any hardware breakpoints and additional hardware watchpoints available in
473 the processor. The old ptrace interface exposes just one hardware
474 watchpoint and no hardware breakpoints.
476 * GDB is now able to use the Data Value Compare (DVC) register available on
477 embedded PowerPC processors to implement in hardware simple watchpoint
478 conditions of the form:
480 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
482 This works in native GDB running on Linux kernels with the extended ptrace
483 interface mentioned above.
485 *** Changes in GDB 7.1
491 GDB now supports importing of namespaces in C++. This enables the
492 user to inspect variables from imported namespaces. Support for
493 namepace aliasing has also been added. So, if a namespace is
494 aliased in the current scope (e.g. namepace C=A; ) the user can
495 print variables using the alias (e.g. (gdb) print C::x).
499 All known bugs relating to the printing of virtual base class were
500 fixed. It is now possible to call overloaded static methods using a
505 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
506 and reinterpret_cast<> are now handled by the C++ expression parser.
510 Xilinx MicroBlaze microblaze-*-*
515 Xilinx MicroBlaze microblaze
518 * Multi-program debugging.
520 GDB now has support for multi-program (a.k.a. multi-executable or
521 multi-exec) debugging. This allows for debugging multiple inferiors
522 simultaneously each running a different program under the same GDB
523 session. See "Debugging Multiple Inferiors and Programs" in the
524 manual for more information. This implied some user visible changes
525 in the multi-inferior support. For example, "info inferiors" now
526 lists inferiors that are not running yet or that have exited
527 already. See also "New commands" and "New options" below.
529 * New tracing features
531 GDB's tracepoint facility now includes several new features:
533 ** Trace state variables
535 GDB tracepoints now include support for trace state variables, which
536 are variables managed by the target agent during a tracing
537 experiment. They are useful for tracepoints that trigger each
538 other, so for instance one tracepoint can count hits in a variable,
539 and then a second tracepoint has a condition that is true when the
540 count reaches a particular value. Trace state variables share the
541 $-syntax of GDB convenience variables, and can appear in both
542 tracepoint actions and condition expressions. Use the "tvariable"
543 command to create, and "info tvariables" to view; see "Trace State
544 Variables" in the manual for more detail.
548 GDB now includes an option for defining fast tracepoints, which
549 targets may implement more efficiently, such as by installing a jump
550 into the target agent rather than a trap instruction. The resulting
551 speedup can be by two orders of magnitude or more, although the
552 tradeoff is that some program locations on some target architectures
553 might not allow fast tracepoint installation, for instance if the
554 instruction to be replaced is shorter than the jump. To request a
555 fast tracepoint, use the "ftrace" command, with syntax identical to
556 the regular trace command.
558 ** Disconnected tracing
560 It is now possible to detach GDB from the target while it is running
561 a trace experiment, then reconnect later to see how the experiment
562 is going. In addition, a new variable disconnected-tracing lets you
563 tell the target agent whether to continue running a trace if the
564 connection is lost unexpectedly.
568 GDB now has the ability to save the trace buffer into a file, and
569 then use that file as a target, similarly to you can do with
570 corefiles. You can select trace frames, print data that was
571 collected in them, and use tstatus to display the state of the
572 tracing run at the moment that it was saved. To create a trace
573 file, use "tsave <filename>", and to use it, do "target tfile
576 ** Circular trace buffer
578 You can ask the target agent to handle the trace buffer as a
579 circular buffer, discarding the oldest trace frames to make room for
580 newer ones, by setting circular-trace-buffer to on. This feature may
581 not be available for all target agents.
586 The disassemble command, when invoked with two arguments, now requires
587 the arguments to be comma-separated.
590 The info variables command now displays variable definitions. Files
591 which only declare a variable are not shown.
594 The source command is now capable of sourcing Python scripts.
595 This feature is dependent on the debugger being build with Python
598 Related to this enhancement is also the introduction of a new command
599 "set script-extension" (see below).
601 * New commands (for set/show, see "New options" below)
603 record save [<FILENAME>]
604 Save a file (in core file format) containing the process record
605 execution log for replay debugging at a later time.
607 record restore <FILENAME>
608 Restore the process record execution log that was saved at an
609 earlier time, for replay debugging.
611 add-inferior [-copies <N>] [-exec <FILENAME>]
614 clone-inferior [-copies <N>] [ID]
615 Make a new inferior ready to execute the same program another
621 maint info program-spaces
622 List the program spaces loaded into GDB.
624 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
625 show remote interrupt-sequence
626 Allow the user to select one of ^C, a BREAK signal or BREAK-g
627 as the sequence to the remote target in order to interrupt the execution.
628 Ctrl-C is a default. Some system prefers BREAK which is high level of
629 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
630 Magic SysRq g. It is BREAK signal and character 'g'.
632 set remote interrupt-on-connect [on | off]
633 show remote interrupt-on-connect
634 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
635 remote target when gdb connects to it. This is needed when you debug
638 set remotebreak [on | off]
640 Deprecated. Use "set/show remote interrupt-sequence" instead.
642 tvariable $NAME [ = EXP ]
643 Create or modify a trace state variable.
646 List trace state variables and their values.
648 delete tvariable $NAME ...
649 Delete one or more trace state variables.
652 Evaluate the given expressions without collecting anything into the
653 trace buffer. (Valid in tracepoint actions only.)
655 ftrace FN / FILE:LINE / *ADDR
656 Define a fast tracepoint at the given function, line, or address.
658 * New expression syntax
660 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
661 GDB now parses 0b101010 identically with 42.
665 set follow-exec-mode new|same
666 show follow-exec-mode
667 Control whether GDB reuses the same inferior across an exec call or
668 creates a new one. This is useful to be able to restart the old
669 executable after the inferior having done an exec call.
671 set default-collect EXPR, ...
673 Define a list of expressions to be collected at each tracepoint.
674 This is a useful way to ensure essential items are not overlooked,
675 such as registers or a critical global variable.
677 set disconnected-tracing
678 show disconnected-tracing
679 If set to 1, the target is instructed to continue tracing if it
680 loses its connection to GDB. If 0, the target is to stop tracing
683 set circular-trace-buffer
684 show circular-trace-buffer
685 If set to on, the target is instructed to use a circular trace buffer
686 and discard the oldest trace frames instead of stopping the trace due
687 to a full trace buffer. If set to off, the trace stops when the buffer
688 fills up. Some targets may not support this.
690 set script-extension off|soft|strict
691 show script-extension
692 If set to "off", the debugger does not perform any script language
693 recognition, and all sourced files are assumed to be GDB scripts.
694 If set to "soft" (the default), files are sourced according to
695 filename extension, falling back to GDB scripts if the first
697 If set to "strict", files are sourced according to filename extension.
699 set ada trust-PAD-over-XVS on|off
700 show ada trust-PAD-over-XVS
701 If off, activate a workaround against a bug in the debugging information
702 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
703 the GCC sources for more information about the GNAT encoding and
704 PAD types in particular). It is always safe to set this option to
705 off, but this introduces a slight performance penalty. The default
708 * Python API Improvements
710 ** GDB provides the new class gdb.LazyString. This is useful in
711 some pretty-printing cases. The new method gdb.Value.lazy_string
712 provides a simple way to create objects of this type.
714 ** The fields returned by gdb.Type.fields now have an
715 `is_base_class' attribute.
717 ** The new method gdb.Type.range returns the range of an array type.
719 ** The new method gdb.parse_and_eval can be used to parse and
720 evaluate an expression.
725 Define a trace state variable.
728 Get the current value of a trace state variable.
731 Set desired tracing behavior upon disconnection.
734 Set the trace buffer to be linear or circular.
737 Get data about the tracepoints currently in use.
741 Process record now works correctly with hardware watchpoints.
743 Multiple bug fixes have been made to the mips-irix port, making it
744 much more reliable. In particular:
745 - Debugging threaded applications is now possible again. Previously,
746 GDB would hang while starting the program, or while waiting for
747 the program to stop at a breakpoint.
748 - Attaching to a running process no longer hangs.
749 - An error occurring while loading a core file has been fixed.
750 - Changing the value of the PC register now works again. This fixes
751 problems observed when using the "jump" command, or when calling
752 a function from GDB, or even when assigning a new value to $pc.
753 - With the "finish" and "return" commands, the return value for functions
754 returning a small array is now correctly printed.
755 - It is now possible to break on shared library code which gets executed
756 during a shared library init phase (code executed while executing
757 their .init section). Previously, the breakpoint would have no effect.
758 - GDB is now able to backtrace through the signal handler for
759 non-threaded programs.
761 PIE (Position Independent Executable) programs debugging is now supported.
762 This includes debugging execution of PIC (Position Independent Code) shared
763 libraries although for that, it should be possible to run such libraries as an
766 *** Changes in GDB 7.0
768 * GDB now has an interface for JIT compilation. Applications that
769 dynamically generate code can create symbol files in memory and register
770 them with GDB. For users, the feature should work transparently, and
771 for JIT developers, the interface is documented in the GDB manual in the
772 "JIT Compilation Interface" chapter.
774 * Tracepoints may now be conditional. The syntax is as for
775 breakpoints; either an "if" clause appended to the "trace" command,
776 or the "condition" command is available. GDB sends the condition to
777 the target for evaluation using the same bytecode format as is used
778 for tracepoint actions.
780 * The disassemble command now supports: an optional /r modifier, print the
781 raw instructions in hex as well as in symbolic form, and an optional /m
782 modifier to print mixed source+assembly.
784 * Process record and replay
786 In a architecture environment that supports ``process record and
787 replay'', ``process record and replay'' target can record a log of
788 the process execution, and replay it with both forward and reverse
791 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
792 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
793 set execution-direction {forward|reverse}, for targets that support
796 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
797 feature is available with a native GDB running on kernel version
800 * GDB now has support for multi-byte and wide character sets on the
801 target. Strings whose character type is wchar_t, char16_t, or
802 char32_t are now correctly printed. GDB supports wide- and unicode-
803 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
804 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
805 `printf'. This feature requires iconv to work properly; if your
806 system does not have a working iconv, GDB can use GNU libiconv. See
807 the installation instructions for more information.
809 * GDB now supports automatic retrieval of shared library files from
810 remote targets. To use this feature, specify a system root that begins
811 with the `remote:' prefix, either via the `set sysroot' command or via
812 the `--with-sysroot' configure-time option.
814 * "info sharedlibrary" now takes an optional regex of libraries to show,
815 and it now reports if a shared library has no debugging information.
817 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
818 now complete on file names.
820 * When completing in expressions, gdb will attempt to limit
821 completions to allowable structure or union fields, where appropriate.
822 For instance, consider:
824 # struct example { int f1; double f2; };
825 # struct example variable;
828 If the user types TAB at the end of this command line, the available
829 completions will be "f1" and "f2".
831 * Inlined functions are now supported. They show up in backtraces, and
832 the "step", "next", and "finish" commands handle them automatically.
834 * GDB now supports the token-splicing (##) and stringification (#)
835 operators when expanding macros. It also supports variable-arity
838 * GDB now supports inspecting extra signal information, exported by
839 the new $_siginfo convenience variable. The feature is currently
840 implemented on linux ARM, i386 and amd64.
842 * GDB can now display the VFP floating point registers and NEON vector
843 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
844 can provide these registers (requires Linux 2.6.30 or later). Remote
845 and simulator targets may also provide them.
850 Search memory for a sequence of bytes.
853 Turn off `+'/`-' protocol acknowledgments to permit more efficient
854 operation over reliable transport links. Use of this packet is
855 controlled by the `set remote noack-packet' command.
858 Kill the process with the specified process ID. Use this in preference
859 to `k' when multiprocess protocol extensions are supported.
862 Obtains additional operating system information
866 Read or write additional signal information.
868 * Removed remote protocol undocumented extension
870 An undocumented extension to the remote protocol's `S' stop reply
871 packet that permited the stub to pass a process id was removed.
872 Remote servers should use the `T' stop reply packet instead.
874 * GDB now supports multiple function calling conventions according to the
875 DWARF-2 DW_AT_calling_convention function attribute.
877 * The SH target utilizes the aforementioned change to distinguish between gcc
878 and Renesas calling convention. It also adds the new CLI commands
879 `set/show sh calling-convention'.
881 * GDB can now read compressed debug sections, as produced by GNU gold
882 with the --compress-debug-sections=zlib flag.
884 * 64-bit core files are now supported on AIX.
886 * Thread switching is now supported on Tru64.
888 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
889 which will be allocated using malloc later in program execution.
891 * The qXfer:libraries:read remote procotol packet now allows passing a
892 list of section offsets.
894 * On GNU/Linux, GDB can now attach to stopped processes. Several race
895 conditions handling signals delivered during attach or thread creation
896 have also been fixed.
898 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
899 From the user's standpoint, all unqualified instances of True and False
900 are treated as the standard definitions, regardless of context.
902 * GDB now parses C++ symbol and type names more flexibly. For
905 template<typename T> class C { };
908 GDB will now correctly handle all of:
910 ptype C<char const *>
912 ptype C<const char *>
915 * New features in the GDB remote stub, gdbserver
917 - The "--wrapper" command-line argument tells gdbserver to use a
918 wrapper program to launch programs for debugging.
920 - On PowerPC and S/390 targets, it is now possible to use a single
921 gdbserver executable to debug both 32-bit and 64-bit programs.
922 (This requires gdbserver itself to be built as a 64-bit executable.)
924 - gdbserver uses the new noack protocol mode for TCP connections to
925 reduce communications latency, if also supported and enabled in GDB.
927 - Support for the sparc64-linux-gnu target is now included in
930 - The amd64-linux build of gdbserver now supports debugging both
931 32-bit and 64-bit programs.
933 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
934 now support hardware watchpoints, and will use them automatically
939 GDB now has support for scripting using Python. Whether this is
940 available is determined at configure time.
942 New GDB commands can now be written in Python.
944 * Ada tasking support
946 Ada tasks can now be inspected in GDB. The following commands have
950 Print the list of Ada tasks.
952 Print detailed information about task number N.
954 Print the task number of the current task.
956 Switch the context of debugging to task number N.
958 * Support for user-defined prefixed commands. The "define" command can
959 add new commands to existing prefixes, e.g. "target".
961 * Multi-inferior, multi-process debugging.
963 GDB now has generalized support for multi-inferior debugging. See
964 "Debugging Multiple Inferiors" in the manual for more information.
965 Although availability still depends on target support, the command
966 set is more uniform now. The GNU/Linux specific multi-forks support
967 has been migrated to this new framework. This implied some user
968 visible changes; see "New commands" and also "Removed commands"
971 * Target descriptions can now describe the target OS ABI. See the
972 "Target Description Format" section in the user manual for more
975 * Target descriptions can now describe "compatible" architectures
976 to indicate that the target can execute applications for a different
977 architecture in addition to those for the main target architecture.
978 See the "Target Description Format" section in the user manual for
981 * Multi-architecture debugging.
983 GDB now includes general supports for debugging applications on
984 hybrid systems that use more than one single processor architecture
985 at the same time. Each such hybrid architecture still requires
986 specific support to be added. The only hybrid architecture supported
987 in this version of GDB is the Cell Broadband Engine.
989 * GDB now supports integrated debugging of Cell/B.E. applications that
990 use both the PPU and SPU architectures. To enable support for hybrid
991 Cell/B.E. debugging, you need to configure GDB to support both the
992 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
993 --enable-targets configure option.
995 * Non-stop mode debugging.
997 For some targets, GDB now supports an optional mode of operation in
998 which you can examine stopped threads while other threads continue
999 to execute freely. This is referred to as non-stop mode, with the
1000 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1001 section in the user manual for more information.
1003 To be able to support remote non-stop debugging, a remote stub needs
1004 to implement the non-stop mode remote protocol extensions, as
1005 described in the "Remote Non-Stop" section of the user manual. The
1006 GDB remote stub, gdbserver, has been adjusted to support these
1007 extensions on linux targets.
1009 * New commands (for set/show, see "New options" below)
1011 catch syscall [NAME(S) | NUMBER(S)]
1012 Catch system calls. Arguments, which should be names of system
1013 calls or their numbers, mean catch only those syscalls. Without
1014 arguments, every syscall will be caught. When the inferior issues
1015 any of the specified syscalls, GDB will stop and announce the system
1016 call, both when it is called and when its call returns. This
1017 feature is currently available with a native GDB running on the
1018 Linux Kernel, under the following architectures: x86, x86_64,
1019 PowerPC and PowerPC64.
1021 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1023 Search memory for a sequence of bytes.
1025 maint set python print-stack
1026 maint show python print-stack
1027 Show a stack trace when an error is encountered in a Python script.
1030 Invoke CODE by passing it to the Python interpreter.
1035 These allow macros to be defined, undefined, and listed
1039 Show operating system information about processes.
1042 List the inferiors currently under GDB's control.
1045 Switch focus to inferior number NUM.
1048 Detach from inferior number NUM.
1051 Kill inferior number NUM.
1055 set spu stop-on-load
1056 show spu stop-on-load
1057 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1059 set spu auto-flush-cache
1060 show spu auto-flush-cache
1061 Control whether to automatically flush the software-managed cache
1062 during Cell/B.E. debugging.
1064 set sh calling-convention
1065 show sh calling-convention
1066 Control the calling convention used when calling SH target functions.
1069 show debug timestamp
1070 Control display of timestamps with GDB debugging output.
1072 set disassemble-next-line
1073 show disassemble-next-line
1074 Control display of disassembled source lines or instructions when
1077 set remote noack-packet
1078 show remote noack-packet
1079 Set/show the use of remote protocol QStartNoAckMode packet. See above
1080 under "New remote packets."
1082 set remote query-attached-packet
1083 show remote query-attached-packet
1084 Control use of remote protocol `qAttached' (query-attached) packet.
1086 set remote read-siginfo-object
1087 show remote read-siginfo-object
1088 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1091 set remote write-siginfo-object
1092 show remote write-siginfo-object
1093 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1096 set remote reverse-continue
1097 show remote reverse-continue
1098 Control use of remote protocol 'bc' (reverse-continue) packet.
1100 set remote reverse-step
1101 show remote reverse-step
1102 Control use of remote protocol 'bs' (reverse-step) packet.
1104 set displaced-stepping
1105 show displaced-stepping
1106 Control displaced stepping mode. Displaced stepping is a way to
1107 single-step over breakpoints without removing them from the debuggee.
1108 Also known as "out-of-line single-stepping".
1111 show debug displaced
1112 Control display of debugging info for displaced stepping.
1114 maint set internal-error
1115 maint show internal-error
1116 Control what GDB does when an internal error is detected.
1118 maint set internal-warning
1119 maint show internal-warning
1120 Control what GDB does when an internal warning is detected.
1125 Use a wrapper program to launch programs for debugging.
1127 set multiple-symbols (all|ask|cancel)
1128 show multiple-symbols
1129 The value of this variable can be changed to adjust the debugger behavior
1130 when an expression or a breakpoint location contains an ambiguous symbol
1131 name (an overloaded function name, for instance).
1133 set breakpoint always-inserted
1134 show breakpoint always-inserted
1135 Keep breakpoints always inserted in the target, as opposed to inserting
1136 them when resuming the target, and removing them when the target stops.
1137 This option can improve debugger performance on slow remote targets.
1139 set arm fallback-mode (arm|thumb|auto)
1140 show arm fallback-mode
1141 set arm force-mode (arm|thumb|auto)
1143 These commands control how ARM GDB determines whether instructions
1144 are ARM or Thumb. The default for both settings is auto, which uses
1145 the current CPSR value for instructions without symbols; previous
1146 versions of GDB behaved as if "set arm fallback-mode arm".
1148 set disable-randomization
1149 show disable-randomization
1150 Standalone programs run with the virtual address space randomization enabled
1151 by default on some platforms. This option keeps the addresses stable across
1152 multiple debugging sessions.
1156 Control whether other threads are stopped or not when some thread hits
1161 Requests that asynchronous execution is enabled in the target, if available.
1162 In this case, it's possible to resume target in the background, and interact
1163 with GDB while the target is running. "show target-async" displays the
1164 current state of asynchronous execution of the target.
1166 set target-wide-charset
1167 show target-wide-charset
1168 The target-wide-charset is the name of the character set that GDB
1169 uses when printing characters whose type is wchar_t.
1171 set tcp auto-retry (on|off)
1173 set tcp connect-timeout
1174 show tcp connect-timeout
1175 These commands allow GDB to retry failed TCP connections to a remote stub
1176 with a specified timeout period; this is useful if the stub is launched
1177 in parallel with GDB but may not be ready to accept connections immediately.
1179 set libthread-db-search-path
1180 show libthread-db-search-path
1181 Control list of directories which GDB will search for appropriate
1184 set schedule-multiple (on|off)
1185 show schedule-multiple
1186 Allow GDB to resume all threads of all processes or only threads of
1187 the current process.
1191 Use more aggressive caching for accesses to the stack. This improves
1192 performance of remote debugging (particularly backtraces) without
1193 affecting correctness.
1195 set interactive-mode (on|off|auto)
1196 show interactive-mode
1197 Control whether GDB runs in interactive mode (on) or not (off).
1198 When in interactive mode, GDB waits for the user to answer all
1199 queries. Otherwise, GDB does not wait and assumes the default
1200 answer. When set to auto (the default), GDB determines which
1201 mode to use based on the stdin settings.
1206 For program forks, this is replaced by the new more generic `info
1207 inferiors' command. To list checkpoints, you can still use the
1208 `info checkpoints' command, which was an alias for the `info forks'
1212 Replaced by the new `inferior' command. To switch between
1213 checkpoints, you can still use the `restart' command, which was an
1214 alias for the `fork' command.
1217 This is removed, since some targets don't have a notion of
1218 processes. To switch between processes, you can still use the
1219 `inferior' command using GDB's own inferior number.
1222 For program forks, this is replaced by the new more generic `kill
1223 inferior' command. To delete a checkpoint, you can still use the
1224 `delete checkpoint' command, which was an alias for the `delete
1228 For program forks, this is replaced by the new more generic `detach
1229 inferior' command. To detach a checkpoint, you can still use the
1230 `detach checkpoint' command, which was an alias for the `detach
1233 * New native configurations
1235 x86/x86_64 Darwin i[34567]86-*-darwin*
1237 x86_64 MinGW x86_64-*-mingw*
1241 Lattice Mico32 lm32-*
1242 x86 DICOS i[34567]86-*-dicos*
1243 x86_64 DICOS x86_64-*-dicos*
1246 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1247 (mingw32ce) debugging.
1253 These commands were actually not implemented on any target.
1255 *** Changes in GDB 6.8
1257 * New native configurations
1259 NetBSD/hppa hppa*-*netbsd*
1260 Xtensa GNU/Linux xtensa*-*-linux*
1264 NetBSD/hppa hppa*-*-netbsd*
1265 Xtensa GNU/Lunux xtensa*-*-linux*
1267 * Change in command line behavior -- corefiles vs. process ids.
1269 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1270 attaching to process NUMBER fails, GDB no longer attempts to open a
1271 core file named NUMBER. Attaching to a program using the -c option
1272 is no longer supported. Instead, use the '-p' or '--pid' options.
1274 * GDB can now be built as a native debugger for debugging Windows x86
1275 (mingw32) Portable Executable (PE) programs.
1277 * Pending breakpoints no longer change their number when their address
1280 * GDB now supports breakpoints with multiple locations,
1281 including breakpoints on C++ constructors, inside C++ templates,
1282 and in inlined functions.
1284 * GDB's ability to debug optimized code has been improved. GDB more
1285 accurately identifies function bodies and lexical blocks that occupy
1286 more than one contiguous range of addresses.
1288 * Target descriptions can now describe registers for PowerPC.
1290 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1291 registers on PowerPC targets.
1293 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1294 targets even when the libthread_db library is not available.
1296 * The GDB remote stub, gdbserver, now supports the new file transfer
1297 commands (remote put, remote get, and remote delete).
1299 * The GDB remote stub, gdbserver, now supports run and attach in
1300 extended-remote mode.
1302 * hppa*64*-*-hpux11* target broken
1303 The debugger is unable to start a program and fails with the following
1304 error: "Error trying to get information about dynamic linker".
1305 The gdb-6.7 release is also affected.
1307 * GDB now supports the --enable-targets= configure option to allow
1308 building a single GDB executable that supports multiple remote
1309 target architectures.
1311 * GDB now supports debugging C and C++ programs which use the
1312 Decimal Floating Point extension. In addition, the PowerPC target
1313 now has a set of pseudo-registers to inspect decimal float values
1314 stored in two consecutive float registers.
1316 * The -break-insert MI command can optionally create pending
1319 * Improved support for debugging Ada
1320 Many improvements to the Ada language support have been made. These
1322 - Better support for Ada2005 interface types
1323 - Improved handling of arrays and slices in general
1324 - Better support for Taft-amendment types
1325 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1327 - Improved command completion in Ada
1330 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1335 set print frame-arguments (all|scalars|none)
1336 show print frame-arguments
1337 The value of this variable can be changed to control which argument
1338 values should be printed by the debugger when displaying a frame.
1343 Transfer files to and from a remote target, and delete remote files.
1350 Transfer files to and from a remote target, and delete remote files.
1352 * New remote packets
1359 Open, close, read, write, and delete files on the remote system.
1362 Attach to an existing process on the remote system, in extended-remote
1366 Run a new process on the remote system, in extended-remote mode.
1368 *** Changes in GDB 6.7
1370 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1371 bfd, libiberty and opcodes, as revealed by static analysis donated by
1372 Coverity, Inc. (http://scan.coverity.com).
1374 * When looking up multiply-defined global symbols, GDB will now prefer the
1375 symbol definition in the current shared library if it was built using the
1376 -Bsymbolic linker option.
1378 * When the Text User Interface (TUI) is not configured, GDB will now
1379 recognize the -tui command-line option and print a message that the TUI
1382 * The GDB remote stub, gdbserver, now has lower overhead for high
1383 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1385 * GDB for MIPS targets now autodetects whether a remote target provides
1386 32-bit or 64-bit register values.
1388 * Support for C++ member pointers has been improved.
1390 * GDB now understands XML target descriptions, which specify the
1391 target's overall architecture. GDB can read a description from
1392 a local file or over the remote serial protocol.
1394 * Vectors of single-byte data use a new integer type which is not
1395 automatically displayed as character or string data.
1397 * The /s format now works with the print command. It displays
1398 arrays of single-byte integers and pointers to single-byte integers
1401 * Target descriptions can now describe target-specific registers,
1402 for architectures which have implemented the support (currently
1403 only ARM, M68K, and MIPS).
1405 * GDB and the GDB remote stub, gdbserver, now support the XScale
1408 * The GDB remote stub, gdbserver, has been updated to support
1409 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1410 has been rewritten to use the standard GDB remote protocol.
1412 * GDB can now step into C++ functions which are called through thunks.
1414 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1416 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1417 layout. It also supports a TextSeg= and DataSeg= response when only
1418 segment base addresses (rather than offsets) are available.
1420 * The /i format now outputs any trailing branch delay slot instructions
1421 immediately following the last instruction within the count specified.
1423 * The GDB remote protocol "T" stop reply packet now supports a
1424 "library" response. Combined with the new "qXfer:libraries:read"
1425 packet, this response allows GDB to debug shared libraries on targets
1426 where the operating system manages the list of loaded libraries (e.g.
1427 Windows and SymbianOS).
1429 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1430 (DLLs) on Windows and Windows CE targets.
1432 * GDB now supports a faster verification that a .debug file matches its binary
1433 according to its build-id signature, if the signature is present.
1439 Enable or disable hardware flow control (RTS/CTS) on the serial port
1440 when debugging using remote targets.
1442 set mem inaccessible-by-default
1443 show mem inaccessible-by-default
1444 If the target supplies a memory map, for instance via the remote
1445 protocol's "qXfer:memory-map:read" packet, setting this variable
1446 prevents GDB from accessing memory outside the memory map. This
1447 is useful for targets with memory mapped registers or which react
1448 badly to accesses of unmapped address space.
1450 set breakpoint auto-hw
1451 show breakpoint auto-hw
1452 If the target supplies a memory map, for instance via the remote
1453 protocol's "qXfer:memory-map:read" packet, setting this variable
1454 lets GDB use hardware breakpoints automatically for memory regions
1455 where it can not use software breakpoints. This covers both the
1456 "break" command and internal breakpoints used for other commands
1457 including "next" and "finish".
1460 catch exception unhandled
1461 Stop the program execution when Ada exceptions are raised.
1464 Stop the program execution when an Ada assertion failed.
1468 Set an alternate system root for target files. This is a more
1469 general version of "set solib-absolute-prefix", which is now
1470 an alias to "set sysroot".
1473 Provide extended SPU facility status information. This set of
1474 commands is available only when debugging the Cell/B.E. SPU
1477 * New native configurations
1479 OpenBSD/sh sh*-*openbsd*
1482 unset tdesc filename
1484 Use the specified local file as an XML target description, and do
1485 not query the target for its built-in description.
1489 OpenBSD/sh sh*-*-openbsd*
1490 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1491 Toshiba Media Processor mep-elf
1493 * New remote packets
1496 Ignore the specified signals; pass them directly to the debugged program
1497 without stopping other threads or reporting them to GDB.
1499 qXfer:features:read:
1500 Read an XML target description from the target, which describes its
1505 Read or write contents of an spufs file on the target system. These
1506 packets are available only on the Cell/B.E. SPU architecture.
1508 qXfer:libraries:read:
1509 Report the loaded shared libraries. Combined with new "T" packet
1510 response, this packet allows GDB to debug shared libraries on
1511 targets where the operating system manages the list of loaded
1512 libraries (e.g. Windows and SymbianOS).
1516 Support for these obsolete configurations has been removed.
1524 i[34567]86-*-lynxos*
1525 i[34567]86-*-netware*
1526 i[34567]86-*-sco3.2v5*
1527 i[34567]86-*-sco3.2v4*
1529 i[34567]86-*-sysv4.2*
1532 i[34567]86-*-unixware2*
1533 i[34567]86-*-unixware*
1542 * Other removed features
1549 Various m68k-only ROM monitors.
1556 Various Renesas ROM monitors and debugging interfaces for SH and
1561 Support for a Macraigor serial interface to on-chip debugging.
1562 GDB does not directly support the newer parallel or USB
1567 A debug information format. The predecessor to DWARF 2 and
1568 DWARF 3, which are still supported.
1570 Support for the HP aCC compiler on HP-UX/PA-RISC
1572 SOM-encapsulated symbolic debugging information, automatic
1573 invocation of pxdb, and the aCC custom C++ ABI. This does not
1574 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1575 with aCC can still be debugged on an assembly level.
1577 MIPS ".pdr" sections
1579 A MIPS-specific format used to describe stack frame layout
1580 in debugging information.
1584 GDB could work with an older version of Guile to debug
1585 the interpreter and Scheme programs running in it.
1587 set mips stack-arg-size
1588 set mips saved-gpreg-size
1590 Use "set mips abi" to control parameter passing for MIPS.
1592 *** Changes in GDB 6.6
1597 Cell Broadband Engine SPU spu-elf
1599 * GDB can now be configured as a cross-debugger targeting native Windows
1600 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1601 running on a Windows system over TCP/IP to debug Windows programs.
1603 * The GDB remote stub, gdbserver, has been updated to support Windows and
1604 Cygwin debugging. Both single-threaded and multi-threaded programs are
1607 * The "set trust-readonly-sections" command works again. This command was
1608 broken in GDB 6.3, 6.4, and 6.5.
1610 * The "load" command now supports writing to flash memory, if the remote
1611 stub provides the required support.
1613 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1614 longer requires symbolic debug information (e.g. DWARF-2).
1619 unset substitute-path
1620 show substitute-path
1621 Manage a list of substitution rules that GDB uses to rewrite the name
1622 of the directories where the sources are located. This can be useful
1623 for instance when the sources were moved to a different location
1624 between compilation and debugging.
1628 Print each CLI command as it is executed. Each command is prefixed with
1629 a number of `+' symbols representing the nesting depth.
1630 The source command now has a `-v' option to enable the same feature.
1634 The ARM Demon monitor support (RDP protocol, "target rdp").
1636 Kernel Object Display, an embedded debugging feature which only worked with
1637 an obsolete version of Cisco IOS.
1639 The 'set download-write-size' and 'show download-write-size' commands.
1641 * New remote packets
1644 Tell a stub about GDB client features, and request remote target features.
1645 The first feature implemented is PacketSize, which allows the target to
1646 specify the size of packets it can handle - to minimize the number of
1647 packets required and improve performance when connected to a remote
1651 Fetch an OS auxilliary vector from the remote stub. This packet is a
1652 more efficient replacement for qPart:auxv:read.
1654 qXfer:memory-map:read:
1655 Fetch a memory map from the remote stub, including information about
1656 RAM, ROM, and flash memory devices.
1661 Erase and program a flash memory device.
1663 * Removed remote packets
1666 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1667 used it, and only gdbserver implemented it.
1669 *** Changes in GDB 6.5
1673 Renesas M32C/M16C m32c-elf
1675 Morpho Technologies ms1 ms1-elf
1679 init-if-undefined Initialize a convenience variable, but
1680 only if it doesn't already have a value.
1682 The following commands are presently only implemented for native GNU/Linux:
1684 checkpoint Save a snapshot of the program state.
1686 restart <n> Return the program state to a
1687 previously saved state.
1689 info checkpoints List currently saved checkpoints.
1691 delete-checkpoint <n> Delete a previously saved checkpoint.
1693 set|show detach-on-fork Tell gdb whether to detach from a newly
1694 forked process, or to keep debugging it.
1696 info forks List forks of the user program that
1697 are available to be debugged.
1699 fork <n> Switch to debugging one of several
1700 forks of the user program that are
1701 available to be debugged.
1703 delete-fork <n> Delete a fork from the list of forks
1704 that are available to be debugged (and
1705 kill the forked process).
1707 detach-fork <n> Delete a fork from the list of forks
1708 that are available to be debugged (and
1709 allow the process to continue).
1713 Morpho Technologies ms2 ms1-elf
1715 * Improved Windows host support
1717 GDB now builds as a cross debugger hosted on i686-mingw32, including
1718 native console support, and remote communications using either
1719 network sockets or serial ports.
1721 * Improved Modula-2 language support
1723 GDB can now print most types in the Modula-2 syntax. This includes:
1724 basic types, set types, record types, enumerated types, range types,
1725 pointer types and ARRAY types. Procedure var parameters are correctly
1726 printed and hexadecimal addresses and character constants are also
1727 written in the Modula-2 syntax. Best results can be obtained by using
1728 GNU Modula-2 together with the -gdwarf-2 command line option.
1732 The ARM rdi-share module.
1734 The Netware NLM debug server.
1736 *** Changes in GDB 6.4
1738 * New native configurations
1740 OpenBSD/arm arm*-*-openbsd*
1741 OpenBSD/mips64 mips64-*-openbsd*
1745 Morpho Technologies ms1 ms1-elf
1747 * New command line options
1749 --batch-silent As for --batch, but totally silent.
1750 --return-child-result The debugger will exist with the same value
1751 the child (debugged) program exited with.
1752 --eval-command COMMAND, -ex COMMAND
1753 Execute a single GDB CLI command. This may be
1754 specified multiple times and in conjunction
1755 with the --command (-x) option.
1757 * Deprecated commands removed
1759 The following commands, that were deprecated in 2000, have been
1763 set|show arm disassembly-flavor set|show arm disassembler
1764 othernames set arm disassembler
1765 set|show remotedebug set|show debug remote
1766 set|show archdebug set|show debug arch
1767 set|show eventdebug set|show debug event
1770 * New BSD user-level threads support
1772 It is now possible to debug programs using the user-level threads
1773 library on OpenBSD and FreeBSD. Currently supported (target)
1776 FreeBSD/amd64 x86_64-*-freebsd*
1777 FreeBSD/i386 i386-*-freebsd*
1778 OpenBSD/i386 i386-*-openbsd*
1780 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1781 are not yet supported.
1783 * New support for Matsushita MN10300 w/sim added
1784 (Work in progress). mn10300-elf.
1786 * REMOVED configurations and files
1788 VxWorks and the XDR protocol *-*-vxworks
1789 Motorola MCORE mcore-*-*
1790 National Semiconductor NS32000 ns32k-*-*
1792 * New "set print array-indexes" command
1794 After turning this setting "on", GDB prints the index of each element
1795 when displaying arrays. The default is "off" to preserve the previous
1798 * VAX floating point support
1800 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1802 * User-defined command support
1804 In addition to using $arg0..$arg9 for argument passing, it is now possible
1805 to use $argc to determine now many arguments have been passed. See the
1806 section on user-defined commands in the user manual for more information.
1808 *** Changes in GDB 6.3:
1810 * New command line option
1812 GDB now accepts -l followed by a number to set the timeout for remote
1815 * GDB works with GCC -feliminate-dwarf2-dups
1817 GDB now supports a more compact representation of DWARF-2 debug
1818 information using DW_FORM_ref_addr references. These are produced
1819 by GCC with the option -feliminate-dwarf2-dups and also by some
1820 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1821 to use -feliminate-dwarf2-dups.
1823 * Internationalization
1825 When supported by the host system, GDB will be built with
1826 internationalization (libintl). The task of marking up the sources is
1827 continued, we're looking forward to our first translation.
1831 Initial support for debugging programs compiled with the GNAT
1832 implementation of the Ada programming language has been integrated
1833 into GDB. In this release, support is limited to expression evaluation.
1835 * New native configurations
1837 GNU/Linux/m32r m32r-*-linux-gnu
1841 GDB's remote protocol now includes support for the 'p' packet. This
1842 packet is used to fetch individual registers from a remote inferior.
1844 * END-OF-LIFE registers[] compatibility module
1846 GDB's internal register infrastructure has been completely rewritten.
1847 The new infrastructure making possible the implementation of key new
1848 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1851 GDB 6.3 will be the last release to include the the registers[]
1852 compatibility module that allowed out-of-date configurations to
1853 continue to work. This change directly impacts the following
1863 powerpc bdm protocol
1865 Unless there is activity to revive these configurations, they will be
1866 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1868 * OBSOLETE configurations and files
1870 Configurations that have been declared obsolete in this release have
1871 been commented out. Unless there is activity to revive these
1872 configurations, the next release of GDB will have their sources
1873 permanently REMOVED.
1882 *** Changes in GDB 6.2.1:
1884 * MIPS `break main; run' gave an heuristic-fence-post warning
1886 When attempting to run even a simple program, a warning about
1887 heuristic-fence-post being hit would be reported. This problem has
1890 * MIPS IRIX 'long double' crashed GDB
1892 When examining a long double variable, GDB would get a segmentation
1893 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1894 IRIX long double values).
1898 A bug in the VAX stack code was causing problems with the "next"
1899 command. This problem has been fixed.
1901 *** Changes in GDB 6.2:
1903 * Fix for ``many threads''
1905 On GNU/Linux systems that use the NPTL threads library, a program
1906 rapidly creating and deleting threads would confuse GDB leading to the
1909 ptrace: No such process.
1910 thread_db_get_info: cannot get thread info: generic error
1912 This problem has been fixed.
1914 * "-async" and "-noasync" options removed.
1916 Support for the broken "-noasync" option has been removed (it caused
1919 * New ``start'' command.
1921 This command runs the program until the begining of the main procedure.
1923 * New BSD Kernel Data Access Library (libkvm) interface
1925 Using ``target kvm'' it is now possible to debug kernel core dumps and
1926 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1927 platforms. Currently supported (native-only) configurations are:
1929 FreeBSD/amd64 x86_64-*-freebsd*
1930 FreeBSD/i386 i?86-*-freebsd*
1931 NetBSD/i386 i?86-*-netbsd*
1932 NetBSD/m68k m68*-*-netbsd*
1933 NetBSD/sparc sparc-*-netbsd*
1934 OpenBSD/amd64 x86_64-*-openbsd*
1935 OpenBSD/i386 i?86-*-openbsd*
1936 OpenBSD/m68k m68*-openbsd*
1937 OpenBSD/sparc sparc-*-openbsd*
1939 * Signal trampoline code overhauled
1941 Many generic problems with GDB's signal handling code have been fixed.
1942 These include: backtraces through non-contiguous stacks; recognition
1943 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1944 call; backtrace through a signal trampoline; step into and out of
1945 signal handlers; and single-stepping in the signal trampoline.
1947 Please note that kernel bugs are a limiting factor here. These
1948 features have been shown to work on an s390 GNU/Linux system that
1949 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1951 * Cygwin support for DWARF 2 added.
1953 * New native configurations
1955 GNU/Linux/hppa hppa*-*-linux*
1956 OpenBSD/hppa hppa*-*-openbsd*
1957 OpenBSD/m68k m68*-*-openbsd*
1958 OpenBSD/m88k m88*-*-openbsd*
1959 OpenBSD/powerpc powerpc-*-openbsd*
1960 NetBSD/vax vax-*-netbsd*
1961 OpenBSD/vax vax-*-openbsd*
1963 * END-OF-LIFE frame compatibility module
1965 GDB's internal frame infrastructure has been completely rewritten.
1966 The new infrastructure making it possible to support key new features
1967 including DWARF 2 Call Frame Information. To aid in the task of
1968 migrating old configurations to this new infrastructure, a
1969 compatibility module, that allowed old configurations to continue to
1970 work, was also included.
1972 GDB 6.2 will be the last release to include this frame compatibility
1973 module. This change directly impacts the following configurations:
1983 Unless there is activity to revive these configurations, they will be
1984 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1986 * REMOVED configurations and files
1988 Sun 3, running SunOS 3 m68*-*-sunos3*
1989 Sun 3, running SunOS 4 m68*-*-sunos4*
1990 Sun 2, running SunOS 3 m68000-*-sunos3*
1991 Sun 2, running SunOS 4 m68000-*-sunos4*
1992 Motorola 680x0 running LynxOS m68*-*-lynxos*
1993 AT&T 3b1/Unix pc m68*-att-*
1994 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1995 decstation mips-dec-* mips-little-*
1996 riscos mips-*-riscos* mips-*-sysv*
1997 sonymips mips-sony-*
1998 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2000 *** Changes in GDB 6.1.1:
2002 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2004 The TUI (Text-mode User Interface) is now built as part of a default
2005 GDB configuration. It is enabled by either selecting the TUI with the
2006 command line option "-i=tui" or by running the separate "gdbtui"
2007 program. For more information on the TUI, see the manual "Debugging
2010 * Pending breakpoint support (also included in GDB 6.1)
2012 Support has been added to allow you to specify breakpoints in shared
2013 libraries that have not yet been loaded. If a breakpoint location
2014 cannot be found, and the "breakpoint pending" option is set to auto,
2015 GDB queries you if you wish to make the breakpoint pending on a future
2016 shared-library load. If and when GDB resolves the breakpoint symbol,
2017 the pending breakpoint is removed as one or more regular breakpoints
2020 Pending breakpoints are very useful for GCJ Java debugging.
2022 * Fixed ISO-C build problems
2024 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2025 non ISO-C code that stopped them being built using a more strict ISO-C
2026 compiler (e.g., IBM's C compiler).
2028 * Fixed build problem on IRIX 5
2030 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2031 wasn't able to compile compile on an IRIX 5 system.
2033 * Added execute permission to gdb/gdbserver/configure
2035 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2036 permission. This bug would cause configure to fail on a number of
2037 systems (Solaris, IRIX). Ref: server/519.
2039 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2041 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2042 has been updated to use constant array sizes.
2044 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2046 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2047 its generated DWARF Call Frame Info. This encoding was causing GDB to
2048 panic, that panic has been fixed. Ref: gdb/1628.
2050 * Fixed a problem when examining parameters in shared library code.
2052 When examining parameters in optimized shared library code generated
2053 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2054 not available''. GDB now correctly displays the variable's value.
2056 *** Changes in GDB 6.1:
2058 * Removed --with-mmalloc
2060 Support for the mmalloc memory manager has been removed, as it
2061 conflicted with the internal gdb byte cache.
2063 * Changes in AMD64 configurations
2065 The AMD64 target now includes the %cs and %ss registers. As a result
2066 the AMD64 remote protocol has changed; this affects the floating-point
2067 and SSE registers. If you rely on those registers for your debugging,
2068 you should upgrade gdbserver on the remote side.
2070 * Revised SPARC target
2072 The SPARC target has been completely revised, incorporating the
2073 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2074 support for LynxOS and SunOS 4 has been dropped. Calling functions
2075 from within GDB on operating systems with a non-executable stack
2076 (Solaris, OpenBSD) now works.
2080 GDB has a new C++ demangler which does a better job on the mangled
2081 names generated by current versions of g++. It also runs faster, so
2082 with this and other changes gdb should now start faster on large C++
2085 * DWARF 2 Location Expressions
2087 GDB support for location expressions has been extended to support function
2088 arguments and frame bases. Older versions of GDB could crash when they
2091 * C++ nested types and namespaces
2093 GDB's support for nested types and namespaces in C++ has been
2094 improved, especially if you use the DWARF 2 debugging format. (This
2095 is the default for recent versions of GCC on most platforms.)
2096 Specifically, if you have a class "Inner" defined within a class or
2097 namespace "Outer", then GDB realizes that the class's name is
2098 "Outer::Inner", not simply "Inner". This should greatly reduce the
2099 frequency of complaints about not finding RTTI symbols. In addition,
2100 if you are stopped at inside of a function defined within a namespace,
2101 GDB modifies its name lookup accordingly.
2103 * New native configurations
2105 NetBSD/amd64 x86_64-*-netbsd*
2106 OpenBSD/amd64 x86_64-*-openbsd*
2107 OpenBSD/alpha alpha*-*-openbsd*
2108 OpenBSD/sparc sparc-*-openbsd*
2109 OpenBSD/sparc64 sparc64-*-openbsd*
2111 * New debugging protocols
2113 M32R with SDI protocol m32r-*-elf*
2115 * "set prompt-escape-char" command deleted.
2117 The command "set prompt-escape-char" has been deleted. This command,
2118 and its very obscure effet on GDB's prompt, was never documented,
2119 tested, nor mentioned in the NEWS file.
2121 * OBSOLETE configurations and files
2123 Configurations that have been declared obsolete in this release have
2124 been commented out. Unless there is activity to revive these
2125 configurations, the next release of GDB will have their sources
2126 permanently REMOVED.
2128 Sun 3, running SunOS 3 m68*-*-sunos3*
2129 Sun 3, running SunOS 4 m68*-*-sunos4*
2130 Sun 2, running SunOS 3 m68000-*-sunos3*
2131 Sun 2, running SunOS 4 m68000-*-sunos4*
2132 Motorola 680x0 running LynxOS m68*-*-lynxos*
2133 AT&T 3b1/Unix pc m68*-att-*
2134 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2135 decstation mips-dec-* mips-little-*
2136 riscos mips-*-riscos* mips-*-sysv*
2137 sonymips mips-sony-*
2138 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2140 * REMOVED configurations and files
2142 SGI Irix-4.x mips-sgi-irix4 or iris4
2143 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2144 Z8000 simulator z8k-zilog-none or z8ksim
2145 Matsushita MN10200 w/simulator mn10200-*-*
2146 H8/500 simulator h8500-hitachi-hms or h8500hms
2147 HP/PA running BSD hppa*-*-bsd*
2148 HP/PA running OSF/1 hppa*-*-osf*
2149 HP/PA Pro target hppa*-*-pro*
2150 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2151 386BSD i[3456]86-*-bsd*
2152 Sequent family i[3456]86-sequent-sysv4*
2153 i[3456]86-sequent-sysv*
2154 i[3456]86-sequent-bsd*
2155 SPARC running LynxOS sparc-*-lynxos*
2156 SPARC running SunOS 4 sparc-*-sunos4*
2157 Tsqware Sparclet sparclet-*-*
2158 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2160 *** Changes in GDB 6.0:
2164 Support for debugging the Objective-C programming language has been
2165 integrated into GDB.
2167 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2169 DWARF 2's Call Frame Information makes available compiler generated
2170 information that more exactly describes the program's run-time stack.
2171 By using this information, GDB is able to provide more robust stack
2174 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2175 have been updated to use a new backtrace mechanism which includes
2176 DWARF 2 CFI support.
2180 GDB's remote protocol has been extended to include support for hosted
2181 file I/O (where the remote target uses GDB's file system). See GDB's
2182 remote protocol documentation for details.
2184 * All targets using the new architecture framework.
2186 All of GDB's targets have been updated to use the new internal
2187 architecture framework. The way is now open for future GDB releases
2188 to include cross-architecture native debugging support (i386 on amd64,
2191 * GNU/Linux's Thread Local Storage (TLS)
2193 GDB now includes support for for the GNU/Linux implementation of
2194 per-thread variables.
2196 * GNU/Linux's Native POSIX Thread Library (NPTL)
2198 GDB's thread code has been updated to work with either the new
2199 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2201 * Separate debug info.
2203 GDB, in conjunction with BINUTILS, now supports a mechanism for
2204 automatically loading debug information from a separate file. Instead
2205 of shipping full debug and non-debug versions of system libraries,
2206 system integrators can now instead ship just the stripped libraries
2207 and optional debug files.
2209 * DWARF 2 Location Expressions
2211 DWARF 2 Location Expressions allow the compiler to more completely
2212 describe the location of variables (even in optimized code) to the
2215 GDB now includes preliminary support for location expressions (support
2216 for DW_OP_piece is still missing).
2220 A number of long standing bugs that caused GDB to die while starting a
2221 Java application have been fixed. GDB's Java support is now
2222 considered "useable".
2224 * GNU/Linux support for fork, vfork, and exec.
2226 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2227 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2230 * GDB supports logging output to a file
2232 There are two new commands, "set logging" and "show logging", which can be
2233 used to capture GDB's output to a file.
2235 * The meaning of "detach" has changed for gdbserver
2237 The "detach" command will now resume the application, as documented. To
2238 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2241 * d10v, m68hc11 `regs' command deprecated
2243 The `info registers' command has been updated so that it displays the
2244 registers using a format identical to the old `regs' command.
2248 A new command, "maint set profile on/off", has been added. This command can
2249 be used to enable or disable profiling while running GDB, to profile a
2250 session or a set of commands. In addition there is a new configure switch,
2251 "--enable-profiling", which will cause GDB to be compiled with profiling
2252 data, for more informative profiling results.
2254 * Default MI syntax changed to "mi2".
2256 The default MI (machine interface) syntax, enabled by the command line
2257 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2258 "mi1", can be enabled by specifying the option "-i=mi1".
2260 Support for the original "mi0" syntax (included in GDB 5.0) has been
2263 Fix for gdb/192: removed extraneous space when displaying frame level.
2264 Fix for gdb/672: update changelist is now output in mi list format.
2265 Fix for gdb/702: a -var-assign that updates the value now shows up
2266 in a subsequent -var-update.
2268 * New native configurations.
2270 FreeBSD/amd64 x86_64-*-freebsd*
2272 * Multi-arched targets.
2274 HP/PA HPUX11 hppa*-*-hpux*
2275 Renesas M32R/D w/simulator m32r-*-elf*
2277 * OBSOLETE configurations and files
2279 Configurations that have been declared obsolete in this release have
2280 been commented out. Unless there is activity to revive these
2281 configurations, the next release of GDB will have their sources
2282 permanently REMOVED.
2284 Z8000 simulator z8k-zilog-none or z8ksim
2285 Matsushita MN10200 w/simulator mn10200-*-*
2286 H8/500 simulator h8500-hitachi-hms or h8500hms
2287 HP/PA running BSD hppa*-*-bsd*
2288 HP/PA running OSF/1 hppa*-*-osf*
2289 HP/PA Pro target hppa*-*-pro*
2290 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2291 Sequent family i[3456]86-sequent-sysv4*
2292 i[3456]86-sequent-sysv*
2293 i[3456]86-sequent-bsd*
2294 Tsqware Sparclet sparclet-*-*
2295 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2297 * REMOVED configurations and files
2300 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2301 IBM AIX PS/2 i[3456]86-*-aix
2302 i386 running Mach 3.0 i[3456]86-*-mach3*
2303 i386 running Mach i[3456]86-*-mach*
2304 i386 running OSF/1 i[3456]86-*osf1mk*
2305 HP/Apollo 68k Family m68*-apollo*-sysv*,
2307 m68*-hp-bsd*, m68*-hp-hpux*
2308 Argonaut Risc Chip (ARC) arc-*-*
2309 Mitsubishi D30V d30v-*-*
2310 Fujitsu FR30 fr30-*-elf*
2311 OS/9000 i[34]86-*-os9k
2312 I960 with MON960 i960-*-coff
2314 * MIPS $fp behavior changed
2316 The convenience variable $fp, for the MIPS, now consistently returns
2317 the address of the current frame's base. Previously, depending on the
2318 context, $fp could refer to either $sp or the current frame's base
2319 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2320 The GNU Source-Level Debugger''.
2322 *** Changes in GDB 5.3:
2324 * GNU/Linux shared library multi-threaded performance improved.
2326 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2327 `/proc', in preference to `ptrace' for memory reads. This may result
2328 in an improvement in the start-up time of multi-threaded, shared
2329 library applications when run under GDB. One GDB user writes: ``loads
2330 shared libs like mad''.
2332 * ``gdbserver'' now supports multi-threaded applications on some targets
2334 Support for debugging multi-threaded applications which use
2335 the GNU/Linux LinuxThreads package has been added for
2336 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2337 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2339 * GDB now supports C/C++ preprocessor macros.
2341 GDB now expands preprocessor macro invocations in C/C++ expressions,
2342 and provides various commands for showing macro definitions and how
2345 The new command `macro expand EXPRESSION' expands any macro
2346 invocations in expression, and shows the result.
2348 The new command `show macro MACRO-NAME' shows the definition of the
2349 macro named MACRO-NAME, and where it was defined.
2351 Most compilers don't include information about macros in the debugging
2352 information by default. In GCC 3.1, for example, you need to compile
2353 your program with the options `-gdwarf-2 -g3'. If the macro
2354 information is present in the executable, GDB will read it.
2356 * Multi-arched targets.
2358 DEC Alpha (partial) alpha*-*-*
2359 DEC VAX (partial) vax-*-*
2361 National Semiconductor NS32000 (partial) ns32k-*-*
2362 Motorola 68000 (partial) m68k-*-*
2363 Motorola MCORE mcore-*-*
2367 Fujitsu FRV architecture added by Red Hat frv*-*-*
2370 * New native configurations
2372 Alpha NetBSD alpha*-*-netbsd*
2373 SH NetBSD sh*-*-netbsdelf*
2374 MIPS NetBSD mips*-*-netbsd*
2375 UltraSPARC NetBSD sparc64-*-netbsd*
2377 * OBSOLETE configurations and files
2379 Configurations that have been declared obsolete in this release have
2380 been commented out. Unless there is activity to revive these
2381 configurations, the next release of GDB will have their sources
2382 permanently REMOVED.
2384 Mitsubishi D30V d30v-*-*
2385 OS/9000 i[34]86-*-os9k
2386 IBM AIX PS/2 i[3456]86-*-aix
2387 Fujitsu FR30 fr30-*-elf*
2388 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2389 Argonaut Risc Chip (ARC) arc-*-*
2390 i386 running Mach 3.0 i[3456]86-*-mach3*
2391 i386 running Mach i[3456]86-*-mach*
2392 i386 running OSF/1 i[3456]86-*osf1mk*
2393 HP/Apollo 68k Family m68*-apollo*-sysv*,
2395 m68*-hp-bsd*, m68*-hp-hpux*
2396 I960 with MON960 i960-*-coff
2398 * OBSOLETE languages
2400 CHILL, a Pascal like language used by telecommunications companies.
2402 * REMOVED configurations and files
2404 AMD 29k family via UDI a29k-amd-udi, udi29k
2405 A29K VxWorks a29k-*-vxworks
2406 AMD 29000 embedded, using EBMON a29k-none-none
2407 AMD 29000 embedded with COFF a29k-none-coff
2408 AMD 29000 embedded with a.out a29k-none-aout
2410 testsuite/gdb.hp/gdb.threads-hp/ directory
2412 * New command "set max-user-call-depth <nnn>"
2414 This command allows the user to limit the call depth of user-defined
2415 commands. The default is 1024.
2417 * Changes in FreeBSD/i386 native debugging.
2419 Support for the "generate-core-file" has been added.
2421 * New commands "dump", "append", and "restore".
2423 These commands allow data to be copied from target memory
2424 to a bfd-format or binary file (dump and append), and back
2425 from a file into memory (restore).
2427 * Improved "next/step" support on multi-processor Alpha Tru64.
2429 The previous single-step mechanism could cause unpredictable problems,
2430 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2431 of a software single-step mechanism prevents this.
2433 *** Changes in GDB 5.2.1:
2441 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2442 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2443 Fix, by Joel Brobecker imported from mainline.
2445 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2446 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2447 Fix, by Fred Fish, imported from mainline.
2449 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2450 Surprisingly enough, it works now.
2451 By Michal Ludvig, imported from mainline.
2453 i386 hardware watchpoint support:
2454 avoid misses on second run for some targets.
2455 By Pierre Muller, imported from mainline.
2457 *** Changes in GDB 5.2:
2459 * New command "set trust-readonly-sections on[off]".
2461 This command is a hint that tells gdb that read-only sections
2462 really are read-only (ie. that their contents will not change).
2463 In this mode, gdb will go to the object file rather than the
2464 target to read memory from read-only sections (such as ".text").
2465 This can be a significant performance improvement on some
2466 (notably embedded) targets.
2468 * New command "generate-core-file" (or "gcore").
2470 This new gdb command allows the user to drop a core file of the child
2471 process state at any time. So far it's been implemented only for
2472 GNU/Linux and Solaris, but should be relatively easily ported to other
2473 hosts. Argument is core file name (defaults to core.<pid>).
2475 * New command line option
2477 GDB now accepts --pid or -p followed by a process id.
2479 * Change in command line behavior -- corefiles vs. process ids.
2481 There is a subtle behavior in the way in which GDB handles
2482 command line arguments. The first non-flag argument is always
2483 a program to debug, but the second non-flag argument may either
2484 be a corefile or a process id. Previously, GDB would attempt to
2485 open the second argument as a corefile, and if that failed, would
2486 issue a superfluous error message and then attempt to attach it as
2487 a process. Now, if the second argument begins with a non-digit,
2488 it will be treated as a corefile. If it begins with a digit,
2489 GDB will attempt to attach it as a process, and if no such process
2490 is found, will then attempt to open it as a corefile.
2492 * Changes in ARM configurations.
2494 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2495 configuration is fully multi-arch.
2497 * New native configurations
2499 ARM NetBSD arm*-*-netbsd*
2500 x86 OpenBSD i[3456]86-*-openbsd*
2501 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2502 Sparc64 running FreeBSD sparc64-*-freebsd*
2506 Sanyo XStormy16 xstormy16-elf
2508 * OBSOLETE configurations and files
2510 Configurations that have been declared obsolete in this release have
2511 been commented out. Unless there is activity to revive these
2512 configurations, the next release of GDB will have their sources
2513 permanently REMOVED.
2515 AMD 29k family via UDI a29k-amd-udi, udi29k
2516 A29K VxWorks a29k-*-vxworks
2517 AMD 29000 embedded, using EBMON a29k-none-none
2518 AMD 29000 embedded with COFF a29k-none-coff
2519 AMD 29000 embedded with a.out a29k-none-aout
2521 testsuite/gdb.hp/gdb.threads-hp/ directory
2523 * REMOVED configurations and files
2525 TI TMS320C80 tic80-*-*
2527 PowerPC Solaris powerpcle-*-solaris*
2528 PowerPC Windows NT powerpcle-*-cygwin32
2529 PowerPC Netware powerpc-*-netware*
2530 Harris/CXUX m88k m88*-harris-cxux*
2531 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2532 ns32k-utek-sysv* ns32k-utek-*
2533 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2534 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2535 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2536 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2537 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2539 * Changes to command line processing
2541 The new `--args' feature can be used to specify command-line arguments
2542 for the inferior from gdb's command line.
2544 * Changes to key bindings
2546 There is a new `operate-and-get-next' function bound to `C-o'.
2548 *** Changes in GDB 5.1.1
2550 Fix compile problem on DJGPP.
2552 Fix a problem with floating-point registers on the i386 being
2555 Fix to stop GDB crashing on .debug_str debug info.
2557 Numerous documentation fixes.
2559 Numerous testsuite fixes.
2561 *** Changes in GDB 5.1:
2563 * New native configurations
2565 Alpha FreeBSD alpha*-*-freebsd*
2566 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2567 MIPS GNU/Linux mips*-*-linux*
2568 MIPS SGI Irix 6.x mips*-sgi-irix6*
2569 ia64 AIX ia64-*-aix*
2570 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2574 Motorola 68HC11 and 68HC12 m68hc11-elf
2576 UltraSparc running GNU/Linux sparc64-*-linux*
2578 * OBSOLETE configurations and files
2580 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2581 Harris/CXUX m88k m88*-harris-cxux*
2582 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2583 ns32k-utek-sysv* ns32k-utek-*
2584 TI TMS320C80 tic80-*-*
2586 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2587 PowerPC Solaris powerpcle-*-solaris*
2588 PowerPC Windows NT powerpcle-*-cygwin32
2589 PowerPC Netware powerpc-*-netware*
2590 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2591 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2592 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2593 Apple Macintosh (MPW) host N/A
2595 stuff.c (Program to stuff files into a specially prepared space in kdb)
2596 kdb-start.c (Main loop for the standalone kernel debugger)
2598 Configurations that have been declared obsolete in this release have
2599 been commented out. Unless there is activity to revive these
2600 configurations, the next release of GDB will have their sources
2601 permanently REMOVED.
2603 * REMOVED configurations and files
2605 Altos 3068 m68*-altos-*
2606 Convex c1-*-*, c2-*-*
2608 ARM RISCix arm-*-* (as host)
2612 * GDB has been converted to ISO C.
2614 GDB's source code has been converted to ISO C. In particular, the
2615 sources are fully protoized, and rely on standard headers being
2620 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2622 * The MI enabled by default.
2624 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2625 revised and enabled by default. Packages which use GDB as a debugging
2626 engine behind a UI or another front end are encouraged to switch to
2627 using the GDB/MI interface, instead of the old annotations interface
2628 which is now deprecated.
2630 * Support for debugging Pascal programs.
2632 GDB now includes support for debugging Pascal programs. The following
2633 main features are supported:
2635 - Pascal-specific data types such as sets;
2637 - automatic recognition of Pascal sources based on file-name
2640 - Pascal-style display of data types, variables, and functions;
2642 - a Pascal expression parser.
2644 However, some important features are not yet supported.
2646 - Pascal string operations are not supported at all;
2648 - there are some problems with boolean types;
2650 - Pascal type hexadecimal constants are not supported
2651 because they conflict with the internal variables format;
2653 - support for Pascal objects and classes is not full yet;
2655 - unlike Pascal, GDB is case-sensitive for symbol names.
2657 * Changes in completion.
2659 Commands such as `shell', `run' and `set args', which pass arguments
2660 to inferior programs, now complete on file names, similar to what
2661 users expect at the shell prompt.
2663 Commands which accept locations, such as `disassemble', `print',
2664 `breakpoint', `until', etc. now complete on filenames as well as
2665 program symbols. Thus, if you type "break foob TAB", and the source
2666 files linked into the programs include `foobar.c', that file name will
2667 be one of the candidates for completion. However, file names are not
2668 considered for completion after you typed a colon that delimits a file
2669 name from a name of a function in that file, as in "break foo.c:bar".
2671 `set demangle-style' completes on available demangling styles.
2673 * New platform-independent commands:
2675 It is now possible to define a post-hook for a command as well as a
2676 hook that runs before the command. For more details, see the
2677 documentation of `hookpost' in the GDB manual.
2679 * Changes in GNU/Linux native debugging.
2681 Support for debugging multi-threaded programs has been completely
2682 revised for all platforms except m68k and sparc. You can now debug as
2683 many threads as your system allows you to have.
2685 Attach/detach is supported for multi-threaded programs.
2687 Support for SSE registers was added for x86. This doesn't work for
2688 multi-threaded programs though.
2690 * Changes in MIPS configurations.
2692 Multi-arch support is enabled for all MIPS configurations.
2694 GDB can now be built as native debugger on SGI Irix 6.x systems for
2695 debugging n32 executables. (Debugging 64-bit executables is not yet
2698 * Unified support for hardware watchpoints in all x86 configurations.
2700 Most (if not all) native x86 configurations support hardware-assisted
2701 breakpoints and watchpoints in a unified manner. This support
2702 implements debug register sharing between watchpoints, which allows to
2703 put a virtually infinite number of watchpoints on the same address,
2704 and also supports watching regions up to 16 bytes with several debug
2707 The new maintenance command `maintenance show-debug-regs' toggles
2708 debugging print-outs in functions that insert, remove, and test
2709 watchpoints and hardware breakpoints.
2711 * Changes in the DJGPP native configuration.
2713 New command ``info dos sysinfo'' displays assorted information about
2714 the CPU, OS, memory, and DPMI server.
2716 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2717 display information about segment descriptors stored in GDT, LDT, and
2720 New commands ``info dos pde'' and ``info dos pte'' display entries
2721 from Page Directory and Page Tables (for now works with CWSDPMI only).
2722 New command ``info dos address-pte'' displays the Page Table entry for
2723 a given linear address.
2725 GDB can now pass command lines longer than 126 characters to the
2726 program being debugged (requires an update to the libdbg.a library
2727 which is part of the DJGPP development kit).
2729 DWARF2 debug info is now supported.
2731 It is now possible to `step' and `next' through calls to `longjmp'.
2733 * Changes in documentation.
2735 All GDB documentation was converted to GFDL, the GNU Free
2736 Documentation License.
2738 Tracepoints-related commands are now fully documented in the GDB
2741 TUI, the Text-mode User Interface, is now documented in the manual.
2743 Tracepoints-related commands are now fully documented in the GDB
2746 The "GDB Internals" manual now has an index. It also includes
2747 documentation of `ui_out' functions, GDB coding standards, x86
2748 hardware watchpoints, and memory region attributes.
2750 * GDB's version number moved to ``version.in''
2752 The Makefile variable VERSION has been replaced by the file
2753 ``version.in''. People creating GDB distributions should update the
2754 contents of this file.
2758 GUD support is now a standard part of the EMACS distribution.
2760 *** Changes in GDB 5.0:
2762 * Improved support for debugging FP programs on x86 targets
2764 Unified and much-improved support for debugging floating-point
2765 programs on all x86 targets. In particular, ``info float'' now
2766 displays the FP registers in the same format on all x86 targets, with
2767 greater level of detail.
2769 * Improvements and bugfixes in hardware-assisted watchpoints
2771 It is now possible to watch array elements, struct members, and
2772 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2773 on x86 targets no longer erroneously trigger when the address is
2776 * Improvements in the native DJGPP version of GDB
2778 The distribution now includes all the scripts and auxiliary files
2779 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2780 machines ``out of the box''.
2782 The DJGPP version can now debug programs that use signals. It is
2783 possible to catch signals that happened in the debuggee, deliver
2784 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2785 would kill the program being debugged.) Programs that hook hardware
2786 interrupts (keyboard, timer, etc.) can also be debugged.
2788 It is now possible to debug DJGPP programs that redirect their
2789 standard handles or switch them to raw (as opposed to cooked) mode, or
2790 even close them. The command ``run < foo > bar'' works as expected,
2791 and ``info terminal'' reports useful information about the debuggee's
2792 terminal, including raw/cooked mode, redirection, etc.
2794 The DJGPP version now uses termios functions for console I/O, which
2795 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2798 DOS-style file names with drive letters are now fully supported by
2801 It is now possible to debug DJGPP programs that switch their working
2802 directory. It is also possible to rerun the debuggee any number of
2803 times without restarting GDB; thus, you can use the same setup,
2804 breakpoints, etc. for many debugging sessions.
2806 * New native configurations
2808 ARM GNU/Linux arm*-*-linux*
2809 PowerPC GNU/Linux powerpc-*-linux*
2813 Motorola MCore mcore-*-*
2814 x86 VxWorks i[3456]86-*-vxworks*
2815 PowerPC VxWorks powerpc-*-vxworks*
2816 TI TMS320C80 tic80-*-*
2818 * OBSOLETE configurations
2820 Altos 3068 m68*-altos-*
2821 Convex c1-*-*, c2-*-*
2823 ARM RISCix arm-*-* (as host)
2826 Configurations that have been declared obsolete will be commented out,
2827 but the code will be left in place. If there is no activity to revive
2828 these configurations before the next release of GDB, the sources will
2829 be permanently REMOVED.
2831 * Gould support removed
2833 Support for the Gould PowerNode and NP1 has been removed.
2835 * New features for SVR4
2837 On SVR4 native platforms (such as Solaris), if you attach to a process
2838 without first loading a symbol file, GDB will now attempt to locate and
2839 load symbols from the running process's executable file.
2841 * Many C++ enhancements
2843 C++ support has been greatly improved. Overload resolution now works properly
2844 in almost all cases. RTTI support is on the way.
2846 * Remote targets can connect to a sub-program
2848 A popen(3) style serial-device has been added. This device starts a
2849 sub-process (such as a stand-alone simulator) and then communicates
2850 with that. The sub-program to run is specified using the syntax
2851 ``|<program> <args>'' vis:
2853 (gdb) set remotedebug 1
2854 (gdb) target extended-remote |mn10300-elf-sim program-args
2856 * MIPS 64 remote protocol
2858 A long standing bug in the mips64 remote protocol where by GDB
2859 expected certain 32 bit registers (ex SR) to be transfered as 32
2860 instead of 64 bits has been fixed.
2862 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2863 added to provide backward compatibility with older versions of GDB.
2865 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2867 The command ``set remotebinarydownload'' command has been replaced by
2868 ``set remote X-packet''. Other commands in ``set remote'' family
2869 include ``set remote P-packet''.
2871 * Breakpoint commands accept ranges.
2873 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2874 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2875 ``tracepoint passcount'' also accepts a range of tracepoints.
2877 * ``apropos'' command added.
2879 The ``apropos'' command searches through command names and
2880 documentation strings, printing out matches, making it much easier to
2881 try to find a command that does what you are looking for.
2885 A new machine oriented interface (MI) has been added to GDB. This
2886 interface is designed for debug environments running GDB as a separate
2887 process. This is part of the long term libGDB project. See the
2888 "GDB/MI" chapter of the GDB manual for further information. It can be
2889 enabled by configuring with:
2891 .../configure --enable-gdbmi
2893 *** Changes in GDB-4.18:
2895 * New native configurations
2897 HP-UX 10.20 hppa*-*-hpux10.20
2898 HP-UX 11.x hppa*-*-hpux11.0*
2899 M68K GNU/Linux m68*-*-linux*
2903 Fujitsu FR30 fr30-*-elf*
2904 Intel StrongARM strongarm-*-*
2905 Mitsubishi D30V d30v-*-*
2907 * OBSOLETE configurations
2909 Gould PowerNode, NP1 np1-*-*, pn-*-*
2911 Configurations that have been declared obsolete will be commented out,
2912 but the code will be left in place. If there is no activity to revive
2913 these configurations before the next release of GDB, the sources will
2914 be permanently REMOVED.
2918 As a compatibility experiment, GDB's source files buildsym.h and
2919 buildsym.c have been converted to pure standard C, no longer
2920 containing any K&R compatibility code. We believe that all systems in
2921 use today either come with a standard C compiler, or have a GCC port
2922 available. If this is not true, please report the affected
2923 configuration to bug-gdb@gnu.org immediately. See the README file for
2924 information about getting a standard C compiler if you don't have one
2929 GDB now uses readline 2.2.
2931 * set extension-language
2933 You can now control the mapping between filename extensions and source
2934 languages by using the `set extension-language' command. For instance,
2935 you can ask GDB to treat .c files as C++ by saying
2936 set extension-language .c c++
2937 The command `info extensions' lists all of the recognized extensions
2938 and their associated languages.
2940 * Setting processor type for PowerPC and RS/6000
2942 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2943 you can use the `set processor' command to specify what variant of the
2944 PowerPC family you are debugging. The command
2948 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2949 following PowerPC and RS6000 variants:
2951 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2952 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2954 403GC IBM PowerPC 403GC
2955 505 Motorola PowerPC 505
2956 860 Motorola PowerPC 860 or 850
2957 601 Motorola PowerPC 601
2958 602 Motorola PowerPC 602
2959 603 Motorola/IBM PowerPC 603 or 603e
2960 604 Motorola PowerPC 604 or 604e
2961 750 Motorola/IBM PowerPC 750 or 750
2963 At the moment, this command just tells GDB what to name the
2964 special-purpose processor registers. Since almost all the affected
2965 registers are inaccessible to user-level programs, this command is
2966 only useful for remote debugging in its present form.
2970 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2971 more extensive support for HP-UX. Added features include shared
2972 library support, kernel threads and hardware watchpoints for 11.00,
2973 support for HP's ANSI C and C++ compilers, and a compatibility mode
2974 for xdb and dbx commands.
2978 HP's donation includes the new concept of catchpoints, which is a
2979 generalization of the old catch command. On HP-UX, it is now possible
2980 to catch exec, fork, and vfork, as well as library loading.
2982 This means that the existing catch command has changed; its first
2983 argument now specifies the type of catch to be set up. See the
2984 output of "help catch" for a list of catchpoint types.
2986 * Debugging across forks
2988 On HP-UX, you can choose which process to debug when a fork() happens
2993 HP has donated a curses-based terminal user interface (TUI). To get
2994 it, build with --enable-tui. Although this can be enabled for any
2995 configuration, at present it only works for native HP debugging.
2997 * GDB remote protocol additions
2999 A new protocol packet 'X' that writes binary data is now available.
3000 Default behavior is to try 'X', then drop back to 'M' if the stub
3001 fails to respond. The settable variable `remotebinarydownload'
3002 allows explicit control over the use of 'X'.
3004 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3005 full 64-bit address. The command
3007 set remoteaddresssize 32
3009 can be used to revert to the old behaviour. For existing remote stubs
3010 the change should not be noticed, as the additional address information
3013 In order to assist in debugging stubs, you may use the maintenance
3014 command `packet' to send any text string to the stub. For instance,
3016 maint packet heythere
3018 sends the packet "$heythere#<checksum>". Note that it is very easy to
3019 disrupt a debugging session by sending the wrong packet at the wrong
3022 The compare-sections command allows you to compare section data on the
3023 target to what is in the executable file without uploading or
3024 downloading, by comparing CRC checksums.
3026 * Tracing can collect general expressions
3028 You may now collect general expressions at tracepoints. This requires
3029 further additions to the target-side stub; see tracepoint.c and
3030 doc/agentexpr.texi for further details.
3032 * mask-address variable for Mips
3034 For Mips targets, you may control the zeroing of the upper 32 bits of
3035 a 64-bit address by entering `set mask-address on'. This is mainly
3036 of interest to users of embedded R4xxx and R5xxx processors.
3038 * Higher serial baud rates
3040 GDB's serial code now allows you to specify baud rates 57600, 115200,
3041 230400, and 460800 baud. (Note that your host system may not be able
3042 to achieve all of these rates.)
3046 The i960 configuration now includes an initial implementation of a
3047 builtin simulator, contributed by Jim Wilson.
3050 *** Changes in GDB-4.17:
3052 * New native configurations
3054 Alpha GNU/Linux alpha*-*-linux*
3055 Unixware 2.x i[3456]86-unixware2*
3056 Irix 6.x mips*-sgi-irix6*
3057 PowerPC GNU/Linux powerpc-*-linux*
3058 PowerPC Solaris powerpcle-*-solaris*
3059 Sparc GNU/Linux sparc-*-linux*
3060 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3064 Argonaut Risc Chip (ARC) arc-*-*
3065 Hitachi H8/300S h8300*-*-*
3066 Matsushita MN10200 w/simulator mn10200-*-*
3067 Matsushita MN10300 w/simulator mn10300-*-*
3068 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3069 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3070 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3071 Mitsubishi D10V w/simulator d10v-*-*
3072 Mitsubishi M32R/D w/simulator m32r-*-elf*
3073 Tsqware Sparclet sparclet-*-*
3074 NEC V850 w/simulator v850-*-*
3076 * New debugging protocols
3078 ARM with RDI protocol arm*-*-*
3079 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3080 DDB and LSI variants of PMON protocol mips*-*-*
3081 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3082 PowerPC with SDS protocol powerpc{,le}-*-eabi
3083 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3087 All configurations can now understand and use the DWARF 2 debugging
3088 format. The choice is automatic, if the symbol file contains DWARF 2
3093 GDB now includes basic Java language support. This support is
3094 only useful with Java compilers that produce native machine code.
3096 * solib-absolute-prefix and solib-search-path
3098 For SunOS and SVR4 shared libraries, you may now set the prefix for
3099 loading absolute shared library symbol files, and the search path for
3100 locating non-absolute shared library symbol files.
3102 * Live range splitting
3104 GDB can now effectively debug code for which GCC has performed live
3105 range splitting as part of its optimization. See gdb/doc/LRS for
3106 more details on the expected format of the stabs information.
3110 GDB's support for the GNU Hurd, including thread debugging, has been
3111 updated to work with current versions of the Hurd.
3115 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3116 instruction set. ARM GDB automatically detects when Thumb
3117 instructions are in use, and adjusts disassembly and backtracing
3122 GDB's MIPS target configurations now handle the MIP16 16-bit
3127 GDB now includes support for overlays; if an executable has been
3128 linked such that multiple sections are based at the same address, GDB
3129 will decide which section to use for symbolic info. You can choose to
3130 control the decision manually, using overlay commands, or implement
3131 additional target-side support and use "overlay load-target" to bring
3132 in the overlay mapping. Do "help overlay" for more detail.
3136 The command "info symbol <address>" displays information about
3137 the symbol at the specified address.
3141 The standard remote protocol now includes an extension that allows
3142 asynchronous collection and display of trace data. This requires
3143 extensive support in the target-side debugging stub. Tracing mode
3144 includes a new interaction mode in GDB and new commands: see the
3145 file tracepoint.c for more details.
3149 Configurations for embedded MIPS now include a simulator contributed
3150 by Cygnus Solutions. The simulator supports the instruction sets
3151 of most MIPS variants.
3155 Sparc configurations may now include the ERC32 simulator contributed
3156 by the European Space Agency. The simulator is not built into
3157 Sparc targets by default; configure with --enable-sim to include it.
3161 For target configurations that may include multiple variants of a
3162 basic architecture (such as MIPS and SH), you may now set the
3163 architecture explicitly. "set arch" sets, "info arch" lists
3164 the possible architectures.
3166 *** Changes in GDB-4.16:
3168 * New native configurations
3170 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3171 M68K NetBSD m68k-*-netbsd*
3172 PowerPC AIX 4.x powerpc-*-aix*
3173 PowerPC MacOS powerpc-*-macos*
3174 PowerPC Windows NT powerpcle-*-cygwin32
3175 RS/6000 AIX 4.x rs6000-*-aix4*
3179 ARM with RDP protocol arm-*-*
3180 I960 with MON960 i960-*-coff
3181 MIPS VxWorks mips*-*-vxworks*
3182 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3183 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3185 Matra Sparclet sparclet-*-*
3189 The powerpc-eabi configuration now includes the PSIM simulator,
3190 contributed by Andrew Cagney, with assistance from Mike Meissner.
3191 PSIM is a very elaborate model of the PowerPC, including not only
3192 basic instruction set execution, but also details of execution unit
3193 performance and I/O hardware. See sim/ppc/README for more details.
3197 GDB now works with Solaris 2.5.
3199 * Windows 95/NT native
3201 GDB will now work as a native debugger on Windows 95 and Windows NT.
3202 To build it from source, you must use the "gnu-win32" environment,
3203 which uses a DLL to emulate enough of Unix to run the GNU tools.
3204 Further information, binaries, and sources are available at
3205 ftp.cygnus.com, under pub/gnu-win32.
3207 * dont-repeat command
3209 If a user-defined command includes the command `dont-repeat', then the
3210 command will not be repeated if the user just types return. This is
3211 useful if the command is time-consuming to run, so that accidental
3212 extra keystrokes don't run the same command many times.
3214 * Send break instead of ^C
3216 The standard remote protocol now includes an option to send a break
3217 rather than a ^C to the target in order to interrupt it. By default,
3218 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3220 * Remote protocol timeout
3222 The standard remote protocol includes a new variable `remotetimeout'
3223 that allows you to set the number of seconds before GDB gives up trying
3224 to read from the target. The default value is 2.
3226 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3228 By default GDB will automatically keep track of objects as they are
3229 loaded and unloaded by the dynamic linker. By using the command `set
3230 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3231 when shared library events occur, thus allowing you to set breakpoints
3232 in shared libraries which are explicitly loaded by the inferior.
3234 Note this feature does not work on hpux8. On hpux9 you must link
3235 /usr/lib/end.o into your program. This feature should work
3236 automatically on hpux10.
3238 * Irix 5.x hardware watchpoint support
3240 Irix 5 configurations now support the use of hardware watchpoints.
3242 * Mips protocol "SYN garbage limit"
3244 When debugging a Mips target using the `target mips' protocol, you
3245 may set the number of characters that GDB will ignore by setting
3246 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3247 every character. The default value is 1050.
3249 * Recording and replaying remote debug sessions
3251 If you set `remotelogfile' to the name of a file, gdb will write to it
3252 a recording of a remote debug session. This recording may then be
3253 replayed back to gdb using "gdbreplay". See gdbserver/README for
3254 details. This is useful when you have a problem with GDB while doing
3255 remote debugging; you can make a recording of the session and send it
3256 to someone else, who can then recreate the problem.
3258 * Speedups for remote debugging
3260 GDB includes speedups for downloading and stepping MIPS systems using
3261 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3262 and more efficient S-record downloading.
3264 * Memory use reductions and statistics collection
3266 GDB now uses less memory and reports statistics about memory usage.
3267 Try the `maint print statistics' command, for example.
3269 *** Changes in GDB-4.15:
3271 * Psymtabs for XCOFF
3273 The symbol reader for AIX GDB now uses partial symbol tables. This
3274 can greatly improve startup time, especially for large executables.
3276 * Remote targets use caching
3278 Remote targets now use a data cache to speed up communication with the
3279 remote side. The data cache could lead to incorrect results because
3280 it doesn't know about volatile variables, thus making it impossible to
3281 debug targets which use memory mapped I/O devices. `set remotecache
3282 off' turns the the data cache off.
3284 * Remote targets may have threads
3286 The standard remote protocol now includes support for multiple threads
3287 in the target system, using new protocol commands 'H' and 'T'. See
3288 gdb/remote.c for details.
3292 If GDB is configured with `--enable-netrom', then it will include
3293 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3294 acts as though it is a bank of ROM on the target board, but you can
3295 write into it over the network. GDB's support consists only of
3296 support for fast loading into the emulated ROM; to debug, you must use
3297 another protocol, such as standard remote protocol. The usual
3298 sequence is something like
3300 target nrom <netrom-hostname>
3302 target remote <netrom-hostname>:1235
3306 GDB now includes support for the Apple Macintosh, as a host only. It
3307 may be run as either an MPW tool or as a standalone application, and
3308 it can debug through the serial port. All the usual GDB commands are
3309 available, but to the target command, you must supply "serial" as the
3310 device type instead of "/dev/ttyXX". See mpw-README in the main
3311 directory for more information on how to build. The MPW configuration
3312 scripts */mpw-config.in support only a few targets, and only the
3313 mips-idt-ecoff target has been tested.
3317 GDB configuration now uses autoconf. This is not user-visible,
3318 but does simplify configuration and building.
3322 GDB now supports hpux10.
3324 *** Changes in GDB-4.14:
3326 * New native configurations
3328 x86 FreeBSD i[345]86-*-freebsd
3329 x86 NetBSD i[345]86-*-netbsd
3330 NS32k NetBSD ns32k-*-netbsd
3331 Sparc NetBSD sparc-*-netbsd
3335 A29K VxWorks a29k-*-vxworks
3336 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3337 CPU32 EST-300 emulator m68*-*-est*
3338 PowerPC ELF powerpc-*-elf
3341 * Alpha OSF/1 support for procfs
3343 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3344 possible to attach to running processes. As the mounting of the /proc
3345 filesystem is optional on the Alpha, GDB automatically determines
3346 the availability of /proc during startup. This can lead to problems
3347 if /proc is unmounted after GDB has been started.
3349 * Arguments to user-defined commands
3351 User commands may accept up to 10 arguments separated by whitespace.
3352 Arguments are accessed within the user command via $arg0..$arg9. A
3355 print $arg0 + $arg1 + $arg2
3357 To execute the command use:
3360 Defines the command "adder" which prints the sum of its three arguments.
3361 Note the arguments are text substitutions, so they may reference variables,
3362 use complex expressions, or even perform inferior function calls.
3364 * New `if' and `while' commands
3366 This makes it possible to write more sophisticated user-defined
3367 commands. Both commands take a single argument, which is the
3368 expression to evaluate, and must be followed by the commands to
3369 execute, one per line, if the expression is nonzero, the list being
3370 terminated by the word `end'. The `if' command list may include an
3371 `else' word, which causes the following commands to be executed only
3372 if the expression is zero.
3374 * Fortran source language mode
3376 GDB now includes partial support for Fortran 77. It will recognize
3377 Fortran programs and can evaluate a subset of Fortran expressions, but
3378 variables and functions may not be handled correctly. GDB will work
3379 with G77, but does not yet know much about symbols emitted by other
3382 * Better HPUX support
3384 Most debugging facilities now work on dynamic executables for HPPAs
3385 running hpux9 or later. You can attach to running dynamically linked
3386 processes, but by default the dynamic libraries will be read-only, so
3387 for instance you won't be able to put breakpoints in them. To change
3388 that behavior do the following before running the program:
3394 This will cause the libraries to be mapped private and read-write.
3395 To revert to the normal behavior, do this:
3401 You cannot set breakpoints or examine data in the library until after
3402 the library is loaded if the function/data symbols do not have
3405 GDB can now also read debug symbols produced by the HP C compiler on
3406 HPPAs (sorry, no C++, Fortran or 68k support).
3408 * Target byte order now dynamically selectable
3410 You can choose which byte order to use with a target system, via the
3411 commands "set endian big" and "set endian little", and you can see the
3412 current setting by using "show endian". You can also give the command
3413 "set endian auto", in which case GDB will use the byte order
3414 associated with the executable. Currently, only embedded MIPS
3415 configurations support dynamic selection of target byte order.
3417 * New DOS host serial code
3419 This version uses DPMI interrupts to handle buffered I/O, so you
3420 no longer need to run asynctsr when debugging boards connected to
3423 *** Changes in GDB-4.13:
3425 * New "complete" command
3427 This lists all the possible completions for the rest of the line, if it
3428 were to be given as a command itself. This is intended for use by emacs.
3430 * Trailing space optional in prompt
3432 "set prompt" no longer adds a space for you after the prompt you set. This
3433 allows you to set a prompt which ends in a space or one that does not.
3435 * Breakpoint hit counts
3437 "info break" now displays a count of the number of times the breakpoint
3438 has been hit. This is especially useful in conjunction with "ignore"; you
3439 can ignore a large number of breakpoint hits, look at the breakpoint info
3440 to see how many times the breakpoint was hit, then run again, ignoring one
3441 less than that number, and this will get you quickly to the last hit of
3444 * Ability to stop printing at NULL character
3446 "set print null-stop" will cause GDB to stop printing the characters of
3447 an array when the first NULL is encountered. This is useful when large
3448 arrays actually contain only short strings.
3450 * Shared library breakpoints
3452 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3453 breakpoints in shared libraries before the executable is run.
3455 * Hardware watchpoints
3457 There is a new hardware breakpoint for the watch command for sparclite
3458 targets. See gdb/sparclite/hw_breakpoint.note.
3460 Hardware watchpoints are also now supported under GNU/Linux.
3464 Annotations have been added. These are for use with graphical interfaces,
3465 and are still experimental. Currently only gdba.el uses these.
3467 * Improved Irix 5 support
3469 GDB now works properly with Irix 5.2.
3471 * Improved HPPA support
3473 GDB now works properly with the latest GCC and GAS.
3475 * New native configurations
3477 Sequent PTX4 i[34]86-sequent-ptx4
3478 HPPA running OSF/1 hppa*-*-osf*
3479 Atari TT running SVR4 m68*-*-sysv4*
3480 RS/6000 LynxOS rs6000-*-lynxos*
3484 OS/9000 i[34]86-*-os9k
3485 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3488 * Hitachi SH7000 and E7000-PC ICE support
3490 There is now support for communicating with the Hitachi E7000-PC ICE.
3491 This is available automatically when GDB is configured for the SH.
3495 As usual, a variety of small fixes and improvements, both generic
3496 and configuration-specific. See the ChangeLog for more detail.
3498 *** Changes in GDB-4.12:
3500 * Irix 5 is now supported
3504 GDB-4.12 on the HPPA has a number of changes which make it unable
3505 to debug the output from the currently released versions of GCC and
3506 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3507 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3508 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3511 *** Changes in GDB-4.11:
3513 * User visible changes:
3517 The "set remotedebug" option is now consistent between the mips remote
3518 target, remote targets using the gdb-specific protocol, UDI (AMD's
3519 debug protocol for the 29k) and the 88k bug monitor. It is now an
3520 integer specifying a debug level (normally 0 or 1, but 2 means more
3521 debugging info for the mips target).
3523 * DEC Alpha native support
3525 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3526 debug info, but GDB works fairly well with the DEC compiler and should
3527 work with a future GCC release. See the README file for a few
3528 Alpha-specific notes.
3530 * Preliminary thread implementation
3532 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3534 * LynxOS native and target support for 386
3536 This release has been hosted on LynxOS 2.2, and also can be configured
3537 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3540 * Improvements in C++ mangling/demangling.
3542 This release has much better g++ debugging, specifically in name
3543 mangling/demangling, virtual function calls, print virtual table,
3544 call methods, ...etc.
3546 *** Changes in GDB-4.10:
3548 * User visible changes:
3550 Remote debugging using the GDB-specific (`target remote') protocol now
3551 supports the `load' command. This is only useful if you have some
3552 other way of getting the stub to the target system, and you can put it
3553 somewhere in memory where it won't get clobbered by the download.
3555 Filename completion now works.
3557 When run under emacs mode, the "info line" command now causes the
3558 arrow to point to the line specified. Also, "info line" prints
3559 addresses in symbolic form (as well as hex).
3561 All vxworks based targets now support a user settable option, called
3562 vxworks-timeout. This option represents the number of seconds gdb
3563 should wait for responses to rpc's. You might want to use this if
3564 your vxworks target is, perhaps, a slow software simulator or happens
3565 to be on the far side of a thin network line.
3569 This release contains support for using a DEC alpha as a GDB host for
3570 cross debugging. Native alpha debugging is not supported yet.
3573 *** Changes in GDB-4.9:
3577 This is the first GDB release which is accompanied by a matching testsuite.
3578 The testsuite requires installation of dejagnu, which should be available
3579 via ftp from most sites that carry GNU software.
3583 'Cfront' style demangling has had its name changed to 'ARM' style, to
3584 emphasize that it was written from the specifications in the C++ Annotated
3585 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3586 disclaimers, it still generated too much confusion with users attempting to
3587 use gdb with AT&T cfront.
3591 GDB now uses a standard remote interface to a simulator library.
3592 So far, the library contains simulators for the Zilog Z8001/2, the
3593 Hitachi H8/300, H8/500 and Super-H.
3595 * New targets supported
3597 H8/300 simulator h8300-hitachi-hms or h8300hms
3598 H8/500 simulator h8500-hitachi-hms or h8500hms
3599 SH simulator sh-hitachi-hms or sh
3600 Z8000 simulator z8k-zilog-none or z8ksim
3601 IDT MIPS board over serial line mips-idt-ecoff
3603 Cross-debugging to GO32 targets is supported. It requires a custom
3604 version of the i386-stub.c module which is integrated with the
3605 GO32 memory extender.
3607 * New remote protocols
3609 MIPS remote debugging protocol.
3611 * New source languages supported
3613 This version includes preliminary support for Chill, a Pascal like language
3614 used by telecommunications companies. Chill support is also being integrated
3615 into the GNU compiler, but we don't know when it will be publically available.
3618 *** Changes in GDB-4.8:
3620 * HP Precision Architecture supported
3622 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3623 version of this support was available as a set of patches from the
3624 University of Utah. GDB does not support debugging of programs
3625 compiled with the HP compiler, because HP will not document their file
3626 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3627 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3629 Many problems in the preliminary version have been fixed.
3631 * Faster and better demangling
3633 We have improved template demangling and fixed numerous bugs in the GNU style
3634 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3635 character types (wchar_t) are now supported. Demangling of each symbol is now
3636 only done once, and is cached when the symbol table for a file is read in.
3637 This results in a small increase in memory usage for C programs, a moderate
3638 increase in memory usage for C++ programs, and a fantastic speedup in
3641 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3642 from the specifications in the Annotated Reference Manual, which AT&T's
3643 compiler does not actually implement.
3645 * G++ multiple inheritance compiler problem
3647 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3648 inheritance lattices was reworked to properly discover ambiguities. We
3649 recently found an example which causes this new algorithm to fail in a
3650 very subtle way, producing bad debug information for those classes.
3651 The file 'gcc.patch' (in this directory) can be applied to gcc to
3652 circumvent the problem. A future GCC release will contain a complete
3655 The previous G++ debug info problem (mentioned below for the gdb-4.7
3656 release) is fixed in gcc version 2.3.2.
3658 * Improved configure script
3660 The `configure' script will now attempt to guess your system type if
3661 you don't supply a host system type. The old scheme of supplying a
3662 host system triplet is preferable over using this. All the magic is
3663 done in the new `config.guess' script. Examine it for details.
3665 We have also brought our configure script much more in line with the FSF's
3666 version. It now supports the --with-xxx options. In particular,
3667 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3668 The resulting GDB will not be able to read arbitrary object file formats --
3669 only the format ``expected'' to be used on the configured target system.
3670 We hope to make this the default in a future release.
3672 * Documentation improvements
3674 There's new internal documentation on how to modify GDB, and how to
3675 produce clean changes to the code. We implore people to read it
3676 before submitting changes.
3678 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3679 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3680 `info' files are also provided. To build `info' files from scratch,
3681 you will need the latest `makeinfo' release, which will be available in
3682 a future texinfo-X.Y release.
3684 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3685 We're not sure exactly which versions have this problem, but it has
3686 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3687 or better. If that isn't possible, there is a patch in
3688 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3689 around this problem.
3693 GDB now supports array constants that can be used in expressions typed in by
3694 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3695 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3698 The new directory `gdb/sparclite' contains a program that demonstrates
3699 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3701 * New native hosts supported
3703 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3704 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3706 * New targets supported
3708 AMD 29k family via UDI a29k-amd-udi or udi29k
3710 * New file formats supported
3712 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3713 HPUX core files, and SCO 3.2v2 core files.
3717 Attaching to processes now works again; thanks for the many bug reports.
3719 We have also stomped on a bunch of core dumps caused by
3720 printf_filtered("%s") problems.
3722 We eliminated a copyright problem on the rpc and ptrace header files
3723 for VxWorks, which was discovered at the last minute during the 4.7
3724 release. You should now be able to build a VxWorks GDB.
3726 You can now interrupt gdb while an attached process is running. This
3727 will cause the attached process to stop, and give control back to GDB.
3729 We fixed problems caused by using too many file descriptors
3730 for reading symbols from object files and libraries. This was
3731 especially a problem for programs that used many (~100) shared
3734 The `step' command now only enters a subroutine if there is line number
3735 information for the subroutine. Otherwise it acts like the `next'
3736 command. Previously, `step' would enter subroutines if there was
3737 any debugging information about the routine. This avoids problems
3738 when using `cc -g1' on MIPS machines.
3740 * Internal improvements
3742 GDB's internal interfaces have been improved to make it easier to support
3743 debugging of multiple languages in the future.
3745 GDB now uses a common structure for symbol information internally.
3746 Minimal symbols (derived from linkage symbols in object files), partial
3747 symbols (from a quick scan of debug information), and full symbols
3748 contain a common subset of information, making it easier to write
3749 shared code that handles any of them.
3751 * New command line options
3753 We now accept --silent as an alias for --quiet.
3757 The memory-mapped-malloc library is now licensed under the GNU Library
3758 General Public License.
3760 *** Changes in GDB-4.7:
3762 * Host/native/target split
3764 GDB has had some major internal surgery to untangle the support for
3765 hosts and remote targets. Now, when you configure GDB for a remote
3766 target, it will no longer load in all of the support for debugging
3767 local programs on the host. When fully completed and tested, this will
3768 ensure that arbitrary host/target combinations are possible.
3770 The primary conceptual shift is to separate the non-portable code in
3771 GDB into three categories. Host specific code is required any time GDB
3772 is compiled on that host, regardless of the target. Target specific
3773 code relates to the peculiarities of the target, but can be compiled on
3774 any host. Native specific code is everything else: it can only be
3775 built when the host and target are the same system. Child process
3776 handling and core file support are two common `native' examples.
3778 GDB's use of /proc for controlling Unix child processes is now cleaner.
3779 It has been split out into a single module under the `target_ops' vector,
3780 plus two native-dependent functions for each system that uses /proc.
3782 * New hosts supported
3784 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3785 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3786 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3788 * New targets supported
3790 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3791 68030 and CPU32 m68030-*-*, m68332-*-*
3793 * New native hosts supported
3795 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3796 (386bsd is not well tested yet)
3797 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3799 * New file formats supported
3801 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3802 supports reading of `a.out.adobe' object files, which are an a.out
3803 format extended with minimal information about multiple sections.
3807 `show copying' is the same as the old `info copying'.
3808 `show warranty' is the same as `info warrantee'.
3809 These were renamed for consistency. The old commands continue to work.
3811 `info handle' is a new alias for `info signals'.
3813 You can now define pre-command hooks, which attach arbitrary command
3814 scripts to any command. The commands in the hook will be executed
3815 prior to the user's command. You can also create a hook which will be
3816 executed whenever the program stops. See gdb.texinfo.
3820 We now deal with Cfront style name mangling, and can even extract type
3821 info from mangled symbols. GDB can automatically figure out which
3822 symbol mangling style your C++ compiler uses.
3824 Calling of methods and virtual functions has been improved as well.
3828 The crash that occured when debugging Sun Ansi-C compiled binaries is
3829 fixed. This was due to mishandling of the extra N_SO stabs output
3832 We also finally got Ultrix 4.2 running in house, and fixed core file
3833 support, with help from a dozen people on the net.
3835 John M. Farrell discovered that the reason that single-stepping was so
3836 slow on all of the Mips based platforms (primarily SGI and DEC) was
3837 that we were trying to demangle and lookup a symbol used for internal
3838 purposes on every instruction that was being stepped through. Changing
3839 the name of that symbol so that it couldn't be mistaken for a C++
3840 mangled symbol sped things up a great deal.
3842 Rich Pixley sped up symbol lookups in general by getting much smarter
3843 about when C++ symbol mangling is necessary. This should make symbol
3844 completion (TAB on the command line) much faster. It's not as fast as
3845 we'd like, but it's significantly faster than gdb-4.6.
3849 A new user controllable variable 'call_scratch_address' can
3850 specify the location of a scratch area to be used when GDB
3851 calls a function in the target. This is necessary because the
3852 usual method of putting the scratch area on the stack does not work
3853 in systems that have separate instruction and data spaces.
3855 We integrated changes to support the 29k UDI (Universal Debugger
3856 Interface), but discovered at the last minute that we didn't have all
3857 of the appropriate copyright paperwork. We are working with AMD to
3858 resolve this, and hope to have it available soon.
3862 We have sped up the remote serial line protocol, especially for targets
3863 with lots of registers. It now supports a new `expedited status' ('T')
3864 message which can be used in place of the existing 'S' status message.
3865 This allows the remote stub to send only the registers that GDB
3866 needs to make a quick decision about single-stepping or conditional
3867 breakpoints, eliminating the need to fetch the entire register set for
3868 each instruction being stepped through.
3870 The GDB remote serial protocol now implements a write-through cache for
3871 registers, only re-reading the registers if the target has run.
3873 There is also a new remote serial stub for SPARC processors. You can
3874 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3875 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3876 processor with a serial port.
3880 Configure.in files have become much easier to read and modify. A new
3881 `table driven' format makes it more obvious what configurations are
3882 supported, and what files each one uses.
3886 There is a new opcodes library which will eventually contain all of the
3887 disassembly routines and opcode tables. At present, it only contains
3888 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3889 disassembler (binutils/objdump) to share these routines.
3891 The libiberty library is now copylefted under the GNU Library General
3892 Public License. This allows more liberal use, and was done so libg++
3893 can use it. This makes no difference to GDB, since the Library License
3894 grants all the rights from the General Public License.
3898 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3899 reference to the stabs symbol info used by the debugger. It is (as far
3900 as we know) the only published document on this fascinating topic. We
3901 encourage you to read it, compare it to the stabs information on your
3902 system, and send improvements on the document in general (to
3903 bug-gdb@prep.ai.mit.edu).
3905 And, of course, many bugs have been fixed.
3908 *** Changes in GDB-4.6:
3910 * Better support for C++ function names
3912 GDB now accepts as input the "demangled form" of C++ overloaded function
3913 names and member function names, and can do command completion on such names
3914 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3915 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3916 Make use of command completion, it is your friend.
3918 GDB also now accepts a variety of C++ mangled symbol formats. They are
3919 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3920 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3921 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3922 for the list of formats.
3924 * G++ symbol mangling problem
3926 Recent versions of gcc have a bug in how they emit debugging information for
3927 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3928 directory) can be applied to gcc to fix the problem. Alternatively, if you
3929 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3930 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3931 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3934 * New 'maintenance' command
3936 All of the commands related to hacking GDB internals have been moved out of
3937 the main command set, and now live behind the 'maintenance' command. This
3938 can also be abbreviated as 'mt'. The following changes were made:
3940 dump-me -> maintenance dump-me
3941 info all-breakpoints -> maintenance info breakpoints
3942 printmsyms -> maintenance print msyms
3943 printobjfiles -> maintenance print objfiles
3944 printpsyms -> maintenance print psymbols
3945 printsyms -> maintenance print symbols
3947 The following commands are new:
3949 maintenance demangle Call internal GDB demangler routine to
3950 demangle a C++ link name and prints the result.
3951 maintenance print type Print a type chain for a given symbol
3953 * Change to .gdbinit file processing
3955 We now read the $HOME/.gdbinit file before processing the argv arguments
3956 (e.g. reading symbol files or core files). This allows global parameters to
3957 be set, which will apply during the symbol reading. The ./.gdbinit is still
3958 read after argv processing.
3960 * New hosts supported
3962 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3964 GNU/Linux support i386-unknown-linux or linux
3966 We are also including code to support the HP/PA running BSD and HPUX. This
3967 is almost guaranteed not to work, as we didn't have time to test or build it
3968 for this release. We are including it so that the more adventurous (or
3969 masochistic) of you can play with it. We also had major problems with the
3970 fact that the compiler that we got from HP doesn't support the -g option.
3973 * New targets supported
3975 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3977 * More smarts about finding #include files
3979 GDB now remembers the compilation directory for all include files, and for
3980 all files from which C is generated (like yacc and lex sources). This
3981 greatly improves GDB's ability to find yacc/lex sources, and include files,
3982 especially if you are debugging your program from a directory different from
3983 the one that contains your sources.
3985 We also fixed a bug which caused difficulty with listing and setting
3986 breakpoints in include files which contain C code. (In the past, you had to
3987 try twice in order to list an include file that you hadn't looked at before.)
3989 * Interesting infernals change
3991 GDB now deals with arbitrary numbers of sections, where the symbols for each
3992 section must be relocated relative to that section's landing place in the
3993 target's address space. This work was needed to support ELF with embedded
3994 stabs used by Solaris-2.0.
3996 * Bug fixes (of course!)
3998 There have been loads of fixes for the following things:
3999 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4000 i960, stabs, DOS(GO32), procfs, etc...
4002 See the ChangeLog for details.
4004 *** Changes in GDB-4.5:
4006 * New machines supported (host and target)
4008 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4010 SGI Irix-4.x mips-sgi-irix4 or iris4
4012 * New malloc package
4014 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4015 Mmalloc is capable of handling mutiple heaps of memory. It is also
4016 capable of saving a heap to a file, and then mapping it back in later.
4017 This can be used to greatly speedup the startup of GDB by using a
4018 pre-parsed symbol table which lives in a mmalloc managed heap. For
4019 more details, please read mmalloc/mmalloc.texi.
4023 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4024 'help info proc' for details.
4026 * MIPS ecoff symbol table format
4028 The code that reads MIPS symbol table format is now supported on all hosts.
4029 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4032 * File name changes for MS-DOS
4034 Many files in the config directories have been renamed to make it easier to
4035 support GDB on MS-DOSe systems (which have very restrictive file name
4036 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4037 environment) is close to working but has some remaining problems. Note
4038 that debugging of DOS programs is not supported, due to limitations
4039 in the ``operating system'', but it can be used to host cross-debugging.
4041 * Cross byte order fixes
4043 Many fixes have been made to support cross debugging of Sparc and MIPS
4044 targets from hosts whose byte order differs.
4046 * New -mapped and -readnow options
4048 If memory-mapped files are available on your system through the 'mmap'
4049 system call, you can use the -mapped option on the `file' or
4050 `symbol-file' commands to cause GDB to write the symbols from your
4051 program into a reusable file. If the program you are debugging is
4052 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4053 Future GDB debugging sessions will notice the presence of this file,
4054 and will quickly map in symbol information from it, rather than reading
4055 the symbol table from the executable program. Using the '-mapped'
4056 option in a GDB `file' or `symbol-file' command has the same effect as
4057 starting GDB with the '-mapped' command-line option.
4059 You can cause GDB to read the entire symbol table immediately by using
4060 the '-readnow' option with any of the commands that load symbol table
4061 information (or on the GDB command line). This makes the command
4062 slower, but makes future operations faster.
4064 The -mapped and -readnow options are typically combined in order to
4065 build a `fred.syms' file that contains complete symbol information.
4066 A simple GDB invocation to do nothing but build a `.syms' file for future
4069 gdb -batch -nx -mapped -readnow programname
4071 The `.syms' file is specific to the host machine on which GDB is run.
4072 It holds an exact image of GDB's internal symbol table. It cannot be
4073 shared across multiple host platforms.
4075 * longjmp() handling
4077 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4078 siglongjmp() without losing control. This feature has not yet been ported to
4079 all systems. It currently works on many 386 platforms, all MIPS-based
4080 platforms (SGI, DECstation, etc), and Sun3/4.
4084 Preliminary work has been put in to support the new Solaris OS from Sun. At
4085 this time, it can control and debug processes, but it is not capable of
4090 As always, many many bug fixes. The major areas were with g++, and mipsread.
4091 People using the MIPS-based platforms should experience fewer mysterious
4092 crashes and trashed symbol tables.
4094 *** Changes in GDB-4.4:
4096 * New machines supported (host and target)
4098 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4100 BSD Reno on Vax vax-dec-bsd
4101 Ultrix on Vax vax-dec-ultrix
4103 * New machines supported (target)
4105 AMD 29000 embedded, using EBMON a29k-none-none
4109 GDB continues to improve its handling of C++. `References' work better.
4110 The demangler has also been improved, and now deals with symbols mangled as
4111 per the Annotated C++ Reference Guide.
4113 GDB also now handles `stabs' symbol information embedded in MIPS
4114 `ecoff' symbol tables. Since the ecoff format was not easily
4115 extensible to handle new languages such as C++, this appeared to be a
4116 good way to put C++ debugging info into MIPS binaries. This option
4117 will be supported in the GNU C compiler, version 2, when it is
4120 * New features for SVR4
4122 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4123 shared libraries. Debugging dynamically linked programs should present
4124 only minor differences from debugging statically linked programs.
4126 The `info proc' command will print out information about any process
4127 on an SVR4 system (including the one you are debugging). At the moment,
4128 it prints the address mappings of the process.
4130 If you bring up GDB on another SVR4 system, please send mail to
4131 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4133 * Better dynamic linking support in SunOS
4135 Reading symbols from shared libraries which contain debugging symbols
4136 now works properly. However, there remain issues such as automatic
4137 skipping of `transfer vector' code during function calls, which
4138 make it harder to debug code in a shared library, than to debug the
4139 same code linked statically.
4143 GDB is now using the latest `getopt' routines from the FSF. This
4144 version accepts the -- prefix for options with long names. GDB will
4145 continue to accept the old forms (-option and +option) as well.
4146 Various single letter abbreviations for options have been explicity
4147 added to the option table so that they won't get overshadowed in the
4148 future by other options that begin with the same letter.
4152 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4153 Many assorted bugs have been handled. Many more remain to be handled.
4154 See the various ChangeLog files (primarily in gdb and bfd) for details.
4157 *** Changes in GDB-4.3:
4159 * New machines supported (host and target)
4161 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4162 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4163 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4165 * Almost SCO Unix support
4167 We had hoped to support:
4168 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4169 (except for core file support), but we discovered very late in the release
4170 that it has problems with process groups that render gdb unusable. Sorry
4171 about that. I encourage people to fix it and post the fixes.
4173 * Preliminary ELF and DWARF support
4175 GDB can read ELF object files on System V Release 4, and can handle
4176 debugging records for C, in DWARF format, in ELF files. This support
4177 is preliminary. If you bring up GDB on another SVR4 system, please
4178 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4183 GDB now uses the latest `readline' library. One user-visible change
4184 is that two tabs will list possible command completions, which previously
4185 required typing M-? (meta-question mark, or ESC ?).
4189 The `stepi' bug that many of you noticed has been squashed.
4190 Many bugs in C++ have been handled. Many more remain to be handled.
4191 See the various ChangeLog files (primarily in gdb and bfd) for details.
4193 * State of the MIPS world (in case you wondered):
4195 GDB can understand the symbol tables emitted by the compilers
4196 supplied by most vendors of MIPS-based machines, including DEC. These
4197 symbol tables are in a format that essentially nobody else uses.
4199 Some versions of gcc come with an assembler post-processor called
4200 mips-tfile. This program is required if you want to do source-level
4201 debugging of gcc-compiled programs. I believe FSF does not ship
4202 mips-tfile with gcc version 1, but it will eventually come with gcc
4205 Debugging of g++ output remains a problem. g++ version 1.xx does not
4206 really support it at all. (If you're lucky, you should be able to get
4207 line numbers and stack traces to work, but no parameters or local
4208 variables.) With some work it should be possible to improve the
4211 When gcc version 2 is released, you will have somewhat better luck.
4212 However, even then you will get confusing results for inheritance and
4215 We will eventually provide full debugging of g++ output on
4216 DECstations. This will probably involve some kind of stabs-in-ecoff
4217 encapulation, but the details have not been worked out yet.
4220 *** Changes in GDB-4.2:
4222 * Improved configuration
4224 Only one copy of `configure' exists now, and it is not self-modifying.
4225 Porting BFD is simpler.
4229 The `step' and `next' commands now only stop at the first instruction
4230 of a source line. This prevents the multiple stops that used to occur
4231 in switch statements, for-loops, etc. `Step' continues to stop if a
4232 function that has debugging information is called within the line.
4236 Lots of small bugs fixed. More remain.
4238 * New host supported (not target)
4240 Intel 386 PC clone running Mach i386-none-mach
4243 *** Changes in GDB-4.1:
4245 * Multiple source language support
4247 GDB now has internal scaffolding to handle several source languages.
4248 It determines the type of each source file from its filename extension,
4249 and will switch expression parsing and number formatting to match the
4250 language of the function in the currently selected stack frame.
4251 You can also specifically set the language to be used, with
4252 `set language c' or `set language modula-2'.
4256 GDB now has preliminary support for the GNU Modula-2 compiler,
4257 currently under development at the State University of New York at
4258 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4259 continue through the fall of 1991 and into 1992.
4261 Other Modula-2 compilers are currently not supported, and attempting to
4262 debug programs compiled with them will likely result in an error as the
4263 symbol table is read. Feel free to work on it, though!
4265 There are hooks in GDB for strict type checking and range checking,
4266 in the `Modula-2 philosophy', but they do not currently work.
4270 GDB can now write to executable and core files (e.g. patch
4271 a variable's value). You must turn this switch on, specify
4272 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4273 by assigning a new value to a variable. Modifications take
4276 * Automatic SunOS shared library reading
4278 When you run your program, GDB automatically determines where its
4279 shared libraries (if any) have been loaded, and reads their symbols.
4280 The `share' command is no longer needed. This also works when
4281 examining core files.
4285 You can specify the number of lines that the `list' command shows.
4288 * New machines supported (host and target)
4290 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4291 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4292 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4294 * New hosts supported (not targets)
4296 IBM RT/PC: romp-ibm-aix or rtpc
4298 * New targets supported (not hosts)
4300 AMD 29000 embedded with COFF a29k-none-coff
4301 AMD 29000 embedded with a.out a29k-none-aout
4302 Ultracomputer remote kernel debug a29k-nyu-kern
4304 * New remote interfaces
4310 *** Changes in GDB-4.0:
4314 Wide output is wrapped at good places to make the output more readable.
4316 Gdb now supports cross-debugging from a host machine of one type to a
4317 target machine of another type. Communication with the target system
4318 is over serial lines. The ``target'' command handles connecting to the
4319 remote system; the ``load'' command will download a program into the
4320 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4321 also supports debugging of realtime processes running under VxWorks,
4322 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4323 stub on the target system.
4325 New CPUs supported include the AMD 29000 and Intel 960.
4327 GDB now reads object files and symbol tables via a ``binary file''
4328 library, which allows a single copy of GDB to debug programs of multiple
4329 object file types such as a.out and coff.
4331 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4332 refcard.dvi and refcard.ps are available to format it).
4335 * Control-Variable user interface simplified
4337 All variables that control the operation of the debugger can be set
4338 by the ``set'' command, and displayed by the ``show'' command.
4340 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4341 ``Show prompt'' produces the response:
4342 Gdb's prompt is new-gdb=>.
4344 What follows are the NEW set commands. The command ``help set'' will
4345 print a complete list of old and new set commands. ``help set FOO''
4346 will give a longer description of the variable FOO. ``show'' will show
4347 all of the variable descriptions and their current settings.
4349 confirm on/off: Enables warning questions for operations that are
4350 hard to recover from, e.g. rerunning the program while
4351 it is already running. Default is ON.
4353 editing on/off: Enables EMACS style command line editing
4354 of input. Previous lines can be recalled with
4355 control-P, the current line can be edited with control-B,
4356 you can search for commands with control-R, etc.
4359 history filename NAME: NAME is where the gdb command history
4360 will be stored. The default is .gdb_history,
4361 or the value of the environment variable
4364 history size N: The size, in commands, of the command history. The
4365 default is 256, or the value of the environment variable
4368 history save on/off: If this value is set to ON, the history file will
4369 be saved after exiting gdb. If set to OFF, the
4370 file will not be saved. The default is OFF.
4372 history expansion on/off: If this value is set to ON, then csh-like
4373 history expansion will be performed on
4374 command line input. The default is OFF.
4376 radix N: Sets the default radix for input and output. It can be set
4377 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4378 in the current radix, so "set radix 10" is always a no-op.
4380 height N: This integer value is the number of lines on a page. Default
4381 is 24, the current `stty rows'' setting, or the ``li#''
4382 setting from the termcap entry matching the environment
4385 width N: This integer value is the number of characters on a line.
4386 Default is 80, the current `stty cols'' setting, or the ``co#''
4387 setting from the termcap entry matching the environment
4390 Note: ``set screensize'' is obsolete. Use ``set height'' and
4391 ``set width'' instead.
4393 print address on/off: Print memory addresses in various command displays,
4394 such as stack traces and structure values. Gdb looks
4395 more ``symbolic'' if you turn this off; it looks more
4396 ``machine level'' with it on. Default is ON.
4398 print array on/off: Prettyprint arrays. New convenient format! Default
4401 print demangle on/off: Print C++ symbols in "source" form if on,
4404 print asm-demangle on/off: Same, for assembler level printouts
4407 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4410 * Support for Epoch Environment.
4412 The epoch environment is a version of Emacs v18 with windowing. One
4413 new command, ``inspect'', is identical to ``print'', except that if you
4414 are running in the epoch environment, the value is printed in its own
4418 * Support for Shared Libraries
4420 GDB can now debug programs and core files that use SunOS shared libraries.
4421 Symbols from a shared library cannot be referenced
4422 before the shared library has been linked with the program (this
4423 happens after you type ``run'' and before the function main() is entered).
4424 At any time after this linking (including when examining core files
4425 from dynamically linked programs), gdb reads the symbols from each
4426 shared library when you type the ``sharedlibrary'' command.
4427 It can be abbreviated ``share''.
4429 sharedlibrary REGEXP: Load shared object library symbols for files
4430 matching a unix regular expression. No argument
4431 indicates to load symbols for all shared libraries.
4433 info sharedlibrary: Status of loaded shared libraries.
4438 A watchpoint stops execution of a program whenever the value of an
4439 expression changes. Checking for this slows down execution
4440 tremendously whenever you are in the scope of the expression, but is
4441 quite useful for catching tough ``bit-spreader'' or pointer misuse
4442 problems. Some machines such as the 386 have hardware for doing this
4443 more quickly, and future versions of gdb will use this hardware.
4445 watch EXP: Set a watchpoint (breakpoint) for an expression.
4447 info watchpoints: Information about your watchpoints.
4449 delete N: Deletes watchpoint number N (same as breakpoints).
4450 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4451 enable N: Re-enables watchpoint number N (same as breakpoints).
4454 * C++ multiple inheritance
4456 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4459 * C++ exception handling
4461 Gdb now supports limited C++ exception handling. Besides the existing
4462 ability to breakpoint on an exception handler, gdb can breakpoint on
4463 the raising of an exception (before the stack is peeled back to the
4466 catch FOO: If there is a FOO exception handler in the dynamic scope,
4467 set a breakpoint to catch exceptions which may be raised there.
4468 Multiple exceptions (``catch foo bar baz'') may be caught.
4470 info catch: Lists all exceptions which may be caught in the
4471 current stack frame.
4474 * Minor command changes
4476 The command ``call func (arg, arg, ...)'' now acts like the print
4477 command, except it does not print or save a value if the function's result
4478 is void. This is similar to dbx usage.
4480 The ``up'' and ``down'' commands now always print the frame they end up
4481 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4482 frames without printing.
4484 * New directory command
4486 'dir' now adds directories to the FRONT of the source search path.
4487 The path starts off empty. Source files that contain debug information
4488 about the directory in which they were compiled can be found even
4489 with an empty path; Sun CC and GCC include this information. If GDB can't
4490 find your source file in the current directory, type "dir .".
4492 * Configuring GDB for compilation
4494 For normal use, type ``./configure host''. See README or gdb.texinfo
4497 GDB now handles cross debugging. If you are remotely debugging between
4498 two different machines, type ``./configure host -target=targ''.
4499 Host is the machine where GDB will run; targ is the machine
4500 where the program that you are debugging will run.