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 * GDB now supports thread debugging of core dumps on GNU/Linux.
42 GDB now activates thread debugging using the libthread_db library
43 when debugging GNU/Linux core dumps, similarly to when debugging
44 live processes. As a result, when debugging a core dump file, GDB
45 is now able to display pthread_t ids of threads. For example, "info
46 threads" shows the same output as when debugging the process when it
47 was live. In earlier releases, you'd see something like this:
50 * 1 LWP 6780 main () at main.c:10
52 While now you see this:
55 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
57 It is also now possible to inspect TLS variables when debugging core
60 When debugging a core dump generated on a machine other than the one
61 used to run GDB, you may need to point GDB at the correct
62 libthread_db library with the "set libthread-db-search-path"
63 command. See the user manual for more details on this command.
65 * New features in the GDB remote stub, GDBserver
67 ** GDBserver is now supported on PowerPC LynxOS 4.x and 5.x.
69 *** Changes in GDB 7.2
71 * Shared library support for remote targets by default
73 When GDB is configured for a generic, non-OS specific target, like
74 for example, --target=arm-eabi or one of the many *-*-elf targets,
75 GDB now queries remote stubs for loaded shared libraries using the
76 `qXfer:libraries:read' packet. Previously, shared library support
77 was always disabled for such configurations.
81 ** Argument Dependent Lookup (ADL)
83 In C++ ADL lookup directs function search to the namespaces of its
84 arguments even if the namespace has not been imported.
94 Here the compiler will search for `foo' in the namespace of 'b'
95 and find A::foo. GDB now supports this. This construct is commonly
96 used in the Standard Template Library for operators.
98 ** Improved User Defined Operator Support
100 In addition to member operators, GDB now supports lookup of operators
101 defined in a namespace and imported with a `using' directive, operators
102 defined in the global scope, operators imported implicitly from an
103 anonymous namespace, and the ADL operators mentioned in the previous
105 GDB now also supports proper overload resolution for all the previously
106 mentioned flavors of operators.
108 ** static const class members
110 Printing of static const class members that are initialized in the
111 class definition has been fixed.
113 * Windows Thread Information Block access.
115 On Windows targets, GDB now supports displaying the Windows Thread
116 Information Block (TIB) structure. This structure is visible either
117 by using the new command `info w32 thread-information-block' or, by
118 dereferencing the new convenience variable named `$_tlb', a
119 thread-specific pointer to the TIB. This feature is also supported
120 when remote debugging using GDBserver.
124 Static tracepoints are calls in the user program into a tracing
125 library. One such library is a port of the LTTng kernel tracer to
126 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
127 When debugging with GDBserver, GDB now supports combining the GDB
128 tracepoint machinery with such libraries. For example: the user can
129 use GDB to probe a static tracepoint marker (a call from the user
130 program into the tracing library) with the new "strace" command (see
131 "New commands" below). This creates a "static tracepoint" in the
132 breakpoint list, that can be manipulated with the same feature set
133 as fast and regular tracepoints. E.g., collect registers, local and
134 global variables, collect trace state variables, and define
135 tracepoint conditions. In addition, the user can collect extra
136 static tracepoint marker specific data, by collecting the new
137 $_sdata internal variable. When analyzing the trace buffer, you can
138 inspect $_sdata like any other variable available to GDB. For more
139 information, see the "Tracepoints" chapter in GDB user manual. New
140 remote packets have been defined to support static tracepoints, see
141 the "New remote packets" section below.
143 * Better reconstruction of tracepoints after disconnected tracing
145 GDB will attempt to download the original source form of tracepoint
146 definitions when starting a trace run, and then will upload these
147 upon reconnection to the target, resulting in a more accurate
148 reconstruction of the tracepoints that are in use on the target.
152 You can now exercise direct control over the ways that GDB can
153 affect your program. For instance, you can disallow the setting of
154 breakpoints, so that the program can run continuously (assuming
155 non-stop mode). In addition, the "observer" variable is available
156 to switch all of the different controls; in observer mode, GDB
157 cannot affect the target's behavior at all, which is useful for
158 tasks like diagnosing live systems in the field.
160 * The new convenience variable $_thread holds the number of the
167 Return the address of the Windows Thread Information Block of a given thread.
171 In response to several of the tracepoint packets, the target may now
172 also respond with a number of intermediate `qRelocInsn' request
173 packets before the final result packet, to have GDB handle
174 relocating an instruction to execute at a different address. This
175 is particularly useful for stubs that support fast tracepoints. GDB
176 reports support for this feature in the qSupported packet.
180 List static tracepoint markers in the target program.
184 List static tracepoint markers at a given address in the target
187 qXfer:statictrace:read
189 Read the static trace data collected (by a `collect $_sdata'
190 tracepoint action). The remote stub reports support for this packet
191 to gdb's qSupported query.
195 Send the current settings of GDB's permission flags.
199 Send part of the source (textual) form of a tracepoint definition,
200 which includes location, conditional, and action list.
202 * The source command now accepts a -s option to force searching for the
203 script in the source search path even if the script name specifies
206 * New features in the GDB remote stub, GDBserver
208 - GDBserver now support tracepoints (including fast tracepoints, and
209 static tracepoints). The feature is currently supported by the
210 i386-linux and amd64-linux builds. See the "Tracepoints support
211 in gdbserver" section in the manual for more information.
213 GDBserver JIT compiles the tracepoint's conditional agent
214 expression bytecode into native code whenever possible for low
215 overhead dynamic tracepoints conditionals. For such tracepoints,
216 an expression that examines program state is evaluated when the
217 tracepoint is reached, in order to determine whether to capture
218 trace data. If the condition is simple and false, processing the
219 tracepoint finishes very quickly and no data is gathered.
221 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
222 for static tracepoints support.
224 - GDBserver now supports x86_64 Windows 64-bit debugging.
226 * GDB now sends xmlRegisters= in qSupported packet to indicate that
227 it understands register description.
229 * The --batch flag now disables pagination and queries.
231 * X86 general purpose registers
233 GDB now supports reading/writing byte, word and double-word x86
234 general purpose registers directly. This means you can use, say,
235 $ah or $ax to refer, respectively, to the byte register AH and
236 16-bit word register AX that are actually portions of the 32-bit
237 register EAX or 64-bit register RAX.
239 * The `commands' command now accepts a range of breakpoints to modify.
240 A plain `commands' following a command that creates multiple
241 breakpoints affects all the breakpoints set by that command. This
242 applies to breakpoints set by `rbreak', and also applies when a
243 single `break' command creates multiple breakpoints (e.g.,
244 breakpoints on overloaded c++ functions).
246 * The `rbreak' command now accepts a filename specification as part of
247 its argument, limiting the functions selected by the regex to those
248 in the specified file.
250 * Support for remote debugging Windows and SymbianOS shared libraries
251 from Unix hosts has been improved. Non Windows GDB builds now can
252 understand target reported file names that follow MS-DOS based file
253 system semantics, such as file names that include drive letters and
254 use the backslash character as directory separator. This makes it
255 possible to transparently use the "set sysroot" and "set
256 solib-search-path" on Unix hosts to point as host copies of the
257 target's shared libraries. See the new command "set
258 target-file-system-kind" described below, and the "Commands to
259 specify files" section in the user manual for more information.
263 eval template, expressions...
264 Convert the values of one or more expressions under the control
265 of the string template to a command line, and call it.
267 set target-file-system-kind unix|dos-based|auto
268 show target-file-system-kind
269 Set or show the assumed file system kind for target reported file
272 save breakpoints <filename>
273 Save all current breakpoint definitions to a file suitable for use
274 in a later debugging session. To read the saved breakpoint
275 definitions, use the `source' command.
277 `save tracepoints' is a new alias for `save-tracepoints'. The latter
280 info static-tracepoint-markers
281 Display information about static tracepoint markers in the target.
283 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
284 Define a static tracepoint by probing a marker at the given
285 function, line, address, or marker ID.
289 Enable and disable observer mode.
291 set may-write-registers on|off
292 set may-write-memory on|off
293 set may-insert-breakpoints on|off
294 set may-insert-tracepoints on|off
295 set may-insert-fast-tracepoints on|off
296 set may-interrupt on|off
297 Set individual permissions for GDB effects on the target. Note that
298 some of these settings can have undesirable or surprising
299 consequences, particularly when changed in the middle of a session.
300 For instance, disabling the writing of memory can prevent
301 breakpoints from being inserted, cause single-stepping to fail, or
302 even crash your program, if you disable after breakpoints have been
303 inserted. However, GDB should not crash.
305 set record memory-query on|off
306 show record memory-query
307 Control whether to stop the inferior if memory changes caused
308 by an instruction cannot be recorded.
313 The disassemble command now supports "start,+length" form of two arguments.
317 ** GDB now provides a new directory location, called the python directory,
318 where Python scripts written for GDB can be installed. The location
319 of that directory is <data-directory>/python, where <data-directory>
320 is the GDB data directory. For more details, see section `Scripting
321 GDB using Python' in the manual.
323 ** The GDB Python API now has access to breakpoints, symbols, symbol
324 tables, program spaces, inferiors, threads and frame's code blocks.
325 Additionally, GDB Parameters can now be created from the API, and
326 manipulated via set/show in the CLI.
328 ** New functions gdb.target_charset, gdb.target_wide_charset,
329 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
331 ** New exception gdb.GdbError.
333 ** Pretty-printers are now also looked up in the current program space.
335 ** Pretty-printers can now be individually enabled and disabled.
337 ** GDB now looks for names of Python scripts to auto-load in a
338 special section named `.debug_gdb_scripts', in addition to looking
339 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
341 * Tracepoint actions were unified with breakpoint commands. In particular,
342 there are no longer differences in "info break" output for breakpoints and
343 tracepoints and the "commands" command can be used for both tracepoints and
348 ARM Symbian arm*-*-symbianelf*
350 * D language support.
351 GDB now supports debugging programs written in the D programming
354 * GDB now supports the extended ptrace interface for PowerPC which is
355 available since Linux kernel version 2.6.34. This automatically enables
356 any hardware breakpoints and additional hardware watchpoints available in
357 the processor. The old ptrace interface exposes just one hardware
358 watchpoint and no hardware breakpoints.
360 * GDB is now able to use the Data Value Compare (DVC) register available on
361 embedded PowerPC processors to implement in hardware simple watchpoint
362 conditions of the form:
364 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
366 This works in native GDB running on Linux kernels with the extended ptrace
367 interface mentioned above.
369 *** Changes in GDB 7.1
375 GDB now supports importing of namespaces in C++. This enables the
376 user to inspect variables from imported namespaces. Support for
377 namepace aliasing has also been added. So, if a namespace is
378 aliased in the current scope (e.g. namepace C=A; ) the user can
379 print variables using the alias (e.g. (gdb) print C::x).
383 All known bugs relating to the printing of virtual base class were
384 fixed. It is now possible to call overloaded static methods using a
389 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
390 and reinterpret_cast<> are now handled by the C++ expression parser.
394 Xilinx MicroBlaze microblaze-*-*
399 Xilinx MicroBlaze microblaze
402 * Multi-program debugging.
404 GDB now has support for multi-program (a.k.a. multi-executable or
405 multi-exec) debugging. This allows for debugging multiple inferiors
406 simultaneously each running a different program under the same GDB
407 session. See "Debugging Multiple Inferiors and Programs" in the
408 manual for more information. This implied some user visible changes
409 in the multi-inferior support. For example, "info inferiors" now
410 lists inferiors that are not running yet or that have exited
411 already. See also "New commands" and "New options" below.
413 * New tracing features
415 GDB's tracepoint facility now includes several new features:
417 ** Trace state variables
419 GDB tracepoints now include support for trace state variables, which
420 are variables managed by the target agent during a tracing
421 experiment. They are useful for tracepoints that trigger each
422 other, so for instance one tracepoint can count hits in a variable,
423 and then a second tracepoint has a condition that is true when the
424 count reaches a particular value. Trace state variables share the
425 $-syntax of GDB convenience variables, and can appear in both
426 tracepoint actions and condition expressions. Use the "tvariable"
427 command to create, and "info tvariables" to view; see "Trace State
428 Variables" in the manual for more detail.
432 GDB now includes an option for defining fast tracepoints, which
433 targets may implement more efficiently, such as by installing a jump
434 into the target agent rather than a trap instruction. The resulting
435 speedup can be by two orders of magnitude or more, although the
436 tradeoff is that some program locations on some target architectures
437 might not allow fast tracepoint installation, for instance if the
438 instruction to be replaced is shorter than the jump. To request a
439 fast tracepoint, use the "ftrace" command, with syntax identical to
440 the regular trace command.
442 ** Disconnected tracing
444 It is now possible to detach GDB from the target while it is running
445 a trace experiment, then reconnect later to see how the experiment
446 is going. In addition, a new variable disconnected-tracing lets you
447 tell the target agent whether to continue running a trace if the
448 connection is lost unexpectedly.
452 GDB now has the ability to save the trace buffer into a file, and
453 then use that file as a target, similarly to you can do with
454 corefiles. You can select trace frames, print data that was
455 collected in them, and use tstatus to display the state of the
456 tracing run at the moment that it was saved. To create a trace
457 file, use "tsave <filename>", and to use it, do "target tfile
460 ** Circular trace buffer
462 You can ask the target agent to handle the trace buffer as a
463 circular buffer, discarding the oldest trace frames to make room for
464 newer ones, by setting circular-trace-buffer to on. This feature may
465 not be available for all target agents.
470 The disassemble command, when invoked with two arguments, now requires
471 the arguments to be comma-separated.
474 The info variables command now displays variable definitions. Files
475 which only declare a variable are not shown.
478 The source command is now capable of sourcing Python scripts.
479 This feature is dependent on the debugger being build with Python
482 Related to this enhancement is also the introduction of a new command
483 "set script-extension" (see below).
485 * New commands (for set/show, see "New options" below)
487 record save [<FILENAME>]
488 Save a file (in core file format) containing the process record
489 execution log for replay debugging at a later time.
491 record restore <FILENAME>
492 Restore the process record execution log that was saved at an
493 earlier time, for replay debugging.
495 add-inferior [-copies <N>] [-exec <FILENAME>]
498 clone-inferior [-copies <N>] [ID]
499 Make a new inferior ready to execute the same program another
505 maint info program-spaces
506 List the program spaces loaded into GDB.
508 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
509 show remote interrupt-sequence
510 Allow the user to select one of ^C, a BREAK signal or BREAK-g
511 as the sequence to the remote target in order to interrupt the execution.
512 Ctrl-C is a default. Some system prefers BREAK which is high level of
513 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
514 Magic SysRq g. It is BREAK signal and character 'g'.
516 set remote interrupt-on-connect [on | off]
517 show remote interrupt-on-connect
518 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
519 remote target when gdb connects to it. This is needed when you debug
522 set remotebreak [on | off]
524 Deprecated. Use "set/show remote interrupt-sequence" instead.
526 tvariable $NAME [ = EXP ]
527 Create or modify a trace state variable.
530 List trace state variables and their values.
532 delete tvariable $NAME ...
533 Delete one or more trace state variables.
536 Evaluate the given expressions without collecting anything into the
537 trace buffer. (Valid in tracepoint actions only.)
539 ftrace FN / FILE:LINE / *ADDR
540 Define a fast tracepoint at the given function, line, or address.
542 * New expression syntax
544 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
545 GDB now parses 0b101010 identically with 42.
549 set follow-exec-mode new|same
550 show follow-exec-mode
551 Control whether GDB reuses the same inferior across an exec call or
552 creates a new one. This is useful to be able to restart the old
553 executable after the inferior having done an exec call.
555 set default-collect EXPR, ...
557 Define a list of expressions to be collected at each tracepoint.
558 This is a useful way to ensure essential items are not overlooked,
559 such as registers or a critical global variable.
561 set disconnected-tracing
562 show disconnected-tracing
563 If set to 1, the target is instructed to continue tracing if it
564 loses its connection to GDB. If 0, the target is to stop tracing
567 set circular-trace-buffer
568 show circular-trace-buffer
569 If set to on, the target is instructed to use a circular trace buffer
570 and discard the oldest trace frames instead of stopping the trace due
571 to a full trace buffer. If set to off, the trace stops when the buffer
572 fills up. Some targets may not support this.
574 set script-extension off|soft|strict
575 show script-extension
576 If set to "off", the debugger does not perform any script language
577 recognition, and all sourced files are assumed to be GDB scripts.
578 If set to "soft" (the default), files are sourced according to
579 filename extension, falling back to GDB scripts if the first
581 If set to "strict", files are sourced according to filename extension.
583 set ada trust-PAD-over-XVS on|off
584 show ada trust-PAD-over-XVS
585 If off, activate a workaround against a bug in the debugging information
586 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
587 the GCC sources for more information about the GNAT encoding and
588 PAD types in particular). It is always safe to set this option to
589 off, but this introduces a slight performance penalty. The default
592 * Python API Improvements
594 ** GDB provides the new class gdb.LazyString. This is useful in
595 some pretty-printing cases. The new method gdb.Value.lazy_string
596 provides a simple way to create objects of this type.
598 ** The fields returned by gdb.Type.fields now have an
599 `is_base_class' attribute.
601 ** The new method gdb.Type.range returns the range of an array type.
603 ** The new method gdb.parse_and_eval can be used to parse and
604 evaluate an expression.
609 Define a trace state variable.
612 Get the current value of a trace state variable.
615 Set desired tracing behavior upon disconnection.
618 Set the trace buffer to be linear or circular.
621 Get data about the tracepoints currently in use.
625 Process record now works correctly with hardware watchpoints.
627 Multiple bug fixes have been made to the mips-irix port, making it
628 much more reliable. In particular:
629 - Debugging threaded applications is now possible again. Previously,
630 GDB would hang while starting the program, or while waiting for
631 the program to stop at a breakpoint.
632 - Attaching to a running process no longer hangs.
633 - An error occurring while loading a core file has been fixed.
634 - Changing the value of the PC register now works again. This fixes
635 problems observed when using the "jump" command, or when calling
636 a function from GDB, or even when assigning a new value to $pc.
637 - With the "finish" and "return" commands, the return value for functions
638 returning a small array is now correctly printed.
639 - It is now possible to break on shared library code which gets executed
640 during a shared library init phase (code executed while executing
641 their .init section). Previously, the breakpoint would have no effect.
642 - GDB is now able to backtrace through the signal handler for
643 non-threaded programs.
645 PIE (Position Independent Executable) programs debugging is now supported.
646 This includes debugging execution of PIC (Position Independent Code) shared
647 libraries although for that, it should be possible to run such libraries as an
650 *** Changes in GDB 7.0
652 * GDB now has an interface for JIT compilation. Applications that
653 dynamically generate code can create symbol files in memory and register
654 them with GDB. For users, the feature should work transparently, and
655 for JIT developers, the interface is documented in the GDB manual in the
656 "JIT Compilation Interface" chapter.
658 * Tracepoints may now be conditional. The syntax is as for
659 breakpoints; either an "if" clause appended to the "trace" command,
660 or the "condition" command is available. GDB sends the condition to
661 the target for evaluation using the same bytecode format as is used
662 for tracepoint actions.
664 * The disassemble command now supports: an optional /r modifier, print the
665 raw instructions in hex as well as in symbolic form, and an optional /m
666 modifier to print mixed source+assembly.
668 * Process record and replay
670 In a architecture environment that supports ``process record and
671 replay'', ``process record and replay'' target can record a log of
672 the process execution, and replay it with both forward and reverse
675 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
676 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
677 set execution-direction {forward|reverse}, for targets that support
680 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
681 feature is available with a native GDB running on kernel version
684 * GDB now has support for multi-byte and wide character sets on the
685 target. Strings whose character type is wchar_t, char16_t, or
686 char32_t are now correctly printed. GDB supports wide- and unicode-
687 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
688 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
689 `printf'. This feature requires iconv to work properly; if your
690 system does not have a working iconv, GDB can use GNU libiconv. See
691 the installation instructions for more information.
693 * GDB now supports automatic retrieval of shared library files from
694 remote targets. To use this feature, specify a system root that begins
695 with the `remote:' prefix, either via the `set sysroot' command or via
696 the `--with-sysroot' configure-time option.
698 * "info sharedlibrary" now takes an optional regex of libraries to show,
699 and it now reports if a shared library has no debugging information.
701 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
702 now complete on file names.
704 * When completing in expressions, gdb will attempt to limit
705 completions to allowable structure or union fields, where appropriate.
706 For instance, consider:
708 # struct example { int f1; double f2; };
709 # struct example variable;
712 If the user types TAB at the end of this command line, the available
713 completions will be "f1" and "f2".
715 * Inlined functions are now supported. They show up in backtraces, and
716 the "step", "next", and "finish" commands handle them automatically.
718 * GDB now supports the token-splicing (##) and stringification (#)
719 operators when expanding macros. It also supports variable-arity
722 * GDB now supports inspecting extra signal information, exported by
723 the new $_siginfo convenience variable. The feature is currently
724 implemented on linux ARM, i386 and amd64.
726 * GDB can now display the VFP floating point registers and NEON vector
727 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
728 can provide these registers (requires Linux 2.6.30 or later). Remote
729 and simulator targets may also provide them.
734 Search memory for a sequence of bytes.
737 Turn off `+'/`-' protocol acknowledgments to permit more efficient
738 operation over reliable transport links. Use of this packet is
739 controlled by the `set remote noack-packet' command.
742 Kill the process with the specified process ID. Use this in preference
743 to `k' when multiprocess protocol extensions are supported.
746 Obtains additional operating system information
750 Read or write additional signal information.
752 * Removed remote protocol undocumented extension
754 An undocumented extension to the remote protocol's `S' stop reply
755 packet that permited the stub to pass a process id was removed.
756 Remote servers should use the `T' stop reply packet instead.
758 * GDB now supports multiple function calling conventions according to the
759 DWARF-2 DW_AT_calling_convention function attribute.
761 * The SH target utilizes the aforementioned change to distinguish between gcc
762 and Renesas calling convention. It also adds the new CLI commands
763 `set/show sh calling-convention'.
765 * GDB can now read compressed debug sections, as produced by GNU gold
766 with the --compress-debug-sections=zlib flag.
768 * 64-bit core files are now supported on AIX.
770 * Thread switching is now supported on Tru64.
772 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
773 which will be allocated using malloc later in program execution.
775 * The qXfer:libraries:read remote procotol packet now allows passing a
776 list of section offsets.
778 * On GNU/Linux, GDB can now attach to stopped processes. Several race
779 conditions handling signals delivered during attach or thread creation
780 have also been fixed.
782 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
783 From the user's standpoint, all unqualified instances of True and False
784 are treated as the standard definitions, regardless of context.
786 * GDB now parses C++ symbol and type names more flexibly. For
789 template<typename T> class C { };
792 GDB will now correctly handle all of:
794 ptype C<char const *>
796 ptype C<const char *>
799 * New features in the GDB remote stub, gdbserver
801 - The "--wrapper" command-line argument tells gdbserver to use a
802 wrapper program to launch programs for debugging.
804 - On PowerPC and S/390 targets, it is now possible to use a single
805 gdbserver executable to debug both 32-bit and 64-bit programs.
806 (This requires gdbserver itself to be built as a 64-bit executable.)
808 - gdbserver uses the new noack protocol mode for TCP connections to
809 reduce communications latency, if also supported and enabled in GDB.
811 - Support for the sparc64-linux-gnu target is now included in
814 - The amd64-linux build of gdbserver now supports debugging both
815 32-bit and 64-bit programs.
817 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
818 now support hardware watchpoints, and will use them automatically
823 GDB now has support for scripting using Python. Whether this is
824 available is determined at configure time.
826 New GDB commands can now be written in Python.
828 * Ada tasking support
830 Ada tasks can now be inspected in GDB. The following commands have
834 Print the list of Ada tasks.
836 Print detailed information about task number N.
838 Print the task number of the current task.
840 Switch the context of debugging to task number N.
842 * Support for user-defined prefixed commands. The "define" command can
843 add new commands to existing prefixes, e.g. "target".
845 * Multi-inferior, multi-process debugging.
847 GDB now has generalized support for multi-inferior debugging. See
848 "Debugging Multiple Inferiors" in the manual for more information.
849 Although availability still depends on target support, the command
850 set is more uniform now. The GNU/Linux specific multi-forks support
851 has been migrated to this new framework. This implied some user
852 visible changes; see "New commands" and also "Removed commands"
855 * Target descriptions can now describe the target OS ABI. See the
856 "Target Description Format" section in the user manual for more
859 * Target descriptions can now describe "compatible" architectures
860 to indicate that the target can execute applications for a different
861 architecture in addition to those for the main target architecture.
862 See the "Target Description Format" section in the user manual for
865 * Multi-architecture debugging.
867 GDB now includes general supports for debugging applications on
868 hybrid systems that use more than one single processor architecture
869 at the same time. Each such hybrid architecture still requires
870 specific support to be added. The only hybrid architecture supported
871 in this version of GDB is the Cell Broadband Engine.
873 * GDB now supports integrated debugging of Cell/B.E. applications that
874 use both the PPU and SPU architectures. To enable support for hybrid
875 Cell/B.E. debugging, you need to configure GDB to support both the
876 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
877 --enable-targets configure option.
879 * Non-stop mode debugging.
881 For some targets, GDB now supports an optional mode of operation in
882 which you can examine stopped threads while other threads continue
883 to execute freely. This is referred to as non-stop mode, with the
884 old mode referred to as all-stop mode. See the "Non-Stop Mode"
885 section in the user manual for more information.
887 To be able to support remote non-stop debugging, a remote stub needs
888 to implement the non-stop mode remote protocol extensions, as
889 described in the "Remote Non-Stop" section of the user manual. The
890 GDB remote stub, gdbserver, has been adjusted to support these
891 extensions on linux targets.
893 * New commands (for set/show, see "New options" below)
895 catch syscall [NAME(S) | NUMBER(S)]
896 Catch system calls. Arguments, which should be names of system
897 calls or their numbers, mean catch only those syscalls. Without
898 arguments, every syscall will be caught. When the inferior issues
899 any of the specified syscalls, GDB will stop and announce the system
900 call, both when it is called and when its call returns. This
901 feature is currently available with a native GDB running on the
902 Linux Kernel, under the following architectures: x86, x86_64,
903 PowerPC and PowerPC64.
905 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
907 Search memory for a sequence of bytes.
909 maint set python print-stack
910 maint show python print-stack
911 Show a stack trace when an error is encountered in a Python script.
914 Invoke CODE by passing it to the Python interpreter.
919 These allow macros to be defined, undefined, and listed
923 Show operating system information about processes.
926 List the inferiors currently under GDB's control.
929 Switch focus to inferior number NUM.
932 Detach from inferior number NUM.
935 Kill inferior number NUM.
940 show spu stop-on-load
941 Control whether to stop for new SPE threads during Cell/B.E. debugging.
943 set spu auto-flush-cache
944 show spu auto-flush-cache
945 Control whether to automatically flush the software-managed cache
946 during Cell/B.E. debugging.
948 set sh calling-convention
949 show sh calling-convention
950 Control the calling convention used when calling SH target functions.
954 Control display of timestamps with GDB debugging output.
956 set disassemble-next-line
957 show disassemble-next-line
958 Control display of disassembled source lines or instructions when
961 set remote noack-packet
962 show remote noack-packet
963 Set/show the use of remote protocol QStartNoAckMode packet. See above
964 under "New remote packets."
966 set remote query-attached-packet
967 show remote query-attached-packet
968 Control use of remote protocol `qAttached' (query-attached) packet.
970 set remote read-siginfo-object
971 show remote read-siginfo-object
972 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
975 set remote write-siginfo-object
976 show remote write-siginfo-object
977 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
980 set remote reverse-continue
981 show remote reverse-continue
982 Control use of remote protocol 'bc' (reverse-continue) packet.
984 set remote reverse-step
985 show remote reverse-step
986 Control use of remote protocol 'bs' (reverse-step) packet.
988 set displaced-stepping
989 show displaced-stepping
990 Control displaced stepping mode. Displaced stepping is a way to
991 single-step over breakpoints without removing them from the debuggee.
992 Also known as "out-of-line single-stepping".
996 Control display of debugging info for displaced stepping.
998 maint set internal-error
999 maint show internal-error
1000 Control what GDB does when an internal error is detected.
1002 maint set internal-warning
1003 maint show internal-warning
1004 Control what GDB does when an internal warning is detected.
1009 Use a wrapper program to launch programs for debugging.
1011 set multiple-symbols (all|ask|cancel)
1012 show multiple-symbols
1013 The value of this variable can be changed to adjust the debugger behavior
1014 when an expression or a breakpoint location contains an ambiguous symbol
1015 name (an overloaded function name, for instance).
1017 set breakpoint always-inserted
1018 show breakpoint always-inserted
1019 Keep breakpoints always inserted in the target, as opposed to inserting
1020 them when resuming the target, and removing them when the target stops.
1021 This option can improve debugger performance on slow remote targets.
1023 set arm fallback-mode (arm|thumb|auto)
1024 show arm fallback-mode
1025 set arm force-mode (arm|thumb|auto)
1027 These commands control how ARM GDB determines whether instructions
1028 are ARM or Thumb. The default for both settings is auto, which uses
1029 the current CPSR value for instructions without symbols; previous
1030 versions of GDB behaved as if "set arm fallback-mode arm".
1032 set disable-randomization
1033 show disable-randomization
1034 Standalone programs run with the virtual address space randomization enabled
1035 by default on some platforms. This option keeps the addresses stable across
1036 multiple debugging sessions.
1040 Control whether other threads are stopped or not when some thread hits
1045 Requests that asynchronous execution is enabled in the target, if available.
1046 In this case, it's possible to resume target in the background, and interact
1047 with GDB while the target is running. "show target-async" displays the
1048 current state of asynchronous execution of the target.
1050 set target-wide-charset
1051 show target-wide-charset
1052 The target-wide-charset is the name of the character set that GDB
1053 uses when printing characters whose type is wchar_t.
1055 set tcp auto-retry (on|off)
1057 set tcp connect-timeout
1058 show tcp connect-timeout
1059 These commands allow GDB to retry failed TCP connections to a remote stub
1060 with a specified timeout period; this is useful if the stub is launched
1061 in parallel with GDB but may not be ready to accept connections immediately.
1063 set libthread-db-search-path
1064 show libthread-db-search-path
1065 Control list of directories which GDB will search for appropriate
1068 set schedule-multiple (on|off)
1069 show schedule-multiple
1070 Allow GDB to resume all threads of all processes or only threads of
1071 the current process.
1075 Use more aggressive caching for accesses to the stack. This improves
1076 performance of remote debugging (particularly backtraces) without
1077 affecting correctness.
1079 set interactive-mode (on|off|auto)
1080 show interactive-mode
1081 Control whether GDB runs in interactive mode (on) or not (off).
1082 When in interactive mode, GDB waits for the user to answer all
1083 queries. Otherwise, GDB does not wait and assumes the default
1084 answer. When set to auto (the default), GDB determines which
1085 mode to use based on the stdin settings.
1090 For program forks, this is replaced by the new more generic `info
1091 inferiors' command. To list checkpoints, you can still use the
1092 `info checkpoints' command, which was an alias for the `info forks'
1096 Replaced by the new `inferior' command. To switch between
1097 checkpoints, you can still use the `restart' command, which was an
1098 alias for the `fork' command.
1101 This is removed, since some targets don't have a notion of
1102 processes. To switch between processes, you can still use the
1103 `inferior' command using GDB's own inferior number.
1106 For program forks, this is replaced by the new more generic `kill
1107 inferior' command. To delete a checkpoint, you can still use the
1108 `delete checkpoint' command, which was an alias for the `delete
1112 For program forks, this is replaced by the new more generic `detach
1113 inferior' command. To detach a checkpoint, you can still use the
1114 `detach checkpoint' command, which was an alias for the `detach
1117 * New native configurations
1119 x86/x86_64 Darwin i[34567]86-*-darwin*
1121 x86_64 MinGW x86_64-*-mingw*
1125 Lattice Mico32 lm32-*
1126 x86 DICOS i[34567]86-*-dicos*
1127 x86_64 DICOS x86_64-*-dicos*
1130 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1131 (mingw32ce) debugging.
1137 These commands were actually not implemented on any target.
1139 *** Changes in GDB 6.8
1141 * New native configurations
1143 NetBSD/hppa hppa*-*netbsd*
1144 Xtensa GNU/Linux xtensa*-*-linux*
1148 NetBSD/hppa hppa*-*-netbsd*
1149 Xtensa GNU/Lunux xtensa*-*-linux*
1151 * Change in command line behavior -- corefiles vs. process ids.
1153 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1154 attaching to process NUMBER fails, GDB no longer attempts to open a
1155 core file named NUMBER. Attaching to a program using the -c option
1156 is no longer supported. Instead, use the '-p' or '--pid' options.
1158 * GDB can now be built as a native debugger for debugging Windows x86
1159 (mingw32) Portable Executable (PE) programs.
1161 * Pending breakpoints no longer change their number when their address
1164 * GDB now supports breakpoints with multiple locations,
1165 including breakpoints on C++ constructors, inside C++ templates,
1166 and in inlined functions.
1168 * GDB's ability to debug optimized code has been improved. GDB more
1169 accurately identifies function bodies and lexical blocks that occupy
1170 more than one contiguous range of addresses.
1172 * Target descriptions can now describe registers for PowerPC.
1174 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1175 registers on PowerPC targets.
1177 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1178 targets even when the libthread_db library is not available.
1180 * The GDB remote stub, gdbserver, now supports the new file transfer
1181 commands (remote put, remote get, and remote delete).
1183 * The GDB remote stub, gdbserver, now supports run and attach in
1184 extended-remote mode.
1186 * hppa*64*-*-hpux11* target broken
1187 The debugger is unable to start a program and fails with the following
1188 error: "Error trying to get information about dynamic linker".
1189 The gdb-6.7 release is also affected.
1191 * GDB now supports the --enable-targets= configure option to allow
1192 building a single GDB executable that supports multiple remote
1193 target architectures.
1195 * GDB now supports debugging C and C++ programs which use the
1196 Decimal Floating Point extension. In addition, the PowerPC target
1197 now has a set of pseudo-registers to inspect decimal float values
1198 stored in two consecutive float registers.
1200 * The -break-insert MI command can optionally create pending
1203 * Improved support for debugging Ada
1204 Many improvements to the Ada language support have been made. These
1206 - Better support for Ada2005 interface types
1207 - Improved handling of arrays and slices in general
1208 - Better support for Taft-amendment types
1209 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1211 - Improved command completion in Ada
1214 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1219 set print frame-arguments (all|scalars|none)
1220 show print frame-arguments
1221 The value of this variable can be changed to control which argument
1222 values should be printed by the debugger when displaying a frame.
1227 Transfer files to and from a remote target, and delete remote files.
1234 Transfer files to and from a remote target, and delete remote files.
1236 * New remote packets
1243 Open, close, read, write, and delete files on the remote system.
1246 Attach to an existing process on the remote system, in extended-remote
1250 Run a new process on the remote system, in extended-remote mode.
1252 *** Changes in GDB 6.7
1254 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1255 bfd, libiberty and opcodes, as revealed by static analysis donated by
1256 Coverity, Inc. (http://scan.coverity.com).
1258 * When looking up multiply-defined global symbols, GDB will now prefer the
1259 symbol definition in the current shared library if it was built using the
1260 -Bsymbolic linker option.
1262 * When the Text User Interface (TUI) is not configured, GDB will now
1263 recognize the -tui command-line option and print a message that the TUI
1266 * The GDB remote stub, gdbserver, now has lower overhead for high
1267 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1269 * GDB for MIPS targets now autodetects whether a remote target provides
1270 32-bit or 64-bit register values.
1272 * Support for C++ member pointers has been improved.
1274 * GDB now understands XML target descriptions, which specify the
1275 target's overall architecture. GDB can read a description from
1276 a local file or over the remote serial protocol.
1278 * Vectors of single-byte data use a new integer type which is not
1279 automatically displayed as character or string data.
1281 * The /s format now works with the print command. It displays
1282 arrays of single-byte integers and pointers to single-byte integers
1285 * Target descriptions can now describe target-specific registers,
1286 for architectures which have implemented the support (currently
1287 only ARM, M68K, and MIPS).
1289 * GDB and the GDB remote stub, gdbserver, now support the XScale
1292 * The GDB remote stub, gdbserver, has been updated to support
1293 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1294 has been rewritten to use the standard GDB remote protocol.
1296 * GDB can now step into C++ functions which are called through thunks.
1298 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1300 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1301 layout. It also supports a TextSeg= and DataSeg= response when only
1302 segment base addresses (rather than offsets) are available.
1304 * The /i format now outputs any trailing branch delay slot instructions
1305 immediately following the last instruction within the count specified.
1307 * The GDB remote protocol "T" stop reply packet now supports a
1308 "library" response. Combined with the new "qXfer:libraries:read"
1309 packet, this response allows GDB to debug shared libraries on targets
1310 where the operating system manages the list of loaded libraries (e.g.
1311 Windows and SymbianOS).
1313 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1314 (DLLs) on Windows and Windows CE targets.
1316 * GDB now supports a faster verification that a .debug file matches its binary
1317 according to its build-id signature, if the signature is present.
1323 Enable or disable hardware flow control (RTS/CTS) on the serial port
1324 when debugging using remote targets.
1326 set mem inaccessible-by-default
1327 show mem inaccessible-by-default
1328 If the target supplies a memory map, for instance via the remote
1329 protocol's "qXfer:memory-map:read" packet, setting this variable
1330 prevents GDB from accessing memory outside the memory map. This
1331 is useful for targets with memory mapped registers or which react
1332 badly to accesses of unmapped address space.
1334 set breakpoint auto-hw
1335 show breakpoint auto-hw
1336 If the target supplies a memory map, for instance via the remote
1337 protocol's "qXfer:memory-map:read" packet, setting this variable
1338 lets GDB use hardware breakpoints automatically for memory regions
1339 where it can not use software breakpoints. This covers both the
1340 "break" command and internal breakpoints used for other commands
1341 including "next" and "finish".
1344 catch exception unhandled
1345 Stop the program execution when Ada exceptions are raised.
1348 Stop the program execution when an Ada assertion failed.
1352 Set an alternate system root for target files. This is a more
1353 general version of "set solib-absolute-prefix", which is now
1354 an alias to "set sysroot".
1357 Provide extended SPU facility status information. This set of
1358 commands is available only when debugging the Cell/B.E. SPU
1361 * New native configurations
1363 OpenBSD/sh sh*-*openbsd*
1366 unset tdesc filename
1368 Use the specified local file as an XML target description, and do
1369 not query the target for its built-in description.
1373 OpenBSD/sh sh*-*-openbsd*
1374 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1375 Toshiba Media Processor mep-elf
1377 * New remote packets
1380 Ignore the specified signals; pass them directly to the debugged program
1381 without stopping other threads or reporting them to GDB.
1383 qXfer:features:read:
1384 Read an XML target description from the target, which describes its
1389 Read or write contents of an spufs file on the target system. These
1390 packets are available only on the Cell/B.E. SPU architecture.
1392 qXfer:libraries:read:
1393 Report the loaded shared libraries. Combined with new "T" packet
1394 response, this packet allows GDB to debug shared libraries on
1395 targets where the operating system manages the list of loaded
1396 libraries (e.g. Windows and SymbianOS).
1400 Support for these obsolete configurations has been removed.
1408 i[34567]86-*-lynxos*
1409 i[34567]86-*-netware*
1410 i[34567]86-*-sco3.2v5*
1411 i[34567]86-*-sco3.2v4*
1413 i[34567]86-*-sysv4.2*
1416 i[34567]86-*-unixware2*
1417 i[34567]86-*-unixware*
1426 * Other removed features
1433 Various m68k-only ROM monitors.
1440 Various Renesas ROM monitors and debugging interfaces for SH and
1445 Support for a Macraigor serial interface to on-chip debugging.
1446 GDB does not directly support the newer parallel or USB
1451 A debug information format. The predecessor to DWARF 2 and
1452 DWARF 3, which are still supported.
1454 Support for the HP aCC compiler on HP-UX/PA-RISC
1456 SOM-encapsulated symbolic debugging information, automatic
1457 invocation of pxdb, and the aCC custom C++ ABI. This does not
1458 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1459 with aCC can still be debugged on an assembly level.
1461 MIPS ".pdr" sections
1463 A MIPS-specific format used to describe stack frame layout
1464 in debugging information.
1468 GDB could work with an older version of Guile to debug
1469 the interpreter and Scheme programs running in it.
1471 set mips stack-arg-size
1472 set mips saved-gpreg-size
1474 Use "set mips abi" to control parameter passing for MIPS.
1476 *** Changes in GDB 6.6
1481 Cell Broadband Engine SPU spu-elf
1483 * GDB can now be configured as a cross-debugger targeting native Windows
1484 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1485 running on a Windows system over TCP/IP to debug Windows programs.
1487 * The GDB remote stub, gdbserver, has been updated to support Windows and
1488 Cygwin debugging. Both single-threaded and multi-threaded programs are
1491 * The "set trust-readonly-sections" command works again. This command was
1492 broken in GDB 6.3, 6.4, and 6.5.
1494 * The "load" command now supports writing to flash memory, if the remote
1495 stub provides the required support.
1497 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1498 longer requires symbolic debug information (e.g. DWARF-2).
1503 unset substitute-path
1504 show substitute-path
1505 Manage a list of substitution rules that GDB uses to rewrite the name
1506 of the directories where the sources are located. This can be useful
1507 for instance when the sources were moved to a different location
1508 between compilation and debugging.
1512 Print each CLI command as it is executed. Each command is prefixed with
1513 a number of `+' symbols representing the nesting depth.
1514 The source command now has a `-v' option to enable the same feature.
1518 The ARM Demon monitor support (RDP protocol, "target rdp").
1520 Kernel Object Display, an embedded debugging feature which only worked with
1521 an obsolete version of Cisco IOS.
1523 The 'set download-write-size' and 'show download-write-size' commands.
1525 * New remote packets
1528 Tell a stub about GDB client features, and request remote target features.
1529 The first feature implemented is PacketSize, which allows the target to
1530 specify the size of packets it can handle - to minimize the number of
1531 packets required and improve performance when connected to a remote
1535 Fetch an OS auxilliary vector from the remote stub. This packet is a
1536 more efficient replacement for qPart:auxv:read.
1538 qXfer:memory-map:read:
1539 Fetch a memory map from the remote stub, including information about
1540 RAM, ROM, and flash memory devices.
1545 Erase and program a flash memory device.
1547 * Removed remote packets
1550 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1551 used it, and only gdbserver implemented it.
1553 *** Changes in GDB 6.5
1557 Renesas M32C/M16C m32c-elf
1559 Morpho Technologies ms1 ms1-elf
1563 init-if-undefined Initialize a convenience variable, but
1564 only if it doesn't already have a value.
1566 The following commands are presently only implemented for native GNU/Linux:
1568 checkpoint Save a snapshot of the program state.
1570 restart <n> Return the program state to a
1571 previously saved state.
1573 info checkpoints List currently saved checkpoints.
1575 delete-checkpoint <n> Delete a previously saved checkpoint.
1577 set|show detach-on-fork Tell gdb whether to detach from a newly
1578 forked process, or to keep debugging it.
1580 info forks List forks of the user program that
1581 are available to be debugged.
1583 fork <n> Switch to debugging one of several
1584 forks of the user program that are
1585 available to be debugged.
1587 delete-fork <n> Delete a fork from the list of forks
1588 that are available to be debugged (and
1589 kill the forked process).
1591 detach-fork <n> Delete a fork from the list of forks
1592 that are available to be debugged (and
1593 allow the process to continue).
1597 Morpho Technologies ms2 ms1-elf
1599 * Improved Windows host support
1601 GDB now builds as a cross debugger hosted on i686-mingw32, including
1602 native console support, and remote communications using either
1603 network sockets or serial ports.
1605 * Improved Modula-2 language support
1607 GDB can now print most types in the Modula-2 syntax. This includes:
1608 basic types, set types, record types, enumerated types, range types,
1609 pointer types and ARRAY types. Procedure var parameters are correctly
1610 printed and hexadecimal addresses and character constants are also
1611 written in the Modula-2 syntax. Best results can be obtained by using
1612 GNU Modula-2 together with the -gdwarf-2 command line option.
1616 The ARM rdi-share module.
1618 The Netware NLM debug server.
1620 *** Changes in GDB 6.4
1622 * New native configurations
1624 OpenBSD/arm arm*-*-openbsd*
1625 OpenBSD/mips64 mips64-*-openbsd*
1629 Morpho Technologies ms1 ms1-elf
1631 * New command line options
1633 --batch-silent As for --batch, but totally silent.
1634 --return-child-result The debugger will exist with the same value
1635 the child (debugged) program exited with.
1636 --eval-command COMMAND, -ex COMMAND
1637 Execute a single GDB CLI command. This may be
1638 specified multiple times and in conjunction
1639 with the --command (-x) option.
1641 * Deprecated commands removed
1643 The following commands, that were deprecated in 2000, have been
1647 set|show arm disassembly-flavor set|show arm disassembler
1648 othernames set arm disassembler
1649 set|show remotedebug set|show debug remote
1650 set|show archdebug set|show debug arch
1651 set|show eventdebug set|show debug event
1654 * New BSD user-level threads support
1656 It is now possible to debug programs using the user-level threads
1657 library on OpenBSD and FreeBSD. Currently supported (target)
1660 FreeBSD/amd64 x86_64-*-freebsd*
1661 FreeBSD/i386 i386-*-freebsd*
1662 OpenBSD/i386 i386-*-openbsd*
1664 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1665 are not yet supported.
1667 * New support for Matsushita MN10300 w/sim added
1668 (Work in progress). mn10300-elf.
1670 * REMOVED configurations and files
1672 VxWorks and the XDR protocol *-*-vxworks
1673 Motorola MCORE mcore-*-*
1674 National Semiconductor NS32000 ns32k-*-*
1676 * New "set print array-indexes" command
1678 After turning this setting "on", GDB prints the index of each element
1679 when displaying arrays. The default is "off" to preserve the previous
1682 * VAX floating point support
1684 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1686 * User-defined command support
1688 In addition to using $arg0..$arg9 for argument passing, it is now possible
1689 to use $argc to determine now many arguments have been passed. See the
1690 section on user-defined commands in the user manual for more information.
1692 *** Changes in GDB 6.3:
1694 * New command line option
1696 GDB now accepts -l followed by a number to set the timeout for remote
1699 * GDB works with GCC -feliminate-dwarf2-dups
1701 GDB now supports a more compact representation of DWARF-2 debug
1702 information using DW_FORM_ref_addr references. These are produced
1703 by GCC with the option -feliminate-dwarf2-dups and also by some
1704 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1705 to use -feliminate-dwarf2-dups.
1707 * Internationalization
1709 When supported by the host system, GDB will be built with
1710 internationalization (libintl). The task of marking up the sources is
1711 continued, we're looking forward to our first translation.
1715 Initial support for debugging programs compiled with the GNAT
1716 implementation of the Ada programming language has been integrated
1717 into GDB. In this release, support is limited to expression evaluation.
1719 * New native configurations
1721 GNU/Linux/m32r m32r-*-linux-gnu
1725 GDB's remote protocol now includes support for the 'p' packet. This
1726 packet is used to fetch individual registers from a remote inferior.
1728 * END-OF-LIFE registers[] compatibility module
1730 GDB's internal register infrastructure has been completely rewritten.
1731 The new infrastructure making possible the implementation of key new
1732 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1735 GDB 6.3 will be the last release to include the the registers[]
1736 compatibility module that allowed out-of-date configurations to
1737 continue to work. This change directly impacts the following
1747 powerpc bdm protocol
1749 Unless there is activity to revive these configurations, they will be
1750 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1752 * OBSOLETE configurations and files
1754 Configurations that have been declared obsolete in this release have
1755 been commented out. Unless there is activity to revive these
1756 configurations, the next release of GDB will have their sources
1757 permanently REMOVED.
1766 *** Changes in GDB 6.2.1:
1768 * MIPS `break main; run' gave an heuristic-fence-post warning
1770 When attempting to run even a simple program, a warning about
1771 heuristic-fence-post being hit would be reported. This problem has
1774 * MIPS IRIX 'long double' crashed GDB
1776 When examining a long double variable, GDB would get a segmentation
1777 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1778 IRIX long double values).
1782 A bug in the VAX stack code was causing problems with the "next"
1783 command. This problem has been fixed.
1785 *** Changes in GDB 6.2:
1787 * Fix for ``many threads''
1789 On GNU/Linux systems that use the NPTL threads library, a program
1790 rapidly creating and deleting threads would confuse GDB leading to the
1793 ptrace: No such process.
1794 thread_db_get_info: cannot get thread info: generic error
1796 This problem has been fixed.
1798 * "-async" and "-noasync" options removed.
1800 Support for the broken "-noasync" option has been removed (it caused
1803 * New ``start'' command.
1805 This command runs the program until the begining of the main procedure.
1807 * New BSD Kernel Data Access Library (libkvm) interface
1809 Using ``target kvm'' it is now possible to debug kernel core dumps and
1810 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1811 platforms. Currently supported (native-only) configurations are:
1813 FreeBSD/amd64 x86_64-*-freebsd*
1814 FreeBSD/i386 i?86-*-freebsd*
1815 NetBSD/i386 i?86-*-netbsd*
1816 NetBSD/m68k m68*-*-netbsd*
1817 NetBSD/sparc sparc-*-netbsd*
1818 OpenBSD/amd64 x86_64-*-openbsd*
1819 OpenBSD/i386 i?86-*-openbsd*
1820 OpenBSD/m68k m68*-openbsd*
1821 OpenBSD/sparc sparc-*-openbsd*
1823 * Signal trampoline code overhauled
1825 Many generic problems with GDB's signal handling code have been fixed.
1826 These include: backtraces through non-contiguous stacks; recognition
1827 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1828 call; backtrace through a signal trampoline; step into and out of
1829 signal handlers; and single-stepping in the signal trampoline.
1831 Please note that kernel bugs are a limiting factor here. These
1832 features have been shown to work on an s390 GNU/Linux system that
1833 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1835 * Cygwin support for DWARF 2 added.
1837 * New native configurations
1839 GNU/Linux/hppa hppa*-*-linux*
1840 OpenBSD/hppa hppa*-*-openbsd*
1841 OpenBSD/m68k m68*-*-openbsd*
1842 OpenBSD/m88k m88*-*-openbsd*
1843 OpenBSD/powerpc powerpc-*-openbsd*
1844 NetBSD/vax vax-*-netbsd*
1845 OpenBSD/vax vax-*-openbsd*
1847 * END-OF-LIFE frame compatibility module
1849 GDB's internal frame infrastructure has been completely rewritten.
1850 The new infrastructure making it possible to support key new features
1851 including DWARF 2 Call Frame Information. To aid in the task of
1852 migrating old configurations to this new infrastructure, a
1853 compatibility module, that allowed old configurations to continue to
1854 work, was also included.
1856 GDB 6.2 will be the last release to include this frame compatibility
1857 module. This change directly impacts the following configurations:
1867 Unless there is activity to revive these configurations, they will be
1868 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1870 * REMOVED configurations and files
1872 Sun 3, running SunOS 3 m68*-*-sunos3*
1873 Sun 3, running SunOS 4 m68*-*-sunos4*
1874 Sun 2, running SunOS 3 m68000-*-sunos3*
1875 Sun 2, running SunOS 4 m68000-*-sunos4*
1876 Motorola 680x0 running LynxOS m68*-*-lynxos*
1877 AT&T 3b1/Unix pc m68*-att-*
1878 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1879 decstation mips-dec-* mips-little-*
1880 riscos mips-*-riscos* mips-*-sysv*
1881 sonymips mips-sony-*
1882 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1884 *** Changes in GDB 6.1.1:
1886 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1888 The TUI (Text-mode User Interface) is now built as part of a default
1889 GDB configuration. It is enabled by either selecting the TUI with the
1890 command line option "-i=tui" or by running the separate "gdbtui"
1891 program. For more information on the TUI, see the manual "Debugging
1894 * Pending breakpoint support (also included in GDB 6.1)
1896 Support has been added to allow you to specify breakpoints in shared
1897 libraries that have not yet been loaded. If a breakpoint location
1898 cannot be found, and the "breakpoint pending" option is set to auto,
1899 GDB queries you if you wish to make the breakpoint pending on a future
1900 shared-library load. If and when GDB resolves the breakpoint symbol,
1901 the pending breakpoint is removed as one or more regular breakpoints
1904 Pending breakpoints are very useful for GCJ Java debugging.
1906 * Fixed ISO-C build problems
1908 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1909 non ISO-C code that stopped them being built using a more strict ISO-C
1910 compiler (e.g., IBM's C compiler).
1912 * Fixed build problem on IRIX 5
1914 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1915 wasn't able to compile compile on an IRIX 5 system.
1917 * Added execute permission to gdb/gdbserver/configure
1919 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1920 permission. This bug would cause configure to fail on a number of
1921 systems (Solaris, IRIX). Ref: server/519.
1923 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1925 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1926 has been updated to use constant array sizes.
1928 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1930 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1931 its generated DWARF Call Frame Info. This encoding was causing GDB to
1932 panic, that panic has been fixed. Ref: gdb/1628.
1934 * Fixed a problem when examining parameters in shared library code.
1936 When examining parameters in optimized shared library code generated
1937 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1938 not available''. GDB now correctly displays the variable's value.
1940 *** Changes in GDB 6.1:
1942 * Removed --with-mmalloc
1944 Support for the mmalloc memory manager has been removed, as it
1945 conflicted with the internal gdb byte cache.
1947 * Changes in AMD64 configurations
1949 The AMD64 target now includes the %cs and %ss registers. As a result
1950 the AMD64 remote protocol has changed; this affects the floating-point
1951 and SSE registers. If you rely on those registers for your debugging,
1952 you should upgrade gdbserver on the remote side.
1954 * Revised SPARC target
1956 The SPARC target has been completely revised, incorporating the
1957 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1958 support for LynxOS and SunOS 4 has been dropped. Calling functions
1959 from within GDB on operating systems with a non-executable stack
1960 (Solaris, OpenBSD) now works.
1964 GDB has a new C++ demangler which does a better job on the mangled
1965 names generated by current versions of g++. It also runs faster, so
1966 with this and other changes gdb should now start faster on large C++
1969 * DWARF 2 Location Expressions
1971 GDB support for location expressions has been extended to support function
1972 arguments and frame bases. Older versions of GDB could crash when they
1975 * C++ nested types and namespaces
1977 GDB's support for nested types and namespaces in C++ has been
1978 improved, especially if you use the DWARF 2 debugging format. (This
1979 is the default for recent versions of GCC on most platforms.)
1980 Specifically, if you have a class "Inner" defined within a class or
1981 namespace "Outer", then GDB realizes that the class's name is
1982 "Outer::Inner", not simply "Inner". This should greatly reduce the
1983 frequency of complaints about not finding RTTI symbols. In addition,
1984 if you are stopped at inside of a function defined within a namespace,
1985 GDB modifies its name lookup accordingly.
1987 * New native configurations
1989 NetBSD/amd64 x86_64-*-netbsd*
1990 OpenBSD/amd64 x86_64-*-openbsd*
1991 OpenBSD/alpha alpha*-*-openbsd*
1992 OpenBSD/sparc sparc-*-openbsd*
1993 OpenBSD/sparc64 sparc64-*-openbsd*
1995 * New debugging protocols
1997 M32R with SDI protocol m32r-*-elf*
1999 * "set prompt-escape-char" command deleted.
2001 The command "set prompt-escape-char" has been deleted. This command,
2002 and its very obscure effet on GDB's prompt, was never documented,
2003 tested, nor mentioned in the NEWS file.
2005 * OBSOLETE configurations and files
2007 Configurations that have been declared obsolete in this release have
2008 been commented out. Unless there is activity to revive these
2009 configurations, the next release of GDB will have their sources
2010 permanently REMOVED.
2012 Sun 3, running SunOS 3 m68*-*-sunos3*
2013 Sun 3, running SunOS 4 m68*-*-sunos4*
2014 Sun 2, running SunOS 3 m68000-*-sunos3*
2015 Sun 2, running SunOS 4 m68000-*-sunos4*
2016 Motorola 680x0 running LynxOS m68*-*-lynxos*
2017 AT&T 3b1/Unix pc m68*-att-*
2018 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2019 decstation mips-dec-* mips-little-*
2020 riscos mips-*-riscos* mips-*-sysv*
2021 sonymips mips-sony-*
2022 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2024 * REMOVED configurations and files
2026 SGI Irix-4.x mips-sgi-irix4 or iris4
2027 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2028 Z8000 simulator z8k-zilog-none or z8ksim
2029 Matsushita MN10200 w/simulator mn10200-*-*
2030 H8/500 simulator h8500-hitachi-hms or h8500hms
2031 HP/PA running BSD hppa*-*-bsd*
2032 HP/PA running OSF/1 hppa*-*-osf*
2033 HP/PA Pro target hppa*-*-pro*
2034 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2035 386BSD i[3456]86-*-bsd*
2036 Sequent family i[3456]86-sequent-sysv4*
2037 i[3456]86-sequent-sysv*
2038 i[3456]86-sequent-bsd*
2039 SPARC running LynxOS sparc-*-lynxos*
2040 SPARC running SunOS 4 sparc-*-sunos4*
2041 Tsqware Sparclet sparclet-*-*
2042 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2044 *** Changes in GDB 6.0:
2048 Support for debugging the Objective-C programming language has been
2049 integrated into GDB.
2051 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2053 DWARF 2's Call Frame Information makes available compiler generated
2054 information that more exactly describes the program's run-time stack.
2055 By using this information, GDB is able to provide more robust stack
2058 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2059 have been updated to use a new backtrace mechanism which includes
2060 DWARF 2 CFI support.
2064 GDB's remote protocol has been extended to include support for hosted
2065 file I/O (where the remote target uses GDB's file system). See GDB's
2066 remote protocol documentation for details.
2068 * All targets using the new architecture framework.
2070 All of GDB's targets have been updated to use the new internal
2071 architecture framework. The way is now open for future GDB releases
2072 to include cross-architecture native debugging support (i386 on amd64,
2075 * GNU/Linux's Thread Local Storage (TLS)
2077 GDB now includes support for for the GNU/Linux implementation of
2078 per-thread variables.
2080 * GNU/Linux's Native POSIX Thread Library (NPTL)
2082 GDB's thread code has been updated to work with either the new
2083 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2085 * Separate debug info.
2087 GDB, in conjunction with BINUTILS, now supports a mechanism for
2088 automatically loading debug information from a separate file. Instead
2089 of shipping full debug and non-debug versions of system libraries,
2090 system integrators can now instead ship just the stripped libraries
2091 and optional debug files.
2093 * DWARF 2 Location Expressions
2095 DWARF 2 Location Expressions allow the compiler to more completely
2096 describe the location of variables (even in optimized code) to the
2099 GDB now includes preliminary support for location expressions (support
2100 for DW_OP_piece is still missing).
2104 A number of long standing bugs that caused GDB to die while starting a
2105 Java application have been fixed. GDB's Java support is now
2106 considered "useable".
2108 * GNU/Linux support for fork, vfork, and exec.
2110 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2111 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2114 * GDB supports logging output to a file
2116 There are two new commands, "set logging" and "show logging", which can be
2117 used to capture GDB's output to a file.
2119 * The meaning of "detach" has changed for gdbserver
2121 The "detach" command will now resume the application, as documented. To
2122 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2125 * d10v, m68hc11 `regs' command deprecated
2127 The `info registers' command has been updated so that it displays the
2128 registers using a format identical to the old `regs' command.
2132 A new command, "maint set profile on/off", has been added. This command can
2133 be used to enable or disable profiling while running GDB, to profile a
2134 session or a set of commands. In addition there is a new configure switch,
2135 "--enable-profiling", which will cause GDB to be compiled with profiling
2136 data, for more informative profiling results.
2138 * Default MI syntax changed to "mi2".
2140 The default MI (machine interface) syntax, enabled by the command line
2141 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2142 "mi1", can be enabled by specifying the option "-i=mi1".
2144 Support for the original "mi0" syntax (included in GDB 5.0) has been
2147 Fix for gdb/192: removed extraneous space when displaying frame level.
2148 Fix for gdb/672: update changelist is now output in mi list format.
2149 Fix for gdb/702: a -var-assign that updates the value now shows up
2150 in a subsequent -var-update.
2152 * New native configurations.
2154 FreeBSD/amd64 x86_64-*-freebsd*
2156 * Multi-arched targets.
2158 HP/PA HPUX11 hppa*-*-hpux*
2159 Renesas M32R/D w/simulator m32r-*-elf*
2161 * OBSOLETE configurations and files
2163 Configurations that have been declared obsolete in this release have
2164 been commented out. Unless there is activity to revive these
2165 configurations, the next release of GDB will have their sources
2166 permanently REMOVED.
2168 Z8000 simulator z8k-zilog-none or z8ksim
2169 Matsushita MN10200 w/simulator mn10200-*-*
2170 H8/500 simulator h8500-hitachi-hms or h8500hms
2171 HP/PA running BSD hppa*-*-bsd*
2172 HP/PA running OSF/1 hppa*-*-osf*
2173 HP/PA Pro target hppa*-*-pro*
2174 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2175 Sequent family i[3456]86-sequent-sysv4*
2176 i[3456]86-sequent-sysv*
2177 i[3456]86-sequent-bsd*
2178 Tsqware Sparclet sparclet-*-*
2179 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2181 * REMOVED configurations and files
2184 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2185 IBM AIX PS/2 i[3456]86-*-aix
2186 i386 running Mach 3.0 i[3456]86-*-mach3*
2187 i386 running Mach i[3456]86-*-mach*
2188 i386 running OSF/1 i[3456]86-*osf1mk*
2189 HP/Apollo 68k Family m68*-apollo*-sysv*,
2191 m68*-hp-bsd*, m68*-hp-hpux*
2192 Argonaut Risc Chip (ARC) arc-*-*
2193 Mitsubishi D30V d30v-*-*
2194 Fujitsu FR30 fr30-*-elf*
2195 OS/9000 i[34]86-*-os9k
2196 I960 with MON960 i960-*-coff
2198 * MIPS $fp behavior changed
2200 The convenience variable $fp, for the MIPS, now consistently returns
2201 the address of the current frame's base. Previously, depending on the
2202 context, $fp could refer to either $sp or the current frame's base
2203 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2204 The GNU Source-Level Debugger''.
2206 *** Changes in GDB 5.3:
2208 * GNU/Linux shared library multi-threaded performance improved.
2210 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2211 `/proc', in preference to `ptrace' for memory reads. This may result
2212 in an improvement in the start-up time of multi-threaded, shared
2213 library applications when run under GDB. One GDB user writes: ``loads
2214 shared libs like mad''.
2216 * ``gdbserver'' now supports multi-threaded applications on some targets
2218 Support for debugging multi-threaded applications which use
2219 the GNU/Linux LinuxThreads package has been added for
2220 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2221 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2223 * GDB now supports C/C++ preprocessor macros.
2225 GDB now expands preprocessor macro invocations in C/C++ expressions,
2226 and provides various commands for showing macro definitions and how
2229 The new command `macro expand EXPRESSION' expands any macro
2230 invocations in expression, and shows the result.
2232 The new command `show macro MACRO-NAME' shows the definition of the
2233 macro named MACRO-NAME, and where it was defined.
2235 Most compilers don't include information about macros in the debugging
2236 information by default. In GCC 3.1, for example, you need to compile
2237 your program with the options `-gdwarf-2 -g3'. If the macro
2238 information is present in the executable, GDB will read it.
2240 * Multi-arched targets.
2242 DEC Alpha (partial) alpha*-*-*
2243 DEC VAX (partial) vax-*-*
2245 National Semiconductor NS32000 (partial) ns32k-*-*
2246 Motorola 68000 (partial) m68k-*-*
2247 Motorola MCORE mcore-*-*
2251 Fujitsu FRV architecture added by Red Hat frv*-*-*
2254 * New native configurations
2256 Alpha NetBSD alpha*-*-netbsd*
2257 SH NetBSD sh*-*-netbsdelf*
2258 MIPS NetBSD mips*-*-netbsd*
2259 UltraSPARC NetBSD sparc64-*-netbsd*
2261 * OBSOLETE configurations and files
2263 Configurations that have been declared obsolete in this release have
2264 been commented out. Unless there is activity to revive these
2265 configurations, the next release of GDB will have their sources
2266 permanently REMOVED.
2268 Mitsubishi D30V d30v-*-*
2269 OS/9000 i[34]86-*-os9k
2270 IBM AIX PS/2 i[3456]86-*-aix
2271 Fujitsu FR30 fr30-*-elf*
2272 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2273 Argonaut Risc Chip (ARC) arc-*-*
2274 i386 running Mach 3.0 i[3456]86-*-mach3*
2275 i386 running Mach i[3456]86-*-mach*
2276 i386 running OSF/1 i[3456]86-*osf1mk*
2277 HP/Apollo 68k Family m68*-apollo*-sysv*,
2279 m68*-hp-bsd*, m68*-hp-hpux*
2280 I960 with MON960 i960-*-coff
2282 * OBSOLETE languages
2284 CHILL, a Pascal like language used by telecommunications companies.
2286 * REMOVED configurations and files
2288 AMD 29k family via UDI a29k-amd-udi, udi29k
2289 A29K VxWorks a29k-*-vxworks
2290 AMD 29000 embedded, using EBMON a29k-none-none
2291 AMD 29000 embedded with COFF a29k-none-coff
2292 AMD 29000 embedded with a.out a29k-none-aout
2294 testsuite/gdb.hp/gdb.threads-hp/ directory
2296 * New command "set max-user-call-depth <nnn>"
2298 This command allows the user to limit the call depth of user-defined
2299 commands. The default is 1024.
2301 * Changes in FreeBSD/i386 native debugging.
2303 Support for the "generate-core-file" has been added.
2305 * New commands "dump", "append", and "restore".
2307 These commands allow data to be copied from target memory
2308 to a bfd-format or binary file (dump and append), and back
2309 from a file into memory (restore).
2311 * Improved "next/step" support on multi-processor Alpha Tru64.
2313 The previous single-step mechanism could cause unpredictable problems,
2314 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2315 of a software single-step mechanism prevents this.
2317 *** Changes in GDB 5.2.1:
2325 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2326 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2327 Fix, by Joel Brobecker imported from mainline.
2329 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2330 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2331 Fix, by Fred Fish, imported from mainline.
2333 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2334 Surprisingly enough, it works now.
2335 By Michal Ludvig, imported from mainline.
2337 i386 hardware watchpoint support:
2338 avoid misses on second run for some targets.
2339 By Pierre Muller, imported from mainline.
2341 *** Changes in GDB 5.2:
2343 * New command "set trust-readonly-sections on[off]".
2345 This command is a hint that tells gdb that read-only sections
2346 really are read-only (ie. that their contents will not change).
2347 In this mode, gdb will go to the object file rather than the
2348 target to read memory from read-only sections (such as ".text").
2349 This can be a significant performance improvement on some
2350 (notably embedded) targets.
2352 * New command "generate-core-file" (or "gcore").
2354 This new gdb command allows the user to drop a core file of the child
2355 process state at any time. So far it's been implemented only for
2356 GNU/Linux and Solaris, but should be relatively easily ported to other
2357 hosts. Argument is core file name (defaults to core.<pid>).
2359 * New command line option
2361 GDB now accepts --pid or -p followed by a process id.
2363 * Change in command line behavior -- corefiles vs. process ids.
2365 There is a subtle behavior in the way in which GDB handles
2366 command line arguments. The first non-flag argument is always
2367 a program to debug, but the second non-flag argument may either
2368 be a corefile or a process id. Previously, GDB would attempt to
2369 open the second argument as a corefile, and if that failed, would
2370 issue a superfluous error message and then attempt to attach it as
2371 a process. Now, if the second argument begins with a non-digit,
2372 it will be treated as a corefile. If it begins with a digit,
2373 GDB will attempt to attach it as a process, and if no such process
2374 is found, will then attempt to open it as a corefile.
2376 * Changes in ARM configurations.
2378 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2379 configuration is fully multi-arch.
2381 * New native configurations
2383 ARM NetBSD arm*-*-netbsd*
2384 x86 OpenBSD i[3456]86-*-openbsd*
2385 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2386 Sparc64 running FreeBSD sparc64-*-freebsd*
2390 Sanyo XStormy16 xstormy16-elf
2392 * OBSOLETE configurations and files
2394 Configurations that have been declared obsolete in this release have
2395 been commented out. Unless there is activity to revive these
2396 configurations, the next release of GDB will have their sources
2397 permanently REMOVED.
2399 AMD 29k family via UDI a29k-amd-udi, udi29k
2400 A29K VxWorks a29k-*-vxworks
2401 AMD 29000 embedded, using EBMON a29k-none-none
2402 AMD 29000 embedded with COFF a29k-none-coff
2403 AMD 29000 embedded with a.out a29k-none-aout
2405 testsuite/gdb.hp/gdb.threads-hp/ directory
2407 * REMOVED configurations and files
2409 TI TMS320C80 tic80-*-*
2411 PowerPC Solaris powerpcle-*-solaris*
2412 PowerPC Windows NT powerpcle-*-cygwin32
2413 PowerPC Netware powerpc-*-netware*
2414 Harris/CXUX m88k m88*-harris-cxux*
2415 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2416 ns32k-utek-sysv* ns32k-utek-*
2417 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2418 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2419 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2420 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2421 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2423 * Changes to command line processing
2425 The new `--args' feature can be used to specify command-line arguments
2426 for the inferior from gdb's command line.
2428 * Changes to key bindings
2430 There is a new `operate-and-get-next' function bound to `C-o'.
2432 *** Changes in GDB 5.1.1
2434 Fix compile problem on DJGPP.
2436 Fix a problem with floating-point registers on the i386 being
2439 Fix to stop GDB crashing on .debug_str debug info.
2441 Numerous documentation fixes.
2443 Numerous testsuite fixes.
2445 *** Changes in GDB 5.1:
2447 * New native configurations
2449 Alpha FreeBSD alpha*-*-freebsd*
2450 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2451 MIPS GNU/Linux mips*-*-linux*
2452 MIPS SGI Irix 6.x mips*-sgi-irix6*
2453 ia64 AIX ia64-*-aix*
2454 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2458 Motorola 68HC11 and 68HC12 m68hc11-elf
2460 UltraSparc running GNU/Linux sparc64-*-linux*
2462 * OBSOLETE configurations and files
2464 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2465 Harris/CXUX m88k m88*-harris-cxux*
2466 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2467 ns32k-utek-sysv* ns32k-utek-*
2468 TI TMS320C80 tic80-*-*
2470 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2471 PowerPC Solaris powerpcle-*-solaris*
2472 PowerPC Windows NT powerpcle-*-cygwin32
2473 PowerPC Netware powerpc-*-netware*
2474 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2475 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2476 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2477 Apple Macintosh (MPW) host N/A
2479 stuff.c (Program to stuff files into a specially prepared space in kdb)
2480 kdb-start.c (Main loop for the standalone kernel debugger)
2482 Configurations that have been declared obsolete in this release have
2483 been commented out. Unless there is activity to revive these
2484 configurations, the next release of GDB will have their sources
2485 permanently REMOVED.
2487 * REMOVED configurations and files
2489 Altos 3068 m68*-altos-*
2490 Convex c1-*-*, c2-*-*
2492 ARM RISCix arm-*-* (as host)
2496 * GDB has been converted to ISO C.
2498 GDB's source code has been converted to ISO C. In particular, the
2499 sources are fully protoized, and rely on standard headers being
2504 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2506 * The MI enabled by default.
2508 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2509 revised and enabled by default. Packages which use GDB as a debugging
2510 engine behind a UI or another front end are encouraged to switch to
2511 using the GDB/MI interface, instead of the old annotations interface
2512 which is now deprecated.
2514 * Support for debugging Pascal programs.
2516 GDB now includes support for debugging Pascal programs. The following
2517 main features are supported:
2519 - Pascal-specific data types such as sets;
2521 - automatic recognition of Pascal sources based on file-name
2524 - Pascal-style display of data types, variables, and functions;
2526 - a Pascal expression parser.
2528 However, some important features are not yet supported.
2530 - Pascal string operations are not supported at all;
2532 - there are some problems with boolean types;
2534 - Pascal type hexadecimal constants are not supported
2535 because they conflict with the internal variables format;
2537 - support for Pascal objects and classes is not full yet;
2539 - unlike Pascal, GDB is case-sensitive for symbol names.
2541 * Changes in completion.
2543 Commands such as `shell', `run' and `set args', which pass arguments
2544 to inferior programs, now complete on file names, similar to what
2545 users expect at the shell prompt.
2547 Commands which accept locations, such as `disassemble', `print',
2548 `breakpoint', `until', etc. now complete on filenames as well as
2549 program symbols. Thus, if you type "break foob TAB", and the source
2550 files linked into the programs include `foobar.c', that file name will
2551 be one of the candidates for completion. However, file names are not
2552 considered for completion after you typed a colon that delimits a file
2553 name from a name of a function in that file, as in "break foo.c:bar".
2555 `set demangle-style' completes on available demangling styles.
2557 * New platform-independent commands:
2559 It is now possible to define a post-hook for a command as well as a
2560 hook that runs before the command. For more details, see the
2561 documentation of `hookpost' in the GDB manual.
2563 * Changes in GNU/Linux native debugging.
2565 Support for debugging multi-threaded programs has been completely
2566 revised for all platforms except m68k and sparc. You can now debug as
2567 many threads as your system allows you to have.
2569 Attach/detach is supported for multi-threaded programs.
2571 Support for SSE registers was added for x86. This doesn't work for
2572 multi-threaded programs though.
2574 * Changes in MIPS configurations.
2576 Multi-arch support is enabled for all MIPS configurations.
2578 GDB can now be built as native debugger on SGI Irix 6.x systems for
2579 debugging n32 executables. (Debugging 64-bit executables is not yet
2582 * Unified support for hardware watchpoints in all x86 configurations.
2584 Most (if not all) native x86 configurations support hardware-assisted
2585 breakpoints and watchpoints in a unified manner. This support
2586 implements debug register sharing between watchpoints, which allows to
2587 put a virtually infinite number of watchpoints on the same address,
2588 and also supports watching regions up to 16 bytes with several debug
2591 The new maintenance command `maintenance show-debug-regs' toggles
2592 debugging print-outs in functions that insert, remove, and test
2593 watchpoints and hardware breakpoints.
2595 * Changes in the DJGPP native configuration.
2597 New command ``info dos sysinfo'' displays assorted information about
2598 the CPU, OS, memory, and DPMI server.
2600 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2601 display information about segment descriptors stored in GDT, LDT, and
2604 New commands ``info dos pde'' and ``info dos pte'' display entries
2605 from Page Directory and Page Tables (for now works with CWSDPMI only).
2606 New command ``info dos address-pte'' displays the Page Table entry for
2607 a given linear address.
2609 GDB can now pass command lines longer than 126 characters to the
2610 program being debugged (requires an update to the libdbg.a library
2611 which is part of the DJGPP development kit).
2613 DWARF2 debug info is now supported.
2615 It is now possible to `step' and `next' through calls to `longjmp'.
2617 * Changes in documentation.
2619 All GDB documentation was converted to GFDL, the GNU Free
2620 Documentation License.
2622 Tracepoints-related commands are now fully documented in the GDB
2625 TUI, the Text-mode User Interface, is now documented in the manual.
2627 Tracepoints-related commands are now fully documented in the GDB
2630 The "GDB Internals" manual now has an index. It also includes
2631 documentation of `ui_out' functions, GDB coding standards, x86
2632 hardware watchpoints, and memory region attributes.
2634 * GDB's version number moved to ``version.in''
2636 The Makefile variable VERSION has been replaced by the file
2637 ``version.in''. People creating GDB distributions should update the
2638 contents of this file.
2642 GUD support is now a standard part of the EMACS distribution.
2644 *** Changes in GDB 5.0:
2646 * Improved support for debugging FP programs on x86 targets
2648 Unified and much-improved support for debugging floating-point
2649 programs on all x86 targets. In particular, ``info float'' now
2650 displays the FP registers in the same format on all x86 targets, with
2651 greater level of detail.
2653 * Improvements and bugfixes in hardware-assisted watchpoints
2655 It is now possible to watch array elements, struct members, and
2656 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2657 on x86 targets no longer erroneously trigger when the address is
2660 * Improvements in the native DJGPP version of GDB
2662 The distribution now includes all the scripts and auxiliary files
2663 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2664 machines ``out of the box''.
2666 The DJGPP version can now debug programs that use signals. It is
2667 possible to catch signals that happened in the debuggee, deliver
2668 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2669 would kill the program being debugged.) Programs that hook hardware
2670 interrupts (keyboard, timer, etc.) can also be debugged.
2672 It is now possible to debug DJGPP programs that redirect their
2673 standard handles or switch them to raw (as opposed to cooked) mode, or
2674 even close them. The command ``run < foo > bar'' works as expected,
2675 and ``info terminal'' reports useful information about the debuggee's
2676 terminal, including raw/cooked mode, redirection, etc.
2678 The DJGPP version now uses termios functions for console I/O, which
2679 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2682 DOS-style file names with drive letters are now fully supported by
2685 It is now possible to debug DJGPP programs that switch their working
2686 directory. It is also possible to rerun the debuggee any number of
2687 times without restarting GDB; thus, you can use the same setup,
2688 breakpoints, etc. for many debugging sessions.
2690 * New native configurations
2692 ARM GNU/Linux arm*-*-linux*
2693 PowerPC GNU/Linux powerpc-*-linux*
2697 Motorola MCore mcore-*-*
2698 x86 VxWorks i[3456]86-*-vxworks*
2699 PowerPC VxWorks powerpc-*-vxworks*
2700 TI TMS320C80 tic80-*-*
2702 * OBSOLETE configurations
2704 Altos 3068 m68*-altos-*
2705 Convex c1-*-*, c2-*-*
2707 ARM RISCix arm-*-* (as host)
2710 Configurations that have been declared obsolete will be commented out,
2711 but the code will be left in place. If there is no activity to revive
2712 these configurations before the next release of GDB, the sources will
2713 be permanently REMOVED.
2715 * Gould support removed
2717 Support for the Gould PowerNode and NP1 has been removed.
2719 * New features for SVR4
2721 On SVR4 native platforms (such as Solaris), if you attach to a process
2722 without first loading a symbol file, GDB will now attempt to locate and
2723 load symbols from the running process's executable file.
2725 * Many C++ enhancements
2727 C++ support has been greatly improved. Overload resolution now works properly
2728 in almost all cases. RTTI support is on the way.
2730 * Remote targets can connect to a sub-program
2732 A popen(3) style serial-device has been added. This device starts a
2733 sub-process (such as a stand-alone simulator) and then communicates
2734 with that. The sub-program to run is specified using the syntax
2735 ``|<program> <args>'' vis:
2737 (gdb) set remotedebug 1
2738 (gdb) target extended-remote |mn10300-elf-sim program-args
2740 * MIPS 64 remote protocol
2742 A long standing bug in the mips64 remote protocol where by GDB
2743 expected certain 32 bit registers (ex SR) to be transfered as 32
2744 instead of 64 bits has been fixed.
2746 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2747 added to provide backward compatibility with older versions of GDB.
2749 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2751 The command ``set remotebinarydownload'' command has been replaced by
2752 ``set remote X-packet''. Other commands in ``set remote'' family
2753 include ``set remote P-packet''.
2755 * Breakpoint commands accept ranges.
2757 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2758 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2759 ``tracepoint passcount'' also accepts a range of tracepoints.
2761 * ``apropos'' command added.
2763 The ``apropos'' command searches through command names and
2764 documentation strings, printing out matches, making it much easier to
2765 try to find a command that does what you are looking for.
2769 A new machine oriented interface (MI) has been added to GDB. This
2770 interface is designed for debug environments running GDB as a separate
2771 process. This is part of the long term libGDB project. See the
2772 "GDB/MI" chapter of the GDB manual for further information. It can be
2773 enabled by configuring with:
2775 .../configure --enable-gdbmi
2777 *** Changes in GDB-4.18:
2779 * New native configurations
2781 HP-UX 10.20 hppa*-*-hpux10.20
2782 HP-UX 11.x hppa*-*-hpux11.0*
2783 M68K GNU/Linux m68*-*-linux*
2787 Fujitsu FR30 fr30-*-elf*
2788 Intel StrongARM strongarm-*-*
2789 Mitsubishi D30V d30v-*-*
2791 * OBSOLETE configurations
2793 Gould PowerNode, NP1 np1-*-*, pn-*-*
2795 Configurations that have been declared obsolete will be commented out,
2796 but the code will be left in place. If there is no activity to revive
2797 these configurations before the next release of GDB, the sources will
2798 be permanently REMOVED.
2802 As a compatibility experiment, GDB's source files buildsym.h and
2803 buildsym.c have been converted to pure standard C, no longer
2804 containing any K&R compatibility code. We believe that all systems in
2805 use today either come with a standard C compiler, or have a GCC port
2806 available. If this is not true, please report the affected
2807 configuration to bug-gdb@gnu.org immediately. See the README file for
2808 information about getting a standard C compiler if you don't have one
2813 GDB now uses readline 2.2.
2815 * set extension-language
2817 You can now control the mapping between filename extensions and source
2818 languages by using the `set extension-language' command. For instance,
2819 you can ask GDB to treat .c files as C++ by saying
2820 set extension-language .c c++
2821 The command `info extensions' lists all of the recognized extensions
2822 and their associated languages.
2824 * Setting processor type for PowerPC and RS/6000
2826 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2827 you can use the `set processor' command to specify what variant of the
2828 PowerPC family you are debugging. The command
2832 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2833 following PowerPC and RS6000 variants:
2835 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2836 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2838 403GC IBM PowerPC 403GC
2839 505 Motorola PowerPC 505
2840 860 Motorola PowerPC 860 or 850
2841 601 Motorola PowerPC 601
2842 602 Motorola PowerPC 602
2843 603 Motorola/IBM PowerPC 603 or 603e
2844 604 Motorola PowerPC 604 or 604e
2845 750 Motorola/IBM PowerPC 750 or 750
2847 At the moment, this command just tells GDB what to name the
2848 special-purpose processor registers. Since almost all the affected
2849 registers are inaccessible to user-level programs, this command is
2850 only useful for remote debugging in its present form.
2854 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2855 more extensive support for HP-UX. Added features include shared
2856 library support, kernel threads and hardware watchpoints for 11.00,
2857 support for HP's ANSI C and C++ compilers, and a compatibility mode
2858 for xdb and dbx commands.
2862 HP's donation includes the new concept of catchpoints, which is a
2863 generalization of the old catch command. On HP-UX, it is now possible
2864 to catch exec, fork, and vfork, as well as library loading.
2866 This means that the existing catch command has changed; its first
2867 argument now specifies the type of catch to be set up. See the
2868 output of "help catch" for a list of catchpoint types.
2870 * Debugging across forks
2872 On HP-UX, you can choose which process to debug when a fork() happens
2877 HP has donated a curses-based terminal user interface (TUI). To get
2878 it, build with --enable-tui. Although this can be enabled for any
2879 configuration, at present it only works for native HP debugging.
2881 * GDB remote protocol additions
2883 A new protocol packet 'X' that writes binary data is now available.
2884 Default behavior is to try 'X', then drop back to 'M' if the stub
2885 fails to respond. The settable variable `remotebinarydownload'
2886 allows explicit control over the use of 'X'.
2888 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2889 full 64-bit address. The command
2891 set remoteaddresssize 32
2893 can be used to revert to the old behaviour. For existing remote stubs
2894 the change should not be noticed, as the additional address information
2897 In order to assist in debugging stubs, you may use the maintenance
2898 command `packet' to send any text string to the stub. For instance,
2900 maint packet heythere
2902 sends the packet "$heythere#<checksum>". Note that it is very easy to
2903 disrupt a debugging session by sending the wrong packet at the wrong
2906 The compare-sections command allows you to compare section data on the
2907 target to what is in the executable file without uploading or
2908 downloading, by comparing CRC checksums.
2910 * Tracing can collect general expressions
2912 You may now collect general expressions at tracepoints. This requires
2913 further additions to the target-side stub; see tracepoint.c and
2914 doc/agentexpr.texi for further details.
2916 * mask-address variable for Mips
2918 For Mips targets, you may control the zeroing of the upper 32 bits of
2919 a 64-bit address by entering `set mask-address on'. This is mainly
2920 of interest to users of embedded R4xxx and R5xxx processors.
2922 * Higher serial baud rates
2924 GDB's serial code now allows you to specify baud rates 57600, 115200,
2925 230400, and 460800 baud. (Note that your host system may not be able
2926 to achieve all of these rates.)
2930 The i960 configuration now includes an initial implementation of a
2931 builtin simulator, contributed by Jim Wilson.
2934 *** Changes in GDB-4.17:
2936 * New native configurations
2938 Alpha GNU/Linux alpha*-*-linux*
2939 Unixware 2.x i[3456]86-unixware2*
2940 Irix 6.x mips*-sgi-irix6*
2941 PowerPC GNU/Linux powerpc-*-linux*
2942 PowerPC Solaris powerpcle-*-solaris*
2943 Sparc GNU/Linux sparc-*-linux*
2944 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2948 Argonaut Risc Chip (ARC) arc-*-*
2949 Hitachi H8/300S h8300*-*-*
2950 Matsushita MN10200 w/simulator mn10200-*-*
2951 Matsushita MN10300 w/simulator mn10300-*-*
2952 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2953 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2954 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2955 Mitsubishi D10V w/simulator d10v-*-*
2956 Mitsubishi M32R/D w/simulator m32r-*-elf*
2957 Tsqware Sparclet sparclet-*-*
2958 NEC V850 w/simulator v850-*-*
2960 * New debugging protocols
2962 ARM with RDI protocol arm*-*-*
2963 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2964 DDB and LSI variants of PMON protocol mips*-*-*
2965 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2966 PowerPC with SDS protocol powerpc{,le}-*-eabi
2967 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2971 All configurations can now understand and use the DWARF 2 debugging
2972 format. The choice is automatic, if the symbol file contains DWARF 2
2977 GDB now includes basic Java language support. This support is
2978 only useful with Java compilers that produce native machine code.
2980 * solib-absolute-prefix and solib-search-path
2982 For SunOS and SVR4 shared libraries, you may now set the prefix for
2983 loading absolute shared library symbol files, and the search path for
2984 locating non-absolute shared library symbol files.
2986 * Live range splitting
2988 GDB can now effectively debug code for which GCC has performed live
2989 range splitting as part of its optimization. See gdb/doc/LRS for
2990 more details on the expected format of the stabs information.
2994 GDB's support for the GNU Hurd, including thread debugging, has been
2995 updated to work with current versions of the Hurd.
2999 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3000 instruction set. ARM GDB automatically detects when Thumb
3001 instructions are in use, and adjusts disassembly and backtracing
3006 GDB's MIPS target configurations now handle the MIP16 16-bit
3011 GDB now includes support for overlays; if an executable has been
3012 linked such that multiple sections are based at the same address, GDB
3013 will decide which section to use for symbolic info. You can choose to
3014 control the decision manually, using overlay commands, or implement
3015 additional target-side support and use "overlay load-target" to bring
3016 in the overlay mapping. Do "help overlay" for more detail.
3020 The command "info symbol <address>" displays information about
3021 the symbol at the specified address.
3025 The standard remote protocol now includes an extension that allows
3026 asynchronous collection and display of trace data. This requires
3027 extensive support in the target-side debugging stub. Tracing mode
3028 includes a new interaction mode in GDB and new commands: see the
3029 file tracepoint.c for more details.
3033 Configurations for embedded MIPS now include a simulator contributed
3034 by Cygnus Solutions. The simulator supports the instruction sets
3035 of most MIPS variants.
3039 Sparc configurations may now include the ERC32 simulator contributed
3040 by the European Space Agency. The simulator is not built into
3041 Sparc targets by default; configure with --enable-sim to include it.
3045 For target configurations that may include multiple variants of a
3046 basic architecture (such as MIPS and SH), you may now set the
3047 architecture explicitly. "set arch" sets, "info arch" lists
3048 the possible architectures.
3050 *** Changes in GDB-4.16:
3052 * New native configurations
3054 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3055 M68K NetBSD m68k-*-netbsd*
3056 PowerPC AIX 4.x powerpc-*-aix*
3057 PowerPC MacOS powerpc-*-macos*
3058 PowerPC Windows NT powerpcle-*-cygwin32
3059 RS/6000 AIX 4.x rs6000-*-aix4*
3063 ARM with RDP protocol arm-*-*
3064 I960 with MON960 i960-*-coff
3065 MIPS VxWorks mips*-*-vxworks*
3066 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3067 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3069 Matra Sparclet sparclet-*-*
3073 The powerpc-eabi configuration now includes the PSIM simulator,
3074 contributed by Andrew Cagney, with assistance from Mike Meissner.
3075 PSIM is a very elaborate model of the PowerPC, including not only
3076 basic instruction set execution, but also details of execution unit
3077 performance and I/O hardware. See sim/ppc/README for more details.
3081 GDB now works with Solaris 2.5.
3083 * Windows 95/NT native
3085 GDB will now work as a native debugger on Windows 95 and Windows NT.
3086 To build it from source, you must use the "gnu-win32" environment,
3087 which uses a DLL to emulate enough of Unix to run the GNU tools.
3088 Further information, binaries, and sources are available at
3089 ftp.cygnus.com, under pub/gnu-win32.
3091 * dont-repeat command
3093 If a user-defined command includes the command `dont-repeat', then the
3094 command will not be repeated if the user just types return. This is
3095 useful if the command is time-consuming to run, so that accidental
3096 extra keystrokes don't run the same command many times.
3098 * Send break instead of ^C
3100 The standard remote protocol now includes an option to send a break
3101 rather than a ^C to the target in order to interrupt it. By default,
3102 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3104 * Remote protocol timeout
3106 The standard remote protocol includes a new variable `remotetimeout'
3107 that allows you to set the number of seconds before GDB gives up trying
3108 to read from the target. The default value is 2.
3110 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3112 By default GDB will automatically keep track of objects as they are
3113 loaded and unloaded by the dynamic linker. By using the command `set
3114 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3115 when shared library events occur, thus allowing you to set breakpoints
3116 in shared libraries which are explicitly loaded by the inferior.
3118 Note this feature does not work on hpux8. On hpux9 you must link
3119 /usr/lib/end.o into your program. This feature should work
3120 automatically on hpux10.
3122 * Irix 5.x hardware watchpoint support
3124 Irix 5 configurations now support the use of hardware watchpoints.
3126 * Mips protocol "SYN garbage limit"
3128 When debugging a Mips target using the `target mips' protocol, you
3129 may set the number of characters that GDB will ignore by setting
3130 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3131 every character. The default value is 1050.
3133 * Recording and replaying remote debug sessions
3135 If you set `remotelogfile' to the name of a file, gdb will write to it
3136 a recording of a remote debug session. This recording may then be
3137 replayed back to gdb using "gdbreplay". See gdbserver/README for
3138 details. This is useful when you have a problem with GDB while doing
3139 remote debugging; you can make a recording of the session and send it
3140 to someone else, who can then recreate the problem.
3142 * Speedups for remote debugging
3144 GDB includes speedups for downloading and stepping MIPS systems using
3145 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3146 and more efficient S-record downloading.
3148 * Memory use reductions and statistics collection
3150 GDB now uses less memory and reports statistics about memory usage.
3151 Try the `maint print statistics' command, for example.
3153 *** Changes in GDB-4.15:
3155 * Psymtabs for XCOFF
3157 The symbol reader for AIX GDB now uses partial symbol tables. This
3158 can greatly improve startup time, especially for large executables.
3160 * Remote targets use caching
3162 Remote targets now use a data cache to speed up communication with the
3163 remote side. The data cache could lead to incorrect results because
3164 it doesn't know about volatile variables, thus making it impossible to
3165 debug targets which use memory mapped I/O devices. `set remotecache
3166 off' turns the the data cache off.
3168 * Remote targets may have threads
3170 The standard remote protocol now includes support for multiple threads
3171 in the target system, using new protocol commands 'H' and 'T'. See
3172 gdb/remote.c for details.
3176 If GDB is configured with `--enable-netrom', then it will include
3177 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3178 acts as though it is a bank of ROM on the target board, but you can
3179 write into it over the network. GDB's support consists only of
3180 support for fast loading into the emulated ROM; to debug, you must use
3181 another protocol, such as standard remote protocol. The usual
3182 sequence is something like
3184 target nrom <netrom-hostname>
3186 target remote <netrom-hostname>:1235
3190 GDB now includes support for the Apple Macintosh, as a host only. It
3191 may be run as either an MPW tool or as a standalone application, and
3192 it can debug through the serial port. All the usual GDB commands are
3193 available, but to the target command, you must supply "serial" as the
3194 device type instead of "/dev/ttyXX". See mpw-README in the main
3195 directory for more information on how to build. The MPW configuration
3196 scripts */mpw-config.in support only a few targets, and only the
3197 mips-idt-ecoff target has been tested.
3201 GDB configuration now uses autoconf. This is not user-visible,
3202 but does simplify configuration and building.
3206 GDB now supports hpux10.
3208 *** Changes in GDB-4.14:
3210 * New native configurations
3212 x86 FreeBSD i[345]86-*-freebsd
3213 x86 NetBSD i[345]86-*-netbsd
3214 NS32k NetBSD ns32k-*-netbsd
3215 Sparc NetBSD sparc-*-netbsd
3219 A29K VxWorks a29k-*-vxworks
3220 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3221 CPU32 EST-300 emulator m68*-*-est*
3222 PowerPC ELF powerpc-*-elf
3225 * Alpha OSF/1 support for procfs
3227 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3228 possible to attach to running processes. As the mounting of the /proc
3229 filesystem is optional on the Alpha, GDB automatically determines
3230 the availability of /proc during startup. This can lead to problems
3231 if /proc is unmounted after GDB has been started.
3233 * Arguments to user-defined commands
3235 User commands may accept up to 10 arguments separated by whitespace.
3236 Arguments are accessed within the user command via $arg0..$arg9. A
3239 print $arg0 + $arg1 + $arg2
3241 To execute the command use:
3244 Defines the command "adder" which prints the sum of its three arguments.
3245 Note the arguments are text substitutions, so they may reference variables,
3246 use complex expressions, or even perform inferior function calls.
3248 * New `if' and `while' commands
3250 This makes it possible to write more sophisticated user-defined
3251 commands. Both commands take a single argument, which is the
3252 expression to evaluate, and must be followed by the commands to
3253 execute, one per line, if the expression is nonzero, the list being
3254 terminated by the word `end'. The `if' command list may include an
3255 `else' word, which causes the following commands to be executed only
3256 if the expression is zero.
3258 * Fortran source language mode
3260 GDB now includes partial support for Fortran 77. It will recognize
3261 Fortran programs and can evaluate a subset of Fortran expressions, but
3262 variables and functions may not be handled correctly. GDB will work
3263 with G77, but does not yet know much about symbols emitted by other
3266 * Better HPUX support
3268 Most debugging facilities now work on dynamic executables for HPPAs
3269 running hpux9 or later. You can attach to running dynamically linked
3270 processes, but by default the dynamic libraries will be read-only, so
3271 for instance you won't be able to put breakpoints in them. To change
3272 that behavior do the following before running the program:
3278 This will cause the libraries to be mapped private and read-write.
3279 To revert to the normal behavior, do this:
3285 You cannot set breakpoints or examine data in the library until after
3286 the library is loaded if the function/data symbols do not have
3289 GDB can now also read debug symbols produced by the HP C compiler on
3290 HPPAs (sorry, no C++, Fortran or 68k support).
3292 * Target byte order now dynamically selectable
3294 You can choose which byte order to use with a target system, via the
3295 commands "set endian big" and "set endian little", and you can see the
3296 current setting by using "show endian". You can also give the command
3297 "set endian auto", in which case GDB will use the byte order
3298 associated with the executable. Currently, only embedded MIPS
3299 configurations support dynamic selection of target byte order.
3301 * New DOS host serial code
3303 This version uses DPMI interrupts to handle buffered I/O, so you
3304 no longer need to run asynctsr when debugging boards connected to
3307 *** Changes in GDB-4.13:
3309 * New "complete" command
3311 This lists all the possible completions for the rest of the line, if it
3312 were to be given as a command itself. This is intended for use by emacs.
3314 * Trailing space optional in prompt
3316 "set prompt" no longer adds a space for you after the prompt you set. This
3317 allows you to set a prompt which ends in a space or one that does not.
3319 * Breakpoint hit counts
3321 "info break" now displays a count of the number of times the breakpoint
3322 has been hit. This is especially useful in conjunction with "ignore"; you
3323 can ignore a large number of breakpoint hits, look at the breakpoint info
3324 to see how many times the breakpoint was hit, then run again, ignoring one
3325 less than that number, and this will get you quickly to the last hit of
3328 * Ability to stop printing at NULL character
3330 "set print null-stop" will cause GDB to stop printing the characters of
3331 an array when the first NULL is encountered. This is useful when large
3332 arrays actually contain only short strings.
3334 * Shared library breakpoints
3336 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3337 breakpoints in shared libraries before the executable is run.
3339 * Hardware watchpoints
3341 There is a new hardware breakpoint for the watch command for sparclite
3342 targets. See gdb/sparclite/hw_breakpoint.note.
3344 Hardware watchpoints are also now supported under GNU/Linux.
3348 Annotations have been added. These are for use with graphical interfaces,
3349 and are still experimental. Currently only gdba.el uses these.
3351 * Improved Irix 5 support
3353 GDB now works properly with Irix 5.2.
3355 * Improved HPPA support
3357 GDB now works properly with the latest GCC and GAS.
3359 * New native configurations
3361 Sequent PTX4 i[34]86-sequent-ptx4
3362 HPPA running OSF/1 hppa*-*-osf*
3363 Atari TT running SVR4 m68*-*-sysv4*
3364 RS/6000 LynxOS rs6000-*-lynxos*
3368 OS/9000 i[34]86-*-os9k
3369 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3372 * Hitachi SH7000 and E7000-PC ICE support
3374 There is now support for communicating with the Hitachi E7000-PC ICE.
3375 This is available automatically when GDB is configured for the SH.
3379 As usual, a variety of small fixes and improvements, both generic
3380 and configuration-specific. See the ChangeLog for more detail.
3382 *** Changes in GDB-4.12:
3384 * Irix 5 is now supported
3388 GDB-4.12 on the HPPA has a number of changes which make it unable
3389 to debug the output from the currently released versions of GCC and
3390 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3391 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3392 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3395 *** Changes in GDB-4.11:
3397 * User visible changes:
3401 The "set remotedebug" option is now consistent between the mips remote
3402 target, remote targets using the gdb-specific protocol, UDI (AMD's
3403 debug protocol for the 29k) and the 88k bug monitor. It is now an
3404 integer specifying a debug level (normally 0 or 1, but 2 means more
3405 debugging info for the mips target).
3407 * DEC Alpha native support
3409 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3410 debug info, but GDB works fairly well with the DEC compiler and should
3411 work with a future GCC release. See the README file for a few
3412 Alpha-specific notes.
3414 * Preliminary thread implementation
3416 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3418 * LynxOS native and target support for 386
3420 This release has been hosted on LynxOS 2.2, and also can be configured
3421 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3424 * Improvements in C++ mangling/demangling.
3426 This release has much better g++ debugging, specifically in name
3427 mangling/demangling, virtual function calls, print virtual table,
3428 call methods, ...etc.
3430 *** Changes in GDB-4.10:
3432 * User visible changes:
3434 Remote debugging using the GDB-specific (`target remote') protocol now
3435 supports the `load' command. This is only useful if you have some
3436 other way of getting the stub to the target system, and you can put it
3437 somewhere in memory where it won't get clobbered by the download.
3439 Filename completion now works.
3441 When run under emacs mode, the "info line" command now causes the
3442 arrow to point to the line specified. Also, "info line" prints
3443 addresses in symbolic form (as well as hex).
3445 All vxworks based targets now support a user settable option, called
3446 vxworks-timeout. This option represents the number of seconds gdb
3447 should wait for responses to rpc's. You might want to use this if
3448 your vxworks target is, perhaps, a slow software simulator or happens
3449 to be on the far side of a thin network line.
3453 This release contains support for using a DEC alpha as a GDB host for
3454 cross debugging. Native alpha debugging is not supported yet.
3457 *** Changes in GDB-4.9:
3461 This is the first GDB release which is accompanied by a matching testsuite.
3462 The testsuite requires installation of dejagnu, which should be available
3463 via ftp from most sites that carry GNU software.
3467 'Cfront' style demangling has had its name changed to 'ARM' style, to
3468 emphasize that it was written from the specifications in the C++ Annotated
3469 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3470 disclaimers, it still generated too much confusion with users attempting to
3471 use gdb with AT&T cfront.
3475 GDB now uses a standard remote interface to a simulator library.
3476 So far, the library contains simulators for the Zilog Z8001/2, the
3477 Hitachi H8/300, H8/500 and Super-H.
3479 * New targets supported
3481 H8/300 simulator h8300-hitachi-hms or h8300hms
3482 H8/500 simulator h8500-hitachi-hms or h8500hms
3483 SH simulator sh-hitachi-hms or sh
3484 Z8000 simulator z8k-zilog-none or z8ksim
3485 IDT MIPS board over serial line mips-idt-ecoff
3487 Cross-debugging to GO32 targets is supported. It requires a custom
3488 version of the i386-stub.c module which is integrated with the
3489 GO32 memory extender.
3491 * New remote protocols
3493 MIPS remote debugging protocol.
3495 * New source languages supported
3497 This version includes preliminary support for Chill, a Pascal like language
3498 used by telecommunications companies. Chill support is also being integrated
3499 into the GNU compiler, but we don't know when it will be publically available.
3502 *** Changes in GDB-4.8:
3504 * HP Precision Architecture supported
3506 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3507 version of this support was available as a set of patches from the
3508 University of Utah. GDB does not support debugging of programs
3509 compiled with the HP compiler, because HP will not document their file
3510 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3511 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3513 Many problems in the preliminary version have been fixed.
3515 * Faster and better demangling
3517 We have improved template demangling and fixed numerous bugs in the GNU style
3518 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3519 character types (wchar_t) are now supported. Demangling of each symbol is now
3520 only done once, and is cached when the symbol table for a file is read in.
3521 This results in a small increase in memory usage for C programs, a moderate
3522 increase in memory usage for C++ programs, and a fantastic speedup in
3525 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3526 from the specifications in the Annotated Reference Manual, which AT&T's
3527 compiler does not actually implement.
3529 * G++ multiple inheritance compiler problem
3531 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3532 inheritance lattices was reworked to properly discover ambiguities. We
3533 recently found an example which causes this new algorithm to fail in a
3534 very subtle way, producing bad debug information for those classes.
3535 The file 'gcc.patch' (in this directory) can be applied to gcc to
3536 circumvent the problem. A future GCC release will contain a complete
3539 The previous G++ debug info problem (mentioned below for the gdb-4.7
3540 release) is fixed in gcc version 2.3.2.
3542 * Improved configure script
3544 The `configure' script will now attempt to guess your system type if
3545 you don't supply a host system type. The old scheme of supplying a
3546 host system triplet is preferable over using this. All the magic is
3547 done in the new `config.guess' script. Examine it for details.
3549 We have also brought our configure script much more in line with the FSF's
3550 version. It now supports the --with-xxx options. In particular,
3551 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3552 The resulting GDB will not be able to read arbitrary object file formats --
3553 only the format ``expected'' to be used on the configured target system.
3554 We hope to make this the default in a future release.
3556 * Documentation improvements
3558 There's new internal documentation on how to modify GDB, and how to
3559 produce clean changes to the code. We implore people to read it
3560 before submitting changes.
3562 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3563 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3564 `info' files are also provided. To build `info' files from scratch,
3565 you will need the latest `makeinfo' release, which will be available in
3566 a future texinfo-X.Y release.
3568 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3569 We're not sure exactly which versions have this problem, but it has
3570 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3571 or better. If that isn't possible, there is a patch in
3572 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3573 around this problem.
3577 GDB now supports array constants that can be used in expressions typed in by
3578 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3579 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3582 The new directory `gdb/sparclite' contains a program that demonstrates
3583 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3585 * New native hosts supported
3587 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3588 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3590 * New targets supported
3592 AMD 29k family via UDI a29k-amd-udi or udi29k
3594 * New file formats supported
3596 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3597 HPUX core files, and SCO 3.2v2 core files.
3601 Attaching to processes now works again; thanks for the many bug reports.
3603 We have also stomped on a bunch of core dumps caused by
3604 printf_filtered("%s") problems.
3606 We eliminated a copyright problem on the rpc and ptrace header files
3607 for VxWorks, which was discovered at the last minute during the 4.7
3608 release. You should now be able to build a VxWorks GDB.
3610 You can now interrupt gdb while an attached process is running. This
3611 will cause the attached process to stop, and give control back to GDB.
3613 We fixed problems caused by using too many file descriptors
3614 for reading symbols from object files and libraries. This was
3615 especially a problem for programs that used many (~100) shared
3618 The `step' command now only enters a subroutine if there is line number
3619 information for the subroutine. Otherwise it acts like the `next'
3620 command. Previously, `step' would enter subroutines if there was
3621 any debugging information about the routine. This avoids problems
3622 when using `cc -g1' on MIPS machines.
3624 * Internal improvements
3626 GDB's internal interfaces have been improved to make it easier to support
3627 debugging of multiple languages in the future.
3629 GDB now uses a common structure for symbol information internally.
3630 Minimal symbols (derived from linkage symbols in object files), partial
3631 symbols (from a quick scan of debug information), and full symbols
3632 contain a common subset of information, making it easier to write
3633 shared code that handles any of them.
3635 * New command line options
3637 We now accept --silent as an alias for --quiet.
3641 The memory-mapped-malloc library is now licensed under the GNU Library
3642 General Public License.
3644 *** Changes in GDB-4.7:
3646 * Host/native/target split
3648 GDB has had some major internal surgery to untangle the support for
3649 hosts and remote targets. Now, when you configure GDB for a remote
3650 target, it will no longer load in all of the support for debugging
3651 local programs on the host. When fully completed and tested, this will
3652 ensure that arbitrary host/target combinations are possible.
3654 The primary conceptual shift is to separate the non-portable code in
3655 GDB into three categories. Host specific code is required any time GDB
3656 is compiled on that host, regardless of the target. Target specific
3657 code relates to the peculiarities of the target, but can be compiled on
3658 any host. Native specific code is everything else: it can only be
3659 built when the host and target are the same system. Child process
3660 handling and core file support are two common `native' examples.
3662 GDB's use of /proc for controlling Unix child processes is now cleaner.
3663 It has been split out into a single module under the `target_ops' vector,
3664 plus two native-dependent functions for each system that uses /proc.
3666 * New hosts supported
3668 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3669 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3670 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3672 * New targets supported
3674 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3675 68030 and CPU32 m68030-*-*, m68332-*-*
3677 * New native hosts supported
3679 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3680 (386bsd is not well tested yet)
3681 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3683 * New file formats supported
3685 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3686 supports reading of `a.out.adobe' object files, which are an a.out
3687 format extended with minimal information about multiple sections.
3691 `show copying' is the same as the old `info copying'.
3692 `show warranty' is the same as `info warrantee'.
3693 These were renamed for consistency. The old commands continue to work.
3695 `info handle' is a new alias for `info signals'.
3697 You can now define pre-command hooks, which attach arbitrary command
3698 scripts to any command. The commands in the hook will be executed
3699 prior to the user's command. You can also create a hook which will be
3700 executed whenever the program stops. See gdb.texinfo.
3704 We now deal with Cfront style name mangling, and can even extract type
3705 info from mangled symbols. GDB can automatically figure out which
3706 symbol mangling style your C++ compiler uses.
3708 Calling of methods and virtual functions has been improved as well.
3712 The crash that occured when debugging Sun Ansi-C compiled binaries is
3713 fixed. This was due to mishandling of the extra N_SO stabs output
3716 We also finally got Ultrix 4.2 running in house, and fixed core file
3717 support, with help from a dozen people on the net.
3719 John M. Farrell discovered that the reason that single-stepping was so
3720 slow on all of the Mips based platforms (primarily SGI and DEC) was
3721 that we were trying to demangle and lookup a symbol used for internal
3722 purposes on every instruction that was being stepped through. Changing
3723 the name of that symbol so that it couldn't be mistaken for a C++
3724 mangled symbol sped things up a great deal.
3726 Rich Pixley sped up symbol lookups in general by getting much smarter
3727 about when C++ symbol mangling is necessary. This should make symbol
3728 completion (TAB on the command line) much faster. It's not as fast as
3729 we'd like, but it's significantly faster than gdb-4.6.
3733 A new user controllable variable 'call_scratch_address' can
3734 specify the location of a scratch area to be used when GDB
3735 calls a function in the target. This is necessary because the
3736 usual method of putting the scratch area on the stack does not work
3737 in systems that have separate instruction and data spaces.
3739 We integrated changes to support the 29k UDI (Universal Debugger
3740 Interface), but discovered at the last minute that we didn't have all
3741 of the appropriate copyright paperwork. We are working with AMD to
3742 resolve this, and hope to have it available soon.
3746 We have sped up the remote serial line protocol, especially for targets
3747 with lots of registers. It now supports a new `expedited status' ('T')
3748 message which can be used in place of the existing 'S' status message.
3749 This allows the remote stub to send only the registers that GDB
3750 needs to make a quick decision about single-stepping or conditional
3751 breakpoints, eliminating the need to fetch the entire register set for
3752 each instruction being stepped through.
3754 The GDB remote serial protocol now implements a write-through cache for
3755 registers, only re-reading the registers if the target has run.
3757 There is also a new remote serial stub for SPARC processors. You can
3758 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3759 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3760 processor with a serial port.
3764 Configure.in files have become much easier to read and modify. A new
3765 `table driven' format makes it more obvious what configurations are
3766 supported, and what files each one uses.
3770 There is a new opcodes library which will eventually contain all of the
3771 disassembly routines and opcode tables. At present, it only contains
3772 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3773 disassembler (binutils/objdump) to share these routines.
3775 The libiberty library is now copylefted under the GNU Library General
3776 Public License. This allows more liberal use, and was done so libg++
3777 can use it. This makes no difference to GDB, since the Library License
3778 grants all the rights from the General Public License.
3782 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3783 reference to the stabs symbol info used by the debugger. It is (as far
3784 as we know) the only published document on this fascinating topic. We
3785 encourage you to read it, compare it to the stabs information on your
3786 system, and send improvements on the document in general (to
3787 bug-gdb@prep.ai.mit.edu).
3789 And, of course, many bugs have been fixed.
3792 *** Changes in GDB-4.6:
3794 * Better support for C++ function names
3796 GDB now accepts as input the "demangled form" of C++ overloaded function
3797 names and member function names, and can do command completion on such names
3798 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3799 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3800 Make use of command completion, it is your friend.
3802 GDB also now accepts a variety of C++ mangled symbol formats. They are
3803 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3804 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3805 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3806 for the list of formats.
3808 * G++ symbol mangling problem
3810 Recent versions of gcc have a bug in how they emit debugging information for
3811 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3812 directory) can be applied to gcc to fix the problem. Alternatively, if you
3813 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3814 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3815 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3818 * New 'maintenance' command
3820 All of the commands related to hacking GDB internals have been moved out of
3821 the main command set, and now live behind the 'maintenance' command. This
3822 can also be abbreviated as 'mt'. The following changes were made:
3824 dump-me -> maintenance dump-me
3825 info all-breakpoints -> maintenance info breakpoints
3826 printmsyms -> maintenance print msyms
3827 printobjfiles -> maintenance print objfiles
3828 printpsyms -> maintenance print psymbols
3829 printsyms -> maintenance print symbols
3831 The following commands are new:
3833 maintenance demangle Call internal GDB demangler routine to
3834 demangle a C++ link name and prints the result.
3835 maintenance print type Print a type chain for a given symbol
3837 * Change to .gdbinit file processing
3839 We now read the $HOME/.gdbinit file before processing the argv arguments
3840 (e.g. reading symbol files or core files). This allows global parameters to
3841 be set, which will apply during the symbol reading. The ./.gdbinit is still
3842 read after argv processing.
3844 * New hosts supported
3846 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3848 GNU/Linux support i386-unknown-linux or linux
3850 We are also including code to support the HP/PA running BSD and HPUX. This
3851 is almost guaranteed not to work, as we didn't have time to test or build it
3852 for this release. We are including it so that the more adventurous (or
3853 masochistic) of you can play with it. We also had major problems with the
3854 fact that the compiler that we got from HP doesn't support the -g option.
3857 * New targets supported
3859 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3861 * More smarts about finding #include files
3863 GDB now remembers the compilation directory for all include files, and for
3864 all files from which C is generated (like yacc and lex sources). This
3865 greatly improves GDB's ability to find yacc/lex sources, and include files,
3866 especially if you are debugging your program from a directory different from
3867 the one that contains your sources.
3869 We also fixed a bug which caused difficulty with listing and setting
3870 breakpoints in include files which contain C code. (In the past, you had to
3871 try twice in order to list an include file that you hadn't looked at before.)
3873 * Interesting infernals change
3875 GDB now deals with arbitrary numbers of sections, where the symbols for each
3876 section must be relocated relative to that section's landing place in the
3877 target's address space. This work was needed to support ELF with embedded
3878 stabs used by Solaris-2.0.
3880 * Bug fixes (of course!)
3882 There have been loads of fixes for the following things:
3883 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3884 i960, stabs, DOS(GO32), procfs, etc...
3886 See the ChangeLog for details.
3888 *** Changes in GDB-4.5:
3890 * New machines supported (host and target)
3892 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3894 SGI Irix-4.x mips-sgi-irix4 or iris4
3896 * New malloc package
3898 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3899 Mmalloc is capable of handling mutiple heaps of memory. It is also
3900 capable of saving a heap to a file, and then mapping it back in later.
3901 This can be used to greatly speedup the startup of GDB by using a
3902 pre-parsed symbol table which lives in a mmalloc managed heap. For
3903 more details, please read mmalloc/mmalloc.texi.
3907 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3908 'help info proc' for details.
3910 * MIPS ecoff symbol table format
3912 The code that reads MIPS symbol table format is now supported on all hosts.
3913 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3916 * File name changes for MS-DOS
3918 Many files in the config directories have been renamed to make it easier to
3919 support GDB on MS-DOSe systems (which have very restrictive file name
3920 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3921 environment) is close to working but has some remaining problems. Note
3922 that debugging of DOS programs is not supported, due to limitations
3923 in the ``operating system'', but it can be used to host cross-debugging.
3925 * Cross byte order fixes
3927 Many fixes have been made to support cross debugging of Sparc and MIPS
3928 targets from hosts whose byte order differs.
3930 * New -mapped and -readnow options
3932 If memory-mapped files are available on your system through the 'mmap'
3933 system call, you can use the -mapped option on the `file' or
3934 `symbol-file' commands to cause GDB to write the symbols from your
3935 program into a reusable file. If the program you are debugging is
3936 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3937 Future GDB debugging sessions will notice the presence of this file,
3938 and will quickly map in symbol information from it, rather than reading
3939 the symbol table from the executable program. Using the '-mapped'
3940 option in a GDB `file' or `symbol-file' command has the same effect as
3941 starting GDB with the '-mapped' command-line option.
3943 You can cause GDB to read the entire symbol table immediately by using
3944 the '-readnow' option with any of the commands that load symbol table
3945 information (or on the GDB command line). This makes the command
3946 slower, but makes future operations faster.
3948 The -mapped and -readnow options are typically combined in order to
3949 build a `fred.syms' file that contains complete symbol information.
3950 A simple GDB invocation to do nothing but build a `.syms' file for future
3953 gdb -batch -nx -mapped -readnow programname
3955 The `.syms' file is specific to the host machine on which GDB is run.
3956 It holds an exact image of GDB's internal symbol table. It cannot be
3957 shared across multiple host platforms.
3959 * longjmp() handling
3961 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3962 siglongjmp() without losing control. This feature has not yet been ported to
3963 all systems. It currently works on many 386 platforms, all MIPS-based
3964 platforms (SGI, DECstation, etc), and Sun3/4.
3968 Preliminary work has been put in to support the new Solaris OS from Sun. At
3969 this time, it can control and debug processes, but it is not capable of
3974 As always, many many bug fixes. The major areas were with g++, and mipsread.
3975 People using the MIPS-based platforms should experience fewer mysterious
3976 crashes and trashed symbol tables.
3978 *** Changes in GDB-4.4:
3980 * New machines supported (host and target)
3982 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3984 BSD Reno on Vax vax-dec-bsd
3985 Ultrix on Vax vax-dec-ultrix
3987 * New machines supported (target)
3989 AMD 29000 embedded, using EBMON a29k-none-none
3993 GDB continues to improve its handling of C++. `References' work better.
3994 The demangler has also been improved, and now deals with symbols mangled as
3995 per the Annotated C++ Reference Guide.
3997 GDB also now handles `stabs' symbol information embedded in MIPS
3998 `ecoff' symbol tables. Since the ecoff format was not easily
3999 extensible to handle new languages such as C++, this appeared to be a
4000 good way to put C++ debugging info into MIPS binaries. This option
4001 will be supported in the GNU C compiler, version 2, when it is
4004 * New features for SVR4
4006 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4007 shared libraries. Debugging dynamically linked programs should present
4008 only minor differences from debugging statically linked programs.
4010 The `info proc' command will print out information about any process
4011 on an SVR4 system (including the one you are debugging). At the moment,
4012 it prints the address mappings of the process.
4014 If you bring up GDB on another SVR4 system, please send mail to
4015 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4017 * Better dynamic linking support in SunOS
4019 Reading symbols from shared libraries which contain debugging symbols
4020 now works properly. However, there remain issues such as automatic
4021 skipping of `transfer vector' code during function calls, which
4022 make it harder to debug code in a shared library, than to debug the
4023 same code linked statically.
4027 GDB is now using the latest `getopt' routines from the FSF. This
4028 version accepts the -- prefix for options with long names. GDB will
4029 continue to accept the old forms (-option and +option) as well.
4030 Various single letter abbreviations for options have been explicity
4031 added to the option table so that they won't get overshadowed in the
4032 future by other options that begin with the same letter.
4036 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4037 Many assorted bugs have been handled. Many more remain to be handled.
4038 See the various ChangeLog files (primarily in gdb and bfd) for details.
4041 *** Changes in GDB-4.3:
4043 * New machines supported (host and target)
4045 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4046 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4047 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4049 * Almost SCO Unix support
4051 We had hoped to support:
4052 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4053 (except for core file support), but we discovered very late in the release
4054 that it has problems with process groups that render gdb unusable. Sorry
4055 about that. I encourage people to fix it and post the fixes.
4057 * Preliminary ELF and DWARF support
4059 GDB can read ELF object files on System V Release 4, and can handle
4060 debugging records for C, in DWARF format, in ELF files. This support
4061 is preliminary. If you bring up GDB on another SVR4 system, please
4062 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4067 GDB now uses the latest `readline' library. One user-visible change
4068 is that two tabs will list possible command completions, which previously
4069 required typing M-? (meta-question mark, or ESC ?).
4073 The `stepi' bug that many of you noticed has been squashed.
4074 Many bugs in C++ have been handled. Many more remain to be handled.
4075 See the various ChangeLog files (primarily in gdb and bfd) for details.
4077 * State of the MIPS world (in case you wondered):
4079 GDB can understand the symbol tables emitted by the compilers
4080 supplied by most vendors of MIPS-based machines, including DEC. These
4081 symbol tables are in a format that essentially nobody else uses.
4083 Some versions of gcc come with an assembler post-processor called
4084 mips-tfile. This program is required if you want to do source-level
4085 debugging of gcc-compiled programs. I believe FSF does not ship
4086 mips-tfile with gcc version 1, but it will eventually come with gcc
4089 Debugging of g++ output remains a problem. g++ version 1.xx does not
4090 really support it at all. (If you're lucky, you should be able to get
4091 line numbers and stack traces to work, but no parameters or local
4092 variables.) With some work it should be possible to improve the
4095 When gcc version 2 is released, you will have somewhat better luck.
4096 However, even then you will get confusing results for inheritance and
4099 We will eventually provide full debugging of g++ output on
4100 DECstations. This will probably involve some kind of stabs-in-ecoff
4101 encapulation, but the details have not been worked out yet.
4104 *** Changes in GDB-4.2:
4106 * Improved configuration
4108 Only one copy of `configure' exists now, and it is not self-modifying.
4109 Porting BFD is simpler.
4113 The `step' and `next' commands now only stop at the first instruction
4114 of a source line. This prevents the multiple stops that used to occur
4115 in switch statements, for-loops, etc. `Step' continues to stop if a
4116 function that has debugging information is called within the line.
4120 Lots of small bugs fixed. More remain.
4122 * New host supported (not target)
4124 Intel 386 PC clone running Mach i386-none-mach
4127 *** Changes in GDB-4.1:
4129 * Multiple source language support
4131 GDB now has internal scaffolding to handle several source languages.
4132 It determines the type of each source file from its filename extension,
4133 and will switch expression parsing and number formatting to match the
4134 language of the function in the currently selected stack frame.
4135 You can also specifically set the language to be used, with
4136 `set language c' or `set language modula-2'.
4140 GDB now has preliminary support for the GNU Modula-2 compiler,
4141 currently under development at the State University of New York at
4142 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4143 continue through the fall of 1991 and into 1992.
4145 Other Modula-2 compilers are currently not supported, and attempting to
4146 debug programs compiled with them will likely result in an error as the
4147 symbol table is read. Feel free to work on it, though!
4149 There are hooks in GDB for strict type checking and range checking,
4150 in the `Modula-2 philosophy', but they do not currently work.
4154 GDB can now write to executable and core files (e.g. patch
4155 a variable's value). You must turn this switch on, specify
4156 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4157 by assigning a new value to a variable. Modifications take
4160 * Automatic SunOS shared library reading
4162 When you run your program, GDB automatically determines where its
4163 shared libraries (if any) have been loaded, and reads their symbols.
4164 The `share' command is no longer needed. This also works when
4165 examining core files.
4169 You can specify the number of lines that the `list' command shows.
4172 * New machines supported (host and target)
4174 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4175 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4176 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4178 * New hosts supported (not targets)
4180 IBM RT/PC: romp-ibm-aix or rtpc
4182 * New targets supported (not hosts)
4184 AMD 29000 embedded with COFF a29k-none-coff
4185 AMD 29000 embedded with a.out a29k-none-aout
4186 Ultracomputer remote kernel debug a29k-nyu-kern
4188 * New remote interfaces
4194 *** Changes in GDB-4.0:
4198 Wide output is wrapped at good places to make the output more readable.
4200 Gdb now supports cross-debugging from a host machine of one type to a
4201 target machine of another type. Communication with the target system
4202 is over serial lines. The ``target'' command handles connecting to the
4203 remote system; the ``load'' command will download a program into the
4204 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4205 also supports debugging of realtime processes running under VxWorks,
4206 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4207 stub on the target system.
4209 New CPUs supported include the AMD 29000 and Intel 960.
4211 GDB now reads object files and symbol tables via a ``binary file''
4212 library, which allows a single copy of GDB to debug programs of multiple
4213 object file types such as a.out and coff.
4215 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4216 refcard.dvi and refcard.ps are available to format it).
4219 * Control-Variable user interface simplified
4221 All variables that control the operation of the debugger can be set
4222 by the ``set'' command, and displayed by the ``show'' command.
4224 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4225 ``Show prompt'' produces the response:
4226 Gdb's prompt is new-gdb=>.
4228 What follows are the NEW set commands. The command ``help set'' will
4229 print a complete list of old and new set commands. ``help set FOO''
4230 will give a longer description of the variable FOO. ``show'' will show
4231 all of the variable descriptions and their current settings.
4233 confirm on/off: Enables warning questions for operations that are
4234 hard to recover from, e.g. rerunning the program while
4235 it is already running. Default is ON.
4237 editing on/off: Enables EMACS style command line editing
4238 of input. Previous lines can be recalled with
4239 control-P, the current line can be edited with control-B,
4240 you can search for commands with control-R, etc.
4243 history filename NAME: NAME is where the gdb command history
4244 will be stored. The default is .gdb_history,
4245 or the value of the environment variable
4248 history size N: The size, in commands, of the command history. The
4249 default is 256, or the value of the environment variable
4252 history save on/off: If this value is set to ON, the history file will
4253 be saved after exiting gdb. If set to OFF, the
4254 file will not be saved. The default is OFF.
4256 history expansion on/off: If this value is set to ON, then csh-like
4257 history expansion will be performed on
4258 command line input. The default is OFF.
4260 radix N: Sets the default radix for input and output. It can be set
4261 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4262 in the current radix, so "set radix 10" is always a no-op.
4264 height N: This integer value is the number of lines on a page. Default
4265 is 24, the current `stty rows'' setting, or the ``li#''
4266 setting from the termcap entry matching the environment
4269 width N: This integer value is the number of characters on a line.
4270 Default is 80, the current `stty cols'' setting, or the ``co#''
4271 setting from the termcap entry matching the environment
4274 Note: ``set screensize'' is obsolete. Use ``set height'' and
4275 ``set width'' instead.
4277 print address on/off: Print memory addresses in various command displays,
4278 such as stack traces and structure values. Gdb looks
4279 more ``symbolic'' if you turn this off; it looks more
4280 ``machine level'' with it on. Default is ON.
4282 print array on/off: Prettyprint arrays. New convenient format! Default
4285 print demangle on/off: Print C++ symbols in "source" form if on,
4288 print asm-demangle on/off: Same, for assembler level printouts
4291 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4294 * Support for Epoch Environment.
4296 The epoch environment is a version of Emacs v18 with windowing. One
4297 new command, ``inspect'', is identical to ``print'', except that if you
4298 are running in the epoch environment, the value is printed in its own
4302 * Support for Shared Libraries
4304 GDB can now debug programs and core files that use SunOS shared libraries.
4305 Symbols from a shared library cannot be referenced
4306 before the shared library has been linked with the program (this
4307 happens after you type ``run'' and before the function main() is entered).
4308 At any time after this linking (including when examining core files
4309 from dynamically linked programs), gdb reads the symbols from each
4310 shared library when you type the ``sharedlibrary'' command.
4311 It can be abbreviated ``share''.
4313 sharedlibrary REGEXP: Load shared object library symbols for files
4314 matching a unix regular expression. No argument
4315 indicates to load symbols for all shared libraries.
4317 info sharedlibrary: Status of loaded shared libraries.
4322 A watchpoint stops execution of a program whenever the value of an
4323 expression changes. Checking for this slows down execution
4324 tremendously whenever you are in the scope of the expression, but is
4325 quite useful for catching tough ``bit-spreader'' or pointer misuse
4326 problems. Some machines such as the 386 have hardware for doing this
4327 more quickly, and future versions of gdb will use this hardware.
4329 watch EXP: Set a watchpoint (breakpoint) for an expression.
4331 info watchpoints: Information about your watchpoints.
4333 delete N: Deletes watchpoint number N (same as breakpoints).
4334 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4335 enable N: Re-enables watchpoint number N (same as breakpoints).
4338 * C++ multiple inheritance
4340 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4343 * C++ exception handling
4345 Gdb now supports limited C++ exception handling. Besides the existing
4346 ability to breakpoint on an exception handler, gdb can breakpoint on
4347 the raising of an exception (before the stack is peeled back to the
4350 catch FOO: If there is a FOO exception handler in the dynamic scope,
4351 set a breakpoint to catch exceptions which may be raised there.
4352 Multiple exceptions (``catch foo bar baz'') may be caught.
4354 info catch: Lists all exceptions which may be caught in the
4355 current stack frame.
4358 * Minor command changes
4360 The command ``call func (arg, arg, ...)'' now acts like the print
4361 command, except it does not print or save a value if the function's result
4362 is void. This is similar to dbx usage.
4364 The ``up'' and ``down'' commands now always print the frame they end up
4365 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4366 frames without printing.
4368 * New directory command
4370 'dir' now adds directories to the FRONT of the source search path.
4371 The path starts off empty. Source files that contain debug information
4372 about the directory in which they were compiled can be found even
4373 with an empty path; Sun CC and GCC include this information. If GDB can't
4374 find your source file in the current directory, type "dir .".
4376 * Configuring GDB for compilation
4378 For normal use, type ``./configure host''. See README or gdb.texinfo
4381 GDB now handles cross debugging. If you are remotely debugging between
4382 two different machines, type ``./configure host -target=targ''.
4383 Host is the machine where GDB will run; targ is the machine
4384 where the program that you are debugging will run.