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.
84 * New commands (for set/show, see "New options" below)
86 record save [<FILENAME>]
87 Save a file (in core file format) containing the process record
88 execution log for replay debugging at a later time.
90 record restore <FILENAME>
91 Restore the process record execution log that was saved at an
92 earlier time, for replay debugging.
94 add-inferior [-copies <N>] [-exec <FILENAME>]
97 clone-inferior [-copies <N>] [ID]
98 Make a new inferior ready to execute the same program another
104 maint info program-spaces
105 List the program spaces loaded into GDB.
107 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
108 show remote interrupt-sequence
109 Allow the user to select one of ^C, a BREAK signal or BREAK-g
110 as the sequence to the remote target in order to interrupt the execution.
111 Ctrl-C is a default. Some system prefers BREAK which is high level of
112 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
113 Magic SysRq g. It is BREAK signal and character 'g'.
115 set remote interrupt-on-connect [on | off]
116 show remote interrupt-on-connect
117 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
118 remote target when gdb connects to it. This is needed when you debug
121 set remotebreak [on | off]
123 Deprecated. Use "set/show remote interrupt-sequence" instead.
125 tvariable $NAME [ = EXP ]
126 Create or modify a trace state variable.
129 List trace state variables and their values.
131 delete tvariable $NAME ...
132 Delete one or more trace state variables.
135 Evaluate the given expressions without collecting anything into the
136 trace buffer. (Valid in tracepoint actions only.)
138 ftrace FN / FILE:LINE / *ADDR
139 Define a fast tracepoint at the given function, line, or address.
141 * New expression syntax
143 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
144 GDB now parses 0b101010 identically with 42.
148 set follow-exec-mode new|same
149 show follow-exec-mode
150 Control whether GDB reuses the same inferior across an exec call or
151 creates a new one. This is useful to be able to restart the old
152 executable after the inferior having done an exec call.
154 set default-collect EXPR, ...
156 Define a list of expressions to be collected at each tracepoint.
157 This is a useful way to ensure essential items are not overlooked,
158 such as registers or a critical global variable.
160 set disconnected-tracing
161 show disconnected-tracing
162 If set to 1, the target is instructed to continue tracing if it
163 loses its connection to GDB. If 0, the target is to stop tracing
169 Define a trace state variable.
172 Get the current value of a trace state variable.
175 Set desired tracing behavior upon disconnection.
178 Get data about the tracepoints currently in use.
182 Process record now works correctly with hardware watchpoints.
184 Multiple bug fixes have been made to the mips-irix port, making it
185 much more reliable. In particular:
186 - Debugging threaded applications is now possible again. Previously,
187 GDB would hang while starting the program, or while waiting for
188 the program to stop at a breakpoint.
189 - Attaching to a running process no longer hangs.
190 - An error occurring while loading a core file has been fixed.
191 - Changing the value of the PC register now works again. This fixes
192 problems observed when using the "jump" command, or when calling
193 a function from GDB, or even when assigning a new value to $pc.
194 - With the "finish" and "return" commands, the return value for functions
195 returning a small array is now correctly printed.
196 - It is now possible to break on shared library code which gets executed
197 during a shared library init phase (code executed while executing
198 their .init section). Previously, the breakpoint would have no effect.
199 - GDB is now able to backtrace through the signal handler for
200 non-threaded programs.
202 PIE (Position Independent Executable) programs debugging is now supported.
203 This includes debugging execution of PIC (Position Independent Code) shared
204 libraries although for that, it should be possible to run such libraries as an
207 *** Changes in GDB 7.0
209 * GDB now has an interface for JIT compilation. Applications that
210 dynamically generate code can create symbol files in memory and register
211 them with GDB. For users, the feature should work transparently, and
212 for JIT developers, the interface is documented in the GDB manual in the
213 "JIT Compilation Interface" chapter.
215 * Tracepoints may now be conditional. The syntax is as for
216 breakpoints; either an "if" clause appended to the "trace" command,
217 or the "condition" command is available. GDB sends the condition to
218 the target for evaluation using the same bytecode format as is used
219 for tracepoint actions.
221 * "disassemble" command with a /r modifier, print the raw instructions
222 in hex as well as in symbolic form."
224 * Process record and replay
226 In a architecture environment that supports ``process record and
227 replay'', ``process record and replay'' target can record a log of
228 the process execution, and replay it with both forward and reverse
231 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
232 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
233 set execution-direction {forward|reverse}, for targets that support
236 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
237 feature is available with a native GDB running on kernel version
240 * GDB now has support for multi-byte and wide character sets on the
241 target. Strings whose character type is wchar_t, char16_t, or
242 char32_t are now correctly printed. GDB supports wide- and unicode-
243 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
244 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
245 `printf'. This feature requires iconv to work properly; if your
246 system does not have a working iconv, GDB can use GNU libiconv. See
247 the installation instructions for more information.
249 * GDB now supports automatic retrieval of shared library files from
250 remote targets. To use this feature, specify a system root that begins
251 with the `remote:' prefix, either via the `set sysroot' command or via
252 the `--with-sysroot' configure-time option.
254 * "info sharedlibrary" now takes an optional regex of libraries to show,
255 and it now reports if a shared library has no debugging information.
257 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
258 now complete on file names.
260 * When completing in expressions, gdb will attempt to limit
261 completions to allowable structure or union fields, where appropriate.
262 For instance, consider:
264 # struct example { int f1; double f2; };
265 # struct example variable;
268 If the user types TAB at the end of this command line, the available
269 completions will be "f1" and "f2".
271 * Inlined functions are now supported. They show up in backtraces, and
272 the "step", "next", and "finish" commands handle them automatically.
274 * GDB now supports the token-splicing (##) and stringification (#)
275 operators when expanding macros. It also supports variable-arity
278 * GDB now supports inspecting extra signal information, exported by
279 the new $_siginfo convenience variable. The feature is currently
280 implemented on linux ARM, i386 and amd64.
282 * GDB can now display the VFP floating point registers and NEON vector
283 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
284 can provide these registers (requires Linux 2.6.30 or later). Remote
285 and simulator targets may also provide them.
290 Search memory for a sequence of bytes.
293 Turn off `+'/`-' protocol acknowledgments to permit more efficient
294 operation over reliable transport links. Use of this packet is
295 controlled by the `set remote noack-packet' command.
298 Kill the process with the specified process ID. Use this in preference
299 to `k' when multiprocess protocol extensions are supported.
302 Obtains additional operating system information
306 Read or write additional signal information.
308 * Removed remote protocol undocumented extension
310 An undocumented extension to the remote protocol's `S' stop reply
311 packet that permited the stub to pass a process id was removed.
312 Remote servers should use the `T' stop reply packet instead.
314 * The "disassemble" command now supports an optional /m modifier to print mixed
317 * GDB now supports multiple function calling conventions according to the
318 DWARF-2 DW_AT_calling_convention function attribute.
320 * The SH target utilizes the aforementioned change to distinguish between gcc
321 and Renesas calling convention. It also adds the new CLI commands
322 `set/show sh calling-convention'.
324 * GDB can now read compressed debug sections, as produced by GNU gold
325 with the --compress-debug-sections=zlib flag.
327 * 64-bit core files are now supported on AIX.
329 * Thread switching is now supported on Tru64.
331 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
332 which will be allocated using malloc later in program execution.
334 * The qXfer:libraries:read remote procotol packet now allows passing a
335 list of section offsets.
337 * On GNU/Linux, GDB can now attach to stopped processes. Several race
338 conditions handling signals delivered during attach or thread creation
339 have also been fixed.
341 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
342 From the user's standpoint, all unqualified instances of True and False
343 are treated as the standard definitions, regardless of context.
345 * GDB now parses C++ symbol and type names more flexibly. For
348 template<typename T> class C { };
351 GDB will now correctly handle all of:
353 ptype C<char const *>
355 ptype C<const char *>
358 * New features in the GDB remote stub, gdbserver
360 - The "--wrapper" command-line argument tells gdbserver to use a
361 wrapper program to launch programs for debugging.
363 - On PowerPC and S/390 targets, it is now possible to use a single
364 gdbserver executable to debug both 32-bit and 64-bit programs.
365 (This requires gdbserver itself to be built as a 64-bit executable.)
367 - gdbserver uses the new noack protocol mode for TCP connections to
368 reduce communications latency, if also supported and enabled in GDB.
370 - Support for the sparc64-linux-gnu target is now included in
373 - The amd64-linux build of gdbserver now supports debugging both
374 32-bit and 64-bit programs.
376 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
377 now support hardware watchpoints, and will use them automatically
382 GDB now has support for scripting using Python. Whether this is
383 available is determined at configure time.
385 New GDB commands can now be written in Python.
387 * Ada tasking support
389 Ada tasks can now be inspected in GDB. The following commands have
393 Print the list of Ada tasks.
395 Print detailed information about task number N.
397 Print the task number of the current task.
399 Switch the context of debugging to task number N.
401 * Support for user-defined prefixed commands. The "define" command can
402 add new commands to existing prefixes, e.g. "target".
404 * Multi-inferior, multi-process debugging.
406 GDB now has generalized support for multi-inferior debugging. See
407 "Debugging Multiple Inferiors" in the manual for more information.
408 Although availability still depends on target support, the command
409 set is more uniform now. The GNU/Linux specific multi-forks support
410 has been migrated to this new framework. This implied some user
411 visible changes; see "New commands" and also "Removed commands"
414 * Target descriptions can now describe the target OS ABI. See the
415 "Target Description Format" section in the user manual for more
418 * Target descriptions can now describe "compatible" architectures
419 to indicate that the target can execute applications for a different
420 architecture in addition to those for the main target architecture.
421 See the "Target Description Format" section in the user manual for
424 * Multi-architecture debugging.
426 GDB now includes general supports for debugging applications on
427 hybrid systems that use more than one single processor architecture
428 at the same time. Each such hybrid architecture still requires
429 specific support to be added. The only hybrid architecture supported
430 in this version of GDB is the Cell Broadband Engine.
432 * GDB now supports integrated debugging of Cell/B.E. applications that
433 use both the PPU and SPU architectures. To enable support for hybrid
434 Cell/B.E. debugging, you need to configure GDB to support both the
435 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
436 --enable-targets configure option.
438 * Non-stop mode debugging.
440 For some targets, GDB now supports an optional mode of operation in
441 which you can examine stopped threads while other threads continue
442 to execute freely. This is referred to as non-stop mode, with the
443 old mode referred to as all-stop mode. See the "Non-Stop Mode"
444 section in the user manual for more information.
446 To be able to support remote non-stop debugging, a remote stub needs
447 to implement the non-stop mode remote protocol extensions, as
448 described in the "Remote Non-Stop" section of the user manual. The
449 GDB remote stub, gdbserver, has been adjusted to support these
450 extensions on linux targets.
452 * New commands (for set/show, see "New options" below)
454 catch syscall [NAME(S) | NUMBER(S)]
455 Catch system calls. Arguments, which should be names of system
456 calls or their numbers, mean catch only those syscalls. Without
457 arguments, every syscall will be caught. When the inferior issues
458 any of the specified syscalls, GDB will stop and announce the system
459 call, both when it is called and when its call returns. This
460 feature is currently available with a native GDB running on the
461 Linux Kernel, under the following architectures: x86, x86_64,
462 PowerPC and PowerPC64.
464 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
466 Search memory for a sequence of bytes.
468 maint set python print-stack
469 maint show python print-stack
470 Show a stack trace when an error is encountered in a Python script.
473 Invoke CODE by passing it to the Python interpreter.
478 These allow macros to be defined, undefined, and listed
482 Show operating system information about processes.
485 List the inferiors currently under GDB's control.
488 Switch focus to inferior number NUM.
491 Detach from inferior number NUM.
494 Kill inferior number NUM.
499 show spu stop-on-load
500 Control whether to stop for new SPE threads during Cell/B.E. debugging.
502 set spu auto-flush-cache
503 show spu auto-flush-cache
504 Control whether to automatically flush the software-managed cache
505 during Cell/B.E. debugging.
507 set sh calling-convention
508 show sh calling-convention
509 Control the calling convention used when calling SH target functions.
513 Control display of timestamps with GDB debugging output.
515 set disassemble-next-line
516 show disassemble-next-line
517 Control display of disassembled source lines or instructions when
520 set remote noack-packet
521 show remote noack-packet
522 Set/show the use of remote protocol QStartNoAckMode packet. See above
523 under "New remote packets."
525 set remote query-attached-packet
526 show remote query-attached-packet
527 Control use of remote protocol `qAttached' (query-attached) packet.
529 set remote read-siginfo-object
530 show remote read-siginfo-object
531 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
534 set remote write-siginfo-object
535 show remote write-siginfo-object
536 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
539 set remote reverse-continue
540 show remote reverse-continue
541 Control use of remote protocol 'bc' (reverse-continue) packet.
543 set remote reverse-step
544 show remote reverse-step
545 Control use of remote protocol 'bs' (reverse-step) packet.
547 set displaced-stepping
548 show displaced-stepping
549 Control displaced stepping mode. Displaced stepping is a way to
550 single-step over breakpoints without removing them from the debuggee.
551 Also known as "out-of-line single-stepping".
555 Control display of debugging info for displaced stepping.
557 maint set internal-error
558 maint show internal-error
559 Control what GDB does when an internal error is detected.
561 maint set internal-warning
562 maint show internal-warning
563 Control what GDB does when an internal warning is detected.
568 Use a wrapper program to launch programs for debugging.
570 set multiple-symbols (all|ask|cancel)
571 show multiple-symbols
572 The value of this variable can be changed to adjust the debugger behavior
573 when an expression or a breakpoint location contains an ambiguous symbol
574 name (an overloaded function name, for instance).
576 set breakpoint always-inserted
577 show breakpoint always-inserted
578 Keep breakpoints always inserted in the target, as opposed to inserting
579 them when resuming the target, and removing them when the target stops.
580 This option can improve debugger performance on slow remote targets.
582 set arm fallback-mode (arm|thumb|auto)
583 show arm fallback-mode
584 set arm force-mode (arm|thumb|auto)
586 These commands control how ARM GDB determines whether instructions
587 are ARM or Thumb. The default for both settings is auto, which uses
588 the current CPSR value for instructions without symbols; previous
589 versions of GDB behaved as if "set arm fallback-mode arm".
591 set disable-randomization
592 show disable-randomization
593 Standalone programs run with the virtual address space randomization enabled
594 by default on some platforms. This option keeps the addresses stable across
595 multiple debugging sessions.
599 Control whether other threads are stopped or not when some thread hits
604 Requests that asynchronous execution is enabled in the target, if available.
605 In this case, it's possible to resume target in the background, and interact
606 with GDB while the target is running. "show target-async" displays the
607 current state of asynchronous execution of the target.
609 set target-wide-charset
610 show target-wide-charset
611 The target-wide-charset is the name of the character set that GDB
612 uses when printing characters whose type is wchar_t.
614 set tcp auto-retry (on|off)
616 set tcp connect-timeout
617 show tcp connect-timeout
618 These commands allow GDB to retry failed TCP connections to a remote stub
619 with a specified timeout period; this is useful if the stub is launched
620 in parallel with GDB but may not be ready to accept connections immediately.
622 set libthread-db-search-path
623 show libthread-db-search-path
624 Control list of directories which GDB will search for appropriate
627 set schedule-multiple (on|off)
628 show schedule-multiple
629 Allow GDB to resume all threads of all processes or only threads of
634 Use more aggressive caching for accesses to the stack. This improves
635 performance of remote debugging (particularly backtraces) without
636 affecting correctness.
638 set interactive-mode (on|off|auto)
639 show interactive-mode
640 Control whether GDB runs in interactive mode (on) or not (off).
641 When in interactive mode, GDB waits for the user to answer all
642 queries. Otherwise, GDB does not wait and assumes the default
643 answer. When set to auto (the default), GDB determines which
644 mode to use based on the stdin settings.
649 For program forks, this is replaced by the new more generic `info
650 inferiors' command. To list checkpoints, you can still use the
651 `info checkpoints' command, which was an alias for the `info forks'
655 Replaced by the new `inferior' command. To switch between
656 checkpoints, you can still use the `restart' command, which was an
657 alias for the `fork' command.
660 This is removed, since some targets don't have a notion of
661 processes. To switch between processes, you can still use the
662 `inferior' command using GDB's own inferior number.
665 For program forks, this is replaced by the new more generic `kill
666 inferior' command. To delete a checkpoint, you can still use the
667 `delete checkpoint' command, which was an alias for the `delete
671 For program forks, this is replaced by the new more generic `detach
672 inferior' command. To detach a checkpoint, you can still use the
673 `detach checkpoint' command, which was an alias for the `detach
676 * New native configurations
678 x86/x86_64 Darwin i[34567]86-*-darwin*
680 x86_64 MinGW x86_64-*-mingw*
684 Lattice Mico32 lm32-*
685 x86 DICOS i[34567]86-*-dicos*
686 x86_64 DICOS x86_64-*-dicos*
689 * The GDB remote stub, gdbserver, now supports x86 Windows CE
690 (mingw32ce) debugging.
696 These commands were actually not implemented on any target.
698 *** Changes in GDB 6.8
700 * New native configurations
702 NetBSD/hppa hppa*-*netbsd*
703 Xtensa GNU/Linux xtensa*-*-linux*
707 NetBSD/hppa hppa*-*-netbsd*
708 Xtensa GNU/Lunux xtensa*-*-linux*
710 * Change in command line behavior -- corefiles vs. process ids.
712 When the '-p NUMBER' or '--pid NUMBER' options are used, and
713 attaching to process NUMBER fails, GDB no longer attempts to open a
714 core file named NUMBER. Attaching to a program using the -c option
715 is no longer supported. Instead, use the '-p' or '--pid' options.
717 * GDB can now be built as a native debugger for debugging Windows x86
718 (mingw32) Portable Executable (PE) programs.
720 * Pending breakpoints no longer change their number when their address
723 * GDB now supports breakpoints with multiple locations,
724 including breakpoints on C++ constructors, inside C++ templates,
725 and in inlined functions.
727 * GDB's ability to debug optimized code has been improved. GDB more
728 accurately identifies function bodies and lexical blocks that occupy
729 more than one contiguous range of addresses.
731 * Target descriptions can now describe registers for PowerPC.
733 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
734 registers on PowerPC targets.
736 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
737 targets even when the libthread_db library is not available.
739 * The GDB remote stub, gdbserver, now supports the new file transfer
740 commands (remote put, remote get, and remote delete).
742 * The GDB remote stub, gdbserver, now supports run and attach in
743 extended-remote mode.
745 * hppa*64*-*-hpux11* target broken
746 The debugger is unable to start a program and fails with the following
747 error: "Error trying to get information about dynamic linker".
748 The gdb-6.7 release is also affected.
750 * GDB now supports the --enable-targets= configure option to allow
751 building a single GDB executable that supports multiple remote
752 target architectures.
754 * GDB now supports debugging C and C++ programs which use the
755 Decimal Floating Point extension. In addition, the PowerPC target
756 now has a set of pseudo-registers to inspect decimal float values
757 stored in two consecutive float registers.
759 * The -break-insert MI command can optionally create pending
762 * Improved support for debugging Ada
763 Many improvements to the Ada language support have been made. These
765 - Better support for Ada2005 interface types
766 - Improved handling of arrays and slices in general
767 - Better support for Taft-amendment types
768 - The '{type} ADDRESS' expression is now allowed on the left hand-side
770 - Improved command completion in Ada
773 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
778 set print frame-arguments (all|scalars|none)
779 show print frame-arguments
780 The value of this variable can be changed to control which argument
781 values should be printed by the debugger when displaying a frame.
786 Transfer files to and from a remote target, and delete remote files.
793 Transfer files to and from a remote target, and delete remote files.
802 Open, close, read, write, and delete files on the remote system.
805 Attach to an existing process on the remote system, in extended-remote
809 Run a new process on the remote system, in extended-remote mode.
811 *** Changes in GDB 6.7
813 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
814 bfd, libiberty and opcodes, as revealed by static analysis donated by
815 Coverity, Inc. (http://scan.coverity.com).
817 * When looking up multiply-defined global symbols, GDB will now prefer the
818 symbol definition in the current shared library if it was built using the
819 -Bsymbolic linker option.
821 * When the Text User Interface (TUI) is not configured, GDB will now
822 recognize the -tui command-line option and print a message that the TUI
825 * The GDB remote stub, gdbserver, now has lower overhead for high
826 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
828 * GDB for MIPS targets now autodetects whether a remote target provides
829 32-bit or 64-bit register values.
831 * Support for C++ member pointers has been improved.
833 * GDB now understands XML target descriptions, which specify the
834 target's overall architecture. GDB can read a description from
835 a local file or over the remote serial protocol.
837 * Vectors of single-byte data use a new integer type which is not
838 automatically displayed as character or string data.
840 * The /s format now works with the print command. It displays
841 arrays of single-byte integers and pointers to single-byte integers
844 * Target descriptions can now describe target-specific registers,
845 for architectures which have implemented the support (currently
846 only ARM, M68K, and MIPS).
848 * GDB and the GDB remote stub, gdbserver, now support the XScale
851 * The GDB remote stub, gdbserver, has been updated to support
852 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
853 has been rewritten to use the standard GDB remote protocol.
855 * GDB can now step into C++ functions which are called through thunks.
857 * GDB for the Cell/B.E. SPU now supports overlay debugging.
859 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
860 layout. It also supports a TextSeg= and DataSeg= response when only
861 segment base addresses (rather than offsets) are available.
863 * The /i format now outputs any trailing branch delay slot instructions
864 immediately following the last instruction within the count specified.
866 * The GDB remote protocol "T" stop reply packet now supports a
867 "library" response. Combined with the new "qXfer:libraries:read"
868 packet, this response allows GDB to debug shared libraries on targets
869 where the operating system manages the list of loaded libraries (e.g.
870 Windows and SymbianOS).
872 * The GDB remote stub, gdbserver, now supports dynamic link libraries
873 (DLLs) on Windows and Windows CE targets.
875 * GDB now supports a faster verification that a .debug file matches its binary
876 according to its build-id signature, if the signature is present.
882 Enable or disable hardware flow control (RTS/CTS) on the serial port
883 when debugging using remote targets.
885 set mem inaccessible-by-default
886 show mem inaccessible-by-default
887 If the target supplies a memory map, for instance via the remote
888 protocol's "qXfer:memory-map:read" packet, setting this variable
889 prevents GDB from accessing memory outside the memory map. This
890 is useful for targets with memory mapped registers or which react
891 badly to accesses of unmapped address space.
893 set breakpoint auto-hw
894 show breakpoint auto-hw
895 If the target supplies a memory map, for instance via the remote
896 protocol's "qXfer:memory-map:read" packet, setting this variable
897 lets GDB use hardware breakpoints automatically for memory regions
898 where it can not use software breakpoints. This covers both the
899 "break" command and internal breakpoints used for other commands
900 including "next" and "finish".
903 catch exception unhandled
904 Stop the program execution when Ada exceptions are raised.
907 Stop the program execution when an Ada assertion failed.
911 Set an alternate system root for target files. This is a more
912 general version of "set solib-absolute-prefix", which is now
913 an alias to "set sysroot".
916 Provide extended SPU facility status information. This set of
917 commands is available only when debugging the Cell/B.E. SPU
920 * New native configurations
922 OpenBSD/sh sh*-*openbsd*
927 Use the specified local file as an XML target description, and do
928 not query the target for its built-in description.
932 OpenBSD/sh sh*-*-openbsd*
933 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
934 Toshiba Media Processor mep-elf
939 Ignore the specified signals; pass them directly to the debugged program
940 without stopping other threads or reporting them to GDB.
943 Read an XML target description from the target, which describes its
948 Read or write contents of an spufs file on the target system. These
949 packets are available only on the Cell/B.E. SPU architecture.
951 qXfer:libraries:read:
952 Report the loaded shared libraries. Combined with new "T" packet
953 response, this packet allows GDB to debug shared libraries on
954 targets where the operating system manages the list of loaded
955 libraries (e.g. Windows and SymbianOS).
959 Support for these obsolete configurations has been removed.
968 i[34567]86-*-netware*
969 i[34567]86-*-sco3.2v5*
970 i[34567]86-*-sco3.2v4*
972 i[34567]86-*-sysv4.2*
975 i[34567]86-*-unixware2*
976 i[34567]86-*-unixware*
985 * Other removed features
992 Various m68k-only ROM monitors.
999 Various Renesas ROM monitors and debugging interfaces for SH and
1004 Support for a Macraigor serial interface to on-chip debugging.
1005 GDB does not directly support the newer parallel or USB
1010 A debug information format. The predecessor to DWARF 2 and
1011 DWARF 3, which are still supported.
1013 Support for the HP aCC compiler on HP-UX/PA-RISC
1015 SOM-encapsulated symbolic debugging information, automatic
1016 invocation of pxdb, and the aCC custom C++ ABI. This does not
1017 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1018 with aCC can still be debugged on an assembly level.
1020 MIPS ".pdr" sections
1022 A MIPS-specific format used to describe stack frame layout
1023 in debugging information.
1027 GDB could work with an older version of Guile to debug
1028 the interpreter and Scheme programs running in it.
1030 set mips stack-arg-size
1031 set mips saved-gpreg-size
1033 Use "set mips abi" to control parameter passing for MIPS.
1035 *** Changes in GDB 6.6
1040 Cell Broadband Engine SPU spu-elf
1042 * GDB can now be configured as a cross-debugger targeting native Windows
1043 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1044 running on a Windows system over TCP/IP to debug Windows programs.
1046 * The GDB remote stub, gdbserver, has been updated to support Windows and
1047 Cygwin debugging. Both single-threaded and multi-threaded programs are
1050 * The "set trust-readonly-sections" command works again. This command was
1051 broken in GDB 6.3, 6.4, and 6.5.
1053 * The "load" command now supports writing to flash memory, if the remote
1054 stub provides the required support.
1056 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1057 longer requires symbolic debug information (e.g. DWARF-2).
1062 unset substitute-path
1063 show substitute-path
1064 Manage a list of substitution rules that GDB uses to rewrite the name
1065 of the directories where the sources are located. This can be useful
1066 for instance when the sources were moved to a different location
1067 between compilation and debugging.
1071 Print each CLI command as it is executed. Each command is prefixed with
1072 a number of `+' symbols representing the nesting depth.
1073 The source command now has a `-v' option to enable the same feature.
1077 The ARM Demon monitor support (RDP protocol, "target rdp").
1079 Kernel Object Display, an embedded debugging feature which only worked with
1080 an obsolete version of Cisco IOS.
1082 The 'set download-write-size' and 'show download-write-size' commands.
1084 * New remote packets
1087 Tell a stub about GDB client features, and request remote target features.
1088 The first feature implemented is PacketSize, which allows the target to
1089 specify the size of packets it can handle - to minimize the number of
1090 packets required and improve performance when connected to a remote
1094 Fetch an OS auxilliary vector from the remote stub. This packet is a
1095 more efficient replacement for qPart:auxv:read.
1097 qXfer:memory-map:read:
1098 Fetch a memory map from the remote stub, including information about
1099 RAM, ROM, and flash memory devices.
1104 Erase and program a flash memory device.
1106 * Removed remote packets
1109 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1110 used it, and only gdbserver implemented it.
1112 *** Changes in GDB 6.5
1116 Renesas M32C/M16C m32c-elf
1118 Morpho Technologies ms1 ms1-elf
1122 init-if-undefined Initialize a convenience variable, but
1123 only if it doesn't already have a value.
1125 The following commands are presently only implemented for native GNU/Linux:
1127 checkpoint Save a snapshot of the program state.
1129 restart <n> Return the program state to a
1130 previously saved state.
1132 info checkpoints List currently saved checkpoints.
1134 delete-checkpoint <n> Delete a previously saved checkpoint.
1136 set|show detach-on-fork Tell gdb whether to detach from a newly
1137 forked process, or to keep debugging it.
1139 info forks List forks of the user program that
1140 are available to be debugged.
1142 fork <n> Switch to debugging one of several
1143 forks of the user program that are
1144 available to be debugged.
1146 delete-fork <n> Delete a fork from the list of forks
1147 that are available to be debugged (and
1148 kill the forked process).
1150 detach-fork <n> Delete a fork from the list of forks
1151 that are available to be debugged (and
1152 allow the process to continue).
1156 Morpho Technologies ms2 ms1-elf
1158 * Improved Windows host support
1160 GDB now builds as a cross debugger hosted on i686-mingw32, including
1161 native console support, and remote communications using either
1162 network sockets or serial ports.
1164 * Improved Modula-2 language support
1166 GDB can now print most types in the Modula-2 syntax. This includes:
1167 basic types, set types, record types, enumerated types, range types,
1168 pointer types and ARRAY types. Procedure var parameters are correctly
1169 printed and hexadecimal addresses and character constants are also
1170 written in the Modula-2 syntax. Best results can be obtained by using
1171 GNU Modula-2 together with the -gdwarf-2 command line option.
1175 The ARM rdi-share module.
1177 The Netware NLM debug server.
1179 *** Changes in GDB 6.4
1181 * New native configurations
1183 OpenBSD/arm arm*-*-openbsd*
1184 OpenBSD/mips64 mips64-*-openbsd*
1188 Morpho Technologies ms1 ms1-elf
1190 * New command line options
1192 --batch-silent As for --batch, but totally silent.
1193 --return-child-result The debugger will exist with the same value
1194 the child (debugged) program exited with.
1195 --eval-command COMMAND, -ex COMMAND
1196 Execute a single GDB CLI command. This may be
1197 specified multiple times and in conjunction
1198 with the --command (-x) option.
1200 * Deprecated commands removed
1202 The following commands, that were deprecated in 2000, have been
1206 set|show arm disassembly-flavor set|show arm disassembler
1207 othernames set arm disassembler
1208 set|show remotedebug set|show debug remote
1209 set|show archdebug set|show debug arch
1210 set|show eventdebug set|show debug event
1213 * New BSD user-level threads support
1215 It is now possible to debug programs using the user-level threads
1216 library on OpenBSD and FreeBSD. Currently supported (target)
1219 FreeBSD/amd64 x86_64-*-freebsd*
1220 FreeBSD/i386 i386-*-freebsd*
1221 OpenBSD/i386 i386-*-openbsd*
1223 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1224 are not yet supported.
1226 * New support for Matsushita MN10300 w/sim added
1227 (Work in progress). mn10300-elf.
1229 * REMOVED configurations and files
1231 VxWorks and the XDR protocol *-*-vxworks
1232 Motorola MCORE mcore-*-*
1233 National Semiconductor NS32000 ns32k-*-*
1235 * New "set print array-indexes" command
1237 After turning this setting "on", GDB prints the index of each element
1238 when displaying arrays. The default is "off" to preserve the previous
1241 * VAX floating point support
1243 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1245 * User-defined command support
1247 In addition to using $arg0..$arg9 for argument passing, it is now possible
1248 to use $argc to determine now many arguments have been passed. See the
1249 section on user-defined commands in the user manual for more information.
1251 *** Changes in GDB 6.3:
1253 * New command line option
1255 GDB now accepts -l followed by a number to set the timeout for remote
1258 * GDB works with GCC -feliminate-dwarf2-dups
1260 GDB now supports a more compact representation of DWARF-2 debug
1261 information using DW_FORM_ref_addr references. These are produced
1262 by GCC with the option -feliminate-dwarf2-dups and also by some
1263 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1264 to use -feliminate-dwarf2-dups.
1266 * Internationalization
1268 When supported by the host system, GDB will be built with
1269 internationalization (libintl). The task of marking up the sources is
1270 continued, we're looking forward to our first translation.
1274 Initial support for debugging programs compiled with the GNAT
1275 implementation of the Ada programming language has been integrated
1276 into GDB. In this release, support is limited to expression evaluation.
1278 * New native configurations
1280 GNU/Linux/m32r m32r-*-linux-gnu
1284 GDB's remote protocol now includes support for the 'p' packet. This
1285 packet is used to fetch individual registers from a remote inferior.
1287 * END-OF-LIFE registers[] compatibility module
1289 GDB's internal register infrastructure has been completely rewritten.
1290 The new infrastructure making possible the implementation of key new
1291 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1294 GDB 6.3 will be the last release to include the the registers[]
1295 compatibility module that allowed out-of-date configurations to
1296 continue to work. This change directly impacts the following
1306 powerpc bdm protocol
1308 Unless there is activity to revive these configurations, they will be
1309 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1311 * OBSOLETE configurations and files
1313 Configurations that have been declared obsolete in this release have
1314 been commented out. Unless there is activity to revive these
1315 configurations, the next release of GDB will have their sources
1316 permanently REMOVED.
1325 *** Changes in GDB 6.2.1:
1327 * MIPS `break main; run' gave an heuristic-fence-post warning
1329 When attempting to run even a simple program, a warning about
1330 heuristic-fence-post being hit would be reported. This problem has
1333 * MIPS IRIX 'long double' crashed GDB
1335 When examining a long double variable, GDB would get a segmentation
1336 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1337 IRIX long double values).
1341 A bug in the VAX stack code was causing problems with the "next"
1342 command. This problem has been fixed.
1344 *** Changes in GDB 6.2:
1346 * Fix for ``many threads''
1348 On GNU/Linux systems that use the NPTL threads library, a program
1349 rapidly creating and deleting threads would confuse GDB leading to the
1352 ptrace: No such process.
1353 thread_db_get_info: cannot get thread info: generic error
1355 This problem has been fixed.
1357 * "-async" and "-noasync" options removed.
1359 Support for the broken "-noasync" option has been removed (it caused
1362 * New ``start'' command.
1364 This command runs the program until the begining of the main procedure.
1366 * New BSD Kernel Data Access Library (libkvm) interface
1368 Using ``target kvm'' it is now possible to debug kernel core dumps and
1369 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1370 platforms. Currently supported (native-only) configurations are:
1372 FreeBSD/amd64 x86_64-*-freebsd*
1373 FreeBSD/i386 i?86-*-freebsd*
1374 NetBSD/i386 i?86-*-netbsd*
1375 NetBSD/m68k m68*-*-netbsd*
1376 NetBSD/sparc sparc-*-netbsd*
1377 OpenBSD/amd64 x86_64-*-openbsd*
1378 OpenBSD/i386 i?86-*-openbsd*
1379 OpenBSD/m68k m68*-openbsd*
1380 OpenBSD/sparc sparc-*-openbsd*
1382 * Signal trampoline code overhauled
1384 Many generic problems with GDB's signal handling code have been fixed.
1385 These include: backtraces through non-contiguous stacks; recognition
1386 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1387 call; backtrace through a signal trampoline; step into and out of
1388 signal handlers; and single-stepping in the signal trampoline.
1390 Please note that kernel bugs are a limiting factor here. These
1391 features have been shown to work on an s390 GNU/Linux system that
1392 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1394 * Cygwin support for DWARF 2 added.
1396 * New native configurations
1398 GNU/Linux/hppa hppa*-*-linux*
1399 OpenBSD/hppa hppa*-*-openbsd*
1400 OpenBSD/m68k m68*-*-openbsd*
1401 OpenBSD/m88k m88*-*-openbsd*
1402 OpenBSD/powerpc powerpc-*-openbsd*
1403 NetBSD/vax vax-*-netbsd*
1404 OpenBSD/vax vax-*-openbsd*
1406 * END-OF-LIFE frame compatibility module
1408 GDB's internal frame infrastructure has been completely rewritten.
1409 The new infrastructure making it possible to support key new features
1410 including DWARF 2 Call Frame Information. To aid in the task of
1411 migrating old configurations to this new infrastructure, a
1412 compatibility module, that allowed old configurations to continue to
1413 work, was also included.
1415 GDB 6.2 will be the last release to include this frame compatibility
1416 module. This change directly impacts the following configurations:
1426 Unless there is activity to revive these configurations, they will be
1427 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1429 * REMOVED configurations and files
1431 Sun 3, running SunOS 3 m68*-*-sunos3*
1432 Sun 3, running SunOS 4 m68*-*-sunos4*
1433 Sun 2, running SunOS 3 m68000-*-sunos3*
1434 Sun 2, running SunOS 4 m68000-*-sunos4*
1435 Motorola 680x0 running LynxOS m68*-*-lynxos*
1436 AT&T 3b1/Unix pc m68*-att-*
1437 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1438 decstation mips-dec-* mips-little-*
1439 riscos mips-*-riscos* mips-*-sysv*
1440 sonymips mips-sony-*
1441 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1443 *** Changes in GDB 6.1.1:
1445 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1447 The TUI (Text-mode User Interface) is now built as part of a default
1448 GDB configuration. It is enabled by either selecting the TUI with the
1449 command line option "-i=tui" or by running the separate "gdbtui"
1450 program. For more information on the TUI, see the manual "Debugging
1453 * Pending breakpoint support (also included in GDB 6.1)
1455 Support has been added to allow you to specify breakpoints in shared
1456 libraries that have not yet been loaded. If a breakpoint location
1457 cannot be found, and the "breakpoint pending" option is set to auto,
1458 GDB queries you if you wish to make the breakpoint pending on a future
1459 shared-library load. If and when GDB resolves the breakpoint symbol,
1460 the pending breakpoint is removed as one or more regular breakpoints
1463 Pending breakpoints are very useful for GCJ Java debugging.
1465 * Fixed ISO-C build problems
1467 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1468 non ISO-C code that stopped them being built using a more strict ISO-C
1469 compiler (e.g., IBM's C compiler).
1471 * Fixed build problem on IRIX 5
1473 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1474 wasn't able to compile compile on an IRIX 5 system.
1476 * Added execute permission to gdb/gdbserver/configure
1478 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1479 permission. This bug would cause configure to fail on a number of
1480 systems (Solaris, IRIX). Ref: server/519.
1482 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1484 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1485 has been updated to use constant array sizes.
1487 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1489 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1490 its generated DWARF Call Frame Info. This encoding was causing GDB to
1491 panic, that panic has been fixed. Ref: gdb/1628.
1493 * Fixed a problem when examining parameters in shared library code.
1495 When examining parameters in optimized shared library code generated
1496 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1497 not available''. GDB now correctly displays the variable's value.
1499 *** Changes in GDB 6.1:
1501 * Removed --with-mmalloc
1503 Support for the mmalloc memory manager has been removed, as it
1504 conflicted with the internal gdb byte cache.
1506 * Changes in AMD64 configurations
1508 The AMD64 target now includes the %cs and %ss registers. As a result
1509 the AMD64 remote protocol has changed; this affects the floating-point
1510 and SSE registers. If you rely on those registers for your debugging,
1511 you should upgrade gdbserver on the remote side.
1513 * Revised SPARC target
1515 The SPARC target has been completely revised, incorporating the
1516 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1517 support for LynxOS and SunOS 4 has been dropped. Calling functions
1518 from within GDB on operating systems with a non-executable stack
1519 (Solaris, OpenBSD) now works.
1523 GDB has a new C++ demangler which does a better job on the mangled
1524 names generated by current versions of g++. It also runs faster, so
1525 with this and other changes gdb should now start faster on large C++
1528 * DWARF 2 Location Expressions
1530 GDB support for location expressions has been extended to support function
1531 arguments and frame bases. Older versions of GDB could crash when they
1534 * C++ nested types and namespaces
1536 GDB's support for nested types and namespaces in C++ has been
1537 improved, especially if you use the DWARF 2 debugging format. (This
1538 is the default for recent versions of GCC on most platforms.)
1539 Specifically, if you have a class "Inner" defined within a class or
1540 namespace "Outer", then GDB realizes that the class's name is
1541 "Outer::Inner", not simply "Inner". This should greatly reduce the
1542 frequency of complaints about not finding RTTI symbols. In addition,
1543 if you are stopped at inside of a function defined within a namespace,
1544 GDB modifies its name lookup accordingly.
1546 * New native configurations
1548 NetBSD/amd64 x86_64-*-netbsd*
1549 OpenBSD/amd64 x86_64-*-openbsd*
1550 OpenBSD/alpha alpha*-*-openbsd*
1551 OpenBSD/sparc sparc-*-openbsd*
1552 OpenBSD/sparc64 sparc64-*-openbsd*
1554 * New debugging protocols
1556 M32R with SDI protocol m32r-*-elf*
1558 * "set prompt-escape-char" command deleted.
1560 The command "set prompt-escape-char" has been deleted. This command,
1561 and its very obscure effet on GDB's prompt, was never documented,
1562 tested, nor mentioned in the NEWS file.
1564 * OBSOLETE configurations and files
1566 Configurations that have been declared obsolete in this release have
1567 been commented out. Unless there is activity to revive these
1568 configurations, the next release of GDB will have their sources
1569 permanently REMOVED.
1571 Sun 3, running SunOS 3 m68*-*-sunos3*
1572 Sun 3, running SunOS 4 m68*-*-sunos4*
1573 Sun 2, running SunOS 3 m68000-*-sunos3*
1574 Sun 2, running SunOS 4 m68000-*-sunos4*
1575 Motorola 680x0 running LynxOS m68*-*-lynxos*
1576 AT&T 3b1/Unix pc m68*-att-*
1577 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1578 decstation mips-dec-* mips-little-*
1579 riscos mips-*-riscos* mips-*-sysv*
1580 sonymips mips-sony-*
1581 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1583 * REMOVED configurations and files
1585 SGI Irix-4.x mips-sgi-irix4 or iris4
1586 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1587 Z8000 simulator z8k-zilog-none or z8ksim
1588 Matsushita MN10200 w/simulator mn10200-*-*
1589 H8/500 simulator h8500-hitachi-hms or h8500hms
1590 HP/PA running BSD hppa*-*-bsd*
1591 HP/PA running OSF/1 hppa*-*-osf*
1592 HP/PA Pro target hppa*-*-pro*
1593 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1594 386BSD i[3456]86-*-bsd*
1595 Sequent family i[3456]86-sequent-sysv4*
1596 i[3456]86-sequent-sysv*
1597 i[3456]86-sequent-bsd*
1598 SPARC running LynxOS sparc-*-lynxos*
1599 SPARC running SunOS 4 sparc-*-sunos4*
1600 Tsqware Sparclet sparclet-*-*
1601 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1603 *** Changes in GDB 6.0:
1607 Support for debugging the Objective-C programming language has been
1608 integrated into GDB.
1610 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1612 DWARF 2's Call Frame Information makes available compiler generated
1613 information that more exactly describes the program's run-time stack.
1614 By using this information, GDB is able to provide more robust stack
1617 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1618 have been updated to use a new backtrace mechanism which includes
1619 DWARF 2 CFI support.
1623 GDB's remote protocol has been extended to include support for hosted
1624 file I/O (where the remote target uses GDB's file system). See GDB's
1625 remote protocol documentation for details.
1627 * All targets using the new architecture framework.
1629 All of GDB's targets have been updated to use the new internal
1630 architecture framework. The way is now open for future GDB releases
1631 to include cross-architecture native debugging support (i386 on amd64,
1634 * GNU/Linux's Thread Local Storage (TLS)
1636 GDB now includes support for for the GNU/Linux implementation of
1637 per-thread variables.
1639 * GNU/Linux's Native POSIX Thread Library (NPTL)
1641 GDB's thread code has been updated to work with either the new
1642 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1644 * Separate debug info.
1646 GDB, in conjunction with BINUTILS, now supports a mechanism for
1647 automatically loading debug information from a separate file. Instead
1648 of shipping full debug and non-debug versions of system libraries,
1649 system integrators can now instead ship just the stripped libraries
1650 and optional debug files.
1652 * DWARF 2 Location Expressions
1654 DWARF 2 Location Expressions allow the compiler to more completely
1655 describe the location of variables (even in optimized code) to the
1658 GDB now includes preliminary support for location expressions (support
1659 for DW_OP_piece is still missing).
1663 A number of long standing bugs that caused GDB to die while starting a
1664 Java application have been fixed. GDB's Java support is now
1665 considered "useable".
1667 * GNU/Linux support for fork, vfork, and exec.
1669 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1670 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1673 * GDB supports logging output to a file
1675 There are two new commands, "set logging" and "show logging", which can be
1676 used to capture GDB's output to a file.
1678 * The meaning of "detach" has changed for gdbserver
1680 The "detach" command will now resume the application, as documented. To
1681 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1684 * d10v, m68hc11 `regs' command deprecated
1686 The `info registers' command has been updated so that it displays the
1687 registers using a format identical to the old `regs' command.
1691 A new command, "maint set profile on/off", has been added. This command can
1692 be used to enable or disable profiling while running GDB, to profile a
1693 session or a set of commands. In addition there is a new configure switch,
1694 "--enable-profiling", which will cause GDB to be compiled with profiling
1695 data, for more informative profiling results.
1697 * Default MI syntax changed to "mi2".
1699 The default MI (machine interface) syntax, enabled by the command line
1700 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1701 "mi1", can be enabled by specifying the option "-i=mi1".
1703 Support for the original "mi0" syntax (included in GDB 5.0) has been
1706 Fix for gdb/192: removed extraneous space when displaying frame level.
1707 Fix for gdb/672: update changelist is now output in mi list format.
1708 Fix for gdb/702: a -var-assign that updates the value now shows up
1709 in a subsequent -var-update.
1711 * New native configurations.
1713 FreeBSD/amd64 x86_64-*-freebsd*
1715 * Multi-arched targets.
1717 HP/PA HPUX11 hppa*-*-hpux*
1718 Renesas M32R/D w/simulator m32r-*-elf*
1720 * OBSOLETE configurations and files
1722 Configurations that have been declared obsolete in this release have
1723 been commented out. Unless there is activity to revive these
1724 configurations, the next release of GDB will have their sources
1725 permanently REMOVED.
1727 Z8000 simulator z8k-zilog-none or z8ksim
1728 Matsushita MN10200 w/simulator mn10200-*-*
1729 H8/500 simulator h8500-hitachi-hms or h8500hms
1730 HP/PA running BSD hppa*-*-bsd*
1731 HP/PA running OSF/1 hppa*-*-osf*
1732 HP/PA Pro target hppa*-*-pro*
1733 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1734 Sequent family i[3456]86-sequent-sysv4*
1735 i[3456]86-sequent-sysv*
1736 i[3456]86-sequent-bsd*
1737 Tsqware Sparclet sparclet-*-*
1738 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1740 * REMOVED configurations and files
1743 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1744 IBM AIX PS/2 i[3456]86-*-aix
1745 i386 running Mach 3.0 i[3456]86-*-mach3*
1746 i386 running Mach i[3456]86-*-mach*
1747 i386 running OSF/1 i[3456]86-*osf1mk*
1748 HP/Apollo 68k Family m68*-apollo*-sysv*,
1750 m68*-hp-bsd*, m68*-hp-hpux*
1751 Argonaut Risc Chip (ARC) arc-*-*
1752 Mitsubishi D30V d30v-*-*
1753 Fujitsu FR30 fr30-*-elf*
1754 OS/9000 i[34]86-*-os9k
1755 I960 with MON960 i960-*-coff
1757 * MIPS $fp behavior changed
1759 The convenience variable $fp, for the MIPS, now consistently returns
1760 the address of the current frame's base. Previously, depending on the
1761 context, $fp could refer to either $sp or the current frame's base
1762 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1763 The GNU Source-Level Debugger''.
1765 *** Changes in GDB 5.3:
1767 * GNU/Linux shared library multi-threaded performance improved.
1769 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1770 `/proc', in preference to `ptrace' for memory reads. This may result
1771 in an improvement in the start-up time of multi-threaded, shared
1772 library applications when run under GDB. One GDB user writes: ``loads
1773 shared libs like mad''.
1775 * ``gdbserver'' now supports multi-threaded applications on some targets
1777 Support for debugging multi-threaded applications which use
1778 the GNU/Linux LinuxThreads package has been added for
1779 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1780 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1782 * GDB now supports C/C++ preprocessor macros.
1784 GDB now expands preprocessor macro invocations in C/C++ expressions,
1785 and provides various commands for showing macro definitions and how
1788 The new command `macro expand EXPRESSION' expands any macro
1789 invocations in expression, and shows the result.
1791 The new command `show macro MACRO-NAME' shows the definition of the
1792 macro named MACRO-NAME, and where it was defined.
1794 Most compilers don't include information about macros in the debugging
1795 information by default. In GCC 3.1, for example, you need to compile
1796 your program with the options `-gdwarf-2 -g3'. If the macro
1797 information is present in the executable, GDB will read it.
1799 * Multi-arched targets.
1801 DEC Alpha (partial) alpha*-*-*
1802 DEC VAX (partial) vax-*-*
1804 National Semiconductor NS32000 (partial) ns32k-*-*
1805 Motorola 68000 (partial) m68k-*-*
1806 Motorola MCORE mcore-*-*
1810 Fujitsu FRV architecture added by Red Hat frv*-*-*
1813 * New native configurations
1815 Alpha NetBSD alpha*-*-netbsd*
1816 SH NetBSD sh*-*-netbsdelf*
1817 MIPS NetBSD mips*-*-netbsd*
1818 UltraSPARC NetBSD sparc64-*-netbsd*
1820 * OBSOLETE configurations and files
1822 Configurations that have been declared obsolete in this release have
1823 been commented out. Unless there is activity to revive these
1824 configurations, the next release of GDB will have their sources
1825 permanently REMOVED.
1827 Mitsubishi D30V d30v-*-*
1828 OS/9000 i[34]86-*-os9k
1829 IBM AIX PS/2 i[3456]86-*-aix
1830 Fujitsu FR30 fr30-*-elf*
1831 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1832 Argonaut Risc Chip (ARC) arc-*-*
1833 i386 running Mach 3.0 i[3456]86-*-mach3*
1834 i386 running Mach i[3456]86-*-mach*
1835 i386 running OSF/1 i[3456]86-*osf1mk*
1836 HP/Apollo 68k Family m68*-apollo*-sysv*,
1838 m68*-hp-bsd*, m68*-hp-hpux*
1839 I960 with MON960 i960-*-coff
1841 * OBSOLETE languages
1843 CHILL, a Pascal like language used by telecommunications companies.
1845 * REMOVED configurations and files
1847 AMD 29k family via UDI a29k-amd-udi, udi29k
1848 A29K VxWorks a29k-*-vxworks
1849 AMD 29000 embedded, using EBMON a29k-none-none
1850 AMD 29000 embedded with COFF a29k-none-coff
1851 AMD 29000 embedded with a.out a29k-none-aout
1853 testsuite/gdb.hp/gdb.threads-hp/ directory
1855 * New command "set max-user-call-depth <nnn>"
1857 This command allows the user to limit the call depth of user-defined
1858 commands. The default is 1024.
1860 * Changes in FreeBSD/i386 native debugging.
1862 Support for the "generate-core-file" has been added.
1864 * New commands "dump", "append", and "restore".
1866 These commands allow data to be copied from target memory
1867 to a bfd-format or binary file (dump and append), and back
1868 from a file into memory (restore).
1870 * Improved "next/step" support on multi-processor Alpha Tru64.
1872 The previous single-step mechanism could cause unpredictable problems,
1873 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1874 of a software single-step mechanism prevents this.
1876 *** Changes in GDB 5.2.1:
1884 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1885 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1886 Fix, by Joel Brobecker imported from mainline.
1888 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1889 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1890 Fix, by Fred Fish, imported from mainline.
1892 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1893 Surprisingly enough, it works now.
1894 By Michal Ludvig, imported from mainline.
1896 i386 hardware watchpoint support:
1897 avoid misses on second run for some targets.
1898 By Pierre Muller, imported from mainline.
1900 *** Changes in GDB 5.2:
1902 * New command "set trust-readonly-sections on[off]".
1904 This command is a hint that tells gdb that read-only sections
1905 really are read-only (ie. that their contents will not change).
1906 In this mode, gdb will go to the object file rather than the
1907 target to read memory from read-only sections (such as ".text").
1908 This can be a significant performance improvement on some
1909 (notably embedded) targets.
1911 * New command "generate-core-file" (or "gcore").
1913 This new gdb command allows the user to drop a core file of the child
1914 process state at any time. So far it's been implemented only for
1915 GNU/Linux and Solaris, but should be relatively easily ported to other
1916 hosts. Argument is core file name (defaults to core.<pid>).
1918 * New command line option
1920 GDB now accepts --pid or -p followed by a process id.
1922 * Change in command line behavior -- corefiles vs. process ids.
1924 There is a subtle behavior in the way in which GDB handles
1925 command line arguments. The first non-flag argument is always
1926 a program to debug, but the second non-flag argument may either
1927 be a corefile or a process id. Previously, GDB would attempt to
1928 open the second argument as a corefile, and if that failed, would
1929 issue a superfluous error message and then attempt to attach it as
1930 a process. Now, if the second argument begins with a non-digit,
1931 it will be treated as a corefile. If it begins with a digit,
1932 GDB will attempt to attach it as a process, and if no such process
1933 is found, will then attempt to open it as a corefile.
1935 * Changes in ARM configurations.
1937 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1938 configuration is fully multi-arch.
1940 * New native configurations
1942 ARM NetBSD arm*-*-netbsd*
1943 x86 OpenBSD i[3456]86-*-openbsd*
1944 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1945 Sparc64 running FreeBSD sparc64-*-freebsd*
1949 Sanyo XStormy16 xstormy16-elf
1951 * OBSOLETE configurations and files
1953 Configurations that have been declared obsolete in this release have
1954 been commented out. Unless there is activity to revive these
1955 configurations, the next release of GDB will have their sources
1956 permanently REMOVED.
1958 AMD 29k family via UDI a29k-amd-udi, udi29k
1959 A29K VxWorks a29k-*-vxworks
1960 AMD 29000 embedded, using EBMON a29k-none-none
1961 AMD 29000 embedded with COFF a29k-none-coff
1962 AMD 29000 embedded with a.out a29k-none-aout
1964 testsuite/gdb.hp/gdb.threads-hp/ directory
1966 * REMOVED configurations and files
1968 TI TMS320C80 tic80-*-*
1970 PowerPC Solaris powerpcle-*-solaris*
1971 PowerPC Windows NT powerpcle-*-cygwin32
1972 PowerPC Netware powerpc-*-netware*
1973 Harris/CXUX m88k m88*-harris-cxux*
1974 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1975 ns32k-utek-sysv* ns32k-utek-*
1976 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1977 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1978 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1979 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1980 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1982 * Changes to command line processing
1984 The new `--args' feature can be used to specify command-line arguments
1985 for the inferior from gdb's command line.
1987 * Changes to key bindings
1989 There is a new `operate-and-get-next' function bound to `C-o'.
1991 *** Changes in GDB 5.1.1
1993 Fix compile problem on DJGPP.
1995 Fix a problem with floating-point registers on the i386 being
1998 Fix to stop GDB crashing on .debug_str debug info.
2000 Numerous documentation fixes.
2002 Numerous testsuite fixes.
2004 *** Changes in GDB 5.1:
2006 * New native configurations
2008 Alpha FreeBSD alpha*-*-freebsd*
2009 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2010 MIPS GNU/Linux mips*-*-linux*
2011 MIPS SGI Irix 6.x mips*-sgi-irix6*
2012 ia64 AIX ia64-*-aix*
2013 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2017 Motorola 68HC11 and 68HC12 m68hc11-elf
2019 UltraSparc running GNU/Linux sparc64-*-linux*
2021 * OBSOLETE configurations and files
2023 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2024 Harris/CXUX m88k m88*-harris-cxux*
2025 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2026 ns32k-utek-sysv* ns32k-utek-*
2027 TI TMS320C80 tic80-*-*
2029 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2030 PowerPC Solaris powerpcle-*-solaris*
2031 PowerPC Windows NT powerpcle-*-cygwin32
2032 PowerPC Netware powerpc-*-netware*
2033 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2034 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2035 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2036 Apple Macintosh (MPW) host N/A
2038 stuff.c (Program to stuff files into a specially prepared space in kdb)
2039 kdb-start.c (Main loop for the standalone kernel debugger)
2041 Configurations that have been declared obsolete in this release have
2042 been commented out. Unless there is activity to revive these
2043 configurations, the next release of GDB will have their sources
2044 permanently REMOVED.
2046 * REMOVED configurations and files
2048 Altos 3068 m68*-altos-*
2049 Convex c1-*-*, c2-*-*
2051 ARM RISCix arm-*-* (as host)
2055 * GDB has been converted to ISO C.
2057 GDB's source code has been converted to ISO C. In particular, the
2058 sources are fully protoized, and rely on standard headers being
2063 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2065 * The MI enabled by default.
2067 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2068 revised and enabled by default. Packages which use GDB as a debugging
2069 engine behind a UI or another front end are encouraged to switch to
2070 using the GDB/MI interface, instead of the old annotations interface
2071 which is now deprecated.
2073 * Support for debugging Pascal programs.
2075 GDB now includes support for debugging Pascal programs. The following
2076 main features are supported:
2078 - Pascal-specific data types such as sets;
2080 - automatic recognition of Pascal sources based on file-name
2083 - Pascal-style display of data types, variables, and functions;
2085 - a Pascal expression parser.
2087 However, some important features are not yet supported.
2089 - Pascal string operations are not supported at all;
2091 - there are some problems with boolean types;
2093 - Pascal type hexadecimal constants are not supported
2094 because they conflict with the internal variables format;
2096 - support for Pascal objects and classes is not full yet;
2098 - unlike Pascal, GDB is case-sensitive for symbol names.
2100 * Changes in completion.
2102 Commands such as `shell', `run' and `set args', which pass arguments
2103 to inferior programs, now complete on file names, similar to what
2104 users expect at the shell prompt.
2106 Commands which accept locations, such as `disassemble', `print',
2107 `breakpoint', `until', etc. now complete on filenames as well as
2108 program symbols. Thus, if you type "break foob TAB", and the source
2109 files linked into the programs include `foobar.c', that file name will
2110 be one of the candidates for completion. However, file names are not
2111 considered for completion after you typed a colon that delimits a file
2112 name from a name of a function in that file, as in "break foo.c:bar".
2114 `set demangle-style' completes on available demangling styles.
2116 * New platform-independent commands:
2118 It is now possible to define a post-hook for a command as well as a
2119 hook that runs before the command. For more details, see the
2120 documentation of `hookpost' in the GDB manual.
2122 * Changes in GNU/Linux native debugging.
2124 Support for debugging multi-threaded programs has been completely
2125 revised for all platforms except m68k and sparc. You can now debug as
2126 many threads as your system allows you to have.
2128 Attach/detach is supported for multi-threaded programs.
2130 Support for SSE registers was added for x86. This doesn't work for
2131 multi-threaded programs though.
2133 * Changes in MIPS configurations.
2135 Multi-arch support is enabled for all MIPS configurations.
2137 GDB can now be built as native debugger on SGI Irix 6.x systems for
2138 debugging n32 executables. (Debugging 64-bit executables is not yet
2141 * Unified support for hardware watchpoints in all x86 configurations.
2143 Most (if not all) native x86 configurations support hardware-assisted
2144 breakpoints and watchpoints in a unified manner. This support
2145 implements debug register sharing between watchpoints, which allows to
2146 put a virtually infinite number of watchpoints on the same address,
2147 and also supports watching regions up to 16 bytes with several debug
2150 The new maintenance command `maintenance show-debug-regs' toggles
2151 debugging print-outs in functions that insert, remove, and test
2152 watchpoints and hardware breakpoints.
2154 * Changes in the DJGPP native configuration.
2156 New command ``info dos sysinfo'' displays assorted information about
2157 the CPU, OS, memory, and DPMI server.
2159 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2160 display information about segment descriptors stored in GDT, LDT, and
2163 New commands ``info dos pde'' and ``info dos pte'' display entries
2164 from Page Directory and Page Tables (for now works with CWSDPMI only).
2165 New command ``info dos address-pte'' displays the Page Table entry for
2166 a given linear address.
2168 GDB can now pass command lines longer than 126 characters to the
2169 program being debugged (requires an update to the libdbg.a library
2170 which is part of the DJGPP development kit).
2172 DWARF2 debug info is now supported.
2174 It is now possible to `step' and `next' through calls to `longjmp'.
2176 * Changes in documentation.
2178 All GDB documentation was converted to GFDL, the GNU Free
2179 Documentation License.
2181 Tracepoints-related commands are now fully documented in the GDB
2184 TUI, the Text-mode User Interface, is now documented in the manual.
2186 Tracepoints-related commands are now fully documented in the GDB
2189 The "GDB Internals" manual now has an index. It also includes
2190 documentation of `ui_out' functions, GDB coding standards, x86
2191 hardware watchpoints, and memory region attributes.
2193 * GDB's version number moved to ``version.in''
2195 The Makefile variable VERSION has been replaced by the file
2196 ``version.in''. People creating GDB distributions should update the
2197 contents of this file.
2201 GUD support is now a standard part of the EMACS distribution.
2203 *** Changes in GDB 5.0:
2205 * Improved support for debugging FP programs on x86 targets
2207 Unified and much-improved support for debugging floating-point
2208 programs on all x86 targets. In particular, ``info float'' now
2209 displays the FP registers in the same format on all x86 targets, with
2210 greater level of detail.
2212 * Improvements and bugfixes in hardware-assisted watchpoints
2214 It is now possible to watch array elements, struct members, and
2215 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2216 on x86 targets no longer erroneously trigger when the address is
2219 * Improvements in the native DJGPP version of GDB
2221 The distribution now includes all the scripts and auxiliary files
2222 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2223 machines ``out of the box''.
2225 The DJGPP version can now debug programs that use signals. It is
2226 possible to catch signals that happened in the debuggee, deliver
2227 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2228 would kill the program being debugged.) Programs that hook hardware
2229 interrupts (keyboard, timer, etc.) can also be debugged.
2231 It is now possible to debug DJGPP programs that redirect their
2232 standard handles or switch them to raw (as opposed to cooked) mode, or
2233 even close them. The command ``run < foo > bar'' works as expected,
2234 and ``info terminal'' reports useful information about the debuggee's
2235 terminal, including raw/cooked mode, redirection, etc.
2237 The DJGPP version now uses termios functions for console I/O, which
2238 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2241 DOS-style file names with drive letters are now fully supported by
2244 It is now possible to debug DJGPP programs that switch their working
2245 directory. It is also possible to rerun the debuggee any number of
2246 times without restarting GDB; thus, you can use the same setup,
2247 breakpoints, etc. for many debugging sessions.
2249 * New native configurations
2251 ARM GNU/Linux arm*-*-linux*
2252 PowerPC GNU/Linux powerpc-*-linux*
2256 Motorola MCore mcore-*-*
2257 x86 VxWorks i[3456]86-*-vxworks*
2258 PowerPC VxWorks powerpc-*-vxworks*
2259 TI TMS320C80 tic80-*-*
2261 * OBSOLETE configurations
2263 Altos 3068 m68*-altos-*
2264 Convex c1-*-*, c2-*-*
2266 ARM RISCix arm-*-* (as host)
2269 Configurations that have been declared obsolete will be commented out,
2270 but the code will be left in place. If there is no activity to revive
2271 these configurations before the next release of GDB, the sources will
2272 be permanently REMOVED.
2274 * Gould support removed
2276 Support for the Gould PowerNode and NP1 has been removed.
2278 * New features for SVR4
2280 On SVR4 native platforms (such as Solaris), if you attach to a process
2281 without first loading a symbol file, GDB will now attempt to locate and
2282 load symbols from the running process's executable file.
2284 * Many C++ enhancements
2286 C++ support has been greatly improved. Overload resolution now works properly
2287 in almost all cases. RTTI support is on the way.
2289 * Remote targets can connect to a sub-program
2291 A popen(3) style serial-device has been added. This device starts a
2292 sub-process (such as a stand-alone simulator) and then communicates
2293 with that. The sub-program to run is specified using the syntax
2294 ``|<program> <args>'' vis:
2296 (gdb) set remotedebug 1
2297 (gdb) target extended-remote |mn10300-elf-sim program-args
2299 * MIPS 64 remote protocol
2301 A long standing bug in the mips64 remote protocol where by GDB
2302 expected certain 32 bit registers (ex SR) to be transfered as 32
2303 instead of 64 bits has been fixed.
2305 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2306 added to provide backward compatibility with older versions of GDB.
2308 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2310 The command ``set remotebinarydownload'' command has been replaced by
2311 ``set remote X-packet''. Other commands in ``set remote'' family
2312 include ``set remote P-packet''.
2314 * Breakpoint commands accept ranges.
2316 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2317 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2318 ``tracepoint passcount'' also accepts a range of tracepoints.
2320 * ``apropos'' command added.
2322 The ``apropos'' command searches through command names and
2323 documentation strings, printing out matches, making it much easier to
2324 try to find a command that does what you are looking for.
2328 A new machine oriented interface (MI) has been added to GDB. This
2329 interface is designed for debug environments running GDB as a separate
2330 process. This is part of the long term libGDB project. See the
2331 "GDB/MI" chapter of the GDB manual for further information. It can be
2332 enabled by configuring with:
2334 .../configure --enable-gdbmi
2336 *** Changes in GDB-4.18:
2338 * New native configurations
2340 HP-UX 10.20 hppa*-*-hpux10.20
2341 HP-UX 11.x hppa*-*-hpux11.0*
2342 M68K GNU/Linux m68*-*-linux*
2346 Fujitsu FR30 fr30-*-elf*
2347 Intel StrongARM strongarm-*-*
2348 Mitsubishi D30V d30v-*-*
2350 * OBSOLETE configurations
2352 Gould PowerNode, NP1 np1-*-*, pn-*-*
2354 Configurations that have been declared obsolete will be commented out,
2355 but the code will be left in place. If there is no activity to revive
2356 these configurations before the next release of GDB, the sources will
2357 be permanently REMOVED.
2361 As a compatibility experiment, GDB's source files buildsym.h and
2362 buildsym.c have been converted to pure standard C, no longer
2363 containing any K&R compatibility code. We believe that all systems in
2364 use today either come with a standard C compiler, or have a GCC port
2365 available. If this is not true, please report the affected
2366 configuration to bug-gdb@gnu.org immediately. See the README file for
2367 information about getting a standard C compiler if you don't have one
2372 GDB now uses readline 2.2.
2374 * set extension-language
2376 You can now control the mapping between filename extensions and source
2377 languages by using the `set extension-language' command. For instance,
2378 you can ask GDB to treat .c files as C++ by saying
2379 set extension-language .c c++
2380 The command `info extensions' lists all of the recognized extensions
2381 and their associated languages.
2383 * Setting processor type for PowerPC and RS/6000
2385 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2386 you can use the `set processor' command to specify what variant of the
2387 PowerPC family you are debugging. The command
2391 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2392 following PowerPC and RS6000 variants:
2394 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2395 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2397 403GC IBM PowerPC 403GC
2398 505 Motorola PowerPC 505
2399 860 Motorola PowerPC 860 or 850
2400 601 Motorola PowerPC 601
2401 602 Motorola PowerPC 602
2402 603 Motorola/IBM PowerPC 603 or 603e
2403 604 Motorola PowerPC 604 or 604e
2404 750 Motorola/IBM PowerPC 750 or 750
2406 At the moment, this command just tells GDB what to name the
2407 special-purpose processor registers. Since almost all the affected
2408 registers are inaccessible to user-level programs, this command is
2409 only useful for remote debugging in its present form.
2413 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2414 more extensive support for HP-UX. Added features include shared
2415 library support, kernel threads and hardware watchpoints for 11.00,
2416 support for HP's ANSI C and C++ compilers, and a compatibility mode
2417 for xdb and dbx commands.
2421 HP's donation includes the new concept of catchpoints, which is a
2422 generalization of the old catch command. On HP-UX, it is now possible
2423 to catch exec, fork, and vfork, as well as library loading.
2425 This means that the existing catch command has changed; its first
2426 argument now specifies the type of catch to be set up. See the
2427 output of "help catch" for a list of catchpoint types.
2429 * Debugging across forks
2431 On HP-UX, you can choose which process to debug when a fork() happens
2436 HP has donated a curses-based terminal user interface (TUI). To get
2437 it, build with --enable-tui. Although this can be enabled for any
2438 configuration, at present it only works for native HP debugging.
2440 * GDB remote protocol additions
2442 A new protocol packet 'X' that writes binary data is now available.
2443 Default behavior is to try 'X', then drop back to 'M' if the stub
2444 fails to respond. The settable variable `remotebinarydownload'
2445 allows explicit control over the use of 'X'.
2447 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2448 full 64-bit address. The command
2450 set remoteaddresssize 32
2452 can be used to revert to the old behaviour. For existing remote stubs
2453 the change should not be noticed, as the additional address information
2456 In order to assist in debugging stubs, you may use the maintenance
2457 command `packet' to send any text string to the stub. For instance,
2459 maint packet heythere
2461 sends the packet "$heythere#<checksum>". Note that it is very easy to
2462 disrupt a debugging session by sending the wrong packet at the wrong
2465 The compare-sections command allows you to compare section data on the
2466 target to what is in the executable file without uploading or
2467 downloading, by comparing CRC checksums.
2469 * Tracing can collect general expressions
2471 You may now collect general expressions at tracepoints. This requires
2472 further additions to the target-side stub; see tracepoint.c and
2473 doc/agentexpr.texi for further details.
2475 * mask-address variable for Mips
2477 For Mips targets, you may control the zeroing of the upper 32 bits of
2478 a 64-bit address by entering `set mask-address on'. This is mainly
2479 of interest to users of embedded R4xxx and R5xxx processors.
2481 * Higher serial baud rates
2483 GDB's serial code now allows you to specify baud rates 57600, 115200,
2484 230400, and 460800 baud. (Note that your host system may not be able
2485 to achieve all of these rates.)
2489 The i960 configuration now includes an initial implementation of a
2490 builtin simulator, contributed by Jim Wilson.
2493 *** Changes in GDB-4.17:
2495 * New native configurations
2497 Alpha GNU/Linux alpha*-*-linux*
2498 Unixware 2.x i[3456]86-unixware2*
2499 Irix 6.x mips*-sgi-irix6*
2500 PowerPC GNU/Linux powerpc-*-linux*
2501 PowerPC Solaris powerpcle-*-solaris*
2502 Sparc GNU/Linux sparc-*-linux*
2503 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2507 Argonaut Risc Chip (ARC) arc-*-*
2508 Hitachi H8/300S h8300*-*-*
2509 Matsushita MN10200 w/simulator mn10200-*-*
2510 Matsushita MN10300 w/simulator mn10300-*-*
2511 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2512 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2513 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2514 Mitsubishi D10V w/simulator d10v-*-*
2515 Mitsubishi M32R/D w/simulator m32r-*-elf*
2516 Tsqware Sparclet sparclet-*-*
2517 NEC V850 w/simulator v850-*-*
2519 * New debugging protocols
2521 ARM with RDI protocol arm*-*-*
2522 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2523 DDB and LSI variants of PMON protocol mips*-*-*
2524 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2525 PowerPC with SDS protocol powerpc{,le}-*-eabi
2526 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2530 All configurations can now understand and use the DWARF 2 debugging
2531 format. The choice is automatic, if the symbol file contains DWARF 2
2536 GDB now includes basic Java language support. This support is
2537 only useful with Java compilers that produce native machine code.
2539 * solib-absolute-prefix and solib-search-path
2541 For SunOS and SVR4 shared libraries, you may now set the prefix for
2542 loading absolute shared library symbol files, and the search path for
2543 locating non-absolute shared library symbol files.
2545 * Live range splitting
2547 GDB can now effectively debug code for which GCC has performed live
2548 range splitting as part of its optimization. See gdb/doc/LRS for
2549 more details on the expected format of the stabs information.
2553 GDB's support for the GNU Hurd, including thread debugging, has been
2554 updated to work with current versions of the Hurd.
2558 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2559 instruction set. ARM GDB automatically detects when Thumb
2560 instructions are in use, and adjusts disassembly and backtracing
2565 GDB's MIPS target configurations now handle the MIP16 16-bit
2570 GDB now includes support for overlays; if an executable has been
2571 linked such that multiple sections are based at the same address, GDB
2572 will decide which section to use for symbolic info. You can choose to
2573 control the decision manually, using overlay commands, or implement
2574 additional target-side support and use "overlay load-target" to bring
2575 in the overlay mapping. Do "help overlay" for more detail.
2579 The command "info symbol <address>" displays information about
2580 the symbol at the specified address.
2584 The standard remote protocol now includes an extension that allows
2585 asynchronous collection and display of trace data. This requires
2586 extensive support in the target-side debugging stub. Tracing mode
2587 includes a new interaction mode in GDB and new commands: see the
2588 file tracepoint.c for more details.
2592 Configurations for embedded MIPS now include a simulator contributed
2593 by Cygnus Solutions. The simulator supports the instruction sets
2594 of most MIPS variants.
2598 Sparc configurations may now include the ERC32 simulator contributed
2599 by the European Space Agency. The simulator is not built into
2600 Sparc targets by default; configure with --enable-sim to include it.
2604 For target configurations that may include multiple variants of a
2605 basic architecture (such as MIPS and SH), you may now set the
2606 architecture explicitly. "set arch" sets, "info arch" lists
2607 the possible architectures.
2609 *** Changes in GDB-4.16:
2611 * New native configurations
2613 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2614 M68K NetBSD m68k-*-netbsd*
2615 PowerPC AIX 4.x powerpc-*-aix*
2616 PowerPC MacOS powerpc-*-macos*
2617 PowerPC Windows NT powerpcle-*-cygwin32
2618 RS/6000 AIX 4.x rs6000-*-aix4*
2622 ARM with RDP protocol arm-*-*
2623 I960 with MON960 i960-*-coff
2624 MIPS VxWorks mips*-*-vxworks*
2625 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2626 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2628 Matra Sparclet sparclet-*-*
2632 The powerpc-eabi configuration now includes the PSIM simulator,
2633 contributed by Andrew Cagney, with assistance from Mike Meissner.
2634 PSIM is a very elaborate model of the PowerPC, including not only
2635 basic instruction set execution, but also details of execution unit
2636 performance and I/O hardware. See sim/ppc/README for more details.
2640 GDB now works with Solaris 2.5.
2642 * Windows 95/NT native
2644 GDB will now work as a native debugger on Windows 95 and Windows NT.
2645 To build it from source, you must use the "gnu-win32" environment,
2646 which uses a DLL to emulate enough of Unix to run the GNU tools.
2647 Further information, binaries, and sources are available at
2648 ftp.cygnus.com, under pub/gnu-win32.
2650 * dont-repeat command
2652 If a user-defined command includes the command `dont-repeat', then the
2653 command will not be repeated if the user just types return. This is
2654 useful if the command is time-consuming to run, so that accidental
2655 extra keystrokes don't run the same command many times.
2657 * Send break instead of ^C
2659 The standard remote protocol now includes an option to send a break
2660 rather than a ^C to the target in order to interrupt it. By default,
2661 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2663 * Remote protocol timeout
2665 The standard remote protocol includes a new variable `remotetimeout'
2666 that allows you to set the number of seconds before GDB gives up trying
2667 to read from the target. The default value is 2.
2669 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2671 By default GDB will automatically keep track of objects as they are
2672 loaded and unloaded by the dynamic linker. By using the command `set
2673 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2674 when shared library events occur, thus allowing you to set breakpoints
2675 in shared libraries which are explicitly loaded by the inferior.
2677 Note this feature does not work on hpux8. On hpux9 you must link
2678 /usr/lib/end.o into your program. This feature should work
2679 automatically on hpux10.
2681 * Irix 5.x hardware watchpoint support
2683 Irix 5 configurations now support the use of hardware watchpoints.
2685 * Mips protocol "SYN garbage limit"
2687 When debugging a Mips target using the `target mips' protocol, you
2688 may set the number of characters that GDB will ignore by setting
2689 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2690 every character. The default value is 1050.
2692 * Recording and replaying remote debug sessions
2694 If you set `remotelogfile' to the name of a file, gdb will write to it
2695 a recording of a remote debug session. This recording may then be
2696 replayed back to gdb using "gdbreplay". See gdbserver/README for
2697 details. This is useful when you have a problem with GDB while doing
2698 remote debugging; you can make a recording of the session and send it
2699 to someone else, who can then recreate the problem.
2701 * Speedups for remote debugging
2703 GDB includes speedups for downloading and stepping MIPS systems using
2704 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2705 and more efficient S-record downloading.
2707 * Memory use reductions and statistics collection
2709 GDB now uses less memory and reports statistics about memory usage.
2710 Try the `maint print statistics' command, for example.
2712 *** Changes in GDB-4.15:
2714 * Psymtabs for XCOFF
2716 The symbol reader for AIX GDB now uses partial symbol tables. This
2717 can greatly improve startup time, especially for large executables.
2719 * Remote targets use caching
2721 Remote targets now use a data cache to speed up communication with the
2722 remote side. The data cache could lead to incorrect results because
2723 it doesn't know about volatile variables, thus making it impossible to
2724 debug targets which use memory mapped I/O devices. `set remotecache
2725 off' turns the the data cache off.
2727 * Remote targets may have threads
2729 The standard remote protocol now includes support for multiple threads
2730 in the target system, using new protocol commands 'H' and 'T'. See
2731 gdb/remote.c for details.
2735 If GDB is configured with `--enable-netrom', then it will include
2736 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2737 acts as though it is a bank of ROM on the target board, but you can
2738 write into it over the network. GDB's support consists only of
2739 support for fast loading into the emulated ROM; to debug, you must use
2740 another protocol, such as standard remote protocol. The usual
2741 sequence is something like
2743 target nrom <netrom-hostname>
2745 target remote <netrom-hostname>:1235
2749 GDB now includes support for the Apple Macintosh, as a host only. It
2750 may be run as either an MPW tool or as a standalone application, and
2751 it can debug through the serial port. All the usual GDB commands are
2752 available, but to the target command, you must supply "serial" as the
2753 device type instead of "/dev/ttyXX". See mpw-README in the main
2754 directory for more information on how to build. The MPW configuration
2755 scripts */mpw-config.in support only a few targets, and only the
2756 mips-idt-ecoff target has been tested.
2760 GDB configuration now uses autoconf. This is not user-visible,
2761 but does simplify configuration and building.
2765 GDB now supports hpux10.
2767 *** Changes in GDB-4.14:
2769 * New native configurations
2771 x86 FreeBSD i[345]86-*-freebsd
2772 x86 NetBSD i[345]86-*-netbsd
2773 NS32k NetBSD ns32k-*-netbsd
2774 Sparc NetBSD sparc-*-netbsd
2778 A29K VxWorks a29k-*-vxworks
2779 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2780 CPU32 EST-300 emulator m68*-*-est*
2781 PowerPC ELF powerpc-*-elf
2784 * Alpha OSF/1 support for procfs
2786 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2787 possible to attach to running processes. As the mounting of the /proc
2788 filesystem is optional on the Alpha, GDB automatically determines
2789 the availability of /proc during startup. This can lead to problems
2790 if /proc is unmounted after GDB has been started.
2792 * Arguments to user-defined commands
2794 User commands may accept up to 10 arguments separated by whitespace.
2795 Arguments are accessed within the user command via $arg0..$arg9. A
2798 print $arg0 + $arg1 + $arg2
2800 To execute the command use:
2803 Defines the command "adder" which prints the sum of its three arguments.
2804 Note the arguments are text substitutions, so they may reference variables,
2805 use complex expressions, or even perform inferior function calls.
2807 * New `if' and `while' commands
2809 This makes it possible to write more sophisticated user-defined
2810 commands. Both commands take a single argument, which is the
2811 expression to evaluate, and must be followed by the commands to
2812 execute, one per line, if the expression is nonzero, the list being
2813 terminated by the word `end'. The `if' command list may include an
2814 `else' word, which causes the following commands to be executed only
2815 if the expression is zero.
2817 * Fortran source language mode
2819 GDB now includes partial support for Fortran 77. It will recognize
2820 Fortran programs and can evaluate a subset of Fortran expressions, but
2821 variables and functions may not be handled correctly. GDB will work
2822 with G77, but does not yet know much about symbols emitted by other
2825 * Better HPUX support
2827 Most debugging facilities now work on dynamic executables for HPPAs
2828 running hpux9 or later. You can attach to running dynamically linked
2829 processes, but by default the dynamic libraries will be read-only, so
2830 for instance you won't be able to put breakpoints in them. To change
2831 that behavior do the following before running the program:
2837 This will cause the libraries to be mapped private and read-write.
2838 To revert to the normal behavior, do this:
2844 You cannot set breakpoints or examine data in the library until after
2845 the library is loaded if the function/data symbols do not have
2848 GDB can now also read debug symbols produced by the HP C compiler on
2849 HPPAs (sorry, no C++, Fortran or 68k support).
2851 * Target byte order now dynamically selectable
2853 You can choose which byte order to use with a target system, via the
2854 commands "set endian big" and "set endian little", and you can see the
2855 current setting by using "show endian". You can also give the command
2856 "set endian auto", in which case GDB will use the byte order
2857 associated with the executable. Currently, only embedded MIPS
2858 configurations support dynamic selection of target byte order.
2860 * New DOS host serial code
2862 This version uses DPMI interrupts to handle buffered I/O, so you
2863 no longer need to run asynctsr when debugging boards connected to
2866 *** Changes in GDB-4.13:
2868 * New "complete" command
2870 This lists all the possible completions for the rest of the line, if it
2871 were to be given as a command itself. This is intended for use by emacs.
2873 * Trailing space optional in prompt
2875 "set prompt" no longer adds a space for you after the prompt you set. This
2876 allows you to set a prompt which ends in a space or one that does not.
2878 * Breakpoint hit counts
2880 "info break" now displays a count of the number of times the breakpoint
2881 has been hit. This is especially useful in conjunction with "ignore"; you
2882 can ignore a large number of breakpoint hits, look at the breakpoint info
2883 to see how many times the breakpoint was hit, then run again, ignoring one
2884 less than that number, and this will get you quickly to the last hit of
2887 * Ability to stop printing at NULL character
2889 "set print null-stop" will cause GDB to stop printing the characters of
2890 an array when the first NULL is encountered. This is useful when large
2891 arrays actually contain only short strings.
2893 * Shared library breakpoints
2895 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2896 breakpoints in shared libraries before the executable is run.
2898 * Hardware watchpoints
2900 There is a new hardware breakpoint for the watch command for sparclite
2901 targets. See gdb/sparclite/hw_breakpoint.note.
2903 Hardware watchpoints are also now supported under GNU/Linux.
2907 Annotations have been added. These are for use with graphical interfaces,
2908 and are still experimental. Currently only gdba.el uses these.
2910 * Improved Irix 5 support
2912 GDB now works properly with Irix 5.2.
2914 * Improved HPPA support
2916 GDB now works properly with the latest GCC and GAS.
2918 * New native configurations
2920 Sequent PTX4 i[34]86-sequent-ptx4
2921 HPPA running OSF/1 hppa*-*-osf*
2922 Atari TT running SVR4 m68*-*-sysv4*
2923 RS/6000 LynxOS rs6000-*-lynxos*
2927 OS/9000 i[34]86-*-os9k
2928 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2931 * Hitachi SH7000 and E7000-PC ICE support
2933 There is now support for communicating with the Hitachi E7000-PC ICE.
2934 This is available automatically when GDB is configured for the SH.
2938 As usual, a variety of small fixes and improvements, both generic
2939 and configuration-specific. See the ChangeLog for more detail.
2941 *** Changes in GDB-4.12:
2943 * Irix 5 is now supported
2947 GDB-4.12 on the HPPA has a number of changes which make it unable
2948 to debug the output from the currently released versions of GCC and
2949 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2950 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2951 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2954 *** Changes in GDB-4.11:
2956 * User visible changes:
2960 The "set remotedebug" option is now consistent between the mips remote
2961 target, remote targets using the gdb-specific protocol, UDI (AMD's
2962 debug protocol for the 29k) and the 88k bug monitor. It is now an
2963 integer specifying a debug level (normally 0 or 1, but 2 means more
2964 debugging info for the mips target).
2966 * DEC Alpha native support
2968 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2969 debug info, but GDB works fairly well with the DEC compiler and should
2970 work with a future GCC release. See the README file for a few
2971 Alpha-specific notes.
2973 * Preliminary thread implementation
2975 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2977 * LynxOS native and target support for 386
2979 This release has been hosted on LynxOS 2.2, and also can be configured
2980 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
2983 * Improvements in C++ mangling/demangling.
2985 This release has much better g++ debugging, specifically in name
2986 mangling/demangling, virtual function calls, print virtual table,
2987 call methods, ...etc.
2989 *** Changes in GDB-4.10:
2991 * User visible changes:
2993 Remote debugging using the GDB-specific (`target remote') protocol now
2994 supports the `load' command. This is only useful if you have some
2995 other way of getting the stub to the target system, and you can put it
2996 somewhere in memory where it won't get clobbered by the download.
2998 Filename completion now works.
3000 When run under emacs mode, the "info line" command now causes the
3001 arrow to point to the line specified. Also, "info line" prints
3002 addresses in symbolic form (as well as hex).
3004 All vxworks based targets now support a user settable option, called
3005 vxworks-timeout. This option represents the number of seconds gdb
3006 should wait for responses to rpc's. You might want to use this if
3007 your vxworks target is, perhaps, a slow software simulator or happens
3008 to be on the far side of a thin network line.
3012 This release contains support for using a DEC alpha as a GDB host for
3013 cross debugging. Native alpha debugging is not supported yet.
3016 *** Changes in GDB-4.9:
3020 This is the first GDB release which is accompanied by a matching testsuite.
3021 The testsuite requires installation of dejagnu, which should be available
3022 via ftp from most sites that carry GNU software.
3026 'Cfront' style demangling has had its name changed to 'ARM' style, to
3027 emphasize that it was written from the specifications in the C++ Annotated
3028 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3029 disclaimers, it still generated too much confusion with users attempting to
3030 use gdb with AT&T cfront.
3034 GDB now uses a standard remote interface to a simulator library.
3035 So far, the library contains simulators for the Zilog Z8001/2, the
3036 Hitachi H8/300, H8/500 and Super-H.
3038 * New targets supported
3040 H8/300 simulator h8300-hitachi-hms or h8300hms
3041 H8/500 simulator h8500-hitachi-hms or h8500hms
3042 SH simulator sh-hitachi-hms or sh
3043 Z8000 simulator z8k-zilog-none or z8ksim
3044 IDT MIPS board over serial line mips-idt-ecoff
3046 Cross-debugging to GO32 targets is supported. It requires a custom
3047 version of the i386-stub.c module which is integrated with the
3048 GO32 memory extender.
3050 * New remote protocols
3052 MIPS remote debugging protocol.
3054 * New source languages supported
3056 This version includes preliminary support for Chill, a Pascal like language
3057 used by telecommunications companies. Chill support is also being integrated
3058 into the GNU compiler, but we don't know when it will be publically available.
3061 *** Changes in GDB-4.8:
3063 * HP Precision Architecture supported
3065 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3066 version of this support was available as a set of patches from the
3067 University of Utah. GDB does not support debugging of programs
3068 compiled with the HP compiler, because HP will not document their file
3069 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3070 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3072 Many problems in the preliminary version have been fixed.
3074 * Faster and better demangling
3076 We have improved template demangling and fixed numerous bugs in the GNU style
3077 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3078 character types (wchar_t) are now supported. Demangling of each symbol is now
3079 only done once, and is cached when the symbol table for a file is read in.
3080 This results in a small increase in memory usage for C programs, a moderate
3081 increase in memory usage for C++ programs, and a fantastic speedup in
3084 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3085 from the specifications in the Annotated Reference Manual, which AT&T's
3086 compiler does not actually implement.
3088 * G++ multiple inheritance compiler problem
3090 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3091 inheritance lattices was reworked to properly discover ambiguities. We
3092 recently found an example which causes this new algorithm to fail in a
3093 very subtle way, producing bad debug information for those classes.
3094 The file 'gcc.patch' (in this directory) can be applied to gcc to
3095 circumvent the problem. A future GCC release will contain a complete
3098 The previous G++ debug info problem (mentioned below for the gdb-4.7
3099 release) is fixed in gcc version 2.3.2.
3101 * Improved configure script
3103 The `configure' script will now attempt to guess your system type if
3104 you don't supply a host system type. The old scheme of supplying a
3105 host system triplet is preferable over using this. All the magic is
3106 done in the new `config.guess' script. Examine it for details.
3108 We have also brought our configure script much more in line with the FSF's
3109 version. It now supports the --with-xxx options. In particular,
3110 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3111 The resulting GDB will not be able to read arbitrary object file formats --
3112 only the format ``expected'' to be used on the configured target system.
3113 We hope to make this the default in a future release.
3115 * Documentation improvements
3117 There's new internal documentation on how to modify GDB, and how to
3118 produce clean changes to the code. We implore people to read it
3119 before submitting changes.
3121 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3122 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3123 `info' files are also provided. To build `info' files from scratch,
3124 you will need the latest `makeinfo' release, which will be available in
3125 a future texinfo-X.Y release.
3127 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3128 We're not sure exactly which versions have this problem, but it has
3129 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3130 or better. If that isn't possible, there is a patch in
3131 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3132 around this problem.
3136 GDB now supports array constants that can be used in expressions typed in by
3137 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3138 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3141 The new directory `gdb/sparclite' contains a program that demonstrates
3142 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3144 * New native hosts supported
3146 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3147 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3149 * New targets supported
3151 AMD 29k family via UDI a29k-amd-udi or udi29k
3153 * New file formats supported
3155 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3156 HPUX core files, and SCO 3.2v2 core files.
3160 Attaching to processes now works again; thanks for the many bug reports.
3162 We have also stomped on a bunch of core dumps caused by
3163 printf_filtered("%s") problems.
3165 We eliminated a copyright problem on the rpc and ptrace header files
3166 for VxWorks, which was discovered at the last minute during the 4.7
3167 release. You should now be able to build a VxWorks GDB.
3169 You can now interrupt gdb while an attached process is running. This
3170 will cause the attached process to stop, and give control back to GDB.
3172 We fixed problems caused by using too many file descriptors
3173 for reading symbols from object files and libraries. This was
3174 especially a problem for programs that used many (~100) shared
3177 The `step' command now only enters a subroutine if there is line number
3178 information for the subroutine. Otherwise it acts like the `next'
3179 command. Previously, `step' would enter subroutines if there was
3180 any debugging information about the routine. This avoids problems
3181 when using `cc -g1' on MIPS machines.
3183 * Internal improvements
3185 GDB's internal interfaces have been improved to make it easier to support
3186 debugging of multiple languages in the future.
3188 GDB now uses a common structure for symbol information internally.
3189 Minimal symbols (derived from linkage symbols in object files), partial
3190 symbols (from a quick scan of debug information), and full symbols
3191 contain a common subset of information, making it easier to write
3192 shared code that handles any of them.
3194 * New command line options
3196 We now accept --silent as an alias for --quiet.
3200 The memory-mapped-malloc library is now licensed under the GNU Library
3201 General Public License.
3203 *** Changes in GDB-4.7:
3205 * Host/native/target split
3207 GDB has had some major internal surgery to untangle the support for
3208 hosts and remote targets. Now, when you configure GDB for a remote
3209 target, it will no longer load in all of the support for debugging
3210 local programs on the host. When fully completed and tested, this will
3211 ensure that arbitrary host/target combinations are possible.
3213 The primary conceptual shift is to separate the non-portable code in
3214 GDB into three categories. Host specific code is required any time GDB
3215 is compiled on that host, regardless of the target. Target specific
3216 code relates to the peculiarities of the target, but can be compiled on
3217 any host. Native specific code is everything else: it can only be
3218 built when the host and target are the same system. Child process
3219 handling and core file support are two common `native' examples.
3221 GDB's use of /proc for controlling Unix child processes is now cleaner.
3222 It has been split out into a single module under the `target_ops' vector,
3223 plus two native-dependent functions for each system that uses /proc.
3225 * New hosts supported
3227 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3228 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3229 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3231 * New targets supported
3233 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3234 68030 and CPU32 m68030-*-*, m68332-*-*
3236 * New native hosts supported
3238 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3239 (386bsd is not well tested yet)
3240 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3242 * New file formats supported
3244 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3245 supports reading of `a.out.adobe' object files, which are an a.out
3246 format extended with minimal information about multiple sections.
3250 `show copying' is the same as the old `info copying'.
3251 `show warranty' is the same as `info warrantee'.
3252 These were renamed for consistency. The old commands continue to work.
3254 `info handle' is a new alias for `info signals'.
3256 You can now define pre-command hooks, which attach arbitrary command
3257 scripts to any command. The commands in the hook will be executed
3258 prior to the user's command. You can also create a hook which will be
3259 executed whenever the program stops. See gdb.texinfo.
3263 We now deal with Cfront style name mangling, and can even extract type
3264 info from mangled symbols. GDB can automatically figure out which
3265 symbol mangling style your C++ compiler uses.
3267 Calling of methods and virtual functions has been improved as well.
3271 The crash that occured when debugging Sun Ansi-C compiled binaries is
3272 fixed. This was due to mishandling of the extra N_SO stabs output
3275 We also finally got Ultrix 4.2 running in house, and fixed core file
3276 support, with help from a dozen people on the net.
3278 John M. Farrell discovered that the reason that single-stepping was so
3279 slow on all of the Mips based platforms (primarily SGI and DEC) was
3280 that we were trying to demangle and lookup a symbol used for internal
3281 purposes on every instruction that was being stepped through. Changing
3282 the name of that symbol so that it couldn't be mistaken for a C++
3283 mangled symbol sped things up a great deal.
3285 Rich Pixley sped up symbol lookups in general by getting much smarter
3286 about when C++ symbol mangling is necessary. This should make symbol
3287 completion (TAB on the command line) much faster. It's not as fast as
3288 we'd like, but it's significantly faster than gdb-4.6.
3292 A new user controllable variable 'call_scratch_address' can
3293 specify the location of a scratch area to be used when GDB
3294 calls a function in the target. This is necessary because the
3295 usual method of putting the scratch area on the stack does not work
3296 in systems that have separate instruction and data spaces.
3298 We integrated changes to support the 29k UDI (Universal Debugger
3299 Interface), but discovered at the last minute that we didn't have all
3300 of the appropriate copyright paperwork. We are working with AMD to
3301 resolve this, and hope to have it available soon.
3305 We have sped up the remote serial line protocol, especially for targets
3306 with lots of registers. It now supports a new `expedited status' ('T')
3307 message which can be used in place of the existing 'S' status message.
3308 This allows the remote stub to send only the registers that GDB
3309 needs to make a quick decision about single-stepping or conditional
3310 breakpoints, eliminating the need to fetch the entire register set for
3311 each instruction being stepped through.
3313 The GDB remote serial protocol now implements a write-through cache for
3314 registers, only re-reading the registers if the target has run.
3316 There is also a new remote serial stub for SPARC processors. You can
3317 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3318 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3319 processor with a serial port.
3323 Configure.in files have become much easier to read and modify. A new
3324 `table driven' format makes it more obvious what configurations are
3325 supported, and what files each one uses.
3329 There is a new opcodes library which will eventually contain all of the
3330 disassembly routines and opcode tables. At present, it only contains
3331 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3332 disassembler (binutils/objdump) to share these routines.
3334 The libiberty library is now copylefted under the GNU Library General
3335 Public License. This allows more liberal use, and was done so libg++
3336 can use it. This makes no difference to GDB, since the Library License
3337 grants all the rights from the General Public License.
3341 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3342 reference to the stabs symbol info used by the debugger. It is (as far
3343 as we know) the only published document on this fascinating topic. We
3344 encourage you to read it, compare it to the stabs information on your
3345 system, and send improvements on the document in general (to
3346 bug-gdb@prep.ai.mit.edu).
3348 And, of course, many bugs have been fixed.
3351 *** Changes in GDB-4.6:
3353 * Better support for C++ function names
3355 GDB now accepts as input the "demangled form" of C++ overloaded function
3356 names and member function names, and can do command completion on such names
3357 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3358 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3359 Make use of command completion, it is your friend.
3361 GDB also now accepts a variety of C++ mangled symbol formats. They are
3362 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3363 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3364 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3365 for the list of formats.
3367 * G++ symbol mangling problem
3369 Recent versions of gcc have a bug in how they emit debugging information for
3370 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3371 directory) can be applied to gcc to fix the problem. Alternatively, if you
3372 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3373 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3374 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3377 * New 'maintenance' command
3379 All of the commands related to hacking GDB internals have been moved out of
3380 the main command set, and now live behind the 'maintenance' command. This
3381 can also be abbreviated as 'mt'. The following changes were made:
3383 dump-me -> maintenance dump-me
3384 info all-breakpoints -> maintenance info breakpoints
3385 printmsyms -> maintenance print msyms
3386 printobjfiles -> maintenance print objfiles
3387 printpsyms -> maintenance print psymbols
3388 printsyms -> maintenance print symbols
3390 The following commands are new:
3392 maintenance demangle Call internal GDB demangler routine to
3393 demangle a C++ link name and prints the result.
3394 maintenance print type Print a type chain for a given symbol
3396 * Change to .gdbinit file processing
3398 We now read the $HOME/.gdbinit file before processing the argv arguments
3399 (e.g. reading symbol files or core files). This allows global parameters to
3400 be set, which will apply during the symbol reading. The ./.gdbinit is still
3401 read after argv processing.
3403 * New hosts supported
3405 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3407 GNU/Linux support i386-unknown-linux or linux
3409 We are also including code to support the HP/PA running BSD and HPUX. This
3410 is almost guaranteed not to work, as we didn't have time to test or build it
3411 for this release. We are including it so that the more adventurous (or
3412 masochistic) of you can play with it. We also had major problems with the
3413 fact that the compiler that we got from HP doesn't support the -g option.
3416 * New targets supported
3418 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3420 * More smarts about finding #include files
3422 GDB now remembers the compilation directory for all include files, and for
3423 all files from which C is generated (like yacc and lex sources). This
3424 greatly improves GDB's ability to find yacc/lex sources, and include files,
3425 especially if you are debugging your program from a directory different from
3426 the one that contains your sources.
3428 We also fixed a bug which caused difficulty with listing and setting
3429 breakpoints in include files which contain C code. (In the past, you had to
3430 try twice in order to list an include file that you hadn't looked at before.)
3432 * Interesting infernals change
3434 GDB now deals with arbitrary numbers of sections, where the symbols for each
3435 section must be relocated relative to that section's landing place in the
3436 target's address space. This work was needed to support ELF with embedded
3437 stabs used by Solaris-2.0.
3439 * Bug fixes (of course!)
3441 There have been loads of fixes for the following things:
3442 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3443 i960, stabs, DOS(GO32), procfs, etc...
3445 See the ChangeLog for details.
3447 *** Changes in GDB-4.5:
3449 * New machines supported (host and target)
3451 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3453 SGI Irix-4.x mips-sgi-irix4 or iris4
3455 * New malloc package
3457 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3458 Mmalloc is capable of handling mutiple heaps of memory. It is also
3459 capable of saving a heap to a file, and then mapping it back in later.
3460 This can be used to greatly speedup the startup of GDB by using a
3461 pre-parsed symbol table which lives in a mmalloc managed heap. For
3462 more details, please read mmalloc/mmalloc.texi.
3466 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3467 'help info proc' for details.
3469 * MIPS ecoff symbol table format
3471 The code that reads MIPS symbol table format is now supported on all hosts.
3472 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3475 * File name changes for MS-DOS
3477 Many files in the config directories have been renamed to make it easier to
3478 support GDB on MS-DOSe systems (which have very restrictive file name
3479 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3480 environment) is close to working but has some remaining problems. Note
3481 that debugging of DOS programs is not supported, due to limitations
3482 in the ``operating system'', but it can be used to host cross-debugging.
3484 * Cross byte order fixes
3486 Many fixes have been made to support cross debugging of Sparc and MIPS
3487 targets from hosts whose byte order differs.
3489 * New -mapped and -readnow options
3491 If memory-mapped files are available on your system through the 'mmap'
3492 system call, you can use the -mapped option on the `file' or
3493 `symbol-file' commands to cause GDB to write the symbols from your
3494 program into a reusable file. If the program you are debugging is
3495 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3496 Future GDB debugging sessions will notice the presence of this file,
3497 and will quickly map in symbol information from it, rather than reading
3498 the symbol table from the executable program. Using the '-mapped'
3499 option in a GDB `file' or `symbol-file' command has the same effect as
3500 starting GDB with the '-mapped' command-line option.
3502 You can cause GDB to read the entire symbol table immediately by using
3503 the '-readnow' option with any of the commands that load symbol table
3504 information (or on the GDB command line). This makes the command
3505 slower, but makes future operations faster.
3507 The -mapped and -readnow options are typically combined in order to
3508 build a `fred.syms' file that contains complete symbol information.
3509 A simple GDB invocation to do nothing but build a `.syms' file for future
3512 gdb -batch -nx -mapped -readnow programname
3514 The `.syms' file is specific to the host machine on which GDB is run.
3515 It holds an exact image of GDB's internal symbol table. It cannot be
3516 shared across multiple host platforms.
3518 * longjmp() handling
3520 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3521 siglongjmp() without losing control. This feature has not yet been ported to
3522 all systems. It currently works on many 386 platforms, all MIPS-based
3523 platforms (SGI, DECstation, etc), and Sun3/4.
3527 Preliminary work has been put in to support the new Solaris OS from Sun. At
3528 this time, it can control and debug processes, but it is not capable of
3533 As always, many many bug fixes. The major areas were with g++, and mipsread.
3534 People using the MIPS-based platforms should experience fewer mysterious
3535 crashes and trashed symbol tables.
3537 *** Changes in GDB-4.4:
3539 * New machines supported (host and target)
3541 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3543 BSD Reno on Vax vax-dec-bsd
3544 Ultrix on Vax vax-dec-ultrix
3546 * New machines supported (target)
3548 AMD 29000 embedded, using EBMON a29k-none-none
3552 GDB continues to improve its handling of C++. `References' work better.
3553 The demangler has also been improved, and now deals with symbols mangled as
3554 per the Annotated C++ Reference Guide.
3556 GDB also now handles `stabs' symbol information embedded in MIPS
3557 `ecoff' symbol tables. Since the ecoff format was not easily
3558 extensible to handle new languages such as C++, this appeared to be a
3559 good way to put C++ debugging info into MIPS binaries. This option
3560 will be supported in the GNU C compiler, version 2, when it is
3563 * New features for SVR4
3565 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3566 shared libraries. Debugging dynamically linked programs should present
3567 only minor differences from debugging statically linked programs.
3569 The `info proc' command will print out information about any process
3570 on an SVR4 system (including the one you are debugging). At the moment,
3571 it prints the address mappings of the process.
3573 If you bring up GDB on another SVR4 system, please send mail to
3574 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3576 * Better dynamic linking support in SunOS
3578 Reading symbols from shared libraries which contain debugging symbols
3579 now works properly. However, there remain issues such as automatic
3580 skipping of `transfer vector' code during function calls, which
3581 make it harder to debug code in a shared library, than to debug the
3582 same code linked statically.
3586 GDB is now using the latest `getopt' routines from the FSF. This
3587 version accepts the -- prefix for options with long names. GDB will
3588 continue to accept the old forms (-option and +option) as well.
3589 Various single letter abbreviations for options have been explicity
3590 added to the option table so that they won't get overshadowed in the
3591 future by other options that begin with the same letter.
3595 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3596 Many assorted bugs have been handled. Many more remain to be handled.
3597 See the various ChangeLog files (primarily in gdb and bfd) for details.
3600 *** Changes in GDB-4.3:
3602 * New machines supported (host and target)
3604 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3605 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3606 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3608 * Almost SCO Unix support
3610 We had hoped to support:
3611 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3612 (except for core file support), but we discovered very late in the release
3613 that it has problems with process groups that render gdb unusable. Sorry
3614 about that. I encourage people to fix it and post the fixes.
3616 * Preliminary ELF and DWARF support
3618 GDB can read ELF object files on System V Release 4, and can handle
3619 debugging records for C, in DWARF format, in ELF files. This support
3620 is preliminary. If you bring up GDB on another SVR4 system, please
3621 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3626 GDB now uses the latest `readline' library. One user-visible change
3627 is that two tabs will list possible command completions, which previously
3628 required typing M-? (meta-question mark, or ESC ?).
3632 The `stepi' bug that many of you noticed has been squashed.
3633 Many bugs in C++ have been handled. Many more remain to be handled.
3634 See the various ChangeLog files (primarily in gdb and bfd) for details.
3636 * State of the MIPS world (in case you wondered):
3638 GDB can understand the symbol tables emitted by the compilers
3639 supplied by most vendors of MIPS-based machines, including DEC. These
3640 symbol tables are in a format that essentially nobody else uses.
3642 Some versions of gcc come with an assembler post-processor called
3643 mips-tfile. This program is required if you want to do source-level
3644 debugging of gcc-compiled programs. I believe FSF does not ship
3645 mips-tfile with gcc version 1, but it will eventually come with gcc
3648 Debugging of g++ output remains a problem. g++ version 1.xx does not
3649 really support it at all. (If you're lucky, you should be able to get
3650 line numbers and stack traces to work, but no parameters or local
3651 variables.) With some work it should be possible to improve the
3654 When gcc version 2 is released, you will have somewhat better luck.
3655 However, even then you will get confusing results for inheritance and
3658 We will eventually provide full debugging of g++ output on
3659 DECstations. This will probably involve some kind of stabs-in-ecoff
3660 encapulation, but the details have not been worked out yet.
3663 *** Changes in GDB-4.2:
3665 * Improved configuration
3667 Only one copy of `configure' exists now, and it is not self-modifying.
3668 Porting BFD is simpler.
3672 The `step' and `next' commands now only stop at the first instruction
3673 of a source line. This prevents the multiple stops that used to occur
3674 in switch statements, for-loops, etc. `Step' continues to stop if a
3675 function that has debugging information is called within the line.
3679 Lots of small bugs fixed. More remain.
3681 * New host supported (not target)
3683 Intel 386 PC clone running Mach i386-none-mach
3686 *** Changes in GDB-4.1:
3688 * Multiple source language support
3690 GDB now has internal scaffolding to handle several source languages.
3691 It determines the type of each source file from its filename extension,
3692 and will switch expression parsing and number formatting to match the
3693 language of the function in the currently selected stack frame.
3694 You can also specifically set the language to be used, with
3695 `set language c' or `set language modula-2'.
3699 GDB now has preliminary support for the GNU Modula-2 compiler,
3700 currently under development at the State University of New York at
3701 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3702 continue through the fall of 1991 and into 1992.
3704 Other Modula-2 compilers are currently not supported, and attempting to
3705 debug programs compiled with them will likely result in an error as the
3706 symbol table is read. Feel free to work on it, though!
3708 There are hooks in GDB for strict type checking and range checking,
3709 in the `Modula-2 philosophy', but they do not currently work.
3713 GDB can now write to executable and core files (e.g. patch
3714 a variable's value). You must turn this switch on, specify
3715 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3716 by assigning a new value to a variable. Modifications take
3719 * Automatic SunOS shared library reading
3721 When you run your program, GDB automatically determines where its
3722 shared libraries (if any) have been loaded, and reads their symbols.
3723 The `share' command is no longer needed. This also works when
3724 examining core files.
3728 You can specify the number of lines that the `list' command shows.
3731 * New machines supported (host and target)
3733 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3734 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3735 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3737 * New hosts supported (not targets)
3739 IBM RT/PC: romp-ibm-aix or rtpc
3741 * New targets supported (not hosts)
3743 AMD 29000 embedded with COFF a29k-none-coff
3744 AMD 29000 embedded with a.out a29k-none-aout
3745 Ultracomputer remote kernel debug a29k-nyu-kern
3747 * New remote interfaces
3753 *** Changes in GDB-4.0:
3757 Wide output is wrapped at good places to make the output more readable.
3759 Gdb now supports cross-debugging from a host machine of one type to a
3760 target machine of another type. Communication with the target system
3761 is over serial lines. The ``target'' command handles connecting to the
3762 remote system; the ``load'' command will download a program into the
3763 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3764 also supports debugging of realtime processes running under VxWorks,
3765 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3766 stub on the target system.
3768 New CPUs supported include the AMD 29000 and Intel 960.
3770 GDB now reads object files and symbol tables via a ``binary file''
3771 library, which allows a single copy of GDB to debug programs of multiple
3772 object file types such as a.out and coff.
3774 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3775 refcard.dvi and refcard.ps are available to format it).
3778 * Control-Variable user interface simplified
3780 All variables that control the operation of the debugger can be set
3781 by the ``set'' command, and displayed by the ``show'' command.
3783 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3784 ``Show prompt'' produces the response:
3785 Gdb's prompt is new-gdb=>.
3787 What follows are the NEW set commands. The command ``help set'' will
3788 print a complete list of old and new set commands. ``help set FOO''
3789 will give a longer description of the variable FOO. ``show'' will show
3790 all of the variable descriptions and their current settings.
3792 confirm on/off: Enables warning questions for operations that are
3793 hard to recover from, e.g. rerunning the program while
3794 it is already running. Default is ON.
3796 editing on/off: Enables EMACS style command line editing
3797 of input. Previous lines can be recalled with
3798 control-P, the current line can be edited with control-B,
3799 you can search for commands with control-R, etc.
3802 history filename NAME: NAME is where the gdb command history
3803 will be stored. The default is .gdb_history,
3804 or the value of the environment variable
3807 history size N: The size, in commands, of the command history. The
3808 default is 256, or the value of the environment variable
3811 history save on/off: If this value is set to ON, the history file will
3812 be saved after exiting gdb. If set to OFF, the
3813 file will not be saved. The default is OFF.
3815 history expansion on/off: If this value is set to ON, then csh-like
3816 history expansion will be performed on
3817 command line input. The default is OFF.
3819 radix N: Sets the default radix for input and output. It can be set
3820 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3821 in the current radix, so "set radix 10" is always a no-op.
3823 height N: This integer value is the number of lines on a page. Default
3824 is 24, the current `stty rows'' setting, or the ``li#''
3825 setting from the termcap entry matching the environment
3828 width N: This integer value is the number of characters on a line.
3829 Default is 80, the current `stty cols'' setting, or the ``co#''
3830 setting from the termcap entry matching the environment
3833 Note: ``set screensize'' is obsolete. Use ``set height'' and
3834 ``set width'' instead.
3836 print address on/off: Print memory addresses in various command displays,
3837 such as stack traces and structure values. Gdb looks
3838 more ``symbolic'' if you turn this off; it looks more
3839 ``machine level'' with it on. Default is ON.
3841 print array on/off: Prettyprint arrays. New convenient format! Default
3844 print demangle on/off: Print C++ symbols in "source" form if on,
3847 print asm-demangle on/off: Same, for assembler level printouts
3850 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3853 * Support for Epoch Environment.
3855 The epoch environment is a version of Emacs v18 with windowing. One
3856 new command, ``inspect'', is identical to ``print'', except that if you
3857 are running in the epoch environment, the value is printed in its own
3861 * Support for Shared Libraries
3863 GDB can now debug programs and core files that use SunOS shared libraries.
3864 Symbols from a shared library cannot be referenced
3865 before the shared library has been linked with the program (this
3866 happens after you type ``run'' and before the function main() is entered).
3867 At any time after this linking (including when examining core files
3868 from dynamically linked programs), gdb reads the symbols from each
3869 shared library when you type the ``sharedlibrary'' command.
3870 It can be abbreviated ``share''.
3872 sharedlibrary REGEXP: Load shared object library symbols for files
3873 matching a unix regular expression. No argument
3874 indicates to load symbols for all shared libraries.
3876 info sharedlibrary: Status of loaded shared libraries.
3881 A watchpoint stops execution of a program whenever the value of an
3882 expression changes. Checking for this slows down execution
3883 tremendously whenever you are in the scope of the expression, but is
3884 quite useful for catching tough ``bit-spreader'' or pointer misuse
3885 problems. Some machines such as the 386 have hardware for doing this
3886 more quickly, and future versions of gdb will use this hardware.
3888 watch EXP: Set a watchpoint (breakpoint) for an expression.
3890 info watchpoints: Information about your watchpoints.
3892 delete N: Deletes watchpoint number N (same as breakpoints).
3893 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3894 enable N: Re-enables watchpoint number N (same as breakpoints).
3897 * C++ multiple inheritance
3899 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3902 * C++ exception handling
3904 Gdb now supports limited C++ exception handling. Besides the existing
3905 ability to breakpoint on an exception handler, gdb can breakpoint on
3906 the raising of an exception (before the stack is peeled back to the
3909 catch FOO: If there is a FOO exception handler in the dynamic scope,
3910 set a breakpoint to catch exceptions which may be raised there.
3911 Multiple exceptions (``catch foo bar baz'') may be caught.
3913 info catch: Lists all exceptions which may be caught in the
3914 current stack frame.
3917 * Minor command changes
3919 The command ``call func (arg, arg, ...)'' now acts like the print
3920 command, except it does not print or save a value if the function's result
3921 is void. This is similar to dbx usage.
3923 The ``up'' and ``down'' commands now always print the frame they end up
3924 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3925 frames without printing.
3927 * New directory command
3929 'dir' now adds directories to the FRONT of the source search path.
3930 The path starts off empty. Source files that contain debug information
3931 about the directory in which they were compiled can be found even
3932 with an empty path; Sun CC and GCC include this information. If GDB can't
3933 find your source file in the current directory, type "dir .".
3935 * Configuring GDB for compilation
3937 For normal use, type ``./configure host''. See README or gdb.texinfo
3940 GDB now handles cross debugging. If you are remotely debugging between
3941 two different machines, type ``./configure host -target=targ''.
3942 Host is the machine where GDB will run; targ is the machine
3943 where the program that you are debugging will run.