1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.2
8 ** GDB values in Python are now callable if the value represents a
9 function. For example, if 'some_value' represents a function that
10 takes two integer parameters and returns a value, you can call
11 that function like so:
13 result = some_value (10,20)
17 ** GDB now puts template parameters in scope when debugging in an
18 instantiation. For example, if you have:
20 template<int X> int func (void) { return X; }
22 then if you step into func<5>, "print X" will show "5". This
23 feature requires proper debuginfo support from the compiler; it
26 * GDB now has some support for using labels in the program's source in
27 linespecs. For instance, you can use "advance label" to continue
30 * GDB now has support for reading and writing a new .gdb_index
31 section. This section holds a fast index of DWARF debugging
32 information and can be used to greatly speed up GDB startup and
33 operation. See the documentation for `save gdb-index' for details.
35 * The "watch" command now accepts an optional "-location" argument.
36 When used, this causes GDB to watch the memory referred to by the
37 expression. Such a watchpoint is never deleted due to it going out
40 *** Changes in GDB 7.2
42 * Shared library support for remote targets by default
44 When GDB is configured for a generic, non-OS specific target, like
45 for example, --target=arm-eabi or one of the many *-*-elf targets,
46 GDB now queries remote stubs for loaded shared libraries using the
47 `qXfer:libraries:read' packet. Previously, shared library support
48 was always disabled for such configurations.
52 ** Argument Dependent Lookup (ADL)
54 In C++ ADL lookup directs function search to the namespaces of its
55 arguments even if the namespace has not been imported.
65 Here the compiler will search for `foo' in the namespace of 'b'
66 and find A::foo. GDB now supports this. This construct is commonly
67 used in the Standard Template Library for operators.
69 ** Improved User Defined Operator Support
71 In addition to member operators, GDB now supports lookup of operators
72 defined in a namespace and imported with a `using' directive, operators
73 defined in the global scope, operators imported implicitly from an
74 anonymous namespace, and the ADL operators mentioned in the previous
76 GDB now also supports proper overload resolution for all the previously
77 mentioned flavors of operators.
79 ** static const class members
81 Printing of static const class members that are initialized in the
82 class definition has been fixed.
84 * Windows Thread Information Block access.
86 On Windows targets, GDB now supports displaying the Windows Thread
87 Information Block (TIB) structure. This structure is visible either
88 by using the new command `info w32 thread-information-block' or, by
89 dereferencing the new convenience variable named `$_tlb', a
90 thread-specific pointer to the TIB. This feature is also supported
91 when remote debugging using GDBserver.
95 Static tracepoints are calls in the user program into a tracing
96 library. One such library is a port of the LTTng kernel tracer to
97 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
98 When debugging with GDBserver, GDB now supports combining the GDB
99 tracepoint machinery with such libraries. For example: the user can
100 use GDB to probe a static tracepoint marker (a call from the user
101 program into the tracing library) with the new "strace" command (see
102 "New commands" below). This creates a "static tracepoint" in the
103 breakpoint list, that can be manipulated with the same feature set
104 as fast and regular tracepoints. E.g., collect registers, local and
105 global variables, collect trace state variables, and define
106 tracepoint conditions. In addition, the user can collect extra
107 static tracepoint marker specific data, by collecting the new
108 $_sdata internal variable. When analyzing the trace buffer, you can
109 inspect $_sdata like any other variable available to GDB. For more
110 information, see the "Tracepoints" chapter in GDB user manual. New
111 remote packets have been defined to support static tracepoints, see
112 the "New remote packets" section below.
118 Return the address of the Windows Thread Information Block of a given thread.
122 In response to several of the tracepoint packets, the target may now
123 also respond with a number of intermediate `qRelocInsn' request
124 packets before the final result packet, to have GDB handle
125 relocating an instruction to execute at a different address. This
126 is particularly useful for stubs that support fast tracepoints. GDB
127 reports support for this feature in the qSupported packet.
131 List static tracepoint markers in the target program.
135 List static tracepoint markers at a given address in the target
138 qXfer:statictrace:read
140 Read the static trace data collected (by a `collect $_sdata'
141 tracepoint action). The remote stub reports support for this packet
142 to gdb's qSupported query.
144 * The source command now accepts a -s option to force searching for the
145 script in the source search path even if the script name specifies
148 * New features in the GDB remote stub, GDBserver
150 - GDBserver now support tracepoints (including fast tracepoints, and
151 static tracepoints). The feature is currently supported by the
152 i386-linux and amd64-linux builds. See the "Tracepoints support
153 in gdbserver" section in the manual for more information.
155 GDBserver JIT compiles the tracepoint's conditional agent
156 expression bytecode into native code whenever possible for low
157 overhead dynamic tracepoints conditionals. For such tracepoints,
158 an expression that examines program state is evaluated when the
159 tracepoint is reached, in order to determine whether to capture
160 trace data. If the condition is simple and false, processing the
161 tracepoint finishes very quickly and no data is gathered.
163 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
164 for static tracepoints support.
166 - GDBserver now supports x86_64 Windows 64-bit debugging.
168 * GDB now sends xmlRegisters= in qSupported packet to indicate that
169 it understands register description.
171 * The --batch flag now disables pagination and queries.
173 * X86 general purpose registers
175 GDB now supports reading/writing byte, word and double-word x86
176 general purpose registers directly. This means you can use, say,
177 $ah or $ax to refer, respectively, to the byte register AH and
178 16-bit word register AX that are actually portions of the 32-bit
179 register EAX or 64-bit register RAX.
181 * The `commands' command now accepts a range of breakpoints to modify.
182 A plain `commands' following a command that creates multiple
183 breakpoints affects all the breakpoints set by that command. This
184 applies to breakpoints set by `rbreak', and also applies when a
185 single `break' command creates multiple breakpoints (e.g.,
186 breakpoints on overloaded c++ functions).
188 * The `rbreak' command now accepts a filename specification as part of
189 its argument, limiting the functions selected by the regex to those
190 in the specified file.
192 * Support for remote debugging Windows and SymbianOS shared libraries
193 from Unix hosts has been improved. Non Windows GDB builds now can
194 understand target reported file names that follow MS-DOS based file
195 system semantics, such as file names that include drive letters and
196 use the backslash character as directory separator. This makes it
197 possible to transparently use the "set sysroot" and "set
198 solib-search-path" on Unix hosts to point as host copies of the
199 target's shared libraries. See the new command "set
200 target-file-system-kind" described below, and the "Commands to
201 specify files" section in the user manual for more information.
205 eval template, expressions...
206 Convert the values of one or more expressions under the control
207 of the string template to a command line, and call it.
209 set target-file-system-kind unix|dos-based|auto
210 show target-file-system-kind
211 Set or show the assumed file system kind for target reported file
214 save breakpoints <filename>
215 Save all current breakpoint definitions to a file suitable for use
216 in a later debugging session. To read the saved breakpoint
217 definitions, use the `source' command.
219 `save tracepoints' is a new alias for `save-tracepoints'. The latter
222 info static-tracepoint-markers
223 Display information about static tracepoint markers in the target.
225 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
226 Define a static tracepoint by probing a marker at the given
227 function, line, address, or marker ID.
232 The disassemble command now supports "start,+length" form of two arguments.
236 ** GDB now provides a new directory location, called the python directory,
237 where Python scripts written for GDB can be installed. The location
238 of that directory is <data-directory>/python, where <data-directory>
239 is the GDB data directory. For more details, see section `Scripting
240 GDB using Python' in the manual.
242 ** The GDB Python API now has access to breakpoints, symbols, symbol
243 tables, program spaces, inferiors, threads and frame's code blocks.
244 Additionally, GDB Parameters can now be created from the API, and
245 manipulated via set/show in the CLI.
247 ** New functions gdb.target_charset, gdb.target_wide_charset,
248 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
250 ** New exception gdb.GdbError.
252 ** Pretty-printers are now also looked up in the current program space.
254 ** Pretty-printers can now be individually enabled and disabled.
256 ** GDB now looks for names of Python scripts to auto-load in a
257 special section named `.debug_gdb_scripts', in addition to looking
258 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
260 * Tracepoint actions were unified with breakpoint commands. In particular,
261 there are no longer differences in "info break" output for breakpoints and
262 tracepoints and the "commands" command can be used for both tracepoints and
267 ARM Symbian arm*-*-symbianelf*
269 * D language support.
270 GDB now supports debugging programs written in the D programming
273 * GDB now supports the extended ptrace interface for PowerPC which is
274 available since Linux kernel version 2.6.34. This automatically enables
275 any hardware breakpoints and additional hardware watchpoints available in
276 the processor. The old ptrace interface exposes just one hardware
277 watchpoint and no hardware breakpoints.
279 * GDB is now able to use the Data Value Compare (DVC) register available on
280 embedded PowerPC processors to implement in hardware simple watchpoint
281 conditions of the form:
283 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
285 This works in native GDB running on Linux kernels with the extended ptrace
286 interface mentioned above.
288 *** Changes in GDB 7.1
294 GDB now supports importing of namespaces in C++. This enables the
295 user to inspect variables from imported namespaces. Support for
296 namepace aliasing has also been added. So, if a namespace is
297 aliased in the current scope (e.g. namepace C=A; ) the user can
298 print variables using the alias (e.g. (gdb) print C::x).
302 All known bugs relating to the printing of virtual base class were
303 fixed. It is now possible to call overloaded static methods using a
308 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
309 and reinterpret_cast<> are now handled by the C++ expression parser.
313 Xilinx MicroBlaze microblaze-*-*
318 Xilinx MicroBlaze microblaze
321 * Multi-program debugging.
323 GDB now has support for multi-program (a.k.a. multi-executable or
324 multi-exec) debugging. This allows for debugging multiple inferiors
325 simultaneously each running a different program under the same GDB
326 session. See "Debugging Multiple Inferiors and Programs" in the
327 manual for more information. This implied some user visible changes
328 in the multi-inferior support. For example, "info inferiors" now
329 lists inferiors that are not running yet or that have exited
330 already. See also "New commands" and "New options" below.
332 * New tracing features
334 GDB's tracepoint facility now includes several new features:
336 ** Trace state variables
338 GDB tracepoints now include support for trace state variables, which
339 are variables managed by the target agent during a tracing
340 experiment. They are useful for tracepoints that trigger each
341 other, so for instance one tracepoint can count hits in a variable,
342 and then a second tracepoint has a condition that is true when the
343 count reaches a particular value. Trace state variables share the
344 $-syntax of GDB convenience variables, and can appear in both
345 tracepoint actions and condition expressions. Use the "tvariable"
346 command to create, and "info tvariables" to view; see "Trace State
347 Variables" in the manual for more detail.
351 GDB now includes an option for defining fast tracepoints, which
352 targets may implement more efficiently, such as by installing a jump
353 into the target agent rather than a trap instruction. The resulting
354 speedup can be by two orders of magnitude or more, although the
355 tradeoff is that some program locations on some target architectures
356 might not allow fast tracepoint installation, for instance if the
357 instruction to be replaced is shorter than the jump. To request a
358 fast tracepoint, use the "ftrace" command, with syntax identical to
359 the regular trace command.
361 ** Disconnected tracing
363 It is now possible to detach GDB from the target while it is running
364 a trace experiment, then reconnect later to see how the experiment
365 is going. In addition, a new variable disconnected-tracing lets you
366 tell the target agent whether to continue running a trace if the
367 connection is lost unexpectedly.
371 GDB now has the ability to save the trace buffer into a file, and
372 then use that file as a target, similarly to you can do with
373 corefiles. You can select trace frames, print data that was
374 collected in them, and use tstatus to display the state of the
375 tracing run at the moment that it was saved. To create a trace
376 file, use "tsave <filename>", and to use it, do "target tfile
379 ** Circular trace buffer
381 You can ask the target agent to handle the trace buffer as a
382 circular buffer, discarding the oldest trace frames to make room for
383 newer ones, by setting circular-trace-buffer to on. This feature may
384 not be available for all target agents.
389 The disassemble command, when invoked with two arguments, now requires
390 the arguments to be comma-separated.
393 The info variables command now displays variable definitions. Files
394 which only declare a variable are not shown.
397 The source command is now capable of sourcing Python scripts.
398 This feature is dependent on the debugger being build with Python
401 Related to this enhancement is also the introduction of a new command
402 "set script-extension" (see below).
404 * New commands (for set/show, see "New options" below)
406 record save [<FILENAME>]
407 Save a file (in core file format) containing the process record
408 execution log for replay debugging at a later time.
410 record restore <FILENAME>
411 Restore the process record execution log that was saved at an
412 earlier time, for replay debugging.
414 add-inferior [-copies <N>] [-exec <FILENAME>]
417 clone-inferior [-copies <N>] [ID]
418 Make a new inferior ready to execute the same program another
424 maint info program-spaces
425 List the program spaces loaded into GDB.
427 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
428 show remote interrupt-sequence
429 Allow the user to select one of ^C, a BREAK signal or BREAK-g
430 as the sequence to the remote target in order to interrupt the execution.
431 Ctrl-C is a default. Some system prefers BREAK which is high level of
432 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
433 Magic SysRq g. It is BREAK signal and character 'g'.
435 set remote interrupt-on-connect [on | off]
436 show remote interrupt-on-connect
437 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
438 remote target when gdb connects to it. This is needed when you debug
441 set remotebreak [on | off]
443 Deprecated. Use "set/show remote interrupt-sequence" instead.
445 tvariable $NAME [ = EXP ]
446 Create or modify a trace state variable.
449 List trace state variables and their values.
451 delete tvariable $NAME ...
452 Delete one or more trace state variables.
455 Evaluate the given expressions without collecting anything into the
456 trace buffer. (Valid in tracepoint actions only.)
458 ftrace FN / FILE:LINE / *ADDR
459 Define a fast tracepoint at the given function, line, or address.
461 * New expression syntax
463 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
464 GDB now parses 0b101010 identically with 42.
468 set follow-exec-mode new|same
469 show follow-exec-mode
470 Control whether GDB reuses the same inferior across an exec call or
471 creates a new one. This is useful to be able to restart the old
472 executable after the inferior having done an exec call.
474 set default-collect EXPR, ...
476 Define a list of expressions to be collected at each tracepoint.
477 This is a useful way to ensure essential items are not overlooked,
478 such as registers or a critical global variable.
480 set disconnected-tracing
481 show disconnected-tracing
482 If set to 1, the target is instructed to continue tracing if it
483 loses its connection to GDB. If 0, the target is to stop tracing
486 set circular-trace-buffer
487 show circular-trace-buffer
488 If set to on, the target is instructed to use a circular trace buffer
489 and discard the oldest trace frames instead of stopping the trace due
490 to a full trace buffer. If set to off, the trace stops when the buffer
491 fills up. Some targets may not support this.
493 set script-extension off|soft|strict
494 show script-extension
495 If set to "off", the debugger does not perform any script language
496 recognition, and all sourced files are assumed to be GDB scripts.
497 If set to "soft" (the default), files are sourced according to
498 filename extension, falling back to GDB scripts if the first
500 If set to "strict", files are sourced according to filename extension.
502 set ada trust-PAD-over-XVS on|off
503 show ada trust-PAD-over-XVS
504 If off, activate a workaround against a bug in the debugging information
505 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
506 the GCC sources for more information about the GNAT encoding and
507 PAD types in particular). It is always safe to set this option to
508 off, but this introduces a slight performance penalty. The default
511 * Python API Improvements
513 ** GDB provides the new class gdb.LazyString. This is useful in
514 some pretty-printing cases. The new method gdb.Value.lazy_string
515 provides a simple way to create objects of this type.
517 ** The fields returned by gdb.Type.fields now have an
518 `is_base_class' attribute.
520 ** The new method gdb.Type.range returns the range of an array type.
522 ** The new method gdb.parse_and_eval can be used to parse and
523 evaluate an expression.
528 Define a trace state variable.
531 Get the current value of a trace state variable.
534 Set desired tracing behavior upon disconnection.
537 Set the trace buffer to be linear or circular.
540 Get data about the tracepoints currently in use.
544 Process record now works correctly with hardware watchpoints.
546 Multiple bug fixes have been made to the mips-irix port, making it
547 much more reliable. In particular:
548 - Debugging threaded applications is now possible again. Previously,
549 GDB would hang while starting the program, or while waiting for
550 the program to stop at a breakpoint.
551 - Attaching to a running process no longer hangs.
552 - An error occurring while loading a core file has been fixed.
553 - Changing the value of the PC register now works again. This fixes
554 problems observed when using the "jump" command, or when calling
555 a function from GDB, or even when assigning a new value to $pc.
556 - With the "finish" and "return" commands, the return value for functions
557 returning a small array is now correctly printed.
558 - It is now possible to break on shared library code which gets executed
559 during a shared library init phase (code executed while executing
560 their .init section). Previously, the breakpoint would have no effect.
561 - GDB is now able to backtrace through the signal handler for
562 non-threaded programs.
564 PIE (Position Independent Executable) programs debugging is now supported.
565 This includes debugging execution of PIC (Position Independent Code) shared
566 libraries although for that, it should be possible to run such libraries as an
569 *** Changes in GDB 7.0
571 * GDB now has an interface for JIT compilation. Applications that
572 dynamically generate code can create symbol files in memory and register
573 them with GDB. For users, the feature should work transparently, and
574 for JIT developers, the interface is documented in the GDB manual in the
575 "JIT Compilation Interface" chapter.
577 * Tracepoints may now be conditional. The syntax is as for
578 breakpoints; either an "if" clause appended to the "trace" command,
579 or the "condition" command is available. GDB sends the condition to
580 the target for evaluation using the same bytecode format as is used
581 for tracepoint actions.
583 * The disassemble command now supports: an optional /r modifier, print the
584 raw instructions in hex as well as in symbolic form, and an optional /m
585 modifier to print mixed source+assembly.
587 * Process record and replay
589 In a architecture environment that supports ``process record and
590 replay'', ``process record and replay'' target can record a log of
591 the process execution, and replay it with both forward and reverse
594 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
595 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
596 set execution-direction {forward|reverse}, for targets that support
599 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
600 feature is available with a native GDB running on kernel version
603 * GDB now has support for multi-byte and wide character sets on the
604 target. Strings whose character type is wchar_t, char16_t, or
605 char32_t are now correctly printed. GDB supports wide- and unicode-
606 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
607 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
608 `printf'. This feature requires iconv to work properly; if your
609 system does not have a working iconv, GDB can use GNU libiconv. See
610 the installation instructions for more information.
612 * GDB now supports automatic retrieval of shared library files from
613 remote targets. To use this feature, specify a system root that begins
614 with the `remote:' prefix, either via the `set sysroot' command or via
615 the `--with-sysroot' configure-time option.
617 * "info sharedlibrary" now takes an optional regex of libraries to show,
618 and it now reports if a shared library has no debugging information.
620 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
621 now complete on file names.
623 * When completing in expressions, gdb will attempt to limit
624 completions to allowable structure or union fields, where appropriate.
625 For instance, consider:
627 # struct example { int f1; double f2; };
628 # struct example variable;
631 If the user types TAB at the end of this command line, the available
632 completions will be "f1" and "f2".
634 * Inlined functions are now supported. They show up in backtraces, and
635 the "step", "next", and "finish" commands handle them automatically.
637 * GDB now supports the token-splicing (##) and stringification (#)
638 operators when expanding macros. It also supports variable-arity
641 * GDB now supports inspecting extra signal information, exported by
642 the new $_siginfo convenience variable. The feature is currently
643 implemented on linux ARM, i386 and amd64.
645 * GDB can now display the VFP floating point registers and NEON vector
646 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
647 can provide these registers (requires Linux 2.6.30 or later). Remote
648 and simulator targets may also provide them.
653 Search memory for a sequence of bytes.
656 Turn off `+'/`-' protocol acknowledgments to permit more efficient
657 operation over reliable transport links. Use of this packet is
658 controlled by the `set remote noack-packet' command.
661 Kill the process with the specified process ID. Use this in preference
662 to `k' when multiprocess protocol extensions are supported.
665 Obtains additional operating system information
669 Read or write additional signal information.
671 * Removed remote protocol undocumented extension
673 An undocumented extension to the remote protocol's `S' stop reply
674 packet that permited the stub to pass a process id was removed.
675 Remote servers should use the `T' stop reply packet instead.
677 * GDB now supports multiple function calling conventions according to the
678 DWARF-2 DW_AT_calling_convention function attribute.
680 * The SH target utilizes the aforementioned change to distinguish between gcc
681 and Renesas calling convention. It also adds the new CLI commands
682 `set/show sh calling-convention'.
684 * GDB can now read compressed debug sections, as produced by GNU gold
685 with the --compress-debug-sections=zlib flag.
687 * 64-bit core files are now supported on AIX.
689 * Thread switching is now supported on Tru64.
691 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
692 which will be allocated using malloc later in program execution.
694 * The qXfer:libraries:read remote procotol packet now allows passing a
695 list of section offsets.
697 * On GNU/Linux, GDB can now attach to stopped processes. Several race
698 conditions handling signals delivered during attach or thread creation
699 have also been fixed.
701 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
702 From the user's standpoint, all unqualified instances of True and False
703 are treated as the standard definitions, regardless of context.
705 * GDB now parses C++ symbol and type names more flexibly. For
708 template<typename T> class C { };
711 GDB will now correctly handle all of:
713 ptype C<char const *>
715 ptype C<const char *>
718 * New features in the GDB remote stub, gdbserver
720 - The "--wrapper" command-line argument tells gdbserver to use a
721 wrapper program to launch programs for debugging.
723 - On PowerPC and S/390 targets, it is now possible to use a single
724 gdbserver executable to debug both 32-bit and 64-bit programs.
725 (This requires gdbserver itself to be built as a 64-bit executable.)
727 - gdbserver uses the new noack protocol mode for TCP connections to
728 reduce communications latency, if also supported and enabled in GDB.
730 - Support for the sparc64-linux-gnu target is now included in
733 - The amd64-linux build of gdbserver now supports debugging both
734 32-bit and 64-bit programs.
736 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
737 now support hardware watchpoints, and will use them automatically
742 GDB now has support for scripting using Python. Whether this is
743 available is determined at configure time.
745 New GDB commands can now be written in Python.
747 * Ada tasking support
749 Ada tasks can now be inspected in GDB. The following commands have
753 Print the list of Ada tasks.
755 Print detailed information about task number N.
757 Print the task number of the current task.
759 Switch the context of debugging to task number N.
761 * Support for user-defined prefixed commands. The "define" command can
762 add new commands to existing prefixes, e.g. "target".
764 * Multi-inferior, multi-process debugging.
766 GDB now has generalized support for multi-inferior debugging. See
767 "Debugging Multiple Inferiors" in the manual for more information.
768 Although availability still depends on target support, the command
769 set is more uniform now. The GNU/Linux specific multi-forks support
770 has been migrated to this new framework. This implied some user
771 visible changes; see "New commands" and also "Removed commands"
774 * Target descriptions can now describe the target OS ABI. See the
775 "Target Description Format" section in the user manual for more
778 * Target descriptions can now describe "compatible" architectures
779 to indicate that the target can execute applications for a different
780 architecture in addition to those for the main target architecture.
781 See the "Target Description Format" section in the user manual for
784 * Multi-architecture debugging.
786 GDB now includes general supports for debugging applications on
787 hybrid systems that use more than one single processor architecture
788 at the same time. Each such hybrid architecture still requires
789 specific support to be added. The only hybrid architecture supported
790 in this version of GDB is the Cell Broadband Engine.
792 * GDB now supports integrated debugging of Cell/B.E. applications that
793 use both the PPU and SPU architectures. To enable support for hybrid
794 Cell/B.E. debugging, you need to configure GDB to support both the
795 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
796 --enable-targets configure option.
798 * Non-stop mode debugging.
800 For some targets, GDB now supports an optional mode of operation in
801 which you can examine stopped threads while other threads continue
802 to execute freely. This is referred to as non-stop mode, with the
803 old mode referred to as all-stop mode. See the "Non-Stop Mode"
804 section in the user manual for more information.
806 To be able to support remote non-stop debugging, a remote stub needs
807 to implement the non-stop mode remote protocol extensions, as
808 described in the "Remote Non-Stop" section of the user manual. The
809 GDB remote stub, gdbserver, has been adjusted to support these
810 extensions on linux targets.
812 * New commands (for set/show, see "New options" below)
814 catch syscall [NAME(S) | NUMBER(S)]
815 Catch system calls. Arguments, which should be names of system
816 calls or their numbers, mean catch only those syscalls. Without
817 arguments, every syscall will be caught. When the inferior issues
818 any of the specified syscalls, GDB will stop and announce the system
819 call, both when it is called and when its call returns. This
820 feature is currently available with a native GDB running on the
821 Linux Kernel, under the following architectures: x86, x86_64,
822 PowerPC and PowerPC64.
824 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
826 Search memory for a sequence of bytes.
828 maint set python print-stack
829 maint show python print-stack
830 Show a stack trace when an error is encountered in a Python script.
833 Invoke CODE by passing it to the Python interpreter.
838 These allow macros to be defined, undefined, and listed
842 Show operating system information about processes.
845 List the inferiors currently under GDB's control.
848 Switch focus to inferior number NUM.
851 Detach from inferior number NUM.
854 Kill inferior number NUM.
859 show spu stop-on-load
860 Control whether to stop for new SPE threads during Cell/B.E. debugging.
862 set spu auto-flush-cache
863 show spu auto-flush-cache
864 Control whether to automatically flush the software-managed cache
865 during Cell/B.E. debugging.
867 set sh calling-convention
868 show sh calling-convention
869 Control the calling convention used when calling SH target functions.
873 Control display of timestamps with GDB debugging output.
875 set disassemble-next-line
876 show disassemble-next-line
877 Control display of disassembled source lines or instructions when
880 set remote noack-packet
881 show remote noack-packet
882 Set/show the use of remote protocol QStartNoAckMode packet. See above
883 under "New remote packets."
885 set remote query-attached-packet
886 show remote query-attached-packet
887 Control use of remote protocol `qAttached' (query-attached) packet.
889 set remote read-siginfo-object
890 show remote read-siginfo-object
891 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
894 set remote write-siginfo-object
895 show remote write-siginfo-object
896 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
899 set remote reverse-continue
900 show remote reverse-continue
901 Control use of remote protocol 'bc' (reverse-continue) packet.
903 set remote reverse-step
904 show remote reverse-step
905 Control use of remote protocol 'bs' (reverse-step) packet.
907 set displaced-stepping
908 show displaced-stepping
909 Control displaced stepping mode. Displaced stepping is a way to
910 single-step over breakpoints without removing them from the debuggee.
911 Also known as "out-of-line single-stepping".
915 Control display of debugging info for displaced stepping.
917 maint set internal-error
918 maint show internal-error
919 Control what GDB does when an internal error is detected.
921 maint set internal-warning
922 maint show internal-warning
923 Control what GDB does when an internal warning is detected.
928 Use a wrapper program to launch programs for debugging.
930 set multiple-symbols (all|ask|cancel)
931 show multiple-symbols
932 The value of this variable can be changed to adjust the debugger behavior
933 when an expression or a breakpoint location contains an ambiguous symbol
934 name (an overloaded function name, for instance).
936 set breakpoint always-inserted
937 show breakpoint always-inserted
938 Keep breakpoints always inserted in the target, as opposed to inserting
939 them when resuming the target, and removing them when the target stops.
940 This option can improve debugger performance on slow remote targets.
942 set arm fallback-mode (arm|thumb|auto)
943 show arm fallback-mode
944 set arm force-mode (arm|thumb|auto)
946 These commands control how ARM GDB determines whether instructions
947 are ARM or Thumb. The default for both settings is auto, which uses
948 the current CPSR value for instructions without symbols; previous
949 versions of GDB behaved as if "set arm fallback-mode arm".
951 set disable-randomization
952 show disable-randomization
953 Standalone programs run with the virtual address space randomization enabled
954 by default on some platforms. This option keeps the addresses stable across
955 multiple debugging sessions.
959 Control whether other threads are stopped or not when some thread hits
964 Requests that asynchronous execution is enabled in the target, if available.
965 In this case, it's possible to resume target in the background, and interact
966 with GDB while the target is running. "show target-async" displays the
967 current state of asynchronous execution of the target.
969 set target-wide-charset
970 show target-wide-charset
971 The target-wide-charset is the name of the character set that GDB
972 uses when printing characters whose type is wchar_t.
974 set tcp auto-retry (on|off)
976 set tcp connect-timeout
977 show tcp connect-timeout
978 These commands allow GDB to retry failed TCP connections to a remote stub
979 with a specified timeout period; this is useful if the stub is launched
980 in parallel with GDB but may not be ready to accept connections immediately.
982 set libthread-db-search-path
983 show libthread-db-search-path
984 Control list of directories which GDB will search for appropriate
987 set schedule-multiple (on|off)
988 show schedule-multiple
989 Allow GDB to resume all threads of all processes or only threads of
994 Use more aggressive caching for accesses to the stack. This improves
995 performance of remote debugging (particularly backtraces) without
996 affecting correctness.
998 set interactive-mode (on|off|auto)
999 show interactive-mode
1000 Control whether GDB runs in interactive mode (on) or not (off).
1001 When in interactive mode, GDB waits for the user to answer all
1002 queries. Otherwise, GDB does not wait and assumes the default
1003 answer. When set to auto (the default), GDB determines which
1004 mode to use based on the stdin settings.
1009 For program forks, this is replaced by the new more generic `info
1010 inferiors' command. To list checkpoints, you can still use the
1011 `info checkpoints' command, which was an alias for the `info forks'
1015 Replaced by the new `inferior' command. To switch between
1016 checkpoints, you can still use the `restart' command, which was an
1017 alias for the `fork' command.
1020 This is removed, since some targets don't have a notion of
1021 processes. To switch between processes, you can still use the
1022 `inferior' command using GDB's own inferior number.
1025 For program forks, this is replaced by the new more generic `kill
1026 inferior' command. To delete a checkpoint, you can still use the
1027 `delete checkpoint' command, which was an alias for the `delete
1031 For program forks, this is replaced by the new more generic `detach
1032 inferior' command. To detach a checkpoint, you can still use the
1033 `detach checkpoint' command, which was an alias for the `detach
1036 * New native configurations
1038 x86/x86_64 Darwin i[34567]86-*-darwin*
1040 x86_64 MinGW x86_64-*-mingw*
1044 Lattice Mico32 lm32-*
1045 x86 DICOS i[34567]86-*-dicos*
1046 x86_64 DICOS x86_64-*-dicos*
1049 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1050 (mingw32ce) debugging.
1056 These commands were actually not implemented on any target.
1058 *** Changes in GDB 6.8
1060 * New native configurations
1062 NetBSD/hppa hppa*-*netbsd*
1063 Xtensa GNU/Linux xtensa*-*-linux*
1067 NetBSD/hppa hppa*-*-netbsd*
1068 Xtensa GNU/Lunux xtensa*-*-linux*
1070 * Change in command line behavior -- corefiles vs. process ids.
1072 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1073 attaching to process NUMBER fails, GDB no longer attempts to open a
1074 core file named NUMBER. Attaching to a program using the -c option
1075 is no longer supported. Instead, use the '-p' or '--pid' options.
1077 * GDB can now be built as a native debugger for debugging Windows x86
1078 (mingw32) Portable Executable (PE) programs.
1080 * Pending breakpoints no longer change their number when their address
1083 * GDB now supports breakpoints with multiple locations,
1084 including breakpoints on C++ constructors, inside C++ templates,
1085 and in inlined functions.
1087 * GDB's ability to debug optimized code has been improved. GDB more
1088 accurately identifies function bodies and lexical blocks that occupy
1089 more than one contiguous range of addresses.
1091 * Target descriptions can now describe registers for PowerPC.
1093 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1094 registers on PowerPC targets.
1096 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1097 targets even when the libthread_db library is not available.
1099 * The GDB remote stub, gdbserver, now supports the new file transfer
1100 commands (remote put, remote get, and remote delete).
1102 * The GDB remote stub, gdbserver, now supports run and attach in
1103 extended-remote mode.
1105 * hppa*64*-*-hpux11* target broken
1106 The debugger is unable to start a program and fails with the following
1107 error: "Error trying to get information about dynamic linker".
1108 The gdb-6.7 release is also affected.
1110 * GDB now supports the --enable-targets= configure option to allow
1111 building a single GDB executable that supports multiple remote
1112 target architectures.
1114 * GDB now supports debugging C and C++ programs which use the
1115 Decimal Floating Point extension. In addition, the PowerPC target
1116 now has a set of pseudo-registers to inspect decimal float values
1117 stored in two consecutive float registers.
1119 * The -break-insert MI command can optionally create pending
1122 * Improved support for debugging Ada
1123 Many improvements to the Ada language support have been made. These
1125 - Better support for Ada2005 interface types
1126 - Improved handling of arrays and slices in general
1127 - Better support for Taft-amendment types
1128 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1130 - Improved command completion in Ada
1133 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1138 set print frame-arguments (all|scalars|none)
1139 show print frame-arguments
1140 The value of this variable can be changed to control which argument
1141 values should be printed by the debugger when displaying a frame.
1146 Transfer files to and from a remote target, and delete remote files.
1153 Transfer files to and from a remote target, and delete remote files.
1155 * New remote packets
1162 Open, close, read, write, and delete files on the remote system.
1165 Attach to an existing process on the remote system, in extended-remote
1169 Run a new process on the remote system, in extended-remote mode.
1171 *** Changes in GDB 6.7
1173 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1174 bfd, libiberty and opcodes, as revealed by static analysis donated by
1175 Coverity, Inc. (http://scan.coverity.com).
1177 * When looking up multiply-defined global symbols, GDB will now prefer the
1178 symbol definition in the current shared library if it was built using the
1179 -Bsymbolic linker option.
1181 * When the Text User Interface (TUI) is not configured, GDB will now
1182 recognize the -tui command-line option and print a message that the TUI
1185 * The GDB remote stub, gdbserver, now has lower overhead for high
1186 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1188 * GDB for MIPS targets now autodetects whether a remote target provides
1189 32-bit or 64-bit register values.
1191 * Support for C++ member pointers has been improved.
1193 * GDB now understands XML target descriptions, which specify the
1194 target's overall architecture. GDB can read a description from
1195 a local file or over the remote serial protocol.
1197 * Vectors of single-byte data use a new integer type which is not
1198 automatically displayed as character or string data.
1200 * The /s format now works with the print command. It displays
1201 arrays of single-byte integers and pointers to single-byte integers
1204 * Target descriptions can now describe target-specific registers,
1205 for architectures which have implemented the support (currently
1206 only ARM, M68K, and MIPS).
1208 * GDB and the GDB remote stub, gdbserver, now support the XScale
1211 * The GDB remote stub, gdbserver, has been updated to support
1212 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1213 has been rewritten to use the standard GDB remote protocol.
1215 * GDB can now step into C++ functions which are called through thunks.
1217 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1219 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1220 layout. It also supports a TextSeg= and DataSeg= response when only
1221 segment base addresses (rather than offsets) are available.
1223 * The /i format now outputs any trailing branch delay slot instructions
1224 immediately following the last instruction within the count specified.
1226 * The GDB remote protocol "T" stop reply packet now supports a
1227 "library" response. Combined with the new "qXfer:libraries:read"
1228 packet, this response allows GDB to debug shared libraries on targets
1229 where the operating system manages the list of loaded libraries (e.g.
1230 Windows and SymbianOS).
1232 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1233 (DLLs) on Windows and Windows CE targets.
1235 * GDB now supports a faster verification that a .debug file matches its binary
1236 according to its build-id signature, if the signature is present.
1242 Enable or disable hardware flow control (RTS/CTS) on the serial port
1243 when debugging using remote targets.
1245 set mem inaccessible-by-default
1246 show mem inaccessible-by-default
1247 If the target supplies a memory map, for instance via the remote
1248 protocol's "qXfer:memory-map:read" packet, setting this variable
1249 prevents GDB from accessing memory outside the memory map. This
1250 is useful for targets with memory mapped registers or which react
1251 badly to accesses of unmapped address space.
1253 set breakpoint auto-hw
1254 show breakpoint auto-hw
1255 If the target supplies a memory map, for instance via the remote
1256 protocol's "qXfer:memory-map:read" packet, setting this variable
1257 lets GDB use hardware breakpoints automatically for memory regions
1258 where it can not use software breakpoints. This covers both the
1259 "break" command and internal breakpoints used for other commands
1260 including "next" and "finish".
1263 catch exception unhandled
1264 Stop the program execution when Ada exceptions are raised.
1267 Stop the program execution when an Ada assertion failed.
1271 Set an alternate system root for target files. This is a more
1272 general version of "set solib-absolute-prefix", which is now
1273 an alias to "set sysroot".
1276 Provide extended SPU facility status information. This set of
1277 commands is available only when debugging the Cell/B.E. SPU
1280 * New native configurations
1282 OpenBSD/sh sh*-*openbsd*
1285 unset tdesc filename
1287 Use the specified local file as an XML target description, and do
1288 not query the target for its built-in description.
1292 OpenBSD/sh sh*-*-openbsd*
1293 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1294 Toshiba Media Processor mep-elf
1296 * New remote packets
1299 Ignore the specified signals; pass them directly to the debugged program
1300 without stopping other threads or reporting them to GDB.
1302 qXfer:features:read:
1303 Read an XML target description from the target, which describes its
1308 Read or write contents of an spufs file on the target system. These
1309 packets are available only on the Cell/B.E. SPU architecture.
1311 qXfer:libraries:read:
1312 Report the loaded shared libraries. Combined with new "T" packet
1313 response, this packet allows GDB to debug shared libraries on
1314 targets where the operating system manages the list of loaded
1315 libraries (e.g. Windows and SymbianOS).
1319 Support for these obsolete configurations has been removed.
1327 i[34567]86-*-lynxos*
1328 i[34567]86-*-netware*
1329 i[34567]86-*-sco3.2v5*
1330 i[34567]86-*-sco3.2v4*
1332 i[34567]86-*-sysv4.2*
1335 i[34567]86-*-unixware2*
1336 i[34567]86-*-unixware*
1345 * Other removed features
1352 Various m68k-only ROM monitors.
1359 Various Renesas ROM monitors and debugging interfaces for SH and
1364 Support for a Macraigor serial interface to on-chip debugging.
1365 GDB does not directly support the newer parallel or USB
1370 A debug information format. The predecessor to DWARF 2 and
1371 DWARF 3, which are still supported.
1373 Support for the HP aCC compiler on HP-UX/PA-RISC
1375 SOM-encapsulated symbolic debugging information, automatic
1376 invocation of pxdb, and the aCC custom C++ ABI. This does not
1377 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1378 with aCC can still be debugged on an assembly level.
1380 MIPS ".pdr" sections
1382 A MIPS-specific format used to describe stack frame layout
1383 in debugging information.
1387 GDB could work with an older version of Guile to debug
1388 the interpreter and Scheme programs running in it.
1390 set mips stack-arg-size
1391 set mips saved-gpreg-size
1393 Use "set mips abi" to control parameter passing for MIPS.
1395 *** Changes in GDB 6.6
1400 Cell Broadband Engine SPU spu-elf
1402 * GDB can now be configured as a cross-debugger targeting native Windows
1403 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1404 running on a Windows system over TCP/IP to debug Windows programs.
1406 * The GDB remote stub, gdbserver, has been updated to support Windows and
1407 Cygwin debugging. Both single-threaded and multi-threaded programs are
1410 * The "set trust-readonly-sections" command works again. This command was
1411 broken in GDB 6.3, 6.4, and 6.5.
1413 * The "load" command now supports writing to flash memory, if the remote
1414 stub provides the required support.
1416 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1417 longer requires symbolic debug information (e.g. DWARF-2).
1422 unset substitute-path
1423 show substitute-path
1424 Manage a list of substitution rules that GDB uses to rewrite the name
1425 of the directories where the sources are located. This can be useful
1426 for instance when the sources were moved to a different location
1427 between compilation and debugging.
1431 Print each CLI command as it is executed. Each command is prefixed with
1432 a number of `+' symbols representing the nesting depth.
1433 The source command now has a `-v' option to enable the same feature.
1437 The ARM Demon monitor support (RDP protocol, "target rdp").
1439 Kernel Object Display, an embedded debugging feature which only worked with
1440 an obsolete version of Cisco IOS.
1442 The 'set download-write-size' and 'show download-write-size' commands.
1444 * New remote packets
1447 Tell a stub about GDB client features, and request remote target features.
1448 The first feature implemented is PacketSize, which allows the target to
1449 specify the size of packets it can handle - to minimize the number of
1450 packets required and improve performance when connected to a remote
1454 Fetch an OS auxilliary vector from the remote stub. This packet is a
1455 more efficient replacement for qPart:auxv:read.
1457 qXfer:memory-map:read:
1458 Fetch a memory map from the remote stub, including information about
1459 RAM, ROM, and flash memory devices.
1464 Erase and program a flash memory device.
1466 * Removed remote packets
1469 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1470 used it, and only gdbserver implemented it.
1472 *** Changes in GDB 6.5
1476 Renesas M32C/M16C m32c-elf
1478 Morpho Technologies ms1 ms1-elf
1482 init-if-undefined Initialize a convenience variable, but
1483 only if it doesn't already have a value.
1485 The following commands are presently only implemented for native GNU/Linux:
1487 checkpoint Save a snapshot of the program state.
1489 restart <n> Return the program state to a
1490 previously saved state.
1492 info checkpoints List currently saved checkpoints.
1494 delete-checkpoint <n> Delete a previously saved checkpoint.
1496 set|show detach-on-fork Tell gdb whether to detach from a newly
1497 forked process, or to keep debugging it.
1499 info forks List forks of the user program that
1500 are available to be debugged.
1502 fork <n> Switch to debugging one of several
1503 forks of the user program that are
1504 available to be debugged.
1506 delete-fork <n> Delete a fork from the list of forks
1507 that are available to be debugged (and
1508 kill the forked process).
1510 detach-fork <n> Delete a fork from the list of forks
1511 that are available to be debugged (and
1512 allow the process to continue).
1516 Morpho Technologies ms2 ms1-elf
1518 * Improved Windows host support
1520 GDB now builds as a cross debugger hosted on i686-mingw32, including
1521 native console support, and remote communications using either
1522 network sockets or serial ports.
1524 * Improved Modula-2 language support
1526 GDB can now print most types in the Modula-2 syntax. This includes:
1527 basic types, set types, record types, enumerated types, range types,
1528 pointer types and ARRAY types. Procedure var parameters are correctly
1529 printed and hexadecimal addresses and character constants are also
1530 written in the Modula-2 syntax. Best results can be obtained by using
1531 GNU Modula-2 together with the -gdwarf-2 command line option.
1535 The ARM rdi-share module.
1537 The Netware NLM debug server.
1539 *** Changes in GDB 6.4
1541 * New native configurations
1543 OpenBSD/arm arm*-*-openbsd*
1544 OpenBSD/mips64 mips64-*-openbsd*
1548 Morpho Technologies ms1 ms1-elf
1550 * New command line options
1552 --batch-silent As for --batch, but totally silent.
1553 --return-child-result The debugger will exist with the same value
1554 the child (debugged) program exited with.
1555 --eval-command COMMAND, -ex COMMAND
1556 Execute a single GDB CLI command. This may be
1557 specified multiple times and in conjunction
1558 with the --command (-x) option.
1560 * Deprecated commands removed
1562 The following commands, that were deprecated in 2000, have been
1566 set|show arm disassembly-flavor set|show arm disassembler
1567 othernames set arm disassembler
1568 set|show remotedebug set|show debug remote
1569 set|show archdebug set|show debug arch
1570 set|show eventdebug set|show debug event
1573 * New BSD user-level threads support
1575 It is now possible to debug programs using the user-level threads
1576 library on OpenBSD and FreeBSD. Currently supported (target)
1579 FreeBSD/amd64 x86_64-*-freebsd*
1580 FreeBSD/i386 i386-*-freebsd*
1581 OpenBSD/i386 i386-*-openbsd*
1583 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1584 are not yet supported.
1586 * New support for Matsushita MN10300 w/sim added
1587 (Work in progress). mn10300-elf.
1589 * REMOVED configurations and files
1591 VxWorks and the XDR protocol *-*-vxworks
1592 Motorola MCORE mcore-*-*
1593 National Semiconductor NS32000 ns32k-*-*
1595 * New "set print array-indexes" command
1597 After turning this setting "on", GDB prints the index of each element
1598 when displaying arrays. The default is "off" to preserve the previous
1601 * VAX floating point support
1603 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1605 * User-defined command support
1607 In addition to using $arg0..$arg9 for argument passing, it is now possible
1608 to use $argc to determine now many arguments have been passed. See the
1609 section on user-defined commands in the user manual for more information.
1611 *** Changes in GDB 6.3:
1613 * New command line option
1615 GDB now accepts -l followed by a number to set the timeout for remote
1618 * GDB works with GCC -feliminate-dwarf2-dups
1620 GDB now supports a more compact representation of DWARF-2 debug
1621 information using DW_FORM_ref_addr references. These are produced
1622 by GCC with the option -feliminate-dwarf2-dups and also by some
1623 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1624 to use -feliminate-dwarf2-dups.
1626 * Internationalization
1628 When supported by the host system, GDB will be built with
1629 internationalization (libintl). The task of marking up the sources is
1630 continued, we're looking forward to our first translation.
1634 Initial support for debugging programs compiled with the GNAT
1635 implementation of the Ada programming language has been integrated
1636 into GDB. In this release, support is limited to expression evaluation.
1638 * New native configurations
1640 GNU/Linux/m32r m32r-*-linux-gnu
1644 GDB's remote protocol now includes support for the 'p' packet. This
1645 packet is used to fetch individual registers from a remote inferior.
1647 * END-OF-LIFE registers[] compatibility module
1649 GDB's internal register infrastructure has been completely rewritten.
1650 The new infrastructure making possible the implementation of key new
1651 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1654 GDB 6.3 will be the last release to include the the registers[]
1655 compatibility module that allowed out-of-date configurations to
1656 continue to work. This change directly impacts the following
1666 powerpc bdm protocol
1668 Unless there is activity to revive these configurations, they will be
1669 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1671 * OBSOLETE configurations and files
1673 Configurations that have been declared obsolete in this release have
1674 been commented out. Unless there is activity to revive these
1675 configurations, the next release of GDB will have their sources
1676 permanently REMOVED.
1685 *** Changes in GDB 6.2.1:
1687 * MIPS `break main; run' gave an heuristic-fence-post warning
1689 When attempting to run even a simple program, a warning about
1690 heuristic-fence-post being hit would be reported. This problem has
1693 * MIPS IRIX 'long double' crashed GDB
1695 When examining a long double variable, GDB would get a segmentation
1696 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1697 IRIX long double values).
1701 A bug in the VAX stack code was causing problems with the "next"
1702 command. This problem has been fixed.
1704 *** Changes in GDB 6.2:
1706 * Fix for ``many threads''
1708 On GNU/Linux systems that use the NPTL threads library, a program
1709 rapidly creating and deleting threads would confuse GDB leading to the
1712 ptrace: No such process.
1713 thread_db_get_info: cannot get thread info: generic error
1715 This problem has been fixed.
1717 * "-async" and "-noasync" options removed.
1719 Support for the broken "-noasync" option has been removed (it caused
1722 * New ``start'' command.
1724 This command runs the program until the begining of the main procedure.
1726 * New BSD Kernel Data Access Library (libkvm) interface
1728 Using ``target kvm'' it is now possible to debug kernel core dumps and
1729 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1730 platforms. Currently supported (native-only) configurations are:
1732 FreeBSD/amd64 x86_64-*-freebsd*
1733 FreeBSD/i386 i?86-*-freebsd*
1734 NetBSD/i386 i?86-*-netbsd*
1735 NetBSD/m68k m68*-*-netbsd*
1736 NetBSD/sparc sparc-*-netbsd*
1737 OpenBSD/amd64 x86_64-*-openbsd*
1738 OpenBSD/i386 i?86-*-openbsd*
1739 OpenBSD/m68k m68*-openbsd*
1740 OpenBSD/sparc sparc-*-openbsd*
1742 * Signal trampoline code overhauled
1744 Many generic problems with GDB's signal handling code have been fixed.
1745 These include: backtraces through non-contiguous stacks; recognition
1746 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1747 call; backtrace through a signal trampoline; step into and out of
1748 signal handlers; and single-stepping in the signal trampoline.
1750 Please note that kernel bugs are a limiting factor here. These
1751 features have been shown to work on an s390 GNU/Linux system that
1752 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1754 * Cygwin support for DWARF 2 added.
1756 * New native configurations
1758 GNU/Linux/hppa hppa*-*-linux*
1759 OpenBSD/hppa hppa*-*-openbsd*
1760 OpenBSD/m68k m68*-*-openbsd*
1761 OpenBSD/m88k m88*-*-openbsd*
1762 OpenBSD/powerpc powerpc-*-openbsd*
1763 NetBSD/vax vax-*-netbsd*
1764 OpenBSD/vax vax-*-openbsd*
1766 * END-OF-LIFE frame compatibility module
1768 GDB's internal frame infrastructure has been completely rewritten.
1769 The new infrastructure making it possible to support key new features
1770 including DWARF 2 Call Frame Information. To aid in the task of
1771 migrating old configurations to this new infrastructure, a
1772 compatibility module, that allowed old configurations to continue to
1773 work, was also included.
1775 GDB 6.2 will be the last release to include this frame compatibility
1776 module. This change directly impacts the following configurations:
1786 Unless there is activity to revive these configurations, they will be
1787 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1789 * REMOVED configurations and files
1791 Sun 3, running SunOS 3 m68*-*-sunos3*
1792 Sun 3, running SunOS 4 m68*-*-sunos4*
1793 Sun 2, running SunOS 3 m68000-*-sunos3*
1794 Sun 2, running SunOS 4 m68000-*-sunos4*
1795 Motorola 680x0 running LynxOS m68*-*-lynxos*
1796 AT&T 3b1/Unix pc m68*-att-*
1797 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1798 decstation mips-dec-* mips-little-*
1799 riscos mips-*-riscos* mips-*-sysv*
1800 sonymips mips-sony-*
1801 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1803 *** Changes in GDB 6.1.1:
1805 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1807 The TUI (Text-mode User Interface) is now built as part of a default
1808 GDB configuration. It is enabled by either selecting the TUI with the
1809 command line option "-i=tui" or by running the separate "gdbtui"
1810 program. For more information on the TUI, see the manual "Debugging
1813 * Pending breakpoint support (also included in GDB 6.1)
1815 Support has been added to allow you to specify breakpoints in shared
1816 libraries that have not yet been loaded. If a breakpoint location
1817 cannot be found, and the "breakpoint pending" option is set to auto,
1818 GDB queries you if you wish to make the breakpoint pending on a future
1819 shared-library load. If and when GDB resolves the breakpoint symbol,
1820 the pending breakpoint is removed as one or more regular breakpoints
1823 Pending breakpoints are very useful for GCJ Java debugging.
1825 * Fixed ISO-C build problems
1827 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1828 non ISO-C code that stopped them being built using a more strict ISO-C
1829 compiler (e.g., IBM's C compiler).
1831 * Fixed build problem on IRIX 5
1833 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1834 wasn't able to compile compile on an IRIX 5 system.
1836 * Added execute permission to gdb/gdbserver/configure
1838 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1839 permission. This bug would cause configure to fail on a number of
1840 systems (Solaris, IRIX). Ref: server/519.
1842 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1844 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1845 has been updated to use constant array sizes.
1847 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1849 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1850 its generated DWARF Call Frame Info. This encoding was causing GDB to
1851 panic, that panic has been fixed. Ref: gdb/1628.
1853 * Fixed a problem when examining parameters in shared library code.
1855 When examining parameters in optimized shared library code generated
1856 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1857 not available''. GDB now correctly displays the variable's value.
1859 *** Changes in GDB 6.1:
1861 * Removed --with-mmalloc
1863 Support for the mmalloc memory manager has been removed, as it
1864 conflicted with the internal gdb byte cache.
1866 * Changes in AMD64 configurations
1868 The AMD64 target now includes the %cs and %ss registers. As a result
1869 the AMD64 remote protocol has changed; this affects the floating-point
1870 and SSE registers. If you rely on those registers for your debugging,
1871 you should upgrade gdbserver on the remote side.
1873 * Revised SPARC target
1875 The SPARC target has been completely revised, incorporating the
1876 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1877 support for LynxOS and SunOS 4 has been dropped. Calling functions
1878 from within GDB on operating systems with a non-executable stack
1879 (Solaris, OpenBSD) now works.
1883 GDB has a new C++ demangler which does a better job on the mangled
1884 names generated by current versions of g++. It also runs faster, so
1885 with this and other changes gdb should now start faster on large C++
1888 * DWARF 2 Location Expressions
1890 GDB support for location expressions has been extended to support function
1891 arguments and frame bases. Older versions of GDB could crash when they
1894 * C++ nested types and namespaces
1896 GDB's support for nested types and namespaces in C++ has been
1897 improved, especially if you use the DWARF 2 debugging format. (This
1898 is the default for recent versions of GCC on most platforms.)
1899 Specifically, if you have a class "Inner" defined within a class or
1900 namespace "Outer", then GDB realizes that the class's name is
1901 "Outer::Inner", not simply "Inner". This should greatly reduce the
1902 frequency of complaints about not finding RTTI symbols. In addition,
1903 if you are stopped at inside of a function defined within a namespace,
1904 GDB modifies its name lookup accordingly.
1906 * New native configurations
1908 NetBSD/amd64 x86_64-*-netbsd*
1909 OpenBSD/amd64 x86_64-*-openbsd*
1910 OpenBSD/alpha alpha*-*-openbsd*
1911 OpenBSD/sparc sparc-*-openbsd*
1912 OpenBSD/sparc64 sparc64-*-openbsd*
1914 * New debugging protocols
1916 M32R with SDI protocol m32r-*-elf*
1918 * "set prompt-escape-char" command deleted.
1920 The command "set prompt-escape-char" has been deleted. This command,
1921 and its very obscure effet on GDB's prompt, was never documented,
1922 tested, nor mentioned in the NEWS file.
1924 * OBSOLETE configurations and files
1926 Configurations that have been declared obsolete in this release have
1927 been commented out. Unless there is activity to revive these
1928 configurations, the next release of GDB will have their sources
1929 permanently REMOVED.
1931 Sun 3, running SunOS 3 m68*-*-sunos3*
1932 Sun 3, running SunOS 4 m68*-*-sunos4*
1933 Sun 2, running SunOS 3 m68000-*-sunos3*
1934 Sun 2, running SunOS 4 m68000-*-sunos4*
1935 Motorola 680x0 running LynxOS m68*-*-lynxos*
1936 AT&T 3b1/Unix pc m68*-att-*
1937 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1938 decstation mips-dec-* mips-little-*
1939 riscos mips-*-riscos* mips-*-sysv*
1940 sonymips mips-sony-*
1941 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1943 * REMOVED configurations and files
1945 SGI Irix-4.x mips-sgi-irix4 or iris4
1946 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1947 Z8000 simulator z8k-zilog-none or z8ksim
1948 Matsushita MN10200 w/simulator mn10200-*-*
1949 H8/500 simulator h8500-hitachi-hms or h8500hms
1950 HP/PA running BSD hppa*-*-bsd*
1951 HP/PA running OSF/1 hppa*-*-osf*
1952 HP/PA Pro target hppa*-*-pro*
1953 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1954 386BSD i[3456]86-*-bsd*
1955 Sequent family i[3456]86-sequent-sysv4*
1956 i[3456]86-sequent-sysv*
1957 i[3456]86-sequent-bsd*
1958 SPARC running LynxOS sparc-*-lynxos*
1959 SPARC running SunOS 4 sparc-*-sunos4*
1960 Tsqware Sparclet sparclet-*-*
1961 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1963 *** Changes in GDB 6.0:
1967 Support for debugging the Objective-C programming language has been
1968 integrated into GDB.
1970 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1972 DWARF 2's Call Frame Information makes available compiler generated
1973 information that more exactly describes the program's run-time stack.
1974 By using this information, GDB is able to provide more robust stack
1977 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1978 have been updated to use a new backtrace mechanism which includes
1979 DWARF 2 CFI support.
1983 GDB's remote protocol has been extended to include support for hosted
1984 file I/O (where the remote target uses GDB's file system). See GDB's
1985 remote protocol documentation for details.
1987 * All targets using the new architecture framework.
1989 All of GDB's targets have been updated to use the new internal
1990 architecture framework. The way is now open for future GDB releases
1991 to include cross-architecture native debugging support (i386 on amd64,
1994 * GNU/Linux's Thread Local Storage (TLS)
1996 GDB now includes support for for the GNU/Linux implementation of
1997 per-thread variables.
1999 * GNU/Linux's Native POSIX Thread Library (NPTL)
2001 GDB's thread code has been updated to work with either the new
2002 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2004 * Separate debug info.
2006 GDB, in conjunction with BINUTILS, now supports a mechanism for
2007 automatically loading debug information from a separate file. Instead
2008 of shipping full debug and non-debug versions of system libraries,
2009 system integrators can now instead ship just the stripped libraries
2010 and optional debug files.
2012 * DWARF 2 Location Expressions
2014 DWARF 2 Location Expressions allow the compiler to more completely
2015 describe the location of variables (even in optimized code) to the
2018 GDB now includes preliminary support for location expressions (support
2019 for DW_OP_piece is still missing).
2023 A number of long standing bugs that caused GDB to die while starting a
2024 Java application have been fixed. GDB's Java support is now
2025 considered "useable".
2027 * GNU/Linux support for fork, vfork, and exec.
2029 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2030 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2033 * GDB supports logging output to a file
2035 There are two new commands, "set logging" and "show logging", which can be
2036 used to capture GDB's output to a file.
2038 * The meaning of "detach" has changed for gdbserver
2040 The "detach" command will now resume the application, as documented. To
2041 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2044 * d10v, m68hc11 `regs' command deprecated
2046 The `info registers' command has been updated so that it displays the
2047 registers using a format identical to the old `regs' command.
2051 A new command, "maint set profile on/off", has been added. This command can
2052 be used to enable or disable profiling while running GDB, to profile a
2053 session or a set of commands. In addition there is a new configure switch,
2054 "--enable-profiling", which will cause GDB to be compiled with profiling
2055 data, for more informative profiling results.
2057 * Default MI syntax changed to "mi2".
2059 The default MI (machine interface) syntax, enabled by the command line
2060 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2061 "mi1", can be enabled by specifying the option "-i=mi1".
2063 Support for the original "mi0" syntax (included in GDB 5.0) has been
2066 Fix for gdb/192: removed extraneous space when displaying frame level.
2067 Fix for gdb/672: update changelist is now output in mi list format.
2068 Fix for gdb/702: a -var-assign that updates the value now shows up
2069 in a subsequent -var-update.
2071 * New native configurations.
2073 FreeBSD/amd64 x86_64-*-freebsd*
2075 * Multi-arched targets.
2077 HP/PA HPUX11 hppa*-*-hpux*
2078 Renesas M32R/D w/simulator m32r-*-elf*
2080 * OBSOLETE configurations and files
2082 Configurations that have been declared obsolete in this release have
2083 been commented out. Unless there is activity to revive these
2084 configurations, the next release of GDB will have their sources
2085 permanently REMOVED.
2087 Z8000 simulator z8k-zilog-none or z8ksim
2088 Matsushita MN10200 w/simulator mn10200-*-*
2089 H8/500 simulator h8500-hitachi-hms or h8500hms
2090 HP/PA running BSD hppa*-*-bsd*
2091 HP/PA running OSF/1 hppa*-*-osf*
2092 HP/PA Pro target hppa*-*-pro*
2093 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2094 Sequent family i[3456]86-sequent-sysv4*
2095 i[3456]86-sequent-sysv*
2096 i[3456]86-sequent-bsd*
2097 Tsqware Sparclet sparclet-*-*
2098 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2100 * REMOVED configurations and files
2103 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2104 IBM AIX PS/2 i[3456]86-*-aix
2105 i386 running Mach 3.0 i[3456]86-*-mach3*
2106 i386 running Mach i[3456]86-*-mach*
2107 i386 running OSF/1 i[3456]86-*osf1mk*
2108 HP/Apollo 68k Family m68*-apollo*-sysv*,
2110 m68*-hp-bsd*, m68*-hp-hpux*
2111 Argonaut Risc Chip (ARC) arc-*-*
2112 Mitsubishi D30V d30v-*-*
2113 Fujitsu FR30 fr30-*-elf*
2114 OS/9000 i[34]86-*-os9k
2115 I960 with MON960 i960-*-coff
2117 * MIPS $fp behavior changed
2119 The convenience variable $fp, for the MIPS, now consistently returns
2120 the address of the current frame's base. Previously, depending on the
2121 context, $fp could refer to either $sp or the current frame's base
2122 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2123 The GNU Source-Level Debugger''.
2125 *** Changes in GDB 5.3:
2127 * GNU/Linux shared library multi-threaded performance improved.
2129 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2130 `/proc', in preference to `ptrace' for memory reads. This may result
2131 in an improvement in the start-up time of multi-threaded, shared
2132 library applications when run under GDB. One GDB user writes: ``loads
2133 shared libs like mad''.
2135 * ``gdbserver'' now supports multi-threaded applications on some targets
2137 Support for debugging multi-threaded applications which use
2138 the GNU/Linux LinuxThreads package has been added for
2139 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2140 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2142 * GDB now supports C/C++ preprocessor macros.
2144 GDB now expands preprocessor macro invocations in C/C++ expressions,
2145 and provides various commands for showing macro definitions and how
2148 The new command `macro expand EXPRESSION' expands any macro
2149 invocations in expression, and shows the result.
2151 The new command `show macro MACRO-NAME' shows the definition of the
2152 macro named MACRO-NAME, and where it was defined.
2154 Most compilers don't include information about macros in the debugging
2155 information by default. In GCC 3.1, for example, you need to compile
2156 your program with the options `-gdwarf-2 -g3'. If the macro
2157 information is present in the executable, GDB will read it.
2159 * Multi-arched targets.
2161 DEC Alpha (partial) alpha*-*-*
2162 DEC VAX (partial) vax-*-*
2164 National Semiconductor NS32000 (partial) ns32k-*-*
2165 Motorola 68000 (partial) m68k-*-*
2166 Motorola MCORE mcore-*-*
2170 Fujitsu FRV architecture added by Red Hat frv*-*-*
2173 * New native configurations
2175 Alpha NetBSD alpha*-*-netbsd*
2176 SH NetBSD sh*-*-netbsdelf*
2177 MIPS NetBSD mips*-*-netbsd*
2178 UltraSPARC NetBSD sparc64-*-netbsd*
2180 * OBSOLETE configurations and files
2182 Configurations that have been declared obsolete in this release have
2183 been commented out. Unless there is activity to revive these
2184 configurations, the next release of GDB will have their sources
2185 permanently REMOVED.
2187 Mitsubishi D30V d30v-*-*
2188 OS/9000 i[34]86-*-os9k
2189 IBM AIX PS/2 i[3456]86-*-aix
2190 Fujitsu FR30 fr30-*-elf*
2191 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2192 Argonaut Risc Chip (ARC) arc-*-*
2193 i386 running Mach 3.0 i[3456]86-*-mach3*
2194 i386 running Mach i[3456]86-*-mach*
2195 i386 running OSF/1 i[3456]86-*osf1mk*
2196 HP/Apollo 68k Family m68*-apollo*-sysv*,
2198 m68*-hp-bsd*, m68*-hp-hpux*
2199 I960 with MON960 i960-*-coff
2201 * OBSOLETE languages
2203 CHILL, a Pascal like language used by telecommunications companies.
2205 * REMOVED configurations and files
2207 AMD 29k family via UDI a29k-amd-udi, udi29k
2208 A29K VxWorks a29k-*-vxworks
2209 AMD 29000 embedded, using EBMON a29k-none-none
2210 AMD 29000 embedded with COFF a29k-none-coff
2211 AMD 29000 embedded with a.out a29k-none-aout
2213 testsuite/gdb.hp/gdb.threads-hp/ directory
2215 * New command "set max-user-call-depth <nnn>"
2217 This command allows the user to limit the call depth of user-defined
2218 commands. The default is 1024.
2220 * Changes in FreeBSD/i386 native debugging.
2222 Support for the "generate-core-file" has been added.
2224 * New commands "dump", "append", and "restore".
2226 These commands allow data to be copied from target memory
2227 to a bfd-format or binary file (dump and append), and back
2228 from a file into memory (restore).
2230 * Improved "next/step" support on multi-processor Alpha Tru64.
2232 The previous single-step mechanism could cause unpredictable problems,
2233 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2234 of a software single-step mechanism prevents this.
2236 *** Changes in GDB 5.2.1:
2244 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2245 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2246 Fix, by Joel Brobecker imported from mainline.
2248 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2249 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2250 Fix, by Fred Fish, imported from mainline.
2252 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2253 Surprisingly enough, it works now.
2254 By Michal Ludvig, imported from mainline.
2256 i386 hardware watchpoint support:
2257 avoid misses on second run for some targets.
2258 By Pierre Muller, imported from mainline.
2260 *** Changes in GDB 5.2:
2262 * New command "set trust-readonly-sections on[off]".
2264 This command is a hint that tells gdb that read-only sections
2265 really are read-only (ie. that their contents will not change).
2266 In this mode, gdb will go to the object file rather than the
2267 target to read memory from read-only sections (such as ".text").
2268 This can be a significant performance improvement on some
2269 (notably embedded) targets.
2271 * New command "generate-core-file" (or "gcore").
2273 This new gdb command allows the user to drop a core file of the child
2274 process state at any time. So far it's been implemented only for
2275 GNU/Linux and Solaris, but should be relatively easily ported to other
2276 hosts. Argument is core file name (defaults to core.<pid>).
2278 * New command line option
2280 GDB now accepts --pid or -p followed by a process id.
2282 * Change in command line behavior -- corefiles vs. process ids.
2284 There is a subtle behavior in the way in which GDB handles
2285 command line arguments. The first non-flag argument is always
2286 a program to debug, but the second non-flag argument may either
2287 be a corefile or a process id. Previously, GDB would attempt to
2288 open the second argument as a corefile, and if that failed, would
2289 issue a superfluous error message and then attempt to attach it as
2290 a process. Now, if the second argument begins with a non-digit,
2291 it will be treated as a corefile. If it begins with a digit,
2292 GDB will attempt to attach it as a process, and if no such process
2293 is found, will then attempt to open it as a corefile.
2295 * Changes in ARM configurations.
2297 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2298 configuration is fully multi-arch.
2300 * New native configurations
2302 ARM NetBSD arm*-*-netbsd*
2303 x86 OpenBSD i[3456]86-*-openbsd*
2304 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2305 Sparc64 running FreeBSD sparc64-*-freebsd*
2309 Sanyo XStormy16 xstormy16-elf
2311 * OBSOLETE configurations and files
2313 Configurations that have been declared obsolete in this release have
2314 been commented out. Unless there is activity to revive these
2315 configurations, the next release of GDB will have their sources
2316 permanently REMOVED.
2318 AMD 29k family via UDI a29k-amd-udi, udi29k
2319 A29K VxWorks a29k-*-vxworks
2320 AMD 29000 embedded, using EBMON a29k-none-none
2321 AMD 29000 embedded with COFF a29k-none-coff
2322 AMD 29000 embedded with a.out a29k-none-aout
2324 testsuite/gdb.hp/gdb.threads-hp/ directory
2326 * REMOVED configurations and files
2328 TI TMS320C80 tic80-*-*
2330 PowerPC Solaris powerpcle-*-solaris*
2331 PowerPC Windows NT powerpcle-*-cygwin32
2332 PowerPC Netware powerpc-*-netware*
2333 Harris/CXUX m88k m88*-harris-cxux*
2334 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2335 ns32k-utek-sysv* ns32k-utek-*
2336 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2337 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2338 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2339 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2340 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2342 * Changes to command line processing
2344 The new `--args' feature can be used to specify command-line arguments
2345 for the inferior from gdb's command line.
2347 * Changes to key bindings
2349 There is a new `operate-and-get-next' function bound to `C-o'.
2351 *** Changes in GDB 5.1.1
2353 Fix compile problem on DJGPP.
2355 Fix a problem with floating-point registers on the i386 being
2358 Fix to stop GDB crashing on .debug_str debug info.
2360 Numerous documentation fixes.
2362 Numerous testsuite fixes.
2364 *** Changes in GDB 5.1:
2366 * New native configurations
2368 Alpha FreeBSD alpha*-*-freebsd*
2369 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2370 MIPS GNU/Linux mips*-*-linux*
2371 MIPS SGI Irix 6.x mips*-sgi-irix6*
2372 ia64 AIX ia64-*-aix*
2373 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2377 Motorola 68HC11 and 68HC12 m68hc11-elf
2379 UltraSparc running GNU/Linux sparc64-*-linux*
2381 * OBSOLETE configurations and files
2383 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2384 Harris/CXUX m88k m88*-harris-cxux*
2385 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2386 ns32k-utek-sysv* ns32k-utek-*
2387 TI TMS320C80 tic80-*-*
2389 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2390 PowerPC Solaris powerpcle-*-solaris*
2391 PowerPC Windows NT powerpcle-*-cygwin32
2392 PowerPC Netware powerpc-*-netware*
2393 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2394 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2395 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2396 Apple Macintosh (MPW) host N/A
2398 stuff.c (Program to stuff files into a specially prepared space in kdb)
2399 kdb-start.c (Main loop for the standalone kernel debugger)
2401 Configurations that have been declared obsolete in this release have
2402 been commented out. Unless there is activity to revive these
2403 configurations, the next release of GDB will have their sources
2404 permanently REMOVED.
2406 * REMOVED configurations and files
2408 Altos 3068 m68*-altos-*
2409 Convex c1-*-*, c2-*-*
2411 ARM RISCix arm-*-* (as host)
2415 * GDB has been converted to ISO C.
2417 GDB's source code has been converted to ISO C. In particular, the
2418 sources are fully protoized, and rely on standard headers being
2423 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2425 * The MI enabled by default.
2427 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2428 revised and enabled by default. Packages which use GDB as a debugging
2429 engine behind a UI or another front end are encouraged to switch to
2430 using the GDB/MI interface, instead of the old annotations interface
2431 which is now deprecated.
2433 * Support for debugging Pascal programs.
2435 GDB now includes support for debugging Pascal programs. The following
2436 main features are supported:
2438 - Pascal-specific data types such as sets;
2440 - automatic recognition of Pascal sources based on file-name
2443 - Pascal-style display of data types, variables, and functions;
2445 - a Pascal expression parser.
2447 However, some important features are not yet supported.
2449 - Pascal string operations are not supported at all;
2451 - there are some problems with boolean types;
2453 - Pascal type hexadecimal constants are not supported
2454 because they conflict with the internal variables format;
2456 - support for Pascal objects and classes is not full yet;
2458 - unlike Pascal, GDB is case-sensitive for symbol names.
2460 * Changes in completion.
2462 Commands such as `shell', `run' and `set args', which pass arguments
2463 to inferior programs, now complete on file names, similar to what
2464 users expect at the shell prompt.
2466 Commands which accept locations, such as `disassemble', `print',
2467 `breakpoint', `until', etc. now complete on filenames as well as
2468 program symbols. Thus, if you type "break foob TAB", and the source
2469 files linked into the programs include `foobar.c', that file name will
2470 be one of the candidates for completion. However, file names are not
2471 considered for completion after you typed a colon that delimits a file
2472 name from a name of a function in that file, as in "break foo.c:bar".
2474 `set demangle-style' completes on available demangling styles.
2476 * New platform-independent commands:
2478 It is now possible to define a post-hook for a command as well as a
2479 hook that runs before the command. For more details, see the
2480 documentation of `hookpost' in the GDB manual.
2482 * Changes in GNU/Linux native debugging.
2484 Support for debugging multi-threaded programs has been completely
2485 revised for all platforms except m68k and sparc. You can now debug as
2486 many threads as your system allows you to have.
2488 Attach/detach is supported for multi-threaded programs.
2490 Support for SSE registers was added for x86. This doesn't work for
2491 multi-threaded programs though.
2493 * Changes in MIPS configurations.
2495 Multi-arch support is enabled for all MIPS configurations.
2497 GDB can now be built as native debugger on SGI Irix 6.x systems for
2498 debugging n32 executables. (Debugging 64-bit executables is not yet
2501 * Unified support for hardware watchpoints in all x86 configurations.
2503 Most (if not all) native x86 configurations support hardware-assisted
2504 breakpoints and watchpoints in a unified manner. This support
2505 implements debug register sharing between watchpoints, which allows to
2506 put a virtually infinite number of watchpoints on the same address,
2507 and also supports watching regions up to 16 bytes with several debug
2510 The new maintenance command `maintenance show-debug-regs' toggles
2511 debugging print-outs in functions that insert, remove, and test
2512 watchpoints and hardware breakpoints.
2514 * Changes in the DJGPP native configuration.
2516 New command ``info dos sysinfo'' displays assorted information about
2517 the CPU, OS, memory, and DPMI server.
2519 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2520 display information about segment descriptors stored in GDT, LDT, and
2523 New commands ``info dos pde'' and ``info dos pte'' display entries
2524 from Page Directory and Page Tables (for now works with CWSDPMI only).
2525 New command ``info dos address-pte'' displays the Page Table entry for
2526 a given linear address.
2528 GDB can now pass command lines longer than 126 characters to the
2529 program being debugged (requires an update to the libdbg.a library
2530 which is part of the DJGPP development kit).
2532 DWARF2 debug info is now supported.
2534 It is now possible to `step' and `next' through calls to `longjmp'.
2536 * Changes in documentation.
2538 All GDB documentation was converted to GFDL, the GNU Free
2539 Documentation License.
2541 Tracepoints-related commands are now fully documented in the GDB
2544 TUI, the Text-mode User Interface, is now documented in the manual.
2546 Tracepoints-related commands are now fully documented in the GDB
2549 The "GDB Internals" manual now has an index. It also includes
2550 documentation of `ui_out' functions, GDB coding standards, x86
2551 hardware watchpoints, and memory region attributes.
2553 * GDB's version number moved to ``version.in''
2555 The Makefile variable VERSION has been replaced by the file
2556 ``version.in''. People creating GDB distributions should update the
2557 contents of this file.
2561 GUD support is now a standard part of the EMACS distribution.
2563 *** Changes in GDB 5.0:
2565 * Improved support for debugging FP programs on x86 targets
2567 Unified and much-improved support for debugging floating-point
2568 programs on all x86 targets. In particular, ``info float'' now
2569 displays the FP registers in the same format on all x86 targets, with
2570 greater level of detail.
2572 * Improvements and bugfixes in hardware-assisted watchpoints
2574 It is now possible to watch array elements, struct members, and
2575 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2576 on x86 targets no longer erroneously trigger when the address is
2579 * Improvements in the native DJGPP version of GDB
2581 The distribution now includes all the scripts and auxiliary files
2582 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2583 machines ``out of the box''.
2585 The DJGPP version can now debug programs that use signals. It is
2586 possible to catch signals that happened in the debuggee, deliver
2587 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2588 would kill the program being debugged.) Programs that hook hardware
2589 interrupts (keyboard, timer, etc.) can also be debugged.
2591 It is now possible to debug DJGPP programs that redirect their
2592 standard handles or switch them to raw (as opposed to cooked) mode, or
2593 even close them. The command ``run < foo > bar'' works as expected,
2594 and ``info terminal'' reports useful information about the debuggee's
2595 terminal, including raw/cooked mode, redirection, etc.
2597 The DJGPP version now uses termios functions for console I/O, which
2598 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2601 DOS-style file names with drive letters are now fully supported by
2604 It is now possible to debug DJGPP programs that switch their working
2605 directory. It is also possible to rerun the debuggee any number of
2606 times without restarting GDB; thus, you can use the same setup,
2607 breakpoints, etc. for many debugging sessions.
2609 * New native configurations
2611 ARM GNU/Linux arm*-*-linux*
2612 PowerPC GNU/Linux powerpc-*-linux*
2616 Motorola MCore mcore-*-*
2617 x86 VxWorks i[3456]86-*-vxworks*
2618 PowerPC VxWorks powerpc-*-vxworks*
2619 TI TMS320C80 tic80-*-*
2621 * OBSOLETE configurations
2623 Altos 3068 m68*-altos-*
2624 Convex c1-*-*, c2-*-*
2626 ARM RISCix arm-*-* (as host)
2629 Configurations that have been declared obsolete will be commented out,
2630 but the code will be left in place. If there is no activity to revive
2631 these configurations before the next release of GDB, the sources will
2632 be permanently REMOVED.
2634 * Gould support removed
2636 Support for the Gould PowerNode and NP1 has been removed.
2638 * New features for SVR4
2640 On SVR4 native platforms (such as Solaris), if you attach to a process
2641 without first loading a symbol file, GDB will now attempt to locate and
2642 load symbols from the running process's executable file.
2644 * Many C++ enhancements
2646 C++ support has been greatly improved. Overload resolution now works properly
2647 in almost all cases. RTTI support is on the way.
2649 * Remote targets can connect to a sub-program
2651 A popen(3) style serial-device has been added. This device starts a
2652 sub-process (such as a stand-alone simulator) and then communicates
2653 with that. The sub-program to run is specified using the syntax
2654 ``|<program> <args>'' vis:
2656 (gdb) set remotedebug 1
2657 (gdb) target extended-remote |mn10300-elf-sim program-args
2659 * MIPS 64 remote protocol
2661 A long standing bug in the mips64 remote protocol where by GDB
2662 expected certain 32 bit registers (ex SR) to be transfered as 32
2663 instead of 64 bits has been fixed.
2665 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2666 added to provide backward compatibility with older versions of GDB.
2668 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2670 The command ``set remotebinarydownload'' command has been replaced by
2671 ``set remote X-packet''. Other commands in ``set remote'' family
2672 include ``set remote P-packet''.
2674 * Breakpoint commands accept ranges.
2676 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2677 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2678 ``tracepoint passcount'' also accepts a range of tracepoints.
2680 * ``apropos'' command added.
2682 The ``apropos'' command searches through command names and
2683 documentation strings, printing out matches, making it much easier to
2684 try to find a command that does what you are looking for.
2688 A new machine oriented interface (MI) has been added to GDB. This
2689 interface is designed for debug environments running GDB as a separate
2690 process. This is part of the long term libGDB project. See the
2691 "GDB/MI" chapter of the GDB manual for further information. It can be
2692 enabled by configuring with:
2694 .../configure --enable-gdbmi
2696 *** Changes in GDB-4.18:
2698 * New native configurations
2700 HP-UX 10.20 hppa*-*-hpux10.20
2701 HP-UX 11.x hppa*-*-hpux11.0*
2702 M68K GNU/Linux m68*-*-linux*
2706 Fujitsu FR30 fr30-*-elf*
2707 Intel StrongARM strongarm-*-*
2708 Mitsubishi D30V d30v-*-*
2710 * OBSOLETE configurations
2712 Gould PowerNode, NP1 np1-*-*, pn-*-*
2714 Configurations that have been declared obsolete will be commented out,
2715 but the code will be left in place. If there is no activity to revive
2716 these configurations before the next release of GDB, the sources will
2717 be permanently REMOVED.
2721 As a compatibility experiment, GDB's source files buildsym.h and
2722 buildsym.c have been converted to pure standard C, no longer
2723 containing any K&R compatibility code. We believe that all systems in
2724 use today either come with a standard C compiler, or have a GCC port
2725 available. If this is not true, please report the affected
2726 configuration to bug-gdb@gnu.org immediately. See the README file for
2727 information about getting a standard C compiler if you don't have one
2732 GDB now uses readline 2.2.
2734 * set extension-language
2736 You can now control the mapping between filename extensions and source
2737 languages by using the `set extension-language' command. For instance,
2738 you can ask GDB to treat .c files as C++ by saying
2739 set extension-language .c c++
2740 The command `info extensions' lists all of the recognized extensions
2741 and their associated languages.
2743 * Setting processor type for PowerPC and RS/6000
2745 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2746 you can use the `set processor' command to specify what variant of the
2747 PowerPC family you are debugging. The command
2751 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2752 following PowerPC and RS6000 variants:
2754 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2755 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2757 403GC IBM PowerPC 403GC
2758 505 Motorola PowerPC 505
2759 860 Motorola PowerPC 860 or 850
2760 601 Motorola PowerPC 601
2761 602 Motorola PowerPC 602
2762 603 Motorola/IBM PowerPC 603 or 603e
2763 604 Motorola PowerPC 604 or 604e
2764 750 Motorola/IBM PowerPC 750 or 750
2766 At the moment, this command just tells GDB what to name the
2767 special-purpose processor registers. Since almost all the affected
2768 registers are inaccessible to user-level programs, this command is
2769 only useful for remote debugging in its present form.
2773 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2774 more extensive support for HP-UX. Added features include shared
2775 library support, kernel threads and hardware watchpoints for 11.00,
2776 support for HP's ANSI C and C++ compilers, and a compatibility mode
2777 for xdb and dbx commands.
2781 HP's donation includes the new concept of catchpoints, which is a
2782 generalization of the old catch command. On HP-UX, it is now possible
2783 to catch exec, fork, and vfork, as well as library loading.
2785 This means that the existing catch command has changed; its first
2786 argument now specifies the type of catch to be set up. See the
2787 output of "help catch" for a list of catchpoint types.
2789 * Debugging across forks
2791 On HP-UX, you can choose which process to debug when a fork() happens
2796 HP has donated a curses-based terminal user interface (TUI). To get
2797 it, build with --enable-tui. Although this can be enabled for any
2798 configuration, at present it only works for native HP debugging.
2800 * GDB remote protocol additions
2802 A new protocol packet 'X' that writes binary data is now available.
2803 Default behavior is to try 'X', then drop back to 'M' if the stub
2804 fails to respond. The settable variable `remotebinarydownload'
2805 allows explicit control over the use of 'X'.
2807 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2808 full 64-bit address. The command
2810 set remoteaddresssize 32
2812 can be used to revert to the old behaviour. For existing remote stubs
2813 the change should not be noticed, as the additional address information
2816 In order to assist in debugging stubs, you may use the maintenance
2817 command `packet' to send any text string to the stub. For instance,
2819 maint packet heythere
2821 sends the packet "$heythere#<checksum>". Note that it is very easy to
2822 disrupt a debugging session by sending the wrong packet at the wrong
2825 The compare-sections command allows you to compare section data on the
2826 target to what is in the executable file without uploading or
2827 downloading, by comparing CRC checksums.
2829 * Tracing can collect general expressions
2831 You may now collect general expressions at tracepoints. This requires
2832 further additions to the target-side stub; see tracepoint.c and
2833 doc/agentexpr.texi for further details.
2835 * mask-address variable for Mips
2837 For Mips targets, you may control the zeroing of the upper 32 bits of
2838 a 64-bit address by entering `set mask-address on'. This is mainly
2839 of interest to users of embedded R4xxx and R5xxx processors.
2841 * Higher serial baud rates
2843 GDB's serial code now allows you to specify baud rates 57600, 115200,
2844 230400, and 460800 baud. (Note that your host system may not be able
2845 to achieve all of these rates.)
2849 The i960 configuration now includes an initial implementation of a
2850 builtin simulator, contributed by Jim Wilson.
2853 *** Changes in GDB-4.17:
2855 * New native configurations
2857 Alpha GNU/Linux alpha*-*-linux*
2858 Unixware 2.x i[3456]86-unixware2*
2859 Irix 6.x mips*-sgi-irix6*
2860 PowerPC GNU/Linux powerpc-*-linux*
2861 PowerPC Solaris powerpcle-*-solaris*
2862 Sparc GNU/Linux sparc-*-linux*
2863 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2867 Argonaut Risc Chip (ARC) arc-*-*
2868 Hitachi H8/300S h8300*-*-*
2869 Matsushita MN10200 w/simulator mn10200-*-*
2870 Matsushita MN10300 w/simulator mn10300-*-*
2871 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2872 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2873 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2874 Mitsubishi D10V w/simulator d10v-*-*
2875 Mitsubishi M32R/D w/simulator m32r-*-elf*
2876 Tsqware Sparclet sparclet-*-*
2877 NEC V850 w/simulator v850-*-*
2879 * New debugging protocols
2881 ARM with RDI protocol arm*-*-*
2882 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2883 DDB and LSI variants of PMON protocol mips*-*-*
2884 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2885 PowerPC with SDS protocol powerpc{,le}-*-eabi
2886 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2890 All configurations can now understand and use the DWARF 2 debugging
2891 format. The choice is automatic, if the symbol file contains DWARF 2
2896 GDB now includes basic Java language support. This support is
2897 only useful with Java compilers that produce native machine code.
2899 * solib-absolute-prefix and solib-search-path
2901 For SunOS and SVR4 shared libraries, you may now set the prefix for
2902 loading absolute shared library symbol files, and the search path for
2903 locating non-absolute shared library symbol files.
2905 * Live range splitting
2907 GDB can now effectively debug code for which GCC has performed live
2908 range splitting as part of its optimization. See gdb/doc/LRS for
2909 more details on the expected format of the stabs information.
2913 GDB's support for the GNU Hurd, including thread debugging, has been
2914 updated to work with current versions of the Hurd.
2918 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2919 instruction set. ARM GDB automatically detects when Thumb
2920 instructions are in use, and adjusts disassembly and backtracing
2925 GDB's MIPS target configurations now handle the MIP16 16-bit
2930 GDB now includes support for overlays; if an executable has been
2931 linked such that multiple sections are based at the same address, GDB
2932 will decide which section to use for symbolic info. You can choose to
2933 control the decision manually, using overlay commands, or implement
2934 additional target-side support and use "overlay load-target" to bring
2935 in the overlay mapping. Do "help overlay" for more detail.
2939 The command "info symbol <address>" displays information about
2940 the symbol at the specified address.
2944 The standard remote protocol now includes an extension that allows
2945 asynchronous collection and display of trace data. This requires
2946 extensive support in the target-side debugging stub. Tracing mode
2947 includes a new interaction mode in GDB and new commands: see the
2948 file tracepoint.c for more details.
2952 Configurations for embedded MIPS now include a simulator contributed
2953 by Cygnus Solutions. The simulator supports the instruction sets
2954 of most MIPS variants.
2958 Sparc configurations may now include the ERC32 simulator contributed
2959 by the European Space Agency. The simulator is not built into
2960 Sparc targets by default; configure with --enable-sim to include it.
2964 For target configurations that may include multiple variants of a
2965 basic architecture (such as MIPS and SH), you may now set the
2966 architecture explicitly. "set arch" sets, "info arch" lists
2967 the possible architectures.
2969 *** Changes in GDB-4.16:
2971 * New native configurations
2973 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2974 M68K NetBSD m68k-*-netbsd*
2975 PowerPC AIX 4.x powerpc-*-aix*
2976 PowerPC MacOS powerpc-*-macos*
2977 PowerPC Windows NT powerpcle-*-cygwin32
2978 RS/6000 AIX 4.x rs6000-*-aix4*
2982 ARM with RDP protocol arm-*-*
2983 I960 with MON960 i960-*-coff
2984 MIPS VxWorks mips*-*-vxworks*
2985 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2986 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2988 Matra Sparclet sparclet-*-*
2992 The powerpc-eabi configuration now includes the PSIM simulator,
2993 contributed by Andrew Cagney, with assistance from Mike Meissner.
2994 PSIM is a very elaborate model of the PowerPC, including not only
2995 basic instruction set execution, but also details of execution unit
2996 performance and I/O hardware. See sim/ppc/README for more details.
3000 GDB now works with Solaris 2.5.
3002 * Windows 95/NT native
3004 GDB will now work as a native debugger on Windows 95 and Windows NT.
3005 To build it from source, you must use the "gnu-win32" environment,
3006 which uses a DLL to emulate enough of Unix to run the GNU tools.
3007 Further information, binaries, and sources are available at
3008 ftp.cygnus.com, under pub/gnu-win32.
3010 * dont-repeat command
3012 If a user-defined command includes the command `dont-repeat', then the
3013 command will not be repeated if the user just types return. This is
3014 useful if the command is time-consuming to run, so that accidental
3015 extra keystrokes don't run the same command many times.
3017 * Send break instead of ^C
3019 The standard remote protocol now includes an option to send a break
3020 rather than a ^C to the target in order to interrupt it. By default,
3021 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3023 * Remote protocol timeout
3025 The standard remote protocol includes a new variable `remotetimeout'
3026 that allows you to set the number of seconds before GDB gives up trying
3027 to read from the target. The default value is 2.
3029 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3031 By default GDB will automatically keep track of objects as they are
3032 loaded and unloaded by the dynamic linker. By using the command `set
3033 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3034 when shared library events occur, thus allowing you to set breakpoints
3035 in shared libraries which are explicitly loaded by the inferior.
3037 Note this feature does not work on hpux8. On hpux9 you must link
3038 /usr/lib/end.o into your program. This feature should work
3039 automatically on hpux10.
3041 * Irix 5.x hardware watchpoint support
3043 Irix 5 configurations now support the use of hardware watchpoints.
3045 * Mips protocol "SYN garbage limit"
3047 When debugging a Mips target using the `target mips' protocol, you
3048 may set the number of characters that GDB will ignore by setting
3049 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3050 every character. The default value is 1050.
3052 * Recording and replaying remote debug sessions
3054 If you set `remotelogfile' to the name of a file, gdb will write to it
3055 a recording of a remote debug session. This recording may then be
3056 replayed back to gdb using "gdbreplay". See gdbserver/README for
3057 details. This is useful when you have a problem with GDB while doing
3058 remote debugging; you can make a recording of the session and send it
3059 to someone else, who can then recreate the problem.
3061 * Speedups for remote debugging
3063 GDB includes speedups for downloading and stepping MIPS systems using
3064 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3065 and more efficient S-record downloading.
3067 * Memory use reductions and statistics collection
3069 GDB now uses less memory and reports statistics about memory usage.
3070 Try the `maint print statistics' command, for example.
3072 *** Changes in GDB-4.15:
3074 * Psymtabs for XCOFF
3076 The symbol reader for AIX GDB now uses partial symbol tables. This
3077 can greatly improve startup time, especially for large executables.
3079 * Remote targets use caching
3081 Remote targets now use a data cache to speed up communication with the
3082 remote side. The data cache could lead to incorrect results because
3083 it doesn't know about volatile variables, thus making it impossible to
3084 debug targets which use memory mapped I/O devices. `set remotecache
3085 off' turns the the data cache off.
3087 * Remote targets may have threads
3089 The standard remote protocol now includes support for multiple threads
3090 in the target system, using new protocol commands 'H' and 'T'. See
3091 gdb/remote.c for details.
3095 If GDB is configured with `--enable-netrom', then it will include
3096 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3097 acts as though it is a bank of ROM on the target board, but you can
3098 write into it over the network. GDB's support consists only of
3099 support for fast loading into the emulated ROM; to debug, you must use
3100 another protocol, such as standard remote protocol. The usual
3101 sequence is something like
3103 target nrom <netrom-hostname>
3105 target remote <netrom-hostname>:1235
3109 GDB now includes support for the Apple Macintosh, as a host only. It
3110 may be run as either an MPW tool or as a standalone application, and
3111 it can debug through the serial port. All the usual GDB commands are
3112 available, but to the target command, you must supply "serial" as the
3113 device type instead of "/dev/ttyXX". See mpw-README in the main
3114 directory for more information on how to build. The MPW configuration
3115 scripts */mpw-config.in support only a few targets, and only the
3116 mips-idt-ecoff target has been tested.
3120 GDB configuration now uses autoconf. This is not user-visible,
3121 but does simplify configuration and building.
3125 GDB now supports hpux10.
3127 *** Changes in GDB-4.14:
3129 * New native configurations
3131 x86 FreeBSD i[345]86-*-freebsd
3132 x86 NetBSD i[345]86-*-netbsd
3133 NS32k NetBSD ns32k-*-netbsd
3134 Sparc NetBSD sparc-*-netbsd
3138 A29K VxWorks a29k-*-vxworks
3139 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3140 CPU32 EST-300 emulator m68*-*-est*
3141 PowerPC ELF powerpc-*-elf
3144 * Alpha OSF/1 support for procfs
3146 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3147 possible to attach to running processes. As the mounting of the /proc
3148 filesystem is optional on the Alpha, GDB automatically determines
3149 the availability of /proc during startup. This can lead to problems
3150 if /proc is unmounted after GDB has been started.
3152 * Arguments to user-defined commands
3154 User commands may accept up to 10 arguments separated by whitespace.
3155 Arguments are accessed within the user command via $arg0..$arg9. A
3158 print $arg0 + $arg1 + $arg2
3160 To execute the command use:
3163 Defines the command "adder" which prints the sum of its three arguments.
3164 Note the arguments are text substitutions, so they may reference variables,
3165 use complex expressions, or even perform inferior function calls.
3167 * New `if' and `while' commands
3169 This makes it possible to write more sophisticated user-defined
3170 commands. Both commands take a single argument, which is the
3171 expression to evaluate, and must be followed by the commands to
3172 execute, one per line, if the expression is nonzero, the list being
3173 terminated by the word `end'. The `if' command list may include an
3174 `else' word, which causes the following commands to be executed only
3175 if the expression is zero.
3177 * Fortran source language mode
3179 GDB now includes partial support for Fortran 77. It will recognize
3180 Fortran programs and can evaluate a subset of Fortran expressions, but
3181 variables and functions may not be handled correctly. GDB will work
3182 with G77, but does not yet know much about symbols emitted by other
3185 * Better HPUX support
3187 Most debugging facilities now work on dynamic executables for HPPAs
3188 running hpux9 or later. You can attach to running dynamically linked
3189 processes, but by default the dynamic libraries will be read-only, so
3190 for instance you won't be able to put breakpoints in them. To change
3191 that behavior do the following before running the program:
3197 This will cause the libraries to be mapped private and read-write.
3198 To revert to the normal behavior, do this:
3204 You cannot set breakpoints or examine data in the library until after
3205 the library is loaded if the function/data symbols do not have
3208 GDB can now also read debug symbols produced by the HP C compiler on
3209 HPPAs (sorry, no C++, Fortran or 68k support).
3211 * Target byte order now dynamically selectable
3213 You can choose which byte order to use with a target system, via the
3214 commands "set endian big" and "set endian little", and you can see the
3215 current setting by using "show endian". You can also give the command
3216 "set endian auto", in which case GDB will use the byte order
3217 associated with the executable. Currently, only embedded MIPS
3218 configurations support dynamic selection of target byte order.
3220 * New DOS host serial code
3222 This version uses DPMI interrupts to handle buffered I/O, so you
3223 no longer need to run asynctsr when debugging boards connected to
3226 *** Changes in GDB-4.13:
3228 * New "complete" command
3230 This lists all the possible completions for the rest of the line, if it
3231 were to be given as a command itself. This is intended for use by emacs.
3233 * Trailing space optional in prompt
3235 "set prompt" no longer adds a space for you after the prompt you set. This
3236 allows you to set a prompt which ends in a space or one that does not.
3238 * Breakpoint hit counts
3240 "info break" now displays a count of the number of times the breakpoint
3241 has been hit. This is especially useful in conjunction with "ignore"; you
3242 can ignore a large number of breakpoint hits, look at the breakpoint info
3243 to see how many times the breakpoint was hit, then run again, ignoring one
3244 less than that number, and this will get you quickly to the last hit of
3247 * Ability to stop printing at NULL character
3249 "set print null-stop" will cause GDB to stop printing the characters of
3250 an array when the first NULL is encountered. This is useful when large
3251 arrays actually contain only short strings.
3253 * Shared library breakpoints
3255 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3256 breakpoints in shared libraries before the executable is run.
3258 * Hardware watchpoints
3260 There is a new hardware breakpoint for the watch command for sparclite
3261 targets. See gdb/sparclite/hw_breakpoint.note.
3263 Hardware watchpoints are also now supported under GNU/Linux.
3267 Annotations have been added. These are for use with graphical interfaces,
3268 and are still experimental. Currently only gdba.el uses these.
3270 * Improved Irix 5 support
3272 GDB now works properly with Irix 5.2.
3274 * Improved HPPA support
3276 GDB now works properly with the latest GCC and GAS.
3278 * New native configurations
3280 Sequent PTX4 i[34]86-sequent-ptx4
3281 HPPA running OSF/1 hppa*-*-osf*
3282 Atari TT running SVR4 m68*-*-sysv4*
3283 RS/6000 LynxOS rs6000-*-lynxos*
3287 OS/9000 i[34]86-*-os9k
3288 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3291 * Hitachi SH7000 and E7000-PC ICE support
3293 There is now support for communicating with the Hitachi E7000-PC ICE.
3294 This is available automatically when GDB is configured for the SH.
3298 As usual, a variety of small fixes and improvements, both generic
3299 and configuration-specific. See the ChangeLog for more detail.
3301 *** Changes in GDB-4.12:
3303 * Irix 5 is now supported
3307 GDB-4.12 on the HPPA has a number of changes which make it unable
3308 to debug the output from the currently released versions of GCC and
3309 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3310 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3311 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3314 *** Changes in GDB-4.11:
3316 * User visible changes:
3320 The "set remotedebug" option is now consistent between the mips remote
3321 target, remote targets using the gdb-specific protocol, UDI (AMD's
3322 debug protocol for the 29k) and the 88k bug monitor. It is now an
3323 integer specifying a debug level (normally 0 or 1, but 2 means more
3324 debugging info for the mips target).
3326 * DEC Alpha native support
3328 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3329 debug info, but GDB works fairly well with the DEC compiler and should
3330 work with a future GCC release. See the README file for a few
3331 Alpha-specific notes.
3333 * Preliminary thread implementation
3335 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3337 * LynxOS native and target support for 386
3339 This release has been hosted on LynxOS 2.2, and also can be configured
3340 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3343 * Improvements in C++ mangling/demangling.
3345 This release has much better g++ debugging, specifically in name
3346 mangling/demangling, virtual function calls, print virtual table,
3347 call methods, ...etc.
3349 *** Changes in GDB-4.10:
3351 * User visible changes:
3353 Remote debugging using the GDB-specific (`target remote') protocol now
3354 supports the `load' command. This is only useful if you have some
3355 other way of getting the stub to the target system, and you can put it
3356 somewhere in memory where it won't get clobbered by the download.
3358 Filename completion now works.
3360 When run under emacs mode, the "info line" command now causes the
3361 arrow to point to the line specified. Also, "info line" prints
3362 addresses in symbolic form (as well as hex).
3364 All vxworks based targets now support a user settable option, called
3365 vxworks-timeout. This option represents the number of seconds gdb
3366 should wait for responses to rpc's. You might want to use this if
3367 your vxworks target is, perhaps, a slow software simulator or happens
3368 to be on the far side of a thin network line.
3372 This release contains support for using a DEC alpha as a GDB host for
3373 cross debugging. Native alpha debugging is not supported yet.
3376 *** Changes in GDB-4.9:
3380 This is the first GDB release which is accompanied by a matching testsuite.
3381 The testsuite requires installation of dejagnu, which should be available
3382 via ftp from most sites that carry GNU software.
3386 'Cfront' style demangling has had its name changed to 'ARM' style, to
3387 emphasize that it was written from the specifications in the C++ Annotated
3388 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3389 disclaimers, it still generated too much confusion with users attempting to
3390 use gdb with AT&T cfront.
3394 GDB now uses a standard remote interface to a simulator library.
3395 So far, the library contains simulators for the Zilog Z8001/2, the
3396 Hitachi H8/300, H8/500 and Super-H.
3398 * New targets supported
3400 H8/300 simulator h8300-hitachi-hms or h8300hms
3401 H8/500 simulator h8500-hitachi-hms or h8500hms
3402 SH simulator sh-hitachi-hms or sh
3403 Z8000 simulator z8k-zilog-none or z8ksim
3404 IDT MIPS board over serial line mips-idt-ecoff
3406 Cross-debugging to GO32 targets is supported. It requires a custom
3407 version of the i386-stub.c module which is integrated with the
3408 GO32 memory extender.
3410 * New remote protocols
3412 MIPS remote debugging protocol.
3414 * New source languages supported
3416 This version includes preliminary support for Chill, a Pascal like language
3417 used by telecommunications companies. Chill support is also being integrated
3418 into the GNU compiler, but we don't know when it will be publically available.
3421 *** Changes in GDB-4.8:
3423 * HP Precision Architecture supported
3425 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3426 version of this support was available as a set of patches from the
3427 University of Utah. GDB does not support debugging of programs
3428 compiled with the HP compiler, because HP will not document their file
3429 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3430 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3432 Many problems in the preliminary version have been fixed.
3434 * Faster and better demangling
3436 We have improved template demangling and fixed numerous bugs in the GNU style
3437 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3438 character types (wchar_t) are now supported. Demangling of each symbol is now
3439 only done once, and is cached when the symbol table for a file is read in.
3440 This results in a small increase in memory usage for C programs, a moderate
3441 increase in memory usage for C++ programs, and a fantastic speedup in
3444 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3445 from the specifications in the Annotated Reference Manual, which AT&T's
3446 compiler does not actually implement.
3448 * G++ multiple inheritance compiler problem
3450 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3451 inheritance lattices was reworked to properly discover ambiguities. We
3452 recently found an example which causes this new algorithm to fail in a
3453 very subtle way, producing bad debug information for those classes.
3454 The file 'gcc.patch' (in this directory) can be applied to gcc to
3455 circumvent the problem. A future GCC release will contain a complete
3458 The previous G++ debug info problem (mentioned below for the gdb-4.7
3459 release) is fixed in gcc version 2.3.2.
3461 * Improved configure script
3463 The `configure' script will now attempt to guess your system type if
3464 you don't supply a host system type. The old scheme of supplying a
3465 host system triplet is preferable over using this. All the magic is
3466 done in the new `config.guess' script. Examine it for details.
3468 We have also brought our configure script much more in line with the FSF's
3469 version. It now supports the --with-xxx options. In particular,
3470 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3471 The resulting GDB will not be able to read arbitrary object file formats --
3472 only the format ``expected'' to be used on the configured target system.
3473 We hope to make this the default in a future release.
3475 * Documentation improvements
3477 There's new internal documentation on how to modify GDB, and how to
3478 produce clean changes to the code. We implore people to read it
3479 before submitting changes.
3481 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3482 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3483 `info' files are also provided. To build `info' files from scratch,
3484 you will need the latest `makeinfo' release, which will be available in
3485 a future texinfo-X.Y release.
3487 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3488 We're not sure exactly which versions have this problem, but it has
3489 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3490 or better. If that isn't possible, there is a patch in
3491 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3492 around this problem.
3496 GDB now supports array constants that can be used in expressions typed in by
3497 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3498 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3501 The new directory `gdb/sparclite' contains a program that demonstrates
3502 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3504 * New native hosts supported
3506 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3507 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3509 * New targets supported
3511 AMD 29k family via UDI a29k-amd-udi or udi29k
3513 * New file formats supported
3515 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3516 HPUX core files, and SCO 3.2v2 core files.
3520 Attaching to processes now works again; thanks for the many bug reports.
3522 We have also stomped on a bunch of core dumps caused by
3523 printf_filtered("%s") problems.
3525 We eliminated a copyright problem on the rpc and ptrace header files
3526 for VxWorks, which was discovered at the last minute during the 4.7
3527 release. You should now be able to build a VxWorks GDB.
3529 You can now interrupt gdb while an attached process is running. This
3530 will cause the attached process to stop, and give control back to GDB.
3532 We fixed problems caused by using too many file descriptors
3533 for reading symbols from object files and libraries. This was
3534 especially a problem for programs that used many (~100) shared
3537 The `step' command now only enters a subroutine if there is line number
3538 information for the subroutine. Otherwise it acts like the `next'
3539 command. Previously, `step' would enter subroutines if there was
3540 any debugging information about the routine. This avoids problems
3541 when using `cc -g1' on MIPS machines.
3543 * Internal improvements
3545 GDB's internal interfaces have been improved to make it easier to support
3546 debugging of multiple languages in the future.
3548 GDB now uses a common structure for symbol information internally.
3549 Minimal symbols (derived from linkage symbols in object files), partial
3550 symbols (from a quick scan of debug information), and full symbols
3551 contain a common subset of information, making it easier to write
3552 shared code that handles any of them.
3554 * New command line options
3556 We now accept --silent as an alias for --quiet.
3560 The memory-mapped-malloc library is now licensed under the GNU Library
3561 General Public License.
3563 *** Changes in GDB-4.7:
3565 * Host/native/target split
3567 GDB has had some major internal surgery to untangle the support for
3568 hosts and remote targets. Now, when you configure GDB for a remote
3569 target, it will no longer load in all of the support for debugging
3570 local programs on the host. When fully completed and tested, this will
3571 ensure that arbitrary host/target combinations are possible.
3573 The primary conceptual shift is to separate the non-portable code in
3574 GDB into three categories. Host specific code is required any time GDB
3575 is compiled on that host, regardless of the target. Target specific
3576 code relates to the peculiarities of the target, but can be compiled on
3577 any host. Native specific code is everything else: it can only be
3578 built when the host and target are the same system. Child process
3579 handling and core file support are two common `native' examples.
3581 GDB's use of /proc for controlling Unix child processes is now cleaner.
3582 It has been split out into a single module under the `target_ops' vector,
3583 plus two native-dependent functions for each system that uses /proc.
3585 * New hosts supported
3587 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3588 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3589 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3591 * New targets supported
3593 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3594 68030 and CPU32 m68030-*-*, m68332-*-*
3596 * New native hosts supported
3598 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3599 (386bsd is not well tested yet)
3600 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3602 * New file formats supported
3604 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3605 supports reading of `a.out.adobe' object files, which are an a.out
3606 format extended with minimal information about multiple sections.
3610 `show copying' is the same as the old `info copying'.
3611 `show warranty' is the same as `info warrantee'.
3612 These were renamed for consistency. The old commands continue to work.
3614 `info handle' is a new alias for `info signals'.
3616 You can now define pre-command hooks, which attach arbitrary command
3617 scripts to any command. The commands in the hook will be executed
3618 prior to the user's command. You can also create a hook which will be
3619 executed whenever the program stops. See gdb.texinfo.
3623 We now deal with Cfront style name mangling, and can even extract type
3624 info from mangled symbols. GDB can automatically figure out which
3625 symbol mangling style your C++ compiler uses.
3627 Calling of methods and virtual functions has been improved as well.
3631 The crash that occured when debugging Sun Ansi-C compiled binaries is
3632 fixed. This was due to mishandling of the extra N_SO stabs output
3635 We also finally got Ultrix 4.2 running in house, and fixed core file
3636 support, with help from a dozen people on the net.
3638 John M. Farrell discovered that the reason that single-stepping was so
3639 slow on all of the Mips based platforms (primarily SGI and DEC) was
3640 that we were trying to demangle and lookup a symbol used for internal
3641 purposes on every instruction that was being stepped through. Changing
3642 the name of that symbol so that it couldn't be mistaken for a C++
3643 mangled symbol sped things up a great deal.
3645 Rich Pixley sped up symbol lookups in general by getting much smarter
3646 about when C++ symbol mangling is necessary. This should make symbol
3647 completion (TAB on the command line) much faster. It's not as fast as
3648 we'd like, but it's significantly faster than gdb-4.6.
3652 A new user controllable variable 'call_scratch_address' can
3653 specify the location of a scratch area to be used when GDB
3654 calls a function in the target. This is necessary because the
3655 usual method of putting the scratch area on the stack does not work
3656 in systems that have separate instruction and data spaces.
3658 We integrated changes to support the 29k UDI (Universal Debugger
3659 Interface), but discovered at the last minute that we didn't have all
3660 of the appropriate copyright paperwork. We are working with AMD to
3661 resolve this, and hope to have it available soon.
3665 We have sped up the remote serial line protocol, especially for targets
3666 with lots of registers. It now supports a new `expedited status' ('T')
3667 message which can be used in place of the existing 'S' status message.
3668 This allows the remote stub to send only the registers that GDB
3669 needs to make a quick decision about single-stepping or conditional
3670 breakpoints, eliminating the need to fetch the entire register set for
3671 each instruction being stepped through.
3673 The GDB remote serial protocol now implements a write-through cache for
3674 registers, only re-reading the registers if the target has run.
3676 There is also a new remote serial stub for SPARC processors. You can
3677 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3678 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3679 processor with a serial port.
3683 Configure.in files have become much easier to read and modify. A new
3684 `table driven' format makes it more obvious what configurations are
3685 supported, and what files each one uses.
3689 There is a new opcodes library which will eventually contain all of the
3690 disassembly routines and opcode tables. At present, it only contains
3691 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3692 disassembler (binutils/objdump) to share these routines.
3694 The libiberty library is now copylefted under the GNU Library General
3695 Public License. This allows more liberal use, and was done so libg++
3696 can use it. This makes no difference to GDB, since the Library License
3697 grants all the rights from the General Public License.
3701 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3702 reference to the stabs symbol info used by the debugger. It is (as far
3703 as we know) the only published document on this fascinating topic. We
3704 encourage you to read it, compare it to the stabs information on your
3705 system, and send improvements on the document in general (to
3706 bug-gdb@prep.ai.mit.edu).
3708 And, of course, many bugs have been fixed.
3711 *** Changes in GDB-4.6:
3713 * Better support for C++ function names
3715 GDB now accepts as input the "demangled form" of C++ overloaded function
3716 names and member function names, and can do command completion on such names
3717 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3718 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3719 Make use of command completion, it is your friend.
3721 GDB also now accepts a variety of C++ mangled symbol formats. They are
3722 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3723 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3724 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3725 for the list of formats.
3727 * G++ symbol mangling problem
3729 Recent versions of gcc have a bug in how they emit debugging information for
3730 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3731 directory) can be applied to gcc to fix the problem. Alternatively, if you
3732 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3733 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3734 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3737 * New 'maintenance' command
3739 All of the commands related to hacking GDB internals have been moved out of
3740 the main command set, and now live behind the 'maintenance' command. This
3741 can also be abbreviated as 'mt'. The following changes were made:
3743 dump-me -> maintenance dump-me
3744 info all-breakpoints -> maintenance info breakpoints
3745 printmsyms -> maintenance print msyms
3746 printobjfiles -> maintenance print objfiles
3747 printpsyms -> maintenance print psymbols
3748 printsyms -> maintenance print symbols
3750 The following commands are new:
3752 maintenance demangle Call internal GDB demangler routine to
3753 demangle a C++ link name and prints the result.
3754 maintenance print type Print a type chain for a given symbol
3756 * Change to .gdbinit file processing
3758 We now read the $HOME/.gdbinit file before processing the argv arguments
3759 (e.g. reading symbol files or core files). This allows global parameters to
3760 be set, which will apply during the symbol reading. The ./.gdbinit is still
3761 read after argv processing.
3763 * New hosts supported
3765 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3767 GNU/Linux support i386-unknown-linux or linux
3769 We are also including code to support the HP/PA running BSD and HPUX. This
3770 is almost guaranteed not to work, as we didn't have time to test or build it
3771 for this release. We are including it so that the more adventurous (or
3772 masochistic) of you can play with it. We also had major problems with the
3773 fact that the compiler that we got from HP doesn't support the -g option.
3776 * New targets supported
3778 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3780 * More smarts about finding #include files
3782 GDB now remembers the compilation directory for all include files, and for
3783 all files from which C is generated (like yacc and lex sources). This
3784 greatly improves GDB's ability to find yacc/lex sources, and include files,
3785 especially if you are debugging your program from a directory different from
3786 the one that contains your sources.
3788 We also fixed a bug which caused difficulty with listing and setting
3789 breakpoints in include files which contain C code. (In the past, you had to
3790 try twice in order to list an include file that you hadn't looked at before.)
3792 * Interesting infernals change
3794 GDB now deals with arbitrary numbers of sections, where the symbols for each
3795 section must be relocated relative to that section's landing place in the
3796 target's address space. This work was needed to support ELF with embedded
3797 stabs used by Solaris-2.0.
3799 * Bug fixes (of course!)
3801 There have been loads of fixes for the following things:
3802 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3803 i960, stabs, DOS(GO32), procfs, etc...
3805 See the ChangeLog for details.
3807 *** Changes in GDB-4.5:
3809 * New machines supported (host and target)
3811 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3813 SGI Irix-4.x mips-sgi-irix4 or iris4
3815 * New malloc package
3817 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3818 Mmalloc is capable of handling mutiple heaps of memory. It is also
3819 capable of saving a heap to a file, and then mapping it back in later.
3820 This can be used to greatly speedup the startup of GDB by using a
3821 pre-parsed symbol table which lives in a mmalloc managed heap. For
3822 more details, please read mmalloc/mmalloc.texi.
3826 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3827 'help info proc' for details.
3829 * MIPS ecoff symbol table format
3831 The code that reads MIPS symbol table format is now supported on all hosts.
3832 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3835 * File name changes for MS-DOS
3837 Many files in the config directories have been renamed to make it easier to
3838 support GDB on MS-DOSe systems (which have very restrictive file name
3839 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3840 environment) is close to working but has some remaining problems. Note
3841 that debugging of DOS programs is not supported, due to limitations
3842 in the ``operating system'', but it can be used to host cross-debugging.
3844 * Cross byte order fixes
3846 Many fixes have been made to support cross debugging of Sparc and MIPS
3847 targets from hosts whose byte order differs.
3849 * New -mapped and -readnow options
3851 If memory-mapped files are available on your system through the 'mmap'
3852 system call, you can use the -mapped option on the `file' or
3853 `symbol-file' commands to cause GDB to write the symbols from your
3854 program into a reusable file. If the program you are debugging is
3855 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3856 Future GDB debugging sessions will notice the presence of this file,
3857 and will quickly map in symbol information from it, rather than reading
3858 the symbol table from the executable program. Using the '-mapped'
3859 option in a GDB `file' or `symbol-file' command has the same effect as
3860 starting GDB with the '-mapped' command-line option.
3862 You can cause GDB to read the entire symbol table immediately by using
3863 the '-readnow' option with any of the commands that load symbol table
3864 information (or on the GDB command line). This makes the command
3865 slower, but makes future operations faster.
3867 The -mapped and -readnow options are typically combined in order to
3868 build a `fred.syms' file that contains complete symbol information.
3869 A simple GDB invocation to do nothing but build a `.syms' file for future
3872 gdb -batch -nx -mapped -readnow programname
3874 The `.syms' file is specific to the host machine on which GDB is run.
3875 It holds an exact image of GDB's internal symbol table. It cannot be
3876 shared across multiple host platforms.
3878 * longjmp() handling
3880 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3881 siglongjmp() without losing control. This feature has not yet been ported to
3882 all systems. It currently works on many 386 platforms, all MIPS-based
3883 platforms (SGI, DECstation, etc), and Sun3/4.
3887 Preliminary work has been put in to support the new Solaris OS from Sun. At
3888 this time, it can control and debug processes, but it is not capable of
3893 As always, many many bug fixes. The major areas were with g++, and mipsread.
3894 People using the MIPS-based platforms should experience fewer mysterious
3895 crashes and trashed symbol tables.
3897 *** Changes in GDB-4.4:
3899 * New machines supported (host and target)
3901 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3903 BSD Reno on Vax vax-dec-bsd
3904 Ultrix on Vax vax-dec-ultrix
3906 * New machines supported (target)
3908 AMD 29000 embedded, using EBMON a29k-none-none
3912 GDB continues to improve its handling of C++. `References' work better.
3913 The demangler has also been improved, and now deals with symbols mangled as
3914 per the Annotated C++ Reference Guide.
3916 GDB also now handles `stabs' symbol information embedded in MIPS
3917 `ecoff' symbol tables. Since the ecoff format was not easily
3918 extensible to handle new languages such as C++, this appeared to be a
3919 good way to put C++ debugging info into MIPS binaries. This option
3920 will be supported in the GNU C compiler, version 2, when it is
3923 * New features for SVR4
3925 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3926 shared libraries. Debugging dynamically linked programs should present
3927 only minor differences from debugging statically linked programs.
3929 The `info proc' command will print out information about any process
3930 on an SVR4 system (including the one you are debugging). At the moment,
3931 it prints the address mappings of the process.
3933 If you bring up GDB on another SVR4 system, please send mail to
3934 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3936 * Better dynamic linking support in SunOS
3938 Reading symbols from shared libraries which contain debugging symbols
3939 now works properly. However, there remain issues such as automatic
3940 skipping of `transfer vector' code during function calls, which
3941 make it harder to debug code in a shared library, than to debug the
3942 same code linked statically.
3946 GDB is now using the latest `getopt' routines from the FSF. This
3947 version accepts the -- prefix for options with long names. GDB will
3948 continue to accept the old forms (-option and +option) as well.
3949 Various single letter abbreviations for options have been explicity
3950 added to the option table so that they won't get overshadowed in the
3951 future by other options that begin with the same letter.
3955 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3956 Many assorted bugs have been handled. Many more remain to be handled.
3957 See the various ChangeLog files (primarily in gdb and bfd) for details.
3960 *** Changes in GDB-4.3:
3962 * New machines supported (host and target)
3964 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3965 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3966 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3968 * Almost SCO Unix support
3970 We had hoped to support:
3971 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3972 (except for core file support), but we discovered very late in the release
3973 that it has problems with process groups that render gdb unusable. Sorry
3974 about that. I encourage people to fix it and post the fixes.
3976 * Preliminary ELF and DWARF support
3978 GDB can read ELF object files on System V Release 4, and can handle
3979 debugging records for C, in DWARF format, in ELF files. This support
3980 is preliminary. If you bring up GDB on another SVR4 system, please
3981 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3986 GDB now uses the latest `readline' library. One user-visible change
3987 is that two tabs will list possible command completions, which previously
3988 required typing M-? (meta-question mark, or ESC ?).
3992 The `stepi' bug that many of you noticed has been squashed.
3993 Many bugs in C++ have been handled. Many more remain to be handled.
3994 See the various ChangeLog files (primarily in gdb and bfd) for details.
3996 * State of the MIPS world (in case you wondered):
3998 GDB can understand the symbol tables emitted by the compilers
3999 supplied by most vendors of MIPS-based machines, including DEC. These
4000 symbol tables are in a format that essentially nobody else uses.
4002 Some versions of gcc come with an assembler post-processor called
4003 mips-tfile. This program is required if you want to do source-level
4004 debugging of gcc-compiled programs. I believe FSF does not ship
4005 mips-tfile with gcc version 1, but it will eventually come with gcc
4008 Debugging of g++ output remains a problem. g++ version 1.xx does not
4009 really support it at all. (If you're lucky, you should be able to get
4010 line numbers and stack traces to work, but no parameters or local
4011 variables.) With some work it should be possible to improve the
4014 When gcc version 2 is released, you will have somewhat better luck.
4015 However, even then you will get confusing results for inheritance and
4018 We will eventually provide full debugging of g++ output on
4019 DECstations. This will probably involve some kind of stabs-in-ecoff
4020 encapulation, but the details have not been worked out yet.
4023 *** Changes in GDB-4.2:
4025 * Improved configuration
4027 Only one copy of `configure' exists now, and it is not self-modifying.
4028 Porting BFD is simpler.
4032 The `step' and `next' commands now only stop at the first instruction
4033 of a source line. This prevents the multiple stops that used to occur
4034 in switch statements, for-loops, etc. `Step' continues to stop if a
4035 function that has debugging information is called within the line.
4039 Lots of small bugs fixed. More remain.
4041 * New host supported (not target)
4043 Intel 386 PC clone running Mach i386-none-mach
4046 *** Changes in GDB-4.1:
4048 * Multiple source language support
4050 GDB now has internal scaffolding to handle several source languages.
4051 It determines the type of each source file from its filename extension,
4052 and will switch expression parsing and number formatting to match the
4053 language of the function in the currently selected stack frame.
4054 You can also specifically set the language to be used, with
4055 `set language c' or `set language modula-2'.
4059 GDB now has preliminary support for the GNU Modula-2 compiler,
4060 currently under development at the State University of New York at
4061 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4062 continue through the fall of 1991 and into 1992.
4064 Other Modula-2 compilers are currently not supported, and attempting to
4065 debug programs compiled with them will likely result in an error as the
4066 symbol table is read. Feel free to work on it, though!
4068 There are hooks in GDB for strict type checking and range checking,
4069 in the `Modula-2 philosophy', but they do not currently work.
4073 GDB can now write to executable and core files (e.g. patch
4074 a variable's value). You must turn this switch on, specify
4075 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4076 by assigning a new value to a variable. Modifications take
4079 * Automatic SunOS shared library reading
4081 When you run your program, GDB automatically determines where its
4082 shared libraries (if any) have been loaded, and reads their symbols.
4083 The `share' command is no longer needed. This also works when
4084 examining core files.
4088 You can specify the number of lines that the `list' command shows.
4091 * New machines supported (host and target)
4093 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4094 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4095 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4097 * New hosts supported (not targets)
4099 IBM RT/PC: romp-ibm-aix or rtpc
4101 * New targets supported (not hosts)
4103 AMD 29000 embedded with COFF a29k-none-coff
4104 AMD 29000 embedded with a.out a29k-none-aout
4105 Ultracomputer remote kernel debug a29k-nyu-kern
4107 * New remote interfaces
4113 *** Changes in GDB-4.0:
4117 Wide output is wrapped at good places to make the output more readable.
4119 Gdb now supports cross-debugging from a host machine of one type to a
4120 target machine of another type. Communication with the target system
4121 is over serial lines. The ``target'' command handles connecting to the
4122 remote system; the ``load'' command will download a program into the
4123 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4124 also supports debugging of realtime processes running under VxWorks,
4125 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4126 stub on the target system.
4128 New CPUs supported include the AMD 29000 and Intel 960.
4130 GDB now reads object files and symbol tables via a ``binary file''
4131 library, which allows a single copy of GDB to debug programs of multiple
4132 object file types such as a.out and coff.
4134 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4135 refcard.dvi and refcard.ps are available to format it).
4138 * Control-Variable user interface simplified
4140 All variables that control the operation of the debugger can be set
4141 by the ``set'' command, and displayed by the ``show'' command.
4143 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4144 ``Show prompt'' produces the response:
4145 Gdb's prompt is new-gdb=>.
4147 What follows are the NEW set commands. The command ``help set'' will
4148 print a complete list of old and new set commands. ``help set FOO''
4149 will give a longer description of the variable FOO. ``show'' will show
4150 all of the variable descriptions and their current settings.
4152 confirm on/off: Enables warning questions for operations that are
4153 hard to recover from, e.g. rerunning the program while
4154 it is already running. Default is ON.
4156 editing on/off: Enables EMACS style command line editing
4157 of input. Previous lines can be recalled with
4158 control-P, the current line can be edited with control-B,
4159 you can search for commands with control-R, etc.
4162 history filename NAME: NAME is where the gdb command history
4163 will be stored. The default is .gdb_history,
4164 or the value of the environment variable
4167 history size N: The size, in commands, of the command history. The
4168 default is 256, or the value of the environment variable
4171 history save on/off: If this value is set to ON, the history file will
4172 be saved after exiting gdb. If set to OFF, the
4173 file will not be saved. The default is OFF.
4175 history expansion on/off: If this value is set to ON, then csh-like
4176 history expansion will be performed on
4177 command line input. The default is OFF.
4179 radix N: Sets the default radix for input and output. It can be set
4180 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4181 in the current radix, so "set radix 10" is always a no-op.
4183 height N: This integer value is the number of lines on a page. Default
4184 is 24, the current `stty rows'' setting, or the ``li#''
4185 setting from the termcap entry matching the environment
4188 width N: This integer value is the number of characters on a line.
4189 Default is 80, the current `stty cols'' setting, or the ``co#''
4190 setting from the termcap entry matching the environment
4193 Note: ``set screensize'' is obsolete. Use ``set height'' and
4194 ``set width'' instead.
4196 print address on/off: Print memory addresses in various command displays,
4197 such as stack traces and structure values. Gdb looks
4198 more ``symbolic'' if you turn this off; it looks more
4199 ``machine level'' with it on. Default is ON.
4201 print array on/off: Prettyprint arrays. New convenient format! Default
4204 print demangle on/off: Print C++ symbols in "source" form if on,
4207 print asm-demangle on/off: Same, for assembler level printouts
4210 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4213 * Support for Epoch Environment.
4215 The epoch environment is a version of Emacs v18 with windowing. One
4216 new command, ``inspect'', is identical to ``print'', except that if you
4217 are running in the epoch environment, the value is printed in its own
4221 * Support for Shared Libraries
4223 GDB can now debug programs and core files that use SunOS shared libraries.
4224 Symbols from a shared library cannot be referenced
4225 before the shared library has been linked with the program (this
4226 happens after you type ``run'' and before the function main() is entered).
4227 At any time after this linking (including when examining core files
4228 from dynamically linked programs), gdb reads the symbols from each
4229 shared library when you type the ``sharedlibrary'' command.
4230 It can be abbreviated ``share''.
4232 sharedlibrary REGEXP: Load shared object library symbols for files
4233 matching a unix regular expression. No argument
4234 indicates to load symbols for all shared libraries.
4236 info sharedlibrary: Status of loaded shared libraries.
4241 A watchpoint stops execution of a program whenever the value of an
4242 expression changes. Checking for this slows down execution
4243 tremendously whenever you are in the scope of the expression, but is
4244 quite useful for catching tough ``bit-spreader'' or pointer misuse
4245 problems. Some machines such as the 386 have hardware for doing this
4246 more quickly, and future versions of gdb will use this hardware.
4248 watch EXP: Set a watchpoint (breakpoint) for an expression.
4250 info watchpoints: Information about your watchpoints.
4252 delete N: Deletes watchpoint number N (same as breakpoints).
4253 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4254 enable N: Re-enables watchpoint number N (same as breakpoints).
4257 * C++ multiple inheritance
4259 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4262 * C++ exception handling
4264 Gdb now supports limited C++ exception handling. Besides the existing
4265 ability to breakpoint on an exception handler, gdb can breakpoint on
4266 the raising of an exception (before the stack is peeled back to the
4269 catch FOO: If there is a FOO exception handler in the dynamic scope,
4270 set a breakpoint to catch exceptions which may be raised there.
4271 Multiple exceptions (``catch foo bar baz'') may be caught.
4273 info catch: Lists all exceptions which may be caught in the
4274 current stack frame.
4277 * Minor command changes
4279 The command ``call func (arg, arg, ...)'' now acts like the print
4280 command, except it does not print or save a value if the function's result
4281 is void. This is similar to dbx usage.
4283 The ``up'' and ``down'' commands now always print the frame they end up
4284 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4285 frames without printing.
4287 * New directory command
4289 'dir' now adds directories to the FRONT of the source search path.
4290 The path starts off empty. Source files that contain debug information
4291 about the directory in which they were compiled can be found even
4292 with an empty path; Sun CC and GCC include this information. If GDB can't
4293 find your source file in the current directory, type "dir .".
4295 * Configuring GDB for compilation
4297 For normal use, type ``./configure host''. See README or gdb.texinfo
4300 GDB now handles cross debugging. If you are remotely debugging between
4301 two different machines, type ``./configure host -target=targ''.
4302 Host is the machine where GDB will run; targ is the machine
4303 where the program that you are debugging will run.