1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.0
8 Xilinx MicroBlaze microblaze-*-*
13 Xilinx MicroBlaze microblaze
16 * Multi-program debugging.
18 GDB now has support for multi-program (a.k.a. multi-executable or
19 multi-exec) debugging. This allows for debugging multiple inferiors
20 simultaneously each running a different program under the same GDB
21 session. See "Debugging Multiple Inferiors and Programs" in the
22 manual for more information. This implied some user visible changes
23 in the multi-inferior support. For example, "info inferiors" now
24 lists inferiors that are not running yet or that have exited
25 already. See also "New commands" and "New options" below.
27 * New tracing features
29 GDB's tracepoint facility now includes several new features:
31 ** Trace state variables
33 GDB tracepoints now include support for trace state variables, which
34 are variables managed by the target agent during a tracing
35 experiment. They are useful for tracepoints that trigger each
36 other, so for instance one tracepoint can count hits in a variable,
37 and then a second tracepoint has a condition that is true when the
38 count reaches a particular value. Trace state variables share the
39 $-syntax of GDB convenience variables, and can appear in both
40 tracepoint actions and condition expressions. Use the "tvariable"
41 command to create, and "info tvariables" to view; see "Trace State
42 Variables" in the manual for more detail.
46 GDB now includes an option for defining fast tracepoints, which
47 targets may implement more efficiently, such as by installing a jump
48 into the target agent rather than a trap instruction. The resulting
49 speedup can be by two orders of magnitude or more, although the
50 tradeoff is that some program locations on some target architectures
51 might not allow fast tracepoint installation, for instance if the
52 instruction to be replaced is shorter than the jump. To request a
53 fast tracepoint, use the "ftrace" command, with syntax identical to
54 the regular trace command.
56 ** Disconnected tracing
58 It is now possible to detach GDB from the target while it is running
59 a trace experiment, then reconnect later to see how the experiment
60 is going. In addition, a new variable disconnected-tracing lets you
61 tell the target agent whether to continue running a trace if the
62 connection is lost unexpectedly.
66 GDB now has the ability to save the trace buffer into a file, and
67 then use that file as a target, similarly to you can do with
68 corefiles. You can select trace frames, print data that was
69 collected in them, and use tstatus to display the state of the
70 tracing run at the moment that it was saved. To create a trace
71 file, use "tsave <filename>", and to use it, do "target tfile
77 The disassemble command, when invoked with two arguments, now requires
78 the arguments to be comma-separated.
81 The info variables command now displays variable definitions. Files
82 which only declare a variable are not shown.
85 The source command is now capable of sourcing Python scripts.
86 This feature is dependent on the debugger being build with Python
89 Related to this enhancement is also the introduction of a new command
90 "set script-extension" (see below).
92 * New commands (for set/show, see "New options" below)
94 record save [<FILENAME>]
95 Save a file (in core file format) containing the process record
96 execution log for replay debugging at a later time.
98 record restore <FILENAME>
99 Restore the process record execution log that was saved at an
100 earlier time, for replay debugging.
102 add-inferior [-copies <N>] [-exec <FILENAME>]
105 clone-inferior [-copies <N>] [ID]
106 Make a new inferior ready to execute the same program another
112 maint info program-spaces
113 List the program spaces loaded into GDB.
115 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
116 show remote interrupt-sequence
117 Allow the user to select one of ^C, a BREAK signal or BREAK-g
118 as the sequence to the remote target in order to interrupt the execution.
119 Ctrl-C is a default. Some system prefers BREAK which is high level of
120 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
121 Magic SysRq g. It is BREAK signal and character 'g'.
123 set remote interrupt-on-connect [on | off]
124 show remote interrupt-on-connect
125 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
126 remote target when gdb connects to it. This is needed when you debug
129 set remotebreak [on | off]
131 Deprecated. Use "set/show remote interrupt-sequence" instead.
133 tvariable $NAME [ = EXP ]
134 Create or modify a trace state variable.
137 List trace state variables and their values.
139 delete tvariable $NAME ...
140 Delete one or more trace state variables.
143 Evaluate the given expressions without collecting anything into the
144 trace buffer. (Valid in tracepoint actions only.)
146 ftrace FN / FILE:LINE / *ADDR
147 Define a fast tracepoint at the given function, line, or address.
149 * New expression syntax
151 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
152 GDB now parses 0b101010 identically with 42.
156 set follow-exec-mode new|same
157 show follow-exec-mode
158 Control whether GDB reuses the same inferior across an exec call or
159 creates a new one. This is useful to be able to restart the old
160 executable after the inferior having done an exec call.
162 set default-collect EXPR, ...
164 Define a list of expressions to be collected at each tracepoint.
165 This is a useful way to ensure essential items are not overlooked,
166 such as registers or a critical global variable.
168 set disconnected-tracing
169 show disconnected-tracing
170 If set to 1, the target is instructed to continue tracing if it
171 loses its connection to GDB. If 0, the target is to stop tracing
174 set script-extension off|soft|strict
175 show script-extension
176 If set to "off", the debugger does not perform any script language
177 recognition, and all sourced files are assumed to be GDB scripts.
178 If set to "soft" (the default), files are sourced according to
179 filename extension, falling back to GDB scripts if the first
181 If set to "strict", files are sourced according to filename extension.
186 Define a trace state variable.
189 Get the current value of a trace state variable.
192 Set desired tracing behavior upon disconnection.
195 Get data about the tracepoints currently in use.
199 Process record now works correctly with hardware watchpoints.
201 Multiple bug fixes have been made to the mips-irix port, making it
202 much more reliable. In particular:
203 - Debugging threaded applications is now possible again. Previously,
204 GDB would hang while starting the program, or while waiting for
205 the program to stop at a breakpoint.
206 - Attaching to a running process no longer hangs.
207 - An error occurring while loading a core file has been fixed.
208 - Changing the value of the PC register now works again. This fixes
209 problems observed when using the "jump" command, or when calling
210 a function from GDB, or even when assigning a new value to $pc.
211 - With the "finish" and "return" commands, the return value for functions
212 returning a small array is now correctly printed.
213 - It is now possible to break on shared library code which gets executed
214 during a shared library init phase (code executed while executing
215 their .init section). Previously, the breakpoint would have no effect.
216 - GDB is now able to backtrace through the signal handler for
217 non-threaded programs.
219 PIE (Position Independent Executable) programs debugging is now supported.
220 This includes debugging execution of PIC (Position Independent Code) shared
221 libraries although for that, it should be possible to run such libraries as an
224 *** Changes in GDB 7.0
226 * GDB now has an interface for JIT compilation. Applications that
227 dynamically generate code can create symbol files in memory and register
228 them with GDB. For users, the feature should work transparently, and
229 for JIT developers, the interface is documented in the GDB manual in the
230 "JIT Compilation Interface" chapter.
232 * Tracepoints may now be conditional. The syntax is as for
233 breakpoints; either an "if" clause appended to the "trace" command,
234 or the "condition" command is available. GDB sends the condition to
235 the target for evaluation using the same bytecode format as is used
236 for tracepoint actions.
238 * "disassemble" command with a /r modifier, print the raw instructions
239 in hex as well as in symbolic form."
241 * Process record and replay
243 In a architecture environment that supports ``process record and
244 replay'', ``process record and replay'' target can record a log of
245 the process execution, and replay it with both forward and reverse
248 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
249 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
250 set execution-direction {forward|reverse}, for targets that support
253 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
254 feature is available with a native GDB running on kernel version
257 * GDB now has support for multi-byte and wide character sets on the
258 target. Strings whose character type is wchar_t, char16_t, or
259 char32_t are now correctly printed. GDB supports wide- and unicode-
260 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
261 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
262 `printf'. This feature requires iconv to work properly; if your
263 system does not have a working iconv, GDB can use GNU libiconv. See
264 the installation instructions for more information.
266 * GDB now supports automatic retrieval of shared library files from
267 remote targets. To use this feature, specify a system root that begins
268 with the `remote:' prefix, either via the `set sysroot' command or via
269 the `--with-sysroot' configure-time option.
271 * "info sharedlibrary" now takes an optional regex of libraries to show,
272 and it now reports if a shared library has no debugging information.
274 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
275 now complete on file names.
277 * When completing in expressions, gdb will attempt to limit
278 completions to allowable structure or union fields, where appropriate.
279 For instance, consider:
281 # struct example { int f1; double f2; };
282 # struct example variable;
285 If the user types TAB at the end of this command line, the available
286 completions will be "f1" and "f2".
288 * Inlined functions are now supported. They show up in backtraces, and
289 the "step", "next", and "finish" commands handle them automatically.
291 * GDB now supports the token-splicing (##) and stringification (#)
292 operators when expanding macros. It also supports variable-arity
295 * GDB now supports inspecting extra signal information, exported by
296 the new $_siginfo convenience variable. The feature is currently
297 implemented on linux ARM, i386 and amd64.
299 * GDB can now display the VFP floating point registers and NEON vector
300 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
301 can provide these registers (requires Linux 2.6.30 or later). Remote
302 and simulator targets may also provide them.
307 Search memory for a sequence of bytes.
310 Turn off `+'/`-' protocol acknowledgments to permit more efficient
311 operation over reliable transport links. Use of this packet is
312 controlled by the `set remote noack-packet' command.
315 Kill the process with the specified process ID. Use this in preference
316 to `k' when multiprocess protocol extensions are supported.
319 Obtains additional operating system information
323 Read or write additional signal information.
325 * Removed remote protocol undocumented extension
327 An undocumented extension to the remote protocol's `S' stop reply
328 packet that permited the stub to pass a process id was removed.
329 Remote servers should use the `T' stop reply packet instead.
331 * The "disassemble" command now supports an optional /m modifier to print mixed
334 * GDB now supports multiple function calling conventions according to the
335 DWARF-2 DW_AT_calling_convention function attribute.
337 * The SH target utilizes the aforementioned change to distinguish between gcc
338 and Renesas calling convention. It also adds the new CLI commands
339 `set/show sh calling-convention'.
341 * GDB can now read compressed debug sections, as produced by GNU gold
342 with the --compress-debug-sections=zlib flag.
344 * 64-bit core files are now supported on AIX.
346 * Thread switching is now supported on Tru64.
348 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
349 which will be allocated using malloc later in program execution.
351 * The qXfer:libraries:read remote procotol packet now allows passing a
352 list of section offsets.
354 * On GNU/Linux, GDB can now attach to stopped processes. Several race
355 conditions handling signals delivered during attach or thread creation
356 have also been fixed.
358 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
359 From the user's standpoint, all unqualified instances of True and False
360 are treated as the standard definitions, regardless of context.
362 * GDB now parses C++ symbol and type names more flexibly. For
365 template<typename T> class C { };
368 GDB will now correctly handle all of:
370 ptype C<char const *>
372 ptype C<const char *>
375 * New features in the GDB remote stub, gdbserver
377 - The "--wrapper" command-line argument tells gdbserver to use a
378 wrapper program to launch programs for debugging.
380 - On PowerPC and S/390 targets, it is now possible to use a single
381 gdbserver executable to debug both 32-bit and 64-bit programs.
382 (This requires gdbserver itself to be built as a 64-bit executable.)
384 - gdbserver uses the new noack protocol mode for TCP connections to
385 reduce communications latency, if also supported and enabled in GDB.
387 - Support for the sparc64-linux-gnu target is now included in
390 - The amd64-linux build of gdbserver now supports debugging both
391 32-bit and 64-bit programs.
393 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
394 now support hardware watchpoints, and will use them automatically
399 GDB now has support for scripting using Python. Whether this is
400 available is determined at configure time.
402 New GDB commands can now be written in Python.
404 * Ada tasking support
406 Ada tasks can now be inspected in GDB. The following commands have
410 Print the list of Ada tasks.
412 Print detailed information about task number N.
414 Print the task number of the current task.
416 Switch the context of debugging to task number N.
418 * Support for user-defined prefixed commands. The "define" command can
419 add new commands to existing prefixes, e.g. "target".
421 * Multi-inferior, multi-process debugging.
423 GDB now has generalized support for multi-inferior debugging. See
424 "Debugging Multiple Inferiors" in the manual for more information.
425 Although availability still depends on target support, the command
426 set is more uniform now. The GNU/Linux specific multi-forks support
427 has been migrated to this new framework. This implied some user
428 visible changes; see "New commands" and also "Removed commands"
431 * Target descriptions can now describe the target OS ABI. See the
432 "Target Description Format" section in the user manual for more
435 * Target descriptions can now describe "compatible" architectures
436 to indicate that the target can execute applications for a different
437 architecture in addition to those for the main target architecture.
438 See the "Target Description Format" section in the user manual for
441 * Multi-architecture debugging.
443 GDB now includes general supports for debugging applications on
444 hybrid systems that use more than one single processor architecture
445 at the same time. Each such hybrid architecture still requires
446 specific support to be added. The only hybrid architecture supported
447 in this version of GDB is the Cell Broadband Engine.
449 * GDB now supports integrated debugging of Cell/B.E. applications that
450 use both the PPU and SPU architectures. To enable support for hybrid
451 Cell/B.E. debugging, you need to configure GDB to support both the
452 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
453 --enable-targets configure option.
455 * Non-stop mode debugging.
457 For some targets, GDB now supports an optional mode of operation in
458 which you can examine stopped threads while other threads continue
459 to execute freely. This is referred to as non-stop mode, with the
460 old mode referred to as all-stop mode. See the "Non-Stop Mode"
461 section in the user manual for more information.
463 To be able to support remote non-stop debugging, a remote stub needs
464 to implement the non-stop mode remote protocol extensions, as
465 described in the "Remote Non-Stop" section of the user manual. The
466 GDB remote stub, gdbserver, has been adjusted to support these
467 extensions on linux targets.
469 * New commands (for set/show, see "New options" below)
471 catch syscall [NAME(S) | NUMBER(S)]
472 Catch system calls. Arguments, which should be names of system
473 calls or their numbers, mean catch only those syscalls. Without
474 arguments, every syscall will be caught. When the inferior issues
475 any of the specified syscalls, GDB will stop and announce the system
476 call, both when it is called and when its call returns. This
477 feature is currently available with a native GDB running on the
478 Linux Kernel, under the following architectures: x86, x86_64,
479 PowerPC and PowerPC64.
481 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
483 Search memory for a sequence of bytes.
485 maint set python print-stack
486 maint show python print-stack
487 Show a stack trace when an error is encountered in a Python script.
490 Invoke CODE by passing it to the Python interpreter.
495 These allow macros to be defined, undefined, and listed
499 Show operating system information about processes.
502 List the inferiors currently under GDB's control.
505 Switch focus to inferior number NUM.
508 Detach from inferior number NUM.
511 Kill inferior number NUM.
516 show spu stop-on-load
517 Control whether to stop for new SPE threads during Cell/B.E. debugging.
519 set spu auto-flush-cache
520 show spu auto-flush-cache
521 Control whether to automatically flush the software-managed cache
522 during Cell/B.E. debugging.
524 set sh calling-convention
525 show sh calling-convention
526 Control the calling convention used when calling SH target functions.
530 Control display of timestamps with GDB debugging output.
532 set disassemble-next-line
533 show disassemble-next-line
534 Control display of disassembled source lines or instructions when
537 set remote noack-packet
538 show remote noack-packet
539 Set/show the use of remote protocol QStartNoAckMode packet. See above
540 under "New remote packets."
542 set remote query-attached-packet
543 show remote query-attached-packet
544 Control use of remote protocol `qAttached' (query-attached) packet.
546 set remote read-siginfo-object
547 show remote read-siginfo-object
548 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
551 set remote write-siginfo-object
552 show remote write-siginfo-object
553 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
556 set remote reverse-continue
557 show remote reverse-continue
558 Control use of remote protocol 'bc' (reverse-continue) packet.
560 set remote reverse-step
561 show remote reverse-step
562 Control use of remote protocol 'bs' (reverse-step) packet.
564 set displaced-stepping
565 show displaced-stepping
566 Control displaced stepping mode. Displaced stepping is a way to
567 single-step over breakpoints without removing them from the debuggee.
568 Also known as "out-of-line single-stepping".
572 Control display of debugging info for displaced stepping.
574 maint set internal-error
575 maint show internal-error
576 Control what GDB does when an internal error is detected.
578 maint set internal-warning
579 maint show internal-warning
580 Control what GDB does when an internal warning is detected.
585 Use a wrapper program to launch programs for debugging.
587 set multiple-symbols (all|ask|cancel)
588 show multiple-symbols
589 The value of this variable can be changed to adjust the debugger behavior
590 when an expression or a breakpoint location contains an ambiguous symbol
591 name (an overloaded function name, for instance).
593 set breakpoint always-inserted
594 show breakpoint always-inserted
595 Keep breakpoints always inserted in the target, as opposed to inserting
596 them when resuming the target, and removing them when the target stops.
597 This option can improve debugger performance on slow remote targets.
599 set arm fallback-mode (arm|thumb|auto)
600 show arm fallback-mode
601 set arm force-mode (arm|thumb|auto)
603 These commands control how ARM GDB determines whether instructions
604 are ARM or Thumb. The default for both settings is auto, which uses
605 the current CPSR value for instructions without symbols; previous
606 versions of GDB behaved as if "set arm fallback-mode arm".
608 set disable-randomization
609 show disable-randomization
610 Standalone programs run with the virtual address space randomization enabled
611 by default on some platforms. This option keeps the addresses stable across
612 multiple debugging sessions.
616 Control whether other threads are stopped or not when some thread hits
621 Requests that asynchronous execution is enabled in the target, if available.
622 In this case, it's possible to resume target in the background, and interact
623 with GDB while the target is running. "show target-async" displays the
624 current state of asynchronous execution of the target.
626 set target-wide-charset
627 show target-wide-charset
628 The target-wide-charset is the name of the character set that GDB
629 uses when printing characters whose type is wchar_t.
631 set tcp auto-retry (on|off)
633 set tcp connect-timeout
634 show tcp connect-timeout
635 These commands allow GDB to retry failed TCP connections to a remote stub
636 with a specified timeout period; this is useful if the stub is launched
637 in parallel with GDB but may not be ready to accept connections immediately.
639 set libthread-db-search-path
640 show libthread-db-search-path
641 Control list of directories which GDB will search for appropriate
644 set schedule-multiple (on|off)
645 show schedule-multiple
646 Allow GDB to resume all threads of all processes or only threads of
651 Use more aggressive caching for accesses to the stack. This improves
652 performance of remote debugging (particularly backtraces) without
653 affecting correctness.
655 set interactive-mode (on|off|auto)
656 show interactive-mode
657 Control whether GDB runs in interactive mode (on) or not (off).
658 When in interactive mode, GDB waits for the user to answer all
659 queries. Otherwise, GDB does not wait and assumes the default
660 answer. When set to auto (the default), GDB determines which
661 mode to use based on the stdin settings.
666 For program forks, this is replaced by the new more generic `info
667 inferiors' command. To list checkpoints, you can still use the
668 `info checkpoints' command, which was an alias for the `info forks'
672 Replaced by the new `inferior' command. To switch between
673 checkpoints, you can still use the `restart' command, which was an
674 alias for the `fork' command.
677 This is removed, since some targets don't have a notion of
678 processes. To switch between processes, you can still use the
679 `inferior' command using GDB's own inferior number.
682 For program forks, this is replaced by the new more generic `kill
683 inferior' command. To delete a checkpoint, you can still use the
684 `delete checkpoint' command, which was an alias for the `delete
688 For program forks, this is replaced by the new more generic `detach
689 inferior' command. To detach a checkpoint, you can still use the
690 `detach checkpoint' command, which was an alias for the `detach
693 * New native configurations
695 x86/x86_64 Darwin i[34567]86-*-darwin*
697 x86_64 MinGW x86_64-*-mingw*
701 Lattice Mico32 lm32-*
702 x86 DICOS i[34567]86-*-dicos*
703 x86_64 DICOS x86_64-*-dicos*
706 * The GDB remote stub, gdbserver, now supports x86 Windows CE
707 (mingw32ce) debugging.
713 These commands were actually not implemented on any target.
715 *** Changes in GDB 6.8
717 * New native configurations
719 NetBSD/hppa hppa*-*netbsd*
720 Xtensa GNU/Linux xtensa*-*-linux*
724 NetBSD/hppa hppa*-*-netbsd*
725 Xtensa GNU/Lunux xtensa*-*-linux*
727 * Change in command line behavior -- corefiles vs. process ids.
729 When the '-p NUMBER' or '--pid NUMBER' options are used, and
730 attaching to process NUMBER fails, GDB no longer attempts to open a
731 core file named NUMBER. Attaching to a program using the -c option
732 is no longer supported. Instead, use the '-p' or '--pid' options.
734 * GDB can now be built as a native debugger for debugging Windows x86
735 (mingw32) Portable Executable (PE) programs.
737 * Pending breakpoints no longer change their number when their address
740 * GDB now supports breakpoints with multiple locations,
741 including breakpoints on C++ constructors, inside C++ templates,
742 and in inlined functions.
744 * GDB's ability to debug optimized code has been improved. GDB more
745 accurately identifies function bodies and lexical blocks that occupy
746 more than one contiguous range of addresses.
748 * Target descriptions can now describe registers for PowerPC.
750 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
751 registers on PowerPC targets.
753 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
754 targets even when the libthread_db library is not available.
756 * The GDB remote stub, gdbserver, now supports the new file transfer
757 commands (remote put, remote get, and remote delete).
759 * The GDB remote stub, gdbserver, now supports run and attach in
760 extended-remote mode.
762 * hppa*64*-*-hpux11* target broken
763 The debugger is unable to start a program and fails with the following
764 error: "Error trying to get information about dynamic linker".
765 The gdb-6.7 release is also affected.
767 * GDB now supports the --enable-targets= configure option to allow
768 building a single GDB executable that supports multiple remote
769 target architectures.
771 * GDB now supports debugging C and C++ programs which use the
772 Decimal Floating Point extension. In addition, the PowerPC target
773 now has a set of pseudo-registers to inspect decimal float values
774 stored in two consecutive float registers.
776 * The -break-insert MI command can optionally create pending
779 * Improved support for debugging Ada
780 Many improvements to the Ada language support have been made. These
782 - Better support for Ada2005 interface types
783 - Improved handling of arrays and slices in general
784 - Better support for Taft-amendment types
785 - The '{type} ADDRESS' expression is now allowed on the left hand-side
787 - Improved command completion in Ada
790 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
795 set print frame-arguments (all|scalars|none)
796 show print frame-arguments
797 The value of this variable can be changed to control which argument
798 values should be printed by the debugger when displaying a frame.
803 Transfer files to and from a remote target, and delete remote files.
810 Transfer files to and from a remote target, and delete remote files.
819 Open, close, read, write, and delete files on the remote system.
822 Attach to an existing process on the remote system, in extended-remote
826 Run a new process on the remote system, in extended-remote mode.
828 *** Changes in GDB 6.7
830 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
831 bfd, libiberty and opcodes, as revealed by static analysis donated by
832 Coverity, Inc. (http://scan.coverity.com).
834 * When looking up multiply-defined global symbols, GDB will now prefer the
835 symbol definition in the current shared library if it was built using the
836 -Bsymbolic linker option.
838 * When the Text User Interface (TUI) is not configured, GDB will now
839 recognize the -tui command-line option and print a message that the TUI
842 * The GDB remote stub, gdbserver, now has lower overhead for high
843 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
845 * GDB for MIPS targets now autodetects whether a remote target provides
846 32-bit or 64-bit register values.
848 * Support for C++ member pointers has been improved.
850 * GDB now understands XML target descriptions, which specify the
851 target's overall architecture. GDB can read a description from
852 a local file or over the remote serial protocol.
854 * Vectors of single-byte data use a new integer type which is not
855 automatically displayed as character or string data.
857 * The /s format now works with the print command. It displays
858 arrays of single-byte integers and pointers to single-byte integers
861 * Target descriptions can now describe target-specific registers,
862 for architectures which have implemented the support (currently
863 only ARM, M68K, and MIPS).
865 * GDB and the GDB remote stub, gdbserver, now support the XScale
868 * The GDB remote stub, gdbserver, has been updated to support
869 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
870 has been rewritten to use the standard GDB remote protocol.
872 * GDB can now step into C++ functions which are called through thunks.
874 * GDB for the Cell/B.E. SPU now supports overlay debugging.
876 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
877 layout. It also supports a TextSeg= and DataSeg= response when only
878 segment base addresses (rather than offsets) are available.
880 * The /i format now outputs any trailing branch delay slot instructions
881 immediately following the last instruction within the count specified.
883 * The GDB remote protocol "T" stop reply packet now supports a
884 "library" response. Combined with the new "qXfer:libraries:read"
885 packet, this response allows GDB to debug shared libraries on targets
886 where the operating system manages the list of loaded libraries (e.g.
887 Windows and SymbianOS).
889 * The GDB remote stub, gdbserver, now supports dynamic link libraries
890 (DLLs) on Windows and Windows CE targets.
892 * GDB now supports a faster verification that a .debug file matches its binary
893 according to its build-id signature, if the signature is present.
899 Enable or disable hardware flow control (RTS/CTS) on the serial port
900 when debugging using remote targets.
902 set mem inaccessible-by-default
903 show mem inaccessible-by-default
904 If the target supplies a memory map, for instance via the remote
905 protocol's "qXfer:memory-map:read" packet, setting this variable
906 prevents GDB from accessing memory outside the memory map. This
907 is useful for targets with memory mapped registers or which react
908 badly to accesses of unmapped address space.
910 set breakpoint auto-hw
911 show breakpoint auto-hw
912 If the target supplies a memory map, for instance via the remote
913 protocol's "qXfer:memory-map:read" packet, setting this variable
914 lets GDB use hardware breakpoints automatically for memory regions
915 where it can not use software breakpoints. This covers both the
916 "break" command and internal breakpoints used for other commands
917 including "next" and "finish".
920 catch exception unhandled
921 Stop the program execution when Ada exceptions are raised.
924 Stop the program execution when an Ada assertion failed.
928 Set an alternate system root for target files. This is a more
929 general version of "set solib-absolute-prefix", which is now
930 an alias to "set sysroot".
933 Provide extended SPU facility status information. This set of
934 commands is available only when debugging the Cell/B.E. SPU
937 * New native configurations
939 OpenBSD/sh sh*-*openbsd*
944 Use the specified local file as an XML target description, and do
945 not query the target for its built-in description.
949 OpenBSD/sh sh*-*-openbsd*
950 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
951 Toshiba Media Processor mep-elf
956 Ignore the specified signals; pass them directly to the debugged program
957 without stopping other threads or reporting them to GDB.
960 Read an XML target description from the target, which describes its
965 Read or write contents of an spufs file on the target system. These
966 packets are available only on the Cell/B.E. SPU architecture.
968 qXfer:libraries:read:
969 Report the loaded shared libraries. Combined with new "T" packet
970 response, this packet allows GDB to debug shared libraries on
971 targets where the operating system manages the list of loaded
972 libraries (e.g. Windows and SymbianOS).
976 Support for these obsolete configurations has been removed.
985 i[34567]86-*-netware*
986 i[34567]86-*-sco3.2v5*
987 i[34567]86-*-sco3.2v4*
989 i[34567]86-*-sysv4.2*
992 i[34567]86-*-unixware2*
993 i[34567]86-*-unixware*
1002 * Other removed features
1009 Various m68k-only ROM monitors.
1016 Various Renesas ROM monitors and debugging interfaces for SH and
1021 Support for a Macraigor serial interface to on-chip debugging.
1022 GDB does not directly support the newer parallel or USB
1027 A debug information format. The predecessor to DWARF 2 and
1028 DWARF 3, which are still supported.
1030 Support for the HP aCC compiler on HP-UX/PA-RISC
1032 SOM-encapsulated symbolic debugging information, automatic
1033 invocation of pxdb, and the aCC custom C++ ABI. This does not
1034 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1035 with aCC can still be debugged on an assembly level.
1037 MIPS ".pdr" sections
1039 A MIPS-specific format used to describe stack frame layout
1040 in debugging information.
1044 GDB could work with an older version of Guile to debug
1045 the interpreter and Scheme programs running in it.
1047 set mips stack-arg-size
1048 set mips saved-gpreg-size
1050 Use "set mips abi" to control parameter passing for MIPS.
1052 *** Changes in GDB 6.6
1057 Cell Broadband Engine SPU spu-elf
1059 * GDB can now be configured as a cross-debugger targeting native Windows
1060 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1061 running on a Windows system over TCP/IP to debug Windows programs.
1063 * The GDB remote stub, gdbserver, has been updated to support Windows and
1064 Cygwin debugging. Both single-threaded and multi-threaded programs are
1067 * The "set trust-readonly-sections" command works again. This command was
1068 broken in GDB 6.3, 6.4, and 6.5.
1070 * The "load" command now supports writing to flash memory, if the remote
1071 stub provides the required support.
1073 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1074 longer requires symbolic debug information (e.g. DWARF-2).
1079 unset substitute-path
1080 show substitute-path
1081 Manage a list of substitution rules that GDB uses to rewrite the name
1082 of the directories where the sources are located. This can be useful
1083 for instance when the sources were moved to a different location
1084 between compilation and debugging.
1088 Print each CLI command as it is executed. Each command is prefixed with
1089 a number of `+' symbols representing the nesting depth.
1090 The source command now has a `-v' option to enable the same feature.
1094 The ARM Demon monitor support (RDP protocol, "target rdp").
1096 Kernel Object Display, an embedded debugging feature which only worked with
1097 an obsolete version of Cisco IOS.
1099 The 'set download-write-size' and 'show download-write-size' commands.
1101 * New remote packets
1104 Tell a stub about GDB client features, and request remote target features.
1105 The first feature implemented is PacketSize, which allows the target to
1106 specify the size of packets it can handle - to minimize the number of
1107 packets required and improve performance when connected to a remote
1111 Fetch an OS auxilliary vector from the remote stub. This packet is a
1112 more efficient replacement for qPart:auxv:read.
1114 qXfer:memory-map:read:
1115 Fetch a memory map from the remote stub, including information about
1116 RAM, ROM, and flash memory devices.
1121 Erase and program a flash memory device.
1123 * Removed remote packets
1126 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1127 used it, and only gdbserver implemented it.
1129 *** Changes in GDB 6.5
1133 Renesas M32C/M16C m32c-elf
1135 Morpho Technologies ms1 ms1-elf
1139 init-if-undefined Initialize a convenience variable, but
1140 only if it doesn't already have a value.
1142 The following commands are presently only implemented for native GNU/Linux:
1144 checkpoint Save a snapshot of the program state.
1146 restart <n> Return the program state to a
1147 previously saved state.
1149 info checkpoints List currently saved checkpoints.
1151 delete-checkpoint <n> Delete a previously saved checkpoint.
1153 set|show detach-on-fork Tell gdb whether to detach from a newly
1154 forked process, or to keep debugging it.
1156 info forks List forks of the user program that
1157 are available to be debugged.
1159 fork <n> Switch to debugging one of several
1160 forks of the user program that are
1161 available to be debugged.
1163 delete-fork <n> Delete a fork from the list of forks
1164 that are available to be debugged (and
1165 kill the forked process).
1167 detach-fork <n> Delete a fork from the list of forks
1168 that are available to be debugged (and
1169 allow the process to continue).
1173 Morpho Technologies ms2 ms1-elf
1175 * Improved Windows host support
1177 GDB now builds as a cross debugger hosted on i686-mingw32, including
1178 native console support, and remote communications using either
1179 network sockets or serial ports.
1181 * Improved Modula-2 language support
1183 GDB can now print most types in the Modula-2 syntax. This includes:
1184 basic types, set types, record types, enumerated types, range types,
1185 pointer types and ARRAY types. Procedure var parameters are correctly
1186 printed and hexadecimal addresses and character constants are also
1187 written in the Modula-2 syntax. Best results can be obtained by using
1188 GNU Modula-2 together with the -gdwarf-2 command line option.
1192 The ARM rdi-share module.
1194 The Netware NLM debug server.
1196 *** Changes in GDB 6.4
1198 * New native configurations
1200 OpenBSD/arm arm*-*-openbsd*
1201 OpenBSD/mips64 mips64-*-openbsd*
1205 Morpho Technologies ms1 ms1-elf
1207 * New command line options
1209 --batch-silent As for --batch, but totally silent.
1210 --return-child-result The debugger will exist with the same value
1211 the child (debugged) program exited with.
1212 --eval-command COMMAND, -ex COMMAND
1213 Execute a single GDB CLI command. This may be
1214 specified multiple times and in conjunction
1215 with the --command (-x) option.
1217 * Deprecated commands removed
1219 The following commands, that were deprecated in 2000, have been
1223 set|show arm disassembly-flavor set|show arm disassembler
1224 othernames set arm disassembler
1225 set|show remotedebug set|show debug remote
1226 set|show archdebug set|show debug arch
1227 set|show eventdebug set|show debug event
1230 * New BSD user-level threads support
1232 It is now possible to debug programs using the user-level threads
1233 library on OpenBSD and FreeBSD. Currently supported (target)
1236 FreeBSD/amd64 x86_64-*-freebsd*
1237 FreeBSD/i386 i386-*-freebsd*
1238 OpenBSD/i386 i386-*-openbsd*
1240 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1241 are not yet supported.
1243 * New support for Matsushita MN10300 w/sim added
1244 (Work in progress). mn10300-elf.
1246 * REMOVED configurations and files
1248 VxWorks and the XDR protocol *-*-vxworks
1249 Motorola MCORE mcore-*-*
1250 National Semiconductor NS32000 ns32k-*-*
1252 * New "set print array-indexes" command
1254 After turning this setting "on", GDB prints the index of each element
1255 when displaying arrays. The default is "off" to preserve the previous
1258 * VAX floating point support
1260 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1262 * User-defined command support
1264 In addition to using $arg0..$arg9 for argument passing, it is now possible
1265 to use $argc to determine now many arguments have been passed. See the
1266 section on user-defined commands in the user manual for more information.
1268 *** Changes in GDB 6.3:
1270 * New command line option
1272 GDB now accepts -l followed by a number to set the timeout for remote
1275 * GDB works with GCC -feliminate-dwarf2-dups
1277 GDB now supports a more compact representation of DWARF-2 debug
1278 information using DW_FORM_ref_addr references. These are produced
1279 by GCC with the option -feliminate-dwarf2-dups and also by some
1280 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1281 to use -feliminate-dwarf2-dups.
1283 * Internationalization
1285 When supported by the host system, GDB will be built with
1286 internationalization (libintl). The task of marking up the sources is
1287 continued, we're looking forward to our first translation.
1291 Initial support for debugging programs compiled with the GNAT
1292 implementation of the Ada programming language has been integrated
1293 into GDB. In this release, support is limited to expression evaluation.
1295 * New native configurations
1297 GNU/Linux/m32r m32r-*-linux-gnu
1301 GDB's remote protocol now includes support for the 'p' packet. This
1302 packet is used to fetch individual registers from a remote inferior.
1304 * END-OF-LIFE registers[] compatibility module
1306 GDB's internal register infrastructure has been completely rewritten.
1307 The new infrastructure making possible the implementation of key new
1308 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1311 GDB 6.3 will be the last release to include the the registers[]
1312 compatibility module that allowed out-of-date configurations to
1313 continue to work. This change directly impacts the following
1323 powerpc bdm protocol
1325 Unless there is activity to revive these configurations, they will be
1326 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1328 * OBSOLETE configurations and files
1330 Configurations that have been declared obsolete in this release have
1331 been commented out. Unless there is activity to revive these
1332 configurations, the next release of GDB will have their sources
1333 permanently REMOVED.
1342 *** Changes in GDB 6.2.1:
1344 * MIPS `break main; run' gave an heuristic-fence-post warning
1346 When attempting to run even a simple program, a warning about
1347 heuristic-fence-post being hit would be reported. This problem has
1350 * MIPS IRIX 'long double' crashed GDB
1352 When examining a long double variable, GDB would get a segmentation
1353 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1354 IRIX long double values).
1358 A bug in the VAX stack code was causing problems with the "next"
1359 command. This problem has been fixed.
1361 *** Changes in GDB 6.2:
1363 * Fix for ``many threads''
1365 On GNU/Linux systems that use the NPTL threads library, a program
1366 rapidly creating and deleting threads would confuse GDB leading to the
1369 ptrace: No such process.
1370 thread_db_get_info: cannot get thread info: generic error
1372 This problem has been fixed.
1374 * "-async" and "-noasync" options removed.
1376 Support for the broken "-noasync" option has been removed (it caused
1379 * New ``start'' command.
1381 This command runs the program until the begining of the main procedure.
1383 * New BSD Kernel Data Access Library (libkvm) interface
1385 Using ``target kvm'' it is now possible to debug kernel core dumps and
1386 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1387 platforms. Currently supported (native-only) configurations are:
1389 FreeBSD/amd64 x86_64-*-freebsd*
1390 FreeBSD/i386 i?86-*-freebsd*
1391 NetBSD/i386 i?86-*-netbsd*
1392 NetBSD/m68k m68*-*-netbsd*
1393 NetBSD/sparc sparc-*-netbsd*
1394 OpenBSD/amd64 x86_64-*-openbsd*
1395 OpenBSD/i386 i?86-*-openbsd*
1396 OpenBSD/m68k m68*-openbsd*
1397 OpenBSD/sparc sparc-*-openbsd*
1399 * Signal trampoline code overhauled
1401 Many generic problems with GDB's signal handling code have been fixed.
1402 These include: backtraces through non-contiguous stacks; recognition
1403 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1404 call; backtrace through a signal trampoline; step into and out of
1405 signal handlers; and single-stepping in the signal trampoline.
1407 Please note that kernel bugs are a limiting factor here. These
1408 features have been shown to work on an s390 GNU/Linux system that
1409 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1411 * Cygwin support for DWARF 2 added.
1413 * New native configurations
1415 GNU/Linux/hppa hppa*-*-linux*
1416 OpenBSD/hppa hppa*-*-openbsd*
1417 OpenBSD/m68k m68*-*-openbsd*
1418 OpenBSD/m88k m88*-*-openbsd*
1419 OpenBSD/powerpc powerpc-*-openbsd*
1420 NetBSD/vax vax-*-netbsd*
1421 OpenBSD/vax vax-*-openbsd*
1423 * END-OF-LIFE frame compatibility module
1425 GDB's internal frame infrastructure has been completely rewritten.
1426 The new infrastructure making it possible to support key new features
1427 including DWARF 2 Call Frame Information. To aid in the task of
1428 migrating old configurations to this new infrastructure, a
1429 compatibility module, that allowed old configurations to continue to
1430 work, was also included.
1432 GDB 6.2 will be the last release to include this frame compatibility
1433 module. This change directly impacts the following configurations:
1443 Unless there is activity to revive these configurations, they will be
1444 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1446 * REMOVED configurations and files
1448 Sun 3, running SunOS 3 m68*-*-sunos3*
1449 Sun 3, running SunOS 4 m68*-*-sunos4*
1450 Sun 2, running SunOS 3 m68000-*-sunos3*
1451 Sun 2, running SunOS 4 m68000-*-sunos4*
1452 Motorola 680x0 running LynxOS m68*-*-lynxos*
1453 AT&T 3b1/Unix pc m68*-att-*
1454 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1455 decstation mips-dec-* mips-little-*
1456 riscos mips-*-riscos* mips-*-sysv*
1457 sonymips mips-sony-*
1458 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1460 *** Changes in GDB 6.1.1:
1462 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1464 The TUI (Text-mode User Interface) is now built as part of a default
1465 GDB configuration. It is enabled by either selecting the TUI with the
1466 command line option "-i=tui" or by running the separate "gdbtui"
1467 program. For more information on the TUI, see the manual "Debugging
1470 * Pending breakpoint support (also included in GDB 6.1)
1472 Support has been added to allow you to specify breakpoints in shared
1473 libraries that have not yet been loaded. If a breakpoint location
1474 cannot be found, and the "breakpoint pending" option is set to auto,
1475 GDB queries you if you wish to make the breakpoint pending on a future
1476 shared-library load. If and when GDB resolves the breakpoint symbol,
1477 the pending breakpoint is removed as one or more regular breakpoints
1480 Pending breakpoints are very useful for GCJ Java debugging.
1482 * Fixed ISO-C build problems
1484 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1485 non ISO-C code that stopped them being built using a more strict ISO-C
1486 compiler (e.g., IBM's C compiler).
1488 * Fixed build problem on IRIX 5
1490 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1491 wasn't able to compile compile on an IRIX 5 system.
1493 * Added execute permission to gdb/gdbserver/configure
1495 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1496 permission. This bug would cause configure to fail on a number of
1497 systems (Solaris, IRIX). Ref: server/519.
1499 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1501 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1502 has been updated to use constant array sizes.
1504 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1506 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1507 its generated DWARF Call Frame Info. This encoding was causing GDB to
1508 panic, that panic has been fixed. Ref: gdb/1628.
1510 * Fixed a problem when examining parameters in shared library code.
1512 When examining parameters in optimized shared library code generated
1513 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1514 not available''. GDB now correctly displays the variable's value.
1516 *** Changes in GDB 6.1:
1518 * Removed --with-mmalloc
1520 Support for the mmalloc memory manager has been removed, as it
1521 conflicted with the internal gdb byte cache.
1523 * Changes in AMD64 configurations
1525 The AMD64 target now includes the %cs and %ss registers. As a result
1526 the AMD64 remote protocol has changed; this affects the floating-point
1527 and SSE registers. If you rely on those registers for your debugging,
1528 you should upgrade gdbserver on the remote side.
1530 * Revised SPARC target
1532 The SPARC target has been completely revised, incorporating the
1533 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1534 support for LynxOS and SunOS 4 has been dropped. Calling functions
1535 from within GDB on operating systems with a non-executable stack
1536 (Solaris, OpenBSD) now works.
1540 GDB has a new C++ demangler which does a better job on the mangled
1541 names generated by current versions of g++. It also runs faster, so
1542 with this and other changes gdb should now start faster on large C++
1545 * DWARF 2 Location Expressions
1547 GDB support for location expressions has been extended to support function
1548 arguments and frame bases. Older versions of GDB could crash when they
1551 * C++ nested types and namespaces
1553 GDB's support for nested types and namespaces in C++ has been
1554 improved, especially if you use the DWARF 2 debugging format. (This
1555 is the default for recent versions of GCC on most platforms.)
1556 Specifically, if you have a class "Inner" defined within a class or
1557 namespace "Outer", then GDB realizes that the class's name is
1558 "Outer::Inner", not simply "Inner". This should greatly reduce the
1559 frequency of complaints about not finding RTTI symbols. In addition,
1560 if you are stopped at inside of a function defined within a namespace,
1561 GDB modifies its name lookup accordingly.
1563 * New native configurations
1565 NetBSD/amd64 x86_64-*-netbsd*
1566 OpenBSD/amd64 x86_64-*-openbsd*
1567 OpenBSD/alpha alpha*-*-openbsd*
1568 OpenBSD/sparc sparc-*-openbsd*
1569 OpenBSD/sparc64 sparc64-*-openbsd*
1571 * New debugging protocols
1573 M32R with SDI protocol m32r-*-elf*
1575 * "set prompt-escape-char" command deleted.
1577 The command "set prompt-escape-char" has been deleted. This command,
1578 and its very obscure effet on GDB's prompt, was never documented,
1579 tested, nor mentioned in the NEWS file.
1581 * OBSOLETE configurations and files
1583 Configurations that have been declared obsolete in this release have
1584 been commented out. Unless there is activity to revive these
1585 configurations, the next release of GDB will have their sources
1586 permanently REMOVED.
1588 Sun 3, running SunOS 3 m68*-*-sunos3*
1589 Sun 3, running SunOS 4 m68*-*-sunos4*
1590 Sun 2, running SunOS 3 m68000-*-sunos3*
1591 Sun 2, running SunOS 4 m68000-*-sunos4*
1592 Motorola 680x0 running LynxOS m68*-*-lynxos*
1593 AT&T 3b1/Unix pc m68*-att-*
1594 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1595 decstation mips-dec-* mips-little-*
1596 riscos mips-*-riscos* mips-*-sysv*
1597 sonymips mips-sony-*
1598 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1600 * REMOVED configurations and files
1602 SGI Irix-4.x mips-sgi-irix4 or iris4
1603 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1604 Z8000 simulator z8k-zilog-none or z8ksim
1605 Matsushita MN10200 w/simulator mn10200-*-*
1606 H8/500 simulator h8500-hitachi-hms or h8500hms
1607 HP/PA running BSD hppa*-*-bsd*
1608 HP/PA running OSF/1 hppa*-*-osf*
1609 HP/PA Pro target hppa*-*-pro*
1610 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1611 386BSD i[3456]86-*-bsd*
1612 Sequent family i[3456]86-sequent-sysv4*
1613 i[3456]86-sequent-sysv*
1614 i[3456]86-sequent-bsd*
1615 SPARC running LynxOS sparc-*-lynxos*
1616 SPARC running SunOS 4 sparc-*-sunos4*
1617 Tsqware Sparclet sparclet-*-*
1618 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1620 *** Changes in GDB 6.0:
1624 Support for debugging the Objective-C programming language has been
1625 integrated into GDB.
1627 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1629 DWARF 2's Call Frame Information makes available compiler generated
1630 information that more exactly describes the program's run-time stack.
1631 By using this information, GDB is able to provide more robust stack
1634 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1635 have been updated to use a new backtrace mechanism which includes
1636 DWARF 2 CFI support.
1640 GDB's remote protocol has been extended to include support for hosted
1641 file I/O (where the remote target uses GDB's file system). See GDB's
1642 remote protocol documentation for details.
1644 * All targets using the new architecture framework.
1646 All of GDB's targets have been updated to use the new internal
1647 architecture framework. The way is now open for future GDB releases
1648 to include cross-architecture native debugging support (i386 on amd64,
1651 * GNU/Linux's Thread Local Storage (TLS)
1653 GDB now includes support for for the GNU/Linux implementation of
1654 per-thread variables.
1656 * GNU/Linux's Native POSIX Thread Library (NPTL)
1658 GDB's thread code has been updated to work with either the new
1659 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1661 * Separate debug info.
1663 GDB, in conjunction with BINUTILS, now supports a mechanism for
1664 automatically loading debug information from a separate file. Instead
1665 of shipping full debug and non-debug versions of system libraries,
1666 system integrators can now instead ship just the stripped libraries
1667 and optional debug files.
1669 * DWARF 2 Location Expressions
1671 DWARF 2 Location Expressions allow the compiler to more completely
1672 describe the location of variables (even in optimized code) to the
1675 GDB now includes preliminary support for location expressions (support
1676 for DW_OP_piece is still missing).
1680 A number of long standing bugs that caused GDB to die while starting a
1681 Java application have been fixed. GDB's Java support is now
1682 considered "useable".
1684 * GNU/Linux support for fork, vfork, and exec.
1686 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1687 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1690 * GDB supports logging output to a file
1692 There are two new commands, "set logging" and "show logging", which can be
1693 used to capture GDB's output to a file.
1695 * The meaning of "detach" has changed for gdbserver
1697 The "detach" command will now resume the application, as documented. To
1698 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1701 * d10v, m68hc11 `regs' command deprecated
1703 The `info registers' command has been updated so that it displays the
1704 registers using a format identical to the old `regs' command.
1708 A new command, "maint set profile on/off", has been added. This command can
1709 be used to enable or disable profiling while running GDB, to profile a
1710 session or a set of commands. In addition there is a new configure switch,
1711 "--enable-profiling", which will cause GDB to be compiled with profiling
1712 data, for more informative profiling results.
1714 * Default MI syntax changed to "mi2".
1716 The default MI (machine interface) syntax, enabled by the command line
1717 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1718 "mi1", can be enabled by specifying the option "-i=mi1".
1720 Support for the original "mi0" syntax (included in GDB 5.0) has been
1723 Fix for gdb/192: removed extraneous space when displaying frame level.
1724 Fix for gdb/672: update changelist is now output in mi list format.
1725 Fix for gdb/702: a -var-assign that updates the value now shows up
1726 in a subsequent -var-update.
1728 * New native configurations.
1730 FreeBSD/amd64 x86_64-*-freebsd*
1732 * Multi-arched targets.
1734 HP/PA HPUX11 hppa*-*-hpux*
1735 Renesas M32R/D w/simulator m32r-*-elf*
1737 * OBSOLETE configurations and files
1739 Configurations that have been declared obsolete in this release have
1740 been commented out. Unless there is activity to revive these
1741 configurations, the next release of GDB will have their sources
1742 permanently REMOVED.
1744 Z8000 simulator z8k-zilog-none or z8ksim
1745 Matsushita MN10200 w/simulator mn10200-*-*
1746 H8/500 simulator h8500-hitachi-hms or h8500hms
1747 HP/PA running BSD hppa*-*-bsd*
1748 HP/PA running OSF/1 hppa*-*-osf*
1749 HP/PA Pro target hppa*-*-pro*
1750 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1751 Sequent family i[3456]86-sequent-sysv4*
1752 i[3456]86-sequent-sysv*
1753 i[3456]86-sequent-bsd*
1754 Tsqware Sparclet sparclet-*-*
1755 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1757 * REMOVED configurations and files
1760 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1761 IBM AIX PS/2 i[3456]86-*-aix
1762 i386 running Mach 3.0 i[3456]86-*-mach3*
1763 i386 running Mach i[3456]86-*-mach*
1764 i386 running OSF/1 i[3456]86-*osf1mk*
1765 HP/Apollo 68k Family m68*-apollo*-sysv*,
1767 m68*-hp-bsd*, m68*-hp-hpux*
1768 Argonaut Risc Chip (ARC) arc-*-*
1769 Mitsubishi D30V d30v-*-*
1770 Fujitsu FR30 fr30-*-elf*
1771 OS/9000 i[34]86-*-os9k
1772 I960 with MON960 i960-*-coff
1774 * MIPS $fp behavior changed
1776 The convenience variable $fp, for the MIPS, now consistently returns
1777 the address of the current frame's base. Previously, depending on the
1778 context, $fp could refer to either $sp or the current frame's base
1779 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1780 The GNU Source-Level Debugger''.
1782 *** Changes in GDB 5.3:
1784 * GNU/Linux shared library multi-threaded performance improved.
1786 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1787 `/proc', in preference to `ptrace' for memory reads. This may result
1788 in an improvement in the start-up time of multi-threaded, shared
1789 library applications when run under GDB. One GDB user writes: ``loads
1790 shared libs like mad''.
1792 * ``gdbserver'' now supports multi-threaded applications on some targets
1794 Support for debugging multi-threaded applications which use
1795 the GNU/Linux LinuxThreads package has been added for
1796 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1797 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1799 * GDB now supports C/C++ preprocessor macros.
1801 GDB now expands preprocessor macro invocations in C/C++ expressions,
1802 and provides various commands for showing macro definitions and how
1805 The new command `macro expand EXPRESSION' expands any macro
1806 invocations in expression, and shows the result.
1808 The new command `show macro MACRO-NAME' shows the definition of the
1809 macro named MACRO-NAME, and where it was defined.
1811 Most compilers don't include information about macros in the debugging
1812 information by default. In GCC 3.1, for example, you need to compile
1813 your program with the options `-gdwarf-2 -g3'. If the macro
1814 information is present in the executable, GDB will read it.
1816 * Multi-arched targets.
1818 DEC Alpha (partial) alpha*-*-*
1819 DEC VAX (partial) vax-*-*
1821 National Semiconductor NS32000 (partial) ns32k-*-*
1822 Motorola 68000 (partial) m68k-*-*
1823 Motorola MCORE mcore-*-*
1827 Fujitsu FRV architecture added by Red Hat frv*-*-*
1830 * New native configurations
1832 Alpha NetBSD alpha*-*-netbsd*
1833 SH NetBSD sh*-*-netbsdelf*
1834 MIPS NetBSD mips*-*-netbsd*
1835 UltraSPARC NetBSD sparc64-*-netbsd*
1837 * OBSOLETE configurations and files
1839 Configurations that have been declared obsolete in this release have
1840 been commented out. Unless there is activity to revive these
1841 configurations, the next release of GDB will have their sources
1842 permanently REMOVED.
1844 Mitsubishi D30V d30v-*-*
1845 OS/9000 i[34]86-*-os9k
1846 IBM AIX PS/2 i[3456]86-*-aix
1847 Fujitsu FR30 fr30-*-elf*
1848 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1849 Argonaut Risc Chip (ARC) arc-*-*
1850 i386 running Mach 3.0 i[3456]86-*-mach3*
1851 i386 running Mach i[3456]86-*-mach*
1852 i386 running OSF/1 i[3456]86-*osf1mk*
1853 HP/Apollo 68k Family m68*-apollo*-sysv*,
1855 m68*-hp-bsd*, m68*-hp-hpux*
1856 I960 with MON960 i960-*-coff
1858 * OBSOLETE languages
1860 CHILL, a Pascal like language used by telecommunications companies.
1862 * REMOVED configurations and files
1864 AMD 29k family via UDI a29k-amd-udi, udi29k
1865 A29K VxWorks a29k-*-vxworks
1866 AMD 29000 embedded, using EBMON a29k-none-none
1867 AMD 29000 embedded with COFF a29k-none-coff
1868 AMD 29000 embedded with a.out a29k-none-aout
1870 testsuite/gdb.hp/gdb.threads-hp/ directory
1872 * New command "set max-user-call-depth <nnn>"
1874 This command allows the user to limit the call depth of user-defined
1875 commands. The default is 1024.
1877 * Changes in FreeBSD/i386 native debugging.
1879 Support for the "generate-core-file" has been added.
1881 * New commands "dump", "append", and "restore".
1883 These commands allow data to be copied from target memory
1884 to a bfd-format or binary file (dump and append), and back
1885 from a file into memory (restore).
1887 * Improved "next/step" support on multi-processor Alpha Tru64.
1889 The previous single-step mechanism could cause unpredictable problems,
1890 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1891 of a software single-step mechanism prevents this.
1893 *** Changes in GDB 5.2.1:
1901 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1902 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1903 Fix, by Joel Brobecker imported from mainline.
1905 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1906 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1907 Fix, by Fred Fish, imported from mainline.
1909 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1910 Surprisingly enough, it works now.
1911 By Michal Ludvig, imported from mainline.
1913 i386 hardware watchpoint support:
1914 avoid misses on second run for some targets.
1915 By Pierre Muller, imported from mainline.
1917 *** Changes in GDB 5.2:
1919 * New command "set trust-readonly-sections on[off]".
1921 This command is a hint that tells gdb that read-only sections
1922 really are read-only (ie. that their contents will not change).
1923 In this mode, gdb will go to the object file rather than the
1924 target to read memory from read-only sections (such as ".text").
1925 This can be a significant performance improvement on some
1926 (notably embedded) targets.
1928 * New command "generate-core-file" (or "gcore").
1930 This new gdb command allows the user to drop a core file of the child
1931 process state at any time. So far it's been implemented only for
1932 GNU/Linux and Solaris, but should be relatively easily ported to other
1933 hosts. Argument is core file name (defaults to core.<pid>).
1935 * New command line option
1937 GDB now accepts --pid or -p followed by a process id.
1939 * Change in command line behavior -- corefiles vs. process ids.
1941 There is a subtle behavior in the way in which GDB handles
1942 command line arguments. The first non-flag argument is always
1943 a program to debug, but the second non-flag argument may either
1944 be a corefile or a process id. Previously, GDB would attempt to
1945 open the second argument as a corefile, and if that failed, would
1946 issue a superfluous error message and then attempt to attach it as
1947 a process. Now, if the second argument begins with a non-digit,
1948 it will be treated as a corefile. If it begins with a digit,
1949 GDB will attempt to attach it as a process, and if no such process
1950 is found, will then attempt to open it as a corefile.
1952 * Changes in ARM configurations.
1954 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1955 configuration is fully multi-arch.
1957 * New native configurations
1959 ARM NetBSD arm*-*-netbsd*
1960 x86 OpenBSD i[3456]86-*-openbsd*
1961 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1962 Sparc64 running FreeBSD sparc64-*-freebsd*
1966 Sanyo XStormy16 xstormy16-elf
1968 * OBSOLETE configurations and files
1970 Configurations that have been declared obsolete in this release have
1971 been commented out. Unless there is activity to revive these
1972 configurations, the next release of GDB will have their sources
1973 permanently REMOVED.
1975 AMD 29k family via UDI a29k-amd-udi, udi29k
1976 A29K VxWorks a29k-*-vxworks
1977 AMD 29000 embedded, using EBMON a29k-none-none
1978 AMD 29000 embedded with COFF a29k-none-coff
1979 AMD 29000 embedded with a.out a29k-none-aout
1981 testsuite/gdb.hp/gdb.threads-hp/ directory
1983 * REMOVED configurations and files
1985 TI TMS320C80 tic80-*-*
1987 PowerPC Solaris powerpcle-*-solaris*
1988 PowerPC Windows NT powerpcle-*-cygwin32
1989 PowerPC Netware powerpc-*-netware*
1990 Harris/CXUX m88k m88*-harris-cxux*
1991 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1992 ns32k-utek-sysv* ns32k-utek-*
1993 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1994 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1995 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1996 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1997 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1999 * Changes to command line processing
2001 The new `--args' feature can be used to specify command-line arguments
2002 for the inferior from gdb's command line.
2004 * Changes to key bindings
2006 There is a new `operate-and-get-next' function bound to `C-o'.
2008 *** Changes in GDB 5.1.1
2010 Fix compile problem on DJGPP.
2012 Fix a problem with floating-point registers on the i386 being
2015 Fix to stop GDB crashing on .debug_str debug info.
2017 Numerous documentation fixes.
2019 Numerous testsuite fixes.
2021 *** Changes in GDB 5.1:
2023 * New native configurations
2025 Alpha FreeBSD alpha*-*-freebsd*
2026 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2027 MIPS GNU/Linux mips*-*-linux*
2028 MIPS SGI Irix 6.x mips*-sgi-irix6*
2029 ia64 AIX ia64-*-aix*
2030 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2034 Motorola 68HC11 and 68HC12 m68hc11-elf
2036 UltraSparc running GNU/Linux sparc64-*-linux*
2038 * OBSOLETE configurations and files
2040 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2041 Harris/CXUX m88k m88*-harris-cxux*
2042 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2043 ns32k-utek-sysv* ns32k-utek-*
2044 TI TMS320C80 tic80-*-*
2046 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2047 PowerPC Solaris powerpcle-*-solaris*
2048 PowerPC Windows NT powerpcle-*-cygwin32
2049 PowerPC Netware powerpc-*-netware*
2050 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2051 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2052 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2053 Apple Macintosh (MPW) host N/A
2055 stuff.c (Program to stuff files into a specially prepared space in kdb)
2056 kdb-start.c (Main loop for the standalone kernel debugger)
2058 Configurations that have been declared obsolete in this release have
2059 been commented out. Unless there is activity to revive these
2060 configurations, the next release of GDB will have their sources
2061 permanently REMOVED.
2063 * REMOVED configurations and files
2065 Altos 3068 m68*-altos-*
2066 Convex c1-*-*, c2-*-*
2068 ARM RISCix arm-*-* (as host)
2072 * GDB has been converted to ISO C.
2074 GDB's source code has been converted to ISO C. In particular, the
2075 sources are fully protoized, and rely on standard headers being
2080 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2082 * The MI enabled by default.
2084 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2085 revised and enabled by default. Packages which use GDB as a debugging
2086 engine behind a UI or another front end are encouraged to switch to
2087 using the GDB/MI interface, instead of the old annotations interface
2088 which is now deprecated.
2090 * Support for debugging Pascal programs.
2092 GDB now includes support for debugging Pascal programs. The following
2093 main features are supported:
2095 - Pascal-specific data types such as sets;
2097 - automatic recognition of Pascal sources based on file-name
2100 - Pascal-style display of data types, variables, and functions;
2102 - a Pascal expression parser.
2104 However, some important features are not yet supported.
2106 - Pascal string operations are not supported at all;
2108 - there are some problems with boolean types;
2110 - Pascal type hexadecimal constants are not supported
2111 because they conflict with the internal variables format;
2113 - support for Pascal objects and classes is not full yet;
2115 - unlike Pascal, GDB is case-sensitive for symbol names.
2117 * Changes in completion.
2119 Commands such as `shell', `run' and `set args', which pass arguments
2120 to inferior programs, now complete on file names, similar to what
2121 users expect at the shell prompt.
2123 Commands which accept locations, such as `disassemble', `print',
2124 `breakpoint', `until', etc. now complete on filenames as well as
2125 program symbols. Thus, if you type "break foob TAB", and the source
2126 files linked into the programs include `foobar.c', that file name will
2127 be one of the candidates for completion. However, file names are not
2128 considered for completion after you typed a colon that delimits a file
2129 name from a name of a function in that file, as in "break foo.c:bar".
2131 `set demangle-style' completes on available demangling styles.
2133 * New platform-independent commands:
2135 It is now possible to define a post-hook for a command as well as a
2136 hook that runs before the command. For more details, see the
2137 documentation of `hookpost' in the GDB manual.
2139 * Changes in GNU/Linux native debugging.
2141 Support for debugging multi-threaded programs has been completely
2142 revised for all platforms except m68k and sparc. You can now debug as
2143 many threads as your system allows you to have.
2145 Attach/detach is supported for multi-threaded programs.
2147 Support for SSE registers was added for x86. This doesn't work for
2148 multi-threaded programs though.
2150 * Changes in MIPS configurations.
2152 Multi-arch support is enabled for all MIPS configurations.
2154 GDB can now be built as native debugger on SGI Irix 6.x systems for
2155 debugging n32 executables. (Debugging 64-bit executables is not yet
2158 * Unified support for hardware watchpoints in all x86 configurations.
2160 Most (if not all) native x86 configurations support hardware-assisted
2161 breakpoints and watchpoints in a unified manner. This support
2162 implements debug register sharing between watchpoints, which allows to
2163 put a virtually infinite number of watchpoints on the same address,
2164 and also supports watching regions up to 16 bytes with several debug
2167 The new maintenance command `maintenance show-debug-regs' toggles
2168 debugging print-outs in functions that insert, remove, and test
2169 watchpoints and hardware breakpoints.
2171 * Changes in the DJGPP native configuration.
2173 New command ``info dos sysinfo'' displays assorted information about
2174 the CPU, OS, memory, and DPMI server.
2176 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2177 display information about segment descriptors stored in GDT, LDT, and
2180 New commands ``info dos pde'' and ``info dos pte'' display entries
2181 from Page Directory and Page Tables (for now works with CWSDPMI only).
2182 New command ``info dos address-pte'' displays the Page Table entry for
2183 a given linear address.
2185 GDB can now pass command lines longer than 126 characters to the
2186 program being debugged (requires an update to the libdbg.a library
2187 which is part of the DJGPP development kit).
2189 DWARF2 debug info is now supported.
2191 It is now possible to `step' and `next' through calls to `longjmp'.
2193 * Changes in documentation.
2195 All GDB documentation was converted to GFDL, the GNU Free
2196 Documentation License.
2198 Tracepoints-related commands are now fully documented in the GDB
2201 TUI, the Text-mode User Interface, is now documented in the manual.
2203 Tracepoints-related commands are now fully documented in the GDB
2206 The "GDB Internals" manual now has an index. It also includes
2207 documentation of `ui_out' functions, GDB coding standards, x86
2208 hardware watchpoints, and memory region attributes.
2210 * GDB's version number moved to ``version.in''
2212 The Makefile variable VERSION has been replaced by the file
2213 ``version.in''. People creating GDB distributions should update the
2214 contents of this file.
2218 GUD support is now a standard part of the EMACS distribution.
2220 *** Changes in GDB 5.0:
2222 * Improved support for debugging FP programs on x86 targets
2224 Unified and much-improved support for debugging floating-point
2225 programs on all x86 targets. In particular, ``info float'' now
2226 displays the FP registers in the same format on all x86 targets, with
2227 greater level of detail.
2229 * Improvements and bugfixes in hardware-assisted watchpoints
2231 It is now possible to watch array elements, struct members, and
2232 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2233 on x86 targets no longer erroneously trigger when the address is
2236 * Improvements in the native DJGPP version of GDB
2238 The distribution now includes all the scripts and auxiliary files
2239 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2240 machines ``out of the box''.
2242 The DJGPP version can now debug programs that use signals. It is
2243 possible to catch signals that happened in the debuggee, deliver
2244 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2245 would kill the program being debugged.) Programs that hook hardware
2246 interrupts (keyboard, timer, etc.) can also be debugged.
2248 It is now possible to debug DJGPP programs that redirect their
2249 standard handles or switch them to raw (as opposed to cooked) mode, or
2250 even close them. The command ``run < foo > bar'' works as expected,
2251 and ``info terminal'' reports useful information about the debuggee's
2252 terminal, including raw/cooked mode, redirection, etc.
2254 The DJGPP version now uses termios functions for console I/O, which
2255 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2258 DOS-style file names with drive letters are now fully supported by
2261 It is now possible to debug DJGPP programs that switch their working
2262 directory. It is also possible to rerun the debuggee any number of
2263 times without restarting GDB; thus, you can use the same setup,
2264 breakpoints, etc. for many debugging sessions.
2266 * New native configurations
2268 ARM GNU/Linux arm*-*-linux*
2269 PowerPC GNU/Linux powerpc-*-linux*
2273 Motorola MCore mcore-*-*
2274 x86 VxWorks i[3456]86-*-vxworks*
2275 PowerPC VxWorks powerpc-*-vxworks*
2276 TI TMS320C80 tic80-*-*
2278 * OBSOLETE configurations
2280 Altos 3068 m68*-altos-*
2281 Convex c1-*-*, c2-*-*
2283 ARM RISCix arm-*-* (as host)
2286 Configurations that have been declared obsolete will be commented out,
2287 but the code will be left in place. If there is no activity to revive
2288 these configurations before the next release of GDB, the sources will
2289 be permanently REMOVED.
2291 * Gould support removed
2293 Support for the Gould PowerNode and NP1 has been removed.
2295 * New features for SVR4
2297 On SVR4 native platforms (such as Solaris), if you attach to a process
2298 without first loading a symbol file, GDB will now attempt to locate and
2299 load symbols from the running process's executable file.
2301 * Many C++ enhancements
2303 C++ support has been greatly improved. Overload resolution now works properly
2304 in almost all cases. RTTI support is on the way.
2306 * Remote targets can connect to a sub-program
2308 A popen(3) style serial-device has been added. This device starts a
2309 sub-process (such as a stand-alone simulator) and then communicates
2310 with that. The sub-program to run is specified using the syntax
2311 ``|<program> <args>'' vis:
2313 (gdb) set remotedebug 1
2314 (gdb) target extended-remote |mn10300-elf-sim program-args
2316 * MIPS 64 remote protocol
2318 A long standing bug in the mips64 remote protocol where by GDB
2319 expected certain 32 bit registers (ex SR) to be transfered as 32
2320 instead of 64 bits has been fixed.
2322 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2323 added to provide backward compatibility with older versions of GDB.
2325 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2327 The command ``set remotebinarydownload'' command has been replaced by
2328 ``set remote X-packet''. Other commands in ``set remote'' family
2329 include ``set remote P-packet''.
2331 * Breakpoint commands accept ranges.
2333 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2334 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2335 ``tracepoint passcount'' also accepts a range of tracepoints.
2337 * ``apropos'' command added.
2339 The ``apropos'' command searches through command names and
2340 documentation strings, printing out matches, making it much easier to
2341 try to find a command that does what you are looking for.
2345 A new machine oriented interface (MI) has been added to GDB. This
2346 interface is designed for debug environments running GDB as a separate
2347 process. This is part of the long term libGDB project. See the
2348 "GDB/MI" chapter of the GDB manual for further information. It can be
2349 enabled by configuring with:
2351 .../configure --enable-gdbmi
2353 *** Changes in GDB-4.18:
2355 * New native configurations
2357 HP-UX 10.20 hppa*-*-hpux10.20
2358 HP-UX 11.x hppa*-*-hpux11.0*
2359 M68K GNU/Linux m68*-*-linux*
2363 Fujitsu FR30 fr30-*-elf*
2364 Intel StrongARM strongarm-*-*
2365 Mitsubishi D30V d30v-*-*
2367 * OBSOLETE configurations
2369 Gould PowerNode, NP1 np1-*-*, pn-*-*
2371 Configurations that have been declared obsolete will be commented out,
2372 but the code will be left in place. If there is no activity to revive
2373 these configurations before the next release of GDB, the sources will
2374 be permanently REMOVED.
2378 As a compatibility experiment, GDB's source files buildsym.h and
2379 buildsym.c have been converted to pure standard C, no longer
2380 containing any K&R compatibility code. We believe that all systems in
2381 use today either come with a standard C compiler, or have a GCC port
2382 available. If this is not true, please report the affected
2383 configuration to bug-gdb@gnu.org immediately. See the README file for
2384 information about getting a standard C compiler if you don't have one
2389 GDB now uses readline 2.2.
2391 * set extension-language
2393 You can now control the mapping between filename extensions and source
2394 languages by using the `set extension-language' command. For instance,
2395 you can ask GDB to treat .c files as C++ by saying
2396 set extension-language .c c++
2397 The command `info extensions' lists all of the recognized extensions
2398 and their associated languages.
2400 * Setting processor type for PowerPC and RS/6000
2402 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2403 you can use the `set processor' command to specify what variant of the
2404 PowerPC family you are debugging. The command
2408 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2409 following PowerPC and RS6000 variants:
2411 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2412 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2414 403GC IBM PowerPC 403GC
2415 505 Motorola PowerPC 505
2416 860 Motorola PowerPC 860 or 850
2417 601 Motorola PowerPC 601
2418 602 Motorola PowerPC 602
2419 603 Motorola/IBM PowerPC 603 or 603e
2420 604 Motorola PowerPC 604 or 604e
2421 750 Motorola/IBM PowerPC 750 or 750
2423 At the moment, this command just tells GDB what to name the
2424 special-purpose processor registers. Since almost all the affected
2425 registers are inaccessible to user-level programs, this command is
2426 only useful for remote debugging in its present form.
2430 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2431 more extensive support for HP-UX. Added features include shared
2432 library support, kernel threads and hardware watchpoints for 11.00,
2433 support for HP's ANSI C and C++ compilers, and a compatibility mode
2434 for xdb and dbx commands.
2438 HP's donation includes the new concept of catchpoints, which is a
2439 generalization of the old catch command. On HP-UX, it is now possible
2440 to catch exec, fork, and vfork, as well as library loading.
2442 This means that the existing catch command has changed; its first
2443 argument now specifies the type of catch to be set up. See the
2444 output of "help catch" for a list of catchpoint types.
2446 * Debugging across forks
2448 On HP-UX, you can choose which process to debug when a fork() happens
2453 HP has donated a curses-based terminal user interface (TUI). To get
2454 it, build with --enable-tui. Although this can be enabled for any
2455 configuration, at present it only works for native HP debugging.
2457 * GDB remote protocol additions
2459 A new protocol packet 'X' that writes binary data is now available.
2460 Default behavior is to try 'X', then drop back to 'M' if the stub
2461 fails to respond. The settable variable `remotebinarydownload'
2462 allows explicit control over the use of 'X'.
2464 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2465 full 64-bit address. The command
2467 set remoteaddresssize 32
2469 can be used to revert to the old behaviour. For existing remote stubs
2470 the change should not be noticed, as the additional address information
2473 In order to assist in debugging stubs, you may use the maintenance
2474 command `packet' to send any text string to the stub. For instance,
2476 maint packet heythere
2478 sends the packet "$heythere#<checksum>". Note that it is very easy to
2479 disrupt a debugging session by sending the wrong packet at the wrong
2482 The compare-sections command allows you to compare section data on the
2483 target to what is in the executable file without uploading or
2484 downloading, by comparing CRC checksums.
2486 * Tracing can collect general expressions
2488 You may now collect general expressions at tracepoints. This requires
2489 further additions to the target-side stub; see tracepoint.c and
2490 doc/agentexpr.texi for further details.
2492 * mask-address variable for Mips
2494 For Mips targets, you may control the zeroing of the upper 32 bits of
2495 a 64-bit address by entering `set mask-address on'. This is mainly
2496 of interest to users of embedded R4xxx and R5xxx processors.
2498 * Higher serial baud rates
2500 GDB's serial code now allows you to specify baud rates 57600, 115200,
2501 230400, and 460800 baud. (Note that your host system may not be able
2502 to achieve all of these rates.)
2506 The i960 configuration now includes an initial implementation of a
2507 builtin simulator, contributed by Jim Wilson.
2510 *** Changes in GDB-4.17:
2512 * New native configurations
2514 Alpha GNU/Linux alpha*-*-linux*
2515 Unixware 2.x i[3456]86-unixware2*
2516 Irix 6.x mips*-sgi-irix6*
2517 PowerPC GNU/Linux powerpc-*-linux*
2518 PowerPC Solaris powerpcle-*-solaris*
2519 Sparc GNU/Linux sparc-*-linux*
2520 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2524 Argonaut Risc Chip (ARC) arc-*-*
2525 Hitachi H8/300S h8300*-*-*
2526 Matsushita MN10200 w/simulator mn10200-*-*
2527 Matsushita MN10300 w/simulator mn10300-*-*
2528 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2529 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2530 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2531 Mitsubishi D10V w/simulator d10v-*-*
2532 Mitsubishi M32R/D w/simulator m32r-*-elf*
2533 Tsqware Sparclet sparclet-*-*
2534 NEC V850 w/simulator v850-*-*
2536 * New debugging protocols
2538 ARM with RDI protocol arm*-*-*
2539 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2540 DDB and LSI variants of PMON protocol mips*-*-*
2541 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2542 PowerPC with SDS protocol powerpc{,le}-*-eabi
2543 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2547 All configurations can now understand and use the DWARF 2 debugging
2548 format. The choice is automatic, if the symbol file contains DWARF 2
2553 GDB now includes basic Java language support. This support is
2554 only useful with Java compilers that produce native machine code.
2556 * solib-absolute-prefix and solib-search-path
2558 For SunOS and SVR4 shared libraries, you may now set the prefix for
2559 loading absolute shared library symbol files, and the search path for
2560 locating non-absolute shared library symbol files.
2562 * Live range splitting
2564 GDB can now effectively debug code for which GCC has performed live
2565 range splitting as part of its optimization. See gdb/doc/LRS for
2566 more details on the expected format of the stabs information.
2570 GDB's support for the GNU Hurd, including thread debugging, has been
2571 updated to work with current versions of the Hurd.
2575 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2576 instruction set. ARM GDB automatically detects when Thumb
2577 instructions are in use, and adjusts disassembly and backtracing
2582 GDB's MIPS target configurations now handle the MIP16 16-bit
2587 GDB now includes support for overlays; if an executable has been
2588 linked such that multiple sections are based at the same address, GDB
2589 will decide which section to use for symbolic info. You can choose to
2590 control the decision manually, using overlay commands, or implement
2591 additional target-side support and use "overlay load-target" to bring
2592 in the overlay mapping. Do "help overlay" for more detail.
2596 The command "info symbol <address>" displays information about
2597 the symbol at the specified address.
2601 The standard remote protocol now includes an extension that allows
2602 asynchronous collection and display of trace data. This requires
2603 extensive support in the target-side debugging stub. Tracing mode
2604 includes a new interaction mode in GDB and new commands: see the
2605 file tracepoint.c for more details.
2609 Configurations for embedded MIPS now include a simulator contributed
2610 by Cygnus Solutions. The simulator supports the instruction sets
2611 of most MIPS variants.
2615 Sparc configurations may now include the ERC32 simulator contributed
2616 by the European Space Agency. The simulator is not built into
2617 Sparc targets by default; configure with --enable-sim to include it.
2621 For target configurations that may include multiple variants of a
2622 basic architecture (such as MIPS and SH), you may now set the
2623 architecture explicitly. "set arch" sets, "info arch" lists
2624 the possible architectures.
2626 *** Changes in GDB-4.16:
2628 * New native configurations
2630 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2631 M68K NetBSD m68k-*-netbsd*
2632 PowerPC AIX 4.x powerpc-*-aix*
2633 PowerPC MacOS powerpc-*-macos*
2634 PowerPC Windows NT powerpcle-*-cygwin32
2635 RS/6000 AIX 4.x rs6000-*-aix4*
2639 ARM with RDP protocol arm-*-*
2640 I960 with MON960 i960-*-coff
2641 MIPS VxWorks mips*-*-vxworks*
2642 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2643 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2645 Matra Sparclet sparclet-*-*
2649 The powerpc-eabi configuration now includes the PSIM simulator,
2650 contributed by Andrew Cagney, with assistance from Mike Meissner.
2651 PSIM is a very elaborate model of the PowerPC, including not only
2652 basic instruction set execution, but also details of execution unit
2653 performance and I/O hardware. See sim/ppc/README for more details.
2657 GDB now works with Solaris 2.5.
2659 * Windows 95/NT native
2661 GDB will now work as a native debugger on Windows 95 and Windows NT.
2662 To build it from source, you must use the "gnu-win32" environment,
2663 which uses a DLL to emulate enough of Unix to run the GNU tools.
2664 Further information, binaries, and sources are available at
2665 ftp.cygnus.com, under pub/gnu-win32.
2667 * dont-repeat command
2669 If a user-defined command includes the command `dont-repeat', then the
2670 command will not be repeated if the user just types return. This is
2671 useful if the command is time-consuming to run, so that accidental
2672 extra keystrokes don't run the same command many times.
2674 * Send break instead of ^C
2676 The standard remote protocol now includes an option to send a break
2677 rather than a ^C to the target in order to interrupt it. By default,
2678 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2680 * Remote protocol timeout
2682 The standard remote protocol includes a new variable `remotetimeout'
2683 that allows you to set the number of seconds before GDB gives up trying
2684 to read from the target. The default value is 2.
2686 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2688 By default GDB will automatically keep track of objects as they are
2689 loaded and unloaded by the dynamic linker. By using the command `set
2690 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2691 when shared library events occur, thus allowing you to set breakpoints
2692 in shared libraries which are explicitly loaded by the inferior.
2694 Note this feature does not work on hpux8. On hpux9 you must link
2695 /usr/lib/end.o into your program. This feature should work
2696 automatically on hpux10.
2698 * Irix 5.x hardware watchpoint support
2700 Irix 5 configurations now support the use of hardware watchpoints.
2702 * Mips protocol "SYN garbage limit"
2704 When debugging a Mips target using the `target mips' protocol, you
2705 may set the number of characters that GDB will ignore by setting
2706 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2707 every character. The default value is 1050.
2709 * Recording and replaying remote debug sessions
2711 If you set `remotelogfile' to the name of a file, gdb will write to it
2712 a recording of a remote debug session. This recording may then be
2713 replayed back to gdb using "gdbreplay". See gdbserver/README for
2714 details. This is useful when you have a problem with GDB while doing
2715 remote debugging; you can make a recording of the session and send it
2716 to someone else, who can then recreate the problem.
2718 * Speedups for remote debugging
2720 GDB includes speedups for downloading and stepping MIPS systems using
2721 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2722 and more efficient S-record downloading.
2724 * Memory use reductions and statistics collection
2726 GDB now uses less memory and reports statistics about memory usage.
2727 Try the `maint print statistics' command, for example.
2729 *** Changes in GDB-4.15:
2731 * Psymtabs for XCOFF
2733 The symbol reader for AIX GDB now uses partial symbol tables. This
2734 can greatly improve startup time, especially for large executables.
2736 * Remote targets use caching
2738 Remote targets now use a data cache to speed up communication with the
2739 remote side. The data cache could lead to incorrect results because
2740 it doesn't know about volatile variables, thus making it impossible to
2741 debug targets which use memory mapped I/O devices. `set remotecache
2742 off' turns the the data cache off.
2744 * Remote targets may have threads
2746 The standard remote protocol now includes support for multiple threads
2747 in the target system, using new protocol commands 'H' and 'T'. See
2748 gdb/remote.c for details.
2752 If GDB is configured with `--enable-netrom', then it will include
2753 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2754 acts as though it is a bank of ROM on the target board, but you can
2755 write into it over the network. GDB's support consists only of
2756 support for fast loading into the emulated ROM; to debug, you must use
2757 another protocol, such as standard remote protocol. The usual
2758 sequence is something like
2760 target nrom <netrom-hostname>
2762 target remote <netrom-hostname>:1235
2766 GDB now includes support for the Apple Macintosh, as a host only. It
2767 may be run as either an MPW tool or as a standalone application, and
2768 it can debug through the serial port. All the usual GDB commands are
2769 available, but to the target command, you must supply "serial" as the
2770 device type instead of "/dev/ttyXX". See mpw-README in the main
2771 directory for more information on how to build. The MPW configuration
2772 scripts */mpw-config.in support only a few targets, and only the
2773 mips-idt-ecoff target has been tested.
2777 GDB configuration now uses autoconf. This is not user-visible,
2778 but does simplify configuration and building.
2782 GDB now supports hpux10.
2784 *** Changes in GDB-4.14:
2786 * New native configurations
2788 x86 FreeBSD i[345]86-*-freebsd
2789 x86 NetBSD i[345]86-*-netbsd
2790 NS32k NetBSD ns32k-*-netbsd
2791 Sparc NetBSD sparc-*-netbsd
2795 A29K VxWorks a29k-*-vxworks
2796 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2797 CPU32 EST-300 emulator m68*-*-est*
2798 PowerPC ELF powerpc-*-elf
2801 * Alpha OSF/1 support for procfs
2803 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2804 possible to attach to running processes. As the mounting of the /proc
2805 filesystem is optional on the Alpha, GDB automatically determines
2806 the availability of /proc during startup. This can lead to problems
2807 if /proc is unmounted after GDB has been started.
2809 * Arguments to user-defined commands
2811 User commands may accept up to 10 arguments separated by whitespace.
2812 Arguments are accessed within the user command via $arg0..$arg9. A
2815 print $arg0 + $arg1 + $arg2
2817 To execute the command use:
2820 Defines the command "adder" which prints the sum of its three arguments.
2821 Note the arguments are text substitutions, so they may reference variables,
2822 use complex expressions, or even perform inferior function calls.
2824 * New `if' and `while' commands
2826 This makes it possible to write more sophisticated user-defined
2827 commands. Both commands take a single argument, which is the
2828 expression to evaluate, and must be followed by the commands to
2829 execute, one per line, if the expression is nonzero, the list being
2830 terminated by the word `end'. The `if' command list may include an
2831 `else' word, which causes the following commands to be executed only
2832 if the expression is zero.
2834 * Fortran source language mode
2836 GDB now includes partial support for Fortran 77. It will recognize
2837 Fortran programs and can evaluate a subset of Fortran expressions, but
2838 variables and functions may not be handled correctly. GDB will work
2839 with G77, but does not yet know much about symbols emitted by other
2842 * Better HPUX support
2844 Most debugging facilities now work on dynamic executables for HPPAs
2845 running hpux9 or later. You can attach to running dynamically linked
2846 processes, but by default the dynamic libraries will be read-only, so
2847 for instance you won't be able to put breakpoints in them. To change
2848 that behavior do the following before running the program:
2854 This will cause the libraries to be mapped private and read-write.
2855 To revert to the normal behavior, do this:
2861 You cannot set breakpoints or examine data in the library until after
2862 the library is loaded if the function/data symbols do not have
2865 GDB can now also read debug symbols produced by the HP C compiler on
2866 HPPAs (sorry, no C++, Fortran or 68k support).
2868 * Target byte order now dynamically selectable
2870 You can choose which byte order to use with a target system, via the
2871 commands "set endian big" and "set endian little", and you can see the
2872 current setting by using "show endian". You can also give the command
2873 "set endian auto", in which case GDB will use the byte order
2874 associated with the executable. Currently, only embedded MIPS
2875 configurations support dynamic selection of target byte order.
2877 * New DOS host serial code
2879 This version uses DPMI interrupts to handle buffered I/O, so you
2880 no longer need to run asynctsr when debugging boards connected to
2883 *** Changes in GDB-4.13:
2885 * New "complete" command
2887 This lists all the possible completions for the rest of the line, if it
2888 were to be given as a command itself. This is intended for use by emacs.
2890 * Trailing space optional in prompt
2892 "set prompt" no longer adds a space for you after the prompt you set. This
2893 allows you to set a prompt which ends in a space or one that does not.
2895 * Breakpoint hit counts
2897 "info break" now displays a count of the number of times the breakpoint
2898 has been hit. This is especially useful in conjunction with "ignore"; you
2899 can ignore a large number of breakpoint hits, look at the breakpoint info
2900 to see how many times the breakpoint was hit, then run again, ignoring one
2901 less than that number, and this will get you quickly to the last hit of
2904 * Ability to stop printing at NULL character
2906 "set print null-stop" will cause GDB to stop printing the characters of
2907 an array when the first NULL is encountered. This is useful when large
2908 arrays actually contain only short strings.
2910 * Shared library breakpoints
2912 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2913 breakpoints in shared libraries before the executable is run.
2915 * Hardware watchpoints
2917 There is a new hardware breakpoint for the watch command for sparclite
2918 targets. See gdb/sparclite/hw_breakpoint.note.
2920 Hardware watchpoints are also now supported under GNU/Linux.
2924 Annotations have been added. These are for use with graphical interfaces,
2925 and are still experimental. Currently only gdba.el uses these.
2927 * Improved Irix 5 support
2929 GDB now works properly with Irix 5.2.
2931 * Improved HPPA support
2933 GDB now works properly with the latest GCC and GAS.
2935 * New native configurations
2937 Sequent PTX4 i[34]86-sequent-ptx4
2938 HPPA running OSF/1 hppa*-*-osf*
2939 Atari TT running SVR4 m68*-*-sysv4*
2940 RS/6000 LynxOS rs6000-*-lynxos*
2944 OS/9000 i[34]86-*-os9k
2945 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2948 * Hitachi SH7000 and E7000-PC ICE support
2950 There is now support for communicating with the Hitachi E7000-PC ICE.
2951 This is available automatically when GDB is configured for the SH.
2955 As usual, a variety of small fixes and improvements, both generic
2956 and configuration-specific. See the ChangeLog for more detail.
2958 *** Changes in GDB-4.12:
2960 * Irix 5 is now supported
2964 GDB-4.12 on the HPPA has a number of changes which make it unable
2965 to debug the output from the currently released versions of GCC and
2966 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2967 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2968 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2971 *** Changes in GDB-4.11:
2973 * User visible changes:
2977 The "set remotedebug" option is now consistent between the mips remote
2978 target, remote targets using the gdb-specific protocol, UDI (AMD's
2979 debug protocol for the 29k) and the 88k bug monitor. It is now an
2980 integer specifying a debug level (normally 0 or 1, but 2 means more
2981 debugging info for the mips target).
2983 * DEC Alpha native support
2985 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2986 debug info, but GDB works fairly well with the DEC compiler and should
2987 work with a future GCC release. See the README file for a few
2988 Alpha-specific notes.
2990 * Preliminary thread implementation
2992 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2994 * LynxOS native and target support for 386
2996 This release has been hosted on LynxOS 2.2, and also can be configured
2997 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3000 * Improvements in C++ mangling/demangling.
3002 This release has much better g++ debugging, specifically in name
3003 mangling/demangling, virtual function calls, print virtual table,
3004 call methods, ...etc.
3006 *** Changes in GDB-4.10:
3008 * User visible changes:
3010 Remote debugging using the GDB-specific (`target remote') protocol now
3011 supports the `load' command. This is only useful if you have some
3012 other way of getting the stub to the target system, and you can put it
3013 somewhere in memory where it won't get clobbered by the download.
3015 Filename completion now works.
3017 When run under emacs mode, the "info line" command now causes the
3018 arrow to point to the line specified. Also, "info line" prints
3019 addresses in symbolic form (as well as hex).
3021 All vxworks based targets now support a user settable option, called
3022 vxworks-timeout. This option represents the number of seconds gdb
3023 should wait for responses to rpc's. You might want to use this if
3024 your vxworks target is, perhaps, a slow software simulator or happens
3025 to be on the far side of a thin network line.
3029 This release contains support for using a DEC alpha as a GDB host for
3030 cross debugging. Native alpha debugging is not supported yet.
3033 *** Changes in GDB-4.9:
3037 This is the first GDB release which is accompanied by a matching testsuite.
3038 The testsuite requires installation of dejagnu, which should be available
3039 via ftp from most sites that carry GNU software.
3043 'Cfront' style demangling has had its name changed to 'ARM' style, to
3044 emphasize that it was written from the specifications in the C++ Annotated
3045 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3046 disclaimers, it still generated too much confusion with users attempting to
3047 use gdb with AT&T cfront.
3051 GDB now uses a standard remote interface to a simulator library.
3052 So far, the library contains simulators for the Zilog Z8001/2, the
3053 Hitachi H8/300, H8/500 and Super-H.
3055 * New targets supported
3057 H8/300 simulator h8300-hitachi-hms or h8300hms
3058 H8/500 simulator h8500-hitachi-hms or h8500hms
3059 SH simulator sh-hitachi-hms or sh
3060 Z8000 simulator z8k-zilog-none or z8ksim
3061 IDT MIPS board over serial line mips-idt-ecoff
3063 Cross-debugging to GO32 targets is supported. It requires a custom
3064 version of the i386-stub.c module which is integrated with the
3065 GO32 memory extender.
3067 * New remote protocols
3069 MIPS remote debugging protocol.
3071 * New source languages supported
3073 This version includes preliminary support for Chill, a Pascal like language
3074 used by telecommunications companies. Chill support is also being integrated
3075 into the GNU compiler, but we don't know when it will be publically available.
3078 *** Changes in GDB-4.8:
3080 * HP Precision Architecture supported
3082 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3083 version of this support was available as a set of patches from the
3084 University of Utah. GDB does not support debugging of programs
3085 compiled with the HP compiler, because HP will not document their file
3086 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3087 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3089 Many problems in the preliminary version have been fixed.
3091 * Faster and better demangling
3093 We have improved template demangling and fixed numerous bugs in the GNU style
3094 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3095 character types (wchar_t) are now supported. Demangling of each symbol is now
3096 only done once, and is cached when the symbol table for a file is read in.
3097 This results in a small increase in memory usage for C programs, a moderate
3098 increase in memory usage for C++ programs, and a fantastic speedup in
3101 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3102 from the specifications in the Annotated Reference Manual, which AT&T's
3103 compiler does not actually implement.
3105 * G++ multiple inheritance compiler problem
3107 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3108 inheritance lattices was reworked to properly discover ambiguities. We
3109 recently found an example which causes this new algorithm to fail in a
3110 very subtle way, producing bad debug information for those classes.
3111 The file 'gcc.patch' (in this directory) can be applied to gcc to
3112 circumvent the problem. A future GCC release will contain a complete
3115 The previous G++ debug info problem (mentioned below for the gdb-4.7
3116 release) is fixed in gcc version 2.3.2.
3118 * Improved configure script
3120 The `configure' script will now attempt to guess your system type if
3121 you don't supply a host system type. The old scheme of supplying a
3122 host system triplet is preferable over using this. All the magic is
3123 done in the new `config.guess' script. Examine it for details.
3125 We have also brought our configure script much more in line with the FSF's
3126 version. It now supports the --with-xxx options. In particular,
3127 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3128 The resulting GDB will not be able to read arbitrary object file formats --
3129 only the format ``expected'' to be used on the configured target system.
3130 We hope to make this the default in a future release.
3132 * Documentation improvements
3134 There's new internal documentation on how to modify GDB, and how to
3135 produce clean changes to the code. We implore people to read it
3136 before submitting changes.
3138 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3139 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3140 `info' files are also provided. To build `info' files from scratch,
3141 you will need the latest `makeinfo' release, which will be available in
3142 a future texinfo-X.Y release.
3144 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3145 We're not sure exactly which versions have this problem, but it has
3146 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3147 or better. If that isn't possible, there is a patch in
3148 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3149 around this problem.
3153 GDB now supports array constants that can be used in expressions typed in by
3154 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3155 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3158 The new directory `gdb/sparclite' contains a program that demonstrates
3159 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3161 * New native hosts supported
3163 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3164 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3166 * New targets supported
3168 AMD 29k family via UDI a29k-amd-udi or udi29k
3170 * New file formats supported
3172 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3173 HPUX core files, and SCO 3.2v2 core files.
3177 Attaching to processes now works again; thanks for the many bug reports.
3179 We have also stomped on a bunch of core dumps caused by
3180 printf_filtered("%s") problems.
3182 We eliminated a copyright problem on the rpc and ptrace header files
3183 for VxWorks, which was discovered at the last minute during the 4.7
3184 release. You should now be able to build a VxWorks GDB.
3186 You can now interrupt gdb while an attached process is running. This
3187 will cause the attached process to stop, and give control back to GDB.
3189 We fixed problems caused by using too many file descriptors
3190 for reading symbols from object files and libraries. This was
3191 especially a problem for programs that used many (~100) shared
3194 The `step' command now only enters a subroutine if there is line number
3195 information for the subroutine. Otherwise it acts like the `next'
3196 command. Previously, `step' would enter subroutines if there was
3197 any debugging information about the routine. This avoids problems
3198 when using `cc -g1' on MIPS machines.
3200 * Internal improvements
3202 GDB's internal interfaces have been improved to make it easier to support
3203 debugging of multiple languages in the future.
3205 GDB now uses a common structure for symbol information internally.
3206 Minimal symbols (derived from linkage symbols in object files), partial
3207 symbols (from a quick scan of debug information), and full symbols
3208 contain a common subset of information, making it easier to write
3209 shared code that handles any of them.
3211 * New command line options
3213 We now accept --silent as an alias for --quiet.
3217 The memory-mapped-malloc library is now licensed under the GNU Library
3218 General Public License.
3220 *** Changes in GDB-4.7:
3222 * Host/native/target split
3224 GDB has had some major internal surgery to untangle the support for
3225 hosts and remote targets. Now, when you configure GDB for a remote
3226 target, it will no longer load in all of the support for debugging
3227 local programs on the host. When fully completed and tested, this will
3228 ensure that arbitrary host/target combinations are possible.
3230 The primary conceptual shift is to separate the non-portable code in
3231 GDB into three categories. Host specific code is required any time GDB
3232 is compiled on that host, regardless of the target. Target specific
3233 code relates to the peculiarities of the target, but can be compiled on
3234 any host. Native specific code is everything else: it can only be
3235 built when the host and target are the same system. Child process
3236 handling and core file support are two common `native' examples.
3238 GDB's use of /proc for controlling Unix child processes is now cleaner.
3239 It has been split out into a single module under the `target_ops' vector,
3240 plus two native-dependent functions for each system that uses /proc.
3242 * New hosts supported
3244 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3245 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3246 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3248 * New targets supported
3250 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3251 68030 and CPU32 m68030-*-*, m68332-*-*
3253 * New native hosts supported
3255 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3256 (386bsd is not well tested yet)
3257 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3259 * New file formats supported
3261 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3262 supports reading of `a.out.adobe' object files, which are an a.out
3263 format extended with minimal information about multiple sections.
3267 `show copying' is the same as the old `info copying'.
3268 `show warranty' is the same as `info warrantee'.
3269 These were renamed for consistency. The old commands continue to work.
3271 `info handle' is a new alias for `info signals'.
3273 You can now define pre-command hooks, which attach arbitrary command
3274 scripts to any command. The commands in the hook will be executed
3275 prior to the user's command. You can also create a hook which will be
3276 executed whenever the program stops. See gdb.texinfo.
3280 We now deal with Cfront style name mangling, and can even extract type
3281 info from mangled symbols. GDB can automatically figure out which
3282 symbol mangling style your C++ compiler uses.
3284 Calling of methods and virtual functions has been improved as well.
3288 The crash that occured when debugging Sun Ansi-C compiled binaries is
3289 fixed. This was due to mishandling of the extra N_SO stabs output
3292 We also finally got Ultrix 4.2 running in house, and fixed core file
3293 support, with help from a dozen people on the net.
3295 John M. Farrell discovered that the reason that single-stepping was so
3296 slow on all of the Mips based platforms (primarily SGI and DEC) was
3297 that we were trying to demangle and lookup a symbol used for internal
3298 purposes on every instruction that was being stepped through. Changing
3299 the name of that symbol so that it couldn't be mistaken for a C++
3300 mangled symbol sped things up a great deal.
3302 Rich Pixley sped up symbol lookups in general by getting much smarter
3303 about when C++ symbol mangling is necessary. This should make symbol
3304 completion (TAB on the command line) much faster. It's not as fast as
3305 we'd like, but it's significantly faster than gdb-4.6.
3309 A new user controllable variable 'call_scratch_address' can
3310 specify the location of a scratch area to be used when GDB
3311 calls a function in the target. This is necessary because the
3312 usual method of putting the scratch area on the stack does not work
3313 in systems that have separate instruction and data spaces.
3315 We integrated changes to support the 29k UDI (Universal Debugger
3316 Interface), but discovered at the last minute that we didn't have all
3317 of the appropriate copyright paperwork. We are working with AMD to
3318 resolve this, and hope to have it available soon.
3322 We have sped up the remote serial line protocol, especially for targets
3323 with lots of registers. It now supports a new `expedited status' ('T')
3324 message which can be used in place of the existing 'S' status message.
3325 This allows the remote stub to send only the registers that GDB
3326 needs to make a quick decision about single-stepping or conditional
3327 breakpoints, eliminating the need to fetch the entire register set for
3328 each instruction being stepped through.
3330 The GDB remote serial protocol now implements a write-through cache for
3331 registers, only re-reading the registers if the target has run.
3333 There is also a new remote serial stub for SPARC processors. You can
3334 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3335 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3336 processor with a serial port.
3340 Configure.in files have become much easier to read and modify. A new
3341 `table driven' format makes it more obvious what configurations are
3342 supported, and what files each one uses.
3346 There is a new opcodes library which will eventually contain all of the
3347 disassembly routines and opcode tables. At present, it only contains
3348 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3349 disassembler (binutils/objdump) to share these routines.
3351 The libiberty library is now copylefted under the GNU Library General
3352 Public License. This allows more liberal use, and was done so libg++
3353 can use it. This makes no difference to GDB, since the Library License
3354 grants all the rights from the General Public License.
3358 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3359 reference to the stabs symbol info used by the debugger. It is (as far
3360 as we know) the only published document on this fascinating topic. We
3361 encourage you to read it, compare it to the stabs information on your
3362 system, and send improvements on the document in general (to
3363 bug-gdb@prep.ai.mit.edu).
3365 And, of course, many bugs have been fixed.
3368 *** Changes in GDB-4.6:
3370 * Better support for C++ function names
3372 GDB now accepts as input the "demangled form" of C++ overloaded function
3373 names and member function names, and can do command completion on such names
3374 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3375 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3376 Make use of command completion, it is your friend.
3378 GDB also now accepts a variety of C++ mangled symbol formats. They are
3379 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3380 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3381 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3382 for the list of formats.
3384 * G++ symbol mangling problem
3386 Recent versions of gcc have a bug in how they emit debugging information for
3387 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3388 directory) can be applied to gcc to fix the problem. Alternatively, if you
3389 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3390 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3391 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3394 * New 'maintenance' command
3396 All of the commands related to hacking GDB internals have been moved out of
3397 the main command set, and now live behind the 'maintenance' command. This
3398 can also be abbreviated as 'mt'. The following changes were made:
3400 dump-me -> maintenance dump-me
3401 info all-breakpoints -> maintenance info breakpoints
3402 printmsyms -> maintenance print msyms
3403 printobjfiles -> maintenance print objfiles
3404 printpsyms -> maintenance print psymbols
3405 printsyms -> maintenance print symbols
3407 The following commands are new:
3409 maintenance demangle Call internal GDB demangler routine to
3410 demangle a C++ link name and prints the result.
3411 maintenance print type Print a type chain for a given symbol
3413 * Change to .gdbinit file processing
3415 We now read the $HOME/.gdbinit file before processing the argv arguments
3416 (e.g. reading symbol files or core files). This allows global parameters to
3417 be set, which will apply during the symbol reading. The ./.gdbinit is still
3418 read after argv processing.
3420 * New hosts supported
3422 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3424 GNU/Linux support i386-unknown-linux or linux
3426 We are also including code to support the HP/PA running BSD and HPUX. This
3427 is almost guaranteed not to work, as we didn't have time to test or build it
3428 for this release. We are including it so that the more adventurous (or
3429 masochistic) of you can play with it. We also had major problems with the
3430 fact that the compiler that we got from HP doesn't support the -g option.
3433 * New targets supported
3435 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3437 * More smarts about finding #include files
3439 GDB now remembers the compilation directory for all include files, and for
3440 all files from which C is generated (like yacc and lex sources). This
3441 greatly improves GDB's ability to find yacc/lex sources, and include files,
3442 especially if you are debugging your program from a directory different from
3443 the one that contains your sources.
3445 We also fixed a bug which caused difficulty with listing and setting
3446 breakpoints in include files which contain C code. (In the past, you had to
3447 try twice in order to list an include file that you hadn't looked at before.)
3449 * Interesting infernals change
3451 GDB now deals with arbitrary numbers of sections, where the symbols for each
3452 section must be relocated relative to that section's landing place in the
3453 target's address space. This work was needed to support ELF with embedded
3454 stabs used by Solaris-2.0.
3456 * Bug fixes (of course!)
3458 There have been loads of fixes for the following things:
3459 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3460 i960, stabs, DOS(GO32), procfs, etc...
3462 See the ChangeLog for details.
3464 *** Changes in GDB-4.5:
3466 * New machines supported (host and target)
3468 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3470 SGI Irix-4.x mips-sgi-irix4 or iris4
3472 * New malloc package
3474 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3475 Mmalloc is capable of handling mutiple heaps of memory. It is also
3476 capable of saving a heap to a file, and then mapping it back in later.
3477 This can be used to greatly speedup the startup of GDB by using a
3478 pre-parsed symbol table which lives in a mmalloc managed heap. For
3479 more details, please read mmalloc/mmalloc.texi.
3483 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3484 'help info proc' for details.
3486 * MIPS ecoff symbol table format
3488 The code that reads MIPS symbol table format is now supported on all hosts.
3489 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3492 * File name changes for MS-DOS
3494 Many files in the config directories have been renamed to make it easier to
3495 support GDB on MS-DOSe systems (which have very restrictive file name
3496 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3497 environment) is close to working but has some remaining problems. Note
3498 that debugging of DOS programs is not supported, due to limitations
3499 in the ``operating system'', but it can be used to host cross-debugging.
3501 * Cross byte order fixes
3503 Many fixes have been made to support cross debugging of Sparc and MIPS
3504 targets from hosts whose byte order differs.
3506 * New -mapped and -readnow options
3508 If memory-mapped files are available on your system through the 'mmap'
3509 system call, you can use the -mapped option on the `file' or
3510 `symbol-file' commands to cause GDB to write the symbols from your
3511 program into a reusable file. If the program you are debugging is
3512 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3513 Future GDB debugging sessions will notice the presence of this file,
3514 and will quickly map in symbol information from it, rather than reading
3515 the symbol table from the executable program. Using the '-mapped'
3516 option in a GDB `file' or `symbol-file' command has the same effect as
3517 starting GDB with the '-mapped' command-line option.
3519 You can cause GDB to read the entire symbol table immediately by using
3520 the '-readnow' option with any of the commands that load symbol table
3521 information (or on the GDB command line). This makes the command
3522 slower, but makes future operations faster.
3524 The -mapped and -readnow options are typically combined in order to
3525 build a `fred.syms' file that contains complete symbol information.
3526 A simple GDB invocation to do nothing but build a `.syms' file for future
3529 gdb -batch -nx -mapped -readnow programname
3531 The `.syms' file is specific to the host machine on which GDB is run.
3532 It holds an exact image of GDB's internal symbol table. It cannot be
3533 shared across multiple host platforms.
3535 * longjmp() handling
3537 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3538 siglongjmp() without losing control. This feature has not yet been ported to
3539 all systems. It currently works on many 386 platforms, all MIPS-based
3540 platforms (SGI, DECstation, etc), and Sun3/4.
3544 Preliminary work has been put in to support the new Solaris OS from Sun. At
3545 this time, it can control and debug processes, but it is not capable of
3550 As always, many many bug fixes. The major areas were with g++, and mipsread.
3551 People using the MIPS-based platforms should experience fewer mysterious
3552 crashes and trashed symbol tables.
3554 *** Changes in GDB-4.4:
3556 * New machines supported (host and target)
3558 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3560 BSD Reno on Vax vax-dec-bsd
3561 Ultrix on Vax vax-dec-ultrix
3563 * New machines supported (target)
3565 AMD 29000 embedded, using EBMON a29k-none-none
3569 GDB continues to improve its handling of C++. `References' work better.
3570 The demangler has also been improved, and now deals with symbols mangled as
3571 per the Annotated C++ Reference Guide.
3573 GDB also now handles `stabs' symbol information embedded in MIPS
3574 `ecoff' symbol tables. Since the ecoff format was not easily
3575 extensible to handle new languages such as C++, this appeared to be a
3576 good way to put C++ debugging info into MIPS binaries. This option
3577 will be supported in the GNU C compiler, version 2, when it is
3580 * New features for SVR4
3582 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3583 shared libraries. Debugging dynamically linked programs should present
3584 only minor differences from debugging statically linked programs.
3586 The `info proc' command will print out information about any process
3587 on an SVR4 system (including the one you are debugging). At the moment,
3588 it prints the address mappings of the process.
3590 If you bring up GDB on another SVR4 system, please send mail to
3591 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3593 * Better dynamic linking support in SunOS
3595 Reading symbols from shared libraries which contain debugging symbols
3596 now works properly. However, there remain issues such as automatic
3597 skipping of `transfer vector' code during function calls, which
3598 make it harder to debug code in a shared library, than to debug the
3599 same code linked statically.
3603 GDB is now using the latest `getopt' routines from the FSF. This
3604 version accepts the -- prefix for options with long names. GDB will
3605 continue to accept the old forms (-option and +option) as well.
3606 Various single letter abbreviations for options have been explicity
3607 added to the option table so that they won't get overshadowed in the
3608 future by other options that begin with the same letter.
3612 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3613 Many assorted bugs have been handled. Many more remain to be handled.
3614 See the various ChangeLog files (primarily in gdb and bfd) for details.
3617 *** Changes in GDB-4.3:
3619 * New machines supported (host and target)
3621 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3622 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3623 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3625 * Almost SCO Unix support
3627 We had hoped to support:
3628 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3629 (except for core file support), but we discovered very late in the release
3630 that it has problems with process groups that render gdb unusable. Sorry
3631 about that. I encourage people to fix it and post the fixes.
3633 * Preliminary ELF and DWARF support
3635 GDB can read ELF object files on System V Release 4, and can handle
3636 debugging records for C, in DWARF format, in ELF files. This support
3637 is preliminary. If you bring up GDB on another SVR4 system, please
3638 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3643 GDB now uses the latest `readline' library. One user-visible change
3644 is that two tabs will list possible command completions, which previously
3645 required typing M-? (meta-question mark, or ESC ?).
3649 The `stepi' bug that many of you noticed has been squashed.
3650 Many bugs in C++ have been handled. Many more remain to be handled.
3651 See the various ChangeLog files (primarily in gdb and bfd) for details.
3653 * State of the MIPS world (in case you wondered):
3655 GDB can understand the symbol tables emitted by the compilers
3656 supplied by most vendors of MIPS-based machines, including DEC. These
3657 symbol tables are in a format that essentially nobody else uses.
3659 Some versions of gcc come with an assembler post-processor called
3660 mips-tfile. This program is required if you want to do source-level
3661 debugging of gcc-compiled programs. I believe FSF does not ship
3662 mips-tfile with gcc version 1, but it will eventually come with gcc
3665 Debugging of g++ output remains a problem. g++ version 1.xx does not
3666 really support it at all. (If you're lucky, you should be able to get
3667 line numbers and stack traces to work, but no parameters or local
3668 variables.) With some work it should be possible to improve the
3671 When gcc version 2 is released, you will have somewhat better luck.
3672 However, even then you will get confusing results for inheritance and
3675 We will eventually provide full debugging of g++ output on
3676 DECstations. This will probably involve some kind of stabs-in-ecoff
3677 encapulation, but the details have not been worked out yet.
3680 *** Changes in GDB-4.2:
3682 * Improved configuration
3684 Only one copy of `configure' exists now, and it is not self-modifying.
3685 Porting BFD is simpler.
3689 The `step' and `next' commands now only stop at the first instruction
3690 of a source line. This prevents the multiple stops that used to occur
3691 in switch statements, for-loops, etc. `Step' continues to stop if a
3692 function that has debugging information is called within the line.
3696 Lots of small bugs fixed. More remain.
3698 * New host supported (not target)
3700 Intel 386 PC clone running Mach i386-none-mach
3703 *** Changes in GDB-4.1:
3705 * Multiple source language support
3707 GDB now has internal scaffolding to handle several source languages.
3708 It determines the type of each source file from its filename extension,
3709 and will switch expression parsing and number formatting to match the
3710 language of the function in the currently selected stack frame.
3711 You can also specifically set the language to be used, with
3712 `set language c' or `set language modula-2'.
3716 GDB now has preliminary support for the GNU Modula-2 compiler,
3717 currently under development at the State University of New York at
3718 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3719 continue through the fall of 1991 and into 1992.
3721 Other Modula-2 compilers are currently not supported, and attempting to
3722 debug programs compiled with them will likely result in an error as the
3723 symbol table is read. Feel free to work on it, though!
3725 There are hooks in GDB for strict type checking and range checking,
3726 in the `Modula-2 philosophy', but they do not currently work.
3730 GDB can now write to executable and core files (e.g. patch
3731 a variable's value). You must turn this switch on, specify
3732 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3733 by assigning a new value to a variable. Modifications take
3736 * Automatic SunOS shared library reading
3738 When you run your program, GDB automatically determines where its
3739 shared libraries (if any) have been loaded, and reads their symbols.
3740 The `share' command is no longer needed. This also works when
3741 examining core files.
3745 You can specify the number of lines that the `list' command shows.
3748 * New machines supported (host and target)
3750 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3751 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3752 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3754 * New hosts supported (not targets)
3756 IBM RT/PC: romp-ibm-aix or rtpc
3758 * New targets supported (not hosts)
3760 AMD 29000 embedded with COFF a29k-none-coff
3761 AMD 29000 embedded with a.out a29k-none-aout
3762 Ultracomputer remote kernel debug a29k-nyu-kern
3764 * New remote interfaces
3770 *** Changes in GDB-4.0:
3774 Wide output is wrapped at good places to make the output more readable.
3776 Gdb now supports cross-debugging from a host machine of one type to a
3777 target machine of another type. Communication with the target system
3778 is over serial lines. The ``target'' command handles connecting to the
3779 remote system; the ``load'' command will download a program into the
3780 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3781 also supports debugging of realtime processes running under VxWorks,
3782 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3783 stub on the target system.
3785 New CPUs supported include the AMD 29000 and Intel 960.
3787 GDB now reads object files and symbol tables via a ``binary file''
3788 library, which allows a single copy of GDB to debug programs of multiple
3789 object file types such as a.out and coff.
3791 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3792 refcard.dvi and refcard.ps are available to format it).
3795 * Control-Variable user interface simplified
3797 All variables that control the operation of the debugger can be set
3798 by the ``set'' command, and displayed by the ``show'' command.
3800 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3801 ``Show prompt'' produces the response:
3802 Gdb's prompt is new-gdb=>.
3804 What follows are the NEW set commands. The command ``help set'' will
3805 print a complete list of old and new set commands. ``help set FOO''
3806 will give a longer description of the variable FOO. ``show'' will show
3807 all of the variable descriptions and their current settings.
3809 confirm on/off: Enables warning questions for operations that are
3810 hard to recover from, e.g. rerunning the program while
3811 it is already running. Default is ON.
3813 editing on/off: Enables EMACS style command line editing
3814 of input. Previous lines can be recalled with
3815 control-P, the current line can be edited with control-B,
3816 you can search for commands with control-R, etc.
3819 history filename NAME: NAME is where the gdb command history
3820 will be stored. The default is .gdb_history,
3821 or the value of the environment variable
3824 history size N: The size, in commands, of the command history. The
3825 default is 256, or the value of the environment variable
3828 history save on/off: If this value is set to ON, the history file will
3829 be saved after exiting gdb. If set to OFF, the
3830 file will not be saved. The default is OFF.
3832 history expansion on/off: If this value is set to ON, then csh-like
3833 history expansion will be performed on
3834 command line input. The default is OFF.
3836 radix N: Sets the default radix for input and output. It can be set
3837 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3838 in the current radix, so "set radix 10" is always a no-op.
3840 height N: This integer value is the number of lines on a page. Default
3841 is 24, the current `stty rows'' setting, or the ``li#''
3842 setting from the termcap entry matching the environment
3845 width N: This integer value is the number of characters on a line.
3846 Default is 80, the current `stty cols'' setting, or the ``co#''
3847 setting from the termcap entry matching the environment
3850 Note: ``set screensize'' is obsolete. Use ``set height'' and
3851 ``set width'' instead.
3853 print address on/off: Print memory addresses in various command displays,
3854 such as stack traces and structure values. Gdb looks
3855 more ``symbolic'' if you turn this off; it looks more
3856 ``machine level'' with it on. Default is ON.
3858 print array on/off: Prettyprint arrays. New convenient format! Default
3861 print demangle on/off: Print C++ symbols in "source" form if on,
3864 print asm-demangle on/off: Same, for assembler level printouts
3867 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3870 * Support for Epoch Environment.
3872 The epoch environment is a version of Emacs v18 with windowing. One
3873 new command, ``inspect'', is identical to ``print'', except that if you
3874 are running in the epoch environment, the value is printed in its own
3878 * Support for Shared Libraries
3880 GDB can now debug programs and core files that use SunOS shared libraries.
3881 Symbols from a shared library cannot be referenced
3882 before the shared library has been linked with the program (this
3883 happens after you type ``run'' and before the function main() is entered).
3884 At any time after this linking (including when examining core files
3885 from dynamically linked programs), gdb reads the symbols from each
3886 shared library when you type the ``sharedlibrary'' command.
3887 It can be abbreviated ``share''.
3889 sharedlibrary REGEXP: Load shared object library symbols for files
3890 matching a unix regular expression. No argument
3891 indicates to load symbols for all shared libraries.
3893 info sharedlibrary: Status of loaded shared libraries.
3898 A watchpoint stops execution of a program whenever the value of an
3899 expression changes. Checking for this slows down execution
3900 tremendously whenever you are in the scope of the expression, but is
3901 quite useful for catching tough ``bit-spreader'' or pointer misuse
3902 problems. Some machines such as the 386 have hardware for doing this
3903 more quickly, and future versions of gdb will use this hardware.
3905 watch EXP: Set a watchpoint (breakpoint) for an expression.
3907 info watchpoints: Information about your watchpoints.
3909 delete N: Deletes watchpoint number N (same as breakpoints).
3910 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3911 enable N: Re-enables watchpoint number N (same as breakpoints).
3914 * C++ multiple inheritance
3916 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3919 * C++ exception handling
3921 Gdb now supports limited C++ exception handling. Besides the existing
3922 ability to breakpoint on an exception handler, gdb can breakpoint on
3923 the raising of an exception (before the stack is peeled back to the
3926 catch FOO: If there is a FOO exception handler in the dynamic scope,
3927 set a breakpoint to catch exceptions which may be raised there.
3928 Multiple exceptions (``catch foo bar baz'') may be caught.
3930 info catch: Lists all exceptions which may be caught in the
3931 current stack frame.
3934 * Minor command changes
3936 The command ``call func (arg, arg, ...)'' now acts like the print
3937 command, except it does not print or save a value if the function's result
3938 is void. This is similar to dbx usage.
3940 The ``up'' and ``down'' commands now always print the frame they end up
3941 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3942 frames without printing.
3944 * New directory command
3946 'dir' now adds directories to the FRONT of the source search path.
3947 The path starts off empty. Source files that contain debug information
3948 about the directory in which they were compiled can be found even
3949 with an empty path; Sun CC and GCC include this information. If GDB can't
3950 find your source file in the current directory, type "dir .".
3952 * Configuring GDB for compilation
3954 For normal use, type ``./configure host''. See README or gdb.texinfo
3957 GDB now handles cross debugging. If you are remotely debugging between
3958 two different machines, type ``./configure host -target=targ''.
3959 Host is the machine where GDB will run; targ is the machine
3960 where the program that you are debugging will run.