1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.0
8 GDB now supports importing of namespaces in C++. This enables the
9 user to inspect variables from imported namespaces. Support for
10 namepace aliasing has also been added. So, if a namespace is
11 aliased in the current scope (e.g. namepace C=A; ) the user can
12 print variables using the alias (e.g. (gdb) print C::x).
16 Xilinx MicroBlaze microblaze-*-*
21 Xilinx MicroBlaze microblaze
24 * Multi-program debugging.
26 GDB now has support for multi-program (a.k.a. multi-executable or
27 multi-exec) debugging. This allows for debugging multiple inferiors
28 simultaneously each running a different program under the same GDB
29 session. See "Debugging Multiple Inferiors and Programs" in the
30 manual for more information. This implied some user visible changes
31 in the multi-inferior support. For example, "info inferiors" now
32 lists inferiors that are not running yet or that have exited
33 already. See also "New commands" and "New options" below.
35 * New tracing features
37 GDB's tracepoint facility now includes several new features:
39 ** Trace state variables
41 GDB tracepoints now include support for trace state variables, which
42 are variables managed by the target agent during a tracing
43 experiment. They are useful for tracepoints that trigger each
44 other, so for instance one tracepoint can count hits in a variable,
45 and then a second tracepoint has a condition that is true when the
46 count reaches a particular value. Trace state variables share the
47 $-syntax of GDB convenience variables, and can appear in both
48 tracepoint actions and condition expressions. Use the "tvariable"
49 command to create, and "info tvariables" to view; see "Trace State
50 Variables" in the manual for more detail.
54 GDB now includes an option for defining fast tracepoints, which
55 targets may implement more efficiently, such as by installing a jump
56 into the target agent rather than a trap instruction. The resulting
57 speedup can be by two orders of magnitude or more, although the
58 tradeoff is that some program locations on some target architectures
59 might not allow fast tracepoint installation, for instance if the
60 instruction to be replaced is shorter than the jump. To request a
61 fast tracepoint, use the "ftrace" command, with syntax identical to
62 the regular trace command.
64 ** Disconnected tracing
66 It is now possible to detach GDB from the target while it is running
67 a trace experiment, then reconnect later to see how the experiment
68 is going. In addition, a new variable disconnected-tracing lets you
69 tell the target agent whether to continue running a trace if the
70 connection is lost unexpectedly.
74 GDB now has the ability to save the trace buffer into a file, and
75 then use that file as a target, similarly to you can do with
76 corefiles. You can select trace frames, print data that was
77 collected in them, and use tstatus to display the state of the
78 tracing run at the moment that it was saved. To create a trace
79 file, use "tsave <filename>", and to use it, do "target tfile
85 The disassemble command, when invoked with two arguments, now requires
86 the arguments to be comma-separated.
89 The info variables command now displays variable definitions. Files
90 which only declare a variable are not shown.
93 The source command is now capable of sourcing Python scripts.
94 This feature is dependent on the debugger being build with Python
97 Related to this enhancement is also the introduction of a new command
98 "set script-extension" (see below).
100 * New commands (for set/show, see "New options" below)
102 record save [<FILENAME>]
103 Save a file (in core file format) containing the process record
104 execution log for replay debugging at a later time.
106 record restore <FILENAME>
107 Restore the process record execution log that was saved at an
108 earlier time, for replay debugging.
110 add-inferior [-copies <N>] [-exec <FILENAME>]
113 clone-inferior [-copies <N>] [ID]
114 Make a new inferior ready to execute the same program another
120 maint info program-spaces
121 List the program spaces loaded into GDB.
123 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
124 show remote interrupt-sequence
125 Allow the user to select one of ^C, a BREAK signal or BREAK-g
126 as the sequence to the remote target in order to interrupt the execution.
127 Ctrl-C is a default. Some system prefers BREAK which is high level of
128 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
129 Magic SysRq g. It is BREAK signal and character 'g'.
131 set remote interrupt-on-connect [on | off]
132 show remote interrupt-on-connect
133 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
134 remote target when gdb connects to it. This is needed when you debug
137 set remotebreak [on | off]
139 Deprecated. Use "set/show remote interrupt-sequence" instead.
141 tvariable $NAME [ = EXP ]
142 Create or modify a trace state variable.
145 List trace state variables and their values.
147 delete tvariable $NAME ...
148 Delete one or more trace state variables.
151 Evaluate the given expressions without collecting anything into the
152 trace buffer. (Valid in tracepoint actions only.)
154 ftrace FN / FILE:LINE / *ADDR
155 Define a fast tracepoint at the given function, line, or address.
157 * New expression syntax
159 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
160 GDB now parses 0b101010 identically with 42.
164 set follow-exec-mode new|same
165 show follow-exec-mode
166 Control whether GDB reuses the same inferior across an exec call or
167 creates a new one. This is useful to be able to restart the old
168 executable after the inferior having done an exec call.
170 set default-collect EXPR, ...
172 Define a list of expressions to be collected at each tracepoint.
173 This is a useful way to ensure essential items are not overlooked,
174 such as registers or a critical global variable.
176 set disconnected-tracing
177 show disconnected-tracing
178 If set to 1, the target is instructed to continue tracing if it
179 loses its connection to GDB. If 0, the target is to stop tracing
182 set script-extension off|soft|strict
183 show script-extension
184 If set to "off", the debugger does not perform any script language
185 recognition, and all sourced files are assumed to be GDB scripts.
186 If set to "soft" (the default), files are sourced according to
187 filename extension, falling back to GDB scripts if the first
189 If set to "strict", files are sourced according to filename extension.
191 set ada trust-PAD-over-XVS on|off
192 show ada trust-PAD-over-XVS
193 If off, activate a workaround against a bug in the debugging information
194 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
195 the GCC sources for more information about the GNAT encoding and
196 PAD types in particular). It is always safe to set this option to
197 off, but this introduces a slight performance penalty. The default
203 Define a trace state variable.
206 Get the current value of a trace state variable.
209 Set desired tracing behavior upon disconnection.
212 Get data about the tracepoints currently in use.
216 Process record now works correctly with hardware watchpoints.
218 Multiple bug fixes have been made to the mips-irix port, making it
219 much more reliable. In particular:
220 - Debugging threaded applications is now possible again. Previously,
221 GDB would hang while starting the program, or while waiting for
222 the program to stop at a breakpoint.
223 - Attaching to a running process no longer hangs.
224 - An error occurring while loading a core file has been fixed.
225 - Changing the value of the PC register now works again. This fixes
226 problems observed when using the "jump" command, or when calling
227 a function from GDB, or even when assigning a new value to $pc.
228 - With the "finish" and "return" commands, the return value for functions
229 returning a small array is now correctly printed.
230 - It is now possible to break on shared library code which gets executed
231 during a shared library init phase (code executed while executing
232 their .init section). Previously, the breakpoint would have no effect.
233 - GDB is now able to backtrace through the signal handler for
234 non-threaded programs.
236 PIE (Position Independent Executable) programs debugging is now supported.
237 This includes debugging execution of PIC (Position Independent Code) shared
238 libraries although for that, it should be possible to run such libraries as an
241 *** Changes in GDB 7.0
243 * GDB now has an interface for JIT compilation. Applications that
244 dynamically generate code can create symbol files in memory and register
245 them with GDB. For users, the feature should work transparently, and
246 for JIT developers, the interface is documented in the GDB manual in the
247 "JIT Compilation Interface" chapter.
249 * Tracepoints may now be conditional. The syntax is as for
250 breakpoints; either an "if" clause appended to the "trace" command,
251 or the "condition" command is available. GDB sends the condition to
252 the target for evaluation using the same bytecode format as is used
253 for tracepoint actions.
255 * "disassemble" command with a /r modifier, print the raw instructions
256 in hex as well as in symbolic form."
258 * Process record and replay
260 In a architecture environment that supports ``process record and
261 replay'', ``process record and replay'' target can record a log of
262 the process execution, and replay it with both forward and reverse
265 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
266 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
267 set execution-direction {forward|reverse}, for targets that support
270 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
271 feature is available with a native GDB running on kernel version
274 * GDB now has support for multi-byte and wide character sets on the
275 target. Strings whose character type is wchar_t, char16_t, or
276 char32_t are now correctly printed. GDB supports wide- and unicode-
277 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
278 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
279 `printf'. This feature requires iconv to work properly; if your
280 system does not have a working iconv, GDB can use GNU libiconv. See
281 the installation instructions for more information.
283 * GDB now supports automatic retrieval of shared library files from
284 remote targets. To use this feature, specify a system root that begins
285 with the `remote:' prefix, either via the `set sysroot' command or via
286 the `--with-sysroot' configure-time option.
288 * "info sharedlibrary" now takes an optional regex of libraries to show,
289 and it now reports if a shared library has no debugging information.
291 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
292 now complete on file names.
294 * When completing in expressions, gdb will attempt to limit
295 completions to allowable structure or union fields, where appropriate.
296 For instance, consider:
298 # struct example { int f1; double f2; };
299 # struct example variable;
302 If the user types TAB at the end of this command line, the available
303 completions will be "f1" and "f2".
305 * Inlined functions are now supported. They show up in backtraces, and
306 the "step", "next", and "finish" commands handle them automatically.
308 * GDB now supports the token-splicing (##) and stringification (#)
309 operators when expanding macros. It also supports variable-arity
312 * GDB now supports inspecting extra signal information, exported by
313 the new $_siginfo convenience variable. The feature is currently
314 implemented on linux ARM, i386 and amd64.
316 * GDB can now display the VFP floating point registers and NEON vector
317 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
318 can provide these registers (requires Linux 2.6.30 or later). Remote
319 and simulator targets may also provide them.
324 Search memory for a sequence of bytes.
327 Turn off `+'/`-' protocol acknowledgments to permit more efficient
328 operation over reliable transport links. Use of this packet is
329 controlled by the `set remote noack-packet' command.
332 Kill the process with the specified process ID. Use this in preference
333 to `k' when multiprocess protocol extensions are supported.
336 Obtains additional operating system information
340 Read or write additional signal information.
342 * Removed remote protocol undocumented extension
344 An undocumented extension to the remote protocol's `S' stop reply
345 packet that permited the stub to pass a process id was removed.
346 Remote servers should use the `T' stop reply packet instead.
348 * The "disassemble" command now supports an optional /m modifier to print mixed
351 * GDB now supports multiple function calling conventions according to the
352 DWARF-2 DW_AT_calling_convention function attribute.
354 * The SH target utilizes the aforementioned change to distinguish between gcc
355 and Renesas calling convention. It also adds the new CLI commands
356 `set/show sh calling-convention'.
358 * GDB can now read compressed debug sections, as produced by GNU gold
359 with the --compress-debug-sections=zlib flag.
361 * 64-bit core files are now supported on AIX.
363 * Thread switching is now supported on Tru64.
365 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
366 which will be allocated using malloc later in program execution.
368 * The qXfer:libraries:read remote procotol packet now allows passing a
369 list of section offsets.
371 * On GNU/Linux, GDB can now attach to stopped processes. Several race
372 conditions handling signals delivered during attach or thread creation
373 have also been fixed.
375 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
376 From the user's standpoint, all unqualified instances of True and False
377 are treated as the standard definitions, regardless of context.
379 * GDB now parses C++ symbol and type names more flexibly. For
382 template<typename T> class C { };
385 GDB will now correctly handle all of:
387 ptype C<char const *>
389 ptype C<const char *>
392 * New features in the GDB remote stub, gdbserver
394 - The "--wrapper" command-line argument tells gdbserver to use a
395 wrapper program to launch programs for debugging.
397 - On PowerPC and S/390 targets, it is now possible to use a single
398 gdbserver executable to debug both 32-bit and 64-bit programs.
399 (This requires gdbserver itself to be built as a 64-bit executable.)
401 - gdbserver uses the new noack protocol mode for TCP connections to
402 reduce communications latency, if also supported and enabled in GDB.
404 - Support for the sparc64-linux-gnu target is now included in
407 - The amd64-linux build of gdbserver now supports debugging both
408 32-bit and 64-bit programs.
410 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
411 now support hardware watchpoints, and will use them automatically
416 GDB now has support for scripting using Python. Whether this is
417 available is determined at configure time.
419 New GDB commands can now be written in Python.
421 * Ada tasking support
423 Ada tasks can now be inspected in GDB. The following commands have
427 Print the list of Ada tasks.
429 Print detailed information about task number N.
431 Print the task number of the current task.
433 Switch the context of debugging to task number N.
435 * Support for user-defined prefixed commands. The "define" command can
436 add new commands to existing prefixes, e.g. "target".
438 * Multi-inferior, multi-process debugging.
440 GDB now has generalized support for multi-inferior debugging. See
441 "Debugging Multiple Inferiors" in the manual for more information.
442 Although availability still depends on target support, the command
443 set is more uniform now. The GNU/Linux specific multi-forks support
444 has been migrated to this new framework. This implied some user
445 visible changes; see "New commands" and also "Removed commands"
448 * Target descriptions can now describe the target OS ABI. See the
449 "Target Description Format" section in the user manual for more
452 * Target descriptions can now describe "compatible" architectures
453 to indicate that the target can execute applications for a different
454 architecture in addition to those for the main target architecture.
455 See the "Target Description Format" section in the user manual for
458 * Multi-architecture debugging.
460 GDB now includes general supports for debugging applications on
461 hybrid systems that use more than one single processor architecture
462 at the same time. Each such hybrid architecture still requires
463 specific support to be added. The only hybrid architecture supported
464 in this version of GDB is the Cell Broadband Engine.
466 * GDB now supports integrated debugging of Cell/B.E. applications that
467 use both the PPU and SPU architectures. To enable support for hybrid
468 Cell/B.E. debugging, you need to configure GDB to support both the
469 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
470 --enable-targets configure option.
472 * Non-stop mode debugging.
474 For some targets, GDB now supports an optional mode of operation in
475 which you can examine stopped threads while other threads continue
476 to execute freely. This is referred to as non-stop mode, with the
477 old mode referred to as all-stop mode. See the "Non-Stop Mode"
478 section in the user manual for more information.
480 To be able to support remote non-stop debugging, a remote stub needs
481 to implement the non-stop mode remote protocol extensions, as
482 described in the "Remote Non-Stop" section of the user manual. The
483 GDB remote stub, gdbserver, has been adjusted to support these
484 extensions on linux targets.
486 * New commands (for set/show, see "New options" below)
488 catch syscall [NAME(S) | NUMBER(S)]
489 Catch system calls. Arguments, which should be names of system
490 calls or their numbers, mean catch only those syscalls. Without
491 arguments, every syscall will be caught. When the inferior issues
492 any of the specified syscalls, GDB will stop and announce the system
493 call, both when it is called and when its call returns. This
494 feature is currently available with a native GDB running on the
495 Linux Kernel, under the following architectures: x86, x86_64,
496 PowerPC and PowerPC64.
498 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
500 Search memory for a sequence of bytes.
502 maint set python print-stack
503 maint show python print-stack
504 Show a stack trace when an error is encountered in a Python script.
507 Invoke CODE by passing it to the Python interpreter.
512 These allow macros to be defined, undefined, and listed
516 Show operating system information about processes.
519 List the inferiors currently under GDB's control.
522 Switch focus to inferior number NUM.
525 Detach from inferior number NUM.
528 Kill inferior number NUM.
533 show spu stop-on-load
534 Control whether to stop for new SPE threads during Cell/B.E. debugging.
536 set spu auto-flush-cache
537 show spu auto-flush-cache
538 Control whether to automatically flush the software-managed cache
539 during Cell/B.E. debugging.
541 set sh calling-convention
542 show sh calling-convention
543 Control the calling convention used when calling SH target functions.
547 Control display of timestamps with GDB debugging output.
549 set disassemble-next-line
550 show disassemble-next-line
551 Control display of disassembled source lines or instructions when
554 set remote noack-packet
555 show remote noack-packet
556 Set/show the use of remote protocol QStartNoAckMode packet. See above
557 under "New remote packets."
559 set remote query-attached-packet
560 show remote query-attached-packet
561 Control use of remote protocol `qAttached' (query-attached) packet.
563 set remote read-siginfo-object
564 show remote read-siginfo-object
565 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
568 set remote write-siginfo-object
569 show remote write-siginfo-object
570 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
573 set remote reverse-continue
574 show remote reverse-continue
575 Control use of remote protocol 'bc' (reverse-continue) packet.
577 set remote reverse-step
578 show remote reverse-step
579 Control use of remote protocol 'bs' (reverse-step) packet.
581 set displaced-stepping
582 show displaced-stepping
583 Control displaced stepping mode. Displaced stepping is a way to
584 single-step over breakpoints without removing them from the debuggee.
585 Also known as "out-of-line single-stepping".
589 Control display of debugging info for displaced stepping.
591 maint set internal-error
592 maint show internal-error
593 Control what GDB does when an internal error is detected.
595 maint set internal-warning
596 maint show internal-warning
597 Control what GDB does when an internal warning is detected.
602 Use a wrapper program to launch programs for debugging.
604 set multiple-symbols (all|ask|cancel)
605 show multiple-symbols
606 The value of this variable can be changed to adjust the debugger behavior
607 when an expression or a breakpoint location contains an ambiguous symbol
608 name (an overloaded function name, for instance).
610 set breakpoint always-inserted
611 show breakpoint always-inserted
612 Keep breakpoints always inserted in the target, as opposed to inserting
613 them when resuming the target, and removing them when the target stops.
614 This option can improve debugger performance on slow remote targets.
616 set arm fallback-mode (arm|thumb|auto)
617 show arm fallback-mode
618 set arm force-mode (arm|thumb|auto)
620 These commands control how ARM GDB determines whether instructions
621 are ARM or Thumb. The default for both settings is auto, which uses
622 the current CPSR value for instructions without symbols; previous
623 versions of GDB behaved as if "set arm fallback-mode arm".
625 set disable-randomization
626 show disable-randomization
627 Standalone programs run with the virtual address space randomization enabled
628 by default on some platforms. This option keeps the addresses stable across
629 multiple debugging sessions.
633 Control whether other threads are stopped or not when some thread hits
638 Requests that asynchronous execution is enabled in the target, if available.
639 In this case, it's possible to resume target in the background, and interact
640 with GDB while the target is running. "show target-async" displays the
641 current state of asynchronous execution of the target.
643 set target-wide-charset
644 show target-wide-charset
645 The target-wide-charset is the name of the character set that GDB
646 uses when printing characters whose type is wchar_t.
648 set tcp auto-retry (on|off)
650 set tcp connect-timeout
651 show tcp connect-timeout
652 These commands allow GDB to retry failed TCP connections to a remote stub
653 with a specified timeout period; this is useful if the stub is launched
654 in parallel with GDB but may not be ready to accept connections immediately.
656 set libthread-db-search-path
657 show libthread-db-search-path
658 Control list of directories which GDB will search for appropriate
661 set schedule-multiple (on|off)
662 show schedule-multiple
663 Allow GDB to resume all threads of all processes or only threads of
668 Use more aggressive caching for accesses to the stack. This improves
669 performance of remote debugging (particularly backtraces) without
670 affecting correctness.
672 set interactive-mode (on|off|auto)
673 show interactive-mode
674 Control whether GDB runs in interactive mode (on) or not (off).
675 When in interactive mode, GDB waits for the user to answer all
676 queries. Otherwise, GDB does not wait and assumes the default
677 answer. When set to auto (the default), GDB determines which
678 mode to use based on the stdin settings.
683 For program forks, this is replaced by the new more generic `info
684 inferiors' command. To list checkpoints, you can still use the
685 `info checkpoints' command, which was an alias for the `info forks'
689 Replaced by the new `inferior' command. To switch between
690 checkpoints, you can still use the `restart' command, which was an
691 alias for the `fork' command.
694 This is removed, since some targets don't have a notion of
695 processes. To switch between processes, you can still use the
696 `inferior' command using GDB's own inferior number.
699 For program forks, this is replaced by the new more generic `kill
700 inferior' command. To delete a checkpoint, you can still use the
701 `delete checkpoint' command, which was an alias for the `delete
705 For program forks, this is replaced by the new more generic `detach
706 inferior' command. To detach a checkpoint, you can still use the
707 `detach checkpoint' command, which was an alias for the `detach
710 * New native configurations
712 x86/x86_64 Darwin i[34567]86-*-darwin*
714 x86_64 MinGW x86_64-*-mingw*
718 Lattice Mico32 lm32-*
719 x86 DICOS i[34567]86-*-dicos*
720 x86_64 DICOS x86_64-*-dicos*
723 * The GDB remote stub, gdbserver, now supports x86 Windows CE
724 (mingw32ce) debugging.
730 These commands were actually not implemented on any target.
732 *** Changes in GDB 6.8
734 * New native configurations
736 NetBSD/hppa hppa*-*netbsd*
737 Xtensa GNU/Linux xtensa*-*-linux*
741 NetBSD/hppa hppa*-*-netbsd*
742 Xtensa GNU/Lunux xtensa*-*-linux*
744 * Change in command line behavior -- corefiles vs. process ids.
746 When the '-p NUMBER' or '--pid NUMBER' options are used, and
747 attaching to process NUMBER fails, GDB no longer attempts to open a
748 core file named NUMBER. Attaching to a program using the -c option
749 is no longer supported. Instead, use the '-p' or '--pid' options.
751 * GDB can now be built as a native debugger for debugging Windows x86
752 (mingw32) Portable Executable (PE) programs.
754 * Pending breakpoints no longer change their number when their address
757 * GDB now supports breakpoints with multiple locations,
758 including breakpoints on C++ constructors, inside C++ templates,
759 and in inlined functions.
761 * GDB's ability to debug optimized code has been improved. GDB more
762 accurately identifies function bodies and lexical blocks that occupy
763 more than one contiguous range of addresses.
765 * Target descriptions can now describe registers for PowerPC.
767 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
768 registers on PowerPC targets.
770 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
771 targets even when the libthread_db library is not available.
773 * The GDB remote stub, gdbserver, now supports the new file transfer
774 commands (remote put, remote get, and remote delete).
776 * The GDB remote stub, gdbserver, now supports run and attach in
777 extended-remote mode.
779 * hppa*64*-*-hpux11* target broken
780 The debugger is unable to start a program and fails with the following
781 error: "Error trying to get information about dynamic linker".
782 The gdb-6.7 release is also affected.
784 * GDB now supports the --enable-targets= configure option to allow
785 building a single GDB executable that supports multiple remote
786 target architectures.
788 * GDB now supports debugging C and C++ programs which use the
789 Decimal Floating Point extension. In addition, the PowerPC target
790 now has a set of pseudo-registers to inspect decimal float values
791 stored in two consecutive float registers.
793 * The -break-insert MI command can optionally create pending
796 * Improved support for debugging Ada
797 Many improvements to the Ada language support have been made. These
799 - Better support for Ada2005 interface types
800 - Improved handling of arrays and slices in general
801 - Better support for Taft-amendment types
802 - The '{type} ADDRESS' expression is now allowed on the left hand-side
804 - Improved command completion in Ada
807 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
812 set print frame-arguments (all|scalars|none)
813 show print frame-arguments
814 The value of this variable can be changed to control which argument
815 values should be printed by the debugger when displaying a frame.
820 Transfer files to and from a remote target, and delete remote files.
827 Transfer files to and from a remote target, and delete remote files.
836 Open, close, read, write, and delete files on the remote system.
839 Attach to an existing process on the remote system, in extended-remote
843 Run a new process on the remote system, in extended-remote mode.
845 *** Changes in GDB 6.7
847 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
848 bfd, libiberty and opcodes, as revealed by static analysis donated by
849 Coverity, Inc. (http://scan.coverity.com).
851 * When looking up multiply-defined global symbols, GDB will now prefer the
852 symbol definition in the current shared library if it was built using the
853 -Bsymbolic linker option.
855 * When the Text User Interface (TUI) is not configured, GDB will now
856 recognize the -tui command-line option and print a message that the TUI
859 * The GDB remote stub, gdbserver, now has lower overhead for high
860 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
862 * GDB for MIPS targets now autodetects whether a remote target provides
863 32-bit or 64-bit register values.
865 * Support for C++ member pointers has been improved.
867 * GDB now understands XML target descriptions, which specify the
868 target's overall architecture. GDB can read a description from
869 a local file or over the remote serial protocol.
871 * Vectors of single-byte data use a new integer type which is not
872 automatically displayed as character or string data.
874 * The /s format now works with the print command. It displays
875 arrays of single-byte integers and pointers to single-byte integers
878 * Target descriptions can now describe target-specific registers,
879 for architectures which have implemented the support (currently
880 only ARM, M68K, and MIPS).
882 * GDB and the GDB remote stub, gdbserver, now support the XScale
885 * The GDB remote stub, gdbserver, has been updated to support
886 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
887 has been rewritten to use the standard GDB remote protocol.
889 * GDB can now step into C++ functions which are called through thunks.
891 * GDB for the Cell/B.E. SPU now supports overlay debugging.
893 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
894 layout. It also supports a TextSeg= and DataSeg= response when only
895 segment base addresses (rather than offsets) are available.
897 * The /i format now outputs any trailing branch delay slot instructions
898 immediately following the last instruction within the count specified.
900 * The GDB remote protocol "T" stop reply packet now supports a
901 "library" response. Combined with the new "qXfer:libraries:read"
902 packet, this response allows GDB to debug shared libraries on targets
903 where the operating system manages the list of loaded libraries (e.g.
904 Windows and SymbianOS).
906 * The GDB remote stub, gdbserver, now supports dynamic link libraries
907 (DLLs) on Windows and Windows CE targets.
909 * GDB now supports a faster verification that a .debug file matches its binary
910 according to its build-id signature, if the signature is present.
916 Enable or disable hardware flow control (RTS/CTS) on the serial port
917 when debugging using remote targets.
919 set mem inaccessible-by-default
920 show mem inaccessible-by-default
921 If the target supplies a memory map, for instance via the remote
922 protocol's "qXfer:memory-map:read" packet, setting this variable
923 prevents GDB from accessing memory outside the memory map. This
924 is useful for targets with memory mapped registers or which react
925 badly to accesses of unmapped address space.
927 set breakpoint auto-hw
928 show breakpoint auto-hw
929 If the target supplies a memory map, for instance via the remote
930 protocol's "qXfer:memory-map:read" packet, setting this variable
931 lets GDB use hardware breakpoints automatically for memory regions
932 where it can not use software breakpoints. This covers both the
933 "break" command and internal breakpoints used for other commands
934 including "next" and "finish".
937 catch exception unhandled
938 Stop the program execution when Ada exceptions are raised.
941 Stop the program execution when an Ada assertion failed.
945 Set an alternate system root for target files. This is a more
946 general version of "set solib-absolute-prefix", which is now
947 an alias to "set sysroot".
950 Provide extended SPU facility status information. This set of
951 commands is available only when debugging the Cell/B.E. SPU
954 * New native configurations
956 OpenBSD/sh sh*-*openbsd*
961 Use the specified local file as an XML target description, and do
962 not query the target for its built-in description.
966 OpenBSD/sh sh*-*-openbsd*
967 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
968 Toshiba Media Processor mep-elf
973 Ignore the specified signals; pass them directly to the debugged program
974 without stopping other threads or reporting them to GDB.
977 Read an XML target description from the target, which describes its
982 Read or write contents of an spufs file on the target system. These
983 packets are available only on the Cell/B.E. SPU architecture.
985 qXfer:libraries:read:
986 Report the loaded shared libraries. Combined with new "T" packet
987 response, this packet allows GDB to debug shared libraries on
988 targets where the operating system manages the list of loaded
989 libraries (e.g. Windows and SymbianOS).
993 Support for these obsolete configurations has been removed.
1001 i[34567]86-*-lynxos*
1002 i[34567]86-*-netware*
1003 i[34567]86-*-sco3.2v5*
1004 i[34567]86-*-sco3.2v4*
1006 i[34567]86-*-sysv4.2*
1009 i[34567]86-*-unixware2*
1010 i[34567]86-*-unixware*
1019 * Other removed features
1026 Various m68k-only ROM monitors.
1033 Various Renesas ROM monitors and debugging interfaces for SH and
1038 Support for a Macraigor serial interface to on-chip debugging.
1039 GDB does not directly support the newer parallel or USB
1044 A debug information format. The predecessor to DWARF 2 and
1045 DWARF 3, which are still supported.
1047 Support for the HP aCC compiler on HP-UX/PA-RISC
1049 SOM-encapsulated symbolic debugging information, automatic
1050 invocation of pxdb, and the aCC custom C++ ABI. This does not
1051 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1052 with aCC can still be debugged on an assembly level.
1054 MIPS ".pdr" sections
1056 A MIPS-specific format used to describe stack frame layout
1057 in debugging information.
1061 GDB could work with an older version of Guile to debug
1062 the interpreter and Scheme programs running in it.
1064 set mips stack-arg-size
1065 set mips saved-gpreg-size
1067 Use "set mips abi" to control parameter passing for MIPS.
1069 *** Changes in GDB 6.6
1074 Cell Broadband Engine SPU spu-elf
1076 * GDB can now be configured as a cross-debugger targeting native Windows
1077 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1078 running on a Windows system over TCP/IP to debug Windows programs.
1080 * The GDB remote stub, gdbserver, has been updated to support Windows and
1081 Cygwin debugging. Both single-threaded and multi-threaded programs are
1084 * The "set trust-readonly-sections" command works again. This command was
1085 broken in GDB 6.3, 6.4, and 6.5.
1087 * The "load" command now supports writing to flash memory, if the remote
1088 stub provides the required support.
1090 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1091 longer requires symbolic debug information (e.g. DWARF-2).
1096 unset substitute-path
1097 show substitute-path
1098 Manage a list of substitution rules that GDB uses to rewrite the name
1099 of the directories where the sources are located. This can be useful
1100 for instance when the sources were moved to a different location
1101 between compilation and debugging.
1105 Print each CLI command as it is executed. Each command is prefixed with
1106 a number of `+' symbols representing the nesting depth.
1107 The source command now has a `-v' option to enable the same feature.
1111 The ARM Demon monitor support (RDP protocol, "target rdp").
1113 Kernel Object Display, an embedded debugging feature which only worked with
1114 an obsolete version of Cisco IOS.
1116 The 'set download-write-size' and 'show download-write-size' commands.
1118 * New remote packets
1121 Tell a stub about GDB client features, and request remote target features.
1122 The first feature implemented is PacketSize, which allows the target to
1123 specify the size of packets it can handle - to minimize the number of
1124 packets required and improve performance when connected to a remote
1128 Fetch an OS auxilliary vector from the remote stub. This packet is a
1129 more efficient replacement for qPart:auxv:read.
1131 qXfer:memory-map:read:
1132 Fetch a memory map from the remote stub, including information about
1133 RAM, ROM, and flash memory devices.
1138 Erase and program a flash memory device.
1140 * Removed remote packets
1143 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1144 used it, and only gdbserver implemented it.
1146 *** Changes in GDB 6.5
1150 Renesas M32C/M16C m32c-elf
1152 Morpho Technologies ms1 ms1-elf
1156 init-if-undefined Initialize a convenience variable, but
1157 only if it doesn't already have a value.
1159 The following commands are presently only implemented for native GNU/Linux:
1161 checkpoint Save a snapshot of the program state.
1163 restart <n> Return the program state to a
1164 previously saved state.
1166 info checkpoints List currently saved checkpoints.
1168 delete-checkpoint <n> Delete a previously saved checkpoint.
1170 set|show detach-on-fork Tell gdb whether to detach from a newly
1171 forked process, or to keep debugging it.
1173 info forks List forks of the user program that
1174 are available to be debugged.
1176 fork <n> Switch to debugging one of several
1177 forks of the user program that are
1178 available to be debugged.
1180 delete-fork <n> Delete a fork from the list of forks
1181 that are available to be debugged (and
1182 kill the forked process).
1184 detach-fork <n> Delete a fork from the list of forks
1185 that are available to be debugged (and
1186 allow the process to continue).
1190 Morpho Technologies ms2 ms1-elf
1192 * Improved Windows host support
1194 GDB now builds as a cross debugger hosted on i686-mingw32, including
1195 native console support, and remote communications using either
1196 network sockets or serial ports.
1198 * Improved Modula-2 language support
1200 GDB can now print most types in the Modula-2 syntax. This includes:
1201 basic types, set types, record types, enumerated types, range types,
1202 pointer types and ARRAY types. Procedure var parameters are correctly
1203 printed and hexadecimal addresses and character constants are also
1204 written in the Modula-2 syntax. Best results can be obtained by using
1205 GNU Modula-2 together with the -gdwarf-2 command line option.
1209 The ARM rdi-share module.
1211 The Netware NLM debug server.
1213 *** Changes in GDB 6.4
1215 * New native configurations
1217 OpenBSD/arm arm*-*-openbsd*
1218 OpenBSD/mips64 mips64-*-openbsd*
1222 Morpho Technologies ms1 ms1-elf
1224 * New command line options
1226 --batch-silent As for --batch, but totally silent.
1227 --return-child-result The debugger will exist with the same value
1228 the child (debugged) program exited with.
1229 --eval-command COMMAND, -ex COMMAND
1230 Execute a single GDB CLI command. This may be
1231 specified multiple times and in conjunction
1232 with the --command (-x) option.
1234 * Deprecated commands removed
1236 The following commands, that were deprecated in 2000, have been
1240 set|show arm disassembly-flavor set|show arm disassembler
1241 othernames set arm disassembler
1242 set|show remotedebug set|show debug remote
1243 set|show archdebug set|show debug arch
1244 set|show eventdebug set|show debug event
1247 * New BSD user-level threads support
1249 It is now possible to debug programs using the user-level threads
1250 library on OpenBSD and FreeBSD. Currently supported (target)
1253 FreeBSD/amd64 x86_64-*-freebsd*
1254 FreeBSD/i386 i386-*-freebsd*
1255 OpenBSD/i386 i386-*-openbsd*
1257 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1258 are not yet supported.
1260 * New support for Matsushita MN10300 w/sim added
1261 (Work in progress). mn10300-elf.
1263 * REMOVED configurations and files
1265 VxWorks and the XDR protocol *-*-vxworks
1266 Motorola MCORE mcore-*-*
1267 National Semiconductor NS32000 ns32k-*-*
1269 * New "set print array-indexes" command
1271 After turning this setting "on", GDB prints the index of each element
1272 when displaying arrays. The default is "off" to preserve the previous
1275 * VAX floating point support
1277 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1279 * User-defined command support
1281 In addition to using $arg0..$arg9 for argument passing, it is now possible
1282 to use $argc to determine now many arguments have been passed. See the
1283 section on user-defined commands in the user manual for more information.
1285 *** Changes in GDB 6.3:
1287 * New command line option
1289 GDB now accepts -l followed by a number to set the timeout for remote
1292 * GDB works with GCC -feliminate-dwarf2-dups
1294 GDB now supports a more compact representation of DWARF-2 debug
1295 information using DW_FORM_ref_addr references. These are produced
1296 by GCC with the option -feliminate-dwarf2-dups and also by some
1297 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1298 to use -feliminate-dwarf2-dups.
1300 * Internationalization
1302 When supported by the host system, GDB will be built with
1303 internationalization (libintl). The task of marking up the sources is
1304 continued, we're looking forward to our first translation.
1308 Initial support for debugging programs compiled with the GNAT
1309 implementation of the Ada programming language has been integrated
1310 into GDB. In this release, support is limited to expression evaluation.
1312 * New native configurations
1314 GNU/Linux/m32r m32r-*-linux-gnu
1318 GDB's remote protocol now includes support for the 'p' packet. This
1319 packet is used to fetch individual registers from a remote inferior.
1321 * END-OF-LIFE registers[] compatibility module
1323 GDB's internal register infrastructure has been completely rewritten.
1324 The new infrastructure making possible the implementation of key new
1325 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1328 GDB 6.3 will be the last release to include the the registers[]
1329 compatibility module that allowed out-of-date configurations to
1330 continue to work. This change directly impacts the following
1340 powerpc bdm protocol
1342 Unless there is activity to revive these configurations, they will be
1343 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1345 * OBSOLETE configurations and files
1347 Configurations that have been declared obsolete in this release have
1348 been commented out. Unless there is activity to revive these
1349 configurations, the next release of GDB will have their sources
1350 permanently REMOVED.
1359 *** Changes in GDB 6.2.1:
1361 * MIPS `break main; run' gave an heuristic-fence-post warning
1363 When attempting to run even a simple program, a warning about
1364 heuristic-fence-post being hit would be reported. This problem has
1367 * MIPS IRIX 'long double' crashed GDB
1369 When examining a long double variable, GDB would get a segmentation
1370 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1371 IRIX long double values).
1375 A bug in the VAX stack code was causing problems with the "next"
1376 command. This problem has been fixed.
1378 *** Changes in GDB 6.2:
1380 * Fix for ``many threads''
1382 On GNU/Linux systems that use the NPTL threads library, a program
1383 rapidly creating and deleting threads would confuse GDB leading to the
1386 ptrace: No such process.
1387 thread_db_get_info: cannot get thread info: generic error
1389 This problem has been fixed.
1391 * "-async" and "-noasync" options removed.
1393 Support for the broken "-noasync" option has been removed (it caused
1396 * New ``start'' command.
1398 This command runs the program until the begining of the main procedure.
1400 * New BSD Kernel Data Access Library (libkvm) interface
1402 Using ``target kvm'' it is now possible to debug kernel core dumps and
1403 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1404 platforms. Currently supported (native-only) configurations are:
1406 FreeBSD/amd64 x86_64-*-freebsd*
1407 FreeBSD/i386 i?86-*-freebsd*
1408 NetBSD/i386 i?86-*-netbsd*
1409 NetBSD/m68k m68*-*-netbsd*
1410 NetBSD/sparc sparc-*-netbsd*
1411 OpenBSD/amd64 x86_64-*-openbsd*
1412 OpenBSD/i386 i?86-*-openbsd*
1413 OpenBSD/m68k m68*-openbsd*
1414 OpenBSD/sparc sparc-*-openbsd*
1416 * Signal trampoline code overhauled
1418 Many generic problems with GDB's signal handling code have been fixed.
1419 These include: backtraces through non-contiguous stacks; recognition
1420 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1421 call; backtrace through a signal trampoline; step into and out of
1422 signal handlers; and single-stepping in the signal trampoline.
1424 Please note that kernel bugs are a limiting factor here. These
1425 features have been shown to work on an s390 GNU/Linux system that
1426 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1428 * Cygwin support for DWARF 2 added.
1430 * New native configurations
1432 GNU/Linux/hppa hppa*-*-linux*
1433 OpenBSD/hppa hppa*-*-openbsd*
1434 OpenBSD/m68k m68*-*-openbsd*
1435 OpenBSD/m88k m88*-*-openbsd*
1436 OpenBSD/powerpc powerpc-*-openbsd*
1437 NetBSD/vax vax-*-netbsd*
1438 OpenBSD/vax vax-*-openbsd*
1440 * END-OF-LIFE frame compatibility module
1442 GDB's internal frame infrastructure has been completely rewritten.
1443 The new infrastructure making it possible to support key new features
1444 including DWARF 2 Call Frame Information. To aid in the task of
1445 migrating old configurations to this new infrastructure, a
1446 compatibility module, that allowed old configurations to continue to
1447 work, was also included.
1449 GDB 6.2 will be the last release to include this frame compatibility
1450 module. This change directly impacts the following configurations:
1460 Unless there is activity to revive these configurations, they will be
1461 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1463 * REMOVED configurations and files
1465 Sun 3, running SunOS 3 m68*-*-sunos3*
1466 Sun 3, running SunOS 4 m68*-*-sunos4*
1467 Sun 2, running SunOS 3 m68000-*-sunos3*
1468 Sun 2, running SunOS 4 m68000-*-sunos4*
1469 Motorola 680x0 running LynxOS m68*-*-lynxos*
1470 AT&T 3b1/Unix pc m68*-att-*
1471 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1472 decstation mips-dec-* mips-little-*
1473 riscos mips-*-riscos* mips-*-sysv*
1474 sonymips mips-sony-*
1475 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1477 *** Changes in GDB 6.1.1:
1479 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1481 The TUI (Text-mode User Interface) is now built as part of a default
1482 GDB configuration. It is enabled by either selecting the TUI with the
1483 command line option "-i=tui" or by running the separate "gdbtui"
1484 program. For more information on the TUI, see the manual "Debugging
1487 * Pending breakpoint support (also included in GDB 6.1)
1489 Support has been added to allow you to specify breakpoints in shared
1490 libraries that have not yet been loaded. If a breakpoint location
1491 cannot be found, and the "breakpoint pending" option is set to auto,
1492 GDB queries you if you wish to make the breakpoint pending on a future
1493 shared-library load. If and when GDB resolves the breakpoint symbol,
1494 the pending breakpoint is removed as one or more regular breakpoints
1497 Pending breakpoints are very useful for GCJ Java debugging.
1499 * Fixed ISO-C build problems
1501 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1502 non ISO-C code that stopped them being built using a more strict ISO-C
1503 compiler (e.g., IBM's C compiler).
1505 * Fixed build problem on IRIX 5
1507 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1508 wasn't able to compile compile on an IRIX 5 system.
1510 * Added execute permission to gdb/gdbserver/configure
1512 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1513 permission. This bug would cause configure to fail on a number of
1514 systems (Solaris, IRIX). Ref: server/519.
1516 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1518 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1519 has been updated to use constant array sizes.
1521 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1523 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1524 its generated DWARF Call Frame Info. This encoding was causing GDB to
1525 panic, that panic has been fixed. Ref: gdb/1628.
1527 * Fixed a problem when examining parameters in shared library code.
1529 When examining parameters in optimized shared library code generated
1530 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1531 not available''. GDB now correctly displays the variable's value.
1533 *** Changes in GDB 6.1:
1535 * Removed --with-mmalloc
1537 Support for the mmalloc memory manager has been removed, as it
1538 conflicted with the internal gdb byte cache.
1540 * Changes in AMD64 configurations
1542 The AMD64 target now includes the %cs and %ss registers. As a result
1543 the AMD64 remote protocol has changed; this affects the floating-point
1544 and SSE registers. If you rely on those registers for your debugging,
1545 you should upgrade gdbserver on the remote side.
1547 * Revised SPARC target
1549 The SPARC target has been completely revised, incorporating the
1550 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1551 support for LynxOS and SunOS 4 has been dropped. Calling functions
1552 from within GDB on operating systems with a non-executable stack
1553 (Solaris, OpenBSD) now works.
1557 GDB has a new C++ demangler which does a better job on the mangled
1558 names generated by current versions of g++. It also runs faster, so
1559 with this and other changes gdb should now start faster on large C++
1562 * DWARF 2 Location Expressions
1564 GDB support for location expressions has been extended to support function
1565 arguments and frame bases. Older versions of GDB could crash when they
1568 * C++ nested types and namespaces
1570 GDB's support for nested types and namespaces in C++ has been
1571 improved, especially if you use the DWARF 2 debugging format. (This
1572 is the default for recent versions of GCC on most platforms.)
1573 Specifically, if you have a class "Inner" defined within a class or
1574 namespace "Outer", then GDB realizes that the class's name is
1575 "Outer::Inner", not simply "Inner". This should greatly reduce the
1576 frequency of complaints about not finding RTTI symbols. In addition,
1577 if you are stopped at inside of a function defined within a namespace,
1578 GDB modifies its name lookup accordingly.
1580 * New native configurations
1582 NetBSD/amd64 x86_64-*-netbsd*
1583 OpenBSD/amd64 x86_64-*-openbsd*
1584 OpenBSD/alpha alpha*-*-openbsd*
1585 OpenBSD/sparc sparc-*-openbsd*
1586 OpenBSD/sparc64 sparc64-*-openbsd*
1588 * New debugging protocols
1590 M32R with SDI protocol m32r-*-elf*
1592 * "set prompt-escape-char" command deleted.
1594 The command "set prompt-escape-char" has been deleted. This command,
1595 and its very obscure effet on GDB's prompt, was never documented,
1596 tested, nor mentioned in the NEWS file.
1598 * OBSOLETE configurations and files
1600 Configurations that have been declared obsolete in this release have
1601 been commented out. Unless there is activity to revive these
1602 configurations, the next release of GDB will have their sources
1603 permanently REMOVED.
1605 Sun 3, running SunOS 3 m68*-*-sunos3*
1606 Sun 3, running SunOS 4 m68*-*-sunos4*
1607 Sun 2, running SunOS 3 m68000-*-sunos3*
1608 Sun 2, running SunOS 4 m68000-*-sunos4*
1609 Motorola 680x0 running LynxOS m68*-*-lynxos*
1610 AT&T 3b1/Unix pc m68*-att-*
1611 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1612 decstation mips-dec-* mips-little-*
1613 riscos mips-*-riscos* mips-*-sysv*
1614 sonymips mips-sony-*
1615 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1617 * REMOVED configurations and files
1619 SGI Irix-4.x mips-sgi-irix4 or iris4
1620 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1621 Z8000 simulator z8k-zilog-none or z8ksim
1622 Matsushita MN10200 w/simulator mn10200-*-*
1623 H8/500 simulator h8500-hitachi-hms or h8500hms
1624 HP/PA running BSD hppa*-*-bsd*
1625 HP/PA running OSF/1 hppa*-*-osf*
1626 HP/PA Pro target hppa*-*-pro*
1627 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1628 386BSD i[3456]86-*-bsd*
1629 Sequent family i[3456]86-sequent-sysv4*
1630 i[3456]86-sequent-sysv*
1631 i[3456]86-sequent-bsd*
1632 SPARC running LynxOS sparc-*-lynxos*
1633 SPARC running SunOS 4 sparc-*-sunos4*
1634 Tsqware Sparclet sparclet-*-*
1635 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1637 *** Changes in GDB 6.0:
1641 Support for debugging the Objective-C programming language has been
1642 integrated into GDB.
1644 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1646 DWARF 2's Call Frame Information makes available compiler generated
1647 information that more exactly describes the program's run-time stack.
1648 By using this information, GDB is able to provide more robust stack
1651 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1652 have been updated to use a new backtrace mechanism which includes
1653 DWARF 2 CFI support.
1657 GDB's remote protocol has been extended to include support for hosted
1658 file I/O (where the remote target uses GDB's file system). See GDB's
1659 remote protocol documentation for details.
1661 * All targets using the new architecture framework.
1663 All of GDB's targets have been updated to use the new internal
1664 architecture framework. The way is now open for future GDB releases
1665 to include cross-architecture native debugging support (i386 on amd64,
1668 * GNU/Linux's Thread Local Storage (TLS)
1670 GDB now includes support for for the GNU/Linux implementation of
1671 per-thread variables.
1673 * GNU/Linux's Native POSIX Thread Library (NPTL)
1675 GDB's thread code has been updated to work with either the new
1676 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1678 * Separate debug info.
1680 GDB, in conjunction with BINUTILS, now supports a mechanism for
1681 automatically loading debug information from a separate file. Instead
1682 of shipping full debug and non-debug versions of system libraries,
1683 system integrators can now instead ship just the stripped libraries
1684 and optional debug files.
1686 * DWARF 2 Location Expressions
1688 DWARF 2 Location Expressions allow the compiler to more completely
1689 describe the location of variables (even in optimized code) to the
1692 GDB now includes preliminary support for location expressions (support
1693 for DW_OP_piece is still missing).
1697 A number of long standing bugs that caused GDB to die while starting a
1698 Java application have been fixed. GDB's Java support is now
1699 considered "useable".
1701 * GNU/Linux support for fork, vfork, and exec.
1703 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1704 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1707 * GDB supports logging output to a file
1709 There are two new commands, "set logging" and "show logging", which can be
1710 used to capture GDB's output to a file.
1712 * The meaning of "detach" has changed for gdbserver
1714 The "detach" command will now resume the application, as documented. To
1715 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1718 * d10v, m68hc11 `regs' command deprecated
1720 The `info registers' command has been updated so that it displays the
1721 registers using a format identical to the old `regs' command.
1725 A new command, "maint set profile on/off", has been added. This command can
1726 be used to enable or disable profiling while running GDB, to profile a
1727 session or a set of commands. In addition there is a new configure switch,
1728 "--enable-profiling", which will cause GDB to be compiled with profiling
1729 data, for more informative profiling results.
1731 * Default MI syntax changed to "mi2".
1733 The default MI (machine interface) syntax, enabled by the command line
1734 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1735 "mi1", can be enabled by specifying the option "-i=mi1".
1737 Support for the original "mi0" syntax (included in GDB 5.0) has been
1740 Fix for gdb/192: removed extraneous space when displaying frame level.
1741 Fix for gdb/672: update changelist is now output in mi list format.
1742 Fix for gdb/702: a -var-assign that updates the value now shows up
1743 in a subsequent -var-update.
1745 * New native configurations.
1747 FreeBSD/amd64 x86_64-*-freebsd*
1749 * Multi-arched targets.
1751 HP/PA HPUX11 hppa*-*-hpux*
1752 Renesas M32R/D w/simulator m32r-*-elf*
1754 * OBSOLETE configurations and files
1756 Configurations that have been declared obsolete in this release have
1757 been commented out. Unless there is activity to revive these
1758 configurations, the next release of GDB will have their sources
1759 permanently REMOVED.
1761 Z8000 simulator z8k-zilog-none or z8ksim
1762 Matsushita MN10200 w/simulator mn10200-*-*
1763 H8/500 simulator h8500-hitachi-hms or h8500hms
1764 HP/PA running BSD hppa*-*-bsd*
1765 HP/PA running OSF/1 hppa*-*-osf*
1766 HP/PA Pro target hppa*-*-pro*
1767 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1768 Sequent family i[3456]86-sequent-sysv4*
1769 i[3456]86-sequent-sysv*
1770 i[3456]86-sequent-bsd*
1771 Tsqware Sparclet sparclet-*-*
1772 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1774 * REMOVED configurations and files
1777 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1778 IBM AIX PS/2 i[3456]86-*-aix
1779 i386 running Mach 3.0 i[3456]86-*-mach3*
1780 i386 running Mach i[3456]86-*-mach*
1781 i386 running OSF/1 i[3456]86-*osf1mk*
1782 HP/Apollo 68k Family m68*-apollo*-sysv*,
1784 m68*-hp-bsd*, m68*-hp-hpux*
1785 Argonaut Risc Chip (ARC) arc-*-*
1786 Mitsubishi D30V d30v-*-*
1787 Fujitsu FR30 fr30-*-elf*
1788 OS/9000 i[34]86-*-os9k
1789 I960 with MON960 i960-*-coff
1791 * MIPS $fp behavior changed
1793 The convenience variable $fp, for the MIPS, now consistently returns
1794 the address of the current frame's base. Previously, depending on the
1795 context, $fp could refer to either $sp or the current frame's base
1796 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1797 The GNU Source-Level Debugger''.
1799 *** Changes in GDB 5.3:
1801 * GNU/Linux shared library multi-threaded performance improved.
1803 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1804 `/proc', in preference to `ptrace' for memory reads. This may result
1805 in an improvement in the start-up time of multi-threaded, shared
1806 library applications when run under GDB. One GDB user writes: ``loads
1807 shared libs like mad''.
1809 * ``gdbserver'' now supports multi-threaded applications on some targets
1811 Support for debugging multi-threaded applications which use
1812 the GNU/Linux LinuxThreads package has been added for
1813 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1814 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1816 * GDB now supports C/C++ preprocessor macros.
1818 GDB now expands preprocessor macro invocations in C/C++ expressions,
1819 and provides various commands for showing macro definitions and how
1822 The new command `macro expand EXPRESSION' expands any macro
1823 invocations in expression, and shows the result.
1825 The new command `show macro MACRO-NAME' shows the definition of the
1826 macro named MACRO-NAME, and where it was defined.
1828 Most compilers don't include information about macros in the debugging
1829 information by default. In GCC 3.1, for example, you need to compile
1830 your program with the options `-gdwarf-2 -g3'. If the macro
1831 information is present in the executable, GDB will read it.
1833 * Multi-arched targets.
1835 DEC Alpha (partial) alpha*-*-*
1836 DEC VAX (partial) vax-*-*
1838 National Semiconductor NS32000 (partial) ns32k-*-*
1839 Motorola 68000 (partial) m68k-*-*
1840 Motorola MCORE mcore-*-*
1844 Fujitsu FRV architecture added by Red Hat frv*-*-*
1847 * New native configurations
1849 Alpha NetBSD alpha*-*-netbsd*
1850 SH NetBSD sh*-*-netbsdelf*
1851 MIPS NetBSD mips*-*-netbsd*
1852 UltraSPARC NetBSD sparc64-*-netbsd*
1854 * OBSOLETE configurations and files
1856 Configurations that have been declared obsolete in this release have
1857 been commented out. Unless there is activity to revive these
1858 configurations, the next release of GDB will have their sources
1859 permanently REMOVED.
1861 Mitsubishi D30V d30v-*-*
1862 OS/9000 i[34]86-*-os9k
1863 IBM AIX PS/2 i[3456]86-*-aix
1864 Fujitsu FR30 fr30-*-elf*
1865 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1866 Argonaut Risc Chip (ARC) arc-*-*
1867 i386 running Mach 3.0 i[3456]86-*-mach3*
1868 i386 running Mach i[3456]86-*-mach*
1869 i386 running OSF/1 i[3456]86-*osf1mk*
1870 HP/Apollo 68k Family m68*-apollo*-sysv*,
1872 m68*-hp-bsd*, m68*-hp-hpux*
1873 I960 with MON960 i960-*-coff
1875 * OBSOLETE languages
1877 CHILL, a Pascal like language used by telecommunications companies.
1879 * REMOVED configurations and files
1881 AMD 29k family via UDI a29k-amd-udi, udi29k
1882 A29K VxWorks a29k-*-vxworks
1883 AMD 29000 embedded, using EBMON a29k-none-none
1884 AMD 29000 embedded with COFF a29k-none-coff
1885 AMD 29000 embedded with a.out a29k-none-aout
1887 testsuite/gdb.hp/gdb.threads-hp/ directory
1889 * New command "set max-user-call-depth <nnn>"
1891 This command allows the user to limit the call depth of user-defined
1892 commands. The default is 1024.
1894 * Changes in FreeBSD/i386 native debugging.
1896 Support for the "generate-core-file" has been added.
1898 * New commands "dump", "append", and "restore".
1900 These commands allow data to be copied from target memory
1901 to a bfd-format or binary file (dump and append), and back
1902 from a file into memory (restore).
1904 * Improved "next/step" support on multi-processor Alpha Tru64.
1906 The previous single-step mechanism could cause unpredictable problems,
1907 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1908 of a software single-step mechanism prevents this.
1910 *** Changes in GDB 5.2.1:
1918 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1919 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1920 Fix, by Joel Brobecker imported from mainline.
1922 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1923 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1924 Fix, by Fred Fish, imported from mainline.
1926 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1927 Surprisingly enough, it works now.
1928 By Michal Ludvig, imported from mainline.
1930 i386 hardware watchpoint support:
1931 avoid misses on second run for some targets.
1932 By Pierre Muller, imported from mainline.
1934 *** Changes in GDB 5.2:
1936 * New command "set trust-readonly-sections on[off]".
1938 This command is a hint that tells gdb that read-only sections
1939 really are read-only (ie. that their contents will not change).
1940 In this mode, gdb will go to the object file rather than the
1941 target to read memory from read-only sections (such as ".text").
1942 This can be a significant performance improvement on some
1943 (notably embedded) targets.
1945 * New command "generate-core-file" (or "gcore").
1947 This new gdb command allows the user to drop a core file of the child
1948 process state at any time. So far it's been implemented only for
1949 GNU/Linux and Solaris, but should be relatively easily ported to other
1950 hosts. Argument is core file name (defaults to core.<pid>).
1952 * New command line option
1954 GDB now accepts --pid or -p followed by a process id.
1956 * Change in command line behavior -- corefiles vs. process ids.
1958 There is a subtle behavior in the way in which GDB handles
1959 command line arguments. The first non-flag argument is always
1960 a program to debug, but the second non-flag argument may either
1961 be a corefile or a process id. Previously, GDB would attempt to
1962 open the second argument as a corefile, and if that failed, would
1963 issue a superfluous error message and then attempt to attach it as
1964 a process. Now, if the second argument begins with a non-digit,
1965 it will be treated as a corefile. If it begins with a digit,
1966 GDB will attempt to attach it as a process, and if no such process
1967 is found, will then attempt to open it as a corefile.
1969 * Changes in ARM configurations.
1971 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1972 configuration is fully multi-arch.
1974 * New native configurations
1976 ARM NetBSD arm*-*-netbsd*
1977 x86 OpenBSD i[3456]86-*-openbsd*
1978 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1979 Sparc64 running FreeBSD sparc64-*-freebsd*
1983 Sanyo XStormy16 xstormy16-elf
1985 * OBSOLETE configurations and files
1987 Configurations that have been declared obsolete in this release have
1988 been commented out. Unless there is activity to revive these
1989 configurations, the next release of GDB will have their sources
1990 permanently REMOVED.
1992 AMD 29k family via UDI a29k-amd-udi, udi29k
1993 A29K VxWorks a29k-*-vxworks
1994 AMD 29000 embedded, using EBMON a29k-none-none
1995 AMD 29000 embedded with COFF a29k-none-coff
1996 AMD 29000 embedded with a.out a29k-none-aout
1998 testsuite/gdb.hp/gdb.threads-hp/ directory
2000 * REMOVED configurations and files
2002 TI TMS320C80 tic80-*-*
2004 PowerPC Solaris powerpcle-*-solaris*
2005 PowerPC Windows NT powerpcle-*-cygwin32
2006 PowerPC Netware powerpc-*-netware*
2007 Harris/CXUX m88k m88*-harris-cxux*
2008 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2009 ns32k-utek-sysv* ns32k-utek-*
2010 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2011 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2012 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2013 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2014 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2016 * Changes to command line processing
2018 The new `--args' feature can be used to specify command-line arguments
2019 for the inferior from gdb's command line.
2021 * Changes to key bindings
2023 There is a new `operate-and-get-next' function bound to `C-o'.
2025 *** Changes in GDB 5.1.1
2027 Fix compile problem on DJGPP.
2029 Fix a problem with floating-point registers on the i386 being
2032 Fix to stop GDB crashing on .debug_str debug info.
2034 Numerous documentation fixes.
2036 Numerous testsuite fixes.
2038 *** Changes in GDB 5.1:
2040 * New native configurations
2042 Alpha FreeBSD alpha*-*-freebsd*
2043 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2044 MIPS GNU/Linux mips*-*-linux*
2045 MIPS SGI Irix 6.x mips*-sgi-irix6*
2046 ia64 AIX ia64-*-aix*
2047 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2051 Motorola 68HC11 and 68HC12 m68hc11-elf
2053 UltraSparc running GNU/Linux sparc64-*-linux*
2055 * OBSOLETE configurations and files
2057 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2058 Harris/CXUX m88k m88*-harris-cxux*
2059 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2060 ns32k-utek-sysv* ns32k-utek-*
2061 TI TMS320C80 tic80-*-*
2063 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2064 PowerPC Solaris powerpcle-*-solaris*
2065 PowerPC Windows NT powerpcle-*-cygwin32
2066 PowerPC Netware powerpc-*-netware*
2067 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2068 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2069 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2070 Apple Macintosh (MPW) host N/A
2072 stuff.c (Program to stuff files into a specially prepared space in kdb)
2073 kdb-start.c (Main loop for the standalone kernel debugger)
2075 Configurations that have been declared obsolete in this release have
2076 been commented out. Unless there is activity to revive these
2077 configurations, the next release of GDB will have their sources
2078 permanently REMOVED.
2080 * REMOVED configurations and files
2082 Altos 3068 m68*-altos-*
2083 Convex c1-*-*, c2-*-*
2085 ARM RISCix arm-*-* (as host)
2089 * GDB has been converted to ISO C.
2091 GDB's source code has been converted to ISO C. In particular, the
2092 sources are fully protoized, and rely on standard headers being
2097 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2099 * The MI enabled by default.
2101 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2102 revised and enabled by default. Packages which use GDB as a debugging
2103 engine behind a UI or another front end are encouraged to switch to
2104 using the GDB/MI interface, instead of the old annotations interface
2105 which is now deprecated.
2107 * Support for debugging Pascal programs.
2109 GDB now includes support for debugging Pascal programs. The following
2110 main features are supported:
2112 - Pascal-specific data types such as sets;
2114 - automatic recognition of Pascal sources based on file-name
2117 - Pascal-style display of data types, variables, and functions;
2119 - a Pascal expression parser.
2121 However, some important features are not yet supported.
2123 - Pascal string operations are not supported at all;
2125 - there are some problems with boolean types;
2127 - Pascal type hexadecimal constants are not supported
2128 because they conflict with the internal variables format;
2130 - support for Pascal objects and classes is not full yet;
2132 - unlike Pascal, GDB is case-sensitive for symbol names.
2134 * Changes in completion.
2136 Commands such as `shell', `run' and `set args', which pass arguments
2137 to inferior programs, now complete on file names, similar to what
2138 users expect at the shell prompt.
2140 Commands which accept locations, such as `disassemble', `print',
2141 `breakpoint', `until', etc. now complete on filenames as well as
2142 program symbols. Thus, if you type "break foob TAB", and the source
2143 files linked into the programs include `foobar.c', that file name will
2144 be one of the candidates for completion. However, file names are not
2145 considered for completion after you typed a colon that delimits a file
2146 name from a name of a function in that file, as in "break foo.c:bar".
2148 `set demangle-style' completes on available demangling styles.
2150 * New platform-independent commands:
2152 It is now possible to define a post-hook for a command as well as a
2153 hook that runs before the command. For more details, see the
2154 documentation of `hookpost' in the GDB manual.
2156 * Changes in GNU/Linux native debugging.
2158 Support for debugging multi-threaded programs has been completely
2159 revised for all platforms except m68k and sparc. You can now debug as
2160 many threads as your system allows you to have.
2162 Attach/detach is supported for multi-threaded programs.
2164 Support for SSE registers was added for x86. This doesn't work for
2165 multi-threaded programs though.
2167 * Changes in MIPS configurations.
2169 Multi-arch support is enabled for all MIPS configurations.
2171 GDB can now be built as native debugger on SGI Irix 6.x systems for
2172 debugging n32 executables. (Debugging 64-bit executables is not yet
2175 * Unified support for hardware watchpoints in all x86 configurations.
2177 Most (if not all) native x86 configurations support hardware-assisted
2178 breakpoints and watchpoints in a unified manner. This support
2179 implements debug register sharing between watchpoints, which allows to
2180 put a virtually infinite number of watchpoints on the same address,
2181 and also supports watching regions up to 16 bytes with several debug
2184 The new maintenance command `maintenance show-debug-regs' toggles
2185 debugging print-outs in functions that insert, remove, and test
2186 watchpoints and hardware breakpoints.
2188 * Changes in the DJGPP native configuration.
2190 New command ``info dos sysinfo'' displays assorted information about
2191 the CPU, OS, memory, and DPMI server.
2193 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2194 display information about segment descriptors stored in GDT, LDT, and
2197 New commands ``info dos pde'' and ``info dos pte'' display entries
2198 from Page Directory and Page Tables (for now works with CWSDPMI only).
2199 New command ``info dos address-pte'' displays the Page Table entry for
2200 a given linear address.
2202 GDB can now pass command lines longer than 126 characters to the
2203 program being debugged (requires an update to the libdbg.a library
2204 which is part of the DJGPP development kit).
2206 DWARF2 debug info is now supported.
2208 It is now possible to `step' and `next' through calls to `longjmp'.
2210 * Changes in documentation.
2212 All GDB documentation was converted to GFDL, the GNU Free
2213 Documentation License.
2215 Tracepoints-related commands are now fully documented in the GDB
2218 TUI, the Text-mode User Interface, is now documented in the manual.
2220 Tracepoints-related commands are now fully documented in the GDB
2223 The "GDB Internals" manual now has an index. It also includes
2224 documentation of `ui_out' functions, GDB coding standards, x86
2225 hardware watchpoints, and memory region attributes.
2227 * GDB's version number moved to ``version.in''
2229 The Makefile variable VERSION has been replaced by the file
2230 ``version.in''. People creating GDB distributions should update the
2231 contents of this file.
2235 GUD support is now a standard part of the EMACS distribution.
2237 *** Changes in GDB 5.0:
2239 * Improved support for debugging FP programs on x86 targets
2241 Unified and much-improved support for debugging floating-point
2242 programs on all x86 targets. In particular, ``info float'' now
2243 displays the FP registers in the same format on all x86 targets, with
2244 greater level of detail.
2246 * Improvements and bugfixes in hardware-assisted watchpoints
2248 It is now possible to watch array elements, struct members, and
2249 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2250 on x86 targets no longer erroneously trigger when the address is
2253 * Improvements in the native DJGPP version of GDB
2255 The distribution now includes all the scripts and auxiliary files
2256 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2257 machines ``out of the box''.
2259 The DJGPP version can now debug programs that use signals. It is
2260 possible to catch signals that happened in the debuggee, deliver
2261 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2262 would kill the program being debugged.) Programs that hook hardware
2263 interrupts (keyboard, timer, etc.) can also be debugged.
2265 It is now possible to debug DJGPP programs that redirect their
2266 standard handles or switch them to raw (as opposed to cooked) mode, or
2267 even close them. The command ``run < foo > bar'' works as expected,
2268 and ``info terminal'' reports useful information about the debuggee's
2269 terminal, including raw/cooked mode, redirection, etc.
2271 The DJGPP version now uses termios functions for console I/O, which
2272 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2275 DOS-style file names with drive letters are now fully supported by
2278 It is now possible to debug DJGPP programs that switch their working
2279 directory. It is also possible to rerun the debuggee any number of
2280 times without restarting GDB; thus, you can use the same setup,
2281 breakpoints, etc. for many debugging sessions.
2283 * New native configurations
2285 ARM GNU/Linux arm*-*-linux*
2286 PowerPC GNU/Linux powerpc-*-linux*
2290 Motorola MCore mcore-*-*
2291 x86 VxWorks i[3456]86-*-vxworks*
2292 PowerPC VxWorks powerpc-*-vxworks*
2293 TI TMS320C80 tic80-*-*
2295 * OBSOLETE configurations
2297 Altos 3068 m68*-altos-*
2298 Convex c1-*-*, c2-*-*
2300 ARM RISCix arm-*-* (as host)
2303 Configurations that have been declared obsolete will be commented out,
2304 but the code will be left in place. If there is no activity to revive
2305 these configurations before the next release of GDB, the sources will
2306 be permanently REMOVED.
2308 * Gould support removed
2310 Support for the Gould PowerNode and NP1 has been removed.
2312 * New features for SVR4
2314 On SVR4 native platforms (such as Solaris), if you attach to a process
2315 without first loading a symbol file, GDB will now attempt to locate and
2316 load symbols from the running process's executable file.
2318 * Many C++ enhancements
2320 C++ support has been greatly improved. Overload resolution now works properly
2321 in almost all cases. RTTI support is on the way.
2323 * Remote targets can connect to a sub-program
2325 A popen(3) style serial-device has been added. This device starts a
2326 sub-process (such as a stand-alone simulator) and then communicates
2327 with that. The sub-program to run is specified using the syntax
2328 ``|<program> <args>'' vis:
2330 (gdb) set remotedebug 1
2331 (gdb) target extended-remote |mn10300-elf-sim program-args
2333 * MIPS 64 remote protocol
2335 A long standing bug in the mips64 remote protocol where by GDB
2336 expected certain 32 bit registers (ex SR) to be transfered as 32
2337 instead of 64 bits has been fixed.
2339 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2340 added to provide backward compatibility with older versions of GDB.
2342 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2344 The command ``set remotebinarydownload'' command has been replaced by
2345 ``set remote X-packet''. Other commands in ``set remote'' family
2346 include ``set remote P-packet''.
2348 * Breakpoint commands accept ranges.
2350 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2351 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2352 ``tracepoint passcount'' also accepts a range of tracepoints.
2354 * ``apropos'' command added.
2356 The ``apropos'' command searches through command names and
2357 documentation strings, printing out matches, making it much easier to
2358 try to find a command that does what you are looking for.
2362 A new machine oriented interface (MI) has been added to GDB. This
2363 interface is designed for debug environments running GDB as a separate
2364 process. This is part of the long term libGDB project. See the
2365 "GDB/MI" chapter of the GDB manual for further information. It can be
2366 enabled by configuring with:
2368 .../configure --enable-gdbmi
2370 *** Changes in GDB-4.18:
2372 * New native configurations
2374 HP-UX 10.20 hppa*-*-hpux10.20
2375 HP-UX 11.x hppa*-*-hpux11.0*
2376 M68K GNU/Linux m68*-*-linux*
2380 Fujitsu FR30 fr30-*-elf*
2381 Intel StrongARM strongarm-*-*
2382 Mitsubishi D30V d30v-*-*
2384 * OBSOLETE configurations
2386 Gould PowerNode, NP1 np1-*-*, pn-*-*
2388 Configurations that have been declared obsolete will be commented out,
2389 but the code will be left in place. If there is no activity to revive
2390 these configurations before the next release of GDB, the sources will
2391 be permanently REMOVED.
2395 As a compatibility experiment, GDB's source files buildsym.h and
2396 buildsym.c have been converted to pure standard C, no longer
2397 containing any K&R compatibility code. We believe that all systems in
2398 use today either come with a standard C compiler, or have a GCC port
2399 available. If this is not true, please report the affected
2400 configuration to bug-gdb@gnu.org immediately. See the README file for
2401 information about getting a standard C compiler if you don't have one
2406 GDB now uses readline 2.2.
2408 * set extension-language
2410 You can now control the mapping between filename extensions and source
2411 languages by using the `set extension-language' command. For instance,
2412 you can ask GDB to treat .c files as C++ by saying
2413 set extension-language .c c++
2414 The command `info extensions' lists all of the recognized extensions
2415 and their associated languages.
2417 * Setting processor type for PowerPC and RS/6000
2419 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2420 you can use the `set processor' command to specify what variant of the
2421 PowerPC family you are debugging. The command
2425 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2426 following PowerPC and RS6000 variants:
2428 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2429 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2431 403GC IBM PowerPC 403GC
2432 505 Motorola PowerPC 505
2433 860 Motorola PowerPC 860 or 850
2434 601 Motorola PowerPC 601
2435 602 Motorola PowerPC 602
2436 603 Motorola/IBM PowerPC 603 or 603e
2437 604 Motorola PowerPC 604 or 604e
2438 750 Motorola/IBM PowerPC 750 or 750
2440 At the moment, this command just tells GDB what to name the
2441 special-purpose processor registers. Since almost all the affected
2442 registers are inaccessible to user-level programs, this command is
2443 only useful for remote debugging in its present form.
2447 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2448 more extensive support for HP-UX. Added features include shared
2449 library support, kernel threads and hardware watchpoints for 11.00,
2450 support for HP's ANSI C and C++ compilers, and a compatibility mode
2451 for xdb and dbx commands.
2455 HP's donation includes the new concept of catchpoints, which is a
2456 generalization of the old catch command. On HP-UX, it is now possible
2457 to catch exec, fork, and vfork, as well as library loading.
2459 This means that the existing catch command has changed; its first
2460 argument now specifies the type of catch to be set up. See the
2461 output of "help catch" for a list of catchpoint types.
2463 * Debugging across forks
2465 On HP-UX, you can choose which process to debug when a fork() happens
2470 HP has donated a curses-based terminal user interface (TUI). To get
2471 it, build with --enable-tui. Although this can be enabled for any
2472 configuration, at present it only works for native HP debugging.
2474 * GDB remote protocol additions
2476 A new protocol packet 'X' that writes binary data is now available.
2477 Default behavior is to try 'X', then drop back to 'M' if the stub
2478 fails to respond. The settable variable `remotebinarydownload'
2479 allows explicit control over the use of 'X'.
2481 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2482 full 64-bit address. The command
2484 set remoteaddresssize 32
2486 can be used to revert to the old behaviour. For existing remote stubs
2487 the change should not be noticed, as the additional address information
2490 In order to assist in debugging stubs, you may use the maintenance
2491 command `packet' to send any text string to the stub. For instance,
2493 maint packet heythere
2495 sends the packet "$heythere#<checksum>". Note that it is very easy to
2496 disrupt a debugging session by sending the wrong packet at the wrong
2499 The compare-sections command allows you to compare section data on the
2500 target to what is in the executable file without uploading or
2501 downloading, by comparing CRC checksums.
2503 * Tracing can collect general expressions
2505 You may now collect general expressions at tracepoints. This requires
2506 further additions to the target-side stub; see tracepoint.c and
2507 doc/agentexpr.texi for further details.
2509 * mask-address variable for Mips
2511 For Mips targets, you may control the zeroing of the upper 32 bits of
2512 a 64-bit address by entering `set mask-address on'. This is mainly
2513 of interest to users of embedded R4xxx and R5xxx processors.
2515 * Higher serial baud rates
2517 GDB's serial code now allows you to specify baud rates 57600, 115200,
2518 230400, and 460800 baud. (Note that your host system may not be able
2519 to achieve all of these rates.)
2523 The i960 configuration now includes an initial implementation of a
2524 builtin simulator, contributed by Jim Wilson.
2527 *** Changes in GDB-4.17:
2529 * New native configurations
2531 Alpha GNU/Linux alpha*-*-linux*
2532 Unixware 2.x i[3456]86-unixware2*
2533 Irix 6.x mips*-sgi-irix6*
2534 PowerPC GNU/Linux powerpc-*-linux*
2535 PowerPC Solaris powerpcle-*-solaris*
2536 Sparc GNU/Linux sparc-*-linux*
2537 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2541 Argonaut Risc Chip (ARC) arc-*-*
2542 Hitachi H8/300S h8300*-*-*
2543 Matsushita MN10200 w/simulator mn10200-*-*
2544 Matsushita MN10300 w/simulator mn10300-*-*
2545 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2546 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2547 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2548 Mitsubishi D10V w/simulator d10v-*-*
2549 Mitsubishi M32R/D w/simulator m32r-*-elf*
2550 Tsqware Sparclet sparclet-*-*
2551 NEC V850 w/simulator v850-*-*
2553 * New debugging protocols
2555 ARM with RDI protocol arm*-*-*
2556 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2557 DDB and LSI variants of PMON protocol mips*-*-*
2558 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2559 PowerPC with SDS protocol powerpc{,le}-*-eabi
2560 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2564 All configurations can now understand and use the DWARF 2 debugging
2565 format. The choice is automatic, if the symbol file contains DWARF 2
2570 GDB now includes basic Java language support. This support is
2571 only useful with Java compilers that produce native machine code.
2573 * solib-absolute-prefix and solib-search-path
2575 For SunOS and SVR4 shared libraries, you may now set the prefix for
2576 loading absolute shared library symbol files, and the search path for
2577 locating non-absolute shared library symbol files.
2579 * Live range splitting
2581 GDB can now effectively debug code for which GCC has performed live
2582 range splitting as part of its optimization. See gdb/doc/LRS for
2583 more details on the expected format of the stabs information.
2587 GDB's support for the GNU Hurd, including thread debugging, has been
2588 updated to work with current versions of the Hurd.
2592 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2593 instruction set. ARM GDB automatically detects when Thumb
2594 instructions are in use, and adjusts disassembly and backtracing
2599 GDB's MIPS target configurations now handle the MIP16 16-bit
2604 GDB now includes support for overlays; if an executable has been
2605 linked such that multiple sections are based at the same address, GDB
2606 will decide which section to use for symbolic info. You can choose to
2607 control the decision manually, using overlay commands, or implement
2608 additional target-side support and use "overlay load-target" to bring
2609 in the overlay mapping. Do "help overlay" for more detail.
2613 The command "info symbol <address>" displays information about
2614 the symbol at the specified address.
2618 The standard remote protocol now includes an extension that allows
2619 asynchronous collection and display of trace data. This requires
2620 extensive support in the target-side debugging stub. Tracing mode
2621 includes a new interaction mode in GDB and new commands: see the
2622 file tracepoint.c for more details.
2626 Configurations for embedded MIPS now include a simulator contributed
2627 by Cygnus Solutions. The simulator supports the instruction sets
2628 of most MIPS variants.
2632 Sparc configurations may now include the ERC32 simulator contributed
2633 by the European Space Agency. The simulator is not built into
2634 Sparc targets by default; configure with --enable-sim to include it.
2638 For target configurations that may include multiple variants of a
2639 basic architecture (such as MIPS and SH), you may now set the
2640 architecture explicitly. "set arch" sets, "info arch" lists
2641 the possible architectures.
2643 *** Changes in GDB-4.16:
2645 * New native configurations
2647 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2648 M68K NetBSD m68k-*-netbsd*
2649 PowerPC AIX 4.x powerpc-*-aix*
2650 PowerPC MacOS powerpc-*-macos*
2651 PowerPC Windows NT powerpcle-*-cygwin32
2652 RS/6000 AIX 4.x rs6000-*-aix4*
2656 ARM with RDP protocol arm-*-*
2657 I960 with MON960 i960-*-coff
2658 MIPS VxWorks mips*-*-vxworks*
2659 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2660 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2662 Matra Sparclet sparclet-*-*
2666 The powerpc-eabi configuration now includes the PSIM simulator,
2667 contributed by Andrew Cagney, with assistance from Mike Meissner.
2668 PSIM is a very elaborate model of the PowerPC, including not only
2669 basic instruction set execution, but also details of execution unit
2670 performance and I/O hardware. See sim/ppc/README for more details.
2674 GDB now works with Solaris 2.5.
2676 * Windows 95/NT native
2678 GDB will now work as a native debugger on Windows 95 and Windows NT.
2679 To build it from source, you must use the "gnu-win32" environment,
2680 which uses a DLL to emulate enough of Unix to run the GNU tools.
2681 Further information, binaries, and sources are available at
2682 ftp.cygnus.com, under pub/gnu-win32.
2684 * dont-repeat command
2686 If a user-defined command includes the command `dont-repeat', then the
2687 command will not be repeated if the user just types return. This is
2688 useful if the command is time-consuming to run, so that accidental
2689 extra keystrokes don't run the same command many times.
2691 * Send break instead of ^C
2693 The standard remote protocol now includes an option to send a break
2694 rather than a ^C to the target in order to interrupt it. By default,
2695 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2697 * Remote protocol timeout
2699 The standard remote protocol includes a new variable `remotetimeout'
2700 that allows you to set the number of seconds before GDB gives up trying
2701 to read from the target. The default value is 2.
2703 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2705 By default GDB will automatically keep track of objects as they are
2706 loaded and unloaded by the dynamic linker. By using the command `set
2707 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2708 when shared library events occur, thus allowing you to set breakpoints
2709 in shared libraries which are explicitly loaded by the inferior.
2711 Note this feature does not work on hpux8. On hpux9 you must link
2712 /usr/lib/end.o into your program. This feature should work
2713 automatically on hpux10.
2715 * Irix 5.x hardware watchpoint support
2717 Irix 5 configurations now support the use of hardware watchpoints.
2719 * Mips protocol "SYN garbage limit"
2721 When debugging a Mips target using the `target mips' protocol, you
2722 may set the number of characters that GDB will ignore by setting
2723 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2724 every character. The default value is 1050.
2726 * Recording and replaying remote debug sessions
2728 If you set `remotelogfile' to the name of a file, gdb will write to it
2729 a recording of a remote debug session. This recording may then be
2730 replayed back to gdb using "gdbreplay". See gdbserver/README for
2731 details. This is useful when you have a problem with GDB while doing
2732 remote debugging; you can make a recording of the session and send it
2733 to someone else, who can then recreate the problem.
2735 * Speedups for remote debugging
2737 GDB includes speedups for downloading and stepping MIPS systems using
2738 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2739 and more efficient S-record downloading.
2741 * Memory use reductions and statistics collection
2743 GDB now uses less memory and reports statistics about memory usage.
2744 Try the `maint print statistics' command, for example.
2746 *** Changes in GDB-4.15:
2748 * Psymtabs for XCOFF
2750 The symbol reader for AIX GDB now uses partial symbol tables. This
2751 can greatly improve startup time, especially for large executables.
2753 * Remote targets use caching
2755 Remote targets now use a data cache to speed up communication with the
2756 remote side. The data cache could lead to incorrect results because
2757 it doesn't know about volatile variables, thus making it impossible to
2758 debug targets which use memory mapped I/O devices. `set remotecache
2759 off' turns the the data cache off.
2761 * Remote targets may have threads
2763 The standard remote protocol now includes support for multiple threads
2764 in the target system, using new protocol commands 'H' and 'T'. See
2765 gdb/remote.c for details.
2769 If GDB is configured with `--enable-netrom', then it will include
2770 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2771 acts as though it is a bank of ROM on the target board, but you can
2772 write into it over the network. GDB's support consists only of
2773 support for fast loading into the emulated ROM; to debug, you must use
2774 another protocol, such as standard remote protocol. The usual
2775 sequence is something like
2777 target nrom <netrom-hostname>
2779 target remote <netrom-hostname>:1235
2783 GDB now includes support for the Apple Macintosh, as a host only. It
2784 may be run as either an MPW tool or as a standalone application, and
2785 it can debug through the serial port. All the usual GDB commands are
2786 available, but to the target command, you must supply "serial" as the
2787 device type instead of "/dev/ttyXX". See mpw-README in the main
2788 directory for more information on how to build. The MPW configuration
2789 scripts */mpw-config.in support only a few targets, and only the
2790 mips-idt-ecoff target has been tested.
2794 GDB configuration now uses autoconf. This is not user-visible,
2795 but does simplify configuration and building.
2799 GDB now supports hpux10.
2801 *** Changes in GDB-4.14:
2803 * New native configurations
2805 x86 FreeBSD i[345]86-*-freebsd
2806 x86 NetBSD i[345]86-*-netbsd
2807 NS32k NetBSD ns32k-*-netbsd
2808 Sparc NetBSD sparc-*-netbsd
2812 A29K VxWorks a29k-*-vxworks
2813 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2814 CPU32 EST-300 emulator m68*-*-est*
2815 PowerPC ELF powerpc-*-elf
2818 * Alpha OSF/1 support for procfs
2820 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2821 possible to attach to running processes. As the mounting of the /proc
2822 filesystem is optional on the Alpha, GDB automatically determines
2823 the availability of /proc during startup. This can lead to problems
2824 if /proc is unmounted after GDB has been started.
2826 * Arguments to user-defined commands
2828 User commands may accept up to 10 arguments separated by whitespace.
2829 Arguments are accessed within the user command via $arg0..$arg9. A
2832 print $arg0 + $arg1 + $arg2
2834 To execute the command use:
2837 Defines the command "adder" which prints the sum of its three arguments.
2838 Note the arguments are text substitutions, so they may reference variables,
2839 use complex expressions, or even perform inferior function calls.
2841 * New `if' and `while' commands
2843 This makes it possible to write more sophisticated user-defined
2844 commands. Both commands take a single argument, which is the
2845 expression to evaluate, and must be followed by the commands to
2846 execute, one per line, if the expression is nonzero, the list being
2847 terminated by the word `end'. The `if' command list may include an
2848 `else' word, which causes the following commands to be executed only
2849 if the expression is zero.
2851 * Fortran source language mode
2853 GDB now includes partial support for Fortran 77. It will recognize
2854 Fortran programs and can evaluate a subset of Fortran expressions, but
2855 variables and functions may not be handled correctly. GDB will work
2856 with G77, but does not yet know much about symbols emitted by other
2859 * Better HPUX support
2861 Most debugging facilities now work on dynamic executables for HPPAs
2862 running hpux9 or later. You can attach to running dynamically linked
2863 processes, but by default the dynamic libraries will be read-only, so
2864 for instance you won't be able to put breakpoints in them. To change
2865 that behavior do the following before running the program:
2871 This will cause the libraries to be mapped private and read-write.
2872 To revert to the normal behavior, do this:
2878 You cannot set breakpoints or examine data in the library until after
2879 the library is loaded if the function/data symbols do not have
2882 GDB can now also read debug symbols produced by the HP C compiler on
2883 HPPAs (sorry, no C++, Fortran or 68k support).
2885 * Target byte order now dynamically selectable
2887 You can choose which byte order to use with a target system, via the
2888 commands "set endian big" and "set endian little", and you can see the
2889 current setting by using "show endian". You can also give the command
2890 "set endian auto", in which case GDB will use the byte order
2891 associated with the executable. Currently, only embedded MIPS
2892 configurations support dynamic selection of target byte order.
2894 * New DOS host serial code
2896 This version uses DPMI interrupts to handle buffered I/O, so you
2897 no longer need to run asynctsr when debugging boards connected to
2900 *** Changes in GDB-4.13:
2902 * New "complete" command
2904 This lists all the possible completions for the rest of the line, if it
2905 were to be given as a command itself. This is intended for use by emacs.
2907 * Trailing space optional in prompt
2909 "set prompt" no longer adds a space for you after the prompt you set. This
2910 allows you to set a prompt which ends in a space or one that does not.
2912 * Breakpoint hit counts
2914 "info break" now displays a count of the number of times the breakpoint
2915 has been hit. This is especially useful in conjunction with "ignore"; you
2916 can ignore a large number of breakpoint hits, look at the breakpoint info
2917 to see how many times the breakpoint was hit, then run again, ignoring one
2918 less than that number, and this will get you quickly to the last hit of
2921 * Ability to stop printing at NULL character
2923 "set print null-stop" will cause GDB to stop printing the characters of
2924 an array when the first NULL is encountered. This is useful when large
2925 arrays actually contain only short strings.
2927 * Shared library breakpoints
2929 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2930 breakpoints in shared libraries before the executable is run.
2932 * Hardware watchpoints
2934 There is a new hardware breakpoint for the watch command for sparclite
2935 targets. See gdb/sparclite/hw_breakpoint.note.
2937 Hardware watchpoints are also now supported under GNU/Linux.
2941 Annotations have been added. These are for use with graphical interfaces,
2942 and are still experimental. Currently only gdba.el uses these.
2944 * Improved Irix 5 support
2946 GDB now works properly with Irix 5.2.
2948 * Improved HPPA support
2950 GDB now works properly with the latest GCC and GAS.
2952 * New native configurations
2954 Sequent PTX4 i[34]86-sequent-ptx4
2955 HPPA running OSF/1 hppa*-*-osf*
2956 Atari TT running SVR4 m68*-*-sysv4*
2957 RS/6000 LynxOS rs6000-*-lynxos*
2961 OS/9000 i[34]86-*-os9k
2962 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2965 * Hitachi SH7000 and E7000-PC ICE support
2967 There is now support for communicating with the Hitachi E7000-PC ICE.
2968 This is available automatically when GDB is configured for the SH.
2972 As usual, a variety of small fixes and improvements, both generic
2973 and configuration-specific. See the ChangeLog for more detail.
2975 *** Changes in GDB-4.12:
2977 * Irix 5 is now supported
2981 GDB-4.12 on the HPPA has a number of changes which make it unable
2982 to debug the output from the currently released versions of GCC and
2983 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2984 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2985 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2988 *** Changes in GDB-4.11:
2990 * User visible changes:
2994 The "set remotedebug" option is now consistent between the mips remote
2995 target, remote targets using the gdb-specific protocol, UDI (AMD's
2996 debug protocol for the 29k) and the 88k bug monitor. It is now an
2997 integer specifying a debug level (normally 0 or 1, but 2 means more
2998 debugging info for the mips target).
3000 * DEC Alpha native support
3002 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3003 debug info, but GDB works fairly well with the DEC compiler and should
3004 work with a future GCC release. See the README file for a few
3005 Alpha-specific notes.
3007 * Preliminary thread implementation
3009 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3011 * LynxOS native and target support for 386
3013 This release has been hosted on LynxOS 2.2, and also can be configured
3014 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3017 * Improvements in C++ mangling/demangling.
3019 This release has much better g++ debugging, specifically in name
3020 mangling/demangling, virtual function calls, print virtual table,
3021 call methods, ...etc.
3023 *** Changes in GDB-4.10:
3025 * User visible changes:
3027 Remote debugging using the GDB-specific (`target remote') protocol now
3028 supports the `load' command. This is only useful if you have some
3029 other way of getting the stub to the target system, and you can put it
3030 somewhere in memory where it won't get clobbered by the download.
3032 Filename completion now works.
3034 When run under emacs mode, the "info line" command now causes the
3035 arrow to point to the line specified. Also, "info line" prints
3036 addresses in symbolic form (as well as hex).
3038 All vxworks based targets now support a user settable option, called
3039 vxworks-timeout. This option represents the number of seconds gdb
3040 should wait for responses to rpc's. You might want to use this if
3041 your vxworks target is, perhaps, a slow software simulator or happens
3042 to be on the far side of a thin network line.
3046 This release contains support for using a DEC alpha as a GDB host for
3047 cross debugging. Native alpha debugging is not supported yet.
3050 *** Changes in GDB-4.9:
3054 This is the first GDB release which is accompanied by a matching testsuite.
3055 The testsuite requires installation of dejagnu, which should be available
3056 via ftp from most sites that carry GNU software.
3060 'Cfront' style demangling has had its name changed to 'ARM' style, to
3061 emphasize that it was written from the specifications in the C++ Annotated
3062 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3063 disclaimers, it still generated too much confusion with users attempting to
3064 use gdb with AT&T cfront.
3068 GDB now uses a standard remote interface to a simulator library.
3069 So far, the library contains simulators for the Zilog Z8001/2, the
3070 Hitachi H8/300, H8/500 and Super-H.
3072 * New targets supported
3074 H8/300 simulator h8300-hitachi-hms or h8300hms
3075 H8/500 simulator h8500-hitachi-hms or h8500hms
3076 SH simulator sh-hitachi-hms or sh
3077 Z8000 simulator z8k-zilog-none or z8ksim
3078 IDT MIPS board over serial line mips-idt-ecoff
3080 Cross-debugging to GO32 targets is supported. It requires a custom
3081 version of the i386-stub.c module which is integrated with the
3082 GO32 memory extender.
3084 * New remote protocols
3086 MIPS remote debugging protocol.
3088 * New source languages supported
3090 This version includes preliminary support for Chill, a Pascal like language
3091 used by telecommunications companies. Chill support is also being integrated
3092 into the GNU compiler, but we don't know when it will be publically available.
3095 *** Changes in GDB-4.8:
3097 * HP Precision Architecture supported
3099 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3100 version of this support was available as a set of patches from the
3101 University of Utah. GDB does not support debugging of programs
3102 compiled with the HP compiler, because HP will not document their file
3103 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3104 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3106 Many problems in the preliminary version have been fixed.
3108 * Faster and better demangling
3110 We have improved template demangling and fixed numerous bugs in the GNU style
3111 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3112 character types (wchar_t) are now supported. Demangling of each symbol is now
3113 only done once, and is cached when the symbol table for a file is read in.
3114 This results in a small increase in memory usage for C programs, a moderate
3115 increase in memory usage for C++ programs, and a fantastic speedup in
3118 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3119 from the specifications in the Annotated Reference Manual, which AT&T's
3120 compiler does not actually implement.
3122 * G++ multiple inheritance compiler problem
3124 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3125 inheritance lattices was reworked to properly discover ambiguities. We
3126 recently found an example which causes this new algorithm to fail in a
3127 very subtle way, producing bad debug information for those classes.
3128 The file 'gcc.patch' (in this directory) can be applied to gcc to
3129 circumvent the problem. A future GCC release will contain a complete
3132 The previous G++ debug info problem (mentioned below for the gdb-4.7
3133 release) is fixed in gcc version 2.3.2.
3135 * Improved configure script
3137 The `configure' script will now attempt to guess your system type if
3138 you don't supply a host system type. The old scheme of supplying a
3139 host system triplet is preferable over using this. All the magic is
3140 done in the new `config.guess' script. Examine it for details.
3142 We have also brought our configure script much more in line with the FSF's
3143 version. It now supports the --with-xxx options. In particular,
3144 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3145 The resulting GDB will not be able to read arbitrary object file formats --
3146 only the format ``expected'' to be used on the configured target system.
3147 We hope to make this the default in a future release.
3149 * Documentation improvements
3151 There's new internal documentation on how to modify GDB, and how to
3152 produce clean changes to the code. We implore people to read it
3153 before submitting changes.
3155 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3156 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3157 `info' files are also provided. To build `info' files from scratch,
3158 you will need the latest `makeinfo' release, which will be available in
3159 a future texinfo-X.Y release.
3161 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3162 We're not sure exactly which versions have this problem, but it has
3163 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3164 or better. If that isn't possible, there is a patch in
3165 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3166 around this problem.
3170 GDB now supports array constants that can be used in expressions typed in by
3171 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3172 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3175 The new directory `gdb/sparclite' contains a program that demonstrates
3176 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3178 * New native hosts supported
3180 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3181 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3183 * New targets supported
3185 AMD 29k family via UDI a29k-amd-udi or udi29k
3187 * New file formats supported
3189 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3190 HPUX core files, and SCO 3.2v2 core files.
3194 Attaching to processes now works again; thanks for the many bug reports.
3196 We have also stomped on a bunch of core dumps caused by
3197 printf_filtered("%s") problems.
3199 We eliminated a copyright problem on the rpc and ptrace header files
3200 for VxWorks, which was discovered at the last minute during the 4.7
3201 release. You should now be able to build a VxWorks GDB.
3203 You can now interrupt gdb while an attached process is running. This
3204 will cause the attached process to stop, and give control back to GDB.
3206 We fixed problems caused by using too many file descriptors
3207 for reading symbols from object files and libraries. This was
3208 especially a problem for programs that used many (~100) shared
3211 The `step' command now only enters a subroutine if there is line number
3212 information for the subroutine. Otherwise it acts like the `next'
3213 command. Previously, `step' would enter subroutines if there was
3214 any debugging information about the routine. This avoids problems
3215 when using `cc -g1' on MIPS machines.
3217 * Internal improvements
3219 GDB's internal interfaces have been improved to make it easier to support
3220 debugging of multiple languages in the future.
3222 GDB now uses a common structure for symbol information internally.
3223 Minimal symbols (derived from linkage symbols in object files), partial
3224 symbols (from a quick scan of debug information), and full symbols
3225 contain a common subset of information, making it easier to write
3226 shared code that handles any of them.
3228 * New command line options
3230 We now accept --silent as an alias for --quiet.
3234 The memory-mapped-malloc library is now licensed under the GNU Library
3235 General Public License.
3237 *** Changes in GDB-4.7:
3239 * Host/native/target split
3241 GDB has had some major internal surgery to untangle the support for
3242 hosts and remote targets. Now, when you configure GDB for a remote
3243 target, it will no longer load in all of the support for debugging
3244 local programs on the host. When fully completed and tested, this will
3245 ensure that arbitrary host/target combinations are possible.
3247 The primary conceptual shift is to separate the non-portable code in
3248 GDB into three categories. Host specific code is required any time GDB
3249 is compiled on that host, regardless of the target. Target specific
3250 code relates to the peculiarities of the target, but can be compiled on
3251 any host. Native specific code is everything else: it can only be
3252 built when the host and target are the same system. Child process
3253 handling and core file support are two common `native' examples.
3255 GDB's use of /proc for controlling Unix child processes is now cleaner.
3256 It has been split out into a single module under the `target_ops' vector,
3257 plus two native-dependent functions for each system that uses /proc.
3259 * New hosts supported
3261 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3262 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3263 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3265 * New targets supported
3267 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3268 68030 and CPU32 m68030-*-*, m68332-*-*
3270 * New native hosts supported
3272 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3273 (386bsd is not well tested yet)
3274 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3276 * New file formats supported
3278 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3279 supports reading of `a.out.adobe' object files, which are an a.out
3280 format extended with minimal information about multiple sections.
3284 `show copying' is the same as the old `info copying'.
3285 `show warranty' is the same as `info warrantee'.
3286 These were renamed for consistency. The old commands continue to work.
3288 `info handle' is a new alias for `info signals'.
3290 You can now define pre-command hooks, which attach arbitrary command
3291 scripts to any command. The commands in the hook will be executed
3292 prior to the user's command. You can also create a hook which will be
3293 executed whenever the program stops. See gdb.texinfo.
3297 We now deal with Cfront style name mangling, and can even extract type
3298 info from mangled symbols. GDB can automatically figure out which
3299 symbol mangling style your C++ compiler uses.
3301 Calling of methods and virtual functions has been improved as well.
3305 The crash that occured when debugging Sun Ansi-C compiled binaries is
3306 fixed. This was due to mishandling of the extra N_SO stabs output
3309 We also finally got Ultrix 4.2 running in house, and fixed core file
3310 support, with help from a dozen people on the net.
3312 John M. Farrell discovered that the reason that single-stepping was so
3313 slow on all of the Mips based platforms (primarily SGI and DEC) was
3314 that we were trying to demangle and lookup a symbol used for internal
3315 purposes on every instruction that was being stepped through. Changing
3316 the name of that symbol so that it couldn't be mistaken for a C++
3317 mangled symbol sped things up a great deal.
3319 Rich Pixley sped up symbol lookups in general by getting much smarter
3320 about when C++ symbol mangling is necessary. This should make symbol
3321 completion (TAB on the command line) much faster. It's not as fast as
3322 we'd like, but it's significantly faster than gdb-4.6.
3326 A new user controllable variable 'call_scratch_address' can
3327 specify the location of a scratch area to be used when GDB
3328 calls a function in the target. This is necessary because the
3329 usual method of putting the scratch area on the stack does not work
3330 in systems that have separate instruction and data spaces.
3332 We integrated changes to support the 29k UDI (Universal Debugger
3333 Interface), but discovered at the last minute that we didn't have all
3334 of the appropriate copyright paperwork. We are working with AMD to
3335 resolve this, and hope to have it available soon.
3339 We have sped up the remote serial line protocol, especially for targets
3340 with lots of registers. It now supports a new `expedited status' ('T')
3341 message which can be used in place of the existing 'S' status message.
3342 This allows the remote stub to send only the registers that GDB
3343 needs to make a quick decision about single-stepping or conditional
3344 breakpoints, eliminating the need to fetch the entire register set for
3345 each instruction being stepped through.
3347 The GDB remote serial protocol now implements a write-through cache for
3348 registers, only re-reading the registers if the target has run.
3350 There is also a new remote serial stub for SPARC processors. You can
3351 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3352 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3353 processor with a serial port.
3357 Configure.in files have become much easier to read and modify. A new
3358 `table driven' format makes it more obvious what configurations are
3359 supported, and what files each one uses.
3363 There is a new opcodes library which will eventually contain all of the
3364 disassembly routines and opcode tables. At present, it only contains
3365 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3366 disassembler (binutils/objdump) to share these routines.
3368 The libiberty library is now copylefted under the GNU Library General
3369 Public License. This allows more liberal use, and was done so libg++
3370 can use it. This makes no difference to GDB, since the Library License
3371 grants all the rights from the General Public License.
3375 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3376 reference to the stabs symbol info used by the debugger. It is (as far
3377 as we know) the only published document on this fascinating topic. We
3378 encourage you to read it, compare it to the stabs information on your
3379 system, and send improvements on the document in general (to
3380 bug-gdb@prep.ai.mit.edu).
3382 And, of course, many bugs have been fixed.
3385 *** Changes in GDB-4.6:
3387 * Better support for C++ function names
3389 GDB now accepts as input the "demangled form" of C++ overloaded function
3390 names and member function names, and can do command completion on such names
3391 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3392 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3393 Make use of command completion, it is your friend.
3395 GDB also now accepts a variety of C++ mangled symbol formats. They are
3396 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3397 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3398 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3399 for the list of formats.
3401 * G++ symbol mangling problem
3403 Recent versions of gcc have a bug in how they emit debugging information for
3404 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3405 directory) can be applied to gcc to fix the problem. Alternatively, if you
3406 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3407 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3408 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3411 * New 'maintenance' command
3413 All of the commands related to hacking GDB internals have been moved out of
3414 the main command set, and now live behind the 'maintenance' command. This
3415 can also be abbreviated as 'mt'. The following changes were made:
3417 dump-me -> maintenance dump-me
3418 info all-breakpoints -> maintenance info breakpoints
3419 printmsyms -> maintenance print msyms
3420 printobjfiles -> maintenance print objfiles
3421 printpsyms -> maintenance print psymbols
3422 printsyms -> maintenance print symbols
3424 The following commands are new:
3426 maintenance demangle Call internal GDB demangler routine to
3427 demangle a C++ link name and prints the result.
3428 maintenance print type Print a type chain for a given symbol
3430 * Change to .gdbinit file processing
3432 We now read the $HOME/.gdbinit file before processing the argv arguments
3433 (e.g. reading symbol files or core files). This allows global parameters to
3434 be set, which will apply during the symbol reading. The ./.gdbinit is still
3435 read after argv processing.
3437 * New hosts supported
3439 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3441 GNU/Linux support i386-unknown-linux or linux
3443 We are also including code to support the HP/PA running BSD and HPUX. This
3444 is almost guaranteed not to work, as we didn't have time to test or build it
3445 for this release. We are including it so that the more adventurous (or
3446 masochistic) of you can play with it. We also had major problems with the
3447 fact that the compiler that we got from HP doesn't support the -g option.
3450 * New targets supported
3452 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3454 * More smarts about finding #include files
3456 GDB now remembers the compilation directory for all include files, and for
3457 all files from which C is generated (like yacc and lex sources). This
3458 greatly improves GDB's ability to find yacc/lex sources, and include files,
3459 especially if you are debugging your program from a directory different from
3460 the one that contains your sources.
3462 We also fixed a bug which caused difficulty with listing and setting
3463 breakpoints in include files which contain C code. (In the past, you had to
3464 try twice in order to list an include file that you hadn't looked at before.)
3466 * Interesting infernals change
3468 GDB now deals with arbitrary numbers of sections, where the symbols for each
3469 section must be relocated relative to that section's landing place in the
3470 target's address space. This work was needed to support ELF with embedded
3471 stabs used by Solaris-2.0.
3473 * Bug fixes (of course!)
3475 There have been loads of fixes for the following things:
3476 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3477 i960, stabs, DOS(GO32), procfs, etc...
3479 See the ChangeLog for details.
3481 *** Changes in GDB-4.5:
3483 * New machines supported (host and target)
3485 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3487 SGI Irix-4.x mips-sgi-irix4 or iris4
3489 * New malloc package
3491 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3492 Mmalloc is capable of handling mutiple heaps of memory. It is also
3493 capable of saving a heap to a file, and then mapping it back in later.
3494 This can be used to greatly speedup the startup of GDB by using a
3495 pre-parsed symbol table which lives in a mmalloc managed heap. For
3496 more details, please read mmalloc/mmalloc.texi.
3500 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3501 'help info proc' for details.
3503 * MIPS ecoff symbol table format
3505 The code that reads MIPS symbol table format is now supported on all hosts.
3506 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3509 * File name changes for MS-DOS
3511 Many files in the config directories have been renamed to make it easier to
3512 support GDB on MS-DOSe systems (which have very restrictive file name
3513 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3514 environment) is close to working but has some remaining problems. Note
3515 that debugging of DOS programs is not supported, due to limitations
3516 in the ``operating system'', but it can be used to host cross-debugging.
3518 * Cross byte order fixes
3520 Many fixes have been made to support cross debugging of Sparc and MIPS
3521 targets from hosts whose byte order differs.
3523 * New -mapped and -readnow options
3525 If memory-mapped files are available on your system through the 'mmap'
3526 system call, you can use the -mapped option on the `file' or
3527 `symbol-file' commands to cause GDB to write the symbols from your
3528 program into a reusable file. If the program you are debugging is
3529 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3530 Future GDB debugging sessions will notice the presence of this file,
3531 and will quickly map in symbol information from it, rather than reading
3532 the symbol table from the executable program. Using the '-mapped'
3533 option in a GDB `file' or `symbol-file' command has the same effect as
3534 starting GDB with the '-mapped' command-line option.
3536 You can cause GDB to read the entire symbol table immediately by using
3537 the '-readnow' option with any of the commands that load symbol table
3538 information (or on the GDB command line). This makes the command
3539 slower, but makes future operations faster.
3541 The -mapped and -readnow options are typically combined in order to
3542 build a `fred.syms' file that contains complete symbol information.
3543 A simple GDB invocation to do nothing but build a `.syms' file for future
3546 gdb -batch -nx -mapped -readnow programname
3548 The `.syms' file is specific to the host machine on which GDB is run.
3549 It holds an exact image of GDB's internal symbol table. It cannot be
3550 shared across multiple host platforms.
3552 * longjmp() handling
3554 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3555 siglongjmp() without losing control. This feature has not yet been ported to
3556 all systems. It currently works on many 386 platforms, all MIPS-based
3557 platforms (SGI, DECstation, etc), and Sun3/4.
3561 Preliminary work has been put in to support the new Solaris OS from Sun. At
3562 this time, it can control and debug processes, but it is not capable of
3567 As always, many many bug fixes. The major areas were with g++, and mipsread.
3568 People using the MIPS-based platforms should experience fewer mysterious
3569 crashes and trashed symbol tables.
3571 *** Changes in GDB-4.4:
3573 * New machines supported (host and target)
3575 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3577 BSD Reno on Vax vax-dec-bsd
3578 Ultrix on Vax vax-dec-ultrix
3580 * New machines supported (target)
3582 AMD 29000 embedded, using EBMON a29k-none-none
3586 GDB continues to improve its handling of C++. `References' work better.
3587 The demangler has also been improved, and now deals with symbols mangled as
3588 per the Annotated C++ Reference Guide.
3590 GDB also now handles `stabs' symbol information embedded in MIPS
3591 `ecoff' symbol tables. Since the ecoff format was not easily
3592 extensible to handle new languages such as C++, this appeared to be a
3593 good way to put C++ debugging info into MIPS binaries. This option
3594 will be supported in the GNU C compiler, version 2, when it is
3597 * New features for SVR4
3599 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3600 shared libraries. Debugging dynamically linked programs should present
3601 only minor differences from debugging statically linked programs.
3603 The `info proc' command will print out information about any process
3604 on an SVR4 system (including the one you are debugging). At the moment,
3605 it prints the address mappings of the process.
3607 If you bring up GDB on another SVR4 system, please send mail to
3608 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3610 * Better dynamic linking support in SunOS
3612 Reading symbols from shared libraries which contain debugging symbols
3613 now works properly. However, there remain issues such as automatic
3614 skipping of `transfer vector' code during function calls, which
3615 make it harder to debug code in a shared library, than to debug the
3616 same code linked statically.
3620 GDB is now using the latest `getopt' routines from the FSF. This
3621 version accepts the -- prefix for options with long names. GDB will
3622 continue to accept the old forms (-option and +option) as well.
3623 Various single letter abbreviations for options have been explicity
3624 added to the option table so that they won't get overshadowed in the
3625 future by other options that begin with the same letter.
3629 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3630 Many assorted bugs have been handled. Many more remain to be handled.
3631 See the various ChangeLog files (primarily in gdb and bfd) for details.
3634 *** Changes in GDB-4.3:
3636 * New machines supported (host and target)
3638 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3639 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3640 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3642 * Almost SCO Unix support
3644 We had hoped to support:
3645 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3646 (except for core file support), but we discovered very late in the release
3647 that it has problems with process groups that render gdb unusable. Sorry
3648 about that. I encourage people to fix it and post the fixes.
3650 * Preliminary ELF and DWARF support
3652 GDB can read ELF object files on System V Release 4, and can handle
3653 debugging records for C, in DWARF format, in ELF files. This support
3654 is preliminary. If you bring up GDB on another SVR4 system, please
3655 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3660 GDB now uses the latest `readline' library. One user-visible change
3661 is that two tabs will list possible command completions, which previously
3662 required typing M-? (meta-question mark, or ESC ?).
3666 The `stepi' bug that many of you noticed has been squashed.
3667 Many bugs in C++ have been handled. Many more remain to be handled.
3668 See the various ChangeLog files (primarily in gdb and bfd) for details.
3670 * State of the MIPS world (in case you wondered):
3672 GDB can understand the symbol tables emitted by the compilers
3673 supplied by most vendors of MIPS-based machines, including DEC. These
3674 symbol tables are in a format that essentially nobody else uses.
3676 Some versions of gcc come with an assembler post-processor called
3677 mips-tfile. This program is required if you want to do source-level
3678 debugging of gcc-compiled programs. I believe FSF does not ship
3679 mips-tfile with gcc version 1, but it will eventually come with gcc
3682 Debugging of g++ output remains a problem. g++ version 1.xx does not
3683 really support it at all. (If you're lucky, you should be able to get
3684 line numbers and stack traces to work, but no parameters or local
3685 variables.) With some work it should be possible to improve the
3688 When gcc version 2 is released, you will have somewhat better luck.
3689 However, even then you will get confusing results for inheritance and
3692 We will eventually provide full debugging of g++ output on
3693 DECstations. This will probably involve some kind of stabs-in-ecoff
3694 encapulation, but the details have not been worked out yet.
3697 *** Changes in GDB-4.2:
3699 * Improved configuration
3701 Only one copy of `configure' exists now, and it is not self-modifying.
3702 Porting BFD is simpler.
3706 The `step' and `next' commands now only stop at the first instruction
3707 of a source line. This prevents the multiple stops that used to occur
3708 in switch statements, for-loops, etc. `Step' continues to stop if a
3709 function that has debugging information is called within the line.
3713 Lots of small bugs fixed. More remain.
3715 * New host supported (not target)
3717 Intel 386 PC clone running Mach i386-none-mach
3720 *** Changes in GDB-4.1:
3722 * Multiple source language support
3724 GDB now has internal scaffolding to handle several source languages.
3725 It determines the type of each source file from its filename extension,
3726 and will switch expression parsing and number formatting to match the
3727 language of the function in the currently selected stack frame.
3728 You can also specifically set the language to be used, with
3729 `set language c' or `set language modula-2'.
3733 GDB now has preliminary support for the GNU Modula-2 compiler,
3734 currently under development at the State University of New York at
3735 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3736 continue through the fall of 1991 and into 1992.
3738 Other Modula-2 compilers are currently not supported, and attempting to
3739 debug programs compiled with them will likely result in an error as the
3740 symbol table is read. Feel free to work on it, though!
3742 There are hooks in GDB for strict type checking and range checking,
3743 in the `Modula-2 philosophy', but they do not currently work.
3747 GDB can now write to executable and core files (e.g. patch
3748 a variable's value). You must turn this switch on, specify
3749 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3750 by assigning a new value to a variable. Modifications take
3753 * Automatic SunOS shared library reading
3755 When you run your program, GDB automatically determines where its
3756 shared libraries (if any) have been loaded, and reads their symbols.
3757 The `share' command is no longer needed. This also works when
3758 examining core files.
3762 You can specify the number of lines that the `list' command shows.
3765 * New machines supported (host and target)
3767 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3768 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3769 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3771 * New hosts supported (not targets)
3773 IBM RT/PC: romp-ibm-aix or rtpc
3775 * New targets supported (not hosts)
3777 AMD 29000 embedded with COFF a29k-none-coff
3778 AMD 29000 embedded with a.out a29k-none-aout
3779 Ultracomputer remote kernel debug a29k-nyu-kern
3781 * New remote interfaces
3787 *** Changes in GDB-4.0:
3791 Wide output is wrapped at good places to make the output more readable.
3793 Gdb now supports cross-debugging from a host machine of one type to a
3794 target machine of another type. Communication with the target system
3795 is over serial lines. The ``target'' command handles connecting to the
3796 remote system; the ``load'' command will download a program into the
3797 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3798 also supports debugging of realtime processes running under VxWorks,
3799 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3800 stub on the target system.
3802 New CPUs supported include the AMD 29000 and Intel 960.
3804 GDB now reads object files and symbol tables via a ``binary file''
3805 library, which allows a single copy of GDB to debug programs of multiple
3806 object file types such as a.out and coff.
3808 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3809 refcard.dvi and refcard.ps are available to format it).
3812 * Control-Variable user interface simplified
3814 All variables that control the operation of the debugger can be set
3815 by the ``set'' command, and displayed by the ``show'' command.
3817 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3818 ``Show prompt'' produces the response:
3819 Gdb's prompt is new-gdb=>.
3821 What follows are the NEW set commands. The command ``help set'' will
3822 print a complete list of old and new set commands. ``help set FOO''
3823 will give a longer description of the variable FOO. ``show'' will show
3824 all of the variable descriptions and their current settings.
3826 confirm on/off: Enables warning questions for operations that are
3827 hard to recover from, e.g. rerunning the program while
3828 it is already running. Default is ON.
3830 editing on/off: Enables EMACS style command line editing
3831 of input. Previous lines can be recalled with
3832 control-P, the current line can be edited with control-B,
3833 you can search for commands with control-R, etc.
3836 history filename NAME: NAME is where the gdb command history
3837 will be stored. The default is .gdb_history,
3838 or the value of the environment variable
3841 history size N: The size, in commands, of the command history. The
3842 default is 256, or the value of the environment variable
3845 history save on/off: If this value is set to ON, the history file will
3846 be saved after exiting gdb. If set to OFF, the
3847 file will not be saved. The default is OFF.
3849 history expansion on/off: If this value is set to ON, then csh-like
3850 history expansion will be performed on
3851 command line input. The default is OFF.
3853 radix N: Sets the default radix for input and output. It can be set
3854 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3855 in the current radix, so "set radix 10" is always a no-op.
3857 height N: This integer value is the number of lines on a page. Default
3858 is 24, the current `stty rows'' setting, or the ``li#''
3859 setting from the termcap entry matching the environment
3862 width N: This integer value is the number of characters on a line.
3863 Default is 80, the current `stty cols'' setting, or the ``co#''
3864 setting from the termcap entry matching the environment
3867 Note: ``set screensize'' is obsolete. Use ``set height'' and
3868 ``set width'' instead.
3870 print address on/off: Print memory addresses in various command displays,
3871 such as stack traces and structure values. Gdb looks
3872 more ``symbolic'' if you turn this off; it looks more
3873 ``machine level'' with it on. Default is ON.
3875 print array on/off: Prettyprint arrays. New convenient format! Default
3878 print demangle on/off: Print C++ symbols in "source" form if on,
3881 print asm-demangle on/off: Same, for assembler level printouts
3884 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3887 * Support for Epoch Environment.
3889 The epoch environment is a version of Emacs v18 with windowing. One
3890 new command, ``inspect'', is identical to ``print'', except that if you
3891 are running in the epoch environment, the value is printed in its own
3895 * Support for Shared Libraries
3897 GDB can now debug programs and core files that use SunOS shared libraries.
3898 Symbols from a shared library cannot be referenced
3899 before the shared library has been linked with the program (this
3900 happens after you type ``run'' and before the function main() is entered).
3901 At any time after this linking (including when examining core files
3902 from dynamically linked programs), gdb reads the symbols from each
3903 shared library when you type the ``sharedlibrary'' command.
3904 It can be abbreviated ``share''.
3906 sharedlibrary REGEXP: Load shared object library symbols for files
3907 matching a unix regular expression. No argument
3908 indicates to load symbols for all shared libraries.
3910 info sharedlibrary: Status of loaded shared libraries.
3915 A watchpoint stops execution of a program whenever the value of an
3916 expression changes. Checking for this slows down execution
3917 tremendously whenever you are in the scope of the expression, but is
3918 quite useful for catching tough ``bit-spreader'' or pointer misuse
3919 problems. Some machines such as the 386 have hardware for doing this
3920 more quickly, and future versions of gdb will use this hardware.
3922 watch EXP: Set a watchpoint (breakpoint) for an expression.
3924 info watchpoints: Information about your watchpoints.
3926 delete N: Deletes watchpoint number N (same as breakpoints).
3927 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3928 enable N: Re-enables watchpoint number N (same as breakpoints).
3931 * C++ multiple inheritance
3933 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3936 * C++ exception handling
3938 Gdb now supports limited C++ exception handling. Besides the existing
3939 ability to breakpoint on an exception handler, gdb can breakpoint on
3940 the raising of an exception (before the stack is peeled back to the
3943 catch FOO: If there is a FOO exception handler in the dynamic scope,
3944 set a breakpoint to catch exceptions which may be raised there.
3945 Multiple exceptions (``catch foo bar baz'') may be caught.
3947 info catch: Lists all exceptions which may be caught in the
3948 current stack frame.
3951 * Minor command changes
3953 The command ``call func (arg, arg, ...)'' now acts like the print
3954 command, except it does not print or save a value if the function's result
3955 is void. This is similar to dbx usage.
3957 The ``up'' and ``down'' commands now always print the frame they end up
3958 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3959 frames without printing.
3961 * New directory command
3963 'dir' now adds directories to the FRONT of the source search path.
3964 The path starts off empty. Source files that contain debug information
3965 about the directory in which they were compiled can be found even
3966 with an empty path; Sun CC and GCC include this information. If GDB can't
3967 find your source file in the current directory, type "dir .".
3969 * Configuring GDB for compilation
3971 For normal use, type ``./configure host''. See README or gdb.texinfo
3974 GDB now handles cross debugging. If you are remotely debugging between
3975 two different machines, type ``./configure host -target=targ''.
3976 Host is the machine where GDB will run; targ is the machine
3977 where the program that you are debugging will run.