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.
23 In response to several of the tracepoint packets, the target may now
24 also respond with a number of intermediate `qRelocInsn' request
25 packets before the final result packet, to have GDB handle
26 relocating an instruction to execute at a different address. This
27 is particularly useful for stubs that support fast tracepoints. GDB
28 reports support for this feature in the qSupported packet.
30 * The source command now accepts a -s option to force searching for the
31 script in the source search path even if the script name specifies
34 * New features in the GDB remote stub, GDBserver
36 - GDBserver now support tracepoints (including fast tracepoints).
37 The feature is currently supported by the i386-linux and
38 amd64-linux builds. See the "Tracepoints support in gdbserver"
39 section in the manual for more information. GDBserver JIT
40 compiles the tracepoint's conditional agent expression bytecode
41 into native code whenever possible for low overhead dynamic
42 tracepoints conditionals. For such tracepoints, an expression
43 that examines program state is evaluated when the tracepoint is
44 reached, in order to determine whether to capture trace data. If
45 the condition is simple and false, processing the tracepoint
46 finishes very quickly and no data is gathered.
48 - GDBserver now supports x86_64 Windows 64-bit debugging.
50 * GDB now sends xmlRegisters= in qSupported packet to indicate that
51 it understands register description.
53 * The --batch flag now disables pagination and queries.
55 * X86 general purpose registers
57 GDB now supports reading/writing byte, word and double-word x86
58 general purpose registers directly. This means you can use, say,
59 $ah or $ax to refer, respectively, to the byte register AH and
60 16-bit word register AX that are actually portions of the 32-bit
61 register EAX or 64-bit register RAX.
63 * The `commands' command now accepts a range of breakpoints to modify.
64 A plain `commands' following a command that creates multiple
65 breakpoints affects all the breakpoints set by that command. This
66 applies to breakpoints set by `rbreak', and also applies when a
67 single `break' command creates multiple breakpoints (e.g.,
68 breakpoints on overloaded c++ functions).
70 * The `rbreak' command now accepts a filename specification as part of
71 its argument, limiting the functions selected by the regex to those
72 in the specified file.
74 * Support for remote debugging Windows and SymbianOS shared libraries
75 from Unix hosts has been improved. Non Windows GDB builds now can
76 understand target reported file names that follow MS-DOS based file
77 system semantics, such as file names that include drive letters and
78 use the backslash character as directory separator. This makes it
79 possible to transparently use the "set sysroot" and "set
80 solib-search-path" on Unix hosts to point as host copies of the
81 target's shared libraries. See the new command "set
82 target-file-system-kind" described below, and the "Commands to
83 specify files" section in the user manual for more information.
87 eval template, expressions...
88 Convert the values of one or more expressions under the control
89 of the string template to a command line, and call it.
91 set target-file-system-kind unix|dos-based|auto
92 show target-file-system-kind
93 Set or show the assumed file system kind for target reported file
96 save breakpoints <filename>
97 Save all current breakpoint definitions to a file suitable for use
98 in a later debugging session. To read the saved breakpoint
99 definitions, use the `source' command.
101 `save tracepoints' is a new alias for `save-tracepoints'. The latter
106 ** The GDB Python API now has access to breakpoints, symbols, symbol
107 tables, program spaces, and frame's code blocks. Additionally, GDB
108 Parameters can now be created from the API, and manipulated via
111 ** New functions gdb.target_charset, gdb.target_wide_charset,
112 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
114 ** New exception gdb.GdbError.
116 ** Pretty-printers are now also looked up in the current program space.
118 ** Pretty-printers can now be individually enabled and disabled.
120 ** GDB now looks for names of Python scripts to auto-load in a
121 special section named `.debug_gdb_scripts', in addition to looking
122 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
124 * Tracepoint actions were unified with breakpoint commands. In particular,
125 there are no longer differences in "info break" output for breakpoints and
126 tracepoints and the "commands" command can be used for both tracepoints and
131 ARM Symbian arm*-*-symbianelf*
133 * D language support.
134 GDB now supports debugging programs written in the D programming
137 *** Changes in GDB 7.1
143 GDB now supports importing of namespaces in C++. This enables the
144 user to inspect variables from imported namespaces. Support for
145 namepace aliasing has also been added. So, if a namespace is
146 aliased in the current scope (e.g. namepace C=A; ) the user can
147 print variables using the alias (e.g. (gdb) print C::x).
151 All known bugs relating to the printing of virtual base class were
152 fixed. It is now possible to call overloaded static methods using a
157 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
158 and reinterpret_cast<> are now handled by the C++ expression parser.
162 Xilinx MicroBlaze microblaze-*-*
167 Xilinx MicroBlaze microblaze
170 * Multi-program debugging.
172 GDB now has support for multi-program (a.k.a. multi-executable or
173 multi-exec) debugging. This allows for debugging multiple inferiors
174 simultaneously each running a different program under the same GDB
175 session. See "Debugging Multiple Inferiors and Programs" in the
176 manual for more information. This implied some user visible changes
177 in the multi-inferior support. For example, "info inferiors" now
178 lists inferiors that are not running yet or that have exited
179 already. See also "New commands" and "New options" below.
181 * New tracing features
183 GDB's tracepoint facility now includes several new features:
185 ** Trace state variables
187 GDB tracepoints now include support for trace state variables, which
188 are variables managed by the target agent during a tracing
189 experiment. They are useful for tracepoints that trigger each
190 other, so for instance one tracepoint can count hits in a variable,
191 and then a second tracepoint has a condition that is true when the
192 count reaches a particular value. Trace state variables share the
193 $-syntax of GDB convenience variables, and can appear in both
194 tracepoint actions and condition expressions. Use the "tvariable"
195 command to create, and "info tvariables" to view; see "Trace State
196 Variables" in the manual for more detail.
200 GDB now includes an option for defining fast tracepoints, which
201 targets may implement more efficiently, such as by installing a jump
202 into the target agent rather than a trap instruction. The resulting
203 speedup can be by two orders of magnitude or more, although the
204 tradeoff is that some program locations on some target architectures
205 might not allow fast tracepoint installation, for instance if the
206 instruction to be replaced is shorter than the jump. To request a
207 fast tracepoint, use the "ftrace" command, with syntax identical to
208 the regular trace command.
210 ** Disconnected tracing
212 It is now possible to detach GDB from the target while it is running
213 a trace experiment, then reconnect later to see how the experiment
214 is going. In addition, a new variable disconnected-tracing lets you
215 tell the target agent whether to continue running a trace if the
216 connection is lost unexpectedly.
220 GDB now has the ability to save the trace buffer into a file, and
221 then use that file as a target, similarly to you can do with
222 corefiles. You can select trace frames, print data that was
223 collected in them, and use tstatus to display the state of the
224 tracing run at the moment that it was saved. To create a trace
225 file, use "tsave <filename>", and to use it, do "target tfile
228 ** Circular trace buffer
230 You can ask the target agent to handle the trace buffer as a
231 circular buffer, discarding the oldest trace frames to make room for
232 newer ones, by setting circular-trace-buffer to on. This feature may
233 not be available for all target agents.
238 The disassemble command, when invoked with two arguments, now requires
239 the arguments to be comma-separated.
242 The info variables command now displays variable definitions. Files
243 which only declare a variable are not shown.
246 The source command is now capable of sourcing Python scripts.
247 This feature is dependent on the debugger being build with Python
250 Related to this enhancement is also the introduction of a new command
251 "set script-extension" (see below).
253 * New commands (for set/show, see "New options" below)
255 record save [<FILENAME>]
256 Save a file (in core file format) containing the process record
257 execution log for replay debugging at a later time.
259 record restore <FILENAME>
260 Restore the process record execution log that was saved at an
261 earlier time, for replay debugging.
263 add-inferior [-copies <N>] [-exec <FILENAME>]
266 clone-inferior [-copies <N>] [ID]
267 Make a new inferior ready to execute the same program another
273 maint info program-spaces
274 List the program spaces loaded into GDB.
276 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
277 show remote interrupt-sequence
278 Allow the user to select one of ^C, a BREAK signal or BREAK-g
279 as the sequence to the remote target in order to interrupt the execution.
280 Ctrl-C is a default. Some system prefers BREAK which is high level of
281 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
282 Magic SysRq g. It is BREAK signal and character 'g'.
284 set remote interrupt-on-connect [on | off]
285 show remote interrupt-on-connect
286 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
287 remote target when gdb connects to it. This is needed when you debug
290 set remotebreak [on | off]
292 Deprecated. Use "set/show remote interrupt-sequence" instead.
294 tvariable $NAME [ = EXP ]
295 Create or modify a trace state variable.
298 List trace state variables and their values.
300 delete tvariable $NAME ...
301 Delete one or more trace state variables.
304 Evaluate the given expressions without collecting anything into the
305 trace buffer. (Valid in tracepoint actions only.)
307 ftrace FN / FILE:LINE / *ADDR
308 Define a fast tracepoint at the given function, line, or address.
310 * New expression syntax
312 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
313 GDB now parses 0b101010 identically with 42.
317 set follow-exec-mode new|same
318 show follow-exec-mode
319 Control whether GDB reuses the same inferior across an exec call or
320 creates a new one. This is useful to be able to restart the old
321 executable after the inferior having done an exec call.
323 set default-collect EXPR, ...
325 Define a list of expressions to be collected at each tracepoint.
326 This is a useful way to ensure essential items are not overlooked,
327 such as registers or a critical global variable.
329 set disconnected-tracing
330 show disconnected-tracing
331 If set to 1, the target is instructed to continue tracing if it
332 loses its connection to GDB. If 0, the target is to stop tracing
335 set circular-trace-buffer
336 show circular-trace-buffer
337 If set to on, the target is instructed to use a circular trace buffer
338 and discard the oldest trace frames instead of stopping the trace due
339 to a full trace buffer. If set to off, the trace stops when the buffer
340 fills up. Some targets may not support this.
342 set script-extension off|soft|strict
343 show script-extension
344 If set to "off", the debugger does not perform any script language
345 recognition, and all sourced files are assumed to be GDB scripts.
346 If set to "soft" (the default), files are sourced according to
347 filename extension, falling back to GDB scripts if the first
349 If set to "strict", files are sourced according to filename extension.
351 set ada trust-PAD-over-XVS on|off
352 show ada trust-PAD-over-XVS
353 If off, activate a workaround against a bug in the debugging information
354 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
355 the GCC sources for more information about the GNAT encoding and
356 PAD types in particular). It is always safe to set this option to
357 off, but this introduces a slight performance penalty. The default
360 * Python API Improvements
362 ** GDB provides the new class gdb.LazyString. This is useful in
363 some pretty-printing cases. The new method gdb.Value.lazy_string
364 provides a simple way to create objects of this type.
366 ** The fields returned by gdb.Type.fields now have an
367 `is_base_class' attribute.
369 ** The new method gdb.Type.range returns the range of an array type.
371 ** The new method gdb.parse_and_eval can be used to parse and
372 evaluate an expression.
377 Define a trace state variable.
380 Get the current value of a trace state variable.
383 Set desired tracing behavior upon disconnection.
386 Set the trace buffer to be linear or circular.
389 Get data about the tracepoints currently in use.
393 Process record now works correctly with hardware watchpoints.
395 Multiple bug fixes have been made to the mips-irix port, making it
396 much more reliable. In particular:
397 - Debugging threaded applications is now possible again. Previously,
398 GDB would hang while starting the program, or while waiting for
399 the program to stop at a breakpoint.
400 - Attaching to a running process no longer hangs.
401 - An error occurring while loading a core file has been fixed.
402 - Changing the value of the PC register now works again. This fixes
403 problems observed when using the "jump" command, or when calling
404 a function from GDB, or even when assigning a new value to $pc.
405 - With the "finish" and "return" commands, the return value for functions
406 returning a small array is now correctly printed.
407 - It is now possible to break on shared library code which gets executed
408 during a shared library init phase (code executed while executing
409 their .init section). Previously, the breakpoint would have no effect.
410 - GDB is now able to backtrace through the signal handler for
411 non-threaded programs.
413 PIE (Position Independent Executable) programs debugging is now supported.
414 This includes debugging execution of PIC (Position Independent Code) shared
415 libraries although for that, it should be possible to run such libraries as an
418 *** Changes in GDB 7.0
420 * GDB now has an interface for JIT compilation. Applications that
421 dynamically generate code can create symbol files in memory and register
422 them with GDB. For users, the feature should work transparently, and
423 for JIT developers, the interface is documented in the GDB manual in the
424 "JIT Compilation Interface" chapter.
426 * Tracepoints may now be conditional. The syntax is as for
427 breakpoints; either an "if" clause appended to the "trace" command,
428 or the "condition" command is available. GDB sends the condition to
429 the target for evaluation using the same bytecode format as is used
430 for tracepoint actions.
432 * "disassemble" command with a /r modifier, print the raw instructions
433 in hex as well as in symbolic form.
435 * Process record and replay
437 In a architecture environment that supports ``process record and
438 replay'', ``process record and replay'' target can record a log of
439 the process execution, and replay it with both forward and reverse
442 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
443 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
444 set execution-direction {forward|reverse}, for targets that support
447 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
448 feature is available with a native GDB running on kernel version
451 * GDB now has support for multi-byte and wide character sets on the
452 target. Strings whose character type is wchar_t, char16_t, or
453 char32_t are now correctly printed. GDB supports wide- and unicode-
454 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
455 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
456 `printf'. This feature requires iconv to work properly; if your
457 system does not have a working iconv, GDB can use GNU libiconv. See
458 the installation instructions for more information.
460 * GDB now supports automatic retrieval of shared library files from
461 remote targets. To use this feature, specify a system root that begins
462 with the `remote:' prefix, either via the `set sysroot' command or via
463 the `--with-sysroot' configure-time option.
465 * "info sharedlibrary" now takes an optional regex of libraries to show,
466 and it now reports if a shared library has no debugging information.
468 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
469 now complete on file names.
471 * When completing in expressions, gdb will attempt to limit
472 completions to allowable structure or union fields, where appropriate.
473 For instance, consider:
475 # struct example { int f1; double f2; };
476 # struct example variable;
479 If the user types TAB at the end of this command line, the available
480 completions will be "f1" and "f2".
482 * Inlined functions are now supported. They show up in backtraces, and
483 the "step", "next", and "finish" commands handle them automatically.
485 * GDB now supports the token-splicing (##) and stringification (#)
486 operators when expanding macros. It also supports variable-arity
489 * GDB now supports inspecting extra signal information, exported by
490 the new $_siginfo convenience variable. The feature is currently
491 implemented on linux ARM, i386 and amd64.
493 * GDB can now display the VFP floating point registers and NEON vector
494 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
495 can provide these registers (requires Linux 2.6.30 or later). Remote
496 and simulator targets may also provide them.
501 Search memory for a sequence of bytes.
504 Turn off `+'/`-' protocol acknowledgments to permit more efficient
505 operation over reliable transport links. Use of this packet is
506 controlled by the `set remote noack-packet' command.
509 Kill the process with the specified process ID. Use this in preference
510 to `k' when multiprocess protocol extensions are supported.
513 Obtains additional operating system information
517 Read or write additional signal information.
519 * Removed remote protocol undocumented extension
521 An undocumented extension to the remote protocol's `S' stop reply
522 packet that permited the stub to pass a process id was removed.
523 Remote servers should use the `T' stop reply packet instead.
525 * The "disassemble" command now supports an optional /m modifier to print mixed
528 * GDB now supports multiple function calling conventions according to the
529 DWARF-2 DW_AT_calling_convention function attribute.
531 * The SH target utilizes the aforementioned change to distinguish between gcc
532 and Renesas calling convention. It also adds the new CLI commands
533 `set/show sh calling-convention'.
535 * GDB can now read compressed debug sections, as produced by GNU gold
536 with the --compress-debug-sections=zlib flag.
538 * 64-bit core files are now supported on AIX.
540 * Thread switching is now supported on Tru64.
542 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
543 which will be allocated using malloc later in program execution.
545 * The qXfer:libraries:read remote procotol packet now allows passing a
546 list of section offsets.
548 * On GNU/Linux, GDB can now attach to stopped processes. Several race
549 conditions handling signals delivered during attach or thread creation
550 have also been fixed.
552 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
553 From the user's standpoint, all unqualified instances of True and False
554 are treated as the standard definitions, regardless of context.
556 * GDB now parses C++ symbol and type names more flexibly. For
559 template<typename T> class C { };
562 GDB will now correctly handle all of:
564 ptype C<char const *>
566 ptype C<const char *>
569 * New features in the GDB remote stub, gdbserver
571 - The "--wrapper" command-line argument tells gdbserver to use a
572 wrapper program to launch programs for debugging.
574 - On PowerPC and S/390 targets, it is now possible to use a single
575 gdbserver executable to debug both 32-bit and 64-bit programs.
576 (This requires gdbserver itself to be built as a 64-bit executable.)
578 - gdbserver uses the new noack protocol mode for TCP connections to
579 reduce communications latency, if also supported and enabled in GDB.
581 - Support for the sparc64-linux-gnu target is now included in
584 - The amd64-linux build of gdbserver now supports debugging both
585 32-bit and 64-bit programs.
587 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
588 now support hardware watchpoints, and will use them automatically
593 GDB now has support for scripting using Python. Whether this is
594 available is determined at configure time.
596 New GDB commands can now be written in Python.
598 * Ada tasking support
600 Ada tasks can now be inspected in GDB. The following commands have
604 Print the list of Ada tasks.
606 Print detailed information about task number N.
608 Print the task number of the current task.
610 Switch the context of debugging to task number N.
612 * Support for user-defined prefixed commands. The "define" command can
613 add new commands to existing prefixes, e.g. "target".
615 * Multi-inferior, multi-process debugging.
617 GDB now has generalized support for multi-inferior debugging. See
618 "Debugging Multiple Inferiors" in the manual for more information.
619 Although availability still depends on target support, the command
620 set is more uniform now. The GNU/Linux specific multi-forks support
621 has been migrated to this new framework. This implied some user
622 visible changes; see "New commands" and also "Removed commands"
625 * Target descriptions can now describe the target OS ABI. See the
626 "Target Description Format" section in the user manual for more
629 * Target descriptions can now describe "compatible" architectures
630 to indicate that the target can execute applications for a different
631 architecture in addition to those for the main target architecture.
632 See the "Target Description Format" section in the user manual for
635 * Multi-architecture debugging.
637 GDB now includes general supports for debugging applications on
638 hybrid systems that use more than one single processor architecture
639 at the same time. Each such hybrid architecture still requires
640 specific support to be added. The only hybrid architecture supported
641 in this version of GDB is the Cell Broadband Engine.
643 * GDB now supports integrated debugging of Cell/B.E. applications that
644 use both the PPU and SPU architectures. To enable support for hybrid
645 Cell/B.E. debugging, you need to configure GDB to support both the
646 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
647 --enable-targets configure option.
649 * Non-stop mode debugging.
651 For some targets, GDB now supports an optional mode of operation in
652 which you can examine stopped threads while other threads continue
653 to execute freely. This is referred to as non-stop mode, with the
654 old mode referred to as all-stop mode. See the "Non-Stop Mode"
655 section in the user manual for more information.
657 To be able to support remote non-stop debugging, a remote stub needs
658 to implement the non-stop mode remote protocol extensions, as
659 described in the "Remote Non-Stop" section of the user manual. The
660 GDB remote stub, gdbserver, has been adjusted to support these
661 extensions on linux targets.
663 * New commands (for set/show, see "New options" below)
665 catch syscall [NAME(S) | NUMBER(S)]
666 Catch system calls. Arguments, which should be names of system
667 calls or their numbers, mean catch only those syscalls. Without
668 arguments, every syscall will be caught. When the inferior issues
669 any of the specified syscalls, GDB will stop and announce the system
670 call, both when it is called and when its call returns. This
671 feature is currently available with a native GDB running on the
672 Linux Kernel, under the following architectures: x86, x86_64,
673 PowerPC and PowerPC64.
675 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
677 Search memory for a sequence of bytes.
679 maint set python print-stack
680 maint show python print-stack
681 Show a stack trace when an error is encountered in a Python script.
684 Invoke CODE by passing it to the Python interpreter.
689 These allow macros to be defined, undefined, and listed
693 Show operating system information about processes.
696 List the inferiors currently under GDB's control.
699 Switch focus to inferior number NUM.
702 Detach from inferior number NUM.
705 Kill inferior number NUM.
710 show spu stop-on-load
711 Control whether to stop for new SPE threads during Cell/B.E. debugging.
713 set spu auto-flush-cache
714 show spu auto-flush-cache
715 Control whether to automatically flush the software-managed cache
716 during Cell/B.E. debugging.
718 set sh calling-convention
719 show sh calling-convention
720 Control the calling convention used when calling SH target functions.
724 Control display of timestamps with GDB debugging output.
726 set disassemble-next-line
727 show disassemble-next-line
728 Control display of disassembled source lines or instructions when
731 set remote noack-packet
732 show remote noack-packet
733 Set/show the use of remote protocol QStartNoAckMode packet. See above
734 under "New remote packets."
736 set remote query-attached-packet
737 show remote query-attached-packet
738 Control use of remote protocol `qAttached' (query-attached) packet.
740 set remote read-siginfo-object
741 show remote read-siginfo-object
742 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
745 set remote write-siginfo-object
746 show remote write-siginfo-object
747 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
750 set remote reverse-continue
751 show remote reverse-continue
752 Control use of remote protocol 'bc' (reverse-continue) packet.
754 set remote reverse-step
755 show remote reverse-step
756 Control use of remote protocol 'bs' (reverse-step) packet.
758 set displaced-stepping
759 show displaced-stepping
760 Control displaced stepping mode. Displaced stepping is a way to
761 single-step over breakpoints without removing them from the debuggee.
762 Also known as "out-of-line single-stepping".
766 Control display of debugging info for displaced stepping.
768 maint set internal-error
769 maint show internal-error
770 Control what GDB does when an internal error is detected.
772 maint set internal-warning
773 maint show internal-warning
774 Control what GDB does when an internal warning is detected.
779 Use a wrapper program to launch programs for debugging.
781 set multiple-symbols (all|ask|cancel)
782 show multiple-symbols
783 The value of this variable can be changed to adjust the debugger behavior
784 when an expression or a breakpoint location contains an ambiguous symbol
785 name (an overloaded function name, for instance).
787 set breakpoint always-inserted
788 show breakpoint always-inserted
789 Keep breakpoints always inserted in the target, as opposed to inserting
790 them when resuming the target, and removing them when the target stops.
791 This option can improve debugger performance on slow remote targets.
793 set arm fallback-mode (arm|thumb|auto)
794 show arm fallback-mode
795 set arm force-mode (arm|thumb|auto)
797 These commands control how ARM GDB determines whether instructions
798 are ARM or Thumb. The default for both settings is auto, which uses
799 the current CPSR value for instructions without symbols; previous
800 versions of GDB behaved as if "set arm fallback-mode arm".
802 set disable-randomization
803 show disable-randomization
804 Standalone programs run with the virtual address space randomization enabled
805 by default on some platforms. This option keeps the addresses stable across
806 multiple debugging sessions.
810 Control whether other threads are stopped or not when some thread hits
815 Requests that asynchronous execution is enabled in the target, if available.
816 In this case, it's possible to resume target in the background, and interact
817 with GDB while the target is running. "show target-async" displays the
818 current state of asynchronous execution of the target.
820 set target-wide-charset
821 show target-wide-charset
822 The target-wide-charset is the name of the character set that GDB
823 uses when printing characters whose type is wchar_t.
825 set tcp auto-retry (on|off)
827 set tcp connect-timeout
828 show tcp connect-timeout
829 These commands allow GDB to retry failed TCP connections to a remote stub
830 with a specified timeout period; this is useful if the stub is launched
831 in parallel with GDB but may not be ready to accept connections immediately.
833 set libthread-db-search-path
834 show libthread-db-search-path
835 Control list of directories which GDB will search for appropriate
838 set schedule-multiple (on|off)
839 show schedule-multiple
840 Allow GDB to resume all threads of all processes or only threads of
845 Use more aggressive caching for accesses to the stack. This improves
846 performance of remote debugging (particularly backtraces) without
847 affecting correctness.
849 set interactive-mode (on|off|auto)
850 show interactive-mode
851 Control whether GDB runs in interactive mode (on) or not (off).
852 When in interactive mode, GDB waits for the user to answer all
853 queries. Otherwise, GDB does not wait and assumes the default
854 answer. When set to auto (the default), GDB determines which
855 mode to use based on the stdin settings.
860 For program forks, this is replaced by the new more generic `info
861 inferiors' command. To list checkpoints, you can still use the
862 `info checkpoints' command, which was an alias for the `info forks'
866 Replaced by the new `inferior' command. To switch between
867 checkpoints, you can still use the `restart' command, which was an
868 alias for the `fork' command.
871 This is removed, since some targets don't have a notion of
872 processes. To switch between processes, you can still use the
873 `inferior' command using GDB's own inferior number.
876 For program forks, this is replaced by the new more generic `kill
877 inferior' command. To delete a checkpoint, you can still use the
878 `delete checkpoint' command, which was an alias for the `delete
882 For program forks, this is replaced by the new more generic `detach
883 inferior' command. To detach a checkpoint, you can still use the
884 `detach checkpoint' command, which was an alias for the `detach
887 * New native configurations
889 x86/x86_64 Darwin i[34567]86-*-darwin*
891 x86_64 MinGW x86_64-*-mingw*
895 Lattice Mico32 lm32-*
896 x86 DICOS i[34567]86-*-dicos*
897 x86_64 DICOS x86_64-*-dicos*
900 * The GDB remote stub, gdbserver, now supports x86 Windows CE
901 (mingw32ce) debugging.
907 These commands were actually not implemented on any target.
909 *** Changes in GDB 6.8
911 * New native configurations
913 NetBSD/hppa hppa*-*netbsd*
914 Xtensa GNU/Linux xtensa*-*-linux*
918 NetBSD/hppa hppa*-*-netbsd*
919 Xtensa GNU/Lunux xtensa*-*-linux*
921 * Change in command line behavior -- corefiles vs. process ids.
923 When the '-p NUMBER' or '--pid NUMBER' options are used, and
924 attaching to process NUMBER fails, GDB no longer attempts to open a
925 core file named NUMBER. Attaching to a program using the -c option
926 is no longer supported. Instead, use the '-p' or '--pid' options.
928 * GDB can now be built as a native debugger for debugging Windows x86
929 (mingw32) Portable Executable (PE) programs.
931 * Pending breakpoints no longer change their number when their address
934 * GDB now supports breakpoints with multiple locations,
935 including breakpoints on C++ constructors, inside C++ templates,
936 and in inlined functions.
938 * GDB's ability to debug optimized code has been improved. GDB more
939 accurately identifies function bodies and lexical blocks that occupy
940 more than one contiguous range of addresses.
942 * Target descriptions can now describe registers for PowerPC.
944 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
945 registers on PowerPC targets.
947 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
948 targets even when the libthread_db library is not available.
950 * The GDB remote stub, gdbserver, now supports the new file transfer
951 commands (remote put, remote get, and remote delete).
953 * The GDB remote stub, gdbserver, now supports run and attach in
954 extended-remote mode.
956 * hppa*64*-*-hpux11* target broken
957 The debugger is unable to start a program and fails with the following
958 error: "Error trying to get information about dynamic linker".
959 The gdb-6.7 release is also affected.
961 * GDB now supports the --enable-targets= configure option to allow
962 building a single GDB executable that supports multiple remote
963 target architectures.
965 * GDB now supports debugging C and C++ programs which use the
966 Decimal Floating Point extension. In addition, the PowerPC target
967 now has a set of pseudo-registers to inspect decimal float values
968 stored in two consecutive float registers.
970 * The -break-insert MI command can optionally create pending
973 * Improved support for debugging Ada
974 Many improvements to the Ada language support have been made. These
976 - Better support for Ada2005 interface types
977 - Improved handling of arrays and slices in general
978 - Better support for Taft-amendment types
979 - The '{type} ADDRESS' expression is now allowed on the left hand-side
981 - Improved command completion in Ada
984 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
989 set print frame-arguments (all|scalars|none)
990 show print frame-arguments
991 The value of this variable can be changed to control which argument
992 values should be printed by the debugger when displaying a frame.
997 Transfer files to and from a remote target, and delete remote files.
1004 Transfer files to and from a remote target, and delete remote files.
1006 * New remote packets
1013 Open, close, read, write, and delete files on the remote system.
1016 Attach to an existing process on the remote system, in extended-remote
1020 Run a new process on the remote system, in extended-remote mode.
1022 *** Changes in GDB 6.7
1024 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1025 bfd, libiberty and opcodes, as revealed by static analysis donated by
1026 Coverity, Inc. (http://scan.coverity.com).
1028 * When looking up multiply-defined global symbols, GDB will now prefer the
1029 symbol definition in the current shared library if it was built using the
1030 -Bsymbolic linker option.
1032 * When the Text User Interface (TUI) is not configured, GDB will now
1033 recognize the -tui command-line option and print a message that the TUI
1036 * The GDB remote stub, gdbserver, now has lower overhead for high
1037 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1039 * GDB for MIPS targets now autodetects whether a remote target provides
1040 32-bit or 64-bit register values.
1042 * Support for C++ member pointers has been improved.
1044 * GDB now understands XML target descriptions, which specify the
1045 target's overall architecture. GDB can read a description from
1046 a local file or over the remote serial protocol.
1048 * Vectors of single-byte data use a new integer type which is not
1049 automatically displayed as character or string data.
1051 * The /s format now works with the print command. It displays
1052 arrays of single-byte integers and pointers to single-byte integers
1055 * Target descriptions can now describe target-specific registers,
1056 for architectures which have implemented the support (currently
1057 only ARM, M68K, and MIPS).
1059 * GDB and the GDB remote stub, gdbserver, now support the XScale
1062 * The GDB remote stub, gdbserver, has been updated to support
1063 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1064 has been rewritten to use the standard GDB remote protocol.
1066 * GDB can now step into C++ functions which are called through thunks.
1068 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1070 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1071 layout. It also supports a TextSeg= and DataSeg= response when only
1072 segment base addresses (rather than offsets) are available.
1074 * The /i format now outputs any trailing branch delay slot instructions
1075 immediately following the last instruction within the count specified.
1077 * The GDB remote protocol "T" stop reply packet now supports a
1078 "library" response. Combined with the new "qXfer:libraries:read"
1079 packet, this response allows GDB to debug shared libraries on targets
1080 where the operating system manages the list of loaded libraries (e.g.
1081 Windows and SymbianOS).
1083 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1084 (DLLs) on Windows and Windows CE targets.
1086 * GDB now supports a faster verification that a .debug file matches its binary
1087 according to its build-id signature, if the signature is present.
1093 Enable or disable hardware flow control (RTS/CTS) on the serial port
1094 when debugging using remote targets.
1096 set mem inaccessible-by-default
1097 show mem inaccessible-by-default
1098 If the target supplies a memory map, for instance via the remote
1099 protocol's "qXfer:memory-map:read" packet, setting this variable
1100 prevents GDB from accessing memory outside the memory map. This
1101 is useful for targets with memory mapped registers or which react
1102 badly to accesses of unmapped address space.
1104 set breakpoint auto-hw
1105 show breakpoint auto-hw
1106 If the target supplies a memory map, for instance via the remote
1107 protocol's "qXfer:memory-map:read" packet, setting this variable
1108 lets GDB use hardware breakpoints automatically for memory regions
1109 where it can not use software breakpoints. This covers both the
1110 "break" command and internal breakpoints used for other commands
1111 including "next" and "finish".
1114 catch exception unhandled
1115 Stop the program execution when Ada exceptions are raised.
1118 Stop the program execution when an Ada assertion failed.
1122 Set an alternate system root for target files. This is a more
1123 general version of "set solib-absolute-prefix", which is now
1124 an alias to "set sysroot".
1127 Provide extended SPU facility status information. This set of
1128 commands is available only when debugging the Cell/B.E. SPU
1131 * New native configurations
1133 OpenBSD/sh sh*-*openbsd*
1136 unset tdesc filename
1138 Use the specified local file as an XML target description, and do
1139 not query the target for its built-in description.
1143 OpenBSD/sh sh*-*-openbsd*
1144 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1145 Toshiba Media Processor mep-elf
1147 * New remote packets
1150 Ignore the specified signals; pass them directly to the debugged program
1151 without stopping other threads or reporting them to GDB.
1153 qXfer:features:read:
1154 Read an XML target description from the target, which describes its
1159 Read or write contents of an spufs file on the target system. These
1160 packets are available only on the Cell/B.E. SPU architecture.
1162 qXfer:libraries:read:
1163 Report the loaded shared libraries. Combined with new "T" packet
1164 response, this packet allows GDB to debug shared libraries on
1165 targets where the operating system manages the list of loaded
1166 libraries (e.g. Windows and SymbianOS).
1170 Support for these obsolete configurations has been removed.
1178 i[34567]86-*-lynxos*
1179 i[34567]86-*-netware*
1180 i[34567]86-*-sco3.2v5*
1181 i[34567]86-*-sco3.2v4*
1183 i[34567]86-*-sysv4.2*
1186 i[34567]86-*-unixware2*
1187 i[34567]86-*-unixware*
1196 * Other removed features
1203 Various m68k-only ROM monitors.
1210 Various Renesas ROM monitors and debugging interfaces for SH and
1215 Support for a Macraigor serial interface to on-chip debugging.
1216 GDB does not directly support the newer parallel or USB
1221 A debug information format. The predecessor to DWARF 2 and
1222 DWARF 3, which are still supported.
1224 Support for the HP aCC compiler on HP-UX/PA-RISC
1226 SOM-encapsulated symbolic debugging information, automatic
1227 invocation of pxdb, and the aCC custom C++ ABI. This does not
1228 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1229 with aCC can still be debugged on an assembly level.
1231 MIPS ".pdr" sections
1233 A MIPS-specific format used to describe stack frame layout
1234 in debugging information.
1238 GDB could work with an older version of Guile to debug
1239 the interpreter and Scheme programs running in it.
1241 set mips stack-arg-size
1242 set mips saved-gpreg-size
1244 Use "set mips abi" to control parameter passing for MIPS.
1246 *** Changes in GDB 6.6
1251 Cell Broadband Engine SPU spu-elf
1253 * GDB can now be configured as a cross-debugger targeting native Windows
1254 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1255 running on a Windows system over TCP/IP to debug Windows programs.
1257 * The GDB remote stub, gdbserver, has been updated to support Windows and
1258 Cygwin debugging. Both single-threaded and multi-threaded programs are
1261 * The "set trust-readonly-sections" command works again. This command was
1262 broken in GDB 6.3, 6.4, and 6.5.
1264 * The "load" command now supports writing to flash memory, if the remote
1265 stub provides the required support.
1267 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1268 longer requires symbolic debug information (e.g. DWARF-2).
1273 unset substitute-path
1274 show substitute-path
1275 Manage a list of substitution rules that GDB uses to rewrite the name
1276 of the directories where the sources are located. This can be useful
1277 for instance when the sources were moved to a different location
1278 between compilation and debugging.
1282 Print each CLI command as it is executed. Each command is prefixed with
1283 a number of `+' symbols representing the nesting depth.
1284 The source command now has a `-v' option to enable the same feature.
1288 The ARM Demon monitor support (RDP protocol, "target rdp").
1290 Kernel Object Display, an embedded debugging feature which only worked with
1291 an obsolete version of Cisco IOS.
1293 The 'set download-write-size' and 'show download-write-size' commands.
1295 * New remote packets
1298 Tell a stub about GDB client features, and request remote target features.
1299 The first feature implemented is PacketSize, which allows the target to
1300 specify the size of packets it can handle - to minimize the number of
1301 packets required and improve performance when connected to a remote
1305 Fetch an OS auxilliary vector from the remote stub. This packet is a
1306 more efficient replacement for qPart:auxv:read.
1308 qXfer:memory-map:read:
1309 Fetch a memory map from the remote stub, including information about
1310 RAM, ROM, and flash memory devices.
1315 Erase and program a flash memory device.
1317 * Removed remote packets
1320 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1321 used it, and only gdbserver implemented it.
1323 *** Changes in GDB 6.5
1327 Renesas M32C/M16C m32c-elf
1329 Morpho Technologies ms1 ms1-elf
1333 init-if-undefined Initialize a convenience variable, but
1334 only if it doesn't already have a value.
1336 The following commands are presently only implemented for native GNU/Linux:
1338 checkpoint Save a snapshot of the program state.
1340 restart <n> Return the program state to a
1341 previously saved state.
1343 info checkpoints List currently saved checkpoints.
1345 delete-checkpoint <n> Delete a previously saved checkpoint.
1347 set|show detach-on-fork Tell gdb whether to detach from a newly
1348 forked process, or to keep debugging it.
1350 info forks List forks of the user program that
1351 are available to be debugged.
1353 fork <n> Switch to debugging one of several
1354 forks of the user program that are
1355 available to be debugged.
1357 delete-fork <n> Delete a fork from the list of forks
1358 that are available to be debugged (and
1359 kill the forked process).
1361 detach-fork <n> Delete a fork from the list of forks
1362 that are available to be debugged (and
1363 allow the process to continue).
1367 Morpho Technologies ms2 ms1-elf
1369 * Improved Windows host support
1371 GDB now builds as a cross debugger hosted on i686-mingw32, including
1372 native console support, and remote communications using either
1373 network sockets or serial ports.
1375 * Improved Modula-2 language support
1377 GDB can now print most types in the Modula-2 syntax. This includes:
1378 basic types, set types, record types, enumerated types, range types,
1379 pointer types and ARRAY types. Procedure var parameters are correctly
1380 printed and hexadecimal addresses and character constants are also
1381 written in the Modula-2 syntax. Best results can be obtained by using
1382 GNU Modula-2 together with the -gdwarf-2 command line option.
1386 The ARM rdi-share module.
1388 The Netware NLM debug server.
1390 *** Changes in GDB 6.4
1392 * New native configurations
1394 OpenBSD/arm arm*-*-openbsd*
1395 OpenBSD/mips64 mips64-*-openbsd*
1399 Morpho Technologies ms1 ms1-elf
1401 * New command line options
1403 --batch-silent As for --batch, but totally silent.
1404 --return-child-result The debugger will exist with the same value
1405 the child (debugged) program exited with.
1406 --eval-command COMMAND, -ex COMMAND
1407 Execute a single GDB CLI command. This may be
1408 specified multiple times and in conjunction
1409 with the --command (-x) option.
1411 * Deprecated commands removed
1413 The following commands, that were deprecated in 2000, have been
1417 set|show arm disassembly-flavor set|show arm disassembler
1418 othernames set arm disassembler
1419 set|show remotedebug set|show debug remote
1420 set|show archdebug set|show debug arch
1421 set|show eventdebug set|show debug event
1424 * New BSD user-level threads support
1426 It is now possible to debug programs using the user-level threads
1427 library on OpenBSD and FreeBSD. Currently supported (target)
1430 FreeBSD/amd64 x86_64-*-freebsd*
1431 FreeBSD/i386 i386-*-freebsd*
1432 OpenBSD/i386 i386-*-openbsd*
1434 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1435 are not yet supported.
1437 * New support for Matsushita MN10300 w/sim added
1438 (Work in progress). mn10300-elf.
1440 * REMOVED configurations and files
1442 VxWorks and the XDR protocol *-*-vxworks
1443 Motorola MCORE mcore-*-*
1444 National Semiconductor NS32000 ns32k-*-*
1446 * New "set print array-indexes" command
1448 After turning this setting "on", GDB prints the index of each element
1449 when displaying arrays. The default is "off" to preserve the previous
1452 * VAX floating point support
1454 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1456 * User-defined command support
1458 In addition to using $arg0..$arg9 for argument passing, it is now possible
1459 to use $argc to determine now many arguments have been passed. See the
1460 section on user-defined commands in the user manual for more information.
1462 *** Changes in GDB 6.3:
1464 * New command line option
1466 GDB now accepts -l followed by a number to set the timeout for remote
1469 * GDB works with GCC -feliminate-dwarf2-dups
1471 GDB now supports a more compact representation of DWARF-2 debug
1472 information using DW_FORM_ref_addr references. These are produced
1473 by GCC with the option -feliminate-dwarf2-dups and also by some
1474 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1475 to use -feliminate-dwarf2-dups.
1477 * Internationalization
1479 When supported by the host system, GDB will be built with
1480 internationalization (libintl). The task of marking up the sources is
1481 continued, we're looking forward to our first translation.
1485 Initial support for debugging programs compiled with the GNAT
1486 implementation of the Ada programming language has been integrated
1487 into GDB. In this release, support is limited to expression evaluation.
1489 * New native configurations
1491 GNU/Linux/m32r m32r-*-linux-gnu
1495 GDB's remote protocol now includes support for the 'p' packet. This
1496 packet is used to fetch individual registers from a remote inferior.
1498 * END-OF-LIFE registers[] compatibility module
1500 GDB's internal register infrastructure has been completely rewritten.
1501 The new infrastructure making possible the implementation of key new
1502 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1505 GDB 6.3 will be the last release to include the the registers[]
1506 compatibility module that allowed out-of-date configurations to
1507 continue to work. This change directly impacts the following
1517 powerpc bdm protocol
1519 Unless there is activity to revive these configurations, they will be
1520 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1522 * OBSOLETE configurations and files
1524 Configurations that have been declared obsolete in this release have
1525 been commented out. Unless there is activity to revive these
1526 configurations, the next release of GDB will have their sources
1527 permanently REMOVED.
1536 *** Changes in GDB 6.2.1:
1538 * MIPS `break main; run' gave an heuristic-fence-post warning
1540 When attempting to run even a simple program, a warning about
1541 heuristic-fence-post being hit would be reported. This problem has
1544 * MIPS IRIX 'long double' crashed GDB
1546 When examining a long double variable, GDB would get a segmentation
1547 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1548 IRIX long double values).
1552 A bug in the VAX stack code was causing problems with the "next"
1553 command. This problem has been fixed.
1555 *** Changes in GDB 6.2:
1557 * Fix for ``many threads''
1559 On GNU/Linux systems that use the NPTL threads library, a program
1560 rapidly creating and deleting threads would confuse GDB leading to the
1563 ptrace: No such process.
1564 thread_db_get_info: cannot get thread info: generic error
1566 This problem has been fixed.
1568 * "-async" and "-noasync" options removed.
1570 Support for the broken "-noasync" option has been removed (it caused
1573 * New ``start'' command.
1575 This command runs the program until the begining of the main procedure.
1577 * New BSD Kernel Data Access Library (libkvm) interface
1579 Using ``target kvm'' it is now possible to debug kernel core dumps and
1580 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1581 platforms. Currently supported (native-only) configurations are:
1583 FreeBSD/amd64 x86_64-*-freebsd*
1584 FreeBSD/i386 i?86-*-freebsd*
1585 NetBSD/i386 i?86-*-netbsd*
1586 NetBSD/m68k m68*-*-netbsd*
1587 NetBSD/sparc sparc-*-netbsd*
1588 OpenBSD/amd64 x86_64-*-openbsd*
1589 OpenBSD/i386 i?86-*-openbsd*
1590 OpenBSD/m68k m68*-openbsd*
1591 OpenBSD/sparc sparc-*-openbsd*
1593 * Signal trampoline code overhauled
1595 Many generic problems with GDB's signal handling code have been fixed.
1596 These include: backtraces through non-contiguous stacks; recognition
1597 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1598 call; backtrace through a signal trampoline; step into and out of
1599 signal handlers; and single-stepping in the signal trampoline.
1601 Please note that kernel bugs are a limiting factor here. These
1602 features have been shown to work on an s390 GNU/Linux system that
1603 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1605 * Cygwin support for DWARF 2 added.
1607 * New native configurations
1609 GNU/Linux/hppa hppa*-*-linux*
1610 OpenBSD/hppa hppa*-*-openbsd*
1611 OpenBSD/m68k m68*-*-openbsd*
1612 OpenBSD/m88k m88*-*-openbsd*
1613 OpenBSD/powerpc powerpc-*-openbsd*
1614 NetBSD/vax vax-*-netbsd*
1615 OpenBSD/vax vax-*-openbsd*
1617 * END-OF-LIFE frame compatibility module
1619 GDB's internal frame infrastructure has been completely rewritten.
1620 The new infrastructure making it possible to support key new features
1621 including DWARF 2 Call Frame Information. To aid in the task of
1622 migrating old configurations to this new infrastructure, a
1623 compatibility module, that allowed old configurations to continue to
1624 work, was also included.
1626 GDB 6.2 will be the last release to include this frame compatibility
1627 module. This change directly impacts the following configurations:
1637 Unless there is activity to revive these configurations, they will be
1638 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1640 * REMOVED configurations and files
1642 Sun 3, running SunOS 3 m68*-*-sunos3*
1643 Sun 3, running SunOS 4 m68*-*-sunos4*
1644 Sun 2, running SunOS 3 m68000-*-sunos3*
1645 Sun 2, running SunOS 4 m68000-*-sunos4*
1646 Motorola 680x0 running LynxOS m68*-*-lynxos*
1647 AT&T 3b1/Unix pc m68*-att-*
1648 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1649 decstation mips-dec-* mips-little-*
1650 riscos mips-*-riscos* mips-*-sysv*
1651 sonymips mips-sony-*
1652 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1654 *** Changes in GDB 6.1.1:
1656 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1658 The TUI (Text-mode User Interface) is now built as part of a default
1659 GDB configuration. It is enabled by either selecting the TUI with the
1660 command line option "-i=tui" or by running the separate "gdbtui"
1661 program. For more information on the TUI, see the manual "Debugging
1664 * Pending breakpoint support (also included in GDB 6.1)
1666 Support has been added to allow you to specify breakpoints in shared
1667 libraries that have not yet been loaded. If a breakpoint location
1668 cannot be found, and the "breakpoint pending" option is set to auto,
1669 GDB queries you if you wish to make the breakpoint pending on a future
1670 shared-library load. If and when GDB resolves the breakpoint symbol,
1671 the pending breakpoint is removed as one or more regular breakpoints
1674 Pending breakpoints are very useful for GCJ Java debugging.
1676 * Fixed ISO-C build problems
1678 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1679 non ISO-C code that stopped them being built using a more strict ISO-C
1680 compiler (e.g., IBM's C compiler).
1682 * Fixed build problem on IRIX 5
1684 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1685 wasn't able to compile compile on an IRIX 5 system.
1687 * Added execute permission to gdb/gdbserver/configure
1689 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1690 permission. This bug would cause configure to fail on a number of
1691 systems (Solaris, IRIX). Ref: server/519.
1693 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1695 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1696 has been updated to use constant array sizes.
1698 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1700 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1701 its generated DWARF Call Frame Info. This encoding was causing GDB to
1702 panic, that panic has been fixed. Ref: gdb/1628.
1704 * Fixed a problem when examining parameters in shared library code.
1706 When examining parameters in optimized shared library code generated
1707 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1708 not available''. GDB now correctly displays the variable's value.
1710 *** Changes in GDB 6.1:
1712 * Removed --with-mmalloc
1714 Support for the mmalloc memory manager has been removed, as it
1715 conflicted with the internal gdb byte cache.
1717 * Changes in AMD64 configurations
1719 The AMD64 target now includes the %cs and %ss registers. As a result
1720 the AMD64 remote protocol has changed; this affects the floating-point
1721 and SSE registers. If you rely on those registers for your debugging,
1722 you should upgrade gdbserver on the remote side.
1724 * Revised SPARC target
1726 The SPARC target has been completely revised, incorporating the
1727 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1728 support for LynxOS and SunOS 4 has been dropped. Calling functions
1729 from within GDB on operating systems with a non-executable stack
1730 (Solaris, OpenBSD) now works.
1734 GDB has a new C++ demangler which does a better job on the mangled
1735 names generated by current versions of g++. It also runs faster, so
1736 with this and other changes gdb should now start faster on large C++
1739 * DWARF 2 Location Expressions
1741 GDB support for location expressions has been extended to support function
1742 arguments and frame bases. Older versions of GDB could crash when they
1745 * C++ nested types and namespaces
1747 GDB's support for nested types and namespaces in C++ has been
1748 improved, especially if you use the DWARF 2 debugging format. (This
1749 is the default for recent versions of GCC on most platforms.)
1750 Specifically, if you have a class "Inner" defined within a class or
1751 namespace "Outer", then GDB realizes that the class's name is
1752 "Outer::Inner", not simply "Inner". This should greatly reduce the
1753 frequency of complaints about not finding RTTI symbols. In addition,
1754 if you are stopped at inside of a function defined within a namespace,
1755 GDB modifies its name lookup accordingly.
1757 * New native configurations
1759 NetBSD/amd64 x86_64-*-netbsd*
1760 OpenBSD/amd64 x86_64-*-openbsd*
1761 OpenBSD/alpha alpha*-*-openbsd*
1762 OpenBSD/sparc sparc-*-openbsd*
1763 OpenBSD/sparc64 sparc64-*-openbsd*
1765 * New debugging protocols
1767 M32R with SDI protocol m32r-*-elf*
1769 * "set prompt-escape-char" command deleted.
1771 The command "set prompt-escape-char" has been deleted. This command,
1772 and its very obscure effet on GDB's prompt, was never documented,
1773 tested, nor mentioned in the NEWS file.
1775 * OBSOLETE configurations and files
1777 Configurations that have been declared obsolete in this release have
1778 been commented out. Unless there is activity to revive these
1779 configurations, the next release of GDB will have their sources
1780 permanently REMOVED.
1782 Sun 3, running SunOS 3 m68*-*-sunos3*
1783 Sun 3, running SunOS 4 m68*-*-sunos4*
1784 Sun 2, running SunOS 3 m68000-*-sunos3*
1785 Sun 2, running SunOS 4 m68000-*-sunos4*
1786 Motorola 680x0 running LynxOS m68*-*-lynxos*
1787 AT&T 3b1/Unix pc m68*-att-*
1788 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1789 decstation mips-dec-* mips-little-*
1790 riscos mips-*-riscos* mips-*-sysv*
1791 sonymips mips-sony-*
1792 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1794 * REMOVED configurations and files
1796 SGI Irix-4.x mips-sgi-irix4 or iris4
1797 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1798 Z8000 simulator z8k-zilog-none or z8ksim
1799 Matsushita MN10200 w/simulator mn10200-*-*
1800 H8/500 simulator h8500-hitachi-hms or h8500hms
1801 HP/PA running BSD hppa*-*-bsd*
1802 HP/PA running OSF/1 hppa*-*-osf*
1803 HP/PA Pro target hppa*-*-pro*
1804 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1805 386BSD i[3456]86-*-bsd*
1806 Sequent family i[3456]86-sequent-sysv4*
1807 i[3456]86-sequent-sysv*
1808 i[3456]86-sequent-bsd*
1809 SPARC running LynxOS sparc-*-lynxos*
1810 SPARC running SunOS 4 sparc-*-sunos4*
1811 Tsqware Sparclet sparclet-*-*
1812 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1814 *** Changes in GDB 6.0:
1818 Support for debugging the Objective-C programming language has been
1819 integrated into GDB.
1821 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1823 DWARF 2's Call Frame Information makes available compiler generated
1824 information that more exactly describes the program's run-time stack.
1825 By using this information, GDB is able to provide more robust stack
1828 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1829 have been updated to use a new backtrace mechanism which includes
1830 DWARF 2 CFI support.
1834 GDB's remote protocol has been extended to include support for hosted
1835 file I/O (where the remote target uses GDB's file system). See GDB's
1836 remote protocol documentation for details.
1838 * All targets using the new architecture framework.
1840 All of GDB's targets have been updated to use the new internal
1841 architecture framework. The way is now open for future GDB releases
1842 to include cross-architecture native debugging support (i386 on amd64,
1845 * GNU/Linux's Thread Local Storage (TLS)
1847 GDB now includes support for for the GNU/Linux implementation of
1848 per-thread variables.
1850 * GNU/Linux's Native POSIX Thread Library (NPTL)
1852 GDB's thread code has been updated to work with either the new
1853 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1855 * Separate debug info.
1857 GDB, in conjunction with BINUTILS, now supports a mechanism for
1858 automatically loading debug information from a separate file. Instead
1859 of shipping full debug and non-debug versions of system libraries,
1860 system integrators can now instead ship just the stripped libraries
1861 and optional debug files.
1863 * DWARF 2 Location Expressions
1865 DWARF 2 Location Expressions allow the compiler to more completely
1866 describe the location of variables (even in optimized code) to the
1869 GDB now includes preliminary support for location expressions (support
1870 for DW_OP_piece is still missing).
1874 A number of long standing bugs that caused GDB to die while starting a
1875 Java application have been fixed. GDB's Java support is now
1876 considered "useable".
1878 * GNU/Linux support for fork, vfork, and exec.
1880 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1881 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1884 * GDB supports logging output to a file
1886 There are two new commands, "set logging" and "show logging", which can be
1887 used to capture GDB's output to a file.
1889 * The meaning of "detach" has changed for gdbserver
1891 The "detach" command will now resume the application, as documented. To
1892 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1895 * d10v, m68hc11 `regs' command deprecated
1897 The `info registers' command has been updated so that it displays the
1898 registers using a format identical to the old `regs' command.
1902 A new command, "maint set profile on/off", has been added. This command can
1903 be used to enable or disable profiling while running GDB, to profile a
1904 session or a set of commands. In addition there is a new configure switch,
1905 "--enable-profiling", which will cause GDB to be compiled with profiling
1906 data, for more informative profiling results.
1908 * Default MI syntax changed to "mi2".
1910 The default MI (machine interface) syntax, enabled by the command line
1911 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1912 "mi1", can be enabled by specifying the option "-i=mi1".
1914 Support for the original "mi0" syntax (included in GDB 5.0) has been
1917 Fix for gdb/192: removed extraneous space when displaying frame level.
1918 Fix for gdb/672: update changelist is now output in mi list format.
1919 Fix for gdb/702: a -var-assign that updates the value now shows up
1920 in a subsequent -var-update.
1922 * New native configurations.
1924 FreeBSD/amd64 x86_64-*-freebsd*
1926 * Multi-arched targets.
1928 HP/PA HPUX11 hppa*-*-hpux*
1929 Renesas M32R/D w/simulator m32r-*-elf*
1931 * OBSOLETE configurations and files
1933 Configurations that have been declared obsolete in this release have
1934 been commented out. Unless there is activity to revive these
1935 configurations, the next release of GDB will have their sources
1936 permanently REMOVED.
1938 Z8000 simulator z8k-zilog-none or z8ksim
1939 Matsushita MN10200 w/simulator mn10200-*-*
1940 H8/500 simulator h8500-hitachi-hms or h8500hms
1941 HP/PA running BSD hppa*-*-bsd*
1942 HP/PA running OSF/1 hppa*-*-osf*
1943 HP/PA Pro target hppa*-*-pro*
1944 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1945 Sequent family i[3456]86-sequent-sysv4*
1946 i[3456]86-sequent-sysv*
1947 i[3456]86-sequent-bsd*
1948 Tsqware Sparclet sparclet-*-*
1949 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1951 * REMOVED configurations and files
1954 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1955 IBM AIX PS/2 i[3456]86-*-aix
1956 i386 running Mach 3.0 i[3456]86-*-mach3*
1957 i386 running Mach i[3456]86-*-mach*
1958 i386 running OSF/1 i[3456]86-*osf1mk*
1959 HP/Apollo 68k Family m68*-apollo*-sysv*,
1961 m68*-hp-bsd*, m68*-hp-hpux*
1962 Argonaut Risc Chip (ARC) arc-*-*
1963 Mitsubishi D30V d30v-*-*
1964 Fujitsu FR30 fr30-*-elf*
1965 OS/9000 i[34]86-*-os9k
1966 I960 with MON960 i960-*-coff
1968 * MIPS $fp behavior changed
1970 The convenience variable $fp, for the MIPS, now consistently returns
1971 the address of the current frame's base. Previously, depending on the
1972 context, $fp could refer to either $sp or the current frame's base
1973 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1974 The GNU Source-Level Debugger''.
1976 *** Changes in GDB 5.3:
1978 * GNU/Linux shared library multi-threaded performance improved.
1980 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1981 `/proc', in preference to `ptrace' for memory reads. This may result
1982 in an improvement in the start-up time of multi-threaded, shared
1983 library applications when run under GDB. One GDB user writes: ``loads
1984 shared libs like mad''.
1986 * ``gdbserver'' now supports multi-threaded applications on some targets
1988 Support for debugging multi-threaded applications which use
1989 the GNU/Linux LinuxThreads package has been added for
1990 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1991 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1993 * GDB now supports C/C++ preprocessor macros.
1995 GDB now expands preprocessor macro invocations in C/C++ expressions,
1996 and provides various commands for showing macro definitions and how
1999 The new command `macro expand EXPRESSION' expands any macro
2000 invocations in expression, and shows the result.
2002 The new command `show macro MACRO-NAME' shows the definition of the
2003 macro named MACRO-NAME, and where it was defined.
2005 Most compilers don't include information about macros in the debugging
2006 information by default. In GCC 3.1, for example, you need to compile
2007 your program with the options `-gdwarf-2 -g3'. If the macro
2008 information is present in the executable, GDB will read it.
2010 * Multi-arched targets.
2012 DEC Alpha (partial) alpha*-*-*
2013 DEC VAX (partial) vax-*-*
2015 National Semiconductor NS32000 (partial) ns32k-*-*
2016 Motorola 68000 (partial) m68k-*-*
2017 Motorola MCORE mcore-*-*
2021 Fujitsu FRV architecture added by Red Hat frv*-*-*
2024 * New native configurations
2026 Alpha NetBSD alpha*-*-netbsd*
2027 SH NetBSD sh*-*-netbsdelf*
2028 MIPS NetBSD mips*-*-netbsd*
2029 UltraSPARC NetBSD sparc64-*-netbsd*
2031 * OBSOLETE configurations and files
2033 Configurations that have been declared obsolete in this release have
2034 been commented out. Unless there is activity to revive these
2035 configurations, the next release of GDB will have their sources
2036 permanently REMOVED.
2038 Mitsubishi D30V d30v-*-*
2039 OS/9000 i[34]86-*-os9k
2040 IBM AIX PS/2 i[3456]86-*-aix
2041 Fujitsu FR30 fr30-*-elf*
2042 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2043 Argonaut Risc Chip (ARC) arc-*-*
2044 i386 running Mach 3.0 i[3456]86-*-mach3*
2045 i386 running Mach i[3456]86-*-mach*
2046 i386 running OSF/1 i[3456]86-*osf1mk*
2047 HP/Apollo 68k Family m68*-apollo*-sysv*,
2049 m68*-hp-bsd*, m68*-hp-hpux*
2050 I960 with MON960 i960-*-coff
2052 * OBSOLETE languages
2054 CHILL, a Pascal like language used by telecommunications companies.
2056 * REMOVED configurations and files
2058 AMD 29k family via UDI a29k-amd-udi, udi29k
2059 A29K VxWorks a29k-*-vxworks
2060 AMD 29000 embedded, using EBMON a29k-none-none
2061 AMD 29000 embedded with COFF a29k-none-coff
2062 AMD 29000 embedded with a.out a29k-none-aout
2064 testsuite/gdb.hp/gdb.threads-hp/ directory
2066 * New command "set max-user-call-depth <nnn>"
2068 This command allows the user to limit the call depth of user-defined
2069 commands. The default is 1024.
2071 * Changes in FreeBSD/i386 native debugging.
2073 Support for the "generate-core-file" has been added.
2075 * New commands "dump", "append", and "restore".
2077 These commands allow data to be copied from target memory
2078 to a bfd-format or binary file (dump and append), and back
2079 from a file into memory (restore).
2081 * Improved "next/step" support on multi-processor Alpha Tru64.
2083 The previous single-step mechanism could cause unpredictable problems,
2084 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2085 of a software single-step mechanism prevents this.
2087 *** Changes in GDB 5.2.1:
2095 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2096 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2097 Fix, by Joel Brobecker imported from mainline.
2099 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2100 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2101 Fix, by Fred Fish, imported from mainline.
2103 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2104 Surprisingly enough, it works now.
2105 By Michal Ludvig, imported from mainline.
2107 i386 hardware watchpoint support:
2108 avoid misses on second run for some targets.
2109 By Pierre Muller, imported from mainline.
2111 *** Changes in GDB 5.2:
2113 * New command "set trust-readonly-sections on[off]".
2115 This command is a hint that tells gdb that read-only sections
2116 really are read-only (ie. that their contents will not change).
2117 In this mode, gdb will go to the object file rather than the
2118 target to read memory from read-only sections (such as ".text").
2119 This can be a significant performance improvement on some
2120 (notably embedded) targets.
2122 * New command "generate-core-file" (or "gcore").
2124 This new gdb command allows the user to drop a core file of the child
2125 process state at any time. So far it's been implemented only for
2126 GNU/Linux and Solaris, but should be relatively easily ported to other
2127 hosts. Argument is core file name (defaults to core.<pid>).
2129 * New command line option
2131 GDB now accepts --pid or -p followed by a process id.
2133 * Change in command line behavior -- corefiles vs. process ids.
2135 There is a subtle behavior in the way in which GDB handles
2136 command line arguments. The first non-flag argument is always
2137 a program to debug, but the second non-flag argument may either
2138 be a corefile or a process id. Previously, GDB would attempt to
2139 open the second argument as a corefile, and if that failed, would
2140 issue a superfluous error message and then attempt to attach it as
2141 a process. Now, if the second argument begins with a non-digit,
2142 it will be treated as a corefile. If it begins with a digit,
2143 GDB will attempt to attach it as a process, and if no such process
2144 is found, will then attempt to open it as a corefile.
2146 * Changes in ARM configurations.
2148 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2149 configuration is fully multi-arch.
2151 * New native configurations
2153 ARM NetBSD arm*-*-netbsd*
2154 x86 OpenBSD i[3456]86-*-openbsd*
2155 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2156 Sparc64 running FreeBSD sparc64-*-freebsd*
2160 Sanyo XStormy16 xstormy16-elf
2162 * OBSOLETE configurations and files
2164 Configurations that have been declared obsolete in this release have
2165 been commented out. Unless there is activity to revive these
2166 configurations, the next release of GDB will have their sources
2167 permanently REMOVED.
2169 AMD 29k family via UDI a29k-amd-udi, udi29k
2170 A29K VxWorks a29k-*-vxworks
2171 AMD 29000 embedded, using EBMON a29k-none-none
2172 AMD 29000 embedded with COFF a29k-none-coff
2173 AMD 29000 embedded with a.out a29k-none-aout
2175 testsuite/gdb.hp/gdb.threads-hp/ directory
2177 * REMOVED configurations and files
2179 TI TMS320C80 tic80-*-*
2181 PowerPC Solaris powerpcle-*-solaris*
2182 PowerPC Windows NT powerpcle-*-cygwin32
2183 PowerPC Netware powerpc-*-netware*
2184 Harris/CXUX m88k m88*-harris-cxux*
2185 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2186 ns32k-utek-sysv* ns32k-utek-*
2187 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2188 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2189 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2190 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2191 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2193 * Changes to command line processing
2195 The new `--args' feature can be used to specify command-line arguments
2196 for the inferior from gdb's command line.
2198 * Changes to key bindings
2200 There is a new `operate-and-get-next' function bound to `C-o'.
2202 *** Changes in GDB 5.1.1
2204 Fix compile problem on DJGPP.
2206 Fix a problem with floating-point registers on the i386 being
2209 Fix to stop GDB crashing on .debug_str debug info.
2211 Numerous documentation fixes.
2213 Numerous testsuite fixes.
2215 *** Changes in GDB 5.1:
2217 * New native configurations
2219 Alpha FreeBSD alpha*-*-freebsd*
2220 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2221 MIPS GNU/Linux mips*-*-linux*
2222 MIPS SGI Irix 6.x mips*-sgi-irix6*
2223 ia64 AIX ia64-*-aix*
2224 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2228 Motorola 68HC11 and 68HC12 m68hc11-elf
2230 UltraSparc running GNU/Linux sparc64-*-linux*
2232 * OBSOLETE configurations and files
2234 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2235 Harris/CXUX m88k m88*-harris-cxux*
2236 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2237 ns32k-utek-sysv* ns32k-utek-*
2238 TI TMS320C80 tic80-*-*
2240 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2241 PowerPC Solaris powerpcle-*-solaris*
2242 PowerPC Windows NT powerpcle-*-cygwin32
2243 PowerPC Netware powerpc-*-netware*
2244 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2245 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2246 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2247 Apple Macintosh (MPW) host N/A
2249 stuff.c (Program to stuff files into a specially prepared space in kdb)
2250 kdb-start.c (Main loop for the standalone kernel debugger)
2252 Configurations that have been declared obsolete in this release have
2253 been commented out. Unless there is activity to revive these
2254 configurations, the next release of GDB will have their sources
2255 permanently REMOVED.
2257 * REMOVED configurations and files
2259 Altos 3068 m68*-altos-*
2260 Convex c1-*-*, c2-*-*
2262 ARM RISCix arm-*-* (as host)
2266 * GDB has been converted to ISO C.
2268 GDB's source code has been converted to ISO C. In particular, the
2269 sources are fully protoized, and rely on standard headers being
2274 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2276 * The MI enabled by default.
2278 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2279 revised and enabled by default. Packages which use GDB as a debugging
2280 engine behind a UI or another front end are encouraged to switch to
2281 using the GDB/MI interface, instead of the old annotations interface
2282 which is now deprecated.
2284 * Support for debugging Pascal programs.
2286 GDB now includes support for debugging Pascal programs. The following
2287 main features are supported:
2289 - Pascal-specific data types such as sets;
2291 - automatic recognition of Pascal sources based on file-name
2294 - Pascal-style display of data types, variables, and functions;
2296 - a Pascal expression parser.
2298 However, some important features are not yet supported.
2300 - Pascal string operations are not supported at all;
2302 - there are some problems with boolean types;
2304 - Pascal type hexadecimal constants are not supported
2305 because they conflict with the internal variables format;
2307 - support for Pascal objects and classes is not full yet;
2309 - unlike Pascal, GDB is case-sensitive for symbol names.
2311 * Changes in completion.
2313 Commands such as `shell', `run' and `set args', which pass arguments
2314 to inferior programs, now complete on file names, similar to what
2315 users expect at the shell prompt.
2317 Commands which accept locations, such as `disassemble', `print',
2318 `breakpoint', `until', etc. now complete on filenames as well as
2319 program symbols. Thus, if you type "break foob TAB", and the source
2320 files linked into the programs include `foobar.c', that file name will
2321 be one of the candidates for completion. However, file names are not
2322 considered for completion after you typed a colon that delimits a file
2323 name from a name of a function in that file, as in "break foo.c:bar".
2325 `set demangle-style' completes on available demangling styles.
2327 * New platform-independent commands:
2329 It is now possible to define a post-hook for a command as well as a
2330 hook that runs before the command. For more details, see the
2331 documentation of `hookpost' in the GDB manual.
2333 * Changes in GNU/Linux native debugging.
2335 Support for debugging multi-threaded programs has been completely
2336 revised for all platforms except m68k and sparc. You can now debug as
2337 many threads as your system allows you to have.
2339 Attach/detach is supported for multi-threaded programs.
2341 Support for SSE registers was added for x86. This doesn't work for
2342 multi-threaded programs though.
2344 * Changes in MIPS configurations.
2346 Multi-arch support is enabled for all MIPS configurations.
2348 GDB can now be built as native debugger on SGI Irix 6.x systems for
2349 debugging n32 executables. (Debugging 64-bit executables is not yet
2352 * Unified support for hardware watchpoints in all x86 configurations.
2354 Most (if not all) native x86 configurations support hardware-assisted
2355 breakpoints and watchpoints in a unified manner. This support
2356 implements debug register sharing between watchpoints, which allows to
2357 put a virtually infinite number of watchpoints on the same address,
2358 and also supports watching regions up to 16 bytes with several debug
2361 The new maintenance command `maintenance show-debug-regs' toggles
2362 debugging print-outs in functions that insert, remove, and test
2363 watchpoints and hardware breakpoints.
2365 * Changes in the DJGPP native configuration.
2367 New command ``info dos sysinfo'' displays assorted information about
2368 the CPU, OS, memory, and DPMI server.
2370 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2371 display information about segment descriptors stored in GDT, LDT, and
2374 New commands ``info dos pde'' and ``info dos pte'' display entries
2375 from Page Directory and Page Tables (for now works with CWSDPMI only).
2376 New command ``info dos address-pte'' displays the Page Table entry for
2377 a given linear address.
2379 GDB can now pass command lines longer than 126 characters to the
2380 program being debugged (requires an update to the libdbg.a library
2381 which is part of the DJGPP development kit).
2383 DWARF2 debug info is now supported.
2385 It is now possible to `step' and `next' through calls to `longjmp'.
2387 * Changes in documentation.
2389 All GDB documentation was converted to GFDL, the GNU Free
2390 Documentation License.
2392 Tracepoints-related commands are now fully documented in the GDB
2395 TUI, the Text-mode User Interface, is now documented in the manual.
2397 Tracepoints-related commands are now fully documented in the GDB
2400 The "GDB Internals" manual now has an index. It also includes
2401 documentation of `ui_out' functions, GDB coding standards, x86
2402 hardware watchpoints, and memory region attributes.
2404 * GDB's version number moved to ``version.in''
2406 The Makefile variable VERSION has been replaced by the file
2407 ``version.in''. People creating GDB distributions should update the
2408 contents of this file.
2412 GUD support is now a standard part of the EMACS distribution.
2414 *** Changes in GDB 5.0:
2416 * Improved support for debugging FP programs on x86 targets
2418 Unified and much-improved support for debugging floating-point
2419 programs on all x86 targets. In particular, ``info float'' now
2420 displays the FP registers in the same format on all x86 targets, with
2421 greater level of detail.
2423 * Improvements and bugfixes in hardware-assisted watchpoints
2425 It is now possible to watch array elements, struct members, and
2426 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2427 on x86 targets no longer erroneously trigger when the address is
2430 * Improvements in the native DJGPP version of GDB
2432 The distribution now includes all the scripts and auxiliary files
2433 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2434 machines ``out of the box''.
2436 The DJGPP version can now debug programs that use signals. It is
2437 possible to catch signals that happened in the debuggee, deliver
2438 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2439 would kill the program being debugged.) Programs that hook hardware
2440 interrupts (keyboard, timer, etc.) can also be debugged.
2442 It is now possible to debug DJGPP programs that redirect their
2443 standard handles or switch them to raw (as opposed to cooked) mode, or
2444 even close them. The command ``run < foo > bar'' works as expected,
2445 and ``info terminal'' reports useful information about the debuggee's
2446 terminal, including raw/cooked mode, redirection, etc.
2448 The DJGPP version now uses termios functions for console I/O, which
2449 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2452 DOS-style file names with drive letters are now fully supported by
2455 It is now possible to debug DJGPP programs that switch their working
2456 directory. It is also possible to rerun the debuggee any number of
2457 times without restarting GDB; thus, you can use the same setup,
2458 breakpoints, etc. for many debugging sessions.
2460 * New native configurations
2462 ARM GNU/Linux arm*-*-linux*
2463 PowerPC GNU/Linux powerpc-*-linux*
2467 Motorola MCore mcore-*-*
2468 x86 VxWorks i[3456]86-*-vxworks*
2469 PowerPC VxWorks powerpc-*-vxworks*
2470 TI TMS320C80 tic80-*-*
2472 * OBSOLETE configurations
2474 Altos 3068 m68*-altos-*
2475 Convex c1-*-*, c2-*-*
2477 ARM RISCix arm-*-* (as host)
2480 Configurations that have been declared obsolete will be commented out,
2481 but the code will be left in place. If there is no activity to revive
2482 these configurations before the next release of GDB, the sources will
2483 be permanently REMOVED.
2485 * Gould support removed
2487 Support for the Gould PowerNode and NP1 has been removed.
2489 * New features for SVR4
2491 On SVR4 native platforms (such as Solaris), if you attach to a process
2492 without first loading a symbol file, GDB will now attempt to locate and
2493 load symbols from the running process's executable file.
2495 * Many C++ enhancements
2497 C++ support has been greatly improved. Overload resolution now works properly
2498 in almost all cases. RTTI support is on the way.
2500 * Remote targets can connect to a sub-program
2502 A popen(3) style serial-device has been added. This device starts a
2503 sub-process (such as a stand-alone simulator) and then communicates
2504 with that. The sub-program to run is specified using the syntax
2505 ``|<program> <args>'' vis:
2507 (gdb) set remotedebug 1
2508 (gdb) target extended-remote |mn10300-elf-sim program-args
2510 * MIPS 64 remote protocol
2512 A long standing bug in the mips64 remote protocol where by GDB
2513 expected certain 32 bit registers (ex SR) to be transfered as 32
2514 instead of 64 bits has been fixed.
2516 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2517 added to provide backward compatibility with older versions of GDB.
2519 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2521 The command ``set remotebinarydownload'' command has been replaced by
2522 ``set remote X-packet''. Other commands in ``set remote'' family
2523 include ``set remote P-packet''.
2525 * Breakpoint commands accept ranges.
2527 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2528 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2529 ``tracepoint passcount'' also accepts a range of tracepoints.
2531 * ``apropos'' command added.
2533 The ``apropos'' command searches through command names and
2534 documentation strings, printing out matches, making it much easier to
2535 try to find a command that does what you are looking for.
2539 A new machine oriented interface (MI) has been added to GDB. This
2540 interface is designed for debug environments running GDB as a separate
2541 process. This is part of the long term libGDB project. See the
2542 "GDB/MI" chapter of the GDB manual for further information. It can be
2543 enabled by configuring with:
2545 .../configure --enable-gdbmi
2547 *** Changes in GDB-4.18:
2549 * New native configurations
2551 HP-UX 10.20 hppa*-*-hpux10.20
2552 HP-UX 11.x hppa*-*-hpux11.0*
2553 M68K GNU/Linux m68*-*-linux*
2557 Fujitsu FR30 fr30-*-elf*
2558 Intel StrongARM strongarm-*-*
2559 Mitsubishi D30V d30v-*-*
2561 * OBSOLETE configurations
2563 Gould PowerNode, NP1 np1-*-*, pn-*-*
2565 Configurations that have been declared obsolete will be commented out,
2566 but the code will be left in place. If there is no activity to revive
2567 these configurations before the next release of GDB, the sources will
2568 be permanently REMOVED.
2572 As a compatibility experiment, GDB's source files buildsym.h and
2573 buildsym.c have been converted to pure standard C, no longer
2574 containing any K&R compatibility code. We believe that all systems in
2575 use today either come with a standard C compiler, or have a GCC port
2576 available. If this is not true, please report the affected
2577 configuration to bug-gdb@gnu.org immediately. See the README file for
2578 information about getting a standard C compiler if you don't have one
2583 GDB now uses readline 2.2.
2585 * set extension-language
2587 You can now control the mapping between filename extensions and source
2588 languages by using the `set extension-language' command. For instance,
2589 you can ask GDB to treat .c files as C++ by saying
2590 set extension-language .c c++
2591 The command `info extensions' lists all of the recognized extensions
2592 and their associated languages.
2594 * Setting processor type for PowerPC and RS/6000
2596 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2597 you can use the `set processor' command to specify what variant of the
2598 PowerPC family you are debugging. The command
2602 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2603 following PowerPC and RS6000 variants:
2605 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2606 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2608 403GC IBM PowerPC 403GC
2609 505 Motorola PowerPC 505
2610 860 Motorola PowerPC 860 or 850
2611 601 Motorola PowerPC 601
2612 602 Motorola PowerPC 602
2613 603 Motorola/IBM PowerPC 603 or 603e
2614 604 Motorola PowerPC 604 or 604e
2615 750 Motorola/IBM PowerPC 750 or 750
2617 At the moment, this command just tells GDB what to name the
2618 special-purpose processor registers. Since almost all the affected
2619 registers are inaccessible to user-level programs, this command is
2620 only useful for remote debugging in its present form.
2624 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2625 more extensive support for HP-UX. Added features include shared
2626 library support, kernel threads and hardware watchpoints for 11.00,
2627 support for HP's ANSI C and C++ compilers, and a compatibility mode
2628 for xdb and dbx commands.
2632 HP's donation includes the new concept of catchpoints, which is a
2633 generalization of the old catch command. On HP-UX, it is now possible
2634 to catch exec, fork, and vfork, as well as library loading.
2636 This means that the existing catch command has changed; its first
2637 argument now specifies the type of catch to be set up. See the
2638 output of "help catch" for a list of catchpoint types.
2640 * Debugging across forks
2642 On HP-UX, you can choose which process to debug when a fork() happens
2647 HP has donated a curses-based terminal user interface (TUI). To get
2648 it, build with --enable-tui. Although this can be enabled for any
2649 configuration, at present it only works for native HP debugging.
2651 * GDB remote protocol additions
2653 A new protocol packet 'X' that writes binary data is now available.
2654 Default behavior is to try 'X', then drop back to 'M' if the stub
2655 fails to respond. The settable variable `remotebinarydownload'
2656 allows explicit control over the use of 'X'.
2658 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2659 full 64-bit address. The command
2661 set remoteaddresssize 32
2663 can be used to revert to the old behaviour. For existing remote stubs
2664 the change should not be noticed, as the additional address information
2667 In order to assist in debugging stubs, you may use the maintenance
2668 command `packet' to send any text string to the stub. For instance,
2670 maint packet heythere
2672 sends the packet "$heythere#<checksum>". Note that it is very easy to
2673 disrupt a debugging session by sending the wrong packet at the wrong
2676 The compare-sections command allows you to compare section data on the
2677 target to what is in the executable file without uploading or
2678 downloading, by comparing CRC checksums.
2680 * Tracing can collect general expressions
2682 You may now collect general expressions at tracepoints. This requires
2683 further additions to the target-side stub; see tracepoint.c and
2684 doc/agentexpr.texi for further details.
2686 * mask-address variable for Mips
2688 For Mips targets, you may control the zeroing of the upper 32 bits of
2689 a 64-bit address by entering `set mask-address on'. This is mainly
2690 of interest to users of embedded R4xxx and R5xxx processors.
2692 * Higher serial baud rates
2694 GDB's serial code now allows you to specify baud rates 57600, 115200,
2695 230400, and 460800 baud. (Note that your host system may not be able
2696 to achieve all of these rates.)
2700 The i960 configuration now includes an initial implementation of a
2701 builtin simulator, contributed by Jim Wilson.
2704 *** Changes in GDB-4.17:
2706 * New native configurations
2708 Alpha GNU/Linux alpha*-*-linux*
2709 Unixware 2.x i[3456]86-unixware2*
2710 Irix 6.x mips*-sgi-irix6*
2711 PowerPC GNU/Linux powerpc-*-linux*
2712 PowerPC Solaris powerpcle-*-solaris*
2713 Sparc GNU/Linux sparc-*-linux*
2714 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2718 Argonaut Risc Chip (ARC) arc-*-*
2719 Hitachi H8/300S h8300*-*-*
2720 Matsushita MN10200 w/simulator mn10200-*-*
2721 Matsushita MN10300 w/simulator mn10300-*-*
2722 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2723 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2724 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2725 Mitsubishi D10V w/simulator d10v-*-*
2726 Mitsubishi M32R/D w/simulator m32r-*-elf*
2727 Tsqware Sparclet sparclet-*-*
2728 NEC V850 w/simulator v850-*-*
2730 * New debugging protocols
2732 ARM with RDI protocol arm*-*-*
2733 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2734 DDB and LSI variants of PMON protocol mips*-*-*
2735 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2736 PowerPC with SDS protocol powerpc{,le}-*-eabi
2737 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2741 All configurations can now understand and use the DWARF 2 debugging
2742 format. The choice is automatic, if the symbol file contains DWARF 2
2747 GDB now includes basic Java language support. This support is
2748 only useful with Java compilers that produce native machine code.
2750 * solib-absolute-prefix and solib-search-path
2752 For SunOS and SVR4 shared libraries, you may now set the prefix for
2753 loading absolute shared library symbol files, and the search path for
2754 locating non-absolute shared library symbol files.
2756 * Live range splitting
2758 GDB can now effectively debug code for which GCC has performed live
2759 range splitting as part of its optimization. See gdb/doc/LRS for
2760 more details on the expected format of the stabs information.
2764 GDB's support for the GNU Hurd, including thread debugging, has been
2765 updated to work with current versions of the Hurd.
2769 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2770 instruction set. ARM GDB automatically detects when Thumb
2771 instructions are in use, and adjusts disassembly and backtracing
2776 GDB's MIPS target configurations now handle the MIP16 16-bit
2781 GDB now includes support for overlays; if an executable has been
2782 linked such that multiple sections are based at the same address, GDB
2783 will decide which section to use for symbolic info. You can choose to
2784 control the decision manually, using overlay commands, or implement
2785 additional target-side support and use "overlay load-target" to bring
2786 in the overlay mapping. Do "help overlay" for more detail.
2790 The command "info symbol <address>" displays information about
2791 the symbol at the specified address.
2795 The standard remote protocol now includes an extension that allows
2796 asynchronous collection and display of trace data. This requires
2797 extensive support in the target-side debugging stub. Tracing mode
2798 includes a new interaction mode in GDB and new commands: see the
2799 file tracepoint.c for more details.
2803 Configurations for embedded MIPS now include a simulator contributed
2804 by Cygnus Solutions. The simulator supports the instruction sets
2805 of most MIPS variants.
2809 Sparc configurations may now include the ERC32 simulator contributed
2810 by the European Space Agency. The simulator is not built into
2811 Sparc targets by default; configure with --enable-sim to include it.
2815 For target configurations that may include multiple variants of a
2816 basic architecture (such as MIPS and SH), you may now set the
2817 architecture explicitly. "set arch" sets, "info arch" lists
2818 the possible architectures.
2820 *** Changes in GDB-4.16:
2822 * New native configurations
2824 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2825 M68K NetBSD m68k-*-netbsd*
2826 PowerPC AIX 4.x powerpc-*-aix*
2827 PowerPC MacOS powerpc-*-macos*
2828 PowerPC Windows NT powerpcle-*-cygwin32
2829 RS/6000 AIX 4.x rs6000-*-aix4*
2833 ARM with RDP protocol arm-*-*
2834 I960 with MON960 i960-*-coff
2835 MIPS VxWorks mips*-*-vxworks*
2836 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2837 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2839 Matra Sparclet sparclet-*-*
2843 The powerpc-eabi configuration now includes the PSIM simulator,
2844 contributed by Andrew Cagney, with assistance from Mike Meissner.
2845 PSIM is a very elaborate model of the PowerPC, including not only
2846 basic instruction set execution, but also details of execution unit
2847 performance and I/O hardware. See sim/ppc/README for more details.
2851 GDB now works with Solaris 2.5.
2853 * Windows 95/NT native
2855 GDB will now work as a native debugger on Windows 95 and Windows NT.
2856 To build it from source, you must use the "gnu-win32" environment,
2857 which uses a DLL to emulate enough of Unix to run the GNU tools.
2858 Further information, binaries, and sources are available at
2859 ftp.cygnus.com, under pub/gnu-win32.
2861 * dont-repeat command
2863 If a user-defined command includes the command `dont-repeat', then the
2864 command will not be repeated if the user just types return. This is
2865 useful if the command is time-consuming to run, so that accidental
2866 extra keystrokes don't run the same command many times.
2868 * Send break instead of ^C
2870 The standard remote protocol now includes an option to send a break
2871 rather than a ^C to the target in order to interrupt it. By default,
2872 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2874 * Remote protocol timeout
2876 The standard remote protocol includes a new variable `remotetimeout'
2877 that allows you to set the number of seconds before GDB gives up trying
2878 to read from the target. The default value is 2.
2880 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2882 By default GDB will automatically keep track of objects as they are
2883 loaded and unloaded by the dynamic linker. By using the command `set
2884 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2885 when shared library events occur, thus allowing you to set breakpoints
2886 in shared libraries which are explicitly loaded by the inferior.
2888 Note this feature does not work on hpux8. On hpux9 you must link
2889 /usr/lib/end.o into your program. This feature should work
2890 automatically on hpux10.
2892 * Irix 5.x hardware watchpoint support
2894 Irix 5 configurations now support the use of hardware watchpoints.
2896 * Mips protocol "SYN garbage limit"
2898 When debugging a Mips target using the `target mips' protocol, you
2899 may set the number of characters that GDB will ignore by setting
2900 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2901 every character. The default value is 1050.
2903 * Recording and replaying remote debug sessions
2905 If you set `remotelogfile' to the name of a file, gdb will write to it
2906 a recording of a remote debug session. This recording may then be
2907 replayed back to gdb using "gdbreplay". See gdbserver/README for
2908 details. This is useful when you have a problem with GDB while doing
2909 remote debugging; you can make a recording of the session and send it
2910 to someone else, who can then recreate the problem.
2912 * Speedups for remote debugging
2914 GDB includes speedups for downloading and stepping MIPS systems using
2915 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2916 and more efficient S-record downloading.
2918 * Memory use reductions and statistics collection
2920 GDB now uses less memory and reports statistics about memory usage.
2921 Try the `maint print statistics' command, for example.
2923 *** Changes in GDB-4.15:
2925 * Psymtabs for XCOFF
2927 The symbol reader for AIX GDB now uses partial symbol tables. This
2928 can greatly improve startup time, especially for large executables.
2930 * Remote targets use caching
2932 Remote targets now use a data cache to speed up communication with the
2933 remote side. The data cache could lead to incorrect results because
2934 it doesn't know about volatile variables, thus making it impossible to
2935 debug targets which use memory mapped I/O devices. `set remotecache
2936 off' turns the the data cache off.
2938 * Remote targets may have threads
2940 The standard remote protocol now includes support for multiple threads
2941 in the target system, using new protocol commands 'H' and 'T'. See
2942 gdb/remote.c for details.
2946 If GDB is configured with `--enable-netrom', then it will include
2947 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2948 acts as though it is a bank of ROM on the target board, but you can
2949 write into it over the network. GDB's support consists only of
2950 support for fast loading into the emulated ROM; to debug, you must use
2951 another protocol, such as standard remote protocol. The usual
2952 sequence is something like
2954 target nrom <netrom-hostname>
2956 target remote <netrom-hostname>:1235
2960 GDB now includes support for the Apple Macintosh, as a host only. It
2961 may be run as either an MPW tool or as a standalone application, and
2962 it can debug through the serial port. All the usual GDB commands are
2963 available, but to the target command, you must supply "serial" as the
2964 device type instead of "/dev/ttyXX". See mpw-README in the main
2965 directory for more information on how to build. The MPW configuration
2966 scripts */mpw-config.in support only a few targets, and only the
2967 mips-idt-ecoff target has been tested.
2971 GDB configuration now uses autoconf. This is not user-visible,
2972 but does simplify configuration and building.
2976 GDB now supports hpux10.
2978 *** Changes in GDB-4.14:
2980 * New native configurations
2982 x86 FreeBSD i[345]86-*-freebsd
2983 x86 NetBSD i[345]86-*-netbsd
2984 NS32k NetBSD ns32k-*-netbsd
2985 Sparc NetBSD sparc-*-netbsd
2989 A29K VxWorks a29k-*-vxworks
2990 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2991 CPU32 EST-300 emulator m68*-*-est*
2992 PowerPC ELF powerpc-*-elf
2995 * Alpha OSF/1 support for procfs
2997 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2998 possible to attach to running processes. As the mounting of the /proc
2999 filesystem is optional on the Alpha, GDB automatically determines
3000 the availability of /proc during startup. This can lead to problems
3001 if /proc is unmounted after GDB has been started.
3003 * Arguments to user-defined commands
3005 User commands may accept up to 10 arguments separated by whitespace.
3006 Arguments are accessed within the user command via $arg0..$arg9. A
3009 print $arg0 + $arg1 + $arg2
3011 To execute the command use:
3014 Defines the command "adder" which prints the sum of its three arguments.
3015 Note the arguments are text substitutions, so they may reference variables,
3016 use complex expressions, or even perform inferior function calls.
3018 * New `if' and `while' commands
3020 This makes it possible to write more sophisticated user-defined
3021 commands. Both commands take a single argument, which is the
3022 expression to evaluate, and must be followed by the commands to
3023 execute, one per line, if the expression is nonzero, the list being
3024 terminated by the word `end'. The `if' command list may include an
3025 `else' word, which causes the following commands to be executed only
3026 if the expression is zero.
3028 * Fortran source language mode
3030 GDB now includes partial support for Fortran 77. It will recognize
3031 Fortran programs and can evaluate a subset of Fortran expressions, but
3032 variables and functions may not be handled correctly. GDB will work
3033 with G77, but does not yet know much about symbols emitted by other
3036 * Better HPUX support
3038 Most debugging facilities now work on dynamic executables for HPPAs
3039 running hpux9 or later. You can attach to running dynamically linked
3040 processes, but by default the dynamic libraries will be read-only, so
3041 for instance you won't be able to put breakpoints in them. To change
3042 that behavior do the following before running the program:
3048 This will cause the libraries to be mapped private and read-write.
3049 To revert to the normal behavior, do this:
3055 You cannot set breakpoints or examine data in the library until after
3056 the library is loaded if the function/data symbols do not have
3059 GDB can now also read debug symbols produced by the HP C compiler on
3060 HPPAs (sorry, no C++, Fortran or 68k support).
3062 * Target byte order now dynamically selectable
3064 You can choose which byte order to use with a target system, via the
3065 commands "set endian big" and "set endian little", and you can see the
3066 current setting by using "show endian". You can also give the command
3067 "set endian auto", in which case GDB will use the byte order
3068 associated with the executable. Currently, only embedded MIPS
3069 configurations support dynamic selection of target byte order.
3071 * New DOS host serial code
3073 This version uses DPMI interrupts to handle buffered I/O, so you
3074 no longer need to run asynctsr when debugging boards connected to
3077 *** Changes in GDB-4.13:
3079 * New "complete" command
3081 This lists all the possible completions for the rest of the line, if it
3082 were to be given as a command itself. This is intended for use by emacs.
3084 * Trailing space optional in prompt
3086 "set prompt" no longer adds a space for you after the prompt you set. This
3087 allows you to set a prompt which ends in a space or one that does not.
3089 * Breakpoint hit counts
3091 "info break" now displays a count of the number of times the breakpoint
3092 has been hit. This is especially useful in conjunction with "ignore"; you
3093 can ignore a large number of breakpoint hits, look at the breakpoint info
3094 to see how many times the breakpoint was hit, then run again, ignoring one
3095 less than that number, and this will get you quickly to the last hit of
3098 * Ability to stop printing at NULL character
3100 "set print null-stop" will cause GDB to stop printing the characters of
3101 an array when the first NULL is encountered. This is useful when large
3102 arrays actually contain only short strings.
3104 * Shared library breakpoints
3106 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3107 breakpoints in shared libraries before the executable is run.
3109 * Hardware watchpoints
3111 There is a new hardware breakpoint for the watch command for sparclite
3112 targets. See gdb/sparclite/hw_breakpoint.note.
3114 Hardware watchpoints are also now supported under GNU/Linux.
3118 Annotations have been added. These are for use with graphical interfaces,
3119 and are still experimental. Currently only gdba.el uses these.
3121 * Improved Irix 5 support
3123 GDB now works properly with Irix 5.2.
3125 * Improved HPPA support
3127 GDB now works properly with the latest GCC and GAS.
3129 * New native configurations
3131 Sequent PTX4 i[34]86-sequent-ptx4
3132 HPPA running OSF/1 hppa*-*-osf*
3133 Atari TT running SVR4 m68*-*-sysv4*
3134 RS/6000 LynxOS rs6000-*-lynxos*
3138 OS/9000 i[34]86-*-os9k
3139 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3142 * Hitachi SH7000 and E7000-PC ICE support
3144 There is now support for communicating with the Hitachi E7000-PC ICE.
3145 This is available automatically when GDB is configured for the SH.
3149 As usual, a variety of small fixes and improvements, both generic
3150 and configuration-specific. See the ChangeLog for more detail.
3152 *** Changes in GDB-4.12:
3154 * Irix 5 is now supported
3158 GDB-4.12 on the HPPA has a number of changes which make it unable
3159 to debug the output from the currently released versions of GCC and
3160 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3161 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3162 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3165 *** Changes in GDB-4.11:
3167 * User visible changes:
3171 The "set remotedebug" option is now consistent between the mips remote
3172 target, remote targets using the gdb-specific protocol, UDI (AMD's
3173 debug protocol for the 29k) and the 88k bug monitor. It is now an
3174 integer specifying a debug level (normally 0 or 1, but 2 means more
3175 debugging info for the mips target).
3177 * DEC Alpha native support
3179 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3180 debug info, but GDB works fairly well with the DEC compiler and should
3181 work with a future GCC release. See the README file for a few
3182 Alpha-specific notes.
3184 * Preliminary thread implementation
3186 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3188 * LynxOS native and target support for 386
3190 This release has been hosted on LynxOS 2.2, and also can be configured
3191 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3194 * Improvements in C++ mangling/demangling.
3196 This release has much better g++ debugging, specifically in name
3197 mangling/demangling, virtual function calls, print virtual table,
3198 call methods, ...etc.
3200 *** Changes in GDB-4.10:
3202 * User visible changes:
3204 Remote debugging using the GDB-specific (`target remote') protocol now
3205 supports the `load' command. This is only useful if you have some
3206 other way of getting the stub to the target system, and you can put it
3207 somewhere in memory where it won't get clobbered by the download.
3209 Filename completion now works.
3211 When run under emacs mode, the "info line" command now causes the
3212 arrow to point to the line specified. Also, "info line" prints
3213 addresses in symbolic form (as well as hex).
3215 All vxworks based targets now support a user settable option, called
3216 vxworks-timeout. This option represents the number of seconds gdb
3217 should wait for responses to rpc's. You might want to use this if
3218 your vxworks target is, perhaps, a slow software simulator or happens
3219 to be on the far side of a thin network line.
3223 This release contains support for using a DEC alpha as a GDB host for
3224 cross debugging. Native alpha debugging is not supported yet.
3227 *** Changes in GDB-4.9:
3231 This is the first GDB release which is accompanied by a matching testsuite.
3232 The testsuite requires installation of dejagnu, which should be available
3233 via ftp from most sites that carry GNU software.
3237 'Cfront' style demangling has had its name changed to 'ARM' style, to
3238 emphasize that it was written from the specifications in the C++ Annotated
3239 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3240 disclaimers, it still generated too much confusion with users attempting to
3241 use gdb with AT&T cfront.
3245 GDB now uses a standard remote interface to a simulator library.
3246 So far, the library contains simulators for the Zilog Z8001/2, the
3247 Hitachi H8/300, H8/500 and Super-H.
3249 * New targets supported
3251 H8/300 simulator h8300-hitachi-hms or h8300hms
3252 H8/500 simulator h8500-hitachi-hms or h8500hms
3253 SH simulator sh-hitachi-hms or sh
3254 Z8000 simulator z8k-zilog-none or z8ksim
3255 IDT MIPS board over serial line mips-idt-ecoff
3257 Cross-debugging to GO32 targets is supported. It requires a custom
3258 version of the i386-stub.c module which is integrated with the
3259 GO32 memory extender.
3261 * New remote protocols
3263 MIPS remote debugging protocol.
3265 * New source languages supported
3267 This version includes preliminary support for Chill, a Pascal like language
3268 used by telecommunications companies. Chill support is also being integrated
3269 into the GNU compiler, but we don't know when it will be publically available.
3272 *** Changes in GDB-4.8:
3274 * HP Precision Architecture supported
3276 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3277 version of this support was available as a set of patches from the
3278 University of Utah. GDB does not support debugging of programs
3279 compiled with the HP compiler, because HP will not document their file
3280 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3281 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3283 Many problems in the preliminary version have been fixed.
3285 * Faster and better demangling
3287 We have improved template demangling and fixed numerous bugs in the GNU style
3288 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3289 character types (wchar_t) are now supported. Demangling of each symbol is now
3290 only done once, and is cached when the symbol table for a file is read in.
3291 This results in a small increase in memory usage for C programs, a moderate
3292 increase in memory usage for C++ programs, and a fantastic speedup in
3295 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3296 from the specifications in the Annotated Reference Manual, which AT&T's
3297 compiler does not actually implement.
3299 * G++ multiple inheritance compiler problem
3301 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3302 inheritance lattices was reworked to properly discover ambiguities. We
3303 recently found an example which causes this new algorithm to fail in a
3304 very subtle way, producing bad debug information for those classes.
3305 The file 'gcc.patch' (in this directory) can be applied to gcc to
3306 circumvent the problem. A future GCC release will contain a complete
3309 The previous G++ debug info problem (mentioned below for the gdb-4.7
3310 release) is fixed in gcc version 2.3.2.
3312 * Improved configure script
3314 The `configure' script will now attempt to guess your system type if
3315 you don't supply a host system type. The old scheme of supplying a
3316 host system triplet is preferable over using this. All the magic is
3317 done in the new `config.guess' script. Examine it for details.
3319 We have also brought our configure script much more in line with the FSF's
3320 version. It now supports the --with-xxx options. In particular,
3321 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3322 The resulting GDB will not be able to read arbitrary object file formats --
3323 only the format ``expected'' to be used on the configured target system.
3324 We hope to make this the default in a future release.
3326 * Documentation improvements
3328 There's new internal documentation on how to modify GDB, and how to
3329 produce clean changes to the code. We implore people to read it
3330 before submitting changes.
3332 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3333 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3334 `info' files are also provided. To build `info' files from scratch,
3335 you will need the latest `makeinfo' release, which will be available in
3336 a future texinfo-X.Y release.
3338 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3339 We're not sure exactly which versions have this problem, but it has
3340 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3341 or better. If that isn't possible, there is a patch in
3342 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3343 around this problem.
3347 GDB now supports array constants that can be used in expressions typed in by
3348 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3349 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3352 The new directory `gdb/sparclite' contains a program that demonstrates
3353 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3355 * New native hosts supported
3357 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3358 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3360 * New targets supported
3362 AMD 29k family via UDI a29k-amd-udi or udi29k
3364 * New file formats supported
3366 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3367 HPUX core files, and SCO 3.2v2 core files.
3371 Attaching to processes now works again; thanks for the many bug reports.
3373 We have also stomped on a bunch of core dumps caused by
3374 printf_filtered("%s") problems.
3376 We eliminated a copyright problem on the rpc and ptrace header files
3377 for VxWorks, which was discovered at the last minute during the 4.7
3378 release. You should now be able to build a VxWorks GDB.
3380 You can now interrupt gdb while an attached process is running. This
3381 will cause the attached process to stop, and give control back to GDB.
3383 We fixed problems caused by using too many file descriptors
3384 for reading symbols from object files and libraries. This was
3385 especially a problem for programs that used many (~100) shared
3388 The `step' command now only enters a subroutine if there is line number
3389 information for the subroutine. Otherwise it acts like the `next'
3390 command. Previously, `step' would enter subroutines if there was
3391 any debugging information about the routine. This avoids problems
3392 when using `cc -g1' on MIPS machines.
3394 * Internal improvements
3396 GDB's internal interfaces have been improved to make it easier to support
3397 debugging of multiple languages in the future.
3399 GDB now uses a common structure for symbol information internally.
3400 Minimal symbols (derived from linkage symbols in object files), partial
3401 symbols (from a quick scan of debug information), and full symbols
3402 contain a common subset of information, making it easier to write
3403 shared code that handles any of them.
3405 * New command line options
3407 We now accept --silent as an alias for --quiet.
3411 The memory-mapped-malloc library is now licensed under the GNU Library
3412 General Public License.
3414 *** Changes in GDB-4.7:
3416 * Host/native/target split
3418 GDB has had some major internal surgery to untangle the support for
3419 hosts and remote targets. Now, when you configure GDB for a remote
3420 target, it will no longer load in all of the support for debugging
3421 local programs on the host. When fully completed and tested, this will
3422 ensure that arbitrary host/target combinations are possible.
3424 The primary conceptual shift is to separate the non-portable code in
3425 GDB into three categories. Host specific code is required any time GDB
3426 is compiled on that host, regardless of the target. Target specific
3427 code relates to the peculiarities of the target, but can be compiled on
3428 any host. Native specific code is everything else: it can only be
3429 built when the host and target are the same system. Child process
3430 handling and core file support are two common `native' examples.
3432 GDB's use of /proc for controlling Unix child processes is now cleaner.
3433 It has been split out into a single module under the `target_ops' vector,
3434 plus two native-dependent functions for each system that uses /proc.
3436 * New hosts supported
3438 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3439 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3440 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3442 * New targets supported
3444 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3445 68030 and CPU32 m68030-*-*, m68332-*-*
3447 * New native hosts supported
3449 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3450 (386bsd is not well tested yet)
3451 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3453 * New file formats supported
3455 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3456 supports reading of `a.out.adobe' object files, which are an a.out
3457 format extended with minimal information about multiple sections.
3461 `show copying' is the same as the old `info copying'.
3462 `show warranty' is the same as `info warrantee'.
3463 These were renamed for consistency. The old commands continue to work.
3465 `info handle' is a new alias for `info signals'.
3467 You can now define pre-command hooks, which attach arbitrary command
3468 scripts to any command. The commands in the hook will be executed
3469 prior to the user's command. You can also create a hook which will be
3470 executed whenever the program stops. See gdb.texinfo.
3474 We now deal with Cfront style name mangling, and can even extract type
3475 info from mangled symbols. GDB can automatically figure out which
3476 symbol mangling style your C++ compiler uses.
3478 Calling of methods and virtual functions has been improved as well.
3482 The crash that occured when debugging Sun Ansi-C compiled binaries is
3483 fixed. This was due to mishandling of the extra N_SO stabs output
3486 We also finally got Ultrix 4.2 running in house, and fixed core file
3487 support, with help from a dozen people on the net.
3489 John M. Farrell discovered that the reason that single-stepping was so
3490 slow on all of the Mips based platforms (primarily SGI and DEC) was
3491 that we were trying to demangle and lookup a symbol used for internal
3492 purposes on every instruction that was being stepped through. Changing
3493 the name of that symbol so that it couldn't be mistaken for a C++
3494 mangled symbol sped things up a great deal.
3496 Rich Pixley sped up symbol lookups in general by getting much smarter
3497 about when C++ symbol mangling is necessary. This should make symbol
3498 completion (TAB on the command line) much faster. It's not as fast as
3499 we'd like, but it's significantly faster than gdb-4.6.
3503 A new user controllable variable 'call_scratch_address' can
3504 specify the location of a scratch area to be used when GDB
3505 calls a function in the target. This is necessary because the
3506 usual method of putting the scratch area on the stack does not work
3507 in systems that have separate instruction and data spaces.
3509 We integrated changes to support the 29k UDI (Universal Debugger
3510 Interface), but discovered at the last minute that we didn't have all
3511 of the appropriate copyright paperwork. We are working with AMD to
3512 resolve this, and hope to have it available soon.
3516 We have sped up the remote serial line protocol, especially for targets
3517 with lots of registers. It now supports a new `expedited status' ('T')
3518 message which can be used in place of the existing 'S' status message.
3519 This allows the remote stub to send only the registers that GDB
3520 needs to make a quick decision about single-stepping or conditional
3521 breakpoints, eliminating the need to fetch the entire register set for
3522 each instruction being stepped through.
3524 The GDB remote serial protocol now implements a write-through cache for
3525 registers, only re-reading the registers if the target has run.
3527 There is also a new remote serial stub for SPARC processors. You can
3528 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3529 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3530 processor with a serial port.
3534 Configure.in files have become much easier to read and modify. A new
3535 `table driven' format makes it more obvious what configurations are
3536 supported, and what files each one uses.
3540 There is a new opcodes library which will eventually contain all of the
3541 disassembly routines and opcode tables. At present, it only contains
3542 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3543 disassembler (binutils/objdump) to share these routines.
3545 The libiberty library is now copylefted under the GNU Library General
3546 Public License. This allows more liberal use, and was done so libg++
3547 can use it. This makes no difference to GDB, since the Library License
3548 grants all the rights from the General Public License.
3552 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3553 reference to the stabs symbol info used by the debugger. It is (as far
3554 as we know) the only published document on this fascinating topic. We
3555 encourage you to read it, compare it to the stabs information on your
3556 system, and send improvements on the document in general (to
3557 bug-gdb@prep.ai.mit.edu).
3559 And, of course, many bugs have been fixed.
3562 *** Changes in GDB-4.6:
3564 * Better support for C++ function names
3566 GDB now accepts as input the "demangled form" of C++ overloaded function
3567 names and member function names, and can do command completion on such names
3568 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3569 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3570 Make use of command completion, it is your friend.
3572 GDB also now accepts a variety of C++ mangled symbol formats. They are
3573 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3574 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3575 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3576 for the list of formats.
3578 * G++ symbol mangling problem
3580 Recent versions of gcc have a bug in how they emit debugging information for
3581 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3582 directory) can be applied to gcc to fix the problem. Alternatively, if you
3583 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3584 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3585 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3588 * New 'maintenance' command
3590 All of the commands related to hacking GDB internals have been moved out of
3591 the main command set, and now live behind the 'maintenance' command. This
3592 can also be abbreviated as 'mt'. The following changes were made:
3594 dump-me -> maintenance dump-me
3595 info all-breakpoints -> maintenance info breakpoints
3596 printmsyms -> maintenance print msyms
3597 printobjfiles -> maintenance print objfiles
3598 printpsyms -> maintenance print psymbols
3599 printsyms -> maintenance print symbols
3601 The following commands are new:
3603 maintenance demangle Call internal GDB demangler routine to
3604 demangle a C++ link name and prints the result.
3605 maintenance print type Print a type chain for a given symbol
3607 * Change to .gdbinit file processing
3609 We now read the $HOME/.gdbinit file before processing the argv arguments
3610 (e.g. reading symbol files or core files). This allows global parameters to
3611 be set, which will apply during the symbol reading. The ./.gdbinit is still
3612 read after argv processing.
3614 * New hosts supported
3616 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3618 GNU/Linux support i386-unknown-linux or linux
3620 We are also including code to support the HP/PA running BSD and HPUX. This
3621 is almost guaranteed not to work, as we didn't have time to test or build it
3622 for this release. We are including it so that the more adventurous (or
3623 masochistic) of you can play with it. We also had major problems with the
3624 fact that the compiler that we got from HP doesn't support the -g option.
3627 * New targets supported
3629 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3631 * More smarts about finding #include files
3633 GDB now remembers the compilation directory for all include files, and for
3634 all files from which C is generated (like yacc and lex sources). This
3635 greatly improves GDB's ability to find yacc/lex sources, and include files,
3636 especially if you are debugging your program from a directory different from
3637 the one that contains your sources.
3639 We also fixed a bug which caused difficulty with listing and setting
3640 breakpoints in include files which contain C code. (In the past, you had to
3641 try twice in order to list an include file that you hadn't looked at before.)
3643 * Interesting infernals change
3645 GDB now deals with arbitrary numbers of sections, where the symbols for each
3646 section must be relocated relative to that section's landing place in the
3647 target's address space. This work was needed to support ELF with embedded
3648 stabs used by Solaris-2.0.
3650 * Bug fixes (of course!)
3652 There have been loads of fixes for the following things:
3653 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3654 i960, stabs, DOS(GO32), procfs, etc...
3656 See the ChangeLog for details.
3658 *** Changes in GDB-4.5:
3660 * New machines supported (host and target)
3662 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3664 SGI Irix-4.x mips-sgi-irix4 or iris4
3666 * New malloc package
3668 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3669 Mmalloc is capable of handling mutiple heaps of memory. It is also
3670 capable of saving a heap to a file, and then mapping it back in later.
3671 This can be used to greatly speedup the startup of GDB by using a
3672 pre-parsed symbol table which lives in a mmalloc managed heap. For
3673 more details, please read mmalloc/mmalloc.texi.
3677 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3678 'help info proc' for details.
3680 * MIPS ecoff symbol table format
3682 The code that reads MIPS symbol table format is now supported on all hosts.
3683 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3686 * File name changes for MS-DOS
3688 Many files in the config directories have been renamed to make it easier to
3689 support GDB on MS-DOSe systems (which have very restrictive file name
3690 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3691 environment) is close to working but has some remaining problems. Note
3692 that debugging of DOS programs is not supported, due to limitations
3693 in the ``operating system'', but it can be used to host cross-debugging.
3695 * Cross byte order fixes
3697 Many fixes have been made to support cross debugging of Sparc and MIPS
3698 targets from hosts whose byte order differs.
3700 * New -mapped and -readnow options
3702 If memory-mapped files are available on your system through the 'mmap'
3703 system call, you can use the -mapped option on the `file' or
3704 `symbol-file' commands to cause GDB to write the symbols from your
3705 program into a reusable file. If the program you are debugging is
3706 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3707 Future GDB debugging sessions will notice the presence of this file,
3708 and will quickly map in symbol information from it, rather than reading
3709 the symbol table from the executable program. Using the '-mapped'
3710 option in a GDB `file' or `symbol-file' command has the same effect as
3711 starting GDB with the '-mapped' command-line option.
3713 You can cause GDB to read the entire symbol table immediately by using
3714 the '-readnow' option with any of the commands that load symbol table
3715 information (or on the GDB command line). This makes the command
3716 slower, but makes future operations faster.
3718 The -mapped and -readnow options are typically combined in order to
3719 build a `fred.syms' file that contains complete symbol information.
3720 A simple GDB invocation to do nothing but build a `.syms' file for future
3723 gdb -batch -nx -mapped -readnow programname
3725 The `.syms' file is specific to the host machine on which GDB is run.
3726 It holds an exact image of GDB's internal symbol table. It cannot be
3727 shared across multiple host platforms.
3729 * longjmp() handling
3731 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3732 siglongjmp() without losing control. This feature has not yet been ported to
3733 all systems. It currently works on many 386 platforms, all MIPS-based
3734 platforms (SGI, DECstation, etc), and Sun3/4.
3738 Preliminary work has been put in to support the new Solaris OS from Sun. At
3739 this time, it can control and debug processes, but it is not capable of
3744 As always, many many bug fixes. The major areas were with g++, and mipsread.
3745 People using the MIPS-based platforms should experience fewer mysterious
3746 crashes and trashed symbol tables.
3748 *** Changes in GDB-4.4:
3750 * New machines supported (host and target)
3752 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3754 BSD Reno on Vax vax-dec-bsd
3755 Ultrix on Vax vax-dec-ultrix
3757 * New machines supported (target)
3759 AMD 29000 embedded, using EBMON a29k-none-none
3763 GDB continues to improve its handling of C++. `References' work better.
3764 The demangler has also been improved, and now deals with symbols mangled as
3765 per the Annotated C++ Reference Guide.
3767 GDB also now handles `stabs' symbol information embedded in MIPS
3768 `ecoff' symbol tables. Since the ecoff format was not easily
3769 extensible to handle new languages such as C++, this appeared to be a
3770 good way to put C++ debugging info into MIPS binaries. This option
3771 will be supported in the GNU C compiler, version 2, when it is
3774 * New features for SVR4
3776 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3777 shared libraries. Debugging dynamically linked programs should present
3778 only minor differences from debugging statically linked programs.
3780 The `info proc' command will print out information about any process
3781 on an SVR4 system (including the one you are debugging). At the moment,
3782 it prints the address mappings of the process.
3784 If you bring up GDB on another SVR4 system, please send mail to
3785 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3787 * Better dynamic linking support in SunOS
3789 Reading symbols from shared libraries which contain debugging symbols
3790 now works properly. However, there remain issues such as automatic
3791 skipping of `transfer vector' code during function calls, which
3792 make it harder to debug code in a shared library, than to debug the
3793 same code linked statically.
3797 GDB is now using the latest `getopt' routines from the FSF. This
3798 version accepts the -- prefix for options with long names. GDB will
3799 continue to accept the old forms (-option and +option) as well.
3800 Various single letter abbreviations for options have been explicity
3801 added to the option table so that they won't get overshadowed in the
3802 future by other options that begin with the same letter.
3806 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3807 Many assorted bugs have been handled. Many more remain to be handled.
3808 See the various ChangeLog files (primarily in gdb and bfd) for details.
3811 *** Changes in GDB-4.3:
3813 * New machines supported (host and target)
3815 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3816 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3817 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3819 * Almost SCO Unix support
3821 We had hoped to support:
3822 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3823 (except for core file support), but we discovered very late in the release
3824 that it has problems with process groups that render gdb unusable. Sorry
3825 about that. I encourage people to fix it and post the fixes.
3827 * Preliminary ELF and DWARF support
3829 GDB can read ELF object files on System V Release 4, and can handle
3830 debugging records for C, in DWARF format, in ELF files. This support
3831 is preliminary. If you bring up GDB on another SVR4 system, please
3832 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3837 GDB now uses the latest `readline' library. One user-visible change
3838 is that two tabs will list possible command completions, which previously
3839 required typing M-? (meta-question mark, or ESC ?).
3843 The `stepi' bug that many of you noticed has been squashed.
3844 Many bugs in C++ have been handled. Many more remain to be handled.
3845 See the various ChangeLog files (primarily in gdb and bfd) for details.
3847 * State of the MIPS world (in case you wondered):
3849 GDB can understand the symbol tables emitted by the compilers
3850 supplied by most vendors of MIPS-based machines, including DEC. These
3851 symbol tables are in a format that essentially nobody else uses.
3853 Some versions of gcc come with an assembler post-processor called
3854 mips-tfile. This program is required if you want to do source-level
3855 debugging of gcc-compiled programs. I believe FSF does not ship
3856 mips-tfile with gcc version 1, but it will eventually come with gcc
3859 Debugging of g++ output remains a problem. g++ version 1.xx does not
3860 really support it at all. (If you're lucky, you should be able to get
3861 line numbers and stack traces to work, but no parameters or local
3862 variables.) With some work it should be possible to improve the
3865 When gcc version 2 is released, you will have somewhat better luck.
3866 However, even then you will get confusing results for inheritance and
3869 We will eventually provide full debugging of g++ output on
3870 DECstations. This will probably involve some kind of stabs-in-ecoff
3871 encapulation, but the details have not been worked out yet.
3874 *** Changes in GDB-4.2:
3876 * Improved configuration
3878 Only one copy of `configure' exists now, and it is not self-modifying.
3879 Porting BFD is simpler.
3883 The `step' and `next' commands now only stop at the first instruction
3884 of a source line. This prevents the multiple stops that used to occur
3885 in switch statements, for-loops, etc. `Step' continues to stop if a
3886 function that has debugging information is called within the line.
3890 Lots of small bugs fixed. More remain.
3892 * New host supported (not target)
3894 Intel 386 PC clone running Mach i386-none-mach
3897 *** Changes in GDB-4.1:
3899 * Multiple source language support
3901 GDB now has internal scaffolding to handle several source languages.
3902 It determines the type of each source file from its filename extension,
3903 and will switch expression parsing and number formatting to match the
3904 language of the function in the currently selected stack frame.
3905 You can also specifically set the language to be used, with
3906 `set language c' or `set language modula-2'.
3910 GDB now has preliminary support for the GNU Modula-2 compiler,
3911 currently under development at the State University of New York at
3912 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3913 continue through the fall of 1991 and into 1992.
3915 Other Modula-2 compilers are currently not supported, and attempting to
3916 debug programs compiled with them will likely result in an error as the
3917 symbol table is read. Feel free to work on it, though!
3919 There are hooks in GDB for strict type checking and range checking,
3920 in the `Modula-2 philosophy', but they do not currently work.
3924 GDB can now write to executable and core files (e.g. patch
3925 a variable's value). You must turn this switch on, specify
3926 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3927 by assigning a new value to a variable. Modifications take
3930 * Automatic SunOS shared library reading
3932 When you run your program, GDB automatically determines where its
3933 shared libraries (if any) have been loaded, and reads their symbols.
3934 The `share' command is no longer needed. This also works when
3935 examining core files.
3939 You can specify the number of lines that the `list' command shows.
3942 * New machines supported (host and target)
3944 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3945 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3946 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3948 * New hosts supported (not targets)
3950 IBM RT/PC: romp-ibm-aix or rtpc
3952 * New targets supported (not hosts)
3954 AMD 29000 embedded with COFF a29k-none-coff
3955 AMD 29000 embedded with a.out a29k-none-aout
3956 Ultracomputer remote kernel debug a29k-nyu-kern
3958 * New remote interfaces
3964 *** Changes in GDB-4.0:
3968 Wide output is wrapped at good places to make the output more readable.
3970 Gdb now supports cross-debugging from a host machine of one type to a
3971 target machine of another type. Communication with the target system
3972 is over serial lines. The ``target'' command handles connecting to the
3973 remote system; the ``load'' command will download a program into the
3974 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3975 also supports debugging of realtime processes running under VxWorks,
3976 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3977 stub on the target system.
3979 New CPUs supported include the AMD 29000 and Intel 960.
3981 GDB now reads object files and symbol tables via a ``binary file''
3982 library, which allows a single copy of GDB to debug programs of multiple
3983 object file types such as a.out and coff.
3985 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3986 refcard.dvi and refcard.ps are available to format it).
3989 * Control-Variable user interface simplified
3991 All variables that control the operation of the debugger can be set
3992 by the ``set'' command, and displayed by the ``show'' command.
3994 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3995 ``Show prompt'' produces the response:
3996 Gdb's prompt is new-gdb=>.
3998 What follows are the NEW set commands. The command ``help set'' will
3999 print a complete list of old and new set commands. ``help set FOO''
4000 will give a longer description of the variable FOO. ``show'' will show
4001 all of the variable descriptions and their current settings.
4003 confirm on/off: Enables warning questions for operations that are
4004 hard to recover from, e.g. rerunning the program while
4005 it is already running. Default is ON.
4007 editing on/off: Enables EMACS style command line editing
4008 of input. Previous lines can be recalled with
4009 control-P, the current line can be edited with control-B,
4010 you can search for commands with control-R, etc.
4013 history filename NAME: NAME is where the gdb command history
4014 will be stored. The default is .gdb_history,
4015 or the value of the environment variable
4018 history size N: The size, in commands, of the command history. The
4019 default is 256, or the value of the environment variable
4022 history save on/off: If this value is set to ON, the history file will
4023 be saved after exiting gdb. If set to OFF, the
4024 file will not be saved. The default is OFF.
4026 history expansion on/off: If this value is set to ON, then csh-like
4027 history expansion will be performed on
4028 command line input. The default is OFF.
4030 radix N: Sets the default radix for input and output. It can be set
4031 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4032 in the current radix, so "set radix 10" is always a no-op.
4034 height N: This integer value is the number of lines on a page. Default
4035 is 24, the current `stty rows'' setting, or the ``li#''
4036 setting from the termcap entry matching the environment
4039 width N: This integer value is the number of characters on a line.
4040 Default is 80, the current `stty cols'' setting, or the ``co#''
4041 setting from the termcap entry matching the environment
4044 Note: ``set screensize'' is obsolete. Use ``set height'' and
4045 ``set width'' instead.
4047 print address on/off: Print memory addresses in various command displays,
4048 such as stack traces and structure values. Gdb looks
4049 more ``symbolic'' if you turn this off; it looks more
4050 ``machine level'' with it on. Default is ON.
4052 print array on/off: Prettyprint arrays. New convenient format! Default
4055 print demangle on/off: Print C++ symbols in "source" form if on,
4058 print asm-demangle on/off: Same, for assembler level printouts
4061 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4064 * Support for Epoch Environment.
4066 The epoch environment is a version of Emacs v18 with windowing. One
4067 new command, ``inspect'', is identical to ``print'', except that if you
4068 are running in the epoch environment, the value is printed in its own
4072 * Support for Shared Libraries
4074 GDB can now debug programs and core files that use SunOS shared libraries.
4075 Symbols from a shared library cannot be referenced
4076 before the shared library has been linked with the program (this
4077 happens after you type ``run'' and before the function main() is entered).
4078 At any time after this linking (including when examining core files
4079 from dynamically linked programs), gdb reads the symbols from each
4080 shared library when you type the ``sharedlibrary'' command.
4081 It can be abbreviated ``share''.
4083 sharedlibrary REGEXP: Load shared object library symbols for files
4084 matching a unix regular expression. No argument
4085 indicates to load symbols for all shared libraries.
4087 info sharedlibrary: Status of loaded shared libraries.
4092 A watchpoint stops execution of a program whenever the value of an
4093 expression changes. Checking for this slows down execution
4094 tremendously whenever you are in the scope of the expression, but is
4095 quite useful for catching tough ``bit-spreader'' or pointer misuse
4096 problems. Some machines such as the 386 have hardware for doing this
4097 more quickly, and future versions of gdb will use this hardware.
4099 watch EXP: Set a watchpoint (breakpoint) for an expression.
4101 info watchpoints: Information about your watchpoints.
4103 delete N: Deletes watchpoint number N (same as breakpoints).
4104 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4105 enable N: Re-enables watchpoint number N (same as breakpoints).
4108 * C++ multiple inheritance
4110 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4113 * C++ exception handling
4115 Gdb now supports limited C++ exception handling. Besides the existing
4116 ability to breakpoint on an exception handler, gdb can breakpoint on
4117 the raising of an exception (before the stack is peeled back to the
4120 catch FOO: If there is a FOO exception handler in the dynamic scope,
4121 set a breakpoint to catch exceptions which may be raised there.
4122 Multiple exceptions (``catch foo bar baz'') may be caught.
4124 info catch: Lists all exceptions which may be caught in the
4125 current stack frame.
4128 * Minor command changes
4130 The command ``call func (arg, arg, ...)'' now acts like the print
4131 command, except it does not print or save a value if the function's result
4132 is void. This is similar to dbx usage.
4134 The ``up'' and ``down'' commands now always print the frame they end up
4135 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4136 frames without printing.
4138 * New directory command
4140 'dir' now adds directories to the FRONT of the source search path.
4141 The path starts off empty. Source files that contain debug information
4142 about the directory in which they were compiled can be found even
4143 with an empty path; Sun CC and GCC include this information. If GDB can't
4144 find your source file in the current directory, type "dir .".
4146 * Configuring GDB for compilation
4148 For normal use, type ``./configure host''. See README or gdb.texinfo
4151 GDB now handles cross debugging. If you are remotely debugging between
4152 two different machines, type ``./configure host -target=targ''.
4153 Host is the machine where GDB will run; targ is the machine
4154 where the program that you are debugging will run.