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 * libthread-db-search-path now supports two special values: $sdir and $pdir.
42 $sdir specifies the default system locations of shared libraries.
43 $pdir specifies the directory where the libpthread used by the application
46 GDB no longer looks in $sdir and $pdir after it has searched the directories
47 mentioned in libthread-db-search-path. If you want to search those
48 directories, they must be specified in libthread-db-search-path.
49 The default value of libthread-db-search-path on GNU/Linux and Solaris
50 systems is now "$sdir:$pdir".
52 $pdir is not supported by gdbserver, it is currently ignored.
53 $sdir is supported by gdbserver.
55 * New configure option --with-iconv-bin.
56 When using the internationalization support like the one in the GNU C
57 library, GDB will invoke the "iconv" program to get a list of supported
58 character sets. If this program lives in a non-standard location, one can
59 use this option to specify where to find it.
61 * When natively debugging programs on PowerPC BookE processors running
62 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
63 watchpoints, which specify a mask in addition to an address to watch.
64 The mask specifies that some bits of an address (the bits which are
65 reset in the mask) should be ignored when matching the address accessed
66 by the inferior against the watchpoint address. See the "PowerPC Embedded"
67 section in the user manual for more details.
69 * The new option --once causes GDBserver to stop listening for connections once
70 the first connection is made. The listening port used by GDBserver will
71 become available after that.
73 * New commands "info macros", and "info definitions" have been added.
77 watch EXPRESSION mask MASK_VALUE
78 The watch command now supports the mask argument which allows creation
79 of masked watchpoints, if the current architecture supports this feature.
81 info auto-load-scripts [REGEXP]
82 This command was formerly named "maintenance print section-scripts".
83 It is now generally useful and is no longer a maintenance-only command.
85 * Tracepoints can now be enabled and disabled at any time after a trace
86 experiment has been started using the standard "enable" and "disable"
87 commands. It is now possible to start a trace experiment with no enabled
88 tracepoints; GDB will display a warning, but will allow the experiment to
89 begin, assuming that tracepoints will be enabled as needed while the trace
96 Dynamically enable a tracepoint in a started trace experiment.
100 Dynamically disable a tracepoint in a started trace experiment.
102 * Dcache size (number of lines) and line-size are now runtime-configurable
103 via "set dcache line" and "set dcache line-size" commands.
107 Texas Instruments TMS320C6x tic6x-*-*
109 *** Changes in GDB 7.3.1
111 * The build failure for NetBSD and OpenBSD targets have now been fixed.
113 *** Changes in GDB 7.3
115 * GDB has a new command: "thread find [REGEXP]".
116 It finds the thread id whose name, target id, or thread extra info
117 matches the given regular expression.
119 * The "catch syscall" command now works on mips*-linux* targets.
121 * The -data-disassemble MI command now supports modes 2 and 3 for
122 dumping the instruction opcodes.
124 * New command line options
126 -data-directory DIR Specify DIR as the "data-directory".
127 This is mostly for testing purposes.
129 * The "maint set python auto-load on|off" command has been renamed to
130 "set auto-load-scripts on|off".
132 * GDB has a new command: "set directories".
133 It is like the "dir" command except that it replaces the
134 source path list instead of augmenting it.
136 * GDB now understands thread names.
138 On GNU/Linux, "info threads" will display the thread name as set by
139 prctl or pthread_setname_np.
141 There is also a new command, "thread name", which can be used to
142 assign a name internally for GDB to display.
145 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
146 has been integrated into GDB.
150 ** The function gdb.Write now accepts an optional keyword 'stream'.
151 This keyword, when provided, will direct the output to either
152 stdout, stderr, or GDB's logging output.
154 ** Parameters can now be be sub-classed in Python, and in particular
155 you may implement the get_set_doc and get_show_doc functions.
156 This improves how Parameter set/show documentation is processed
157 and allows for more dynamic content.
159 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
160 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
161 have an is_valid method.
163 ** Breakpoints can now be sub-classed in Python, and in particular
164 you may implement a 'stop' function that is executed each time
165 the inferior reaches that breakpoint.
167 ** New function gdb.lookup_global_symbol looks up a global symbol.
169 ** GDB values in Python are now callable if the value represents a
170 function. For example, if 'some_value' represents a function that
171 takes two integer parameters and returns a value, you can call
172 that function like so:
174 result = some_value (10,20)
176 ** Module gdb.types has been added.
177 It contains a collection of utilities for working with gdb.Types objects:
178 get_basic_type, has_field, make_enum_dict.
180 ** Module gdb.printing has been added.
181 It contains utilities for writing and registering pretty-printers.
182 New classes: PrettyPrinter, SubPrettyPrinter,
183 RegexpCollectionPrettyPrinter.
184 New function: register_pretty_printer.
186 ** New commands "info pretty-printers", "enable pretty-printer" and
187 "disable pretty-printer" have been added.
189 ** gdb.parameter("directories") is now available.
191 ** New function gdb.newest_frame returns the newest frame in the
194 ** The gdb.InferiorThread class has a new "name" attribute. This
195 holds the thread's name.
197 ** Python Support for Inferior events.
198 Python scripts can add observers to be notified of events
199 occurring in the process being debugged.
200 The following events are currently supported:
201 - gdb.events.cont Continue event.
202 - gdb.events.exited Inferior exited event.
203 - gdb.events.stop Signal received, and Breakpoint hit events.
207 ** GDB now puts template parameters in scope when debugging in an
208 instantiation. For example, if you have:
210 template<int X> int func (void) { return X; }
212 then if you step into func<5>, "print X" will show "5". This
213 feature requires proper debuginfo support from the compiler; it
214 was added to GCC 4.5.
216 ** The motion commands "next", "finish", "until", and "advance" now
217 work better when exceptions are thrown. In particular, GDB will
218 no longer lose control of the inferior; instead, the GDB will
219 stop the inferior at the point at which the exception is caught.
220 This functionality requires a change in the exception handling
221 code that was introduced in GCC 4.5.
223 * GDB now follows GCC's rules on accessing volatile objects when
224 reading or writing target state during expression evaluation.
225 One notable difference to prior behavior is that "print x = 0"
226 no longer generates a read of x; the value of the assignment is
227 now always taken directly from the value being assigned.
229 * GDB now has some support for using labels in the program's source in
230 linespecs. For instance, you can use "advance label" to continue
231 execution to a label.
233 * GDB now has support for reading and writing a new .gdb_index
234 section. This section holds a fast index of DWARF debugging
235 information and can be used to greatly speed up GDB startup and
236 operation. See the documentation for `save gdb-index' for details.
238 * The "watch" command now accepts an optional "-location" argument.
239 When used, this causes GDB to watch the memory referred to by the
240 expression. Such a watchpoint is never deleted due to it going out
243 * GDB now supports thread debugging of core dumps on GNU/Linux.
245 GDB now activates thread debugging using the libthread_db library
246 when debugging GNU/Linux core dumps, similarly to when debugging
247 live processes. As a result, when debugging a core dump file, GDB
248 is now able to display pthread_t ids of threads. For example, "info
249 threads" shows the same output as when debugging the process when it
250 was live. In earlier releases, you'd see something like this:
253 * 1 LWP 6780 main () at main.c:10
255 While now you see this:
258 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
260 It is also now possible to inspect TLS variables when debugging core
263 When debugging a core dump generated on a machine other than the one
264 used to run GDB, you may need to point GDB at the correct
265 libthread_db library with the "set libthread-db-search-path"
266 command. See the user manual for more details on this command.
268 * When natively debugging programs on PowerPC BookE processors running
269 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
270 which stop execution of the inferior whenever it executes an instruction
271 at any address within the specified range. See the "PowerPC Embedded"
272 section in the user manual for more details.
274 * New features in the GDB remote stub, GDBserver
276 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
277 and i686 LynxOS (version 5.x).
279 ** GDBserver is now supported on Blackfin Linux.
281 * New native configurations
283 ia64 HP-UX ia64-*-hpux*
287 Analog Devices, Inc. Blackfin Processor bfin-*
289 * Ada task switching is now supported on sparc-elf targets when
290 debugging a program using the Ravenscar Profile. For more information,
291 see the "Tasking Support when using the Ravenscar Profile" section
292 in the GDB user manual.
294 * Guile support was removed.
296 * New features in the GNU simulator
298 ** The --map-info flag lists all known core mappings.
300 ** CFI flashes may be simulated via the "cfi" device.
302 *** Changes in GDB 7.2
304 * Shared library support for remote targets by default
306 When GDB is configured for a generic, non-OS specific target, like
307 for example, --target=arm-eabi or one of the many *-*-elf targets,
308 GDB now queries remote stubs for loaded shared libraries using the
309 `qXfer:libraries:read' packet. Previously, shared library support
310 was always disabled for such configurations.
314 ** Argument Dependent Lookup (ADL)
316 In C++ ADL lookup directs function search to the namespaces of its
317 arguments even if the namespace has not been imported.
327 Here the compiler will search for `foo' in the namespace of 'b'
328 and find A::foo. GDB now supports this. This construct is commonly
329 used in the Standard Template Library for operators.
331 ** Improved User Defined Operator Support
333 In addition to member operators, GDB now supports lookup of operators
334 defined in a namespace and imported with a `using' directive, operators
335 defined in the global scope, operators imported implicitly from an
336 anonymous namespace, and the ADL operators mentioned in the previous
338 GDB now also supports proper overload resolution for all the previously
339 mentioned flavors of operators.
341 ** static const class members
343 Printing of static const class members that are initialized in the
344 class definition has been fixed.
346 * Windows Thread Information Block access.
348 On Windows targets, GDB now supports displaying the Windows Thread
349 Information Block (TIB) structure. This structure is visible either
350 by using the new command `info w32 thread-information-block' or, by
351 dereferencing the new convenience variable named `$_tlb', a
352 thread-specific pointer to the TIB. This feature is also supported
353 when remote debugging using GDBserver.
357 Static tracepoints are calls in the user program into a tracing
358 library. One such library is a port of the LTTng kernel tracer to
359 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
360 When debugging with GDBserver, GDB now supports combining the GDB
361 tracepoint machinery with such libraries. For example: the user can
362 use GDB to probe a static tracepoint marker (a call from the user
363 program into the tracing library) with the new "strace" command (see
364 "New commands" below). This creates a "static tracepoint" in the
365 breakpoint list, that can be manipulated with the same feature set
366 as fast and regular tracepoints. E.g., collect registers, local and
367 global variables, collect trace state variables, and define
368 tracepoint conditions. In addition, the user can collect extra
369 static tracepoint marker specific data, by collecting the new
370 $_sdata internal variable. When analyzing the trace buffer, you can
371 inspect $_sdata like any other variable available to GDB. For more
372 information, see the "Tracepoints" chapter in GDB user manual. New
373 remote packets have been defined to support static tracepoints, see
374 the "New remote packets" section below.
376 * Better reconstruction of tracepoints after disconnected tracing
378 GDB will attempt to download the original source form of tracepoint
379 definitions when starting a trace run, and then will upload these
380 upon reconnection to the target, resulting in a more accurate
381 reconstruction of the tracepoints that are in use on the target.
385 You can now exercise direct control over the ways that GDB can
386 affect your program. For instance, you can disallow the setting of
387 breakpoints, so that the program can run continuously (assuming
388 non-stop mode). In addition, the "observer" variable is available
389 to switch all of the different controls; in observer mode, GDB
390 cannot affect the target's behavior at all, which is useful for
391 tasks like diagnosing live systems in the field.
393 * The new convenience variable $_thread holds the number of the
400 Return the address of the Windows Thread Information Block of a given thread.
404 In response to several of the tracepoint packets, the target may now
405 also respond with a number of intermediate `qRelocInsn' request
406 packets before the final result packet, to have GDB handle
407 relocating an instruction to execute at a different address. This
408 is particularly useful for stubs that support fast tracepoints. GDB
409 reports support for this feature in the qSupported packet.
413 List static tracepoint markers in the target program.
417 List static tracepoint markers at a given address in the target
420 qXfer:statictrace:read
422 Read the static trace data collected (by a `collect $_sdata'
423 tracepoint action). The remote stub reports support for this packet
424 to gdb's qSupported query.
428 Send the current settings of GDB's permission flags.
432 Send part of the source (textual) form of a tracepoint definition,
433 which includes location, conditional, and action list.
435 * The source command now accepts a -s option to force searching for the
436 script in the source search path even if the script name specifies
439 * New features in the GDB remote stub, GDBserver
441 - GDBserver now support tracepoints (including fast tracepoints, and
442 static tracepoints). The feature is currently supported by the
443 i386-linux and amd64-linux builds. See the "Tracepoints support
444 in gdbserver" section in the manual for more information.
446 GDBserver JIT compiles the tracepoint's conditional agent
447 expression bytecode into native code whenever possible for low
448 overhead dynamic tracepoints conditionals. For such tracepoints,
449 an expression that examines program state is evaluated when the
450 tracepoint is reached, in order to determine whether to capture
451 trace data. If the condition is simple and false, processing the
452 tracepoint finishes very quickly and no data is gathered.
454 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
455 for static tracepoints support.
457 - GDBserver now supports x86_64 Windows 64-bit debugging.
459 * GDB now sends xmlRegisters= in qSupported packet to indicate that
460 it understands register description.
462 * The --batch flag now disables pagination and queries.
464 * X86 general purpose registers
466 GDB now supports reading/writing byte, word and double-word x86
467 general purpose registers directly. This means you can use, say,
468 $ah or $ax to refer, respectively, to the byte register AH and
469 16-bit word register AX that are actually portions of the 32-bit
470 register EAX or 64-bit register RAX.
472 * The `commands' command now accepts a range of breakpoints to modify.
473 A plain `commands' following a command that creates multiple
474 breakpoints affects all the breakpoints set by that command. This
475 applies to breakpoints set by `rbreak', and also applies when a
476 single `break' command creates multiple breakpoints (e.g.,
477 breakpoints on overloaded c++ functions).
479 * The `rbreak' command now accepts a filename specification as part of
480 its argument, limiting the functions selected by the regex to those
481 in the specified file.
483 * Support for remote debugging Windows and SymbianOS shared libraries
484 from Unix hosts has been improved. Non Windows GDB builds now can
485 understand target reported file names that follow MS-DOS based file
486 system semantics, such as file names that include drive letters and
487 use the backslash character as directory separator. This makes it
488 possible to transparently use the "set sysroot" and "set
489 solib-search-path" on Unix hosts to point as host copies of the
490 target's shared libraries. See the new command "set
491 target-file-system-kind" described below, and the "Commands to
492 specify files" section in the user manual for more information.
496 eval template, expressions...
497 Convert the values of one or more expressions under the control
498 of the string template to a command line, and call it.
500 set target-file-system-kind unix|dos-based|auto
501 show target-file-system-kind
502 Set or show the assumed file system kind for target reported file
505 save breakpoints <filename>
506 Save all current breakpoint definitions to a file suitable for use
507 in a later debugging session. To read the saved breakpoint
508 definitions, use the `source' command.
510 `save tracepoints' is a new alias for `save-tracepoints'. The latter
513 info static-tracepoint-markers
514 Display information about static tracepoint markers in the target.
516 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
517 Define a static tracepoint by probing a marker at the given
518 function, line, address, or marker ID.
522 Enable and disable observer mode.
524 set may-write-registers on|off
525 set may-write-memory on|off
526 set may-insert-breakpoints on|off
527 set may-insert-tracepoints on|off
528 set may-insert-fast-tracepoints on|off
529 set may-interrupt on|off
530 Set individual permissions for GDB effects on the target. Note that
531 some of these settings can have undesirable or surprising
532 consequences, particularly when changed in the middle of a session.
533 For instance, disabling the writing of memory can prevent
534 breakpoints from being inserted, cause single-stepping to fail, or
535 even crash your program, if you disable after breakpoints have been
536 inserted. However, GDB should not crash.
538 set record memory-query on|off
539 show record memory-query
540 Control whether to stop the inferior if memory changes caused
541 by an instruction cannot be recorded.
546 The disassemble command now supports "start,+length" form of two arguments.
550 ** GDB now provides a new directory location, called the python directory,
551 where Python scripts written for GDB can be installed. The location
552 of that directory is <data-directory>/python, where <data-directory>
553 is the GDB data directory. For more details, see section `Scripting
554 GDB using Python' in the manual.
556 ** The GDB Python API now has access to breakpoints, symbols, symbol
557 tables, program spaces, inferiors, threads and frame's code blocks.
558 Additionally, GDB Parameters can now be created from the API, and
559 manipulated via set/show in the CLI.
561 ** New functions gdb.target_charset, gdb.target_wide_charset,
562 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
564 ** New exception gdb.GdbError.
566 ** Pretty-printers are now also looked up in the current program space.
568 ** Pretty-printers can now be individually enabled and disabled.
570 ** GDB now looks for names of Python scripts to auto-load in a
571 special section named `.debug_gdb_scripts', in addition to looking
572 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
574 * Tracepoint actions were unified with breakpoint commands. In particular,
575 there are no longer differences in "info break" output for breakpoints and
576 tracepoints and the "commands" command can be used for both tracepoints and
581 ARM Symbian arm*-*-symbianelf*
583 * D language support.
584 GDB now supports debugging programs written in the D programming
587 * GDB now supports the extended ptrace interface for PowerPC which is
588 available since Linux kernel version 2.6.34. This automatically enables
589 any hardware breakpoints and additional hardware watchpoints available in
590 the processor. The old ptrace interface exposes just one hardware
591 watchpoint and no hardware breakpoints.
593 * GDB is now able to use the Data Value Compare (DVC) register available on
594 embedded PowerPC processors to implement in hardware simple watchpoint
595 conditions of the form:
597 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
599 This works in native GDB running on Linux kernels with the extended ptrace
600 interface mentioned above.
602 *** Changes in GDB 7.1
608 GDB now supports importing of namespaces in C++. This enables the
609 user to inspect variables from imported namespaces. Support for
610 namepace aliasing has also been added. So, if a namespace is
611 aliased in the current scope (e.g. namepace C=A; ) the user can
612 print variables using the alias (e.g. (gdb) print C::x).
616 All known bugs relating to the printing of virtual base class were
617 fixed. It is now possible to call overloaded static methods using a
622 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
623 and reinterpret_cast<> are now handled by the C++ expression parser.
627 Xilinx MicroBlaze microblaze-*-*
632 Xilinx MicroBlaze microblaze
635 * Multi-program debugging.
637 GDB now has support for multi-program (a.k.a. multi-executable or
638 multi-exec) debugging. This allows for debugging multiple inferiors
639 simultaneously each running a different program under the same GDB
640 session. See "Debugging Multiple Inferiors and Programs" in the
641 manual for more information. This implied some user visible changes
642 in the multi-inferior support. For example, "info inferiors" now
643 lists inferiors that are not running yet or that have exited
644 already. See also "New commands" and "New options" below.
646 * New tracing features
648 GDB's tracepoint facility now includes several new features:
650 ** Trace state variables
652 GDB tracepoints now include support for trace state variables, which
653 are variables managed by the target agent during a tracing
654 experiment. They are useful for tracepoints that trigger each
655 other, so for instance one tracepoint can count hits in a variable,
656 and then a second tracepoint has a condition that is true when the
657 count reaches a particular value. Trace state variables share the
658 $-syntax of GDB convenience variables, and can appear in both
659 tracepoint actions and condition expressions. Use the "tvariable"
660 command to create, and "info tvariables" to view; see "Trace State
661 Variables" in the manual for more detail.
665 GDB now includes an option for defining fast tracepoints, which
666 targets may implement more efficiently, such as by installing a jump
667 into the target agent rather than a trap instruction. The resulting
668 speedup can be by two orders of magnitude or more, although the
669 tradeoff is that some program locations on some target architectures
670 might not allow fast tracepoint installation, for instance if the
671 instruction to be replaced is shorter than the jump. To request a
672 fast tracepoint, use the "ftrace" command, with syntax identical to
673 the regular trace command.
675 ** Disconnected tracing
677 It is now possible to detach GDB from the target while it is running
678 a trace experiment, then reconnect later to see how the experiment
679 is going. In addition, a new variable disconnected-tracing lets you
680 tell the target agent whether to continue running a trace if the
681 connection is lost unexpectedly.
685 GDB now has the ability to save the trace buffer into a file, and
686 then use that file as a target, similarly to you can do with
687 corefiles. You can select trace frames, print data that was
688 collected in them, and use tstatus to display the state of the
689 tracing run at the moment that it was saved. To create a trace
690 file, use "tsave <filename>", and to use it, do "target tfile
693 ** Circular trace buffer
695 You can ask the target agent to handle the trace buffer as a
696 circular buffer, discarding the oldest trace frames to make room for
697 newer ones, by setting circular-trace-buffer to on. This feature may
698 not be available for all target agents.
703 The disassemble command, when invoked with two arguments, now requires
704 the arguments to be comma-separated.
707 The info variables command now displays variable definitions. Files
708 which only declare a variable are not shown.
711 The source command is now capable of sourcing Python scripts.
712 This feature is dependent on the debugger being build with Python
715 Related to this enhancement is also the introduction of a new command
716 "set script-extension" (see below).
718 * New commands (for set/show, see "New options" below)
720 record save [<FILENAME>]
721 Save a file (in core file format) containing the process record
722 execution log for replay debugging at a later time.
724 record restore <FILENAME>
725 Restore the process record execution log that was saved at an
726 earlier time, for replay debugging.
728 add-inferior [-copies <N>] [-exec <FILENAME>]
731 clone-inferior [-copies <N>] [ID]
732 Make a new inferior ready to execute the same program another
738 maint info program-spaces
739 List the program spaces loaded into GDB.
741 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
742 show remote interrupt-sequence
743 Allow the user to select one of ^C, a BREAK signal or BREAK-g
744 as the sequence to the remote target in order to interrupt the execution.
745 Ctrl-C is a default. Some system prefers BREAK which is high level of
746 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
747 Magic SysRq g. It is BREAK signal and character 'g'.
749 set remote interrupt-on-connect [on | off]
750 show remote interrupt-on-connect
751 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
752 remote target when gdb connects to it. This is needed when you debug
755 set remotebreak [on | off]
757 Deprecated. Use "set/show remote interrupt-sequence" instead.
759 tvariable $NAME [ = EXP ]
760 Create or modify a trace state variable.
763 List trace state variables and their values.
765 delete tvariable $NAME ...
766 Delete one or more trace state variables.
769 Evaluate the given expressions without collecting anything into the
770 trace buffer. (Valid in tracepoint actions only.)
772 ftrace FN / FILE:LINE / *ADDR
773 Define a fast tracepoint at the given function, line, or address.
775 * New expression syntax
777 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
778 GDB now parses 0b101010 identically with 42.
782 set follow-exec-mode new|same
783 show follow-exec-mode
784 Control whether GDB reuses the same inferior across an exec call or
785 creates a new one. This is useful to be able to restart the old
786 executable after the inferior having done an exec call.
788 set default-collect EXPR, ...
790 Define a list of expressions to be collected at each tracepoint.
791 This is a useful way to ensure essential items are not overlooked,
792 such as registers or a critical global variable.
794 set disconnected-tracing
795 show disconnected-tracing
796 If set to 1, the target is instructed to continue tracing if it
797 loses its connection to GDB. If 0, the target is to stop tracing
800 set circular-trace-buffer
801 show circular-trace-buffer
802 If set to on, the target is instructed to use a circular trace buffer
803 and discard the oldest trace frames instead of stopping the trace due
804 to a full trace buffer. If set to off, the trace stops when the buffer
805 fills up. Some targets may not support this.
807 set script-extension off|soft|strict
808 show script-extension
809 If set to "off", the debugger does not perform any script language
810 recognition, and all sourced files are assumed to be GDB scripts.
811 If set to "soft" (the default), files are sourced according to
812 filename extension, falling back to GDB scripts if the first
814 If set to "strict", files are sourced according to filename extension.
816 set ada trust-PAD-over-XVS on|off
817 show ada trust-PAD-over-XVS
818 If off, activate a workaround against a bug in the debugging information
819 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
820 the GCC sources for more information about the GNAT encoding and
821 PAD types in particular). It is always safe to set this option to
822 off, but this introduces a slight performance penalty. The default
825 * Python API Improvements
827 ** GDB provides the new class gdb.LazyString. This is useful in
828 some pretty-printing cases. The new method gdb.Value.lazy_string
829 provides a simple way to create objects of this type.
831 ** The fields returned by gdb.Type.fields now have an
832 `is_base_class' attribute.
834 ** The new method gdb.Type.range returns the range of an array type.
836 ** The new method gdb.parse_and_eval can be used to parse and
837 evaluate an expression.
842 Define a trace state variable.
845 Get the current value of a trace state variable.
848 Set desired tracing behavior upon disconnection.
851 Set the trace buffer to be linear or circular.
854 Get data about the tracepoints currently in use.
858 Process record now works correctly with hardware watchpoints.
860 Multiple bug fixes have been made to the mips-irix port, making it
861 much more reliable. In particular:
862 - Debugging threaded applications is now possible again. Previously,
863 GDB would hang while starting the program, or while waiting for
864 the program to stop at a breakpoint.
865 - Attaching to a running process no longer hangs.
866 - An error occurring while loading a core file has been fixed.
867 - Changing the value of the PC register now works again. This fixes
868 problems observed when using the "jump" command, or when calling
869 a function from GDB, or even when assigning a new value to $pc.
870 - With the "finish" and "return" commands, the return value for functions
871 returning a small array is now correctly printed.
872 - It is now possible to break on shared library code which gets executed
873 during a shared library init phase (code executed while executing
874 their .init section). Previously, the breakpoint would have no effect.
875 - GDB is now able to backtrace through the signal handler for
876 non-threaded programs.
878 PIE (Position Independent Executable) programs debugging is now supported.
879 This includes debugging execution of PIC (Position Independent Code) shared
880 libraries although for that, it should be possible to run such libraries as an
883 *** Changes in GDB 7.0
885 * GDB now has an interface for JIT compilation. Applications that
886 dynamically generate code can create symbol files in memory and register
887 them with GDB. For users, the feature should work transparently, and
888 for JIT developers, the interface is documented in the GDB manual in the
889 "JIT Compilation Interface" chapter.
891 * Tracepoints may now be conditional. The syntax is as for
892 breakpoints; either an "if" clause appended to the "trace" command,
893 or the "condition" command is available. GDB sends the condition to
894 the target for evaluation using the same bytecode format as is used
895 for tracepoint actions.
897 * The disassemble command now supports: an optional /r modifier, print the
898 raw instructions in hex as well as in symbolic form, and an optional /m
899 modifier to print mixed source+assembly.
901 * Process record and replay
903 In a architecture environment that supports ``process record and
904 replay'', ``process record and replay'' target can record a log of
905 the process execution, and replay it with both forward and reverse
908 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
909 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
910 set execution-direction {forward|reverse}, for targets that support
913 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
914 feature is available with a native GDB running on kernel version
917 * GDB now has support for multi-byte and wide character sets on the
918 target. Strings whose character type is wchar_t, char16_t, or
919 char32_t are now correctly printed. GDB supports wide- and unicode-
920 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
921 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
922 `printf'. This feature requires iconv to work properly; if your
923 system does not have a working iconv, GDB can use GNU libiconv. See
924 the installation instructions for more information.
926 * GDB now supports automatic retrieval of shared library files from
927 remote targets. To use this feature, specify a system root that begins
928 with the `remote:' prefix, either via the `set sysroot' command or via
929 the `--with-sysroot' configure-time option.
931 * "info sharedlibrary" now takes an optional regex of libraries to show,
932 and it now reports if a shared library has no debugging information.
934 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
935 now complete on file names.
937 * When completing in expressions, gdb will attempt to limit
938 completions to allowable structure or union fields, where appropriate.
939 For instance, consider:
941 # struct example { int f1; double f2; };
942 # struct example variable;
945 If the user types TAB at the end of this command line, the available
946 completions will be "f1" and "f2".
948 * Inlined functions are now supported. They show up in backtraces, and
949 the "step", "next", and "finish" commands handle them automatically.
951 * GDB now supports the token-splicing (##) and stringification (#)
952 operators when expanding macros. It also supports variable-arity
955 * GDB now supports inspecting extra signal information, exported by
956 the new $_siginfo convenience variable. The feature is currently
957 implemented on linux ARM, i386 and amd64.
959 * GDB can now display the VFP floating point registers and NEON vector
960 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
961 can provide these registers (requires Linux 2.6.30 or later). Remote
962 and simulator targets may also provide them.
967 Search memory for a sequence of bytes.
970 Turn off `+'/`-' protocol acknowledgments to permit more efficient
971 operation over reliable transport links. Use of this packet is
972 controlled by the `set remote noack-packet' command.
975 Kill the process with the specified process ID. Use this in preference
976 to `k' when multiprocess protocol extensions are supported.
979 Obtains additional operating system information
983 Read or write additional signal information.
985 * Removed remote protocol undocumented extension
987 An undocumented extension to the remote protocol's `S' stop reply
988 packet that permited the stub to pass a process id was removed.
989 Remote servers should use the `T' stop reply packet instead.
991 * GDB now supports multiple function calling conventions according to the
992 DWARF-2 DW_AT_calling_convention function attribute.
994 * The SH target utilizes the aforementioned change to distinguish between gcc
995 and Renesas calling convention. It also adds the new CLI commands
996 `set/show sh calling-convention'.
998 * GDB can now read compressed debug sections, as produced by GNU gold
999 with the --compress-debug-sections=zlib flag.
1001 * 64-bit core files are now supported on AIX.
1003 * Thread switching is now supported on Tru64.
1005 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1006 which will be allocated using malloc later in program execution.
1008 * The qXfer:libraries:read remote procotol packet now allows passing a
1009 list of section offsets.
1011 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1012 conditions handling signals delivered during attach or thread creation
1013 have also been fixed.
1015 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1016 From the user's standpoint, all unqualified instances of True and False
1017 are treated as the standard definitions, regardless of context.
1019 * GDB now parses C++ symbol and type names more flexibly. For
1022 template<typename T> class C { };
1025 GDB will now correctly handle all of:
1027 ptype C<char const *>
1028 ptype C<char const*>
1029 ptype C<const char *>
1030 ptype C<const char*>
1032 * New features in the GDB remote stub, gdbserver
1034 - The "--wrapper" command-line argument tells gdbserver to use a
1035 wrapper program to launch programs for debugging.
1037 - On PowerPC and S/390 targets, it is now possible to use a single
1038 gdbserver executable to debug both 32-bit and 64-bit programs.
1039 (This requires gdbserver itself to be built as a 64-bit executable.)
1041 - gdbserver uses the new noack protocol mode for TCP connections to
1042 reduce communications latency, if also supported and enabled in GDB.
1044 - Support for the sparc64-linux-gnu target is now included in
1047 - The amd64-linux build of gdbserver now supports debugging both
1048 32-bit and 64-bit programs.
1050 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1051 now support hardware watchpoints, and will use them automatically
1056 GDB now has support for scripting using Python. Whether this is
1057 available is determined at configure time.
1059 New GDB commands can now be written in Python.
1061 * Ada tasking support
1063 Ada tasks can now be inspected in GDB. The following commands have
1067 Print the list of Ada tasks.
1069 Print detailed information about task number N.
1071 Print the task number of the current task.
1073 Switch the context of debugging to task number N.
1075 * Support for user-defined prefixed commands. The "define" command can
1076 add new commands to existing prefixes, e.g. "target".
1078 * Multi-inferior, multi-process debugging.
1080 GDB now has generalized support for multi-inferior debugging. See
1081 "Debugging Multiple Inferiors" in the manual for more information.
1082 Although availability still depends on target support, the command
1083 set is more uniform now. The GNU/Linux specific multi-forks support
1084 has been migrated to this new framework. This implied some user
1085 visible changes; see "New commands" and also "Removed commands"
1088 * Target descriptions can now describe the target OS ABI. See the
1089 "Target Description Format" section in the user manual for more
1092 * Target descriptions can now describe "compatible" architectures
1093 to indicate that the target can execute applications for a different
1094 architecture in addition to those for the main target architecture.
1095 See the "Target Description Format" section in the user manual for
1098 * Multi-architecture debugging.
1100 GDB now includes general supports for debugging applications on
1101 hybrid systems that use more than one single processor architecture
1102 at the same time. Each such hybrid architecture still requires
1103 specific support to be added. The only hybrid architecture supported
1104 in this version of GDB is the Cell Broadband Engine.
1106 * GDB now supports integrated debugging of Cell/B.E. applications that
1107 use both the PPU and SPU architectures. To enable support for hybrid
1108 Cell/B.E. debugging, you need to configure GDB to support both the
1109 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1110 --enable-targets configure option.
1112 * Non-stop mode debugging.
1114 For some targets, GDB now supports an optional mode of operation in
1115 which you can examine stopped threads while other threads continue
1116 to execute freely. This is referred to as non-stop mode, with the
1117 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1118 section in the user manual for more information.
1120 To be able to support remote non-stop debugging, a remote stub needs
1121 to implement the non-stop mode remote protocol extensions, as
1122 described in the "Remote Non-Stop" section of the user manual. The
1123 GDB remote stub, gdbserver, has been adjusted to support these
1124 extensions on linux targets.
1126 * New commands (for set/show, see "New options" below)
1128 catch syscall [NAME(S) | NUMBER(S)]
1129 Catch system calls. Arguments, which should be names of system
1130 calls or their numbers, mean catch only those syscalls. Without
1131 arguments, every syscall will be caught. When the inferior issues
1132 any of the specified syscalls, GDB will stop and announce the system
1133 call, both when it is called and when its call returns. This
1134 feature is currently available with a native GDB running on the
1135 Linux Kernel, under the following architectures: x86, x86_64,
1136 PowerPC and PowerPC64.
1138 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1140 Search memory for a sequence of bytes.
1142 maint set python print-stack
1143 maint show python print-stack
1144 Show a stack trace when an error is encountered in a Python script.
1147 Invoke CODE by passing it to the Python interpreter.
1152 These allow macros to be defined, undefined, and listed
1156 Show operating system information about processes.
1159 List the inferiors currently under GDB's control.
1162 Switch focus to inferior number NUM.
1165 Detach from inferior number NUM.
1168 Kill inferior number NUM.
1172 set spu stop-on-load
1173 show spu stop-on-load
1174 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1176 set spu auto-flush-cache
1177 show spu auto-flush-cache
1178 Control whether to automatically flush the software-managed cache
1179 during Cell/B.E. debugging.
1181 set sh calling-convention
1182 show sh calling-convention
1183 Control the calling convention used when calling SH target functions.
1186 show debug timestamp
1187 Control display of timestamps with GDB debugging output.
1189 set disassemble-next-line
1190 show disassemble-next-line
1191 Control display of disassembled source lines or instructions when
1194 set remote noack-packet
1195 show remote noack-packet
1196 Set/show the use of remote protocol QStartNoAckMode packet. See above
1197 under "New remote packets."
1199 set remote query-attached-packet
1200 show remote query-attached-packet
1201 Control use of remote protocol `qAttached' (query-attached) packet.
1203 set remote read-siginfo-object
1204 show remote read-siginfo-object
1205 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1208 set remote write-siginfo-object
1209 show remote write-siginfo-object
1210 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1213 set remote reverse-continue
1214 show remote reverse-continue
1215 Control use of remote protocol 'bc' (reverse-continue) packet.
1217 set remote reverse-step
1218 show remote reverse-step
1219 Control use of remote protocol 'bs' (reverse-step) packet.
1221 set displaced-stepping
1222 show displaced-stepping
1223 Control displaced stepping mode. Displaced stepping is a way to
1224 single-step over breakpoints without removing them from the debuggee.
1225 Also known as "out-of-line single-stepping".
1228 show debug displaced
1229 Control display of debugging info for displaced stepping.
1231 maint set internal-error
1232 maint show internal-error
1233 Control what GDB does when an internal error is detected.
1235 maint set internal-warning
1236 maint show internal-warning
1237 Control what GDB does when an internal warning is detected.
1242 Use a wrapper program to launch programs for debugging.
1244 set multiple-symbols (all|ask|cancel)
1245 show multiple-symbols
1246 The value of this variable can be changed to adjust the debugger behavior
1247 when an expression or a breakpoint location contains an ambiguous symbol
1248 name (an overloaded function name, for instance).
1250 set breakpoint always-inserted
1251 show breakpoint always-inserted
1252 Keep breakpoints always inserted in the target, as opposed to inserting
1253 them when resuming the target, and removing them when the target stops.
1254 This option can improve debugger performance on slow remote targets.
1256 set arm fallback-mode (arm|thumb|auto)
1257 show arm fallback-mode
1258 set arm force-mode (arm|thumb|auto)
1260 These commands control how ARM GDB determines whether instructions
1261 are ARM or Thumb. The default for both settings is auto, which uses
1262 the current CPSR value for instructions without symbols; previous
1263 versions of GDB behaved as if "set arm fallback-mode arm".
1265 set disable-randomization
1266 show disable-randomization
1267 Standalone programs run with the virtual address space randomization enabled
1268 by default on some platforms. This option keeps the addresses stable across
1269 multiple debugging sessions.
1273 Control whether other threads are stopped or not when some thread hits
1278 Requests that asynchronous execution is enabled in the target, if available.
1279 In this case, it's possible to resume target in the background, and interact
1280 with GDB while the target is running. "show target-async" displays the
1281 current state of asynchronous execution of the target.
1283 set target-wide-charset
1284 show target-wide-charset
1285 The target-wide-charset is the name of the character set that GDB
1286 uses when printing characters whose type is wchar_t.
1288 set tcp auto-retry (on|off)
1290 set tcp connect-timeout
1291 show tcp connect-timeout
1292 These commands allow GDB to retry failed TCP connections to a remote stub
1293 with a specified timeout period; this is useful if the stub is launched
1294 in parallel with GDB but may not be ready to accept connections immediately.
1296 set libthread-db-search-path
1297 show libthread-db-search-path
1298 Control list of directories which GDB will search for appropriate
1301 set schedule-multiple (on|off)
1302 show schedule-multiple
1303 Allow GDB to resume all threads of all processes or only threads of
1304 the current process.
1308 Use more aggressive caching for accesses to the stack. This improves
1309 performance of remote debugging (particularly backtraces) without
1310 affecting correctness.
1312 set interactive-mode (on|off|auto)
1313 show interactive-mode
1314 Control whether GDB runs in interactive mode (on) or not (off).
1315 When in interactive mode, GDB waits for the user to answer all
1316 queries. Otherwise, GDB does not wait and assumes the default
1317 answer. When set to auto (the default), GDB determines which
1318 mode to use based on the stdin settings.
1323 For program forks, this is replaced by the new more generic `info
1324 inferiors' command. To list checkpoints, you can still use the
1325 `info checkpoints' command, which was an alias for the `info forks'
1329 Replaced by the new `inferior' command. To switch between
1330 checkpoints, you can still use the `restart' command, which was an
1331 alias for the `fork' command.
1334 This is removed, since some targets don't have a notion of
1335 processes. To switch between processes, you can still use the
1336 `inferior' command using GDB's own inferior number.
1339 For program forks, this is replaced by the new more generic `kill
1340 inferior' command. To delete a checkpoint, you can still use the
1341 `delete checkpoint' command, which was an alias for the `delete
1345 For program forks, this is replaced by the new more generic `detach
1346 inferior' command. To detach a checkpoint, you can still use the
1347 `detach checkpoint' command, which was an alias for the `detach
1350 * New native configurations
1352 x86/x86_64 Darwin i[34567]86-*-darwin*
1354 x86_64 MinGW x86_64-*-mingw*
1358 Lattice Mico32 lm32-*
1359 x86 DICOS i[34567]86-*-dicos*
1360 x86_64 DICOS x86_64-*-dicos*
1363 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1364 (mingw32ce) debugging.
1370 These commands were actually not implemented on any target.
1372 *** Changes in GDB 6.8
1374 * New native configurations
1376 NetBSD/hppa hppa*-*netbsd*
1377 Xtensa GNU/Linux xtensa*-*-linux*
1381 NetBSD/hppa hppa*-*-netbsd*
1382 Xtensa GNU/Lunux xtensa*-*-linux*
1384 * Change in command line behavior -- corefiles vs. process ids.
1386 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1387 attaching to process NUMBER fails, GDB no longer attempts to open a
1388 core file named NUMBER. Attaching to a program using the -c option
1389 is no longer supported. Instead, use the '-p' or '--pid' options.
1391 * GDB can now be built as a native debugger for debugging Windows x86
1392 (mingw32) Portable Executable (PE) programs.
1394 * Pending breakpoints no longer change their number when their address
1397 * GDB now supports breakpoints with multiple locations,
1398 including breakpoints on C++ constructors, inside C++ templates,
1399 and in inlined functions.
1401 * GDB's ability to debug optimized code has been improved. GDB more
1402 accurately identifies function bodies and lexical blocks that occupy
1403 more than one contiguous range of addresses.
1405 * Target descriptions can now describe registers for PowerPC.
1407 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1408 registers on PowerPC targets.
1410 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1411 targets even when the libthread_db library is not available.
1413 * The GDB remote stub, gdbserver, now supports the new file transfer
1414 commands (remote put, remote get, and remote delete).
1416 * The GDB remote stub, gdbserver, now supports run and attach in
1417 extended-remote mode.
1419 * hppa*64*-*-hpux11* target broken
1420 The debugger is unable to start a program and fails with the following
1421 error: "Error trying to get information about dynamic linker".
1422 The gdb-6.7 release is also affected.
1424 * GDB now supports the --enable-targets= configure option to allow
1425 building a single GDB executable that supports multiple remote
1426 target architectures.
1428 * GDB now supports debugging C and C++ programs which use the
1429 Decimal Floating Point extension. In addition, the PowerPC target
1430 now has a set of pseudo-registers to inspect decimal float values
1431 stored in two consecutive float registers.
1433 * The -break-insert MI command can optionally create pending
1436 * Improved support for debugging Ada
1437 Many improvements to the Ada language support have been made. These
1439 - Better support for Ada2005 interface types
1440 - Improved handling of arrays and slices in general
1441 - Better support for Taft-amendment types
1442 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1444 - Improved command completion in Ada
1447 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1452 set print frame-arguments (all|scalars|none)
1453 show print frame-arguments
1454 The value of this variable can be changed to control which argument
1455 values should be printed by the debugger when displaying a frame.
1460 Transfer files to and from a remote target, and delete remote files.
1467 Transfer files to and from a remote target, and delete remote files.
1469 * New remote packets
1476 Open, close, read, write, and delete files on the remote system.
1479 Attach to an existing process on the remote system, in extended-remote
1483 Run a new process on the remote system, in extended-remote mode.
1485 *** Changes in GDB 6.7
1487 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1488 bfd, libiberty and opcodes, as revealed by static analysis donated by
1489 Coverity, Inc. (http://scan.coverity.com).
1491 * When looking up multiply-defined global symbols, GDB will now prefer the
1492 symbol definition in the current shared library if it was built using the
1493 -Bsymbolic linker option.
1495 * When the Text User Interface (TUI) is not configured, GDB will now
1496 recognize the -tui command-line option and print a message that the TUI
1499 * The GDB remote stub, gdbserver, now has lower overhead for high
1500 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1502 * GDB for MIPS targets now autodetects whether a remote target provides
1503 32-bit or 64-bit register values.
1505 * Support for C++ member pointers has been improved.
1507 * GDB now understands XML target descriptions, which specify the
1508 target's overall architecture. GDB can read a description from
1509 a local file or over the remote serial protocol.
1511 * Vectors of single-byte data use a new integer type which is not
1512 automatically displayed as character or string data.
1514 * The /s format now works with the print command. It displays
1515 arrays of single-byte integers and pointers to single-byte integers
1518 * Target descriptions can now describe target-specific registers,
1519 for architectures which have implemented the support (currently
1520 only ARM, M68K, and MIPS).
1522 * GDB and the GDB remote stub, gdbserver, now support the XScale
1525 * The GDB remote stub, gdbserver, has been updated to support
1526 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1527 has been rewritten to use the standard GDB remote protocol.
1529 * GDB can now step into C++ functions which are called through thunks.
1531 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1533 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1534 layout. It also supports a TextSeg= and DataSeg= response when only
1535 segment base addresses (rather than offsets) are available.
1537 * The /i format now outputs any trailing branch delay slot instructions
1538 immediately following the last instruction within the count specified.
1540 * The GDB remote protocol "T" stop reply packet now supports a
1541 "library" response. Combined with the new "qXfer:libraries:read"
1542 packet, this response allows GDB to debug shared libraries on targets
1543 where the operating system manages the list of loaded libraries (e.g.
1544 Windows and SymbianOS).
1546 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1547 (DLLs) on Windows and Windows CE targets.
1549 * GDB now supports a faster verification that a .debug file matches its binary
1550 according to its build-id signature, if the signature is present.
1556 Enable or disable hardware flow control (RTS/CTS) on the serial port
1557 when debugging using remote targets.
1559 set mem inaccessible-by-default
1560 show mem inaccessible-by-default
1561 If the target supplies a memory map, for instance via the remote
1562 protocol's "qXfer:memory-map:read" packet, setting this variable
1563 prevents GDB from accessing memory outside the memory map. This
1564 is useful for targets with memory mapped registers or which react
1565 badly to accesses of unmapped address space.
1567 set breakpoint auto-hw
1568 show breakpoint auto-hw
1569 If the target supplies a memory map, for instance via the remote
1570 protocol's "qXfer:memory-map:read" packet, setting this variable
1571 lets GDB use hardware breakpoints automatically for memory regions
1572 where it can not use software breakpoints. This covers both the
1573 "break" command and internal breakpoints used for other commands
1574 including "next" and "finish".
1577 catch exception unhandled
1578 Stop the program execution when Ada exceptions are raised.
1581 Stop the program execution when an Ada assertion failed.
1585 Set an alternate system root for target files. This is a more
1586 general version of "set solib-absolute-prefix", which is now
1587 an alias to "set sysroot".
1590 Provide extended SPU facility status information. This set of
1591 commands is available only when debugging the Cell/B.E. SPU
1594 * New native configurations
1596 OpenBSD/sh sh*-*openbsd*
1599 unset tdesc filename
1601 Use the specified local file as an XML target description, and do
1602 not query the target for its built-in description.
1606 OpenBSD/sh sh*-*-openbsd*
1607 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1608 Toshiba Media Processor mep-elf
1610 * New remote packets
1613 Ignore the specified signals; pass them directly to the debugged program
1614 without stopping other threads or reporting them to GDB.
1616 qXfer:features:read:
1617 Read an XML target description from the target, which describes its
1622 Read or write contents of an spufs file on the target system. These
1623 packets are available only on the Cell/B.E. SPU architecture.
1625 qXfer:libraries:read:
1626 Report the loaded shared libraries. Combined with new "T" packet
1627 response, this packet allows GDB to debug shared libraries on
1628 targets where the operating system manages the list of loaded
1629 libraries (e.g. Windows and SymbianOS).
1633 Support for these obsolete configurations has been removed.
1641 i[34567]86-*-lynxos*
1642 i[34567]86-*-netware*
1643 i[34567]86-*-sco3.2v5*
1644 i[34567]86-*-sco3.2v4*
1646 i[34567]86-*-sysv4.2*
1649 i[34567]86-*-unixware2*
1650 i[34567]86-*-unixware*
1659 * Other removed features
1666 Various m68k-only ROM monitors.
1673 Various Renesas ROM monitors and debugging interfaces for SH and
1678 Support for a Macraigor serial interface to on-chip debugging.
1679 GDB does not directly support the newer parallel or USB
1684 A debug information format. The predecessor to DWARF 2 and
1685 DWARF 3, which are still supported.
1687 Support for the HP aCC compiler on HP-UX/PA-RISC
1689 SOM-encapsulated symbolic debugging information, automatic
1690 invocation of pxdb, and the aCC custom C++ ABI. This does not
1691 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1692 with aCC can still be debugged on an assembly level.
1694 MIPS ".pdr" sections
1696 A MIPS-specific format used to describe stack frame layout
1697 in debugging information.
1701 GDB could work with an older version of Guile to debug
1702 the interpreter and Scheme programs running in it.
1704 set mips stack-arg-size
1705 set mips saved-gpreg-size
1707 Use "set mips abi" to control parameter passing for MIPS.
1709 *** Changes in GDB 6.6
1714 Cell Broadband Engine SPU spu-elf
1716 * GDB can now be configured as a cross-debugger targeting native Windows
1717 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1718 running on a Windows system over TCP/IP to debug Windows programs.
1720 * The GDB remote stub, gdbserver, has been updated to support Windows and
1721 Cygwin debugging. Both single-threaded and multi-threaded programs are
1724 * The "set trust-readonly-sections" command works again. This command was
1725 broken in GDB 6.3, 6.4, and 6.5.
1727 * The "load" command now supports writing to flash memory, if the remote
1728 stub provides the required support.
1730 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1731 longer requires symbolic debug information (e.g. DWARF-2).
1736 unset substitute-path
1737 show substitute-path
1738 Manage a list of substitution rules that GDB uses to rewrite the name
1739 of the directories where the sources are located. This can be useful
1740 for instance when the sources were moved to a different location
1741 between compilation and debugging.
1745 Print each CLI command as it is executed. Each command is prefixed with
1746 a number of `+' symbols representing the nesting depth.
1747 The source command now has a `-v' option to enable the same feature.
1751 The ARM Demon monitor support (RDP protocol, "target rdp").
1753 Kernel Object Display, an embedded debugging feature which only worked with
1754 an obsolete version of Cisco IOS.
1756 The 'set download-write-size' and 'show download-write-size' commands.
1758 * New remote packets
1761 Tell a stub about GDB client features, and request remote target features.
1762 The first feature implemented is PacketSize, which allows the target to
1763 specify the size of packets it can handle - to minimize the number of
1764 packets required and improve performance when connected to a remote
1768 Fetch an OS auxilliary vector from the remote stub. This packet is a
1769 more efficient replacement for qPart:auxv:read.
1771 qXfer:memory-map:read:
1772 Fetch a memory map from the remote stub, including information about
1773 RAM, ROM, and flash memory devices.
1778 Erase and program a flash memory device.
1780 * Removed remote packets
1783 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1784 used it, and only gdbserver implemented it.
1786 *** Changes in GDB 6.5
1790 Renesas M32C/M16C m32c-elf
1792 Morpho Technologies ms1 ms1-elf
1796 init-if-undefined Initialize a convenience variable, but
1797 only if it doesn't already have a value.
1799 The following commands are presently only implemented for native GNU/Linux:
1801 checkpoint Save a snapshot of the program state.
1803 restart <n> Return the program state to a
1804 previously saved state.
1806 info checkpoints List currently saved checkpoints.
1808 delete-checkpoint <n> Delete a previously saved checkpoint.
1810 set|show detach-on-fork Tell gdb whether to detach from a newly
1811 forked process, or to keep debugging it.
1813 info forks List forks of the user program that
1814 are available to be debugged.
1816 fork <n> Switch to debugging one of several
1817 forks of the user program that are
1818 available to be debugged.
1820 delete-fork <n> Delete a fork from the list of forks
1821 that are available to be debugged (and
1822 kill the forked process).
1824 detach-fork <n> Delete a fork from the list of forks
1825 that are available to be debugged (and
1826 allow the process to continue).
1830 Morpho Technologies ms2 ms1-elf
1832 * Improved Windows host support
1834 GDB now builds as a cross debugger hosted on i686-mingw32, including
1835 native console support, and remote communications using either
1836 network sockets or serial ports.
1838 * Improved Modula-2 language support
1840 GDB can now print most types in the Modula-2 syntax. This includes:
1841 basic types, set types, record types, enumerated types, range types,
1842 pointer types and ARRAY types. Procedure var parameters are correctly
1843 printed and hexadecimal addresses and character constants are also
1844 written in the Modula-2 syntax. Best results can be obtained by using
1845 GNU Modula-2 together with the -gdwarf-2 command line option.
1849 The ARM rdi-share module.
1851 The Netware NLM debug server.
1853 *** Changes in GDB 6.4
1855 * New native configurations
1857 OpenBSD/arm arm*-*-openbsd*
1858 OpenBSD/mips64 mips64-*-openbsd*
1862 Morpho Technologies ms1 ms1-elf
1864 * New command line options
1866 --batch-silent As for --batch, but totally silent.
1867 --return-child-result The debugger will exist with the same value
1868 the child (debugged) program exited with.
1869 --eval-command COMMAND, -ex COMMAND
1870 Execute a single GDB CLI command. This may be
1871 specified multiple times and in conjunction
1872 with the --command (-x) option.
1874 * Deprecated commands removed
1876 The following commands, that were deprecated in 2000, have been
1880 set|show arm disassembly-flavor set|show arm disassembler
1881 othernames set arm disassembler
1882 set|show remotedebug set|show debug remote
1883 set|show archdebug set|show debug arch
1884 set|show eventdebug set|show debug event
1887 * New BSD user-level threads support
1889 It is now possible to debug programs using the user-level threads
1890 library on OpenBSD and FreeBSD. Currently supported (target)
1893 FreeBSD/amd64 x86_64-*-freebsd*
1894 FreeBSD/i386 i386-*-freebsd*
1895 OpenBSD/i386 i386-*-openbsd*
1897 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1898 are not yet supported.
1900 * New support for Matsushita MN10300 w/sim added
1901 (Work in progress). mn10300-elf.
1903 * REMOVED configurations and files
1905 VxWorks and the XDR protocol *-*-vxworks
1906 Motorola MCORE mcore-*-*
1907 National Semiconductor NS32000 ns32k-*-*
1909 * New "set print array-indexes" command
1911 After turning this setting "on", GDB prints the index of each element
1912 when displaying arrays. The default is "off" to preserve the previous
1915 * VAX floating point support
1917 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1919 * User-defined command support
1921 In addition to using $arg0..$arg9 for argument passing, it is now possible
1922 to use $argc to determine now many arguments have been passed. See the
1923 section on user-defined commands in the user manual for more information.
1925 *** Changes in GDB 6.3:
1927 * New command line option
1929 GDB now accepts -l followed by a number to set the timeout for remote
1932 * GDB works with GCC -feliminate-dwarf2-dups
1934 GDB now supports a more compact representation of DWARF-2 debug
1935 information using DW_FORM_ref_addr references. These are produced
1936 by GCC with the option -feliminate-dwarf2-dups and also by some
1937 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1938 to use -feliminate-dwarf2-dups.
1940 * Internationalization
1942 When supported by the host system, GDB will be built with
1943 internationalization (libintl). The task of marking up the sources is
1944 continued, we're looking forward to our first translation.
1948 Initial support for debugging programs compiled with the GNAT
1949 implementation of the Ada programming language has been integrated
1950 into GDB. In this release, support is limited to expression evaluation.
1952 * New native configurations
1954 GNU/Linux/m32r m32r-*-linux-gnu
1958 GDB's remote protocol now includes support for the 'p' packet. This
1959 packet is used to fetch individual registers from a remote inferior.
1961 * END-OF-LIFE registers[] compatibility module
1963 GDB's internal register infrastructure has been completely rewritten.
1964 The new infrastructure making possible the implementation of key new
1965 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1968 GDB 6.3 will be the last release to include the the registers[]
1969 compatibility module that allowed out-of-date configurations to
1970 continue to work. This change directly impacts the following
1980 powerpc bdm protocol
1982 Unless there is activity to revive these configurations, they will be
1983 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1985 * OBSOLETE configurations and files
1987 Configurations that have been declared obsolete in this release have
1988 been commented out. Unless there is activity to revive these
1989 configurations, the next release of GDB will have their sources
1990 permanently REMOVED.
1999 *** Changes in GDB 6.2.1:
2001 * MIPS `break main; run' gave an heuristic-fence-post warning
2003 When attempting to run even a simple program, a warning about
2004 heuristic-fence-post being hit would be reported. This problem has
2007 * MIPS IRIX 'long double' crashed GDB
2009 When examining a long double variable, GDB would get a segmentation
2010 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2011 IRIX long double values).
2015 A bug in the VAX stack code was causing problems with the "next"
2016 command. This problem has been fixed.
2018 *** Changes in GDB 6.2:
2020 * Fix for ``many threads''
2022 On GNU/Linux systems that use the NPTL threads library, a program
2023 rapidly creating and deleting threads would confuse GDB leading to the
2026 ptrace: No such process.
2027 thread_db_get_info: cannot get thread info: generic error
2029 This problem has been fixed.
2031 * "-async" and "-noasync" options removed.
2033 Support for the broken "-noasync" option has been removed (it caused
2036 * New ``start'' command.
2038 This command runs the program until the begining of the main procedure.
2040 * New BSD Kernel Data Access Library (libkvm) interface
2042 Using ``target kvm'' it is now possible to debug kernel core dumps and
2043 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2044 platforms. Currently supported (native-only) configurations are:
2046 FreeBSD/amd64 x86_64-*-freebsd*
2047 FreeBSD/i386 i?86-*-freebsd*
2048 NetBSD/i386 i?86-*-netbsd*
2049 NetBSD/m68k m68*-*-netbsd*
2050 NetBSD/sparc sparc-*-netbsd*
2051 OpenBSD/amd64 x86_64-*-openbsd*
2052 OpenBSD/i386 i?86-*-openbsd*
2053 OpenBSD/m68k m68*-openbsd*
2054 OpenBSD/sparc sparc-*-openbsd*
2056 * Signal trampoline code overhauled
2058 Many generic problems with GDB's signal handling code have been fixed.
2059 These include: backtraces through non-contiguous stacks; recognition
2060 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2061 call; backtrace through a signal trampoline; step into and out of
2062 signal handlers; and single-stepping in the signal trampoline.
2064 Please note that kernel bugs are a limiting factor here. These
2065 features have been shown to work on an s390 GNU/Linux system that
2066 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2068 * Cygwin support for DWARF 2 added.
2070 * New native configurations
2072 GNU/Linux/hppa hppa*-*-linux*
2073 OpenBSD/hppa hppa*-*-openbsd*
2074 OpenBSD/m68k m68*-*-openbsd*
2075 OpenBSD/m88k m88*-*-openbsd*
2076 OpenBSD/powerpc powerpc-*-openbsd*
2077 NetBSD/vax vax-*-netbsd*
2078 OpenBSD/vax vax-*-openbsd*
2080 * END-OF-LIFE frame compatibility module
2082 GDB's internal frame infrastructure has been completely rewritten.
2083 The new infrastructure making it possible to support key new features
2084 including DWARF 2 Call Frame Information. To aid in the task of
2085 migrating old configurations to this new infrastructure, a
2086 compatibility module, that allowed old configurations to continue to
2087 work, was also included.
2089 GDB 6.2 will be the last release to include this frame compatibility
2090 module. This change directly impacts the following configurations:
2100 Unless there is activity to revive these configurations, they will be
2101 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2103 * REMOVED configurations and files
2105 Sun 3, running SunOS 3 m68*-*-sunos3*
2106 Sun 3, running SunOS 4 m68*-*-sunos4*
2107 Sun 2, running SunOS 3 m68000-*-sunos3*
2108 Sun 2, running SunOS 4 m68000-*-sunos4*
2109 Motorola 680x0 running LynxOS m68*-*-lynxos*
2110 AT&T 3b1/Unix pc m68*-att-*
2111 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2112 decstation mips-dec-* mips-little-*
2113 riscos mips-*-riscos* mips-*-sysv*
2114 sonymips mips-sony-*
2115 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2117 *** Changes in GDB 6.1.1:
2119 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2121 The TUI (Text-mode User Interface) is now built as part of a default
2122 GDB configuration. It is enabled by either selecting the TUI with the
2123 command line option "-i=tui" or by running the separate "gdbtui"
2124 program. For more information on the TUI, see the manual "Debugging
2127 * Pending breakpoint support (also included in GDB 6.1)
2129 Support has been added to allow you to specify breakpoints in shared
2130 libraries that have not yet been loaded. If a breakpoint location
2131 cannot be found, and the "breakpoint pending" option is set to auto,
2132 GDB queries you if you wish to make the breakpoint pending on a future
2133 shared-library load. If and when GDB resolves the breakpoint symbol,
2134 the pending breakpoint is removed as one or more regular breakpoints
2137 Pending breakpoints are very useful for GCJ Java debugging.
2139 * Fixed ISO-C build problems
2141 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2142 non ISO-C code that stopped them being built using a more strict ISO-C
2143 compiler (e.g., IBM's C compiler).
2145 * Fixed build problem on IRIX 5
2147 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2148 wasn't able to compile compile on an IRIX 5 system.
2150 * Added execute permission to gdb/gdbserver/configure
2152 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2153 permission. This bug would cause configure to fail on a number of
2154 systems (Solaris, IRIX). Ref: server/519.
2156 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2158 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2159 has been updated to use constant array sizes.
2161 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2163 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2164 its generated DWARF Call Frame Info. This encoding was causing GDB to
2165 panic, that panic has been fixed. Ref: gdb/1628.
2167 * Fixed a problem when examining parameters in shared library code.
2169 When examining parameters in optimized shared library code generated
2170 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2171 not available''. GDB now correctly displays the variable's value.
2173 *** Changes in GDB 6.1:
2175 * Removed --with-mmalloc
2177 Support for the mmalloc memory manager has been removed, as it
2178 conflicted with the internal gdb byte cache.
2180 * Changes in AMD64 configurations
2182 The AMD64 target now includes the %cs and %ss registers. As a result
2183 the AMD64 remote protocol has changed; this affects the floating-point
2184 and SSE registers. If you rely on those registers for your debugging,
2185 you should upgrade gdbserver on the remote side.
2187 * Revised SPARC target
2189 The SPARC target has been completely revised, incorporating the
2190 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2191 support for LynxOS and SunOS 4 has been dropped. Calling functions
2192 from within GDB on operating systems with a non-executable stack
2193 (Solaris, OpenBSD) now works.
2197 GDB has a new C++ demangler which does a better job on the mangled
2198 names generated by current versions of g++. It also runs faster, so
2199 with this and other changes gdb should now start faster on large C++
2202 * DWARF 2 Location Expressions
2204 GDB support for location expressions has been extended to support function
2205 arguments and frame bases. Older versions of GDB could crash when they
2208 * C++ nested types and namespaces
2210 GDB's support for nested types and namespaces in C++ has been
2211 improved, especially if you use the DWARF 2 debugging format. (This
2212 is the default for recent versions of GCC on most platforms.)
2213 Specifically, if you have a class "Inner" defined within a class or
2214 namespace "Outer", then GDB realizes that the class's name is
2215 "Outer::Inner", not simply "Inner". This should greatly reduce the
2216 frequency of complaints about not finding RTTI symbols. In addition,
2217 if you are stopped at inside of a function defined within a namespace,
2218 GDB modifies its name lookup accordingly.
2220 * New native configurations
2222 NetBSD/amd64 x86_64-*-netbsd*
2223 OpenBSD/amd64 x86_64-*-openbsd*
2224 OpenBSD/alpha alpha*-*-openbsd*
2225 OpenBSD/sparc sparc-*-openbsd*
2226 OpenBSD/sparc64 sparc64-*-openbsd*
2228 * New debugging protocols
2230 M32R with SDI protocol m32r-*-elf*
2232 * "set prompt-escape-char" command deleted.
2234 The command "set prompt-escape-char" has been deleted. This command,
2235 and its very obscure effet on GDB's prompt, was never documented,
2236 tested, nor mentioned in the NEWS file.
2238 * OBSOLETE configurations and files
2240 Configurations that have been declared obsolete in this release have
2241 been commented out. Unless there is activity to revive these
2242 configurations, the next release of GDB will have their sources
2243 permanently REMOVED.
2245 Sun 3, running SunOS 3 m68*-*-sunos3*
2246 Sun 3, running SunOS 4 m68*-*-sunos4*
2247 Sun 2, running SunOS 3 m68000-*-sunos3*
2248 Sun 2, running SunOS 4 m68000-*-sunos4*
2249 Motorola 680x0 running LynxOS m68*-*-lynxos*
2250 AT&T 3b1/Unix pc m68*-att-*
2251 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2252 decstation mips-dec-* mips-little-*
2253 riscos mips-*-riscos* mips-*-sysv*
2254 sonymips mips-sony-*
2255 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2257 * REMOVED configurations and files
2259 SGI Irix-4.x mips-sgi-irix4 or iris4
2260 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2261 Z8000 simulator z8k-zilog-none or z8ksim
2262 Matsushita MN10200 w/simulator mn10200-*-*
2263 H8/500 simulator h8500-hitachi-hms or h8500hms
2264 HP/PA running BSD hppa*-*-bsd*
2265 HP/PA running OSF/1 hppa*-*-osf*
2266 HP/PA Pro target hppa*-*-pro*
2267 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2268 386BSD i[3456]86-*-bsd*
2269 Sequent family i[3456]86-sequent-sysv4*
2270 i[3456]86-sequent-sysv*
2271 i[3456]86-sequent-bsd*
2272 SPARC running LynxOS sparc-*-lynxos*
2273 SPARC running SunOS 4 sparc-*-sunos4*
2274 Tsqware Sparclet sparclet-*-*
2275 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2277 *** Changes in GDB 6.0:
2281 Support for debugging the Objective-C programming language has been
2282 integrated into GDB.
2284 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2286 DWARF 2's Call Frame Information makes available compiler generated
2287 information that more exactly describes the program's run-time stack.
2288 By using this information, GDB is able to provide more robust stack
2291 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2292 have been updated to use a new backtrace mechanism which includes
2293 DWARF 2 CFI support.
2297 GDB's remote protocol has been extended to include support for hosted
2298 file I/O (where the remote target uses GDB's file system). See GDB's
2299 remote protocol documentation for details.
2301 * All targets using the new architecture framework.
2303 All of GDB's targets have been updated to use the new internal
2304 architecture framework. The way is now open for future GDB releases
2305 to include cross-architecture native debugging support (i386 on amd64,
2308 * GNU/Linux's Thread Local Storage (TLS)
2310 GDB now includes support for for the GNU/Linux implementation of
2311 per-thread variables.
2313 * GNU/Linux's Native POSIX Thread Library (NPTL)
2315 GDB's thread code has been updated to work with either the new
2316 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2318 * Separate debug info.
2320 GDB, in conjunction with BINUTILS, now supports a mechanism for
2321 automatically loading debug information from a separate file. Instead
2322 of shipping full debug and non-debug versions of system libraries,
2323 system integrators can now instead ship just the stripped libraries
2324 and optional debug files.
2326 * DWARF 2 Location Expressions
2328 DWARF 2 Location Expressions allow the compiler to more completely
2329 describe the location of variables (even in optimized code) to the
2332 GDB now includes preliminary support for location expressions (support
2333 for DW_OP_piece is still missing).
2337 A number of long standing bugs that caused GDB to die while starting a
2338 Java application have been fixed. GDB's Java support is now
2339 considered "useable".
2341 * GNU/Linux support for fork, vfork, and exec.
2343 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2344 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2347 * GDB supports logging output to a file
2349 There are two new commands, "set logging" and "show logging", which can be
2350 used to capture GDB's output to a file.
2352 * The meaning of "detach" has changed for gdbserver
2354 The "detach" command will now resume the application, as documented. To
2355 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2358 * d10v, m68hc11 `regs' command deprecated
2360 The `info registers' command has been updated so that it displays the
2361 registers using a format identical to the old `regs' command.
2365 A new command, "maint set profile on/off", has been added. This command can
2366 be used to enable or disable profiling while running GDB, to profile a
2367 session or a set of commands. In addition there is a new configure switch,
2368 "--enable-profiling", which will cause GDB to be compiled with profiling
2369 data, for more informative profiling results.
2371 * Default MI syntax changed to "mi2".
2373 The default MI (machine interface) syntax, enabled by the command line
2374 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2375 "mi1", can be enabled by specifying the option "-i=mi1".
2377 Support for the original "mi0" syntax (included in GDB 5.0) has been
2380 Fix for gdb/192: removed extraneous space when displaying frame level.
2381 Fix for gdb/672: update changelist is now output in mi list format.
2382 Fix for gdb/702: a -var-assign that updates the value now shows up
2383 in a subsequent -var-update.
2385 * New native configurations.
2387 FreeBSD/amd64 x86_64-*-freebsd*
2389 * Multi-arched targets.
2391 HP/PA HPUX11 hppa*-*-hpux*
2392 Renesas M32R/D w/simulator m32r-*-elf*
2394 * OBSOLETE configurations and files
2396 Configurations that have been declared obsolete in this release have
2397 been commented out. Unless there is activity to revive these
2398 configurations, the next release of GDB will have their sources
2399 permanently REMOVED.
2401 Z8000 simulator z8k-zilog-none or z8ksim
2402 Matsushita MN10200 w/simulator mn10200-*-*
2403 H8/500 simulator h8500-hitachi-hms or h8500hms
2404 HP/PA running BSD hppa*-*-bsd*
2405 HP/PA running OSF/1 hppa*-*-osf*
2406 HP/PA Pro target hppa*-*-pro*
2407 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2408 Sequent family i[3456]86-sequent-sysv4*
2409 i[3456]86-sequent-sysv*
2410 i[3456]86-sequent-bsd*
2411 Tsqware Sparclet sparclet-*-*
2412 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2414 * REMOVED configurations and files
2417 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2418 IBM AIX PS/2 i[3456]86-*-aix
2419 i386 running Mach 3.0 i[3456]86-*-mach3*
2420 i386 running Mach i[3456]86-*-mach*
2421 i386 running OSF/1 i[3456]86-*osf1mk*
2422 HP/Apollo 68k Family m68*-apollo*-sysv*,
2424 m68*-hp-bsd*, m68*-hp-hpux*
2425 Argonaut Risc Chip (ARC) arc-*-*
2426 Mitsubishi D30V d30v-*-*
2427 Fujitsu FR30 fr30-*-elf*
2428 OS/9000 i[34]86-*-os9k
2429 I960 with MON960 i960-*-coff
2431 * MIPS $fp behavior changed
2433 The convenience variable $fp, for the MIPS, now consistently returns
2434 the address of the current frame's base. Previously, depending on the
2435 context, $fp could refer to either $sp or the current frame's base
2436 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2437 The GNU Source-Level Debugger''.
2439 *** Changes in GDB 5.3:
2441 * GNU/Linux shared library multi-threaded performance improved.
2443 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2444 `/proc', in preference to `ptrace' for memory reads. This may result
2445 in an improvement in the start-up time of multi-threaded, shared
2446 library applications when run under GDB. One GDB user writes: ``loads
2447 shared libs like mad''.
2449 * ``gdbserver'' now supports multi-threaded applications on some targets
2451 Support for debugging multi-threaded applications which use
2452 the GNU/Linux LinuxThreads package has been added for
2453 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2454 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2456 * GDB now supports C/C++ preprocessor macros.
2458 GDB now expands preprocessor macro invocations in C/C++ expressions,
2459 and provides various commands for showing macro definitions and how
2462 The new command `macro expand EXPRESSION' expands any macro
2463 invocations in expression, and shows the result.
2465 The new command `show macro MACRO-NAME' shows the definition of the
2466 macro named MACRO-NAME, and where it was defined.
2468 Most compilers don't include information about macros in the debugging
2469 information by default. In GCC 3.1, for example, you need to compile
2470 your program with the options `-gdwarf-2 -g3'. If the macro
2471 information is present in the executable, GDB will read it.
2473 * Multi-arched targets.
2475 DEC Alpha (partial) alpha*-*-*
2476 DEC VAX (partial) vax-*-*
2478 National Semiconductor NS32000 (partial) ns32k-*-*
2479 Motorola 68000 (partial) m68k-*-*
2480 Motorola MCORE mcore-*-*
2484 Fujitsu FRV architecture added by Red Hat frv*-*-*
2487 * New native configurations
2489 Alpha NetBSD alpha*-*-netbsd*
2490 SH NetBSD sh*-*-netbsdelf*
2491 MIPS NetBSD mips*-*-netbsd*
2492 UltraSPARC NetBSD sparc64-*-netbsd*
2494 * OBSOLETE configurations and files
2496 Configurations that have been declared obsolete in this release have
2497 been commented out. Unless there is activity to revive these
2498 configurations, the next release of GDB will have their sources
2499 permanently REMOVED.
2501 Mitsubishi D30V d30v-*-*
2502 OS/9000 i[34]86-*-os9k
2503 IBM AIX PS/2 i[3456]86-*-aix
2504 Fujitsu FR30 fr30-*-elf*
2505 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2506 Argonaut Risc Chip (ARC) arc-*-*
2507 i386 running Mach 3.0 i[3456]86-*-mach3*
2508 i386 running Mach i[3456]86-*-mach*
2509 i386 running OSF/1 i[3456]86-*osf1mk*
2510 HP/Apollo 68k Family m68*-apollo*-sysv*,
2512 m68*-hp-bsd*, m68*-hp-hpux*
2513 I960 with MON960 i960-*-coff
2515 * OBSOLETE languages
2517 CHILL, a Pascal like language used by telecommunications companies.
2519 * REMOVED configurations and files
2521 AMD 29k family via UDI a29k-amd-udi, udi29k
2522 A29K VxWorks a29k-*-vxworks
2523 AMD 29000 embedded, using EBMON a29k-none-none
2524 AMD 29000 embedded with COFF a29k-none-coff
2525 AMD 29000 embedded with a.out a29k-none-aout
2527 testsuite/gdb.hp/gdb.threads-hp/ directory
2529 * New command "set max-user-call-depth <nnn>"
2531 This command allows the user to limit the call depth of user-defined
2532 commands. The default is 1024.
2534 * Changes in FreeBSD/i386 native debugging.
2536 Support for the "generate-core-file" has been added.
2538 * New commands "dump", "append", and "restore".
2540 These commands allow data to be copied from target memory
2541 to a bfd-format or binary file (dump and append), and back
2542 from a file into memory (restore).
2544 * Improved "next/step" support on multi-processor Alpha Tru64.
2546 The previous single-step mechanism could cause unpredictable problems,
2547 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2548 of a software single-step mechanism prevents this.
2550 *** Changes in GDB 5.2.1:
2558 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2559 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2560 Fix, by Joel Brobecker imported from mainline.
2562 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2563 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2564 Fix, by Fred Fish, imported from mainline.
2566 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2567 Surprisingly enough, it works now.
2568 By Michal Ludvig, imported from mainline.
2570 i386 hardware watchpoint support:
2571 avoid misses on second run for some targets.
2572 By Pierre Muller, imported from mainline.
2574 *** Changes in GDB 5.2:
2576 * New command "set trust-readonly-sections on[off]".
2578 This command is a hint that tells gdb that read-only sections
2579 really are read-only (ie. that their contents will not change).
2580 In this mode, gdb will go to the object file rather than the
2581 target to read memory from read-only sections (such as ".text").
2582 This can be a significant performance improvement on some
2583 (notably embedded) targets.
2585 * New command "generate-core-file" (or "gcore").
2587 This new gdb command allows the user to drop a core file of the child
2588 process state at any time. So far it's been implemented only for
2589 GNU/Linux and Solaris, but should be relatively easily ported to other
2590 hosts. Argument is core file name (defaults to core.<pid>).
2592 * New command line option
2594 GDB now accepts --pid or -p followed by a process id.
2596 * Change in command line behavior -- corefiles vs. process ids.
2598 There is a subtle behavior in the way in which GDB handles
2599 command line arguments. The first non-flag argument is always
2600 a program to debug, but the second non-flag argument may either
2601 be a corefile or a process id. Previously, GDB would attempt to
2602 open the second argument as a corefile, and if that failed, would
2603 issue a superfluous error message and then attempt to attach it as
2604 a process. Now, if the second argument begins with a non-digit,
2605 it will be treated as a corefile. If it begins with a digit,
2606 GDB will attempt to attach it as a process, and if no such process
2607 is found, will then attempt to open it as a corefile.
2609 * Changes in ARM configurations.
2611 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2612 configuration is fully multi-arch.
2614 * New native configurations
2616 ARM NetBSD arm*-*-netbsd*
2617 x86 OpenBSD i[3456]86-*-openbsd*
2618 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2619 Sparc64 running FreeBSD sparc64-*-freebsd*
2623 Sanyo XStormy16 xstormy16-elf
2625 * OBSOLETE configurations and files
2627 Configurations that have been declared obsolete in this release have
2628 been commented out. Unless there is activity to revive these
2629 configurations, the next release of GDB will have their sources
2630 permanently REMOVED.
2632 AMD 29k family via UDI a29k-amd-udi, udi29k
2633 A29K VxWorks a29k-*-vxworks
2634 AMD 29000 embedded, using EBMON a29k-none-none
2635 AMD 29000 embedded with COFF a29k-none-coff
2636 AMD 29000 embedded with a.out a29k-none-aout
2638 testsuite/gdb.hp/gdb.threads-hp/ directory
2640 * REMOVED configurations and files
2642 TI TMS320C80 tic80-*-*
2644 PowerPC Solaris powerpcle-*-solaris*
2645 PowerPC Windows NT powerpcle-*-cygwin32
2646 PowerPC Netware powerpc-*-netware*
2647 Harris/CXUX m88k m88*-harris-cxux*
2648 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2649 ns32k-utek-sysv* ns32k-utek-*
2650 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2651 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2652 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2653 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2654 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2656 * Changes to command line processing
2658 The new `--args' feature can be used to specify command-line arguments
2659 for the inferior from gdb's command line.
2661 * Changes to key bindings
2663 There is a new `operate-and-get-next' function bound to `C-o'.
2665 *** Changes in GDB 5.1.1
2667 Fix compile problem on DJGPP.
2669 Fix a problem with floating-point registers on the i386 being
2672 Fix to stop GDB crashing on .debug_str debug info.
2674 Numerous documentation fixes.
2676 Numerous testsuite fixes.
2678 *** Changes in GDB 5.1:
2680 * New native configurations
2682 Alpha FreeBSD alpha*-*-freebsd*
2683 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2684 MIPS GNU/Linux mips*-*-linux*
2685 MIPS SGI Irix 6.x mips*-sgi-irix6*
2686 ia64 AIX ia64-*-aix*
2687 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2691 Motorola 68HC11 and 68HC12 m68hc11-elf
2693 UltraSparc running GNU/Linux sparc64-*-linux*
2695 * OBSOLETE configurations and files
2697 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2698 Harris/CXUX m88k m88*-harris-cxux*
2699 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2700 ns32k-utek-sysv* ns32k-utek-*
2701 TI TMS320C80 tic80-*-*
2703 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2704 PowerPC Solaris powerpcle-*-solaris*
2705 PowerPC Windows NT powerpcle-*-cygwin32
2706 PowerPC Netware powerpc-*-netware*
2707 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2708 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2709 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2710 Apple Macintosh (MPW) host N/A
2712 stuff.c (Program to stuff files into a specially prepared space in kdb)
2713 kdb-start.c (Main loop for the standalone kernel debugger)
2715 Configurations that have been declared obsolete in this release have
2716 been commented out. Unless there is activity to revive these
2717 configurations, the next release of GDB will have their sources
2718 permanently REMOVED.
2720 * REMOVED configurations and files
2722 Altos 3068 m68*-altos-*
2723 Convex c1-*-*, c2-*-*
2725 ARM RISCix arm-*-* (as host)
2729 * GDB has been converted to ISO C.
2731 GDB's source code has been converted to ISO C. In particular, the
2732 sources are fully protoized, and rely on standard headers being
2737 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2739 * The MI enabled by default.
2741 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2742 revised and enabled by default. Packages which use GDB as a debugging
2743 engine behind a UI or another front end are encouraged to switch to
2744 using the GDB/MI interface, instead of the old annotations interface
2745 which is now deprecated.
2747 * Support for debugging Pascal programs.
2749 GDB now includes support for debugging Pascal programs. The following
2750 main features are supported:
2752 - Pascal-specific data types such as sets;
2754 - automatic recognition of Pascal sources based on file-name
2757 - Pascal-style display of data types, variables, and functions;
2759 - a Pascal expression parser.
2761 However, some important features are not yet supported.
2763 - Pascal string operations are not supported at all;
2765 - there are some problems with boolean types;
2767 - Pascal type hexadecimal constants are not supported
2768 because they conflict with the internal variables format;
2770 - support for Pascal objects and classes is not full yet;
2772 - unlike Pascal, GDB is case-sensitive for symbol names.
2774 * Changes in completion.
2776 Commands such as `shell', `run' and `set args', which pass arguments
2777 to inferior programs, now complete on file names, similar to what
2778 users expect at the shell prompt.
2780 Commands which accept locations, such as `disassemble', `print',
2781 `breakpoint', `until', etc. now complete on filenames as well as
2782 program symbols. Thus, if you type "break foob TAB", and the source
2783 files linked into the programs include `foobar.c', that file name will
2784 be one of the candidates for completion. However, file names are not
2785 considered for completion after you typed a colon that delimits a file
2786 name from a name of a function in that file, as in "break foo.c:bar".
2788 `set demangle-style' completes on available demangling styles.
2790 * New platform-independent commands:
2792 It is now possible to define a post-hook for a command as well as a
2793 hook that runs before the command. For more details, see the
2794 documentation of `hookpost' in the GDB manual.
2796 * Changes in GNU/Linux native debugging.
2798 Support for debugging multi-threaded programs has been completely
2799 revised for all platforms except m68k and sparc. You can now debug as
2800 many threads as your system allows you to have.
2802 Attach/detach is supported for multi-threaded programs.
2804 Support for SSE registers was added for x86. This doesn't work for
2805 multi-threaded programs though.
2807 * Changes in MIPS configurations.
2809 Multi-arch support is enabled for all MIPS configurations.
2811 GDB can now be built as native debugger on SGI Irix 6.x systems for
2812 debugging n32 executables. (Debugging 64-bit executables is not yet
2815 * Unified support for hardware watchpoints in all x86 configurations.
2817 Most (if not all) native x86 configurations support hardware-assisted
2818 breakpoints and watchpoints in a unified manner. This support
2819 implements debug register sharing between watchpoints, which allows to
2820 put a virtually infinite number of watchpoints on the same address,
2821 and also supports watching regions up to 16 bytes with several debug
2824 The new maintenance command `maintenance show-debug-regs' toggles
2825 debugging print-outs in functions that insert, remove, and test
2826 watchpoints and hardware breakpoints.
2828 * Changes in the DJGPP native configuration.
2830 New command ``info dos sysinfo'' displays assorted information about
2831 the CPU, OS, memory, and DPMI server.
2833 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2834 display information about segment descriptors stored in GDT, LDT, and
2837 New commands ``info dos pde'' and ``info dos pte'' display entries
2838 from Page Directory and Page Tables (for now works with CWSDPMI only).
2839 New command ``info dos address-pte'' displays the Page Table entry for
2840 a given linear address.
2842 GDB can now pass command lines longer than 126 characters to the
2843 program being debugged (requires an update to the libdbg.a library
2844 which is part of the DJGPP development kit).
2846 DWARF2 debug info is now supported.
2848 It is now possible to `step' and `next' through calls to `longjmp'.
2850 * Changes in documentation.
2852 All GDB documentation was converted to GFDL, the GNU Free
2853 Documentation License.
2855 Tracepoints-related commands are now fully documented in the GDB
2858 TUI, the Text-mode User Interface, is now documented in the manual.
2860 Tracepoints-related commands are now fully documented in the GDB
2863 The "GDB Internals" manual now has an index. It also includes
2864 documentation of `ui_out' functions, GDB coding standards, x86
2865 hardware watchpoints, and memory region attributes.
2867 * GDB's version number moved to ``version.in''
2869 The Makefile variable VERSION has been replaced by the file
2870 ``version.in''. People creating GDB distributions should update the
2871 contents of this file.
2875 GUD support is now a standard part of the EMACS distribution.
2877 *** Changes in GDB 5.0:
2879 * Improved support for debugging FP programs on x86 targets
2881 Unified and much-improved support for debugging floating-point
2882 programs on all x86 targets. In particular, ``info float'' now
2883 displays the FP registers in the same format on all x86 targets, with
2884 greater level of detail.
2886 * Improvements and bugfixes in hardware-assisted watchpoints
2888 It is now possible to watch array elements, struct members, and
2889 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2890 on x86 targets no longer erroneously trigger when the address is
2893 * Improvements in the native DJGPP version of GDB
2895 The distribution now includes all the scripts and auxiliary files
2896 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2897 machines ``out of the box''.
2899 The DJGPP version can now debug programs that use signals. It is
2900 possible to catch signals that happened in the debuggee, deliver
2901 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2902 would kill the program being debugged.) Programs that hook hardware
2903 interrupts (keyboard, timer, etc.) can also be debugged.
2905 It is now possible to debug DJGPP programs that redirect their
2906 standard handles or switch them to raw (as opposed to cooked) mode, or
2907 even close them. The command ``run < foo > bar'' works as expected,
2908 and ``info terminal'' reports useful information about the debuggee's
2909 terminal, including raw/cooked mode, redirection, etc.
2911 The DJGPP version now uses termios functions for console I/O, which
2912 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2915 DOS-style file names with drive letters are now fully supported by
2918 It is now possible to debug DJGPP programs that switch their working
2919 directory. It is also possible to rerun the debuggee any number of
2920 times without restarting GDB; thus, you can use the same setup,
2921 breakpoints, etc. for many debugging sessions.
2923 * New native configurations
2925 ARM GNU/Linux arm*-*-linux*
2926 PowerPC GNU/Linux powerpc-*-linux*
2930 Motorola MCore mcore-*-*
2931 x86 VxWorks i[3456]86-*-vxworks*
2932 PowerPC VxWorks powerpc-*-vxworks*
2933 TI TMS320C80 tic80-*-*
2935 * OBSOLETE configurations
2937 Altos 3068 m68*-altos-*
2938 Convex c1-*-*, c2-*-*
2940 ARM RISCix arm-*-* (as host)
2943 Configurations that have been declared obsolete will be commented out,
2944 but the code will be left in place. If there is no activity to revive
2945 these configurations before the next release of GDB, the sources will
2946 be permanently REMOVED.
2948 * Gould support removed
2950 Support for the Gould PowerNode and NP1 has been removed.
2952 * New features for SVR4
2954 On SVR4 native platforms (such as Solaris), if you attach to a process
2955 without first loading a symbol file, GDB will now attempt to locate and
2956 load symbols from the running process's executable file.
2958 * Many C++ enhancements
2960 C++ support has been greatly improved. Overload resolution now works properly
2961 in almost all cases. RTTI support is on the way.
2963 * Remote targets can connect to a sub-program
2965 A popen(3) style serial-device has been added. This device starts a
2966 sub-process (such as a stand-alone simulator) and then communicates
2967 with that. The sub-program to run is specified using the syntax
2968 ``|<program> <args>'' vis:
2970 (gdb) set remotedebug 1
2971 (gdb) target extended-remote |mn10300-elf-sim program-args
2973 * MIPS 64 remote protocol
2975 A long standing bug in the mips64 remote protocol where by GDB
2976 expected certain 32 bit registers (ex SR) to be transfered as 32
2977 instead of 64 bits has been fixed.
2979 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2980 added to provide backward compatibility with older versions of GDB.
2982 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2984 The command ``set remotebinarydownload'' command has been replaced by
2985 ``set remote X-packet''. Other commands in ``set remote'' family
2986 include ``set remote P-packet''.
2988 * Breakpoint commands accept ranges.
2990 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2991 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2992 ``tracepoint passcount'' also accepts a range of tracepoints.
2994 * ``apropos'' command added.
2996 The ``apropos'' command searches through command names and
2997 documentation strings, printing out matches, making it much easier to
2998 try to find a command that does what you are looking for.
3002 A new machine oriented interface (MI) has been added to GDB. This
3003 interface is designed for debug environments running GDB as a separate
3004 process. This is part of the long term libGDB project. See the
3005 "GDB/MI" chapter of the GDB manual for further information. It can be
3006 enabled by configuring with:
3008 .../configure --enable-gdbmi
3010 *** Changes in GDB-4.18:
3012 * New native configurations
3014 HP-UX 10.20 hppa*-*-hpux10.20
3015 HP-UX 11.x hppa*-*-hpux11.0*
3016 M68K GNU/Linux m68*-*-linux*
3020 Fujitsu FR30 fr30-*-elf*
3021 Intel StrongARM strongarm-*-*
3022 Mitsubishi D30V d30v-*-*
3024 * OBSOLETE configurations
3026 Gould PowerNode, NP1 np1-*-*, pn-*-*
3028 Configurations that have been declared obsolete will be commented out,
3029 but the code will be left in place. If there is no activity to revive
3030 these configurations before the next release of GDB, the sources will
3031 be permanently REMOVED.
3035 As a compatibility experiment, GDB's source files buildsym.h and
3036 buildsym.c have been converted to pure standard C, no longer
3037 containing any K&R compatibility code. We believe that all systems in
3038 use today either come with a standard C compiler, or have a GCC port
3039 available. If this is not true, please report the affected
3040 configuration to bug-gdb@gnu.org immediately. See the README file for
3041 information about getting a standard C compiler if you don't have one
3046 GDB now uses readline 2.2.
3048 * set extension-language
3050 You can now control the mapping between filename extensions and source
3051 languages by using the `set extension-language' command. For instance,
3052 you can ask GDB to treat .c files as C++ by saying
3053 set extension-language .c c++
3054 The command `info extensions' lists all of the recognized extensions
3055 and their associated languages.
3057 * Setting processor type for PowerPC and RS/6000
3059 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3060 you can use the `set processor' command to specify what variant of the
3061 PowerPC family you are debugging. The command
3065 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3066 following PowerPC and RS6000 variants:
3068 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3069 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3071 403GC IBM PowerPC 403GC
3072 505 Motorola PowerPC 505
3073 860 Motorola PowerPC 860 or 850
3074 601 Motorola PowerPC 601
3075 602 Motorola PowerPC 602
3076 603 Motorola/IBM PowerPC 603 or 603e
3077 604 Motorola PowerPC 604 or 604e
3078 750 Motorola/IBM PowerPC 750 or 750
3080 At the moment, this command just tells GDB what to name the
3081 special-purpose processor registers. Since almost all the affected
3082 registers are inaccessible to user-level programs, this command is
3083 only useful for remote debugging in its present form.
3087 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3088 more extensive support for HP-UX. Added features include shared
3089 library support, kernel threads and hardware watchpoints for 11.00,
3090 support for HP's ANSI C and C++ compilers, and a compatibility mode
3091 for xdb and dbx commands.
3095 HP's donation includes the new concept of catchpoints, which is a
3096 generalization of the old catch command. On HP-UX, it is now possible
3097 to catch exec, fork, and vfork, as well as library loading.
3099 This means that the existing catch command has changed; its first
3100 argument now specifies the type of catch to be set up. See the
3101 output of "help catch" for a list of catchpoint types.
3103 * Debugging across forks
3105 On HP-UX, you can choose which process to debug when a fork() happens
3110 HP has donated a curses-based terminal user interface (TUI). To get
3111 it, build with --enable-tui. Although this can be enabled for any
3112 configuration, at present it only works for native HP debugging.
3114 * GDB remote protocol additions
3116 A new protocol packet 'X' that writes binary data is now available.
3117 Default behavior is to try 'X', then drop back to 'M' if the stub
3118 fails to respond. The settable variable `remotebinarydownload'
3119 allows explicit control over the use of 'X'.
3121 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3122 full 64-bit address. The command
3124 set remoteaddresssize 32
3126 can be used to revert to the old behaviour. For existing remote stubs
3127 the change should not be noticed, as the additional address information
3130 In order to assist in debugging stubs, you may use the maintenance
3131 command `packet' to send any text string to the stub. For instance,
3133 maint packet heythere
3135 sends the packet "$heythere#<checksum>". Note that it is very easy to
3136 disrupt a debugging session by sending the wrong packet at the wrong
3139 The compare-sections command allows you to compare section data on the
3140 target to what is in the executable file without uploading or
3141 downloading, by comparing CRC checksums.
3143 * Tracing can collect general expressions
3145 You may now collect general expressions at tracepoints. This requires
3146 further additions to the target-side stub; see tracepoint.c and
3147 doc/agentexpr.texi for further details.
3149 * mask-address variable for Mips
3151 For Mips targets, you may control the zeroing of the upper 32 bits of
3152 a 64-bit address by entering `set mask-address on'. This is mainly
3153 of interest to users of embedded R4xxx and R5xxx processors.
3155 * Higher serial baud rates
3157 GDB's serial code now allows you to specify baud rates 57600, 115200,
3158 230400, and 460800 baud. (Note that your host system may not be able
3159 to achieve all of these rates.)
3163 The i960 configuration now includes an initial implementation of a
3164 builtin simulator, contributed by Jim Wilson.
3167 *** Changes in GDB-4.17:
3169 * New native configurations
3171 Alpha GNU/Linux alpha*-*-linux*
3172 Unixware 2.x i[3456]86-unixware2*
3173 Irix 6.x mips*-sgi-irix6*
3174 PowerPC GNU/Linux powerpc-*-linux*
3175 PowerPC Solaris powerpcle-*-solaris*
3176 Sparc GNU/Linux sparc-*-linux*
3177 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3181 Argonaut Risc Chip (ARC) arc-*-*
3182 Hitachi H8/300S h8300*-*-*
3183 Matsushita MN10200 w/simulator mn10200-*-*
3184 Matsushita MN10300 w/simulator mn10300-*-*
3185 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3186 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3187 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3188 Mitsubishi D10V w/simulator d10v-*-*
3189 Mitsubishi M32R/D w/simulator m32r-*-elf*
3190 Tsqware Sparclet sparclet-*-*
3191 NEC V850 w/simulator v850-*-*
3193 * New debugging protocols
3195 ARM with RDI protocol arm*-*-*
3196 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3197 DDB and LSI variants of PMON protocol mips*-*-*
3198 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3199 PowerPC with SDS protocol powerpc{,le}-*-eabi
3200 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3204 All configurations can now understand and use the DWARF 2 debugging
3205 format. The choice is automatic, if the symbol file contains DWARF 2
3210 GDB now includes basic Java language support. This support is
3211 only useful with Java compilers that produce native machine code.
3213 * solib-absolute-prefix and solib-search-path
3215 For SunOS and SVR4 shared libraries, you may now set the prefix for
3216 loading absolute shared library symbol files, and the search path for
3217 locating non-absolute shared library symbol files.
3219 * Live range splitting
3221 GDB can now effectively debug code for which GCC has performed live
3222 range splitting as part of its optimization. See gdb/doc/LRS for
3223 more details on the expected format of the stabs information.
3227 GDB's support for the GNU Hurd, including thread debugging, has been
3228 updated to work with current versions of the Hurd.
3232 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3233 instruction set. ARM GDB automatically detects when Thumb
3234 instructions are in use, and adjusts disassembly and backtracing
3239 GDB's MIPS target configurations now handle the MIP16 16-bit
3244 GDB now includes support for overlays; if an executable has been
3245 linked such that multiple sections are based at the same address, GDB
3246 will decide which section to use for symbolic info. You can choose to
3247 control the decision manually, using overlay commands, or implement
3248 additional target-side support and use "overlay load-target" to bring
3249 in the overlay mapping. Do "help overlay" for more detail.
3253 The command "info symbol <address>" displays information about
3254 the symbol at the specified address.
3258 The standard remote protocol now includes an extension that allows
3259 asynchronous collection and display of trace data. This requires
3260 extensive support in the target-side debugging stub. Tracing mode
3261 includes a new interaction mode in GDB and new commands: see the
3262 file tracepoint.c for more details.
3266 Configurations for embedded MIPS now include a simulator contributed
3267 by Cygnus Solutions. The simulator supports the instruction sets
3268 of most MIPS variants.
3272 Sparc configurations may now include the ERC32 simulator contributed
3273 by the European Space Agency. The simulator is not built into
3274 Sparc targets by default; configure with --enable-sim to include it.
3278 For target configurations that may include multiple variants of a
3279 basic architecture (such as MIPS and SH), you may now set the
3280 architecture explicitly. "set arch" sets, "info arch" lists
3281 the possible architectures.
3283 *** Changes in GDB-4.16:
3285 * New native configurations
3287 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3288 M68K NetBSD m68k-*-netbsd*
3289 PowerPC AIX 4.x powerpc-*-aix*
3290 PowerPC MacOS powerpc-*-macos*
3291 PowerPC Windows NT powerpcle-*-cygwin32
3292 RS/6000 AIX 4.x rs6000-*-aix4*
3296 ARM with RDP protocol arm-*-*
3297 I960 with MON960 i960-*-coff
3298 MIPS VxWorks mips*-*-vxworks*
3299 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3300 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3302 Matra Sparclet sparclet-*-*
3306 The powerpc-eabi configuration now includes the PSIM simulator,
3307 contributed by Andrew Cagney, with assistance from Mike Meissner.
3308 PSIM is a very elaborate model of the PowerPC, including not only
3309 basic instruction set execution, but also details of execution unit
3310 performance and I/O hardware. See sim/ppc/README for more details.
3314 GDB now works with Solaris 2.5.
3316 * Windows 95/NT native
3318 GDB will now work as a native debugger on Windows 95 and Windows NT.
3319 To build it from source, you must use the "gnu-win32" environment,
3320 which uses a DLL to emulate enough of Unix to run the GNU tools.
3321 Further information, binaries, and sources are available at
3322 ftp.cygnus.com, under pub/gnu-win32.
3324 * dont-repeat command
3326 If a user-defined command includes the command `dont-repeat', then the
3327 command will not be repeated if the user just types return. This is
3328 useful if the command is time-consuming to run, so that accidental
3329 extra keystrokes don't run the same command many times.
3331 * Send break instead of ^C
3333 The standard remote protocol now includes an option to send a break
3334 rather than a ^C to the target in order to interrupt it. By default,
3335 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3337 * Remote protocol timeout
3339 The standard remote protocol includes a new variable `remotetimeout'
3340 that allows you to set the number of seconds before GDB gives up trying
3341 to read from the target. The default value is 2.
3343 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3345 By default GDB will automatically keep track of objects as they are
3346 loaded and unloaded by the dynamic linker. By using the command `set
3347 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3348 when shared library events occur, thus allowing you to set breakpoints
3349 in shared libraries which are explicitly loaded by the inferior.
3351 Note this feature does not work on hpux8. On hpux9 you must link
3352 /usr/lib/end.o into your program. This feature should work
3353 automatically on hpux10.
3355 * Irix 5.x hardware watchpoint support
3357 Irix 5 configurations now support the use of hardware watchpoints.
3359 * Mips protocol "SYN garbage limit"
3361 When debugging a Mips target using the `target mips' protocol, you
3362 may set the number of characters that GDB will ignore by setting
3363 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3364 every character. The default value is 1050.
3366 * Recording and replaying remote debug sessions
3368 If you set `remotelogfile' to the name of a file, gdb will write to it
3369 a recording of a remote debug session. This recording may then be
3370 replayed back to gdb using "gdbreplay". See gdbserver/README for
3371 details. This is useful when you have a problem with GDB while doing
3372 remote debugging; you can make a recording of the session and send it
3373 to someone else, who can then recreate the problem.
3375 * Speedups for remote debugging
3377 GDB includes speedups for downloading and stepping MIPS systems using
3378 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3379 and more efficient S-record downloading.
3381 * Memory use reductions and statistics collection
3383 GDB now uses less memory and reports statistics about memory usage.
3384 Try the `maint print statistics' command, for example.
3386 *** Changes in GDB-4.15:
3388 * Psymtabs for XCOFF
3390 The symbol reader for AIX GDB now uses partial symbol tables. This
3391 can greatly improve startup time, especially for large executables.
3393 * Remote targets use caching
3395 Remote targets now use a data cache to speed up communication with the
3396 remote side. The data cache could lead to incorrect results because
3397 it doesn't know about volatile variables, thus making it impossible to
3398 debug targets which use memory mapped I/O devices. `set remotecache
3399 off' turns the the data cache off.
3401 * Remote targets may have threads
3403 The standard remote protocol now includes support for multiple threads
3404 in the target system, using new protocol commands 'H' and 'T'. See
3405 gdb/remote.c for details.
3409 If GDB is configured with `--enable-netrom', then it will include
3410 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3411 acts as though it is a bank of ROM on the target board, but you can
3412 write into it over the network. GDB's support consists only of
3413 support for fast loading into the emulated ROM; to debug, you must use
3414 another protocol, such as standard remote protocol. The usual
3415 sequence is something like
3417 target nrom <netrom-hostname>
3419 target remote <netrom-hostname>:1235
3423 GDB now includes support for the Apple Macintosh, as a host only. It
3424 may be run as either an MPW tool or as a standalone application, and
3425 it can debug through the serial port. All the usual GDB commands are
3426 available, but to the target command, you must supply "serial" as the
3427 device type instead of "/dev/ttyXX". See mpw-README in the main
3428 directory for more information on how to build. The MPW configuration
3429 scripts */mpw-config.in support only a few targets, and only the
3430 mips-idt-ecoff target has been tested.
3434 GDB configuration now uses autoconf. This is not user-visible,
3435 but does simplify configuration and building.
3439 GDB now supports hpux10.
3441 *** Changes in GDB-4.14:
3443 * New native configurations
3445 x86 FreeBSD i[345]86-*-freebsd
3446 x86 NetBSD i[345]86-*-netbsd
3447 NS32k NetBSD ns32k-*-netbsd
3448 Sparc NetBSD sparc-*-netbsd
3452 A29K VxWorks a29k-*-vxworks
3453 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3454 CPU32 EST-300 emulator m68*-*-est*
3455 PowerPC ELF powerpc-*-elf
3458 * Alpha OSF/1 support for procfs
3460 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3461 possible to attach to running processes. As the mounting of the /proc
3462 filesystem is optional on the Alpha, GDB automatically determines
3463 the availability of /proc during startup. This can lead to problems
3464 if /proc is unmounted after GDB has been started.
3466 * Arguments to user-defined commands
3468 User commands may accept up to 10 arguments separated by whitespace.
3469 Arguments are accessed within the user command via $arg0..$arg9. A
3472 print $arg0 + $arg1 + $arg2
3474 To execute the command use:
3477 Defines the command "adder" which prints the sum of its three arguments.
3478 Note the arguments are text substitutions, so they may reference variables,
3479 use complex expressions, or even perform inferior function calls.
3481 * New `if' and `while' commands
3483 This makes it possible to write more sophisticated user-defined
3484 commands. Both commands take a single argument, which is the
3485 expression to evaluate, and must be followed by the commands to
3486 execute, one per line, if the expression is nonzero, the list being
3487 terminated by the word `end'. The `if' command list may include an
3488 `else' word, which causes the following commands to be executed only
3489 if the expression is zero.
3491 * Fortran source language mode
3493 GDB now includes partial support for Fortran 77. It will recognize
3494 Fortran programs and can evaluate a subset of Fortran expressions, but
3495 variables and functions may not be handled correctly. GDB will work
3496 with G77, but does not yet know much about symbols emitted by other
3499 * Better HPUX support
3501 Most debugging facilities now work on dynamic executables for HPPAs
3502 running hpux9 or later. You can attach to running dynamically linked
3503 processes, but by default the dynamic libraries will be read-only, so
3504 for instance you won't be able to put breakpoints in them. To change
3505 that behavior do the following before running the program:
3511 This will cause the libraries to be mapped private and read-write.
3512 To revert to the normal behavior, do this:
3518 You cannot set breakpoints or examine data in the library until after
3519 the library is loaded if the function/data symbols do not have
3522 GDB can now also read debug symbols produced by the HP C compiler on
3523 HPPAs (sorry, no C++, Fortran or 68k support).
3525 * Target byte order now dynamically selectable
3527 You can choose which byte order to use with a target system, via the
3528 commands "set endian big" and "set endian little", and you can see the
3529 current setting by using "show endian". You can also give the command
3530 "set endian auto", in which case GDB will use the byte order
3531 associated with the executable. Currently, only embedded MIPS
3532 configurations support dynamic selection of target byte order.
3534 * New DOS host serial code
3536 This version uses DPMI interrupts to handle buffered I/O, so you
3537 no longer need to run asynctsr when debugging boards connected to
3540 *** Changes in GDB-4.13:
3542 * New "complete" command
3544 This lists all the possible completions for the rest of the line, if it
3545 were to be given as a command itself. This is intended for use by emacs.
3547 * Trailing space optional in prompt
3549 "set prompt" no longer adds a space for you after the prompt you set. This
3550 allows you to set a prompt which ends in a space or one that does not.
3552 * Breakpoint hit counts
3554 "info break" now displays a count of the number of times the breakpoint
3555 has been hit. This is especially useful in conjunction with "ignore"; you
3556 can ignore a large number of breakpoint hits, look at the breakpoint info
3557 to see how many times the breakpoint was hit, then run again, ignoring one
3558 less than that number, and this will get you quickly to the last hit of
3561 * Ability to stop printing at NULL character
3563 "set print null-stop" will cause GDB to stop printing the characters of
3564 an array when the first NULL is encountered. This is useful when large
3565 arrays actually contain only short strings.
3567 * Shared library breakpoints
3569 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3570 breakpoints in shared libraries before the executable is run.
3572 * Hardware watchpoints
3574 There is a new hardware breakpoint for the watch command for sparclite
3575 targets. See gdb/sparclite/hw_breakpoint.note.
3577 Hardware watchpoints are also now supported under GNU/Linux.
3581 Annotations have been added. These are for use with graphical interfaces,
3582 and are still experimental. Currently only gdba.el uses these.
3584 * Improved Irix 5 support
3586 GDB now works properly with Irix 5.2.
3588 * Improved HPPA support
3590 GDB now works properly with the latest GCC and GAS.
3592 * New native configurations
3594 Sequent PTX4 i[34]86-sequent-ptx4
3595 HPPA running OSF/1 hppa*-*-osf*
3596 Atari TT running SVR4 m68*-*-sysv4*
3597 RS/6000 LynxOS rs6000-*-lynxos*
3601 OS/9000 i[34]86-*-os9k
3602 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3605 * Hitachi SH7000 and E7000-PC ICE support
3607 There is now support for communicating with the Hitachi E7000-PC ICE.
3608 This is available automatically when GDB is configured for the SH.
3612 As usual, a variety of small fixes and improvements, both generic
3613 and configuration-specific. See the ChangeLog for more detail.
3615 *** Changes in GDB-4.12:
3617 * Irix 5 is now supported
3621 GDB-4.12 on the HPPA has a number of changes which make it unable
3622 to debug the output from the currently released versions of GCC and
3623 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3624 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3625 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3628 *** Changes in GDB-4.11:
3630 * User visible changes:
3634 The "set remotedebug" option is now consistent between the mips remote
3635 target, remote targets using the gdb-specific protocol, UDI (AMD's
3636 debug protocol for the 29k) and the 88k bug monitor. It is now an
3637 integer specifying a debug level (normally 0 or 1, but 2 means more
3638 debugging info for the mips target).
3640 * DEC Alpha native support
3642 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3643 debug info, but GDB works fairly well with the DEC compiler and should
3644 work with a future GCC release. See the README file for a few
3645 Alpha-specific notes.
3647 * Preliminary thread implementation
3649 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3651 * LynxOS native and target support for 386
3653 This release has been hosted on LynxOS 2.2, and also can be configured
3654 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3657 * Improvements in C++ mangling/demangling.
3659 This release has much better g++ debugging, specifically in name
3660 mangling/demangling, virtual function calls, print virtual table,
3661 call methods, ...etc.
3663 *** Changes in GDB-4.10:
3665 * User visible changes:
3667 Remote debugging using the GDB-specific (`target remote') protocol now
3668 supports the `load' command. This is only useful if you have some
3669 other way of getting the stub to the target system, and you can put it
3670 somewhere in memory where it won't get clobbered by the download.
3672 Filename completion now works.
3674 When run under emacs mode, the "info line" command now causes the
3675 arrow to point to the line specified. Also, "info line" prints
3676 addresses in symbolic form (as well as hex).
3678 All vxworks based targets now support a user settable option, called
3679 vxworks-timeout. This option represents the number of seconds gdb
3680 should wait for responses to rpc's. You might want to use this if
3681 your vxworks target is, perhaps, a slow software simulator or happens
3682 to be on the far side of a thin network line.
3686 This release contains support for using a DEC alpha as a GDB host for
3687 cross debugging. Native alpha debugging is not supported yet.
3690 *** Changes in GDB-4.9:
3694 This is the first GDB release which is accompanied by a matching testsuite.
3695 The testsuite requires installation of dejagnu, which should be available
3696 via ftp from most sites that carry GNU software.
3700 'Cfront' style demangling has had its name changed to 'ARM' style, to
3701 emphasize that it was written from the specifications in the C++ Annotated
3702 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3703 disclaimers, it still generated too much confusion with users attempting to
3704 use gdb with AT&T cfront.
3708 GDB now uses a standard remote interface to a simulator library.
3709 So far, the library contains simulators for the Zilog Z8001/2, the
3710 Hitachi H8/300, H8/500 and Super-H.
3712 * New targets supported
3714 H8/300 simulator h8300-hitachi-hms or h8300hms
3715 H8/500 simulator h8500-hitachi-hms or h8500hms
3716 SH simulator sh-hitachi-hms or sh
3717 Z8000 simulator z8k-zilog-none or z8ksim
3718 IDT MIPS board over serial line mips-idt-ecoff
3720 Cross-debugging to GO32 targets is supported. It requires a custom
3721 version of the i386-stub.c module which is integrated with the
3722 GO32 memory extender.
3724 * New remote protocols
3726 MIPS remote debugging protocol.
3728 * New source languages supported
3730 This version includes preliminary support for Chill, a Pascal like language
3731 used by telecommunications companies. Chill support is also being integrated
3732 into the GNU compiler, but we don't know when it will be publically available.
3735 *** Changes in GDB-4.8:
3737 * HP Precision Architecture supported
3739 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3740 version of this support was available as a set of patches from the
3741 University of Utah. GDB does not support debugging of programs
3742 compiled with the HP compiler, because HP will not document their file
3743 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3744 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3746 Many problems in the preliminary version have been fixed.
3748 * Faster and better demangling
3750 We have improved template demangling and fixed numerous bugs in the GNU style
3751 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3752 character types (wchar_t) are now supported. Demangling of each symbol is now
3753 only done once, and is cached when the symbol table for a file is read in.
3754 This results in a small increase in memory usage for C programs, a moderate
3755 increase in memory usage for C++ programs, and a fantastic speedup in
3758 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3759 from the specifications in the Annotated Reference Manual, which AT&T's
3760 compiler does not actually implement.
3762 * G++ multiple inheritance compiler problem
3764 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3765 inheritance lattices was reworked to properly discover ambiguities. We
3766 recently found an example which causes this new algorithm to fail in a
3767 very subtle way, producing bad debug information for those classes.
3768 The file 'gcc.patch' (in this directory) can be applied to gcc to
3769 circumvent the problem. A future GCC release will contain a complete
3772 The previous G++ debug info problem (mentioned below for the gdb-4.7
3773 release) is fixed in gcc version 2.3.2.
3775 * Improved configure script
3777 The `configure' script will now attempt to guess your system type if
3778 you don't supply a host system type. The old scheme of supplying a
3779 host system triplet is preferable over using this. All the magic is
3780 done in the new `config.guess' script. Examine it for details.
3782 We have also brought our configure script much more in line with the FSF's
3783 version. It now supports the --with-xxx options. In particular,
3784 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3785 The resulting GDB will not be able to read arbitrary object file formats --
3786 only the format ``expected'' to be used on the configured target system.
3787 We hope to make this the default in a future release.
3789 * Documentation improvements
3791 There's new internal documentation on how to modify GDB, and how to
3792 produce clean changes to the code. We implore people to read it
3793 before submitting changes.
3795 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3796 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3797 `info' files are also provided. To build `info' files from scratch,
3798 you will need the latest `makeinfo' release, which will be available in
3799 a future texinfo-X.Y release.
3801 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3802 We're not sure exactly which versions have this problem, but it has
3803 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3804 or better. If that isn't possible, there is a patch in
3805 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3806 around this problem.
3810 GDB now supports array constants that can be used in expressions typed in by
3811 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3812 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3815 The new directory `gdb/sparclite' contains a program that demonstrates
3816 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3818 * New native hosts supported
3820 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3821 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3823 * New targets supported
3825 AMD 29k family via UDI a29k-amd-udi or udi29k
3827 * New file formats supported
3829 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3830 HPUX core files, and SCO 3.2v2 core files.
3834 Attaching to processes now works again; thanks for the many bug reports.
3836 We have also stomped on a bunch of core dumps caused by
3837 printf_filtered("%s") problems.
3839 We eliminated a copyright problem on the rpc and ptrace header files
3840 for VxWorks, which was discovered at the last minute during the 4.7
3841 release. You should now be able to build a VxWorks GDB.
3843 You can now interrupt gdb while an attached process is running. This
3844 will cause the attached process to stop, and give control back to GDB.
3846 We fixed problems caused by using too many file descriptors
3847 for reading symbols from object files and libraries. This was
3848 especially a problem for programs that used many (~100) shared
3851 The `step' command now only enters a subroutine if there is line number
3852 information for the subroutine. Otherwise it acts like the `next'
3853 command. Previously, `step' would enter subroutines if there was
3854 any debugging information about the routine. This avoids problems
3855 when using `cc -g1' on MIPS machines.
3857 * Internal improvements
3859 GDB's internal interfaces have been improved to make it easier to support
3860 debugging of multiple languages in the future.
3862 GDB now uses a common structure for symbol information internally.
3863 Minimal symbols (derived from linkage symbols in object files), partial
3864 symbols (from a quick scan of debug information), and full symbols
3865 contain a common subset of information, making it easier to write
3866 shared code that handles any of them.
3868 * New command line options
3870 We now accept --silent as an alias for --quiet.
3874 The memory-mapped-malloc library is now licensed under the GNU Library
3875 General Public License.
3877 *** Changes in GDB-4.7:
3879 * Host/native/target split
3881 GDB has had some major internal surgery to untangle the support for
3882 hosts and remote targets. Now, when you configure GDB for a remote
3883 target, it will no longer load in all of the support for debugging
3884 local programs on the host. When fully completed and tested, this will
3885 ensure that arbitrary host/target combinations are possible.
3887 The primary conceptual shift is to separate the non-portable code in
3888 GDB into three categories. Host specific code is required any time GDB
3889 is compiled on that host, regardless of the target. Target specific
3890 code relates to the peculiarities of the target, but can be compiled on
3891 any host. Native specific code is everything else: it can only be
3892 built when the host and target are the same system. Child process
3893 handling and core file support are two common `native' examples.
3895 GDB's use of /proc for controlling Unix child processes is now cleaner.
3896 It has been split out into a single module under the `target_ops' vector,
3897 plus two native-dependent functions for each system that uses /proc.
3899 * New hosts supported
3901 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3902 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3903 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3905 * New targets supported
3907 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3908 68030 and CPU32 m68030-*-*, m68332-*-*
3910 * New native hosts supported
3912 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3913 (386bsd is not well tested yet)
3914 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3916 * New file formats supported
3918 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3919 supports reading of `a.out.adobe' object files, which are an a.out
3920 format extended with minimal information about multiple sections.
3924 `show copying' is the same as the old `info copying'.
3925 `show warranty' is the same as `info warrantee'.
3926 These were renamed for consistency. The old commands continue to work.
3928 `info handle' is a new alias for `info signals'.
3930 You can now define pre-command hooks, which attach arbitrary command
3931 scripts to any command. The commands in the hook will be executed
3932 prior to the user's command. You can also create a hook which will be
3933 executed whenever the program stops. See gdb.texinfo.
3937 We now deal with Cfront style name mangling, and can even extract type
3938 info from mangled symbols. GDB can automatically figure out which
3939 symbol mangling style your C++ compiler uses.
3941 Calling of methods and virtual functions has been improved as well.
3945 The crash that occured when debugging Sun Ansi-C compiled binaries is
3946 fixed. This was due to mishandling of the extra N_SO stabs output
3949 We also finally got Ultrix 4.2 running in house, and fixed core file
3950 support, with help from a dozen people on the net.
3952 John M. Farrell discovered that the reason that single-stepping was so
3953 slow on all of the Mips based platforms (primarily SGI and DEC) was
3954 that we were trying to demangle and lookup a symbol used for internal
3955 purposes on every instruction that was being stepped through. Changing
3956 the name of that symbol so that it couldn't be mistaken for a C++
3957 mangled symbol sped things up a great deal.
3959 Rich Pixley sped up symbol lookups in general by getting much smarter
3960 about when C++ symbol mangling is necessary. This should make symbol
3961 completion (TAB on the command line) much faster. It's not as fast as
3962 we'd like, but it's significantly faster than gdb-4.6.
3966 A new user controllable variable 'call_scratch_address' can
3967 specify the location of a scratch area to be used when GDB
3968 calls a function in the target. This is necessary because the
3969 usual method of putting the scratch area on the stack does not work
3970 in systems that have separate instruction and data spaces.
3972 We integrated changes to support the 29k UDI (Universal Debugger
3973 Interface), but discovered at the last minute that we didn't have all
3974 of the appropriate copyright paperwork. We are working with AMD to
3975 resolve this, and hope to have it available soon.
3979 We have sped up the remote serial line protocol, especially for targets
3980 with lots of registers. It now supports a new `expedited status' ('T')
3981 message which can be used in place of the existing 'S' status message.
3982 This allows the remote stub to send only the registers that GDB
3983 needs to make a quick decision about single-stepping or conditional
3984 breakpoints, eliminating the need to fetch the entire register set for
3985 each instruction being stepped through.
3987 The GDB remote serial protocol now implements a write-through cache for
3988 registers, only re-reading the registers if the target has run.
3990 There is also a new remote serial stub for SPARC processors. You can
3991 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3992 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3993 processor with a serial port.
3997 Configure.in files have become much easier to read and modify. A new
3998 `table driven' format makes it more obvious what configurations are
3999 supported, and what files each one uses.
4003 There is a new opcodes library which will eventually contain all of the
4004 disassembly routines and opcode tables. At present, it only contains
4005 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4006 disassembler (binutils/objdump) to share these routines.
4008 The libiberty library is now copylefted under the GNU Library General
4009 Public License. This allows more liberal use, and was done so libg++
4010 can use it. This makes no difference to GDB, since the Library License
4011 grants all the rights from the General Public License.
4015 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4016 reference to the stabs symbol info used by the debugger. It is (as far
4017 as we know) the only published document on this fascinating topic. We
4018 encourage you to read it, compare it to the stabs information on your
4019 system, and send improvements on the document in general (to
4020 bug-gdb@prep.ai.mit.edu).
4022 And, of course, many bugs have been fixed.
4025 *** Changes in GDB-4.6:
4027 * Better support for C++ function names
4029 GDB now accepts as input the "demangled form" of C++ overloaded function
4030 names and member function names, and can do command completion on such names
4031 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4032 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4033 Make use of command completion, it is your friend.
4035 GDB also now accepts a variety of C++ mangled symbol formats. They are
4036 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4037 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4038 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4039 for the list of formats.
4041 * G++ symbol mangling problem
4043 Recent versions of gcc have a bug in how they emit debugging information for
4044 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4045 directory) can be applied to gcc to fix the problem. Alternatively, if you
4046 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4047 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4048 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4051 * New 'maintenance' command
4053 All of the commands related to hacking GDB internals have been moved out of
4054 the main command set, and now live behind the 'maintenance' command. This
4055 can also be abbreviated as 'mt'. The following changes were made:
4057 dump-me -> maintenance dump-me
4058 info all-breakpoints -> maintenance info breakpoints
4059 printmsyms -> maintenance print msyms
4060 printobjfiles -> maintenance print objfiles
4061 printpsyms -> maintenance print psymbols
4062 printsyms -> maintenance print symbols
4064 The following commands are new:
4066 maintenance demangle Call internal GDB demangler routine to
4067 demangle a C++ link name and prints the result.
4068 maintenance print type Print a type chain for a given symbol
4070 * Change to .gdbinit file processing
4072 We now read the $HOME/.gdbinit file before processing the argv arguments
4073 (e.g. reading symbol files or core files). This allows global parameters to
4074 be set, which will apply during the symbol reading. The ./.gdbinit is still
4075 read after argv processing.
4077 * New hosts supported
4079 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4081 GNU/Linux support i386-unknown-linux or linux
4083 We are also including code to support the HP/PA running BSD and HPUX. This
4084 is almost guaranteed not to work, as we didn't have time to test or build it
4085 for this release. We are including it so that the more adventurous (or
4086 masochistic) of you can play with it. We also had major problems with the
4087 fact that the compiler that we got from HP doesn't support the -g option.
4090 * New targets supported
4092 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4094 * More smarts about finding #include files
4096 GDB now remembers the compilation directory for all include files, and for
4097 all files from which C is generated (like yacc and lex sources). This
4098 greatly improves GDB's ability to find yacc/lex sources, and include files,
4099 especially if you are debugging your program from a directory different from
4100 the one that contains your sources.
4102 We also fixed a bug which caused difficulty with listing and setting
4103 breakpoints in include files which contain C code. (In the past, you had to
4104 try twice in order to list an include file that you hadn't looked at before.)
4106 * Interesting infernals change
4108 GDB now deals with arbitrary numbers of sections, where the symbols for each
4109 section must be relocated relative to that section's landing place in the
4110 target's address space. This work was needed to support ELF with embedded
4111 stabs used by Solaris-2.0.
4113 * Bug fixes (of course!)
4115 There have been loads of fixes for the following things:
4116 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4117 i960, stabs, DOS(GO32), procfs, etc...
4119 See the ChangeLog for details.
4121 *** Changes in GDB-4.5:
4123 * New machines supported (host and target)
4125 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4127 SGI Irix-4.x mips-sgi-irix4 or iris4
4129 * New malloc package
4131 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4132 Mmalloc is capable of handling mutiple heaps of memory. It is also
4133 capable of saving a heap to a file, and then mapping it back in later.
4134 This can be used to greatly speedup the startup of GDB by using a
4135 pre-parsed symbol table which lives in a mmalloc managed heap. For
4136 more details, please read mmalloc/mmalloc.texi.
4140 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4141 'help info proc' for details.
4143 * MIPS ecoff symbol table format
4145 The code that reads MIPS symbol table format is now supported on all hosts.
4146 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4149 * File name changes for MS-DOS
4151 Many files in the config directories have been renamed to make it easier to
4152 support GDB on MS-DOSe systems (which have very restrictive file name
4153 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4154 environment) is close to working but has some remaining problems. Note
4155 that debugging of DOS programs is not supported, due to limitations
4156 in the ``operating system'', but it can be used to host cross-debugging.
4158 * Cross byte order fixes
4160 Many fixes have been made to support cross debugging of Sparc and MIPS
4161 targets from hosts whose byte order differs.
4163 * New -mapped and -readnow options
4165 If memory-mapped files are available on your system through the 'mmap'
4166 system call, you can use the -mapped option on the `file' or
4167 `symbol-file' commands to cause GDB to write the symbols from your
4168 program into a reusable file. If the program you are debugging is
4169 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4170 Future GDB debugging sessions will notice the presence of this file,
4171 and will quickly map in symbol information from it, rather than reading
4172 the symbol table from the executable program. Using the '-mapped'
4173 option in a GDB `file' or `symbol-file' command has the same effect as
4174 starting GDB with the '-mapped' command-line option.
4176 You can cause GDB to read the entire symbol table immediately by using
4177 the '-readnow' option with any of the commands that load symbol table
4178 information (or on the GDB command line). This makes the command
4179 slower, but makes future operations faster.
4181 The -mapped and -readnow options are typically combined in order to
4182 build a `fred.syms' file that contains complete symbol information.
4183 A simple GDB invocation to do nothing but build a `.syms' file for future
4186 gdb -batch -nx -mapped -readnow programname
4188 The `.syms' file is specific to the host machine on which GDB is run.
4189 It holds an exact image of GDB's internal symbol table. It cannot be
4190 shared across multiple host platforms.
4192 * longjmp() handling
4194 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4195 siglongjmp() without losing control. This feature has not yet been ported to
4196 all systems. It currently works on many 386 platforms, all MIPS-based
4197 platforms (SGI, DECstation, etc), and Sun3/4.
4201 Preliminary work has been put in to support the new Solaris OS from Sun. At
4202 this time, it can control and debug processes, but it is not capable of
4207 As always, many many bug fixes. The major areas were with g++, and mipsread.
4208 People using the MIPS-based platforms should experience fewer mysterious
4209 crashes and trashed symbol tables.
4211 *** Changes in GDB-4.4:
4213 * New machines supported (host and target)
4215 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4217 BSD Reno on Vax vax-dec-bsd
4218 Ultrix on Vax vax-dec-ultrix
4220 * New machines supported (target)
4222 AMD 29000 embedded, using EBMON a29k-none-none
4226 GDB continues to improve its handling of C++. `References' work better.
4227 The demangler has also been improved, and now deals with symbols mangled as
4228 per the Annotated C++ Reference Guide.
4230 GDB also now handles `stabs' symbol information embedded in MIPS
4231 `ecoff' symbol tables. Since the ecoff format was not easily
4232 extensible to handle new languages such as C++, this appeared to be a
4233 good way to put C++ debugging info into MIPS binaries. This option
4234 will be supported in the GNU C compiler, version 2, when it is
4237 * New features for SVR4
4239 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4240 shared libraries. Debugging dynamically linked programs should present
4241 only minor differences from debugging statically linked programs.
4243 The `info proc' command will print out information about any process
4244 on an SVR4 system (including the one you are debugging). At the moment,
4245 it prints the address mappings of the process.
4247 If you bring up GDB on another SVR4 system, please send mail to
4248 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4250 * Better dynamic linking support in SunOS
4252 Reading symbols from shared libraries which contain debugging symbols
4253 now works properly. However, there remain issues such as automatic
4254 skipping of `transfer vector' code during function calls, which
4255 make it harder to debug code in a shared library, than to debug the
4256 same code linked statically.
4260 GDB is now using the latest `getopt' routines from the FSF. This
4261 version accepts the -- prefix for options with long names. GDB will
4262 continue to accept the old forms (-option and +option) as well.
4263 Various single letter abbreviations for options have been explicity
4264 added to the option table so that they won't get overshadowed in the
4265 future by other options that begin with the same letter.
4269 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4270 Many assorted bugs have been handled. Many more remain to be handled.
4271 See the various ChangeLog files (primarily in gdb and bfd) for details.
4274 *** Changes in GDB-4.3:
4276 * New machines supported (host and target)
4278 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4279 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4280 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4282 * Almost SCO Unix support
4284 We had hoped to support:
4285 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4286 (except for core file support), but we discovered very late in the release
4287 that it has problems with process groups that render gdb unusable. Sorry
4288 about that. I encourage people to fix it and post the fixes.
4290 * Preliminary ELF and DWARF support
4292 GDB can read ELF object files on System V Release 4, and can handle
4293 debugging records for C, in DWARF format, in ELF files. This support
4294 is preliminary. If you bring up GDB on another SVR4 system, please
4295 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4300 GDB now uses the latest `readline' library. One user-visible change
4301 is that two tabs will list possible command completions, which previously
4302 required typing M-? (meta-question mark, or ESC ?).
4306 The `stepi' bug that many of you noticed has been squashed.
4307 Many bugs in C++ have been handled. Many more remain to be handled.
4308 See the various ChangeLog files (primarily in gdb and bfd) for details.
4310 * State of the MIPS world (in case you wondered):
4312 GDB can understand the symbol tables emitted by the compilers
4313 supplied by most vendors of MIPS-based machines, including DEC. These
4314 symbol tables are in a format that essentially nobody else uses.
4316 Some versions of gcc come with an assembler post-processor called
4317 mips-tfile. This program is required if you want to do source-level
4318 debugging of gcc-compiled programs. I believe FSF does not ship
4319 mips-tfile with gcc version 1, but it will eventually come with gcc
4322 Debugging of g++ output remains a problem. g++ version 1.xx does not
4323 really support it at all. (If you're lucky, you should be able to get
4324 line numbers and stack traces to work, but no parameters or local
4325 variables.) With some work it should be possible to improve the
4328 When gcc version 2 is released, you will have somewhat better luck.
4329 However, even then you will get confusing results for inheritance and
4332 We will eventually provide full debugging of g++ output on
4333 DECstations. This will probably involve some kind of stabs-in-ecoff
4334 encapulation, but the details have not been worked out yet.
4337 *** Changes in GDB-4.2:
4339 * Improved configuration
4341 Only one copy of `configure' exists now, and it is not self-modifying.
4342 Porting BFD is simpler.
4346 The `step' and `next' commands now only stop at the first instruction
4347 of a source line. This prevents the multiple stops that used to occur
4348 in switch statements, for-loops, etc. `Step' continues to stop if a
4349 function that has debugging information is called within the line.
4353 Lots of small bugs fixed. More remain.
4355 * New host supported (not target)
4357 Intel 386 PC clone running Mach i386-none-mach
4360 *** Changes in GDB-4.1:
4362 * Multiple source language support
4364 GDB now has internal scaffolding to handle several source languages.
4365 It determines the type of each source file from its filename extension,
4366 and will switch expression parsing and number formatting to match the
4367 language of the function in the currently selected stack frame.
4368 You can also specifically set the language to be used, with
4369 `set language c' or `set language modula-2'.
4373 GDB now has preliminary support for the GNU Modula-2 compiler,
4374 currently under development at the State University of New York at
4375 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4376 continue through the fall of 1991 and into 1992.
4378 Other Modula-2 compilers are currently not supported, and attempting to
4379 debug programs compiled with them will likely result in an error as the
4380 symbol table is read. Feel free to work on it, though!
4382 There are hooks in GDB for strict type checking and range checking,
4383 in the `Modula-2 philosophy', but they do not currently work.
4387 GDB can now write to executable and core files (e.g. patch
4388 a variable's value). You must turn this switch on, specify
4389 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4390 by assigning a new value to a variable. Modifications take
4393 * Automatic SunOS shared library reading
4395 When you run your program, GDB automatically determines where its
4396 shared libraries (if any) have been loaded, and reads their symbols.
4397 The `share' command is no longer needed. This also works when
4398 examining core files.
4402 You can specify the number of lines that the `list' command shows.
4405 * New machines supported (host and target)
4407 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4408 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4409 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4411 * New hosts supported (not targets)
4413 IBM RT/PC: romp-ibm-aix or rtpc
4415 * New targets supported (not hosts)
4417 AMD 29000 embedded with COFF a29k-none-coff
4418 AMD 29000 embedded with a.out a29k-none-aout
4419 Ultracomputer remote kernel debug a29k-nyu-kern
4421 * New remote interfaces
4427 *** Changes in GDB-4.0:
4431 Wide output is wrapped at good places to make the output more readable.
4433 Gdb now supports cross-debugging from a host machine of one type to a
4434 target machine of another type. Communication with the target system
4435 is over serial lines. The ``target'' command handles connecting to the
4436 remote system; the ``load'' command will download a program into the
4437 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4438 also supports debugging of realtime processes running under VxWorks,
4439 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4440 stub on the target system.
4442 New CPUs supported include the AMD 29000 and Intel 960.
4444 GDB now reads object files and symbol tables via a ``binary file''
4445 library, which allows a single copy of GDB to debug programs of multiple
4446 object file types such as a.out and coff.
4448 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4449 refcard.dvi and refcard.ps are available to format it).
4452 * Control-Variable user interface simplified
4454 All variables that control the operation of the debugger can be set
4455 by the ``set'' command, and displayed by the ``show'' command.
4457 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4458 ``Show prompt'' produces the response:
4459 Gdb's prompt is new-gdb=>.
4461 What follows are the NEW set commands. The command ``help set'' will
4462 print a complete list of old and new set commands. ``help set FOO''
4463 will give a longer description of the variable FOO. ``show'' will show
4464 all of the variable descriptions and their current settings.
4466 confirm on/off: Enables warning questions for operations that are
4467 hard to recover from, e.g. rerunning the program while
4468 it is already running. Default is ON.
4470 editing on/off: Enables EMACS style command line editing
4471 of input. Previous lines can be recalled with
4472 control-P, the current line can be edited with control-B,
4473 you can search for commands with control-R, etc.
4476 history filename NAME: NAME is where the gdb command history
4477 will be stored. The default is .gdb_history,
4478 or the value of the environment variable
4481 history size N: The size, in commands, of the command history. The
4482 default is 256, or the value of the environment variable
4485 history save on/off: If this value is set to ON, the history file will
4486 be saved after exiting gdb. If set to OFF, the
4487 file will not be saved. The default is OFF.
4489 history expansion on/off: If this value is set to ON, then csh-like
4490 history expansion will be performed on
4491 command line input. The default is OFF.
4493 radix N: Sets the default radix for input and output. It can be set
4494 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4495 in the current radix, so "set radix 10" is always a no-op.
4497 height N: This integer value is the number of lines on a page. Default
4498 is 24, the current `stty rows'' setting, or the ``li#''
4499 setting from the termcap entry matching the environment
4502 width N: This integer value is the number of characters on a line.
4503 Default is 80, the current `stty cols'' setting, or the ``co#''
4504 setting from the termcap entry matching the environment
4507 Note: ``set screensize'' is obsolete. Use ``set height'' and
4508 ``set width'' instead.
4510 print address on/off: Print memory addresses in various command displays,
4511 such as stack traces and structure values. Gdb looks
4512 more ``symbolic'' if you turn this off; it looks more
4513 ``machine level'' with it on. Default is ON.
4515 print array on/off: Prettyprint arrays. New convenient format! Default
4518 print demangle on/off: Print C++ symbols in "source" form if on,
4521 print asm-demangle on/off: Same, for assembler level printouts
4524 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4527 * Support for Epoch Environment.
4529 The epoch environment is a version of Emacs v18 with windowing. One
4530 new command, ``inspect'', is identical to ``print'', except that if you
4531 are running in the epoch environment, the value is printed in its own
4535 * Support for Shared Libraries
4537 GDB can now debug programs and core files that use SunOS shared libraries.
4538 Symbols from a shared library cannot be referenced
4539 before the shared library has been linked with the program (this
4540 happens after you type ``run'' and before the function main() is entered).
4541 At any time after this linking (including when examining core files
4542 from dynamically linked programs), gdb reads the symbols from each
4543 shared library when you type the ``sharedlibrary'' command.
4544 It can be abbreviated ``share''.
4546 sharedlibrary REGEXP: Load shared object library symbols for files
4547 matching a unix regular expression. No argument
4548 indicates to load symbols for all shared libraries.
4550 info sharedlibrary: Status of loaded shared libraries.
4555 A watchpoint stops execution of a program whenever the value of an
4556 expression changes. Checking for this slows down execution
4557 tremendously whenever you are in the scope of the expression, but is
4558 quite useful for catching tough ``bit-spreader'' or pointer misuse
4559 problems. Some machines such as the 386 have hardware for doing this
4560 more quickly, and future versions of gdb will use this hardware.
4562 watch EXP: Set a watchpoint (breakpoint) for an expression.
4564 info watchpoints: Information about your watchpoints.
4566 delete N: Deletes watchpoint number N (same as breakpoints).
4567 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4568 enable N: Re-enables watchpoint number N (same as breakpoints).
4571 * C++ multiple inheritance
4573 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4576 * C++ exception handling
4578 Gdb now supports limited C++ exception handling. Besides the existing
4579 ability to breakpoint on an exception handler, gdb can breakpoint on
4580 the raising of an exception (before the stack is peeled back to the
4583 catch FOO: If there is a FOO exception handler in the dynamic scope,
4584 set a breakpoint to catch exceptions which may be raised there.
4585 Multiple exceptions (``catch foo bar baz'') may be caught.
4587 info catch: Lists all exceptions which may be caught in the
4588 current stack frame.
4591 * Minor command changes
4593 The command ``call func (arg, arg, ...)'' now acts like the print
4594 command, except it does not print or save a value if the function's result
4595 is void. This is similar to dbx usage.
4597 The ``up'' and ``down'' commands now always print the frame they end up
4598 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4599 frames without printing.
4601 * New directory command
4603 'dir' now adds directories to the FRONT of the source search path.
4604 The path starts off empty. Source files that contain debug information
4605 about the directory in which they were compiled can be found even
4606 with an empty path; Sun CC and GCC include this information. If GDB can't
4607 find your source file in the current directory, type "dir .".
4609 * Configuring GDB for compilation
4611 For normal use, type ``./configure host''. See README or gdb.texinfo
4614 GDB now handles cross debugging. If you are remotely debugging between
4615 two different machines, type ``./configure host -target=targ''.
4616 Host is the machine where GDB will run; targ is the machine
4617 where the program that you are debugging will run.