1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.3
6 * New configure option --with-iconv-bin.
7 When using the internationalization support like the one in the GNU C
8 library, GDB will invoke the "iconv" program to get a list of supported
9 character sets. If this program lives in a non-standard location, one can
10 use this option to specify where to find it.
12 * When natively debugging programs on PowerPC BookE processors running
13 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
14 watchpoints, which specify a mask in addition to an address to watch.
15 The mask specifies that some bits of an address (the bits which are
16 reset in the mask) should be ignored when matching the address accessed
17 by the inferior against the watchpoint address. See the "PowerPC Embedded"
18 section in the user manual for more details.
20 * The new option --once causes GDBserver to stop listening for connections once
21 the first connection is made. The listening port used by GDBserver will
22 become available after that.
26 watch EXPRESSION mask MASK_VALUE
27 The watch command now supports the mask argument which allows creation
28 of masked watchpoints, if the current architecture supports this feature.
30 *** Changes in GDB 7.3
32 * GDB has a new command: "thread find [REGEXP]".
33 It finds the thread id whose name, target id, or thread extra info
34 matches the given regular expression.
36 * The "catch syscall" command now works on mips*-linux* targets.
38 * The -data-disassemble MI command now supports modes 2 and 3 for
39 dumping the instruction opcodes.
41 * New command line options
43 -data-directory DIR Specify DIR as the "data-directory".
44 This is mostly for testing purposes.
46 * The "maint set python auto-load on|off" command has been renamed to
47 "set auto-load-scripts on|off".
49 * GDB has a new command: "set directories".
50 It is like the "dir" command except that it replaces the
51 source path list instead of augmenting it.
53 * GDB now understands thread names.
55 On GNU/Linux, "info threads" will display the thread name as set by
56 prctl or pthread_setname_np.
58 There is also a new command, "thread name", which can be used to
59 assign a name internally for GDB to display.
62 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
63 has been integrated into GDB.
67 ** The function gdb.Write now accepts an optional keyword 'stream'.
68 This keyword, when provided, will direct the output to either
69 stdout, stderr, or GDB's logging output.
71 ** Parameters can now be be sub-classed in Python, and in particular
72 you may implement the get_set_doc and get_show_doc functions.
73 This improves how Parameter set/show documentation is processed
74 and allows for more dynamic content.
76 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
77 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
78 have an is_valid method.
80 ** Breakpoints can now be sub-classed in Python, and in particular
81 you may implement a 'stop' function that is executed each time
82 the inferior reaches that breakpoint.
84 ** New function gdb.lookup_global_symbol looks up a global symbol.
86 ** GDB values in Python are now callable if the value represents a
87 function. For example, if 'some_value' represents a function that
88 takes two integer parameters and returns a value, you can call
89 that function like so:
91 result = some_value (10,20)
93 ** Module gdb.types has been added.
94 It contains a collection of utilities for working with gdb.Types objects:
95 get_basic_type, has_field, make_enum_dict.
97 ** Module gdb.printing has been added.
98 It contains utilities for writing and registering pretty-printers.
99 New classes: PrettyPrinter, SubPrettyPrinter,
100 RegexpCollectionPrettyPrinter.
101 New function: register_pretty_printer.
103 ** New commands "info pretty-printers", "enable pretty-printer" and
104 "disable pretty-printer" have been added.
106 ** gdb.parameter("directories") is now available.
108 ** New function gdb.newest_frame returns the newest frame in the
111 ** The gdb.InferiorThread class has a new "name" attribute. This
112 holds the thread's name.
114 ** Python Support for Inferior events.
115 Python scripts can add observers to be notified of events
116 occurring in the process being debugged.
117 The following events are currently supported:
118 - gdb.events.cont Continue event.
119 - gdb.events.exited Inferior exited event.
120 - gdb.events.stop Signal received, and Breakpoint hit events.
124 ** GDB now puts template parameters in scope when debugging in an
125 instantiation. For example, if you have:
127 template<int X> int func (void) { return X; }
129 then if you step into func<5>, "print X" will show "5". This
130 feature requires proper debuginfo support from the compiler; it
131 was added to GCC 4.5.
133 ** The motion commands "next", "finish", "until", and "advance" now
134 work better when exceptions are thrown. In particular, GDB will
135 no longer lose control of the inferior; instead, the GDB will
136 stop the inferior at the point at which the exception is caught.
137 This functionality requires a change in the exception handling
138 code that was introduced in GCC 4.5.
140 * GDB now follows GCC's rules on accessing volatile objects when
141 reading or writing target state during expression evaluation.
142 One notable difference to prior behavior is that "print x = 0"
143 no longer generates a read of x; the value of the assignment is
144 now always taken directly from the value being assigned.
146 * GDB now has some support for using labels in the program's source in
147 linespecs. For instance, you can use "advance label" to continue
148 execution to a label.
150 * GDB now has support for reading and writing a new .gdb_index
151 section. This section holds a fast index of DWARF debugging
152 information and can be used to greatly speed up GDB startup and
153 operation. See the documentation for `save gdb-index' for details.
155 * The "watch" command now accepts an optional "-location" argument.
156 When used, this causes GDB to watch the memory referred to by the
157 expression. Such a watchpoint is never deleted due to it going out
160 * GDB now supports thread debugging of core dumps on GNU/Linux.
162 GDB now activates thread debugging using the libthread_db library
163 when debugging GNU/Linux core dumps, similarly to when debugging
164 live processes. As a result, when debugging a core dump file, GDB
165 is now able to display pthread_t ids of threads. For example, "info
166 threads" shows the same output as when debugging the process when it
167 was live. In earlier releases, you'd see something like this:
170 * 1 LWP 6780 main () at main.c:10
172 While now you see this:
175 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
177 It is also now possible to inspect TLS variables when debugging core
180 When debugging a core dump generated on a machine other than the one
181 used to run GDB, you may need to point GDB at the correct
182 libthread_db library with the "set libthread-db-search-path"
183 command. See the user manual for more details on this command.
185 * When natively debugging programs on PowerPC BookE processors running
186 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
187 which stop execution of the inferior whenever it executes an instruction
188 at any address within the specified range. See the "PowerPC Embedded"
189 section in the user manual for more details.
191 * New features in the GDB remote stub, GDBserver
193 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
194 and i686 LynxOS (version 5.x).
196 ** GDBserver is now supported on Blackfin Linux.
198 * New native configurations
200 ia64 HP-UX ia64-*-hpux*
204 Analog Devices, Inc. Blackfin Processor bfin-*
206 * Ada task switching is now supported on sparc-elf targets when
207 debugging a program using the Ravenscar Profile. For more information,
208 see the "Tasking Support when using the Ravenscar Profile" section
209 in the GDB user manual.
211 * Guile support was removed.
213 * New features in the GNU simulator
215 ** The --map-info flag lists all known core mappings.
217 ** CFI flashes may be simulated via the "cfi" device.
219 *** Changes in GDB 7.2
221 * Shared library support for remote targets by default
223 When GDB is configured for a generic, non-OS specific target, like
224 for example, --target=arm-eabi or one of the many *-*-elf targets,
225 GDB now queries remote stubs for loaded shared libraries using the
226 `qXfer:libraries:read' packet. Previously, shared library support
227 was always disabled for such configurations.
231 ** Argument Dependent Lookup (ADL)
233 In C++ ADL lookup directs function search to the namespaces of its
234 arguments even if the namespace has not been imported.
244 Here the compiler will search for `foo' in the namespace of 'b'
245 and find A::foo. GDB now supports this. This construct is commonly
246 used in the Standard Template Library for operators.
248 ** Improved User Defined Operator Support
250 In addition to member operators, GDB now supports lookup of operators
251 defined in a namespace and imported with a `using' directive, operators
252 defined in the global scope, operators imported implicitly from an
253 anonymous namespace, and the ADL operators mentioned in the previous
255 GDB now also supports proper overload resolution for all the previously
256 mentioned flavors of operators.
258 ** static const class members
260 Printing of static const class members that are initialized in the
261 class definition has been fixed.
263 * Windows Thread Information Block access.
265 On Windows targets, GDB now supports displaying the Windows Thread
266 Information Block (TIB) structure. This structure is visible either
267 by using the new command `info w32 thread-information-block' or, by
268 dereferencing the new convenience variable named `$_tlb', a
269 thread-specific pointer to the TIB. This feature is also supported
270 when remote debugging using GDBserver.
274 Static tracepoints are calls in the user program into a tracing
275 library. One such library is a port of the LTTng kernel tracer to
276 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
277 When debugging with GDBserver, GDB now supports combining the GDB
278 tracepoint machinery with such libraries. For example: the user can
279 use GDB to probe a static tracepoint marker (a call from the user
280 program into the tracing library) with the new "strace" command (see
281 "New commands" below). This creates a "static tracepoint" in the
282 breakpoint list, that can be manipulated with the same feature set
283 as fast and regular tracepoints. E.g., collect registers, local and
284 global variables, collect trace state variables, and define
285 tracepoint conditions. In addition, the user can collect extra
286 static tracepoint marker specific data, by collecting the new
287 $_sdata internal variable. When analyzing the trace buffer, you can
288 inspect $_sdata like any other variable available to GDB. For more
289 information, see the "Tracepoints" chapter in GDB user manual. New
290 remote packets have been defined to support static tracepoints, see
291 the "New remote packets" section below.
293 * Better reconstruction of tracepoints after disconnected tracing
295 GDB will attempt to download the original source form of tracepoint
296 definitions when starting a trace run, and then will upload these
297 upon reconnection to the target, resulting in a more accurate
298 reconstruction of the tracepoints that are in use on the target.
302 You can now exercise direct control over the ways that GDB can
303 affect your program. For instance, you can disallow the setting of
304 breakpoints, so that the program can run continuously (assuming
305 non-stop mode). In addition, the "observer" variable is available
306 to switch all of the different controls; in observer mode, GDB
307 cannot affect the target's behavior at all, which is useful for
308 tasks like diagnosing live systems in the field.
310 * The new convenience variable $_thread holds the number of the
317 Return the address of the Windows Thread Information Block of a given thread.
321 In response to several of the tracepoint packets, the target may now
322 also respond with a number of intermediate `qRelocInsn' request
323 packets before the final result packet, to have GDB handle
324 relocating an instruction to execute at a different address. This
325 is particularly useful for stubs that support fast tracepoints. GDB
326 reports support for this feature in the qSupported packet.
330 List static tracepoint markers in the target program.
334 List static tracepoint markers at a given address in the target
337 qXfer:statictrace:read
339 Read the static trace data collected (by a `collect $_sdata'
340 tracepoint action). The remote stub reports support for this packet
341 to gdb's qSupported query.
345 Send the current settings of GDB's permission flags.
349 Send part of the source (textual) form of a tracepoint definition,
350 which includes location, conditional, and action list.
352 * The source command now accepts a -s option to force searching for the
353 script in the source search path even if the script name specifies
356 * New features in the GDB remote stub, GDBserver
358 - GDBserver now support tracepoints (including fast tracepoints, and
359 static tracepoints). The feature is currently supported by the
360 i386-linux and amd64-linux builds. See the "Tracepoints support
361 in gdbserver" section in the manual for more information.
363 GDBserver JIT compiles the tracepoint's conditional agent
364 expression bytecode into native code whenever possible for low
365 overhead dynamic tracepoints conditionals. For such tracepoints,
366 an expression that examines program state is evaluated when the
367 tracepoint is reached, in order to determine whether to capture
368 trace data. If the condition is simple and false, processing the
369 tracepoint finishes very quickly and no data is gathered.
371 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
372 for static tracepoints support.
374 - GDBserver now supports x86_64 Windows 64-bit debugging.
376 * GDB now sends xmlRegisters= in qSupported packet to indicate that
377 it understands register description.
379 * The --batch flag now disables pagination and queries.
381 * X86 general purpose registers
383 GDB now supports reading/writing byte, word and double-word x86
384 general purpose registers directly. This means you can use, say,
385 $ah or $ax to refer, respectively, to the byte register AH and
386 16-bit word register AX that are actually portions of the 32-bit
387 register EAX or 64-bit register RAX.
389 * The `commands' command now accepts a range of breakpoints to modify.
390 A plain `commands' following a command that creates multiple
391 breakpoints affects all the breakpoints set by that command. This
392 applies to breakpoints set by `rbreak', and also applies when a
393 single `break' command creates multiple breakpoints (e.g.,
394 breakpoints on overloaded c++ functions).
396 * The `rbreak' command now accepts a filename specification as part of
397 its argument, limiting the functions selected by the regex to those
398 in the specified file.
400 * Support for remote debugging Windows and SymbianOS shared libraries
401 from Unix hosts has been improved. Non Windows GDB builds now can
402 understand target reported file names that follow MS-DOS based file
403 system semantics, such as file names that include drive letters and
404 use the backslash character as directory separator. This makes it
405 possible to transparently use the "set sysroot" and "set
406 solib-search-path" on Unix hosts to point as host copies of the
407 target's shared libraries. See the new command "set
408 target-file-system-kind" described below, and the "Commands to
409 specify files" section in the user manual for more information.
413 eval template, expressions...
414 Convert the values of one or more expressions under the control
415 of the string template to a command line, and call it.
417 set target-file-system-kind unix|dos-based|auto
418 show target-file-system-kind
419 Set or show the assumed file system kind for target reported file
422 save breakpoints <filename>
423 Save all current breakpoint definitions to a file suitable for use
424 in a later debugging session. To read the saved breakpoint
425 definitions, use the `source' command.
427 `save tracepoints' is a new alias for `save-tracepoints'. The latter
430 info static-tracepoint-markers
431 Display information about static tracepoint markers in the target.
433 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
434 Define a static tracepoint by probing a marker at the given
435 function, line, address, or marker ID.
439 Enable and disable observer mode.
441 set may-write-registers on|off
442 set may-write-memory on|off
443 set may-insert-breakpoints on|off
444 set may-insert-tracepoints on|off
445 set may-insert-fast-tracepoints on|off
446 set may-interrupt on|off
447 Set individual permissions for GDB effects on the target. Note that
448 some of these settings can have undesirable or surprising
449 consequences, particularly when changed in the middle of a session.
450 For instance, disabling the writing of memory can prevent
451 breakpoints from being inserted, cause single-stepping to fail, or
452 even crash your program, if you disable after breakpoints have been
453 inserted. However, GDB should not crash.
455 set record memory-query on|off
456 show record memory-query
457 Control whether to stop the inferior if memory changes caused
458 by an instruction cannot be recorded.
463 The disassemble command now supports "start,+length" form of two arguments.
467 ** GDB now provides a new directory location, called the python directory,
468 where Python scripts written for GDB can be installed. The location
469 of that directory is <data-directory>/python, where <data-directory>
470 is the GDB data directory. For more details, see section `Scripting
471 GDB using Python' in the manual.
473 ** The GDB Python API now has access to breakpoints, symbols, symbol
474 tables, program spaces, inferiors, threads and frame's code blocks.
475 Additionally, GDB Parameters can now be created from the API, and
476 manipulated via set/show in the CLI.
478 ** New functions gdb.target_charset, gdb.target_wide_charset,
479 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
481 ** New exception gdb.GdbError.
483 ** Pretty-printers are now also looked up in the current program space.
485 ** Pretty-printers can now be individually enabled and disabled.
487 ** GDB now looks for names of Python scripts to auto-load in a
488 special section named `.debug_gdb_scripts', in addition to looking
489 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
491 * Tracepoint actions were unified with breakpoint commands. In particular,
492 there are no longer differences in "info break" output for breakpoints and
493 tracepoints and the "commands" command can be used for both tracepoints and
498 ARM Symbian arm*-*-symbianelf*
500 * D language support.
501 GDB now supports debugging programs written in the D programming
504 * GDB now supports the extended ptrace interface for PowerPC which is
505 available since Linux kernel version 2.6.34. This automatically enables
506 any hardware breakpoints and additional hardware watchpoints available in
507 the processor. The old ptrace interface exposes just one hardware
508 watchpoint and no hardware breakpoints.
510 * GDB is now able to use the Data Value Compare (DVC) register available on
511 embedded PowerPC processors to implement in hardware simple watchpoint
512 conditions of the form:
514 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
516 This works in native GDB running on Linux kernels with the extended ptrace
517 interface mentioned above.
519 *** Changes in GDB 7.1
525 GDB now supports importing of namespaces in C++. This enables the
526 user to inspect variables from imported namespaces. Support for
527 namepace aliasing has also been added. So, if a namespace is
528 aliased in the current scope (e.g. namepace C=A; ) the user can
529 print variables using the alias (e.g. (gdb) print C::x).
533 All known bugs relating to the printing of virtual base class were
534 fixed. It is now possible to call overloaded static methods using a
539 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
540 and reinterpret_cast<> are now handled by the C++ expression parser.
544 Xilinx MicroBlaze microblaze-*-*
549 Xilinx MicroBlaze microblaze
552 * Multi-program debugging.
554 GDB now has support for multi-program (a.k.a. multi-executable or
555 multi-exec) debugging. This allows for debugging multiple inferiors
556 simultaneously each running a different program under the same GDB
557 session. See "Debugging Multiple Inferiors and Programs" in the
558 manual for more information. This implied some user visible changes
559 in the multi-inferior support. For example, "info inferiors" now
560 lists inferiors that are not running yet or that have exited
561 already. See also "New commands" and "New options" below.
563 * New tracing features
565 GDB's tracepoint facility now includes several new features:
567 ** Trace state variables
569 GDB tracepoints now include support for trace state variables, which
570 are variables managed by the target agent during a tracing
571 experiment. They are useful for tracepoints that trigger each
572 other, so for instance one tracepoint can count hits in a variable,
573 and then a second tracepoint has a condition that is true when the
574 count reaches a particular value. Trace state variables share the
575 $-syntax of GDB convenience variables, and can appear in both
576 tracepoint actions and condition expressions. Use the "tvariable"
577 command to create, and "info tvariables" to view; see "Trace State
578 Variables" in the manual for more detail.
582 GDB now includes an option for defining fast tracepoints, which
583 targets may implement more efficiently, such as by installing a jump
584 into the target agent rather than a trap instruction. The resulting
585 speedup can be by two orders of magnitude or more, although the
586 tradeoff is that some program locations on some target architectures
587 might not allow fast tracepoint installation, for instance if the
588 instruction to be replaced is shorter than the jump. To request a
589 fast tracepoint, use the "ftrace" command, with syntax identical to
590 the regular trace command.
592 ** Disconnected tracing
594 It is now possible to detach GDB from the target while it is running
595 a trace experiment, then reconnect later to see how the experiment
596 is going. In addition, a new variable disconnected-tracing lets you
597 tell the target agent whether to continue running a trace if the
598 connection is lost unexpectedly.
602 GDB now has the ability to save the trace buffer into a file, and
603 then use that file as a target, similarly to you can do with
604 corefiles. You can select trace frames, print data that was
605 collected in them, and use tstatus to display the state of the
606 tracing run at the moment that it was saved. To create a trace
607 file, use "tsave <filename>", and to use it, do "target tfile
610 ** Circular trace buffer
612 You can ask the target agent to handle the trace buffer as a
613 circular buffer, discarding the oldest trace frames to make room for
614 newer ones, by setting circular-trace-buffer to on. This feature may
615 not be available for all target agents.
620 The disassemble command, when invoked with two arguments, now requires
621 the arguments to be comma-separated.
624 The info variables command now displays variable definitions. Files
625 which only declare a variable are not shown.
628 The source command is now capable of sourcing Python scripts.
629 This feature is dependent on the debugger being build with Python
632 Related to this enhancement is also the introduction of a new command
633 "set script-extension" (see below).
635 * New commands (for set/show, see "New options" below)
637 record save [<FILENAME>]
638 Save a file (in core file format) containing the process record
639 execution log for replay debugging at a later time.
641 record restore <FILENAME>
642 Restore the process record execution log that was saved at an
643 earlier time, for replay debugging.
645 add-inferior [-copies <N>] [-exec <FILENAME>]
648 clone-inferior [-copies <N>] [ID]
649 Make a new inferior ready to execute the same program another
655 maint info program-spaces
656 List the program spaces loaded into GDB.
658 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
659 show remote interrupt-sequence
660 Allow the user to select one of ^C, a BREAK signal or BREAK-g
661 as the sequence to the remote target in order to interrupt the execution.
662 Ctrl-C is a default. Some system prefers BREAK which is high level of
663 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
664 Magic SysRq g. It is BREAK signal and character 'g'.
666 set remote interrupt-on-connect [on | off]
667 show remote interrupt-on-connect
668 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
669 remote target when gdb connects to it. This is needed when you debug
672 set remotebreak [on | off]
674 Deprecated. Use "set/show remote interrupt-sequence" instead.
676 tvariable $NAME [ = EXP ]
677 Create or modify a trace state variable.
680 List trace state variables and their values.
682 delete tvariable $NAME ...
683 Delete one or more trace state variables.
686 Evaluate the given expressions without collecting anything into the
687 trace buffer. (Valid in tracepoint actions only.)
689 ftrace FN / FILE:LINE / *ADDR
690 Define a fast tracepoint at the given function, line, or address.
692 * New expression syntax
694 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
695 GDB now parses 0b101010 identically with 42.
699 set follow-exec-mode new|same
700 show follow-exec-mode
701 Control whether GDB reuses the same inferior across an exec call or
702 creates a new one. This is useful to be able to restart the old
703 executable after the inferior having done an exec call.
705 set default-collect EXPR, ...
707 Define a list of expressions to be collected at each tracepoint.
708 This is a useful way to ensure essential items are not overlooked,
709 such as registers or a critical global variable.
711 set disconnected-tracing
712 show disconnected-tracing
713 If set to 1, the target is instructed to continue tracing if it
714 loses its connection to GDB. If 0, the target is to stop tracing
717 set circular-trace-buffer
718 show circular-trace-buffer
719 If set to on, the target is instructed to use a circular trace buffer
720 and discard the oldest trace frames instead of stopping the trace due
721 to a full trace buffer. If set to off, the trace stops when the buffer
722 fills up. Some targets may not support this.
724 set script-extension off|soft|strict
725 show script-extension
726 If set to "off", the debugger does not perform any script language
727 recognition, and all sourced files are assumed to be GDB scripts.
728 If set to "soft" (the default), files are sourced according to
729 filename extension, falling back to GDB scripts if the first
731 If set to "strict", files are sourced according to filename extension.
733 set ada trust-PAD-over-XVS on|off
734 show ada trust-PAD-over-XVS
735 If off, activate a workaround against a bug in the debugging information
736 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
737 the GCC sources for more information about the GNAT encoding and
738 PAD types in particular). It is always safe to set this option to
739 off, but this introduces a slight performance penalty. The default
742 * Python API Improvements
744 ** GDB provides the new class gdb.LazyString. This is useful in
745 some pretty-printing cases. The new method gdb.Value.lazy_string
746 provides a simple way to create objects of this type.
748 ** The fields returned by gdb.Type.fields now have an
749 `is_base_class' attribute.
751 ** The new method gdb.Type.range returns the range of an array type.
753 ** The new method gdb.parse_and_eval can be used to parse and
754 evaluate an expression.
759 Define a trace state variable.
762 Get the current value of a trace state variable.
765 Set desired tracing behavior upon disconnection.
768 Set the trace buffer to be linear or circular.
771 Get data about the tracepoints currently in use.
775 Process record now works correctly with hardware watchpoints.
777 Multiple bug fixes have been made to the mips-irix port, making it
778 much more reliable. In particular:
779 - Debugging threaded applications is now possible again. Previously,
780 GDB would hang while starting the program, or while waiting for
781 the program to stop at a breakpoint.
782 - Attaching to a running process no longer hangs.
783 - An error occurring while loading a core file has been fixed.
784 - Changing the value of the PC register now works again. This fixes
785 problems observed when using the "jump" command, or when calling
786 a function from GDB, or even when assigning a new value to $pc.
787 - With the "finish" and "return" commands, the return value for functions
788 returning a small array is now correctly printed.
789 - It is now possible to break on shared library code which gets executed
790 during a shared library init phase (code executed while executing
791 their .init section). Previously, the breakpoint would have no effect.
792 - GDB is now able to backtrace through the signal handler for
793 non-threaded programs.
795 PIE (Position Independent Executable) programs debugging is now supported.
796 This includes debugging execution of PIC (Position Independent Code) shared
797 libraries although for that, it should be possible to run such libraries as an
800 *** Changes in GDB 7.0
802 * GDB now has an interface for JIT compilation. Applications that
803 dynamically generate code can create symbol files in memory and register
804 them with GDB. For users, the feature should work transparently, and
805 for JIT developers, the interface is documented in the GDB manual in the
806 "JIT Compilation Interface" chapter.
808 * Tracepoints may now be conditional. The syntax is as for
809 breakpoints; either an "if" clause appended to the "trace" command,
810 or the "condition" command is available. GDB sends the condition to
811 the target for evaluation using the same bytecode format as is used
812 for tracepoint actions.
814 * The disassemble command now supports: an optional /r modifier, print the
815 raw instructions in hex as well as in symbolic form, and an optional /m
816 modifier to print mixed source+assembly.
818 * Process record and replay
820 In a architecture environment that supports ``process record and
821 replay'', ``process record and replay'' target can record a log of
822 the process execution, and replay it with both forward and reverse
825 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
826 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
827 set execution-direction {forward|reverse}, for targets that support
830 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
831 feature is available with a native GDB running on kernel version
834 * GDB now has support for multi-byte and wide character sets on the
835 target. Strings whose character type is wchar_t, char16_t, or
836 char32_t are now correctly printed. GDB supports wide- and unicode-
837 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
838 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
839 `printf'. This feature requires iconv to work properly; if your
840 system does not have a working iconv, GDB can use GNU libiconv. See
841 the installation instructions for more information.
843 * GDB now supports automatic retrieval of shared library files from
844 remote targets. To use this feature, specify a system root that begins
845 with the `remote:' prefix, either via the `set sysroot' command or via
846 the `--with-sysroot' configure-time option.
848 * "info sharedlibrary" now takes an optional regex of libraries to show,
849 and it now reports if a shared library has no debugging information.
851 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
852 now complete on file names.
854 * When completing in expressions, gdb will attempt to limit
855 completions to allowable structure or union fields, where appropriate.
856 For instance, consider:
858 # struct example { int f1; double f2; };
859 # struct example variable;
862 If the user types TAB at the end of this command line, the available
863 completions will be "f1" and "f2".
865 * Inlined functions are now supported. They show up in backtraces, and
866 the "step", "next", and "finish" commands handle them automatically.
868 * GDB now supports the token-splicing (##) and stringification (#)
869 operators when expanding macros. It also supports variable-arity
872 * GDB now supports inspecting extra signal information, exported by
873 the new $_siginfo convenience variable. The feature is currently
874 implemented on linux ARM, i386 and amd64.
876 * GDB can now display the VFP floating point registers and NEON vector
877 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
878 can provide these registers (requires Linux 2.6.30 or later). Remote
879 and simulator targets may also provide them.
884 Search memory for a sequence of bytes.
887 Turn off `+'/`-' protocol acknowledgments to permit more efficient
888 operation over reliable transport links. Use of this packet is
889 controlled by the `set remote noack-packet' command.
892 Kill the process with the specified process ID. Use this in preference
893 to `k' when multiprocess protocol extensions are supported.
896 Obtains additional operating system information
900 Read or write additional signal information.
902 * Removed remote protocol undocumented extension
904 An undocumented extension to the remote protocol's `S' stop reply
905 packet that permited the stub to pass a process id was removed.
906 Remote servers should use the `T' stop reply packet instead.
908 * GDB now supports multiple function calling conventions according to the
909 DWARF-2 DW_AT_calling_convention function attribute.
911 * The SH target utilizes the aforementioned change to distinguish between gcc
912 and Renesas calling convention. It also adds the new CLI commands
913 `set/show sh calling-convention'.
915 * GDB can now read compressed debug sections, as produced by GNU gold
916 with the --compress-debug-sections=zlib flag.
918 * 64-bit core files are now supported on AIX.
920 * Thread switching is now supported on Tru64.
922 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
923 which will be allocated using malloc later in program execution.
925 * The qXfer:libraries:read remote procotol packet now allows passing a
926 list of section offsets.
928 * On GNU/Linux, GDB can now attach to stopped processes. Several race
929 conditions handling signals delivered during attach or thread creation
930 have also been fixed.
932 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
933 From the user's standpoint, all unqualified instances of True and False
934 are treated as the standard definitions, regardless of context.
936 * GDB now parses C++ symbol and type names more flexibly. For
939 template<typename T> class C { };
942 GDB will now correctly handle all of:
944 ptype C<char const *>
946 ptype C<const char *>
949 * New features in the GDB remote stub, gdbserver
951 - The "--wrapper" command-line argument tells gdbserver to use a
952 wrapper program to launch programs for debugging.
954 - On PowerPC and S/390 targets, it is now possible to use a single
955 gdbserver executable to debug both 32-bit and 64-bit programs.
956 (This requires gdbserver itself to be built as a 64-bit executable.)
958 - gdbserver uses the new noack protocol mode for TCP connections to
959 reduce communications latency, if also supported and enabled in GDB.
961 - Support for the sparc64-linux-gnu target is now included in
964 - The amd64-linux build of gdbserver now supports debugging both
965 32-bit and 64-bit programs.
967 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
968 now support hardware watchpoints, and will use them automatically
973 GDB now has support for scripting using Python. Whether this is
974 available is determined at configure time.
976 New GDB commands can now be written in Python.
978 * Ada tasking support
980 Ada tasks can now be inspected in GDB. The following commands have
984 Print the list of Ada tasks.
986 Print detailed information about task number N.
988 Print the task number of the current task.
990 Switch the context of debugging to task number N.
992 * Support for user-defined prefixed commands. The "define" command can
993 add new commands to existing prefixes, e.g. "target".
995 * Multi-inferior, multi-process debugging.
997 GDB now has generalized support for multi-inferior debugging. See
998 "Debugging Multiple Inferiors" in the manual for more information.
999 Although availability still depends on target support, the command
1000 set is more uniform now. The GNU/Linux specific multi-forks support
1001 has been migrated to this new framework. This implied some user
1002 visible changes; see "New commands" and also "Removed commands"
1005 * Target descriptions can now describe the target OS ABI. See the
1006 "Target Description Format" section in the user manual for more
1009 * Target descriptions can now describe "compatible" architectures
1010 to indicate that the target can execute applications for a different
1011 architecture in addition to those for the main target architecture.
1012 See the "Target Description Format" section in the user manual for
1015 * Multi-architecture debugging.
1017 GDB now includes general supports for debugging applications on
1018 hybrid systems that use more than one single processor architecture
1019 at the same time. Each such hybrid architecture still requires
1020 specific support to be added. The only hybrid architecture supported
1021 in this version of GDB is the Cell Broadband Engine.
1023 * GDB now supports integrated debugging of Cell/B.E. applications that
1024 use both the PPU and SPU architectures. To enable support for hybrid
1025 Cell/B.E. debugging, you need to configure GDB to support both the
1026 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1027 --enable-targets configure option.
1029 * Non-stop mode debugging.
1031 For some targets, GDB now supports an optional mode of operation in
1032 which you can examine stopped threads while other threads continue
1033 to execute freely. This is referred to as non-stop mode, with the
1034 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1035 section in the user manual for more information.
1037 To be able to support remote non-stop debugging, a remote stub needs
1038 to implement the non-stop mode remote protocol extensions, as
1039 described in the "Remote Non-Stop" section of the user manual. The
1040 GDB remote stub, gdbserver, has been adjusted to support these
1041 extensions on linux targets.
1043 * New commands (for set/show, see "New options" below)
1045 catch syscall [NAME(S) | NUMBER(S)]
1046 Catch system calls. Arguments, which should be names of system
1047 calls or their numbers, mean catch only those syscalls. Without
1048 arguments, every syscall will be caught. When the inferior issues
1049 any of the specified syscalls, GDB will stop and announce the system
1050 call, both when it is called and when its call returns. This
1051 feature is currently available with a native GDB running on the
1052 Linux Kernel, under the following architectures: x86, x86_64,
1053 PowerPC and PowerPC64.
1055 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1057 Search memory for a sequence of bytes.
1059 maint set python print-stack
1060 maint show python print-stack
1061 Show a stack trace when an error is encountered in a Python script.
1064 Invoke CODE by passing it to the Python interpreter.
1069 These allow macros to be defined, undefined, and listed
1073 Show operating system information about processes.
1076 List the inferiors currently under GDB's control.
1079 Switch focus to inferior number NUM.
1082 Detach from inferior number NUM.
1085 Kill inferior number NUM.
1089 set spu stop-on-load
1090 show spu stop-on-load
1091 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1093 set spu auto-flush-cache
1094 show spu auto-flush-cache
1095 Control whether to automatically flush the software-managed cache
1096 during Cell/B.E. debugging.
1098 set sh calling-convention
1099 show sh calling-convention
1100 Control the calling convention used when calling SH target functions.
1103 show debug timestamp
1104 Control display of timestamps with GDB debugging output.
1106 set disassemble-next-line
1107 show disassemble-next-line
1108 Control display of disassembled source lines or instructions when
1111 set remote noack-packet
1112 show remote noack-packet
1113 Set/show the use of remote protocol QStartNoAckMode packet. See above
1114 under "New remote packets."
1116 set remote query-attached-packet
1117 show remote query-attached-packet
1118 Control use of remote protocol `qAttached' (query-attached) packet.
1120 set remote read-siginfo-object
1121 show remote read-siginfo-object
1122 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1125 set remote write-siginfo-object
1126 show remote write-siginfo-object
1127 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1130 set remote reverse-continue
1131 show remote reverse-continue
1132 Control use of remote protocol 'bc' (reverse-continue) packet.
1134 set remote reverse-step
1135 show remote reverse-step
1136 Control use of remote protocol 'bs' (reverse-step) packet.
1138 set displaced-stepping
1139 show displaced-stepping
1140 Control displaced stepping mode. Displaced stepping is a way to
1141 single-step over breakpoints without removing them from the debuggee.
1142 Also known as "out-of-line single-stepping".
1145 show debug displaced
1146 Control display of debugging info for displaced stepping.
1148 maint set internal-error
1149 maint show internal-error
1150 Control what GDB does when an internal error is detected.
1152 maint set internal-warning
1153 maint show internal-warning
1154 Control what GDB does when an internal warning is detected.
1159 Use a wrapper program to launch programs for debugging.
1161 set multiple-symbols (all|ask|cancel)
1162 show multiple-symbols
1163 The value of this variable can be changed to adjust the debugger behavior
1164 when an expression or a breakpoint location contains an ambiguous symbol
1165 name (an overloaded function name, for instance).
1167 set breakpoint always-inserted
1168 show breakpoint always-inserted
1169 Keep breakpoints always inserted in the target, as opposed to inserting
1170 them when resuming the target, and removing them when the target stops.
1171 This option can improve debugger performance on slow remote targets.
1173 set arm fallback-mode (arm|thumb|auto)
1174 show arm fallback-mode
1175 set arm force-mode (arm|thumb|auto)
1177 These commands control how ARM GDB determines whether instructions
1178 are ARM or Thumb. The default for both settings is auto, which uses
1179 the current CPSR value for instructions without symbols; previous
1180 versions of GDB behaved as if "set arm fallback-mode arm".
1182 set disable-randomization
1183 show disable-randomization
1184 Standalone programs run with the virtual address space randomization enabled
1185 by default on some platforms. This option keeps the addresses stable across
1186 multiple debugging sessions.
1190 Control whether other threads are stopped or not when some thread hits
1195 Requests that asynchronous execution is enabled in the target, if available.
1196 In this case, it's possible to resume target in the background, and interact
1197 with GDB while the target is running. "show target-async" displays the
1198 current state of asynchronous execution of the target.
1200 set target-wide-charset
1201 show target-wide-charset
1202 The target-wide-charset is the name of the character set that GDB
1203 uses when printing characters whose type is wchar_t.
1205 set tcp auto-retry (on|off)
1207 set tcp connect-timeout
1208 show tcp connect-timeout
1209 These commands allow GDB to retry failed TCP connections to a remote stub
1210 with a specified timeout period; this is useful if the stub is launched
1211 in parallel with GDB but may not be ready to accept connections immediately.
1213 set libthread-db-search-path
1214 show libthread-db-search-path
1215 Control list of directories which GDB will search for appropriate
1218 set schedule-multiple (on|off)
1219 show schedule-multiple
1220 Allow GDB to resume all threads of all processes or only threads of
1221 the current process.
1225 Use more aggressive caching for accesses to the stack. This improves
1226 performance of remote debugging (particularly backtraces) without
1227 affecting correctness.
1229 set interactive-mode (on|off|auto)
1230 show interactive-mode
1231 Control whether GDB runs in interactive mode (on) or not (off).
1232 When in interactive mode, GDB waits for the user to answer all
1233 queries. Otherwise, GDB does not wait and assumes the default
1234 answer. When set to auto (the default), GDB determines which
1235 mode to use based on the stdin settings.
1240 For program forks, this is replaced by the new more generic `info
1241 inferiors' command. To list checkpoints, you can still use the
1242 `info checkpoints' command, which was an alias for the `info forks'
1246 Replaced by the new `inferior' command. To switch between
1247 checkpoints, you can still use the `restart' command, which was an
1248 alias for the `fork' command.
1251 This is removed, since some targets don't have a notion of
1252 processes. To switch between processes, you can still use the
1253 `inferior' command using GDB's own inferior number.
1256 For program forks, this is replaced by the new more generic `kill
1257 inferior' command. To delete a checkpoint, you can still use the
1258 `delete checkpoint' command, which was an alias for the `delete
1262 For program forks, this is replaced by the new more generic `detach
1263 inferior' command. To detach a checkpoint, you can still use the
1264 `detach checkpoint' command, which was an alias for the `detach
1267 * New native configurations
1269 x86/x86_64 Darwin i[34567]86-*-darwin*
1271 x86_64 MinGW x86_64-*-mingw*
1275 Lattice Mico32 lm32-*
1276 x86 DICOS i[34567]86-*-dicos*
1277 x86_64 DICOS x86_64-*-dicos*
1280 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1281 (mingw32ce) debugging.
1287 These commands were actually not implemented on any target.
1289 *** Changes in GDB 6.8
1291 * New native configurations
1293 NetBSD/hppa hppa*-*netbsd*
1294 Xtensa GNU/Linux xtensa*-*-linux*
1298 NetBSD/hppa hppa*-*-netbsd*
1299 Xtensa GNU/Lunux xtensa*-*-linux*
1301 * Change in command line behavior -- corefiles vs. process ids.
1303 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1304 attaching to process NUMBER fails, GDB no longer attempts to open a
1305 core file named NUMBER. Attaching to a program using the -c option
1306 is no longer supported. Instead, use the '-p' or '--pid' options.
1308 * GDB can now be built as a native debugger for debugging Windows x86
1309 (mingw32) Portable Executable (PE) programs.
1311 * Pending breakpoints no longer change their number when their address
1314 * GDB now supports breakpoints with multiple locations,
1315 including breakpoints on C++ constructors, inside C++ templates,
1316 and in inlined functions.
1318 * GDB's ability to debug optimized code has been improved. GDB more
1319 accurately identifies function bodies and lexical blocks that occupy
1320 more than one contiguous range of addresses.
1322 * Target descriptions can now describe registers for PowerPC.
1324 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1325 registers on PowerPC targets.
1327 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1328 targets even when the libthread_db library is not available.
1330 * The GDB remote stub, gdbserver, now supports the new file transfer
1331 commands (remote put, remote get, and remote delete).
1333 * The GDB remote stub, gdbserver, now supports run and attach in
1334 extended-remote mode.
1336 * hppa*64*-*-hpux11* target broken
1337 The debugger is unable to start a program and fails with the following
1338 error: "Error trying to get information about dynamic linker".
1339 The gdb-6.7 release is also affected.
1341 * GDB now supports the --enable-targets= configure option to allow
1342 building a single GDB executable that supports multiple remote
1343 target architectures.
1345 * GDB now supports debugging C and C++ programs which use the
1346 Decimal Floating Point extension. In addition, the PowerPC target
1347 now has a set of pseudo-registers to inspect decimal float values
1348 stored in two consecutive float registers.
1350 * The -break-insert MI command can optionally create pending
1353 * Improved support for debugging Ada
1354 Many improvements to the Ada language support have been made. These
1356 - Better support for Ada2005 interface types
1357 - Improved handling of arrays and slices in general
1358 - Better support for Taft-amendment types
1359 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1361 - Improved command completion in Ada
1364 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1369 set print frame-arguments (all|scalars|none)
1370 show print frame-arguments
1371 The value of this variable can be changed to control which argument
1372 values should be printed by the debugger when displaying a frame.
1377 Transfer files to and from a remote target, and delete remote files.
1384 Transfer files to and from a remote target, and delete remote files.
1386 * New remote packets
1393 Open, close, read, write, and delete files on the remote system.
1396 Attach to an existing process on the remote system, in extended-remote
1400 Run a new process on the remote system, in extended-remote mode.
1402 *** Changes in GDB 6.7
1404 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1405 bfd, libiberty and opcodes, as revealed by static analysis donated by
1406 Coverity, Inc. (http://scan.coverity.com).
1408 * When looking up multiply-defined global symbols, GDB will now prefer the
1409 symbol definition in the current shared library if it was built using the
1410 -Bsymbolic linker option.
1412 * When the Text User Interface (TUI) is not configured, GDB will now
1413 recognize the -tui command-line option and print a message that the TUI
1416 * The GDB remote stub, gdbserver, now has lower overhead for high
1417 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1419 * GDB for MIPS targets now autodetects whether a remote target provides
1420 32-bit or 64-bit register values.
1422 * Support for C++ member pointers has been improved.
1424 * GDB now understands XML target descriptions, which specify the
1425 target's overall architecture. GDB can read a description from
1426 a local file or over the remote serial protocol.
1428 * Vectors of single-byte data use a new integer type which is not
1429 automatically displayed as character or string data.
1431 * The /s format now works with the print command. It displays
1432 arrays of single-byte integers and pointers to single-byte integers
1435 * Target descriptions can now describe target-specific registers,
1436 for architectures which have implemented the support (currently
1437 only ARM, M68K, and MIPS).
1439 * GDB and the GDB remote stub, gdbserver, now support the XScale
1442 * The GDB remote stub, gdbserver, has been updated to support
1443 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1444 has been rewritten to use the standard GDB remote protocol.
1446 * GDB can now step into C++ functions which are called through thunks.
1448 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1450 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1451 layout. It also supports a TextSeg= and DataSeg= response when only
1452 segment base addresses (rather than offsets) are available.
1454 * The /i format now outputs any trailing branch delay slot instructions
1455 immediately following the last instruction within the count specified.
1457 * The GDB remote protocol "T" stop reply packet now supports a
1458 "library" response. Combined with the new "qXfer:libraries:read"
1459 packet, this response allows GDB to debug shared libraries on targets
1460 where the operating system manages the list of loaded libraries (e.g.
1461 Windows and SymbianOS).
1463 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1464 (DLLs) on Windows and Windows CE targets.
1466 * GDB now supports a faster verification that a .debug file matches its binary
1467 according to its build-id signature, if the signature is present.
1473 Enable or disable hardware flow control (RTS/CTS) on the serial port
1474 when debugging using remote targets.
1476 set mem inaccessible-by-default
1477 show mem inaccessible-by-default
1478 If the target supplies a memory map, for instance via the remote
1479 protocol's "qXfer:memory-map:read" packet, setting this variable
1480 prevents GDB from accessing memory outside the memory map. This
1481 is useful for targets with memory mapped registers or which react
1482 badly to accesses of unmapped address space.
1484 set breakpoint auto-hw
1485 show breakpoint auto-hw
1486 If the target supplies a memory map, for instance via the remote
1487 protocol's "qXfer:memory-map:read" packet, setting this variable
1488 lets GDB use hardware breakpoints automatically for memory regions
1489 where it can not use software breakpoints. This covers both the
1490 "break" command and internal breakpoints used for other commands
1491 including "next" and "finish".
1494 catch exception unhandled
1495 Stop the program execution when Ada exceptions are raised.
1498 Stop the program execution when an Ada assertion failed.
1502 Set an alternate system root for target files. This is a more
1503 general version of "set solib-absolute-prefix", which is now
1504 an alias to "set sysroot".
1507 Provide extended SPU facility status information. This set of
1508 commands is available only when debugging the Cell/B.E. SPU
1511 * New native configurations
1513 OpenBSD/sh sh*-*openbsd*
1516 unset tdesc filename
1518 Use the specified local file as an XML target description, and do
1519 not query the target for its built-in description.
1523 OpenBSD/sh sh*-*-openbsd*
1524 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1525 Toshiba Media Processor mep-elf
1527 * New remote packets
1530 Ignore the specified signals; pass them directly to the debugged program
1531 without stopping other threads or reporting them to GDB.
1533 qXfer:features:read:
1534 Read an XML target description from the target, which describes its
1539 Read or write contents of an spufs file on the target system. These
1540 packets are available only on the Cell/B.E. SPU architecture.
1542 qXfer:libraries:read:
1543 Report the loaded shared libraries. Combined with new "T" packet
1544 response, this packet allows GDB to debug shared libraries on
1545 targets where the operating system manages the list of loaded
1546 libraries (e.g. Windows and SymbianOS).
1550 Support for these obsolete configurations has been removed.
1558 i[34567]86-*-lynxos*
1559 i[34567]86-*-netware*
1560 i[34567]86-*-sco3.2v5*
1561 i[34567]86-*-sco3.2v4*
1563 i[34567]86-*-sysv4.2*
1566 i[34567]86-*-unixware2*
1567 i[34567]86-*-unixware*
1576 * Other removed features
1583 Various m68k-only ROM monitors.
1590 Various Renesas ROM monitors and debugging interfaces for SH and
1595 Support for a Macraigor serial interface to on-chip debugging.
1596 GDB does not directly support the newer parallel or USB
1601 A debug information format. The predecessor to DWARF 2 and
1602 DWARF 3, which are still supported.
1604 Support for the HP aCC compiler on HP-UX/PA-RISC
1606 SOM-encapsulated symbolic debugging information, automatic
1607 invocation of pxdb, and the aCC custom C++ ABI. This does not
1608 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1609 with aCC can still be debugged on an assembly level.
1611 MIPS ".pdr" sections
1613 A MIPS-specific format used to describe stack frame layout
1614 in debugging information.
1618 GDB could work with an older version of Guile to debug
1619 the interpreter and Scheme programs running in it.
1621 set mips stack-arg-size
1622 set mips saved-gpreg-size
1624 Use "set mips abi" to control parameter passing for MIPS.
1626 *** Changes in GDB 6.6
1631 Cell Broadband Engine SPU spu-elf
1633 * GDB can now be configured as a cross-debugger targeting native Windows
1634 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1635 running on a Windows system over TCP/IP to debug Windows programs.
1637 * The GDB remote stub, gdbserver, has been updated to support Windows and
1638 Cygwin debugging. Both single-threaded and multi-threaded programs are
1641 * The "set trust-readonly-sections" command works again. This command was
1642 broken in GDB 6.3, 6.4, and 6.5.
1644 * The "load" command now supports writing to flash memory, if the remote
1645 stub provides the required support.
1647 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1648 longer requires symbolic debug information (e.g. DWARF-2).
1653 unset substitute-path
1654 show substitute-path
1655 Manage a list of substitution rules that GDB uses to rewrite the name
1656 of the directories where the sources are located. This can be useful
1657 for instance when the sources were moved to a different location
1658 between compilation and debugging.
1662 Print each CLI command as it is executed. Each command is prefixed with
1663 a number of `+' symbols representing the nesting depth.
1664 The source command now has a `-v' option to enable the same feature.
1668 The ARM Demon monitor support (RDP protocol, "target rdp").
1670 Kernel Object Display, an embedded debugging feature which only worked with
1671 an obsolete version of Cisco IOS.
1673 The 'set download-write-size' and 'show download-write-size' commands.
1675 * New remote packets
1678 Tell a stub about GDB client features, and request remote target features.
1679 The first feature implemented is PacketSize, which allows the target to
1680 specify the size of packets it can handle - to minimize the number of
1681 packets required and improve performance when connected to a remote
1685 Fetch an OS auxilliary vector from the remote stub. This packet is a
1686 more efficient replacement for qPart:auxv:read.
1688 qXfer:memory-map:read:
1689 Fetch a memory map from the remote stub, including information about
1690 RAM, ROM, and flash memory devices.
1695 Erase and program a flash memory device.
1697 * Removed remote packets
1700 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1701 used it, and only gdbserver implemented it.
1703 *** Changes in GDB 6.5
1707 Renesas M32C/M16C m32c-elf
1709 Morpho Technologies ms1 ms1-elf
1713 init-if-undefined Initialize a convenience variable, but
1714 only if it doesn't already have a value.
1716 The following commands are presently only implemented for native GNU/Linux:
1718 checkpoint Save a snapshot of the program state.
1720 restart <n> Return the program state to a
1721 previously saved state.
1723 info checkpoints List currently saved checkpoints.
1725 delete-checkpoint <n> Delete a previously saved checkpoint.
1727 set|show detach-on-fork Tell gdb whether to detach from a newly
1728 forked process, or to keep debugging it.
1730 info forks List forks of the user program that
1731 are available to be debugged.
1733 fork <n> Switch to debugging one of several
1734 forks of the user program that are
1735 available to be debugged.
1737 delete-fork <n> Delete a fork from the list of forks
1738 that are available to be debugged (and
1739 kill the forked process).
1741 detach-fork <n> Delete a fork from the list of forks
1742 that are available to be debugged (and
1743 allow the process to continue).
1747 Morpho Technologies ms2 ms1-elf
1749 * Improved Windows host support
1751 GDB now builds as a cross debugger hosted on i686-mingw32, including
1752 native console support, and remote communications using either
1753 network sockets or serial ports.
1755 * Improved Modula-2 language support
1757 GDB can now print most types in the Modula-2 syntax. This includes:
1758 basic types, set types, record types, enumerated types, range types,
1759 pointer types and ARRAY types. Procedure var parameters are correctly
1760 printed and hexadecimal addresses and character constants are also
1761 written in the Modula-2 syntax. Best results can be obtained by using
1762 GNU Modula-2 together with the -gdwarf-2 command line option.
1766 The ARM rdi-share module.
1768 The Netware NLM debug server.
1770 *** Changes in GDB 6.4
1772 * New native configurations
1774 OpenBSD/arm arm*-*-openbsd*
1775 OpenBSD/mips64 mips64-*-openbsd*
1779 Morpho Technologies ms1 ms1-elf
1781 * New command line options
1783 --batch-silent As for --batch, but totally silent.
1784 --return-child-result The debugger will exist with the same value
1785 the child (debugged) program exited with.
1786 --eval-command COMMAND, -ex COMMAND
1787 Execute a single GDB CLI command. This may be
1788 specified multiple times and in conjunction
1789 with the --command (-x) option.
1791 * Deprecated commands removed
1793 The following commands, that were deprecated in 2000, have been
1797 set|show arm disassembly-flavor set|show arm disassembler
1798 othernames set arm disassembler
1799 set|show remotedebug set|show debug remote
1800 set|show archdebug set|show debug arch
1801 set|show eventdebug set|show debug event
1804 * New BSD user-level threads support
1806 It is now possible to debug programs using the user-level threads
1807 library on OpenBSD and FreeBSD. Currently supported (target)
1810 FreeBSD/amd64 x86_64-*-freebsd*
1811 FreeBSD/i386 i386-*-freebsd*
1812 OpenBSD/i386 i386-*-openbsd*
1814 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1815 are not yet supported.
1817 * New support for Matsushita MN10300 w/sim added
1818 (Work in progress). mn10300-elf.
1820 * REMOVED configurations and files
1822 VxWorks and the XDR protocol *-*-vxworks
1823 Motorola MCORE mcore-*-*
1824 National Semiconductor NS32000 ns32k-*-*
1826 * New "set print array-indexes" command
1828 After turning this setting "on", GDB prints the index of each element
1829 when displaying arrays. The default is "off" to preserve the previous
1832 * VAX floating point support
1834 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1836 * User-defined command support
1838 In addition to using $arg0..$arg9 for argument passing, it is now possible
1839 to use $argc to determine now many arguments have been passed. See the
1840 section on user-defined commands in the user manual for more information.
1842 *** Changes in GDB 6.3:
1844 * New command line option
1846 GDB now accepts -l followed by a number to set the timeout for remote
1849 * GDB works with GCC -feliminate-dwarf2-dups
1851 GDB now supports a more compact representation of DWARF-2 debug
1852 information using DW_FORM_ref_addr references. These are produced
1853 by GCC with the option -feliminate-dwarf2-dups and also by some
1854 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1855 to use -feliminate-dwarf2-dups.
1857 * Internationalization
1859 When supported by the host system, GDB will be built with
1860 internationalization (libintl). The task of marking up the sources is
1861 continued, we're looking forward to our first translation.
1865 Initial support for debugging programs compiled with the GNAT
1866 implementation of the Ada programming language has been integrated
1867 into GDB. In this release, support is limited to expression evaluation.
1869 * New native configurations
1871 GNU/Linux/m32r m32r-*-linux-gnu
1875 GDB's remote protocol now includes support for the 'p' packet. This
1876 packet is used to fetch individual registers from a remote inferior.
1878 * END-OF-LIFE registers[] compatibility module
1880 GDB's internal register infrastructure has been completely rewritten.
1881 The new infrastructure making possible the implementation of key new
1882 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1885 GDB 6.3 will be the last release to include the the registers[]
1886 compatibility module that allowed out-of-date configurations to
1887 continue to work. This change directly impacts the following
1897 powerpc bdm protocol
1899 Unless there is activity to revive these configurations, they will be
1900 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1902 * OBSOLETE configurations and files
1904 Configurations that have been declared obsolete in this release have
1905 been commented out. Unless there is activity to revive these
1906 configurations, the next release of GDB will have their sources
1907 permanently REMOVED.
1916 *** Changes in GDB 6.2.1:
1918 * MIPS `break main; run' gave an heuristic-fence-post warning
1920 When attempting to run even a simple program, a warning about
1921 heuristic-fence-post being hit would be reported. This problem has
1924 * MIPS IRIX 'long double' crashed GDB
1926 When examining a long double variable, GDB would get a segmentation
1927 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1928 IRIX long double values).
1932 A bug in the VAX stack code was causing problems with the "next"
1933 command. This problem has been fixed.
1935 *** Changes in GDB 6.2:
1937 * Fix for ``many threads''
1939 On GNU/Linux systems that use the NPTL threads library, a program
1940 rapidly creating and deleting threads would confuse GDB leading to the
1943 ptrace: No such process.
1944 thread_db_get_info: cannot get thread info: generic error
1946 This problem has been fixed.
1948 * "-async" and "-noasync" options removed.
1950 Support for the broken "-noasync" option has been removed (it caused
1953 * New ``start'' command.
1955 This command runs the program until the begining of the main procedure.
1957 * New BSD Kernel Data Access Library (libkvm) interface
1959 Using ``target kvm'' it is now possible to debug kernel core dumps and
1960 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1961 platforms. Currently supported (native-only) configurations are:
1963 FreeBSD/amd64 x86_64-*-freebsd*
1964 FreeBSD/i386 i?86-*-freebsd*
1965 NetBSD/i386 i?86-*-netbsd*
1966 NetBSD/m68k m68*-*-netbsd*
1967 NetBSD/sparc sparc-*-netbsd*
1968 OpenBSD/amd64 x86_64-*-openbsd*
1969 OpenBSD/i386 i?86-*-openbsd*
1970 OpenBSD/m68k m68*-openbsd*
1971 OpenBSD/sparc sparc-*-openbsd*
1973 * Signal trampoline code overhauled
1975 Many generic problems with GDB's signal handling code have been fixed.
1976 These include: backtraces through non-contiguous stacks; recognition
1977 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1978 call; backtrace through a signal trampoline; step into and out of
1979 signal handlers; and single-stepping in the signal trampoline.
1981 Please note that kernel bugs are a limiting factor here. These
1982 features have been shown to work on an s390 GNU/Linux system that
1983 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1985 * Cygwin support for DWARF 2 added.
1987 * New native configurations
1989 GNU/Linux/hppa hppa*-*-linux*
1990 OpenBSD/hppa hppa*-*-openbsd*
1991 OpenBSD/m68k m68*-*-openbsd*
1992 OpenBSD/m88k m88*-*-openbsd*
1993 OpenBSD/powerpc powerpc-*-openbsd*
1994 NetBSD/vax vax-*-netbsd*
1995 OpenBSD/vax vax-*-openbsd*
1997 * END-OF-LIFE frame compatibility module
1999 GDB's internal frame infrastructure has been completely rewritten.
2000 The new infrastructure making it possible to support key new features
2001 including DWARF 2 Call Frame Information. To aid in the task of
2002 migrating old configurations to this new infrastructure, a
2003 compatibility module, that allowed old configurations to continue to
2004 work, was also included.
2006 GDB 6.2 will be the last release to include this frame compatibility
2007 module. This change directly impacts the following configurations:
2017 Unless there is activity to revive these configurations, they will be
2018 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2020 * REMOVED configurations and files
2022 Sun 3, running SunOS 3 m68*-*-sunos3*
2023 Sun 3, running SunOS 4 m68*-*-sunos4*
2024 Sun 2, running SunOS 3 m68000-*-sunos3*
2025 Sun 2, running SunOS 4 m68000-*-sunos4*
2026 Motorola 680x0 running LynxOS m68*-*-lynxos*
2027 AT&T 3b1/Unix pc m68*-att-*
2028 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2029 decstation mips-dec-* mips-little-*
2030 riscos mips-*-riscos* mips-*-sysv*
2031 sonymips mips-sony-*
2032 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2034 *** Changes in GDB 6.1.1:
2036 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2038 The TUI (Text-mode User Interface) is now built as part of a default
2039 GDB configuration. It is enabled by either selecting the TUI with the
2040 command line option "-i=tui" or by running the separate "gdbtui"
2041 program. For more information on the TUI, see the manual "Debugging
2044 * Pending breakpoint support (also included in GDB 6.1)
2046 Support has been added to allow you to specify breakpoints in shared
2047 libraries that have not yet been loaded. If a breakpoint location
2048 cannot be found, and the "breakpoint pending" option is set to auto,
2049 GDB queries you if you wish to make the breakpoint pending on a future
2050 shared-library load. If and when GDB resolves the breakpoint symbol,
2051 the pending breakpoint is removed as one or more regular breakpoints
2054 Pending breakpoints are very useful for GCJ Java debugging.
2056 * Fixed ISO-C build problems
2058 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2059 non ISO-C code that stopped them being built using a more strict ISO-C
2060 compiler (e.g., IBM's C compiler).
2062 * Fixed build problem on IRIX 5
2064 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2065 wasn't able to compile compile on an IRIX 5 system.
2067 * Added execute permission to gdb/gdbserver/configure
2069 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2070 permission. This bug would cause configure to fail on a number of
2071 systems (Solaris, IRIX). Ref: server/519.
2073 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2075 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2076 has been updated to use constant array sizes.
2078 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2080 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2081 its generated DWARF Call Frame Info. This encoding was causing GDB to
2082 panic, that panic has been fixed. Ref: gdb/1628.
2084 * Fixed a problem when examining parameters in shared library code.
2086 When examining parameters in optimized shared library code generated
2087 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2088 not available''. GDB now correctly displays the variable's value.
2090 *** Changes in GDB 6.1:
2092 * Removed --with-mmalloc
2094 Support for the mmalloc memory manager has been removed, as it
2095 conflicted with the internal gdb byte cache.
2097 * Changes in AMD64 configurations
2099 The AMD64 target now includes the %cs and %ss registers. As a result
2100 the AMD64 remote protocol has changed; this affects the floating-point
2101 and SSE registers. If you rely on those registers for your debugging,
2102 you should upgrade gdbserver on the remote side.
2104 * Revised SPARC target
2106 The SPARC target has been completely revised, incorporating the
2107 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2108 support for LynxOS and SunOS 4 has been dropped. Calling functions
2109 from within GDB on operating systems with a non-executable stack
2110 (Solaris, OpenBSD) now works.
2114 GDB has a new C++ demangler which does a better job on the mangled
2115 names generated by current versions of g++. It also runs faster, so
2116 with this and other changes gdb should now start faster on large C++
2119 * DWARF 2 Location Expressions
2121 GDB support for location expressions has been extended to support function
2122 arguments and frame bases. Older versions of GDB could crash when they
2125 * C++ nested types and namespaces
2127 GDB's support for nested types and namespaces in C++ has been
2128 improved, especially if you use the DWARF 2 debugging format. (This
2129 is the default for recent versions of GCC on most platforms.)
2130 Specifically, if you have a class "Inner" defined within a class or
2131 namespace "Outer", then GDB realizes that the class's name is
2132 "Outer::Inner", not simply "Inner". This should greatly reduce the
2133 frequency of complaints about not finding RTTI symbols. In addition,
2134 if you are stopped at inside of a function defined within a namespace,
2135 GDB modifies its name lookup accordingly.
2137 * New native configurations
2139 NetBSD/amd64 x86_64-*-netbsd*
2140 OpenBSD/amd64 x86_64-*-openbsd*
2141 OpenBSD/alpha alpha*-*-openbsd*
2142 OpenBSD/sparc sparc-*-openbsd*
2143 OpenBSD/sparc64 sparc64-*-openbsd*
2145 * New debugging protocols
2147 M32R with SDI protocol m32r-*-elf*
2149 * "set prompt-escape-char" command deleted.
2151 The command "set prompt-escape-char" has been deleted. This command,
2152 and its very obscure effet on GDB's prompt, was never documented,
2153 tested, nor mentioned in the NEWS file.
2155 * OBSOLETE configurations and files
2157 Configurations that have been declared obsolete in this release have
2158 been commented out. Unless there is activity to revive these
2159 configurations, the next release of GDB will have their sources
2160 permanently REMOVED.
2162 Sun 3, running SunOS 3 m68*-*-sunos3*
2163 Sun 3, running SunOS 4 m68*-*-sunos4*
2164 Sun 2, running SunOS 3 m68000-*-sunos3*
2165 Sun 2, running SunOS 4 m68000-*-sunos4*
2166 Motorola 680x0 running LynxOS m68*-*-lynxos*
2167 AT&T 3b1/Unix pc m68*-att-*
2168 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2169 decstation mips-dec-* mips-little-*
2170 riscos mips-*-riscos* mips-*-sysv*
2171 sonymips mips-sony-*
2172 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2174 * REMOVED configurations and files
2176 SGI Irix-4.x mips-sgi-irix4 or iris4
2177 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2178 Z8000 simulator z8k-zilog-none or z8ksim
2179 Matsushita MN10200 w/simulator mn10200-*-*
2180 H8/500 simulator h8500-hitachi-hms or h8500hms
2181 HP/PA running BSD hppa*-*-bsd*
2182 HP/PA running OSF/1 hppa*-*-osf*
2183 HP/PA Pro target hppa*-*-pro*
2184 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2185 386BSD i[3456]86-*-bsd*
2186 Sequent family i[3456]86-sequent-sysv4*
2187 i[3456]86-sequent-sysv*
2188 i[3456]86-sequent-bsd*
2189 SPARC running LynxOS sparc-*-lynxos*
2190 SPARC running SunOS 4 sparc-*-sunos4*
2191 Tsqware Sparclet sparclet-*-*
2192 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2194 *** Changes in GDB 6.0:
2198 Support for debugging the Objective-C programming language has been
2199 integrated into GDB.
2201 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2203 DWARF 2's Call Frame Information makes available compiler generated
2204 information that more exactly describes the program's run-time stack.
2205 By using this information, GDB is able to provide more robust stack
2208 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2209 have been updated to use a new backtrace mechanism which includes
2210 DWARF 2 CFI support.
2214 GDB's remote protocol has been extended to include support for hosted
2215 file I/O (where the remote target uses GDB's file system). See GDB's
2216 remote protocol documentation for details.
2218 * All targets using the new architecture framework.
2220 All of GDB's targets have been updated to use the new internal
2221 architecture framework. The way is now open for future GDB releases
2222 to include cross-architecture native debugging support (i386 on amd64,
2225 * GNU/Linux's Thread Local Storage (TLS)
2227 GDB now includes support for for the GNU/Linux implementation of
2228 per-thread variables.
2230 * GNU/Linux's Native POSIX Thread Library (NPTL)
2232 GDB's thread code has been updated to work with either the new
2233 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2235 * Separate debug info.
2237 GDB, in conjunction with BINUTILS, now supports a mechanism for
2238 automatically loading debug information from a separate file. Instead
2239 of shipping full debug and non-debug versions of system libraries,
2240 system integrators can now instead ship just the stripped libraries
2241 and optional debug files.
2243 * DWARF 2 Location Expressions
2245 DWARF 2 Location Expressions allow the compiler to more completely
2246 describe the location of variables (even in optimized code) to the
2249 GDB now includes preliminary support for location expressions (support
2250 for DW_OP_piece is still missing).
2254 A number of long standing bugs that caused GDB to die while starting a
2255 Java application have been fixed. GDB's Java support is now
2256 considered "useable".
2258 * GNU/Linux support for fork, vfork, and exec.
2260 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2261 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2264 * GDB supports logging output to a file
2266 There are two new commands, "set logging" and "show logging", which can be
2267 used to capture GDB's output to a file.
2269 * The meaning of "detach" has changed for gdbserver
2271 The "detach" command will now resume the application, as documented. To
2272 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2275 * d10v, m68hc11 `regs' command deprecated
2277 The `info registers' command has been updated so that it displays the
2278 registers using a format identical to the old `regs' command.
2282 A new command, "maint set profile on/off", has been added. This command can
2283 be used to enable or disable profiling while running GDB, to profile a
2284 session or a set of commands. In addition there is a new configure switch,
2285 "--enable-profiling", which will cause GDB to be compiled with profiling
2286 data, for more informative profiling results.
2288 * Default MI syntax changed to "mi2".
2290 The default MI (machine interface) syntax, enabled by the command line
2291 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2292 "mi1", can be enabled by specifying the option "-i=mi1".
2294 Support for the original "mi0" syntax (included in GDB 5.0) has been
2297 Fix for gdb/192: removed extraneous space when displaying frame level.
2298 Fix for gdb/672: update changelist is now output in mi list format.
2299 Fix for gdb/702: a -var-assign that updates the value now shows up
2300 in a subsequent -var-update.
2302 * New native configurations.
2304 FreeBSD/amd64 x86_64-*-freebsd*
2306 * Multi-arched targets.
2308 HP/PA HPUX11 hppa*-*-hpux*
2309 Renesas M32R/D w/simulator m32r-*-elf*
2311 * OBSOLETE configurations and files
2313 Configurations that have been declared obsolete in this release have
2314 been commented out. Unless there is activity to revive these
2315 configurations, the next release of GDB will have their sources
2316 permanently REMOVED.
2318 Z8000 simulator z8k-zilog-none or z8ksim
2319 Matsushita MN10200 w/simulator mn10200-*-*
2320 H8/500 simulator h8500-hitachi-hms or h8500hms
2321 HP/PA running BSD hppa*-*-bsd*
2322 HP/PA running OSF/1 hppa*-*-osf*
2323 HP/PA Pro target hppa*-*-pro*
2324 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2325 Sequent family i[3456]86-sequent-sysv4*
2326 i[3456]86-sequent-sysv*
2327 i[3456]86-sequent-bsd*
2328 Tsqware Sparclet sparclet-*-*
2329 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2331 * REMOVED configurations and files
2334 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2335 IBM AIX PS/2 i[3456]86-*-aix
2336 i386 running Mach 3.0 i[3456]86-*-mach3*
2337 i386 running Mach i[3456]86-*-mach*
2338 i386 running OSF/1 i[3456]86-*osf1mk*
2339 HP/Apollo 68k Family m68*-apollo*-sysv*,
2341 m68*-hp-bsd*, m68*-hp-hpux*
2342 Argonaut Risc Chip (ARC) arc-*-*
2343 Mitsubishi D30V d30v-*-*
2344 Fujitsu FR30 fr30-*-elf*
2345 OS/9000 i[34]86-*-os9k
2346 I960 with MON960 i960-*-coff
2348 * MIPS $fp behavior changed
2350 The convenience variable $fp, for the MIPS, now consistently returns
2351 the address of the current frame's base. Previously, depending on the
2352 context, $fp could refer to either $sp or the current frame's base
2353 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2354 The GNU Source-Level Debugger''.
2356 *** Changes in GDB 5.3:
2358 * GNU/Linux shared library multi-threaded performance improved.
2360 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2361 `/proc', in preference to `ptrace' for memory reads. This may result
2362 in an improvement in the start-up time of multi-threaded, shared
2363 library applications when run under GDB. One GDB user writes: ``loads
2364 shared libs like mad''.
2366 * ``gdbserver'' now supports multi-threaded applications on some targets
2368 Support for debugging multi-threaded applications which use
2369 the GNU/Linux LinuxThreads package has been added for
2370 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2371 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2373 * GDB now supports C/C++ preprocessor macros.
2375 GDB now expands preprocessor macro invocations in C/C++ expressions,
2376 and provides various commands for showing macro definitions and how
2379 The new command `macro expand EXPRESSION' expands any macro
2380 invocations in expression, and shows the result.
2382 The new command `show macro MACRO-NAME' shows the definition of the
2383 macro named MACRO-NAME, and where it was defined.
2385 Most compilers don't include information about macros in the debugging
2386 information by default. In GCC 3.1, for example, you need to compile
2387 your program with the options `-gdwarf-2 -g3'. If the macro
2388 information is present in the executable, GDB will read it.
2390 * Multi-arched targets.
2392 DEC Alpha (partial) alpha*-*-*
2393 DEC VAX (partial) vax-*-*
2395 National Semiconductor NS32000 (partial) ns32k-*-*
2396 Motorola 68000 (partial) m68k-*-*
2397 Motorola MCORE mcore-*-*
2401 Fujitsu FRV architecture added by Red Hat frv*-*-*
2404 * New native configurations
2406 Alpha NetBSD alpha*-*-netbsd*
2407 SH NetBSD sh*-*-netbsdelf*
2408 MIPS NetBSD mips*-*-netbsd*
2409 UltraSPARC NetBSD sparc64-*-netbsd*
2411 * OBSOLETE configurations and files
2413 Configurations that have been declared obsolete in this release have
2414 been commented out. Unless there is activity to revive these
2415 configurations, the next release of GDB will have their sources
2416 permanently REMOVED.
2418 Mitsubishi D30V d30v-*-*
2419 OS/9000 i[34]86-*-os9k
2420 IBM AIX PS/2 i[3456]86-*-aix
2421 Fujitsu FR30 fr30-*-elf*
2422 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2423 Argonaut Risc Chip (ARC) arc-*-*
2424 i386 running Mach 3.0 i[3456]86-*-mach3*
2425 i386 running Mach i[3456]86-*-mach*
2426 i386 running OSF/1 i[3456]86-*osf1mk*
2427 HP/Apollo 68k Family m68*-apollo*-sysv*,
2429 m68*-hp-bsd*, m68*-hp-hpux*
2430 I960 with MON960 i960-*-coff
2432 * OBSOLETE languages
2434 CHILL, a Pascal like language used by telecommunications companies.
2436 * REMOVED configurations and files
2438 AMD 29k family via UDI a29k-amd-udi, udi29k
2439 A29K VxWorks a29k-*-vxworks
2440 AMD 29000 embedded, using EBMON a29k-none-none
2441 AMD 29000 embedded with COFF a29k-none-coff
2442 AMD 29000 embedded with a.out a29k-none-aout
2444 testsuite/gdb.hp/gdb.threads-hp/ directory
2446 * New command "set max-user-call-depth <nnn>"
2448 This command allows the user to limit the call depth of user-defined
2449 commands. The default is 1024.
2451 * Changes in FreeBSD/i386 native debugging.
2453 Support for the "generate-core-file" has been added.
2455 * New commands "dump", "append", and "restore".
2457 These commands allow data to be copied from target memory
2458 to a bfd-format or binary file (dump and append), and back
2459 from a file into memory (restore).
2461 * Improved "next/step" support on multi-processor Alpha Tru64.
2463 The previous single-step mechanism could cause unpredictable problems,
2464 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2465 of a software single-step mechanism prevents this.
2467 *** Changes in GDB 5.2.1:
2475 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2476 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2477 Fix, by Joel Brobecker imported from mainline.
2479 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2480 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2481 Fix, by Fred Fish, imported from mainline.
2483 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2484 Surprisingly enough, it works now.
2485 By Michal Ludvig, imported from mainline.
2487 i386 hardware watchpoint support:
2488 avoid misses on second run for some targets.
2489 By Pierre Muller, imported from mainline.
2491 *** Changes in GDB 5.2:
2493 * New command "set trust-readonly-sections on[off]".
2495 This command is a hint that tells gdb that read-only sections
2496 really are read-only (ie. that their contents will not change).
2497 In this mode, gdb will go to the object file rather than the
2498 target to read memory from read-only sections (such as ".text").
2499 This can be a significant performance improvement on some
2500 (notably embedded) targets.
2502 * New command "generate-core-file" (or "gcore").
2504 This new gdb command allows the user to drop a core file of the child
2505 process state at any time. So far it's been implemented only for
2506 GNU/Linux and Solaris, but should be relatively easily ported to other
2507 hosts. Argument is core file name (defaults to core.<pid>).
2509 * New command line option
2511 GDB now accepts --pid or -p followed by a process id.
2513 * Change in command line behavior -- corefiles vs. process ids.
2515 There is a subtle behavior in the way in which GDB handles
2516 command line arguments. The first non-flag argument is always
2517 a program to debug, but the second non-flag argument may either
2518 be a corefile or a process id. Previously, GDB would attempt to
2519 open the second argument as a corefile, and if that failed, would
2520 issue a superfluous error message and then attempt to attach it as
2521 a process. Now, if the second argument begins with a non-digit,
2522 it will be treated as a corefile. If it begins with a digit,
2523 GDB will attempt to attach it as a process, and if no such process
2524 is found, will then attempt to open it as a corefile.
2526 * Changes in ARM configurations.
2528 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2529 configuration is fully multi-arch.
2531 * New native configurations
2533 ARM NetBSD arm*-*-netbsd*
2534 x86 OpenBSD i[3456]86-*-openbsd*
2535 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2536 Sparc64 running FreeBSD sparc64-*-freebsd*
2540 Sanyo XStormy16 xstormy16-elf
2542 * OBSOLETE configurations and files
2544 Configurations that have been declared obsolete in this release have
2545 been commented out. Unless there is activity to revive these
2546 configurations, the next release of GDB will have their sources
2547 permanently REMOVED.
2549 AMD 29k family via UDI a29k-amd-udi, udi29k
2550 A29K VxWorks a29k-*-vxworks
2551 AMD 29000 embedded, using EBMON a29k-none-none
2552 AMD 29000 embedded with COFF a29k-none-coff
2553 AMD 29000 embedded with a.out a29k-none-aout
2555 testsuite/gdb.hp/gdb.threads-hp/ directory
2557 * REMOVED configurations and files
2559 TI TMS320C80 tic80-*-*
2561 PowerPC Solaris powerpcle-*-solaris*
2562 PowerPC Windows NT powerpcle-*-cygwin32
2563 PowerPC Netware powerpc-*-netware*
2564 Harris/CXUX m88k m88*-harris-cxux*
2565 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2566 ns32k-utek-sysv* ns32k-utek-*
2567 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2568 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2569 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2570 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2571 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2573 * Changes to command line processing
2575 The new `--args' feature can be used to specify command-line arguments
2576 for the inferior from gdb's command line.
2578 * Changes to key bindings
2580 There is a new `operate-and-get-next' function bound to `C-o'.
2582 *** Changes in GDB 5.1.1
2584 Fix compile problem on DJGPP.
2586 Fix a problem with floating-point registers on the i386 being
2589 Fix to stop GDB crashing on .debug_str debug info.
2591 Numerous documentation fixes.
2593 Numerous testsuite fixes.
2595 *** Changes in GDB 5.1:
2597 * New native configurations
2599 Alpha FreeBSD alpha*-*-freebsd*
2600 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2601 MIPS GNU/Linux mips*-*-linux*
2602 MIPS SGI Irix 6.x mips*-sgi-irix6*
2603 ia64 AIX ia64-*-aix*
2604 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2608 Motorola 68HC11 and 68HC12 m68hc11-elf
2610 UltraSparc running GNU/Linux sparc64-*-linux*
2612 * OBSOLETE configurations and files
2614 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2615 Harris/CXUX m88k m88*-harris-cxux*
2616 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2617 ns32k-utek-sysv* ns32k-utek-*
2618 TI TMS320C80 tic80-*-*
2620 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2621 PowerPC Solaris powerpcle-*-solaris*
2622 PowerPC Windows NT powerpcle-*-cygwin32
2623 PowerPC Netware powerpc-*-netware*
2624 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2625 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2626 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2627 Apple Macintosh (MPW) host N/A
2629 stuff.c (Program to stuff files into a specially prepared space in kdb)
2630 kdb-start.c (Main loop for the standalone kernel debugger)
2632 Configurations that have been declared obsolete in this release have
2633 been commented out. Unless there is activity to revive these
2634 configurations, the next release of GDB will have their sources
2635 permanently REMOVED.
2637 * REMOVED configurations and files
2639 Altos 3068 m68*-altos-*
2640 Convex c1-*-*, c2-*-*
2642 ARM RISCix arm-*-* (as host)
2646 * GDB has been converted to ISO C.
2648 GDB's source code has been converted to ISO C. In particular, the
2649 sources are fully protoized, and rely on standard headers being
2654 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2656 * The MI enabled by default.
2658 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2659 revised and enabled by default. Packages which use GDB as a debugging
2660 engine behind a UI or another front end are encouraged to switch to
2661 using the GDB/MI interface, instead of the old annotations interface
2662 which is now deprecated.
2664 * Support for debugging Pascal programs.
2666 GDB now includes support for debugging Pascal programs. The following
2667 main features are supported:
2669 - Pascal-specific data types such as sets;
2671 - automatic recognition of Pascal sources based on file-name
2674 - Pascal-style display of data types, variables, and functions;
2676 - a Pascal expression parser.
2678 However, some important features are not yet supported.
2680 - Pascal string operations are not supported at all;
2682 - there are some problems with boolean types;
2684 - Pascal type hexadecimal constants are not supported
2685 because they conflict with the internal variables format;
2687 - support for Pascal objects and classes is not full yet;
2689 - unlike Pascal, GDB is case-sensitive for symbol names.
2691 * Changes in completion.
2693 Commands such as `shell', `run' and `set args', which pass arguments
2694 to inferior programs, now complete on file names, similar to what
2695 users expect at the shell prompt.
2697 Commands which accept locations, such as `disassemble', `print',
2698 `breakpoint', `until', etc. now complete on filenames as well as
2699 program symbols. Thus, if you type "break foob TAB", and the source
2700 files linked into the programs include `foobar.c', that file name will
2701 be one of the candidates for completion. However, file names are not
2702 considered for completion after you typed a colon that delimits a file
2703 name from a name of a function in that file, as in "break foo.c:bar".
2705 `set demangle-style' completes on available demangling styles.
2707 * New platform-independent commands:
2709 It is now possible to define a post-hook for a command as well as a
2710 hook that runs before the command. For more details, see the
2711 documentation of `hookpost' in the GDB manual.
2713 * Changes in GNU/Linux native debugging.
2715 Support for debugging multi-threaded programs has been completely
2716 revised for all platforms except m68k and sparc. You can now debug as
2717 many threads as your system allows you to have.
2719 Attach/detach is supported for multi-threaded programs.
2721 Support for SSE registers was added for x86. This doesn't work for
2722 multi-threaded programs though.
2724 * Changes in MIPS configurations.
2726 Multi-arch support is enabled for all MIPS configurations.
2728 GDB can now be built as native debugger on SGI Irix 6.x systems for
2729 debugging n32 executables. (Debugging 64-bit executables is not yet
2732 * Unified support for hardware watchpoints in all x86 configurations.
2734 Most (if not all) native x86 configurations support hardware-assisted
2735 breakpoints and watchpoints in a unified manner. This support
2736 implements debug register sharing between watchpoints, which allows to
2737 put a virtually infinite number of watchpoints on the same address,
2738 and also supports watching regions up to 16 bytes with several debug
2741 The new maintenance command `maintenance show-debug-regs' toggles
2742 debugging print-outs in functions that insert, remove, and test
2743 watchpoints and hardware breakpoints.
2745 * Changes in the DJGPP native configuration.
2747 New command ``info dos sysinfo'' displays assorted information about
2748 the CPU, OS, memory, and DPMI server.
2750 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2751 display information about segment descriptors stored in GDT, LDT, and
2754 New commands ``info dos pde'' and ``info dos pte'' display entries
2755 from Page Directory and Page Tables (for now works with CWSDPMI only).
2756 New command ``info dos address-pte'' displays the Page Table entry for
2757 a given linear address.
2759 GDB can now pass command lines longer than 126 characters to the
2760 program being debugged (requires an update to the libdbg.a library
2761 which is part of the DJGPP development kit).
2763 DWARF2 debug info is now supported.
2765 It is now possible to `step' and `next' through calls to `longjmp'.
2767 * Changes in documentation.
2769 All GDB documentation was converted to GFDL, the GNU Free
2770 Documentation License.
2772 Tracepoints-related commands are now fully documented in the GDB
2775 TUI, the Text-mode User Interface, is now documented in the manual.
2777 Tracepoints-related commands are now fully documented in the GDB
2780 The "GDB Internals" manual now has an index. It also includes
2781 documentation of `ui_out' functions, GDB coding standards, x86
2782 hardware watchpoints, and memory region attributes.
2784 * GDB's version number moved to ``version.in''
2786 The Makefile variable VERSION has been replaced by the file
2787 ``version.in''. People creating GDB distributions should update the
2788 contents of this file.
2792 GUD support is now a standard part of the EMACS distribution.
2794 *** Changes in GDB 5.0:
2796 * Improved support for debugging FP programs on x86 targets
2798 Unified and much-improved support for debugging floating-point
2799 programs on all x86 targets. In particular, ``info float'' now
2800 displays the FP registers in the same format on all x86 targets, with
2801 greater level of detail.
2803 * Improvements and bugfixes in hardware-assisted watchpoints
2805 It is now possible to watch array elements, struct members, and
2806 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2807 on x86 targets no longer erroneously trigger when the address is
2810 * Improvements in the native DJGPP version of GDB
2812 The distribution now includes all the scripts and auxiliary files
2813 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2814 machines ``out of the box''.
2816 The DJGPP version can now debug programs that use signals. It is
2817 possible to catch signals that happened in the debuggee, deliver
2818 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2819 would kill the program being debugged.) Programs that hook hardware
2820 interrupts (keyboard, timer, etc.) can also be debugged.
2822 It is now possible to debug DJGPP programs that redirect their
2823 standard handles or switch them to raw (as opposed to cooked) mode, or
2824 even close them. The command ``run < foo > bar'' works as expected,
2825 and ``info terminal'' reports useful information about the debuggee's
2826 terminal, including raw/cooked mode, redirection, etc.
2828 The DJGPP version now uses termios functions for console I/O, which
2829 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2832 DOS-style file names with drive letters are now fully supported by
2835 It is now possible to debug DJGPP programs that switch their working
2836 directory. It is also possible to rerun the debuggee any number of
2837 times without restarting GDB; thus, you can use the same setup,
2838 breakpoints, etc. for many debugging sessions.
2840 * New native configurations
2842 ARM GNU/Linux arm*-*-linux*
2843 PowerPC GNU/Linux powerpc-*-linux*
2847 Motorola MCore mcore-*-*
2848 x86 VxWorks i[3456]86-*-vxworks*
2849 PowerPC VxWorks powerpc-*-vxworks*
2850 TI TMS320C80 tic80-*-*
2852 * OBSOLETE configurations
2854 Altos 3068 m68*-altos-*
2855 Convex c1-*-*, c2-*-*
2857 ARM RISCix arm-*-* (as host)
2860 Configurations that have been declared obsolete will be commented out,
2861 but the code will be left in place. If there is no activity to revive
2862 these configurations before the next release of GDB, the sources will
2863 be permanently REMOVED.
2865 * Gould support removed
2867 Support for the Gould PowerNode and NP1 has been removed.
2869 * New features for SVR4
2871 On SVR4 native platforms (such as Solaris), if you attach to a process
2872 without first loading a symbol file, GDB will now attempt to locate and
2873 load symbols from the running process's executable file.
2875 * Many C++ enhancements
2877 C++ support has been greatly improved. Overload resolution now works properly
2878 in almost all cases. RTTI support is on the way.
2880 * Remote targets can connect to a sub-program
2882 A popen(3) style serial-device has been added. This device starts a
2883 sub-process (such as a stand-alone simulator) and then communicates
2884 with that. The sub-program to run is specified using the syntax
2885 ``|<program> <args>'' vis:
2887 (gdb) set remotedebug 1
2888 (gdb) target extended-remote |mn10300-elf-sim program-args
2890 * MIPS 64 remote protocol
2892 A long standing bug in the mips64 remote protocol where by GDB
2893 expected certain 32 bit registers (ex SR) to be transfered as 32
2894 instead of 64 bits has been fixed.
2896 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2897 added to provide backward compatibility with older versions of GDB.
2899 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2901 The command ``set remotebinarydownload'' command has been replaced by
2902 ``set remote X-packet''. Other commands in ``set remote'' family
2903 include ``set remote P-packet''.
2905 * Breakpoint commands accept ranges.
2907 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2908 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2909 ``tracepoint passcount'' also accepts a range of tracepoints.
2911 * ``apropos'' command added.
2913 The ``apropos'' command searches through command names and
2914 documentation strings, printing out matches, making it much easier to
2915 try to find a command that does what you are looking for.
2919 A new machine oriented interface (MI) has been added to GDB. This
2920 interface is designed for debug environments running GDB as a separate
2921 process. This is part of the long term libGDB project. See the
2922 "GDB/MI" chapter of the GDB manual for further information. It can be
2923 enabled by configuring with:
2925 .../configure --enable-gdbmi
2927 *** Changes in GDB-4.18:
2929 * New native configurations
2931 HP-UX 10.20 hppa*-*-hpux10.20
2932 HP-UX 11.x hppa*-*-hpux11.0*
2933 M68K GNU/Linux m68*-*-linux*
2937 Fujitsu FR30 fr30-*-elf*
2938 Intel StrongARM strongarm-*-*
2939 Mitsubishi D30V d30v-*-*
2941 * OBSOLETE configurations
2943 Gould PowerNode, NP1 np1-*-*, pn-*-*
2945 Configurations that have been declared obsolete will be commented out,
2946 but the code will be left in place. If there is no activity to revive
2947 these configurations before the next release of GDB, the sources will
2948 be permanently REMOVED.
2952 As a compatibility experiment, GDB's source files buildsym.h and
2953 buildsym.c have been converted to pure standard C, no longer
2954 containing any K&R compatibility code. We believe that all systems in
2955 use today either come with a standard C compiler, or have a GCC port
2956 available. If this is not true, please report the affected
2957 configuration to bug-gdb@gnu.org immediately. See the README file for
2958 information about getting a standard C compiler if you don't have one
2963 GDB now uses readline 2.2.
2965 * set extension-language
2967 You can now control the mapping between filename extensions and source
2968 languages by using the `set extension-language' command. For instance,
2969 you can ask GDB to treat .c files as C++ by saying
2970 set extension-language .c c++
2971 The command `info extensions' lists all of the recognized extensions
2972 and their associated languages.
2974 * Setting processor type for PowerPC and RS/6000
2976 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2977 you can use the `set processor' command to specify what variant of the
2978 PowerPC family you are debugging. The command
2982 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2983 following PowerPC and RS6000 variants:
2985 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2986 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2988 403GC IBM PowerPC 403GC
2989 505 Motorola PowerPC 505
2990 860 Motorola PowerPC 860 or 850
2991 601 Motorola PowerPC 601
2992 602 Motorola PowerPC 602
2993 603 Motorola/IBM PowerPC 603 or 603e
2994 604 Motorola PowerPC 604 or 604e
2995 750 Motorola/IBM PowerPC 750 or 750
2997 At the moment, this command just tells GDB what to name the
2998 special-purpose processor registers. Since almost all the affected
2999 registers are inaccessible to user-level programs, this command is
3000 only useful for remote debugging in its present form.
3004 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3005 more extensive support for HP-UX. Added features include shared
3006 library support, kernel threads and hardware watchpoints for 11.00,
3007 support for HP's ANSI C and C++ compilers, and a compatibility mode
3008 for xdb and dbx commands.
3012 HP's donation includes the new concept of catchpoints, which is a
3013 generalization of the old catch command. On HP-UX, it is now possible
3014 to catch exec, fork, and vfork, as well as library loading.
3016 This means that the existing catch command has changed; its first
3017 argument now specifies the type of catch to be set up. See the
3018 output of "help catch" for a list of catchpoint types.
3020 * Debugging across forks
3022 On HP-UX, you can choose which process to debug when a fork() happens
3027 HP has donated a curses-based terminal user interface (TUI). To get
3028 it, build with --enable-tui. Although this can be enabled for any
3029 configuration, at present it only works for native HP debugging.
3031 * GDB remote protocol additions
3033 A new protocol packet 'X' that writes binary data is now available.
3034 Default behavior is to try 'X', then drop back to 'M' if the stub
3035 fails to respond. The settable variable `remotebinarydownload'
3036 allows explicit control over the use of 'X'.
3038 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3039 full 64-bit address. The command
3041 set remoteaddresssize 32
3043 can be used to revert to the old behaviour. For existing remote stubs
3044 the change should not be noticed, as the additional address information
3047 In order to assist in debugging stubs, you may use the maintenance
3048 command `packet' to send any text string to the stub. For instance,
3050 maint packet heythere
3052 sends the packet "$heythere#<checksum>". Note that it is very easy to
3053 disrupt a debugging session by sending the wrong packet at the wrong
3056 The compare-sections command allows you to compare section data on the
3057 target to what is in the executable file without uploading or
3058 downloading, by comparing CRC checksums.
3060 * Tracing can collect general expressions
3062 You may now collect general expressions at tracepoints. This requires
3063 further additions to the target-side stub; see tracepoint.c and
3064 doc/agentexpr.texi for further details.
3066 * mask-address variable for Mips
3068 For Mips targets, you may control the zeroing of the upper 32 bits of
3069 a 64-bit address by entering `set mask-address on'. This is mainly
3070 of interest to users of embedded R4xxx and R5xxx processors.
3072 * Higher serial baud rates
3074 GDB's serial code now allows you to specify baud rates 57600, 115200,
3075 230400, and 460800 baud. (Note that your host system may not be able
3076 to achieve all of these rates.)
3080 The i960 configuration now includes an initial implementation of a
3081 builtin simulator, contributed by Jim Wilson.
3084 *** Changes in GDB-4.17:
3086 * New native configurations
3088 Alpha GNU/Linux alpha*-*-linux*
3089 Unixware 2.x i[3456]86-unixware2*
3090 Irix 6.x mips*-sgi-irix6*
3091 PowerPC GNU/Linux powerpc-*-linux*
3092 PowerPC Solaris powerpcle-*-solaris*
3093 Sparc GNU/Linux sparc-*-linux*
3094 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3098 Argonaut Risc Chip (ARC) arc-*-*
3099 Hitachi H8/300S h8300*-*-*
3100 Matsushita MN10200 w/simulator mn10200-*-*
3101 Matsushita MN10300 w/simulator mn10300-*-*
3102 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3103 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3104 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3105 Mitsubishi D10V w/simulator d10v-*-*
3106 Mitsubishi M32R/D w/simulator m32r-*-elf*
3107 Tsqware Sparclet sparclet-*-*
3108 NEC V850 w/simulator v850-*-*
3110 * New debugging protocols
3112 ARM with RDI protocol arm*-*-*
3113 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3114 DDB and LSI variants of PMON protocol mips*-*-*
3115 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3116 PowerPC with SDS protocol powerpc{,le}-*-eabi
3117 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3121 All configurations can now understand and use the DWARF 2 debugging
3122 format. The choice is automatic, if the symbol file contains DWARF 2
3127 GDB now includes basic Java language support. This support is
3128 only useful with Java compilers that produce native machine code.
3130 * solib-absolute-prefix and solib-search-path
3132 For SunOS and SVR4 shared libraries, you may now set the prefix for
3133 loading absolute shared library symbol files, and the search path for
3134 locating non-absolute shared library symbol files.
3136 * Live range splitting
3138 GDB can now effectively debug code for which GCC has performed live
3139 range splitting as part of its optimization. See gdb/doc/LRS for
3140 more details on the expected format of the stabs information.
3144 GDB's support for the GNU Hurd, including thread debugging, has been
3145 updated to work with current versions of the Hurd.
3149 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3150 instruction set. ARM GDB automatically detects when Thumb
3151 instructions are in use, and adjusts disassembly and backtracing
3156 GDB's MIPS target configurations now handle the MIP16 16-bit
3161 GDB now includes support for overlays; if an executable has been
3162 linked such that multiple sections are based at the same address, GDB
3163 will decide which section to use for symbolic info. You can choose to
3164 control the decision manually, using overlay commands, or implement
3165 additional target-side support and use "overlay load-target" to bring
3166 in the overlay mapping. Do "help overlay" for more detail.
3170 The command "info symbol <address>" displays information about
3171 the symbol at the specified address.
3175 The standard remote protocol now includes an extension that allows
3176 asynchronous collection and display of trace data. This requires
3177 extensive support in the target-side debugging stub. Tracing mode
3178 includes a new interaction mode in GDB and new commands: see the
3179 file tracepoint.c for more details.
3183 Configurations for embedded MIPS now include a simulator contributed
3184 by Cygnus Solutions. The simulator supports the instruction sets
3185 of most MIPS variants.
3189 Sparc configurations may now include the ERC32 simulator contributed
3190 by the European Space Agency. The simulator is not built into
3191 Sparc targets by default; configure with --enable-sim to include it.
3195 For target configurations that may include multiple variants of a
3196 basic architecture (such as MIPS and SH), you may now set the
3197 architecture explicitly. "set arch" sets, "info arch" lists
3198 the possible architectures.
3200 *** Changes in GDB-4.16:
3202 * New native configurations
3204 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3205 M68K NetBSD m68k-*-netbsd*
3206 PowerPC AIX 4.x powerpc-*-aix*
3207 PowerPC MacOS powerpc-*-macos*
3208 PowerPC Windows NT powerpcle-*-cygwin32
3209 RS/6000 AIX 4.x rs6000-*-aix4*
3213 ARM with RDP protocol arm-*-*
3214 I960 with MON960 i960-*-coff
3215 MIPS VxWorks mips*-*-vxworks*
3216 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3217 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3219 Matra Sparclet sparclet-*-*
3223 The powerpc-eabi configuration now includes the PSIM simulator,
3224 contributed by Andrew Cagney, with assistance from Mike Meissner.
3225 PSIM is a very elaborate model of the PowerPC, including not only
3226 basic instruction set execution, but also details of execution unit
3227 performance and I/O hardware. See sim/ppc/README for more details.
3231 GDB now works with Solaris 2.5.
3233 * Windows 95/NT native
3235 GDB will now work as a native debugger on Windows 95 and Windows NT.
3236 To build it from source, you must use the "gnu-win32" environment,
3237 which uses a DLL to emulate enough of Unix to run the GNU tools.
3238 Further information, binaries, and sources are available at
3239 ftp.cygnus.com, under pub/gnu-win32.
3241 * dont-repeat command
3243 If a user-defined command includes the command `dont-repeat', then the
3244 command will not be repeated if the user just types return. This is
3245 useful if the command is time-consuming to run, so that accidental
3246 extra keystrokes don't run the same command many times.
3248 * Send break instead of ^C
3250 The standard remote protocol now includes an option to send a break
3251 rather than a ^C to the target in order to interrupt it. By default,
3252 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3254 * Remote protocol timeout
3256 The standard remote protocol includes a new variable `remotetimeout'
3257 that allows you to set the number of seconds before GDB gives up trying
3258 to read from the target. The default value is 2.
3260 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3262 By default GDB will automatically keep track of objects as they are
3263 loaded and unloaded by the dynamic linker. By using the command `set
3264 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3265 when shared library events occur, thus allowing you to set breakpoints
3266 in shared libraries which are explicitly loaded by the inferior.
3268 Note this feature does not work on hpux8. On hpux9 you must link
3269 /usr/lib/end.o into your program. This feature should work
3270 automatically on hpux10.
3272 * Irix 5.x hardware watchpoint support
3274 Irix 5 configurations now support the use of hardware watchpoints.
3276 * Mips protocol "SYN garbage limit"
3278 When debugging a Mips target using the `target mips' protocol, you
3279 may set the number of characters that GDB will ignore by setting
3280 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3281 every character. The default value is 1050.
3283 * Recording and replaying remote debug sessions
3285 If you set `remotelogfile' to the name of a file, gdb will write to it
3286 a recording of a remote debug session. This recording may then be
3287 replayed back to gdb using "gdbreplay". See gdbserver/README for
3288 details. This is useful when you have a problem with GDB while doing
3289 remote debugging; you can make a recording of the session and send it
3290 to someone else, who can then recreate the problem.
3292 * Speedups for remote debugging
3294 GDB includes speedups for downloading and stepping MIPS systems using
3295 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3296 and more efficient S-record downloading.
3298 * Memory use reductions and statistics collection
3300 GDB now uses less memory and reports statistics about memory usage.
3301 Try the `maint print statistics' command, for example.
3303 *** Changes in GDB-4.15:
3305 * Psymtabs for XCOFF
3307 The symbol reader for AIX GDB now uses partial symbol tables. This
3308 can greatly improve startup time, especially for large executables.
3310 * Remote targets use caching
3312 Remote targets now use a data cache to speed up communication with the
3313 remote side. The data cache could lead to incorrect results because
3314 it doesn't know about volatile variables, thus making it impossible to
3315 debug targets which use memory mapped I/O devices. `set remotecache
3316 off' turns the the data cache off.
3318 * Remote targets may have threads
3320 The standard remote protocol now includes support for multiple threads
3321 in the target system, using new protocol commands 'H' and 'T'. See
3322 gdb/remote.c for details.
3326 If GDB is configured with `--enable-netrom', then it will include
3327 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3328 acts as though it is a bank of ROM on the target board, but you can
3329 write into it over the network. GDB's support consists only of
3330 support for fast loading into the emulated ROM; to debug, you must use
3331 another protocol, such as standard remote protocol. The usual
3332 sequence is something like
3334 target nrom <netrom-hostname>
3336 target remote <netrom-hostname>:1235
3340 GDB now includes support for the Apple Macintosh, as a host only. It
3341 may be run as either an MPW tool or as a standalone application, and
3342 it can debug through the serial port. All the usual GDB commands are
3343 available, but to the target command, you must supply "serial" as the
3344 device type instead of "/dev/ttyXX". See mpw-README in the main
3345 directory for more information on how to build. The MPW configuration
3346 scripts */mpw-config.in support only a few targets, and only the
3347 mips-idt-ecoff target has been tested.
3351 GDB configuration now uses autoconf. This is not user-visible,
3352 but does simplify configuration and building.
3356 GDB now supports hpux10.
3358 *** Changes in GDB-4.14:
3360 * New native configurations
3362 x86 FreeBSD i[345]86-*-freebsd
3363 x86 NetBSD i[345]86-*-netbsd
3364 NS32k NetBSD ns32k-*-netbsd
3365 Sparc NetBSD sparc-*-netbsd
3369 A29K VxWorks a29k-*-vxworks
3370 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3371 CPU32 EST-300 emulator m68*-*-est*
3372 PowerPC ELF powerpc-*-elf
3375 * Alpha OSF/1 support for procfs
3377 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3378 possible to attach to running processes. As the mounting of the /proc
3379 filesystem is optional on the Alpha, GDB automatically determines
3380 the availability of /proc during startup. This can lead to problems
3381 if /proc is unmounted after GDB has been started.
3383 * Arguments to user-defined commands
3385 User commands may accept up to 10 arguments separated by whitespace.
3386 Arguments are accessed within the user command via $arg0..$arg9. A
3389 print $arg0 + $arg1 + $arg2
3391 To execute the command use:
3394 Defines the command "adder" which prints the sum of its three arguments.
3395 Note the arguments are text substitutions, so they may reference variables,
3396 use complex expressions, or even perform inferior function calls.
3398 * New `if' and `while' commands
3400 This makes it possible to write more sophisticated user-defined
3401 commands. Both commands take a single argument, which is the
3402 expression to evaluate, and must be followed by the commands to
3403 execute, one per line, if the expression is nonzero, the list being
3404 terminated by the word `end'. The `if' command list may include an
3405 `else' word, which causes the following commands to be executed only
3406 if the expression is zero.
3408 * Fortran source language mode
3410 GDB now includes partial support for Fortran 77. It will recognize
3411 Fortran programs and can evaluate a subset of Fortran expressions, but
3412 variables and functions may not be handled correctly. GDB will work
3413 with G77, but does not yet know much about symbols emitted by other
3416 * Better HPUX support
3418 Most debugging facilities now work on dynamic executables for HPPAs
3419 running hpux9 or later. You can attach to running dynamically linked
3420 processes, but by default the dynamic libraries will be read-only, so
3421 for instance you won't be able to put breakpoints in them. To change
3422 that behavior do the following before running the program:
3428 This will cause the libraries to be mapped private and read-write.
3429 To revert to the normal behavior, do this:
3435 You cannot set breakpoints or examine data in the library until after
3436 the library is loaded if the function/data symbols do not have
3439 GDB can now also read debug symbols produced by the HP C compiler on
3440 HPPAs (sorry, no C++, Fortran or 68k support).
3442 * Target byte order now dynamically selectable
3444 You can choose which byte order to use with a target system, via the
3445 commands "set endian big" and "set endian little", and you can see the
3446 current setting by using "show endian". You can also give the command
3447 "set endian auto", in which case GDB will use the byte order
3448 associated with the executable. Currently, only embedded MIPS
3449 configurations support dynamic selection of target byte order.
3451 * New DOS host serial code
3453 This version uses DPMI interrupts to handle buffered I/O, so you
3454 no longer need to run asynctsr when debugging boards connected to
3457 *** Changes in GDB-4.13:
3459 * New "complete" command
3461 This lists all the possible completions for the rest of the line, if it
3462 were to be given as a command itself. This is intended for use by emacs.
3464 * Trailing space optional in prompt
3466 "set prompt" no longer adds a space for you after the prompt you set. This
3467 allows you to set a prompt which ends in a space or one that does not.
3469 * Breakpoint hit counts
3471 "info break" now displays a count of the number of times the breakpoint
3472 has been hit. This is especially useful in conjunction with "ignore"; you
3473 can ignore a large number of breakpoint hits, look at the breakpoint info
3474 to see how many times the breakpoint was hit, then run again, ignoring one
3475 less than that number, and this will get you quickly to the last hit of
3478 * Ability to stop printing at NULL character
3480 "set print null-stop" will cause GDB to stop printing the characters of
3481 an array when the first NULL is encountered. This is useful when large
3482 arrays actually contain only short strings.
3484 * Shared library breakpoints
3486 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3487 breakpoints in shared libraries before the executable is run.
3489 * Hardware watchpoints
3491 There is a new hardware breakpoint for the watch command for sparclite
3492 targets. See gdb/sparclite/hw_breakpoint.note.
3494 Hardware watchpoints are also now supported under GNU/Linux.
3498 Annotations have been added. These are for use with graphical interfaces,
3499 and are still experimental. Currently only gdba.el uses these.
3501 * Improved Irix 5 support
3503 GDB now works properly with Irix 5.2.
3505 * Improved HPPA support
3507 GDB now works properly with the latest GCC and GAS.
3509 * New native configurations
3511 Sequent PTX4 i[34]86-sequent-ptx4
3512 HPPA running OSF/1 hppa*-*-osf*
3513 Atari TT running SVR4 m68*-*-sysv4*
3514 RS/6000 LynxOS rs6000-*-lynxos*
3518 OS/9000 i[34]86-*-os9k
3519 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3522 * Hitachi SH7000 and E7000-PC ICE support
3524 There is now support for communicating with the Hitachi E7000-PC ICE.
3525 This is available automatically when GDB is configured for the SH.
3529 As usual, a variety of small fixes and improvements, both generic
3530 and configuration-specific. See the ChangeLog for more detail.
3532 *** Changes in GDB-4.12:
3534 * Irix 5 is now supported
3538 GDB-4.12 on the HPPA has a number of changes which make it unable
3539 to debug the output from the currently released versions of GCC and
3540 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3541 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3542 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3545 *** Changes in GDB-4.11:
3547 * User visible changes:
3551 The "set remotedebug" option is now consistent between the mips remote
3552 target, remote targets using the gdb-specific protocol, UDI (AMD's
3553 debug protocol for the 29k) and the 88k bug monitor. It is now an
3554 integer specifying a debug level (normally 0 or 1, but 2 means more
3555 debugging info for the mips target).
3557 * DEC Alpha native support
3559 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3560 debug info, but GDB works fairly well with the DEC compiler and should
3561 work with a future GCC release. See the README file for a few
3562 Alpha-specific notes.
3564 * Preliminary thread implementation
3566 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3568 * LynxOS native and target support for 386
3570 This release has been hosted on LynxOS 2.2, and also can be configured
3571 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3574 * Improvements in C++ mangling/demangling.
3576 This release has much better g++ debugging, specifically in name
3577 mangling/demangling, virtual function calls, print virtual table,
3578 call methods, ...etc.
3580 *** Changes in GDB-4.10:
3582 * User visible changes:
3584 Remote debugging using the GDB-specific (`target remote') protocol now
3585 supports the `load' command. This is only useful if you have some
3586 other way of getting the stub to the target system, and you can put it
3587 somewhere in memory where it won't get clobbered by the download.
3589 Filename completion now works.
3591 When run under emacs mode, the "info line" command now causes the
3592 arrow to point to the line specified. Also, "info line" prints
3593 addresses in symbolic form (as well as hex).
3595 All vxworks based targets now support a user settable option, called
3596 vxworks-timeout. This option represents the number of seconds gdb
3597 should wait for responses to rpc's. You might want to use this if
3598 your vxworks target is, perhaps, a slow software simulator or happens
3599 to be on the far side of a thin network line.
3603 This release contains support for using a DEC alpha as a GDB host for
3604 cross debugging. Native alpha debugging is not supported yet.
3607 *** Changes in GDB-4.9:
3611 This is the first GDB release which is accompanied by a matching testsuite.
3612 The testsuite requires installation of dejagnu, which should be available
3613 via ftp from most sites that carry GNU software.
3617 'Cfront' style demangling has had its name changed to 'ARM' style, to
3618 emphasize that it was written from the specifications in the C++ Annotated
3619 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3620 disclaimers, it still generated too much confusion with users attempting to
3621 use gdb with AT&T cfront.
3625 GDB now uses a standard remote interface to a simulator library.
3626 So far, the library contains simulators for the Zilog Z8001/2, the
3627 Hitachi H8/300, H8/500 and Super-H.
3629 * New targets supported
3631 H8/300 simulator h8300-hitachi-hms or h8300hms
3632 H8/500 simulator h8500-hitachi-hms or h8500hms
3633 SH simulator sh-hitachi-hms or sh
3634 Z8000 simulator z8k-zilog-none or z8ksim
3635 IDT MIPS board over serial line mips-idt-ecoff
3637 Cross-debugging to GO32 targets is supported. It requires a custom
3638 version of the i386-stub.c module which is integrated with the
3639 GO32 memory extender.
3641 * New remote protocols
3643 MIPS remote debugging protocol.
3645 * New source languages supported
3647 This version includes preliminary support for Chill, a Pascal like language
3648 used by telecommunications companies. Chill support is also being integrated
3649 into the GNU compiler, but we don't know when it will be publically available.
3652 *** Changes in GDB-4.8:
3654 * HP Precision Architecture supported
3656 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3657 version of this support was available as a set of patches from the
3658 University of Utah. GDB does not support debugging of programs
3659 compiled with the HP compiler, because HP will not document their file
3660 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3661 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3663 Many problems in the preliminary version have been fixed.
3665 * Faster and better demangling
3667 We have improved template demangling and fixed numerous bugs in the GNU style
3668 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3669 character types (wchar_t) are now supported. Demangling of each symbol is now
3670 only done once, and is cached when the symbol table for a file is read in.
3671 This results in a small increase in memory usage for C programs, a moderate
3672 increase in memory usage for C++ programs, and a fantastic speedup in
3675 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3676 from the specifications in the Annotated Reference Manual, which AT&T's
3677 compiler does not actually implement.
3679 * G++ multiple inheritance compiler problem
3681 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3682 inheritance lattices was reworked to properly discover ambiguities. We
3683 recently found an example which causes this new algorithm to fail in a
3684 very subtle way, producing bad debug information for those classes.
3685 The file 'gcc.patch' (in this directory) can be applied to gcc to
3686 circumvent the problem. A future GCC release will contain a complete
3689 The previous G++ debug info problem (mentioned below for the gdb-4.7
3690 release) is fixed in gcc version 2.3.2.
3692 * Improved configure script
3694 The `configure' script will now attempt to guess your system type if
3695 you don't supply a host system type. The old scheme of supplying a
3696 host system triplet is preferable over using this. All the magic is
3697 done in the new `config.guess' script. Examine it for details.
3699 We have also brought our configure script much more in line with the FSF's
3700 version. It now supports the --with-xxx options. In particular,
3701 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3702 The resulting GDB will not be able to read arbitrary object file formats --
3703 only the format ``expected'' to be used on the configured target system.
3704 We hope to make this the default in a future release.
3706 * Documentation improvements
3708 There's new internal documentation on how to modify GDB, and how to
3709 produce clean changes to the code. We implore people to read it
3710 before submitting changes.
3712 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3713 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3714 `info' files are also provided. To build `info' files from scratch,
3715 you will need the latest `makeinfo' release, which will be available in
3716 a future texinfo-X.Y release.
3718 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3719 We're not sure exactly which versions have this problem, but it has
3720 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3721 or better. If that isn't possible, there is a patch in
3722 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3723 around this problem.
3727 GDB now supports array constants that can be used in expressions typed in by
3728 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3729 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3732 The new directory `gdb/sparclite' contains a program that demonstrates
3733 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3735 * New native hosts supported
3737 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3738 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3740 * New targets supported
3742 AMD 29k family via UDI a29k-amd-udi or udi29k
3744 * New file formats supported
3746 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3747 HPUX core files, and SCO 3.2v2 core files.
3751 Attaching to processes now works again; thanks for the many bug reports.
3753 We have also stomped on a bunch of core dumps caused by
3754 printf_filtered("%s") problems.
3756 We eliminated a copyright problem on the rpc and ptrace header files
3757 for VxWorks, which was discovered at the last minute during the 4.7
3758 release. You should now be able to build a VxWorks GDB.
3760 You can now interrupt gdb while an attached process is running. This
3761 will cause the attached process to stop, and give control back to GDB.
3763 We fixed problems caused by using too many file descriptors
3764 for reading symbols from object files and libraries. This was
3765 especially a problem for programs that used many (~100) shared
3768 The `step' command now only enters a subroutine if there is line number
3769 information for the subroutine. Otherwise it acts like the `next'
3770 command. Previously, `step' would enter subroutines if there was
3771 any debugging information about the routine. This avoids problems
3772 when using `cc -g1' on MIPS machines.
3774 * Internal improvements
3776 GDB's internal interfaces have been improved to make it easier to support
3777 debugging of multiple languages in the future.
3779 GDB now uses a common structure for symbol information internally.
3780 Minimal symbols (derived from linkage symbols in object files), partial
3781 symbols (from a quick scan of debug information), and full symbols
3782 contain a common subset of information, making it easier to write
3783 shared code that handles any of them.
3785 * New command line options
3787 We now accept --silent as an alias for --quiet.
3791 The memory-mapped-malloc library is now licensed under the GNU Library
3792 General Public License.
3794 *** Changes in GDB-4.7:
3796 * Host/native/target split
3798 GDB has had some major internal surgery to untangle the support for
3799 hosts and remote targets. Now, when you configure GDB for a remote
3800 target, it will no longer load in all of the support for debugging
3801 local programs on the host. When fully completed and tested, this will
3802 ensure that arbitrary host/target combinations are possible.
3804 The primary conceptual shift is to separate the non-portable code in
3805 GDB into three categories. Host specific code is required any time GDB
3806 is compiled on that host, regardless of the target. Target specific
3807 code relates to the peculiarities of the target, but can be compiled on
3808 any host. Native specific code is everything else: it can only be
3809 built when the host and target are the same system. Child process
3810 handling and core file support are two common `native' examples.
3812 GDB's use of /proc for controlling Unix child processes is now cleaner.
3813 It has been split out into a single module under the `target_ops' vector,
3814 plus two native-dependent functions for each system that uses /proc.
3816 * New hosts supported
3818 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3819 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3820 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3822 * New targets supported
3824 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3825 68030 and CPU32 m68030-*-*, m68332-*-*
3827 * New native hosts supported
3829 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3830 (386bsd is not well tested yet)
3831 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3833 * New file formats supported
3835 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3836 supports reading of `a.out.adobe' object files, which are an a.out
3837 format extended with minimal information about multiple sections.
3841 `show copying' is the same as the old `info copying'.
3842 `show warranty' is the same as `info warrantee'.
3843 These were renamed for consistency. The old commands continue to work.
3845 `info handle' is a new alias for `info signals'.
3847 You can now define pre-command hooks, which attach arbitrary command
3848 scripts to any command. The commands in the hook will be executed
3849 prior to the user's command. You can also create a hook which will be
3850 executed whenever the program stops. See gdb.texinfo.
3854 We now deal with Cfront style name mangling, and can even extract type
3855 info from mangled symbols. GDB can automatically figure out which
3856 symbol mangling style your C++ compiler uses.
3858 Calling of methods and virtual functions has been improved as well.
3862 The crash that occured when debugging Sun Ansi-C compiled binaries is
3863 fixed. This was due to mishandling of the extra N_SO stabs output
3866 We also finally got Ultrix 4.2 running in house, and fixed core file
3867 support, with help from a dozen people on the net.
3869 John M. Farrell discovered that the reason that single-stepping was so
3870 slow on all of the Mips based platforms (primarily SGI and DEC) was
3871 that we were trying to demangle and lookup a symbol used for internal
3872 purposes on every instruction that was being stepped through. Changing
3873 the name of that symbol so that it couldn't be mistaken for a C++
3874 mangled symbol sped things up a great deal.
3876 Rich Pixley sped up symbol lookups in general by getting much smarter
3877 about when C++ symbol mangling is necessary. This should make symbol
3878 completion (TAB on the command line) much faster. It's not as fast as
3879 we'd like, but it's significantly faster than gdb-4.6.
3883 A new user controllable variable 'call_scratch_address' can
3884 specify the location of a scratch area to be used when GDB
3885 calls a function in the target. This is necessary because the
3886 usual method of putting the scratch area on the stack does not work
3887 in systems that have separate instruction and data spaces.
3889 We integrated changes to support the 29k UDI (Universal Debugger
3890 Interface), but discovered at the last minute that we didn't have all
3891 of the appropriate copyright paperwork. We are working with AMD to
3892 resolve this, and hope to have it available soon.
3896 We have sped up the remote serial line protocol, especially for targets
3897 with lots of registers. It now supports a new `expedited status' ('T')
3898 message which can be used in place of the existing 'S' status message.
3899 This allows the remote stub to send only the registers that GDB
3900 needs to make a quick decision about single-stepping or conditional
3901 breakpoints, eliminating the need to fetch the entire register set for
3902 each instruction being stepped through.
3904 The GDB remote serial protocol now implements a write-through cache for
3905 registers, only re-reading the registers if the target has run.
3907 There is also a new remote serial stub for SPARC processors. You can
3908 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3909 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3910 processor with a serial port.
3914 Configure.in files have become much easier to read and modify. A new
3915 `table driven' format makes it more obvious what configurations are
3916 supported, and what files each one uses.
3920 There is a new opcodes library which will eventually contain all of the
3921 disassembly routines and opcode tables. At present, it only contains
3922 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3923 disassembler (binutils/objdump) to share these routines.
3925 The libiberty library is now copylefted under the GNU Library General
3926 Public License. This allows more liberal use, and was done so libg++
3927 can use it. This makes no difference to GDB, since the Library License
3928 grants all the rights from the General Public License.
3932 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3933 reference to the stabs symbol info used by the debugger. It is (as far
3934 as we know) the only published document on this fascinating topic. We
3935 encourage you to read it, compare it to the stabs information on your
3936 system, and send improvements on the document in general (to
3937 bug-gdb@prep.ai.mit.edu).
3939 And, of course, many bugs have been fixed.
3942 *** Changes in GDB-4.6:
3944 * Better support for C++ function names
3946 GDB now accepts as input the "demangled form" of C++ overloaded function
3947 names and member function names, and can do command completion on such names
3948 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3949 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3950 Make use of command completion, it is your friend.
3952 GDB also now accepts a variety of C++ mangled symbol formats. They are
3953 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3954 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3955 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3956 for the list of formats.
3958 * G++ symbol mangling problem
3960 Recent versions of gcc have a bug in how they emit debugging information for
3961 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3962 directory) can be applied to gcc to fix the problem. Alternatively, if you
3963 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3964 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3965 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3968 * New 'maintenance' command
3970 All of the commands related to hacking GDB internals have been moved out of
3971 the main command set, and now live behind the 'maintenance' command. This
3972 can also be abbreviated as 'mt'. The following changes were made:
3974 dump-me -> maintenance dump-me
3975 info all-breakpoints -> maintenance info breakpoints
3976 printmsyms -> maintenance print msyms
3977 printobjfiles -> maintenance print objfiles
3978 printpsyms -> maintenance print psymbols
3979 printsyms -> maintenance print symbols
3981 The following commands are new:
3983 maintenance demangle Call internal GDB demangler routine to
3984 demangle a C++ link name and prints the result.
3985 maintenance print type Print a type chain for a given symbol
3987 * Change to .gdbinit file processing
3989 We now read the $HOME/.gdbinit file before processing the argv arguments
3990 (e.g. reading symbol files or core files). This allows global parameters to
3991 be set, which will apply during the symbol reading. The ./.gdbinit is still
3992 read after argv processing.
3994 * New hosts supported
3996 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3998 GNU/Linux support i386-unknown-linux or linux
4000 We are also including code to support the HP/PA running BSD and HPUX. This
4001 is almost guaranteed not to work, as we didn't have time to test or build it
4002 for this release. We are including it so that the more adventurous (or
4003 masochistic) of you can play with it. We also had major problems with the
4004 fact that the compiler that we got from HP doesn't support the -g option.
4007 * New targets supported
4009 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4011 * More smarts about finding #include files
4013 GDB now remembers the compilation directory for all include files, and for
4014 all files from which C is generated (like yacc and lex sources). This
4015 greatly improves GDB's ability to find yacc/lex sources, and include files,
4016 especially if you are debugging your program from a directory different from
4017 the one that contains your sources.
4019 We also fixed a bug which caused difficulty with listing and setting
4020 breakpoints in include files which contain C code. (In the past, you had to
4021 try twice in order to list an include file that you hadn't looked at before.)
4023 * Interesting infernals change
4025 GDB now deals with arbitrary numbers of sections, where the symbols for each
4026 section must be relocated relative to that section's landing place in the
4027 target's address space. This work was needed to support ELF with embedded
4028 stabs used by Solaris-2.0.
4030 * Bug fixes (of course!)
4032 There have been loads of fixes for the following things:
4033 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4034 i960, stabs, DOS(GO32), procfs, etc...
4036 See the ChangeLog for details.
4038 *** Changes in GDB-4.5:
4040 * New machines supported (host and target)
4042 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4044 SGI Irix-4.x mips-sgi-irix4 or iris4
4046 * New malloc package
4048 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4049 Mmalloc is capable of handling mutiple heaps of memory. It is also
4050 capable of saving a heap to a file, and then mapping it back in later.
4051 This can be used to greatly speedup the startup of GDB by using a
4052 pre-parsed symbol table which lives in a mmalloc managed heap. For
4053 more details, please read mmalloc/mmalloc.texi.
4057 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4058 'help info proc' for details.
4060 * MIPS ecoff symbol table format
4062 The code that reads MIPS symbol table format is now supported on all hosts.
4063 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4066 * File name changes for MS-DOS
4068 Many files in the config directories have been renamed to make it easier to
4069 support GDB on MS-DOSe systems (which have very restrictive file name
4070 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4071 environment) is close to working but has some remaining problems. Note
4072 that debugging of DOS programs is not supported, due to limitations
4073 in the ``operating system'', but it can be used to host cross-debugging.
4075 * Cross byte order fixes
4077 Many fixes have been made to support cross debugging of Sparc and MIPS
4078 targets from hosts whose byte order differs.
4080 * New -mapped and -readnow options
4082 If memory-mapped files are available on your system through the 'mmap'
4083 system call, you can use the -mapped option on the `file' or
4084 `symbol-file' commands to cause GDB to write the symbols from your
4085 program into a reusable file. If the program you are debugging is
4086 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4087 Future GDB debugging sessions will notice the presence of this file,
4088 and will quickly map in symbol information from it, rather than reading
4089 the symbol table from the executable program. Using the '-mapped'
4090 option in a GDB `file' or `symbol-file' command has the same effect as
4091 starting GDB with the '-mapped' command-line option.
4093 You can cause GDB to read the entire symbol table immediately by using
4094 the '-readnow' option with any of the commands that load symbol table
4095 information (or on the GDB command line). This makes the command
4096 slower, but makes future operations faster.
4098 The -mapped and -readnow options are typically combined in order to
4099 build a `fred.syms' file that contains complete symbol information.
4100 A simple GDB invocation to do nothing but build a `.syms' file for future
4103 gdb -batch -nx -mapped -readnow programname
4105 The `.syms' file is specific to the host machine on which GDB is run.
4106 It holds an exact image of GDB's internal symbol table. It cannot be
4107 shared across multiple host platforms.
4109 * longjmp() handling
4111 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4112 siglongjmp() without losing control. This feature has not yet been ported to
4113 all systems. It currently works on many 386 platforms, all MIPS-based
4114 platforms (SGI, DECstation, etc), and Sun3/4.
4118 Preliminary work has been put in to support the new Solaris OS from Sun. At
4119 this time, it can control and debug processes, but it is not capable of
4124 As always, many many bug fixes. The major areas were with g++, and mipsread.
4125 People using the MIPS-based platforms should experience fewer mysterious
4126 crashes and trashed symbol tables.
4128 *** Changes in GDB-4.4:
4130 * New machines supported (host and target)
4132 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4134 BSD Reno on Vax vax-dec-bsd
4135 Ultrix on Vax vax-dec-ultrix
4137 * New machines supported (target)
4139 AMD 29000 embedded, using EBMON a29k-none-none
4143 GDB continues to improve its handling of C++. `References' work better.
4144 The demangler has also been improved, and now deals with symbols mangled as
4145 per the Annotated C++ Reference Guide.
4147 GDB also now handles `stabs' symbol information embedded in MIPS
4148 `ecoff' symbol tables. Since the ecoff format was not easily
4149 extensible to handle new languages such as C++, this appeared to be a
4150 good way to put C++ debugging info into MIPS binaries. This option
4151 will be supported in the GNU C compiler, version 2, when it is
4154 * New features for SVR4
4156 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4157 shared libraries. Debugging dynamically linked programs should present
4158 only minor differences from debugging statically linked programs.
4160 The `info proc' command will print out information about any process
4161 on an SVR4 system (including the one you are debugging). At the moment,
4162 it prints the address mappings of the process.
4164 If you bring up GDB on another SVR4 system, please send mail to
4165 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4167 * Better dynamic linking support in SunOS
4169 Reading symbols from shared libraries which contain debugging symbols
4170 now works properly. However, there remain issues such as automatic
4171 skipping of `transfer vector' code during function calls, which
4172 make it harder to debug code in a shared library, than to debug the
4173 same code linked statically.
4177 GDB is now using the latest `getopt' routines from the FSF. This
4178 version accepts the -- prefix for options with long names. GDB will
4179 continue to accept the old forms (-option and +option) as well.
4180 Various single letter abbreviations for options have been explicity
4181 added to the option table so that they won't get overshadowed in the
4182 future by other options that begin with the same letter.
4186 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4187 Many assorted bugs have been handled. Many more remain to be handled.
4188 See the various ChangeLog files (primarily in gdb and bfd) for details.
4191 *** Changes in GDB-4.3:
4193 * New machines supported (host and target)
4195 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4196 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4197 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4199 * Almost SCO Unix support
4201 We had hoped to support:
4202 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4203 (except for core file support), but we discovered very late in the release
4204 that it has problems with process groups that render gdb unusable. Sorry
4205 about that. I encourage people to fix it and post the fixes.
4207 * Preliminary ELF and DWARF support
4209 GDB can read ELF object files on System V Release 4, and can handle
4210 debugging records for C, in DWARF format, in ELF files. This support
4211 is preliminary. If you bring up GDB on another SVR4 system, please
4212 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4217 GDB now uses the latest `readline' library. One user-visible change
4218 is that two tabs will list possible command completions, which previously
4219 required typing M-? (meta-question mark, or ESC ?).
4223 The `stepi' bug that many of you noticed has been squashed.
4224 Many bugs in C++ have been handled. Many more remain to be handled.
4225 See the various ChangeLog files (primarily in gdb and bfd) for details.
4227 * State of the MIPS world (in case you wondered):
4229 GDB can understand the symbol tables emitted by the compilers
4230 supplied by most vendors of MIPS-based machines, including DEC. These
4231 symbol tables are in a format that essentially nobody else uses.
4233 Some versions of gcc come with an assembler post-processor called
4234 mips-tfile. This program is required if you want to do source-level
4235 debugging of gcc-compiled programs. I believe FSF does not ship
4236 mips-tfile with gcc version 1, but it will eventually come with gcc
4239 Debugging of g++ output remains a problem. g++ version 1.xx does not
4240 really support it at all. (If you're lucky, you should be able to get
4241 line numbers and stack traces to work, but no parameters or local
4242 variables.) With some work it should be possible to improve the
4245 When gcc version 2 is released, you will have somewhat better luck.
4246 However, even then you will get confusing results for inheritance and
4249 We will eventually provide full debugging of g++ output on
4250 DECstations. This will probably involve some kind of stabs-in-ecoff
4251 encapulation, but the details have not been worked out yet.
4254 *** Changes in GDB-4.2:
4256 * Improved configuration
4258 Only one copy of `configure' exists now, and it is not self-modifying.
4259 Porting BFD is simpler.
4263 The `step' and `next' commands now only stop at the first instruction
4264 of a source line. This prevents the multiple stops that used to occur
4265 in switch statements, for-loops, etc. `Step' continues to stop if a
4266 function that has debugging information is called within the line.
4270 Lots of small bugs fixed. More remain.
4272 * New host supported (not target)
4274 Intel 386 PC clone running Mach i386-none-mach
4277 *** Changes in GDB-4.1:
4279 * Multiple source language support
4281 GDB now has internal scaffolding to handle several source languages.
4282 It determines the type of each source file from its filename extension,
4283 and will switch expression parsing and number formatting to match the
4284 language of the function in the currently selected stack frame.
4285 You can also specifically set the language to be used, with
4286 `set language c' or `set language modula-2'.
4290 GDB now has preliminary support for the GNU Modula-2 compiler,
4291 currently under development at the State University of New York at
4292 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4293 continue through the fall of 1991 and into 1992.
4295 Other Modula-2 compilers are currently not supported, and attempting to
4296 debug programs compiled with them will likely result in an error as the
4297 symbol table is read. Feel free to work on it, though!
4299 There are hooks in GDB for strict type checking and range checking,
4300 in the `Modula-2 philosophy', but they do not currently work.
4304 GDB can now write to executable and core files (e.g. patch
4305 a variable's value). You must turn this switch on, specify
4306 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4307 by assigning a new value to a variable. Modifications take
4310 * Automatic SunOS shared library reading
4312 When you run your program, GDB automatically determines where its
4313 shared libraries (if any) have been loaded, and reads their symbols.
4314 The `share' command is no longer needed. This also works when
4315 examining core files.
4319 You can specify the number of lines that the `list' command shows.
4322 * New machines supported (host and target)
4324 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4325 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4326 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4328 * New hosts supported (not targets)
4330 IBM RT/PC: romp-ibm-aix or rtpc
4332 * New targets supported (not hosts)
4334 AMD 29000 embedded with COFF a29k-none-coff
4335 AMD 29000 embedded with a.out a29k-none-aout
4336 Ultracomputer remote kernel debug a29k-nyu-kern
4338 * New remote interfaces
4344 *** Changes in GDB-4.0:
4348 Wide output is wrapped at good places to make the output more readable.
4350 Gdb now supports cross-debugging from a host machine of one type to a
4351 target machine of another type. Communication with the target system
4352 is over serial lines. The ``target'' command handles connecting to the
4353 remote system; the ``load'' command will download a program into the
4354 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4355 also supports debugging of realtime processes running under VxWorks,
4356 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4357 stub on the target system.
4359 New CPUs supported include the AMD 29000 and Intel 960.
4361 GDB now reads object files and symbol tables via a ``binary file''
4362 library, which allows a single copy of GDB to debug programs of multiple
4363 object file types such as a.out and coff.
4365 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4366 refcard.dvi and refcard.ps are available to format it).
4369 * Control-Variable user interface simplified
4371 All variables that control the operation of the debugger can be set
4372 by the ``set'' command, and displayed by the ``show'' command.
4374 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4375 ``Show prompt'' produces the response:
4376 Gdb's prompt is new-gdb=>.
4378 What follows are the NEW set commands. The command ``help set'' will
4379 print a complete list of old and new set commands. ``help set FOO''
4380 will give a longer description of the variable FOO. ``show'' will show
4381 all of the variable descriptions and their current settings.
4383 confirm on/off: Enables warning questions for operations that are
4384 hard to recover from, e.g. rerunning the program while
4385 it is already running. Default is ON.
4387 editing on/off: Enables EMACS style command line editing
4388 of input. Previous lines can be recalled with
4389 control-P, the current line can be edited with control-B,
4390 you can search for commands with control-R, etc.
4393 history filename NAME: NAME is where the gdb command history
4394 will be stored. The default is .gdb_history,
4395 or the value of the environment variable
4398 history size N: The size, in commands, of the command history. The
4399 default is 256, or the value of the environment variable
4402 history save on/off: If this value is set to ON, the history file will
4403 be saved after exiting gdb. If set to OFF, the
4404 file will not be saved. The default is OFF.
4406 history expansion on/off: If this value is set to ON, then csh-like
4407 history expansion will be performed on
4408 command line input. The default is OFF.
4410 radix N: Sets the default radix for input and output. It can be set
4411 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4412 in the current radix, so "set radix 10" is always a no-op.
4414 height N: This integer value is the number of lines on a page. Default
4415 is 24, the current `stty rows'' setting, or the ``li#''
4416 setting from the termcap entry matching the environment
4419 width N: This integer value is the number of characters on a line.
4420 Default is 80, the current `stty cols'' setting, or the ``co#''
4421 setting from the termcap entry matching the environment
4424 Note: ``set screensize'' is obsolete. Use ``set height'' and
4425 ``set width'' instead.
4427 print address on/off: Print memory addresses in various command displays,
4428 such as stack traces and structure values. Gdb looks
4429 more ``symbolic'' if you turn this off; it looks more
4430 ``machine level'' with it on. Default is ON.
4432 print array on/off: Prettyprint arrays. New convenient format! Default
4435 print demangle on/off: Print C++ symbols in "source" form if on,
4438 print asm-demangle on/off: Same, for assembler level printouts
4441 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4444 * Support for Epoch Environment.
4446 The epoch environment is a version of Emacs v18 with windowing. One
4447 new command, ``inspect'', is identical to ``print'', except that if you
4448 are running in the epoch environment, the value is printed in its own
4452 * Support for Shared Libraries
4454 GDB can now debug programs and core files that use SunOS shared libraries.
4455 Symbols from a shared library cannot be referenced
4456 before the shared library has been linked with the program (this
4457 happens after you type ``run'' and before the function main() is entered).
4458 At any time after this linking (including when examining core files
4459 from dynamically linked programs), gdb reads the symbols from each
4460 shared library when you type the ``sharedlibrary'' command.
4461 It can be abbreviated ``share''.
4463 sharedlibrary REGEXP: Load shared object library symbols for files
4464 matching a unix regular expression. No argument
4465 indicates to load symbols for all shared libraries.
4467 info sharedlibrary: Status of loaded shared libraries.
4472 A watchpoint stops execution of a program whenever the value of an
4473 expression changes. Checking for this slows down execution
4474 tremendously whenever you are in the scope of the expression, but is
4475 quite useful for catching tough ``bit-spreader'' or pointer misuse
4476 problems. Some machines such as the 386 have hardware for doing this
4477 more quickly, and future versions of gdb will use this hardware.
4479 watch EXP: Set a watchpoint (breakpoint) for an expression.
4481 info watchpoints: Information about your watchpoints.
4483 delete N: Deletes watchpoint number N (same as breakpoints).
4484 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4485 enable N: Re-enables watchpoint number N (same as breakpoints).
4488 * C++ multiple inheritance
4490 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4493 * C++ exception handling
4495 Gdb now supports limited C++ exception handling. Besides the existing
4496 ability to breakpoint on an exception handler, gdb can breakpoint on
4497 the raising of an exception (before the stack is peeled back to the
4500 catch FOO: If there is a FOO exception handler in the dynamic scope,
4501 set a breakpoint to catch exceptions which may be raised there.
4502 Multiple exceptions (``catch foo bar baz'') may be caught.
4504 info catch: Lists all exceptions which may be caught in the
4505 current stack frame.
4508 * Minor command changes
4510 The command ``call func (arg, arg, ...)'' now acts like the print
4511 command, except it does not print or save a value if the function's result
4512 is void. This is similar to dbx usage.
4514 The ``up'' and ``down'' commands now always print the frame they end up
4515 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4516 frames without printing.
4518 * New directory command
4520 'dir' now adds directories to the FRONT of the source search path.
4521 The path starts off empty. Source files that contain debug information
4522 about the directory in which they were compiled can be found even
4523 with an empty path; Sun CC and GCC include this information. If GDB can't
4524 find your source file in the current directory, type "dir .".
4526 * Configuring GDB for compilation
4528 For normal use, type ``./configure host''. See README or gdb.texinfo
4531 GDB now handles cross debugging. If you are remotely debugging between
4532 two different machines, type ``./configure host -target=targ''.
4533 Host is the machine where GDB will run; targ is the machine
4534 where the program that you are debugging will run.