1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.1
6 * X86 general purpose registers
8 GDB now supports reading/writing byte, word and double-word x86
9 general purpose registers directly. This means you can use, say,
10 $ah or $ax to refer, respectively, to the byte register AH and
11 16-bit word register AX that are actually portions of the 32-bit
12 register EAX or 64-bit register RAX.
16 The GDB Python API now has access to symbols, symbol tables, and
21 ARM Symbian arm*-*-symbianelf*
23 *** Changes in GDB 7.1
29 GDB now supports importing of namespaces in C++. This enables the
30 user to inspect variables from imported namespaces. Support for
31 namepace aliasing has also been added. So, if a namespace is
32 aliased in the current scope (e.g. namepace C=A; ) the user can
33 print variables using the alias (e.g. (gdb) print C::x).
37 All known bugs relating to the printing of virtual base class were
38 fixed. It is now possible to call overloaded static methods using a
43 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
44 and reinterpret_cast<> are now handled by the C++ expression parser.
48 Xilinx MicroBlaze microblaze-*-*
53 Xilinx MicroBlaze microblaze
56 * Multi-program debugging.
58 GDB now has support for multi-program (a.k.a. multi-executable or
59 multi-exec) debugging. This allows for debugging multiple inferiors
60 simultaneously each running a different program under the same GDB
61 session. See "Debugging Multiple Inferiors and Programs" in the
62 manual for more information. This implied some user visible changes
63 in the multi-inferior support. For example, "info inferiors" now
64 lists inferiors that are not running yet or that have exited
65 already. See also "New commands" and "New options" below.
67 * New tracing features
69 GDB's tracepoint facility now includes several new features:
71 ** Trace state variables
73 GDB tracepoints now include support for trace state variables, which
74 are variables managed by the target agent during a tracing
75 experiment. They are useful for tracepoints that trigger each
76 other, so for instance one tracepoint can count hits in a variable,
77 and then a second tracepoint has a condition that is true when the
78 count reaches a particular value. Trace state variables share the
79 $-syntax of GDB convenience variables, and can appear in both
80 tracepoint actions and condition expressions. Use the "tvariable"
81 command to create, and "info tvariables" to view; see "Trace State
82 Variables" in the manual for more detail.
86 GDB now includes an option for defining fast tracepoints, which
87 targets may implement more efficiently, such as by installing a jump
88 into the target agent rather than a trap instruction. The resulting
89 speedup can be by two orders of magnitude or more, although the
90 tradeoff is that some program locations on some target architectures
91 might not allow fast tracepoint installation, for instance if the
92 instruction to be replaced is shorter than the jump. To request a
93 fast tracepoint, use the "ftrace" command, with syntax identical to
94 the regular trace command.
96 ** Disconnected tracing
98 It is now possible to detach GDB from the target while it is running
99 a trace experiment, then reconnect later to see how the experiment
100 is going. In addition, a new variable disconnected-tracing lets you
101 tell the target agent whether to continue running a trace if the
102 connection is lost unexpectedly.
106 GDB now has the ability to save the trace buffer into a file, and
107 then use that file as a target, similarly to you can do with
108 corefiles. You can select trace frames, print data that was
109 collected in them, and use tstatus to display the state of the
110 tracing run at the moment that it was saved. To create a trace
111 file, use "tsave <filename>", and to use it, do "target tfile
117 The disassemble command, when invoked with two arguments, now requires
118 the arguments to be comma-separated.
121 The info variables command now displays variable definitions. Files
122 which only declare a variable are not shown.
125 The source command is now capable of sourcing Python scripts.
126 This feature is dependent on the debugger being build with Python
129 Related to this enhancement is also the introduction of a new command
130 "set script-extension" (see below).
132 * New commands (for set/show, see "New options" below)
134 record save [<FILENAME>]
135 Save a file (in core file format) containing the process record
136 execution log for replay debugging at a later time.
138 record restore <FILENAME>
139 Restore the process record execution log that was saved at an
140 earlier time, for replay debugging.
142 add-inferior [-copies <N>] [-exec <FILENAME>]
145 clone-inferior [-copies <N>] [ID]
146 Make a new inferior ready to execute the same program another
152 maint info program-spaces
153 List the program spaces loaded into GDB.
155 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
156 show remote interrupt-sequence
157 Allow the user to select one of ^C, a BREAK signal or BREAK-g
158 as the sequence to the remote target in order to interrupt the execution.
159 Ctrl-C is a default. Some system prefers BREAK which is high level of
160 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
161 Magic SysRq g. It is BREAK signal and character 'g'.
163 set remote interrupt-on-connect [on | off]
164 show remote interrupt-on-connect
165 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
166 remote target when gdb connects to it. This is needed when you debug
169 set remotebreak [on | off]
171 Deprecated. Use "set/show remote interrupt-sequence" instead.
173 tvariable $NAME [ = EXP ]
174 Create or modify a trace state variable.
177 List trace state variables and their values.
179 delete tvariable $NAME ...
180 Delete one or more trace state variables.
183 Evaluate the given expressions without collecting anything into the
184 trace buffer. (Valid in tracepoint actions only.)
186 ftrace FN / FILE:LINE / *ADDR
187 Define a fast tracepoint at the given function, line, or address.
189 * New expression syntax
191 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
192 GDB now parses 0b101010 identically with 42.
196 set follow-exec-mode new|same
197 show follow-exec-mode
198 Control whether GDB reuses the same inferior across an exec call or
199 creates a new one. This is useful to be able to restart the old
200 executable after the inferior having done an exec call.
202 set default-collect EXPR, ...
204 Define a list of expressions to be collected at each tracepoint.
205 This is a useful way to ensure essential items are not overlooked,
206 such as registers or a critical global variable.
208 set disconnected-tracing
209 show disconnected-tracing
210 If set to 1, the target is instructed to continue tracing if it
211 loses its connection to GDB. If 0, the target is to stop tracing
214 set script-extension off|soft|strict
215 show script-extension
216 If set to "off", the debugger does not perform any script language
217 recognition, and all sourced files are assumed to be GDB scripts.
218 If set to "soft" (the default), files are sourced according to
219 filename extension, falling back to GDB scripts if the first
221 If set to "strict", files are sourced according to filename extension.
223 set ada trust-PAD-over-XVS on|off
224 show ada trust-PAD-over-XVS
225 If off, activate a workaround against a bug in the debugging information
226 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
227 the GCC sources for more information about the GNAT encoding and
228 PAD types in particular). It is always safe to set this option to
229 off, but this introduces a slight performance penalty. The default
232 * Python API Improvements
234 ** GDB provides the new class gdb.LazyString. This is useful in
235 some pretty-printing cases. The new method gdb.Value.lazy_string
236 provides a simple way to create objects of this type.
238 ** The fields returned by gdb.Type.fields now have an
239 `is_base_class' attribute.
241 ** The new method gdb.Type.range returns the range of an array type.
243 ** The new method gdb.parse_and_eval can be used to parse and
244 evaluate an expression.
249 Define a trace state variable.
252 Get the current value of a trace state variable.
255 Set desired tracing behavior upon disconnection.
258 Get data about the tracepoints currently in use.
262 Process record now works correctly with hardware watchpoints.
264 Multiple bug fixes have been made to the mips-irix port, making it
265 much more reliable. In particular:
266 - Debugging threaded applications is now possible again. Previously,
267 GDB would hang while starting the program, or while waiting for
268 the program to stop at a breakpoint.
269 - Attaching to a running process no longer hangs.
270 - An error occurring while loading a core file has been fixed.
271 - Changing the value of the PC register now works again. This fixes
272 problems observed when using the "jump" command, or when calling
273 a function from GDB, or even when assigning a new value to $pc.
274 - With the "finish" and "return" commands, the return value for functions
275 returning a small array is now correctly printed.
276 - It is now possible to break on shared library code which gets executed
277 during a shared library init phase (code executed while executing
278 their .init section). Previously, the breakpoint would have no effect.
279 - GDB is now able to backtrace through the signal handler for
280 non-threaded programs.
282 PIE (Position Independent Executable) programs debugging is now supported.
283 This includes debugging execution of PIC (Position Independent Code) shared
284 libraries although for that, it should be possible to run such libraries as an
287 *** Changes in GDB 7.0
289 * GDB now has an interface for JIT compilation. Applications that
290 dynamically generate code can create symbol files in memory and register
291 them with GDB. For users, the feature should work transparently, and
292 for JIT developers, the interface is documented in the GDB manual in the
293 "JIT Compilation Interface" chapter.
295 * Tracepoints may now be conditional. The syntax is as for
296 breakpoints; either an "if" clause appended to the "trace" command,
297 or the "condition" command is available. GDB sends the condition to
298 the target for evaluation using the same bytecode format as is used
299 for tracepoint actions.
301 * "disassemble" command with a /r modifier, print the raw instructions
302 in hex as well as in symbolic form.
304 * Process record and replay
306 In a architecture environment that supports ``process record and
307 replay'', ``process record and replay'' target can record a log of
308 the process execution, and replay it with both forward and reverse
311 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
312 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
313 set execution-direction {forward|reverse}, for targets that support
316 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
317 feature is available with a native GDB running on kernel version
320 * GDB now has support for multi-byte and wide character sets on the
321 target. Strings whose character type is wchar_t, char16_t, or
322 char32_t are now correctly printed. GDB supports wide- and unicode-
323 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
324 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
325 `printf'. This feature requires iconv to work properly; if your
326 system does not have a working iconv, GDB can use GNU libiconv. See
327 the installation instructions for more information.
329 * GDB now supports automatic retrieval of shared library files from
330 remote targets. To use this feature, specify a system root that begins
331 with the `remote:' prefix, either via the `set sysroot' command or via
332 the `--with-sysroot' configure-time option.
334 * "info sharedlibrary" now takes an optional regex of libraries to show,
335 and it now reports if a shared library has no debugging information.
337 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
338 now complete on file names.
340 * When completing in expressions, gdb will attempt to limit
341 completions to allowable structure or union fields, where appropriate.
342 For instance, consider:
344 # struct example { int f1; double f2; };
345 # struct example variable;
348 If the user types TAB at the end of this command line, the available
349 completions will be "f1" and "f2".
351 * Inlined functions are now supported. They show up in backtraces, and
352 the "step", "next", and "finish" commands handle them automatically.
354 * GDB now supports the token-splicing (##) and stringification (#)
355 operators when expanding macros. It also supports variable-arity
358 * GDB now supports inspecting extra signal information, exported by
359 the new $_siginfo convenience variable. The feature is currently
360 implemented on linux ARM, i386 and amd64.
362 * GDB can now display the VFP floating point registers and NEON vector
363 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
364 can provide these registers (requires Linux 2.6.30 or later). Remote
365 and simulator targets may also provide them.
370 Search memory for a sequence of bytes.
373 Turn off `+'/`-' protocol acknowledgments to permit more efficient
374 operation over reliable transport links. Use of this packet is
375 controlled by the `set remote noack-packet' command.
378 Kill the process with the specified process ID. Use this in preference
379 to `k' when multiprocess protocol extensions are supported.
382 Obtains additional operating system information
386 Read or write additional signal information.
388 * Removed remote protocol undocumented extension
390 An undocumented extension to the remote protocol's `S' stop reply
391 packet that permited the stub to pass a process id was removed.
392 Remote servers should use the `T' stop reply packet instead.
394 * The "disassemble" command now supports an optional /m modifier to print mixed
397 * GDB now supports multiple function calling conventions according to the
398 DWARF-2 DW_AT_calling_convention function attribute.
400 * The SH target utilizes the aforementioned change to distinguish between gcc
401 and Renesas calling convention. It also adds the new CLI commands
402 `set/show sh calling-convention'.
404 * GDB can now read compressed debug sections, as produced by GNU gold
405 with the --compress-debug-sections=zlib flag.
407 * 64-bit core files are now supported on AIX.
409 * Thread switching is now supported on Tru64.
411 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
412 which will be allocated using malloc later in program execution.
414 * The qXfer:libraries:read remote procotol packet now allows passing a
415 list of section offsets.
417 * On GNU/Linux, GDB can now attach to stopped processes. Several race
418 conditions handling signals delivered during attach or thread creation
419 have also been fixed.
421 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
422 From the user's standpoint, all unqualified instances of True and False
423 are treated as the standard definitions, regardless of context.
425 * GDB now parses C++ symbol and type names more flexibly. For
428 template<typename T> class C { };
431 GDB will now correctly handle all of:
433 ptype C<char const *>
435 ptype C<const char *>
438 * New features in the GDB remote stub, gdbserver
440 - The "--wrapper" command-line argument tells gdbserver to use a
441 wrapper program to launch programs for debugging.
443 - On PowerPC and S/390 targets, it is now possible to use a single
444 gdbserver executable to debug both 32-bit and 64-bit programs.
445 (This requires gdbserver itself to be built as a 64-bit executable.)
447 - gdbserver uses the new noack protocol mode for TCP connections to
448 reduce communications latency, if also supported and enabled in GDB.
450 - Support for the sparc64-linux-gnu target is now included in
453 - The amd64-linux build of gdbserver now supports debugging both
454 32-bit and 64-bit programs.
456 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
457 now support hardware watchpoints, and will use them automatically
462 GDB now has support for scripting using Python. Whether this is
463 available is determined at configure time.
465 New GDB commands can now be written in Python.
467 * Ada tasking support
469 Ada tasks can now be inspected in GDB. The following commands have
473 Print the list of Ada tasks.
475 Print detailed information about task number N.
477 Print the task number of the current task.
479 Switch the context of debugging to task number N.
481 * Support for user-defined prefixed commands. The "define" command can
482 add new commands to existing prefixes, e.g. "target".
484 * Multi-inferior, multi-process debugging.
486 GDB now has generalized support for multi-inferior debugging. See
487 "Debugging Multiple Inferiors" in the manual for more information.
488 Although availability still depends on target support, the command
489 set is more uniform now. The GNU/Linux specific multi-forks support
490 has been migrated to this new framework. This implied some user
491 visible changes; see "New commands" and also "Removed commands"
494 * Target descriptions can now describe the target OS ABI. See the
495 "Target Description Format" section in the user manual for more
498 * Target descriptions can now describe "compatible" architectures
499 to indicate that the target can execute applications for a different
500 architecture in addition to those for the main target architecture.
501 See the "Target Description Format" section in the user manual for
504 * Multi-architecture debugging.
506 GDB now includes general supports for debugging applications on
507 hybrid systems that use more than one single processor architecture
508 at the same time. Each such hybrid architecture still requires
509 specific support to be added. The only hybrid architecture supported
510 in this version of GDB is the Cell Broadband Engine.
512 * GDB now supports integrated debugging of Cell/B.E. applications that
513 use both the PPU and SPU architectures. To enable support for hybrid
514 Cell/B.E. debugging, you need to configure GDB to support both the
515 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
516 --enable-targets configure option.
518 * Non-stop mode debugging.
520 For some targets, GDB now supports an optional mode of operation in
521 which you can examine stopped threads while other threads continue
522 to execute freely. This is referred to as non-stop mode, with the
523 old mode referred to as all-stop mode. See the "Non-Stop Mode"
524 section in the user manual for more information.
526 To be able to support remote non-stop debugging, a remote stub needs
527 to implement the non-stop mode remote protocol extensions, as
528 described in the "Remote Non-Stop" section of the user manual. The
529 GDB remote stub, gdbserver, has been adjusted to support these
530 extensions on linux targets.
532 * New commands (for set/show, see "New options" below)
534 catch syscall [NAME(S) | NUMBER(S)]
535 Catch system calls. Arguments, which should be names of system
536 calls or their numbers, mean catch only those syscalls. Without
537 arguments, every syscall will be caught. When the inferior issues
538 any of the specified syscalls, GDB will stop and announce the system
539 call, both when it is called and when its call returns. This
540 feature is currently available with a native GDB running on the
541 Linux Kernel, under the following architectures: x86, x86_64,
542 PowerPC and PowerPC64.
544 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
546 Search memory for a sequence of bytes.
548 maint set python print-stack
549 maint show python print-stack
550 Show a stack trace when an error is encountered in a Python script.
553 Invoke CODE by passing it to the Python interpreter.
558 These allow macros to be defined, undefined, and listed
562 Show operating system information about processes.
565 List the inferiors currently under GDB's control.
568 Switch focus to inferior number NUM.
571 Detach from inferior number NUM.
574 Kill inferior number NUM.
579 show spu stop-on-load
580 Control whether to stop for new SPE threads during Cell/B.E. debugging.
582 set spu auto-flush-cache
583 show spu auto-flush-cache
584 Control whether to automatically flush the software-managed cache
585 during Cell/B.E. debugging.
587 set sh calling-convention
588 show sh calling-convention
589 Control the calling convention used when calling SH target functions.
593 Control display of timestamps with GDB debugging output.
595 set disassemble-next-line
596 show disassemble-next-line
597 Control display of disassembled source lines or instructions when
600 set remote noack-packet
601 show remote noack-packet
602 Set/show the use of remote protocol QStartNoAckMode packet. See above
603 under "New remote packets."
605 set remote query-attached-packet
606 show remote query-attached-packet
607 Control use of remote protocol `qAttached' (query-attached) packet.
609 set remote read-siginfo-object
610 show remote read-siginfo-object
611 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
614 set remote write-siginfo-object
615 show remote write-siginfo-object
616 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
619 set remote reverse-continue
620 show remote reverse-continue
621 Control use of remote protocol 'bc' (reverse-continue) packet.
623 set remote reverse-step
624 show remote reverse-step
625 Control use of remote protocol 'bs' (reverse-step) packet.
627 set displaced-stepping
628 show displaced-stepping
629 Control displaced stepping mode. Displaced stepping is a way to
630 single-step over breakpoints without removing them from the debuggee.
631 Also known as "out-of-line single-stepping".
635 Control display of debugging info for displaced stepping.
637 maint set internal-error
638 maint show internal-error
639 Control what GDB does when an internal error is detected.
641 maint set internal-warning
642 maint show internal-warning
643 Control what GDB does when an internal warning is detected.
648 Use a wrapper program to launch programs for debugging.
650 set multiple-symbols (all|ask|cancel)
651 show multiple-symbols
652 The value of this variable can be changed to adjust the debugger behavior
653 when an expression or a breakpoint location contains an ambiguous symbol
654 name (an overloaded function name, for instance).
656 set breakpoint always-inserted
657 show breakpoint always-inserted
658 Keep breakpoints always inserted in the target, as opposed to inserting
659 them when resuming the target, and removing them when the target stops.
660 This option can improve debugger performance on slow remote targets.
662 set arm fallback-mode (arm|thumb|auto)
663 show arm fallback-mode
664 set arm force-mode (arm|thumb|auto)
666 These commands control how ARM GDB determines whether instructions
667 are ARM or Thumb. The default for both settings is auto, which uses
668 the current CPSR value for instructions without symbols; previous
669 versions of GDB behaved as if "set arm fallback-mode arm".
671 set disable-randomization
672 show disable-randomization
673 Standalone programs run with the virtual address space randomization enabled
674 by default on some platforms. This option keeps the addresses stable across
675 multiple debugging sessions.
679 Control whether other threads are stopped or not when some thread hits
684 Requests that asynchronous execution is enabled in the target, if available.
685 In this case, it's possible to resume target in the background, and interact
686 with GDB while the target is running. "show target-async" displays the
687 current state of asynchronous execution of the target.
689 set target-wide-charset
690 show target-wide-charset
691 The target-wide-charset is the name of the character set that GDB
692 uses when printing characters whose type is wchar_t.
694 set tcp auto-retry (on|off)
696 set tcp connect-timeout
697 show tcp connect-timeout
698 These commands allow GDB to retry failed TCP connections to a remote stub
699 with a specified timeout period; this is useful if the stub is launched
700 in parallel with GDB but may not be ready to accept connections immediately.
702 set libthread-db-search-path
703 show libthread-db-search-path
704 Control list of directories which GDB will search for appropriate
707 set schedule-multiple (on|off)
708 show schedule-multiple
709 Allow GDB to resume all threads of all processes or only threads of
714 Use more aggressive caching for accesses to the stack. This improves
715 performance of remote debugging (particularly backtraces) without
716 affecting correctness.
718 set interactive-mode (on|off|auto)
719 show interactive-mode
720 Control whether GDB runs in interactive mode (on) or not (off).
721 When in interactive mode, GDB waits for the user to answer all
722 queries. Otherwise, GDB does not wait and assumes the default
723 answer. When set to auto (the default), GDB determines which
724 mode to use based on the stdin settings.
729 For program forks, this is replaced by the new more generic `info
730 inferiors' command. To list checkpoints, you can still use the
731 `info checkpoints' command, which was an alias for the `info forks'
735 Replaced by the new `inferior' command. To switch between
736 checkpoints, you can still use the `restart' command, which was an
737 alias for the `fork' command.
740 This is removed, since some targets don't have a notion of
741 processes. To switch between processes, you can still use the
742 `inferior' command using GDB's own inferior number.
745 For program forks, this is replaced by the new more generic `kill
746 inferior' command. To delete a checkpoint, you can still use the
747 `delete checkpoint' command, which was an alias for the `delete
751 For program forks, this is replaced by the new more generic `detach
752 inferior' command. To detach a checkpoint, you can still use the
753 `detach checkpoint' command, which was an alias for the `detach
756 * New native configurations
758 x86/x86_64 Darwin i[34567]86-*-darwin*
760 x86_64 MinGW x86_64-*-mingw*
764 Lattice Mico32 lm32-*
765 x86 DICOS i[34567]86-*-dicos*
766 x86_64 DICOS x86_64-*-dicos*
769 * The GDB remote stub, gdbserver, now supports x86 Windows CE
770 (mingw32ce) debugging.
776 These commands were actually not implemented on any target.
778 *** Changes in GDB 6.8
780 * New native configurations
782 NetBSD/hppa hppa*-*netbsd*
783 Xtensa GNU/Linux xtensa*-*-linux*
787 NetBSD/hppa hppa*-*-netbsd*
788 Xtensa GNU/Lunux xtensa*-*-linux*
790 * Change in command line behavior -- corefiles vs. process ids.
792 When the '-p NUMBER' or '--pid NUMBER' options are used, and
793 attaching to process NUMBER fails, GDB no longer attempts to open a
794 core file named NUMBER. Attaching to a program using the -c option
795 is no longer supported. Instead, use the '-p' or '--pid' options.
797 * GDB can now be built as a native debugger for debugging Windows x86
798 (mingw32) Portable Executable (PE) programs.
800 * Pending breakpoints no longer change their number when their address
803 * GDB now supports breakpoints with multiple locations,
804 including breakpoints on C++ constructors, inside C++ templates,
805 and in inlined functions.
807 * GDB's ability to debug optimized code has been improved. GDB more
808 accurately identifies function bodies and lexical blocks that occupy
809 more than one contiguous range of addresses.
811 * Target descriptions can now describe registers for PowerPC.
813 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
814 registers on PowerPC targets.
816 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
817 targets even when the libthread_db library is not available.
819 * The GDB remote stub, gdbserver, now supports the new file transfer
820 commands (remote put, remote get, and remote delete).
822 * The GDB remote stub, gdbserver, now supports run and attach in
823 extended-remote mode.
825 * hppa*64*-*-hpux11* target broken
826 The debugger is unable to start a program and fails with the following
827 error: "Error trying to get information about dynamic linker".
828 The gdb-6.7 release is also affected.
830 * GDB now supports the --enable-targets= configure option to allow
831 building a single GDB executable that supports multiple remote
832 target architectures.
834 * GDB now supports debugging C and C++ programs which use the
835 Decimal Floating Point extension. In addition, the PowerPC target
836 now has a set of pseudo-registers to inspect decimal float values
837 stored in two consecutive float registers.
839 * The -break-insert MI command can optionally create pending
842 * Improved support for debugging Ada
843 Many improvements to the Ada language support have been made. These
845 - Better support for Ada2005 interface types
846 - Improved handling of arrays and slices in general
847 - Better support for Taft-amendment types
848 - The '{type} ADDRESS' expression is now allowed on the left hand-side
850 - Improved command completion in Ada
853 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
858 set print frame-arguments (all|scalars|none)
859 show print frame-arguments
860 The value of this variable can be changed to control which argument
861 values should be printed by the debugger when displaying a frame.
866 Transfer files to and from a remote target, and delete remote files.
873 Transfer files to and from a remote target, and delete remote files.
882 Open, close, read, write, and delete files on the remote system.
885 Attach to an existing process on the remote system, in extended-remote
889 Run a new process on the remote system, in extended-remote mode.
891 *** Changes in GDB 6.7
893 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
894 bfd, libiberty and opcodes, as revealed by static analysis donated by
895 Coverity, Inc. (http://scan.coverity.com).
897 * When looking up multiply-defined global symbols, GDB will now prefer the
898 symbol definition in the current shared library if it was built using the
899 -Bsymbolic linker option.
901 * When the Text User Interface (TUI) is not configured, GDB will now
902 recognize the -tui command-line option and print a message that the TUI
905 * The GDB remote stub, gdbserver, now has lower overhead for high
906 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
908 * GDB for MIPS targets now autodetects whether a remote target provides
909 32-bit or 64-bit register values.
911 * Support for C++ member pointers has been improved.
913 * GDB now understands XML target descriptions, which specify the
914 target's overall architecture. GDB can read a description from
915 a local file or over the remote serial protocol.
917 * Vectors of single-byte data use a new integer type which is not
918 automatically displayed as character or string data.
920 * The /s format now works with the print command. It displays
921 arrays of single-byte integers and pointers to single-byte integers
924 * Target descriptions can now describe target-specific registers,
925 for architectures which have implemented the support (currently
926 only ARM, M68K, and MIPS).
928 * GDB and the GDB remote stub, gdbserver, now support the XScale
931 * The GDB remote stub, gdbserver, has been updated to support
932 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
933 has been rewritten to use the standard GDB remote protocol.
935 * GDB can now step into C++ functions which are called through thunks.
937 * GDB for the Cell/B.E. SPU now supports overlay debugging.
939 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
940 layout. It also supports a TextSeg= and DataSeg= response when only
941 segment base addresses (rather than offsets) are available.
943 * The /i format now outputs any trailing branch delay slot instructions
944 immediately following the last instruction within the count specified.
946 * The GDB remote protocol "T" stop reply packet now supports a
947 "library" response. Combined with the new "qXfer:libraries:read"
948 packet, this response allows GDB to debug shared libraries on targets
949 where the operating system manages the list of loaded libraries (e.g.
950 Windows and SymbianOS).
952 * The GDB remote stub, gdbserver, now supports dynamic link libraries
953 (DLLs) on Windows and Windows CE targets.
955 * GDB now supports a faster verification that a .debug file matches its binary
956 according to its build-id signature, if the signature is present.
962 Enable or disable hardware flow control (RTS/CTS) on the serial port
963 when debugging using remote targets.
965 set mem inaccessible-by-default
966 show mem inaccessible-by-default
967 If the target supplies a memory map, for instance via the remote
968 protocol's "qXfer:memory-map:read" packet, setting this variable
969 prevents GDB from accessing memory outside the memory map. This
970 is useful for targets with memory mapped registers or which react
971 badly to accesses of unmapped address space.
973 set breakpoint auto-hw
974 show breakpoint auto-hw
975 If the target supplies a memory map, for instance via the remote
976 protocol's "qXfer:memory-map:read" packet, setting this variable
977 lets GDB use hardware breakpoints automatically for memory regions
978 where it can not use software breakpoints. This covers both the
979 "break" command and internal breakpoints used for other commands
980 including "next" and "finish".
983 catch exception unhandled
984 Stop the program execution when Ada exceptions are raised.
987 Stop the program execution when an Ada assertion failed.
991 Set an alternate system root for target files. This is a more
992 general version of "set solib-absolute-prefix", which is now
993 an alias to "set sysroot".
996 Provide extended SPU facility status information. This set of
997 commands is available only when debugging the Cell/B.E. SPU
1000 * New native configurations
1002 OpenBSD/sh sh*-*openbsd*
1005 unset tdesc filename
1007 Use the specified local file as an XML target description, and do
1008 not query the target for its built-in description.
1012 OpenBSD/sh sh*-*-openbsd*
1013 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1014 Toshiba Media Processor mep-elf
1016 * New remote packets
1019 Ignore the specified signals; pass them directly to the debugged program
1020 without stopping other threads or reporting them to GDB.
1022 qXfer:features:read:
1023 Read an XML target description from the target, which describes its
1028 Read or write contents of an spufs file on the target system. These
1029 packets are available only on the Cell/B.E. SPU architecture.
1031 qXfer:libraries:read:
1032 Report the loaded shared libraries. Combined with new "T" packet
1033 response, this packet allows GDB to debug shared libraries on
1034 targets where the operating system manages the list of loaded
1035 libraries (e.g. Windows and SymbianOS).
1039 Support for these obsolete configurations has been removed.
1047 i[34567]86-*-lynxos*
1048 i[34567]86-*-netware*
1049 i[34567]86-*-sco3.2v5*
1050 i[34567]86-*-sco3.2v4*
1052 i[34567]86-*-sysv4.2*
1055 i[34567]86-*-unixware2*
1056 i[34567]86-*-unixware*
1065 * Other removed features
1072 Various m68k-only ROM monitors.
1079 Various Renesas ROM monitors and debugging interfaces for SH and
1084 Support for a Macraigor serial interface to on-chip debugging.
1085 GDB does not directly support the newer parallel or USB
1090 A debug information format. The predecessor to DWARF 2 and
1091 DWARF 3, which are still supported.
1093 Support for the HP aCC compiler on HP-UX/PA-RISC
1095 SOM-encapsulated symbolic debugging information, automatic
1096 invocation of pxdb, and the aCC custom C++ ABI. This does not
1097 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1098 with aCC can still be debugged on an assembly level.
1100 MIPS ".pdr" sections
1102 A MIPS-specific format used to describe stack frame layout
1103 in debugging information.
1107 GDB could work with an older version of Guile to debug
1108 the interpreter and Scheme programs running in it.
1110 set mips stack-arg-size
1111 set mips saved-gpreg-size
1113 Use "set mips abi" to control parameter passing for MIPS.
1115 *** Changes in GDB 6.6
1120 Cell Broadband Engine SPU spu-elf
1122 * GDB can now be configured as a cross-debugger targeting native Windows
1123 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1124 running on a Windows system over TCP/IP to debug Windows programs.
1126 * The GDB remote stub, gdbserver, has been updated to support Windows and
1127 Cygwin debugging. Both single-threaded and multi-threaded programs are
1130 * The "set trust-readonly-sections" command works again. This command was
1131 broken in GDB 6.3, 6.4, and 6.5.
1133 * The "load" command now supports writing to flash memory, if the remote
1134 stub provides the required support.
1136 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1137 longer requires symbolic debug information (e.g. DWARF-2).
1142 unset substitute-path
1143 show substitute-path
1144 Manage a list of substitution rules that GDB uses to rewrite the name
1145 of the directories where the sources are located. This can be useful
1146 for instance when the sources were moved to a different location
1147 between compilation and debugging.
1151 Print each CLI command as it is executed. Each command is prefixed with
1152 a number of `+' symbols representing the nesting depth.
1153 The source command now has a `-v' option to enable the same feature.
1157 The ARM Demon monitor support (RDP protocol, "target rdp").
1159 Kernel Object Display, an embedded debugging feature which only worked with
1160 an obsolete version of Cisco IOS.
1162 The 'set download-write-size' and 'show download-write-size' commands.
1164 * New remote packets
1167 Tell a stub about GDB client features, and request remote target features.
1168 The first feature implemented is PacketSize, which allows the target to
1169 specify the size of packets it can handle - to minimize the number of
1170 packets required and improve performance when connected to a remote
1174 Fetch an OS auxilliary vector from the remote stub. This packet is a
1175 more efficient replacement for qPart:auxv:read.
1177 qXfer:memory-map:read:
1178 Fetch a memory map from the remote stub, including information about
1179 RAM, ROM, and flash memory devices.
1184 Erase and program a flash memory device.
1186 * Removed remote packets
1189 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1190 used it, and only gdbserver implemented it.
1192 *** Changes in GDB 6.5
1196 Renesas M32C/M16C m32c-elf
1198 Morpho Technologies ms1 ms1-elf
1202 init-if-undefined Initialize a convenience variable, but
1203 only if it doesn't already have a value.
1205 The following commands are presently only implemented for native GNU/Linux:
1207 checkpoint Save a snapshot of the program state.
1209 restart <n> Return the program state to a
1210 previously saved state.
1212 info checkpoints List currently saved checkpoints.
1214 delete-checkpoint <n> Delete a previously saved checkpoint.
1216 set|show detach-on-fork Tell gdb whether to detach from a newly
1217 forked process, or to keep debugging it.
1219 info forks List forks of the user program that
1220 are available to be debugged.
1222 fork <n> Switch to debugging one of several
1223 forks of the user program that are
1224 available to be debugged.
1226 delete-fork <n> Delete a fork from the list of forks
1227 that are available to be debugged (and
1228 kill the forked process).
1230 detach-fork <n> Delete a fork from the list of forks
1231 that are available to be debugged (and
1232 allow the process to continue).
1236 Morpho Technologies ms2 ms1-elf
1238 * Improved Windows host support
1240 GDB now builds as a cross debugger hosted on i686-mingw32, including
1241 native console support, and remote communications using either
1242 network sockets or serial ports.
1244 * Improved Modula-2 language support
1246 GDB can now print most types in the Modula-2 syntax. This includes:
1247 basic types, set types, record types, enumerated types, range types,
1248 pointer types and ARRAY types. Procedure var parameters are correctly
1249 printed and hexadecimal addresses and character constants are also
1250 written in the Modula-2 syntax. Best results can be obtained by using
1251 GNU Modula-2 together with the -gdwarf-2 command line option.
1255 The ARM rdi-share module.
1257 The Netware NLM debug server.
1259 *** Changes in GDB 6.4
1261 * New native configurations
1263 OpenBSD/arm arm*-*-openbsd*
1264 OpenBSD/mips64 mips64-*-openbsd*
1268 Morpho Technologies ms1 ms1-elf
1270 * New command line options
1272 --batch-silent As for --batch, but totally silent.
1273 --return-child-result The debugger will exist with the same value
1274 the child (debugged) program exited with.
1275 --eval-command COMMAND, -ex COMMAND
1276 Execute a single GDB CLI command. This may be
1277 specified multiple times and in conjunction
1278 with the --command (-x) option.
1280 * Deprecated commands removed
1282 The following commands, that were deprecated in 2000, have been
1286 set|show arm disassembly-flavor set|show arm disassembler
1287 othernames set arm disassembler
1288 set|show remotedebug set|show debug remote
1289 set|show archdebug set|show debug arch
1290 set|show eventdebug set|show debug event
1293 * New BSD user-level threads support
1295 It is now possible to debug programs using the user-level threads
1296 library on OpenBSD and FreeBSD. Currently supported (target)
1299 FreeBSD/amd64 x86_64-*-freebsd*
1300 FreeBSD/i386 i386-*-freebsd*
1301 OpenBSD/i386 i386-*-openbsd*
1303 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1304 are not yet supported.
1306 * New support for Matsushita MN10300 w/sim added
1307 (Work in progress). mn10300-elf.
1309 * REMOVED configurations and files
1311 VxWorks and the XDR protocol *-*-vxworks
1312 Motorola MCORE mcore-*-*
1313 National Semiconductor NS32000 ns32k-*-*
1315 * New "set print array-indexes" command
1317 After turning this setting "on", GDB prints the index of each element
1318 when displaying arrays. The default is "off" to preserve the previous
1321 * VAX floating point support
1323 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1325 * User-defined command support
1327 In addition to using $arg0..$arg9 for argument passing, it is now possible
1328 to use $argc to determine now many arguments have been passed. See the
1329 section on user-defined commands in the user manual for more information.
1331 *** Changes in GDB 6.3:
1333 * New command line option
1335 GDB now accepts -l followed by a number to set the timeout for remote
1338 * GDB works with GCC -feliminate-dwarf2-dups
1340 GDB now supports a more compact representation of DWARF-2 debug
1341 information using DW_FORM_ref_addr references. These are produced
1342 by GCC with the option -feliminate-dwarf2-dups and also by some
1343 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1344 to use -feliminate-dwarf2-dups.
1346 * Internationalization
1348 When supported by the host system, GDB will be built with
1349 internationalization (libintl). The task of marking up the sources is
1350 continued, we're looking forward to our first translation.
1354 Initial support for debugging programs compiled with the GNAT
1355 implementation of the Ada programming language has been integrated
1356 into GDB. In this release, support is limited to expression evaluation.
1358 * New native configurations
1360 GNU/Linux/m32r m32r-*-linux-gnu
1364 GDB's remote protocol now includes support for the 'p' packet. This
1365 packet is used to fetch individual registers from a remote inferior.
1367 * END-OF-LIFE registers[] compatibility module
1369 GDB's internal register infrastructure has been completely rewritten.
1370 The new infrastructure making possible the implementation of key new
1371 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1374 GDB 6.3 will be the last release to include the the registers[]
1375 compatibility module that allowed out-of-date configurations to
1376 continue to work. This change directly impacts the following
1386 powerpc bdm protocol
1388 Unless there is activity to revive these configurations, they will be
1389 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1391 * OBSOLETE configurations and files
1393 Configurations that have been declared obsolete in this release have
1394 been commented out. Unless there is activity to revive these
1395 configurations, the next release of GDB will have their sources
1396 permanently REMOVED.
1405 *** Changes in GDB 6.2.1:
1407 * MIPS `break main; run' gave an heuristic-fence-post warning
1409 When attempting to run even a simple program, a warning about
1410 heuristic-fence-post being hit would be reported. This problem has
1413 * MIPS IRIX 'long double' crashed GDB
1415 When examining a long double variable, GDB would get a segmentation
1416 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1417 IRIX long double values).
1421 A bug in the VAX stack code was causing problems with the "next"
1422 command. This problem has been fixed.
1424 *** Changes in GDB 6.2:
1426 * Fix for ``many threads''
1428 On GNU/Linux systems that use the NPTL threads library, a program
1429 rapidly creating and deleting threads would confuse GDB leading to the
1432 ptrace: No such process.
1433 thread_db_get_info: cannot get thread info: generic error
1435 This problem has been fixed.
1437 * "-async" and "-noasync" options removed.
1439 Support for the broken "-noasync" option has been removed (it caused
1442 * New ``start'' command.
1444 This command runs the program until the begining of the main procedure.
1446 * New BSD Kernel Data Access Library (libkvm) interface
1448 Using ``target kvm'' it is now possible to debug kernel core dumps and
1449 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1450 platforms. Currently supported (native-only) configurations are:
1452 FreeBSD/amd64 x86_64-*-freebsd*
1453 FreeBSD/i386 i?86-*-freebsd*
1454 NetBSD/i386 i?86-*-netbsd*
1455 NetBSD/m68k m68*-*-netbsd*
1456 NetBSD/sparc sparc-*-netbsd*
1457 OpenBSD/amd64 x86_64-*-openbsd*
1458 OpenBSD/i386 i?86-*-openbsd*
1459 OpenBSD/m68k m68*-openbsd*
1460 OpenBSD/sparc sparc-*-openbsd*
1462 * Signal trampoline code overhauled
1464 Many generic problems with GDB's signal handling code have been fixed.
1465 These include: backtraces through non-contiguous stacks; recognition
1466 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1467 call; backtrace through a signal trampoline; step into and out of
1468 signal handlers; and single-stepping in the signal trampoline.
1470 Please note that kernel bugs are a limiting factor here. These
1471 features have been shown to work on an s390 GNU/Linux system that
1472 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1474 * Cygwin support for DWARF 2 added.
1476 * New native configurations
1478 GNU/Linux/hppa hppa*-*-linux*
1479 OpenBSD/hppa hppa*-*-openbsd*
1480 OpenBSD/m68k m68*-*-openbsd*
1481 OpenBSD/m88k m88*-*-openbsd*
1482 OpenBSD/powerpc powerpc-*-openbsd*
1483 NetBSD/vax vax-*-netbsd*
1484 OpenBSD/vax vax-*-openbsd*
1486 * END-OF-LIFE frame compatibility module
1488 GDB's internal frame infrastructure has been completely rewritten.
1489 The new infrastructure making it possible to support key new features
1490 including DWARF 2 Call Frame Information. To aid in the task of
1491 migrating old configurations to this new infrastructure, a
1492 compatibility module, that allowed old configurations to continue to
1493 work, was also included.
1495 GDB 6.2 will be the last release to include this frame compatibility
1496 module. This change directly impacts the following configurations:
1506 Unless there is activity to revive these configurations, they will be
1507 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1509 * REMOVED configurations and files
1511 Sun 3, running SunOS 3 m68*-*-sunos3*
1512 Sun 3, running SunOS 4 m68*-*-sunos4*
1513 Sun 2, running SunOS 3 m68000-*-sunos3*
1514 Sun 2, running SunOS 4 m68000-*-sunos4*
1515 Motorola 680x0 running LynxOS m68*-*-lynxos*
1516 AT&T 3b1/Unix pc m68*-att-*
1517 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1518 decstation mips-dec-* mips-little-*
1519 riscos mips-*-riscos* mips-*-sysv*
1520 sonymips mips-sony-*
1521 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1523 *** Changes in GDB 6.1.1:
1525 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1527 The TUI (Text-mode User Interface) is now built as part of a default
1528 GDB configuration. It is enabled by either selecting the TUI with the
1529 command line option "-i=tui" or by running the separate "gdbtui"
1530 program. For more information on the TUI, see the manual "Debugging
1533 * Pending breakpoint support (also included in GDB 6.1)
1535 Support has been added to allow you to specify breakpoints in shared
1536 libraries that have not yet been loaded. If a breakpoint location
1537 cannot be found, and the "breakpoint pending" option is set to auto,
1538 GDB queries you if you wish to make the breakpoint pending on a future
1539 shared-library load. If and when GDB resolves the breakpoint symbol,
1540 the pending breakpoint is removed as one or more regular breakpoints
1543 Pending breakpoints are very useful for GCJ Java debugging.
1545 * Fixed ISO-C build problems
1547 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1548 non ISO-C code that stopped them being built using a more strict ISO-C
1549 compiler (e.g., IBM's C compiler).
1551 * Fixed build problem on IRIX 5
1553 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1554 wasn't able to compile compile on an IRIX 5 system.
1556 * Added execute permission to gdb/gdbserver/configure
1558 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1559 permission. This bug would cause configure to fail on a number of
1560 systems (Solaris, IRIX). Ref: server/519.
1562 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1564 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1565 has been updated to use constant array sizes.
1567 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1569 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1570 its generated DWARF Call Frame Info. This encoding was causing GDB to
1571 panic, that panic has been fixed. Ref: gdb/1628.
1573 * Fixed a problem when examining parameters in shared library code.
1575 When examining parameters in optimized shared library code generated
1576 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1577 not available''. GDB now correctly displays the variable's value.
1579 *** Changes in GDB 6.1:
1581 * Removed --with-mmalloc
1583 Support for the mmalloc memory manager has been removed, as it
1584 conflicted with the internal gdb byte cache.
1586 * Changes in AMD64 configurations
1588 The AMD64 target now includes the %cs and %ss registers. As a result
1589 the AMD64 remote protocol has changed; this affects the floating-point
1590 and SSE registers. If you rely on those registers for your debugging,
1591 you should upgrade gdbserver on the remote side.
1593 * Revised SPARC target
1595 The SPARC target has been completely revised, incorporating the
1596 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1597 support for LynxOS and SunOS 4 has been dropped. Calling functions
1598 from within GDB on operating systems with a non-executable stack
1599 (Solaris, OpenBSD) now works.
1603 GDB has a new C++ demangler which does a better job on the mangled
1604 names generated by current versions of g++. It also runs faster, so
1605 with this and other changes gdb should now start faster on large C++
1608 * DWARF 2 Location Expressions
1610 GDB support for location expressions has been extended to support function
1611 arguments and frame bases. Older versions of GDB could crash when they
1614 * C++ nested types and namespaces
1616 GDB's support for nested types and namespaces in C++ has been
1617 improved, especially if you use the DWARF 2 debugging format. (This
1618 is the default for recent versions of GCC on most platforms.)
1619 Specifically, if you have a class "Inner" defined within a class or
1620 namespace "Outer", then GDB realizes that the class's name is
1621 "Outer::Inner", not simply "Inner". This should greatly reduce the
1622 frequency of complaints about not finding RTTI symbols. In addition,
1623 if you are stopped at inside of a function defined within a namespace,
1624 GDB modifies its name lookup accordingly.
1626 * New native configurations
1628 NetBSD/amd64 x86_64-*-netbsd*
1629 OpenBSD/amd64 x86_64-*-openbsd*
1630 OpenBSD/alpha alpha*-*-openbsd*
1631 OpenBSD/sparc sparc-*-openbsd*
1632 OpenBSD/sparc64 sparc64-*-openbsd*
1634 * New debugging protocols
1636 M32R with SDI protocol m32r-*-elf*
1638 * "set prompt-escape-char" command deleted.
1640 The command "set prompt-escape-char" has been deleted. This command,
1641 and its very obscure effet on GDB's prompt, was never documented,
1642 tested, nor mentioned in the NEWS file.
1644 * OBSOLETE configurations and files
1646 Configurations that have been declared obsolete in this release have
1647 been commented out. Unless there is activity to revive these
1648 configurations, the next release of GDB will have their sources
1649 permanently REMOVED.
1651 Sun 3, running SunOS 3 m68*-*-sunos3*
1652 Sun 3, running SunOS 4 m68*-*-sunos4*
1653 Sun 2, running SunOS 3 m68000-*-sunos3*
1654 Sun 2, running SunOS 4 m68000-*-sunos4*
1655 Motorola 680x0 running LynxOS m68*-*-lynxos*
1656 AT&T 3b1/Unix pc m68*-att-*
1657 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1658 decstation mips-dec-* mips-little-*
1659 riscos mips-*-riscos* mips-*-sysv*
1660 sonymips mips-sony-*
1661 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1663 * REMOVED configurations and files
1665 SGI Irix-4.x mips-sgi-irix4 or iris4
1666 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1667 Z8000 simulator z8k-zilog-none or z8ksim
1668 Matsushita MN10200 w/simulator mn10200-*-*
1669 H8/500 simulator h8500-hitachi-hms or h8500hms
1670 HP/PA running BSD hppa*-*-bsd*
1671 HP/PA running OSF/1 hppa*-*-osf*
1672 HP/PA Pro target hppa*-*-pro*
1673 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1674 386BSD i[3456]86-*-bsd*
1675 Sequent family i[3456]86-sequent-sysv4*
1676 i[3456]86-sequent-sysv*
1677 i[3456]86-sequent-bsd*
1678 SPARC running LynxOS sparc-*-lynxos*
1679 SPARC running SunOS 4 sparc-*-sunos4*
1680 Tsqware Sparclet sparclet-*-*
1681 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1683 *** Changes in GDB 6.0:
1687 Support for debugging the Objective-C programming language has been
1688 integrated into GDB.
1690 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1692 DWARF 2's Call Frame Information makes available compiler generated
1693 information that more exactly describes the program's run-time stack.
1694 By using this information, GDB is able to provide more robust stack
1697 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1698 have been updated to use a new backtrace mechanism which includes
1699 DWARF 2 CFI support.
1703 GDB's remote protocol has been extended to include support for hosted
1704 file I/O (where the remote target uses GDB's file system). See GDB's
1705 remote protocol documentation for details.
1707 * All targets using the new architecture framework.
1709 All of GDB's targets have been updated to use the new internal
1710 architecture framework. The way is now open for future GDB releases
1711 to include cross-architecture native debugging support (i386 on amd64,
1714 * GNU/Linux's Thread Local Storage (TLS)
1716 GDB now includes support for for the GNU/Linux implementation of
1717 per-thread variables.
1719 * GNU/Linux's Native POSIX Thread Library (NPTL)
1721 GDB's thread code has been updated to work with either the new
1722 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1724 * Separate debug info.
1726 GDB, in conjunction with BINUTILS, now supports a mechanism for
1727 automatically loading debug information from a separate file. Instead
1728 of shipping full debug and non-debug versions of system libraries,
1729 system integrators can now instead ship just the stripped libraries
1730 and optional debug files.
1732 * DWARF 2 Location Expressions
1734 DWARF 2 Location Expressions allow the compiler to more completely
1735 describe the location of variables (even in optimized code) to the
1738 GDB now includes preliminary support for location expressions (support
1739 for DW_OP_piece is still missing).
1743 A number of long standing bugs that caused GDB to die while starting a
1744 Java application have been fixed. GDB's Java support is now
1745 considered "useable".
1747 * GNU/Linux support for fork, vfork, and exec.
1749 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1750 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1753 * GDB supports logging output to a file
1755 There are two new commands, "set logging" and "show logging", which can be
1756 used to capture GDB's output to a file.
1758 * The meaning of "detach" has changed for gdbserver
1760 The "detach" command will now resume the application, as documented. To
1761 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1764 * d10v, m68hc11 `regs' command deprecated
1766 The `info registers' command has been updated so that it displays the
1767 registers using a format identical to the old `regs' command.
1771 A new command, "maint set profile on/off", has been added. This command can
1772 be used to enable or disable profiling while running GDB, to profile a
1773 session or a set of commands. In addition there is a new configure switch,
1774 "--enable-profiling", which will cause GDB to be compiled with profiling
1775 data, for more informative profiling results.
1777 * Default MI syntax changed to "mi2".
1779 The default MI (machine interface) syntax, enabled by the command line
1780 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1781 "mi1", can be enabled by specifying the option "-i=mi1".
1783 Support for the original "mi0" syntax (included in GDB 5.0) has been
1786 Fix for gdb/192: removed extraneous space when displaying frame level.
1787 Fix for gdb/672: update changelist is now output in mi list format.
1788 Fix for gdb/702: a -var-assign that updates the value now shows up
1789 in a subsequent -var-update.
1791 * New native configurations.
1793 FreeBSD/amd64 x86_64-*-freebsd*
1795 * Multi-arched targets.
1797 HP/PA HPUX11 hppa*-*-hpux*
1798 Renesas M32R/D w/simulator m32r-*-elf*
1800 * OBSOLETE configurations and files
1802 Configurations that have been declared obsolete in this release have
1803 been commented out. Unless there is activity to revive these
1804 configurations, the next release of GDB will have their sources
1805 permanently REMOVED.
1807 Z8000 simulator z8k-zilog-none or z8ksim
1808 Matsushita MN10200 w/simulator mn10200-*-*
1809 H8/500 simulator h8500-hitachi-hms or h8500hms
1810 HP/PA running BSD hppa*-*-bsd*
1811 HP/PA running OSF/1 hppa*-*-osf*
1812 HP/PA Pro target hppa*-*-pro*
1813 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1814 Sequent family i[3456]86-sequent-sysv4*
1815 i[3456]86-sequent-sysv*
1816 i[3456]86-sequent-bsd*
1817 Tsqware Sparclet sparclet-*-*
1818 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1820 * REMOVED configurations and files
1823 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1824 IBM AIX PS/2 i[3456]86-*-aix
1825 i386 running Mach 3.0 i[3456]86-*-mach3*
1826 i386 running Mach i[3456]86-*-mach*
1827 i386 running OSF/1 i[3456]86-*osf1mk*
1828 HP/Apollo 68k Family m68*-apollo*-sysv*,
1830 m68*-hp-bsd*, m68*-hp-hpux*
1831 Argonaut Risc Chip (ARC) arc-*-*
1832 Mitsubishi D30V d30v-*-*
1833 Fujitsu FR30 fr30-*-elf*
1834 OS/9000 i[34]86-*-os9k
1835 I960 with MON960 i960-*-coff
1837 * MIPS $fp behavior changed
1839 The convenience variable $fp, for the MIPS, now consistently returns
1840 the address of the current frame's base. Previously, depending on the
1841 context, $fp could refer to either $sp or the current frame's base
1842 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1843 The GNU Source-Level Debugger''.
1845 *** Changes in GDB 5.3:
1847 * GNU/Linux shared library multi-threaded performance improved.
1849 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1850 `/proc', in preference to `ptrace' for memory reads. This may result
1851 in an improvement in the start-up time of multi-threaded, shared
1852 library applications when run under GDB. One GDB user writes: ``loads
1853 shared libs like mad''.
1855 * ``gdbserver'' now supports multi-threaded applications on some targets
1857 Support for debugging multi-threaded applications which use
1858 the GNU/Linux LinuxThreads package has been added for
1859 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1860 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1862 * GDB now supports C/C++ preprocessor macros.
1864 GDB now expands preprocessor macro invocations in C/C++ expressions,
1865 and provides various commands for showing macro definitions and how
1868 The new command `macro expand EXPRESSION' expands any macro
1869 invocations in expression, and shows the result.
1871 The new command `show macro MACRO-NAME' shows the definition of the
1872 macro named MACRO-NAME, and where it was defined.
1874 Most compilers don't include information about macros in the debugging
1875 information by default. In GCC 3.1, for example, you need to compile
1876 your program with the options `-gdwarf-2 -g3'. If the macro
1877 information is present in the executable, GDB will read it.
1879 * Multi-arched targets.
1881 DEC Alpha (partial) alpha*-*-*
1882 DEC VAX (partial) vax-*-*
1884 National Semiconductor NS32000 (partial) ns32k-*-*
1885 Motorola 68000 (partial) m68k-*-*
1886 Motorola MCORE mcore-*-*
1890 Fujitsu FRV architecture added by Red Hat frv*-*-*
1893 * New native configurations
1895 Alpha NetBSD alpha*-*-netbsd*
1896 SH NetBSD sh*-*-netbsdelf*
1897 MIPS NetBSD mips*-*-netbsd*
1898 UltraSPARC NetBSD sparc64-*-netbsd*
1900 * OBSOLETE configurations and files
1902 Configurations that have been declared obsolete in this release have
1903 been commented out. Unless there is activity to revive these
1904 configurations, the next release of GDB will have their sources
1905 permanently REMOVED.
1907 Mitsubishi D30V d30v-*-*
1908 OS/9000 i[34]86-*-os9k
1909 IBM AIX PS/2 i[3456]86-*-aix
1910 Fujitsu FR30 fr30-*-elf*
1911 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1912 Argonaut Risc Chip (ARC) arc-*-*
1913 i386 running Mach 3.0 i[3456]86-*-mach3*
1914 i386 running Mach i[3456]86-*-mach*
1915 i386 running OSF/1 i[3456]86-*osf1mk*
1916 HP/Apollo 68k Family m68*-apollo*-sysv*,
1918 m68*-hp-bsd*, m68*-hp-hpux*
1919 I960 with MON960 i960-*-coff
1921 * OBSOLETE languages
1923 CHILL, a Pascal like language used by telecommunications companies.
1925 * REMOVED configurations and files
1927 AMD 29k family via UDI a29k-amd-udi, udi29k
1928 A29K VxWorks a29k-*-vxworks
1929 AMD 29000 embedded, using EBMON a29k-none-none
1930 AMD 29000 embedded with COFF a29k-none-coff
1931 AMD 29000 embedded with a.out a29k-none-aout
1933 testsuite/gdb.hp/gdb.threads-hp/ directory
1935 * New command "set max-user-call-depth <nnn>"
1937 This command allows the user to limit the call depth of user-defined
1938 commands. The default is 1024.
1940 * Changes in FreeBSD/i386 native debugging.
1942 Support for the "generate-core-file" has been added.
1944 * New commands "dump", "append", and "restore".
1946 These commands allow data to be copied from target memory
1947 to a bfd-format or binary file (dump and append), and back
1948 from a file into memory (restore).
1950 * Improved "next/step" support on multi-processor Alpha Tru64.
1952 The previous single-step mechanism could cause unpredictable problems,
1953 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1954 of a software single-step mechanism prevents this.
1956 *** Changes in GDB 5.2.1:
1964 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1965 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1966 Fix, by Joel Brobecker imported from mainline.
1968 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1969 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1970 Fix, by Fred Fish, imported from mainline.
1972 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1973 Surprisingly enough, it works now.
1974 By Michal Ludvig, imported from mainline.
1976 i386 hardware watchpoint support:
1977 avoid misses on second run for some targets.
1978 By Pierre Muller, imported from mainline.
1980 *** Changes in GDB 5.2:
1982 * New command "set trust-readonly-sections on[off]".
1984 This command is a hint that tells gdb that read-only sections
1985 really are read-only (ie. that their contents will not change).
1986 In this mode, gdb will go to the object file rather than the
1987 target to read memory from read-only sections (such as ".text").
1988 This can be a significant performance improvement on some
1989 (notably embedded) targets.
1991 * New command "generate-core-file" (or "gcore").
1993 This new gdb command allows the user to drop a core file of the child
1994 process state at any time. So far it's been implemented only for
1995 GNU/Linux and Solaris, but should be relatively easily ported to other
1996 hosts. Argument is core file name (defaults to core.<pid>).
1998 * New command line option
2000 GDB now accepts --pid or -p followed by a process id.
2002 * Change in command line behavior -- corefiles vs. process ids.
2004 There is a subtle behavior in the way in which GDB handles
2005 command line arguments. The first non-flag argument is always
2006 a program to debug, but the second non-flag argument may either
2007 be a corefile or a process id. Previously, GDB would attempt to
2008 open the second argument as a corefile, and if that failed, would
2009 issue a superfluous error message and then attempt to attach it as
2010 a process. Now, if the second argument begins with a non-digit,
2011 it will be treated as a corefile. If it begins with a digit,
2012 GDB will attempt to attach it as a process, and if no such process
2013 is found, will then attempt to open it as a corefile.
2015 * Changes in ARM configurations.
2017 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2018 configuration is fully multi-arch.
2020 * New native configurations
2022 ARM NetBSD arm*-*-netbsd*
2023 x86 OpenBSD i[3456]86-*-openbsd*
2024 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2025 Sparc64 running FreeBSD sparc64-*-freebsd*
2029 Sanyo XStormy16 xstormy16-elf
2031 * OBSOLETE configurations and files
2033 Configurations that have been declared obsolete in this release have
2034 been commented out. Unless there is activity to revive these
2035 configurations, the next release of GDB will have their sources
2036 permanently REMOVED.
2038 AMD 29k family via UDI a29k-amd-udi, udi29k
2039 A29K VxWorks a29k-*-vxworks
2040 AMD 29000 embedded, using EBMON a29k-none-none
2041 AMD 29000 embedded with COFF a29k-none-coff
2042 AMD 29000 embedded with a.out a29k-none-aout
2044 testsuite/gdb.hp/gdb.threads-hp/ directory
2046 * REMOVED configurations and files
2048 TI TMS320C80 tic80-*-*
2050 PowerPC Solaris powerpcle-*-solaris*
2051 PowerPC Windows NT powerpcle-*-cygwin32
2052 PowerPC Netware powerpc-*-netware*
2053 Harris/CXUX m88k m88*-harris-cxux*
2054 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2055 ns32k-utek-sysv* ns32k-utek-*
2056 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2057 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2058 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2059 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2060 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2062 * Changes to command line processing
2064 The new `--args' feature can be used to specify command-line arguments
2065 for the inferior from gdb's command line.
2067 * Changes to key bindings
2069 There is a new `operate-and-get-next' function bound to `C-o'.
2071 *** Changes in GDB 5.1.1
2073 Fix compile problem on DJGPP.
2075 Fix a problem with floating-point registers on the i386 being
2078 Fix to stop GDB crashing on .debug_str debug info.
2080 Numerous documentation fixes.
2082 Numerous testsuite fixes.
2084 *** Changes in GDB 5.1:
2086 * New native configurations
2088 Alpha FreeBSD alpha*-*-freebsd*
2089 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2090 MIPS GNU/Linux mips*-*-linux*
2091 MIPS SGI Irix 6.x mips*-sgi-irix6*
2092 ia64 AIX ia64-*-aix*
2093 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2097 Motorola 68HC11 and 68HC12 m68hc11-elf
2099 UltraSparc running GNU/Linux sparc64-*-linux*
2101 * OBSOLETE configurations and files
2103 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2104 Harris/CXUX m88k m88*-harris-cxux*
2105 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2106 ns32k-utek-sysv* ns32k-utek-*
2107 TI TMS320C80 tic80-*-*
2109 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2110 PowerPC Solaris powerpcle-*-solaris*
2111 PowerPC Windows NT powerpcle-*-cygwin32
2112 PowerPC Netware powerpc-*-netware*
2113 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2114 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2115 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2116 Apple Macintosh (MPW) host N/A
2118 stuff.c (Program to stuff files into a specially prepared space in kdb)
2119 kdb-start.c (Main loop for the standalone kernel debugger)
2121 Configurations that have been declared obsolete in this release have
2122 been commented out. Unless there is activity to revive these
2123 configurations, the next release of GDB will have their sources
2124 permanently REMOVED.
2126 * REMOVED configurations and files
2128 Altos 3068 m68*-altos-*
2129 Convex c1-*-*, c2-*-*
2131 ARM RISCix arm-*-* (as host)
2135 * GDB has been converted to ISO C.
2137 GDB's source code has been converted to ISO C. In particular, the
2138 sources are fully protoized, and rely on standard headers being
2143 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2145 * The MI enabled by default.
2147 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2148 revised and enabled by default. Packages which use GDB as a debugging
2149 engine behind a UI or another front end are encouraged to switch to
2150 using the GDB/MI interface, instead of the old annotations interface
2151 which is now deprecated.
2153 * Support for debugging Pascal programs.
2155 GDB now includes support for debugging Pascal programs. The following
2156 main features are supported:
2158 - Pascal-specific data types such as sets;
2160 - automatic recognition of Pascal sources based on file-name
2163 - Pascal-style display of data types, variables, and functions;
2165 - a Pascal expression parser.
2167 However, some important features are not yet supported.
2169 - Pascal string operations are not supported at all;
2171 - there are some problems with boolean types;
2173 - Pascal type hexadecimal constants are not supported
2174 because they conflict with the internal variables format;
2176 - support for Pascal objects and classes is not full yet;
2178 - unlike Pascal, GDB is case-sensitive for symbol names.
2180 * Changes in completion.
2182 Commands such as `shell', `run' and `set args', which pass arguments
2183 to inferior programs, now complete on file names, similar to what
2184 users expect at the shell prompt.
2186 Commands which accept locations, such as `disassemble', `print',
2187 `breakpoint', `until', etc. now complete on filenames as well as
2188 program symbols. Thus, if you type "break foob TAB", and the source
2189 files linked into the programs include `foobar.c', that file name will
2190 be one of the candidates for completion. However, file names are not
2191 considered for completion after you typed a colon that delimits a file
2192 name from a name of a function in that file, as in "break foo.c:bar".
2194 `set demangle-style' completes on available demangling styles.
2196 * New platform-independent commands:
2198 It is now possible to define a post-hook for a command as well as a
2199 hook that runs before the command. For more details, see the
2200 documentation of `hookpost' in the GDB manual.
2202 * Changes in GNU/Linux native debugging.
2204 Support for debugging multi-threaded programs has been completely
2205 revised for all platforms except m68k and sparc. You can now debug as
2206 many threads as your system allows you to have.
2208 Attach/detach is supported for multi-threaded programs.
2210 Support for SSE registers was added for x86. This doesn't work for
2211 multi-threaded programs though.
2213 * Changes in MIPS configurations.
2215 Multi-arch support is enabled for all MIPS configurations.
2217 GDB can now be built as native debugger on SGI Irix 6.x systems for
2218 debugging n32 executables. (Debugging 64-bit executables is not yet
2221 * Unified support for hardware watchpoints in all x86 configurations.
2223 Most (if not all) native x86 configurations support hardware-assisted
2224 breakpoints and watchpoints in a unified manner. This support
2225 implements debug register sharing between watchpoints, which allows to
2226 put a virtually infinite number of watchpoints on the same address,
2227 and also supports watching regions up to 16 bytes with several debug
2230 The new maintenance command `maintenance show-debug-regs' toggles
2231 debugging print-outs in functions that insert, remove, and test
2232 watchpoints and hardware breakpoints.
2234 * Changes in the DJGPP native configuration.
2236 New command ``info dos sysinfo'' displays assorted information about
2237 the CPU, OS, memory, and DPMI server.
2239 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2240 display information about segment descriptors stored in GDT, LDT, and
2243 New commands ``info dos pde'' and ``info dos pte'' display entries
2244 from Page Directory and Page Tables (for now works with CWSDPMI only).
2245 New command ``info dos address-pte'' displays the Page Table entry for
2246 a given linear address.
2248 GDB can now pass command lines longer than 126 characters to the
2249 program being debugged (requires an update to the libdbg.a library
2250 which is part of the DJGPP development kit).
2252 DWARF2 debug info is now supported.
2254 It is now possible to `step' and `next' through calls to `longjmp'.
2256 * Changes in documentation.
2258 All GDB documentation was converted to GFDL, the GNU Free
2259 Documentation License.
2261 Tracepoints-related commands are now fully documented in the GDB
2264 TUI, the Text-mode User Interface, is now documented in the manual.
2266 Tracepoints-related commands are now fully documented in the GDB
2269 The "GDB Internals" manual now has an index. It also includes
2270 documentation of `ui_out' functions, GDB coding standards, x86
2271 hardware watchpoints, and memory region attributes.
2273 * GDB's version number moved to ``version.in''
2275 The Makefile variable VERSION has been replaced by the file
2276 ``version.in''. People creating GDB distributions should update the
2277 contents of this file.
2281 GUD support is now a standard part of the EMACS distribution.
2283 *** Changes in GDB 5.0:
2285 * Improved support for debugging FP programs on x86 targets
2287 Unified and much-improved support for debugging floating-point
2288 programs on all x86 targets. In particular, ``info float'' now
2289 displays the FP registers in the same format on all x86 targets, with
2290 greater level of detail.
2292 * Improvements and bugfixes in hardware-assisted watchpoints
2294 It is now possible to watch array elements, struct members, and
2295 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2296 on x86 targets no longer erroneously trigger when the address is
2299 * Improvements in the native DJGPP version of GDB
2301 The distribution now includes all the scripts and auxiliary files
2302 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2303 machines ``out of the box''.
2305 The DJGPP version can now debug programs that use signals. It is
2306 possible to catch signals that happened in the debuggee, deliver
2307 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2308 would kill the program being debugged.) Programs that hook hardware
2309 interrupts (keyboard, timer, etc.) can also be debugged.
2311 It is now possible to debug DJGPP programs that redirect their
2312 standard handles or switch them to raw (as opposed to cooked) mode, or
2313 even close them. The command ``run < foo > bar'' works as expected,
2314 and ``info terminal'' reports useful information about the debuggee's
2315 terminal, including raw/cooked mode, redirection, etc.
2317 The DJGPP version now uses termios functions for console I/O, which
2318 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2321 DOS-style file names with drive letters are now fully supported by
2324 It is now possible to debug DJGPP programs that switch their working
2325 directory. It is also possible to rerun the debuggee any number of
2326 times without restarting GDB; thus, you can use the same setup,
2327 breakpoints, etc. for many debugging sessions.
2329 * New native configurations
2331 ARM GNU/Linux arm*-*-linux*
2332 PowerPC GNU/Linux powerpc-*-linux*
2336 Motorola MCore mcore-*-*
2337 x86 VxWorks i[3456]86-*-vxworks*
2338 PowerPC VxWorks powerpc-*-vxworks*
2339 TI TMS320C80 tic80-*-*
2341 * OBSOLETE configurations
2343 Altos 3068 m68*-altos-*
2344 Convex c1-*-*, c2-*-*
2346 ARM RISCix arm-*-* (as host)
2349 Configurations that have been declared obsolete will be commented out,
2350 but the code will be left in place. If there is no activity to revive
2351 these configurations before the next release of GDB, the sources will
2352 be permanently REMOVED.
2354 * Gould support removed
2356 Support for the Gould PowerNode and NP1 has been removed.
2358 * New features for SVR4
2360 On SVR4 native platforms (such as Solaris), if you attach to a process
2361 without first loading a symbol file, GDB will now attempt to locate and
2362 load symbols from the running process's executable file.
2364 * Many C++ enhancements
2366 C++ support has been greatly improved. Overload resolution now works properly
2367 in almost all cases. RTTI support is on the way.
2369 * Remote targets can connect to a sub-program
2371 A popen(3) style serial-device has been added. This device starts a
2372 sub-process (such as a stand-alone simulator) and then communicates
2373 with that. The sub-program to run is specified using the syntax
2374 ``|<program> <args>'' vis:
2376 (gdb) set remotedebug 1
2377 (gdb) target extended-remote |mn10300-elf-sim program-args
2379 * MIPS 64 remote protocol
2381 A long standing bug in the mips64 remote protocol where by GDB
2382 expected certain 32 bit registers (ex SR) to be transfered as 32
2383 instead of 64 bits has been fixed.
2385 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2386 added to provide backward compatibility with older versions of GDB.
2388 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2390 The command ``set remotebinarydownload'' command has been replaced by
2391 ``set remote X-packet''. Other commands in ``set remote'' family
2392 include ``set remote P-packet''.
2394 * Breakpoint commands accept ranges.
2396 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2397 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2398 ``tracepoint passcount'' also accepts a range of tracepoints.
2400 * ``apropos'' command added.
2402 The ``apropos'' command searches through command names and
2403 documentation strings, printing out matches, making it much easier to
2404 try to find a command that does what you are looking for.
2408 A new machine oriented interface (MI) has been added to GDB. This
2409 interface is designed for debug environments running GDB as a separate
2410 process. This is part of the long term libGDB project. See the
2411 "GDB/MI" chapter of the GDB manual for further information. It can be
2412 enabled by configuring with:
2414 .../configure --enable-gdbmi
2416 *** Changes in GDB-4.18:
2418 * New native configurations
2420 HP-UX 10.20 hppa*-*-hpux10.20
2421 HP-UX 11.x hppa*-*-hpux11.0*
2422 M68K GNU/Linux m68*-*-linux*
2426 Fujitsu FR30 fr30-*-elf*
2427 Intel StrongARM strongarm-*-*
2428 Mitsubishi D30V d30v-*-*
2430 * OBSOLETE configurations
2432 Gould PowerNode, NP1 np1-*-*, pn-*-*
2434 Configurations that have been declared obsolete will be commented out,
2435 but the code will be left in place. If there is no activity to revive
2436 these configurations before the next release of GDB, the sources will
2437 be permanently REMOVED.
2441 As a compatibility experiment, GDB's source files buildsym.h and
2442 buildsym.c have been converted to pure standard C, no longer
2443 containing any K&R compatibility code. We believe that all systems in
2444 use today either come with a standard C compiler, or have a GCC port
2445 available. If this is not true, please report the affected
2446 configuration to bug-gdb@gnu.org immediately. See the README file for
2447 information about getting a standard C compiler if you don't have one
2452 GDB now uses readline 2.2.
2454 * set extension-language
2456 You can now control the mapping between filename extensions and source
2457 languages by using the `set extension-language' command. For instance,
2458 you can ask GDB to treat .c files as C++ by saying
2459 set extension-language .c c++
2460 The command `info extensions' lists all of the recognized extensions
2461 and their associated languages.
2463 * Setting processor type for PowerPC and RS/6000
2465 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2466 you can use the `set processor' command to specify what variant of the
2467 PowerPC family you are debugging. The command
2471 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2472 following PowerPC and RS6000 variants:
2474 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2475 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2477 403GC IBM PowerPC 403GC
2478 505 Motorola PowerPC 505
2479 860 Motorola PowerPC 860 or 850
2480 601 Motorola PowerPC 601
2481 602 Motorola PowerPC 602
2482 603 Motorola/IBM PowerPC 603 or 603e
2483 604 Motorola PowerPC 604 or 604e
2484 750 Motorola/IBM PowerPC 750 or 750
2486 At the moment, this command just tells GDB what to name the
2487 special-purpose processor registers. Since almost all the affected
2488 registers are inaccessible to user-level programs, this command is
2489 only useful for remote debugging in its present form.
2493 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2494 more extensive support for HP-UX. Added features include shared
2495 library support, kernel threads and hardware watchpoints for 11.00,
2496 support for HP's ANSI C and C++ compilers, and a compatibility mode
2497 for xdb and dbx commands.
2501 HP's donation includes the new concept of catchpoints, which is a
2502 generalization of the old catch command. On HP-UX, it is now possible
2503 to catch exec, fork, and vfork, as well as library loading.
2505 This means that the existing catch command has changed; its first
2506 argument now specifies the type of catch to be set up. See the
2507 output of "help catch" for a list of catchpoint types.
2509 * Debugging across forks
2511 On HP-UX, you can choose which process to debug when a fork() happens
2516 HP has donated a curses-based terminal user interface (TUI). To get
2517 it, build with --enable-tui. Although this can be enabled for any
2518 configuration, at present it only works for native HP debugging.
2520 * GDB remote protocol additions
2522 A new protocol packet 'X' that writes binary data is now available.
2523 Default behavior is to try 'X', then drop back to 'M' if the stub
2524 fails to respond. The settable variable `remotebinarydownload'
2525 allows explicit control over the use of 'X'.
2527 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2528 full 64-bit address. The command
2530 set remoteaddresssize 32
2532 can be used to revert to the old behaviour. For existing remote stubs
2533 the change should not be noticed, as the additional address information
2536 In order to assist in debugging stubs, you may use the maintenance
2537 command `packet' to send any text string to the stub. For instance,
2539 maint packet heythere
2541 sends the packet "$heythere#<checksum>". Note that it is very easy to
2542 disrupt a debugging session by sending the wrong packet at the wrong
2545 The compare-sections command allows you to compare section data on the
2546 target to what is in the executable file without uploading or
2547 downloading, by comparing CRC checksums.
2549 * Tracing can collect general expressions
2551 You may now collect general expressions at tracepoints. This requires
2552 further additions to the target-side stub; see tracepoint.c and
2553 doc/agentexpr.texi for further details.
2555 * mask-address variable for Mips
2557 For Mips targets, you may control the zeroing of the upper 32 bits of
2558 a 64-bit address by entering `set mask-address on'. This is mainly
2559 of interest to users of embedded R4xxx and R5xxx processors.
2561 * Higher serial baud rates
2563 GDB's serial code now allows you to specify baud rates 57600, 115200,
2564 230400, and 460800 baud. (Note that your host system may not be able
2565 to achieve all of these rates.)
2569 The i960 configuration now includes an initial implementation of a
2570 builtin simulator, contributed by Jim Wilson.
2573 *** Changes in GDB-4.17:
2575 * New native configurations
2577 Alpha GNU/Linux alpha*-*-linux*
2578 Unixware 2.x i[3456]86-unixware2*
2579 Irix 6.x mips*-sgi-irix6*
2580 PowerPC GNU/Linux powerpc-*-linux*
2581 PowerPC Solaris powerpcle-*-solaris*
2582 Sparc GNU/Linux sparc-*-linux*
2583 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2587 Argonaut Risc Chip (ARC) arc-*-*
2588 Hitachi H8/300S h8300*-*-*
2589 Matsushita MN10200 w/simulator mn10200-*-*
2590 Matsushita MN10300 w/simulator mn10300-*-*
2591 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2592 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2593 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2594 Mitsubishi D10V w/simulator d10v-*-*
2595 Mitsubishi M32R/D w/simulator m32r-*-elf*
2596 Tsqware Sparclet sparclet-*-*
2597 NEC V850 w/simulator v850-*-*
2599 * New debugging protocols
2601 ARM with RDI protocol arm*-*-*
2602 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2603 DDB and LSI variants of PMON protocol mips*-*-*
2604 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2605 PowerPC with SDS protocol powerpc{,le}-*-eabi
2606 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2610 All configurations can now understand and use the DWARF 2 debugging
2611 format. The choice is automatic, if the symbol file contains DWARF 2
2616 GDB now includes basic Java language support. This support is
2617 only useful with Java compilers that produce native machine code.
2619 * solib-absolute-prefix and solib-search-path
2621 For SunOS and SVR4 shared libraries, you may now set the prefix for
2622 loading absolute shared library symbol files, and the search path for
2623 locating non-absolute shared library symbol files.
2625 * Live range splitting
2627 GDB can now effectively debug code for which GCC has performed live
2628 range splitting as part of its optimization. See gdb/doc/LRS for
2629 more details on the expected format of the stabs information.
2633 GDB's support for the GNU Hurd, including thread debugging, has been
2634 updated to work with current versions of the Hurd.
2638 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2639 instruction set. ARM GDB automatically detects when Thumb
2640 instructions are in use, and adjusts disassembly and backtracing
2645 GDB's MIPS target configurations now handle the MIP16 16-bit
2650 GDB now includes support for overlays; if an executable has been
2651 linked such that multiple sections are based at the same address, GDB
2652 will decide which section to use for symbolic info. You can choose to
2653 control the decision manually, using overlay commands, or implement
2654 additional target-side support and use "overlay load-target" to bring
2655 in the overlay mapping. Do "help overlay" for more detail.
2659 The command "info symbol <address>" displays information about
2660 the symbol at the specified address.
2664 The standard remote protocol now includes an extension that allows
2665 asynchronous collection and display of trace data. This requires
2666 extensive support in the target-side debugging stub. Tracing mode
2667 includes a new interaction mode in GDB and new commands: see the
2668 file tracepoint.c for more details.
2672 Configurations for embedded MIPS now include a simulator contributed
2673 by Cygnus Solutions. The simulator supports the instruction sets
2674 of most MIPS variants.
2678 Sparc configurations may now include the ERC32 simulator contributed
2679 by the European Space Agency. The simulator is not built into
2680 Sparc targets by default; configure with --enable-sim to include it.
2684 For target configurations that may include multiple variants of a
2685 basic architecture (such as MIPS and SH), you may now set the
2686 architecture explicitly. "set arch" sets, "info arch" lists
2687 the possible architectures.
2689 *** Changes in GDB-4.16:
2691 * New native configurations
2693 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2694 M68K NetBSD m68k-*-netbsd*
2695 PowerPC AIX 4.x powerpc-*-aix*
2696 PowerPC MacOS powerpc-*-macos*
2697 PowerPC Windows NT powerpcle-*-cygwin32
2698 RS/6000 AIX 4.x rs6000-*-aix4*
2702 ARM with RDP protocol arm-*-*
2703 I960 with MON960 i960-*-coff
2704 MIPS VxWorks mips*-*-vxworks*
2705 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2706 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2708 Matra Sparclet sparclet-*-*
2712 The powerpc-eabi configuration now includes the PSIM simulator,
2713 contributed by Andrew Cagney, with assistance from Mike Meissner.
2714 PSIM is a very elaborate model of the PowerPC, including not only
2715 basic instruction set execution, but also details of execution unit
2716 performance and I/O hardware. See sim/ppc/README for more details.
2720 GDB now works with Solaris 2.5.
2722 * Windows 95/NT native
2724 GDB will now work as a native debugger on Windows 95 and Windows NT.
2725 To build it from source, you must use the "gnu-win32" environment,
2726 which uses a DLL to emulate enough of Unix to run the GNU tools.
2727 Further information, binaries, and sources are available at
2728 ftp.cygnus.com, under pub/gnu-win32.
2730 * dont-repeat command
2732 If a user-defined command includes the command `dont-repeat', then the
2733 command will not be repeated if the user just types return. This is
2734 useful if the command is time-consuming to run, so that accidental
2735 extra keystrokes don't run the same command many times.
2737 * Send break instead of ^C
2739 The standard remote protocol now includes an option to send a break
2740 rather than a ^C to the target in order to interrupt it. By default,
2741 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2743 * Remote protocol timeout
2745 The standard remote protocol includes a new variable `remotetimeout'
2746 that allows you to set the number of seconds before GDB gives up trying
2747 to read from the target. The default value is 2.
2749 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2751 By default GDB will automatically keep track of objects as they are
2752 loaded and unloaded by the dynamic linker. By using the command `set
2753 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2754 when shared library events occur, thus allowing you to set breakpoints
2755 in shared libraries which are explicitly loaded by the inferior.
2757 Note this feature does not work on hpux8. On hpux9 you must link
2758 /usr/lib/end.o into your program. This feature should work
2759 automatically on hpux10.
2761 * Irix 5.x hardware watchpoint support
2763 Irix 5 configurations now support the use of hardware watchpoints.
2765 * Mips protocol "SYN garbage limit"
2767 When debugging a Mips target using the `target mips' protocol, you
2768 may set the number of characters that GDB will ignore by setting
2769 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2770 every character. The default value is 1050.
2772 * Recording and replaying remote debug sessions
2774 If you set `remotelogfile' to the name of a file, gdb will write to it
2775 a recording of a remote debug session. This recording may then be
2776 replayed back to gdb using "gdbreplay". See gdbserver/README for
2777 details. This is useful when you have a problem with GDB while doing
2778 remote debugging; you can make a recording of the session and send it
2779 to someone else, who can then recreate the problem.
2781 * Speedups for remote debugging
2783 GDB includes speedups for downloading and stepping MIPS systems using
2784 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2785 and more efficient S-record downloading.
2787 * Memory use reductions and statistics collection
2789 GDB now uses less memory and reports statistics about memory usage.
2790 Try the `maint print statistics' command, for example.
2792 *** Changes in GDB-4.15:
2794 * Psymtabs for XCOFF
2796 The symbol reader for AIX GDB now uses partial symbol tables. This
2797 can greatly improve startup time, especially for large executables.
2799 * Remote targets use caching
2801 Remote targets now use a data cache to speed up communication with the
2802 remote side. The data cache could lead to incorrect results because
2803 it doesn't know about volatile variables, thus making it impossible to
2804 debug targets which use memory mapped I/O devices. `set remotecache
2805 off' turns the the data cache off.
2807 * Remote targets may have threads
2809 The standard remote protocol now includes support for multiple threads
2810 in the target system, using new protocol commands 'H' and 'T'. See
2811 gdb/remote.c for details.
2815 If GDB is configured with `--enable-netrom', then it will include
2816 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2817 acts as though it is a bank of ROM on the target board, but you can
2818 write into it over the network. GDB's support consists only of
2819 support for fast loading into the emulated ROM; to debug, you must use
2820 another protocol, such as standard remote protocol. The usual
2821 sequence is something like
2823 target nrom <netrom-hostname>
2825 target remote <netrom-hostname>:1235
2829 GDB now includes support for the Apple Macintosh, as a host only. It
2830 may be run as either an MPW tool or as a standalone application, and
2831 it can debug through the serial port. All the usual GDB commands are
2832 available, but to the target command, you must supply "serial" as the
2833 device type instead of "/dev/ttyXX". See mpw-README in the main
2834 directory for more information on how to build. The MPW configuration
2835 scripts */mpw-config.in support only a few targets, and only the
2836 mips-idt-ecoff target has been tested.
2840 GDB configuration now uses autoconf. This is not user-visible,
2841 but does simplify configuration and building.
2845 GDB now supports hpux10.
2847 *** Changes in GDB-4.14:
2849 * New native configurations
2851 x86 FreeBSD i[345]86-*-freebsd
2852 x86 NetBSD i[345]86-*-netbsd
2853 NS32k NetBSD ns32k-*-netbsd
2854 Sparc NetBSD sparc-*-netbsd
2858 A29K VxWorks a29k-*-vxworks
2859 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2860 CPU32 EST-300 emulator m68*-*-est*
2861 PowerPC ELF powerpc-*-elf
2864 * Alpha OSF/1 support for procfs
2866 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2867 possible to attach to running processes. As the mounting of the /proc
2868 filesystem is optional on the Alpha, GDB automatically determines
2869 the availability of /proc during startup. This can lead to problems
2870 if /proc is unmounted after GDB has been started.
2872 * Arguments to user-defined commands
2874 User commands may accept up to 10 arguments separated by whitespace.
2875 Arguments are accessed within the user command via $arg0..$arg9. A
2878 print $arg0 + $arg1 + $arg2
2880 To execute the command use:
2883 Defines the command "adder" which prints the sum of its three arguments.
2884 Note the arguments are text substitutions, so they may reference variables,
2885 use complex expressions, or even perform inferior function calls.
2887 * New `if' and `while' commands
2889 This makes it possible to write more sophisticated user-defined
2890 commands. Both commands take a single argument, which is the
2891 expression to evaluate, and must be followed by the commands to
2892 execute, one per line, if the expression is nonzero, the list being
2893 terminated by the word `end'. The `if' command list may include an
2894 `else' word, which causes the following commands to be executed only
2895 if the expression is zero.
2897 * Fortran source language mode
2899 GDB now includes partial support for Fortran 77. It will recognize
2900 Fortran programs and can evaluate a subset of Fortran expressions, but
2901 variables and functions may not be handled correctly. GDB will work
2902 with G77, but does not yet know much about symbols emitted by other
2905 * Better HPUX support
2907 Most debugging facilities now work on dynamic executables for HPPAs
2908 running hpux9 or later. You can attach to running dynamically linked
2909 processes, but by default the dynamic libraries will be read-only, so
2910 for instance you won't be able to put breakpoints in them. To change
2911 that behavior do the following before running the program:
2917 This will cause the libraries to be mapped private and read-write.
2918 To revert to the normal behavior, do this:
2924 You cannot set breakpoints or examine data in the library until after
2925 the library is loaded if the function/data symbols do not have
2928 GDB can now also read debug symbols produced by the HP C compiler on
2929 HPPAs (sorry, no C++, Fortran or 68k support).
2931 * Target byte order now dynamically selectable
2933 You can choose which byte order to use with a target system, via the
2934 commands "set endian big" and "set endian little", and you can see the
2935 current setting by using "show endian". You can also give the command
2936 "set endian auto", in which case GDB will use the byte order
2937 associated with the executable. Currently, only embedded MIPS
2938 configurations support dynamic selection of target byte order.
2940 * New DOS host serial code
2942 This version uses DPMI interrupts to handle buffered I/O, so you
2943 no longer need to run asynctsr when debugging boards connected to
2946 *** Changes in GDB-4.13:
2948 * New "complete" command
2950 This lists all the possible completions for the rest of the line, if it
2951 were to be given as a command itself. This is intended for use by emacs.
2953 * Trailing space optional in prompt
2955 "set prompt" no longer adds a space for you after the prompt you set. This
2956 allows you to set a prompt which ends in a space or one that does not.
2958 * Breakpoint hit counts
2960 "info break" now displays a count of the number of times the breakpoint
2961 has been hit. This is especially useful in conjunction with "ignore"; you
2962 can ignore a large number of breakpoint hits, look at the breakpoint info
2963 to see how many times the breakpoint was hit, then run again, ignoring one
2964 less than that number, and this will get you quickly to the last hit of
2967 * Ability to stop printing at NULL character
2969 "set print null-stop" will cause GDB to stop printing the characters of
2970 an array when the first NULL is encountered. This is useful when large
2971 arrays actually contain only short strings.
2973 * Shared library breakpoints
2975 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2976 breakpoints in shared libraries before the executable is run.
2978 * Hardware watchpoints
2980 There is a new hardware breakpoint for the watch command for sparclite
2981 targets. See gdb/sparclite/hw_breakpoint.note.
2983 Hardware watchpoints are also now supported under GNU/Linux.
2987 Annotations have been added. These are for use with graphical interfaces,
2988 and are still experimental. Currently only gdba.el uses these.
2990 * Improved Irix 5 support
2992 GDB now works properly with Irix 5.2.
2994 * Improved HPPA support
2996 GDB now works properly with the latest GCC and GAS.
2998 * New native configurations
3000 Sequent PTX4 i[34]86-sequent-ptx4
3001 HPPA running OSF/1 hppa*-*-osf*
3002 Atari TT running SVR4 m68*-*-sysv4*
3003 RS/6000 LynxOS rs6000-*-lynxos*
3007 OS/9000 i[34]86-*-os9k
3008 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3011 * Hitachi SH7000 and E7000-PC ICE support
3013 There is now support for communicating with the Hitachi E7000-PC ICE.
3014 This is available automatically when GDB is configured for the SH.
3018 As usual, a variety of small fixes and improvements, both generic
3019 and configuration-specific. See the ChangeLog for more detail.
3021 *** Changes in GDB-4.12:
3023 * Irix 5 is now supported
3027 GDB-4.12 on the HPPA has a number of changes which make it unable
3028 to debug the output from the currently released versions of GCC and
3029 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3030 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3031 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3034 *** Changes in GDB-4.11:
3036 * User visible changes:
3040 The "set remotedebug" option is now consistent between the mips remote
3041 target, remote targets using the gdb-specific protocol, UDI (AMD's
3042 debug protocol for the 29k) and the 88k bug monitor. It is now an
3043 integer specifying a debug level (normally 0 or 1, but 2 means more
3044 debugging info for the mips target).
3046 * DEC Alpha native support
3048 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3049 debug info, but GDB works fairly well with the DEC compiler and should
3050 work with a future GCC release. See the README file for a few
3051 Alpha-specific notes.
3053 * Preliminary thread implementation
3055 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3057 * LynxOS native and target support for 386
3059 This release has been hosted on LynxOS 2.2, and also can be configured
3060 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3063 * Improvements in C++ mangling/demangling.
3065 This release has much better g++ debugging, specifically in name
3066 mangling/demangling, virtual function calls, print virtual table,
3067 call methods, ...etc.
3069 *** Changes in GDB-4.10:
3071 * User visible changes:
3073 Remote debugging using the GDB-specific (`target remote') protocol now
3074 supports the `load' command. This is only useful if you have some
3075 other way of getting the stub to the target system, and you can put it
3076 somewhere in memory where it won't get clobbered by the download.
3078 Filename completion now works.
3080 When run under emacs mode, the "info line" command now causes the
3081 arrow to point to the line specified. Also, "info line" prints
3082 addresses in symbolic form (as well as hex).
3084 All vxworks based targets now support a user settable option, called
3085 vxworks-timeout. This option represents the number of seconds gdb
3086 should wait for responses to rpc's. You might want to use this if
3087 your vxworks target is, perhaps, a slow software simulator or happens
3088 to be on the far side of a thin network line.
3092 This release contains support for using a DEC alpha as a GDB host for
3093 cross debugging. Native alpha debugging is not supported yet.
3096 *** Changes in GDB-4.9:
3100 This is the first GDB release which is accompanied by a matching testsuite.
3101 The testsuite requires installation of dejagnu, which should be available
3102 via ftp from most sites that carry GNU software.
3106 'Cfront' style demangling has had its name changed to 'ARM' style, to
3107 emphasize that it was written from the specifications in the C++ Annotated
3108 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3109 disclaimers, it still generated too much confusion with users attempting to
3110 use gdb with AT&T cfront.
3114 GDB now uses a standard remote interface to a simulator library.
3115 So far, the library contains simulators for the Zilog Z8001/2, the
3116 Hitachi H8/300, H8/500 and Super-H.
3118 * New targets supported
3120 H8/300 simulator h8300-hitachi-hms or h8300hms
3121 H8/500 simulator h8500-hitachi-hms or h8500hms
3122 SH simulator sh-hitachi-hms or sh
3123 Z8000 simulator z8k-zilog-none or z8ksim
3124 IDT MIPS board over serial line mips-idt-ecoff
3126 Cross-debugging to GO32 targets is supported. It requires a custom
3127 version of the i386-stub.c module which is integrated with the
3128 GO32 memory extender.
3130 * New remote protocols
3132 MIPS remote debugging protocol.
3134 * New source languages supported
3136 This version includes preliminary support for Chill, a Pascal like language
3137 used by telecommunications companies. Chill support is also being integrated
3138 into the GNU compiler, but we don't know when it will be publically available.
3141 *** Changes in GDB-4.8:
3143 * HP Precision Architecture supported
3145 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3146 version of this support was available as a set of patches from the
3147 University of Utah. GDB does not support debugging of programs
3148 compiled with the HP compiler, because HP will not document their file
3149 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3150 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3152 Many problems in the preliminary version have been fixed.
3154 * Faster and better demangling
3156 We have improved template demangling and fixed numerous bugs in the GNU style
3157 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3158 character types (wchar_t) are now supported. Demangling of each symbol is now
3159 only done once, and is cached when the symbol table for a file is read in.
3160 This results in a small increase in memory usage for C programs, a moderate
3161 increase in memory usage for C++ programs, and a fantastic speedup in
3164 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3165 from the specifications in the Annotated Reference Manual, which AT&T's
3166 compiler does not actually implement.
3168 * G++ multiple inheritance compiler problem
3170 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3171 inheritance lattices was reworked to properly discover ambiguities. We
3172 recently found an example which causes this new algorithm to fail in a
3173 very subtle way, producing bad debug information for those classes.
3174 The file 'gcc.patch' (in this directory) can be applied to gcc to
3175 circumvent the problem. A future GCC release will contain a complete
3178 The previous G++ debug info problem (mentioned below for the gdb-4.7
3179 release) is fixed in gcc version 2.3.2.
3181 * Improved configure script
3183 The `configure' script will now attempt to guess your system type if
3184 you don't supply a host system type. The old scheme of supplying a
3185 host system triplet is preferable over using this. All the magic is
3186 done in the new `config.guess' script. Examine it for details.
3188 We have also brought our configure script much more in line with the FSF's
3189 version. It now supports the --with-xxx options. In particular,
3190 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3191 The resulting GDB will not be able to read arbitrary object file formats --
3192 only the format ``expected'' to be used on the configured target system.
3193 We hope to make this the default in a future release.
3195 * Documentation improvements
3197 There's new internal documentation on how to modify GDB, and how to
3198 produce clean changes to the code. We implore people to read it
3199 before submitting changes.
3201 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3202 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3203 `info' files are also provided. To build `info' files from scratch,
3204 you will need the latest `makeinfo' release, which will be available in
3205 a future texinfo-X.Y release.
3207 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3208 We're not sure exactly which versions have this problem, but it has
3209 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3210 or better. If that isn't possible, there is a patch in
3211 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3212 around this problem.
3216 GDB now supports array constants that can be used in expressions typed in by
3217 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3218 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3221 The new directory `gdb/sparclite' contains a program that demonstrates
3222 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3224 * New native hosts supported
3226 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3227 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3229 * New targets supported
3231 AMD 29k family via UDI a29k-amd-udi or udi29k
3233 * New file formats supported
3235 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3236 HPUX core files, and SCO 3.2v2 core files.
3240 Attaching to processes now works again; thanks for the many bug reports.
3242 We have also stomped on a bunch of core dumps caused by
3243 printf_filtered("%s") problems.
3245 We eliminated a copyright problem on the rpc and ptrace header files
3246 for VxWorks, which was discovered at the last minute during the 4.7
3247 release. You should now be able to build a VxWorks GDB.
3249 You can now interrupt gdb while an attached process is running. This
3250 will cause the attached process to stop, and give control back to GDB.
3252 We fixed problems caused by using too many file descriptors
3253 for reading symbols from object files and libraries. This was
3254 especially a problem for programs that used many (~100) shared
3257 The `step' command now only enters a subroutine if there is line number
3258 information for the subroutine. Otherwise it acts like the `next'
3259 command. Previously, `step' would enter subroutines if there was
3260 any debugging information about the routine. This avoids problems
3261 when using `cc -g1' on MIPS machines.
3263 * Internal improvements
3265 GDB's internal interfaces have been improved to make it easier to support
3266 debugging of multiple languages in the future.
3268 GDB now uses a common structure for symbol information internally.
3269 Minimal symbols (derived from linkage symbols in object files), partial
3270 symbols (from a quick scan of debug information), and full symbols
3271 contain a common subset of information, making it easier to write
3272 shared code that handles any of them.
3274 * New command line options
3276 We now accept --silent as an alias for --quiet.
3280 The memory-mapped-malloc library is now licensed under the GNU Library
3281 General Public License.
3283 *** Changes in GDB-4.7:
3285 * Host/native/target split
3287 GDB has had some major internal surgery to untangle the support for
3288 hosts and remote targets. Now, when you configure GDB for a remote
3289 target, it will no longer load in all of the support for debugging
3290 local programs on the host. When fully completed and tested, this will
3291 ensure that arbitrary host/target combinations are possible.
3293 The primary conceptual shift is to separate the non-portable code in
3294 GDB into three categories. Host specific code is required any time GDB
3295 is compiled on that host, regardless of the target. Target specific
3296 code relates to the peculiarities of the target, but can be compiled on
3297 any host. Native specific code is everything else: it can only be
3298 built when the host and target are the same system. Child process
3299 handling and core file support are two common `native' examples.
3301 GDB's use of /proc for controlling Unix child processes is now cleaner.
3302 It has been split out into a single module under the `target_ops' vector,
3303 plus two native-dependent functions for each system that uses /proc.
3305 * New hosts supported
3307 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3308 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3309 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3311 * New targets supported
3313 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3314 68030 and CPU32 m68030-*-*, m68332-*-*
3316 * New native hosts supported
3318 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3319 (386bsd is not well tested yet)
3320 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3322 * New file formats supported
3324 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3325 supports reading of `a.out.adobe' object files, which are an a.out
3326 format extended with minimal information about multiple sections.
3330 `show copying' is the same as the old `info copying'.
3331 `show warranty' is the same as `info warrantee'.
3332 These were renamed for consistency. The old commands continue to work.
3334 `info handle' is a new alias for `info signals'.
3336 You can now define pre-command hooks, which attach arbitrary command
3337 scripts to any command. The commands in the hook will be executed
3338 prior to the user's command. You can also create a hook which will be
3339 executed whenever the program stops. See gdb.texinfo.
3343 We now deal with Cfront style name mangling, and can even extract type
3344 info from mangled symbols. GDB can automatically figure out which
3345 symbol mangling style your C++ compiler uses.
3347 Calling of methods and virtual functions has been improved as well.
3351 The crash that occured when debugging Sun Ansi-C compiled binaries is
3352 fixed. This was due to mishandling of the extra N_SO stabs output
3355 We also finally got Ultrix 4.2 running in house, and fixed core file
3356 support, with help from a dozen people on the net.
3358 John M. Farrell discovered that the reason that single-stepping was so
3359 slow on all of the Mips based platforms (primarily SGI and DEC) was
3360 that we were trying to demangle and lookup a symbol used for internal
3361 purposes on every instruction that was being stepped through. Changing
3362 the name of that symbol so that it couldn't be mistaken for a C++
3363 mangled symbol sped things up a great deal.
3365 Rich Pixley sped up symbol lookups in general by getting much smarter
3366 about when C++ symbol mangling is necessary. This should make symbol
3367 completion (TAB on the command line) much faster. It's not as fast as
3368 we'd like, but it's significantly faster than gdb-4.6.
3372 A new user controllable variable 'call_scratch_address' can
3373 specify the location of a scratch area to be used when GDB
3374 calls a function in the target. This is necessary because the
3375 usual method of putting the scratch area on the stack does not work
3376 in systems that have separate instruction and data spaces.
3378 We integrated changes to support the 29k UDI (Universal Debugger
3379 Interface), but discovered at the last minute that we didn't have all
3380 of the appropriate copyright paperwork. We are working with AMD to
3381 resolve this, and hope to have it available soon.
3385 We have sped up the remote serial line protocol, especially for targets
3386 with lots of registers. It now supports a new `expedited status' ('T')
3387 message which can be used in place of the existing 'S' status message.
3388 This allows the remote stub to send only the registers that GDB
3389 needs to make a quick decision about single-stepping or conditional
3390 breakpoints, eliminating the need to fetch the entire register set for
3391 each instruction being stepped through.
3393 The GDB remote serial protocol now implements a write-through cache for
3394 registers, only re-reading the registers if the target has run.
3396 There is also a new remote serial stub for SPARC processors. You can
3397 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3398 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3399 processor with a serial port.
3403 Configure.in files have become much easier to read and modify. A new
3404 `table driven' format makes it more obvious what configurations are
3405 supported, and what files each one uses.
3409 There is a new opcodes library which will eventually contain all of the
3410 disassembly routines and opcode tables. At present, it only contains
3411 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3412 disassembler (binutils/objdump) to share these routines.
3414 The libiberty library is now copylefted under the GNU Library General
3415 Public License. This allows more liberal use, and was done so libg++
3416 can use it. This makes no difference to GDB, since the Library License
3417 grants all the rights from the General Public License.
3421 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3422 reference to the stabs symbol info used by the debugger. It is (as far
3423 as we know) the only published document on this fascinating topic. We
3424 encourage you to read it, compare it to the stabs information on your
3425 system, and send improvements on the document in general (to
3426 bug-gdb@prep.ai.mit.edu).
3428 And, of course, many bugs have been fixed.
3431 *** Changes in GDB-4.6:
3433 * Better support for C++ function names
3435 GDB now accepts as input the "demangled form" of C++ overloaded function
3436 names and member function names, and can do command completion on such names
3437 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3438 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3439 Make use of command completion, it is your friend.
3441 GDB also now accepts a variety of C++ mangled symbol formats. They are
3442 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3443 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3444 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3445 for the list of formats.
3447 * G++ symbol mangling problem
3449 Recent versions of gcc have a bug in how they emit debugging information for
3450 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3451 directory) can be applied to gcc to fix the problem. Alternatively, if you
3452 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3453 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3454 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3457 * New 'maintenance' command
3459 All of the commands related to hacking GDB internals have been moved out of
3460 the main command set, and now live behind the 'maintenance' command. This
3461 can also be abbreviated as 'mt'. The following changes were made:
3463 dump-me -> maintenance dump-me
3464 info all-breakpoints -> maintenance info breakpoints
3465 printmsyms -> maintenance print msyms
3466 printobjfiles -> maintenance print objfiles
3467 printpsyms -> maintenance print psymbols
3468 printsyms -> maintenance print symbols
3470 The following commands are new:
3472 maintenance demangle Call internal GDB demangler routine to
3473 demangle a C++ link name and prints the result.
3474 maintenance print type Print a type chain for a given symbol
3476 * Change to .gdbinit file processing
3478 We now read the $HOME/.gdbinit file before processing the argv arguments
3479 (e.g. reading symbol files or core files). This allows global parameters to
3480 be set, which will apply during the symbol reading. The ./.gdbinit is still
3481 read after argv processing.
3483 * New hosts supported
3485 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3487 GNU/Linux support i386-unknown-linux or linux
3489 We are also including code to support the HP/PA running BSD and HPUX. This
3490 is almost guaranteed not to work, as we didn't have time to test or build it
3491 for this release. We are including it so that the more adventurous (or
3492 masochistic) of you can play with it. We also had major problems with the
3493 fact that the compiler that we got from HP doesn't support the -g option.
3496 * New targets supported
3498 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3500 * More smarts about finding #include files
3502 GDB now remembers the compilation directory for all include files, and for
3503 all files from which C is generated (like yacc and lex sources). This
3504 greatly improves GDB's ability to find yacc/lex sources, and include files,
3505 especially if you are debugging your program from a directory different from
3506 the one that contains your sources.
3508 We also fixed a bug which caused difficulty with listing and setting
3509 breakpoints in include files which contain C code. (In the past, you had to
3510 try twice in order to list an include file that you hadn't looked at before.)
3512 * Interesting infernals change
3514 GDB now deals with arbitrary numbers of sections, where the symbols for each
3515 section must be relocated relative to that section's landing place in the
3516 target's address space. This work was needed to support ELF with embedded
3517 stabs used by Solaris-2.0.
3519 * Bug fixes (of course!)
3521 There have been loads of fixes for the following things:
3522 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3523 i960, stabs, DOS(GO32), procfs, etc...
3525 See the ChangeLog for details.
3527 *** Changes in GDB-4.5:
3529 * New machines supported (host and target)
3531 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3533 SGI Irix-4.x mips-sgi-irix4 or iris4
3535 * New malloc package
3537 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3538 Mmalloc is capable of handling mutiple heaps of memory. It is also
3539 capable of saving a heap to a file, and then mapping it back in later.
3540 This can be used to greatly speedup the startup of GDB by using a
3541 pre-parsed symbol table which lives in a mmalloc managed heap. For
3542 more details, please read mmalloc/mmalloc.texi.
3546 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3547 'help info proc' for details.
3549 * MIPS ecoff symbol table format
3551 The code that reads MIPS symbol table format is now supported on all hosts.
3552 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3555 * File name changes for MS-DOS
3557 Many files in the config directories have been renamed to make it easier to
3558 support GDB on MS-DOSe systems (which have very restrictive file name
3559 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3560 environment) is close to working but has some remaining problems. Note
3561 that debugging of DOS programs is not supported, due to limitations
3562 in the ``operating system'', but it can be used to host cross-debugging.
3564 * Cross byte order fixes
3566 Many fixes have been made to support cross debugging of Sparc and MIPS
3567 targets from hosts whose byte order differs.
3569 * New -mapped and -readnow options
3571 If memory-mapped files are available on your system through the 'mmap'
3572 system call, you can use the -mapped option on the `file' or
3573 `symbol-file' commands to cause GDB to write the symbols from your
3574 program into a reusable file. If the program you are debugging is
3575 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3576 Future GDB debugging sessions will notice the presence of this file,
3577 and will quickly map in symbol information from it, rather than reading
3578 the symbol table from the executable program. Using the '-mapped'
3579 option in a GDB `file' or `symbol-file' command has the same effect as
3580 starting GDB with the '-mapped' command-line option.
3582 You can cause GDB to read the entire symbol table immediately by using
3583 the '-readnow' option with any of the commands that load symbol table
3584 information (or on the GDB command line). This makes the command
3585 slower, but makes future operations faster.
3587 The -mapped and -readnow options are typically combined in order to
3588 build a `fred.syms' file that contains complete symbol information.
3589 A simple GDB invocation to do nothing but build a `.syms' file for future
3592 gdb -batch -nx -mapped -readnow programname
3594 The `.syms' file is specific to the host machine on which GDB is run.
3595 It holds an exact image of GDB's internal symbol table. It cannot be
3596 shared across multiple host platforms.
3598 * longjmp() handling
3600 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3601 siglongjmp() without losing control. This feature has not yet been ported to
3602 all systems. It currently works on many 386 platforms, all MIPS-based
3603 platforms (SGI, DECstation, etc), and Sun3/4.
3607 Preliminary work has been put in to support the new Solaris OS from Sun. At
3608 this time, it can control and debug processes, but it is not capable of
3613 As always, many many bug fixes. The major areas were with g++, and mipsread.
3614 People using the MIPS-based platforms should experience fewer mysterious
3615 crashes and trashed symbol tables.
3617 *** Changes in GDB-4.4:
3619 * New machines supported (host and target)
3621 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3623 BSD Reno on Vax vax-dec-bsd
3624 Ultrix on Vax vax-dec-ultrix
3626 * New machines supported (target)
3628 AMD 29000 embedded, using EBMON a29k-none-none
3632 GDB continues to improve its handling of C++. `References' work better.
3633 The demangler has also been improved, and now deals with symbols mangled as
3634 per the Annotated C++ Reference Guide.
3636 GDB also now handles `stabs' symbol information embedded in MIPS
3637 `ecoff' symbol tables. Since the ecoff format was not easily
3638 extensible to handle new languages such as C++, this appeared to be a
3639 good way to put C++ debugging info into MIPS binaries. This option
3640 will be supported in the GNU C compiler, version 2, when it is
3643 * New features for SVR4
3645 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3646 shared libraries. Debugging dynamically linked programs should present
3647 only minor differences from debugging statically linked programs.
3649 The `info proc' command will print out information about any process
3650 on an SVR4 system (including the one you are debugging). At the moment,
3651 it prints the address mappings of the process.
3653 If you bring up GDB on another SVR4 system, please send mail to
3654 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3656 * Better dynamic linking support in SunOS
3658 Reading symbols from shared libraries which contain debugging symbols
3659 now works properly. However, there remain issues such as automatic
3660 skipping of `transfer vector' code during function calls, which
3661 make it harder to debug code in a shared library, than to debug the
3662 same code linked statically.
3666 GDB is now using the latest `getopt' routines from the FSF. This
3667 version accepts the -- prefix for options with long names. GDB will
3668 continue to accept the old forms (-option and +option) as well.
3669 Various single letter abbreviations for options have been explicity
3670 added to the option table so that they won't get overshadowed in the
3671 future by other options that begin with the same letter.
3675 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3676 Many assorted bugs have been handled. Many more remain to be handled.
3677 See the various ChangeLog files (primarily in gdb and bfd) for details.
3680 *** Changes in GDB-4.3:
3682 * New machines supported (host and target)
3684 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3685 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3686 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3688 * Almost SCO Unix support
3690 We had hoped to support:
3691 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3692 (except for core file support), but we discovered very late in the release
3693 that it has problems with process groups that render gdb unusable. Sorry
3694 about that. I encourage people to fix it and post the fixes.
3696 * Preliminary ELF and DWARF support
3698 GDB can read ELF object files on System V Release 4, and can handle
3699 debugging records for C, in DWARF format, in ELF files. This support
3700 is preliminary. If you bring up GDB on another SVR4 system, please
3701 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3706 GDB now uses the latest `readline' library. One user-visible change
3707 is that two tabs will list possible command completions, which previously
3708 required typing M-? (meta-question mark, or ESC ?).
3712 The `stepi' bug that many of you noticed has been squashed.
3713 Many bugs in C++ have been handled. Many more remain to be handled.
3714 See the various ChangeLog files (primarily in gdb and bfd) for details.
3716 * State of the MIPS world (in case you wondered):
3718 GDB can understand the symbol tables emitted by the compilers
3719 supplied by most vendors of MIPS-based machines, including DEC. These
3720 symbol tables are in a format that essentially nobody else uses.
3722 Some versions of gcc come with an assembler post-processor called
3723 mips-tfile. This program is required if you want to do source-level
3724 debugging of gcc-compiled programs. I believe FSF does not ship
3725 mips-tfile with gcc version 1, but it will eventually come with gcc
3728 Debugging of g++ output remains a problem. g++ version 1.xx does not
3729 really support it at all. (If you're lucky, you should be able to get
3730 line numbers and stack traces to work, but no parameters or local
3731 variables.) With some work it should be possible to improve the
3734 When gcc version 2 is released, you will have somewhat better luck.
3735 However, even then you will get confusing results for inheritance and
3738 We will eventually provide full debugging of g++ output on
3739 DECstations. This will probably involve some kind of stabs-in-ecoff
3740 encapulation, but the details have not been worked out yet.
3743 *** Changes in GDB-4.2:
3745 * Improved configuration
3747 Only one copy of `configure' exists now, and it is not self-modifying.
3748 Porting BFD is simpler.
3752 The `step' and `next' commands now only stop at the first instruction
3753 of a source line. This prevents the multiple stops that used to occur
3754 in switch statements, for-loops, etc. `Step' continues to stop if a
3755 function that has debugging information is called within the line.
3759 Lots of small bugs fixed. More remain.
3761 * New host supported (not target)
3763 Intel 386 PC clone running Mach i386-none-mach
3766 *** Changes in GDB-4.1:
3768 * Multiple source language support
3770 GDB now has internal scaffolding to handle several source languages.
3771 It determines the type of each source file from its filename extension,
3772 and will switch expression parsing and number formatting to match the
3773 language of the function in the currently selected stack frame.
3774 You can also specifically set the language to be used, with
3775 `set language c' or `set language modula-2'.
3779 GDB now has preliminary support for the GNU Modula-2 compiler,
3780 currently under development at the State University of New York at
3781 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3782 continue through the fall of 1991 and into 1992.
3784 Other Modula-2 compilers are currently not supported, and attempting to
3785 debug programs compiled with them will likely result in an error as the
3786 symbol table is read. Feel free to work on it, though!
3788 There are hooks in GDB for strict type checking and range checking,
3789 in the `Modula-2 philosophy', but they do not currently work.
3793 GDB can now write to executable and core files (e.g. patch
3794 a variable's value). You must turn this switch on, specify
3795 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3796 by assigning a new value to a variable. Modifications take
3799 * Automatic SunOS shared library reading
3801 When you run your program, GDB automatically determines where its
3802 shared libraries (if any) have been loaded, and reads their symbols.
3803 The `share' command is no longer needed. This also works when
3804 examining core files.
3808 You can specify the number of lines that the `list' command shows.
3811 * New machines supported (host and target)
3813 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3814 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3815 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3817 * New hosts supported (not targets)
3819 IBM RT/PC: romp-ibm-aix or rtpc
3821 * New targets supported (not hosts)
3823 AMD 29000 embedded with COFF a29k-none-coff
3824 AMD 29000 embedded with a.out a29k-none-aout
3825 Ultracomputer remote kernel debug a29k-nyu-kern
3827 * New remote interfaces
3833 *** Changes in GDB-4.0:
3837 Wide output is wrapped at good places to make the output more readable.
3839 Gdb now supports cross-debugging from a host machine of one type to a
3840 target machine of another type. Communication with the target system
3841 is over serial lines. The ``target'' command handles connecting to the
3842 remote system; the ``load'' command will download a program into the
3843 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3844 also supports debugging of realtime processes running under VxWorks,
3845 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3846 stub on the target system.
3848 New CPUs supported include the AMD 29000 and Intel 960.
3850 GDB now reads object files and symbol tables via a ``binary file''
3851 library, which allows a single copy of GDB to debug programs of multiple
3852 object file types such as a.out and coff.
3854 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3855 refcard.dvi and refcard.ps are available to format it).
3858 * Control-Variable user interface simplified
3860 All variables that control the operation of the debugger can be set
3861 by the ``set'' command, and displayed by the ``show'' command.
3863 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3864 ``Show prompt'' produces the response:
3865 Gdb's prompt is new-gdb=>.
3867 What follows are the NEW set commands. The command ``help set'' will
3868 print a complete list of old and new set commands. ``help set FOO''
3869 will give a longer description of the variable FOO. ``show'' will show
3870 all of the variable descriptions and their current settings.
3872 confirm on/off: Enables warning questions for operations that are
3873 hard to recover from, e.g. rerunning the program while
3874 it is already running. Default is ON.
3876 editing on/off: Enables EMACS style command line editing
3877 of input. Previous lines can be recalled with
3878 control-P, the current line can be edited with control-B,
3879 you can search for commands with control-R, etc.
3882 history filename NAME: NAME is where the gdb command history
3883 will be stored. The default is .gdb_history,
3884 or the value of the environment variable
3887 history size N: The size, in commands, of the command history. The
3888 default is 256, or the value of the environment variable
3891 history save on/off: If this value is set to ON, the history file will
3892 be saved after exiting gdb. If set to OFF, the
3893 file will not be saved. The default is OFF.
3895 history expansion on/off: If this value is set to ON, then csh-like
3896 history expansion will be performed on
3897 command line input. The default is OFF.
3899 radix N: Sets the default radix for input and output. It can be set
3900 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3901 in the current radix, so "set radix 10" is always a no-op.
3903 height N: This integer value is the number of lines on a page. Default
3904 is 24, the current `stty rows'' setting, or the ``li#''
3905 setting from the termcap entry matching the environment
3908 width N: This integer value is the number of characters on a line.
3909 Default is 80, the current `stty cols'' setting, or the ``co#''
3910 setting from the termcap entry matching the environment
3913 Note: ``set screensize'' is obsolete. Use ``set height'' and
3914 ``set width'' instead.
3916 print address on/off: Print memory addresses in various command displays,
3917 such as stack traces and structure values. Gdb looks
3918 more ``symbolic'' if you turn this off; it looks more
3919 ``machine level'' with it on. Default is ON.
3921 print array on/off: Prettyprint arrays. New convenient format! Default
3924 print demangle on/off: Print C++ symbols in "source" form if on,
3927 print asm-demangle on/off: Same, for assembler level printouts
3930 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3933 * Support for Epoch Environment.
3935 The epoch environment is a version of Emacs v18 with windowing. One
3936 new command, ``inspect'', is identical to ``print'', except that if you
3937 are running in the epoch environment, the value is printed in its own
3941 * Support for Shared Libraries
3943 GDB can now debug programs and core files that use SunOS shared libraries.
3944 Symbols from a shared library cannot be referenced
3945 before the shared library has been linked with the program (this
3946 happens after you type ``run'' and before the function main() is entered).
3947 At any time after this linking (including when examining core files
3948 from dynamically linked programs), gdb reads the symbols from each
3949 shared library when you type the ``sharedlibrary'' command.
3950 It can be abbreviated ``share''.
3952 sharedlibrary REGEXP: Load shared object library symbols for files
3953 matching a unix regular expression. No argument
3954 indicates to load symbols for all shared libraries.
3956 info sharedlibrary: Status of loaded shared libraries.
3961 A watchpoint stops execution of a program whenever the value of an
3962 expression changes. Checking for this slows down execution
3963 tremendously whenever you are in the scope of the expression, but is
3964 quite useful for catching tough ``bit-spreader'' or pointer misuse
3965 problems. Some machines such as the 386 have hardware for doing this
3966 more quickly, and future versions of gdb will use this hardware.
3968 watch EXP: Set a watchpoint (breakpoint) for an expression.
3970 info watchpoints: Information about your watchpoints.
3972 delete N: Deletes watchpoint number N (same as breakpoints).
3973 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3974 enable N: Re-enables watchpoint number N (same as breakpoints).
3977 * C++ multiple inheritance
3979 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3982 * C++ exception handling
3984 Gdb now supports limited C++ exception handling. Besides the existing
3985 ability to breakpoint on an exception handler, gdb can breakpoint on
3986 the raising of an exception (before the stack is peeled back to the
3989 catch FOO: If there is a FOO exception handler in the dynamic scope,
3990 set a breakpoint to catch exceptions which may be raised there.
3991 Multiple exceptions (``catch foo bar baz'') may be caught.
3993 info catch: Lists all exceptions which may be caught in the
3994 current stack frame.
3997 * Minor command changes
3999 The command ``call func (arg, arg, ...)'' now acts like the print
4000 command, except it does not print or save a value if the function's result
4001 is void. This is similar to dbx usage.
4003 The ``up'' and ``down'' commands now always print the frame they end up
4004 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4005 frames without printing.
4007 * New directory command
4009 'dir' now adds directories to the FRONT of the source search path.
4010 The path starts off empty. Source files that contain debug information
4011 about the directory in which they were compiled can be found even
4012 with an empty path; Sun CC and GCC include this information. If GDB can't
4013 find your source file in the current directory, type "dir .".
4015 * Configuring GDB for compilation
4017 For normal use, type ``./configure host''. See README or gdb.texinfo
4020 GDB now handles cross debugging. If you are remotely debugging between
4021 two different machines, type ``./configure host -target=targ''.
4022 Host is the machine where GDB will run; targ is the machine
4023 where the program that you are debugging will run.