1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.1
6 * GDB now sends xmlRegisters= in qSupported packet to indicate that
7 it understands register description.
9 * The --batch flag now disables pagination and queries.
11 * X86 general purpose registers
13 GDB now supports reading/writing byte, word and double-word x86
14 general purpose registers directly. This means you can use, say,
15 $ah or $ax to refer, respectively, to the byte register AH and
16 16-bit word register AX that are actually portions of the 32-bit
17 register EAX or 64-bit register RAX.
19 * The `commands' command now accepts a range of breakpoints to modify.
20 A plain `commands' following an `rbreak' will affect all the
21 breakpoints set by `rbreak'.
25 ** The GDB Python API now has access to symbols, symbol tables, and
28 ** New methods gdb.target_charset and gdb.target_wide_charset.
30 * Tracepoint actions were unified with breakpoint commands. In particular,
31 there are no longer differences in "info break" output for breakpoints and
32 tracepoints and the "commands" command can be used for both tracepoints and
37 ARM Symbian arm*-*-symbianelf*
39 *** Changes in GDB 7.1
45 GDB now supports importing of namespaces in C++. This enables the
46 user to inspect variables from imported namespaces. Support for
47 namepace aliasing has also been added. So, if a namespace is
48 aliased in the current scope (e.g. namepace C=A; ) the user can
49 print variables using the alias (e.g. (gdb) print C::x).
53 All known bugs relating to the printing of virtual base class were
54 fixed. It is now possible to call overloaded static methods using a
59 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
60 and reinterpret_cast<> are now handled by the C++ expression parser.
64 Xilinx MicroBlaze microblaze-*-*
69 Xilinx MicroBlaze microblaze
72 * Multi-program debugging.
74 GDB now has support for multi-program (a.k.a. multi-executable or
75 multi-exec) debugging. This allows for debugging multiple inferiors
76 simultaneously each running a different program under the same GDB
77 session. See "Debugging Multiple Inferiors and Programs" in the
78 manual for more information. This implied some user visible changes
79 in the multi-inferior support. For example, "info inferiors" now
80 lists inferiors that are not running yet or that have exited
81 already. See also "New commands" and "New options" below.
83 * New tracing features
85 GDB's tracepoint facility now includes several new features:
87 ** Trace state variables
89 GDB tracepoints now include support for trace state variables, which
90 are variables managed by the target agent during a tracing
91 experiment. They are useful for tracepoints that trigger each
92 other, so for instance one tracepoint can count hits in a variable,
93 and then a second tracepoint has a condition that is true when the
94 count reaches a particular value. Trace state variables share the
95 $-syntax of GDB convenience variables, and can appear in both
96 tracepoint actions and condition expressions. Use the "tvariable"
97 command to create, and "info tvariables" to view; see "Trace State
98 Variables" in the manual for more detail.
102 GDB now includes an option for defining fast tracepoints, which
103 targets may implement more efficiently, such as by installing a jump
104 into the target agent rather than a trap instruction. The resulting
105 speedup can be by two orders of magnitude or more, although the
106 tradeoff is that some program locations on some target architectures
107 might not allow fast tracepoint installation, for instance if the
108 instruction to be replaced is shorter than the jump. To request a
109 fast tracepoint, use the "ftrace" command, with syntax identical to
110 the regular trace command.
112 ** Disconnected tracing
114 It is now possible to detach GDB from the target while it is running
115 a trace experiment, then reconnect later to see how the experiment
116 is going. In addition, a new variable disconnected-tracing lets you
117 tell the target agent whether to continue running a trace if the
118 connection is lost unexpectedly.
122 GDB now has the ability to save the trace buffer into a file, and
123 then use that file as a target, similarly to you can do with
124 corefiles. You can select trace frames, print data that was
125 collected in them, and use tstatus to display the state of the
126 tracing run at the moment that it was saved. To create a trace
127 file, use "tsave <filename>", and to use it, do "target tfile
130 ** Circular trace buffer
132 You can ask the target agent to handle the trace buffer as a
133 circular buffer, discarding the oldest trace frames to make room for
134 newer ones, by setting circular-trace-buffer to on. This feature may
135 not be available for all target agents.
140 The disassemble command, when invoked with two arguments, now requires
141 the arguments to be comma-separated.
144 The info variables command now displays variable definitions. Files
145 which only declare a variable are not shown.
148 The source command is now capable of sourcing Python scripts.
149 This feature is dependent on the debugger being build with Python
152 Related to this enhancement is also the introduction of a new command
153 "set script-extension" (see below).
155 * New commands (for set/show, see "New options" below)
157 record save [<FILENAME>]
158 Save a file (in core file format) containing the process record
159 execution log for replay debugging at a later time.
161 record restore <FILENAME>
162 Restore the process record execution log that was saved at an
163 earlier time, for replay debugging.
165 add-inferior [-copies <N>] [-exec <FILENAME>]
168 clone-inferior [-copies <N>] [ID]
169 Make a new inferior ready to execute the same program another
175 maint info program-spaces
176 List the program spaces loaded into GDB.
178 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
179 show remote interrupt-sequence
180 Allow the user to select one of ^C, a BREAK signal or BREAK-g
181 as the sequence to the remote target in order to interrupt the execution.
182 Ctrl-C is a default. Some system prefers BREAK which is high level of
183 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
184 Magic SysRq g. It is BREAK signal and character 'g'.
186 set remote interrupt-on-connect [on | off]
187 show remote interrupt-on-connect
188 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
189 remote target when gdb connects to it. This is needed when you debug
192 set remotebreak [on | off]
194 Deprecated. Use "set/show remote interrupt-sequence" instead.
196 tvariable $NAME [ = EXP ]
197 Create or modify a trace state variable.
200 List trace state variables and their values.
202 delete tvariable $NAME ...
203 Delete one or more trace state variables.
206 Evaluate the given expressions without collecting anything into the
207 trace buffer. (Valid in tracepoint actions only.)
209 ftrace FN / FILE:LINE / *ADDR
210 Define a fast tracepoint at the given function, line, or address.
212 * New expression syntax
214 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
215 GDB now parses 0b101010 identically with 42.
219 set follow-exec-mode new|same
220 show follow-exec-mode
221 Control whether GDB reuses the same inferior across an exec call or
222 creates a new one. This is useful to be able to restart the old
223 executable after the inferior having done an exec call.
225 set default-collect EXPR, ...
227 Define a list of expressions to be collected at each tracepoint.
228 This is a useful way to ensure essential items are not overlooked,
229 such as registers or a critical global variable.
231 set disconnected-tracing
232 show disconnected-tracing
233 If set to 1, the target is instructed to continue tracing if it
234 loses its connection to GDB. If 0, the target is to stop tracing
237 set circular-trace-buffer
238 show circular-trace-buffer
239 If set to on, the target is instructed to use a circular trace buffer
240 and discard the oldest trace frames instead of stopping the trace due
241 to a full trace buffer. If set to off, the trace stops when the buffer
242 fills up. Some targets may not support this.
244 set script-extension off|soft|strict
245 show script-extension
246 If set to "off", the debugger does not perform any script language
247 recognition, and all sourced files are assumed to be GDB scripts.
248 If set to "soft" (the default), files are sourced according to
249 filename extension, falling back to GDB scripts if the first
251 If set to "strict", files are sourced according to filename extension.
253 set ada trust-PAD-over-XVS on|off
254 show ada trust-PAD-over-XVS
255 If off, activate a workaround against a bug in the debugging information
256 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
257 the GCC sources for more information about the GNAT encoding and
258 PAD types in particular). It is always safe to set this option to
259 off, but this introduces a slight performance penalty. The default
262 * Python API Improvements
264 ** GDB provides the new class gdb.LazyString. This is useful in
265 some pretty-printing cases. The new method gdb.Value.lazy_string
266 provides a simple way to create objects of this type.
268 ** The fields returned by gdb.Type.fields now have an
269 `is_base_class' attribute.
271 ** The new method gdb.Type.range returns the range of an array type.
273 ** The new method gdb.parse_and_eval can be used to parse and
274 evaluate an expression.
279 Define a trace state variable.
282 Get the current value of a trace state variable.
285 Set desired tracing behavior upon disconnection.
288 Set the trace buffer to be linear or circular.
291 Get data about the tracepoints currently in use.
295 Process record now works correctly with hardware watchpoints.
297 Multiple bug fixes have been made to the mips-irix port, making it
298 much more reliable. In particular:
299 - Debugging threaded applications is now possible again. Previously,
300 GDB would hang while starting the program, or while waiting for
301 the program to stop at a breakpoint.
302 - Attaching to a running process no longer hangs.
303 - An error occurring while loading a core file has been fixed.
304 - Changing the value of the PC register now works again. This fixes
305 problems observed when using the "jump" command, or when calling
306 a function from GDB, or even when assigning a new value to $pc.
307 - With the "finish" and "return" commands, the return value for functions
308 returning a small array is now correctly printed.
309 - It is now possible to break on shared library code which gets executed
310 during a shared library init phase (code executed while executing
311 their .init section). Previously, the breakpoint would have no effect.
312 - GDB is now able to backtrace through the signal handler for
313 non-threaded programs.
315 PIE (Position Independent Executable) programs debugging is now supported.
316 This includes debugging execution of PIC (Position Independent Code) shared
317 libraries although for that, it should be possible to run such libraries as an
320 *** Changes in GDB 7.0
322 * GDB now has an interface for JIT compilation. Applications that
323 dynamically generate code can create symbol files in memory and register
324 them with GDB. For users, the feature should work transparently, and
325 for JIT developers, the interface is documented in the GDB manual in the
326 "JIT Compilation Interface" chapter.
328 * Tracepoints may now be conditional. The syntax is as for
329 breakpoints; either an "if" clause appended to the "trace" command,
330 or the "condition" command is available. GDB sends the condition to
331 the target for evaluation using the same bytecode format as is used
332 for tracepoint actions.
334 * "disassemble" command with a /r modifier, print the raw instructions
335 in hex as well as in symbolic form.
337 * Process record and replay
339 In a architecture environment that supports ``process record and
340 replay'', ``process record and replay'' target can record a log of
341 the process execution, and replay it with both forward and reverse
344 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
345 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
346 set execution-direction {forward|reverse}, for targets that support
349 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
350 feature is available with a native GDB running on kernel version
353 * GDB now has support for multi-byte and wide character sets on the
354 target. Strings whose character type is wchar_t, char16_t, or
355 char32_t are now correctly printed. GDB supports wide- and unicode-
356 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
357 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
358 `printf'. This feature requires iconv to work properly; if your
359 system does not have a working iconv, GDB can use GNU libiconv. See
360 the installation instructions for more information.
362 * GDB now supports automatic retrieval of shared library files from
363 remote targets. To use this feature, specify a system root that begins
364 with the `remote:' prefix, either via the `set sysroot' command or via
365 the `--with-sysroot' configure-time option.
367 * "info sharedlibrary" now takes an optional regex of libraries to show,
368 and it now reports if a shared library has no debugging information.
370 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
371 now complete on file names.
373 * When completing in expressions, gdb will attempt to limit
374 completions to allowable structure or union fields, where appropriate.
375 For instance, consider:
377 # struct example { int f1; double f2; };
378 # struct example variable;
381 If the user types TAB at the end of this command line, the available
382 completions will be "f1" and "f2".
384 * Inlined functions are now supported. They show up in backtraces, and
385 the "step", "next", and "finish" commands handle them automatically.
387 * GDB now supports the token-splicing (##) and stringification (#)
388 operators when expanding macros. It also supports variable-arity
391 * GDB now supports inspecting extra signal information, exported by
392 the new $_siginfo convenience variable. The feature is currently
393 implemented on linux ARM, i386 and amd64.
395 * GDB can now display the VFP floating point registers and NEON vector
396 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
397 can provide these registers (requires Linux 2.6.30 or later). Remote
398 and simulator targets may also provide them.
403 Search memory for a sequence of bytes.
406 Turn off `+'/`-' protocol acknowledgments to permit more efficient
407 operation over reliable transport links. Use of this packet is
408 controlled by the `set remote noack-packet' command.
411 Kill the process with the specified process ID. Use this in preference
412 to `k' when multiprocess protocol extensions are supported.
415 Obtains additional operating system information
419 Read or write additional signal information.
421 * Removed remote protocol undocumented extension
423 An undocumented extension to the remote protocol's `S' stop reply
424 packet that permited the stub to pass a process id was removed.
425 Remote servers should use the `T' stop reply packet instead.
427 * The "disassemble" command now supports an optional /m modifier to print mixed
430 * GDB now supports multiple function calling conventions according to the
431 DWARF-2 DW_AT_calling_convention function attribute.
433 * The SH target utilizes the aforementioned change to distinguish between gcc
434 and Renesas calling convention. It also adds the new CLI commands
435 `set/show sh calling-convention'.
437 * GDB can now read compressed debug sections, as produced by GNU gold
438 with the --compress-debug-sections=zlib flag.
440 * 64-bit core files are now supported on AIX.
442 * Thread switching is now supported on Tru64.
444 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
445 which will be allocated using malloc later in program execution.
447 * The qXfer:libraries:read remote procotol packet now allows passing a
448 list of section offsets.
450 * On GNU/Linux, GDB can now attach to stopped processes. Several race
451 conditions handling signals delivered during attach or thread creation
452 have also been fixed.
454 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
455 From the user's standpoint, all unqualified instances of True and False
456 are treated as the standard definitions, regardless of context.
458 * GDB now parses C++ symbol and type names more flexibly. For
461 template<typename T> class C { };
464 GDB will now correctly handle all of:
466 ptype C<char const *>
468 ptype C<const char *>
471 * New features in the GDB remote stub, gdbserver
473 - The "--wrapper" command-line argument tells gdbserver to use a
474 wrapper program to launch programs for debugging.
476 - On PowerPC and S/390 targets, it is now possible to use a single
477 gdbserver executable to debug both 32-bit and 64-bit programs.
478 (This requires gdbserver itself to be built as a 64-bit executable.)
480 - gdbserver uses the new noack protocol mode for TCP connections to
481 reduce communications latency, if also supported and enabled in GDB.
483 - Support for the sparc64-linux-gnu target is now included in
486 - The amd64-linux build of gdbserver now supports debugging both
487 32-bit and 64-bit programs.
489 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
490 now support hardware watchpoints, and will use them automatically
495 GDB now has support for scripting using Python. Whether this is
496 available is determined at configure time.
498 New GDB commands can now be written in Python.
500 * Ada tasking support
502 Ada tasks can now be inspected in GDB. The following commands have
506 Print the list of Ada tasks.
508 Print detailed information about task number N.
510 Print the task number of the current task.
512 Switch the context of debugging to task number N.
514 * Support for user-defined prefixed commands. The "define" command can
515 add new commands to existing prefixes, e.g. "target".
517 * Multi-inferior, multi-process debugging.
519 GDB now has generalized support for multi-inferior debugging. See
520 "Debugging Multiple Inferiors" in the manual for more information.
521 Although availability still depends on target support, the command
522 set is more uniform now. The GNU/Linux specific multi-forks support
523 has been migrated to this new framework. This implied some user
524 visible changes; see "New commands" and also "Removed commands"
527 * Target descriptions can now describe the target OS ABI. See the
528 "Target Description Format" section in the user manual for more
531 * Target descriptions can now describe "compatible" architectures
532 to indicate that the target can execute applications for a different
533 architecture in addition to those for the main target architecture.
534 See the "Target Description Format" section in the user manual for
537 * Multi-architecture debugging.
539 GDB now includes general supports for debugging applications on
540 hybrid systems that use more than one single processor architecture
541 at the same time. Each such hybrid architecture still requires
542 specific support to be added. The only hybrid architecture supported
543 in this version of GDB is the Cell Broadband Engine.
545 * GDB now supports integrated debugging of Cell/B.E. applications that
546 use both the PPU and SPU architectures. To enable support for hybrid
547 Cell/B.E. debugging, you need to configure GDB to support both the
548 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
549 --enable-targets configure option.
551 * Non-stop mode debugging.
553 For some targets, GDB now supports an optional mode of operation in
554 which you can examine stopped threads while other threads continue
555 to execute freely. This is referred to as non-stop mode, with the
556 old mode referred to as all-stop mode. See the "Non-Stop Mode"
557 section in the user manual for more information.
559 To be able to support remote non-stop debugging, a remote stub needs
560 to implement the non-stop mode remote protocol extensions, as
561 described in the "Remote Non-Stop" section of the user manual. The
562 GDB remote stub, gdbserver, has been adjusted to support these
563 extensions on linux targets.
565 * New commands (for set/show, see "New options" below)
567 catch syscall [NAME(S) | NUMBER(S)]
568 Catch system calls. Arguments, which should be names of system
569 calls or their numbers, mean catch only those syscalls. Without
570 arguments, every syscall will be caught. When the inferior issues
571 any of the specified syscalls, GDB will stop and announce the system
572 call, both when it is called and when its call returns. This
573 feature is currently available with a native GDB running on the
574 Linux Kernel, under the following architectures: x86, x86_64,
575 PowerPC and PowerPC64.
577 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
579 Search memory for a sequence of bytes.
581 maint set python print-stack
582 maint show python print-stack
583 Show a stack trace when an error is encountered in a Python script.
586 Invoke CODE by passing it to the Python interpreter.
591 These allow macros to be defined, undefined, and listed
595 Show operating system information about processes.
598 List the inferiors currently under GDB's control.
601 Switch focus to inferior number NUM.
604 Detach from inferior number NUM.
607 Kill inferior number NUM.
612 show spu stop-on-load
613 Control whether to stop for new SPE threads during Cell/B.E. debugging.
615 set spu auto-flush-cache
616 show spu auto-flush-cache
617 Control whether to automatically flush the software-managed cache
618 during Cell/B.E. debugging.
620 set sh calling-convention
621 show sh calling-convention
622 Control the calling convention used when calling SH target functions.
626 Control display of timestamps with GDB debugging output.
628 set disassemble-next-line
629 show disassemble-next-line
630 Control display of disassembled source lines or instructions when
633 set remote noack-packet
634 show remote noack-packet
635 Set/show the use of remote protocol QStartNoAckMode packet. See above
636 under "New remote packets."
638 set remote query-attached-packet
639 show remote query-attached-packet
640 Control use of remote protocol `qAttached' (query-attached) packet.
642 set remote read-siginfo-object
643 show remote read-siginfo-object
644 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
647 set remote write-siginfo-object
648 show remote write-siginfo-object
649 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
652 set remote reverse-continue
653 show remote reverse-continue
654 Control use of remote protocol 'bc' (reverse-continue) packet.
656 set remote reverse-step
657 show remote reverse-step
658 Control use of remote protocol 'bs' (reverse-step) packet.
660 set displaced-stepping
661 show displaced-stepping
662 Control displaced stepping mode. Displaced stepping is a way to
663 single-step over breakpoints without removing them from the debuggee.
664 Also known as "out-of-line single-stepping".
668 Control display of debugging info for displaced stepping.
670 maint set internal-error
671 maint show internal-error
672 Control what GDB does when an internal error is detected.
674 maint set internal-warning
675 maint show internal-warning
676 Control what GDB does when an internal warning is detected.
681 Use a wrapper program to launch programs for debugging.
683 set multiple-symbols (all|ask|cancel)
684 show multiple-symbols
685 The value of this variable can be changed to adjust the debugger behavior
686 when an expression or a breakpoint location contains an ambiguous symbol
687 name (an overloaded function name, for instance).
689 set breakpoint always-inserted
690 show breakpoint always-inserted
691 Keep breakpoints always inserted in the target, as opposed to inserting
692 them when resuming the target, and removing them when the target stops.
693 This option can improve debugger performance on slow remote targets.
695 set arm fallback-mode (arm|thumb|auto)
696 show arm fallback-mode
697 set arm force-mode (arm|thumb|auto)
699 These commands control how ARM GDB determines whether instructions
700 are ARM or Thumb. The default for both settings is auto, which uses
701 the current CPSR value for instructions without symbols; previous
702 versions of GDB behaved as if "set arm fallback-mode arm".
704 set disable-randomization
705 show disable-randomization
706 Standalone programs run with the virtual address space randomization enabled
707 by default on some platforms. This option keeps the addresses stable across
708 multiple debugging sessions.
712 Control whether other threads are stopped or not when some thread hits
717 Requests that asynchronous execution is enabled in the target, if available.
718 In this case, it's possible to resume target in the background, and interact
719 with GDB while the target is running. "show target-async" displays the
720 current state of asynchronous execution of the target.
722 set target-wide-charset
723 show target-wide-charset
724 The target-wide-charset is the name of the character set that GDB
725 uses when printing characters whose type is wchar_t.
727 set tcp auto-retry (on|off)
729 set tcp connect-timeout
730 show tcp connect-timeout
731 These commands allow GDB to retry failed TCP connections to a remote stub
732 with a specified timeout period; this is useful if the stub is launched
733 in parallel with GDB but may not be ready to accept connections immediately.
735 set libthread-db-search-path
736 show libthread-db-search-path
737 Control list of directories which GDB will search for appropriate
740 set schedule-multiple (on|off)
741 show schedule-multiple
742 Allow GDB to resume all threads of all processes or only threads of
747 Use more aggressive caching for accesses to the stack. This improves
748 performance of remote debugging (particularly backtraces) without
749 affecting correctness.
751 set interactive-mode (on|off|auto)
752 show interactive-mode
753 Control whether GDB runs in interactive mode (on) or not (off).
754 When in interactive mode, GDB waits for the user to answer all
755 queries. Otherwise, GDB does not wait and assumes the default
756 answer. When set to auto (the default), GDB determines which
757 mode to use based on the stdin settings.
762 For program forks, this is replaced by the new more generic `info
763 inferiors' command. To list checkpoints, you can still use the
764 `info checkpoints' command, which was an alias for the `info forks'
768 Replaced by the new `inferior' command. To switch between
769 checkpoints, you can still use the `restart' command, which was an
770 alias for the `fork' command.
773 This is removed, since some targets don't have a notion of
774 processes. To switch between processes, you can still use the
775 `inferior' command using GDB's own inferior number.
778 For program forks, this is replaced by the new more generic `kill
779 inferior' command. To delete a checkpoint, you can still use the
780 `delete checkpoint' command, which was an alias for the `delete
784 For program forks, this is replaced by the new more generic `detach
785 inferior' command. To detach a checkpoint, you can still use the
786 `detach checkpoint' command, which was an alias for the `detach
789 * New native configurations
791 x86/x86_64 Darwin i[34567]86-*-darwin*
793 x86_64 MinGW x86_64-*-mingw*
797 Lattice Mico32 lm32-*
798 x86 DICOS i[34567]86-*-dicos*
799 x86_64 DICOS x86_64-*-dicos*
802 * The GDB remote stub, gdbserver, now supports x86 Windows CE
803 (mingw32ce) debugging.
809 These commands were actually not implemented on any target.
811 *** Changes in GDB 6.8
813 * New native configurations
815 NetBSD/hppa hppa*-*netbsd*
816 Xtensa GNU/Linux xtensa*-*-linux*
820 NetBSD/hppa hppa*-*-netbsd*
821 Xtensa GNU/Lunux xtensa*-*-linux*
823 * Change in command line behavior -- corefiles vs. process ids.
825 When the '-p NUMBER' or '--pid NUMBER' options are used, and
826 attaching to process NUMBER fails, GDB no longer attempts to open a
827 core file named NUMBER. Attaching to a program using the -c option
828 is no longer supported. Instead, use the '-p' or '--pid' options.
830 * GDB can now be built as a native debugger for debugging Windows x86
831 (mingw32) Portable Executable (PE) programs.
833 * Pending breakpoints no longer change their number when their address
836 * GDB now supports breakpoints with multiple locations,
837 including breakpoints on C++ constructors, inside C++ templates,
838 and in inlined functions.
840 * GDB's ability to debug optimized code has been improved. GDB more
841 accurately identifies function bodies and lexical blocks that occupy
842 more than one contiguous range of addresses.
844 * Target descriptions can now describe registers for PowerPC.
846 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
847 registers on PowerPC targets.
849 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
850 targets even when the libthread_db library is not available.
852 * The GDB remote stub, gdbserver, now supports the new file transfer
853 commands (remote put, remote get, and remote delete).
855 * The GDB remote stub, gdbserver, now supports run and attach in
856 extended-remote mode.
858 * hppa*64*-*-hpux11* target broken
859 The debugger is unable to start a program and fails with the following
860 error: "Error trying to get information about dynamic linker".
861 The gdb-6.7 release is also affected.
863 * GDB now supports the --enable-targets= configure option to allow
864 building a single GDB executable that supports multiple remote
865 target architectures.
867 * GDB now supports debugging C and C++ programs which use the
868 Decimal Floating Point extension. In addition, the PowerPC target
869 now has a set of pseudo-registers to inspect decimal float values
870 stored in two consecutive float registers.
872 * The -break-insert MI command can optionally create pending
875 * Improved support for debugging Ada
876 Many improvements to the Ada language support have been made. These
878 - Better support for Ada2005 interface types
879 - Improved handling of arrays and slices in general
880 - Better support for Taft-amendment types
881 - The '{type} ADDRESS' expression is now allowed on the left hand-side
883 - Improved command completion in Ada
886 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
891 set print frame-arguments (all|scalars|none)
892 show print frame-arguments
893 The value of this variable can be changed to control which argument
894 values should be printed by the debugger when displaying a frame.
899 Transfer files to and from a remote target, and delete remote files.
906 Transfer files to and from a remote target, and delete remote files.
915 Open, close, read, write, and delete files on the remote system.
918 Attach to an existing process on the remote system, in extended-remote
922 Run a new process on the remote system, in extended-remote mode.
924 *** Changes in GDB 6.7
926 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
927 bfd, libiberty and opcodes, as revealed by static analysis donated by
928 Coverity, Inc. (http://scan.coverity.com).
930 * When looking up multiply-defined global symbols, GDB will now prefer the
931 symbol definition in the current shared library if it was built using the
932 -Bsymbolic linker option.
934 * When the Text User Interface (TUI) is not configured, GDB will now
935 recognize the -tui command-line option and print a message that the TUI
938 * The GDB remote stub, gdbserver, now has lower overhead for high
939 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
941 * GDB for MIPS targets now autodetects whether a remote target provides
942 32-bit or 64-bit register values.
944 * Support for C++ member pointers has been improved.
946 * GDB now understands XML target descriptions, which specify the
947 target's overall architecture. GDB can read a description from
948 a local file or over the remote serial protocol.
950 * Vectors of single-byte data use a new integer type which is not
951 automatically displayed as character or string data.
953 * The /s format now works with the print command. It displays
954 arrays of single-byte integers and pointers to single-byte integers
957 * Target descriptions can now describe target-specific registers,
958 for architectures which have implemented the support (currently
959 only ARM, M68K, and MIPS).
961 * GDB and the GDB remote stub, gdbserver, now support the XScale
964 * The GDB remote stub, gdbserver, has been updated to support
965 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
966 has been rewritten to use the standard GDB remote protocol.
968 * GDB can now step into C++ functions which are called through thunks.
970 * GDB for the Cell/B.E. SPU now supports overlay debugging.
972 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
973 layout. It also supports a TextSeg= and DataSeg= response when only
974 segment base addresses (rather than offsets) are available.
976 * The /i format now outputs any trailing branch delay slot instructions
977 immediately following the last instruction within the count specified.
979 * The GDB remote protocol "T" stop reply packet now supports a
980 "library" response. Combined with the new "qXfer:libraries:read"
981 packet, this response allows GDB to debug shared libraries on targets
982 where the operating system manages the list of loaded libraries (e.g.
983 Windows and SymbianOS).
985 * The GDB remote stub, gdbserver, now supports dynamic link libraries
986 (DLLs) on Windows and Windows CE targets.
988 * GDB now supports a faster verification that a .debug file matches its binary
989 according to its build-id signature, if the signature is present.
995 Enable or disable hardware flow control (RTS/CTS) on the serial port
996 when debugging using remote targets.
998 set mem inaccessible-by-default
999 show mem inaccessible-by-default
1000 If the target supplies a memory map, for instance via the remote
1001 protocol's "qXfer:memory-map:read" packet, setting this variable
1002 prevents GDB from accessing memory outside the memory map. This
1003 is useful for targets with memory mapped registers or which react
1004 badly to accesses of unmapped address space.
1006 set breakpoint auto-hw
1007 show breakpoint auto-hw
1008 If the target supplies a memory map, for instance via the remote
1009 protocol's "qXfer:memory-map:read" packet, setting this variable
1010 lets GDB use hardware breakpoints automatically for memory regions
1011 where it can not use software breakpoints. This covers both the
1012 "break" command and internal breakpoints used for other commands
1013 including "next" and "finish".
1016 catch exception unhandled
1017 Stop the program execution when Ada exceptions are raised.
1020 Stop the program execution when an Ada assertion failed.
1024 Set an alternate system root for target files. This is a more
1025 general version of "set solib-absolute-prefix", which is now
1026 an alias to "set sysroot".
1029 Provide extended SPU facility status information. This set of
1030 commands is available only when debugging the Cell/B.E. SPU
1033 * New native configurations
1035 OpenBSD/sh sh*-*openbsd*
1038 unset tdesc filename
1040 Use the specified local file as an XML target description, and do
1041 not query the target for its built-in description.
1045 OpenBSD/sh sh*-*-openbsd*
1046 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1047 Toshiba Media Processor mep-elf
1049 * New remote packets
1052 Ignore the specified signals; pass them directly to the debugged program
1053 without stopping other threads or reporting them to GDB.
1055 qXfer:features:read:
1056 Read an XML target description from the target, which describes its
1061 Read or write contents of an spufs file on the target system. These
1062 packets are available only on the Cell/B.E. SPU architecture.
1064 qXfer:libraries:read:
1065 Report the loaded shared libraries. Combined with new "T" packet
1066 response, this packet allows GDB to debug shared libraries on
1067 targets where the operating system manages the list of loaded
1068 libraries (e.g. Windows and SymbianOS).
1072 Support for these obsolete configurations has been removed.
1080 i[34567]86-*-lynxos*
1081 i[34567]86-*-netware*
1082 i[34567]86-*-sco3.2v5*
1083 i[34567]86-*-sco3.2v4*
1085 i[34567]86-*-sysv4.2*
1088 i[34567]86-*-unixware2*
1089 i[34567]86-*-unixware*
1098 * Other removed features
1105 Various m68k-only ROM monitors.
1112 Various Renesas ROM monitors and debugging interfaces for SH and
1117 Support for a Macraigor serial interface to on-chip debugging.
1118 GDB does not directly support the newer parallel or USB
1123 A debug information format. The predecessor to DWARF 2 and
1124 DWARF 3, which are still supported.
1126 Support for the HP aCC compiler on HP-UX/PA-RISC
1128 SOM-encapsulated symbolic debugging information, automatic
1129 invocation of pxdb, and the aCC custom C++ ABI. This does not
1130 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1131 with aCC can still be debugged on an assembly level.
1133 MIPS ".pdr" sections
1135 A MIPS-specific format used to describe stack frame layout
1136 in debugging information.
1140 GDB could work with an older version of Guile to debug
1141 the interpreter and Scheme programs running in it.
1143 set mips stack-arg-size
1144 set mips saved-gpreg-size
1146 Use "set mips abi" to control parameter passing for MIPS.
1148 *** Changes in GDB 6.6
1153 Cell Broadband Engine SPU spu-elf
1155 * GDB can now be configured as a cross-debugger targeting native Windows
1156 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1157 running on a Windows system over TCP/IP to debug Windows programs.
1159 * The GDB remote stub, gdbserver, has been updated to support Windows and
1160 Cygwin debugging. Both single-threaded and multi-threaded programs are
1163 * The "set trust-readonly-sections" command works again. This command was
1164 broken in GDB 6.3, 6.4, and 6.5.
1166 * The "load" command now supports writing to flash memory, if the remote
1167 stub provides the required support.
1169 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1170 longer requires symbolic debug information (e.g. DWARF-2).
1175 unset substitute-path
1176 show substitute-path
1177 Manage a list of substitution rules that GDB uses to rewrite the name
1178 of the directories where the sources are located. This can be useful
1179 for instance when the sources were moved to a different location
1180 between compilation and debugging.
1184 Print each CLI command as it is executed. Each command is prefixed with
1185 a number of `+' symbols representing the nesting depth.
1186 The source command now has a `-v' option to enable the same feature.
1190 The ARM Demon monitor support (RDP protocol, "target rdp").
1192 Kernel Object Display, an embedded debugging feature which only worked with
1193 an obsolete version of Cisco IOS.
1195 The 'set download-write-size' and 'show download-write-size' commands.
1197 * New remote packets
1200 Tell a stub about GDB client features, and request remote target features.
1201 The first feature implemented is PacketSize, which allows the target to
1202 specify the size of packets it can handle - to minimize the number of
1203 packets required and improve performance when connected to a remote
1207 Fetch an OS auxilliary vector from the remote stub. This packet is a
1208 more efficient replacement for qPart:auxv:read.
1210 qXfer:memory-map:read:
1211 Fetch a memory map from the remote stub, including information about
1212 RAM, ROM, and flash memory devices.
1217 Erase and program a flash memory device.
1219 * Removed remote packets
1222 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1223 used it, and only gdbserver implemented it.
1225 *** Changes in GDB 6.5
1229 Renesas M32C/M16C m32c-elf
1231 Morpho Technologies ms1 ms1-elf
1235 init-if-undefined Initialize a convenience variable, but
1236 only if it doesn't already have a value.
1238 The following commands are presently only implemented for native GNU/Linux:
1240 checkpoint Save a snapshot of the program state.
1242 restart <n> Return the program state to a
1243 previously saved state.
1245 info checkpoints List currently saved checkpoints.
1247 delete-checkpoint <n> Delete a previously saved checkpoint.
1249 set|show detach-on-fork Tell gdb whether to detach from a newly
1250 forked process, or to keep debugging it.
1252 info forks List forks of the user program that
1253 are available to be debugged.
1255 fork <n> Switch to debugging one of several
1256 forks of the user program that are
1257 available to be debugged.
1259 delete-fork <n> Delete a fork from the list of forks
1260 that are available to be debugged (and
1261 kill the forked process).
1263 detach-fork <n> Delete a fork from the list of forks
1264 that are available to be debugged (and
1265 allow the process to continue).
1269 Morpho Technologies ms2 ms1-elf
1271 * Improved Windows host support
1273 GDB now builds as a cross debugger hosted on i686-mingw32, including
1274 native console support, and remote communications using either
1275 network sockets or serial ports.
1277 * Improved Modula-2 language support
1279 GDB can now print most types in the Modula-2 syntax. This includes:
1280 basic types, set types, record types, enumerated types, range types,
1281 pointer types and ARRAY types. Procedure var parameters are correctly
1282 printed and hexadecimal addresses and character constants are also
1283 written in the Modula-2 syntax. Best results can be obtained by using
1284 GNU Modula-2 together with the -gdwarf-2 command line option.
1288 The ARM rdi-share module.
1290 The Netware NLM debug server.
1292 *** Changes in GDB 6.4
1294 * New native configurations
1296 OpenBSD/arm arm*-*-openbsd*
1297 OpenBSD/mips64 mips64-*-openbsd*
1301 Morpho Technologies ms1 ms1-elf
1303 * New command line options
1305 --batch-silent As for --batch, but totally silent.
1306 --return-child-result The debugger will exist with the same value
1307 the child (debugged) program exited with.
1308 --eval-command COMMAND, -ex COMMAND
1309 Execute a single GDB CLI command. This may be
1310 specified multiple times and in conjunction
1311 with the --command (-x) option.
1313 * Deprecated commands removed
1315 The following commands, that were deprecated in 2000, have been
1319 set|show arm disassembly-flavor set|show arm disassembler
1320 othernames set arm disassembler
1321 set|show remotedebug set|show debug remote
1322 set|show archdebug set|show debug arch
1323 set|show eventdebug set|show debug event
1326 * New BSD user-level threads support
1328 It is now possible to debug programs using the user-level threads
1329 library on OpenBSD and FreeBSD. Currently supported (target)
1332 FreeBSD/amd64 x86_64-*-freebsd*
1333 FreeBSD/i386 i386-*-freebsd*
1334 OpenBSD/i386 i386-*-openbsd*
1336 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1337 are not yet supported.
1339 * New support for Matsushita MN10300 w/sim added
1340 (Work in progress). mn10300-elf.
1342 * REMOVED configurations and files
1344 VxWorks and the XDR protocol *-*-vxworks
1345 Motorola MCORE mcore-*-*
1346 National Semiconductor NS32000 ns32k-*-*
1348 * New "set print array-indexes" command
1350 After turning this setting "on", GDB prints the index of each element
1351 when displaying arrays. The default is "off" to preserve the previous
1354 * VAX floating point support
1356 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1358 * User-defined command support
1360 In addition to using $arg0..$arg9 for argument passing, it is now possible
1361 to use $argc to determine now many arguments have been passed. See the
1362 section on user-defined commands in the user manual for more information.
1364 *** Changes in GDB 6.3:
1366 * New command line option
1368 GDB now accepts -l followed by a number to set the timeout for remote
1371 * GDB works with GCC -feliminate-dwarf2-dups
1373 GDB now supports a more compact representation of DWARF-2 debug
1374 information using DW_FORM_ref_addr references. These are produced
1375 by GCC with the option -feliminate-dwarf2-dups and also by some
1376 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1377 to use -feliminate-dwarf2-dups.
1379 * Internationalization
1381 When supported by the host system, GDB will be built with
1382 internationalization (libintl). The task of marking up the sources is
1383 continued, we're looking forward to our first translation.
1387 Initial support for debugging programs compiled with the GNAT
1388 implementation of the Ada programming language has been integrated
1389 into GDB. In this release, support is limited to expression evaluation.
1391 * New native configurations
1393 GNU/Linux/m32r m32r-*-linux-gnu
1397 GDB's remote protocol now includes support for the 'p' packet. This
1398 packet is used to fetch individual registers from a remote inferior.
1400 * END-OF-LIFE registers[] compatibility module
1402 GDB's internal register infrastructure has been completely rewritten.
1403 The new infrastructure making possible the implementation of key new
1404 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1407 GDB 6.3 will be the last release to include the the registers[]
1408 compatibility module that allowed out-of-date configurations to
1409 continue to work. This change directly impacts the following
1419 powerpc bdm protocol
1421 Unless there is activity to revive these configurations, they will be
1422 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1424 * OBSOLETE configurations and files
1426 Configurations that have been declared obsolete in this release have
1427 been commented out. Unless there is activity to revive these
1428 configurations, the next release of GDB will have their sources
1429 permanently REMOVED.
1438 *** Changes in GDB 6.2.1:
1440 * MIPS `break main; run' gave an heuristic-fence-post warning
1442 When attempting to run even a simple program, a warning about
1443 heuristic-fence-post being hit would be reported. This problem has
1446 * MIPS IRIX 'long double' crashed GDB
1448 When examining a long double variable, GDB would get a segmentation
1449 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1450 IRIX long double values).
1454 A bug in the VAX stack code was causing problems with the "next"
1455 command. This problem has been fixed.
1457 *** Changes in GDB 6.2:
1459 * Fix for ``many threads''
1461 On GNU/Linux systems that use the NPTL threads library, a program
1462 rapidly creating and deleting threads would confuse GDB leading to the
1465 ptrace: No such process.
1466 thread_db_get_info: cannot get thread info: generic error
1468 This problem has been fixed.
1470 * "-async" and "-noasync" options removed.
1472 Support for the broken "-noasync" option has been removed (it caused
1475 * New ``start'' command.
1477 This command runs the program until the begining of the main procedure.
1479 * New BSD Kernel Data Access Library (libkvm) interface
1481 Using ``target kvm'' it is now possible to debug kernel core dumps and
1482 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1483 platforms. Currently supported (native-only) configurations are:
1485 FreeBSD/amd64 x86_64-*-freebsd*
1486 FreeBSD/i386 i?86-*-freebsd*
1487 NetBSD/i386 i?86-*-netbsd*
1488 NetBSD/m68k m68*-*-netbsd*
1489 NetBSD/sparc sparc-*-netbsd*
1490 OpenBSD/amd64 x86_64-*-openbsd*
1491 OpenBSD/i386 i?86-*-openbsd*
1492 OpenBSD/m68k m68*-openbsd*
1493 OpenBSD/sparc sparc-*-openbsd*
1495 * Signal trampoline code overhauled
1497 Many generic problems with GDB's signal handling code have been fixed.
1498 These include: backtraces through non-contiguous stacks; recognition
1499 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1500 call; backtrace through a signal trampoline; step into and out of
1501 signal handlers; and single-stepping in the signal trampoline.
1503 Please note that kernel bugs are a limiting factor here. These
1504 features have been shown to work on an s390 GNU/Linux system that
1505 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1507 * Cygwin support for DWARF 2 added.
1509 * New native configurations
1511 GNU/Linux/hppa hppa*-*-linux*
1512 OpenBSD/hppa hppa*-*-openbsd*
1513 OpenBSD/m68k m68*-*-openbsd*
1514 OpenBSD/m88k m88*-*-openbsd*
1515 OpenBSD/powerpc powerpc-*-openbsd*
1516 NetBSD/vax vax-*-netbsd*
1517 OpenBSD/vax vax-*-openbsd*
1519 * END-OF-LIFE frame compatibility module
1521 GDB's internal frame infrastructure has been completely rewritten.
1522 The new infrastructure making it possible to support key new features
1523 including DWARF 2 Call Frame Information. To aid in the task of
1524 migrating old configurations to this new infrastructure, a
1525 compatibility module, that allowed old configurations to continue to
1526 work, was also included.
1528 GDB 6.2 will be the last release to include this frame compatibility
1529 module. This change directly impacts the following configurations:
1539 Unless there is activity to revive these configurations, they will be
1540 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1542 * REMOVED configurations and files
1544 Sun 3, running SunOS 3 m68*-*-sunos3*
1545 Sun 3, running SunOS 4 m68*-*-sunos4*
1546 Sun 2, running SunOS 3 m68000-*-sunos3*
1547 Sun 2, running SunOS 4 m68000-*-sunos4*
1548 Motorola 680x0 running LynxOS m68*-*-lynxos*
1549 AT&T 3b1/Unix pc m68*-att-*
1550 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1551 decstation mips-dec-* mips-little-*
1552 riscos mips-*-riscos* mips-*-sysv*
1553 sonymips mips-sony-*
1554 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1556 *** Changes in GDB 6.1.1:
1558 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1560 The TUI (Text-mode User Interface) is now built as part of a default
1561 GDB configuration. It is enabled by either selecting the TUI with the
1562 command line option "-i=tui" or by running the separate "gdbtui"
1563 program. For more information on the TUI, see the manual "Debugging
1566 * Pending breakpoint support (also included in GDB 6.1)
1568 Support has been added to allow you to specify breakpoints in shared
1569 libraries that have not yet been loaded. If a breakpoint location
1570 cannot be found, and the "breakpoint pending" option is set to auto,
1571 GDB queries you if you wish to make the breakpoint pending on a future
1572 shared-library load. If and when GDB resolves the breakpoint symbol,
1573 the pending breakpoint is removed as one or more regular breakpoints
1576 Pending breakpoints are very useful for GCJ Java debugging.
1578 * Fixed ISO-C build problems
1580 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1581 non ISO-C code that stopped them being built using a more strict ISO-C
1582 compiler (e.g., IBM's C compiler).
1584 * Fixed build problem on IRIX 5
1586 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1587 wasn't able to compile compile on an IRIX 5 system.
1589 * Added execute permission to gdb/gdbserver/configure
1591 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1592 permission. This bug would cause configure to fail on a number of
1593 systems (Solaris, IRIX). Ref: server/519.
1595 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1597 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1598 has been updated to use constant array sizes.
1600 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1602 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1603 its generated DWARF Call Frame Info. This encoding was causing GDB to
1604 panic, that panic has been fixed. Ref: gdb/1628.
1606 * Fixed a problem when examining parameters in shared library code.
1608 When examining parameters in optimized shared library code generated
1609 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1610 not available''. GDB now correctly displays the variable's value.
1612 *** Changes in GDB 6.1:
1614 * Removed --with-mmalloc
1616 Support for the mmalloc memory manager has been removed, as it
1617 conflicted with the internal gdb byte cache.
1619 * Changes in AMD64 configurations
1621 The AMD64 target now includes the %cs and %ss registers. As a result
1622 the AMD64 remote protocol has changed; this affects the floating-point
1623 and SSE registers. If you rely on those registers for your debugging,
1624 you should upgrade gdbserver on the remote side.
1626 * Revised SPARC target
1628 The SPARC target has been completely revised, incorporating the
1629 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1630 support for LynxOS and SunOS 4 has been dropped. Calling functions
1631 from within GDB on operating systems with a non-executable stack
1632 (Solaris, OpenBSD) now works.
1636 GDB has a new C++ demangler which does a better job on the mangled
1637 names generated by current versions of g++. It also runs faster, so
1638 with this and other changes gdb should now start faster on large C++
1641 * DWARF 2 Location Expressions
1643 GDB support for location expressions has been extended to support function
1644 arguments and frame bases. Older versions of GDB could crash when they
1647 * C++ nested types and namespaces
1649 GDB's support for nested types and namespaces in C++ has been
1650 improved, especially if you use the DWARF 2 debugging format. (This
1651 is the default for recent versions of GCC on most platforms.)
1652 Specifically, if you have a class "Inner" defined within a class or
1653 namespace "Outer", then GDB realizes that the class's name is
1654 "Outer::Inner", not simply "Inner". This should greatly reduce the
1655 frequency of complaints about not finding RTTI symbols. In addition,
1656 if you are stopped at inside of a function defined within a namespace,
1657 GDB modifies its name lookup accordingly.
1659 * New native configurations
1661 NetBSD/amd64 x86_64-*-netbsd*
1662 OpenBSD/amd64 x86_64-*-openbsd*
1663 OpenBSD/alpha alpha*-*-openbsd*
1664 OpenBSD/sparc sparc-*-openbsd*
1665 OpenBSD/sparc64 sparc64-*-openbsd*
1667 * New debugging protocols
1669 M32R with SDI protocol m32r-*-elf*
1671 * "set prompt-escape-char" command deleted.
1673 The command "set prompt-escape-char" has been deleted. This command,
1674 and its very obscure effet on GDB's prompt, was never documented,
1675 tested, nor mentioned in the NEWS file.
1677 * OBSOLETE configurations and files
1679 Configurations that have been declared obsolete in this release have
1680 been commented out. Unless there is activity to revive these
1681 configurations, the next release of GDB will have their sources
1682 permanently REMOVED.
1684 Sun 3, running SunOS 3 m68*-*-sunos3*
1685 Sun 3, running SunOS 4 m68*-*-sunos4*
1686 Sun 2, running SunOS 3 m68000-*-sunos3*
1687 Sun 2, running SunOS 4 m68000-*-sunos4*
1688 Motorola 680x0 running LynxOS m68*-*-lynxos*
1689 AT&T 3b1/Unix pc m68*-att-*
1690 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1691 decstation mips-dec-* mips-little-*
1692 riscos mips-*-riscos* mips-*-sysv*
1693 sonymips mips-sony-*
1694 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1696 * REMOVED configurations and files
1698 SGI Irix-4.x mips-sgi-irix4 or iris4
1699 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1700 Z8000 simulator z8k-zilog-none or z8ksim
1701 Matsushita MN10200 w/simulator mn10200-*-*
1702 H8/500 simulator h8500-hitachi-hms or h8500hms
1703 HP/PA running BSD hppa*-*-bsd*
1704 HP/PA running OSF/1 hppa*-*-osf*
1705 HP/PA Pro target hppa*-*-pro*
1706 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1707 386BSD i[3456]86-*-bsd*
1708 Sequent family i[3456]86-sequent-sysv4*
1709 i[3456]86-sequent-sysv*
1710 i[3456]86-sequent-bsd*
1711 SPARC running LynxOS sparc-*-lynxos*
1712 SPARC running SunOS 4 sparc-*-sunos4*
1713 Tsqware Sparclet sparclet-*-*
1714 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1716 *** Changes in GDB 6.0:
1720 Support for debugging the Objective-C programming language has been
1721 integrated into GDB.
1723 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1725 DWARF 2's Call Frame Information makes available compiler generated
1726 information that more exactly describes the program's run-time stack.
1727 By using this information, GDB is able to provide more robust stack
1730 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1731 have been updated to use a new backtrace mechanism which includes
1732 DWARF 2 CFI support.
1736 GDB's remote protocol has been extended to include support for hosted
1737 file I/O (where the remote target uses GDB's file system). See GDB's
1738 remote protocol documentation for details.
1740 * All targets using the new architecture framework.
1742 All of GDB's targets have been updated to use the new internal
1743 architecture framework. The way is now open for future GDB releases
1744 to include cross-architecture native debugging support (i386 on amd64,
1747 * GNU/Linux's Thread Local Storage (TLS)
1749 GDB now includes support for for the GNU/Linux implementation of
1750 per-thread variables.
1752 * GNU/Linux's Native POSIX Thread Library (NPTL)
1754 GDB's thread code has been updated to work with either the new
1755 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1757 * Separate debug info.
1759 GDB, in conjunction with BINUTILS, now supports a mechanism for
1760 automatically loading debug information from a separate file. Instead
1761 of shipping full debug and non-debug versions of system libraries,
1762 system integrators can now instead ship just the stripped libraries
1763 and optional debug files.
1765 * DWARF 2 Location Expressions
1767 DWARF 2 Location Expressions allow the compiler to more completely
1768 describe the location of variables (even in optimized code) to the
1771 GDB now includes preliminary support for location expressions (support
1772 for DW_OP_piece is still missing).
1776 A number of long standing bugs that caused GDB to die while starting a
1777 Java application have been fixed. GDB's Java support is now
1778 considered "useable".
1780 * GNU/Linux support for fork, vfork, and exec.
1782 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1783 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1786 * GDB supports logging output to a file
1788 There are two new commands, "set logging" and "show logging", which can be
1789 used to capture GDB's output to a file.
1791 * The meaning of "detach" has changed for gdbserver
1793 The "detach" command will now resume the application, as documented. To
1794 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1797 * d10v, m68hc11 `regs' command deprecated
1799 The `info registers' command has been updated so that it displays the
1800 registers using a format identical to the old `regs' command.
1804 A new command, "maint set profile on/off", has been added. This command can
1805 be used to enable or disable profiling while running GDB, to profile a
1806 session or a set of commands. In addition there is a new configure switch,
1807 "--enable-profiling", which will cause GDB to be compiled with profiling
1808 data, for more informative profiling results.
1810 * Default MI syntax changed to "mi2".
1812 The default MI (machine interface) syntax, enabled by the command line
1813 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1814 "mi1", can be enabled by specifying the option "-i=mi1".
1816 Support for the original "mi0" syntax (included in GDB 5.0) has been
1819 Fix for gdb/192: removed extraneous space when displaying frame level.
1820 Fix for gdb/672: update changelist is now output in mi list format.
1821 Fix for gdb/702: a -var-assign that updates the value now shows up
1822 in a subsequent -var-update.
1824 * New native configurations.
1826 FreeBSD/amd64 x86_64-*-freebsd*
1828 * Multi-arched targets.
1830 HP/PA HPUX11 hppa*-*-hpux*
1831 Renesas M32R/D w/simulator m32r-*-elf*
1833 * OBSOLETE configurations and files
1835 Configurations that have been declared obsolete in this release have
1836 been commented out. Unless there is activity to revive these
1837 configurations, the next release of GDB will have their sources
1838 permanently REMOVED.
1840 Z8000 simulator z8k-zilog-none or z8ksim
1841 Matsushita MN10200 w/simulator mn10200-*-*
1842 H8/500 simulator h8500-hitachi-hms or h8500hms
1843 HP/PA running BSD hppa*-*-bsd*
1844 HP/PA running OSF/1 hppa*-*-osf*
1845 HP/PA Pro target hppa*-*-pro*
1846 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1847 Sequent family i[3456]86-sequent-sysv4*
1848 i[3456]86-sequent-sysv*
1849 i[3456]86-sequent-bsd*
1850 Tsqware Sparclet sparclet-*-*
1851 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1853 * REMOVED configurations and files
1856 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1857 IBM AIX PS/2 i[3456]86-*-aix
1858 i386 running Mach 3.0 i[3456]86-*-mach3*
1859 i386 running Mach i[3456]86-*-mach*
1860 i386 running OSF/1 i[3456]86-*osf1mk*
1861 HP/Apollo 68k Family m68*-apollo*-sysv*,
1863 m68*-hp-bsd*, m68*-hp-hpux*
1864 Argonaut Risc Chip (ARC) arc-*-*
1865 Mitsubishi D30V d30v-*-*
1866 Fujitsu FR30 fr30-*-elf*
1867 OS/9000 i[34]86-*-os9k
1868 I960 with MON960 i960-*-coff
1870 * MIPS $fp behavior changed
1872 The convenience variable $fp, for the MIPS, now consistently returns
1873 the address of the current frame's base. Previously, depending on the
1874 context, $fp could refer to either $sp or the current frame's base
1875 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1876 The GNU Source-Level Debugger''.
1878 *** Changes in GDB 5.3:
1880 * GNU/Linux shared library multi-threaded performance improved.
1882 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1883 `/proc', in preference to `ptrace' for memory reads. This may result
1884 in an improvement in the start-up time of multi-threaded, shared
1885 library applications when run under GDB. One GDB user writes: ``loads
1886 shared libs like mad''.
1888 * ``gdbserver'' now supports multi-threaded applications on some targets
1890 Support for debugging multi-threaded applications which use
1891 the GNU/Linux LinuxThreads package has been added for
1892 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1893 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1895 * GDB now supports C/C++ preprocessor macros.
1897 GDB now expands preprocessor macro invocations in C/C++ expressions,
1898 and provides various commands for showing macro definitions and how
1901 The new command `macro expand EXPRESSION' expands any macro
1902 invocations in expression, and shows the result.
1904 The new command `show macro MACRO-NAME' shows the definition of the
1905 macro named MACRO-NAME, and where it was defined.
1907 Most compilers don't include information about macros in the debugging
1908 information by default. In GCC 3.1, for example, you need to compile
1909 your program with the options `-gdwarf-2 -g3'. If the macro
1910 information is present in the executable, GDB will read it.
1912 * Multi-arched targets.
1914 DEC Alpha (partial) alpha*-*-*
1915 DEC VAX (partial) vax-*-*
1917 National Semiconductor NS32000 (partial) ns32k-*-*
1918 Motorola 68000 (partial) m68k-*-*
1919 Motorola MCORE mcore-*-*
1923 Fujitsu FRV architecture added by Red Hat frv*-*-*
1926 * New native configurations
1928 Alpha NetBSD alpha*-*-netbsd*
1929 SH NetBSD sh*-*-netbsdelf*
1930 MIPS NetBSD mips*-*-netbsd*
1931 UltraSPARC NetBSD sparc64-*-netbsd*
1933 * OBSOLETE configurations and files
1935 Configurations that have been declared obsolete in this release have
1936 been commented out. Unless there is activity to revive these
1937 configurations, the next release of GDB will have their sources
1938 permanently REMOVED.
1940 Mitsubishi D30V d30v-*-*
1941 OS/9000 i[34]86-*-os9k
1942 IBM AIX PS/2 i[3456]86-*-aix
1943 Fujitsu FR30 fr30-*-elf*
1944 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1945 Argonaut Risc Chip (ARC) arc-*-*
1946 i386 running Mach 3.0 i[3456]86-*-mach3*
1947 i386 running Mach i[3456]86-*-mach*
1948 i386 running OSF/1 i[3456]86-*osf1mk*
1949 HP/Apollo 68k Family m68*-apollo*-sysv*,
1951 m68*-hp-bsd*, m68*-hp-hpux*
1952 I960 with MON960 i960-*-coff
1954 * OBSOLETE languages
1956 CHILL, a Pascal like language used by telecommunications companies.
1958 * REMOVED configurations and files
1960 AMD 29k family via UDI a29k-amd-udi, udi29k
1961 A29K VxWorks a29k-*-vxworks
1962 AMD 29000 embedded, using EBMON a29k-none-none
1963 AMD 29000 embedded with COFF a29k-none-coff
1964 AMD 29000 embedded with a.out a29k-none-aout
1966 testsuite/gdb.hp/gdb.threads-hp/ directory
1968 * New command "set max-user-call-depth <nnn>"
1970 This command allows the user to limit the call depth of user-defined
1971 commands. The default is 1024.
1973 * Changes in FreeBSD/i386 native debugging.
1975 Support for the "generate-core-file" has been added.
1977 * New commands "dump", "append", and "restore".
1979 These commands allow data to be copied from target memory
1980 to a bfd-format or binary file (dump and append), and back
1981 from a file into memory (restore).
1983 * Improved "next/step" support on multi-processor Alpha Tru64.
1985 The previous single-step mechanism could cause unpredictable problems,
1986 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1987 of a software single-step mechanism prevents this.
1989 *** Changes in GDB 5.2.1:
1997 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1998 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1999 Fix, by Joel Brobecker imported from mainline.
2001 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2002 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2003 Fix, by Fred Fish, imported from mainline.
2005 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2006 Surprisingly enough, it works now.
2007 By Michal Ludvig, imported from mainline.
2009 i386 hardware watchpoint support:
2010 avoid misses on second run for some targets.
2011 By Pierre Muller, imported from mainline.
2013 *** Changes in GDB 5.2:
2015 * New command "set trust-readonly-sections on[off]".
2017 This command is a hint that tells gdb that read-only sections
2018 really are read-only (ie. that their contents will not change).
2019 In this mode, gdb will go to the object file rather than the
2020 target to read memory from read-only sections (such as ".text").
2021 This can be a significant performance improvement on some
2022 (notably embedded) targets.
2024 * New command "generate-core-file" (or "gcore").
2026 This new gdb command allows the user to drop a core file of the child
2027 process state at any time. So far it's been implemented only for
2028 GNU/Linux and Solaris, but should be relatively easily ported to other
2029 hosts. Argument is core file name (defaults to core.<pid>).
2031 * New command line option
2033 GDB now accepts --pid or -p followed by a process id.
2035 * Change in command line behavior -- corefiles vs. process ids.
2037 There is a subtle behavior in the way in which GDB handles
2038 command line arguments. The first non-flag argument is always
2039 a program to debug, but the second non-flag argument may either
2040 be a corefile or a process id. Previously, GDB would attempt to
2041 open the second argument as a corefile, and if that failed, would
2042 issue a superfluous error message and then attempt to attach it as
2043 a process. Now, if the second argument begins with a non-digit,
2044 it will be treated as a corefile. If it begins with a digit,
2045 GDB will attempt to attach it as a process, and if no such process
2046 is found, will then attempt to open it as a corefile.
2048 * Changes in ARM configurations.
2050 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2051 configuration is fully multi-arch.
2053 * New native configurations
2055 ARM NetBSD arm*-*-netbsd*
2056 x86 OpenBSD i[3456]86-*-openbsd*
2057 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2058 Sparc64 running FreeBSD sparc64-*-freebsd*
2062 Sanyo XStormy16 xstormy16-elf
2064 * OBSOLETE configurations and files
2066 Configurations that have been declared obsolete in this release have
2067 been commented out. Unless there is activity to revive these
2068 configurations, the next release of GDB will have their sources
2069 permanently REMOVED.
2071 AMD 29k family via UDI a29k-amd-udi, udi29k
2072 A29K VxWorks a29k-*-vxworks
2073 AMD 29000 embedded, using EBMON a29k-none-none
2074 AMD 29000 embedded with COFF a29k-none-coff
2075 AMD 29000 embedded with a.out a29k-none-aout
2077 testsuite/gdb.hp/gdb.threads-hp/ directory
2079 * REMOVED configurations and files
2081 TI TMS320C80 tic80-*-*
2083 PowerPC Solaris powerpcle-*-solaris*
2084 PowerPC Windows NT powerpcle-*-cygwin32
2085 PowerPC Netware powerpc-*-netware*
2086 Harris/CXUX m88k m88*-harris-cxux*
2087 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2088 ns32k-utek-sysv* ns32k-utek-*
2089 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2090 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2091 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2092 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2093 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2095 * Changes to command line processing
2097 The new `--args' feature can be used to specify command-line arguments
2098 for the inferior from gdb's command line.
2100 * Changes to key bindings
2102 There is a new `operate-and-get-next' function bound to `C-o'.
2104 *** Changes in GDB 5.1.1
2106 Fix compile problem on DJGPP.
2108 Fix a problem with floating-point registers on the i386 being
2111 Fix to stop GDB crashing on .debug_str debug info.
2113 Numerous documentation fixes.
2115 Numerous testsuite fixes.
2117 *** Changes in GDB 5.1:
2119 * New native configurations
2121 Alpha FreeBSD alpha*-*-freebsd*
2122 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2123 MIPS GNU/Linux mips*-*-linux*
2124 MIPS SGI Irix 6.x mips*-sgi-irix6*
2125 ia64 AIX ia64-*-aix*
2126 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2130 Motorola 68HC11 and 68HC12 m68hc11-elf
2132 UltraSparc running GNU/Linux sparc64-*-linux*
2134 * OBSOLETE configurations and files
2136 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2137 Harris/CXUX m88k m88*-harris-cxux*
2138 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2139 ns32k-utek-sysv* ns32k-utek-*
2140 TI TMS320C80 tic80-*-*
2142 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2143 PowerPC Solaris powerpcle-*-solaris*
2144 PowerPC Windows NT powerpcle-*-cygwin32
2145 PowerPC Netware powerpc-*-netware*
2146 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2147 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2148 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2149 Apple Macintosh (MPW) host N/A
2151 stuff.c (Program to stuff files into a specially prepared space in kdb)
2152 kdb-start.c (Main loop for the standalone kernel debugger)
2154 Configurations that have been declared obsolete in this release have
2155 been commented out. Unless there is activity to revive these
2156 configurations, the next release of GDB will have their sources
2157 permanently REMOVED.
2159 * REMOVED configurations and files
2161 Altos 3068 m68*-altos-*
2162 Convex c1-*-*, c2-*-*
2164 ARM RISCix arm-*-* (as host)
2168 * GDB has been converted to ISO C.
2170 GDB's source code has been converted to ISO C. In particular, the
2171 sources are fully protoized, and rely on standard headers being
2176 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2178 * The MI enabled by default.
2180 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2181 revised and enabled by default. Packages which use GDB as a debugging
2182 engine behind a UI or another front end are encouraged to switch to
2183 using the GDB/MI interface, instead of the old annotations interface
2184 which is now deprecated.
2186 * Support for debugging Pascal programs.
2188 GDB now includes support for debugging Pascal programs. The following
2189 main features are supported:
2191 - Pascal-specific data types such as sets;
2193 - automatic recognition of Pascal sources based on file-name
2196 - Pascal-style display of data types, variables, and functions;
2198 - a Pascal expression parser.
2200 However, some important features are not yet supported.
2202 - Pascal string operations are not supported at all;
2204 - there are some problems with boolean types;
2206 - Pascal type hexadecimal constants are not supported
2207 because they conflict with the internal variables format;
2209 - support for Pascal objects and classes is not full yet;
2211 - unlike Pascal, GDB is case-sensitive for symbol names.
2213 * Changes in completion.
2215 Commands such as `shell', `run' and `set args', which pass arguments
2216 to inferior programs, now complete on file names, similar to what
2217 users expect at the shell prompt.
2219 Commands which accept locations, such as `disassemble', `print',
2220 `breakpoint', `until', etc. now complete on filenames as well as
2221 program symbols. Thus, if you type "break foob TAB", and the source
2222 files linked into the programs include `foobar.c', that file name will
2223 be one of the candidates for completion. However, file names are not
2224 considered for completion after you typed a colon that delimits a file
2225 name from a name of a function in that file, as in "break foo.c:bar".
2227 `set demangle-style' completes on available demangling styles.
2229 * New platform-independent commands:
2231 It is now possible to define a post-hook for a command as well as a
2232 hook that runs before the command. For more details, see the
2233 documentation of `hookpost' in the GDB manual.
2235 * Changes in GNU/Linux native debugging.
2237 Support for debugging multi-threaded programs has been completely
2238 revised for all platforms except m68k and sparc. You can now debug as
2239 many threads as your system allows you to have.
2241 Attach/detach is supported for multi-threaded programs.
2243 Support for SSE registers was added for x86. This doesn't work for
2244 multi-threaded programs though.
2246 * Changes in MIPS configurations.
2248 Multi-arch support is enabled for all MIPS configurations.
2250 GDB can now be built as native debugger on SGI Irix 6.x systems for
2251 debugging n32 executables. (Debugging 64-bit executables is not yet
2254 * Unified support for hardware watchpoints in all x86 configurations.
2256 Most (if not all) native x86 configurations support hardware-assisted
2257 breakpoints and watchpoints in a unified manner. This support
2258 implements debug register sharing between watchpoints, which allows to
2259 put a virtually infinite number of watchpoints on the same address,
2260 and also supports watching regions up to 16 bytes with several debug
2263 The new maintenance command `maintenance show-debug-regs' toggles
2264 debugging print-outs in functions that insert, remove, and test
2265 watchpoints and hardware breakpoints.
2267 * Changes in the DJGPP native configuration.
2269 New command ``info dos sysinfo'' displays assorted information about
2270 the CPU, OS, memory, and DPMI server.
2272 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2273 display information about segment descriptors stored in GDT, LDT, and
2276 New commands ``info dos pde'' and ``info dos pte'' display entries
2277 from Page Directory and Page Tables (for now works with CWSDPMI only).
2278 New command ``info dos address-pte'' displays the Page Table entry for
2279 a given linear address.
2281 GDB can now pass command lines longer than 126 characters to the
2282 program being debugged (requires an update to the libdbg.a library
2283 which is part of the DJGPP development kit).
2285 DWARF2 debug info is now supported.
2287 It is now possible to `step' and `next' through calls to `longjmp'.
2289 * Changes in documentation.
2291 All GDB documentation was converted to GFDL, the GNU Free
2292 Documentation License.
2294 Tracepoints-related commands are now fully documented in the GDB
2297 TUI, the Text-mode User Interface, is now documented in the manual.
2299 Tracepoints-related commands are now fully documented in the GDB
2302 The "GDB Internals" manual now has an index. It also includes
2303 documentation of `ui_out' functions, GDB coding standards, x86
2304 hardware watchpoints, and memory region attributes.
2306 * GDB's version number moved to ``version.in''
2308 The Makefile variable VERSION has been replaced by the file
2309 ``version.in''. People creating GDB distributions should update the
2310 contents of this file.
2314 GUD support is now a standard part of the EMACS distribution.
2316 *** Changes in GDB 5.0:
2318 * Improved support for debugging FP programs on x86 targets
2320 Unified and much-improved support for debugging floating-point
2321 programs on all x86 targets. In particular, ``info float'' now
2322 displays the FP registers in the same format on all x86 targets, with
2323 greater level of detail.
2325 * Improvements and bugfixes in hardware-assisted watchpoints
2327 It is now possible to watch array elements, struct members, and
2328 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2329 on x86 targets no longer erroneously trigger when the address is
2332 * Improvements in the native DJGPP version of GDB
2334 The distribution now includes all the scripts and auxiliary files
2335 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2336 machines ``out of the box''.
2338 The DJGPP version can now debug programs that use signals. It is
2339 possible to catch signals that happened in the debuggee, deliver
2340 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2341 would kill the program being debugged.) Programs that hook hardware
2342 interrupts (keyboard, timer, etc.) can also be debugged.
2344 It is now possible to debug DJGPP programs that redirect their
2345 standard handles or switch them to raw (as opposed to cooked) mode, or
2346 even close them. The command ``run < foo > bar'' works as expected,
2347 and ``info terminal'' reports useful information about the debuggee's
2348 terminal, including raw/cooked mode, redirection, etc.
2350 The DJGPP version now uses termios functions for console I/O, which
2351 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2354 DOS-style file names with drive letters are now fully supported by
2357 It is now possible to debug DJGPP programs that switch their working
2358 directory. It is also possible to rerun the debuggee any number of
2359 times without restarting GDB; thus, you can use the same setup,
2360 breakpoints, etc. for many debugging sessions.
2362 * New native configurations
2364 ARM GNU/Linux arm*-*-linux*
2365 PowerPC GNU/Linux powerpc-*-linux*
2369 Motorola MCore mcore-*-*
2370 x86 VxWorks i[3456]86-*-vxworks*
2371 PowerPC VxWorks powerpc-*-vxworks*
2372 TI TMS320C80 tic80-*-*
2374 * OBSOLETE configurations
2376 Altos 3068 m68*-altos-*
2377 Convex c1-*-*, c2-*-*
2379 ARM RISCix arm-*-* (as host)
2382 Configurations that have been declared obsolete will be commented out,
2383 but the code will be left in place. If there is no activity to revive
2384 these configurations before the next release of GDB, the sources will
2385 be permanently REMOVED.
2387 * Gould support removed
2389 Support for the Gould PowerNode and NP1 has been removed.
2391 * New features for SVR4
2393 On SVR4 native platforms (such as Solaris), if you attach to a process
2394 without first loading a symbol file, GDB will now attempt to locate and
2395 load symbols from the running process's executable file.
2397 * Many C++ enhancements
2399 C++ support has been greatly improved. Overload resolution now works properly
2400 in almost all cases. RTTI support is on the way.
2402 * Remote targets can connect to a sub-program
2404 A popen(3) style serial-device has been added. This device starts a
2405 sub-process (such as a stand-alone simulator) and then communicates
2406 with that. The sub-program to run is specified using the syntax
2407 ``|<program> <args>'' vis:
2409 (gdb) set remotedebug 1
2410 (gdb) target extended-remote |mn10300-elf-sim program-args
2412 * MIPS 64 remote protocol
2414 A long standing bug in the mips64 remote protocol where by GDB
2415 expected certain 32 bit registers (ex SR) to be transfered as 32
2416 instead of 64 bits has been fixed.
2418 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2419 added to provide backward compatibility with older versions of GDB.
2421 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2423 The command ``set remotebinarydownload'' command has been replaced by
2424 ``set remote X-packet''. Other commands in ``set remote'' family
2425 include ``set remote P-packet''.
2427 * Breakpoint commands accept ranges.
2429 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2430 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2431 ``tracepoint passcount'' also accepts a range of tracepoints.
2433 * ``apropos'' command added.
2435 The ``apropos'' command searches through command names and
2436 documentation strings, printing out matches, making it much easier to
2437 try to find a command that does what you are looking for.
2441 A new machine oriented interface (MI) has been added to GDB. This
2442 interface is designed for debug environments running GDB as a separate
2443 process. This is part of the long term libGDB project. See the
2444 "GDB/MI" chapter of the GDB manual for further information. It can be
2445 enabled by configuring with:
2447 .../configure --enable-gdbmi
2449 *** Changes in GDB-4.18:
2451 * New native configurations
2453 HP-UX 10.20 hppa*-*-hpux10.20
2454 HP-UX 11.x hppa*-*-hpux11.0*
2455 M68K GNU/Linux m68*-*-linux*
2459 Fujitsu FR30 fr30-*-elf*
2460 Intel StrongARM strongarm-*-*
2461 Mitsubishi D30V d30v-*-*
2463 * OBSOLETE configurations
2465 Gould PowerNode, NP1 np1-*-*, pn-*-*
2467 Configurations that have been declared obsolete will be commented out,
2468 but the code will be left in place. If there is no activity to revive
2469 these configurations before the next release of GDB, the sources will
2470 be permanently REMOVED.
2474 As a compatibility experiment, GDB's source files buildsym.h and
2475 buildsym.c have been converted to pure standard C, no longer
2476 containing any K&R compatibility code. We believe that all systems in
2477 use today either come with a standard C compiler, or have a GCC port
2478 available. If this is not true, please report the affected
2479 configuration to bug-gdb@gnu.org immediately. See the README file for
2480 information about getting a standard C compiler if you don't have one
2485 GDB now uses readline 2.2.
2487 * set extension-language
2489 You can now control the mapping between filename extensions and source
2490 languages by using the `set extension-language' command. For instance,
2491 you can ask GDB to treat .c files as C++ by saying
2492 set extension-language .c c++
2493 The command `info extensions' lists all of the recognized extensions
2494 and their associated languages.
2496 * Setting processor type for PowerPC and RS/6000
2498 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2499 you can use the `set processor' command to specify what variant of the
2500 PowerPC family you are debugging. The command
2504 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2505 following PowerPC and RS6000 variants:
2507 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2508 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2510 403GC IBM PowerPC 403GC
2511 505 Motorola PowerPC 505
2512 860 Motorola PowerPC 860 or 850
2513 601 Motorola PowerPC 601
2514 602 Motorola PowerPC 602
2515 603 Motorola/IBM PowerPC 603 or 603e
2516 604 Motorola PowerPC 604 or 604e
2517 750 Motorola/IBM PowerPC 750 or 750
2519 At the moment, this command just tells GDB what to name the
2520 special-purpose processor registers. Since almost all the affected
2521 registers are inaccessible to user-level programs, this command is
2522 only useful for remote debugging in its present form.
2526 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2527 more extensive support for HP-UX. Added features include shared
2528 library support, kernel threads and hardware watchpoints for 11.00,
2529 support for HP's ANSI C and C++ compilers, and a compatibility mode
2530 for xdb and dbx commands.
2534 HP's donation includes the new concept of catchpoints, which is a
2535 generalization of the old catch command. On HP-UX, it is now possible
2536 to catch exec, fork, and vfork, as well as library loading.
2538 This means that the existing catch command has changed; its first
2539 argument now specifies the type of catch to be set up. See the
2540 output of "help catch" for a list of catchpoint types.
2542 * Debugging across forks
2544 On HP-UX, you can choose which process to debug when a fork() happens
2549 HP has donated a curses-based terminal user interface (TUI). To get
2550 it, build with --enable-tui. Although this can be enabled for any
2551 configuration, at present it only works for native HP debugging.
2553 * GDB remote protocol additions
2555 A new protocol packet 'X' that writes binary data is now available.
2556 Default behavior is to try 'X', then drop back to 'M' if the stub
2557 fails to respond. The settable variable `remotebinarydownload'
2558 allows explicit control over the use of 'X'.
2560 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2561 full 64-bit address. The command
2563 set remoteaddresssize 32
2565 can be used to revert to the old behaviour. For existing remote stubs
2566 the change should not be noticed, as the additional address information
2569 In order to assist in debugging stubs, you may use the maintenance
2570 command `packet' to send any text string to the stub. For instance,
2572 maint packet heythere
2574 sends the packet "$heythere#<checksum>". Note that it is very easy to
2575 disrupt a debugging session by sending the wrong packet at the wrong
2578 The compare-sections command allows you to compare section data on the
2579 target to what is in the executable file without uploading or
2580 downloading, by comparing CRC checksums.
2582 * Tracing can collect general expressions
2584 You may now collect general expressions at tracepoints. This requires
2585 further additions to the target-side stub; see tracepoint.c and
2586 doc/agentexpr.texi for further details.
2588 * mask-address variable for Mips
2590 For Mips targets, you may control the zeroing of the upper 32 bits of
2591 a 64-bit address by entering `set mask-address on'. This is mainly
2592 of interest to users of embedded R4xxx and R5xxx processors.
2594 * Higher serial baud rates
2596 GDB's serial code now allows you to specify baud rates 57600, 115200,
2597 230400, and 460800 baud. (Note that your host system may not be able
2598 to achieve all of these rates.)
2602 The i960 configuration now includes an initial implementation of a
2603 builtin simulator, contributed by Jim Wilson.
2606 *** Changes in GDB-4.17:
2608 * New native configurations
2610 Alpha GNU/Linux alpha*-*-linux*
2611 Unixware 2.x i[3456]86-unixware2*
2612 Irix 6.x mips*-sgi-irix6*
2613 PowerPC GNU/Linux powerpc-*-linux*
2614 PowerPC Solaris powerpcle-*-solaris*
2615 Sparc GNU/Linux sparc-*-linux*
2616 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2620 Argonaut Risc Chip (ARC) arc-*-*
2621 Hitachi H8/300S h8300*-*-*
2622 Matsushita MN10200 w/simulator mn10200-*-*
2623 Matsushita MN10300 w/simulator mn10300-*-*
2624 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2625 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2626 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2627 Mitsubishi D10V w/simulator d10v-*-*
2628 Mitsubishi M32R/D w/simulator m32r-*-elf*
2629 Tsqware Sparclet sparclet-*-*
2630 NEC V850 w/simulator v850-*-*
2632 * New debugging protocols
2634 ARM with RDI protocol arm*-*-*
2635 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2636 DDB and LSI variants of PMON protocol mips*-*-*
2637 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2638 PowerPC with SDS protocol powerpc{,le}-*-eabi
2639 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2643 All configurations can now understand and use the DWARF 2 debugging
2644 format. The choice is automatic, if the symbol file contains DWARF 2
2649 GDB now includes basic Java language support. This support is
2650 only useful with Java compilers that produce native machine code.
2652 * solib-absolute-prefix and solib-search-path
2654 For SunOS and SVR4 shared libraries, you may now set the prefix for
2655 loading absolute shared library symbol files, and the search path for
2656 locating non-absolute shared library symbol files.
2658 * Live range splitting
2660 GDB can now effectively debug code for which GCC has performed live
2661 range splitting as part of its optimization. See gdb/doc/LRS for
2662 more details on the expected format of the stabs information.
2666 GDB's support for the GNU Hurd, including thread debugging, has been
2667 updated to work with current versions of the Hurd.
2671 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2672 instruction set. ARM GDB automatically detects when Thumb
2673 instructions are in use, and adjusts disassembly and backtracing
2678 GDB's MIPS target configurations now handle the MIP16 16-bit
2683 GDB now includes support for overlays; if an executable has been
2684 linked such that multiple sections are based at the same address, GDB
2685 will decide which section to use for symbolic info. You can choose to
2686 control the decision manually, using overlay commands, or implement
2687 additional target-side support and use "overlay load-target" to bring
2688 in the overlay mapping. Do "help overlay" for more detail.
2692 The command "info symbol <address>" displays information about
2693 the symbol at the specified address.
2697 The standard remote protocol now includes an extension that allows
2698 asynchronous collection and display of trace data. This requires
2699 extensive support in the target-side debugging stub. Tracing mode
2700 includes a new interaction mode in GDB and new commands: see the
2701 file tracepoint.c for more details.
2705 Configurations for embedded MIPS now include a simulator contributed
2706 by Cygnus Solutions. The simulator supports the instruction sets
2707 of most MIPS variants.
2711 Sparc configurations may now include the ERC32 simulator contributed
2712 by the European Space Agency. The simulator is not built into
2713 Sparc targets by default; configure with --enable-sim to include it.
2717 For target configurations that may include multiple variants of a
2718 basic architecture (such as MIPS and SH), you may now set the
2719 architecture explicitly. "set arch" sets, "info arch" lists
2720 the possible architectures.
2722 *** Changes in GDB-4.16:
2724 * New native configurations
2726 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2727 M68K NetBSD m68k-*-netbsd*
2728 PowerPC AIX 4.x powerpc-*-aix*
2729 PowerPC MacOS powerpc-*-macos*
2730 PowerPC Windows NT powerpcle-*-cygwin32
2731 RS/6000 AIX 4.x rs6000-*-aix4*
2735 ARM with RDP protocol arm-*-*
2736 I960 with MON960 i960-*-coff
2737 MIPS VxWorks mips*-*-vxworks*
2738 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2739 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2741 Matra Sparclet sparclet-*-*
2745 The powerpc-eabi configuration now includes the PSIM simulator,
2746 contributed by Andrew Cagney, with assistance from Mike Meissner.
2747 PSIM is a very elaborate model of the PowerPC, including not only
2748 basic instruction set execution, but also details of execution unit
2749 performance and I/O hardware. See sim/ppc/README for more details.
2753 GDB now works with Solaris 2.5.
2755 * Windows 95/NT native
2757 GDB will now work as a native debugger on Windows 95 and Windows NT.
2758 To build it from source, you must use the "gnu-win32" environment,
2759 which uses a DLL to emulate enough of Unix to run the GNU tools.
2760 Further information, binaries, and sources are available at
2761 ftp.cygnus.com, under pub/gnu-win32.
2763 * dont-repeat command
2765 If a user-defined command includes the command `dont-repeat', then the
2766 command will not be repeated if the user just types return. This is
2767 useful if the command is time-consuming to run, so that accidental
2768 extra keystrokes don't run the same command many times.
2770 * Send break instead of ^C
2772 The standard remote protocol now includes an option to send a break
2773 rather than a ^C to the target in order to interrupt it. By default,
2774 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2776 * Remote protocol timeout
2778 The standard remote protocol includes a new variable `remotetimeout'
2779 that allows you to set the number of seconds before GDB gives up trying
2780 to read from the target. The default value is 2.
2782 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2784 By default GDB will automatically keep track of objects as they are
2785 loaded and unloaded by the dynamic linker. By using the command `set
2786 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2787 when shared library events occur, thus allowing you to set breakpoints
2788 in shared libraries which are explicitly loaded by the inferior.
2790 Note this feature does not work on hpux8. On hpux9 you must link
2791 /usr/lib/end.o into your program. This feature should work
2792 automatically on hpux10.
2794 * Irix 5.x hardware watchpoint support
2796 Irix 5 configurations now support the use of hardware watchpoints.
2798 * Mips protocol "SYN garbage limit"
2800 When debugging a Mips target using the `target mips' protocol, you
2801 may set the number of characters that GDB will ignore by setting
2802 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2803 every character. The default value is 1050.
2805 * Recording and replaying remote debug sessions
2807 If you set `remotelogfile' to the name of a file, gdb will write to it
2808 a recording of a remote debug session. This recording may then be
2809 replayed back to gdb using "gdbreplay". See gdbserver/README for
2810 details. This is useful when you have a problem with GDB while doing
2811 remote debugging; you can make a recording of the session and send it
2812 to someone else, who can then recreate the problem.
2814 * Speedups for remote debugging
2816 GDB includes speedups for downloading and stepping MIPS systems using
2817 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2818 and more efficient S-record downloading.
2820 * Memory use reductions and statistics collection
2822 GDB now uses less memory and reports statistics about memory usage.
2823 Try the `maint print statistics' command, for example.
2825 *** Changes in GDB-4.15:
2827 * Psymtabs for XCOFF
2829 The symbol reader for AIX GDB now uses partial symbol tables. This
2830 can greatly improve startup time, especially for large executables.
2832 * Remote targets use caching
2834 Remote targets now use a data cache to speed up communication with the
2835 remote side. The data cache could lead to incorrect results because
2836 it doesn't know about volatile variables, thus making it impossible to
2837 debug targets which use memory mapped I/O devices. `set remotecache
2838 off' turns the the data cache off.
2840 * Remote targets may have threads
2842 The standard remote protocol now includes support for multiple threads
2843 in the target system, using new protocol commands 'H' and 'T'. See
2844 gdb/remote.c for details.
2848 If GDB is configured with `--enable-netrom', then it will include
2849 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2850 acts as though it is a bank of ROM on the target board, but you can
2851 write into it over the network. GDB's support consists only of
2852 support for fast loading into the emulated ROM; to debug, you must use
2853 another protocol, such as standard remote protocol. The usual
2854 sequence is something like
2856 target nrom <netrom-hostname>
2858 target remote <netrom-hostname>:1235
2862 GDB now includes support for the Apple Macintosh, as a host only. It
2863 may be run as either an MPW tool or as a standalone application, and
2864 it can debug through the serial port. All the usual GDB commands are
2865 available, but to the target command, you must supply "serial" as the
2866 device type instead of "/dev/ttyXX". See mpw-README in the main
2867 directory for more information on how to build. The MPW configuration
2868 scripts */mpw-config.in support only a few targets, and only the
2869 mips-idt-ecoff target has been tested.
2873 GDB configuration now uses autoconf. This is not user-visible,
2874 but does simplify configuration and building.
2878 GDB now supports hpux10.
2880 *** Changes in GDB-4.14:
2882 * New native configurations
2884 x86 FreeBSD i[345]86-*-freebsd
2885 x86 NetBSD i[345]86-*-netbsd
2886 NS32k NetBSD ns32k-*-netbsd
2887 Sparc NetBSD sparc-*-netbsd
2891 A29K VxWorks a29k-*-vxworks
2892 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2893 CPU32 EST-300 emulator m68*-*-est*
2894 PowerPC ELF powerpc-*-elf
2897 * Alpha OSF/1 support for procfs
2899 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2900 possible to attach to running processes. As the mounting of the /proc
2901 filesystem is optional on the Alpha, GDB automatically determines
2902 the availability of /proc during startup. This can lead to problems
2903 if /proc is unmounted after GDB has been started.
2905 * Arguments to user-defined commands
2907 User commands may accept up to 10 arguments separated by whitespace.
2908 Arguments are accessed within the user command via $arg0..$arg9. A
2911 print $arg0 + $arg1 + $arg2
2913 To execute the command use:
2916 Defines the command "adder" which prints the sum of its three arguments.
2917 Note the arguments are text substitutions, so they may reference variables,
2918 use complex expressions, or even perform inferior function calls.
2920 * New `if' and `while' commands
2922 This makes it possible to write more sophisticated user-defined
2923 commands. Both commands take a single argument, which is the
2924 expression to evaluate, and must be followed by the commands to
2925 execute, one per line, if the expression is nonzero, the list being
2926 terminated by the word `end'. The `if' command list may include an
2927 `else' word, which causes the following commands to be executed only
2928 if the expression is zero.
2930 * Fortran source language mode
2932 GDB now includes partial support for Fortran 77. It will recognize
2933 Fortran programs and can evaluate a subset of Fortran expressions, but
2934 variables and functions may not be handled correctly. GDB will work
2935 with G77, but does not yet know much about symbols emitted by other
2938 * Better HPUX support
2940 Most debugging facilities now work on dynamic executables for HPPAs
2941 running hpux9 or later. You can attach to running dynamically linked
2942 processes, but by default the dynamic libraries will be read-only, so
2943 for instance you won't be able to put breakpoints in them. To change
2944 that behavior do the following before running the program:
2950 This will cause the libraries to be mapped private and read-write.
2951 To revert to the normal behavior, do this:
2957 You cannot set breakpoints or examine data in the library until after
2958 the library is loaded if the function/data symbols do not have
2961 GDB can now also read debug symbols produced by the HP C compiler on
2962 HPPAs (sorry, no C++, Fortran or 68k support).
2964 * Target byte order now dynamically selectable
2966 You can choose which byte order to use with a target system, via the
2967 commands "set endian big" and "set endian little", and you can see the
2968 current setting by using "show endian". You can also give the command
2969 "set endian auto", in which case GDB will use the byte order
2970 associated with the executable. Currently, only embedded MIPS
2971 configurations support dynamic selection of target byte order.
2973 * New DOS host serial code
2975 This version uses DPMI interrupts to handle buffered I/O, so you
2976 no longer need to run asynctsr when debugging boards connected to
2979 *** Changes in GDB-4.13:
2981 * New "complete" command
2983 This lists all the possible completions for the rest of the line, if it
2984 were to be given as a command itself. This is intended for use by emacs.
2986 * Trailing space optional in prompt
2988 "set prompt" no longer adds a space for you after the prompt you set. This
2989 allows you to set a prompt which ends in a space or one that does not.
2991 * Breakpoint hit counts
2993 "info break" now displays a count of the number of times the breakpoint
2994 has been hit. This is especially useful in conjunction with "ignore"; you
2995 can ignore a large number of breakpoint hits, look at the breakpoint info
2996 to see how many times the breakpoint was hit, then run again, ignoring one
2997 less than that number, and this will get you quickly to the last hit of
3000 * Ability to stop printing at NULL character
3002 "set print null-stop" will cause GDB to stop printing the characters of
3003 an array when the first NULL is encountered. This is useful when large
3004 arrays actually contain only short strings.
3006 * Shared library breakpoints
3008 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3009 breakpoints in shared libraries before the executable is run.
3011 * Hardware watchpoints
3013 There is a new hardware breakpoint for the watch command for sparclite
3014 targets. See gdb/sparclite/hw_breakpoint.note.
3016 Hardware watchpoints are also now supported under GNU/Linux.
3020 Annotations have been added. These are for use with graphical interfaces,
3021 and are still experimental. Currently only gdba.el uses these.
3023 * Improved Irix 5 support
3025 GDB now works properly with Irix 5.2.
3027 * Improved HPPA support
3029 GDB now works properly with the latest GCC and GAS.
3031 * New native configurations
3033 Sequent PTX4 i[34]86-sequent-ptx4
3034 HPPA running OSF/1 hppa*-*-osf*
3035 Atari TT running SVR4 m68*-*-sysv4*
3036 RS/6000 LynxOS rs6000-*-lynxos*
3040 OS/9000 i[34]86-*-os9k
3041 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3044 * Hitachi SH7000 and E7000-PC ICE support
3046 There is now support for communicating with the Hitachi E7000-PC ICE.
3047 This is available automatically when GDB is configured for the SH.
3051 As usual, a variety of small fixes and improvements, both generic
3052 and configuration-specific. See the ChangeLog for more detail.
3054 *** Changes in GDB-4.12:
3056 * Irix 5 is now supported
3060 GDB-4.12 on the HPPA has a number of changes which make it unable
3061 to debug the output from the currently released versions of GCC and
3062 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3063 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3064 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3067 *** Changes in GDB-4.11:
3069 * User visible changes:
3073 The "set remotedebug" option is now consistent between the mips remote
3074 target, remote targets using the gdb-specific protocol, UDI (AMD's
3075 debug protocol for the 29k) and the 88k bug monitor. It is now an
3076 integer specifying a debug level (normally 0 or 1, but 2 means more
3077 debugging info for the mips target).
3079 * DEC Alpha native support
3081 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3082 debug info, but GDB works fairly well with the DEC compiler and should
3083 work with a future GCC release. See the README file for a few
3084 Alpha-specific notes.
3086 * Preliminary thread implementation
3088 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3090 * LynxOS native and target support for 386
3092 This release has been hosted on LynxOS 2.2, and also can be configured
3093 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3096 * Improvements in C++ mangling/demangling.
3098 This release has much better g++ debugging, specifically in name
3099 mangling/demangling, virtual function calls, print virtual table,
3100 call methods, ...etc.
3102 *** Changes in GDB-4.10:
3104 * User visible changes:
3106 Remote debugging using the GDB-specific (`target remote') protocol now
3107 supports the `load' command. This is only useful if you have some
3108 other way of getting the stub to the target system, and you can put it
3109 somewhere in memory where it won't get clobbered by the download.
3111 Filename completion now works.
3113 When run under emacs mode, the "info line" command now causes the
3114 arrow to point to the line specified. Also, "info line" prints
3115 addresses in symbolic form (as well as hex).
3117 All vxworks based targets now support a user settable option, called
3118 vxworks-timeout. This option represents the number of seconds gdb
3119 should wait for responses to rpc's. You might want to use this if
3120 your vxworks target is, perhaps, a slow software simulator or happens
3121 to be on the far side of a thin network line.
3125 This release contains support for using a DEC alpha as a GDB host for
3126 cross debugging. Native alpha debugging is not supported yet.
3129 *** Changes in GDB-4.9:
3133 This is the first GDB release which is accompanied by a matching testsuite.
3134 The testsuite requires installation of dejagnu, which should be available
3135 via ftp from most sites that carry GNU software.
3139 'Cfront' style demangling has had its name changed to 'ARM' style, to
3140 emphasize that it was written from the specifications in the C++ Annotated
3141 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3142 disclaimers, it still generated too much confusion with users attempting to
3143 use gdb with AT&T cfront.
3147 GDB now uses a standard remote interface to a simulator library.
3148 So far, the library contains simulators for the Zilog Z8001/2, the
3149 Hitachi H8/300, H8/500 and Super-H.
3151 * New targets supported
3153 H8/300 simulator h8300-hitachi-hms or h8300hms
3154 H8/500 simulator h8500-hitachi-hms or h8500hms
3155 SH simulator sh-hitachi-hms or sh
3156 Z8000 simulator z8k-zilog-none or z8ksim
3157 IDT MIPS board over serial line mips-idt-ecoff
3159 Cross-debugging to GO32 targets is supported. It requires a custom
3160 version of the i386-stub.c module which is integrated with the
3161 GO32 memory extender.
3163 * New remote protocols
3165 MIPS remote debugging protocol.
3167 * New source languages supported
3169 This version includes preliminary support for Chill, a Pascal like language
3170 used by telecommunications companies. Chill support is also being integrated
3171 into the GNU compiler, but we don't know when it will be publically available.
3174 *** Changes in GDB-4.8:
3176 * HP Precision Architecture supported
3178 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3179 version of this support was available as a set of patches from the
3180 University of Utah. GDB does not support debugging of programs
3181 compiled with the HP compiler, because HP will not document their file
3182 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3183 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3185 Many problems in the preliminary version have been fixed.
3187 * Faster and better demangling
3189 We have improved template demangling and fixed numerous bugs in the GNU style
3190 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3191 character types (wchar_t) are now supported. Demangling of each symbol is now
3192 only done once, and is cached when the symbol table for a file is read in.
3193 This results in a small increase in memory usage for C programs, a moderate
3194 increase in memory usage for C++ programs, and a fantastic speedup in
3197 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3198 from the specifications in the Annotated Reference Manual, which AT&T's
3199 compiler does not actually implement.
3201 * G++ multiple inheritance compiler problem
3203 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3204 inheritance lattices was reworked to properly discover ambiguities. We
3205 recently found an example which causes this new algorithm to fail in a
3206 very subtle way, producing bad debug information for those classes.
3207 The file 'gcc.patch' (in this directory) can be applied to gcc to
3208 circumvent the problem. A future GCC release will contain a complete
3211 The previous G++ debug info problem (mentioned below for the gdb-4.7
3212 release) is fixed in gcc version 2.3.2.
3214 * Improved configure script
3216 The `configure' script will now attempt to guess your system type if
3217 you don't supply a host system type. The old scheme of supplying a
3218 host system triplet is preferable over using this. All the magic is
3219 done in the new `config.guess' script. Examine it for details.
3221 We have also brought our configure script much more in line with the FSF's
3222 version. It now supports the --with-xxx options. In particular,
3223 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3224 The resulting GDB will not be able to read arbitrary object file formats --
3225 only the format ``expected'' to be used on the configured target system.
3226 We hope to make this the default in a future release.
3228 * Documentation improvements
3230 There's new internal documentation on how to modify GDB, and how to
3231 produce clean changes to the code. We implore people to read it
3232 before submitting changes.
3234 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3235 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3236 `info' files are also provided. To build `info' files from scratch,
3237 you will need the latest `makeinfo' release, which will be available in
3238 a future texinfo-X.Y release.
3240 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3241 We're not sure exactly which versions have this problem, but it has
3242 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3243 or better. If that isn't possible, there is a patch in
3244 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3245 around this problem.
3249 GDB now supports array constants that can be used in expressions typed in by
3250 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3251 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3254 The new directory `gdb/sparclite' contains a program that demonstrates
3255 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3257 * New native hosts supported
3259 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3260 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3262 * New targets supported
3264 AMD 29k family via UDI a29k-amd-udi or udi29k
3266 * New file formats supported
3268 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3269 HPUX core files, and SCO 3.2v2 core files.
3273 Attaching to processes now works again; thanks for the many bug reports.
3275 We have also stomped on a bunch of core dumps caused by
3276 printf_filtered("%s") problems.
3278 We eliminated a copyright problem on the rpc and ptrace header files
3279 for VxWorks, which was discovered at the last minute during the 4.7
3280 release. You should now be able to build a VxWorks GDB.
3282 You can now interrupt gdb while an attached process is running. This
3283 will cause the attached process to stop, and give control back to GDB.
3285 We fixed problems caused by using too many file descriptors
3286 for reading symbols from object files and libraries. This was
3287 especially a problem for programs that used many (~100) shared
3290 The `step' command now only enters a subroutine if there is line number
3291 information for the subroutine. Otherwise it acts like the `next'
3292 command. Previously, `step' would enter subroutines if there was
3293 any debugging information about the routine. This avoids problems
3294 when using `cc -g1' on MIPS machines.
3296 * Internal improvements
3298 GDB's internal interfaces have been improved to make it easier to support
3299 debugging of multiple languages in the future.
3301 GDB now uses a common structure for symbol information internally.
3302 Minimal symbols (derived from linkage symbols in object files), partial
3303 symbols (from a quick scan of debug information), and full symbols
3304 contain a common subset of information, making it easier to write
3305 shared code that handles any of them.
3307 * New command line options
3309 We now accept --silent as an alias for --quiet.
3313 The memory-mapped-malloc library is now licensed under the GNU Library
3314 General Public License.
3316 *** Changes in GDB-4.7:
3318 * Host/native/target split
3320 GDB has had some major internal surgery to untangle the support for
3321 hosts and remote targets. Now, when you configure GDB for a remote
3322 target, it will no longer load in all of the support for debugging
3323 local programs on the host. When fully completed and tested, this will
3324 ensure that arbitrary host/target combinations are possible.
3326 The primary conceptual shift is to separate the non-portable code in
3327 GDB into three categories. Host specific code is required any time GDB
3328 is compiled on that host, regardless of the target. Target specific
3329 code relates to the peculiarities of the target, but can be compiled on
3330 any host. Native specific code is everything else: it can only be
3331 built when the host and target are the same system. Child process
3332 handling and core file support are two common `native' examples.
3334 GDB's use of /proc for controlling Unix child processes is now cleaner.
3335 It has been split out into a single module under the `target_ops' vector,
3336 plus two native-dependent functions for each system that uses /proc.
3338 * New hosts supported
3340 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3341 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3342 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3344 * New targets supported
3346 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3347 68030 and CPU32 m68030-*-*, m68332-*-*
3349 * New native hosts supported
3351 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3352 (386bsd is not well tested yet)
3353 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3355 * New file formats supported
3357 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3358 supports reading of `a.out.adobe' object files, which are an a.out
3359 format extended with minimal information about multiple sections.
3363 `show copying' is the same as the old `info copying'.
3364 `show warranty' is the same as `info warrantee'.
3365 These were renamed for consistency. The old commands continue to work.
3367 `info handle' is a new alias for `info signals'.
3369 You can now define pre-command hooks, which attach arbitrary command
3370 scripts to any command. The commands in the hook will be executed
3371 prior to the user's command. You can also create a hook which will be
3372 executed whenever the program stops. See gdb.texinfo.
3376 We now deal with Cfront style name mangling, and can even extract type
3377 info from mangled symbols. GDB can automatically figure out which
3378 symbol mangling style your C++ compiler uses.
3380 Calling of methods and virtual functions has been improved as well.
3384 The crash that occured when debugging Sun Ansi-C compiled binaries is
3385 fixed. This was due to mishandling of the extra N_SO stabs output
3388 We also finally got Ultrix 4.2 running in house, and fixed core file
3389 support, with help from a dozen people on the net.
3391 John M. Farrell discovered that the reason that single-stepping was so
3392 slow on all of the Mips based platforms (primarily SGI and DEC) was
3393 that we were trying to demangle and lookup a symbol used for internal
3394 purposes on every instruction that was being stepped through. Changing
3395 the name of that symbol so that it couldn't be mistaken for a C++
3396 mangled symbol sped things up a great deal.
3398 Rich Pixley sped up symbol lookups in general by getting much smarter
3399 about when C++ symbol mangling is necessary. This should make symbol
3400 completion (TAB on the command line) much faster. It's not as fast as
3401 we'd like, but it's significantly faster than gdb-4.6.
3405 A new user controllable variable 'call_scratch_address' can
3406 specify the location of a scratch area to be used when GDB
3407 calls a function in the target. This is necessary because the
3408 usual method of putting the scratch area on the stack does not work
3409 in systems that have separate instruction and data spaces.
3411 We integrated changes to support the 29k UDI (Universal Debugger
3412 Interface), but discovered at the last minute that we didn't have all
3413 of the appropriate copyright paperwork. We are working with AMD to
3414 resolve this, and hope to have it available soon.
3418 We have sped up the remote serial line protocol, especially for targets
3419 with lots of registers. It now supports a new `expedited status' ('T')
3420 message which can be used in place of the existing 'S' status message.
3421 This allows the remote stub to send only the registers that GDB
3422 needs to make a quick decision about single-stepping or conditional
3423 breakpoints, eliminating the need to fetch the entire register set for
3424 each instruction being stepped through.
3426 The GDB remote serial protocol now implements a write-through cache for
3427 registers, only re-reading the registers if the target has run.
3429 There is also a new remote serial stub for SPARC processors. You can
3430 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3431 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3432 processor with a serial port.
3436 Configure.in files have become much easier to read and modify. A new
3437 `table driven' format makes it more obvious what configurations are
3438 supported, and what files each one uses.
3442 There is a new opcodes library which will eventually contain all of the
3443 disassembly routines and opcode tables. At present, it only contains
3444 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3445 disassembler (binutils/objdump) to share these routines.
3447 The libiberty library is now copylefted under the GNU Library General
3448 Public License. This allows more liberal use, and was done so libg++
3449 can use it. This makes no difference to GDB, since the Library License
3450 grants all the rights from the General Public License.
3454 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3455 reference to the stabs symbol info used by the debugger. It is (as far
3456 as we know) the only published document on this fascinating topic. We
3457 encourage you to read it, compare it to the stabs information on your
3458 system, and send improvements on the document in general (to
3459 bug-gdb@prep.ai.mit.edu).
3461 And, of course, many bugs have been fixed.
3464 *** Changes in GDB-4.6:
3466 * Better support for C++ function names
3468 GDB now accepts as input the "demangled form" of C++ overloaded function
3469 names and member function names, and can do command completion on such names
3470 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3471 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3472 Make use of command completion, it is your friend.
3474 GDB also now accepts a variety of C++ mangled symbol formats. They are
3475 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3476 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3477 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3478 for the list of formats.
3480 * G++ symbol mangling problem
3482 Recent versions of gcc have a bug in how they emit debugging information for
3483 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3484 directory) can be applied to gcc to fix the problem. Alternatively, if you
3485 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3486 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3487 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3490 * New 'maintenance' command
3492 All of the commands related to hacking GDB internals have been moved out of
3493 the main command set, and now live behind the 'maintenance' command. This
3494 can also be abbreviated as 'mt'. The following changes were made:
3496 dump-me -> maintenance dump-me
3497 info all-breakpoints -> maintenance info breakpoints
3498 printmsyms -> maintenance print msyms
3499 printobjfiles -> maintenance print objfiles
3500 printpsyms -> maintenance print psymbols
3501 printsyms -> maintenance print symbols
3503 The following commands are new:
3505 maintenance demangle Call internal GDB demangler routine to
3506 demangle a C++ link name and prints the result.
3507 maintenance print type Print a type chain for a given symbol
3509 * Change to .gdbinit file processing
3511 We now read the $HOME/.gdbinit file before processing the argv arguments
3512 (e.g. reading symbol files or core files). This allows global parameters to
3513 be set, which will apply during the symbol reading. The ./.gdbinit is still
3514 read after argv processing.
3516 * New hosts supported
3518 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3520 GNU/Linux support i386-unknown-linux or linux
3522 We are also including code to support the HP/PA running BSD and HPUX. This
3523 is almost guaranteed not to work, as we didn't have time to test or build it
3524 for this release. We are including it so that the more adventurous (or
3525 masochistic) of you can play with it. We also had major problems with the
3526 fact that the compiler that we got from HP doesn't support the -g option.
3529 * New targets supported
3531 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3533 * More smarts about finding #include files
3535 GDB now remembers the compilation directory for all include files, and for
3536 all files from which C is generated (like yacc and lex sources). This
3537 greatly improves GDB's ability to find yacc/lex sources, and include files,
3538 especially if you are debugging your program from a directory different from
3539 the one that contains your sources.
3541 We also fixed a bug which caused difficulty with listing and setting
3542 breakpoints in include files which contain C code. (In the past, you had to
3543 try twice in order to list an include file that you hadn't looked at before.)
3545 * Interesting infernals change
3547 GDB now deals with arbitrary numbers of sections, where the symbols for each
3548 section must be relocated relative to that section's landing place in the
3549 target's address space. This work was needed to support ELF with embedded
3550 stabs used by Solaris-2.0.
3552 * Bug fixes (of course!)
3554 There have been loads of fixes for the following things:
3555 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3556 i960, stabs, DOS(GO32), procfs, etc...
3558 See the ChangeLog for details.
3560 *** Changes in GDB-4.5:
3562 * New machines supported (host and target)
3564 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3566 SGI Irix-4.x mips-sgi-irix4 or iris4
3568 * New malloc package
3570 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3571 Mmalloc is capable of handling mutiple heaps of memory. It is also
3572 capable of saving a heap to a file, and then mapping it back in later.
3573 This can be used to greatly speedup the startup of GDB by using a
3574 pre-parsed symbol table which lives in a mmalloc managed heap. For
3575 more details, please read mmalloc/mmalloc.texi.
3579 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3580 'help info proc' for details.
3582 * MIPS ecoff symbol table format
3584 The code that reads MIPS symbol table format is now supported on all hosts.
3585 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3588 * File name changes for MS-DOS
3590 Many files in the config directories have been renamed to make it easier to
3591 support GDB on MS-DOSe systems (which have very restrictive file name
3592 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3593 environment) is close to working but has some remaining problems. Note
3594 that debugging of DOS programs is not supported, due to limitations
3595 in the ``operating system'', but it can be used to host cross-debugging.
3597 * Cross byte order fixes
3599 Many fixes have been made to support cross debugging of Sparc and MIPS
3600 targets from hosts whose byte order differs.
3602 * New -mapped and -readnow options
3604 If memory-mapped files are available on your system through the 'mmap'
3605 system call, you can use the -mapped option on the `file' or
3606 `symbol-file' commands to cause GDB to write the symbols from your
3607 program into a reusable file. If the program you are debugging is
3608 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3609 Future GDB debugging sessions will notice the presence of this file,
3610 and will quickly map in symbol information from it, rather than reading
3611 the symbol table from the executable program. Using the '-mapped'
3612 option in a GDB `file' or `symbol-file' command has the same effect as
3613 starting GDB with the '-mapped' command-line option.
3615 You can cause GDB to read the entire symbol table immediately by using
3616 the '-readnow' option with any of the commands that load symbol table
3617 information (or on the GDB command line). This makes the command
3618 slower, but makes future operations faster.
3620 The -mapped and -readnow options are typically combined in order to
3621 build a `fred.syms' file that contains complete symbol information.
3622 A simple GDB invocation to do nothing but build a `.syms' file for future
3625 gdb -batch -nx -mapped -readnow programname
3627 The `.syms' file is specific to the host machine on which GDB is run.
3628 It holds an exact image of GDB's internal symbol table. It cannot be
3629 shared across multiple host platforms.
3631 * longjmp() handling
3633 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3634 siglongjmp() without losing control. This feature has not yet been ported to
3635 all systems. It currently works on many 386 platforms, all MIPS-based
3636 platforms (SGI, DECstation, etc), and Sun3/4.
3640 Preliminary work has been put in to support the new Solaris OS from Sun. At
3641 this time, it can control and debug processes, but it is not capable of
3646 As always, many many bug fixes. The major areas were with g++, and mipsread.
3647 People using the MIPS-based platforms should experience fewer mysterious
3648 crashes and trashed symbol tables.
3650 *** Changes in GDB-4.4:
3652 * New machines supported (host and target)
3654 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3656 BSD Reno on Vax vax-dec-bsd
3657 Ultrix on Vax vax-dec-ultrix
3659 * New machines supported (target)
3661 AMD 29000 embedded, using EBMON a29k-none-none
3665 GDB continues to improve its handling of C++. `References' work better.
3666 The demangler has also been improved, and now deals with symbols mangled as
3667 per the Annotated C++ Reference Guide.
3669 GDB also now handles `stabs' symbol information embedded in MIPS
3670 `ecoff' symbol tables. Since the ecoff format was not easily
3671 extensible to handle new languages such as C++, this appeared to be a
3672 good way to put C++ debugging info into MIPS binaries. This option
3673 will be supported in the GNU C compiler, version 2, when it is
3676 * New features for SVR4
3678 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3679 shared libraries. Debugging dynamically linked programs should present
3680 only minor differences from debugging statically linked programs.
3682 The `info proc' command will print out information about any process
3683 on an SVR4 system (including the one you are debugging). At the moment,
3684 it prints the address mappings of the process.
3686 If you bring up GDB on another SVR4 system, please send mail to
3687 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3689 * Better dynamic linking support in SunOS
3691 Reading symbols from shared libraries which contain debugging symbols
3692 now works properly. However, there remain issues such as automatic
3693 skipping of `transfer vector' code during function calls, which
3694 make it harder to debug code in a shared library, than to debug the
3695 same code linked statically.
3699 GDB is now using the latest `getopt' routines from the FSF. This
3700 version accepts the -- prefix for options with long names. GDB will
3701 continue to accept the old forms (-option and +option) as well.
3702 Various single letter abbreviations for options have been explicity
3703 added to the option table so that they won't get overshadowed in the
3704 future by other options that begin with the same letter.
3708 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3709 Many assorted bugs have been handled. Many more remain to be handled.
3710 See the various ChangeLog files (primarily in gdb and bfd) for details.
3713 *** Changes in GDB-4.3:
3715 * New machines supported (host and target)
3717 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3718 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3719 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3721 * Almost SCO Unix support
3723 We had hoped to support:
3724 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3725 (except for core file support), but we discovered very late in the release
3726 that it has problems with process groups that render gdb unusable. Sorry
3727 about that. I encourage people to fix it and post the fixes.
3729 * Preliminary ELF and DWARF support
3731 GDB can read ELF object files on System V Release 4, and can handle
3732 debugging records for C, in DWARF format, in ELF files. This support
3733 is preliminary. If you bring up GDB on another SVR4 system, please
3734 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3739 GDB now uses the latest `readline' library. One user-visible change
3740 is that two tabs will list possible command completions, which previously
3741 required typing M-? (meta-question mark, or ESC ?).
3745 The `stepi' bug that many of you noticed has been squashed.
3746 Many bugs in C++ have been handled. Many more remain to be handled.
3747 See the various ChangeLog files (primarily in gdb and bfd) for details.
3749 * State of the MIPS world (in case you wondered):
3751 GDB can understand the symbol tables emitted by the compilers
3752 supplied by most vendors of MIPS-based machines, including DEC. These
3753 symbol tables are in a format that essentially nobody else uses.
3755 Some versions of gcc come with an assembler post-processor called
3756 mips-tfile. This program is required if you want to do source-level
3757 debugging of gcc-compiled programs. I believe FSF does not ship
3758 mips-tfile with gcc version 1, but it will eventually come with gcc
3761 Debugging of g++ output remains a problem. g++ version 1.xx does not
3762 really support it at all. (If you're lucky, you should be able to get
3763 line numbers and stack traces to work, but no parameters or local
3764 variables.) With some work it should be possible to improve the
3767 When gcc version 2 is released, you will have somewhat better luck.
3768 However, even then you will get confusing results for inheritance and
3771 We will eventually provide full debugging of g++ output on
3772 DECstations. This will probably involve some kind of stabs-in-ecoff
3773 encapulation, but the details have not been worked out yet.
3776 *** Changes in GDB-4.2:
3778 * Improved configuration
3780 Only one copy of `configure' exists now, and it is not self-modifying.
3781 Porting BFD is simpler.
3785 The `step' and `next' commands now only stop at the first instruction
3786 of a source line. This prevents the multiple stops that used to occur
3787 in switch statements, for-loops, etc. `Step' continues to stop if a
3788 function that has debugging information is called within the line.
3792 Lots of small bugs fixed. More remain.
3794 * New host supported (not target)
3796 Intel 386 PC clone running Mach i386-none-mach
3799 *** Changes in GDB-4.1:
3801 * Multiple source language support
3803 GDB now has internal scaffolding to handle several source languages.
3804 It determines the type of each source file from its filename extension,
3805 and will switch expression parsing and number formatting to match the
3806 language of the function in the currently selected stack frame.
3807 You can also specifically set the language to be used, with
3808 `set language c' or `set language modula-2'.
3812 GDB now has preliminary support for the GNU Modula-2 compiler,
3813 currently under development at the State University of New York at
3814 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3815 continue through the fall of 1991 and into 1992.
3817 Other Modula-2 compilers are currently not supported, and attempting to
3818 debug programs compiled with them will likely result in an error as the
3819 symbol table is read. Feel free to work on it, though!
3821 There are hooks in GDB for strict type checking and range checking,
3822 in the `Modula-2 philosophy', but they do not currently work.
3826 GDB can now write to executable and core files (e.g. patch
3827 a variable's value). You must turn this switch on, specify
3828 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3829 by assigning a new value to a variable. Modifications take
3832 * Automatic SunOS shared library reading
3834 When you run your program, GDB automatically determines where its
3835 shared libraries (if any) have been loaded, and reads their symbols.
3836 The `share' command is no longer needed. This also works when
3837 examining core files.
3841 You can specify the number of lines that the `list' command shows.
3844 * New machines supported (host and target)
3846 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3847 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3848 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3850 * New hosts supported (not targets)
3852 IBM RT/PC: romp-ibm-aix or rtpc
3854 * New targets supported (not hosts)
3856 AMD 29000 embedded with COFF a29k-none-coff
3857 AMD 29000 embedded with a.out a29k-none-aout
3858 Ultracomputer remote kernel debug a29k-nyu-kern
3860 * New remote interfaces
3866 *** Changes in GDB-4.0:
3870 Wide output is wrapped at good places to make the output more readable.
3872 Gdb now supports cross-debugging from a host machine of one type to a
3873 target machine of another type. Communication with the target system
3874 is over serial lines. The ``target'' command handles connecting to the
3875 remote system; the ``load'' command will download a program into the
3876 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3877 also supports debugging of realtime processes running under VxWorks,
3878 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3879 stub on the target system.
3881 New CPUs supported include the AMD 29000 and Intel 960.
3883 GDB now reads object files and symbol tables via a ``binary file''
3884 library, which allows a single copy of GDB to debug programs of multiple
3885 object file types such as a.out and coff.
3887 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3888 refcard.dvi and refcard.ps are available to format it).
3891 * Control-Variable user interface simplified
3893 All variables that control the operation of the debugger can be set
3894 by the ``set'' command, and displayed by the ``show'' command.
3896 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3897 ``Show prompt'' produces the response:
3898 Gdb's prompt is new-gdb=>.
3900 What follows are the NEW set commands. The command ``help set'' will
3901 print a complete list of old and new set commands. ``help set FOO''
3902 will give a longer description of the variable FOO. ``show'' will show
3903 all of the variable descriptions and their current settings.
3905 confirm on/off: Enables warning questions for operations that are
3906 hard to recover from, e.g. rerunning the program while
3907 it is already running. Default is ON.
3909 editing on/off: Enables EMACS style command line editing
3910 of input. Previous lines can be recalled with
3911 control-P, the current line can be edited with control-B,
3912 you can search for commands with control-R, etc.
3915 history filename NAME: NAME is where the gdb command history
3916 will be stored. The default is .gdb_history,
3917 or the value of the environment variable
3920 history size N: The size, in commands, of the command history. The
3921 default is 256, or the value of the environment variable
3924 history save on/off: If this value is set to ON, the history file will
3925 be saved after exiting gdb. If set to OFF, the
3926 file will not be saved. The default is OFF.
3928 history expansion on/off: If this value is set to ON, then csh-like
3929 history expansion will be performed on
3930 command line input. The default is OFF.
3932 radix N: Sets the default radix for input and output. It can be set
3933 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3934 in the current radix, so "set radix 10" is always a no-op.
3936 height N: This integer value is the number of lines on a page. Default
3937 is 24, the current `stty rows'' setting, or the ``li#''
3938 setting from the termcap entry matching the environment
3941 width N: This integer value is the number of characters on a line.
3942 Default is 80, the current `stty cols'' setting, or the ``co#''
3943 setting from the termcap entry matching the environment
3946 Note: ``set screensize'' is obsolete. Use ``set height'' and
3947 ``set width'' instead.
3949 print address on/off: Print memory addresses in various command displays,
3950 such as stack traces and structure values. Gdb looks
3951 more ``symbolic'' if you turn this off; it looks more
3952 ``machine level'' with it on. Default is ON.
3954 print array on/off: Prettyprint arrays. New convenient format! Default
3957 print demangle on/off: Print C++ symbols in "source" form if on,
3960 print asm-demangle on/off: Same, for assembler level printouts
3963 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3966 * Support for Epoch Environment.
3968 The epoch environment is a version of Emacs v18 with windowing. One
3969 new command, ``inspect'', is identical to ``print'', except that if you
3970 are running in the epoch environment, the value is printed in its own
3974 * Support for Shared Libraries
3976 GDB can now debug programs and core files that use SunOS shared libraries.
3977 Symbols from a shared library cannot be referenced
3978 before the shared library has been linked with the program (this
3979 happens after you type ``run'' and before the function main() is entered).
3980 At any time after this linking (including when examining core files
3981 from dynamically linked programs), gdb reads the symbols from each
3982 shared library when you type the ``sharedlibrary'' command.
3983 It can be abbreviated ``share''.
3985 sharedlibrary REGEXP: Load shared object library symbols for files
3986 matching a unix regular expression. No argument
3987 indicates to load symbols for all shared libraries.
3989 info sharedlibrary: Status of loaded shared libraries.
3994 A watchpoint stops execution of a program whenever the value of an
3995 expression changes. Checking for this slows down execution
3996 tremendously whenever you are in the scope of the expression, but is
3997 quite useful for catching tough ``bit-spreader'' or pointer misuse
3998 problems. Some machines such as the 386 have hardware for doing this
3999 more quickly, and future versions of gdb will use this hardware.
4001 watch EXP: Set a watchpoint (breakpoint) for an expression.
4003 info watchpoints: Information about your watchpoints.
4005 delete N: Deletes watchpoint number N (same as breakpoints).
4006 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4007 enable N: Re-enables watchpoint number N (same as breakpoints).
4010 * C++ multiple inheritance
4012 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4015 * C++ exception handling
4017 Gdb now supports limited C++ exception handling. Besides the existing
4018 ability to breakpoint on an exception handler, gdb can breakpoint on
4019 the raising of an exception (before the stack is peeled back to the
4022 catch FOO: If there is a FOO exception handler in the dynamic scope,
4023 set a breakpoint to catch exceptions which may be raised there.
4024 Multiple exceptions (``catch foo bar baz'') may be caught.
4026 info catch: Lists all exceptions which may be caught in the
4027 current stack frame.
4030 * Minor command changes
4032 The command ``call func (arg, arg, ...)'' now acts like the print
4033 command, except it does not print or save a value if the function's result
4034 is void. This is similar to dbx usage.
4036 The ``up'' and ``down'' commands now always print the frame they end up
4037 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4038 frames without printing.
4040 * New directory command
4042 'dir' now adds directories to the FRONT of the source search path.
4043 The path starts off empty. Source files that contain debug information
4044 about the directory in which they were compiled can be found even
4045 with an empty path; Sun CC and GCC include this information. If GDB can't
4046 find your source file in the current directory, type "dir .".
4048 * Configuring GDB for compilation
4050 For normal use, type ``./configure host''. See README or gdb.texinfo
4053 GDB now handles cross debugging. If you are remotely debugging between
4054 two different machines, type ``./configure host -target=targ''.
4055 Host is the machine where GDB will run; targ is the machine
4056 where the program that you are debugging will run.