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 ** Type objects for struct and union types now allow access to
45 the fields using standard Python dictionary (mapping) methods.
46 For example, "some_type['myfield']" now works, as does
49 ** A new event "gdb.new_objfile" has been added, triggered by loading a
52 * libthread-db-search-path now supports two special values: $sdir and $pdir.
53 $sdir specifies the default system locations of shared libraries.
54 $pdir specifies the directory where the libpthread used by the application
57 GDB no longer looks in $sdir and $pdir after it has searched the directories
58 mentioned in libthread-db-search-path. If you want to search those
59 directories, they must be specified in libthread-db-search-path.
60 The default value of libthread-db-search-path on GNU/Linux and Solaris
61 systems is now "$sdir:$pdir".
63 $pdir is not supported by gdbserver, it is currently ignored.
64 $sdir is supported by gdbserver.
66 * New configure option --with-iconv-bin.
67 When using the internationalization support like the one in the GNU C
68 library, GDB will invoke the "iconv" program to get a list of supported
69 character sets. If this program lives in a non-standard location, one can
70 use this option to specify where to find it.
72 * When natively debugging programs on PowerPC BookE processors running
73 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
74 watchpoints, which specify a mask in addition to an address to watch.
75 The mask specifies that some bits of an address (the bits which are
76 reset in the mask) should be ignored when matching the address accessed
77 by the inferior against the watchpoint address. See the "PowerPC Embedded"
78 section in the user manual for more details.
80 * The new option --once causes GDBserver to stop listening for connections once
81 the first connection is made. The listening port used by GDBserver will
82 become available after that.
84 * New commands "info macros", and "info definitions" have been added.
88 watch EXPRESSION mask MASK_VALUE
89 The watch command now supports the mask argument which allows creation
90 of masked watchpoints, if the current architecture supports this feature.
92 info auto-load-scripts [REGEXP]
93 This command was formerly named "maintenance print section-scripts".
94 It is now generally useful and is no longer a maintenance-only command.
96 * Tracepoints can now be enabled and disabled at any time after a trace
97 experiment has been started using the standard "enable" and "disable"
98 commands. It is now possible to start a trace experiment with no enabled
99 tracepoints; GDB will display a warning, but will allow the experiment to
100 begin, assuming that tracepoints will be enabled as needed while the trace
107 Dynamically enable a tracepoint in a started trace experiment.
111 Dynamically disable a tracepoint in a started trace experiment.
113 * Dcache size (number of lines) and line-size are now runtime-configurable
114 via "set dcache line" and "set dcache line-size" commands.
118 Texas Instruments TMS320C6x tic6x-*-*
120 *** Changes in GDB 7.3.1
122 * The build failure for NetBSD and OpenBSD targets have now been fixed.
124 *** Changes in GDB 7.3
126 * GDB has a new command: "thread find [REGEXP]".
127 It finds the thread id whose name, target id, or thread extra info
128 matches the given regular expression.
130 * The "catch syscall" command now works on mips*-linux* targets.
132 * The -data-disassemble MI command now supports modes 2 and 3 for
133 dumping the instruction opcodes.
135 * New command line options
137 -data-directory DIR Specify DIR as the "data-directory".
138 This is mostly for testing purposes.
140 * The "maint set python auto-load on|off" command has been renamed to
141 "set auto-load-scripts on|off".
143 * GDB has a new command: "set directories".
144 It is like the "dir" command except that it replaces the
145 source path list instead of augmenting it.
147 * GDB now understands thread names.
149 On GNU/Linux, "info threads" will display the thread name as set by
150 prctl or pthread_setname_np.
152 There is also a new command, "thread name", which can be used to
153 assign a name internally for GDB to display.
156 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
157 has been integrated into GDB.
161 ** The function gdb.Write now accepts an optional keyword 'stream'.
162 This keyword, when provided, will direct the output to either
163 stdout, stderr, or GDB's logging output.
165 ** Parameters can now be be sub-classed in Python, and in particular
166 you may implement the get_set_doc and get_show_doc functions.
167 This improves how Parameter set/show documentation is processed
168 and allows for more dynamic content.
170 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
171 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
172 have an is_valid method.
174 ** Breakpoints can now be sub-classed in Python, and in particular
175 you may implement a 'stop' function that is executed each time
176 the inferior reaches that breakpoint.
178 ** New function gdb.lookup_global_symbol looks up a global symbol.
180 ** GDB values in Python are now callable if the value represents a
181 function. For example, if 'some_value' represents a function that
182 takes two integer parameters and returns a value, you can call
183 that function like so:
185 result = some_value (10,20)
187 ** Module gdb.types has been added.
188 It contains a collection of utilities for working with gdb.Types objects:
189 get_basic_type, has_field, make_enum_dict.
191 ** Module gdb.printing has been added.
192 It contains utilities for writing and registering pretty-printers.
193 New classes: PrettyPrinter, SubPrettyPrinter,
194 RegexpCollectionPrettyPrinter.
195 New function: register_pretty_printer.
197 ** New commands "info pretty-printers", "enable pretty-printer" and
198 "disable pretty-printer" have been added.
200 ** gdb.parameter("directories") is now available.
202 ** New function gdb.newest_frame returns the newest frame in the
205 ** The gdb.InferiorThread class has a new "name" attribute. This
206 holds the thread's name.
208 ** Python Support for Inferior events.
209 Python scripts can add observers to be notified of events
210 occurring in the process being debugged.
211 The following events are currently supported:
212 - gdb.events.cont Continue event.
213 - gdb.events.exited Inferior exited event.
214 - gdb.events.stop Signal received, and Breakpoint hit events.
218 ** GDB now puts template parameters in scope when debugging in an
219 instantiation. For example, if you have:
221 template<int X> int func (void) { return X; }
223 then if you step into func<5>, "print X" will show "5". This
224 feature requires proper debuginfo support from the compiler; it
225 was added to GCC 4.5.
227 ** The motion commands "next", "finish", "until", and "advance" now
228 work better when exceptions are thrown. In particular, GDB will
229 no longer lose control of the inferior; instead, the GDB will
230 stop the inferior at the point at which the exception is caught.
231 This functionality requires a change in the exception handling
232 code that was introduced in GCC 4.5.
234 * GDB now follows GCC's rules on accessing volatile objects when
235 reading or writing target state during expression evaluation.
236 One notable difference to prior behavior is that "print x = 0"
237 no longer generates a read of x; the value of the assignment is
238 now always taken directly from the value being assigned.
240 * GDB now has some support for using labels in the program's source in
241 linespecs. For instance, you can use "advance label" to continue
242 execution to a label.
244 * GDB now has support for reading and writing a new .gdb_index
245 section. This section holds a fast index of DWARF debugging
246 information and can be used to greatly speed up GDB startup and
247 operation. See the documentation for `save gdb-index' for details.
249 * The "watch" command now accepts an optional "-location" argument.
250 When used, this causes GDB to watch the memory referred to by the
251 expression. Such a watchpoint is never deleted due to it going out
254 * GDB now supports thread debugging of core dumps on GNU/Linux.
256 GDB now activates thread debugging using the libthread_db library
257 when debugging GNU/Linux core dumps, similarly to when debugging
258 live processes. As a result, when debugging a core dump file, GDB
259 is now able to display pthread_t ids of threads. For example, "info
260 threads" shows the same output as when debugging the process when it
261 was live. In earlier releases, you'd see something like this:
264 * 1 LWP 6780 main () at main.c:10
266 While now you see this:
269 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
271 It is also now possible to inspect TLS variables when debugging core
274 When debugging a core dump generated on a machine other than the one
275 used to run GDB, you may need to point GDB at the correct
276 libthread_db library with the "set libthread-db-search-path"
277 command. See the user manual for more details on this command.
279 * When natively debugging programs on PowerPC BookE processors running
280 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
281 which stop execution of the inferior whenever it executes an instruction
282 at any address within the specified range. See the "PowerPC Embedded"
283 section in the user manual for more details.
285 * New features in the GDB remote stub, GDBserver
287 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
288 and i686 LynxOS (version 5.x).
290 ** GDBserver is now supported on Blackfin Linux.
292 * New native configurations
294 ia64 HP-UX ia64-*-hpux*
298 Analog Devices, Inc. Blackfin Processor bfin-*
300 * Ada task switching is now supported on sparc-elf targets when
301 debugging a program using the Ravenscar Profile. For more information,
302 see the "Tasking Support when using the Ravenscar Profile" section
303 in the GDB user manual.
305 * Guile support was removed.
307 * New features in the GNU simulator
309 ** The --map-info flag lists all known core mappings.
311 ** CFI flashes may be simulated via the "cfi" device.
313 *** Changes in GDB 7.2
315 * Shared library support for remote targets by default
317 When GDB is configured for a generic, non-OS specific target, like
318 for example, --target=arm-eabi or one of the many *-*-elf targets,
319 GDB now queries remote stubs for loaded shared libraries using the
320 `qXfer:libraries:read' packet. Previously, shared library support
321 was always disabled for such configurations.
325 ** Argument Dependent Lookup (ADL)
327 In C++ ADL lookup directs function search to the namespaces of its
328 arguments even if the namespace has not been imported.
338 Here the compiler will search for `foo' in the namespace of 'b'
339 and find A::foo. GDB now supports this. This construct is commonly
340 used in the Standard Template Library for operators.
342 ** Improved User Defined Operator Support
344 In addition to member operators, GDB now supports lookup of operators
345 defined in a namespace and imported with a `using' directive, operators
346 defined in the global scope, operators imported implicitly from an
347 anonymous namespace, and the ADL operators mentioned in the previous
349 GDB now also supports proper overload resolution for all the previously
350 mentioned flavors of operators.
352 ** static const class members
354 Printing of static const class members that are initialized in the
355 class definition has been fixed.
357 * Windows Thread Information Block access.
359 On Windows targets, GDB now supports displaying the Windows Thread
360 Information Block (TIB) structure. This structure is visible either
361 by using the new command `info w32 thread-information-block' or, by
362 dereferencing the new convenience variable named `$_tlb', a
363 thread-specific pointer to the TIB. This feature is also supported
364 when remote debugging using GDBserver.
368 Static tracepoints are calls in the user program into a tracing
369 library. One such library is a port of the LTTng kernel tracer to
370 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
371 When debugging with GDBserver, GDB now supports combining the GDB
372 tracepoint machinery with such libraries. For example: the user can
373 use GDB to probe a static tracepoint marker (a call from the user
374 program into the tracing library) with the new "strace" command (see
375 "New commands" below). This creates a "static tracepoint" in the
376 breakpoint list, that can be manipulated with the same feature set
377 as fast and regular tracepoints. E.g., collect registers, local and
378 global variables, collect trace state variables, and define
379 tracepoint conditions. In addition, the user can collect extra
380 static tracepoint marker specific data, by collecting the new
381 $_sdata internal variable. When analyzing the trace buffer, you can
382 inspect $_sdata like any other variable available to GDB. For more
383 information, see the "Tracepoints" chapter in GDB user manual. New
384 remote packets have been defined to support static tracepoints, see
385 the "New remote packets" section below.
387 * Better reconstruction of tracepoints after disconnected tracing
389 GDB will attempt to download the original source form of tracepoint
390 definitions when starting a trace run, and then will upload these
391 upon reconnection to the target, resulting in a more accurate
392 reconstruction of the tracepoints that are in use on the target.
396 You can now exercise direct control over the ways that GDB can
397 affect your program. For instance, you can disallow the setting of
398 breakpoints, so that the program can run continuously (assuming
399 non-stop mode). In addition, the "observer" variable is available
400 to switch all of the different controls; in observer mode, GDB
401 cannot affect the target's behavior at all, which is useful for
402 tasks like diagnosing live systems in the field.
404 * The new convenience variable $_thread holds the number of the
411 Return the address of the Windows Thread Information Block of a given thread.
415 In response to several of the tracepoint packets, the target may now
416 also respond with a number of intermediate `qRelocInsn' request
417 packets before the final result packet, to have GDB handle
418 relocating an instruction to execute at a different address. This
419 is particularly useful for stubs that support fast tracepoints. GDB
420 reports support for this feature in the qSupported packet.
424 List static tracepoint markers in the target program.
428 List static tracepoint markers at a given address in the target
431 qXfer:statictrace:read
433 Read the static trace data collected (by a `collect $_sdata'
434 tracepoint action). The remote stub reports support for this packet
435 to gdb's qSupported query.
439 Send the current settings of GDB's permission flags.
443 Send part of the source (textual) form of a tracepoint definition,
444 which includes location, conditional, and action list.
446 * The source command now accepts a -s option to force searching for the
447 script in the source search path even if the script name specifies
450 * New features in the GDB remote stub, GDBserver
452 - GDBserver now support tracepoints (including fast tracepoints, and
453 static tracepoints). The feature is currently supported by the
454 i386-linux and amd64-linux builds. See the "Tracepoints support
455 in gdbserver" section in the manual for more information.
457 GDBserver JIT compiles the tracepoint's conditional agent
458 expression bytecode into native code whenever possible for low
459 overhead dynamic tracepoints conditionals. For such tracepoints,
460 an expression that examines program state is evaluated when the
461 tracepoint is reached, in order to determine whether to capture
462 trace data. If the condition is simple and false, processing the
463 tracepoint finishes very quickly and no data is gathered.
465 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
466 for static tracepoints support.
468 - GDBserver now supports x86_64 Windows 64-bit debugging.
470 * GDB now sends xmlRegisters= in qSupported packet to indicate that
471 it understands register description.
473 * The --batch flag now disables pagination and queries.
475 * X86 general purpose registers
477 GDB now supports reading/writing byte, word and double-word x86
478 general purpose registers directly. This means you can use, say,
479 $ah or $ax to refer, respectively, to the byte register AH and
480 16-bit word register AX that are actually portions of the 32-bit
481 register EAX or 64-bit register RAX.
483 * The `commands' command now accepts a range of breakpoints to modify.
484 A plain `commands' following a command that creates multiple
485 breakpoints affects all the breakpoints set by that command. This
486 applies to breakpoints set by `rbreak', and also applies when a
487 single `break' command creates multiple breakpoints (e.g.,
488 breakpoints on overloaded c++ functions).
490 * The `rbreak' command now accepts a filename specification as part of
491 its argument, limiting the functions selected by the regex to those
492 in the specified file.
494 * Support for remote debugging Windows and SymbianOS shared libraries
495 from Unix hosts has been improved. Non Windows GDB builds now can
496 understand target reported file names that follow MS-DOS based file
497 system semantics, such as file names that include drive letters and
498 use the backslash character as directory separator. This makes it
499 possible to transparently use the "set sysroot" and "set
500 solib-search-path" on Unix hosts to point as host copies of the
501 target's shared libraries. See the new command "set
502 target-file-system-kind" described below, and the "Commands to
503 specify files" section in the user manual for more information.
507 eval template, expressions...
508 Convert the values of one or more expressions under the control
509 of the string template to a command line, and call it.
511 set target-file-system-kind unix|dos-based|auto
512 show target-file-system-kind
513 Set or show the assumed file system kind for target reported file
516 save breakpoints <filename>
517 Save all current breakpoint definitions to a file suitable for use
518 in a later debugging session. To read the saved breakpoint
519 definitions, use the `source' command.
521 `save tracepoints' is a new alias for `save-tracepoints'. The latter
524 info static-tracepoint-markers
525 Display information about static tracepoint markers in the target.
527 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
528 Define a static tracepoint by probing a marker at the given
529 function, line, address, or marker ID.
533 Enable and disable observer mode.
535 set may-write-registers on|off
536 set may-write-memory on|off
537 set may-insert-breakpoints on|off
538 set may-insert-tracepoints on|off
539 set may-insert-fast-tracepoints on|off
540 set may-interrupt on|off
541 Set individual permissions for GDB effects on the target. Note that
542 some of these settings can have undesirable or surprising
543 consequences, particularly when changed in the middle of a session.
544 For instance, disabling the writing of memory can prevent
545 breakpoints from being inserted, cause single-stepping to fail, or
546 even crash your program, if you disable after breakpoints have been
547 inserted. However, GDB should not crash.
549 set record memory-query on|off
550 show record memory-query
551 Control whether to stop the inferior if memory changes caused
552 by an instruction cannot be recorded.
557 The disassemble command now supports "start,+length" form of two arguments.
561 ** GDB now provides a new directory location, called the python directory,
562 where Python scripts written for GDB can be installed. The location
563 of that directory is <data-directory>/python, where <data-directory>
564 is the GDB data directory. For more details, see section `Scripting
565 GDB using Python' in the manual.
567 ** The GDB Python API now has access to breakpoints, symbols, symbol
568 tables, program spaces, inferiors, threads and frame's code blocks.
569 Additionally, GDB Parameters can now be created from the API, and
570 manipulated via set/show in the CLI.
572 ** New functions gdb.target_charset, gdb.target_wide_charset,
573 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
575 ** New exception gdb.GdbError.
577 ** Pretty-printers are now also looked up in the current program space.
579 ** Pretty-printers can now be individually enabled and disabled.
581 ** GDB now looks for names of Python scripts to auto-load in a
582 special section named `.debug_gdb_scripts', in addition to looking
583 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
585 * Tracepoint actions were unified with breakpoint commands. In particular,
586 there are no longer differences in "info break" output for breakpoints and
587 tracepoints and the "commands" command can be used for both tracepoints and
592 ARM Symbian arm*-*-symbianelf*
594 * D language support.
595 GDB now supports debugging programs written in the D programming
598 * GDB now supports the extended ptrace interface for PowerPC which is
599 available since Linux kernel version 2.6.34. This automatically enables
600 any hardware breakpoints and additional hardware watchpoints available in
601 the processor. The old ptrace interface exposes just one hardware
602 watchpoint and no hardware breakpoints.
604 * GDB is now able to use the Data Value Compare (DVC) register available on
605 embedded PowerPC processors to implement in hardware simple watchpoint
606 conditions of the form:
608 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
610 This works in native GDB running on Linux kernels with the extended ptrace
611 interface mentioned above.
613 *** Changes in GDB 7.1
619 GDB now supports importing of namespaces in C++. This enables the
620 user to inspect variables from imported namespaces. Support for
621 namepace aliasing has also been added. So, if a namespace is
622 aliased in the current scope (e.g. namepace C=A; ) the user can
623 print variables using the alias (e.g. (gdb) print C::x).
627 All known bugs relating to the printing of virtual base class were
628 fixed. It is now possible to call overloaded static methods using a
633 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
634 and reinterpret_cast<> are now handled by the C++ expression parser.
638 Xilinx MicroBlaze microblaze-*-*
643 Xilinx MicroBlaze microblaze
646 * Multi-program debugging.
648 GDB now has support for multi-program (a.k.a. multi-executable or
649 multi-exec) debugging. This allows for debugging multiple inferiors
650 simultaneously each running a different program under the same GDB
651 session. See "Debugging Multiple Inferiors and Programs" in the
652 manual for more information. This implied some user visible changes
653 in the multi-inferior support. For example, "info inferiors" now
654 lists inferiors that are not running yet or that have exited
655 already. See also "New commands" and "New options" below.
657 * New tracing features
659 GDB's tracepoint facility now includes several new features:
661 ** Trace state variables
663 GDB tracepoints now include support for trace state variables, which
664 are variables managed by the target agent during a tracing
665 experiment. They are useful for tracepoints that trigger each
666 other, so for instance one tracepoint can count hits in a variable,
667 and then a second tracepoint has a condition that is true when the
668 count reaches a particular value. Trace state variables share the
669 $-syntax of GDB convenience variables, and can appear in both
670 tracepoint actions and condition expressions. Use the "tvariable"
671 command to create, and "info tvariables" to view; see "Trace State
672 Variables" in the manual for more detail.
676 GDB now includes an option for defining fast tracepoints, which
677 targets may implement more efficiently, such as by installing a jump
678 into the target agent rather than a trap instruction. The resulting
679 speedup can be by two orders of magnitude or more, although the
680 tradeoff is that some program locations on some target architectures
681 might not allow fast tracepoint installation, for instance if the
682 instruction to be replaced is shorter than the jump. To request a
683 fast tracepoint, use the "ftrace" command, with syntax identical to
684 the regular trace command.
686 ** Disconnected tracing
688 It is now possible to detach GDB from the target while it is running
689 a trace experiment, then reconnect later to see how the experiment
690 is going. In addition, a new variable disconnected-tracing lets you
691 tell the target agent whether to continue running a trace if the
692 connection is lost unexpectedly.
696 GDB now has the ability to save the trace buffer into a file, and
697 then use that file as a target, similarly to you can do with
698 corefiles. You can select trace frames, print data that was
699 collected in them, and use tstatus to display the state of the
700 tracing run at the moment that it was saved. To create a trace
701 file, use "tsave <filename>", and to use it, do "target tfile
704 ** Circular trace buffer
706 You can ask the target agent to handle the trace buffer as a
707 circular buffer, discarding the oldest trace frames to make room for
708 newer ones, by setting circular-trace-buffer to on. This feature may
709 not be available for all target agents.
714 The disassemble command, when invoked with two arguments, now requires
715 the arguments to be comma-separated.
718 The info variables command now displays variable definitions. Files
719 which only declare a variable are not shown.
722 The source command is now capable of sourcing Python scripts.
723 This feature is dependent on the debugger being build with Python
726 Related to this enhancement is also the introduction of a new command
727 "set script-extension" (see below).
729 * New commands (for set/show, see "New options" below)
731 record save [<FILENAME>]
732 Save a file (in core file format) containing the process record
733 execution log for replay debugging at a later time.
735 record restore <FILENAME>
736 Restore the process record execution log that was saved at an
737 earlier time, for replay debugging.
739 add-inferior [-copies <N>] [-exec <FILENAME>]
742 clone-inferior [-copies <N>] [ID]
743 Make a new inferior ready to execute the same program another
749 maint info program-spaces
750 List the program spaces loaded into GDB.
752 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
753 show remote interrupt-sequence
754 Allow the user to select one of ^C, a BREAK signal or BREAK-g
755 as the sequence to the remote target in order to interrupt the execution.
756 Ctrl-C is a default. Some system prefers BREAK which is high level of
757 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
758 Magic SysRq g. It is BREAK signal and character 'g'.
760 set remote interrupt-on-connect [on | off]
761 show remote interrupt-on-connect
762 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
763 remote target when gdb connects to it. This is needed when you debug
766 set remotebreak [on | off]
768 Deprecated. Use "set/show remote interrupt-sequence" instead.
770 tvariable $NAME [ = EXP ]
771 Create or modify a trace state variable.
774 List trace state variables and their values.
776 delete tvariable $NAME ...
777 Delete one or more trace state variables.
780 Evaluate the given expressions without collecting anything into the
781 trace buffer. (Valid in tracepoint actions only.)
783 ftrace FN / FILE:LINE / *ADDR
784 Define a fast tracepoint at the given function, line, or address.
786 * New expression syntax
788 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
789 GDB now parses 0b101010 identically with 42.
793 set follow-exec-mode new|same
794 show follow-exec-mode
795 Control whether GDB reuses the same inferior across an exec call or
796 creates a new one. This is useful to be able to restart the old
797 executable after the inferior having done an exec call.
799 set default-collect EXPR, ...
801 Define a list of expressions to be collected at each tracepoint.
802 This is a useful way to ensure essential items are not overlooked,
803 such as registers or a critical global variable.
805 set disconnected-tracing
806 show disconnected-tracing
807 If set to 1, the target is instructed to continue tracing if it
808 loses its connection to GDB. If 0, the target is to stop tracing
811 set circular-trace-buffer
812 show circular-trace-buffer
813 If set to on, the target is instructed to use a circular trace buffer
814 and discard the oldest trace frames instead of stopping the trace due
815 to a full trace buffer. If set to off, the trace stops when the buffer
816 fills up. Some targets may not support this.
818 set script-extension off|soft|strict
819 show script-extension
820 If set to "off", the debugger does not perform any script language
821 recognition, and all sourced files are assumed to be GDB scripts.
822 If set to "soft" (the default), files are sourced according to
823 filename extension, falling back to GDB scripts if the first
825 If set to "strict", files are sourced according to filename extension.
827 set ada trust-PAD-over-XVS on|off
828 show ada trust-PAD-over-XVS
829 If off, activate a workaround against a bug in the debugging information
830 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
831 the GCC sources for more information about the GNAT encoding and
832 PAD types in particular). It is always safe to set this option to
833 off, but this introduces a slight performance penalty. The default
836 * Python API Improvements
838 ** GDB provides the new class gdb.LazyString. This is useful in
839 some pretty-printing cases. The new method gdb.Value.lazy_string
840 provides a simple way to create objects of this type.
842 ** The fields returned by gdb.Type.fields now have an
843 `is_base_class' attribute.
845 ** The new method gdb.Type.range returns the range of an array type.
847 ** The new method gdb.parse_and_eval can be used to parse and
848 evaluate an expression.
853 Define a trace state variable.
856 Get the current value of a trace state variable.
859 Set desired tracing behavior upon disconnection.
862 Set the trace buffer to be linear or circular.
865 Get data about the tracepoints currently in use.
869 Process record now works correctly with hardware watchpoints.
871 Multiple bug fixes have been made to the mips-irix port, making it
872 much more reliable. In particular:
873 - Debugging threaded applications is now possible again. Previously,
874 GDB would hang while starting the program, or while waiting for
875 the program to stop at a breakpoint.
876 - Attaching to a running process no longer hangs.
877 - An error occurring while loading a core file has been fixed.
878 - Changing the value of the PC register now works again. This fixes
879 problems observed when using the "jump" command, or when calling
880 a function from GDB, or even when assigning a new value to $pc.
881 - With the "finish" and "return" commands, the return value for functions
882 returning a small array is now correctly printed.
883 - It is now possible to break on shared library code which gets executed
884 during a shared library init phase (code executed while executing
885 their .init section). Previously, the breakpoint would have no effect.
886 - GDB is now able to backtrace through the signal handler for
887 non-threaded programs.
889 PIE (Position Independent Executable) programs debugging is now supported.
890 This includes debugging execution of PIC (Position Independent Code) shared
891 libraries although for that, it should be possible to run such libraries as an
894 *** Changes in GDB 7.0
896 * GDB now has an interface for JIT compilation. Applications that
897 dynamically generate code can create symbol files in memory and register
898 them with GDB. For users, the feature should work transparently, and
899 for JIT developers, the interface is documented in the GDB manual in the
900 "JIT Compilation Interface" chapter.
902 * Tracepoints may now be conditional. The syntax is as for
903 breakpoints; either an "if" clause appended to the "trace" command,
904 or the "condition" command is available. GDB sends the condition to
905 the target for evaluation using the same bytecode format as is used
906 for tracepoint actions.
908 * The disassemble command now supports: an optional /r modifier, print the
909 raw instructions in hex as well as in symbolic form, and an optional /m
910 modifier to print mixed source+assembly.
912 * Process record and replay
914 In a architecture environment that supports ``process record and
915 replay'', ``process record and replay'' target can record a log of
916 the process execution, and replay it with both forward and reverse
919 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
920 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
921 set execution-direction {forward|reverse}, for targets that support
924 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
925 feature is available with a native GDB running on kernel version
928 * GDB now has support for multi-byte and wide character sets on the
929 target. Strings whose character type is wchar_t, char16_t, or
930 char32_t are now correctly printed. GDB supports wide- and unicode-
931 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
932 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
933 `printf'. This feature requires iconv to work properly; if your
934 system does not have a working iconv, GDB can use GNU libiconv. See
935 the installation instructions for more information.
937 * GDB now supports automatic retrieval of shared library files from
938 remote targets. To use this feature, specify a system root that begins
939 with the `remote:' prefix, either via the `set sysroot' command or via
940 the `--with-sysroot' configure-time option.
942 * "info sharedlibrary" now takes an optional regex of libraries to show,
943 and it now reports if a shared library has no debugging information.
945 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
946 now complete on file names.
948 * When completing in expressions, gdb will attempt to limit
949 completions to allowable structure or union fields, where appropriate.
950 For instance, consider:
952 # struct example { int f1; double f2; };
953 # struct example variable;
956 If the user types TAB at the end of this command line, the available
957 completions will be "f1" and "f2".
959 * Inlined functions are now supported. They show up in backtraces, and
960 the "step", "next", and "finish" commands handle them automatically.
962 * GDB now supports the token-splicing (##) and stringification (#)
963 operators when expanding macros. It also supports variable-arity
966 * GDB now supports inspecting extra signal information, exported by
967 the new $_siginfo convenience variable. The feature is currently
968 implemented on linux ARM, i386 and amd64.
970 * GDB can now display the VFP floating point registers and NEON vector
971 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
972 can provide these registers (requires Linux 2.6.30 or later). Remote
973 and simulator targets may also provide them.
978 Search memory for a sequence of bytes.
981 Turn off `+'/`-' protocol acknowledgments to permit more efficient
982 operation over reliable transport links. Use of this packet is
983 controlled by the `set remote noack-packet' command.
986 Kill the process with the specified process ID. Use this in preference
987 to `k' when multiprocess protocol extensions are supported.
990 Obtains additional operating system information
994 Read or write additional signal information.
996 * Removed remote protocol undocumented extension
998 An undocumented extension to the remote protocol's `S' stop reply
999 packet that permited the stub to pass a process id was removed.
1000 Remote servers should use the `T' stop reply packet instead.
1002 * GDB now supports multiple function calling conventions according to the
1003 DWARF-2 DW_AT_calling_convention function attribute.
1005 * The SH target utilizes the aforementioned change to distinguish between gcc
1006 and Renesas calling convention. It also adds the new CLI commands
1007 `set/show sh calling-convention'.
1009 * GDB can now read compressed debug sections, as produced by GNU gold
1010 with the --compress-debug-sections=zlib flag.
1012 * 64-bit core files are now supported on AIX.
1014 * Thread switching is now supported on Tru64.
1016 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1017 which will be allocated using malloc later in program execution.
1019 * The qXfer:libraries:read remote procotol packet now allows passing a
1020 list of section offsets.
1022 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1023 conditions handling signals delivered during attach or thread creation
1024 have also been fixed.
1026 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1027 From the user's standpoint, all unqualified instances of True and False
1028 are treated as the standard definitions, regardless of context.
1030 * GDB now parses C++ symbol and type names more flexibly. For
1033 template<typename T> class C { };
1036 GDB will now correctly handle all of:
1038 ptype C<char const *>
1039 ptype C<char const*>
1040 ptype C<const char *>
1041 ptype C<const char*>
1043 * New features in the GDB remote stub, gdbserver
1045 - The "--wrapper" command-line argument tells gdbserver to use a
1046 wrapper program to launch programs for debugging.
1048 - On PowerPC and S/390 targets, it is now possible to use a single
1049 gdbserver executable to debug both 32-bit and 64-bit programs.
1050 (This requires gdbserver itself to be built as a 64-bit executable.)
1052 - gdbserver uses the new noack protocol mode for TCP connections to
1053 reduce communications latency, if also supported and enabled in GDB.
1055 - Support for the sparc64-linux-gnu target is now included in
1058 - The amd64-linux build of gdbserver now supports debugging both
1059 32-bit and 64-bit programs.
1061 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1062 now support hardware watchpoints, and will use them automatically
1067 GDB now has support for scripting using Python. Whether this is
1068 available is determined at configure time.
1070 New GDB commands can now be written in Python.
1072 * Ada tasking support
1074 Ada tasks can now be inspected in GDB. The following commands have
1078 Print the list of Ada tasks.
1080 Print detailed information about task number N.
1082 Print the task number of the current task.
1084 Switch the context of debugging to task number N.
1086 * Support for user-defined prefixed commands. The "define" command can
1087 add new commands to existing prefixes, e.g. "target".
1089 * Multi-inferior, multi-process debugging.
1091 GDB now has generalized support for multi-inferior debugging. See
1092 "Debugging Multiple Inferiors" in the manual for more information.
1093 Although availability still depends on target support, the command
1094 set is more uniform now. The GNU/Linux specific multi-forks support
1095 has been migrated to this new framework. This implied some user
1096 visible changes; see "New commands" and also "Removed commands"
1099 * Target descriptions can now describe the target OS ABI. See the
1100 "Target Description Format" section in the user manual for more
1103 * Target descriptions can now describe "compatible" architectures
1104 to indicate that the target can execute applications for a different
1105 architecture in addition to those for the main target architecture.
1106 See the "Target Description Format" section in the user manual for
1109 * Multi-architecture debugging.
1111 GDB now includes general supports for debugging applications on
1112 hybrid systems that use more than one single processor architecture
1113 at the same time. Each such hybrid architecture still requires
1114 specific support to be added. The only hybrid architecture supported
1115 in this version of GDB is the Cell Broadband Engine.
1117 * GDB now supports integrated debugging of Cell/B.E. applications that
1118 use both the PPU and SPU architectures. To enable support for hybrid
1119 Cell/B.E. debugging, you need to configure GDB to support both the
1120 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1121 --enable-targets configure option.
1123 * Non-stop mode debugging.
1125 For some targets, GDB now supports an optional mode of operation in
1126 which you can examine stopped threads while other threads continue
1127 to execute freely. This is referred to as non-stop mode, with the
1128 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1129 section in the user manual for more information.
1131 To be able to support remote non-stop debugging, a remote stub needs
1132 to implement the non-stop mode remote protocol extensions, as
1133 described in the "Remote Non-Stop" section of the user manual. The
1134 GDB remote stub, gdbserver, has been adjusted to support these
1135 extensions on linux targets.
1137 * New commands (for set/show, see "New options" below)
1139 catch syscall [NAME(S) | NUMBER(S)]
1140 Catch system calls. Arguments, which should be names of system
1141 calls or their numbers, mean catch only those syscalls. Without
1142 arguments, every syscall will be caught. When the inferior issues
1143 any of the specified syscalls, GDB will stop and announce the system
1144 call, both when it is called and when its call returns. This
1145 feature is currently available with a native GDB running on the
1146 Linux Kernel, under the following architectures: x86, x86_64,
1147 PowerPC and PowerPC64.
1149 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1151 Search memory for a sequence of bytes.
1153 maint set python print-stack
1154 maint show python print-stack
1155 Show a stack trace when an error is encountered in a Python script.
1158 Invoke CODE by passing it to the Python interpreter.
1163 These allow macros to be defined, undefined, and listed
1167 Show operating system information about processes.
1170 List the inferiors currently under GDB's control.
1173 Switch focus to inferior number NUM.
1176 Detach from inferior number NUM.
1179 Kill inferior number NUM.
1183 set spu stop-on-load
1184 show spu stop-on-load
1185 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1187 set spu auto-flush-cache
1188 show spu auto-flush-cache
1189 Control whether to automatically flush the software-managed cache
1190 during Cell/B.E. debugging.
1192 set sh calling-convention
1193 show sh calling-convention
1194 Control the calling convention used when calling SH target functions.
1197 show debug timestamp
1198 Control display of timestamps with GDB debugging output.
1200 set disassemble-next-line
1201 show disassemble-next-line
1202 Control display of disassembled source lines or instructions when
1205 set remote noack-packet
1206 show remote noack-packet
1207 Set/show the use of remote protocol QStartNoAckMode packet. See above
1208 under "New remote packets."
1210 set remote query-attached-packet
1211 show remote query-attached-packet
1212 Control use of remote protocol `qAttached' (query-attached) packet.
1214 set remote read-siginfo-object
1215 show remote read-siginfo-object
1216 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1219 set remote write-siginfo-object
1220 show remote write-siginfo-object
1221 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1224 set remote reverse-continue
1225 show remote reverse-continue
1226 Control use of remote protocol 'bc' (reverse-continue) packet.
1228 set remote reverse-step
1229 show remote reverse-step
1230 Control use of remote protocol 'bs' (reverse-step) packet.
1232 set displaced-stepping
1233 show displaced-stepping
1234 Control displaced stepping mode. Displaced stepping is a way to
1235 single-step over breakpoints without removing them from the debuggee.
1236 Also known as "out-of-line single-stepping".
1239 show debug displaced
1240 Control display of debugging info for displaced stepping.
1242 maint set internal-error
1243 maint show internal-error
1244 Control what GDB does when an internal error is detected.
1246 maint set internal-warning
1247 maint show internal-warning
1248 Control what GDB does when an internal warning is detected.
1253 Use a wrapper program to launch programs for debugging.
1255 set multiple-symbols (all|ask|cancel)
1256 show multiple-symbols
1257 The value of this variable can be changed to adjust the debugger behavior
1258 when an expression or a breakpoint location contains an ambiguous symbol
1259 name (an overloaded function name, for instance).
1261 set breakpoint always-inserted
1262 show breakpoint always-inserted
1263 Keep breakpoints always inserted in the target, as opposed to inserting
1264 them when resuming the target, and removing them when the target stops.
1265 This option can improve debugger performance on slow remote targets.
1267 set arm fallback-mode (arm|thumb|auto)
1268 show arm fallback-mode
1269 set arm force-mode (arm|thumb|auto)
1271 These commands control how ARM GDB determines whether instructions
1272 are ARM or Thumb. The default for both settings is auto, which uses
1273 the current CPSR value for instructions without symbols; previous
1274 versions of GDB behaved as if "set arm fallback-mode arm".
1276 set disable-randomization
1277 show disable-randomization
1278 Standalone programs run with the virtual address space randomization enabled
1279 by default on some platforms. This option keeps the addresses stable across
1280 multiple debugging sessions.
1284 Control whether other threads are stopped or not when some thread hits
1289 Requests that asynchronous execution is enabled in the target, if available.
1290 In this case, it's possible to resume target in the background, and interact
1291 with GDB while the target is running. "show target-async" displays the
1292 current state of asynchronous execution of the target.
1294 set target-wide-charset
1295 show target-wide-charset
1296 The target-wide-charset is the name of the character set that GDB
1297 uses when printing characters whose type is wchar_t.
1299 set tcp auto-retry (on|off)
1301 set tcp connect-timeout
1302 show tcp connect-timeout
1303 These commands allow GDB to retry failed TCP connections to a remote stub
1304 with a specified timeout period; this is useful if the stub is launched
1305 in parallel with GDB but may not be ready to accept connections immediately.
1307 set libthread-db-search-path
1308 show libthread-db-search-path
1309 Control list of directories which GDB will search for appropriate
1312 set schedule-multiple (on|off)
1313 show schedule-multiple
1314 Allow GDB to resume all threads of all processes or only threads of
1315 the current process.
1319 Use more aggressive caching for accesses to the stack. This improves
1320 performance of remote debugging (particularly backtraces) without
1321 affecting correctness.
1323 set interactive-mode (on|off|auto)
1324 show interactive-mode
1325 Control whether GDB runs in interactive mode (on) or not (off).
1326 When in interactive mode, GDB waits for the user to answer all
1327 queries. Otherwise, GDB does not wait and assumes the default
1328 answer. When set to auto (the default), GDB determines which
1329 mode to use based on the stdin settings.
1334 For program forks, this is replaced by the new more generic `info
1335 inferiors' command. To list checkpoints, you can still use the
1336 `info checkpoints' command, which was an alias for the `info forks'
1340 Replaced by the new `inferior' command. To switch between
1341 checkpoints, you can still use the `restart' command, which was an
1342 alias for the `fork' command.
1345 This is removed, since some targets don't have a notion of
1346 processes. To switch between processes, you can still use the
1347 `inferior' command using GDB's own inferior number.
1350 For program forks, this is replaced by the new more generic `kill
1351 inferior' command. To delete a checkpoint, you can still use the
1352 `delete checkpoint' command, which was an alias for the `delete
1356 For program forks, this is replaced by the new more generic `detach
1357 inferior' command. To detach a checkpoint, you can still use the
1358 `detach checkpoint' command, which was an alias for the `detach
1361 * New native configurations
1363 x86/x86_64 Darwin i[34567]86-*-darwin*
1365 x86_64 MinGW x86_64-*-mingw*
1369 Lattice Mico32 lm32-*
1370 x86 DICOS i[34567]86-*-dicos*
1371 x86_64 DICOS x86_64-*-dicos*
1374 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1375 (mingw32ce) debugging.
1381 These commands were actually not implemented on any target.
1383 *** Changes in GDB 6.8
1385 * New native configurations
1387 NetBSD/hppa hppa*-*netbsd*
1388 Xtensa GNU/Linux xtensa*-*-linux*
1392 NetBSD/hppa hppa*-*-netbsd*
1393 Xtensa GNU/Lunux xtensa*-*-linux*
1395 * Change in command line behavior -- corefiles vs. process ids.
1397 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1398 attaching to process NUMBER fails, GDB no longer attempts to open a
1399 core file named NUMBER. Attaching to a program using the -c option
1400 is no longer supported. Instead, use the '-p' or '--pid' options.
1402 * GDB can now be built as a native debugger for debugging Windows x86
1403 (mingw32) Portable Executable (PE) programs.
1405 * Pending breakpoints no longer change their number when their address
1408 * GDB now supports breakpoints with multiple locations,
1409 including breakpoints on C++ constructors, inside C++ templates,
1410 and in inlined functions.
1412 * GDB's ability to debug optimized code has been improved. GDB more
1413 accurately identifies function bodies and lexical blocks that occupy
1414 more than one contiguous range of addresses.
1416 * Target descriptions can now describe registers for PowerPC.
1418 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1419 registers on PowerPC targets.
1421 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1422 targets even when the libthread_db library is not available.
1424 * The GDB remote stub, gdbserver, now supports the new file transfer
1425 commands (remote put, remote get, and remote delete).
1427 * The GDB remote stub, gdbserver, now supports run and attach in
1428 extended-remote mode.
1430 * hppa*64*-*-hpux11* target broken
1431 The debugger is unable to start a program and fails with the following
1432 error: "Error trying to get information about dynamic linker".
1433 The gdb-6.7 release is also affected.
1435 * GDB now supports the --enable-targets= configure option to allow
1436 building a single GDB executable that supports multiple remote
1437 target architectures.
1439 * GDB now supports debugging C and C++ programs which use the
1440 Decimal Floating Point extension. In addition, the PowerPC target
1441 now has a set of pseudo-registers to inspect decimal float values
1442 stored in two consecutive float registers.
1444 * The -break-insert MI command can optionally create pending
1447 * Improved support for debugging Ada
1448 Many improvements to the Ada language support have been made. These
1450 - Better support for Ada2005 interface types
1451 - Improved handling of arrays and slices in general
1452 - Better support for Taft-amendment types
1453 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1455 - Improved command completion in Ada
1458 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1463 set print frame-arguments (all|scalars|none)
1464 show print frame-arguments
1465 The value of this variable can be changed to control which argument
1466 values should be printed by the debugger when displaying a frame.
1471 Transfer files to and from a remote target, and delete remote files.
1478 Transfer files to and from a remote target, and delete remote files.
1480 * New remote packets
1487 Open, close, read, write, and delete files on the remote system.
1490 Attach to an existing process on the remote system, in extended-remote
1494 Run a new process on the remote system, in extended-remote mode.
1496 *** Changes in GDB 6.7
1498 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1499 bfd, libiberty and opcodes, as revealed by static analysis donated by
1500 Coverity, Inc. (http://scan.coverity.com).
1502 * When looking up multiply-defined global symbols, GDB will now prefer the
1503 symbol definition in the current shared library if it was built using the
1504 -Bsymbolic linker option.
1506 * When the Text User Interface (TUI) is not configured, GDB will now
1507 recognize the -tui command-line option and print a message that the TUI
1510 * The GDB remote stub, gdbserver, now has lower overhead for high
1511 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1513 * GDB for MIPS targets now autodetects whether a remote target provides
1514 32-bit or 64-bit register values.
1516 * Support for C++ member pointers has been improved.
1518 * GDB now understands XML target descriptions, which specify the
1519 target's overall architecture. GDB can read a description from
1520 a local file or over the remote serial protocol.
1522 * Vectors of single-byte data use a new integer type which is not
1523 automatically displayed as character or string data.
1525 * The /s format now works with the print command. It displays
1526 arrays of single-byte integers and pointers to single-byte integers
1529 * Target descriptions can now describe target-specific registers,
1530 for architectures which have implemented the support (currently
1531 only ARM, M68K, and MIPS).
1533 * GDB and the GDB remote stub, gdbserver, now support the XScale
1536 * The GDB remote stub, gdbserver, has been updated to support
1537 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1538 has been rewritten to use the standard GDB remote protocol.
1540 * GDB can now step into C++ functions which are called through thunks.
1542 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1544 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1545 layout. It also supports a TextSeg= and DataSeg= response when only
1546 segment base addresses (rather than offsets) are available.
1548 * The /i format now outputs any trailing branch delay slot instructions
1549 immediately following the last instruction within the count specified.
1551 * The GDB remote protocol "T" stop reply packet now supports a
1552 "library" response. Combined with the new "qXfer:libraries:read"
1553 packet, this response allows GDB to debug shared libraries on targets
1554 where the operating system manages the list of loaded libraries (e.g.
1555 Windows and SymbianOS).
1557 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1558 (DLLs) on Windows and Windows CE targets.
1560 * GDB now supports a faster verification that a .debug file matches its binary
1561 according to its build-id signature, if the signature is present.
1567 Enable or disable hardware flow control (RTS/CTS) on the serial port
1568 when debugging using remote targets.
1570 set mem inaccessible-by-default
1571 show mem inaccessible-by-default
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 prevents GDB from accessing memory outside the memory map. This
1575 is useful for targets with memory mapped registers or which react
1576 badly to accesses of unmapped address space.
1578 set breakpoint auto-hw
1579 show breakpoint auto-hw
1580 If the target supplies a memory map, for instance via the remote
1581 protocol's "qXfer:memory-map:read" packet, setting this variable
1582 lets GDB use hardware breakpoints automatically for memory regions
1583 where it can not use software breakpoints. This covers both the
1584 "break" command and internal breakpoints used for other commands
1585 including "next" and "finish".
1588 catch exception unhandled
1589 Stop the program execution when Ada exceptions are raised.
1592 Stop the program execution when an Ada assertion failed.
1596 Set an alternate system root for target files. This is a more
1597 general version of "set solib-absolute-prefix", which is now
1598 an alias to "set sysroot".
1601 Provide extended SPU facility status information. This set of
1602 commands is available only when debugging the Cell/B.E. SPU
1605 * New native configurations
1607 OpenBSD/sh sh*-*openbsd*
1610 unset tdesc filename
1612 Use the specified local file as an XML target description, and do
1613 not query the target for its built-in description.
1617 OpenBSD/sh sh*-*-openbsd*
1618 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1619 Toshiba Media Processor mep-elf
1621 * New remote packets
1624 Ignore the specified signals; pass them directly to the debugged program
1625 without stopping other threads or reporting them to GDB.
1627 qXfer:features:read:
1628 Read an XML target description from the target, which describes its
1633 Read or write contents of an spufs file on the target system. These
1634 packets are available only on the Cell/B.E. SPU architecture.
1636 qXfer:libraries:read:
1637 Report the loaded shared libraries. Combined with new "T" packet
1638 response, this packet allows GDB to debug shared libraries on
1639 targets where the operating system manages the list of loaded
1640 libraries (e.g. Windows and SymbianOS).
1644 Support for these obsolete configurations has been removed.
1652 i[34567]86-*-lynxos*
1653 i[34567]86-*-netware*
1654 i[34567]86-*-sco3.2v5*
1655 i[34567]86-*-sco3.2v4*
1657 i[34567]86-*-sysv4.2*
1660 i[34567]86-*-unixware2*
1661 i[34567]86-*-unixware*
1670 * Other removed features
1677 Various m68k-only ROM monitors.
1684 Various Renesas ROM monitors and debugging interfaces for SH and
1689 Support for a Macraigor serial interface to on-chip debugging.
1690 GDB does not directly support the newer parallel or USB
1695 A debug information format. The predecessor to DWARF 2 and
1696 DWARF 3, which are still supported.
1698 Support for the HP aCC compiler on HP-UX/PA-RISC
1700 SOM-encapsulated symbolic debugging information, automatic
1701 invocation of pxdb, and the aCC custom C++ ABI. This does not
1702 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1703 with aCC can still be debugged on an assembly level.
1705 MIPS ".pdr" sections
1707 A MIPS-specific format used to describe stack frame layout
1708 in debugging information.
1712 GDB could work with an older version of Guile to debug
1713 the interpreter and Scheme programs running in it.
1715 set mips stack-arg-size
1716 set mips saved-gpreg-size
1718 Use "set mips abi" to control parameter passing for MIPS.
1720 *** Changes in GDB 6.6
1725 Cell Broadband Engine SPU spu-elf
1727 * GDB can now be configured as a cross-debugger targeting native Windows
1728 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1729 running on a Windows system over TCP/IP to debug Windows programs.
1731 * The GDB remote stub, gdbserver, has been updated to support Windows and
1732 Cygwin debugging. Both single-threaded and multi-threaded programs are
1735 * The "set trust-readonly-sections" command works again. This command was
1736 broken in GDB 6.3, 6.4, and 6.5.
1738 * The "load" command now supports writing to flash memory, if the remote
1739 stub provides the required support.
1741 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1742 longer requires symbolic debug information (e.g. DWARF-2).
1747 unset substitute-path
1748 show substitute-path
1749 Manage a list of substitution rules that GDB uses to rewrite the name
1750 of the directories where the sources are located. This can be useful
1751 for instance when the sources were moved to a different location
1752 between compilation and debugging.
1756 Print each CLI command as it is executed. Each command is prefixed with
1757 a number of `+' symbols representing the nesting depth.
1758 The source command now has a `-v' option to enable the same feature.
1762 The ARM Demon monitor support (RDP protocol, "target rdp").
1764 Kernel Object Display, an embedded debugging feature which only worked with
1765 an obsolete version of Cisco IOS.
1767 The 'set download-write-size' and 'show download-write-size' commands.
1769 * New remote packets
1772 Tell a stub about GDB client features, and request remote target features.
1773 The first feature implemented is PacketSize, which allows the target to
1774 specify the size of packets it can handle - to minimize the number of
1775 packets required and improve performance when connected to a remote
1779 Fetch an OS auxilliary vector from the remote stub. This packet is a
1780 more efficient replacement for qPart:auxv:read.
1782 qXfer:memory-map:read:
1783 Fetch a memory map from the remote stub, including information about
1784 RAM, ROM, and flash memory devices.
1789 Erase and program a flash memory device.
1791 * Removed remote packets
1794 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1795 used it, and only gdbserver implemented it.
1797 *** Changes in GDB 6.5
1801 Renesas M32C/M16C m32c-elf
1803 Morpho Technologies ms1 ms1-elf
1807 init-if-undefined Initialize a convenience variable, but
1808 only if it doesn't already have a value.
1810 The following commands are presently only implemented for native GNU/Linux:
1812 checkpoint Save a snapshot of the program state.
1814 restart <n> Return the program state to a
1815 previously saved state.
1817 info checkpoints List currently saved checkpoints.
1819 delete-checkpoint <n> Delete a previously saved checkpoint.
1821 set|show detach-on-fork Tell gdb whether to detach from a newly
1822 forked process, or to keep debugging it.
1824 info forks List forks of the user program that
1825 are available to be debugged.
1827 fork <n> Switch to debugging one of several
1828 forks of the user program that are
1829 available to be debugged.
1831 delete-fork <n> Delete a fork from the list of forks
1832 that are available to be debugged (and
1833 kill the forked process).
1835 detach-fork <n> Delete a fork from the list of forks
1836 that are available to be debugged (and
1837 allow the process to continue).
1841 Morpho Technologies ms2 ms1-elf
1843 * Improved Windows host support
1845 GDB now builds as a cross debugger hosted on i686-mingw32, including
1846 native console support, and remote communications using either
1847 network sockets or serial ports.
1849 * Improved Modula-2 language support
1851 GDB can now print most types in the Modula-2 syntax. This includes:
1852 basic types, set types, record types, enumerated types, range types,
1853 pointer types and ARRAY types. Procedure var parameters are correctly
1854 printed and hexadecimal addresses and character constants are also
1855 written in the Modula-2 syntax. Best results can be obtained by using
1856 GNU Modula-2 together with the -gdwarf-2 command line option.
1860 The ARM rdi-share module.
1862 The Netware NLM debug server.
1864 *** Changes in GDB 6.4
1866 * New native configurations
1868 OpenBSD/arm arm*-*-openbsd*
1869 OpenBSD/mips64 mips64-*-openbsd*
1873 Morpho Technologies ms1 ms1-elf
1875 * New command line options
1877 --batch-silent As for --batch, but totally silent.
1878 --return-child-result The debugger will exist with the same value
1879 the child (debugged) program exited with.
1880 --eval-command COMMAND, -ex COMMAND
1881 Execute a single GDB CLI command. This may be
1882 specified multiple times and in conjunction
1883 with the --command (-x) option.
1885 * Deprecated commands removed
1887 The following commands, that were deprecated in 2000, have been
1891 set|show arm disassembly-flavor set|show arm disassembler
1892 othernames set arm disassembler
1893 set|show remotedebug set|show debug remote
1894 set|show archdebug set|show debug arch
1895 set|show eventdebug set|show debug event
1898 * New BSD user-level threads support
1900 It is now possible to debug programs using the user-level threads
1901 library on OpenBSD and FreeBSD. Currently supported (target)
1904 FreeBSD/amd64 x86_64-*-freebsd*
1905 FreeBSD/i386 i386-*-freebsd*
1906 OpenBSD/i386 i386-*-openbsd*
1908 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1909 are not yet supported.
1911 * New support for Matsushita MN10300 w/sim added
1912 (Work in progress). mn10300-elf.
1914 * REMOVED configurations and files
1916 VxWorks and the XDR protocol *-*-vxworks
1917 Motorola MCORE mcore-*-*
1918 National Semiconductor NS32000 ns32k-*-*
1920 * New "set print array-indexes" command
1922 After turning this setting "on", GDB prints the index of each element
1923 when displaying arrays. The default is "off" to preserve the previous
1926 * VAX floating point support
1928 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1930 * User-defined command support
1932 In addition to using $arg0..$arg9 for argument passing, it is now possible
1933 to use $argc to determine now many arguments have been passed. See the
1934 section on user-defined commands in the user manual for more information.
1936 *** Changes in GDB 6.3:
1938 * New command line option
1940 GDB now accepts -l followed by a number to set the timeout for remote
1943 * GDB works with GCC -feliminate-dwarf2-dups
1945 GDB now supports a more compact representation of DWARF-2 debug
1946 information using DW_FORM_ref_addr references. These are produced
1947 by GCC with the option -feliminate-dwarf2-dups and also by some
1948 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1949 to use -feliminate-dwarf2-dups.
1951 * Internationalization
1953 When supported by the host system, GDB will be built with
1954 internationalization (libintl). The task of marking up the sources is
1955 continued, we're looking forward to our first translation.
1959 Initial support for debugging programs compiled with the GNAT
1960 implementation of the Ada programming language has been integrated
1961 into GDB. In this release, support is limited to expression evaluation.
1963 * New native configurations
1965 GNU/Linux/m32r m32r-*-linux-gnu
1969 GDB's remote protocol now includes support for the 'p' packet. This
1970 packet is used to fetch individual registers from a remote inferior.
1972 * END-OF-LIFE registers[] compatibility module
1974 GDB's internal register infrastructure has been completely rewritten.
1975 The new infrastructure making possible the implementation of key new
1976 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1979 GDB 6.3 will be the last release to include the the registers[]
1980 compatibility module that allowed out-of-date configurations to
1981 continue to work. This change directly impacts the following
1991 powerpc bdm protocol
1993 Unless there is activity to revive these configurations, they will be
1994 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1996 * OBSOLETE configurations and files
1998 Configurations that have been declared obsolete in this release have
1999 been commented out. Unless there is activity to revive these
2000 configurations, the next release of GDB will have their sources
2001 permanently REMOVED.
2010 *** Changes in GDB 6.2.1:
2012 * MIPS `break main; run' gave an heuristic-fence-post warning
2014 When attempting to run even a simple program, a warning about
2015 heuristic-fence-post being hit would be reported. This problem has
2018 * MIPS IRIX 'long double' crashed GDB
2020 When examining a long double variable, GDB would get a segmentation
2021 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2022 IRIX long double values).
2026 A bug in the VAX stack code was causing problems with the "next"
2027 command. This problem has been fixed.
2029 *** Changes in GDB 6.2:
2031 * Fix for ``many threads''
2033 On GNU/Linux systems that use the NPTL threads library, a program
2034 rapidly creating and deleting threads would confuse GDB leading to the
2037 ptrace: No such process.
2038 thread_db_get_info: cannot get thread info: generic error
2040 This problem has been fixed.
2042 * "-async" and "-noasync" options removed.
2044 Support for the broken "-noasync" option has been removed (it caused
2047 * New ``start'' command.
2049 This command runs the program until the begining of the main procedure.
2051 * New BSD Kernel Data Access Library (libkvm) interface
2053 Using ``target kvm'' it is now possible to debug kernel core dumps and
2054 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2055 platforms. Currently supported (native-only) configurations are:
2057 FreeBSD/amd64 x86_64-*-freebsd*
2058 FreeBSD/i386 i?86-*-freebsd*
2059 NetBSD/i386 i?86-*-netbsd*
2060 NetBSD/m68k m68*-*-netbsd*
2061 NetBSD/sparc sparc-*-netbsd*
2062 OpenBSD/amd64 x86_64-*-openbsd*
2063 OpenBSD/i386 i?86-*-openbsd*
2064 OpenBSD/m68k m68*-openbsd*
2065 OpenBSD/sparc sparc-*-openbsd*
2067 * Signal trampoline code overhauled
2069 Many generic problems with GDB's signal handling code have been fixed.
2070 These include: backtraces through non-contiguous stacks; recognition
2071 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2072 call; backtrace through a signal trampoline; step into and out of
2073 signal handlers; and single-stepping in the signal trampoline.
2075 Please note that kernel bugs are a limiting factor here. These
2076 features have been shown to work on an s390 GNU/Linux system that
2077 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2079 * Cygwin support for DWARF 2 added.
2081 * New native configurations
2083 GNU/Linux/hppa hppa*-*-linux*
2084 OpenBSD/hppa hppa*-*-openbsd*
2085 OpenBSD/m68k m68*-*-openbsd*
2086 OpenBSD/m88k m88*-*-openbsd*
2087 OpenBSD/powerpc powerpc-*-openbsd*
2088 NetBSD/vax vax-*-netbsd*
2089 OpenBSD/vax vax-*-openbsd*
2091 * END-OF-LIFE frame compatibility module
2093 GDB's internal frame infrastructure has been completely rewritten.
2094 The new infrastructure making it possible to support key new features
2095 including DWARF 2 Call Frame Information. To aid in the task of
2096 migrating old configurations to this new infrastructure, a
2097 compatibility module, that allowed old configurations to continue to
2098 work, was also included.
2100 GDB 6.2 will be the last release to include this frame compatibility
2101 module. This change directly impacts the following configurations:
2111 Unless there is activity to revive these configurations, they will be
2112 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2114 * REMOVED configurations and files
2116 Sun 3, running SunOS 3 m68*-*-sunos3*
2117 Sun 3, running SunOS 4 m68*-*-sunos4*
2118 Sun 2, running SunOS 3 m68000-*-sunos3*
2119 Sun 2, running SunOS 4 m68000-*-sunos4*
2120 Motorola 680x0 running LynxOS m68*-*-lynxos*
2121 AT&T 3b1/Unix pc m68*-att-*
2122 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2123 decstation mips-dec-* mips-little-*
2124 riscos mips-*-riscos* mips-*-sysv*
2125 sonymips mips-sony-*
2126 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2128 *** Changes in GDB 6.1.1:
2130 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2132 The TUI (Text-mode User Interface) is now built as part of a default
2133 GDB configuration. It is enabled by either selecting the TUI with the
2134 command line option "-i=tui" or by running the separate "gdbtui"
2135 program. For more information on the TUI, see the manual "Debugging
2138 * Pending breakpoint support (also included in GDB 6.1)
2140 Support has been added to allow you to specify breakpoints in shared
2141 libraries that have not yet been loaded. If a breakpoint location
2142 cannot be found, and the "breakpoint pending" option is set to auto,
2143 GDB queries you if you wish to make the breakpoint pending on a future
2144 shared-library load. If and when GDB resolves the breakpoint symbol,
2145 the pending breakpoint is removed as one or more regular breakpoints
2148 Pending breakpoints are very useful for GCJ Java debugging.
2150 * Fixed ISO-C build problems
2152 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2153 non ISO-C code that stopped them being built using a more strict ISO-C
2154 compiler (e.g., IBM's C compiler).
2156 * Fixed build problem on IRIX 5
2158 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2159 wasn't able to compile compile on an IRIX 5 system.
2161 * Added execute permission to gdb/gdbserver/configure
2163 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2164 permission. This bug would cause configure to fail on a number of
2165 systems (Solaris, IRIX). Ref: server/519.
2167 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2169 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2170 has been updated to use constant array sizes.
2172 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2174 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2175 its generated DWARF Call Frame Info. This encoding was causing GDB to
2176 panic, that panic has been fixed. Ref: gdb/1628.
2178 * Fixed a problem when examining parameters in shared library code.
2180 When examining parameters in optimized shared library code generated
2181 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2182 not available''. GDB now correctly displays the variable's value.
2184 *** Changes in GDB 6.1:
2186 * Removed --with-mmalloc
2188 Support for the mmalloc memory manager has been removed, as it
2189 conflicted with the internal gdb byte cache.
2191 * Changes in AMD64 configurations
2193 The AMD64 target now includes the %cs and %ss registers. As a result
2194 the AMD64 remote protocol has changed; this affects the floating-point
2195 and SSE registers. If you rely on those registers for your debugging,
2196 you should upgrade gdbserver on the remote side.
2198 * Revised SPARC target
2200 The SPARC target has been completely revised, incorporating the
2201 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2202 support for LynxOS and SunOS 4 has been dropped. Calling functions
2203 from within GDB on operating systems with a non-executable stack
2204 (Solaris, OpenBSD) now works.
2208 GDB has a new C++ demangler which does a better job on the mangled
2209 names generated by current versions of g++. It also runs faster, so
2210 with this and other changes gdb should now start faster on large C++
2213 * DWARF 2 Location Expressions
2215 GDB support for location expressions has been extended to support function
2216 arguments and frame bases. Older versions of GDB could crash when they
2219 * C++ nested types and namespaces
2221 GDB's support for nested types and namespaces in C++ has been
2222 improved, especially if you use the DWARF 2 debugging format. (This
2223 is the default for recent versions of GCC on most platforms.)
2224 Specifically, if you have a class "Inner" defined within a class or
2225 namespace "Outer", then GDB realizes that the class's name is
2226 "Outer::Inner", not simply "Inner". This should greatly reduce the
2227 frequency of complaints about not finding RTTI symbols. In addition,
2228 if you are stopped at inside of a function defined within a namespace,
2229 GDB modifies its name lookup accordingly.
2231 * New native configurations
2233 NetBSD/amd64 x86_64-*-netbsd*
2234 OpenBSD/amd64 x86_64-*-openbsd*
2235 OpenBSD/alpha alpha*-*-openbsd*
2236 OpenBSD/sparc sparc-*-openbsd*
2237 OpenBSD/sparc64 sparc64-*-openbsd*
2239 * New debugging protocols
2241 M32R with SDI protocol m32r-*-elf*
2243 * "set prompt-escape-char" command deleted.
2245 The command "set prompt-escape-char" has been deleted. This command,
2246 and its very obscure effet on GDB's prompt, was never documented,
2247 tested, nor mentioned in the NEWS file.
2249 * OBSOLETE configurations and files
2251 Configurations that have been declared obsolete in this release have
2252 been commented out. Unless there is activity to revive these
2253 configurations, the next release of GDB will have their sources
2254 permanently REMOVED.
2256 Sun 3, running SunOS 3 m68*-*-sunos3*
2257 Sun 3, running SunOS 4 m68*-*-sunos4*
2258 Sun 2, running SunOS 3 m68000-*-sunos3*
2259 Sun 2, running SunOS 4 m68000-*-sunos4*
2260 Motorola 680x0 running LynxOS m68*-*-lynxos*
2261 AT&T 3b1/Unix pc m68*-att-*
2262 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2263 decstation mips-dec-* mips-little-*
2264 riscos mips-*-riscos* mips-*-sysv*
2265 sonymips mips-sony-*
2266 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2268 * REMOVED configurations and files
2270 SGI Irix-4.x mips-sgi-irix4 or iris4
2271 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2272 Z8000 simulator z8k-zilog-none or z8ksim
2273 Matsushita MN10200 w/simulator mn10200-*-*
2274 H8/500 simulator h8500-hitachi-hms or h8500hms
2275 HP/PA running BSD hppa*-*-bsd*
2276 HP/PA running OSF/1 hppa*-*-osf*
2277 HP/PA Pro target hppa*-*-pro*
2278 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2279 386BSD i[3456]86-*-bsd*
2280 Sequent family i[3456]86-sequent-sysv4*
2281 i[3456]86-sequent-sysv*
2282 i[3456]86-sequent-bsd*
2283 SPARC running LynxOS sparc-*-lynxos*
2284 SPARC running SunOS 4 sparc-*-sunos4*
2285 Tsqware Sparclet sparclet-*-*
2286 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2288 *** Changes in GDB 6.0:
2292 Support for debugging the Objective-C programming language has been
2293 integrated into GDB.
2295 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2297 DWARF 2's Call Frame Information makes available compiler generated
2298 information that more exactly describes the program's run-time stack.
2299 By using this information, GDB is able to provide more robust stack
2302 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2303 have been updated to use a new backtrace mechanism which includes
2304 DWARF 2 CFI support.
2308 GDB's remote protocol has been extended to include support for hosted
2309 file I/O (where the remote target uses GDB's file system). See GDB's
2310 remote protocol documentation for details.
2312 * All targets using the new architecture framework.
2314 All of GDB's targets have been updated to use the new internal
2315 architecture framework. The way is now open for future GDB releases
2316 to include cross-architecture native debugging support (i386 on amd64,
2319 * GNU/Linux's Thread Local Storage (TLS)
2321 GDB now includes support for for the GNU/Linux implementation of
2322 per-thread variables.
2324 * GNU/Linux's Native POSIX Thread Library (NPTL)
2326 GDB's thread code has been updated to work with either the new
2327 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2329 * Separate debug info.
2331 GDB, in conjunction with BINUTILS, now supports a mechanism for
2332 automatically loading debug information from a separate file. Instead
2333 of shipping full debug and non-debug versions of system libraries,
2334 system integrators can now instead ship just the stripped libraries
2335 and optional debug files.
2337 * DWARF 2 Location Expressions
2339 DWARF 2 Location Expressions allow the compiler to more completely
2340 describe the location of variables (even in optimized code) to the
2343 GDB now includes preliminary support for location expressions (support
2344 for DW_OP_piece is still missing).
2348 A number of long standing bugs that caused GDB to die while starting a
2349 Java application have been fixed. GDB's Java support is now
2350 considered "useable".
2352 * GNU/Linux support for fork, vfork, and exec.
2354 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2355 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2358 * GDB supports logging output to a file
2360 There are two new commands, "set logging" and "show logging", which can be
2361 used to capture GDB's output to a file.
2363 * The meaning of "detach" has changed for gdbserver
2365 The "detach" command will now resume the application, as documented. To
2366 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2369 * d10v, m68hc11 `regs' command deprecated
2371 The `info registers' command has been updated so that it displays the
2372 registers using a format identical to the old `regs' command.
2376 A new command, "maint set profile on/off", has been added. This command can
2377 be used to enable or disable profiling while running GDB, to profile a
2378 session or a set of commands. In addition there is a new configure switch,
2379 "--enable-profiling", which will cause GDB to be compiled with profiling
2380 data, for more informative profiling results.
2382 * Default MI syntax changed to "mi2".
2384 The default MI (machine interface) syntax, enabled by the command line
2385 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2386 "mi1", can be enabled by specifying the option "-i=mi1".
2388 Support for the original "mi0" syntax (included in GDB 5.0) has been
2391 Fix for gdb/192: removed extraneous space when displaying frame level.
2392 Fix for gdb/672: update changelist is now output in mi list format.
2393 Fix for gdb/702: a -var-assign that updates the value now shows up
2394 in a subsequent -var-update.
2396 * New native configurations.
2398 FreeBSD/amd64 x86_64-*-freebsd*
2400 * Multi-arched targets.
2402 HP/PA HPUX11 hppa*-*-hpux*
2403 Renesas M32R/D w/simulator m32r-*-elf*
2405 * OBSOLETE configurations and files
2407 Configurations that have been declared obsolete in this release have
2408 been commented out. Unless there is activity to revive these
2409 configurations, the next release of GDB will have their sources
2410 permanently REMOVED.
2412 Z8000 simulator z8k-zilog-none or z8ksim
2413 Matsushita MN10200 w/simulator mn10200-*-*
2414 H8/500 simulator h8500-hitachi-hms or h8500hms
2415 HP/PA running BSD hppa*-*-bsd*
2416 HP/PA running OSF/1 hppa*-*-osf*
2417 HP/PA Pro target hppa*-*-pro*
2418 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2419 Sequent family i[3456]86-sequent-sysv4*
2420 i[3456]86-sequent-sysv*
2421 i[3456]86-sequent-bsd*
2422 Tsqware Sparclet sparclet-*-*
2423 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2425 * REMOVED configurations and files
2428 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2429 IBM AIX PS/2 i[3456]86-*-aix
2430 i386 running Mach 3.0 i[3456]86-*-mach3*
2431 i386 running Mach i[3456]86-*-mach*
2432 i386 running OSF/1 i[3456]86-*osf1mk*
2433 HP/Apollo 68k Family m68*-apollo*-sysv*,
2435 m68*-hp-bsd*, m68*-hp-hpux*
2436 Argonaut Risc Chip (ARC) arc-*-*
2437 Mitsubishi D30V d30v-*-*
2438 Fujitsu FR30 fr30-*-elf*
2439 OS/9000 i[34]86-*-os9k
2440 I960 with MON960 i960-*-coff
2442 * MIPS $fp behavior changed
2444 The convenience variable $fp, for the MIPS, now consistently returns
2445 the address of the current frame's base. Previously, depending on the
2446 context, $fp could refer to either $sp or the current frame's base
2447 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2448 The GNU Source-Level Debugger''.
2450 *** Changes in GDB 5.3:
2452 * GNU/Linux shared library multi-threaded performance improved.
2454 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2455 `/proc', in preference to `ptrace' for memory reads. This may result
2456 in an improvement in the start-up time of multi-threaded, shared
2457 library applications when run under GDB. One GDB user writes: ``loads
2458 shared libs like mad''.
2460 * ``gdbserver'' now supports multi-threaded applications on some targets
2462 Support for debugging multi-threaded applications which use
2463 the GNU/Linux LinuxThreads package has been added for
2464 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2465 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2467 * GDB now supports C/C++ preprocessor macros.
2469 GDB now expands preprocessor macro invocations in C/C++ expressions,
2470 and provides various commands for showing macro definitions and how
2473 The new command `macro expand EXPRESSION' expands any macro
2474 invocations in expression, and shows the result.
2476 The new command `show macro MACRO-NAME' shows the definition of the
2477 macro named MACRO-NAME, and where it was defined.
2479 Most compilers don't include information about macros in the debugging
2480 information by default. In GCC 3.1, for example, you need to compile
2481 your program with the options `-gdwarf-2 -g3'. If the macro
2482 information is present in the executable, GDB will read it.
2484 * Multi-arched targets.
2486 DEC Alpha (partial) alpha*-*-*
2487 DEC VAX (partial) vax-*-*
2489 National Semiconductor NS32000 (partial) ns32k-*-*
2490 Motorola 68000 (partial) m68k-*-*
2491 Motorola MCORE mcore-*-*
2495 Fujitsu FRV architecture added by Red Hat frv*-*-*
2498 * New native configurations
2500 Alpha NetBSD alpha*-*-netbsd*
2501 SH NetBSD sh*-*-netbsdelf*
2502 MIPS NetBSD mips*-*-netbsd*
2503 UltraSPARC NetBSD sparc64-*-netbsd*
2505 * OBSOLETE configurations and files
2507 Configurations that have been declared obsolete in this release have
2508 been commented out. Unless there is activity to revive these
2509 configurations, the next release of GDB will have their sources
2510 permanently REMOVED.
2512 Mitsubishi D30V d30v-*-*
2513 OS/9000 i[34]86-*-os9k
2514 IBM AIX PS/2 i[3456]86-*-aix
2515 Fujitsu FR30 fr30-*-elf*
2516 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2517 Argonaut Risc Chip (ARC) arc-*-*
2518 i386 running Mach 3.0 i[3456]86-*-mach3*
2519 i386 running Mach i[3456]86-*-mach*
2520 i386 running OSF/1 i[3456]86-*osf1mk*
2521 HP/Apollo 68k Family m68*-apollo*-sysv*,
2523 m68*-hp-bsd*, m68*-hp-hpux*
2524 I960 with MON960 i960-*-coff
2526 * OBSOLETE languages
2528 CHILL, a Pascal like language used by telecommunications companies.
2530 * REMOVED configurations and files
2532 AMD 29k family via UDI a29k-amd-udi, udi29k
2533 A29K VxWorks a29k-*-vxworks
2534 AMD 29000 embedded, using EBMON a29k-none-none
2535 AMD 29000 embedded with COFF a29k-none-coff
2536 AMD 29000 embedded with a.out a29k-none-aout
2538 testsuite/gdb.hp/gdb.threads-hp/ directory
2540 * New command "set max-user-call-depth <nnn>"
2542 This command allows the user to limit the call depth of user-defined
2543 commands. The default is 1024.
2545 * Changes in FreeBSD/i386 native debugging.
2547 Support for the "generate-core-file" has been added.
2549 * New commands "dump", "append", and "restore".
2551 These commands allow data to be copied from target memory
2552 to a bfd-format or binary file (dump and append), and back
2553 from a file into memory (restore).
2555 * Improved "next/step" support on multi-processor Alpha Tru64.
2557 The previous single-step mechanism could cause unpredictable problems,
2558 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2559 of a software single-step mechanism prevents this.
2561 *** Changes in GDB 5.2.1:
2569 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2570 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2571 Fix, by Joel Brobecker imported from mainline.
2573 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2574 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2575 Fix, by Fred Fish, imported from mainline.
2577 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2578 Surprisingly enough, it works now.
2579 By Michal Ludvig, imported from mainline.
2581 i386 hardware watchpoint support:
2582 avoid misses on second run for some targets.
2583 By Pierre Muller, imported from mainline.
2585 *** Changes in GDB 5.2:
2587 * New command "set trust-readonly-sections on[off]".
2589 This command is a hint that tells gdb that read-only sections
2590 really are read-only (ie. that their contents will not change).
2591 In this mode, gdb will go to the object file rather than the
2592 target to read memory from read-only sections (such as ".text").
2593 This can be a significant performance improvement on some
2594 (notably embedded) targets.
2596 * New command "generate-core-file" (or "gcore").
2598 This new gdb command allows the user to drop a core file of the child
2599 process state at any time. So far it's been implemented only for
2600 GNU/Linux and Solaris, but should be relatively easily ported to other
2601 hosts. Argument is core file name (defaults to core.<pid>).
2603 * New command line option
2605 GDB now accepts --pid or -p followed by a process id.
2607 * Change in command line behavior -- corefiles vs. process ids.
2609 There is a subtle behavior in the way in which GDB handles
2610 command line arguments. The first non-flag argument is always
2611 a program to debug, but the second non-flag argument may either
2612 be a corefile or a process id. Previously, GDB would attempt to
2613 open the second argument as a corefile, and if that failed, would
2614 issue a superfluous error message and then attempt to attach it as
2615 a process. Now, if the second argument begins with a non-digit,
2616 it will be treated as a corefile. If it begins with a digit,
2617 GDB will attempt to attach it as a process, and if no such process
2618 is found, will then attempt to open it as a corefile.
2620 * Changes in ARM configurations.
2622 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2623 configuration is fully multi-arch.
2625 * New native configurations
2627 ARM NetBSD arm*-*-netbsd*
2628 x86 OpenBSD i[3456]86-*-openbsd*
2629 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2630 Sparc64 running FreeBSD sparc64-*-freebsd*
2634 Sanyo XStormy16 xstormy16-elf
2636 * OBSOLETE configurations and files
2638 Configurations that have been declared obsolete in this release have
2639 been commented out. Unless there is activity to revive these
2640 configurations, the next release of GDB will have their sources
2641 permanently REMOVED.
2643 AMD 29k family via UDI a29k-amd-udi, udi29k
2644 A29K VxWorks a29k-*-vxworks
2645 AMD 29000 embedded, using EBMON a29k-none-none
2646 AMD 29000 embedded with COFF a29k-none-coff
2647 AMD 29000 embedded with a.out a29k-none-aout
2649 testsuite/gdb.hp/gdb.threads-hp/ directory
2651 * REMOVED configurations and files
2653 TI TMS320C80 tic80-*-*
2655 PowerPC Solaris powerpcle-*-solaris*
2656 PowerPC Windows NT powerpcle-*-cygwin32
2657 PowerPC Netware powerpc-*-netware*
2658 Harris/CXUX m88k m88*-harris-cxux*
2659 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2660 ns32k-utek-sysv* ns32k-utek-*
2661 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2662 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2663 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2664 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2665 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2667 * Changes to command line processing
2669 The new `--args' feature can be used to specify command-line arguments
2670 for the inferior from gdb's command line.
2672 * Changes to key bindings
2674 There is a new `operate-and-get-next' function bound to `C-o'.
2676 *** Changes in GDB 5.1.1
2678 Fix compile problem on DJGPP.
2680 Fix a problem with floating-point registers on the i386 being
2683 Fix to stop GDB crashing on .debug_str debug info.
2685 Numerous documentation fixes.
2687 Numerous testsuite fixes.
2689 *** Changes in GDB 5.1:
2691 * New native configurations
2693 Alpha FreeBSD alpha*-*-freebsd*
2694 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2695 MIPS GNU/Linux mips*-*-linux*
2696 MIPS SGI Irix 6.x mips*-sgi-irix6*
2697 ia64 AIX ia64-*-aix*
2698 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2702 Motorola 68HC11 and 68HC12 m68hc11-elf
2704 UltraSparc running GNU/Linux sparc64-*-linux*
2706 * OBSOLETE configurations and files
2708 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2709 Harris/CXUX m88k m88*-harris-cxux*
2710 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2711 ns32k-utek-sysv* ns32k-utek-*
2712 TI TMS320C80 tic80-*-*
2714 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2715 PowerPC Solaris powerpcle-*-solaris*
2716 PowerPC Windows NT powerpcle-*-cygwin32
2717 PowerPC Netware powerpc-*-netware*
2718 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2719 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2720 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2721 Apple Macintosh (MPW) host N/A
2723 stuff.c (Program to stuff files into a specially prepared space in kdb)
2724 kdb-start.c (Main loop for the standalone kernel debugger)
2726 Configurations that have been declared obsolete in this release have
2727 been commented out. Unless there is activity to revive these
2728 configurations, the next release of GDB will have their sources
2729 permanently REMOVED.
2731 * REMOVED configurations and files
2733 Altos 3068 m68*-altos-*
2734 Convex c1-*-*, c2-*-*
2736 ARM RISCix arm-*-* (as host)
2740 * GDB has been converted to ISO C.
2742 GDB's source code has been converted to ISO C. In particular, the
2743 sources are fully protoized, and rely on standard headers being
2748 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2750 * The MI enabled by default.
2752 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2753 revised and enabled by default. Packages which use GDB as a debugging
2754 engine behind a UI or another front end are encouraged to switch to
2755 using the GDB/MI interface, instead of the old annotations interface
2756 which is now deprecated.
2758 * Support for debugging Pascal programs.
2760 GDB now includes support for debugging Pascal programs. The following
2761 main features are supported:
2763 - Pascal-specific data types such as sets;
2765 - automatic recognition of Pascal sources based on file-name
2768 - Pascal-style display of data types, variables, and functions;
2770 - a Pascal expression parser.
2772 However, some important features are not yet supported.
2774 - Pascal string operations are not supported at all;
2776 - there are some problems with boolean types;
2778 - Pascal type hexadecimal constants are not supported
2779 because they conflict with the internal variables format;
2781 - support for Pascal objects and classes is not full yet;
2783 - unlike Pascal, GDB is case-sensitive for symbol names.
2785 * Changes in completion.
2787 Commands such as `shell', `run' and `set args', which pass arguments
2788 to inferior programs, now complete on file names, similar to what
2789 users expect at the shell prompt.
2791 Commands which accept locations, such as `disassemble', `print',
2792 `breakpoint', `until', etc. now complete on filenames as well as
2793 program symbols. Thus, if you type "break foob TAB", and the source
2794 files linked into the programs include `foobar.c', that file name will
2795 be one of the candidates for completion. However, file names are not
2796 considered for completion after you typed a colon that delimits a file
2797 name from a name of a function in that file, as in "break foo.c:bar".
2799 `set demangle-style' completes on available demangling styles.
2801 * New platform-independent commands:
2803 It is now possible to define a post-hook for a command as well as a
2804 hook that runs before the command. For more details, see the
2805 documentation of `hookpost' in the GDB manual.
2807 * Changes in GNU/Linux native debugging.
2809 Support for debugging multi-threaded programs has been completely
2810 revised for all platforms except m68k and sparc. You can now debug as
2811 many threads as your system allows you to have.
2813 Attach/detach is supported for multi-threaded programs.
2815 Support for SSE registers was added for x86. This doesn't work for
2816 multi-threaded programs though.
2818 * Changes in MIPS configurations.
2820 Multi-arch support is enabled for all MIPS configurations.
2822 GDB can now be built as native debugger on SGI Irix 6.x systems for
2823 debugging n32 executables. (Debugging 64-bit executables is not yet
2826 * Unified support for hardware watchpoints in all x86 configurations.
2828 Most (if not all) native x86 configurations support hardware-assisted
2829 breakpoints and watchpoints in a unified manner. This support
2830 implements debug register sharing between watchpoints, which allows to
2831 put a virtually infinite number of watchpoints on the same address,
2832 and also supports watching regions up to 16 bytes with several debug
2835 The new maintenance command `maintenance show-debug-regs' toggles
2836 debugging print-outs in functions that insert, remove, and test
2837 watchpoints and hardware breakpoints.
2839 * Changes in the DJGPP native configuration.
2841 New command ``info dos sysinfo'' displays assorted information about
2842 the CPU, OS, memory, and DPMI server.
2844 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2845 display information about segment descriptors stored in GDT, LDT, and
2848 New commands ``info dos pde'' and ``info dos pte'' display entries
2849 from Page Directory and Page Tables (for now works with CWSDPMI only).
2850 New command ``info dos address-pte'' displays the Page Table entry for
2851 a given linear address.
2853 GDB can now pass command lines longer than 126 characters to the
2854 program being debugged (requires an update to the libdbg.a library
2855 which is part of the DJGPP development kit).
2857 DWARF2 debug info is now supported.
2859 It is now possible to `step' and `next' through calls to `longjmp'.
2861 * Changes in documentation.
2863 All GDB documentation was converted to GFDL, the GNU Free
2864 Documentation License.
2866 Tracepoints-related commands are now fully documented in the GDB
2869 TUI, the Text-mode User Interface, is now documented in the manual.
2871 Tracepoints-related commands are now fully documented in the GDB
2874 The "GDB Internals" manual now has an index. It also includes
2875 documentation of `ui_out' functions, GDB coding standards, x86
2876 hardware watchpoints, and memory region attributes.
2878 * GDB's version number moved to ``version.in''
2880 The Makefile variable VERSION has been replaced by the file
2881 ``version.in''. People creating GDB distributions should update the
2882 contents of this file.
2886 GUD support is now a standard part of the EMACS distribution.
2888 *** Changes in GDB 5.0:
2890 * Improved support for debugging FP programs on x86 targets
2892 Unified and much-improved support for debugging floating-point
2893 programs on all x86 targets. In particular, ``info float'' now
2894 displays the FP registers in the same format on all x86 targets, with
2895 greater level of detail.
2897 * Improvements and bugfixes in hardware-assisted watchpoints
2899 It is now possible to watch array elements, struct members, and
2900 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2901 on x86 targets no longer erroneously trigger when the address is
2904 * Improvements in the native DJGPP version of GDB
2906 The distribution now includes all the scripts and auxiliary files
2907 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2908 machines ``out of the box''.
2910 The DJGPP version can now debug programs that use signals. It is
2911 possible to catch signals that happened in the debuggee, deliver
2912 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2913 would kill the program being debugged.) Programs that hook hardware
2914 interrupts (keyboard, timer, etc.) can also be debugged.
2916 It is now possible to debug DJGPP programs that redirect their
2917 standard handles or switch them to raw (as opposed to cooked) mode, or
2918 even close them. The command ``run < foo > bar'' works as expected,
2919 and ``info terminal'' reports useful information about the debuggee's
2920 terminal, including raw/cooked mode, redirection, etc.
2922 The DJGPP version now uses termios functions for console I/O, which
2923 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2926 DOS-style file names with drive letters are now fully supported by
2929 It is now possible to debug DJGPP programs that switch their working
2930 directory. It is also possible to rerun the debuggee any number of
2931 times without restarting GDB; thus, you can use the same setup,
2932 breakpoints, etc. for many debugging sessions.
2934 * New native configurations
2936 ARM GNU/Linux arm*-*-linux*
2937 PowerPC GNU/Linux powerpc-*-linux*
2941 Motorola MCore mcore-*-*
2942 x86 VxWorks i[3456]86-*-vxworks*
2943 PowerPC VxWorks powerpc-*-vxworks*
2944 TI TMS320C80 tic80-*-*
2946 * OBSOLETE configurations
2948 Altos 3068 m68*-altos-*
2949 Convex c1-*-*, c2-*-*
2951 ARM RISCix arm-*-* (as host)
2954 Configurations that have been declared obsolete will be commented out,
2955 but the code will be left in place. If there is no activity to revive
2956 these configurations before the next release of GDB, the sources will
2957 be permanently REMOVED.
2959 * Gould support removed
2961 Support for the Gould PowerNode and NP1 has been removed.
2963 * New features for SVR4
2965 On SVR4 native platforms (such as Solaris), if you attach to a process
2966 without first loading a symbol file, GDB will now attempt to locate and
2967 load symbols from the running process's executable file.
2969 * Many C++ enhancements
2971 C++ support has been greatly improved. Overload resolution now works properly
2972 in almost all cases. RTTI support is on the way.
2974 * Remote targets can connect to a sub-program
2976 A popen(3) style serial-device has been added. This device starts a
2977 sub-process (such as a stand-alone simulator) and then communicates
2978 with that. The sub-program to run is specified using the syntax
2979 ``|<program> <args>'' vis:
2981 (gdb) set remotedebug 1
2982 (gdb) target extended-remote |mn10300-elf-sim program-args
2984 * MIPS 64 remote protocol
2986 A long standing bug in the mips64 remote protocol where by GDB
2987 expected certain 32 bit registers (ex SR) to be transfered as 32
2988 instead of 64 bits has been fixed.
2990 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2991 added to provide backward compatibility with older versions of GDB.
2993 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2995 The command ``set remotebinarydownload'' command has been replaced by
2996 ``set remote X-packet''. Other commands in ``set remote'' family
2997 include ``set remote P-packet''.
2999 * Breakpoint commands accept ranges.
3001 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3002 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3003 ``tracepoint passcount'' also accepts a range of tracepoints.
3005 * ``apropos'' command added.
3007 The ``apropos'' command searches through command names and
3008 documentation strings, printing out matches, making it much easier to
3009 try to find a command that does what you are looking for.
3013 A new machine oriented interface (MI) has been added to GDB. This
3014 interface is designed for debug environments running GDB as a separate
3015 process. This is part of the long term libGDB project. See the
3016 "GDB/MI" chapter of the GDB manual for further information. It can be
3017 enabled by configuring with:
3019 .../configure --enable-gdbmi
3021 *** Changes in GDB-4.18:
3023 * New native configurations
3025 HP-UX 10.20 hppa*-*-hpux10.20
3026 HP-UX 11.x hppa*-*-hpux11.0*
3027 M68K GNU/Linux m68*-*-linux*
3031 Fujitsu FR30 fr30-*-elf*
3032 Intel StrongARM strongarm-*-*
3033 Mitsubishi D30V d30v-*-*
3035 * OBSOLETE configurations
3037 Gould PowerNode, NP1 np1-*-*, pn-*-*
3039 Configurations that have been declared obsolete will be commented out,
3040 but the code will be left in place. If there is no activity to revive
3041 these configurations before the next release of GDB, the sources will
3042 be permanently REMOVED.
3046 As a compatibility experiment, GDB's source files buildsym.h and
3047 buildsym.c have been converted to pure standard C, no longer
3048 containing any K&R compatibility code. We believe that all systems in
3049 use today either come with a standard C compiler, or have a GCC port
3050 available. If this is not true, please report the affected
3051 configuration to bug-gdb@gnu.org immediately. See the README file for
3052 information about getting a standard C compiler if you don't have one
3057 GDB now uses readline 2.2.
3059 * set extension-language
3061 You can now control the mapping between filename extensions and source
3062 languages by using the `set extension-language' command. For instance,
3063 you can ask GDB to treat .c files as C++ by saying
3064 set extension-language .c c++
3065 The command `info extensions' lists all of the recognized extensions
3066 and their associated languages.
3068 * Setting processor type for PowerPC and RS/6000
3070 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3071 you can use the `set processor' command to specify what variant of the
3072 PowerPC family you are debugging. The command
3076 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3077 following PowerPC and RS6000 variants:
3079 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3080 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3082 403GC IBM PowerPC 403GC
3083 505 Motorola PowerPC 505
3084 860 Motorola PowerPC 860 or 850
3085 601 Motorola PowerPC 601
3086 602 Motorola PowerPC 602
3087 603 Motorola/IBM PowerPC 603 or 603e
3088 604 Motorola PowerPC 604 or 604e
3089 750 Motorola/IBM PowerPC 750 or 750
3091 At the moment, this command just tells GDB what to name the
3092 special-purpose processor registers. Since almost all the affected
3093 registers are inaccessible to user-level programs, this command is
3094 only useful for remote debugging in its present form.
3098 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3099 more extensive support for HP-UX. Added features include shared
3100 library support, kernel threads and hardware watchpoints for 11.00,
3101 support for HP's ANSI C and C++ compilers, and a compatibility mode
3102 for xdb and dbx commands.
3106 HP's donation includes the new concept of catchpoints, which is a
3107 generalization of the old catch command. On HP-UX, it is now possible
3108 to catch exec, fork, and vfork, as well as library loading.
3110 This means that the existing catch command has changed; its first
3111 argument now specifies the type of catch to be set up. See the
3112 output of "help catch" for a list of catchpoint types.
3114 * Debugging across forks
3116 On HP-UX, you can choose which process to debug when a fork() happens
3121 HP has donated a curses-based terminal user interface (TUI). To get
3122 it, build with --enable-tui. Although this can be enabled for any
3123 configuration, at present it only works for native HP debugging.
3125 * GDB remote protocol additions
3127 A new protocol packet 'X' that writes binary data is now available.
3128 Default behavior is to try 'X', then drop back to 'M' if the stub
3129 fails to respond. The settable variable `remotebinarydownload'
3130 allows explicit control over the use of 'X'.
3132 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3133 full 64-bit address. The command
3135 set remoteaddresssize 32
3137 can be used to revert to the old behaviour. For existing remote stubs
3138 the change should not be noticed, as the additional address information
3141 In order to assist in debugging stubs, you may use the maintenance
3142 command `packet' to send any text string to the stub. For instance,
3144 maint packet heythere
3146 sends the packet "$heythere#<checksum>". Note that it is very easy to
3147 disrupt a debugging session by sending the wrong packet at the wrong
3150 The compare-sections command allows you to compare section data on the
3151 target to what is in the executable file without uploading or
3152 downloading, by comparing CRC checksums.
3154 * Tracing can collect general expressions
3156 You may now collect general expressions at tracepoints. This requires
3157 further additions to the target-side stub; see tracepoint.c and
3158 doc/agentexpr.texi for further details.
3160 * mask-address variable for Mips
3162 For Mips targets, you may control the zeroing of the upper 32 bits of
3163 a 64-bit address by entering `set mask-address on'. This is mainly
3164 of interest to users of embedded R4xxx and R5xxx processors.
3166 * Higher serial baud rates
3168 GDB's serial code now allows you to specify baud rates 57600, 115200,
3169 230400, and 460800 baud. (Note that your host system may not be able
3170 to achieve all of these rates.)
3174 The i960 configuration now includes an initial implementation of a
3175 builtin simulator, contributed by Jim Wilson.
3178 *** Changes in GDB-4.17:
3180 * New native configurations
3182 Alpha GNU/Linux alpha*-*-linux*
3183 Unixware 2.x i[3456]86-unixware2*
3184 Irix 6.x mips*-sgi-irix6*
3185 PowerPC GNU/Linux powerpc-*-linux*
3186 PowerPC Solaris powerpcle-*-solaris*
3187 Sparc GNU/Linux sparc-*-linux*
3188 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3192 Argonaut Risc Chip (ARC) arc-*-*
3193 Hitachi H8/300S h8300*-*-*
3194 Matsushita MN10200 w/simulator mn10200-*-*
3195 Matsushita MN10300 w/simulator mn10300-*-*
3196 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3197 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3198 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3199 Mitsubishi D10V w/simulator d10v-*-*
3200 Mitsubishi M32R/D w/simulator m32r-*-elf*
3201 Tsqware Sparclet sparclet-*-*
3202 NEC V850 w/simulator v850-*-*
3204 * New debugging protocols
3206 ARM with RDI protocol arm*-*-*
3207 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3208 DDB and LSI variants of PMON protocol mips*-*-*
3209 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3210 PowerPC with SDS protocol powerpc{,le}-*-eabi
3211 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3215 All configurations can now understand and use the DWARF 2 debugging
3216 format. The choice is automatic, if the symbol file contains DWARF 2
3221 GDB now includes basic Java language support. This support is
3222 only useful with Java compilers that produce native machine code.
3224 * solib-absolute-prefix and solib-search-path
3226 For SunOS and SVR4 shared libraries, you may now set the prefix for
3227 loading absolute shared library symbol files, and the search path for
3228 locating non-absolute shared library symbol files.
3230 * Live range splitting
3232 GDB can now effectively debug code for which GCC has performed live
3233 range splitting as part of its optimization. See gdb/doc/LRS for
3234 more details on the expected format of the stabs information.
3238 GDB's support for the GNU Hurd, including thread debugging, has been
3239 updated to work with current versions of the Hurd.
3243 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3244 instruction set. ARM GDB automatically detects when Thumb
3245 instructions are in use, and adjusts disassembly and backtracing
3250 GDB's MIPS target configurations now handle the MIP16 16-bit
3255 GDB now includes support for overlays; if an executable has been
3256 linked such that multiple sections are based at the same address, GDB
3257 will decide which section to use for symbolic info. You can choose to
3258 control the decision manually, using overlay commands, or implement
3259 additional target-side support and use "overlay load-target" to bring
3260 in the overlay mapping. Do "help overlay" for more detail.
3264 The command "info symbol <address>" displays information about
3265 the symbol at the specified address.
3269 The standard remote protocol now includes an extension that allows
3270 asynchronous collection and display of trace data. This requires
3271 extensive support in the target-side debugging stub. Tracing mode
3272 includes a new interaction mode in GDB and new commands: see the
3273 file tracepoint.c for more details.
3277 Configurations for embedded MIPS now include a simulator contributed
3278 by Cygnus Solutions. The simulator supports the instruction sets
3279 of most MIPS variants.
3283 Sparc configurations may now include the ERC32 simulator contributed
3284 by the European Space Agency. The simulator is not built into
3285 Sparc targets by default; configure with --enable-sim to include it.
3289 For target configurations that may include multiple variants of a
3290 basic architecture (such as MIPS and SH), you may now set the
3291 architecture explicitly. "set arch" sets, "info arch" lists
3292 the possible architectures.
3294 *** Changes in GDB-4.16:
3296 * New native configurations
3298 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3299 M68K NetBSD m68k-*-netbsd*
3300 PowerPC AIX 4.x powerpc-*-aix*
3301 PowerPC MacOS powerpc-*-macos*
3302 PowerPC Windows NT powerpcle-*-cygwin32
3303 RS/6000 AIX 4.x rs6000-*-aix4*
3307 ARM with RDP protocol arm-*-*
3308 I960 with MON960 i960-*-coff
3309 MIPS VxWorks mips*-*-vxworks*
3310 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3311 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3313 Matra Sparclet sparclet-*-*
3317 The powerpc-eabi configuration now includes the PSIM simulator,
3318 contributed by Andrew Cagney, with assistance from Mike Meissner.
3319 PSIM is a very elaborate model of the PowerPC, including not only
3320 basic instruction set execution, but also details of execution unit
3321 performance and I/O hardware. See sim/ppc/README for more details.
3325 GDB now works with Solaris 2.5.
3327 * Windows 95/NT native
3329 GDB will now work as a native debugger on Windows 95 and Windows NT.
3330 To build it from source, you must use the "gnu-win32" environment,
3331 which uses a DLL to emulate enough of Unix to run the GNU tools.
3332 Further information, binaries, and sources are available at
3333 ftp.cygnus.com, under pub/gnu-win32.
3335 * dont-repeat command
3337 If a user-defined command includes the command `dont-repeat', then the
3338 command will not be repeated if the user just types return. This is
3339 useful if the command is time-consuming to run, so that accidental
3340 extra keystrokes don't run the same command many times.
3342 * Send break instead of ^C
3344 The standard remote protocol now includes an option to send a break
3345 rather than a ^C to the target in order to interrupt it. By default,
3346 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3348 * Remote protocol timeout
3350 The standard remote protocol includes a new variable `remotetimeout'
3351 that allows you to set the number of seconds before GDB gives up trying
3352 to read from the target. The default value is 2.
3354 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3356 By default GDB will automatically keep track of objects as they are
3357 loaded and unloaded by the dynamic linker. By using the command `set
3358 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3359 when shared library events occur, thus allowing you to set breakpoints
3360 in shared libraries which are explicitly loaded by the inferior.
3362 Note this feature does not work on hpux8. On hpux9 you must link
3363 /usr/lib/end.o into your program. This feature should work
3364 automatically on hpux10.
3366 * Irix 5.x hardware watchpoint support
3368 Irix 5 configurations now support the use of hardware watchpoints.
3370 * Mips protocol "SYN garbage limit"
3372 When debugging a Mips target using the `target mips' protocol, you
3373 may set the number of characters that GDB will ignore by setting
3374 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3375 every character. The default value is 1050.
3377 * Recording and replaying remote debug sessions
3379 If you set `remotelogfile' to the name of a file, gdb will write to it
3380 a recording of a remote debug session. This recording may then be
3381 replayed back to gdb using "gdbreplay". See gdbserver/README for
3382 details. This is useful when you have a problem with GDB while doing
3383 remote debugging; you can make a recording of the session and send it
3384 to someone else, who can then recreate the problem.
3386 * Speedups for remote debugging
3388 GDB includes speedups for downloading and stepping MIPS systems using
3389 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3390 and more efficient S-record downloading.
3392 * Memory use reductions and statistics collection
3394 GDB now uses less memory and reports statistics about memory usage.
3395 Try the `maint print statistics' command, for example.
3397 *** Changes in GDB-4.15:
3399 * Psymtabs for XCOFF
3401 The symbol reader for AIX GDB now uses partial symbol tables. This
3402 can greatly improve startup time, especially for large executables.
3404 * Remote targets use caching
3406 Remote targets now use a data cache to speed up communication with the
3407 remote side. The data cache could lead to incorrect results because
3408 it doesn't know about volatile variables, thus making it impossible to
3409 debug targets which use memory mapped I/O devices. `set remotecache
3410 off' turns the the data cache off.
3412 * Remote targets may have threads
3414 The standard remote protocol now includes support for multiple threads
3415 in the target system, using new protocol commands 'H' and 'T'. See
3416 gdb/remote.c for details.
3420 If GDB is configured with `--enable-netrom', then it will include
3421 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3422 acts as though it is a bank of ROM on the target board, but you can
3423 write into it over the network. GDB's support consists only of
3424 support for fast loading into the emulated ROM; to debug, you must use
3425 another protocol, such as standard remote protocol. The usual
3426 sequence is something like
3428 target nrom <netrom-hostname>
3430 target remote <netrom-hostname>:1235
3434 GDB now includes support for the Apple Macintosh, as a host only. It
3435 may be run as either an MPW tool or as a standalone application, and
3436 it can debug through the serial port. All the usual GDB commands are
3437 available, but to the target command, you must supply "serial" as the
3438 device type instead of "/dev/ttyXX". See mpw-README in the main
3439 directory for more information on how to build. The MPW configuration
3440 scripts */mpw-config.in support only a few targets, and only the
3441 mips-idt-ecoff target has been tested.
3445 GDB configuration now uses autoconf. This is not user-visible,
3446 but does simplify configuration and building.
3450 GDB now supports hpux10.
3452 *** Changes in GDB-4.14:
3454 * New native configurations
3456 x86 FreeBSD i[345]86-*-freebsd
3457 x86 NetBSD i[345]86-*-netbsd
3458 NS32k NetBSD ns32k-*-netbsd
3459 Sparc NetBSD sparc-*-netbsd
3463 A29K VxWorks a29k-*-vxworks
3464 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3465 CPU32 EST-300 emulator m68*-*-est*
3466 PowerPC ELF powerpc-*-elf
3469 * Alpha OSF/1 support for procfs
3471 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3472 possible to attach to running processes. As the mounting of the /proc
3473 filesystem is optional on the Alpha, GDB automatically determines
3474 the availability of /proc during startup. This can lead to problems
3475 if /proc is unmounted after GDB has been started.
3477 * Arguments to user-defined commands
3479 User commands may accept up to 10 arguments separated by whitespace.
3480 Arguments are accessed within the user command via $arg0..$arg9. A
3483 print $arg0 + $arg1 + $arg2
3485 To execute the command use:
3488 Defines the command "adder" which prints the sum of its three arguments.
3489 Note the arguments are text substitutions, so they may reference variables,
3490 use complex expressions, or even perform inferior function calls.
3492 * New `if' and `while' commands
3494 This makes it possible to write more sophisticated user-defined
3495 commands. Both commands take a single argument, which is the
3496 expression to evaluate, and must be followed by the commands to
3497 execute, one per line, if the expression is nonzero, the list being
3498 terminated by the word `end'. The `if' command list may include an
3499 `else' word, which causes the following commands to be executed only
3500 if the expression is zero.
3502 * Fortran source language mode
3504 GDB now includes partial support for Fortran 77. It will recognize
3505 Fortran programs and can evaluate a subset of Fortran expressions, but
3506 variables and functions may not be handled correctly. GDB will work
3507 with G77, but does not yet know much about symbols emitted by other
3510 * Better HPUX support
3512 Most debugging facilities now work on dynamic executables for HPPAs
3513 running hpux9 or later. You can attach to running dynamically linked
3514 processes, but by default the dynamic libraries will be read-only, so
3515 for instance you won't be able to put breakpoints in them. To change
3516 that behavior do the following before running the program:
3522 This will cause the libraries to be mapped private and read-write.
3523 To revert to the normal behavior, do this:
3529 You cannot set breakpoints or examine data in the library until after
3530 the library is loaded if the function/data symbols do not have
3533 GDB can now also read debug symbols produced by the HP C compiler on
3534 HPPAs (sorry, no C++, Fortran or 68k support).
3536 * Target byte order now dynamically selectable
3538 You can choose which byte order to use with a target system, via the
3539 commands "set endian big" and "set endian little", and you can see the
3540 current setting by using "show endian". You can also give the command
3541 "set endian auto", in which case GDB will use the byte order
3542 associated with the executable. Currently, only embedded MIPS
3543 configurations support dynamic selection of target byte order.
3545 * New DOS host serial code
3547 This version uses DPMI interrupts to handle buffered I/O, so you
3548 no longer need to run asynctsr when debugging boards connected to
3551 *** Changes in GDB-4.13:
3553 * New "complete" command
3555 This lists all the possible completions for the rest of the line, if it
3556 were to be given as a command itself. This is intended for use by emacs.
3558 * Trailing space optional in prompt
3560 "set prompt" no longer adds a space for you after the prompt you set. This
3561 allows you to set a prompt which ends in a space or one that does not.
3563 * Breakpoint hit counts
3565 "info break" now displays a count of the number of times the breakpoint
3566 has been hit. This is especially useful in conjunction with "ignore"; you
3567 can ignore a large number of breakpoint hits, look at the breakpoint info
3568 to see how many times the breakpoint was hit, then run again, ignoring one
3569 less than that number, and this will get you quickly to the last hit of
3572 * Ability to stop printing at NULL character
3574 "set print null-stop" will cause GDB to stop printing the characters of
3575 an array when the first NULL is encountered. This is useful when large
3576 arrays actually contain only short strings.
3578 * Shared library breakpoints
3580 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3581 breakpoints in shared libraries before the executable is run.
3583 * Hardware watchpoints
3585 There is a new hardware breakpoint for the watch command for sparclite
3586 targets. See gdb/sparclite/hw_breakpoint.note.
3588 Hardware watchpoints are also now supported under GNU/Linux.
3592 Annotations have been added. These are for use with graphical interfaces,
3593 and are still experimental. Currently only gdba.el uses these.
3595 * Improved Irix 5 support
3597 GDB now works properly with Irix 5.2.
3599 * Improved HPPA support
3601 GDB now works properly with the latest GCC and GAS.
3603 * New native configurations
3605 Sequent PTX4 i[34]86-sequent-ptx4
3606 HPPA running OSF/1 hppa*-*-osf*
3607 Atari TT running SVR4 m68*-*-sysv4*
3608 RS/6000 LynxOS rs6000-*-lynxos*
3612 OS/9000 i[34]86-*-os9k
3613 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3616 * Hitachi SH7000 and E7000-PC ICE support
3618 There is now support for communicating with the Hitachi E7000-PC ICE.
3619 This is available automatically when GDB is configured for the SH.
3623 As usual, a variety of small fixes and improvements, both generic
3624 and configuration-specific. See the ChangeLog for more detail.
3626 *** Changes in GDB-4.12:
3628 * Irix 5 is now supported
3632 GDB-4.12 on the HPPA has a number of changes which make it unable
3633 to debug the output from the currently released versions of GCC and
3634 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3635 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3636 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3639 *** Changes in GDB-4.11:
3641 * User visible changes:
3645 The "set remotedebug" option is now consistent between the mips remote
3646 target, remote targets using the gdb-specific protocol, UDI (AMD's
3647 debug protocol for the 29k) and the 88k bug monitor. It is now an
3648 integer specifying a debug level (normally 0 or 1, but 2 means more
3649 debugging info for the mips target).
3651 * DEC Alpha native support
3653 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3654 debug info, but GDB works fairly well with the DEC compiler and should
3655 work with a future GCC release. See the README file for a few
3656 Alpha-specific notes.
3658 * Preliminary thread implementation
3660 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3662 * LynxOS native and target support for 386
3664 This release has been hosted on LynxOS 2.2, and also can be configured
3665 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3668 * Improvements in C++ mangling/demangling.
3670 This release has much better g++ debugging, specifically in name
3671 mangling/demangling, virtual function calls, print virtual table,
3672 call methods, ...etc.
3674 *** Changes in GDB-4.10:
3676 * User visible changes:
3678 Remote debugging using the GDB-specific (`target remote') protocol now
3679 supports the `load' command. This is only useful if you have some
3680 other way of getting the stub to the target system, and you can put it
3681 somewhere in memory where it won't get clobbered by the download.
3683 Filename completion now works.
3685 When run under emacs mode, the "info line" command now causes the
3686 arrow to point to the line specified. Also, "info line" prints
3687 addresses in symbolic form (as well as hex).
3689 All vxworks based targets now support a user settable option, called
3690 vxworks-timeout. This option represents the number of seconds gdb
3691 should wait for responses to rpc's. You might want to use this if
3692 your vxworks target is, perhaps, a slow software simulator or happens
3693 to be on the far side of a thin network line.
3697 This release contains support for using a DEC alpha as a GDB host for
3698 cross debugging. Native alpha debugging is not supported yet.
3701 *** Changes in GDB-4.9:
3705 This is the first GDB release which is accompanied by a matching testsuite.
3706 The testsuite requires installation of dejagnu, which should be available
3707 via ftp from most sites that carry GNU software.
3711 'Cfront' style demangling has had its name changed to 'ARM' style, to
3712 emphasize that it was written from the specifications in the C++ Annotated
3713 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3714 disclaimers, it still generated too much confusion with users attempting to
3715 use gdb with AT&T cfront.
3719 GDB now uses a standard remote interface to a simulator library.
3720 So far, the library contains simulators for the Zilog Z8001/2, the
3721 Hitachi H8/300, H8/500 and Super-H.
3723 * New targets supported
3725 H8/300 simulator h8300-hitachi-hms or h8300hms
3726 H8/500 simulator h8500-hitachi-hms or h8500hms
3727 SH simulator sh-hitachi-hms or sh
3728 Z8000 simulator z8k-zilog-none or z8ksim
3729 IDT MIPS board over serial line mips-idt-ecoff
3731 Cross-debugging to GO32 targets is supported. It requires a custom
3732 version of the i386-stub.c module which is integrated with the
3733 GO32 memory extender.
3735 * New remote protocols
3737 MIPS remote debugging protocol.
3739 * New source languages supported
3741 This version includes preliminary support for Chill, a Pascal like language
3742 used by telecommunications companies. Chill support is also being integrated
3743 into the GNU compiler, but we don't know when it will be publically available.
3746 *** Changes in GDB-4.8:
3748 * HP Precision Architecture supported
3750 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3751 version of this support was available as a set of patches from the
3752 University of Utah. GDB does not support debugging of programs
3753 compiled with the HP compiler, because HP will not document their file
3754 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3755 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3757 Many problems in the preliminary version have been fixed.
3759 * Faster and better demangling
3761 We have improved template demangling and fixed numerous bugs in the GNU style
3762 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3763 character types (wchar_t) are now supported. Demangling of each symbol is now
3764 only done once, and is cached when the symbol table for a file is read in.
3765 This results in a small increase in memory usage for C programs, a moderate
3766 increase in memory usage for C++ programs, and a fantastic speedup in
3769 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3770 from the specifications in the Annotated Reference Manual, which AT&T's
3771 compiler does not actually implement.
3773 * G++ multiple inheritance compiler problem
3775 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3776 inheritance lattices was reworked to properly discover ambiguities. We
3777 recently found an example which causes this new algorithm to fail in a
3778 very subtle way, producing bad debug information for those classes.
3779 The file 'gcc.patch' (in this directory) can be applied to gcc to
3780 circumvent the problem. A future GCC release will contain a complete
3783 The previous G++ debug info problem (mentioned below for the gdb-4.7
3784 release) is fixed in gcc version 2.3.2.
3786 * Improved configure script
3788 The `configure' script will now attempt to guess your system type if
3789 you don't supply a host system type. The old scheme of supplying a
3790 host system triplet is preferable over using this. All the magic is
3791 done in the new `config.guess' script. Examine it for details.
3793 We have also brought our configure script much more in line with the FSF's
3794 version. It now supports the --with-xxx options. In particular,
3795 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3796 The resulting GDB will not be able to read arbitrary object file formats --
3797 only the format ``expected'' to be used on the configured target system.
3798 We hope to make this the default in a future release.
3800 * Documentation improvements
3802 There's new internal documentation on how to modify GDB, and how to
3803 produce clean changes to the code. We implore people to read it
3804 before submitting changes.
3806 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3807 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3808 `info' files are also provided. To build `info' files from scratch,
3809 you will need the latest `makeinfo' release, which will be available in
3810 a future texinfo-X.Y release.
3812 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3813 We're not sure exactly which versions have this problem, but it has
3814 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3815 or better. If that isn't possible, there is a patch in
3816 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3817 around this problem.
3821 GDB now supports array constants that can be used in expressions typed in by
3822 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3823 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3826 The new directory `gdb/sparclite' contains a program that demonstrates
3827 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3829 * New native hosts supported
3831 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3832 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3834 * New targets supported
3836 AMD 29k family via UDI a29k-amd-udi or udi29k
3838 * New file formats supported
3840 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3841 HPUX core files, and SCO 3.2v2 core files.
3845 Attaching to processes now works again; thanks for the many bug reports.
3847 We have also stomped on a bunch of core dumps caused by
3848 printf_filtered("%s") problems.
3850 We eliminated a copyright problem on the rpc and ptrace header files
3851 for VxWorks, which was discovered at the last minute during the 4.7
3852 release. You should now be able to build a VxWorks GDB.
3854 You can now interrupt gdb while an attached process is running. This
3855 will cause the attached process to stop, and give control back to GDB.
3857 We fixed problems caused by using too many file descriptors
3858 for reading symbols from object files and libraries. This was
3859 especially a problem for programs that used many (~100) shared
3862 The `step' command now only enters a subroutine if there is line number
3863 information for the subroutine. Otherwise it acts like the `next'
3864 command. Previously, `step' would enter subroutines if there was
3865 any debugging information about the routine. This avoids problems
3866 when using `cc -g1' on MIPS machines.
3868 * Internal improvements
3870 GDB's internal interfaces have been improved to make it easier to support
3871 debugging of multiple languages in the future.
3873 GDB now uses a common structure for symbol information internally.
3874 Minimal symbols (derived from linkage symbols in object files), partial
3875 symbols (from a quick scan of debug information), and full symbols
3876 contain a common subset of information, making it easier to write
3877 shared code that handles any of them.
3879 * New command line options
3881 We now accept --silent as an alias for --quiet.
3885 The memory-mapped-malloc library is now licensed under the GNU Library
3886 General Public License.
3888 *** Changes in GDB-4.7:
3890 * Host/native/target split
3892 GDB has had some major internal surgery to untangle the support for
3893 hosts and remote targets. Now, when you configure GDB for a remote
3894 target, it will no longer load in all of the support for debugging
3895 local programs on the host. When fully completed and tested, this will
3896 ensure that arbitrary host/target combinations are possible.
3898 The primary conceptual shift is to separate the non-portable code in
3899 GDB into three categories. Host specific code is required any time GDB
3900 is compiled on that host, regardless of the target. Target specific
3901 code relates to the peculiarities of the target, but can be compiled on
3902 any host. Native specific code is everything else: it can only be
3903 built when the host and target are the same system. Child process
3904 handling and core file support are two common `native' examples.
3906 GDB's use of /proc for controlling Unix child processes is now cleaner.
3907 It has been split out into a single module under the `target_ops' vector,
3908 plus two native-dependent functions for each system that uses /proc.
3910 * New hosts supported
3912 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3913 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3914 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3916 * New targets supported
3918 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3919 68030 and CPU32 m68030-*-*, m68332-*-*
3921 * New native hosts supported
3923 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3924 (386bsd is not well tested yet)
3925 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3927 * New file formats supported
3929 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3930 supports reading of `a.out.adobe' object files, which are an a.out
3931 format extended with minimal information about multiple sections.
3935 `show copying' is the same as the old `info copying'.
3936 `show warranty' is the same as `info warrantee'.
3937 These were renamed for consistency. The old commands continue to work.
3939 `info handle' is a new alias for `info signals'.
3941 You can now define pre-command hooks, which attach arbitrary command
3942 scripts to any command. The commands in the hook will be executed
3943 prior to the user's command. You can also create a hook which will be
3944 executed whenever the program stops. See gdb.texinfo.
3948 We now deal with Cfront style name mangling, and can even extract type
3949 info from mangled symbols. GDB can automatically figure out which
3950 symbol mangling style your C++ compiler uses.
3952 Calling of methods and virtual functions has been improved as well.
3956 The crash that occured when debugging Sun Ansi-C compiled binaries is
3957 fixed. This was due to mishandling of the extra N_SO stabs output
3960 We also finally got Ultrix 4.2 running in house, and fixed core file
3961 support, with help from a dozen people on the net.
3963 John M. Farrell discovered that the reason that single-stepping was so
3964 slow on all of the Mips based platforms (primarily SGI and DEC) was
3965 that we were trying to demangle and lookup a symbol used for internal
3966 purposes on every instruction that was being stepped through. Changing
3967 the name of that symbol so that it couldn't be mistaken for a C++
3968 mangled symbol sped things up a great deal.
3970 Rich Pixley sped up symbol lookups in general by getting much smarter
3971 about when C++ symbol mangling is necessary. This should make symbol
3972 completion (TAB on the command line) much faster. It's not as fast as
3973 we'd like, but it's significantly faster than gdb-4.6.
3977 A new user controllable variable 'call_scratch_address' can
3978 specify the location of a scratch area to be used when GDB
3979 calls a function in the target. This is necessary because the
3980 usual method of putting the scratch area on the stack does not work
3981 in systems that have separate instruction and data spaces.
3983 We integrated changes to support the 29k UDI (Universal Debugger
3984 Interface), but discovered at the last minute that we didn't have all
3985 of the appropriate copyright paperwork. We are working with AMD to
3986 resolve this, and hope to have it available soon.
3990 We have sped up the remote serial line protocol, especially for targets
3991 with lots of registers. It now supports a new `expedited status' ('T')
3992 message which can be used in place of the existing 'S' status message.
3993 This allows the remote stub to send only the registers that GDB
3994 needs to make a quick decision about single-stepping or conditional
3995 breakpoints, eliminating the need to fetch the entire register set for
3996 each instruction being stepped through.
3998 The GDB remote serial protocol now implements a write-through cache for
3999 registers, only re-reading the registers if the target has run.
4001 There is also a new remote serial stub for SPARC processors. You can
4002 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4003 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4004 processor with a serial port.
4008 Configure.in files have become much easier to read and modify. A new
4009 `table driven' format makes it more obvious what configurations are
4010 supported, and what files each one uses.
4014 There is a new opcodes library which will eventually contain all of the
4015 disassembly routines and opcode tables. At present, it only contains
4016 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4017 disassembler (binutils/objdump) to share these routines.
4019 The libiberty library is now copylefted under the GNU Library General
4020 Public License. This allows more liberal use, and was done so libg++
4021 can use it. This makes no difference to GDB, since the Library License
4022 grants all the rights from the General Public License.
4026 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4027 reference to the stabs symbol info used by the debugger. It is (as far
4028 as we know) the only published document on this fascinating topic. We
4029 encourage you to read it, compare it to the stabs information on your
4030 system, and send improvements on the document in general (to
4031 bug-gdb@prep.ai.mit.edu).
4033 And, of course, many bugs have been fixed.
4036 *** Changes in GDB-4.6:
4038 * Better support for C++ function names
4040 GDB now accepts as input the "demangled form" of C++ overloaded function
4041 names and member function names, and can do command completion on such names
4042 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4043 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4044 Make use of command completion, it is your friend.
4046 GDB also now accepts a variety of C++ mangled symbol formats. They are
4047 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4048 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4049 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4050 for the list of formats.
4052 * G++ symbol mangling problem
4054 Recent versions of gcc have a bug in how they emit debugging information for
4055 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4056 directory) can be applied to gcc to fix the problem. Alternatively, if you
4057 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4058 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4059 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4062 * New 'maintenance' command
4064 All of the commands related to hacking GDB internals have been moved out of
4065 the main command set, and now live behind the 'maintenance' command. This
4066 can also be abbreviated as 'mt'. The following changes were made:
4068 dump-me -> maintenance dump-me
4069 info all-breakpoints -> maintenance info breakpoints
4070 printmsyms -> maintenance print msyms
4071 printobjfiles -> maintenance print objfiles
4072 printpsyms -> maintenance print psymbols
4073 printsyms -> maintenance print symbols
4075 The following commands are new:
4077 maintenance demangle Call internal GDB demangler routine to
4078 demangle a C++ link name and prints the result.
4079 maintenance print type Print a type chain for a given symbol
4081 * Change to .gdbinit file processing
4083 We now read the $HOME/.gdbinit file before processing the argv arguments
4084 (e.g. reading symbol files or core files). This allows global parameters to
4085 be set, which will apply during the symbol reading. The ./.gdbinit is still
4086 read after argv processing.
4088 * New hosts supported
4090 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4092 GNU/Linux support i386-unknown-linux or linux
4094 We are also including code to support the HP/PA running BSD and HPUX. This
4095 is almost guaranteed not to work, as we didn't have time to test or build it
4096 for this release. We are including it so that the more adventurous (or
4097 masochistic) of you can play with it. We also had major problems with the
4098 fact that the compiler that we got from HP doesn't support the -g option.
4101 * New targets supported
4103 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4105 * More smarts about finding #include files
4107 GDB now remembers the compilation directory for all include files, and for
4108 all files from which C is generated (like yacc and lex sources). This
4109 greatly improves GDB's ability to find yacc/lex sources, and include files,
4110 especially if you are debugging your program from a directory different from
4111 the one that contains your sources.
4113 We also fixed a bug which caused difficulty with listing and setting
4114 breakpoints in include files which contain C code. (In the past, you had to
4115 try twice in order to list an include file that you hadn't looked at before.)
4117 * Interesting infernals change
4119 GDB now deals with arbitrary numbers of sections, where the symbols for each
4120 section must be relocated relative to that section's landing place in the
4121 target's address space. This work was needed to support ELF with embedded
4122 stabs used by Solaris-2.0.
4124 * Bug fixes (of course!)
4126 There have been loads of fixes for the following things:
4127 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4128 i960, stabs, DOS(GO32), procfs, etc...
4130 See the ChangeLog for details.
4132 *** Changes in GDB-4.5:
4134 * New machines supported (host and target)
4136 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4138 SGI Irix-4.x mips-sgi-irix4 or iris4
4140 * New malloc package
4142 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4143 Mmalloc is capable of handling mutiple heaps of memory. It is also
4144 capable of saving a heap to a file, and then mapping it back in later.
4145 This can be used to greatly speedup the startup of GDB by using a
4146 pre-parsed symbol table which lives in a mmalloc managed heap. For
4147 more details, please read mmalloc/mmalloc.texi.
4151 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4152 'help info proc' for details.
4154 * MIPS ecoff symbol table format
4156 The code that reads MIPS symbol table format is now supported on all hosts.
4157 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4160 * File name changes for MS-DOS
4162 Many files in the config directories have been renamed to make it easier to
4163 support GDB on MS-DOSe systems (which have very restrictive file name
4164 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4165 environment) is close to working but has some remaining problems. Note
4166 that debugging of DOS programs is not supported, due to limitations
4167 in the ``operating system'', but it can be used to host cross-debugging.
4169 * Cross byte order fixes
4171 Many fixes have been made to support cross debugging of Sparc and MIPS
4172 targets from hosts whose byte order differs.
4174 * New -mapped and -readnow options
4176 If memory-mapped files are available on your system through the 'mmap'
4177 system call, you can use the -mapped option on the `file' or
4178 `symbol-file' commands to cause GDB to write the symbols from your
4179 program into a reusable file. If the program you are debugging is
4180 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4181 Future GDB debugging sessions will notice the presence of this file,
4182 and will quickly map in symbol information from it, rather than reading
4183 the symbol table from the executable program. Using the '-mapped'
4184 option in a GDB `file' or `symbol-file' command has the same effect as
4185 starting GDB with the '-mapped' command-line option.
4187 You can cause GDB to read the entire symbol table immediately by using
4188 the '-readnow' option with any of the commands that load symbol table
4189 information (or on the GDB command line). This makes the command
4190 slower, but makes future operations faster.
4192 The -mapped and -readnow options are typically combined in order to
4193 build a `fred.syms' file that contains complete symbol information.
4194 A simple GDB invocation to do nothing but build a `.syms' file for future
4197 gdb -batch -nx -mapped -readnow programname
4199 The `.syms' file is specific to the host machine on which GDB is run.
4200 It holds an exact image of GDB's internal symbol table. It cannot be
4201 shared across multiple host platforms.
4203 * longjmp() handling
4205 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4206 siglongjmp() without losing control. This feature has not yet been ported to
4207 all systems. It currently works on many 386 platforms, all MIPS-based
4208 platforms (SGI, DECstation, etc), and Sun3/4.
4212 Preliminary work has been put in to support the new Solaris OS from Sun. At
4213 this time, it can control and debug processes, but it is not capable of
4218 As always, many many bug fixes. The major areas were with g++, and mipsread.
4219 People using the MIPS-based platforms should experience fewer mysterious
4220 crashes and trashed symbol tables.
4222 *** Changes in GDB-4.4:
4224 * New machines supported (host and target)
4226 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4228 BSD Reno on Vax vax-dec-bsd
4229 Ultrix on Vax vax-dec-ultrix
4231 * New machines supported (target)
4233 AMD 29000 embedded, using EBMON a29k-none-none
4237 GDB continues to improve its handling of C++. `References' work better.
4238 The demangler has also been improved, and now deals with symbols mangled as
4239 per the Annotated C++ Reference Guide.
4241 GDB also now handles `stabs' symbol information embedded in MIPS
4242 `ecoff' symbol tables. Since the ecoff format was not easily
4243 extensible to handle new languages such as C++, this appeared to be a
4244 good way to put C++ debugging info into MIPS binaries. This option
4245 will be supported in the GNU C compiler, version 2, when it is
4248 * New features for SVR4
4250 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4251 shared libraries. Debugging dynamically linked programs should present
4252 only minor differences from debugging statically linked programs.
4254 The `info proc' command will print out information about any process
4255 on an SVR4 system (including the one you are debugging). At the moment,
4256 it prints the address mappings of the process.
4258 If you bring up GDB on another SVR4 system, please send mail to
4259 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4261 * Better dynamic linking support in SunOS
4263 Reading symbols from shared libraries which contain debugging symbols
4264 now works properly. However, there remain issues such as automatic
4265 skipping of `transfer vector' code during function calls, which
4266 make it harder to debug code in a shared library, than to debug the
4267 same code linked statically.
4271 GDB is now using the latest `getopt' routines from the FSF. This
4272 version accepts the -- prefix for options with long names. GDB will
4273 continue to accept the old forms (-option and +option) as well.
4274 Various single letter abbreviations for options have been explicity
4275 added to the option table so that they won't get overshadowed in the
4276 future by other options that begin with the same letter.
4280 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4281 Many assorted bugs have been handled. Many more remain to be handled.
4282 See the various ChangeLog files (primarily in gdb and bfd) for details.
4285 *** Changes in GDB-4.3:
4287 * New machines supported (host and target)
4289 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4290 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4291 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4293 * Almost SCO Unix support
4295 We had hoped to support:
4296 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4297 (except for core file support), but we discovered very late in the release
4298 that it has problems with process groups that render gdb unusable. Sorry
4299 about that. I encourage people to fix it and post the fixes.
4301 * Preliminary ELF and DWARF support
4303 GDB can read ELF object files on System V Release 4, and can handle
4304 debugging records for C, in DWARF format, in ELF files. This support
4305 is preliminary. If you bring up GDB on another SVR4 system, please
4306 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4311 GDB now uses the latest `readline' library. One user-visible change
4312 is that two tabs will list possible command completions, which previously
4313 required typing M-? (meta-question mark, or ESC ?).
4317 The `stepi' bug that many of you noticed has been squashed.
4318 Many bugs in C++ have been handled. Many more remain to be handled.
4319 See the various ChangeLog files (primarily in gdb and bfd) for details.
4321 * State of the MIPS world (in case you wondered):
4323 GDB can understand the symbol tables emitted by the compilers
4324 supplied by most vendors of MIPS-based machines, including DEC. These
4325 symbol tables are in a format that essentially nobody else uses.
4327 Some versions of gcc come with an assembler post-processor called
4328 mips-tfile. This program is required if you want to do source-level
4329 debugging of gcc-compiled programs. I believe FSF does not ship
4330 mips-tfile with gcc version 1, but it will eventually come with gcc
4333 Debugging of g++ output remains a problem. g++ version 1.xx does not
4334 really support it at all. (If you're lucky, you should be able to get
4335 line numbers and stack traces to work, but no parameters or local
4336 variables.) With some work it should be possible to improve the
4339 When gcc version 2 is released, you will have somewhat better luck.
4340 However, even then you will get confusing results for inheritance and
4343 We will eventually provide full debugging of g++ output on
4344 DECstations. This will probably involve some kind of stabs-in-ecoff
4345 encapulation, but the details have not been worked out yet.
4348 *** Changes in GDB-4.2:
4350 * Improved configuration
4352 Only one copy of `configure' exists now, and it is not self-modifying.
4353 Porting BFD is simpler.
4357 The `step' and `next' commands now only stop at the first instruction
4358 of a source line. This prevents the multiple stops that used to occur
4359 in switch statements, for-loops, etc. `Step' continues to stop if a
4360 function that has debugging information is called within the line.
4364 Lots of small bugs fixed. More remain.
4366 * New host supported (not target)
4368 Intel 386 PC clone running Mach i386-none-mach
4371 *** Changes in GDB-4.1:
4373 * Multiple source language support
4375 GDB now has internal scaffolding to handle several source languages.
4376 It determines the type of each source file from its filename extension,
4377 and will switch expression parsing and number formatting to match the
4378 language of the function in the currently selected stack frame.
4379 You can also specifically set the language to be used, with
4380 `set language c' or `set language modula-2'.
4384 GDB now has preliminary support for the GNU Modula-2 compiler,
4385 currently under development at the State University of New York at
4386 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4387 continue through the fall of 1991 and into 1992.
4389 Other Modula-2 compilers are currently not supported, and attempting to
4390 debug programs compiled with them will likely result in an error as the
4391 symbol table is read. Feel free to work on it, though!
4393 There are hooks in GDB for strict type checking and range checking,
4394 in the `Modula-2 philosophy', but they do not currently work.
4398 GDB can now write to executable and core files (e.g. patch
4399 a variable's value). You must turn this switch on, specify
4400 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4401 by assigning a new value to a variable. Modifications take
4404 * Automatic SunOS shared library reading
4406 When you run your program, GDB automatically determines where its
4407 shared libraries (if any) have been loaded, and reads their symbols.
4408 The `share' command is no longer needed. This also works when
4409 examining core files.
4413 You can specify the number of lines that the `list' command shows.
4416 * New machines supported (host and target)
4418 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4419 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4420 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4422 * New hosts supported (not targets)
4424 IBM RT/PC: romp-ibm-aix or rtpc
4426 * New targets supported (not hosts)
4428 AMD 29000 embedded with COFF a29k-none-coff
4429 AMD 29000 embedded with a.out a29k-none-aout
4430 Ultracomputer remote kernel debug a29k-nyu-kern
4432 * New remote interfaces
4438 *** Changes in GDB-4.0:
4442 Wide output is wrapped at good places to make the output more readable.
4444 Gdb now supports cross-debugging from a host machine of one type to a
4445 target machine of another type. Communication with the target system
4446 is over serial lines. The ``target'' command handles connecting to the
4447 remote system; the ``load'' command will download a program into the
4448 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4449 also supports debugging of realtime processes running under VxWorks,
4450 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4451 stub on the target system.
4453 New CPUs supported include the AMD 29000 and Intel 960.
4455 GDB now reads object files and symbol tables via a ``binary file''
4456 library, which allows a single copy of GDB to debug programs of multiple
4457 object file types such as a.out and coff.
4459 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4460 refcard.dvi and refcard.ps are available to format it).
4463 * Control-Variable user interface simplified
4465 All variables that control the operation of the debugger can be set
4466 by the ``set'' command, and displayed by the ``show'' command.
4468 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4469 ``Show prompt'' produces the response:
4470 Gdb's prompt is new-gdb=>.
4472 What follows are the NEW set commands. The command ``help set'' will
4473 print a complete list of old and new set commands. ``help set FOO''
4474 will give a longer description of the variable FOO. ``show'' will show
4475 all of the variable descriptions and their current settings.
4477 confirm on/off: Enables warning questions for operations that are
4478 hard to recover from, e.g. rerunning the program while
4479 it is already running. Default is ON.
4481 editing on/off: Enables EMACS style command line editing
4482 of input. Previous lines can be recalled with
4483 control-P, the current line can be edited with control-B,
4484 you can search for commands with control-R, etc.
4487 history filename NAME: NAME is where the gdb command history
4488 will be stored. The default is .gdb_history,
4489 or the value of the environment variable
4492 history size N: The size, in commands, of the command history. The
4493 default is 256, or the value of the environment variable
4496 history save on/off: If this value is set to ON, the history file will
4497 be saved after exiting gdb. If set to OFF, the
4498 file will not be saved. The default is OFF.
4500 history expansion on/off: If this value is set to ON, then csh-like
4501 history expansion will be performed on
4502 command line input. The default is OFF.
4504 radix N: Sets the default radix for input and output. It can be set
4505 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4506 in the current radix, so "set radix 10" is always a no-op.
4508 height N: This integer value is the number of lines on a page. Default
4509 is 24, the current `stty rows'' setting, or the ``li#''
4510 setting from the termcap entry matching the environment
4513 width N: This integer value is the number of characters on a line.
4514 Default is 80, the current `stty cols'' setting, or the ``co#''
4515 setting from the termcap entry matching the environment
4518 Note: ``set screensize'' is obsolete. Use ``set height'' and
4519 ``set width'' instead.
4521 print address on/off: Print memory addresses in various command displays,
4522 such as stack traces and structure values. Gdb looks
4523 more ``symbolic'' if you turn this off; it looks more
4524 ``machine level'' with it on. Default is ON.
4526 print array on/off: Prettyprint arrays. New convenient format! Default
4529 print demangle on/off: Print C++ symbols in "source" form if on,
4532 print asm-demangle on/off: Same, for assembler level printouts
4535 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4538 * Support for Epoch Environment.
4540 The epoch environment is a version of Emacs v18 with windowing. One
4541 new command, ``inspect'', is identical to ``print'', except that if you
4542 are running in the epoch environment, the value is printed in its own
4546 * Support for Shared Libraries
4548 GDB can now debug programs and core files that use SunOS shared libraries.
4549 Symbols from a shared library cannot be referenced
4550 before the shared library has been linked with the program (this
4551 happens after you type ``run'' and before the function main() is entered).
4552 At any time after this linking (including when examining core files
4553 from dynamically linked programs), gdb reads the symbols from each
4554 shared library when you type the ``sharedlibrary'' command.
4555 It can be abbreviated ``share''.
4557 sharedlibrary REGEXP: Load shared object library symbols for files
4558 matching a unix regular expression. No argument
4559 indicates to load symbols for all shared libraries.
4561 info sharedlibrary: Status of loaded shared libraries.
4566 A watchpoint stops execution of a program whenever the value of an
4567 expression changes. Checking for this slows down execution
4568 tremendously whenever you are in the scope of the expression, but is
4569 quite useful for catching tough ``bit-spreader'' or pointer misuse
4570 problems. Some machines such as the 386 have hardware for doing this
4571 more quickly, and future versions of gdb will use this hardware.
4573 watch EXP: Set a watchpoint (breakpoint) for an expression.
4575 info watchpoints: Information about your watchpoints.
4577 delete N: Deletes watchpoint number N (same as breakpoints).
4578 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4579 enable N: Re-enables watchpoint number N (same as breakpoints).
4582 * C++ multiple inheritance
4584 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4587 * C++ exception handling
4589 Gdb now supports limited C++ exception handling. Besides the existing
4590 ability to breakpoint on an exception handler, gdb can breakpoint on
4591 the raising of an exception (before the stack is peeled back to the
4594 catch FOO: If there is a FOO exception handler in the dynamic scope,
4595 set a breakpoint to catch exceptions which may be raised there.
4596 Multiple exceptions (``catch foo bar baz'') may be caught.
4598 info catch: Lists all exceptions which may be caught in the
4599 current stack frame.
4602 * Minor command changes
4604 The command ``call func (arg, arg, ...)'' now acts like the print
4605 command, except it does not print or save a value if the function's result
4606 is void. This is similar to dbx usage.
4608 The ``up'' and ``down'' commands now always print the frame they end up
4609 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4610 frames without printing.
4612 * New directory command
4614 'dir' now adds directories to the FRONT of the source search path.
4615 The path starts off empty. Source files that contain debug information
4616 about the directory in which they were compiled can be found even
4617 with an empty path; Sun CC and GCC include this information. If GDB can't
4618 find your source file in the current directory, type "dir .".
4620 * Configuring GDB for compilation
4622 For normal use, type ``./configure host''. See README or gdb.texinfo
4625 GDB now handles cross debugging. If you are remotely debugging between
4626 two different machines, type ``./configure host -target=targ''.
4627 Host is the machine where GDB will run; targ is the machine
4628 where the program that you are debugging will run.