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 "maint set python print-stack on|off" command has been
19 deprecated, and a new command: "set python print-stack on|off" has
20 replaced it. Additionally, the default for "print-stack" is now
23 ** A prompt subsitution hook (prompt_hook) is now available to the
26 ** A new command set/show extended-prompt has been added.
28 ** A new Python module, gdb.prompt has been added to the GDB Python
29 modules library. This module provides functionality for
30 escape sequentions in prompts (used by set/show
31 extended-prompt). These escape sequences are replaced by their
34 ** Python commands and convenience-functions located in
35 'data-directory'/python/gdb/command and
36 'data-directory'/python/gdb/function are now automatically loaded
39 ** Symbols now provide the "type" attribute, the type of the symbol.
41 ** The "gdb.breakpoint" function has been deprecated in favor of
44 * libthread-db-search-path now supports two special values: $sdir and $pdir.
45 $sdir specifies the default system locations of shared libraries.
46 $pdir specifies the directory where the libpthread used by the application
49 GDB no longer looks in $sdir and $pdir after it has searched the directories
50 mentioned in libthread-db-search-path. If you want to search those
51 directories, they must be specified in libthread-db-search-path.
52 The default value of libthread-db-search-path on GNU/Linux and Solaris
53 systems is now "$sdir:$pdir".
55 $pdir is not supported by gdbserver, it is currently ignored.
56 $sdir is supported by gdbserver.
58 * New configure option --with-iconv-bin.
59 When using the internationalization support like the one in the GNU C
60 library, GDB will invoke the "iconv" program to get a list of supported
61 character sets. If this program lives in a non-standard location, one can
62 use this option to specify where to find it.
64 * When natively debugging programs on PowerPC BookE processors running
65 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
66 watchpoints, which specify a mask in addition to an address to watch.
67 The mask specifies that some bits of an address (the bits which are
68 reset in the mask) should be ignored when matching the address accessed
69 by the inferior against the watchpoint address. See the "PowerPC Embedded"
70 section in the user manual for more details.
72 * The new option --once causes GDBserver to stop listening for connections once
73 the first connection is made. The listening port used by GDBserver will
74 become available after that.
76 * New commands "info macros", and "info definitions" have been added.
80 watch EXPRESSION mask MASK_VALUE
81 The watch command now supports the mask argument which allows creation
82 of masked watchpoints, if the current architecture supports this feature.
84 info auto-load-scripts [REGEXP]
85 This command was formerly named "maintenance print section-scripts".
86 It is now generally useful and is no longer a maintenance-only command.
88 * Tracepoints can now be enabled and disabled at any time after a trace
89 experiment has been started using the standard "enable" and "disable"
90 commands. It is now possible to start a trace experiment with no enabled
91 tracepoints; GDB will display a warning, but will allow the experiment to
92 begin, assuming that tracepoints will be enabled as needed while the trace
99 Dynamically enable a tracepoint in a started trace experiment.
103 Dynamically disable a tracepoint in a started trace experiment.
105 * Dcache size (number of lines) and line-size are now runtime-configurable
106 via "set dcache line" and "set dcache line-size" commands.
110 Texas Instruments TMS320C6x tic6x-*-*
112 *** Changes in GDB 7.3.1
114 * The build failure for NetBSD and OpenBSD targets have now been fixed.
116 *** Changes in GDB 7.3
118 * GDB has a new command: "thread find [REGEXP]".
119 It finds the thread id whose name, target id, or thread extra info
120 matches the given regular expression.
122 * The "catch syscall" command now works on mips*-linux* targets.
124 * The -data-disassemble MI command now supports modes 2 and 3 for
125 dumping the instruction opcodes.
127 * New command line options
129 -data-directory DIR Specify DIR as the "data-directory".
130 This is mostly for testing purposes.
132 * The "maint set python auto-load on|off" command has been renamed to
133 "set auto-load-scripts on|off".
135 * GDB has a new command: "set directories".
136 It is like the "dir" command except that it replaces the
137 source path list instead of augmenting it.
139 * GDB now understands thread names.
141 On GNU/Linux, "info threads" will display the thread name as set by
142 prctl or pthread_setname_np.
144 There is also a new command, "thread name", which can be used to
145 assign a name internally for GDB to display.
148 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
149 has been integrated into GDB.
153 ** The function gdb.Write now accepts an optional keyword 'stream'.
154 This keyword, when provided, will direct the output to either
155 stdout, stderr, or GDB's logging output.
157 ** Parameters can now be be sub-classed in Python, and in particular
158 you may implement the get_set_doc and get_show_doc functions.
159 This improves how Parameter set/show documentation is processed
160 and allows for more dynamic content.
162 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
163 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
164 have an is_valid method.
166 ** Breakpoints can now be sub-classed in Python, and in particular
167 you may implement a 'stop' function that is executed each time
168 the inferior reaches that breakpoint.
170 ** New function gdb.lookup_global_symbol looks up a global symbol.
172 ** GDB values in Python are now callable if the value represents a
173 function. For example, if 'some_value' represents a function that
174 takes two integer parameters and returns a value, you can call
175 that function like so:
177 result = some_value (10,20)
179 ** Module gdb.types has been added.
180 It contains a collection of utilities for working with gdb.Types objects:
181 get_basic_type, has_field, make_enum_dict.
183 ** Module gdb.printing has been added.
184 It contains utilities for writing and registering pretty-printers.
185 New classes: PrettyPrinter, SubPrettyPrinter,
186 RegexpCollectionPrettyPrinter.
187 New function: register_pretty_printer.
189 ** New commands "info pretty-printers", "enable pretty-printer" and
190 "disable pretty-printer" have been added.
192 ** gdb.parameter("directories") is now available.
194 ** New function gdb.newest_frame returns the newest frame in the
197 ** The gdb.InferiorThread class has a new "name" attribute. This
198 holds the thread's name.
200 ** Python Support for Inferior events.
201 Python scripts can add observers to be notified of events
202 occurring in the process being debugged.
203 The following events are currently supported:
204 - gdb.events.cont Continue event.
205 - gdb.events.exited Inferior exited event.
206 - gdb.events.stop Signal received, and Breakpoint hit events.
210 ** GDB now puts template parameters in scope when debugging in an
211 instantiation. For example, if you have:
213 template<int X> int func (void) { return X; }
215 then if you step into func<5>, "print X" will show "5". This
216 feature requires proper debuginfo support from the compiler; it
217 was added to GCC 4.5.
219 ** The motion commands "next", "finish", "until", and "advance" now
220 work better when exceptions are thrown. In particular, GDB will
221 no longer lose control of the inferior; instead, the GDB will
222 stop the inferior at the point at which the exception is caught.
223 This functionality requires a change in the exception handling
224 code that was introduced in GCC 4.5.
226 * GDB now follows GCC's rules on accessing volatile objects when
227 reading or writing target state during expression evaluation.
228 One notable difference to prior behavior is that "print x = 0"
229 no longer generates a read of x; the value of the assignment is
230 now always taken directly from the value being assigned.
232 * GDB now has some support for using labels in the program's source in
233 linespecs. For instance, you can use "advance label" to continue
234 execution to a label.
236 * GDB now has support for reading and writing a new .gdb_index
237 section. This section holds a fast index of DWARF debugging
238 information and can be used to greatly speed up GDB startup and
239 operation. See the documentation for `save gdb-index' for details.
241 * The "watch" command now accepts an optional "-location" argument.
242 When used, this causes GDB to watch the memory referred to by the
243 expression. Such a watchpoint is never deleted due to it going out
246 * GDB now supports thread debugging of core dumps on GNU/Linux.
248 GDB now activates thread debugging using the libthread_db library
249 when debugging GNU/Linux core dumps, similarly to when debugging
250 live processes. As a result, when debugging a core dump file, GDB
251 is now able to display pthread_t ids of threads. For example, "info
252 threads" shows the same output as when debugging the process when it
253 was live. In earlier releases, you'd see something like this:
256 * 1 LWP 6780 main () at main.c:10
258 While now you see this:
261 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
263 It is also now possible to inspect TLS variables when debugging core
266 When debugging a core dump generated on a machine other than the one
267 used to run GDB, you may need to point GDB at the correct
268 libthread_db library with the "set libthread-db-search-path"
269 command. See the user manual for more details on this command.
271 * When natively debugging programs on PowerPC BookE processors running
272 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
273 which stop execution of the inferior whenever it executes an instruction
274 at any address within the specified range. See the "PowerPC Embedded"
275 section in the user manual for more details.
277 * New features in the GDB remote stub, GDBserver
279 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
280 and i686 LynxOS (version 5.x).
282 ** GDBserver is now supported on Blackfin Linux.
284 * New native configurations
286 ia64 HP-UX ia64-*-hpux*
290 Analog Devices, Inc. Blackfin Processor bfin-*
292 * Ada task switching is now supported on sparc-elf targets when
293 debugging a program using the Ravenscar Profile. For more information,
294 see the "Tasking Support when using the Ravenscar Profile" section
295 in the GDB user manual.
297 * Guile support was removed.
299 * New features in the GNU simulator
301 ** The --map-info flag lists all known core mappings.
303 ** CFI flashes may be simulated via the "cfi" device.
305 *** Changes in GDB 7.2
307 * Shared library support for remote targets by default
309 When GDB is configured for a generic, non-OS specific target, like
310 for example, --target=arm-eabi or one of the many *-*-elf targets,
311 GDB now queries remote stubs for loaded shared libraries using the
312 `qXfer:libraries:read' packet. Previously, shared library support
313 was always disabled for such configurations.
317 ** Argument Dependent Lookup (ADL)
319 In C++ ADL lookup directs function search to the namespaces of its
320 arguments even if the namespace has not been imported.
330 Here the compiler will search for `foo' in the namespace of 'b'
331 and find A::foo. GDB now supports this. This construct is commonly
332 used in the Standard Template Library for operators.
334 ** Improved User Defined Operator Support
336 In addition to member operators, GDB now supports lookup of operators
337 defined in a namespace and imported with a `using' directive, operators
338 defined in the global scope, operators imported implicitly from an
339 anonymous namespace, and the ADL operators mentioned in the previous
341 GDB now also supports proper overload resolution for all the previously
342 mentioned flavors of operators.
344 ** static const class members
346 Printing of static const class members that are initialized in the
347 class definition has been fixed.
349 * Windows Thread Information Block access.
351 On Windows targets, GDB now supports displaying the Windows Thread
352 Information Block (TIB) structure. This structure is visible either
353 by using the new command `info w32 thread-information-block' or, by
354 dereferencing the new convenience variable named `$_tlb', a
355 thread-specific pointer to the TIB. This feature is also supported
356 when remote debugging using GDBserver.
360 Static tracepoints are calls in the user program into a tracing
361 library. One such library is a port of the LTTng kernel tracer to
362 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
363 When debugging with GDBserver, GDB now supports combining the GDB
364 tracepoint machinery with such libraries. For example: the user can
365 use GDB to probe a static tracepoint marker (a call from the user
366 program into the tracing library) with the new "strace" command (see
367 "New commands" below). This creates a "static tracepoint" in the
368 breakpoint list, that can be manipulated with the same feature set
369 as fast and regular tracepoints. E.g., collect registers, local and
370 global variables, collect trace state variables, and define
371 tracepoint conditions. In addition, the user can collect extra
372 static tracepoint marker specific data, by collecting the new
373 $_sdata internal variable. When analyzing the trace buffer, you can
374 inspect $_sdata like any other variable available to GDB. For more
375 information, see the "Tracepoints" chapter in GDB user manual. New
376 remote packets have been defined to support static tracepoints, see
377 the "New remote packets" section below.
379 * Better reconstruction of tracepoints after disconnected tracing
381 GDB will attempt to download the original source form of tracepoint
382 definitions when starting a trace run, and then will upload these
383 upon reconnection to the target, resulting in a more accurate
384 reconstruction of the tracepoints that are in use on the target.
388 You can now exercise direct control over the ways that GDB can
389 affect your program. For instance, you can disallow the setting of
390 breakpoints, so that the program can run continuously (assuming
391 non-stop mode). In addition, the "observer" variable is available
392 to switch all of the different controls; in observer mode, GDB
393 cannot affect the target's behavior at all, which is useful for
394 tasks like diagnosing live systems in the field.
396 * The new convenience variable $_thread holds the number of the
403 Return the address of the Windows Thread Information Block of a given thread.
407 In response to several of the tracepoint packets, the target may now
408 also respond with a number of intermediate `qRelocInsn' request
409 packets before the final result packet, to have GDB handle
410 relocating an instruction to execute at a different address. This
411 is particularly useful for stubs that support fast tracepoints. GDB
412 reports support for this feature in the qSupported packet.
416 List static tracepoint markers in the target program.
420 List static tracepoint markers at a given address in the target
423 qXfer:statictrace:read
425 Read the static trace data collected (by a `collect $_sdata'
426 tracepoint action). The remote stub reports support for this packet
427 to gdb's qSupported query.
431 Send the current settings of GDB's permission flags.
435 Send part of the source (textual) form of a tracepoint definition,
436 which includes location, conditional, and action list.
438 * The source command now accepts a -s option to force searching for the
439 script in the source search path even if the script name specifies
442 * New features in the GDB remote stub, GDBserver
444 - GDBserver now support tracepoints (including fast tracepoints, and
445 static tracepoints). The feature is currently supported by the
446 i386-linux and amd64-linux builds. See the "Tracepoints support
447 in gdbserver" section in the manual for more information.
449 GDBserver JIT compiles the tracepoint's conditional agent
450 expression bytecode into native code whenever possible for low
451 overhead dynamic tracepoints conditionals. For such tracepoints,
452 an expression that examines program state is evaluated when the
453 tracepoint is reached, in order to determine whether to capture
454 trace data. If the condition is simple and false, processing the
455 tracepoint finishes very quickly and no data is gathered.
457 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
458 for static tracepoints support.
460 - GDBserver now supports x86_64 Windows 64-bit debugging.
462 * GDB now sends xmlRegisters= in qSupported packet to indicate that
463 it understands register description.
465 * The --batch flag now disables pagination and queries.
467 * X86 general purpose registers
469 GDB now supports reading/writing byte, word and double-word x86
470 general purpose registers directly. This means you can use, say,
471 $ah or $ax to refer, respectively, to the byte register AH and
472 16-bit word register AX that are actually portions of the 32-bit
473 register EAX or 64-bit register RAX.
475 * The `commands' command now accepts a range of breakpoints to modify.
476 A plain `commands' following a command that creates multiple
477 breakpoints affects all the breakpoints set by that command. This
478 applies to breakpoints set by `rbreak', and also applies when a
479 single `break' command creates multiple breakpoints (e.g.,
480 breakpoints on overloaded c++ functions).
482 * The `rbreak' command now accepts a filename specification as part of
483 its argument, limiting the functions selected by the regex to those
484 in the specified file.
486 * Support for remote debugging Windows and SymbianOS shared libraries
487 from Unix hosts has been improved. Non Windows GDB builds now can
488 understand target reported file names that follow MS-DOS based file
489 system semantics, such as file names that include drive letters and
490 use the backslash character as directory separator. This makes it
491 possible to transparently use the "set sysroot" and "set
492 solib-search-path" on Unix hosts to point as host copies of the
493 target's shared libraries. See the new command "set
494 target-file-system-kind" described below, and the "Commands to
495 specify files" section in the user manual for more information.
499 eval template, expressions...
500 Convert the values of one or more expressions under the control
501 of the string template to a command line, and call it.
503 set target-file-system-kind unix|dos-based|auto
504 show target-file-system-kind
505 Set or show the assumed file system kind for target reported file
508 save breakpoints <filename>
509 Save all current breakpoint definitions to a file suitable for use
510 in a later debugging session. To read the saved breakpoint
511 definitions, use the `source' command.
513 `save tracepoints' is a new alias for `save-tracepoints'. The latter
516 info static-tracepoint-markers
517 Display information about static tracepoint markers in the target.
519 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
520 Define a static tracepoint by probing a marker at the given
521 function, line, address, or marker ID.
525 Enable and disable observer mode.
527 set may-write-registers on|off
528 set may-write-memory on|off
529 set may-insert-breakpoints on|off
530 set may-insert-tracepoints on|off
531 set may-insert-fast-tracepoints on|off
532 set may-interrupt on|off
533 Set individual permissions for GDB effects on the target. Note that
534 some of these settings can have undesirable or surprising
535 consequences, particularly when changed in the middle of a session.
536 For instance, disabling the writing of memory can prevent
537 breakpoints from being inserted, cause single-stepping to fail, or
538 even crash your program, if you disable after breakpoints have been
539 inserted. However, GDB should not crash.
541 set record memory-query on|off
542 show record memory-query
543 Control whether to stop the inferior if memory changes caused
544 by an instruction cannot be recorded.
549 The disassemble command now supports "start,+length" form of two arguments.
553 ** GDB now provides a new directory location, called the python directory,
554 where Python scripts written for GDB can be installed. The location
555 of that directory is <data-directory>/python, where <data-directory>
556 is the GDB data directory. For more details, see section `Scripting
557 GDB using Python' in the manual.
559 ** The GDB Python API now has access to breakpoints, symbols, symbol
560 tables, program spaces, inferiors, threads and frame's code blocks.
561 Additionally, GDB Parameters can now be created from the API, and
562 manipulated via set/show in the CLI.
564 ** New functions gdb.target_charset, gdb.target_wide_charset,
565 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
567 ** New exception gdb.GdbError.
569 ** Pretty-printers are now also looked up in the current program space.
571 ** Pretty-printers can now be individually enabled and disabled.
573 ** GDB now looks for names of Python scripts to auto-load in a
574 special section named `.debug_gdb_scripts', in addition to looking
575 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
577 * Tracepoint actions were unified with breakpoint commands. In particular,
578 there are no longer differences in "info break" output for breakpoints and
579 tracepoints and the "commands" command can be used for both tracepoints and
584 ARM Symbian arm*-*-symbianelf*
586 * D language support.
587 GDB now supports debugging programs written in the D programming
590 * GDB now supports the extended ptrace interface for PowerPC which is
591 available since Linux kernel version 2.6.34. This automatically enables
592 any hardware breakpoints and additional hardware watchpoints available in
593 the processor. The old ptrace interface exposes just one hardware
594 watchpoint and no hardware breakpoints.
596 * GDB is now able to use the Data Value Compare (DVC) register available on
597 embedded PowerPC processors to implement in hardware simple watchpoint
598 conditions of the form:
600 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
602 This works in native GDB running on Linux kernels with the extended ptrace
603 interface mentioned above.
605 *** Changes in GDB 7.1
611 GDB now supports importing of namespaces in C++. This enables the
612 user to inspect variables from imported namespaces. Support for
613 namepace aliasing has also been added. So, if a namespace is
614 aliased in the current scope (e.g. namepace C=A; ) the user can
615 print variables using the alias (e.g. (gdb) print C::x).
619 All known bugs relating to the printing of virtual base class were
620 fixed. It is now possible to call overloaded static methods using a
625 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
626 and reinterpret_cast<> are now handled by the C++ expression parser.
630 Xilinx MicroBlaze microblaze-*-*
635 Xilinx MicroBlaze microblaze
638 * Multi-program debugging.
640 GDB now has support for multi-program (a.k.a. multi-executable or
641 multi-exec) debugging. This allows for debugging multiple inferiors
642 simultaneously each running a different program under the same GDB
643 session. See "Debugging Multiple Inferiors and Programs" in the
644 manual for more information. This implied some user visible changes
645 in the multi-inferior support. For example, "info inferiors" now
646 lists inferiors that are not running yet or that have exited
647 already. See also "New commands" and "New options" below.
649 * New tracing features
651 GDB's tracepoint facility now includes several new features:
653 ** Trace state variables
655 GDB tracepoints now include support for trace state variables, which
656 are variables managed by the target agent during a tracing
657 experiment. They are useful for tracepoints that trigger each
658 other, so for instance one tracepoint can count hits in a variable,
659 and then a second tracepoint has a condition that is true when the
660 count reaches a particular value. Trace state variables share the
661 $-syntax of GDB convenience variables, and can appear in both
662 tracepoint actions and condition expressions. Use the "tvariable"
663 command to create, and "info tvariables" to view; see "Trace State
664 Variables" in the manual for more detail.
668 GDB now includes an option for defining fast tracepoints, which
669 targets may implement more efficiently, such as by installing a jump
670 into the target agent rather than a trap instruction. The resulting
671 speedup can be by two orders of magnitude or more, although the
672 tradeoff is that some program locations on some target architectures
673 might not allow fast tracepoint installation, for instance if the
674 instruction to be replaced is shorter than the jump. To request a
675 fast tracepoint, use the "ftrace" command, with syntax identical to
676 the regular trace command.
678 ** Disconnected tracing
680 It is now possible to detach GDB from the target while it is running
681 a trace experiment, then reconnect later to see how the experiment
682 is going. In addition, a new variable disconnected-tracing lets you
683 tell the target agent whether to continue running a trace if the
684 connection is lost unexpectedly.
688 GDB now has the ability to save the trace buffer into a file, and
689 then use that file as a target, similarly to you can do with
690 corefiles. You can select trace frames, print data that was
691 collected in them, and use tstatus to display the state of the
692 tracing run at the moment that it was saved. To create a trace
693 file, use "tsave <filename>", and to use it, do "target tfile
696 ** Circular trace buffer
698 You can ask the target agent to handle the trace buffer as a
699 circular buffer, discarding the oldest trace frames to make room for
700 newer ones, by setting circular-trace-buffer to on. This feature may
701 not be available for all target agents.
706 The disassemble command, when invoked with two arguments, now requires
707 the arguments to be comma-separated.
710 The info variables command now displays variable definitions. Files
711 which only declare a variable are not shown.
714 The source command is now capable of sourcing Python scripts.
715 This feature is dependent on the debugger being build with Python
718 Related to this enhancement is also the introduction of a new command
719 "set script-extension" (see below).
721 * New commands (for set/show, see "New options" below)
723 record save [<FILENAME>]
724 Save a file (in core file format) containing the process record
725 execution log for replay debugging at a later time.
727 record restore <FILENAME>
728 Restore the process record execution log that was saved at an
729 earlier time, for replay debugging.
731 add-inferior [-copies <N>] [-exec <FILENAME>]
734 clone-inferior [-copies <N>] [ID]
735 Make a new inferior ready to execute the same program another
741 maint info program-spaces
742 List the program spaces loaded into GDB.
744 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
745 show remote interrupt-sequence
746 Allow the user to select one of ^C, a BREAK signal or BREAK-g
747 as the sequence to the remote target in order to interrupt the execution.
748 Ctrl-C is a default. Some system prefers BREAK which is high level of
749 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
750 Magic SysRq g. It is BREAK signal and character 'g'.
752 set remote interrupt-on-connect [on | off]
753 show remote interrupt-on-connect
754 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
755 remote target when gdb connects to it. This is needed when you debug
758 set remotebreak [on | off]
760 Deprecated. Use "set/show remote interrupt-sequence" instead.
762 tvariable $NAME [ = EXP ]
763 Create or modify a trace state variable.
766 List trace state variables and their values.
768 delete tvariable $NAME ...
769 Delete one or more trace state variables.
772 Evaluate the given expressions without collecting anything into the
773 trace buffer. (Valid in tracepoint actions only.)
775 ftrace FN / FILE:LINE / *ADDR
776 Define a fast tracepoint at the given function, line, or address.
778 * New expression syntax
780 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
781 GDB now parses 0b101010 identically with 42.
785 set follow-exec-mode new|same
786 show follow-exec-mode
787 Control whether GDB reuses the same inferior across an exec call or
788 creates a new one. This is useful to be able to restart the old
789 executable after the inferior having done an exec call.
791 set default-collect EXPR, ...
793 Define a list of expressions to be collected at each tracepoint.
794 This is a useful way to ensure essential items are not overlooked,
795 such as registers or a critical global variable.
797 set disconnected-tracing
798 show disconnected-tracing
799 If set to 1, the target is instructed to continue tracing if it
800 loses its connection to GDB. If 0, the target is to stop tracing
803 set circular-trace-buffer
804 show circular-trace-buffer
805 If set to on, the target is instructed to use a circular trace buffer
806 and discard the oldest trace frames instead of stopping the trace due
807 to a full trace buffer. If set to off, the trace stops when the buffer
808 fills up. Some targets may not support this.
810 set script-extension off|soft|strict
811 show script-extension
812 If set to "off", the debugger does not perform any script language
813 recognition, and all sourced files are assumed to be GDB scripts.
814 If set to "soft" (the default), files are sourced according to
815 filename extension, falling back to GDB scripts if the first
817 If set to "strict", files are sourced according to filename extension.
819 set ada trust-PAD-over-XVS on|off
820 show ada trust-PAD-over-XVS
821 If off, activate a workaround against a bug in the debugging information
822 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
823 the GCC sources for more information about the GNAT encoding and
824 PAD types in particular). It is always safe to set this option to
825 off, but this introduces a slight performance penalty. The default
828 * Python API Improvements
830 ** GDB provides the new class gdb.LazyString. This is useful in
831 some pretty-printing cases. The new method gdb.Value.lazy_string
832 provides a simple way to create objects of this type.
834 ** The fields returned by gdb.Type.fields now have an
835 `is_base_class' attribute.
837 ** The new method gdb.Type.range returns the range of an array type.
839 ** The new method gdb.parse_and_eval can be used to parse and
840 evaluate an expression.
845 Define a trace state variable.
848 Get the current value of a trace state variable.
851 Set desired tracing behavior upon disconnection.
854 Set the trace buffer to be linear or circular.
857 Get data about the tracepoints currently in use.
861 Process record now works correctly with hardware watchpoints.
863 Multiple bug fixes have been made to the mips-irix port, making it
864 much more reliable. In particular:
865 - Debugging threaded applications is now possible again. Previously,
866 GDB would hang while starting the program, or while waiting for
867 the program to stop at a breakpoint.
868 - Attaching to a running process no longer hangs.
869 - An error occurring while loading a core file has been fixed.
870 - Changing the value of the PC register now works again. This fixes
871 problems observed when using the "jump" command, or when calling
872 a function from GDB, or even when assigning a new value to $pc.
873 - With the "finish" and "return" commands, the return value for functions
874 returning a small array is now correctly printed.
875 - It is now possible to break on shared library code which gets executed
876 during a shared library init phase (code executed while executing
877 their .init section). Previously, the breakpoint would have no effect.
878 - GDB is now able to backtrace through the signal handler for
879 non-threaded programs.
881 PIE (Position Independent Executable) programs debugging is now supported.
882 This includes debugging execution of PIC (Position Independent Code) shared
883 libraries although for that, it should be possible to run such libraries as an
886 *** Changes in GDB 7.0
888 * GDB now has an interface for JIT compilation. Applications that
889 dynamically generate code can create symbol files in memory and register
890 them with GDB. For users, the feature should work transparently, and
891 for JIT developers, the interface is documented in the GDB manual in the
892 "JIT Compilation Interface" chapter.
894 * Tracepoints may now be conditional. The syntax is as for
895 breakpoints; either an "if" clause appended to the "trace" command,
896 or the "condition" command is available. GDB sends the condition to
897 the target for evaluation using the same bytecode format as is used
898 for tracepoint actions.
900 * The disassemble command now supports: an optional /r modifier, print the
901 raw instructions in hex as well as in symbolic form, and an optional /m
902 modifier to print mixed source+assembly.
904 * Process record and replay
906 In a architecture environment that supports ``process record and
907 replay'', ``process record and replay'' target can record a log of
908 the process execution, and replay it with both forward and reverse
911 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
912 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
913 set execution-direction {forward|reverse}, for targets that support
916 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
917 feature is available with a native GDB running on kernel version
920 * GDB now has support for multi-byte and wide character sets on the
921 target. Strings whose character type is wchar_t, char16_t, or
922 char32_t are now correctly printed. GDB supports wide- and unicode-
923 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
924 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
925 `printf'. This feature requires iconv to work properly; if your
926 system does not have a working iconv, GDB can use GNU libiconv. See
927 the installation instructions for more information.
929 * GDB now supports automatic retrieval of shared library files from
930 remote targets. To use this feature, specify a system root that begins
931 with the `remote:' prefix, either via the `set sysroot' command or via
932 the `--with-sysroot' configure-time option.
934 * "info sharedlibrary" now takes an optional regex of libraries to show,
935 and it now reports if a shared library has no debugging information.
937 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
938 now complete on file names.
940 * When completing in expressions, gdb will attempt to limit
941 completions to allowable structure or union fields, where appropriate.
942 For instance, consider:
944 # struct example { int f1; double f2; };
945 # struct example variable;
948 If the user types TAB at the end of this command line, the available
949 completions will be "f1" and "f2".
951 * Inlined functions are now supported. They show up in backtraces, and
952 the "step", "next", and "finish" commands handle them automatically.
954 * GDB now supports the token-splicing (##) and stringification (#)
955 operators when expanding macros. It also supports variable-arity
958 * GDB now supports inspecting extra signal information, exported by
959 the new $_siginfo convenience variable. The feature is currently
960 implemented on linux ARM, i386 and amd64.
962 * GDB can now display the VFP floating point registers and NEON vector
963 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
964 can provide these registers (requires Linux 2.6.30 or later). Remote
965 and simulator targets may also provide them.
970 Search memory for a sequence of bytes.
973 Turn off `+'/`-' protocol acknowledgments to permit more efficient
974 operation over reliable transport links. Use of this packet is
975 controlled by the `set remote noack-packet' command.
978 Kill the process with the specified process ID. Use this in preference
979 to `k' when multiprocess protocol extensions are supported.
982 Obtains additional operating system information
986 Read or write additional signal information.
988 * Removed remote protocol undocumented extension
990 An undocumented extension to the remote protocol's `S' stop reply
991 packet that permited the stub to pass a process id was removed.
992 Remote servers should use the `T' stop reply packet instead.
994 * GDB now supports multiple function calling conventions according to the
995 DWARF-2 DW_AT_calling_convention function attribute.
997 * The SH target utilizes the aforementioned change to distinguish between gcc
998 and Renesas calling convention. It also adds the new CLI commands
999 `set/show sh calling-convention'.
1001 * GDB can now read compressed debug sections, as produced by GNU gold
1002 with the --compress-debug-sections=zlib flag.
1004 * 64-bit core files are now supported on AIX.
1006 * Thread switching is now supported on Tru64.
1008 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1009 which will be allocated using malloc later in program execution.
1011 * The qXfer:libraries:read remote procotol packet now allows passing a
1012 list of section offsets.
1014 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1015 conditions handling signals delivered during attach or thread creation
1016 have also been fixed.
1018 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1019 From the user's standpoint, all unqualified instances of True and False
1020 are treated as the standard definitions, regardless of context.
1022 * GDB now parses C++ symbol and type names more flexibly. For
1025 template<typename T> class C { };
1028 GDB will now correctly handle all of:
1030 ptype C<char const *>
1031 ptype C<char const*>
1032 ptype C<const char *>
1033 ptype C<const char*>
1035 * New features in the GDB remote stub, gdbserver
1037 - The "--wrapper" command-line argument tells gdbserver to use a
1038 wrapper program to launch programs for debugging.
1040 - On PowerPC and S/390 targets, it is now possible to use a single
1041 gdbserver executable to debug both 32-bit and 64-bit programs.
1042 (This requires gdbserver itself to be built as a 64-bit executable.)
1044 - gdbserver uses the new noack protocol mode for TCP connections to
1045 reduce communications latency, if also supported and enabled in GDB.
1047 - Support for the sparc64-linux-gnu target is now included in
1050 - The amd64-linux build of gdbserver now supports debugging both
1051 32-bit and 64-bit programs.
1053 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1054 now support hardware watchpoints, and will use them automatically
1059 GDB now has support for scripting using Python. Whether this is
1060 available is determined at configure time.
1062 New GDB commands can now be written in Python.
1064 * Ada tasking support
1066 Ada tasks can now be inspected in GDB. The following commands have
1070 Print the list of Ada tasks.
1072 Print detailed information about task number N.
1074 Print the task number of the current task.
1076 Switch the context of debugging to task number N.
1078 * Support for user-defined prefixed commands. The "define" command can
1079 add new commands to existing prefixes, e.g. "target".
1081 * Multi-inferior, multi-process debugging.
1083 GDB now has generalized support for multi-inferior debugging. See
1084 "Debugging Multiple Inferiors" in the manual for more information.
1085 Although availability still depends on target support, the command
1086 set is more uniform now. The GNU/Linux specific multi-forks support
1087 has been migrated to this new framework. This implied some user
1088 visible changes; see "New commands" and also "Removed commands"
1091 * Target descriptions can now describe the target OS ABI. See the
1092 "Target Description Format" section in the user manual for more
1095 * Target descriptions can now describe "compatible" architectures
1096 to indicate that the target can execute applications for a different
1097 architecture in addition to those for the main target architecture.
1098 See the "Target Description Format" section in the user manual for
1101 * Multi-architecture debugging.
1103 GDB now includes general supports for debugging applications on
1104 hybrid systems that use more than one single processor architecture
1105 at the same time. Each such hybrid architecture still requires
1106 specific support to be added. The only hybrid architecture supported
1107 in this version of GDB is the Cell Broadband Engine.
1109 * GDB now supports integrated debugging of Cell/B.E. applications that
1110 use both the PPU and SPU architectures. To enable support for hybrid
1111 Cell/B.E. debugging, you need to configure GDB to support both the
1112 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1113 --enable-targets configure option.
1115 * Non-stop mode debugging.
1117 For some targets, GDB now supports an optional mode of operation in
1118 which you can examine stopped threads while other threads continue
1119 to execute freely. This is referred to as non-stop mode, with the
1120 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1121 section in the user manual for more information.
1123 To be able to support remote non-stop debugging, a remote stub needs
1124 to implement the non-stop mode remote protocol extensions, as
1125 described in the "Remote Non-Stop" section of the user manual. The
1126 GDB remote stub, gdbserver, has been adjusted to support these
1127 extensions on linux targets.
1129 * New commands (for set/show, see "New options" below)
1131 catch syscall [NAME(S) | NUMBER(S)]
1132 Catch system calls. Arguments, which should be names of system
1133 calls or their numbers, mean catch only those syscalls. Without
1134 arguments, every syscall will be caught. When the inferior issues
1135 any of the specified syscalls, GDB will stop and announce the system
1136 call, both when it is called and when its call returns. This
1137 feature is currently available with a native GDB running on the
1138 Linux Kernel, under the following architectures: x86, x86_64,
1139 PowerPC and PowerPC64.
1141 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1143 Search memory for a sequence of bytes.
1145 maint set python print-stack
1146 maint show python print-stack
1147 Show a stack trace when an error is encountered in a Python script.
1150 Invoke CODE by passing it to the Python interpreter.
1155 These allow macros to be defined, undefined, and listed
1159 Show operating system information about processes.
1162 List the inferiors currently under GDB's control.
1165 Switch focus to inferior number NUM.
1168 Detach from inferior number NUM.
1171 Kill inferior number NUM.
1175 set spu stop-on-load
1176 show spu stop-on-load
1177 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1179 set spu auto-flush-cache
1180 show spu auto-flush-cache
1181 Control whether to automatically flush the software-managed cache
1182 during Cell/B.E. debugging.
1184 set sh calling-convention
1185 show sh calling-convention
1186 Control the calling convention used when calling SH target functions.
1189 show debug timestamp
1190 Control display of timestamps with GDB debugging output.
1192 set disassemble-next-line
1193 show disassemble-next-line
1194 Control display of disassembled source lines or instructions when
1197 set remote noack-packet
1198 show remote noack-packet
1199 Set/show the use of remote protocol QStartNoAckMode packet. See above
1200 under "New remote packets."
1202 set remote query-attached-packet
1203 show remote query-attached-packet
1204 Control use of remote protocol `qAttached' (query-attached) packet.
1206 set remote read-siginfo-object
1207 show remote read-siginfo-object
1208 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1211 set remote write-siginfo-object
1212 show remote write-siginfo-object
1213 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1216 set remote reverse-continue
1217 show remote reverse-continue
1218 Control use of remote protocol 'bc' (reverse-continue) packet.
1220 set remote reverse-step
1221 show remote reverse-step
1222 Control use of remote protocol 'bs' (reverse-step) packet.
1224 set displaced-stepping
1225 show displaced-stepping
1226 Control displaced stepping mode. Displaced stepping is a way to
1227 single-step over breakpoints without removing them from the debuggee.
1228 Also known as "out-of-line single-stepping".
1231 show debug displaced
1232 Control display of debugging info for displaced stepping.
1234 maint set internal-error
1235 maint show internal-error
1236 Control what GDB does when an internal error is detected.
1238 maint set internal-warning
1239 maint show internal-warning
1240 Control what GDB does when an internal warning is detected.
1245 Use a wrapper program to launch programs for debugging.
1247 set multiple-symbols (all|ask|cancel)
1248 show multiple-symbols
1249 The value of this variable can be changed to adjust the debugger behavior
1250 when an expression or a breakpoint location contains an ambiguous symbol
1251 name (an overloaded function name, for instance).
1253 set breakpoint always-inserted
1254 show breakpoint always-inserted
1255 Keep breakpoints always inserted in the target, as opposed to inserting
1256 them when resuming the target, and removing them when the target stops.
1257 This option can improve debugger performance on slow remote targets.
1259 set arm fallback-mode (arm|thumb|auto)
1260 show arm fallback-mode
1261 set arm force-mode (arm|thumb|auto)
1263 These commands control how ARM GDB determines whether instructions
1264 are ARM or Thumb. The default for both settings is auto, which uses
1265 the current CPSR value for instructions without symbols; previous
1266 versions of GDB behaved as if "set arm fallback-mode arm".
1268 set disable-randomization
1269 show disable-randomization
1270 Standalone programs run with the virtual address space randomization enabled
1271 by default on some platforms. This option keeps the addresses stable across
1272 multiple debugging sessions.
1276 Control whether other threads are stopped or not when some thread hits
1281 Requests that asynchronous execution is enabled in the target, if available.
1282 In this case, it's possible to resume target in the background, and interact
1283 with GDB while the target is running. "show target-async" displays the
1284 current state of asynchronous execution of the target.
1286 set target-wide-charset
1287 show target-wide-charset
1288 The target-wide-charset is the name of the character set that GDB
1289 uses when printing characters whose type is wchar_t.
1291 set tcp auto-retry (on|off)
1293 set tcp connect-timeout
1294 show tcp connect-timeout
1295 These commands allow GDB to retry failed TCP connections to a remote stub
1296 with a specified timeout period; this is useful if the stub is launched
1297 in parallel with GDB but may not be ready to accept connections immediately.
1299 set libthread-db-search-path
1300 show libthread-db-search-path
1301 Control list of directories which GDB will search for appropriate
1304 set schedule-multiple (on|off)
1305 show schedule-multiple
1306 Allow GDB to resume all threads of all processes or only threads of
1307 the current process.
1311 Use more aggressive caching for accesses to the stack. This improves
1312 performance of remote debugging (particularly backtraces) without
1313 affecting correctness.
1315 set interactive-mode (on|off|auto)
1316 show interactive-mode
1317 Control whether GDB runs in interactive mode (on) or not (off).
1318 When in interactive mode, GDB waits for the user to answer all
1319 queries. Otherwise, GDB does not wait and assumes the default
1320 answer. When set to auto (the default), GDB determines which
1321 mode to use based on the stdin settings.
1326 For program forks, this is replaced by the new more generic `info
1327 inferiors' command. To list checkpoints, you can still use the
1328 `info checkpoints' command, which was an alias for the `info forks'
1332 Replaced by the new `inferior' command. To switch between
1333 checkpoints, you can still use the `restart' command, which was an
1334 alias for the `fork' command.
1337 This is removed, since some targets don't have a notion of
1338 processes. To switch between processes, you can still use the
1339 `inferior' command using GDB's own inferior number.
1342 For program forks, this is replaced by the new more generic `kill
1343 inferior' command. To delete a checkpoint, you can still use the
1344 `delete checkpoint' command, which was an alias for the `delete
1348 For program forks, this is replaced by the new more generic `detach
1349 inferior' command. To detach a checkpoint, you can still use the
1350 `detach checkpoint' command, which was an alias for the `detach
1353 * New native configurations
1355 x86/x86_64 Darwin i[34567]86-*-darwin*
1357 x86_64 MinGW x86_64-*-mingw*
1361 Lattice Mico32 lm32-*
1362 x86 DICOS i[34567]86-*-dicos*
1363 x86_64 DICOS x86_64-*-dicos*
1366 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1367 (mingw32ce) debugging.
1373 These commands were actually not implemented on any target.
1375 *** Changes in GDB 6.8
1377 * New native configurations
1379 NetBSD/hppa hppa*-*netbsd*
1380 Xtensa GNU/Linux xtensa*-*-linux*
1384 NetBSD/hppa hppa*-*-netbsd*
1385 Xtensa GNU/Lunux xtensa*-*-linux*
1387 * Change in command line behavior -- corefiles vs. process ids.
1389 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1390 attaching to process NUMBER fails, GDB no longer attempts to open a
1391 core file named NUMBER. Attaching to a program using the -c option
1392 is no longer supported. Instead, use the '-p' or '--pid' options.
1394 * GDB can now be built as a native debugger for debugging Windows x86
1395 (mingw32) Portable Executable (PE) programs.
1397 * Pending breakpoints no longer change their number when their address
1400 * GDB now supports breakpoints with multiple locations,
1401 including breakpoints on C++ constructors, inside C++ templates,
1402 and in inlined functions.
1404 * GDB's ability to debug optimized code has been improved. GDB more
1405 accurately identifies function bodies and lexical blocks that occupy
1406 more than one contiguous range of addresses.
1408 * Target descriptions can now describe registers for PowerPC.
1410 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1411 registers on PowerPC targets.
1413 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1414 targets even when the libthread_db library is not available.
1416 * The GDB remote stub, gdbserver, now supports the new file transfer
1417 commands (remote put, remote get, and remote delete).
1419 * The GDB remote stub, gdbserver, now supports run and attach in
1420 extended-remote mode.
1422 * hppa*64*-*-hpux11* target broken
1423 The debugger is unable to start a program and fails with the following
1424 error: "Error trying to get information about dynamic linker".
1425 The gdb-6.7 release is also affected.
1427 * GDB now supports the --enable-targets= configure option to allow
1428 building a single GDB executable that supports multiple remote
1429 target architectures.
1431 * GDB now supports debugging C and C++ programs which use the
1432 Decimal Floating Point extension. In addition, the PowerPC target
1433 now has a set of pseudo-registers to inspect decimal float values
1434 stored in two consecutive float registers.
1436 * The -break-insert MI command can optionally create pending
1439 * Improved support for debugging Ada
1440 Many improvements to the Ada language support have been made. These
1442 - Better support for Ada2005 interface types
1443 - Improved handling of arrays and slices in general
1444 - Better support for Taft-amendment types
1445 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1447 - Improved command completion in Ada
1450 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1455 set print frame-arguments (all|scalars|none)
1456 show print frame-arguments
1457 The value of this variable can be changed to control which argument
1458 values should be printed by the debugger when displaying a frame.
1463 Transfer files to and from a remote target, and delete remote files.
1470 Transfer files to and from a remote target, and delete remote files.
1472 * New remote packets
1479 Open, close, read, write, and delete files on the remote system.
1482 Attach to an existing process on the remote system, in extended-remote
1486 Run a new process on the remote system, in extended-remote mode.
1488 *** Changes in GDB 6.7
1490 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1491 bfd, libiberty and opcodes, as revealed by static analysis donated by
1492 Coverity, Inc. (http://scan.coverity.com).
1494 * When looking up multiply-defined global symbols, GDB will now prefer the
1495 symbol definition in the current shared library if it was built using the
1496 -Bsymbolic linker option.
1498 * When the Text User Interface (TUI) is not configured, GDB will now
1499 recognize the -tui command-line option and print a message that the TUI
1502 * The GDB remote stub, gdbserver, now has lower overhead for high
1503 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1505 * GDB for MIPS targets now autodetects whether a remote target provides
1506 32-bit or 64-bit register values.
1508 * Support for C++ member pointers has been improved.
1510 * GDB now understands XML target descriptions, which specify the
1511 target's overall architecture. GDB can read a description from
1512 a local file or over the remote serial protocol.
1514 * Vectors of single-byte data use a new integer type which is not
1515 automatically displayed as character or string data.
1517 * The /s format now works with the print command. It displays
1518 arrays of single-byte integers and pointers to single-byte integers
1521 * Target descriptions can now describe target-specific registers,
1522 for architectures which have implemented the support (currently
1523 only ARM, M68K, and MIPS).
1525 * GDB and the GDB remote stub, gdbserver, now support the XScale
1528 * The GDB remote stub, gdbserver, has been updated to support
1529 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1530 has been rewritten to use the standard GDB remote protocol.
1532 * GDB can now step into C++ functions which are called through thunks.
1534 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1536 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1537 layout. It also supports a TextSeg= and DataSeg= response when only
1538 segment base addresses (rather than offsets) are available.
1540 * The /i format now outputs any trailing branch delay slot instructions
1541 immediately following the last instruction within the count specified.
1543 * The GDB remote protocol "T" stop reply packet now supports a
1544 "library" response. Combined with the new "qXfer:libraries:read"
1545 packet, this response allows GDB to debug shared libraries on targets
1546 where the operating system manages the list of loaded libraries (e.g.
1547 Windows and SymbianOS).
1549 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1550 (DLLs) on Windows and Windows CE targets.
1552 * GDB now supports a faster verification that a .debug file matches its binary
1553 according to its build-id signature, if the signature is present.
1559 Enable or disable hardware flow control (RTS/CTS) on the serial port
1560 when debugging using remote targets.
1562 set mem inaccessible-by-default
1563 show mem inaccessible-by-default
1564 If the target supplies a memory map, for instance via the remote
1565 protocol's "qXfer:memory-map:read" packet, setting this variable
1566 prevents GDB from accessing memory outside the memory map. This
1567 is useful for targets with memory mapped registers or which react
1568 badly to accesses of unmapped address space.
1570 set breakpoint auto-hw
1571 show breakpoint auto-hw
1572 If the target supplies a memory map, for instance via the remote
1573 protocol's "qXfer:memory-map:read" packet, setting this variable
1574 lets GDB use hardware breakpoints automatically for memory regions
1575 where it can not use software breakpoints. This covers both the
1576 "break" command and internal breakpoints used for other commands
1577 including "next" and "finish".
1580 catch exception unhandled
1581 Stop the program execution when Ada exceptions are raised.
1584 Stop the program execution when an Ada assertion failed.
1588 Set an alternate system root for target files. This is a more
1589 general version of "set solib-absolute-prefix", which is now
1590 an alias to "set sysroot".
1593 Provide extended SPU facility status information. This set of
1594 commands is available only when debugging the Cell/B.E. SPU
1597 * New native configurations
1599 OpenBSD/sh sh*-*openbsd*
1602 unset tdesc filename
1604 Use the specified local file as an XML target description, and do
1605 not query the target for its built-in description.
1609 OpenBSD/sh sh*-*-openbsd*
1610 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1611 Toshiba Media Processor mep-elf
1613 * New remote packets
1616 Ignore the specified signals; pass them directly to the debugged program
1617 without stopping other threads or reporting them to GDB.
1619 qXfer:features:read:
1620 Read an XML target description from the target, which describes its
1625 Read or write contents of an spufs file on the target system. These
1626 packets are available only on the Cell/B.E. SPU architecture.
1628 qXfer:libraries:read:
1629 Report the loaded shared libraries. Combined with new "T" packet
1630 response, this packet allows GDB to debug shared libraries on
1631 targets where the operating system manages the list of loaded
1632 libraries (e.g. Windows and SymbianOS).
1636 Support for these obsolete configurations has been removed.
1644 i[34567]86-*-lynxos*
1645 i[34567]86-*-netware*
1646 i[34567]86-*-sco3.2v5*
1647 i[34567]86-*-sco3.2v4*
1649 i[34567]86-*-sysv4.2*
1652 i[34567]86-*-unixware2*
1653 i[34567]86-*-unixware*
1662 * Other removed features
1669 Various m68k-only ROM monitors.
1676 Various Renesas ROM monitors and debugging interfaces for SH and
1681 Support for a Macraigor serial interface to on-chip debugging.
1682 GDB does not directly support the newer parallel or USB
1687 A debug information format. The predecessor to DWARF 2 and
1688 DWARF 3, which are still supported.
1690 Support for the HP aCC compiler on HP-UX/PA-RISC
1692 SOM-encapsulated symbolic debugging information, automatic
1693 invocation of pxdb, and the aCC custom C++ ABI. This does not
1694 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1695 with aCC can still be debugged on an assembly level.
1697 MIPS ".pdr" sections
1699 A MIPS-specific format used to describe stack frame layout
1700 in debugging information.
1704 GDB could work with an older version of Guile to debug
1705 the interpreter and Scheme programs running in it.
1707 set mips stack-arg-size
1708 set mips saved-gpreg-size
1710 Use "set mips abi" to control parameter passing for MIPS.
1712 *** Changes in GDB 6.6
1717 Cell Broadband Engine SPU spu-elf
1719 * GDB can now be configured as a cross-debugger targeting native Windows
1720 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1721 running on a Windows system over TCP/IP to debug Windows programs.
1723 * The GDB remote stub, gdbserver, has been updated to support Windows and
1724 Cygwin debugging. Both single-threaded and multi-threaded programs are
1727 * The "set trust-readonly-sections" command works again. This command was
1728 broken in GDB 6.3, 6.4, and 6.5.
1730 * The "load" command now supports writing to flash memory, if the remote
1731 stub provides the required support.
1733 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1734 longer requires symbolic debug information (e.g. DWARF-2).
1739 unset substitute-path
1740 show substitute-path
1741 Manage a list of substitution rules that GDB uses to rewrite the name
1742 of the directories where the sources are located. This can be useful
1743 for instance when the sources were moved to a different location
1744 between compilation and debugging.
1748 Print each CLI command as it is executed. Each command is prefixed with
1749 a number of `+' symbols representing the nesting depth.
1750 The source command now has a `-v' option to enable the same feature.
1754 The ARM Demon monitor support (RDP protocol, "target rdp").
1756 Kernel Object Display, an embedded debugging feature which only worked with
1757 an obsolete version of Cisco IOS.
1759 The 'set download-write-size' and 'show download-write-size' commands.
1761 * New remote packets
1764 Tell a stub about GDB client features, and request remote target features.
1765 The first feature implemented is PacketSize, which allows the target to
1766 specify the size of packets it can handle - to minimize the number of
1767 packets required and improve performance when connected to a remote
1771 Fetch an OS auxilliary vector from the remote stub. This packet is a
1772 more efficient replacement for qPart:auxv:read.
1774 qXfer:memory-map:read:
1775 Fetch a memory map from the remote stub, including information about
1776 RAM, ROM, and flash memory devices.
1781 Erase and program a flash memory device.
1783 * Removed remote packets
1786 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1787 used it, and only gdbserver implemented it.
1789 *** Changes in GDB 6.5
1793 Renesas M32C/M16C m32c-elf
1795 Morpho Technologies ms1 ms1-elf
1799 init-if-undefined Initialize a convenience variable, but
1800 only if it doesn't already have a value.
1802 The following commands are presently only implemented for native GNU/Linux:
1804 checkpoint Save a snapshot of the program state.
1806 restart <n> Return the program state to a
1807 previously saved state.
1809 info checkpoints List currently saved checkpoints.
1811 delete-checkpoint <n> Delete a previously saved checkpoint.
1813 set|show detach-on-fork Tell gdb whether to detach from a newly
1814 forked process, or to keep debugging it.
1816 info forks List forks of the user program that
1817 are available to be debugged.
1819 fork <n> Switch to debugging one of several
1820 forks of the user program that are
1821 available to be debugged.
1823 delete-fork <n> Delete a fork from the list of forks
1824 that are available to be debugged (and
1825 kill the forked process).
1827 detach-fork <n> Delete a fork from the list of forks
1828 that are available to be debugged (and
1829 allow the process to continue).
1833 Morpho Technologies ms2 ms1-elf
1835 * Improved Windows host support
1837 GDB now builds as a cross debugger hosted on i686-mingw32, including
1838 native console support, and remote communications using either
1839 network sockets or serial ports.
1841 * Improved Modula-2 language support
1843 GDB can now print most types in the Modula-2 syntax. This includes:
1844 basic types, set types, record types, enumerated types, range types,
1845 pointer types and ARRAY types. Procedure var parameters are correctly
1846 printed and hexadecimal addresses and character constants are also
1847 written in the Modula-2 syntax. Best results can be obtained by using
1848 GNU Modula-2 together with the -gdwarf-2 command line option.
1852 The ARM rdi-share module.
1854 The Netware NLM debug server.
1856 *** Changes in GDB 6.4
1858 * New native configurations
1860 OpenBSD/arm arm*-*-openbsd*
1861 OpenBSD/mips64 mips64-*-openbsd*
1865 Morpho Technologies ms1 ms1-elf
1867 * New command line options
1869 --batch-silent As for --batch, but totally silent.
1870 --return-child-result The debugger will exist with the same value
1871 the child (debugged) program exited with.
1872 --eval-command COMMAND, -ex COMMAND
1873 Execute a single GDB CLI command. This may be
1874 specified multiple times and in conjunction
1875 with the --command (-x) option.
1877 * Deprecated commands removed
1879 The following commands, that were deprecated in 2000, have been
1883 set|show arm disassembly-flavor set|show arm disassembler
1884 othernames set arm disassembler
1885 set|show remotedebug set|show debug remote
1886 set|show archdebug set|show debug arch
1887 set|show eventdebug set|show debug event
1890 * New BSD user-level threads support
1892 It is now possible to debug programs using the user-level threads
1893 library on OpenBSD and FreeBSD. Currently supported (target)
1896 FreeBSD/amd64 x86_64-*-freebsd*
1897 FreeBSD/i386 i386-*-freebsd*
1898 OpenBSD/i386 i386-*-openbsd*
1900 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1901 are not yet supported.
1903 * New support for Matsushita MN10300 w/sim added
1904 (Work in progress). mn10300-elf.
1906 * REMOVED configurations and files
1908 VxWorks and the XDR protocol *-*-vxworks
1909 Motorola MCORE mcore-*-*
1910 National Semiconductor NS32000 ns32k-*-*
1912 * New "set print array-indexes" command
1914 After turning this setting "on", GDB prints the index of each element
1915 when displaying arrays. The default is "off" to preserve the previous
1918 * VAX floating point support
1920 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1922 * User-defined command support
1924 In addition to using $arg0..$arg9 for argument passing, it is now possible
1925 to use $argc to determine now many arguments have been passed. See the
1926 section on user-defined commands in the user manual for more information.
1928 *** Changes in GDB 6.3:
1930 * New command line option
1932 GDB now accepts -l followed by a number to set the timeout for remote
1935 * GDB works with GCC -feliminate-dwarf2-dups
1937 GDB now supports a more compact representation of DWARF-2 debug
1938 information using DW_FORM_ref_addr references. These are produced
1939 by GCC with the option -feliminate-dwarf2-dups and also by some
1940 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1941 to use -feliminate-dwarf2-dups.
1943 * Internationalization
1945 When supported by the host system, GDB will be built with
1946 internationalization (libintl). The task of marking up the sources is
1947 continued, we're looking forward to our first translation.
1951 Initial support for debugging programs compiled with the GNAT
1952 implementation of the Ada programming language has been integrated
1953 into GDB. In this release, support is limited to expression evaluation.
1955 * New native configurations
1957 GNU/Linux/m32r m32r-*-linux-gnu
1961 GDB's remote protocol now includes support for the 'p' packet. This
1962 packet is used to fetch individual registers from a remote inferior.
1964 * END-OF-LIFE registers[] compatibility module
1966 GDB's internal register infrastructure has been completely rewritten.
1967 The new infrastructure making possible the implementation of key new
1968 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1971 GDB 6.3 will be the last release to include the the registers[]
1972 compatibility module that allowed out-of-date configurations to
1973 continue to work. This change directly impacts the following
1983 powerpc bdm protocol
1985 Unless there is activity to revive these configurations, they will be
1986 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1988 * OBSOLETE configurations and files
1990 Configurations that have been declared obsolete in this release have
1991 been commented out. Unless there is activity to revive these
1992 configurations, the next release of GDB will have their sources
1993 permanently REMOVED.
2002 *** Changes in GDB 6.2.1:
2004 * MIPS `break main; run' gave an heuristic-fence-post warning
2006 When attempting to run even a simple program, a warning about
2007 heuristic-fence-post being hit would be reported. This problem has
2010 * MIPS IRIX 'long double' crashed GDB
2012 When examining a long double variable, GDB would get a segmentation
2013 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2014 IRIX long double values).
2018 A bug in the VAX stack code was causing problems with the "next"
2019 command. This problem has been fixed.
2021 *** Changes in GDB 6.2:
2023 * Fix for ``many threads''
2025 On GNU/Linux systems that use the NPTL threads library, a program
2026 rapidly creating and deleting threads would confuse GDB leading to the
2029 ptrace: No such process.
2030 thread_db_get_info: cannot get thread info: generic error
2032 This problem has been fixed.
2034 * "-async" and "-noasync" options removed.
2036 Support for the broken "-noasync" option has been removed (it caused
2039 * New ``start'' command.
2041 This command runs the program until the begining of the main procedure.
2043 * New BSD Kernel Data Access Library (libkvm) interface
2045 Using ``target kvm'' it is now possible to debug kernel core dumps and
2046 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2047 platforms. Currently supported (native-only) configurations are:
2049 FreeBSD/amd64 x86_64-*-freebsd*
2050 FreeBSD/i386 i?86-*-freebsd*
2051 NetBSD/i386 i?86-*-netbsd*
2052 NetBSD/m68k m68*-*-netbsd*
2053 NetBSD/sparc sparc-*-netbsd*
2054 OpenBSD/amd64 x86_64-*-openbsd*
2055 OpenBSD/i386 i?86-*-openbsd*
2056 OpenBSD/m68k m68*-openbsd*
2057 OpenBSD/sparc sparc-*-openbsd*
2059 * Signal trampoline code overhauled
2061 Many generic problems with GDB's signal handling code have been fixed.
2062 These include: backtraces through non-contiguous stacks; recognition
2063 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2064 call; backtrace through a signal trampoline; step into and out of
2065 signal handlers; and single-stepping in the signal trampoline.
2067 Please note that kernel bugs are a limiting factor here. These
2068 features have been shown to work on an s390 GNU/Linux system that
2069 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2071 * Cygwin support for DWARF 2 added.
2073 * New native configurations
2075 GNU/Linux/hppa hppa*-*-linux*
2076 OpenBSD/hppa hppa*-*-openbsd*
2077 OpenBSD/m68k m68*-*-openbsd*
2078 OpenBSD/m88k m88*-*-openbsd*
2079 OpenBSD/powerpc powerpc-*-openbsd*
2080 NetBSD/vax vax-*-netbsd*
2081 OpenBSD/vax vax-*-openbsd*
2083 * END-OF-LIFE frame compatibility module
2085 GDB's internal frame infrastructure has been completely rewritten.
2086 The new infrastructure making it possible to support key new features
2087 including DWARF 2 Call Frame Information. To aid in the task of
2088 migrating old configurations to this new infrastructure, a
2089 compatibility module, that allowed old configurations to continue to
2090 work, was also included.
2092 GDB 6.2 will be the last release to include this frame compatibility
2093 module. This change directly impacts the following configurations:
2103 Unless there is activity to revive these configurations, they will be
2104 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2106 * REMOVED configurations and files
2108 Sun 3, running SunOS 3 m68*-*-sunos3*
2109 Sun 3, running SunOS 4 m68*-*-sunos4*
2110 Sun 2, running SunOS 3 m68000-*-sunos3*
2111 Sun 2, running SunOS 4 m68000-*-sunos4*
2112 Motorola 680x0 running LynxOS m68*-*-lynxos*
2113 AT&T 3b1/Unix pc m68*-att-*
2114 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2115 decstation mips-dec-* mips-little-*
2116 riscos mips-*-riscos* mips-*-sysv*
2117 sonymips mips-sony-*
2118 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2120 *** Changes in GDB 6.1.1:
2122 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2124 The TUI (Text-mode User Interface) is now built as part of a default
2125 GDB configuration. It is enabled by either selecting the TUI with the
2126 command line option "-i=tui" or by running the separate "gdbtui"
2127 program. For more information on the TUI, see the manual "Debugging
2130 * Pending breakpoint support (also included in GDB 6.1)
2132 Support has been added to allow you to specify breakpoints in shared
2133 libraries that have not yet been loaded. If a breakpoint location
2134 cannot be found, and the "breakpoint pending" option is set to auto,
2135 GDB queries you if you wish to make the breakpoint pending on a future
2136 shared-library load. If and when GDB resolves the breakpoint symbol,
2137 the pending breakpoint is removed as one or more regular breakpoints
2140 Pending breakpoints are very useful for GCJ Java debugging.
2142 * Fixed ISO-C build problems
2144 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2145 non ISO-C code that stopped them being built using a more strict ISO-C
2146 compiler (e.g., IBM's C compiler).
2148 * Fixed build problem on IRIX 5
2150 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2151 wasn't able to compile compile on an IRIX 5 system.
2153 * Added execute permission to gdb/gdbserver/configure
2155 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2156 permission. This bug would cause configure to fail on a number of
2157 systems (Solaris, IRIX). Ref: server/519.
2159 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2161 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2162 has been updated to use constant array sizes.
2164 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2166 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2167 its generated DWARF Call Frame Info. This encoding was causing GDB to
2168 panic, that panic has been fixed. Ref: gdb/1628.
2170 * Fixed a problem when examining parameters in shared library code.
2172 When examining parameters in optimized shared library code generated
2173 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2174 not available''. GDB now correctly displays the variable's value.
2176 *** Changes in GDB 6.1:
2178 * Removed --with-mmalloc
2180 Support for the mmalloc memory manager has been removed, as it
2181 conflicted with the internal gdb byte cache.
2183 * Changes in AMD64 configurations
2185 The AMD64 target now includes the %cs and %ss registers. As a result
2186 the AMD64 remote protocol has changed; this affects the floating-point
2187 and SSE registers. If you rely on those registers for your debugging,
2188 you should upgrade gdbserver on the remote side.
2190 * Revised SPARC target
2192 The SPARC target has been completely revised, incorporating the
2193 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2194 support for LynxOS and SunOS 4 has been dropped. Calling functions
2195 from within GDB on operating systems with a non-executable stack
2196 (Solaris, OpenBSD) now works.
2200 GDB has a new C++ demangler which does a better job on the mangled
2201 names generated by current versions of g++. It also runs faster, so
2202 with this and other changes gdb should now start faster on large C++
2205 * DWARF 2 Location Expressions
2207 GDB support for location expressions has been extended to support function
2208 arguments and frame bases. Older versions of GDB could crash when they
2211 * C++ nested types and namespaces
2213 GDB's support for nested types and namespaces in C++ has been
2214 improved, especially if you use the DWARF 2 debugging format. (This
2215 is the default for recent versions of GCC on most platforms.)
2216 Specifically, if you have a class "Inner" defined within a class or
2217 namespace "Outer", then GDB realizes that the class's name is
2218 "Outer::Inner", not simply "Inner". This should greatly reduce the
2219 frequency of complaints about not finding RTTI symbols. In addition,
2220 if you are stopped at inside of a function defined within a namespace,
2221 GDB modifies its name lookup accordingly.
2223 * New native configurations
2225 NetBSD/amd64 x86_64-*-netbsd*
2226 OpenBSD/amd64 x86_64-*-openbsd*
2227 OpenBSD/alpha alpha*-*-openbsd*
2228 OpenBSD/sparc sparc-*-openbsd*
2229 OpenBSD/sparc64 sparc64-*-openbsd*
2231 * New debugging protocols
2233 M32R with SDI protocol m32r-*-elf*
2235 * "set prompt-escape-char" command deleted.
2237 The command "set prompt-escape-char" has been deleted. This command,
2238 and its very obscure effet on GDB's prompt, was never documented,
2239 tested, nor mentioned in the NEWS file.
2241 * OBSOLETE configurations and files
2243 Configurations that have been declared obsolete in this release have
2244 been commented out. Unless there is activity to revive these
2245 configurations, the next release of GDB will have their sources
2246 permanently REMOVED.
2248 Sun 3, running SunOS 3 m68*-*-sunos3*
2249 Sun 3, running SunOS 4 m68*-*-sunos4*
2250 Sun 2, running SunOS 3 m68000-*-sunos3*
2251 Sun 2, running SunOS 4 m68000-*-sunos4*
2252 Motorola 680x0 running LynxOS m68*-*-lynxos*
2253 AT&T 3b1/Unix pc m68*-att-*
2254 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2255 decstation mips-dec-* mips-little-*
2256 riscos mips-*-riscos* mips-*-sysv*
2257 sonymips mips-sony-*
2258 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2260 * REMOVED configurations and files
2262 SGI Irix-4.x mips-sgi-irix4 or iris4
2263 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2264 Z8000 simulator z8k-zilog-none or z8ksim
2265 Matsushita MN10200 w/simulator mn10200-*-*
2266 H8/500 simulator h8500-hitachi-hms or h8500hms
2267 HP/PA running BSD hppa*-*-bsd*
2268 HP/PA running OSF/1 hppa*-*-osf*
2269 HP/PA Pro target hppa*-*-pro*
2270 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2271 386BSD i[3456]86-*-bsd*
2272 Sequent family i[3456]86-sequent-sysv4*
2273 i[3456]86-sequent-sysv*
2274 i[3456]86-sequent-bsd*
2275 SPARC running LynxOS sparc-*-lynxos*
2276 SPARC running SunOS 4 sparc-*-sunos4*
2277 Tsqware Sparclet sparclet-*-*
2278 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2280 *** Changes in GDB 6.0:
2284 Support for debugging the Objective-C programming language has been
2285 integrated into GDB.
2287 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2289 DWARF 2's Call Frame Information makes available compiler generated
2290 information that more exactly describes the program's run-time stack.
2291 By using this information, GDB is able to provide more robust stack
2294 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2295 have been updated to use a new backtrace mechanism which includes
2296 DWARF 2 CFI support.
2300 GDB's remote protocol has been extended to include support for hosted
2301 file I/O (where the remote target uses GDB's file system). See GDB's
2302 remote protocol documentation for details.
2304 * All targets using the new architecture framework.
2306 All of GDB's targets have been updated to use the new internal
2307 architecture framework. The way is now open for future GDB releases
2308 to include cross-architecture native debugging support (i386 on amd64,
2311 * GNU/Linux's Thread Local Storage (TLS)
2313 GDB now includes support for for the GNU/Linux implementation of
2314 per-thread variables.
2316 * GNU/Linux's Native POSIX Thread Library (NPTL)
2318 GDB's thread code has been updated to work with either the new
2319 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2321 * Separate debug info.
2323 GDB, in conjunction with BINUTILS, now supports a mechanism for
2324 automatically loading debug information from a separate file. Instead
2325 of shipping full debug and non-debug versions of system libraries,
2326 system integrators can now instead ship just the stripped libraries
2327 and optional debug files.
2329 * DWARF 2 Location Expressions
2331 DWARF 2 Location Expressions allow the compiler to more completely
2332 describe the location of variables (even in optimized code) to the
2335 GDB now includes preliminary support for location expressions (support
2336 for DW_OP_piece is still missing).
2340 A number of long standing bugs that caused GDB to die while starting a
2341 Java application have been fixed. GDB's Java support is now
2342 considered "useable".
2344 * GNU/Linux support for fork, vfork, and exec.
2346 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2347 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2350 * GDB supports logging output to a file
2352 There are two new commands, "set logging" and "show logging", which can be
2353 used to capture GDB's output to a file.
2355 * The meaning of "detach" has changed for gdbserver
2357 The "detach" command will now resume the application, as documented. To
2358 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2361 * d10v, m68hc11 `regs' command deprecated
2363 The `info registers' command has been updated so that it displays the
2364 registers using a format identical to the old `regs' command.
2368 A new command, "maint set profile on/off", has been added. This command can
2369 be used to enable or disable profiling while running GDB, to profile a
2370 session or a set of commands. In addition there is a new configure switch,
2371 "--enable-profiling", which will cause GDB to be compiled with profiling
2372 data, for more informative profiling results.
2374 * Default MI syntax changed to "mi2".
2376 The default MI (machine interface) syntax, enabled by the command line
2377 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2378 "mi1", can be enabled by specifying the option "-i=mi1".
2380 Support for the original "mi0" syntax (included in GDB 5.0) has been
2383 Fix for gdb/192: removed extraneous space when displaying frame level.
2384 Fix for gdb/672: update changelist is now output in mi list format.
2385 Fix for gdb/702: a -var-assign that updates the value now shows up
2386 in a subsequent -var-update.
2388 * New native configurations.
2390 FreeBSD/amd64 x86_64-*-freebsd*
2392 * Multi-arched targets.
2394 HP/PA HPUX11 hppa*-*-hpux*
2395 Renesas M32R/D w/simulator m32r-*-elf*
2397 * OBSOLETE configurations and files
2399 Configurations that have been declared obsolete in this release have
2400 been commented out. Unless there is activity to revive these
2401 configurations, the next release of GDB will have their sources
2402 permanently REMOVED.
2404 Z8000 simulator z8k-zilog-none or z8ksim
2405 Matsushita MN10200 w/simulator mn10200-*-*
2406 H8/500 simulator h8500-hitachi-hms or h8500hms
2407 HP/PA running BSD hppa*-*-bsd*
2408 HP/PA running OSF/1 hppa*-*-osf*
2409 HP/PA Pro target hppa*-*-pro*
2410 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2411 Sequent family i[3456]86-sequent-sysv4*
2412 i[3456]86-sequent-sysv*
2413 i[3456]86-sequent-bsd*
2414 Tsqware Sparclet sparclet-*-*
2415 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2417 * REMOVED configurations and files
2420 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2421 IBM AIX PS/2 i[3456]86-*-aix
2422 i386 running Mach 3.0 i[3456]86-*-mach3*
2423 i386 running Mach i[3456]86-*-mach*
2424 i386 running OSF/1 i[3456]86-*osf1mk*
2425 HP/Apollo 68k Family m68*-apollo*-sysv*,
2427 m68*-hp-bsd*, m68*-hp-hpux*
2428 Argonaut Risc Chip (ARC) arc-*-*
2429 Mitsubishi D30V d30v-*-*
2430 Fujitsu FR30 fr30-*-elf*
2431 OS/9000 i[34]86-*-os9k
2432 I960 with MON960 i960-*-coff
2434 * MIPS $fp behavior changed
2436 The convenience variable $fp, for the MIPS, now consistently returns
2437 the address of the current frame's base. Previously, depending on the
2438 context, $fp could refer to either $sp or the current frame's base
2439 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2440 The GNU Source-Level Debugger''.
2442 *** Changes in GDB 5.3:
2444 * GNU/Linux shared library multi-threaded performance improved.
2446 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2447 `/proc', in preference to `ptrace' for memory reads. This may result
2448 in an improvement in the start-up time of multi-threaded, shared
2449 library applications when run under GDB. One GDB user writes: ``loads
2450 shared libs like mad''.
2452 * ``gdbserver'' now supports multi-threaded applications on some targets
2454 Support for debugging multi-threaded applications which use
2455 the GNU/Linux LinuxThreads package has been added for
2456 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2457 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2459 * GDB now supports C/C++ preprocessor macros.
2461 GDB now expands preprocessor macro invocations in C/C++ expressions,
2462 and provides various commands for showing macro definitions and how
2465 The new command `macro expand EXPRESSION' expands any macro
2466 invocations in expression, and shows the result.
2468 The new command `show macro MACRO-NAME' shows the definition of the
2469 macro named MACRO-NAME, and where it was defined.
2471 Most compilers don't include information about macros in the debugging
2472 information by default. In GCC 3.1, for example, you need to compile
2473 your program with the options `-gdwarf-2 -g3'. If the macro
2474 information is present in the executable, GDB will read it.
2476 * Multi-arched targets.
2478 DEC Alpha (partial) alpha*-*-*
2479 DEC VAX (partial) vax-*-*
2481 National Semiconductor NS32000 (partial) ns32k-*-*
2482 Motorola 68000 (partial) m68k-*-*
2483 Motorola MCORE mcore-*-*
2487 Fujitsu FRV architecture added by Red Hat frv*-*-*
2490 * New native configurations
2492 Alpha NetBSD alpha*-*-netbsd*
2493 SH NetBSD sh*-*-netbsdelf*
2494 MIPS NetBSD mips*-*-netbsd*
2495 UltraSPARC NetBSD sparc64-*-netbsd*
2497 * OBSOLETE configurations and files
2499 Configurations that have been declared obsolete in this release have
2500 been commented out. Unless there is activity to revive these
2501 configurations, the next release of GDB will have their sources
2502 permanently REMOVED.
2504 Mitsubishi D30V d30v-*-*
2505 OS/9000 i[34]86-*-os9k
2506 IBM AIX PS/2 i[3456]86-*-aix
2507 Fujitsu FR30 fr30-*-elf*
2508 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2509 Argonaut Risc Chip (ARC) arc-*-*
2510 i386 running Mach 3.0 i[3456]86-*-mach3*
2511 i386 running Mach i[3456]86-*-mach*
2512 i386 running OSF/1 i[3456]86-*osf1mk*
2513 HP/Apollo 68k Family m68*-apollo*-sysv*,
2515 m68*-hp-bsd*, m68*-hp-hpux*
2516 I960 with MON960 i960-*-coff
2518 * OBSOLETE languages
2520 CHILL, a Pascal like language used by telecommunications companies.
2522 * REMOVED configurations and files
2524 AMD 29k family via UDI a29k-amd-udi, udi29k
2525 A29K VxWorks a29k-*-vxworks
2526 AMD 29000 embedded, using EBMON a29k-none-none
2527 AMD 29000 embedded with COFF a29k-none-coff
2528 AMD 29000 embedded with a.out a29k-none-aout
2530 testsuite/gdb.hp/gdb.threads-hp/ directory
2532 * New command "set max-user-call-depth <nnn>"
2534 This command allows the user to limit the call depth of user-defined
2535 commands. The default is 1024.
2537 * Changes in FreeBSD/i386 native debugging.
2539 Support for the "generate-core-file" has been added.
2541 * New commands "dump", "append", and "restore".
2543 These commands allow data to be copied from target memory
2544 to a bfd-format or binary file (dump and append), and back
2545 from a file into memory (restore).
2547 * Improved "next/step" support on multi-processor Alpha Tru64.
2549 The previous single-step mechanism could cause unpredictable problems,
2550 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2551 of a software single-step mechanism prevents this.
2553 *** Changes in GDB 5.2.1:
2561 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2562 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2563 Fix, by Joel Brobecker imported from mainline.
2565 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2566 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2567 Fix, by Fred Fish, imported from mainline.
2569 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2570 Surprisingly enough, it works now.
2571 By Michal Ludvig, imported from mainline.
2573 i386 hardware watchpoint support:
2574 avoid misses on second run for some targets.
2575 By Pierre Muller, imported from mainline.
2577 *** Changes in GDB 5.2:
2579 * New command "set trust-readonly-sections on[off]".
2581 This command is a hint that tells gdb that read-only sections
2582 really are read-only (ie. that their contents will not change).
2583 In this mode, gdb will go to the object file rather than the
2584 target to read memory from read-only sections (such as ".text").
2585 This can be a significant performance improvement on some
2586 (notably embedded) targets.
2588 * New command "generate-core-file" (or "gcore").
2590 This new gdb command allows the user to drop a core file of the child
2591 process state at any time. So far it's been implemented only for
2592 GNU/Linux and Solaris, but should be relatively easily ported to other
2593 hosts. Argument is core file name (defaults to core.<pid>).
2595 * New command line option
2597 GDB now accepts --pid or -p followed by a process id.
2599 * Change in command line behavior -- corefiles vs. process ids.
2601 There is a subtle behavior in the way in which GDB handles
2602 command line arguments. The first non-flag argument is always
2603 a program to debug, but the second non-flag argument may either
2604 be a corefile or a process id. Previously, GDB would attempt to
2605 open the second argument as a corefile, and if that failed, would
2606 issue a superfluous error message and then attempt to attach it as
2607 a process. Now, if the second argument begins with a non-digit,
2608 it will be treated as a corefile. If it begins with a digit,
2609 GDB will attempt to attach it as a process, and if no such process
2610 is found, will then attempt to open it as a corefile.
2612 * Changes in ARM configurations.
2614 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2615 configuration is fully multi-arch.
2617 * New native configurations
2619 ARM NetBSD arm*-*-netbsd*
2620 x86 OpenBSD i[3456]86-*-openbsd*
2621 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2622 Sparc64 running FreeBSD sparc64-*-freebsd*
2626 Sanyo XStormy16 xstormy16-elf
2628 * OBSOLETE configurations and files
2630 Configurations that have been declared obsolete in this release have
2631 been commented out. Unless there is activity to revive these
2632 configurations, the next release of GDB will have their sources
2633 permanently REMOVED.
2635 AMD 29k family via UDI a29k-amd-udi, udi29k
2636 A29K VxWorks a29k-*-vxworks
2637 AMD 29000 embedded, using EBMON a29k-none-none
2638 AMD 29000 embedded with COFF a29k-none-coff
2639 AMD 29000 embedded with a.out a29k-none-aout
2641 testsuite/gdb.hp/gdb.threads-hp/ directory
2643 * REMOVED configurations and files
2645 TI TMS320C80 tic80-*-*
2647 PowerPC Solaris powerpcle-*-solaris*
2648 PowerPC Windows NT powerpcle-*-cygwin32
2649 PowerPC Netware powerpc-*-netware*
2650 Harris/CXUX m88k m88*-harris-cxux*
2651 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2652 ns32k-utek-sysv* ns32k-utek-*
2653 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2654 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2655 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2656 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2657 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2659 * Changes to command line processing
2661 The new `--args' feature can be used to specify command-line arguments
2662 for the inferior from gdb's command line.
2664 * Changes to key bindings
2666 There is a new `operate-and-get-next' function bound to `C-o'.
2668 *** Changes in GDB 5.1.1
2670 Fix compile problem on DJGPP.
2672 Fix a problem with floating-point registers on the i386 being
2675 Fix to stop GDB crashing on .debug_str debug info.
2677 Numerous documentation fixes.
2679 Numerous testsuite fixes.
2681 *** Changes in GDB 5.1:
2683 * New native configurations
2685 Alpha FreeBSD alpha*-*-freebsd*
2686 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2687 MIPS GNU/Linux mips*-*-linux*
2688 MIPS SGI Irix 6.x mips*-sgi-irix6*
2689 ia64 AIX ia64-*-aix*
2690 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2694 Motorola 68HC11 and 68HC12 m68hc11-elf
2696 UltraSparc running GNU/Linux sparc64-*-linux*
2698 * OBSOLETE configurations and files
2700 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2701 Harris/CXUX m88k m88*-harris-cxux*
2702 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2703 ns32k-utek-sysv* ns32k-utek-*
2704 TI TMS320C80 tic80-*-*
2706 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2707 PowerPC Solaris powerpcle-*-solaris*
2708 PowerPC Windows NT powerpcle-*-cygwin32
2709 PowerPC Netware powerpc-*-netware*
2710 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2711 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2712 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2713 Apple Macintosh (MPW) host N/A
2715 stuff.c (Program to stuff files into a specially prepared space in kdb)
2716 kdb-start.c (Main loop for the standalone kernel debugger)
2718 Configurations that have been declared obsolete in this release have
2719 been commented out. Unless there is activity to revive these
2720 configurations, the next release of GDB will have their sources
2721 permanently REMOVED.
2723 * REMOVED configurations and files
2725 Altos 3068 m68*-altos-*
2726 Convex c1-*-*, c2-*-*
2728 ARM RISCix arm-*-* (as host)
2732 * GDB has been converted to ISO C.
2734 GDB's source code has been converted to ISO C. In particular, the
2735 sources are fully protoized, and rely on standard headers being
2740 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2742 * The MI enabled by default.
2744 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2745 revised and enabled by default. Packages which use GDB as a debugging
2746 engine behind a UI or another front end are encouraged to switch to
2747 using the GDB/MI interface, instead of the old annotations interface
2748 which is now deprecated.
2750 * Support for debugging Pascal programs.
2752 GDB now includes support for debugging Pascal programs. The following
2753 main features are supported:
2755 - Pascal-specific data types such as sets;
2757 - automatic recognition of Pascal sources based on file-name
2760 - Pascal-style display of data types, variables, and functions;
2762 - a Pascal expression parser.
2764 However, some important features are not yet supported.
2766 - Pascal string operations are not supported at all;
2768 - there are some problems with boolean types;
2770 - Pascal type hexadecimal constants are not supported
2771 because they conflict with the internal variables format;
2773 - support for Pascal objects and classes is not full yet;
2775 - unlike Pascal, GDB is case-sensitive for symbol names.
2777 * Changes in completion.
2779 Commands such as `shell', `run' and `set args', which pass arguments
2780 to inferior programs, now complete on file names, similar to what
2781 users expect at the shell prompt.
2783 Commands which accept locations, such as `disassemble', `print',
2784 `breakpoint', `until', etc. now complete on filenames as well as
2785 program symbols. Thus, if you type "break foob TAB", and the source
2786 files linked into the programs include `foobar.c', that file name will
2787 be one of the candidates for completion. However, file names are not
2788 considered for completion after you typed a colon that delimits a file
2789 name from a name of a function in that file, as in "break foo.c:bar".
2791 `set demangle-style' completes on available demangling styles.
2793 * New platform-independent commands:
2795 It is now possible to define a post-hook for a command as well as a
2796 hook that runs before the command. For more details, see the
2797 documentation of `hookpost' in the GDB manual.
2799 * Changes in GNU/Linux native debugging.
2801 Support for debugging multi-threaded programs has been completely
2802 revised for all platforms except m68k and sparc. You can now debug as
2803 many threads as your system allows you to have.
2805 Attach/detach is supported for multi-threaded programs.
2807 Support for SSE registers was added for x86. This doesn't work for
2808 multi-threaded programs though.
2810 * Changes in MIPS configurations.
2812 Multi-arch support is enabled for all MIPS configurations.
2814 GDB can now be built as native debugger on SGI Irix 6.x systems for
2815 debugging n32 executables. (Debugging 64-bit executables is not yet
2818 * Unified support for hardware watchpoints in all x86 configurations.
2820 Most (if not all) native x86 configurations support hardware-assisted
2821 breakpoints and watchpoints in a unified manner. This support
2822 implements debug register sharing between watchpoints, which allows to
2823 put a virtually infinite number of watchpoints on the same address,
2824 and also supports watching regions up to 16 bytes with several debug
2827 The new maintenance command `maintenance show-debug-regs' toggles
2828 debugging print-outs in functions that insert, remove, and test
2829 watchpoints and hardware breakpoints.
2831 * Changes in the DJGPP native configuration.
2833 New command ``info dos sysinfo'' displays assorted information about
2834 the CPU, OS, memory, and DPMI server.
2836 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2837 display information about segment descriptors stored in GDT, LDT, and
2840 New commands ``info dos pde'' and ``info dos pte'' display entries
2841 from Page Directory and Page Tables (for now works with CWSDPMI only).
2842 New command ``info dos address-pte'' displays the Page Table entry for
2843 a given linear address.
2845 GDB can now pass command lines longer than 126 characters to the
2846 program being debugged (requires an update to the libdbg.a library
2847 which is part of the DJGPP development kit).
2849 DWARF2 debug info is now supported.
2851 It is now possible to `step' and `next' through calls to `longjmp'.
2853 * Changes in documentation.
2855 All GDB documentation was converted to GFDL, the GNU Free
2856 Documentation License.
2858 Tracepoints-related commands are now fully documented in the GDB
2861 TUI, the Text-mode User Interface, is now documented in the manual.
2863 Tracepoints-related commands are now fully documented in the GDB
2866 The "GDB Internals" manual now has an index. It also includes
2867 documentation of `ui_out' functions, GDB coding standards, x86
2868 hardware watchpoints, and memory region attributes.
2870 * GDB's version number moved to ``version.in''
2872 The Makefile variable VERSION has been replaced by the file
2873 ``version.in''. People creating GDB distributions should update the
2874 contents of this file.
2878 GUD support is now a standard part of the EMACS distribution.
2880 *** Changes in GDB 5.0:
2882 * Improved support for debugging FP programs on x86 targets
2884 Unified and much-improved support for debugging floating-point
2885 programs on all x86 targets. In particular, ``info float'' now
2886 displays the FP registers in the same format on all x86 targets, with
2887 greater level of detail.
2889 * Improvements and bugfixes in hardware-assisted watchpoints
2891 It is now possible to watch array elements, struct members, and
2892 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2893 on x86 targets no longer erroneously trigger when the address is
2896 * Improvements in the native DJGPP version of GDB
2898 The distribution now includes all the scripts and auxiliary files
2899 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2900 machines ``out of the box''.
2902 The DJGPP version can now debug programs that use signals. It is
2903 possible to catch signals that happened in the debuggee, deliver
2904 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2905 would kill the program being debugged.) Programs that hook hardware
2906 interrupts (keyboard, timer, etc.) can also be debugged.
2908 It is now possible to debug DJGPP programs that redirect their
2909 standard handles or switch them to raw (as opposed to cooked) mode, or
2910 even close them. The command ``run < foo > bar'' works as expected,
2911 and ``info terminal'' reports useful information about the debuggee's
2912 terminal, including raw/cooked mode, redirection, etc.
2914 The DJGPP version now uses termios functions for console I/O, which
2915 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2918 DOS-style file names with drive letters are now fully supported by
2921 It is now possible to debug DJGPP programs that switch their working
2922 directory. It is also possible to rerun the debuggee any number of
2923 times without restarting GDB; thus, you can use the same setup,
2924 breakpoints, etc. for many debugging sessions.
2926 * New native configurations
2928 ARM GNU/Linux arm*-*-linux*
2929 PowerPC GNU/Linux powerpc-*-linux*
2933 Motorola MCore mcore-*-*
2934 x86 VxWorks i[3456]86-*-vxworks*
2935 PowerPC VxWorks powerpc-*-vxworks*
2936 TI TMS320C80 tic80-*-*
2938 * OBSOLETE configurations
2940 Altos 3068 m68*-altos-*
2941 Convex c1-*-*, c2-*-*
2943 ARM RISCix arm-*-* (as host)
2946 Configurations that have been declared obsolete will be commented out,
2947 but the code will be left in place. If there is no activity to revive
2948 these configurations before the next release of GDB, the sources will
2949 be permanently REMOVED.
2951 * Gould support removed
2953 Support for the Gould PowerNode and NP1 has been removed.
2955 * New features for SVR4
2957 On SVR4 native platforms (such as Solaris), if you attach to a process
2958 without first loading a symbol file, GDB will now attempt to locate and
2959 load symbols from the running process's executable file.
2961 * Many C++ enhancements
2963 C++ support has been greatly improved. Overload resolution now works properly
2964 in almost all cases. RTTI support is on the way.
2966 * Remote targets can connect to a sub-program
2968 A popen(3) style serial-device has been added. This device starts a
2969 sub-process (such as a stand-alone simulator) and then communicates
2970 with that. The sub-program to run is specified using the syntax
2971 ``|<program> <args>'' vis:
2973 (gdb) set remotedebug 1
2974 (gdb) target extended-remote |mn10300-elf-sim program-args
2976 * MIPS 64 remote protocol
2978 A long standing bug in the mips64 remote protocol where by GDB
2979 expected certain 32 bit registers (ex SR) to be transfered as 32
2980 instead of 64 bits has been fixed.
2982 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2983 added to provide backward compatibility with older versions of GDB.
2985 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2987 The command ``set remotebinarydownload'' command has been replaced by
2988 ``set remote X-packet''. Other commands in ``set remote'' family
2989 include ``set remote P-packet''.
2991 * Breakpoint commands accept ranges.
2993 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2994 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2995 ``tracepoint passcount'' also accepts a range of tracepoints.
2997 * ``apropos'' command added.
2999 The ``apropos'' command searches through command names and
3000 documentation strings, printing out matches, making it much easier to
3001 try to find a command that does what you are looking for.
3005 A new machine oriented interface (MI) has been added to GDB. This
3006 interface is designed for debug environments running GDB as a separate
3007 process. This is part of the long term libGDB project. See the
3008 "GDB/MI" chapter of the GDB manual for further information. It can be
3009 enabled by configuring with:
3011 .../configure --enable-gdbmi
3013 *** Changes in GDB-4.18:
3015 * New native configurations
3017 HP-UX 10.20 hppa*-*-hpux10.20
3018 HP-UX 11.x hppa*-*-hpux11.0*
3019 M68K GNU/Linux m68*-*-linux*
3023 Fujitsu FR30 fr30-*-elf*
3024 Intel StrongARM strongarm-*-*
3025 Mitsubishi D30V d30v-*-*
3027 * OBSOLETE configurations
3029 Gould PowerNode, NP1 np1-*-*, pn-*-*
3031 Configurations that have been declared obsolete will be commented out,
3032 but the code will be left in place. If there is no activity to revive
3033 these configurations before the next release of GDB, the sources will
3034 be permanently REMOVED.
3038 As a compatibility experiment, GDB's source files buildsym.h and
3039 buildsym.c have been converted to pure standard C, no longer
3040 containing any K&R compatibility code. We believe that all systems in
3041 use today either come with a standard C compiler, or have a GCC port
3042 available. If this is not true, please report the affected
3043 configuration to bug-gdb@gnu.org immediately. See the README file for
3044 information about getting a standard C compiler if you don't have one
3049 GDB now uses readline 2.2.
3051 * set extension-language
3053 You can now control the mapping between filename extensions and source
3054 languages by using the `set extension-language' command. For instance,
3055 you can ask GDB to treat .c files as C++ by saying
3056 set extension-language .c c++
3057 The command `info extensions' lists all of the recognized extensions
3058 and their associated languages.
3060 * Setting processor type for PowerPC and RS/6000
3062 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3063 you can use the `set processor' command to specify what variant of the
3064 PowerPC family you are debugging. The command
3068 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3069 following PowerPC and RS6000 variants:
3071 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3072 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3074 403GC IBM PowerPC 403GC
3075 505 Motorola PowerPC 505
3076 860 Motorola PowerPC 860 or 850
3077 601 Motorola PowerPC 601
3078 602 Motorola PowerPC 602
3079 603 Motorola/IBM PowerPC 603 or 603e
3080 604 Motorola PowerPC 604 or 604e
3081 750 Motorola/IBM PowerPC 750 or 750
3083 At the moment, this command just tells GDB what to name the
3084 special-purpose processor registers. Since almost all the affected
3085 registers are inaccessible to user-level programs, this command is
3086 only useful for remote debugging in its present form.
3090 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3091 more extensive support for HP-UX. Added features include shared
3092 library support, kernel threads and hardware watchpoints for 11.00,
3093 support for HP's ANSI C and C++ compilers, and a compatibility mode
3094 for xdb and dbx commands.
3098 HP's donation includes the new concept of catchpoints, which is a
3099 generalization of the old catch command. On HP-UX, it is now possible
3100 to catch exec, fork, and vfork, as well as library loading.
3102 This means that the existing catch command has changed; its first
3103 argument now specifies the type of catch to be set up. See the
3104 output of "help catch" for a list of catchpoint types.
3106 * Debugging across forks
3108 On HP-UX, you can choose which process to debug when a fork() happens
3113 HP has donated a curses-based terminal user interface (TUI). To get
3114 it, build with --enable-tui. Although this can be enabled for any
3115 configuration, at present it only works for native HP debugging.
3117 * GDB remote protocol additions
3119 A new protocol packet 'X' that writes binary data is now available.
3120 Default behavior is to try 'X', then drop back to 'M' if the stub
3121 fails to respond. The settable variable `remotebinarydownload'
3122 allows explicit control over the use of 'X'.
3124 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3125 full 64-bit address. The command
3127 set remoteaddresssize 32
3129 can be used to revert to the old behaviour. For existing remote stubs
3130 the change should not be noticed, as the additional address information
3133 In order to assist in debugging stubs, you may use the maintenance
3134 command `packet' to send any text string to the stub. For instance,
3136 maint packet heythere
3138 sends the packet "$heythere#<checksum>". Note that it is very easy to
3139 disrupt a debugging session by sending the wrong packet at the wrong
3142 The compare-sections command allows you to compare section data on the
3143 target to what is in the executable file without uploading or
3144 downloading, by comparing CRC checksums.
3146 * Tracing can collect general expressions
3148 You may now collect general expressions at tracepoints. This requires
3149 further additions to the target-side stub; see tracepoint.c and
3150 doc/agentexpr.texi for further details.
3152 * mask-address variable for Mips
3154 For Mips targets, you may control the zeroing of the upper 32 bits of
3155 a 64-bit address by entering `set mask-address on'. This is mainly
3156 of interest to users of embedded R4xxx and R5xxx processors.
3158 * Higher serial baud rates
3160 GDB's serial code now allows you to specify baud rates 57600, 115200,
3161 230400, and 460800 baud. (Note that your host system may not be able
3162 to achieve all of these rates.)
3166 The i960 configuration now includes an initial implementation of a
3167 builtin simulator, contributed by Jim Wilson.
3170 *** Changes in GDB-4.17:
3172 * New native configurations
3174 Alpha GNU/Linux alpha*-*-linux*
3175 Unixware 2.x i[3456]86-unixware2*
3176 Irix 6.x mips*-sgi-irix6*
3177 PowerPC GNU/Linux powerpc-*-linux*
3178 PowerPC Solaris powerpcle-*-solaris*
3179 Sparc GNU/Linux sparc-*-linux*
3180 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3184 Argonaut Risc Chip (ARC) arc-*-*
3185 Hitachi H8/300S h8300*-*-*
3186 Matsushita MN10200 w/simulator mn10200-*-*
3187 Matsushita MN10300 w/simulator mn10300-*-*
3188 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3189 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3190 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3191 Mitsubishi D10V w/simulator d10v-*-*
3192 Mitsubishi M32R/D w/simulator m32r-*-elf*
3193 Tsqware Sparclet sparclet-*-*
3194 NEC V850 w/simulator v850-*-*
3196 * New debugging protocols
3198 ARM with RDI protocol arm*-*-*
3199 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3200 DDB and LSI variants of PMON protocol mips*-*-*
3201 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3202 PowerPC with SDS protocol powerpc{,le}-*-eabi
3203 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3207 All configurations can now understand and use the DWARF 2 debugging
3208 format. The choice is automatic, if the symbol file contains DWARF 2
3213 GDB now includes basic Java language support. This support is
3214 only useful with Java compilers that produce native machine code.
3216 * solib-absolute-prefix and solib-search-path
3218 For SunOS and SVR4 shared libraries, you may now set the prefix for
3219 loading absolute shared library symbol files, and the search path for
3220 locating non-absolute shared library symbol files.
3222 * Live range splitting
3224 GDB can now effectively debug code for which GCC has performed live
3225 range splitting as part of its optimization. See gdb/doc/LRS for
3226 more details on the expected format of the stabs information.
3230 GDB's support for the GNU Hurd, including thread debugging, has been
3231 updated to work with current versions of the Hurd.
3235 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3236 instruction set. ARM GDB automatically detects when Thumb
3237 instructions are in use, and adjusts disassembly and backtracing
3242 GDB's MIPS target configurations now handle the MIP16 16-bit
3247 GDB now includes support for overlays; if an executable has been
3248 linked such that multiple sections are based at the same address, GDB
3249 will decide which section to use for symbolic info. You can choose to
3250 control the decision manually, using overlay commands, or implement
3251 additional target-side support and use "overlay load-target" to bring
3252 in the overlay mapping. Do "help overlay" for more detail.
3256 The command "info symbol <address>" displays information about
3257 the symbol at the specified address.
3261 The standard remote protocol now includes an extension that allows
3262 asynchronous collection and display of trace data. This requires
3263 extensive support in the target-side debugging stub. Tracing mode
3264 includes a new interaction mode in GDB and new commands: see the
3265 file tracepoint.c for more details.
3269 Configurations for embedded MIPS now include a simulator contributed
3270 by Cygnus Solutions. The simulator supports the instruction sets
3271 of most MIPS variants.
3275 Sparc configurations may now include the ERC32 simulator contributed
3276 by the European Space Agency. The simulator is not built into
3277 Sparc targets by default; configure with --enable-sim to include it.
3281 For target configurations that may include multiple variants of a
3282 basic architecture (such as MIPS and SH), you may now set the
3283 architecture explicitly. "set arch" sets, "info arch" lists
3284 the possible architectures.
3286 *** Changes in GDB-4.16:
3288 * New native configurations
3290 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3291 M68K NetBSD m68k-*-netbsd*
3292 PowerPC AIX 4.x powerpc-*-aix*
3293 PowerPC MacOS powerpc-*-macos*
3294 PowerPC Windows NT powerpcle-*-cygwin32
3295 RS/6000 AIX 4.x rs6000-*-aix4*
3299 ARM with RDP protocol arm-*-*
3300 I960 with MON960 i960-*-coff
3301 MIPS VxWorks mips*-*-vxworks*
3302 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3303 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3305 Matra Sparclet sparclet-*-*
3309 The powerpc-eabi configuration now includes the PSIM simulator,
3310 contributed by Andrew Cagney, with assistance from Mike Meissner.
3311 PSIM is a very elaborate model of the PowerPC, including not only
3312 basic instruction set execution, but also details of execution unit
3313 performance and I/O hardware. See sim/ppc/README for more details.
3317 GDB now works with Solaris 2.5.
3319 * Windows 95/NT native
3321 GDB will now work as a native debugger on Windows 95 and Windows NT.
3322 To build it from source, you must use the "gnu-win32" environment,
3323 which uses a DLL to emulate enough of Unix to run the GNU tools.
3324 Further information, binaries, and sources are available at
3325 ftp.cygnus.com, under pub/gnu-win32.
3327 * dont-repeat command
3329 If a user-defined command includes the command `dont-repeat', then the
3330 command will not be repeated if the user just types return. This is
3331 useful if the command is time-consuming to run, so that accidental
3332 extra keystrokes don't run the same command many times.
3334 * Send break instead of ^C
3336 The standard remote protocol now includes an option to send a break
3337 rather than a ^C to the target in order to interrupt it. By default,
3338 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3340 * Remote protocol timeout
3342 The standard remote protocol includes a new variable `remotetimeout'
3343 that allows you to set the number of seconds before GDB gives up trying
3344 to read from the target. The default value is 2.
3346 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3348 By default GDB will automatically keep track of objects as they are
3349 loaded and unloaded by the dynamic linker. By using the command `set
3350 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3351 when shared library events occur, thus allowing you to set breakpoints
3352 in shared libraries which are explicitly loaded by the inferior.
3354 Note this feature does not work on hpux8. On hpux9 you must link
3355 /usr/lib/end.o into your program. This feature should work
3356 automatically on hpux10.
3358 * Irix 5.x hardware watchpoint support
3360 Irix 5 configurations now support the use of hardware watchpoints.
3362 * Mips protocol "SYN garbage limit"
3364 When debugging a Mips target using the `target mips' protocol, you
3365 may set the number of characters that GDB will ignore by setting
3366 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3367 every character. The default value is 1050.
3369 * Recording and replaying remote debug sessions
3371 If you set `remotelogfile' to the name of a file, gdb will write to it
3372 a recording of a remote debug session. This recording may then be
3373 replayed back to gdb using "gdbreplay". See gdbserver/README for
3374 details. This is useful when you have a problem with GDB while doing
3375 remote debugging; you can make a recording of the session and send it
3376 to someone else, who can then recreate the problem.
3378 * Speedups for remote debugging
3380 GDB includes speedups for downloading and stepping MIPS systems using
3381 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3382 and more efficient S-record downloading.
3384 * Memory use reductions and statistics collection
3386 GDB now uses less memory and reports statistics about memory usage.
3387 Try the `maint print statistics' command, for example.
3389 *** Changes in GDB-4.15:
3391 * Psymtabs for XCOFF
3393 The symbol reader for AIX GDB now uses partial symbol tables. This
3394 can greatly improve startup time, especially for large executables.
3396 * Remote targets use caching
3398 Remote targets now use a data cache to speed up communication with the
3399 remote side. The data cache could lead to incorrect results because
3400 it doesn't know about volatile variables, thus making it impossible to
3401 debug targets which use memory mapped I/O devices. `set remotecache
3402 off' turns the the data cache off.
3404 * Remote targets may have threads
3406 The standard remote protocol now includes support for multiple threads
3407 in the target system, using new protocol commands 'H' and 'T'. See
3408 gdb/remote.c for details.
3412 If GDB is configured with `--enable-netrom', then it will include
3413 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3414 acts as though it is a bank of ROM on the target board, but you can
3415 write into it over the network. GDB's support consists only of
3416 support for fast loading into the emulated ROM; to debug, you must use
3417 another protocol, such as standard remote protocol. The usual
3418 sequence is something like
3420 target nrom <netrom-hostname>
3422 target remote <netrom-hostname>:1235
3426 GDB now includes support for the Apple Macintosh, as a host only. It
3427 may be run as either an MPW tool or as a standalone application, and
3428 it can debug through the serial port. All the usual GDB commands are
3429 available, but to the target command, you must supply "serial" as the
3430 device type instead of "/dev/ttyXX". See mpw-README in the main
3431 directory for more information on how to build. The MPW configuration
3432 scripts */mpw-config.in support only a few targets, and only the
3433 mips-idt-ecoff target has been tested.
3437 GDB configuration now uses autoconf. This is not user-visible,
3438 but does simplify configuration and building.
3442 GDB now supports hpux10.
3444 *** Changes in GDB-4.14:
3446 * New native configurations
3448 x86 FreeBSD i[345]86-*-freebsd
3449 x86 NetBSD i[345]86-*-netbsd
3450 NS32k NetBSD ns32k-*-netbsd
3451 Sparc NetBSD sparc-*-netbsd
3455 A29K VxWorks a29k-*-vxworks
3456 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3457 CPU32 EST-300 emulator m68*-*-est*
3458 PowerPC ELF powerpc-*-elf
3461 * Alpha OSF/1 support for procfs
3463 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3464 possible to attach to running processes. As the mounting of the /proc
3465 filesystem is optional on the Alpha, GDB automatically determines
3466 the availability of /proc during startup. This can lead to problems
3467 if /proc is unmounted after GDB has been started.
3469 * Arguments to user-defined commands
3471 User commands may accept up to 10 arguments separated by whitespace.
3472 Arguments are accessed within the user command via $arg0..$arg9. A
3475 print $arg0 + $arg1 + $arg2
3477 To execute the command use:
3480 Defines the command "adder" which prints the sum of its three arguments.
3481 Note the arguments are text substitutions, so they may reference variables,
3482 use complex expressions, or even perform inferior function calls.
3484 * New `if' and `while' commands
3486 This makes it possible to write more sophisticated user-defined
3487 commands. Both commands take a single argument, which is the
3488 expression to evaluate, and must be followed by the commands to
3489 execute, one per line, if the expression is nonzero, the list being
3490 terminated by the word `end'. The `if' command list may include an
3491 `else' word, which causes the following commands to be executed only
3492 if the expression is zero.
3494 * Fortran source language mode
3496 GDB now includes partial support for Fortran 77. It will recognize
3497 Fortran programs and can evaluate a subset of Fortran expressions, but
3498 variables and functions may not be handled correctly. GDB will work
3499 with G77, but does not yet know much about symbols emitted by other
3502 * Better HPUX support
3504 Most debugging facilities now work on dynamic executables for HPPAs
3505 running hpux9 or later. You can attach to running dynamically linked
3506 processes, but by default the dynamic libraries will be read-only, so
3507 for instance you won't be able to put breakpoints in them. To change
3508 that behavior do the following before running the program:
3514 This will cause the libraries to be mapped private and read-write.
3515 To revert to the normal behavior, do this:
3521 You cannot set breakpoints or examine data in the library until after
3522 the library is loaded if the function/data symbols do not have
3525 GDB can now also read debug symbols produced by the HP C compiler on
3526 HPPAs (sorry, no C++, Fortran or 68k support).
3528 * Target byte order now dynamically selectable
3530 You can choose which byte order to use with a target system, via the
3531 commands "set endian big" and "set endian little", and you can see the
3532 current setting by using "show endian". You can also give the command
3533 "set endian auto", in which case GDB will use the byte order
3534 associated with the executable. Currently, only embedded MIPS
3535 configurations support dynamic selection of target byte order.
3537 * New DOS host serial code
3539 This version uses DPMI interrupts to handle buffered I/O, so you
3540 no longer need to run asynctsr when debugging boards connected to
3543 *** Changes in GDB-4.13:
3545 * New "complete" command
3547 This lists all the possible completions for the rest of the line, if it
3548 were to be given as a command itself. This is intended for use by emacs.
3550 * Trailing space optional in prompt
3552 "set prompt" no longer adds a space for you after the prompt you set. This
3553 allows you to set a prompt which ends in a space or one that does not.
3555 * Breakpoint hit counts
3557 "info break" now displays a count of the number of times the breakpoint
3558 has been hit. This is especially useful in conjunction with "ignore"; you
3559 can ignore a large number of breakpoint hits, look at the breakpoint info
3560 to see how many times the breakpoint was hit, then run again, ignoring one
3561 less than that number, and this will get you quickly to the last hit of
3564 * Ability to stop printing at NULL character
3566 "set print null-stop" will cause GDB to stop printing the characters of
3567 an array when the first NULL is encountered. This is useful when large
3568 arrays actually contain only short strings.
3570 * Shared library breakpoints
3572 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3573 breakpoints in shared libraries before the executable is run.
3575 * Hardware watchpoints
3577 There is a new hardware breakpoint for the watch command for sparclite
3578 targets. See gdb/sparclite/hw_breakpoint.note.
3580 Hardware watchpoints are also now supported under GNU/Linux.
3584 Annotations have been added. These are for use with graphical interfaces,
3585 and are still experimental. Currently only gdba.el uses these.
3587 * Improved Irix 5 support
3589 GDB now works properly with Irix 5.2.
3591 * Improved HPPA support
3593 GDB now works properly with the latest GCC and GAS.
3595 * New native configurations
3597 Sequent PTX4 i[34]86-sequent-ptx4
3598 HPPA running OSF/1 hppa*-*-osf*
3599 Atari TT running SVR4 m68*-*-sysv4*
3600 RS/6000 LynxOS rs6000-*-lynxos*
3604 OS/9000 i[34]86-*-os9k
3605 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3608 * Hitachi SH7000 and E7000-PC ICE support
3610 There is now support for communicating with the Hitachi E7000-PC ICE.
3611 This is available automatically when GDB is configured for the SH.
3615 As usual, a variety of small fixes and improvements, both generic
3616 and configuration-specific. See the ChangeLog for more detail.
3618 *** Changes in GDB-4.12:
3620 * Irix 5 is now supported
3624 GDB-4.12 on the HPPA has a number of changes which make it unable
3625 to debug the output from the currently released versions of GCC and
3626 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3627 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3628 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3631 *** Changes in GDB-4.11:
3633 * User visible changes:
3637 The "set remotedebug" option is now consistent between the mips remote
3638 target, remote targets using the gdb-specific protocol, UDI (AMD's
3639 debug protocol for the 29k) and the 88k bug monitor. It is now an
3640 integer specifying a debug level (normally 0 or 1, but 2 means more
3641 debugging info for the mips target).
3643 * DEC Alpha native support
3645 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3646 debug info, but GDB works fairly well with the DEC compiler and should
3647 work with a future GCC release. See the README file for a few
3648 Alpha-specific notes.
3650 * Preliminary thread implementation
3652 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3654 * LynxOS native and target support for 386
3656 This release has been hosted on LynxOS 2.2, and also can be configured
3657 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3660 * Improvements in C++ mangling/demangling.
3662 This release has much better g++ debugging, specifically in name
3663 mangling/demangling, virtual function calls, print virtual table,
3664 call methods, ...etc.
3666 *** Changes in GDB-4.10:
3668 * User visible changes:
3670 Remote debugging using the GDB-specific (`target remote') protocol now
3671 supports the `load' command. This is only useful if you have some
3672 other way of getting the stub to the target system, and you can put it
3673 somewhere in memory where it won't get clobbered by the download.
3675 Filename completion now works.
3677 When run under emacs mode, the "info line" command now causes the
3678 arrow to point to the line specified. Also, "info line" prints
3679 addresses in symbolic form (as well as hex).
3681 All vxworks based targets now support a user settable option, called
3682 vxworks-timeout. This option represents the number of seconds gdb
3683 should wait for responses to rpc's. You might want to use this if
3684 your vxworks target is, perhaps, a slow software simulator or happens
3685 to be on the far side of a thin network line.
3689 This release contains support for using a DEC alpha as a GDB host for
3690 cross debugging. Native alpha debugging is not supported yet.
3693 *** Changes in GDB-4.9:
3697 This is the first GDB release which is accompanied by a matching testsuite.
3698 The testsuite requires installation of dejagnu, which should be available
3699 via ftp from most sites that carry GNU software.
3703 'Cfront' style demangling has had its name changed to 'ARM' style, to
3704 emphasize that it was written from the specifications in the C++ Annotated
3705 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3706 disclaimers, it still generated too much confusion with users attempting to
3707 use gdb with AT&T cfront.
3711 GDB now uses a standard remote interface to a simulator library.
3712 So far, the library contains simulators for the Zilog Z8001/2, the
3713 Hitachi H8/300, H8/500 and Super-H.
3715 * New targets supported
3717 H8/300 simulator h8300-hitachi-hms or h8300hms
3718 H8/500 simulator h8500-hitachi-hms or h8500hms
3719 SH simulator sh-hitachi-hms or sh
3720 Z8000 simulator z8k-zilog-none or z8ksim
3721 IDT MIPS board over serial line mips-idt-ecoff
3723 Cross-debugging to GO32 targets is supported. It requires a custom
3724 version of the i386-stub.c module which is integrated with the
3725 GO32 memory extender.
3727 * New remote protocols
3729 MIPS remote debugging protocol.
3731 * New source languages supported
3733 This version includes preliminary support for Chill, a Pascal like language
3734 used by telecommunications companies. Chill support is also being integrated
3735 into the GNU compiler, but we don't know when it will be publically available.
3738 *** Changes in GDB-4.8:
3740 * HP Precision Architecture supported
3742 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3743 version of this support was available as a set of patches from the
3744 University of Utah. GDB does not support debugging of programs
3745 compiled with the HP compiler, because HP will not document their file
3746 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3747 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3749 Many problems in the preliminary version have been fixed.
3751 * Faster and better demangling
3753 We have improved template demangling and fixed numerous bugs in the GNU style
3754 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3755 character types (wchar_t) are now supported. Demangling of each symbol is now
3756 only done once, and is cached when the symbol table for a file is read in.
3757 This results in a small increase in memory usage for C programs, a moderate
3758 increase in memory usage for C++ programs, and a fantastic speedup in
3761 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3762 from the specifications in the Annotated Reference Manual, which AT&T's
3763 compiler does not actually implement.
3765 * G++ multiple inheritance compiler problem
3767 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3768 inheritance lattices was reworked to properly discover ambiguities. We
3769 recently found an example which causes this new algorithm to fail in a
3770 very subtle way, producing bad debug information for those classes.
3771 The file 'gcc.patch' (in this directory) can be applied to gcc to
3772 circumvent the problem. A future GCC release will contain a complete
3775 The previous G++ debug info problem (mentioned below for the gdb-4.7
3776 release) is fixed in gcc version 2.3.2.
3778 * Improved configure script
3780 The `configure' script will now attempt to guess your system type if
3781 you don't supply a host system type. The old scheme of supplying a
3782 host system triplet is preferable over using this. All the magic is
3783 done in the new `config.guess' script. Examine it for details.
3785 We have also brought our configure script much more in line with the FSF's
3786 version. It now supports the --with-xxx options. In particular,
3787 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3788 The resulting GDB will not be able to read arbitrary object file formats --
3789 only the format ``expected'' to be used on the configured target system.
3790 We hope to make this the default in a future release.
3792 * Documentation improvements
3794 There's new internal documentation on how to modify GDB, and how to
3795 produce clean changes to the code. We implore people to read it
3796 before submitting changes.
3798 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3799 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3800 `info' files are also provided. To build `info' files from scratch,
3801 you will need the latest `makeinfo' release, which will be available in
3802 a future texinfo-X.Y release.
3804 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3805 We're not sure exactly which versions have this problem, but it has
3806 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3807 or better. If that isn't possible, there is a patch in
3808 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3809 around this problem.
3813 GDB now supports array constants that can be used in expressions typed in by
3814 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3815 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3818 The new directory `gdb/sparclite' contains a program that demonstrates
3819 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3821 * New native hosts supported
3823 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3824 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3826 * New targets supported
3828 AMD 29k family via UDI a29k-amd-udi or udi29k
3830 * New file formats supported
3832 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3833 HPUX core files, and SCO 3.2v2 core files.
3837 Attaching to processes now works again; thanks for the many bug reports.
3839 We have also stomped on a bunch of core dumps caused by
3840 printf_filtered("%s") problems.
3842 We eliminated a copyright problem on the rpc and ptrace header files
3843 for VxWorks, which was discovered at the last minute during the 4.7
3844 release. You should now be able to build a VxWorks GDB.
3846 You can now interrupt gdb while an attached process is running. This
3847 will cause the attached process to stop, and give control back to GDB.
3849 We fixed problems caused by using too many file descriptors
3850 for reading symbols from object files and libraries. This was
3851 especially a problem for programs that used many (~100) shared
3854 The `step' command now only enters a subroutine if there is line number
3855 information for the subroutine. Otherwise it acts like the `next'
3856 command. Previously, `step' would enter subroutines if there was
3857 any debugging information about the routine. This avoids problems
3858 when using `cc -g1' on MIPS machines.
3860 * Internal improvements
3862 GDB's internal interfaces have been improved to make it easier to support
3863 debugging of multiple languages in the future.
3865 GDB now uses a common structure for symbol information internally.
3866 Minimal symbols (derived from linkage symbols in object files), partial
3867 symbols (from a quick scan of debug information), and full symbols
3868 contain a common subset of information, making it easier to write
3869 shared code that handles any of them.
3871 * New command line options
3873 We now accept --silent as an alias for --quiet.
3877 The memory-mapped-malloc library is now licensed under the GNU Library
3878 General Public License.
3880 *** Changes in GDB-4.7:
3882 * Host/native/target split
3884 GDB has had some major internal surgery to untangle the support for
3885 hosts and remote targets. Now, when you configure GDB for a remote
3886 target, it will no longer load in all of the support for debugging
3887 local programs on the host. When fully completed and tested, this will
3888 ensure that arbitrary host/target combinations are possible.
3890 The primary conceptual shift is to separate the non-portable code in
3891 GDB into three categories. Host specific code is required any time GDB
3892 is compiled on that host, regardless of the target. Target specific
3893 code relates to the peculiarities of the target, but can be compiled on
3894 any host. Native specific code is everything else: it can only be
3895 built when the host and target are the same system. Child process
3896 handling and core file support are two common `native' examples.
3898 GDB's use of /proc for controlling Unix child processes is now cleaner.
3899 It has been split out into a single module under the `target_ops' vector,
3900 plus two native-dependent functions for each system that uses /proc.
3902 * New hosts supported
3904 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3905 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3906 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3908 * New targets supported
3910 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3911 68030 and CPU32 m68030-*-*, m68332-*-*
3913 * New native hosts supported
3915 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3916 (386bsd is not well tested yet)
3917 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3919 * New file formats supported
3921 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3922 supports reading of `a.out.adobe' object files, which are an a.out
3923 format extended with minimal information about multiple sections.
3927 `show copying' is the same as the old `info copying'.
3928 `show warranty' is the same as `info warrantee'.
3929 These were renamed for consistency. The old commands continue to work.
3931 `info handle' is a new alias for `info signals'.
3933 You can now define pre-command hooks, which attach arbitrary command
3934 scripts to any command. The commands in the hook will be executed
3935 prior to the user's command. You can also create a hook which will be
3936 executed whenever the program stops. See gdb.texinfo.
3940 We now deal with Cfront style name mangling, and can even extract type
3941 info from mangled symbols. GDB can automatically figure out which
3942 symbol mangling style your C++ compiler uses.
3944 Calling of methods and virtual functions has been improved as well.
3948 The crash that occured when debugging Sun Ansi-C compiled binaries is
3949 fixed. This was due to mishandling of the extra N_SO stabs output
3952 We also finally got Ultrix 4.2 running in house, and fixed core file
3953 support, with help from a dozen people on the net.
3955 John M. Farrell discovered that the reason that single-stepping was so
3956 slow on all of the Mips based platforms (primarily SGI and DEC) was
3957 that we were trying to demangle and lookup a symbol used for internal
3958 purposes on every instruction that was being stepped through. Changing
3959 the name of that symbol so that it couldn't be mistaken for a C++
3960 mangled symbol sped things up a great deal.
3962 Rich Pixley sped up symbol lookups in general by getting much smarter
3963 about when C++ symbol mangling is necessary. This should make symbol
3964 completion (TAB on the command line) much faster. It's not as fast as
3965 we'd like, but it's significantly faster than gdb-4.6.
3969 A new user controllable variable 'call_scratch_address' can
3970 specify the location of a scratch area to be used when GDB
3971 calls a function in the target. This is necessary because the
3972 usual method of putting the scratch area on the stack does not work
3973 in systems that have separate instruction and data spaces.
3975 We integrated changes to support the 29k UDI (Universal Debugger
3976 Interface), but discovered at the last minute that we didn't have all
3977 of the appropriate copyright paperwork. We are working with AMD to
3978 resolve this, and hope to have it available soon.
3982 We have sped up the remote serial line protocol, especially for targets
3983 with lots of registers. It now supports a new `expedited status' ('T')
3984 message which can be used in place of the existing 'S' status message.
3985 This allows the remote stub to send only the registers that GDB
3986 needs to make a quick decision about single-stepping or conditional
3987 breakpoints, eliminating the need to fetch the entire register set for
3988 each instruction being stepped through.
3990 The GDB remote serial protocol now implements a write-through cache for
3991 registers, only re-reading the registers if the target has run.
3993 There is also a new remote serial stub for SPARC processors. You can
3994 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3995 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3996 processor with a serial port.
4000 Configure.in files have become much easier to read and modify. A new
4001 `table driven' format makes it more obvious what configurations are
4002 supported, and what files each one uses.
4006 There is a new opcodes library which will eventually contain all of the
4007 disassembly routines and opcode tables. At present, it only contains
4008 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4009 disassembler (binutils/objdump) to share these routines.
4011 The libiberty library is now copylefted under the GNU Library General
4012 Public License. This allows more liberal use, and was done so libg++
4013 can use it. This makes no difference to GDB, since the Library License
4014 grants all the rights from the General Public License.
4018 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4019 reference to the stabs symbol info used by the debugger. It is (as far
4020 as we know) the only published document on this fascinating topic. We
4021 encourage you to read it, compare it to the stabs information on your
4022 system, and send improvements on the document in general (to
4023 bug-gdb@prep.ai.mit.edu).
4025 And, of course, many bugs have been fixed.
4028 *** Changes in GDB-4.6:
4030 * Better support for C++ function names
4032 GDB now accepts as input the "demangled form" of C++ overloaded function
4033 names and member function names, and can do command completion on such names
4034 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4035 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4036 Make use of command completion, it is your friend.
4038 GDB also now accepts a variety of C++ mangled symbol formats. They are
4039 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4040 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4041 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4042 for the list of formats.
4044 * G++ symbol mangling problem
4046 Recent versions of gcc have a bug in how they emit debugging information for
4047 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4048 directory) can be applied to gcc to fix the problem. Alternatively, if you
4049 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4050 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4051 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4054 * New 'maintenance' command
4056 All of the commands related to hacking GDB internals have been moved out of
4057 the main command set, and now live behind the 'maintenance' command. This
4058 can also be abbreviated as 'mt'. The following changes were made:
4060 dump-me -> maintenance dump-me
4061 info all-breakpoints -> maintenance info breakpoints
4062 printmsyms -> maintenance print msyms
4063 printobjfiles -> maintenance print objfiles
4064 printpsyms -> maintenance print psymbols
4065 printsyms -> maintenance print symbols
4067 The following commands are new:
4069 maintenance demangle Call internal GDB demangler routine to
4070 demangle a C++ link name and prints the result.
4071 maintenance print type Print a type chain for a given symbol
4073 * Change to .gdbinit file processing
4075 We now read the $HOME/.gdbinit file before processing the argv arguments
4076 (e.g. reading symbol files or core files). This allows global parameters to
4077 be set, which will apply during the symbol reading. The ./.gdbinit is still
4078 read after argv processing.
4080 * New hosts supported
4082 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4084 GNU/Linux support i386-unknown-linux or linux
4086 We are also including code to support the HP/PA running BSD and HPUX. This
4087 is almost guaranteed not to work, as we didn't have time to test or build it
4088 for this release. We are including it so that the more adventurous (or
4089 masochistic) of you can play with it. We also had major problems with the
4090 fact that the compiler that we got from HP doesn't support the -g option.
4093 * New targets supported
4095 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4097 * More smarts about finding #include files
4099 GDB now remembers the compilation directory for all include files, and for
4100 all files from which C is generated (like yacc and lex sources). This
4101 greatly improves GDB's ability to find yacc/lex sources, and include files,
4102 especially if you are debugging your program from a directory different from
4103 the one that contains your sources.
4105 We also fixed a bug which caused difficulty with listing and setting
4106 breakpoints in include files which contain C code. (In the past, you had to
4107 try twice in order to list an include file that you hadn't looked at before.)
4109 * Interesting infernals change
4111 GDB now deals with arbitrary numbers of sections, where the symbols for each
4112 section must be relocated relative to that section's landing place in the
4113 target's address space. This work was needed to support ELF with embedded
4114 stabs used by Solaris-2.0.
4116 * Bug fixes (of course!)
4118 There have been loads of fixes for the following things:
4119 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4120 i960, stabs, DOS(GO32), procfs, etc...
4122 See the ChangeLog for details.
4124 *** Changes in GDB-4.5:
4126 * New machines supported (host and target)
4128 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4130 SGI Irix-4.x mips-sgi-irix4 or iris4
4132 * New malloc package
4134 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4135 Mmalloc is capable of handling mutiple heaps of memory. It is also
4136 capable of saving a heap to a file, and then mapping it back in later.
4137 This can be used to greatly speedup the startup of GDB by using a
4138 pre-parsed symbol table which lives in a mmalloc managed heap. For
4139 more details, please read mmalloc/mmalloc.texi.
4143 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4144 'help info proc' for details.
4146 * MIPS ecoff symbol table format
4148 The code that reads MIPS symbol table format is now supported on all hosts.
4149 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4152 * File name changes for MS-DOS
4154 Many files in the config directories have been renamed to make it easier to
4155 support GDB on MS-DOSe systems (which have very restrictive file name
4156 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4157 environment) is close to working but has some remaining problems. Note
4158 that debugging of DOS programs is not supported, due to limitations
4159 in the ``operating system'', but it can be used to host cross-debugging.
4161 * Cross byte order fixes
4163 Many fixes have been made to support cross debugging of Sparc and MIPS
4164 targets from hosts whose byte order differs.
4166 * New -mapped and -readnow options
4168 If memory-mapped files are available on your system through the 'mmap'
4169 system call, you can use the -mapped option on the `file' or
4170 `symbol-file' commands to cause GDB to write the symbols from your
4171 program into a reusable file. If the program you are debugging is
4172 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4173 Future GDB debugging sessions will notice the presence of this file,
4174 and will quickly map in symbol information from it, rather than reading
4175 the symbol table from the executable program. Using the '-mapped'
4176 option in a GDB `file' or `symbol-file' command has the same effect as
4177 starting GDB with the '-mapped' command-line option.
4179 You can cause GDB to read the entire symbol table immediately by using
4180 the '-readnow' option with any of the commands that load symbol table
4181 information (or on the GDB command line). This makes the command
4182 slower, but makes future operations faster.
4184 The -mapped and -readnow options are typically combined in order to
4185 build a `fred.syms' file that contains complete symbol information.
4186 A simple GDB invocation to do nothing but build a `.syms' file for future
4189 gdb -batch -nx -mapped -readnow programname
4191 The `.syms' file is specific to the host machine on which GDB is run.
4192 It holds an exact image of GDB's internal symbol table. It cannot be
4193 shared across multiple host platforms.
4195 * longjmp() handling
4197 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4198 siglongjmp() without losing control. This feature has not yet been ported to
4199 all systems. It currently works on many 386 platforms, all MIPS-based
4200 platforms (SGI, DECstation, etc), and Sun3/4.
4204 Preliminary work has been put in to support the new Solaris OS from Sun. At
4205 this time, it can control and debug processes, but it is not capable of
4210 As always, many many bug fixes. The major areas were with g++, and mipsread.
4211 People using the MIPS-based platforms should experience fewer mysterious
4212 crashes and trashed symbol tables.
4214 *** Changes in GDB-4.4:
4216 * New machines supported (host and target)
4218 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4220 BSD Reno on Vax vax-dec-bsd
4221 Ultrix on Vax vax-dec-ultrix
4223 * New machines supported (target)
4225 AMD 29000 embedded, using EBMON a29k-none-none
4229 GDB continues to improve its handling of C++. `References' work better.
4230 The demangler has also been improved, and now deals with symbols mangled as
4231 per the Annotated C++ Reference Guide.
4233 GDB also now handles `stabs' symbol information embedded in MIPS
4234 `ecoff' symbol tables. Since the ecoff format was not easily
4235 extensible to handle new languages such as C++, this appeared to be a
4236 good way to put C++ debugging info into MIPS binaries. This option
4237 will be supported in the GNU C compiler, version 2, when it is
4240 * New features for SVR4
4242 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4243 shared libraries. Debugging dynamically linked programs should present
4244 only minor differences from debugging statically linked programs.
4246 The `info proc' command will print out information about any process
4247 on an SVR4 system (including the one you are debugging). At the moment,
4248 it prints the address mappings of the process.
4250 If you bring up GDB on another SVR4 system, please send mail to
4251 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4253 * Better dynamic linking support in SunOS
4255 Reading symbols from shared libraries which contain debugging symbols
4256 now works properly. However, there remain issues such as automatic
4257 skipping of `transfer vector' code during function calls, which
4258 make it harder to debug code in a shared library, than to debug the
4259 same code linked statically.
4263 GDB is now using the latest `getopt' routines from the FSF. This
4264 version accepts the -- prefix for options with long names. GDB will
4265 continue to accept the old forms (-option and +option) as well.
4266 Various single letter abbreviations for options have been explicity
4267 added to the option table so that they won't get overshadowed in the
4268 future by other options that begin with the same letter.
4272 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4273 Many assorted bugs have been handled. Many more remain to be handled.
4274 See the various ChangeLog files (primarily in gdb and bfd) for details.
4277 *** Changes in GDB-4.3:
4279 * New machines supported (host and target)
4281 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4282 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4283 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4285 * Almost SCO Unix support
4287 We had hoped to support:
4288 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4289 (except for core file support), but we discovered very late in the release
4290 that it has problems with process groups that render gdb unusable. Sorry
4291 about that. I encourage people to fix it and post the fixes.
4293 * Preliminary ELF and DWARF support
4295 GDB can read ELF object files on System V Release 4, and can handle
4296 debugging records for C, in DWARF format, in ELF files. This support
4297 is preliminary. If you bring up GDB on another SVR4 system, please
4298 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4303 GDB now uses the latest `readline' library. One user-visible change
4304 is that two tabs will list possible command completions, which previously
4305 required typing M-? (meta-question mark, or ESC ?).
4309 The `stepi' bug that many of you noticed has been squashed.
4310 Many bugs in C++ have been handled. Many more remain to be handled.
4311 See the various ChangeLog files (primarily in gdb and bfd) for details.
4313 * State of the MIPS world (in case you wondered):
4315 GDB can understand the symbol tables emitted by the compilers
4316 supplied by most vendors of MIPS-based machines, including DEC. These
4317 symbol tables are in a format that essentially nobody else uses.
4319 Some versions of gcc come with an assembler post-processor called
4320 mips-tfile. This program is required if you want to do source-level
4321 debugging of gcc-compiled programs. I believe FSF does not ship
4322 mips-tfile with gcc version 1, but it will eventually come with gcc
4325 Debugging of g++ output remains a problem. g++ version 1.xx does not
4326 really support it at all. (If you're lucky, you should be able to get
4327 line numbers and stack traces to work, but no parameters or local
4328 variables.) With some work it should be possible to improve the
4331 When gcc version 2 is released, you will have somewhat better luck.
4332 However, even then you will get confusing results for inheritance and
4335 We will eventually provide full debugging of g++ output on
4336 DECstations. This will probably involve some kind of stabs-in-ecoff
4337 encapulation, but the details have not been worked out yet.
4340 *** Changes in GDB-4.2:
4342 * Improved configuration
4344 Only one copy of `configure' exists now, and it is not self-modifying.
4345 Porting BFD is simpler.
4349 The `step' and `next' commands now only stop at the first instruction
4350 of a source line. This prevents the multiple stops that used to occur
4351 in switch statements, for-loops, etc. `Step' continues to stop if a
4352 function that has debugging information is called within the line.
4356 Lots of small bugs fixed. More remain.
4358 * New host supported (not target)
4360 Intel 386 PC clone running Mach i386-none-mach
4363 *** Changes in GDB-4.1:
4365 * Multiple source language support
4367 GDB now has internal scaffolding to handle several source languages.
4368 It determines the type of each source file from its filename extension,
4369 and will switch expression parsing and number formatting to match the
4370 language of the function in the currently selected stack frame.
4371 You can also specifically set the language to be used, with
4372 `set language c' or `set language modula-2'.
4376 GDB now has preliminary support for the GNU Modula-2 compiler,
4377 currently under development at the State University of New York at
4378 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4379 continue through the fall of 1991 and into 1992.
4381 Other Modula-2 compilers are currently not supported, and attempting to
4382 debug programs compiled with them will likely result in an error as the
4383 symbol table is read. Feel free to work on it, though!
4385 There are hooks in GDB for strict type checking and range checking,
4386 in the `Modula-2 philosophy', but they do not currently work.
4390 GDB can now write to executable and core files (e.g. patch
4391 a variable's value). You must turn this switch on, specify
4392 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4393 by assigning a new value to a variable. Modifications take
4396 * Automatic SunOS shared library reading
4398 When you run your program, GDB automatically determines where its
4399 shared libraries (if any) have been loaded, and reads their symbols.
4400 The `share' command is no longer needed. This also works when
4401 examining core files.
4405 You can specify the number of lines that the `list' command shows.
4408 * New machines supported (host and target)
4410 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4411 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4412 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4414 * New hosts supported (not targets)
4416 IBM RT/PC: romp-ibm-aix or rtpc
4418 * New targets supported (not hosts)
4420 AMD 29000 embedded with COFF a29k-none-coff
4421 AMD 29000 embedded with a.out a29k-none-aout
4422 Ultracomputer remote kernel debug a29k-nyu-kern
4424 * New remote interfaces
4430 *** Changes in GDB-4.0:
4434 Wide output is wrapped at good places to make the output more readable.
4436 Gdb now supports cross-debugging from a host machine of one type to a
4437 target machine of another type. Communication with the target system
4438 is over serial lines. The ``target'' command handles connecting to the
4439 remote system; the ``load'' command will download a program into the
4440 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4441 also supports debugging of realtime processes running under VxWorks,
4442 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4443 stub on the target system.
4445 New CPUs supported include the AMD 29000 and Intel 960.
4447 GDB now reads object files and symbol tables via a ``binary file''
4448 library, which allows a single copy of GDB to debug programs of multiple
4449 object file types such as a.out and coff.
4451 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4452 refcard.dvi and refcard.ps are available to format it).
4455 * Control-Variable user interface simplified
4457 All variables that control the operation of the debugger can be set
4458 by the ``set'' command, and displayed by the ``show'' command.
4460 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4461 ``Show prompt'' produces the response:
4462 Gdb's prompt is new-gdb=>.
4464 What follows are the NEW set commands. The command ``help set'' will
4465 print a complete list of old and new set commands. ``help set FOO''
4466 will give a longer description of the variable FOO. ``show'' will show
4467 all of the variable descriptions and their current settings.
4469 confirm on/off: Enables warning questions for operations that are
4470 hard to recover from, e.g. rerunning the program while
4471 it is already running. Default is ON.
4473 editing on/off: Enables EMACS style command line editing
4474 of input. Previous lines can be recalled with
4475 control-P, the current line can be edited with control-B,
4476 you can search for commands with control-R, etc.
4479 history filename NAME: NAME is where the gdb command history
4480 will be stored. The default is .gdb_history,
4481 or the value of the environment variable
4484 history size N: The size, in commands, of the command history. The
4485 default is 256, or the value of the environment variable
4488 history save on/off: If this value is set to ON, the history file will
4489 be saved after exiting gdb. If set to OFF, the
4490 file will not be saved. The default is OFF.
4492 history expansion on/off: If this value is set to ON, then csh-like
4493 history expansion will be performed on
4494 command line input. The default is OFF.
4496 radix N: Sets the default radix for input and output. It can be set
4497 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4498 in the current radix, so "set radix 10" is always a no-op.
4500 height N: This integer value is the number of lines on a page. Default
4501 is 24, the current `stty rows'' setting, or the ``li#''
4502 setting from the termcap entry matching the environment
4505 width N: This integer value is the number of characters on a line.
4506 Default is 80, the current `stty cols'' setting, or the ``co#''
4507 setting from the termcap entry matching the environment
4510 Note: ``set screensize'' is obsolete. Use ``set height'' and
4511 ``set width'' instead.
4513 print address on/off: Print memory addresses in various command displays,
4514 such as stack traces and structure values. Gdb looks
4515 more ``symbolic'' if you turn this off; it looks more
4516 ``machine level'' with it on. Default is ON.
4518 print array on/off: Prettyprint arrays. New convenient format! Default
4521 print demangle on/off: Print C++ symbols in "source" form if on,
4524 print asm-demangle on/off: Same, for assembler level printouts
4527 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4530 * Support for Epoch Environment.
4532 The epoch environment is a version of Emacs v18 with windowing. One
4533 new command, ``inspect'', is identical to ``print'', except that if you
4534 are running in the epoch environment, the value is printed in its own
4538 * Support for Shared Libraries
4540 GDB can now debug programs and core files that use SunOS shared libraries.
4541 Symbols from a shared library cannot be referenced
4542 before the shared library has been linked with the program (this
4543 happens after you type ``run'' and before the function main() is entered).
4544 At any time after this linking (including when examining core files
4545 from dynamically linked programs), gdb reads the symbols from each
4546 shared library when you type the ``sharedlibrary'' command.
4547 It can be abbreviated ``share''.
4549 sharedlibrary REGEXP: Load shared object library symbols for files
4550 matching a unix regular expression. No argument
4551 indicates to load symbols for all shared libraries.
4553 info sharedlibrary: Status of loaded shared libraries.
4558 A watchpoint stops execution of a program whenever the value of an
4559 expression changes. Checking for this slows down execution
4560 tremendously whenever you are in the scope of the expression, but is
4561 quite useful for catching tough ``bit-spreader'' or pointer misuse
4562 problems. Some machines such as the 386 have hardware for doing this
4563 more quickly, and future versions of gdb will use this hardware.
4565 watch EXP: Set a watchpoint (breakpoint) for an expression.
4567 info watchpoints: Information about your watchpoints.
4569 delete N: Deletes watchpoint number N (same as breakpoints).
4570 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4571 enable N: Re-enables watchpoint number N (same as breakpoints).
4574 * C++ multiple inheritance
4576 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4579 * C++ exception handling
4581 Gdb now supports limited C++ exception handling. Besides the existing
4582 ability to breakpoint on an exception handler, gdb can breakpoint on
4583 the raising of an exception (before the stack is peeled back to the
4586 catch FOO: If there is a FOO exception handler in the dynamic scope,
4587 set a breakpoint to catch exceptions which may be raised there.
4588 Multiple exceptions (``catch foo bar baz'') may be caught.
4590 info catch: Lists all exceptions which may be caught in the
4591 current stack frame.
4594 * Minor command changes
4596 The command ``call func (arg, arg, ...)'' now acts like the print
4597 command, except it does not print or save a value if the function's result
4598 is void. This is similar to dbx usage.
4600 The ``up'' and ``down'' commands now always print the frame they end up
4601 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4602 frames without printing.
4604 * New directory command
4606 'dir' now adds directories to the FRONT of the source search path.
4607 The path starts off empty. Source files that contain debug information
4608 about the directory in which they were compiled can be found even
4609 with an empty path; Sun CC and GCC include this information. If GDB can't
4610 find your source file in the current directory, type "dir .".
4612 * Configuring GDB for compilation
4614 For normal use, type ``./configure host''. See README or gdb.texinfo
4617 GDB now handles cross debugging. If you are remotely debugging between
4618 two different machines, type ``./configure host -target=targ''.
4619 Host is the machine where GDB will run; targ is the machine
4620 where the program that you are debugging will run.