1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.1
6 * Windows Thread Information Block access.
8 On Windows targets, GDB now supports displaying the Windows Thread
9 Information Block (TIB) structure. This structure is visible either
10 by using the new command `info w32 thread-information-block' or, by
11 dereferencing the new convenience variable named `$_tlb', a
12 thread-specific pointer to the TIB. This feature is also supported
13 when remote debugging using GDBserver.
19 Return the address of the Windows Thread Information Block of a given thread.
21 * The source command now accepts a -s option to force searching for the
22 script in the source search path even if the script name specifies
25 * New features in the GDB remote stub, GDBserver
27 - GDBserver now support tracepoints. The feature is currently
28 supported by the i386-linux and amd64-linux builds.
30 * GDB now sends xmlRegisters= in qSupported packet to indicate that
31 it understands register description.
33 * The --batch flag now disables pagination and queries.
35 * X86 general purpose registers
37 GDB now supports reading/writing byte, word and double-word x86
38 general purpose registers directly. This means you can use, say,
39 $ah or $ax to refer, respectively, to the byte register AH and
40 16-bit word register AX that are actually portions of the 32-bit
41 register EAX or 64-bit register RAX.
43 * The `commands' command now accepts a range of breakpoints to modify.
44 A plain `commands' following a command that creates multiple
45 breakpoints affects all the breakpoints set by that command. This
46 applies to breakpoints set by `rbreak', and also applies when a
47 single `break' command creates multiple breakpoints (e.g.,
48 breakpoints on overloaded c++ functions).
50 * The `rbreak' command now accepts a filename specification as part of
51 its argument, limiting the functions selected by the regex to those
52 in the specified file.
56 save breakpoints <filename>
57 Save all current breakpoint definitions to a file suitable for use
58 in a later debugging session. To read the saved breakpoint
59 definitions, use the `source' command.
61 `save tracepoints' is a new alias for `save-tracepoints'. The latter
66 ** The GDB Python API now has access to breakpoints, symbols, symbol
67 tables, program spaces, and frame's code blocks.
69 ** New functions gdb.target_charset, gdb.target_wide_charset,
70 gdb.progspaces, and gdb.current_progspace.
72 ** Pretty-printers are now also looked up in the current program space.
74 ** GDB now looks for names of Python scripts to auto-load in a
75 special section named `.debug_gdb_scripts', in addition to looking
76 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
78 * Tracepoint actions were unified with breakpoint commands. In particular,
79 there are no longer differences in "info break" output for breakpoints and
80 tracepoints and the "commands" command can be used for both tracepoints and
85 ARM Symbian arm*-*-symbianelf*
87 *** Changes in GDB 7.1
93 GDB now supports importing of namespaces in C++. This enables the
94 user to inspect variables from imported namespaces. Support for
95 namepace aliasing has also been added. So, if a namespace is
96 aliased in the current scope (e.g. namepace C=A; ) the user can
97 print variables using the alias (e.g. (gdb) print C::x).
101 All known bugs relating to the printing of virtual base class were
102 fixed. It is now possible to call overloaded static methods using a
107 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
108 and reinterpret_cast<> are now handled by the C++ expression parser.
112 Xilinx MicroBlaze microblaze-*-*
117 Xilinx MicroBlaze microblaze
120 * Multi-program debugging.
122 GDB now has support for multi-program (a.k.a. multi-executable or
123 multi-exec) debugging. This allows for debugging multiple inferiors
124 simultaneously each running a different program under the same GDB
125 session. See "Debugging Multiple Inferiors and Programs" in the
126 manual for more information. This implied some user visible changes
127 in the multi-inferior support. For example, "info inferiors" now
128 lists inferiors that are not running yet or that have exited
129 already. See also "New commands" and "New options" below.
131 * New tracing features
133 GDB's tracepoint facility now includes several new features:
135 ** Trace state variables
137 GDB tracepoints now include support for trace state variables, which
138 are variables managed by the target agent during a tracing
139 experiment. They are useful for tracepoints that trigger each
140 other, so for instance one tracepoint can count hits in a variable,
141 and then a second tracepoint has a condition that is true when the
142 count reaches a particular value. Trace state variables share the
143 $-syntax of GDB convenience variables, and can appear in both
144 tracepoint actions and condition expressions. Use the "tvariable"
145 command to create, and "info tvariables" to view; see "Trace State
146 Variables" in the manual for more detail.
150 GDB now includes an option for defining fast tracepoints, which
151 targets may implement more efficiently, such as by installing a jump
152 into the target agent rather than a trap instruction. The resulting
153 speedup can be by two orders of magnitude or more, although the
154 tradeoff is that some program locations on some target architectures
155 might not allow fast tracepoint installation, for instance if the
156 instruction to be replaced is shorter than the jump. To request a
157 fast tracepoint, use the "ftrace" command, with syntax identical to
158 the regular trace command.
160 ** Disconnected tracing
162 It is now possible to detach GDB from the target while it is running
163 a trace experiment, then reconnect later to see how the experiment
164 is going. In addition, a new variable disconnected-tracing lets you
165 tell the target agent whether to continue running a trace if the
166 connection is lost unexpectedly.
170 GDB now has the ability to save the trace buffer into a file, and
171 then use that file as a target, similarly to you can do with
172 corefiles. You can select trace frames, print data that was
173 collected in them, and use tstatus to display the state of the
174 tracing run at the moment that it was saved. To create a trace
175 file, use "tsave <filename>", and to use it, do "target tfile
178 ** Circular trace buffer
180 You can ask the target agent to handle the trace buffer as a
181 circular buffer, discarding the oldest trace frames to make room for
182 newer ones, by setting circular-trace-buffer to on. This feature may
183 not be available for all target agents.
188 The disassemble command, when invoked with two arguments, now requires
189 the arguments to be comma-separated.
192 The info variables command now displays variable definitions. Files
193 which only declare a variable are not shown.
196 The source command is now capable of sourcing Python scripts.
197 This feature is dependent on the debugger being build with Python
200 Related to this enhancement is also the introduction of a new command
201 "set script-extension" (see below).
203 * New commands (for set/show, see "New options" below)
205 record save [<FILENAME>]
206 Save a file (in core file format) containing the process record
207 execution log for replay debugging at a later time.
209 record restore <FILENAME>
210 Restore the process record execution log that was saved at an
211 earlier time, for replay debugging.
213 add-inferior [-copies <N>] [-exec <FILENAME>]
216 clone-inferior [-copies <N>] [ID]
217 Make a new inferior ready to execute the same program another
223 maint info program-spaces
224 List the program spaces loaded into GDB.
226 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
227 show remote interrupt-sequence
228 Allow the user to select one of ^C, a BREAK signal or BREAK-g
229 as the sequence to the remote target in order to interrupt the execution.
230 Ctrl-C is a default. Some system prefers BREAK which is high level of
231 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
232 Magic SysRq g. It is BREAK signal and character 'g'.
234 set remote interrupt-on-connect [on | off]
235 show remote interrupt-on-connect
236 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
237 remote target when gdb connects to it. This is needed when you debug
240 set remotebreak [on | off]
242 Deprecated. Use "set/show remote interrupt-sequence" instead.
244 tvariable $NAME [ = EXP ]
245 Create or modify a trace state variable.
248 List trace state variables and their values.
250 delete tvariable $NAME ...
251 Delete one or more trace state variables.
254 Evaluate the given expressions without collecting anything into the
255 trace buffer. (Valid in tracepoint actions only.)
257 ftrace FN / FILE:LINE / *ADDR
258 Define a fast tracepoint at the given function, line, or address.
260 * New expression syntax
262 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
263 GDB now parses 0b101010 identically with 42.
267 set follow-exec-mode new|same
268 show follow-exec-mode
269 Control whether GDB reuses the same inferior across an exec call or
270 creates a new one. This is useful to be able to restart the old
271 executable after the inferior having done an exec call.
273 set default-collect EXPR, ...
275 Define a list of expressions to be collected at each tracepoint.
276 This is a useful way to ensure essential items are not overlooked,
277 such as registers or a critical global variable.
279 set disconnected-tracing
280 show disconnected-tracing
281 If set to 1, the target is instructed to continue tracing if it
282 loses its connection to GDB. If 0, the target is to stop tracing
285 set circular-trace-buffer
286 show circular-trace-buffer
287 If set to on, the target is instructed to use a circular trace buffer
288 and discard the oldest trace frames instead of stopping the trace due
289 to a full trace buffer. If set to off, the trace stops when the buffer
290 fills up. Some targets may not support this.
292 set script-extension off|soft|strict
293 show script-extension
294 If set to "off", the debugger does not perform any script language
295 recognition, and all sourced files are assumed to be GDB scripts.
296 If set to "soft" (the default), files are sourced according to
297 filename extension, falling back to GDB scripts if the first
299 If set to "strict", files are sourced according to filename extension.
301 set ada trust-PAD-over-XVS on|off
302 show ada trust-PAD-over-XVS
303 If off, activate a workaround against a bug in the debugging information
304 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
305 the GCC sources for more information about the GNAT encoding and
306 PAD types in particular). It is always safe to set this option to
307 off, but this introduces a slight performance penalty. The default
310 * Python API Improvements
312 ** GDB provides the new class gdb.LazyString. This is useful in
313 some pretty-printing cases. The new method gdb.Value.lazy_string
314 provides a simple way to create objects of this type.
316 ** The fields returned by gdb.Type.fields now have an
317 `is_base_class' attribute.
319 ** The new method gdb.Type.range returns the range of an array type.
321 ** The new method gdb.parse_and_eval can be used to parse and
322 evaluate an expression.
327 Define a trace state variable.
330 Get the current value of a trace state variable.
333 Set desired tracing behavior upon disconnection.
336 Set the trace buffer to be linear or circular.
339 Get data about the tracepoints currently in use.
343 Process record now works correctly with hardware watchpoints.
345 Multiple bug fixes have been made to the mips-irix port, making it
346 much more reliable. In particular:
347 - Debugging threaded applications is now possible again. Previously,
348 GDB would hang while starting the program, or while waiting for
349 the program to stop at a breakpoint.
350 - Attaching to a running process no longer hangs.
351 - An error occurring while loading a core file has been fixed.
352 - Changing the value of the PC register now works again. This fixes
353 problems observed when using the "jump" command, or when calling
354 a function from GDB, or even when assigning a new value to $pc.
355 - With the "finish" and "return" commands, the return value for functions
356 returning a small array is now correctly printed.
357 - It is now possible to break on shared library code which gets executed
358 during a shared library init phase (code executed while executing
359 their .init section). Previously, the breakpoint would have no effect.
360 - GDB is now able to backtrace through the signal handler for
361 non-threaded programs.
363 PIE (Position Independent Executable) programs debugging is now supported.
364 This includes debugging execution of PIC (Position Independent Code) shared
365 libraries although for that, it should be possible to run such libraries as an
368 *** Changes in GDB 7.0
370 * GDB now has an interface for JIT compilation. Applications that
371 dynamically generate code can create symbol files in memory and register
372 them with GDB. For users, the feature should work transparently, and
373 for JIT developers, the interface is documented in the GDB manual in the
374 "JIT Compilation Interface" chapter.
376 * Tracepoints may now be conditional. The syntax is as for
377 breakpoints; either an "if" clause appended to the "trace" command,
378 or the "condition" command is available. GDB sends the condition to
379 the target for evaluation using the same bytecode format as is used
380 for tracepoint actions.
382 * "disassemble" command with a /r modifier, print the raw instructions
383 in hex as well as in symbolic form.
385 * Process record and replay
387 In a architecture environment that supports ``process record and
388 replay'', ``process record and replay'' target can record a log of
389 the process execution, and replay it with both forward and reverse
392 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
393 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
394 set execution-direction {forward|reverse}, for targets that support
397 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
398 feature is available with a native GDB running on kernel version
401 * GDB now has support for multi-byte and wide character sets on the
402 target. Strings whose character type is wchar_t, char16_t, or
403 char32_t are now correctly printed. GDB supports wide- and unicode-
404 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
405 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
406 `printf'. This feature requires iconv to work properly; if your
407 system does not have a working iconv, GDB can use GNU libiconv. See
408 the installation instructions for more information.
410 * GDB now supports automatic retrieval of shared library files from
411 remote targets. To use this feature, specify a system root that begins
412 with the `remote:' prefix, either via the `set sysroot' command or via
413 the `--with-sysroot' configure-time option.
415 * "info sharedlibrary" now takes an optional regex of libraries to show,
416 and it now reports if a shared library has no debugging information.
418 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
419 now complete on file names.
421 * When completing in expressions, gdb will attempt to limit
422 completions to allowable structure or union fields, where appropriate.
423 For instance, consider:
425 # struct example { int f1; double f2; };
426 # struct example variable;
429 If the user types TAB at the end of this command line, the available
430 completions will be "f1" and "f2".
432 * Inlined functions are now supported. They show up in backtraces, and
433 the "step", "next", and "finish" commands handle them automatically.
435 * GDB now supports the token-splicing (##) and stringification (#)
436 operators when expanding macros. It also supports variable-arity
439 * GDB now supports inspecting extra signal information, exported by
440 the new $_siginfo convenience variable. The feature is currently
441 implemented on linux ARM, i386 and amd64.
443 * GDB can now display the VFP floating point registers and NEON vector
444 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
445 can provide these registers (requires Linux 2.6.30 or later). Remote
446 and simulator targets may also provide them.
451 Search memory for a sequence of bytes.
454 Turn off `+'/`-' protocol acknowledgments to permit more efficient
455 operation over reliable transport links. Use of this packet is
456 controlled by the `set remote noack-packet' command.
459 Kill the process with the specified process ID. Use this in preference
460 to `k' when multiprocess protocol extensions are supported.
463 Obtains additional operating system information
467 Read or write additional signal information.
469 * Removed remote protocol undocumented extension
471 An undocumented extension to the remote protocol's `S' stop reply
472 packet that permited the stub to pass a process id was removed.
473 Remote servers should use the `T' stop reply packet instead.
475 * The "disassemble" command now supports an optional /m modifier to print mixed
478 * GDB now supports multiple function calling conventions according to the
479 DWARF-2 DW_AT_calling_convention function attribute.
481 * The SH target utilizes the aforementioned change to distinguish between gcc
482 and Renesas calling convention. It also adds the new CLI commands
483 `set/show sh calling-convention'.
485 * GDB can now read compressed debug sections, as produced by GNU gold
486 with the --compress-debug-sections=zlib flag.
488 * 64-bit core files are now supported on AIX.
490 * Thread switching is now supported on Tru64.
492 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
493 which will be allocated using malloc later in program execution.
495 * The qXfer:libraries:read remote procotol packet now allows passing a
496 list of section offsets.
498 * On GNU/Linux, GDB can now attach to stopped processes. Several race
499 conditions handling signals delivered during attach or thread creation
500 have also been fixed.
502 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
503 From the user's standpoint, all unqualified instances of True and False
504 are treated as the standard definitions, regardless of context.
506 * GDB now parses C++ symbol and type names more flexibly. For
509 template<typename T> class C { };
512 GDB will now correctly handle all of:
514 ptype C<char const *>
516 ptype C<const char *>
519 * New features in the GDB remote stub, gdbserver
521 - The "--wrapper" command-line argument tells gdbserver to use a
522 wrapper program to launch programs for debugging.
524 - On PowerPC and S/390 targets, it is now possible to use a single
525 gdbserver executable to debug both 32-bit and 64-bit programs.
526 (This requires gdbserver itself to be built as a 64-bit executable.)
528 - gdbserver uses the new noack protocol mode for TCP connections to
529 reduce communications latency, if also supported and enabled in GDB.
531 - Support for the sparc64-linux-gnu target is now included in
534 - The amd64-linux build of gdbserver now supports debugging both
535 32-bit and 64-bit programs.
537 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
538 now support hardware watchpoints, and will use them automatically
543 GDB now has support for scripting using Python. Whether this is
544 available is determined at configure time.
546 New GDB commands can now be written in Python.
548 * Ada tasking support
550 Ada tasks can now be inspected in GDB. The following commands have
554 Print the list of Ada tasks.
556 Print detailed information about task number N.
558 Print the task number of the current task.
560 Switch the context of debugging to task number N.
562 * Support for user-defined prefixed commands. The "define" command can
563 add new commands to existing prefixes, e.g. "target".
565 * Multi-inferior, multi-process debugging.
567 GDB now has generalized support for multi-inferior debugging. See
568 "Debugging Multiple Inferiors" in the manual for more information.
569 Although availability still depends on target support, the command
570 set is more uniform now. The GNU/Linux specific multi-forks support
571 has been migrated to this new framework. This implied some user
572 visible changes; see "New commands" and also "Removed commands"
575 * Target descriptions can now describe the target OS ABI. See the
576 "Target Description Format" section in the user manual for more
579 * Target descriptions can now describe "compatible" architectures
580 to indicate that the target can execute applications for a different
581 architecture in addition to those for the main target architecture.
582 See the "Target Description Format" section in the user manual for
585 * Multi-architecture debugging.
587 GDB now includes general supports for debugging applications on
588 hybrid systems that use more than one single processor architecture
589 at the same time. Each such hybrid architecture still requires
590 specific support to be added. The only hybrid architecture supported
591 in this version of GDB is the Cell Broadband Engine.
593 * GDB now supports integrated debugging of Cell/B.E. applications that
594 use both the PPU and SPU architectures. To enable support for hybrid
595 Cell/B.E. debugging, you need to configure GDB to support both the
596 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
597 --enable-targets configure option.
599 * Non-stop mode debugging.
601 For some targets, GDB now supports an optional mode of operation in
602 which you can examine stopped threads while other threads continue
603 to execute freely. This is referred to as non-stop mode, with the
604 old mode referred to as all-stop mode. See the "Non-Stop Mode"
605 section in the user manual for more information.
607 To be able to support remote non-stop debugging, a remote stub needs
608 to implement the non-stop mode remote protocol extensions, as
609 described in the "Remote Non-Stop" section of the user manual. The
610 GDB remote stub, gdbserver, has been adjusted to support these
611 extensions on linux targets.
613 * New commands (for set/show, see "New options" below)
615 catch syscall [NAME(S) | NUMBER(S)]
616 Catch system calls. Arguments, which should be names of system
617 calls or their numbers, mean catch only those syscalls. Without
618 arguments, every syscall will be caught. When the inferior issues
619 any of the specified syscalls, GDB will stop and announce the system
620 call, both when it is called and when its call returns. This
621 feature is currently available with a native GDB running on the
622 Linux Kernel, under the following architectures: x86, x86_64,
623 PowerPC and PowerPC64.
625 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
627 Search memory for a sequence of bytes.
629 maint set python print-stack
630 maint show python print-stack
631 Show a stack trace when an error is encountered in a Python script.
634 Invoke CODE by passing it to the Python interpreter.
639 These allow macros to be defined, undefined, and listed
643 Show operating system information about processes.
646 List the inferiors currently under GDB's control.
649 Switch focus to inferior number NUM.
652 Detach from inferior number NUM.
655 Kill inferior number NUM.
660 show spu stop-on-load
661 Control whether to stop for new SPE threads during Cell/B.E. debugging.
663 set spu auto-flush-cache
664 show spu auto-flush-cache
665 Control whether to automatically flush the software-managed cache
666 during Cell/B.E. debugging.
668 set sh calling-convention
669 show sh calling-convention
670 Control the calling convention used when calling SH target functions.
674 Control display of timestamps with GDB debugging output.
676 set disassemble-next-line
677 show disassemble-next-line
678 Control display of disassembled source lines or instructions when
681 set remote noack-packet
682 show remote noack-packet
683 Set/show the use of remote protocol QStartNoAckMode packet. See above
684 under "New remote packets."
686 set remote query-attached-packet
687 show remote query-attached-packet
688 Control use of remote protocol `qAttached' (query-attached) packet.
690 set remote read-siginfo-object
691 show remote read-siginfo-object
692 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
695 set remote write-siginfo-object
696 show remote write-siginfo-object
697 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
700 set remote reverse-continue
701 show remote reverse-continue
702 Control use of remote protocol 'bc' (reverse-continue) packet.
704 set remote reverse-step
705 show remote reverse-step
706 Control use of remote protocol 'bs' (reverse-step) packet.
708 set displaced-stepping
709 show displaced-stepping
710 Control displaced stepping mode. Displaced stepping is a way to
711 single-step over breakpoints without removing them from the debuggee.
712 Also known as "out-of-line single-stepping".
716 Control display of debugging info for displaced stepping.
718 maint set internal-error
719 maint show internal-error
720 Control what GDB does when an internal error is detected.
722 maint set internal-warning
723 maint show internal-warning
724 Control what GDB does when an internal warning is detected.
729 Use a wrapper program to launch programs for debugging.
731 set multiple-symbols (all|ask|cancel)
732 show multiple-symbols
733 The value of this variable can be changed to adjust the debugger behavior
734 when an expression or a breakpoint location contains an ambiguous symbol
735 name (an overloaded function name, for instance).
737 set breakpoint always-inserted
738 show breakpoint always-inserted
739 Keep breakpoints always inserted in the target, as opposed to inserting
740 them when resuming the target, and removing them when the target stops.
741 This option can improve debugger performance on slow remote targets.
743 set arm fallback-mode (arm|thumb|auto)
744 show arm fallback-mode
745 set arm force-mode (arm|thumb|auto)
747 These commands control how ARM GDB determines whether instructions
748 are ARM or Thumb. The default for both settings is auto, which uses
749 the current CPSR value for instructions without symbols; previous
750 versions of GDB behaved as if "set arm fallback-mode arm".
752 set disable-randomization
753 show disable-randomization
754 Standalone programs run with the virtual address space randomization enabled
755 by default on some platforms. This option keeps the addresses stable across
756 multiple debugging sessions.
760 Control whether other threads are stopped or not when some thread hits
765 Requests that asynchronous execution is enabled in the target, if available.
766 In this case, it's possible to resume target in the background, and interact
767 with GDB while the target is running. "show target-async" displays the
768 current state of asynchronous execution of the target.
770 set target-wide-charset
771 show target-wide-charset
772 The target-wide-charset is the name of the character set that GDB
773 uses when printing characters whose type is wchar_t.
775 set tcp auto-retry (on|off)
777 set tcp connect-timeout
778 show tcp connect-timeout
779 These commands allow GDB to retry failed TCP connections to a remote stub
780 with a specified timeout period; this is useful if the stub is launched
781 in parallel with GDB but may not be ready to accept connections immediately.
783 set libthread-db-search-path
784 show libthread-db-search-path
785 Control list of directories which GDB will search for appropriate
788 set schedule-multiple (on|off)
789 show schedule-multiple
790 Allow GDB to resume all threads of all processes or only threads of
795 Use more aggressive caching for accesses to the stack. This improves
796 performance of remote debugging (particularly backtraces) without
797 affecting correctness.
799 set interactive-mode (on|off|auto)
800 show interactive-mode
801 Control whether GDB runs in interactive mode (on) or not (off).
802 When in interactive mode, GDB waits for the user to answer all
803 queries. Otherwise, GDB does not wait and assumes the default
804 answer. When set to auto (the default), GDB determines which
805 mode to use based on the stdin settings.
810 For program forks, this is replaced by the new more generic `info
811 inferiors' command. To list checkpoints, you can still use the
812 `info checkpoints' command, which was an alias for the `info forks'
816 Replaced by the new `inferior' command. To switch between
817 checkpoints, you can still use the `restart' command, which was an
818 alias for the `fork' command.
821 This is removed, since some targets don't have a notion of
822 processes. To switch between processes, you can still use the
823 `inferior' command using GDB's own inferior number.
826 For program forks, this is replaced by the new more generic `kill
827 inferior' command. To delete a checkpoint, you can still use the
828 `delete checkpoint' command, which was an alias for the `delete
832 For program forks, this is replaced by the new more generic `detach
833 inferior' command. To detach a checkpoint, you can still use the
834 `detach checkpoint' command, which was an alias for the `detach
837 * New native configurations
839 x86/x86_64 Darwin i[34567]86-*-darwin*
841 x86_64 MinGW x86_64-*-mingw*
845 Lattice Mico32 lm32-*
846 x86 DICOS i[34567]86-*-dicos*
847 x86_64 DICOS x86_64-*-dicos*
850 * The GDB remote stub, gdbserver, now supports x86 Windows CE
851 (mingw32ce) debugging.
857 These commands were actually not implemented on any target.
859 *** Changes in GDB 6.8
861 * New native configurations
863 NetBSD/hppa hppa*-*netbsd*
864 Xtensa GNU/Linux xtensa*-*-linux*
868 NetBSD/hppa hppa*-*-netbsd*
869 Xtensa GNU/Lunux xtensa*-*-linux*
871 * Change in command line behavior -- corefiles vs. process ids.
873 When the '-p NUMBER' or '--pid NUMBER' options are used, and
874 attaching to process NUMBER fails, GDB no longer attempts to open a
875 core file named NUMBER. Attaching to a program using the -c option
876 is no longer supported. Instead, use the '-p' or '--pid' options.
878 * GDB can now be built as a native debugger for debugging Windows x86
879 (mingw32) Portable Executable (PE) programs.
881 * Pending breakpoints no longer change their number when their address
884 * GDB now supports breakpoints with multiple locations,
885 including breakpoints on C++ constructors, inside C++ templates,
886 and in inlined functions.
888 * GDB's ability to debug optimized code has been improved. GDB more
889 accurately identifies function bodies and lexical blocks that occupy
890 more than one contiguous range of addresses.
892 * Target descriptions can now describe registers for PowerPC.
894 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
895 registers on PowerPC targets.
897 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
898 targets even when the libthread_db library is not available.
900 * The GDB remote stub, gdbserver, now supports the new file transfer
901 commands (remote put, remote get, and remote delete).
903 * The GDB remote stub, gdbserver, now supports run and attach in
904 extended-remote mode.
906 * hppa*64*-*-hpux11* target broken
907 The debugger is unable to start a program and fails with the following
908 error: "Error trying to get information about dynamic linker".
909 The gdb-6.7 release is also affected.
911 * GDB now supports the --enable-targets= configure option to allow
912 building a single GDB executable that supports multiple remote
913 target architectures.
915 * GDB now supports debugging C and C++ programs which use the
916 Decimal Floating Point extension. In addition, the PowerPC target
917 now has a set of pseudo-registers to inspect decimal float values
918 stored in two consecutive float registers.
920 * The -break-insert MI command can optionally create pending
923 * Improved support for debugging Ada
924 Many improvements to the Ada language support have been made. These
926 - Better support for Ada2005 interface types
927 - Improved handling of arrays and slices in general
928 - Better support for Taft-amendment types
929 - The '{type} ADDRESS' expression is now allowed on the left hand-side
931 - Improved command completion in Ada
934 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
939 set print frame-arguments (all|scalars|none)
940 show print frame-arguments
941 The value of this variable can be changed to control which argument
942 values should be printed by the debugger when displaying a frame.
947 Transfer files to and from a remote target, and delete remote files.
954 Transfer files to and from a remote target, and delete remote files.
963 Open, close, read, write, and delete files on the remote system.
966 Attach to an existing process on the remote system, in extended-remote
970 Run a new process on the remote system, in extended-remote mode.
972 *** Changes in GDB 6.7
974 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
975 bfd, libiberty and opcodes, as revealed by static analysis donated by
976 Coverity, Inc. (http://scan.coverity.com).
978 * When looking up multiply-defined global symbols, GDB will now prefer the
979 symbol definition in the current shared library if it was built using the
980 -Bsymbolic linker option.
982 * When the Text User Interface (TUI) is not configured, GDB will now
983 recognize the -tui command-line option and print a message that the TUI
986 * The GDB remote stub, gdbserver, now has lower overhead for high
987 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
989 * GDB for MIPS targets now autodetects whether a remote target provides
990 32-bit or 64-bit register values.
992 * Support for C++ member pointers has been improved.
994 * GDB now understands XML target descriptions, which specify the
995 target's overall architecture. GDB can read a description from
996 a local file or over the remote serial protocol.
998 * Vectors of single-byte data use a new integer type which is not
999 automatically displayed as character or string data.
1001 * The /s format now works with the print command. It displays
1002 arrays of single-byte integers and pointers to single-byte integers
1005 * Target descriptions can now describe target-specific registers,
1006 for architectures which have implemented the support (currently
1007 only ARM, M68K, and MIPS).
1009 * GDB and the GDB remote stub, gdbserver, now support the XScale
1012 * The GDB remote stub, gdbserver, has been updated to support
1013 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1014 has been rewritten to use the standard GDB remote protocol.
1016 * GDB can now step into C++ functions which are called through thunks.
1018 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1020 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1021 layout. It also supports a TextSeg= and DataSeg= response when only
1022 segment base addresses (rather than offsets) are available.
1024 * The /i format now outputs any trailing branch delay slot instructions
1025 immediately following the last instruction within the count specified.
1027 * The GDB remote protocol "T" stop reply packet now supports a
1028 "library" response. Combined with the new "qXfer:libraries:read"
1029 packet, this response allows GDB to debug shared libraries on targets
1030 where the operating system manages the list of loaded libraries (e.g.
1031 Windows and SymbianOS).
1033 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1034 (DLLs) on Windows and Windows CE targets.
1036 * GDB now supports a faster verification that a .debug file matches its binary
1037 according to its build-id signature, if the signature is present.
1043 Enable or disable hardware flow control (RTS/CTS) on the serial port
1044 when debugging using remote targets.
1046 set mem inaccessible-by-default
1047 show mem inaccessible-by-default
1048 If the target supplies a memory map, for instance via the remote
1049 protocol's "qXfer:memory-map:read" packet, setting this variable
1050 prevents GDB from accessing memory outside the memory map. This
1051 is useful for targets with memory mapped registers or which react
1052 badly to accesses of unmapped address space.
1054 set breakpoint auto-hw
1055 show breakpoint auto-hw
1056 If the target supplies a memory map, for instance via the remote
1057 protocol's "qXfer:memory-map:read" packet, setting this variable
1058 lets GDB use hardware breakpoints automatically for memory regions
1059 where it can not use software breakpoints. This covers both the
1060 "break" command and internal breakpoints used for other commands
1061 including "next" and "finish".
1064 catch exception unhandled
1065 Stop the program execution when Ada exceptions are raised.
1068 Stop the program execution when an Ada assertion failed.
1072 Set an alternate system root for target files. This is a more
1073 general version of "set solib-absolute-prefix", which is now
1074 an alias to "set sysroot".
1077 Provide extended SPU facility status information. This set of
1078 commands is available only when debugging the Cell/B.E. SPU
1081 * New native configurations
1083 OpenBSD/sh sh*-*openbsd*
1086 unset tdesc filename
1088 Use the specified local file as an XML target description, and do
1089 not query the target for its built-in description.
1093 OpenBSD/sh sh*-*-openbsd*
1094 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1095 Toshiba Media Processor mep-elf
1097 * New remote packets
1100 Ignore the specified signals; pass them directly to the debugged program
1101 without stopping other threads or reporting them to GDB.
1103 qXfer:features:read:
1104 Read an XML target description from the target, which describes its
1109 Read or write contents of an spufs file on the target system. These
1110 packets are available only on the Cell/B.E. SPU architecture.
1112 qXfer:libraries:read:
1113 Report the loaded shared libraries. Combined with new "T" packet
1114 response, this packet allows GDB to debug shared libraries on
1115 targets where the operating system manages the list of loaded
1116 libraries (e.g. Windows and SymbianOS).
1120 Support for these obsolete configurations has been removed.
1128 i[34567]86-*-lynxos*
1129 i[34567]86-*-netware*
1130 i[34567]86-*-sco3.2v5*
1131 i[34567]86-*-sco3.2v4*
1133 i[34567]86-*-sysv4.2*
1136 i[34567]86-*-unixware2*
1137 i[34567]86-*-unixware*
1146 * Other removed features
1153 Various m68k-only ROM monitors.
1160 Various Renesas ROM monitors and debugging interfaces for SH and
1165 Support for a Macraigor serial interface to on-chip debugging.
1166 GDB does not directly support the newer parallel or USB
1171 A debug information format. The predecessor to DWARF 2 and
1172 DWARF 3, which are still supported.
1174 Support for the HP aCC compiler on HP-UX/PA-RISC
1176 SOM-encapsulated symbolic debugging information, automatic
1177 invocation of pxdb, and the aCC custom C++ ABI. This does not
1178 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1179 with aCC can still be debugged on an assembly level.
1181 MIPS ".pdr" sections
1183 A MIPS-specific format used to describe stack frame layout
1184 in debugging information.
1188 GDB could work with an older version of Guile to debug
1189 the interpreter and Scheme programs running in it.
1191 set mips stack-arg-size
1192 set mips saved-gpreg-size
1194 Use "set mips abi" to control parameter passing for MIPS.
1196 *** Changes in GDB 6.6
1201 Cell Broadband Engine SPU spu-elf
1203 * GDB can now be configured as a cross-debugger targeting native Windows
1204 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1205 running on a Windows system over TCP/IP to debug Windows programs.
1207 * The GDB remote stub, gdbserver, has been updated to support Windows and
1208 Cygwin debugging. Both single-threaded and multi-threaded programs are
1211 * The "set trust-readonly-sections" command works again. This command was
1212 broken in GDB 6.3, 6.4, and 6.5.
1214 * The "load" command now supports writing to flash memory, if the remote
1215 stub provides the required support.
1217 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1218 longer requires symbolic debug information (e.g. DWARF-2).
1223 unset substitute-path
1224 show substitute-path
1225 Manage a list of substitution rules that GDB uses to rewrite the name
1226 of the directories where the sources are located. This can be useful
1227 for instance when the sources were moved to a different location
1228 between compilation and debugging.
1232 Print each CLI command as it is executed. Each command is prefixed with
1233 a number of `+' symbols representing the nesting depth.
1234 The source command now has a `-v' option to enable the same feature.
1238 The ARM Demon monitor support (RDP protocol, "target rdp").
1240 Kernel Object Display, an embedded debugging feature which only worked with
1241 an obsolete version of Cisco IOS.
1243 The 'set download-write-size' and 'show download-write-size' commands.
1245 * New remote packets
1248 Tell a stub about GDB client features, and request remote target features.
1249 The first feature implemented is PacketSize, which allows the target to
1250 specify the size of packets it can handle - to minimize the number of
1251 packets required and improve performance when connected to a remote
1255 Fetch an OS auxilliary vector from the remote stub. This packet is a
1256 more efficient replacement for qPart:auxv:read.
1258 qXfer:memory-map:read:
1259 Fetch a memory map from the remote stub, including information about
1260 RAM, ROM, and flash memory devices.
1265 Erase and program a flash memory device.
1267 * Removed remote packets
1270 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1271 used it, and only gdbserver implemented it.
1273 *** Changes in GDB 6.5
1277 Renesas M32C/M16C m32c-elf
1279 Morpho Technologies ms1 ms1-elf
1283 init-if-undefined Initialize a convenience variable, but
1284 only if it doesn't already have a value.
1286 The following commands are presently only implemented for native GNU/Linux:
1288 checkpoint Save a snapshot of the program state.
1290 restart <n> Return the program state to a
1291 previously saved state.
1293 info checkpoints List currently saved checkpoints.
1295 delete-checkpoint <n> Delete a previously saved checkpoint.
1297 set|show detach-on-fork Tell gdb whether to detach from a newly
1298 forked process, or to keep debugging it.
1300 info forks List forks of the user program that
1301 are available to be debugged.
1303 fork <n> Switch to debugging one of several
1304 forks of the user program that are
1305 available to be debugged.
1307 delete-fork <n> Delete a fork from the list of forks
1308 that are available to be debugged (and
1309 kill the forked process).
1311 detach-fork <n> Delete a fork from the list of forks
1312 that are available to be debugged (and
1313 allow the process to continue).
1317 Morpho Technologies ms2 ms1-elf
1319 * Improved Windows host support
1321 GDB now builds as a cross debugger hosted on i686-mingw32, including
1322 native console support, and remote communications using either
1323 network sockets or serial ports.
1325 * Improved Modula-2 language support
1327 GDB can now print most types in the Modula-2 syntax. This includes:
1328 basic types, set types, record types, enumerated types, range types,
1329 pointer types and ARRAY types. Procedure var parameters are correctly
1330 printed and hexadecimal addresses and character constants are also
1331 written in the Modula-2 syntax. Best results can be obtained by using
1332 GNU Modula-2 together with the -gdwarf-2 command line option.
1336 The ARM rdi-share module.
1338 The Netware NLM debug server.
1340 *** Changes in GDB 6.4
1342 * New native configurations
1344 OpenBSD/arm arm*-*-openbsd*
1345 OpenBSD/mips64 mips64-*-openbsd*
1349 Morpho Technologies ms1 ms1-elf
1351 * New command line options
1353 --batch-silent As for --batch, but totally silent.
1354 --return-child-result The debugger will exist with the same value
1355 the child (debugged) program exited with.
1356 --eval-command COMMAND, -ex COMMAND
1357 Execute a single GDB CLI command. This may be
1358 specified multiple times and in conjunction
1359 with the --command (-x) option.
1361 * Deprecated commands removed
1363 The following commands, that were deprecated in 2000, have been
1367 set|show arm disassembly-flavor set|show arm disassembler
1368 othernames set arm disassembler
1369 set|show remotedebug set|show debug remote
1370 set|show archdebug set|show debug arch
1371 set|show eventdebug set|show debug event
1374 * New BSD user-level threads support
1376 It is now possible to debug programs using the user-level threads
1377 library on OpenBSD and FreeBSD. Currently supported (target)
1380 FreeBSD/amd64 x86_64-*-freebsd*
1381 FreeBSD/i386 i386-*-freebsd*
1382 OpenBSD/i386 i386-*-openbsd*
1384 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1385 are not yet supported.
1387 * New support for Matsushita MN10300 w/sim added
1388 (Work in progress). mn10300-elf.
1390 * REMOVED configurations and files
1392 VxWorks and the XDR protocol *-*-vxworks
1393 Motorola MCORE mcore-*-*
1394 National Semiconductor NS32000 ns32k-*-*
1396 * New "set print array-indexes" command
1398 After turning this setting "on", GDB prints the index of each element
1399 when displaying arrays. The default is "off" to preserve the previous
1402 * VAX floating point support
1404 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1406 * User-defined command support
1408 In addition to using $arg0..$arg9 for argument passing, it is now possible
1409 to use $argc to determine now many arguments have been passed. See the
1410 section on user-defined commands in the user manual for more information.
1412 *** Changes in GDB 6.3:
1414 * New command line option
1416 GDB now accepts -l followed by a number to set the timeout for remote
1419 * GDB works with GCC -feliminate-dwarf2-dups
1421 GDB now supports a more compact representation of DWARF-2 debug
1422 information using DW_FORM_ref_addr references. These are produced
1423 by GCC with the option -feliminate-dwarf2-dups and also by some
1424 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1425 to use -feliminate-dwarf2-dups.
1427 * Internationalization
1429 When supported by the host system, GDB will be built with
1430 internationalization (libintl). The task of marking up the sources is
1431 continued, we're looking forward to our first translation.
1435 Initial support for debugging programs compiled with the GNAT
1436 implementation of the Ada programming language has been integrated
1437 into GDB. In this release, support is limited to expression evaluation.
1439 * New native configurations
1441 GNU/Linux/m32r m32r-*-linux-gnu
1445 GDB's remote protocol now includes support for the 'p' packet. This
1446 packet is used to fetch individual registers from a remote inferior.
1448 * END-OF-LIFE registers[] compatibility module
1450 GDB's internal register infrastructure has been completely rewritten.
1451 The new infrastructure making possible the implementation of key new
1452 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1455 GDB 6.3 will be the last release to include the the registers[]
1456 compatibility module that allowed out-of-date configurations to
1457 continue to work. This change directly impacts the following
1467 powerpc bdm protocol
1469 Unless there is activity to revive these configurations, they will be
1470 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1472 * OBSOLETE configurations and files
1474 Configurations that have been declared obsolete in this release have
1475 been commented out. Unless there is activity to revive these
1476 configurations, the next release of GDB will have their sources
1477 permanently REMOVED.
1486 *** Changes in GDB 6.2.1:
1488 * MIPS `break main; run' gave an heuristic-fence-post warning
1490 When attempting to run even a simple program, a warning about
1491 heuristic-fence-post being hit would be reported. This problem has
1494 * MIPS IRIX 'long double' crashed GDB
1496 When examining a long double variable, GDB would get a segmentation
1497 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1498 IRIX long double values).
1502 A bug in the VAX stack code was causing problems with the "next"
1503 command. This problem has been fixed.
1505 *** Changes in GDB 6.2:
1507 * Fix for ``many threads''
1509 On GNU/Linux systems that use the NPTL threads library, a program
1510 rapidly creating and deleting threads would confuse GDB leading to the
1513 ptrace: No such process.
1514 thread_db_get_info: cannot get thread info: generic error
1516 This problem has been fixed.
1518 * "-async" and "-noasync" options removed.
1520 Support for the broken "-noasync" option has been removed (it caused
1523 * New ``start'' command.
1525 This command runs the program until the begining of the main procedure.
1527 * New BSD Kernel Data Access Library (libkvm) interface
1529 Using ``target kvm'' it is now possible to debug kernel core dumps and
1530 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1531 platforms. Currently supported (native-only) configurations are:
1533 FreeBSD/amd64 x86_64-*-freebsd*
1534 FreeBSD/i386 i?86-*-freebsd*
1535 NetBSD/i386 i?86-*-netbsd*
1536 NetBSD/m68k m68*-*-netbsd*
1537 NetBSD/sparc sparc-*-netbsd*
1538 OpenBSD/amd64 x86_64-*-openbsd*
1539 OpenBSD/i386 i?86-*-openbsd*
1540 OpenBSD/m68k m68*-openbsd*
1541 OpenBSD/sparc sparc-*-openbsd*
1543 * Signal trampoline code overhauled
1545 Many generic problems with GDB's signal handling code have been fixed.
1546 These include: backtraces through non-contiguous stacks; recognition
1547 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1548 call; backtrace through a signal trampoline; step into and out of
1549 signal handlers; and single-stepping in the signal trampoline.
1551 Please note that kernel bugs are a limiting factor here. These
1552 features have been shown to work on an s390 GNU/Linux system that
1553 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1555 * Cygwin support for DWARF 2 added.
1557 * New native configurations
1559 GNU/Linux/hppa hppa*-*-linux*
1560 OpenBSD/hppa hppa*-*-openbsd*
1561 OpenBSD/m68k m68*-*-openbsd*
1562 OpenBSD/m88k m88*-*-openbsd*
1563 OpenBSD/powerpc powerpc-*-openbsd*
1564 NetBSD/vax vax-*-netbsd*
1565 OpenBSD/vax vax-*-openbsd*
1567 * END-OF-LIFE frame compatibility module
1569 GDB's internal frame infrastructure has been completely rewritten.
1570 The new infrastructure making it possible to support key new features
1571 including DWARF 2 Call Frame Information. To aid in the task of
1572 migrating old configurations to this new infrastructure, a
1573 compatibility module, that allowed old configurations to continue to
1574 work, was also included.
1576 GDB 6.2 will be the last release to include this frame compatibility
1577 module. This change directly impacts the following configurations:
1587 Unless there is activity to revive these configurations, they will be
1588 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1590 * REMOVED configurations and files
1592 Sun 3, running SunOS 3 m68*-*-sunos3*
1593 Sun 3, running SunOS 4 m68*-*-sunos4*
1594 Sun 2, running SunOS 3 m68000-*-sunos3*
1595 Sun 2, running SunOS 4 m68000-*-sunos4*
1596 Motorola 680x0 running LynxOS m68*-*-lynxos*
1597 AT&T 3b1/Unix pc m68*-att-*
1598 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1599 decstation mips-dec-* mips-little-*
1600 riscos mips-*-riscos* mips-*-sysv*
1601 sonymips mips-sony-*
1602 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1604 *** Changes in GDB 6.1.1:
1606 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1608 The TUI (Text-mode User Interface) is now built as part of a default
1609 GDB configuration. It is enabled by either selecting the TUI with the
1610 command line option "-i=tui" or by running the separate "gdbtui"
1611 program. For more information on the TUI, see the manual "Debugging
1614 * Pending breakpoint support (also included in GDB 6.1)
1616 Support has been added to allow you to specify breakpoints in shared
1617 libraries that have not yet been loaded. If a breakpoint location
1618 cannot be found, and the "breakpoint pending" option is set to auto,
1619 GDB queries you if you wish to make the breakpoint pending on a future
1620 shared-library load. If and when GDB resolves the breakpoint symbol,
1621 the pending breakpoint is removed as one or more regular breakpoints
1624 Pending breakpoints are very useful for GCJ Java debugging.
1626 * Fixed ISO-C build problems
1628 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1629 non ISO-C code that stopped them being built using a more strict ISO-C
1630 compiler (e.g., IBM's C compiler).
1632 * Fixed build problem on IRIX 5
1634 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1635 wasn't able to compile compile on an IRIX 5 system.
1637 * Added execute permission to gdb/gdbserver/configure
1639 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1640 permission. This bug would cause configure to fail on a number of
1641 systems (Solaris, IRIX). Ref: server/519.
1643 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1645 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1646 has been updated to use constant array sizes.
1648 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1650 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1651 its generated DWARF Call Frame Info. This encoding was causing GDB to
1652 panic, that panic has been fixed. Ref: gdb/1628.
1654 * Fixed a problem when examining parameters in shared library code.
1656 When examining parameters in optimized shared library code generated
1657 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1658 not available''. GDB now correctly displays the variable's value.
1660 *** Changes in GDB 6.1:
1662 * Removed --with-mmalloc
1664 Support for the mmalloc memory manager has been removed, as it
1665 conflicted with the internal gdb byte cache.
1667 * Changes in AMD64 configurations
1669 The AMD64 target now includes the %cs and %ss registers. As a result
1670 the AMD64 remote protocol has changed; this affects the floating-point
1671 and SSE registers. If you rely on those registers for your debugging,
1672 you should upgrade gdbserver on the remote side.
1674 * Revised SPARC target
1676 The SPARC target has been completely revised, incorporating the
1677 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1678 support for LynxOS and SunOS 4 has been dropped. Calling functions
1679 from within GDB on operating systems with a non-executable stack
1680 (Solaris, OpenBSD) now works.
1684 GDB has a new C++ demangler which does a better job on the mangled
1685 names generated by current versions of g++. It also runs faster, so
1686 with this and other changes gdb should now start faster on large C++
1689 * DWARF 2 Location Expressions
1691 GDB support for location expressions has been extended to support function
1692 arguments and frame bases. Older versions of GDB could crash when they
1695 * C++ nested types and namespaces
1697 GDB's support for nested types and namespaces in C++ has been
1698 improved, especially if you use the DWARF 2 debugging format. (This
1699 is the default for recent versions of GCC on most platforms.)
1700 Specifically, if you have a class "Inner" defined within a class or
1701 namespace "Outer", then GDB realizes that the class's name is
1702 "Outer::Inner", not simply "Inner". This should greatly reduce the
1703 frequency of complaints about not finding RTTI symbols. In addition,
1704 if you are stopped at inside of a function defined within a namespace,
1705 GDB modifies its name lookup accordingly.
1707 * New native configurations
1709 NetBSD/amd64 x86_64-*-netbsd*
1710 OpenBSD/amd64 x86_64-*-openbsd*
1711 OpenBSD/alpha alpha*-*-openbsd*
1712 OpenBSD/sparc sparc-*-openbsd*
1713 OpenBSD/sparc64 sparc64-*-openbsd*
1715 * New debugging protocols
1717 M32R with SDI protocol m32r-*-elf*
1719 * "set prompt-escape-char" command deleted.
1721 The command "set prompt-escape-char" has been deleted. This command,
1722 and its very obscure effet on GDB's prompt, was never documented,
1723 tested, nor mentioned in the NEWS file.
1725 * OBSOLETE configurations and files
1727 Configurations that have been declared obsolete in this release have
1728 been commented out. Unless there is activity to revive these
1729 configurations, the next release of GDB will have their sources
1730 permanently REMOVED.
1732 Sun 3, running SunOS 3 m68*-*-sunos3*
1733 Sun 3, running SunOS 4 m68*-*-sunos4*
1734 Sun 2, running SunOS 3 m68000-*-sunos3*
1735 Sun 2, running SunOS 4 m68000-*-sunos4*
1736 Motorola 680x0 running LynxOS m68*-*-lynxos*
1737 AT&T 3b1/Unix pc m68*-att-*
1738 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1739 decstation mips-dec-* mips-little-*
1740 riscos mips-*-riscos* mips-*-sysv*
1741 sonymips mips-sony-*
1742 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1744 * REMOVED configurations and files
1746 SGI Irix-4.x mips-sgi-irix4 or iris4
1747 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1748 Z8000 simulator z8k-zilog-none or z8ksim
1749 Matsushita MN10200 w/simulator mn10200-*-*
1750 H8/500 simulator h8500-hitachi-hms or h8500hms
1751 HP/PA running BSD hppa*-*-bsd*
1752 HP/PA running OSF/1 hppa*-*-osf*
1753 HP/PA Pro target hppa*-*-pro*
1754 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1755 386BSD i[3456]86-*-bsd*
1756 Sequent family i[3456]86-sequent-sysv4*
1757 i[3456]86-sequent-sysv*
1758 i[3456]86-sequent-bsd*
1759 SPARC running LynxOS sparc-*-lynxos*
1760 SPARC running SunOS 4 sparc-*-sunos4*
1761 Tsqware Sparclet sparclet-*-*
1762 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1764 *** Changes in GDB 6.0:
1768 Support for debugging the Objective-C programming language has been
1769 integrated into GDB.
1771 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1773 DWARF 2's Call Frame Information makes available compiler generated
1774 information that more exactly describes the program's run-time stack.
1775 By using this information, GDB is able to provide more robust stack
1778 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1779 have been updated to use a new backtrace mechanism which includes
1780 DWARF 2 CFI support.
1784 GDB's remote protocol has been extended to include support for hosted
1785 file I/O (where the remote target uses GDB's file system). See GDB's
1786 remote protocol documentation for details.
1788 * All targets using the new architecture framework.
1790 All of GDB's targets have been updated to use the new internal
1791 architecture framework. The way is now open for future GDB releases
1792 to include cross-architecture native debugging support (i386 on amd64,
1795 * GNU/Linux's Thread Local Storage (TLS)
1797 GDB now includes support for for the GNU/Linux implementation of
1798 per-thread variables.
1800 * GNU/Linux's Native POSIX Thread Library (NPTL)
1802 GDB's thread code has been updated to work with either the new
1803 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1805 * Separate debug info.
1807 GDB, in conjunction with BINUTILS, now supports a mechanism for
1808 automatically loading debug information from a separate file. Instead
1809 of shipping full debug and non-debug versions of system libraries,
1810 system integrators can now instead ship just the stripped libraries
1811 and optional debug files.
1813 * DWARF 2 Location Expressions
1815 DWARF 2 Location Expressions allow the compiler to more completely
1816 describe the location of variables (even in optimized code) to the
1819 GDB now includes preliminary support for location expressions (support
1820 for DW_OP_piece is still missing).
1824 A number of long standing bugs that caused GDB to die while starting a
1825 Java application have been fixed. GDB's Java support is now
1826 considered "useable".
1828 * GNU/Linux support for fork, vfork, and exec.
1830 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1831 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1834 * GDB supports logging output to a file
1836 There are two new commands, "set logging" and "show logging", which can be
1837 used to capture GDB's output to a file.
1839 * The meaning of "detach" has changed for gdbserver
1841 The "detach" command will now resume the application, as documented. To
1842 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1845 * d10v, m68hc11 `regs' command deprecated
1847 The `info registers' command has been updated so that it displays the
1848 registers using a format identical to the old `regs' command.
1852 A new command, "maint set profile on/off", has been added. This command can
1853 be used to enable or disable profiling while running GDB, to profile a
1854 session or a set of commands. In addition there is a new configure switch,
1855 "--enable-profiling", which will cause GDB to be compiled with profiling
1856 data, for more informative profiling results.
1858 * Default MI syntax changed to "mi2".
1860 The default MI (machine interface) syntax, enabled by the command line
1861 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1862 "mi1", can be enabled by specifying the option "-i=mi1".
1864 Support for the original "mi0" syntax (included in GDB 5.0) has been
1867 Fix for gdb/192: removed extraneous space when displaying frame level.
1868 Fix for gdb/672: update changelist is now output in mi list format.
1869 Fix for gdb/702: a -var-assign that updates the value now shows up
1870 in a subsequent -var-update.
1872 * New native configurations.
1874 FreeBSD/amd64 x86_64-*-freebsd*
1876 * Multi-arched targets.
1878 HP/PA HPUX11 hppa*-*-hpux*
1879 Renesas M32R/D w/simulator m32r-*-elf*
1881 * OBSOLETE configurations and files
1883 Configurations that have been declared obsolete in this release have
1884 been commented out. Unless there is activity to revive these
1885 configurations, the next release of GDB will have their sources
1886 permanently REMOVED.
1888 Z8000 simulator z8k-zilog-none or z8ksim
1889 Matsushita MN10200 w/simulator mn10200-*-*
1890 H8/500 simulator h8500-hitachi-hms or h8500hms
1891 HP/PA running BSD hppa*-*-bsd*
1892 HP/PA running OSF/1 hppa*-*-osf*
1893 HP/PA Pro target hppa*-*-pro*
1894 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1895 Sequent family i[3456]86-sequent-sysv4*
1896 i[3456]86-sequent-sysv*
1897 i[3456]86-sequent-bsd*
1898 Tsqware Sparclet sparclet-*-*
1899 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1901 * REMOVED configurations and files
1904 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1905 IBM AIX PS/2 i[3456]86-*-aix
1906 i386 running Mach 3.0 i[3456]86-*-mach3*
1907 i386 running Mach i[3456]86-*-mach*
1908 i386 running OSF/1 i[3456]86-*osf1mk*
1909 HP/Apollo 68k Family m68*-apollo*-sysv*,
1911 m68*-hp-bsd*, m68*-hp-hpux*
1912 Argonaut Risc Chip (ARC) arc-*-*
1913 Mitsubishi D30V d30v-*-*
1914 Fujitsu FR30 fr30-*-elf*
1915 OS/9000 i[34]86-*-os9k
1916 I960 with MON960 i960-*-coff
1918 * MIPS $fp behavior changed
1920 The convenience variable $fp, for the MIPS, now consistently returns
1921 the address of the current frame's base. Previously, depending on the
1922 context, $fp could refer to either $sp or the current frame's base
1923 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1924 The GNU Source-Level Debugger''.
1926 *** Changes in GDB 5.3:
1928 * GNU/Linux shared library multi-threaded performance improved.
1930 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1931 `/proc', in preference to `ptrace' for memory reads. This may result
1932 in an improvement in the start-up time of multi-threaded, shared
1933 library applications when run under GDB. One GDB user writes: ``loads
1934 shared libs like mad''.
1936 * ``gdbserver'' now supports multi-threaded applications on some targets
1938 Support for debugging multi-threaded applications which use
1939 the GNU/Linux LinuxThreads package has been added for
1940 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1941 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1943 * GDB now supports C/C++ preprocessor macros.
1945 GDB now expands preprocessor macro invocations in C/C++ expressions,
1946 and provides various commands for showing macro definitions and how
1949 The new command `macro expand EXPRESSION' expands any macro
1950 invocations in expression, and shows the result.
1952 The new command `show macro MACRO-NAME' shows the definition of the
1953 macro named MACRO-NAME, and where it was defined.
1955 Most compilers don't include information about macros in the debugging
1956 information by default. In GCC 3.1, for example, you need to compile
1957 your program with the options `-gdwarf-2 -g3'. If the macro
1958 information is present in the executable, GDB will read it.
1960 * Multi-arched targets.
1962 DEC Alpha (partial) alpha*-*-*
1963 DEC VAX (partial) vax-*-*
1965 National Semiconductor NS32000 (partial) ns32k-*-*
1966 Motorola 68000 (partial) m68k-*-*
1967 Motorola MCORE mcore-*-*
1971 Fujitsu FRV architecture added by Red Hat frv*-*-*
1974 * New native configurations
1976 Alpha NetBSD alpha*-*-netbsd*
1977 SH NetBSD sh*-*-netbsdelf*
1978 MIPS NetBSD mips*-*-netbsd*
1979 UltraSPARC NetBSD sparc64-*-netbsd*
1981 * OBSOLETE configurations and files
1983 Configurations that have been declared obsolete in this release have
1984 been commented out. Unless there is activity to revive these
1985 configurations, the next release of GDB will have their sources
1986 permanently REMOVED.
1988 Mitsubishi D30V d30v-*-*
1989 OS/9000 i[34]86-*-os9k
1990 IBM AIX PS/2 i[3456]86-*-aix
1991 Fujitsu FR30 fr30-*-elf*
1992 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1993 Argonaut Risc Chip (ARC) arc-*-*
1994 i386 running Mach 3.0 i[3456]86-*-mach3*
1995 i386 running Mach i[3456]86-*-mach*
1996 i386 running OSF/1 i[3456]86-*osf1mk*
1997 HP/Apollo 68k Family m68*-apollo*-sysv*,
1999 m68*-hp-bsd*, m68*-hp-hpux*
2000 I960 with MON960 i960-*-coff
2002 * OBSOLETE languages
2004 CHILL, a Pascal like language used by telecommunications companies.
2006 * REMOVED configurations and files
2008 AMD 29k family via UDI a29k-amd-udi, udi29k
2009 A29K VxWorks a29k-*-vxworks
2010 AMD 29000 embedded, using EBMON a29k-none-none
2011 AMD 29000 embedded with COFF a29k-none-coff
2012 AMD 29000 embedded with a.out a29k-none-aout
2014 testsuite/gdb.hp/gdb.threads-hp/ directory
2016 * New command "set max-user-call-depth <nnn>"
2018 This command allows the user to limit the call depth of user-defined
2019 commands. The default is 1024.
2021 * Changes in FreeBSD/i386 native debugging.
2023 Support for the "generate-core-file" has been added.
2025 * New commands "dump", "append", and "restore".
2027 These commands allow data to be copied from target memory
2028 to a bfd-format or binary file (dump and append), and back
2029 from a file into memory (restore).
2031 * Improved "next/step" support on multi-processor Alpha Tru64.
2033 The previous single-step mechanism could cause unpredictable problems,
2034 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2035 of a software single-step mechanism prevents this.
2037 *** Changes in GDB 5.2.1:
2045 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2046 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2047 Fix, by Joel Brobecker imported from mainline.
2049 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2050 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2051 Fix, by Fred Fish, imported from mainline.
2053 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2054 Surprisingly enough, it works now.
2055 By Michal Ludvig, imported from mainline.
2057 i386 hardware watchpoint support:
2058 avoid misses on second run for some targets.
2059 By Pierre Muller, imported from mainline.
2061 *** Changes in GDB 5.2:
2063 * New command "set trust-readonly-sections on[off]".
2065 This command is a hint that tells gdb that read-only sections
2066 really are read-only (ie. that their contents will not change).
2067 In this mode, gdb will go to the object file rather than the
2068 target to read memory from read-only sections (such as ".text").
2069 This can be a significant performance improvement on some
2070 (notably embedded) targets.
2072 * New command "generate-core-file" (or "gcore").
2074 This new gdb command allows the user to drop a core file of the child
2075 process state at any time. So far it's been implemented only for
2076 GNU/Linux and Solaris, but should be relatively easily ported to other
2077 hosts. Argument is core file name (defaults to core.<pid>).
2079 * New command line option
2081 GDB now accepts --pid or -p followed by a process id.
2083 * Change in command line behavior -- corefiles vs. process ids.
2085 There is a subtle behavior in the way in which GDB handles
2086 command line arguments. The first non-flag argument is always
2087 a program to debug, but the second non-flag argument may either
2088 be a corefile or a process id. Previously, GDB would attempt to
2089 open the second argument as a corefile, and if that failed, would
2090 issue a superfluous error message and then attempt to attach it as
2091 a process. Now, if the second argument begins with a non-digit,
2092 it will be treated as a corefile. If it begins with a digit,
2093 GDB will attempt to attach it as a process, and if no such process
2094 is found, will then attempt to open it as a corefile.
2096 * Changes in ARM configurations.
2098 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2099 configuration is fully multi-arch.
2101 * New native configurations
2103 ARM NetBSD arm*-*-netbsd*
2104 x86 OpenBSD i[3456]86-*-openbsd*
2105 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2106 Sparc64 running FreeBSD sparc64-*-freebsd*
2110 Sanyo XStormy16 xstormy16-elf
2112 * OBSOLETE configurations and files
2114 Configurations that have been declared obsolete in this release have
2115 been commented out. Unless there is activity to revive these
2116 configurations, the next release of GDB will have their sources
2117 permanently REMOVED.
2119 AMD 29k family via UDI a29k-amd-udi, udi29k
2120 A29K VxWorks a29k-*-vxworks
2121 AMD 29000 embedded, using EBMON a29k-none-none
2122 AMD 29000 embedded with COFF a29k-none-coff
2123 AMD 29000 embedded with a.out a29k-none-aout
2125 testsuite/gdb.hp/gdb.threads-hp/ directory
2127 * REMOVED configurations and files
2129 TI TMS320C80 tic80-*-*
2131 PowerPC Solaris powerpcle-*-solaris*
2132 PowerPC Windows NT powerpcle-*-cygwin32
2133 PowerPC Netware powerpc-*-netware*
2134 Harris/CXUX m88k m88*-harris-cxux*
2135 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2136 ns32k-utek-sysv* ns32k-utek-*
2137 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2138 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2139 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2140 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2141 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2143 * Changes to command line processing
2145 The new `--args' feature can be used to specify command-line arguments
2146 for the inferior from gdb's command line.
2148 * Changes to key bindings
2150 There is a new `operate-and-get-next' function bound to `C-o'.
2152 *** Changes in GDB 5.1.1
2154 Fix compile problem on DJGPP.
2156 Fix a problem with floating-point registers on the i386 being
2159 Fix to stop GDB crashing on .debug_str debug info.
2161 Numerous documentation fixes.
2163 Numerous testsuite fixes.
2165 *** Changes in GDB 5.1:
2167 * New native configurations
2169 Alpha FreeBSD alpha*-*-freebsd*
2170 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2171 MIPS GNU/Linux mips*-*-linux*
2172 MIPS SGI Irix 6.x mips*-sgi-irix6*
2173 ia64 AIX ia64-*-aix*
2174 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2178 Motorola 68HC11 and 68HC12 m68hc11-elf
2180 UltraSparc running GNU/Linux sparc64-*-linux*
2182 * OBSOLETE configurations and files
2184 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2185 Harris/CXUX m88k m88*-harris-cxux*
2186 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2187 ns32k-utek-sysv* ns32k-utek-*
2188 TI TMS320C80 tic80-*-*
2190 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2191 PowerPC Solaris powerpcle-*-solaris*
2192 PowerPC Windows NT powerpcle-*-cygwin32
2193 PowerPC Netware powerpc-*-netware*
2194 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2195 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2196 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2197 Apple Macintosh (MPW) host N/A
2199 stuff.c (Program to stuff files into a specially prepared space in kdb)
2200 kdb-start.c (Main loop for the standalone kernel debugger)
2202 Configurations that have been declared obsolete in this release have
2203 been commented out. Unless there is activity to revive these
2204 configurations, the next release of GDB will have their sources
2205 permanently REMOVED.
2207 * REMOVED configurations and files
2209 Altos 3068 m68*-altos-*
2210 Convex c1-*-*, c2-*-*
2212 ARM RISCix arm-*-* (as host)
2216 * GDB has been converted to ISO C.
2218 GDB's source code has been converted to ISO C. In particular, the
2219 sources are fully protoized, and rely on standard headers being
2224 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2226 * The MI enabled by default.
2228 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2229 revised and enabled by default. Packages which use GDB as a debugging
2230 engine behind a UI or another front end are encouraged to switch to
2231 using the GDB/MI interface, instead of the old annotations interface
2232 which is now deprecated.
2234 * Support for debugging Pascal programs.
2236 GDB now includes support for debugging Pascal programs. The following
2237 main features are supported:
2239 - Pascal-specific data types such as sets;
2241 - automatic recognition of Pascal sources based on file-name
2244 - Pascal-style display of data types, variables, and functions;
2246 - a Pascal expression parser.
2248 However, some important features are not yet supported.
2250 - Pascal string operations are not supported at all;
2252 - there are some problems with boolean types;
2254 - Pascal type hexadecimal constants are not supported
2255 because they conflict with the internal variables format;
2257 - support for Pascal objects and classes is not full yet;
2259 - unlike Pascal, GDB is case-sensitive for symbol names.
2261 * Changes in completion.
2263 Commands such as `shell', `run' and `set args', which pass arguments
2264 to inferior programs, now complete on file names, similar to what
2265 users expect at the shell prompt.
2267 Commands which accept locations, such as `disassemble', `print',
2268 `breakpoint', `until', etc. now complete on filenames as well as
2269 program symbols. Thus, if you type "break foob TAB", and the source
2270 files linked into the programs include `foobar.c', that file name will
2271 be one of the candidates for completion. However, file names are not
2272 considered for completion after you typed a colon that delimits a file
2273 name from a name of a function in that file, as in "break foo.c:bar".
2275 `set demangle-style' completes on available demangling styles.
2277 * New platform-independent commands:
2279 It is now possible to define a post-hook for a command as well as a
2280 hook that runs before the command. For more details, see the
2281 documentation of `hookpost' in the GDB manual.
2283 * Changes in GNU/Linux native debugging.
2285 Support for debugging multi-threaded programs has been completely
2286 revised for all platforms except m68k and sparc. You can now debug as
2287 many threads as your system allows you to have.
2289 Attach/detach is supported for multi-threaded programs.
2291 Support for SSE registers was added for x86. This doesn't work for
2292 multi-threaded programs though.
2294 * Changes in MIPS configurations.
2296 Multi-arch support is enabled for all MIPS configurations.
2298 GDB can now be built as native debugger on SGI Irix 6.x systems for
2299 debugging n32 executables. (Debugging 64-bit executables is not yet
2302 * Unified support for hardware watchpoints in all x86 configurations.
2304 Most (if not all) native x86 configurations support hardware-assisted
2305 breakpoints and watchpoints in a unified manner. This support
2306 implements debug register sharing between watchpoints, which allows to
2307 put a virtually infinite number of watchpoints on the same address,
2308 and also supports watching regions up to 16 bytes with several debug
2311 The new maintenance command `maintenance show-debug-regs' toggles
2312 debugging print-outs in functions that insert, remove, and test
2313 watchpoints and hardware breakpoints.
2315 * Changes in the DJGPP native configuration.
2317 New command ``info dos sysinfo'' displays assorted information about
2318 the CPU, OS, memory, and DPMI server.
2320 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2321 display information about segment descriptors stored in GDT, LDT, and
2324 New commands ``info dos pde'' and ``info dos pte'' display entries
2325 from Page Directory and Page Tables (for now works with CWSDPMI only).
2326 New command ``info dos address-pte'' displays the Page Table entry for
2327 a given linear address.
2329 GDB can now pass command lines longer than 126 characters to the
2330 program being debugged (requires an update to the libdbg.a library
2331 which is part of the DJGPP development kit).
2333 DWARF2 debug info is now supported.
2335 It is now possible to `step' and `next' through calls to `longjmp'.
2337 * Changes in documentation.
2339 All GDB documentation was converted to GFDL, the GNU Free
2340 Documentation License.
2342 Tracepoints-related commands are now fully documented in the GDB
2345 TUI, the Text-mode User Interface, is now documented in the manual.
2347 Tracepoints-related commands are now fully documented in the GDB
2350 The "GDB Internals" manual now has an index. It also includes
2351 documentation of `ui_out' functions, GDB coding standards, x86
2352 hardware watchpoints, and memory region attributes.
2354 * GDB's version number moved to ``version.in''
2356 The Makefile variable VERSION has been replaced by the file
2357 ``version.in''. People creating GDB distributions should update the
2358 contents of this file.
2362 GUD support is now a standard part of the EMACS distribution.
2364 *** Changes in GDB 5.0:
2366 * Improved support for debugging FP programs on x86 targets
2368 Unified and much-improved support for debugging floating-point
2369 programs on all x86 targets. In particular, ``info float'' now
2370 displays the FP registers in the same format on all x86 targets, with
2371 greater level of detail.
2373 * Improvements and bugfixes in hardware-assisted watchpoints
2375 It is now possible to watch array elements, struct members, and
2376 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2377 on x86 targets no longer erroneously trigger when the address is
2380 * Improvements in the native DJGPP version of GDB
2382 The distribution now includes all the scripts and auxiliary files
2383 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2384 machines ``out of the box''.
2386 The DJGPP version can now debug programs that use signals. It is
2387 possible to catch signals that happened in the debuggee, deliver
2388 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2389 would kill the program being debugged.) Programs that hook hardware
2390 interrupts (keyboard, timer, etc.) can also be debugged.
2392 It is now possible to debug DJGPP programs that redirect their
2393 standard handles or switch them to raw (as opposed to cooked) mode, or
2394 even close them. The command ``run < foo > bar'' works as expected,
2395 and ``info terminal'' reports useful information about the debuggee's
2396 terminal, including raw/cooked mode, redirection, etc.
2398 The DJGPP version now uses termios functions for console I/O, which
2399 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2402 DOS-style file names with drive letters are now fully supported by
2405 It is now possible to debug DJGPP programs that switch their working
2406 directory. It is also possible to rerun the debuggee any number of
2407 times without restarting GDB; thus, you can use the same setup,
2408 breakpoints, etc. for many debugging sessions.
2410 * New native configurations
2412 ARM GNU/Linux arm*-*-linux*
2413 PowerPC GNU/Linux powerpc-*-linux*
2417 Motorola MCore mcore-*-*
2418 x86 VxWorks i[3456]86-*-vxworks*
2419 PowerPC VxWorks powerpc-*-vxworks*
2420 TI TMS320C80 tic80-*-*
2422 * OBSOLETE configurations
2424 Altos 3068 m68*-altos-*
2425 Convex c1-*-*, c2-*-*
2427 ARM RISCix arm-*-* (as host)
2430 Configurations that have been declared obsolete will be commented out,
2431 but the code will be left in place. If there is no activity to revive
2432 these configurations before the next release of GDB, the sources will
2433 be permanently REMOVED.
2435 * Gould support removed
2437 Support for the Gould PowerNode and NP1 has been removed.
2439 * New features for SVR4
2441 On SVR4 native platforms (such as Solaris), if you attach to a process
2442 without first loading a symbol file, GDB will now attempt to locate and
2443 load symbols from the running process's executable file.
2445 * Many C++ enhancements
2447 C++ support has been greatly improved. Overload resolution now works properly
2448 in almost all cases. RTTI support is on the way.
2450 * Remote targets can connect to a sub-program
2452 A popen(3) style serial-device has been added. This device starts a
2453 sub-process (such as a stand-alone simulator) and then communicates
2454 with that. The sub-program to run is specified using the syntax
2455 ``|<program> <args>'' vis:
2457 (gdb) set remotedebug 1
2458 (gdb) target extended-remote |mn10300-elf-sim program-args
2460 * MIPS 64 remote protocol
2462 A long standing bug in the mips64 remote protocol where by GDB
2463 expected certain 32 bit registers (ex SR) to be transfered as 32
2464 instead of 64 bits has been fixed.
2466 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2467 added to provide backward compatibility with older versions of GDB.
2469 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2471 The command ``set remotebinarydownload'' command has been replaced by
2472 ``set remote X-packet''. Other commands in ``set remote'' family
2473 include ``set remote P-packet''.
2475 * Breakpoint commands accept ranges.
2477 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2478 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2479 ``tracepoint passcount'' also accepts a range of tracepoints.
2481 * ``apropos'' command added.
2483 The ``apropos'' command searches through command names and
2484 documentation strings, printing out matches, making it much easier to
2485 try to find a command that does what you are looking for.
2489 A new machine oriented interface (MI) has been added to GDB. This
2490 interface is designed for debug environments running GDB as a separate
2491 process. This is part of the long term libGDB project. See the
2492 "GDB/MI" chapter of the GDB manual for further information. It can be
2493 enabled by configuring with:
2495 .../configure --enable-gdbmi
2497 *** Changes in GDB-4.18:
2499 * New native configurations
2501 HP-UX 10.20 hppa*-*-hpux10.20
2502 HP-UX 11.x hppa*-*-hpux11.0*
2503 M68K GNU/Linux m68*-*-linux*
2507 Fujitsu FR30 fr30-*-elf*
2508 Intel StrongARM strongarm-*-*
2509 Mitsubishi D30V d30v-*-*
2511 * OBSOLETE configurations
2513 Gould PowerNode, NP1 np1-*-*, pn-*-*
2515 Configurations that have been declared obsolete will be commented out,
2516 but the code will be left in place. If there is no activity to revive
2517 these configurations before the next release of GDB, the sources will
2518 be permanently REMOVED.
2522 As a compatibility experiment, GDB's source files buildsym.h and
2523 buildsym.c have been converted to pure standard C, no longer
2524 containing any K&R compatibility code. We believe that all systems in
2525 use today either come with a standard C compiler, or have a GCC port
2526 available. If this is not true, please report the affected
2527 configuration to bug-gdb@gnu.org immediately. See the README file for
2528 information about getting a standard C compiler if you don't have one
2533 GDB now uses readline 2.2.
2535 * set extension-language
2537 You can now control the mapping between filename extensions and source
2538 languages by using the `set extension-language' command. For instance,
2539 you can ask GDB to treat .c files as C++ by saying
2540 set extension-language .c c++
2541 The command `info extensions' lists all of the recognized extensions
2542 and their associated languages.
2544 * Setting processor type for PowerPC and RS/6000
2546 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2547 you can use the `set processor' command to specify what variant of the
2548 PowerPC family you are debugging. The command
2552 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2553 following PowerPC and RS6000 variants:
2555 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2556 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2558 403GC IBM PowerPC 403GC
2559 505 Motorola PowerPC 505
2560 860 Motorola PowerPC 860 or 850
2561 601 Motorola PowerPC 601
2562 602 Motorola PowerPC 602
2563 603 Motorola/IBM PowerPC 603 or 603e
2564 604 Motorola PowerPC 604 or 604e
2565 750 Motorola/IBM PowerPC 750 or 750
2567 At the moment, this command just tells GDB what to name the
2568 special-purpose processor registers. Since almost all the affected
2569 registers are inaccessible to user-level programs, this command is
2570 only useful for remote debugging in its present form.
2574 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2575 more extensive support for HP-UX. Added features include shared
2576 library support, kernel threads and hardware watchpoints for 11.00,
2577 support for HP's ANSI C and C++ compilers, and a compatibility mode
2578 for xdb and dbx commands.
2582 HP's donation includes the new concept of catchpoints, which is a
2583 generalization of the old catch command. On HP-UX, it is now possible
2584 to catch exec, fork, and vfork, as well as library loading.
2586 This means that the existing catch command has changed; its first
2587 argument now specifies the type of catch to be set up. See the
2588 output of "help catch" for a list of catchpoint types.
2590 * Debugging across forks
2592 On HP-UX, you can choose which process to debug when a fork() happens
2597 HP has donated a curses-based terminal user interface (TUI). To get
2598 it, build with --enable-tui. Although this can be enabled for any
2599 configuration, at present it only works for native HP debugging.
2601 * GDB remote protocol additions
2603 A new protocol packet 'X' that writes binary data is now available.
2604 Default behavior is to try 'X', then drop back to 'M' if the stub
2605 fails to respond. The settable variable `remotebinarydownload'
2606 allows explicit control over the use of 'X'.
2608 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2609 full 64-bit address. The command
2611 set remoteaddresssize 32
2613 can be used to revert to the old behaviour. For existing remote stubs
2614 the change should not be noticed, as the additional address information
2617 In order to assist in debugging stubs, you may use the maintenance
2618 command `packet' to send any text string to the stub. For instance,
2620 maint packet heythere
2622 sends the packet "$heythere#<checksum>". Note that it is very easy to
2623 disrupt a debugging session by sending the wrong packet at the wrong
2626 The compare-sections command allows you to compare section data on the
2627 target to what is in the executable file without uploading or
2628 downloading, by comparing CRC checksums.
2630 * Tracing can collect general expressions
2632 You may now collect general expressions at tracepoints. This requires
2633 further additions to the target-side stub; see tracepoint.c and
2634 doc/agentexpr.texi for further details.
2636 * mask-address variable for Mips
2638 For Mips targets, you may control the zeroing of the upper 32 bits of
2639 a 64-bit address by entering `set mask-address on'. This is mainly
2640 of interest to users of embedded R4xxx and R5xxx processors.
2642 * Higher serial baud rates
2644 GDB's serial code now allows you to specify baud rates 57600, 115200,
2645 230400, and 460800 baud. (Note that your host system may not be able
2646 to achieve all of these rates.)
2650 The i960 configuration now includes an initial implementation of a
2651 builtin simulator, contributed by Jim Wilson.
2654 *** Changes in GDB-4.17:
2656 * New native configurations
2658 Alpha GNU/Linux alpha*-*-linux*
2659 Unixware 2.x i[3456]86-unixware2*
2660 Irix 6.x mips*-sgi-irix6*
2661 PowerPC GNU/Linux powerpc-*-linux*
2662 PowerPC Solaris powerpcle-*-solaris*
2663 Sparc GNU/Linux sparc-*-linux*
2664 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2668 Argonaut Risc Chip (ARC) arc-*-*
2669 Hitachi H8/300S h8300*-*-*
2670 Matsushita MN10200 w/simulator mn10200-*-*
2671 Matsushita MN10300 w/simulator mn10300-*-*
2672 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2673 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2674 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2675 Mitsubishi D10V w/simulator d10v-*-*
2676 Mitsubishi M32R/D w/simulator m32r-*-elf*
2677 Tsqware Sparclet sparclet-*-*
2678 NEC V850 w/simulator v850-*-*
2680 * New debugging protocols
2682 ARM with RDI protocol arm*-*-*
2683 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2684 DDB and LSI variants of PMON protocol mips*-*-*
2685 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2686 PowerPC with SDS protocol powerpc{,le}-*-eabi
2687 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2691 All configurations can now understand and use the DWARF 2 debugging
2692 format. The choice is automatic, if the symbol file contains DWARF 2
2697 GDB now includes basic Java language support. This support is
2698 only useful with Java compilers that produce native machine code.
2700 * solib-absolute-prefix and solib-search-path
2702 For SunOS and SVR4 shared libraries, you may now set the prefix for
2703 loading absolute shared library symbol files, and the search path for
2704 locating non-absolute shared library symbol files.
2706 * Live range splitting
2708 GDB can now effectively debug code for which GCC has performed live
2709 range splitting as part of its optimization. See gdb/doc/LRS for
2710 more details on the expected format of the stabs information.
2714 GDB's support for the GNU Hurd, including thread debugging, has been
2715 updated to work with current versions of the Hurd.
2719 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2720 instruction set. ARM GDB automatically detects when Thumb
2721 instructions are in use, and adjusts disassembly and backtracing
2726 GDB's MIPS target configurations now handle the MIP16 16-bit
2731 GDB now includes support for overlays; if an executable has been
2732 linked such that multiple sections are based at the same address, GDB
2733 will decide which section to use for symbolic info. You can choose to
2734 control the decision manually, using overlay commands, or implement
2735 additional target-side support and use "overlay load-target" to bring
2736 in the overlay mapping. Do "help overlay" for more detail.
2740 The command "info symbol <address>" displays information about
2741 the symbol at the specified address.
2745 The standard remote protocol now includes an extension that allows
2746 asynchronous collection and display of trace data. This requires
2747 extensive support in the target-side debugging stub. Tracing mode
2748 includes a new interaction mode in GDB and new commands: see the
2749 file tracepoint.c for more details.
2753 Configurations for embedded MIPS now include a simulator contributed
2754 by Cygnus Solutions. The simulator supports the instruction sets
2755 of most MIPS variants.
2759 Sparc configurations may now include the ERC32 simulator contributed
2760 by the European Space Agency. The simulator is not built into
2761 Sparc targets by default; configure with --enable-sim to include it.
2765 For target configurations that may include multiple variants of a
2766 basic architecture (such as MIPS and SH), you may now set the
2767 architecture explicitly. "set arch" sets, "info arch" lists
2768 the possible architectures.
2770 *** Changes in GDB-4.16:
2772 * New native configurations
2774 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2775 M68K NetBSD m68k-*-netbsd*
2776 PowerPC AIX 4.x powerpc-*-aix*
2777 PowerPC MacOS powerpc-*-macos*
2778 PowerPC Windows NT powerpcle-*-cygwin32
2779 RS/6000 AIX 4.x rs6000-*-aix4*
2783 ARM with RDP protocol arm-*-*
2784 I960 with MON960 i960-*-coff
2785 MIPS VxWorks mips*-*-vxworks*
2786 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2787 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2789 Matra Sparclet sparclet-*-*
2793 The powerpc-eabi configuration now includes the PSIM simulator,
2794 contributed by Andrew Cagney, with assistance from Mike Meissner.
2795 PSIM is a very elaborate model of the PowerPC, including not only
2796 basic instruction set execution, but also details of execution unit
2797 performance and I/O hardware. See sim/ppc/README for more details.
2801 GDB now works with Solaris 2.5.
2803 * Windows 95/NT native
2805 GDB will now work as a native debugger on Windows 95 and Windows NT.
2806 To build it from source, you must use the "gnu-win32" environment,
2807 which uses a DLL to emulate enough of Unix to run the GNU tools.
2808 Further information, binaries, and sources are available at
2809 ftp.cygnus.com, under pub/gnu-win32.
2811 * dont-repeat command
2813 If a user-defined command includes the command `dont-repeat', then the
2814 command will not be repeated if the user just types return. This is
2815 useful if the command is time-consuming to run, so that accidental
2816 extra keystrokes don't run the same command many times.
2818 * Send break instead of ^C
2820 The standard remote protocol now includes an option to send a break
2821 rather than a ^C to the target in order to interrupt it. By default,
2822 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2824 * Remote protocol timeout
2826 The standard remote protocol includes a new variable `remotetimeout'
2827 that allows you to set the number of seconds before GDB gives up trying
2828 to read from the target. The default value is 2.
2830 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2832 By default GDB will automatically keep track of objects as they are
2833 loaded and unloaded by the dynamic linker. By using the command `set
2834 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2835 when shared library events occur, thus allowing you to set breakpoints
2836 in shared libraries which are explicitly loaded by the inferior.
2838 Note this feature does not work on hpux8. On hpux9 you must link
2839 /usr/lib/end.o into your program. This feature should work
2840 automatically on hpux10.
2842 * Irix 5.x hardware watchpoint support
2844 Irix 5 configurations now support the use of hardware watchpoints.
2846 * Mips protocol "SYN garbage limit"
2848 When debugging a Mips target using the `target mips' protocol, you
2849 may set the number of characters that GDB will ignore by setting
2850 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2851 every character. The default value is 1050.
2853 * Recording and replaying remote debug sessions
2855 If you set `remotelogfile' to the name of a file, gdb will write to it
2856 a recording of a remote debug session. This recording may then be
2857 replayed back to gdb using "gdbreplay". See gdbserver/README for
2858 details. This is useful when you have a problem with GDB while doing
2859 remote debugging; you can make a recording of the session and send it
2860 to someone else, who can then recreate the problem.
2862 * Speedups for remote debugging
2864 GDB includes speedups for downloading and stepping MIPS systems using
2865 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2866 and more efficient S-record downloading.
2868 * Memory use reductions and statistics collection
2870 GDB now uses less memory and reports statistics about memory usage.
2871 Try the `maint print statistics' command, for example.
2873 *** Changes in GDB-4.15:
2875 * Psymtabs for XCOFF
2877 The symbol reader for AIX GDB now uses partial symbol tables. This
2878 can greatly improve startup time, especially for large executables.
2880 * Remote targets use caching
2882 Remote targets now use a data cache to speed up communication with the
2883 remote side. The data cache could lead to incorrect results because
2884 it doesn't know about volatile variables, thus making it impossible to
2885 debug targets which use memory mapped I/O devices. `set remotecache
2886 off' turns the the data cache off.
2888 * Remote targets may have threads
2890 The standard remote protocol now includes support for multiple threads
2891 in the target system, using new protocol commands 'H' and 'T'. See
2892 gdb/remote.c for details.
2896 If GDB is configured with `--enable-netrom', then it will include
2897 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2898 acts as though it is a bank of ROM on the target board, but you can
2899 write into it over the network. GDB's support consists only of
2900 support for fast loading into the emulated ROM; to debug, you must use
2901 another protocol, such as standard remote protocol. The usual
2902 sequence is something like
2904 target nrom <netrom-hostname>
2906 target remote <netrom-hostname>:1235
2910 GDB now includes support for the Apple Macintosh, as a host only. It
2911 may be run as either an MPW tool or as a standalone application, and
2912 it can debug through the serial port. All the usual GDB commands are
2913 available, but to the target command, you must supply "serial" as the
2914 device type instead of "/dev/ttyXX". See mpw-README in the main
2915 directory for more information on how to build. The MPW configuration
2916 scripts */mpw-config.in support only a few targets, and only the
2917 mips-idt-ecoff target has been tested.
2921 GDB configuration now uses autoconf. This is not user-visible,
2922 but does simplify configuration and building.
2926 GDB now supports hpux10.
2928 *** Changes in GDB-4.14:
2930 * New native configurations
2932 x86 FreeBSD i[345]86-*-freebsd
2933 x86 NetBSD i[345]86-*-netbsd
2934 NS32k NetBSD ns32k-*-netbsd
2935 Sparc NetBSD sparc-*-netbsd
2939 A29K VxWorks a29k-*-vxworks
2940 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2941 CPU32 EST-300 emulator m68*-*-est*
2942 PowerPC ELF powerpc-*-elf
2945 * Alpha OSF/1 support for procfs
2947 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2948 possible to attach to running processes. As the mounting of the /proc
2949 filesystem is optional on the Alpha, GDB automatically determines
2950 the availability of /proc during startup. This can lead to problems
2951 if /proc is unmounted after GDB has been started.
2953 * Arguments to user-defined commands
2955 User commands may accept up to 10 arguments separated by whitespace.
2956 Arguments are accessed within the user command via $arg0..$arg9. A
2959 print $arg0 + $arg1 + $arg2
2961 To execute the command use:
2964 Defines the command "adder" which prints the sum of its three arguments.
2965 Note the arguments are text substitutions, so they may reference variables,
2966 use complex expressions, or even perform inferior function calls.
2968 * New `if' and `while' commands
2970 This makes it possible to write more sophisticated user-defined
2971 commands. Both commands take a single argument, which is the
2972 expression to evaluate, and must be followed by the commands to
2973 execute, one per line, if the expression is nonzero, the list being
2974 terminated by the word `end'. The `if' command list may include an
2975 `else' word, which causes the following commands to be executed only
2976 if the expression is zero.
2978 * Fortran source language mode
2980 GDB now includes partial support for Fortran 77. It will recognize
2981 Fortran programs and can evaluate a subset of Fortran expressions, but
2982 variables and functions may not be handled correctly. GDB will work
2983 with G77, but does not yet know much about symbols emitted by other
2986 * Better HPUX support
2988 Most debugging facilities now work on dynamic executables for HPPAs
2989 running hpux9 or later. You can attach to running dynamically linked
2990 processes, but by default the dynamic libraries will be read-only, so
2991 for instance you won't be able to put breakpoints in them. To change
2992 that behavior do the following before running the program:
2998 This will cause the libraries to be mapped private and read-write.
2999 To revert to the normal behavior, do this:
3005 You cannot set breakpoints or examine data in the library until after
3006 the library is loaded if the function/data symbols do not have
3009 GDB can now also read debug symbols produced by the HP C compiler on
3010 HPPAs (sorry, no C++, Fortran or 68k support).
3012 * Target byte order now dynamically selectable
3014 You can choose which byte order to use with a target system, via the
3015 commands "set endian big" and "set endian little", and you can see the
3016 current setting by using "show endian". You can also give the command
3017 "set endian auto", in which case GDB will use the byte order
3018 associated with the executable. Currently, only embedded MIPS
3019 configurations support dynamic selection of target byte order.
3021 * New DOS host serial code
3023 This version uses DPMI interrupts to handle buffered I/O, so you
3024 no longer need to run asynctsr when debugging boards connected to
3027 *** Changes in GDB-4.13:
3029 * New "complete" command
3031 This lists all the possible completions for the rest of the line, if it
3032 were to be given as a command itself. This is intended for use by emacs.
3034 * Trailing space optional in prompt
3036 "set prompt" no longer adds a space for you after the prompt you set. This
3037 allows you to set a prompt which ends in a space or one that does not.
3039 * Breakpoint hit counts
3041 "info break" now displays a count of the number of times the breakpoint
3042 has been hit. This is especially useful in conjunction with "ignore"; you
3043 can ignore a large number of breakpoint hits, look at the breakpoint info
3044 to see how many times the breakpoint was hit, then run again, ignoring one
3045 less than that number, and this will get you quickly to the last hit of
3048 * Ability to stop printing at NULL character
3050 "set print null-stop" will cause GDB to stop printing the characters of
3051 an array when the first NULL is encountered. This is useful when large
3052 arrays actually contain only short strings.
3054 * Shared library breakpoints
3056 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3057 breakpoints in shared libraries before the executable is run.
3059 * Hardware watchpoints
3061 There is a new hardware breakpoint for the watch command for sparclite
3062 targets. See gdb/sparclite/hw_breakpoint.note.
3064 Hardware watchpoints are also now supported under GNU/Linux.
3068 Annotations have been added. These are for use with graphical interfaces,
3069 and are still experimental. Currently only gdba.el uses these.
3071 * Improved Irix 5 support
3073 GDB now works properly with Irix 5.2.
3075 * Improved HPPA support
3077 GDB now works properly with the latest GCC and GAS.
3079 * New native configurations
3081 Sequent PTX4 i[34]86-sequent-ptx4
3082 HPPA running OSF/1 hppa*-*-osf*
3083 Atari TT running SVR4 m68*-*-sysv4*
3084 RS/6000 LynxOS rs6000-*-lynxos*
3088 OS/9000 i[34]86-*-os9k
3089 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3092 * Hitachi SH7000 and E7000-PC ICE support
3094 There is now support for communicating with the Hitachi E7000-PC ICE.
3095 This is available automatically when GDB is configured for the SH.
3099 As usual, a variety of small fixes and improvements, both generic
3100 and configuration-specific. See the ChangeLog for more detail.
3102 *** Changes in GDB-4.12:
3104 * Irix 5 is now supported
3108 GDB-4.12 on the HPPA has a number of changes which make it unable
3109 to debug the output from the currently released versions of GCC and
3110 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3111 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3112 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3115 *** Changes in GDB-4.11:
3117 * User visible changes:
3121 The "set remotedebug" option is now consistent between the mips remote
3122 target, remote targets using the gdb-specific protocol, UDI (AMD's
3123 debug protocol for the 29k) and the 88k bug monitor. It is now an
3124 integer specifying a debug level (normally 0 or 1, but 2 means more
3125 debugging info for the mips target).
3127 * DEC Alpha native support
3129 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3130 debug info, but GDB works fairly well with the DEC compiler and should
3131 work with a future GCC release. See the README file for a few
3132 Alpha-specific notes.
3134 * Preliminary thread implementation
3136 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3138 * LynxOS native and target support for 386
3140 This release has been hosted on LynxOS 2.2, and also can be configured
3141 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3144 * Improvements in C++ mangling/demangling.
3146 This release has much better g++ debugging, specifically in name
3147 mangling/demangling, virtual function calls, print virtual table,
3148 call methods, ...etc.
3150 *** Changes in GDB-4.10:
3152 * User visible changes:
3154 Remote debugging using the GDB-specific (`target remote') protocol now
3155 supports the `load' command. This is only useful if you have some
3156 other way of getting the stub to the target system, and you can put it
3157 somewhere in memory where it won't get clobbered by the download.
3159 Filename completion now works.
3161 When run under emacs mode, the "info line" command now causes the
3162 arrow to point to the line specified. Also, "info line" prints
3163 addresses in symbolic form (as well as hex).
3165 All vxworks based targets now support a user settable option, called
3166 vxworks-timeout. This option represents the number of seconds gdb
3167 should wait for responses to rpc's. You might want to use this if
3168 your vxworks target is, perhaps, a slow software simulator or happens
3169 to be on the far side of a thin network line.
3173 This release contains support for using a DEC alpha as a GDB host for
3174 cross debugging. Native alpha debugging is not supported yet.
3177 *** Changes in GDB-4.9:
3181 This is the first GDB release which is accompanied by a matching testsuite.
3182 The testsuite requires installation of dejagnu, which should be available
3183 via ftp from most sites that carry GNU software.
3187 'Cfront' style demangling has had its name changed to 'ARM' style, to
3188 emphasize that it was written from the specifications in the C++ Annotated
3189 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3190 disclaimers, it still generated too much confusion with users attempting to
3191 use gdb with AT&T cfront.
3195 GDB now uses a standard remote interface to a simulator library.
3196 So far, the library contains simulators for the Zilog Z8001/2, the
3197 Hitachi H8/300, H8/500 and Super-H.
3199 * New targets supported
3201 H8/300 simulator h8300-hitachi-hms or h8300hms
3202 H8/500 simulator h8500-hitachi-hms or h8500hms
3203 SH simulator sh-hitachi-hms or sh
3204 Z8000 simulator z8k-zilog-none or z8ksim
3205 IDT MIPS board over serial line mips-idt-ecoff
3207 Cross-debugging to GO32 targets is supported. It requires a custom
3208 version of the i386-stub.c module which is integrated with the
3209 GO32 memory extender.
3211 * New remote protocols
3213 MIPS remote debugging protocol.
3215 * New source languages supported
3217 This version includes preliminary support for Chill, a Pascal like language
3218 used by telecommunications companies. Chill support is also being integrated
3219 into the GNU compiler, but we don't know when it will be publically available.
3222 *** Changes in GDB-4.8:
3224 * HP Precision Architecture supported
3226 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3227 version of this support was available as a set of patches from the
3228 University of Utah. GDB does not support debugging of programs
3229 compiled with the HP compiler, because HP will not document their file
3230 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3231 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3233 Many problems in the preliminary version have been fixed.
3235 * Faster and better demangling
3237 We have improved template demangling and fixed numerous bugs in the GNU style
3238 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3239 character types (wchar_t) are now supported. Demangling of each symbol is now
3240 only done once, and is cached when the symbol table for a file is read in.
3241 This results in a small increase in memory usage for C programs, a moderate
3242 increase in memory usage for C++ programs, and a fantastic speedup in
3245 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3246 from the specifications in the Annotated Reference Manual, which AT&T's
3247 compiler does not actually implement.
3249 * G++ multiple inheritance compiler problem
3251 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3252 inheritance lattices was reworked to properly discover ambiguities. We
3253 recently found an example which causes this new algorithm to fail in a
3254 very subtle way, producing bad debug information for those classes.
3255 The file 'gcc.patch' (in this directory) can be applied to gcc to
3256 circumvent the problem. A future GCC release will contain a complete
3259 The previous G++ debug info problem (mentioned below for the gdb-4.7
3260 release) is fixed in gcc version 2.3.2.
3262 * Improved configure script
3264 The `configure' script will now attempt to guess your system type if
3265 you don't supply a host system type. The old scheme of supplying a
3266 host system triplet is preferable over using this. All the magic is
3267 done in the new `config.guess' script. Examine it for details.
3269 We have also brought our configure script much more in line with the FSF's
3270 version. It now supports the --with-xxx options. In particular,
3271 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3272 The resulting GDB will not be able to read arbitrary object file formats --
3273 only the format ``expected'' to be used on the configured target system.
3274 We hope to make this the default in a future release.
3276 * Documentation improvements
3278 There's new internal documentation on how to modify GDB, and how to
3279 produce clean changes to the code. We implore people to read it
3280 before submitting changes.
3282 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3283 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3284 `info' files are also provided. To build `info' files from scratch,
3285 you will need the latest `makeinfo' release, which will be available in
3286 a future texinfo-X.Y release.
3288 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3289 We're not sure exactly which versions have this problem, but it has
3290 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3291 or better. If that isn't possible, there is a patch in
3292 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3293 around this problem.
3297 GDB now supports array constants that can be used in expressions typed in by
3298 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3299 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3302 The new directory `gdb/sparclite' contains a program that demonstrates
3303 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3305 * New native hosts supported
3307 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3308 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3310 * New targets supported
3312 AMD 29k family via UDI a29k-amd-udi or udi29k
3314 * New file formats supported
3316 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3317 HPUX core files, and SCO 3.2v2 core files.
3321 Attaching to processes now works again; thanks for the many bug reports.
3323 We have also stomped on a bunch of core dumps caused by
3324 printf_filtered("%s") problems.
3326 We eliminated a copyright problem on the rpc and ptrace header files
3327 for VxWorks, which was discovered at the last minute during the 4.7
3328 release. You should now be able to build a VxWorks GDB.
3330 You can now interrupt gdb while an attached process is running. This
3331 will cause the attached process to stop, and give control back to GDB.
3333 We fixed problems caused by using too many file descriptors
3334 for reading symbols from object files and libraries. This was
3335 especially a problem for programs that used many (~100) shared
3338 The `step' command now only enters a subroutine if there is line number
3339 information for the subroutine. Otherwise it acts like the `next'
3340 command. Previously, `step' would enter subroutines if there was
3341 any debugging information about the routine. This avoids problems
3342 when using `cc -g1' on MIPS machines.
3344 * Internal improvements
3346 GDB's internal interfaces have been improved to make it easier to support
3347 debugging of multiple languages in the future.
3349 GDB now uses a common structure for symbol information internally.
3350 Minimal symbols (derived from linkage symbols in object files), partial
3351 symbols (from a quick scan of debug information), and full symbols
3352 contain a common subset of information, making it easier to write
3353 shared code that handles any of them.
3355 * New command line options
3357 We now accept --silent as an alias for --quiet.
3361 The memory-mapped-malloc library is now licensed under the GNU Library
3362 General Public License.
3364 *** Changes in GDB-4.7:
3366 * Host/native/target split
3368 GDB has had some major internal surgery to untangle the support for
3369 hosts and remote targets. Now, when you configure GDB for a remote
3370 target, it will no longer load in all of the support for debugging
3371 local programs on the host. When fully completed and tested, this will
3372 ensure that arbitrary host/target combinations are possible.
3374 The primary conceptual shift is to separate the non-portable code in
3375 GDB into three categories. Host specific code is required any time GDB
3376 is compiled on that host, regardless of the target. Target specific
3377 code relates to the peculiarities of the target, but can be compiled on
3378 any host. Native specific code is everything else: it can only be
3379 built when the host and target are the same system. Child process
3380 handling and core file support are two common `native' examples.
3382 GDB's use of /proc for controlling Unix child processes is now cleaner.
3383 It has been split out into a single module under the `target_ops' vector,
3384 plus two native-dependent functions for each system that uses /proc.
3386 * New hosts supported
3388 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3389 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3390 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3392 * New targets supported
3394 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3395 68030 and CPU32 m68030-*-*, m68332-*-*
3397 * New native hosts supported
3399 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3400 (386bsd is not well tested yet)
3401 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3403 * New file formats supported
3405 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3406 supports reading of `a.out.adobe' object files, which are an a.out
3407 format extended with minimal information about multiple sections.
3411 `show copying' is the same as the old `info copying'.
3412 `show warranty' is the same as `info warrantee'.
3413 These were renamed for consistency. The old commands continue to work.
3415 `info handle' is a new alias for `info signals'.
3417 You can now define pre-command hooks, which attach arbitrary command
3418 scripts to any command. The commands in the hook will be executed
3419 prior to the user's command. You can also create a hook which will be
3420 executed whenever the program stops. See gdb.texinfo.
3424 We now deal with Cfront style name mangling, and can even extract type
3425 info from mangled symbols. GDB can automatically figure out which
3426 symbol mangling style your C++ compiler uses.
3428 Calling of methods and virtual functions has been improved as well.
3432 The crash that occured when debugging Sun Ansi-C compiled binaries is
3433 fixed. This was due to mishandling of the extra N_SO stabs output
3436 We also finally got Ultrix 4.2 running in house, and fixed core file
3437 support, with help from a dozen people on the net.
3439 John M. Farrell discovered that the reason that single-stepping was so
3440 slow on all of the Mips based platforms (primarily SGI and DEC) was
3441 that we were trying to demangle and lookup a symbol used for internal
3442 purposes on every instruction that was being stepped through. Changing
3443 the name of that symbol so that it couldn't be mistaken for a C++
3444 mangled symbol sped things up a great deal.
3446 Rich Pixley sped up symbol lookups in general by getting much smarter
3447 about when C++ symbol mangling is necessary. This should make symbol
3448 completion (TAB on the command line) much faster. It's not as fast as
3449 we'd like, but it's significantly faster than gdb-4.6.
3453 A new user controllable variable 'call_scratch_address' can
3454 specify the location of a scratch area to be used when GDB
3455 calls a function in the target. This is necessary because the
3456 usual method of putting the scratch area on the stack does not work
3457 in systems that have separate instruction and data spaces.
3459 We integrated changes to support the 29k UDI (Universal Debugger
3460 Interface), but discovered at the last minute that we didn't have all
3461 of the appropriate copyright paperwork. We are working with AMD to
3462 resolve this, and hope to have it available soon.
3466 We have sped up the remote serial line protocol, especially for targets
3467 with lots of registers. It now supports a new `expedited status' ('T')
3468 message which can be used in place of the existing 'S' status message.
3469 This allows the remote stub to send only the registers that GDB
3470 needs to make a quick decision about single-stepping or conditional
3471 breakpoints, eliminating the need to fetch the entire register set for
3472 each instruction being stepped through.
3474 The GDB remote serial protocol now implements a write-through cache for
3475 registers, only re-reading the registers if the target has run.
3477 There is also a new remote serial stub for SPARC processors. You can
3478 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3479 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3480 processor with a serial port.
3484 Configure.in files have become much easier to read and modify. A new
3485 `table driven' format makes it more obvious what configurations are
3486 supported, and what files each one uses.
3490 There is a new opcodes library which will eventually contain all of the
3491 disassembly routines and opcode tables. At present, it only contains
3492 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3493 disassembler (binutils/objdump) to share these routines.
3495 The libiberty library is now copylefted under the GNU Library General
3496 Public License. This allows more liberal use, and was done so libg++
3497 can use it. This makes no difference to GDB, since the Library License
3498 grants all the rights from the General Public License.
3502 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3503 reference to the stabs symbol info used by the debugger. It is (as far
3504 as we know) the only published document on this fascinating topic. We
3505 encourage you to read it, compare it to the stabs information on your
3506 system, and send improvements on the document in general (to
3507 bug-gdb@prep.ai.mit.edu).
3509 And, of course, many bugs have been fixed.
3512 *** Changes in GDB-4.6:
3514 * Better support for C++ function names
3516 GDB now accepts as input the "demangled form" of C++ overloaded function
3517 names and member function names, and can do command completion on such names
3518 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3519 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3520 Make use of command completion, it is your friend.
3522 GDB also now accepts a variety of C++ mangled symbol formats. They are
3523 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3524 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3525 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3526 for the list of formats.
3528 * G++ symbol mangling problem
3530 Recent versions of gcc have a bug in how they emit debugging information for
3531 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3532 directory) can be applied to gcc to fix the problem. Alternatively, if you
3533 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3534 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3535 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3538 * New 'maintenance' command
3540 All of the commands related to hacking GDB internals have been moved out of
3541 the main command set, and now live behind the 'maintenance' command. This
3542 can also be abbreviated as 'mt'. The following changes were made:
3544 dump-me -> maintenance dump-me
3545 info all-breakpoints -> maintenance info breakpoints
3546 printmsyms -> maintenance print msyms
3547 printobjfiles -> maintenance print objfiles
3548 printpsyms -> maintenance print psymbols
3549 printsyms -> maintenance print symbols
3551 The following commands are new:
3553 maintenance demangle Call internal GDB demangler routine to
3554 demangle a C++ link name and prints the result.
3555 maintenance print type Print a type chain for a given symbol
3557 * Change to .gdbinit file processing
3559 We now read the $HOME/.gdbinit file before processing the argv arguments
3560 (e.g. reading symbol files or core files). This allows global parameters to
3561 be set, which will apply during the symbol reading. The ./.gdbinit is still
3562 read after argv processing.
3564 * New hosts supported
3566 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3568 GNU/Linux support i386-unknown-linux or linux
3570 We are also including code to support the HP/PA running BSD and HPUX. This
3571 is almost guaranteed not to work, as we didn't have time to test or build it
3572 for this release. We are including it so that the more adventurous (or
3573 masochistic) of you can play with it. We also had major problems with the
3574 fact that the compiler that we got from HP doesn't support the -g option.
3577 * New targets supported
3579 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3581 * More smarts about finding #include files
3583 GDB now remembers the compilation directory for all include files, and for
3584 all files from which C is generated (like yacc and lex sources). This
3585 greatly improves GDB's ability to find yacc/lex sources, and include files,
3586 especially if you are debugging your program from a directory different from
3587 the one that contains your sources.
3589 We also fixed a bug which caused difficulty with listing and setting
3590 breakpoints in include files which contain C code. (In the past, you had to
3591 try twice in order to list an include file that you hadn't looked at before.)
3593 * Interesting infernals change
3595 GDB now deals with arbitrary numbers of sections, where the symbols for each
3596 section must be relocated relative to that section's landing place in the
3597 target's address space. This work was needed to support ELF with embedded
3598 stabs used by Solaris-2.0.
3600 * Bug fixes (of course!)
3602 There have been loads of fixes for the following things:
3603 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3604 i960, stabs, DOS(GO32), procfs, etc...
3606 See the ChangeLog for details.
3608 *** Changes in GDB-4.5:
3610 * New machines supported (host and target)
3612 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3614 SGI Irix-4.x mips-sgi-irix4 or iris4
3616 * New malloc package
3618 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3619 Mmalloc is capable of handling mutiple heaps of memory. It is also
3620 capable of saving a heap to a file, and then mapping it back in later.
3621 This can be used to greatly speedup the startup of GDB by using a
3622 pre-parsed symbol table which lives in a mmalloc managed heap. For
3623 more details, please read mmalloc/mmalloc.texi.
3627 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3628 'help info proc' for details.
3630 * MIPS ecoff symbol table format
3632 The code that reads MIPS symbol table format is now supported on all hosts.
3633 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3636 * File name changes for MS-DOS
3638 Many files in the config directories have been renamed to make it easier to
3639 support GDB on MS-DOSe systems (which have very restrictive file name
3640 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3641 environment) is close to working but has some remaining problems. Note
3642 that debugging of DOS programs is not supported, due to limitations
3643 in the ``operating system'', but it can be used to host cross-debugging.
3645 * Cross byte order fixes
3647 Many fixes have been made to support cross debugging of Sparc and MIPS
3648 targets from hosts whose byte order differs.
3650 * New -mapped and -readnow options
3652 If memory-mapped files are available on your system through the 'mmap'
3653 system call, you can use the -mapped option on the `file' or
3654 `symbol-file' commands to cause GDB to write the symbols from your
3655 program into a reusable file. If the program you are debugging is
3656 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3657 Future GDB debugging sessions will notice the presence of this file,
3658 and will quickly map in symbol information from it, rather than reading
3659 the symbol table from the executable program. Using the '-mapped'
3660 option in a GDB `file' or `symbol-file' command has the same effect as
3661 starting GDB with the '-mapped' command-line option.
3663 You can cause GDB to read the entire symbol table immediately by using
3664 the '-readnow' option with any of the commands that load symbol table
3665 information (or on the GDB command line). This makes the command
3666 slower, but makes future operations faster.
3668 The -mapped and -readnow options are typically combined in order to
3669 build a `fred.syms' file that contains complete symbol information.
3670 A simple GDB invocation to do nothing but build a `.syms' file for future
3673 gdb -batch -nx -mapped -readnow programname
3675 The `.syms' file is specific to the host machine on which GDB is run.
3676 It holds an exact image of GDB's internal symbol table. It cannot be
3677 shared across multiple host platforms.
3679 * longjmp() handling
3681 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3682 siglongjmp() without losing control. This feature has not yet been ported to
3683 all systems. It currently works on many 386 platforms, all MIPS-based
3684 platforms (SGI, DECstation, etc), and Sun3/4.
3688 Preliminary work has been put in to support the new Solaris OS from Sun. At
3689 this time, it can control and debug processes, but it is not capable of
3694 As always, many many bug fixes. The major areas were with g++, and mipsread.
3695 People using the MIPS-based platforms should experience fewer mysterious
3696 crashes and trashed symbol tables.
3698 *** Changes in GDB-4.4:
3700 * New machines supported (host and target)
3702 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3704 BSD Reno on Vax vax-dec-bsd
3705 Ultrix on Vax vax-dec-ultrix
3707 * New machines supported (target)
3709 AMD 29000 embedded, using EBMON a29k-none-none
3713 GDB continues to improve its handling of C++. `References' work better.
3714 The demangler has also been improved, and now deals with symbols mangled as
3715 per the Annotated C++ Reference Guide.
3717 GDB also now handles `stabs' symbol information embedded in MIPS
3718 `ecoff' symbol tables. Since the ecoff format was not easily
3719 extensible to handle new languages such as C++, this appeared to be a
3720 good way to put C++ debugging info into MIPS binaries. This option
3721 will be supported in the GNU C compiler, version 2, when it is
3724 * New features for SVR4
3726 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3727 shared libraries. Debugging dynamically linked programs should present
3728 only minor differences from debugging statically linked programs.
3730 The `info proc' command will print out information about any process
3731 on an SVR4 system (including the one you are debugging). At the moment,
3732 it prints the address mappings of the process.
3734 If you bring up GDB on another SVR4 system, please send mail to
3735 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3737 * Better dynamic linking support in SunOS
3739 Reading symbols from shared libraries which contain debugging symbols
3740 now works properly. However, there remain issues such as automatic
3741 skipping of `transfer vector' code during function calls, which
3742 make it harder to debug code in a shared library, than to debug the
3743 same code linked statically.
3747 GDB is now using the latest `getopt' routines from the FSF. This
3748 version accepts the -- prefix for options with long names. GDB will
3749 continue to accept the old forms (-option and +option) as well.
3750 Various single letter abbreviations for options have been explicity
3751 added to the option table so that they won't get overshadowed in the
3752 future by other options that begin with the same letter.
3756 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3757 Many assorted bugs have been handled. Many more remain to be handled.
3758 See the various ChangeLog files (primarily in gdb and bfd) for details.
3761 *** Changes in GDB-4.3:
3763 * New machines supported (host and target)
3765 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3766 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3767 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3769 * Almost SCO Unix support
3771 We had hoped to support:
3772 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3773 (except for core file support), but we discovered very late in the release
3774 that it has problems with process groups that render gdb unusable. Sorry
3775 about that. I encourage people to fix it and post the fixes.
3777 * Preliminary ELF and DWARF support
3779 GDB can read ELF object files on System V Release 4, and can handle
3780 debugging records for C, in DWARF format, in ELF files. This support
3781 is preliminary. If you bring up GDB on another SVR4 system, please
3782 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3787 GDB now uses the latest `readline' library. One user-visible change
3788 is that two tabs will list possible command completions, which previously
3789 required typing M-? (meta-question mark, or ESC ?).
3793 The `stepi' bug that many of you noticed has been squashed.
3794 Many bugs in C++ have been handled. Many more remain to be handled.
3795 See the various ChangeLog files (primarily in gdb and bfd) for details.
3797 * State of the MIPS world (in case you wondered):
3799 GDB can understand the symbol tables emitted by the compilers
3800 supplied by most vendors of MIPS-based machines, including DEC. These
3801 symbol tables are in a format that essentially nobody else uses.
3803 Some versions of gcc come with an assembler post-processor called
3804 mips-tfile. This program is required if you want to do source-level
3805 debugging of gcc-compiled programs. I believe FSF does not ship
3806 mips-tfile with gcc version 1, but it will eventually come with gcc
3809 Debugging of g++ output remains a problem. g++ version 1.xx does not
3810 really support it at all. (If you're lucky, you should be able to get
3811 line numbers and stack traces to work, but no parameters or local
3812 variables.) With some work it should be possible to improve the
3815 When gcc version 2 is released, you will have somewhat better luck.
3816 However, even then you will get confusing results for inheritance and
3819 We will eventually provide full debugging of g++ output on
3820 DECstations. This will probably involve some kind of stabs-in-ecoff
3821 encapulation, but the details have not been worked out yet.
3824 *** Changes in GDB-4.2:
3826 * Improved configuration
3828 Only one copy of `configure' exists now, and it is not self-modifying.
3829 Porting BFD is simpler.
3833 The `step' and `next' commands now only stop at the first instruction
3834 of a source line. This prevents the multiple stops that used to occur
3835 in switch statements, for-loops, etc. `Step' continues to stop if a
3836 function that has debugging information is called within the line.
3840 Lots of small bugs fixed. More remain.
3842 * New host supported (not target)
3844 Intel 386 PC clone running Mach i386-none-mach
3847 *** Changes in GDB-4.1:
3849 * Multiple source language support
3851 GDB now has internal scaffolding to handle several source languages.
3852 It determines the type of each source file from its filename extension,
3853 and will switch expression parsing and number formatting to match the
3854 language of the function in the currently selected stack frame.
3855 You can also specifically set the language to be used, with
3856 `set language c' or `set language modula-2'.
3860 GDB now has preliminary support for the GNU Modula-2 compiler,
3861 currently under development at the State University of New York at
3862 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3863 continue through the fall of 1991 and into 1992.
3865 Other Modula-2 compilers are currently not supported, and attempting to
3866 debug programs compiled with them will likely result in an error as the
3867 symbol table is read. Feel free to work on it, though!
3869 There are hooks in GDB for strict type checking and range checking,
3870 in the `Modula-2 philosophy', but they do not currently work.
3874 GDB can now write to executable and core files (e.g. patch
3875 a variable's value). You must turn this switch on, specify
3876 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3877 by assigning a new value to a variable. Modifications take
3880 * Automatic SunOS shared library reading
3882 When you run your program, GDB automatically determines where its
3883 shared libraries (if any) have been loaded, and reads their symbols.
3884 The `share' command is no longer needed. This also works when
3885 examining core files.
3889 You can specify the number of lines that the `list' command shows.
3892 * New machines supported (host and target)
3894 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3895 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3896 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3898 * New hosts supported (not targets)
3900 IBM RT/PC: romp-ibm-aix or rtpc
3902 * New targets supported (not hosts)
3904 AMD 29000 embedded with COFF a29k-none-coff
3905 AMD 29000 embedded with a.out a29k-none-aout
3906 Ultracomputer remote kernel debug a29k-nyu-kern
3908 * New remote interfaces
3914 *** Changes in GDB-4.0:
3918 Wide output is wrapped at good places to make the output more readable.
3920 Gdb now supports cross-debugging from a host machine of one type to a
3921 target machine of another type. Communication with the target system
3922 is over serial lines. The ``target'' command handles connecting to the
3923 remote system; the ``load'' command will download a program into the
3924 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3925 also supports debugging of realtime processes running under VxWorks,
3926 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3927 stub on the target system.
3929 New CPUs supported include the AMD 29000 and Intel 960.
3931 GDB now reads object files and symbol tables via a ``binary file''
3932 library, which allows a single copy of GDB to debug programs of multiple
3933 object file types such as a.out and coff.
3935 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3936 refcard.dvi and refcard.ps are available to format it).
3939 * Control-Variable user interface simplified
3941 All variables that control the operation of the debugger can be set
3942 by the ``set'' command, and displayed by the ``show'' command.
3944 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3945 ``Show prompt'' produces the response:
3946 Gdb's prompt is new-gdb=>.
3948 What follows are the NEW set commands. The command ``help set'' will
3949 print a complete list of old and new set commands. ``help set FOO''
3950 will give a longer description of the variable FOO. ``show'' will show
3951 all of the variable descriptions and their current settings.
3953 confirm on/off: Enables warning questions for operations that are
3954 hard to recover from, e.g. rerunning the program while
3955 it is already running. Default is ON.
3957 editing on/off: Enables EMACS style command line editing
3958 of input. Previous lines can be recalled with
3959 control-P, the current line can be edited with control-B,
3960 you can search for commands with control-R, etc.
3963 history filename NAME: NAME is where the gdb command history
3964 will be stored. The default is .gdb_history,
3965 or the value of the environment variable
3968 history size N: The size, in commands, of the command history. The
3969 default is 256, or the value of the environment variable
3972 history save on/off: If this value is set to ON, the history file will
3973 be saved after exiting gdb. If set to OFF, the
3974 file will not be saved. The default is OFF.
3976 history expansion on/off: If this value is set to ON, then csh-like
3977 history expansion will be performed on
3978 command line input. The default is OFF.
3980 radix N: Sets the default radix for input and output. It can be set
3981 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3982 in the current radix, so "set radix 10" is always a no-op.
3984 height N: This integer value is the number of lines on a page. Default
3985 is 24, the current `stty rows'' setting, or the ``li#''
3986 setting from the termcap entry matching the environment
3989 width N: This integer value is the number of characters on a line.
3990 Default is 80, the current `stty cols'' setting, or the ``co#''
3991 setting from the termcap entry matching the environment
3994 Note: ``set screensize'' is obsolete. Use ``set height'' and
3995 ``set width'' instead.
3997 print address on/off: Print memory addresses in various command displays,
3998 such as stack traces and structure values. Gdb looks
3999 more ``symbolic'' if you turn this off; it looks more
4000 ``machine level'' with it on. Default is ON.
4002 print array on/off: Prettyprint arrays. New convenient format! Default
4005 print demangle on/off: Print C++ symbols in "source" form if on,
4008 print asm-demangle on/off: Same, for assembler level printouts
4011 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4014 * Support for Epoch Environment.
4016 The epoch environment is a version of Emacs v18 with windowing. One
4017 new command, ``inspect'', is identical to ``print'', except that if you
4018 are running in the epoch environment, the value is printed in its own
4022 * Support for Shared Libraries
4024 GDB can now debug programs and core files that use SunOS shared libraries.
4025 Symbols from a shared library cannot be referenced
4026 before the shared library has been linked with the program (this
4027 happens after you type ``run'' and before the function main() is entered).
4028 At any time after this linking (including when examining core files
4029 from dynamically linked programs), gdb reads the symbols from each
4030 shared library when you type the ``sharedlibrary'' command.
4031 It can be abbreviated ``share''.
4033 sharedlibrary REGEXP: Load shared object library symbols for files
4034 matching a unix regular expression. No argument
4035 indicates to load symbols for all shared libraries.
4037 info sharedlibrary: Status of loaded shared libraries.
4042 A watchpoint stops execution of a program whenever the value of an
4043 expression changes. Checking for this slows down execution
4044 tremendously whenever you are in the scope of the expression, but is
4045 quite useful for catching tough ``bit-spreader'' or pointer misuse
4046 problems. Some machines such as the 386 have hardware for doing this
4047 more quickly, and future versions of gdb will use this hardware.
4049 watch EXP: Set a watchpoint (breakpoint) for an expression.
4051 info watchpoints: Information about your watchpoints.
4053 delete N: Deletes watchpoint number N (same as breakpoints).
4054 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4055 enable N: Re-enables watchpoint number N (same as breakpoints).
4058 * C++ multiple inheritance
4060 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4063 * C++ exception handling
4065 Gdb now supports limited C++ exception handling. Besides the existing
4066 ability to breakpoint on an exception handler, gdb can breakpoint on
4067 the raising of an exception (before the stack is peeled back to the
4070 catch FOO: If there is a FOO exception handler in the dynamic scope,
4071 set a breakpoint to catch exceptions which may be raised there.
4072 Multiple exceptions (``catch foo bar baz'') may be caught.
4074 info catch: Lists all exceptions which may be caught in the
4075 current stack frame.
4078 * Minor command changes
4080 The command ``call func (arg, arg, ...)'' now acts like the print
4081 command, except it does not print or save a value if the function's result
4082 is void. This is similar to dbx usage.
4084 The ``up'' and ``down'' commands now always print the frame they end up
4085 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4086 frames without printing.
4088 * New directory command
4090 'dir' now adds directories to the FRONT of the source search path.
4091 The path starts off empty. Source files that contain debug information
4092 about the directory in which they were compiled can be found even
4093 with an empty path; Sun CC and GCC include this information. If GDB can't
4094 find your source file in the current directory, type "dir .".
4096 * Configuring GDB for compilation
4098 For normal use, type ``./configure host''. See README or gdb.texinfo
4101 GDB now handles cross debugging. If you are remotely debugging between
4102 two different machines, type ``./configure host -target=targ''.
4103 Host is the machine where GDB will run; targ is the machine
4104 where the program that you are debugging will run.