1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.0
8 Xilinx MicroBlaze microblaze-*-*
13 Xilinx MicroBlaze microblaze
16 * Multi-program debugging.
18 GDB now has support for multi-program (a.k.a. multi-executable or
19 multi-exec) debugging. This allows for debugging multiple inferiors
20 simultaneously each running a different program under the same GDB
21 session. See "Debugging Multiple Inferiors and Programs" in the
22 manual for more information. This implied some user visible changes
23 in the multi-inferior support. For example, "info inferiors" now
24 lists inferiors that are not running yet or that have exited
25 already. See also "New commands" and "New options" below.
27 * New tracing features
29 GDB's tracepoint facility now includes several new features:
31 ** Trace state variables
33 GDB tracepoints now include support for trace state variables, which
34 are variables managed by the target agent during a tracing
35 experiment. They are useful for tracepoints that trigger each
36 other, so for instance one tracepoint can count hits in a variable,
37 and then a second tracepoint has a condition that is true when the
38 count reaches a particular value. Trace state variables share the
39 $-syntax of GDB convenience variables, and can appear in both
40 tracepoint actions and condition expressions. Use the "tvariable"
41 command to create, and "info tvariables" to view; see "Trace State
42 Variables" in the manual for more detail.
46 GDB now includes an option for defining fast tracepoints, which
47 targets may implement more efficiently, such as by installing a jump
48 into the target agent rather than a trap instruction. The resulting
49 speedup can be by two orders of magnitude or more, although the
50 tradeoff is that some program locations on some target architectures
51 might not allow fast tracepoint installation, for instance if the
52 instruction to be replaced is shorter than the jump. To request a
53 fast tracepoint, use the "ftrace" command, with syntax identical to
54 the regular trace command.
56 ** Disconnected tracing
58 It is now possible to detach GDB from the target while it is running
59 a trace experiment, then reconnect later to see how the experiment
60 is going. In addition, a new variable disconnected-tracing lets you
61 tell the target agent whether to continue running a trace if the
62 connection is lost unexpectedly.
66 GDB now has the ability to save the trace buffer into a file, and
67 then use that file as a target, similarly to you can do with
68 corefiles. You can select trace frames, print data that was
69 collected in them, and use tstatus to display the state of the
70 tracing run at the moment that it was saved. To create a trace
71 file, use "tsave <filename>", and to use it, do "target tfile
77 The disassemble command, when invoked with two arguments, now requires
78 the arguments to be comma-separated.
81 The info variables command now displays variable definitions. Files
82 which only declare a variable are not shown.
85 The source command is now capable of sourcing Python scripts.
86 This feature is dependent on the debugger being build with Python
89 Related to this enhancement is also the introduction of a new command
90 "set script-extension" (see below).
92 * New commands (for set/show, see "New options" below)
94 record save [<FILENAME>]
95 Save a file (in core file format) containing the process record
96 execution log for replay debugging at a later time.
98 record restore <FILENAME>
99 Restore the process record execution log that was saved at an
100 earlier time, for replay debugging.
102 add-inferior [-copies <N>] [-exec <FILENAME>]
105 clone-inferior [-copies <N>] [ID]
106 Make a new inferior ready to execute the same program another
112 maint info program-spaces
113 List the program spaces loaded into GDB.
115 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
116 show remote interrupt-sequence
117 Allow the user to select one of ^C, a BREAK signal or BREAK-g
118 as the sequence to the remote target in order to interrupt the execution.
119 Ctrl-C is a default. Some system prefers BREAK which is high level of
120 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
121 Magic SysRq g. It is BREAK signal and character 'g'.
123 set remote interrupt-on-connect [on | off]
124 show remote interrupt-on-connect
125 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
126 remote target when gdb connects to it. This is needed when you debug
129 set remotebreak [on | off]
131 Deprecated. Use "set/show remote interrupt-sequence" instead.
133 tvariable $NAME [ = EXP ]
134 Create or modify a trace state variable.
137 List trace state variables and their values.
139 delete tvariable $NAME ...
140 Delete one or more trace state variables.
143 Evaluate the given expressions without collecting anything into the
144 trace buffer. (Valid in tracepoint actions only.)
146 ftrace FN / FILE:LINE / *ADDR
147 Define a fast tracepoint at the given function, line, or address.
149 * New expression syntax
151 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
152 GDB now parses 0b101010 identically with 42.
156 set follow-exec-mode new|same
157 show follow-exec-mode
158 Control whether GDB reuses the same inferior across an exec call or
159 creates a new one. This is useful to be able to restart the old
160 executable after the inferior having done an exec call.
162 set default-collect EXPR, ...
164 Define a list of expressions to be collected at each tracepoint.
165 This is a useful way to ensure essential items are not overlooked,
166 such as registers or a critical global variable.
168 set disconnected-tracing
169 show disconnected-tracing
170 If set to 1, the target is instructed to continue tracing if it
171 loses its connection to GDB. If 0, the target is to stop tracing
174 set script-extension off|soft|strict
175 show script-extension
176 If set to "off", the debugger does not perform any script language
177 recognition, and all sourced files are assumed to be GDB scripts.
178 If set to "soft" (the default), files are sourced according to
179 filename extension, falling back to GDB scripts if the first
181 If set to "strict", files are sourced according to filename extension.
183 set ada trust-PAD-over-XVS on|off
184 show ada trust-PAD-over-XVS
185 If off, activate a workaround against a bug in the debugging information
186 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
187 the GCC sources for more information about the GNAT encoding and
188 PAD types in particular). It is always safe to set this option to
189 off, but this introduces a slight performance penalty. The default
195 Define a trace state variable.
198 Get the current value of a trace state variable.
201 Set desired tracing behavior upon disconnection.
204 Get data about the tracepoints currently in use.
208 Process record now works correctly with hardware watchpoints.
210 Multiple bug fixes have been made to the mips-irix port, making it
211 much more reliable. In particular:
212 - Debugging threaded applications is now possible again. Previously,
213 GDB would hang while starting the program, or while waiting for
214 the program to stop at a breakpoint.
215 - Attaching to a running process no longer hangs.
216 - An error occurring while loading a core file has been fixed.
217 - Changing the value of the PC register now works again. This fixes
218 problems observed when using the "jump" command, or when calling
219 a function from GDB, or even when assigning a new value to $pc.
220 - With the "finish" and "return" commands, the return value for functions
221 returning a small array is now correctly printed.
222 - It is now possible to break on shared library code which gets executed
223 during a shared library init phase (code executed while executing
224 their .init section). Previously, the breakpoint would have no effect.
225 - GDB is now able to backtrace through the signal handler for
226 non-threaded programs.
228 PIE (Position Independent Executable) programs debugging is now supported.
229 This includes debugging execution of PIC (Position Independent Code) shared
230 libraries although for that, it should be possible to run such libraries as an
233 *** Changes in GDB 7.0
235 * GDB now has an interface for JIT compilation. Applications that
236 dynamically generate code can create symbol files in memory and register
237 them with GDB. For users, the feature should work transparently, and
238 for JIT developers, the interface is documented in the GDB manual in the
239 "JIT Compilation Interface" chapter.
241 * Tracepoints may now be conditional. The syntax is as for
242 breakpoints; either an "if" clause appended to the "trace" command,
243 or the "condition" command is available. GDB sends the condition to
244 the target for evaluation using the same bytecode format as is used
245 for tracepoint actions.
247 * "disassemble" command with a /r modifier, print the raw instructions
248 in hex as well as in symbolic form."
250 * Process record and replay
252 In a architecture environment that supports ``process record and
253 replay'', ``process record and replay'' target can record a log of
254 the process execution, and replay it with both forward and reverse
257 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
258 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
259 set execution-direction {forward|reverse}, for targets that support
262 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
263 feature is available with a native GDB running on kernel version
266 * GDB now has support for multi-byte and wide character sets on the
267 target. Strings whose character type is wchar_t, char16_t, or
268 char32_t are now correctly printed. GDB supports wide- and unicode-
269 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
270 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
271 `printf'. This feature requires iconv to work properly; if your
272 system does not have a working iconv, GDB can use GNU libiconv. See
273 the installation instructions for more information.
275 * GDB now supports automatic retrieval of shared library files from
276 remote targets. To use this feature, specify a system root that begins
277 with the `remote:' prefix, either via the `set sysroot' command or via
278 the `--with-sysroot' configure-time option.
280 * "info sharedlibrary" now takes an optional regex of libraries to show,
281 and it now reports if a shared library has no debugging information.
283 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
284 now complete on file names.
286 * When completing in expressions, gdb will attempt to limit
287 completions to allowable structure or union fields, where appropriate.
288 For instance, consider:
290 # struct example { int f1; double f2; };
291 # struct example variable;
294 If the user types TAB at the end of this command line, the available
295 completions will be "f1" and "f2".
297 * Inlined functions are now supported. They show up in backtraces, and
298 the "step", "next", and "finish" commands handle them automatically.
300 * GDB now supports the token-splicing (##) and stringification (#)
301 operators when expanding macros. It also supports variable-arity
304 * GDB now supports inspecting extra signal information, exported by
305 the new $_siginfo convenience variable. The feature is currently
306 implemented on linux ARM, i386 and amd64.
308 * GDB can now display the VFP floating point registers and NEON vector
309 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
310 can provide these registers (requires Linux 2.6.30 or later). Remote
311 and simulator targets may also provide them.
316 Search memory for a sequence of bytes.
319 Turn off `+'/`-' protocol acknowledgments to permit more efficient
320 operation over reliable transport links. Use of this packet is
321 controlled by the `set remote noack-packet' command.
324 Kill the process with the specified process ID. Use this in preference
325 to `k' when multiprocess protocol extensions are supported.
328 Obtains additional operating system information
332 Read or write additional signal information.
334 * Removed remote protocol undocumented extension
336 An undocumented extension to the remote protocol's `S' stop reply
337 packet that permited the stub to pass a process id was removed.
338 Remote servers should use the `T' stop reply packet instead.
340 * The "disassemble" command now supports an optional /m modifier to print mixed
343 * GDB now supports multiple function calling conventions according to the
344 DWARF-2 DW_AT_calling_convention function attribute.
346 * The SH target utilizes the aforementioned change to distinguish between gcc
347 and Renesas calling convention. It also adds the new CLI commands
348 `set/show sh calling-convention'.
350 * GDB can now read compressed debug sections, as produced by GNU gold
351 with the --compress-debug-sections=zlib flag.
353 * 64-bit core files are now supported on AIX.
355 * Thread switching is now supported on Tru64.
357 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
358 which will be allocated using malloc later in program execution.
360 * The qXfer:libraries:read remote procotol packet now allows passing a
361 list of section offsets.
363 * On GNU/Linux, GDB can now attach to stopped processes. Several race
364 conditions handling signals delivered during attach or thread creation
365 have also been fixed.
367 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
368 From the user's standpoint, all unqualified instances of True and False
369 are treated as the standard definitions, regardless of context.
371 * GDB now parses C++ symbol and type names more flexibly. For
374 template<typename T> class C { };
377 GDB will now correctly handle all of:
379 ptype C<char const *>
381 ptype C<const char *>
384 * New features in the GDB remote stub, gdbserver
386 - The "--wrapper" command-line argument tells gdbserver to use a
387 wrapper program to launch programs for debugging.
389 - On PowerPC and S/390 targets, it is now possible to use a single
390 gdbserver executable to debug both 32-bit and 64-bit programs.
391 (This requires gdbserver itself to be built as a 64-bit executable.)
393 - gdbserver uses the new noack protocol mode for TCP connections to
394 reduce communications latency, if also supported and enabled in GDB.
396 - Support for the sparc64-linux-gnu target is now included in
399 - The amd64-linux build of gdbserver now supports debugging both
400 32-bit and 64-bit programs.
402 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
403 now support hardware watchpoints, and will use them automatically
408 GDB now has support for scripting using Python. Whether this is
409 available is determined at configure time.
411 New GDB commands can now be written in Python.
413 * Ada tasking support
415 Ada tasks can now be inspected in GDB. The following commands have
419 Print the list of Ada tasks.
421 Print detailed information about task number N.
423 Print the task number of the current task.
425 Switch the context of debugging to task number N.
427 * Support for user-defined prefixed commands. The "define" command can
428 add new commands to existing prefixes, e.g. "target".
430 * Multi-inferior, multi-process debugging.
432 GDB now has generalized support for multi-inferior debugging. See
433 "Debugging Multiple Inferiors" in the manual for more information.
434 Although availability still depends on target support, the command
435 set is more uniform now. The GNU/Linux specific multi-forks support
436 has been migrated to this new framework. This implied some user
437 visible changes; see "New commands" and also "Removed commands"
440 * Target descriptions can now describe the target OS ABI. See the
441 "Target Description Format" section in the user manual for more
444 * Target descriptions can now describe "compatible" architectures
445 to indicate that the target can execute applications for a different
446 architecture in addition to those for the main target architecture.
447 See the "Target Description Format" section in the user manual for
450 * Multi-architecture debugging.
452 GDB now includes general supports for debugging applications on
453 hybrid systems that use more than one single processor architecture
454 at the same time. Each such hybrid architecture still requires
455 specific support to be added. The only hybrid architecture supported
456 in this version of GDB is the Cell Broadband Engine.
458 * GDB now supports integrated debugging of Cell/B.E. applications that
459 use both the PPU and SPU architectures. To enable support for hybrid
460 Cell/B.E. debugging, you need to configure GDB to support both the
461 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
462 --enable-targets configure option.
464 * Non-stop mode debugging.
466 For some targets, GDB now supports an optional mode of operation in
467 which you can examine stopped threads while other threads continue
468 to execute freely. This is referred to as non-stop mode, with the
469 old mode referred to as all-stop mode. See the "Non-Stop Mode"
470 section in the user manual for more information.
472 To be able to support remote non-stop debugging, a remote stub needs
473 to implement the non-stop mode remote protocol extensions, as
474 described in the "Remote Non-Stop" section of the user manual. The
475 GDB remote stub, gdbserver, has been adjusted to support these
476 extensions on linux targets.
478 * New commands (for set/show, see "New options" below)
480 catch syscall [NAME(S) | NUMBER(S)]
481 Catch system calls. Arguments, which should be names of system
482 calls or their numbers, mean catch only those syscalls. Without
483 arguments, every syscall will be caught. When the inferior issues
484 any of the specified syscalls, GDB will stop and announce the system
485 call, both when it is called and when its call returns. This
486 feature is currently available with a native GDB running on the
487 Linux Kernel, under the following architectures: x86, x86_64,
488 PowerPC and PowerPC64.
490 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
492 Search memory for a sequence of bytes.
494 maint set python print-stack
495 maint show python print-stack
496 Show a stack trace when an error is encountered in a Python script.
499 Invoke CODE by passing it to the Python interpreter.
504 These allow macros to be defined, undefined, and listed
508 Show operating system information about processes.
511 List the inferiors currently under GDB's control.
514 Switch focus to inferior number NUM.
517 Detach from inferior number NUM.
520 Kill inferior number NUM.
525 show spu stop-on-load
526 Control whether to stop for new SPE threads during Cell/B.E. debugging.
528 set spu auto-flush-cache
529 show spu auto-flush-cache
530 Control whether to automatically flush the software-managed cache
531 during Cell/B.E. debugging.
533 set sh calling-convention
534 show sh calling-convention
535 Control the calling convention used when calling SH target functions.
539 Control display of timestamps with GDB debugging output.
541 set disassemble-next-line
542 show disassemble-next-line
543 Control display of disassembled source lines or instructions when
546 set remote noack-packet
547 show remote noack-packet
548 Set/show the use of remote protocol QStartNoAckMode packet. See above
549 under "New remote packets."
551 set remote query-attached-packet
552 show remote query-attached-packet
553 Control use of remote protocol `qAttached' (query-attached) packet.
555 set remote read-siginfo-object
556 show remote read-siginfo-object
557 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
560 set remote write-siginfo-object
561 show remote write-siginfo-object
562 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
565 set remote reverse-continue
566 show remote reverse-continue
567 Control use of remote protocol 'bc' (reverse-continue) packet.
569 set remote reverse-step
570 show remote reverse-step
571 Control use of remote protocol 'bs' (reverse-step) packet.
573 set displaced-stepping
574 show displaced-stepping
575 Control displaced stepping mode. Displaced stepping is a way to
576 single-step over breakpoints without removing them from the debuggee.
577 Also known as "out-of-line single-stepping".
581 Control display of debugging info for displaced stepping.
583 maint set internal-error
584 maint show internal-error
585 Control what GDB does when an internal error is detected.
587 maint set internal-warning
588 maint show internal-warning
589 Control what GDB does when an internal warning is detected.
594 Use a wrapper program to launch programs for debugging.
596 set multiple-symbols (all|ask|cancel)
597 show multiple-symbols
598 The value of this variable can be changed to adjust the debugger behavior
599 when an expression or a breakpoint location contains an ambiguous symbol
600 name (an overloaded function name, for instance).
602 set breakpoint always-inserted
603 show breakpoint always-inserted
604 Keep breakpoints always inserted in the target, as opposed to inserting
605 them when resuming the target, and removing them when the target stops.
606 This option can improve debugger performance on slow remote targets.
608 set arm fallback-mode (arm|thumb|auto)
609 show arm fallback-mode
610 set arm force-mode (arm|thumb|auto)
612 These commands control how ARM GDB determines whether instructions
613 are ARM or Thumb. The default for both settings is auto, which uses
614 the current CPSR value for instructions without symbols; previous
615 versions of GDB behaved as if "set arm fallback-mode arm".
617 set disable-randomization
618 show disable-randomization
619 Standalone programs run with the virtual address space randomization enabled
620 by default on some platforms. This option keeps the addresses stable across
621 multiple debugging sessions.
625 Control whether other threads are stopped or not when some thread hits
630 Requests that asynchronous execution is enabled in the target, if available.
631 In this case, it's possible to resume target in the background, and interact
632 with GDB while the target is running. "show target-async" displays the
633 current state of asynchronous execution of the target.
635 set target-wide-charset
636 show target-wide-charset
637 The target-wide-charset is the name of the character set that GDB
638 uses when printing characters whose type is wchar_t.
640 set tcp auto-retry (on|off)
642 set tcp connect-timeout
643 show tcp connect-timeout
644 These commands allow GDB to retry failed TCP connections to a remote stub
645 with a specified timeout period; this is useful if the stub is launched
646 in parallel with GDB but may not be ready to accept connections immediately.
648 set libthread-db-search-path
649 show libthread-db-search-path
650 Control list of directories which GDB will search for appropriate
653 set schedule-multiple (on|off)
654 show schedule-multiple
655 Allow GDB to resume all threads of all processes or only threads of
660 Use more aggressive caching for accesses to the stack. This improves
661 performance of remote debugging (particularly backtraces) without
662 affecting correctness.
664 set interactive-mode (on|off|auto)
665 show interactive-mode
666 Control whether GDB runs in interactive mode (on) or not (off).
667 When in interactive mode, GDB waits for the user to answer all
668 queries. Otherwise, GDB does not wait and assumes the default
669 answer. When set to auto (the default), GDB determines which
670 mode to use based on the stdin settings.
675 For program forks, this is replaced by the new more generic `info
676 inferiors' command. To list checkpoints, you can still use the
677 `info checkpoints' command, which was an alias for the `info forks'
681 Replaced by the new `inferior' command. To switch between
682 checkpoints, you can still use the `restart' command, which was an
683 alias for the `fork' command.
686 This is removed, since some targets don't have a notion of
687 processes. To switch between processes, you can still use the
688 `inferior' command using GDB's own inferior number.
691 For program forks, this is replaced by the new more generic `kill
692 inferior' command. To delete a checkpoint, you can still use the
693 `delete checkpoint' command, which was an alias for the `delete
697 For program forks, this is replaced by the new more generic `detach
698 inferior' command. To detach a checkpoint, you can still use the
699 `detach checkpoint' command, which was an alias for the `detach
702 * New native configurations
704 x86/x86_64 Darwin i[34567]86-*-darwin*
706 x86_64 MinGW x86_64-*-mingw*
710 Lattice Mico32 lm32-*
711 x86 DICOS i[34567]86-*-dicos*
712 x86_64 DICOS x86_64-*-dicos*
715 * The GDB remote stub, gdbserver, now supports x86 Windows CE
716 (mingw32ce) debugging.
722 These commands were actually not implemented on any target.
724 *** Changes in GDB 6.8
726 * New native configurations
728 NetBSD/hppa hppa*-*netbsd*
729 Xtensa GNU/Linux xtensa*-*-linux*
733 NetBSD/hppa hppa*-*-netbsd*
734 Xtensa GNU/Lunux xtensa*-*-linux*
736 * Change in command line behavior -- corefiles vs. process ids.
738 When the '-p NUMBER' or '--pid NUMBER' options are used, and
739 attaching to process NUMBER fails, GDB no longer attempts to open a
740 core file named NUMBER. Attaching to a program using the -c option
741 is no longer supported. Instead, use the '-p' or '--pid' options.
743 * GDB can now be built as a native debugger for debugging Windows x86
744 (mingw32) Portable Executable (PE) programs.
746 * Pending breakpoints no longer change their number when their address
749 * GDB now supports breakpoints with multiple locations,
750 including breakpoints on C++ constructors, inside C++ templates,
751 and in inlined functions.
753 * GDB's ability to debug optimized code has been improved. GDB more
754 accurately identifies function bodies and lexical blocks that occupy
755 more than one contiguous range of addresses.
757 * Target descriptions can now describe registers for PowerPC.
759 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
760 registers on PowerPC targets.
762 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
763 targets even when the libthread_db library is not available.
765 * The GDB remote stub, gdbserver, now supports the new file transfer
766 commands (remote put, remote get, and remote delete).
768 * The GDB remote stub, gdbserver, now supports run and attach in
769 extended-remote mode.
771 * hppa*64*-*-hpux11* target broken
772 The debugger is unable to start a program and fails with the following
773 error: "Error trying to get information about dynamic linker".
774 The gdb-6.7 release is also affected.
776 * GDB now supports the --enable-targets= configure option to allow
777 building a single GDB executable that supports multiple remote
778 target architectures.
780 * GDB now supports debugging C and C++ programs which use the
781 Decimal Floating Point extension. In addition, the PowerPC target
782 now has a set of pseudo-registers to inspect decimal float values
783 stored in two consecutive float registers.
785 * The -break-insert MI command can optionally create pending
788 * Improved support for debugging Ada
789 Many improvements to the Ada language support have been made. These
791 - Better support for Ada2005 interface types
792 - Improved handling of arrays and slices in general
793 - Better support for Taft-amendment types
794 - The '{type} ADDRESS' expression is now allowed on the left hand-side
796 - Improved command completion in Ada
799 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
804 set print frame-arguments (all|scalars|none)
805 show print frame-arguments
806 The value of this variable can be changed to control which argument
807 values should be printed by the debugger when displaying a frame.
812 Transfer files to and from a remote target, and delete remote files.
819 Transfer files to and from a remote target, and delete remote files.
828 Open, close, read, write, and delete files on the remote system.
831 Attach to an existing process on the remote system, in extended-remote
835 Run a new process on the remote system, in extended-remote mode.
837 *** Changes in GDB 6.7
839 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
840 bfd, libiberty and opcodes, as revealed by static analysis donated by
841 Coverity, Inc. (http://scan.coverity.com).
843 * When looking up multiply-defined global symbols, GDB will now prefer the
844 symbol definition in the current shared library if it was built using the
845 -Bsymbolic linker option.
847 * When the Text User Interface (TUI) is not configured, GDB will now
848 recognize the -tui command-line option and print a message that the TUI
851 * The GDB remote stub, gdbserver, now has lower overhead for high
852 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
854 * GDB for MIPS targets now autodetects whether a remote target provides
855 32-bit or 64-bit register values.
857 * Support for C++ member pointers has been improved.
859 * GDB now understands XML target descriptions, which specify the
860 target's overall architecture. GDB can read a description from
861 a local file or over the remote serial protocol.
863 * Vectors of single-byte data use a new integer type which is not
864 automatically displayed as character or string data.
866 * The /s format now works with the print command. It displays
867 arrays of single-byte integers and pointers to single-byte integers
870 * Target descriptions can now describe target-specific registers,
871 for architectures which have implemented the support (currently
872 only ARM, M68K, and MIPS).
874 * GDB and the GDB remote stub, gdbserver, now support the XScale
877 * The GDB remote stub, gdbserver, has been updated to support
878 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
879 has been rewritten to use the standard GDB remote protocol.
881 * GDB can now step into C++ functions which are called through thunks.
883 * GDB for the Cell/B.E. SPU now supports overlay debugging.
885 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
886 layout. It also supports a TextSeg= and DataSeg= response when only
887 segment base addresses (rather than offsets) are available.
889 * The /i format now outputs any trailing branch delay slot instructions
890 immediately following the last instruction within the count specified.
892 * The GDB remote protocol "T" stop reply packet now supports a
893 "library" response. Combined with the new "qXfer:libraries:read"
894 packet, this response allows GDB to debug shared libraries on targets
895 where the operating system manages the list of loaded libraries (e.g.
896 Windows and SymbianOS).
898 * The GDB remote stub, gdbserver, now supports dynamic link libraries
899 (DLLs) on Windows and Windows CE targets.
901 * GDB now supports a faster verification that a .debug file matches its binary
902 according to its build-id signature, if the signature is present.
908 Enable or disable hardware flow control (RTS/CTS) on the serial port
909 when debugging using remote targets.
911 set mem inaccessible-by-default
912 show mem inaccessible-by-default
913 If the target supplies a memory map, for instance via the remote
914 protocol's "qXfer:memory-map:read" packet, setting this variable
915 prevents GDB from accessing memory outside the memory map. This
916 is useful for targets with memory mapped registers or which react
917 badly to accesses of unmapped address space.
919 set breakpoint auto-hw
920 show breakpoint auto-hw
921 If the target supplies a memory map, for instance via the remote
922 protocol's "qXfer:memory-map:read" packet, setting this variable
923 lets GDB use hardware breakpoints automatically for memory regions
924 where it can not use software breakpoints. This covers both the
925 "break" command and internal breakpoints used for other commands
926 including "next" and "finish".
929 catch exception unhandled
930 Stop the program execution when Ada exceptions are raised.
933 Stop the program execution when an Ada assertion failed.
937 Set an alternate system root for target files. This is a more
938 general version of "set solib-absolute-prefix", which is now
939 an alias to "set sysroot".
942 Provide extended SPU facility status information. This set of
943 commands is available only when debugging the Cell/B.E. SPU
946 * New native configurations
948 OpenBSD/sh sh*-*openbsd*
953 Use the specified local file as an XML target description, and do
954 not query the target for its built-in description.
958 OpenBSD/sh sh*-*-openbsd*
959 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
960 Toshiba Media Processor mep-elf
965 Ignore the specified signals; pass them directly to the debugged program
966 without stopping other threads or reporting them to GDB.
969 Read an XML target description from the target, which describes its
974 Read or write contents of an spufs file on the target system. These
975 packets are available only on the Cell/B.E. SPU architecture.
977 qXfer:libraries:read:
978 Report the loaded shared libraries. Combined with new "T" packet
979 response, this packet allows GDB to debug shared libraries on
980 targets where the operating system manages the list of loaded
981 libraries (e.g. Windows and SymbianOS).
985 Support for these obsolete configurations has been removed.
994 i[34567]86-*-netware*
995 i[34567]86-*-sco3.2v5*
996 i[34567]86-*-sco3.2v4*
998 i[34567]86-*-sysv4.2*
1001 i[34567]86-*-unixware2*
1002 i[34567]86-*-unixware*
1011 * Other removed features
1018 Various m68k-only ROM monitors.
1025 Various Renesas ROM monitors and debugging interfaces for SH and
1030 Support for a Macraigor serial interface to on-chip debugging.
1031 GDB does not directly support the newer parallel or USB
1036 A debug information format. The predecessor to DWARF 2 and
1037 DWARF 3, which are still supported.
1039 Support for the HP aCC compiler on HP-UX/PA-RISC
1041 SOM-encapsulated symbolic debugging information, automatic
1042 invocation of pxdb, and the aCC custom C++ ABI. This does not
1043 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1044 with aCC can still be debugged on an assembly level.
1046 MIPS ".pdr" sections
1048 A MIPS-specific format used to describe stack frame layout
1049 in debugging information.
1053 GDB could work with an older version of Guile to debug
1054 the interpreter and Scheme programs running in it.
1056 set mips stack-arg-size
1057 set mips saved-gpreg-size
1059 Use "set mips abi" to control parameter passing for MIPS.
1061 *** Changes in GDB 6.6
1066 Cell Broadband Engine SPU spu-elf
1068 * GDB can now be configured as a cross-debugger targeting native Windows
1069 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1070 running on a Windows system over TCP/IP to debug Windows programs.
1072 * The GDB remote stub, gdbserver, has been updated to support Windows and
1073 Cygwin debugging. Both single-threaded and multi-threaded programs are
1076 * The "set trust-readonly-sections" command works again. This command was
1077 broken in GDB 6.3, 6.4, and 6.5.
1079 * The "load" command now supports writing to flash memory, if the remote
1080 stub provides the required support.
1082 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1083 longer requires symbolic debug information (e.g. DWARF-2).
1088 unset substitute-path
1089 show substitute-path
1090 Manage a list of substitution rules that GDB uses to rewrite the name
1091 of the directories where the sources are located. This can be useful
1092 for instance when the sources were moved to a different location
1093 between compilation and debugging.
1097 Print each CLI command as it is executed. Each command is prefixed with
1098 a number of `+' symbols representing the nesting depth.
1099 The source command now has a `-v' option to enable the same feature.
1103 The ARM Demon monitor support (RDP protocol, "target rdp").
1105 Kernel Object Display, an embedded debugging feature which only worked with
1106 an obsolete version of Cisco IOS.
1108 The 'set download-write-size' and 'show download-write-size' commands.
1110 * New remote packets
1113 Tell a stub about GDB client features, and request remote target features.
1114 The first feature implemented is PacketSize, which allows the target to
1115 specify the size of packets it can handle - to minimize the number of
1116 packets required and improve performance when connected to a remote
1120 Fetch an OS auxilliary vector from the remote stub. This packet is a
1121 more efficient replacement for qPart:auxv:read.
1123 qXfer:memory-map:read:
1124 Fetch a memory map from the remote stub, including information about
1125 RAM, ROM, and flash memory devices.
1130 Erase and program a flash memory device.
1132 * Removed remote packets
1135 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1136 used it, and only gdbserver implemented it.
1138 *** Changes in GDB 6.5
1142 Renesas M32C/M16C m32c-elf
1144 Morpho Technologies ms1 ms1-elf
1148 init-if-undefined Initialize a convenience variable, but
1149 only if it doesn't already have a value.
1151 The following commands are presently only implemented for native GNU/Linux:
1153 checkpoint Save a snapshot of the program state.
1155 restart <n> Return the program state to a
1156 previously saved state.
1158 info checkpoints List currently saved checkpoints.
1160 delete-checkpoint <n> Delete a previously saved checkpoint.
1162 set|show detach-on-fork Tell gdb whether to detach from a newly
1163 forked process, or to keep debugging it.
1165 info forks List forks of the user program that
1166 are available to be debugged.
1168 fork <n> Switch to debugging one of several
1169 forks of the user program that are
1170 available to be debugged.
1172 delete-fork <n> Delete a fork from the list of forks
1173 that are available to be debugged (and
1174 kill the forked process).
1176 detach-fork <n> Delete a fork from the list of forks
1177 that are available to be debugged (and
1178 allow the process to continue).
1182 Morpho Technologies ms2 ms1-elf
1184 * Improved Windows host support
1186 GDB now builds as a cross debugger hosted on i686-mingw32, including
1187 native console support, and remote communications using either
1188 network sockets or serial ports.
1190 * Improved Modula-2 language support
1192 GDB can now print most types in the Modula-2 syntax. This includes:
1193 basic types, set types, record types, enumerated types, range types,
1194 pointer types and ARRAY types. Procedure var parameters are correctly
1195 printed and hexadecimal addresses and character constants are also
1196 written in the Modula-2 syntax. Best results can be obtained by using
1197 GNU Modula-2 together with the -gdwarf-2 command line option.
1201 The ARM rdi-share module.
1203 The Netware NLM debug server.
1205 *** Changes in GDB 6.4
1207 * New native configurations
1209 OpenBSD/arm arm*-*-openbsd*
1210 OpenBSD/mips64 mips64-*-openbsd*
1214 Morpho Technologies ms1 ms1-elf
1216 * New command line options
1218 --batch-silent As for --batch, but totally silent.
1219 --return-child-result The debugger will exist with the same value
1220 the child (debugged) program exited with.
1221 --eval-command COMMAND, -ex COMMAND
1222 Execute a single GDB CLI command. This may be
1223 specified multiple times and in conjunction
1224 with the --command (-x) option.
1226 * Deprecated commands removed
1228 The following commands, that were deprecated in 2000, have been
1232 set|show arm disassembly-flavor set|show arm disassembler
1233 othernames set arm disassembler
1234 set|show remotedebug set|show debug remote
1235 set|show archdebug set|show debug arch
1236 set|show eventdebug set|show debug event
1239 * New BSD user-level threads support
1241 It is now possible to debug programs using the user-level threads
1242 library on OpenBSD and FreeBSD. Currently supported (target)
1245 FreeBSD/amd64 x86_64-*-freebsd*
1246 FreeBSD/i386 i386-*-freebsd*
1247 OpenBSD/i386 i386-*-openbsd*
1249 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1250 are not yet supported.
1252 * New support for Matsushita MN10300 w/sim added
1253 (Work in progress). mn10300-elf.
1255 * REMOVED configurations and files
1257 VxWorks and the XDR protocol *-*-vxworks
1258 Motorola MCORE mcore-*-*
1259 National Semiconductor NS32000 ns32k-*-*
1261 * New "set print array-indexes" command
1263 After turning this setting "on", GDB prints the index of each element
1264 when displaying arrays. The default is "off" to preserve the previous
1267 * VAX floating point support
1269 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1271 * User-defined command support
1273 In addition to using $arg0..$arg9 for argument passing, it is now possible
1274 to use $argc to determine now many arguments have been passed. See the
1275 section on user-defined commands in the user manual for more information.
1277 *** Changes in GDB 6.3:
1279 * New command line option
1281 GDB now accepts -l followed by a number to set the timeout for remote
1284 * GDB works with GCC -feliminate-dwarf2-dups
1286 GDB now supports a more compact representation of DWARF-2 debug
1287 information using DW_FORM_ref_addr references. These are produced
1288 by GCC with the option -feliminate-dwarf2-dups and also by some
1289 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1290 to use -feliminate-dwarf2-dups.
1292 * Internationalization
1294 When supported by the host system, GDB will be built with
1295 internationalization (libintl). The task of marking up the sources is
1296 continued, we're looking forward to our first translation.
1300 Initial support for debugging programs compiled with the GNAT
1301 implementation of the Ada programming language has been integrated
1302 into GDB. In this release, support is limited to expression evaluation.
1304 * New native configurations
1306 GNU/Linux/m32r m32r-*-linux-gnu
1310 GDB's remote protocol now includes support for the 'p' packet. This
1311 packet is used to fetch individual registers from a remote inferior.
1313 * END-OF-LIFE registers[] compatibility module
1315 GDB's internal register infrastructure has been completely rewritten.
1316 The new infrastructure making possible the implementation of key new
1317 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1320 GDB 6.3 will be the last release to include the the registers[]
1321 compatibility module that allowed out-of-date configurations to
1322 continue to work. This change directly impacts the following
1332 powerpc bdm protocol
1334 Unless there is activity to revive these configurations, they will be
1335 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1337 * OBSOLETE configurations and files
1339 Configurations that have been declared obsolete in this release have
1340 been commented out. Unless there is activity to revive these
1341 configurations, the next release of GDB will have their sources
1342 permanently REMOVED.
1351 *** Changes in GDB 6.2.1:
1353 * MIPS `break main; run' gave an heuristic-fence-post warning
1355 When attempting to run even a simple program, a warning about
1356 heuristic-fence-post being hit would be reported. This problem has
1359 * MIPS IRIX 'long double' crashed GDB
1361 When examining a long double variable, GDB would get a segmentation
1362 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1363 IRIX long double values).
1367 A bug in the VAX stack code was causing problems with the "next"
1368 command. This problem has been fixed.
1370 *** Changes in GDB 6.2:
1372 * Fix for ``many threads''
1374 On GNU/Linux systems that use the NPTL threads library, a program
1375 rapidly creating and deleting threads would confuse GDB leading to the
1378 ptrace: No such process.
1379 thread_db_get_info: cannot get thread info: generic error
1381 This problem has been fixed.
1383 * "-async" and "-noasync" options removed.
1385 Support for the broken "-noasync" option has been removed (it caused
1388 * New ``start'' command.
1390 This command runs the program until the begining of the main procedure.
1392 * New BSD Kernel Data Access Library (libkvm) interface
1394 Using ``target kvm'' it is now possible to debug kernel core dumps and
1395 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1396 platforms. Currently supported (native-only) configurations are:
1398 FreeBSD/amd64 x86_64-*-freebsd*
1399 FreeBSD/i386 i?86-*-freebsd*
1400 NetBSD/i386 i?86-*-netbsd*
1401 NetBSD/m68k m68*-*-netbsd*
1402 NetBSD/sparc sparc-*-netbsd*
1403 OpenBSD/amd64 x86_64-*-openbsd*
1404 OpenBSD/i386 i?86-*-openbsd*
1405 OpenBSD/m68k m68*-openbsd*
1406 OpenBSD/sparc sparc-*-openbsd*
1408 * Signal trampoline code overhauled
1410 Many generic problems with GDB's signal handling code have been fixed.
1411 These include: backtraces through non-contiguous stacks; recognition
1412 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1413 call; backtrace through a signal trampoline; step into and out of
1414 signal handlers; and single-stepping in the signal trampoline.
1416 Please note that kernel bugs are a limiting factor here. These
1417 features have been shown to work on an s390 GNU/Linux system that
1418 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1420 * Cygwin support for DWARF 2 added.
1422 * New native configurations
1424 GNU/Linux/hppa hppa*-*-linux*
1425 OpenBSD/hppa hppa*-*-openbsd*
1426 OpenBSD/m68k m68*-*-openbsd*
1427 OpenBSD/m88k m88*-*-openbsd*
1428 OpenBSD/powerpc powerpc-*-openbsd*
1429 NetBSD/vax vax-*-netbsd*
1430 OpenBSD/vax vax-*-openbsd*
1432 * END-OF-LIFE frame compatibility module
1434 GDB's internal frame infrastructure has been completely rewritten.
1435 The new infrastructure making it possible to support key new features
1436 including DWARF 2 Call Frame Information. To aid in the task of
1437 migrating old configurations to this new infrastructure, a
1438 compatibility module, that allowed old configurations to continue to
1439 work, was also included.
1441 GDB 6.2 will be the last release to include this frame compatibility
1442 module. This change directly impacts the following configurations:
1452 Unless there is activity to revive these configurations, they will be
1453 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1455 * REMOVED configurations and files
1457 Sun 3, running SunOS 3 m68*-*-sunos3*
1458 Sun 3, running SunOS 4 m68*-*-sunos4*
1459 Sun 2, running SunOS 3 m68000-*-sunos3*
1460 Sun 2, running SunOS 4 m68000-*-sunos4*
1461 Motorola 680x0 running LynxOS m68*-*-lynxos*
1462 AT&T 3b1/Unix pc m68*-att-*
1463 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1464 decstation mips-dec-* mips-little-*
1465 riscos mips-*-riscos* mips-*-sysv*
1466 sonymips mips-sony-*
1467 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1469 *** Changes in GDB 6.1.1:
1471 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1473 The TUI (Text-mode User Interface) is now built as part of a default
1474 GDB configuration. It is enabled by either selecting the TUI with the
1475 command line option "-i=tui" or by running the separate "gdbtui"
1476 program. For more information on the TUI, see the manual "Debugging
1479 * Pending breakpoint support (also included in GDB 6.1)
1481 Support has been added to allow you to specify breakpoints in shared
1482 libraries that have not yet been loaded. If a breakpoint location
1483 cannot be found, and the "breakpoint pending" option is set to auto,
1484 GDB queries you if you wish to make the breakpoint pending on a future
1485 shared-library load. If and when GDB resolves the breakpoint symbol,
1486 the pending breakpoint is removed as one or more regular breakpoints
1489 Pending breakpoints are very useful for GCJ Java debugging.
1491 * Fixed ISO-C build problems
1493 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1494 non ISO-C code that stopped them being built using a more strict ISO-C
1495 compiler (e.g., IBM's C compiler).
1497 * Fixed build problem on IRIX 5
1499 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1500 wasn't able to compile compile on an IRIX 5 system.
1502 * Added execute permission to gdb/gdbserver/configure
1504 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1505 permission. This bug would cause configure to fail on a number of
1506 systems (Solaris, IRIX). Ref: server/519.
1508 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1510 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1511 has been updated to use constant array sizes.
1513 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1515 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1516 its generated DWARF Call Frame Info. This encoding was causing GDB to
1517 panic, that panic has been fixed. Ref: gdb/1628.
1519 * Fixed a problem when examining parameters in shared library code.
1521 When examining parameters in optimized shared library code generated
1522 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1523 not available''. GDB now correctly displays the variable's value.
1525 *** Changes in GDB 6.1:
1527 * Removed --with-mmalloc
1529 Support for the mmalloc memory manager has been removed, as it
1530 conflicted with the internal gdb byte cache.
1532 * Changes in AMD64 configurations
1534 The AMD64 target now includes the %cs and %ss registers. As a result
1535 the AMD64 remote protocol has changed; this affects the floating-point
1536 and SSE registers. If you rely on those registers for your debugging,
1537 you should upgrade gdbserver on the remote side.
1539 * Revised SPARC target
1541 The SPARC target has been completely revised, incorporating the
1542 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1543 support for LynxOS and SunOS 4 has been dropped. Calling functions
1544 from within GDB on operating systems with a non-executable stack
1545 (Solaris, OpenBSD) now works.
1549 GDB has a new C++ demangler which does a better job on the mangled
1550 names generated by current versions of g++. It also runs faster, so
1551 with this and other changes gdb should now start faster on large C++
1554 * DWARF 2 Location Expressions
1556 GDB support for location expressions has been extended to support function
1557 arguments and frame bases. Older versions of GDB could crash when they
1560 * C++ nested types and namespaces
1562 GDB's support for nested types and namespaces in C++ has been
1563 improved, especially if you use the DWARF 2 debugging format. (This
1564 is the default for recent versions of GCC on most platforms.)
1565 Specifically, if you have a class "Inner" defined within a class or
1566 namespace "Outer", then GDB realizes that the class's name is
1567 "Outer::Inner", not simply "Inner". This should greatly reduce the
1568 frequency of complaints about not finding RTTI symbols. In addition,
1569 if you are stopped at inside of a function defined within a namespace,
1570 GDB modifies its name lookup accordingly.
1572 * New native configurations
1574 NetBSD/amd64 x86_64-*-netbsd*
1575 OpenBSD/amd64 x86_64-*-openbsd*
1576 OpenBSD/alpha alpha*-*-openbsd*
1577 OpenBSD/sparc sparc-*-openbsd*
1578 OpenBSD/sparc64 sparc64-*-openbsd*
1580 * New debugging protocols
1582 M32R with SDI protocol m32r-*-elf*
1584 * "set prompt-escape-char" command deleted.
1586 The command "set prompt-escape-char" has been deleted. This command,
1587 and its very obscure effet on GDB's prompt, was never documented,
1588 tested, nor mentioned in the NEWS file.
1590 * OBSOLETE configurations and files
1592 Configurations that have been declared obsolete in this release have
1593 been commented out. Unless there is activity to revive these
1594 configurations, the next release of GDB will have their sources
1595 permanently REMOVED.
1597 Sun 3, running SunOS 3 m68*-*-sunos3*
1598 Sun 3, running SunOS 4 m68*-*-sunos4*
1599 Sun 2, running SunOS 3 m68000-*-sunos3*
1600 Sun 2, running SunOS 4 m68000-*-sunos4*
1601 Motorola 680x0 running LynxOS m68*-*-lynxos*
1602 AT&T 3b1/Unix pc m68*-att-*
1603 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1604 decstation mips-dec-* mips-little-*
1605 riscos mips-*-riscos* mips-*-sysv*
1606 sonymips mips-sony-*
1607 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1609 * REMOVED configurations and files
1611 SGI Irix-4.x mips-sgi-irix4 or iris4
1612 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1613 Z8000 simulator z8k-zilog-none or z8ksim
1614 Matsushita MN10200 w/simulator mn10200-*-*
1615 H8/500 simulator h8500-hitachi-hms or h8500hms
1616 HP/PA running BSD hppa*-*-bsd*
1617 HP/PA running OSF/1 hppa*-*-osf*
1618 HP/PA Pro target hppa*-*-pro*
1619 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1620 386BSD i[3456]86-*-bsd*
1621 Sequent family i[3456]86-sequent-sysv4*
1622 i[3456]86-sequent-sysv*
1623 i[3456]86-sequent-bsd*
1624 SPARC running LynxOS sparc-*-lynxos*
1625 SPARC running SunOS 4 sparc-*-sunos4*
1626 Tsqware Sparclet sparclet-*-*
1627 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1629 *** Changes in GDB 6.0:
1633 Support for debugging the Objective-C programming language has been
1634 integrated into GDB.
1636 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1638 DWARF 2's Call Frame Information makes available compiler generated
1639 information that more exactly describes the program's run-time stack.
1640 By using this information, GDB is able to provide more robust stack
1643 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1644 have been updated to use a new backtrace mechanism which includes
1645 DWARF 2 CFI support.
1649 GDB's remote protocol has been extended to include support for hosted
1650 file I/O (where the remote target uses GDB's file system). See GDB's
1651 remote protocol documentation for details.
1653 * All targets using the new architecture framework.
1655 All of GDB's targets have been updated to use the new internal
1656 architecture framework. The way is now open for future GDB releases
1657 to include cross-architecture native debugging support (i386 on amd64,
1660 * GNU/Linux's Thread Local Storage (TLS)
1662 GDB now includes support for for the GNU/Linux implementation of
1663 per-thread variables.
1665 * GNU/Linux's Native POSIX Thread Library (NPTL)
1667 GDB's thread code has been updated to work with either the new
1668 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1670 * Separate debug info.
1672 GDB, in conjunction with BINUTILS, now supports a mechanism for
1673 automatically loading debug information from a separate file. Instead
1674 of shipping full debug and non-debug versions of system libraries,
1675 system integrators can now instead ship just the stripped libraries
1676 and optional debug files.
1678 * DWARF 2 Location Expressions
1680 DWARF 2 Location Expressions allow the compiler to more completely
1681 describe the location of variables (even in optimized code) to the
1684 GDB now includes preliminary support for location expressions (support
1685 for DW_OP_piece is still missing).
1689 A number of long standing bugs that caused GDB to die while starting a
1690 Java application have been fixed. GDB's Java support is now
1691 considered "useable".
1693 * GNU/Linux support for fork, vfork, and exec.
1695 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1696 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1699 * GDB supports logging output to a file
1701 There are two new commands, "set logging" and "show logging", which can be
1702 used to capture GDB's output to a file.
1704 * The meaning of "detach" has changed for gdbserver
1706 The "detach" command will now resume the application, as documented. To
1707 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1710 * d10v, m68hc11 `regs' command deprecated
1712 The `info registers' command has been updated so that it displays the
1713 registers using a format identical to the old `regs' command.
1717 A new command, "maint set profile on/off", has been added. This command can
1718 be used to enable or disable profiling while running GDB, to profile a
1719 session or a set of commands. In addition there is a new configure switch,
1720 "--enable-profiling", which will cause GDB to be compiled with profiling
1721 data, for more informative profiling results.
1723 * Default MI syntax changed to "mi2".
1725 The default MI (machine interface) syntax, enabled by the command line
1726 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1727 "mi1", can be enabled by specifying the option "-i=mi1".
1729 Support for the original "mi0" syntax (included in GDB 5.0) has been
1732 Fix for gdb/192: removed extraneous space when displaying frame level.
1733 Fix for gdb/672: update changelist is now output in mi list format.
1734 Fix for gdb/702: a -var-assign that updates the value now shows up
1735 in a subsequent -var-update.
1737 * New native configurations.
1739 FreeBSD/amd64 x86_64-*-freebsd*
1741 * Multi-arched targets.
1743 HP/PA HPUX11 hppa*-*-hpux*
1744 Renesas M32R/D w/simulator m32r-*-elf*
1746 * OBSOLETE configurations and files
1748 Configurations that have been declared obsolete in this release have
1749 been commented out. Unless there is activity to revive these
1750 configurations, the next release of GDB will have their sources
1751 permanently REMOVED.
1753 Z8000 simulator z8k-zilog-none or z8ksim
1754 Matsushita MN10200 w/simulator mn10200-*-*
1755 H8/500 simulator h8500-hitachi-hms or h8500hms
1756 HP/PA running BSD hppa*-*-bsd*
1757 HP/PA running OSF/1 hppa*-*-osf*
1758 HP/PA Pro target hppa*-*-pro*
1759 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1760 Sequent family i[3456]86-sequent-sysv4*
1761 i[3456]86-sequent-sysv*
1762 i[3456]86-sequent-bsd*
1763 Tsqware Sparclet sparclet-*-*
1764 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1766 * REMOVED configurations and files
1769 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1770 IBM AIX PS/2 i[3456]86-*-aix
1771 i386 running Mach 3.0 i[3456]86-*-mach3*
1772 i386 running Mach i[3456]86-*-mach*
1773 i386 running OSF/1 i[3456]86-*osf1mk*
1774 HP/Apollo 68k Family m68*-apollo*-sysv*,
1776 m68*-hp-bsd*, m68*-hp-hpux*
1777 Argonaut Risc Chip (ARC) arc-*-*
1778 Mitsubishi D30V d30v-*-*
1779 Fujitsu FR30 fr30-*-elf*
1780 OS/9000 i[34]86-*-os9k
1781 I960 with MON960 i960-*-coff
1783 * MIPS $fp behavior changed
1785 The convenience variable $fp, for the MIPS, now consistently returns
1786 the address of the current frame's base. Previously, depending on the
1787 context, $fp could refer to either $sp or the current frame's base
1788 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1789 The GNU Source-Level Debugger''.
1791 *** Changes in GDB 5.3:
1793 * GNU/Linux shared library multi-threaded performance improved.
1795 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1796 `/proc', in preference to `ptrace' for memory reads. This may result
1797 in an improvement in the start-up time of multi-threaded, shared
1798 library applications when run under GDB. One GDB user writes: ``loads
1799 shared libs like mad''.
1801 * ``gdbserver'' now supports multi-threaded applications on some targets
1803 Support for debugging multi-threaded applications which use
1804 the GNU/Linux LinuxThreads package has been added for
1805 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1806 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1808 * GDB now supports C/C++ preprocessor macros.
1810 GDB now expands preprocessor macro invocations in C/C++ expressions,
1811 and provides various commands for showing macro definitions and how
1814 The new command `macro expand EXPRESSION' expands any macro
1815 invocations in expression, and shows the result.
1817 The new command `show macro MACRO-NAME' shows the definition of the
1818 macro named MACRO-NAME, and where it was defined.
1820 Most compilers don't include information about macros in the debugging
1821 information by default. In GCC 3.1, for example, you need to compile
1822 your program with the options `-gdwarf-2 -g3'. If the macro
1823 information is present in the executable, GDB will read it.
1825 * Multi-arched targets.
1827 DEC Alpha (partial) alpha*-*-*
1828 DEC VAX (partial) vax-*-*
1830 National Semiconductor NS32000 (partial) ns32k-*-*
1831 Motorola 68000 (partial) m68k-*-*
1832 Motorola MCORE mcore-*-*
1836 Fujitsu FRV architecture added by Red Hat frv*-*-*
1839 * New native configurations
1841 Alpha NetBSD alpha*-*-netbsd*
1842 SH NetBSD sh*-*-netbsdelf*
1843 MIPS NetBSD mips*-*-netbsd*
1844 UltraSPARC NetBSD sparc64-*-netbsd*
1846 * OBSOLETE configurations and files
1848 Configurations that have been declared obsolete in this release have
1849 been commented out. Unless there is activity to revive these
1850 configurations, the next release of GDB will have their sources
1851 permanently REMOVED.
1853 Mitsubishi D30V d30v-*-*
1854 OS/9000 i[34]86-*-os9k
1855 IBM AIX PS/2 i[3456]86-*-aix
1856 Fujitsu FR30 fr30-*-elf*
1857 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1858 Argonaut Risc Chip (ARC) arc-*-*
1859 i386 running Mach 3.0 i[3456]86-*-mach3*
1860 i386 running Mach i[3456]86-*-mach*
1861 i386 running OSF/1 i[3456]86-*osf1mk*
1862 HP/Apollo 68k Family m68*-apollo*-sysv*,
1864 m68*-hp-bsd*, m68*-hp-hpux*
1865 I960 with MON960 i960-*-coff
1867 * OBSOLETE languages
1869 CHILL, a Pascal like language used by telecommunications companies.
1871 * REMOVED configurations and files
1873 AMD 29k family via UDI a29k-amd-udi, udi29k
1874 A29K VxWorks a29k-*-vxworks
1875 AMD 29000 embedded, using EBMON a29k-none-none
1876 AMD 29000 embedded with COFF a29k-none-coff
1877 AMD 29000 embedded with a.out a29k-none-aout
1879 testsuite/gdb.hp/gdb.threads-hp/ directory
1881 * New command "set max-user-call-depth <nnn>"
1883 This command allows the user to limit the call depth of user-defined
1884 commands. The default is 1024.
1886 * Changes in FreeBSD/i386 native debugging.
1888 Support for the "generate-core-file" has been added.
1890 * New commands "dump", "append", and "restore".
1892 These commands allow data to be copied from target memory
1893 to a bfd-format or binary file (dump and append), and back
1894 from a file into memory (restore).
1896 * Improved "next/step" support on multi-processor Alpha Tru64.
1898 The previous single-step mechanism could cause unpredictable problems,
1899 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1900 of a software single-step mechanism prevents this.
1902 *** Changes in GDB 5.2.1:
1910 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1911 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1912 Fix, by Joel Brobecker imported from mainline.
1914 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1915 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1916 Fix, by Fred Fish, imported from mainline.
1918 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1919 Surprisingly enough, it works now.
1920 By Michal Ludvig, imported from mainline.
1922 i386 hardware watchpoint support:
1923 avoid misses on second run for some targets.
1924 By Pierre Muller, imported from mainline.
1926 *** Changes in GDB 5.2:
1928 * New command "set trust-readonly-sections on[off]".
1930 This command is a hint that tells gdb that read-only sections
1931 really are read-only (ie. that their contents will not change).
1932 In this mode, gdb will go to the object file rather than the
1933 target to read memory from read-only sections (such as ".text").
1934 This can be a significant performance improvement on some
1935 (notably embedded) targets.
1937 * New command "generate-core-file" (or "gcore").
1939 This new gdb command allows the user to drop a core file of the child
1940 process state at any time. So far it's been implemented only for
1941 GNU/Linux and Solaris, but should be relatively easily ported to other
1942 hosts. Argument is core file name (defaults to core.<pid>).
1944 * New command line option
1946 GDB now accepts --pid or -p followed by a process id.
1948 * Change in command line behavior -- corefiles vs. process ids.
1950 There is a subtle behavior in the way in which GDB handles
1951 command line arguments. The first non-flag argument is always
1952 a program to debug, but the second non-flag argument may either
1953 be a corefile or a process id. Previously, GDB would attempt to
1954 open the second argument as a corefile, and if that failed, would
1955 issue a superfluous error message and then attempt to attach it as
1956 a process. Now, if the second argument begins with a non-digit,
1957 it will be treated as a corefile. If it begins with a digit,
1958 GDB will attempt to attach it as a process, and if no such process
1959 is found, will then attempt to open it as a corefile.
1961 * Changes in ARM configurations.
1963 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1964 configuration is fully multi-arch.
1966 * New native configurations
1968 ARM NetBSD arm*-*-netbsd*
1969 x86 OpenBSD i[3456]86-*-openbsd*
1970 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1971 Sparc64 running FreeBSD sparc64-*-freebsd*
1975 Sanyo XStormy16 xstormy16-elf
1977 * OBSOLETE configurations and files
1979 Configurations that have been declared obsolete in this release have
1980 been commented out. Unless there is activity to revive these
1981 configurations, the next release of GDB will have their sources
1982 permanently REMOVED.
1984 AMD 29k family via UDI a29k-amd-udi, udi29k
1985 A29K VxWorks a29k-*-vxworks
1986 AMD 29000 embedded, using EBMON a29k-none-none
1987 AMD 29000 embedded with COFF a29k-none-coff
1988 AMD 29000 embedded with a.out a29k-none-aout
1990 testsuite/gdb.hp/gdb.threads-hp/ directory
1992 * REMOVED configurations and files
1994 TI TMS320C80 tic80-*-*
1996 PowerPC Solaris powerpcle-*-solaris*
1997 PowerPC Windows NT powerpcle-*-cygwin32
1998 PowerPC Netware powerpc-*-netware*
1999 Harris/CXUX m88k m88*-harris-cxux*
2000 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2001 ns32k-utek-sysv* ns32k-utek-*
2002 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2003 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2004 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2005 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2006 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2008 * Changes to command line processing
2010 The new `--args' feature can be used to specify command-line arguments
2011 for the inferior from gdb's command line.
2013 * Changes to key bindings
2015 There is a new `operate-and-get-next' function bound to `C-o'.
2017 *** Changes in GDB 5.1.1
2019 Fix compile problem on DJGPP.
2021 Fix a problem with floating-point registers on the i386 being
2024 Fix to stop GDB crashing on .debug_str debug info.
2026 Numerous documentation fixes.
2028 Numerous testsuite fixes.
2030 *** Changes in GDB 5.1:
2032 * New native configurations
2034 Alpha FreeBSD alpha*-*-freebsd*
2035 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2036 MIPS GNU/Linux mips*-*-linux*
2037 MIPS SGI Irix 6.x mips*-sgi-irix6*
2038 ia64 AIX ia64-*-aix*
2039 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2043 Motorola 68HC11 and 68HC12 m68hc11-elf
2045 UltraSparc running GNU/Linux sparc64-*-linux*
2047 * OBSOLETE configurations and files
2049 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2050 Harris/CXUX m88k m88*-harris-cxux*
2051 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2052 ns32k-utek-sysv* ns32k-utek-*
2053 TI TMS320C80 tic80-*-*
2055 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2056 PowerPC Solaris powerpcle-*-solaris*
2057 PowerPC Windows NT powerpcle-*-cygwin32
2058 PowerPC Netware powerpc-*-netware*
2059 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2060 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2061 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2062 Apple Macintosh (MPW) host N/A
2064 stuff.c (Program to stuff files into a specially prepared space in kdb)
2065 kdb-start.c (Main loop for the standalone kernel debugger)
2067 Configurations that have been declared obsolete in this release have
2068 been commented out. Unless there is activity to revive these
2069 configurations, the next release of GDB will have their sources
2070 permanently REMOVED.
2072 * REMOVED configurations and files
2074 Altos 3068 m68*-altos-*
2075 Convex c1-*-*, c2-*-*
2077 ARM RISCix arm-*-* (as host)
2081 * GDB has been converted to ISO C.
2083 GDB's source code has been converted to ISO C. In particular, the
2084 sources are fully protoized, and rely on standard headers being
2089 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2091 * The MI enabled by default.
2093 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2094 revised and enabled by default. Packages which use GDB as a debugging
2095 engine behind a UI or another front end are encouraged to switch to
2096 using the GDB/MI interface, instead of the old annotations interface
2097 which is now deprecated.
2099 * Support for debugging Pascal programs.
2101 GDB now includes support for debugging Pascal programs. The following
2102 main features are supported:
2104 - Pascal-specific data types such as sets;
2106 - automatic recognition of Pascal sources based on file-name
2109 - Pascal-style display of data types, variables, and functions;
2111 - a Pascal expression parser.
2113 However, some important features are not yet supported.
2115 - Pascal string operations are not supported at all;
2117 - there are some problems with boolean types;
2119 - Pascal type hexadecimal constants are not supported
2120 because they conflict with the internal variables format;
2122 - support for Pascal objects and classes is not full yet;
2124 - unlike Pascal, GDB is case-sensitive for symbol names.
2126 * Changes in completion.
2128 Commands such as `shell', `run' and `set args', which pass arguments
2129 to inferior programs, now complete on file names, similar to what
2130 users expect at the shell prompt.
2132 Commands which accept locations, such as `disassemble', `print',
2133 `breakpoint', `until', etc. now complete on filenames as well as
2134 program symbols. Thus, if you type "break foob TAB", and the source
2135 files linked into the programs include `foobar.c', that file name will
2136 be one of the candidates for completion. However, file names are not
2137 considered for completion after you typed a colon that delimits a file
2138 name from a name of a function in that file, as in "break foo.c:bar".
2140 `set demangle-style' completes on available demangling styles.
2142 * New platform-independent commands:
2144 It is now possible to define a post-hook for a command as well as a
2145 hook that runs before the command. For more details, see the
2146 documentation of `hookpost' in the GDB manual.
2148 * Changes in GNU/Linux native debugging.
2150 Support for debugging multi-threaded programs has been completely
2151 revised for all platforms except m68k and sparc. You can now debug as
2152 many threads as your system allows you to have.
2154 Attach/detach is supported for multi-threaded programs.
2156 Support for SSE registers was added for x86. This doesn't work for
2157 multi-threaded programs though.
2159 * Changes in MIPS configurations.
2161 Multi-arch support is enabled for all MIPS configurations.
2163 GDB can now be built as native debugger on SGI Irix 6.x systems for
2164 debugging n32 executables. (Debugging 64-bit executables is not yet
2167 * Unified support for hardware watchpoints in all x86 configurations.
2169 Most (if not all) native x86 configurations support hardware-assisted
2170 breakpoints and watchpoints in a unified manner. This support
2171 implements debug register sharing between watchpoints, which allows to
2172 put a virtually infinite number of watchpoints on the same address,
2173 and also supports watching regions up to 16 bytes with several debug
2176 The new maintenance command `maintenance show-debug-regs' toggles
2177 debugging print-outs in functions that insert, remove, and test
2178 watchpoints and hardware breakpoints.
2180 * Changes in the DJGPP native configuration.
2182 New command ``info dos sysinfo'' displays assorted information about
2183 the CPU, OS, memory, and DPMI server.
2185 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2186 display information about segment descriptors stored in GDT, LDT, and
2189 New commands ``info dos pde'' and ``info dos pte'' display entries
2190 from Page Directory and Page Tables (for now works with CWSDPMI only).
2191 New command ``info dos address-pte'' displays the Page Table entry for
2192 a given linear address.
2194 GDB can now pass command lines longer than 126 characters to the
2195 program being debugged (requires an update to the libdbg.a library
2196 which is part of the DJGPP development kit).
2198 DWARF2 debug info is now supported.
2200 It is now possible to `step' and `next' through calls to `longjmp'.
2202 * Changes in documentation.
2204 All GDB documentation was converted to GFDL, the GNU Free
2205 Documentation License.
2207 Tracepoints-related commands are now fully documented in the GDB
2210 TUI, the Text-mode User Interface, is now documented in the manual.
2212 Tracepoints-related commands are now fully documented in the GDB
2215 The "GDB Internals" manual now has an index. It also includes
2216 documentation of `ui_out' functions, GDB coding standards, x86
2217 hardware watchpoints, and memory region attributes.
2219 * GDB's version number moved to ``version.in''
2221 The Makefile variable VERSION has been replaced by the file
2222 ``version.in''. People creating GDB distributions should update the
2223 contents of this file.
2227 GUD support is now a standard part of the EMACS distribution.
2229 *** Changes in GDB 5.0:
2231 * Improved support for debugging FP programs on x86 targets
2233 Unified and much-improved support for debugging floating-point
2234 programs on all x86 targets. In particular, ``info float'' now
2235 displays the FP registers in the same format on all x86 targets, with
2236 greater level of detail.
2238 * Improvements and bugfixes in hardware-assisted watchpoints
2240 It is now possible to watch array elements, struct members, and
2241 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2242 on x86 targets no longer erroneously trigger when the address is
2245 * Improvements in the native DJGPP version of GDB
2247 The distribution now includes all the scripts and auxiliary files
2248 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2249 machines ``out of the box''.
2251 The DJGPP version can now debug programs that use signals. It is
2252 possible to catch signals that happened in the debuggee, deliver
2253 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2254 would kill the program being debugged.) Programs that hook hardware
2255 interrupts (keyboard, timer, etc.) can also be debugged.
2257 It is now possible to debug DJGPP programs that redirect their
2258 standard handles or switch them to raw (as opposed to cooked) mode, or
2259 even close them. The command ``run < foo > bar'' works as expected,
2260 and ``info terminal'' reports useful information about the debuggee's
2261 terminal, including raw/cooked mode, redirection, etc.
2263 The DJGPP version now uses termios functions for console I/O, which
2264 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2267 DOS-style file names with drive letters are now fully supported by
2270 It is now possible to debug DJGPP programs that switch their working
2271 directory. It is also possible to rerun the debuggee any number of
2272 times without restarting GDB; thus, you can use the same setup,
2273 breakpoints, etc. for many debugging sessions.
2275 * New native configurations
2277 ARM GNU/Linux arm*-*-linux*
2278 PowerPC GNU/Linux powerpc-*-linux*
2282 Motorola MCore mcore-*-*
2283 x86 VxWorks i[3456]86-*-vxworks*
2284 PowerPC VxWorks powerpc-*-vxworks*
2285 TI TMS320C80 tic80-*-*
2287 * OBSOLETE configurations
2289 Altos 3068 m68*-altos-*
2290 Convex c1-*-*, c2-*-*
2292 ARM RISCix arm-*-* (as host)
2295 Configurations that have been declared obsolete will be commented out,
2296 but the code will be left in place. If there is no activity to revive
2297 these configurations before the next release of GDB, the sources will
2298 be permanently REMOVED.
2300 * Gould support removed
2302 Support for the Gould PowerNode and NP1 has been removed.
2304 * New features for SVR4
2306 On SVR4 native platforms (such as Solaris), if you attach to a process
2307 without first loading a symbol file, GDB will now attempt to locate and
2308 load symbols from the running process's executable file.
2310 * Many C++ enhancements
2312 C++ support has been greatly improved. Overload resolution now works properly
2313 in almost all cases. RTTI support is on the way.
2315 * Remote targets can connect to a sub-program
2317 A popen(3) style serial-device has been added. This device starts a
2318 sub-process (such as a stand-alone simulator) and then communicates
2319 with that. The sub-program to run is specified using the syntax
2320 ``|<program> <args>'' vis:
2322 (gdb) set remotedebug 1
2323 (gdb) target extended-remote |mn10300-elf-sim program-args
2325 * MIPS 64 remote protocol
2327 A long standing bug in the mips64 remote protocol where by GDB
2328 expected certain 32 bit registers (ex SR) to be transfered as 32
2329 instead of 64 bits has been fixed.
2331 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2332 added to provide backward compatibility with older versions of GDB.
2334 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2336 The command ``set remotebinarydownload'' command has been replaced by
2337 ``set remote X-packet''. Other commands in ``set remote'' family
2338 include ``set remote P-packet''.
2340 * Breakpoint commands accept ranges.
2342 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2343 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2344 ``tracepoint passcount'' also accepts a range of tracepoints.
2346 * ``apropos'' command added.
2348 The ``apropos'' command searches through command names and
2349 documentation strings, printing out matches, making it much easier to
2350 try to find a command that does what you are looking for.
2354 A new machine oriented interface (MI) has been added to GDB. This
2355 interface is designed for debug environments running GDB as a separate
2356 process. This is part of the long term libGDB project. See the
2357 "GDB/MI" chapter of the GDB manual for further information. It can be
2358 enabled by configuring with:
2360 .../configure --enable-gdbmi
2362 *** Changes in GDB-4.18:
2364 * New native configurations
2366 HP-UX 10.20 hppa*-*-hpux10.20
2367 HP-UX 11.x hppa*-*-hpux11.0*
2368 M68K GNU/Linux m68*-*-linux*
2372 Fujitsu FR30 fr30-*-elf*
2373 Intel StrongARM strongarm-*-*
2374 Mitsubishi D30V d30v-*-*
2376 * OBSOLETE configurations
2378 Gould PowerNode, NP1 np1-*-*, pn-*-*
2380 Configurations that have been declared obsolete will be commented out,
2381 but the code will be left in place. If there is no activity to revive
2382 these configurations before the next release of GDB, the sources will
2383 be permanently REMOVED.
2387 As a compatibility experiment, GDB's source files buildsym.h and
2388 buildsym.c have been converted to pure standard C, no longer
2389 containing any K&R compatibility code. We believe that all systems in
2390 use today either come with a standard C compiler, or have a GCC port
2391 available. If this is not true, please report the affected
2392 configuration to bug-gdb@gnu.org immediately. See the README file for
2393 information about getting a standard C compiler if you don't have one
2398 GDB now uses readline 2.2.
2400 * set extension-language
2402 You can now control the mapping between filename extensions and source
2403 languages by using the `set extension-language' command. For instance,
2404 you can ask GDB to treat .c files as C++ by saying
2405 set extension-language .c c++
2406 The command `info extensions' lists all of the recognized extensions
2407 and their associated languages.
2409 * Setting processor type for PowerPC and RS/6000
2411 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2412 you can use the `set processor' command to specify what variant of the
2413 PowerPC family you are debugging. The command
2417 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2418 following PowerPC and RS6000 variants:
2420 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2421 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2423 403GC IBM PowerPC 403GC
2424 505 Motorola PowerPC 505
2425 860 Motorola PowerPC 860 or 850
2426 601 Motorola PowerPC 601
2427 602 Motorola PowerPC 602
2428 603 Motorola/IBM PowerPC 603 or 603e
2429 604 Motorola PowerPC 604 or 604e
2430 750 Motorola/IBM PowerPC 750 or 750
2432 At the moment, this command just tells GDB what to name the
2433 special-purpose processor registers. Since almost all the affected
2434 registers are inaccessible to user-level programs, this command is
2435 only useful for remote debugging in its present form.
2439 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2440 more extensive support for HP-UX. Added features include shared
2441 library support, kernel threads and hardware watchpoints for 11.00,
2442 support for HP's ANSI C and C++ compilers, and a compatibility mode
2443 for xdb and dbx commands.
2447 HP's donation includes the new concept of catchpoints, which is a
2448 generalization of the old catch command. On HP-UX, it is now possible
2449 to catch exec, fork, and vfork, as well as library loading.
2451 This means that the existing catch command has changed; its first
2452 argument now specifies the type of catch to be set up. See the
2453 output of "help catch" for a list of catchpoint types.
2455 * Debugging across forks
2457 On HP-UX, you can choose which process to debug when a fork() happens
2462 HP has donated a curses-based terminal user interface (TUI). To get
2463 it, build with --enable-tui. Although this can be enabled for any
2464 configuration, at present it only works for native HP debugging.
2466 * GDB remote protocol additions
2468 A new protocol packet 'X' that writes binary data is now available.
2469 Default behavior is to try 'X', then drop back to 'M' if the stub
2470 fails to respond. The settable variable `remotebinarydownload'
2471 allows explicit control over the use of 'X'.
2473 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2474 full 64-bit address. The command
2476 set remoteaddresssize 32
2478 can be used to revert to the old behaviour. For existing remote stubs
2479 the change should not be noticed, as the additional address information
2482 In order to assist in debugging stubs, you may use the maintenance
2483 command `packet' to send any text string to the stub. For instance,
2485 maint packet heythere
2487 sends the packet "$heythere#<checksum>". Note that it is very easy to
2488 disrupt a debugging session by sending the wrong packet at the wrong
2491 The compare-sections command allows you to compare section data on the
2492 target to what is in the executable file without uploading or
2493 downloading, by comparing CRC checksums.
2495 * Tracing can collect general expressions
2497 You may now collect general expressions at tracepoints. This requires
2498 further additions to the target-side stub; see tracepoint.c and
2499 doc/agentexpr.texi for further details.
2501 * mask-address variable for Mips
2503 For Mips targets, you may control the zeroing of the upper 32 bits of
2504 a 64-bit address by entering `set mask-address on'. This is mainly
2505 of interest to users of embedded R4xxx and R5xxx processors.
2507 * Higher serial baud rates
2509 GDB's serial code now allows you to specify baud rates 57600, 115200,
2510 230400, and 460800 baud. (Note that your host system may not be able
2511 to achieve all of these rates.)
2515 The i960 configuration now includes an initial implementation of a
2516 builtin simulator, contributed by Jim Wilson.
2519 *** Changes in GDB-4.17:
2521 * New native configurations
2523 Alpha GNU/Linux alpha*-*-linux*
2524 Unixware 2.x i[3456]86-unixware2*
2525 Irix 6.x mips*-sgi-irix6*
2526 PowerPC GNU/Linux powerpc-*-linux*
2527 PowerPC Solaris powerpcle-*-solaris*
2528 Sparc GNU/Linux sparc-*-linux*
2529 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2533 Argonaut Risc Chip (ARC) arc-*-*
2534 Hitachi H8/300S h8300*-*-*
2535 Matsushita MN10200 w/simulator mn10200-*-*
2536 Matsushita MN10300 w/simulator mn10300-*-*
2537 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2538 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2539 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2540 Mitsubishi D10V w/simulator d10v-*-*
2541 Mitsubishi M32R/D w/simulator m32r-*-elf*
2542 Tsqware Sparclet sparclet-*-*
2543 NEC V850 w/simulator v850-*-*
2545 * New debugging protocols
2547 ARM with RDI protocol arm*-*-*
2548 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2549 DDB and LSI variants of PMON protocol mips*-*-*
2550 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2551 PowerPC with SDS protocol powerpc{,le}-*-eabi
2552 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2556 All configurations can now understand and use the DWARF 2 debugging
2557 format. The choice is automatic, if the symbol file contains DWARF 2
2562 GDB now includes basic Java language support. This support is
2563 only useful with Java compilers that produce native machine code.
2565 * solib-absolute-prefix and solib-search-path
2567 For SunOS and SVR4 shared libraries, you may now set the prefix for
2568 loading absolute shared library symbol files, and the search path for
2569 locating non-absolute shared library symbol files.
2571 * Live range splitting
2573 GDB can now effectively debug code for which GCC has performed live
2574 range splitting as part of its optimization. See gdb/doc/LRS for
2575 more details on the expected format of the stabs information.
2579 GDB's support for the GNU Hurd, including thread debugging, has been
2580 updated to work with current versions of the Hurd.
2584 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2585 instruction set. ARM GDB automatically detects when Thumb
2586 instructions are in use, and adjusts disassembly and backtracing
2591 GDB's MIPS target configurations now handle the MIP16 16-bit
2596 GDB now includes support for overlays; if an executable has been
2597 linked such that multiple sections are based at the same address, GDB
2598 will decide which section to use for symbolic info. You can choose to
2599 control the decision manually, using overlay commands, or implement
2600 additional target-side support and use "overlay load-target" to bring
2601 in the overlay mapping. Do "help overlay" for more detail.
2605 The command "info symbol <address>" displays information about
2606 the symbol at the specified address.
2610 The standard remote protocol now includes an extension that allows
2611 asynchronous collection and display of trace data. This requires
2612 extensive support in the target-side debugging stub. Tracing mode
2613 includes a new interaction mode in GDB and new commands: see the
2614 file tracepoint.c for more details.
2618 Configurations for embedded MIPS now include a simulator contributed
2619 by Cygnus Solutions. The simulator supports the instruction sets
2620 of most MIPS variants.
2624 Sparc configurations may now include the ERC32 simulator contributed
2625 by the European Space Agency. The simulator is not built into
2626 Sparc targets by default; configure with --enable-sim to include it.
2630 For target configurations that may include multiple variants of a
2631 basic architecture (such as MIPS and SH), you may now set the
2632 architecture explicitly. "set arch" sets, "info arch" lists
2633 the possible architectures.
2635 *** Changes in GDB-4.16:
2637 * New native configurations
2639 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2640 M68K NetBSD m68k-*-netbsd*
2641 PowerPC AIX 4.x powerpc-*-aix*
2642 PowerPC MacOS powerpc-*-macos*
2643 PowerPC Windows NT powerpcle-*-cygwin32
2644 RS/6000 AIX 4.x rs6000-*-aix4*
2648 ARM with RDP protocol arm-*-*
2649 I960 with MON960 i960-*-coff
2650 MIPS VxWorks mips*-*-vxworks*
2651 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2652 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2654 Matra Sparclet sparclet-*-*
2658 The powerpc-eabi configuration now includes the PSIM simulator,
2659 contributed by Andrew Cagney, with assistance from Mike Meissner.
2660 PSIM is a very elaborate model of the PowerPC, including not only
2661 basic instruction set execution, but also details of execution unit
2662 performance and I/O hardware. See sim/ppc/README for more details.
2666 GDB now works with Solaris 2.5.
2668 * Windows 95/NT native
2670 GDB will now work as a native debugger on Windows 95 and Windows NT.
2671 To build it from source, you must use the "gnu-win32" environment,
2672 which uses a DLL to emulate enough of Unix to run the GNU tools.
2673 Further information, binaries, and sources are available at
2674 ftp.cygnus.com, under pub/gnu-win32.
2676 * dont-repeat command
2678 If a user-defined command includes the command `dont-repeat', then the
2679 command will not be repeated if the user just types return. This is
2680 useful if the command is time-consuming to run, so that accidental
2681 extra keystrokes don't run the same command many times.
2683 * Send break instead of ^C
2685 The standard remote protocol now includes an option to send a break
2686 rather than a ^C to the target in order to interrupt it. By default,
2687 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2689 * Remote protocol timeout
2691 The standard remote protocol includes a new variable `remotetimeout'
2692 that allows you to set the number of seconds before GDB gives up trying
2693 to read from the target. The default value is 2.
2695 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2697 By default GDB will automatically keep track of objects as they are
2698 loaded and unloaded by the dynamic linker. By using the command `set
2699 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2700 when shared library events occur, thus allowing you to set breakpoints
2701 in shared libraries which are explicitly loaded by the inferior.
2703 Note this feature does not work on hpux8. On hpux9 you must link
2704 /usr/lib/end.o into your program. This feature should work
2705 automatically on hpux10.
2707 * Irix 5.x hardware watchpoint support
2709 Irix 5 configurations now support the use of hardware watchpoints.
2711 * Mips protocol "SYN garbage limit"
2713 When debugging a Mips target using the `target mips' protocol, you
2714 may set the number of characters that GDB will ignore by setting
2715 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2716 every character. The default value is 1050.
2718 * Recording and replaying remote debug sessions
2720 If you set `remotelogfile' to the name of a file, gdb will write to it
2721 a recording of a remote debug session. This recording may then be
2722 replayed back to gdb using "gdbreplay". See gdbserver/README for
2723 details. This is useful when you have a problem with GDB while doing
2724 remote debugging; you can make a recording of the session and send it
2725 to someone else, who can then recreate the problem.
2727 * Speedups for remote debugging
2729 GDB includes speedups for downloading and stepping MIPS systems using
2730 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2731 and more efficient S-record downloading.
2733 * Memory use reductions and statistics collection
2735 GDB now uses less memory and reports statistics about memory usage.
2736 Try the `maint print statistics' command, for example.
2738 *** Changes in GDB-4.15:
2740 * Psymtabs for XCOFF
2742 The symbol reader for AIX GDB now uses partial symbol tables. This
2743 can greatly improve startup time, especially for large executables.
2745 * Remote targets use caching
2747 Remote targets now use a data cache to speed up communication with the
2748 remote side. The data cache could lead to incorrect results because
2749 it doesn't know about volatile variables, thus making it impossible to
2750 debug targets which use memory mapped I/O devices. `set remotecache
2751 off' turns the the data cache off.
2753 * Remote targets may have threads
2755 The standard remote protocol now includes support for multiple threads
2756 in the target system, using new protocol commands 'H' and 'T'. See
2757 gdb/remote.c for details.
2761 If GDB is configured with `--enable-netrom', then it will include
2762 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2763 acts as though it is a bank of ROM on the target board, but you can
2764 write into it over the network. GDB's support consists only of
2765 support for fast loading into the emulated ROM; to debug, you must use
2766 another protocol, such as standard remote protocol. The usual
2767 sequence is something like
2769 target nrom <netrom-hostname>
2771 target remote <netrom-hostname>:1235
2775 GDB now includes support for the Apple Macintosh, as a host only. It
2776 may be run as either an MPW tool or as a standalone application, and
2777 it can debug through the serial port. All the usual GDB commands are
2778 available, but to the target command, you must supply "serial" as the
2779 device type instead of "/dev/ttyXX". See mpw-README in the main
2780 directory for more information on how to build. The MPW configuration
2781 scripts */mpw-config.in support only a few targets, and only the
2782 mips-idt-ecoff target has been tested.
2786 GDB configuration now uses autoconf. This is not user-visible,
2787 but does simplify configuration and building.
2791 GDB now supports hpux10.
2793 *** Changes in GDB-4.14:
2795 * New native configurations
2797 x86 FreeBSD i[345]86-*-freebsd
2798 x86 NetBSD i[345]86-*-netbsd
2799 NS32k NetBSD ns32k-*-netbsd
2800 Sparc NetBSD sparc-*-netbsd
2804 A29K VxWorks a29k-*-vxworks
2805 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2806 CPU32 EST-300 emulator m68*-*-est*
2807 PowerPC ELF powerpc-*-elf
2810 * Alpha OSF/1 support for procfs
2812 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2813 possible to attach to running processes. As the mounting of the /proc
2814 filesystem is optional on the Alpha, GDB automatically determines
2815 the availability of /proc during startup. This can lead to problems
2816 if /proc is unmounted after GDB has been started.
2818 * Arguments to user-defined commands
2820 User commands may accept up to 10 arguments separated by whitespace.
2821 Arguments are accessed within the user command via $arg0..$arg9. A
2824 print $arg0 + $arg1 + $arg2
2826 To execute the command use:
2829 Defines the command "adder" which prints the sum of its three arguments.
2830 Note the arguments are text substitutions, so they may reference variables,
2831 use complex expressions, or even perform inferior function calls.
2833 * New `if' and `while' commands
2835 This makes it possible to write more sophisticated user-defined
2836 commands. Both commands take a single argument, which is the
2837 expression to evaluate, and must be followed by the commands to
2838 execute, one per line, if the expression is nonzero, the list being
2839 terminated by the word `end'. The `if' command list may include an
2840 `else' word, which causes the following commands to be executed only
2841 if the expression is zero.
2843 * Fortran source language mode
2845 GDB now includes partial support for Fortran 77. It will recognize
2846 Fortran programs and can evaluate a subset of Fortran expressions, but
2847 variables and functions may not be handled correctly. GDB will work
2848 with G77, but does not yet know much about symbols emitted by other
2851 * Better HPUX support
2853 Most debugging facilities now work on dynamic executables for HPPAs
2854 running hpux9 or later. You can attach to running dynamically linked
2855 processes, but by default the dynamic libraries will be read-only, so
2856 for instance you won't be able to put breakpoints in them. To change
2857 that behavior do the following before running the program:
2863 This will cause the libraries to be mapped private and read-write.
2864 To revert to the normal behavior, do this:
2870 You cannot set breakpoints or examine data in the library until after
2871 the library is loaded if the function/data symbols do not have
2874 GDB can now also read debug symbols produced by the HP C compiler on
2875 HPPAs (sorry, no C++, Fortran or 68k support).
2877 * Target byte order now dynamically selectable
2879 You can choose which byte order to use with a target system, via the
2880 commands "set endian big" and "set endian little", and you can see the
2881 current setting by using "show endian". You can also give the command
2882 "set endian auto", in which case GDB will use the byte order
2883 associated with the executable. Currently, only embedded MIPS
2884 configurations support dynamic selection of target byte order.
2886 * New DOS host serial code
2888 This version uses DPMI interrupts to handle buffered I/O, so you
2889 no longer need to run asynctsr when debugging boards connected to
2892 *** Changes in GDB-4.13:
2894 * New "complete" command
2896 This lists all the possible completions for the rest of the line, if it
2897 were to be given as a command itself. This is intended for use by emacs.
2899 * Trailing space optional in prompt
2901 "set prompt" no longer adds a space for you after the prompt you set. This
2902 allows you to set a prompt which ends in a space or one that does not.
2904 * Breakpoint hit counts
2906 "info break" now displays a count of the number of times the breakpoint
2907 has been hit. This is especially useful in conjunction with "ignore"; you
2908 can ignore a large number of breakpoint hits, look at the breakpoint info
2909 to see how many times the breakpoint was hit, then run again, ignoring one
2910 less than that number, and this will get you quickly to the last hit of
2913 * Ability to stop printing at NULL character
2915 "set print null-stop" will cause GDB to stop printing the characters of
2916 an array when the first NULL is encountered. This is useful when large
2917 arrays actually contain only short strings.
2919 * Shared library breakpoints
2921 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2922 breakpoints in shared libraries before the executable is run.
2924 * Hardware watchpoints
2926 There is a new hardware breakpoint for the watch command for sparclite
2927 targets. See gdb/sparclite/hw_breakpoint.note.
2929 Hardware watchpoints are also now supported under GNU/Linux.
2933 Annotations have been added. These are for use with graphical interfaces,
2934 and are still experimental. Currently only gdba.el uses these.
2936 * Improved Irix 5 support
2938 GDB now works properly with Irix 5.2.
2940 * Improved HPPA support
2942 GDB now works properly with the latest GCC and GAS.
2944 * New native configurations
2946 Sequent PTX4 i[34]86-sequent-ptx4
2947 HPPA running OSF/1 hppa*-*-osf*
2948 Atari TT running SVR4 m68*-*-sysv4*
2949 RS/6000 LynxOS rs6000-*-lynxos*
2953 OS/9000 i[34]86-*-os9k
2954 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2957 * Hitachi SH7000 and E7000-PC ICE support
2959 There is now support for communicating with the Hitachi E7000-PC ICE.
2960 This is available automatically when GDB is configured for the SH.
2964 As usual, a variety of small fixes and improvements, both generic
2965 and configuration-specific. See the ChangeLog for more detail.
2967 *** Changes in GDB-4.12:
2969 * Irix 5 is now supported
2973 GDB-4.12 on the HPPA has a number of changes which make it unable
2974 to debug the output from the currently released versions of GCC and
2975 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2976 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2977 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2980 *** Changes in GDB-4.11:
2982 * User visible changes:
2986 The "set remotedebug" option is now consistent between the mips remote
2987 target, remote targets using the gdb-specific protocol, UDI (AMD's
2988 debug protocol for the 29k) and the 88k bug monitor. It is now an
2989 integer specifying a debug level (normally 0 or 1, but 2 means more
2990 debugging info for the mips target).
2992 * DEC Alpha native support
2994 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2995 debug info, but GDB works fairly well with the DEC compiler and should
2996 work with a future GCC release. See the README file for a few
2997 Alpha-specific notes.
2999 * Preliminary thread implementation
3001 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3003 * LynxOS native and target support for 386
3005 This release has been hosted on LynxOS 2.2, and also can be configured
3006 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3009 * Improvements in C++ mangling/demangling.
3011 This release has much better g++ debugging, specifically in name
3012 mangling/demangling, virtual function calls, print virtual table,
3013 call methods, ...etc.
3015 *** Changes in GDB-4.10:
3017 * User visible changes:
3019 Remote debugging using the GDB-specific (`target remote') protocol now
3020 supports the `load' command. This is only useful if you have some
3021 other way of getting the stub to the target system, and you can put it
3022 somewhere in memory where it won't get clobbered by the download.
3024 Filename completion now works.
3026 When run under emacs mode, the "info line" command now causes the
3027 arrow to point to the line specified. Also, "info line" prints
3028 addresses in symbolic form (as well as hex).
3030 All vxworks based targets now support a user settable option, called
3031 vxworks-timeout. This option represents the number of seconds gdb
3032 should wait for responses to rpc's. You might want to use this if
3033 your vxworks target is, perhaps, a slow software simulator or happens
3034 to be on the far side of a thin network line.
3038 This release contains support for using a DEC alpha as a GDB host for
3039 cross debugging. Native alpha debugging is not supported yet.
3042 *** Changes in GDB-4.9:
3046 This is the first GDB release which is accompanied by a matching testsuite.
3047 The testsuite requires installation of dejagnu, which should be available
3048 via ftp from most sites that carry GNU software.
3052 'Cfront' style demangling has had its name changed to 'ARM' style, to
3053 emphasize that it was written from the specifications in the C++ Annotated
3054 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3055 disclaimers, it still generated too much confusion with users attempting to
3056 use gdb with AT&T cfront.
3060 GDB now uses a standard remote interface to a simulator library.
3061 So far, the library contains simulators for the Zilog Z8001/2, the
3062 Hitachi H8/300, H8/500 and Super-H.
3064 * New targets supported
3066 H8/300 simulator h8300-hitachi-hms or h8300hms
3067 H8/500 simulator h8500-hitachi-hms or h8500hms
3068 SH simulator sh-hitachi-hms or sh
3069 Z8000 simulator z8k-zilog-none or z8ksim
3070 IDT MIPS board over serial line mips-idt-ecoff
3072 Cross-debugging to GO32 targets is supported. It requires a custom
3073 version of the i386-stub.c module which is integrated with the
3074 GO32 memory extender.
3076 * New remote protocols
3078 MIPS remote debugging protocol.
3080 * New source languages supported
3082 This version includes preliminary support for Chill, a Pascal like language
3083 used by telecommunications companies. Chill support is also being integrated
3084 into the GNU compiler, but we don't know when it will be publically available.
3087 *** Changes in GDB-4.8:
3089 * HP Precision Architecture supported
3091 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3092 version of this support was available as a set of patches from the
3093 University of Utah. GDB does not support debugging of programs
3094 compiled with the HP compiler, because HP will not document their file
3095 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3096 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3098 Many problems in the preliminary version have been fixed.
3100 * Faster and better demangling
3102 We have improved template demangling and fixed numerous bugs in the GNU style
3103 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3104 character types (wchar_t) are now supported. Demangling of each symbol is now
3105 only done once, and is cached when the symbol table for a file is read in.
3106 This results in a small increase in memory usage for C programs, a moderate
3107 increase in memory usage for C++ programs, and a fantastic speedup in
3110 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3111 from the specifications in the Annotated Reference Manual, which AT&T's
3112 compiler does not actually implement.
3114 * G++ multiple inheritance compiler problem
3116 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3117 inheritance lattices was reworked to properly discover ambiguities. We
3118 recently found an example which causes this new algorithm to fail in a
3119 very subtle way, producing bad debug information for those classes.
3120 The file 'gcc.patch' (in this directory) can be applied to gcc to
3121 circumvent the problem. A future GCC release will contain a complete
3124 The previous G++ debug info problem (mentioned below for the gdb-4.7
3125 release) is fixed in gcc version 2.3.2.
3127 * Improved configure script
3129 The `configure' script will now attempt to guess your system type if
3130 you don't supply a host system type. The old scheme of supplying a
3131 host system triplet is preferable over using this. All the magic is
3132 done in the new `config.guess' script. Examine it for details.
3134 We have also brought our configure script much more in line with the FSF's
3135 version. It now supports the --with-xxx options. In particular,
3136 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3137 The resulting GDB will not be able to read arbitrary object file formats --
3138 only the format ``expected'' to be used on the configured target system.
3139 We hope to make this the default in a future release.
3141 * Documentation improvements
3143 There's new internal documentation on how to modify GDB, and how to
3144 produce clean changes to the code. We implore people to read it
3145 before submitting changes.
3147 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3148 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3149 `info' files are also provided. To build `info' files from scratch,
3150 you will need the latest `makeinfo' release, which will be available in
3151 a future texinfo-X.Y release.
3153 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3154 We're not sure exactly which versions have this problem, but it has
3155 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3156 or better. If that isn't possible, there is a patch in
3157 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3158 around this problem.
3162 GDB now supports array constants that can be used in expressions typed in by
3163 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3164 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3167 The new directory `gdb/sparclite' contains a program that demonstrates
3168 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3170 * New native hosts supported
3172 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3173 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3175 * New targets supported
3177 AMD 29k family via UDI a29k-amd-udi or udi29k
3179 * New file formats supported
3181 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3182 HPUX core files, and SCO 3.2v2 core files.
3186 Attaching to processes now works again; thanks for the many bug reports.
3188 We have also stomped on a bunch of core dumps caused by
3189 printf_filtered("%s") problems.
3191 We eliminated a copyright problem on the rpc and ptrace header files
3192 for VxWorks, which was discovered at the last minute during the 4.7
3193 release. You should now be able to build a VxWorks GDB.
3195 You can now interrupt gdb while an attached process is running. This
3196 will cause the attached process to stop, and give control back to GDB.
3198 We fixed problems caused by using too many file descriptors
3199 for reading symbols from object files and libraries. This was
3200 especially a problem for programs that used many (~100) shared
3203 The `step' command now only enters a subroutine if there is line number
3204 information for the subroutine. Otherwise it acts like the `next'
3205 command. Previously, `step' would enter subroutines if there was
3206 any debugging information about the routine. This avoids problems
3207 when using `cc -g1' on MIPS machines.
3209 * Internal improvements
3211 GDB's internal interfaces have been improved to make it easier to support
3212 debugging of multiple languages in the future.
3214 GDB now uses a common structure for symbol information internally.
3215 Minimal symbols (derived from linkage symbols in object files), partial
3216 symbols (from a quick scan of debug information), and full symbols
3217 contain a common subset of information, making it easier to write
3218 shared code that handles any of them.
3220 * New command line options
3222 We now accept --silent as an alias for --quiet.
3226 The memory-mapped-malloc library is now licensed under the GNU Library
3227 General Public License.
3229 *** Changes in GDB-4.7:
3231 * Host/native/target split
3233 GDB has had some major internal surgery to untangle the support for
3234 hosts and remote targets. Now, when you configure GDB for a remote
3235 target, it will no longer load in all of the support for debugging
3236 local programs on the host. When fully completed and tested, this will
3237 ensure that arbitrary host/target combinations are possible.
3239 The primary conceptual shift is to separate the non-portable code in
3240 GDB into three categories. Host specific code is required any time GDB
3241 is compiled on that host, regardless of the target. Target specific
3242 code relates to the peculiarities of the target, but can be compiled on
3243 any host. Native specific code is everything else: it can only be
3244 built when the host and target are the same system. Child process
3245 handling and core file support are two common `native' examples.
3247 GDB's use of /proc for controlling Unix child processes is now cleaner.
3248 It has been split out into a single module under the `target_ops' vector,
3249 plus two native-dependent functions for each system that uses /proc.
3251 * New hosts supported
3253 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3254 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3255 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3257 * New targets supported
3259 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3260 68030 and CPU32 m68030-*-*, m68332-*-*
3262 * New native hosts supported
3264 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3265 (386bsd is not well tested yet)
3266 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3268 * New file formats supported
3270 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3271 supports reading of `a.out.adobe' object files, which are an a.out
3272 format extended with minimal information about multiple sections.
3276 `show copying' is the same as the old `info copying'.
3277 `show warranty' is the same as `info warrantee'.
3278 These were renamed for consistency. The old commands continue to work.
3280 `info handle' is a new alias for `info signals'.
3282 You can now define pre-command hooks, which attach arbitrary command
3283 scripts to any command. The commands in the hook will be executed
3284 prior to the user's command. You can also create a hook which will be
3285 executed whenever the program stops. See gdb.texinfo.
3289 We now deal with Cfront style name mangling, and can even extract type
3290 info from mangled symbols. GDB can automatically figure out which
3291 symbol mangling style your C++ compiler uses.
3293 Calling of methods and virtual functions has been improved as well.
3297 The crash that occured when debugging Sun Ansi-C compiled binaries is
3298 fixed. This was due to mishandling of the extra N_SO stabs output
3301 We also finally got Ultrix 4.2 running in house, and fixed core file
3302 support, with help from a dozen people on the net.
3304 John M. Farrell discovered that the reason that single-stepping was so
3305 slow on all of the Mips based platforms (primarily SGI and DEC) was
3306 that we were trying to demangle and lookup a symbol used for internal
3307 purposes on every instruction that was being stepped through. Changing
3308 the name of that symbol so that it couldn't be mistaken for a C++
3309 mangled symbol sped things up a great deal.
3311 Rich Pixley sped up symbol lookups in general by getting much smarter
3312 about when C++ symbol mangling is necessary. This should make symbol
3313 completion (TAB on the command line) much faster. It's not as fast as
3314 we'd like, but it's significantly faster than gdb-4.6.
3318 A new user controllable variable 'call_scratch_address' can
3319 specify the location of a scratch area to be used when GDB
3320 calls a function in the target. This is necessary because the
3321 usual method of putting the scratch area on the stack does not work
3322 in systems that have separate instruction and data spaces.
3324 We integrated changes to support the 29k UDI (Universal Debugger
3325 Interface), but discovered at the last minute that we didn't have all
3326 of the appropriate copyright paperwork. We are working with AMD to
3327 resolve this, and hope to have it available soon.
3331 We have sped up the remote serial line protocol, especially for targets
3332 with lots of registers. It now supports a new `expedited status' ('T')
3333 message which can be used in place of the existing 'S' status message.
3334 This allows the remote stub to send only the registers that GDB
3335 needs to make a quick decision about single-stepping or conditional
3336 breakpoints, eliminating the need to fetch the entire register set for
3337 each instruction being stepped through.
3339 The GDB remote serial protocol now implements a write-through cache for
3340 registers, only re-reading the registers if the target has run.
3342 There is also a new remote serial stub for SPARC processors. You can
3343 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3344 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3345 processor with a serial port.
3349 Configure.in files have become much easier to read and modify. A new
3350 `table driven' format makes it more obvious what configurations are
3351 supported, and what files each one uses.
3355 There is a new opcodes library which will eventually contain all of the
3356 disassembly routines and opcode tables. At present, it only contains
3357 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3358 disassembler (binutils/objdump) to share these routines.
3360 The libiberty library is now copylefted under the GNU Library General
3361 Public License. This allows more liberal use, and was done so libg++
3362 can use it. This makes no difference to GDB, since the Library License
3363 grants all the rights from the General Public License.
3367 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3368 reference to the stabs symbol info used by the debugger. It is (as far
3369 as we know) the only published document on this fascinating topic. We
3370 encourage you to read it, compare it to the stabs information on your
3371 system, and send improvements on the document in general (to
3372 bug-gdb@prep.ai.mit.edu).
3374 And, of course, many bugs have been fixed.
3377 *** Changes in GDB-4.6:
3379 * Better support for C++ function names
3381 GDB now accepts as input the "demangled form" of C++ overloaded function
3382 names and member function names, and can do command completion on such names
3383 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3384 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3385 Make use of command completion, it is your friend.
3387 GDB also now accepts a variety of C++ mangled symbol formats. They are
3388 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3389 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3390 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3391 for the list of formats.
3393 * G++ symbol mangling problem
3395 Recent versions of gcc have a bug in how they emit debugging information for
3396 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3397 directory) can be applied to gcc to fix the problem. Alternatively, if you
3398 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3399 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3400 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3403 * New 'maintenance' command
3405 All of the commands related to hacking GDB internals have been moved out of
3406 the main command set, and now live behind the 'maintenance' command. This
3407 can also be abbreviated as 'mt'. The following changes were made:
3409 dump-me -> maintenance dump-me
3410 info all-breakpoints -> maintenance info breakpoints
3411 printmsyms -> maintenance print msyms
3412 printobjfiles -> maintenance print objfiles
3413 printpsyms -> maintenance print psymbols
3414 printsyms -> maintenance print symbols
3416 The following commands are new:
3418 maintenance demangle Call internal GDB demangler routine to
3419 demangle a C++ link name and prints the result.
3420 maintenance print type Print a type chain for a given symbol
3422 * Change to .gdbinit file processing
3424 We now read the $HOME/.gdbinit file before processing the argv arguments
3425 (e.g. reading symbol files or core files). This allows global parameters to
3426 be set, which will apply during the symbol reading. The ./.gdbinit is still
3427 read after argv processing.
3429 * New hosts supported
3431 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3433 GNU/Linux support i386-unknown-linux or linux
3435 We are also including code to support the HP/PA running BSD and HPUX. This
3436 is almost guaranteed not to work, as we didn't have time to test or build it
3437 for this release. We are including it so that the more adventurous (or
3438 masochistic) of you can play with it. We also had major problems with the
3439 fact that the compiler that we got from HP doesn't support the -g option.
3442 * New targets supported
3444 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3446 * More smarts about finding #include files
3448 GDB now remembers the compilation directory for all include files, and for
3449 all files from which C is generated (like yacc and lex sources). This
3450 greatly improves GDB's ability to find yacc/lex sources, and include files,
3451 especially if you are debugging your program from a directory different from
3452 the one that contains your sources.
3454 We also fixed a bug which caused difficulty with listing and setting
3455 breakpoints in include files which contain C code. (In the past, you had to
3456 try twice in order to list an include file that you hadn't looked at before.)
3458 * Interesting infernals change
3460 GDB now deals with arbitrary numbers of sections, where the symbols for each
3461 section must be relocated relative to that section's landing place in the
3462 target's address space. This work was needed to support ELF with embedded
3463 stabs used by Solaris-2.0.
3465 * Bug fixes (of course!)
3467 There have been loads of fixes for the following things:
3468 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3469 i960, stabs, DOS(GO32), procfs, etc...
3471 See the ChangeLog for details.
3473 *** Changes in GDB-4.5:
3475 * New machines supported (host and target)
3477 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3479 SGI Irix-4.x mips-sgi-irix4 or iris4
3481 * New malloc package
3483 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3484 Mmalloc is capable of handling mutiple heaps of memory. It is also
3485 capable of saving a heap to a file, and then mapping it back in later.
3486 This can be used to greatly speedup the startup of GDB by using a
3487 pre-parsed symbol table which lives in a mmalloc managed heap. For
3488 more details, please read mmalloc/mmalloc.texi.
3492 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3493 'help info proc' for details.
3495 * MIPS ecoff symbol table format
3497 The code that reads MIPS symbol table format is now supported on all hosts.
3498 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3501 * File name changes for MS-DOS
3503 Many files in the config directories have been renamed to make it easier to
3504 support GDB on MS-DOSe systems (which have very restrictive file name
3505 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3506 environment) is close to working but has some remaining problems. Note
3507 that debugging of DOS programs is not supported, due to limitations
3508 in the ``operating system'', but it can be used to host cross-debugging.
3510 * Cross byte order fixes
3512 Many fixes have been made to support cross debugging of Sparc and MIPS
3513 targets from hosts whose byte order differs.
3515 * New -mapped and -readnow options
3517 If memory-mapped files are available on your system through the 'mmap'
3518 system call, you can use the -mapped option on the `file' or
3519 `symbol-file' commands to cause GDB to write the symbols from your
3520 program into a reusable file. If the program you are debugging is
3521 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3522 Future GDB debugging sessions will notice the presence of this file,
3523 and will quickly map in symbol information from it, rather than reading
3524 the symbol table from the executable program. Using the '-mapped'
3525 option in a GDB `file' or `symbol-file' command has the same effect as
3526 starting GDB with the '-mapped' command-line option.
3528 You can cause GDB to read the entire symbol table immediately by using
3529 the '-readnow' option with any of the commands that load symbol table
3530 information (or on the GDB command line). This makes the command
3531 slower, but makes future operations faster.
3533 The -mapped and -readnow options are typically combined in order to
3534 build a `fred.syms' file that contains complete symbol information.
3535 A simple GDB invocation to do nothing but build a `.syms' file for future
3538 gdb -batch -nx -mapped -readnow programname
3540 The `.syms' file is specific to the host machine on which GDB is run.
3541 It holds an exact image of GDB's internal symbol table. It cannot be
3542 shared across multiple host platforms.
3544 * longjmp() handling
3546 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3547 siglongjmp() without losing control. This feature has not yet been ported to
3548 all systems. It currently works on many 386 platforms, all MIPS-based
3549 platforms (SGI, DECstation, etc), and Sun3/4.
3553 Preliminary work has been put in to support the new Solaris OS from Sun. At
3554 this time, it can control and debug processes, but it is not capable of
3559 As always, many many bug fixes. The major areas were with g++, and mipsread.
3560 People using the MIPS-based platforms should experience fewer mysterious
3561 crashes and trashed symbol tables.
3563 *** Changes in GDB-4.4:
3565 * New machines supported (host and target)
3567 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3569 BSD Reno on Vax vax-dec-bsd
3570 Ultrix on Vax vax-dec-ultrix
3572 * New machines supported (target)
3574 AMD 29000 embedded, using EBMON a29k-none-none
3578 GDB continues to improve its handling of C++. `References' work better.
3579 The demangler has also been improved, and now deals with symbols mangled as
3580 per the Annotated C++ Reference Guide.
3582 GDB also now handles `stabs' symbol information embedded in MIPS
3583 `ecoff' symbol tables. Since the ecoff format was not easily
3584 extensible to handle new languages such as C++, this appeared to be a
3585 good way to put C++ debugging info into MIPS binaries. This option
3586 will be supported in the GNU C compiler, version 2, when it is
3589 * New features for SVR4
3591 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3592 shared libraries. Debugging dynamically linked programs should present
3593 only minor differences from debugging statically linked programs.
3595 The `info proc' command will print out information about any process
3596 on an SVR4 system (including the one you are debugging). At the moment,
3597 it prints the address mappings of the process.
3599 If you bring up GDB on another SVR4 system, please send mail to
3600 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3602 * Better dynamic linking support in SunOS
3604 Reading symbols from shared libraries which contain debugging symbols
3605 now works properly. However, there remain issues such as automatic
3606 skipping of `transfer vector' code during function calls, which
3607 make it harder to debug code in a shared library, than to debug the
3608 same code linked statically.
3612 GDB is now using the latest `getopt' routines from the FSF. This
3613 version accepts the -- prefix for options with long names. GDB will
3614 continue to accept the old forms (-option and +option) as well.
3615 Various single letter abbreviations for options have been explicity
3616 added to the option table so that they won't get overshadowed in the
3617 future by other options that begin with the same letter.
3621 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3622 Many assorted bugs have been handled. Many more remain to be handled.
3623 See the various ChangeLog files (primarily in gdb and bfd) for details.
3626 *** Changes in GDB-4.3:
3628 * New machines supported (host and target)
3630 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3631 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3632 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3634 * Almost SCO Unix support
3636 We had hoped to support:
3637 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3638 (except for core file support), but we discovered very late in the release
3639 that it has problems with process groups that render gdb unusable. Sorry
3640 about that. I encourage people to fix it and post the fixes.
3642 * Preliminary ELF and DWARF support
3644 GDB can read ELF object files on System V Release 4, and can handle
3645 debugging records for C, in DWARF format, in ELF files. This support
3646 is preliminary. If you bring up GDB on another SVR4 system, please
3647 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3652 GDB now uses the latest `readline' library. One user-visible change
3653 is that two tabs will list possible command completions, which previously
3654 required typing M-? (meta-question mark, or ESC ?).
3658 The `stepi' bug that many of you noticed has been squashed.
3659 Many bugs in C++ have been handled. Many more remain to be handled.
3660 See the various ChangeLog files (primarily in gdb and bfd) for details.
3662 * State of the MIPS world (in case you wondered):
3664 GDB can understand the symbol tables emitted by the compilers
3665 supplied by most vendors of MIPS-based machines, including DEC. These
3666 symbol tables are in a format that essentially nobody else uses.
3668 Some versions of gcc come with an assembler post-processor called
3669 mips-tfile. This program is required if you want to do source-level
3670 debugging of gcc-compiled programs. I believe FSF does not ship
3671 mips-tfile with gcc version 1, but it will eventually come with gcc
3674 Debugging of g++ output remains a problem. g++ version 1.xx does not
3675 really support it at all. (If you're lucky, you should be able to get
3676 line numbers and stack traces to work, but no parameters or local
3677 variables.) With some work it should be possible to improve the
3680 When gcc version 2 is released, you will have somewhat better luck.
3681 However, even then you will get confusing results for inheritance and
3684 We will eventually provide full debugging of g++ output on
3685 DECstations. This will probably involve some kind of stabs-in-ecoff
3686 encapulation, but the details have not been worked out yet.
3689 *** Changes in GDB-4.2:
3691 * Improved configuration
3693 Only one copy of `configure' exists now, and it is not self-modifying.
3694 Porting BFD is simpler.
3698 The `step' and `next' commands now only stop at the first instruction
3699 of a source line. This prevents the multiple stops that used to occur
3700 in switch statements, for-loops, etc. `Step' continues to stop if a
3701 function that has debugging information is called within the line.
3705 Lots of small bugs fixed. More remain.
3707 * New host supported (not target)
3709 Intel 386 PC clone running Mach i386-none-mach
3712 *** Changes in GDB-4.1:
3714 * Multiple source language support
3716 GDB now has internal scaffolding to handle several source languages.
3717 It determines the type of each source file from its filename extension,
3718 and will switch expression parsing and number formatting to match the
3719 language of the function in the currently selected stack frame.
3720 You can also specifically set the language to be used, with
3721 `set language c' or `set language modula-2'.
3725 GDB now has preliminary support for the GNU Modula-2 compiler,
3726 currently under development at the State University of New York at
3727 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3728 continue through the fall of 1991 and into 1992.
3730 Other Modula-2 compilers are currently not supported, and attempting to
3731 debug programs compiled with them will likely result in an error as the
3732 symbol table is read. Feel free to work on it, though!
3734 There are hooks in GDB for strict type checking and range checking,
3735 in the `Modula-2 philosophy', but they do not currently work.
3739 GDB can now write to executable and core files (e.g. patch
3740 a variable's value). You must turn this switch on, specify
3741 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3742 by assigning a new value to a variable. Modifications take
3745 * Automatic SunOS shared library reading
3747 When you run your program, GDB automatically determines where its
3748 shared libraries (if any) have been loaded, and reads their symbols.
3749 The `share' command is no longer needed. This also works when
3750 examining core files.
3754 You can specify the number of lines that the `list' command shows.
3757 * New machines supported (host and target)
3759 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3760 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3761 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3763 * New hosts supported (not targets)
3765 IBM RT/PC: romp-ibm-aix or rtpc
3767 * New targets supported (not hosts)
3769 AMD 29000 embedded with COFF a29k-none-coff
3770 AMD 29000 embedded with a.out a29k-none-aout
3771 Ultracomputer remote kernel debug a29k-nyu-kern
3773 * New remote interfaces
3779 *** Changes in GDB-4.0:
3783 Wide output is wrapped at good places to make the output more readable.
3785 Gdb now supports cross-debugging from a host machine of one type to a
3786 target machine of another type. Communication with the target system
3787 is over serial lines. The ``target'' command handles connecting to the
3788 remote system; the ``load'' command will download a program into the
3789 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3790 also supports debugging of realtime processes running under VxWorks,
3791 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3792 stub on the target system.
3794 New CPUs supported include the AMD 29000 and Intel 960.
3796 GDB now reads object files and symbol tables via a ``binary file''
3797 library, which allows a single copy of GDB to debug programs of multiple
3798 object file types such as a.out and coff.
3800 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3801 refcard.dvi and refcard.ps are available to format it).
3804 * Control-Variable user interface simplified
3806 All variables that control the operation of the debugger can be set
3807 by the ``set'' command, and displayed by the ``show'' command.
3809 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3810 ``Show prompt'' produces the response:
3811 Gdb's prompt is new-gdb=>.
3813 What follows are the NEW set commands. The command ``help set'' will
3814 print a complete list of old and new set commands. ``help set FOO''
3815 will give a longer description of the variable FOO. ``show'' will show
3816 all of the variable descriptions and their current settings.
3818 confirm on/off: Enables warning questions for operations that are
3819 hard to recover from, e.g. rerunning the program while
3820 it is already running. Default is ON.
3822 editing on/off: Enables EMACS style command line editing
3823 of input. Previous lines can be recalled with
3824 control-P, the current line can be edited with control-B,
3825 you can search for commands with control-R, etc.
3828 history filename NAME: NAME is where the gdb command history
3829 will be stored. The default is .gdb_history,
3830 or the value of the environment variable
3833 history size N: The size, in commands, of the command history. The
3834 default is 256, or the value of the environment variable
3837 history save on/off: If this value is set to ON, the history file will
3838 be saved after exiting gdb. If set to OFF, the
3839 file will not be saved. The default is OFF.
3841 history expansion on/off: If this value is set to ON, then csh-like
3842 history expansion will be performed on
3843 command line input. The default is OFF.
3845 radix N: Sets the default radix for input and output. It can be set
3846 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3847 in the current radix, so "set radix 10" is always a no-op.
3849 height N: This integer value is the number of lines on a page. Default
3850 is 24, the current `stty rows'' setting, or the ``li#''
3851 setting from the termcap entry matching the environment
3854 width N: This integer value is the number of characters on a line.
3855 Default is 80, the current `stty cols'' setting, or the ``co#''
3856 setting from the termcap entry matching the environment
3859 Note: ``set screensize'' is obsolete. Use ``set height'' and
3860 ``set width'' instead.
3862 print address on/off: Print memory addresses in various command displays,
3863 such as stack traces and structure values. Gdb looks
3864 more ``symbolic'' if you turn this off; it looks more
3865 ``machine level'' with it on. Default is ON.
3867 print array on/off: Prettyprint arrays. New convenient format! Default
3870 print demangle on/off: Print C++ symbols in "source" form if on,
3873 print asm-demangle on/off: Same, for assembler level printouts
3876 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3879 * Support for Epoch Environment.
3881 The epoch environment is a version of Emacs v18 with windowing. One
3882 new command, ``inspect'', is identical to ``print'', except that if you
3883 are running in the epoch environment, the value is printed in its own
3887 * Support for Shared Libraries
3889 GDB can now debug programs and core files that use SunOS shared libraries.
3890 Symbols from a shared library cannot be referenced
3891 before the shared library has been linked with the program (this
3892 happens after you type ``run'' and before the function main() is entered).
3893 At any time after this linking (including when examining core files
3894 from dynamically linked programs), gdb reads the symbols from each
3895 shared library when you type the ``sharedlibrary'' command.
3896 It can be abbreviated ``share''.
3898 sharedlibrary REGEXP: Load shared object library symbols for files
3899 matching a unix regular expression. No argument
3900 indicates to load symbols for all shared libraries.
3902 info sharedlibrary: Status of loaded shared libraries.
3907 A watchpoint stops execution of a program whenever the value of an
3908 expression changes. Checking for this slows down execution
3909 tremendously whenever you are in the scope of the expression, but is
3910 quite useful for catching tough ``bit-spreader'' or pointer misuse
3911 problems. Some machines such as the 386 have hardware for doing this
3912 more quickly, and future versions of gdb will use this hardware.
3914 watch EXP: Set a watchpoint (breakpoint) for an expression.
3916 info watchpoints: Information about your watchpoints.
3918 delete N: Deletes watchpoint number N (same as breakpoints).
3919 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3920 enable N: Re-enables watchpoint number N (same as breakpoints).
3923 * C++ multiple inheritance
3925 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3928 * C++ exception handling
3930 Gdb now supports limited C++ exception handling. Besides the existing
3931 ability to breakpoint on an exception handler, gdb can breakpoint on
3932 the raising of an exception (before the stack is peeled back to the
3935 catch FOO: If there is a FOO exception handler in the dynamic scope,
3936 set a breakpoint to catch exceptions which may be raised there.
3937 Multiple exceptions (``catch foo bar baz'') may be caught.
3939 info catch: Lists all exceptions which may be caught in the
3940 current stack frame.
3943 * Minor command changes
3945 The command ``call func (arg, arg, ...)'' now acts like the print
3946 command, except it does not print or save a value if the function's result
3947 is void. This is similar to dbx usage.
3949 The ``up'' and ``down'' commands now always print the frame they end up
3950 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3951 frames without printing.
3953 * New directory command
3955 'dir' now adds directories to the FRONT of the source search path.
3956 The path starts off empty. Source files that contain debug information
3957 about the directory in which they were compiled can be found even
3958 with an empty path; Sun CC and GCC include this information. If GDB can't
3959 find your source file in the current directory, type "dir .".
3961 * Configuring GDB for compilation
3963 For normal use, type ``./configure host''. See README or gdb.texinfo
3966 GDB now handles cross debugging. If you are remotely debugging between
3967 two different machines, type ``./configure host -target=targ''.
3968 Host is the machine where GDB will run; targ is the machine
3969 where the program that you are debugging will run.