1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.3
6 * The "maint set python print-stack on|off" command has been
7 deprecated, and a new command: "set python print-stack on|off" has
8 replaced it. Additionally, the default for "print-stack" is now
11 * libthread-db-search-path now supports two special values: $sdir and $pdir.
12 $sdir specifies the default system locations of shared libraries.
13 $pdir specifies the directory where the libpthread used by the application
16 GDB no longer looks in $sdir and $pdir after it has searched the directories
17 mentioned in libthread-db-search-path. If you want to search those
18 directories, they must be specified in libthread-db-search-path.
19 The default value of libthread-db-search-path on GNU/Linux and Solaris
20 systems is now "$sdir:$pdir".
22 $pdir is not supported by gdbserver, it is currently ignored.
23 $sdir is supported by gdbserver.
25 * New configure option --with-iconv-bin.
26 When using the internationalization support like the one in the GNU C
27 library, GDB will invoke the "iconv" program to get a list of supported
28 character sets. If this program lives in a non-standard location, one can
29 use this option to specify where to find it.
31 * When natively debugging programs on PowerPC BookE processors running
32 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
33 watchpoints, which specify a mask in addition to an address to watch.
34 The mask specifies that some bits of an address (the bits which are
35 reset in the mask) should be ignored when matching the address accessed
36 by the inferior against the watchpoint address. See the "PowerPC Embedded"
37 section in the user manual for more details.
39 * The new option --once causes GDBserver to stop listening for connections once
40 the first connection is made. The listening port used by GDBserver will
41 become available after that.
45 watch EXPRESSION mask MASK_VALUE
46 The watch command now supports the mask argument which allows creation
47 of masked watchpoints, if the current architecture supports this feature.
49 info auto-load-scripts [REGEXP]
50 This command was formerly named "maintenance print section-scripts".
51 It is now generally useful and is no longer a maintenance-only command.
53 * Tracepoints can now be enabled and disabled at any time after a trace
54 experiment has been started using the standard "enable" and "disable"
55 commands. It is now possible to start a trace experiment with no enabled
56 tracepoints; GDB will display a warning, but will allow the experiment to
57 begin, assuming that tracepoints will be enabled as needed while the trace
64 Dynamically enable a tracepoint in a started trace experiment.
68 Dynamically disable a tracepoint in a started trace experiment.
70 *** Changes in GDB 7.3
72 * GDB has a new command: "thread find [REGEXP]".
73 It finds the thread id whose name, target id, or thread extra info
74 matches the given regular expression.
76 * The "catch syscall" command now works on mips*-linux* targets.
78 * The -data-disassemble MI command now supports modes 2 and 3 for
79 dumping the instruction opcodes.
81 * New command line options
83 -data-directory DIR Specify DIR as the "data-directory".
84 This is mostly for testing purposes.
86 * The "maint set python auto-load on|off" command has been renamed to
87 "set auto-load-scripts on|off".
89 * GDB has a new command: "set directories".
90 It is like the "dir" command except that it replaces the
91 source path list instead of augmenting it.
93 * GDB now understands thread names.
95 On GNU/Linux, "info threads" will display the thread name as set by
96 prctl or pthread_setname_np.
98 There is also a new command, "thread name", which can be used to
99 assign a name internally for GDB to display.
102 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
103 has been integrated into GDB.
107 ** The function gdb.Write now accepts an optional keyword 'stream'.
108 This keyword, when provided, will direct the output to either
109 stdout, stderr, or GDB's logging output.
111 ** Parameters can now be be sub-classed in Python, and in particular
112 you may implement the get_set_doc and get_show_doc functions.
113 This improves how Parameter set/show documentation is processed
114 and allows for more dynamic content.
116 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
117 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
118 have an is_valid method.
120 ** Breakpoints can now be sub-classed in Python, and in particular
121 you may implement a 'stop' function that is executed each time
122 the inferior reaches that breakpoint.
124 ** New function gdb.lookup_global_symbol looks up a global symbol.
126 ** GDB values in Python are now callable if the value represents a
127 function. For example, if 'some_value' represents a function that
128 takes two integer parameters and returns a value, you can call
129 that function like so:
131 result = some_value (10,20)
133 ** Module gdb.types has been added.
134 It contains a collection of utilities for working with gdb.Types objects:
135 get_basic_type, has_field, make_enum_dict.
137 ** Module gdb.printing has been added.
138 It contains utilities for writing and registering pretty-printers.
139 New classes: PrettyPrinter, SubPrettyPrinter,
140 RegexpCollectionPrettyPrinter.
141 New function: register_pretty_printer.
143 ** New commands "info pretty-printers", "enable pretty-printer" and
144 "disable pretty-printer" have been added.
146 ** gdb.parameter("directories") is now available.
148 ** New function gdb.newest_frame returns the newest frame in the
151 ** The gdb.InferiorThread class has a new "name" attribute. This
152 holds the thread's name.
154 ** Python Support for Inferior events.
155 Python scripts can add observers to be notified of events
156 occurring in the process being debugged.
157 The following events are currently supported:
158 - gdb.events.cont Continue event.
159 - gdb.events.exited Inferior exited event.
160 - gdb.events.stop Signal received, and Breakpoint hit events.
164 ** GDB now puts template parameters in scope when debugging in an
165 instantiation. For example, if you have:
167 template<int X> int func (void) { return X; }
169 then if you step into func<5>, "print X" will show "5". This
170 feature requires proper debuginfo support from the compiler; it
171 was added to GCC 4.5.
173 ** The motion commands "next", "finish", "until", and "advance" now
174 work better when exceptions are thrown. In particular, GDB will
175 no longer lose control of the inferior; instead, the GDB will
176 stop the inferior at the point at which the exception is caught.
177 This functionality requires a change in the exception handling
178 code that was introduced in GCC 4.5.
180 * GDB now follows GCC's rules on accessing volatile objects when
181 reading or writing target state during expression evaluation.
182 One notable difference to prior behavior is that "print x = 0"
183 no longer generates a read of x; the value of the assignment is
184 now always taken directly from the value being assigned.
186 * GDB now has some support for using labels in the program's source in
187 linespecs. For instance, you can use "advance label" to continue
188 execution to a label.
190 * GDB now has support for reading and writing a new .gdb_index
191 section. This section holds a fast index of DWARF debugging
192 information and can be used to greatly speed up GDB startup and
193 operation. See the documentation for `save gdb-index' for details.
195 * The "watch" command now accepts an optional "-location" argument.
196 When used, this causes GDB to watch the memory referred to by the
197 expression. Such a watchpoint is never deleted due to it going out
200 * GDB now supports thread debugging of core dumps on GNU/Linux.
202 GDB now activates thread debugging using the libthread_db library
203 when debugging GNU/Linux core dumps, similarly to when debugging
204 live processes. As a result, when debugging a core dump file, GDB
205 is now able to display pthread_t ids of threads. For example, "info
206 threads" shows the same output as when debugging the process when it
207 was live. In earlier releases, you'd see something like this:
210 * 1 LWP 6780 main () at main.c:10
212 While now you see this:
215 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
217 It is also now possible to inspect TLS variables when debugging core
220 When debugging a core dump generated on a machine other than the one
221 used to run GDB, you may need to point GDB at the correct
222 libthread_db library with the "set libthread-db-search-path"
223 command. See the user manual for more details on this command.
225 * When natively debugging programs on PowerPC BookE processors running
226 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
227 which stop execution of the inferior whenever it executes an instruction
228 at any address within the specified range. See the "PowerPC Embedded"
229 section in the user manual for more details.
231 * New features in the GDB remote stub, GDBserver
233 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
234 and i686 LynxOS (version 5.x).
236 ** GDBserver is now supported on Blackfin Linux.
238 * New native configurations
240 ia64 HP-UX ia64-*-hpux*
244 Analog Devices, Inc. Blackfin Processor bfin-*
246 * Ada task switching is now supported on sparc-elf targets when
247 debugging a program using the Ravenscar Profile. For more information,
248 see the "Tasking Support when using the Ravenscar Profile" section
249 in the GDB user manual.
251 * Guile support was removed.
253 * New features in the GNU simulator
255 ** The --map-info flag lists all known core mappings.
257 ** CFI flashes may be simulated via the "cfi" device.
259 *** Changes in GDB 7.2
261 * Shared library support for remote targets by default
263 When GDB is configured for a generic, non-OS specific target, like
264 for example, --target=arm-eabi or one of the many *-*-elf targets,
265 GDB now queries remote stubs for loaded shared libraries using the
266 `qXfer:libraries:read' packet. Previously, shared library support
267 was always disabled for such configurations.
271 ** Argument Dependent Lookup (ADL)
273 In C++ ADL lookup directs function search to the namespaces of its
274 arguments even if the namespace has not been imported.
284 Here the compiler will search for `foo' in the namespace of 'b'
285 and find A::foo. GDB now supports this. This construct is commonly
286 used in the Standard Template Library for operators.
288 ** Improved User Defined Operator Support
290 In addition to member operators, GDB now supports lookup of operators
291 defined in a namespace and imported with a `using' directive, operators
292 defined in the global scope, operators imported implicitly from an
293 anonymous namespace, and the ADL operators mentioned in the previous
295 GDB now also supports proper overload resolution for all the previously
296 mentioned flavors of operators.
298 ** static const class members
300 Printing of static const class members that are initialized in the
301 class definition has been fixed.
303 * Windows Thread Information Block access.
305 On Windows targets, GDB now supports displaying the Windows Thread
306 Information Block (TIB) structure. This structure is visible either
307 by using the new command `info w32 thread-information-block' or, by
308 dereferencing the new convenience variable named `$_tlb', a
309 thread-specific pointer to the TIB. This feature is also supported
310 when remote debugging using GDBserver.
314 Static tracepoints are calls in the user program into a tracing
315 library. One such library is a port of the LTTng kernel tracer to
316 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
317 When debugging with GDBserver, GDB now supports combining the GDB
318 tracepoint machinery with such libraries. For example: the user can
319 use GDB to probe a static tracepoint marker (a call from the user
320 program into the tracing library) with the new "strace" command (see
321 "New commands" below). This creates a "static tracepoint" in the
322 breakpoint list, that can be manipulated with the same feature set
323 as fast and regular tracepoints. E.g., collect registers, local and
324 global variables, collect trace state variables, and define
325 tracepoint conditions. In addition, the user can collect extra
326 static tracepoint marker specific data, by collecting the new
327 $_sdata internal variable. When analyzing the trace buffer, you can
328 inspect $_sdata like any other variable available to GDB. For more
329 information, see the "Tracepoints" chapter in GDB user manual. New
330 remote packets have been defined to support static tracepoints, see
331 the "New remote packets" section below.
333 * Better reconstruction of tracepoints after disconnected tracing
335 GDB will attempt to download the original source form of tracepoint
336 definitions when starting a trace run, and then will upload these
337 upon reconnection to the target, resulting in a more accurate
338 reconstruction of the tracepoints that are in use on the target.
342 You can now exercise direct control over the ways that GDB can
343 affect your program. For instance, you can disallow the setting of
344 breakpoints, so that the program can run continuously (assuming
345 non-stop mode). In addition, the "observer" variable is available
346 to switch all of the different controls; in observer mode, GDB
347 cannot affect the target's behavior at all, which is useful for
348 tasks like diagnosing live systems in the field.
350 * The new convenience variable $_thread holds the number of the
357 Return the address of the Windows Thread Information Block of a given thread.
361 In response to several of the tracepoint packets, the target may now
362 also respond with a number of intermediate `qRelocInsn' request
363 packets before the final result packet, to have GDB handle
364 relocating an instruction to execute at a different address. This
365 is particularly useful for stubs that support fast tracepoints. GDB
366 reports support for this feature in the qSupported packet.
370 List static tracepoint markers in the target program.
374 List static tracepoint markers at a given address in the target
377 qXfer:statictrace:read
379 Read the static trace data collected (by a `collect $_sdata'
380 tracepoint action). The remote stub reports support for this packet
381 to gdb's qSupported query.
385 Send the current settings of GDB's permission flags.
389 Send part of the source (textual) form of a tracepoint definition,
390 which includes location, conditional, and action list.
392 * The source command now accepts a -s option to force searching for the
393 script in the source search path even if the script name specifies
396 * New features in the GDB remote stub, GDBserver
398 - GDBserver now support tracepoints (including fast tracepoints, and
399 static tracepoints). The feature is currently supported by the
400 i386-linux and amd64-linux builds. See the "Tracepoints support
401 in gdbserver" section in the manual for more information.
403 GDBserver JIT compiles the tracepoint's conditional agent
404 expression bytecode into native code whenever possible for low
405 overhead dynamic tracepoints conditionals. For such tracepoints,
406 an expression that examines program state is evaluated when the
407 tracepoint is reached, in order to determine whether to capture
408 trace data. If the condition is simple and false, processing the
409 tracepoint finishes very quickly and no data is gathered.
411 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
412 for static tracepoints support.
414 - GDBserver now supports x86_64 Windows 64-bit debugging.
416 * GDB now sends xmlRegisters= in qSupported packet to indicate that
417 it understands register description.
419 * The --batch flag now disables pagination and queries.
421 * X86 general purpose registers
423 GDB now supports reading/writing byte, word and double-word x86
424 general purpose registers directly. This means you can use, say,
425 $ah or $ax to refer, respectively, to the byte register AH and
426 16-bit word register AX that are actually portions of the 32-bit
427 register EAX or 64-bit register RAX.
429 * The `commands' command now accepts a range of breakpoints to modify.
430 A plain `commands' following a command that creates multiple
431 breakpoints affects all the breakpoints set by that command. This
432 applies to breakpoints set by `rbreak', and also applies when a
433 single `break' command creates multiple breakpoints (e.g.,
434 breakpoints on overloaded c++ functions).
436 * The `rbreak' command now accepts a filename specification as part of
437 its argument, limiting the functions selected by the regex to those
438 in the specified file.
440 * Support for remote debugging Windows and SymbianOS shared libraries
441 from Unix hosts has been improved. Non Windows GDB builds now can
442 understand target reported file names that follow MS-DOS based file
443 system semantics, such as file names that include drive letters and
444 use the backslash character as directory separator. This makes it
445 possible to transparently use the "set sysroot" and "set
446 solib-search-path" on Unix hosts to point as host copies of the
447 target's shared libraries. See the new command "set
448 target-file-system-kind" described below, and the "Commands to
449 specify files" section in the user manual for more information.
453 eval template, expressions...
454 Convert the values of one or more expressions under the control
455 of the string template to a command line, and call it.
457 set target-file-system-kind unix|dos-based|auto
458 show target-file-system-kind
459 Set or show the assumed file system kind for target reported file
462 save breakpoints <filename>
463 Save all current breakpoint definitions to a file suitable for use
464 in a later debugging session. To read the saved breakpoint
465 definitions, use the `source' command.
467 `save tracepoints' is a new alias for `save-tracepoints'. The latter
470 info static-tracepoint-markers
471 Display information about static tracepoint markers in the target.
473 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
474 Define a static tracepoint by probing a marker at the given
475 function, line, address, or marker ID.
479 Enable and disable observer mode.
481 set may-write-registers on|off
482 set may-write-memory on|off
483 set may-insert-breakpoints on|off
484 set may-insert-tracepoints on|off
485 set may-insert-fast-tracepoints on|off
486 set may-interrupt on|off
487 Set individual permissions for GDB effects on the target. Note that
488 some of these settings can have undesirable or surprising
489 consequences, particularly when changed in the middle of a session.
490 For instance, disabling the writing of memory can prevent
491 breakpoints from being inserted, cause single-stepping to fail, or
492 even crash your program, if you disable after breakpoints have been
493 inserted. However, GDB should not crash.
495 set record memory-query on|off
496 show record memory-query
497 Control whether to stop the inferior if memory changes caused
498 by an instruction cannot be recorded.
503 The disassemble command now supports "start,+length" form of two arguments.
507 ** GDB now provides a new directory location, called the python directory,
508 where Python scripts written for GDB can be installed. The location
509 of that directory is <data-directory>/python, where <data-directory>
510 is the GDB data directory. For more details, see section `Scripting
511 GDB using Python' in the manual.
513 ** The GDB Python API now has access to breakpoints, symbols, symbol
514 tables, program spaces, inferiors, threads and frame's code blocks.
515 Additionally, GDB Parameters can now be created from the API, and
516 manipulated via set/show in the CLI.
518 ** New functions gdb.target_charset, gdb.target_wide_charset,
519 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
521 ** New exception gdb.GdbError.
523 ** Pretty-printers are now also looked up in the current program space.
525 ** Pretty-printers can now be individually enabled and disabled.
527 ** GDB now looks for names of Python scripts to auto-load in a
528 special section named `.debug_gdb_scripts', in addition to looking
529 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
531 * Tracepoint actions were unified with breakpoint commands. In particular,
532 there are no longer differences in "info break" output for breakpoints and
533 tracepoints and the "commands" command can be used for both tracepoints and
538 ARM Symbian arm*-*-symbianelf*
540 * D language support.
541 GDB now supports debugging programs written in the D programming
544 * GDB now supports the extended ptrace interface for PowerPC which is
545 available since Linux kernel version 2.6.34. This automatically enables
546 any hardware breakpoints and additional hardware watchpoints available in
547 the processor. The old ptrace interface exposes just one hardware
548 watchpoint and no hardware breakpoints.
550 * GDB is now able to use the Data Value Compare (DVC) register available on
551 embedded PowerPC processors to implement in hardware simple watchpoint
552 conditions of the form:
554 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
556 This works in native GDB running on Linux kernels with the extended ptrace
557 interface mentioned above.
559 *** Changes in GDB 7.1
565 GDB now supports importing of namespaces in C++. This enables the
566 user to inspect variables from imported namespaces. Support for
567 namepace aliasing has also been added. So, if a namespace is
568 aliased in the current scope (e.g. namepace C=A; ) the user can
569 print variables using the alias (e.g. (gdb) print C::x).
573 All known bugs relating to the printing of virtual base class were
574 fixed. It is now possible to call overloaded static methods using a
579 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
580 and reinterpret_cast<> are now handled by the C++ expression parser.
584 Xilinx MicroBlaze microblaze-*-*
589 Xilinx MicroBlaze microblaze
592 * Multi-program debugging.
594 GDB now has support for multi-program (a.k.a. multi-executable or
595 multi-exec) debugging. This allows for debugging multiple inferiors
596 simultaneously each running a different program under the same GDB
597 session. See "Debugging Multiple Inferiors and Programs" in the
598 manual for more information. This implied some user visible changes
599 in the multi-inferior support. For example, "info inferiors" now
600 lists inferiors that are not running yet or that have exited
601 already. See also "New commands" and "New options" below.
603 * New tracing features
605 GDB's tracepoint facility now includes several new features:
607 ** Trace state variables
609 GDB tracepoints now include support for trace state variables, which
610 are variables managed by the target agent during a tracing
611 experiment. They are useful for tracepoints that trigger each
612 other, so for instance one tracepoint can count hits in a variable,
613 and then a second tracepoint has a condition that is true when the
614 count reaches a particular value. Trace state variables share the
615 $-syntax of GDB convenience variables, and can appear in both
616 tracepoint actions and condition expressions. Use the "tvariable"
617 command to create, and "info tvariables" to view; see "Trace State
618 Variables" in the manual for more detail.
622 GDB now includes an option for defining fast tracepoints, which
623 targets may implement more efficiently, such as by installing a jump
624 into the target agent rather than a trap instruction. The resulting
625 speedup can be by two orders of magnitude or more, although the
626 tradeoff is that some program locations on some target architectures
627 might not allow fast tracepoint installation, for instance if the
628 instruction to be replaced is shorter than the jump. To request a
629 fast tracepoint, use the "ftrace" command, with syntax identical to
630 the regular trace command.
632 ** Disconnected tracing
634 It is now possible to detach GDB from the target while it is running
635 a trace experiment, then reconnect later to see how the experiment
636 is going. In addition, a new variable disconnected-tracing lets you
637 tell the target agent whether to continue running a trace if the
638 connection is lost unexpectedly.
642 GDB now has the ability to save the trace buffer into a file, and
643 then use that file as a target, similarly to you can do with
644 corefiles. You can select trace frames, print data that was
645 collected in them, and use tstatus to display the state of the
646 tracing run at the moment that it was saved. To create a trace
647 file, use "tsave <filename>", and to use it, do "target tfile
650 ** Circular trace buffer
652 You can ask the target agent to handle the trace buffer as a
653 circular buffer, discarding the oldest trace frames to make room for
654 newer ones, by setting circular-trace-buffer to on. This feature may
655 not be available for all target agents.
660 The disassemble command, when invoked with two arguments, now requires
661 the arguments to be comma-separated.
664 The info variables command now displays variable definitions. Files
665 which only declare a variable are not shown.
668 The source command is now capable of sourcing Python scripts.
669 This feature is dependent on the debugger being build with Python
672 Related to this enhancement is also the introduction of a new command
673 "set script-extension" (see below).
675 * New commands (for set/show, see "New options" below)
677 record save [<FILENAME>]
678 Save a file (in core file format) containing the process record
679 execution log for replay debugging at a later time.
681 record restore <FILENAME>
682 Restore the process record execution log that was saved at an
683 earlier time, for replay debugging.
685 add-inferior [-copies <N>] [-exec <FILENAME>]
688 clone-inferior [-copies <N>] [ID]
689 Make a new inferior ready to execute the same program another
695 maint info program-spaces
696 List the program spaces loaded into GDB.
698 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
699 show remote interrupt-sequence
700 Allow the user to select one of ^C, a BREAK signal or BREAK-g
701 as the sequence to the remote target in order to interrupt the execution.
702 Ctrl-C is a default. Some system prefers BREAK which is high level of
703 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
704 Magic SysRq g. It is BREAK signal and character 'g'.
706 set remote interrupt-on-connect [on | off]
707 show remote interrupt-on-connect
708 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
709 remote target when gdb connects to it. This is needed when you debug
712 set remotebreak [on | off]
714 Deprecated. Use "set/show remote interrupt-sequence" instead.
716 tvariable $NAME [ = EXP ]
717 Create or modify a trace state variable.
720 List trace state variables and their values.
722 delete tvariable $NAME ...
723 Delete one or more trace state variables.
726 Evaluate the given expressions without collecting anything into the
727 trace buffer. (Valid in tracepoint actions only.)
729 ftrace FN / FILE:LINE / *ADDR
730 Define a fast tracepoint at the given function, line, or address.
732 * New expression syntax
734 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
735 GDB now parses 0b101010 identically with 42.
739 set follow-exec-mode new|same
740 show follow-exec-mode
741 Control whether GDB reuses the same inferior across an exec call or
742 creates a new one. This is useful to be able to restart the old
743 executable after the inferior having done an exec call.
745 set default-collect EXPR, ...
747 Define a list of expressions to be collected at each tracepoint.
748 This is a useful way to ensure essential items are not overlooked,
749 such as registers or a critical global variable.
751 set disconnected-tracing
752 show disconnected-tracing
753 If set to 1, the target is instructed to continue tracing if it
754 loses its connection to GDB. If 0, the target is to stop tracing
757 set circular-trace-buffer
758 show circular-trace-buffer
759 If set to on, the target is instructed to use a circular trace buffer
760 and discard the oldest trace frames instead of stopping the trace due
761 to a full trace buffer. If set to off, the trace stops when the buffer
762 fills up. Some targets may not support this.
764 set script-extension off|soft|strict
765 show script-extension
766 If set to "off", the debugger does not perform any script language
767 recognition, and all sourced files are assumed to be GDB scripts.
768 If set to "soft" (the default), files are sourced according to
769 filename extension, falling back to GDB scripts if the first
771 If set to "strict", files are sourced according to filename extension.
773 set ada trust-PAD-over-XVS on|off
774 show ada trust-PAD-over-XVS
775 If off, activate a workaround against a bug in the debugging information
776 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
777 the GCC sources for more information about the GNAT encoding and
778 PAD types in particular). It is always safe to set this option to
779 off, but this introduces a slight performance penalty. The default
782 * Python API Improvements
784 ** GDB provides the new class gdb.LazyString. This is useful in
785 some pretty-printing cases. The new method gdb.Value.lazy_string
786 provides a simple way to create objects of this type.
788 ** The fields returned by gdb.Type.fields now have an
789 `is_base_class' attribute.
791 ** The new method gdb.Type.range returns the range of an array type.
793 ** The new method gdb.parse_and_eval can be used to parse and
794 evaluate an expression.
799 Define a trace state variable.
802 Get the current value of a trace state variable.
805 Set desired tracing behavior upon disconnection.
808 Set the trace buffer to be linear or circular.
811 Get data about the tracepoints currently in use.
815 Process record now works correctly with hardware watchpoints.
817 Multiple bug fixes have been made to the mips-irix port, making it
818 much more reliable. In particular:
819 - Debugging threaded applications is now possible again. Previously,
820 GDB would hang while starting the program, or while waiting for
821 the program to stop at a breakpoint.
822 - Attaching to a running process no longer hangs.
823 - An error occurring while loading a core file has been fixed.
824 - Changing the value of the PC register now works again. This fixes
825 problems observed when using the "jump" command, or when calling
826 a function from GDB, or even when assigning a new value to $pc.
827 - With the "finish" and "return" commands, the return value for functions
828 returning a small array is now correctly printed.
829 - It is now possible to break on shared library code which gets executed
830 during a shared library init phase (code executed while executing
831 their .init section). Previously, the breakpoint would have no effect.
832 - GDB is now able to backtrace through the signal handler for
833 non-threaded programs.
835 PIE (Position Independent Executable) programs debugging is now supported.
836 This includes debugging execution of PIC (Position Independent Code) shared
837 libraries although for that, it should be possible to run such libraries as an
840 *** Changes in GDB 7.0
842 * GDB now has an interface for JIT compilation. Applications that
843 dynamically generate code can create symbol files in memory and register
844 them with GDB. For users, the feature should work transparently, and
845 for JIT developers, the interface is documented in the GDB manual in the
846 "JIT Compilation Interface" chapter.
848 * Tracepoints may now be conditional. The syntax is as for
849 breakpoints; either an "if" clause appended to the "trace" command,
850 or the "condition" command is available. GDB sends the condition to
851 the target for evaluation using the same bytecode format as is used
852 for tracepoint actions.
854 * The disassemble command now supports: an optional /r modifier, print the
855 raw instructions in hex as well as in symbolic form, and an optional /m
856 modifier to print mixed source+assembly.
858 * Process record and replay
860 In a architecture environment that supports ``process record and
861 replay'', ``process record and replay'' target can record a log of
862 the process execution, and replay it with both forward and reverse
865 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
866 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
867 set execution-direction {forward|reverse}, for targets that support
870 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
871 feature is available with a native GDB running on kernel version
874 * GDB now has support for multi-byte and wide character sets on the
875 target. Strings whose character type is wchar_t, char16_t, or
876 char32_t are now correctly printed. GDB supports wide- and unicode-
877 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
878 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
879 `printf'. This feature requires iconv to work properly; if your
880 system does not have a working iconv, GDB can use GNU libiconv. See
881 the installation instructions for more information.
883 * GDB now supports automatic retrieval of shared library files from
884 remote targets. To use this feature, specify a system root that begins
885 with the `remote:' prefix, either via the `set sysroot' command or via
886 the `--with-sysroot' configure-time option.
888 * "info sharedlibrary" now takes an optional regex of libraries to show,
889 and it now reports if a shared library has no debugging information.
891 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
892 now complete on file names.
894 * When completing in expressions, gdb will attempt to limit
895 completions to allowable structure or union fields, where appropriate.
896 For instance, consider:
898 # struct example { int f1; double f2; };
899 # struct example variable;
902 If the user types TAB at the end of this command line, the available
903 completions will be "f1" and "f2".
905 * Inlined functions are now supported. They show up in backtraces, and
906 the "step", "next", and "finish" commands handle them automatically.
908 * GDB now supports the token-splicing (##) and stringification (#)
909 operators when expanding macros. It also supports variable-arity
912 * GDB now supports inspecting extra signal information, exported by
913 the new $_siginfo convenience variable. The feature is currently
914 implemented on linux ARM, i386 and amd64.
916 * GDB can now display the VFP floating point registers and NEON vector
917 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
918 can provide these registers (requires Linux 2.6.30 or later). Remote
919 and simulator targets may also provide them.
924 Search memory for a sequence of bytes.
927 Turn off `+'/`-' protocol acknowledgments to permit more efficient
928 operation over reliable transport links. Use of this packet is
929 controlled by the `set remote noack-packet' command.
932 Kill the process with the specified process ID. Use this in preference
933 to `k' when multiprocess protocol extensions are supported.
936 Obtains additional operating system information
940 Read or write additional signal information.
942 * Removed remote protocol undocumented extension
944 An undocumented extension to the remote protocol's `S' stop reply
945 packet that permited the stub to pass a process id was removed.
946 Remote servers should use the `T' stop reply packet instead.
948 * GDB now supports multiple function calling conventions according to the
949 DWARF-2 DW_AT_calling_convention function attribute.
951 * The SH target utilizes the aforementioned change to distinguish between gcc
952 and Renesas calling convention. It also adds the new CLI commands
953 `set/show sh calling-convention'.
955 * GDB can now read compressed debug sections, as produced by GNU gold
956 with the --compress-debug-sections=zlib flag.
958 * 64-bit core files are now supported on AIX.
960 * Thread switching is now supported on Tru64.
962 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
963 which will be allocated using malloc later in program execution.
965 * The qXfer:libraries:read remote procotol packet now allows passing a
966 list of section offsets.
968 * On GNU/Linux, GDB can now attach to stopped processes. Several race
969 conditions handling signals delivered during attach or thread creation
970 have also been fixed.
972 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
973 From the user's standpoint, all unqualified instances of True and False
974 are treated as the standard definitions, regardless of context.
976 * GDB now parses C++ symbol and type names more flexibly. For
979 template<typename T> class C { };
982 GDB will now correctly handle all of:
984 ptype C<char const *>
986 ptype C<const char *>
989 * New features in the GDB remote stub, gdbserver
991 - The "--wrapper" command-line argument tells gdbserver to use a
992 wrapper program to launch programs for debugging.
994 - On PowerPC and S/390 targets, it is now possible to use a single
995 gdbserver executable to debug both 32-bit and 64-bit programs.
996 (This requires gdbserver itself to be built as a 64-bit executable.)
998 - gdbserver uses the new noack protocol mode for TCP connections to
999 reduce communications latency, if also supported and enabled in GDB.
1001 - Support for the sparc64-linux-gnu target is now included in
1004 - The amd64-linux build of gdbserver now supports debugging both
1005 32-bit and 64-bit programs.
1007 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1008 now support hardware watchpoints, and will use them automatically
1013 GDB now has support for scripting using Python. Whether this is
1014 available is determined at configure time.
1016 New GDB commands can now be written in Python.
1018 * Ada tasking support
1020 Ada tasks can now be inspected in GDB. The following commands have
1024 Print the list of Ada tasks.
1026 Print detailed information about task number N.
1028 Print the task number of the current task.
1030 Switch the context of debugging to task number N.
1032 * Support for user-defined prefixed commands. The "define" command can
1033 add new commands to existing prefixes, e.g. "target".
1035 * Multi-inferior, multi-process debugging.
1037 GDB now has generalized support for multi-inferior debugging. See
1038 "Debugging Multiple Inferiors" in the manual for more information.
1039 Although availability still depends on target support, the command
1040 set is more uniform now. The GNU/Linux specific multi-forks support
1041 has been migrated to this new framework. This implied some user
1042 visible changes; see "New commands" and also "Removed commands"
1045 * Target descriptions can now describe the target OS ABI. See the
1046 "Target Description Format" section in the user manual for more
1049 * Target descriptions can now describe "compatible" architectures
1050 to indicate that the target can execute applications for a different
1051 architecture in addition to those for the main target architecture.
1052 See the "Target Description Format" section in the user manual for
1055 * Multi-architecture debugging.
1057 GDB now includes general supports for debugging applications on
1058 hybrid systems that use more than one single processor architecture
1059 at the same time. Each such hybrid architecture still requires
1060 specific support to be added. The only hybrid architecture supported
1061 in this version of GDB is the Cell Broadband Engine.
1063 * GDB now supports integrated debugging of Cell/B.E. applications that
1064 use both the PPU and SPU architectures. To enable support for hybrid
1065 Cell/B.E. debugging, you need to configure GDB to support both the
1066 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1067 --enable-targets configure option.
1069 * Non-stop mode debugging.
1071 For some targets, GDB now supports an optional mode of operation in
1072 which you can examine stopped threads while other threads continue
1073 to execute freely. This is referred to as non-stop mode, with the
1074 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1075 section in the user manual for more information.
1077 To be able to support remote non-stop debugging, a remote stub needs
1078 to implement the non-stop mode remote protocol extensions, as
1079 described in the "Remote Non-Stop" section of the user manual. The
1080 GDB remote stub, gdbserver, has been adjusted to support these
1081 extensions on linux targets.
1083 * New commands (for set/show, see "New options" below)
1085 catch syscall [NAME(S) | NUMBER(S)]
1086 Catch system calls. Arguments, which should be names of system
1087 calls or their numbers, mean catch only those syscalls. Without
1088 arguments, every syscall will be caught. When the inferior issues
1089 any of the specified syscalls, GDB will stop and announce the system
1090 call, both when it is called and when its call returns. This
1091 feature is currently available with a native GDB running on the
1092 Linux Kernel, under the following architectures: x86, x86_64,
1093 PowerPC and PowerPC64.
1095 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1097 Search memory for a sequence of bytes.
1099 maint set python print-stack
1100 maint show python print-stack
1101 Show a stack trace when an error is encountered in a Python script.
1104 Invoke CODE by passing it to the Python interpreter.
1109 These allow macros to be defined, undefined, and listed
1113 Show operating system information about processes.
1116 List the inferiors currently under GDB's control.
1119 Switch focus to inferior number NUM.
1122 Detach from inferior number NUM.
1125 Kill inferior number NUM.
1129 set spu stop-on-load
1130 show spu stop-on-load
1131 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1133 set spu auto-flush-cache
1134 show spu auto-flush-cache
1135 Control whether to automatically flush the software-managed cache
1136 during Cell/B.E. debugging.
1138 set sh calling-convention
1139 show sh calling-convention
1140 Control the calling convention used when calling SH target functions.
1143 show debug timestamp
1144 Control display of timestamps with GDB debugging output.
1146 set disassemble-next-line
1147 show disassemble-next-line
1148 Control display of disassembled source lines or instructions when
1151 set remote noack-packet
1152 show remote noack-packet
1153 Set/show the use of remote protocol QStartNoAckMode packet. See above
1154 under "New remote packets."
1156 set remote query-attached-packet
1157 show remote query-attached-packet
1158 Control use of remote protocol `qAttached' (query-attached) packet.
1160 set remote read-siginfo-object
1161 show remote read-siginfo-object
1162 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1165 set remote write-siginfo-object
1166 show remote write-siginfo-object
1167 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1170 set remote reverse-continue
1171 show remote reverse-continue
1172 Control use of remote protocol 'bc' (reverse-continue) packet.
1174 set remote reverse-step
1175 show remote reverse-step
1176 Control use of remote protocol 'bs' (reverse-step) packet.
1178 set displaced-stepping
1179 show displaced-stepping
1180 Control displaced stepping mode. Displaced stepping is a way to
1181 single-step over breakpoints without removing them from the debuggee.
1182 Also known as "out-of-line single-stepping".
1185 show debug displaced
1186 Control display of debugging info for displaced stepping.
1188 maint set internal-error
1189 maint show internal-error
1190 Control what GDB does when an internal error is detected.
1192 maint set internal-warning
1193 maint show internal-warning
1194 Control what GDB does when an internal warning is detected.
1199 Use a wrapper program to launch programs for debugging.
1201 set multiple-symbols (all|ask|cancel)
1202 show multiple-symbols
1203 The value of this variable can be changed to adjust the debugger behavior
1204 when an expression or a breakpoint location contains an ambiguous symbol
1205 name (an overloaded function name, for instance).
1207 set breakpoint always-inserted
1208 show breakpoint always-inserted
1209 Keep breakpoints always inserted in the target, as opposed to inserting
1210 them when resuming the target, and removing them when the target stops.
1211 This option can improve debugger performance on slow remote targets.
1213 set arm fallback-mode (arm|thumb|auto)
1214 show arm fallback-mode
1215 set arm force-mode (arm|thumb|auto)
1217 These commands control how ARM GDB determines whether instructions
1218 are ARM or Thumb. The default for both settings is auto, which uses
1219 the current CPSR value for instructions without symbols; previous
1220 versions of GDB behaved as if "set arm fallback-mode arm".
1222 set disable-randomization
1223 show disable-randomization
1224 Standalone programs run with the virtual address space randomization enabled
1225 by default on some platforms. This option keeps the addresses stable across
1226 multiple debugging sessions.
1230 Control whether other threads are stopped or not when some thread hits
1235 Requests that asynchronous execution is enabled in the target, if available.
1236 In this case, it's possible to resume target in the background, and interact
1237 with GDB while the target is running. "show target-async" displays the
1238 current state of asynchronous execution of the target.
1240 set target-wide-charset
1241 show target-wide-charset
1242 The target-wide-charset is the name of the character set that GDB
1243 uses when printing characters whose type is wchar_t.
1245 set tcp auto-retry (on|off)
1247 set tcp connect-timeout
1248 show tcp connect-timeout
1249 These commands allow GDB to retry failed TCP connections to a remote stub
1250 with a specified timeout period; this is useful if the stub is launched
1251 in parallel with GDB but may not be ready to accept connections immediately.
1253 set libthread-db-search-path
1254 show libthread-db-search-path
1255 Control list of directories which GDB will search for appropriate
1258 set schedule-multiple (on|off)
1259 show schedule-multiple
1260 Allow GDB to resume all threads of all processes or only threads of
1261 the current process.
1265 Use more aggressive caching for accesses to the stack. This improves
1266 performance of remote debugging (particularly backtraces) without
1267 affecting correctness.
1269 set interactive-mode (on|off|auto)
1270 show interactive-mode
1271 Control whether GDB runs in interactive mode (on) or not (off).
1272 When in interactive mode, GDB waits for the user to answer all
1273 queries. Otherwise, GDB does not wait and assumes the default
1274 answer. When set to auto (the default), GDB determines which
1275 mode to use based on the stdin settings.
1280 For program forks, this is replaced by the new more generic `info
1281 inferiors' command. To list checkpoints, you can still use the
1282 `info checkpoints' command, which was an alias for the `info forks'
1286 Replaced by the new `inferior' command. To switch between
1287 checkpoints, you can still use the `restart' command, which was an
1288 alias for the `fork' command.
1291 This is removed, since some targets don't have a notion of
1292 processes. To switch between processes, you can still use the
1293 `inferior' command using GDB's own inferior number.
1296 For program forks, this is replaced by the new more generic `kill
1297 inferior' command. To delete a checkpoint, you can still use the
1298 `delete checkpoint' command, which was an alias for the `delete
1302 For program forks, this is replaced by the new more generic `detach
1303 inferior' command. To detach a checkpoint, you can still use the
1304 `detach checkpoint' command, which was an alias for the `detach
1307 * New native configurations
1309 x86/x86_64 Darwin i[34567]86-*-darwin*
1311 x86_64 MinGW x86_64-*-mingw*
1315 Lattice Mico32 lm32-*
1316 x86 DICOS i[34567]86-*-dicos*
1317 x86_64 DICOS x86_64-*-dicos*
1320 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1321 (mingw32ce) debugging.
1327 These commands were actually not implemented on any target.
1329 *** Changes in GDB 6.8
1331 * New native configurations
1333 NetBSD/hppa hppa*-*netbsd*
1334 Xtensa GNU/Linux xtensa*-*-linux*
1338 NetBSD/hppa hppa*-*-netbsd*
1339 Xtensa GNU/Lunux xtensa*-*-linux*
1341 * Change in command line behavior -- corefiles vs. process ids.
1343 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1344 attaching to process NUMBER fails, GDB no longer attempts to open a
1345 core file named NUMBER. Attaching to a program using the -c option
1346 is no longer supported. Instead, use the '-p' or '--pid' options.
1348 * GDB can now be built as a native debugger for debugging Windows x86
1349 (mingw32) Portable Executable (PE) programs.
1351 * Pending breakpoints no longer change their number when their address
1354 * GDB now supports breakpoints with multiple locations,
1355 including breakpoints on C++ constructors, inside C++ templates,
1356 and in inlined functions.
1358 * GDB's ability to debug optimized code has been improved. GDB more
1359 accurately identifies function bodies and lexical blocks that occupy
1360 more than one contiguous range of addresses.
1362 * Target descriptions can now describe registers for PowerPC.
1364 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1365 registers on PowerPC targets.
1367 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1368 targets even when the libthread_db library is not available.
1370 * The GDB remote stub, gdbserver, now supports the new file transfer
1371 commands (remote put, remote get, and remote delete).
1373 * The GDB remote stub, gdbserver, now supports run and attach in
1374 extended-remote mode.
1376 * hppa*64*-*-hpux11* target broken
1377 The debugger is unable to start a program and fails with the following
1378 error: "Error trying to get information about dynamic linker".
1379 The gdb-6.7 release is also affected.
1381 * GDB now supports the --enable-targets= configure option to allow
1382 building a single GDB executable that supports multiple remote
1383 target architectures.
1385 * GDB now supports debugging C and C++ programs which use the
1386 Decimal Floating Point extension. In addition, the PowerPC target
1387 now has a set of pseudo-registers to inspect decimal float values
1388 stored in two consecutive float registers.
1390 * The -break-insert MI command can optionally create pending
1393 * Improved support for debugging Ada
1394 Many improvements to the Ada language support have been made. These
1396 - Better support for Ada2005 interface types
1397 - Improved handling of arrays and slices in general
1398 - Better support for Taft-amendment types
1399 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1401 - Improved command completion in Ada
1404 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1409 set print frame-arguments (all|scalars|none)
1410 show print frame-arguments
1411 The value of this variable can be changed to control which argument
1412 values should be printed by the debugger when displaying a frame.
1417 Transfer files to and from a remote target, and delete remote files.
1424 Transfer files to and from a remote target, and delete remote files.
1426 * New remote packets
1433 Open, close, read, write, and delete files on the remote system.
1436 Attach to an existing process on the remote system, in extended-remote
1440 Run a new process on the remote system, in extended-remote mode.
1442 *** Changes in GDB 6.7
1444 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1445 bfd, libiberty and opcodes, as revealed by static analysis donated by
1446 Coverity, Inc. (http://scan.coverity.com).
1448 * When looking up multiply-defined global symbols, GDB will now prefer the
1449 symbol definition in the current shared library if it was built using the
1450 -Bsymbolic linker option.
1452 * When the Text User Interface (TUI) is not configured, GDB will now
1453 recognize the -tui command-line option and print a message that the TUI
1456 * The GDB remote stub, gdbserver, now has lower overhead for high
1457 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1459 * GDB for MIPS targets now autodetects whether a remote target provides
1460 32-bit or 64-bit register values.
1462 * Support for C++ member pointers has been improved.
1464 * GDB now understands XML target descriptions, which specify the
1465 target's overall architecture. GDB can read a description from
1466 a local file or over the remote serial protocol.
1468 * Vectors of single-byte data use a new integer type which is not
1469 automatically displayed as character or string data.
1471 * The /s format now works with the print command. It displays
1472 arrays of single-byte integers and pointers to single-byte integers
1475 * Target descriptions can now describe target-specific registers,
1476 for architectures which have implemented the support (currently
1477 only ARM, M68K, and MIPS).
1479 * GDB and the GDB remote stub, gdbserver, now support the XScale
1482 * The GDB remote stub, gdbserver, has been updated to support
1483 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1484 has been rewritten to use the standard GDB remote protocol.
1486 * GDB can now step into C++ functions which are called through thunks.
1488 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1490 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1491 layout. It also supports a TextSeg= and DataSeg= response when only
1492 segment base addresses (rather than offsets) are available.
1494 * The /i format now outputs any trailing branch delay slot instructions
1495 immediately following the last instruction within the count specified.
1497 * The GDB remote protocol "T" stop reply packet now supports a
1498 "library" response. Combined with the new "qXfer:libraries:read"
1499 packet, this response allows GDB to debug shared libraries on targets
1500 where the operating system manages the list of loaded libraries (e.g.
1501 Windows and SymbianOS).
1503 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1504 (DLLs) on Windows and Windows CE targets.
1506 * GDB now supports a faster verification that a .debug file matches its binary
1507 according to its build-id signature, if the signature is present.
1513 Enable or disable hardware flow control (RTS/CTS) on the serial port
1514 when debugging using remote targets.
1516 set mem inaccessible-by-default
1517 show mem inaccessible-by-default
1518 If the target supplies a memory map, for instance via the remote
1519 protocol's "qXfer:memory-map:read" packet, setting this variable
1520 prevents GDB from accessing memory outside the memory map. This
1521 is useful for targets with memory mapped registers or which react
1522 badly to accesses of unmapped address space.
1524 set breakpoint auto-hw
1525 show breakpoint auto-hw
1526 If the target supplies a memory map, for instance via the remote
1527 protocol's "qXfer:memory-map:read" packet, setting this variable
1528 lets GDB use hardware breakpoints automatically for memory regions
1529 where it can not use software breakpoints. This covers both the
1530 "break" command and internal breakpoints used for other commands
1531 including "next" and "finish".
1534 catch exception unhandled
1535 Stop the program execution when Ada exceptions are raised.
1538 Stop the program execution when an Ada assertion failed.
1542 Set an alternate system root for target files. This is a more
1543 general version of "set solib-absolute-prefix", which is now
1544 an alias to "set sysroot".
1547 Provide extended SPU facility status information. This set of
1548 commands is available only when debugging the Cell/B.E. SPU
1551 * New native configurations
1553 OpenBSD/sh sh*-*openbsd*
1556 unset tdesc filename
1558 Use the specified local file as an XML target description, and do
1559 not query the target for its built-in description.
1563 OpenBSD/sh sh*-*-openbsd*
1564 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1565 Toshiba Media Processor mep-elf
1567 * New remote packets
1570 Ignore the specified signals; pass them directly to the debugged program
1571 without stopping other threads or reporting them to GDB.
1573 qXfer:features:read:
1574 Read an XML target description from the target, which describes its
1579 Read or write contents of an spufs file on the target system. These
1580 packets are available only on the Cell/B.E. SPU architecture.
1582 qXfer:libraries:read:
1583 Report the loaded shared libraries. Combined with new "T" packet
1584 response, this packet allows GDB to debug shared libraries on
1585 targets where the operating system manages the list of loaded
1586 libraries (e.g. Windows and SymbianOS).
1590 Support for these obsolete configurations has been removed.
1598 i[34567]86-*-lynxos*
1599 i[34567]86-*-netware*
1600 i[34567]86-*-sco3.2v5*
1601 i[34567]86-*-sco3.2v4*
1603 i[34567]86-*-sysv4.2*
1606 i[34567]86-*-unixware2*
1607 i[34567]86-*-unixware*
1616 * Other removed features
1623 Various m68k-only ROM monitors.
1630 Various Renesas ROM monitors and debugging interfaces for SH and
1635 Support for a Macraigor serial interface to on-chip debugging.
1636 GDB does not directly support the newer parallel or USB
1641 A debug information format. The predecessor to DWARF 2 and
1642 DWARF 3, which are still supported.
1644 Support for the HP aCC compiler on HP-UX/PA-RISC
1646 SOM-encapsulated symbolic debugging information, automatic
1647 invocation of pxdb, and the aCC custom C++ ABI. This does not
1648 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1649 with aCC can still be debugged on an assembly level.
1651 MIPS ".pdr" sections
1653 A MIPS-specific format used to describe stack frame layout
1654 in debugging information.
1658 GDB could work with an older version of Guile to debug
1659 the interpreter and Scheme programs running in it.
1661 set mips stack-arg-size
1662 set mips saved-gpreg-size
1664 Use "set mips abi" to control parameter passing for MIPS.
1666 *** Changes in GDB 6.6
1671 Cell Broadband Engine SPU spu-elf
1673 * GDB can now be configured as a cross-debugger targeting native Windows
1674 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1675 running on a Windows system over TCP/IP to debug Windows programs.
1677 * The GDB remote stub, gdbserver, has been updated to support Windows and
1678 Cygwin debugging. Both single-threaded and multi-threaded programs are
1681 * The "set trust-readonly-sections" command works again. This command was
1682 broken in GDB 6.3, 6.4, and 6.5.
1684 * The "load" command now supports writing to flash memory, if the remote
1685 stub provides the required support.
1687 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1688 longer requires symbolic debug information (e.g. DWARF-2).
1693 unset substitute-path
1694 show substitute-path
1695 Manage a list of substitution rules that GDB uses to rewrite the name
1696 of the directories where the sources are located. This can be useful
1697 for instance when the sources were moved to a different location
1698 between compilation and debugging.
1702 Print each CLI command as it is executed. Each command is prefixed with
1703 a number of `+' symbols representing the nesting depth.
1704 The source command now has a `-v' option to enable the same feature.
1708 The ARM Demon monitor support (RDP protocol, "target rdp").
1710 Kernel Object Display, an embedded debugging feature which only worked with
1711 an obsolete version of Cisco IOS.
1713 The 'set download-write-size' and 'show download-write-size' commands.
1715 * New remote packets
1718 Tell a stub about GDB client features, and request remote target features.
1719 The first feature implemented is PacketSize, which allows the target to
1720 specify the size of packets it can handle - to minimize the number of
1721 packets required and improve performance when connected to a remote
1725 Fetch an OS auxilliary vector from the remote stub. This packet is a
1726 more efficient replacement for qPart:auxv:read.
1728 qXfer:memory-map:read:
1729 Fetch a memory map from the remote stub, including information about
1730 RAM, ROM, and flash memory devices.
1735 Erase and program a flash memory device.
1737 * Removed remote packets
1740 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1741 used it, and only gdbserver implemented it.
1743 *** Changes in GDB 6.5
1747 Renesas M32C/M16C m32c-elf
1749 Morpho Technologies ms1 ms1-elf
1753 init-if-undefined Initialize a convenience variable, but
1754 only if it doesn't already have a value.
1756 The following commands are presently only implemented for native GNU/Linux:
1758 checkpoint Save a snapshot of the program state.
1760 restart <n> Return the program state to a
1761 previously saved state.
1763 info checkpoints List currently saved checkpoints.
1765 delete-checkpoint <n> Delete a previously saved checkpoint.
1767 set|show detach-on-fork Tell gdb whether to detach from a newly
1768 forked process, or to keep debugging it.
1770 info forks List forks of the user program that
1771 are available to be debugged.
1773 fork <n> Switch to debugging one of several
1774 forks of the user program that are
1775 available to be debugged.
1777 delete-fork <n> Delete a fork from the list of forks
1778 that are available to be debugged (and
1779 kill the forked process).
1781 detach-fork <n> Delete a fork from the list of forks
1782 that are available to be debugged (and
1783 allow the process to continue).
1787 Morpho Technologies ms2 ms1-elf
1789 * Improved Windows host support
1791 GDB now builds as a cross debugger hosted on i686-mingw32, including
1792 native console support, and remote communications using either
1793 network sockets or serial ports.
1795 * Improved Modula-2 language support
1797 GDB can now print most types in the Modula-2 syntax. This includes:
1798 basic types, set types, record types, enumerated types, range types,
1799 pointer types and ARRAY types. Procedure var parameters are correctly
1800 printed and hexadecimal addresses and character constants are also
1801 written in the Modula-2 syntax. Best results can be obtained by using
1802 GNU Modula-2 together with the -gdwarf-2 command line option.
1806 The ARM rdi-share module.
1808 The Netware NLM debug server.
1810 *** Changes in GDB 6.4
1812 * New native configurations
1814 OpenBSD/arm arm*-*-openbsd*
1815 OpenBSD/mips64 mips64-*-openbsd*
1819 Morpho Technologies ms1 ms1-elf
1821 * New command line options
1823 --batch-silent As for --batch, but totally silent.
1824 --return-child-result The debugger will exist with the same value
1825 the child (debugged) program exited with.
1826 --eval-command COMMAND, -ex COMMAND
1827 Execute a single GDB CLI command. This may be
1828 specified multiple times and in conjunction
1829 with the --command (-x) option.
1831 * Deprecated commands removed
1833 The following commands, that were deprecated in 2000, have been
1837 set|show arm disassembly-flavor set|show arm disassembler
1838 othernames set arm disassembler
1839 set|show remotedebug set|show debug remote
1840 set|show archdebug set|show debug arch
1841 set|show eventdebug set|show debug event
1844 * New BSD user-level threads support
1846 It is now possible to debug programs using the user-level threads
1847 library on OpenBSD and FreeBSD. Currently supported (target)
1850 FreeBSD/amd64 x86_64-*-freebsd*
1851 FreeBSD/i386 i386-*-freebsd*
1852 OpenBSD/i386 i386-*-openbsd*
1854 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1855 are not yet supported.
1857 * New support for Matsushita MN10300 w/sim added
1858 (Work in progress). mn10300-elf.
1860 * REMOVED configurations and files
1862 VxWorks and the XDR protocol *-*-vxworks
1863 Motorola MCORE mcore-*-*
1864 National Semiconductor NS32000 ns32k-*-*
1866 * New "set print array-indexes" command
1868 After turning this setting "on", GDB prints the index of each element
1869 when displaying arrays. The default is "off" to preserve the previous
1872 * VAX floating point support
1874 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1876 * User-defined command support
1878 In addition to using $arg0..$arg9 for argument passing, it is now possible
1879 to use $argc to determine now many arguments have been passed. See the
1880 section on user-defined commands in the user manual for more information.
1882 *** Changes in GDB 6.3:
1884 * New command line option
1886 GDB now accepts -l followed by a number to set the timeout for remote
1889 * GDB works with GCC -feliminate-dwarf2-dups
1891 GDB now supports a more compact representation of DWARF-2 debug
1892 information using DW_FORM_ref_addr references. These are produced
1893 by GCC with the option -feliminate-dwarf2-dups and also by some
1894 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1895 to use -feliminate-dwarf2-dups.
1897 * Internationalization
1899 When supported by the host system, GDB will be built with
1900 internationalization (libintl). The task of marking up the sources is
1901 continued, we're looking forward to our first translation.
1905 Initial support for debugging programs compiled with the GNAT
1906 implementation of the Ada programming language has been integrated
1907 into GDB. In this release, support is limited to expression evaluation.
1909 * New native configurations
1911 GNU/Linux/m32r m32r-*-linux-gnu
1915 GDB's remote protocol now includes support for the 'p' packet. This
1916 packet is used to fetch individual registers from a remote inferior.
1918 * END-OF-LIFE registers[] compatibility module
1920 GDB's internal register infrastructure has been completely rewritten.
1921 The new infrastructure making possible the implementation of key new
1922 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1925 GDB 6.3 will be the last release to include the the registers[]
1926 compatibility module that allowed out-of-date configurations to
1927 continue to work. This change directly impacts the following
1937 powerpc bdm protocol
1939 Unless there is activity to revive these configurations, they will be
1940 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1942 * OBSOLETE configurations and files
1944 Configurations that have been declared obsolete in this release have
1945 been commented out. Unless there is activity to revive these
1946 configurations, the next release of GDB will have their sources
1947 permanently REMOVED.
1956 *** Changes in GDB 6.2.1:
1958 * MIPS `break main; run' gave an heuristic-fence-post warning
1960 When attempting to run even a simple program, a warning about
1961 heuristic-fence-post being hit would be reported. This problem has
1964 * MIPS IRIX 'long double' crashed GDB
1966 When examining a long double variable, GDB would get a segmentation
1967 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1968 IRIX long double values).
1972 A bug in the VAX stack code was causing problems with the "next"
1973 command. This problem has been fixed.
1975 *** Changes in GDB 6.2:
1977 * Fix for ``many threads''
1979 On GNU/Linux systems that use the NPTL threads library, a program
1980 rapidly creating and deleting threads would confuse GDB leading to the
1983 ptrace: No such process.
1984 thread_db_get_info: cannot get thread info: generic error
1986 This problem has been fixed.
1988 * "-async" and "-noasync" options removed.
1990 Support for the broken "-noasync" option has been removed (it caused
1993 * New ``start'' command.
1995 This command runs the program until the begining of the main procedure.
1997 * New BSD Kernel Data Access Library (libkvm) interface
1999 Using ``target kvm'' it is now possible to debug kernel core dumps and
2000 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2001 platforms. Currently supported (native-only) configurations are:
2003 FreeBSD/amd64 x86_64-*-freebsd*
2004 FreeBSD/i386 i?86-*-freebsd*
2005 NetBSD/i386 i?86-*-netbsd*
2006 NetBSD/m68k m68*-*-netbsd*
2007 NetBSD/sparc sparc-*-netbsd*
2008 OpenBSD/amd64 x86_64-*-openbsd*
2009 OpenBSD/i386 i?86-*-openbsd*
2010 OpenBSD/m68k m68*-openbsd*
2011 OpenBSD/sparc sparc-*-openbsd*
2013 * Signal trampoline code overhauled
2015 Many generic problems with GDB's signal handling code have been fixed.
2016 These include: backtraces through non-contiguous stacks; recognition
2017 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2018 call; backtrace through a signal trampoline; step into and out of
2019 signal handlers; and single-stepping in the signal trampoline.
2021 Please note that kernel bugs are a limiting factor here. These
2022 features have been shown to work on an s390 GNU/Linux system that
2023 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2025 * Cygwin support for DWARF 2 added.
2027 * New native configurations
2029 GNU/Linux/hppa hppa*-*-linux*
2030 OpenBSD/hppa hppa*-*-openbsd*
2031 OpenBSD/m68k m68*-*-openbsd*
2032 OpenBSD/m88k m88*-*-openbsd*
2033 OpenBSD/powerpc powerpc-*-openbsd*
2034 NetBSD/vax vax-*-netbsd*
2035 OpenBSD/vax vax-*-openbsd*
2037 * END-OF-LIFE frame compatibility module
2039 GDB's internal frame infrastructure has been completely rewritten.
2040 The new infrastructure making it possible to support key new features
2041 including DWARF 2 Call Frame Information. To aid in the task of
2042 migrating old configurations to this new infrastructure, a
2043 compatibility module, that allowed old configurations to continue to
2044 work, was also included.
2046 GDB 6.2 will be the last release to include this frame compatibility
2047 module. This change directly impacts the following configurations:
2057 Unless there is activity to revive these configurations, they will be
2058 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2060 * REMOVED configurations and files
2062 Sun 3, running SunOS 3 m68*-*-sunos3*
2063 Sun 3, running SunOS 4 m68*-*-sunos4*
2064 Sun 2, running SunOS 3 m68000-*-sunos3*
2065 Sun 2, running SunOS 4 m68000-*-sunos4*
2066 Motorola 680x0 running LynxOS m68*-*-lynxos*
2067 AT&T 3b1/Unix pc m68*-att-*
2068 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2069 decstation mips-dec-* mips-little-*
2070 riscos mips-*-riscos* mips-*-sysv*
2071 sonymips mips-sony-*
2072 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2074 *** Changes in GDB 6.1.1:
2076 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2078 The TUI (Text-mode User Interface) is now built as part of a default
2079 GDB configuration. It is enabled by either selecting the TUI with the
2080 command line option "-i=tui" or by running the separate "gdbtui"
2081 program. For more information on the TUI, see the manual "Debugging
2084 * Pending breakpoint support (also included in GDB 6.1)
2086 Support has been added to allow you to specify breakpoints in shared
2087 libraries that have not yet been loaded. If a breakpoint location
2088 cannot be found, and the "breakpoint pending" option is set to auto,
2089 GDB queries you if you wish to make the breakpoint pending on a future
2090 shared-library load. If and when GDB resolves the breakpoint symbol,
2091 the pending breakpoint is removed as one or more regular breakpoints
2094 Pending breakpoints are very useful for GCJ Java debugging.
2096 * Fixed ISO-C build problems
2098 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2099 non ISO-C code that stopped them being built using a more strict ISO-C
2100 compiler (e.g., IBM's C compiler).
2102 * Fixed build problem on IRIX 5
2104 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2105 wasn't able to compile compile on an IRIX 5 system.
2107 * Added execute permission to gdb/gdbserver/configure
2109 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2110 permission. This bug would cause configure to fail on a number of
2111 systems (Solaris, IRIX). Ref: server/519.
2113 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2115 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2116 has been updated to use constant array sizes.
2118 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2120 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2121 its generated DWARF Call Frame Info. This encoding was causing GDB to
2122 panic, that panic has been fixed. Ref: gdb/1628.
2124 * Fixed a problem when examining parameters in shared library code.
2126 When examining parameters in optimized shared library code generated
2127 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2128 not available''. GDB now correctly displays the variable's value.
2130 *** Changes in GDB 6.1:
2132 * Removed --with-mmalloc
2134 Support for the mmalloc memory manager has been removed, as it
2135 conflicted with the internal gdb byte cache.
2137 * Changes in AMD64 configurations
2139 The AMD64 target now includes the %cs and %ss registers. As a result
2140 the AMD64 remote protocol has changed; this affects the floating-point
2141 and SSE registers. If you rely on those registers for your debugging,
2142 you should upgrade gdbserver on the remote side.
2144 * Revised SPARC target
2146 The SPARC target has been completely revised, incorporating the
2147 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2148 support for LynxOS and SunOS 4 has been dropped. Calling functions
2149 from within GDB on operating systems with a non-executable stack
2150 (Solaris, OpenBSD) now works.
2154 GDB has a new C++ demangler which does a better job on the mangled
2155 names generated by current versions of g++. It also runs faster, so
2156 with this and other changes gdb should now start faster on large C++
2159 * DWARF 2 Location Expressions
2161 GDB support for location expressions has been extended to support function
2162 arguments and frame bases. Older versions of GDB could crash when they
2165 * C++ nested types and namespaces
2167 GDB's support for nested types and namespaces in C++ has been
2168 improved, especially if you use the DWARF 2 debugging format. (This
2169 is the default for recent versions of GCC on most platforms.)
2170 Specifically, if you have a class "Inner" defined within a class or
2171 namespace "Outer", then GDB realizes that the class's name is
2172 "Outer::Inner", not simply "Inner". This should greatly reduce the
2173 frequency of complaints about not finding RTTI symbols. In addition,
2174 if you are stopped at inside of a function defined within a namespace,
2175 GDB modifies its name lookup accordingly.
2177 * New native configurations
2179 NetBSD/amd64 x86_64-*-netbsd*
2180 OpenBSD/amd64 x86_64-*-openbsd*
2181 OpenBSD/alpha alpha*-*-openbsd*
2182 OpenBSD/sparc sparc-*-openbsd*
2183 OpenBSD/sparc64 sparc64-*-openbsd*
2185 * New debugging protocols
2187 M32R with SDI protocol m32r-*-elf*
2189 * "set prompt-escape-char" command deleted.
2191 The command "set prompt-escape-char" has been deleted. This command,
2192 and its very obscure effet on GDB's prompt, was never documented,
2193 tested, nor mentioned in the NEWS file.
2195 * OBSOLETE configurations and files
2197 Configurations that have been declared obsolete in this release have
2198 been commented out. Unless there is activity to revive these
2199 configurations, the next release of GDB will have their sources
2200 permanently REMOVED.
2202 Sun 3, running SunOS 3 m68*-*-sunos3*
2203 Sun 3, running SunOS 4 m68*-*-sunos4*
2204 Sun 2, running SunOS 3 m68000-*-sunos3*
2205 Sun 2, running SunOS 4 m68000-*-sunos4*
2206 Motorola 680x0 running LynxOS m68*-*-lynxos*
2207 AT&T 3b1/Unix pc m68*-att-*
2208 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2209 decstation mips-dec-* mips-little-*
2210 riscos mips-*-riscos* mips-*-sysv*
2211 sonymips mips-sony-*
2212 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2214 * REMOVED configurations and files
2216 SGI Irix-4.x mips-sgi-irix4 or iris4
2217 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2218 Z8000 simulator z8k-zilog-none or z8ksim
2219 Matsushita MN10200 w/simulator mn10200-*-*
2220 H8/500 simulator h8500-hitachi-hms or h8500hms
2221 HP/PA running BSD hppa*-*-bsd*
2222 HP/PA running OSF/1 hppa*-*-osf*
2223 HP/PA Pro target hppa*-*-pro*
2224 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2225 386BSD i[3456]86-*-bsd*
2226 Sequent family i[3456]86-sequent-sysv4*
2227 i[3456]86-sequent-sysv*
2228 i[3456]86-sequent-bsd*
2229 SPARC running LynxOS sparc-*-lynxos*
2230 SPARC running SunOS 4 sparc-*-sunos4*
2231 Tsqware Sparclet sparclet-*-*
2232 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2234 *** Changes in GDB 6.0:
2238 Support for debugging the Objective-C programming language has been
2239 integrated into GDB.
2241 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2243 DWARF 2's Call Frame Information makes available compiler generated
2244 information that more exactly describes the program's run-time stack.
2245 By using this information, GDB is able to provide more robust stack
2248 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2249 have been updated to use a new backtrace mechanism which includes
2250 DWARF 2 CFI support.
2254 GDB's remote protocol has been extended to include support for hosted
2255 file I/O (where the remote target uses GDB's file system). See GDB's
2256 remote protocol documentation for details.
2258 * All targets using the new architecture framework.
2260 All of GDB's targets have been updated to use the new internal
2261 architecture framework. The way is now open for future GDB releases
2262 to include cross-architecture native debugging support (i386 on amd64,
2265 * GNU/Linux's Thread Local Storage (TLS)
2267 GDB now includes support for for the GNU/Linux implementation of
2268 per-thread variables.
2270 * GNU/Linux's Native POSIX Thread Library (NPTL)
2272 GDB's thread code has been updated to work with either the new
2273 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2275 * Separate debug info.
2277 GDB, in conjunction with BINUTILS, now supports a mechanism for
2278 automatically loading debug information from a separate file. Instead
2279 of shipping full debug and non-debug versions of system libraries,
2280 system integrators can now instead ship just the stripped libraries
2281 and optional debug files.
2283 * DWARF 2 Location Expressions
2285 DWARF 2 Location Expressions allow the compiler to more completely
2286 describe the location of variables (even in optimized code) to the
2289 GDB now includes preliminary support for location expressions (support
2290 for DW_OP_piece is still missing).
2294 A number of long standing bugs that caused GDB to die while starting a
2295 Java application have been fixed. GDB's Java support is now
2296 considered "useable".
2298 * GNU/Linux support for fork, vfork, and exec.
2300 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2301 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2304 * GDB supports logging output to a file
2306 There are two new commands, "set logging" and "show logging", which can be
2307 used to capture GDB's output to a file.
2309 * The meaning of "detach" has changed for gdbserver
2311 The "detach" command will now resume the application, as documented. To
2312 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2315 * d10v, m68hc11 `regs' command deprecated
2317 The `info registers' command has been updated so that it displays the
2318 registers using a format identical to the old `regs' command.
2322 A new command, "maint set profile on/off", has been added. This command can
2323 be used to enable or disable profiling while running GDB, to profile a
2324 session or a set of commands. In addition there is a new configure switch,
2325 "--enable-profiling", which will cause GDB to be compiled with profiling
2326 data, for more informative profiling results.
2328 * Default MI syntax changed to "mi2".
2330 The default MI (machine interface) syntax, enabled by the command line
2331 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2332 "mi1", can be enabled by specifying the option "-i=mi1".
2334 Support for the original "mi0" syntax (included in GDB 5.0) has been
2337 Fix for gdb/192: removed extraneous space when displaying frame level.
2338 Fix for gdb/672: update changelist is now output in mi list format.
2339 Fix for gdb/702: a -var-assign that updates the value now shows up
2340 in a subsequent -var-update.
2342 * New native configurations.
2344 FreeBSD/amd64 x86_64-*-freebsd*
2346 * Multi-arched targets.
2348 HP/PA HPUX11 hppa*-*-hpux*
2349 Renesas M32R/D w/simulator m32r-*-elf*
2351 * OBSOLETE configurations and files
2353 Configurations that have been declared obsolete in this release have
2354 been commented out. Unless there is activity to revive these
2355 configurations, the next release of GDB will have their sources
2356 permanently REMOVED.
2358 Z8000 simulator z8k-zilog-none or z8ksim
2359 Matsushita MN10200 w/simulator mn10200-*-*
2360 H8/500 simulator h8500-hitachi-hms or h8500hms
2361 HP/PA running BSD hppa*-*-bsd*
2362 HP/PA running OSF/1 hppa*-*-osf*
2363 HP/PA Pro target hppa*-*-pro*
2364 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2365 Sequent family i[3456]86-sequent-sysv4*
2366 i[3456]86-sequent-sysv*
2367 i[3456]86-sequent-bsd*
2368 Tsqware Sparclet sparclet-*-*
2369 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2371 * REMOVED configurations and files
2374 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2375 IBM AIX PS/2 i[3456]86-*-aix
2376 i386 running Mach 3.0 i[3456]86-*-mach3*
2377 i386 running Mach i[3456]86-*-mach*
2378 i386 running OSF/1 i[3456]86-*osf1mk*
2379 HP/Apollo 68k Family m68*-apollo*-sysv*,
2381 m68*-hp-bsd*, m68*-hp-hpux*
2382 Argonaut Risc Chip (ARC) arc-*-*
2383 Mitsubishi D30V d30v-*-*
2384 Fujitsu FR30 fr30-*-elf*
2385 OS/9000 i[34]86-*-os9k
2386 I960 with MON960 i960-*-coff
2388 * MIPS $fp behavior changed
2390 The convenience variable $fp, for the MIPS, now consistently returns
2391 the address of the current frame's base. Previously, depending on the
2392 context, $fp could refer to either $sp or the current frame's base
2393 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2394 The GNU Source-Level Debugger''.
2396 *** Changes in GDB 5.3:
2398 * GNU/Linux shared library multi-threaded performance improved.
2400 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2401 `/proc', in preference to `ptrace' for memory reads. This may result
2402 in an improvement in the start-up time of multi-threaded, shared
2403 library applications when run under GDB. One GDB user writes: ``loads
2404 shared libs like mad''.
2406 * ``gdbserver'' now supports multi-threaded applications on some targets
2408 Support for debugging multi-threaded applications which use
2409 the GNU/Linux LinuxThreads package has been added for
2410 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2411 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2413 * GDB now supports C/C++ preprocessor macros.
2415 GDB now expands preprocessor macro invocations in C/C++ expressions,
2416 and provides various commands for showing macro definitions and how
2419 The new command `macro expand EXPRESSION' expands any macro
2420 invocations in expression, and shows the result.
2422 The new command `show macro MACRO-NAME' shows the definition of the
2423 macro named MACRO-NAME, and where it was defined.
2425 Most compilers don't include information about macros in the debugging
2426 information by default. In GCC 3.1, for example, you need to compile
2427 your program with the options `-gdwarf-2 -g3'. If the macro
2428 information is present in the executable, GDB will read it.
2430 * Multi-arched targets.
2432 DEC Alpha (partial) alpha*-*-*
2433 DEC VAX (partial) vax-*-*
2435 National Semiconductor NS32000 (partial) ns32k-*-*
2436 Motorola 68000 (partial) m68k-*-*
2437 Motorola MCORE mcore-*-*
2441 Fujitsu FRV architecture added by Red Hat frv*-*-*
2444 * New native configurations
2446 Alpha NetBSD alpha*-*-netbsd*
2447 SH NetBSD sh*-*-netbsdelf*
2448 MIPS NetBSD mips*-*-netbsd*
2449 UltraSPARC NetBSD sparc64-*-netbsd*
2451 * OBSOLETE configurations and files
2453 Configurations that have been declared obsolete in this release have
2454 been commented out. Unless there is activity to revive these
2455 configurations, the next release of GDB will have their sources
2456 permanently REMOVED.
2458 Mitsubishi D30V d30v-*-*
2459 OS/9000 i[34]86-*-os9k
2460 IBM AIX PS/2 i[3456]86-*-aix
2461 Fujitsu FR30 fr30-*-elf*
2462 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2463 Argonaut Risc Chip (ARC) arc-*-*
2464 i386 running Mach 3.0 i[3456]86-*-mach3*
2465 i386 running Mach i[3456]86-*-mach*
2466 i386 running OSF/1 i[3456]86-*osf1mk*
2467 HP/Apollo 68k Family m68*-apollo*-sysv*,
2469 m68*-hp-bsd*, m68*-hp-hpux*
2470 I960 with MON960 i960-*-coff
2472 * OBSOLETE languages
2474 CHILL, a Pascal like language used by telecommunications companies.
2476 * REMOVED configurations and files
2478 AMD 29k family via UDI a29k-amd-udi, udi29k
2479 A29K VxWorks a29k-*-vxworks
2480 AMD 29000 embedded, using EBMON a29k-none-none
2481 AMD 29000 embedded with COFF a29k-none-coff
2482 AMD 29000 embedded with a.out a29k-none-aout
2484 testsuite/gdb.hp/gdb.threads-hp/ directory
2486 * New command "set max-user-call-depth <nnn>"
2488 This command allows the user to limit the call depth of user-defined
2489 commands. The default is 1024.
2491 * Changes in FreeBSD/i386 native debugging.
2493 Support for the "generate-core-file" has been added.
2495 * New commands "dump", "append", and "restore".
2497 These commands allow data to be copied from target memory
2498 to a bfd-format or binary file (dump and append), and back
2499 from a file into memory (restore).
2501 * Improved "next/step" support on multi-processor Alpha Tru64.
2503 The previous single-step mechanism could cause unpredictable problems,
2504 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2505 of a software single-step mechanism prevents this.
2507 *** Changes in GDB 5.2.1:
2515 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2516 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2517 Fix, by Joel Brobecker imported from mainline.
2519 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2520 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2521 Fix, by Fred Fish, imported from mainline.
2523 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2524 Surprisingly enough, it works now.
2525 By Michal Ludvig, imported from mainline.
2527 i386 hardware watchpoint support:
2528 avoid misses on second run for some targets.
2529 By Pierre Muller, imported from mainline.
2531 *** Changes in GDB 5.2:
2533 * New command "set trust-readonly-sections on[off]".
2535 This command is a hint that tells gdb that read-only sections
2536 really are read-only (ie. that their contents will not change).
2537 In this mode, gdb will go to the object file rather than the
2538 target to read memory from read-only sections (such as ".text").
2539 This can be a significant performance improvement on some
2540 (notably embedded) targets.
2542 * New command "generate-core-file" (or "gcore").
2544 This new gdb command allows the user to drop a core file of the child
2545 process state at any time. So far it's been implemented only for
2546 GNU/Linux and Solaris, but should be relatively easily ported to other
2547 hosts. Argument is core file name (defaults to core.<pid>).
2549 * New command line option
2551 GDB now accepts --pid or -p followed by a process id.
2553 * Change in command line behavior -- corefiles vs. process ids.
2555 There is a subtle behavior in the way in which GDB handles
2556 command line arguments. The first non-flag argument is always
2557 a program to debug, but the second non-flag argument may either
2558 be a corefile or a process id. Previously, GDB would attempt to
2559 open the second argument as a corefile, and if that failed, would
2560 issue a superfluous error message and then attempt to attach it as
2561 a process. Now, if the second argument begins with a non-digit,
2562 it will be treated as a corefile. If it begins with a digit,
2563 GDB will attempt to attach it as a process, and if no such process
2564 is found, will then attempt to open it as a corefile.
2566 * Changes in ARM configurations.
2568 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2569 configuration is fully multi-arch.
2571 * New native configurations
2573 ARM NetBSD arm*-*-netbsd*
2574 x86 OpenBSD i[3456]86-*-openbsd*
2575 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2576 Sparc64 running FreeBSD sparc64-*-freebsd*
2580 Sanyo XStormy16 xstormy16-elf
2582 * OBSOLETE configurations and files
2584 Configurations that have been declared obsolete in this release have
2585 been commented out. Unless there is activity to revive these
2586 configurations, the next release of GDB will have their sources
2587 permanently REMOVED.
2589 AMD 29k family via UDI a29k-amd-udi, udi29k
2590 A29K VxWorks a29k-*-vxworks
2591 AMD 29000 embedded, using EBMON a29k-none-none
2592 AMD 29000 embedded with COFF a29k-none-coff
2593 AMD 29000 embedded with a.out a29k-none-aout
2595 testsuite/gdb.hp/gdb.threads-hp/ directory
2597 * REMOVED configurations and files
2599 TI TMS320C80 tic80-*-*
2601 PowerPC Solaris powerpcle-*-solaris*
2602 PowerPC Windows NT powerpcle-*-cygwin32
2603 PowerPC Netware powerpc-*-netware*
2604 Harris/CXUX m88k m88*-harris-cxux*
2605 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2606 ns32k-utek-sysv* ns32k-utek-*
2607 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2608 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2609 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2610 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2611 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2613 * Changes to command line processing
2615 The new `--args' feature can be used to specify command-line arguments
2616 for the inferior from gdb's command line.
2618 * Changes to key bindings
2620 There is a new `operate-and-get-next' function bound to `C-o'.
2622 *** Changes in GDB 5.1.1
2624 Fix compile problem on DJGPP.
2626 Fix a problem with floating-point registers on the i386 being
2629 Fix to stop GDB crashing on .debug_str debug info.
2631 Numerous documentation fixes.
2633 Numerous testsuite fixes.
2635 *** Changes in GDB 5.1:
2637 * New native configurations
2639 Alpha FreeBSD alpha*-*-freebsd*
2640 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2641 MIPS GNU/Linux mips*-*-linux*
2642 MIPS SGI Irix 6.x mips*-sgi-irix6*
2643 ia64 AIX ia64-*-aix*
2644 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2648 Motorola 68HC11 and 68HC12 m68hc11-elf
2650 UltraSparc running GNU/Linux sparc64-*-linux*
2652 * OBSOLETE configurations and files
2654 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2655 Harris/CXUX m88k m88*-harris-cxux*
2656 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2657 ns32k-utek-sysv* ns32k-utek-*
2658 TI TMS320C80 tic80-*-*
2660 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2661 PowerPC Solaris powerpcle-*-solaris*
2662 PowerPC Windows NT powerpcle-*-cygwin32
2663 PowerPC Netware powerpc-*-netware*
2664 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2665 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2666 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2667 Apple Macintosh (MPW) host N/A
2669 stuff.c (Program to stuff files into a specially prepared space in kdb)
2670 kdb-start.c (Main loop for the standalone kernel debugger)
2672 Configurations that have been declared obsolete in this release have
2673 been commented out. Unless there is activity to revive these
2674 configurations, the next release of GDB will have their sources
2675 permanently REMOVED.
2677 * REMOVED configurations and files
2679 Altos 3068 m68*-altos-*
2680 Convex c1-*-*, c2-*-*
2682 ARM RISCix arm-*-* (as host)
2686 * GDB has been converted to ISO C.
2688 GDB's source code has been converted to ISO C. In particular, the
2689 sources are fully protoized, and rely on standard headers being
2694 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2696 * The MI enabled by default.
2698 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2699 revised and enabled by default. Packages which use GDB as a debugging
2700 engine behind a UI or another front end are encouraged to switch to
2701 using the GDB/MI interface, instead of the old annotations interface
2702 which is now deprecated.
2704 * Support for debugging Pascal programs.
2706 GDB now includes support for debugging Pascal programs. The following
2707 main features are supported:
2709 - Pascal-specific data types such as sets;
2711 - automatic recognition of Pascal sources based on file-name
2714 - Pascal-style display of data types, variables, and functions;
2716 - a Pascal expression parser.
2718 However, some important features are not yet supported.
2720 - Pascal string operations are not supported at all;
2722 - there are some problems with boolean types;
2724 - Pascal type hexadecimal constants are not supported
2725 because they conflict with the internal variables format;
2727 - support for Pascal objects and classes is not full yet;
2729 - unlike Pascal, GDB is case-sensitive for symbol names.
2731 * Changes in completion.
2733 Commands such as `shell', `run' and `set args', which pass arguments
2734 to inferior programs, now complete on file names, similar to what
2735 users expect at the shell prompt.
2737 Commands which accept locations, such as `disassemble', `print',
2738 `breakpoint', `until', etc. now complete on filenames as well as
2739 program symbols. Thus, if you type "break foob TAB", and the source
2740 files linked into the programs include `foobar.c', that file name will
2741 be one of the candidates for completion. However, file names are not
2742 considered for completion after you typed a colon that delimits a file
2743 name from a name of a function in that file, as in "break foo.c:bar".
2745 `set demangle-style' completes on available demangling styles.
2747 * New platform-independent commands:
2749 It is now possible to define a post-hook for a command as well as a
2750 hook that runs before the command. For more details, see the
2751 documentation of `hookpost' in the GDB manual.
2753 * Changes in GNU/Linux native debugging.
2755 Support for debugging multi-threaded programs has been completely
2756 revised for all platforms except m68k and sparc. You can now debug as
2757 many threads as your system allows you to have.
2759 Attach/detach is supported for multi-threaded programs.
2761 Support for SSE registers was added for x86. This doesn't work for
2762 multi-threaded programs though.
2764 * Changes in MIPS configurations.
2766 Multi-arch support is enabled for all MIPS configurations.
2768 GDB can now be built as native debugger on SGI Irix 6.x systems for
2769 debugging n32 executables. (Debugging 64-bit executables is not yet
2772 * Unified support for hardware watchpoints in all x86 configurations.
2774 Most (if not all) native x86 configurations support hardware-assisted
2775 breakpoints and watchpoints in a unified manner. This support
2776 implements debug register sharing between watchpoints, which allows to
2777 put a virtually infinite number of watchpoints on the same address,
2778 and also supports watching regions up to 16 bytes with several debug
2781 The new maintenance command `maintenance show-debug-regs' toggles
2782 debugging print-outs in functions that insert, remove, and test
2783 watchpoints and hardware breakpoints.
2785 * Changes in the DJGPP native configuration.
2787 New command ``info dos sysinfo'' displays assorted information about
2788 the CPU, OS, memory, and DPMI server.
2790 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2791 display information about segment descriptors stored in GDT, LDT, and
2794 New commands ``info dos pde'' and ``info dos pte'' display entries
2795 from Page Directory and Page Tables (for now works with CWSDPMI only).
2796 New command ``info dos address-pte'' displays the Page Table entry for
2797 a given linear address.
2799 GDB can now pass command lines longer than 126 characters to the
2800 program being debugged (requires an update to the libdbg.a library
2801 which is part of the DJGPP development kit).
2803 DWARF2 debug info is now supported.
2805 It is now possible to `step' and `next' through calls to `longjmp'.
2807 * Changes in documentation.
2809 All GDB documentation was converted to GFDL, the GNU Free
2810 Documentation License.
2812 Tracepoints-related commands are now fully documented in the GDB
2815 TUI, the Text-mode User Interface, is now documented in the manual.
2817 Tracepoints-related commands are now fully documented in the GDB
2820 The "GDB Internals" manual now has an index. It also includes
2821 documentation of `ui_out' functions, GDB coding standards, x86
2822 hardware watchpoints, and memory region attributes.
2824 * GDB's version number moved to ``version.in''
2826 The Makefile variable VERSION has been replaced by the file
2827 ``version.in''. People creating GDB distributions should update the
2828 contents of this file.
2832 GUD support is now a standard part of the EMACS distribution.
2834 *** Changes in GDB 5.0:
2836 * Improved support for debugging FP programs on x86 targets
2838 Unified and much-improved support for debugging floating-point
2839 programs on all x86 targets. In particular, ``info float'' now
2840 displays the FP registers in the same format on all x86 targets, with
2841 greater level of detail.
2843 * Improvements and bugfixes in hardware-assisted watchpoints
2845 It is now possible to watch array elements, struct members, and
2846 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2847 on x86 targets no longer erroneously trigger when the address is
2850 * Improvements in the native DJGPP version of GDB
2852 The distribution now includes all the scripts and auxiliary files
2853 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2854 machines ``out of the box''.
2856 The DJGPP version can now debug programs that use signals. It is
2857 possible to catch signals that happened in the debuggee, deliver
2858 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2859 would kill the program being debugged.) Programs that hook hardware
2860 interrupts (keyboard, timer, etc.) can also be debugged.
2862 It is now possible to debug DJGPP programs that redirect their
2863 standard handles or switch them to raw (as opposed to cooked) mode, or
2864 even close them. The command ``run < foo > bar'' works as expected,
2865 and ``info terminal'' reports useful information about the debuggee's
2866 terminal, including raw/cooked mode, redirection, etc.
2868 The DJGPP version now uses termios functions for console I/O, which
2869 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2872 DOS-style file names with drive letters are now fully supported by
2875 It is now possible to debug DJGPP programs that switch their working
2876 directory. It is also possible to rerun the debuggee any number of
2877 times without restarting GDB; thus, you can use the same setup,
2878 breakpoints, etc. for many debugging sessions.
2880 * New native configurations
2882 ARM GNU/Linux arm*-*-linux*
2883 PowerPC GNU/Linux powerpc-*-linux*
2887 Motorola MCore mcore-*-*
2888 x86 VxWorks i[3456]86-*-vxworks*
2889 PowerPC VxWorks powerpc-*-vxworks*
2890 TI TMS320C80 tic80-*-*
2892 * OBSOLETE configurations
2894 Altos 3068 m68*-altos-*
2895 Convex c1-*-*, c2-*-*
2897 ARM RISCix arm-*-* (as host)
2900 Configurations that have been declared obsolete will be commented out,
2901 but the code will be left in place. If there is no activity to revive
2902 these configurations before the next release of GDB, the sources will
2903 be permanently REMOVED.
2905 * Gould support removed
2907 Support for the Gould PowerNode and NP1 has been removed.
2909 * New features for SVR4
2911 On SVR4 native platforms (such as Solaris), if you attach to a process
2912 without first loading a symbol file, GDB will now attempt to locate and
2913 load symbols from the running process's executable file.
2915 * Many C++ enhancements
2917 C++ support has been greatly improved. Overload resolution now works properly
2918 in almost all cases. RTTI support is on the way.
2920 * Remote targets can connect to a sub-program
2922 A popen(3) style serial-device has been added. This device starts a
2923 sub-process (such as a stand-alone simulator) and then communicates
2924 with that. The sub-program to run is specified using the syntax
2925 ``|<program> <args>'' vis:
2927 (gdb) set remotedebug 1
2928 (gdb) target extended-remote |mn10300-elf-sim program-args
2930 * MIPS 64 remote protocol
2932 A long standing bug in the mips64 remote protocol where by GDB
2933 expected certain 32 bit registers (ex SR) to be transfered as 32
2934 instead of 64 bits has been fixed.
2936 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2937 added to provide backward compatibility with older versions of GDB.
2939 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2941 The command ``set remotebinarydownload'' command has been replaced by
2942 ``set remote X-packet''. Other commands in ``set remote'' family
2943 include ``set remote P-packet''.
2945 * Breakpoint commands accept ranges.
2947 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2948 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2949 ``tracepoint passcount'' also accepts a range of tracepoints.
2951 * ``apropos'' command added.
2953 The ``apropos'' command searches through command names and
2954 documentation strings, printing out matches, making it much easier to
2955 try to find a command that does what you are looking for.
2959 A new machine oriented interface (MI) has been added to GDB. This
2960 interface is designed for debug environments running GDB as a separate
2961 process. This is part of the long term libGDB project. See the
2962 "GDB/MI" chapter of the GDB manual for further information. It can be
2963 enabled by configuring with:
2965 .../configure --enable-gdbmi
2967 *** Changes in GDB-4.18:
2969 * New native configurations
2971 HP-UX 10.20 hppa*-*-hpux10.20
2972 HP-UX 11.x hppa*-*-hpux11.0*
2973 M68K GNU/Linux m68*-*-linux*
2977 Fujitsu FR30 fr30-*-elf*
2978 Intel StrongARM strongarm-*-*
2979 Mitsubishi D30V d30v-*-*
2981 * OBSOLETE configurations
2983 Gould PowerNode, NP1 np1-*-*, pn-*-*
2985 Configurations that have been declared obsolete will be commented out,
2986 but the code will be left in place. If there is no activity to revive
2987 these configurations before the next release of GDB, the sources will
2988 be permanently REMOVED.
2992 As a compatibility experiment, GDB's source files buildsym.h and
2993 buildsym.c have been converted to pure standard C, no longer
2994 containing any K&R compatibility code. We believe that all systems in
2995 use today either come with a standard C compiler, or have a GCC port
2996 available. If this is not true, please report the affected
2997 configuration to bug-gdb@gnu.org immediately. See the README file for
2998 information about getting a standard C compiler if you don't have one
3003 GDB now uses readline 2.2.
3005 * set extension-language
3007 You can now control the mapping between filename extensions and source
3008 languages by using the `set extension-language' command. For instance,
3009 you can ask GDB to treat .c files as C++ by saying
3010 set extension-language .c c++
3011 The command `info extensions' lists all of the recognized extensions
3012 and their associated languages.
3014 * Setting processor type for PowerPC and RS/6000
3016 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3017 you can use the `set processor' command to specify what variant of the
3018 PowerPC family you are debugging. The command
3022 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3023 following PowerPC and RS6000 variants:
3025 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3026 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3028 403GC IBM PowerPC 403GC
3029 505 Motorola PowerPC 505
3030 860 Motorola PowerPC 860 or 850
3031 601 Motorola PowerPC 601
3032 602 Motorola PowerPC 602
3033 603 Motorola/IBM PowerPC 603 or 603e
3034 604 Motorola PowerPC 604 or 604e
3035 750 Motorola/IBM PowerPC 750 or 750
3037 At the moment, this command just tells GDB what to name the
3038 special-purpose processor registers. Since almost all the affected
3039 registers are inaccessible to user-level programs, this command is
3040 only useful for remote debugging in its present form.
3044 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3045 more extensive support for HP-UX. Added features include shared
3046 library support, kernel threads and hardware watchpoints for 11.00,
3047 support for HP's ANSI C and C++ compilers, and a compatibility mode
3048 for xdb and dbx commands.
3052 HP's donation includes the new concept of catchpoints, which is a
3053 generalization of the old catch command. On HP-UX, it is now possible
3054 to catch exec, fork, and vfork, as well as library loading.
3056 This means that the existing catch command has changed; its first
3057 argument now specifies the type of catch to be set up. See the
3058 output of "help catch" for a list of catchpoint types.
3060 * Debugging across forks
3062 On HP-UX, you can choose which process to debug when a fork() happens
3067 HP has donated a curses-based terminal user interface (TUI). To get
3068 it, build with --enable-tui. Although this can be enabled for any
3069 configuration, at present it only works for native HP debugging.
3071 * GDB remote protocol additions
3073 A new protocol packet 'X' that writes binary data is now available.
3074 Default behavior is to try 'X', then drop back to 'M' if the stub
3075 fails to respond. The settable variable `remotebinarydownload'
3076 allows explicit control over the use of 'X'.
3078 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3079 full 64-bit address. The command
3081 set remoteaddresssize 32
3083 can be used to revert to the old behaviour. For existing remote stubs
3084 the change should not be noticed, as the additional address information
3087 In order to assist in debugging stubs, you may use the maintenance
3088 command `packet' to send any text string to the stub. For instance,
3090 maint packet heythere
3092 sends the packet "$heythere#<checksum>". Note that it is very easy to
3093 disrupt a debugging session by sending the wrong packet at the wrong
3096 The compare-sections command allows you to compare section data on the
3097 target to what is in the executable file without uploading or
3098 downloading, by comparing CRC checksums.
3100 * Tracing can collect general expressions
3102 You may now collect general expressions at tracepoints. This requires
3103 further additions to the target-side stub; see tracepoint.c and
3104 doc/agentexpr.texi for further details.
3106 * mask-address variable for Mips
3108 For Mips targets, you may control the zeroing of the upper 32 bits of
3109 a 64-bit address by entering `set mask-address on'. This is mainly
3110 of interest to users of embedded R4xxx and R5xxx processors.
3112 * Higher serial baud rates
3114 GDB's serial code now allows you to specify baud rates 57600, 115200,
3115 230400, and 460800 baud. (Note that your host system may not be able
3116 to achieve all of these rates.)
3120 The i960 configuration now includes an initial implementation of a
3121 builtin simulator, contributed by Jim Wilson.
3124 *** Changes in GDB-4.17:
3126 * New native configurations
3128 Alpha GNU/Linux alpha*-*-linux*
3129 Unixware 2.x i[3456]86-unixware2*
3130 Irix 6.x mips*-sgi-irix6*
3131 PowerPC GNU/Linux powerpc-*-linux*
3132 PowerPC Solaris powerpcle-*-solaris*
3133 Sparc GNU/Linux sparc-*-linux*
3134 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3138 Argonaut Risc Chip (ARC) arc-*-*
3139 Hitachi H8/300S h8300*-*-*
3140 Matsushita MN10200 w/simulator mn10200-*-*
3141 Matsushita MN10300 w/simulator mn10300-*-*
3142 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3143 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3144 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3145 Mitsubishi D10V w/simulator d10v-*-*
3146 Mitsubishi M32R/D w/simulator m32r-*-elf*
3147 Tsqware Sparclet sparclet-*-*
3148 NEC V850 w/simulator v850-*-*
3150 * New debugging protocols
3152 ARM with RDI protocol arm*-*-*
3153 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3154 DDB and LSI variants of PMON protocol mips*-*-*
3155 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3156 PowerPC with SDS protocol powerpc{,le}-*-eabi
3157 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3161 All configurations can now understand and use the DWARF 2 debugging
3162 format. The choice is automatic, if the symbol file contains DWARF 2
3167 GDB now includes basic Java language support. This support is
3168 only useful with Java compilers that produce native machine code.
3170 * solib-absolute-prefix and solib-search-path
3172 For SunOS and SVR4 shared libraries, you may now set the prefix for
3173 loading absolute shared library symbol files, and the search path for
3174 locating non-absolute shared library symbol files.
3176 * Live range splitting
3178 GDB can now effectively debug code for which GCC has performed live
3179 range splitting as part of its optimization. See gdb/doc/LRS for
3180 more details on the expected format of the stabs information.
3184 GDB's support for the GNU Hurd, including thread debugging, has been
3185 updated to work with current versions of the Hurd.
3189 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3190 instruction set. ARM GDB automatically detects when Thumb
3191 instructions are in use, and adjusts disassembly and backtracing
3196 GDB's MIPS target configurations now handle the MIP16 16-bit
3201 GDB now includes support for overlays; if an executable has been
3202 linked such that multiple sections are based at the same address, GDB
3203 will decide which section to use for symbolic info. You can choose to
3204 control the decision manually, using overlay commands, or implement
3205 additional target-side support and use "overlay load-target" to bring
3206 in the overlay mapping. Do "help overlay" for more detail.
3210 The command "info symbol <address>" displays information about
3211 the symbol at the specified address.
3215 The standard remote protocol now includes an extension that allows
3216 asynchronous collection and display of trace data. This requires
3217 extensive support in the target-side debugging stub. Tracing mode
3218 includes a new interaction mode in GDB and new commands: see the
3219 file tracepoint.c for more details.
3223 Configurations for embedded MIPS now include a simulator contributed
3224 by Cygnus Solutions. The simulator supports the instruction sets
3225 of most MIPS variants.
3229 Sparc configurations may now include the ERC32 simulator contributed
3230 by the European Space Agency. The simulator is not built into
3231 Sparc targets by default; configure with --enable-sim to include it.
3235 For target configurations that may include multiple variants of a
3236 basic architecture (such as MIPS and SH), you may now set the
3237 architecture explicitly. "set arch" sets, "info arch" lists
3238 the possible architectures.
3240 *** Changes in GDB-4.16:
3242 * New native configurations
3244 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3245 M68K NetBSD m68k-*-netbsd*
3246 PowerPC AIX 4.x powerpc-*-aix*
3247 PowerPC MacOS powerpc-*-macos*
3248 PowerPC Windows NT powerpcle-*-cygwin32
3249 RS/6000 AIX 4.x rs6000-*-aix4*
3253 ARM with RDP protocol arm-*-*
3254 I960 with MON960 i960-*-coff
3255 MIPS VxWorks mips*-*-vxworks*
3256 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3257 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3259 Matra Sparclet sparclet-*-*
3263 The powerpc-eabi configuration now includes the PSIM simulator,
3264 contributed by Andrew Cagney, with assistance from Mike Meissner.
3265 PSIM is a very elaborate model of the PowerPC, including not only
3266 basic instruction set execution, but also details of execution unit
3267 performance and I/O hardware. See sim/ppc/README for more details.
3271 GDB now works with Solaris 2.5.
3273 * Windows 95/NT native
3275 GDB will now work as a native debugger on Windows 95 and Windows NT.
3276 To build it from source, you must use the "gnu-win32" environment,
3277 which uses a DLL to emulate enough of Unix to run the GNU tools.
3278 Further information, binaries, and sources are available at
3279 ftp.cygnus.com, under pub/gnu-win32.
3281 * dont-repeat command
3283 If a user-defined command includes the command `dont-repeat', then the
3284 command will not be repeated if the user just types return. This is
3285 useful if the command is time-consuming to run, so that accidental
3286 extra keystrokes don't run the same command many times.
3288 * Send break instead of ^C
3290 The standard remote protocol now includes an option to send a break
3291 rather than a ^C to the target in order to interrupt it. By default,
3292 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3294 * Remote protocol timeout
3296 The standard remote protocol includes a new variable `remotetimeout'
3297 that allows you to set the number of seconds before GDB gives up trying
3298 to read from the target. The default value is 2.
3300 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3302 By default GDB will automatically keep track of objects as they are
3303 loaded and unloaded by the dynamic linker. By using the command `set
3304 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3305 when shared library events occur, thus allowing you to set breakpoints
3306 in shared libraries which are explicitly loaded by the inferior.
3308 Note this feature does not work on hpux8. On hpux9 you must link
3309 /usr/lib/end.o into your program. This feature should work
3310 automatically on hpux10.
3312 * Irix 5.x hardware watchpoint support
3314 Irix 5 configurations now support the use of hardware watchpoints.
3316 * Mips protocol "SYN garbage limit"
3318 When debugging a Mips target using the `target mips' protocol, you
3319 may set the number of characters that GDB will ignore by setting
3320 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3321 every character. The default value is 1050.
3323 * Recording and replaying remote debug sessions
3325 If you set `remotelogfile' to the name of a file, gdb will write to it
3326 a recording of a remote debug session. This recording may then be
3327 replayed back to gdb using "gdbreplay". See gdbserver/README for
3328 details. This is useful when you have a problem with GDB while doing
3329 remote debugging; you can make a recording of the session and send it
3330 to someone else, who can then recreate the problem.
3332 * Speedups for remote debugging
3334 GDB includes speedups for downloading and stepping MIPS systems using
3335 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3336 and more efficient S-record downloading.
3338 * Memory use reductions and statistics collection
3340 GDB now uses less memory and reports statistics about memory usage.
3341 Try the `maint print statistics' command, for example.
3343 *** Changes in GDB-4.15:
3345 * Psymtabs for XCOFF
3347 The symbol reader for AIX GDB now uses partial symbol tables. This
3348 can greatly improve startup time, especially for large executables.
3350 * Remote targets use caching
3352 Remote targets now use a data cache to speed up communication with the
3353 remote side. The data cache could lead to incorrect results because
3354 it doesn't know about volatile variables, thus making it impossible to
3355 debug targets which use memory mapped I/O devices. `set remotecache
3356 off' turns the the data cache off.
3358 * Remote targets may have threads
3360 The standard remote protocol now includes support for multiple threads
3361 in the target system, using new protocol commands 'H' and 'T'. See
3362 gdb/remote.c for details.
3366 If GDB is configured with `--enable-netrom', then it will include
3367 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3368 acts as though it is a bank of ROM on the target board, but you can
3369 write into it over the network. GDB's support consists only of
3370 support for fast loading into the emulated ROM; to debug, you must use
3371 another protocol, such as standard remote protocol. The usual
3372 sequence is something like
3374 target nrom <netrom-hostname>
3376 target remote <netrom-hostname>:1235
3380 GDB now includes support for the Apple Macintosh, as a host only. It
3381 may be run as either an MPW tool or as a standalone application, and
3382 it can debug through the serial port. All the usual GDB commands are
3383 available, but to the target command, you must supply "serial" as the
3384 device type instead of "/dev/ttyXX". See mpw-README in the main
3385 directory for more information on how to build. The MPW configuration
3386 scripts */mpw-config.in support only a few targets, and only the
3387 mips-idt-ecoff target has been tested.
3391 GDB configuration now uses autoconf. This is not user-visible,
3392 but does simplify configuration and building.
3396 GDB now supports hpux10.
3398 *** Changes in GDB-4.14:
3400 * New native configurations
3402 x86 FreeBSD i[345]86-*-freebsd
3403 x86 NetBSD i[345]86-*-netbsd
3404 NS32k NetBSD ns32k-*-netbsd
3405 Sparc NetBSD sparc-*-netbsd
3409 A29K VxWorks a29k-*-vxworks
3410 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3411 CPU32 EST-300 emulator m68*-*-est*
3412 PowerPC ELF powerpc-*-elf
3415 * Alpha OSF/1 support for procfs
3417 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3418 possible to attach to running processes. As the mounting of the /proc
3419 filesystem is optional on the Alpha, GDB automatically determines
3420 the availability of /proc during startup. This can lead to problems
3421 if /proc is unmounted after GDB has been started.
3423 * Arguments to user-defined commands
3425 User commands may accept up to 10 arguments separated by whitespace.
3426 Arguments are accessed within the user command via $arg0..$arg9. A
3429 print $arg0 + $arg1 + $arg2
3431 To execute the command use:
3434 Defines the command "adder" which prints the sum of its three arguments.
3435 Note the arguments are text substitutions, so they may reference variables,
3436 use complex expressions, or even perform inferior function calls.
3438 * New `if' and `while' commands
3440 This makes it possible to write more sophisticated user-defined
3441 commands. Both commands take a single argument, which is the
3442 expression to evaluate, and must be followed by the commands to
3443 execute, one per line, if the expression is nonzero, the list being
3444 terminated by the word `end'. The `if' command list may include an
3445 `else' word, which causes the following commands to be executed only
3446 if the expression is zero.
3448 * Fortran source language mode
3450 GDB now includes partial support for Fortran 77. It will recognize
3451 Fortran programs and can evaluate a subset of Fortran expressions, but
3452 variables and functions may not be handled correctly. GDB will work
3453 with G77, but does not yet know much about symbols emitted by other
3456 * Better HPUX support
3458 Most debugging facilities now work on dynamic executables for HPPAs
3459 running hpux9 or later. You can attach to running dynamically linked
3460 processes, but by default the dynamic libraries will be read-only, so
3461 for instance you won't be able to put breakpoints in them. To change
3462 that behavior do the following before running the program:
3468 This will cause the libraries to be mapped private and read-write.
3469 To revert to the normal behavior, do this:
3475 You cannot set breakpoints or examine data in the library until after
3476 the library is loaded if the function/data symbols do not have
3479 GDB can now also read debug symbols produced by the HP C compiler on
3480 HPPAs (sorry, no C++, Fortran or 68k support).
3482 * Target byte order now dynamically selectable
3484 You can choose which byte order to use with a target system, via the
3485 commands "set endian big" and "set endian little", and you can see the
3486 current setting by using "show endian". You can also give the command
3487 "set endian auto", in which case GDB will use the byte order
3488 associated with the executable. Currently, only embedded MIPS
3489 configurations support dynamic selection of target byte order.
3491 * New DOS host serial code
3493 This version uses DPMI interrupts to handle buffered I/O, so you
3494 no longer need to run asynctsr when debugging boards connected to
3497 *** Changes in GDB-4.13:
3499 * New "complete" command
3501 This lists all the possible completions for the rest of the line, if it
3502 were to be given as a command itself. This is intended for use by emacs.
3504 * Trailing space optional in prompt
3506 "set prompt" no longer adds a space for you after the prompt you set. This
3507 allows you to set a prompt which ends in a space or one that does not.
3509 * Breakpoint hit counts
3511 "info break" now displays a count of the number of times the breakpoint
3512 has been hit. This is especially useful in conjunction with "ignore"; you
3513 can ignore a large number of breakpoint hits, look at the breakpoint info
3514 to see how many times the breakpoint was hit, then run again, ignoring one
3515 less than that number, and this will get you quickly to the last hit of
3518 * Ability to stop printing at NULL character
3520 "set print null-stop" will cause GDB to stop printing the characters of
3521 an array when the first NULL is encountered. This is useful when large
3522 arrays actually contain only short strings.
3524 * Shared library breakpoints
3526 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3527 breakpoints in shared libraries before the executable is run.
3529 * Hardware watchpoints
3531 There is a new hardware breakpoint for the watch command for sparclite
3532 targets. See gdb/sparclite/hw_breakpoint.note.
3534 Hardware watchpoints are also now supported under GNU/Linux.
3538 Annotations have been added. These are for use with graphical interfaces,
3539 and are still experimental. Currently only gdba.el uses these.
3541 * Improved Irix 5 support
3543 GDB now works properly with Irix 5.2.
3545 * Improved HPPA support
3547 GDB now works properly with the latest GCC and GAS.
3549 * New native configurations
3551 Sequent PTX4 i[34]86-sequent-ptx4
3552 HPPA running OSF/1 hppa*-*-osf*
3553 Atari TT running SVR4 m68*-*-sysv4*
3554 RS/6000 LynxOS rs6000-*-lynxos*
3558 OS/9000 i[34]86-*-os9k
3559 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3562 * Hitachi SH7000 and E7000-PC ICE support
3564 There is now support for communicating with the Hitachi E7000-PC ICE.
3565 This is available automatically when GDB is configured for the SH.
3569 As usual, a variety of small fixes and improvements, both generic
3570 and configuration-specific. See the ChangeLog for more detail.
3572 *** Changes in GDB-4.12:
3574 * Irix 5 is now supported
3578 GDB-4.12 on the HPPA has a number of changes which make it unable
3579 to debug the output from the currently released versions of GCC and
3580 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3581 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3582 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3585 *** Changes in GDB-4.11:
3587 * User visible changes:
3591 The "set remotedebug" option is now consistent between the mips remote
3592 target, remote targets using the gdb-specific protocol, UDI (AMD's
3593 debug protocol for the 29k) and the 88k bug monitor. It is now an
3594 integer specifying a debug level (normally 0 or 1, but 2 means more
3595 debugging info for the mips target).
3597 * DEC Alpha native support
3599 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3600 debug info, but GDB works fairly well with the DEC compiler and should
3601 work with a future GCC release. See the README file for a few
3602 Alpha-specific notes.
3604 * Preliminary thread implementation
3606 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3608 * LynxOS native and target support for 386
3610 This release has been hosted on LynxOS 2.2, and also can be configured
3611 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3614 * Improvements in C++ mangling/demangling.
3616 This release has much better g++ debugging, specifically in name
3617 mangling/demangling, virtual function calls, print virtual table,
3618 call methods, ...etc.
3620 *** Changes in GDB-4.10:
3622 * User visible changes:
3624 Remote debugging using the GDB-specific (`target remote') protocol now
3625 supports the `load' command. This is only useful if you have some
3626 other way of getting the stub to the target system, and you can put it
3627 somewhere in memory where it won't get clobbered by the download.
3629 Filename completion now works.
3631 When run under emacs mode, the "info line" command now causes the
3632 arrow to point to the line specified. Also, "info line" prints
3633 addresses in symbolic form (as well as hex).
3635 All vxworks based targets now support a user settable option, called
3636 vxworks-timeout. This option represents the number of seconds gdb
3637 should wait for responses to rpc's. You might want to use this if
3638 your vxworks target is, perhaps, a slow software simulator or happens
3639 to be on the far side of a thin network line.
3643 This release contains support for using a DEC alpha as a GDB host for
3644 cross debugging. Native alpha debugging is not supported yet.
3647 *** Changes in GDB-4.9:
3651 This is the first GDB release which is accompanied by a matching testsuite.
3652 The testsuite requires installation of dejagnu, which should be available
3653 via ftp from most sites that carry GNU software.
3657 'Cfront' style demangling has had its name changed to 'ARM' style, to
3658 emphasize that it was written from the specifications in the C++ Annotated
3659 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3660 disclaimers, it still generated too much confusion with users attempting to
3661 use gdb with AT&T cfront.
3665 GDB now uses a standard remote interface to a simulator library.
3666 So far, the library contains simulators for the Zilog Z8001/2, the
3667 Hitachi H8/300, H8/500 and Super-H.
3669 * New targets supported
3671 H8/300 simulator h8300-hitachi-hms or h8300hms
3672 H8/500 simulator h8500-hitachi-hms or h8500hms
3673 SH simulator sh-hitachi-hms or sh
3674 Z8000 simulator z8k-zilog-none or z8ksim
3675 IDT MIPS board over serial line mips-idt-ecoff
3677 Cross-debugging to GO32 targets is supported. It requires a custom
3678 version of the i386-stub.c module which is integrated with the
3679 GO32 memory extender.
3681 * New remote protocols
3683 MIPS remote debugging protocol.
3685 * New source languages supported
3687 This version includes preliminary support for Chill, a Pascal like language
3688 used by telecommunications companies. Chill support is also being integrated
3689 into the GNU compiler, but we don't know when it will be publically available.
3692 *** Changes in GDB-4.8:
3694 * HP Precision Architecture supported
3696 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3697 version of this support was available as a set of patches from the
3698 University of Utah. GDB does not support debugging of programs
3699 compiled with the HP compiler, because HP will not document their file
3700 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3701 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3703 Many problems in the preliminary version have been fixed.
3705 * Faster and better demangling
3707 We have improved template demangling and fixed numerous bugs in the GNU style
3708 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3709 character types (wchar_t) are now supported. Demangling of each symbol is now
3710 only done once, and is cached when the symbol table for a file is read in.
3711 This results in a small increase in memory usage for C programs, a moderate
3712 increase in memory usage for C++ programs, and a fantastic speedup in
3715 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3716 from the specifications in the Annotated Reference Manual, which AT&T's
3717 compiler does not actually implement.
3719 * G++ multiple inheritance compiler problem
3721 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3722 inheritance lattices was reworked to properly discover ambiguities. We
3723 recently found an example which causes this new algorithm to fail in a
3724 very subtle way, producing bad debug information for those classes.
3725 The file 'gcc.patch' (in this directory) can be applied to gcc to
3726 circumvent the problem. A future GCC release will contain a complete
3729 The previous G++ debug info problem (mentioned below for the gdb-4.7
3730 release) is fixed in gcc version 2.3.2.
3732 * Improved configure script
3734 The `configure' script will now attempt to guess your system type if
3735 you don't supply a host system type. The old scheme of supplying a
3736 host system triplet is preferable over using this. All the magic is
3737 done in the new `config.guess' script. Examine it for details.
3739 We have also brought our configure script much more in line with the FSF's
3740 version. It now supports the --with-xxx options. In particular,
3741 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3742 The resulting GDB will not be able to read arbitrary object file formats --
3743 only the format ``expected'' to be used on the configured target system.
3744 We hope to make this the default in a future release.
3746 * Documentation improvements
3748 There's new internal documentation on how to modify GDB, and how to
3749 produce clean changes to the code. We implore people to read it
3750 before submitting changes.
3752 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3753 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3754 `info' files are also provided. To build `info' files from scratch,
3755 you will need the latest `makeinfo' release, which will be available in
3756 a future texinfo-X.Y release.
3758 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3759 We're not sure exactly which versions have this problem, but it has
3760 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3761 or better. If that isn't possible, there is a patch in
3762 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3763 around this problem.
3767 GDB now supports array constants that can be used in expressions typed in by
3768 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3769 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3772 The new directory `gdb/sparclite' contains a program that demonstrates
3773 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3775 * New native hosts supported
3777 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3778 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3780 * New targets supported
3782 AMD 29k family via UDI a29k-amd-udi or udi29k
3784 * New file formats supported
3786 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3787 HPUX core files, and SCO 3.2v2 core files.
3791 Attaching to processes now works again; thanks for the many bug reports.
3793 We have also stomped on a bunch of core dumps caused by
3794 printf_filtered("%s") problems.
3796 We eliminated a copyright problem on the rpc and ptrace header files
3797 for VxWorks, which was discovered at the last minute during the 4.7
3798 release. You should now be able to build a VxWorks GDB.
3800 You can now interrupt gdb while an attached process is running. This
3801 will cause the attached process to stop, and give control back to GDB.
3803 We fixed problems caused by using too many file descriptors
3804 for reading symbols from object files and libraries. This was
3805 especially a problem for programs that used many (~100) shared
3808 The `step' command now only enters a subroutine if there is line number
3809 information for the subroutine. Otherwise it acts like the `next'
3810 command. Previously, `step' would enter subroutines if there was
3811 any debugging information about the routine. This avoids problems
3812 when using `cc -g1' on MIPS machines.
3814 * Internal improvements
3816 GDB's internal interfaces have been improved to make it easier to support
3817 debugging of multiple languages in the future.
3819 GDB now uses a common structure for symbol information internally.
3820 Minimal symbols (derived from linkage symbols in object files), partial
3821 symbols (from a quick scan of debug information), and full symbols
3822 contain a common subset of information, making it easier to write
3823 shared code that handles any of them.
3825 * New command line options
3827 We now accept --silent as an alias for --quiet.
3831 The memory-mapped-malloc library is now licensed under the GNU Library
3832 General Public License.
3834 *** Changes in GDB-4.7:
3836 * Host/native/target split
3838 GDB has had some major internal surgery to untangle the support for
3839 hosts and remote targets. Now, when you configure GDB for a remote
3840 target, it will no longer load in all of the support for debugging
3841 local programs on the host. When fully completed and tested, this will
3842 ensure that arbitrary host/target combinations are possible.
3844 The primary conceptual shift is to separate the non-portable code in
3845 GDB into three categories. Host specific code is required any time GDB
3846 is compiled on that host, regardless of the target. Target specific
3847 code relates to the peculiarities of the target, but can be compiled on
3848 any host. Native specific code is everything else: it can only be
3849 built when the host and target are the same system. Child process
3850 handling and core file support are two common `native' examples.
3852 GDB's use of /proc for controlling Unix child processes is now cleaner.
3853 It has been split out into a single module under the `target_ops' vector,
3854 plus two native-dependent functions for each system that uses /proc.
3856 * New hosts supported
3858 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3859 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3860 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3862 * New targets supported
3864 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3865 68030 and CPU32 m68030-*-*, m68332-*-*
3867 * New native hosts supported
3869 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3870 (386bsd is not well tested yet)
3871 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3873 * New file formats supported
3875 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3876 supports reading of `a.out.adobe' object files, which are an a.out
3877 format extended with minimal information about multiple sections.
3881 `show copying' is the same as the old `info copying'.
3882 `show warranty' is the same as `info warrantee'.
3883 These were renamed for consistency. The old commands continue to work.
3885 `info handle' is a new alias for `info signals'.
3887 You can now define pre-command hooks, which attach arbitrary command
3888 scripts to any command. The commands in the hook will be executed
3889 prior to the user's command. You can also create a hook which will be
3890 executed whenever the program stops. See gdb.texinfo.
3894 We now deal with Cfront style name mangling, and can even extract type
3895 info from mangled symbols. GDB can automatically figure out which
3896 symbol mangling style your C++ compiler uses.
3898 Calling of methods and virtual functions has been improved as well.
3902 The crash that occured when debugging Sun Ansi-C compiled binaries is
3903 fixed. This was due to mishandling of the extra N_SO stabs output
3906 We also finally got Ultrix 4.2 running in house, and fixed core file
3907 support, with help from a dozen people on the net.
3909 John M. Farrell discovered that the reason that single-stepping was so
3910 slow on all of the Mips based platforms (primarily SGI and DEC) was
3911 that we were trying to demangle and lookup a symbol used for internal
3912 purposes on every instruction that was being stepped through. Changing
3913 the name of that symbol so that it couldn't be mistaken for a C++
3914 mangled symbol sped things up a great deal.
3916 Rich Pixley sped up symbol lookups in general by getting much smarter
3917 about when C++ symbol mangling is necessary. This should make symbol
3918 completion (TAB on the command line) much faster. It's not as fast as
3919 we'd like, but it's significantly faster than gdb-4.6.
3923 A new user controllable variable 'call_scratch_address' can
3924 specify the location of a scratch area to be used when GDB
3925 calls a function in the target. This is necessary because the
3926 usual method of putting the scratch area on the stack does not work
3927 in systems that have separate instruction and data spaces.
3929 We integrated changes to support the 29k UDI (Universal Debugger
3930 Interface), but discovered at the last minute that we didn't have all
3931 of the appropriate copyright paperwork. We are working with AMD to
3932 resolve this, and hope to have it available soon.
3936 We have sped up the remote serial line protocol, especially for targets
3937 with lots of registers. It now supports a new `expedited status' ('T')
3938 message which can be used in place of the existing 'S' status message.
3939 This allows the remote stub to send only the registers that GDB
3940 needs to make a quick decision about single-stepping or conditional
3941 breakpoints, eliminating the need to fetch the entire register set for
3942 each instruction being stepped through.
3944 The GDB remote serial protocol now implements a write-through cache for
3945 registers, only re-reading the registers if the target has run.
3947 There is also a new remote serial stub for SPARC processors. You can
3948 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3949 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3950 processor with a serial port.
3954 Configure.in files have become much easier to read and modify. A new
3955 `table driven' format makes it more obvious what configurations are
3956 supported, and what files each one uses.
3960 There is a new opcodes library which will eventually contain all of the
3961 disassembly routines and opcode tables. At present, it only contains
3962 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3963 disassembler (binutils/objdump) to share these routines.
3965 The libiberty library is now copylefted under the GNU Library General
3966 Public License. This allows more liberal use, and was done so libg++
3967 can use it. This makes no difference to GDB, since the Library License
3968 grants all the rights from the General Public License.
3972 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3973 reference to the stabs symbol info used by the debugger. It is (as far
3974 as we know) the only published document on this fascinating topic. We
3975 encourage you to read it, compare it to the stabs information on your
3976 system, and send improvements on the document in general (to
3977 bug-gdb@prep.ai.mit.edu).
3979 And, of course, many bugs have been fixed.
3982 *** Changes in GDB-4.6:
3984 * Better support for C++ function names
3986 GDB now accepts as input the "demangled form" of C++ overloaded function
3987 names and member function names, and can do command completion on such names
3988 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3989 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3990 Make use of command completion, it is your friend.
3992 GDB also now accepts a variety of C++ mangled symbol formats. They are
3993 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3994 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3995 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3996 for the list of formats.
3998 * G++ symbol mangling problem
4000 Recent versions of gcc have a bug in how they emit debugging information for
4001 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4002 directory) can be applied to gcc to fix the problem. Alternatively, if you
4003 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4004 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4005 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4008 * New 'maintenance' command
4010 All of the commands related to hacking GDB internals have been moved out of
4011 the main command set, and now live behind the 'maintenance' command. This
4012 can also be abbreviated as 'mt'. The following changes were made:
4014 dump-me -> maintenance dump-me
4015 info all-breakpoints -> maintenance info breakpoints
4016 printmsyms -> maintenance print msyms
4017 printobjfiles -> maintenance print objfiles
4018 printpsyms -> maintenance print psymbols
4019 printsyms -> maintenance print symbols
4021 The following commands are new:
4023 maintenance demangle Call internal GDB demangler routine to
4024 demangle a C++ link name and prints the result.
4025 maintenance print type Print a type chain for a given symbol
4027 * Change to .gdbinit file processing
4029 We now read the $HOME/.gdbinit file before processing the argv arguments
4030 (e.g. reading symbol files or core files). This allows global parameters to
4031 be set, which will apply during the symbol reading. The ./.gdbinit is still
4032 read after argv processing.
4034 * New hosts supported
4036 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4038 GNU/Linux support i386-unknown-linux or linux
4040 We are also including code to support the HP/PA running BSD and HPUX. This
4041 is almost guaranteed not to work, as we didn't have time to test or build it
4042 for this release. We are including it so that the more adventurous (or
4043 masochistic) of you can play with it. We also had major problems with the
4044 fact that the compiler that we got from HP doesn't support the -g option.
4047 * New targets supported
4049 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4051 * More smarts about finding #include files
4053 GDB now remembers the compilation directory for all include files, and for
4054 all files from which C is generated (like yacc and lex sources). This
4055 greatly improves GDB's ability to find yacc/lex sources, and include files,
4056 especially if you are debugging your program from a directory different from
4057 the one that contains your sources.
4059 We also fixed a bug which caused difficulty with listing and setting
4060 breakpoints in include files which contain C code. (In the past, you had to
4061 try twice in order to list an include file that you hadn't looked at before.)
4063 * Interesting infernals change
4065 GDB now deals with arbitrary numbers of sections, where the symbols for each
4066 section must be relocated relative to that section's landing place in the
4067 target's address space. This work was needed to support ELF with embedded
4068 stabs used by Solaris-2.0.
4070 * Bug fixes (of course!)
4072 There have been loads of fixes for the following things:
4073 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4074 i960, stabs, DOS(GO32), procfs, etc...
4076 See the ChangeLog for details.
4078 *** Changes in GDB-4.5:
4080 * New machines supported (host and target)
4082 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4084 SGI Irix-4.x mips-sgi-irix4 or iris4
4086 * New malloc package
4088 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4089 Mmalloc is capable of handling mutiple heaps of memory. It is also
4090 capable of saving a heap to a file, and then mapping it back in later.
4091 This can be used to greatly speedup the startup of GDB by using a
4092 pre-parsed symbol table which lives in a mmalloc managed heap. For
4093 more details, please read mmalloc/mmalloc.texi.
4097 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4098 'help info proc' for details.
4100 * MIPS ecoff symbol table format
4102 The code that reads MIPS symbol table format is now supported on all hosts.
4103 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4106 * File name changes for MS-DOS
4108 Many files in the config directories have been renamed to make it easier to
4109 support GDB on MS-DOSe systems (which have very restrictive file name
4110 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4111 environment) is close to working but has some remaining problems. Note
4112 that debugging of DOS programs is not supported, due to limitations
4113 in the ``operating system'', but it can be used to host cross-debugging.
4115 * Cross byte order fixes
4117 Many fixes have been made to support cross debugging of Sparc and MIPS
4118 targets from hosts whose byte order differs.
4120 * New -mapped and -readnow options
4122 If memory-mapped files are available on your system through the 'mmap'
4123 system call, you can use the -mapped option on the `file' or
4124 `symbol-file' commands to cause GDB to write the symbols from your
4125 program into a reusable file. If the program you are debugging is
4126 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4127 Future GDB debugging sessions will notice the presence of this file,
4128 and will quickly map in symbol information from it, rather than reading
4129 the symbol table from the executable program. Using the '-mapped'
4130 option in a GDB `file' or `symbol-file' command has the same effect as
4131 starting GDB with the '-mapped' command-line option.
4133 You can cause GDB to read the entire symbol table immediately by using
4134 the '-readnow' option with any of the commands that load symbol table
4135 information (or on the GDB command line). This makes the command
4136 slower, but makes future operations faster.
4138 The -mapped and -readnow options are typically combined in order to
4139 build a `fred.syms' file that contains complete symbol information.
4140 A simple GDB invocation to do nothing but build a `.syms' file for future
4143 gdb -batch -nx -mapped -readnow programname
4145 The `.syms' file is specific to the host machine on which GDB is run.
4146 It holds an exact image of GDB's internal symbol table. It cannot be
4147 shared across multiple host platforms.
4149 * longjmp() handling
4151 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4152 siglongjmp() without losing control. This feature has not yet been ported to
4153 all systems. It currently works on many 386 platforms, all MIPS-based
4154 platforms (SGI, DECstation, etc), and Sun3/4.
4158 Preliminary work has been put in to support the new Solaris OS from Sun. At
4159 this time, it can control and debug processes, but it is not capable of
4164 As always, many many bug fixes. The major areas were with g++, and mipsread.
4165 People using the MIPS-based platforms should experience fewer mysterious
4166 crashes and trashed symbol tables.
4168 *** Changes in GDB-4.4:
4170 * New machines supported (host and target)
4172 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4174 BSD Reno on Vax vax-dec-bsd
4175 Ultrix on Vax vax-dec-ultrix
4177 * New machines supported (target)
4179 AMD 29000 embedded, using EBMON a29k-none-none
4183 GDB continues to improve its handling of C++. `References' work better.
4184 The demangler has also been improved, and now deals with symbols mangled as
4185 per the Annotated C++ Reference Guide.
4187 GDB also now handles `stabs' symbol information embedded in MIPS
4188 `ecoff' symbol tables. Since the ecoff format was not easily
4189 extensible to handle new languages such as C++, this appeared to be a
4190 good way to put C++ debugging info into MIPS binaries. This option
4191 will be supported in the GNU C compiler, version 2, when it is
4194 * New features for SVR4
4196 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4197 shared libraries. Debugging dynamically linked programs should present
4198 only minor differences from debugging statically linked programs.
4200 The `info proc' command will print out information about any process
4201 on an SVR4 system (including the one you are debugging). At the moment,
4202 it prints the address mappings of the process.
4204 If you bring up GDB on another SVR4 system, please send mail to
4205 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4207 * Better dynamic linking support in SunOS
4209 Reading symbols from shared libraries which contain debugging symbols
4210 now works properly. However, there remain issues such as automatic
4211 skipping of `transfer vector' code during function calls, which
4212 make it harder to debug code in a shared library, than to debug the
4213 same code linked statically.
4217 GDB is now using the latest `getopt' routines from the FSF. This
4218 version accepts the -- prefix for options with long names. GDB will
4219 continue to accept the old forms (-option and +option) as well.
4220 Various single letter abbreviations for options have been explicity
4221 added to the option table so that they won't get overshadowed in the
4222 future by other options that begin with the same letter.
4226 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4227 Many assorted bugs have been handled. Many more remain to be handled.
4228 See the various ChangeLog files (primarily in gdb and bfd) for details.
4231 *** Changes in GDB-4.3:
4233 * New machines supported (host and target)
4235 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4236 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4237 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4239 * Almost SCO Unix support
4241 We had hoped to support:
4242 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4243 (except for core file support), but we discovered very late in the release
4244 that it has problems with process groups that render gdb unusable. Sorry
4245 about that. I encourage people to fix it and post the fixes.
4247 * Preliminary ELF and DWARF support
4249 GDB can read ELF object files on System V Release 4, and can handle
4250 debugging records for C, in DWARF format, in ELF files. This support
4251 is preliminary. If you bring up GDB on another SVR4 system, please
4252 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4257 GDB now uses the latest `readline' library. One user-visible change
4258 is that two tabs will list possible command completions, which previously
4259 required typing M-? (meta-question mark, or ESC ?).
4263 The `stepi' bug that many of you noticed has been squashed.
4264 Many bugs in C++ have been handled. Many more remain to be handled.
4265 See the various ChangeLog files (primarily in gdb and bfd) for details.
4267 * State of the MIPS world (in case you wondered):
4269 GDB can understand the symbol tables emitted by the compilers
4270 supplied by most vendors of MIPS-based machines, including DEC. These
4271 symbol tables are in a format that essentially nobody else uses.
4273 Some versions of gcc come with an assembler post-processor called
4274 mips-tfile. This program is required if you want to do source-level
4275 debugging of gcc-compiled programs. I believe FSF does not ship
4276 mips-tfile with gcc version 1, but it will eventually come with gcc
4279 Debugging of g++ output remains a problem. g++ version 1.xx does not
4280 really support it at all. (If you're lucky, you should be able to get
4281 line numbers and stack traces to work, but no parameters or local
4282 variables.) With some work it should be possible to improve the
4285 When gcc version 2 is released, you will have somewhat better luck.
4286 However, even then you will get confusing results for inheritance and
4289 We will eventually provide full debugging of g++ output on
4290 DECstations. This will probably involve some kind of stabs-in-ecoff
4291 encapulation, but the details have not been worked out yet.
4294 *** Changes in GDB-4.2:
4296 * Improved configuration
4298 Only one copy of `configure' exists now, and it is not self-modifying.
4299 Porting BFD is simpler.
4303 The `step' and `next' commands now only stop at the first instruction
4304 of a source line. This prevents the multiple stops that used to occur
4305 in switch statements, for-loops, etc. `Step' continues to stop if a
4306 function that has debugging information is called within the line.
4310 Lots of small bugs fixed. More remain.
4312 * New host supported (not target)
4314 Intel 386 PC clone running Mach i386-none-mach
4317 *** Changes in GDB-4.1:
4319 * Multiple source language support
4321 GDB now has internal scaffolding to handle several source languages.
4322 It determines the type of each source file from its filename extension,
4323 and will switch expression parsing and number formatting to match the
4324 language of the function in the currently selected stack frame.
4325 You can also specifically set the language to be used, with
4326 `set language c' or `set language modula-2'.
4330 GDB now has preliminary support for the GNU Modula-2 compiler,
4331 currently under development at the State University of New York at
4332 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4333 continue through the fall of 1991 and into 1992.
4335 Other Modula-2 compilers are currently not supported, and attempting to
4336 debug programs compiled with them will likely result in an error as the
4337 symbol table is read. Feel free to work on it, though!
4339 There are hooks in GDB for strict type checking and range checking,
4340 in the `Modula-2 philosophy', but they do not currently work.
4344 GDB can now write to executable and core files (e.g. patch
4345 a variable's value). You must turn this switch on, specify
4346 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4347 by assigning a new value to a variable. Modifications take
4350 * Automatic SunOS shared library reading
4352 When you run your program, GDB automatically determines where its
4353 shared libraries (if any) have been loaded, and reads their symbols.
4354 The `share' command is no longer needed. This also works when
4355 examining core files.
4359 You can specify the number of lines that the `list' command shows.
4362 * New machines supported (host and target)
4364 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4365 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4366 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4368 * New hosts supported (not targets)
4370 IBM RT/PC: romp-ibm-aix or rtpc
4372 * New targets supported (not hosts)
4374 AMD 29000 embedded with COFF a29k-none-coff
4375 AMD 29000 embedded with a.out a29k-none-aout
4376 Ultracomputer remote kernel debug a29k-nyu-kern
4378 * New remote interfaces
4384 *** Changes in GDB-4.0:
4388 Wide output is wrapped at good places to make the output more readable.
4390 Gdb now supports cross-debugging from a host machine of one type to a
4391 target machine of another type. Communication with the target system
4392 is over serial lines. The ``target'' command handles connecting to the
4393 remote system; the ``load'' command will download a program into the
4394 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4395 also supports debugging of realtime processes running under VxWorks,
4396 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4397 stub on the target system.
4399 New CPUs supported include the AMD 29000 and Intel 960.
4401 GDB now reads object files and symbol tables via a ``binary file''
4402 library, which allows a single copy of GDB to debug programs of multiple
4403 object file types such as a.out and coff.
4405 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4406 refcard.dvi and refcard.ps are available to format it).
4409 * Control-Variable user interface simplified
4411 All variables that control the operation of the debugger can be set
4412 by the ``set'' command, and displayed by the ``show'' command.
4414 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4415 ``Show prompt'' produces the response:
4416 Gdb's prompt is new-gdb=>.
4418 What follows are the NEW set commands. The command ``help set'' will
4419 print a complete list of old and new set commands. ``help set FOO''
4420 will give a longer description of the variable FOO. ``show'' will show
4421 all of the variable descriptions and their current settings.
4423 confirm on/off: Enables warning questions for operations that are
4424 hard to recover from, e.g. rerunning the program while
4425 it is already running. Default is ON.
4427 editing on/off: Enables EMACS style command line editing
4428 of input. Previous lines can be recalled with
4429 control-P, the current line can be edited with control-B,
4430 you can search for commands with control-R, etc.
4433 history filename NAME: NAME is where the gdb command history
4434 will be stored. The default is .gdb_history,
4435 or the value of the environment variable
4438 history size N: The size, in commands, of the command history. The
4439 default is 256, or the value of the environment variable
4442 history save on/off: If this value is set to ON, the history file will
4443 be saved after exiting gdb. If set to OFF, the
4444 file will not be saved. The default is OFF.
4446 history expansion on/off: If this value is set to ON, then csh-like
4447 history expansion will be performed on
4448 command line input. The default is OFF.
4450 radix N: Sets the default radix for input and output. It can be set
4451 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4452 in the current radix, so "set radix 10" is always a no-op.
4454 height N: This integer value is the number of lines on a page. Default
4455 is 24, the current `stty rows'' setting, or the ``li#''
4456 setting from the termcap entry matching the environment
4459 width N: This integer value is the number of characters on a line.
4460 Default is 80, the current `stty cols'' setting, or the ``co#''
4461 setting from the termcap entry matching the environment
4464 Note: ``set screensize'' is obsolete. Use ``set height'' and
4465 ``set width'' instead.
4467 print address on/off: Print memory addresses in various command displays,
4468 such as stack traces and structure values. Gdb looks
4469 more ``symbolic'' if you turn this off; it looks more
4470 ``machine level'' with it on. Default is ON.
4472 print array on/off: Prettyprint arrays. New convenient format! Default
4475 print demangle on/off: Print C++ symbols in "source" form if on,
4478 print asm-demangle on/off: Same, for assembler level printouts
4481 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4484 * Support for Epoch Environment.
4486 The epoch environment is a version of Emacs v18 with windowing. One
4487 new command, ``inspect'', is identical to ``print'', except that if you
4488 are running in the epoch environment, the value is printed in its own
4492 * Support for Shared Libraries
4494 GDB can now debug programs and core files that use SunOS shared libraries.
4495 Symbols from a shared library cannot be referenced
4496 before the shared library has been linked with the program (this
4497 happens after you type ``run'' and before the function main() is entered).
4498 At any time after this linking (including when examining core files
4499 from dynamically linked programs), gdb reads the symbols from each
4500 shared library when you type the ``sharedlibrary'' command.
4501 It can be abbreviated ``share''.
4503 sharedlibrary REGEXP: Load shared object library symbols for files
4504 matching a unix regular expression. No argument
4505 indicates to load symbols for all shared libraries.
4507 info sharedlibrary: Status of loaded shared libraries.
4512 A watchpoint stops execution of a program whenever the value of an
4513 expression changes. Checking for this slows down execution
4514 tremendously whenever you are in the scope of the expression, but is
4515 quite useful for catching tough ``bit-spreader'' or pointer misuse
4516 problems. Some machines such as the 386 have hardware for doing this
4517 more quickly, and future versions of gdb will use this hardware.
4519 watch EXP: Set a watchpoint (breakpoint) for an expression.
4521 info watchpoints: Information about your watchpoints.
4523 delete N: Deletes watchpoint number N (same as breakpoints).
4524 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4525 enable N: Re-enables watchpoint number N (same as breakpoints).
4528 * C++ multiple inheritance
4530 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4533 * C++ exception handling
4535 Gdb now supports limited C++ exception handling. Besides the existing
4536 ability to breakpoint on an exception handler, gdb can breakpoint on
4537 the raising of an exception (before the stack is peeled back to the
4540 catch FOO: If there is a FOO exception handler in the dynamic scope,
4541 set a breakpoint to catch exceptions which may be raised there.
4542 Multiple exceptions (``catch foo bar baz'') may be caught.
4544 info catch: Lists all exceptions which may be caught in the
4545 current stack frame.
4548 * Minor command changes
4550 The command ``call func (arg, arg, ...)'' now acts like the print
4551 command, except it does not print or save a value if the function's result
4552 is void. This is similar to dbx usage.
4554 The ``up'' and ``down'' commands now always print the frame they end up
4555 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4556 frames without printing.
4558 * New directory command
4560 'dir' now adds directories to the FRONT of the source search path.
4561 The path starts off empty. Source files that contain debug information
4562 about the directory in which they were compiled can be found even
4563 with an empty path; Sun CC and GCC include this information. If GDB can't
4564 find your source file in the current directory, type "dir .".
4566 * Configuring GDB for compilation
4568 For normal use, type ``./configure host''. See README or gdb.texinfo
4571 GDB now handles cross debugging. If you are remotely debugging between
4572 two different machines, type ``./configure host -target=targ''.
4573 Host is the machine where GDB will run; targ is the machine
4574 where the program that you are debugging will run.