1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.1
6 * The --batch flag now disables pagination and queries.
8 * X86 general purpose registers
10 GDB now supports reading/writing byte, word and double-word x86
11 general purpose registers directly. This means you can use, say,
12 $ah or $ax to refer, respectively, to the byte register AH and
13 16-bit word register AX that are actually portions of the 32-bit
14 register EAX or 64-bit register RAX.
16 * The `commands' command now accepts a range of breakpoints to modify.
17 A plain `commands' following an `rbreak' will affect all the
18 breakpoints set by `rbreak'.
22 ** The GDB Python API now has access to symbols, symbol tables, and
25 ** New methods gdb.target_charset and gdb.target_wide_charset.
27 * Tracepoint actions were unified with breakpoint commands. In particular,
28 there are no longer differences in "info break" output for breakpoints and
29 tracepoints and the "commands" command can be used for both tracepoints and
34 ARM Symbian arm*-*-symbianelf*
36 *** Changes in GDB 7.1
42 GDB now supports importing of namespaces in C++. This enables the
43 user to inspect variables from imported namespaces. Support for
44 namepace aliasing has also been added. So, if a namespace is
45 aliased in the current scope (e.g. namepace C=A; ) the user can
46 print variables using the alias (e.g. (gdb) print C::x).
50 All known bugs relating to the printing of virtual base class were
51 fixed. It is now possible to call overloaded static methods using a
56 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
57 and reinterpret_cast<> are now handled by the C++ expression parser.
61 Xilinx MicroBlaze microblaze-*-*
66 Xilinx MicroBlaze microblaze
69 * Multi-program debugging.
71 GDB now has support for multi-program (a.k.a. multi-executable or
72 multi-exec) debugging. This allows for debugging multiple inferiors
73 simultaneously each running a different program under the same GDB
74 session. See "Debugging Multiple Inferiors and Programs" in the
75 manual for more information. This implied some user visible changes
76 in the multi-inferior support. For example, "info inferiors" now
77 lists inferiors that are not running yet or that have exited
78 already. See also "New commands" and "New options" below.
80 * New tracing features
82 GDB's tracepoint facility now includes several new features:
84 ** Trace state variables
86 GDB tracepoints now include support for trace state variables, which
87 are variables managed by the target agent during a tracing
88 experiment. They are useful for tracepoints that trigger each
89 other, so for instance one tracepoint can count hits in a variable,
90 and then a second tracepoint has a condition that is true when the
91 count reaches a particular value. Trace state variables share the
92 $-syntax of GDB convenience variables, and can appear in both
93 tracepoint actions and condition expressions. Use the "tvariable"
94 command to create, and "info tvariables" to view; see "Trace State
95 Variables" in the manual for more detail.
99 GDB now includes an option for defining fast tracepoints, which
100 targets may implement more efficiently, such as by installing a jump
101 into the target agent rather than a trap instruction. The resulting
102 speedup can be by two orders of magnitude or more, although the
103 tradeoff is that some program locations on some target architectures
104 might not allow fast tracepoint installation, for instance if the
105 instruction to be replaced is shorter than the jump. To request a
106 fast tracepoint, use the "ftrace" command, with syntax identical to
107 the regular trace command.
109 ** Disconnected tracing
111 It is now possible to detach GDB from the target while it is running
112 a trace experiment, then reconnect later to see how the experiment
113 is going. In addition, a new variable disconnected-tracing lets you
114 tell the target agent whether to continue running a trace if the
115 connection is lost unexpectedly.
119 GDB now has the ability to save the trace buffer into a file, and
120 then use that file as a target, similarly to you can do with
121 corefiles. You can select trace frames, print data that was
122 collected in them, and use tstatus to display the state of the
123 tracing run at the moment that it was saved. To create a trace
124 file, use "tsave <filename>", and to use it, do "target tfile
127 ** Circular trace buffer
129 You can ask the target agent to handle the trace buffer as a
130 circular buffer, discarding the oldest trace frames to make room for
131 newer ones, by setting circular-trace-buffer to on. This feature may
132 not be available for all target agents.
137 The disassemble command, when invoked with two arguments, now requires
138 the arguments to be comma-separated.
141 The info variables command now displays variable definitions. Files
142 which only declare a variable are not shown.
145 The source command is now capable of sourcing Python scripts.
146 This feature is dependent on the debugger being build with Python
149 Related to this enhancement is also the introduction of a new command
150 "set script-extension" (see below).
152 * New commands (for set/show, see "New options" below)
154 record save [<FILENAME>]
155 Save a file (in core file format) containing the process record
156 execution log for replay debugging at a later time.
158 record restore <FILENAME>
159 Restore the process record execution log that was saved at an
160 earlier time, for replay debugging.
162 add-inferior [-copies <N>] [-exec <FILENAME>]
165 clone-inferior [-copies <N>] [ID]
166 Make a new inferior ready to execute the same program another
172 maint info program-spaces
173 List the program spaces loaded into GDB.
175 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
176 show remote interrupt-sequence
177 Allow the user to select one of ^C, a BREAK signal or BREAK-g
178 as the sequence to the remote target in order to interrupt the execution.
179 Ctrl-C is a default. Some system prefers BREAK which is high level of
180 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
181 Magic SysRq g. It is BREAK signal and character 'g'.
183 set remote interrupt-on-connect [on | off]
184 show remote interrupt-on-connect
185 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
186 remote target when gdb connects to it. This is needed when you debug
189 set remotebreak [on | off]
191 Deprecated. Use "set/show remote interrupt-sequence" instead.
193 tvariable $NAME [ = EXP ]
194 Create or modify a trace state variable.
197 List trace state variables and their values.
199 delete tvariable $NAME ...
200 Delete one or more trace state variables.
203 Evaluate the given expressions without collecting anything into the
204 trace buffer. (Valid in tracepoint actions only.)
206 ftrace FN / FILE:LINE / *ADDR
207 Define a fast tracepoint at the given function, line, or address.
209 * New expression syntax
211 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
212 GDB now parses 0b101010 identically with 42.
216 set follow-exec-mode new|same
217 show follow-exec-mode
218 Control whether GDB reuses the same inferior across an exec call or
219 creates a new one. This is useful to be able to restart the old
220 executable after the inferior having done an exec call.
222 set default-collect EXPR, ...
224 Define a list of expressions to be collected at each tracepoint.
225 This is a useful way to ensure essential items are not overlooked,
226 such as registers or a critical global variable.
228 set disconnected-tracing
229 show disconnected-tracing
230 If set to 1, the target is instructed to continue tracing if it
231 loses its connection to GDB. If 0, the target is to stop tracing
234 set circular-trace-buffer
235 show circular-trace-buffer
236 If set to on, the target is instructed to use a circular trace buffer
237 and discard the oldest trace frames instead of stopping the trace due
238 to a full trace buffer. If set to off, the trace stops when the buffer
239 fills up. Some targets may not support this.
241 set script-extension off|soft|strict
242 show script-extension
243 If set to "off", the debugger does not perform any script language
244 recognition, and all sourced files are assumed to be GDB scripts.
245 If set to "soft" (the default), files are sourced according to
246 filename extension, falling back to GDB scripts if the first
248 If set to "strict", files are sourced according to filename extension.
250 set ada trust-PAD-over-XVS on|off
251 show ada trust-PAD-over-XVS
252 If off, activate a workaround against a bug in the debugging information
253 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
254 the GCC sources for more information about the GNAT encoding and
255 PAD types in particular). It is always safe to set this option to
256 off, but this introduces a slight performance penalty. The default
259 * Python API Improvements
261 ** GDB provides the new class gdb.LazyString. This is useful in
262 some pretty-printing cases. The new method gdb.Value.lazy_string
263 provides a simple way to create objects of this type.
265 ** The fields returned by gdb.Type.fields now have an
266 `is_base_class' attribute.
268 ** The new method gdb.Type.range returns the range of an array type.
270 ** The new method gdb.parse_and_eval can be used to parse and
271 evaluate an expression.
276 Define a trace state variable.
279 Get the current value of a trace state variable.
282 Set desired tracing behavior upon disconnection.
285 Set the trace buffer to be linear or circular.
288 Get data about the tracepoints currently in use.
292 Process record now works correctly with hardware watchpoints.
294 Multiple bug fixes have been made to the mips-irix port, making it
295 much more reliable. In particular:
296 - Debugging threaded applications is now possible again. Previously,
297 GDB would hang while starting the program, or while waiting for
298 the program to stop at a breakpoint.
299 - Attaching to a running process no longer hangs.
300 - An error occurring while loading a core file has been fixed.
301 - Changing the value of the PC register now works again. This fixes
302 problems observed when using the "jump" command, or when calling
303 a function from GDB, or even when assigning a new value to $pc.
304 - With the "finish" and "return" commands, the return value for functions
305 returning a small array is now correctly printed.
306 - It is now possible to break on shared library code which gets executed
307 during a shared library init phase (code executed while executing
308 their .init section). Previously, the breakpoint would have no effect.
309 - GDB is now able to backtrace through the signal handler for
310 non-threaded programs.
312 PIE (Position Independent Executable) programs debugging is now supported.
313 This includes debugging execution of PIC (Position Independent Code) shared
314 libraries although for that, it should be possible to run such libraries as an
317 *** Changes in GDB 7.0
319 * GDB now has an interface for JIT compilation. Applications that
320 dynamically generate code can create symbol files in memory and register
321 them with GDB. For users, the feature should work transparently, and
322 for JIT developers, the interface is documented in the GDB manual in the
323 "JIT Compilation Interface" chapter.
325 * Tracepoints may now be conditional. The syntax is as for
326 breakpoints; either an "if" clause appended to the "trace" command,
327 or the "condition" command is available. GDB sends the condition to
328 the target for evaluation using the same bytecode format as is used
329 for tracepoint actions.
331 * "disassemble" command with a /r modifier, print the raw instructions
332 in hex as well as in symbolic form.
334 * Process record and replay
336 In a architecture environment that supports ``process record and
337 replay'', ``process record and replay'' target can record a log of
338 the process execution, and replay it with both forward and reverse
341 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
342 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
343 set execution-direction {forward|reverse}, for targets that support
346 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
347 feature is available with a native GDB running on kernel version
350 * GDB now has support for multi-byte and wide character sets on the
351 target. Strings whose character type is wchar_t, char16_t, or
352 char32_t are now correctly printed. GDB supports wide- and unicode-
353 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
354 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
355 `printf'. This feature requires iconv to work properly; if your
356 system does not have a working iconv, GDB can use GNU libiconv. See
357 the installation instructions for more information.
359 * GDB now supports automatic retrieval of shared library files from
360 remote targets. To use this feature, specify a system root that begins
361 with the `remote:' prefix, either via the `set sysroot' command or via
362 the `--with-sysroot' configure-time option.
364 * "info sharedlibrary" now takes an optional regex of libraries to show,
365 and it now reports if a shared library has no debugging information.
367 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
368 now complete on file names.
370 * When completing in expressions, gdb will attempt to limit
371 completions to allowable structure or union fields, where appropriate.
372 For instance, consider:
374 # struct example { int f1; double f2; };
375 # struct example variable;
378 If the user types TAB at the end of this command line, the available
379 completions will be "f1" and "f2".
381 * Inlined functions are now supported. They show up in backtraces, and
382 the "step", "next", and "finish" commands handle them automatically.
384 * GDB now supports the token-splicing (##) and stringification (#)
385 operators when expanding macros. It also supports variable-arity
388 * GDB now supports inspecting extra signal information, exported by
389 the new $_siginfo convenience variable. The feature is currently
390 implemented on linux ARM, i386 and amd64.
392 * GDB can now display the VFP floating point registers and NEON vector
393 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
394 can provide these registers (requires Linux 2.6.30 or later). Remote
395 and simulator targets may also provide them.
400 Search memory for a sequence of bytes.
403 Turn off `+'/`-' protocol acknowledgments to permit more efficient
404 operation over reliable transport links. Use of this packet is
405 controlled by the `set remote noack-packet' command.
408 Kill the process with the specified process ID. Use this in preference
409 to `k' when multiprocess protocol extensions are supported.
412 Obtains additional operating system information
416 Read or write additional signal information.
418 * Removed remote protocol undocumented extension
420 An undocumented extension to the remote protocol's `S' stop reply
421 packet that permited the stub to pass a process id was removed.
422 Remote servers should use the `T' stop reply packet instead.
424 * The "disassemble" command now supports an optional /m modifier to print mixed
427 * GDB now supports multiple function calling conventions according to the
428 DWARF-2 DW_AT_calling_convention function attribute.
430 * The SH target utilizes the aforementioned change to distinguish between gcc
431 and Renesas calling convention. It also adds the new CLI commands
432 `set/show sh calling-convention'.
434 * GDB can now read compressed debug sections, as produced by GNU gold
435 with the --compress-debug-sections=zlib flag.
437 * 64-bit core files are now supported on AIX.
439 * Thread switching is now supported on Tru64.
441 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
442 which will be allocated using malloc later in program execution.
444 * The qXfer:libraries:read remote procotol packet now allows passing a
445 list of section offsets.
447 * On GNU/Linux, GDB can now attach to stopped processes. Several race
448 conditions handling signals delivered during attach or thread creation
449 have also been fixed.
451 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
452 From the user's standpoint, all unqualified instances of True and False
453 are treated as the standard definitions, regardless of context.
455 * GDB now parses C++ symbol and type names more flexibly. For
458 template<typename T> class C { };
461 GDB will now correctly handle all of:
463 ptype C<char const *>
465 ptype C<const char *>
468 * New features in the GDB remote stub, gdbserver
470 - The "--wrapper" command-line argument tells gdbserver to use a
471 wrapper program to launch programs for debugging.
473 - On PowerPC and S/390 targets, it is now possible to use a single
474 gdbserver executable to debug both 32-bit and 64-bit programs.
475 (This requires gdbserver itself to be built as a 64-bit executable.)
477 - gdbserver uses the new noack protocol mode for TCP connections to
478 reduce communications latency, if also supported and enabled in GDB.
480 - Support for the sparc64-linux-gnu target is now included in
483 - The amd64-linux build of gdbserver now supports debugging both
484 32-bit and 64-bit programs.
486 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
487 now support hardware watchpoints, and will use them automatically
492 GDB now has support for scripting using Python. Whether this is
493 available is determined at configure time.
495 New GDB commands can now be written in Python.
497 * Ada tasking support
499 Ada tasks can now be inspected in GDB. The following commands have
503 Print the list of Ada tasks.
505 Print detailed information about task number N.
507 Print the task number of the current task.
509 Switch the context of debugging to task number N.
511 * Support for user-defined prefixed commands. The "define" command can
512 add new commands to existing prefixes, e.g. "target".
514 * Multi-inferior, multi-process debugging.
516 GDB now has generalized support for multi-inferior debugging. See
517 "Debugging Multiple Inferiors" in the manual for more information.
518 Although availability still depends on target support, the command
519 set is more uniform now. The GNU/Linux specific multi-forks support
520 has been migrated to this new framework. This implied some user
521 visible changes; see "New commands" and also "Removed commands"
524 * Target descriptions can now describe the target OS ABI. See the
525 "Target Description Format" section in the user manual for more
528 * Target descriptions can now describe "compatible" architectures
529 to indicate that the target can execute applications for a different
530 architecture in addition to those for the main target architecture.
531 See the "Target Description Format" section in the user manual for
534 * Multi-architecture debugging.
536 GDB now includes general supports for debugging applications on
537 hybrid systems that use more than one single processor architecture
538 at the same time. Each such hybrid architecture still requires
539 specific support to be added. The only hybrid architecture supported
540 in this version of GDB is the Cell Broadband Engine.
542 * GDB now supports integrated debugging of Cell/B.E. applications that
543 use both the PPU and SPU architectures. To enable support for hybrid
544 Cell/B.E. debugging, you need to configure GDB to support both the
545 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
546 --enable-targets configure option.
548 * Non-stop mode debugging.
550 For some targets, GDB now supports an optional mode of operation in
551 which you can examine stopped threads while other threads continue
552 to execute freely. This is referred to as non-stop mode, with the
553 old mode referred to as all-stop mode. See the "Non-Stop Mode"
554 section in the user manual for more information.
556 To be able to support remote non-stop debugging, a remote stub needs
557 to implement the non-stop mode remote protocol extensions, as
558 described in the "Remote Non-Stop" section of the user manual. The
559 GDB remote stub, gdbserver, has been adjusted to support these
560 extensions on linux targets.
562 * New commands (for set/show, see "New options" below)
564 catch syscall [NAME(S) | NUMBER(S)]
565 Catch system calls. Arguments, which should be names of system
566 calls or their numbers, mean catch only those syscalls. Without
567 arguments, every syscall will be caught. When the inferior issues
568 any of the specified syscalls, GDB will stop and announce the system
569 call, both when it is called and when its call returns. This
570 feature is currently available with a native GDB running on the
571 Linux Kernel, under the following architectures: x86, x86_64,
572 PowerPC and PowerPC64.
574 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
576 Search memory for a sequence of bytes.
578 maint set python print-stack
579 maint show python print-stack
580 Show a stack trace when an error is encountered in a Python script.
583 Invoke CODE by passing it to the Python interpreter.
588 These allow macros to be defined, undefined, and listed
592 Show operating system information about processes.
595 List the inferiors currently under GDB's control.
598 Switch focus to inferior number NUM.
601 Detach from inferior number NUM.
604 Kill inferior number NUM.
609 show spu stop-on-load
610 Control whether to stop for new SPE threads during Cell/B.E. debugging.
612 set spu auto-flush-cache
613 show spu auto-flush-cache
614 Control whether to automatically flush the software-managed cache
615 during Cell/B.E. debugging.
617 set sh calling-convention
618 show sh calling-convention
619 Control the calling convention used when calling SH target functions.
623 Control display of timestamps with GDB debugging output.
625 set disassemble-next-line
626 show disassemble-next-line
627 Control display of disassembled source lines or instructions when
630 set remote noack-packet
631 show remote noack-packet
632 Set/show the use of remote protocol QStartNoAckMode packet. See above
633 under "New remote packets."
635 set remote query-attached-packet
636 show remote query-attached-packet
637 Control use of remote protocol `qAttached' (query-attached) packet.
639 set remote read-siginfo-object
640 show remote read-siginfo-object
641 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
644 set remote write-siginfo-object
645 show remote write-siginfo-object
646 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
649 set remote reverse-continue
650 show remote reverse-continue
651 Control use of remote protocol 'bc' (reverse-continue) packet.
653 set remote reverse-step
654 show remote reverse-step
655 Control use of remote protocol 'bs' (reverse-step) packet.
657 set displaced-stepping
658 show displaced-stepping
659 Control displaced stepping mode. Displaced stepping is a way to
660 single-step over breakpoints without removing them from the debuggee.
661 Also known as "out-of-line single-stepping".
665 Control display of debugging info for displaced stepping.
667 maint set internal-error
668 maint show internal-error
669 Control what GDB does when an internal error is detected.
671 maint set internal-warning
672 maint show internal-warning
673 Control what GDB does when an internal warning is detected.
678 Use a wrapper program to launch programs for debugging.
680 set multiple-symbols (all|ask|cancel)
681 show multiple-symbols
682 The value of this variable can be changed to adjust the debugger behavior
683 when an expression or a breakpoint location contains an ambiguous symbol
684 name (an overloaded function name, for instance).
686 set breakpoint always-inserted
687 show breakpoint always-inserted
688 Keep breakpoints always inserted in the target, as opposed to inserting
689 them when resuming the target, and removing them when the target stops.
690 This option can improve debugger performance on slow remote targets.
692 set arm fallback-mode (arm|thumb|auto)
693 show arm fallback-mode
694 set arm force-mode (arm|thumb|auto)
696 These commands control how ARM GDB determines whether instructions
697 are ARM or Thumb. The default for both settings is auto, which uses
698 the current CPSR value for instructions without symbols; previous
699 versions of GDB behaved as if "set arm fallback-mode arm".
701 set disable-randomization
702 show disable-randomization
703 Standalone programs run with the virtual address space randomization enabled
704 by default on some platforms. This option keeps the addresses stable across
705 multiple debugging sessions.
709 Control whether other threads are stopped or not when some thread hits
714 Requests that asynchronous execution is enabled in the target, if available.
715 In this case, it's possible to resume target in the background, and interact
716 with GDB while the target is running. "show target-async" displays the
717 current state of asynchronous execution of the target.
719 set target-wide-charset
720 show target-wide-charset
721 The target-wide-charset is the name of the character set that GDB
722 uses when printing characters whose type is wchar_t.
724 set tcp auto-retry (on|off)
726 set tcp connect-timeout
727 show tcp connect-timeout
728 These commands allow GDB to retry failed TCP connections to a remote stub
729 with a specified timeout period; this is useful if the stub is launched
730 in parallel with GDB but may not be ready to accept connections immediately.
732 set libthread-db-search-path
733 show libthread-db-search-path
734 Control list of directories which GDB will search for appropriate
737 set schedule-multiple (on|off)
738 show schedule-multiple
739 Allow GDB to resume all threads of all processes or only threads of
744 Use more aggressive caching for accesses to the stack. This improves
745 performance of remote debugging (particularly backtraces) without
746 affecting correctness.
748 set interactive-mode (on|off|auto)
749 show interactive-mode
750 Control whether GDB runs in interactive mode (on) or not (off).
751 When in interactive mode, GDB waits for the user to answer all
752 queries. Otherwise, GDB does not wait and assumes the default
753 answer. When set to auto (the default), GDB determines which
754 mode to use based on the stdin settings.
759 For program forks, this is replaced by the new more generic `info
760 inferiors' command. To list checkpoints, you can still use the
761 `info checkpoints' command, which was an alias for the `info forks'
765 Replaced by the new `inferior' command. To switch between
766 checkpoints, you can still use the `restart' command, which was an
767 alias for the `fork' command.
770 This is removed, since some targets don't have a notion of
771 processes. To switch between processes, you can still use the
772 `inferior' command using GDB's own inferior number.
775 For program forks, this is replaced by the new more generic `kill
776 inferior' command. To delete a checkpoint, you can still use the
777 `delete checkpoint' command, which was an alias for the `delete
781 For program forks, this is replaced by the new more generic `detach
782 inferior' command. To detach a checkpoint, you can still use the
783 `detach checkpoint' command, which was an alias for the `detach
786 * New native configurations
788 x86/x86_64 Darwin i[34567]86-*-darwin*
790 x86_64 MinGW x86_64-*-mingw*
794 Lattice Mico32 lm32-*
795 x86 DICOS i[34567]86-*-dicos*
796 x86_64 DICOS x86_64-*-dicos*
799 * The GDB remote stub, gdbserver, now supports x86 Windows CE
800 (mingw32ce) debugging.
806 These commands were actually not implemented on any target.
808 *** Changes in GDB 6.8
810 * New native configurations
812 NetBSD/hppa hppa*-*netbsd*
813 Xtensa GNU/Linux xtensa*-*-linux*
817 NetBSD/hppa hppa*-*-netbsd*
818 Xtensa GNU/Lunux xtensa*-*-linux*
820 * Change in command line behavior -- corefiles vs. process ids.
822 When the '-p NUMBER' or '--pid NUMBER' options are used, and
823 attaching to process NUMBER fails, GDB no longer attempts to open a
824 core file named NUMBER. Attaching to a program using the -c option
825 is no longer supported. Instead, use the '-p' or '--pid' options.
827 * GDB can now be built as a native debugger for debugging Windows x86
828 (mingw32) Portable Executable (PE) programs.
830 * Pending breakpoints no longer change their number when their address
833 * GDB now supports breakpoints with multiple locations,
834 including breakpoints on C++ constructors, inside C++ templates,
835 and in inlined functions.
837 * GDB's ability to debug optimized code has been improved. GDB more
838 accurately identifies function bodies and lexical blocks that occupy
839 more than one contiguous range of addresses.
841 * Target descriptions can now describe registers for PowerPC.
843 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
844 registers on PowerPC targets.
846 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
847 targets even when the libthread_db library is not available.
849 * The GDB remote stub, gdbserver, now supports the new file transfer
850 commands (remote put, remote get, and remote delete).
852 * The GDB remote stub, gdbserver, now supports run and attach in
853 extended-remote mode.
855 * hppa*64*-*-hpux11* target broken
856 The debugger is unable to start a program and fails with the following
857 error: "Error trying to get information about dynamic linker".
858 The gdb-6.7 release is also affected.
860 * GDB now supports the --enable-targets= configure option to allow
861 building a single GDB executable that supports multiple remote
862 target architectures.
864 * GDB now supports debugging C and C++ programs which use the
865 Decimal Floating Point extension. In addition, the PowerPC target
866 now has a set of pseudo-registers to inspect decimal float values
867 stored in two consecutive float registers.
869 * The -break-insert MI command can optionally create pending
872 * Improved support for debugging Ada
873 Many improvements to the Ada language support have been made. These
875 - Better support for Ada2005 interface types
876 - Improved handling of arrays and slices in general
877 - Better support for Taft-amendment types
878 - The '{type} ADDRESS' expression is now allowed on the left hand-side
880 - Improved command completion in Ada
883 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
888 set print frame-arguments (all|scalars|none)
889 show print frame-arguments
890 The value of this variable can be changed to control which argument
891 values should be printed by the debugger when displaying a frame.
896 Transfer files to and from a remote target, and delete remote files.
903 Transfer files to and from a remote target, and delete remote files.
912 Open, close, read, write, and delete files on the remote system.
915 Attach to an existing process on the remote system, in extended-remote
919 Run a new process on the remote system, in extended-remote mode.
921 *** Changes in GDB 6.7
923 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
924 bfd, libiberty and opcodes, as revealed by static analysis donated by
925 Coverity, Inc. (http://scan.coverity.com).
927 * When looking up multiply-defined global symbols, GDB will now prefer the
928 symbol definition in the current shared library if it was built using the
929 -Bsymbolic linker option.
931 * When the Text User Interface (TUI) is not configured, GDB will now
932 recognize the -tui command-line option and print a message that the TUI
935 * The GDB remote stub, gdbserver, now has lower overhead for high
936 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
938 * GDB for MIPS targets now autodetects whether a remote target provides
939 32-bit or 64-bit register values.
941 * Support for C++ member pointers has been improved.
943 * GDB now understands XML target descriptions, which specify the
944 target's overall architecture. GDB can read a description from
945 a local file or over the remote serial protocol.
947 * Vectors of single-byte data use a new integer type which is not
948 automatically displayed as character or string data.
950 * The /s format now works with the print command. It displays
951 arrays of single-byte integers and pointers to single-byte integers
954 * Target descriptions can now describe target-specific registers,
955 for architectures which have implemented the support (currently
956 only ARM, M68K, and MIPS).
958 * GDB and the GDB remote stub, gdbserver, now support the XScale
961 * The GDB remote stub, gdbserver, has been updated to support
962 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
963 has been rewritten to use the standard GDB remote protocol.
965 * GDB can now step into C++ functions which are called through thunks.
967 * GDB for the Cell/B.E. SPU now supports overlay debugging.
969 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
970 layout. It also supports a TextSeg= and DataSeg= response when only
971 segment base addresses (rather than offsets) are available.
973 * The /i format now outputs any trailing branch delay slot instructions
974 immediately following the last instruction within the count specified.
976 * The GDB remote protocol "T" stop reply packet now supports a
977 "library" response. Combined with the new "qXfer:libraries:read"
978 packet, this response allows GDB to debug shared libraries on targets
979 where the operating system manages the list of loaded libraries (e.g.
980 Windows and SymbianOS).
982 * The GDB remote stub, gdbserver, now supports dynamic link libraries
983 (DLLs) on Windows and Windows CE targets.
985 * GDB now supports a faster verification that a .debug file matches its binary
986 according to its build-id signature, if the signature is present.
992 Enable or disable hardware flow control (RTS/CTS) on the serial port
993 when debugging using remote targets.
995 set mem inaccessible-by-default
996 show mem inaccessible-by-default
997 If the target supplies a memory map, for instance via the remote
998 protocol's "qXfer:memory-map:read" packet, setting this variable
999 prevents GDB from accessing memory outside the memory map. This
1000 is useful for targets with memory mapped registers or which react
1001 badly to accesses of unmapped address space.
1003 set breakpoint auto-hw
1004 show breakpoint auto-hw
1005 If the target supplies a memory map, for instance via the remote
1006 protocol's "qXfer:memory-map:read" packet, setting this variable
1007 lets GDB use hardware breakpoints automatically for memory regions
1008 where it can not use software breakpoints. This covers both the
1009 "break" command and internal breakpoints used for other commands
1010 including "next" and "finish".
1013 catch exception unhandled
1014 Stop the program execution when Ada exceptions are raised.
1017 Stop the program execution when an Ada assertion failed.
1021 Set an alternate system root for target files. This is a more
1022 general version of "set solib-absolute-prefix", which is now
1023 an alias to "set sysroot".
1026 Provide extended SPU facility status information. This set of
1027 commands is available only when debugging the Cell/B.E. SPU
1030 * New native configurations
1032 OpenBSD/sh sh*-*openbsd*
1035 unset tdesc filename
1037 Use the specified local file as an XML target description, and do
1038 not query the target for its built-in description.
1042 OpenBSD/sh sh*-*-openbsd*
1043 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1044 Toshiba Media Processor mep-elf
1046 * New remote packets
1049 Ignore the specified signals; pass them directly to the debugged program
1050 without stopping other threads or reporting them to GDB.
1052 qXfer:features:read:
1053 Read an XML target description from the target, which describes its
1058 Read or write contents of an spufs file on the target system. These
1059 packets are available only on the Cell/B.E. SPU architecture.
1061 qXfer:libraries:read:
1062 Report the loaded shared libraries. Combined with new "T" packet
1063 response, this packet allows GDB to debug shared libraries on
1064 targets where the operating system manages the list of loaded
1065 libraries (e.g. Windows and SymbianOS).
1069 Support for these obsolete configurations has been removed.
1077 i[34567]86-*-lynxos*
1078 i[34567]86-*-netware*
1079 i[34567]86-*-sco3.2v5*
1080 i[34567]86-*-sco3.2v4*
1082 i[34567]86-*-sysv4.2*
1085 i[34567]86-*-unixware2*
1086 i[34567]86-*-unixware*
1095 * Other removed features
1102 Various m68k-only ROM monitors.
1109 Various Renesas ROM monitors and debugging interfaces for SH and
1114 Support for a Macraigor serial interface to on-chip debugging.
1115 GDB does not directly support the newer parallel or USB
1120 A debug information format. The predecessor to DWARF 2 and
1121 DWARF 3, which are still supported.
1123 Support for the HP aCC compiler on HP-UX/PA-RISC
1125 SOM-encapsulated symbolic debugging information, automatic
1126 invocation of pxdb, and the aCC custom C++ ABI. This does not
1127 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1128 with aCC can still be debugged on an assembly level.
1130 MIPS ".pdr" sections
1132 A MIPS-specific format used to describe stack frame layout
1133 in debugging information.
1137 GDB could work with an older version of Guile to debug
1138 the interpreter and Scheme programs running in it.
1140 set mips stack-arg-size
1141 set mips saved-gpreg-size
1143 Use "set mips abi" to control parameter passing for MIPS.
1145 *** Changes in GDB 6.6
1150 Cell Broadband Engine SPU spu-elf
1152 * GDB can now be configured as a cross-debugger targeting native Windows
1153 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1154 running on a Windows system over TCP/IP to debug Windows programs.
1156 * The GDB remote stub, gdbserver, has been updated to support Windows and
1157 Cygwin debugging. Both single-threaded and multi-threaded programs are
1160 * The "set trust-readonly-sections" command works again. This command was
1161 broken in GDB 6.3, 6.4, and 6.5.
1163 * The "load" command now supports writing to flash memory, if the remote
1164 stub provides the required support.
1166 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1167 longer requires symbolic debug information (e.g. DWARF-2).
1172 unset substitute-path
1173 show substitute-path
1174 Manage a list of substitution rules that GDB uses to rewrite the name
1175 of the directories where the sources are located. This can be useful
1176 for instance when the sources were moved to a different location
1177 between compilation and debugging.
1181 Print each CLI command as it is executed. Each command is prefixed with
1182 a number of `+' symbols representing the nesting depth.
1183 The source command now has a `-v' option to enable the same feature.
1187 The ARM Demon monitor support (RDP protocol, "target rdp").
1189 Kernel Object Display, an embedded debugging feature which only worked with
1190 an obsolete version of Cisco IOS.
1192 The 'set download-write-size' and 'show download-write-size' commands.
1194 * New remote packets
1197 Tell a stub about GDB client features, and request remote target features.
1198 The first feature implemented is PacketSize, which allows the target to
1199 specify the size of packets it can handle - to minimize the number of
1200 packets required and improve performance when connected to a remote
1204 Fetch an OS auxilliary vector from the remote stub. This packet is a
1205 more efficient replacement for qPart:auxv:read.
1207 qXfer:memory-map:read:
1208 Fetch a memory map from the remote stub, including information about
1209 RAM, ROM, and flash memory devices.
1214 Erase and program a flash memory device.
1216 * Removed remote packets
1219 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1220 used it, and only gdbserver implemented it.
1222 *** Changes in GDB 6.5
1226 Renesas M32C/M16C m32c-elf
1228 Morpho Technologies ms1 ms1-elf
1232 init-if-undefined Initialize a convenience variable, but
1233 only if it doesn't already have a value.
1235 The following commands are presently only implemented for native GNU/Linux:
1237 checkpoint Save a snapshot of the program state.
1239 restart <n> Return the program state to a
1240 previously saved state.
1242 info checkpoints List currently saved checkpoints.
1244 delete-checkpoint <n> Delete a previously saved checkpoint.
1246 set|show detach-on-fork Tell gdb whether to detach from a newly
1247 forked process, or to keep debugging it.
1249 info forks List forks of the user program that
1250 are available to be debugged.
1252 fork <n> Switch to debugging one of several
1253 forks of the user program that are
1254 available to be debugged.
1256 delete-fork <n> Delete a fork from the list of forks
1257 that are available to be debugged (and
1258 kill the forked process).
1260 detach-fork <n> Delete a fork from the list of forks
1261 that are available to be debugged (and
1262 allow the process to continue).
1266 Morpho Technologies ms2 ms1-elf
1268 * Improved Windows host support
1270 GDB now builds as a cross debugger hosted on i686-mingw32, including
1271 native console support, and remote communications using either
1272 network sockets or serial ports.
1274 * Improved Modula-2 language support
1276 GDB can now print most types in the Modula-2 syntax. This includes:
1277 basic types, set types, record types, enumerated types, range types,
1278 pointer types and ARRAY types. Procedure var parameters are correctly
1279 printed and hexadecimal addresses and character constants are also
1280 written in the Modula-2 syntax. Best results can be obtained by using
1281 GNU Modula-2 together with the -gdwarf-2 command line option.
1285 The ARM rdi-share module.
1287 The Netware NLM debug server.
1289 *** Changes in GDB 6.4
1291 * New native configurations
1293 OpenBSD/arm arm*-*-openbsd*
1294 OpenBSD/mips64 mips64-*-openbsd*
1298 Morpho Technologies ms1 ms1-elf
1300 * New command line options
1302 --batch-silent As for --batch, but totally silent.
1303 --return-child-result The debugger will exist with the same value
1304 the child (debugged) program exited with.
1305 --eval-command COMMAND, -ex COMMAND
1306 Execute a single GDB CLI command. This may be
1307 specified multiple times and in conjunction
1308 with the --command (-x) option.
1310 * Deprecated commands removed
1312 The following commands, that were deprecated in 2000, have been
1316 set|show arm disassembly-flavor set|show arm disassembler
1317 othernames set arm disassembler
1318 set|show remotedebug set|show debug remote
1319 set|show archdebug set|show debug arch
1320 set|show eventdebug set|show debug event
1323 * New BSD user-level threads support
1325 It is now possible to debug programs using the user-level threads
1326 library on OpenBSD and FreeBSD. Currently supported (target)
1329 FreeBSD/amd64 x86_64-*-freebsd*
1330 FreeBSD/i386 i386-*-freebsd*
1331 OpenBSD/i386 i386-*-openbsd*
1333 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1334 are not yet supported.
1336 * New support for Matsushita MN10300 w/sim added
1337 (Work in progress). mn10300-elf.
1339 * REMOVED configurations and files
1341 VxWorks and the XDR protocol *-*-vxworks
1342 Motorola MCORE mcore-*-*
1343 National Semiconductor NS32000 ns32k-*-*
1345 * New "set print array-indexes" command
1347 After turning this setting "on", GDB prints the index of each element
1348 when displaying arrays. The default is "off" to preserve the previous
1351 * VAX floating point support
1353 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1355 * User-defined command support
1357 In addition to using $arg0..$arg9 for argument passing, it is now possible
1358 to use $argc to determine now many arguments have been passed. See the
1359 section on user-defined commands in the user manual for more information.
1361 *** Changes in GDB 6.3:
1363 * New command line option
1365 GDB now accepts -l followed by a number to set the timeout for remote
1368 * GDB works with GCC -feliminate-dwarf2-dups
1370 GDB now supports a more compact representation of DWARF-2 debug
1371 information using DW_FORM_ref_addr references. These are produced
1372 by GCC with the option -feliminate-dwarf2-dups and also by some
1373 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1374 to use -feliminate-dwarf2-dups.
1376 * Internationalization
1378 When supported by the host system, GDB will be built with
1379 internationalization (libintl). The task of marking up the sources is
1380 continued, we're looking forward to our first translation.
1384 Initial support for debugging programs compiled with the GNAT
1385 implementation of the Ada programming language has been integrated
1386 into GDB. In this release, support is limited to expression evaluation.
1388 * New native configurations
1390 GNU/Linux/m32r m32r-*-linux-gnu
1394 GDB's remote protocol now includes support for the 'p' packet. This
1395 packet is used to fetch individual registers from a remote inferior.
1397 * END-OF-LIFE registers[] compatibility module
1399 GDB's internal register infrastructure has been completely rewritten.
1400 The new infrastructure making possible the implementation of key new
1401 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1404 GDB 6.3 will be the last release to include the the registers[]
1405 compatibility module that allowed out-of-date configurations to
1406 continue to work. This change directly impacts the following
1416 powerpc bdm protocol
1418 Unless there is activity to revive these configurations, they will be
1419 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1421 * OBSOLETE configurations and files
1423 Configurations that have been declared obsolete in this release have
1424 been commented out. Unless there is activity to revive these
1425 configurations, the next release of GDB will have their sources
1426 permanently REMOVED.
1435 *** Changes in GDB 6.2.1:
1437 * MIPS `break main; run' gave an heuristic-fence-post warning
1439 When attempting to run even a simple program, a warning about
1440 heuristic-fence-post being hit would be reported. This problem has
1443 * MIPS IRIX 'long double' crashed GDB
1445 When examining a long double variable, GDB would get a segmentation
1446 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1447 IRIX long double values).
1451 A bug in the VAX stack code was causing problems with the "next"
1452 command. This problem has been fixed.
1454 *** Changes in GDB 6.2:
1456 * Fix for ``many threads''
1458 On GNU/Linux systems that use the NPTL threads library, a program
1459 rapidly creating and deleting threads would confuse GDB leading to the
1462 ptrace: No such process.
1463 thread_db_get_info: cannot get thread info: generic error
1465 This problem has been fixed.
1467 * "-async" and "-noasync" options removed.
1469 Support for the broken "-noasync" option has been removed (it caused
1472 * New ``start'' command.
1474 This command runs the program until the begining of the main procedure.
1476 * New BSD Kernel Data Access Library (libkvm) interface
1478 Using ``target kvm'' it is now possible to debug kernel core dumps and
1479 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1480 platforms. Currently supported (native-only) configurations are:
1482 FreeBSD/amd64 x86_64-*-freebsd*
1483 FreeBSD/i386 i?86-*-freebsd*
1484 NetBSD/i386 i?86-*-netbsd*
1485 NetBSD/m68k m68*-*-netbsd*
1486 NetBSD/sparc sparc-*-netbsd*
1487 OpenBSD/amd64 x86_64-*-openbsd*
1488 OpenBSD/i386 i?86-*-openbsd*
1489 OpenBSD/m68k m68*-openbsd*
1490 OpenBSD/sparc sparc-*-openbsd*
1492 * Signal trampoline code overhauled
1494 Many generic problems with GDB's signal handling code have been fixed.
1495 These include: backtraces through non-contiguous stacks; recognition
1496 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1497 call; backtrace through a signal trampoline; step into and out of
1498 signal handlers; and single-stepping in the signal trampoline.
1500 Please note that kernel bugs are a limiting factor here. These
1501 features have been shown to work on an s390 GNU/Linux system that
1502 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1504 * Cygwin support for DWARF 2 added.
1506 * New native configurations
1508 GNU/Linux/hppa hppa*-*-linux*
1509 OpenBSD/hppa hppa*-*-openbsd*
1510 OpenBSD/m68k m68*-*-openbsd*
1511 OpenBSD/m88k m88*-*-openbsd*
1512 OpenBSD/powerpc powerpc-*-openbsd*
1513 NetBSD/vax vax-*-netbsd*
1514 OpenBSD/vax vax-*-openbsd*
1516 * END-OF-LIFE frame compatibility module
1518 GDB's internal frame infrastructure has been completely rewritten.
1519 The new infrastructure making it possible to support key new features
1520 including DWARF 2 Call Frame Information. To aid in the task of
1521 migrating old configurations to this new infrastructure, a
1522 compatibility module, that allowed old configurations to continue to
1523 work, was also included.
1525 GDB 6.2 will be the last release to include this frame compatibility
1526 module. This change directly impacts the following configurations:
1536 Unless there is activity to revive these configurations, they will be
1537 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1539 * REMOVED configurations and files
1541 Sun 3, running SunOS 3 m68*-*-sunos3*
1542 Sun 3, running SunOS 4 m68*-*-sunos4*
1543 Sun 2, running SunOS 3 m68000-*-sunos3*
1544 Sun 2, running SunOS 4 m68000-*-sunos4*
1545 Motorola 680x0 running LynxOS m68*-*-lynxos*
1546 AT&T 3b1/Unix pc m68*-att-*
1547 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1548 decstation mips-dec-* mips-little-*
1549 riscos mips-*-riscos* mips-*-sysv*
1550 sonymips mips-sony-*
1551 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1553 *** Changes in GDB 6.1.1:
1555 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1557 The TUI (Text-mode User Interface) is now built as part of a default
1558 GDB configuration. It is enabled by either selecting the TUI with the
1559 command line option "-i=tui" or by running the separate "gdbtui"
1560 program. For more information on the TUI, see the manual "Debugging
1563 * Pending breakpoint support (also included in GDB 6.1)
1565 Support has been added to allow you to specify breakpoints in shared
1566 libraries that have not yet been loaded. If a breakpoint location
1567 cannot be found, and the "breakpoint pending" option is set to auto,
1568 GDB queries you if you wish to make the breakpoint pending on a future
1569 shared-library load. If and when GDB resolves the breakpoint symbol,
1570 the pending breakpoint is removed as one or more regular breakpoints
1573 Pending breakpoints are very useful for GCJ Java debugging.
1575 * Fixed ISO-C build problems
1577 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1578 non ISO-C code that stopped them being built using a more strict ISO-C
1579 compiler (e.g., IBM's C compiler).
1581 * Fixed build problem on IRIX 5
1583 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1584 wasn't able to compile compile on an IRIX 5 system.
1586 * Added execute permission to gdb/gdbserver/configure
1588 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1589 permission. This bug would cause configure to fail on a number of
1590 systems (Solaris, IRIX). Ref: server/519.
1592 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1594 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1595 has been updated to use constant array sizes.
1597 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1599 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1600 its generated DWARF Call Frame Info. This encoding was causing GDB to
1601 panic, that panic has been fixed. Ref: gdb/1628.
1603 * Fixed a problem when examining parameters in shared library code.
1605 When examining parameters in optimized shared library code generated
1606 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1607 not available''. GDB now correctly displays the variable's value.
1609 *** Changes in GDB 6.1:
1611 * Removed --with-mmalloc
1613 Support for the mmalloc memory manager has been removed, as it
1614 conflicted with the internal gdb byte cache.
1616 * Changes in AMD64 configurations
1618 The AMD64 target now includes the %cs and %ss registers. As a result
1619 the AMD64 remote protocol has changed; this affects the floating-point
1620 and SSE registers. If you rely on those registers for your debugging,
1621 you should upgrade gdbserver on the remote side.
1623 * Revised SPARC target
1625 The SPARC target has been completely revised, incorporating the
1626 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1627 support for LynxOS and SunOS 4 has been dropped. Calling functions
1628 from within GDB on operating systems with a non-executable stack
1629 (Solaris, OpenBSD) now works.
1633 GDB has a new C++ demangler which does a better job on the mangled
1634 names generated by current versions of g++. It also runs faster, so
1635 with this and other changes gdb should now start faster on large C++
1638 * DWARF 2 Location Expressions
1640 GDB support for location expressions has been extended to support function
1641 arguments and frame bases. Older versions of GDB could crash when they
1644 * C++ nested types and namespaces
1646 GDB's support for nested types and namespaces in C++ has been
1647 improved, especially if you use the DWARF 2 debugging format. (This
1648 is the default for recent versions of GCC on most platforms.)
1649 Specifically, if you have a class "Inner" defined within a class or
1650 namespace "Outer", then GDB realizes that the class's name is
1651 "Outer::Inner", not simply "Inner". This should greatly reduce the
1652 frequency of complaints about not finding RTTI symbols. In addition,
1653 if you are stopped at inside of a function defined within a namespace,
1654 GDB modifies its name lookup accordingly.
1656 * New native configurations
1658 NetBSD/amd64 x86_64-*-netbsd*
1659 OpenBSD/amd64 x86_64-*-openbsd*
1660 OpenBSD/alpha alpha*-*-openbsd*
1661 OpenBSD/sparc sparc-*-openbsd*
1662 OpenBSD/sparc64 sparc64-*-openbsd*
1664 * New debugging protocols
1666 M32R with SDI protocol m32r-*-elf*
1668 * "set prompt-escape-char" command deleted.
1670 The command "set prompt-escape-char" has been deleted. This command,
1671 and its very obscure effet on GDB's prompt, was never documented,
1672 tested, nor mentioned in the NEWS file.
1674 * OBSOLETE configurations and files
1676 Configurations that have been declared obsolete in this release have
1677 been commented out. Unless there is activity to revive these
1678 configurations, the next release of GDB will have their sources
1679 permanently REMOVED.
1681 Sun 3, running SunOS 3 m68*-*-sunos3*
1682 Sun 3, running SunOS 4 m68*-*-sunos4*
1683 Sun 2, running SunOS 3 m68000-*-sunos3*
1684 Sun 2, running SunOS 4 m68000-*-sunos4*
1685 Motorola 680x0 running LynxOS m68*-*-lynxos*
1686 AT&T 3b1/Unix pc m68*-att-*
1687 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1688 decstation mips-dec-* mips-little-*
1689 riscos mips-*-riscos* mips-*-sysv*
1690 sonymips mips-sony-*
1691 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1693 * REMOVED configurations and files
1695 SGI Irix-4.x mips-sgi-irix4 or iris4
1696 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1697 Z8000 simulator z8k-zilog-none or z8ksim
1698 Matsushita MN10200 w/simulator mn10200-*-*
1699 H8/500 simulator h8500-hitachi-hms or h8500hms
1700 HP/PA running BSD hppa*-*-bsd*
1701 HP/PA running OSF/1 hppa*-*-osf*
1702 HP/PA Pro target hppa*-*-pro*
1703 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1704 386BSD i[3456]86-*-bsd*
1705 Sequent family i[3456]86-sequent-sysv4*
1706 i[3456]86-sequent-sysv*
1707 i[3456]86-sequent-bsd*
1708 SPARC running LynxOS sparc-*-lynxos*
1709 SPARC running SunOS 4 sparc-*-sunos4*
1710 Tsqware Sparclet sparclet-*-*
1711 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1713 *** Changes in GDB 6.0:
1717 Support for debugging the Objective-C programming language has been
1718 integrated into GDB.
1720 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1722 DWARF 2's Call Frame Information makes available compiler generated
1723 information that more exactly describes the program's run-time stack.
1724 By using this information, GDB is able to provide more robust stack
1727 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1728 have been updated to use a new backtrace mechanism which includes
1729 DWARF 2 CFI support.
1733 GDB's remote protocol has been extended to include support for hosted
1734 file I/O (where the remote target uses GDB's file system). See GDB's
1735 remote protocol documentation for details.
1737 * All targets using the new architecture framework.
1739 All of GDB's targets have been updated to use the new internal
1740 architecture framework. The way is now open for future GDB releases
1741 to include cross-architecture native debugging support (i386 on amd64,
1744 * GNU/Linux's Thread Local Storage (TLS)
1746 GDB now includes support for for the GNU/Linux implementation of
1747 per-thread variables.
1749 * GNU/Linux's Native POSIX Thread Library (NPTL)
1751 GDB's thread code has been updated to work with either the new
1752 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1754 * Separate debug info.
1756 GDB, in conjunction with BINUTILS, now supports a mechanism for
1757 automatically loading debug information from a separate file. Instead
1758 of shipping full debug and non-debug versions of system libraries,
1759 system integrators can now instead ship just the stripped libraries
1760 and optional debug files.
1762 * DWARF 2 Location Expressions
1764 DWARF 2 Location Expressions allow the compiler to more completely
1765 describe the location of variables (even in optimized code) to the
1768 GDB now includes preliminary support for location expressions (support
1769 for DW_OP_piece is still missing).
1773 A number of long standing bugs that caused GDB to die while starting a
1774 Java application have been fixed. GDB's Java support is now
1775 considered "useable".
1777 * GNU/Linux support for fork, vfork, and exec.
1779 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1780 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1783 * GDB supports logging output to a file
1785 There are two new commands, "set logging" and "show logging", which can be
1786 used to capture GDB's output to a file.
1788 * The meaning of "detach" has changed for gdbserver
1790 The "detach" command will now resume the application, as documented. To
1791 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1794 * d10v, m68hc11 `regs' command deprecated
1796 The `info registers' command has been updated so that it displays the
1797 registers using a format identical to the old `regs' command.
1801 A new command, "maint set profile on/off", has been added. This command can
1802 be used to enable or disable profiling while running GDB, to profile a
1803 session or a set of commands. In addition there is a new configure switch,
1804 "--enable-profiling", which will cause GDB to be compiled with profiling
1805 data, for more informative profiling results.
1807 * Default MI syntax changed to "mi2".
1809 The default MI (machine interface) syntax, enabled by the command line
1810 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1811 "mi1", can be enabled by specifying the option "-i=mi1".
1813 Support for the original "mi0" syntax (included in GDB 5.0) has been
1816 Fix for gdb/192: removed extraneous space when displaying frame level.
1817 Fix for gdb/672: update changelist is now output in mi list format.
1818 Fix for gdb/702: a -var-assign that updates the value now shows up
1819 in a subsequent -var-update.
1821 * New native configurations.
1823 FreeBSD/amd64 x86_64-*-freebsd*
1825 * Multi-arched targets.
1827 HP/PA HPUX11 hppa*-*-hpux*
1828 Renesas M32R/D w/simulator m32r-*-elf*
1830 * OBSOLETE configurations and files
1832 Configurations that have been declared obsolete in this release have
1833 been commented out. Unless there is activity to revive these
1834 configurations, the next release of GDB will have their sources
1835 permanently REMOVED.
1837 Z8000 simulator z8k-zilog-none or z8ksim
1838 Matsushita MN10200 w/simulator mn10200-*-*
1839 H8/500 simulator h8500-hitachi-hms or h8500hms
1840 HP/PA running BSD hppa*-*-bsd*
1841 HP/PA running OSF/1 hppa*-*-osf*
1842 HP/PA Pro target hppa*-*-pro*
1843 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1844 Sequent family i[3456]86-sequent-sysv4*
1845 i[3456]86-sequent-sysv*
1846 i[3456]86-sequent-bsd*
1847 Tsqware Sparclet sparclet-*-*
1848 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1850 * REMOVED configurations and files
1853 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1854 IBM AIX PS/2 i[3456]86-*-aix
1855 i386 running Mach 3.0 i[3456]86-*-mach3*
1856 i386 running Mach i[3456]86-*-mach*
1857 i386 running OSF/1 i[3456]86-*osf1mk*
1858 HP/Apollo 68k Family m68*-apollo*-sysv*,
1860 m68*-hp-bsd*, m68*-hp-hpux*
1861 Argonaut Risc Chip (ARC) arc-*-*
1862 Mitsubishi D30V d30v-*-*
1863 Fujitsu FR30 fr30-*-elf*
1864 OS/9000 i[34]86-*-os9k
1865 I960 with MON960 i960-*-coff
1867 * MIPS $fp behavior changed
1869 The convenience variable $fp, for the MIPS, now consistently returns
1870 the address of the current frame's base. Previously, depending on the
1871 context, $fp could refer to either $sp or the current frame's base
1872 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1873 The GNU Source-Level Debugger''.
1875 *** Changes in GDB 5.3:
1877 * GNU/Linux shared library multi-threaded performance improved.
1879 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1880 `/proc', in preference to `ptrace' for memory reads. This may result
1881 in an improvement in the start-up time of multi-threaded, shared
1882 library applications when run under GDB. One GDB user writes: ``loads
1883 shared libs like mad''.
1885 * ``gdbserver'' now supports multi-threaded applications on some targets
1887 Support for debugging multi-threaded applications which use
1888 the GNU/Linux LinuxThreads package has been added for
1889 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1890 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1892 * GDB now supports C/C++ preprocessor macros.
1894 GDB now expands preprocessor macro invocations in C/C++ expressions,
1895 and provides various commands for showing macro definitions and how
1898 The new command `macro expand EXPRESSION' expands any macro
1899 invocations in expression, and shows the result.
1901 The new command `show macro MACRO-NAME' shows the definition of the
1902 macro named MACRO-NAME, and where it was defined.
1904 Most compilers don't include information about macros in the debugging
1905 information by default. In GCC 3.1, for example, you need to compile
1906 your program with the options `-gdwarf-2 -g3'. If the macro
1907 information is present in the executable, GDB will read it.
1909 * Multi-arched targets.
1911 DEC Alpha (partial) alpha*-*-*
1912 DEC VAX (partial) vax-*-*
1914 National Semiconductor NS32000 (partial) ns32k-*-*
1915 Motorola 68000 (partial) m68k-*-*
1916 Motorola MCORE mcore-*-*
1920 Fujitsu FRV architecture added by Red Hat frv*-*-*
1923 * New native configurations
1925 Alpha NetBSD alpha*-*-netbsd*
1926 SH NetBSD sh*-*-netbsdelf*
1927 MIPS NetBSD mips*-*-netbsd*
1928 UltraSPARC NetBSD sparc64-*-netbsd*
1930 * OBSOLETE configurations and files
1932 Configurations that have been declared obsolete in this release have
1933 been commented out. Unless there is activity to revive these
1934 configurations, the next release of GDB will have their sources
1935 permanently REMOVED.
1937 Mitsubishi D30V d30v-*-*
1938 OS/9000 i[34]86-*-os9k
1939 IBM AIX PS/2 i[3456]86-*-aix
1940 Fujitsu FR30 fr30-*-elf*
1941 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1942 Argonaut Risc Chip (ARC) arc-*-*
1943 i386 running Mach 3.0 i[3456]86-*-mach3*
1944 i386 running Mach i[3456]86-*-mach*
1945 i386 running OSF/1 i[3456]86-*osf1mk*
1946 HP/Apollo 68k Family m68*-apollo*-sysv*,
1948 m68*-hp-bsd*, m68*-hp-hpux*
1949 I960 with MON960 i960-*-coff
1951 * OBSOLETE languages
1953 CHILL, a Pascal like language used by telecommunications companies.
1955 * REMOVED configurations and files
1957 AMD 29k family via UDI a29k-amd-udi, udi29k
1958 A29K VxWorks a29k-*-vxworks
1959 AMD 29000 embedded, using EBMON a29k-none-none
1960 AMD 29000 embedded with COFF a29k-none-coff
1961 AMD 29000 embedded with a.out a29k-none-aout
1963 testsuite/gdb.hp/gdb.threads-hp/ directory
1965 * New command "set max-user-call-depth <nnn>"
1967 This command allows the user to limit the call depth of user-defined
1968 commands. The default is 1024.
1970 * Changes in FreeBSD/i386 native debugging.
1972 Support for the "generate-core-file" has been added.
1974 * New commands "dump", "append", and "restore".
1976 These commands allow data to be copied from target memory
1977 to a bfd-format or binary file (dump and append), and back
1978 from a file into memory (restore).
1980 * Improved "next/step" support on multi-processor Alpha Tru64.
1982 The previous single-step mechanism could cause unpredictable problems,
1983 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1984 of a software single-step mechanism prevents this.
1986 *** Changes in GDB 5.2.1:
1994 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1995 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1996 Fix, by Joel Brobecker imported from mainline.
1998 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1999 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2000 Fix, by Fred Fish, imported from mainline.
2002 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2003 Surprisingly enough, it works now.
2004 By Michal Ludvig, imported from mainline.
2006 i386 hardware watchpoint support:
2007 avoid misses on second run for some targets.
2008 By Pierre Muller, imported from mainline.
2010 *** Changes in GDB 5.2:
2012 * New command "set trust-readonly-sections on[off]".
2014 This command is a hint that tells gdb that read-only sections
2015 really are read-only (ie. that their contents will not change).
2016 In this mode, gdb will go to the object file rather than the
2017 target to read memory from read-only sections (such as ".text").
2018 This can be a significant performance improvement on some
2019 (notably embedded) targets.
2021 * New command "generate-core-file" (or "gcore").
2023 This new gdb command allows the user to drop a core file of the child
2024 process state at any time. So far it's been implemented only for
2025 GNU/Linux and Solaris, but should be relatively easily ported to other
2026 hosts. Argument is core file name (defaults to core.<pid>).
2028 * New command line option
2030 GDB now accepts --pid or -p followed by a process id.
2032 * Change in command line behavior -- corefiles vs. process ids.
2034 There is a subtle behavior in the way in which GDB handles
2035 command line arguments. The first non-flag argument is always
2036 a program to debug, but the second non-flag argument may either
2037 be a corefile or a process id. Previously, GDB would attempt to
2038 open the second argument as a corefile, and if that failed, would
2039 issue a superfluous error message and then attempt to attach it as
2040 a process. Now, if the second argument begins with a non-digit,
2041 it will be treated as a corefile. If it begins with a digit,
2042 GDB will attempt to attach it as a process, and if no such process
2043 is found, will then attempt to open it as a corefile.
2045 * Changes in ARM configurations.
2047 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2048 configuration is fully multi-arch.
2050 * New native configurations
2052 ARM NetBSD arm*-*-netbsd*
2053 x86 OpenBSD i[3456]86-*-openbsd*
2054 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2055 Sparc64 running FreeBSD sparc64-*-freebsd*
2059 Sanyo XStormy16 xstormy16-elf
2061 * OBSOLETE configurations and files
2063 Configurations that have been declared obsolete in this release have
2064 been commented out. Unless there is activity to revive these
2065 configurations, the next release of GDB will have their sources
2066 permanently REMOVED.
2068 AMD 29k family via UDI a29k-amd-udi, udi29k
2069 A29K VxWorks a29k-*-vxworks
2070 AMD 29000 embedded, using EBMON a29k-none-none
2071 AMD 29000 embedded with COFF a29k-none-coff
2072 AMD 29000 embedded with a.out a29k-none-aout
2074 testsuite/gdb.hp/gdb.threads-hp/ directory
2076 * REMOVED configurations and files
2078 TI TMS320C80 tic80-*-*
2080 PowerPC Solaris powerpcle-*-solaris*
2081 PowerPC Windows NT powerpcle-*-cygwin32
2082 PowerPC Netware powerpc-*-netware*
2083 Harris/CXUX m88k m88*-harris-cxux*
2084 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2085 ns32k-utek-sysv* ns32k-utek-*
2086 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2087 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2088 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2089 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2090 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2092 * Changes to command line processing
2094 The new `--args' feature can be used to specify command-line arguments
2095 for the inferior from gdb's command line.
2097 * Changes to key bindings
2099 There is a new `operate-and-get-next' function bound to `C-o'.
2101 *** Changes in GDB 5.1.1
2103 Fix compile problem on DJGPP.
2105 Fix a problem with floating-point registers on the i386 being
2108 Fix to stop GDB crashing on .debug_str debug info.
2110 Numerous documentation fixes.
2112 Numerous testsuite fixes.
2114 *** Changes in GDB 5.1:
2116 * New native configurations
2118 Alpha FreeBSD alpha*-*-freebsd*
2119 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2120 MIPS GNU/Linux mips*-*-linux*
2121 MIPS SGI Irix 6.x mips*-sgi-irix6*
2122 ia64 AIX ia64-*-aix*
2123 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2127 Motorola 68HC11 and 68HC12 m68hc11-elf
2129 UltraSparc running GNU/Linux sparc64-*-linux*
2131 * OBSOLETE configurations and files
2133 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2134 Harris/CXUX m88k m88*-harris-cxux*
2135 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2136 ns32k-utek-sysv* ns32k-utek-*
2137 TI TMS320C80 tic80-*-*
2139 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2140 PowerPC Solaris powerpcle-*-solaris*
2141 PowerPC Windows NT powerpcle-*-cygwin32
2142 PowerPC Netware powerpc-*-netware*
2143 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2144 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2145 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2146 Apple Macintosh (MPW) host N/A
2148 stuff.c (Program to stuff files into a specially prepared space in kdb)
2149 kdb-start.c (Main loop for the standalone kernel debugger)
2151 Configurations that have been declared obsolete in this release have
2152 been commented out. Unless there is activity to revive these
2153 configurations, the next release of GDB will have their sources
2154 permanently REMOVED.
2156 * REMOVED configurations and files
2158 Altos 3068 m68*-altos-*
2159 Convex c1-*-*, c2-*-*
2161 ARM RISCix arm-*-* (as host)
2165 * GDB has been converted to ISO C.
2167 GDB's source code has been converted to ISO C. In particular, the
2168 sources are fully protoized, and rely on standard headers being
2173 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2175 * The MI enabled by default.
2177 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2178 revised and enabled by default. Packages which use GDB as a debugging
2179 engine behind a UI or another front end are encouraged to switch to
2180 using the GDB/MI interface, instead of the old annotations interface
2181 which is now deprecated.
2183 * Support for debugging Pascal programs.
2185 GDB now includes support for debugging Pascal programs. The following
2186 main features are supported:
2188 - Pascal-specific data types such as sets;
2190 - automatic recognition of Pascal sources based on file-name
2193 - Pascal-style display of data types, variables, and functions;
2195 - a Pascal expression parser.
2197 However, some important features are not yet supported.
2199 - Pascal string operations are not supported at all;
2201 - there are some problems with boolean types;
2203 - Pascal type hexadecimal constants are not supported
2204 because they conflict with the internal variables format;
2206 - support for Pascal objects and classes is not full yet;
2208 - unlike Pascal, GDB is case-sensitive for symbol names.
2210 * Changes in completion.
2212 Commands such as `shell', `run' and `set args', which pass arguments
2213 to inferior programs, now complete on file names, similar to what
2214 users expect at the shell prompt.
2216 Commands which accept locations, such as `disassemble', `print',
2217 `breakpoint', `until', etc. now complete on filenames as well as
2218 program symbols. Thus, if you type "break foob TAB", and the source
2219 files linked into the programs include `foobar.c', that file name will
2220 be one of the candidates for completion. However, file names are not
2221 considered for completion after you typed a colon that delimits a file
2222 name from a name of a function in that file, as in "break foo.c:bar".
2224 `set demangle-style' completes on available demangling styles.
2226 * New platform-independent commands:
2228 It is now possible to define a post-hook for a command as well as a
2229 hook that runs before the command. For more details, see the
2230 documentation of `hookpost' in the GDB manual.
2232 * Changes in GNU/Linux native debugging.
2234 Support for debugging multi-threaded programs has been completely
2235 revised for all platforms except m68k and sparc. You can now debug as
2236 many threads as your system allows you to have.
2238 Attach/detach is supported for multi-threaded programs.
2240 Support for SSE registers was added for x86. This doesn't work for
2241 multi-threaded programs though.
2243 * Changes in MIPS configurations.
2245 Multi-arch support is enabled for all MIPS configurations.
2247 GDB can now be built as native debugger on SGI Irix 6.x systems for
2248 debugging n32 executables. (Debugging 64-bit executables is not yet
2251 * Unified support for hardware watchpoints in all x86 configurations.
2253 Most (if not all) native x86 configurations support hardware-assisted
2254 breakpoints and watchpoints in a unified manner. This support
2255 implements debug register sharing between watchpoints, which allows to
2256 put a virtually infinite number of watchpoints on the same address,
2257 and also supports watching regions up to 16 bytes with several debug
2260 The new maintenance command `maintenance show-debug-regs' toggles
2261 debugging print-outs in functions that insert, remove, and test
2262 watchpoints and hardware breakpoints.
2264 * Changes in the DJGPP native configuration.
2266 New command ``info dos sysinfo'' displays assorted information about
2267 the CPU, OS, memory, and DPMI server.
2269 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2270 display information about segment descriptors stored in GDT, LDT, and
2273 New commands ``info dos pde'' and ``info dos pte'' display entries
2274 from Page Directory and Page Tables (for now works with CWSDPMI only).
2275 New command ``info dos address-pte'' displays the Page Table entry for
2276 a given linear address.
2278 GDB can now pass command lines longer than 126 characters to the
2279 program being debugged (requires an update to the libdbg.a library
2280 which is part of the DJGPP development kit).
2282 DWARF2 debug info is now supported.
2284 It is now possible to `step' and `next' through calls to `longjmp'.
2286 * Changes in documentation.
2288 All GDB documentation was converted to GFDL, the GNU Free
2289 Documentation License.
2291 Tracepoints-related commands are now fully documented in the GDB
2294 TUI, the Text-mode User Interface, is now documented in the manual.
2296 Tracepoints-related commands are now fully documented in the GDB
2299 The "GDB Internals" manual now has an index. It also includes
2300 documentation of `ui_out' functions, GDB coding standards, x86
2301 hardware watchpoints, and memory region attributes.
2303 * GDB's version number moved to ``version.in''
2305 The Makefile variable VERSION has been replaced by the file
2306 ``version.in''. People creating GDB distributions should update the
2307 contents of this file.
2311 GUD support is now a standard part of the EMACS distribution.
2313 *** Changes in GDB 5.0:
2315 * Improved support for debugging FP programs on x86 targets
2317 Unified and much-improved support for debugging floating-point
2318 programs on all x86 targets. In particular, ``info float'' now
2319 displays the FP registers in the same format on all x86 targets, with
2320 greater level of detail.
2322 * Improvements and bugfixes in hardware-assisted watchpoints
2324 It is now possible to watch array elements, struct members, and
2325 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2326 on x86 targets no longer erroneously trigger when the address is
2329 * Improvements in the native DJGPP version of GDB
2331 The distribution now includes all the scripts and auxiliary files
2332 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2333 machines ``out of the box''.
2335 The DJGPP version can now debug programs that use signals. It is
2336 possible to catch signals that happened in the debuggee, deliver
2337 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2338 would kill the program being debugged.) Programs that hook hardware
2339 interrupts (keyboard, timer, etc.) can also be debugged.
2341 It is now possible to debug DJGPP programs that redirect their
2342 standard handles or switch them to raw (as opposed to cooked) mode, or
2343 even close them. The command ``run < foo > bar'' works as expected,
2344 and ``info terminal'' reports useful information about the debuggee's
2345 terminal, including raw/cooked mode, redirection, etc.
2347 The DJGPP version now uses termios functions for console I/O, which
2348 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2351 DOS-style file names with drive letters are now fully supported by
2354 It is now possible to debug DJGPP programs that switch their working
2355 directory. It is also possible to rerun the debuggee any number of
2356 times without restarting GDB; thus, you can use the same setup,
2357 breakpoints, etc. for many debugging sessions.
2359 * New native configurations
2361 ARM GNU/Linux arm*-*-linux*
2362 PowerPC GNU/Linux powerpc-*-linux*
2366 Motorola MCore mcore-*-*
2367 x86 VxWorks i[3456]86-*-vxworks*
2368 PowerPC VxWorks powerpc-*-vxworks*
2369 TI TMS320C80 tic80-*-*
2371 * OBSOLETE configurations
2373 Altos 3068 m68*-altos-*
2374 Convex c1-*-*, c2-*-*
2376 ARM RISCix arm-*-* (as host)
2379 Configurations that have been declared obsolete will be commented out,
2380 but the code will be left in place. If there is no activity to revive
2381 these configurations before the next release of GDB, the sources will
2382 be permanently REMOVED.
2384 * Gould support removed
2386 Support for the Gould PowerNode and NP1 has been removed.
2388 * New features for SVR4
2390 On SVR4 native platforms (such as Solaris), if you attach to a process
2391 without first loading a symbol file, GDB will now attempt to locate and
2392 load symbols from the running process's executable file.
2394 * Many C++ enhancements
2396 C++ support has been greatly improved. Overload resolution now works properly
2397 in almost all cases. RTTI support is on the way.
2399 * Remote targets can connect to a sub-program
2401 A popen(3) style serial-device has been added. This device starts a
2402 sub-process (such as a stand-alone simulator) and then communicates
2403 with that. The sub-program to run is specified using the syntax
2404 ``|<program> <args>'' vis:
2406 (gdb) set remotedebug 1
2407 (gdb) target extended-remote |mn10300-elf-sim program-args
2409 * MIPS 64 remote protocol
2411 A long standing bug in the mips64 remote protocol where by GDB
2412 expected certain 32 bit registers (ex SR) to be transfered as 32
2413 instead of 64 bits has been fixed.
2415 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2416 added to provide backward compatibility with older versions of GDB.
2418 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2420 The command ``set remotebinarydownload'' command has been replaced by
2421 ``set remote X-packet''. Other commands in ``set remote'' family
2422 include ``set remote P-packet''.
2424 * Breakpoint commands accept ranges.
2426 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2427 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2428 ``tracepoint passcount'' also accepts a range of tracepoints.
2430 * ``apropos'' command added.
2432 The ``apropos'' command searches through command names and
2433 documentation strings, printing out matches, making it much easier to
2434 try to find a command that does what you are looking for.
2438 A new machine oriented interface (MI) has been added to GDB. This
2439 interface is designed for debug environments running GDB as a separate
2440 process. This is part of the long term libGDB project. See the
2441 "GDB/MI" chapter of the GDB manual for further information. It can be
2442 enabled by configuring with:
2444 .../configure --enable-gdbmi
2446 *** Changes in GDB-4.18:
2448 * New native configurations
2450 HP-UX 10.20 hppa*-*-hpux10.20
2451 HP-UX 11.x hppa*-*-hpux11.0*
2452 M68K GNU/Linux m68*-*-linux*
2456 Fujitsu FR30 fr30-*-elf*
2457 Intel StrongARM strongarm-*-*
2458 Mitsubishi D30V d30v-*-*
2460 * OBSOLETE configurations
2462 Gould PowerNode, NP1 np1-*-*, pn-*-*
2464 Configurations that have been declared obsolete will be commented out,
2465 but the code will be left in place. If there is no activity to revive
2466 these configurations before the next release of GDB, the sources will
2467 be permanently REMOVED.
2471 As a compatibility experiment, GDB's source files buildsym.h and
2472 buildsym.c have been converted to pure standard C, no longer
2473 containing any K&R compatibility code. We believe that all systems in
2474 use today either come with a standard C compiler, or have a GCC port
2475 available. If this is not true, please report the affected
2476 configuration to bug-gdb@gnu.org immediately. See the README file for
2477 information about getting a standard C compiler if you don't have one
2482 GDB now uses readline 2.2.
2484 * set extension-language
2486 You can now control the mapping between filename extensions and source
2487 languages by using the `set extension-language' command. For instance,
2488 you can ask GDB to treat .c files as C++ by saying
2489 set extension-language .c c++
2490 The command `info extensions' lists all of the recognized extensions
2491 and their associated languages.
2493 * Setting processor type for PowerPC and RS/6000
2495 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2496 you can use the `set processor' command to specify what variant of the
2497 PowerPC family you are debugging. The command
2501 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2502 following PowerPC and RS6000 variants:
2504 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2505 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2507 403GC IBM PowerPC 403GC
2508 505 Motorola PowerPC 505
2509 860 Motorola PowerPC 860 or 850
2510 601 Motorola PowerPC 601
2511 602 Motorola PowerPC 602
2512 603 Motorola/IBM PowerPC 603 or 603e
2513 604 Motorola PowerPC 604 or 604e
2514 750 Motorola/IBM PowerPC 750 or 750
2516 At the moment, this command just tells GDB what to name the
2517 special-purpose processor registers. Since almost all the affected
2518 registers are inaccessible to user-level programs, this command is
2519 only useful for remote debugging in its present form.
2523 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2524 more extensive support for HP-UX. Added features include shared
2525 library support, kernel threads and hardware watchpoints for 11.00,
2526 support for HP's ANSI C and C++ compilers, and a compatibility mode
2527 for xdb and dbx commands.
2531 HP's donation includes the new concept of catchpoints, which is a
2532 generalization of the old catch command. On HP-UX, it is now possible
2533 to catch exec, fork, and vfork, as well as library loading.
2535 This means that the existing catch command has changed; its first
2536 argument now specifies the type of catch to be set up. See the
2537 output of "help catch" for a list of catchpoint types.
2539 * Debugging across forks
2541 On HP-UX, you can choose which process to debug when a fork() happens
2546 HP has donated a curses-based terminal user interface (TUI). To get
2547 it, build with --enable-tui. Although this can be enabled for any
2548 configuration, at present it only works for native HP debugging.
2550 * GDB remote protocol additions
2552 A new protocol packet 'X' that writes binary data is now available.
2553 Default behavior is to try 'X', then drop back to 'M' if the stub
2554 fails to respond. The settable variable `remotebinarydownload'
2555 allows explicit control over the use of 'X'.
2557 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2558 full 64-bit address. The command
2560 set remoteaddresssize 32
2562 can be used to revert to the old behaviour. For existing remote stubs
2563 the change should not be noticed, as the additional address information
2566 In order to assist in debugging stubs, you may use the maintenance
2567 command `packet' to send any text string to the stub. For instance,
2569 maint packet heythere
2571 sends the packet "$heythere#<checksum>". Note that it is very easy to
2572 disrupt a debugging session by sending the wrong packet at the wrong
2575 The compare-sections command allows you to compare section data on the
2576 target to what is in the executable file without uploading or
2577 downloading, by comparing CRC checksums.
2579 * Tracing can collect general expressions
2581 You may now collect general expressions at tracepoints. This requires
2582 further additions to the target-side stub; see tracepoint.c and
2583 doc/agentexpr.texi for further details.
2585 * mask-address variable for Mips
2587 For Mips targets, you may control the zeroing of the upper 32 bits of
2588 a 64-bit address by entering `set mask-address on'. This is mainly
2589 of interest to users of embedded R4xxx and R5xxx processors.
2591 * Higher serial baud rates
2593 GDB's serial code now allows you to specify baud rates 57600, 115200,
2594 230400, and 460800 baud. (Note that your host system may not be able
2595 to achieve all of these rates.)
2599 The i960 configuration now includes an initial implementation of a
2600 builtin simulator, contributed by Jim Wilson.
2603 *** Changes in GDB-4.17:
2605 * New native configurations
2607 Alpha GNU/Linux alpha*-*-linux*
2608 Unixware 2.x i[3456]86-unixware2*
2609 Irix 6.x mips*-sgi-irix6*
2610 PowerPC GNU/Linux powerpc-*-linux*
2611 PowerPC Solaris powerpcle-*-solaris*
2612 Sparc GNU/Linux sparc-*-linux*
2613 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2617 Argonaut Risc Chip (ARC) arc-*-*
2618 Hitachi H8/300S h8300*-*-*
2619 Matsushita MN10200 w/simulator mn10200-*-*
2620 Matsushita MN10300 w/simulator mn10300-*-*
2621 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2622 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2623 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2624 Mitsubishi D10V w/simulator d10v-*-*
2625 Mitsubishi M32R/D w/simulator m32r-*-elf*
2626 Tsqware Sparclet sparclet-*-*
2627 NEC V850 w/simulator v850-*-*
2629 * New debugging protocols
2631 ARM with RDI protocol arm*-*-*
2632 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2633 DDB and LSI variants of PMON protocol mips*-*-*
2634 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2635 PowerPC with SDS protocol powerpc{,le}-*-eabi
2636 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2640 All configurations can now understand and use the DWARF 2 debugging
2641 format. The choice is automatic, if the symbol file contains DWARF 2
2646 GDB now includes basic Java language support. This support is
2647 only useful with Java compilers that produce native machine code.
2649 * solib-absolute-prefix and solib-search-path
2651 For SunOS and SVR4 shared libraries, you may now set the prefix for
2652 loading absolute shared library symbol files, and the search path for
2653 locating non-absolute shared library symbol files.
2655 * Live range splitting
2657 GDB can now effectively debug code for which GCC has performed live
2658 range splitting as part of its optimization. See gdb/doc/LRS for
2659 more details on the expected format of the stabs information.
2663 GDB's support for the GNU Hurd, including thread debugging, has been
2664 updated to work with current versions of the Hurd.
2668 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2669 instruction set. ARM GDB automatically detects when Thumb
2670 instructions are in use, and adjusts disassembly and backtracing
2675 GDB's MIPS target configurations now handle the MIP16 16-bit
2680 GDB now includes support for overlays; if an executable has been
2681 linked such that multiple sections are based at the same address, GDB
2682 will decide which section to use for symbolic info. You can choose to
2683 control the decision manually, using overlay commands, or implement
2684 additional target-side support and use "overlay load-target" to bring
2685 in the overlay mapping. Do "help overlay" for more detail.
2689 The command "info symbol <address>" displays information about
2690 the symbol at the specified address.
2694 The standard remote protocol now includes an extension that allows
2695 asynchronous collection and display of trace data. This requires
2696 extensive support in the target-side debugging stub. Tracing mode
2697 includes a new interaction mode in GDB and new commands: see the
2698 file tracepoint.c for more details.
2702 Configurations for embedded MIPS now include a simulator contributed
2703 by Cygnus Solutions. The simulator supports the instruction sets
2704 of most MIPS variants.
2708 Sparc configurations may now include the ERC32 simulator contributed
2709 by the European Space Agency. The simulator is not built into
2710 Sparc targets by default; configure with --enable-sim to include it.
2714 For target configurations that may include multiple variants of a
2715 basic architecture (such as MIPS and SH), you may now set the
2716 architecture explicitly. "set arch" sets, "info arch" lists
2717 the possible architectures.
2719 *** Changes in GDB-4.16:
2721 * New native configurations
2723 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2724 M68K NetBSD m68k-*-netbsd*
2725 PowerPC AIX 4.x powerpc-*-aix*
2726 PowerPC MacOS powerpc-*-macos*
2727 PowerPC Windows NT powerpcle-*-cygwin32
2728 RS/6000 AIX 4.x rs6000-*-aix4*
2732 ARM with RDP protocol arm-*-*
2733 I960 with MON960 i960-*-coff
2734 MIPS VxWorks mips*-*-vxworks*
2735 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2736 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2738 Matra Sparclet sparclet-*-*
2742 The powerpc-eabi configuration now includes the PSIM simulator,
2743 contributed by Andrew Cagney, with assistance from Mike Meissner.
2744 PSIM is a very elaborate model of the PowerPC, including not only
2745 basic instruction set execution, but also details of execution unit
2746 performance and I/O hardware. See sim/ppc/README for more details.
2750 GDB now works with Solaris 2.5.
2752 * Windows 95/NT native
2754 GDB will now work as a native debugger on Windows 95 and Windows NT.
2755 To build it from source, you must use the "gnu-win32" environment,
2756 which uses a DLL to emulate enough of Unix to run the GNU tools.
2757 Further information, binaries, and sources are available at
2758 ftp.cygnus.com, under pub/gnu-win32.
2760 * dont-repeat command
2762 If a user-defined command includes the command `dont-repeat', then the
2763 command will not be repeated if the user just types return. This is
2764 useful if the command is time-consuming to run, so that accidental
2765 extra keystrokes don't run the same command many times.
2767 * Send break instead of ^C
2769 The standard remote protocol now includes an option to send a break
2770 rather than a ^C to the target in order to interrupt it. By default,
2771 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2773 * Remote protocol timeout
2775 The standard remote protocol includes a new variable `remotetimeout'
2776 that allows you to set the number of seconds before GDB gives up trying
2777 to read from the target. The default value is 2.
2779 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2781 By default GDB will automatically keep track of objects as they are
2782 loaded and unloaded by the dynamic linker. By using the command `set
2783 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2784 when shared library events occur, thus allowing you to set breakpoints
2785 in shared libraries which are explicitly loaded by the inferior.
2787 Note this feature does not work on hpux8. On hpux9 you must link
2788 /usr/lib/end.o into your program. This feature should work
2789 automatically on hpux10.
2791 * Irix 5.x hardware watchpoint support
2793 Irix 5 configurations now support the use of hardware watchpoints.
2795 * Mips protocol "SYN garbage limit"
2797 When debugging a Mips target using the `target mips' protocol, you
2798 may set the number of characters that GDB will ignore by setting
2799 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2800 every character. The default value is 1050.
2802 * Recording and replaying remote debug sessions
2804 If you set `remotelogfile' to the name of a file, gdb will write to it
2805 a recording of a remote debug session. This recording may then be
2806 replayed back to gdb using "gdbreplay". See gdbserver/README for
2807 details. This is useful when you have a problem with GDB while doing
2808 remote debugging; you can make a recording of the session and send it
2809 to someone else, who can then recreate the problem.
2811 * Speedups for remote debugging
2813 GDB includes speedups for downloading and stepping MIPS systems using
2814 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2815 and more efficient S-record downloading.
2817 * Memory use reductions and statistics collection
2819 GDB now uses less memory and reports statistics about memory usage.
2820 Try the `maint print statistics' command, for example.
2822 *** Changes in GDB-4.15:
2824 * Psymtabs for XCOFF
2826 The symbol reader for AIX GDB now uses partial symbol tables. This
2827 can greatly improve startup time, especially for large executables.
2829 * Remote targets use caching
2831 Remote targets now use a data cache to speed up communication with the
2832 remote side. The data cache could lead to incorrect results because
2833 it doesn't know about volatile variables, thus making it impossible to
2834 debug targets which use memory mapped I/O devices. `set remotecache
2835 off' turns the the data cache off.
2837 * Remote targets may have threads
2839 The standard remote protocol now includes support for multiple threads
2840 in the target system, using new protocol commands 'H' and 'T'. See
2841 gdb/remote.c for details.
2845 If GDB is configured with `--enable-netrom', then it will include
2846 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2847 acts as though it is a bank of ROM on the target board, but you can
2848 write into it over the network. GDB's support consists only of
2849 support for fast loading into the emulated ROM; to debug, you must use
2850 another protocol, such as standard remote protocol. The usual
2851 sequence is something like
2853 target nrom <netrom-hostname>
2855 target remote <netrom-hostname>:1235
2859 GDB now includes support for the Apple Macintosh, as a host only. It
2860 may be run as either an MPW tool or as a standalone application, and
2861 it can debug through the serial port. All the usual GDB commands are
2862 available, but to the target command, you must supply "serial" as the
2863 device type instead of "/dev/ttyXX". See mpw-README in the main
2864 directory for more information on how to build. The MPW configuration
2865 scripts */mpw-config.in support only a few targets, and only the
2866 mips-idt-ecoff target has been tested.
2870 GDB configuration now uses autoconf. This is not user-visible,
2871 but does simplify configuration and building.
2875 GDB now supports hpux10.
2877 *** Changes in GDB-4.14:
2879 * New native configurations
2881 x86 FreeBSD i[345]86-*-freebsd
2882 x86 NetBSD i[345]86-*-netbsd
2883 NS32k NetBSD ns32k-*-netbsd
2884 Sparc NetBSD sparc-*-netbsd
2888 A29K VxWorks a29k-*-vxworks
2889 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2890 CPU32 EST-300 emulator m68*-*-est*
2891 PowerPC ELF powerpc-*-elf
2894 * Alpha OSF/1 support for procfs
2896 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2897 possible to attach to running processes. As the mounting of the /proc
2898 filesystem is optional on the Alpha, GDB automatically determines
2899 the availability of /proc during startup. This can lead to problems
2900 if /proc is unmounted after GDB has been started.
2902 * Arguments to user-defined commands
2904 User commands may accept up to 10 arguments separated by whitespace.
2905 Arguments are accessed within the user command via $arg0..$arg9. A
2908 print $arg0 + $arg1 + $arg2
2910 To execute the command use:
2913 Defines the command "adder" which prints the sum of its three arguments.
2914 Note the arguments are text substitutions, so they may reference variables,
2915 use complex expressions, or even perform inferior function calls.
2917 * New `if' and `while' commands
2919 This makes it possible to write more sophisticated user-defined
2920 commands. Both commands take a single argument, which is the
2921 expression to evaluate, and must be followed by the commands to
2922 execute, one per line, if the expression is nonzero, the list being
2923 terminated by the word `end'. The `if' command list may include an
2924 `else' word, which causes the following commands to be executed only
2925 if the expression is zero.
2927 * Fortran source language mode
2929 GDB now includes partial support for Fortran 77. It will recognize
2930 Fortran programs and can evaluate a subset of Fortran expressions, but
2931 variables and functions may not be handled correctly. GDB will work
2932 with G77, but does not yet know much about symbols emitted by other
2935 * Better HPUX support
2937 Most debugging facilities now work on dynamic executables for HPPAs
2938 running hpux9 or later. You can attach to running dynamically linked
2939 processes, but by default the dynamic libraries will be read-only, so
2940 for instance you won't be able to put breakpoints in them. To change
2941 that behavior do the following before running the program:
2947 This will cause the libraries to be mapped private and read-write.
2948 To revert to the normal behavior, do this:
2954 You cannot set breakpoints or examine data in the library until after
2955 the library is loaded if the function/data symbols do not have
2958 GDB can now also read debug symbols produced by the HP C compiler on
2959 HPPAs (sorry, no C++, Fortran or 68k support).
2961 * Target byte order now dynamically selectable
2963 You can choose which byte order to use with a target system, via the
2964 commands "set endian big" and "set endian little", and you can see the
2965 current setting by using "show endian". You can also give the command
2966 "set endian auto", in which case GDB will use the byte order
2967 associated with the executable. Currently, only embedded MIPS
2968 configurations support dynamic selection of target byte order.
2970 * New DOS host serial code
2972 This version uses DPMI interrupts to handle buffered I/O, so you
2973 no longer need to run asynctsr when debugging boards connected to
2976 *** Changes in GDB-4.13:
2978 * New "complete" command
2980 This lists all the possible completions for the rest of the line, if it
2981 were to be given as a command itself. This is intended for use by emacs.
2983 * Trailing space optional in prompt
2985 "set prompt" no longer adds a space for you after the prompt you set. This
2986 allows you to set a prompt which ends in a space or one that does not.
2988 * Breakpoint hit counts
2990 "info break" now displays a count of the number of times the breakpoint
2991 has been hit. This is especially useful in conjunction with "ignore"; you
2992 can ignore a large number of breakpoint hits, look at the breakpoint info
2993 to see how many times the breakpoint was hit, then run again, ignoring one
2994 less than that number, and this will get you quickly to the last hit of
2997 * Ability to stop printing at NULL character
2999 "set print null-stop" will cause GDB to stop printing the characters of
3000 an array when the first NULL is encountered. This is useful when large
3001 arrays actually contain only short strings.
3003 * Shared library breakpoints
3005 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3006 breakpoints in shared libraries before the executable is run.
3008 * Hardware watchpoints
3010 There is a new hardware breakpoint for the watch command for sparclite
3011 targets. See gdb/sparclite/hw_breakpoint.note.
3013 Hardware watchpoints are also now supported under GNU/Linux.
3017 Annotations have been added. These are for use with graphical interfaces,
3018 and are still experimental. Currently only gdba.el uses these.
3020 * Improved Irix 5 support
3022 GDB now works properly with Irix 5.2.
3024 * Improved HPPA support
3026 GDB now works properly with the latest GCC and GAS.
3028 * New native configurations
3030 Sequent PTX4 i[34]86-sequent-ptx4
3031 HPPA running OSF/1 hppa*-*-osf*
3032 Atari TT running SVR4 m68*-*-sysv4*
3033 RS/6000 LynxOS rs6000-*-lynxos*
3037 OS/9000 i[34]86-*-os9k
3038 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3041 * Hitachi SH7000 and E7000-PC ICE support
3043 There is now support for communicating with the Hitachi E7000-PC ICE.
3044 This is available automatically when GDB is configured for the SH.
3048 As usual, a variety of small fixes and improvements, both generic
3049 and configuration-specific. See the ChangeLog for more detail.
3051 *** Changes in GDB-4.12:
3053 * Irix 5 is now supported
3057 GDB-4.12 on the HPPA has a number of changes which make it unable
3058 to debug the output from the currently released versions of GCC and
3059 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3060 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3061 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3064 *** Changes in GDB-4.11:
3066 * User visible changes:
3070 The "set remotedebug" option is now consistent between the mips remote
3071 target, remote targets using the gdb-specific protocol, UDI (AMD's
3072 debug protocol for the 29k) and the 88k bug monitor. It is now an
3073 integer specifying a debug level (normally 0 or 1, but 2 means more
3074 debugging info for the mips target).
3076 * DEC Alpha native support
3078 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3079 debug info, but GDB works fairly well with the DEC compiler and should
3080 work with a future GCC release. See the README file for a few
3081 Alpha-specific notes.
3083 * Preliminary thread implementation
3085 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3087 * LynxOS native and target support for 386
3089 This release has been hosted on LynxOS 2.2, and also can be configured
3090 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3093 * Improvements in C++ mangling/demangling.
3095 This release has much better g++ debugging, specifically in name
3096 mangling/demangling, virtual function calls, print virtual table,
3097 call methods, ...etc.
3099 *** Changes in GDB-4.10:
3101 * User visible changes:
3103 Remote debugging using the GDB-specific (`target remote') protocol now
3104 supports the `load' command. This is only useful if you have some
3105 other way of getting the stub to the target system, and you can put it
3106 somewhere in memory where it won't get clobbered by the download.
3108 Filename completion now works.
3110 When run under emacs mode, the "info line" command now causes the
3111 arrow to point to the line specified. Also, "info line" prints
3112 addresses in symbolic form (as well as hex).
3114 All vxworks based targets now support a user settable option, called
3115 vxworks-timeout. This option represents the number of seconds gdb
3116 should wait for responses to rpc's. You might want to use this if
3117 your vxworks target is, perhaps, a slow software simulator or happens
3118 to be on the far side of a thin network line.
3122 This release contains support for using a DEC alpha as a GDB host for
3123 cross debugging. Native alpha debugging is not supported yet.
3126 *** Changes in GDB-4.9:
3130 This is the first GDB release which is accompanied by a matching testsuite.
3131 The testsuite requires installation of dejagnu, which should be available
3132 via ftp from most sites that carry GNU software.
3136 'Cfront' style demangling has had its name changed to 'ARM' style, to
3137 emphasize that it was written from the specifications in the C++ Annotated
3138 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3139 disclaimers, it still generated too much confusion with users attempting to
3140 use gdb with AT&T cfront.
3144 GDB now uses a standard remote interface to a simulator library.
3145 So far, the library contains simulators for the Zilog Z8001/2, the
3146 Hitachi H8/300, H8/500 and Super-H.
3148 * New targets supported
3150 H8/300 simulator h8300-hitachi-hms or h8300hms
3151 H8/500 simulator h8500-hitachi-hms or h8500hms
3152 SH simulator sh-hitachi-hms or sh
3153 Z8000 simulator z8k-zilog-none or z8ksim
3154 IDT MIPS board over serial line mips-idt-ecoff
3156 Cross-debugging to GO32 targets is supported. It requires a custom
3157 version of the i386-stub.c module which is integrated with the
3158 GO32 memory extender.
3160 * New remote protocols
3162 MIPS remote debugging protocol.
3164 * New source languages supported
3166 This version includes preliminary support for Chill, a Pascal like language
3167 used by telecommunications companies. Chill support is also being integrated
3168 into the GNU compiler, but we don't know when it will be publically available.
3171 *** Changes in GDB-4.8:
3173 * HP Precision Architecture supported
3175 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3176 version of this support was available as a set of patches from the
3177 University of Utah. GDB does not support debugging of programs
3178 compiled with the HP compiler, because HP will not document their file
3179 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3180 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3182 Many problems in the preliminary version have been fixed.
3184 * Faster and better demangling
3186 We have improved template demangling and fixed numerous bugs in the GNU style
3187 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3188 character types (wchar_t) are now supported. Demangling of each symbol is now
3189 only done once, and is cached when the symbol table for a file is read in.
3190 This results in a small increase in memory usage for C programs, a moderate
3191 increase in memory usage for C++ programs, and a fantastic speedup in
3194 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3195 from the specifications in the Annotated Reference Manual, which AT&T's
3196 compiler does not actually implement.
3198 * G++ multiple inheritance compiler problem
3200 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3201 inheritance lattices was reworked to properly discover ambiguities. We
3202 recently found an example which causes this new algorithm to fail in a
3203 very subtle way, producing bad debug information for those classes.
3204 The file 'gcc.patch' (in this directory) can be applied to gcc to
3205 circumvent the problem. A future GCC release will contain a complete
3208 The previous G++ debug info problem (mentioned below for the gdb-4.7
3209 release) is fixed in gcc version 2.3.2.
3211 * Improved configure script
3213 The `configure' script will now attempt to guess your system type if
3214 you don't supply a host system type. The old scheme of supplying a
3215 host system triplet is preferable over using this. All the magic is
3216 done in the new `config.guess' script. Examine it for details.
3218 We have also brought our configure script much more in line with the FSF's
3219 version. It now supports the --with-xxx options. In particular,
3220 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3221 The resulting GDB will not be able to read arbitrary object file formats --
3222 only the format ``expected'' to be used on the configured target system.
3223 We hope to make this the default in a future release.
3225 * Documentation improvements
3227 There's new internal documentation on how to modify GDB, and how to
3228 produce clean changes to the code. We implore people to read it
3229 before submitting changes.
3231 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3232 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3233 `info' files are also provided. To build `info' files from scratch,
3234 you will need the latest `makeinfo' release, which will be available in
3235 a future texinfo-X.Y release.
3237 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3238 We're not sure exactly which versions have this problem, but it has
3239 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3240 or better. If that isn't possible, there is a patch in
3241 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3242 around this problem.
3246 GDB now supports array constants that can be used in expressions typed in by
3247 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3248 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3251 The new directory `gdb/sparclite' contains a program that demonstrates
3252 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3254 * New native hosts supported
3256 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3257 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3259 * New targets supported
3261 AMD 29k family via UDI a29k-amd-udi or udi29k
3263 * New file formats supported
3265 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3266 HPUX core files, and SCO 3.2v2 core files.
3270 Attaching to processes now works again; thanks for the many bug reports.
3272 We have also stomped on a bunch of core dumps caused by
3273 printf_filtered("%s") problems.
3275 We eliminated a copyright problem on the rpc and ptrace header files
3276 for VxWorks, which was discovered at the last minute during the 4.7
3277 release. You should now be able to build a VxWorks GDB.
3279 You can now interrupt gdb while an attached process is running. This
3280 will cause the attached process to stop, and give control back to GDB.
3282 We fixed problems caused by using too many file descriptors
3283 for reading symbols from object files and libraries. This was
3284 especially a problem for programs that used many (~100) shared
3287 The `step' command now only enters a subroutine if there is line number
3288 information for the subroutine. Otherwise it acts like the `next'
3289 command. Previously, `step' would enter subroutines if there was
3290 any debugging information about the routine. This avoids problems
3291 when using `cc -g1' on MIPS machines.
3293 * Internal improvements
3295 GDB's internal interfaces have been improved to make it easier to support
3296 debugging of multiple languages in the future.
3298 GDB now uses a common structure for symbol information internally.
3299 Minimal symbols (derived from linkage symbols in object files), partial
3300 symbols (from a quick scan of debug information), and full symbols
3301 contain a common subset of information, making it easier to write
3302 shared code that handles any of them.
3304 * New command line options
3306 We now accept --silent as an alias for --quiet.
3310 The memory-mapped-malloc library is now licensed under the GNU Library
3311 General Public License.
3313 *** Changes in GDB-4.7:
3315 * Host/native/target split
3317 GDB has had some major internal surgery to untangle the support for
3318 hosts and remote targets. Now, when you configure GDB for a remote
3319 target, it will no longer load in all of the support for debugging
3320 local programs on the host. When fully completed and tested, this will
3321 ensure that arbitrary host/target combinations are possible.
3323 The primary conceptual shift is to separate the non-portable code in
3324 GDB into three categories. Host specific code is required any time GDB
3325 is compiled on that host, regardless of the target. Target specific
3326 code relates to the peculiarities of the target, but can be compiled on
3327 any host. Native specific code is everything else: it can only be
3328 built when the host and target are the same system. Child process
3329 handling and core file support are two common `native' examples.
3331 GDB's use of /proc for controlling Unix child processes is now cleaner.
3332 It has been split out into a single module under the `target_ops' vector,
3333 plus two native-dependent functions for each system that uses /proc.
3335 * New hosts supported
3337 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3338 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3339 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3341 * New targets supported
3343 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3344 68030 and CPU32 m68030-*-*, m68332-*-*
3346 * New native hosts supported
3348 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3349 (386bsd is not well tested yet)
3350 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3352 * New file formats supported
3354 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3355 supports reading of `a.out.adobe' object files, which are an a.out
3356 format extended with minimal information about multiple sections.
3360 `show copying' is the same as the old `info copying'.
3361 `show warranty' is the same as `info warrantee'.
3362 These were renamed for consistency. The old commands continue to work.
3364 `info handle' is a new alias for `info signals'.
3366 You can now define pre-command hooks, which attach arbitrary command
3367 scripts to any command. The commands in the hook will be executed
3368 prior to the user's command. You can also create a hook which will be
3369 executed whenever the program stops. See gdb.texinfo.
3373 We now deal with Cfront style name mangling, and can even extract type
3374 info from mangled symbols. GDB can automatically figure out which
3375 symbol mangling style your C++ compiler uses.
3377 Calling of methods and virtual functions has been improved as well.
3381 The crash that occured when debugging Sun Ansi-C compiled binaries is
3382 fixed. This was due to mishandling of the extra N_SO stabs output
3385 We also finally got Ultrix 4.2 running in house, and fixed core file
3386 support, with help from a dozen people on the net.
3388 John M. Farrell discovered that the reason that single-stepping was so
3389 slow on all of the Mips based platforms (primarily SGI and DEC) was
3390 that we were trying to demangle and lookup a symbol used for internal
3391 purposes on every instruction that was being stepped through. Changing
3392 the name of that symbol so that it couldn't be mistaken for a C++
3393 mangled symbol sped things up a great deal.
3395 Rich Pixley sped up symbol lookups in general by getting much smarter
3396 about when C++ symbol mangling is necessary. This should make symbol
3397 completion (TAB on the command line) much faster. It's not as fast as
3398 we'd like, but it's significantly faster than gdb-4.6.
3402 A new user controllable variable 'call_scratch_address' can
3403 specify the location of a scratch area to be used when GDB
3404 calls a function in the target. This is necessary because the
3405 usual method of putting the scratch area on the stack does not work
3406 in systems that have separate instruction and data spaces.
3408 We integrated changes to support the 29k UDI (Universal Debugger
3409 Interface), but discovered at the last minute that we didn't have all
3410 of the appropriate copyright paperwork. We are working with AMD to
3411 resolve this, and hope to have it available soon.
3415 We have sped up the remote serial line protocol, especially for targets
3416 with lots of registers. It now supports a new `expedited status' ('T')
3417 message which can be used in place of the existing 'S' status message.
3418 This allows the remote stub to send only the registers that GDB
3419 needs to make a quick decision about single-stepping or conditional
3420 breakpoints, eliminating the need to fetch the entire register set for
3421 each instruction being stepped through.
3423 The GDB remote serial protocol now implements a write-through cache for
3424 registers, only re-reading the registers if the target has run.
3426 There is also a new remote serial stub for SPARC processors. You can
3427 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3428 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3429 processor with a serial port.
3433 Configure.in files have become much easier to read and modify. A new
3434 `table driven' format makes it more obvious what configurations are
3435 supported, and what files each one uses.
3439 There is a new opcodes library which will eventually contain all of the
3440 disassembly routines and opcode tables. At present, it only contains
3441 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3442 disassembler (binutils/objdump) to share these routines.
3444 The libiberty library is now copylefted under the GNU Library General
3445 Public License. This allows more liberal use, and was done so libg++
3446 can use it. This makes no difference to GDB, since the Library License
3447 grants all the rights from the General Public License.
3451 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3452 reference to the stabs symbol info used by the debugger. It is (as far
3453 as we know) the only published document on this fascinating topic. We
3454 encourage you to read it, compare it to the stabs information on your
3455 system, and send improvements on the document in general (to
3456 bug-gdb@prep.ai.mit.edu).
3458 And, of course, many bugs have been fixed.
3461 *** Changes in GDB-4.6:
3463 * Better support for C++ function names
3465 GDB now accepts as input the "demangled form" of C++ overloaded function
3466 names and member function names, and can do command completion on such names
3467 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3468 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3469 Make use of command completion, it is your friend.
3471 GDB also now accepts a variety of C++ mangled symbol formats. They are
3472 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3473 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3474 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3475 for the list of formats.
3477 * G++ symbol mangling problem
3479 Recent versions of gcc have a bug in how they emit debugging information for
3480 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3481 directory) can be applied to gcc to fix the problem. Alternatively, if you
3482 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3483 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3484 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3487 * New 'maintenance' command
3489 All of the commands related to hacking GDB internals have been moved out of
3490 the main command set, and now live behind the 'maintenance' command. This
3491 can also be abbreviated as 'mt'. The following changes were made:
3493 dump-me -> maintenance dump-me
3494 info all-breakpoints -> maintenance info breakpoints
3495 printmsyms -> maintenance print msyms
3496 printobjfiles -> maintenance print objfiles
3497 printpsyms -> maintenance print psymbols
3498 printsyms -> maintenance print symbols
3500 The following commands are new:
3502 maintenance demangle Call internal GDB demangler routine to
3503 demangle a C++ link name and prints the result.
3504 maintenance print type Print a type chain for a given symbol
3506 * Change to .gdbinit file processing
3508 We now read the $HOME/.gdbinit file before processing the argv arguments
3509 (e.g. reading symbol files or core files). This allows global parameters to
3510 be set, which will apply during the symbol reading. The ./.gdbinit is still
3511 read after argv processing.
3513 * New hosts supported
3515 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3517 GNU/Linux support i386-unknown-linux or linux
3519 We are also including code to support the HP/PA running BSD and HPUX. This
3520 is almost guaranteed not to work, as we didn't have time to test or build it
3521 for this release. We are including it so that the more adventurous (or
3522 masochistic) of you can play with it. We also had major problems with the
3523 fact that the compiler that we got from HP doesn't support the -g option.
3526 * New targets supported
3528 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3530 * More smarts about finding #include files
3532 GDB now remembers the compilation directory for all include files, and for
3533 all files from which C is generated (like yacc and lex sources). This
3534 greatly improves GDB's ability to find yacc/lex sources, and include files,
3535 especially if you are debugging your program from a directory different from
3536 the one that contains your sources.
3538 We also fixed a bug which caused difficulty with listing and setting
3539 breakpoints in include files which contain C code. (In the past, you had to
3540 try twice in order to list an include file that you hadn't looked at before.)
3542 * Interesting infernals change
3544 GDB now deals with arbitrary numbers of sections, where the symbols for each
3545 section must be relocated relative to that section's landing place in the
3546 target's address space. This work was needed to support ELF with embedded
3547 stabs used by Solaris-2.0.
3549 * Bug fixes (of course!)
3551 There have been loads of fixes for the following things:
3552 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3553 i960, stabs, DOS(GO32), procfs, etc...
3555 See the ChangeLog for details.
3557 *** Changes in GDB-4.5:
3559 * New machines supported (host and target)
3561 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3563 SGI Irix-4.x mips-sgi-irix4 or iris4
3565 * New malloc package
3567 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3568 Mmalloc is capable of handling mutiple heaps of memory. It is also
3569 capable of saving a heap to a file, and then mapping it back in later.
3570 This can be used to greatly speedup the startup of GDB by using a
3571 pre-parsed symbol table which lives in a mmalloc managed heap. For
3572 more details, please read mmalloc/mmalloc.texi.
3576 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3577 'help info proc' for details.
3579 * MIPS ecoff symbol table format
3581 The code that reads MIPS symbol table format is now supported on all hosts.
3582 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3585 * File name changes for MS-DOS
3587 Many files in the config directories have been renamed to make it easier to
3588 support GDB on MS-DOSe systems (which have very restrictive file name
3589 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3590 environment) is close to working but has some remaining problems. Note
3591 that debugging of DOS programs is not supported, due to limitations
3592 in the ``operating system'', but it can be used to host cross-debugging.
3594 * Cross byte order fixes
3596 Many fixes have been made to support cross debugging of Sparc and MIPS
3597 targets from hosts whose byte order differs.
3599 * New -mapped and -readnow options
3601 If memory-mapped files are available on your system through the 'mmap'
3602 system call, you can use the -mapped option on the `file' or
3603 `symbol-file' commands to cause GDB to write the symbols from your
3604 program into a reusable file. If the program you are debugging is
3605 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3606 Future GDB debugging sessions will notice the presence of this file,
3607 and will quickly map in symbol information from it, rather than reading
3608 the symbol table from the executable program. Using the '-mapped'
3609 option in a GDB `file' or `symbol-file' command has the same effect as
3610 starting GDB with the '-mapped' command-line option.
3612 You can cause GDB to read the entire symbol table immediately by using
3613 the '-readnow' option with any of the commands that load symbol table
3614 information (or on the GDB command line). This makes the command
3615 slower, but makes future operations faster.
3617 The -mapped and -readnow options are typically combined in order to
3618 build a `fred.syms' file that contains complete symbol information.
3619 A simple GDB invocation to do nothing but build a `.syms' file for future
3622 gdb -batch -nx -mapped -readnow programname
3624 The `.syms' file is specific to the host machine on which GDB is run.
3625 It holds an exact image of GDB's internal symbol table. It cannot be
3626 shared across multiple host platforms.
3628 * longjmp() handling
3630 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3631 siglongjmp() without losing control. This feature has not yet been ported to
3632 all systems. It currently works on many 386 platforms, all MIPS-based
3633 platforms (SGI, DECstation, etc), and Sun3/4.
3637 Preliminary work has been put in to support the new Solaris OS from Sun. At
3638 this time, it can control and debug processes, but it is not capable of
3643 As always, many many bug fixes. The major areas were with g++, and mipsread.
3644 People using the MIPS-based platforms should experience fewer mysterious
3645 crashes and trashed symbol tables.
3647 *** Changes in GDB-4.4:
3649 * New machines supported (host and target)
3651 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3653 BSD Reno on Vax vax-dec-bsd
3654 Ultrix on Vax vax-dec-ultrix
3656 * New machines supported (target)
3658 AMD 29000 embedded, using EBMON a29k-none-none
3662 GDB continues to improve its handling of C++. `References' work better.
3663 The demangler has also been improved, and now deals with symbols mangled as
3664 per the Annotated C++ Reference Guide.
3666 GDB also now handles `stabs' symbol information embedded in MIPS
3667 `ecoff' symbol tables. Since the ecoff format was not easily
3668 extensible to handle new languages such as C++, this appeared to be a
3669 good way to put C++ debugging info into MIPS binaries. This option
3670 will be supported in the GNU C compiler, version 2, when it is
3673 * New features for SVR4
3675 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3676 shared libraries. Debugging dynamically linked programs should present
3677 only minor differences from debugging statically linked programs.
3679 The `info proc' command will print out information about any process
3680 on an SVR4 system (including the one you are debugging). At the moment,
3681 it prints the address mappings of the process.
3683 If you bring up GDB on another SVR4 system, please send mail to
3684 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3686 * Better dynamic linking support in SunOS
3688 Reading symbols from shared libraries which contain debugging symbols
3689 now works properly. However, there remain issues such as automatic
3690 skipping of `transfer vector' code during function calls, which
3691 make it harder to debug code in a shared library, than to debug the
3692 same code linked statically.
3696 GDB is now using the latest `getopt' routines from the FSF. This
3697 version accepts the -- prefix for options with long names. GDB will
3698 continue to accept the old forms (-option and +option) as well.
3699 Various single letter abbreviations for options have been explicity
3700 added to the option table so that they won't get overshadowed in the
3701 future by other options that begin with the same letter.
3705 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3706 Many assorted bugs have been handled. Many more remain to be handled.
3707 See the various ChangeLog files (primarily in gdb and bfd) for details.
3710 *** Changes in GDB-4.3:
3712 * New machines supported (host and target)
3714 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3715 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3716 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3718 * Almost SCO Unix support
3720 We had hoped to support:
3721 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3722 (except for core file support), but we discovered very late in the release
3723 that it has problems with process groups that render gdb unusable. Sorry
3724 about that. I encourage people to fix it and post the fixes.
3726 * Preliminary ELF and DWARF support
3728 GDB can read ELF object files on System V Release 4, and can handle
3729 debugging records for C, in DWARF format, in ELF files. This support
3730 is preliminary. If you bring up GDB on another SVR4 system, please
3731 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3736 GDB now uses the latest `readline' library. One user-visible change
3737 is that two tabs will list possible command completions, which previously
3738 required typing M-? (meta-question mark, or ESC ?).
3742 The `stepi' bug that many of you noticed has been squashed.
3743 Many bugs in C++ have been handled. Many more remain to be handled.
3744 See the various ChangeLog files (primarily in gdb and bfd) for details.
3746 * State of the MIPS world (in case you wondered):
3748 GDB can understand the symbol tables emitted by the compilers
3749 supplied by most vendors of MIPS-based machines, including DEC. These
3750 symbol tables are in a format that essentially nobody else uses.
3752 Some versions of gcc come with an assembler post-processor called
3753 mips-tfile. This program is required if you want to do source-level
3754 debugging of gcc-compiled programs. I believe FSF does not ship
3755 mips-tfile with gcc version 1, but it will eventually come with gcc
3758 Debugging of g++ output remains a problem. g++ version 1.xx does not
3759 really support it at all. (If you're lucky, you should be able to get
3760 line numbers and stack traces to work, but no parameters or local
3761 variables.) With some work it should be possible to improve the
3764 When gcc version 2 is released, you will have somewhat better luck.
3765 However, even then you will get confusing results for inheritance and
3768 We will eventually provide full debugging of g++ output on
3769 DECstations. This will probably involve some kind of stabs-in-ecoff
3770 encapulation, but the details have not been worked out yet.
3773 *** Changes in GDB-4.2:
3775 * Improved configuration
3777 Only one copy of `configure' exists now, and it is not self-modifying.
3778 Porting BFD is simpler.
3782 The `step' and `next' commands now only stop at the first instruction
3783 of a source line. This prevents the multiple stops that used to occur
3784 in switch statements, for-loops, etc. `Step' continues to stop if a
3785 function that has debugging information is called within the line.
3789 Lots of small bugs fixed. More remain.
3791 * New host supported (not target)
3793 Intel 386 PC clone running Mach i386-none-mach
3796 *** Changes in GDB-4.1:
3798 * Multiple source language support
3800 GDB now has internal scaffolding to handle several source languages.
3801 It determines the type of each source file from its filename extension,
3802 and will switch expression parsing and number formatting to match the
3803 language of the function in the currently selected stack frame.
3804 You can also specifically set the language to be used, with
3805 `set language c' or `set language modula-2'.
3809 GDB now has preliminary support for the GNU Modula-2 compiler,
3810 currently under development at the State University of New York at
3811 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3812 continue through the fall of 1991 and into 1992.
3814 Other Modula-2 compilers are currently not supported, and attempting to
3815 debug programs compiled with them will likely result in an error as the
3816 symbol table is read. Feel free to work on it, though!
3818 There are hooks in GDB for strict type checking and range checking,
3819 in the `Modula-2 philosophy', but they do not currently work.
3823 GDB can now write to executable and core files (e.g. patch
3824 a variable's value). You must turn this switch on, specify
3825 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3826 by assigning a new value to a variable. Modifications take
3829 * Automatic SunOS shared library reading
3831 When you run your program, GDB automatically determines where its
3832 shared libraries (if any) have been loaded, and reads their symbols.
3833 The `share' command is no longer needed. This also works when
3834 examining core files.
3838 You can specify the number of lines that the `list' command shows.
3841 * New machines supported (host and target)
3843 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3844 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3845 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3847 * New hosts supported (not targets)
3849 IBM RT/PC: romp-ibm-aix or rtpc
3851 * New targets supported (not hosts)
3853 AMD 29000 embedded with COFF a29k-none-coff
3854 AMD 29000 embedded with a.out a29k-none-aout
3855 Ultracomputer remote kernel debug a29k-nyu-kern
3857 * New remote interfaces
3863 *** Changes in GDB-4.0:
3867 Wide output is wrapped at good places to make the output more readable.
3869 Gdb now supports cross-debugging from a host machine of one type to a
3870 target machine of another type. Communication with the target system
3871 is over serial lines. The ``target'' command handles connecting to the
3872 remote system; the ``load'' command will download a program into the
3873 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3874 also supports debugging of realtime processes running under VxWorks,
3875 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3876 stub on the target system.
3878 New CPUs supported include the AMD 29000 and Intel 960.
3880 GDB now reads object files and symbol tables via a ``binary file''
3881 library, which allows a single copy of GDB to debug programs of multiple
3882 object file types such as a.out and coff.
3884 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3885 refcard.dvi and refcard.ps are available to format it).
3888 * Control-Variable user interface simplified
3890 All variables that control the operation of the debugger can be set
3891 by the ``set'' command, and displayed by the ``show'' command.
3893 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3894 ``Show prompt'' produces the response:
3895 Gdb's prompt is new-gdb=>.
3897 What follows are the NEW set commands. The command ``help set'' will
3898 print a complete list of old and new set commands. ``help set FOO''
3899 will give a longer description of the variable FOO. ``show'' will show
3900 all of the variable descriptions and their current settings.
3902 confirm on/off: Enables warning questions for operations that are
3903 hard to recover from, e.g. rerunning the program while
3904 it is already running. Default is ON.
3906 editing on/off: Enables EMACS style command line editing
3907 of input. Previous lines can be recalled with
3908 control-P, the current line can be edited with control-B,
3909 you can search for commands with control-R, etc.
3912 history filename NAME: NAME is where the gdb command history
3913 will be stored. The default is .gdb_history,
3914 or the value of the environment variable
3917 history size N: The size, in commands, of the command history. The
3918 default is 256, or the value of the environment variable
3921 history save on/off: If this value is set to ON, the history file will
3922 be saved after exiting gdb. If set to OFF, the
3923 file will not be saved. The default is OFF.
3925 history expansion on/off: If this value is set to ON, then csh-like
3926 history expansion will be performed on
3927 command line input. The default is OFF.
3929 radix N: Sets the default radix for input and output. It can be set
3930 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3931 in the current radix, so "set radix 10" is always a no-op.
3933 height N: This integer value is the number of lines on a page. Default
3934 is 24, the current `stty rows'' setting, or the ``li#''
3935 setting from the termcap entry matching the environment
3938 width N: This integer value is the number of characters on a line.
3939 Default is 80, the current `stty cols'' setting, or the ``co#''
3940 setting from the termcap entry matching the environment
3943 Note: ``set screensize'' is obsolete. Use ``set height'' and
3944 ``set width'' instead.
3946 print address on/off: Print memory addresses in various command displays,
3947 such as stack traces and structure values. Gdb looks
3948 more ``symbolic'' if you turn this off; it looks more
3949 ``machine level'' with it on. Default is ON.
3951 print array on/off: Prettyprint arrays. New convenient format! Default
3954 print demangle on/off: Print C++ symbols in "source" form if on,
3957 print asm-demangle on/off: Same, for assembler level printouts
3960 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3963 * Support for Epoch Environment.
3965 The epoch environment is a version of Emacs v18 with windowing. One
3966 new command, ``inspect'', is identical to ``print'', except that if you
3967 are running in the epoch environment, the value is printed in its own
3971 * Support for Shared Libraries
3973 GDB can now debug programs and core files that use SunOS shared libraries.
3974 Symbols from a shared library cannot be referenced
3975 before the shared library has been linked with the program (this
3976 happens after you type ``run'' and before the function main() is entered).
3977 At any time after this linking (including when examining core files
3978 from dynamically linked programs), gdb reads the symbols from each
3979 shared library when you type the ``sharedlibrary'' command.
3980 It can be abbreviated ``share''.
3982 sharedlibrary REGEXP: Load shared object library symbols for files
3983 matching a unix regular expression. No argument
3984 indicates to load symbols for all shared libraries.
3986 info sharedlibrary: Status of loaded shared libraries.
3991 A watchpoint stops execution of a program whenever the value of an
3992 expression changes. Checking for this slows down execution
3993 tremendously whenever you are in the scope of the expression, but is
3994 quite useful for catching tough ``bit-spreader'' or pointer misuse
3995 problems. Some machines such as the 386 have hardware for doing this
3996 more quickly, and future versions of gdb will use this hardware.
3998 watch EXP: Set a watchpoint (breakpoint) for an expression.
4000 info watchpoints: Information about your watchpoints.
4002 delete N: Deletes watchpoint number N (same as breakpoints).
4003 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4004 enable N: Re-enables watchpoint number N (same as breakpoints).
4007 * C++ multiple inheritance
4009 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4012 * C++ exception handling
4014 Gdb now supports limited C++ exception handling. Besides the existing
4015 ability to breakpoint on an exception handler, gdb can breakpoint on
4016 the raising of an exception (before the stack is peeled back to the
4019 catch FOO: If there is a FOO exception handler in the dynamic scope,
4020 set a breakpoint to catch exceptions which may be raised there.
4021 Multiple exceptions (``catch foo bar baz'') may be caught.
4023 info catch: Lists all exceptions which may be caught in the
4024 current stack frame.
4027 * Minor command changes
4029 The command ``call func (arg, arg, ...)'' now acts like the print
4030 command, except it does not print or save a value if the function's result
4031 is void. This is similar to dbx usage.
4033 The ``up'' and ``down'' commands now always print the frame they end up
4034 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4035 frames without printing.
4037 * New directory command
4039 'dir' now adds directories to the FRONT of the source search path.
4040 The path starts off empty. Source files that contain debug information
4041 about the directory in which they were compiled can be found even
4042 with an empty path; Sun CC and GCC include this information. If GDB can't
4043 find your source file in the current directory, type "dir .".
4045 * Configuring GDB for compilation
4047 For normal use, type ``./configure host''. See README or gdb.texinfo
4050 GDB now handles cross debugging. If you are remotely debugging between
4051 two different machines, type ``./configure host -target=targ''.
4052 Host is the machine where GDB will run; targ is the machine
4053 where the program that you are debugging will run.