1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.0
8 Xilinx MicroBlaze microblaze-*-*
13 Xilinx MicroBlaze microblaze
16 * Multi-program debugging.
18 GDB now has support for multi-program (a.k.a. multi-executable or
19 multi-exec) debugging. This allows for debugging multiple inferiors
20 simultaneously each running a different program under the same GDB
21 session. See "Debugging Multiple Inferiors and Programs" in the
22 manual for more information. This implied some user visible changes
23 in the multi-inferior support. For example, "info inferiors" now
24 lists inferiors that are not running yet or that have exited
25 already. See also "New commands" and "New options" below.
27 * New tracing features
29 GDB's tracepoint facility now includes several new features:
31 ** Trace state variables
33 GDB tracepoints now include support for trace state variables, which
34 are variables managed by the target agent during a tracing
35 experiment. They are useful for tracepoints that trigger each
36 other, so for instance one tracepoint can count hits in a variable,
37 and then a second tracepoint has a condition that is true when the
38 count reaches a particular value. Trace state variables share the
39 $-syntax of GDB convenience variables, and can appear in both
40 tracepoint actions and condition expressions. Use the "tvariable"
41 command to create, and "info tvariables" to view; see "Trace State
42 Variables" in the manual for more detail.
46 GDB now includes an option for defining fast tracepoints, which
47 targets may implement more efficiently, such as by installing a jump
48 into the target agent rather than a trap instruction. The resulting
49 speedup can be by two orders of magnitude or more, although the
50 tradeoff is that some program locations on some target architectures
51 might not allow fast tracepoint installation, for instance if the
52 instruction to be replaced is shorter than the jump. To request a
53 fast tracepoint, use the "ftrace" command, with syntax identical to
54 the regular trace command.
56 ** Disconnected tracing
58 It is now possible to detach GDB from the target while it is running
59 a trace experiment, then reconnect later to see how the experiment
60 is going. In addition, a new variable disconnected-tracing lets you
61 tell the target agent whether to continue running a trace if the
62 connection is lost unexpectedly.
67 The disassemble command, when invoked with two arguments, now requires
68 the arguments to be comma-separated.
71 The info variables command now displays variable definitions. Files
72 which only declare a variable are not shown.
74 * New commands (for set/show, see "New options" below)
76 record save [<FILENAME>]
77 Save a file (in core file format) containing the process record
78 execution log for replay debugging at a later time.
80 record restore <FILENAME>
81 Restore the process record execution log that was saved at an
82 earlier time, for replay debugging.
84 add-inferior [-copies <N>] [-exec <FILENAME>]
87 clone-inferior [-copies <N>] [ID]
88 Make a new inferior ready to execute the same program another
94 maint info program-spaces
95 List the program spaces loaded into GDB.
97 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
98 show remote interrupt-sequence
99 Allow the user to select one of ^C, a BREAK signal or BREAK-g
100 as the sequence to the remote target in order to interrupt the execution.
101 Ctrl-C is a default. Some system prefers BREAK which is high level of
102 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
103 Magic SysRq g. It is BREAK signal and character 'g'.
105 set remote interrupt-on-connect [on | off]
106 show remote interrupt-on-connect
107 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
108 remote target when gdb connects to it. This is needed when you debug
111 set remotebreak [on | off]
113 Deprecated. Use "set/show remote interrupt-sequence" instead.
115 tvariable $NAME [ = EXP ]
116 Create or modify a trace state variable.
119 List trace state variables and their values.
121 delete tvariable $NAME ...
122 Delete one or more trace state variables.
125 Evaluate the given expressions without collecting anything into the
126 trace buffer. (Valid in tracepoint actions only.)
128 ftrace FN / FILE:LINE / *ADDR
129 Define a fast tracepoint at the given function, line, or address.
131 * New expression syntax
133 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
134 GDB now parses 0b101010 identically with 42.
138 set follow-exec-mode new|same
139 show follow-exec-mode
140 Control whether GDB reuses the same inferior across an exec call or
141 creates a new one. This is useful to be able to restart the old
142 executable after the inferior having done an exec call.
144 set default-collect EXPR, ...
146 Define a list of expressions to be collected at each tracepoint.
147 This is a useful way to ensure essential items are not overlooked,
148 such as registers or a critical global variable.
150 set disconnected-tracing
151 show disconnected-tracing
152 If set to 1, the target is instructed to continue tracing if it
153 loses its connection to GDB. If 0, the target is to stop tracing
159 Define a trace state variable.
162 Get the current value of a trace state variable.
165 Set desired tracing behavior upon disconnection.
168 Get data about the tracepoints currently in use.
172 Process record now works correctly with hardware watchpoints.
174 Multiple bug fixes have been made to the mips-irix port, making it
175 much more reliable. In particular:
176 - Debugging threaded applications is now possible again. Previously,
177 GDB would hang while starting the program, or while waiting for
178 the program to stop at a breakpoint.
179 - Attaching to a running process no longer hangs.
180 - An error occurring while loading a core file has been fixed.
181 - Changing the value of the PC register now works again. This fixes
182 problems observed when using the "jump" command, or when calling
183 a function from GDB, or even when assigning a new value to $pc.
184 - With the "finish" and "return" commands, the return value for functions
185 returning a small array is now correctly printed.
186 - It is now possible to break on shared library code which gets executed
187 during a shared library init phase (code executed while executing
188 their .init section). Previously, the breakpoint would have no effect.
189 - GDB is now able to backtrace through the signal handler for
190 non-threaded programs.
192 PIE (Position Independent Executable) programs debugging is now supported.
193 This includes debugging execution of PIC (Position Independent Code) shared
194 libraries although for that, it should be possible to run such libraries as an
197 *** Changes in GDB 7.0
199 * GDB now has an interface for JIT compilation. Applications that
200 dynamically generate code can create symbol files in memory and register
201 them with GDB. For users, the feature should work transparently, and
202 for JIT developers, the interface is documented in the GDB manual in the
203 "JIT Compilation Interface" chapter.
205 * Tracepoints may now be conditional. The syntax is as for
206 breakpoints; either an "if" clause appended to the "trace" command,
207 or the "condition" command is available. GDB sends the condition to
208 the target for evaluation using the same bytecode format as is used
209 for tracepoint actions.
211 * "disassemble" command with a /r modifier, print the raw instructions
212 in hex as well as in symbolic form."
214 * Process record and replay
216 In a architecture environment that supports ``process record and
217 replay'', ``process record and replay'' target can record a log of
218 the process execution, and replay it with both forward and reverse
221 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
222 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
223 set execution-direction {forward|reverse}, for targets that support
226 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
227 feature is available with a native GDB running on kernel version
230 * GDB now has support for multi-byte and wide character sets on the
231 target. Strings whose character type is wchar_t, char16_t, or
232 char32_t are now correctly printed. GDB supports wide- and unicode-
233 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
234 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
235 `printf'. This feature requires iconv to work properly; if your
236 system does not have a working iconv, GDB can use GNU libiconv. See
237 the installation instructions for more information.
239 * GDB now supports automatic retrieval of shared library files from
240 remote targets. To use this feature, specify a system root that begins
241 with the `remote:' prefix, either via the `set sysroot' command or via
242 the `--with-sysroot' configure-time option.
244 * "info sharedlibrary" now takes an optional regex of libraries to show,
245 and it now reports if a shared library has no debugging information.
247 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
248 now complete on file names.
250 * When completing in expressions, gdb will attempt to limit
251 completions to allowable structure or union fields, where appropriate.
252 For instance, consider:
254 # struct example { int f1; double f2; };
255 # struct example variable;
258 If the user types TAB at the end of this command line, the available
259 completions will be "f1" and "f2".
261 * Inlined functions are now supported. They show up in backtraces, and
262 the "step", "next", and "finish" commands handle them automatically.
264 * GDB now supports the token-splicing (##) and stringification (#)
265 operators when expanding macros. It also supports variable-arity
268 * GDB now supports inspecting extra signal information, exported by
269 the new $_siginfo convenience variable. The feature is currently
270 implemented on linux ARM, i386 and amd64.
272 * GDB can now display the VFP floating point registers and NEON vector
273 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
274 can provide these registers (requires Linux 2.6.30 or later). Remote
275 and simulator targets may also provide them.
280 Search memory for a sequence of bytes.
283 Turn off `+'/`-' protocol acknowledgments to permit more efficient
284 operation over reliable transport links. Use of this packet is
285 controlled by the `set remote noack-packet' command.
288 Kill the process with the specified process ID. Use this in preference
289 to `k' when multiprocess protocol extensions are supported.
292 Obtains additional operating system information
296 Read or write additional signal information.
298 * Removed remote protocol undocumented extension
300 An undocumented extension to the remote protocol's `S' stop reply
301 packet that permited the stub to pass a process id was removed.
302 Remote servers should use the `T' stop reply packet instead.
304 * The "disassemble" command now supports an optional /m modifier to print mixed
307 * GDB now supports multiple function calling conventions according to the
308 DWARF-2 DW_AT_calling_convention function attribute.
310 * The SH target utilizes the aforementioned change to distinguish between gcc
311 and Renesas calling convention. It also adds the new CLI commands
312 `set/show sh calling-convention'.
314 * GDB can now read compressed debug sections, as produced by GNU gold
315 with the --compress-debug-sections=zlib flag.
317 * 64-bit core files are now supported on AIX.
319 * Thread switching is now supported on Tru64.
321 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
322 which will be allocated using malloc later in program execution.
324 * The qXfer:libraries:read remote procotol packet now allows passing a
325 list of section offsets.
327 * On GNU/Linux, GDB can now attach to stopped processes. Several race
328 conditions handling signals delivered during attach or thread creation
329 have also been fixed.
331 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
332 From the user's standpoint, all unqualified instances of True and False
333 are treated as the standard definitions, regardless of context.
335 * GDB now parses C++ symbol and type names more flexibly. For
338 template<typename T> class C { };
341 GDB will now correctly handle all of:
343 ptype C<char const *>
345 ptype C<const char *>
348 * New features in the GDB remote stub, gdbserver
350 - The "--wrapper" command-line argument tells gdbserver to use a
351 wrapper program to launch programs for debugging.
353 - On PowerPC and S/390 targets, it is now possible to use a single
354 gdbserver executable to debug both 32-bit and 64-bit programs.
355 (This requires gdbserver itself to be built as a 64-bit executable.)
357 - gdbserver uses the new noack protocol mode for TCP connections to
358 reduce communications latency, if also supported and enabled in GDB.
360 - Support for the sparc64-linux-gnu target is now included in
363 - The amd64-linux build of gdbserver now supports debugging both
364 32-bit and 64-bit programs.
366 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
367 now support hardware watchpoints, and will use them automatically
372 GDB now has support for scripting using Python. Whether this is
373 available is determined at configure time.
375 New GDB commands can now be written in Python.
377 * Ada tasking support
379 Ada tasks can now be inspected in GDB. The following commands have
383 Print the list of Ada tasks.
385 Print detailed information about task number N.
387 Print the task number of the current task.
389 Switch the context of debugging to task number N.
391 * Support for user-defined prefixed commands. The "define" command can
392 add new commands to existing prefixes, e.g. "target".
394 * Multi-inferior, multi-process debugging.
396 GDB now has generalized support for multi-inferior debugging. See
397 "Debugging Multiple Inferiors" in the manual for more information.
398 Although availability still depends on target support, the command
399 set is more uniform now. The GNU/Linux specific multi-forks support
400 has been migrated to this new framework. This implied some user
401 visible changes; see "New commands" and also "Removed commands"
404 * Target descriptions can now describe the target OS ABI. See the
405 "Target Description Format" section in the user manual for more
408 * Target descriptions can now describe "compatible" architectures
409 to indicate that the target can execute applications for a different
410 architecture in addition to those for the main target architecture.
411 See the "Target Description Format" section in the user manual for
414 * Multi-architecture debugging.
416 GDB now includes general supports for debugging applications on
417 hybrid systems that use more than one single processor architecture
418 at the same time. Each such hybrid architecture still requires
419 specific support to be added. The only hybrid architecture supported
420 in this version of GDB is the Cell Broadband Engine.
422 * GDB now supports integrated debugging of Cell/B.E. applications that
423 use both the PPU and SPU architectures. To enable support for hybrid
424 Cell/B.E. debugging, you need to configure GDB to support both the
425 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
426 --enable-targets configure option.
428 * Non-stop mode debugging.
430 For some targets, GDB now supports an optional mode of operation in
431 which you can examine stopped threads while other threads continue
432 to execute freely. This is referred to as non-stop mode, with the
433 old mode referred to as all-stop mode. See the "Non-Stop Mode"
434 section in the user manual for more information.
436 To be able to support remote non-stop debugging, a remote stub needs
437 to implement the non-stop mode remote protocol extensions, as
438 described in the "Remote Non-Stop" section of the user manual. The
439 GDB remote stub, gdbserver, has been adjusted to support these
440 extensions on linux targets.
442 * New commands (for set/show, see "New options" below)
444 catch syscall [NAME(S) | NUMBER(S)]
445 Catch system calls. Arguments, which should be names of system
446 calls or their numbers, mean catch only those syscalls. Without
447 arguments, every syscall will be caught. When the inferior issues
448 any of the specified syscalls, GDB will stop and announce the system
449 call, both when it is called and when its call returns. This
450 feature is currently available with a native GDB running on the
451 Linux Kernel, under the following architectures: x86, x86_64,
452 PowerPC and PowerPC64.
454 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
456 Search memory for a sequence of bytes.
458 maint set python print-stack
459 maint show python print-stack
460 Show a stack trace when an error is encountered in a Python script.
463 Invoke CODE by passing it to the Python interpreter.
468 These allow macros to be defined, undefined, and listed
472 Show operating system information about processes.
475 List the inferiors currently under GDB's control.
478 Switch focus to inferior number NUM.
481 Detach from inferior number NUM.
484 Kill inferior number NUM.
489 show spu stop-on-load
490 Control whether to stop for new SPE threads during Cell/B.E. debugging.
492 set spu auto-flush-cache
493 show spu auto-flush-cache
494 Control whether to automatically flush the software-managed cache
495 during Cell/B.E. debugging.
497 set sh calling-convention
498 show sh calling-convention
499 Control the calling convention used when calling SH target functions.
503 Control display of timestamps with GDB debugging output.
505 set disassemble-next-line
506 show disassemble-next-line
507 Control display of disassembled source lines or instructions when
510 set remote noack-packet
511 show remote noack-packet
512 Set/show the use of remote protocol QStartNoAckMode packet. See above
513 under "New remote packets."
515 set remote query-attached-packet
516 show remote query-attached-packet
517 Control use of remote protocol `qAttached' (query-attached) packet.
519 set remote read-siginfo-object
520 show remote read-siginfo-object
521 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
524 set remote write-siginfo-object
525 show remote write-siginfo-object
526 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
529 set remote reverse-continue
530 show remote reverse-continue
531 Control use of remote protocol 'bc' (reverse-continue) packet.
533 set remote reverse-step
534 show remote reverse-step
535 Control use of remote protocol 'bs' (reverse-step) packet.
537 set displaced-stepping
538 show displaced-stepping
539 Control displaced stepping mode. Displaced stepping is a way to
540 single-step over breakpoints without removing them from the debuggee.
541 Also known as "out-of-line single-stepping".
545 Control display of debugging info for displaced stepping.
547 maint set internal-error
548 maint show internal-error
549 Control what GDB does when an internal error is detected.
551 maint set internal-warning
552 maint show internal-warning
553 Control what GDB does when an internal warning is detected.
558 Use a wrapper program to launch programs for debugging.
560 set multiple-symbols (all|ask|cancel)
561 show multiple-symbols
562 The value of this variable can be changed to adjust the debugger behavior
563 when an expression or a breakpoint location contains an ambiguous symbol
564 name (an overloaded function name, for instance).
566 set breakpoint always-inserted
567 show breakpoint always-inserted
568 Keep breakpoints always inserted in the target, as opposed to inserting
569 them when resuming the target, and removing them when the target stops.
570 This option can improve debugger performance on slow remote targets.
572 set arm fallback-mode (arm|thumb|auto)
573 show arm fallback-mode
574 set arm force-mode (arm|thumb|auto)
576 These commands control how ARM GDB determines whether instructions
577 are ARM or Thumb. The default for both settings is auto, which uses
578 the current CPSR value for instructions without symbols; previous
579 versions of GDB behaved as if "set arm fallback-mode arm".
581 set disable-randomization
582 show disable-randomization
583 Standalone programs run with the virtual address space randomization enabled
584 by default on some platforms. This option keeps the addresses stable across
585 multiple debugging sessions.
589 Control whether other threads are stopped or not when some thread hits
594 Requests that asynchronous execution is enabled in the target, if available.
595 In this case, it's possible to resume target in the background, and interact
596 with GDB while the target is running. "show target-async" displays the
597 current state of asynchronous execution of the target.
599 set target-wide-charset
600 show target-wide-charset
601 The target-wide-charset is the name of the character set that GDB
602 uses when printing characters whose type is wchar_t.
604 set tcp auto-retry (on|off)
606 set tcp connect-timeout
607 show tcp connect-timeout
608 These commands allow GDB to retry failed TCP connections to a remote stub
609 with a specified timeout period; this is useful if the stub is launched
610 in parallel with GDB but may not be ready to accept connections immediately.
612 set libthread-db-search-path
613 show libthread-db-search-path
614 Control list of directories which GDB will search for appropriate
617 set schedule-multiple (on|off)
618 show schedule-multiple
619 Allow GDB to resume all threads of all processes or only threads of
624 Use more aggressive caching for accesses to the stack. This improves
625 performance of remote debugging (particularly backtraces) without
626 affecting correctness.
628 set interactive-mode (on|off|auto)
629 show interactive-mode
630 Control whether GDB runs in interactive mode (on) or not (off).
631 When in interactive mode, GDB waits for the user to answer all
632 queries. Otherwise, GDB does not wait and assumes the default
633 answer. When set to auto (the default), GDB determines which
634 mode to use based on the stdin settings.
639 For program forks, this is replaced by the new more generic `info
640 inferiors' command. To list checkpoints, you can still use the
641 `info checkpoints' command, which was an alias for the `info forks'
645 Replaced by the new `inferior' command. To switch between
646 checkpoints, you can still use the `restart' command, which was an
647 alias for the `fork' command.
650 This is removed, since some targets don't have a notion of
651 processes. To switch between processes, you can still use the
652 `inferior' command using GDB's own inferior number.
655 For program forks, this is replaced by the new more generic `kill
656 inferior' command. To delete a checkpoint, you can still use the
657 `delete checkpoint' command, which was an alias for the `delete
661 For program forks, this is replaced by the new more generic `detach
662 inferior' command. To detach a checkpoint, you can still use the
663 `detach checkpoint' command, which was an alias for the `detach
666 * New native configurations
668 x86/x86_64 Darwin i[34567]86-*-darwin*
670 x86_64 MinGW x86_64-*-mingw*
674 Lattice Mico32 lm32-*
675 x86 DICOS i[34567]86-*-dicos*
676 x86_64 DICOS x86_64-*-dicos*
679 * The GDB remote stub, gdbserver, now supports x86 Windows CE
680 (mingw32ce) debugging.
686 These commands were actually not implemented on any target.
688 *** Changes in GDB 6.8
690 * New native configurations
692 NetBSD/hppa hppa*-*netbsd*
693 Xtensa GNU/Linux xtensa*-*-linux*
697 NetBSD/hppa hppa*-*-netbsd*
698 Xtensa GNU/Lunux xtensa*-*-linux*
700 * Change in command line behavior -- corefiles vs. process ids.
702 When the '-p NUMBER' or '--pid NUMBER' options are used, and
703 attaching to process NUMBER fails, GDB no longer attempts to open a
704 core file named NUMBER. Attaching to a program using the -c option
705 is no longer supported. Instead, use the '-p' or '--pid' options.
707 * GDB can now be built as a native debugger for debugging Windows x86
708 (mingw32) Portable Executable (PE) programs.
710 * Pending breakpoints no longer change their number when their address
713 * GDB now supports breakpoints with multiple locations,
714 including breakpoints on C++ constructors, inside C++ templates,
715 and in inlined functions.
717 * GDB's ability to debug optimized code has been improved. GDB more
718 accurately identifies function bodies and lexical blocks that occupy
719 more than one contiguous range of addresses.
721 * Target descriptions can now describe registers for PowerPC.
723 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
724 registers on PowerPC targets.
726 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
727 targets even when the libthread_db library is not available.
729 * The GDB remote stub, gdbserver, now supports the new file transfer
730 commands (remote put, remote get, and remote delete).
732 * The GDB remote stub, gdbserver, now supports run and attach in
733 extended-remote mode.
735 * hppa*64*-*-hpux11* target broken
736 The debugger is unable to start a program and fails with the following
737 error: "Error trying to get information about dynamic linker".
738 The gdb-6.7 release is also affected.
740 * GDB now supports the --enable-targets= configure option to allow
741 building a single GDB executable that supports multiple remote
742 target architectures.
744 * GDB now supports debugging C and C++ programs which use the
745 Decimal Floating Point extension. In addition, the PowerPC target
746 now has a set of pseudo-registers to inspect decimal float values
747 stored in two consecutive float registers.
749 * The -break-insert MI command can optionally create pending
752 * Improved support for debugging Ada
753 Many improvements to the Ada language support have been made. These
755 - Better support for Ada2005 interface types
756 - Improved handling of arrays and slices in general
757 - Better support for Taft-amendment types
758 - The '{type} ADDRESS' expression is now allowed on the left hand-side
760 - Improved command completion in Ada
763 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
768 set print frame-arguments (all|scalars|none)
769 show print frame-arguments
770 The value of this variable can be changed to control which argument
771 values should be printed by the debugger when displaying a frame.
776 Transfer files to and from a remote target, and delete remote files.
783 Transfer files to and from a remote target, and delete remote files.
792 Open, close, read, write, and delete files on the remote system.
795 Attach to an existing process on the remote system, in extended-remote
799 Run a new process on the remote system, in extended-remote mode.
801 *** Changes in GDB 6.7
803 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
804 bfd, libiberty and opcodes, as revealed by static analysis donated by
805 Coverity, Inc. (http://scan.coverity.com).
807 * When looking up multiply-defined global symbols, GDB will now prefer the
808 symbol definition in the current shared library if it was built using the
809 -Bsymbolic linker option.
811 * When the Text User Interface (TUI) is not configured, GDB will now
812 recognize the -tui command-line option and print a message that the TUI
815 * The GDB remote stub, gdbserver, now has lower overhead for high
816 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
818 * GDB for MIPS targets now autodetects whether a remote target provides
819 32-bit or 64-bit register values.
821 * Support for C++ member pointers has been improved.
823 * GDB now understands XML target descriptions, which specify the
824 target's overall architecture. GDB can read a description from
825 a local file or over the remote serial protocol.
827 * Vectors of single-byte data use a new integer type which is not
828 automatically displayed as character or string data.
830 * The /s format now works with the print command. It displays
831 arrays of single-byte integers and pointers to single-byte integers
834 * Target descriptions can now describe target-specific registers,
835 for architectures which have implemented the support (currently
836 only ARM, M68K, and MIPS).
838 * GDB and the GDB remote stub, gdbserver, now support the XScale
841 * The GDB remote stub, gdbserver, has been updated to support
842 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
843 has been rewritten to use the standard GDB remote protocol.
845 * GDB can now step into C++ functions which are called through thunks.
847 * GDB for the Cell/B.E. SPU now supports overlay debugging.
849 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
850 layout. It also supports a TextSeg= and DataSeg= response when only
851 segment base addresses (rather than offsets) are available.
853 * The /i format now outputs any trailing branch delay slot instructions
854 immediately following the last instruction within the count specified.
856 * The GDB remote protocol "T" stop reply packet now supports a
857 "library" response. Combined with the new "qXfer:libraries:read"
858 packet, this response allows GDB to debug shared libraries on targets
859 where the operating system manages the list of loaded libraries (e.g.
860 Windows and SymbianOS).
862 * The GDB remote stub, gdbserver, now supports dynamic link libraries
863 (DLLs) on Windows and Windows CE targets.
865 * GDB now supports a faster verification that a .debug file matches its binary
866 according to its build-id signature, if the signature is present.
872 Enable or disable hardware flow control (RTS/CTS) on the serial port
873 when debugging using remote targets.
875 set mem inaccessible-by-default
876 show mem inaccessible-by-default
877 If the target supplies a memory map, for instance via the remote
878 protocol's "qXfer:memory-map:read" packet, setting this variable
879 prevents GDB from accessing memory outside the memory map. This
880 is useful for targets with memory mapped registers or which react
881 badly to accesses of unmapped address space.
883 set breakpoint auto-hw
884 show breakpoint auto-hw
885 If the target supplies a memory map, for instance via the remote
886 protocol's "qXfer:memory-map:read" packet, setting this variable
887 lets GDB use hardware breakpoints automatically for memory regions
888 where it can not use software breakpoints. This covers both the
889 "break" command and internal breakpoints used for other commands
890 including "next" and "finish".
893 catch exception unhandled
894 Stop the program execution when Ada exceptions are raised.
897 Stop the program execution when an Ada assertion failed.
901 Set an alternate system root for target files. This is a more
902 general version of "set solib-absolute-prefix", which is now
903 an alias to "set sysroot".
906 Provide extended SPU facility status information. This set of
907 commands is available only when debugging the Cell/B.E. SPU
910 * New native configurations
912 OpenBSD/sh sh*-*openbsd*
917 Use the specified local file as an XML target description, and do
918 not query the target for its built-in description.
922 OpenBSD/sh sh*-*-openbsd*
923 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
924 Toshiba Media Processor mep-elf
929 Ignore the specified signals; pass them directly to the debugged program
930 without stopping other threads or reporting them to GDB.
933 Read an XML target description from the target, which describes its
938 Read or write contents of an spufs file on the target system. These
939 packets are available only on the Cell/B.E. SPU architecture.
941 qXfer:libraries:read:
942 Report the loaded shared libraries. Combined with new "T" packet
943 response, this packet allows GDB to debug shared libraries on
944 targets where the operating system manages the list of loaded
945 libraries (e.g. Windows and SymbianOS).
949 Support for these obsolete configurations has been removed.
958 i[34567]86-*-netware*
959 i[34567]86-*-sco3.2v5*
960 i[34567]86-*-sco3.2v4*
962 i[34567]86-*-sysv4.2*
965 i[34567]86-*-unixware2*
966 i[34567]86-*-unixware*
975 * Other removed features
982 Various m68k-only ROM monitors.
989 Various Renesas ROM monitors and debugging interfaces for SH and
994 Support for a Macraigor serial interface to on-chip debugging.
995 GDB does not directly support the newer parallel or USB
1000 A debug information format. The predecessor to DWARF 2 and
1001 DWARF 3, which are still supported.
1003 Support for the HP aCC compiler on HP-UX/PA-RISC
1005 SOM-encapsulated symbolic debugging information, automatic
1006 invocation of pxdb, and the aCC custom C++ ABI. This does not
1007 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1008 with aCC can still be debugged on an assembly level.
1010 MIPS ".pdr" sections
1012 A MIPS-specific format used to describe stack frame layout
1013 in debugging information.
1017 GDB could work with an older version of Guile to debug
1018 the interpreter and Scheme programs running in it.
1020 set mips stack-arg-size
1021 set mips saved-gpreg-size
1023 Use "set mips abi" to control parameter passing for MIPS.
1025 *** Changes in GDB 6.6
1030 Cell Broadband Engine SPU spu-elf
1032 * GDB can now be configured as a cross-debugger targeting native Windows
1033 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1034 running on a Windows system over TCP/IP to debug Windows programs.
1036 * The GDB remote stub, gdbserver, has been updated to support Windows and
1037 Cygwin debugging. Both single-threaded and multi-threaded programs are
1040 * The "set trust-readonly-sections" command works again. This command was
1041 broken in GDB 6.3, 6.4, and 6.5.
1043 * The "load" command now supports writing to flash memory, if the remote
1044 stub provides the required support.
1046 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1047 longer requires symbolic debug information (e.g. DWARF-2).
1052 unset substitute-path
1053 show substitute-path
1054 Manage a list of substitution rules that GDB uses to rewrite the name
1055 of the directories where the sources are located. This can be useful
1056 for instance when the sources were moved to a different location
1057 between compilation and debugging.
1061 Print each CLI command as it is executed. Each command is prefixed with
1062 a number of `+' symbols representing the nesting depth.
1063 The source command now has a `-v' option to enable the same feature.
1067 The ARM Demon monitor support (RDP protocol, "target rdp").
1069 Kernel Object Display, an embedded debugging feature which only worked with
1070 an obsolete version of Cisco IOS.
1072 The 'set download-write-size' and 'show download-write-size' commands.
1074 * New remote packets
1077 Tell a stub about GDB client features, and request remote target features.
1078 The first feature implemented is PacketSize, which allows the target to
1079 specify the size of packets it can handle - to minimize the number of
1080 packets required and improve performance when connected to a remote
1084 Fetch an OS auxilliary vector from the remote stub. This packet is a
1085 more efficient replacement for qPart:auxv:read.
1087 qXfer:memory-map:read:
1088 Fetch a memory map from the remote stub, including information about
1089 RAM, ROM, and flash memory devices.
1094 Erase and program a flash memory device.
1096 * Removed remote packets
1099 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1100 used it, and only gdbserver implemented it.
1102 *** Changes in GDB 6.5
1106 Renesas M32C/M16C m32c-elf
1108 Morpho Technologies ms1 ms1-elf
1112 init-if-undefined Initialize a convenience variable, but
1113 only if it doesn't already have a value.
1115 The following commands are presently only implemented for native GNU/Linux:
1117 checkpoint Save a snapshot of the program state.
1119 restart <n> Return the program state to a
1120 previously saved state.
1122 info checkpoints List currently saved checkpoints.
1124 delete-checkpoint <n> Delete a previously saved checkpoint.
1126 set|show detach-on-fork Tell gdb whether to detach from a newly
1127 forked process, or to keep debugging it.
1129 info forks List forks of the user program that
1130 are available to be debugged.
1132 fork <n> Switch to debugging one of several
1133 forks of the user program that are
1134 available to be debugged.
1136 delete-fork <n> Delete a fork from the list of forks
1137 that are available to be debugged (and
1138 kill the forked process).
1140 detach-fork <n> Delete a fork from the list of forks
1141 that are available to be debugged (and
1142 allow the process to continue).
1146 Morpho Technologies ms2 ms1-elf
1148 * Improved Windows host support
1150 GDB now builds as a cross debugger hosted on i686-mingw32, including
1151 native console support, and remote communications using either
1152 network sockets or serial ports.
1154 * Improved Modula-2 language support
1156 GDB can now print most types in the Modula-2 syntax. This includes:
1157 basic types, set types, record types, enumerated types, range types,
1158 pointer types and ARRAY types. Procedure var parameters are correctly
1159 printed and hexadecimal addresses and character constants are also
1160 written in the Modula-2 syntax. Best results can be obtained by using
1161 GNU Modula-2 together with the -gdwarf-2 command line option.
1165 The ARM rdi-share module.
1167 The Netware NLM debug server.
1169 *** Changes in GDB 6.4
1171 * New native configurations
1173 OpenBSD/arm arm*-*-openbsd*
1174 OpenBSD/mips64 mips64-*-openbsd*
1178 Morpho Technologies ms1 ms1-elf
1180 * New command line options
1182 --batch-silent As for --batch, but totally silent.
1183 --return-child-result The debugger will exist with the same value
1184 the child (debugged) program exited with.
1185 --eval-command COMMAND, -ex COMMAND
1186 Execute a single GDB CLI command. This may be
1187 specified multiple times and in conjunction
1188 with the --command (-x) option.
1190 * Deprecated commands removed
1192 The following commands, that were deprecated in 2000, have been
1196 set|show arm disassembly-flavor set|show arm disassembler
1197 othernames set arm disassembler
1198 set|show remotedebug set|show debug remote
1199 set|show archdebug set|show debug arch
1200 set|show eventdebug set|show debug event
1203 * New BSD user-level threads support
1205 It is now possible to debug programs using the user-level threads
1206 library on OpenBSD and FreeBSD. Currently supported (target)
1209 FreeBSD/amd64 x86_64-*-freebsd*
1210 FreeBSD/i386 i386-*-freebsd*
1211 OpenBSD/i386 i386-*-openbsd*
1213 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1214 are not yet supported.
1216 * New support for Matsushita MN10300 w/sim added
1217 (Work in progress). mn10300-elf.
1219 * REMOVED configurations and files
1221 VxWorks and the XDR protocol *-*-vxworks
1222 Motorola MCORE mcore-*-*
1223 National Semiconductor NS32000 ns32k-*-*
1225 * New "set print array-indexes" command
1227 After turning this setting "on", GDB prints the index of each element
1228 when displaying arrays. The default is "off" to preserve the previous
1231 * VAX floating point support
1233 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1235 * User-defined command support
1237 In addition to using $arg0..$arg9 for argument passing, it is now possible
1238 to use $argc to determine now many arguments have been passed. See the
1239 section on user-defined commands in the user manual for more information.
1241 *** Changes in GDB 6.3:
1243 * New command line option
1245 GDB now accepts -l followed by a number to set the timeout for remote
1248 * GDB works with GCC -feliminate-dwarf2-dups
1250 GDB now supports a more compact representation of DWARF-2 debug
1251 information using DW_FORM_ref_addr references. These are produced
1252 by GCC with the option -feliminate-dwarf2-dups and also by some
1253 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1254 to use -feliminate-dwarf2-dups.
1256 * Internationalization
1258 When supported by the host system, GDB will be built with
1259 internationalization (libintl). The task of marking up the sources is
1260 continued, we're looking forward to our first translation.
1264 Initial support for debugging programs compiled with the GNAT
1265 implementation of the Ada programming language has been integrated
1266 into GDB. In this release, support is limited to expression evaluation.
1268 * New native configurations
1270 GNU/Linux/m32r m32r-*-linux-gnu
1274 GDB's remote protocol now includes support for the 'p' packet. This
1275 packet is used to fetch individual registers from a remote inferior.
1277 * END-OF-LIFE registers[] compatibility module
1279 GDB's internal register infrastructure has been completely rewritten.
1280 The new infrastructure making possible the implementation of key new
1281 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1284 GDB 6.3 will be the last release to include the the registers[]
1285 compatibility module that allowed out-of-date configurations to
1286 continue to work. This change directly impacts the following
1296 powerpc bdm protocol
1298 Unless there is activity to revive these configurations, they will be
1299 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1301 * OBSOLETE configurations and files
1303 Configurations that have been declared obsolete in this release have
1304 been commented out. Unless there is activity to revive these
1305 configurations, the next release of GDB will have their sources
1306 permanently REMOVED.
1315 *** Changes in GDB 6.2.1:
1317 * MIPS `break main; run' gave an heuristic-fence-post warning
1319 When attempting to run even a simple program, a warning about
1320 heuristic-fence-post being hit would be reported. This problem has
1323 * MIPS IRIX 'long double' crashed GDB
1325 When examining a long double variable, GDB would get a segmentation
1326 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1327 IRIX long double values).
1331 A bug in the VAX stack code was causing problems with the "next"
1332 command. This problem has been fixed.
1334 *** Changes in GDB 6.2:
1336 * Fix for ``many threads''
1338 On GNU/Linux systems that use the NPTL threads library, a program
1339 rapidly creating and deleting threads would confuse GDB leading to the
1342 ptrace: No such process.
1343 thread_db_get_info: cannot get thread info: generic error
1345 This problem has been fixed.
1347 * "-async" and "-noasync" options removed.
1349 Support for the broken "-noasync" option has been removed (it caused
1352 * New ``start'' command.
1354 This command runs the program until the begining of the main procedure.
1356 * New BSD Kernel Data Access Library (libkvm) interface
1358 Using ``target kvm'' it is now possible to debug kernel core dumps and
1359 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1360 platforms. Currently supported (native-only) configurations are:
1362 FreeBSD/amd64 x86_64-*-freebsd*
1363 FreeBSD/i386 i?86-*-freebsd*
1364 NetBSD/i386 i?86-*-netbsd*
1365 NetBSD/m68k m68*-*-netbsd*
1366 NetBSD/sparc sparc-*-netbsd*
1367 OpenBSD/amd64 x86_64-*-openbsd*
1368 OpenBSD/i386 i?86-*-openbsd*
1369 OpenBSD/m68k m68*-openbsd*
1370 OpenBSD/sparc sparc-*-openbsd*
1372 * Signal trampoline code overhauled
1374 Many generic problems with GDB's signal handling code have been fixed.
1375 These include: backtraces through non-contiguous stacks; recognition
1376 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1377 call; backtrace through a signal trampoline; step into and out of
1378 signal handlers; and single-stepping in the signal trampoline.
1380 Please note that kernel bugs are a limiting factor here. These
1381 features have been shown to work on an s390 GNU/Linux system that
1382 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1384 * Cygwin support for DWARF 2 added.
1386 * New native configurations
1388 GNU/Linux/hppa hppa*-*-linux*
1389 OpenBSD/hppa hppa*-*-openbsd*
1390 OpenBSD/m68k m68*-*-openbsd*
1391 OpenBSD/m88k m88*-*-openbsd*
1392 OpenBSD/powerpc powerpc-*-openbsd*
1393 NetBSD/vax vax-*-netbsd*
1394 OpenBSD/vax vax-*-openbsd*
1396 * END-OF-LIFE frame compatibility module
1398 GDB's internal frame infrastructure has been completely rewritten.
1399 The new infrastructure making it possible to support key new features
1400 including DWARF 2 Call Frame Information. To aid in the task of
1401 migrating old configurations to this new infrastructure, a
1402 compatibility module, that allowed old configurations to continue to
1403 work, was also included.
1405 GDB 6.2 will be the last release to include this frame compatibility
1406 module. This change directly impacts the following configurations:
1416 Unless there is activity to revive these configurations, they will be
1417 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1419 * REMOVED configurations and files
1421 Sun 3, running SunOS 3 m68*-*-sunos3*
1422 Sun 3, running SunOS 4 m68*-*-sunos4*
1423 Sun 2, running SunOS 3 m68000-*-sunos3*
1424 Sun 2, running SunOS 4 m68000-*-sunos4*
1425 Motorola 680x0 running LynxOS m68*-*-lynxos*
1426 AT&T 3b1/Unix pc m68*-att-*
1427 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1428 decstation mips-dec-* mips-little-*
1429 riscos mips-*-riscos* mips-*-sysv*
1430 sonymips mips-sony-*
1431 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1433 *** Changes in GDB 6.1.1:
1435 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1437 The TUI (Text-mode User Interface) is now built as part of a default
1438 GDB configuration. It is enabled by either selecting the TUI with the
1439 command line option "-i=tui" or by running the separate "gdbtui"
1440 program. For more information on the TUI, see the manual "Debugging
1443 * Pending breakpoint support (also included in GDB 6.1)
1445 Support has been added to allow you to specify breakpoints in shared
1446 libraries that have not yet been loaded. If a breakpoint location
1447 cannot be found, and the "breakpoint pending" option is set to auto,
1448 GDB queries you if you wish to make the breakpoint pending on a future
1449 shared-library load. If and when GDB resolves the breakpoint symbol,
1450 the pending breakpoint is removed as one or more regular breakpoints
1453 Pending breakpoints are very useful for GCJ Java debugging.
1455 * Fixed ISO-C build problems
1457 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1458 non ISO-C code that stopped them being built using a more strict ISO-C
1459 compiler (e.g., IBM's C compiler).
1461 * Fixed build problem on IRIX 5
1463 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1464 wasn't able to compile compile on an IRIX 5 system.
1466 * Added execute permission to gdb/gdbserver/configure
1468 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1469 permission. This bug would cause configure to fail on a number of
1470 systems (Solaris, IRIX). Ref: server/519.
1472 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1474 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1475 has been updated to use constant array sizes.
1477 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1479 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1480 its generated DWARF Call Frame Info. This encoding was causing GDB to
1481 panic, that panic has been fixed. Ref: gdb/1628.
1483 * Fixed a problem when examining parameters in shared library code.
1485 When examining parameters in optimized shared library code generated
1486 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1487 not available''. GDB now correctly displays the variable's value.
1489 *** Changes in GDB 6.1:
1491 * Removed --with-mmalloc
1493 Support for the mmalloc memory manager has been removed, as it
1494 conflicted with the internal gdb byte cache.
1496 * Changes in AMD64 configurations
1498 The AMD64 target now includes the %cs and %ss registers. As a result
1499 the AMD64 remote protocol has changed; this affects the floating-point
1500 and SSE registers. If you rely on those registers for your debugging,
1501 you should upgrade gdbserver on the remote side.
1503 * Revised SPARC target
1505 The SPARC target has been completely revised, incorporating the
1506 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1507 support for LynxOS and SunOS 4 has been dropped. Calling functions
1508 from within GDB on operating systems with a non-executable stack
1509 (Solaris, OpenBSD) now works.
1513 GDB has a new C++ demangler which does a better job on the mangled
1514 names generated by current versions of g++. It also runs faster, so
1515 with this and other changes gdb should now start faster on large C++
1518 * DWARF 2 Location Expressions
1520 GDB support for location expressions has been extended to support function
1521 arguments and frame bases. Older versions of GDB could crash when they
1524 * C++ nested types and namespaces
1526 GDB's support for nested types and namespaces in C++ has been
1527 improved, especially if you use the DWARF 2 debugging format. (This
1528 is the default for recent versions of GCC on most platforms.)
1529 Specifically, if you have a class "Inner" defined within a class or
1530 namespace "Outer", then GDB realizes that the class's name is
1531 "Outer::Inner", not simply "Inner". This should greatly reduce the
1532 frequency of complaints about not finding RTTI symbols. In addition,
1533 if you are stopped at inside of a function defined within a namespace,
1534 GDB modifies its name lookup accordingly.
1536 * New native configurations
1538 NetBSD/amd64 x86_64-*-netbsd*
1539 OpenBSD/amd64 x86_64-*-openbsd*
1540 OpenBSD/alpha alpha*-*-openbsd*
1541 OpenBSD/sparc sparc-*-openbsd*
1542 OpenBSD/sparc64 sparc64-*-openbsd*
1544 * New debugging protocols
1546 M32R with SDI protocol m32r-*-elf*
1548 * "set prompt-escape-char" command deleted.
1550 The command "set prompt-escape-char" has been deleted. This command,
1551 and its very obscure effet on GDB's prompt, was never documented,
1552 tested, nor mentioned in the NEWS file.
1554 * OBSOLETE configurations and files
1556 Configurations that have been declared obsolete in this release have
1557 been commented out. Unless there is activity to revive these
1558 configurations, the next release of GDB will have their sources
1559 permanently REMOVED.
1561 Sun 3, running SunOS 3 m68*-*-sunos3*
1562 Sun 3, running SunOS 4 m68*-*-sunos4*
1563 Sun 2, running SunOS 3 m68000-*-sunos3*
1564 Sun 2, running SunOS 4 m68000-*-sunos4*
1565 Motorola 680x0 running LynxOS m68*-*-lynxos*
1566 AT&T 3b1/Unix pc m68*-att-*
1567 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1568 decstation mips-dec-* mips-little-*
1569 riscos mips-*-riscos* mips-*-sysv*
1570 sonymips mips-sony-*
1571 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1573 * REMOVED configurations and files
1575 SGI Irix-4.x mips-sgi-irix4 or iris4
1576 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1577 Z8000 simulator z8k-zilog-none or z8ksim
1578 Matsushita MN10200 w/simulator mn10200-*-*
1579 H8/500 simulator h8500-hitachi-hms or h8500hms
1580 HP/PA running BSD hppa*-*-bsd*
1581 HP/PA running OSF/1 hppa*-*-osf*
1582 HP/PA Pro target hppa*-*-pro*
1583 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1584 386BSD i[3456]86-*-bsd*
1585 Sequent family i[3456]86-sequent-sysv4*
1586 i[3456]86-sequent-sysv*
1587 i[3456]86-sequent-bsd*
1588 SPARC running LynxOS sparc-*-lynxos*
1589 SPARC running SunOS 4 sparc-*-sunos4*
1590 Tsqware Sparclet sparclet-*-*
1591 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1593 *** Changes in GDB 6.0:
1597 Support for debugging the Objective-C programming language has been
1598 integrated into GDB.
1600 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1602 DWARF 2's Call Frame Information makes available compiler generated
1603 information that more exactly describes the program's run-time stack.
1604 By using this information, GDB is able to provide more robust stack
1607 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1608 have been updated to use a new backtrace mechanism which includes
1609 DWARF 2 CFI support.
1613 GDB's remote protocol has been extended to include support for hosted
1614 file I/O (where the remote target uses GDB's file system). See GDB's
1615 remote protocol documentation for details.
1617 * All targets using the new architecture framework.
1619 All of GDB's targets have been updated to use the new internal
1620 architecture framework. The way is now open for future GDB releases
1621 to include cross-architecture native debugging support (i386 on amd64,
1624 * GNU/Linux's Thread Local Storage (TLS)
1626 GDB now includes support for for the GNU/Linux implementation of
1627 per-thread variables.
1629 * GNU/Linux's Native POSIX Thread Library (NPTL)
1631 GDB's thread code has been updated to work with either the new
1632 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1634 * Separate debug info.
1636 GDB, in conjunction with BINUTILS, now supports a mechanism for
1637 automatically loading debug information from a separate file. Instead
1638 of shipping full debug and non-debug versions of system libraries,
1639 system integrators can now instead ship just the stripped libraries
1640 and optional debug files.
1642 * DWARF 2 Location Expressions
1644 DWARF 2 Location Expressions allow the compiler to more completely
1645 describe the location of variables (even in optimized code) to the
1648 GDB now includes preliminary support for location expressions (support
1649 for DW_OP_piece is still missing).
1653 A number of long standing bugs that caused GDB to die while starting a
1654 Java application have been fixed. GDB's Java support is now
1655 considered "useable".
1657 * GNU/Linux support for fork, vfork, and exec.
1659 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1660 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1663 * GDB supports logging output to a file
1665 There are two new commands, "set logging" and "show logging", which can be
1666 used to capture GDB's output to a file.
1668 * The meaning of "detach" has changed for gdbserver
1670 The "detach" command will now resume the application, as documented. To
1671 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1674 * d10v, m68hc11 `regs' command deprecated
1676 The `info registers' command has been updated so that it displays the
1677 registers using a format identical to the old `regs' command.
1681 A new command, "maint set profile on/off", has been added. This command can
1682 be used to enable or disable profiling while running GDB, to profile a
1683 session or a set of commands. In addition there is a new configure switch,
1684 "--enable-profiling", which will cause GDB to be compiled with profiling
1685 data, for more informative profiling results.
1687 * Default MI syntax changed to "mi2".
1689 The default MI (machine interface) syntax, enabled by the command line
1690 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1691 "mi1", can be enabled by specifying the option "-i=mi1".
1693 Support for the original "mi0" syntax (included in GDB 5.0) has been
1696 Fix for gdb/192: removed extraneous space when displaying frame level.
1697 Fix for gdb/672: update changelist is now output in mi list format.
1698 Fix for gdb/702: a -var-assign that updates the value now shows up
1699 in a subsequent -var-update.
1701 * New native configurations.
1703 FreeBSD/amd64 x86_64-*-freebsd*
1705 * Multi-arched targets.
1707 HP/PA HPUX11 hppa*-*-hpux*
1708 Renesas M32R/D w/simulator m32r-*-elf*
1710 * OBSOLETE configurations and files
1712 Configurations that have been declared obsolete in this release have
1713 been commented out. Unless there is activity to revive these
1714 configurations, the next release of GDB will have their sources
1715 permanently REMOVED.
1717 Z8000 simulator z8k-zilog-none or z8ksim
1718 Matsushita MN10200 w/simulator mn10200-*-*
1719 H8/500 simulator h8500-hitachi-hms or h8500hms
1720 HP/PA running BSD hppa*-*-bsd*
1721 HP/PA running OSF/1 hppa*-*-osf*
1722 HP/PA Pro target hppa*-*-pro*
1723 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1724 Sequent family i[3456]86-sequent-sysv4*
1725 i[3456]86-sequent-sysv*
1726 i[3456]86-sequent-bsd*
1727 Tsqware Sparclet sparclet-*-*
1728 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1730 * REMOVED configurations and files
1733 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1734 IBM AIX PS/2 i[3456]86-*-aix
1735 i386 running Mach 3.0 i[3456]86-*-mach3*
1736 i386 running Mach i[3456]86-*-mach*
1737 i386 running OSF/1 i[3456]86-*osf1mk*
1738 HP/Apollo 68k Family m68*-apollo*-sysv*,
1740 m68*-hp-bsd*, m68*-hp-hpux*
1741 Argonaut Risc Chip (ARC) arc-*-*
1742 Mitsubishi D30V d30v-*-*
1743 Fujitsu FR30 fr30-*-elf*
1744 OS/9000 i[34]86-*-os9k
1745 I960 with MON960 i960-*-coff
1747 * MIPS $fp behavior changed
1749 The convenience variable $fp, for the MIPS, now consistently returns
1750 the address of the current frame's base. Previously, depending on the
1751 context, $fp could refer to either $sp or the current frame's base
1752 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1753 The GNU Source-Level Debugger''.
1755 *** Changes in GDB 5.3:
1757 * GNU/Linux shared library multi-threaded performance improved.
1759 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1760 `/proc', in preference to `ptrace' for memory reads. This may result
1761 in an improvement in the start-up time of multi-threaded, shared
1762 library applications when run under GDB. One GDB user writes: ``loads
1763 shared libs like mad''.
1765 * ``gdbserver'' now supports multi-threaded applications on some targets
1767 Support for debugging multi-threaded applications which use
1768 the GNU/Linux LinuxThreads package has been added for
1769 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1770 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1772 * GDB now supports C/C++ preprocessor macros.
1774 GDB now expands preprocessor macro invocations in C/C++ expressions,
1775 and provides various commands for showing macro definitions and how
1778 The new command `macro expand EXPRESSION' expands any macro
1779 invocations in expression, and shows the result.
1781 The new command `show macro MACRO-NAME' shows the definition of the
1782 macro named MACRO-NAME, and where it was defined.
1784 Most compilers don't include information about macros in the debugging
1785 information by default. In GCC 3.1, for example, you need to compile
1786 your program with the options `-gdwarf-2 -g3'. If the macro
1787 information is present in the executable, GDB will read it.
1789 * Multi-arched targets.
1791 DEC Alpha (partial) alpha*-*-*
1792 DEC VAX (partial) vax-*-*
1794 National Semiconductor NS32000 (partial) ns32k-*-*
1795 Motorola 68000 (partial) m68k-*-*
1796 Motorola MCORE mcore-*-*
1800 Fujitsu FRV architecture added by Red Hat frv*-*-*
1803 * New native configurations
1805 Alpha NetBSD alpha*-*-netbsd*
1806 SH NetBSD sh*-*-netbsdelf*
1807 MIPS NetBSD mips*-*-netbsd*
1808 UltraSPARC NetBSD sparc64-*-netbsd*
1810 * OBSOLETE configurations and files
1812 Configurations that have been declared obsolete in this release have
1813 been commented out. Unless there is activity to revive these
1814 configurations, the next release of GDB will have their sources
1815 permanently REMOVED.
1817 Mitsubishi D30V d30v-*-*
1818 OS/9000 i[34]86-*-os9k
1819 IBM AIX PS/2 i[3456]86-*-aix
1820 Fujitsu FR30 fr30-*-elf*
1821 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1822 Argonaut Risc Chip (ARC) arc-*-*
1823 i386 running Mach 3.0 i[3456]86-*-mach3*
1824 i386 running Mach i[3456]86-*-mach*
1825 i386 running OSF/1 i[3456]86-*osf1mk*
1826 HP/Apollo 68k Family m68*-apollo*-sysv*,
1828 m68*-hp-bsd*, m68*-hp-hpux*
1829 I960 with MON960 i960-*-coff
1831 * OBSOLETE languages
1833 CHILL, a Pascal like language used by telecommunications companies.
1835 * REMOVED configurations and files
1837 AMD 29k family via UDI a29k-amd-udi, udi29k
1838 A29K VxWorks a29k-*-vxworks
1839 AMD 29000 embedded, using EBMON a29k-none-none
1840 AMD 29000 embedded with COFF a29k-none-coff
1841 AMD 29000 embedded with a.out a29k-none-aout
1843 testsuite/gdb.hp/gdb.threads-hp/ directory
1845 * New command "set max-user-call-depth <nnn>"
1847 This command allows the user to limit the call depth of user-defined
1848 commands. The default is 1024.
1850 * Changes in FreeBSD/i386 native debugging.
1852 Support for the "generate-core-file" has been added.
1854 * New commands "dump", "append", and "restore".
1856 These commands allow data to be copied from target memory
1857 to a bfd-format or binary file (dump and append), and back
1858 from a file into memory (restore).
1860 * Improved "next/step" support on multi-processor Alpha Tru64.
1862 The previous single-step mechanism could cause unpredictable problems,
1863 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1864 of a software single-step mechanism prevents this.
1866 *** Changes in GDB 5.2.1:
1874 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1875 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1876 Fix, by Joel Brobecker imported from mainline.
1878 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1879 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1880 Fix, by Fred Fish, imported from mainline.
1882 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1883 Surprisingly enough, it works now.
1884 By Michal Ludvig, imported from mainline.
1886 i386 hardware watchpoint support:
1887 avoid misses on second run for some targets.
1888 By Pierre Muller, imported from mainline.
1890 *** Changes in GDB 5.2:
1892 * New command "set trust-readonly-sections on[off]".
1894 This command is a hint that tells gdb that read-only sections
1895 really are read-only (ie. that their contents will not change).
1896 In this mode, gdb will go to the object file rather than the
1897 target to read memory from read-only sections (such as ".text").
1898 This can be a significant performance improvement on some
1899 (notably embedded) targets.
1901 * New command "generate-core-file" (or "gcore").
1903 This new gdb command allows the user to drop a core file of the child
1904 process state at any time. So far it's been implemented only for
1905 GNU/Linux and Solaris, but should be relatively easily ported to other
1906 hosts. Argument is core file name (defaults to core.<pid>).
1908 * New command line option
1910 GDB now accepts --pid or -p followed by a process id.
1912 * Change in command line behavior -- corefiles vs. process ids.
1914 There is a subtle behavior in the way in which GDB handles
1915 command line arguments. The first non-flag argument is always
1916 a program to debug, but the second non-flag argument may either
1917 be a corefile or a process id. Previously, GDB would attempt to
1918 open the second argument as a corefile, and if that failed, would
1919 issue a superfluous error message and then attempt to attach it as
1920 a process. Now, if the second argument begins with a non-digit,
1921 it will be treated as a corefile. If it begins with a digit,
1922 GDB will attempt to attach it as a process, and if no such process
1923 is found, will then attempt to open it as a corefile.
1925 * Changes in ARM configurations.
1927 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1928 configuration is fully multi-arch.
1930 * New native configurations
1932 ARM NetBSD arm*-*-netbsd*
1933 x86 OpenBSD i[3456]86-*-openbsd*
1934 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1935 Sparc64 running FreeBSD sparc64-*-freebsd*
1939 Sanyo XStormy16 xstormy16-elf
1941 * OBSOLETE configurations and files
1943 Configurations that have been declared obsolete in this release have
1944 been commented out. Unless there is activity to revive these
1945 configurations, the next release of GDB will have their sources
1946 permanently REMOVED.
1948 AMD 29k family via UDI a29k-amd-udi, udi29k
1949 A29K VxWorks a29k-*-vxworks
1950 AMD 29000 embedded, using EBMON a29k-none-none
1951 AMD 29000 embedded with COFF a29k-none-coff
1952 AMD 29000 embedded with a.out a29k-none-aout
1954 testsuite/gdb.hp/gdb.threads-hp/ directory
1956 * REMOVED configurations and files
1958 TI TMS320C80 tic80-*-*
1960 PowerPC Solaris powerpcle-*-solaris*
1961 PowerPC Windows NT powerpcle-*-cygwin32
1962 PowerPC Netware powerpc-*-netware*
1963 Harris/CXUX m88k m88*-harris-cxux*
1964 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1965 ns32k-utek-sysv* ns32k-utek-*
1966 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1967 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1968 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1969 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1970 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1972 * Changes to command line processing
1974 The new `--args' feature can be used to specify command-line arguments
1975 for the inferior from gdb's command line.
1977 * Changes to key bindings
1979 There is a new `operate-and-get-next' function bound to `C-o'.
1981 *** Changes in GDB 5.1.1
1983 Fix compile problem on DJGPP.
1985 Fix a problem with floating-point registers on the i386 being
1988 Fix to stop GDB crashing on .debug_str debug info.
1990 Numerous documentation fixes.
1992 Numerous testsuite fixes.
1994 *** Changes in GDB 5.1:
1996 * New native configurations
1998 Alpha FreeBSD alpha*-*-freebsd*
1999 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2000 MIPS GNU/Linux mips*-*-linux*
2001 MIPS SGI Irix 6.x mips*-sgi-irix6*
2002 ia64 AIX ia64-*-aix*
2003 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2007 Motorola 68HC11 and 68HC12 m68hc11-elf
2009 UltraSparc running GNU/Linux sparc64-*-linux*
2011 * OBSOLETE configurations and files
2013 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2014 Harris/CXUX m88k m88*-harris-cxux*
2015 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2016 ns32k-utek-sysv* ns32k-utek-*
2017 TI TMS320C80 tic80-*-*
2019 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2020 PowerPC Solaris powerpcle-*-solaris*
2021 PowerPC Windows NT powerpcle-*-cygwin32
2022 PowerPC Netware powerpc-*-netware*
2023 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2024 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2025 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2026 Apple Macintosh (MPW) host N/A
2028 stuff.c (Program to stuff files into a specially prepared space in kdb)
2029 kdb-start.c (Main loop for the standalone kernel debugger)
2031 Configurations that have been declared obsolete in this release have
2032 been commented out. Unless there is activity to revive these
2033 configurations, the next release of GDB will have their sources
2034 permanently REMOVED.
2036 * REMOVED configurations and files
2038 Altos 3068 m68*-altos-*
2039 Convex c1-*-*, c2-*-*
2041 ARM RISCix arm-*-* (as host)
2045 * GDB has been converted to ISO C.
2047 GDB's source code has been converted to ISO C. In particular, the
2048 sources are fully protoized, and rely on standard headers being
2053 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2055 * The MI enabled by default.
2057 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2058 revised and enabled by default. Packages which use GDB as a debugging
2059 engine behind a UI or another front end are encouraged to switch to
2060 using the GDB/MI interface, instead of the old annotations interface
2061 which is now deprecated.
2063 * Support for debugging Pascal programs.
2065 GDB now includes support for debugging Pascal programs. The following
2066 main features are supported:
2068 - Pascal-specific data types such as sets;
2070 - automatic recognition of Pascal sources based on file-name
2073 - Pascal-style display of data types, variables, and functions;
2075 - a Pascal expression parser.
2077 However, some important features are not yet supported.
2079 - Pascal string operations are not supported at all;
2081 - there are some problems with boolean types;
2083 - Pascal type hexadecimal constants are not supported
2084 because they conflict with the internal variables format;
2086 - support for Pascal objects and classes is not full yet;
2088 - unlike Pascal, GDB is case-sensitive for symbol names.
2090 * Changes in completion.
2092 Commands such as `shell', `run' and `set args', which pass arguments
2093 to inferior programs, now complete on file names, similar to what
2094 users expect at the shell prompt.
2096 Commands which accept locations, such as `disassemble', `print',
2097 `breakpoint', `until', etc. now complete on filenames as well as
2098 program symbols. Thus, if you type "break foob TAB", and the source
2099 files linked into the programs include `foobar.c', that file name will
2100 be one of the candidates for completion. However, file names are not
2101 considered for completion after you typed a colon that delimits a file
2102 name from a name of a function in that file, as in "break foo.c:bar".
2104 `set demangle-style' completes on available demangling styles.
2106 * New platform-independent commands:
2108 It is now possible to define a post-hook for a command as well as a
2109 hook that runs before the command. For more details, see the
2110 documentation of `hookpost' in the GDB manual.
2112 * Changes in GNU/Linux native debugging.
2114 Support for debugging multi-threaded programs has been completely
2115 revised for all platforms except m68k and sparc. You can now debug as
2116 many threads as your system allows you to have.
2118 Attach/detach is supported for multi-threaded programs.
2120 Support for SSE registers was added for x86. This doesn't work for
2121 multi-threaded programs though.
2123 * Changes in MIPS configurations.
2125 Multi-arch support is enabled for all MIPS configurations.
2127 GDB can now be built as native debugger on SGI Irix 6.x systems for
2128 debugging n32 executables. (Debugging 64-bit executables is not yet
2131 * Unified support for hardware watchpoints in all x86 configurations.
2133 Most (if not all) native x86 configurations support hardware-assisted
2134 breakpoints and watchpoints in a unified manner. This support
2135 implements debug register sharing between watchpoints, which allows to
2136 put a virtually infinite number of watchpoints on the same address,
2137 and also supports watching regions up to 16 bytes with several debug
2140 The new maintenance command `maintenance show-debug-regs' toggles
2141 debugging print-outs in functions that insert, remove, and test
2142 watchpoints and hardware breakpoints.
2144 * Changes in the DJGPP native configuration.
2146 New command ``info dos sysinfo'' displays assorted information about
2147 the CPU, OS, memory, and DPMI server.
2149 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2150 display information about segment descriptors stored in GDT, LDT, and
2153 New commands ``info dos pde'' and ``info dos pte'' display entries
2154 from Page Directory and Page Tables (for now works with CWSDPMI only).
2155 New command ``info dos address-pte'' displays the Page Table entry for
2156 a given linear address.
2158 GDB can now pass command lines longer than 126 characters to the
2159 program being debugged (requires an update to the libdbg.a library
2160 which is part of the DJGPP development kit).
2162 DWARF2 debug info is now supported.
2164 It is now possible to `step' and `next' through calls to `longjmp'.
2166 * Changes in documentation.
2168 All GDB documentation was converted to GFDL, the GNU Free
2169 Documentation License.
2171 Tracepoints-related commands are now fully documented in the GDB
2174 TUI, the Text-mode User Interface, is now documented in the manual.
2176 Tracepoints-related commands are now fully documented in the GDB
2179 The "GDB Internals" manual now has an index. It also includes
2180 documentation of `ui_out' functions, GDB coding standards, x86
2181 hardware watchpoints, and memory region attributes.
2183 * GDB's version number moved to ``version.in''
2185 The Makefile variable VERSION has been replaced by the file
2186 ``version.in''. People creating GDB distributions should update the
2187 contents of this file.
2191 GUD support is now a standard part of the EMACS distribution.
2193 *** Changes in GDB 5.0:
2195 * Improved support for debugging FP programs on x86 targets
2197 Unified and much-improved support for debugging floating-point
2198 programs on all x86 targets. In particular, ``info float'' now
2199 displays the FP registers in the same format on all x86 targets, with
2200 greater level of detail.
2202 * Improvements and bugfixes in hardware-assisted watchpoints
2204 It is now possible to watch array elements, struct members, and
2205 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2206 on x86 targets no longer erroneously trigger when the address is
2209 * Improvements in the native DJGPP version of GDB
2211 The distribution now includes all the scripts and auxiliary files
2212 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2213 machines ``out of the box''.
2215 The DJGPP version can now debug programs that use signals. It is
2216 possible to catch signals that happened in the debuggee, deliver
2217 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2218 would kill the program being debugged.) Programs that hook hardware
2219 interrupts (keyboard, timer, etc.) can also be debugged.
2221 It is now possible to debug DJGPP programs that redirect their
2222 standard handles or switch them to raw (as opposed to cooked) mode, or
2223 even close them. The command ``run < foo > bar'' works as expected,
2224 and ``info terminal'' reports useful information about the debuggee's
2225 terminal, including raw/cooked mode, redirection, etc.
2227 The DJGPP version now uses termios functions for console I/O, which
2228 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2231 DOS-style file names with drive letters are now fully supported by
2234 It is now possible to debug DJGPP programs that switch their working
2235 directory. It is also possible to rerun the debuggee any number of
2236 times without restarting GDB; thus, you can use the same setup,
2237 breakpoints, etc. for many debugging sessions.
2239 * New native configurations
2241 ARM GNU/Linux arm*-*-linux*
2242 PowerPC GNU/Linux powerpc-*-linux*
2246 Motorola MCore mcore-*-*
2247 x86 VxWorks i[3456]86-*-vxworks*
2248 PowerPC VxWorks powerpc-*-vxworks*
2249 TI TMS320C80 tic80-*-*
2251 * OBSOLETE configurations
2253 Altos 3068 m68*-altos-*
2254 Convex c1-*-*, c2-*-*
2256 ARM RISCix arm-*-* (as host)
2259 Configurations that have been declared obsolete will be commented out,
2260 but the code will be left in place. If there is no activity to revive
2261 these configurations before the next release of GDB, the sources will
2262 be permanently REMOVED.
2264 * Gould support removed
2266 Support for the Gould PowerNode and NP1 has been removed.
2268 * New features for SVR4
2270 On SVR4 native platforms (such as Solaris), if you attach to a process
2271 without first loading a symbol file, GDB will now attempt to locate and
2272 load symbols from the running process's executable file.
2274 * Many C++ enhancements
2276 C++ support has been greatly improved. Overload resolution now works properly
2277 in almost all cases. RTTI support is on the way.
2279 * Remote targets can connect to a sub-program
2281 A popen(3) style serial-device has been added. This device starts a
2282 sub-process (such as a stand-alone simulator) and then communicates
2283 with that. The sub-program to run is specified using the syntax
2284 ``|<program> <args>'' vis:
2286 (gdb) set remotedebug 1
2287 (gdb) target extended-remote |mn10300-elf-sim program-args
2289 * MIPS 64 remote protocol
2291 A long standing bug in the mips64 remote protocol where by GDB
2292 expected certain 32 bit registers (ex SR) to be transfered as 32
2293 instead of 64 bits has been fixed.
2295 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2296 added to provide backward compatibility with older versions of GDB.
2298 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2300 The command ``set remotebinarydownload'' command has been replaced by
2301 ``set remote X-packet''. Other commands in ``set remote'' family
2302 include ``set remote P-packet''.
2304 * Breakpoint commands accept ranges.
2306 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2307 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2308 ``tracepoint passcount'' also accepts a range of tracepoints.
2310 * ``apropos'' command added.
2312 The ``apropos'' command searches through command names and
2313 documentation strings, printing out matches, making it much easier to
2314 try to find a command that does what you are looking for.
2318 A new machine oriented interface (MI) has been added to GDB. This
2319 interface is designed for debug environments running GDB as a separate
2320 process. This is part of the long term libGDB project. See the
2321 "GDB/MI" chapter of the GDB manual for further information. It can be
2322 enabled by configuring with:
2324 .../configure --enable-gdbmi
2326 *** Changes in GDB-4.18:
2328 * New native configurations
2330 HP-UX 10.20 hppa*-*-hpux10.20
2331 HP-UX 11.x hppa*-*-hpux11.0*
2332 M68K GNU/Linux m68*-*-linux*
2336 Fujitsu FR30 fr30-*-elf*
2337 Intel StrongARM strongarm-*-*
2338 Mitsubishi D30V d30v-*-*
2340 * OBSOLETE configurations
2342 Gould PowerNode, NP1 np1-*-*, pn-*-*
2344 Configurations that have been declared obsolete will be commented out,
2345 but the code will be left in place. If there is no activity to revive
2346 these configurations before the next release of GDB, the sources will
2347 be permanently REMOVED.
2351 As a compatibility experiment, GDB's source files buildsym.h and
2352 buildsym.c have been converted to pure standard C, no longer
2353 containing any K&R compatibility code. We believe that all systems in
2354 use today either come with a standard C compiler, or have a GCC port
2355 available. If this is not true, please report the affected
2356 configuration to bug-gdb@gnu.org immediately. See the README file for
2357 information about getting a standard C compiler if you don't have one
2362 GDB now uses readline 2.2.
2364 * set extension-language
2366 You can now control the mapping between filename extensions and source
2367 languages by using the `set extension-language' command. For instance,
2368 you can ask GDB to treat .c files as C++ by saying
2369 set extension-language .c c++
2370 The command `info extensions' lists all of the recognized extensions
2371 and their associated languages.
2373 * Setting processor type for PowerPC and RS/6000
2375 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2376 you can use the `set processor' command to specify what variant of the
2377 PowerPC family you are debugging. The command
2381 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2382 following PowerPC and RS6000 variants:
2384 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2385 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2387 403GC IBM PowerPC 403GC
2388 505 Motorola PowerPC 505
2389 860 Motorola PowerPC 860 or 850
2390 601 Motorola PowerPC 601
2391 602 Motorola PowerPC 602
2392 603 Motorola/IBM PowerPC 603 or 603e
2393 604 Motorola PowerPC 604 or 604e
2394 750 Motorola/IBM PowerPC 750 or 750
2396 At the moment, this command just tells GDB what to name the
2397 special-purpose processor registers. Since almost all the affected
2398 registers are inaccessible to user-level programs, this command is
2399 only useful for remote debugging in its present form.
2403 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2404 more extensive support for HP-UX. Added features include shared
2405 library support, kernel threads and hardware watchpoints for 11.00,
2406 support for HP's ANSI C and C++ compilers, and a compatibility mode
2407 for xdb and dbx commands.
2411 HP's donation includes the new concept of catchpoints, which is a
2412 generalization of the old catch command. On HP-UX, it is now possible
2413 to catch exec, fork, and vfork, as well as library loading.
2415 This means that the existing catch command has changed; its first
2416 argument now specifies the type of catch to be set up. See the
2417 output of "help catch" for a list of catchpoint types.
2419 * Debugging across forks
2421 On HP-UX, you can choose which process to debug when a fork() happens
2426 HP has donated a curses-based terminal user interface (TUI). To get
2427 it, build with --enable-tui. Although this can be enabled for any
2428 configuration, at present it only works for native HP debugging.
2430 * GDB remote protocol additions
2432 A new protocol packet 'X' that writes binary data is now available.
2433 Default behavior is to try 'X', then drop back to 'M' if the stub
2434 fails to respond. The settable variable `remotebinarydownload'
2435 allows explicit control over the use of 'X'.
2437 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2438 full 64-bit address. The command
2440 set remoteaddresssize 32
2442 can be used to revert to the old behaviour. For existing remote stubs
2443 the change should not be noticed, as the additional address information
2446 In order to assist in debugging stubs, you may use the maintenance
2447 command `packet' to send any text string to the stub. For instance,
2449 maint packet heythere
2451 sends the packet "$heythere#<checksum>". Note that it is very easy to
2452 disrupt a debugging session by sending the wrong packet at the wrong
2455 The compare-sections command allows you to compare section data on the
2456 target to what is in the executable file without uploading or
2457 downloading, by comparing CRC checksums.
2459 * Tracing can collect general expressions
2461 You may now collect general expressions at tracepoints. This requires
2462 further additions to the target-side stub; see tracepoint.c and
2463 doc/agentexpr.texi for further details.
2465 * mask-address variable for Mips
2467 For Mips targets, you may control the zeroing of the upper 32 bits of
2468 a 64-bit address by entering `set mask-address on'. This is mainly
2469 of interest to users of embedded R4xxx and R5xxx processors.
2471 * Higher serial baud rates
2473 GDB's serial code now allows you to specify baud rates 57600, 115200,
2474 230400, and 460800 baud. (Note that your host system may not be able
2475 to achieve all of these rates.)
2479 The i960 configuration now includes an initial implementation of a
2480 builtin simulator, contributed by Jim Wilson.
2483 *** Changes in GDB-4.17:
2485 * New native configurations
2487 Alpha GNU/Linux alpha*-*-linux*
2488 Unixware 2.x i[3456]86-unixware2*
2489 Irix 6.x mips*-sgi-irix6*
2490 PowerPC GNU/Linux powerpc-*-linux*
2491 PowerPC Solaris powerpcle-*-solaris*
2492 Sparc GNU/Linux sparc-*-linux*
2493 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2497 Argonaut Risc Chip (ARC) arc-*-*
2498 Hitachi H8/300S h8300*-*-*
2499 Matsushita MN10200 w/simulator mn10200-*-*
2500 Matsushita MN10300 w/simulator mn10300-*-*
2501 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2502 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2503 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2504 Mitsubishi D10V w/simulator d10v-*-*
2505 Mitsubishi M32R/D w/simulator m32r-*-elf*
2506 Tsqware Sparclet sparclet-*-*
2507 NEC V850 w/simulator v850-*-*
2509 * New debugging protocols
2511 ARM with RDI protocol arm*-*-*
2512 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2513 DDB and LSI variants of PMON protocol mips*-*-*
2514 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2515 PowerPC with SDS protocol powerpc{,le}-*-eabi
2516 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2520 All configurations can now understand and use the DWARF 2 debugging
2521 format. The choice is automatic, if the symbol file contains DWARF 2
2526 GDB now includes basic Java language support. This support is
2527 only useful with Java compilers that produce native machine code.
2529 * solib-absolute-prefix and solib-search-path
2531 For SunOS and SVR4 shared libraries, you may now set the prefix for
2532 loading absolute shared library symbol files, and the search path for
2533 locating non-absolute shared library symbol files.
2535 * Live range splitting
2537 GDB can now effectively debug code for which GCC has performed live
2538 range splitting as part of its optimization. See gdb/doc/LRS for
2539 more details on the expected format of the stabs information.
2543 GDB's support for the GNU Hurd, including thread debugging, has been
2544 updated to work with current versions of the Hurd.
2548 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2549 instruction set. ARM GDB automatically detects when Thumb
2550 instructions are in use, and adjusts disassembly and backtracing
2555 GDB's MIPS target configurations now handle the MIP16 16-bit
2560 GDB now includes support for overlays; if an executable has been
2561 linked such that multiple sections are based at the same address, GDB
2562 will decide which section to use for symbolic info. You can choose to
2563 control the decision manually, using overlay commands, or implement
2564 additional target-side support and use "overlay load-target" to bring
2565 in the overlay mapping. Do "help overlay" for more detail.
2569 The command "info symbol <address>" displays information about
2570 the symbol at the specified address.
2574 The standard remote protocol now includes an extension that allows
2575 asynchronous collection and display of trace data. This requires
2576 extensive support in the target-side debugging stub. Tracing mode
2577 includes a new interaction mode in GDB and new commands: see the
2578 file tracepoint.c for more details.
2582 Configurations for embedded MIPS now include a simulator contributed
2583 by Cygnus Solutions. The simulator supports the instruction sets
2584 of most MIPS variants.
2588 Sparc configurations may now include the ERC32 simulator contributed
2589 by the European Space Agency. The simulator is not built into
2590 Sparc targets by default; configure with --enable-sim to include it.
2594 For target configurations that may include multiple variants of a
2595 basic architecture (such as MIPS and SH), you may now set the
2596 architecture explicitly. "set arch" sets, "info arch" lists
2597 the possible architectures.
2599 *** Changes in GDB-4.16:
2601 * New native configurations
2603 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2604 M68K NetBSD m68k-*-netbsd*
2605 PowerPC AIX 4.x powerpc-*-aix*
2606 PowerPC MacOS powerpc-*-macos*
2607 PowerPC Windows NT powerpcle-*-cygwin32
2608 RS/6000 AIX 4.x rs6000-*-aix4*
2612 ARM with RDP protocol arm-*-*
2613 I960 with MON960 i960-*-coff
2614 MIPS VxWorks mips*-*-vxworks*
2615 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2616 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2618 Matra Sparclet sparclet-*-*
2622 The powerpc-eabi configuration now includes the PSIM simulator,
2623 contributed by Andrew Cagney, with assistance from Mike Meissner.
2624 PSIM is a very elaborate model of the PowerPC, including not only
2625 basic instruction set execution, but also details of execution unit
2626 performance and I/O hardware. See sim/ppc/README for more details.
2630 GDB now works with Solaris 2.5.
2632 * Windows 95/NT native
2634 GDB will now work as a native debugger on Windows 95 and Windows NT.
2635 To build it from source, you must use the "gnu-win32" environment,
2636 which uses a DLL to emulate enough of Unix to run the GNU tools.
2637 Further information, binaries, and sources are available at
2638 ftp.cygnus.com, under pub/gnu-win32.
2640 * dont-repeat command
2642 If a user-defined command includes the command `dont-repeat', then the
2643 command will not be repeated if the user just types return. This is
2644 useful if the command is time-consuming to run, so that accidental
2645 extra keystrokes don't run the same command many times.
2647 * Send break instead of ^C
2649 The standard remote protocol now includes an option to send a break
2650 rather than a ^C to the target in order to interrupt it. By default,
2651 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2653 * Remote protocol timeout
2655 The standard remote protocol includes a new variable `remotetimeout'
2656 that allows you to set the number of seconds before GDB gives up trying
2657 to read from the target. The default value is 2.
2659 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2661 By default GDB will automatically keep track of objects as they are
2662 loaded and unloaded by the dynamic linker. By using the command `set
2663 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2664 when shared library events occur, thus allowing you to set breakpoints
2665 in shared libraries which are explicitly loaded by the inferior.
2667 Note this feature does not work on hpux8. On hpux9 you must link
2668 /usr/lib/end.o into your program. This feature should work
2669 automatically on hpux10.
2671 * Irix 5.x hardware watchpoint support
2673 Irix 5 configurations now support the use of hardware watchpoints.
2675 * Mips protocol "SYN garbage limit"
2677 When debugging a Mips target using the `target mips' protocol, you
2678 may set the number of characters that GDB will ignore by setting
2679 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2680 every character. The default value is 1050.
2682 * Recording and replaying remote debug sessions
2684 If you set `remotelogfile' to the name of a file, gdb will write to it
2685 a recording of a remote debug session. This recording may then be
2686 replayed back to gdb using "gdbreplay". See gdbserver/README for
2687 details. This is useful when you have a problem with GDB while doing
2688 remote debugging; you can make a recording of the session and send it
2689 to someone else, who can then recreate the problem.
2691 * Speedups for remote debugging
2693 GDB includes speedups for downloading and stepping MIPS systems using
2694 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2695 and more efficient S-record downloading.
2697 * Memory use reductions and statistics collection
2699 GDB now uses less memory and reports statistics about memory usage.
2700 Try the `maint print statistics' command, for example.
2702 *** Changes in GDB-4.15:
2704 * Psymtabs for XCOFF
2706 The symbol reader for AIX GDB now uses partial symbol tables. This
2707 can greatly improve startup time, especially for large executables.
2709 * Remote targets use caching
2711 Remote targets now use a data cache to speed up communication with the
2712 remote side. The data cache could lead to incorrect results because
2713 it doesn't know about volatile variables, thus making it impossible to
2714 debug targets which use memory mapped I/O devices. `set remotecache
2715 off' turns the the data cache off.
2717 * Remote targets may have threads
2719 The standard remote protocol now includes support for multiple threads
2720 in the target system, using new protocol commands 'H' and 'T'. See
2721 gdb/remote.c for details.
2725 If GDB is configured with `--enable-netrom', then it will include
2726 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2727 acts as though it is a bank of ROM on the target board, but you can
2728 write into it over the network. GDB's support consists only of
2729 support for fast loading into the emulated ROM; to debug, you must use
2730 another protocol, such as standard remote protocol. The usual
2731 sequence is something like
2733 target nrom <netrom-hostname>
2735 target remote <netrom-hostname>:1235
2739 GDB now includes support for the Apple Macintosh, as a host only. It
2740 may be run as either an MPW tool or as a standalone application, and
2741 it can debug through the serial port. All the usual GDB commands are
2742 available, but to the target command, you must supply "serial" as the
2743 device type instead of "/dev/ttyXX". See mpw-README in the main
2744 directory for more information on how to build. The MPW configuration
2745 scripts */mpw-config.in support only a few targets, and only the
2746 mips-idt-ecoff target has been tested.
2750 GDB configuration now uses autoconf. This is not user-visible,
2751 but does simplify configuration and building.
2755 GDB now supports hpux10.
2757 *** Changes in GDB-4.14:
2759 * New native configurations
2761 x86 FreeBSD i[345]86-*-freebsd
2762 x86 NetBSD i[345]86-*-netbsd
2763 NS32k NetBSD ns32k-*-netbsd
2764 Sparc NetBSD sparc-*-netbsd
2768 A29K VxWorks a29k-*-vxworks
2769 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2770 CPU32 EST-300 emulator m68*-*-est*
2771 PowerPC ELF powerpc-*-elf
2774 * Alpha OSF/1 support for procfs
2776 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2777 possible to attach to running processes. As the mounting of the /proc
2778 filesystem is optional on the Alpha, GDB automatically determines
2779 the availability of /proc during startup. This can lead to problems
2780 if /proc is unmounted after GDB has been started.
2782 * Arguments to user-defined commands
2784 User commands may accept up to 10 arguments separated by whitespace.
2785 Arguments are accessed within the user command via $arg0..$arg9. A
2788 print $arg0 + $arg1 + $arg2
2790 To execute the command use:
2793 Defines the command "adder" which prints the sum of its three arguments.
2794 Note the arguments are text substitutions, so they may reference variables,
2795 use complex expressions, or even perform inferior function calls.
2797 * New `if' and `while' commands
2799 This makes it possible to write more sophisticated user-defined
2800 commands. Both commands take a single argument, which is the
2801 expression to evaluate, and must be followed by the commands to
2802 execute, one per line, if the expression is nonzero, the list being
2803 terminated by the word `end'. The `if' command list may include an
2804 `else' word, which causes the following commands to be executed only
2805 if the expression is zero.
2807 * Fortran source language mode
2809 GDB now includes partial support for Fortran 77. It will recognize
2810 Fortran programs and can evaluate a subset of Fortran expressions, but
2811 variables and functions may not be handled correctly. GDB will work
2812 with G77, but does not yet know much about symbols emitted by other
2815 * Better HPUX support
2817 Most debugging facilities now work on dynamic executables for HPPAs
2818 running hpux9 or later. You can attach to running dynamically linked
2819 processes, but by default the dynamic libraries will be read-only, so
2820 for instance you won't be able to put breakpoints in them. To change
2821 that behavior do the following before running the program:
2827 This will cause the libraries to be mapped private and read-write.
2828 To revert to the normal behavior, do this:
2834 You cannot set breakpoints or examine data in the library until after
2835 the library is loaded if the function/data symbols do not have
2838 GDB can now also read debug symbols produced by the HP C compiler on
2839 HPPAs (sorry, no C++, Fortran or 68k support).
2841 * Target byte order now dynamically selectable
2843 You can choose which byte order to use with a target system, via the
2844 commands "set endian big" and "set endian little", and you can see the
2845 current setting by using "show endian". You can also give the command
2846 "set endian auto", in which case GDB will use the byte order
2847 associated with the executable. Currently, only embedded MIPS
2848 configurations support dynamic selection of target byte order.
2850 * New DOS host serial code
2852 This version uses DPMI interrupts to handle buffered I/O, so you
2853 no longer need to run asynctsr when debugging boards connected to
2856 *** Changes in GDB-4.13:
2858 * New "complete" command
2860 This lists all the possible completions for the rest of the line, if it
2861 were to be given as a command itself. This is intended for use by emacs.
2863 * Trailing space optional in prompt
2865 "set prompt" no longer adds a space for you after the prompt you set. This
2866 allows you to set a prompt which ends in a space or one that does not.
2868 * Breakpoint hit counts
2870 "info break" now displays a count of the number of times the breakpoint
2871 has been hit. This is especially useful in conjunction with "ignore"; you
2872 can ignore a large number of breakpoint hits, look at the breakpoint info
2873 to see how many times the breakpoint was hit, then run again, ignoring one
2874 less than that number, and this will get you quickly to the last hit of
2877 * Ability to stop printing at NULL character
2879 "set print null-stop" will cause GDB to stop printing the characters of
2880 an array when the first NULL is encountered. This is useful when large
2881 arrays actually contain only short strings.
2883 * Shared library breakpoints
2885 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2886 breakpoints in shared libraries before the executable is run.
2888 * Hardware watchpoints
2890 There is a new hardware breakpoint for the watch command for sparclite
2891 targets. See gdb/sparclite/hw_breakpoint.note.
2893 Hardware watchpoints are also now supported under GNU/Linux.
2897 Annotations have been added. These are for use with graphical interfaces,
2898 and are still experimental. Currently only gdba.el uses these.
2900 * Improved Irix 5 support
2902 GDB now works properly with Irix 5.2.
2904 * Improved HPPA support
2906 GDB now works properly with the latest GCC and GAS.
2908 * New native configurations
2910 Sequent PTX4 i[34]86-sequent-ptx4
2911 HPPA running OSF/1 hppa*-*-osf*
2912 Atari TT running SVR4 m68*-*-sysv4*
2913 RS/6000 LynxOS rs6000-*-lynxos*
2917 OS/9000 i[34]86-*-os9k
2918 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2921 * Hitachi SH7000 and E7000-PC ICE support
2923 There is now support for communicating with the Hitachi E7000-PC ICE.
2924 This is available automatically when GDB is configured for the SH.
2928 As usual, a variety of small fixes and improvements, both generic
2929 and configuration-specific. See the ChangeLog for more detail.
2931 *** Changes in GDB-4.12:
2933 * Irix 5 is now supported
2937 GDB-4.12 on the HPPA has a number of changes which make it unable
2938 to debug the output from the currently released versions of GCC and
2939 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2940 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2941 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2944 *** Changes in GDB-4.11:
2946 * User visible changes:
2950 The "set remotedebug" option is now consistent between the mips remote
2951 target, remote targets using the gdb-specific protocol, UDI (AMD's
2952 debug protocol for the 29k) and the 88k bug monitor. It is now an
2953 integer specifying a debug level (normally 0 or 1, but 2 means more
2954 debugging info for the mips target).
2956 * DEC Alpha native support
2958 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2959 debug info, but GDB works fairly well with the DEC compiler and should
2960 work with a future GCC release. See the README file for a few
2961 Alpha-specific notes.
2963 * Preliminary thread implementation
2965 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2967 * LynxOS native and target support for 386
2969 This release has been hosted on LynxOS 2.2, and also can be configured
2970 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
2973 * Improvements in C++ mangling/demangling.
2975 This release has much better g++ debugging, specifically in name
2976 mangling/demangling, virtual function calls, print virtual table,
2977 call methods, ...etc.
2979 *** Changes in GDB-4.10:
2981 * User visible changes:
2983 Remote debugging using the GDB-specific (`target remote') protocol now
2984 supports the `load' command. This is only useful if you have some
2985 other way of getting the stub to the target system, and you can put it
2986 somewhere in memory where it won't get clobbered by the download.
2988 Filename completion now works.
2990 When run under emacs mode, the "info line" command now causes the
2991 arrow to point to the line specified. Also, "info line" prints
2992 addresses in symbolic form (as well as hex).
2994 All vxworks based targets now support a user settable option, called
2995 vxworks-timeout. This option represents the number of seconds gdb
2996 should wait for responses to rpc's. You might want to use this if
2997 your vxworks target is, perhaps, a slow software simulator or happens
2998 to be on the far side of a thin network line.
3002 This release contains support for using a DEC alpha as a GDB host for
3003 cross debugging. Native alpha debugging is not supported yet.
3006 *** Changes in GDB-4.9:
3010 This is the first GDB release which is accompanied by a matching testsuite.
3011 The testsuite requires installation of dejagnu, which should be available
3012 via ftp from most sites that carry GNU software.
3016 'Cfront' style demangling has had its name changed to 'ARM' style, to
3017 emphasize that it was written from the specifications in the C++ Annotated
3018 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3019 disclaimers, it still generated too much confusion with users attempting to
3020 use gdb with AT&T cfront.
3024 GDB now uses a standard remote interface to a simulator library.
3025 So far, the library contains simulators for the Zilog Z8001/2, the
3026 Hitachi H8/300, H8/500 and Super-H.
3028 * New targets supported
3030 H8/300 simulator h8300-hitachi-hms or h8300hms
3031 H8/500 simulator h8500-hitachi-hms or h8500hms
3032 SH simulator sh-hitachi-hms or sh
3033 Z8000 simulator z8k-zilog-none or z8ksim
3034 IDT MIPS board over serial line mips-idt-ecoff
3036 Cross-debugging to GO32 targets is supported. It requires a custom
3037 version of the i386-stub.c module which is integrated with the
3038 GO32 memory extender.
3040 * New remote protocols
3042 MIPS remote debugging protocol.
3044 * New source languages supported
3046 This version includes preliminary support for Chill, a Pascal like language
3047 used by telecommunications companies. Chill support is also being integrated
3048 into the GNU compiler, but we don't know when it will be publically available.
3051 *** Changes in GDB-4.8:
3053 * HP Precision Architecture supported
3055 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3056 version of this support was available as a set of patches from the
3057 University of Utah. GDB does not support debugging of programs
3058 compiled with the HP compiler, because HP will not document their file
3059 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3060 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3062 Many problems in the preliminary version have been fixed.
3064 * Faster and better demangling
3066 We have improved template demangling and fixed numerous bugs in the GNU style
3067 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3068 character types (wchar_t) are now supported. Demangling of each symbol is now
3069 only done once, and is cached when the symbol table for a file is read in.
3070 This results in a small increase in memory usage for C programs, a moderate
3071 increase in memory usage for C++ programs, and a fantastic speedup in
3074 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3075 from the specifications in the Annotated Reference Manual, which AT&T's
3076 compiler does not actually implement.
3078 * G++ multiple inheritance compiler problem
3080 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3081 inheritance lattices was reworked to properly discover ambiguities. We
3082 recently found an example which causes this new algorithm to fail in a
3083 very subtle way, producing bad debug information for those classes.
3084 The file 'gcc.patch' (in this directory) can be applied to gcc to
3085 circumvent the problem. A future GCC release will contain a complete
3088 The previous G++ debug info problem (mentioned below for the gdb-4.7
3089 release) is fixed in gcc version 2.3.2.
3091 * Improved configure script
3093 The `configure' script will now attempt to guess your system type if
3094 you don't supply a host system type. The old scheme of supplying a
3095 host system triplet is preferable over using this. All the magic is
3096 done in the new `config.guess' script. Examine it for details.
3098 We have also brought our configure script much more in line with the FSF's
3099 version. It now supports the --with-xxx options. In particular,
3100 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3101 The resulting GDB will not be able to read arbitrary object file formats --
3102 only the format ``expected'' to be used on the configured target system.
3103 We hope to make this the default in a future release.
3105 * Documentation improvements
3107 There's new internal documentation on how to modify GDB, and how to
3108 produce clean changes to the code. We implore people to read it
3109 before submitting changes.
3111 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3112 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3113 `info' files are also provided. To build `info' files from scratch,
3114 you will need the latest `makeinfo' release, which will be available in
3115 a future texinfo-X.Y release.
3117 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3118 We're not sure exactly which versions have this problem, but it has
3119 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3120 or better. If that isn't possible, there is a patch in
3121 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3122 around this problem.
3126 GDB now supports array constants that can be used in expressions typed in by
3127 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3128 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3131 The new directory `gdb/sparclite' contains a program that demonstrates
3132 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3134 * New native hosts supported
3136 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3137 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3139 * New targets supported
3141 AMD 29k family via UDI a29k-amd-udi or udi29k
3143 * New file formats supported
3145 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3146 HPUX core files, and SCO 3.2v2 core files.
3150 Attaching to processes now works again; thanks for the many bug reports.
3152 We have also stomped on a bunch of core dumps caused by
3153 printf_filtered("%s") problems.
3155 We eliminated a copyright problem on the rpc and ptrace header files
3156 for VxWorks, which was discovered at the last minute during the 4.7
3157 release. You should now be able to build a VxWorks GDB.
3159 You can now interrupt gdb while an attached process is running. This
3160 will cause the attached process to stop, and give control back to GDB.
3162 We fixed problems caused by using too many file descriptors
3163 for reading symbols from object files and libraries. This was
3164 especially a problem for programs that used many (~100) shared
3167 The `step' command now only enters a subroutine if there is line number
3168 information for the subroutine. Otherwise it acts like the `next'
3169 command. Previously, `step' would enter subroutines if there was
3170 any debugging information about the routine. This avoids problems
3171 when using `cc -g1' on MIPS machines.
3173 * Internal improvements
3175 GDB's internal interfaces have been improved to make it easier to support
3176 debugging of multiple languages in the future.
3178 GDB now uses a common structure for symbol information internally.
3179 Minimal symbols (derived from linkage symbols in object files), partial
3180 symbols (from a quick scan of debug information), and full symbols
3181 contain a common subset of information, making it easier to write
3182 shared code that handles any of them.
3184 * New command line options
3186 We now accept --silent as an alias for --quiet.
3190 The memory-mapped-malloc library is now licensed under the GNU Library
3191 General Public License.
3193 *** Changes in GDB-4.7:
3195 * Host/native/target split
3197 GDB has had some major internal surgery to untangle the support for
3198 hosts and remote targets. Now, when you configure GDB for a remote
3199 target, it will no longer load in all of the support for debugging
3200 local programs on the host. When fully completed and tested, this will
3201 ensure that arbitrary host/target combinations are possible.
3203 The primary conceptual shift is to separate the non-portable code in
3204 GDB into three categories. Host specific code is required any time GDB
3205 is compiled on that host, regardless of the target. Target specific
3206 code relates to the peculiarities of the target, but can be compiled on
3207 any host. Native specific code is everything else: it can only be
3208 built when the host and target are the same system. Child process
3209 handling and core file support are two common `native' examples.
3211 GDB's use of /proc for controlling Unix child processes is now cleaner.
3212 It has been split out into a single module under the `target_ops' vector,
3213 plus two native-dependent functions for each system that uses /proc.
3215 * New hosts supported
3217 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3218 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3219 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3221 * New targets supported
3223 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3224 68030 and CPU32 m68030-*-*, m68332-*-*
3226 * New native hosts supported
3228 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3229 (386bsd is not well tested yet)
3230 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3232 * New file formats supported
3234 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3235 supports reading of `a.out.adobe' object files, which are an a.out
3236 format extended with minimal information about multiple sections.
3240 `show copying' is the same as the old `info copying'.
3241 `show warranty' is the same as `info warrantee'.
3242 These were renamed for consistency. The old commands continue to work.
3244 `info handle' is a new alias for `info signals'.
3246 You can now define pre-command hooks, which attach arbitrary command
3247 scripts to any command. The commands in the hook will be executed
3248 prior to the user's command. You can also create a hook which will be
3249 executed whenever the program stops. See gdb.texinfo.
3253 We now deal with Cfront style name mangling, and can even extract type
3254 info from mangled symbols. GDB can automatically figure out which
3255 symbol mangling style your C++ compiler uses.
3257 Calling of methods and virtual functions has been improved as well.
3261 The crash that occured when debugging Sun Ansi-C compiled binaries is
3262 fixed. This was due to mishandling of the extra N_SO stabs output
3265 We also finally got Ultrix 4.2 running in house, and fixed core file
3266 support, with help from a dozen people on the net.
3268 John M. Farrell discovered that the reason that single-stepping was so
3269 slow on all of the Mips based platforms (primarily SGI and DEC) was
3270 that we were trying to demangle and lookup a symbol used for internal
3271 purposes on every instruction that was being stepped through. Changing
3272 the name of that symbol so that it couldn't be mistaken for a C++
3273 mangled symbol sped things up a great deal.
3275 Rich Pixley sped up symbol lookups in general by getting much smarter
3276 about when C++ symbol mangling is necessary. This should make symbol
3277 completion (TAB on the command line) much faster. It's not as fast as
3278 we'd like, but it's significantly faster than gdb-4.6.
3282 A new user controllable variable 'call_scratch_address' can
3283 specify the location of a scratch area to be used when GDB
3284 calls a function in the target. This is necessary because the
3285 usual method of putting the scratch area on the stack does not work
3286 in systems that have separate instruction and data spaces.
3288 We integrated changes to support the 29k UDI (Universal Debugger
3289 Interface), but discovered at the last minute that we didn't have all
3290 of the appropriate copyright paperwork. We are working with AMD to
3291 resolve this, and hope to have it available soon.
3295 We have sped up the remote serial line protocol, especially for targets
3296 with lots of registers. It now supports a new `expedited status' ('T')
3297 message which can be used in place of the existing 'S' status message.
3298 This allows the remote stub to send only the registers that GDB
3299 needs to make a quick decision about single-stepping or conditional
3300 breakpoints, eliminating the need to fetch the entire register set for
3301 each instruction being stepped through.
3303 The GDB remote serial protocol now implements a write-through cache for
3304 registers, only re-reading the registers if the target has run.
3306 There is also a new remote serial stub for SPARC processors. You can
3307 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3308 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3309 processor with a serial port.
3313 Configure.in files have become much easier to read and modify. A new
3314 `table driven' format makes it more obvious what configurations are
3315 supported, and what files each one uses.
3319 There is a new opcodes library which will eventually contain all of the
3320 disassembly routines and opcode tables. At present, it only contains
3321 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3322 disassembler (binutils/objdump) to share these routines.
3324 The libiberty library is now copylefted under the GNU Library General
3325 Public License. This allows more liberal use, and was done so libg++
3326 can use it. This makes no difference to GDB, since the Library License
3327 grants all the rights from the General Public License.
3331 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3332 reference to the stabs symbol info used by the debugger. It is (as far
3333 as we know) the only published document on this fascinating topic. We
3334 encourage you to read it, compare it to the stabs information on your
3335 system, and send improvements on the document in general (to
3336 bug-gdb@prep.ai.mit.edu).
3338 And, of course, many bugs have been fixed.
3341 *** Changes in GDB-4.6:
3343 * Better support for C++ function names
3345 GDB now accepts as input the "demangled form" of C++ overloaded function
3346 names and member function names, and can do command completion on such names
3347 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3348 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3349 Make use of command completion, it is your friend.
3351 GDB also now accepts a variety of C++ mangled symbol formats. They are
3352 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3353 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3354 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3355 for the list of formats.
3357 * G++ symbol mangling problem
3359 Recent versions of gcc have a bug in how they emit debugging information for
3360 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3361 directory) can be applied to gcc to fix the problem. Alternatively, if you
3362 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3363 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3364 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3367 * New 'maintenance' command
3369 All of the commands related to hacking GDB internals have been moved out of
3370 the main command set, and now live behind the 'maintenance' command. This
3371 can also be abbreviated as 'mt'. The following changes were made:
3373 dump-me -> maintenance dump-me
3374 info all-breakpoints -> maintenance info breakpoints
3375 printmsyms -> maintenance print msyms
3376 printobjfiles -> maintenance print objfiles
3377 printpsyms -> maintenance print psymbols
3378 printsyms -> maintenance print symbols
3380 The following commands are new:
3382 maintenance demangle Call internal GDB demangler routine to
3383 demangle a C++ link name and prints the result.
3384 maintenance print type Print a type chain for a given symbol
3386 * Change to .gdbinit file processing
3388 We now read the $HOME/.gdbinit file before processing the argv arguments
3389 (e.g. reading symbol files or core files). This allows global parameters to
3390 be set, which will apply during the symbol reading. The ./.gdbinit is still
3391 read after argv processing.
3393 * New hosts supported
3395 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3397 GNU/Linux support i386-unknown-linux or linux
3399 We are also including code to support the HP/PA running BSD and HPUX. This
3400 is almost guaranteed not to work, as we didn't have time to test or build it
3401 for this release. We are including it so that the more adventurous (or
3402 masochistic) of you can play with it. We also had major problems with the
3403 fact that the compiler that we got from HP doesn't support the -g option.
3406 * New targets supported
3408 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3410 * More smarts about finding #include files
3412 GDB now remembers the compilation directory for all include files, and for
3413 all files from which C is generated (like yacc and lex sources). This
3414 greatly improves GDB's ability to find yacc/lex sources, and include files,
3415 especially if you are debugging your program from a directory different from
3416 the one that contains your sources.
3418 We also fixed a bug which caused difficulty with listing and setting
3419 breakpoints in include files which contain C code. (In the past, you had to
3420 try twice in order to list an include file that you hadn't looked at before.)
3422 * Interesting infernals change
3424 GDB now deals with arbitrary numbers of sections, where the symbols for each
3425 section must be relocated relative to that section's landing place in the
3426 target's address space. This work was needed to support ELF with embedded
3427 stabs used by Solaris-2.0.
3429 * Bug fixes (of course!)
3431 There have been loads of fixes for the following things:
3432 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3433 i960, stabs, DOS(GO32), procfs, etc...
3435 See the ChangeLog for details.
3437 *** Changes in GDB-4.5:
3439 * New machines supported (host and target)
3441 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3443 SGI Irix-4.x mips-sgi-irix4 or iris4
3445 * New malloc package
3447 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3448 Mmalloc is capable of handling mutiple heaps of memory. It is also
3449 capable of saving a heap to a file, and then mapping it back in later.
3450 This can be used to greatly speedup the startup of GDB by using a
3451 pre-parsed symbol table which lives in a mmalloc managed heap. For
3452 more details, please read mmalloc/mmalloc.texi.
3456 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3457 'help info proc' for details.
3459 * MIPS ecoff symbol table format
3461 The code that reads MIPS symbol table format is now supported on all hosts.
3462 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3465 * File name changes for MS-DOS
3467 Many files in the config directories have been renamed to make it easier to
3468 support GDB on MS-DOSe systems (which have very restrictive file name
3469 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3470 environment) is close to working but has some remaining problems. Note
3471 that debugging of DOS programs is not supported, due to limitations
3472 in the ``operating system'', but it can be used to host cross-debugging.
3474 * Cross byte order fixes
3476 Many fixes have been made to support cross debugging of Sparc and MIPS
3477 targets from hosts whose byte order differs.
3479 * New -mapped and -readnow options
3481 If memory-mapped files are available on your system through the 'mmap'
3482 system call, you can use the -mapped option on the `file' or
3483 `symbol-file' commands to cause GDB to write the symbols from your
3484 program into a reusable file. If the program you are debugging is
3485 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3486 Future GDB debugging sessions will notice the presence of this file,
3487 and will quickly map in symbol information from it, rather than reading
3488 the symbol table from the executable program. Using the '-mapped'
3489 option in a GDB `file' or `symbol-file' command has the same effect as
3490 starting GDB with the '-mapped' command-line option.
3492 You can cause GDB to read the entire symbol table immediately by using
3493 the '-readnow' option with any of the commands that load symbol table
3494 information (or on the GDB command line). This makes the command
3495 slower, but makes future operations faster.
3497 The -mapped and -readnow options are typically combined in order to
3498 build a `fred.syms' file that contains complete symbol information.
3499 A simple GDB invocation to do nothing but build a `.syms' file for future
3502 gdb -batch -nx -mapped -readnow programname
3504 The `.syms' file is specific to the host machine on which GDB is run.
3505 It holds an exact image of GDB's internal symbol table. It cannot be
3506 shared across multiple host platforms.
3508 * longjmp() handling
3510 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3511 siglongjmp() without losing control. This feature has not yet been ported to
3512 all systems. It currently works on many 386 platforms, all MIPS-based
3513 platforms (SGI, DECstation, etc), and Sun3/4.
3517 Preliminary work has been put in to support the new Solaris OS from Sun. At
3518 this time, it can control and debug processes, but it is not capable of
3523 As always, many many bug fixes. The major areas were with g++, and mipsread.
3524 People using the MIPS-based platforms should experience fewer mysterious
3525 crashes and trashed symbol tables.
3527 *** Changes in GDB-4.4:
3529 * New machines supported (host and target)
3531 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3533 BSD Reno on Vax vax-dec-bsd
3534 Ultrix on Vax vax-dec-ultrix
3536 * New machines supported (target)
3538 AMD 29000 embedded, using EBMON a29k-none-none
3542 GDB continues to improve its handling of C++. `References' work better.
3543 The demangler has also been improved, and now deals with symbols mangled as
3544 per the Annotated C++ Reference Guide.
3546 GDB also now handles `stabs' symbol information embedded in MIPS
3547 `ecoff' symbol tables. Since the ecoff format was not easily
3548 extensible to handle new languages such as C++, this appeared to be a
3549 good way to put C++ debugging info into MIPS binaries. This option
3550 will be supported in the GNU C compiler, version 2, when it is
3553 * New features for SVR4
3555 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3556 shared libraries. Debugging dynamically linked programs should present
3557 only minor differences from debugging statically linked programs.
3559 The `info proc' command will print out information about any process
3560 on an SVR4 system (including the one you are debugging). At the moment,
3561 it prints the address mappings of the process.
3563 If you bring up GDB on another SVR4 system, please send mail to
3564 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3566 * Better dynamic linking support in SunOS
3568 Reading symbols from shared libraries which contain debugging symbols
3569 now works properly. However, there remain issues such as automatic
3570 skipping of `transfer vector' code during function calls, which
3571 make it harder to debug code in a shared library, than to debug the
3572 same code linked statically.
3576 GDB is now using the latest `getopt' routines from the FSF. This
3577 version accepts the -- prefix for options with long names. GDB will
3578 continue to accept the old forms (-option and +option) as well.
3579 Various single letter abbreviations for options have been explicity
3580 added to the option table so that they won't get overshadowed in the
3581 future by other options that begin with the same letter.
3585 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3586 Many assorted bugs have been handled. Many more remain to be handled.
3587 See the various ChangeLog files (primarily in gdb and bfd) for details.
3590 *** Changes in GDB-4.3:
3592 * New machines supported (host and target)
3594 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3595 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3596 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3598 * Almost SCO Unix support
3600 We had hoped to support:
3601 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3602 (except for core file support), but we discovered very late in the release
3603 that it has problems with process groups that render gdb unusable. Sorry
3604 about that. I encourage people to fix it and post the fixes.
3606 * Preliminary ELF and DWARF support
3608 GDB can read ELF object files on System V Release 4, and can handle
3609 debugging records for C, in DWARF format, in ELF files. This support
3610 is preliminary. If you bring up GDB on another SVR4 system, please
3611 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3616 GDB now uses the latest `readline' library. One user-visible change
3617 is that two tabs will list possible command completions, which previously
3618 required typing M-? (meta-question mark, or ESC ?).
3622 The `stepi' bug that many of you noticed has been squashed.
3623 Many bugs in C++ have been handled. Many more remain to be handled.
3624 See the various ChangeLog files (primarily in gdb and bfd) for details.
3626 * State of the MIPS world (in case you wondered):
3628 GDB can understand the symbol tables emitted by the compilers
3629 supplied by most vendors of MIPS-based machines, including DEC. These
3630 symbol tables are in a format that essentially nobody else uses.
3632 Some versions of gcc come with an assembler post-processor called
3633 mips-tfile. This program is required if you want to do source-level
3634 debugging of gcc-compiled programs. I believe FSF does not ship
3635 mips-tfile with gcc version 1, but it will eventually come with gcc
3638 Debugging of g++ output remains a problem. g++ version 1.xx does not
3639 really support it at all. (If you're lucky, you should be able to get
3640 line numbers and stack traces to work, but no parameters or local
3641 variables.) With some work it should be possible to improve the
3644 When gcc version 2 is released, you will have somewhat better luck.
3645 However, even then you will get confusing results for inheritance and
3648 We will eventually provide full debugging of g++ output on
3649 DECstations. This will probably involve some kind of stabs-in-ecoff
3650 encapulation, but the details have not been worked out yet.
3653 *** Changes in GDB-4.2:
3655 * Improved configuration
3657 Only one copy of `configure' exists now, and it is not self-modifying.
3658 Porting BFD is simpler.
3662 The `step' and `next' commands now only stop at the first instruction
3663 of a source line. This prevents the multiple stops that used to occur
3664 in switch statements, for-loops, etc. `Step' continues to stop if a
3665 function that has debugging information is called within the line.
3669 Lots of small bugs fixed. More remain.
3671 * New host supported (not target)
3673 Intel 386 PC clone running Mach i386-none-mach
3676 *** Changes in GDB-4.1:
3678 * Multiple source language support
3680 GDB now has internal scaffolding to handle several source languages.
3681 It determines the type of each source file from its filename extension,
3682 and will switch expression parsing and number formatting to match the
3683 language of the function in the currently selected stack frame.
3684 You can also specifically set the language to be used, with
3685 `set language c' or `set language modula-2'.
3689 GDB now has preliminary support for the GNU Modula-2 compiler,
3690 currently under development at the State University of New York at
3691 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3692 continue through the fall of 1991 and into 1992.
3694 Other Modula-2 compilers are currently not supported, and attempting to
3695 debug programs compiled with them will likely result in an error as the
3696 symbol table is read. Feel free to work on it, though!
3698 There are hooks in GDB for strict type checking and range checking,
3699 in the `Modula-2 philosophy', but they do not currently work.
3703 GDB can now write to executable and core files (e.g. patch
3704 a variable's value). You must turn this switch on, specify
3705 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3706 by assigning a new value to a variable. Modifications take
3709 * Automatic SunOS shared library reading
3711 When you run your program, GDB automatically determines where its
3712 shared libraries (if any) have been loaded, and reads their symbols.
3713 The `share' command is no longer needed. This also works when
3714 examining core files.
3718 You can specify the number of lines that the `list' command shows.
3721 * New machines supported (host and target)
3723 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3724 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3725 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3727 * New hosts supported (not targets)
3729 IBM RT/PC: romp-ibm-aix or rtpc
3731 * New targets supported (not hosts)
3733 AMD 29000 embedded with COFF a29k-none-coff
3734 AMD 29000 embedded with a.out a29k-none-aout
3735 Ultracomputer remote kernel debug a29k-nyu-kern
3737 * New remote interfaces
3743 *** Changes in GDB-4.0:
3747 Wide output is wrapped at good places to make the output more readable.
3749 Gdb now supports cross-debugging from a host machine of one type to a
3750 target machine of another type. Communication with the target system
3751 is over serial lines. The ``target'' command handles connecting to the
3752 remote system; the ``load'' command will download a program into the
3753 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3754 also supports debugging of realtime processes running under VxWorks,
3755 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3756 stub on the target system.
3758 New CPUs supported include the AMD 29000 and Intel 960.
3760 GDB now reads object files and symbol tables via a ``binary file''
3761 library, which allows a single copy of GDB to debug programs of multiple
3762 object file types such as a.out and coff.
3764 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3765 refcard.dvi and refcard.ps are available to format it).
3768 * Control-Variable user interface simplified
3770 All variables that control the operation of the debugger can be set
3771 by the ``set'' command, and displayed by the ``show'' command.
3773 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3774 ``Show prompt'' produces the response:
3775 Gdb's prompt is new-gdb=>.
3777 What follows are the NEW set commands. The command ``help set'' will
3778 print a complete list of old and new set commands. ``help set FOO''
3779 will give a longer description of the variable FOO. ``show'' will show
3780 all of the variable descriptions and their current settings.
3782 confirm on/off: Enables warning questions for operations that are
3783 hard to recover from, e.g. rerunning the program while
3784 it is already running. Default is ON.
3786 editing on/off: Enables EMACS style command line editing
3787 of input. Previous lines can be recalled with
3788 control-P, the current line can be edited with control-B,
3789 you can search for commands with control-R, etc.
3792 history filename NAME: NAME is where the gdb command history
3793 will be stored. The default is .gdb_history,
3794 or the value of the environment variable
3797 history size N: The size, in commands, of the command history. The
3798 default is 256, or the value of the environment variable
3801 history save on/off: If this value is set to ON, the history file will
3802 be saved after exiting gdb. If set to OFF, the
3803 file will not be saved. The default is OFF.
3805 history expansion on/off: If this value is set to ON, then csh-like
3806 history expansion will be performed on
3807 command line input. The default is OFF.
3809 radix N: Sets the default radix for input and output. It can be set
3810 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3811 in the current radix, so "set radix 10" is always a no-op.
3813 height N: This integer value is the number of lines on a page. Default
3814 is 24, the current `stty rows'' setting, or the ``li#''
3815 setting from the termcap entry matching the environment
3818 width N: This integer value is the number of characters on a line.
3819 Default is 80, the current `stty cols'' setting, or the ``co#''
3820 setting from the termcap entry matching the environment
3823 Note: ``set screensize'' is obsolete. Use ``set height'' and
3824 ``set width'' instead.
3826 print address on/off: Print memory addresses in various command displays,
3827 such as stack traces and structure values. Gdb looks
3828 more ``symbolic'' if you turn this off; it looks more
3829 ``machine level'' with it on. Default is ON.
3831 print array on/off: Prettyprint arrays. New convenient format! Default
3834 print demangle on/off: Print C++ symbols in "source" form if on,
3837 print asm-demangle on/off: Same, for assembler level printouts
3840 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3843 * Support for Epoch Environment.
3845 The epoch environment is a version of Emacs v18 with windowing. One
3846 new command, ``inspect'', is identical to ``print'', except that if you
3847 are running in the epoch environment, the value is printed in its own
3851 * Support for Shared Libraries
3853 GDB can now debug programs and core files that use SunOS shared libraries.
3854 Symbols from a shared library cannot be referenced
3855 before the shared library has been linked with the program (this
3856 happens after you type ``run'' and before the function main() is entered).
3857 At any time after this linking (including when examining core files
3858 from dynamically linked programs), gdb reads the symbols from each
3859 shared library when you type the ``sharedlibrary'' command.
3860 It can be abbreviated ``share''.
3862 sharedlibrary REGEXP: Load shared object library symbols for files
3863 matching a unix regular expression. No argument
3864 indicates to load symbols for all shared libraries.
3866 info sharedlibrary: Status of loaded shared libraries.
3871 A watchpoint stops execution of a program whenever the value of an
3872 expression changes. Checking for this slows down execution
3873 tremendously whenever you are in the scope of the expression, but is
3874 quite useful for catching tough ``bit-spreader'' or pointer misuse
3875 problems. Some machines such as the 386 have hardware for doing this
3876 more quickly, and future versions of gdb will use this hardware.
3878 watch EXP: Set a watchpoint (breakpoint) for an expression.
3880 info watchpoints: Information about your watchpoints.
3882 delete N: Deletes watchpoint number N (same as breakpoints).
3883 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3884 enable N: Re-enables watchpoint number N (same as breakpoints).
3887 * C++ multiple inheritance
3889 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3892 * C++ exception handling
3894 Gdb now supports limited C++ exception handling. Besides the existing
3895 ability to breakpoint on an exception handler, gdb can breakpoint on
3896 the raising of an exception (before the stack is peeled back to the
3899 catch FOO: If there is a FOO exception handler in the dynamic scope,
3900 set a breakpoint to catch exceptions which may be raised there.
3901 Multiple exceptions (``catch foo bar baz'') may be caught.
3903 info catch: Lists all exceptions which may be caught in the
3904 current stack frame.
3907 * Minor command changes
3909 The command ``call func (arg, arg, ...)'' now acts like the print
3910 command, except it does not print or save a value if the function's result
3911 is void. This is similar to dbx usage.
3913 The ``up'' and ``down'' commands now always print the frame they end up
3914 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3915 frames without printing.
3917 * New directory command
3919 'dir' now adds directories to the FRONT of the source search path.
3920 The path starts off empty. Source files that contain debug information
3921 about the directory in which they were compiled can be found even
3922 with an empty path; Sun CC and GCC include this information. If GDB can't
3923 find your source file in the current directory, type "dir .".
3925 * Configuring GDB for compilation
3927 For normal use, type ``./configure host''. See README or gdb.texinfo
3930 GDB now handles cross debugging. If you are remotely debugging between
3931 two different machines, type ``./configure host -target=targ''.
3932 Host is the machine where GDB will run; targ is the machine
3933 where the program that you are debugging will run.