1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.3
6 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
7 and "show remote hardware-watchpoint-length-limit". These allows to
8 set or show the maximum length limit (in bytes) of a remote
9 target hardware watchpoint.
11 This allows e.g. to use "unlimited" hardware watchpoints with the
12 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
13 watchpoints are slower than real hardware watchpoints but are
14 significantly faster than gdb software watchpoints.
18 ** The "maint set python print-stack on|off" command has been
19 deprecated, and a new command: "set python print-stack on|off" has
20 replaced it. Additionally, the default for "print-stack" is now
23 ** A prompt subsitution hook (prompt_hook) is now available to the
26 ** 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
111 * GDB has a new command: "thread find [REGEXP]".
112 It finds the thread id whose name, target id, or thread extra info
113 matches the given regular expression.
115 * The "catch syscall" command now works on mips*-linux* targets.
117 * The -data-disassemble MI command now supports modes 2 and 3 for
118 dumping the instruction opcodes.
120 * New command line options
122 -data-directory DIR Specify DIR as the "data-directory".
123 This is mostly for testing purposes.
125 * The "maint set python auto-load on|off" command has been renamed to
126 "set auto-load-scripts on|off".
128 * GDB has a new command: "set directories".
129 It is like the "dir" command except that it replaces the
130 source path list instead of augmenting it.
132 * GDB now understands thread names.
134 On GNU/Linux, "info threads" will display the thread name as set by
135 prctl or pthread_setname_np.
137 There is also a new command, "thread name", which can be used to
138 assign a name internally for GDB to display.
141 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
142 has been integrated into GDB.
146 ** The function gdb.Write now accepts an optional keyword 'stream'.
147 This keyword, when provided, will direct the output to either
148 stdout, stderr, or GDB's logging output.
150 ** Parameters can now be be sub-classed in Python, and in particular
151 you may implement the get_set_doc and get_show_doc functions.
152 This improves how Parameter set/show documentation is processed
153 and allows for more dynamic content.
155 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
156 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
157 have an is_valid method.
159 ** Breakpoints can now be sub-classed in Python, and in particular
160 you may implement a 'stop' function that is executed each time
161 the inferior reaches that breakpoint.
163 ** New function gdb.lookup_global_symbol looks up a global symbol.
165 ** GDB values in Python are now callable if the value represents a
166 function. For example, if 'some_value' represents a function that
167 takes two integer parameters and returns a value, you can call
168 that function like so:
170 result = some_value (10,20)
172 ** Module gdb.types has been added.
173 It contains a collection of utilities for working with gdb.Types objects:
174 get_basic_type, has_field, make_enum_dict.
176 ** Module gdb.printing has been added.
177 It contains utilities for writing and registering pretty-printers.
178 New classes: PrettyPrinter, SubPrettyPrinter,
179 RegexpCollectionPrettyPrinter.
180 New function: register_pretty_printer.
182 ** New commands "info pretty-printers", "enable pretty-printer" and
183 "disable pretty-printer" have been added.
185 ** gdb.parameter("directories") is now available.
187 ** New function gdb.newest_frame returns the newest frame in the
190 ** The gdb.InferiorThread class has a new "name" attribute. This
191 holds the thread's name.
193 ** Python Support for Inferior events.
194 Python scripts can add observers to be notified of events
195 occurring in the process being debugged.
196 The following events are currently supported:
197 - gdb.events.cont Continue event.
198 - gdb.events.exited Inferior exited event.
199 - gdb.events.stop Signal received, and Breakpoint hit events.
203 ** GDB now puts template parameters in scope when debugging in an
204 instantiation. For example, if you have:
206 template<int X> int func (void) { return X; }
208 then if you step into func<5>, "print X" will show "5". This
209 feature requires proper debuginfo support from the compiler; it
210 was added to GCC 4.5.
212 ** The motion commands "next", "finish", "until", and "advance" now
213 work better when exceptions are thrown. In particular, GDB will
214 no longer lose control of the inferior; instead, the GDB will
215 stop the inferior at the point at which the exception is caught.
216 This functionality requires a change in the exception handling
217 code that was introduced in GCC 4.5.
219 * GDB now follows GCC's rules on accessing volatile objects when
220 reading or writing target state during expression evaluation.
221 One notable difference to prior behavior is that "print x = 0"
222 no longer generates a read of x; the value of the assignment is
223 now always taken directly from the value being assigned.
225 * GDB now has some support for using labels in the program's source in
226 linespecs. For instance, you can use "advance label" to continue
227 execution to a label.
229 * GDB now has support for reading and writing a new .gdb_index
230 section. This section holds a fast index of DWARF debugging
231 information and can be used to greatly speed up GDB startup and
232 operation. See the documentation for `save gdb-index' for details.
234 * The "watch" command now accepts an optional "-location" argument.
235 When used, this causes GDB to watch the memory referred to by the
236 expression. Such a watchpoint is never deleted due to it going out
239 * GDB now supports thread debugging of core dumps on GNU/Linux.
241 GDB now activates thread debugging using the libthread_db library
242 when debugging GNU/Linux core dumps, similarly to when debugging
243 live processes. As a result, when debugging a core dump file, GDB
244 is now able to display pthread_t ids of threads. For example, "info
245 threads" shows the same output as when debugging the process when it
246 was live. In earlier releases, you'd see something like this:
249 * 1 LWP 6780 main () at main.c:10
251 While now you see this:
254 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
256 It is also now possible to inspect TLS variables when debugging core
259 When debugging a core dump generated on a machine other than the one
260 used to run GDB, you may need to point GDB at the correct
261 libthread_db library with the "set libthread-db-search-path"
262 command. See the user manual for more details on this command.
264 * When natively debugging programs on PowerPC BookE processors running
265 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
266 which stop execution of the inferior whenever it executes an instruction
267 at any address within the specified range. See the "PowerPC Embedded"
268 section in the user manual for more details.
270 * New features in the GDB remote stub, GDBserver
272 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
273 and i686 LynxOS (version 5.x).
275 ** GDBserver is now supported on Blackfin Linux.
277 * New native configurations
279 ia64 HP-UX ia64-*-hpux*
283 Analog Devices, Inc. Blackfin Processor bfin-*
285 * Ada task switching is now supported on sparc-elf targets when
286 debugging a program using the Ravenscar Profile. For more information,
287 see the "Tasking Support when using the Ravenscar Profile" section
288 in the GDB user manual.
290 * Guile support was removed.
292 * New features in the GNU simulator
294 ** The --map-info flag lists all known core mappings.
296 ** CFI flashes may be simulated via the "cfi" device.
298 *** Changes in GDB 7.2
300 * Shared library support for remote targets by default
302 When GDB is configured for a generic, non-OS specific target, like
303 for example, --target=arm-eabi or one of the many *-*-elf targets,
304 GDB now queries remote stubs for loaded shared libraries using the
305 `qXfer:libraries:read' packet. Previously, shared library support
306 was always disabled for such configurations.
310 ** Argument Dependent Lookup (ADL)
312 In C++ ADL lookup directs function search to the namespaces of its
313 arguments even if the namespace has not been imported.
323 Here the compiler will search for `foo' in the namespace of 'b'
324 and find A::foo. GDB now supports this. This construct is commonly
325 used in the Standard Template Library for operators.
327 ** Improved User Defined Operator Support
329 In addition to member operators, GDB now supports lookup of operators
330 defined in a namespace and imported with a `using' directive, operators
331 defined in the global scope, operators imported implicitly from an
332 anonymous namespace, and the ADL operators mentioned in the previous
334 GDB now also supports proper overload resolution for all the previously
335 mentioned flavors of operators.
337 ** static const class members
339 Printing of static const class members that are initialized in the
340 class definition has been fixed.
342 * Windows Thread Information Block access.
344 On Windows targets, GDB now supports displaying the Windows Thread
345 Information Block (TIB) structure. This structure is visible either
346 by using the new command `info w32 thread-information-block' or, by
347 dereferencing the new convenience variable named `$_tlb', a
348 thread-specific pointer to the TIB. This feature is also supported
349 when remote debugging using GDBserver.
353 Static tracepoints are calls in the user program into a tracing
354 library. One such library is a port of the LTTng kernel tracer to
355 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
356 When debugging with GDBserver, GDB now supports combining the GDB
357 tracepoint machinery with such libraries. For example: the user can
358 use GDB to probe a static tracepoint marker (a call from the user
359 program into the tracing library) with the new "strace" command (see
360 "New commands" below). This creates a "static tracepoint" in the
361 breakpoint list, that can be manipulated with the same feature set
362 as fast and regular tracepoints. E.g., collect registers, local and
363 global variables, collect trace state variables, and define
364 tracepoint conditions. In addition, the user can collect extra
365 static tracepoint marker specific data, by collecting the new
366 $_sdata internal variable. When analyzing the trace buffer, you can
367 inspect $_sdata like any other variable available to GDB. For more
368 information, see the "Tracepoints" chapter in GDB user manual. New
369 remote packets have been defined to support static tracepoints, see
370 the "New remote packets" section below.
372 * Better reconstruction of tracepoints after disconnected tracing
374 GDB will attempt to download the original source form of tracepoint
375 definitions when starting a trace run, and then will upload these
376 upon reconnection to the target, resulting in a more accurate
377 reconstruction of the tracepoints that are in use on the target.
381 You can now exercise direct control over the ways that GDB can
382 affect your program. For instance, you can disallow the setting of
383 breakpoints, so that the program can run continuously (assuming
384 non-stop mode). In addition, the "observer" variable is available
385 to switch all of the different controls; in observer mode, GDB
386 cannot affect the target's behavior at all, which is useful for
387 tasks like diagnosing live systems in the field.
389 * The new convenience variable $_thread holds the number of the
396 Return the address of the Windows Thread Information Block of a given thread.
400 In response to several of the tracepoint packets, the target may now
401 also respond with a number of intermediate `qRelocInsn' request
402 packets before the final result packet, to have GDB handle
403 relocating an instruction to execute at a different address. This
404 is particularly useful for stubs that support fast tracepoints. GDB
405 reports support for this feature in the qSupported packet.
409 List static tracepoint markers in the target program.
413 List static tracepoint markers at a given address in the target
416 qXfer:statictrace:read
418 Read the static trace data collected (by a `collect $_sdata'
419 tracepoint action). The remote stub reports support for this packet
420 to gdb's qSupported query.
424 Send the current settings of GDB's permission flags.
428 Send part of the source (textual) form of a tracepoint definition,
429 which includes location, conditional, and action list.
431 * The source command now accepts a -s option to force searching for the
432 script in the source search path even if the script name specifies
435 * New features in the GDB remote stub, GDBserver
437 - GDBserver now support tracepoints (including fast tracepoints, and
438 static tracepoints). The feature is currently supported by the
439 i386-linux and amd64-linux builds. See the "Tracepoints support
440 in gdbserver" section in the manual for more information.
442 GDBserver JIT compiles the tracepoint's conditional agent
443 expression bytecode into native code whenever possible for low
444 overhead dynamic tracepoints conditionals. For such tracepoints,
445 an expression that examines program state is evaluated when the
446 tracepoint is reached, in order to determine whether to capture
447 trace data. If the condition is simple and false, processing the
448 tracepoint finishes very quickly and no data is gathered.
450 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
451 for static tracepoints support.
453 - GDBserver now supports x86_64 Windows 64-bit debugging.
455 * GDB now sends xmlRegisters= in qSupported packet to indicate that
456 it understands register description.
458 * The --batch flag now disables pagination and queries.
460 * X86 general purpose registers
462 GDB now supports reading/writing byte, word and double-word x86
463 general purpose registers directly. This means you can use, say,
464 $ah or $ax to refer, respectively, to the byte register AH and
465 16-bit word register AX that are actually portions of the 32-bit
466 register EAX or 64-bit register RAX.
468 * The `commands' command now accepts a range of breakpoints to modify.
469 A plain `commands' following a command that creates multiple
470 breakpoints affects all the breakpoints set by that command. This
471 applies to breakpoints set by `rbreak', and also applies when a
472 single `break' command creates multiple breakpoints (e.g.,
473 breakpoints on overloaded c++ functions).
475 * The `rbreak' command now accepts a filename specification as part of
476 its argument, limiting the functions selected by the regex to those
477 in the specified file.
479 * Support for remote debugging Windows and SymbianOS shared libraries
480 from Unix hosts has been improved. Non Windows GDB builds now can
481 understand target reported file names that follow MS-DOS based file
482 system semantics, such as file names that include drive letters and
483 use the backslash character as directory separator. This makes it
484 possible to transparently use the "set sysroot" and "set
485 solib-search-path" on Unix hosts to point as host copies of the
486 target's shared libraries. See the new command "set
487 target-file-system-kind" described below, and the "Commands to
488 specify files" section in the user manual for more information.
492 eval template, expressions...
493 Convert the values of one or more expressions under the control
494 of the string template to a command line, and call it.
496 set target-file-system-kind unix|dos-based|auto
497 show target-file-system-kind
498 Set or show the assumed file system kind for target reported file
501 save breakpoints <filename>
502 Save all current breakpoint definitions to a file suitable for use
503 in a later debugging session. To read the saved breakpoint
504 definitions, use the `source' command.
506 `save tracepoints' is a new alias for `save-tracepoints'. The latter
509 info static-tracepoint-markers
510 Display information about static tracepoint markers in the target.
512 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
513 Define a static tracepoint by probing a marker at the given
514 function, line, address, or marker ID.
518 Enable and disable observer mode.
520 set may-write-registers on|off
521 set may-write-memory on|off
522 set may-insert-breakpoints on|off
523 set may-insert-tracepoints on|off
524 set may-insert-fast-tracepoints on|off
525 set may-interrupt on|off
526 Set individual permissions for GDB effects on the target. Note that
527 some of these settings can have undesirable or surprising
528 consequences, particularly when changed in the middle of a session.
529 For instance, disabling the writing of memory can prevent
530 breakpoints from being inserted, cause single-stepping to fail, or
531 even crash your program, if you disable after breakpoints have been
532 inserted. However, GDB should not crash.
534 set record memory-query on|off
535 show record memory-query
536 Control whether to stop the inferior if memory changes caused
537 by an instruction cannot be recorded.
542 The disassemble command now supports "start,+length" form of two arguments.
546 ** GDB now provides a new directory location, called the python directory,
547 where Python scripts written for GDB can be installed. The location
548 of that directory is <data-directory>/python, where <data-directory>
549 is the GDB data directory. For more details, see section `Scripting
550 GDB using Python' in the manual.
552 ** The GDB Python API now has access to breakpoints, symbols, symbol
553 tables, program spaces, inferiors, threads and frame's code blocks.
554 Additionally, GDB Parameters can now be created from the API, and
555 manipulated via set/show in the CLI.
557 ** New functions gdb.target_charset, gdb.target_wide_charset,
558 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
560 ** New exception gdb.GdbError.
562 ** Pretty-printers are now also looked up in the current program space.
564 ** Pretty-printers can now be individually enabled and disabled.
566 ** GDB now looks for names of Python scripts to auto-load in a
567 special section named `.debug_gdb_scripts', in addition to looking
568 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
570 * Tracepoint actions were unified with breakpoint commands. In particular,
571 there are no longer differences in "info break" output for breakpoints and
572 tracepoints and the "commands" command can be used for both tracepoints and
577 ARM Symbian arm*-*-symbianelf*
579 * D language support.
580 GDB now supports debugging programs written in the D programming
583 * GDB now supports the extended ptrace interface for PowerPC which is
584 available since Linux kernel version 2.6.34. This automatically enables
585 any hardware breakpoints and additional hardware watchpoints available in
586 the processor. The old ptrace interface exposes just one hardware
587 watchpoint and no hardware breakpoints.
589 * GDB is now able to use the Data Value Compare (DVC) register available on
590 embedded PowerPC processors to implement in hardware simple watchpoint
591 conditions of the form:
593 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
595 This works in native GDB running on Linux kernels with the extended ptrace
596 interface mentioned above.
598 *** Changes in GDB 7.1
604 GDB now supports importing of namespaces in C++. This enables the
605 user to inspect variables from imported namespaces. Support for
606 namepace aliasing has also been added. So, if a namespace is
607 aliased in the current scope (e.g. namepace C=A; ) the user can
608 print variables using the alias (e.g. (gdb) print C::x).
612 All known bugs relating to the printing of virtual base class were
613 fixed. It is now possible to call overloaded static methods using a
618 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
619 and reinterpret_cast<> are now handled by the C++ expression parser.
623 Xilinx MicroBlaze microblaze-*-*
628 Xilinx MicroBlaze microblaze
631 * Multi-program debugging.
633 GDB now has support for multi-program (a.k.a. multi-executable or
634 multi-exec) debugging. This allows for debugging multiple inferiors
635 simultaneously each running a different program under the same GDB
636 session. See "Debugging Multiple Inferiors and Programs" in the
637 manual for more information. This implied some user visible changes
638 in the multi-inferior support. For example, "info inferiors" now
639 lists inferiors that are not running yet or that have exited
640 already. See also "New commands" and "New options" below.
642 * New tracing features
644 GDB's tracepoint facility now includes several new features:
646 ** Trace state variables
648 GDB tracepoints now include support for trace state variables, which
649 are variables managed by the target agent during a tracing
650 experiment. They are useful for tracepoints that trigger each
651 other, so for instance one tracepoint can count hits in a variable,
652 and then a second tracepoint has a condition that is true when the
653 count reaches a particular value. Trace state variables share the
654 $-syntax of GDB convenience variables, and can appear in both
655 tracepoint actions and condition expressions. Use the "tvariable"
656 command to create, and "info tvariables" to view; see "Trace State
657 Variables" in the manual for more detail.
661 GDB now includes an option for defining fast tracepoints, which
662 targets may implement more efficiently, such as by installing a jump
663 into the target agent rather than a trap instruction. The resulting
664 speedup can be by two orders of magnitude or more, although the
665 tradeoff is that some program locations on some target architectures
666 might not allow fast tracepoint installation, for instance if the
667 instruction to be replaced is shorter than the jump. To request a
668 fast tracepoint, use the "ftrace" command, with syntax identical to
669 the regular trace command.
671 ** Disconnected tracing
673 It is now possible to detach GDB from the target while it is running
674 a trace experiment, then reconnect later to see how the experiment
675 is going. In addition, a new variable disconnected-tracing lets you
676 tell the target agent whether to continue running a trace if the
677 connection is lost unexpectedly.
681 GDB now has the ability to save the trace buffer into a file, and
682 then use that file as a target, similarly to you can do with
683 corefiles. You can select trace frames, print data that was
684 collected in them, and use tstatus to display the state of the
685 tracing run at the moment that it was saved. To create a trace
686 file, use "tsave <filename>", and to use it, do "target tfile
689 ** Circular trace buffer
691 You can ask the target agent to handle the trace buffer as a
692 circular buffer, discarding the oldest trace frames to make room for
693 newer ones, by setting circular-trace-buffer to on. This feature may
694 not be available for all target agents.
699 The disassemble command, when invoked with two arguments, now requires
700 the arguments to be comma-separated.
703 The info variables command now displays variable definitions. Files
704 which only declare a variable are not shown.
707 The source command is now capable of sourcing Python scripts.
708 This feature is dependent on the debugger being build with Python
711 Related to this enhancement is also the introduction of a new command
712 "set script-extension" (see below).
714 * New commands (for set/show, see "New options" below)
716 record save [<FILENAME>]
717 Save a file (in core file format) containing the process record
718 execution log for replay debugging at a later time.
720 record restore <FILENAME>
721 Restore the process record execution log that was saved at an
722 earlier time, for replay debugging.
724 add-inferior [-copies <N>] [-exec <FILENAME>]
727 clone-inferior [-copies <N>] [ID]
728 Make a new inferior ready to execute the same program another
734 maint info program-spaces
735 List the program spaces loaded into GDB.
737 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
738 show remote interrupt-sequence
739 Allow the user to select one of ^C, a BREAK signal or BREAK-g
740 as the sequence to the remote target in order to interrupt the execution.
741 Ctrl-C is a default. Some system prefers BREAK which is high level of
742 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
743 Magic SysRq g. It is BREAK signal and character 'g'.
745 set remote interrupt-on-connect [on | off]
746 show remote interrupt-on-connect
747 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
748 remote target when gdb connects to it. This is needed when you debug
751 set remotebreak [on | off]
753 Deprecated. Use "set/show remote interrupt-sequence" instead.
755 tvariable $NAME [ = EXP ]
756 Create or modify a trace state variable.
759 List trace state variables and their values.
761 delete tvariable $NAME ...
762 Delete one or more trace state variables.
765 Evaluate the given expressions without collecting anything into the
766 trace buffer. (Valid in tracepoint actions only.)
768 ftrace FN / FILE:LINE / *ADDR
769 Define a fast tracepoint at the given function, line, or address.
771 * New expression syntax
773 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
774 GDB now parses 0b101010 identically with 42.
778 set follow-exec-mode new|same
779 show follow-exec-mode
780 Control whether GDB reuses the same inferior across an exec call or
781 creates a new one. This is useful to be able to restart the old
782 executable after the inferior having done an exec call.
784 set default-collect EXPR, ...
786 Define a list of expressions to be collected at each tracepoint.
787 This is a useful way to ensure essential items are not overlooked,
788 such as registers or a critical global variable.
790 set disconnected-tracing
791 show disconnected-tracing
792 If set to 1, the target is instructed to continue tracing if it
793 loses its connection to GDB. If 0, the target is to stop tracing
796 set circular-trace-buffer
797 show circular-trace-buffer
798 If set to on, the target is instructed to use a circular trace buffer
799 and discard the oldest trace frames instead of stopping the trace due
800 to a full trace buffer. If set to off, the trace stops when the buffer
801 fills up. Some targets may not support this.
803 set script-extension off|soft|strict
804 show script-extension
805 If set to "off", the debugger does not perform any script language
806 recognition, and all sourced files are assumed to be GDB scripts.
807 If set to "soft" (the default), files are sourced according to
808 filename extension, falling back to GDB scripts if the first
810 If set to "strict", files are sourced according to filename extension.
812 set ada trust-PAD-over-XVS on|off
813 show ada trust-PAD-over-XVS
814 If off, activate a workaround against a bug in the debugging information
815 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
816 the GCC sources for more information about the GNAT encoding and
817 PAD types in particular). It is always safe to set this option to
818 off, but this introduces a slight performance penalty. The default
821 * Python API Improvements
823 ** GDB provides the new class gdb.LazyString. This is useful in
824 some pretty-printing cases. The new method gdb.Value.lazy_string
825 provides a simple way to create objects of this type.
827 ** The fields returned by gdb.Type.fields now have an
828 `is_base_class' attribute.
830 ** The new method gdb.Type.range returns the range of an array type.
832 ** The new method gdb.parse_and_eval can be used to parse and
833 evaluate an expression.
838 Define a trace state variable.
841 Get the current value of a trace state variable.
844 Set desired tracing behavior upon disconnection.
847 Set the trace buffer to be linear or circular.
850 Get data about the tracepoints currently in use.
854 Process record now works correctly with hardware watchpoints.
856 Multiple bug fixes have been made to the mips-irix port, making it
857 much more reliable. In particular:
858 - Debugging threaded applications is now possible again. Previously,
859 GDB would hang while starting the program, or while waiting for
860 the program to stop at a breakpoint.
861 - Attaching to a running process no longer hangs.
862 - An error occurring while loading a core file has been fixed.
863 - Changing the value of the PC register now works again. This fixes
864 problems observed when using the "jump" command, or when calling
865 a function from GDB, or even when assigning a new value to $pc.
866 - With the "finish" and "return" commands, the return value for functions
867 returning a small array is now correctly printed.
868 - It is now possible to break on shared library code which gets executed
869 during a shared library init phase (code executed while executing
870 their .init section). Previously, the breakpoint would have no effect.
871 - GDB is now able to backtrace through the signal handler for
872 non-threaded programs.
874 PIE (Position Independent Executable) programs debugging is now supported.
875 This includes debugging execution of PIC (Position Independent Code) shared
876 libraries although for that, it should be possible to run such libraries as an
879 *** Changes in GDB 7.0
881 * GDB now has an interface for JIT compilation. Applications that
882 dynamically generate code can create symbol files in memory and register
883 them with GDB. For users, the feature should work transparently, and
884 for JIT developers, the interface is documented in the GDB manual in the
885 "JIT Compilation Interface" chapter.
887 * Tracepoints may now be conditional. The syntax is as for
888 breakpoints; either an "if" clause appended to the "trace" command,
889 or the "condition" command is available. GDB sends the condition to
890 the target for evaluation using the same bytecode format as is used
891 for tracepoint actions.
893 * The disassemble command now supports: an optional /r modifier, print the
894 raw instructions in hex as well as in symbolic form, and an optional /m
895 modifier to print mixed source+assembly.
897 * Process record and replay
899 In a architecture environment that supports ``process record and
900 replay'', ``process record and replay'' target can record a log of
901 the process execution, and replay it with both forward and reverse
904 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
905 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
906 set execution-direction {forward|reverse}, for targets that support
909 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
910 feature is available with a native GDB running on kernel version
913 * GDB now has support for multi-byte and wide character sets on the
914 target. Strings whose character type is wchar_t, char16_t, or
915 char32_t are now correctly printed. GDB supports wide- and unicode-
916 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
917 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
918 `printf'. This feature requires iconv to work properly; if your
919 system does not have a working iconv, GDB can use GNU libiconv. See
920 the installation instructions for more information.
922 * GDB now supports automatic retrieval of shared library files from
923 remote targets. To use this feature, specify a system root that begins
924 with the `remote:' prefix, either via the `set sysroot' command or via
925 the `--with-sysroot' configure-time option.
927 * "info sharedlibrary" now takes an optional regex of libraries to show,
928 and it now reports if a shared library has no debugging information.
930 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
931 now complete on file names.
933 * When completing in expressions, gdb will attempt to limit
934 completions to allowable structure or union fields, where appropriate.
935 For instance, consider:
937 # struct example { int f1; double f2; };
938 # struct example variable;
941 If the user types TAB at the end of this command line, the available
942 completions will be "f1" and "f2".
944 * Inlined functions are now supported. They show up in backtraces, and
945 the "step", "next", and "finish" commands handle them automatically.
947 * GDB now supports the token-splicing (##) and stringification (#)
948 operators when expanding macros. It also supports variable-arity
951 * GDB now supports inspecting extra signal information, exported by
952 the new $_siginfo convenience variable. The feature is currently
953 implemented on linux ARM, i386 and amd64.
955 * GDB can now display the VFP floating point registers and NEON vector
956 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
957 can provide these registers (requires Linux 2.6.30 or later). Remote
958 and simulator targets may also provide them.
963 Search memory for a sequence of bytes.
966 Turn off `+'/`-' protocol acknowledgments to permit more efficient
967 operation over reliable transport links. Use of this packet is
968 controlled by the `set remote noack-packet' command.
971 Kill the process with the specified process ID. Use this in preference
972 to `k' when multiprocess protocol extensions are supported.
975 Obtains additional operating system information
979 Read or write additional signal information.
981 * Removed remote protocol undocumented extension
983 An undocumented extension to the remote protocol's `S' stop reply
984 packet that permited the stub to pass a process id was removed.
985 Remote servers should use the `T' stop reply packet instead.
987 * GDB now supports multiple function calling conventions according to the
988 DWARF-2 DW_AT_calling_convention function attribute.
990 * The SH target utilizes the aforementioned change to distinguish between gcc
991 and Renesas calling convention. It also adds the new CLI commands
992 `set/show sh calling-convention'.
994 * GDB can now read compressed debug sections, as produced by GNU gold
995 with the --compress-debug-sections=zlib flag.
997 * 64-bit core files are now supported on AIX.
999 * Thread switching is now supported on Tru64.
1001 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1002 which will be allocated using malloc later in program execution.
1004 * The qXfer:libraries:read remote procotol packet now allows passing a
1005 list of section offsets.
1007 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1008 conditions handling signals delivered during attach or thread creation
1009 have also been fixed.
1011 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1012 From the user's standpoint, all unqualified instances of True and False
1013 are treated as the standard definitions, regardless of context.
1015 * GDB now parses C++ symbol and type names more flexibly. For
1018 template<typename T> class C { };
1021 GDB will now correctly handle all of:
1023 ptype C<char const *>
1024 ptype C<char const*>
1025 ptype C<const char *>
1026 ptype C<const char*>
1028 * New features in the GDB remote stub, gdbserver
1030 - The "--wrapper" command-line argument tells gdbserver to use a
1031 wrapper program to launch programs for debugging.
1033 - On PowerPC and S/390 targets, it is now possible to use a single
1034 gdbserver executable to debug both 32-bit and 64-bit programs.
1035 (This requires gdbserver itself to be built as a 64-bit executable.)
1037 - gdbserver uses the new noack protocol mode for TCP connections to
1038 reduce communications latency, if also supported and enabled in GDB.
1040 - Support for the sparc64-linux-gnu target is now included in
1043 - The amd64-linux build of gdbserver now supports debugging both
1044 32-bit and 64-bit programs.
1046 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1047 now support hardware watchpoints, and will use them automatically
1052 GDB now has support for scripting using Python. Whether this is
1053 available is determined at configure time.
1055 New GDB commands can now be written in Python.
1057 * Ada tasking support
1059 Ada tasks can now be inspected in GDB. The following commands have
1063 Print the list of Ada tasks.
1065 Print detailed information about task number N.
1067 Print the task number of the current task.
1069 Switch the context of debugging to task number N.
1071 * Support for user-defined prefixed commands. The "define" command can
1072 add new commands to existing prefixes, e.g. "target".
1074 * Multi-inferior, multi-process debugging.
1076 GDB now has generalized support for multi-inferior debugging. See
1077 "Debugging Multiple Inferiors" in the manual for more information.
1078 Although availability still depends on target support, the command
1079 set is more uniform now. The GNU/Linux specific multi-forks support
1080 has been migrated to this new framework. This implied some user
1081 visible changes; see "New commands" and also "Removed commands"
1084 * Target descriptions can now describe the target OS ABI. See the
1085 "Target Description Format" section in the user manual for more
1088 * Target descriptions can now describe "compatible" architectures
1089 to indicate that the target can execute applications for a different
1090 architecture in addition to those for the main target architecture.
1091 See the "Target Description Format" section in the user manual for
1094 * Multi-architecture debugging.
1096 GDB now includes general supports for debugging applications on
1097 hybrid systems that use more than one single processor architecture
1098 at the same time. Each such hybrid architecture still requires
1099 specific support to be added. The only hybrid architecture supported
1100 in this version of GDB is the Cell Broadband Engine.
1102 * GDB now supports integrated debugging of Cell/B.E. applications that
1103 use both the PPU and SPU architectures. To enable support for hybrid
1104 Cell/B.E. debugging, you need to configure GDB to support both the
1105 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1106 --enable-targets configure option.
1108 * Non-stop mode debugging.
1110 For some targets, GDB now supports an optional mode of operation in
1111 which you can examine stopped threads while other threads continue
1112 to execute freely. This is referred to as non-stop mode, with the
1113 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1114 section in the user manual for more information.
1116 To be able to support remote non-stop debugging, a remote stub needs
1117 to implement the non-stop mode remote protocol extensions, as
1118 described in the "Remote Non-Stop" section of the user manual. The
1119 GDB remote stub, gdbserver, has been adjusted to support these
1120 extensions on linux targets.
1122 * New commands (for set/show, see "New options" below)
1124 catch syscall [NAME(S) | NUMBER(S)]
1125 Catch system calls. Arguments, which should be names of system
1126 calls or their numbers, mean catch only those syscalls. Without
1127 arguments, every syscall will be caught. When the inferior issues
1128 any of the specified syscalls, GDB will stop and announce the system
1129 call, both when it is called and when its call returns. This
1130 feature is currently available with a native GDB running on the
1131 Linux Kernel, under the following architectures: x86, x86_64,
1132 PowerPC and PowerPC64.
1134 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1136 Search memory for a sequence of bytes.
1138 maint set python print-stack
1139 maint show python print-stack
1140 Show a stack trace when an error is encountered in a Python script.
1143 Invoke CODE by passing it to the Python interpreter.
1148 These allow macros to be defined, undefined, and listed
1152 Show operating system information about processes.
1155 List the inferiors currently under GDB's control.
1158 Switch focus to inferior number NUM.
1161 Detach from inferior number NUM.
1164 Kill inferior number NUM.
1168 set spu stop-on-load
1169 show spu stop-on-load
1170 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1172 set spu auto-flush-cache
1173 show spu auto-flush-cache
1174 Control whether to automatically flush the software-managed cache
1175 during Cell/B.E. debugging.
1177 set sh calling-convention
1178 show sh calling-convention
1179 Control the calling convention used when calling SH target functions.
1182 show debug timestamp
1183 Control display of timestamps with GDB debugging output.
1185 set disassemble-next-line
1186 show disassemble-next-line
1187 Control display of disassembled source lines or instructions when
1190 set remote noack-packet
1191 show remote noack-packet
1192 Set/show the use of remote protocol QStartNoAckMode packet. See above
1193 under "New remote packets."
1195 set remote query-attached-packet
1196 show remote query-attached-packet
1197 Control use of remote protocol `qAttached' (query-attached) packet.
1199 set remote read-siginfo-object
1200 show remote read-siginfo-object
1201 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1204 set remote write-siginfo-object
1205 show remote write-siginfo-object
1206 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1209 set remote reverse-continue
1210 show remote reverse-continue
1211 Control use of remote protocol 'bc' (reverse-continue) packet.
1213 set remote reverse-step
1214 show remote reverse-step
1215 Control use of remote protocol 'bs' (reverse-step) packet.
1217 set displaced-stepping
1218 show displaced-stepping
1219 Control displaced stepping mode. Displaced stepping is a way to
1220 single-step over breakpoints without removing them from the debuggee.
1221 Also known as "out-of-line single-stepping".
1224 show debug displaced
1225 Control display of debugging info for displaced stepping.
1227 maint set internal-error
1228 maint show internal-error
1229 Control what GDB does when an internal error is detected.
1231 maint set internal-warning
1232 maint show internal-warning
1233 Control what GDB does when an internal warning is detected.
1238 Use a wrapper program to launch programs for debugging.
1240 set multiple-symbols (all|ask|cancel)
1241 show multiple-symbols
1242 The value of this variable can be changed to adjust the debugger behavior
1243 when an expression or a breakpoint location contains an ambiguous symbol
1244 name (an overloaded function name, for instance).
1246 set breakpoint always-inserted
1247 show breakpoint always-inserted
1248 Keep breakpoints always inserted in the target, as opposed to inserting
1249 them when resuming the target, and removing them when the target stops.
1250 This option can improve debugger performance on slow remote targets.
1252 set arm fallback-mode (arm|thumb|auto)
1253 show arm fallback-mode
1254 set arm force-mode (arm|thumb|auto)
1256 These commands control how ARM GDB determines whether instructions
1257 are ARM or Thumb. The default for both settings is auto, which uses
1258 the current CPSR value for instructions without symbols; previous
1259 versions of GDB behaved as if "set arm fallback-mode arm".
1261 set disable-randomization
1262 show disable-randomization
1263 Standalone programs run with the virtual address space randomization enabled
1264 by default on some platforms. This option keeps the addresses stable across
1265 multiple debugging sessions.
1269 Control whether other threads are stopped or not when some thread hits
1274 Requests that asynchronous execution is enabled in the target, if available.
1275 In this case, it's possible to resume target in the background, and interact
1276 with GDB while the target is running. "show target-async" displays the
1277 current state of asynchronous execution of the target.
1279 set target-wide-charset
1280 show target-wide-charset
1281 The target-wide-charset is the name of the character set that GDB
1282 uses when printing characters whose type is wchar_t.
1284 set tcp auto-retry (on|off)
1286 set tcp connect-timeout
1287 show tcp connect-timeout
1288 These commands allow GDB to retry failed TCP connections to a remote stub
1289 with a specified timeout period; this is useful if the stub is launched
1290 in parallel with GDB but may not be ready to accept connections immediately.
1292 set libthread-db-search-path
1293 show libthread-db-search-path
1294 Control list of directories which GDB will search for appropriate
1297 set schedule-multiple (on|off)
1298 show schedule-multiple
1299 Allow GDB to resume all threads of all processes or only threads of
1300 the current process.
1304 Use more aggressive caching for accesses to the stack. This improves
1305 performance of remote debugging (particularly backtraces) without
1306 affecting correctness.
1308 set interactive-mode (on|off|auto)
1309 show interactive-mode
1310 Control whether GDB runs in interactive mode (on) or not (off).
1311 When in interactive mode, GDB waits for the user to answer all
1312 queries. Otherwise, GDB does not wait and assumes the default
1313 answer. When set to auto (the default), GDB determines which
1314 mode to use based on the stdin settings.
1319 For program forks, this is replaced by the new more generic `info
1320 inferiors' command. To list checkpoints, you can still use the
1321 `info checkpoints' command, which was an alias for the `info forks'
1325 Replaced by the new `inferior' command. To switch between
1326 checkpoints, you can still use the `restart' command, which was an
1327 alias for the `fork' command.
1330 This is removed, since some targets don't have a notion of
1331 processes. To switch between processes, you can still use the
1332 `inferior' command using GDB's own inferior number.
1335 For program forks, this is replaced by the new more generic `kill
1336 inferior' command. To delete a checkpoint, you can still use the
1337 `delete checkpoint' command, which was an alias for the `delete
1341 For program forks, this is replaced by the new more generic `detach
1342 inferior' command. To detach a checkpoint, you can still use the
1343 `detach checkpoint' command, which was an alias for the `detach
1346 * New native configurations
1348 x86/x86_64 Darwin i[34567]86-*-darwin*
1350 x86_64 MinGW x86_64-*-mingw*
1354 Lattice Mico32 lm32-*
1355 x86 DICOS i[34567]86-*-dicos*
1356 x86_64 DICOS x86_64-*-dicos*
1359 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1360 (mingw32ce) debugging.
1366 These commands were actually not implemented on any target.
1368 *** Changes in GDB 6.8
1370 * New native configurations
1372 NetBSD/hppa hppa*-*netbsd*
1373 Xtensa GNU/Linux xtensa*-*-linux*
1377 NetBSD/hppa hppa*-*-netbsd*
1378 Xtensa GNU/Lunux xtensa*-*-linux*
1380 * Change in command line behavior -- corefiles vs. process ids.
1382 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1383 attaching to process NUMBER fails, GDB no longer attempts to open a
1384 core file named NUMBER. Attaching to a program using the -c option
1385 is no longer supported. Instead, use the '-p' or '--pid' options.
1387 * GDB can now be built as a native debugger for debugging Windows x86
1388 (mingw32) Portable Executable (PE) programs.
1390 * Pending breakpoints no longer change their number when their address
1393 * GDB now supports breakpoints with multiple locations,
1394 including breakpoints on C++ constructors, inside C++ templates,
1395 and in inlined functions.
1397 * GDB's ability to debug optimized code has been improved. GDB more
1398 accurately identifies function bodies and lexical blocks that occupy
1399 more than one contiguous range of addresses.
1401 * Target descriptions can now describe registers for PowerPC.
1403 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1404 registers on PowerPC targets.
1406 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1407 targets even when the libthread_db library is not available.
1409 * The GDB remote stub, gdbserver, now supports the new file transfer
1410 commands (remote put, remote get, and remote delete).
1412 * The GDB remote stub, gdbserver, now supports run and attach in
1413 extended-remote mode.
1415 * hppa*64*-*-hpux11* target broken
1416 The debugger is unable to start a program and fails with the following
1417 error: "Error trying to get information about dynamic linker".
1418 The gdb-6.7 release is also affected.
1420 * GDB now supports the --enable-targets= configure option to allow
1421 building a single GDB executable that supports multiple remote
1422 target architectures.
1424 * GDB now supports debugging C and C++ programs which use the
1425 Decimal Floating Point extension. In addition, the PowerPC target
1426 now has a set of pseudo-registers to inspect decimal float values
1427 stored in two consecutive float registers.
1429 * The -break-insert MI command can optionally create pending
1432 * Improved support for debugging Ada
1433 Many improvements to the Ada language support have been made. These
1435 - Better support for Ada2005 interface types
1436 - Improved handling of arrays and slices in general
1437 - Better support for Taft-amendment types
1438 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1440 - Improved command completion in Ada
1443 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1448 set print frame-arguments (all|scalars|none)
1449 show print frame-arguments
1450 The value of this variable can be changed to control which argument
1451 values should be printed by the debugger when displaying a frame.
1456 Transfer files to and from a remote target, and delete remote files.
1463 Transfer files to and from a remote target, and delete remote files.
1465 * New remote packets
1472 Open, close, read, write, and delete files on the remote system.
1475 Attach to an existing process on the remote system, in extended-remote
1479 Run a new process on the remote system, in extended-remote mode.
1481 *** Changes in GDB 6.7
1483 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1484 bfd, libiberty and opcodes, as revealed by static analysis donated by
1485 Coverity, Inc. (http://scan.coverity.com).
1487 * When looking up multiply-defined global symbols, GDB will now prefer the
1488 symbol definition in the current shared library if it was built using the
1489 -Bsymbolic linker option.
1491 * When the Text User Interface (TUI) is not configured, GDB will now
1492 recognize the -tui command-line option and print a message that the TUI
1495 * The GDB remote stub, gdbserver, now has lower overhead for high
1496 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1498 * GDB for MIPS targets now autodetects whether a remote target provides
1499 32-bit or 64-bit register values.
1501 * Support for C++ member pointers has been improved.
1503 * GDB now understands XML target descriptions, which specify the
1504 target's overall architecture. GDB can read a description from
1505 a local file or over the remote serial protocol.
1507 * Vectors of single-byte data use a new integer type which is not
1508 automatically displayed as character or string data.
1510 * The /s format now works with the print command. It displays
1511 arrays of single-byte integers and pointers to single-byte integers
1514 * Target descriptions can now describe target-specific registers,
1515 for architectures which have implemented the support (currently
1516 only ARM, M68K, and MIPS).
1518 * GDB and the GDB remote stub, gdbserver, now support the XScale
1521 * The GDB remote stub, gdbserver, has been updated to support
1522 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1523 has been rewritten to use the standard GDB remote protocol.
1525 * GDB can now step into C++ functions which are called through thunks.
1527 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1529 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1530 layout. It also supports a TextSeg= and DataSeg= response when only
1531 segment base addresses (rather than offsets) are available.
1533 * The /i format now outputs any trailing branch delay slot instructions
1534 immediately following the last instruction within the count specified.
1536 * The GDB remote protocol "T" stop reply packet now supports a
1537 "library" response. Combined with the new "qXfer:libraries:read"
1538 packet, this response allows GDB to debug shared libraries on targets
1539 where the operating system manages the list of loaded libraries (e.g.
1540 Windows and SymbianOS).
1542 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1543 (DLLs) on Windows and Windows CE targets.
1545 * GDB now supports a faster verification that a .debug file matches its binary
1546 according to its build-id signature, if the signature is present.
1552 Enable or disable hardware flow control (RTS/CTS) on the serial port
1553 when debugging using remote targets.
1555 set mem inaccessible-by-default
1556 show mem inaccessible-by-default
1557 If the target supplies a memory map, for instance via the remote
1558 protocol's "qXfer:memory-map:read" packet, setting this variable
1559 prevents GDB from accessing memory outside the memory map. This
1560 is useful for targets with memory mapped registers or which react
1561 badly to accesses of unmapped address space.
1563 set breakpoint auto-hw
1564 show breakpoint auto-hw
1565 If the target supplies a memory map, for instance via the remote
1566 protocol's "qXfer:memory-map:read" packet, setting this variable
1567 lets GDB use hardware breakpoints automatically for memory regions
1568 where it can not use software breakpoints. This covers both the
1569 "break" command and internal breakpoints used for other commands
1570 including "next" and "finish".
1573 catch exception unhandled
1574 Stop the program execution when Ada exceptions are raised.
1577 Stop the program execution when an Ada assertion failed.
1581 Set an alternate system root for target files. This is a more
1582 general version of "set solib-absolute-prefix", which is now
1583 an alias to "set sysroot".
1586 Provide extended SPU facility status information. This set of
1587 commands is available only when debugging the Cell/B.E. SPU
1590 * New native configurations
1592 OpenBSD/sh sh*-*openbsd*
1595 unset tdesc filename
1597 Use the specified local file as an XML target description, and do
1598 not query the target for its built-in description.
1602 OpenBSD/sh sh*-*-openbsd*
1603 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1604 Toshiba Media Processor mep-elf
1606 * New remote packets
1609 Ignore the specified signals; pass them directly to the debugged program
1610 without stopping other threads or reporting them to GDB.
1612 qXfer:features:read:
1613 Read an XML target description from the target, which describes its
1618 Read or write contents of an spufs file on the target system. These
1619 packets are available only on the Cell/B.E. SPU architecture.
1621 qXfer:libraries:read:
1622 Report the loaded shared libraries. Combined with new "T" packet
1623 response, this packet allows GDB to debug shared libraries on
1624 targets where the operating system manages the list of loaded
1625 libraries (e.g. Windows and SymbianOS).
1629 Support for these obsolete configurations has been removed.
1637 i[34567]86-*-lynxos*
1638 i[34567]86-*-netware*
1639 i[34567]86-*-sco3.2v5*
1640 i[34567]86-*-sco3.2v4*
1642 i[34567]86-*-sysv4.2*
1645 i[34567]86-*-unixware2*
1646 i[34567]86-*-unixware*
1655 * Other removed features
1662 Various m68k-only ROM monitors.
1669 Various Renesas ROM monitors and debugging interfaces for SH and
1674 Support for a Macraigor serial interface to on-chip debugging.
1675 GDB does not directly support the newer parallel or USB
1680 A debug information format. The predecessor to DWARF 2 and
1681 DWARF 3, which are still supported.
1683 Support for the HP aCC compiler on HP-UX/PA-RISC
1685 SOM-encapsulated symbolic debugging information, automatic
1686 invocation of pxdb, and the aCC custom C++ ABI. This does not
1687 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1688 with aCC can still be debugged on an assembly level.
1690 MIPS ".pdr" sections
1692 A MIPS-specific format used to describe stack frame layout
1693 in debugging information.
1697 GDB could work with an older version of Guile to debug
1698 the interpreter and Scheme programs running in it.
1700 set mips stack-arg-size
1701 set mips saved-gpreg-size
1703 Use "set mips abi" to control parameter passing for MIPS.
1705 *** Changes in GDB 6.6
1710 Cell Broadband Engine SPU spu-elf
1712 * GDB can now be configured as a cross-debugger targeting native Windows
1713 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1714 running on a Windows system over TCP/IP to debug Windows programs.
1716 * The GDB remote stub, gdbserver, has been updated to support Windows and
1717 Cygwin debugging. Both single-threaded and multi-threaded programs are
1720 * The "set trust-readonly-sections" command works again. This command was
1721 broken in GDB 6.3, 6.4, and 6.5.
1723 * The "load" command now supports writing to flash memory, if the remote
1724 stub provides the required support.
1726 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1727 longer requires symbolic debug information (e.g. DWARF-2).
1732 unset substitute-path
1733 show substitute-path
1734 Manage a list of substitution rules that GDB uses to rewrite the name
1735 of the directories where the sources are located. This can be useful
1736 for instance when the sources were moved to a different location
1737 between compilation and debugging.
1741 Print each CLI command as it is executed. Each command is prefixed with
1742 a number of `+' symbols representing the nesting depth.
1743 The source command now has a `-v' option to enable the same feature.
1747 The ARM Demon monitor support (RDP protocol, "target rdp").
1749 Kernel Object Display, an embedded debugging feature which only worked with
1750 an obsolete version of Cisco IOS.
1752 The 'set download-write-size' and 'show download-write-size' commands.
1754 * New remote packets
1757 Tell a stub about GDB client features, and request remote target features.
1758 The first feature implemented is PacketSize, which allows the target to
1759 specify the size of packets it can handle - to minimize the number of
1760 packets required and improve performance when connected to a remote
1764 Fetch an OS auxilliary vector from the remote stub. This packet is a
1765 more efficient replacement for qPart:auxv:read.
1767 qXfer:memory-map:read:
1768 Fetch a memory map from the remote stub, including information about
1769 RAM, ROM, and flash memory devices.
1774 Erase and program a flash memory device.
1776 * Removed remote packets
1779 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1780 used it, and only gdbserver implemented it.
1782 *** Changes in GDB 6.5
1786 Renesas M32C/M16C m32c-elf
1788 Morpho Technologies ms1 ms1-elf
1792 init-if-undefined Initialize a convenience variable, but
1793 only if it doesn't already have a value.
1795 The following commands are presently only implemented for native GNU/Linux:
1797 checkpoint Save a snapshot of the program state.
1799 restart <n> Return the program state to a
1800 previously saved state.
1802 info checkpoints List currently saved checkpoints.
1804 delete-checkpoint <n> Delete a previously saved checkpoint.
1806 set|show detach-on-fork Tell gdb whether to detach from a newly
1807 forked process, or to keep debugging it.
1809 info forks List forks of the user program that
1810 are available to be debugged.
1812 fork <n> Switch to debugging one of several
1813 forks of the user program that are
1814 available to be debugged.
1816 delete-fork <n> Delete a fork from the list of forks
1817 that are available to be debugged (and
1818 kill the forked process).
1820 detach-fork <n> Delete a fork from the list of forks
1821 that are available to be debugged (and
1822 allow the process to continue).
1826 Morpho Technologies ms2 ms1-elf
1828 * Improved Windows host support
1830 GDB now builds as a cross debugger hosted on i686-mingw32, including
1831 native console support, and remote communications using either
1832 network sockets or serial ports.
1834 * Improved Modula-2 language support
1836 GDB can now print most types in the Modula-2 syntax. This includes:
1837 basic types, set types, record types, enumerated types, range types,
1838 pointer types and ARRAY types. Procedure var parameters are correctly
1839 printed and hexadecimal addresses and character constants are also
1840 written in the Modula-2 syntax. Best results can be obtained by using
1841 GNU Modula-2 together with the -gdwarf-2 command line option.
1845 The ARM rdi-share module.
1847 The Netware NLM debug server.
1849 *** Changes in GDB 6.4
1851 * New native configurations
1853 OpenBSD/arm arm*-*-openbsd*
1854 OpenBSD/mips64 mips64-*-openbsd*
1858 Morpho Technologies ms1 ms1-elf
1860 * New command line options
1862 --batch-silent As for --batch, but totally silent.
1863 --return-child-result The debugger will exist with the same value
1864 the child (debugged) program exited with.
1865 --eval-command COMMAND, -ex COMMAND
1866 Execute a single GDB CLI command. This may be
1867 specified multiple times and in conjunction
1868 with the --command (-x) option.
1870 * Deprecated commands removed
1872 The following commands, that were deprecated in 2000, have been
1876 set|show arm disassembly-flavor set|show arm disassembler
1877 othernames set arm disassembler
1878 set|show remotedebug set|show debug remote
1879 set|show archdebug set|show debug arch
1880 set|show eventdebug set|show debug event
1883 * New BSD user-level threads support
1885 It is now possible to debug programs using the user-level threads
1886 library on OpenBSD and FreeBSD. Currently supported (target)
1889 FreeBSD/amd64 x86_64-*-freebsd*
1890 FreeBSD/i386 i386-*-freebsd*
1891 OpenBSD/i386 i386-*-openbsd*
1893 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1894 are not yet supported.
1896 * New support for Matsushita MN10300 w/sim added
1897 (Work in progress). mn10300-elf.
1899 * REMOVED configurations and files
1901 VxWorks and the XDR protocol *-*-vxworks
1902 Motorola MCORE mcore-*-*
1903 National Semiconductor NS32000 ns32k-*-*
1905 * New "set print array-indexes" command
1907 After turning this setting "on", GDB prints the index of each element
1908 when displaying arrays. The default is "off" to preserve the previous
1911 * VAX floating point support
1913 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1915 * User-defined command support
1917 In addition to using $arg0..$arg9 for argument passing, it is now possible
1918 to use $argc to determine now many arguments have been passed. See the
1919 section on user-defined commands in the user manual for more information.
1921 *** Changes in GDB 6.3:
1923 * New command line option
1925 GDB now accepts -l followed by a number to set the timeout for remote
1928 * GDB works with GCC -feliminate-dwarf2-dups
1930 GDB now supports a more compact representation of DWARF-2 debug
1931 information using DW_FORM_ref_addr references. These are produced
1932 by GCC with the option -feliminate-dwarf2-dups and also by some
1933 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1934 to use -feliminate-dwarf2-dups.
1936 * Internationalization
1938 When supported by the host system, GDB will be built with
1939 internationalization (libintl). The task of marking up the sources is
1940 continued, we're looking forward to our first translation.
1944 Initial support for debugging programs compiled with the GNAT
1945 implementation of the Ada programming language has been integrated
1946 into GDB. In this release, support is limited to expression evaluation.
1948 * New native configurations
1950 GNU/Linux/m32r m32r-*-linux-gnu
1954 GDB's remote protocol now includes support for the 'p' packet. This
1955 packet is used to fetch individual registers from a remote inferior.
1957 * END-OF-LIFE registers[] compatibility module
1959 GDB's internal register infrastructure has been completely rewritten.
1960 The new infrastructure making possible the implementation of key new
1961 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1964 GDB 6.3 will be the last release to include the the registers[]
1965 compatibility module that allowed out-of-date configurations to
1966 continue to work. This change directly impacts the following
1976 powerpc bdm protocol
1978 Unless there is activity to revive these configurations, they will be
1979 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1981 * OBSOLETE configurations and files
1983 Configurations that have been declared obsolete in this release have
1984 been commented out. Unless there is activity to revive these
1985 configurations, the next release of GDB will have their sources
1986 permanently REMOVED.
1995 *** Changes in GDB 6.2.1:
1997 * MIPS `break main; run' gave an heuristic-fence-post warning
1999 When attempting to run even a simple program, a warning about
2000 heuristic-fence-post being hit would be reported. This problem has
2003 * MIPS IRIX 'long double' crashed GDB
2005 When examining a long double variable, GDB would get a segmentation
2006 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2007 IRIX long double values).
2011 A bug in the VAX stack code was causing problems with the "next"
2012 command. This problem has been fixed.
2014 *** Changes in GDB 6.2:
2016 * Fix for ``many threads''
2018 On GNU/Linux systems that use the NPTL threads library, a program
2019 rapidly creating and deleting threads would confuse GDB leading to the
2022 ptrace: No such process.
2023 thread_db_get_info: cannot get thread info: generic error
2025 This problem has been fixed.
2027 * "-async" and "-noasync" options removed.
2029 Support for the broken "-noasync" option has been removed (it caused
2032 * New ``start'' command.
2034 This command runs the program until the begining of the main procedure.
2036 * New BSD Kernel Data Access Library (libkvm) interface
2038 Using ``target kvm'' it is now possible to debug kernel core dumps and
2039 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2040 platforms. Currently supported (native-only) configurations are:
2042 FreeBSD/amd64 x86_64-*-freebsd*
2043 FreeBSD/i386 i?86-*-freebsd*
2044 NetBSD/i386 i?86-*-netbsd*
2045 NetBSD/m68k m68*-*-netbsd*
2046 NetBSD/sparc sparc-*-netbsd*
2047 OpenBSD/amd64 x86_64-*-openbsd*
2048 OpenBSD/i386 i?86-*-openbsd*
2049 OpenBSD/m68k m68*-openbsd*
2050 OpenBSD/sparc sparc-*-openbsd*
2052 * Signal trampoline code overhauled
2054 Many generic problems with GDB's signal handling code have been fixed.
2055 These include: backtraces through non-contiguous stacks; recognition
2056 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2057 call; backtrace through a signal trampoline; step into and out of
2058 signal handlers; and single-stepping in the signal trampoline.
2060 Please note that kernel bugs are a limiting factor here. These
2061 features have been shown to work on an s390 GNU/Linux system that
2062 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2064 * Cygwin support for DWARF 2 added.
2066 * New native configurations
2068 GNU/Linux/hppa hppa*-*-linux*
2069 OpenBSD/hppa hppa*-*-openbsd*
2070 OpenBSD/m68k m68*-*-openbsd*
2071 OpenBSD/m88k m88*-*-openbsd*
2072 OpenBSD/powerpc powerpc-*-openbsd*
2073 NetBSD/vax vax-*-netbsd*
2074 OpenBSD/vax vax-*-openbsd*
2076 * END-OF-LIFE frame compatibility module
2078 GDB's internal frame infrastructure has been completely rewritten.
2079 The new infrastructure making it possible to support key new features
2080 including DWARF 2 Call Frame Information. To aid in the task of
2081 migrating old configurations to this new infrastructure, a
2082 compatibility module, that allowed old configurations to continue to
2083 work, was also included.
2085 GDB 6.2 will be the last release to include this frame compatibility
2086 module. This change directly impacts the following configurations:
2096 Unless there is activity to revive these configurations, they will be
2097 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2099 * REMOVED configurations and files
2101 Sun 3, running SunOS 3 m68*-*-sunos3*
2102 Sun 3, running SunOS 4 m68*-*-sunos4*
2103 Sun 2, running SunOS 3 m68000-*-sunos3*
2104 Sun 2, running SunOS 4 m68000-*-sunos4*
2105 Motorola 680x0 running LynxOS m68*-*-lynxos*
2106 AT&T 3b1/Unix pc m68*-att-*
2107 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2108 decstation mips-dec-* mips-little-*
2109 riscos mips-*-riscos* mips-*-sysv*
2110 sonymips mips-sony-*
2111 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2113 *** Changes in GDB 6.1.1:
2115 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2117 The TUI (Text-mode User Interface) is now built as part of a default
2118 GDB configuration. It is enabled by either selecting the TUI with the
2119 command line option "-i=tui" or by running the separate "gdbtui"
2120 program. For more information on the TUI, see the manual "Debugging
2123 * Pending breakpoint support (also included in GDB 6.1)
2125 Support has been added to allow you to specify breakpoints in shared
2126 libraries that have not yet been loaded. If a breakpoint location
2127 cannot be found, and the "breakpoint pending" option is set to auto,
2128 GDB queries you if you wish to make the breakpoint pending on a future
2129 shared-library load. If and when GDB resolves the breakpoint symbol,
2130 the pending breakpoint is removed as one or more regular breakpoints
2133 Pending breakpoints are very useful for GCJ Java debugging.
2135 * Fixed ISO-C build problems
2137 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2138 non ISO-C code that stopped them being built using a more strict ISO-C
2139 compiler (e.g., IBM's C compiler).
2141 * Fixed build problem on IRIX 5
2143 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2144 wasn't able to compile compile on an IRIX 5 system.
2146 * Added execute permission to gdb/gdbserver/configure
2148 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2149 permission. This bug would cause configure to fail on a number of
2150 systems (Solaris, IRIX). Ref: server/519.
2152 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2154 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2155 has been updated to use constant array sizes.
2157 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2159 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2160 its generated DWARF Call Frame Info. This encoding was causing GDB to
2161 panic, that panic has been fixed. Ref: gdb/1628.
2163 * Fixed a problem when examining parameters in shared library code.
2165 When examining parameters in optimized shared library code generated
2166 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2167 not available''. GDB now correctly displays the variable's value.
2169 *** Changes in GDB 6.1:
2171 * Removed --with-mmalloc
2173 Support for the mmalloc memory manager has been removed, as it
2174 conflicted with the internal gdb byte cache.
2176 * Changes in AMD64 configurations
2178 The AMD64 target now includes the %cs and %ss registers. As a result
2179 the AMD64 remote protocol has changed; this affects the floating-point
2180 and SSE registers. If you rely on those registers for your debugging,
2181 you should upgrade gdbserver on the remote side.
2183 * Revised SPARC target
2185 The SPARC target has been completely revised, incorporating the
2186 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2187 support for LynxOS and SunOS 4 has been dropped. Calling functions
2188 from within GDB on operating systems with a non-executable stack
2189 (Solaris, OpenBSD) now works.
2193 GDB has a new C++ demangler which does a better job on the mangled
2194 names generated by current versions of g++. It also runs faster, so
2195 with this and other changes gdb should now start faster on large C++
2198 * DWARF 2 Location Expressions
2200 GDB support for location expressions has been extended to support function
2201 arguments and frame bases. Older versions of GDB could crash when they
2204 * C++ nested types and namespaces
2206 GDB's support for nested types and namespaces in C++ has been
2207 improved, especially if you use the DWARF 2 debugging format. (This
2208 is the default for recent versions of GCC on most platforms.)
2209 Specifically, if you have a class "Inner" defined within a class or
2210 namespace "Outer", then GDB realizes that the class's name is
2211 "Outer::Inner", not simply "Inner". This should greatly reduce the
2212 frequency of complaints about not finding RTTI symbols. In addition,
2213 if you are stopped at inside of a function defined within a namespace,
2214 GDB modifies its name lookup accordingly.
2216 * New native configurations
2218 NetBSD/amd64 x86_64-*-netbsd*
2219 OpenBSD/amd64 x86_64-*-openbsd*
2220 OpenBSD/alpha alpha*-*-openbsd*
2221 OpenBSD/sparc sparc-*-openbsd*
2222 OpenBSD/sparc64 sparc64-*-openbsd*
2224 * New debugging protocols
2226 M32R with SDI protocol m32r-*-elf*
2228 * "set prompt-escape-char" command deleted.
2230 The command "set prompt-escape-char" has been deleted. This command,
2231 and its very obscure effet on GDB's prompt, was never documented,
2232 tested, nor mentioned in the NEWS file.
2234 * OBSOLETE configurations and files
2236 Configurations that have been declared obsolete in this release have
2237 been commented out. Unless there is activity to revive these
2238 configurations, the next release of GDB will have their sources
2239 permanently REMOVED.
2241 Sun 3, running SunOS 3 m68*-*-sunos3*
2242 Sun 3, running SunOS 4 m68*-*-sunos4*
2243 Sun 2, running SunOS 3 m68000-*-sunos3*
2244 Sun 2, running SunOS 4 m68000-*-sunos4*
2245 Motorola 680x0 running LynxOS m68*-*-lynxos*
2246 AT&T 3b1/Unix pc m68*-att-*
2247 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2248 decstation mips-dec-* mips-little-*
2249 riscos mips-*-riscos* mips-*-sysv*
2250 sonymips mips-sony-*
2251 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2253 * REMOVED configurations and files
2255 SGI Irix-4.x mips-sgi-irix4 or iris4
2256 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2257 Z8000 simulator z8k-zilog-none or z8ksim
2258 Matsushita MN10200 w/simulator mn10200-*-*
2259 H8/500 simulator h8500-hitachi-hms or h8500hms
2260 HP/PA running BSD hppa*-*-bsd*
2261 HP/PA running OSF/1 hppa*-*-osf*
2262 HP/PA Pro target hppa*-*-pro*
2263 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2264 386BSD i[3456]86-*-bsd*
2265 Sequent family i[3456]86-sequent-sysv4*
2266 i[3456]86-sequent-sysv*
2267 i[3456]86-sequent-bsd*
2268 SPARC running LynxOS sparc-*-lynxos*
2269 SPARC running SunOS 4 sparc-*-sunos4*
2270 Tsqware Sparclet sparclet-*-*
2271 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2273 *** Changes in GDB 6.0:
2277 Support for debugging the Objective-C programming language has been
2278 integrated into GDB.
2280 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2282 DWARF 2's Call Frame Information makes available compiler generated
2283 information that more exactly describes the program's run-time stack.
2284 By using this information, GDB is able to provide more robust stack
2287 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2288 have been updated to use a new backtrace mechanism which includes
2289 DWARF 2 CFI support.
2293 GDB's remote protocol has been extended to include support for hosted
2294 file I/O (where the remote target uses GDB's file system). See GDB's
2295 remote protocol documentation for details.
2297 * All targets using the new architecture framework.
2299 All of GDB's targets have been updated to use the new internal
2300 architecture framework. The way is now open for future GDB releases
2301 to include cross-architecture native debugging support (i386 on amd64,
2304 * GNU/Linux's Thread Local Storage (TLS)
2306 GDB now includes support for for the GNU/Linux implementation of
2307 per-thread variables.
2309 * GNU/Linux's Native POSIX Thread Library (NPTL)
2311 GDB's thread code has been updated to work with either the new
2312 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2314 * Separate debug info.
2316 GDB, in conjunction with BINUTILS, now supports a mechanism for
2317 automatically loading debug information from a separate file. Instead
2318 of shipping full debug and non-debug versions of system libraries,
2319 system integrators can now instead ship just the stripped libraries
2320 and optional debug files.
2322 * DWARF 2 Location Expressions
2324 DWARF 2 Location Expressions allow the compiler to more completely
2325 describe the location of variables (even in optimized code) to the
2328 GDB now includes preliminary support for location expressions (support
2329 for DW_OP_piece is still missing).
2333 A number of long standing bugs that caused GDB to die while starting a
2334 Java application have been fixed. GDB's Java support is now
2335 considered "useable".
2337 * GNU/Linux support for fork, vfork, and exec.
2339 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2340 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2343 * GDB supports logging output to a file
2345 There are two new commands, "set logging" and "show logging", which can be
2346 used to capture GDB's output to a file.
2348 * The meaning of "detach" has changed for gdbserver
2350 The "detach" command will now resume the application, as documented. To
2351 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2354 * d10v, m68hc11 `regs' command deprecated
2356 The `info registers' command has been updated so that it displays the
2357 registers using a format identical to the old `regs' command.
2361 A new command, "maint set profile on/off", has been added. This command can
2362 be used to enable or disable profiling while running GDB, to profile a
2363 session or a set of commands. In addition there is a new configure switch,
2364 "--enable-profiling", which will cause GDB to be compiled with profiling
2365 data, for more informative profiling results.
2367 * Default MI syntax changed to "mi2".
2369 The default MI (machine interface) syntax, enabled by the command line
2370 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2371 "mi1", can be enabled by specifying the option "-i=mi1".
2373 Support for the original "mi0" syntax (included in GDB 5.0) has been
2376 Fix for gdb/192: removed extraneous space when displaying frame level.
2377 Fix for gdb/672: update changelist is now output in mi list format.
2378 Fix for gdb/702: a -var-assign that updates the value now shows up
2379 in a subsequent -var-update.
2381 * New native configurations.
2383 FreeBSD/amd64 x86_64-*-freebsd*
2385 * Multi-arched targets.
2387 HP/PA HPUX11 hppa*-*-hpux*
2388 Renesas M32R/D w/simulator m32r-*-elf*
2390 * OBSOLETE configurations and files
2392 Configurations that have been declared obsolete in this release have
2393 been commented out. Unless there is activity to revive these
2394 configurations, the next release of GDB will have their sources
2395 permanently REMOVED.
2397 Z8000 simulator z8k-zilog-none or z8ksim
2398 Matsushita MN10200 w/simulator mn10200-*-*
2399 H8/500 simulator h8500-hitachi-hms or h8500hms
2400 HP/PA running BSD hppa*-*-bsd*
2401 HP/PA running OSF/1 hppa*-*-osf*
2402 HP/PA Pro target hppa*-*-pro*
2403 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2404 Sequent family i[3456]86-sequent-sysv4*
2405 i[3456]86-sequent-sysv*
2406 i[3456]86-sequent-bsd*
2407 Tsqware Sparclet sparclet-*-*
2408 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2410 * REMOVED configurations and files
2413 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2414 IBM AIX PS/2 i[3456]86-*-aix
2415 i386 running Mach 3.0 i[3456]86-*-mach3*
2416 i386 running Mach i[3456]86-*-mach*
2417 i386 running OSF/1 i[3456]86-*osf1mk*
2418 HP/Apollo 68k Family m68*-apollo*-sysv*,
2420 m68*-hp-bsd*, m68*-hp-hpux*
2421 Argonaut Risc Chip (ARC) arc-*-*
2422 Mitsubishi D30V d30v-*-*
2423 Fujitsu FR30 fr30-*-elf*
2424 OS/9000 i[34]86-*-os9k
2425 I960 with MON960 i960-*-coff
2427 * MIPS $fp behavior changed
2429 The convenience variable $fp, for the MIPS, now consistently returns
2430 the address of the current frame's base. Previously, depending on the
2431 context, $fp could refer to either $sp or the current frame's base
2432 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2433 The GNU Source-Level Debugger''.
2435 *** Changes in GDB 5.3:
2437 * GNU/Linux shared library multi-threaded performance improved.
2439 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2440 `/proc', in preference to `ptrace' for memory reads. This may result
2441 in an improvement in the start-up time of multi-threaded, shared
2442 library applications when run under GDB. One GDB user writes: ``loads
2443 shared libs like mad''.
2445 * ``gdbserver'' now supports multi-threaded applications on some targets
2447 Support for debugging multi-threaded applications which use
2448 the GNU/Linux LinuxThreads package has been added for
2449 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2450 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2452 * GDB now supports C/C++ preprocessor macros.
2454 GDB now expands preprocessor macro invocations in C/C++ expressions,
2455 and provides various commands for showing macro definitions and how
2458 The new command `macro expand EXPRESSION' expands any macro
2459 invocations in expression, and shows the result.
2461 The new command `show macro MACRO-NAME' shows the definition of the
2462 macro named MACRO-NAME, and where it was defined.
2464 Most compilers don't include information about macros in the debugging
2465 information by default. In GCC 3.1, for example, you need to compile
2466 your program with the options `-gdwarf-2 -g3'. If the macro
2467 information is present in the executable, GDB will read it.
2469 * Multi-arched targets.
2471 DEC Alpha (partial) alpha*-*-*
2472 DEC VAX (partial) vax-*-*
2474 National Semiconductor NS32000 (partial) ns32k-*-*
2475 Motorola 68000 (partial) m68k-*-*
2476 Motorola MCORE mcore-*-*
2480 Fujitsu FRV architecture added by Red Hat frv*-*-*
2483 * New native configurations
2485 Alpha NetBSD alpha*-*-netbsd*
2486 SH NetBSD sh*-*-netbsdelf*
2487 MIPS NetBSD mips*-*-netbsd*
2488 UltraSPARC NetBSD sparc64-*-netbsd*
2490 * OBSOLETE configurations and files
2492 Configurations that have been declared obsolete in this release have
2493 been commented out. Unless there is activity to revive these
2494 configurations, the next release of GDB will have their sources
2495 permanently REMOVED.
2497 Mitsubishi D30V d30v-*-*
2498 OS/9000 i[34]86-*-os9k
2499 IBM AIX PS/2 i[3456]86-*-aix
2500 Fujitsu FR30 fr30-*-elf*
2501 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2502 Argonaut Risc Chip (ARC) arc-*-*
2503 i386 running Mach 3.0 i[3456]86-*-mach3*
2504 i386 running Mach i[3456]86-*-mach*
2505 i386 running OSF/1 i[3456]86-*osf1mk*
2506 HP/Apollo 68k Family m68*-apollo*-sysv*,
2508 m68*-hp-bsd*, m68*-hp-hpux*
2509 I960 with MON960 i960-*-coff
2511 * OBSOLETE languages
2513 CHILL, a Pascal like language used by telecommunications companies.
2515 * REMOVED configurations and files
2517 AMD 29k family via UDI a29k-amd-udi, udi29k
2518 A29K VxWorks a29k-*-vxworks
2519 AMD 29000 embedded, using EBMON a29k-none-none
2520 AMD 29000 embedded with COFF a29k-none-coff
2521 AMD 29000 embedded with a.out a29k-none-aout
2523 testsuite/gdb.hp/gdb.threads-hp/ directory
2525 * New command "set max-user-call-depth <nnn>"
2527 This command allows the user to limit the call depth of user-defined
2528 commands. The default is 1024.
2530 * Changes in FreeBSD/i386 native debugging.
2532 Support for the "generate-core-file" has been added.
2534 * New commands "dump", "append", and "restore".
2536 These commands allow data to be copied from target memory
2537 to a bfd-format or binary file (dump and append), and back
2538 from a file into memory (restore).
2540 * Improved "next/step" support on multi-processor Alpha Tru64.
2542 The previous single-step mechanism could cause unpredictable problems,
2543 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2544 of a software single-step mechanism prevents this.
2546 *** Changes in GDB 5.2.1:
2554 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2555 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2556 Fix, by Joel Brobecker imported from mainline.
2558 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2559 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2560 Fix, by Fred Fish, imported from mainline.
2562 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2563 Surprisingly enough, it works now.
2564 By Michal Ludvig, imported from mainline.
2566 i386 hardware watchpoint support:
2567 avoid misses on second run for some targets.
2568 By Pierre Muller, imported from mainline.
2570 *** Changes in GDB 5.2:
2572 * New command "set trust-readonly-sections on[off]".
2574 This command is a hint that tells gdb that read-only sections
2575 really are read-only (ie. that their contents will not change).
2576 In this mode, gdb will go to the object file rather than the
2577 target to read memory from read-only sections (such as ".text").
2578 This can be a significant performance improvement on some
2579 (notably embedded) targets.
2581 * New command "generate-core-file" (or "gcore").
2583 This new gdb command allows the user to drop a core file of the child
2584 process state at any time. So far it's been implemented only for
2585 GNU/Linux and Solaris, but should be relatively easily ported to other
2586 hosts. Argument is core file name (defaults to core.<pid>).
2588 * New command line option
2590 GDB now accepts --pid or -p followed by a process id.
2592 * Change in command line behavior -- corefiles vs. process ids.
2594 There is a subtle behavior in the way in which GDB handles
2595 command line arguments. The first non-flag argument is always
2596 a program to debug, but the second non-flag argument may either
2597 be a corefile or a process id. Previously, GDB would attempt to
2598 open the second argument as a corefile, and if that failed, would
2599 issue a superfluous error message and then attempt to attach it as
2600 a process. Now, if the second argument begins with a non-digit,
2601 it will be treated as a corefile. If it begins with a digit,
2602 GDB will attempt to attach it as a process, and if no such process
2603 is found, will then attempt to open it as a corefile.
2605 * Changes in ARM configurations.
2607 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2608 configuration is fully multi-arch.
2610 * New native configurations
2612 ARM NetBSD arm*-*-netbsd*
2613 x86 OpenBSD i[3456]86-*-openbsd*
2614 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2615 Sparc64 running FreeBSD sparc64-*-freebsd*
2619 Sanyo XStormy16 xstormy16-elf
2621 * OBSOLETE configurations and files
2623 Configurations that have been declared obsolete in this release have
2624 been commented out. Unless there is activity to revive these
2625 configurations, the next release of GDB will have their sources
2626 permanently REMOVED.
2628 AMD 29k family via UDI a29k-amd-udi, udi29k
2629 A29K VxWorks a29k-*-vxworks
2630 AMD 29000 embedded, using EBMON a29k-none-none
2631 AMD 29000 embedded with COFF a29k-none-coff
2632 AMD 29000 embedded with a.out a29k-none-aout
2634 testsuite/gdb.hp/gdb.threads-hp/ directory
2636 * REMOVED configurations and files
2638 TI TMS320C80 tic80-*-*
2640 PowerPC Solaris powerpcle-*-solaris*
2641 PowerPC Windows NT powerpcle-*-cygwin32
2642 PowerPC Netware powerpc-*-netware*
2643 Harris/CXUX m88k m88*-harris-cxux*
2644 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2645 ns32k-utek-sysv* ns32k-utek-*
2646 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2647 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2648 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2649 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2650 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2652 * Changes to command line processing
2654 The new `--args' feature can be used to specify command-line arguments
2655 for the inferior from gdb's command line.
2657 * Changes to key bindings
2659 There is a new `operate-and-get-next' function bound to `C-o'.
2661 *** Changes in GDB 5.1.1
2663 Fix compile problem on DJGPP.
2665 Fix a problem with floating-point registers on the i386 being
2668 Fix to stop GDB crashing on .debug_str debug info.
2670 Numerous documentation fixes.
2672 Numerous testsuite fixes.
2674 *** Changes in GDB 5.1:
2676 * New native configurations
2678 Alpha FreeBSD alpha*-*-freebsd*
2679 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2680 MIPS GNU/Linux mips*-*-linux*
2681 MIPS SGI Irix 6.x mips*-sgi-irix6*
2682 ia64 AIX ia64-*-aix*
2683 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2687 Motorola 68HC11 and 68HC12 m68hc11-elf
2689 UltraSparc running GNU/Linux sparc64-*-linux*
2691 * OBSOLETE configurations and files
2693 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2694 Harris/CXUX m88k m88*-harris-cxux*
2695 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2696 ns32k-utek-sysv* ns32k-utek-*
2697 TI TMS320C80 tic80-*-*
2699 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2700 PowerPC Solaris powerpcle-*-solaris*
2701 PowerPC Windows NT powerpcle-*-cygwin32
2702 PowerPC Netware powerpc-*-netware*
2703 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2704 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2705 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2706 Apple Macintosh (MPW) host N/A
2708 stuff.c (Program to stuff files into a specially prepared space in kdb)
2709 kdb-start.c (Main loop for the standalone kernel debugger)
2711 Configurations that have been declared obsolete in this release have
2712 been commented out. Unless there is activity to revive these
2713 configurations, the next release of GDB will have their sources
2714 permanently REMOVED.
2716 * REMOVED configurations and files
2718 Altos 3068 m68*-altos-*
2719 Convex c1-*-*, c2-*-*
2721 ARM RISCix arm-*-* (as host)
2725 * GDB has been converted to ISO C.
2727 GDB's source code has been converted to ISO C. In particular, the
2728 sources are fully protoized, and rely on standard headers being
2733 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2735 * The MI enabled by default.
2737 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2738 revised and enabled by default. Packages which use GDB as a debugging
2739 engine behind a UI or another front end are encouraged to switch to
2740 using the GDB/MI interface, instead of the old annotations interface
2741 which is now deprecated.
2743 * Support for debugging Pascal programs.
2745 GDB now includes support for debugging Pascal programs. The following
2746 main features are supported:
2748 - Pascal-specific data types such as sets;
2750 - automatic recognition of Pascal sources based on file-name
2753 - Pascal-style display of data types, variables, and functions;
2755 - a Pascal expression parser.
2757 However, some important features are not yet supported.
2759 - Pascal string operations are not supported at all;
2761 - there are some problems with boolean types;
2763 - Pascal type hexadecimal constants are not supported
2764 because they conflict with the internal variables format;
2766 - support for Pascal objects and classes is not full yet;
2768 - unlike Pascal, GDB is case-sensitive for symbol names.
2770 * Changes in completion.
2772 Commands such as `shell', `run' and `set args', which pass arguments
2773 to inferior programs, now complete on file names, similar to what
2774 users expect at the shell prompt.
2776 Commands which accept locations, such as `disassemble', `print',
2777 `breakpoint', `until', etc. now complete on filenames as well as
2778 program symbols. Thus, if you type "break foob TAB", and the source
2779 files linked into the programs include `foobar.c', that file name will
2780 be one of the candidates for completion. However, file names are not
2781 considered for completion after you typed a colon that delimits a file
2782 name from a name of a function in that file, as in "break foo.c:bar".
2784 `set demangle-style' completes on available demangling styles.
2786 * New platform-independent commands:
2788 It is now possible to define a post-hook for a command as well as a
2789 hook that runs before the command. For more details, see the
2790 documentation of `hookpost' in the GDB manual.
2792 * Changes in GNU/Linux native debugging.
2794 Support for debugging multi-threaded programs has been completely
2795 revised for all platforms except m68k and sparc. You can now debug as
2796 many threads as your system allows you to have.
2798 Attach/detach is supported for multi-threaded programs.
2800 Support for SSE registers was added for x86. This doesn't work for
2801 multi-threaded programs though.
2803 * Changes in MIPS configurations.
2805 Multi-arch support is enabled for all MIPS configurations.
2807 GDB can now be built as native debugger on SGI Irix 6.x systems for
2808 debugging n32 executables. (Debugging 64-bit executables is not yet
2811 * Unified support for hardware watchpoints in all x86 configurations.
2813 Most (if not all) native x86 configurations support hardware-assisted
2814 breakpoints and watchpoints in a unified manner. This support
2815 implements debug register sharing between watchpoints, which allows to
2816 put a virtually infinite number of watchpoints on the same address,
2817 and also supports watching regions up to 16 bytes with several debug
2820 The new maintenance command `maintenance show-debug-regs' toggles
2821 debugging print-outs in functions that insert, remove, and test
2822 watchpoints and hardware breakpoints.
2824 * Changes in the DJGPP native configuration.
2826 New command ``info dos sysinfo'' displays assorted information about
2827 the CPU, OS, memory, and DPMI server.
2829 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2830 display information about segment descriptors stored in GDT, LDT, and
2833 New commands ``info dos pde'' and ``info dos pte'' display entries
2834 from Page Directory and Page Tables (for now works with CWSDPMI only).
2835 New command ``info dos address-pte'' displays the Page Table entry for
2836 a given linear address.
2838 GDB can now pass command lines longer than 126 characters to the
2839 program being debugged (requires an update to the libdbg.a library
2840 which is part of the DJGPP development kit).
2842 DWARF2 debug info is now supported.
2844 It is now possible to `step' and `next' through calls to `longjmp'.
2846 * Changes in documentation.
2848 All GDB documentation was converted to GFDL, the GNU Free
2849 Documentation License.
2851 Tracepoints-related commands are now fully documented in the GDB
2854 TUI, the Text-mode User Interface, is now documented in the manual.
2856 Tracepoints-related commands are now fully documented in the GDB
2859 The "GDB Internals" manual now has an index. It also includes
2860 documentation of `ui_out' functions, GDB coding standards, x86
2861 hardware watchpoints, and memory region attributes.
2863 * GDB's version number moved to ``version.in''
2865 The Makefile variable VERSION has been replaced by the file
2866 ``version.in''. People creating GDB distributions should update the
2867 contents of this file.
2871 GUD support is now a standard part of the EMACS distribution.
2873 *** Changes in GDB 5.0:
2875 * Improved support for debugging FP programs on x86 targets
2877 Unified and much-improved support for debugging floating-point
2878 programs on all x86 targets. In particular, ``info float'' now
2879 displays the FP registers in the same format on all x86 targets, with
2880 greater level of detail.
2882 * Improvements and bugfixes in hardware-assisted watchpoints
2884 It is now possible to watch array elements, struct members, and
2885 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2886 on x86 targets no longer erroneously trigger when the address is
2889 * Improvements in the native DJGPP version of GDB
2891 The distribution now includes all the scripts and auxiliary files
2892 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2893 machines ``out of the box''.
2895 The DJGPP version can now debug programs that use signals. It is
2896 possible to catch signals that happened in the debuggee, deliver
2897 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2898 would kill the program being debugged.) Programs that hook hardware
2899 interrupts (keyboard, timer, etc.) can also be debugged.
2901 It is now possible to debug DJGPP programs that redirect their
2902 standard handles or switch them to raw (as opposed to cooked) mode, or
2903 even close them. The command ``run < foo > bar'' works as expected,
2904 and ``info terminal'' reports useful information about the debuggee's
2905 terminal, including raw/cooked mode, redirection, etc.
2907 The DJGPP version now uses termios functions for console I/O, which
2908 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2911 DOS-style file names with drive letters are now fully supported by
2914 It is now possible to debug DJGPP programs that switch their working
2915 directory. It is also possible to rerun the debuggee any number of
2916 times without restarting GDB; thus, you can use the same setup,
2917 breakpoints, etc. for many debugging sessions.
2919 * New native configurations
2921 ARM GNU/Linux arm*-*-linux*
2922 PowerPC GNU/Linux powerpc-*-linux*
2926 Motorola MCore mcore-*-*
2927 x86 VxWorks i[3456]86-*-vxworks*
2928 PowerPC VxWorks powerpc-*-vxworks*
2929 TI TMS320C80 tic80-*-*
2931 * OBSOLETE configurations
2933 Altos 3068 m68*-altos-*
2934 Convex c1-*-*, c2-*-*
2936 ARM RISCix arm-*-* (as host)
2939 Configurations that have been declared obsolete will be commented out,
2940 but the code will be left in place. If there is no activity to revive
2941 these configurations before the next release of GDB, the sources will
2942 be permanently REMOVED.
2944 * Gould support removed
2946 Support for the Gould PowerNode and NP1 has been removed.
2948 * New features for SVR4
2950 On SVR4 native platforms (such as Solaris), if you attach to a process
2951 without first loading a symbol file, GDB will now attempt to locate and
2952 load symbols from the running process's executable file.
2954 * Many C++ enhancements
2956 C++ support has been greatly improved. Overload resolution now works properly
2957 in almost all cases. RTTI support is on the way.
2959 * Remote targets can connect to a sub-program
2961 A popen(3) style serial-device has been added. This device starts a
2962 sub-process (such as a stand-alone simulator) and then communicates
2963 with that. The sub-program to run is specified using the syntax
2964 ``|<program> <args>'' vis:
2966 (gdb) set remotedebug 1
2967 (gdb) target extended-remote |mn10300-elf-sim program-args
2969 * MIPS 64 remote protocol
2971 A long standing bug in the mips64 remote protocol where by GDB
2972 expected certain 32 bit registers (ex SR) to be transfered as 32
2973 instead of 64 bits has been fixed.
2975 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2976 added to provide backward compatibility with older versions of GDB.
2978 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2980 The command ``set remotebinarydownload'' command has been replaced by
2981 ``set remote X-packet''. Other commands in ``set remote'' family
2982 include ``set remote P-packet''.
2984 * Breakpoint commands accept ranges.
2986 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2987 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2988 ``tracepoint passcount'' also accepts a range of tracepoints.
2990 * ``apropos'' command added.
2992 The ``apropos'' command searches through command names and
2993 documentation strings, printing out matches, making it much easier to
2994 try to find a command that does what you are looking for.
2998 A new machine oriented interface (MI) has been added to GDB. This
2999 interface is designed for debug environments running GDB as a separate
3000 process. This is part of the long term libGDB project. See the
3001 "GDB/MI" chapter of the GDB manual for further information. It can be
3002 enabled by configuring with:
3004 .../configure --enable-gdbmi
3006 *** Changes in GDB-4.18:
3008 * New native configurations
3010 HP-UX 10.20 hppa*-*-hpux10.20
3011 HP-UX 11.x hppa*-*-hpux11.0*
3012 M68K GNU/Linux m68*-*-linux*
3016 Fujitsu FR30 fr30-*-elf*
3017 Intel StrongARM strongarm-*-*
3018 Mitsubishi D30V d30v-*-*
3020 * OBSOLETE configurations
3022 Gould PowerNode, NP1 np1-*-*, pn-*-*
3024 Configurations that have been declared obsolete will be commented out,
3025 but the code will be left in place. If there is no activity to revive
3026 these configurations before the next release of GDB, the sources will
3027 be permanently REMOVED.
3031 As a compatibility experiment, GDB's source files buildsym.h and
3032 buildsym.c have been converted to pure standard C, no longer
3033 containing any K&R compatibility code. We believe that all systems in
3034 use today either come with a standard C compiler, or have a GCC port
3035 available. If this is not true, please report the affected
3036 configuration to bug-gdb@gnu.org immediately. See the README file for
3037 information about getting a standard C compiler if you don't have one
3042 GDB now uses readline 2.2.
3044 * set extension-language
3046 You can now control the mapping between filename extensions and source
3047 languages by using the `set extension-language' command. For instance,
3048 you can ask GDB to treat .c files as C++ by saying
3049 set extension-language .c c++
3050 The command `info extensions' lists all of the recognized extensions
3051 and their associated languages.
3053 * Setting processor type for PowerPC and RS/6000
3055 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3056 you can use the `set processor' command to specify what variant of the
3057 PowerPC family you are debugging. The command
3061 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3062 following PowerPC and RS6000 variants:
3064 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3065 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3067 403GC IBM PowerPC 403GC
3068 505 Motorola PowerPC 505
3069 860 Motorola PowerPC 860 or 850
3070 601 Motorola PowerPC 601
3071 602 Motorola PowerPC 602
3072 603 Motorola/IBM PowerPC 603 or 603e
3073 604 Motorola PowerPC 604 or 604e
3074 750 Motorola/IBM PowerPC 750 or 750
3076 At the moment, this command just tells GDB what to name the
3077 special-purpose processor registers. Since almost all the affected
3078 registers are inaccessible to user-level programs, this command is
3079 only useful for remote debugging in its present form.
3083 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3084 more extensive support for HP-UX. Added features include shared
3085 library support, kernel threads and hardware watchpoints for 11.00,
3086 support for HP's ANSI C and C++ compilers, and a compatibility mode
3087 for xdb and dbx commands.
3091 HP's donation includes the new concept of catchpoints, which is a
3092 generalization of the old catch command. On HP-UX, it is now possible
3093 to catch exec, fork, and vfork, as well as library loading.
3095 This means that the existing catch command has changed; its first
3096 argument now specifies the type of catch to be set up. See the
3097 output of "help catch" for a list of catchpoint types.
3099 * Debugging across forks
3101 On HP-UX, you can choose which process to debug when a fork() happens
3106 HP has donated a curses-based terminal user interface (TUI). To get
3107 it, build with --enable-tui. Although this can be enabled for any
3108 configuration, at present it only works for native HP debugging.
3110 * GDB remote protocol additions
3112 A new protocol packet 'X' that writes binary data is now available.
3113 Default behavior is to try 'X', then drop back to 'M' if the stub
3114 fails to respond. The settable variable `remotebinarydownload'
3115 allows explicit control over the use of 'X'.
3117 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3118 full 64-bit address. The command
3120 set remoteaddresssize 32
3122 can be used to revert to the old behaviour. For existing remote stubs
3123 the change should not be noticed, as the additional address information
3126 In order to assist in debugging stubs, you may use the maintenance
3127 command `packet' to send any text string to the stub. For instance,
3129 maint packet heythere
3131 sends the packet "$heythere#<checksum>". Note that it is very easy to
3132 disrupt a debugging session by sending the wrong packet at the wrong
3135 The compare-sections command allows you to compare section data on the
3136 target to what is in the executable file without uploading or
3137 downloading, by comparing CRC checksums.
3139 * Tracing can collect general expressions
3141 You may now collect general expressions at tracepoints. This requires
3142 further additions to the target-side stub; see tracepoint.c and
3143 doc/agentexpr.texi for further details.
3145 * mask-address variable for Mips
3147 For Mips targets, you may control the zeroing of the upper 32 bits of
3148 a 64-bit address by entering `set mask-address on'. This is mainly
3149 of interest to users of embedded R4xxx and R5xxx processors.
3151 * Higher serial baud rates
3153 GDB's serial code now allows you to specify baud rates 57600, 115200,
3154 230400, and 460800 baud. (Note that your host system may not be able
3155 to achieve all of these rates.)
3159 The i960 configuration now includes an initial implementation of a
3160 builtin simulator, contributed by Jim Wilson.
3163 *** Changes in GDB-4.17:
3165 * New native configurations
3167 Alpha GNU/Linux alpha*-*-linux*
3168 Unixware 2.x i[3456]86-unixware2*
3169 Irix 6.x mips*-sgi-irix6*
3170 PowerPC GNU/Linux powerpc-*-linux*
3171 PowerPC Solaris powerpcle-*-solaris*
3172 Sparc GNU/Linux sparc-*-linux*
3173 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3177 Argonaut Risc Chip (ARC) arc-*-*
3178 Hitachi H8/300S h8300*-*-*
3179 Matsushita MN10200 w/simulator mn10200-*-*
3180 Matsushita MN10300 w/simulator mn10300-*-*
3181 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3182 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3183 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3184 Mitsubishi D10V w/simulator d10v-*-*
3185 Mitsubishi M32R/D w/simulator m32r-*-elf*
3186 Tsqware Sparclet sparclet-*-*
3187 NEC V850 w/simulator v850-*-*
3189 * New debugging protocols
3191 ARM with RDI protocol arm*-*-*
3192 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3193 DDB and LSI variants of PMON protocol mips*-*-*
3194 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3195 PowerPC with SDS protocol powerpc{,le}-*-eabi
3196 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3200 All configurations can now understand and use the DWARF 2 debugging
3201 format. The choice is automatic, if the symbol file contains DWARF 2
3206 GDB now includes basic Java language support. This support is
3207 only useful with Java compilers that produce native machine code.
3209 * solib-absolute-prefix and solib-search-path
3211 For SunOS and SVR4 shared libraries, you may now set the prefix for
3212 loading absolute shared library symbol files, and the search path for
3213 locating non-absolute shared library symbol files.
3215 * Live range splitting
3217 GDB can now effectively debug code for which GCC has performed live
3218 range splitting as part of its optimization. See gdb/doc/LRS for
3219 more details on the expected format of the stabs information.
3223 GDB's support for the GNU Hurd, including thread debugging, has been
3224 updated to work with current versions of the Hurd.
3228 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3229 instruction set. ARM GDB automatically detects when Thumb
3230 instructions are in use, and adjusts disassembly and backtracing
3235 GDB's MIPS target configurations now handle the MIP16 16-bit
3240 GDB now includes support for overlays; if an executable has been
3241 linked such that multiple sections are based at the same address, GDB
3242 will decide which section to use for symbolic info. You can choose to
3243 control the decision manually, using overlay commands, or implement
3244 additional target-side support and use "overlay load-target" to bring
3245 in the overlay mapping. Do "help overlay" for more detail.
3249 The command "info symbol <address>" displays information about
3250 the symbol at the specified address.
3254 The standard remote protocol now includes an extension that allows
3255 asynchronous collection and display of trace data. This requires
3256 extensive support in the target-side debugging stub. Tracing mode
3257 includes a new interaction mode in GDB and new commands: see the
3258 file tracepoint.c for more details.
3262 Configurations for embedded MIPS now include a simulator contributed
3263 by Cygnus Solutions. The simulator supports the instruction sets
3264 of most MIPS variants.
3268 Sparc configurations may now include the ERC32 simulator contributed
3269 by the European Space Agency. The simulator is not built into
3270 Sparc targets by default; configure with --enable-sim to include it.
3274 For target configurations that may include multiple variants of a
3275 basic architecture (such as MIPS and SH), you may now set the
3276 architecture explicitly. "set arch" sets, "info arch" lists
3277 the possible architectures.
3279 *** Changes in GDB-4.16:
3281 * New native configurations
3283 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3284 M68K NetBSD m68k-*-netbsd*
3285 PowerPC AIX 4.x powerpc-*-aix*
3286 PowerPC MacOS powerpc-*-macos*
3287 PowerPC Windows NT powerpcle-*-cygwin32
3288 RS/6000 AIX 4.x rs6000-*-aix4*
3292 ARM with RDP protocol arm-*-*
3293 I960 with MON960 i960-*-coff
3294 MIPS VxWorks mips*-*-vxworks*
3295 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3296 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3298 Matra Sparclet sparclet-*-*
3302 The powerpc-eabi configuration now includes the PSIM simulator,
3303 contributed by Andrew Cagney, with assistance from Mike Meissner.
3304 PSIM is a very elaborate model of the PowerPC, including not only
3305 basic instruction set execution, but also details of execution unit
3306 performance and I/O hardware. See sim/ppc/README for more details.
3310 GDB now works with Solaris 2.5.
3312 * Windows 95/NT native
3314 GDB will now work as a native debugger on Windows 95 and Windows NT.
3315 To build it from source, you must use the "gnu-win32" environment,
3316 which uses a DLL to emulate enough of Unix to run the GNU tools.
3317 Further information, binaries, and sources are available at
3318 ftp.cygnus.com, under pub/gnu-win32.
3320 * dont-repeat command
3322 If a user-defined command includes the command `dont-repeat', then the
3323 command will not be repeated if the user just types return. This is
3324 useful if the command is time-consuming to run, so that accidental
3325 extra keystrokes don't run the same command many times.
3327 * Send break instead of ^C
3329 The standard remote protocol now includes an option to send a break
3330 rather than a ^C to the target in order to interrupt it. By default,
3331 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3333 * Remote protocol timeout
3335 The standard remote protocol includes a new variable `remotetimeout'
3336 that allows you to set the number of seconds before GDB gives up trying
3337 to read from the target. The default value is 2.
3339 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3341 By default GDB will automatically keep track of objects as they are
3342 loaded and unloaded by the dynamic linker. By using the command `set
3343 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3344 when shared library events occur, thus allowing you to set breakpoints
3345 in shared libraries which are explicitly loaded by the inferior.
3347 Note this feature does not work on hpux8. On hpux9 you must link
3348 /usr/lib/end.o into your program. This feature should work
3349 automatically on hpux10.
3351 * Irix 5.x hardware watchpoint support
3353 Irix 5 configurations now support the use of hardware watchpoints.
3355 * Mips protocol "SYN garbage limit"
3357 When debugging a Mips target using the `target mips' protocol, you
3358 may set the number of characters that GDB will ignore by setting
3359 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3360 every character. The default value is 1050.
3362 * Recording and replaying remote debug sessions
3364 If you set `remotelogfile' to the name of a file, gdb will write to it
3365 a recording of a remote debug session. This recording may then be
3366 replayed back to gdb using "gdbreplay". See gdbserver/README for
3367 details. This is useful when you have a problem with GDB while doing
3368 remote debugging; you can make a recording of the session and send it
3369 to someone else, who can then recreate the problem.
3371 * Speedups for remote debugging
3373 GDB includes speedups for downloading and stepping MIPS systems using
3374 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3375 and more efficient S-record downloading.
3377 * Memory use reductions and statistics collection
3379 GDB now uses less memory and reports statistics about memory usage.
3380 Try the `maint print statistics' command, for example.
3382 *** Changes in GDB-4.15:
3384 * Psymtabs for XCOFF
3386 The symbol reader for AIX GDB now uses partial symbol tables. This
3387 can greatly improve startup time, especially for large executables.
3389 * Remote targets use caching
3391 Remote targets now use a data cache to speed up communication with the
3392 remote side. The data cache could lead to incorrect results because
3393 it doesn't know about volatile variables, thus making it impossible to
3394 debug targets which use memory mapped I/O devices. `set remotecache
3395 off' turns the the data cache off.
3397 * Remote targets may have threads
3399 The standard remote protocol now includes support for multiple threads
3400 in the target system, using new protocol commands 'H' and 'T'. See
3401 gdb/remote.c for details.
3405 If GDB is configured with `--enable-netrom', then it will include
3406 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3407 acts as though it is a bank of ROM on the target board, but you can
3408 write into it over the network. GDB's support consists only of
3409 support for fast loading into the emulated ROM; to debug, you must use
3410 another protocol, such as standard remote protocol. The usual
3411 sequence is something like
3413 target nrom <netrom-hostname>
3415 target remote <netrom-hostname>:1235
3419 GDB now includes support for the Apple Macintosh, as a host only. It
3420 may be run as either an MPW tool or as a standalone application, and
3421 it can debug through the serial port. All the usual GDB commands are
3422 available, but to the target command, you must supply "serial" as the
3423 device type instead of "/dev/ttyXX". See mpw-README in the main
3424 directory for more information on how to build. The MPW configuration
3425 scripts */mpw-config.in support only a few targets, and only the
3426 mips-idt-ecoff target has been tested.
3430 GDB configuration now uses autoconf. This is not user-visible,
3431 but does simplify configuration and building.
3435 GDB now supports hpux10.
3437 *** Changes in GDB-4.14:
3439 * New native configurations
3441 x86 FreeBSD i[345]86-*-freebsd
3442 x86 NetBSD i[345]86-*-netbsd
3443 NS32k NetBSD ns32k-*-netbsd
3444 Sparc NetBSD sparc-*-netbsd
3448 A29K VxWorks a29k-*-vxworks
3449 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3450 CPU32 EST-300 emulator m68*-*-est*
3451 PowerPC ELF powerpc-*-elf
3454 * Alpha OSF/1 support for procfs
3456 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3457 possible to attach to running processes. As the mounting of the /proc
3458 filesystem is optional on the Alpha, GDB automatically determines
3459 the availability of /proc during startup. This can lead to problems
3460 if /proc is unmounted after GDB has been started.
3462 * Arguments to user-defined commands
3464 User commands may accept up to 10 arguments separated by whitespace.
3465 Arguments are accessed within the user command via $arg0..$arg9. A
3468 print $arg0 + $arg1 + $arg2
3470 To execute the command use:
3473 Defines the command "adder" which prints the sum of its three arguments.
3474 Note the arguments are text substitutions, so they may reference variables,
3475 use complex expressions, or even perform inferior function calls.
3477 * New `if' and `while' commands
3479 This makes it possible to write more sophisticated user-defined
3480 commands. Both commands take a single argument, which is the
3481 expression to evaluate, and must be followed by the commands to
3482 execute, one per line, if the expression is nonzero, the list being
3483 terminated by the word `end'. The `if' command list may include an
3484 `else' word, which causes the following commands to be executed only
3485 if the expression is zero.
3487 * Fortran source language mode
3489 GDB now includes partial support for Fortran 77. It will recognize
3490 Fortran programs and can evaluate a subset of Fortran expressions, but
3491 variables and functions may not be handled correctly. GDB will work
3492 with G77, but does not yet know much about symbols emitted by other
3495 * Better HPUX support
3497 Most debugging facilities now work on dynamic executables for HPPAs
3498 running hpux9 or later. You can attach to running dynamically linked
3499 processes, but by default the dynamic libraries will be read-only, so
3500 for instance you won't be able to put breakpoints in them. To change
3501 that behavior do the following before running the program:
3507 This will cause the libraries to be mapped private and read-write.
3508 To revert to the normal behavior, do this:
3514 You cannot set breakpoints or examine data in the library until after
3515 the library is loaded if the function/data symbols do not have
3518 GDB can now also read debug symbols produced by the HP C compiler on
3519 HPPAs (sorry, no C++, Fortran or 68k support).
3521 * Target byte order now dynamically selectable
3523 You can choose which byte order to use with a target system, via the
3524 commands "set endian big" and "set endian little", and you can see the
3525 current setting by using "show endian". You can also give the command
3526 "set endian auto", in which case GDB will use the byte order
3527 associated with the executable. Currently, only embedded MIPS
3528 configurations support dynamic selection of target byte order.
3530 * New DOS host serial code
3532 This version uses DPMI interrupts to handle buffered I/O, so you
3533 no longer need to run asynctsr when debugging boards connected to
3536 *** Changes in GDB-4.13:
3538 * New "complete" command
3540 This lists all the possible completions for the rest of the line, if it
3541 were to be given as a command itself. This is intended for use by emacs.
3543 * Trailing space optional in prompt
3545 "set prompt" no longer adds a space for you after the prompt you set. This
3546 allows you to set a prompt which ends in a space or one that does not.
3548 * Breakpoint hit counts
3550 "info break" now displays a count of the number of times the breakpoint
3551 has been hit. This is especially useful in conjunction with "ignore"; you
3552 can ignore a large number of breakpoint hits, look at the breakpoint info
3553 to see how many times the breakpoint was hit, then run again, ignoring one
3554 less than that number, and this will get you quickly to the last hit of
3557 * Ability to stop printing at NULL character
3559 "set print null-stop" will cause GDB to stop printing the characters of
3560 an array when the first NULL is encountered. This is useful when large
3561 arrays actually contain only short strings.
3563 * Shared library breakpoints
3565 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3566 breakpoints in shared libraries before the executable is run.
3568 * Hardware watchpoints
3570 There is a new hardware breakpoint for the watch command for sparclite
3571 targets. See gdb/sparclite/hw_breakpoint.note.
3573 Hardware watchpoints are also now supported under GNU/Linux.
3577 Annotations have been added. These are for use with graphical interfaces,
3578 and are still experimental. Currently only gdba.el uses these.
3580 * Improved Irix 5 support
3582 GDB now works properly with Irix 5.2.
3584 * Improved HPPA support
3586 GDB now works properly with the latest GCC and GAS.
3588 * New native configurations
3590 Sequent PTX4 i[34]86-sequent-ptx4
3591 HPPA running OSF/1 hppa*-*-osf*
3592 Atari TT running SVR4 m68*-*-sysv4*
3593 RS/6000 LynxOS rs6000-*-lynxos*
3597 OS/9000 i[34]86-*-os9k
3598 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3601 * Hitachi SH7000 and E7000-PC ICE support
3603 There is now support for communicating with the Hitachi E7000-PC ICE.
3604 This is available automatically when GDB is configured for the SH.
3608 As usual, a variety of small fixes and improvements, both generic
3609 and configuration-specific. See the ChangeLog for more detail.
3611 *** Changes in GDB-4.12:
3613 * Irix 5 is now supported
3617 GDB-4.12 on the HPPA has a number of changes which make it unable
3618 to debug the output from the currently released versions of GCC and
3619 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3620 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3621 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3624 *** Changes in GDB-4.11:
3626 * User visible changes:
3630 The "set remotedebug" option is now consistent between the mips remote
3631 target, remote targets using the gdb-specific protocol, UDI (AMD's
3632 debug protocol for the 29k) and the 88k bug monitor. It is now an
3633 integer specifying a debug level (normally 0 or 1, but 2 means more
3634 debugging info for the mips target).
3636 * DEC Alpha native support
3638 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3639 debug info, but GDB works fairly well with the DEC compiler and should
3640 work with a future GCC release. See the README file for a few
3641 Alpha-specific notes.
3643 * Preliminary thread implementation
3645 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3647 * LynxOS native and target support for 386
3649 This release has been hosted on LynxOS 2.2, and also can be configured
3650 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3653 * Improvements in C++ mangling/demangling.
3655 This release has much better g++ debugging, specifically in name
3656 mangling/demangling, virtual function calls, print virtual table,
3657 call methods, ...etc.
3659 *** Changes in GDB-4.10:
3661 * User visible changes:
3663 Remote debugging using the GDB-specific (`target remote') protocol now
3664 supports the `load' command. This is only useful if you have some
3665 other way of getting the stub to the target system, and you can put it
3666 somewhere in memory where it won't get clobbered by the download.
3668 Filename completion now works.
3670 When run under emacs mode, the "info line" command now causes the
3671 arrow to point to the line specified. Also, "info line" prints
3672 addresses in symbolic form (as well as hex).
3674 All vxworks based targets now support a user settable option, called
3675 vxworks-timeout. This option represents the number of seconds gdb
3676 should wait for responses to rpc's. You might want to use this if
3677 your vxworks target is, perhaps, a slow software simulator or happens
3678 to be on the far side of a thin network line.
3682 This release contains support for using a DEC alpha as a GDB host for
3683 cross debugging. Native alpha debugging is not supported yet.
3686 *** Changes in GDB-4.9:
3690 This is the first GDB release which is accompanied by a matching testsuite.
3691 The testsuite requires installation of dejagnu, which should be available
3692 via ftp from most sites that carry GNU software.
3696 'Cfront' style demangling has had its name changed to 'ARM' style, to
3697 emphasize that it was written from the specifications in the C++ Annotated
3698 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3699 disclaimers, it still generated too much confusion with users attempting to
3700 use gdb with AT&T cfront.
3704 GDB now uses a standard remote interface to a simulator library.
3705 So far, the library contains simulators for the Zilog Z8001/2, the
3706 Hitachi H8/300, H8/500 and Super-H.
3708 * New targets supported
3710 H8/300 simulator h8300-hitachi-hms or h8300hms
3711 H8/500 simulator h8500-hitachi-hms or h8500hms
3712 SH simulator sh-hitachi-hms or sh
3713 Z8000 simulator z8k-zilog-none or z8ksim
3714 IDT MIPS board over serial line mips-idt-ecoff
3716 Cross-debugging to GO32 targets is supported. It requires a custom
3717 version of the i386-stub.c module which is integrated with the
3718 GO32 memory extender.
3720 * New remote protocols
3722 MIPS remote debugging protocol.
3724 * New source languages supported
3726 This version includes preliminary support for Chill, a Pascal like language
3727 used by telecommunications companies. Chill support is also being integrated
3728 into the GNU compiler, but we don't know when it will be publically available.
3731 *** Changes in GDB-4.8:
3733 * HP Precision Architecture supported
3735 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3736 version of this support was available as a set of patches from the
3737 University of Utah. GDB does not support debugging of programs
3738 compiled with the HP compiler, because HP will not document their file
3739 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3740 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3742 Many problems in the preliminary version have been fixed.
3744 * Faster and better demangling
3746 We have improved template demangling and fixed numerous bugs in the GNU style
3747 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3748 character types (wchar_t) are now supported. Demangling of each symbol is now
3749 only done once, and is cached when the symbol table for a file is read in.
3750 This results in a small increase in memory usage for C programs, a moderate
3751 increase in memory usage for C++ programs, and a fantastic speedup in
3754 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3755 from the specifications in the Annotated Reference Manual, which AT&T's
3756 compiler does not actually implement.
3758 * G++ multiple inheritance compiler problem
3760 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3761 inheritance lattices was reworked to properly discover ambiguities. We
3762 recently found an example which causes this new algorithm to fail in a
3763 very subtle way, producing bad debug information for those classes.
3764 The file 'gcc.patch' (in this directory) can be applied to gcc to
3765 circumvent the problem. A future GCC release will contain a complete
3768 The previous G++ debug info problem (mentioned below for the gdb-4.7
3769 release) is fixed in gcc version 2.3.2.
3771 * Improved configure script
3773 The `configure' script will now attempt to guess your system type if
3774 you don't supply a host system type. The old scheme of supplying a
3775 host system triplet is preferable over using this. All the magic is
3776 done in the new `config.guess' script. Examine it for details.
3778 We have also brought our configure script much more in line with the FSF's
3779 version. It now supports the --with-xxx options. In particular,
3780 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3781 The resulting GDB will not be able to read arbitrary object file formats --
3782 only the format ``expected'' to be used on the configured target system.
3783 We hope to make this the default in a future release.
3785 * Documentation improvements
3787 There's new internal documentation on how to modify GDB, and how to
3788 produce clean changes to the code. We implore people to read it
3789 before submitting changes.
3791 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3792 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3793 `info' files are also provided. To build `info' files from scratch,
3794 you will need the latest `makeinfo' release, which will be available in
3795 a future texinfo-X.Y release.
3797 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3798 We're not sure exactly which versions have this problem, but it has
3799 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3800 or better. If that isn't possible, there is a patch in
3801 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3802 around this problem.
3806 GDB now supports array constants that can be used in expressions typed in by
3807 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3808 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3811 The new directory `gdb/sparclite' contains a program that demonstrates
3812 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3814 * New native hosts supported
3816 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3817 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3819 * New targets supported
3821 AMD 29k family via UDI a29k-amd-udi or udi29k
3823 * New file formats supported
3825 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3826 HPUX core files, and SCO 3.2v2 core files.
3830 Attaching to processes now works again; thanks for the many bug reports.
3832 We have also stomped on a bunch of core dumps caused by
3833 printf_filtered("%s") problems.
3835 We eliminated a copyright problem on the rpc and ptrace header files
3836 for VxWorks, which was discovered at the last minute during the 4.7
3837 release. You should now be able to build a VxWorks GDB.
3839 You can now interrupt gdb while an attached process is running. This
3840 will cause the attached process to stop, and give control back to GDB.
3842 We fixed problems caused by using too many file descriptors
3843 for reading symbols from object files and libraries. This was
3844 especially a problem for programs that used many (~100) shared
3847 The `step' command now only enters a subroutine if there is line number
3848 information for the subroutine. Otherwise it acts like the `next'
3849 command. Previously, `step' would enter subroutines if there was
3850 any debugging information about the routine. This avoids problems
3851 when using `cc -g1' on MIPS machines.
3853 * Internal improvements
3855 GDB's internal interfaces have been improved to make it easier to support
3856 debugging of multiple languages in the future.
3858 GDB now uses a common structure for symbol information internally.
3859 Minimal symbols (derived from linkage symbols in object files), partial
3860 symbols (from a quick scan of debug information), and full symbols
3861 contain a common subset of information, making it easier to write
3862 shared code that handles any of them.
3864 * New command line options
3866 We now accept --silent as an alias for --quiet.
3870 The memory-mapped-malloc library is now licensed under the GNU Library
3871 General Public License.
3873 *** Changes in GDB-4.7:
3875 * Host/native/target split
3877 GDB has had some major internal surgery to untangle the support for
3878 hosts and remote targets. Now, when you configure GDB for a remote
3879 target, it will no longer load in all of the support for debugging
3880 local programs on the host. When fully completed and tested, this will
3881 ensure that arbitrary host/target combinations are possible.
3883 The primary conceptual shift is to separate the non-portable code in
3884 GDB into three categories. Host specific code is required any time GDB
3885 is compiled on that host, regardless of the target. Target specific
3886 code relates to the peculiarities of the target, but can be compiled on
3887 any host. Native specific code is everything else: it can only be
3888 built when the host and target are the same system. Child process
3889 handling and core file support are two common `native' examples.
3891 GDB's use of /proc for controlling Unix child processes is now cleaner.
3892 It has been split out into a single module under the `target_ops' vector,
3893 plus two native-dependent functions for each system that uses /proc.
3895 * New hosts supported
3897 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3898 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3899 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3901 * New targets supported
3903 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3904 68030 and CPU32 m68030-*-*, m68332-*-*
3906 * New native hosts supported
3908 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3909 (386bsd is not well tested yet)
3910 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3912 * New file formats supported
3914 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3915 supports reading of `a.out.adobe' object files, which are an a.out
3916 format extended with minimal information about multiple sections.
3920 `show copying' is the same as the old `info copying'.
3921 `show warranty' is the same as `info warrantee'.
3922 These were renamed for consistency. The old commands continue to work.
3924 `info handle' is a new alias for `info signals'.
3926 You can now define pre-command hooks, which attach arbitrary command
3927 scripts to any command. The commands in the hook will be executed
3928 prior to the user's command. You can also create a hook which will be
3929 executed whenever the program stops. See gdb.texinfo.
3933 We now deal with Cfront style name mangling, and can even extract type
3934 info from mangled symbols. GDB can automatically figure out which
3935 symbol mangling style your C++ compiler uses.
3937 Calling of methods and virtual functions has been improved as well.
3941 The crash that occured when debugging Sun Ansi-C compiled binaries is
3942 fixed. This was due to mishandling of the extra N_SO stabs output
3945 We also finally got Ultrix 4.2 running in house, and fixed core file
3946 support, with help from a dozen people on the net.
3948 John M. Farrell discovered that the reason that single-stepping was so
3949 slow on all of the Mips based platforms (primarily SGI and DEC) was
3950 that we were trying to demangle and lookup a symbol used for internal
3951 purposes on every instruction that was being stepped through. Changing
3952 the name of that symbol so that it couldn't be mistaken for a C++
3953 mangled symbol sped things up a great deal.
3955 Rich Pixley sped up symbol lookups in general by getting much smarter
3956 about when C++ symbol mangling is necessary. This should make symbol
3957 completion (TAB on the command line) much faster. It's not as fast as
3958 we'd like, but it's significantly faster than gdb-4.6.
3962 A new user controllable variable 'call_scratch_address' can
3963 specify the location of a scratch area to be used when GDB
3964 calls a function in the target. This is necessary because the
3965 usual method of putting the scratch area on the stack does not work
3966 in systems that have separate instruction and data spaces.
3968 We integrated changes to support the 29k UDI (Universal Debugger
3969 Interface), but discovered at the last minute that we didn't have all
3970 of the appropriate copyright paperwork. We are working with AMD to
3971 resolve this, and hope to have it available soon.
3975 We have sped up the remote serial line protocol, especially for targets
3976 with lots of registers. It now supports a new `expedited status' ('T')
3977 message which can be used in place of the existing 'S' status message.
3978 This allows the remote stub to send only the registers that GDB
3979 needs to make a quick decision about single-stepping or conditional
3980 breakpoints, eliminating the need to fetch the entire register set for
3981 each instruction being stepped through.
3983 The GDB remote serial protocol now implements a write-through cache for
3984 registers, only re-reading the registers if the target has run.
3986 There is also a new remote serial stub for SPARC processors. You can
3987 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3988 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3989 processor with a serial port.
3993 Configure.in files have become much easier to read and modify. A new
3994 `table driven' format makes it more obvious what configurations are
3995 supported, and what files each one uses.
3999 There is a new opcodes library which will eventually contain all of the
4000 disassembly routines and opcode tables. At present, it only contains
4001 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4002 disassembler (binutils/objdump) to share these routines.
4004 The libiberty library is now copylefted under the GNU Library General
4005 Public License. This allows more liberal use, and was done so libg++
4006 can use it. This makes no difference to GDB, since the Library License
4007 grants all the rights from the General Public License.
4011 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4012 reference to the stabs symbol info used by the debugger. It is (as far
4013 as we know) the only published document on this fascinating topic. We
4014 encourage you to read it, compare it to the stabs information on your
4015 system, and send improvements on the document in general (to
4016 bug-gdb@prep.ai.mit.edu).
4018 And, of course, many bugs have been fixed.
4021 *** Changes in GDB-4.6:
4023 * Better support for C++ function names
4025 GDB now accepts as input the "demangled form" of C++ overloaded function
4026 names and member function names, and can do command completion on such names
4027 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4028 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4029 Make use of command completion, it is your friend.
4031 GDB also now accepts a variety of C++ mangled symbol formats. They are
4032 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4033 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4034 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4035 for the list of formats.
4037 * G++ symbol mangling problem
4039 Recent versions of gcc have a bug in how they emit debugging information for
4040 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4041 directory) can be applied to gcc to fix the problem. Alternatively, if you
4042 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4043 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4044 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4047 * New 'maintenance' command
4049 All of the commands related to hacking GDB internals have been moved out of
4050 the main command set, and now live behind the 'maintenance' command. This
4051 can also be abbreviated as 'mt'. The following changes were made:
4053 dump-me -> maintenance dump-me
4054 info all-breakpoints -> maintenance info breakpoints
4055 printmsyms -> maintenance print msyms
4056 printobjfiles -> maintenance print objfiles
4057 printpsyms -> maintenance print psymbols
4058 printsyms -> maintenance print symbols
4060 The following commands are new:
4062 maintenance demangle Call internal GDB demangler routine to
4063 demangle a C++ link name and prints the result.
4064 maintenance print type Print a type chain for a given symbol
4066 * Change to .gdbinit file processing
4068 We now read the $HOME/.gdbinit file before processing the argv arguments
4069 (e.g. reading symbol files or core files). This allows global parameters to
4070 be set, which will apply during the symbol reading. The ./.gdbinit is still
4071 read after argv processing.
4073 * New hosts supported
4075 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4077 GNU/Linux support i386-unknown-linux or linux
4079 We are also including code to support the HP/PA running BSD and HPUX. This
4080 is almost guaranteed not to work, as we didn't have time to test or build it
4081 for this release. We are including it so that the more adventurous (or
4082 masochistic) of you can play with it. We also had major problems with the
4083 fact that the compiler that we got from HP doesn't support the -g option.
4086 * New targets supported
4088 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4090 * More smarts about finding #include files
4092 GDB now remembers the compilation directory for all include files, and for
4093 all files from which C is generated (like yacc and lex sources). This
4094 greatly improves GDB's ability to find yacc/lex sources, and include files,
4095 especially if you are debugging your program from a directory different from
4096 the one that contains your sources.
4098 We also fixed a bug which caused difficulty with listing and setting
4099 breakpoints in include files which contain C code. (In the past, you had to
4100 try twice in order to list an include file that you hadn't looked at before.)
4102 * Interesting infernals change
4104 GDB now deals with arbitrary numbers of sections, where the symbols for each
4105 section must be relocated relative to that section's landing place in the
4106 target's address space. This work was needed to support ELF with embedded
4107 stabs used by Solaris-2.0.
4109 * Bug fixes (of course!)
4111 There have been loads of fixes for the following things:
4112 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4113 i960, stabs, DOS(GO32), procfs, etc...
4115 See the ChangeLog for details.
4117 *** Changes in GDB-4.5:
4119 * New machines supported (host and target)
4121 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4123 SGI Irix-4.x mips-sgi-irix4 or iris4
4125 * New malloc package
4127 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4128 Mmalloc is capable of handling mutiple heaps of memory. It is also
4129 capable of saving a heap to a file, and then mapping it back in later.
4130 This can be used to greatly speedup the startup of GDB by using a
4131 pre-parsed symbol table which lives in a mmalloc managed heap. For
4132 more details, please read mmalloc/mmalloc.texi.
4136 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4137 'help info proc' for details.
4139 * MIPS ecoff symbol table format
4141 The code that reads MIPS symbol table format is now supported on all hosts.
4142 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4145 * File name changes for MS-DOS
4147 Many files in the config directories have been renamed to make it easier to
4148 support GDB on MS-DOSe systems (which have very restrictive file name
4149 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4150 environment) is close to working but has some remaining problems. Note
4151 that debugging of DOS programs is not supported, due to limitations
4152 in the ``operating system'', but it can be used to host cross-debugging.
4154 * Cross byte order fixes
4156 Many fixes have been made to support cross debugging of Sparc and MIPS
4157 targets from hosts whose byte order differs.
4159 * New -mapped and -readnow options
4161 If memory-mapped files are available on your system through the 'mmap'
4162 system call, you can use the -mapped option on the `file' or
4163 `symbol-file' commands to cause GDB to write the symbols from your
4164 program into a reusable file. If the program you are debugging is
4165 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4166 Future GDB debugging sessions will notice the presence of this file,
4167 and will quickly map in symbol information from it, rather than reading
4168 the symbol table from the executable program. Using the '-mapped'
4169 option in a GDB `file' or `symbol-file' command has the same effect as
4170 starting GDB with the '-mapped' command-line option.
4172 You can cause GDB to read the entire symbol table immediately by using
4173 the '-readnow' option with any of the commands that load symbol table
4174 information (or on the GDB command line). This makes the command
4175 slower, but makes future operations faster.
4177 The -mapped and -readnow options are typically combined in order to
4178 build a `fred.syms' file that contains complete symbol information.
4179 A simple GDB invocation to do nothing but build a `.syms' file for future
4182 gdb -batch -nx -mapped -readnow programname
4184 The `.syms' file is specific to the host machine on which GDB is run.
4185 It holds an exact image of GDB's internal symbol table. It cannot be
4186 shared across multiple host platforms.
4188 * longjmp() handling
4190 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4191 siglongjmp() without losing control. This feature has not yet been ported to
4192 all systems. It currently works on many 386 platforms, all MIPS-based
4193 platforms (SGI, DECstation, etc), and Sun3/4.
4197 Preliminary work has been put in to support the new Solaris OS from Sun. At
4198 this time, it can control and debug processes, but it is not capable of
4203 As always, many many bug fixes. The major areas were with g++, and mipsread.
4204 People using the MIPS-based platforms should experience fewer mysterious
4205 crashes and trashed symbol tables.
4207 *** Changes in GDB-4.4:
4209 * New machines supported (host and target)
4211 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4213 BSD Reno on Vax vax-dec-bsd
4214 Ultrix on Vax vax-dec-ultrix
4216 * New machines supported (target)
4218 AMD 29000 embedded, using EBMON a29k-none-none
4222 GDB continues to improve its handling of C++. `References' work better.
4223 The demangler has also been improved, and now deals with symbols mangled as
4224 per the Annotated C++ Reference Guide.
4226 GDB also now handles `stabs' symbol information embedded in MIPS
4227 `ecoff' symbol tables. Since the ecoff format was not easily
4228 extensible to handle new languages such as C++, this appeared to be a
4229 good way to put C++ debugging info into MIPS binaries. This option
4230 will be supported in the GNU C compiler, version 2, when it is
4233 * New features for SVR4
4235 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4236 shared libraries. Debugging dynamically linked programs should present
4237 only minor differences from debugging statically linked programs.
4239 The `info proc' command will print out information about any process
4240 on an SVR4 system (including the one you are debugging). At the moment,
4241 it prints the address mappings of the process.
4243 If you bring up GDB on another SVR4 system, please send mail to
4244 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4246 * Better dynamic linking support in SunOS
4248 Reading symbols from shared libraries which contain debugging symbols
4249 now works properly. However, there remain issues such as automatic
4250 skipping of `transfer vector' code during function calls, which
4251 make it harder to debug code in a shared library, than to debug the
4252 same code linked statically.
4256 GDB is now using the latest `getopt' routines from the FSF. This
4257 version accepts the -- prefix for options with long names. GDB will
4258 continue to accept the old forms (-option and +option) as well.
4259 Various single letter abbreviations for options have been explicity
4260 added to the option table so that they won't get overshadowed in the
4261 future by other options that begin with the same letter.
4265 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4266 Many assorted bugs have been handled. Many more remain to be handled.
4267 See the various ChangeLog files (primarily in gdb and bfd) for details.
4270 *** Changes in GDB-4.3:
4272 * New machines supported (host and target)
4274 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4275 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4276 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4278 * Almost SCO Unix support
4280 We had hoped to support:
4281 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4282 (except for core file support), but we discovered very late in the release
4283 that it has problems with process groups that render gdb unusable. Sorry
4284 about that. I encourage people to fix it and post the fixes.
4286 * Preliminary ELF and DWARF support
4288 GDB can read ELF object files on System V Release 4, and can handle
4289 debugging records for C, in DWARF format, in ELF files. This support
4290 is preliminary. If you bring up GDB on another SVR4 system, please
4291 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4296 GDB now uses the latest `readline' library. One user-visible change
4297 is that two tabs will list possible command completions, which previously
4298 required typing M-? (meta-question mark, or ESC ?).
4302 The `stepi' bug that many of you noticed has been squashed.
4303 Many bugs in C++ have been handled. Many more remain to be handled.
4304 See the various ChangeLog files (primarily in gdb and bfd) for details.
4306 * State of the MIPS world (in case you wondered):
4308 GDB can understand the symbol tables emitted by the compilers
4309 supplied by most vendors of MIPS-based machines, including DEC. These
4310 symbol tables are in a format that essentially nobody else uses.
4312 Some versions of gcc come with an assembler post-processor called
4313 mips-tfile. This program is required if you want to do source-level
4314 debugging of gcc-compiled programs. I believe FSF does not ship
4315 mips-tfile with gcc version 1, but it will eventually come with gcc
4318 Debugging of g++ output remains a problem. g++ version 1.xx does not
4319 really support it at all. (If you're lucky, you should be able to get
4320 line numbers and stack traces to work, but no parameters or local
4321 variables.) With some work it should be possible to improve the
4324 When gcc version 2 is released, you will have somewhat better luck.
4325 However, even then you will get confusing results for inheritance and
4328 We will eventually provide full debugging of g++ output on
4329 DECstations. This will probably involve some kind of stabs-in-ecoff
4330 encapulation, but the details have not been worked out yet.
4333 *** Changes in GDB-4.2:
4335 * Improved configuration
4337 Only one copy of `configure' exists now, and it is not self-modifying.
4338 Porting BFD is simpler.
4342 The `step' and `next' commands now only stop at the first instruction
4343 of a source line. This prevents the multiple stops that used to occur
4344 in switch statements, for-loops, etc. `Step' continues to stop if a
4345 function that has debugging information is called within the line.
4349 Lots of small bugs fixed. More remain.
4351 * New host supported (not target)
4353 Intel 386 PC clone running Mach i386-none-mach
4356 *** Changes in GDB-4.1:
4358 * Multiple source language support
4360 GDB now has internal scaffolding to handle several source languages.
4361 It determines the type of each source file from its filename extension,
4362 and will switch expression parsing and number formatting to match the
4363 language of the function in the currently selected stack frame.
4364 You can also specifically set the language to be used, with
4365 `set language c' or `set language modula-2'.
4369 GDB now has preliminary support for the GNU Modula-2 compiler,
4370 currently under development at the State University of New York at
4371 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4372 continue through the fall of 1991 and into 1992.
4374 Other Modula-2 compilers are currently not supported, and attempting to
4375 debug programs compiled with them will likely result in an error as the
4376 symbol table is read. Feel free to work on it, though!
4378 There are hooks in GDB for strict type checking and range checking,
4379 in the `Modula-2 philosophy', but they do not currently work.
4383 GDB can now write to executable and core files (e.g. patch
4384 a variable's value). You must turn this switch on, specify
4385 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4386 by assigning a new value to a variable. Modifications take
4389 * Automatic SunOS shared library reading
4391 When you run your program, GDB automatically determines where its
4392 shared libraries (if any) have been loaded, and reads their symbols.
4393 The `share' command is no longer needed. This also works when
4394 examining core files.
4398 You can specify the number of lines that the `list' command shows.
4401 * New machines supported (host and target)
4403 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4404 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4405 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4407 * New hosts supported (not targets)
4409 IBM RT/PC: romp-ibm-aix or rtpc
4411 * New targets supported (not hosts)
4413 AMD 29000 embedded with COFF a29k-none-coff
4414 AMD 29000 embedded with a.out a29k-none-aout
4415 Ultracomputer remote kernel debug a29k-nyu-kern
4417 * New remote interfaces
4423 *** Changes in GDB-4.0:
4427 Wide output is wrapped at good places to make the output more readable.
4429 Gdb now supports cross-debugging from a host machine of one type to a
4430 target machine of another type. Communication with the target system
4431 is over serial lines. The ``target'' command handles connecting to the
4432 remote system; the ``load'' command will download a program into the
4433 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4434 also supports debugging of realtime processes running under VxWorks,
4435 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4436 stub on the target system.
4438 New CPUs supported include the AMD 29000 and Intel 960.
4440 GDB now reads object files and symbol tables via a ``binary file''
4441 library, which allows a single copy of GDB to debug programs of multiple
4442 object file types such as a.out and coff.
4444 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4445 refcard.dvi and refcard.ps are available to format it).
4448 * Control-Variable user interface simplified
4450 All variables that control the operation of the debugger can be set
4451 by the ``set'' command, and displayed by the ``show'' command.
4453 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4454 ``Show prompt'' produces the response:
4455 Gdb's prompt is new-gdb=>.
4457 What follows are the NEW set commands. The command ``help set'' will
4458 print a complete list of old and new set commands. ``help set FOO''
4459 will give a longer description of the variable FOO. ``show'' will show
4460 all of the variable descriptions and their current settings.
4462 confirm on/off: Enables warning questions for operations that are
4463 hard to recover from, e.g. rerunning the program while
4464 it is already running. Default is ON.
4466 editing on/off: Enables EMACS style command line editing
4467 of input. Previous lines can be recalled with
4468 control-P, the current line can be edited with control-B,
4469 you can search for commands with control-R, etc.
4472 history filename NAME: NAME is where the gdb command history
4473 will be stored. The default is .gdb_history,
4474 or the value of the environment variable
4477 history size N: The size, in commands, of the command history. The
4478 default is 256, or the value of the environment variable
4481 history save on/off: If this value is set to ON, the history file will
4482 be saved after exiting gdb. If set to OFF, the
4483 file will not be saved. The default is OFF.
4485 history expansion on/off: If this value is set to ON, then csh-like
4486 history expansion will be performed on
4487 command line input. The default is OFF.
4489 radix N: Sets the default radix for input and output. It can be set
4490 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4491 in the current radix, so "set radix 10" is always a no-op.
4493 height N: This integer value is the number of lines on a page. Default
4494 is 24, the current `stty rows'' setting, or the ``li#''
4495 setting from the termcap entry matching the environment
4498 width N: This integer value is the number of characters on a line.
4499 Default is 80, the current `stty cols'' setting, or the ``co#''
4500 setting from the termcap entry matching the environment
4503 Note: ``set screensize'' is obsolete. Use ``set height'' and
4504 ``set width'' instead.
4506 print address on/off: Print memory addresses in various command displays,
4507 such as stack traces and structure values. Gdb looks
4508 more ``symbolic'' if you turn this off; it looks more
4509 ``machine level'' with it on. Default is ON.
4511 print array on/off: Prettyprint arrays. New convenient format! Default
4514 print demangle on/off: Print C++ symbols in "source" form if on,
4517 print asm-demangle on/off: Same, for assembler level printouts
4520 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4523 * Support for Epoch Environment.
4525 The epoch environment is a version of Emacs v18 with windowing. One
4526 new command, ``inspect'', is identical to ``print'', except that if you
4527 are running in the epoch environment, the value is printed in its own
4531 * Support for Shared Libraries
4533 GDB can now debug programs and core files that use SunOS shared libraries.
4534 Symbols from a shared library cannot be referenced
4535 before the shared library has been linked with the program (this
4536 happens after you type ``run'' and before the function main() is entered).
4537 At any time after this linking (including when examining core files
4538 from dynamically linked programs), gdb reads the symbols from each
4539 shared library when you type the ``sharedlibrary'' command.
4540 It can be abbreviated ``share''.
4542 sharedlibrary REGEXP: Load shared object library symbols for files
4543 matching a unix regular expression. No argument
4544 indicates to load symbols for all shared libraries.
4546 info sharedlibrary: Status of loaded shared libraries.
4551 A watchpoint stops execution of a program whenever the value of an
4552 expression changes. Checking for this slows down execution
4553 tremendously whenever you are in the scope of the expression, but is
4554 quite useful for catching tough ``bit-spreader'' or pointer misuse
4555 problems. Some machines such as the 386 have hardware for doing this
4556 more quickly, and future versions of gdb will use this hardware.
4558 watch EXP: Set a watchpoint (breakpoint) for an expression.
4560 info watchpoints: Information about your watchpoints.
4562 delete N: Deletes watchpoint number N (same as breakpoints).
4563 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4564 enable N: Re-enables watchpoint number N (same as breakpoints).
4567 * C++ multiple inheritance
4569 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4572 * C++ exception handling
4574 Gdb now supports limited C++ exception handling. Besides the existing
4575 ability to breakpoint on an exception handler, gdb can breakpoint on
4576 the raising of an exception (before the stack is peeled back to the
4579 catch FOO: If there is a FOO exception handler in the dynamic scope,
4580 set a breakpoint to catch exceptions which may be raised there.
4581 Multiple exceptions (``catch foo bar baz'') may be caught.
4583 info catch: Lists all exceptions which may be caught in the
4584 current stack frame.
4587 * Minor command changes
4589 The command ``call func (arg, arg, ...)'' now acts like the print
4590 command, except it does not print or save a value if the function's result
4591 is void. This is similar to dbx usage.
4593 The ``up'' and ``down'' commands now always print the frame they end up
4594 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4595 frames without printing.
4597 * New directory command
4599 'dir' now adds directories to the FRONT of the source search path.
4600 The path starts off empty. Source files that contain debug information
4601 about the directory in which they were compiled can be found even
4602 with an empty path; Sun CC and GCC include this information. If GDB can't
4603 find your source file in the current directory, type "dir .".
4605 * Configuring GDB for compilation
4607 For normal use, type ``./configure host''. See README or gdb.texinfo
4610 GDB now handles cross debugging. If you are remotely debugging between
4611 two different machines, type ``./configure host -target=targ''.
4612 Host is the machine where GDB will run; targ is the machine
4613 where the program that you are debugging will run.