1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.1
6 * Windows Thread Information Block access.
8 On Windows targets, GDB now supports displaying the Windows Thread
9 Information Block (TIB) structure. This structure is visible either
10 by using the new command `info w32 thread-information-block' or, by
11 dereferencing the new convenience variable named `$_tlb', a
12 thread-specific pointer to the TIB. This feature is also supported
13 when remote debugging using GDBserver.
19 Return the address of the Windows Thread Information Block of a given thread.
21 * The source command now accepts a -s option to force searching for the
22 script in the source search path even if the script name specifies
25 * New features in the GDB remote stub, GDBserver
27 - GDBserver now support tracepoints. The feature is currently
28 supported by the i386-linux and amd64-linux builds.
30 * GDB now sends xmlRegisters= in qSupported packet to indicate that
31 it understands register description.
33 * The --batch flag now disables pagination and queries.
35 * X86 general purpose registers
37 GDB now supports reading/writing byte, word and double-word x86
38 general purpose registers directly. This means you can use, say,
39 $ah or $ax to refer, respectively, to the byte register AH and
40 16-bit word register AX that are actually portions of the 32-bit
41 register EAX or 64-bit register RAX.
43 * The `commands' command now accepts a range of breakpoints to modify.
44 A plain `commands' following a command that creates multiple
45 breakpoints affects all the breakpoints set by that command. This
46 applies to breakpoints set by `rbreak', and also applies when a
47 single `break' command creates multiple breakpoints (e.g.,
48 breakpoints on overloaded c++ functions).
50 * The `rbreak' command now accepts a filename specification as part of
51 its argument, limiting the functions selected by the regex to those
52 in the specified file.
54 * Support for remote debugging Windows and SymbianOS shared libraries
55 from Unix hosts has been improved. Non Windows GDB builds now can
56 understand target reported file names that follow MS-DOS based file
57 system semantics, such as file names that include drive letters and
58 use the backslash character as directory separator. This makes it
59 possible to transparently use the "set sysroot" and "set
60 solib-search-path" on Unix hosts to point as host copies of the
61 target's shared libraries. See the new command "set
62 target-file-system-kind" described below, and the "Commands to
63 specify files" section in the user manual for more information.
67 set target-file-system-kind unix|dos-based|auto
68 show target-file-system-kind
69 Set or show the assumed file system kind for target reported file
72 save breakpoints <filename>
73 Save all current breakpoint definitions to a file suitable for use
74 in a later debugging session. To read the saved breakpoint
75 definitions, use the `source' command.
77 `save tracepoints' is a new alias for `save-tracepoints'. The latter
82 ** The GDB Python API now has access to breakpoints, symbols, symbol
83 tables, program spaces, and frame's code blocks.
85 ** New functions gdb.target_charset, gdb.target_wide_charset,
86 gdb.progspaces, and gdb.current_progspace.
88 ** Pretty-printers are now also looked up in the current program space.
90 ** GDB now looks for names of Python scripts to auto-load in a
91 special section named `.debug_gdb_scripts', in addition to looking
92 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
94 * Tracepoint actions were unified with breakpoint commands. In particular,
95 there are no longer differences in "info break" output for breakpoints and
96 tracepoints and the "commands" command can be used for both tracepoints and
101 ARM Symbian arm*-*-symbianelf*
103 * D language support.
104 GDB now supports debugging programs written in the D programming
107 *** Changes in GDB 7.1
113 GDB now supports importing of namespaces in C++. This enables the
114 user to inspect variables from imported namespaces. Support for
115 namepace aliasing has also been added. So, if a namespace is
116 aliased in the current scope (e.g. namepace C=A; ) the user can
117 print variables using the alias (e.g. (gdb) print C::x).
121 All known bugs relating to the printing of virtual base class were
122 fixed. It is now possible to call overloaded static methods using a
127 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
128 and reinterpret_cast<> are now handled by the C++ expression parser.
132 Xilinx MicroBlaze microblaze-*-*
137 Xilinx MicroBlaze microblaze
140 * Multi-program debugging.
142 GDB now has support for multi-program (a.k.a. multi-executable or
143 multi-exec) debugging. This allows for debugging multiple inferiors
144 simultaneously each running a different program under the same GDB
145 session. See "Debugging Multiple Inferiors and Programs" in the
146 manual for more information. This implied some user visible changes
147 in the multi-inferior support. For example, "info inferiors" now
148 lists inferiors that are not running yet or that have exited
149 already. See also "New commands" and "New options" below.
151 * New tracing features
153 GDB's tracepoint facility now includes several new features:
155 ** Trace state variables
157 GDB tracepoints now include support for trace state variables, which
158 are variables managed by the target agent during a tracing
159 experiment. They are useful for tracepoints that trigger each
160 other, so for instance one tracepoint can count hits in a variable,
161 and then a second tracepoint has a condition that is true when the
162 count reaches a particular value. Trace state variables share the
163 $-syntax of GDB convenience variables, and can appear in both
164 tracepoint actions and condition expressions. Use the "tvariable"
165 command to create, and "info tvariables" to view; see "Trace State
166 Variables" in the manual for more detail.
170 GDB now includes an option for defining fast tracepoints, which
171 targets may implement more efficiently, such as by installing a jump
172 into the target agent rather than a trap instruction. The resulting
173 speedup can be by two orders of magnitude or more, although the
174 tradeoff is that some program locations on some target architectures
175 might not allow fast tracepoint installation, for instance if the
176 instruction to be replaced is shorter than the jump. To request a
177 fast tracepoint, use the "ftrace" command, with syntax identical to
178 the regular trace command.
180 ** Disconnected tracing
182 It is now possible to detach GDB from the target while it is running
183 a trace experiment, then reconnect later to see how the experiment
184 is going. In addition, a new variable disconnected-tracing lets you
185 tell the target agent whether to continue running a trace if the
186 connection is lost unexpectedly.
190 GDB now has the ability to save the trace buffer into a file, and
191 then use that file as a target, similarly to you can do with
192 corefiles. You can select trace frames, print data that was
193 collected in them, and use tstatus to display the state of the
194 tracing run at the moment that it was saved. To create a trace
195 file, use "tsave <filename>", and to use it, do "target tfile
198 ** Circular trace buffer
200 You can ask the target agent to handle the trace buffer as a
201 circular buffer, discarding the oldest trace frames to make room for
202 newer ones, by setting circular-trace-buffer to on. This feature may
203 not be available for all target agents.
208 The disassemble command, when invoked with two arguments, now requires
209 the arguments to be comma-separated.
212 The info variables command now displays variable definitions. Files
213 which only declare a variable are not shown.
216 The source command is now capable of sourcing Python scripts.
217 This feature is dependent on the debugger being build with Python
220 Related to this enhancement is also the introduction of a new command
221 "set script-extension" (see below).
223 * New commands (for set/show, see "New options" below)
225 record save [<FILENAME>]
226 Save a file (in core file format) containing the process record
227 execution log for replay debugging at a later time.
229 record restore <FILENAME>
230 Restore the process record execution log that was saved at an
231 earlier time, for replay debugging.
233 add-inferior [-copies <N>] [-exec <FILENAME>]
236 clone-inferior [-copies <N>] [ID]
237 Make a new inferior ready to execute the same program another
243 maint info program-spaces
244 List the program spaces loaded into GDB.
246 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
247 show remote interrupt-sequence
248 Allow the user to select one of ^C, a BREAK signal or BREAK-g
249 as the sequence to the remote target in order to interrupt the execution.
250 Ctrl-C is a default. Some system prefers BREAK which is high level of
251 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
252 Magic SysRq g. It is BREAK signal and character 'g'.
254 set remote interrupt-on-connect [on | off]
255 show remote interrupt-on-connect
256 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
257 remote target when gdb connects to it. This is needed when you debug
260 set remotebreak [on | off]
262 Deprecated. Use "set/show remote interrupt-sequence" instead.
264 tvariable $NAME [ = EXP ]
265 Create or modify a trace state variable.
268 List trace state variables and their values.
270 delete tvariable $NAME ...
271 Delete one or more trace state variables.
274 Evaluate the given expressions without collecting anything into the
275 trace buffer. (Valid in tracepoint actions only.)
277 ftrace FN / FILE:LINE / *ADDR
278 Define a fast tracepoint at the given function, line, or address.
280 * New expression syntax
282 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
283 GDB now parses 0b101010 identically with 42.
287 set follow-exec-mode new|same
288 show follow-exec-mode
289 Control whether GDB reuses the same inferior across an exec call or
290 creates a new one. This is useful to be able to restart the old
291 executable after the inferior having done an exec call.
293 set default-collect EXPR, ...
295 Define a list of expressions to be collected at each tracepoint.
296 This is a useful way to ensure essential items are not overlooked,
297 such as registers or a critical global variable.
299 set disconnected-tracing
300 show disconnected-tracing
301 If set to 1, the target is instructed to continue tracing if it
302 loses its connection to GDB. If 0, the target is to stop tracing
305 set circular-trace-buffer
306 show circular-trace-buffer
307 If set to on, the target is instructed to use a circular trace buffer
308 and discard the oldest trace frames instead of stopping the trace due
309 to a full trace buffer. If set to off, the trace stops when the buffer
310 fills up. Some targets may not support this.
312 set script-extension off|soft|strict
313 show script-extension
314 If set to "off", the debugger does not perform any script language
315 recognition, and all sourced files are assumed to be GDB scripts.
316 If set to "soft" (the default), files are sourced according to
317 filename extension, falling back to GDB scripts if the first
319 If set to "strict", files are sourced according to filename extension.
321 set ada trust-PAD-over-XVS on|off
322 show ada trust-PAD-over-XVS
323 If off, activate a workaround against a bug in the debugging information
324 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
325 the GCC sources for more information about the GNAT encoding and
326 PAD types in particular). It is always safe to set this option to
327 off, but this introduces a slight performance penalty. The default
330 * Python API Improvements
332 ** GDB provides the new class gdb.LazyString. This is useful in
333 some pretty-printing cases. The new method gdb.Value.lazy_string
334 provides a simple way to create objects of this type.
336 ** The fields returned by gdb.Type.fields now have an
337 `is_base_class' attribute.
339 ** The new method gdb.Type.range returns the range of an array type.
341 ** The new method gdb.parse_and_eval can be used to parse and
342 evaluate an expression.
347 Define a trace state variable.
350 Get the current value of a trace state variable.
353 Set desired tracing behavior upon disconnection.
356 Set the trace buffer to be linear or circular.
359 Get data about the tracepoints currently in use.
363 Process record now works correctly with hardware watchpoints.
365 Multiple bug fixes have been made to the mips-irix port, making it
366 much more reliable. In particular:
367 - Debugging threaded applications is now possible again. Previously,
368 GDB would hang while starting the program, or while waiting for
369 the program to stop at a breakpoint.
370 - Attaching to a running process no longer hangs.
371 - An error occurring while loading a core file has been fixed.
372 - Changing the value of the PC register now works again. This fixes
373 problems observed when using the "jump" command, or when calling
374 a function from GDB, or even when assigning a new value to $pc.
375 - With the "finish" and "return" commands, the return value for functions
376 returning a small array is now correctly printed.
377 - It is now possible to break on shared library code which gets executed
378 during a shared library init phase (code executed while executing
379 their .init section). Previously, the breakpoint would have no effect.
380 - GDB is now able to backtrace through the signal handler for
381 non-threaded programs.
383 PIE (Position Independent Executable) programs debugging is now supported.
384 This includes debugging execution of PIC (Position Independent Code) shared
385 libraries although for that, it should be possible to run such libraries as an
388 *** Changes in GDB 7.0
390 * GDB now has an interface for JIT compilation. Applications that
391 dynamically generate code can create symbol files in memory and register
392 them with GDB. For users, the feature should work transparently, and
393 for JIT developers, the interface is documented in the GDB manual in the
394 "JIT Compilation Interface" chapter.
396 * Tracepoints may now be conditional. The syntax is as for
397 breakpoints; either an "if" clause appended to the "trace" command,
398 or the "condition" command is available. GDB sends the condition to
399 the target for evaluation using the same bytecode format as is used
400 for tracepoint actions.
402 * "disassemble" command with a /r modifier, print the raw instructions
403 in hex as well as in symbolic form.
405 * Process record and replay
407 In a architecture environment that supports ``process record and
408 replay'', ``process record and replay'' target can record a log of
409 the process execution, and replay it with both forward and reverse
412 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
413 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
414 set execution-direction {forward|reverse}, for targets that support
417 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
418 feature is available with a native GDB running on kernel version
421 * GDB now has support for multi-byte and wide character sets on the
422 target. Strings whose character type is wchar_t, char16_t, or
423 char32_t are now correctly printed. GDB supports wide- and unicode-
424 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
425 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
426 `printf'. This feature requires iconv to work properly; if your
427 system does not have a working iconv, GDB can use GNU libiconv. See
428 the installation instructions for more information.
430 * GDB now supports automatic retrieval of shared library files from
431 remote targets. To use this feature, specify a system root that begins
432 with the `remote:' prefix, either via the `set sysroot' command or via
433 the `--with-sysroot' configure-time option.
435 * "info sharedlibrary" now takes an optional regex of libraries to show,
436 and it now reports if a shared library has no debugging information.
438 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
439 now complete on file names.
441 * When completing in expressions, gdb will attempt to limit
442 completions to allowable structure or union fields, where appropriate.
443 For instance, consider:
445 # struct example { int f1; double f2; };
446 # struct example variable;
449 If the user types TAB at the end of this command line, the available
450 completions will be "f1" and "f2".
452 * Inlined functions are now supported. They show up in backtraces, and
453 the "step", "next", and "finish" commands handle them automatically.
455 * GDB now supports the token-splicing (##) and stringification (#)
456 operators when expanding macros. It also supports variable-arity
459 * GDB now supports inspecting extra signal information, exported by
460 the new $_siginfo convenience variable. The feature is currently
461 implemented on linux ARM, i386 and amd64.
463 * GDB can now display the VFP floating point registers and NEON vector
464 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
465 can provide these registers (requires Linux 2.6.30 or later). Remote
466 and simulator targets may also provide them.
471 Search memory for a sequence of bytes.
474 Turn off `+'/`-' protocol acknowledgments to permit more efficient
475 operation over reliable transport links. Use of this packet is
476 controlled by the `set remote noack-packet' command.
479 Kill the process with the specified process ID. Use this in preference
480 to `k' when multiprocess protocol extensions are supported.
483 Obtains additional operating system information
487 Read or write additional signal information.
489 * Removed remote protocol undocumented extension
491 An undocumented extension to the remote protocol's `S' stop reply
492 packet that permited the stub to pass a process id was removed.
493 Remote servers should use the `T' stop reply packet instead.
495 * The "disassemble" command now supports an optional /m modifier to print mixed
498 * GDB now supports multiple function calling conventions according to the
499 DWARF-2 DW_AT_calling_convention function attribute.
501 * The SH target utilizes the aforementioned change to distinguish between gcc
502 and Renesas calling convention. It also adds the new CLI commands
503 `set/show sh calling-convention'.
505 * GDB can now read compressed debug sections, as produced by GNU gold
506 with the --compress-debug-sections=zlib flag.
508 * 64-bit core files are now supported on AIX.
510 * Thread switching is now supported on Tru64.
512 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
513 which will be allocated using malloc later in program execution.
515 * The qXfer:libraries:read remote procotol packet now allows passing a
516 list of section offsets.
518 * On GNU/Linux, GDB can now attach to stopped processes. Several race
519 conditions handling signals delivered during attach or thread creation
520 have also been fixed.
522 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
523 From the user's standpoint, all unqualified instances of True and False
524 are treated as the standard definitions, regardless of context.
526 * GDB now parses C++ symbol and type names more flexibly. For
529 template<typename T> class C { };
532 GDB will now correctly handle all of:
534 ptype C<char const *>
536 ptype C<const char *>
539 * New features in the GDB remote stub, gdbserver
541 - The "--wrapper" command-line argument tells gdbserver to use a
542 wrapper program to launch programs for debugging.
544 - On PowerPC and S/390 targets, it is now possible to use a single
545 gdbserver executable to debug both 32-bit and 64-bit programs.
546 (This requires gdbserver itself to be built as a 64-bit executable.)
548 - gdbserver uses the new noack protocol mode for TCP connections to
549 reduce communications latency, if also supported and enabled in GDB.
551 - Support for the sparc64-linux-gnu target is now included in
554 - The amd64-linux build of gdbserver now supports debugging both
555 32-bit and 64-bit programs.
557 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
558 now support hardware watchpoints, and will use them automatically
563 GDB now has support for scripting using Python. Whether this is
564 available is determined at configure time.
566 New GDB commands can now be written in Python.
568 * Ada tasking support
570 Ada tasks can now be inspected in GDB. The following commands have
574 Print the list of Ada tasks.
576 Print detailed information about task number N.
578 Print the task number of the current task.
580 Switch the context of debugging to task number N.
582 * Support for user-defined prefixed commands. The "define" command can
583 add new commands to existing prefixes, e.g. "target".
585 * Multi-inferior, multi-process debugging.
587 GDB now has generalized support for multi-inferior debugging. See
588 "Debugging Multiple Inferiors" in the manual for more information.
589 Although availability still depends on target support, the command
590 set is more uniform now. The GNU/Linux specific multi-forks support
591 has been migrated to this new framework. This implied some user
592 visible changes; see "New commands" and also "Removed commands"
595 * Target descriptions can now describe the target OS ABI. See the
596 "Target Description Format" section in the user manual for more
599 * Target descriptions can now describe "compatible" architectures
600 to indicate that the target can execute applications for a different
601 architecture in addition to those for the main target architecture.
602 See the "Target Description Format" section in the user manual for
605 * Multi-architecture debugging.
607 GDB now includes general supports for debugging applications on
608 hybrid systems that use more than one single processor architecture
609 at the same time. Each such hybrid architecture still requires
610 specific support to be added. The only hybrid architecture supported
611 in this version of GDB is the Cell Broadband Engine.
613 * GDB now supports integrated debugging of Cell/B.E. applications that
614 use both the PPU and SPU architectures. To enable support for hybrid
615 Cell/B.E. debugging, you need to configure GDB to support both the
616 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
617 --enable-targets configure option.
619 * Non-stop mode debugging.
621 For some targets, GDB now supports an optional mode of operation in
622 which you can examine stopped threads while other threads continue
623 to execute freely. This is referred to as non-stop mode, with the
624 old mode referred to as all-stop mode. See the "Non-Stop Mode"
625 section in the user manual for more information.
627 To be able to support remote non-stop debugging, a remote stub needs
628 to implement the non-stop mode remote protocol extensions, as
629 described in the "Remote Non-Stop" section of the user manual. The
630 GDB remote stub, gdbserver, has been adjusted to support these
631 extensions on linux targets.
633 * New commands (for set/show, see "New options" below)
635 catch syscall [NAME(S) | NUMBER(S)]
636 Catch system calls. Arguments, which should be names of system
637 calls or their numbers, mean catch only those syscalls. Without
638 arguments, every syscall will be caught. When the inferior issues
639 any of the specified syscalls, GDB will stop and announce the system
640 call, both when it is called and when its call returns. This
641 feature is currently available with a native GDB running on the
642 Linux Kernel, under the following architectures: x86, x86_64,
643 PowerPC and PowerPC64.
645 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
647 Search memory for a sequence of bytes.
649 maint set python print-stack
650 maint show python print-stack
651 Show a stack trace when an error is encountered in a Python script.
654 Invoke CODE by passing it to the Python interpreter.
659 These allow macros to be defined, undefined, and listed
663 Show operating system information about processes.
666 List the inferiors currently under GDB's control.
669 Switch focus to inferior number NUM.
672 Detach from inferior number NUM.
675 Kill inferior number NUM.
680 show spu stop-on-load
681 Control whether to stop for new SPE threads during Cell/B.E. debugging.
683 set spu auto-flush-cache
684 show spu auto-flush-cache
685 Control whether to automatically flush the software-managed cache
686 during Cell/B.E. debugging.
688 set sh calling-convention
689 show sh calling-convention
690 Control the calling convention used when calling SH target functions.
694 Control display of timestamps with GDB debugging output.
696 set disassemble-next-line
697 show disassemble-next-line
698 Control display of disassembled source lines or instructions when
701 set remote noack-packet
702 show remote noack-packet
703 Set/show the use of remote protocol QStartNoAckMode packet. See above
704 under "New remote packets."
706 set remote query-attached-packet
707 show remote query-attached-packet
708 Control use of remote protocol `qAttached' (query-attached) packet.
710 set remote read-siginfo-object
711 show remote read-siginfo-object
712 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
715 set remote write-siginfo-object
716 show remote write-siginfo-object
717 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
720 set remote reverse-continue
721 show remote reverse-continue
722 Control use of remote protocol 'bc' (reverse-continue) packet.
724 set remote reverse-step
725 show remote reverse-step
726 Control use of remote protocol 'bs' (reverse-step) packet.
728 set displaced-stepping
729 show displaced-stepping
730 Control displaced stepping mode. Displaced stepping is a way to
731 single-step over breakpoints without removing them from the debuggee.
732 Also known as "out-of-line single-stepping".
736 Control display of debugging info for displaced stepping.
738 maint set internal-error
739 maint show internal-error
740 Control what GDB does when an internal error is detected.
742 maint set internal-warning
743 maint show internal-warning
744 Control what GDB does when an internal warning is detected.
749 Use a wrapper program to launch programs for debugging.
751 set multiple-symbols (all|ask|cancel)
752 show multiple-symbols
753 The value of this variable can be changed to adjust the debugger behavior
754 when an expression or a breakpoint location contains an ambiguous symbol
755 name (an overloaded function name, for instance).
757 set breakpoint always-inserted
758 show breakpoint always-inserted
759 Keep breakpoints always inserted in the target, as opposed to inserting
760 them when resuming the target, and removing them when the target stops.
761 This option can improve debugger performance on slow remote targets.
763 set arm fallback-mode (arm|thumb|auto)
764 show arm fallback-mode
765 set arm force-mode (arm|thumb|auto)
767 These commands control how ARM GDB determines whether instructions
768 are ARM or Thumb. The default for both settings is auto, which uses
769 the current CPSR value for instructions without symbols; previous
770 versions of GDB behaved as if "set arm fallback-mode arm".
772 set disable-randomization
773 show disable-randomization
774 Standalone programs run with the virtual address space randomization enabled
775 by default on some platforms. This option keeps the addresses stable across
776 multiple debugging sessions.
780 Control whether other threads are stopped or not when some thread hits
785 Requests that asynchronous execution is enabled in the target, if available.
786 In this case, it's possible to resume target in the background, and interact
787 with GDB while the target is running. "show target-async" displays the
788 current state of asynchronous execution of the target.
790 set target-wide-charset
791 show target-wide-charset
792 The target-wide-charset is the name of the character set that GDB
793 uses when printing characters whose type is wchar_t.
795 set tcp auto-retry (on|off)
797 set tcp connect-timeout
798 show tcp connect-timeout
799 These commands allow GDB to retry failed TCP connections to a remote stub
800 with a specified timeout period; this is useful if the stub is launched
801 in parallel with GDB but may not be ready to accept connections immediately.
803 set libthread-db-search-path
804 show libthread-db-search-path
805 Control list of directories which GDB will search for appropriate
808 set schedule-multiple (on|off)
809 show schedule-multiple
810 Allow GDB to resume all threads of all processes or only threads of
815 Use more aggressive caching for accesses to the stack. This improves
816 performance of remote debugging (particularly backtraces) without
817 affecting correctness.
819 set interactive-mode (on|off|auto)
820 show interactive-mode
821 Control whether GDB runs in interactive mode (on) or not (off).
822 When in interactive mode, GDB waits for the user to answer all
823 queries. Otherwise, GDB does not wait and assumes the default
824 answer. When set to auto (the default), GDB determines which
825 mode to use based on the stdin settings.
830 For program forks, this is replaced by the new more generic `info
831 inferiors' command. To list checkpoints, you can still use the
832 `info checkpoints' command, which was an alias for the `info forks'
836 Replaced by the new `inferior' command. To switch between
837 checkpoints, you can still use the `restart' command, which was an
838 alias for the `fork' command.
841 This is removed, since some targets don't have a notion of
842 processes. To switch between processes, you can still use the
843 `inferior' command using GDB's own inferior number.
846 For program forks, this is replaced by the new more generic `kill
847 inferior' command. To delete a checkpoint, you can still use the
848 `delete checkpoint' command, which was an alias for the `delete
852 For program forks, this is replaced by the new more generic `detach
853 inferior' command. To detach a checkpoint, you can still use the
854 `detach checkpoint' command, which was an alias for the `detach
857 * New native configurations
859 x86/x86_64 Darwin i[34567]86-*-darwin*
861 x86_64 MinGW x86_64-*-mingw*
865 Lattice Mico32 lm32-*
866 x86 DICOS i[34567]86-*-dicos*
867 x86_64 DICOS x86_64-*-dicos*
870 * The GDB remote stub, gdbserver, now supports x86 Windows CE
871 (mingw32ce) debugging.
877 These commands were actually not implemented on any target.
879 *** Changes in GDB 6.8
881 * New native configurations
883 NetBSD/hppa hppa*-*netbsd*
884 Xtensa GNU/Linux xtensa*-*-linux*
888 NetBSD/hppa hppa*-*-netbsd*
889 Xtensa GNU/Lunux xtensa*-*-linux*
891 * Change in command line behavior -- corefiles vs. process ids.
893 When the '-p NUMBER' or '--pid NUMBER' options are used, and
894 attaching to process NUMBER fails, GDB no longer attempts to open a
895 core file named NUMBER. Attaching to a program using the -c option
896 is no longer supported. Instead, use the '-p' or '--pid' options.
898 * GDB can now be built as a native debugger for debugging Windows x86
899 (mingw32) Portable Executable (PE) programs.
901 * Pending breakpoints no longer change their number when their address
904 * GDB now supports breakpoints with multiple locations,
905 including breakpoints on C++ constructors, inside C++ templates,
906 and in inlined functions.
908 * GDB's ability to debug optimized code has been improved. GDB more
909 accurately identifies function bodies and lexical blocks that occupy
910 more than one contiguous range of addresses.
912 * Target descriptions can now describe registers for PowerPC.
914 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
915 registers on PowerPC targets.
917 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
918 targets even when the libthread_db library is not available.
920 * The GDB remote stub, gdbserver, now supports the new file transfer
921 commands (remote put, remote get, and remote delete).
923 * The GDB remote stub, gdbserver, now supports run and attach in
924 extended-remote mode.
926 * hppa*64*-*-hpux11* target broken
927 The debugger is unable to start a program and fails with the following
928 error: "Error trying to get information about dynamic linker".
929 The gdb-6.7 release is also affected.
931 * GDB now supports the --enable-targets= configure option to allow
932 building a single GDB executable that supports multiple remote
933 target architectures.
935 * GDB now supports debugging C and C++ programs which use the
936 Decimal Floating Point extension. In addition, the PowerPC target
937 now has a set of pseudo-registers to inspect decimal float values
938 stored in two consecutive float registers.
940 * The -break-insert MI command can optionally create pending
943 * Improved support for debugging Ada
944 Many improvements to the Ada language support have been made. These
946 - Better support for Ada2005 interface types
947 - Improved handling of arrays and slices in general
948 - Better support for Taft-amendment types
949 - The '{type} ADDRESS' expression is now allowed on the left hand-side
951 - Improved command completion in Ada
954 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
959 set print frame-arguments (all|scalars|none)
960 show print frame-arguments
961 The value of this variable can be changed to control which argument
962 values should be printed by the debugger when displaying a frame.
967 Transfer files to and from a remote target, and delete remote files.
974 Transfer files to and from a remote target, and delete remote files.
983 Open, close, read, write, and delete files on the remote system.
986 Attach to an existing process on the remote system, in extended-remote
990 Run a new process on the remote system, in extended-remote mode.
992 *** Changes in GDB 6.7
994 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
995 bfd, libiberty and opcodes, as revealed by static analysis donated by
996 Coverity, Inc. (http://scan.coverity.com).
998 * When looking up multiply-defined global symbols, GDB will now prefer the
999 symbol definition in the current shared library if it was built using the
1000 -Bsymbolic linker option.
1002 * When the Text User Interface (TUI) is not configured, GDB will now
1003 recognize the -tui command-line option and print a message that the TUI
1006 * The GDB remote stub, gdbserver, now has lower overhead for high
1007 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1009 * GDB for MIPS targets now autodetects whether a remote target provides
1010 32-bit or 64-bit register values.
1012 * Support for C++ member pointers has been improved.
1014 * GDB now understands XML target descriptions, which specify the
1015 target's overall architecture. GDB can read a description from
1016 a local file or over the remote serial protocol.
1018 * Vectors of single-byte data use a new integer type which is not
1019 automatically displayed as character or string data.
1021 * The /s format now works with the print command. It displays
1022 arrays of single-byte integers and pointers to single-byte integers
1025 * Target descriptions can now describe target-specific registers,
1026 for architectures which have implemented the support (currently
1027 only ARM, M68K, and MIPS).
1029 * GDB and the GDB remote stub, gdbserver, now support the XScale
1032 * The GDB remote stub, gdbserver, has been updated to support
1033 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1034 has been rewritten to use the standard GDB remote protocol.
1036 * GDB can now step into C++ functions which are called through thunks.
1038 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1040 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1041 layout. It also supports a TextSeg= and DataSeg= response when only
1042 segment base addresses (rather than offsets) are available.
1044 * The /i format now outputs any trailing branch delay slot instructions
1045 immediately following the last instruction within the count specified.
1047 * The GDB remote protocol "T" stop reply packet now supports a
1048 "library" response. Combined with the new "qXfer:libraries:read"
1049 packet, this response allows GDB to debug shared libraries on targets
1050 where the operating system manages the list of loaded libraries (e.g.
1051 Windows and SymbianOS).
1053 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1054 (DLLs) on Windows and Windows CE targets.
1056 * GDB now supports a faster verification that a .debug file matches its binary
1057 according to its build-id signature, if the signature is present.
1063 Enable or disable hardware flow control (RTS/CTS) on the serial port
1064 when debugging using remote targets.
1066 set mem inaccessible-by-default
1067 show mem inaccessible-by-default
1068 If the target supplies a memory map, for instance via the remote
1069 protocol's "qXfer:memory-map:read" packet, setting this variable
1070 prevents GDB from accessing memory outside the memory map. This
1071 is useful for targets with memory mapped registers or which react
1072 badly to accesses of unmapped address space.
1074 set breakpoint auto-hw
1075 show breakpoint auto-hw
1076 If the target supplies a memory map, for instance via the remote
1077 protocol's "qXfer:memory-map:read" packet, setting this variable
1078 lets GDB use hardware breakpoints automatically for memory regions
1079 where it can not use software breakpoints. This covers both the
1080 "break" command and internal breakpoints used for other commands
1081 including "next" and "finish".
1084 catch exception unhandled
1085 Stop the program execution when Ada exceptions are raised.
1088 Stop the program execution when an Ada assertion failed.
1092 Set an alternate system root for target files. This is a more
1093 general version of "set solib-absolute-prefix", which is now
1094 an alias to "set sysroot".
1097 Provide extended SPU facility status information. This set of
1098 commands is available only when debugging the Cell/B.E. SPU
1101 * New native configurations
1103 OpenBSD/sh sh*-*openbsd*
1106 unset tdesc filename
1108 Use the specified local file as an XML target description, and do
1109 not query the target for its built-in description.
1113 OpenBSD/sh sh*-*-openbsd*
1114 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1115 Toshiba Media Processor mep-elf
1117 * New remote packets
1120 Ignore the specified signals; pass them directly to the debugged program
1121 without stopping other threads or reporting them to GDB.
1123 qXfer:features:read:
1124 Read an XML target description from the target, which describes its
1129 Read or write contents of an spufs file on the target system. These
1130 packets are available only on the Cell/B.E. SPU architecture.
1132 qXfer:libraries:read:
1133 Report the loaded shared libraries. Combined with new "T" packet
1134 response, this packet allows GDB to debug shared libraries on
1135 targets where the operating system manages the list of loaded
1136 libraries (e.g. Windows and SymbianOS).
1140 Support for these obsolete configurations has been removed.
1148 i[34567]86-*-lynxos*
1149 i[34567]86-*-netware*
1150 i[34567]86-*-sco3.2v5*
1151 i[34567]86-*-sco3.2v4*
1153 i[34567]86-*-sysv4.2*
1156 i[34567]86-*-unixware2*
1157 i[34567]86-*-unixware*
1166 * Other removed features
1173 Various m68k-only ROM monitors.
1180 Various Renesas ROM monitors and debugging interfaces for SH and
1185 Support for a Macraigor serial interface to on-chip debugging.
1186 GDB does not directly support the newer parallel or USB
1191 A debug information format. The predecessor to DWARF 2 and
1192 DWARF 3, which are still supported.
1194 Support for the HP aCC compiler on HP-UX/PA-RISC
1196 SOM-encapsulated symbolic debugging information, automatic
1197 invocation of pxdb, and the aCC custom C++ ABI. This does not
1198 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1199 with aCC can still be debugged on an assembly level.
1201 MIPS ".pdr" sections
1203 A MIPS-specific format used to describe stack frame layout
1204 in debugging information.
1208 GDB could work with an older version of Guile to debug
1209 the interpreter and Scheme programs running in it.
1211 set mips stack-arg-size
1212 set mips saved-gpreg-size
1214 Use "set mips abi" to control parameter passing for MIPS.
1216 *** Changes in GDB 6.6
1221 Cell Broadband Engine SPU spu-elf
1223 * GDB can now be configured as a cross-debugger targeting native Windows
1224 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1225 running on a Windows system over TCP/IP to debug Windows programs.
1227 * The GDB remote stub, gdbserver, has been updated to support Windows and
1228 Cygwin debugging. Both single-threaded and multi-threaded programs are
1231 * The "set trust-readonly-sections" command works again. This command was
1232 broken in GDB 6.3, 6.4, and 6.5.
1234 * The "load" command now supports writing to flash memory, if the remote
1235 stub provides the required support.
1237 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1238 longer requires symbolic debug information (e.g. DWARF-2).
1243 unset substitute-path
1244 show substitute-path
1245 Manage a list of substitution rules that GDB uses to rewrite the name
1246 of the directories where the sources are located. This can be useful
1247 for instance when the sources were moved to a different location
1248 between compilation and debugging.
1252 Print each CLI command as it is executed. Each command is prefixed with
1253 a number of `+' symbols representing the nesting depth.
1254 The source command now has a `-v' option to enable the same feature.
1258 The ARM Demon monitor support (RDP protocol, "target rdp").
1260 Kernel Object Display, an embedded debugging feature which only worked with
1261 an obsolete version of Cisco IOS.
1263 The 'set download-write-size' and 'show download-write-size' commands.
1265 * New remote packets
1268 Tell a stub about GDB client features, and request remote target features.
1269 The first feature implemented is PacketSize, which allows the target to
1270 specify the size of packets it can handle - to minimize the number of
1271 packets required and improve performance when connected to a remote
1275 Fetch an OS auxilliary vector from the remote stub. This packet is a
1276 more efficient replacement for qPart:auxv:read.
1278 qXfer:memory-map:read:
1279 Fetch a memory map from the remote stub, including information about
1280 RAM, ROM, and flash memory devices.
1285 Erase and program a flash memory device.
1287 * Removed remote packets
1290 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1291 used it, and only gdbserver implemented it.
1293 *** Changes in GDB 6.5
1297 Renesas M32C/M16C m32c-elf
1299 Morpho Technologies ms1 ms1-elf
1303 init-if-undefined Initialize a convenience variable, but
1304 only if it doesn't already have a value.
1306 The following commands are presently only implemented for native GNU/Linux:
1308 checkpoint Save a snapshot of the program state.
1310 restart <n> Return the program state to a
1311 previously saved state.
1313 info checkpoints List currently saved checkpoints.
1315 delete-checkpoint <n> Delete a previously saved checkpoint.
1317 set|show detach-on-fork Tell gdb whether to detach from a newly
1318 forked process, or to keep debugging it.
1320 info forks List forks of the user program that
1321 are available to be debugged.
1323 fork <n> Switch to debugging one of several
1324 forks of the user program that are
1325 available to be debugged.
1327 delete-fork <n> Delete a fork from the list of forks
1328 that are available to be debugged (and
1329 kill the forked process).
1331 detach-fork <n> Delete a fork from the list of forks
1332 that are available to be debugged (and
1333 allow the process to continue).
1337 Morpho Technologies ms2 ms1-elf
1339 * Improved Windows host support
1341 GDB now builds as a cross debugger hosted on i686-mingw32, including
1342 native console support, and remote communications using either
1343 network sockets or serial ports.
1345 * Improved Modula-2 language support
1347 GDB can now print most types in the Modula-2 syntax. This includes:
1348 basic types, set types, record types, enumerated types, range types,
1349 pointer types and ARRAY types. Procedure var parameters are correctly
1350 printed and hexadecimal addresses and character constants are also
1351 written in the Modula-2 syntax. Best results can be obtained by using
1352 GNU Modula-2 together with the -gdwarf-2 command line option.
1356 The ARM rdi-share module.
1358 The Netware NLM debug server.
1360 *** Changes in GDB 6.4
1362 * New native configurations
1364 OpenBSD/arm arm*-*-openbsd*
1365 OpenBSD/mips64 mips64-*-openbsd*
1369 Morpho Technologies ms1 ms1-elf
1371 * New command line options
1373 --batch-silent As for --batch, but totally silent.
1374 --return-child-result The debugger will exist with the same value
1375 the child (debugged) program exited with.
1376 --eval-command COMMAND, -ex COMMAND
1377 Execute a single GDB CLI command. This may be
1378 specified multiple times and in conjunction
1379 with the --command (-x) option.
1381 * Deprecated commands removed
1383 The following commands, that were deprecated in 2000, have been
1387 set|show arm disassembly-flavor set|show arm disassembler
1388 othernames set arm disassembler
1389 set|show remotedebug set|show debug remote
1390 set|show archdebug set|show debug arch
1391 set|show eventdebug set|show debug event
1394 * New BSD user-level threads support
1396 It is now possible to debug programs using the user-level threads
1397 library on OpenBSD and FreeBSD. Currently supported (target)
1400 FreeBSD/amd64 x86_64-*-freebsd*
1401 FreeBSD/i386 i386-*-freebsd*
1402 OpenBSD/i386 i386-*-openbsd*
1404 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1405 are not yet supported.
1407 * New support for Matsushita MN10300 w/sim added
1408 (Work in progress). mn10300-elf.
1410 * REMOVED configurations and files
1412 VxWorks and the XDR protocol *-*-vxworks
1413 Motorola MCORE mcore-*-*
1414 National Semiconductor NS32000 ns32k-*-*
1416 * New "set print array-indexes" command
1418 After turning this setting "on", GDB prints the index of each element
1419 when displaying arrays. The default is "off" to preserve the previous
1422 * VAX floating point support
1424 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1426 * User-defined command support
1428 In addition to using $arg0..$arg9 for argument passing, it is now possible
1429 to use $argc to determine now many arguments have been passed. See the
1430 section on user-defined commands in the user manual for more information.
1432 *** Changes in GDB 6.3:
1434 * New command line option
1436 GDB now accepts -l followed by a number to set the timeout for remote
1439 * GDB works with GCC -feliminate-dwarf2-dups
1441 GDB now supports a more compact representation of DWARF-2 debug
1442 information using DW_FORM_ref_addr references. These are produced
1443 by GCC with the option -feliminate-dwarf2-dups and also by some
1444 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1445 to use -feliminate-dwarf2-dups.
1447 * Internationalization
1449 When supported by the host system, GDB will be built with
1450 internationalization (libintl). The task of marking up the sources is
1451 continued, we're looking forward to our first translation.
1455 Initial support for debugging programs compiled with the GNAT
1456 implementation of the Ada programming language has been integrated
1457 into GDB. In this release, support is limited to expression evaluation.
1459 * New native configurations
1461 GNU/Linux/m32r m32r-*-linux-gnu
1465 GDB's remote protocol now includes support for the 'p' packet. This
1466 packet is used to fetch individual registers from a remote inferior.
1468 * END-OF-LIFE registers[] compatibility module
1470 GDB's internal register infrastructure has been completely rewritten.
1471 The new infrastructure making possible the implementation of key new
1472 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1475 GDB 6.3 will be the last release to include the the registers[]
1476 compatibility module that allowed out-of-date configurations to
1477 continue to work. This change directly impacts the following
1487 powerpc bdm protocol
1489 Unless there is activity to revive these configurations, they will be
1490 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1492 * OBSOLETE configurations and files
1494 Configurations that have been declared obsolete in this release have
1495 been commented out. Unless there is activity to revive these
1496 configurations, the next release of GDB will have their sources
1497 permanently REMOVED.
1506 *** Changes in GDB 6.2.1:
1508 * MIPS `break main; run' gave an heuristic-fence-post warning
1510 When attempting to run even a simple program, a warning about
1511 heuristic-fence-post being hit would be reported. This problem has
1514 * MIPS IRIX 'long double' crashed GDB
1516 When examining a long double variable, GDB would get a segmentation
1517 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1518 IRIX long double values).
1522 A bug in the VAX stack code was causing problems with the "next"
1523 command. This problem has been fixed.
1525 *** Changes in GDB 6.2:
1527 * Fix for ``many threads''
1529 On GNU/Linux systems that use the NPTL threads library, a program
1530 rapidly creating and deleting threads would confuse GDB leading to the
1533 ptrace: No such process.
1534 thread_db_get_info: cannot get thread info: generic error
1536 This problem has been fixed.
1538 * "-async" and "-noasync" options removed.
1540 Support for the broken "-noasync" option has been removed (it caused
1543 * New ``start'' command.
1545 This command runs the program until the begining of the main procedure.
1547 * New BSD Kernel Data Access Library (libkvm) interface
1549 Using ``target kvm'' it is now possible to debug kernel core dumps and
1550 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1551 platforms. Currently supported (native-only) configurations are:
1553 FreeBSD/amd64 x86_64-*-freebsd*
1554 FreeBSD/i386 i?86-*-freebsd*
1555 NetBSD/i386 i?86-*-netbsd*
1556 NetBSD/m68k m68*-*-netbsd*
1557 NetBSD/sparc sparc-*-netbsd*
1558 OpenBSD/amd64 x86_64-*-openbsd*
1559 OpenBSD/i386 i?86-*-openbsd*
1560 OpenBSD/m68k m68*-openbsd*
1561 OpenBSD/sparc sparc-*-openbsd*
1563 * Signal trampoline code overhauled
1565 Many generic problems with GDB's signal handling code have been fixed.
1566 These include: backtraces through non-contiguous stacks; recognition
1567 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1568 call; backtrace through a signal trampoline; step into and out of
1569 signal handlers; and single-stepping in the signal trampoline.
1571 Please note that kernel bugs are a limiting factor here. These
1572 features have been shown to work on an s390 GNU/Linux system that
1573 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1575 * Cygwin support for DWARF 2 added.
1577 * New native configurations
1579 GNU/Linux/hppa hppa*-*-linux*
1580 OpenBSD/hppa hppa*-*-openbsd*
1581 OpenBSD/m68k m68*-*-openbsd*
1582 OpenBSD/m88k m88*-*-openbsd*
1583 OpenBSD/powerpc powerpc-*-openbsd*
1584 NetBSD/vax vax-*-netbsd*
1585 OpenBSD/vax vax-*-openbsd*
1587 * END-OF-LIFE frame compatibility module
1589 GDB's internal frame infrastructure has been completely rewritten.
1590 The new infrastructure making it possible to support key new features
1591 including DWARF 2 Call Frame Information. To aid in the task of
1592 migrating old configurations to this new infrastructure, a
1593 compatibility module, that allowed old configurations to continue to
1594 work, was also included.
1596 GDB 6.2 will be the last release to include this frame compatibility
1597 module. This change directly impacts the following configurations:
1607 Unless there is activity to revive these configurations, they will be
1608 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1610 * REMOVED configurations and files
1612 Sun 3, running SunOS 3 m68*-*-sunos3*
1613 Sun 3, running SunOS 4 m68*-*-sunos4*
1614 Sun 2, running SunOS 3 m68000-*-sunos3*
1615 Sun 2, running SunOS 4 m68000-*-sunos4*
1616 Motorola 680x0 running LynxOS m68*-*-lynxos*
1617 AT&T 3b1/Unix pc m68*-att-*
1618 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1619 decstation mips-dec-* mips-little-*
1620 riscos mips-*-riscos* mips-*-sysv*
1621 sonymips mips-sony-*
1622 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1624 *** Changes in GDB 6.1.1:
1626 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1628 The TUI (Text-mode User Interface) is now built as part of a default
1629 GDB configuration. It is enabled by either selecting the TUI with the
1630 command line option "-i=tui" or by running the separate "gdbtui"
1631 program. For more information on the TUI, see the manual "Debugging
1634 * Pending breakpoint support (also included in GDB 6.1)
1636 Support has been added to allow you to specify breakpoints in shared
1637 libraries that have not yet been loaded. If a breakpoint location
1638 cannot be found, and the "breakpoint pending" option is set to auto,
1639 GDB queries you if you wish to make the breakpoint pending on a future
1640 shared-library load. If and when GDB resolves the breakpoint symbol,
1641 the pending breakpoint is removed as one or more regular breakpoints
1644 Pending breakpoints are very useful for GCJ Java debugging.
1646 * Fixed ISO-C build problems
1648 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1649 non ISO-C code that stopped them being built using a more strict ISO-C
1650 compiler (e.g., IBM's C compiler).
1652 * Fixed build problem on IRIX 5
1654 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1655 wasn't able to compile compile on an IRIX 5 system.
1657 * Added execute permission to gdb/gdbserver/configure
1659 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1660 permission. This bug would cause configure to fail on a number of
1661 systems (Solaris, IRIX). Ref: server/519.
1663 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1665 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1666 has been updated to use constant array sizes.
1668 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1670 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1671 its generated DWARF Call Frame Info. This encoding was causing GDB to
1672 panic, that panic has been fixed. Ref: gdb/1628.
1674 * Fixed a problem when examining parameters in shared library code.
1676 When examining parameters in optimized shared library code generated
1677 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1678 not available''. GDB now correctly displays the variable's value.
1680 *** Changes in GDB 6.1:
1682 * Removed --with-mmalloc
1684 Support for the mmalloc memory manager has been removed, as it
1685 conflicted with the internal gdb byte cache.
1687 * Changes in AMD64 configurations
1689 The AMD64 target now includes the %cs and %ss registers. As a result
1690 the AMD64 remote protocol has changed; this affects the floating-point
1691 and SSE registers. If you rely on those registers for your debugging,
1692 you should upgrade gdbserver on the remote side.
1694 * Revised SPARC target
1696 The SPARC target has been completely revised, incorporating the
1697 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1698 support for LynxOS and SunOS 4 has been dropped. Calling functions
1699 from within GDB on operating systems with a non-executable stack
1700 (Solaris, OpenBSD) now works.
1704 GDB has a new C++ demangler which does a better job on the mangled
1705 names generated by current versions of g++. It also runs faster, so
1706 with this and other changes gdb should now start faster on large C++
1709 * DWARF 2 Location Expressions
1711 GDB support for location expressions has been extended to support function
1712 arguments and frame bases. Older versions of GDB could crash when they
1715 * C++ nested types and namespaces
1717 GDB's support for nested types and namespaces in C++ has been
1718 improved, especially if you use the DWARF 2 debugging format. (This
1719 is the default for recent versions of GCC on most platforms.)
1720 Specifically, if you have a class "Inner" defined within a class or
1721 namespace "Outer", then GDB realizes that the class's name is
1722 "Outer::Inner", not simply "Inner". This should greatly reduce the
1723 frequency of complaints about not finding RTTI symbols. In addition,
1724 if you are stopped at inside of a function defined within a namespace,
1725 GDB modifies its name lookup accordingly.
1727 * New native configurations
1729 NetBSD/amd64 x86_64-*-netbsd*
1730 OpenBSD/amd64 x86_64-*-openbsd*
1731 OpenBSD/alpha alpha*-*-openbsd*
1732 OpenBSD/sparc sparc-*-openbsd*
1733 OpenBSD/sparc64 sparc64-*-openbsd*
1735 * New debugging protocols
1737 M32R with SDI protocol m32r-*-elf*
1739 * "set prompt-escape-char" command deleted.
1741 The command "set prompt-escape-char" has been deleted. This command,
1742 and its very obscure effet on GDB's prompt, was never documented,
1743 tested, nor mentioned in the NEWS file.
1745 * OBSOLETE configurations and files
1747 Configurations that have been declared obsolete in this release have
1748 been commented out. Unless there is activity to revive these
1749 configurations, the next release of GDB will have their sources
1750 permanently REMOVED.
1752 Sun 3, running SunOS 3 m68*-*-sunos3*
1753 Sun 3, running SunOS 4 m68*-*-sunos4*
1754 Sun 2, running SunOS 3 m68000-*-sunos3*
1755 Sun 2, running SunOS 4 m68000-*-sunos4*
1756 Motorola 680x0 running LynxOS m68*-*-lynxos*
1757 AT&T 3b1/Unix pc m68*-att-*
1758 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1759 decstation mips-dec-* mips-little-*
1760 riscos mips-*-riscos* mips-*-sysv*
1761 sonymips mips-sony-*
1762 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1764 * REMOVED configurations and files
1766 SGI Irix-4.x mips-sgi-irix4 or iris4
1767 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1768 Z8000 simulator z8k-zilog-none or z8ksim
1769 Matsushita MN10200 w/simulator mn10200-*-*
1770 H8/500 simulator h8500-hitachi-hms or h8500hms
1771 HP/PA running BSD hppa*-*-bsd*
1772 HP/PA running OSF/1 hppa*-*-osf*
1773 HP/PA Pro target hppa*-*-pro*
1774 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1775 386BSD i[3456]86-*-bsd*
1776 Sequent family i[3456]86-sequent-sysv4*
1777 i[3456]86-sequent-sysv*
1778 i[3456]86-sequent-bsd*
1779 SPARC running LynxOS sparc-*-lynxos*
1780 SPARC running SunOS 4 sparc-*-sunos4*
1781 Tsqware Sparclet sparclet-*-*
1782 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1784 *** Changes in GDB 6.0:
1788 Support for debugging the Objective-C programming language has been
1789 integrated into GDB.
1791 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1793 DWARF 2's Call Frame Information makes available compiler generated
1794 information that more exactly describes the program's run-time stack.
1795 By using this information, GDB is able to provide more robust stack
1798 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1799 have been updated to use a new backtrace mechanism which includes
1800 DWARF 2 CFI support.
1804 GDB's remote protocol has been extended to include support for hosted
1805 file I/O (where the remote target uses GDB's file system). See GDB's
1806 remote protocol documentation for details.
1808 * All targets using the new architecture framework.
1810 All of GDB's targets have been updated to use the new internal
1811 architecture framework. The way is now open for future GDB releases
1812 to include cross-architecture native debugging support (i386 on amd64,
1815 * GNU/Linux's Thread Local Storage (TLS)
1817 GDB now includes support for for the GNU/Linux implementation of
1818 per-thread variables.
1820 * GNU/Linux's Native POSIX Thread Library (NPTL)
1822 GDB's thread code has been updated to work with either the new
1823 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1825 * Separate debug info.
1827 GDB, in conjunction with BINUTILS, now supports a mechanism for
1828 automatically loading debug information from a separate file. Instead
1829 of shipping full debug and non-debug versions of system libraries,
1830 system integrators can now instead ship just the stripped libraries
1831 and optional debug files.
1833 * DWARF 2 Location Expressions
1835 DWARF 2 Location Expressions allow the compiler to more completely
1836 describe the location of variables (even in optimized code) to the
1839 GDB now includes preliminary support for location expressions (support
1840 for DW_OP_piece is still missing).
1844 A number of long standing bugs that caused GDB to die while starting a
1845 Java application have been fixed. GDB's Java support is now
1846 considered "useable".
1848 * GNU/Linux support for fork, vfork, and exec.
1850 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1851 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1854 * GDB supports logging output to a file
1856 There are two new commands, "set logging" and "show logging", which can be
1857 used to capture GDB's output to a file.
1859 * The meaning of "detach" has changed for gdbserver
1861 The "detach" command will now resume the application, as documented. To
1862 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1865 * d10v, m68hc11 `regs' command deprecated
1867 The `info registers' command has been updated so that it displays the
1868 registers using a format identical to the old `regs' command.
1872 A new command, "maint set profile on/off", has been added. This command can
1873 be used to enable or disable profiling while running GDB, to profile a
1874 session or a set of commands. In addition there is a new configure switch,
1875 "--enable-profiling", which will cause GDB to be compiled with profiling
1876 data, for more informative profiling results.
1878 * Default MI syntax changed to "mi2".
1880 The default MI (machine interface) syntax, enabled by the command line
1881 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1882 "mi1", can be enabled by specifying the option "-i=mi1".
1884 Support for the original "mi0" syntax (included in GDB 5.0) has been
1887 Fix for gdb/192: removed extraneous space when displaying frame level.
1888 Fix for gdb/672: update changelist is now output in mi list format.
1889 Fix for gdb/702: a -var-assign that updates the value now shows up
1890 in a subsequent -var-update.
1892 * New native configurations.
1894 FreeBSD/amd64 x86_64-*-freebsd*
1896 * Multi-arched targets.
1898 HP/PA HPUX11 hppa*-*-hpux*
1899 Renesas M32R/D w/simulator m32r-*-elf*
1901 * OBSOLETE configurations and files
1903 Configurations that have been declared obsolete in this release have
1904 been commented out. Unless there is activity to revive these
1905 configurations, the next release of GDB will have their sources
1906 permanently REMOVED.
1908 Z8000 simulator z8k-zilog-none or z8ksim
1909 Matsushita MN10200 w/simulator mn10200-*-*
1910 H8/500 simulator h8500-hitachi-hms or h8500hms
1911 HP/PA running BSD hppa*-*-bsd*
1912 HP/PA running OSF/1 hppa*-*-osf*
1913 HP/PA Pro target hppa*-*-pro*
1914 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1915 Sequent family i[3456]86-sequent-sysv4*
1916 i[3456]86-sequent-sysv*
1917 i[3456]86-sequent-bsd*
1918 Tsqware Sparclet sparclet-*-*
1919 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1921 * REMOVED configurations and files
1924 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1925 IBM AIX PS/2 i[3456]86-*-aix
1926 i386 running Mach 3.0 i[3456]86-*-mach3*
1927 i386 running Mach i[3456]86-*-mach*
1928 i386 running OSF/1 i[3456]86-*osf1mk*
1929 HP/Apollo 68k Family m68*-apollo*-sysv*,
1931 m68*-hp-bsd*, m68*-hp-hpux*
1932 Argonaut Risc Chip (ARC) arc-*-*
1933 Mitsubishi D30V d30v-*-*
1934 Fujitsu FR30 fr30-*-elf*
1935 OS/9000 i[34]86-*-os9k
1936 I960 with MON960 i960-*-coff
1938 * MIPS $fp behavior changed
1940 The convenience variable $fp, for the MIPS, now consistently returns
1941 the address of the current frame's base. Previously, depending on the
1942 context, $fp could refer to either $sp or the current frame's base
1943 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1944 The GNU Source-Level Debugger''.
1946 *** Changes in GDB 5.3:
1948 * GNU/Linux shared library multi-threaded performance improved.
1950 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1951 `/proc', in preference to `ptrace' for memory reads. This may result
1952 in an improvement in the start-up time of multi-threaded, shared
1953 library applications when run under GDB. One GDB user writes: ``loads
1954 shared libs like mad''.
1956 * ``gdbserver'' now supports multi-threaded applications on some targets
1958 Support for debugging multi-threaded applications which use
1959 the GNU/Linux LinuxThreads package has been added for
1960 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1961 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1963 * GDB now supports C/C++ preprocessor macros.
1965 GDB now expands preprocessor macro invocations in C/C++ expressions,
1966 and provides various commands for showing macro definitions and how
1969 The new command `macro expand EXPRESSION' expands any macro
1970 invocations in expression, and shows the result.
1972 The new command `show macro MACRO-NAME' shows the definition of the
1973 macro named MACRO-NAME, and where it was defined.
1975 Most compilers don't include information about macros in the debugging
1976 information by default. In GCC 3.1, for example, you need to compile
1977 your program with the options `-gdwarf-2 -g3'. If the macro
1978 information is present in the executable, GDB will read it.
1980 * Multi-arched targets.
1982 DEC Alpha (partial) alpha*-*-*
1983 DEC VAX (partial) vax-*-*
1985 National Semiconductor NS32000 (partial) ns32k-*-*
1986 Motorola 68000 (partial) m68k-*-*
1987 Motorola MCORE mcore-*-*
1991 Fujitsu FRV architecture added by Red Hat frv*-*-*
1994 * New native configurations
1996 Alpha NetBSD alpha*-*-netbsd*
1997 SH NetBSD sh*-*-netbsdelf*
1998 MIPS NetBSD mips*-*-netbsd*
1999 UltraSPARC NetBSD sparc64-*-netbsd*
2001 * OBSOLETE configurations and files
2003 Configurations that have been declared obsolete in this release have
2004 been commented out. Unless there is activity to revive these
2005 configurations, the next release of GDB will have their sources
2006 permanently REMOVED.
2008 Mitsubishi D30V d30v-*-*
2009 OS/9000 i[34]86-*-os9k
2010 IBM AIX PS/2 i[3456]86-*-aix
2011 Fujitsu FR30 fr30-*-elf*
2012 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2013 Argonaut Risc Chip (ARC) arc-*-*
2014 i386 running Mach 3.0 i[3456]86-*-mach3*
2015 i386 running Mach i[3456]86-*-mach*
2016 i386 running OSF/1 i[3456]86-*osf1mk*
2017 HP/Apollo 68k Family m68*-apollo*-sysv*,
2019 m68*-hp-bsd*, m68*-hp-hpux*
2020 I960 with MON960 i960-*-coff
2022 * OBSOLETE languages
2024 CHILL, a Pascal like language used by telecommunications companies.
2026 * REMOVED configurations and files
2028 AMD 29k family via UDI a29k-amd-udi, udi29k
2029 A29K VxWorks a29k-*-vxworks
2030 AMD 29000 embedded, using EBMON a29k-none-none
2031 AMD 29000 embedded with COFF a29k-none-coff
2032 AMD 29000 embedded with a.out a29k-none-aout
2034 testsuite/gdb.hp/gdb.threads-hp/ directory
2036 * New command "set max-user-call-depth <nnn>"
2038 This command allows the user to limit the call depth of user-defined
2039 commands. The default is 1024.
2041 * Changes in FreeBSD/i386 native debugging.
2043 Support for the "generate-core-file" has been added.
2045 * New commands "dump", "append", and "restore".
2047 These commands allow data to be copied from target memory
2048 to a bfd-format or binary file (dump and append), and back
2049 from a file into memory (restore).
2051 * Improved "next/step" support on multi-processor Alpha Tru64.
2053 The previous single-step mechanism could cause unpredictable problems,
2054 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2055 of a software single-step mechanism prevents this.
2057 *** Changes in GDB 5.2.1:
2065 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2066 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2067 Fix, by Joel Brobecker imported from mainline.
2069 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2070 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2071 Fix, by Fred Fish, imported from mainline.
2073 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2074 Surprisingly enough, it works now.
2075 By Michal Ludvig, imported from mainline.
2077 i386 hardware watchpoint support:
2078 avoid misses on second run for some targets.
2079 By Pierre Muller, imported from mainline.
2081 *** Changes in GDB 5.2:
2083 * New command "set trust-readonly-sections on[off]".
2085 This command is a hint that tells gdb that read-only sections
2086 really are read-only (ie. that their contents will not change).
2087 In this mode, gdb will go to the object file rather than the
2088 target to read memory from read-only sections (such as ".text").
2089 This can be a significant performance improvement on some
2090 (notably embedded) targets.
2092 * New command "generate-core-file" (or "gcore").
2094 This new gdb command allows the user to drop a core file of the child
2095 process state at any time. So far it's been implemented only for
2096 GNU/Linux and Solaris, but should be relatively easily ported to other
2097 hosts. Argument is core file name (defaults to core.<pid>).
2099 * New command line option
2101 GDB now accepts --pid or -p followed by a process id.
2103 * Change in command line behavior -- corefiles vs. process ids.
2105 There is a subtle behavior in the way in which GDB handles
2106 command line arguments. The first non-flag argument is always
2107 a program to debug, but the second non-flag argument may either
2108 be a corefile or a process id. Previously, GDB would attempt to
2109 open the second argument as a corefile, and if that failed, would
2110 issue a superfluous error message and then attempt to attach it as
2111 a process. Now, if the second argument begins with a non-digit,
2112 it will be treated as a corefile. If it begins with a digit,
2113 GDB will attempt to attach it as a process, and if no such process
2114 is found, will then attempt to open it as a corefile.
2116 * Changes in ARM configurations.
2118 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2119 configuration is fully multi-arch.
2121 * New native configurations
2123 ARM NetBSD arm*-*-netbsd*
2124 x86 OpenBSD i[3456]86-*-openbsd*
2125 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2126 Sparc64 running FreeBSD sparc64-*-freebsd*
2130 Sanyo XStormy16 xstormy16-elf
2132 * OBSOLETE configurations and files
2134 Configurations that have been declared obsolete in this release have
2135 been commented out. Unless there is activity to revive these
2136 configurations, the next release of GDB will have their sources
2137 permanently REMOVED.
2139 AMD 29k family via UDI a29k-amd-udi, udi29k
2140 A29K VxWorks a29k-*-vxworks
2141 AMD 29000 embedded, using EBMON a29k-none-none
2142 AMD 29000 embedded with COFF a29k-none-coff
2143 AMD 29000 embedded with a.out a29k-none-aout
2145 testsuite/gdb.hp/gdb.threads-hp/ directory
2147 * REMOVED configurations and files
2149 TI TMS320C80 tic80-*-*
2151 PowerPC Solaris powerpcle-*-solaris*
2152 PowerPC Windows NT powerpcle-*-cygwin32
2153 PowerPC Netware powerpc-*-netware*
2154 Harris/CXUX m88k m88*-harris-cxux*
2155 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2156 ns32k-utek-sysv* ns32k-utek-*
2157 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2158 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2159 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2160 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2161 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2163 * Changes to command line processing
2165 The new `--args' feature can be used to specify command-line arguments
2166 for the inferior from gdb's command line.
2168 * Changes to key bindings
2170 There is a new `operate-and-get-next' function bound to `C-o'.
2172 *** Changes in GDB 5.1.1
2174 Fix compile problem on DJGPP.
2176 Fix a problem with floating-point registers on the i386 being
2179 Fix to stop GDB crashing on .debug_str debug info.
2181 Numerous documentation fixes.
2183 Numerous testsuite fixes.
2185 *** Changes in GDB 5.1:
2187 * New native configurations
2189 Alpha FreeBSD alpha*-*-freebsd*
2190 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2191 MIPS GNU/Linux mips*-*-linux*
2192 MIPS SGI Irix 6.x mips*-sgi-irix6*
2193 ia64 AIX ia64-*-aix*
2194 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2198 Motorola 68HC11 and 68HC12 m68hc11-elf
2200 UltraSparc running GNU/Linux sparc64-*-linux*
2202 * OBSOLETE configurations and files
2204 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2205 Harris/CXUX m88k m88*-harris-cxux*
2206 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2207 ns32k-utek-sysv* ns32k-utek-*
2208 TI TMS320C80 tic80-*-*
2210 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2211 PowerPC Solaris powerpcle-*-solaris*
2212 PowerPC Windows NT powerpcle-*-cygwin32
2213 PowerPC Netware powerpc-*-netware*
2214 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2215 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2216 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2217 Apple Macintosh (MPW) host N/A
2219 stuff.c (Program to stuff files into a specially prepared space in kdb)
2220 kdb-start.c (Main loop for the standalone kernel debugger)
2222 Configurations that have been declared obsolete in this release have
2223 been commented out. Unless there is activity to revive these
2224 configurations, the next release of GDB will have their sources
2225 permanently REMOVED.
2227 * REMOVED configurations and files
2229 Altos 3068 m68*-altos-*
2230 Convex c1-*-*, c2-*-*
2232 ARM RISCix arm-*-* (as host)
2236 * GDB has been converted to ISO C.
2238 GDB's source code has been converted to ISO C. In particular, the
2239 sources are fully protoized, and rely on standard headers being
2244 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2246 * The MI enabled by default.
2248 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2249 revised and enabled by default. Packages which use GDB as a debugging
2250 engine behind a UI or another front end are encouraged to switch to
2251 using the GDB/MI interface, instead of the old annotations interface
2252 which is now deprecated.
2254 * Support for debugging Pascal programs.
2256 GDB now includes support for debugging Pascal programs. The following
2257 main features are supported:
2259 - Pascal-specific data types such as sets;
2261 - automatic recognition of Pascal sources based on file-name
2264 - Pascal-style display of data types, variables, and functions;
2266 - a Pascal expression parser.
2268 However, some important features are not yet supported.
2270 - Pascal string operations are not supported at all;
2272 - there are some problems with boolean types;
2274 - Pascal type hexadecimal constants are not supported
2275 because they conflict with the internal variables format;
2277 - support for Pascal objects and classes is not full yet;
2279 - unlike Pascal, GDB is case-sensitive for symbol names.
2281 * Changes in completion.
2283 Commands such as `shell', `run' and `set args', which pass arguments
2284 to inferior programs, now complete on file names, similar to what
2285 users expect at the shell prompt.
2287 Commands which accept locations, such as `disassemble', `print',
2288 `breakpoint', `until', etc. now complete on filenames as well as
2289 program symbols. Thus, if you type "break foob TAB", and the source
2290 files linked into the programs include `foobar.c', that file name will
2291 be one of the candidates for completion. However, file names are not
2292 considered for completion after you typed a colon that delimits a file
2293 name from a name of a function in that file, as in "break foo.c:bar".
2295 `set demangle-style' completes on available demangling styles.
2297 * New platform-independent commands:
2299 It is now possible to define a post-hook for a command as well as a
2300 hook that runs before the command. For more details, see the
2301 documentation of `hookpost' in the GDB manual.
2303 * Changes in GNU/Linux native debugging.
2305 Support for debugging multi-threaded programs has been completely
2306 revised for all platforms except m68k and sparc. You can now debug as
2307 many threads as your system allows you to have.
2309 Attach/detach is supported for multi-threaded programs.
2311 Support for SSE registers was added for x86. This doesn't work for
2312 multi-threaded programs though.
2314 * Changes in MIPS configurations.
2316 Multi-arch support is enabled for all MIPS configurations.
2318 GDB can now be built as native debugger on SGI Irix 6.x systems for
2319 debugging n32 executables. (Debugging 64-bit executables is not yet
2322 * Unified support for hardware watchpoints in all x86 configurations.
2324 Most (if not all) native x86 configurations support hardware-assisted
2325 breakpoints and watchpoints in a unified manner. This support
2326 implements debug register sharing between watchpoints, which allows to
2327 put a virtually infinite number of watchpoints on the same address,
2328 and also supports watching regions up to 16 bytes with several debug
2331 The new maintenance command `maintenance show-debug-regs' toggles
2332 debugging print-outs in functions that insert, remove, and test
2333 watchpoints and hardware breakpoints.
2335 * Changes in the DJGPP native configuration.
2337 New command ``info dos sysinfo'' displays assorted information about
2338 the CPU, OS, memory, and DPMI server.
2340 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2341 display information about segment descriptors stored in GDT, LDT, and
2344 New commands ``info dos pde'' and ``info dos pte'' display entries
2345 from Page Directory and Page Tables (for now works with CWSDPMI only).
2346 New command ``info dos address-pte'' displays the Page Table entry for
2347 a given linear address.
2349 GDB can now pass command lines longer than 126 characters to the
2350 program being debugged (requires an update to the libdbg.a library
2351 which is part of the DJGPP development kit).
2353 DWARF2 debug info is now supported.
2355 It is now possible to `step' and `next' through calls to `longjmp'.
2357 * Changes in documentation.
2359 All GDB documentation was converted to GFDL, the GNU Free
2360 Documentation License.
2362 Tracepoints-related commands are now fully documented in the GDB
2365 TUI, the Text-mode User Interface, is now documented in the manual.
2367 Tracepoints-related commands are now fully documented in the GDB
2370 The "GDB Internals" manual now has an index. It also includes
2371 documentation of `ui_out' functions, GDB coding standards, x86
2372 hardware watchpoints, and memory region attributes.
2374 * GDB's version number moved to ``version.in''
2376 The Makefile variable VERSION has been replaced by the file
2377 ``version.in''. People creating GDB distributions should update the
2378 contents of this file.
2382 GUD support is now a standard part of the EMACS distribution.
2384 *** Changes in GDB 5.0:
2386 * Improved support for debugging FP programs on x86 targets
2388 Unified and much-improved support for debugging floating-point
2389 programs on all x86 targets. In particular, ``info float'' now
2390 displays the FP registers in the same format on all x86 targets, with
2391 greater level of detail.
2393 * Improvements and bugfixes in hardware-assisted watchpoints
2395 It is now possible to watch array elements, struct members, and
2396 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2397 on x86 targets no longer erroneously trigger when the address is
2400 * Improvements in the native DJGPP version of GDB
2402 The distribution now includes all the scripts and auxiliary files
2403 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2404 machines ``out of the box''.
2406 The DJGPP version can now debug programs that use signals. It is
2407 possible to catch signals that happened in the debuggee, deliver
2408 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2409 would kill the program being debugged.) Programs that hook hardware
2410 interrupts (keyboard, timer, etc.) can also be debugged.
2412 It is now possible to debug DJGPP programs that redirect their
2413 standard handles or switch them to raw (as opposed to cooked) mode, or
2414 even close them. The command ``run < foo > bar'' works as expected,
2415 and ``info terminal'' reports useful information about the debuggee's
2416 terminal, including raw/cooked mode, redirection, etc.
2418 The DJGPP version now uses termios functions for console I/O, which
2419 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2422 DOS-style file names with drive letters are now fully supported by
2425 It is now possible to debug DJGPP programs that switch their working
2426 directory. It is also possible to rerun the debuggee any number of
2427 times without restarting GDB; thus, you can use the same setup,
2428 breakpoints, etc. for many debugging sessions.
2430 * New native configurations
2432 ARM GNU/Linux arm*-*-linux*
2433 PowerPC GNU/Linux powerpc-*-linux*
2437 Motorola MCore mcore-*-*
2438 x86 VxWorks i[3456]86-*-vxworks*
2439 PowerPC VxWorks powerpc-*-vxworks*
2440 TI TMS320C80 tic80-*-*
2442 * OBSOLETE configurations
2444 Altos 3068 m68*-altos-*
2445 Convex c1-*-*, c2-*-*
2447 ARM RISCix arm-*-* (as host)
2450 Configurations that have been declared obsolete will be commented out,
2451 but the code will be left in place. If there is no activity to revive
2452 these configurations before the next release of GDB, the sources will
2453 be permanently REMOVED.
2455 * Gould support removed
2457 Support for the Gould PowerNode and NP1 has been removed.
2459 * New features for SVR4
2461 On SVR4 native platforms (such as Solaris), if you attach to a process
2462 without first loading a symbol file, GDB will now attempt to locate and
2463 load symbols from the running process's executable file.
2465 * Many C++ enhancements
2467 C++ support has been greatly improved. Overload resolution now works properly
2468 in almost all cases. RTTI support is on the way.
2470 * Remote targets can connect to a sub-program
2472 A popen(3) style serial-device has been added. This device starts a
2473 sub-process (such as a stand-alone simulator) and then communicates
2474 with that. The sub-program to run is specified using the syntax
2475 ``|<program> <args>'' vis:
2477 (gdb) set remotedebug 1
2478 (gdb) target extended-remote |mn10300-elf-sim program-args
2480 * MIPS 64 remote protocol
2482 A long standing bug in the mips64 remote protocol where by GDB
2483 expected certain 32 bit registers (ex SR) to be transfered as 32
2484 instead of 64 bits has been fixed.
2486 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2487 added to provide backward compatibility with older versions of GDB.
2489 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2491 The command ``set remotebinarydownload'' command has been replaced by
2492 ``set remote X-packet''. Other commands in ``set remote'' family
2493 include ``set remote P-packet''.
2495 * Breakpoint commands accept ranges.
2497 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2498 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2499 ``tracepoint passcount'' also accepts a range of tracepoints.
2501 * ``apropos'' command added.
2503 The ``apropos'' command searches through command names and
2504 documentation strings, printing out matches, making it much easier to
2505 try to find a command that does what you are looking for.
2509 A new machine oriented interface (MI) has been added to GDB. This
2510 interface is designed for debug environments running GDB as a separate
2511 process. This is part of the long term libGDB project. See the
2512 "GDB/MI" chapter of the GDB manual for further information. It can be
2513 enabled by configuring with:
2515 .../configure --enable-gdbmi
2517 *** Changes in GDB-4.18:
2519 * New native configurations
2521 HP-UX 10.20 hppa*-*-hpux10.20
2522 HP-UX 11.x hppa*-*-hpux11.0*
2523 M68K GNU/Linux m68*-*-linux*
2527 Fujitsu FR30 fr30-*-elf*
2528 Intel StrongARM strongarm-*-*
2529 Mitsubishi D30V d30v-*-*
2531 * OBSOLETE configurations
2533 Gould PowerNode, NP1 np1-*-*, pn-*-*
2535 Configurations that have been declared obsolete will be commented out,
2536 but the code will be left in place. If there is no activity to revive
2537 these configurations before the next release of GDB, the sources will
2538 be permanently REMOVED.
2542 As a compatibility experiment, GDB's source files buildsym.h and
2543 buildsym.c have been converted to pure standard C, no longer
2544 containing any K&R compatibility code. We believe that all systems in
2545 use today either come with a standard C compiler, or have a GCC port
2546 available. If this is not true, please report the affected
2547 configuration to bug-gdb@gnu.org immediately. See the README file for
2548 information about getting a standard C compiler if you don't have one
2553 GDB now uses readline 2.2.
2555 * set extension-language
2557 You can now control the mapping between filename extensions and source
2558 languages by using the `set extension-language' command. For instance,
2559 you can ask GDB to treat .c files as C++ by saying
2560 set extension-language .c c++
2561 The command `info extensions' lists all of the recognized extensions
2562 and their associated languages.
2564 * Setting processor type for PowerPC and RS/6000
2566 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2567 you can use the `set processor' command to specify what variant of the
2568 PowerPC family you are debugging. The command
2572 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2573 following PowerPC and RS6000 variants:
2575 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2576 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2578 403GC IBM PowerPC 403GC
2579 505 Motorola PowerPC 505
2580 860 Motorola PowerPC 860 or 850
2581 601 Motorola PowerPC 601
2582 602 Motorola PowerPC 602
2583 603 Motorola/IBM PowerPC 603 or 603e
2584 604 Motorola PowerPC 604 or 604e
2585 750 Motorola/IBM PowerPC 750 or 750
2587 At the moment, this command just tells GDB what to name the
2588 special-purpose processor registers. Since almost all the affected
2589 registers are inaccessible to user-level programs, this command is
2590 only useful for remote debugging in its present form.
2594 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2595 more extensive support for HP-UX. Added features include shared
2596 library support, kernel threads and hardware watchpoints for 11.00,
2597 support for HP's ANSI C and C++ compilers, and a compatibility mode
2598 for xdb and dbx commands.
2602 HP's donation includes the new concept of catchpoints, which is a
2603 generalization of the old catch command. On HP-UX, it is now possible
2604 to catch exec, fork, and vfork, as well as library loading.
2606 This means that the existing catch command has changed; its first
2607 argument now specifies the type of catch to be set up. See the
2608 output of "help catch" for a list of catchpoint types.
2610 * Debugging across forks
2612 On HP-UX, you can choose which process to debug when a fork() happens
2617 HP has donated a curses-based terminal user interface (TUI). To get
2618 it, build with --enable-tui. Although this can be enabled for any
2619 configuration, at present it only works for native HP debugging.
2621 * GDB remote protocol additions
2623 A new protocol packet 'X' that writes binary data is now available.
2624 Default behavior is to try 'X', then drop back to 'M' if the stub
2625 fails to respond. The settable variable `remotebinarydownload'
2626 allows explicit control over the use of 'X'.
2628 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2629 full 64-bit address. The command
2631 set remoteaddresssize 32
2633 can be used to revert to the old behaviour. For existing remote stubs
2634 the change should not be noticed, as the additional address information
2637 In order to assist in debugging stubs, you may use the maintenance
2638 command `packet' to send any text string to the stub. For instance,
2640 maint packet heythere
2642 sends the packet "$heythere#<checksum>". Note that it is very easy to
2643 disrupt a debugging session by sending the wrong packet at the wrong
2646 The compare-sections command allows you to compare section data on the
2647 target to what is in the executable file without uploading or
2648 downloading, by comparing CRC checksums.
2650 * Tracing can collect general expressions
2652 You may now collect general expressions at tracepoints. This requires
2653 further additions to the target-side stub; see tracepoint.c and
2654 doc/agentexpr.texi for further details.
2656 * mask-address variable for Mips
2658 For Mips targets, you may control the zeroing of the upper 32 bits of
2659 a 64-bit address by entering `set mask-address on'. This is mainly
2660 of interest to users of embedded R4xxx and R5xxx processors.
2662 * Higher serial baud rates
2664 GDB's serial code now allows you to specify baud rates 57600, 115200,
2665 230400, and 460800 baud. (Note that your host system may not be able
2666 to achieve all of these rates.)
2670 The i960 configuration now includes an initial implementation of a
2671 builtin simulator, contributed by Jim Wilson.
2674 *** Changes in GDB-4.17:
2676 * New native configurations
2678 Alpha GNU/Linux alpha*-*-linux*
2679 Unixware 2.x i[3456]86-unixware2*
2680 Irix 6.x mips*-sgi-irix6*
2681 PowerPC GNU/Linux powerpc-*-linux*
2682 PowerPC Solaris powerpcle-*-solaris*
2683 Sparc GNU/Linux sparc-*-linux*
2684 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2688 Argonaut Risc Chip (ARC) arc-*-*
2689 Hitachi H8/300S h8300*-*-*
2690 Matsushita MN10200 w/simulator mn10200-*-*
2691 Matsushita MN10300 w/simulator mn10300-*-*
2692 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2693 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2694 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2695 Mitsubishi D10V w/simulator d10v-*-*
2696 Mitsubishi M32R/D w/simulator m32r-*-elf*
2697 Tsqware Sparclet sparclet-*-*
2698 NEC V850 w/simulator v850-*-*
2700 * New debugging protocols
2702 ARM with RDI protocol arm*-*-*
2703 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2704 DDB and LSI variants of PMON protocol mips*-*-*
2705 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2706 PowerPC with SDS protocol powerpc{,le}-*-eabi
2707 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2711 All configurations can now understand and use the DWARF 2 debugging
2712 format. The choice is automatic, if the symbol file contains DWARF 2
2717 GDB now includes basic Java language support. This support is
2718 only useful with Java compilers that produce native machine code.
2720 * solib-absolute-prefix and solib-search-path
2722 For SunOS and SVR4 shared libraries, you may now set the prefix for
2723 loading absolute shared library symbol files, and the search path for
2724 locating non-absolute shared library symbol files.
2726 * Live range splitting
2728 GDB can now effectively debug code for which GCC has performed live
2729 range splitting as part of its optimization. See gdb/doc/LRS for
2730 more details on the expected format of the stabs information.
2734 GDB's support for the GNU Hurd, including thread debugging, has been
2735 updated to work with current versions of the Hurd.
2739 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2740 instruction set. ARM GDB automatically detects when Thumb
2741 instructions are in use, and adjusts disassembly and backtracing
2746 GDB's MIPS target configurations now handle the MIP16 16-bit
2751 GDB now includes support for overlays; if an executable has been
2752 linked such that multiple sections are based at the same address, GDB
2753 will decide which section to use for symbolic info. You can choose to
2754 control the decision manually, using overlay commands, or implement
2755 additional target-side support and use "overlay load-target" to bring
2756 in the overlay mapping. Do "help overlay" for more detail.
2760 The command "info symbol <address>" displays information about
2761 the symbol at the specified address.
2765 The standard remote protocol now includes an extension that allows
2766 asynchronous collection and display of trace data. This requires
2767 extensive support in the target-side debugging stub. Tracing mode
2768 includes a new interaction mode in GDB and new commands: see the
2769 file tracepoint.c for more details.
2773 Configurations for embedded MIPS now include a simulator contributed
2774 by Cygnus Solutions. The simulator supports the instruction sets
2775 of most MIPS variants.
2779 Sparc configurations may now include the ERC32 simulator contributed
2780 by the European Space Agency. The simulator is not built into
2781 Sparc targets by default; configure with --enable-sim to include it.
2785 For target configurations that may include multiple variants of a
2786 basic architecture (such as MIPS and SH), you may now set the
2787 architecture explicitly. "set arch" sets, "info arch" lists
2788 the possible architectures.
2790 *** Changes in GDB-4.16:
2792 * New native configurations
2794 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2795 M68K NetBSD m68k-*-netbsd*
2796 PowerPC AIX 4.x powerpc-*-aix*
2797 PowerPC MacOS powerpc-*-macos*
2798 PowerPC Windows NT powerpcle-*-cygwin32
2799 RS/6000 AIX 4.x rs6000-*-aix4*
2803 ARM with RDP protocol arm-*-*
2804 I960 with MON960 i960-*-coff
2805 MIPS VxWorks mips*-*-vxworks*
2806 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2807 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2809 Matra Sparclet sparclet-*-*
2813 The powerpc-eabi configuration now includes the PSIM simulator,
2814 contributed by Andrew Cagney, with assistance from Mike Meissner.
2815 PSIM is a very elaborate model of the PowerPC, including not only
2816 basic instruction set execution, but also details of execution unit
2817 performance and I/O hardware. See sim/ppc/README for more details.
2821 GDB now works with Solaris 2.5.
2823 * Windows 95/NT native
2825 GDB will now work as a native debugger on Windows 95 and Windows NT.
2826 To build it from source, you must use the "gnu-win32" environment,
2827 which uses a DLL to emulate enough of Unix to run the GNU tools.
2828 Further information, binaries, and sources are available at
2829 ftp.cygnus.com, under pub/gnu-win32.
2831 * dont-repeat command
2833 If a user-defined command includes the command `dont-repeat', then the
2834 command will not be repeated if the user just types return. This is
2835 useful if the command is time-consuming to run, so that accidental
2836 extra keystrokes don't run the same command many times.
2838 * Send break instead of ^C
2840 The standard remote protocol now includes an option to send a break
2841 rather than a ^C to the target in order to interrupt it. By default,
2842 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2844 * Remote protocol timeout
2846 The standard remote protocol includes a new variable `remotetimeout'
2847 that allows you to set the number of seconds before GDB gives up trying
2848 to read from the target. The default value is 2.
2850 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2852 By default GDB will automatically keep track of objects as they are
2853 loaded and unloaded by the dynamic linker. By using the command `set
2854 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2855 when shared library events occur, thus allowing you to set breakpoints
2856 in shared libraries which are explicitly loaded by the inferior.
2858 Note this feature does not work on hpux8. On hpux9 you must link
2859 /usr/lib/end.o into your program. This feature should work
2860 automatically on hpux10.
2862 * Irix 5.x hardware watchpoint support
2864 Irix 5 configurations now support the use of hardware watchpoints.
2866 * Mips protocol "SYN garbage limit"
2868 When debugging a Mips target using the `target mips' protocol, you
2869 may set the number of characters that GDB will ignore by setting
2870 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2871 every character. The default value is 1050.
2873 * Recording and replaying remote debug sessions
2875 If you set `remotelogfile' to the name of a file, gdb will write to it
2876 a recording of a remote debug session. This recording may then be
2877 replayed back to gdb using "gdbreplay". See gdbserver/README for
2878 details. This is useful when you have a problem with GDB while doing
2879 remote debugging; you can make a recording of the session and send it
2880 to someone else, who can then recreate the problem.
2882 * Speedups for remote debugging
2884 GDB includes speedups for downloading and stepping MIPS systems using
2885 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2886 and more efficient S-record downloading.
2888 * Memory use reductions and statistics collection
2890 GDB now uses less memory and reports statistics about memory usage.
2891 Try the `maint print statistics' command, for example.
2893 *** Changes in GDB-4.15:
2895 * Psymtabs for XCOFF
2897 The symbol reader for AIX GDB now uses partial symbol tables. This
2898 can greatly improve startup time, especially for large executables.
2900 * Remote targets use caching
2902 Remote targets now use a data cache to speed up communication with the
2903 remote side. The data cache could lead to incorrect results because
2904 it doesn't know about volatile variables, thus making it impossible to
2905 debug targets which use memory mapped I/O devices. `set remotecache
2906 off' turns the the data cache off.
2908 * Remote targets may have threads
2910 The standard remote protocol now includes support for multiple threads
2911 in the target system, using new protocol commands 'H' and 'T'. See
2912 gdb/remote.c for details.
2916 If GDB is configured with `--enable-netrom', then it will include
2917 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2918 acts as though it is a bank of ROM on the target board, but you can
2919 write into it over the network. GDB's support consists only of
2920 support for fast loading into the emulated ROM; to debug, you must use
2921 another protocol, such as standard remote protocol. The usual
2922 sequence is something like
2924 target nrom <netrom-hostname>
2926 target remote <netrom-hostname>:1235
2930 GDB now includes support for the Apple Macintosh, as a host only. It
2931 may be run as either an MPW tool or as a standalone application, and
2932 it can debug through the serial port. All the usual GDB commands are
2933 available, but to the target command, you must supply "serial" as the
2934 device type instead of "/dev/ttyXX". See mpw-README in the main
2935 directory for more information on how to build. The MPW configuration
2936 scripts */mpw-config.in support only a few targets, and only the
2937 mips-idt-ecoff target has been tested.
2941 GDB configuration now uses autoconf. This is not user-visible,
2942 but does simplify configuration and building.
2946 GDB now supports hpux10.
2948 *** Changes in GDB-4.14:
2950 * New native configurations
2952 x86 FreeBSD i[345]86-*-freebsd
2953 x86 NetBSD i[345]86-*-netbsd
2954 NS32k NetBSD ns32k-*-netbsd
2955 Sparc NetBSD sparc-*-netbsd
2959 A29K VxWorks a29k-*-vxworks
2960 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2961 CPU32 EST-300 emulator m68*-*-est*
2962 PowerPC ELF powerpc-*-elf
2965 * Alpha OSF/1 support for procfs
2967 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2968 possible to attach to running processes. As the mounting of the /proc
2969 filesystem is optional on the Alpha, GDB automatically determines
2970 the availability of /proc during startup. This can lead to problems
2971 if /proc is unmounted after GDB has been started.
2973 * Arguments to user-defined commands
2975 User commands may accept up to 10 arguments separated by whitespace.
2976 Arguments are accessed within the user command via $arg0..$arg9. A
2979 print $arg0 + $arg1 + $arg2
2981 To execute the command use:
2984 Defines the command "adder" which prints the sum of its three arguments.
2985 Note the arguments are text substitutions, so they may reference variables,
2986 use complex expressions, or even perform inferior function calls.
2988 * New `if' and `while' commands
2990 This makes it possible to write more sophisticated user-defined
2991 commands. Both commands take a single argument, which is the
2992 expression to evaluate, and must be followed by the commands to
2993 execute, one per line, if the expression is nonzero, the list being
2994 terminated by the word `end'. The `if' command list may include an
2995 `else' word, which causes the following commands to be executed only
2996 if the expression is zero.
2998 * Fortran source language mode
3000 GDB now includes partial support for Fortran 77. It will recognize
3001 Fortran programs and can evaluate a subset of Fortran expressions, but
3002 variables and functions may not be handled correctly. GDB will work
3003 with G77, but does not yet know much about symbols emitted by other
3006 * Better HPUX support
3008 Most debugging facilities now work on dynamic executables for HPPAs
3009 running hpux9 or later. You can attach to running dynamically linked
3010 processes, but by default the dynamic libraries will be read-only, so
3011 for instance you won't be able to put breakpoints in them. To change
3012 that behavior do the following before running the program:
3018 This will cause the libraries to be mapped private and read-write.
3019 To revert to the normal behavior, do this:
3025 You cannot set breakpoints or examine data in the library until after
3026 the library is loaded if the function/data symbols do not have
3029 GDB can now also read debug symbols produced by the HP C compiler on
3030 HPPAs (sorry, no C++, Fortran or 68k support).
3032 * Target byte order now dynamically selectable
3034 You can choose which byte order to use with a target system, via the
3035 commands "set endian big" and "set endian little", and you can see the
3036 current setting by using "show endian". You can also give the command
3037 "set endian auto", in which case GDB will use the byte order
3038 associated with the executable. Currently, only embedded MIPS
3039 configurations support dynamic selection of target byte order.
3041 * New DOS host serial code
3043 This version uses DPMI interrupts to handle buffered I/O, so you
3044 no longer need to run asynctsr when debugging boards connected to
3047 *** Changes in GDB-4.13:
3049 * New "complete" command
3051 This lists all the possible completions for the rest of the line, if it
3052 were to be given as a command itself. This is intended for use by emacs.
3054 * Trailing space optional in prompt
3056 "set prompt" no longer adds a space for you after the prompt you set. This
3057 allows you to set a prompt which ends in a space or one that does not.
3059 * Breakpoint hit counts
3061 "info break" now displays a count of the number of times the breakpoint
3062 has been hit. This is especially useful in conjunction with "ignore"; you
3063 can ignore a large number of breakpoint hits, look at the breakpoint info
3064 to see how many times the breakpoint was hit, then run again, ignoring one
3065 less than that number, and this will get you quickly to the last hit of
3068 * Ability to stop printing at NULL character
3070 "set print null-stop" will cause GDB to stop printing the characters of
3071 an array when the first NULL is encountered. This is useful when large
3072 arrays actually contain only short strings.
3074 * Shared library breakpoints
3076 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3077 breakpoints in shared libraries before the executable is run.
3079 * Hardware watchpoints
3081 There is a new hardware breakpoint for the watch command for sparclite
3082 targets. See gdb/sparclite/hw_breakpoint.note.
3084 Hardware watchpoints are also now supported under GNU/Linux.
3088 Annotations have been added. These are for use with graphical interfaces,
3089 and are still experimental. Currently only gdba.el uses these.
3091 * Improved Irix 5 support
3093 GDB now works properly with Irix 5.2.
3095 * Improved HPPA support
3097 GDB now works properly with the latest GCC and GAS.
3099 * New native configurations
3101 Sequent PTX4 i[34]86-sequent-ptx4
3102 HPPA running OSF/1 hppa*-*-osf*
3103 Atari TT running SVR4 m68*-*-sysv4*
3104 RS/6000 LynxOS rs6000-*-lynxos*
3108 OS/9000 i[34]86-*-os9k
3109 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3112 * Hitachi SH7000 and E7000-PC ICE support
3114 There is now support for communicating with the Hitachi E7000-PC ICE.
3115 This is available automatically when GDB is configured for the SH.
3119 As usual, a variety of small fixes and improvements, both generic
3120 and configuration-specific. See the ChangeLog for more detail.
3122 *** Changes in GDB-4.12:
3124 * Irix 5 is now supported
3128 GDB-4.12 on the HPPA has a number of changes which make it unable
3129 to debug the output from the currently released versions of GCC and
3130 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3131 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3132 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3135 *** Changes in GDB-4.11:
3137 * User visible changes:
3141 The "set remotedebug" option is now consistent between the mips remote
3142 target, remote targets using the gdb-specific protocol, UDI (AMD's
3143 debug protocol for the 29k) and the 88k bug monitor. It is now an
3144 integer specifying a debug level (normally 0 or 1, but 2 means more
3145 debugging info for the mips target).
3147 * DEC Alpha native support
3149 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3150 debug info, but GDB works fairly well with the DEC compiler and should
3151 work with a future GCC release. See the README file for a few
3152 Alpha-specific notes.
3154 * Preliminary thread implementation
3156 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3158 * LynxOS native and target support for 386
3160 This release has been hosted on LynxOS 2.2, and also can be configured
3161 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3164 * Improvements in C++ mangling/demangling.
3166 This release has much better g++ debugging, specifically in name
3167 mangling/demangling, virtual function calls, print virtual table,
3168 call methods, ...etc.
3170 *** Changes in GDB-4.10:
3172 * User visible changes:
3174 Remote debugging using the GDB-specific (`target remote') protocol now
3175 supports the `load' command. This is only useful if you have some
3176 other way of getting the stub to the target system, and you can put it
3177 somewhere in memory where it won't get clobbered by the download.
3179 Filename completion now works.
3181 When run under emacs mode, the "info line" command now causes the
3182 arrow to point to the line specified. Also, "info line" prints
3183 addresses in symbolic form (as well as hex).
3185 All vxworks based targets now support a user settable option, called
3186 vxworks-timeout. This option represents the number of seconds gdb
3187 should wait for responses to rpc's. You might want to use this if
3188 your vxworks target is, perhaps, a slow software simulator or happens
3189 to be on the far side of a thin network line.
3193 This release contains support for using a DEC alpha as a GDB host for
3194 cross debugging. Native alpha debugging is not supported yet.
3197 *** Changes in GDB-4.9:
3201 This is the first GDB release which is accompanied by a matching testsuite.
3202 The testsuite requires installation of dejagnu, which should be available
3203 via ftp from most sites that carry GNU software.
3207 'Cfront' style demangling has had its name changed to 'ARM' style, to
3208 emphasize that it was written from the specifications in the C++ Annotated
3209 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3210 disclaimers, it still generated too much confusion with users attempting to
3211 use gdb with AT&T cfront.
3215 GDB now uses a standard remote interface to a simulator library.
3216 So far, the library contains simulators for the Zilog Z8001/2, the
3217 Hitachi H8/300, H8/500 and Super-H.
3219 * New targets supported
3221 H8/300 simulator h8300-hitachi-hms or h8300hms
3222 H8/500 simulator h8500-hitachi-hms or h8500hms
3223 SH simulator sh-hitachi-hms or sh
3224 Z8000 simulator z8k-zilog-none or z8ksim
3225 IDT MIPS board over serial line mips-idt-ecoff
3227 Cross-debugging to GO32 targets is supported. It requires a custom
3228 version of the i386-stub.c module which is integrated with the
3229 GO32 memory extender.
3231 * New remote protocols
3233 MIPS remote debugging protocol.
3235 * New source languages supported
3237 This version includes preliminary support for Chill, a Pascal like language
3238 used by telecommunications companies. Chill support is also being integrated
3239 into the GNU compiler, but we don't know when it will be publically available.
3242 *** Changes in GDB-4.8:
3244 * HP Precision Architecture supported
3246 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3247 version of this support was available as a set of patches from the
3248 University of Utah. GDB does not support debugging of programs
3249 compiled with the HP compiler, because HP will not document their file
3250 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3251 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3253 Many problems in the preliminary version have been fixed.
3255 * Faster and better demangling
3257 We have improved template demangling and fixed numerous bugs in the GNU style
3258 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3259 character types (wchar_t) are now supported. Demangling of each symbol is now
3260 only done once, and is cached when the symbol table for a file is read in.
3261 This results in a small increase in memory usage for C programs, a moderate
3262 increase in memory usage for C++ programs, and a fantastic speedup in
3265 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3266 from the specifications in the Annotated Reference Manual, which AT&T's
3267 compiler does not actually implement.
3269 * G++ multiple inheritance compiler problem
3271 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3272 inheritance lattices was reworked to properly discover ambiguities. We
3273 recently found an example which causes this new algorithm to fail in a
3274 very subtle way, producing bad debug information for those classes.
3275 The file 'gcc.patch' (in this directory) can be applied to gcc to
3276 circumvent the problem. A future GCC release will contain a complete
3279 The previous G++ debug info problem (mentioned below for the gdb-4.7
3280 release) is fixed in gcc version 2.3.2.
3282 * Improved configure script
3284 The `configure' script will now attempt to guess your system type if
3285 you don't supply a host system type. The old scheme of supplying a
3286 host system triplet is preferable over using this. All the magic is
3287 done in the new `config.guess' script. Examine it for details.
3289 We have also brought our configure script much more in line with the FSF's
3290 version. It now supports the --with-xxx options. In particular,
3291 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3292 The resulting GDB will not be able to read arbitrary object file formats --
3293 only the format ``expected'' to be used on the configured target system.
3294 We hope to make this the default in a future release.
3296 * Documentation improvements
3298 There's new internal documentation on how to modify GDB, and how to
3299 produce clean changes to the code. We implore people to read it
3300 before submitting changes.
3302 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3303 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3304 `info' files are also provided. To build `info' files from scratch,
3305 you will need the latest `makeinfo' release, which will be available in
3306 a future texinfo-X.Y release.
3308 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3309 We're not sure exactly which versions have this problem, but it has
3310 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3311 or better. If that isn't possible, there is a patch in
3312 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3313 around this problem.
3317 GDB now supports array constants that can be used in expressions typed in by
3318 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3319 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3322 The new directory `gdb/sparclite' contains a program that demonstrates
3323 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3325 * New native hosts supported
3327 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3328 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3330 * New targets supported
3332 AMD 29k family via UDI a29k-amd-udi or udi29k
3334 * New file formats supported
3336 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3337 HPUX core files, and SCO 3.2v2 core files.
3341 Attaching to processes now works again; thanks for the many bug reports.
3343 We have also stomped on a bunch of core dumps caused by
3344 printf_filtered("%s") problems.
3346 We eliminated a copyright problem on the rpc and ptrace header files
3347 for VxWorks, which was discovered at the last minute during the 4.7
3348 release. You should now be able to build a VxWorks GDB.
3350 You can now interrupt gdb while an attached process is running. This
3351 will cause the attached process to stop, and give control back to GDB.
3353 We fixed problems caused by using too many file descriptors
3354 for reading symbols from object files and libraries. This was
3355 especially a problem for programs that used many (~100) shared
3358 The `step' command now only enters a subroutine if there is line number
3359 information for the subroutine. Otherwise it acts like the `next'
3360 command. Previously, `step' would enter subroutines if there was
3361 any debugging information about the routine. This avoids problems
3362 when using `cc -g1' on MIPS machines.
3364 * Internal improvements
3366 GDB's internal interfaces have been improved to make it easier to support
3367 debugging of multiple languages in the future.
3369 GDB now uses a common structure for symbol information internally.
3370 Minimal symbols (derived from linkage symbols in object files), partial
3371 symbols (from a quick scan of debug information), and full symbols
3372 contain a common subset of information, making it easier to write
3373 shared code that handles any of them.
3375 * New command line options
3377 We now accept --silent as an alias for --quiet.
3381 The memory-mapped-malloc library is now licensed under the GNU Library
3382 General Public License.
3384 *** Changes in GDB-4.7:
3386 * Host/native/target split
3388 GDB has had some major internal surgery to untangle the support for
3389 hosts and remote targets. Now, when you configure GDB for a remote
3390 target, it will no longer load in all of the support for debugging
3391 local programs on the host. When fully completed and tested, this will
3392 ensure that arbitrary host/target combinations are possible.
3394 The primary conceptual shift is to separate the non-portable code in
3395 GDB into three categories. Host specific code is required any time GDB
3396 is compiled on that host, regardless of the target. Target specific
3397 code relates to the peculiarities of the target, but can be compiled on
3398 any host. Native specific code is everything else: it can only be
3399 built when the host and target are the same system. Child process
3400 handling and core file support are two common `native' examples.
3402 GDB's use of /proc for controlling Unix child processes is now cleaner.
3403 It has been split out into a single module under the `target_ops' vector,
3404 plus two native-dependent functions for each system that uses /proc.
3406 * New hosts supported
3408 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3409 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3410 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3412 * New targets supported
3414 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3415 68030 and CPU32 m68030-*-*, m68332-*-*
3417 * New native hosts supported
3419 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3420 (386bsd is not well tested yet)
3421 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3423 * New file formats supported
3425 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3426 supports reading of `a.out.adobe' object files, which are an a.out
3427 format extended with minimal information about multiple sections.
3431 `show copying' is the same as the old `info copying'.
3432 `show warranty' is the same as `info warrantee'.
3433 These were renamed for consistency. The old commands continue to work.
3435 `info handle' is a new alias for `info signals'.
3437 You can now define pre-command hooks, which attach arbitrary command
3438 scripts to any command. The commands in the hook will be executed
3439 prior to the user's command. You can also create a hook which will be
3440 executed whenever the program stops. See gdb.texinfo.
3444 We now deal with Cfront style name mangling, and can even extract type
3445 info from mangled symbols. GDB can automatically figure out which
3446 symbol mangling style your C++ compiler uses.
3448 Calling of methods and virtual functions has been improved as well.
3452 The crash that occured when debugging Sun Ansi-C compiled binaries is
3453 fixed. This was due to mishandling of the extra N_SO stabs output
3456 We also finally got Ultrix 4.2 running in house, and fixed core file
3457 support, with help from a dozen people on the net.
3459 John M. Farrell discovered that the reason that single-stepping was so
3460 slow on all of the Mips based platforms (primarily SGI and DEC) was
3461 that we were trying to demangle and lookup a symbol used for internal
3462 purposes on every instruction that was being stepped through. Changing
3463 the name of that symbol so that it couldn't be mistaken for a C++
3464 mangled symbol sped things up a great deal.
3466 Rich Pixley sped up symbol lookups in general by getting much smarter
3467 about when C++ symbol mangling is necessary. This should make symbol
3468 completion (TAB on the command line) much faster. It's not as fast as
3469 we'd like, but it's significantly faster than gdb-4.6.
3473 A new user controllable variable 'call_scratch_address' can
3474 specify the location of a scratch area to be used when GDB
3475 calls a function in the target. This is necessary because the
3476 usual method of putting the scratch area on the stack does not work
3477 in systems that have separate instruction and data spaces.
3479 We integrated changes to support the 29k UDI (Universal Debugger
3480 Interface), but discovered at the last minute that we didn't have all
3481 of the appropriate copyright paperwork. We are working with AMD to
3482 resolve this, and hope to have it available soon.
3486 We have sped up the remote serial line protocol, especially for targets
3487 with lots of registers. It now supports a new `expedited status' ('T')
3488 message which can be used in place of the existing 'S' status message.
3489 This allows the remote stub to send only the registers that GDB
3490 needs to make a quick decision about single-stepping or conditional
3491 breakpoints, eliminating the need to fetch the entire register set for
3492 each instruction being stepped through.
3494 The GDB remote serial protocol now implements a write-through cache for
3495 registers, only re-reading the registers if the target has run.
3497 There is also a new remote serial stub for SPARC processors. You can
3498 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3499 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3500 processor with a serial port.
3504 Configure.in files have become much easier to read and modify. A new
3505 `table driven' format makes it more obvious what configurations are
3506 supported, and what files each one uses.
3510 There is a new opcodes library which will eventually contain all of the
3511 disassembly routines and opcode tables. At present, it only contains
3512 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3513 disassembler (binutils/objdump) to share these routines.
3515 The libiberty library is now copylefted under the GNU Library General
3516 Public License. This allows more liberal use, and was done so libg++
3517 can use it. This makes no difference to GDB, since the Library License
3518 grants all the rights from the General Public License.
3522 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3523 reference to the stabs symbol info used by the debugger. It is (as far
3524 as we know) the only published document on this fascinating topic. We
3525 encourage you to read it, compare it to the stabs information on your
3526 system, and send improvements on the document in general (to
3527 bug-gdb@prep.ai.mit.edu).
3529 And, of course, many bugs have been fixed.
3532 *** Changes in GDB-4.6:
3534 * Better support for C++ function names
3536 GDB now accepts as input the "demangled form" of C++ overloaded function
3537 names and member function names, and can do command completion on such names
3538 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3539 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3540 Make use of command completion, it is your friend.
3542 GDB also now accepts a variety of C++ mangled symbol formats. They are
3543 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3544 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3545 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3546 for the list of formats.
3548 * G++ symbol mangling problem
3550 Recent versions of gcc have a bug in how they emit debugging information for
3551 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3552 directory) can be applied to gcc to fix the problem. Alternatively, if you
3553 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3554 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3555 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3558 * New 'maintenance' command
3560 All of the commands related to hacking GDB internals have been moved out of
3561 the main command set, and now live behind the 'maintenance' command. This
3562 can also be abbreviated as 'mt'. The following changes were made:
3564 dump-me -> maintenance dump-me
3565 info all-breakpoints -> maintenance info breakpoints
3566 printmsyms -> maintenance print msyms
3567 printobjfiles -> maintenance print objfiles
3568 printpsyms -> maintenance print psymbols
3569 printsyms -> maintenance print symbols
3571 The following commands are new:
3573 maintenance demangle Call internal GDB demangler routine to
3574 demangle a C++ link name and prints the result.
3575 maintenance print type Print a type chain for a given symbol
3577 * Change to .gdbinit file processing
3579 We now read the $HOME/.gdbinit file before processing the argv arguments
3580 (e.g. reading symbol files or core files). This allows global parameters to
3581 be set, which will apply during the symbol reading. The ./.gdbinit is still
3582 read after argv processing.
3584 * New hosts supported
3586 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3588 GNU/Linux support i386-unknown-linux or linux
3590 We are also including code to support the HP/PA running BSD and HPUX. This
3591 is almost guaranteed not to work, as we didn't have time to test or build it
3592 for this release. We are including it so that the more adventurous (or
3593 masochistic) of you can play with it. We also had major problems with the
3594 fact that the compiler that we got from HP doesn't support the -g option.
3597 * New targets supported
3599 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3601 * More smarts about finding #include files
3603 GDB now remembers the compilation directory for all include files, and for
3604 all files from which C is generated (like yacc and lex sources). This
3605 greatly improves GDB's ability to find yacc/lex sources, and include files,
3606 especially if you are debugging your program from a directory different from
3607 the one that contains your sources.
3609 We also fixed a bug which caused difficulty with listing and setting
3610 breakpoints in include files which contain C code. (In the past, you had to
3611 try twice in order to list an include file that you hadn't looked at before.)
3613 * Interesting infernals change
3615 GDB now deals with arbitrary numbers of sections, where the symbols for each
3616 section must be relocated relative to that section's landing place in the
3617 target's address space. This work was needed to support ELF with embedded
3618 stabs used by Solaris-2.0.
3620 * Bug fixes (of course!)
3622 There have been loads of fixes for the following things:
3623 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3624 i960, stabs, DOS(GO32), procfs, etc...
3626 See the ChangeLog for details.
3628 *** Changes in GDB-4.5:
3630 * New machines supported (host and target)
3632 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3634 SGI Irix-4.x mips-sgi-irix4 or iris4
3636 * New malloc package
3638 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3639 Mmalloc is capable of handling mutiple heaps of memory. It is also
3640 capable of saving a heap to a file, and then mapping it back in later.
3641 This can be used to greatly speedup the startup of GDB by using a
3642 pre-parsed symbol table which lives in a mmalloc managed heap. For
3643 more details, please read mmalloc/mmalloc.texi.
3647 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3648 'help info proc' for details.
3650 * MIPS ecoff symbol table format
3652 The code that reads MIPS symbol table format is now supported on all hosts.
3653 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3656 * File name changes for MS-DOS
3658 Many files in the config directories have been renamed to make it easier to
3659 support GDB on MS-DOSe systems (which have very restrictive file name
3660 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3661 environment) is close to working but has some remaining problems. Note
3662 that debugging of DOS programs is not supported, due to limitations
3663 in the ``operating system'', but it can be used to host cross-debugging.
3665 * Cross byte order fixes
3667 Many fixes have been made to support cross debugging of Sparc and MIPS
3668 targets from hosts whose byte order differs.
3670 * New -mapped and -readnow options
3672 If memory-mapped files are available on your system through the 'mmap'
3673 system call, you can use the -mapped option on the `file' or
3674 `symbol-file' commands to cause GDB to write the symbols from your
3675 program into a reusable file. If the program you are debugging is
3676 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3677 Future GDB debugging sessions will notice the presence of this file,
3678 and will quickly map in symbol information from it, rather than reading
3679 the symbol table from the executable program. Using the '-mapped'
3680 option in a GDB `file' or `symbol-file' command has the same effect as
3681 starting GDB with the '-mapped' command-line option.
3683 You can cause GDB to read the entire symbol table immediately by using
3684 the '-readnow' option with any of the commands that load symbol table
3685 information (or on the GDB command line). This makes the command
3686 slower, but makes future operations faster.
3688 The -mapped and -readnow options are typically combined in order to
3689 build a `fred.syms' file that contains complete symbol information.
3690 A simple GDB invocation to do nothing but build a `.syms' file for future
3693 gdb -batch -nx -mapped -readnow programname
3695 The `.syms' file is specific to the host machine on which GDB is run.
3696 It holds an exact image of GDB's internal symbol table. It cannot be
3697 shared across multiple host platforms.
3699 * longjmp() handling
3701 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3702 siglongjmp() without losing control. This feature has not yet been ported to
3703 all systems. It currently works on many 386 platforms, all MIPS-based
3704 platforms (SGI, DECstation, etc), and Sun3/4.
3708 Preliminary work has been put in to support the new Solaris OS from Sun. At
3709 this time, it can control and debug processes, but it is not capable of
3714 As always, many many bug fixes. The major areas were with g++, and mipsread.
3715 People using the MIPS-based platforms should experience fewer mysterious
3716 crashes and trashed symbol tables.
3718 *** Changes in GDB-4.4:
3720 * New machines supported (host and target)
3722 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3724 BSD Reno on Vax vax-dec-bsd
3725 Ultrix on Vax vax-dec-ultrix
3727 * New machines supported (target)
3729 AMD 29000 embedded, using EBMON a29k-none-none
3733 GDB continues to improve its handling of C++. `References' work better.
3734 The demangler has also been improved, and now deals with symbols mangled as
3735 per the Annotated C++ Reference Guide.
3737 GDB also now handles `stabs' symbol information embedded in MIPS
3738 `ecoff' symbol tables. Since the ecoff format was not easily
3739 extensible to handle new languages such as C++, this appeared to be a
3740 good way to put C++ debugging info into MIPS binaries. This option
3741 will be supported in the GNU C compiler, version 2, when it is
3744 * New features for SVR4
3746 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3747 shared libraries. Debugging dynamically linked programs should present
3748 only minor differences from debugging statically linked programs.
3750 The `info proc' command will print out information about any process
3751 on an SVR4 system (including the one you are debugging). At the moment,
3752 it prints the address mappings of the process.
3754 If you bring up GDB on another SVR4 system, please send mail to
3755 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3757 * Better dynamic linking support in SunOS
3759 Reading symbols from shared libraries which contain debugging symbols
3760 now works properly. However, there remain issues such as automatic
3761 skipping of `transfer vector' code during function calls, which
3762 make it harder to debug code in a shared library, than to debug the
3763 same code linked statically.
3767 GDB is now using the latest `getopt' routines from the FSF. This
3768 version accepts the -- prefix for options with long names. GDB will
3769 continue to accept the old forms (-option and +option) as well.
3770 Various single letter abbreviations for options have been explicity
3771 added to the option table so that they won't get overshadowed in the
3772 future by other options that begin with the same letter.
3776 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3777 Many assorted bugs have been handled. Many more remain to be handled.
3778 See the various ChangeLog files (primarily in gdb and bfd) for details.
3781 *** Changes in GDB-4.3:
3783 * New machines supported (host and target)
3785 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3786 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3787 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3789 * Almost SCO Unix support
3791 We had hoped to support:
3792 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3793 (except for core file support), but we discovered very late in the release
3794 that it has problems with process groups that render gdb unusable. Sorry
3795 about that. I encourage people to fix it and post the fixes.
3797 * Preliminary ELF and DWARF support
3799 GDB can read ELF object files on System V Release 4, and can handle
3800 debugging records for C, in DWARF format, in ELF files. This support
3801 is preliminary. If you bring up GDB on another SVR4 system, please
3802 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3807 GDB now uses the latest `readline' library. One user-visible change
3808 is that two tabs will list possible command completions, which previously
3809 required typing M-? (meta-question mark, or ESC ?).
3813 The `stepi' bug that many of you noticed has been squashed.
3814 Many bugs in C++ have been handled. Many more remain to be handled.
3815 See the various ChangeLog files (primarily in gdb and bfd) for details.
3817 * State of the MIPS world (in case you wondered):
3819 GDB can understand the symbol tables emitted by the compilers
3820 supplied by most vendors of MIPS-based machines, including DEC. These
3821 symbol tables are in a format that essentially nobody else uses.
3823 Some versions of gcc come with an assembler post-processor called
3824 mips-tfile. This program is required if you want to do source-level
3825 debugging of gcc-compiled programs. I believe FSF does not ship
3826 mips-tfile with gcc version 1, but it will eventually come with gcc
3829 Debugging of g++ output remains a problem. g++ version 1.xx does not
3830 really support it at all. (If you're lucky, you should be able to get
3831 line numbers and stack traces to work, but no parameters or local
3832 variables.) With some work it should be possible to improve the
3835 When gcc version 2 is released, you will have somewhat better luck.
3836 However, even then you will get confusing results for inheritance and
3839 We will eventually provide full debugging of g++ output on
3840 DECstations. This will probably involve some kind of stabs-in-ecoff
3841 encapulation, but the details have not been worked out yet.
3844 *** Changes in GDB-4.2:
3846 * Improved configuration
3848 Only one copy of `configure' exists now, and it is not self-modifying.
3849 Porting BFD is simpler.
3853 The `step' and `next' commands now only stop at the first instruction
3854 of a source line. This prevents the multiple stops that used to occur
3855 in switch statements, for-loops, etc. `Step' continues to stop if a
3856 function that has debugging information is called within the line.
3860 Lots of small bugs fixed. More remain.
3862 * New host supported (not target)
3864 Intel 386 PC clone running Mach i386-none-mach
3867 *** Changes in GDB-4.1:
3869 * Multiple source language support
3871 GDB now has internal scaffolding to handle several source languages.
3872 It determines the type of each source file from its filename extension,
3873 and will switch expression parsing and number formatting to match the
3874 language of the function in the currently selected stack frame.
3875 You can also specifically set the language to be used, with
3876 `set language c' or `set language modula-2'.
3880 GDB now has preliminary support for the GNU Modula-2 compiler,
3881 currently under development at the State University of New York at
3882 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3883 continue through the fall of 1991 and into 1992.
3885 Other Modula-2 compilers are currently not supported, and attempting to
3886 debug programs compiled with them will likely result in an error as the
3887 symbol table is read. Feel free to work on it, though!
3889 There are hooks in GDB for strict type checking and range checking,
3890 in the `Modula-2 philosophy', but they do not currently work.
3894 GDB can now write to executable and core files (e.g. patch
3895 a variable's value). You must turn this switch on, specify
3896 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3897 by assigning a new value to a variable. Modifications take
3900 * Automatic SunOS shared library reading
3902 When you run your program, GDB automatically determines where its
3903 shared libraries (if any) have been loaded, and reads their symbols.
3904 The `share' command is no longer needed. This also works when
3905 examining core files.
3909 You can specify the number of lines that the `list' command shows.
3912 * New machines supported (host and target)
3914 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3915 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3916 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3918 * New hosts supported (not targets)
3920 IBM RT/PC: romp-ibm-aix or rtpc
3922 * New targets supported (not hosts)
3924 AMD 29000 embedded with COFF a29k-none-coff
3925 AMD 29000 embedded with a.out a29k-none-aout
3926 Ultracomputer remote kernel debug a29k-nyu-kern
3928 * New remote interfaces
3934 *** Changes in GDB-4.0:
3938 Wide output is wrapped at good places to make the output more readable.
3940 Gdb now supports cross-debugging from a host machine of one type to a
3941 target machine of another type. Communication with the target system
3942 is over serial lines. The ``target'' command handles connecting to the
3943 remote system; the ``load'' command will download a program into the
3944 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3945 also supports debugging of realtime processes running under VxWorks,
3946 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3947 stub on the target system.
3949 New CPUs supported include the AMD 29000 and Intel 960.
3951 GDB now reads object files and symbol tables via a ``binary file''
3952 library, which allows a single copy of GDB to debug programs of multiple
3953 object file types such as a.out and coff.
3955 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3956 refcard.dvi and refcard.ps are available to format it).
3959 * Control-Variable user interface simplified
3961 All variables that control the operation of the debugger can be set
3962 by the ``set'' command, and displayed by the ``show'' command.
3964 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3965 ``Show prompt'' produces the response:
3966 Gdb's prompt is new-gdb=>.
3968 What follows are the NEW set commands. The command ``help set'' will
3969 print a complete list of old and new set commands. ``help set FOO''
3970 will give a longer description of the variable FOO. ``show'' will show
3971 all of the variable descriptions and their current settings.
3973 confirm on/off: Enables warning questions for operations that are
3974 hard to recover from, e.g. rerunning the program while
3975 it is already running. Default is ON.
3977 editing on/off: Enables EMACS style command line editing
3978 of input. Previous lines can be recalled with
3979 control-P, the current line can be edited with control-B,
3980 you can search for commands with control-R, etc.
3983 history filename NAME: NAME is where the gdb command history
3984 will be stored. The default is .gdb_history,
3985 or the value of the environment variable
3988 history size N: The size, in commands, of the command history. The
3989 default is 256, or the value of the environment variable
3992 history save on/off: If this value is set to ON, the history file will
3993 be saved after exiting gdb. If set to OFF, the
3994 file will not be saved. The default is OFF.
3996 history expansion on/off: If this value is set to ON, then csh-like
3997 history expansion will be performed on
3998 command line input. The default is OFF.
4000 radix N: Sets the default radix for input and output. It can be set
4001 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4002 in the current radix, so "set radix 10" is always a no-op.
4004 height N: This integer value is the number of lines on a page. Default
4005 is 24, the current `stty rows'' setting, or the ``li#''
4006 setting from the termcap entry matching the environment
4009 width N: This integer value is the number of characters on a line.
4010 Default is 80, the current `stty cols'' setting, or the ``co#''
4011 setting from the termcap entry matching the environment
4014 Note: ``set screensize'' is obsolete. Use ``set height'' and
4015 ``set width'' instead.
4017 print address on/off: Print memory addresses in various command displays,
4018 such as stack traces and structure values. Gdb looks
4019 more ``symbolic'' if you turn this off; it looks more
4020 ``machine level'' with it on. Default is ON.
4022 print array on/off: Prettyprint arrays. New convenient format! Default
4025 print demangle on/off: Print C++ symbols in "source" form if on,
4028 print asm-demangle on/off: Same, for assembler level printouts
4031 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4034 * Support for Epoch Environment.
4036 The epoch environment is a version of Emacs v18 with windowing. One
4037 new command, ``inspect'', is identical to ``print'', except that if you
4038 are running in the epoch environment, the value is printed in its own
4042 * Support for Shared Libraries
4044 GDB can now debug programs and core files that use SunOS shared libraries.
4045 Symbols from a shared library cannot be referenced
4046 before the shared library has been linked with the program (this
4047 happens after you type ``run'' and before the function main() is entered).
4048 At any time after this linking (including when examining core files
4049 from dynamically linked programs), gdb reads the symbols from each
4050 shared library when you type the ``sharedlibrary'' command.
4051 It can be abbreviated ``share''.
4053 sharedlibrary REGEXP: Load shared object library symbols for files
4054 matching a unix regular expression. No argument
4055 indicates to load symbols for all shared libraries.
4057 info sharedlibrary: Status of loaded shared libraries.
4062 A watchpoint stops execution of a program whenever the value of an
4063 expression changes. Checking for this slows down execution
4064 tremendously whenever you are in the scope of the expression, but is
4065 quite useful for catching tough ``bit-spreader'' or pointer misuse
4066 problems. Some machines such as the 386 have hardware for doing this
4067 more quickly, and future versions of gdb will use this hardware.
4069 watch EXP: Set a watchpoint (breakpoint) for an expression.
4071 info watchpoints: Information about your watchpoints.
4073 delete N: Deletes watchpoint number N (same as breakpoints).
4074 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4075 enable N: Re-enables watchpoint number N (same as breakpoints).
4078 * C++ multiple inheritance
4080 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4083 * C++ exception handling
4085 Gdb now supports limited C++ exception handling. Besides the existing
4086 ability to breakpoint on an exception handler, gdb can breakpoint on
4087 the raising of an exception (before the stack is peeled back to the
4090 catch FOO: If there is a FOO exception handler in the dynamic scope,
4091 set a breakpoint to catch exceptions which may be raised there.
4092 Multiple exceptions (``catch foo bar baz'') may be caught.
4094 info catch: Lists all exceptions which may be caught in the
4095 current stack frame.
4098 * Minor command changes
4100 The command ``call func (arg, arg, ...)'' now acts like the print
4101 command, except it does not print or save a value if the function's result
4102 is void. This is similar to dbx usage.
4104 The ``up'' and ``down'' commands now always print the frame they end up
4105 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4106 frames without printing.
4108 * New directory command
4110 'dir' now adds directories to the FRONT of the source search path.
4111 The path starts off empty. Source files that contain debug information
4112 about the directory in which they were compiled can be found even
4113 with an empty path; Sun CC and GCC include this information. If GDB can't
4114 find your source file in the current directory, type "dir .".
4116 * Configuring GDB for compilation
4118 For normal use, type ``./configure host''. See README or gdb.texinfo
4121 GDB now handles cross debugging. If you are remotely debugging between
4122 two different machines, type ``./configure host -target=targ''.
4123 Host is the machine where GDB will run; targ is the machine
4124 where the program that you are debugging will run.