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 * Tracepoint actions were unified with breakpoint commands. In particular,
75 there are no longer differences in "info break" output for breakpoints and
76 tracepoints and the "commands" command can be used for both tracepoints and
81 ARM Symbian arm*-*-symbianelf*
83 *** Changes in GDB 7.1
89 GDB now supports importing of namespaces in C++. This enables the
90 user to inspect variables from imported namespaces. Support for
91 namepace aliasing has also been added. So, if a namespace is
92 aliased in the current scope (e.g. namepace C=A; ) the user can
93 print variables using the alias (e.g. (gdb) print C::x).
97 All known bugs relating to the printing of virtual base class were
98 fixed. It is now possible to call overloaded static methods using a
103 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
104 and reinterpret_cast<> are now handled by the C++ expression parser.
108 Xilinx MicroBlaze microblaze-*-*
113 Xilinx MicroBlaze microblaze
116 * Multi-program debugging.
118 GDB now has support for multi-program (a.k.a. multi-executable or
119 multi-exec) debugging. This allows for debugging multiple inferiors
120 simultaneously each running a different program under the same GDB
121 session. See "Debugging Multiple Inferiors and Programs" in the
122 manual for more information. This implied some user visible changes
123 in the multi-inferior support. For example, "info inferiors" now
124 lists inferiors that are not running yet or that have exited
125 already. See also "New commands" and "New options" below.
127 * New tracing features
129 GDB's tracepoint facility now includes several new features:
131 ** Trace state variables
133 GDB tracepoints now include support for trace state variables, which
134 are variables managed by the target agent during a tracing
135 experiment. They are useful for tracepoints that trigger each
136 other, so for instance one tracepoint can count hits in a variable,
137 and then a second tracepoint has a condition that is true when the
138 count reaches a particular value. Trace state variables share the
139 $-syntax of GDB convenience variables, and can appear in both
140 tracepoint actions and condition expressions. Use the "tvariable"
141 command to create, and "info tvariables" to view; see "Trace State
142 Variables" in the manual for more detail.
146 GDB now includes an option for defining fast tracepoints, which
147 targets may implement more efficiently, such as by installing a jump
148 into the target agent rather than a trap instruction. The resulting
149 speedup can be by two orders of magnitude or more, although the
150 tradeoff is that some program locations on some target architectures
151 might not allow fast tracepoint installation, for instance if the
152 instruction to be replaced is shorter than the jump. To request a
153 fast tracepoint, use the "ftrace" command, with syntax identical to
154 the regular trace command.
156 ** Disconnected tracing
158 It is now possible to detach GDB from the target while it is running
159 a trace experiment, then reconnect later to see how the experiment
160 is going. In addition, a new variable disconnected-tracing lets you
161 tell the target agent whether to continue running a trace if the
162 connection is lost unexpectedly.
166 GDB now has the ability to save the trace buffer into a file, and
167 then use that file as a target, similarly to you can do with
168 corefiles. You can select trace frames, print data that was
169 collected in them, and use tstatus to display the state of the
170 tracing run at the moment that it was saved. To create a trace
171 file, use "tsave <filename>", and to use it, do "target tfile
174 ** Circular trace buffer
176 You can ask the target agent to handle the trace buffer as a
177 circular buffer, discarding the oldest trace frames to make room for
178 newer ones, by setting circular-trace-buffer to on. This feature may
179 not be available for all target agents.
184 The disassemble command, when invoked with two arguments, now requires
185 the arguments to be comma-separated.
188 The info variables command now displays variable definitions. Files
189 which only declare a variable are not shown.
192 The source command is now capable of sourcing Python scripts.
193 This feature is dependent on the debugger being build with Python
196 Related to this enhancement is also the introduction of a new command
197 "set script-extension" (see below).
199 * New commands (for set/show, see "New options" below)
201 record save [<FILENAME>]
202 Save a file (in core file format) containing the process record
203 execution log for replay debugging at a later time.
205 record restore <FILENAME>
206 Restore the process record execution log that was saved at an
207 earlier time, for replay debugging.
209 add-inferior [-copies <N>] [-exec <FILENAME>]
212 clone-inferior [-copies <N>] [ID]
213 Make a new inferior ready to execute the same program another
219 maint info program-spaces
220 List the program spaces loaded into GDB.
222 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
223 show remote interrupt-sequence
224 Allow the user to select one of ^C, a BREAK signal or BREAK-g
225 as the sequence to the remote target in order to interrupt the execution.
226 Ctrl-C is a default. Some system prefers BREAK which is high level of
227 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
228 Magic SysRq g. It is BREAK signal and character 'g'.
230 set remote interrupt-on-connect [on | off]
231 show remote interrupt-on-connect
232 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
233 remote target when gdb connects to it. This is needed when you debug
236 set remotebreak [on | off]
238 Deprecated. Use "set/show remote interrupt-sequence" instead.
240 tvariable $NAME [ = EXP ]
241 Create or modify a trace state variable.
244 List trace state variables and their values.
246 delete tvariable $NAME ...
247 Delete one or more trace state variables.
250 Evaluate the given expressions without collecting anything into the
251 trace buffer. (Valid in tracepoint actions only.)
253 ftrace FN / FILE:LINE / *ADDR
254 Define a fast tracepoint at the given function, line, or address.
256 * New expression syntax
258 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
259 GDB now parses 0b101010 identically with 42.
263 set follow-exec-mode new|same
264 show follow-exec-mode
265 Control whether GDB reuses the same inferior across an exec call or
266 creates a new one. This is useful to be able to restart the old
267 executable after the inferior having done an exec call.
269 set default-collect EXPR, ...
271 Define a list of expressions to be collected at each tracepoint.
272 This is a useful way to ensure essential items are not overlooked,
273 such as registers or a critical global variable.
275 set disconnected-tracing
276 show disconnected-tracing
277 If set to 1, the target is instructed to continue tracing if it
278 loses its connection to GDB. If 0, the target is to stop tracing
281 set circular-trace-buffer
282 show circular-trace-buffer
283 If set to on, the target is instructed to use a circular trace buffer
284 and discard the oldest trace frames instead of stopping the trace due
285 to a full trace buffer. If set to off, the trace stops when the buffer
286 fills up. Some targets may not support this.
288 set script-extension off|soft|strict
289 show script-extension
290 If set to "off", the debugger does not perform any script language
291 recognition, and all sourced files are assumed to be GDB scripts.
292 If set to "soft" (the default), files are sourced according to
293 filename extension, falling back to GDB scripts if the first
295 If set to "strict", files are sourced according to filename extension.
297 set ada trust-PAD-over-XVS on|off
298 show ada trust-PAD-over-XVS
299 If off, activate a workaround against a bug in the debugging information
300 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
301 the GCC sources for more information about the GNAT encoding and
302 PAD types in particular). It is always safe to set this option to
303 off, but this introduces a slight performance penalty. The default
306 * Python API Improvements
308 ** GDB provides the new class gdb.LazyString. This is useful in
309 some pretty-printing cases. The new method gdb.Value.lazy_string
310 provides a simple way to create objects of this type.
312 ** The fields returned by gdb.Type.fields now have an
313 `is_base_class' attribute.
315 ** The new method gdb.Type.range returns the range of an array type.
317 ** The new method gdb.parse_and_eval can be used to parse and
318 evaluate an expression.
323 Define a trace state variable.
326 Get the current value of a trace state variable.
329 Set desired tracing behavior upon disconnection.
332 Set the trace buffer to be linear or circular.
335 Get data about the tracepoints currently in use.
339 Process record now works correctly with hardware watchpoints.
341 Multiple bug fixes have been made to the mips-irix port, making it
342 much more reliable. In particular:
343 - Debugging threaded applications is now possible again. Previously,
344 GDB would hang while starting the program, or while waiting for
345 the program to stop at a breakpoint.
346 - Attaching to a running process no longer hangs.
347 - An error occurring while loading a core file has been fixed.
348 - Changing the value of the PC register now works again. This fixes
349 problems observed when using the "jump" command, or when calling
350 a function from GDB, or even when assigning a new value to $pc.
351 - With the "finish" and "return" commands, the return value for functions
352 returning a small array is now correctly printed.
353 - It is now possible to break on shared library code which gets executed
354 during a shared library init phase (code executed while executing
355 their .init section). Previously, the breakpoint would have no effect.
356 - GDB is now able to backtrace through the signal handler for
357 non-threaded programs.
359 PIE (Position Independent Executable) programs debugging is now supported.
360 This includes debugging execution of PIC (Position Independent Code) shared
361 libraries although for that, it should be possible to run such libraries as an
364 *** Changes in GDB 7.0
366 * GDB now has an interface for JIT compilation. Applications that
367 dynamically generate code can create symbol files in memory and register
368 them with GDB. For users, the feature should work transparently, and
369 for JIT developers, the interface is documented in the GDB manual in the
370 "JIT Compilation Interface" chapter.
372 * Tracepoints may now be conditional. The syntax is as for
373 breakpoints; either an "if" clause appended to the "trace" command,
374 or the "condition" command is available. GDB sends the condition to
375 the target for evaluation using the same bytecode format as is used
376 for tracepoint actions.
378 * "disassemble" command with a /r modifier, print the raw instructions
379 in hex as well as in symbolic form.
381 * Process record and replay
383 In a architecture environment that supports ``process record and
384 replay'', ``process record and replay'' target can record a log of
385 the process execution, and replay it with both forward and reverse
388 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
389 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
390 set execution-direction {forward|reverse}, for targets that support
393 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
394 feature is available with a native GDB running on kernel version
397 * GDB now has support for multi-byte and wide character sets on the
398 target. Strings whose character type is wchar_t, char16_t, or
399 char32_t are now correctly printed. GDB supports wide- and unicode-
400 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
401 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
402 `printf'. This feature requires iconv to work properly; if your
403 system does not have a working iconv, GDB can use GNU libiconv. See
404 the installation instructions for more information.
406 * GDB now supports automatic retrieval of shared library files from
407 remote targets. To use this feature, specify a system root that begins
408 with the `remote:' prefix, either via the `set sysroot' command or via
409 the `--with-sysroot' configure-time option.
411 * "info sharedlibrary" now takes an optional regex of libraries to show,
412 and it now reports if a shared library has no debugging information.
414 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
415 now complete on file names.
417 * When completing in expressions, gdb will attempt to limit
418 completions to allowable structure or union fields, where appropriate.
419 For instance, consider:
421 # struct example { int f1; double f2; };
422 # struct example variable;
425 If the user types TAB at the end of this command line, the available
426 completions will be "f1" and "f2".
428 * Inlined functions are now supported. They show up in backtraces, and
429 the "step", "next", and "finish" commands handle them automatically.
431 * GDB now supports the token-splicing (##) and stringification (#)
432 operators when expanding macros. It also supports variable-arity
435 * GDB now supports inspecting extra signal information, exported by
436 the new $_siginfo convenience variable. The feature is currently
437 implemented on linux ARM, i386 and amd64.
439 * GDB can now display the VFP floating point registers and NEON vector
440 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
441 can provide these registers (requires Linux 2.6.30 or later). Remote
442 and simulator targets may also provide them.
447 Search memory for a sequence of bytes.
450 Turn off `+'/`-' protocol acknowledgments to permit more efficient
451 operation over reliable transport links. Use of this packet is
452 controlled by the `set remote noack-packet' command.
455 Kill the process with the specified process ID. Use this in preference
456 to `k' when multiprocess protocol extensions are supported.
459 Obtains additional operating system information
463 Read or write additional signal information.
465 * Removed remote protocol undocumented extension
467 An undocumented extension to the remote protocol's `S' stop reply
468 packet that permited the stub to pass a process id was removed.
469 Remote servers should use the `T' stop reply packet instead.
471 * The "disassemble" command now supports an optional /m modifier to print mixed
474 * GDB now supports multiple function calling conventions according to the
475 DWARF-2 DW_AT_calling_convention function attribute.
477 * The SH target utilizes the aforementioned change to distinguish between gcc
478 and Renesas calling convention. It also adds the new CLI commands
479 `set/show sh calling-convention'.
481 * GDB can now read compressed debug sections, as produced by GNU gold
482 with the --compress-debug-sections=zlib flag.
484 * 64-bit core files are now supported on AIX.
486 * Thread switching is now supported on Tru64.
488 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
489 which will be allocated using malloc later in program execution.
491 * The qXfer:libraries:read remote procotol packet now allows passing a
492 list of section offsets.
494 * On GNU/Linux, GDB can now attach to stopped processes. Several race
495 conditions handling signals delivered during attach or thread creation
496 have also been fixed.
498 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
499 From the user's standpoint, all unqualified instances of True and False
500 are treated as the standard definitions, regardless of context.
502 * GDB now parses C++ symbol and type names more flexibly. For
505 template<typename T> class C { };
508 GDB will now correctly handle all of:
510 ptype C<char const *>
512 ptype C<const char *>
515 * New features in the GDB remote stub, gdbserver
517 - The "--wrapper" command-line argument tells gdbserver to use a
518 wrapper program to launch programs for debugging.
520 - On PowerPC and S/390 targets, it is now possible to use a single
521 gdbserver executable to debug both 32-bit and 64-bit programs.
522 (This requires gdbserver itself to be built as a 64-bit executable.)
524 - gdbserver uses the new noack protocol mode for TCP connections to
525 reduce communications latency, if also supported and enabled in GDB.
527 - Support for the sparc64-linux-gnu target is now included in
530 - The amd64-linux build of gdbserver now supports debugging both
531 32-bit and 64-bit programs.
533 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
534 now support hardware watchpoints, and will use them automatically
539 GDB now has support for scripting using Python. Whether this is
540 available is determined at configure time.
542 New GDB commands can now be written in Python.
544 * Ada tasking support
546 Ada tasks can now be inspected in GDB. The following commands have
550 Print the list of Ada tasks.
552 Print detailed information about task number N.
554 Print the task number of the current task.
556 Switch the context of debugging to task number N.
558 * Support for user-defined prefixed commands. The "define" command can
559 add new commands to existing prefixes, e.g. "target".
561 * Multi-inferior, multi-process debugging.
563 GDB now has generalized support for multi-inferior debugging. See
564 "Debugging Multiple Inferiors" in the manual for more information.
565 Although availability still depends on target support, the command
566 set is more uniform now. The GNU/Linux specific multi-forks support
567 has been migrated to this new framework. This implied some user
568 visible changes; see "New commands" and also "Removed commands"
571 * Target descriptions can now describe the target OS ABI. See the
572 "Target Description Format" section in the user manual for more
575 * Target descriptions can now describe "compatible" architectures
576 to indicate that the target can execute applications for a different
577 architecture in addition to those for the main target architecture.
578 See the "Target Description Format" section in the user manual for
581 * Multi-architecture debugging.
583 GDB now includes general supports for debugging applications on
584 hybrid systems that use more than one single processor architecture
585 at the same time. Each such hybrid architecture still requires
586 specific support to be added. The only hybrid architecture supported
587 in this version of GDB is the Cell Broadband Engine.
589 * GDB now supports integrated debugging of Cell/B.E. applications that
590 use both the PPU and SPU architectures. To enable support for hybrid
591 Cell/B.E. debugging, you need to configure GDB to support both the
592 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
593 --enable-targets configure option.
595 * Non-stop mode debugging.
597 For some targets, GDB now supports an optional mode of operation in
598 which you can examine stopped threads while other threads continue
599 to execute freely. This is referred to as non-stop mode, with the
600 old mode referred to as all-stop mode. See the "Non-Stop Mode"
601 section in the user manual for more information.
603 To be able to support remote non-stop debugging, a remote stub needs
604 to implement the non-stop mode remote protocol extensions, as
605 described in the "Remote Non-Stop" section of the user manual. The
606 GDB remote stub, gdbserver, has been adjusted to support these
607 extensions on linux targets.
609 * New commands (for set/show, see "New options" below)
611 catch syscall [NAME(S) | NUMBER(S)]
612 Catch system calls. Arguments, which should be names of system
613 calls or their numbers, mean catch only those syscalls. Without
614 arguments, every syscall will be caught. When the inferior issues
615 any of the specified syscalls, GDB will stop and announce the system
616 call, both when it is called and when its call returns. This
617 feature is currently available with a native GDB running on the
618 Linux Kernel, under the following architectures: x86, x86_64,
619 PowerPC and PowerPC64.
621 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
623 Search memory for a sequence of bytes.
625 maint set python print-stack
626 maint show python print-stack
627 Show a stack trace when an error is encountered in a Python script.
630 Invoke CODE by passing it to the Python interpreter.
635 These allow macros to be defined, undefined, and listed
639 Show operating system information about processes.
642 List the inferiors currently under GDB's control.
645 Switch focus to inferior number NUM.
648 Detach from inferior number NUM.
651 Kill inferior number NUM.
656 show spu stop-on-load
657 Control whether to stop for new SPE threads during Cell/B.E. debugging.
659 set spu auto-flush-cache
660 show spu auto-flush-cache
661 Control whether to automatically flush the software-managed cache
662 during Cell/B.E. debugging.
664 set sh calling-convention
665 show sh calling-convention
666 Control the calling convention used when calling SH target functions.
670 Control display of timestamps with GDB debugging output.
672 set disassemble-next-line
673 show disassemble-next-line
674 Control display of disassembled source lines or instructions when
677 set remote noack-packet
678 show remote noack-packet
679 Set/show the use of remote protocol QStartNoAckMode packet. See above
680 under "New remote packets."
682 set remote query-attached-packet
683 show remote query-attached-packet
684 Control use of remote protocol `qAttached' (query-attached) packet.
686 set remote read-siginfo-object
687 show remote read-siginfo-object
688 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
691 set remote write-siginfo-object
692 show remote write-siginfo-object
693 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
696 set remote reverse-continue
697 show remote reverse-continue
698 Control use of remote protocol 'bc' (reverse-continue) packet.
700 set remote reverse-step
701 show remote reverse-step
702 Control use of remote protocol 'bs' (reverse-step) packet.
704 set displaced-stepping
705 show displaced-stepping
706 Control displaced stepping mode. Displaced stepping is a way to
707 single-step over breakpoints without removing them from the debuggee.
708 Also known as "out-of-line single-stepping".
712 Control display of debugging info for displaced stepping.
714 maint set internal-error
715 maint show internal-error
716 Control what GDB does when an internal error is detected.
718 maint set internal-warning
719 maint show internal-warning
720 Control what GDB does when an internal warning is detected.
725 Use a wrapper program to launch programs for debugging.
727 set multiple-symbols (all|ask|cancel)
728 show multiple-symbols
729 The value of this variable can be changed to adjust the debugger behavior
730 when an expression or a breakpoint location contains an ambiguous symbol
731 name (an overloaded function name, for instance).
733 set breakpoint always-inserted
734 show breakpoint always-inserted
735 Keep breakpoints always inserted in the target, as opposed to inserting
736 them when resuming the target, and removing them when the target stops.
737 This option can improve debugger performance on slow remote targets.
739 set arm fallback-mode (arm|thumb|auto)
740 show arm fallback-mode
741 set arm force-mode (arm|thumb|auto)
743 These commands control how ARM GDB determines whether instructions
744 are ARM or Thumb. The default for both settings is auto, which uses
745 the current CPSR value for instructions without symbols; previous
746 versions of GDB behaved as if "set arm fallback-mode arm".
748 set disable-randomization
749 show disable-randomization
750 Standalone programs run with the virtual address space randomization enabled
751 by default on some platforms. This option keeps the addresses stable across
752 multiple debugging sessions.
756 Control whether other threads are stopped or not when some thread hits
761 Requests that asynchronous execution is enabled in the target, if available.
762 In this case, it's possible to resume target in the background, and interact
763 with GDB while the target is running. "show target-async" displays the
764 current state of asynchronous execution of the target.
766 set target-wide-charset
767 show target-wide-charset
768 The target-wide-charset is the name of the character set that GDB
769 uses when printing characters whose type is wchar_t.
771 set tcp auto-retry (on|off)
773 set tcp connect-timeout
774 show tcp connect-timeout
775 These commands allow GDB to retry failed TCP connections to a remote stub
776 with a specified timeout period; this is useful if the stub is launched
777 in parallel with GDB but may not be ready to accept connections immediately.
779 set libthread-db-search-path
780 show libthread-db-search-path
781 Control list of directories which GDB will search for appropriate
784 set schedule-multiple (on|off)
785 show schedule-multiple
786 Allow GDB to resume all threads of all processes or only threads of
791 Use more aggressive caching for accesses to the stack. This improves
792 performance of remote debugging (particularly backtraces) without
793 affecting correctness.
795 set interactive-mode (on|off|auto)
796 show interactive-mode
797 Control whether GDB runs in interactive mode (on) or not (off).
798 When in interactive mode, GDB waits for the user to answer all
799 queries. Otherwise, GDB does not wait and assumes the default
800 answer. When set to auto (the default), GDB determines which
801 mode to use based on the stdin settings.
806 For program forks, this is replaced by the new more generic `info
807 inferiors' command. To list checkpoints, you can still use the
808 `info checkpoints' command, which was an alias for the `info forks'
812 Replaced by the new `inferior' command. To switch between
813 checkpoints, you can still use the `restart' command, which was an
814 alias for the `fork' command.
817 This is removed, since some targets don't have a notion of
818 processes. To switch between processes, you can still use the
819 `inferior' command using GDB's own inferior number.
822 For program forks, this is replaced by the new more generic `kill
823 inferior' command. To delete a checkpoint, you can still use the
824 `delete checkpoint' command, which was an alias for the `delete
828 For program forks, this is replaced by the new more generic `detach
829 inferior' command. To detach a checkpoint, you can still use the
830 `detach checkpoint' command, which was an alias for the `detach
833 * New native configurations
835 x86/x86_64 Darwin i[34567]86-*-darwin*
837 x86_64 MinGW x86_64-*-mingw*
841 Lattice Mico32 lm32-*
842 x86 DICOS i[34567]86-*-dicos*
843 x86_64 DICOS x86_64-*-dicos*
846 * The GDB remote stub, gdbserver, now supports x86 Windows CE
847 (mingw32ce) debugging.
853 These commands were actually not implemented on any target.
855 *** Changes in GDB 6.8
857 * New native configurations
859 NetBSD/hppa hppa*-*netbsd*
860 Xtensa GNU/Linux xtensa*-*-linux*
864 NetBSD/hppa hppa*-*-netbsd*
865 Xtensa GNU/Lunux xtensa*-*-linux*
867 * Change in command line behavior -- corefiles vs. process ids.
869 When the '-p NUMBER' or '--pid NUMBER' options are used, and
870 attaching to process NUMBER fails, GDB no longer attempts to open a
871 core file named NUMBER. Attaching to a program using the -c option
872 is no longer supported. Instead, use the '-p' or '--pid' options.
874 * GDB can now be built as a native debugger for debugging Windows x86
875 (mingw32) Portable Executable (PE) programs.
877 * Pending breakpoints no longer change their number when their address
880 * GDB now supports breakpoints with multiple locations,
881 including breakpoints on C++ constructors, inside C++ templates,
882 and in inlined functions.
884 * GDB's ability to debug optimized code has been improved. GDB more
885 accurately identifies function bodies and lexical blocks that occupy
886 more than one contiguous range of addresses.
888 * Target descriptions can now describe registers for PowerPC.
890 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
891 registers on PowerPC targets.
893 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
894 targets even when the libthread_db library is not available.
896 * The GDB remote stub, gdbserver, now supports the new file transfer
897 commands (remote put, remote get, and remote delete).
899 * The GDB remote stub, gdbserver, now supports run and attach in
900 extended-remote mode.
902 * hppa*64*-*-hpux11* target broken
903 The debugger is unable to start a program and fails with the following
904 error: "Error trying to get information about dynamic linker".
905 The gdb-6.7 release is also affected.
907 * GDB now supports the --enable-targets= configure option to allow
908 building a single GDB executable that supports multiple remote
909 target architectures.
911 * GDB now supports debugging C and C++ programs which use the
912 Decimal Floating Point extension. In addition, the PowerPC target
913 now has a set of pseudo-registers to inspect decimal float values
914 stored in two consecutive float registers.
916 * The -break-insert MI command can optionally create pending
919 * Improved support for debugging Ada
920 Many improvements to the Ada language support have been made. These
922 - Better support for Ada2005 interface types
923 - Improved handling of arrays and slices in general
924 - Better support for Taft-amendment types
925 - The '{type} ADDRESS' expression is now allowed on the left hand-side
927 - Improved command completion in Ada
930 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
935 set print frame-arguments (all|scalars|none)
936 show print frame-arguments
937 The value of this variable can be changed to control which argument
938 values should be printed by the debugger when displaying a frame.
943 Transfer files to and from a remote target, and delete remote files.
950 Transfer files to and from a remote target, and delete remote files.
959 Open, close, read, write, and delete files on the remote system.
962 Attach to an existing process on the remote system, in extended-remote
966 Run a new process on the remote system, in extended-remote mode.
968 *** Changes in GDB 6.7
970 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
971 bfd, libiberty and opcodes, as revealed by static analysis donated by
972 Coverity, Inc. (http://scan.coverity.com).
974 * When looking up multiply-defined global symbols, GDB will now prefer the
975 symbol definition in the current shared library if it was built using the
976 -Bsymbolic linker option.
978 * When the Text User Interface (TUI) is not configured, GDB will now
979 recognize the -tui command-line option and print a message that the TUI
982 * The GDB remote stub, gdbserver, now has lower overhead for high
983 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
985 * GDB for MIPS targets now autodetects whether a remote target provides
986 32-bit or 64-bit register values.
988 * Support for C++ member pointers has been improved.
990 * GDB now understands XML target descriptions, which specify the
991 target's overall architecture. GDB can read a description from
992 a local file or over the remote serial protocol.
994 * Vectors of single-byte data use a new integer type which is not
995 automatically displayed as character or string data.
997 * The /s format now works with the print command. It displays
998 arrays of single-byte integers and pointers to single-byte integers
1001 * Target descriptions can now describe target-specific registers,
1002 for architectures which have implemented the support (currently
1003 only ARM, M68K, and MIPS).
1005 * GDB and the GDB remote stub, gdbserver, now support the XScale
1008 * The GDB remote stub, gdbserver, has been updated to support
1009 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1010 has been rewritten to use the standard GDB remote protocol.
1012 * GDB can now step into C++ functions which are called through thunks.
1014 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1016 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1017 layout. It also supports a TextSeg= and DataSeg= response when only
1018 segment base addresses (rather than offsets) are available.
1020 * The /i format now outputs any trailing branch delay slot instructions
1021 immediately following the last instruction within the count specified.
1023 * The GDB remote protocol "T" stop reply packet now supports a
1024 "library" response. Combined with the new "qXfer:libraries:read"
1025 packet, this response allows GDB to debug shared libraries on targets
1026 where the operating system manages the list of loaded libraries (e.g.
1027 Windows and SymbianOS).
1029 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1030 (DLLs) on Windows and Windows CE targets.
1032 * GDB now supports a faster verification that a .debug file matches its binary
1033 according to its build-id signature, if the signature is present.
1039 Enable or disable hardware flow control (RTS/CTS) on the serial port
1040 when debugging using remote targets.
1042 set mem inaccessible-by-default
1043 show mem inaccessible-by-default
1044 If the target supplies a memory map, for instance via the remote
1045 protocol's "qXfer:memory-map:read" packet, setting this variable
1046 prevents GDB from accessing memory outside the memory map. This
1047 is useful for targets with memory mapped registers or which react
1048 badly to accesses of unmapped address space.
1050 set breakpoint auto-hw
1051 show breakpoint auto-hw
1052 If the target supplies a memory map, for instance via the remote
1053 protocol's "qXfer:memory-map:read" packet, setting this variable
1054 lets GDB use hardware breakpoints automatically for memory regions
1055 where it can not use software breakpoints. This covers both the
1056 "break" command and internal breakpoints used for other commands
1057 including "next" and "finish".
1060 catch exception unhandled
1061 Stop the program execution when Ada exceptions are raised.
1064 Stop the program execution when an Ada assertion failed.
1068 Set an alternate system root for target files. This is a more
1069 general version of "set solib-absolute-prefix", which is now
1070 an alias to "set sysroot".
1073 Provide extended SPU facility status information. This set of
1074 commands is available only when debugging the Cell/B.E. SPU
1077 * New native configurations
1079 OpenBSD/sh sh*-*openbsd*
1082 unset tdesc filename
1084 Use the specified local file as an XML target description, and do
1085 not query the target for its built-in description.
1089 OpenBSD/sh sh*-*-openbsd*
1090 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1091 Toshiba Media Processor mep-elf
1093 * New remote packets
1096 Ignore the specified signals; pass them directly to the debugged program
1097 without stopping other threads or reporting them to GDB.
1099 qXfer:features:read:
1100 Read an XML target description from the target, which describes its
1105 Read or write contents of an spufs file on the target system. These
1106 packets are available only on the Cell/B.E. SPU architecture.
1108 qXfer:libraries:read:
1109 Report the loaded shared libraries. Combined with new "T" packet
1110 response, this packet allows GDB to debug shared libraries on
1111 targets where the operating system manages the list of loaded
1112 libraries (e.g. Windows and SymbianOS).
1116 Support for these obsolete configurations has been removed.
1124 i[34567]86-*-lynxos*
1125 i[34567]86-*-netware*
1126 i[34567]86-*-sco3.2v5*
1127 i[34567]86-*-sco3.2v4*
1129 i[34567]86-*-sysv4.2*
1132 i[34567]86-*-unixware2*
1133 i[34567]86-*-unixware*
1142 * Other removed features
1149 Various m68k-only ROM monitors.
1156 Various Renesas ROM monitors and debugging interfaces for SH and
1161 Support for a Macraigor serial interface to on-chip debugging.
1162 GDB does not directly support the newer parallel or USB
1167 A debug information format. The predecessor to DWARF 2 and
1168 DWARF 3, which are still supported.
1170 Support for the HP aCC compiler on HP-UX/PA-RISC
1172 SOM-encapsulated symbolic debugging information, automatic
1173 invocation of pxdb, and the aCC custom C++ ABI. This does not
1174 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1175 with aCC can still be debugged on an assembly level.
1177 MIPS ".pdr" sections
1179 A MIPS-specific format used to describe stack frame layout
1180 in debugging information.
1184 GDB could work with an older version of Guile to debug
1185 the interpreter and Scheme programs running in it.
1187 set mips stack-arg-size
1188 set mips saved-gpreg-size
1190 Use "set mips abi" to control parameter passing for MIPS.
1192 *** Changes in GDB 6.6
1197 Cell Broadband Engine SPU spu-elf
1199 * GDB can now be configured as a cross-debugger targeting native Windows
1200 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1201 running on a Windows system over TCP/IP to debug Windows programs.
1203 * The GDB remote stub, gdbserver, has been updated to support Windows and
1204 Cygwin debugging. Both single-threaded and multi-threaded programs are
1207 * The "set trust-readonly-sections" command works again. This command was
1208 broken in GDB 6.3, 6.4, and 6.5.
1210 * The "load" command now supports writing to flash memory, if the remote
1211 stub provides the required support.
1213 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1214 longer requires symbolic debug information (e.g. DWARF-2).
1219 unset substitute-path
1220 show substitute-path
1221 Manage a list of substitution rules that GDB uses to rewrite the name
1222 of the directories where the sources are located. This can be useful
1223 for instance when the sources were moved to a different location
1224 between compilation and debugging.
1228 Print each CLI command as it is executed. Each command is prefixed with
1229 a number of `+' symbols representing the nesting depth.
1230 The source command now has a `-v' option to enable the same feature.
1234 The ARM Demon monitor support (RDP protocol, "target rdp").
1236 Kernel Object Display, an embedded debugging feature which only worked with
1237 an obsolete version of Cisco IOS.
1239 The 'set download-write-size' and 'show download-write-size' commands.
1241 * New remote packets
1244 Tell a stub about GDB client features, and request remote target features.
1245 The first feature implemented is PacketSize, which allows the target to
1246 specify the size of packets it can handle - to minimize the number of
1247 packets required and improve performance when connected to a remote
1251 Fetch an OS auxilliary vector from the remote stub. This packet is a
1252 more efficient replacement for qPart:auxv:read.
1254 qXfer:memory-map:read:
1255 Fetch a memory map from the remote stub, including information about
1256 RAM, ROM, and flash memory devices.
1261 Erase and program a flash memory device.
1263 * Removed remote packets
1266 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1267 used it, and only gdbserver implemented it.
1269 *** Changes in GDB 6.5
1273 Renesas M32C/M16C m32c-elf
1275 Morpho Technologies ms1 ms1-elf
1279 init-if-undefined Initialize a convenience variable, but
1280 only if it doesn't already have a value.
1282 The following commands are presently only implemented for native GNU/Linux:
1284 checkpoint Save a snapshot of the program state.
1286 restart <n> Return the program state to a
1287 previously saved state.
1289 info checkpoints List currently saved checkpoints.
1291 delete-checkpoint <n> Delete a previously saved checkpoint.
1293 set|show detach-on-fork Tell gdb whether to detach from a newly
1294 forked process, or to keep debugging it.
1296 info forks List forks of the user program that
1297 are available to be debugged.
1299 fork <n> Switch to debugging one of several
1300 forks of the user program that are
1301 available to be debugged.
1303 delete-fork <n> Delete a fork from the list of forks
1304 that are available to be debugged (and
1305 kill the forked process).
1307 detach-fork <n> Delete a fork from the list of forks
1308 that are available to be debugged (and
1309 allow the process to continue).
1313 Morpho Technologies ms2 ms1-elf
1315 * Improved Windows host support
1317 GDB now builds as a cross debugger hosted on i686-mingw32, including
1318 native console support, and remote communications using either
1319 network sockets or serial ports.
1321 * Improved Modula-2 language support
1323 GDB can now print most types in the Modula-2 syntax. This includes:
1324 basic types, set types, record types, enumerated types, range types,
1325 pointer types and ARRAY types. Procedure var parameters are correctly
1326 printed and hexadecimal addresses and character constants are also
1327 written in the Modula-2 syntax. Best results can be obtained by using
1328 GNU Modula-2 together with the -gdwarf-2 command line option.
1332 The ARM rdi-share module.
1334 The Netware NLM debug server.
1336 *** Changes in GDB 6.4
1338 * New native configurations
1340 OpenBSD/arm arm*-*-openbsd*
1341 OpenBSD/mips64 mips64-*-openbsd*
1345 Morpho Technologies ms1 ms1-elf
1347 * New command line options
1349 --batch-silent As for --batch, but totally silent.
1350 --return-child-result The debugger will exist with the same value
1351 the child (debugged) program exited with.
1352 --eval-command COMMAND, -ex COMMAND
1353 Execute a single GDB CLI command. This may be
1354 specified multiple times and in conjunction
1355 with the --command (-x) option.
1357 * Deprecated commands removed
1359 The following commands, that were deprecated in 2000, have been
1363 set|show arm disassembly-flavor set|show arm disassembler
1364 othernames set arm disassembler
1365 set|show remotedebug set|show debug remote
1366 set|show archdebug set|show debug arch
1367 set|show eventdebug set|show debug event
1370 * New BSD user-level threads support
1372 It is now possible to debug programs using the user-level threads
1373 library on OpenBSD and FreeBSD. Currently supported (target)
1376 FreeBSD/amd64 x86_64-*-freebsd*
1377 FreeBSD/i386 i386-*-freebsd*
1378 OpenBSD/i386 i386-*-openbsd*
1380 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1381 are not yet supported.
1383 * New support for Matsushita MN10300 w/sim added
1384 (Work in progress). mn10300-elf.
1386 * REMOVED configurations and files
1388 VxWorks and the XDR protocol *-*-vxworks
1389 Motorola MCORE mcore-*-*
1390 National Semiconductor NS32000 ns32k-*-*
1392 * New "set print array-indexes" command
1394 After turning this setting "on", GDB prints the index of each element
1395 when displaying arrays. The default is "off" to preserve the previous
1398 * VAX floating point support
1400 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1402 * User-defined command support
1404 In addition to using $arg0..$arg9 for argument passing, it is now possible
1405 to use $argc to determine now many arguments have been passed. See the
1406 section on user-defined commands in the user manual for more information.
1408 *** Changes in GDB 6.3:
1410 * New command line option
1412 GDB now accepts -l followed by a number to set the timeout for remote
1415 * GDB works with GCC -feliminate-dwarf2-dups
1417 GDB now supports a more compact representation of DWARF-2 debug
1418 information using DW_FORM_ref_addr references. These are produced
1419 by GCC with the option -feliminate-dwarf2-dups and also by some
1420 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1421 to use -feliminate-dwarf2-dups.
1423 * Internationalization
1425 When supported by the host system, GDB will be built with
1426 internationalization (libintl). The task of marking up the sources is
1427 continued, we're looking forward to our first translation.
1431 Initial support for debugging programs compiled with the GNAT
1432 implementation of the Ada programming language has been integrated
1433 into GDB. In this release, support is limited to expression evaluation.
1435 * New native configurations
1437 GNU/Linux/m32r m32r-*-linux-gnu
1441 GDB's remote protocol now includes support for the 'p' packet. This
1442 packet is used to fetch individual registers from a remote inferior.
1444 * END-OF-LIFE registers[] compatibility module
1446 GDB's internal register infrastructure has been completely rewritten.
1447 The new infrastructure making possible the implementation of key new
1448 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1451 GDB 6.3 will be the last release to include the the registers[]
1452 compatibility module that allowed out-of-date configurations to
1453 continue to work. This change directly impacts the following
1463 powerpc bdm protocol
1465 Unless there is activity to revive these configurations, they will be
1466 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1468 * OBSOLETE configurations and files
1470 Configurations that have been declared obsolete in this release have
1471 been commented out. Unless there is activity to revive these
1472 configurations, the next release of GDB will have their sources
1473 permanently REMOVED.
1482 *** Changes in GDB 6.2.1:
1484 * MIPS `break main; run' gave an heuristic-fence-post warning
1486 When attempting to run even a simple program, a warning about
1487 heuristic-fence-post being hit would be reported. This problem has
1490 * MIPS IRIX 'long double' crashed GDB
1492 When examining a long double variable, GDB would get a segmentation
1493 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1494 IRIX long double values).
1498 A bug in the VAX stack code was causing problems with the "next"
1499 command. This problem has been fixed.
1501 *** Changes in GDB 6.2:
1503 * Fix for ``many threads''
1505 On GNU/Linux systems that use the NPTL threads library, a program
1506 rapidly creating and deleting threads would confuse GDB leading to the
1509 ptrace: No such process.
1510 thread_db_get_info: cannot get thread info: generic error
1512 This problem has been fixed.
1514 * "-async" and "-noasync" options removed.
1516 Support for the broken "-noasync" option has been removed (it caused
1519 * New ``start'' command.
1521 This command runs the program until the begining of the main procedure.
1523 * New BSD Kernel Data Access Library (libkvm) interface
1525 Using ``target kvm'' it is now possible to debug kernel core dumps and
1526 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1527 platforms. Currently supported (native-only) configurations are:
1529 FreeBSD/amd64 x86_64-*-freebsd*
1530 FreeBSD/i386 i?86-*-freebsd*
1531 NetBSD/i386 i?86-*-netbsd*
1532 NetBSD/m68k m68*-*-netbsd*
1533 NetBSD/sparc sparc-*-netbsd*
1534 OpenBSD/amd64 x86_64-*-openbsd*
1535 OpenBSD/i386 i?86-*-openbsd*
1536 OpenBSD/m68k m68*-openbsd*
1537 OpenBSD/sparc sparc-*-openbsd*
1539 * Signal trampoline code overhauled
1541 Many generic problems with GDB's signal handling code have been fixed.
1542 These include: backtraces through non-contiguous stacks; recognition
1543 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1544 call; backtrace through a signal trampoline; step into and out of
1545 signal handlers; and single-stepping in the signal trampoline.
1547 Please note that kernel bugs are a limiting factor here. These
1548 features have been shown to work on an s390 GNU/Linux system that
1549 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1551 * Cygwin support for DWARF 2 added.
1553 * New native configurations
1555 GNU/Linux/hppa hppa*-*-linux*
1556 OpenBSD/hppa hppa*-*-openbsd*
1557 OpenBSD/m68k m68*-*-openbsd*
1558 OpenBSD/m88k m88*-*-openbsd*
1559 OpenBSD/powerpc powerpc-*-openbsd*
1560 NetBSD/vax vax-*-netbsd*
1561 OpenBSD/vax vax-*-openbsd*
1563 * END-OF-LIFE frame compatibility module
1565 GDB's internal frame infrastructure has been completely rewritten.
1566 The new infrastructure making it possible to support key new features
1567 including DWARF 2 Call Frame Information. To aid in the task of
1568 migrating old configurations to this new infrastructure, a
1569 compatibility module, that allowed old configurations to continue to
1570 work, was also included.
1572 GDB 6.2 will be the last release to include this frame compatibility
1573 module. This change directly impacts the following configurations:
1583 Unless there is activity to revive these configurations, they will be
1584 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1586 * REMOVED configurations and files
1588 Sun 3, running SunOS 3 m68*-*-sunos3*
1589 Sun 3, running SunOS 4 m68*-*-sunos4*
1590 Sun 2, running SunOS 3 m68000-*-sunos3*
1591 Sun 2, running SunOS 4 m68000-*-sunos4*
1592 Motorola 680x0 running LynxOS m68*-*-lynxos*
1593 AT&T 3b1/Unix pc m68*-att-*
1594 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1595 decstation mips-dec-* mips-little-*
1596 riscos mips-*-riscos* mips-*-sysv*
1597 sonymips mips-sony-*
1598 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1600 *** Changes in GDB 6.1.1:
1602 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1604 The TUI (Text-mode User Interface) is now built as part of a default
1605 GDB configuration. It is enabled by either selecting the TUI with the
1606 command line option "-i=tui" or by running the separate "gdbtui"
1607 program. For more information on the TUI, see the manual "Debugging
1610 * Pending breakpoint support (also included in GDB 6.1)
1612 Support has been added to allow you to specify breakpoints in shared
1613 libraries that have not yet been loaded. If a breakpoint location
1614 cannot be found, and the "breakpoint pending" option is set to auto,
1615 GDB queries you if you wish to make the breakpoint pending on a future
1616 shared-library load. If and when GDB resolves the breakpoint symbol,
1617 the pending breakpoint is removed as one or more regular breakpoints
1620 Pending breakpoints are very useful for GCJ Java debugging.
1622 * Fixed ISO-C build problems
1624 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1625 non ISO-C code that stopped them being built using a more strict ISO-C
1626 compiler (e.g., IBM's C compiler).
1628 * Fixed build problem on IRIX 5
1630 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1631 wasn't able to compile compile on an IRIX 5 system.
1633 * Added execute permission to gdb/gdbserver/configure
1635 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1636 permission. This bug would cause configure to fail on a number of
1637 systems (Solaris, IRIX). Ref: server/519.
1639 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1641 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1642 has been updated to use constant array sizes.
1644 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1646 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1647 its generated DWARF Call Frame Info. This encoding was causing GDB to
1648 panic, that panic has been fixed. Ref: gdb/1628.
1650 * Fixed a problem when examining parameters in shared library code.
1652 When examining parameters in optimized shared library code generated
1653 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1654 not available''. GDB now correctly displays the variable's value.
1656 *** Changes in GDB 6.1:
1658 * Removed --with-mmalloc
1660 Support for the mmalloc memory manager has been removed, as it
1661 conflicted with the internal gdb byte cache.
1663 * Changes in AMD64 configurations
1665 The AMD64 target now includes the %cs and %ss registers. As a result
1666 the AMD64 remote protocol has changed; this affects the floating-point
1667 and SSE registers. If you rely on those registers for your debugging,
1668 you should upgrade gdbserver on the remote side.
1670 * Revised SPARC target
1672 The SPARC target has been completely revised, incorporating the
1673 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1674 support for LynxOS and SunOS 4 has been dropped. Calling functions
1675 from within GDB on operating systems with a non-executable stack
1676 (Solaris, OpenBSD) now works.
1680 GDB has a new C++ demangler which does a better job on the mangled
1681 names generated by current versions of g++. It also runs faster, so
1682 with this and other changes gdb should now start faster on large C++
1685 * DWARF 2 Location Expressions
1687 GDB support for location expressions has been extended to support function
1688 arguments and frame bases. Older versions of GDB could crash when they
1691 * C++ nested types and namespaces
1693 GDB's support for nested types and namespaces in C++ has been
1694 improved, especially if you use the DWARF 2 debugging format. (This
1695 is the default for recent versions of GCC on most platforms.)
1696 Specifically, if you have a class "Inner" defined within a class or
1697 namespace "Outer", then GDB realizes that the class's name is
1698 "Outer::Inner", not simply "Inner". This should greatly reduce the
1699 frequency of complaints about not finding RTTI symbols. In addition,
1700 if you are stopped at inside of a function defined within a namespace,
1701 GDB modifies its name lookup accordingly.
1703 * New native configurations
1705 NetBSD/amd64 x86_64-*-netbsd*
1706 OpenBSD/amd64 x86_64-*-openbsd*
1707 OpenBSD/alpha alpha*-*-openbsd*
1708 OpenBSD/sparc sparc-*-openbsd*
1709 OpenBSD/sparc64 sparc64-*-openbsd*
1711 * New debugging protocols
1713 M32R with SDI protocol m32r-*-elf*
1715 * "set prompt-escape-char" command deleted.
1717 The command "set prompt-escape-char" has been deleted. This command,
1718 and its very obscure effet on GDB's prompt, was never documented,
1719 tested, nor mentioned in the NEWS file.
1721 * OBSOLETE configurations and files
1723 Configurations that have been declared obsolete in this release have
1724 been commented out. Unless there is activity to revive these
1725 configurations, the next release of GDB will have their sources
1726 permanently REMOVED.
1728 Sun 3, running SunOS 3 m68*-*-sunos3*
1729 Sun 3, running SunOS 4 m68*-*-sunos4*
1730 Sun 2, running SunOS 3 m68000-*-sunos3*
1731 Sun 2, running SunOS 4 m68000-*-sunos4*
1732 Motorola 680x0 running LynxOS m68*-*-lynxos*
1733 AT&T 3b1/Unix pc m68*-att-*
1734 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1735 decstation mips-dec-* mips-little-*
1736 riscos mips-*-riscos* mips-*-sysv*
1737 sonymips mips-sony-*
1738 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1740 * REMOVED configurations and files
1742 SGI Irix-4.x mips-sgi-irix4 or iris4
1743 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1744 Z8000 simulator z8k-zilog-none or z8ksim
1745 Matsushita MN10200 w/simulator mn10200-*-*
1746 H8/500 simulator h8500-hitachi-hms or h8500hms
1747 HP/PA running BSD hppa*-*-bsd*
1748 HP/PA running OSF/1 hppa*-*-osf*
1749 HP/PA Pro target hppa*-*-pro*
1750 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1751 386BSD i[3456]86-*-bsd*
1752 Sequent family i[3456]86-sequent-sysv4*
1753 i[3456]86-sequent-sysv*
1754 i[3456]86-sequent-bsd*
1755 SPARC running LynxOS sparc-*-lynxos*
1756 SPARC running SunOS 4 sparc-*-sunos4*
1757 Tsqware Sparclet sparclet-*-*
1758 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1760 *** Changes in GDB 6.0:
1764 Support for debugging the Objective-C programming language has been
1765 integrated into GDB.
1767 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1769 DWARF 2's Call Frame Information makes available compiler generated
1770 information that more exactly describes the program's run-time stack.
1771 By using this information, GDB is able to provide more robust stack
1774 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1775 have been updated to use a new backtrace mechanism which includes
1776 DWARF 2 CFI support.
1780 GDB's remote protocol has been extended to include support for hosted
1781 file I/O (where the remote target uses GDB's file system). See GDB's
1782 remote protocol documentation for details.
1784 * All targets using the new architecture framework.
1786 All of GDB's targets have been updated to use the new internal
1787 architecture framework. The way is now open for future GDB releases
1788 to include cross-architecture native debugging support (i386 on amd64,
1791 * GNU/Linux's Thread Local Storage (TLS)
1793 GDB now includes support for for the GNU/Linux implementation of
1794 per-thread variables.
1796 * GNU/Linux's Native POSIX Thread Library (NPTL)
1798 GDB's thread code has been updated to work with either the new
1799 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1801 * Separate debug info.
1803 GDB, in conjunction with BINUTILS, now supports a mechanism for
1804 automatically loading debug information from a separate file. Instead
1805 of shipping full debug and non-debug versions of system libraries,
1806 system integrators can now instead ship just the stripped libraries
1807 and optional debug files.
1809 * DWARF 2 Location Expressions
1811 DWARF 2 Location Expressions allow the compiler to more completely
1812 describe the location of variables (even in optimized code) to the
1815 GDB now includes preliminary support for location expressions (support
1816 for DW_OP_piece is still missing).
1820 A number of long standing bugs that caused GDB to die while starting a
1821 Java application have been fixed. GDB's Java support is now
1822 considered "useable".
1824 * GNU/Linux support for fork, vfork, and exec.
1826 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1827 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1830 * GDB supports logging output to a file
1832 There are two new commands, "set logging" and "show logging", which can be
1833 used to capture GDB's output to a file.
1835 * The meaning of "detach" has changed for gdbserver
1837 The "detach" command will now resume the application, as documented. To
1838 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1841 * d10v, m68hc11 `regs' command deprecated
1843 The `info registers' command has been updated so that it displays the
1844 registers using a format identical to the old `regs' command.
1848 A new command, "maint set profile on/off", has been added. This command can
1849 be used to enable or disable profiling while running GDB, to profile a
1850 session or a set of commands. In addition there is a new configure switch,
1851 "--enable-profiling", which will cause GDB to be compiled with profiling
1852 data, for more informative profiling results.
1854 * Default MI syntax changed to "mi2".
1856 The default MI (machine interface) syntax, enabled by the command line
1857 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1858 "mi1", can be enabled by specifying the option "-i=mi1".
1860 Support for the original "mi0" syntax (included in GDB 5.0) has been
1863 Fix for gdb/192: removed extraneous space when displaying frame level.
1864 Fix for gdb/672: update changelist is now output in mi list format.
1865 Fix for gdb/702: a -var-assign that updates the value now shows up
1866 in a subsequent -var-update.
1868 * New native configurations.
1870 FreeBSD/amd64 x86_64-*-freebsd*
1872 * Multi-arched targets.
1874 HP/PA HPUX11 hppa*-*-hpux*
1875 Renesas M32R/D w/simulator m32r-*-elf*
1877 * OBSOLETE configurations and files
1879 Configurations that have been declared obsolete in this release have
1880 been commented out. Unless there is activity to revive these
1881 configurations, the next release of GDB will have their sources
1882 permanently REMOVED.
1884 Z8000 simulator z8k-zilog-none or z8ksim
1885 Matsushita MN10200 w/simulator mn10200-*-*
1886 H8/500 simulator h8500-hitachi-hms or h8500hms
1887 HP/PA running BSD hppa*-*-bsd*
1888 HP/PA running OSF/1 hppa*-*-osf*
1889 HP/PA Pro target hppa*-*-pro*
1890 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1891 Sequent family i[3456]86-sequent-sysv4*
1892 i[3456]86-sequent-sysv*
1893 i[3456]86-sequent-bsd*
1894 Tsqware Sparclet sparclet-*-*
1895 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1897 * REMOVED configurations and files
1900 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1901 IBM AIX PS/2 i[3456]86-*-aix
1902 i386 running Mach 3.0 i[3456]86-*-mach3*
1903 i386 running Mach i[3456]86-*-mach*
1904 i386 running OSF/1 i[3456]86-*osf1mk*
1905 HP/Apollo 68k Family m68*-apollo*-sysv*,
1907 m68*-hp-bsd*, m68*-hp-hpux*
1908 Argonaut Risc Chip (ARC) arc-*-*
1909 Mitsubishi D30V d30v-*-*
1910 Fujitsu FR30 fr30-*-elf*
1911 OS/9000 i[34]86-*-os9k
1912 I960 with MON960 i960-*-coff
1914 * MIPS $fp behavior changed
1916 The convenience variable $fp, for the MIPS, now consistently returns
1917 the address of the current frame's base. Previously, depending on the
1918 context, $fp could refer to either $sp or the current frame's base
1919 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1920 The GNU Source-Level Debugger''.
1922 *** Changes in GDB 5.3:
1924 * GNU/Linux shared library multi-threaded performance improved.
1926 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1927 `/proc', in preference to `ptrace' for memory reads. This may result
1928 in an improvement in the start-up time of multi-threaded, shared
1929 library applications when run under GDB. One GDB user writes: ``loads
1930 shared libs like mad''.
1932 * ``gdbserver'' now supports multi-threaded applications on some targets
1934 Support for debugging multi-threaded applications which use
1935 the GNU/Linux LinuxThreads package has been added for
1936 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1937 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1939 * GDB now supports C/C++ preprocessor macros.
1941 GDB now expands preprocessor macro invocations in C/C++ expressions,
1942 and provides various commands for showing macro definitions and how
1945 The new command `macro expand EXPRESSION' expands any macro
1946 invocations in expression, and shows the result.
1948 The new command `show macro MACRO-NAME' shows the definition of the
1949 macro named MACRO-NAME, and where it was defined.
1951 Most compilers don't include information about macros in the debugging
1952 information by default. In GCC 3.1, for example, you need to compile
1953 your program with the options `-gdwarf-2 -g3'. If the macro
1954 information is present in the executable, GDB will read it.
1956 * Multi-arched targets.
1958 DEC Alpha (partial) alpha*-*-*
1959 DEC VAX (partial) vax-*-*
1961 National Semiconductor NS32000 (partial) ns32k-*-*
1962 Motorola 68000 (partial) m68k-*-*
1963 Motorola MCORE mcore-*-*
1967 Fujitsu FRV architecture added by Red Hat frv*-*-*
1970 * New native configurations
1972 Alpha NetBSD alpha*-*-netbsd*
1973 SH NetBSD sh*-*-netbsdelf*
1974 MIPS NetBSD mips*-*-netbsd*
1975 UltraSPARC NetBSD sparc64-*-netbsd*
1977 * OBSOLETE configurations and files
1979 Configurations that have been declared obsolete in this release have
1980 been commented out. Unless there is activity to revive these
1981 configurations, the next release of GDB will have their sources
1982 permanently REMOVED.
1984 Mitsubishi D30V d30v-*-*
1985 OS/9000 i[34]86-*-os9k
1986 IBM AIX PS/2 i[3456]86-*-aix
1987 Fujitsu FR30 fr30-*-elf*
1988 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1989 Argonaut Risc Chip (ARC) arc-*-*
1990 i386 running Mach 3.0 i[3456]86-*-mach3*
1991 i386 running Mach i[3456]86-*-mach*
1992 i386 running OSF/1 i[3456]86-*osf1mk*
1993 HP/Apollo 68k Family m68*-apollo*-sysv*,
1995 m68*-hp-bsd*, m68*-hp-hpux*
1996 I960 with MON960 i960-*-coff
1998 * OBSOLETE languages
2000 CHILL, a Pascal like language used by telecommunications companies.
2002 * REMOVED configurations and files
2004 AMD 29k family via UDI a29k-amd-udi, udi29k
2005 A29K VxWorks a29k-*-vxworks
2006 AMD 29000 embedded, using EBMON a29k-none-none
2007 AMD 29000 embedded with COFF a29k-none-coff
2008 AMD 29000 embedded with a.out a29k-none-aout
2010 testsuite/gdb.hp/gdb.threads-hp/ directory
2012 * New command "set max-user-call-depth <nnn>"
2014 This command allows the user to limit the call depth of user-defined
2015 commands. The default is 1024.
2017 * Changes in FreeBSD/i386 native debugging.
2019 Support for the "generate-core-file" has been added.
2021 * New commands "dump", "append", and "restore".
2023 These commands allow data to be copied from target memory
2024 to a bfd-format or binary file (dump and append), and back
2025 from a file into memory (restore).
2027 * Improved "next/step" support on multi-processor Alpha Tru64.
2029 The previous single-step mechanism could cause unpredictable problems,
2030 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2031 of a software single-step mechanism prevents this.
2033 *** Changes in GDB 5.2.1:
2041 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2042 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2043 Fix, by Joel Brobecker imported from mainline.
2045 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2046 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2047 Fix, by Fred Fish, imported from mainline.
2049 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2050 Surprisingly enough, it works now.
2051 By Michal Ludvig, imported from mainline.
2053 i386 hardware watchpoint support:
2054 avoid misses on second run for some targets.
2055 By Pierre Muller, imported from mainline.
2057 *** Changes in GDB 5.2:
2059 * New command "set trust-readonly-sections on[off]".
2061 This command is a hint that tells gdb that read-only sections
2062 really are read-only (ie. that their contents will not change).
2063 In this mode, gdb will go to the object file rather than the
2064 target to read memory from read-only sections (such as ".text").
2065 This can be a significant performance improvement on some
2066 (notably embedded) targets.
2068 * New command "generate-core-file" (or "gcore").
2070 This new gdb command allows the user to drop a core file of the child
2071 process state at any time. So far it's been implemented only for
2072 GNU/Linux and Solaris, but should be relatively easily ported to other
2073 hosts. Argument is core file name (defaults to core.<pid>).
2075 * New command line option
2077 GDB now accepts --pid or -p followed by a process id.
2079 * Change in command line behavior -- corefiles vs. process ids.
2081 There is a subtle behavior in the way in which GDB handles
2082 command line arguments. The first non-flag argument is always
2083 a program to debug, but the second non-flag argument may either
2084 be a corefile or a process id. Previously, GDB would attempt to
2085 open the second argument as a corefile, and if that failed, would
2086 issue a superfluous error message and then attempt to attach it as
2087 a process. Now, if the second argument begins with a non-digit,
2088 it will be treated as a corefile. If it begins with a digit,
2089 GDB will attempt to attach it as a process, and if no such process
2090 is found, will then attempt to open it as a corefile.
2092 * Changes in ARM configurations.
2094 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2095 configuration is fully multi-arch.
2097 * New native configurations
2099 ARM NetBSD arm*-*-netbsd*
2100 x86 OpenBSD i[3456]86-*-openbsd*
2101 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2102 Sparc64 running FreeBSD sparc64-*-freebsd*
2106 Sanyo XStormy16 xstormy16-elf
2108 * OBSOLETE configurations and files
2110 Configurations that have been declared obsolete in this release have
2111 been commented out. Unless there is activity to revive these
2112 configurations, the next release of GDB will have their sources
2113 permanently REMOVED.
2115 AMD 29k family via UDI a29k-amd-udi, udi29k
2116 A29K VxWorks a29k-*-vxworks
2117 AMD 29000 embedded, using EBMON a29k-none-none
2118 AMD 29000 embedded with COFF a29k-none-coff
2119 AMD 29000 embedded with a.out a29k-none-aout
2121 testsuite/gdb.hp/gdb.threads-hp/ directory
2123 * REMOVED configurations and files
2125 TI TMS320C80 tic80-*-*
2127 PowerPC Solaris powerpcle-*-solaris*
2128 PowerPC Windows NT powerpcle-*-cygwin32
2129 PowerPC Netware powerpc-*-netware*
2130 Harris/CXUX m88k m88*-harris-cxux*
2131 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2132 ns32k-utek-sysv* ns32k-utek-*
2133 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2134 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2135 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2136 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2137 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2139 * Changes to command line processing
2141 The new `--args' feature can be used to specify command-line arguments
2142 for the inferior from gdb's command line.
2144 * Changes to key bindings
2146 There is a new `operate-and-get-next' function bound to `C-o'.
2148 *** Changes in GDB 5.1.1
2150 Fix compile problem on DJGPP.
2152 Fix a problem with floating-point registers on the i386 being
2155 Fix to stop GDB crashing on .debug_str debug info.
2157 Numerous documentation fixes.
2159 Numerous testsuite fixes.
2161 *** Changes in GDB 5.1:
2163 * New native configurations
2165 Alpha FreeBSD alpha*-*-freebsd*
2166 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2167 MIPS GNU/Linux mips*-*-linux*
2168 MIPS SGI Irix 6.x mips*-sgi-irix6*
2169 ia64 AIX ia64-*-aix*
2170 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2174 Motorola 68HC11 and 68HC12 m68hc11-elf
2176 UltraSparc running GNU/Linux sparc64-*-linux*
2178 * OBSOLETE configurations and files
2180 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2181 Harris/CXUX m88k m88*-harris-cxux*
2182 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2183 ns32k-utek-sysv* ns32k-utek-*
2184 TI TMS320C80 tic80-*-*
2186 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2187 PowerPC Solaris powerpcle-*-solaris*
2188 PowerPC Windows NT powerpcle-*-cygwin32
2189 PowerPC Netware powerpc-*-netware*
2190 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2191 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2192 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2193 Apple Macintosh (MPW) host N/A
2195 stuff.c (Program to stuff files into a specially prepared space in kdb)
2196 kdb-start.c (Main loop for the standalone kernel debugger)
2198 Configurations that have been declared obsolete in this release have
2199 been commented out. Unless there is activity to revive these
2200 configurations, the next release of GDB will have their sources
2201 permanently REMOVED.
2203 * REMOVED configurations and files
2205 Altos 3068 m68*-altos-*
2206 Convex c1-*-*, c2-*-*
2208 ARM RISCix arm-*-* (as host)
2212 * GDB has been converted to ISO C.
2214 GDB's source code has been converted to ISO C. In particular, the
2215 sources are fully protoized, and rely on standard headers being
2220 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2222 * The MI enabled by default.
2224 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2225 revised and enabled by default. Packages which use GDB as a debugging
2226 engine behind a UI or another front end are encouraged to switch to
2227 using the GDB/MI interface, instead of the old annotations interface
2228 which is now deprecated.
2230 * Support for debugging Pascal programs.
2232 GDB now includes support for debugging Pascal programs. The following
2233 main features are supported:
2235 - Pascal-specific data types such as sets;
2237 - automatic recognition of Pascal sources based on file-name
2240 - Pascal-style display of data types, variables, and functions;
2242 - a Pascal expression parser.
2244 However, some important features are not yet supported.
2246 - Pascal string operations are not supported at all;
2248 - there are some problems with boolean types;
2250 - Pascal type hexadecimal constants are not supported
2251 because they conflict with the internal variables format;
2253 - support for Pascal objects and classes is not full yet;
2255 - unlike Pascal, GDB is case-sensitive for symbol names.
2257 * Changes in completion.
2259 Commands such as `shell', `run' and `set args', which pass arguments
2260 to inferior programs, now complete on file names, similar to what
2261 users expect at the shell prompt.
2263 Commands which accept locations, such as `disassemble', `print',
2264 `breakpoint', `until', etc. now complete on filenames as well as
2265 program symbols. Thus, if you type "break foob TAB", and the source
2266 files linked into the programs include `foobar.c', that file name will
2267 be one of the candidates for completion. However, file names are not
2268 considered for completion after you typed a colon that delimits a file
2269 name from a name of a function in that file, as in "break foo.c:bar".
2271 `set demangle-style' completes on available demangling styles.
2273 * New platform-independent commands:
2275 It is now possible to define a post-hook for a command as well as a
2276 hook that runs before the command. For more details, see the
2277 documentation of `hookpost' in the GDB manual.
2279 * Changes in GNU/Linux native debugging.
2281 Support for debugging multi-threaded programs has been completely
2282 revised for all platforms except m68k and sparc. You can now debug as
2283 many threads as your system allows you to have.
2285 Attach/detach is supported for multi-threaded programs.
2287 Support for SSE registers was added for x86. This doesn't work for
2288 multi-threaded programs though.
2290 * Changes in MIPS configurations.
2292 Multi-arch support is enabled for all MIPS configurations.
2294 GDB can now be built as native debugger on SGI Irix 6.x systems for
2295 debugging n32 executables. (Debugging 64-bit executables is not yet
2298 * Unified support for hardware watchpoints in all x86 configurations.
2300 Most (if not all) native x86 configurations support hardware-assisted
2301 breakpoints and watchpoints in a unified manner. This support
2302 implements debug register sharing between watchpoints, which allows to
2303 put a virtually infinite number of watchpoints on the same address,
2304 and also supports watching regions up to 16 bytes with several debug
2307 The new maintenance command `maintenance show-debug-regs' toggles
2308 debugging print-outs in functions that insert, remove, and test
2309 watchpoints and hardware breakpoints.
2311 * Changes in the DJGPP native configuration.
2313 New command ``info dos sysinfo'' displays assorted information about
2314 the CPU, OS, memory, and DPMI server.
2316 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2317 display information about segment descriptors stored in GDT, LDT, and
2320 New commands ``info dos pde'' and ``info dos pte'' display entries
2321 from Page Directory and Page Tables (for now works with CWSDPMI only).
2322 New command ``info dos address-pte'' displays the Page Table entry for
2323 a given linear address.
2325 GDB can now pass command lines longer than 126 characters to the
2326 program being debugged (requires an update to the libdbg.a library
2327 which is part of the DJGPP development kit).
2329 DWARF2 debug info is now supported.
2331 It is now possible to `step' and `next' through calls to `longjmp'.
2333 * Changes in documentation.
2335 All GDB documentation was converted to GFDL, the GNU Free
2336 Documentation License.
2338 Tracepoints-related commands are now fully documented in the GDB
2341 TUI, the Text-mode User Interface, is now documented in the manual.
2343 Tracepoints-related commands are now fully documented in the GDB
2346 The "GDB Internals" manual now has an index. It also includes
2347 documentation of `ui_out' functions, GDB coding standards, x86
2348 hardware watchpoints, and memory region attributes.
2350 * GDB's version number moved to ``version.in''
2352 The Makefile variable VERSION has been replaced by the file
2353 ``version.in''. People creating GDB distributions should update the
2354 contents of this file.
2358 GUD support is now a standard part of the EMACS distribution.
2360 *** Changes in GDB 5.0:
2362 * Improved support for debugging FP programs on x86 targets
2364 Unified and much-improved support for debugging floating-point
2365 programs on all x86 targets. In particular, ``info float'' now
2366 displays the FP registers in the same format on all x86 targets, with
2367 greater level of detail.
2369 * Improvements and bugfixes in hardware-assisted watchpoints
2371 It is now possible to watch array elements, struct members, and
2372 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2373 on x86 targets no longer erroneously trigger when the address is
2376 * Improvements in the native DJGPP version of GDB
2378 The distribution now includes all the scripts and auxiliary files
2379 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2380 machines ``out of the box''.
2382 The DJGPP version can now debug programs that use signals. It is
2383 possible to catch signals that happened in the debuggee, deliver
2384 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2385 would kill the program being debugged.) Programs that hook hardware
2386 interrupts (keyboard, timer, etc.) can also be debugged.
2388 It is now possible to debug DJGPP programs that redirect their
2389 standard handles or switch them to raw (as opposed to cooked) mode, or
2390 even close them. The command ``run < foo > bar'' works as expected,
2391 and ``info terminal'' reports useful information about the debuggee's
2392 terminal, including raw/cooked mode, redirection, etc.
2394 The DJGPP version now uses termios functions for console I/O, which
2395 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2398 DOS-style file names with drive letters are now fully supported by
2401 It is now possible to debug DJGPP programs that switch their working
2402 directory. It is also possible to rerun the debuggee any number of
2403 times without restarting GDB; thus, you can use the same setup,
2404 breakpoints, etc. for many debugging sessions.
2406 * New native configurations
2408 ARM GNU/Linux arm*-*-linux*
2409 PowerPC GNU/Linux powerpc-*-linux*
2413 Motorola MCore mcore-*-*
2414 x86 VxWorks i[3456]86-*-vxworks*
2415 PowerPC VxWorks powerpc-*-vxworks*
2416 TI TMS320C80 tic80-*-*
2418 * OBSOLETE configurations
2420 Altos 3068 m68*-altos-*
2421 Convex c1-*-*, c2-*-*
2423 ARM RISCix arm-*-* (as host)
2426 Configurations that have been declared obsolete will be commented out,
2427 but the code will be left in place. If there is no activity to revive
2428 these configurations before the next release of GDB, the sources will
2429 be permanently REMOVED.
2431 * Gould support removed
2433 Support for the Gould PowerNode and NP1 has been removed.
2435 * New features for SVR4
2437 On SVR4 native platforms (such as Solaris), if you attach to a process
2438 without first loading a symbol file, GDB will now attempt to locate and
2439 load symbols from the running process's executable file.
2441 * Many C++ enhancements
2443 C++ support has been greatly improved. Overload resolution now works properly
2444 in almost all cases. RTTI support is on the way.
2446 * Remote targets can connect to a sub-program
2448 A popen(3) style serial-device has been added. This device starts a
2449 sub-process (such as a stand-alone simulator) and then communicates
2450 with that. The sub-program to run is specified using the syntax
2451 ``|<program> <args>'' vis:
2453 (gdb) set remotedebug 1
2454 (gdb) target extended-remote |mn10300-elf-sim program-args
2456 * MIPS 64 remote protocol
2458 A long standing bug in the mips64 remote protocol where by GDB
2459 expected certain 32 bit registers (ex SR) to be transfered as 32
2460 instead of 64 bits has been fixed.
2462 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2463 added to provide backward compatibility with older versions of GDB.
2465 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2467 The command ``set remotebinarydownload'' command has been replaced by
2468 ``set remote X-packet''. Other commands in ``set remote'' family
2469 include ``set remote P-packet''.
2471 * Breakpoint commands accept ranges.
2473 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2474 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2475 ``tracepoint passcount'' also accepts a range of tracepoints.
2477 * ``apropos'' command added.
2479 The ``apropos'' command searches through command names and
2480 documentation strings, printing out matches, making it much easier to
2481 try to find a command that does what you are looking for.
2485 A new machine oriented interface (MI) has been added to GDB. This
2486 interface is designed for debug environments running GDB as a separate
2487 process. This is part of the long term libGDB project. See the
2488 "GDB/MI" chapter of the GDB manual for further information. It can be
2489 enabled by configuring with:
2491 .../configure --enable-gdbmi
2493 *** Changes in GDB-4.18:
2495 * New native configurations
2497 HP-UX 10.20 hppa*-*-hpux10.20
2498 HP-UX 11.x hppa*-*-hpux11.0*
2499 M68K GNU/Linux m68*-*-linux*
2503 Fujitsu FR30 fr30-*-elf*
2504 Intel StrongARM strongarm-*-*
2505 Mitsubishi D30V d30v-*-*
2507 * OBSOLETE configurations
2509 Gould PowerNode, NP1 np1-*-*, pn-*-*
2511 Configurations that have been declared obsolete will be commented out,
2512 but the code will be left in place. If there is no activity to revive
2513 these configurations before the next release of GDB, the sources will
2514 be permanently REMOVED.
2518 As a compatibility experiment, GDB's source files buildsym.h and
2519 buildsym.c have been converted to pure standard C, no longer
2520 containing any K&R compatibility code. We believe that all systems in
2521 use today either come with a standard C compiler, or have a GCC port
2522 available. If this is not true, please report the affected
2523 configuration to bug-gdb@gnu.org immediately. See the README file for
2524 information about getting a standard C compiler if you don't have one
2529 GDB now uses readline 2.2.
2531 * set extension-language
2533 You can now control the mapping between filename extensions and source
2534 languages by using the `set extension-language' command. For instance,
2535 you can ask GDB to treat .c files as C++ by saying
2536 set extension-language .c c++
2537 The command `info extensions' lists all of the recognized extensions
2538 and their associated languages.
2540 * Setting processor type for PowerPC and RS/6000
2542 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2543 you can use the `set processor' command to specify what variant of the
2544 PowerPC family you are debugging. The command
2548 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2549 following PowerPC and RS6000 variants:
2551 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2552 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2554 403GC IBM PowerPC 403GC
2555 505 Motorola PowerPC 505
2556 860 Motorola PowerPC 860 or 850
2557 601 Motorola PowerPC 601
2558 602 Motorola PowerPC 602
2559 603 Motorola/IBM PowerPC 603 or 603e
2560 604 Motorola PowerPC 604 or 604e
2561 750 Motorola/IBM PowerPC 750 or 750
2563 At the moment, this command just tells GDB what to name the
2564 special-purpose processor registers. Since almost all the affected
2565 registers are inaccessible to user-level programs, this command is
2566 only useful for remote debugging in its present form.
2570 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2571 more extensive support for HP-UX. Added features include shared
2572 library support, kernel threads and hardware watchpoints for 11.00,
2573 support for HP's ANSI C and C++ compilers, and a compatibility mode
2574 for xdb and dbx commands.
2578 HP's donation includes the new concept of catchpoints, which is a
2579 generalization of the old catch command. On HP-UX, it is now possible
2580 to catch exec, fork, and vfork, as well as library loading.
2582 This means that the existing catch command has changed; its first
2583 argument now specifies the type of catch to be set up. See the
2584 output of "help catch" for a list of catchpoint types.
2586 * Debugging across forks
2588 On HP-UX, you can choose which process to debug when a fork() happens
2593 HP has donated a curses-based terminal user interface (TUI). To get
2594 it, build with --enable-tui. Although this can be enabled for any
2595 configuration, at present it only works for native HP debugging.
2597 * GDB remote protocol additions
2599 A new protocol packet 'X' that writes binary data is now available.
2600 Default behavior is to try 'X', then drop back to 'M' if the stub
2601 fails to respond. The settable variable `remotebinarydownload'
2602 allows explicit control over the use of 'X'.
2604 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2605 full 64-bit address. The command
2607 set remoteaddresssize 32
2609 can be used to revert to the old behaviour. For existing remote stubs
2610 the change should not be noticed, as the additional address information
2613 In order to assist in debugging stubs, you may use the maintenance
2614 command `packet' to send any text string to the stub. For instance,
2616 maint packet heythere
2618 sends the packet "$heythere#<checksum>". Note that it is very easy to
2619 disrupt a debugging session by sending the wrong packet at the wrong
2622 The compare-sections command allows you to compare section data on the
2623 target to what is in the executable file without uploading or
2624 downloading, by comparing CRC checksums.
2626 * Tracing can collect general expressions
2628 You may now collect general expressions at tracepoints. This requires
2629 further additions to the target-side stub; see tracepoint.c and
2630 doc/agentexpr.texi for further details.
2632 * mask-address variable for Mips
2634 For Mips targets, you may control the zeroing of the upper 32 bits of
2635 a 64-bit address by entering `set mask-address on'. This is mainly
2636 of interest to users of embedded R4xxx and R5xxx processors.
2638 * Higher serial baud rates
2640 GDB's serial code now allows you to specify baud rates 57600, 115200,
2641 230400, and 460800 baud. (Note that your host system may not be able
2642 to achieve all of these rates.)
2646 The i960 configuration now includes an initial implementation of a
2647 builtin simulator, contributed by Jim Wilson.
2650 *** Changes in GDB-4.17:
2652 * New native configurations
2654 Alpha GNU/Linux alpha*-*-linux*
2655 Unixware 2.x i[3456]86-unixware2*
2656 Irix 6.x mips*-sgi-irix6*
2657 PowerPC GNU/Linux powerpc-*-linux*
2658 PowerPC Solaris powerpcle-*-solaris*
2659 Sparc GNU/Linux sparc-*-linux*
2660 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2664 Argonaut Risc Chip (ARC) arc-*-*
2665 Hitachi H8/300S h8300*-*-*
2666 Matsushita MN10200 w/simulator mn10200-*-*
2667 Matsushita MN10300 w/simulator mn10300-*-*
2668 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2669 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2670 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2671 Mitsubishi D10V w/simulator d10v-*-*
2672 Mitsubishi M32R/D w/simulator m32r-*-elf*
2673 Tsqware Sparclet sparclet-*-*
2674 NEC V850 w/simulator v850-*-*
2676 * New debugging protocols
2678 ARM with RDI protocol arm*-*-*
2679 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2680 DDB and LSI variants of PMON protocol mips*-*-*
2681 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2682 PowerPC with SDS protocol powerpc{,le}-*-eabi
2683 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2687 All configurations can now understand and use the DWARF 2 debugging
2688 format. The choice is automatic, if the symbol file contains DWARF 2
2693 GDB now includes basic Java language support. This support is
2694 only useful with Java compilers that produce native machine code.
2696 * solib-absolute-prefix and solib-search-path
2698 For SunOS and SVR4 shared libraries, you may now set the prefix for
2699 loading absolute shared library symbol files, and the search path for
2700 locating non-absolute shared library symbol files.
2702 * Live range splitting
2704 GDB can now effectively debug code for which GCC has performed live
2705 range splitting as part of its optimization. See gdb/doc/LRS for
2706 more details on the expected format of the stabs information.
2710 GDB's support for the GNU Hurd, including thread debugging, has been
2711 updated to work with current versions of the Hurd.
2715 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2716 instruction set. ARM GDB automatically detects when Thumb
2717 instructions are in use, and adjusts disassembly and backtracing
2722 GDB's MIPS target configurations now handle the MIP16 16-bit
2727 GDB now includes support for overlays; if an executable has been
2728 linked such that multiple sections are based at the same address, GDB
2729 will decide which section to use for symbolic info. You can choose to
2730 control the decision manually, using overlay commands, or implement
2731 additional target-side support and use "overlay load-target" to bring
2732 in the overlay mapping. Do "help overlay" for more detail.
2736 The command "info symbol <address>" displays information about
2737 the symbol at the specified address.
2741 The standard remote protocol now includes an extension that allows
2742 asynchronous collection and display of trace data. This requires
2743 extensive support in the target-side debugging stub. Tracing mode
2744 includes a new interaction mode in GDB and new commands: see the
2745 file tracepoint.c for more details.
2749 Configurations for embedded MIPS now include a simulator contributed
2750 by Cygnus Solutions. The simulator supports the instruction sets
2751 of most MIPS variants.
2755 Sparc configurations may now include the ERC32 simulator contributed
2756 by the European Space Agency. The simulator is not built into
2757 Sparc targets by default; configure with --enable-sim to include it.
2761 For target configurations that may include multiple variants of a
2762 basic architecture (such as MIPS and SH), you may now set the
2763 architecture explicitly. "set arch" sets, "info arch" lists
2764 the possible architectures.
2766 *** Changes in GDB-4.16:
2768 * New native configurations
2770 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2771 M68K NetBSD m68k-*-netbsd*
2772 PowerPC AIX 4.x powerpc-*-aix*
2773 PowerPC MacOS powerpc-*-macos*
2774 PowerPC Windows NT powerpcle-*-cygwin32
2775 RS/6000 AIX 4.x rs6000-*-aix4*
2779 ARM with RDP protocol arm-*-*
2780 I960 with MON960 i960-*-coff
2781 MIPS VxWorks mips*-*-vxworks*
2782 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2783 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2785 Matra Sparclet sparclet-*-*
2789 The powerpc-eabi configuration now includes the PSIM simulator,
2790 contributed by Andrew Cagney, with assistance from Mike Meissner.
2791 PSIM is a very elaborate model of the PowerPC, including not only
2792 basic instruction set execution, but also details of execution unit
2793 performance and I/O hardware. See sim/ppc/README for more details.
2797 GDB now works with Solaris 2.5.
2799 * Windows 95/NT native
2801 GDB will now work as a native debugger on Windows 95 and Windows NT.
2802 To build it from source, you must use the "gnu-win32" environment,
2803 which uses a DLL to emulate enough of Unix to run the GNU tools.
2804 Further information, binaries, and sources are available at
2805 ftp.cygnus.com, under pub/gnu-win32.
2807 * dont-repeat command
2809 If a user-defined command includes the command `dont-repeat', then the
2810 command will not be repeated if the user just types return. This is
2811 useful if the command is time-consuming to run, so that accidental
2812 extra keystrokes don't run the same command many times.
2814 * Send break instead of ^C
2816 The standard remote protocol now includes an option to send a break
2817 rather than a ^C to the target in order to interrupt it. By default,
2818 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2820 * Remote protocol timeout
2822 The standard remote protocol includes a new variable `remotetimeout'
2823 that allows you to set the number of seconds before GDB gives up trying
2824 to read from the target. The default value is 2.
2826 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2828 By default GDB will automatically keep track of objects as they are
2829 loaded and unloaded by the dynamic linker. By using the command `set
2830 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2831 when shared library events occur, thus allowing you to set breakpoints
2832 in shared libraries which are explicitly loaded by the inferior.
2834 Note this feature does not work on hpux8. On hpux9 you must link
2835 /usr/lib/end.o into your program. This feature should work
2836 automatically on hpux10.
2838 * Irix 5.x hardware watchpoint support
2840 Irix 5 configurations now support the use of hardware watchpoints.
2842 * Mips protocol "SYN garbage limit"
2844 When debugging a Mips target using the `target mips' protocol, you
2845 may set the number of characters that GDB will ignore by setting
2846 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2847 every character. The default value is 1050.
2849 * Recording and replaying remote debug sessions
2851 If you set `remotelogfile' to the name of a file, gdb will write to it
2852 a recording of a remote debug session. This recording may then be
2853 replayed back to gdb using "gdbreplay". See gdbserver/README for
2854 details. This is useful when you have a problem with GDB while doing
2855 remote debugging; you can make a recording of the session and send it
2856 to someone else, who can then recreate the problem.
2858 * Speedups for remote debugging
2860 GDB includes speedups for downloading and stepping MIPS systems using
2861 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2862 and more efficient S-record downloading.
2864 * Memory use reductions and statistics collection
2866 GDB now uses less memory and reports statistics about memory usage.
2867 Try the `maint print statistics' command, for example.
2869 *** Changes in GDB-4.15:
2871 * Psymtabs for XCOFF
2873 The symbol reader for AIX GDB now uses partial symbol tables. This
2874 can greatly improve startup time, especially for large executables.
2876 * Remote targets use caching
2878 Remote targets now use a data cache to speed up communication with the
2879 remote side. The data cache could lead to incorrect results because
2880 it doesn't know about volatile variables, thus making it impossible to
2881 debug targets which use memory mapped I/O devices. `set remotecache
2882 off' turns the the data cache off.
2884 * Remote targets may have threads
2886 The standard remote protocol now includes support for multiple threads
2887 in the target system, using new protocol commands 'H' and 'T'. See
2888 gdb/remote.c for details.
2892 If GDB is configured with `--enable-netrom', then it will include
2893 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2894 acts as though it is a bank of ROM on the target board, but you can
2895 write into it over the network. GDB's support consists only of
2896 support for fast loading into the emulated ROM; to debug, you must use
2897 another protocol, such as standard remote protocol. The usual
2898 sequence is something like
2900 target nrom <netrom-hostname>
2902 target remote <netrom-hostname>:1235
2906 GDB now includes support for the Apple Macintosh, as a host only. It
2907 may be run as either an MPW tool or as a standalone application, and
2908 it can debug through the serial port. All the usual GDB commands are
2909 available, but to the target command, you must supply "serial" as the
2910 device type instead of "/dev/ttyXX". See mpw-README in the main
2911 directory for more information on how to build. The MPW configuration
2912 scripts */mpw-config.in support only a few targets, and only the
2913 mips-idt-ecoff target has been tested.
2917 GDB configuration now uses autoconf. This is not user-visible,
2918 but does simplify configuration and building.
2922 GDB now supports hpux10.
2924 *** Changes in GDB-4.14:
2926 * New native configurations
2928 x86 FreeBSD i[345]86-*-freebsd
2929 x86 NetBSD i[345]86-*-netbsd
2930 NS32k NetBSD ns32k-*-netbsd
2931 Sparc NetBSD sparc-*-netbsd
2935 A29K VxWorks a29k-*-vxworks
2936 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2937 CPU32 EST-300 emulator m68*-*-est*
2938 PowerPC ELF powerpc-*-elf
2941 * Alpha OSF/1 support for procfs
2943 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2944 possible to attach to running processes. As the mounting of the /proc
2945 filesystem is optional on the Alpha, GDB automatically determines
2946 the availability of /proc during startup. This can lead to problems
2947 if /proc is unmounted after GDB has been started.
2949 * Arguments to user-defined commands
2951 User commands may accept up to 10 arguments separated by whitespace.
2952 Arguments are accessed within the user command via $arg0..$arg9. A
2955 print $arg0 + $arg1 + $arg2
2957 To execute the command use:
2960 Defines the command "adder" which prints the sum of its three arguments.
2961 Note the arguments are text substitutions, so they may reference variables,
2962 use complex expressions, or even perform inferior function calls.
2964 * New `if' and `while' commands
2966 This makes it possible to write more sophisticated user-defined
2967 commands. Both commands take a single argument, which is the
2968 expression to evaluate, and must be followed by the commands to
2969 execute, one per line, if the expression is nonzero, the list being
2970 terminated by the word `end'. The `if' command list may include an
2971 `else' word, which causes the following commands to be executed only
2972 if the expression is zero.
2974 * Fortran source language mode
2976 GDB now includes partial support for Fortran 77. It will recognize
2977 Fortran programs and can evaluate a subset of Fortran expressions, but
2978 variables and functions may not be handled correctly. GDB will work
2979 with G77, but does not yet know much about symbols emitted by other
2982 * Better HPUX support
2984 Most debugging facilities now work on dynamic executables for HPPAs
2985 running hpux9 or later. You can attach to running dynamically linked
2986 processes, but by default the dynamic libraries will be read-only, so
2987 for instance you won't be able to put breakpoints in them. To change
2988 that behavior do the following before running the program:
2994 This will cause the libraries to be mapped private and read-write.
2995 To revert to the normal behavior, do this:
3001 You cannot set breakpoints or examine data in the library until after
3002 the library is loaded if the function/data symbols do not have
3005 GDB can now also read debug symbols produced by the HP C compiler on
3006 HPPAs (sorry, no C++, Fortran or 68k support).
3008 * Target byte order now dynamically selectable
3010 You can choose which byte order to use with a target system, via the
3011 commands "set endian big" and "set endian little", and you can see the
3012 current setting by using "show endian". You can also give the command
3013 "set endian auto", in which case GDB will use the byte order
3014 associated with the executable. Currently, only embedded MIPS
3015 configurations support dynamic selection of target byte order.
3017 * New DOS host serial code
3019 This version uses DPMI interrupts to handle buffered I/O, so you
3020 no longer need to run asynctsr when debugging boards connected to
3023 *** Changes in GDB-4.13:
3025 * New "complete" command
3027 This lists all the possible completions for the rest of the line, if it
3028 were to be given as a command itself. This is intended for use by emacs.
3030 * Trailing space optional in prompt
3032 "set prompt" no longer adds a space for you after the prompt you set. This
3033 allows you to set a prompt which ends in a space or one that does not.
3035 * Breakpoint hit counts
3037 "info break" now displays a count of the number of times the breakpoint
3038 has been hit. This is especially useful in conjunction with "ignore"; you
3039 can ignore a large number of breakpoint hits, look at the breakpoint info
3040 to see how many times the breakpoint was hit, then run again, ignoring one
3041 less than that number, and this will get you quickly to the last hit of
3044 * Ability to stop printing at NULL character
3046 "set print null-stop" will cause GDB to stop printing the characters of
3047 an array when the first NULL is encountered. This is useful when large
3048 arrays actually contain only short strings.
3050 * Shared library breakpoints
3052 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3053 breakpoints in shared libraries before the executable is run.
3055 * Hardware watchpoints
3057 There is a new hardware breakpoint for the watch command for sparclite
3058 targets. See gdb/sparclite/hw_breakpoint.note.
3060 Hardware watchpoints are also now supported under GNU/Linux.
3064 Annotations have been added. These are for use with graphical interfaces,
3065 and are still experimental. Currently only gdba.el uses these.
3067 * Improved Irix 5 support
3069 GDB now works properly with Irix 5.2.
3071 * Improved HPPA support
3073 GDB now works properly with the latest GCC and GAS.
3075 * New native configurations
3077 Sequent PTX4 i[34]86-sequent-ptx4
3078 HPPA running OSF/1 hppa*-*-osf*
3079 Atari TT running SVR4 m68*-*-sysv4*
3080 RS/6000 LynxOS rs6000-*-lynxos*
3084 OS/9000 i[34]86-*-os9k
3085 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3088 * Hitachi SH7000 and E7000-PC ICE support
3090 There is now support for communicating with the Hitachi E7000-PC ICE.
3091 This is available automatically when GDB is configured for the SH.
3095 As usual, a variety of small fixes and improvements, both generic
3096 and configuration-specific. See the ChangeLog for more detail.
3098 *** Changes in GDB-4.12:
3100 * Irix 5 is now supported
3104 GDB-4.12 on the HPPA has a number of changes which make it unable
3105 to debug the output from the currently released versions of GCC and
3106 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3107 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3108 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3111 *** Changes in GDB-4.11:
3113 * User visible changes:
3117 The "set remotedebug" option is now consistent between the mips remote
3118 target, remote targets using the gdb-specific protocol, UDI (AMD's
3119 debug protocol for the 29k) and the 88k bug monitor. It is now an
3120 integer specifying a debug level (normally 0 or 1, but 2 means more
3121 debugging info for the mips target).
3123 * DEC Alpha native support
3125 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3126 debug info, but GDB works fairly well with the DEC compiler and should
3127 work with a future GCC release. See the README file for a few
3128 Alpha-specific notes.
3130 * Preliminary thread implementation
3132 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3134 * LynxOS native and target support for 386
3136 This release has been hosted on LynxOS 2.2, and also can be configured
3137 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3140 * Improvements in C++ mangling/demangling.
3142 This release has much better g++ debugging, specifically in name
3143 mangling/demangling, virtual function calls, print virtual table,
3144 call methods, ...etc.
3146 *** Changes in GDB-4.10:
3148 * User visible changes:
3150 Remote debugging using the GDB-specific (`target remote') protocol now
3151 supports the `load' command. This is only useful if you have some
3152 other way of getting the stub to the target system, and you can put it
3153 somewhere in memory where it won't get clobbered by the download.
3155 Filename completion now works.
3157 When run under emacs mode, the "info line" command now causes the
3158 arrow to point to the line specified. Also, "info line" prints
3159 addresses in symbolic form (as well as hex).
3161 All vxworks based targets now support a user settable option, called
3162 vxworks-timeout. This option represents the number of seconds gdb
3163 should wait for responses to rpc's. You might want to use this if
3164 your vxworks target is, perhaps, a slow software simulator or happens
3165 to be on the far side of a thin network line.
3169 This release contains support for using a DEC alpha as a GDB host for
3170 cross debugging. Native alpha debugging is not supported yet.
3173 *** Changes in GDB-4.9:
3177 This is the first GDB release which is accompanied by a matching testsuite.
3178 The testsuite requires installation of dejagnu, which should be available
3179 via ftp from most sites that carry GNU software.
3183 'Cfront' style demangling has had its name changed to 'ARM' style, to
3184 emphasize that it was written from the specifications in the C++ Annotated
3185 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3186 disclaimers, it still generated too much confusion with users attempting to
3187 use gdb with AT&T cfront.
3191 GDB now uses a standard remote interface to a simulator library.
3192 So far, the library contains simulators for the Zilog Z8001/2, the
3193 Hitachi H8/300, H8/500 and Super-H.
3195 * New targets supported
3197 H8/300 simulator h8300-hitachi-hms or h8300hms
3198 H8/500 simulator h8500-hitachi-hms or h8500hms
3199 SH simulator sh-hitachi-hms or sh
3200 Z8000 simulator z8k-zilog-none or z8ksim
3201 IDT MIPS board over serial line mips-idt-ecoff
3203 Cross-debugging to GO32 targets is supported. It requires a custom
3204 version of the i386-stub.c module which is integrated with the
3205 GO32 memory extender.
3207 * New remote protocols
3209 MIPS remote debugging protocol.
3211 * New source languages supported
3213 This version includes preliminary support for Chill, a Pascal like language
3214 used by telecommunications companies. Chill support is also being integrated
3215 into the GNU compiler, but we don't know when it will be publically available.
3218 *** Changes in GDB-4.8:
3220 * HP Precision Architecture supported
3222 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3223 version of this support was available as a set of patches from the
3224 University of Utah. GDB does not support debugging of programs
3225 compiled with the HP compiler, because HP will not document their file
3226 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3227 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3229 Many problems in the preliminary version have been fixed.
3231 * Faster and better demangling
3233 We have improved template demangling and fixed numerous bugs in the GNU style
3234 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3235 character types (wchar_t) are now supported. Demangling of each symbol is now
3236 only done once, and is cached when the symbol table for a file is read in.
3237 This results in a small increase in memory usage for C programs, a moderate
3238 increase in memory usage for C++ programs, and a fantastic speedup in
3241 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3242 from the specifications in the Annotated Reference Manual, which AT&T's
3243 compiler does not actually implement.
3245 * G++ multiple inheritance compiler problem
3247 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3248 inheritance lattices was reworked to properly discover ambiguities. We
3249 recently found an example which causes this new algorithm to fail in a
3250 very subtle way, producing bad debug information for those classes.
3251 The file 'gcc.patch' (in this directory) can be applied to gcc to
3252 circumvent the problem. A future GCC release will contain a complete
3255 The previous G++ debug info problem (mentioned below for the gdb-4.7
3256 release) is fixed in gcc version 2.3.2.
3258 * Improved configure script
3260 The `configure' script will now attempt to guess your system type if
3261 you don't supply a host system type. The old scheme of supplying a
3262 host system triplet is preferable over using this. All the magic is
3263 done in the new `config.guess' script. Examine it for details.
3265 We have also brought our configure script much more in line with the FSF's
3266 version. It now supports the --with-xxx options. In particular,
3267 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3268 The resulting GDB will not be able to read arbitrary object file formats --
3269 only the format ``expected'' to be used on the configured target system.
3270 We hope to make this the default in a future release.
3272 * Documentation improvements
3274 There's new internal documentation on how to modify GDB, and how to
3275 produce clean changes to the code. We implore people to read it
3276 before submitting changes.
3278 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3279 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3280 `info' files are also provided. To build `info' files from scratch,
3281 you will need the latest `makeinfo' release, which will be available in
3282 a future texinfo-X.Y release.
3284 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3285 We're not sure exactly which versions have this problem, but it has
3286 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3287 or better. If that isn't possible, there is a patch in
3288 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3289 around this problem.
3293 GDB now supports array constants that can be used in expressions typed in by
3294 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3295 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3298 The new directory `gdb/sparclite' contains a program that demonstrates
3299 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3301 * New native hosts supported
3303 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3304 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3306 * New targets supported
3308 AMD 29k family via UDI a29k-amd-udi or udi29k
3310 * New file formats supported
3312 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3313 HPUX core files, and SCO 3.2v2 core files.
3317 Attaching to processes now works again; thanks for the many bug reports.
3319 We have also stomped on a bunch of core dumps caused by
3320 printf_filtered("%s") problems.
3322 We eliminated a copyright problem on the rpc and ptrace header files
3323 for VxWorks, which was discovered at the last minute during the 4.7
3324 release. You should now be able to build a VxWorks GDB.
3326 You can now interrupt gdb while an attached process is running. This
3327 will cause the attached process to stop, and give control back to GDB.
3329 We fixed problems caused by using too many file descriptors
3330 for reading symbols from object files and libraries. This was
3331 especially a problem for programs that used many (~100) shared
3334 The `step' command now only enters a subroutine if there is line number
3335 information for the subroutine. Otherwise it acts like the `next'
3336 command. Previously, `step' would enter subroutines if there was
3337 any debugging information about the routine. This avoids problems
3338 when using `cc -g1' on MIPS machines.
3340 * Internal improvements
3342 GDB's internal interfaces have been improved to make it easier to support
3343 debugging of multiple languages in the future.
3345 GDB now uses a common structure for symbol information internally.
3346 Minimal symbols (derived from linkage symbols in object files), partial
3347 symbols (from a quick scan of debug information), and full symbols
3348 contain a common subset of information, making it easier to write
3349 shared code that handles any of them.
3351 * New command line options
3353 We now accept --silent as an alias for --quiet.
3357 The memory-mapped-malloc library is now licensed under the GNU Library
3358 General Public License.
3360 *** Changes in GDB-4.7:
3362 * Host/native/target split
3364 GDB has had some major internal surgery to untangle the support for
3365 hosts and remote targets. Now, when you configure GDB for a remote
3366 target, it will no longer load in all of the support for debugging
3367 local programs on the host. When fully completed and tested, this will
3368 ensure that arbitrary host/target combinations are possible.
3370 The primary conceptual shift is to separate the non-portable code in
3371 GDB into three categories. Host specific code is required any time GDB
3372 is compiled on that host, regardless of the target. Target specific
3373 code relates to the peculiarities of the target, but can be compiled on
3374 any host. Native specific code is everything else: it can only be
3375 built when the host and target are the same system. Child process
3376 handling and core file support are two common `native' examples.
3378 GDB's use of /proc for controlling Unix child processes is now cleaner.
3379 It has been split out into a single module under the `target_ops' vector,
3380 plus two native-dependent functions for each system that uses /proc.
3382 * New hosts supported
3384 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3385 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3386 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3388 * New targets supported
3390 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3391 68030 and CPU32 m68030-*-*, m68332-*-*
3393 * New native hosts supported
3395 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3396 (386bsd is not well tested yet)
3397 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3399 * New file formats supported
3401 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3402 supports reading of `a.out.adobe' object files, which are an a.out
3403 format extended with minimal information about multiple sections.
3407 `show copying' is the same as the old `info copying'.
3408 `show warranty' is the same as `info warrantee'.
3409 These were renamed for consistency. The old commands continue to work.
3411 `info handle' is a new alias for `info signals'.
3413 You can now define pre-command hooks, which attach arbitrary command
3414 scripts to any command. The commands in the hook will be executed
3415 prior to the user's command. You can also create a hook which will be
3416 executed whenever the program stops. See gdb.texinfo.
3420 We now deal with Cfront style name mangling, and can even extract type
3421 info from mangled symbols. GDB can automatically figure out which
3422 symbol mangling style your C++ compiler uses.
3424 Calling of methods and virtual functions has been improved as well.
3428 The crash that occured when debugging Sun Ansi-C compiled binaries is
3429 fixed. This was due to mishandling of the extra N_SO stabs output
3432 We also finally got Ultrix 4.2 running in house, and fixed core file
3433 support, with help from a dozen people on the net.
3435 John M. Farrell discovered that the reason that single-stepping was so
3436 slow on all of the Mips based platforms (primarily SGI and DEC) was
3437 that we were trying to demangle and lookup a symbol used for internal
3438 purposes on every instruction that was being stepped through. Changing
3439 the name of that symbol so that it couldn't be mistaken for a C++
3440 mangled symbol sped things up a great deal.
3442 Rich Pixley sped up symbol lookups in general by getting much smarter
3443 about when C++ symbol mangling is necessary. This should make symbol
3444 completion (TAB on the command line) much faster. It's not as fast as
3445 we'd like, but it's significantly faster than gdb-4.6.
3449 A new user controllable variable 'call_scratch_address' can
3450 specify the location of a scratch area to be used when GDB
3451 calls a function in the target. This is necessary because the
3452 usual method of putting the scratch area on the stack does not work
3453 in systems that have separate instruction and data spaces.
3455 We integrated changes to support the 29k UDI (Universal Debugger
3456 Interface), but discovered at the last minute that we didn't have all
3457 of the appropriate copyright paperwork. We are working with AMD to
3458 resolve this, and hope to have it available soon.
3462 We have sped up the remote serial line protocol, especially for targets
3463 with lots of registers. It now supports a new `expedited status' ('T')
3464 message which can be used in place of the existing 'S' status message.
3465 This allows the remote stub to send only the registers that GDB
3466 needs to make a quick decision about single-stepping or conditional
3467 breakpoints, eliminating the need to fetch the entire register set for
3468 each instruction being stepped through.
3470 The GDB remote serial protocol now implements a write-through cache for
3471 registers, only re-reading the registers if the target has run.
3473 There is also a new remote serial stub for SPARC processors. You can
3474 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3475 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3476 processor with a serial port.
3480 Configure.in files have become much easier to read and modify. A new
3481 `table driven' format makes it more obvious what configurations are
3482 supported, and what files each one uses.
3486 There is a new opcodes library which will eventually contain all of the
3487 disassembly routines and opcode tables. At present, it only contains
3488 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3489 disassembler (binutils/objdump) to share these routines.
3491 The libiberty library is now copylefted under the GNU Library General
3492 Public License. This allows more liberal use, and was done so libg++
3493 can use it. This makes no difference to GDB, since the Library License
3494 grants all the rights from the General Public License.
3498 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3499 reference to the stabs symbol info used by the debugger. It is (as far
3500 as we know) the only published document on this fascinating topic. We
3501 encourage you to read it, compare it to the stabs information on your
3502 system, and send improvements on the document in general (to
3503 bug-gdb@prep.ai.mit.edu).
3505 And, of course, many bugs have been fixed.
3508 *** Changes in GDB-4.6:
3510 * Better support for C++ function names
3512 GDB now accepts as input the "demangled form" of C++ overloaded function
3513 names and member function names, and can do command completion on such names
3514 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3515 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3516 Make use of command completion, it is your friend.
3518 GDB also now accepts a variety of C++ mangled symbol formats. They are
3519 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3520 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3521 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3522 for the list of formats.
3524 * G++ symbol mangling problem
3526 Recent versions of gcc have a bug in how they emit debugging information for
3527 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3528 directory) can be applied to gcc to fix the problem. Alternatively, if you
3529 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3530 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3531 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3534 * New 'maintenance' command
3536 All of the commands related to hacking GDB internals have been moved out of
3537 the main command set, and now live behind the 'maintenance' command. This
3538 can also be abbreviated as 'mt'. The following changes were made:
3540 dump-me -> maintenance dump-me
3541 info all-breakpoints -> maintenance info breakpoints
3542 printmsyms -> maintenance print msyms
3543 printobjfiles -> maintenance print objfiles
3544 printpsyms -> maintenance print psymbols
3545 printsyms -> maintenance print symbols
3547 The following commands are new:
3549 maintenance demangle Call internal GDB demangler routine to
3550 demangle a C++ link name and prints the result.
3551 maintenance print type Print a type chain for a given symbol
3553 * Change to .gdbinit file processing
3555 We now read the $HOME/.gdbinit file before processing the argv arguments
3556 (e.g. reading symbol files or core files). This allows global parameters to
3557 be set, which will apply during the symbol reading. The ./.gdbinit is still
3558 read after argv processing.
3560 * New hosts supported
3562 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3564 GNU/Linux support i386-unknown-linux or linux
3566 We are also including code to support the HP/PA running BSD and HPUX. This
3567 is almost guaranteed not to work, as we didn't have time to test or build it
3568 for this release. We are including it so that the more adventurous (or
3569 masochistic) of you can play with it. We also had major problems with the
3570 fact that the compiler that we got from HP doesn't support the -g option.
3573 * New targets supported
3575 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3577 * More smarts about finding #include files
3579 GDB now remembers the compilation directory for all include files, and for
3580 all files from which C is generated (like yacc and lex sources). This
3581 greatly improves GDB's ability to find yacc/lex sources, and include files,
3582 especially if you are debugging your program from a directory different from
3583 the one that contains your sources.
3585 We also fixed a bug which caused difficulty with listing and setting
3586 breakpoints in include files which contain C code. (In the past, you had to
3587 try twice in order to list an include file that you hadn't looked at before.)
3589 * Interesting infernals change
3591 GDB now deals with arbitrary numbers of sections, where the symbols for each
3592 section must be relocated relative to that section's landing place in the
3593 target's address space. This work was needed to support ELF with embedded
3594 stabs used by Solaris-2.0.
3596 * Bug fixes (of course!)
3598 There have been loads of fixes for the following things:
3599 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3600 i960, stabs, DOS(GO32), procfs, etc...
3602 See the ChangeLog for details.
3604 *** Changes in GDB-4.5:
3606 * New machines supported (host and target)
3608 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3610 SGI Irix-4.x mips-sgi-irix4 or iris4
3612 * New malloc package
3614 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3615 Mmalloc is capable of handling mutiple heaps of memory. It is also
3616 capable of saving a heap to a file, and then mapping it back in later.
3617 This can be used to greatly speedup the startup of GDB by using a
3618 pre-parsed symbol table which lives in a mmalloc managed heap. For
3619 more details, please read mmalloc/mmalloc.texi.
3623 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3624 'help info proc' for details.
3626 * MIPS ecoff symbol table format
3628 The code that reads MIPS symbol table format is now supported on all hosts.
3629 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3632 * File name changes for MS-DOS
3634 Many files in the config directories have been renamed to make it easier to
3635 support GDB on MS-DOSe systems (which have very restrictive file name
3636 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3637 environment) is close to working but has some remaining problems. Note
3638 that debugging of DOS programs is not supported, due to limitations
3639 in the ``operating system'', but it can be used to host cross-debugging.
3641 * Cross byte order fixes
3643 Many fixes have been made to support cross debugging of Sparc and MIPS
3644 targets from hosts whose byte order differs.
3646 * New -mapped and -readnow options
3648 If memory-mapped files are available on your system through the 'mmap'
3649 system call, you can use the -mapped option on the `file' or
3650 `symbol-file' commands to cause GDB to write the symbols from your
3651 program into a reusable file. If the program you are debugging is
3652 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3653 Future GDB debugging sessions will notice the presence of this file,
3654 and will quickly map in symbol information from it, rather than reading
3655 the symbol table from the executable program. Using the '-mapped'
3656 option in a GDB `file' or `symbol-file' command has the same effect as
3657 starting GDB with the '-mapped' command-line option.
3659 You can cause GDB to read the entire symbol table immediately by using
3660 the '-readnow' option with any of the commands that load symbol table
3661 information (or on the GDB command line). This makes the command
3662 slower, but makes future operations faster.
3664 The -mapped and -readnow options are typically combined in order to
3665 build a `fred.syms' file that contains complete symbol information.
3666 A simple GDB invocation to do nothing but build a `.syms' file for future
3669 gdb -batch -nx -mapped -readnow programname
3671 The `.syms' file is specific to the host machine on which GDB is run.
3672 It holds an exact image of GDB's internal symbol table. It cannot be
3673 shared across multiple host platforms.
3675 * longjmp() handling
3677 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3678 siglongjmp() without losing control. This feature has not yet been ported to
3679 all systems. It currently works on many 386 platforms, all MIPS-based
3680 platforms (SGI, DECstation, etc), and Sun3/4.
3684 Preliminary work has been put in to support the new Solaris OS from Sun. At
3685 this time, it can control and debug processes, but it is not capable of
3690 As always, many many bug fixes. The major areas were with g++, and mipsread.
3691 People using the MIPS-based platforms should experience fewer mysterious
3692 crashes and trashed symbol tables.
3694 *** Changes in GDB-4.4:
3696 * New machines supported (host and target)
3698 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3700 BSD Reno on Vax vax-dec-bsd
3701 Ultrix on Vax vax-dec-ultrix
3703 * New machines supported (target)
3705 AMD 29000 embedded, using EBMON a29k-none-none
3709 GDB continues to improve its handling of C++. `References' work better.
3710 The demangler has also been improved, and now deals with symbols mangled as
3711 per the Annotated C++ Reference Guide.
3713 GDB also now handles `stabs' symbol information embedded in MIPS
3714 `ecoff' symbol tables. Since the ecoff format was not easily
3715 extensible to handle new languages such as C++, this appeared to be a
3716 good way to put C++ debugging info into MIPS binaries. This option
3717 will be supported in the GNU C compiler, version 2, when it is
3720 * New features for SVR4
3722 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3723 shared libraries. Debugging dynamically linked programs should present
3724 only minor differences from debugging statically linked programs.
3726 The `info proc' command will print out information about any process
3727 on an SVR4 system (including the one you are debugging). At the moment,
3728 it prints the address mappings of the process.
3730 If you bring up GDB on another SVR4 system, please send mail to
3731 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3733 * Better dynamic linking support in SunOS
3735 Reading symbols from shared libraries which contain debugging symbols
3736 now works properly. However, there remain issues such as automatic
3737 skipping of `transfer vector' code during function calls, which
3738 make it harder to debug code in a shared library, than to debug the
3739 same code linked statically.
3743 GDB is now using the latest `getopt' routines from the FSF. This
3744 version accepts the -- prefix for options with long names. GDB will
3745 continue to accept the old forms (-option and +option) as well.
3746 Various single letter abbreviations for options have been explicity
3747 added to the option table so that they won't get overshadowed in the
3748 future by other options that begin with the same letter.
3752 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3753 Many assorted bugs have been handled. Many more remain to be handled.
3754 See the various ChangeLog files (primarily in gdb and bfd) for details.
3757 *** Changes in GDB-4.3:
3759 * New machines supported (host and target)
3761 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3762 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3763 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3765 * Almost SCO Unix support
3767 We had hoped to support:
3768 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3769 (except for core file support), but we discovered very late in the release
3770 that it has problems with process groups that render gdb unusable. Sorry
3771 about that. I encourage people to fix it and post the fixes.
3773 * Preliminary ELF and DWARF support
3775 GDB can read ELF object files on System V Release 4, and can handle
3776 debugging records for C, in DWARF format, in ELF files. This support
3777 is preliminary. If you bring up GDB on another SVR4 system, please
3778 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3783 GDB now uses the latest `readline' library. One user-visible change
3784 is that two tabs will list possible command completions, which previously
3785 required typing M-? (meta-question mark, or ESC ?).
3789 The `stepi' bug that many of you noticed has been squashed.
3790 Many bugs in C++ have been handled. Many more remain to be handled.
3791 See the various ChangeLog files (primarily in gdb and bfd) for details.
3793 * State of the MIPS world (in case you wondered):
3795 GDB can understand the symbol tables emitted by the compilers
3796 supplied by most vendors of MIPS-based machines, including DEC. These
3797 symbol tables are in a format that essentially nobody else uses.
3799 Some versions of gcc come with an assembler post-processor called
3800 mips-tfile. This program is required if you want to do source-level
3801 debugging of gcc-compiled programs. I believe FSF does not ship
3802 mips-tfile with gcc version 1, but it will eventually come with gcc
3805 Debugging of g++ output remains a problem. g++ version 1.xx does not
3806 really support it at all. (If you're lucky, you should be able to get
3807 line numbers and stack traces to work, but no parameters or local
3808 variables.) With some work it should be possible to improve the
3811 When gcc version 2 is released, you will have somewhat better luck.
3812 However, even then you will get confusing results for inheritance and
3815 We will eventually provide full debugging of g++ output on
3816 DECstations. This will probably involve some kind of stabs-in-ecoff
3817 encapulation, but the details have not been worked out yet.
3820 *** Changes in GDB-4.2:
3822 * Improved configuration
3824 Only one copy of `configure' exists now, and it is not self-modifying.
3825 Porting BFD is simpler.
3829 The `step' and `next' commands now only stop at the first instruction
3830 of a source line. This prevents the multiple stops that used to occur
3831 in switch statements, for-loops, etc. `Step' continues to stop if a
3832 function that has debugging information is called within the line.
3836 Lots of small bugs fixed. More remain.
3838 * New host supported (not target)
3840 Intel 386 PC clone running Mach i386-none-mach
3843 *** Changes in GDB-4.1:
3845 * Multiple source language support
3847 GDB now has internal scaffolding to handle several source languages.
3848 It determines the type of each source file from its filename extension,
3849 and will switch expression parsing and number formatting to match the
3850 language of the function in the currently selected stack frame.
3851 You can also specifically set the language to be used, with
3852 `set language c' or `set language modula-2'.
3856 GDB now has preliminary support for the GNU Modula-2 compiler,
3857 currently under development at the State University of New York at
3858 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3859 continue through the fall of 1991 and into 1992.
3861 Other Modula-2 compilers are currently not supported, and attempting to
3862 debug programs compiled with them will likely result in an error as the
3863 symbol table is read. Feel free to work on it, though!
3865 There are hooks in GDB for strict type checking and range checking,
3866 in the `Modula-2 philosophy', but they do not currently work.
3870 GDB can now write to executable and core files (e.g. patch
3871 a variable's value). You must turn this switch on, specify
3872 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3873 by assigning a new value to a variable. Modifications take
3876 * Automatic SunOS shared library reading
3878 When you run your program, GDB automatically determines where its
3879 shared libraries (if any) have been loaded, and reads their symbols.
3880 The `share' command is no longer needed. This also works when
3881 examining core files.
3885 You can specify the number of lines that the `list' command shows.
3888 * New machines supported (host and target)
3890 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3891 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3892 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3894 * New hosts supported (not targets)
3896 IBM RT/PC: romp-ibm-aix or rtpc
3898 * New targets supported (not hosts)
3900 AMD 29000 embedded with COFF a29k-none-coff
3901 AMD 29000 embedded with a.out a29k-none-aout
3902 Ultracomputer remote kernel debug a29k-nyu-kern
3904 * New remote interfaces
3910 *** Changes in GDB-4.0:
3914 Wide output is wrapped at good places to make the output more readable.
3916 Gdb now supports cross-debugging from a host machine of one type to a
3917 target machine of another type. Communication with the target system
3918 is over serial lines. The ``target'' command handles connecting to the
3919 remote system; the ``load'' command will download a program into the
3920 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3921 also supports debugging of realtime processes running under VxWorks,
3922 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3923 stub on the target system.
3925 New CPUs supported include the AMD 29000 and Intel 960.
3927 GDB now reads object files and symbol tables via a ``binary file''
3928 library, which allows a single copy of GDB to debug programs of multiple
3929 object file types such as a.out and coff.
3931 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3932 refcard.dvi and refcard.ps are available to format it).
3935 * Control-Variable user interface simplified
3937 All variables that control the operation of the debugger can be set
3938 by the ``set'' command, and displayed by the ``show'' command.
3940 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3941 ``Show prompt'' produces the response:
3942 Gdb's prompt is new-gdb=>.
3944 What follows are the NEW set commands. The command ``help set'' will
3945 print a complete list of old and new set commands. ``help set FOO''
3946 will give a longer description of the variable FOO. ``show'' will show
3947 all of the variable descriptions and their current settings.
3949 confirm on/off: Enables warning questions for operations that are
3950 hard to recover from, e.g. rerunning the program while
3951 it is already running. Default is ON.
3953 editing on/off: Enables EMACS style command line editing
3954 of input. Previous lines can be recalled with
3955 control-P, the current line can be edited with control-B,
3956 you can search for commands with control-R, etc.
3959 history filename NAME: NAME is where the gdb command history
3960 will be stored. The default is .gdb_history,
3961 or the value of the environment variable
3964 history size N: The size, in commands, of the command history. The
3965 default is 256, or the value of the environment variable
3968 history save on/off: If this value is set to ON, the history file will
3969 be saved after exiting gdb. If set to OFF, the
3970 file will not be saved. The default is OFF.
3972 history expansion on/off: If this value is set to ON, then csh-like
3973 history expansion will be performed on
3974 command line input. The default is OFF.
3976 radix N: Sets the default radix for input and output. It can be set
3977 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3978 in the current radix, so "set radix 10" is always a no-op.
3980 height N: This integer value is the number of lines on a page. Default
3981 is 24, the current `stty rows'' setting, or the ``li#''
3982 setting from the termcap entry matching the environment
3985 width N: This integer value is the number of characters on a line.
3986 Default is 80, the current `stty cols'' setting, or the ``co#''
3987 setting from the termcap entry matching the environment
3990 Note: ``set screensize'' is obsolete. Use ``set height'' and
3991 ``set width'' instead.
3993 print address on/off: Print memory addresses in various command displays,
3994 such as stack traces and structure values. Gdb looks
3995 more ``symbolic'' if you turn this off; it looks more
3996 ``machine level'' with it on. Default is ON.
3998 print array on/off: Prettyprint arrays. New convenient format! Default
4001 print demangle on/off: Print C++ symbols in "source" form if on,
4004 print asm-demangle on/off: Same, for assembler level printouts
4007 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4010 * Support for Epoch Environment.
4012 The epoch environment is a version of Emacs v18 with windowing. One
4013 new command, ``inspect'', is identical to ``print'', except that if you
4014 are running in the epoch environment, the value is printed in its own
4018 * Support for Shared Libraries
4020 GDB can now debug programs and core files that use SunOS shared libraries.
4021 Symbols from a shared library cannot be referenced
4022 before the shared library has been linked with the program (this
4023 happens after you type ``run'' and before the function main() is entered).
4024 At any time after this linking (including when examining core files
4025 from dynamically linked programs), gdb reads the symbols from each
4026 shared library when you type the ``sharedlibrary'' command.
4027 It can be abbreviated ``share''.
4029 sharedlibrary REGEXP: Load shared object library symbols for files
4030 matching a unix regular expression. No argument
4031 indicates to load symbols for all shared libraries.
4033 info sharedlibrary: Status of loaded shared libraries.
4038 A watchpoint stops execution of a program whenever the value of an
4039 expression changes. Checking for this slows down execution
4040 tremendously whenever you are in the scope of the expression, but is
4041 quite useful for catching tough ``bit-spreader'' or pointer misuse
4042 problems. Some machines such as the 386 have hardware for doing this
4043 more quickly, and future versions of gdb will use this hardware.
4045 watch EXP: Set a watchpoint (breakpoint) for an expression.
4047 info watchpoints: Information about your watchpoints.
4049 delete N: Deletes watchpoint number N (same as breakpoints).
4050 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4051 enable N: Re-enables watchpoint number N (same as breakpoints).
4054 * C++ multiple inheritance
4056 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4059 * C++ exception handling
4061 Gdb now supports limited C++ exception handling. Besides the existing
4062 ability to breakpoint on an exception handler, gdb can breakpoint on
4063 the raising of an exception (before the stack is peeled back to the
4066 catch FOO: If there is a FOO exception handler in the dynamic scope,
4067 set a breakpoint to catch exceptions which may be raised there.
4068 Multiple exceptions (``catch foo bar baz'') may be caught.
4070 info catch: Lists all exceptions which may be caught in the
4071 current stack frame.
4074 * Minor command changes
4076 The command ``call func (arg, arg, ...)'' now acts like the print
4077 command, except it does not print or save a value if the function's result
4078 is void. This is similar to dbx usage.
4080 The ``up'' and ``down'' commands now always print the frame they end up
4081 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4082 frames without printing.
4084 * New directory command
4086 'dir' now adds directories to the FRONT of the source search path.
4087 The path starts off empty. Source files that contain debug information
4088 about the directory in which they were compiled can be found even
4089 with an empty path; Sun CC and GCC include this information. If GDB can't
4090 find your source file in the current directory, type "dir .".
4092 * Configuring GDB for compilation
4094 For normal use, type ``./configure host''. See README or gdb.texinfo
4097 GDB now handles cross debugging. If you are remotely debugging between
4098 two different machines, type ``./configure host -target=targ''.
4099 Host is the machine where GDB will run; targ is the machine
4100 where the program that you are debugging will run.