1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.3.1
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 register_pretty_printer function in module gdb.printing now takes
19 an optional `replace' argument. If True the new printer replaces any
22 ** The "maint set python print-stack on|off" command has been
23 deprecated, and a new command: "set python print-stack on|off" has
24 replaced it. Additionally, the default for "print-stack" is now
27 ** A prompt subsitution hook (prompt_hook) is now available to the
30 ** A new command set/show extended-prompt has been added.
32 ** A new Python module, gdb.prompt has been added to the GDB Python
33 modules library. This module provides functionality for
34 escape sequentions in prompts (used by set/show
35 extended-prompt). These escape sequences are replaced by their
38 ** Python commands and convenience-functions located in
39 'data-directory'/python/gdb/command and
40 'data-directory'/python/gdb/function are now automatically loaded
43 ** Symbols now provide the "type" attribute, the type of the symbol.
45 ** The "gdb.breakpoint" function has been deprecated in favor of
48 ** Type objects for struct and union types now allow access to
49 the fields using standard Python dictionary (mapping) methods.
50 For example, "some_type['myfield']" now works, as does
53 ** A new event "gdb.new_objfile" has been added, triggered by loading a
56 * libthread-db-search-path now supports two special values: $sdir and $pdir.
57 $sdir specifies the default system locations of shared libraries.
58 $pdir specifies the directory where the libpthread used by the application
61 GDB no longer looks in $sdir and $pdir after it has searched the directories
62 mentioned in libthread-db-search-path. If you want to search those
63 directories, they must be specified in libthread-db-search-path.
64 The default value of libthread-db-search-path on GNU/Linux and Solaris
65 systems is now "$sdir:$pdir".
67 $pdir is not supported by gdbserver, it is currently ignored.
68 $sdir is supported by gdbserver.
70 * New configure option --with-iconv-bin.
71 When using the internationalization support like the one in the GNU C
72 library, GDB will invoke the "iconv" program to get a list of supported
73 character sets. If this program lives in a non-standard location, one can
74 use this option to specify where to find it.
76 * When natively debugging programs on PowerPC BookE processors running
77 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
78 watchpoints, which specify a mask in addition to an address to watch.
79 The mask specifies that some bits of an address (the bits which are
80 reset in the mask) should be ignored when matching the address accessed
81 by the inferior against the watchpoint address. See the "PowerPC Embedded"
82 section in the user manual for more details.
84 * The new option --once causes GDBserver to stop listening for connections once
85 the first connection is made. The listening port used by GDBserver will
86 become available after that.
88 * New commands "info macros", "info definitions",
89 and "alias" have been added.
91 * New function parameters suffix @entry specifies value of function parameter
92 at the time the function got called. Entry values are available only since
97 watch EXPRESSION mask MASK_VALUE
98 The watch command now supports the mask argument which allows creation
99 of masked watchpoints, if the current architecture supports this feature.
101 info auto-load-scripts [REGEXP]
102 This command was formerly named "maintenance print section-scripts".
103 It is now generally useful and is no longer a maintenance-only command.
105 * Tracepoints can now be enabled and disabled at any time after a trace
106 experiment has been started using the standard "enable" and "disable"
107 commands. It is now possible to start a trace experiment with no enabled
108 tracepoints; GDB will display a warning, but will allow the experiment to
109 begin, assuming that tracepoints will be enabled as needed while the trace
114 set print entry-values (both|compact|default|if-needed|no|only|preferred)
115 show print entry-values
116 Set printing of frame argument values at function entry. In some cases
117 GDB can determine the value of function argument which was passed by the
118 function caller, even if the value was modified inside the called function.
120 set debug entry-values
121 show debug entry-values
122 Control display of debugging info for determining frame argument values at
123 function entry and virtual tail call frames.
129 Dynamically enable a tracepoint in a started trace experiment.
133 Dynamically disable a tracepoint in a started trace experiment.
135 * Dcache size (number of lines) and line-size are now runtime-configurable
136 via "set dcache line" and "set dcache line-size" commands.
140 Texas Instruments TMS320C6x tic6x-*-*
142 *** Changes in GDB 7.3.1
144 * The build failure for NetBSD and OpenBSD targets have now been fixed.
146 *** Changes in GDB 7.3
148 * GDB has a new command: "thread find [REGEXP]".
149 It finds the thread id whose name, target id, or thread extra info
150 matches the given regular expression.
152 * The "catch syscall" command now works on mips*-linux* targets.
154 * The -data-disassemble MI command now supports modes 2 and 3 for
155 dumping the instruction opcodes.
157 * New command line options
159 -data-directory DIR Specify DIR as the "data-directory".
160 This is mostly for testing purposes.
162 * The "maint set python auto-load on|off" command has been renamed to
163 "set auto-load-scripts on|off".
165 * GDB has a new command: "set directories".
166 It is like the "dir" command except that it replaces the
167 source path list instead of augmenting it.
169 * GDB now understands thread names.
171 On GNU/Linux, "info threads" will display the thread name as set by
172 prctl or pthread_setname_np.
174 There is also a new command, "thread name", which can be used to
175 assign a name internally for GDB to display.
178 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
179 has been integrated into GDB.
183 ** The function gdb.Write now accepts an optional keyword 'stream'.
184 This keyword, when provided, will direct the output to either
185 stdout, stderr, or GDB's logging output.
187 ** Parameters can now be be sub-classed in Python, and in particular
188 you may implement the get_set_doc and get_show_doc functions.
189 This improves how Parameter set/show documentation is processed
190 and allows for more dynamic content.
192 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
193 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
194 have an is_valid method.
196 ** Breakpoints can now be sub-classed in Python, and in particular
197 you may implement a 'stop' function that is executed each time
198 the inferior reaches that breakpoint.
200 ** New function gdb.lookup_global_symbol looks up a global symbol.
202 ** GDB values in Python are now callable if the value represents a
203 function. For example, if 'some_value' represents a function that
204 takes two integer parameters and returns a value, you can call
205 that function like so:
207 result = some_value (10,20)
209 ** Module gdb.types has been added.
210 It contains a collection of utilities for working with gdb.Types objects:
211 get_basic_type, has_field, make_enum_dict.
213 ** Module gdb.printing has been added.
214 It contains utilities for writing and registering pretty-printers.
215 New classes: PrettyPrinter, SubPrettyPrinter,
216 RegexpCollectionPrettyPrinter.
217 New function: register_pretty_printer.
219 ** New commands "info pretty-printers", "enable pretty-printer" and
220 "disable pretty-printer" have been added.
222 ** gdb.parameter("directories") is now available.
224 ** New function gdb.newest_frame returns the newest frame in the
227 ** The gdb.InferiorThread class has a new "name" attribute. This
228 holds the thread's name.
230 ** Python Support for Inferior events.
231 Python scripts can add observers to be notified of events
232 occurring in the process being debugged.
233 The following events are currently supported:
234 - gdb.events.cont Continue event.
235 - gdb.events.exited Inferior exited event.
236 - gdb.events.stop Signal received, and Breakpoint hit events.
240 ** GDB now puts template parameters in scope when debugging in an
241 instantiation. For example, if you have:
243 template<int X> int func (void) { return X; }
245 then if you step into func<5>, "print X" will show "5". This
246 feature requires proper debuginfo support from the compiler; it
247 was added to GCC 4.5.
249 ** The motion commands "next", "finish", "until", and "advance" now
250 work better when exceptions are thrown. In particular, GDB will
251 no longer lose control of the inferior; instead, the GDB will
252 stop the inferior at the point at which the exception is caught.
253 This functionality requires a change in the exception handling
254 code that was introduced in GCC 4.5.
256 * GDB now follows GCC's rules on accessing volatile objects when
257 reading or writing target state during expression evaluation.
258 One notable difference to prior behavior is that "print x = 0"
259 no longer generates a read of x; the value of the assignment is
260 now always taken directly from the value being assigned.
262 * GDB now has some support for using labels in the program's source in
263 linespecs. For instance, you can use "advance label" to continue
264 execution to a label.
266 * GDB now has support for reading and writing a new .gdb_index
267 section. This section holds a fast index of DWARF debugging
268 information and can be used to greatly speed up GDB startup and
269 operation. See the documentation for `save gdb-index' for details.
271 * The "watch" command now accepts an optional "-location" argument.
272 When used, this causes GDB to watch the memory referred to by the
273 expression. Such a watchpoint is never deleted due to it going out
276 * GDB now supports thread debugging of core dumps on GNU/Linux.
278 GDB now activates thread debugging using the libthread_db library
279 when debugging GNU/Linux core dumps, similarly to when debugging
280 live processes. As a result, when debugging a core dump file, GDB
281 is now able to display pthread_t ids of threads. For example, "info
282 threads" shows the same output as when debugging the process when it
283 was live. In earlier releases, you'd see something like this:
286 * 1 LWP 6780 main () at main.c:10
288 While now you see this:
291 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
293 It is also now possible to inspect TLS variables when debugging core
296 When debugging a core dump generated on a machine other than the one
297 used to run GDB, you may need to point GDB at the correct
298 libthread_db library with the "set libthread-db-search-path"
299 command. See the user manual for more details on this command.
301 * When natively debugging programs on PowerPC BookE processors running
302 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
303 which stop execution of the inferior whenever it executes an instruction
304 at any address within the specified range. See the "PowerPC Embedded"
305 section in the user manual for more details.
307 * New features in the GDB remote stub, GDBserver
309 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
310 and i686 LynxOS (version 5.x).
312 ** GDBserver is now supported on Blackfin Linux.
314 * New native configurations
316 ia64 HP-UX ia64-*-hpux*
320 Analog Devices, Inc. Blackfin Processor bfin-*
322 * Ada task switching is now supported on sparc-elf targets when
323 debugging a program using the Ravenscar Profile. For more information,
324 see the "Tasking Support when using the Ravenscar Profile" section
325 in the GDB user manual.
327 * Guile support was removed.
329 * New features in the GNU simulator
331 ** The --map-info flag lists all known core mappings.
333 ** CFI flashes may be simulated via the "cfi" device.
335 *** Changes in GDB 7.2
337 * Shared library support for remote targets by default
339 When GDB is configured for a generic, non-OS specific target, like
340 for example, --target=arm-eabi or one of the many *-*-elf targets,
341 GDB now queries remote stubs for loaded shared libraries using the
342 `qXfer:libraries:read' packet. Previously, shared library support
343 was always disabled for such configurations.
347 ** Argument Dependent Lookup (ADL)
349 In C++ ADL lookup directs function search to the namespaces of its
350 arguments even if the namespace has not been imported.
360 Here the compiler will search for `foo' in the namespace of 'b'
361 and find A::foo. GDB now supports this. This construct is commonly
362 used in the Standard Template Library for operators.
364 ** Improved User Defined Operator Support
366 In addition to member operators, GDB now supports lookup of operators
367 defined in a namespace and imported with a `using' directive, operators
368 defined in the global scope, operators imported implicitly from an
369 anonymous namespace, and the ADL operators mentioned in the previous
371 GDB now also supports proper overload resolution for all the previously
372 mentioned flavors of operators.
374 ** static const class members
376 Printing of static const class members that are initialized in the
377 class definition has been fixed.
379 * Windows Thread Information Block access.
381 On Windows targets, GDB now supports displaying the Windows Thread
382 Information Block (TIB) structure. This structure is visible either
383 by using the new command `info w32 thread-information-block' or, by
384 dereferencing the new convenience variable named `$_tlb', a
385 thread-specific pointer to the TIB. This feature is also supported
386 when remote debugging using GDBserver.
390 Static tracepoints are calls in the user program into a tracing
391 library. One such library is a port of the LTTng kernel tracer to
392 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
393 When debugging with GDBserver, GDB now supports combining the GDB
394 tracepoint machinery with such libraries. For example: the user can
395 use GDB to probe a static tracepoint marker (a call from the user
396 program into the tracing library) with the new "strace" command (see
397 "New commands" below). This creates a "static tracepoint" in the
398 breakpoint list, that can be manipulated with the same feature set
399 as fast and regular tracepoints. E.g., collect registers, local and
400 global variables, collect trace state variables, and define
401 tracepoint conditions. In addition, the user can collect extra
402 static tracepoint marker specific data, by collecting the new
403 $_sdata internal variable. When analyzing the trace buffer, you can
404 inspect $_sdata like any other variable available to GDB. For more
405 information, see the "Tracepoints" chapter in GDB user manual. New
406 remote packets have been defined to support static tracepoints, see
407 the "New remote packets" section below.
409 * Better reconstruction of tracepoints after disconnected tracing
411 GDB will attempt to download the original source form of tracepoint
412 definitions when starting a trace run, and then will upload these
413 upon reconnection to the target, resulting in a more accurate
414 reconstruction of the tracepoints that are in use on the target.
418 You can now exercise direct control over the ways that GDB can
419 affect your program. For instance, you can disallow the setting of
420 breakpoints, so that the program can run continuously (assuming
421 non-stop mode). In addition, the "observer" variable is available
422 to switch all of the different controls; in observer mode, GDB
423 cannot affect the target's behavior at all, which is useful for
424 tasks like diagnosing live systems in the field.
426 * The new convenience variable $_thread holds the number of the
433 Return the address of the Windows Thread Information Block of a given thread.
437 In response to several of the tracepoint packets, the target may now
438 also respond with a number of intermediate `qRelocInsn' request
439 packets before the final result packet, to have GDB handle
440 relocating an instruction to execute at a different address. This
441 is particularly useful for stubs that support fast tracepoints. GDB
442 reports support for this feature in the qSupported packet.
446 List static tracepoint markers in the target program.
450 List static tracepoint markers at a given address in the target
453 qXfer:statictrace:read
455 Read the static trace data collected (by a `collect $_sdata'
456 tracepoint action). The remote stub reports support for this packet
457 to gdb's qSupported query.
461 Send the current settings of GDB's permission flags.
465 Send part of the source (textual) form of a tracepoint definition,
466 which includes location, conditional, and action list.
468 * The source command now accepts a -s option to force searching for the
469 script in the source search path even if the script name specifies
472 * New features in the GDB remote stub, GDBserver
474 - GDBserver now support tracepoints (including fast tracepoints, and
475 static tracepoints). The feature is currently supported by the
476 i386-linux and amd64-linux builds. See the "Tracepoints support
477 in gdbserver" section in the manual for more information.
479 GDBserver JIT compiles the tracepoint's conditional agent
480 expression bytecode into native code whenever possible for low
481 overhead dynamic tracepoints conditionals. For such tracepoints,
482 an expression that examines program state is evaluated when the
483 tracepoint is reached, in order to determine whether to capture
484 trace data. If the condition is simple and false, processing the
485 tracepoint finishes very quickly and no data is gathered.
487 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
488 for static tracepoints support.
490 - GDBserver now supports x86_64 Windows 64-bit debugging.
492 * GDB now sends xmlRegisters= in qSupported packet to indicate that
493 it understands register description.
495 * The --batch flag now disables pagination and queries.
497 * X86 general purpose registers
499 GDB now supports reading/writing byte, word and double-word x86
500 general purpose registers directly. This means you can use, say,
501 $ah or $ax to refer, respectively, to the byte register AH and
502 16-bit word register AX that are actually portions of the 32-bit
503 register EAX or 64-bit register RAX.
505 * The `commands' command now accepts a range of breakpoints to modify.
506 A plain `commands' following a command that creates multiple
507 breakpoints affects all the breakpoints set by that command. This
508 applies to breakpoints set by `rbreak', and also applies when a
509 single `break' command creates multiple breakpoints (e.g.,
510 breakpoints on overloaded c++ functions).
512 * The `rbreak' command now accepts a filename specification as part of
513 its argument, limiting the functions selected by the regex to those
514 in the specified file.
516 * Support for remote debugging Windows and SymbianOS shared libraries
517 from Unix hosts has been improved. Non Windows GDB builds now can
518 understand target reported file names that follow MS-DOS based file
519 system semantics, such as file names that include drive letters and
520 use the backslash character as directory separator. This makes it
521 possible to transparently use the "set sysroot" and "set
522 solib-search-path" on Unix hosts to point as host copies of the
523 target's shared libraries. See the new command "set
524 target-file-system-kind" described below, and the "Commands to
525 specify files" section in the user manual for more information.
529 eval template, expressions...
530 Convert the values of one or more expressions under the control
531 of the string template to a command line, and call it.
533 set target-file-system-kind unix|dos-based|auto
534 show target-file-system-kind
535 Set or show the assumed file system kind for target reported file
538 save breakpoints <filename>
539 Save all current breakpoint definitions to a file suitable for use
540 in a later debugging session. To read the saved breakpoint
541 definitions, use the `source' command.
543 `save tracepoints' is a new alias for `save-tracepoints'. The latter
546 info static-tracepoint-markers
547 Display information about static tracepoint markers in the target.
549 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
550 Define a static tracepoint by probing a marker at the given
551 function, line, address, or marker ID.
555 Enable and disable observer mode.
557 set may-write-registers on|off
558 set may-write-memory on|off
559 set may-insert-breakpoints on|off
560 set may-insert-tracepoints on|off
561 set may-insert-fast-tracepoints on|off
562 set may-interrupt on|off
563 Set individual permissions for GDB effects on the target. Note that
564 some of these settings can have undesirable or surprising
565 consequences, particularly when changed in the middle of a session.
566 For instance, disabling the writing of memory can prevent
567 breakpoints from being inserted, cause single-stepping to fail, or
568 even crash your program, if you disable after breakpoints have been
569 inserted. However, GDB should not crash.
571 set record memory-query on|off
572 show record memory-query
573 Control whether to stop the inferior if memory changes caused
574 by an instruction cannot be recorded.
579 The disassemble command now supports "start,+length" form of two arguments.
583 ** GDB now provides a new directory location, called the python directory,
584 where Python scripts written for GDB can be installed. The location
585 of that directory is <data-directory>/python, where <data-directory>
586 is the GDB data directory. For more details, see section `Scripting
587 GDB using Python' in the manual.
589 ** The GDB Python API now has access to breakpoints, symbols, symbol
590 tables, program spaces, inferiors, threads and frame's code blocks.
591 Additionally, GDB Parameters can now be created from the API, and
592 manipulated via set/show in the CLI.
594 ** New functions gdb.target_charset, gdb.target_wide_charset,
595 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
597 ** New exception gdb.GdbError.
599 ** Pretty-printers are now also looked up in the current program space.
601 ** Pretty-printers can now be individually enabled and disabled.
603 ** GDB now looks for names of Python scripts to auto-load in a
604 special section named `.debug_gdb_scripts', in addition to looking
605 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
607 * Tracepoint actions were unified with breakpoint commands. In particular,
608 there are no longer differences in "info break" output for breakpoints and
609 tracepoints and the "commands" command can be used for both tracepoints and
614 ARM Symbian arm*-*-symbianelf*
616 * D language support.
617 GDB now supports debugging programs written in the D programming
620 * GDB now supports the extended ptrace interface for PowerPC which is
621 available since Linux kernel version 2.6.34. This automatically enables
622 any hardware breakpoints and additional hardware watchpoints available in
623 the processor. The old ptrace interface exposes just one hardware
624 watchpoint and no hardware breakpoints.
626 * GDB is now able to use the Data Value Compare (DVC) register available on
627 embedded PowerPC processors to implement in hardware simple watchpoint
628 conditions of the form:
630 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
632 This works in native GDB running on Linux kernels with the extended ptrace
633 interface mentioned above.
635 *** Changes in GDB 7.1
641 GDB now supports importing of namespaces in C++. This enables the
642 user to inspect variables from imported namespaces. Support for
643 namepace aliasing has also been added. So, if a namespace is
644 aliased in the current scope (e.g. namepace C=A; ) the user can
645 print variables using the alias (e.g. (gdb) print C::x).
649 All known bugs relating to the printing of virtual base class were
650 fixed. It is now possible to call overloaded static methods using a
655 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
656 and reinterpret_cast<> are now handled by the C++ expression parser.
660 Xilinx MicroBlaze microblaze-*-*
665 Xilinx MicroBlaze microblaze
668 * Multi-program debugging.
670 GDB now has support for multi-program (a.k.a. multi-executable or
671 multi-exec) debugging. This allows for debugging multiple inferiors
672 simultaneously each running a different program under the same GDB
673 session. See "Debugging Multiple Inferiors and Programs" in the
674 manual for more information. This implied some user visible changes
675 in the multi-inferior support. For example, "info inferiors" now
676 lists inferiors that are not running yet or that have exited
677 already. See also "New commands" and "New options" below.
679 * New tracing features
681 GDB's tracepoint facility now includes several new features:
683 ** Trace state variables
685 GDB tracepoints now include support for trace state variables, which
686 are variables managed by the target agent during a tracing
687 experiment. They are useful for tracepoints that trigger each
688 other, so for instance one tracepoint can count hits in a variable,
689 and then a second tracepoint has a condition that is true when the
690 count reaches a particular value. Trace state variables share the
691 $-syntax of GDB convenience variables, and can appear in both
692 tracepoint actions and condition expressions. Use the "tvariable"
693 command to create, and "info tvariables" to view; see "Trace State
694 Variables" in the manual for more detail.
698 GDB now includes an option for defining fast tracepoints, which
699 targets may implement more efficiently, such as by installing a jump
700 into the target agent rather than a trap instruction. The resulting
701 speedup can be by two orders of magnitude or more, although the
702 tradeoff is that some program locations on some target architectures
703 might not allow fast tracepoint installation, for instance if the
704 instruction to be replaced is shorter than the jump. To request a
705 fast tracepoint, use the "ftrace" command, with syntax identical to
706 the regular trace command.
708 ** Disconnected tracing
710 It is now possible to detach GDB from the target while it is running
711 a trace experiment, then reconnect later to see how the experiment
712 is going. In addition, a new variable disconnected-tracing lets you
713 tell the target agent whether to continue running a trace if the
714 connection is lost unexpectedly.
718 GDB now has the ability to save the trace buffer into a file, and
719 then use that file as a target, similarly to you can do with
720 corefiles. You can select trace frames, print data that was
721 collected in them, and use tstatus to display the state of the
722 tracing run at the moment that it was saved. To create a trace
723 file, use "tsave <filename>", and to use it, do "target tfile
726 ** Circular trace buffer
728 You can ask the target agent to handle the trace buffer as a
729 circular buffer, discarding the oldest trace frames to make room for
730 newer ones, by setting circular-trace-buffer to on. This feature may
731 not be available for all target agents.
736 The disassemble command, when invoked with two arguments, now requires
737 the arguments to be comma-separated.
740 The info variables command now displays variable definitions. Files
741 which only declare a variable are not shown.
744 The source command is now capable of sourcing Python scripts.
745 This feature is dependent on the debugger being build with Python
748 Related to this enhancement is also the introduction of a new command
749 "set script-extension" (see below).
751 * New commands (for set/show, see "New options" below)
753 record save [<FILENAME>]
754 Save a file (in core file format) containing the process record
755 execution log for replay debugging at a later time.
757 record restore <FILENAME>
758 Restore the process record execution log that was saved at an
759 earlier time, for replay debugging.
761 add-inferior [-copies <N>] [-exec <FILENAME>]
764 clone-inferior [-copies <N>] [ID]
765 Make a new inferior ready to execute the same program another
771 maint info program-spaces
772 List the program spaces loaded into GDB.
774 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
775 show remote interrupt-sequence
776 Allow the user to select one of ^C, a BREAK signal or BREAK-g
777 as the sequence to the remote target in order to interrupt the execution.
778 Ctrl-C is a default. Some system prefers BREAK which is high level of
779 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
780 Magic SysRq g. It is BREAK signal and character 'g'.
782 set remote interrupt-on-connect [on | off]
783 show remote interrupt-on-connect
784 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
785 remote target when gdb connects to it. This is needed when you debug
788 set remotebreak [on | off]
790 Deprecated. Use "set/show remote interrupt-sequence" instead.
792 tvariable $NAME [ = EXP ]
793 Create or modify a trace state variable.
796 List trace state variables and their values.
798 delete tvariable $NAME ...
799 Delete one or more trace state variables.
802 Evaluate the given expressions without collecting anything into the
803 trace buffer. (Valid in tracepoint actions only.)
805 ftrace FN / FILE:LINE / *ADDR
806 Define a fast tracepoint at the given function, line, or address.
808 * New expression syntax
810 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
811 GDB now parses 0b101010 identically with 42.
815 set follow-exec-mode new|same
816 show follow-exec-mode
817 Control whether GDB reuses the same inferior across an exec call or
818 creates a new one. This is useful to be able to restart the old
819 executable after the inferior having done an exec call.
821 set default-collect EXPR, ...
823 Define a list of expressions to be collected at each tracepoint.
824 This is a useful way to ensure essential items are not overlooked,
825 such as registers or a critical global variable.
827 set disconnected-tracing
828 show disconnected-tracing
829 If set to 1, the target is instructed to continue tracing if it
830 loses its connection to GDB. If 0, the target is to stop tracing
833 set circular-trace-buffer
834 show circular-trace-buffer
835 If set to on, the target is instructed to use a circular trace buffer
836 and discard the oldest trace frames instead of stopping the trace due
837 to a full trace buffer. If set to off, the trace stops when the buffer
838 fills up. Some targets may not support this.
840 set script-extension off|soft|strict
841 show script-extension
842 If set to "off", the debugger does not perform any script language
843 recognition, and all sourced files are assumed to be GDB scripts.
844 If set to "soft" (the default), files are sourced according to
845 filename extension, falling back to GDB scripts if the first
847 If set to "strict", files are sourced according to filename extension.
849 set ada trust-PAD-over-XVS on|off
850 show ada trust-PAD-over-XVS
851 If off, activate a workaround against a bug in the debugging information
852 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
853 the GCC sources for more information about the GNAT encoding and
854 PAD types in particular). It is always safe to set this option to
855 off, but this introduces a slight performance penalty. The default
858 * Python API Improvements
860 ** GDB provides the new class gdb.LazyString. This is useful in
861 some pretty-printing cases. The new method gdb.Value.lazy_string
862 provides a simple way to create objects of this type.
864 ** The fields returned by gdb.Type.fields now have an
865 `is_base_class' attribute.
867 ** The new method gdb.Type.range returns the range of an array type.
869 ** The new method gdb.parse_and_eval can be used to parse and
870 evaluate an expression.
875 Define a trace state variable.
878 Get the current value of a trace state variable.
881 Set desired tracing behavior upon disconnection.
884 Set the trace buffer to be linear or circular.
887 Get data about the tracepoints currently in use.
891 Process record now works correctly with hardware watchpoints.
893 Multiple bug fixes have been made to the mips-irix port, making it
894 much more reliable. In particular:
895 - Debugging threaded applications is now possible again. Previously,
896 GDB would hang while starting the program, or while waiting for
897 the program to stop at a breakpoint.
898 - Attaching to a running process no longer hangs.
899 - An error occurring while loading a core file has been fixed.
900 - Changing the value of the PC register now works again. This fixes
901 problems observed when using the "jump" command, or when calling
902 a function from GDB, or even when assigning a new value to $pc.
903 - With the "finish" and "return" commands, the return value for functions
904 returning a small array is now correctly printed.
905 - It is now possible to break on shared library code which gets executed
906 during a shared library init phase (code executed while executing
907 their .init section). Previously, the breakpoint would have no effect.
908 - GDB is now able to backtrace through the signal handler for
909 non-threaded programs.
911 PIE (Position Independent Executable) programs debugging is now supported.
912 This includes debugging execution of PIC (Position Independent Code) shared
913 libraries although for that, it should be possible to run such libraries as an
916 *** Changes in GDB 7.0
918 * GDB now has an interface for JIT compilation. Applications that
919 dynamically generate code can create symbol files in memory and register
920 them with GDB. For users, the feature should work transparently, and
921 for JIT developers, the interface is documented in the GDB manual in the
922 "JIT Compilation Interface" chapter.
924 * Tracepoints may now be conditional. The syntax is as for
925 breakpoints; either an "if" clause appended to the "trace" command,
926 or the "condition" command is available. GDB sends the condition to
927 the target for evaluation using the same bytecode format as is used
928 for tracepoint actions.
930 * The disassemble command now supports: an optional /r modifier, print the
931 raw instructions in hex as well as in symbolic form, and an optional /m
932 modifier to print mixed source+assembly.
934 * Process record and replay
936 In a architecture environment that supports ``process record and
937 replay'', ``process record and replay'' target can record a log of
938 the process execution, and replay it with both forward and reverse
941 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
942 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
943 set execution-direction {forward|reverse}, for targets that support
946 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
947 feature is available with a native GDB running on kernel version
950 * GDB now has support for multi-byte and wide character sets on the
951 target. Strings whose character type is wchar_t, char16_t, or
952 char32_t are now correctly printed. GDB supports wide- and unicode-
953 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
954 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
955 `printf'. This feature requires iconv to work properly; if your
956 system does not have a working iconv, GDB can use GNU libiconv. See
957 the installation instructions for more information.
959 * GDB now supports automatic retrieval of shared library files from
960 remote targets. To use this feature, specify a system root that begins
961 with the `remote:' prefix, either via the `set sysroot' command or via
962 the `--with-sysroot' configure-time option.
964 * "info sharedlibrary" now takes an optional regex of libraries to show,
965 and it now reports if a shared library has no debugging information.
967 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
968 now complete on file names.
970 * When completing in expressions, gdb will attempt to limit
971 completions to allowable structure or union fields, where appropriate.
972 For instance, consider:
974 # struct example { int f1; double f2; };
975 # struct example variable;
978 If the user types TAB at the end of this command line, the available
979 completions will be "f1" and "f2".
981 * Inlined functions are now supported. They show up in backtraces, and
982 the "step", "next", and "finish" commands handle them automatically.
984 * GDB now supports the token-splicing (##) and stringification (#)
985 operators when expanding macros. It also supports variable-arity
988 * GDB now supports inspecting extra signal information, exported by
989 the new $_siginfo convenience variable. The feature is currently
990 implemented on linux ARM, i386 and amd64.
992 * GDB can now display the VFP floating point registers and NEON vector
993 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
994 can provide these registers (requires Linux 2.6.30 or later). Remote
995 and simulator targets may also provide them.
1000 Search memory for a sequence of bytes.
1003 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1004 operation over reliable transport links. Use of this packet is
1005 controlled by the `set remote noack-packet' command.
1008 Kill the process with the specified process ID. Use this in preference
1009 to `k' when multiprocess protocol extensions are supported.
1012 Obtains additional operating system information
1016 Read or write additional signal information.
1018 * Removed remote protocol undocumented extension
1020 An undocumented extension to the remote protocol's `S' stop reply
1021 packet that permited the stub to pass a process id was removed.
1022 Remote servers should use the `T' stop reply packet instead.
1024 * GDB now supports multiple function calling conventions according to the
1025 DWARF-2 DW_AT_calling_convention function attribute.
1027 * The SH target utilizes the aforementioned change to distinguish between gcc
1028 and Renesas calling convention. It also adds the new CLI commands
1029 `set/show sh calling-convention'.
1031 * GDB can now read compressed debug sections, as produced by GNU gold
1032 with the --compress-debug-sections=zlib flag.
1034 * 64-bit core files are now supported on AIX.
1036 * Thread switching is now supported on Tru64.
1038 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1039 which will be allocated using malloc later in program execution.
1041 * The qXfer:libraries:read remote procotol packet now allows passing a
1042 list of section offsets.
1044 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1045 conditions handling signals delivered during attach or thread creation
1046 have also been fixed.
1048 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1049 From the user's standpoint, all unqualified instances of True and False
1050 are treated as the standard definitions, regardless of context.
1052 * GDB now parses C++ symbol and type names more flexibly. For
1055 template<typename T> class C { };
1058 GDB will now correctly handle all of:
1060 ptype C<char const *>
1061 ptype C<char const*>
1062 ptype C<const char *>
1063 ptype C<const char*>
1065 * New features in the GDB remote stub, gdbserver
1067 - The "--wrapper" command-line argument tells gdbserver to use a
1068 wrapper program to launch programs for debugging.
1070 - On PowerPC and S/390 targets, it is now possible to use a single
1071 gdbserver executable to debug both 32-bit and 64-bit programs.
1072 (This requires gdbserver itself to be built as a 64-bit executable.)
1074 - gdbserver uses the new noack protocol mode for TCP connections to
1075 reduce communications latency, if also supported and enabled in GDB.
1077 - Support for the sparc64-linux-gnu target is now included in
1080 - The amd64-linux build of gdbserver now supports debugging both
1081 32-bit and 64-bit programs.
1083 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1084 now support hardware watchpoints, and will use them automatically
1089 GDB now has support for scripting using Python. Whether this is
1090 available is determined at configure time.
1092 New GDB commands can now be written in Python.
1094 * Ada tasking support
1096 Ada tasks can now be inspected in GDB. The following commands have
1100 Print the list of Ada tasks.
1102 Print detailed information about task number N.
1104 Print the task number of the current task.
1106 Switch the context of debugging to task number N.
1108 * Support for user-defined prefixed commands. The "define" command can
1109 add new commands to existing prefixes, e.g. "target".
1111 * Multi-inferior, multi-process debugging.
1113 GDB now has generalized support for multi-inferior debugging. See
1114 "Debugging Multiple Inferiors" in the manual for more information.
1115 Although availability still depends on target support, the command
1116 set is more uniform now. The GNU/Linux specific multi-forks support
1117 has been migrated to this new framework. This implied some user
1118 visible changes; see "New commands" and also "Removed commands"
1121 * Target descriptions can now describe the target OS ABI. See the
1122 "Target Description Format" section in the user manual for more
1125 * Target descriptions can now describe "compatible" architectures
1126 to indicate that the target can execute applications for a different
1127 architecture in addition to those for the main target architecture.
1128 See the "Target Description Format" section in the user manual for
1131 * Multi-architecture debugging.
1133 GDB now includes general supports for debugging applications on
1134 hybrid systems that use more than one single processor architecture
1135 at the same time. Each such hybrid architecture still requires
1136 specific support to be added. The only hybrid architecture supported
1137 in this version of GDB is the Cell Broadband Engine.
1139 * GDB now supports integrated debugging of Cell/B.E. applications that
1140 use both the PPU and SPU architectures. To enable support for hybrid
1141 Cell/B.E. debugging, you need to configure GDB to support both the
1142 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1143 --enable-targets configure option.
1145 * Non-stop mode debugging.
1147 For some targets, GDB now supports an optional mode of operation in
1148 which you can examine stopped threads while other threads continue
1149 to execute freely. This is referred to as non-stop mode, with the
1150 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1151 section in the user manual for more information.
1153 To be able to support remote non-stop debugging, a remote stub needs
1154 to implement the non-stop mode remote protocol extensions, as
1155 described in the "Remote Non-Stop" section of the user manual. The
1156 GDB remote stub, gdbserver, has been adjusted to support these
1157 extensions on linux targets.
1159 * New commands (for set/show, see "New options" below)
1161 catch syscall [NAME(S) | NUMBER(S)]
1162 Catch system calls. Arguments, which should be names of system
1163 calls or their numbers, mean catch only those syscalls. Without
1164 arguments, every syscall will be caught. When the inferior issues
1165 any of the specified syscalls, GDB will stop and announce the system
1166 call, both when it is called and when its call returns. This
1167 feature is currently available with a native GDB running on the
1168 Linux Kernel, under the following architectures: x86, x86_64,
1169 PowerPC and PowerPC64.
1171 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1173 Search memory for a sequence of bytes.
1175 maint set python print-stack
1176 maint show python print-stack
1177 Show a stack trace when an error is encountered in a Python script.
1180 Invoke CODE by passing it to the Python interpreter.
1185 These allow macros to be defined, undefined, and listed
1189 Show operating system information about processes.
1192 List the inferiors currently under GDB's control.
1195 Switch focus to inferior number NUM.
1198 Detach from inferior number NUM.
1201 Kill inferior number NUM.
1205 set spu stop-on-load
1206 show spu stop-on-load
1207 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1209 set spu auto-flush-cache
1210 show spu auto-flush-cache
1211 Control whether to automatically flush the software-managed cache
1212 during Cell/B.E. debugging.
1214 set sh calling-convention
1215 show sh calling-convention
1216 Control the calling convention used when calling SH target functions.
1219 show debug timestamp
1220 Control display of timestamps with GDB debugging output.
1222 set disassemble-next-line
1223 show disassemble-next-line
1224 Control display of disassembled source lines or instructions when
1227 set remote noack-packet
1228 show remote noack-packet
1229 Set/show the use of remote protocol QStartNoAckMode packet. See above
1230 under "New remote packets."
1232 set remote query-attached-packet
1233 show remote query-attached-packet
1234 Control use of remote protocol `qAttached' (query-attached) packet.
1236 set remote read-siginfo-object
1237 show remote read-siginfo-object
1238 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1241 set remote write-siginfo-object
1242 show remote write-siginfo-object
1243 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1246 set remote reverse-continue
1247 show remote reverse-continue
1248 Control use of remote protocol 'bc' (reverse-continue) packet.
1250 set remote reverse-step
1251 show remote reverse-step
1252 Control use of remote protocol 'bs' (reverse-step) packet.
1254 set displaced-stepping
1255 show displaced-stepping
1256 Control displaced stepping mode. Displaced stepping is a way to
1257 single-step over breakpoints without removing them from the debuggee.
1258 Also known as "out-of-line single-stepping".
1261 show debug displaced
1262 Control display of debugging info for displaced stepping.
1264 maint set internal-error
1265 maint show internal-error
1266 Control what GDB does when an internal error is detected.
1268 maint set internal-warning
1269 maint show internal-warning
1270 Control what GDB does when an internal warning is detected.
1275 Use a wrapper program to launch programs for debugging.
1277 set multiple-symbols (all|ask|cancel)
1278 show multiple-symbols
1279 The value of this variable can be changed to adjust the debugger behavior
1280 when an expression or a breakpoint location contains an ambiguous symbol
1281 name (an overloaded function name, for instance).
1283 set breakpoint always-inserted
1284 show breakpoint always-inserted
1285 Keep breakpoints always inserted in the target, as opposed to inserting
1286 them when resuming the target, and removing them when the target stops.
1287 This option can improve debugger performance on slow remote targets.
1289 set arm fallback-mode (arm|thumb|auto)
1290 show arm fallback-mode
1291 set arm force-mode (arm|thumb|auto)
1293 These commands control how ARM GDB determines whether instructions
1294 are ARM or Thumb. The default for both settings is auto, which uses
1295 the current CPSR value for instructions without symbols; previous
1296 versions of GDB behaved as if "set arm fallback-mode arm".
1298 set disable-randomization
1299 show disable-randomization
1300 Standalone programs run with the virtual address space randomization enabled
1301 by default on some platforms. This option keeps the addresses stable across
1302 multiple debugging sessions.
1306 Control whether other threads are stopped or not when some thread hits
1311 Requests that asynchronous execution is enabled in the target, if available.
1312 In this case, it's possible to resume target in the background, and interact
1313 with GDB while the target is running. "show target-async" displays the
1314 current state of asynchronous execution of the target.
1316 set target-wide-charset
1317 show target-wide-charset
1318 The target-wide-charset is the name of the character set that GDB
1319 uses when printing characters whose type is wchar_t.
1321 set tcp auto-retry (on|off)
1323 set tcp connect-timeout
1324 show tcp connect-timeout
1325 These commands allow GDB to retry failed TCP connections to a remote stub
1326 with a specified timeout period; this is useful if the stub is launched
1327 in parallel with GDB but may not be ready to accept connections immediately.
1329 set libthread-db-search-path
1330 show libthread-db-search-path
1331 Control list of directories which GDB will search for appropriate
1334 set schedule-multiple (on|off)
1335 show schedule-multiple
1336 Allow GDB to resume all threads of all processes or only threads of
1337 the current process.
1341 Use more aggressive caching for accesses to the stack. This improves
1342 performance of remote debugging (particularly backtraces) without
1343 affecting correctness.
1345 set interactive-mode (on|off|auto)
1346 show interactive-mode
1347 Control whether GDB runs in interactive mode (on) or not (off).
1348 When in interactive mode, GDB waits for the user to answer all
1349 queries. Otherwise, GDB does not wait and assumes the default
1350 answer. When set to auto (the default), GDB determines which
1351 mode to use based on the stdin settings.
1356 For program forks, this is replaced by the new more generic `info
1357 inferiors' command. To list checkpoints, you can still use the
1358 `info checkpoints' command, which was an alias for the `info forks'
1362 Replaced by the new `inferior' command. To switch between
1363 checkpoints, you can still use the `restart' command, which was an
1364 alias for the `fork' command.
1367 This is removed, since some targets don't have a notion of
1368 processes. To switch between processes, you can still use the
1369 `inferior' command using GDB's own inferior number.
1372 For program forks, this is replaced by the new more generic `kill
1373 inferior' command. To delete a checkpoint, you can still use the
1374 `delete checkpoint' command, which was an alias for the `delete
1378 For program forks, this is replaced by the new more generic `detach
1379 inferior' command. To detach a checkpoint, you can still use the
1380 `detach checkpoint' command, which was an alias for the `detach
1383 * New native configurations
1385 x86/x86_64 Darwin i[34567]86-*-darwin*
1387 x86_64 MinGW x86_64-*-mingw*
1391 Lattice Mico32 lm32-*
1392 x86 DICOS i[34567]86-*-dicos*
1393 x86_64 DICOS x86_64-*-dicos*
1396 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1397 (mingw32ce) debugging.
1403 These commands were actually not implemented on any target.
1405 *** Changes in GDB 6.8
1407 * New native configurations
1409 NetBSD/hppa hppa*-*netbsd*
1410 Xtensa GNU/Linux xtensa*-*-linux*
1414 NetBSD/hppa hppa*-*-netbsd*
1415 Xtensa GNU/Lunux xtensa*-*-linux*
1417 * Change in command line behavior -- corefiles vs. process ids.
1419 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1420 attaching to process NUMBER fails, GDB no longer attempts to open a
1421 core file named NUMBER. Attaching to a program using the -c option
1422 is no longer supported. Instead, use the '-p' or '--pid' options.
1424 * GDB can now be built as a native debugger for debugging Windows x86
1425 (mingw32) Portable Executable (PE) programs.
1427 * Pending breakpoints no longer change their number when their address
1430 * GDB now supports breakpoints with multiple locations,
1431 including breakpoints on C++ constructors, inside C++ templates,
1432 and in inlined functions.
1434 * GDB's ability to debug optimized code has been improved. GDB more
1435 accurately identifies function bodies and lexical blocks that occupy
1436 more than one contiguous range of addresses.
1438 * Target descriptions can now describe registers for PowerPC.
1440 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1441 registers on PowerPC targets.
1443 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1444 targets even when the libthread_db library is not available.
1446 * The GDB remote stub, gdbserver, now supports the new file transfer
1447 commands (remote put, remote get, and remote delete).
1449 * The GDB remote stub, gdbserver, now supports run and attach in
1450 extended-remote mode.
1452 * hppa*64*-*-hpux11* target broken
1453 The debugger is unable to start a program and fails with the following
1454 error: "Error trying to get information about dynamic linker".
1455 The gdb-6.7 release is also affected.
1457 * GDB now supports the --enable-targets= configure option to allow
1458 building a single GDB executable that supports multiple remote
1459 target architectures.
1461 * GDB now supports debugging C and C++ programs which use the
1462 Decimal Floating Point extension. In addition, the PowerPC target
1463 now has a set of pseudo-registers to inspect decimal float values
1464 stored in two consecutive float registers.
1466 * The -break-insert MI command can optionally create pending
1469 * Improved support for debugging Ada
1470 Many improvements to the Ada language support have been made. These
1472 - Better support for Ada2005 interface types
1473 - Improved handling of arrays and slices in general
1474 - Better support for Taft-amendment types
1475 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1477 - Improved command completion in Ada
1480 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1485 set print frame-arguments (all|scalars|none)
1486 show print frame-arguments
1487 The value of this variable can be changed to control which argument
1488 values should be printed by the debugger when displaying a frame.
1493 Transfer files to and from a remote target, and delete remote files.
1500 Transfer files to and from a remote target, and delete remote files.
1502 * New remote packets
1509 Open, close, read, write, and delete files on the remote system.
1512 Attach to an existing process on the remote system, in extended-remote
1516 Run a new process on the remote system, in extended-remote mode.
1518 *** Changes in GDB 6.7
1520 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1521 bfd, libiberty and opcodes, as revealed by static analysis donated by
1522 Coverity, Inc. (http://scan.coverity.com).
1524 * When looking up multiply-defined global symbols, GDB will now prefer the
1525 symbol definition in the current shared library if it was built using the
1526 -Bsymbolic linker option.
1528 * When the Text User Interface (TUI) is not configured, GDB will now
1529 recognize the -tui command-line option and print a message that the TUI
1532 * The GDB remote stub, gdbserver, now has lower overhead for high
1533 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1535 * GDB for MIPS targets now autodetects whether a remote target provides
1536 32-bit or 64-bit register values.
1538 * Support for C++ member pointers has been improved.
1540 * GDB now understands XML target descriptions, which specify the
1541 target's overall architecture. GDB can read a description from
1542 a local file or over the remote serial protocol.
1544 * Vectors of single-byte data use a new integer type which is not
1545 automatically displayed as character or string data.
1547 * The /s format now works with the print command. It displays
1548 arrays of single-byte integers and pointers to single-byte integers
1551 * Target descriptions can now describe target-specific registers,
1552 for architectures which have implemented the support (currently
1553 only ARM, M68K, and MIPS).
1555 * GDB and the GDB remote stub, gdbserver, now support the XScale
1558 * The GDB remote stub, gdbserver, has been updated to support
1559 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1560 has been rewritten to use the standard GDB remote protocol.
1562 * GDB can now step into C++ functions which are called through thunks.
1564 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1566 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1567 layout. It also supports a TextSeg= and DataSeg= response when only
1568 segment base addresses (rather than offsets) are available.
1570 * The /i format now outputs any trailing branch delay slot instructions
1571 immediately following the last instruction within the count specified.
1573 * The GDB remote protocol "T" stop reply packet now supports a
1574 "library" response. Combined with the new "qXfer:libraries:read"
1575 packet, this response allows GDB to debug shared libraries on targets
1576 where the operating system manages the list of loaded libraries (e.g.
1577 Windows and SymbianOS).
1579 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1580 (DLLs) on Windows and Windows CE targets.
1582 * GDB now supports a faster verification that a .debug file matches its binary
1583 according to its build-id signature, if the signature is present.
1589 Enable or disable hardware flow control (RTS/CTS) on the serial port
1590 when debugging using remote targets.
1592 set mem inaccessible-by-default
1593 show mem inaccessible-by-default
1594 If the target supplies a memory map, for instance via the remote
1595 protocol's "qXfer:memory-map:read" packet, setting this variable
1596 prevents GDB from accessing memory outside the memory map. This
1597 is useful for targets with memory mapped registers or which react
1598 badly to accesses of unmapped address space.
1600 set breakpoint auto-hw
1601 show breakpoint auto-hw
1602 If the target supplies a memory map, for instance via the remote
1603 protocol's "qXfer:memory-map:read" packet, setting this variable
1604 lets GDB use hardware breakpoints automatically for memory regions
1605 where it can not use software breakpoints. This covers both the
1606 "break" command and internal breakpoints used for other commands
1607 including "next" and "finish".
1610 catch exception unhandled
1611 Stop the program execution when Ada exceptions are raised.
1614 Stop the program execution when an Ada assertion failed.
1618 Set an alternate system root for target files. This is a more
1619 general version of "set solib-absolute-prefix", which is now
1620 an alias to "set sysroot".
1623 Provide extended SPU facility status information. This set of
1624 commands is available only when debugging the Cell/B.E. SPU
1627 * New native configurations
1629 OpenBSD/sh sh*-*openbsd*
1632 unset tdesc filename
1634 Use the specified local file as an XML target description, and do
1635 not query the target for its built-in description.
1639 OpenBSD/sh sh*-*-openbsd*
1640 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1641 Toshiba Media Processor mep-elf
1643 * New remote packets
1646 Ignore the specified signals; pass them directly to the debugged program
1647 without stopping other threads or reporting them to GDB.
1649 qXfer:features:read:
1650 Read an XML target description from the target, which describes its
1655 Read or write contents of an spufs file on the target system. These
1656 packets are available only on the Cell/B.E. SPU architecture.
1658 qXfer:libraries:read:
1659 Report the loaded shared libraries. Combined with new "T" packet
1660 response, this packet allows GDB to debug shared libraries on
1661 targets where the operating system manages the list of loaded
1662 libraries (e.g. Windows and SymbianOS).
1666 Support for these obsolete configurations has been removed.
1674 i[34567]86-*-lynxos*
1675 i[34567]86-*-netware*
1676 i[34567]86-*-sco3.2v5*
1677 i[34567]86-*-sco3.2v4*
1679 i[34567]86-*-sysv4.2*
1682 i[34567]86-*-unixware2*
1683 i[34567]86-*-unixware*
1692 * Other removed features
1699 Various m68k-only ROM monitors.
1706 Various Renesas ROM monitors and debugging interfaces for SH and
1711 Support for a Macraigor serial interface to on-chip debugging.
1712 GDB does not directly support the newer parallel or USB
1717 A debug information format. The predecessor to DWARF 2 and
1718 DWARF 3, which are still supported.
1720 Support for the HP aCC compiler on HP-UX/PA-RISC
1722 SOM-encapsulated symbolic debugging information, automatic
1723 invocation of pxdb, and the aCC custom C++ ABI. This does not
1724 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1725 with aCC can still be debugged on an assembly level.
1727 MIPS ".pdr" sections
1729 A MIPS-specific format used to describe stack frame layout
1730 in debugging information.
1734 GDB could work with an older version of Guile to debug
1735 the interpreter and Scheme programs running in it.
1737 set mips stack-arg-size
1738 set mips saved-gpreg-size
1740 Use "set mips abi" to control parameter passing for MIPS.
1742 *** Changes in GDB 6.6
1747 Cell Broadband Engine SPU spu-elf
1749 * GDB can now be configured as a cross-debugger targeting native Windows
1750 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1751 running on a Windows system over TCP/IP to debug Windows programs.
1753 * The GDB remote stub, gdbserver, has been updated to support Windows and
1754 Cygwin debugging. Both single-threaded and multi-threaded programs are
1757 * The "set trust-readonly-sections" command works again. This command was
1758 broken in GDB 6.3, 6.4, and 6.5.
1760 * The "load" command now supports writing to flash memory, if the remote
1761 stub provides the required support.
1763 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1764 longer requires symbolic debug information (e.g. DWARF-2).
1769 unset substitute-path
1770 show substitute-path
1771 Manage a list of substitution rules that GDB uses to rewrite the name
1772 of the directories where the sources are located. This can be useful
1773 for instance when the sources were moved to a different location
1774 between compilation and debugging.
1778 Print each CLI command as it is executed. Each command is prefixed with
1779 a number of `+' symbols representing the nesting depth.
1780 The source command now has a `-v' option to enable the same feature.
1784 The ARM Demon monitor support (RDP protocol, "target rdp").
1786 Kernel Object Display, an embedded debugging feature which only worked with
1787 an obsolete version of Cisco IOS.
1789 The 'set download-write-size' and 'show download-write-size' commands.
1791 * New remote packets
1794 Tell a stub about GDB client features, and request remote target features.
1795 The first feature implemented is PacketSize, which allows the target to
1796 specify the size of packets it can handle - to minimize the number of
1797 packets required and improve performance when connected to a remote
1801 Fetch an OS auxilliary vector from the remote stub. This packet is a
1802 more efficient replacement for qPart:auxv:read.
1804 qXfer:memory-map:read:
1805 Fetch a memory map from the remote stub, including information about
1806 RAM, ROM, and flash memory devices.
1811 Erase and program a flash memory device.
1813 * Removed remote packets
1816 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1817 used it, and only gdbserver implemented it.
1819 *** Changes in GDB 6.5
1823 Renesas M32C/M16C m32c-elf
1825 Morpho Technologies ms1 ms1-elf
1829 init-if-undefined Initialize a convenience variable, but
1830 only if it doesn't already have a value.
1832 The following commands are presently only implemented for native GNU/Linux:
1834 checkpoint Save a snapshot of the program state.
1836 restart <n> Return the program state to a
1837 previously saved state.
1839 info checkpoints List currently saved checkpoints.
1841 delete-checkpoint <n> Delete a previously saved checkpoint.
1843 set|show detach-on-fork Tell gdb whether to detach from a newly
1844 forked process, or to keep debugging it.
1846 info forks List forks of the user program that
1847 are available to be debugged.
1849 fork <n> Switch to debugging one of several
1850 forks of the user program that are
1851 available to be debugged.
1853 delete-fork <n> Delete a fork from the list of forks
1854 that are available to be debugged (and
1855 kill the forked process).
1857 detach-fork <n> Delete a fork from the list of forks
1858 that are available to be debugged (and
1859 allow the process to continue).
1863 Morpho Technologies ms2 ms1-elf
1865 * Improved Windows host support
1867 GDB now builds as a cross debugger hosted on i686-mingw32, including
1868 native console support, and remote communications using either
1869 network sockets or serial ports.
1871 * Improved Modula-2 language support
1873 GDB can now print most types in the Modula-2 syntax. This includes:
1874 basic types, set types, record types, enumerated types, range types,
1875 pointer types and ARRAY types. Procedure var parameters are correctly
1876 printed and hexadecimal addresses and character constants are also
1877 written in the Modula-2 syntax. Best results can be obtained by using
1878 GNU Modula-2 together with the -gdwarf-2 command line option.
1882 The ARM rdi-share module.
1884 The Netware NLM debug server.
1886 *** Changes in GDB 6.4
1888 * New native configurations
1890 OpenBSD/arm arm*-*-openbsd*
1891 OpenBSD/mips64 mips64-*-openbsd*
1895 Morpho Technologies ms1 ms1-elf
1897 * New command line options
1899 --batch-silent As for --batch, but totally silent.
1900 --return-child-result The debugger will exist with the same value
1901 the child (debugged) program exited with.
1902 --eval-command COMMAND, -ex COMMAND
1903 Execute a single GDB CLI command. This may be
1904 specified multiple times and in conjunction
1905 with the --command (-x) option.
1907 * Deprecated commands removed
1909 The following commands, that were deprecated in 2000, have been
1913 set|show arm disassembly-flavor set|show arm disassembler
1914 othernames set arm disassembler
1915 set|show remotedebug set|show debug remote
1916 set|show archdebug set|show debug arch
1917 set|show eventdebug set|show debug event
1920 * New BSD user-level threads support
1922 It is now possible to debug programs using the user-level threads
1923 library on OpenBSD and FreeBSD. Currently supported (target)
1926 FreeBSD/amd64 x86_64-*-freebsd*
1927 FreeBSD/i386 i386-*-freebsd*
1928 OpenBSD/i386 i386-*-openbsd*
1930 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1931 are not yet supported.
1933 * New support for Matsushita MN10300 w/sim added
1934 (Work in progress). mn10300-elf.
1936 * REMOVED configurations and files
1938 VxWorks and the XDR protocol *-*-vxworks
1939 Motorola MCORE mcore-*-*
1940 National Semiconductor NS32000 ns32k-*-*
1942 * New "set print array-indexes" command
1944 After turning this setting "on", GDB prints the index of each element
1945 when displaying arrays. The default is "off" to preserve the previous
1948 * VAX floating point support
1950 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1952 * User-defined command support
1954 In addition to using $arg0..$arg9 for argument passing, it is now possible
1955 to use $argc to determine now many arguments have been passed. See the
1956 section on user-defined commands in the user manual for more information.
1958 *** Changes in GDB 6.3:
1960 * New command line option
1962 GDB now accepts -l followed by a number to set the timeout for remote
1965 * GDB works with GCC -feliminate-dwarf2-dups
1967 GDB now supports a more compact representation of DWARF-2 debug
1968 information using DW_FORM_ref_addr references. These are produced
1969 by GCC with the option -feliminate-dwarf2-dups and also by some
1970 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1971 to use -feliminate-dwarf2-dups.
1973 * Internationalization
1975 When supported by the host system, GDB will be built with
1976 internationalization (libintl). The task of marking up the sources is
1977 continued, we're looking forward to our first translation.
1981 Initial support for debugging programs compiled with the GNAT
1982 implementation of the Ada programming language has been integrated
1983 into GDB. In this release, support is limited to expression evaluation.
1985 * New native configurations
1987 GNU/Linux/m32r m32r-*-linux-gnu
1991 GDB's remote protocol now includes support for the 'p' packet. This
1992 packet is used to fetch individual registers from a remote inferior.
1994 * END-OF-LIFE registers[] compatibility module
1996 GDB's internal register infrastructure has been completely rewritten.
1997 The new infrastructure making possible the implementation of key new
1998 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2001 GDB 6.3 will be the last release to include the the registers[]
2002 compatibility module that allowed out-of-date configurations to
2003 continue to work. This change directly impacts the following
2013 powerpc bdm protocol
2015 Unless there is activity to revive these configurations, they will be
2016 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2018 * OBSOLETE configurations and files
2020 Configurations that have been declared obsolete in this release have
2021 been commented out. Unless there is activity to revive these
2022 configurations, the next release of GDB will have their sources
2023 permanently REMOVED.
2032 *** Changes in GDB 6.2.1:
2034 * MIPS `break main; run' gave an heuristic-fence-post warning
2036 When attempting to run even a simple program, a warning about
2037 heuristic-fence-post being hit would be reported. This problem has
2040 * MIPS IRIX 'long double' crashed GDB
2042 When examining a long double variable, GDB would get a segmentation
2043 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2044 IRIX long double values).
2048 A bug in the VAX stack code was causing problems with the "next"
2049 command. This problem has been fixed.
2051 *** Changes in GDB 6.2:
2053 * Fix for ``many threads''
2055 On GNU/Linux systems that use the NPTL threads library, a program
2056 rapidly creating and deleting threads would confuse GDB leading to the
2059 ptrace: No such process.
2060 thread_db_get_info: cannot get thread info: generic error
2062 This problem has been fixed.
2064 * "-async" and "-noasync" options removed.
2066 Support for the broken "-noasync" option has been removed (it caused
2069 * New ``start'' command.
2071 This command runs the program until the begining of the main procedure.
2073 * New BSD Kernel Data Access Library (libkvm) interface
2075 Using ``target kvm'' it is now possible to debug kernel core dumps and
2076 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2077 platforms. Currently supported (native-only) configurations are:
2079 FreeBSD/amd64 x86_64-*-freebsd*
2080 FreeBSD/i386 i?86-*-freebsd*
2081 NetBSD/i386 i?86-*-netbsd*
2082 NetBSD/m68k m68*-*-netbsd*
2083 NetBSD/sparc sparc-*-netbsd*
2084 OpenBSD/amd64 x86_64-*-openbsd*
2085 OpenBSD/i386 i?86-*-openbsd*
2086 OpenBSD/m68k m68*-openbsd*
2087 OpenBSD/sparc sparc-*-openbsd*
2089 * Signal trampoline code overhauled
2091 Many generic problems with GDB's signal handling code have been fixed.
2092 These include: backtraces through non-contiguous stacks; recognition
2093 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2094 call; backtrace through a signal trampoline; step into and out of
2095 signal handlers; and single-stepping in the signal trampoline.
2097 Please note that kernel bugs are a limiting factor here. These
2098 features have been shown to work on an s390 GNU/Linux system that
2099 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2101 * Cygwin support for DWARF 2 added.
2103 * New native configurations
2105 GNU/Linux/hppa hppa*-*-linux*
2106 OpenBSD/hppa hppa*-*-openbsd*
2107 OpenBSD/m68k m68*-*-openbsd*
2108 OpenBSD/m88k m88*-*-openbsd*
2109 OpenBSD/powerpc powerpc-*-openbsd*
2110 NetBSD/vax vax-*-netbsd*
2111 OpenBSD/vax vax-*-openbsd*
2113 * END-OF-LIFE frame compatibility module
2115 GDB's internal frame infrastructure has been completely rewritten.
2116 The new infrastructure making it possible to support key new features
2117 including DWARF 2 Call Frame Information. To aid in the task of
2118 migrating old configurations to this new infrastructure, a
2119 compatibility module, that allowed old configurations to continue to
2120 work, was also included.
2122 GDB 6.2 will be the last release to include this frame compatibility
2123 module. This change directly impacts the following configurations:
2133 Unless there is activity to revive these configurations, they will be
2134 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2136 * REMOVED configurations and files
2138 Sun 3, running SunOS 3 m68*-*-sunos3*
2139 Sun 3, running SunOS 4 m68*-*-sunos4*
2140 Sun 2, running SunOS 3 m68000-*-sunos3*
2141 Sun 2, running SunOS 4 m68000-*-sunos4*
2142 Motorola 680x0 running LynxOS m68*-*-lynxos*
2143 AT&T 3b1/Unix pc m68*-att-*
2144 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2145 decstation mips-dec-* mips-little-*
2146 riscos mips-*-riscos* mips-*-sysv*
2147 sonymips mips-sony-*
2148 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2150 *** Changes in GDB 6.1.1:
2152 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2154 The TUI (Text-mode User Interface) is now built as part of a default
2155 GDB configuration. It is enabled by either selecting the TUI with the
2156 command line option "-i=tui" or by running the separate "gdbtui"
2157 program. For more information on the TUI, see the manual "Debugging
2160 * Pending breakpoint support (also included in GDB 6.1)
2162 Support has been added to allow you to specify breakpoints in shared
2163 libraries that have not yet been loaded. If a breakpoint location
2164 cannot be found, and the "breakpoint pending" option is set to auto,
2165 GDB queries you if you wish to make the breakpoint pending on a future
2166 shared-library load. If and when GDB resolves the breakpoint symbol,
2167 the pending breakpoint is removed as one or more regular breakpoints
2170 Pending breakpoints are very useful for GCJ Java debugging.
2172 * Fixed ISO-C build problems
2174 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2175 non ISO-C code that stopped them being built using a more strict ISO-C
2176 compiler (e.g., IBM's C compiler).
2178 * Fixed build problem on IRIX 5
2180 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2181 wasn't able to compile compile on an IRIX 5 system.
2183 * Added execute permission to gdb/gdbserver/configure
2185 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2186 permission. This bug would cause configure to fail on a number of
2187 systems (Solaris, IRIX). Ref: server/519.
2189 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2191 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2192 has been updated to use constant array sizes.
2194 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2196 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2197 its generated DWARF Call Frame Info. This encoding was causing GDB to
2198 panic, that panic has been fixed. Ref: gdb/1628.
2200 * Fixed a problem when examining parameters in shared library code.
2202 When examining parameters in optimized shared library code generated
2203 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2204 not available''. GDB now correctly displays the variable's value.
2206 *** Changes in GDB 6.1:
2208 * Removed --with-mmalloc
2210 Support for the mmalloc memory manager has been removed, as it
2211 conflicted with the internal gdb byte cache.
2213 * Changes in AMD64 configurations
2215 The AMD64 target now includes the %cs and %ss registers. As a result
2216 the AMD64 remote protocol has changed; this affects the floating-point
2217 and SSE registers. If you rely on those registers for your debugging,
2218 you should upgrade gdbserver on the remote side.
2220 * Revised SPARC target
2222 The SPARC target has been completely revised, incorporating the
2223 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2224 support for LynxOS and SunOS 4 has been dropped. Calling functions
2225 from within GDB on operating systems with a non-executable stack
2226 (Solaris, OpenBSD) now works.
2230 GDB has a new C++ demangler which does a better job on the mangled
2231 names generated by current versions of g++. It also runs faster, so
2232 with this and other changes gdb should now start faster on large C++
2235 * DWARF 2 Location Expressions
2237 GDB support for location expressions has been extended to support function
2238 arguments and frame bases. Older versions of GDB could crash when they
2241 * C++ nested types and namespaces
2243 GDB's support for nested types and namespaces in C++ has been
2244 improved, especially if you use the DWARF 2 debugging format. (This
2245 is the default for recent versions of GCC on most platforms.)
2246 Specifically, if you have a class "Inner" defined within a class or
2247 namespace "Outer", then GDB realizes that the class's name is
2248 "Outer::Inner", not simply "Inner". This should greatly reduce the
2249 frequency of complaints about not finding RTTI symbols. In addition,
2250 if you are stopped at inside of a function defined within a namespace,
2251 GDB modifies its name lookup accordingly.
2253 * New native configurations
2255 NetBSD/amd64 x86_64-*-netbsd*
2256 OpenBSD/amd64 x86_64-*-openbsd*
2257 OpenBSD/alpha alpha*-*-openbsd*
2258 OpenBSD/sparc sparc-*-openbsd*
2259 OpenBSD/sparc64 sparc64-*-openbsd*
2261 * New debugging protocols
2263 M32R with SDI protocol m32r-*-elf*
2265 * "set prompt-escape-char" command deleted.
2267 The command "set prompt-escape-char" has been deleted. This command,
2268 and its very obscure effet on GDB's prompt, was never documented,
2269 tested, nor mentioned in the NEWS file.
2271 * OBSOLETE configurations and files
2273 Configurations that have been declared obsolete in this release have
2274 been commented out. Unless there is activity to revive these
2275 configurations, the next release of GDB will have their sources
2276 permanently REMOVED.
2278 Sun 3, running SunOS 3 m68*-*-sunos3*
2279 Sun 3, running SunOS 4 m68*-*-sunos4*
2280 Sun 2, running SunOS 3 m68000-*-sunos3*
2281 Sun 2, running SunOS 4 m68000-*-sunos4*
2282 Motorola 680x0 running LynxOS m68*-*-lynxos*
2283 AT&T 3b1/Unix pc m68*-att-*
2284 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2285 decstation mips-dec-* mips-little-*
2286 riscos mips-*-riscos* mips-*-sysv*
2287 sonymips mips-sony-*
2288 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2290 * REMOVED configurations and files
2292 SGI Irix-4.x mips-sgi-irix4 or iris4
2293 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2294 Z8000 simulator z8k-zilog-none or z8ksim
2295 Matsushita MN10200 w/simulator mn10200-*-*
2296 H8/500 simulator h8500-hitachi-hms or h8500hms
2297 HP/PA running BSD hppa*-*-bsd*
2298 HP/PA running OSF/1 hppa*-*-osf*
2299 HP/PA Pro target hppa*-*-pro*
2300 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2301 386BSD i[3456]86-*-bsd*
2302 Sequent family i[3456]86-sequent-sysv4*
2303 i[3456]86-sequent-sysv*
2304 i[3456]86-sequent-bsd*
2305 SPARC running LynxOS sparc-*-lynxos*
2306 SPARC running SunOS 4 sparc-*-sunos4*
2307 Tsqware Sparclet sparclet-*-*
2308 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2310 *** Changes in GDB 6.0:
2314 Support for debugging the Objective-C programming language has been
2315 integrated into GDB.
2317 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2319 DWARF 2's Call Frame Information makes available compiler generated
2320 information that more exactly describes the program's run-time stack.
2321 By using this information, GDB is able to provide more robust stack
2324 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2325 have been updated to use a new backtrace mechanism which includes
2326 DWARF 2 CFI support.
2330 GDB's remote protocol has been extended to include support for hosted
2331 file I/O (where the remote target uses GDB's file system). See GDB's
2332 remote protocol documentation for details.
2334 * All targets using the new architecture framework.
2336 All of GDB's targets have been updated to use the new internal
2337 architecture framework. The way is now open for future GDB releases
2338 to include cross-architecture native debugging support (i386 on amd64,
2341 * GNU/Linux's Thread Local Storage (TLS)
2343 GDB now includes support for for the GNU/Linux implementation of
2344 per-thread variables.
2346 * GNU/Linux's Native POSIX Thread Library (NPTL)
2348 GDB's thread code has been updated to work with either the new
2349 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2351 * Separate debug info.
2353 GDB, in conjunction with BINUTILS, now supports a mechanism for
2354 automatically loading debug information from a separate file. Instead
2355 of shipping full debug and non-debug versions of system libraries,
2356 system integrators can now instead ship just the stripped libraries
2357 and optional debug files.
2359 * DWARF 2 Location Expressions
2361 DWARF 2 Location Expressions allow the compiler to more completely
2362 describe the location of variables (even in optimized code) to the
2365 GDB now includes preliminary support for location expressions (support
2366 for DW_OP_piece is still missing).
2370 A number of long standing bugs that caused GDB to die while starting a
2371 Java application have been fixed. GDB's Java support is now
2372 considered "useable".
2374 * GNU/Linux support for fork, vfork, and exec.
2376 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2377 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2380 * GDB supports logging output to a file
2382 There are two new commands, "set logging" and "show logging", which can be
2383 used to capture GDB's output to a file.
2385 * The meaning of "detach" has changed for gdbserver
2387 The "detach" command will now resume the application, as documented. To
2388 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2391 * d10v, m68hc11 `regs' command deprecated
2393 The `info registers' command has been updated so that it displays the
2394 registers using a format identical to the old `regs' command.
2398 A new command, "maint set profile on/off", has been added. This command can
2399 be used to enable or disable profiling while running GDB, to profile a
2400 session or a set of commands. In addition there is a new configure switch,
2401 "--enable-profiling", which will cause GDB to be compiled with profiling
2402 data, for more informative profiling results.
2404 * Default MI syntax changed to "mi2".
2406 The default MI (machine interface) syntax, enabled by the command line
2407 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2408 "mi1", can be enabled by specifying the option "-i=mi1".
2410 Support for the original "mi0" syntax (included in GDB 5.0) has been
2413 Fix for gdb/192: removed extraneous space when displaying frame level.
2414 Fix for gdb/672: update changelist is now output in mi list format.
2415 Fix for gdb/702: a -var-assign that updates the value now shows up
2416 in a subsequent -var-update.
2418 * New native configurations.
2420 FreeBSD/amd64 x86_64-*-freebsd*
2422 * Multi-arched targets.
2424 HP/PA HPUX11 hppa*-*-hpux*
2425 Renesas M32R/D w/simulator m32r-*-elf*
2427 * OBSOLETE configurations and files
2429 Configurations that have been declared obsolete in this release have
2430 been commented out. Unless there is activity to revive these
2431 configurations, the next release of GDB will have their sources
2432 permanently REMOVED.
2434 Z8000 simulator z8k-zilog-none or z8ksim
2435 Matsushita MN10200 w/simulator mn10200-*-*
2436 H8/500 simulator h8500-hitachi-hms or h8500hms
2437 HP/PA running BSD hppa*-*-bsd*
2438 HP/PA running OSF/1 hppa*-*-osf*
2439 HP/PA Pro target hppa*-*-pro*
2440 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2441 Sequent family i[3456]86-sequent-sysv4*
2442 i[3456]86-sequent-sysv*
2443 i[3456]86-sequent-bsd*
2444 Tsqware Sparclet sparclet-*-*
2445 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2447 * REMOVED configurations and files
2450 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2451 IBM AIX PS/2 i[3456]86-*-aix
2452 i386 running Mach 3.0 i[3456]86-*-mach3*
2453 i386 running Mach i[3456]86-*-mach*
2454 i386 running OSF/1 i[3456]86-*osf1mk*
2455 HP/Apollo 68k Family m68*-apollo*-sysv*,
2457 m68*-hp-bsd*, m68*-hp-hpux*
2458 Argonaut Risc Chip (ARC) arc-*-*
2459 Mitsubishi D30V d30v-*-*
2460 Fujitsu FR30 fr30-*-elf*
2461 OS/9000 i[34]86-*-os9k
2462 I960 with MON960 i960-*-coff
2464 * MIPS $fp behavior changed
2466 The convenience variable $fp, for the MIPS, now consistently returns
2467 the address of the current frame's base. Previously, depending on the
2468 context, $fp could refer to either $sp or the current frame's base
2469 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2470 The GNU Source-Level Debugger''.
2472 *** Changes in GDB 5.3:
2474 * GNU/Linux shared library multi-threaded performance improved.
2476 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2477 `/proc', in preference to `ptrace' for memory reads. This may result
2478 in an improvement in the start-up time of multi-threaded, shared
2479 library applications when run under GDB. One GDB user writes: ``loads
2480 shared libs like mad''.
2482 * ``gdbserver'' now supports multi-threaded applications on some targets
2484 Support for debugging multi-threaded applications which use
2485 the GNU/Linux LinuxThreads package has been added for
2486 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2487 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2489 * GDB now supports C/C++ preprocessor macros.
2491 GDB now expands preprocessor macro invocations in C/C++ expressions,
2492 and provides various commands for showing macro definitions and how
2495 The new command `macro expand EXPRESSION' expands any macro
2496 invocations in expression, and shows the result.
2498 The new command `show macro MACRO-NAME' shows the definition of the
2499 macro named MACRO-NAME, and where it was defined.
2501 Most compilers don't include information about macros in the debugging
2502 information by default. In GCC 3.1, for example, you need to compile
2503 your program with the options `-gdwarf-2 -g3'. If the macro
2504 information is present in the executable, GDB will read it.
2506 * Multi-arched targets.
2508 DEC Alpha (partial) alpha*-*-*
2509 DEC VAX (partial) vax-*-*
2511 National Semiconductor NS32000 (partial) ns32k-*-*
2512 Motorola 68000 (partial) m68k-*-*
2513 Motorola MCORE mcore-*-*
2517 Fujitsu FRV architecture added by Red Hat frv*-*-*
2520 * New native configurations
2522 Alpha NetBSD alpha*-*-netbsd*
2523 SH NetBSD sh*-*-netbsdelf*
2524 MIPS NetBSD mips*-*-netbsd*
2525 UltraSPARC NetBSD sparc64-*-netbsd*
2527 * OBSOLETE configurations and files
2529 Configurations that have been declared obsolete in this release have
2530 been commented out. Unless there is activity to revive these
2531 configurations, the next release of GDB will have their sources
2532 permanently REMOVED.
2534 Mitsubishi D30V d30v-*-*
2535 OS/9000 i[34]86-*-os9k
2536 IBM AIX PS/2 i[3456]86-*-aix
2537 Fujitsu FR30 fr30-*-elf*
2538 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2539 Argonaut Risc Chip (ARC) arc-*-*
2540 i386 running Mach 3.0 i[3456]86-*-mach3*
2541 i386 running Mach i[3456]86-*-mach*
2542 i386 running OSF/1 i[3456]86-*osf1mk*
2543 HP/Apollo 68k Family m68*-apollo*-sysv*,
2545 m68*-hp-bsd*, m68*-hp-hpux*
2546 I960 with MON960 i960-*-coff
2548 * OBSOLETE languages
2550 CHILL, a Pascal like language used by telecommunications companies.
2552 * REMOVED configurations and files
2554 AMD 29k family via UDI a29k-amd-udi, udi29k
2555 A29K VxWorks a29k-*-vxworks
2556 AMD 29000 embedded, using EBMON a29k-none-none
2557 AMD 29000 embedded with COFF a29k-none-coff
2558 AMD 29000 embedded with a.out a29k-none-aout
2560 testsuite/gdb.hp/gdb.threads-hp/ directory
2562 * New command "set max-user-call-depth <nnn>"
2564 This command allows the user to limit the call depth of user-defined
2565 commands. The default is 1024.
2567 * Changes in FreeBSD/i386 native debugging.
2569 Support for the "generate-core-file" has been added.
2571 * New commands "dump", "append", and "restore".
2573 These commands allow data to be copied from target memory
2574 to a bfd-format or binary file (dump and append), and back
2575 from a file into memory (restore).
2577 * Improved "next/step" support on multi-processor Alpha Tru64.
2579 The previous single-step mechanism could cause unpredictable problems,
2580 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2581 of a software single-step mechanism prevents this.
2583 *** Changes in GDB 5.2.1:
2591 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2592 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2593 Fix, by Joel Brobecker imported from mainline.
2595 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2596 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2597 Fix, by Fred Fish, imported from mainline.
2599 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2600 Surprisingly enough, it works now.
2601 By Michal Ludvig, imported from mainline.
2603 i386 hardware watchpoint support:
2604 avoid misses on second run for some targets.
2605 By Pierre Muller, imported from mainline.
2607 *** Changes in GDB 5.2:
2609 * New command "set trust-readonly-sections on[off]".
2611 This command is a hint that tells gdb that read-only sections
2612 really are read-only (ie. that their contents will not change).
2613 In this mode, gdb will go to the object file rather than the
2614 target to read memory from read-only sections (such as ".text").
2615 This can be a significant performance improvement on some
2616 (notably embedded) targets.
2618 * New command "generate-core-file" (or "gcore").
2620 This new gdb command allows the user to drop a core file of the child
2621 process state at any time. So far it's been implemented only for
2622 GNU/Linux and Solaris, but should be relatively easily ported to other
2623 hosts. Argument is core file name (defaults to core.<pid>).
2625 * New command line option
2627 GDB now accepts --pid or -p followed by a process id.
2629 * Change in command line behavior -- corefiles vs. process ids.
2631 There is a subtle behavior in the way in which GDB handles
2632 command line arguments. The first non-flag argument is always
2633 a program to debug, but the second non-flag argument may either
2634 be a corefile or a process id. Previously, GDB would attempt to
2635 open the second argument as a corefile, and if that failed, would
2636 issue a superfluous error message and then attempt to attach it as
2637 a process. Now, if the second argument begins with a non-digit,
2638 it will be treated as a corefile. If it begins with a digit,
2639 GDB will attempt to attach it as a process, and if no such process
2640 is found, will then attempt to open it as a corefile.
2642 * Changes in ARM configurations.
2644 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2645 configuration is fully multi-arch.
2647 * New native configurations
2649 ARM NetBSD arm*-*-netbsd*
2650 x86 OpenBSD i[3456]86-*-openbsd*
2651 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2652 Sparc64 running FreeBSD sparc64-*-freebsd*
2656 Sanyo XStormy16 xstormy16-elf
2658 * OBSOLETE configurations and files
2660 Configurations that have been declared obsolete in this release have
2661 been commented out. Unless there is activity to revive these
2662 configurations, the next release of GDB will have their sources
2663 permanently REMOVED.
2665 AMD 29k family via UDI a29k-amd-udi, udi29k
2666 A29K VxWorks a29k-*-vxworks
2667 AMD 29000 embedded, using EBMON a29k-none-none
2668 AMD 29000 embedded with COFF a29k-none-coff
2669 AMD 29000 embedded with a.out a29k-none-aout
2671 testsuite/gdb.hp/gdb.threads-hp/ directory
2673 * REMOVED configurations and files
2675 TI TMS320C80 tic80-*-*
2677 PowerPC Solaris powerpcle-*-solaris*
2678 PowerPC Windows NT powerpcle-*-cygwin32
2679 PowerPC Netware powerpc-*-netware*
2680 Harris/CXUX m88k m88*-harris-cxux*
2681 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2682 ns32k-utek-sysv* ns32k-utek-*
2683 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2684 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2685 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2686 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2687 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2689 * Changes to command line processing
2691 The new `--args' feature can be used to specify command-line arguments
2692 for the inferior from gdb's command line.
2694 * Changes to key bindings
2696 There is a new `operate-and-get-next' function bound to `C-o'.
2698 *** Changes in GDB 5.1.1
2700 Fix compile problem on DJGPP.
2702 Fix a problem with floating-point registers on the i386 being
2705 Fix to stop GDB crashing on .debug_str debug info.
2707 Numerous documentation fixes.
2709 Numerous testsuite fixes.
2711 *** Changes in GDB 5.1:
2713 * New native configurations
2715 Alpha FreeBSD alpha*-*-freebsd*
2716 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2717 MIPS GNU/Linux mips*-*-linux*
2718 MIPS SGI Irix 6.x mips*-sgi-irix6*
2719 ia64 AIX ia64-*-aix*
2720 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2724 Motorola 68HC11 and 68HC12 m68hc11-elf
2726 UltraSparc running GNU/Linux sparc64-*-linux*
2728 * OBSOLETE configurations and files
2730 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2731 Harris/CXUX m88k m88*-harris-cxux*
2732 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2733 ns32k-utek-sysv* ns32k-utek-*
2734 TI TMS320C80 tic80-*-*
2736 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2737 PowerPC Solaris powerpcle-*-solaris*
2738 PowerPC Windows NT powerpcle-*-cygwin32
2739 PowerPC Netware powerpc-*-netware*
2740 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2741 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2742 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2743 Apple Macintosh (MPW) host N/A
2745 stuff.c (Program to stuff files into a specially prepared space in kdb)
2746 kdb-start.c (Main loop for the standalone kernel debugger)
2748 Configurations that have been declared obsolete in this release have
2749 been commented out. Unless there is activity to revive these
2750 configurations, the next release of GDB will have their sources
2751 permanently REMOVED.
2753 * REMOVED configurations and files
2755 Altos 3068 m68*-altos-*
2756 Convex c1-*-*, c2-*-*
2758 ARM RISCix arm-*-* (as host)
2762 * GDB has been converted to ISO C.
2764 GDB's source code has been converted to ISO C. In particular, the
2765 sources are fully protoized, and rely on standard headers being
2770 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2772 * The MI enabled by default.
2774 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2775 revised and enabled by default. Packages which use GDB as a debugging
2776 engine behind a UI or another front end are encouraged to switch to
2777 using the GDB/MI interface, instead of the old annotations interface
2778 which is now deprecated.
2780 * Support for debugging Pascal programs.
2782 GDB now includes support for debugging Pascal programs. The following
2783 main features are supported:
2785 - Pascal-specific data types such as sets;
2787 - automatic recognition of Pascal sources based on file-name
2790 - Pascal-style display of data types, variables, and functions;
2792 - a Pascal expression parser.
2794 However, some important features are not yet supported.
2796 - Pascal string operations are not supported at all;
2798 - there are some problems with boolean types;
2800 - Pascal type hexadecimal constants are not supported
2801 because they conflict with the internal variables format;
2803 - support for Pascal objects and classes is not full yet;
2805 - unlike Pascal, GDB is case-sensitive for symbol names.
2807 * Changes in completion.
2809 Commands such as `shell', `run' and `set args', which pass arguments
2810 to inferior programs, now complete on file names, similar to what
2811 users expect at the shell prompt.
2813 Commands which accept locations, such as `disassemble', `print',
2814 `breakpoint', `until', etc. now complete on filenames as well as
2815 program symbols. Thus, if you type "break foob TAB", and the source
2816 files linked into the programs include `foobar.c', that file name will
2817 be one of the candidates for completion. However, file names are not
2818 considered for completion after you typed a colon that delimits a file
2819 name from a name of a function in that file, as in "break foo.c:bar".
2821 `set demangle-style' completes on available demangling styles.
2823 * New platform-independent commands:
2825 It is now possible to define a post-hook for a command as well as a
2826 hook that runs before the command. For more details, see the
2827 documentation of `hookpost' in the GDB manual.
2829 * Changes in GNU/Linux native debugging.
2831 Support for debugging multi-threaded programs has been completely
2832 revised for all platforms except m68k and sparc. You can now debug as
2833 many threads as your system allows you to have.
2835 Attach/detach is supported for multi-threaded programs.
2837 Support for SSE registers was added for x86. This doesn't work for
2838 multi-threaded programs though.
2840 * Changes in MIPS configurations.
2842 Multi-arch support is enabled for all MIPS configurations.
2844 GDB can now be built as native debugger on SGI Irix 6.x systems for
2845 debugging n32 executables. (Debugging 64-bit executables is not yet
2848 * Unified support for hardware watchpoints in all x86 configurations.
2850 Most (if not all) native x86 configurations support hardware-assisted
2851 breakpoints and watchpoints in a unified manner. This support
2852 implements debug register sharing between watchpoints, which allows to
2853 put a virtually infinite number of watchpoints on the same address,
2854 and also supports watching regions up to 16 bytes with several debug
2857 The new maintenance command `maintenance show-debug-regs' toggles
2858 debugging print-outs in functions that insert, remove, and test
2859 watchpoints and hardware breakpoints.
2861 * Changes in the DJGPP native configuration.
2863 New command ``info dos sysinfo'' displays assorted information about
2864 the CPU, OS, memory, and DPMI server.
2866 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2867 display information about segment descriptors stored in GDT, LDT, and
2870 New commands ``info dos pde'' and ``info dos pte'' display entries
2871 from Page Directory and Page Tables (for now works with CWSDPMI only).
2872 New command ``info dos address-pte'' displays the Page Table entry for
2873 a given linear address.
2875 GDB can now pass command lines longer than 126 characters to the
2876 program being debugged (requires an update to the libdbg.a library
2877 which is part of the DJGPP development kit).
2879 DWARF2 debug info is now supported.
2881 It is now possible to `step' and `next' through calls to `longjmp'.
2883 * Changes in documentation.
2885 All GDB documentation was converted to GFDL, the GNU Free
2886 Documentation License.
2888 Tracepoints-related commands are now fully documented in the GDB
2891 TUI, the Text-mode User Interface, is now documented in the manual.
2893 Tracepoints-related commands are now fully documented in the GDB
2896 The "GDB Internals" manual now has an index. It also includes
2897 documentation of `ui_out' functions, GDB coding standards, x86
2898 hardware watchpoints, and memory region attributes.
2900 * GDB's version number moved to ``version.in''
2902 The Makefile variable VERSION has been replaced by the file
2903 ``version.in''. People creating GDB distributions should update the
2904 contents of this file.
2908 GUD support is now a standard part of the EMACS distribution.
2910 *** Changes in GDB 5.0:
2912 * Improved support for debugging FP programs on x86 targets
2914 Unified and much-improved support for debugging floating-point
2915 programs on all x86 targets. In particular, ``info float'' now
2916 displays the FP registers in the same format on all x86 targets, with
2917 greater level of detail.
2919 * Improvements and bugfixes in hardware-assisted watchpoints
2921 It is now possible to watch array elements, struct members, and
2922 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2923 on x86 targets no longer erroneously trigger when the address is
2926 * Improvements in the native DJGPP version of GDB
2928 The distribution now includes all the scripts and auxiliary files
2929 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2930 machines ``out of the box''.
2932 The DJGPP version can now debug programs that use signals. It is
2933 possible to catch signals that happened in the debuggee, deliver
2934 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2935 would kill the program being debugged.) Programs that hook hardware
2936 interrupts (keyboard, timer, etc.) can also be debugged.
2938 It is now possible to debug DJGPP programs that redirect their
2939 standard handles or switch them to raw (as opposed to cooked) mode, or
2940 even close them. The command ``run < foo > bar'' works as expected,
2941 and ``info terminal'' reports useful information about the debuggee's
2942 terminal, including raw/cooked mode, redirection, etc.
2944 The DJGPP version now uses termios functions for console I/O, which
2945 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2948 DOS-style file names with drive letters are now fully supported by
2951 It is now possible to debug DJGPP programs that switch their working
2952 directory. It is also possible to rerun the debuggee any number of
2953 times without restarting GDB; thus, you can use the same setup,
2954 breakpoints, etc. for many debugging sessions.
2956 * New native configurations
2958 ARM GNU/Linux arm*-*-linux*
2959 PowerPC GNU/Linux powerpc-*-linux*
2963 Motorola MCore mcore-*-*
2964 x86 VxWorks i[3456]86-*-vxworks*
2965 PowerPC VxWorks powerpc-*-vxworks*
2966 TI TMS320C80 tic80-*-*
2968 * OBSOLETE configurations
2970 Altos 3068 m68*-altos-*
2971 Convex c1-*-*, c2-*-*
2973 ARM RISCix arm-*-* (as host)
2976 Configurations that have been declared obsolete will be commented out,
2977 but the code will be left in place. If there is no activity to revive
2978 these configurations before the next release of GDB, the sources will
2979 be permanently REMOVED.
2981 * Gould support removed
2983 Support for the Gould PowerNode and NP1 has been removed.
2985 * New features for SVR4
2987 On SVR4 native platforms (such as Solaris), if you attach to a process
2988 without first loading a symbol file, GDB will now attempt to locate and
2989 load symbols from the running process's executable file.
2991 * Many C++ enhancements
2993 C++ support has been greatly improved. Overload resolution now works properly
2994 in almost all cases. RTTI support is on the way.
2996 * Remote targets can connect to a sub-program
2998 A popen(3) style serial-device has been added. This device starts a
2999 sub-process (such as a stand-alone simulator) and then communicates
3000 with that. The sub-program to run is specified using the syntax
3001 ``|<program> <args>'' vis:
3003 (gdb) set remotedebug 1
3004 (gdb) target extended-remote |mn10300-elf-sim program-args
3006 * MIPS 64 remote protocol
3008 A long standing bug in the mips64 remote protocol where by GDB
3009 expected certain 32 bit registers (ex SR) to be transfered as 32
3010 instead of 64 bits has been fixed.
3012 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3013 added to provide backward compatibility with older versions of GDB.
3015 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3017 The command ``set remotebinarydownload'' command has been replaced by
3018 ``set remote X-packet''. Other commands in ``set remote'' family
3019 include ``set remote P-packet''.
3021 * Breakpoint commands accept ranges.
3023 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3024 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3025 ``tracepoint passcount'' also accepts a range of tracepoints.
3027 * ``apropos'' command added.
3029 The ``apropos'' command searches through command names and
3030 documentation strings, printing out matches, making it much easier to
3031 try to find a command that does what you are looking for.
3035 A new machine oriented interface (MI) has been added to GDB. This
3036 interface is designed for debug environments running GDB as a separate
3037 process. This is part of the long term libGDB project. See the
3038 "GDB/MI" chapter of the GDB manual for further information. It can be
3039 enabled by configuring with:
3041 .../configure --enable-gdbmi
3043 *** Changes in GDB-4.18:
3045 * New native configurations
3047 HP-UX 10.20 hppa*-*-hpux10.20
3048 HP-UX 11.x hppa*-*-hpux11.0*
3049 M68K GNU/Linux m68*-*-linux*
3053 Fujitsu FR30 fr30-*-elf*
3054 Intel StrongARM strongarm-*-*
3055 Mitsubishi D30V d30v-*-*
3057 * OBSOLETE configurations
3059 Gould PowerNode, NP1 np1-*-*, pn-*-*
3061 Configurations that have been declared obsolete will be commented out,
3062 but the code will be left in place. If there is no activity to revive
3063 these configurations before the next release of GDB, the sources will
3064 be permanently REMOVED.
3068 As a compatibility experiment, GDB's source files buildsym.h and
3069 buildsym.c have been converted to pure standard C, no longer
3070 containing any K&R compatibility code. We believe that all systems in
3071 use today either come with a standard C compiler, or have a GCC port
3072 available. If this is not true, please report the affected
3073 configuration to bug-gdb@gnu.org immediately. See the README file for
3074 information about getting a standard C compiler if you don't have one
3079 GDB now uses readline 2.2.
3081 * set extension-language
3083 You can now control the mapping between filename extensions and source
3084 languages by using the `set extension-language' command. For instance,
3085 you can ask GDB to treat .c files as C++ by saying
3086 set extension-language .c c++
3087 The command `info extensions' lists all of the recognized extensions
3088 and their associated languages.
3090 * Setting processor type for PowerPC and RS/6000
3092 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3093 you can use the `set processor' command to specify what variant of the
3094 PowerPC family you are debugging. The command
3098 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3099 following PowerPC and RS6000 variants:
3101 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3102 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3104 403GC IBM PowerPC 403GC
3105 505 Motorola PowerPC 505
3106 860 Motorola PowerPC 860 or 850
3107 601 Motorola PowerPC 601
3108 602 Motorola PowerPC 602
3109 603 Motorola/IBM PowerPC 603 or 603e
3110 604 Motorola PowerPC 604 or 604e
3111 750 Motorola/IBM PowerPC 750 or 750
3113 At the moment, this command just tells GDB what to name the
3114 special-purpose processor registers. Since almost all the affected
3115 registers are inaccessible to user-level programs, this command is
3116 only useful for remote debugging in its present form.
3120 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3121 more extensive support for HP-UX. Added features include shared
3122 library support, kernel threads and hardware watchpoints for 11.00,
3123 support for HP's ANSI C and C++ compilers, and a compatibility mode
3124 for xdb and dbx commands.
3128 HP's donation includes the new concept of catchpoints, which is a
3129 generalization of the old catch command. On HP-UX, it is now possible
3130 to catch exec, fork, and vfork, as well as library loading.
3132 This means that the existing catch command has changed; its first
3133 argument now specifies the type of catch to be set up. See the
3134 output of "help catch" for a list of catchpoint types.
3136 * Debugging across forks
3138 On HP-UX, you can choose which process to debug when a fork() happens
3143 HP has donated a curses-based terminal user interface (TUI). To get
3144 it, build with --enable-tui. Although this can be enabled for any
3145 configuration, at present it only works for native HP debugging.
3147 * GDB remote protocol additions
3149 A new protocol packet 'X' that writes binary data is now available.
3150 Default behavior is to try 'X', then drop back to 'M' if the stub
3151 fails to respond. The settable variable `remotebinarydownload'
3152 allows explicit control over the use of 'X'.
3154 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3155 full 64-bit address. The command
3157 set remoteaddresssize 32
3159 can be used to revert to the old behaviour. For existing remote stubs
3160 the change should not be noticed, as the additional address information
3163 In order to assist in debugging stubs, you may use the maintenance
3164 command `packet' to send any text string to the stub. For instance,
3166 maint packet heythere
3168 sends the packet "$heythere#<checksum>". Note that it is very easy to
3169 disrupt a debugging session by sending the wrong packet at the wrong
3172 The compare-sections command allows you to compare section data on the
3173 target to what is in the executable file without uploading or
3174 downloading, by comparing CRC checksums.
3176 * Tracing can collect general expressions
3178 You may now collect general expressions at tracepoints. This requires
3179 further additions to the target-side stub; see tracepoint.c and
3180 doc/agentexpr.texi for further details.
3182 * mask-address variable for Mips
3184 For Mips targets, you may control the zeroing of the upper 32 bits of
3185 a 64-bit address by entering `set mask-address on'. This is mainly
3186 of interest to users of embedded R4xxx and R5xxx processors.
3188 * Higher serial baud rates
3190 GDB's serial code now allows you to specify baud rates 57600, 115200,
3191 230400, and 460800 baud. (Note that your host system may not be able
3192 to achieve all of these rates.)
3196 The i960 configuration now includes an initial implementation of a
3197 builtin simulator, contributed by Jim Wilson.
3200 *** Changes in GDB-4.17:
3202 * New native configurations
3204 Alpha GNU/Linux alpha*-*-linux*
3205 Unixware 2.x i[3456]86-unixware2*
3206 Irix 6.x mips*-sgi-irix6*
3207 PowerPC GNU/Linux powerpc-*-linux*
3208 PowerPC Solaris powerpcle-*-solaris*
3209 Sparc GNU/Linux sparc-*-linux*
3210 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3214 Argonaut Risc Chip (ARC) arc-*-*
3215 Hitachi H8/300S h8300*-*-*
3216 Matsushita MN10200 w/simulator mn10200-*-*
3217 Matsushita MN10300 w/simulator mn10300-*-*
3218 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3219 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3220 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3221 Mitsubishi D10V w/simulator d10v-*-*
3222 Mitsubishi M32R/D w/simulator m32r-*-elf*
3223 Tsqware Sparclet sparclet-*-*
3224 NEC V850 w/simulator v850-*-*
3226 * New debugging protocols
3228 ARM with RDI protocol arm*-*-*
3229 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3230 DDB and LSI variants of PMON protocol mips*-*-*
3231 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3232 PowerPC with SDS protocol powerpc{,le}-*-eabi
3233 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3237 All configurations can now understand and use the DWARF 2 debugging
3238 format. The choice is automatic, if the symbol file contains DWARF 2
3243 GDB now includes basic Java language support. This support is
3244 only useful with Java compilers that produce native machine code.
3246 * solib-absolute-prefix and solib-search-path
3248 For SunOS and SVR4 shared libraries, you may now set the prefix for
3249 loading absolute shared library symbol files, and the search path for
3250 locating non-absolute shared library symbol files.
3252 * Live range splitting
3254 GDB can now effectively debug code for which GCC has performed live
3255 range splitting as part of its optimization. See gdb/doc/LRS for
3256 more details on the expected format of the stabs information.
3260 GDB's support for the GNU Hurd, including thread debugging, has been
3261 updated to work with current versions of the Hurd.
3265 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3266 instruction set. ARM GDB automatically detects when Thumb
3267 instructions are in use, and adjusts disassembly and backtracing
3272 GDB's MIPS target configurations now handle the MIP16 16-bit
3277 GDB now includes support for overlays; if an executable has been
3278 linked such that multiple sections are based at the same address, GDB
3279 will decide which section to use for symbolic info. You can choose to
3280 control the decision manually, using overlay commands, or implement
3281 additional target-side support and use "overlay load-target" to bring
3282 in the overlay mapping. Do "help overlay" for more detail.
3286 The command "info symbol <address>" displays information about
3287 the symbol at the specified address.
3291 The standard remote protocol now includes an extension that allows
3292 asynchronous collection and display of trace data. This requires
3293 extensive support in the target-side debugging stub. Tracing mode
3294 includes a new interaction mode in GDB and new commands: see the
3295 file tracepoint.c for more details.
3299 Configurations for embedded MIPS now include a simulator contributed
3300 by Cygnus Solutions. The simulator supports the instruction sets
3301 of most MIPS variants.
3305 Sparc configurations may now include the ERC32 simulator contributed
3306 by the European Space Agency. The simulator is not built into
3307 Sparc targets by default; configure with --enable-sim to include it.
3311 For target configurations that may include multiple variants of a
3312 basic architecture (such as MIPS and SH), you may now set the
3313 architecture explicitly. "set arch" sets, "info arch" lists
3314 the possible architectures.
3316 *** Changes in GDB-4.16:
3318 * New native configurations
3320 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3321 M68K NetBSD m68k-*-netbsd*
3322 PowerPC AIX 4.x powerpc-*-aix*
3323 PowerPC MacOS powerpc-*-macos*
3324 PowerPC Windows NT powerpcle-*-cygwin32
3325 RS/6000 AIX 4.x rs6000-*-aix4*
3329 ARM with RDP protocol arm-*-*
3330 I960 with MON960 i960-*-coff
3331 MIPS VxWorks mips*-*-vxworks*
3332 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3333 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3335 Matra Sparclet sparclet-*-*
3339 The powerpc-eabi configuration now includes the PSIM simulator,
3340 contributed by Andrew Cagney, with assistance from Mike Meissner.
3341 PSIM is a very elaborate model of the PowerPC, including not only
3342 basic instruction set execution, but also details of execution unit
3343 performance and I/O hardware. See sim/ppc/README for more details.
3347 GDB now works with Solaris 2.5.
3349 * Windows 95/NT native
3351 GDB will now work as a native debugger on Windows 95 and Windows NT.
3352 To build it from source, you must use the "gnu-win32" environment,
3353 which uses a DLL to emulate enough of Unix to run the GNU tools.
3354 Further information, binaries, and sources are available at
3355 ftp.cygnus.com, under pub/gnu-win32.
3357 * dont-repeat command
3359 If a user-defined command includes the command `dont-repeat', then the
3360 command will not be repeated if the user just types return. This is
3361 useful if the command is time-consuming to run, so that accidental
3362 extra keystrokes don't run the same command many times.
3364 * Send break instead of ^C
3366 The standard remote protocol now includes an option to send a break
3367 rather than a ^C to the target in order to interrupt it. By default,
3368 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3370 * Remote protocol timeout
3372 The standard remote protocol includes a new variable `remotetimeout'
3373 that allows you to set the number of seconds before GDB gives up trying
3374 to read from the target. The default value is 2.
3376 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3378 By default GDB will automatically keep track of objects as they are
3379 loaded and unloaded by the dynamic linker. By using the command `set
3380 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3381 when shared library events occur, thus allowing you to set breakpoints
3382 in shared libraries which are explicitly loaded by the inferior.
3384 Note this feature does not work on hpux8. On hpux9 you must link
3385 /usr/lib/end.o into your program. This feature should work
3386 automatically on hpux10.
3388 * Irix 5.x hardware watchpoint support
3390 Irix 5 configurations now support the use of hardware watchpoints.
3392 * Mips protocol "SYN garbage limit"
3394 When debugging a Mips target using the `target mips' protocol, you
3395 may set the number of characters that GDB will ignore by setting
3396 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3397 every character. The default value is 1050.
3399 * Recording and replaying remote debug sessions
3401 If you set `remotelogfile' to the name of a file, gdb will write to it
3402 a recording of a remote debug session. This recording may then be
3403 replayed back to gdb using "gdbreplay". See gdbserver/README for
3404 details. This is useful when you have a problem with GDB while doing
3405 remote debugging; you can make a recording of the session and send it
3406 to someone else, who can then recreate the problem.
3408 * Speedups for remote debugging
3410 GDB includes speedups for downloading and stepping MIPS systems using
3411 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3412 and more efficient S-record downloading.
3414 * Memory use reductions and statistics collection
3416 GDB now uses less memory and reports statistics about memory usage.
3417 Try the `maint print statistics' command, for example.
3419 *** Changes in GDB-4.15:
3421 * Psymtabs for XCOFF
3423 The symbol reader for AIX GDB now uses partial symbol tables. This
3424 can greatly improve startup time, especially for large executables.
3426 * Remote targets use caching
3428 Remote targets now use a data cache to speed up communication with the
3429 remote side. The data cache could lead to incorrect results because
3430 it doesn't know about volatile variables, thus making it impossible to
3431 debug targets which use memory mapped I/O devices. `set remotecache
3432 off' turns the the data cache off.
3434 * Remote targets may have threads
3436 The standard remote protocol now includes support for multiple threads
3437 in the target system, using new protocol commands 'H' and 'T'. See
3438 gdb/remote.c for details.
3442 If GDB is configured with `--enable-netrom', then it will include
3443 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3444 acts as though it is a bank of ROM on the target board, but you can
3445 write into it over the network. GDB's support consists only of
3446 support for fast loading into the emulated ROM; to debug, you must use
3447 another protocol, such as standard remote protocol. The usual
3448 sequence is something like
3450 target nrom <netrom-hostname>
3452 target remote <netrom-hostname>:1235
3456 GDB now includes support for the Apple Macintosh, as a host only. It
3457 may be run as either an MPW tool or as a standalone application, and
3458 it can debug through the serial port. All the usual GDB commands are
3459 available, but to the target command, you must supply "serial" as the
3460 device type instead of "/dev/ttyXX". See mpw-README in the main
3461 directory for more information on how to build. The MPW configuration
3462 scripts */mpw-config.in support only a few targets, and only the
3463 mips-idt-ecoff target has been tested.
3467 GDB configuration now uses autoconf. This is not user-visible,
3468 but does simplify configuration and building.
3472 GDB now supports hpux10.
3474 *** Changes in GDB-4.14:
3476 * New native configurations
3478 x86 FreeBSD i[345]86-*-freebsd
3479 x86 NetBSD i[345]86-*-netbsd
3480 NS32k NetBSD ns32k-*-netbsd
3481 Sparc NetBSD sparc-*-netbsd
3485 A29K VxWorks a29k-*-vxworks
3486 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3487 CPU32 EST-300 emulator m68*-*-est*
3488 PowerPC ELF powerpc-*-elf
3491 * Alpha OSF/1 support for procfs
3493 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3494 possible to attach to running processes. As the mounting of the /proc
3495 filesystem is optional on the Alpha, GDB automatically determines
3496 the availability of /proc during startup. This can lead to problems
3497 if /proc is unmounted after GDB has been started.
3499 * Arguments to user-defined commands
3501 User commands may accept up to 10 arguments separated by whitespace.
3502 Arguments are accessed within the user command via $arg0..$arg9. A
3505 print $arg0 + $arg1 + $arg2
3507 To execute the command use:
3510 Defines the command "adder" which prints the sum of its three arguments.
3511 Note the arguments are text substitutions, so they may reference variables,
3512 use complex expressions, or even perform inferior function calls.
3514 * New `if' and `while' commands
3516 This makes it possible to write more sophisticated user-defined
3517 commands. Both commands take a single argument, which is the
3518 expression to evaluate, and must be followed by the commands to
3519 execute, one per line, if the expression is nonzero, the list being
3520 terminated by the word `end'. The `if' command list may include an
3521 `else' word, which causes the following commands to be executed only
3522 if the expression is zero.
3524 * Fortran source language mode
3526 GDB now includes partial support for Fortran 77. It will recognize
3527 Fortran programs and can evaluate a subset of Fortran expressions, but
3528 variables and functions may not be handled correctly. GDB will work
3529 with G77, but does not yet know much about symbols emitted by other
3532 * Better HPUX support
3534 Most debugging facilities now work on dynamic executables for HPPAs
3535 running hpux9 or later. You can attach to running dynamically linked
3536 processes, but by default the dynamic libraries will be read-only, so
3537 for instance you won't be able to put breakpoints in them. To change
3538 that behavior do the following before running the program:
3544 This will cause the libraries to be mapped private and read-write.
3545 To revert to the normal behavior, do this:
3551 You cannot set breakpoints or examine data in the library until after
3552 the library is loaded if the function/data symbols do not have
3555 GDB can now also read debug symbols produced by the HP C compiler on
3556 HPPAs (sorry, no C++, Fortran or 68k support).
3558 * Target byte order now dynamically selectable
3560 You can choose which byte order to use with a target system, via the
3561 commands "set endian big" and "set endian little", and you can see the
3562 current setting by using "show endian". You can also give the command
3563 "set endian auto", in which case GDB will use the byte order
3564 associated with the executable. Currently, only embedded MIPS
3565 configurations support dynamic selection of target byte order.
3567 * New DOS host serial code
3569 This version uses DPMI interrupts to handle buffered I/O, so you
3570 no longer need to run asynctsr when debugging boards connected to
3573 *** Changes in GDB-4.13:
3575 * New "complete" command
3577 This lists all the possible completions for the rest of the line, if it
3578 were to be given as a command itself. This is intended for use by emacs.
3580 * Trailing space optional in prompt
3582 "set prompt" no longer adds a space for you after the prompt you set. This
3583 allows you to set a prompt which ends in a space or one that does not.
3585 * Breakpoint hit counts
3587 "info break" now displays a count of the number of times the breakpoint
3588 has been hit. This is especially useful in conjunction with "ignore"; you
3589 can ignore a large number of breakpoint hits, look at the breakpoint info
3590 to see how many times the breakpoint was hit, then run again, ignoring one
3591 less than that number, and this will get you quickly to the last hit of
3594 * Ability to stop printing at NULL character
3596 "set print null-stop" will cause GDB to stop printing the characters of
3597 an array when the first NULL is encountered. This is useful when large
3598 arrays actually contain only short strings.
3600 * Shared library breakpoints
3602 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3603 breakpoints in shared libraries before the executable is run.
3605 * Hardware watchpoints
3607 There is a new hardware breakpoint for the watch command for sparclite
3608 targets. See gdb/sparclite/hw_breakpoint.note.
3610 Hardware watchpoints are also now supported under GNU/Linux.
3614 Annotations have been added. These are for use with graphical interfaces,
3615 and are still experimental. Currently only gdba.el uses these.
3617 * Improved Irix 5 support
3619 GDB now works properly with Irix 5.2.
3621 * Improved HPPA support
3623 GDB now works properly with the latest GCC and GAS.
3625 * New native configurations
3627 Sequent PTX4 i[34]86-sequent-ptx4
3628 HPPA running OSF/1 hppa*-*-osf*
3629 Atari TT running SVR4 m68*-*-sysv4*
3630 RS/6000 LynxOS rs6000-*-lynxos*
3634 OS/9000 i[34]86-*-os9k
3635 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3638 * Hitachi SH7000 and E7000-PC ICE support
3640 There is now support for communicating with the Hitachi E7000-PC ICE.
3641 This is available automatically when GDB is configured for the SH.
3645 As usual, a variety of small fixes and improvements, both generic
3646 and configuration-specific. See the ChangeLog for more detail.
3648 *** Changes in GDB-4.12:
3650 * Irix 5 is now supported
3654 GDB-4.12 on the HPPA has a number of changes which make it unable
3655 to debug the output from the currently released versions of GCC and
3656 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3657 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3658 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3661 *** Changes in GDB-4.11:
3663 * User visible changes:
3667 The "set remotedebug" option is now consistent between the mips remote
3668 target, remote targets using the gdb-specific protocol, UDI (AMD's
3669 debug protocol for the 29k) and the 88k bug monitor. It is now an
3670 integer specifying a debug level (normally 0 or 1, but 2 means more
3671 debugging info for the mips target).
3673 * DEC Alpha native support
3675 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3676 debug info, but GDB works fairly well with the DEC compiler and should
3677 work with a future GCC release. See the README file for a few
3678 Alpha-specific notes.
3680 * Preliminary thread implementation
3682 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3684 * LynxOS native and target support for 386
3686 This release has been hosted on LynxOS 2.2, and also can be configured
3687 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3690 * Improvements in C++ mangling/demangling.
3692 This release has much better g++ debugging, specifically in name
3693 mangling/demangling, virtual function calls, print virtual table,
3694 call methods, ...etc.
3696 *** Changes in GDB-4.10:
3698 * User visible changes:
3700 Remote debugging using the GDB-specific (`target remote') protocol now
3701 supports the `load' command. This is only useful if you have some
3702 other way of getting the stub to the target system, and you can put it
3703 somewhere in memory where it won't get clobbered by the download.
3705 Filename completion now works.
3707 When run under emacs mode, the "info line" command now causes the
3708 arrow to point to the line specified. Also, "info line" prints
3709 addresses in symbolic form (as well as hex).
3711 All vxworks based targets now support a user settable option, called
3712 vxworks-timeout. This option represents the number of seconds gdb
3713 should wait for responses to rpc's. You might want to use this if
3714 your vxworks target is, perhaps, a slow software simulator or happens
3715 to be on the far side of a thin network line.
3719 This release contains support for using a DEC alpha as a GDB host for
3720 cross debugging. Native alpha debugging is not supported yet.
3723 *** Changes in GDB-4.9:
3727 This is the first GDB release which is accompanied by a matching testsuite.
3728 The testsuite requires installation of dejagnu, which should be available
3729 via ftp from most sites that carry GNU software.
3733 'Cfront' style demangling has had its name changed to 'ARM' style, to
3734 emphasize that it was written from the specifications in the C++ Annotated
3735 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3736 disclaimers, it still generated too much confusion with users attempting to
3737 use gdb with AT&T cfront.
3741 GDB now uses a standard remote interface to a simulator library.
3742 So far, the library contains simulators for the Zilog Z8001/2, the
3743 Hitachi H8/300, H8/500 and Super-H.
3745 * New targets supported
3747 H8/300 simulator h8300-hitachi-hms or h8300hms
3748 H8/500 simulator h8500-hitachi-hms or h8500hms
3749 SH simulator sh-hitachi-hms or sh
3750 Z8000 simulator z8k-zilog-none or z8ksim
3751 IDT MIPS board over serial line mips-idt-ecoff
3753 Cross-debugging to GO32 targets is supported. It requires a custom
3754 version of the i386-stub.c module which is integrated with the
3755 GO32 memory extender.
3757 * New remote protocols
3759 MIPS remote debugging protocol.
3761 * New source languages supported
3763 This version includes preliminary support for Chill, a Pascal like language
3764 used by telecommunications companies. Chill support is also being integrated
3765 into the GNU compiler, but we don't know when it will be publically available.
3768 *** Changes in GDB-4.8:
3770 * HP Precision Architecture supported
3772 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3773 version of this support was available as a set of patches from the
3774 University of Utah. GDB does not support debugging of programs
3775 compiled with the HP compiler, because HP will not document their file
3776 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3777 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3779 Many problems in the preliminary version have been fixed.
3781 * Faster and better demangling
3783 We have improved template demangling and fixed numerous bugs in the GNU style
3784 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3785 character types (wchar_t) are now supported. Demangling of each symbol is now
3786 only done once, and is cached when the symbol table for a file is read in.
3787 This results in a small increase in memory usage for C programs, a moderate
3788 increase in memory usage for C++ programs, and a fantastic speedup in
3791 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3792 from the specifications in the Annotated Reference Manual, which AT&T's
3793 compiler does not actually implement.
3795 * G++ multiple inheritance compiler problem
3797 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3798 inheritance lattices was reworked to properly discover ambiguities. We
3799 recently found an example which causes this new algorithm to fail in a
3800 very subtle way, producing bad debug information for those classes.
3801 The file 'gcc.patch' (in this directory) can be applied to gcc to
3802 circumvent the problem. A future GCC release will contain a complete
3805 The previous G++ debug info problem (mentioned below for the gdb-4.7
3806 release) is fixed in gcc version 2.3.2.
3808 * Improved configure script
3810 The `configure' script will now attempt to guess your system type if
3811 you don't supply a host system type. The old scheme of supplying a
3812 host system triplet is preferable over using this. All the magic is
3813 done in the new `config.guess' script. Examine it for details.
3815 We have also brought our configure script much more in line with the FSF's
3816 version. It now supports the --with-xxx options. In particular,
3817 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3818 The resulting GDB will not be able to read arbitrary object file formats --
3819 only the format ``expected'' to be used on the configured target system.
3820 We hope to make this the default in a future release.
3822 * Documentation improvements
3824 There's new internal documentation on how to modify GDB, and how to
3825 produce clean changes to the code. We implore people to read it
3826 before submitting changes.
3828 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3829 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3830 `info' files are also provided. To build `info' files from scratch,
3831 you will need the latest `makeinfo' release, which will be available in
3832 a future texinfo-X.Y release.
3834 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3835 We're not sure exactly which versions have this problem, but it has
3836 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3837 or better. If that isn't possible, there is a patch in
3838 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3839 around this problem.
3843 GDB now supports array constants that can be used in expressions typed in by
3844 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3845 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3848 The new directory `gdb/sparclite' contains a program that demonstrates
3849 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3851 * New native hosts supported
3853 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3854 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3856 * New targets supported
3858 AMD 29k family via UDI a29k-amd-udi or udi29k
3860 * New file formats supported
3862 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3863 HPUX core files, and SCO 3.2v2 core files.
3867 Attaching to processes now works again; thanks for the many bug reports.
3869 We have also stomped on a bunch of core dumps caused by
3870 printf_filtered("%s") problems.
3872 We eliminated a copyright problem on the rpc and ptrace header files
3873 for VxWorks, which was discovered at the last minute during the 4.7
3874 release. You should now be able to build a VxWorks GDB.
3876 You can now interrupt gdb while an attached process is running. This
3877 will cause the attached process to stop, and give control back to GDB.
3879 We fixed problems caused by using too many file descriptors
3880 for reading symbols from object files and libraries. This was
3881 especially a problem for programs that used many (~100) shared
3884 The `step' command now only enters a subroutine if there is line number
3885 information for the subroutine. Otherwise it acts like the `next'
3886 command. Previously, `step' would enter subroutines if there was
3887 any debugging information about the routine. This avoids problems
3888 when using `cc -g1' on MIPS machines.
3890 * Internal improvements
3892 GDB's internal interfaces have been improved to make it easier to support
3893 debugging of multiple languages in the future.
3895 GDB now uses a common structure for symbol information internally.
3896 Minimal symbols (derived from linkage symbols in object files), partial
3897 symbols (from a quick scan of debug information), and full symbols
3898 contain a common subset of information, making it easier to write
3899 shared code that handles any of them.
3901 * New command line options
3903 We now accept --silent as an alias for --quiet.
3907 The memory-mapped-malloc library is now licensed under the GNU Library
3908 General Public License.
3910 *** Changes in GDB-4.7:
3912 * Host/native/target split
3914 GDB has had some major internal surgery to untangle the support for
3915 hosts and remote targets. Now, when you configure GDB for a remote
3916 target, it will no longer load in all of the support for debugging
3917 local programs on the host. When fully completed and tested, this will
3918 ensure that arbitrary host/target combinations are possible.
3920 The primary conceptual shift is to separate the non-portable code in
3921 GDB into three categories. Host specific code is required any time GDB
3922 is compiled on that host, regardless of the target. Target specific
3923 code relates to the peculiarities of the target, but can be compiled on
3924 any host. Native specific code is everything else: it can only be
3925 built when the host and target are the same system. Child process
3926 handling and core file support are two common `native' examples.
3928 GDB's use of /proc for controlling Unix child processes is now cleaner.
3929 It has been split out into a single module under the `target_ops' vector,
3930 plus two native-dependent functions for each system that uses /proc.
3932 * New hosts supported
3934 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3935 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3936 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3938 * New targets supported
3940 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3941 68030 and CPU32 m68030-*-*, m68332-*-*
3943 * New native hosts supported
3945 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3946 (386bsd is not well tested yet)
3947 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3949 * New file formats supported
3951 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3952 supports reading of `a.out.adobe' object files, which are an a.out
3953 format extended with minimal information about multiple sections.
3957 `show copying' is the same as the old `info copying'.
3958 `show warranty' is the same as `info warrantee'.
3959 These were renamed for consistency. The old commands continue to work.
3961 `info handle' is a new alias for `info signals'.
3963 You can now define pre-command hooks, which attach arbitrary command
3964 scripts to any command. The commands in the hook will be executed
3965 prior to the user's command. You can also create a hook which will be
3966 executed whenever the program stops. See gdb.texinfo.
3970 We now deal with Cfront style name mangling, and can even extract type
3971 info from mangled symbols. GDB can automatically figure out which
3972 symbol mangling style your C++ compiler uses.
3974 Calling of methods and virtual functions has been improved as well.
3978 The crash that occured when debugging Sun Ansi-C compiled binaries is
3979 fixed. This was due to mishandling of the extra N_SO stabs output
3982 We also finally got Ultrix 4.2 running in house, and fixed core file
3983 support, with help from a dozen people on the net.
3985 John M. Farrell discovered that the reason that single-stepping was so
3986 slow on all of the Mips based platforms (primarily SGI and DEC) was
3987 that we were trying to demangle and lookup a symbol used for internal
3988 purposes on every instruction that was being stepped through. Changing
3989 the name of that symbol so that it couldn't be mistaken for a C++
3990 mangled symbol sped things up a great deal.
3992 Rich Pixley sped up symbol lookups in general by getting much smarter
3993 about when C++ symbol mangling is necessary. This should make symbol
3994 completion (TAB on the command line) much faster. It's not as fast as
3995 we'd like, but it's significantly faster than gdb-4.6.
3999 A new user controllable variable 'call_scratch_address' can
4000 specify the location of a scratch area to be used when GDB
4001 calls a function in the target. This is necessary because the
4002 usual method of putting the scratch area on the stack does not work
4003 in systems that have separate instruction and data spaces.
4005 We integrated changes to support the 29k UDI (Universal Debugger
4006 Interface), but discovered at the last minute that we didn't have all
4007 of the appropriate copyright paperwork. We are working with AMD to
4008 resolve this, and hope to have it available soon.
4012 We have sped up the remote serial line protocol, especially for targets
4013 with lots of registers. It now supports a new `expedited status' ('T')
4014 message which can be used in place of the existing 'S' status message.
4015 This allows the remote stub to send only the registers that GDB
4016 needs to make a quick decision about single-stepping or conditional
4017 breakpoints, eliminating the need to fetch the entire register set for
4018 each instruction being stepped through.
4020 The GDB remote serial protocol now implements a write-through cache for
4021 registers, only re-reading the registers if the target has run.
4023 There is also a new remote serial stub for SPARC processors. You can
4024 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4025 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4026 processor with a serial port.
4030 Configure.in files have become much easier to read and modify. A new
4031 `table driven' format makes it more obvious what configurations are
4032 supported, and what files each one uses.
4036 There is a new opcodes library which will eventually contain all of the
4037 disassembly routines and opcode tables. At present, it only contains
4038 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4039 disassembler (binutils/objdump) to share these routines.
4041 The libiberty library is now copylefted under the GNU Library General
4042 Public License. This allows more liberal use, and was done so libg++
4043 can use it. This makes no difference to GDB, since the Library License
4044 grants all the rights from the General Public License.
4048 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4049 reference to the stabs symbol info used by the debugger. It is (as far
4050 as we know) the only published document on this fascinating topic. We
4051 encourage you to read it, compare it to the stabs information on your
4052 system, and send improvements on the document in general (to
4053 bug-gdb@prep.ai.mit.edu).
4055 And, of course, many bugs have been fixed.
4058 *** Changes in GDB-4.6:
4060 * Better support for C++ function names
4062 GDB now accepts as input the "demangled form" of C++ overloaded function
4063 names and member function names, and can do command completion on such names
4064 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4065 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4066 Make use of command completion, it is your friend.
4068 GDB also now accepts a variety of C++ mangled symbol formats. They are
4069 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4070 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4071 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4072 for the list of formats.
4074 * G++ symbol mangling problem
4076 Recent versions of gcc have a bug in how they emit debugging information for
4077 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4078 directory) can be applied to gcc to fix the problem. Alternatively, if you
4079 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4080 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4081 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4084 * New 'maintenance' command
4086 All of the commands related to hacking GDB internals have been moved out of
4087 the main command set, and now live behind the 'maintenance' command. This
4088 can also be abbreviated as 'mt'. The following changes were made:
4090 dump-me -> maintenance dump-me
4091 info all-breakpoints -> maintenance info breakpoints
4092 printmsyms -> maintenance print msyms
4093 printobjfiles -> maintenance print objfiles
4094 printpsyms -> maintenance print psymbols
4095 printsyms -> maintenance print symbols
4097 The following commands are new:
4099 maintenance demangle Call internal GDB demangler routine to
4100 demangle a C++ link name and prints the result.
4101 maintenance print type Print a type chain for a given symbol
4103 * Change to .gdbinit file processing
4105 We now read the $HOME/.gdbinit file before processing the argv arguments
4106 (e.g. reading symbol files or core files). This allows global parameters to
4107 be set, which will apply during the symbol reading. The ./.gdbinit is still
4108 read after argv processing.
4110 * New hosts supported
4112 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4114 GNU/Linux support i386-unknown-linux or linux
4116 We are also including code to support the HP/PA running BSD and HPUX. This
4117 is almost guaranteed not to work, as we didn't have time to test or build it
4118 for this release. We are including it so that the more adventurous (or
4119 masochistic) of you can play with it. We also had major problems with the
4120 fact that the compiler that we got from HP doesn't support the -g option.
4123 * New targets supported
4125 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4127 * More smarts about finding #include files
4129 GDB now remembers the compilation directory for all include files, and for
4130 all files from which C is generated (like yacc and lex sources). This
4131 greatly improves GDB's ability to find yacc/lex sources, and include files,
4132 especially if you are debugging your program from a directory different from
4133 the one that contains your sources.
4135 We also fixed a bug which caused difficulty with listing and setting
4136 breakpoints in include files which contain C code. (In the past, you had to
4137 try twice in order to list an include file that you hadn't looked at before.)
4139 * Interesting infernals change
4141 GDB now deals with arbitrary numbers of sections, where the symbols for each
4142 section must be relocated relative to that section's landing place in the
4143 target's address space. This work was needed to support ELF with embedded
4144 stabs used by Solaris-2.0.
4146 * Bug fixes (of course!)
4148 There have been loads of fixes for the following things:
4149 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4150 i960, stabs, DOS(GO32), procfs, etc...
4152 See the ChangeLog for details.
4154 *** Changes in GDB-4.5:
4156 * New machines supported (host and target)
4158 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4160 SGI Irix-4.x mips-sgi-irix4 or iris4
4162 * New malloc package
4164 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4165 Mmalloc is capable of handling mutiple heaps of memory. It is also
4166 capable of saving a heap to a file, and then mapping it back in later.
4167 This can be used to greatly speedup the startup of GDB by using a
4168 pre-parsed symbol table which lives in a mmalloc managed heap. For
4169 more details, please read mmalloc/mmalloc.texi.
4173 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4174 'help info proc' for details.
4176 * MIPS ecoff symbol table format
4178 The code that reads MIPS symbol table format is now supported on all hosts.
4179 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4182 * File name changes for MS-DOS
4184 Many files in the config directories have been renamed to make it easier to
4185 support GDB on MS-DOSe systems (which have very restrictive file name
4186 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4187 environment) is close to working but has some remaining problems. Note
4188 that debugging of DOS programs is not supported, due to limitations
4189 in the ``operating system'', but it can be used to host cross-debugging.
4191 * Cross byte order fixes
4193 Many fixes have been made to support cross debugging of Sparc and MIPS
4194 targets from hosts whose byte order differs.
4196 * New -mapped and -readnow options
4198 If memory-mapped files are available on your system through the 'mmap'
4199 system call, you can use the -mapped option on the `file' or
4200 `symbol-file' commands to cause GDB to write the symbols from your
4201 program into a reusable file. If the program you are debugging is
4202 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4203 Future GDB debugging sessions will notice the presence of this file,
4204 and will quickly map in symbol information from it, rather than reading
4205 the symbol table from the executable program. Using the '-mapped'
4206 option in a GDB `file' or `symbol-file' command has the same effect as
4207 starting GDB with the '-mapped' command-line option.
4209 You can cause GDB to read the entire symbol table immediately by using
4210 the '-readnow' option with any of the commands that load symbol table
4211 information (or on the GDB command line). This makes the command
4212 slower, but makes future operations faster.
4214 The -mapped and -readnow options are typically combined in order to
4215 build a `fred.syms' file that contains complete symbol information.
4216 A simple GDB invocation to do nothing but build a `.syms' file for future
4219 gdb -batch -nx -mapped -readnow programname
4221 The `.syms' file is specific to the host machine on which GDB is run.
4222 It holds an exact image of GDB's internal symbol table. It cannot be
4223 shared across multiple host platforms.
4225 * longjmp() handling
4227 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4228 siglongjmp() without losing control. This feature has not yet been ported to
4229 all systems. It currently works on many 386 platforms, all MIPS-based
4230 platforms (SGI, DECstation, etc), and Sun3/4.
4234 Preliminary work has been put in to support the new Solaris OS from Sun. At
4235 this time, it can control and debug processes, but it is not capable of
4240 As always, many many bug fixes. The major areas were with g++, and mipsread.
4241 People using the MIPS-based platforms should experience fewer mysterious
4242 crashes and trashed symbol tables.
4244 *** Changes in GDB-4.4:
4246 * New machines supported (host and target)
4248 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4250 BSD Reno on Vax vax-dec-bsd
4251 Ultrix on Vax vax-dec-ultrix
4253 * New machines supported (target)
4255 AMD 29000 embedded, using EBMON a29k-none-none
4259 GDB continues to improve its handling of C++. `References' work better.
4260 The demangler has also been improved, and now deals with symbols mangled as
4261 per the Annotated C++ Reference Guide.
4263 GDB also now handles `stabs' symbol information embedded in MIPS
4264 `ecoff' symbol tables. Since the ecoff format was not easily
4265 extensible to handle new languages such as C++, this appeared to be a
4266 good way to put C++ debugging info into MIPS binaries. This option
4267 will be supported in the GNU C compiler, version 2, when it is
4270 * New features for SVR4
4272 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4273 shared libraries. Debugging dynamically linked programs should present
4274 only minor differences from debugging statically linked programs.
4276 The `info proc' command will print out information about any process
4277 on an SVR4 system (including the one you are debugging). At the moment,
4278 it prints the address mappings of the process.
4280 If you bring up GDB on another SVR4 system, please send mail to
4281 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4283 * Better dynamic linking support in SunOS
4285 Reading symbols from shared libraries which contain debugging symbols
4286 now works properly. However, there remain issues such as automatic
4287 skipping of `transfer vector' code during function calls, which
4288 make it harder to debug code in a shared library, than to debug the
4289 same code linked statically.
4293 GDB is now using the latest `getopt' routines from the FSF. This
4294 version accepts the -- prefix for options with long names. GDB will
4295 continue to accept the old forms (-option and +option) as well.
4296 Various single letter abbreviations for options have been explicity
4297 added to the option table so that they won't get overshadowed in the
4298 future by other options that begin with the same letter.
4302 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4303 Many assorted bugs have been handled. Many more remain to be handled.
4304 See the various ChangeLog files (primarily in gdb and bfd) for details.
4307 *** Changes in GDB-4.3:
4309 * New machines supported (host and target)
4311 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4312 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4313 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4315 * Almost SCO Unix support
4317 We had hoped to support:
4318 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4319 (except for core file support), but we discovered very late in the release
4320 that it has problems with process groups that render gdb unusable. Sorry
4321 about that. I encourage people to fix it and post the fixes.
4323 * Preliminary ELF and DWARF support
4325 GDB can read ELF object files on System V Release 4, and can handle
4326 debugging records for C, in DWARF format, in ELF files. This support
4327 is preliminary. If you bring up GDB on another SVR4 system, please
4328 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4333 GDB now uses the latest `readline' library. One user-visible change
4334 is that two tabs will list possible command completions, which previously
4335 required typing M-? (meta-question mark, or ESC ?).
4339 The `stepi' bug that many of you noticed has been squashed.
4340 Many bugs in C++ have been handled. Many more remain to be handled.
4341 See the various ChangeLog files (primarily in gdb and bfd) for details.
4343 * State of the MIPS world (in case you wondered):
4345 GDB can understand the symbol tables emitted by the compilers
4346 supplied by most vendors of MIPS-based machines, including DEC. These
4347 symbol tables are in a format that essentially nobody else uses.
4349 Some versions of gcc come with an assembler post-processor called
4350 mips-tfile. This program is required if you want to do source-level
4351 debugging of gcc-compiled programs. I believe FSF does not ship
4352 mips-tfile with gcc version 1, but it will eventually come with gcc
4355 Debugging of g++ output remains a problem. g++ version 1.xx does not
4356 really support it at all. (If you're lucky, you should be able to get
4357 line numbers and stack traces to work, but no parameters or local
4358 variables.) With some work it should be possible to improve the
4361 When gcc version 2 is released, you will have somewhat better luck.
4362 However, even then you will get confusing results for inheritance and
4365 We will eventually provide full debugging of g++ output on
4366 DECstations. This will probably involve some kind of stabs-in-ecoff
4367 encapulation, but the details have not been worked out yet.
4370 *** Changes in GDB-4.2:
4372 * Improved configuration
4374 Only one copy of `configure' exists now, and it is not self-modifying.
4375 Porting BFD is simpler.
4379 The `step' and `next' commands now only stop at the first instruction
4380 of a source line. This prevents the multiple stops that used to occur
4381 in switch statements, for-loops, etc. `Step' continues to stop if a
4382 function that has debugging information is called within the line.
4386 Lots of small bugs fixed. More remain.
4388 * New host supported (not target)
4390 Intel 386 PC clone running Mach i386-none-mach
4393 *** Changes in GDB-4.1:
4395 * Multiple source language support
4397 GDB now has internal scaffolding to handle several source languages.
4398 It determines the type of each source file from its filename extension,
4399 and will switch expression parsing and number formatting to match the
4400 language of the function in the currently selected stack frame.
4401 You can also specifically set the language to be used, with
4402 `set language c' or `set language modula-2'.
4406 GDB now has preliminary support for the GNU Modula-2 compiler,
4407 currently under development at the State University of New York at
4408 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4409 continue through the fall of 1991 and into 1992.
4411 Other Modula-2 compilers are currently not supported, and attempting to
4412 debug programs compiled with them will likely result in an error as the
4413 symbol table is read. Feel free to work on it, though!
4415 There are hooks in GDB for strict type checking and range checking,
4416 in the `Modula-2 philosophy', but they do not currently work.
4420 GDB can now write to executable and core files (e.g. patch
4421 a variable's value). You must turn this switch on, specify
4422 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4423 by assigning a new value to a variable. Modifications take
4426 * Automatic SunOS shared library reading
4428 When you run your program, GDB automatically determines where its
4429 shared libraries (if any) have been loaded, and reads their symbols.
4430 The `share' command is no longer needed. This also works when
4431 examining core files.
4435 You can specify the number of lines that the `list' command shows.
4438 * New machines supported (host and target)
4440 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4441 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4442 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4444 * New hosts supported (not targets)
4446 IBM RT/PC: romp-ibm-aix or rtpc
4448 * New targets supported (not hosts)
4450 AMD 29000 embedded with COFF a29k-none-coff
4451 AMD 29000 embedded with a.out a29k-none-aout
4452 Ultracomputer remote kernel debug a29k-nyu-kern
4454 * New remote interfaces
4460 *** Changes in GDB-4.0:
4464 Wide output is wrapped at good places to make the output more readable.
4466 Gdb now supports cross-debugging from a host machine of one type to a
4467 target machine of another type. Communication with the target system
4468 is over serial lines. The ``target'' command handles connecting to the
4469 remote system; the ``load'' command will download a program into the
4470 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4471 also supports debugging of realtime processes running under VxWorks,
4472 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4473 stub on the target system.
4475 New CPUs supported include the AMD 29000 and Intel 960.
4477 GDB now reads object files and symbol tables via a ``binary file''
4478 library, which allows a single copy of GDB to debug programs of multiple
4479 object file types such as a.out and coff.
4481 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4482 refcard.dvi and refcard.ps are available to format it).
4485 * Control-Variable user interface simplified
4487 All variables that control the operation of the debugger can be set
4488 by the ``set'' command, and displayed by the ``show'' command.
4490 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4491 ``Show prompt'' produces the response:
4492 Gdb's prompt is new-gdb=>.
4494 What follows are the NEW set commands. The command ``help set'' will
4495 print a complete list of old and new set commands. ``help set FOO''
4496 will give a longer description of the variable FOO. ``show'' will show
4497 all of the variable descriptions and their current settings.
4499 confirm on/off: Enables warning questions for operations that are
4500 hard to recover from, e.g. rerunning the program while
4501 it is already running. Default is ON.
4503 editing on/off: Enables EMACS style command line editing
4504 of input. Previous lines can be recalled with
4505 control-P, the current line can be edited with control-B,
4506 you can search for commands with control-R, etc.
4509 history filename NAME: NAME is where the gdb command history
4510 will be stored. The default is .gdb_history,
4511 or the value of the environment variable
4514 history size N: The size, in commands, of the command history. The
4515 default is 256, or the value of the environment variable
4518 history save on/off: If this value is set to ON, the history file will
4519 be saved after exiting gdb. If set to OFF, the
4520 file will not be saved. The default is OFF.
4522 history expansion on/off: If this value is set to ON, then csh-like
4523 history expansion will be performed on
4524 command line input. The default is OFF.
4526 radix N: Sets the default radix for input and output. It can be set
4527 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4528 in the current radix, so "set radix 10" is always a no-op.
4530 height N: This integer value is the number of lines on a page. Default
4531 is 24, the current `stty rows'' setting, or the ``li#''
4532 setting from the termcap entry matching the environment
4535 width N: This integer value is the number of characters on a line.
4536 Default is 80, the current `stty cols'' setting, or the ``co#''
4537 setting from the termcap entry matching the environment
4540 Note: ``set screensize'' is obsolete. Use ``set height'' and
4541 ``set width'' instead.
4543 print address on/off: Print memory addresses in various command displays,
4544 such as stack traces and structure values. Gdb looks
4545 more ``symbolic'' if you turn this off; it looks more
4546 ``machine level'' with it on. Default is ON.
4548 print array on/off: Prettyprint arrays. New convenient format! Default
4551 print demangle on/off: Print C++ symbols in "source" form if on,
4554 print asm-demangle on/off: Same, for assembler level printouts
4557 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4560 * Support for Epoch Environment.
4562 The epoch environment is a version of Emacs v18 with windowing. One
4563 new command, ``inspect'', is identical to ``print'', except that if you
4564 are running in the epoch environment, the value is printed in its own
4568 * Support for Shared Libraries
4570 GDB can now debug programs and core files that use SunOS shared libraries.
4571 Symbols from a shared library cannot be referenced
4572 before the shared library has been linked with the program (this
4573 happens after you type ``run'' and before the function main() is entered).
4574 At any time after this linking (including when examining core files
4575 from dynamically linked programs), gdb reads the symbols from each
4576 shared library when you type the ``sharedlibrary'' command.
4577 It can be abbreviated ``share''.
4579 sharedlibrary REGEXP: Load shared object library symbols for files
4580 matching a unix regular expression. No argument
4581 indicates to load symbols for all shared libraries.
4583 info sharedlibrary: Status of loaded shared libraries.
4588 A watchpoint stops execution of a program whenever the value of an
4589 expression changes. Checking for this slows down execution
4590 tremendously whenever you are in the scope of the expression, but is
4591 quite useful for catching tough ``bit-spreader'' or pointer misuse
4592 problems. Some machines such as the 386 have hardware for doing this
4593 more quickly, and future versions of gdb will use this hardware.
4595 watch EXP: Set a watchpoint (breakpoint) for an expression.
4597 info watchpoints: Information about your watchpoints.
4599 delete N: Deletes watchpoint number N (same as breakpoints).
4600 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4601 enable N: Re-enables watchpoint number N (same as breakpoints).
4604 * C++ multiple inheritance
4606 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4609 * C++ exception handling
4611 Gdb now supports limited C++ exception handling. Besides the existing
4612 ability to breakpoint on an exception handler, gdb can breakpoint on
4613 the raising of an exception (before the stack is peeled back to the
4616 catch FOO: If there is a FOO exception handler in the dynamic scope,
4617 set a breakpoint to catch exceptions which may be raised there.
4618 Multiple exceptions (``catch foo bar baz'') may be caught.
4620 info catch: Lists all exceptions which may be caught in the
4621 current stack frame.
4624 * Minor command changes
4626 The command ``call func (arg, arg, ...)'' now acts like the print
4627 command, except it does not print or save a value if the function's result
4628 is void. This is similar to dbx usage.
4630 The ``up'' and ``down'' commands now always print the frame they end up
4631 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4632 frames without printing.
4634 * New directory command
4636 'dir' now adds directories to the FRONT of the source search path.
4637 The path starts off empty. Source files that contain debug information
4638 about the directory in which they were compiled can be found even
4639 with an empty path; Sun CC and GCC include this information. If GDB can't
4640 find your source file in the current directory, type "dir .".
4642 * Configuring GDB for compilation
4644 For normal use, type ``./configure host''. See README or gdb.texinfo
4647 GDB now handles cross debugging. If you are remotely debugging between
4648 two different machines, type ``./configure host -target=targ''.
4649 Host is the machine where GDB will run; targ is the machine
4650 where the program that you are debugging will run.