1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.3.1
6 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
7 and "show remote hardware-watchpoint-length-limit". These allows to
8 set or show the maximum length limit (in bytes) of a remote
9 target hardware watchpoint.
11 This allows e.g. to use "unlimited" hardware watchpoints with the
12 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
13 watchpoints are slower than real hardware watchpoints but are
14 significantly faster than gdb software watchpoints.
18 ** The "maint set python print-stack on|off" command has been
19 deprecated, and a new command: "set python print-stack on|off" has
20 replaced it. Additionally, the default for "print-stack" is now
23 ** A prompt subsitution hook (prompt_hook) is now available to the
26 ** A new command set/show extended-prompt has been added.
28 ** A new Python module, gdb.prompt has been added to the GDB Python
29 modules library. This module provides functionality for
30 escape sequentions in prompts (used by set/show
31 extended-prompt). These escape sequences are replaced by their
34 ** Python commands and convenience-functions located in
35 'data-directory'/python/gdb/command and
36 'data-directory'/python/gdb/function are now automatically loaded
39 ** Symbols now provide the "type" attribute, the type of the symbol.
41 ** The "gdb.breakpoint" function has been deprecated in favor of
44 ** Type objects for struct and union types now allow access to
45 the fields using standard Python dictionary (mapping) methods.
46 For example, "some_type['myfield']" now works, as does
49 ** A new event "gdb.new_objfile" has been added, triggered by loading a
52 * libthread-db-search-path now supports two special values: $sdir and $pdir.
53 $sdir specifies the default system locations of shared libraries.
54 $pdir specifies the directory where the libpthread used by the application
57 GDB no longer looks in $sdir and $pdir after it has searched the directories
58 mentioned in libthread-db-search-path. If you want to search those
59 directories, they must be specified in libthread-db-search-path.
60 The default value of libthread-db-search-path on GNU/Linux and Solaris
61 systems is now "$sdir:$pdir".
63 $pdir is not supported by gdbserver, it is currently ignored.
64 $sdir is supported by gdbserver.
66 * New configure option --with-iconv-bin.
67 When using the internationalization support like the one in the GNU C
68 library, GDB will invoke the "iconv" program to get a list of supported
69 character sets. If this program lives in a non-standard location, one can
70 use this option to specify where to find it.
72 * When natively debugging programs on PowerPC BookE processors running
73 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
74 watchpoints, which specify a mask in addition to an address to watch.
75 The mask specifies that some bits of an address (the bits which are
76 reset in the mask) should be ignored when matching the address accessed
77 by the inferior against the watchpoint address. See the "PowerPC Embedded"
78 section in the user manual for more details.
80 * The new option --once causes GDBserver to stop listening for connections once
81 the first connection is made. The listening port used by GDBserver will
82 become available after that.
84 * New commands "info macros", and "info definitions" have been added.
86 * New function parameters suffix @entry specifies value of function parameter
87 at the time the function got called. Entry values are available only since
92 watch EXPRESSION mask MASK_VALUE
93 The watch command now supports the mask argument which allows creation
94 of masked watchpoints, if the current architecture supports this feature.
96 info auto-load-scripts [REGEXP]
97 This command was formerly named "maintenance print section-scripts".
98 It is now generally useful and is no longer a maintenance-only command.
100 * Tracepoints can now be enabled and disabled at any time after a trace
101 experiment has been started using the standard "enable" and "disable"
102 commands. It is now possible to start a trace experiment with no enabled
103 tracepoints; GDB will display a warning, but will allow the experiment to
104 begin, assuming that tracepoints will be enabled as needed while the trace
109 set print entry-values (both|compact|default|if-needed|no|only|preferred)
110 show print entry-values
111 Set printing of frame argument values at function entry. In some cases
112 GDB can determine the value of function argument which was passed by the
113 function caller, even if the value was modified inside the called function.
115 set debug entry-values
116 show debug entry-values
117 Control display of debugging info for determining frame argument values at
118 function entry and virtual tail call frames.
124 Dynamically enable a tracepoint in a started trace experiment.
128 Dynamically disable a tracepoint in a started trace experiment.
130 * Dcache size (number of lines) and line-size are now runtime-configurable
131 via "set dcache line" and "set dcache line-size" commands.
135 Texas Instruments TMS320C6x tic6x-*-*
137 *** Changes in GDB 7.3.1
139 * The build failure for NetBSD and OpenBSD targets have now been fixed.
141 *** Changes in GDB 7.3
143 * GDB has a new command: "thread find [REGEXP]".
144 It finds the thread id whose name, target id, or thread extra info
145 matches the given regular expression.
147 * The "catch syscall" command now works on mips*-linux* targets.
149 * The -data-disassemble MI command now supports modes 2 and 3 for
150 dumping the instruction opcodes.
152 * New command line options
154 -data-directory DIR Specify DIR as the "data-directory".
155 This is mostly for testing purposes.
157 * The "maint set python auto-load on|off" command has been renamed to
158 "set auto-load-scripts on|off".
160 * GDB has a new command: "set directories".
161 It is like the "dir" command except that it replaces the
162 source path list instead of augmenting it.
164 * GDB now understands thread names.
166 On GNU/Linux, "info threads" will display the thread name as set by
167 prctl or pthread_setname_np.
169 There is also a new command, "thread name", which can be used to
170 assign a name internally for GDB to display.
173 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
174 has been integrated into GDB.
178 ** The function gdb.Write now accepts an optional keyword 'stream'.
179 This keyword, when provided, will direct the output to either
180 stdout, stderr, or GDB's logging output.
182 ** Parameters can now be be sub-classed in Python, and in particular
183 you may implement the get_set_doc and get_show_doc functions.
184 This improves how Parameter set/show documentation is processed
185 and allows for more dynamic content.
187 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
188 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
189 have an is_valid method.
191 ** Breakpoints can now be sub-classed in Python, and in particular
192 you may implement a 'stop' function that is executed each time
193 the inferior reaches that breakpoint.
195 ** New function gdb.lookup_global_symbol looks up a global symbol.
197 ** GDB values in Python are now callable if the value represents a
198 function. For example, if 'some_value' represents a function that
199 takes two integer parameters and returns a value, you can call
200 that function like so:
202 result = some_value (10,20)
204 ** Module gdb.types has been added.
205 It contains a collection of utilities for working with gdb.Types objects:
206 get_basic_type, has_field, make_enum_dict.
208 ** Module gdb.printing has been added.
209 It contains utilities for writing and registering pretty-printers.
210 New classes: PrettyPrinter, SubPrettyPrinter,
211 RegexpCollectionPrettyPrinter.
212 New function: register_pretty_printer.
214 ** New commands "info pretty-printers", "enable pretty-printer" and
215 "disable pretty-printer" have been added.
217 ** gdb.parameter("directories") is now available.
219 ** New function gdb.newest_frame returns the newest frame in the
222 ** The gdb.InferiorThread class has a new "name" attribute. This
223 holds the thread's name.
225 ** Python Support for Inferior events.
226 Python scripts can add observers to be notified of events
227 occurring in the process being debugged.
228 The following events are currently supported:
229 - gdb.events.cont Continue event.
230 - gdb.events.exited Inferior exited event.
231 - gdb.events.stop Signal received, and Breakpoint hit events.
235 ** GDB now puts template parameters in scope when debugging in an
236 instantiation. For example, if you have:
238 template<int X> int func (void) { return X; }
240 then if you step into func<5>, "print X" will show "5". This
241 feature requires proper debuginfo support from the compiler; it
242 was added to GCC 4.5.
244 ** The motion commands "next", "finish", "until", and "advance" now
245 work better when exceptions are thrown. In particular, GDB will
246 no longer lose control of the inferior; instead, the GDB will
247 stop the inferior at the point at which the exception is caught.
248 This functionality requires a change in the exception handling
249 code that was introduced in GCC 4.5.
251 * GDB now follows GCC's rules on accessing volatile objects when
252 reading or writing target state during expression evaluation.
253 One notable difference to prior behavior is that "print x = 0"
254 no longer generates a read of x; the value of the assignment is
255 now always taken directly from the value being assigned.
257 * GDB now has some support for using labels in the program's source in
258 linespecs. For instance, you can use "advance label" to continue
259 execution to a label.
261 * GDB now has support for reading and writing a new .gdb_index
262 section. This section holds a fast index of DWARF debugging
263 information and can be used to greatly speed up GDB startup and
264 operation. See the documentation for `save gdb-index' for details.
266 * The "watch" command now accepts an optional "-location" argument.
267 When used, this causes GDB to watch the memory referred to by the
268 expression. Such a watchpoint is never deleted due to it going out
271 * GDB now supports thread debugging of core dumps on GNU/Linux.
273 GDB now activates thread debugging using the libthread_db library
274 when debugging GNU/Linux core dumps, similarly to when debugging
275 live processes. As a result, when debugging a core dump file, GDB
276 is now able to display pthread_t ids of threads. For example, "info
277 threads" shows the same output as when debugging the process when it
278 was live. In earlier releases, you'd see something like this:
281 * 1 LWP 6780 main () at main.c:10
283 While now you see this:
286 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
288 It is also now possible to inspect TLS variables when debugging core
291 When debugging a core dump generated on a machine other than the one
292 used to run GDB, you may need to point GDB at the correct
293 libthread_db library with the "set libthread-db-search-path"
294 command. See the user manual for more details on this command.
296 * When natively debugging programs on PowerPC BookE processors running
297 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
298 which stop execution of the inferior whenever it executes an instruction
299 at any address within the specified range. See the "PowerPC Embedded"
300 section in the user manual for more details.
302 * New features in the GDB remote stub, GDBserver
304 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
305 and i686 LynxOS (version 5.x).
307 ** GDBserver is now supported on Blackfin Linux.
309 * New native configurations
311 ia64 HP-UX ia64-*-hpux*
315 Analog Devices, Inc. Blackfin Processor bfin-*
317 * Ada task switching is now supported on sparc-elf targets when
318 debugging a program using the Ravenscar Profile. For more information,
319 see the "Tasking Support when using the Ravenscar Profile" section
320 in the GDB user manual.
322 * Guile support was removed.
324 * New features in the GNU simulator
326 ** The --map-info flag lists all known core mappings.
328 ** CFI flashes may be simulated via the "cfi" device.
330 *** Changes in GDB 7.2
332 * Shared library support for remote targets by default
334 When GDB is configured for a generic, non-OS specific target, like
335 for example, --target=arm-eabi or one of the many *-*-elf targets,
336 GDB now queries remote stubs for loaded shared libraries using the
337 `qXfer:libraries:read' packet. Previously, shared library support
338 was always disabled for such configurations.
342 ** Argument Dependent Lookup (ADL)
344 In C++ ADL lookup directs function search to the namespaces of its
345 arguments even if the namespace has not been imported.
355 Here the compiler will search for `foo' in the namespace of 'b'
356 and find A::foo. GDB now supports this. This construct is commonly
357 used in the Standard Template Library for operators.
359 ** Improved User Defined Operator Support
361 In addition to member operators, GDB now supports lookup of operators
362 defined in a namespace and imported with a `using' directive, operators
363 defined in the global scope, operators imported implicitly from an
364 anonymous namespace, and the ADL operators mentioned in the previous
366 GDB now also supports proper overload resolution for all the previously
367 mentioned flavors of operators.
369 ** static const class members
371 Printing of static const class members that are initialized in the
372 class definition has been fixed.
374 * Windows Thread Information Block access.
376 On Windows targets, GDB now supports displaying the Windows Thread
377 Information Block (TIB) structure. This structure is visible either
378 by using the new command `info w32 thread-information-block' or, by
379 dereferencing the new convenience variable named `$_tlb', a
380 thread-specific pointer to the TIB. This feature is also supported
381 when remote debugging using GDBserver.
385 Static tracepoints are calls in the user program into a tracing
386 library. One such library is a port of the LTTng kernel tracer to
387 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
388 When debugging with GDBserver, GDB now supports combining the GDB
389 tracepoint machinery with such libraries. For example: the user can
390 use GDB to probe a static tracepoint marker (a call from the user
391 program into the tracing library) with the new "strace" command (see
392 "New commands" below). This creates a "static tracepoint" in the
393 breakpoint list, that can be manipulated with the same feature set
394 as fast and regular tracepoints. E.g., collect registers, local and
395 global variables, collect trace state variables, and define
396 tracepoint conditions. In addition, the user can collect extra
397 static tracepoint marker specific data, by collecting the new
398 $_sdata internal variable. When analyzing the trace buffer, you can
399 inspect $_sdata like any other variable available to GDB. For more
400 information, see the "Tracepoints" chapter in GDB user manual. New
401 remote packets have been defined to support static tracepoints, see
402 the "New remote packets" section below.
404 * Better reconstruction of tracepoints after disconnected tracing
406 GDB will attempt to download the original source form of tracepoint
407 definitions when starting a trace run, and then will upload these
408 upon reconnection to the target, resulting in a more accurate
409 reconstruction of the tracepoints that are in use on the target.
413 You can now exercise direct control over the ways that GDB can
414 affect your program. For instance, you can disallow the setting of
415 breakpoints, so that the program can run continuously (assuming
416 non-stop mode). In addition, the "observer" variable is available
417 to switch all of the different controls; in observer mode, GDB
418 cannot affect the target's behavior at all, which is useful for
419 tasks like diagnosing live systems in the field.
421 * The new convenience variable $_thread holds the number of the
428 Return the address of the Windows Thread Information Block of a given thread.
432 In response to several of the tracepoint packets, the target may now
433 also respond with a number of intermediate `qRelocInsn' request
434 packets before the final result packet, to have GDB handle
435 relocating an instruction to execute at a different address. This
436 is particularly useful for stubs that support fast tracepoints. GDB
437 reports support for this feature in the qSupported packet.
441 List static tracepoint markers in the target program.
445 List static tracepoint markers at a given address in the target
448 qXfer:statictrace:read
450 Read the static trace data collected (by a `collect $_sdata'
451 tracepoint action). The remote stub reports support for this packet
452 to gdb's qSupported query.
456 Send the current settings of GDB's permission flags.
460 Send part of the source (textual) form of a tracepoint definition,
461 which includes location, conditional, and action list.
463 * The source command now accepts a -s option to force searching for the
464 script in the source search path even if the script name specifies
467 * New features in the GDB remote stub, GDBserver
469 - GDBserver now support tracepoints (including fast tracepoints, and
470 static tracepoints). The feature is currently supported by the
471 i386-linux and amd64-linux builds. See the "Tracepoints support
472 in gdbserver" section in the manual for more information.
474 GDBserver JIT compiles the tracepoint's conditional agent
475 expression bytecode into native code whenever possible for low
476 overhead dynamic tracepoints conditionals. For such tracepoints,
477 an expression that examines program state is evaluated when the
478 tracepoint is reached, in order to determine whether to capture
479 trace data. If the condition is simple and false, processing the
480 tracepoint finishes very quickly and no data is gathered.
482 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
483 for static tracepoints support.
485 - GDBserver now supports x86_64 Windows 64-bit debugging.
487 * GDB now sends xmlRegisters= in qSupported packet to indicate that
488 it understands register description.
490 * The --batch flag now disables pagination and queries.
492 * X86 general purpose registers
494 GDB now supports reading/writing byte, word and double-word x86
495 general purpose registers directly. This means you can use, say,
496 $ah or $ax to refer, respectively, to the byte register AH and
497 16-bit word register AX that are actually portions of the 32-bit
498 register EAX or 64-bit register RAX.
500 * The `commands' command now accepts a range of breakpoints to modify.
501 A plain `commands' following a command that creates multiple
502 breakpoints affects all the breakpoints set by that command. This
503 applies to breakpoints set by `rbreak', and also applies when a
504 single `break' command creates multiple breakpoints (e.g.,
505 breakpoints on overloaded c++ functions).
507 * The `rbreak' command now accepts a filename specification as part of
508 its argument, limiting the functions selected by the regex to those
509 in the specified file.
511 * Support for remote debugging Windows and SymbianOS shared libraries
512 from Unix hosts has been improved. Non Windows GDB builds now can
513 understand target reported file names that follow MS-DOS based file
514 system semantics, such as file names that include drive letters and
515 use the backslash character as directory separator. This makes it
516 possible to transparently use the "set sysroot" and "set
517 solib-search-path" on Unix hosts to point as host copies of the
518 target's shared libraries. See the new command "set
519 target-file-system-kind" described below, and the "Commands to
520 specify files" section in the user manual for more information.
524 eval template, expressions...
525 Convert the values of one or more expressions under the control
526 of the string template to a command line, and call it.
528 set target-file-system-kind unix|dos-based|auto
529 show target-file-system-kind
530 Set or show the assumed file system kind for target reported file
533 save breakpoints <filename>
534 Save all current breakpoint definitions to a file suitable for use
535 in a later debugging session. To read the saved breakpoint
536 definitions, use the `source' command.
538 `save tracepoints' is a new alias for `save-tracepoints'. The latter
541 info static-tracepoint-markers
542 Display information about static tracepoint markers in the target.
544 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
545 Define a static tracepoint by probing a marker at the given
546 function, line, address, or marker ID.
550 Enable and disable observer mode.
552 set may-write-registers on|off
553 set may-write-memory on|off
554 set may-insert-breakpoints on|off
555 set may-insert-tracepoints on|off
556 set may-insert-fast-tracepoints on|off
557 set may-interrupt on|off
558 Set individual permissions for GDB effects on the target. Note that
559 some of these settings can have undesirable or surprising
560 consequences, particularly when changed in the middle of a session.
561 For instance, disabling the writing of memory can prevent
562 breakpoints from being inserted, cause single-stepping to fail, or
563 even crash your program, if you disable after breakpoints have been
564 inserted. However, GDB should not crash.
566 set record memory-query on|off
567 show record memory-query
568 Control whether to stop the inferior if memory changes caused
569 by an instruction cannot be recorded.
574 The disassemble command now supports "start,+length" form of two arguments.
578 ** GDB now provides a new directory location, called the python directory,
579 where Python scripts written for GDB can be installed. The location
580 of that directory is <data-directory>/python, where <data-directory>
581 is the GDB data directory. For more details, see section `Scripting
582 GDB using Python' in the manual.
584 ** The GDB Python API now has access to breakpoints, symbols, symbol
585 tables, program spaces, inferiors, threads and frame's code blocks.
586 Additionally, GDB Parameters can now be created from the API, and
587 manipulated via set/show in the CLI.
589 ** New functions gdb.target_charset, gdb.target_wide_charset,
590 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
592 ** New exception gdb.GdbError.
594 ** Pretty-printers are now also looked up in the current program space.
596 ** Pretty-printers can now be individually enabled and disabled.
598 ** GDB now looks for names of Python scripts to auto-load in a
599 special section named `.debug_gdb_scripts', in addition to looking
600 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
602 * Tracepoint actions were unified with breakpoint commands. In particular,
603 there are no longer differences in "info break" output for breakpoints and
604 tracepoints and the "commands" command can be used for both tracepoints and
609 ARM Symbian arm*-*-symbianelf*
611 * D language support.
612 GDB now supports debugging programs written in the D programming
615 * GDB now supports the extended ptrace interface for PowerPC which is
616 available since Linux kernel version 2.6.34. This automatically enables
617 any hardware breakpoints and additional hardware watchpoints available in
618 the processor. The old ptrace interface exposes just one hardware
619 watchpoint and no hardware breakpoints.
621 * GDB is now able to use the Data Value Compare (DVC) register available on
622 embedded PowerPC processors to implement in hardware simple watchpoint
623 conditions of the form:
625 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
627 This works in native GDB running on Linux kernels with the extended ptrace
628 interface mentioned above.
630 *** Changes in GDB 7.1
636 GDB now supports importing of namespaces in C++. This enables the
637 user to inspect variables from imported namespaces. Support for
638 namepace aliasing has also been added. So, if a namespace is
639 aliased in the current scope (e.g. namepace C=A; ) the user can
640 print variables using the alias (e.g. (gdb) print C::x).
644 All known bugs relating to the printing of virtual base class were
645 fixed. It is now possible to call overloaded static methods using a
650 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
651 and reinterpret_cast<> are now handled by the C++ expression parser.
655 Xilinx MicroBlaze microblaze-*-*
660 Xilinx MicroBlaze microblaze
663 * Multi-program debugging.
665 GDB now has support for multi-program (a.k.a. multi-executable or
666 multi-exec) debugging. This allows for debugging multiple inferiors
667 simultaneously each running a different program under the same GDB
668 session. See "Debugging Multiple Inferiors and Programs" in the
669 manual for more information. This implied some user visible changes
670 in the multi-inferior support. For example, "info inferiors" now
671 lists inferiors that are not running yet or that have exited
672 already. See also "New commands" and "New options" below.
674 * New tracing features
676 GDB's tracepoint facility now includes several new features:
678 ** Trace state variables
680 GDB tracepoints now include support for trace state variables, which
681 are variables managed by the target agent during a tracing
682 experiment. They are useful for tracepoints that trigger each
683 other, so for instance one tracepoint can count hits in a variable,
684 and then a second tracepoint has a condition that is true when the
685 count reaches a particular value. Trace state variables share the
686 $-syntax of GDB convenience variables, and can appear in both
687 tracepoint actions and condition expressions. Use the "tvariable"
688 command to create, and "info tvariables" to view; see "Trace State
689 Variables" in the manual for more detail.
693 GDB now includes an option for defining fast tracepoints, which
694 targets may implement more efficiently, such as by installing a jump
695 into the target agent rather than a trap instruction. The resulting
696 speedup can be by two orders of magnitude or more, although the
697 tradeoff is that some program locations on some target architectures
698 might not allow fast tracepoint installation, for instance if the
699 instruction to be replaced is shorter than the jump. To request a
700 fast tracepoint, use the "ftrace" command, with syntax identical to
701 the regular trace command.
703 ** Disconnected tracing
705 It is now possible to detach GDB from the target while it is running
706 a trace experiment, then reconnect later to see how the experiment
707 is going. In addition, a new variable disconnected-tracing lets you
708 tell the target agent whether to continue running a trace if the
709 connection is lost unexpectedly.
713 GDB now has the ability to save the trace buffer into a file, and
714 then use that file as a target, similarly to you can do with
715 corefiles. You can select trace frames, print data that was
716 collected in them, and use tstatus to display the state of the
717 tracing run at the moment that it was saved. To create a trace
718 file, use "tsave <filename>", and to use it, do "target tfile
721 ** Circular trace buffer
723 You can ask the target agent to handle the trace buffer as a
724 circular buffer, discarding the oldest trace frames to make room for
725 newer ones, by setting circular-trace-buffer to on. This feature may
726 not be available for all target agents.
731 The disassemble command, when invoked with two arguments, now requires
732 the arguments to be comma-separated.
735 The info variables command now displays variable definitions. Files
736 which only declare a variable are not shown.
739 The source command is now capable of sourcing Python scripts.
740 This feature is dependent on the debugger being build with Python
743 Related to this enhancement is also the introduction of a new command
744 "set script-extension" (see below).
746 * New commands (for set/show, see "New options" below)
748 record save [<FILENAME>]
749 Save a file (in core file format) containing the process record
750 execution log for replay debugging at a later time.
752 record restore <FILENAME>
753 Restore the process record execution log that was saved at an
754 earlier time, for replay debugging.
756 add-inferior [-copies <N>] [-exec <FILENAME>]
759 clone-inferior [-copies <N>] [ID]
760 Make a new inferior ready to execute the same program another
766 maint info program-spaces
767 List the program spaces loaded into GDB.
769 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
770 show remote interrupt-sequence
771 Allow the user to select one of ^C, a BREAK signal or BREAK-g
772 as the sequence to the remote target in order to interrupt the execution.
773 Ctrl-C is a default. Some system prefers BREAK which is high level of
774 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
775 Magic SysRq g. It is BREAK signal and character 'g'.
777 set remote interrupt-on-connect [on | off]
778 show remote interrupt-on-connect
779 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
780 remote target when gdb connects to it. This is needed when you debug
783 set remotebreak [on | off]
785 Deprecated. Use "set/show remote interrupt-sequence" instead.
787 tvariable $NAME [ = EXP ]
788 Create or modify a trace state variable.
791 List trace state variables and their values.
793 delete tvariable $NAME ...
794 Delete one or more trace state variables.
797 Evaluate the given expressions without collecting anything into the
798 trace buffer. (Valid in tracepoint actions only.)
800 ftrace FN / FILE:LINE / *ADDR
801 Define a fast tracepoint at the given function, line, or address.
803 * New expression syntax
805 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
806 GDB now parses 0b101010 identically with 42.
810 set follow-exec-mode new|same
811 show follow-exec-mode
812 Control whether GDB reuses the same inferior across an exec call or
813 creates a new one. This is useful to be able to restart the old
814 executable after the inferior having done an exec call.
816 set default-collect EXPR, ...
818 Define a list of expressions to be collected at each tracepoint.
819 This is a useful way to ensure essential items are not overlooked,
820 such as registers or a critical global variable.
822 set disconnected-tracing
823 show disconnected-tracing
824 If set to 1, the target is instructed to continue tracing if it
825 loses its connection to GDB. If 0, the target is to stop tracing
828 set circular-trace-buffer
829 show circular-trace-buffer
830 If set to on, the target is instructed to use a circular trace buffer
831 and discard the oldest trace frames instead of stopping the trace due
832 to a full trace buffer. If set to off, the trace stops when the buffer
833 fills up. Some targets may not support this.
835 set script-extension off|soft|strict
836 show script-extension
837 If set to "off", the debugger does not perform any script language
838 recognition, and all sourced files are assumed to be GDB scripts.
839 If set to "soft" (the default), files are sourced according to
840 filename extension, falling back to GDB scripts if the first
842 If set to "strict", files are sourced according to filename extension.
844 set ada trust-PAD-over-XVS on|off
845 show ada trust-PAD-over-XVS
846 If off, activate a workaround against a bug in the debugging information
847 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
848 the GCC sources for more information about the GNAT encoding and
849 PAD types in particular). It is always safe to set this option to
850 off, but this introduces a slight performance penalty. The default
853 * Python API Improvements
855 ** GDB provides the new class gdb.LazyString. This is useful in
856 some pretty-printing cases. The new method gdb.Value.lazy_string
857 provides a simple way to create objects of this type.
859 ** The fields returned by gdb.Type.fields now have an
860 `is_base_class' attribute.
862 ** The new method gdb.Type.range returns the range of an array type.
864 ** The new method gdb.parse_and_eval can be used to parse and
865 evaluate an expression.
870 Define a trace state variable.
873 Get the current value of a trace state variable.
876 Set desired tracing behavior upon disconnection.
879 Set the trace buffer to be linear or circular.
882 Get data about the tracepoints currently in use.
886 Process record now works correctly with hardware watchpoints.
888 Multiple bug fixes have been made to the mips-irix port, making it
889 much more reliable. In particular:
890 - Debugging threaded applications is now possible again. Previously,
891 GDB would hang while starting the program, or while waiting for
892 the program to stop at a breakpoint.
893 - Attaching to a running process no longer hangs.
894 - An error occurring while loading a core file has been fixed.
895 - Changing the value of the PC register now works again. This fixes
896 problems observed when using the "jump" command, or when calling
897 a function from GDB, or even when assigning a new value to $pc.
898 - With the "finish" and "return" commands, the return value for functions
899 returning a small array is now correctly printed.
900 - It is now possible to break on shared library code which gets executed
901 during a shared library init phase (code executed while executing
902 their .init section). Previously, the breakpoint would have no effect.
903 - GDB is now able to backtrace through the signal handler for
904 non-threaded programs.
906 PIE (Position Independent Executable) programs debugging is now supported.
907 This includes debugging execution of PIC (Position Independent Code) shared
908 libraries although for that, it should be possible to run such libraries as an
911 *** Changes in GDB 7.0
913 * GDB now has an interface for JIT compilation. Applications that
914 dynamically generate code can create symbol files in memory and register
915 them with GDB. For users, the feature should work transparently, and
916 for JIT developers, the interface is documented in the GDB manual in the
917 "JIT Compilation Interface" chapter.
919 * Tracepoints may now be conditional. The syntax is as for
920 breakpoints; either an "if" clause appended to the "trace" command,
921 or the "condition" command is available. GDB sends the condition to
922 the target for evaluation using the same bytecode format as is used
923 for tracepoint actions.
925 * The disassemble command now supports: an optional /r modifier, print the
926 raw instructions in hex as well as in symbolic form, and an optional /m
927 modifier to print mixed source+assembly.
929 * Process record and replay
931 In a architecture environment that supports ``process record and
932 replay'', ``process record and replay'' target can record a log of
933 the process execution, and replay it with both forward and reverse
936 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
937 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
938 set execution-direction {forward|reverse}, for targets that support
941 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
942 feature is available with a native GDB running on kernel version
945 * GDB now has support for multi-byte and wide character sets on the
946 target. Strings whose character type is wchar_t, char16_t, or
947 char32_t are now correctly printed. GDB supports wide- and unicode-
948 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
949 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
950 `printf'. This feature requires iconv to work properly; if your
951 system does not have a working iconv, GDB can use GNU libiconv. See
952 the installation instructions for more information.
954 * GDB now supports automatic retrieval of shared library files from
955 remote targets. To use this feature, specify a system root that begins
956 with the `remote:' prefix, either via the `set sysroot' command or via
957 the `--with-sysroot' configure-time option.
959 * "info sharedlibrary" now takes an optional regex of libraries to show,
960 and it now reports if a shared library has no debugging information.
962 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
963 now complete on file names.
965 * When completing in expressions, gdb will attempt to limit
966 completions to allowable structure or union fields, where appropriate.
967 For instance, consider:
969 # struct example { int f1; double f2; };
970 # struct example variable;
973 If the user types TAB at the end of this command line, the available
974 completions will be "f1" and "f2".
976 * Inlined functions are now supported. They show up in backtraces, and
977 the "step", "next", and "finish" commands handle them automatically.
979 * GDB now supports the token-splicing (##) and stringification (#)
980 operators when expanding macros. It also supports variable-arity
983 * GDB now supports inspecting extra signal information, exported by
984 the new $_siginfo convenience variable. The feature is currently
985 implemented on linux ARM, i386 and amd64.
987 * GDB can now display the VFP floating point registers and NEON vector
988 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
989 can provide these registers (requires Linux 2.6.30 or later). Remote
990 and simulator targets may also provide them.
995 Search memory for a sequence of bytes.
998 Turn off `+'/`-' protocol acknowledgments to permit more efficient
999 operation over reliable transport links. Use of this packet is
1000 controlled by the `set remote noack-packet' command.
1003 Kill the process with the specified process ID. Use this in preference
1004 to `k' when multiprocess protocol extensions are supported.
1007 Obtains additional operating system information
1011 Read or write additional signal information.
1013 * Removed remote protocol undocumented extension
1015 An undocumented extension to the remote protocol's `S' stop reply
1016 packet that permited the stub to pass a process id was removed.
1017 Remote servers should use the `T' stop reply packet instead.
1019 * GDB now supports multiple function calling conventions according to the
1020 DWARF-2 DW_AT_calling_convention function attribute.
1022 * The SH target utilizes the aforementioned change to distinguish between gcc
1023 and Renesas calling convention. It also adds the new CLI commands
1024 `set/show sh calling-convention'.
1026 * GDB can now read compressed debug sections, as produced by GNU gold
1027 with the --compress-debug-sections=zlib flag.
1029 * 64-bit core files are now supported on AIX.
1031 * Thread switching is now supported on Tru64.
1033 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1034 which will be allocated using malloc later in program execution.
1036 * The qXfer:libraries:read remote procotol packet now allows passing a
1037 list of section offsets.
1039 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1040 conditions handling signals delivered during attach or thread creation
1041 have also been fixed.
1043 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1044 From the user's standpoint, all unqualified instances of True and False
1045 are treated as the standard definitions, regardless of context.
1047 * GDB now parses C++ symbol and type names more flexibly. For
1050 template<typename T> class C { };
1053 GDB will now correctly handle all of:
1055 ptype C<char const *>
1056 ptype C<char const*>
1057 ptype C<const char *>
1058 ptype C<const char*>
1060 * New features in the GDB remote stub, gdbserver
1062 - The "--wrapper" command-line argument tells gdbserver to use a
1063 wrapper program to launch programs for debugging.
1065 - On PowerPC and S/390 targets, it is now possible to use a single
1066 gdbserver executable to debug both 32-bit and 64-bit programs.
1067 (This requires gdbserver itself to be built as a 64-bit executable.)
1069 - gdbserver uses the new noack protocol mode for TCP connections to
1070 reduce communications latency, if also supported and enabled in GDB.
1072 - Support for the sparc64-linux-gnu target is now included in
1075 - The amd64-linux build of gdbserver now supports debugging both
1076 32-bit and 64-bit programs.
1078 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1079 now support hardware watchpoints, and will use them automatically
1084 GDB now has support for scripting using Python. Whether this is
1085 available is determined at configure time.
1087 New GDB commands can now be written in Python.
1089 * Ada tasking support
1091 Ada tasks can now be inspected in GDB. The following commands have
1095 Print the list of Ada tasks.
1097 Print detailed information about task number N.
1099 Print the task number of the current task.
1101 Switch the context of debugging to task number N.
1103 * Support for user-defined prefixed commands. The "define" command can
1104 add new commands to existing prefixes, e.g. "target".
1106 * Multi-inferior, multi-process debugging.
1108 GDB now has generalized support for multi-inferior debugging. See
1109 "Debugging Multiple Inferiors" in the manual for more information.
1110 Although availability still depends on target support, the command
1111 set is more uniform now. The GNU/Linux specific multi-forks support
1112 has been migrated to this new framework. This implied some user
1113 visible changes; see "New commands" and also "Removed commands"
1116 * Target descriptions can now describe the target OS ABI. See the
1117 "Target Description Format" section in the user manual for more
1120 * Target descriptions can now describe "compatible" architectures
1121 to indicate that the target can execute applications for a different
1122 architecture in addition to those for the main target architecture.
1123 See the "Target Description Format" section in the user manual for
1126 * Multi-architecture debugging.
1128 GDB now includes general supports for debugging applications on
1129 hybrid systems that use more than one single processor architecture
1130 at the same time. Each such hybrid architecture still requires
1131 specific support to be added. The only hybrid architecture supported
1132 in this version of GDB is the Cell Broadband Engine.
1134 * GDB now supports integrated debugging of Cell/B.E. applications that
1135 use both the PPU and SPU architectures. To enable support for hybrid
1136 Cell/B.E. debugging, you need to configure GDB to support both the
1137 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1138 --enable-targets configure option.
1140 * Non-stop mode debugging.
1142 For some targets, GDB now supports an optional mode of operation in
1143 which you can examine stopped threads while other threads continue
1144 to execute freely. This is referred to as non-stop mode, with the
1145 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1146 section in the user manual for more information.
1148 To be able to support remote non-stop debugging, a remote stub needs
1149 to implement the non-stop mode remote protocol extensions, as
1150 described in the "Remote Non-Stop" section of the user manual. The
1151 GDB remote stub, gdbserver, has been adjusted to support these
1152 extensions on linux targets.
1154 * New commands (for set/show, see "New options" below)
1156 catch syscall [NAME(S) | NUMBER(S)]
1157 Catch system calls. Arguments, which should be names of system
1158 calls or their numbers, mean catch only those syscalls. Without
1159 arguments, every syscall will be caught. When the inferior issues
1160 any of the specified syscalls, GDB will stop and announce the system
1161 call, both when it is called and when its call returns. This
1162 feature is currently available with a native GDB running on the
1163 Linux Kernel, under the following architectures: x86, x86_64,
1164 PowerPC and PowerPC64.
1166 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1168 Search memory for a sequence of bytes.
1170 maint set python print-stack
1171 maint show python print-stack
1172 Show a stack trace when an error is encountered in a Python script.
1175 Invoke CODE by passing it to the Python interpreter.
1180 These allow macros to be defined, undefined, and listed
1184 Show operating system information about processes.
1187 List the inferiors currently under GDB's control.
1190 Switch focus to inferior number NUM.
1193 Detach from inferior number NUM.
1196 Kill inferior number NUM.
1200 set spu stop-on-load
1201 show spu stop-on-load
1202 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1204 set spu auto-flush-cache
1205 show spu auto-flush-cache
1206 Control whether to automatically flush the software-managed cache
1207 during Cell/B.E. debugging.
1209 set sh calling-convention
1210 show sh calling-convention
1211 Control the calling convention used when calling SH target functions.
1214 show debug timestamp
1215 Control display of timestamps with GDB debugging output.
1217 set disassemble-next-line
1218 show disassemble-next-line
1219 Control display of disassembled source lines or instructions when
1222 set remote noack-packet
1223 show remote noack-packet
1224 Set/show the use of remote protocol QStartNoAckMode packet. See above
1225 under "New remote packets."
1227 set remote query-attached-packet
1228 show remote query-attached-packet
1229 Control use of remote protocol `qAttached' (query-attached) packet.
1231 set remote read-siginfo-object
1232 show remote read-siginfo-object
1233 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1236 set remote write-siginfo-object
1237 show remote write-siginfo-object
1238 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1241 set remote reverse-continue
1242 show remote reverse-continue
1243 Control use of remote protocol 'bc' (reverse-continue) packet.
1245 set remote reverse-step
1246 show remote reverse-step
1247 Control use of remote protocol 'bs' (reverse-step) packet.
1249 set displaced-stepping
1250 show displaced-stepping
1251 Control displaced stepping mode. Displaced stepping is a way to
1252 single-step over breakpoints without removing them from the debuggee.
1253 Also known as "out-of-line single-stepping".
1256 show debug displaced
1257 Control display of debugging info for displaced stepping.
1259 maint set internal-error
1260 maint show internal-error
1261 Control what GDB does when an internal error is detected.
1263 maint set internal-warning
1264 maint show internal-warning
1265 Control what GDB does when an internal warning is detected.
1270 Use a wrapper program to launch programs for debugging.
1272 set multiple-symbols (all|ask|cancel)
1273 show multiple-symbols
1274 The value of this variable can be changed to adjust the debugger behavior
1275 when an expression or a breakpoint location contains an ambiguous symbol
1276 name (an overloaded function name, for instance).
1278 set breakpoint always-inserted
1279 show breakpoint always-inserted
1280 Keep breakpoints always inserted in the target, as opposed to inserting
1281 them when resuming the target, and removing them when the target stops.
1282 This option can improve debugger performance on slow remote targets.
1284 set arm fallback-mode (arm|thumb|auto)
1285 show arm fallback-mode
1286 set arm force-mode (arm|thumb|auto)
1288 These commands control how ARM GDB determines whether instructions
1289 are ARM or Thumb. The default for both settings is auto, which uses
1290 the current CPSR value for instructions without symbols; previous
1291 versions of GDB behaved as if "set arm fallback-mode arm".
1293 set disable-randomization
1294 show disable-randomization
1295 Standalone programs run with the virtual address space randomization enabled
1296 by default on some platforms. This option keeps the addresses stable across
1297 multiple debugging sessions.
1301 Control whether other threads are stopped or not when some thread hits
1306 Requests that asynchronous execution is enabled in the target, if available.
1307 In this case, it's possible to resume target in the background, and interact
1308 with GDB while the target is running. "show target-async" displays the
1309 current state of asynchronous execution of the target.
1311 set target-wide-charset
1312 show target-wide-charset
1313 The target-wide-charset is the name of the character set that GDB
1314 uses when printing characters whose type is wchar_t.
1316 set tcp auto-retry (on|off)
1318 set tcp connect-timeout
1319 show tcp connect-timeout
1320 These commands allow GDB to retry failed TCP connections to a remote stub
1321 with a specified timeout period; this is useful if the stub is launched
1322 in parallel with GDB but may not be ready to accept connections immediately.
1324 set libthread-db-search-path
1325 show libthread-db-search-path
1326 Control list of directories which GDB will search for appropriate
1329 set schedule-multiple (on|off)
1330 show schedule-multiple
1331 Allow GDB to resume all threads of all processes or only threads of
1332 the current process.
1336 Use more aggressive caching for accesses to the stack. This improves
1337 performance of remote debugging (particularly backtraces) without
1338 affecting correctness.
1340 set interactive-mode (on|off|auto)
1341 show interactive-mode
1342 Control whether GDB runs in interactive mode (on) or not (off).
1343 When in interactive mode, GDB waits for the user to answer all
1344 queries. Otherwise, GDB does not wait and assumes the default
1345 answer. When set to auto (the default), GDB determines which
1346 mode to use based on the stdin settings.
1351 For program forks, this is replaced by the new more generic `info
1352 inferiors' command. To list checkpoints, you can still use the
1353 `info checkpoints' command, which was an alias for the `info forks'
1357 Replaced by the new `inferior' command. To switch between
1358 checkpoints, you can still use the `restart' command, which was an
1359 alias for the `fork' command.
1362 This is removed, since some targets don't have a notion of
1363 processes. To switch between processes, you can still use the
1364 `inferior' command using GDB's own inferior number.
1367 For program forks, this is replaced by the new more generic `kill
1368 inferior' command. To delete a checkpoint, you can still use the
1369 `delete checkpoint' command, which was an alias for the `delete
1373 For program forks, this is replaced by the new more generic `detach
1374 inferior' command. To detach a checkpoint, you can still use the
1375 `detach checkpoint' command, which was an alias for the `detach
1378 * New native configurations
1380 x86/x86_64 Darwin i[34567]86-*-darwin*
1382 x86_64 MinGW x86_64-*-mingw*
1386 Lattice Mico32 lm32-*
1387 x86 DICOS i[34567]86-*-dicos*
1388 x86_64 DICOS x86_64-*-dicos*
1391 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1392 (mingw32ce) debugging.
1398 These commands were actually not implemented on any target.
1400 *** Changes in GDB 6.8
1402 * New native configurations
1404 NetBSD/hppa hppa*-*netbsd*
1405 Xtensa GNU/Linux xtensa*-*-linux*
1409 NetBSD/hppa hppa*-*-netbsd*
1410 Xtensa GNU/Lunux xtensa*-*-linux*
1412 * Change in command line behavior -- corefiles vs. process ids.
1414 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1415 attaching to process NUMBER fails, GDB no longer attempts to open a
1416 core file named NUMBER. Attaching to a program using the -c option
1417 is no longer supported. Instead, use the '-p' or '--pid' options.
1419 * GDB can now be built as a native debugger for debugging Windows x86
1420 (mingw32) Portable Executable (PE) programs.
1422 * Pending breakpoints no longer change their number when their address
1425 * GDB now supports breakpoints with multiple locations,
1426 including breakpoints on C++ constructors, inside C++ templates,
1427 and in inlined functions.
1429 * GDB's ability to debug optimized code has been improved. GDB more
1430 accurately identifies function bodies and lexical blocks that occupy
1431 more than one contiguous range of addresses.
1433 * Target descriptions can now describe registers for PowerPC.
1435 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1436 registers on PowerPC targets.
1438 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1439 targets even when the libthread_db library is not available.
1441 * The GDB remote stub, gdbserver, now supports the new file transfer
1442 commands (remote put, remote get, and remote delete).
1444 * The GDB remote stub, gdbserver, now supports run and attach in
1445 extended-remote mode.
1447 * hppa*64*-*-hpux11* target broken
1448 The debugger is unable to start a program and fails with the following
1449 error: "Error trying to get information about dynamic linker".
1450 The gdb-6.7 release is also affected.
1452 * GDB now supports the --enable-targets= configure option to allow
1453 building a single GDB executable that supports multiple remote
1454 target architectures.
1456 * GDB now supports debugging C and C++ programs which use the
1457 Decimal Floating Point extension. In addition, the PowerPC target
1458 now has a set of pseudo-registers to inspect decimal float values
1459 stored in two consecutive float registers.
1461 * The -break-insert MI command can optionally create pending
1464 * Improved support for debugging Ada
1465 Many improvements to the Ada language support have been made. These
1467 - Better support for Ada2005 interface types
1468 - Improved handling of arrays and slices in general
1469 - Better support for Taft-amendment types
1470 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1472 - Improved command completion in Ada
1475 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1480 set print frame-arguments (all|scalars|none)
1481 show print frame-arguments
1482 The value of this variable can be changed to control which argument
1483 values should be printed by the debugger when displaying a frame.
1488 Transfer files to and from a remote target, and delete remote files.
1495 Transfer files to and from a remote target, and delete remote files.
1497 * New remote packets
1504 Open, close, read, write, and delete files on the remote system.
1507 Attach to an existing process on the remote system, in extended-remote
1511 Run a new process on the remote system, in extended-remote mode.
1513 *** Changes in GDB 6.7
1515 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1516 bfd, libiberty and opcodes, as revealed by static analysis donated by
1517 Coverity, Inc. (http://scan.coverity.com).
1519 * When looking up multiply-defined global symbols, GDB will now prefer the
1520 symbol definition in the current shared library if it was built using the
1521 -Bsymbolic linker option.
1523 * When the Text User Interface (TUI) is not configured, GDB will now
1524 recognize the -tui command-line option and print a message that the TUI
1527 * The GDB remote stub, gdbserver, now has lower overhead for high
1528 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1530 * GDB for MIPS targets now autodetects whether a remote target provides
1531 32-bit or 64-bit register values.
1533 * Support for C++ member pointers has been improved.
1535 * GDB now understands XML target descriptions, which specify the
1536 target's overall architecture. GDB can read a description from
1537 a local file or over the remote serial protocol.
1539 * Vectors of single-byte data use a new integer type which is not
1540 automatically displayed as character or string data.
1542 * The /s format now works with the print command. It displays
1543 arrays of single-byte integers and pointers to single-byte integers
1546 * Target descriptions can now describe target-specific registers,
1547 for architectures which have implemented the support (currently
1548 only ARM, M68K, and MIPS).
1550 * GDB and the GDB remote stub, gdbserver, now support the XScale
1553 * The GDB remote stub, gdbserver, has been updated to support
1554 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1555 has been rewritten to use the standard GDB remote protocol.
1557 * GDB can now step into C++ functions which are called through thunks.
1559 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1561 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1562 layout. It also supports a TextSeg= and DataSeg= response when only
1563 segment base addresses (rather than offsets) are available.
1565 * The /i format now outputs any trailing branch delay slot instructions
1566 immediately following the last instruction within the count specified.
1568 * The GDB remote protocol "T" stop reply packet now supports a
1569 "library" response. Combined with the new "qXfer:libraries:read"
1570 packet, this response allows GDB to debug shared libraries on targets
1571 where the operating system manages the list of loaded libraries (e.g.
1572 Windows and SymbianOS).
1574 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1575 (DLLs) on Windows and Windows CE targets.
1577 * GDB now supports a faster verification that a .debug file matches its binary
1578 according to its build-id signature, if the signature is present.
1584 Enable or disable hardware flow control (RTS/CTS) on the serial port
1585 when debugging using remote targets.
1587 set mem inaccessible-by-default
1588 show mem inaccessible-by-default
1589 If the target supplies a memory map, for instance via the remote
1590 protocol's "qXfer:memory-map:read" packet, setting this variable
1591 prevents GDB from accessing memory outside the memory map. This
1592 is useful for targets with memory mapped registers or which react
1593 badly to accesses of unmapped address space.
1595 set breakpoint auto-hw
1596 show breakpoint auto-hw
1597 If the target supplies a memory map, for instance via the remote
1598 protocol's "qXfer:memory-map:read" packet, setting this variable
1599 lets GDB use hardware breakpoints automatically for memory regions
1600 where it can not use software breakpoints. This covers both the
1601 "break" command and internal breakpoints used for other commands
1602 including "next" and "finish".
1605 catch exception unhandled
1606 Stop the program execution when Ada exceptions are raised.
1609 Stop the program execution when an Ada assertion failed.
1613 Set an alternate system root for target files. This is a more
1614 general version of "set solib-absolute-prefix", which is now
1615 an alias to "set sysroot".
1618 Provide extended SPU facility status information. This set of
1619 commands is available only when debugging the Cell/B.E. SPU
1622 * New native configurations
1624 OpenBSD/sh sh*-*openbsd*
1627 unset tdesc filename
1629 Use the specified local file as an XML target description, and do
1630 not query the target for its built-in description.
1634 OpenBSD/sh sh*-*-openbsd*
1635 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1636 Toshiba Media Processor mep-elf
1638 * New remote packets
1641 Ignore the specified signals; pass them directly to the debugged program
1642 without stopping other threads or reporting them to GDB.
1644 qXfer:features:read:
1645 Read an XML target description from the target, which describes its
1650 Read or write contents of an spufs file on the target system. These
1651 packets are available only on the Cell/B.E. SPU architecture.
1653 qXfer:libraries:read:
1654 Report the loaded shared libraries. Combined with new "T" packet
1655 response, this packet allows GDB to debug shared libraries on
1656 targets where the operating system manages the list of loaded
1657 libraries (e.g. Windows and SymbianOS).
1661 Support for these obsolete configurations has been removed.
1669 i[34567]86-*-lynxos*
1670 i[34567]86-*-netware*
1671 i[34567]86-*-sco3.2v5*
1672 i[34567]86-*-sco3.2v4*
1674 i[34567]86-*-sysv4.2*
1677 i[34567]86-*-unixware2*
1678 i[34567]86-*-unixware*
1687 * Other removed features
1694 Various m68k-only ROM monitors.
1701 Various Renesas ROM monitors and debugging interfaces for SH and
1706 Support for a Macraigor serial interface to on-chip debugging.
1707 GDB does not directly support the newer parallel or USB
1712 A debug information format. The predecessor to DWARF 2 and
1713 DWARF 3, which are still supported.
1715 Support for the HP aCC compiler on HP-UX/PA-RISC
1717 SOM-encapsulated symbolic debugging information, automatic
1718 invocation of pxdb, and the aCC custom C++ ABI. This does not
1719 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1720 with aCC can still be debugged on an assembly level.
1722 MIPS ".pdr" sections
1724 A MIPS-specific format used to describe stack frame layout
1725 in debugging information.
1729 GDB could work with an older version of Guile to debug
1730 the interpreter and Scheme programs running in it.
1732 set mips stack-arg-size
1733 set mips saved-gpreg-size
1735 Use "set mips abi" to control parameter passing for MIPS.
1737 *** Changes in GDB 6.6
1742 Cell Broadband Engine SPU spu-elf
1744 * GDB can now be configured as a cross-debugger targeting native Windows
1745 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1746 running on a Windows system over TCP/IP to debug Windows programs.
1748 * The GDB remote stub, gdbserver, has been updated to support Windows and
1749 Cygwin debugging. Both single-threaded and multi-threaded programs are
1752 * The "set trust-readonly-sections" command works again. This command was
1753 broken in GDB 6.3, 6.4, and 6.5.
1755 * The "load" command now supports writing to flash memory, if the remote
1756 stub provides the required support.
1758 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1759 longer requires symbolic debug information (e.g. DWARF-2).
1764 unset substitute-path
1765 show substitute-path
1766 Manage a list of substitution rules that GDB uses to rewrite the name
1767 of the directories where the sources are located. This can be useful
1768 for instance when the sources were moved to a different location
1769 between compilation and debugging.
1773 Print each CLI command as it is executed. Each command is prefixed with
1774 a number of `+' symbols representing the nesting depth.
1775 The source command now has a `-v' option to enable the same feature.
1779 The ARM Demon monitor support (RDP protocol, "target rdp").
1781 Kernel Object Display, an embedded debugging feature which only worked with
1782 an obsolete version of Cisco IOS.
1784 The 'set download-write-size' and 'show download-write-size' commands.
1786 * New remote packets
1789 Tell a stub about GDB client features, and request remote target features.
1790 The first feature implemented is PacketSize, which allows the target to
1791 specify the size of packets it can handle - to minimize the number of
1792 packets required and improve performance when connected to a remote
1796 Fetch an OS auxilliary vector from the remote stub. This packet is a
1797 more efficient replacement for qPart:auxv:read.
1799 qXfer:memory-map:read:
1800 Fetch a memory map from the remote stub, including information about
1801 RAM, ROM, and flash memory devices.
1806 Erase and program a flash memory device.
1808 * Removed remote packets
1811 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1812 used it, and only gdbserver implemented it.
1814 *** Changes in GDB 6.5
1818 Renesas M32C/M16C m32c-elf
1820 Morpho Technologies ms1 ms1-elf
1824 init-if-undefined Initialize a convenience variable, but
1825 only if it doesn't already have a value.
1827 The following commands are presently only implemented for native GNU/Linux:
1829 checkpoint Save a snapshot of the program state.
1831 restart <n> Return the program state to a
1832 previously saved state.
1834 info checkpoints List currently saved checkpoints.
1836 delete-checkpoint <n> Delete a previously saved checkpoint.
1838 set|show detach-on-fork Tell gdb whether to detach from a newly
1839 forked process, or to keep debugging it.
1841 info forks List forks of the user program that
1842 are available to be debugged.
1844 fork <n> Switch to debugging one of several
1845 forks of the user program that are
1846 available to be debugged.
1848 delete-fork <n> Delete a fork from the list of forks
1849 that are available to be debugged (and
1850 kill the forked process).
1852 detach-fork <n> Delete a fork from the list of forks
1853 that are available to be debugged (and
1854 allow the process to continue).
1858 Morpho Technologies ms2 ms1-elf
1860 * Improved Windows host support
1862 GDB now builds as a cross debugger hosted on i686-mingw32, including
1863 native console support, and remote communications using either
1864 network sockets or serial ports.
1866 * Improved Modula-2 language support
1868 GDB can now print most types in the Modula-2 syntax. This includes:
1869 basic types, set types, record types, enumerated types, range types,
1870 pointer types and ARRAY types. Procedure var parameters are correctly
1871 printed and hexadecimal addresses and character constants are also
1872 written in the Modula-2 syntax. Best results can be obtained by using
1873 GNU Modula-2 together with the -gdwarf-2 command line option.
1877 The ARM rdi-share module.
1879 The Netware NLM debug server.
1881 *** Changes in GDB 6.4
1883 * New native configurations
1885 OpenBSD/arm arm*-*-openbsd*
1886 OpenBSD/mips64 mips64-*-openbsd*
1890 Morpho Technologies ms1 ms1-elf
1892 * New command line options
1894 --batch-silent As for --batch, but totally silent.
1895 --return-child-result The debugger will exist with the same value
1896 the child (debugged) program exited with.
1897 --eval-command COMMAND, -ex COMMAND
1898 Execute a single GDB CLI command. This may be
1899 specified multiple times and in conjunction
1900 with the --command (-x) option.
1902 * Deprecated commands removed
1904 The following commands, that were deprecated in 2000, have been
1908 set|show arm disassembly-flavor set|show arm disassembler
1909 othernames set arm disassembler
1910 set|show remotedebug set|show debug remote
1911 set|show archdebug set|show debug arch
1912 set|show eventdebug set|show debug event
1915 * New BSD user-level threads support
1917 It is now possible to debug programs using the user-level threads
1918 library on OpenBSD and FreeBSD. Currently supported (target)
1921 FreeBSD/amd64 x86_64-*-freebsd*
1922 FreeBSD/i386 i386-*-freebsd*
1923 OpenBSD/i386 i386-*-openbsd*
1925 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1926 are not yet supported.
1928 * New support for Matsushita MN10300 w/sim added
1929 (Work in progress). mn10300-elf.
1931 * REMOVED configurations and files
1933 VxWorks and the XDR protocol *-*-vxworks
1934 Motorola MCORE mcore-*-*
1935 National Semiconductor NS32000 ns32k-*-*
1937 * New "set print array-indexes" command
1939 After turning this setting "on", GDB prints the index of each element
1940 when displaying arrays. The default is "off" to preserve the previous
1943 * VAX floating point support
1945 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1947 * User-defined command support
1949 In addition to using $arg0..$arg9 for argument passing, it is now possible
1950 to use $argc to determine now many arguments have been passed. See the
1951 section on user-defined commands in the user manual for more information.
1953 *** Changes in GDB 6.3:
1955 * New command line option
1957 GDB now accepts -l followed by a number to set the timeout for remote
1960 * GDB works with GCC -feliminate-dwarf2-dups
1962 GDB now supports a more compact representation of DWARF-2 debug
1963 information using DW_FORM_ref_addr references. These are produced
1964 by GCC with the option -feliminate-dwarf2-dups and also by some
1965 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1966 to use -feliminate-dwarf2-dups.
1968 * Internationalization
1970 When supported by the host system, GDB will be built with
1971 internationalization (libintl). The task of marking up the sources is
1972 continued, we're looking forward to our first translation.
1976 Initial support for debugging programs compiled with the GNAT
1977 implementation of the Ada programming language has been integrated
1978 into GDB. In this release, support is limited to expression evaluation.
1980 * New native configurations
1982 GNU/Linux/m32r m32r-*-linux-gnu
1986 GDB's remote protocol now includes support for the 'p' packet. This
1987 packet is used to fetch individual registers from a remote inferior.
1989 * END-OF-LIFE registers[] compatibility module
1991 GDB's internal register infrastructure has been completely rewritten.
1992 The new infrastructure making possible the implementation of key new
1993 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1996 GDB 6.3 will be the last release to include the the registers[]
1997 compatibility module that allowed out-of-date configurations to
1998 continue to work. This change directly impacts the following
2008 powerpc bdm protocol
2010 Unless there is activity to revive these configurations, they will be
2011 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2013 * OBSOLETE configurations and files
2015 Configurations that have been declared obsolete in this release have
2016 been commented out. Unless there is activity to revive these
2017 configurations, the next release of GDB will have their sources
2018 permanently REMOVED.
2027 *** Changes in GDB 6.2.1:
2029 * MIPS `break main; run' gave an heuristic-fence-post warning
2031 When attempting to run even a simple program, a warning about
2032 heuristic-fence-post being hit would be reported. This problem has
2035 * MIPS IRIX 'long double' crashed GDB
2037 When examining a long double variable, GDB would get a segmentation
2038 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2039 IRIX long double values).
2043 A bug in the VAX stack code was causing problems with the "next"
2044 command. This problem has been fixed.
2046 *** Changes in GDB 6.2:
2048 * Fix for ``many threads''
2050 On GNU/Linux systems that use the NPTL threads library, a program
2051 rapidly creating and deleting threads would confuse GDB leading to the
2054 ptrace: No such process.
2055 thread_db_get_info: cannot get thread info: generic error
2057 This problem has been fixed.
2059 * "-async" and "-noasync" options removed.
2061 Support for the broken "-noasync" option has been removed (it caused
2064 * New ``start'' command.
2066 This command runs the program until the begining of the main procedure.
2068 * New BSD Kernel Data Access Library (libkvm) interface
2070 Using ``target kvm'' it is now possible to debug kernel core dumps and
2071 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2072 platforms. Currently supported (native-only) configurations are:
2074 FreeBSD/amd64 x86_64-*-freebsd*
2075 FreeBSD/i386 i?86-*-freebsd*
2076 NetBSD/i386 i?86-*-netbsd*
2077 NetBSD/m68k m68*-*-netbsd*
2078 NetBSD/sparc sparc-*-netbsd*
2079 OpenBSD/amd64 x86_64-*-openbsd*
2080 OpenBSD/i386 i?86-*-openbsd*
2081 OpenBSD/m68k m68*-openbsd*
2082 OpenBSD/sparc sparc-*-openbsd*
2084 * Signal trampoline code overhauled
2086 Many generic problems with GDB's signal handling code have been fixed.
2087 These include: backtraces through non-contiguous stacks; recognition
2088 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2089 call; backtrace through a signal trampoline; step into and out of
2090 signal handlers; and single-stepping in the signal trampoline.
2092 Please note that kernel bugs are a limiting factor here. These
2093 features have been shown to work on an s390 GNU/Linux system that
2094 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2096 * Cygwin support for DWARF 2 added.
2098 * New native configurations
2100 GNU/Linux/hppa hppa*-*-linux*
2101 OpenBSD/hppa hppa*-*-openbsd*
2102 OpenBSD/m68k m68*-*-openbsd*
2103 OpenBSD/m88k m88*-*-openbsd*
2104 OpenBSD/powerpc powerpc-*-openbsd*
2105 NetBSD/vax vax-*-netbsd*
2106 OpenBSD/vax vax-*-openbsd*
2108 * END-OF-LIFE frame compatibility module
2110 GDB's internal frame infrastructure has been completely rewritten.
2111 The new infrastructure making it possible to support key new features
2112 including DWARF 2 Call Frame Information. To aid in the task of
2113 migrating old configurations to this new infrastructure, a
2114 compatibility module, that allowed old configurations to continue to
2115 work, was also included.
2117 GDB 6.2 will be the last release to include this frame compatibility
2118 module. This change directly impacts the following configurations:
2128 Unless there is activity to revive these configurations, they will be
2129 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2131 * REMOVED configurations and files
2133 Sun 3, running SunOS 3 m68*-*-sunos3*
2134 Sun 3, running SunOS 4 m68*-*-sunos4*
2135 Sun 2, running SunOS 3 m68000-*-sunos3*
2136 Sun 2, running SunOS 4 m68000-*-sunos4*
2137 Motorola 680x0 running LynxOS m68*-*-lynxos*
2138 AT&T 3b1/Unix pc m68*-att-*
2139 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2140 decstation mips-dec-* mips-little-*
2141 riscos mips-*-riscos* mips-*-sysv*
2142 sonymips mips-sony-*
2143 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2145 *** Changes in GDB 6.1.1:
2147 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2149 The TUI (Text-mode User Interface) is now built as part of a default
2150 GDB configuration. It is enabled by either selecting the TUI with the
2151 command line option "-i=tui" or by running the separate "gdbtui"
2152 program. For more information on the TUI, see the manual "Debugging
2155 * Pending breakpoint support (also included in GDB 6.1)
2157 Support has been added to allow you to specify breakpoints in shared
2158 libraries that have not yet been loaded. If a breakpoint location
2159 cannot be found, and the "breakpoint pending" option is set to auto,
2160 GDB queries you if you wish to make the breakpoint pending on a future
2161 shared-library load. If and when GDB resolves the breakpoint symbol,
2162 the pending breakpoint is removed as one or more regular breakpoints
2165 Pending breakpoints are very useful for GCJ Java debugging.
2167 * Fixed ISO-C build problems
2169 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2170 non ISO-C code that stopped them being built using a more strict ISO-C
2171 compiler (e.g., IBM's C compiler).
2173 * Fixed build problem on IRIX 5
2175 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2176 wasn't able to compile compile on an IRIX 5 system.
2178 * Added execute permission to gdb/gdbserver/configure
2180 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2181 permission. This bug would cause configure to fail on a number of
2182 systems (Solaris, IRIX). Ref: server/519.
2184 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2186 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2187 has been updated to use constant array sizes.
2189 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2191 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2192 its generated DWARF Call Frame Info. This encoding was causing GDB to
2193 panic, that panic has been fixed. Ref: gdb/1628.
2195 * Fixed a problem when examining parameters in shared library code.
2197 When examining parameters in optimized shared library code generated
2198 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2199 not available''. GDB now correctly displays the variable's value.
2201 *** Changes in GDB 6.1:
2203 * Removed --with-mmalloc
2205 Support for the mmalloc memory manager has been removed, as it
2206 conflicted with the internal gdb byte cache.
2208 * Changes in AMD64 configurations
2210 The AMD64 target now includes the %cs and %ss registers. As a result
2211 the AMD64 remote protocol has changed; this affects the floating-point
2212 and SSE registers. If you rely on those registers for your debugging,
2213 you should upgrade gdbserver on the remote side.
2215 * Revised SPARC target
2217 The SPARC target has been completely revised, incorporating the
2218 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2219 support for LynxOS and SunOS 4 has been dropped. Calling functions
2220 from within GDB on operating systems with a non-executable stack
2221 (Solaris, OpenBSD) now works.
2225 GDB has a new C++ demangler which does a better job on the mangled
2226 names generated by current versions of g++. It also runs faster, so
2227 with this and other changes gdb should now start faster on large C++
2230 * DWARF 2 Location Expressions
2232 GDB support for location expressions has been extended to support function
2233 arguments and frame bases. Older versions of GDB could crash when they
2236 * C++ nested types and namespaces
2238 GDB's support for nested types and namespaces in C++ has been
2239 improved, especially if you use the DWARF 2 debugging format. (This
2240 is the default for recent versions of GCC on most platforms.)
2241 Specifically, if you have a class "Inner" defined within a class or
2242 namespace "Outer", then GDB realizes that the class's name is
2243 "Outer::Inner", not simply "Inner". This should greatly reduce the
2244 frequency of complaints about not finding RTTI symbols. In addition,
2245 if you are stopped at inside of a function defined within a namespace,
2246 GDB modifies its name lookup accordingly.
2248 * New native configurations
2250 NetBSD/amd64 x86_64-*-netbsd*
2251 OpenBSD/amd64 x86_64-*-openbsd*
2252 OpenBSD/alpha alpha*-*-openbsd*
2253 OpenBSD/sparc sparc-*-openbsd*
2254 OpenBSD/sparc64 sparc64-*-openbsd*
2256 * New debugging protocols
2258 M32R with SDI protocol m32r-*-elf*
2260 * "set prompt-escape-char" command deleted.
2262 The command "set prompt-escape-char" has been deleted. This command,
2263 and its very obscure effet on GDB's prompt, was never documented,
2264 tested, nor mentioned in the NEWS file.
2266 * OBSOLETE configurations and files
2268 Configurations that have been declared obsolete in this release have
2269 been commented out. Unless there is activity to revive these
2270 configurations, the next release of GDB will have their sources
2271 permanently REMOVED.
2273 Sun 3, running SunOS 3 m68*-*-sunos3*
2274 Sun 3, running SunOS 4 m68*-*-sunos4*
2275 Sun 2, running SunOS 3 m68000-*-sunos3*
2276 Sun 2, running SunOS 4 m68000-*-sunos4*
2277 Motorola 680x0 running LynxOS m68*-*-lynxos*
2278 AT&T 3b1/Unix pc m68*-att-*
2279 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2280 decstation mips-dec-* mips-little-*
2281 riscos mips-*-riscos* mips-*-sysv*
2282 sonymips mips-sony-*
2283 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2285 * REMOVED configurations and files
2287 SGI Irix-4.x mips-sgi-irix4 or iris4
2288 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2289 Z8000 simulator z8k-zilog-none or z8ksim
2290 Matsushita MN10200 w/simulator mn10200-*-*
2291 H8/500 simulator h8500-hitachi-hms or h8500hms
2292 HP/PA running BSD hppa*-*-bsd*
2293 HP/PA running OSF/1 hppa*-*-osf*
2294 HP/PA Pro target hppa*-*-pro*
2295 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2296 386BSD i[3456]86-*-bsd*
2297 Sequent family i[3456]86-sequent-sysv4*
2298 i[3456]86-sequent-sysv*
2299 i[3456]86-sequent-bsd*
2300 SPARC running LynxOS sparc-*-lynxos*
2301 SPARC running SunOS 4 sparc-*-sunos4*
2302 Tsqware Sparclet sparclet-*-*
2303 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2305 *** Changes in GDB 6.0:
2309 Support for debugging the Objective-C programming language has been
2310 integrated into GDB.
2312 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2314 DWARF 2's Call Frame Information makes available compiler generated
2315 information that more exactly describes the program's run-time stack.
2316 By using this information, GDB is able to provide more robust stack
2319 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2320 have been updated to use a new backtrace mechanism which includes
2321 DWARF 2 CFI support.
2325 GDB's remote protocol has been extended to include support for hosted
2326 file I/O (where the remote target uses GDB's file system). See GDB's
2327 remote protocol documentation for details.
2329 * All targets using the new architecture framework.
2331 All of GDB's targets have been updated to use the new internal
2332 architecture framework. The way is now open for future GDB releases
2333 to include cross-architecture native debugging support (i386 on amd64,
2336 * GNU/Linux's Thread Local Storage (TLS)
2338 GDB now includes support for for the GNU/Linux implementation of
2339 per-thread variables.
2341 * GNU/Linux's Native POSIX Thread Library (NPTL)
2343 GDB's thread code has been updated to work with either the new
2344 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2346 * Separate debug info.
2348 GDB, in conjunction with BINUTILS, now supports a mechanism for
2349 automatically loading debug information from a separate file. Instead
2350 of shipping full debug and non-debug versions of system libraries,
2351 system integrators can now instead ship just the stripped libraries
2352 and optional debug files.
2354 * DWARF 2 Location Expressions
2356 DWARF 2 Location Expressions allow the compiler to more completely
2357 describe the location of variables (even in optimized code) to the
2360 GDB now includes preliminary support for location expressions (support
2361 for DW_OP_piece is still missing).
2365 A number of long standing bugs that caused GDB to die while starting a
2366 Java application have been fixed. GDB's Java support is now
2367 considered "useable".
2369 * GNU/Linux support for fork, vfork, and exec.
2371 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2372 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2375 * GDB supports logging output to a file
2377 There are two new commands, "set logging" and "show logging", which can be
2378 used to capture GDB's output to a file.
2380 * The meaning of "detach" has changed for gdbserver
2382 The "detach" command will now resume the application, as documented. To
2383 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2386 * d10v, m68hc11 `regs' command deprecated
2388 The `info registers' command has been updated so that it displays the
2389 registers using a format identical to the old `regs' command.
2393 A new command, "maint set profile on/off", has been added. This command can
2394 be used to enable or disable profiling while running GDB, to profile a
2395 session or a set of commands. In addition there is a new configure switch,
2396 "--enable-profiling", which will cause GDB to be compiled with profiling
2397 data, for more informative profiling results.
2399 * Default MI syntax changed to "mi2".
2401 The default MI (machine interface) syntax, enabled by the command line
2402 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2403 "mi1", can be enabled by specifying the option "-i=mi1".
2405 Support for the original "mi0" syntax (included in GDB 5.0) has been
2408 Fix for gdb/192: removed extraneous space when displaying frame level.
2409 Fix for gdb/672: update changelist is now output in mi list format.
2410 Fix for gdb/702: a -var-assign that updates the value now shows up
2411 in a subsequent -var-update.
2413 * New native configurations.
2415 FreeBSD/amd64 x86_64-*-freebsd*
2417 * Multi-arched targets.
2419 HP/PA HPUX11 hppa*-*-hpux*
2420 Renesas M32R/D w/simulator m32r-*-elf*
2422 * OBSOLETE configurations and files
2424 Configurations that have been declared obsolete in this release have
2425 been commented out. Unless there is activity to revive these
2426 configurations, the next release of GDB will have their sources
2427 permanently REMOVED.
2429 Z8000 simulator z8k-zilog-none or z8ksim
2430 Matsushita MN10200 w/simulator mn10200-*-*
2431 H8/500 simulator h8500-hitachi-hms or h8500hms
2432 HP/PA running BSD hppa*-*-bsd*
2433 HP/PA running OSF/1 hppa*-*-osf*
2434 HP/PA Pro target hppa*-*-pro*
2435 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2436 Sequent family i[3456]86-sequent-sysv4*
2437 i[3456]86-sequent-sysv*
2438 i[3456]86-sequent-bsd*
2439 Tsqware Sparclet sparclet-*-*
2440 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2442 * REMOVED configurations and files
2445 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2446 IBM AIX PS/2 i[3456]86-*-aix
2447 i386 running Mach 3.0 i[3456]86-*-mach3*
2448 i386 running Mach i[3456]86-*-mach*
2449 i386 running OSF/1 i[3456]86-*osf1mk*
2450 HP/Apollo 68k Family m68*-apollo*-sysv*,
2452 m68*-hp-bsd*, m68*-hp-hpux*
2453 Argonaut Risc Chip (ARC) arc-*-*
2454 Mitsubishi D30V d30v-*-*
2455 Fujitsu FR30 fr30-*-elf*
2456 OS/9000 i[34]86-*-os9k
2457 I960 with MON960 i960-*-coff
2459 * MIPS $fp behavior changed
2461 The convenience variable $fp, for the MIPS, now consistently returns
2462 the address of the current frame's base. Previously, depending on the
2463 context, $fp could refer to either $sp or the current frame's base
2464 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2465 The GNU Source-Level Debugger''.
2467 *** Changes in GDB 5.3:
2469 * GNU/Linux shared library multi-threaded performance improved.
2471 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2472 `/proc', in preference to `ptrace' for memory reads. This may result
2473 in an improvement in the start-up time of multi-threaded, shared
2474 library applications when run under GDB. One GDB user writes: ``loads
2475 shared libs like mad''.
2477 * ``gdbserver'' now supports multi-threaded applications on some targets
2479 Support for debugging multi-threaded applications which use
2480 the GNU/Linux LinuxThreads package has been added for
2481 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2482 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2484 * GDB now supports C/C++ preprocessor macros.
2486 GDB now expands preprocessor macro invocations in C/C++ expressions,
2487 and provides various commands for showing macro definitions and how
2490 The new command `macro expand EXPRESSION' expands any macro
2491 invocations in expression, and shows the result.
2493 The new command `show macro MACRO-NAME' shows the definition of the
2494 macro named MACRO-NAME, and where it was defined.
2496 Most compilers don't include information about macros in the debugging
2497 information by default. In GCC 3.1, for example, you need to compile
2498 your program with the options `-gdwarf-2 -g3'. If the macro
2499 information is present in the executable, GDB will read it.
2501 * Multi-arched targets.
2503 DEC Alpha (partial) alpha*-*-*
2504 DEC VAX (partial) vax-*-*
2506 National Semiconductor NS32000 (partial) ns32k-*-*
2507 Motorola 68000 (partial) m68k-*-*
2508 Motorola MCORE mcore-*-*
2512 Fujitsu FRV architecture added by Red Hat frv*-*-*
2515 * New native configurations
2517 Alpha NetBSD alpha*-*-netbsd*
2518 SH NetBSD sh*-*-netbsdelf*
2519 MIPS NetBSD mips*-*-netbsd*
2520 UltraSPARC NetBSD sparc64-*-netbsd*
2522 * OBSOLETE configurations and files
2524 Configurations that have been declared obsolete in this release have
2525 been commented out. Unless there is activity to revive these
2526 configurations, the next release of GDB will have their sources
2527 permanently REMOVED.
2529 Mitsubishi D30V d30v-*-*
2530 OS/9000 i[34]86-*-os9k
2531 IBM AIX PS/2 i[3456]86-*-aix
2532 Fujitsu FR30 fr30-*-elf*
2533 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2534 Argonaut Risc Chip (ARC) arc-*-*
2535 i386 running Mach 3.0 i[3456]86-*-mach3*
2536 i386 running Mach i[3456]86-*-mach*
2537 i386 running OSF/1 i[3456]86-*osf1mk*
2538 HP/Apollo 68k Family m68*-apollo*-sysv*,
2540 m68*-hp-bsd*, m68*-hp-hpux*
2541 I960 with MON960 i960-*-coff
2543 * OBSOLETE languages
2545 CHILL, a Pascal like language used by telecommunications companies.
2547 * REMOVED configurations and files
2549 AMD 29k family via UDI a29k-amd-udi, udi29k
2550 A29K VxWorks a29k-*-vxworks
2551 AMD 29000 embedded, using EBMON a29k-none-none
2552 AMD 29000 embedded with COFF a29k-none-coff
2553 AMD 29000 embedded with a.out a29k-none-aout
2555 testsuite/gdb.hp/gdb.threads-hp/ directory
2557 * New command "set max-user-call-depth <nnn>"
2559 This command allows the user to limit the call depth of user-defined
2560 commands. The default is 1024.
2562 * Changes in FreeBSD/i386 native debugging.
2564 Support for the "generate-core-file" has been added.
2566 * New commands "dump", "append", and "restore".
2568 These commands allow data to be copied from target memory
2569 to a bfd-format or binary file (dump and append), and back
2570 from a file into memory (restore).
2572 * Improved "next/step" support on multi-processor Alpha Tru64.
2574 The previous single-step mechanism could cause unpredictable problems,
2575 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2576 of a software single-step mechanism prevents this.
2578 *** Changes in GDB 5.2.1:
2586 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2587 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2588 Fix, by Joel Brobecker imported from mainline.
2590 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2591 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2592 Fix, by Fred Fish, imported from mainline.
2594 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2595 Surprisingly enough, it works now.
2596 By Michal Ludvig, imported from mainline.
2598 i386 hardware watchpoint support:
2599 avoid misses on second run for some targets.
2600 By Pierre Muller, imported from mainline.
2602 *** Changes in GDB 5.2:
2604 * New command "set trust-readonly-sections on[off]".
2606 This command is a hint that tells gdb that read-only sections
2607 really are read-only (ie. that their contents will not change).
2608 In this mode, gdb will go to the object file rather than the
2609 target to read memory from read-only sections (such as ".text").
2610 This can be a significant performance improvement on some
2611 (notably embedded) targets.
2613 * New command "generate-core-file" (or "gcore").
2615 This new gdb command allows the user to drop a core file of the child
2616 process state at any time. So far it's been implemented only for
2617 GNU/Linux and Solaris, but should be relatively easily ported to other
2618 hosts. Argument is core file name (defaults to core.<pid>).
2620 * New command line option
2622 GDB now accepts --pid or -p followed by a process id.
2624 * Change in command line behavior -- corefiles vs. process ids.
2626 There is a subtle behavior in the way in which GDB handles
2627 command line arguments. The first non-flag argument is always
2628 a program to debug, but the second non-flag argument may either
2629 be a corefile or a process id. Previously, GDB would attempt to
2630 open the second argument as a corefile, and if that failed, would
2631 issue a superfluous error message and then attempt to attach it as
2632 a process. Now, if the second argument begins with a non-digit,
2633 it will be treated as a corefile. If it begins with a digit,
2634 GDB will attempt to attach it as a process, and if no such process
2635 is found, will then attempt to open it as a corefile.
2637 * Changes in ARM configurations.
2639 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2640 configuration is fully multi-arch.
2642 * New native configurations
2644 ARM NetBSD arm*-*-netbsd*
2645 x86 OpenBSD i[3456]86-*-openbsd*
2646 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2647 Sparc64 running FreeBSD sparc64-*-freebsd*
2651 Sanyo XStormy16 xstormy16-elf
2653 * OBSOLETE configurations and files
2655 Configurations that have been declared obsolete in this release have
2656 been commented out. Unless there is activity to revive these
2657 configurations, the next release of GDB will have their sources
2658 permanently REMOVED.
2660 AMD 29k family via UDI a29k-amd-udi, udi29k
2661 A29K VxWorks a29k-*-vxworks
2662 AMD 29000 embedded, using EBMON a29k-none-none
2663 AMD 29000 embedded with COFF a29k-none-coff
2664 AMD 29000 embedded with a.out a29k-none-aout
2666 testsuite/gdb.hp/gdb.threads-hp/ directory
2668 * REMOVED configurations and files
2670 TI TMS320C80 tic80-*-*
2672 PowerPC Solaris powerpcle-*-solaris*
2673 PowerPC Windows NT powerpcle-*-cygwin32
2674 PowerPC Netware powerpc-*-netware*
2675 Harris/CXUX m88k m88*-harris-cxux*
2676 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2677 ns32k-utek-sysv* ns32k-utek-*
2678 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2679 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2680 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2681 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2682 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2684 * Changes to command line processing
2686 The new `--args' feature can be used to specify command-line arguments
2687 for the inferior from gdb's command line.
2689 * Changes to key bindings
2691 There is a new `operate-and-get-next' function bound to `C-o'.
2693 *** Changes in GDB 5.1.1
2695 Fix compile problem on DJGPP.
2697 Fix a problem with floating-point registers on the i386 being
2700 Fix to stop GDB crashing on .debug_str debug info.
2702 Numerous documentation fixes.
2704 Numerous testsuite fixes.
2706 *** Changes in GDB 5.1:
2708 * New native configurations
2710 Alpha FreeBSD alpha*-*-freebsd*
2711 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2712 MIPS GNU/Linux mips*-*-linux*
2713 MIPS SGI Irix 6.x mips*-sgi-irix6*
2714 ia64 AIX ia64-*-aix*
2715 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2719 Motorola 68HC11 and 68HC12 m68hc11-elf
2721 UltraSparc running GNU/Linux sparc64-*-linux*
2723 * OBSOLETE configurations and files
2725 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2726 Harris/CXUX m88k m88*-harris-cxux*
2727 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2728 ns32k-utek-sysv* ns32k-utek-*
2729 TI TMS320C80 tic80-*-*
2731 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2732 PowerPC Solaris powerpcle-*-solaris*
2733 PowerPC Windows NT powerpcle-*-cygwin32
2734 PowerPC Netware powerpc-*-netware*
2735 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2736 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2737 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2738 Apple Macintosh (MPW) host N/A
2740 stuff.c (Program to stuff files into a specially prepared space in kdb)
2741 kdb-start.c (Main loop for the standalone kernel debugger)
2743 Configurations that have been declared obsolete in this release have
2744 been commented out. Unless there is activity to revive these
2745 configurations, the next release of GDB will have their sources
2746 permanently REMOVED.
2748 * REMOVED configurations and files
2750 Altos 3068 m68*-altos-*
2751 Convex c1-*-*, c2-*-*
2753 ARM RISCix arm-*-* (as host)
2757 * GDB has been converted to ISO C.
2759 GDB's source code has been converted to ISO C. In particular, the
2760 sources are fully protoized, and rely on standard headers being
2765 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2767 * The MI enabled by default.
2769 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2770 revised and enabled by default. Packages which use GDB as a debugging
2771 engine behind a UI or another front end are encouraged to switch to
2772 using the GDB/MI interface, instead of the old annotations interface
2773 which is now deprecated.
2775 * Support for debugging Pascal programs.
2777 GDB now includes support for debugging Pascal programs. The following
2778 main features are supported:
2780 - Pascal-specific data types such as sets;
2782 - automatic recognition of Pascal sources based on file-name
2785 - Pascal-style display of data types, variables, and functions;
2787 - a Pascal expression parser.
2789 However, some important features are not yet supported.
2791 - Pascal string operations are not supported at all;
2793 - there are some problems with boolean types;
2795 - Pascal type hexadecimal constants are not supported
2796 because they conflict with the internal variables format;
2798 - support for Pascal objects and classes is not full yet;
2800 - unlike Pascal, GDB is case-sensitive for symbol names.
2802 * Changes in completion.
2804 Commands such as `shell', `run' and `set args', which pass arguments
2805 to inferior programs, now complete on file names, similar to what
2806 users expect at the shell prompt.
2808 Commands which accept locations, such as `disassemble', `print',
2809 `breakpoint', `until', etc. now complete on filenames as well as
2810 program symbols. Thus, if you type "break foob TAB", and the source
2811 files linked into the programs include `foobar.c', that file name will
2812 be one of the candidates for completion. However, file names are not
2813 considered for completion after you typed a colon that delimits a file
2814 name from a name of a function in that file, as in "break foo.c:bar".
2816 `set demangle-style' completes on available demangling styles.
2818 * New platform-independent commands:
2820 It is now possible to define a post-hook for a command as well as a
2821 hook that runs before the command. For more details, see the
2822 documentation of `hookpost' in the GDB manual.
2824 * Changes in GNU/Linux native debugging.
2826 Support for debugging multi-threaded programs has been completely
2827 revised for all platforms except m68k and sparc. You can now debug as
2828 many threads as your system allows you to have.
2830 Attach/detach is supported for multi-threaded programs.
2832 Support for SSE registers was added for x86. This doesn't work for
2833 multi-threaded programs though.
2835 * Changes in MIPS configurations.
2837 Multi-arch support is enabled for all MIPS configurations.
2839 GDB can now be built as native debugger on SGI Irix 6.x systems for
2840 debugging n32 executables. (Debugging 64-bit executables is not yet
2843 * Unified support for hardware watchpoints in all x86 configurations.
2845 Most (if not all) native x86 configurations support hardware-assisted
2846 breakpoints and watchpoints in a unified manner. This support
2847 implements debug register sharing between watchpoints, which allows to
2848 put a virtually infinite number of watchpoints on the same address,
2849 and also supports watching regions up to 16 bytes with several debug
2852 The new maintenance command `maintenance show-debug-regs' toggles
2853 debugging print-outs in functions that insert, remove, and test
2854 watchpoints and hardware breakpoints.
2856 * Changes in the DJGPP native configuration.
2858 New command ``info dos sysinfo'' displays assorted information about
2859 the CPU, OS, memory, and DPMI server.
2861 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2862 display information about segment descriptors stored in GDT, LDT, and
2865 New commands ``info dos pde'' and ``info dos pte'' display entries
2866 from Page Directory and Page Tables (for now works with CWSDPMI only).
2867 New command ``info dos address-pte'' displays the Page Table entry for
2868 a given linear address.
2870 GDB can now pass command lines longer than 126 characters to the
2871 program being debugged (requires an update to the libdbg.a library
2872 which is part of the DJGPP development kit).
2874 DWARF2 debug info is now supported.
2876 It is now possible to `step' and `next' through calls to `longjmp'.
2878 * Changes in documentation.
2880 All GDB documentation was converted to GFDL, the GNU Free
2881 Documentation License.
2883 Tracepoints-related commands are now fully documented in the GDB
2886 TUI, the Text-mode User Interface, is now documented in the manual.
2888 Tracepoints-related commands are now fully documented in the GDB
2891 The "GDB Internals" manual now has an index. It also includes
2892 documentation of `ui_out' functions, GDB coding standards, x86
2893 hardware watchpoints, and memory region attributes.
2895 * GDB's version number moved to ``version.in''
2897 The Makefile variable VERSION has been replaced by the file
2898 ``version.in''. People creating GDB distributions should update the
2899 contents of this file.
2903 GUD support is now a standard part of the EMACS distribution.
2905 *** Changes in GDB 5.0:
2907 * Improved support for debugging FP programs on x86 targets
2909 Unified and much-improved support for debugging floating-point
2910 programs on all x86 targets. In particular, ``info float'' now
2911 displays the FP registers in the same format on all x86 targets, with
2912 greater level of detail.
2914 * Improvements and bugfixes in hardware-assisted watchpoints
2916 It is now possible to watch array elements, struct members, and
2917 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2918 on x86 targets no longer erroneously trigger when the address is
2921 * Improvements in the native DJGPP version of GDB
2923 The distribution now includes all the scripts and auxiliary files
2924 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2925 machines ``out of the box''.
2927 The DJGPP version can now debug programs that use signals. It is
2928 possible to catch signals that happened in the debuggee, deliver
2929 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2930 would kill the program being debugged.) Programs that hook hardware
2931 interrupts (keyboard, timer, etc.) can also be debugged.
2933 It is now possible to debug DJGPP programs that redirect their
2934 standard handles or switch them to raw (as opposed to cooked) mode, or
2935 even close them. The command ``run < foo > bar'' works as expected,
2936 and ``info terminal'' reports useful information about the debuggee's
2937 terminal, including raw/cooked mode, redirection, etc.
2939 The DJGPP version now uses termios functions for console I/O, which
2940 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2943 DOS-style file names with drive letters are now fully supported by
2946 It is now possible to debug DJGPP programs that switch their working
2947 directory. It is also possible to rerun the debuggee any number of
2948 times without restarting GDB; thus, you can use the same setup,
2949 breakpoints, etc. for many debugging sessions.
2951 * New native configurations
2953 ARM GNU/Linux arm*-*-linux*
2954 PowerPC GNU/Linux powerpc-*-linux*
2958 Motorola MCore mcore-*-*
2959 x86 VxWorks i[3456]86-*-vxworks*
2960 PowerPC VxWorks powerpc-*-vxworks*
2961 TI TMS320C80 tic80-*-*
2963 * OBSOLETE configurations
2965 Altos 3068 m68*-altos-*
2966 Convex c1-*-*, c2-*-*
2968 ARM RISCix arm-*-* (as host)
2971 Configurations that have been declared obsolete will be commented out,
2972 but the code will be left in place. If there is no activity to revive
2973 these configurations before the next release of GDB, the sources will
2974 be permanently REMOVED.
2976 * Gould support removed
2978 Support for the Gould PowerNode and NP1 has been removed.
2980 * New features for SVR4
2982 On SVR4 native platforms (such as Solaris), if you attach to a process
2983 without first loading a symbol file, GDB will now attempt to locate and
2984 load symbols from the running process's executable file.
2986 * Many C++ enhancements
2988 C++ support has been greatly improved. Overload resolution now works properly
2989 in almost all cases. RTTI support is on the way.
2991 * Remote targets can connect to a sub-program
2993 A popen(3) style serial-device has been added. This device starts a
2994 sub-process (such as a stand-alone simulator) and then communicates
2995 with that. The sub-program to run is specified using the syntax
2996 ``|<program> <args>'' vis:
2998 (gdb) set remotedebug 1
2999 (gdb) target extended-remote |mn10300-elf-sim program-args
3001 * MIPS 64 remote protocol
3003 A long standing bug in the mips64 remote protocol where by GDB
3004 expected certain 32 bit registers (ex SR) to be transfered as 32
3005 instead of 64 bits has been fixed.
3007 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3008 added to provide backward compatibility with older versions of GDB.
3010 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3012 The command ``set remotebinarydownload'' command has been replaced by
3013 ``set remote X-packet''. Other commands in ``set remote'' family
3014 include ``set remote P-packet''.
3016 * Breakpoint commands accept ranges.
3018 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3019 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3020 ``tracepoint passcount'' also accepts a range of tracepoints.
3022 * ``apropos'' command added.
3024 The ``apropos'' command searches through command names and
3025 documentation strings, printing out matches, making it much easier to
3026 try to find a command that does what you are looking for.
3030 A new machine oriented interface (MI) has been added to GDB. This
3031 interface is designed for debug environments running GDB as a separate
3032 process. This is part of the long term libGDB project. See the
3033 "GDB/MI" chapter of the GDB manual for further information. It can be
3034 enabled by configuring with:
3036 .../configure --enable-gdbmi
3038 *** Changes in GDB-4.18:
3040 * New native configurations
3042 HP-UX 10.20 hppa*-*-hpux10.20
3043 HP-UX 11.x hppa*-*-hpux11.0*
3044 M68K GNU/Linux m68*-*-linux*
3048 Fujitsu FR30 fr30-*-elf*
3049 Intel StrongARM strongarm-*-*
3050 Mitsubishi D30V d30v-*-*
3052 * OBSOLETE configurations
3054 Gould PowerNode, NP1 np1-*-*, pn-*-*
3056 Configurations that have been declared obsolete will be commented out,
3057 but the code will be left in place. If there is no activity to revive
3058 these configurations before the next release of GDB, the sources will
3059 be permanently REMOVED.
3063 As a compatibility experiment, GDB's source files buildsym.h and
3064 buildsym.c have been converted to pure standard C, no longer
3065 containing any K&R compatibility code. We believe that all systems in
3066 use today either come with a standard C compiler, or have a GCC port
3067 available. If this is not true, please report the affected
3068 configuration to bug-gdb@gnu.org immediately. See the README file for
3069 information about getting a standard C compiler if you don't have one
3074 GDB now uses readline 2.2.
3076 * set extension-language
3078 You can now control the mapping between filename extensions and source
3079 languages by using the `set extension-language' command. For instance,
3080 you can ask GDB to treat .c files as C++ by saying
3081 set extension-language .c c++
3082 The command `info extensions' lists all of the recognized extensions
3083 and their associated languages.
3085 * Setting processor type for PowerPC and RS/6000
3087 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3088 you can use the `set processor' command to specify what variant of the
3089 PowerPC family you are debugging. The command
3093 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3094 following PowerPC and RS6000 variants:
3096 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3097 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3099 403GC IBM PowerPC 403GC
3100 505 Motorola PowerPC 505
3101 860 Motorola PowerPC 860 or 850
3102 601 Motorola PowerPC 601
3103 602 Motorola PowerPC 602
3104 603 Motorola/IBM PowerPC 603 or 603e
3105 604 Motorola PowerPC 604 or 604e
3106 750 Motorola/IBM PowerPC 750 or 750
3108 At the moment, this command just tells GDB what to name the
3109 special-purpose processor registers. Since almost all the affected
3110 registers are inaccessible to user-level programs, this command is
3111 only useful for remote debugging in its present form.
3115 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3116 more extensive support for HP-UX. Added features include shared
3117 library support, kernel threads and hardware watchpoints for 11.00,
3118 support for HP's ANSI C and C++ compilers, and a compatibility mode
3119 for xdb and dbx commands.
3123 HP's donation includes the new concept of catchpoints, which is a
3124 generalization of the old catch command. On HP-UX, it is now possible
3125 to catch exec, fork, and vfork, as well as library loading.
3127 This means that the existing catch command has changed; its first
3128 argument now specifies the type of catch to be set up. See the
3129 output of "help catch" for a list of catchpoint types.
3131 * Debugging across forks
3133 On HP-UX, you can choose which process to debug when a fork() happens
3138 HP has donated a curses-based terminal user interface (TUI). To get
3139 it, build with --enable-tui. Although this can be enabled for any
3140 configuration, at present it only works for native HP debugging.
3142 * GDB remote protocol additions
3144 A new protocol packet 'X' that writes binary data is now available.
3145 Default behavior is to try 'X', then drop back to 'M' if the stub
3146 fails to respond. The settable variable `remotebinarydownload'
3147 allows explicit control over the use of 'X'.
3149 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3150 full 64-bit address. The command
3152 set remoteaddresssize 32
3154 can be used to revert to the old behaviour. For existing remote stubs
3155 the change should not be noticed, as the additional address information
3158 In order to assist in debugging stubs, you may use the maintenance
3159 command `packet' to send any text string to the stub. For instance,
3161 maint packet heythere
3163 sends the packet "$heythere#<checksum>". Note that it is very easy to
3164 disrupt a debugging session by sending the wrong packet at the wrong
3167 The compare-sections command allows you to compare section data on the
3168 target to what is in the executable file without uploading or
3169 downloading, by comparing CRC checksums.
3171 * Tracing can collect general expressions
3173 You may now collect general expressions at tracepoints. This requires
3174 further additions to the target-side stub; see tracepoint.c and
3175 doc/agentexpr.texi for further details.
3177 * mask-address variable for Mips
3179 For Mips targets, you may control the zeroing of the upper 32 bits of
3180 a 64-bit address by entering `set mask-address on'. This is mainly
3181 of interest to users of embedded R4xxx and R5xxx processors.
3183 * Higher serial baud rates
3185 GDB's serial code now allows you to specify baud rates 57600, 115200,
3186 230400, and 460800 baud. (Note that your host system may not be able
3187 to achieve all of these rates.)
3191 The i960 configuration now includes an initial implementation of a
3192 builtin simulator, contributed by Jim Wilson.
3195 *** Changes in GDB-4.17:
3197 * New native configurations
3199 Alpha GNU/Linux alpha*-*-linux*
3200 Unixware 2.x i[3456]86-unixware2*
3201 Irix 6.x mips*-sgi-irix6*
3202 PowerPC GNU/Linux powerpc-*-linux*
3203 PowerPC Solaris powerpcle-*-solaris*
3204 Sparc GNU/Linux sparc-*-linux*
3205 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3209 Argonaut Risc Chip (ARC) arc-*-*
3210 Hitachi H8/300S h8300*-*-*
3211 Matsushita MN10200 w/simulator mn10200-*-*
3212 Matsushita MN10300 w/simulator mn10300-*-*
3213 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3214 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3215 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3216 Mitsubishi D10V w/simulator d10v-*-*
3217 Mitsubishi M32R/D w/simulator m32r-*-elf*
3218 Tsqware Sparclet sparclet-*-*
3219 NEC V850 w/simulator v850-*-*
3221 * New debugging protocols
3223 ARM with RDI protocol arm*-*-*
3224 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3225 DDB and LSI variants of PMON protocol mips*-*-*
3226 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3227 PowerPC with SDS protocol powerpc{,le}-*-eabi
3228 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3232 All configurations can now understand and use the DWARF 2 debugging
3233 format. The choice is automatic, if the symbol file contains DWARF 2
3238 GDB now includes basic Java language support. This support is
3239 only useful with Java compilers that produce native machine code.
3241 * solib-absolute-prefix and solib-search-path
3243 For SunOS and SVR4 shared libraries, you may now set the prefix for
3244 loading absolute shared library symbol files, and the search path for
3245 locating non-absolute shared library symbol files.
3247 * Live range splitting
3249 GDB can now effectively debug code for which GCC has performed live
3250 range splitting as part of its optimization. See gdb/doc/LRS for
3251 more details on the expected format of the stabs information.
3255 GDB's support for the GNU Hurd, including thread debugging, has been
3256 updated to work with current versions of the Hurd.
3260 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3261 instruction set. ARM GDB automatically detects when Thumb
3262 instructions are in use, and adjusts disassembly and backtracing
3267 GDB's MIPS target configurations now handle the MIP16 16-bit
3272 GDB now includes support for overlays; if an executable has been
3273 linked such that multiple sections are based at the same address, GDB
3274 will decide which section to use for symbolic info. You can choose to
3275 control the decision manually, using overlay commands, or implement
3276 additional target-side support and use "overlay load-target" to bring
3277 in the overlay mapping. Do "help overlay" for more detail.
3281 The command "info symbol <address>" displays information about
3282 the symbol at the specified address.
3286 The standard remote protocol now includes an extension that allows
3287 asynchronous collection and display of trace data. This requires
3288 extensive support in the target-side debugging stub. Tracing mode
3289 includes a new interaction mode in GDB and new commands: see the
3290 file tracepoint.c for more details.
3294 Configurations for embedded MIPS now include a simulator contributed
3295 by Cygnus Solutions. The simulator supports the instruction sets
3296 of most MIPS variants.
3300 Sparc configurations may now include the ERC32 simulator contributed
3301 by the European Space Agency. The simulator is not built into
3302 Sparc targets by default; configure with --enable-sim to include it.
3306 For target configurations that may include multiple variants of a
3307 basic architecture (such as MIPS and SH), you may now set the
3308 architecture explicitly. "set arch" sets, "info arch" lists
3309 the possible architectures.
3311 *** Changes in GDB-4.16:
3313 * New native configurations
3315 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3316 M68K NetBSD m68k-*-netbsd*
3317 PowerPC AIX 4.x powerpc-*-aix*
3318 PowerPC MacOS powerpc-*-macos*
3319 PowerPC Windows NT powerpcle-*-cygwin32
3320 RS/6000 AIX 4.x rs6000-*-aix4*
3324 ARM with RDP protocol arm-*-*
3325 I960 with MON960 i960-*-coff
3326 MIPS VxWorks mips*-*-vxworks*
3327 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3328 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3330 Matra Sparclet sparclet-*-*
3334 The powerpc-eabi configuration now includes the PSIM simulator,
3335 contributed by Andrew Cagney, with assistance from Mike Meissner.
3336 PSIM is a very elaborate model of the PowerPC, including not only
3337 basic instruction set execution, but also details of execution unit
3338 performance and I/O hardware. See sim/ppc/README for more details.
3342 GDB now works with Solaris 2.5.
3344 * Windows 95/NT native
3346 GDB will now work as a native debugger on Windows 95 and Windows NT.
3347 To build it from source, you must use the "gnu-win32" environment,
3348 which uses a DLL to emulate enough of Unix to run the GNU tools.
3349 Further information, binaries, and sources are available at
3350 ftp.cygnus.com, under pub/gnu-win32.
3352 * dont-repeat command
3354 If a user-defined command includes the command `dont-repeat', then the
3355 command will not be repeated if the user just types return. This is
3356 useful if the command is time-consuming to run, so that accidental
3357 extra keystrokes don't run the same command many times.
3359 * Send break instead of ^C
3361 The standard remote protocol now includes an option to send a break
3362 rather than a ^C to the target in order to interrupt it. By default,
3363 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3365 * Remote protocol timeout
3367 The standard remote protocol includes a new variable `remotetimeout'
3368 that allows you to set the number of seconds before GDB gives up trying
3369 to read from the target. The default value is 2.
3371 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3373 By default GDB will automatically keep track of objects as they are
3374 loaded and unloaded by the dynamic linker. By using the command `set
3375 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3376 when shared library events occur, thus allowing you to set breakpoints
3377 in shared libraries which are explicitly loaded by the inferior.
3379 Note this feature does not work on hpux8. On hpux9 you must link
3380 /usr/lib/end.o into your program. This feature should work
3381 automatically on hpux10.
3383 * Irix 5.x hardware watchpoint support
3385 Irix 5 configurations now support the use of hardware watchpoints.
3387 * Mips protocol "SYN garbage limit"
3389 When debugging a Mips target using the `target mips' protocol, you
3390 may set the number of characters that GDB will ignore by setting
3391 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3392 every character. The default value is 1050.
3394 * Recording and replaying remote debug sessions
3396 If you set `remotelogfile' to the name of a file, gdb will write to it
3397 a recording of a remote debug session. This recording may then be
3398 replayed back to gdb using "gdbreplay". See gdbserver/README for
3399 details. This is useful when you have a problem with GDB while doing
3400 remote debugging; you can make a recording of the session and send it
3401 to someone else, who can then recreate the problem.
3403 * Speedups for remote debugging
3405 GDB includes speedups for downloading and stepping MIPS systems using
3406 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3407 and more efficient S-record downloading.
3409 * Memory use reductions and statistics collection
3411 GDB now uses less memory and reports statistics about memory usage.
3412 Try the `maint print statistics' command, for example.
3414 *** Changes in GDB-4.15:
3416 * Psymtabs for XCOFF
3418 The symbol reader for AIX GDB now uses partial symbol tables. This
3419 can greatly improve startup time, especially for large executables.
3421 * Remote targets use caching
3423 Remote targets now use a data cache to speed up communication with the
3424 remote side. The data cache could lead to incorrect results because
3425 it doesn't know about volatile variables, thus making it impossible to
3426 debug targets which use memory mapped I/O devices. `set remotecache
3427 off' turns the the data cache off.
3429 * Remote targets may have threads
3431 The standard remote protocol now includes support for multiple threads
3432 in the target system, using new protocol commands 'H' and 'T'. See
3433 gdb/remote.c for details.
3437 If GDB is configured with `--enable-netrom', then it will include
3438 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3439 acts as though it is a bank of ROM on the target board, but you can
3440 write into it over the network. GDB's support consists only of
3441 support for fast loading into the emulated ROM; to debug, you must use
3442 another protocol, such as standard remote protocol. The usual
3443 sequence is something like
3445 target nrom <netrom-hostname>
3447 target remote <netrom-hostname>:1235
3451 GDB now includes support for the Apple Macintosh, as a host only. It
3452 may be run as either an MPW tool or as a standalone application, and
3453 it can debug through the serial port. All the usual GDB commands are
3454 available, but to the target command, you must supply "serial" as the
3455 device type instead of "/dev/ttyXX". See mpw-README in the main
3456 directory for more information on how to build. The MPW configuration
3457 scripts */mpw-config.in support only a few targets, and only the
3458 mips-idt-ecoff target has been tested.
3462 GDB configuration now uses autoconf. This is not user-visible,
3463 but does simplify configuration and building.
3467 GDB now supports hpux10.
3469 *** Changes in GDB-4.14:
3471 * New native configurations
3473 x86 FreeBSD i[345]86-*-freebsd
3474 x86 NetBSD i[345]86-*-netbsd
3475 NS32k NetBSD ns32k-*-netbsd
3476 Sparc NetBSD sparc-*-netbsd
3480 A29K VxWorks a29k-*-vxworks
3481 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3482 CPU32 EST-300 emulator m68*-*-est*
3483 PowerPC ELF powerpc-*-elf
3486 * Alpha OSF/1 support for procfs
3488 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3489 possible to attach to running processes. As the mounting of the /proc
3490 filesystem is optional on the Alpha, GDB automatically determines
3491 the availability of /proc during startup. This can lead to problems
3492 if /proc is unmounted after GDB has been started.
3494 * Arguments to user-defined commands
3496 User commands may accept up to 10 arguments separated by whitespace.
3497 Arguments are accessed within the user command via $arg0..$arg9. A
3500 print $arg0 + $arg1 + $arg2
3502 To execute the command use:
3505 Defines the command "adder" which prints the sum of its three arguments.
3506 Note the arguments are text substitutions, so they may reference variables,
3507 use complex expressions, or even perform inferior function calls.
3509 * New `if' and `while' commands
3511 This makes it possible to write more sophisticated user-defined
3512 commands. Both commands take a single argument, which is the
3513 expression to evaluate, and must be followed by the commands to
3514 execute, one per line, if the expression is nonzero, the list being
3515 terminated by the word `end'. The `if' command list may include an
3516 `else' word, which causes the following commands to be executed only
3517 if the expression is zero.
3519 * Fortran source language mode
3521 GDB now includes partial support for Fortran 77. It will recognize
3522 Fortran programs and can evaluate a subset of Fortran expressions, but
3523 variables and functions may not be handled correctly. GDB will work
3524 with G77, but does not yet know much about symbols emitted by other
3527 * Better HPUX support
3529 Most debugging facilities now work on dynamic executables for HPPAs
3530 running hpux9 or later. You can attach to running dynamically linked
3531 processes, but by default the dynamic libraries will be read-only, so
3532 for instance you won't be able to put breakpoints in them. To change
3533 that behavior do the following before running the program:
3539 This will cause the libraries to be mapped private and read-write.
3540 To revert to the normal behavior, do this:
3546 You cannot set breakpoints or examine data in the library until after
3547 the library is loaded if the function/data symbols do not have
3550 GDB can now also read debug symbols produced by the HP C compiler on
3551 HPPAs (sorry, no C++, Fortran or 68k support).
3553 * Target byte order now dynamically selectable
3555 You can choose which byte order to use with a target system, via the
3556 commands "set endian big" and "set endian little", and you can see the
3557 current setting by using "show endian". You can also give the command
3558 "set endian auto", in which case GDB will use the byte order
3559 associated with the executable. Currently, only embedded MIPS
3560 configurations support dynamic selection of target byte order.
3562 * New DOS host serial code
3564 This version uses DPMI interrupts to handle buffered I/O, so you
3565 no longer need to run asynctsr when debugging boards connected to
3568 *** Changes in GDB-4.13:
3570 * New "complete" command
3572 This lists all the possible completions for the rest of the line, if it
3573 were to be given as a command itself. This is intended for use by emacs.
3575 * Trailing space optional in prompt
3577 "set prompt" no longer adds a space for you after the prompt you set. This
3578 allows you to set a prompt which ends in a space or one that does not.
3580 * Breakpoint hit counts
3582 "info break" now displays a count of the number of times the breakpoint
3583 has been hit. This is especially useful in conjunction with "ignore"; you
3584 can ignore a large number of breakpoint hits, look at the breakpoint info
3585 to see how many times the breakpoint was hit, then run again, ignoring one
3586 less than that number, and this will get you quickly to the last hit of
3589 * Ability to stop printing at NULL character
3591 "set print null-stop" will cause GDB to stop printing the characters of
3592 an array when the first NULL is encountered. This is useful when large
3593 arrays actually contain only short strings.
3595 * Shared library breakpoints
3597 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3598 breakpoints in shared libraries before the executable is run.
3600 * Hardware watchpoints
3602 There is a new hardware breakpoint for the watch command for sparclite
3603 targets. See gdb/sparclite/hw_breakpoint.note.
3605 Hardware watchpoints are also now supported under GNU/Linux.
3609 Annotations have been added. These are for use with graphical interfaces,
3610 and are still experimental. Currently only gdba.el uses these.
3612 * Improved Irix 5 support
3614 GDB now works properly with Irix 5.2.
3616 * Improved HPPA support
3618 GDB now works properly with the latest GCC and GAS.
3620 * New native configurations
3622 Sequent PTX4 i[34]86-sequent-ptx4
3623 HPPA running OSF/1 hppa*-*-osf*
3624 Atari TT running SVR4 m68*-*-sysv4*
3625 RS/6000 LynxOS rs6000-*-lynxos*
3629 OS/9000 i[34]86-*-os9k
3630 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3633 * Hitachi SH7000 and E7000-PC ICE support
3635 There is now support for communicating with the Hitachi E7000-PC ICE.
3636 This is available automatically when GDB is configured for the SH.
3640 As usual, a variety of small fixes and improvements, both generic
3641 and configuration-specific. See the ChangeLog for more detail.
3643 *** Changes in GDB-4.12:
3645 * Irix 5 is now supported
3649 GDB-4.12 on the HPPA has a number of changes which make it unable
3650 to debug the output from the currently released versions of GCC and
3651 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3652 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3653 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3656 *** Changes in GDB-4.11:
3658 * User visible changes:
3662 The "set remotedebug" option is now consistent between the mips remote
3663 target, remote targets using the gdb-specific protocol, UDI (AMD's
3664 debug protocol for the 29k) and the 88k bug monitor. It is now an
3665 integer specifying a debug level (normally 0 or 1, but 2 means more
3666 debugging info for the mips target).
3668 * DEC Alpha native support
3670 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3671 debug info, but GDB works fairly well with the DEC compiler and should
3672 work with a future GCC release. See the README file for a few
3673 Alpha-specific notes.
3675 * Preliminary thread implementation
3677 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3679 * LynxOS native and target support for 386
3681 This release has been hosted on LynxOS 2.2, and also can be configured
3682 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3685 * Improvements in C++ mangling/demangling.
3687 This release has much better g++ debugging, specifically in name
3688 mangling/demangling, virtual function calls, print virtual table,
3689 call methods, ...etc.
3691 *** Changes in GDB-4.10:
3693 * User visible changes:
3695 Remote debugging using the GDB-specific (`target remote') protocol now
3696 supports the `load' command. This is only useful if you have some
3697 other way of getting the stub to the target system, and you can put it
3698 somewhere in memory where it won't get clobbered by the download.
3700 Filename completion now works.
3702 When run under emacs mode, the "info line" command now causes the
3703 arrow to point to the line specified. Also, "info line" prints
3704 addresses in symbolic form (as well as hex).
3706 All vxworks based targets now support a user settable option, called
3707 vxworks-timeout. This option represents the number of seconds gdb
3708 should wait for responses to rpc's. You might want to use this if
3709 your vxworks target is, perhaps, a slow software simulator or happens
3710 to be on the far side of a thin network line.
3714 This release contains support for using a DEC alpha as a GDB host for
3715 cross debugging. Native alpha debugging is not supported yet.
3718 *** Changes in GDB-4.9:
3722 This is the first GDB release which is accompanied by a matching testsuite.
3723 The testsuite requires installation of dejagnu, which should be available
3724 via ftp from most sites that carry GNU software.
3728 'Cfront' style demangling has had its name changed to 'ARM' style, to
3729 emphasize that it was written from the specifications in the C++ Annotated
3730 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3731 disclaimers, it still generated too much confusion with users attempting to
3732 use gdb with AT&T cfront.
3736 GDB now uses a standard remote interface to a simulator library.
3737 So far, the library contains simulators for the Zilog Z8001/2, the
3738 Hitachi H8/300, H8/500 and Super-H.
3740 * New targets supported
3742 H8/300 simulator h8300-hitachi-hms or h8300hms
3743 H8/500 simulator h8500-hitachi-hms or h8500hms
3744 SH simulator sh-hitachi-hms or sh
3745 Z8000 simulator z8k-zilog-none or z8ksim
3746 IDT MIPS board over serial line mips-idt-ecoff
3748 Cross-debugging to GO32 targets is supported. It requires a custom
3749 version of the i386-stub.c module which is integrated with the
3750 GO32 memory extender.
3752 * New remote protocols
3754 MIPS remote debugging protocol.
3756 * New source languages supported
3758 This version includes preliminary support for Chill, a Pascal like language
3759 used by telecommunications companies. Chill support is also being integrated
3760 into the GNU compiler, but we don't know when it will be publically available.
3763 *** Changes in GDB-4.8:
3765 * HP Precision Architecture supported
3767 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3768 version of this support was available as a set of patches from the
3769 University of Utah. GDB does not support debugging of programs
3770 compiled with the HP compiler, because HP will not document their file
3771 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3772 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3774 Many problems in the preliminary version have been fixed.
3776 * Faster and better demangling
3778 We have improved template demangling and fixed numerous bugs in the GNU style
3779 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3780 character types (wchar_t) are now supported. Demangling of each symbol is now
3781 only done once, and is cached when the symbol table for a file is read in.
3782 This results in a small increase in memory usage for C programs, a moderate
3783 increase in memory usage for C++ programs, and a fantastic speedup in
3786 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3787 from the specifications in the Annotated Reference Manual, which AT&T's
3788 compiler does not actually implement.
3790 * G++ multiple inheritance compiler problem
3792 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3793 inheritance lattices was reworked to properly discover ambiguities. We
3794 recently found an example which causes this new algorithm to fail in a
3795 very subtle way, producing bad debug information for those classes.
3796 The file 'gcc.patch' (in this directory) can be applied to gcc to
3797 circumvent the problem. A future GCC release will contain a complete
3800 The previous G++ debug info problem (mentioned below for the gdb-4.7
3801 release) is fixed in gcc version 2.3.2.
3803 * Improved configure script
3805 The `configure' script will now attempt to guess your system type if
3806 you don't supply a host system type. The old scheme of supplying a
3807 host system triplet is preferable over using this. All the magic is
3808 done in the new `config.guess' script. Examine it for details.
3810 We have also brought our configure script much more in line with the FSF's
3811 version. It now supports the --with-xxx options. In particular,
3812 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3813 The resulting GDB will not be able to read arbitrary object file formats --
3814 only the format ``expected'' to be used on the configured target system.
3815 We hope to make this the default in a future release.
3817 * Documentation improvements
3819 There's new internal documentation on how to modify GDB, and how to
3820 produce clean changes to the code. We implore people to read it
3821 before submitting changes.
3823 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3824 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3825 `info' files are also provided. To build `info' files from scratch,
3826 you will need the latest `makeinfo' release, which will be available in
3827 a future texinfo-X.Y release.
3829 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3830 We're not sure exactly which versions have this problem, but it has
3831 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3832 or better. If that isn't possible, there is a patch in
3833 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3834 around this problem.
3838 GDB now supports array constants that can be used in expressions typed in by
3839 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3840 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3843 The new directory `gdb/sparclite' contains a program that demonstrates
3844 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3846 * New native hosts supported
3848 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3849 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3851 * New targets supported
3853 AMD 29k family via UDI a29k-amd-udi or udi29k
3855 * New file formats supported
3857 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3858 HPUX core files, and SCO 3.2v2 core files.
3862 Attaching to processes now works again; thanks for the many bug reports.
3864 We have also stomped on a bunch of core dumps caused by
3865 printf_filtered("%s") problems.
3867 We eliminated a copyright problem on the rpc and ptrace header files
3868 for VxWorks, which was discovered at the last minute during the 4.7
3869 release. You should now be able to build a VxWorks GDB.
3871 You can now interrupt gdb while an attached process is running. This
3872 will cause the attached process to stop, and give control back to GDB.
3874 We fixed problems caused by using too many file descriptors
3875 for reading symbols from object files and libraries. This was
3876 especially a problem for programs that used many (~100) shared
3879 The `step' command now only enters a subroutine if there is line number
3880 information for the subroutine. Otherwise it acts like the `next'
3881 command. Previously, `step' would enter subroutines if there was
3882 any debugging information about the routine. This avoids problems
3883 when using `cc -g1' on MIPS machines.
3885 * Internal improvements
3887 GDB's internal interfaces have been improved to make it easier to support
3888 debugging of multiple languages in the future.
3890 GDB now uses a common structure for symbol information internally.
3891 Minimal symbols (derived from linkage symbols in object files), partial
3892 symbols (from a quick scan of debug information), and full symbols
3893 contain a common subset of information, making it easier to write
3894 shared code that handles any of them.
3896 * New command line options
3898 We now accept --silent as an alias for --quiet.
3902 The memory-mapped-malloc library is now licensed under the GNU Library
3903 General Public License.
3905 *** Changes in GDB-4.7:
3907 * Host/native/target split
3909 GDB has had some major internal surgery to untangle the support for
3910 hosts and remote targets. Now, when you configure GDB for a remote
3911 target, it will no longer load in all of the support for debugging
3912 local programs on the host. When fully completed and tested, this will
3913 ensure that arbitrary host/target combinations are possible.
3915 The primary conceptual shift is to separate the non-portable code in
3916 GDB into three categories. Host specific code is required any time GDB
3917 is compiled on that host, regardless of the target. Target specific
3918 code relates to the peculiarities of the target, but can be compiled on
3919 any host. Native specific code is everything else: it can only be
3920 built when the host and target are the same system. Child process
3921 handling and core file support are two common `native' examples.
3923 GDB's use of /proc for controlling Unix child processes is now cleaner.
3924 It has been split out into a single module under the `target_ops' vector,
3925 plus two native-dependent functions for each system that uses /proc.
3927 * New hosts supported
3929 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3930 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3931 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3933 * New targets supported
3935 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3936 68030 and CPU32 m68030-*-*, m68332-*-*
3938 * New native hosts supported
3940 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3941 (386bsd is not well tested yet)
3942 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3944 * New file formats supported
3946 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3947 supports reading of `a.out.adobe' object files, which are an a.out
3948 format extended with minimal information about multiple sections.
3952 `show copying' is the same as the old `info copying'.
3953 `show warranty' is the same as `info warrantee'.
3954 These were renamed for consistency. The old commands continue to work.
3956 `info handle' is a new alias for `info signals'.
3958 You can now define pre-command hooks, which attach arbitrary command
3959 scripts to any command. The commands in the hook will be executed
3960 prior to the user's command. You can also create a hook which will be
3961 executed whenever the program stops. See gdb.texinfo.
3965 We now deal with Cfront style name mangling, and can even extract type
3966 info from mangled symbols. GDB can automatically figure out which
3967 symbol mangling style your C++ compiler uses.
3969 Calling of methods and virtual functions has been improved as well.
3973 The crash that occured when debugging Sun Ansi-C compiled binaries is
3974 fixed. This was due to mishandling of the extra N_SO stabs output
3977 We also finally got Ultrix 4.2 running in house, and fixed core file
3978 support, with help from a dozen people on the net.
3980 John M. Farrell discovered that the reason that single-stepping was so
3981 slow on all of the Mips based platforms (primarily SGI and DEC) was
3982 that we were trying to demangle and lookup a symbol used for internal
3983 purposes on every instruction that was being stepped through. Changing
3984 the name of that symbol so that it couldn't be mistaken for a C++
3985 mangled symbol sped things up a great deal.
3987 Rich Pixley sped up symbol lookups in general by getting much smarter
3988 about when C++ symbol mangling is necessary. This should make symbol
3989 completion (TAB on the command line) much faster. It's not as fast as
3990 we'd like, but it's significantly faster than gdb-4.6.
3994 A new user controllable variable 'call_scratch_address' can
3995 specify the location of a scratch area to be used when GDB
3996 calls a function in the target. This is necessary because the
3997 usual method of putting the scratch area on the stack does not work
3998 in systems that have separate instruction and data spaces.
4000 We integrated changes to support the 29k UDI (Universal Debugger
4001 Interface), but discovered at the last minute that we didn't have all
4002 of the appropriate copyright paperwork. We are working with AMD to
4003 resolve this, and hope to have it available soon.
4007 We have sped up the remote serial line protocol, especially for targets
4008 with lots of registers. It now supports a new `expedited status' ('T')
4009 message which can be used in place of the existing 'S' status message.
4010 This allows the remote stub to send only the registers that GDB
4011 needs to make a quick decision about single-stepping or conditional
4012 breakpoints, eliminating the need to fetch the entire register set for
4013 each instruction being stepped through.
4015 The GDB remote serial protocol now implements a write-through cache for
4016 registers, only re-reading the registers if the target has run.
4018 There is also a new remote serial stub for SPARC processors. You can
4019 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4020 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4021 processor with a serial port.
4025 Configure.in files have become much easier to read and modify. A new
4026 `table driven' format makes it more obvious what configurations are
4027 supported, and what files each one uses.
4031 There is a new opcodes library which will eventually contain all of the
4032 disassembly routines and opcode tables. At present, it only contains
4033 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4034 disassembler (binutils/objdump) to share these routines.
4036 The libiberty library is now copylefted under the GNU Library General
4037 Public License. This allows more liberal use, and was done so libg++
4038 can use it. This makes no difference to GDB, since the Library License
4039 grants all the rights from the General Public License.
4043 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4044 reference to the stabs symbol info used by the debugger. It is (as far
4045 as we know) the only published document on this fascinating topic. We
4046 encourage you to read it, compare it to the stabs information on your
4047 system, and send improvements on the document in general (to
4048 bug-gdb@prep.ai.mit.edu).
4050 And, of course, many bugs have been fixed.
4053 *** Changes in GDB-4.6:
4055 * Better support for C++ function names
4057 GDB now accepts as input the "demangled form" of C++ overloaded function
4058 names and member function names, and can do command completion on such names
4059 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4060 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4061 Make use of command completion, it is your friend.
4063 GDB also now accepts a variety of C++ mangled symbol formats. They are
4064 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4065 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4066 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4067 for the list of formats.
4069 * G++ symbol mangling problem
4071 Recent versions of gcc have a bug in how they emit debugging information for
4072 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4073 directory) can be applied to gcc to fix the problem. Alternatively, if you
4074 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4075 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4076 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4079 * New 'maintenance' command
4081 All of the commands related to hacking GDB internals have been moved out of
4082 the main command set, and now live behind the 'maintenance' command. This
4083 can also be abbreviated as 'mt'. The following changes were made:
4085 dump-me -> maintenance dump-me
4086 info all-breakpoints -> maintenance info breakpoints
4087 printmsyms -> maintenance print msyms
4088 printobjfiles -> maintenance print objfiles
4089 printpsyms -> maintenance print psymbols
4090 printsyms -> maintenance print symbols
4092 The following commands are new:
4094 maintenance demangle Call internal GDB demangler routine to
4095 demangle a C++ link name and prints the result.
4096 maintenance print type Print a type chain for a given symbol
4098 * Change to .gdbinit file processing
4100 We now read the $HOME/.gdbinit file before processing the argv arguments
4101 (e.g. reading symbol files or core files). This allows global parameters to
4102 be set, which will apply during the symbol reading. The ./.gdbinit is still
4103 read after argv processing.
4105 * New hosts supported
4107 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4109 GNU/Linux support i386-unknown-linux or linux
4111 We are also including code to support the HP/PA running BSD and HPUX. This
4112 is almost guaranteed not to work, as we didn't have time to test or build it
4113 for this release. We are including it so that the more adventurous (or
4114 masochistic) of you can play with it. We also had major problems with the
4115 fact that the compiler that we got from HP doesn't support the -g option.
4118 * New targets supported
4120 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4122 * More smarts about finding #include files
4124 GDB now remembers the compilation directory for all include files, and for
4125 all files from which C is generated (like yacc and lex sources). This
4126 greatly improves GDB's ability to find yacc/lex sources, and include files,
4127 especially if you are debugging your program from a directory different from
4128 the one that contains your sources.
4130 We also fixed a bug which caused difficulty with listing and setting
4131 breakpoints in include files which contain C code. (In the past, you had to
4132 try twice in order to list an include file that you hadn't looked at before.)
4134 * Interesting infernals change
4136 GDB now deals with arbitrary numbers of sections, where the symbols for each
4137 section must be relocated relative to that section's landing place in the
4138 target's address space. This work was needed to support ELF with embedded
4139 stabs used by Solaris-2.0.
4141 * Bug fixes (of course!)
4143 There have been loads of fixes for the following things:
4144 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4145 i960, stabs, DOS(GO32), procfs, etc...
4147 See the ChangeLog for details.
4149 *** Changes in GDB-4.5:
4151 * New machines supported (host and target)
4153 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4155 SGI Irix-4.x mips-sgi-irix4 or iris4
4157 * New malloc package
4159 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4160 Mmalloc is capable of handling mutiple heaps of memory. It is also
4161 capable of saving a heap to a file, and then mapping it back in later.
4162 This can be used to greatly speedup the startup of GDB by using a
4163 pre-parsed symbol table which lives in a mmalloc managed heap. For
4164 more details, please read mmalloc/mmalloc.texi.
4168 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4169 'help info proc' for details.
4171 * MIPS ecoff symbol table format
4173 The code that reads MIPS symbol table format is now supported on all hosts.
4174 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4177 * File name changes for MS-DOS
4179 Many files in the config directories have been renamed to make it easier to
4180 support GDB on MS-DOSe systems (which have very restrictive file name
4181 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4182 environment) is close to working but has some remaining problems. Note
4183 that debugging of DOS programs is not supported, due to limitations
4184 in the ``operating system'', but it can be used to host cross-debugging.
4186 * Cross byte order fixes
4188 Many fixes have been made to support cross debugging of Sparc and MIPS
4189 targets from hosts whose byte order differs.
4191 * New -mapped and -readnow options
4193 If memory-mapped files are available on your system through the 'mmap'
4194 system call, you can use the -mapped option on the `file' or
4195 `symbol-file' commands to cause GDB to write the symbols from your
4196 program into a reusable file. If the program you are debugging is
4197 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4198 Future GDB debugging sessions will notice the presence of this file,
4199 and will quickly map in symbol information from it, rather than reading
4200 the symbol table from the executable program. Using the '-mapped'
4201 option in a GDB `file' or `symbol-file' command has the same effect as
4202 starting GDB with the '-mapped' command-line option.
4204 You can cause GDB to read the entire symbol table immediately by using
4205 the '-readnow' option with any of the commands that load symbol table
4206 information (or on the GDB command line). This makes the command
4207 slower, but makes future operations faster.
4209 The -mapped and -readnow options are typically combined in order to
4210 build a `fred.syms' file that contains complete symbol information.
4211 A simple GDB invocation to do nothing but build a `.syms' file for future
4214 gdb -batch -nx -mapped -readnow programname
4216 The `.syms' file is specific to the host machine on which GDB is run.
4217 It holds an exact image of GDB's internal symbol table. It cannot be
4218 shared across multiple host platforms.
4220 * longjmp() handling
4222 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4223 siglongjmp() without losing control. This feature has not yet been ported to
4224 all systems. It currently works on many 386 platforms, all MIPS-based
4225 platforms (SGI, DECstation, etc), and Sun3/4.
4229 Preliminary work has been put in to support the new Solaris OS from Sun. At
4230 this time, it can control and debug processes, but it is not capable of
4235 As always, many many bug fixes. The major areas were with g++, and mipsread.
4236 People using the MIPS-based platforms should experience fewer mysterious
4237 crashes and trashed symbol tables.
4239 *** Changes in GDB-4.4:
4241 * New machines supported (host and target)
4243 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4245 BSD Reno on Vax vax-dec-bsd
4246 Ultrix on Vax vax-dec-ultrix
4248 * New machines supported (target)
4250 AMD 29000 embedded, using EBMON a29k-none-none
4254 GDB continues to improve its handling of C++. `References' work better.
4255 The demangler has also been improved, and now deals with symbols mangled as
4256 per the Annotated C++ Reference Guide.
4258 GDB also now handles `stabs' symbol information embedded in MIPS
4259 `ecoff' symbol tables. Since the ecoff format was not easily
4260 extensible to handle new languages such as C++, this appeared to be a
4261 good way to put C++ debugging info into MIPS binaries. This option
4262 will be supported in the GNU C compiler, version 2, when it is
4265 * New features for SVR4
4267 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4268 shared libraries. Debugging dynamically linked programs should present
4269 only minor differences from debugging statically linked programs.
4271 The `info proc' command will print out information about any process
4272 on an SVR4 system (including the one you are debugging). At the moment,
4273 it prints the address mappings of the process.
4275 If you bring up GDB on another SVR4 system, please send mail to
4276 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4278 * Better dynamic linking support in SunOS
4280 Reading symbols from shared libraries which contain debugging symbols
4281 now works properly. However, there remain issues such as automatic
4282 skipping of `transfer vector' code during function calls, which
4283 make it harder to debug code in a shared library, than to debug the
4284 same code linked statically.
4288 GDB is now using the latest `getopt' routines from the FSF. This
4289 version accepts the -- prefix for options with long names. GDB will
4290 continue to accept the old forms (-option and +option) as well.
4291 Various single letter abbreviations for options have been explicity
4292 added to the option table so that they won't get overshadowed in the
4293 future by other options that begin with the same letter.
4297 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4298 Many assorted bugs have been handled. Many more remain to be handled.
4299 See the various ChangeLog files (primarily in gdb and bfd) for details.
4302 *** Changes in GDB-4.3:
4304 * New machines supported (host and target)
4306 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4307 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4308 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4310 * Almost SCO Unix support
4312 We had hoped to support:
4313 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4314 (except for core file support), but we discovered very late in the release
4315 that it has problems with process groups that render gdb unusable. Sorry
4316 about that. I encourage people to fix it and post the fixes.
4318 * Preliminary ELF and DWARF support
4320 GDB can read ELF object files on System V Release 4, and can handle
4321 debugging records for C, in DWARF format, in ELF files. This support
4322 is preliminary. If you bring up GDB on another SVR4 system, please
4323 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4328 GDB now uses the latest `readline' library. One user-visible change
4329 is that two tabs will list possible command completions, which previously
4330 required typing M-? (meta-question mark, or ESC ?).
4334 The `stepi' bug that many of you noticed has been squashed.
4335 Many bugs in C++ have been handled. Many more remain to be handled.
4336 See the various ChangeLog files (primarily in gdb and bfd) for details.
4338 * State of the MIPS world (in case you wondered):
4340 GDB can understand the symbol tables emitted by the compilers
4341 supplied by most vendors of MIPS-based machines, including DEC. These
4342 symbol tables are in a format that essentially nobody else uses.
4344 Some versions of gcc come with an assembler post-processor called
4345 mips-tfile. This program is required if you want to do source-level
4346 debugging of gcc-compiled programs. I believe FSF does not ship
4347 mips-tfile with gcc version 1, but it will eventually come with gcc
4350 Debugging of g++ output remains a problem. g++ version 1.xx does not
4351 really support it at all. (If you're lucky, you should be able to get
4352 line numbers and stack traces to work, but no parameters or local
4353 variables.) With some work it should be possible to improve the
4356 When gcc version 2 is released, you will have somewhat better luck.
4357 However, even then you will get confusing results for inheritance and
4360 We will eventually provide full debugging of g++ output on
4361 DECstations. This will probably involve some kind of stabs-in-ecoff
4362 encapulation, but the details have not been worked out yet.
4365 *** Changes in GDB-4.2:
4367 * Improved configuration
4369 Only one copy of `configure' exists now, and it is not self-modifying.
4370 Porting BFD is simpler.
4374 The `step' and `next' commands now only stop at the first instruction
4375 of a source line. This prevents the multiple stops that used to occur
4376 in switch statements, for-loops, etc. `Step' continues to stop if a
4377 function that has debugging information is called within the line.
4381 Lots of small bugs fixed. More remain.
4383 * New host supported (not target)
4385 Intel 386 PC clone running Mach i386-none-mach
4388 *** Changes in GDB-4.1:
4390 * Multiple source language support
4392 GDB now has internal scaffolding to handle several source languages.
4393 It determines the type of each source file from its filename extension,
4394 and will switch expression parsing and number formatting to match the
4395 language of the function in the currently selected stack frame.
4396 You can also specifically set the language to be used, with
4397 `set language c' or `set language modula-2'.
4401 GDB now has preliminary support for the GNU Modula-2 compiler,
4402 currently under development at the State University of New York at
4403 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4404 continue through the fall of 1991 and into 1992.
4406 Other Modula-2 compilers are currently not supported, and attempting to
4407 debug programs compiled with them will likely result in an error as the
4408 symbol table is read. Feel free to work on it, though!
4410 There are hooks in GDB for strict type checking and range checking,
4411 in the `Modula-2 philosophy', but they do not currently work.
4415 GDB can now write to executable and core files (e.g. patch
4416 a variable's value). You must turn this switch on, specify
4417 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4418 by assigning a new value to a variable. Modifications take
4421 * Automatic SunOS shared library reading
4423 When you run your program, GDB automatically determines where its
4424 shared libraries (if any) have been loaded, and reads their symbols.
4425 The `share' command is no longer needed. This also works when
4426 examining core files.
4430 You can specify the number of lines that the `list' command shows.
4433 * New machines supported (host and target)
4435 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4436 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4437 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4439 * New hosts supported (not targets)
4441 IBM RT/PC: romp-ibm-aix or rtpc
4443 * New targets supported (not hosts)
4445 AMD 29000 embedded with COFF a29k-none-coff
4446 AMD 29000 embedded with a.out a29k-none-aout
4447 Ultracomputer remote kernel debug a29k-nyu-kern
4449 * New remote interfaces
4455 *** Changes in GDB-4.0:
4459 Wide output is wrapped at good places to make the output more readable.
4461 Gdb now supports cross-debugging from a host machine of one type to a
4462 target machine of another type. Communication with the target system
4463 is over serial lines. The ``target'' command handles connecting to the
4464 remote system; the ``load'' command will download a program into the
4465 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4466 also supports debugging of realtime processes running under VxWorks,
4467 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4468 stub on the target system.
4470 New CPUs supported include the AMD 29000 and Intel 960.
4472 GDB now reads object files and symbol tables via a ``binary file''
4473 library, which allows a single copy of GDB to debug programs of multiple
4474 object file types such as a.out and coff.
4476 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4477 refcard.dvi and refcard.ps are available to format it).
4480 * Control-Variable user interface simplified
4482 All variables that control the operation of the debugger can be set
4483 by the ``set'' command, and displayed by the ``show'' command.
4485 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4486 ``Show prompt'' produces the response:
4487 Gdb's prompt is new-gdb=>.
4489 What follows are the NEW set commands. The command ``help set'' will
4490 print a complete list of old and new set commands. ``help set FOO''
4491 will give a longer description of the variable FOO. ``show'' will show
4492 all of the variable descriptions and their current settings.
4494 confirm on/off: Enables warning questions for operations that are
4495 hard to recover from, e.g. rerunning the program while
4496 it is already running. Default is ON.
4498 editing on/off: Enables EMACS style command line editing
4499 of input. Previous lines can be recalled with
4500 control-P, the current line can be edited with control-B,
4501 you can search for commands with control-R, etc.
4504 history filename NAME: NAME is where the gdb command history
4505 will be stored. The default is .gdb_history,
4506 or the value of the environment variable
4509 history size N: The size, in commands, of the command history. The
4510 default is 256, or the value of the environment variable
4513 history save on/off: If this value is set to ON, the history file will
4514 be saved after exiting gdb. If set to OFF, the
4515 file will not be saved. The default is OFF.
4517 history expansion on/off: If this value is set to ON, then csh-like
4518 history expansion will be performed on
4519 command line input. The default is OFF.
4521 radix N: Sets the default radix for input and output. It can be set
4522 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4523 in the current radix, so "set radix 10" is always a no-op.
4525 height N: This integer value is the number of lines on a page. Default
4526 is 24, the current `stty rows'' setting, or the ``li#''
4527 setting from the termcap entry matching the environment
4530 width N: This integer value is the number of characters on a line.
4531 Default is 80, the current `stty cols'' setting, or the ``co#''
4532 setting from the termcap entry matching the environment
4535 Note: ``set screensize'' is obsolete. Use ``set height'' and
4536 ``set width'' instead.
4538 print address on/off: Print memory addresses in various command displays,
4539 such as stack traces and structure values. Gdb looks
4540 more ``symbolic'' if you turn this off; it looks more
4541 ``machine level'' with it on. Default is ON.
4543 print array on/off: Prettyprint arrays. New convenient format! Default
4546 print demangle on/off: Print C++ symbols in "source" form if on,
4549 print asm-demangle on/off: Same, for assembler level printouts
4552 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4555 * Support for Epoch Environment.
4557 The epoch environment is a version of Emacs v18 with windowing. One
4558 new command, ``inspect'', is identical to ``print'', except that if you
4559 are running in the epoch environment, the value is printed in its own
4563 * Support for Shared Libraries
4565 GDB can now debug programs and core files that use SunOS shared libraries.
4566 Symbols from a shared library cannot be referenced
4567 before the shared library has been linked with the program (this
4568 happens after you type ``run'' and before the function main() is entered).
4569 At any time after this linking (including when examining core files
4570 from dynamically linked programs), gdb reads the symbols from each
4571 shared library when you type the ``sharedlibrary'' command.
4572 It can be abbreviated ``share''.
4574 sharedlibrary REGEXP: Load shared object library symbols for files
4575 matching a unix regular expression. No argument
4576 indicates to load symbols for all shared libraries.
4578 info sharedlibrary: Status of loaded shared libraries.
4583 A watchpoint stops execution of a program whenever the value of an
4584 expression changes. Checking for this slows down execution
4585 tremendously whenever you are in the scope of the expression, but is
4586 quite useful for catching tough ``bit-spreader'' or pointer misuse
4587 problems. Some machines such as the 386 have hardware for doing this
4588 more quickly, and future versions of gdb will use this hardware.
4590 watch EXP: Set a watchpoint (breakpoint) for an expression.
4592 info watchpoints: Information about your watchpoints.
4594 delete N: Deletes watchpoint number N (same as breakpoints).
4595 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4596 enable N: Re-enables watchpoint number N (same as breakpoints).
4599 * C++ multiple inheritance
4601 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4604 * C++ exception handling
4606 Gdb now supports limited C++ exception handling. Besides the existing
4607 ability to breakpoint on an exception handler, gdb can breakpoint on
4608 the raising of an exception (before the stack is peeled back to the
4611 catch FOO: If there is a FOO exception handler in the dynamic scope,
4612 set a breakpoint to catch exceptions which may be raised there.
4613 Multiple exceptions (``catch foo bar baz'') may be caught.
4615 info catch: Lists all exceptions which may be caught in the
4616 current stack frame.
4619 * Minor command changes
4621 The command ``call func (arg, arg, ...)'' now acts like the print
4622 command, except it does not print or save a value if the function's result
4623 is void. This is similar to dbx usage.
4625 The ``up'' and ``down'' commands now always print the frame they end up
4626 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4627 frames without printing.
4629 * New directory command
4631 'dir' now adds directories to the FRONT of the source search path.
4632 The path starts off empty. Source files that contain debug information
4633 about the directory in which they were compiled can be found even
4634 with an empty path; Sun CC and GCC include this information. If GDB can't
4635 find your source file in the current directory, type "dir .".
4637 * Configuring GDB for compilation
4639 For normal use, type ``./configure host''. See README or gdb.texinfo
4642 GDB now handles cross debugging. If you are remotely debugging between
4643 two different machines, type ``./configure host -target=targ''.
4644 Host is the machine where GDB will run; targ is the machine
4645 where the program that you are debugging will run.