1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.3
6 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
7 and "show remote hardware-watchpoint-length-limit". These allows to
8 set or show the maximum length limit (in bytes) of a remote
9 target hardware watchpoint.
11 This allows e.g. to use "unlimited" hardware watchpoints with the
12 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
13 watchpoints are slower than real hardware watchpoints but are
14 significantly faster than gdb software watchpoints.
18 ** The "maint set python print-stack on|off" command has been
19 deprecated, and a new command: "set python print-stack on|off" has
20 replaced it. Additionally, the default for "print-stack" is now
23 ** A prompt subsitution hook (prompt_hook) is now available to the
26 ** Python commands and convenience-functions located in
27 'data-directory'/python/gdb/command and
28 'data-directory'/python/gdb/function are now automatically loaded
31 ** Symbols now provide the "type" attribute, the type of the symbol.
33 * libthread-db-search-path now supports two special values: $sdir and $pdir.
34 $sdir specifies the default system locations of shared libraries.
35 $pdir specifies the directory where the libpthread used by the application
38 GDB no longer looks in $sdir and $pdir after it has searched the directories
39 mentioned in libthread-db-search-path. If you want to search those
40 directories, they must be specified in libthread-db-search-path.
41 The default value of libthread-db-search-path on GNU/Linux and Solaris
42 systems is now "$sdir:$pdir".
44 $pdir is not supported by gdbserver, it is currently ignored.
45 $sdir is supported by gdbserver.
47 * New configure option --with-iconv-bin.
48 When using the internationalization support like the one in the GNU C
49 library, GDB will invoke the "iconv" program to get a list of supported
50 character sets. If this program lives in a non-standard location, one can
51 use this option to specify where to find it.
53 * When natively debugging programs on PowerPC BookE processors running
54 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
55 watchpoints, which specify a mask in addition to an address to watch.
56 The mask specifies that some bits of an address (the bits which are
57 reset in the mask) should be ignored when matching the address accessed
58 by the inferior against the watchpoint address. See the "PowerPC Embedded"
59 section in the user manual for more details.
61 * The new option --once causes GDBserver to stop listening for connections once
62 the first connection is made. The listening port used by GDBserver will
63 become available after that.
65 * New commands "info macros", and "info definitions" have been added.
69 watch EXPRESSION mask MASK_VALUE
70 The watch command now supports the mask argument which allows creation
71 of masked watchpoints, if the current architecture supports this feature.
73 info auto-load-scripts [REGEXP]
74 This command was formerly named "maintenance print section-scripts".
75 It is now generally useful and is no longer a maintenance-only command.
77 * Tracepoints can now be enabled and disabled at any time after a trace
78 experiment has been started using the standard "enable" and "disable"
79 commands. It is now possible to start a trace experiment with no enabled
80 tracepoints; GDB will display a warning, but will allow the experiment to
81 begin, assuming that tracepoints will be enabled as needed while the trace
88 Dynamically enable a tracepoint in a started trace experiment.
92 Dynamically disable a tracepoint in a started trace experiment.
94 * Dcache size (number of lines) and line-size are now runtime-configurable
95 via "set dcache line" and "set dcache line-size" commands.
99 Texas Instruments TMS320C6x tic6x-*-*
101 *** Changes in GDB 7.3
103 * GDB has a new command: "thread find [REGEXP]".
104 It finds the thread id whose name, target id, or thread extra info
105 matches the given regular expression.
107 * The "catch syscall" command now works on mips*-linux* targets.
109 * The -data-disassemble MI command now supports modes 2 and 3 for
110 dumping the instruction opcodes.
112 * New command line options
114 -data-directory DIR Specify DIR as the "data-directory".
115 This is mostly for testing purposes.
117 * The "maint set python auto-load on|off" command has been renamed to
118 "set auto-load-scripts on|off".
120 * GDB has a new command: "set directories".
121 It is like the "dir" command except that it replaces the
122 source path list instead of augmenting it.
124 * GDB now understands thread names.
126 On GNU/Linux, "info threads" will display the thread name as set by
127 prctl or pthread_setname_np.
129 There is also a new command, "thread name", which can be used to
130 assign a name internally for GDB to display.
133 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
134 has been integrated into GDB.
138 ** The function gdb.Write now accepts an optional keyword 'stream'.
139 This keyword, when provided, will direct the output to either
140 stdout, stderr, or GDB's logging output.
142 ** Parameters can now be be sub-classed in Python, and in particular
143 you may implement the get_set_doc and get_show_doc functions.
144 This improves how Parameter set/show documentation is processed
145 and allows for more dynamic content.
147 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
148 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
149 have an is_valid method.
151 ** Breakpoints can now be sub-classed in Python, and in particular
152 you may implement a 'stop' function that is executed each time
153 the inferior reaches that breakpoint.
155 ** New function gdb.lookup_global_symbol looks up a global symbol.
157 ** GDB values in Python are now callable if the value represents a
158 function. For example, if 'some_value' represents a function that
159 takes two integer parameters and returns a value, you can call
160 that function like so:
162 result = some_value (10,20)
164 ** Module gdb.types has been added.
165 It contains a collection of utilities for working with gdb.Types objects:
166 get_basic_type, has_field, make_enum_dict.
168 ** Module gdb.printing has been added.
169 It contains utilities for writing and registering pretty-printers.
170 New classes: PrettyPrinter, SubPrettyPrinter,
171 RegexpCollectionPrettyPrinter.
172 New function: register_pretty_printer.
174 ** New commands "info pretty-printers", "enable pretty-printer" and
175 "disable pretty-printer" have been added.
177 ** gdb.parameter("directories") is now available.
179 ** New function gdb.newest_frame returns the newest frame in the
182 ** The gdb.InferiorThread class has a new "name" attribute. This
183 holds the thread's name.
185 ** Python Support for Inferior events.
186 Python scripts can add observers to be notified of events
187 occurring in the process being debugged.
188 The following events are currently supported:
189 - gdb.events.cont Continue event.
190 - gdb.events.exited Inferior exited event.
191 - gdb.events.stop Signal received, and Breakpoint hit events.
195 ** GDB now puts template parameters in scope when debugging in an
196 instantiation. For example, if you have:
198 template<int X> int func (void) { return X; }
200 then if you step into func<5>, "print X" will show "5". This
201 feature requires proper debuginfo support from the compiler; it
202 was added to GCC 4.5.
204 ** The motion commands "next", "finish", "until", and "advance" now
205 work better when exceptions are thrown. In particular, GDB will
206 no longer lose control of the inferior; instead, the GDB will
207 stop the inferior at the point at which the exception is caught.
208 This functionality requires a change in the exception handling
209 code that was introduced in GCC 4.5.
211 * GDB now follows GCC's rules on accessing volatile objects when
212 reading or writing target state during expression evaluation.
213 One notable difference to prior behavior is that "print x = 0"
214 no longer generates a read of x; the value of the assignment is
215 now always taken directly from the value being assigned.
217 * GDB now has some support for using labels in the program's source in
218 linespecs. For instance, you can use "advance label" to continue
219 execution to a label.
221 * GDB now has support for reading and writing a new .gdb_index
222 section. This section holds a fast index of DWARF debugging
223 information and can be used to greatly speed up GDB startup and
224 operation. See the documentation for `save gdb-index' for details.
226 * The "watch" command now accepts an optional "-location" argument.
227 When used, this causes GDB to watch the memory referred to by the
228 expression. Such a watchpoint is never deleted due to it going out
231 * GDB now supports thread debugging of core dumps on GNU/Linux.
233 GDB now activates thread debugging using the libthread_db library
234 when debugging GNU/Linux core dumps, similarly to when debugging
235 live processes. As a result, when debugging a core dump file, GDB
236 is now able to display pthread_t ids of threads. For example, "info
237 threads" shows the same output as when debugging the process when it
238 was live. In earlier releases, you'd see something like this:
241 * 1 LWP 6780 main () at main.c:10
243 While now you see this:
246 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
248 It is also now possible to inspect TLS variables when debugging core
251 When debugging a core dump generated on a machine other than the one
252 used to run GDB, you may need to point GDB at the correct
253 libthread_db library with the "set libthread-db-search-path"
254 command. See the user manual for more details on this command.
256 * When natively debugging programs on PowerPC BookE processors running
257 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
258 which stop execution of the inferior whenever it executes an instruction
259 at any address within the specified range. See the "PowerPC Embedded"
260 section in the user manual for more details.
262 * New features in the GDB remote stub, GDBserver
264 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
265 and i686 LynxOS (version 5.x).
267 ** GDBserver is now supported on Blackfin Linux.
269 * New native configurations
271 ia64 HP-UX ia64-*-hpux*
275 Analog Devices, Inc. Blackfin Processor bfin-*
277 * Ada task switching is now supported on sparc-elf targets when
278 debugging a program using the Ravenscar Profile. For more information,
279 see the "Tasking Support when using the Ravenscar Profile" section
280 in the GDB user manual.
282 * Guile support was removed.
284 * New features in the GNU simulator
286 ** The --map-info flag lists all known core mappings.
288 ** CFI flashes may be simulated via the "cfi" device.
290 *** Changes in GDB 7.2
292 * Shared library support for remote targets by default
294 When GDB is configured for a generic, non-OS specific target, like
295 for example, --target=arm-eabi or one of the many *-*-elf targets,
296 GDB now queries remote stubs for loaded shared libraries using the
297 `qXfer:libraries:read' packet. Previously, shared library support
298 was always disabled for such configurations.
302 ** Argument Dependent Lookup (ADL)
304 In C++ ADL lookup directs function search to the namespaces of its
305 arguments even if the namespace has not been imported.
315 Here the compiler will search for `foo' in the namespace of 'b'
316 and find A::foo. GDB now supports this. This construct is commonly
317 used in the Standard Template Library for operators.
319 ** Improved User Defined Operator Support
321 In addition to member operators, GDB now supports lookup of operators
322 defined in a namespace and imported with a `using' directive, operators
323 defined in the global scope, operators imported implicitly from an
324 anonymous namespace, and the ADL operators mentioned in the previous
326 GDB now also supports proper overload resolution for all the previously
327 mentioned flavors of operators.
329 ** static const class members
331 Printing of static const class members that are initialized in the
332 class definition has been fixed.
334 * Windows Thread Information Block access.
336 On Windows targets, GDB now supports displaying the Windows Thread
337 Information Block (TIB) structure. This structure is visible either
338 by using the new command `info w32 thread-information-block' or, by
339 dereferencing the new convenience variable named `$_tlb', a
340 thread-specific pointer to the TIB. This feature is also supported
341 when remote debugging using GDBserver.
345 Static tracepoints are calls in the user program into a tracing
346 library. One such library is a port of the LTTng kernel tracer to
347 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
348 When debugging with GDBserver, GDB now supports combining the GDB
349 tracepoint machinery with such libraries. For example: the user can
350 use GDB to probe a static tracepoint marker (a call from the user
351 program into the tracing library) with the new "strace" command (see
352 "New commands" below). This creates a "static tracepoint" in the
353 breakpoint list, that can be manipulated with the same feature set
354 as fast and regular tracepoints. E.g., collect registers, local and
355 global variables, collect trace state variables, and define
356 tracepoint conditions. In addition, the user can collect extra
357 static tracepoint marker specific data, by collecting the new
358 $_sdata internal variable. When analyzing the trace buffer, you can
359 inspect $_sdata like any other variable available to GDB. For more
360 information, see the "Tracepoints" chapter in GDB user manual. New
361 remote packets have been defined to support static tracepoints, see
362 the "New remote packets" section below.
364 * Better reconstruction of tracepoints after disconnected tracing
366 GDB will attempt to download the original source form of tracepoint
367 definitions when starting a trace run, and then will upload these
368 upon reconnection to the target, resulting in a more accurate
369 reconstruction of the tracepoints that are in use on the target.
373 You can now exercise direct control over the ways that GDB can
374 affect your program. For instance, you can disallow the setting of
375 breakpoints, so that the program can run continuously (assuming
376 non-stop mode). In addition, the "observer" variable is available
377 to switch all of the different controls; in observer mode, GDB
378 cannot affect the target's behavior at all, which is useful for
379 tasks like diagnosing live systems in the field.
381 * The new convenience variable $_thread holds the number of the
388 Return the address of the Windows Thread Information Block of a given thread.
392 In response to several of the tracepoint packets, the target may now
393 also respond with a number of intermediate `qRelocInsn' request
394 packets before the final result packet, to have GDB handle
395 relocating an instruction to execute at a different address. This
396 is particularly useful for stubs that support fast tracepoints. GDB
397 reports support for this feature in the qSupported packet.
401 List static tracepoint markers in the target program.
405 List static tracepoint markers at a given address in the target
408 qXfer:statictrace:read
410 Read the static trace data collected (by a `collect $_sdata'
411 tracepoint action). The remote stub reports support for this packet
412 to gdb's qSupported query.
416 Send the current settings of GDB's permission flags.
420 Send part of the source (textual) form of a tracepoint definition,
421 which includes location, conditional, and action list.
423 * The source command now accepts a -s option to force searching for the
424 script in the source search path even if the script name specifies
427 * New features in the GDB remote stub, GDBserver
429 - GDBserver now support tracepoints (including fast tracepoints, and
430 static tracepoints). The feature is currently supported by the
431 i386-linux and amd64-linux builds. See the "Tracepoints support
432 in gdbserver" section in the manual for more information.
434 GDBserver JIT compiles the tracepoint's conditional agent
435 expression bytecode into native code whenever possible for low
436 overhead dynamic tracepoints conditionals. For such tracepoints,
437 an expression that examines program state is evaluated when the
438 tracepoint is reached, in order to determine whether to capture
439 trace data. If the condition is simple and false, processing the
440 tracepoint finishes very quickly and no data is gathered.
442 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
443 for static tracepoints support.
445 - GDBserver now supports x86_64 Windows 64-bit debugging.
447 * GDB now sends xmlRegisters= in qSupported packet to indicate that
448 it understands register description.
450 * The --batch flag now disables pagination and queries.
452 * X86 general purpose registers
454 GDB now supports reading/writing byte, word and double-word x86
455 general purpose registers directly. This means you can use, say,
456 $ah or $ax to refer, respectively, to the byte register AH and
457 16-bit word register AX that are actually portions of the 32-bit
458 register EAX or 64-bit register RAX.
460 * The `commands' command now accepts a range of breakpoints to modify.
461 A plain `commands' following a command that creates multiple
462 breakpoints affects all the breakpoints set by that command. This
463 applies to breakpoints set by `rbreak', and also applies when a
464 single `break' command creates multiple breakpoints (e.g.,
465 breakpoints on overloaded c++ functions).
467 * The `rbreak' command now accepts a filename specification as part of
468 its argument, limiting the functions selected by the regex to those
469 in the specified file.
471 * Support for remote debugging Windows and SymbianOS shared libraries
472 from Unix hosts has been improved. Non Windows GDB builds now can
473 understand target reported file names that follow MS-DOS based file
474 system semantics, such as file names that include drive letters and
475 use the backslash character as directory separator. This makes it
476 possible to transparently use the "set sysroot" and "set
477 solib-search-path" on Unix hosts to point as host copies of the
478 target's shared libraries. See the new command "set
479 target-file-system-kind" described below, and the "Commands to
480 specify files" section in the user manual for more information.
484 eval template, expressions...
485 Convert the values of one or more expressions under the control
486 of the string template to a command line, and call it.
488 set target-file-system-kind unix|dos-based|auto
489 show target-file-system-kind
490 Set or show the assumed file system kind for target reported file
493 save breakpoints <filename>
494 Save all current breakpoint definitions to a file suitable for use
495 in a later debugging session. To read the saved breakpoint
496 definitions, use the `source' command.
498 `save tracepoints' is a new alias for `save-tracepoints'. The latter
501 info static-tracepoint-markers
502 Display information about static tracepoint markers in the target.
504 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
505 Define a static tracepoint by probing a marker at the given
506 function, line, address, or marker ID.
510 Enable and disable observer mode.
512 set may-write-registers on|off
513 set may-write-memory on|off
514 set may-insert-breakpoints on|off
515 set may-insert-tracepoints on|off
516 set may-insert-fast-tracepoints on|off
517 set may-interrupt on|off
518 Set individual permissions for GDB effects on the target. Note that
519 some of these settings can have undesirable or surprising
520 consequences, particularly when changed in the middle of a session.
521 For instance, disabling the writing of memory can prevent
522 breakpoints from being inserted, cause single-stepping to fail, or
523 even crash your program, if you disable after breakpoints have been
524 inserted. However, GDB should not crash.
526 set record memory-query on|off
527 show record memory-query
528 Control whether to stop the inferior if memory changes caused
529 by an instruction cannot be recorded.
534 The disassemble command now supports "start,+length" form of two arguments.
538 ** GDB now provides a new directory location, called the python directory,
539 where Python scripts written for GDB can be installed. The location
540 of that directory is <data-directory>/python, where <data-directory>
541 is the GDB data directory. For more details, see section `Scripting
542 GDB using Python' in the manual.
544 ** The GDB Python API now has access to breakpoints, symbols, symbol
545 tables, program spaces, inferiors, threads and frame's code blocks.
546 Additionally, GDB Parameters can now be created from the API, and
547 manipulated via set/show in the CLI.
549 ** New functions gdb.target_charset, gdb.target_wide_charset,
550 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
552 ** New exception gdb.GdbError.
554 ** Pretty-printers are now also looked up in the current program space.
556 ** Pretty-printers can now be individually enabled and disabled.
558 ** GDB now looks for names of Python scripts to auto-load in a
559 special section named `.debug_gdb_scripts', in addition to looking
560 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
562 * Tracepoint actions were unified with breakpoint commands. In particular,
563 there are no longer differences in "info break" output for breakpoints and
564 tracepoints and the "commands" command can be used for both tracepoints and
569 ARM Symbian arm*-*-symbianelf*
571 * D language support.
572 GDB now supports debugging programs written in the D programming
575 * GDB now supports the extended ptrace interface for PowerPC which is
576 available since Linux kernel version 2.6.34. This automatically enables
577 any hardware breakpoints and additional hardware watchpoints available in
578 the processor. The old ptrace interface exposes just one hardware
579 watchpoint and no hardware breakpoints.
581 * GDB is now able to use the Data Value Compare (DVC) register available on
582 embedded PowerPC processors to implement in hardware simple watchpoint
583 conditions of the form:
585 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
587 This works in native GDB running on Linux kernels with the extended ptrace
588 interface mentioned above.
590 *** Changes in GDB 7.1
596 GDB now supports importing of namespaces in C++. This enables the
597 user to inspect variables from imported namespaces. Support for
598 namepace aliasing has also been added. So, if a namespace is
599 aliased in the current scope (e.g. namepace C=A; ) the user can
600 print variables using the alias (e.g. (gdb) print C::x).
604 All known bugs relating to the printing of virtual base class were
605 fixed. It is now possible to call overloaded static methods using a
610 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
611 and reinterpret_cast<> are now handled by the C++ expression parser.
615 Xilinx MicroBlaze microblaze-*-*
620 Xilinx MicroBlaze microblaze
623 * Multi-program debugging.
625 GDB now has support for multi-program (a.k.a. multi-executable or
626 multi-exec) debugging. This allows for debugging multiple inferiors
627 simultaneously each running a different program under the same GDB
628 session. See "Debugging Multiple Inferiors and Programs" in the
629 manual for more information. This implied some user visible changes
630 in the multi-inferior support. For example, "info inferiors" now
631 lists inferiors that are not running yet or that have exited
632 already. See also "New commands" and "New options" below.
634 * New tracing features
636 GDB's tracepoint facility now includes several new features:
638 ** Trace state variables
640 GDB tracepoints now include support for trace state variables, which
641 are variables managed by the target agent during a tracing
642 experiment. They are useful for tracepoints that trigger each
643 other, so for instance one tracepoint can count hits in a variable,
644 and then a second tracepoint has a condition that is true when the
645 count reaches a particular value. Trace state variables share the
646 $-syntax of GDB convenience variables, and can appear in both
647 tracepoint actions and condition expressions. Use the "tvariable"
648 command to create, and "info tvariables" to view; see "Trace State
649 Variables" in the manual for more detail.
653 GDB now includes an option for defining fast tracepoints, which
654 targets may implement more efficiently, such as by installing a jump
655 into the target agent rather than a trap instruction. The resulting
656 speedup can be by two orders of magnitude or more, although the
657 tradeoff is that some program locations on some target architectures
658 might not allow fast tracepoint installation, for instance if the
659 instruction to be replaced is shorter than the jump. To request a
660 fast tracepoint, use the "ftrace" command, with syntax identical to
661 the regular trace command.
663 ** Disconnected tracing
665 It is now possible to detach GDB from the target while it is running
666 a trace experiment, then reconnect later to see how the experiment
667 is going. In addition, a new variable disconnected-tracing lets you
668 tell the target agent whether to continue running a trace if the
669 connection is lost unexpectedly.
673 GDB now has the ability to save the trace buffer into a file, and
674 then use that file as a target, similarly to you can do with
675 corefiles. You can select trace frames, print data that was
676 collected in them, and use tstatus to display the state of the
677 tracing run at the moment that it was saved. To create a trace
678 file, use "tsave <filename>", and to use it, do "target tfile
681 ** Circular trace buffer
683 You can ask the target agent to handle the trace buffer as a
684 circular buffer, discarding the oldest trace frames to make room for
685 newer ones, by setting circular-trace-buffer to on. This feature may
686 not be available for all target agents.
691 The disassemble command, when invoked with two arguments, now requires
692 the arguments to be comma-separated.
695 The info variables command now displays variable definitions. Files
696 which only declare a variable are not shown.
699 The source command is now capable of sourcing Python scripts.
700 This feature is dependent on the debugger being build with Python
703 Related to this enhancement is also the introduction of a new command
704 "set script-extension" (see below).
706 * New commands (for set/show, see "New options" below)
708 record save [<FILENAME>]
709 Save a file (in core file format) containing the process record
710 execution log for replay debugging at a later time.
712 record restore <FILENAME>
713 Restore the process record execution log that was saved at an
714 earlier time, for replay debugging.
716 add-inferior [-copies <N>] [-exec <FILENAME>]
719 clone-inferior [-copies <N>] [ID]
720 Make a new inferior ready to execute the same program another
726 maint info program-spaces
727 List the program spaces loaded into GDB.
729 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
730 show remote interrupt-sequence
731 Allow the user to select one of ^C, a BREAK signal or BREAK-g
732 as the sequence to the remote target in order to interrupt the execution.
733 Ctrl-C is a default. Some system prefers BREAK which is high level of
734 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
735 Magic SysRq g. It is BREAK signal and character 'g'.
737 set remote interrupt-on-connect [on | off]
738 show remote interrupt-on-connect
739 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
740 remote target when gdb connects to it. This is needed when you debug
743 set remotebreak [on | off]
745 Deprecated. Use "set/show remote interrupt-sequence" instead.
747 tvariable $NAME [ = EXP ]
748 Create or modify a trace state variable.
751 List trace state variables and their values.
753 delete tvariable $NAME ...
754 Delete one or more trace state variables.
757 Evaluate the given expressions without collecting anything into the
758 trace buffer. (Valid in tracepoint actions only.)
760 ftrace FN / FILE:LINE / *ADDR
761 Define a fast tracepoint at the given function, line, or address.
763 * New expression syntax
765 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
766 GDB now parses 0b101010 identically with 42.
770 set follow-exec-mode new|same
771 show follow-exec-mode
772 Control whether GDB reuses the same inferior across an exec call or
773 creates a new one. This is useful to be able to restart the old
774 executable after the inferior having done an exec call.
776 set default-collect EXPR, ...
778 Define a list of expressions to be collected at each tracepoint.
779 This is a useful way to ensure essential items are not overlooked,
780 such as registers or a critical global variable.
782 set disconnected-tracing
783 show disconnected-tracing
784 If set to 1, the target is instructed to continue tracing if it
785 loses its connection to GDB. If 0, the target is to stop tracing
788 set circular-trace-buffer
789 show circular-trace-buffer
790 If set to on, the target is instructed to use a circular trace buffer
791 and discard the oldest trace frames instead of stopping the trace due
792 to a full trace buffer. If set to off, the trace stops when the buffer
793 fills up. Some targets may not support this.
795 set script-extension off|soft|strict
796 show script-extension
797 If set to "off", the debugger does not perform any script language
798 recognition, and all sourced files are assumed to be GDB scripts.
799 If set to "soft" (the default), files are sourced according to
800 filename extension, falling back to GDB scripts if the first
802 If set to "strict", files are sourced according to filename extension.
804 set ada trust-PAD-over-XVS on|off
805 show ada trust-PAD-over-XVS
806 If off, activate a workaround against a bug in the debugging information
807 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
808 the GCC sources for more information about the GNAT encoding and
809 PAD types in particular). It is always safe to set this option to
810 off, but this introduces a slight performance penalty. The default
813 * Python API Improvements
815 ** GDB provides the new class gdb.LazyString. This is useful in
816 some pretty-printing cases. The new method gdb.Value.lazy_string
817 provides a simple way to create objects of this type.
819 ** The fields returned by gdb.Type.fields now have an
820 `is_base_class' attribute.
822 ** The new method gdb.Type.range returns the range of an array type.
824 ** The new method gdb.parse_and_eval can be used to parse and
825 evaluate an expression.
830 Define a trace state variable.
833 Get the current value of a trace state variable.
836 Set desired tracing behavior upon disconnection.
839 Set the trace buffer to be linear or circular.
842 Get data about the tracepoints currently in use.
846 Process record now works correctly with hardware watchpoints.
848 Multiple bug fixes have been made to the mips-irix port, making it
849 much more reliable. In particular:
850 - Debugging threaded applications is now possible again. Previously,
851 GDB would hang while starting the program, or while waiting for
852 the program to stop at a breakpoint.
853 - Attaching to a running process no longer hangs.
854 - An error occurring while loading a core file has been fixed.
855 - Changing the value of the PC register now works again. This fixes
856 problems observed when using the "jump" command, or when calling
857 a function from GDB, or even when assigning a new value to $pc.
858 - With the "finish" and "return" commands, the return value for functions
859 returning a small array is now correctly printed.
860 - It is now possible to break on shared library code which gets executed
861 during a shared library init phase (code executed while executing
862 their .init section). Previously, the breakpoint would have no effect.
863 - GDB is now able to backtrace through the signal handler for
864 non-threaded programs.
866 PIE (Position Independent Executable) programs debugging is now supported.
867 This includes debugging execution of PIC (Position Independent Code) shared
868 libraries although for that, it should be possible to run such libraries as an
871 *** Changes in GDB 7.0
873 * GDB now has an interface for JIT compilation. Applications that
874 dynamically generate code can create symbol files in memory and register
875 them with GDB. For users, the feature should work transparently, and
876 for JIT developers, the interface is documented in the GDB manual in the
877 "JIT Compilation Interface" chapter.
879 * Tracepoints may now be conditional. The syntax is as for
880 breakpoints; either an "if" clause appended to the "trace" command,
881 or the "condition" command is available. GDB sends the condition to
882 the target for evaluation using the same bytecode format as is used
883 for tracepoint actions.
885 * The disassemble command now supports: an optional /r modifier, print the
886 raw instructions in hex as well as in symbolic form, and an optional /m
887 modifier to print mixed source+assembly.
889 * Process record and replay
891 In a architecture environment that supports ``process record and
892 replay'', ``process record and replay'' target can record a log of
893 the process execution, and replay it with both forward and reverse
896 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
897 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
898 set execution-direction {forward|reverse}, for targets that support
901 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
902 feature is available with a native GDB running on kernel version
905 * GDB now has support for multi-byte and wide character sets on the
906 target. Strings whose character type is wchar_t, char16_t, or
907 char32_t are now correctly printed. GDB supports wide- and unicode-
908 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
909 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
910 `printf'. This feature requires iconv to work properly; if your
911 system does not have a working iconv, GDB can use GNU libiconv. See
912 the installation instructions for more information.
914 * GDB now supports automatic retrieval of shared library files from
915 remote targets. To use this feature, specify a system root that begins
916 with the `remote:' prefix, either via the `set sysroot' command or via
917 the `--with-sysroot' configure-time option.
919 * "info sharedlibrary" now takes an optional regex of libraries to show,
920 and it now reports if a shared library has no debugging information.
922 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
923 now complete on file names.
925 * When completing in expressions, gdb will attempt to limit
926 completions to allowable structure or union fields, where appropriate.
927 For instance, consider:
929 # struct example { int f1; double f2; };
930 # struct example variable;
933 If the user types TAB at the end of this command line, the available
934 completions will be "f1" and "f2".
936 * Inlined functions are now supported. They show up in backtraces, and
937 the "step", "next", and "finish" commands handle them automatically.
939 * GDB now supports the token-splicing (##) and stringification (#)
940 operators when expanding macros. It also supports variable-arity
943 * GDB now supports inspecting extra signal information, exported by
944 the new $_siginfo convenience variable. The feature is currently
945 implemented on linux ARM, i386 and amd64.
947 * GDB can now display the VFP floating point registers and NEON vector
948 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
949 can provide these registers (requires Linux 2.6.30 or later). Remote
950 and simulator targets may also provide them.
955 Search memory for a sequence of bytes.
958 Turn off `+'/`-' protocol acknowledgments to permit more efficient
959 operation over reliable transport links. Use of this packet is
960 controlled by the `set remote noack-packet' command.
963 Kill the process with the specified process ID. Use this in preference
964 to `k' when multiprocess protocol extensions are supported.
967 Obtains additional operating system information
971 Read or write additional signal information.
973 * Removed remote protocol undocumented extension
975 An undocumented extension to the remote protocol's `S' stop reply
976 packet that permited the stub to pass a process id was removed.
977 Remote servers should use the `T' stop reply packet instead.
979 * GDB now supports multiple function calling conventions according to the
980 DWARF-2 DW_AT_calling_convention function attribute.
982 * The SH target utilizes the aforementioned change to distinguish between gcc
983 and Renesas calling convention. It also adds the new CLI commands
984 `set/show sh calling-convention'.
986 * GDB can now read compressed debug sections, as produced by GNU gold
987 with the --compress-debug-sections=zlib flag.
989 * 64-bit core files are now supported on AIX.
991 * Thread switching is now supported on Tru64.
993 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
994 which will be allocated using malloc later in program execution.
996 * The qXfer:libraries:read remote procotol packet now allows passing a
997 list of section offsets.
999 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1000 conditions handling signals delivered during attach or thread creation
1001 have also been fixed.
1003 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1004 From the user's standpoint, all unqualified instances of True and False
1005 are treated as the standard definitions, regardless of context.
1007 * GDB now parses C++ symbol and type names more flexibly. For
1010 template<typename T> class C { };
1013 GDB will now correctly handle all of:
1015 ptype C<char const *>
1016 ptype C<char const*>
1017 ptype C<const char *>
1018 ptype C<const char*>
1020 * New features in the GDB remote stub, gdbserver
1022 - The "--wrapper" command-line argument tells gdbserver to use a
1023 wrapper program to launch programs for debugging.
1025 - On PowerPC and S/390 targets, it is now possible to use a single
1026 gdbserver executable to debug both 32-bit and 64-bit programs.
1027 (This requires gdbserver itself to be built as a 64-bit executable.)
1029 - gdbserver uses the new noack protocol mode for TCP connections to
1030 reduce communications latency, if also supported and enabled in GDB.
1032 - Support for the sparc64-linux-gnu target is now included in
1035 - The amd64-linux build of gdbserver now supports debugging both
1036 32-bit and 64-bit programs.
1038 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1039 now support hardware watchpoints, and will use them automatically
1044 GDB now has support for scripting using Python. Whether this is
1045 available is determined at configure time.
1047 New GDB commands can now be written in Python.
1049 * Ada tasking support
1051 Ada tasks can now be inspected in GDB. The following commands have
1055 Print the list of Ada tasks.
1057 Print detailed information about task number N.
1059 Print the task number of the current task.
1061 Switch the context of debugging to task number N.
1063 * Support for user-defined prefixed commands. The "define" command can
1064 add new commands to existing prefixes, e.g. "target".
1066 * Multi-inferior, multi-process debugging.
1068 GDB now has generalized support for multi-inferior debugging. See
1069 "Debugging Multiple Inferiors" in the manual for more information.
1070 Although availability still depends on target support, the command
1071 set is more uniform now. The GNU/Linux specific multi-forks support
1072 has been migrated to this new framework. This implied some user
1073 visible changes; see "New commands" and also "Removed commands"
1076 * Target descriptions can now describe the target OS ABI. See the
1077 "Target Description Format" section in the user manual for more
1080 * Target descriptions can now describe "compatible" architectures
1081 to indicate that the target can execute applications for a different
1082 architecture in addition to those for the main target architecture.
1083 See the "Target Description Format" section in the user manual for
1086 * Multi-architecture debugging.
1088 GDB now includes general supports for debugging applications on
1089 hybrid systems that use more than one single processor architecture
1090 at the same time. Each such hybrid architecture still requires
1091 specific support to be added. The only hybrid architecture supported
1092 in this version of GDB is the Cell Broadband Engine.
1094 * GDB now supports integrated debugging of Cell/B.E. applications that
1095 use both the PPU and SPU architectures. To enable support for hybrid
1096 Cell/B.E. debugging, you need to configure GDB to support both the
1097 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1098 --enable-targets configure option.
1100 * Non-stop mode debugging.
1102 For some targets, GDB now supports an optional mode of operation in
1103 which you can examine stopped threads while other threads continue
1104 to execute freely. This is referred to as non-stop mode, with the
1105 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1106 section in the user manual for more information.
1108 To be able to support remote non-stop debugging, a remote stub needs
1109 to implement the non-stop mode remote protocol extensions, as
1110 described in the "Remote Non-Stop" section of the user manual. The
1111 GDB remote stub, gdbserver, has been adjusted to support these
1112 extensions on linux targets.
1114 * New commands (for set/show, see "New options" below)
1116 catch syscall [NAME(S) | NUMBER(S)]
1117 Catch system calls. Arguments, which should be names of system
1118 calls or their numbers, mean catch only those syscalls. Without
1119 arguments, every syscall will be caught. When the inferior issues
1120 any of the specified syscalls, GDB will stop and announce the system
1121 call, both when it is called and when its call returns. This
1122 feature is currently available with a native GDB running on the
1123 Linux Kernel, under the following architectures: x86, x86_64,
1124 PowerPC and PowerPC64.
1126 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1128 Search memory for a sequence of bytes.
1130 maint set python print-stack
1131 maint show python print-stack
1132 Show a stack trace when an error is encountered in a Python script.
1135 Invoke CODE by passing it to the Python interpreter.
1140 These allow macros to be defined, undefined, and listed
1144 Show operating system information about processes.
1147 List the inferiors currently under GDB's control.
1150 Switch focus to inferior number NUM.
1153 Detach from inferior number NUM.
1156 Kill inferior number NUM.
1160 set spu stop-on-load
1161 show spu stop-on-load
1162 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1164 set spu auto-flush-cache
1165 show spu auto-flush-cache
1166 Control whether to automatically flush the software-managed cache
1167 during Cell/B.E. debugging.
1169 set sh calling-convention
1170 show sh calling-convention
1171 Control the calling convention used when calling SH target functions.
1174 show debug timestamp
1175 Control display of timestamps with GDB debugging output.
1177 set disassemble-next-line
1178 show disassemble-next-line
1179 Control display of disassembled source lines or instructions when
1182 set remote noack-packet
1183 show remote noack-packet
1184 Set/show the use of remote protocol QStartNoAckMode packet. See above
1185 under "New remote packets."
1187 set remote query-attached-packet
1188 show remote query-attached-packet
1189 Control use of remote protocol `qAttached' (query-attached) packet.
1191 set remote read-siginfo-object
1192 show remote read-siginfo-object
1193 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1196 set remote write-siginfo-object
1197 show remote write-siginfo-object
1198 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1201 set remote reverse-continue
1202 show remote reverse-continue
1203 Control use of remote protocol 'bc' (reverse-continue) packet.
1205 set remote reverse-step
1206 show remote reverse-step
1207 Control use of remote protocol 'bs' (reverse-step) packet.
1209 set displaced-stepping
1210 show displaced-stepping
1211 Control displaced stepping mode. Displaced stepping is a way to
1212 single-step over breakpoints without removing them from the debuggee.
1213 Also known as "out-of-line single-stepping".
1216 show debug displaced
1217 Control display of debugging info for displaced stepping.
1219 maint set internal-error
1220 maint show internal-error
1221 Control what GDB does when an internal error is detected.
1223 maint set internal-warning
1224 maint show internal-warning
1225 Control what GDB does when an internal warning is detected.
1230 Use a wrapper program to launch programs for debugging.
1232 set multiple-symbols (all|ask|cancel)
1233 show multiple-symbols
1234 The value of this variable can be changed to adjust the debugger behavior
1235 when an expression or a breakpoint location contains an ambiguous symbol
1236 name (an overloaded function name, for instance).
1238 set breakpoint always-inserted
1239 show breakpoint always-inserted
1240 Keep breakpoints always inserted in the target, as opposed to inserting
1241 them when resuming the target, and removing them when the target stops.
1242 This option can improve debugger performance on slow remote targets.
1244 set arm fallback-mode (arm|thumb|auto)
1245 show arm fallback-mode
1246 set arm force-mode (arm|thumb|auto)
1248 These commands control how ARM GDB determines whether instructions
1249 are ARM or Thumb. The default for both settings is auto, which uses
1250 the current CPSR value for instructions without symbols; previous
1251 versions of GDB behaved as if "set arm fallback-mode arm".
1253 set disable-randomization
1254 show disable-randomization
1255 Standalone programs run with the virtual address space randomization enabled
1256 by default on some platforms. This option keeps the addresses stable across
1257 multiple debugging sessions.
1261 Control whether other threads are stopped or not when some thread hits
1266 Requests that asynchronous execution is enabled in the target, if available.
1267 In this case, it's possible to resume target in the background, and interact
1268 with GDB while the target is running. "show target-async" displays the
1269 current state of asynchronous execution of the target.
1271 set target-wide-charset
1272 show target-wide-charset
1273 The target-wide-charset is the name of the character set that GDB
1274 uses when printing characters whose type is wchar_t.
1276 set tcp auto-retry (on|off)
1278 set tcp connect-timeout
1279 show tcp connect-timeout
1280 These commands allow GDB to retry failed TCP connections to a remote stub
1281 with a specified timeout period; this is useful if the stub is launched
1282 in parallel with GDB but may not be ready to accept connections immediately.
1284 set libthread-db-search-path
1285 show libthread-db-search-path
1286 Control list of directories which GDB will search for appropriate
1289 set schedule-multiple (on|off)
1290 show schedule-multiple
1291 Allow GDB to resume all threads of all processes or only threads of
1292 the current process.
1296 Use more aggressive caching for accesses to the stack. This improves
1297 performance of remote debugging (particularly backtraces) without
1298 affecting correctness.
1300 set interactive-mode (on|off|auto)
1301 show interactive-mode
1302 Control whether GDB runs in interactive mode (on) or not (off).
1303 When in interactive mode, GDB waits for the user to answer all
1304 queries. Otherwise, GDB does not wait and assumes the default
1305 answer. When set to auto (the default), GDB determines which
1306 mode to use based on the stdin settings.
1311 For program forks, this is replaced by the new more generic `info
1312 inferiors' command. To list checkpoints, you can still use the
1313 `info checkpoints' command, which was an alias for the `info forks'
1317 Replaced by the new `inferior' command. To switch between
1318 checkpoints, you can still use the `restart' command, which was an
1319 alias for the `fork' command.
1322 This is removed, since some targets don't have a notion of
1323 processes. To switch between processes, you can still use the
1324 `inferior' command using GDB's own inferior number.
1327 For program forks, this is replaced by the new more generic `kill
1328 inferior' command. To delete a checkpoint, you can still use the
1329 `delete checkpoint' command, which was an alias for the `delete
1333 For program forks, this is replaced by the new more generic `detach
1334 inferior' command. To detach a checkpoint, you can still use the
1335 `detach checkpoint' command, which was an alias for the `detach
1338 * New native configurations
1340 x86/x86_64 Darwin i[34567]86-*-darwin*
1342 x86_64 MinGW x86_64-*-mingw*
1346 Lattice Mico32 lm32-*
1347 x86 DICOS i[34567]86-*-dicos*
1348 x86_64 DICOS x86_64-*-dicos*
1351 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1352 (mingw32ce) debugging.
1358 These commands were actually not implemented on any target.
1360 *** Changes in GDB 6.8
1362 * New native configurations
1364 NetBSD/hppa hppa*-*netbsd*
1365 Xtensa GNU/Linux xtensa*-*-linux*
1369 NetBSD/hppa hppa*-*-netbsd*
1370 Xtensa GNU/Lunux xtensa*-*-linux*
1372 * Change in command line behavior -- corefiles vs. process ids.
1374 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1375 attaching to process NUMBER fails, GDB no longer attempts to open a
1376 core file named NUMBER. Attaching to a program using the -c option
1377 is no longer supported. Instead, use the '-p' or '--pid' options.
1379 * GDB can now be built as a native debugger for debugging Windows x86
1380 (mingw32) Portable Executable (PE) programs.
1382 * Pending breakpoints no longer change their number when their address
1385 * GDB now supports breakpoints with multiple locations,
1386 including breakpoints on C++ constructors, inside C++ templates,
1387 and in inlined functions.
1389 * GDB's ability to debug optimized code has been improved. GDB more
1390 accurately identifies function bodies and lexical blocks that occupy
1391 more than one contiguous range of addresses.
1393 * Target descriptions can now describe registers for PowerPC.
1395 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1396 registers on PowerPC targets.
1398 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1399 targets even when the libthread_db library is not available.
1401 * The GDB remote stub, gdbserver, now supports the new file transfer
1402 commands (remote put, remote get, and remote delete).
1404 * The GDB remote stub, gdbserver, now supports run and attach in
1405 extended-remote mode.
1407 * hppa*64*-*-hpux11* target broken
1408 The debugger is unable to start a program and fails with the following
1409 error: "Error trying to get information about dynamic linker".
1410 The gdb-6.7 release is also affected.
1412 * GDB now supports the --enable-targets= configure option to allow
1413 building a single GDB executable that supports multiple remote
1414 target architectures.
1416 * GDB now supports debugging C and C++ programs which use the
1417 Decimal Floating Point extension. In addition, the PowerPC target
1418 now has a set of pseudo-registers to inspect decimal float values
1419 stored in two consecutive float registers.
1421 * The -break-insert MI command can optionally create pending
1424 * Improved support for debugging Ada
1425 Many improvements to the Ada language support have been made. These
1427 - Better support for Ada2005 interface types
1428 - Improved handling of arrays and slices in general
1429 - Better support for Taft-amendment types
1430 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1432 - Improved command completion in Ada
1435 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1440 set print frame-arguments (all|scalars|none)
1441 show print frame-arguments
1442 The value of this variable can be changed to control which argument
1443 values should be printed by the debugger when displaying a frame.
1448 Transfer files to and from a remote target, and delete remote files.
1455 Transfer files to and from a remote target, and delete remote files.
1457 * New remote packets
1464 Open, close, read, write, and delete files on the remote system.
1467 Attach to an existing process on the remote system, in extended-remote
1471 Run a new process on the remote system, in extended-remote mode.
1473 *** Changes in GDB 6.7
1475 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1476 bfd, libiberty and opcodes, as revealed by static analysis donated by
1477 Coverity, Inc. (http://scan.coverity.com).
1479 * When looking up multiply-defined global symbols, GDB will now prefer the
1480 symbol definition in the current shared library if it was built using the
1481 -Bsymbolic linker option.
1483 * When the Text User Interface (TUI) is not configured, GDB will now
1484 recognize the -tui command-line option and print a message that the TUI
1487 * The GDB remote stub, gdbserver, now has lower overhead for high
1488 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1490 * GDB for MIPS targets now autodetects whether a remote target provides
1491 32-bit or 64-bit register values.
1493 * Support for C++ member pointers has been improved.
1495 * GDB now understands XML target descriptions, which specify the
1496 target's overall architecture. GDB can read a description from
1497 a local file or over the remote serial protocol.
1499 * Vectors of single-byte data use a new integer type which is not
1500 automatically displayed as character or string data.
1502 * The /s format now works with the print command. It displays
1503 arrays of single-byte integers and pointers to single-byte integers
1506 * Target descriptions can now describe target-specific registers,
1507 for architectures which have implemented the support (currently
1508 only ARM, M68K, and MIPS).
1510 * GDB and the GDB remote stub, gdbserver, now support the XScale
1513 * The GDB remote stub, gdbserver, has been updated to support
1514 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1515 has been rewritten to use the standard GDB remote protocol.
1517 * GDB can now step into C++ functions which are called through thunks.
1519 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1521 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1522 layout. It also supports a TextSeg= and DataSeg= response when only
1523 segment base addresses (rather than offsets) are available.
1525 * The /i format now outputs any trailing branch delay slot instructions
1526 immediately following the last instruction within the count specified.
1528 * The GDB remote protocol "T" stop reply packet now supports a
1529 "library" response. Combined with the new "qXfer:libraries:read"
1530 packet, this response allows GDB to debug shared libraries on targets
1531 where the operating system manages the list of loaded libraries (e.g.
1532 Windows and SymbianOS).
1534 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1535 (DLLs) on Windows and Windows CE targets.
1537 * GDB now supports a faster verification that a .debug file matches its binary
1538 according to its build-id signature, if the signature is present.
1544 Enable or disable hardware flow control (RTS/CTS) on the serial port
1545 when debugging using remote targets.
1547 set mem inaccessible-by-default
1548 show mem inaccessible-by-default
1549 If the target supplies a memory map, for instance via the remote
1550 protocol's "qXfer:memory-map:read" packet, setting this variable
1551 prevents GDB from accessing memory outside the memory map. This
1552 is useful for targets with memory mapped registers or which react
1553 badly to accesses of unmapped address space.
1555 set breakpoint auto-hw
1556 show breakpoint auto-hw
1557 If the target supplies a memory map, for instance via the remote
1558 protocol's "qXfer:memory-map:read" packet, setting this variable
1559 lets GDB use hardware breakpoints automatically for memory regions
1560 where it can not use software breakpoints. This covers both the
1561 "break" command and internal breakpoints used for other commands
1562 including "next" and "finish".
1565 catch exception unhandled
1566 Stop the program execution when Ada exceptions are raised.
1569 Stop the program execution when an Ada assertion failed.
1573 Set an alternate system root for target files. This is a more
1574 general version of "set solib-absolute-prefix", which is now
1575 an alias to "set sysroot".
1578 Provide extended SPU facility status information. This set of
1579 commands is available only when debugging the Cell/B.E. SPU
1582 * New native configurations
1584 OpenBSD/sh sh*-*openbsd*
1587 unset tdesc filename
1589 Use the specified local file as an XML target description, and do
1590 not query the target for its built-in description.
1594 OpenBSD/sh sh*-*-openbsd*
1595 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1596 Toshiba Media Processor mep-elf
1598 * New remote packets
1601 Ignore the specified signals; pass them directly to the debugged program
1602 without stopping other threads or reporting them to GDB.
1604 qXfer:features:read:
1605 Read an XML target description from the target, which describes its
1610 Read or write contents of an spufs file on the target system. These
1611 packets are available only on the Cell/B.E. SPU architecture.
1613 qXfer:libraries:read:
1614 Report the loaded shared libraries. Combined with new "T" packet
1615 response, this packet allows GDB to debug shared libraries on
1616 targets where the operating system manages the list of loaded
1617 libraries (e.g. Windows and SymbianOS).
1621 Support for these obsolete configurations has been removed.
1629 i[34567]86-*-lynxos*
1630 i[34567]86-*-netware*
1631 i[34567]86-*-sco3.2v5*
1632 i[34567]86-*-sco3.2v4*
1634 i[34567]86-*-sysv4.2*
1637 i[34567]86-*-unixware2*
1638 i[34567]86-*-unixware*
1647 * Other removed features
1654 Various m68k-only ROM monitors.
1661 Various Renesas ROM monitors and debugging interfaces for SH and
1666 Support for a Macraigor serial interface to on-chip debugging.
1667 GDB does not directly support the newer parallel or USB
1672 A debug information format. The predecessor to DWARF 2 and
1673 DWARF 3, which are still supported.
1675 Support for the HP aCC compiler on HP-UX/PA-RISC
1677 SOM-encapsulated symbolic debugging information, automatic
1678 invocation of pxdb, and the aCC custom C++ ABI. This does not
1679 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1680 with aCC can still be debugged on an assembly level.
1682 MIPS ".pdr" sections
1684 A MIPS-specific format used to describe stack frame layout
1685 in debugging information.
1689 GDB could work with an older version of Guile to debug
1690 the interpreter and Scheme programs running in it.
1692 set mips stack-arg-size
1693 set mips saved-gpreg-size
1695 Use "set mips abi" to control parameter passing for MIPS.
1697 *** Changes in GDB 6.6
1702 Cell Broadband Engine SPU spu-elf
1704 * GDB can now be configured as a cross-debugger targeting native Windows
1705 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1706 running on a Windows system over TCP/IP to debug Windows programs.
1708 * The GDB remote stub, gdbserver, has been updated to support Windows and
1709 Cygwin debugging. Both single-threaded and multi-threaded programs are
1712 * The "set trust-readonly-sections" command works again. This command was
1713 broken in GDB 6.3, 6.4, and 6.5.
1715 * The "load" command now supports writing to flash memory, if the remote
1716 stub provides the required support.
1718 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1719 longer requires symbolic debug information (e.g. DWARF-2).
1724 unset substitute-path
1725 show substitute-path
1726 Manage a list of substitution rules that GDB uses to rewrite the name
1727 of the directories where the sources are located. This can be useful
1728 for instance when the sources were moved to a different location
1729 between compilation and debugging.
1733 Print each CLI command as it is executed. Each command is prefixed with
1734 a number of `+' symbols representing the nesting depth.
1735 The source command now has a `-v' option to enable the same feature.
1739 The ARM Demon monitor support (RDP protocol, "target rdp").
1741 Kernel Object Display, an embedded debugging feature which only worked with
1742 an obsolete version of Cisco IOS.
1744 The 'set download-write-size' and 'show download-write-size' commands.
1746 * New remote packets
1749 Tell a stub about GDB client features, and request remote target features.
1750 The first feature implemented is PacketSize, which allows the target to
1751 specify the size of packets it can handle - to minimize the number of
1752 packets required and improve performance when connected to a remote
1756 Fetch an OS auxilliary vector from the remote stub. This packet is a
1757 more efficient replacement for qPart:auxv:read.
1759 qXfer:memory-map:read:
1760 Fetch a memory map from the remote stub, including information about
1761 RAM, ROM, and flash memory devices.
1766 Erase and program a flash memory device.
1768 * Removed remote packets
1771 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1772 used it, and only gdbserver implemented it.
1774 *** Changes in GDB 6.5
1778 Renesas M32C/M16C m32c-elf
1780 Morpho Technologies ms1 ms1-elf
1784 init-if-undefined Initialize a convenience variable, but
1785 only if it doesn't already have a value.
1787 The following commands are presently only implemented for native GNU/Linux:
1789 checkpoint Save a snapshot of the program state.
1791 restart <n> Return the program state to a
1792 previously saved state.
1794 info checkpoints List currently saved checkpoints.
1796 delete-checkpoint <n> Delete a previously saved checkpoint.
1798 set|show detach-on-fork Tell gdb whether to detach from a newly
1799 forked process, or to keep debugging it.
1801 info forks List forks of the user program that
1802 are available to be debugged.
1804 fork <n> Switch to debugging one of several
1805 forks of the user program that are
1806 available to be debugged.
1808 delete-fork <n> Delete a fork from the list of forks
1809 that are available to be debugged (and
1810 kill the forked process).
1812 detach-fork <n> Delete a fork from the list of forks
1813 that are available to be debugged (and
1814 allow the process to continue).
1818 Morpho Technologies ms2 ms1-elf
1820 * Improved Windows host support
1822 GDB now builds as a cross debugger hosted on i686-mingw32, including
1823 native console support, and remote communications using either
1824 network sockets or serial ports.
1826 * Improved Modula-2 language support
1828 GDB can now print most types in the Modula-2 syntax. This includes:
1829 basic types, set types, record types, enumerated types, range types,
1830 pointer types and ARRAY types. Procedure var parameters are correctly
1831 printed and hexadecimal addresses and character constants are also
1832 written in the Modula-2 syntax. Best results can be obtained by using
1833 GNU Modula-2 together with the -gdwarf-2 command line option.
1837 The ARM rdi-share module.
1839 The Netware NLM debug server.
1841 *** Changes in GDB 6.4
1843 * New native configurations
1845 OpenBSD/arm arm*-*-openbsd*
1846 OpenBSD/mips64 mips64-*-openbsd*
1850 Morpho Technologies ms1 ms1-elf
1852 * New command line options
1854 --batch-silent As for --batch, but totally silent.
1855 --return-child-result The debugger will exist with the same value
1856 the child (debugged) program exited with.
1857 --eval-command COMMAND, -ex COMMAND
1858 Execute a single GDB CLI command. This may be
1859 specified multiple times and in conjunction
1860 with the --command (-x) option.
1862 * Deprecated commands removed
1864 The following commands, that were deprecated in 2000, have been
1868 set|show arm disassembly-flavor set|show arm disassembler
1869 othernames set arm disassembler
1870 set|show remotedebug set|show debug remote
1871 set|show archdebug set|show debug arch
1872 set|show eventdebug set|show debug event
1875 * New BSD user-level threads support
1877 It is now possible to debug programs using the user-level threads
1878 library on OpenBSD and FreeBSD. Currently supported (target)
1881 FreeBSD/amd64 x86_64-*-freebsd*
1882 FreeBSD/i386 i386-*-freebsd*
1883 OpenBSD/i386 i386-*-openbsd*
1885 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1886 are not yet supported.
1888 * New support for Matsushita MN10300 w/sim added
1889 (Work in progress). mn10300-elf.
1891 * REMOVED configurations and files
1893 VxWorks and the XDR protocol *-*-vxworks
1894 Motorola MCORE mcore-*-*
1895 National Semiconductor NS32000 ns32k-*-*
1897 * New "set print array-indexes" command
1899 After turning this setting "on", GDB prints the index of each element
1900 when displaying arrays. The default is "off" to preserve the previous
1903 * VAX floating point support
1905 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1907 * User-defined command support
1909 In addition to using $arg0..$arg9 for argument passing, it is now possible
1910 to use $argc to determine now many arguments have been passed. See the
1911 section on user-defined commands in the user manual for more information.
1913 *** Changes in GDB 6.3:
1915 * New command line option
1917 GDB now accepts -l followed by a number to set the timeout for remote
1920 * GDB works with GCC -feliminate-dwarf2-dups
1922 GDB now supports a more compact representation of DWARF-2 debug
1923 information using DW_FORM_ref_addr references. These are produced
1924 by GCC with the option -feliminate-dwarf2-dups and also by some
1925 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1926 to use -feliminate-dwarf2-dups.
1928 * Internationalization
1930 When supported by the host system, GDB will be built with
1931 internationalization (libintl). The task of marking up the sources is
1932 continued, we're looking forward to our first translation.
1936 Initial support for debugging programs compiled with the GNAT
1937 implementation of the Ada programming language has been integrated
1938 into GDB. In this release, support is limited to expression evaluation.
1940 * New native configurations
1942 GNU/Linux/m32r m32r-*-linux-gnu
1946 GDB's remote protocol now includes support for the 'p' packet. This
1947 packet is used to fetch individual registers from a remote inferior.
1949 * END-OF-LIFE registers[] compatibility module
1951 GDB's internal register infrastructure has been completely rewritten.
1952 The new infrastructure making possible the implementation of key new
1953 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1956 GDB 6.3 will be the last release to include the the registers[]
1957 compatibility module that allowed out-of-date configurations to
1958 continue to work. This change directly impacts the following
1968 powerpc bdm protocol
1970 Unless there is activity to revive these configurations, they will be
1971 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1973 * OBSOLETE configurations and files
1975 Configurations that have been declared obsolete in this release have
1976 been commented out. Unless there is activity to revive these
1977 configurations, the next release of GDB will have their sources
1978 permanently REMOVED.
1987 *** Changes in GDB 6.2.1:
1989 * MIPS `break main; run' gave an heuristic-fence-post warning
1991 When attempting to run even a simple program, a warning about
1992 heuristic-fence-post being hit would be reported. This problem has
1995 * MIPS IRIX 'long double' crashed GDB
1997 When examining a long double variable, GDB would get a segmentation
1998 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1999 IRIX long double values).
2003 A bug in the VAX stack code was causing problems with the "next"
2004 command. This problem has been fixed.
2006 *** Changes in GDB 6.2:
2008 * Fix for ``many threads''
2010 On GNU/Linux systems that use the NPTL threads library, a program
2011 rapidly creating and deleting threads would confuse GDB leading to the
2014 ptrace: No such process.
2015 thread_db_get_info: cannot get thread info: generic error
2017 This problem has been fixed.
2019 * "-async" and "-noasync" options removed.
2021 Support for the broken "-noasync" option has been removed (it caused
2024 * New ``start'' command.
2026 This command runs the program until the begining of the main procedure.
2028 * New BSD Kernel Data Access Library (libkvm) interface
2030 Using ``target kvm'' it is now possible to debug kernel core dumps and
2031 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2032 platforms. Currently supported (native-only) configurations are:
2034 FreeBSD/amd64 x86_64-*-freebsd*
2035 FreeBSD/i386 i?86-*-freebsd*
2036 NetBSD/i386 i?86-*-netbsd*
2037 NetBSD/m68k m68*-*-netbsd*
2038 NetBSD/sparc sparc-*-netbsd*
2039 OpenBSD/amd64 x86_64-*-openbsd*
2040 OpenBSD/i386 i?86-*-openbsd*
2041 OpenBSD/m68k m68*-openbsd*
2042 OpenBSD/sparc sparc-*-openbsd*
2044 * Signal trampoline code overhauled
2046 Many generic problems with GDB's signal handling code have been fixed.
2047 These include: backtraces through non-contiguous stacks; recognition
2048 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2049 call; backtrace through a signal trampoline; step into and out of
2050 signal handlers; and single-stepping in the signal trampoline.
2052 Please note that kernel bugs are a limiting factor here. These
2053 features have been shown to work on an s390 GNU/Linux system that
2054 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2056 * Cygwin support for DWARF 2 added.
2058 * New native configurations
2060 GNU/Linux/hppa hppa*-*-linux*
2061 OpenBSD/hppa hppa*-*-openbsd*
2062 OpenBSD/m68k m68*-*-openbsd*
2063 OpenBSD/m88k m88*-*-openbsd*
2064 OpenBSD/powerpc powerpc-*-openbsd*
2065 NetBSD/vax vax-*-netbsd*
2066 OpenBSD/vax vax-*-openbsd*
2068 * END-OF-LIFE frame compatibility module
2070 GDB's internal frame infrastructure has been completely rewritten.
2071 The new infrastructure making it possible to support key new features
2072 including DWARF 2 Call Frame Information. To aid in the task of
2073 migrating old configurations to this new infrastructure, a
2074 compatibility module, that allowed old configurations to continue to
2075 work, was also included.
2077 GDB 6.2 will be the last release to include this frame compatibility
2078 module. This change directly impacts the following configurations:
2088 Unless there is activity to revive these configurations, they will be
2089 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2091 * REMOVED configurations and files
2093 Sun 3, running SunOS 3 m68*-*-sunos3*
2094 Sun 3, running SunOS 4 m68*-*-sunos4*
2095 Sun 2, running SunOS 3 m68000-*-sunos3*
2096 Sun 2, running SunOS 4 m68000-*-sunos4*
2097 Motorola 680x0 running LynxOS m68*-*-lynxos*
2098 AT&T 3b1/Unix pc m68*-att-*
2099 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2100 decstation mips-dec-* mips-little-*
2101 riscos mips-*-riscos* mips-*-sysv*
2102 sonymips mips-sony-*
2103 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2105 *** Changes in GDB 6.1.1:
2107 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2109 The TUI (Text-mode User Interface) is now built as part of a default
2110 GDB configuration. It is enabled by either selecting the TUI with the
2111 command line option "-i=tui" or by running the separate "gdbtui"
2112 program. For more information on the TUI, see the manual "Debugging
2115 * Pending breakpoint support (also included in GDB 6.1)
2117 Support has been added to allow you to specify breakpoints in shared
2118 libraries that have not yet been loaded. If a breakpoint location
2119 cannot be found, and the "breakpoint pending" option is set to auto,
2120 GDB queries you if you wish to make the breakpoint pending on a future
2121 shared-library load. If and when GDB resolves the breakpoint symbol,
2122 the pending breakpoint is removed as one or more regular breakpoints
2125 Pending breakpoints are very useful for GCJ Java debugging.
2127 * Fixed ISO-C build problems
2129 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2130 non ISO-C code that stopped them being built using a more strict ISO-C
2131 compiler (e.g., IBM's C compiler).
2133 * Fixed build problem on IRIX 5
2135 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2136 wasn't able to compile compile on an IRIX 5 system.
2138 * Added execute permission to gdb/gdbserver/configure
2140 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2141 permission. This bug would cause configure to fail on a number of
2142 systems (Solaris, IRIX). Ref: server/519.
2144 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2146 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2147 has been updated to use constant array sizes.
2149 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2151 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2152 its generated DWARF Call Frame Info. This encoding was causing GDB to
2153 panic, that panic has been fixed. Ref: gdb/1628.
2155 * Fixed a problem when examining parameters in shared library code.
2157 When examining parameters in optimized shared library code generated
2158 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2159 not available''. GDB now correctly displays the variable's value.
2161 *** Changes in GDB 6.1:
2163 * Removed --with-mmalloc
2165 Support for the mmalloc memory manager has been removed, as it
2166 conflicted with the internal gdb byte cache.
2168 * Changes in AMD64 configurations
2170 The AMD64 target now includes the %cs and %ss registers. As a result
2171 the AMD64 remote protocol has changed; this affects the floating-point
2172 and SSE registers. If you rely on those registers for your debugging,
2173 you should upgrade gdbserver on the remote side.
2175 * Revised SPARC target
2177 The SPARC target has been completely revised, incorporating the
2178 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2179 support for LynxOS and SunOS 4 has been dropped. Calling functions
2180 from within GDB on operating systems with a non-executable stack
2181 (Solaris, OpenBSD) now works.
2185 GDB has a new C++ demangler which does a better job on the mangled
2186 names generated by current versions of g++. It also runs faster, so
2187 with this and other changes gdb should now start faster on large C++
2190 * DWARF 2 Location Expressions
2192 GDB support for location expressions has been extended to support function
2193 arguments and frame bases. Older versions of GDB could crash when they
2196 * C++ nested types and namespaces
2198 GDB's support for nested types and namespaces in C++ has been
2199 improved, especially if you use the DWARF 2 debugging format. (This
2200 is the default for recent versions of GCC on most platforms.)
2201 Specifically, if you have a class "Inner" defined within a class or
2202 namespace "Outer", then GDB realizes that the class's name is
2203 "Outer::Inner", not simply "Inner". This should greatly reduce the
2204 frequency of complaints about not finding RTTI symbols. In addition,
2205 if you are stopped at inside of a function defined within a namespace,
2206 GDB modifies its name lookup accordingly.
2208 * New native configurations
2210 NetBSD/amd64 x86_64-*-netbsd*
2211 OpenBSD/amd64 x86_64-*-openbsd*
2212 OpenBSD/alpha alpha*-*-openbsd*
2213 OpenBSD/sparc sparc-*-openbsd*
2214 OpenBSD/sparc64 sparc64-*-openbsd*
2216 * New debugging protocols
2218 M32R with SDI protocol m32r-*-elf*
2220 * "set prompt-escape-char" command deleted.
2222 The command "set prompt-escape-char" has been deleted. This command,
2223 and its very obscure effet on GDB's prompt, was never documented,
2224 tested, nor mentioned in the NEWS file.
2226 * OBSOLETE configurations and files
2228 Configurations that have been declared obsolete in this release have
2229 been commented out. Unless there is activity to revive these
2230 configurations, the next release of GDB will have their sources
2231 permanently REMOVED.
2233 Sun 3, running SunOS 3 m68*-*-sunos3*
2234 Sun 3, running SunOS 4 m68*-*-sunos4*
2235 Sun 2, running SunOS 3 m68000-*-sunos3*
2236 Sun 2, running SunOS 4 m68000-*-sunos4*
2237 Motorola 680x0 running LynxOS m68*-*-lynxos*
2238 AT&T 3b1/Unix pc m68*-att-*
2239 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2240 decstation mips-dec-* mips-little-*
2241 riscos mips-*-riscos* mips-*-sysv*
2242 sonymips mips-sony-*
2243 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2245 * REMOVED configurations and files
2247 SGI Irix-4.x mips-sgi-irix4 or iris4
2248 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2249 Z8000 simulator z8k-zilog-none or z8ksim
2250 Matsushita MN10200 w/simulator mn10200-*-*
2251 H8/500 simulator h8500-hitachi-hms or h8500hms
2252 HP/PA running BSD hppa*-*-bsd*
2253 HP/PA running OSF/1 hppa*-*-osf*
2254 HP/PA Pro target hppa*-*-pro*
2255 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2256 386BSD i[3456]86-*-bsd*
2257 Sequent family i[3456]86-sequent-sysv4*
2258 i[3456]86-sequent-sysv*
2259 i[3456]86-sequent-bsd*
2260 SPARC running LynxOS sparc-*-lynxos*
2261 SPARC running SunOS 4 sparc-*-sunos4*
2262 Tsqware Sparclet sparclet-*-*
2263 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2265 *** Changes in GDB 6.0:
2269 Support for debugging the Objective-C programming language has been
2270 integrated into GDB.
2272 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2274 DWARF 2's Call Frame Information makes available compiler generated
2275 information that more exactly describes the program's run-time stack.
2276 By using this information, GDB is able to provide more robust stack
2279 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2280 have been updated to use a new backtrace mechanism which includes
2281 DWARF 2 CFI support.
2285 GDB's remote protocol has been extended to include support for hosted
2286 file I/O (where the remote target uses GDB's file system). See GDB's
2287 remote protocol documentation for details.
2289 * All targets using the new architecture framework.
2291 All of GDB's targets have been updated to use the new internal
2292 architecture framework. The way is now open for future GDB releases
2293 to include cross-architecture native debugging support (i386 on amd64,
2296 * GNU/Linux's Thread Local Storage (TLS)
2298 GDB now includes support for for the GNU/Linux implementation of
2299 per-thread variables.
2301 * GNU/Linux's Native POSIX Thread Library (NPTL)
2303 GDB's thread code has been updated to work with either the new
2304 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2306 * Separate debug info.
2308 GDB, in conjunction with BINUTILS, now supports a mechanism for
2309 automatically loading debug information from a separate file. Instead
2310 of shipping full debug and non-debug versions of system libraries,
2311 system integrators can now instead ship just the stripped libraries
2312 and optional debug files.
2314 * DWARF 2 Location Expressions
2316 DWARF 2 Location Expressions allow the compiler to more completely
2317 describe the location of variables (even in optimized code) to the
2320 GDB now includes preliminary support for location expressions (support
2321 for DW_OP_piece is still missing).
2325 A number of long standing bugs that caused GDB to die while starting a
2326 Java application have been fixed. GDB's Java support is now
2327 considered "useable".
2329 * GNU/Linux support for fork, vfork, and exec.
2331 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2332 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2335 * GDB supports logging output to a file
2337 There are two new commands, "set logging" and "show logging", which can be
2338 used to capture GDB's output to a file.
2340 * The meaning of "detach" has changed for gdbserver
2342 The "detach" command will now resume the application, as documented. To
2343 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2346 * d10v, m68hc11 `regs' command deprecated
2348 The `info registers' command has been updated so that it displays the
2349 registers using a format identical to the old `regs' command.
2353 A new command, "maint set profile on/off", has been added. This command can
2354 be used to enable or disable profiling while running GDB, to profile a
2355 session or a set of commands. In addition there is a new configure switch,
2356 "--enable-profiling", which will cause GDB to be compiled with profiling
2357 data, for more informative profiling results.
2359 * Default MI syntax changed to "mi2".
2361 The default MI (machine interface) syntax, enabled by the command line
2362 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2363 "mi1", can be enabled by specifying the option "-i=mi1".
2365 Support for the original "mi0" syntax (included in GDB 5.0) has been
2368 Fix for gdb/192: removed extraneous space when displaying frame level.
2369 Fix for gdb/672: update changelist is now output in mi list format.
2370 Fix for gdb/702: a -var-assign that updates the value now shows up
2371 in a subsequent -var-update.
2373 * New native configurations.
2375 FreeBSD/amd64 x86_64-*-freebsd*
2377 * Multi-arched targets.
2379 HP/PA HPUX11 hppa*-*-hpux*
2380 Renesas M32R/D w/simulator m32r-*-elf*
2382 * OBSOLETE configurations and files
2384 Configurations that have been declared obsolete in this release have
2385 been commented out. Unless there is activity to revive these
2386 configurations, the next release of GDB will have their sources
2387 permanently REMOVED.
2389 Z8000 simulator z8k-zilog-none or z8ksim
2390 Matsushita MN10200 w/simulator mn10200-*-*
2391 H8/500 simulator h8500-hitachi-hms or h8500hms
2392 HP/PA running BSD hppa*-*-bsd*
2393 HP/PA running OSF/1 hppa*-*-osf*
2394 HP/PA Pro target hppa*-*-pro*
2395 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2396 Sequent family i[3456]86-sequent-sysv4*
2397 i[3456]86-sequent-sysv*
2398 i[3456]86-sequent-bsd*
2399 Tsqware Sparclet sparclet-*-*
2400 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2402 * REMOVED configurations and files
2405 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2406 IBM AIX PS/2 i[3456]86-*-aix
2407 i386 running Mach 3.0 i[3456]86-*-mach3*
2408 i386 running Mach i[3456]86-*-mach*
2409 i386 running OSF/1 i[3456]86-*osf1mk*
2410 HP/Apollo 68k Family m68*-apollo*-sysv*,
2412 m68*-hp-bsd*, m68*-hp-hpux*
2413 Argonaut Risc Chip (ARC) arc-*-*
2414 Mitsubishi D30V d30v-*-*
2415 Fujitsu FR30 fr30-*-elf*
2416 OS/9000 i[34]86-*-os9k
2417 I960 with MON960 i960-*-coff
2419 * MIPS $fp behavior changed
2421 The convenience variable $fp, for the MIPS, now consistently returns
2422 the address of the current frame's base. Previously, depending on the
2423 context, $fp could refer to either $sp or the current frame's base
2424 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2425 The GNU Source-Level Debugger''.
2427 *** Changes in GDB 5.3:
2429 * GNU/Linux shared library multi-threaded performance improved.
2431 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2432 `/proc', in preference to `ptrace' for memory reads. This may result
2433 in an improvement in the start-up time of multi-threaded, shared
2434 library applications when run under GDB. One GDB user writes: ``loads
2435 shared libs like mad''.
2437 * ``gdbserver'' now supports multi-threaded applications on some targets
2439 Support for debugging multi-threaded applications which use
2440 the GNU/Linux LinuxThreads package has been added for
2441 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2442 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2444 * GDB now supports C/C++ preprocessor macros.
2446 GDB now expands preprocessor macro invocations in C/C++ expressions,
2447 and provides various commands for showing macro definitions and how
2450 The new command `macro expand EXPRESSION' expands any macro
2451 invocations in expression, and shows the result.
2453 The new command `show macro MACRO-NAME' shows the definition of the
2454 macro named MACRO-NAME, and where it was defined.
2456 Most compilers don't include information about macros in the debugging
2457 information by default. In GCC 3.1, for example, you need to compile
2458 your program with the options `-gdwarf-2 -g3'. If the macro
2459 information is present in the executable, GDB will read it.
2461 * Multi-arched targets.
2463 DEC Alpha (partial) alpha*-*-*
2464 DEC VAX (partial) vax-*-*
2466 National Semiconductor NS32000 (partial) ns32k-*-*
2467 Motorola 68000 (partial) m68k-*-*
2468 Motorola MCORE mcore-*-*
2472 Fujitsu FRV architecture added by Red Hat frv*-*-*
2475 * New native configurations
2477 Alpha NetBSD alpha*-*-netbsd*
2478 SH NetBSD sh*-*-netbsdelf*
2479 MIPS NetBSD mips*-*-netbsd*
2480 UltraSPARC NetBSD sparc64-*-netbsd*
2482 * OBSOLETE configurations and files
2484 Configurations that have been declared obsolete in this release have
2485 been commented out. Unless there is activity to revive these
2486 configurations, the next release of GDB will have their sources
2487 permanently REMOVED.
2489 Mitsubishi D30V d30v-*-*
2490 OS/9000 i[34]86-*-os9k
2491 IBM AIX PS/2 i[3456]86-*-aix
2492 Fujitsu FR30 fr30-*-elf*
2493 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2494 Argonaut Risc Chip (ARC) arc-*-*
2495 i386 running Mach 3.0 i[3456]86-*-mach3*
2496 i386 running Mach i[3456]86-*-mach*
2497 i386 running OSF/1 i[3456]86-*osf1mk*
2498 HP/Apollo 68k Family m68*-apollo*-sysv*,
2500 m68*-hp-bsd*, m68*-hp-hpux*
2501 I960 with MON960 i960-*-coff
2503 * OBSOLETE languages
2505 CHILL, a Pascal like language used by telecommunications companies.
2507 * REMOVED configurations and files
2509 AMD 29k family via UDI a29k-amd-udi, udi29k
2510 A29K VxWorks a29k-*-vxworks
2511 AMD 29000 embedded, using EBMON a29k-none-none
2512 AMD 29000 embedded with COFF a29k-none-coff
2513 AMD 29000 embedded with a.out a29k-none-aout
2515 testsuite/gdb.hp/gdb.threads-hp/ directory
2517 * New command "set max-user-call-depth <nnn>"
2519 This command allows the user to limit the call depth of user-defined
2520 commands. The default is 1024.
2522 * Changes in FreeBSD/i386 native debugging.
2524 Support for the "generate-core-file" has been added.
2526 * New commands "dump", "append", and "restore".
2528 These commands allow data to be copied from target memory
2529 to a bfd-format or binary file (dump and append), and back
2530 from a file into memory (restore).
2532 * Improved "next/step" support on multi-processor Alpha Tru64.
2534 The previous single-step mechanism could cause unpredictable problems,
2535 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2536 of a software single-step mechanism prevents this.
2538 *** Changes in GDB 5.2.1:
2546 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2547 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2548 Fix, by Joel Brobecker imported from mainline.
2550 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2551 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2552 Fix, by Fred Fish, imported from mainline.
2554 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2555 Surprisingly enough, it works now.
2556 By Michal Ludvig, imported from mainline.
2558 i386 hardware watchpoint support:
2559 avoid misses on second run for some targets.
2560 By Pierre Muller, imported from mainline.
2562 *** Changes in GDB 5.2:
2564 * New command "set trust-readonly-sections on[off]".
2566 This command is a hint that tells gdb that read-only sections
2567 really are read-only (ie. that their contents will not change).
2568 In this mode, gdb will go to the object file rather than the
2569 target to read memory from read-only sections (such as ".text").
2570 This can be a significant performance improvement on some
2571 (notably embedded) targets.
2573 * New command "generate-core-file" (or "gcore").
2575 This new gdb command allows the user to drop a core file of the child
2576 process state at any time. So far it's been implemented only for
2577 GNU/Linux and Solaris, but should be relatively easily ported to other
2578 hosts. Argument is core file name (defaults to core.<pid>).
2580 * New command line option
2582 GDB now accepts --pid or -p followed by a process id.
2584 * Change in command line behavior -- corefiles vs. process ids.
2586 There is a subtle behavior in the way in which GDB handles
2587 command line arguments. The first non-flag argument is always
2588 a program to debug, but the second non-flag argument may either
2589 be a corefile or a process id. Previously, GDB would attempt to
2590 open the second argument as a corefile, and if that failed, would
2591 issue a superfluous error message and then attempt to attach it as
2592 a process. Now, if the second argument begins with a non-digit,
2593 it will be treated as a corefile. If it begins with a digit,
2594 GDB will attempt to attach it as a process, and if no such process
2595 is found, will then attempt to open it as a corefile.
2597 * Changes in ARM configurations.
2599 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2600 configuration is fully multi-arch.
2602 * New native configurations
2604 ARM NetBSD arm*-*-netbsd*
2605 x86 OpenBSD i[3456]86-*-openbsd*
2606 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2607 Sparc64 running FreeBSD sparc64-*-freebsd*
2611 Sanyo XStormy16 xstormy16-elf
2613 * OBSOLETE configurations and files
2615 Configurations that have been declared obsolete in this release have
2616 been commented out. Unless there is activity to revive these
2617 configurations, the next release of GDB will have their sources
2618 permanently REMOVED.
2620 AMD 29k family via UDI a29k-amd-udi, udi29k
2621 A29K VxWorks a29k-*-vxworks
2622 AMD 29000 embedded, using EBMON a29k-none-none
2623 AMD 29000 embedded with COFF a29k-none-coff
2624 AMD 29000 embedded with a.out a29k-none-aout
2626 testsuite/gdb.hp/gdb.threads-hp/ directory
2628 * REMOVED configurations and files
2630 TI TMS320C80 tic80-*-*
2632 PowerPC Solaris powerpcle-*-solaris*
2633 PowerPC Windows NT powerpcle-*-cygwin32
2634 PowerPC Netware powerpc-*-netware*
2635 Harris/CXUX m88k m88*-harris-cxux*
2636 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2637 ns32k-utek-sysv* ns32k-utek-*
2638 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2639 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2640 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2641 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2642 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2644 * Changes to command line processing
2646 The new `--args' feature can be used to specify command-line arguments
2647 for the inferior from gdb's command line.
2649 * Changes to key bindings
2651 There is a new `operate-and-get-next' function bound to `C-o'.
2653 *** Changes in GDB 5.1.1
2655 Fix compile problem on DJGPP.
2657 Fix a problem with floating-point registers on the i386 being
2660 Fix to stop GDB crashing on .debug_str debug info.
2662 Numerous documentation fixes.
2664 Numerous testsuite fixes.
2666 *** Changes in GDB 5.1:
2668 * New native configurations
2670 Alpha FreeBSD alpha*-*-freebsd*
2671 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2672 MIPS GNU/Linux mips*-*-linux*
2673 MIPS SGI Irix 6.x mips*-sgi-irix6*
2674 ia64 AIX ia64-*-aix*
2675 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2679 Motorola 68HC11 and 68HC12 m68hc11-elf
2681 UltraSparc running GNU/Linux sparc64-*-linux*
2683 * OBSOLETE configurations and files
2685 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2686 Harris/CXUX m88k m88*-harris-cxux*
2687 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2688 ns32k-utek-sysv* ns32k-utek-*
2689 TI TMS320C80 tic80-*-*
2691 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2692 PowerPC Solaris powerpcle-*-solaris*
2693 PowerPC Windows NT powerpcle-*-cygwin32
2694 PowerPC Netware powerpc-*-netware*
2695 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2696 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2697 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2698 Apple Macintosh (MPW) host N/A
2700 stuff.c (Program to stuff files into a specially prepared space in kdb)
2701 kdb-start.c (Main loop for the standalone kernel debugger)
2703 Configurations that have been declared obsolete in this release have
2704 been commented out. Unless there is activity to revive these
2705 configurations, the next release of GDB will have their sources
2706 permanently REMOVED.
2708 * REMOVED configurations and files
2710 Altos 3068 m68*-altos-*
2711 Convex c1-*-*, c2-*-*
2713 ARM RISCix arm-*-* (as host)
2717 * GDB has been converted to ISO C.
2719 GDB's source code has been converted to ISO C. In particular, the
2720 sources are fully protoized, and rely on standard headers being
2725 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2727 * The MI enabled by default.
2729 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2730 revised and enabled by default. Packages which use GDB as a debugging
2731 engine behind a UI or another front end are encouraged to switch to
2732 using the GDB/MI interface, instead of the old annotations interface
2733 which is now deprecated.
2735 * Support for debugging Pascal programs.
2737 GDB now includes support for debugging Pascal programs. The following
2738 main features are supported:
2740 - Pascal-specific data types such as sets;
2742 - automatic recognition of Pascal sources based on file-name
2745 - Pascal-style display of data types, variables, and functions;
2747 - a Pascal expression parser.
2749 However, some important features are not yet supported.
2751 - Pascal string operations are not supported at all;
2753 - there are some problems with boolean types;
2755 - Pascal type hexadecimal constants are not supported
2756 because they conflict with the internal variables format;
2758 - support for Pascal objects and classes is not full yet;
2760 - unlike Pascal, GDB is case-sensitive for symbol names.
2762 * Changes in completion.
2764 Commands such as `shell', `run' and `set args', which pass arguments
2765 to inferior programs, now complete on file names, similar to what
2766 users expect at the shell prompt.
2768 Commands which accept locations, such as `disassemble', `print',
2769 `breakpoint', `until', etc. now complete on filenames as well as
2770 program symbols. Thus, if you type "break foob TAB", and the source
2771 files linked into the programs include `foobar.c', that file name will
2772 be one of the candidates for completion. However, file names are not
2773 considered for completion after you typed a colon that delimits a file
2774 name from a name of a function in that file, as in "break foo.c:bar".
2776 `set demangle-style' completes on available demangling styles.
2778 * New platform-independent commands:
2780 It is now possible to define a post-hook for a command as well as a
2781 hook that runs before the command. For more details, see the
2782 documentation of `hookpost' in the GDB manual.
2784 * Changes in GNU/Linux native debugging.
2786 Support for debugging multi-threaded programs has been completely
2787 revised for all platforms except m68k and sparc. You can now debug as
2788 many threads as your system allows you to have.
2790 Attach/detach is supported for multi-threaded programs.
2792 Support for SSE registers was added for x86. This doesn't work for
2793 multi-threaded programs though.
2795 * Changes in MIPS configurations.
2797 Multi-arch support is enabled for all MIPS configurations.
2799 GDB can now be built as native debugger on SGI Irix 6.x systems for
2800 debugging n32 executables. (Debugging 64-bit executables is not yet
2803 * Unified support for hardware watchpoints in all x86 configurations.
2805 Most (if not all) native x86 configurations support hardware-assisted
2806 breakpoints and watchpoints in a unified manner. This support
2807 implements debug register sharing between watchpoints, which allows to
2808 put a virtually infinite number of watchpoints on the same address,
2809 and also supports watching regions up to 16 bytes with several debug
2812 The new maintenance command `maintenance show-debug-regs' toggles
2813 debugging print-outs in functions that insert, remove, and test
2814 watchpoints and hardware breakpoints.
2816 * Changes in the DJGPP native configuration.
2818 New command ``info dos sysinfo'' displays assorted information about
2819 the CPU, OS, memory, and DPMI server.
2821 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2822 display information about segment descriptors stored in GDT, LDT, and
2825 New commands ``info dos pde'' and ``info dos pte'' display entries
2826 from Page Directory and Page Tables (for now works with CWSDPMI only).
2827 New command ``info dos address-pte'' displays the Page Table entry for
2828 a given linear address.
2830 GDB can now pass command lines longer than 126 characters to the
2831 program being debugged (requires an update to the libdbg.a library
2832 which is part of the DJGPP development kit).
2834 DWARF2 debug info is now supported.
2836 It is now possible to `step' and `next' through calls to `longjmp'.
2838 * Changes in documentation.
2840 All GDB documentation was converted to GFDL, the GNU Free
2841 Documentation License.
2843 Tracepoints-related commands are now fully documented in the GDB
2846 TUI, the Text-mode User Interface, is now documented in the manual.
2848 Tracepoints-related commands are now fully documented in the GDB
2851 The "GDB Internals" manual now has an index. It also includes
2852 documentation of `ui_out' functions, GDB coding standards, x86
2853 hardware watchpoints, and memory region attributes.
2855 * GDB's version number moved to ``version.in''
2857 The Makefile variable VERSION has been replaced by the file
2858 ``version.in''. People creating GDB distributions should update the
2859 contents of this file.
2863 GUD support is now a standard part of the EMACS distribution.
2865 *** Changes in GDB 5.0:
2867 * Improved support for debugging FP programs on x86 targets
2869 Unified and much-improved support for debugging floating-point
2870 programs on all x86 targets. In particular, ``info float'' now
2871 displays the FP registers in the same format on all x86 targets, with
2872 greater level of detail.
2874 * Improvements and bugfixes in hardware-assisted watchpoints
2876 It is now possible to watch array elements, struct members, and
2877 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2878 on x86 targets no longer erroneously trigger when the address is
2881 * Improvements in the native DJGPP version of GDB
2883 The distribution now includes all the scripts and auxiliary files
2884 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2885 machines ``out of the box''.
2887 The DJGPP version can now debug programs that use signals. It is
2888 possible to catch signals that happened in the debuggee, deliver
2889 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2890 would kill the program being debugged.) Programs that hook hardware
2891 interrupts (keyboard, timer, etc.) can also be debugged.
2893 It is now possible to debug DJGPP programs that redirect their
2894 standard handles or switch them to raw (as opposed to cooked) mode, or
2895 even close them. The command ``run < foo > bar'' works as expected,
2896 and ``info terminal'' reports useful information about the debuggee's
2897 terminal, including raw/cooked mode, redirection, etc.
2899 The DJGPP version now uses termios functions for console I/O, which
2900 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2903 DOS-style file names with drive letters are now fully supported by
2906 It is now possible to debug DJGPP programs that switch their working
2907 directory. It is also possible to rerun the debuggee any number of
2908 times without restarting GDB; thus, you can use the same setup,
2909 breakpoints, etc. for many debugging sessions.
2911 * New native configurations
2913 ARM GNU/Linux arm*-*-linux*
2914 PowerPC GNU/Linux powerpc-*-linux*
2918 Motorola MCore mcore-*-*
2919 x86 VxWorks i[3456]86-*-vxworks*
2920 PowerPC VxWorks powerpc-*-vxworks*
2921 TI TMS320C80 tic80-*-*
2923 * OBSOLETE configurations
2925 Altos 3068 m68*-altos-*
2926 Convex c1-*-*, c2-*-*
2928 ARM RISCix arm-*-* (as host)
2931 Configurations that have been declared obsolete will be commented out,
2932 but the code will be left in place. If there is no activity to revive
2933 these configurations before the next release of GDB, the sources will
2934 be permanently REMOVED.
2936 * Gould support removed
2938 Support for the Gould PowerNode and NP1 has been removed.
2940 * New features for SVR4
2942 On SVR4 native platforms (such as Solaris), if you attach to a process
2943 without first loading a symbol file, GDB will now attempt to locate and
2944 load symbols from the running process's executable file.
2946 * Many C++ enhancements
2948 C++ support has been greatly improved. Overload resolution now works properly
2949 in almost all cases. RTTI support is on the way.
2951 * Remote targets can connect to a sub-program
2953 A popen(3) style serial-device has been added. This device starts a
2954 sub-process (such as a stand-alone simulator) and then communicates
2955 with that. The sub-program to run is specified using the syntax
2956 ``|<program> <args>'' vis:
2958 (gdb) set remotedebug 1
2959 (gdb) target extended-remote |mn10300-elf-sim program-args
2961 * MIPS 64 remote protocol
2963 A long standing bug in the mips64 remote protocol where by GDB
2964 expected certain 32 bit registers (ex SR) to be transfered as 32
2965 instead of 64 bits has been fixed.
2967 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2968 added to provide backward compatibility with older versions of GDB.
2970 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2972 The command ``set remotebinarydownload'' command has been replaced by
2973 ``set remote X-packet''. Other commands in ``set remote'' family
2974 include ``set remote P-packet''.
2976 * Breakpoint commands accept ranges.
2978 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2979 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2980 ``tracepoint passcount'' also accepts a range of tracepoints.
2982 * ``apropos'' command added.
2984 The ``apropos'' command searches through command names and
2985 documentation strings, printing out matches, making it much easier to
2986 try to find a command that does what you are looking for.
2990 A new machine oriented interface (MI) has been added to GDB. This
2991 interface is designed for debug environments running GDB as a separate
2992 process. This is part of the long term libGDB project. See the
2993 "GDB/MI" chapter of the GDB manual for further information. It can be
2994 enabled by configuring with:
2996 .../configure --enable-gdbmi
2998 *** Changes in GDB-4.18:
3000 * New native configurations
3002 HP-UX 10.20 hppa*-*-hpux10.20
3003 HP-UX 11.x hppa*-*-hpux11.0*
3004 M68K GNU/Linux m68*-*-linux*
3008 Fujitsu FR30 fr30-*-elf*
3009 Intel StrongARM strongarm-*-*
3010 Mitsubishi D30V d30v-*-*
3012 * OBSOLETE configurations
3014 Gould PowerNode, NP1 np1-*-*, pn-*-*
3016 Configurations that have been declared obsolete will be commented out,
3017 but the code will be left in place. If there is no activity to revive
3018 these configurations before the next release of GDB, the sources will
3019 be permanently REMOVED.
3023 As a compatibility experiment, GDB's source files buildsym.h and
3024 buildsym.c have been converted to pure standard C, no longer
3025 containing any K&R compatibility code. We believe that all systems in
3026 use today either come with a standard C compiler, or have a GCC port
3027 available. If this is not true, please report the affected
3028 configuration to bug-gdb@gnu.org immediately. See the README file for
3029 information about getting a standard C compiler if you don't have one
3034 GDB now uses readline 2.2.
3036 * set extension-language
3038 You can now control the mapping between filename extensions and source
3039 languages by using the `set extension-language' command. For instance,
3040 you can ask GDB to treat .c files as C++ by saying
3041 set extension-language .c c++
3042 The command `info extensions' lists all of the recognized extensions
3043 and their associated languages.
3045 * Setting processor type for PowerPC and RS/6000
3047 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3048 you can use the `set processor' command to specify what variant of the
3049 PowerPC family you are debugging. The command
3053 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3054 following PowerPC and RS6000 variants:
3056 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3057 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3059 403GC IBM PowerPC 403GC
3060 505 Motorola PowerPC 505
3061 860 Motorola PowerPC 860 or 850
3062 601 Motorola PowerPC 601
3063 602 Motorola PowerPC 602
3064 603 Motorola/IBM PowerPC 603 or 603e
3065 604 Motorola PowerPC 604 or 604e
3066 750 Motorola/IBM PowerPC 750 or 750
3068 At the moment, this command just tells GDB what to name the
3069 special-purpose processor registers. Since almost all the affected
3070 registers are inaccessible to user-level programs, this command is
3071 only useful for remote debugging in its present form.
3075 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3076 more extensive support for HP-UX. Added features include shared
3077 library support, kernel threads and hardware watchpoints for 11.00,
3078 support for HP's ANSI C and C++ compilers, and a compatibility mode
3079 for xdb and dbx commands.
3083 HP's donation includes the new concept of catchpoints, which is a
3084 generalization of the old catch command. On HP-UX, it is now possible
3085 to catch exec, fork, and vfork, as well as library loading.
3087 This means that the existing catch command has changed; its first
3088 argument now specifies the type of catch to be set up. See the
3089 output of "help catch" for a list of catchpoint types.
3091 * Debugging across forks
3093 On HP-UX, you can choose which process to debug when a fork() happens
3098 HP has donated a curses-based terminal user interface (TUI). To get
3099 it, build with --enable-tui. Although this can be enabled for any
3100 configuration, at present it only works for native HP debugging.
3102 * GDB remote protocol additions
3104 A new protocol packet 'X' that writes binary data is now available.
3105 Default behavior is to try 'X', then drop back to 'M' if the stub
3106 fails to respond. The settable variable `remotebinarydownload'
3107 allows explicit control over the use of 'X'.
3109 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3110 full 64-bit address. The command
3112 set remoteaddresssize 32
3114 can be used to revert to the old behaviour. For existing remote stubs
3115 the change should not be noticed, as the additional address information
3118 In order to assist in debugging stubs, you may use the maintenance
3119 command `packet' to send any text string to the stub. For instance,
3121 maint packet heythere
3123 sends the packet "$heythere#<checksum>". Note that it is very easy to
3124 disrupt a debugging session by sending the wrong packet at the wrong
3127 The compare-sections command allows you to compare section data on the
3128 target to what is in the executable file without uploading or
3129 downloading, by comparing CRC checksums.
3131 * Tracing can collect general expressions
3133 You may now collect general expressions at tracepoints. This requires
3134 further additions to the target-side stub; see tracepoint.c and
3135 doc/agentexpr.texi for further details.
3137 * mask-address variable for Mips
3139 For Mips targets, you may control the zeroing of the upper 32 bits of
3140 a 64-bit address by entering `set mask-address on'. This is mainly
3141 of interest to users of embedded R4xxx and R5xxx processors.
3143 * Higher serial baud rates
3145 GDB's serial code now allows you to specify baud rates 57600, 115200,
3146 230400, and 460800 baud. (Note that your host system may not be able
3147 to achieve all of these rates.)
3151 The i960 configuration now includes an initial implementation of a
3152 builtin simulator, contributed by Jim Wilson.
3155 *** Changes in GDB-4.17:
3157 * New native configurations
3159 Alpha GNU/Linux alpha*-*-linux*
3160 Unixware 2.x i[3456]86-unixware2*
3161 Irix 6.x mips*-sgi-irix6*
3162 PowerPC GNU/Linux powerpc-*-linux*
3163 PowerPC Solaris powerpcle-*-solaris*
3164 Sparc GNU/Linux sparc-*-linux*
3165 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3169 Argonaut Risc Chip (ARC) arc-*-*
3170 Hitachi H8/300S h8300*-*-*
3171 Matsushita MN10200 w/simulator mn10200-*-*
3172 Matsushita MN10300 w/simulator mn10300-*-*
3173 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3174 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3175 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3176 Mitsubishi D10V w/simulator d10v-*-*
3177 Mitsubishi M32R/D w/simulator m32r-*-elf*
3178 Tsqware Sparclet sparclet-*-*
3179 NEC V850 w/simulator v850-*-*
3181 * New debugging protocols
3183 ARM with RDI protocol arm*-*-*
3184 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3185 DDB and LSI variants of PMON protocol mips*-*-*
3186 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3187 PowerPC with SDS protocol powerpc{,le}-*-eabi
3188 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3192 All configurations can now understand and use the DWARF 2 debugging
3193 format. The choice is automatic, if the symbol file contains DWARF 2
3198 GDB now includes basic Java language support. This support is
3199 only useful with Java compilers that produce native machine code.
3201 * solib-absolute-prefix and solib-search-path
3203 For SunOS and SVR4 shared libraries, you may now set the prefix for
3204 loading absolute shared library symbol files, and the search path for
3205 locating non-absolute shared library symbol files.
3207 * Live range splitting
3209 GDB can now effectively debug code for which GCC has performed live
3210 range splitting as part of its optimization. See gdb/doc/LRS for
3211 more details on the expected format of the stabs information.
3215 GDB's support for the GNU Hurd, including thread debugging, has been
3216 updated to work with current versions of the Hurd.
3220 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3221 instruction set. ARM GDB automatically detects when Thumb
3222 instructions are in use, and adjusts disassembly and backtracing
3227 GDB's MIPS target configurations now handle the MIP16 16-bit
3232 GDB now includes support for overlays; if an executable has been
3233 linked such that multiple sections are based at the same address, GDB
3234 will decide which section to use for symbolic info. You can choose to
3235 control the decision manually, using overlay commands, or implement
3236 additional target-side support and use "overlay load-target" to bring
3237 in the overlay mapping. Do "help overlay" for more detail.
3241 The command "info symbol <address>" displays information about
3242 the symbol at the specified address.
3246 The standard remote protocol now includes an extension that allows
3247 asynchronous collection and display of trace data. This requires
3248 extensive support in the target-side debugging stub. Tracing mode
3249 includes a new interaction mode in GDB and new commands: see the
3250 file tracepoint.c for more details.
3254 Configurations for embedded MIPS now include a simulator contributed
3255 by Cygnus Solutions. The simulator supports the instruction sets
3256 of most MIPS variants.
3260 Sparc configurations may now include the ERC32 simulator contributed
3261 by the European Space Agency. The simulator is not built into
3262 Sparc targets by default; configure with --enable-sim to include it.
3266 For target configurations that may include multiple variants of a
3267 basic architecture (such as MIPS and SH), you may now set the
3268 architecture explicitly. "set arch" sets, "info arch" lists
3269 the possible architectures.
3271 *** Changes in GDB-4.16:
3273 * New native configurations
3275 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3276 M68K NetBSD m68k-*-netbsd*
3277 PowerPC AIX 4.x powerpc-*-aix*
3278 PowerPC MacOS powerpc-*-macos*
3279 PowerPC Windows NT powerpcle-*-cygwin32
3280 RS/6000 AIX 4.x rs6000-*-aix4*
3284 ARM with RDP protocol arm-*-*
3285 I960 with MON960 i960-*-coff
3286 MIPS VxWorks mips*-*-vxworks*
3287 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3288 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3290 Matra Sparclet sparclet-*-*
3294 The powerpc-eabi configuration now includes the PSIM simulator,
3295 contributed by Andrew Cagney, with assistance from Mike Meissner.
3296 PSIM is a very elaborate model of the PowerPC, including not only
3297 basic instruction set execution, but also details of execution unit
3298 performance and I/O hardware. See sim/ppc/README for more details.
3302 GDB now works with Solaris 2.5.
3304 * Windows 95/NT native
3306 GDB will now work as a native debugger on Windows 95 and Windows NT.
3307 To build it from source, you must use the "gnu-win32" environment,
3308 which uses a DLL to emulate enough of Unix to run the GNU tools.
3309 Further information, binaries, and sources are available at
3310 ftp.cygnus.com, under pub/gnu-win32.
3312 * dont-repeat command
3314 If a user-defined command includes the command `dont-repeat', then the
3315 command will not be repeated if the user just types return. This is
3316 useful if the command is time-consuming to run, so that accidental
3317 extra keystrokes don't run the same command many times.
3319 * Send break instead of ^C
3321 The standard remote protocol now includes an option to send a break
3322 rather than a ^C to the target in order to interrupt it. By default,
3323 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3325 * Remote protocol timeout
3327 The standard remote protocol includes a new variable `remotetimeout'
3328 that allows you to set the number of seconds before GDB gives up trying
3329 to read from the target. The default value is 2.
3331 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3333 By default GDB will automatically keep track of objects as they are
3334 loaded and unloaded by the dynamic linker. By using the command `set
3335 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3336 when shared library events occur, thus allowing you to set breakpoints
3337 in shared libraries which are explicitly loaded by the inferior.
3339 Note this feature does not work on hpux8. On hpux9 you must link
3340 /usr/lib/end.o into your program. This feature should work
3341 automatically on hpux10.
3343 * Irix 5.x hardware watchpoint support
3345 Irix 5 configurations now support the use of hardware watchpoints.
3347 * Mips protocol "SYN garbage limit"
3349 When debugging a Mips target using the `target mips' protocol, you
3350 may set the number of characters that GDB will ignore by setting
3351 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3352 every character. The default value is 1050.
3354 * Recording and replaying remote debug sessions
3356 If you set `remotelogfile' to the name of a file, gdb will write to it
3357 a recording of a remote debug session. This recording may then be
3358 replayed back to gdb using "gdbreplay". See gdbserver/README for
3359 details. This is useful when you have a problem with GDB while doing
3360 remote debugging; you can make a recording of the session and send it
3361 to someone else, who can then recreate the problem.
3363 * Speedups for remote debugging
3365 GDB includes speedups for downloading and stepping MIPS systems using
3366 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3367 and more efficient S-record downloading.
3369 * Memory use reductions and statistics collection
3371 GDB now uses less memory and reports statistics about memory usage.
3372 Try the `maint print statistics' command, for example.
3374 *** Changes in GDB-4.15:
3376 * Psymtabs for XCOFF
3378 The symbol reader for AIX GDB now uses partial symbol tables. This
3379 can greatly improve startup time, especially for large executables.
3381 * Remote targets use caching
3383 Remote targets now use a data cache to speed up communication with the
3384 remote side. The data cache could lead to incorrect results because
3385 it doesn't know about volatile variables, thus making it impossible to
3386 debug targets which use memory mapped I/O devices. `set remotecache
3387 off' turns the the data cache off.
3389 * Remote targets may have threads
3391 The standard remote protocol now includes support for multiple threads
3392 in the target system, using new protocol commands 'H' and 'T'. See
3393 gdb/remote.c for details.
3397 If GDB is configured with `--enable-netrom', then it will include
3398 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3399 acts as though it is a bank of ROM on the target board, but you can
3400 write into it over the network. GDB's support consists only of
3401 support for fast loading into the emulated ROM; to debug, you must use
3402 another protocol, such as standard remote protocol. The usual
3403 sequence is something like
3405 target nrom <netrom-hostname>
3407 target remote <netrom-hostname>:1235
3411 GDB now includes support for the Apple Macintosh, as a host only. It
3412 may be run as either an MPW tool or as a standalone application, and
3413 it can debug through the serial port. All the usual GDB commands are
3414 available, but to the target command, you must supply "serial" as the
3415 device type instead of "/dev/ttyXX". See mpw-README in the main
3416 directory for more information on how to build. The MPW configuration
3417 scripts */mpw-config.in support only a few targets, and only the
3418 mips-idt-ecoff target has been tested.
3422 GDB configuration now uses autoconf. This is not user-visible,
3423 but does simplify configuration and building.
3427 GDB now supports hpux10.
3429 *** Changes in GDB-4.14:
3431 * New native configurations
3433 x86 FreeBSD i[345]86-*-freebsd
3434 x86 NetBSD i[345]86-*-netbsd
3435 NS32k NetBSD ns32k-*-netbsd
3436 Sparc NetBSD sparc-*-netbsd
3440 A29K VxWorks a29k-*-vxworks
3441 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3442 CPU32 EST-300 emulator m68*-*-est*
3443 PowerPC ELF powerpc-*-elf
3446 * Alpha OSF/1 support for procfs
3448 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3449 possible to attach to running processes. As the mounting of the /proc
3450 filesystem is optional on the Alpha, GDB automatically determines
3451 the availability of /proc during startup. This can lead to problems
3452 if /proc is unmounted after GDB has been started.
3454 * Arguments to user-defined commands
3456 User commands may accept up to 10 arguments separated by whitespace.
3457 Arguments are accessed within the user command via $arg0..$arg9. A
3460 print $arg0 + $arg1 + $arg2
3462 To execute the command use:
3465 Defines the command "adder" which prints the sum of its three arguments.
3466 Note the arguments are text substitutions, so they may reference variables,
3467 use complex expressions, or even perform inferior function calls.
3469 * New `if' and `while' commands
3471 This makes it possible to write more sophisticated user-defined
3472 commands. Both commands take a single argument, which is the
3473 expression to evaluate, and must be followed by the commands to
3474 execute, one per line, if the expression is nonzero, the list being
3475 terminated by the word `end'. The `if' command list may include an
3476 `else' word, which causes the following commands to be executed only
3477 if the expression is zero.
3479 * Fortran source language mode
3481 GDB now includes partial support for Fortran 77. It will recognize
3482 Fortran programs and can evaluate a subset of Fortran expressions, but
3483 variables and functions may not be handled correctly. GDB will work
3484 with G77, but does not yet know much about symbols emitted by other
3487 * Better HPUX support
3489 Most debugging facilities now work on dynamic executables for HPPAs
3490 running hpux9 or later. You can attach to running dynamically linked
3491 processes, but by default the dynamic libraries will be read-only, so
3492 for instance you won't be able to put breakpoints in them. To change
3493 that behavior do the following before running the program:
3499 This will cause the libraries to be mapped private and read-write.
3500 To revert to the normal behavior, do this:
3506 You cannot set breakpoints or examine data in the library until after
3507 the library is loaded if the function/data symbols do not have
3510 GDB can now also read debug symbols produced by the HP C compiler on
3511 HPPAs (sorry, no C++, Fortran or 68k support).
3513 * Target byte order now dynamically selectable
3515 You can choose which byte order to use with a target system, via the
3516 commands "set endian big" and "set endian little", and you can see the
3517 current setting by using "show endian". You can also give the command
3518 "set endian auto", in which case GDB will use the byte order
3519 associated with the executable. Currently, only embedded MIPS
3520 configurations support dynamic selection of target byte order.
3522 * New DOS host serial code
3524 This version uses DPMI interrupts to handle buffered I/O, so you
3525 no longer need to run asynctsr when debugging boards connected to
3528 *** Changes in GDB-4.13:
3530 * New "complete" command
3532 This lists all the possible completions for the rest of the line, if it
3533 were to be given as a command itself. This is intended for use by emacs.
3535 * Trailing space optional in prompt
3537 "set prompt" no longer adds a space for you after the prompt you set. This
3538 allows you to set a prompt which ends in a space or one that does not.
3540 * Breakpoint hit counts
3542 "info break" now displays a count of the number of times the breakpoint
3543 has been hit. This is especially useful in conjunction with "ignore"; you
3544 can ignore a large number of breakpoint hits, look at the breakpoint info
3545 to see how many times the breakpoint was hit, then run again, ignoring one
3546 less than that number, and this will get you quickly to the last hit of
3549 * Ability to stop printing at NULL character
3551 "set print null-stop" will cause GDB to stop printing the characters of
3552 an array when the first NULL is encountered. This is useful when large
3553 arrays actually contain only short strings.
3555 * Shared library breakpoints
3557 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3558 breakpoints in shared libraries before the executable is run.
3560 * Hardware watchpoints
3562 There is a new hardware breakpoint for the watch command for sparclite
3563 targets. See gdb/sparclite/hw_breakpoint.note.
3565 Hardware watchpoints are also now supported under GNU/Linux.
3569 Annotations have been added. These are for use with graphical interfaces,
3570 and are still experimental. Currently only gdba.el uses these.
3572 * Improved Irix 5 support
3574 GDB now works properly with Irix 5.2.
3576 * Improved HPPA support
3578 GDB now works properly with the latest GCC and GAS.
3580 * New native configurations
3582 Sequent PTX4 i[34]86-sequent-ptx4
3583 HPPA running OSF/1 hppa*-*-osf*
3584 Atari TT running SVR4 m68*-*-sysv4*
3585 RS/6000 LynxOS rs6000-*-lynxos*
3589 OS/9000 i[34]86-*-os9k
3590 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3593 * Hitachi SH7000 and E7000-PC ICE support
3595 There is now support for communicating with the Hitachi E7000-PC ICE.
3596 This is available automatically when GDB is configured for the SH.
3600 As usual, a variety of small fixes and improvements, both generic
3601 and configuration-specific. See the ChangeLog for more detail.
3603 *** Changes in GDB-4.12:
3605 * Irix 5 is now supported
3609 GDB-4.12 on the HPPA has a number of changes which make it unable
3610 to debug the output from the currently released versions of GCC and
3611 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3612 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3613 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3616 *** Changes in GDB-4.11:
3618 * User visible changes:
3622 The "set remotedebug" option is now consistent between the mips remote
3623 target, remote targets using the gdb-specific protocol, UDI (AMD's
3624 debug protocol for the 29k) and the 88k bug monitor. It is now an
3625 integer specifying a debug level (normally 0 or 1, but 2 means more
3626 debugging info for the mips target).
3628 * DEC Alpha native support
3630 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3631 debug info, but GDB works fairly well with the DEC compiler and should
3632 work with a future GCC release. See the README file for a few
3633 Alpha-specific notes.
3635 * Preliminary thread implementation
3637 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3639 * LynxOS native and target support for 386
3641 This release has been hosted on LynxOS 2.2, and also can be configured
3642 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3645 * Improvements in C++ mangling/demangling.
3647 This release has much better g++ debugging, specifically in name
3648 mangling/demangling, virtual function calls, print virtual table,
3649 call methods, ...etc.
3651 *** Changes in GDB-4.10:
3653 * User visible changes:
3655 Remote debugging using the GDB-specific (`target remote') protocol now
3656 supports the `load' command. This is only useful if you have some
3657 other way of getting the stub to the target system, and you can put it
3658 somewhere in memory where it won't get clobbered by the download.
3660 Filename completion now works.
3662 When run under emacs mode, the "info line" command now causes the
3663 arrow to point to the line specified. Also, "info line" prints
3664 addresses in symbolic form (as well as hex).
3666 All vxworks based targets now support a user settable option, called
3667 vxworks-timeout. This option represents the number of seconds gdb
3668 should wait for responses to rpc's. You might want to use this if
3669 your vxworks target is, perhaps, a slow software simulator or happens
3670 to be on the far side of a thin network line.
3674 This release contains support for using a DEC alpha as a GDB host for
3675 cross debugging. Native alpha debugging is not supported yet.
3678 *** Changes in GDB-4.9:
3682 This is the first GDB release which is accompanied by a matching testsuite.
3683 The testsuite requires installation of dejagnu, which should be available
3684 via ftp from most sites that carry GNU software.
3688 'Cfront' style demangling has had its name changed to 'ARM' style, to
3689 emphasize that it was written from the specifications in the C++ Annotated
3690 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3691 disclaimers, it still generated too much confusion with users attempting to
3692 use gdb with AT&T cfront.
3696 GDB now uses a standard remote interface to a simulator library.
3697 So far, the library contains simulators for the Zilog Z8001/2, the
3698 Hitachi H8/300, H8/500 and Super-H.
3700 * New targets supported
3702 H8/300 simulator h8300-hitachi-hms or h8300hms
3703 H8/500 simulator h8500-hitachi-hms or h8500hms
3704 SH simulator sh-hitachi-hms or sh
3705 Z8000 simulator z8k-zilog-none or z8ksim
3706 IDT MIPS board over serial line mips-idt-ecoff
3708 Cross-debugging to GO32 targets is supported. It requires a custom
3709 version of the i386-stub.c module which is integrated with the
3710 GO32 memory extender.
3712 * New remote protocols
3714 MIPS remote debugging protocol.
3716 * New source languages supported
3718 This version includes preliminary support for Chill, a Pascal like language
3719 used by telecommunications companies. Chill support is also being integrated
3720 into the GNU compiler, but we don't know when it will be publically available.
3723 *** Changes in GDB-4.8:
3725 * HP Precision Architecture supported
3727 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3728 version of this support was available as a set of patches from the
3729 University of Utah. GDB does not support debugging of programs
3730 compiled with the HP compiler, because HP will not document their file
3731 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3732 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3734 Many problems in the preliminary version have been fixed.
3736 * Faster and better demangling
3738 We have improved template demangling and fixed numerous bugs in the GNU style
3739 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3740 character types (wchar_t) are now supported. Demangling of each symbol is now
3741 only done once, and is cached when the symbol table for a file is read in.
3742 This results in a small increase in memory usage for C programs, a moderate
3743 increase in memory usage for C++ programs, and a fantastic speedup in
3746 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3747 from the specifications in the Annotated Reference Manual, which AT&T's
3748 compiler does not actually implement.
3750 * G++ multiple inheritance compiler problem
3752 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3753 inheritance lattices was reworked to properly discover ambiguities. We
3754 recently found an example which causes this new algorithm to fail in a
3755 very subtle way, producing bad debug information for those classes.
3756 The file 'gcc.patch' (in this directory) can be applied to gcc to
3757 circumvent the problem. A future GCC release will contain a complete
3760 The previous G++ debug info problem (mentioned below for the gdb-4.7
3761 release) is fixed in gcc version 2.3.2.
3763 * Improved configure script
3765 The `configure' script will now attempt to guess your system type if
3766 you don't supply a host system type. The old scheme of supplying a
3767 host system triplet is preferable over using this. All the magic is
3768 done in the new `config.guess' script. Examine it for details.
3770 We have also brought our configure script much more in line with the FSF's
3771 version. It now supports the --with-xxx options. In particular,
3772 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3773 The resulting GDB will not be able to read arbitrary object file formats --
3774 only the format ``expected'' to be used on the configured target system.
3775 We hope to make this the default in a future release.
3777 * Documentation improvements
3779 There's new internal documentation on how to modify GDB, and how to
3780 produce clean changes to the code. We implore people to read it
3781 before submitting changes.
3783 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3784 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3785 `info' files are also provided. To build `info' files from scratch,
3786 you will need the latest `makeinfo' release, which will be available in
3787 a future texinfo-X.Y release.
3789 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3790 We're not sure exactly which versions have this problem, but it has
3791 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3792 or better. If that isn't possible, there is a patch in
3793 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3794 around this problem.
3798 GDB now supports array constants that can be used in expressions typed in by
3799 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3800 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3803 The new directory `gdb/sparclite' contains a program that demonstrates
3804 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3806 * New native hosts supported
3808 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3809 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3811 * New targets supported
3813 AMD 29k family via UDI a29k-amd-udi or udi29k
3815 * New file formats supported
3817 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3818 HPUX core files, and SCO 3.2v2 core files.
3822 Attaching to processes now works again; thanks for the many bug reports.
3824 We have also stomped on a bunch of core dumps caused by
3825 printf_filtered("%s") problems.
3827 We eliminated a copyright problem on the rpc and ptrace header files
3828 for VxWorks, which was discovered at the last minute during the 4.7
3829 release. You should now be able to build a VxWorks GDB.
3831 You can now interrupt gdb while an attached process is running. This
3832 will cause the attached process to stop, and give control back to GDB.
3834 We fixed problems caused by using too many file descriptors
3835 for reading symbols from object files and libraries. This was
3836 especially a problem for programs that used many (~100) shared
3839 The `step' command now only enters a subroutine if there is line number
3840 information for the subroutine. Otherwise it acts like the `next'
3841 command. Previously, `step' would enter subroutines if there was
3842 any debugging information about the routine. This avoids problems
3843 when using `cc -g1' on MIPS machines.
3845 * Internal improvements
3847 GDB's internal interfaces have been improved to make it easier to support
3848 debugging of multiple languages in the future.
3850 GDB now uses a common structure for symbol information internally.
3851 Minimal symbols (derived from linkage symbols in object files), partial
3852 symbols (from a quick scan of debug information), and full symbols
3853 contain a common subset of information, making it easier to write
3854 shared code that handles any of them.
3856 * New command line options
3858 We now accept --silent as an alias for --quiet.
3862 The memory-mapped-malloc library is now licensed under the GNU Library
3863 General Public License.
3865 *** Changes in GDB-4.7:
3867 * Host/native/target split
3869 GDB has had some major internal surgery to untangle the support for
3870 hosts and remote targets. Now, when you configure GDB for a remote
3871 target, it will no longer load in all of the support for debugging
3872 local programs on the host. When fully completed and tested, this will
3873 ensure that arbitrary host/target combinations are possible.
3875 The primary conceptual shift is to separate the non-portable code in
3876 GDB into three categories. Host specific code is required any time GDB
3877 is compiled on that host, regardless of the target. Target specific
3878 code relates to the peculiarities of the target, but can be compiled on
3879 any host. Native specific code is everything else: it can only be
3880 built when the host and target are the same system. Child process
3881 handling and core file support are two common `native' examples.
3883 GDB's use of /proc for controlling Unix child processes is now cleaner.
3884 It has been split out into a single module under the `target_ops' vector,
3885 plus two native-dependent functions for each system that uses /proc.
3887 * New hosts supported
3889 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3890 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3891 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3893 * New targets supported
3895 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3896 68030 and CPU32 m68030-*-*, m68332-*-*
3898 * New native hosts supported
3900 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3901 (386bsd is not well tested yet)
3902 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3904 * New file formats supported
3906 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3907 supports reading of `a.out.adobe' object files, which are an a.out
3908 format extended with minimal information about multiple sections.
3912 `show copying' is the same as the old `info copying'.
3913 `show warranty' is the same as `info warrantee'.
3914 These were renamed for consistency. The old commands continue to work.
3916 `info handle' is a new alias for `info signals'.
3918 You can now define pre-command hooks, which attach arbitrary command
3919 scripts to any command. The commands in the hook will be executed
3920 prior to the user's command. You can also create a hook which will be
3921 executed whenever the program stops. See gdb.texinfo.
3925 We now deal with Cfront style name mangling, and can even extract type
3926 info from mangled symbols. GDB can automatically figure out which
3927 symbol mangling style your C++ compiler uses.
3929 Calling of methods and virtual functions has been improved as well.
3933 The crash that occured when debugging Sun Ansi-C compiled binaries is
3934 fixed. This was due to mishandling of the extra N_SO stabs output
3937 We also finally got Ultrix 4.2 running in house, and fixed core file
3938 support, with help from a dozen people on the net.
3940 John M. Farrell discovered that the reason that single-stepping was so
3941 slow on all of the Mips based platforms (primarily SGI and DEC) was
3942 that we were trying to demangle and lookup a symbol used for internal
3943 purposes on every instruction that was being stepped through. Changing
3944 the name of that symbol so that it couldn't be mistaken for a C++
3945 mangled symbol sped things up a great deal.
3947 Rich Pixley sped up symbol lookups in general by getting much smarter
3948 about when C++ symbol mangling is necessary. This should make symbol
3949 completion (TAB on the command line) much faster. It's not as fast as
3950 we'd like, but it's significantly faster than gdb-4.6.
3954 A new user controllable variable 'call_scratch_address' can
3955 specify the location of a scratch area to be used when GDB
3956 calls a function in the target. This is necessary because the
3957 usual method of putting the scratch area on the stack does not work
3958 in systems that have separate instruction and data spaces.
3960 We integrated changes to support the 29k UDI (Universal Debugger
3961 Interface), but discovered at the last minute that we didn't have all
3962 of the appropriate copyright paperwork. We are working with AMD to
3963 resolve this, and hope to have it available soon.
3967 We have sped up the remote serial line protocol, especially for targets
3968 with lots of registers. It now supports a new `expedited status' ('T')
3969 message which can be used in place of the existing 'S' status message.
3970 This allows the remote stub to send only the registers that GDB
3971 needs to make a quick decision about single-stepping or conditional
3972 breakpoints, eliminating the need to fetch the entire register set for
3973 each instruction being stepped through.
3975 The GDB remote serial protocol now implements a write-through cache for
3976 registers, only re-reading the registers if the target has run.
3978 There is also a new remote serial stub for SPARC processors. You can
3979 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3980 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3981 processor with a serial port.
3985 Configure.in files have become much easier to read and modify. A new
3986 `table driven' format makes it more obvious what configurations are
3987 supported, and what files each one uses.
3991 There is a new opcodes library which will eventually contain all of the
3992 disassembly routines and opcode tables. At present, it only contains
3993 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3994 disassembler (binutils/objdump) to share these routines.
3996 The libiberty library is now copylefted under the GNU Library General
3997 Public License. This allows more liberal use, and was done so libg++
3998 can use it. This makes no difference to GDB, since the Library License
3999 grants all the rights from the General Public License.
4003 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4004 reference to the stabs symbol info used by the debugger. It is (as far
4005 as we know) the only published document on this fascinating topic. We
4006 encourage you to read it, compare it to the stabs information on your
4007 system, and send improvements on the document in general (to
4008 bug-gdb@prep.ai.mit.edu).
4010 And, of course, many bugs have been fixed.
4013 *** Changes in GDB-4.6:
4015 * Better support for C++ function names
4017 GDB now accepts as input the "demangled form" of C++ overloaded function
4018 names and member function names, and can do command completion on such names
4019 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4020 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4021 Make use of command completion, it is your friend.
4023 GDB also now accepts a variety of C++ mangled symbol formats. They are
4024 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4025 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4026 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4027 for the list of formats.
4029 * G++ symbol mangling problem
4031 Recent versions of gcc have a bug in how they emit debugging information for
4032 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4033 directory) can be applied to gcc to fix the problem. Alternatively, if you
4034 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4035 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4036 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4039 * New 'maintenance' command
4041 All of the commands related to hacking GDB internals have been moved out of
4042 the main command set, and now live behind the 'maintenance' command. This
4043 can also be abbreviated as 'mt'. The following changes were made:
4045 dump-me -> maintenance dump-me
4046 info all-breakpoints -> maintenance info breakpoints
4047 printmsyms -> maintenance print msyms
4048 printobjfiles -> maintenance print objfiles
4049 printpsyms -> maintenance print psymbols
4050 printsyms -> maintenance print symbols
4052 The following commands are new:
4054 maintenance demangle Call internal GDB demangler routine to
4055 demangle a C++ link name and prints the result.
4056 maintenance print type Print a type chain for a given symbol
4058 * Change to .gdbinit file processing
4060 We now read the $HOME/.gdbinit file before processing the argv arguments
4061 (e.g. reading symbol files or core files). This allows global parameters to
4062 be set, which will apply during the symbol reading. The ./.gdbinit is still
4063 read after argv processing.
4065 * New hosts supported
4067 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4069 GNU/Linux support i386-unknown-linux or linux
4071 We are also including code to support the HP/PA running BSD and HPUX. This
4072 is almost guaranteed not to work, as we didn't have time to test or build it
4073 for this release. We are including it so that the more adventurous (or
4074 masochistic) of you can play with it. We also had major problems with the
4075 fact that the compiler that we got from HP doesn't support the -g option.
4078 * New targets supported
4080 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4082 * More smarts about finding #include files
4084 GDB now remembers the compilation directory for all include files, and for
4085 all files from which C is generated (like yacc and lex sources). This
4086 greatly improves GDB's ability to find yacc/lex sources, and include files,
4087 especially if you are debugging your program from a directory different from
4088 the one that contains your sources.
4090 We also fixed a bug which caused difficulty with listing and setting
4091 breakpoints in include files which contain C code. (In the past, you had to
4092 try twice in order to list an include file that you hadn't looked at before.)
4094 * Interesting infernals change
4096 GDB now deals with arbitrary numbers of sections, where the symbols for each
4097 section must be relocated relative to that section's landing place in the
4098 target's address space. This work was needed to support ELF with embedded
4099 stabs used by Solaris-2.0.
4101 * Bug fixes (of course!)
4103 There have been loads of fixes for the following things:
4104 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4105 i960, stabs, DOS(GO32), procfs, etc...
4107 See the ChangeLog for details.
4109 *** Changes in GDB-4.5:
4111 * New machines supported (host and target)
4113 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4115 SGI Irix-4.x mips-sgi-irix4 or iris4
4117 * New malloc package
4119 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4120 Mmalloc is capable of handling mutiple heaps of memory. It is also
4121 capable of saving a heap to a file, and then mapping it back in later.
4122 This can be used to greatly speedup the startup of GDB by using a
4123 pre-parsed symbol table which lives in a mmalloc managed heap. For
4124 more details, please read mmalloc/mmalloc.texi.
4128 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4129 'help info proc' for details.
4131 * MIPS ecoff symbol table format
4133 The code that reads MIPS symbol table format is now supported on all hosts.
4134 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4137 * File name changes for MS-DOS
4139 Many files in the config directories have been renamed to make it easier to
4140 support GDB on MS-DOSe systems (which have very restrictive file name
4141 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4142 environment) is close to working but has some remaining problems. Note
4143 that debugging of DOS programs is not supported, due to limitations
4144 in the ``operating system'', but it can be used to host cross-debugging.
4146 * Cross byte order fixes
4148 Many fixes have been made to support cross debugging of Sparc and MIPS
4149 targets from hosts whose byte order differs.
4151 * New -mapped and -readnow options
4153 If memory-mapped files are available on your system through the 'mmap'
4154 system call, you can use the -mapped option on the `file' or
4155 `symbol-file' commands to cause GDB to write the symbols from your
4156 program into a reusable file. If the program you are debugging is
4157 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4158 Future GDB debugging sessions will notice the presence of this file,
4159 and will quickly map in symbol information from it, rather than reading
4160 the symbol table from the executable program. Using the '-mapped'
4161 option in a GDB `file' or `symbol-file' command has the same effect as
4162 starting GDB with the '-mapped' command-line option.
4164 You can cause GDB to read the entire symbol table immediately by using
4165 the '-readnow' option with any of the commands that load symbol table
4166 information (or on the GDB command line). This makes the command
4167 slower, but makes future operations faster.
4169 The -mapped and -readnow options are typically combined in order to
4170 build a `fred.syms' file that contains complete symbol information.
4171 A simple GDB invocation to do nothing but build a `.syms' file for future
4174 gdb -batch -nx -mapped -readnow programname
4176 The `.syms' file is specific to the host machine on which GDB is run.
4177 It holds an exact image of GDB's internal symbol table. It cannot be
4178 shared across multiple host platforms.
4180 * longjmp() handling
4182 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4183 siglongjmp() without losing control. This feature has not yet been ported to
4184 all systems. It currently works on many 386 platforms, all MIPS-based
4185 platforms (SGI, DECstation, etc), and Sun3/4.
4189 Preliminary work has been put in to support the new Solaris OS from Sun. At
4190 this time, it can control and debug processes, but it is not capable of
4195 As always, many many bug fixes. The major areas were with g++, and mipsread.
4196 People using the MIPS-based platforms should experience fewer mysterious
4197 crashes and trashed symbol tables.
4199 *** Changes in GDB-4.4:
4201 * New machines supported (host and target)
4203 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4205 BSD Reno on Vax vax-dec-bsd
4206 Ultrix on Vax vax-dec-ultrix
4208 * New machines supported (target)
4210 AMD 29000 embedded, using EBMON a29k-none-none
4214 GDB continues to improve its handling of C++. `References' work better.
4215 The demangler has also been improved, and now deals with symbols mangled as
4216 per the Annotated C++ Reference Guide.
4218 GDB also now handles `stabs' symbol information embedded in MIPS
4219 `ecoff' symbol tables. Since the ecoff format was not easily
4220 extensible to handle new languages such as C++, this appeared to be a
4221 good way to put C++ debugging info into MIPS binaries. This option
4222 will be supported in the GNU C compiler, version 2, when it is
4225 * New features for SVR4
4227 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4228 shared libraries. Debugging dynamically linked programs should present
4229 only minor differences from debugging statically linked programs.
4231 The `info proc' command will print out information about any process
4232 on an SVR4 system (including the one you are debugging). At the moment,
4233 it prints the address mappings of the process.
4235 If you bring up GDB on another SVR4 system, please send mail to
4236 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4238 * Better dynamic linking support in SunOS
4240 Reading symbols from shared libraries which contain debugging symbols
4241 now works properly. However, there remain issues such as automatic
4242 skipping of `transfer vector' code during function calls, which
4243 make it harder to debug code in a shared library, than to debug the
4244 same code linked statically.
4248 GDB is now using the latest `getopt' routines from the FSF. This
4249 version accepts the -- prefix for options with long names. GDB will
4250 continue to accept the old forms (-option and +option) as well.
4251 Various single letter abbreviations for options have been explicity
4252 added to the option table so that they won't get overshadowed in the
4253 future by other options that begin with the same letter.
4257 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4258 Many assorted bugs have been handled. Many more remain to be handled.
4259 See the various ChangeLog files (primarily in gdb and bfd) for details.
4262 *** Changes in GDB-4.3:
4264 * New machines supported (host and target)
4266 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4267 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4268 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4270 * Almost SCO Unix support
4272 We had hoped to support:
4273 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4274 (except for core file support), but we discovered very late in the release
4275 that it has problems with process groups that render gdb unusable. Sorry
4276 about that. I encourage people to fix it and post the fixes.
4278 * Preliminary ELF and DWARF support
4280 GDB can read ELF object files on System V Release 4, and can handle
4281 debugging records for C, in DWARF format, in ELF files. This support
4282 is preliminary. If you bring up GDB on another SVR4 system, please
4283 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4288 GDB now uses the latest `readline' library. One user-visible change
4289 is that two tabs will list possible command completions, which previously
4290 required typing M-? (meta-question mark, or ESC ?).
4294 The `stepi' bug that many of you noticed has been squashed.
4295 Many bugs in C++ have been handled. Many more remain to be handled.
4296 See the various ChangeLog files (primarily in gdb and bfd) for details.
4298 * State of the MIPS world (in case you wondered):
4300 GDB can understand the symbol tables emitted by the compilers
4301 supplied by most vendors of MIPS-based machines, including DEC. These
4302 symbol tables are in a format that essentially nobody else uses.
4304 Some versions of gcc come with an assembler post-processor called
4305 mips-tfile. This program is required if you want to do source-level
4306 debugging of gcc-compiled programs. I believe FSF does not ship
4307 mips-tfile with gcc version 1, but it will eventually come with gcc
4310 Debugging of g++ output remains a problem. g++ version 1.xx does not
4311 really support it at all. (If you're lucky, you should be able to get
4312 line numbers and stack traces to work, but no parameters or local
4313 variables.) With some work it should be possible to improve the
4316 When gcc version 2 is released, you will have somewhat better luck.
4317 However, even then you will get confusing results for inheritance and
4320 We will eventually provide full debugging of g++ output on
4321 DECstations. This will probably involve some kind of stabs-in-ecoff
4322 encapulation, but the details have not been worked out yet.
4325 *** Changes in GDB-4.2:
4327 * Improved configuration
4329 Only one copy of `configure' exists now, and it is not self-modifying.
4330 Porting BFD is simpler.
4334 The `step' and `next' commands now only stop at the first instruction
4335 of a source line. This prevents the multiple stops that used to occur
4336 in switch statements, for-loops, etc. `Step' continues to stop if a
4337 function that has debugging information is called within the line.
4341 Lots of small bugs fixed. More remain.
4343 * New host supported (not target)
4345 Intel 386 PC clone running Mach i386-none-mach
4348 *** Changes in GDB-4.1:
4350 * Multiple source language support
4352 GDB now has internal scaffolding to handle several source languages.
4353 It determines the type of each source file from its filename extension,
4354 and will switch expression parsing and number formatting to match the
4355 language of the function in the currently selected stack frame.
4356 You can also specifically set the language to be used, with
4357 `set language c' or `set language modula-2'.
4361 GDB now has preliminary support for the GNU Modula-2 compiler,
4362 currently under development at the State University of New York at
4363 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4364 continue through the fall of 1991 and into 1992.
4366 Other Modula-2 compilers are currently not supported, and attempting to
4367 debug programs compiled with them will likely result in an error as the
4368 symbol table is read. Feel free to work on it, though!
4370 There are hooks in GDB for strict type checking and range checking,
4371 in the `Modula-2 philosophy', but they do not currently work.
4375 GDB can now write to executable and core files (e.g. patch
4376 a variable's value). You must turn this switch on, specify
4377 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4378 by assigning a new value to a variable. Modifications take
4381 * Automatic SunOS shared library reading
4383 When you run your program, GDB automatically determines where its
4384 shared libraries (if any) have been loaded, and reads their symbols.
4385 The `share' command is no longer needed. This also works when
4386 examining core files.
4390 You can specify the number of lines that the `list' command shows.
4393 * New machines supported (host and target)
4395 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4396 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4397 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4399 * New hosts supported (not targets)
4401 IBM RT/PC: romp-ibm-aix or rtpc
4403 * New targets supported (not hosts)
4405 AMD 29000 embedded with COFF a29k-none-coff
4406 AMD 29000 embedded with a.out a29k-none-aout
4407 Ultracomputer remote kernel debug a29k-nyu-kern
4409 * New remote interfaces
4415 *** Changes in GDB-4.0:
4419 Wide output is wrapped at good places to make the output more readable.
4421 Gdb now supports cross-debugging from a host machine of one type to a
4422 target machine of another type. Communication with the target system
4423 is over serial lines. The ``target'' command handles connecting to the
4424 remote system; the ``load'' command will download a program into the
4425 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4426 also supports debugging of realtime processes running under VxWorks,
4427 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4428 stub on the target system.
4430 New CPUs supported include the AMD 29000 and Intel 960.
4432 GDB now reads object files and symbol tables via a ``binary file''
4433 library, which allows a single copy of GDB to debug programs of multiple
4434 object file types such as a.out and coff.
4436 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4437 refcard.dvi and refcard.ps are available to format it).
4440 * Control-Variable user interface simplified
4442 All variables that control the operation of the debugger can be set
4443 by the ``set'' command, and displayed by the ``show'' command.
4445 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4446 ``Show prompt'' produces the response:
4447 Gdb's prompt is new-gdb=>.
4449 What follows are the NEW set commands. The command ``help set'' will
4450 print a complete list of old and new set commands. ``help set FOO''
4451 will give a longer description of the variable FOO. ``show'' will show
4452 all of the variable descriptions and their current settings.
4454 confirm on/off: Enables warning questions for operations that are
4455 hard to recover from, e.g. rerunning the program while
4456 it is already running. Default is ON.
4458 editing on/off: Enables EMACS style command line editing
4459 of input. Previous lines can be recalled with
4460 control-P, the current line can be edited with control-B,
4461 you can search for commands with control-R, etc.
4464 history filename NAME: NAME is where the gdb command history
4465 will be stored. The default is .gdb_history,
4466 or the value of the environment variable
4469 history size N: The size, in commands, of the command history. The
4470 default is 256, or the value of the environment variable
4473 history save on/off: If this value is set to ON, the history file will
4474 be saved after exiting gdb. If set to OFF, the
4475 file will not be saved. The default is OFF.
4477 history expansion on/off: If this value is set to ON, then csh-like
4478 history expansion will be performed on
4479 command line input. The default is OFF.
4481 radix N: Sets the default radix for input and output. It can be set
4482 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4483 in the current radix, so "set radix 10" is always a no-op.
4485 height N: This integer value is the number of lines on a page. Default
4486 is 24, the current `stty rows'' setting, or the ``li#''
4487 setting from the termcap entry matching the environment
4490 width N: This integer value is the number of characters on a line.
4491 Default is 80, the current `stty cols'' setting, or the ``co#''
4492 setting from the termcap entry matching the environment
4495 Note: ``set screensize'' is obsolete. Use ``set height'' and
4496 ``set width'' instead.
4498 print address on/off: Print memory addresses in various command displays,
4499 such as stack traces and structure values. Gdb looks
4500 more ``symbolic'' if you turn this off; it looks more
4501 ``machine level'' with it on. Default is ON.
4503 print array on/off: Prettyprint arrays. New convenient format! Default
4506 print demangle on/off: Print C++ symbols in "source" form if on,
4509 print asm-demangle on/off: Same, for assembler level printouts
4512 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4515 * Support for Epoch Environment.
4517 The epoch environment is a version of Emacs v18 with windowing. One
4518 new command, ``inspect'', is identical to ``print'', except that if you
4519 are running in the epoch environment, the value is printed in its own
4523 * Support for Shared Libraries
4525 GDB can now debug programs and core files that use SunOS shared libraries.
4526 Symbols from a shared library cannot be referenced
4527 before the shared library has been linked with the program (this
4528 happens after you type ``run'' and before the function main() is entered).
4529 At any time after this linking (including when examining core files
4530 from dynamically linked programs), gdb reads the symbols from each
4531 shared library when you type the ``sharedlibrary'' command.
4532 It can be abbreviated ``share''.
4534 sharedlibrary REGEXP: Load shared object library symbols for files
4535 matching a unix regular expression. No argument
4536 indicates to load symbols for all shared libraries.
4538 info sharedlibrary: Status of loaded shared libraries.
4543 A watchpoint stops execution of a program whenever the value of an
4544 expression changes. Checking for this slows down execution
4545 tremendously whenever you are in the scope of the expression, but is
4546 quite useful for catching tough ``bit-spreader'' or pointer misuse
4547 problems. Some machines such as the 386 have hardware for doing this
4548 more quickly, and future versions of gdb will use this hardware.
4550 watch EXP: Set a watchpoint (breakpoint) for an expression.
4552 info watchpoints: Information about your watchpoints.
4554 delete N: Deletes watchpoint number N (same as breakpoints).
4555 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4556 enable N: Re-enables watchpoint number N (same as breakpoints).
4559 * C++ multiple inheritance
4561 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4564 * C++ exception handling
4566 Gdb now supports limited C++ exception handling. Besides the existing
4567 ability to breakpoint on an exception handler, gdb can breakpoint on
4568 the raising of an exception (before the stack is peeled back to the
4571 catch FOO: If there is a FOO exception handler in the dynamic scope,
4572 set a breakpoint to catch exceptions which may be raised there.
4573 Multiple exceptions (``catch foo bar baz'') may be caught.
4575 info catch: Lists all exceptions which may be caught in the
4576 current stack frame.
4579 * Minor command changes
4581 The command ``call func (arg, arg, ...)'' now acts like the print
4582 command, except it does not print or save a value if the function's result
4583 is void. This is similar to dbx usage.
4585 The ``up'' and ``down'' commands now always print the frame they end up
4586 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4587 frames without printing.
4589 * New directory command
4591 'dir' now adds directories to the FRONT of the source search path.
4592 The path starts off empty. Source files that contain debug information
4593 about the directory in which they were compiled can be found even
4594 with an empty path; Sun CC and GCC include this information. If GDB can't
4595 find your source file in the current directory, type "dir .".
4597 * Configuring GDB for compilation
4599 For normal use, type ``./configure host''. See README or gdb.texinfo
4602 GDB now handles cross debugging. If you are remotely debugging between
4603 two different machines, type ``./configure host -target=targ''.
4604 Host is the machine where GDB will run; targ is the machine
4605 where the program that you are debugging will run.