1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.2
6 * New command line options
8 -data-directory DIR Specify DIR as the "data-directory".
9 This is mostly for testing purposes.
11 * The "maint set python auto-load on|off" command has been renamed to
12 "set auto-load-scripts on|off".
14 * GDB has a new command: "set directories".
15 It is like the "dir" command except that it replaces the
16 source path list instead of augmenting it.
19 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
20 has been integrated into GDB.
24 ** GDB values in Python are now callable if the value represents a
25 function. For example, if 'some_value' represents a function that
26 takes two integer parameters and returns a value, you can call
27 that function like so:
29 result = some_value (10,20)
31 ** Module gdb.types has been added.
32 It contains a collection of utilities for working with gdb.Types objects:
33 get_basic_type, has_field, make_enum_dict.
35 ** Module gdb.printing has been added.
36 It contains utilities for writing and registering pretty-printers.
37 New classes: PrettyPrinter, SubPrettyPrinter,
38 RegexpCollectionPrettyPrinter.
39 New function: register_pretty_printer.
41 ** New commands "info pretty-printers", "enable pretty-printer" and
42 "disable pretty-printer" have been added.
44 ** gdb.parameter("directories") is now available.
48 ** GDB now puts template parameters in scope when debugging in an
49 instantiation. For example, if you have:
51 template<int X> int func (void) { return X; }
53 then if you step into func<5>, "print X" will show "5". This
54 feature requires proper debuginfo support from the compiler; it
57 ** The motion commands "next", "finish", "until", and "advance" now
58 work better when exceptions are thrown. In particular, GDB will
59 no longer lose control of the inferior; instead, the GDB will
60 stop the inferior at the point at which the exception is caught.
61 This functionality requires a change in the exception handling
62 code that was introduced in GCC 4.5.
64 * GDB now follows GCC's rules on accessing volatile objects when
65 reading or writing target state during expression evaluation.
66 One notable difference to prior behavior is that "print x = 0"
67 no longer generates a read of x; the value of the assignment is
68 now always taken directly from the value being assigned.
70 * GDB now has some support for using labels in the program's source in
71 linespecs. For instance, you can use "advance label" to continue
74 * GDB now has support for reading and writing a new .gdb_index
75 section. This section holds a fast index of DWARF debugging
76 information and can be used to greatly speed up GDB startup and
77 operation. See the documentation for `save gdb-index' for details.
79 * The "watch" command now accepts an optional "-location" argument.
80 When used, this causes GDB to watch the memory referred to by the
81 expression. Such a watchpoint is never deleted due to it going out
84 * GDB now supports thread debugging of core dumps on GNU/Linux.
86 GDB now activates thread debugging using the libthread_db library
87 when debugging GNU/Linux core dumps, similarly to when debugging
88 live processes. As a result, when debugging a core dump file, GDB
89 is now able to display pthread_t ids of threads. For example, "info
90 threads" shows the same output as when debugging the process when it
91 was live. In earlier releases, you'd see something like this:
94 * 1 LWP 6780 main () at main.c:10
96 While now you see this:
99 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
101 It is also now possible to inspect TLS variables when debugging core
104 When debugging a core dump generated on a machine other than the one
105 used to run GDB, you may need to point GDB at the correct
106 libthread_db library with the "set libthread-db-search-path"
107 command. See the user manual for more details on this command.
109 * New features in the GDB remote stub, GDBserver
111 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
112 and i686 LynxOS (version 5.x).
114 * Ada task switching is now supported on sparc-elf targets when
115 debugging a program using the Ravenscar Profile. For more information,
116 see the "Tasking Support when using the Ravenscar Profile" section
117 in the GDB user manual.
119 * Guile support was removed.
121 *** Changes in GDB 7.2
123 * Shared library support for remote targets by default
125 When GDB is configured for a generic, non-OS specific target, like
126 for example, --target=arm-eabi or one of the many *-*-elf targets,
127 GDB now queries remote stubs for loaded shared libraries using the
128 `qXfer:libraries:read' packet. Previously, shared library support
129 was always disabled for such configurations.
133 ** Argument Dependent Lookup (ADL)
135 In C++ ADL lookup directs function search to the namespaces of its
136 arguments even if the namespace has not been imported.
146 Here the compiler will search for `foo' in the namespace of 'b'
147 and find A::foo. GDB now supports this. This construct is commonly
148 used in the Standard Template Library for operators.
150 ** Improved User Defined Operator Support
152 In addition to member operators, GDB now supports lookup of operators
153 defined in a namespace and imported with a `using' directive, operators
154 defined in the global scope, operators imported implicitly from an
155 anonymous namespace, and the ADL operators mentioned in the previous
157 GDB now also supports proper overload resolution for all the previously
158 mentioned flavors of operators.
160 ** static const class members
162 Printing of static const class members that are initialized in the
163 class definition has been fixed.
165 * Windows Thread Information Block access.
167 On Windows targets, GDB now supports displaying the Windows Thread
168 Information Block (TIB) structure. This structure is visible either
169 by using the new command `info w32 thread-information-block' or, by
170 dereferencing the new convenience variable named `$_tlb', a
171 thread-specific pointer to the TIB. This feature is also supported
172 when remote debugging using GDBserver.
176 Static tracepoints are calls in the user program into a tracing
177 library. One such library is a port of the LTTng kernel tracer to
178 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
179 When debugging with GDBserver, GDB now supports combining the GDB
180 tracepoint machinery with such libraries. For example: the user can
181 use GDB to probe a static tracepoint marker (a call from the user
182 program into the tracing library) with the new "strace" command (see
183 "New commands" below). This creates a "static tracepoint" in the
184 breakpoint list, that can be manipulated with the same feature set
185 as fast and regular tracepoints. E.g., collect registers, local and
186 global variables, collect trace state variables, and define
187 tracepoint conditions. In addition, the user can collect extra
188 static tracepoint marker specific data, by collecting the new
189 $_sdata internal variable. When analyzing the trace buffer, you can
190 inspect $_sdata like any other variable available to GDB. For more
191 information, see the "Tracepoints" chapter in GDB user manual. New
192 remote packets have been defined to support static tracepoints, see
193 the "New remote packets" section below.
195 * Better reconstruction of tracepoints after disconnected tracing
197 GDB will attempt to download the original source form of tracepoint
198 definitions when starting a trace run, and then will upload these
199 upon reconnection to the target, resulting in a more accurate
200 reconstruction of the tracepoints that are in use on the target.
204 You can now exercise direct control over the ways that GDB can
205 affect your program. For instance, you can disallow the setting of
206 breakpoints, so that the program can run continuously (assuming
207 non-stop mode). In addition, the "observer" variable is available
208 to switch all of the different controls; in observer mode, GDB
209 cannot affect the target's behavior at all, which is useful for
210 tasks like diagnosing live systems in the field.
212 * The new convenience variable $_thread holds the number of the
219 Return the address of the Windows Thread Information Block of a given thread.
223 In response to several of the tracepoint packets, the target may now
224 also respond with a number of intermediate `qRelocInsn' request
225 packets before the final result packet, to have GDB handle
226 relocating an instruction to execute at a different address. This
227 is particularly useful for stubs that support fast tracepoints. GDB
228 reports support for this feature in the qSupported packet.
232 List static tracepoint markers in the target program.
236 List static tracepoint markers at a given address in the target
239 qXfer:statictrace:read
241 Read the static trace data collected (by a `collect $_sdata'
242 tracepoint action). The remote stub reports support for this packet
243 to gdb's qSupported query.
247 Send the current settings of GDB's permission flags.
251 Send part of the source (textual) form of a tracepoint definition,
252 which includes location, conditional, and action list.
254 * The source command now accepts a -s option to force searching for the
255 script in the source search path even if the script name specifies
258 * New features in the GDB remote stub, GDBserver
260 - GDBserver now support tracepoints (including fast tracepoints, and
261 static tracepoints). The feature is currently supported by the
262 i386-linux and amd64-linux builds. See the "Tracepoints support
263 in gdbserver" section in the manual for more information.
265 GDBserver JIT compiles the tracepoint's conditional agent
266 expression bytecode into native code whenever possible for low
267 overhead dynamic tracepoints conditionals. For such tracepoints,
268 an expression that examines program state is evaluated when the
269 tracepoint is reached, in order to determine whether to capture
270 trace data. If the condition is simple and false, processing the
271 tracepoint finishes very quickly and no data is gathered.
273 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
274 for static tracepoints support.
276 - GDBserver now supports x86_64 Windows 64-bit debugging.
278 * GDB now sends xmlRegisters= in qSupported packet to indicate that
279 it understands register description.
281 * The --batch flag now disables pagination and queries.
283 * X86 general purpose registers
285 GDB now supports reading/writing byte, word and double-word x86
286 general purpose registers directly. This means you can use, say,
287 $ah or $ax to refer, respectively, to the byte register AH and
288 16-bit word register AX that are actually portions of the 32-bit
289 register EAX or 64-bit register RAX.
291 * The `commands' command now accepts a range of breakpoints to modify.
292 A plain `commands' following a command that creates multiple
293 breakpoints affects all the breakpoints set by that command. This
294 applies to breakpoints set by `rbreak', and also applies when a
295 single `break' command creates multiple breakpoints (e.g.,
296 breakpoints on overloaded c++ functions).
298 * The `rbreak' command now accepts a filename specification as part of
299 its argument, limiting the functions selected by the regex to those
300 in the specified file.
302 * Support for remote debugging Windows and SymbianOS shared libraries
303 from Unix hosts has been improved. Non Windows GDB builds now can
304 understand target reported file names that follow MS-DOS based file
305 system semantics, such as file names that include drive letters and
306 use the backslash character as directory separator. This makes it
307 possible to transparently use the "set sysroot" and "set
308 solib-search-path" on Unix hosts to point as host copies of the
309 target's shared libraries. See the new command "set
310 target-file-system-kind" described below, and the "Commands to
311 specify files" section in the user manual for more information.
315 eval template, expressions...
316 Convert the values of one or more expressions under the control
317 of the string template to a command line, and call it.
319 set target-file-system-kind unix|dos-based|auto
320 show target-file-system-kind
321 Set or show the assumed file system kind for target reported file
324 save breakpoints <filename>
325 Save all current breakpoint definitions to a file suitable for use
326 in a later debugging session. To read the saved breakpoint
327 definitions, use the `source' command.
329 `save tracepoints' is a new alias for `save-tracepoints'. The latter
332 info static-tracepoint-markers
333 Display information about static tracepoint markers in the target.
335 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
336 Define a static tracepoint by probing a marker at the given
337 function, line, address, or marker ID.
341 Enable and disable observer mode.
343 set may-write-registers on|off
344 set may-write-memory on|off
345 set may-insert-breakpoints on|off
346 set may-insert-tracepoints on|off
347 set may-insert-fast-tracepoints on|off
348 set may-interrupt on|off
349 Set individual permissions for GDB effects on the target. Note that
350 some of these settings can have undesirable or surprising
351 consequences, particularly when changed in the middle of a session.
352 For instance, disabling the writing of memory can prevent
353 breakpoints from being inserted, cause single-stepping to fail, or
354 even crash your program, if you disable after breakpoints have been
355 inserted. However, GDB should not crash.
357 set record memory-query on|off
358 show record memory-query
359 Control whether to stop the inferior if memory changes caused
360 by an instruction cannot be recorded.
365 The disassemble command now supports "start,+length" form of two arguments.
369 ** GDB now provides a new directory location, called the python directory,
370 where Python scripts written for GDB can be installed. The location
371 of that directory is <data-directory>/python, where <data-directory>
372 is the GDB data directory. For more details, see section `Scripting
373 GDB using Python' in the manual.
375 ** The GDB Python API now has access to breakpoints, symbols, symbol
376 tables, program spaces, inferiors, threads and frame's code blocks.
377 Additionally, GDB Parameters can now be created from the API, and
378 manipulated via set/show in the CLI.
380 ** New functions gdb.target_charset, gdb.target_wide_charset,
381 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
383 ** New exception gdb.GdbError.
385 ** Pretty-printers are now also looked up in the current program space.
387 ** Pretty-printers can now be individually enabled and disabled.
389 ** GDB now looks for names of Python scripts to auto-load in a
390 special section named `.debug_gdb_scripts', in addition to looking
391 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
393 * Tracepoint actions were unified with breakpoint commands. In particular,
394 there are no longer differences in "info break" output for breakpoints and
395 tracepoints and the "commands" command can be used for both tracepoints and
400 ARM Symbian arm*-*-symbianelf*
402 * D language support.
403 GDB now supports debugging programs written in the D programming
406 * GDB now supports the extended ptrace interface for PowerPC which is
407 available since Linux kernel version 2.6.34. This automatically enables
408 any hardware breakpoints and additional hardware watchpoints available in
409 the processor. The old ptrace interface exposes just one hardware
410 watchpoint and no hardware breakpoints.
412 * GDB is now able to use the Data Value Compare (DVC) register available on
413 embedded PowerPC processors to implement in hardware simple watchpoint
414 conditions of the form:
416 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
418 This works in native GDB running on Linux kernels with the extended ptrace
419 interface mentioned above.
421 *** Changes in GDB 7.1
427 GDB now supports importing of namespaces in C++. This enables the
428 user to inspect variables from imported namespaces. Support for
429 namepace aliasing has also been added. So, if a namespace is
430 aliased in the current scope (e.g. namepace C=A; ) the user can
431 print variables using the alias (e.g. (gdb) print C::x).
435 All known bugs relating to the printing of virtual base class were
436 fixed. It is now possible to call overloaded static methods using a
441 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
442 and reinterpret_cast<> are now handled by the C++ expression parser.
446 Xilinx MicroBlaze microblaze-*-*
451 Xilinx MicroBlaze microblaze
454 * Multi-program debugging.
456 GDB now has support for multi-program (a.k.a. multi-executable or
457 multi-exec) debugging. This allows for debugging multiple inferiors
458 simultaneously each running a different program under the same GDB
459 session. See "Debugging Multiple Inferiors and Programs" in the
460 manual for more information. This implied some user visible changes
461 in the multi-inferior support. For example, "info inferiors" now
462 lists inferiors that are not running yet or that have exited
463 already. See also "New commands" and "New options" below.
465 * New tracing features
467 GDB's tracepoint facility now includes several new features:
469 ** Trace state variables
471 GDB tracepoints now include support for trace state variables, which
472 are variables managed by the target agent during a tracing
473 experiment. They are useful for tracepoints that trigger each
474 other, so for instance one tracepoint can count hits in a variable,
475 and then a second tracepoint has a condition that is true when the
476 count reaches a particular value. Trace state variables share the
477 $-syntax of GDB convenience variables, and can appear in both
478 tracepoint actions and condition expressions. Use the "tvariable"
479 command to create, and "info tvariables" to view; see "Trace State
480 Variables" in the manual for more detail.
484 GDB now includes an option for defining fast tracepoints, which
485 targets may implement more efficiently, such as by installing a jump
486 into the target agent rather than a trap instruction. The resulting
487 speedup can be by two orders of magnitude or more, although the
488 tradeoff is that some program locations on some target architectures
489 might not allow fast tracepoint installation, for instance if the
490 instruction to be replaced is shorter than the jump. To request a
491 fast tracepoint, use the "ftrace" command, with syntax identical to
492 the regular trace command.
494 ** Disconnected tracing
496 It is now possible to detach GDB from the target while it is running
497 a trace experiment, then reconnect later to see how the experiment
498 is going. In addition, a new variable disconnected-tracing lets you
499 tell the target agent whether to continue running a trace if the
500 connection is lost unexpectedly.
504 GDB now has the ability to save the trace buffer into a file, and
505 then use that file as a target, similarly to you can do with
506 corefiles. You can select trace frames, print data that was
507 collected in them, and use tstatus to display the state of the
508 tracing run at the moment that it was saved. To create a trace
509 file, use "tsave <filename>", and to use it, do "target tfile
512 ** Circular trace buffer
514 You can ask the target agent to handle the trace buffer as a
515 circular buffer, discarding the oldest trace frames to make room for
516 newer ones, by setting circular-trace-buffer to on. This feature may
517 not be available for all target agents.
522 The disassemble command, when invoked with two arguments, now requires
523 the arguments to be comma-separated.
526 The info variables command now displays variable definitions. Files
527 which only declare a variable are not shown.
530 The source command is now capable of sourcing Python scripts.
531 This feature is dependent on the debugger being build with Python
534 Related to this enhancement is also the introduction of a new command
535 "set script-extension" (see below).
537 * New commands (for set/show, see "New options" below)
539 record save [<FILENAME>]
540 Save a file (in core file format) containing the process record
541 execution log for replay debugging at a later time.
543 record restore <FILENAME>
544 Restore the process record execution log that was saved at an
545 earlier time, for replay debugging.
547 add-inferior [-copies <N>] [-exec <FILENAME>]
550 clone-inferior [-copies <N>] [ID]
551 Make a new inferior ready to execute the same program another
557 maint info program-spaces
558 List the program spaces loaded into GDB.
560 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
561 show remote interrupt-sequence
562 Allow the user to select one of ^C, a BREAK signal or BREAK-g
563 as the sequence to the remote target in order to interrupt the execution.
564 Ctrl-C is a default. Some system prefers BREAK which is high level of
565 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
566 Magic SysRq g. It is BREAK signal and character 'g'.
568 set remote interrupt-on-connect [on | off]
569 show remote interrupt-on-connect
570 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
571 remote target when gdb connects to it. This is needed when you debug
574 set remotebreak [on | off]
576 Deprecated. Use "set/show remote interrupt-sequence" instead.
578 tvariable $NAME [ = EXP ]
579 Create or modify a trace state variable.
582 List trace state variables and their values.
584 delete tvariable $NAME ...
585 Delete one or more trace state variables.
588 Evaluate the given expressions without collecting anything into the
589 trace buffer. (Valid in tracepoint actions only.)
591 ftrace FN / FILE:LINE / *ADDR
592 Define a fast tracepoint at the given function, line, or address.
594 * New expression syntax
596 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
597 GDB now parses 0b101010 identically with 42.
601 set follow-exec-mode new|same
602 show follow-exec-mode
603 Control whether GDB reuses the same inferior across an exec call or
604 creates a new one. This is useful to be able to restart the old
605 executable after the inferior having done an exec call.
607 set default-collect EXPR, ...
609 Define a list of expressions to be collected at each tracepoint.
610 This is a useful way to ensure essential items are not overlooked,
611 such as registers or a critical global variable.
613 set disconnected-tracing
614 show disconnected-tracing
615 If set to 1, the target is instructed to continue tracing if it
616 loses its connection to GDB. If 0, the target is to stop tracing
619 set circular-trace-buffer
620 show circular-trace-buffer
621 If set to on, the target is instructed to use a circular trace buffer
622 and discard the oldest trace frames instead of stopping the trace due
623 to a full trace buffer. If set to off, the trace stops when the buffer
624 fills up. Some targets may not support this.
626 set script-extension off|soft|strict
627 show script-extension
628 If set to "off", the debugger does not perform any script language
629 recognition, and all sourced files are assumed to be GDB scripts.
630 If set to "soft" (the default), files are sourced according to
631 filename extension, falling back to GDB scripts if the first
633 If set to "strict", files are sourced according to filename extension.
635 set ada trust-PAD-over-XVS on|off
636 show ada trust-PAD-over-XVS
637 If off, activate a workaround against a bug in the debugging information
638 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
639 the GCC sources for more information about the GNAT encoding and
640 PAD types in particular). It is always safe to set this option to
641 off, but this introduces a slight performance penalty. The default
644 * Python API Improvements
646 ** GDB provides the new class gdb.LazyString. This is useful in
647 some pretty-printing cases. The new method gdb.Value.lazy_string
648 provides a simple way to create objects of this type.
650 ** The fields returned by gdb.Type.fields now have an
651 `is_base_class' attribute.
653 ** The new method gdb.Type.range returns the range of an array type.
655 ** The new method gdb.parse_and_eval can be used to parse and
656 evaluate an expression.
661 Define a trace state variable.
664 Get the current value of a trace state variable.
667 Set desired tracing behavior upon disconnection.
670 Set the trace buffer to be linear or circular.
673 Get data about the tracepoints currently in use.
677 Process record now works correctly with hardware watchpoints.
679 Multiple bug fixes have been made to the mips-irix port, making it
680 much more reliable. In particular:
681 - Debugging threaded applications is now possible again. Previously,
682 GDB would hang while starting the program, or while waiting for
683 the program to stop at a breakpoint.
684 - Attaching to a running process no longer hangs.
685 - An error occurring while loading a core file has been fixed.
686 - Changing the value of the PC register now works again. This fixes
687 problems observed when using the "jump" command, or when calling
688 a function from GDB, or even when assigning a new value to $pc.
689 - With the "finish" and "return" commands, the return value for functions
690 returning a small array is now correctly printed.
691 - It is now possible to break on shared library code which gets executed
692 during a shared library init phase (code executed while executing
693 their .init section). Previously, the breakpoint would have no effect.
694 - GDB is now able to backtrace through the signal handler for
695 non-threaded programs.
697 PIE (Position Independent Executable) programs debugging is now supported.
698 This includes debugging execution of PIC (Position Independent Code) shared
699 libraries although for that, it should be possible to run such libraries as an
702 *** Changes in GDB 7.0
704 * GDB now has an interface for JIT compilation. Applications that
705 dynamically generate code can create symbol files in memory and register
706 them with GDB. For users, the feature should work transparently, and
707 for JIT developers, the interface is documented in the GDB manual in the
708 "JIT Compilation Interface" chapter.
710 * Tracepoints may now be conditional. The syntax is as for
711 breakpoints; either an "if" clause appended to the "trace" command,
712 or the "condition" command is available. GDB sends the condition to
713 the target for evaluation using the same bytecode format as is used
714 for tracepoint actions.
716 * The disassemble command now supports: an optional /r modifier, print the
717 raw instructions in hex as well as in symbolic form, and an optional /m
718 modifier to print mixed source+assembly.
720 * Process record and replay
722 In a architecture environment that supports ``process record and
723 replay'', ``process record and replay'' target can record a log of
724 the process execution, and replay it with both forward and reverse
727 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
728 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
729 set execution-direction {forward|reverse}, for targets that support
732 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
733 feature is available with a native GDB running on kernel version
736 * GDB now has support for multi-byte and wide character sets on the
737 target. Strings whose character type is wchar_t, char16_t, or
738 char32_t are now correctly printed. GDB supports wide- and unicode-
739 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
740 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
741 `printf'. This feature requires iconv to work properly; if your
742 system does not have a working iconv, GDB can use GNU libiconv. See
743 the installation instructions for more information.
745 * GDB now supports automatic retrieval of shared library files from
746 remote targets. To use this feature, specify a system root that begins
747 with the `remote:' prefix, either via the `set sysroot' command or via
748 the `--with-sysroot' configure-time option.
750 * "info sharedlibrary" now takes an optional regex of libraries to show,
751 and it now reports if a shared library has no debugging information.
753 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
754 now complete on file names.
756 * When completing in expressions, gdb will attempt to limit
757 completions to allowable structure or union fields, where appropriate.
758 For instance, consider:
760 # struct example { int f1; double f2; };
761 # struct example variable;
764 If the user types TAB at the end of this command line, the available
765 completions will be "f1" and "f2".
767 * Inlined functions are now supported. They show up in backtraces, and
768 the "step", "next", and "finish" commands handle them automatically.
770 * GDB now supports the token-splicing (##) and stringification (#)
771 operators when expanding macros. It also supports variable-arity
774 * GDB now supports inspecting extra signal information, exported by
775 the new $_siginfo convenience variable. The feature is currently
776 implemented on linux ARM, i386 and amd64.
778 * GDB can now display the VFP floating point registers and NEON vector
779 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
780 can provide these registers (requires Linux 2.6.30 or later). Remote
781 and simulator targets may also provide them.
786 Search memory for a sequence of bytes.
789 Turn off `+'/`-' protocol acknowledgments to permit more efficient
790 operation over reliable transport links. Use of this packet is
791 controlled by the `set remote noack-packet' command.
794 Kill the process with the specified process ID. Use this in preference
795 to `k' when multiprocess protocol extensions are supported.
798 Obtains additional operating system information
802 Read or write additional signal information.
804 * Removed remote protocol undocumented extension
806 An undocumented extension to the remote protocol's `S' stop reply
807 packet that permited the stub to pass a process id was removed.
808 Remote servers should use the `T' stop reply packet instead.
810 * GDB now supports multiple function calling conventions according to the
811 DWARF-2 DW_AT_calling_convention function attribute.
813 * The SH target utilizes the aforementioned change to distinguish between gcc
814 and Renesas calling convention. It also adds the new CLI commands
815 `set/show sh calling-convention'.
817 * GDB can now read compressed debug sections, as produced by GNU gold
818 with the --compress-debug-sections=zlib flag.
820 * 64-bit core files are now supported on AIX.
822 * Thread switching is now supported on Tru64.
824 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
825 which will be allocated using malloc later in program execution.
827 * The qXfer:libraries:read remote procotol packet now allows passing a
828 list of section offsets.
830 * On GNU/Linux, GDB can now attach to stopped processes. Several race
831 conditions handling signals delivered during attach or thread creation
832 have also been fixed.
834 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
835 From the user's standpoint, all unqualified instances of True and False
836 are treated as the standard definitions, regardless of context.
838 * GDB now parses C++ symbol and type names more flexibly. For
841 template<typename T> class C { };
844 GDB will now correctly handle all of:
846 ptype C<char const *>
848 ptype C<const char *>
851 * New features in the GDB remote stub, gdbserver
853 - The "--wrapper" command-line argument tells gdbserver to use a
854 wrapper program to launch programs for debugging.
856 - On PowerPC and S/390 targets, it is now possible to use a single
857 gdbserver executable to debug both 32-bit and 64-bit programs.
858 (This requires gdbserver itself to be built as a 64-bit executable.)
860 - gdbserver uses the new noack protocol mode for TCP connections to
861 reduce communications latency, if also supported and enabled in GDB.
863 - Support for the sparc64-linux-gnu target is now included in
866 - The amd64-linux build of gdbserver now supports debugging both
867 32-bit and 64-bit programs.
869 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
870 now support hardware watchpoints, and will use them automatically
875 GDB now has support for scripting using Python. Whether this is
876 available is determined at configure time.
878 New GDB commands can now be written in Python.
880 * Ada tasking support
882 Ada tasks can now be inspected in GDB. The following commands have
886 Print the list of Ada tasks.
888 Print detailed information about task number N.
890 Print the task number of the current task.
892 Switch the context of debugging to task number N.
894 * Support for user-defined prefixed commands. The "define" command can
895 add new commands to existing prefixes, e.g. "target".
897 * Multi-inferior, multi-process debugging.
899 GDB now has generalized support for multi-inferior debugging. See
900 "Debugging Multiple Inferiors" in the manual for more information.
901 Although availability still depends on target support, the command
902 set is more uniform now. The GNU/Linux specific multi-forks support
903 has been migrated to this new framework. This implied some user
904 visible changes; see "New commands" and also "Removed commands"
907 * Target descriptions can now describe the target OS ABI. See the
908 "Target Description Format" section in the user manual for more
911 * Target descriptions can now describe "compatible" architectures
912 to indicate that the target can execute applications for a different
913 architecture in addition to those for the main target architecture.
914 See the "Target Description Format" section in the user manual for
917 * Multi-architecture debugging.
919 GDB now includes general supports for debugging applications on
920 hybrid systems that use more than one single processor architecture
921 at the same time. Each such hybrid architecture still requires
922 specific support to be added. The only hybrid architecture supported
923 in this version of GDB is the Cell Broadband Engine.
925 * GDB now supports integrated debugging of Cell/B.E. applications that
926 use both the PPU and SPU architectures. To enable support for hybrid
927 Cell/B.E. debugging, you need to configure GDB to support both the
928 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
929 --enable-targets configure option.
931 * Non-stop mode debugging.
933 For some targets, GDB now supports an optional mode of operation in
934 which you can examine stopped threads while other threads continue
935 to execute freely. This is referred to as non-stop mode, with the
936 old mode referred to as all-stop mode. See the "Non-Stop Mode"
937 section in the user manual for more information.
939 To be able to support remote non-stop debugging, a remote stub needs
940 to implement the non-stop mode remote protocol extensions, as
941 described in the "Remote Non-Stop" section of the user manual. The
942 GDB remote stub, gdbserver, has been adjusted to support these
943 extensions on linux targets.
945 * New commands (for set/show, see "New options" below)
947 catch syscall [NAME(S) | NUMBER(S)]
948 Catch system calls. Arguments, which should be names of system
949 calls or their numbers, mean catch only those syscalls. Without
950 arguments, every syscall will be caught. When the inferior issues
951 any of the specified syscalls, GDB will stop and announce the system
952 call, both when it is called and when its call returns. This
953 feature is currently available with a native GDB running on the
954 Linux Kernel, under the following architectures: x86, x86_64,
955 PowerPC and PowerPC64.
957 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
959 Search memory for a sequence of bytes.
961 maint set python print-stack
962 maint show python print-stack
963 Show a stack trace when an error is encountered in a Python script.
966 Invoke CODE by passing it to the Python interpreter.
971 These allow macros to be defined, undefined, and listed
975 Show operating system information about processes.
978 List the inferiors currently under GDB's control.
981 Switch focus to inferior number NUM.
984 Detach from inferior number NUM.
987 Kill inferior number NUM.
992 show spu stop-on-load
993 Control whether to stop for new SPE threads during Cell/B.E. debugging.
995 set spu auto-flush-cache
996 show spu auto-flush-cache
997 Control whether to automatically flush the software-managed cache
998 during Cell/B.E. debugging.
1000 set sh calling-convention
1001 show sh calling-convention
1002 Control the calling convention used when calling SH target functions.
1005 show debug timestamp
1006 Control display of timestamps with GDB debugging output.
1008 set disassemble-next-line
1009 show disassemble-next-line
1010 Control display of disassembled source lines or instructions when
1013 set remote noack-packet
1014 show remote noack-packet
1015 Set/show the use of remote protocol QStartNoAckMode packet. See above
1016 under "New remote packets."
1018 set remote query-attached-packet
1019 show remote query-attached-packet
1020 Control use of remote protocol `qAttached' (query-attached) packet.
1022 set remote read-siginfo-object
1023 show remote read-siginfo-object
1024 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1027 set remote write-siginfo-object
1028 show remote write-siginfo-object
1029 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1032 set remote reverse-continue
1033 show remote reverse-continue
1034 Control use of remote protocol 'bc' (reverse-continue) packet.
1036 set remote reverse-step
1037 show remote reverse-step
1038 Control use of remote protocol 'bs' (reverse-step) packet.
1040 set displaced-stepping
1041 show displaced-stepping
1042 Control displaced stepping mode. Displaced stepping is a way to
1043 single-step over breakpoints without removing them from the debuggee.
1044 Also known as "out-of-line single-stepping".
1047 show debug displaced
1048 Control display of debugging info for displaced stepping.
1050 maint set internal-error
1051 maint show internal-error
1052 Control what GDB does when an internal error is detected.
1054 maint set internal-warning
1055 maint show internal-warning
1056 Control what GDB does when an internal warning is detected.
1061 Use a wrapper program to launch programs for debugging.
1063 set multiple-symbols (all|ask|cancel)
1064 show multiple-symbols
1065 The value of this variable can be changed to adjust the debugger behavior
1066 when an expression or a breakpoint location contains an ambiguous symbol
1067 name (an overloaded function name, for instance).
1069 set breakpoint always-inserted
1070 show breakpoint always-inserted
1071 Keep breakpoints always inserted in the target, as opposed to inserting
1072 them when resuming the target, and removing them when the target stops.
1073 This option can improve debugger performance on slow remote targets.
1075 set arm fallback-mode (arm|thumb|auto)
1076 show arm fallback-mode
1077 set arm force-mode (arm|thumb|auto)
1079 These commands control how ARM GDB determines whether instructions
1080 are ARM or Thumb. The default for both settings is auto, which uses
1081 the current CPSR value for instructions without symbols; previous
1082 versions of GDB behaved as if "set arm fallback-mode arm".
1084 set disable-randomization
1085 show disable-randomization
1086 Standalone programs run with the virtual address space randomization enabled
1087 by default on some platforms. This option keeps the addresses stable across
1088 multiple debugging sessions.
1092 Control whether other threads are stopped or not when some thread hits
1097 Requests that asynchronous execution is enabled in the target, if available.
1098 In this case, it's possible to resume target in the background, and interact
1099 with GDB while the target is running. "show target-async" displays the
1100 current state of asynchronous execution of the target.
1102 set target-wide-charset
1103 show target-wide-charset
1104 The target-wide-charset is the name of the character set that GDB
1105 uses when printing characters whose type is wchar_t.
1107 set tcp auto-retry (on|off)
1109 set tcp connect-timeout
1110 show tcp connect-timeout
1111 These commands allow GDB to retry failed TCP connections to a remote stub
1112 with a specified timeout period; this is useful if the stub is launched
1113 in parallel with GDB but may not be ready to accept connections immediately.
1115 set libthread-db-search-path
1116 show libthread-db-search-path
1117 Control list of directories which GDB will search for appropriate
1120 set schedule-multiple (on|off)
1121 show schedule-multiple
1122 Allow GDB to resume all threads of all processes or only threads of
1123 the current process.
1127 Use more aggressive caching for accesses to the stack. This improves
1128 performance of remote debugging (particularly backtraces) without
1129 affecting correctness.
1131 set interactive-mode (on|off|auto)
1132 show interactive-mode
1133 Control whether GDB runs in interactive mode (on) or not (off).
1134 When in interactive mode, GDB waits for the user to answer all
1135 queries. Otherwise, GDB does not wait and assumes the default
1136 answer. When set to auto (the default), GDB determines which
1137 mode to use based on the stdin settings.
1142 For program forks, this is replaced by the new more generic `info
1143 inferiors' command. To list checkpoints, you can still use the
1144 `info checkpoints' command, which was an alias for the `info forks'
1148 Replaced by the new `inferior' command. To switch between
1149 checkpoints, you can still use the `restart' command, which was an
1150 alias for the `fork' command.
1153 This is removed, since some targets don't have a notion of
1154 processes. To switch between processes, you can still use the
1155 `inferior' command using GDB's own inferior number.
1158 For program forks, this is replaced by the new more generic `kill
1159 inferior' command. To delete a checkpoint, you can still use the
1160 `delete checkpoint' command, which was an alias for the `delete
1164 For program forks, this is replaced by the new more generic `detach
1165 inferior' command. To detach a checkpoint, you can still use the
1166 `detach checkpoint' command, which was an alias for the `detach
1169 * New native configurations
1171 x86/x86_64 Darwin i[34567]86-*-darwin*
1173 x86_64 MinGW x86_64-*-mingw*
1177 Lattice Mico32 lm32-*
1178 x86 DICOS i[34567]86-*-dicos*
1179 x86_64 DICOS x86_64-*-dicos*
1182 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1183 (mingw32ce) debugging.
1189 These commands were actually not implemented on any target.
1191 *** Changes in GDB 6.8
1193 * New native configurations
1195 NetBSD/hppa hppa*-*netbsd*
1196 Xtensa GNU/Linux xtensa*-*-linux*
1200 NetBSD/hppa hppa*-*-netbsd*
1201 Xtensa GNU/Lunux xtensa*-*-linux*
1203 * Change in command line behavior -- corefiles vs. process ids.
1205 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1206 attaching to process NUMBER fails, GDB no longer attempts to open a
1207 core file named NUMBER. Attaching to a program using the -c option
1208 is no longer supported. Instead, use the '-p' or '--pid' options.
1210 * GDB can now be built as a native debugger for debugging Windows x86
1211 (mingw32) Portable Executable (PE) programs.
1213 * Pending breakpoints no longer change their number when their address
1216 * GDB now supports breakpoints with multiple locations,
1217 including breakpoints on C++ constructors, inside C++ templates,
1218 and in inlined functions.
1220 * GDB's ability to debug optimized code has been improved. GDB more
1221 accurately identifies function bodies and lexical blocks that occupy
1222 more than one contiguous range of addresses.
1224 * Target descriptions can now describe registers for PowerPC.
1226 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1227 registers on PowerPC targets.
1229 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1230 targets even when the libthread_db library is not available.
1232 * The GDB remote stub, gdbserver, now supports the new file transfer
1233 commands (remote put, remote get, and remote delete).
1235 * The GDB remote stub, gdbserver, now supports run and attach in
1236 extended-remote mode.
1238 * hppa*64*-*-hpux11* target broken
1239 The debugger is unable to start a program and fails with the following
1240 error: "Error trying to get information about dynamic linker".
1241 The gdb-6.7 release is also affected.
1243 * GDB now supports the --enable-targets= configure option to allow
1244 building a single GDB executable that supports multiple remote
1245 target architectures.
1247 * GDB now supports debugging C and C++ programs which use the
1248 Decimal Floating Point extension. In addition, the PowerPC target
1249 now has a set of pseudo-registers to inspect decimal float values
1250 stored in two consecutive float registers.
1252 * The -break-insert MI command can optionally create pending
1255 * Improved support for debugging Ada
1256 Many improvements to the Ada language support have been made. These
1258 - Better support for Ada2005 interface types
1259 - Improved handling of arrays and slices in general
1260 - Better support for Taft-amendment types
1261 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1263 - Improved command completion in Ada
1266 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1271 set print frame-arguments (all|scalars|none)
1272 show print frame-arguments
1273 The value of this variable can be changed to control which argument
1274 values should be printed by the debugger when displaying a frame.
1279 Transfer files to and from a remote target, and delete remote files.
1286 Transfer files to and from a remote target, and delete remote files.
1288 * New remote packets
1295 Open, close, read, write, and delete files on the remote system.
1298 Attach to an existing process on the remote system, in extended-remote
1302 Run a new process on the remote system, in extended-remote mode.
1304 *** Changes in GDB 6.7
1306 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1307 bfd, libiberty and opcodes, as revealed by static analysis donated by
1308 Coverity, Inc. (http://scan.coverity.com).
1310 * When looking up multiply-defined global symbols, GDB will now prefer the
1311 symbol definition in the current shared library if it was built using the
1312 -Bsymbolic linker option.
1314 * When the Text User Interface (TUI) is not configured, GDB will now
1315 recognize the -tui command-line option and print a message that the TUI
1318 * The GDB remote stub, gdbserver, now has lower overhead for high
1319 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1321 * GDB for MIPS targets now autodetects whether a remote target provides
1322 32-bit or 64-bit register values.
1324 * Support for C++ member pointers has been improved.
1326 * GDB now understands XML target descriptions, which specify the
1327 target's overall architecture. GDB can read a description from
1328 a local file or over the remote serial protocol.
1330 * Vectors of single-byte data use a new integer type which is not
1331 automatically displayed as character or string data.
1333 * The /s format now works with the print command. It displays
1334 arrays of single-byte integers and pointers to single-byte integers
1337 * Target descriptions can now describe target-specific registers,
1338 for architectures which have implemented the support (currently
1339 only ARM, M68K, and MIPS).
1341 * GDB and the GDB remote stub, gdbserver, now support the XScale
1344 * The GDB remote stub, gdbserver, has been updated to support
1345 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1346 has been rewritten to use the standard GDB remote protocol.
1348 * GDB can now step into C++ functions which are called through thunks.
1350 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1352 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1353 layout. It also supports a TextSeg= and DataSeg= response when only
1354 segment base addresses (rather than offsets) are available.
1356 * The /i format now outputs any trailing branch delay slot instructions
1357 immediately following the last instruction within the count specified.
1359 * The GDB remote protocol "T" stop reply packet now supports a
1360 "library" response. Combined with the new "qXfer:libraries:read"
1361 packet, this response allows GDB to debug shared libraries on targets
1362 where the operating system manages the list of loaded libraries (e.g.
1363 Windows and SymbianOS).
1365 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1366 (DLLs) on Windows and Windows CE targets.
1368 * GDB now supports a faster verification that a .debug file matches its binary
1369 according to its build-id signature, if the signature is present.
1375 Enable or disable hardware flow control (RTS/CTS) on the serial port
1376 when debugging using remote targets.
1378 set mem inaccessible-by-default
1379 show mem inaccessible-by-default
1380 If the target supplies a memory map, for instance via the remote
1381 protocol's "qXfer:memory-map:read" packet, setting this variable
1382 prevents GDB from accessing memory outside the memory map. This
1383 is useful for targets with memory mapped registers or which react
1384 badly to accesses of unmapped address space.
1386 set breakpoint auto-hw
1387 show breakpoint auto-hw
1388 If the target supplies a memory map, for instance via the remote
1389 protocol's "qXfer:memory-map:read" packet, setting this variable
1390 lets GDB use hardware breakpoints automatically for memory regions
1391 where it can not use software breakpoints. This covers both the
1392 "break" command and internal breakpoints used for other commands
1393 including "next" and "finish".
1396 catch exception unhandled
1397 Stop the program execution when Ada exceptions are raised.
1400 Stop the program execution when an Ada assertion failed.
1404 Set an alternate system root for target files. This is a more
1405 general version of "set solib-absolute-prefix", which is now
1406 an alias to "set sysroot".
1409 Provide extended SPU facility status information. This set of
1410 commands is available only when debugging the Cell/B.E. SPU
1413 * New native configurations
1415 OpenBSD/sh sh*-*openbsd*
1418 unset tdesc filename
1420 Use the specified local file as an XML target description, and do
1421 not query the target for its built-in description.
1425 OpenBSD/sh sh*-*-openbsd*
1426 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1427 Toshiba Media Processor mep-elf
1429 * New remote packets
1432 Ignore the specified signals; pass them directly to the debugged program
1433 without stopping other threads or reporting them to GDB.
1435 qXfer:features:read:
1436 Read an XML target description from the target, which describes its
1441 Read or write contents of an spufs file on the target system. These
1442 packets are available only on the Cell/B.E. SPU architecture.
1444 qXfer:libraries:read:
1445 Report the loaded shared libraries. Combined with new "T" packet
1446 response, this packet allows GDB to debug shared libraries on
1447 targets where the operating system manages the list of loaded
1448 libraries (e.g. Windows and SymbianOS).
1452 Support for these obsolete configurations has been removed.
1460 i[34567]86-*-lynxos*
1461 i[34567]86-*-netware*
1462 i[34567]86-*-sco3.2v5*
1463 i[34567]86-*-sco3.2v4*
1465 i[34567]86-*-sysv4.2*
1468 i[34567]86-*-unixware2*
1469 i[34567]86-*-unixware*
1478 * Other removed features
1485 Various m68k-only ROM monitors.
1492 Various Renesas ROM monitors and debugging interfaces for SH and
1497 Support for a Macraigor serial interface to on-chip debugging.
1498 GDB does not directly support the newer parallel or USB
1503 A debug information format. The predecessor to DWARF 2 and
1504 DWARF 3, which are still supported.
1506 Support for the HP aCC compiler on HP-UX/PA-RISC
1508 SOM-encapsulated symbolic debugging information, automatic
1509 invocation of pxdb, and the aCC custom C++ ABI. This does not
1510 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1511 with aCC can still be debugged on an assembly level.
1513 MIPS ".pdr" sections
1515 A MIPS-specific format used to describe stack frame layout
1516 in debugging information.
1520 GDB could work with an older version of Guile to debug
1521 the interpreter and Scheme programs running in it.
1523 set mips stack-arg-size
1524 set mips saved-gpreg-size
1526 Use "set mips abi" to control parameter passing for MIPS.
1528 *** Changes in GDB 6.6
1533 Cell Broadband Engine SPU spu-elf
1535 * GDB can now be configured as a cross-debugger targeting native Windows
1536 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1537 running on a Windows system over TCP/IP to debug Windows programs.
1539 * The GDB remote stub, gdbserver, has been updated to support Windows and
1540 Cygwin debugging. Both single-threaded and multi-threaded programs are
1543 * The "set trust-readonly-sections" command works again. This command was
1544 broken in GDB 6.3, 6.4, and 6.5.
1546 * The "load" command now supports writing to flash memory, if the remote
1547 stub provides the required support.
1549 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1550 longer requires symbolic debug information (e.g. DWARF-2).
1555 unset substitute-path
1556 show substitute-path
1557 Manage a list of substitution rules that GDB uses to rewrite the name
1558 of the directories where the sources are located. This can be useful
1559 for instance when the sources were moved to a different location
1560 between compilation and debugging.
1564 Print each CLI command as it is executed. Each command is prefixed with
1565 a number of `+' symbols representing the nesting depth.
1566 The source command now has a `-v' option to enable the same feature.
1570 The ARM Demon monitor support (RDP protocol, "target rdp").
1572 Kernel Object Display, an embedded debugging feature which only worked with
1573 an obsolete version of Cisco IOS.
1575 The 'set download-write-size' and 'show download-write-size' commands.
1577 * New remote packets
1580 Tell a stub about GDB client features, and request remote target features.
1581 The first feature implemented is PacketSize, which allows the target to
1582 specify the size of packets it can handle - to minimize the number of
1583 packets required and improve performance when connected to a remote
1587 Fetch an OS auxilliary vector from the remote stub. This packet is a
1588 more efficient replacement for qPart:auxv:read.
1590 qXfer:memory-map:read:
1591 Fetch a memory map from the remote stub, including information about
1592 RAM, ROM, and flash memory devices.
1597 Erase and program a flash memory device.
1599 * Removed remote packets
1602 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1603 used it, and only gdbserver implemented it.
1605 *** Changes in GDB 6.5
1609 Renesas M32C/M16C m32c-elf
1611 Morpho Technologies ms1 ms1-elf
1615 init-if-undefined Initialize a convenience variable, but
1616 only if it doesn't already have a value.
1618 The following commands are presently only implemented for native GNU/Linux:
1620 checkpoint Save a snapshot of the program state.
1622 restart <n> Return the program state to a
1623 previously saved state.
1625 info checkpoints List currently saved checkpoints.
1627 delete-checkpoint <n> Delete a previously saved checkpoint.
1629 set|show detach-on-fork Tell gdb whether to detach from a newly
1630 forked process, or to keep debugging it.
1632 info forks List forks of the user program that
1633 are available to be debugged.
1635 fork <n> Switch to debugging one of several
1636 forks of the user program that are
1637 available to be debugged.
1639 delete-fork <n> Delete a fork from the list of forks
1640 that are available to be debugged (and
1641 kill the forked process).
1643 detach-fork <n> Delete a fork from the list of forks
1644 that are available to be debugged (and
1645 allow the process to continue).
1649 Morpho Technologies ms2 ms1-elf
1651 * Improved Windows host support
1653 GDB now builds as a cross debugger hosted on i686-mingw32, including
1654 native console support, and remote communications using either
1655 network sockets or serial ports.
1657 * Improved Modula-2 language support
1659 GDB can now print most types in the Modula-2 syntax. This includes:
1660 basic types, set types, record types, enumerated types, range types,
1661 pointer types and ARRAY types. Procedure var parameters are correctly
1662 printed and hexadecimal addresses and character constants are also
1663 written in the Modula-2 syntax. Best results can be obtained by using
1664 GNU Modula-2 together with the -gdwarf-2 command line option.
1668 The ARM rdi-share module.
1670 The Netware NLM debug server.
1672 *** Changes in GDB 6.4
1674 * New native configurations
1676 OpenBSD/arm arm*-*-openbsd*
1677 OpenBSD/mips64 mips64-*-openbsd*
1681 Morpho Technologies ms1 ms1-elf
1683 * New command line options
1685 --batch-silent As for --batch, but totally silent.
1686 --return-child-result The debugger will exist with the same value
1687 the child (debugged) program exited with.
1688 --eval-command COMMAND, -ex COMMAND
1689 Execute a single GDB CLI command. This may be
1690 specified multiple times and in conjunction
1691 with the --command (-x) option.
1693 * Deprecated commands removed
1695 The following commands, that were deprecated in 2000, have been
1699 set|show arm disassembly-flavor set|show arm disassembler
1700 othernames set arm disassembler
1701 set|show remotedebug set|show debug remote
1702 set|show archdebug set|show debug arch
1703 set|show eventdebug set|show debug event
1706 * New BSD user-level threads support
1708 It is now possible to debug programs using the user-level threads
1709 library on OpenBSD and FreeBSD. Currently supported (target)
1712 FreeBSD/amd64 x86_64-*-freebsd*
1713 FreeBSD/i386 i386-*-freebsd*
1714 OpenBSD/i386 i386-*-openbsd*
1716 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1717 are not yet supported.
1719 * New support for Matsushita MN10300 w/sim added
1720 (Work in progress). mn10300-elf.
1722 * REMOVED configurations and files
1724 VxWorks and the XDR protocol *-*-vxworks
1725 Motorola MCORE mcore-*-*
1726 National Semiconductor NS32000 ns32k-*-*
1728 * New "set print array-indexes" command
1730 After turning this setting "on", GDB prints the index of each element
1731 when displaying arrays. The default is "off" to preserve the previous
1734 * VAX floating point support
1736 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1738 * User-defined command support
1740 In addition to using $arg0..$arg9 for argument passing, it is now possible
1741 to use $argc to determine now many arguments have been passed. See the
1742 section on user-defined commands in the user manual for more information.
1744 *** Changes in GDB 6.3:
1746 * New command line option
1748 GDB now accepts -l followed by a number to set the timeout for remote
1751 * GDB works with GCC -feliminate-dwarf2-dups
1753 GDB now supports a more compact representation of DWARF-2 debug
1754 information using DW_FORM_ref_addr references. These are produced
1755 by GCC with the option -feliminate-dwarf2-dups and also by some
1756 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1757 to use -feliminate-dwarf2-dups.
1759 * Internationalization
1761 When supported by the host system, GDB will be built with
1762 internationalization (libintl). The task of marking up the sources is
1763 continued, we're looking forward to our first translation.
1767 Initial support for debugging programs compiled with the GNAT
1768 implementation of the Ada programming language has been integrated
1769 into GDB. In this release, support is limited to expression evaluation.
1771 * New native configurations
1773 GNU/Linux/m32r m32r-*-linux-gnu
1777 GDB's remote protocol now includes support for the 'p' packet. This
1778 packet is used to fetch individual registers from a remote inferior.
1780 * END-OF-LIFE registers[] compatibility module
1782 GDB's internal register infrastructure has been completely rewritten.
1783 The new infrastructure making possible the implementation of key new
1784 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1787 GDB 6.3 will be the last release to include the the registers[]
1788 compatibility module that allowed out-of-date configurations to
1789 continue to work. This change directly impacts the following
1799 powerpc bdm protocol
1801 Unless there is activity to revive these configurations, they will be
1802 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1804 * OBSOLETE configurations and files
1806 Configurations that have been declared obsolete in this release have
1807 been commented out. Unless there is activity to revive these
1808 configurations, the next release of GDB will have their sources
1809 permanently REMOVED.
1818 *** Changes in GDB 6.2.1:
1820 * MIPS `break main; run' gave an heuristic-fence-post warning
1822 When attempting to run even a simple program, a warning about
1823 heuristic-fence-post being hit would be reported. This problem has
1826 * MIPS IRIX 'long double' crashed GDB
1828 When examining a long double variable, GDB would get a segmentation
1829 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1830 IRIX long double values).
1834 A bug in the VAX stack code was causing problems with the "next"
1835 command. This problem has been fixed.
1837 *** Changes in GDB 6.2:
1839 * Fix for ``many threads''
1841 On GNU/Linux systems that use the NPTL threads library, a program
1842 rapidly creating and deleting threads would confuse GDB leading to the
1845 ptrace: No such process.
1846 thread_db_get_info: cannot get thread info: generic error
1848 This problem has been fixed.
1850 * "-async" and "-noasync" options removed.
1852 Support for the broken "-noasync" option has been removed (it caused
1855 * New ``start'' command.
1857 This command runs the program until the begining of the main procedure.
1859 * New BSD Kernel Data Access Library (libkvm) interface
1861 Using ``target kvm'' it is now possible to debug kernel core dumps and
1862 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1863 platforms. Currently supported (native-only) configurations are:
1865 FreeBSD/amd64 x86_64-*-freebsd*
1866 FreeBSD/i386 i?86-*-freebsd*
1867 NetBSD/i386 i?86-*-netbsd*
1868 NetBSD/m68k m68*-*-netbsd*
1869 NetBSD/sparc sparc-*-netbsd*
1870 OpenBSD/amd64 x86_64-*-openbsd*
1871 OpenBSD/i386 i?86-*-openbsd*
1872 OpenBSD/m68k m68*-openbsd*
1873 OpenBSD/sparc sparc-*-openbsd*
1875 * Signal trampoline code overhauled
1877 Many generic problems with GDB's signal handling code have been fixed.
1878 These include: backtraces through non-contiguous stacks; recognition
1879 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1880 call; backtrace through a signal trampoline; step into and out of
1881 signal handlers; and single-stepping in the signal trampoline.
1883 Please note that kernel bugs are a limiting factor here. These
1884 features have been shown to work on an s390 GNU/Linux system that
1885 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1887 * Cygwin support for DWARF 2 added.
1889 * New native configurations
1891 GNU/Linux/hppa hppa*-*-linux*
1892 OpenBSD/hppa hppa*-*-openbsd*
1893 OpenBSD/m68k m68*-*-openbsd*
1894 OpenBSD/m88k m88*-*-openbsd*
1895 OpenBSD/powerpc powerpc-*-openbsd*
1896 NetBSD/vax vax-*-netbsd*
1897 OpenBSD/vax vax-*-openbsd*
1899 * END-OF-LIFE frame compatibility module
1901 GDB's internal frame infrastructure has been completely rewritten.
1902 The new infrastructure making it possible to support key new features
1903 including DWARF 2 Call Frame Information. To aid in the task of
1904 migrating old configurations to this new infrastructure, a
1905 compatibility module, that allowed old configurations to continue to
1906 work, was also included.
1908 GDB 6.2 will be the last release to include this frame compatibility
1909 module. This change directly impacts the following configurations:
1919 Unless there is activity to revive these configurations, they will be
1920 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1922 * REMOVED configurations and files
1924 Sun 3, running SunOS 3 m68*-*-sunos3*
1925 Sun 3, running SunOS 4 m68*-*-sunos4*
1926 Sun 2, running SunOS 3 m68000-*-sunos3*
1927 Sun 2, running SunOS 4 m68000-*-sunos4*
1928 Motorola 680x0 running LynxOS m68*-*-lynxos*
1929 AT&T 3b1/Unix pc m68*-att-*
1930 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1931 decstation mips-dec-* mips-little-*
1932 riscos mips-*-riscos* mips-*-sysv*
1933 sonymips mips-sony-*
1934 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1936 *** Changes in GDB 6.1.1:
1938 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1940 The TUI (Text-mode User Interface) is now built as part of a default
1941 GDB configuration. It is enabled by either selecting the TUI with the
1942 command line option "-i=tui" or by running the separate "gdbtui"
1943 program. For more information on the TUI, see the manual "Debugging
1946 * Pending breakpoint support (also included in GDB 6.1)
1948 Support has been added to allow you to specify breakpoints in shared
1949 libraries that have not yet been loaded. If a breakpoint location
1950 cannot be found, and the "breakpoint pending" option is set to auto,
1951 GDB queries you if you wish to make the breakpoint pending on a future
1952 shared-library load. If and when GDB resolves the breakpoint symbol,
1953 the pending breakpoint is removed as one or more regular breakpoints
1956 Pending breakpoints are very useful for GCJ Java debugging.
1958 * Fixed ISO-C build problems
1960 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1961 non ISO-C code that stopped them being built using a more strict ISO-C
1962 compiler (e.g., IBM's C compiler).
1964 * Fixed build problem on IRIX 5
1966 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1967 wasn't able to compile compile on an IRIX 5 system.
1969 * Added execute permission to gdb/gdbserver/configure
1971 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1972 permission. This bug would cause configure to fail on a number of
1973 systems (Solaris, IRIX). Ref: server/519.
1975 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1977 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1978 has been updated to use constant array sizes.
1980 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1982 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1983 its generated DWARF Call Frame Info. This encoding was causing GDB to
1984 panic, that panic has been fixed. Ref: gdb/1628.
1986 * Fixed a problem when examining parameters in shared library code.
1988 When examining parameters in optimized shared library code generated
1989 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1990 not available''. GDB now correctly displays the variable's value.
1992 *** Changes in GDB 6.1:
1994 * Removed --with-mmalloc
1996 Support for the mmalloc memory manager has been removed, as it
1997 conflicted with the internal gdb byte cache.
1999 * Changes in AMD64 configurations
2001 The AMD64 target now includes the %cs and %ss registers. As a result
2002 the AMD64 remote protocol has changed; this affects the floating-point
2003 and SSE registers. If you rely on those registers for your debugging,
2004 you should upgrade gdbserver on the remote side.
2006 * Revised SPARC target
2008 The SPARC target has been completely revised, incorporating the
2009 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2010 support for LynxOS and SunOS 4 has been dropped. Calling functions
2011 from within GDB on operating systems with a non-executable stack
2012 (Solaris, OpenBSD) now works.
2016 GDB has a new C++ demangler which does a better job on the mangled
2017 names generated by current versions of g++. It also runs faster, so
2018 with this and other changes gdb should now start faster on large C++
2021 * DWARF 2 Location Expressions
2023 GDB support for location expressions has been extended to support function
2024 arguments and frame bases. Older versions of GDB could crash when they
2027 * C++ nested types and namespaces
2029 GDB's support for nested types and namespaces in C++ has been
2030 improved, especially if you use the DWARF 2 debugging format. (This
2031 is the default for recent versions of GCC on most platforms.)
2032 Specifically, if you have a class "Inner" defined within a class or
2033 namespace "Outer", then GDB realizes that the class's name is
2034 "Outer::Inner", not simply "Inner". This should greatly reduce the
2035 frequency of complaints about not finding RTTI symbols. In addition,
2036 if you are stopped at inside of a function defined within a namespace,
2037 GDB modifies its name lookup accordingly.
2039 * New native configurations
2041 NetBSD/amd64 x86_64-*-netbsd*
2042 OpenBSD/amd64 x86_64-*-openbsd*
2043 OpenBSD/alpha alpha*-*-openbsd*
2044 OpenBSD/sparc sparc-*-openbsd*
2045 OpenBSD/sparc64 sparc64-*-openbsd*
2047 * New debugging protocols
2049 M32R with SDI protocol m32r-*-elf*
2051 * "set prompt-escape-char" command deleted.
2053 The command "set prompt-escape-char" has been deleted. This command,
2054 and its very obscure effet on GDB's prompt, was never documented,
2055 tested, nor mentioned in the NEWS file.
2057 * OBSOLETE configurations and files
2059 Configurations that have been declared obsolete in this release have
2060 been commented out. Unless there is activity to revive these
2061 configurations, the next release of GDB will have their sources
2062 permanently REMOVED.
2064 Sun 3, running SunOS 3 m68*-*-sunos3*
2065 Sun 3, running SunOS 4 m68*-*-sunos4*
2066 Sun 2, running SunOS 3 m68000-*-sunos3*
2067 Sun 2, running SunOS 4 m68000-*-sunos4*
2068 Motorola 680x0 running LynxOS m68*-*-lynxos*
2069 AT&T 3b1/Unix pc m68*-att-*
2070 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2071 decstation mips-dec-* mips-little-*
2072 riscos mips-*-riscos* mips-*-sysv*
2073 sonymips mips-sony-*
2074 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2076 * REMOVED configurations and files
2078 SGI Irix-4.x mips-sgi-irix4 or iris4
2079 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2080 Z8000 simulator z8k-zilog-none or z8ksim
2081 Matsushita MN10200 w/simulator mn10200-*-*
2082 H8/500 simulator h8500-hitachi-hms or h8500hms
2083 HP/PA running BSD hppa*-*-bsd*
2084 HP/PA running OSF/1 hppa*-*-osf*
2085 HP/PA Pro target hppa*-*-pro*
2086 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2087 386BSD i[3456]86-*-bsd*
2088 Sequent family i[3456]86-sequent-sysv4*
2089 i[3456]86-sequent-sysv*
2090 i[3456]86-sequent-bsd*
2091 SPARC running LynxOS sparc-*-lynxos*
2092 SPARC running SunOS 4 sparc-*-sunos4*
2093 Tsqware Sparclet sparclet-*-*
2094 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2096 *** Changes in GDB 6.0:
2100 Support for debugging the Objective-C programming language has been
2101 integrated into GDB.
2103 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2105 DWARF 2's Call Frame Information makes available compiler generated
2106 information that more exactly describes the program's run-time stack.
2107 By using this information, GDB is able to provide more robust stack
2110 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2111 have been updated to use a new backtrace mechanism which includes
2112 DWARF 2 CFI support.
2116 GDB's remote protocol has been extended to include support for hosted
2117 file I/O (where the remote target uses GDB's file system). See GDB's
2118 remote protocol documentation for details.
2120 * All targets using the new architecture framework.
2122 All of GDB's targets have been updated to use the new internal
2123 architecture framework. The way is now open for future GDB releases
2124 to include cross-architecture native debugging support (i386 on amd64,
2127 * GNU/Linux's Thread Local Storage (TLS)
2129 GDB now includes support for for the GNU/Linux implementation of
2130 per-thread variables.
2132 * GNU/Linux's Native POSIX Thread Library (NPTL)
2134 GDB's thread code has been updated to work with either the new
2135 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2137 * Separate debug info.
2139 GDB, in conjunction with BINUTILS, now supports a mechanism for
2140 automatically loading debug information from a separate file. Instead
2141 of shipping full debug and non-debug versions of system libraries,
2142 system integrators can now instead ship just the stripped libraries
2143 and optional debug files.
2145 * DWARF 2 Location Expressions
2147 DWARF 2 Location Expressions allow the compiler to more completely
2148 describe the location of variables (even in optimized code) to the
2151 GDB now includes preliminary support for location expressions (support
2152 for DW_OP_piece is still missing).
2156 A number of long standing bugs that caused GDB to die while starting a
2157 Java application have been fixed. GDB's Java support is now
2158 considered "useable".
2160 * GNU/Linux support for fork, vfork, and exec.
2162 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2163 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2166 * GDB supports logging output to a file
2168 There are two new commands, "set logging" and "show logging", which can be
2169 used to capture GDB's output to a file.
2171 * The meaning of "detach" has changed for gdbserver
2173 The "detach" command will now resume the application, as documented. To
2174 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2177 * d10v, m68hc11 `regs' command deprecated
2179 The `info registers' command has been updated so that it displays the
2180 registers using a format identical to the old `regs' command.
2184 A new command, "maint set profile on/off", has been added. This command can
2185 be used to enable or disable profiling while running GDB, to profile a
2186 session or a set of commands. In addition there is a new configure switch,
2187 "--enable-profiling", which will cause GDB to be compiled with profiling
2188 data, for more informative profiling results.
2190 * Default MI syntax changed to "mi2".
2192 The default MI (machine interface) syntax, enabled by the command line
2193 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2194 "mi1", can be enabled by specifying the option "-i=mi1".
2196 Support for the original "mi0" syntax (included in GDB 5.0) has been
2199 Fix for gdb/192: removed extraneous space when displaying frame level.
2200 Fix for gdb/672: update changelist is now output in mi list format.
2201 Fix for gdb/702: a -var-assign that updates the value now shows up
2202 in a subsequent -var-update.
2204 * New native configurations.
2206 FreeBSD/amd64 x86_64-*-freebsd*
2208 * Multi-arched targets.
2210 HP/PA HPUX11 hppa*-*-hpux*
2211 Renesas M32R/D w/simulator m32r-*-elf*
2213 * OBSOLETE configurations and files
2215 Configurations that have been declared obsolete in this release have
2216 been commented out. Unless there is activity to revive these
2217 configurations, the next release of GDB will have their sources
2218 permanently REMOVED.
2220 Z8000 simulator z8k-zilog-none or z8ksim
2221 Matsushita MN10200 w/simulator mn10200-*-*
2222 H8/500 simulator h8500-hitachi-hms or h8500hms
2223 HP/PA running BSD hppa*-*-bsd*
2224 HP/PA running OSF/1 hppa*-*-osf*
2225 HP/PA Pro target hppa*-*-pro*
2226 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2227 Sequent family i[3456]86-sequent-sysv4*
2228 i[3456]86-sequent-sysv*
2229 i[3456]86-sequent-bsd*
2230 Tsqware Sparclet sparclet-*-*
2231 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2233 * REMOVED configurations and files
2236 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2237 IBM AIX PS/2 i[3456]86-*-aix
2238 i386 running Mach 3.0 i[3456]86-*-mach3*
2239 i386 running Mach i[3456]86-*-mach*
2240 i386 running OSF/1 i[3456]86-*osf1mk*
2241 HP/Apollo 68k Family m68*-apollo*-sysv*,
2243 m68*-hp-bsd*, m68*-hp-hpux*
2244 Argonaut Risc Chip (ARC) arc-*-*
2245 Mitsubishi D30V d30v-*-*
2246 Fujitsu FR30 fr30-*-elf*
2247 OS/9000 i[34]86-*-os9k
2248 I960 with MON960 i960-*-coff
2250 * MIPS $fp behavior changed
2252 The convenience variable $fp, for the MIPS, now consistently returns
2253 the address of the current frame's base. Previously, depending on the
2254 context, $fp could refer to either $sp or the current frame's base
2255 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2256 The GNU Source-Level Debugger''.
2258 *** Changes in GDB 5.3:
2260 * GNU/Linux shared library multi-threaded performance improved.
2262 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2263 `/proc', in preference to `ptrace' for memory reads. This may result
2264 in an improvement in the start-up time of multi-threaded, shared
2265 library applications when run under GDB. One GDB user writes: ``loads
2266 shared libs like mad''.
2268 * ``gdbserver'' now supports multi-threaded applications on some targets
2270 Support for debugging multi-threaded applications which use
2271 the GNU/Linux LinuxThreads package has been added for
2272 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2273 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2275 * GDB now supports C/C++ preprocessor macros.
2277 GDB now expands preprocessor macro invocations in C/C++ expressions,
2278 and provides various commands for showing macro definitions and how
2281 The new command `macro expand EXPRESSION' expands any macro
2282 invocations in expression, and shows the result.
2284 The new command `show macro MACRO-NAME' shows the definition of the
2285 macro named MACRO-NAME, and where it was defined.
2287 Most compilers don't include information about macros in the debugging
2288 information by default. In GCC 3.1, for example, you need to compile
2289 your program with the options `-gdwarf-2 -g3'. If the macro
2290 information is present in the executable, GDB will read it.
2292 * Multi-arched targets.
2294 DEC Alpha (partial) alpha*-*-*
2295 DEC VAX (partial) vax-*-*
2297 National Semiconductor NS32000 (partial) ns32k-*-*
2298 Motorola 68000 (partial) m68k-*-*
2299 Motorola MCORE mcore-*-*
2303 Fujitsu FRV architecture added by Red Hat frv*-*-*
2306 * New native configurations
2308 Alpha NetBSD alpha*-*-netbsd*
2309 SH NetBSD sh*-*-netbsdelf*
2310 MIPS NetBSD mips*-*-netbsd*
2311 UltraSPARC NetBSD sparc64-*-netbsd*
2313 * OBSOLETE configurations and files
2315 Configurations that have been declared obsolete in this release have
2316 been commented out. Unless there is activity to revive these
2317 configurations, the next release of GDB will have their sources
2318 permanently REMOVED.
2320 Mitsubishi D30V d30v-*-*
2321 OS/9000 i[34]86-*-os9k
2322 IBM AIX PS/2 i[3456]86-*-aix
2323 Fujitsu FR30 fr30-*-elf*
2324 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2325 Argonaut Risc Chip (ARC) arc-*-*
2326 i386 running Mach 3.0 i[3456]86-*-mach3*
2327 i386 running Mach i[3456]86-*-mach*
2328 i386 running OSF/1 i[3456]86-*osf1mk*
2329 HP/Apollo 68k Family m68*-apollo*-sysv*,
2331 m68*-hp-bsd*, m68*-hp-hpux*
2332 I960 with MON960 i960-*-coff
2334 * OBSOLETE languages
2336 CHILL, a Pascal like language used by telecommunications companies.
2338 * REMOVED configurations and files
2340 AMD 29k family via UDI a29k-amd-udi, udi29k
2341 A29K VxWorks a29k-*-vxworks
2342 AMD 29000 embedded, using EBMON a29k-none-none
2343 AMD 29000 embedded with COFF a29k-none-coff
2344 AMD 29000 embedded with a.out a29k-none-aout
2346 testsuite/gdb.hp/gdb.threads-hp/ directory
2348 * New command "set max-user-call-depth <nnn>"
2350 This command allows the user to limit the call depth of user-defined
2351 commands. The default is 1024.
2353 * Changes in FreeBSD/i386 native debugging.
2355 Support for the "generate-core-file" has been added.
2357 * New commands "dump", "append", and "restore".
2359 These commands allow data to be copied from target memory
2360 to a bfd-format or binary file (dump and append), and back
2361 from a file into memory (restore).
2363 * Improved "next/step" support on multi-processor Alpha Tru64.
2365 The previous single-step mechanism could cause unpredictable problems,
2366 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2367 of a software single-step mechanism prevents this.
2369 *** Changes in GDB 5.2.1:
2377 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2378 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2379 Fix, by Joel Brobecker imported from mainline.
2381 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2382 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2383 Fix, by Fred Fish, imported from mainline.
2385 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2386 Surprisingly enough, it works now.
2387 By Michal Ludvig, imported from mainline.
2389 i386 hardware watchpoint support:
2390 avoid misses on second run for some targets.
2391 By Pierre Muller, imported from mainline.
2393 *** Changes in GDB 5.2:
2395 * New command "set trust-readonly-sections on[off]".
2397 This command is a hint that tells gdb that read-only sections
2398 really are read-only (ie. that their contents will not change).
2399 In this mode, gdb will go to the object file rather than the
2400 target to read memory from read-only sections (such as ".text").
2401 This can be a significant performance improvement on some
2402 (notably embedded) targets.
2404 * New command "generate-core-file" (or "gcore").
2406 This new gdb command allows the user to drop a core file of the child
2407 process state at any time. So far it's been implemented only for
2408 GNU/Linux and Solaris, but should be relatively easily ported to other
2409 hosts. Argument is core file name (defaults to core.<pid>).
2411 * New command line option
2413 GDB now accepts --pid or -p followed by a process id.
2415 * Change in command line behavior -- corefiles vs. process ids.
2417 There is a subtle behavior in the way in which GDB handles
2418 command line arguments. The first non-flag argument is always
2419 a program to debug, but the second non-flag argument may either
2420 be a corefile or a process id. Previously, GDB would attempt to
2421 open the second argument as a corefile, and if that failed, would
2422 issue a superfluous error message and then attempt to attach it as
2423 a process. Now, if the second argument begins with a non-digit,
2424 it will be treated as a corefile. If it begins with a digit,
2425 GDB will attempt to attach it as a process, and if no such process
2426 is found, will then attempt to open it as a corefile.
2428 * Changes in ARM configurations.
2430 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2431 configuration is fully multi-arch.
2433 * New native configurations
2435 ARM NetBSD arm*-*-netbsd*
2436 x86 OpenBSD i[3456]86-*-openbsd*
2437 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2438 Sparc64 running FreeBSD sparc64-*-freebsd*
2442 Sanyo XStormy16 xstormy16-elf
2444 * OBSOLETE configurations and files
2446 Configurations that have been declared obsolete in this release have
2447 been commented out. Unless there is activity to revive these
2448 configurations, the next release of GDB will have their sources
2449 permanently REMOVED.
2451 AMD 29k family via UDI a29k-amd-udi, udi29k
2452 A29K VxWorks a29k-*-vxworks
2453 AMD 29000 embedded, using EBMON a29k-none-none
2454 AMD 29000 embedded with COFF a29k-none-coff
2455 AMD 29000 embedded with a.out a29k-none-aout
2457 testsuite/gdb.hp/gdb.threads-hp/ directory
2459 * REMOVED configurations and files
2461 TI TMS320C80 tic80-*-*
2463 PowerPC Solaris powerpcle-*-solaris*
2464 PowerPC Windows NT powerpcle-*-cygwin32
2465 PowerPC Netware powerpc-*-netware*
2466 Harris/CXUX m88k m88*-harris-cxux*
2467 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2468 ns32k-utek-sysv* ns32k-utek-*
2469 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2470 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2471 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2472 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2473 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2475 * Changes to command line processing
2477 The new `--args' feature can be used to specify command-line arguments
2478 for the inferior from gdb's command line.
2480 * Changes to key bindings
2482 There is a new `operate-and-get-next' function bound to `C-o'.
2484 *** Changes in GDB 5.1.1
2486 Fix compile problem on DJGPP.
2488 Fix a problem with floating-point registers on the i386 being
2491 Fix to stop GDB crashing on .debug_str debug info.
2493 Numerous documentation fixes.
2495 Numerous testsuite fixes.
2497 *** Changes in GDB 5.1:
2499 * New native configurations
2501 Alpha FreeBSD alpha*-*-freebsd*
2502 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2503 MIPS GNU/Linux mips*-*-linux*
2504 MIPS SGI Irix 6.x mips*-sgi-irix6*
2505 ia64 AIX ia64-*-aix*
2506 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2510 Motorola 68HC11 and 68HC12 m68hc11-elf
2512 UltraSparc running GNU/Linux sparc64-*-linux*
2514 * OBSOLETE configurations and files
2516 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2517 Harris/CXUX m88k m88*-harris-cxux*
2518 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2519 ns32k-utek-sysv* ns32k-utek-*
2520 TI TMS320C80 tic80-*-*
2522 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2523 PowerPC Solaris powerpcle-*-solaris*
2524 PowerPC Windows NT powerpcle-*-cygwin32
2525 PowerPC Netware powerpc-*-netware*
2526 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2527 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2528 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2529 Apple Macintosh (MPW) host N/A
2531 stuff.c (Program to stuff files into a specially prepared space in kdb)
2532 kdb-start.c (Main loop for the standalone kernel debugger)
2534 Configurations that have been declared obsolete in this release have
2535 been commented out. Unless there is activity to revive these
2536 configurations, the next release of GDB will have their sources
2537 permanently REMOVED.
2539 * REMOVED configurations and files
2541 Altos 3068 m68*-altos-*
2542 Convex c1-*-*, c2-*-*
2544 ARM RISCix arm-*-* (as host)
2548 * GDB has been converted to ISO C.
2550 GDB's source code has been converted to ISO C. In particular, the
2551 sources are fully protoized, and rely on standard headers being
2556 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2558 * The MI enabled by default.
2560 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2561 revised and enabled by default. Packages which use GDB as a debugging
2562 engine behind a UI or another front end are encouraged to switch to
2563 using the GDB/MI interface, instead of the old annotations interface
2564 which is now deprecated.
2566 * Support for debugging Pascal programs.
2568 GDB now includes support for debugging Pascal programs. The following
2569 main features are supported:
2571 - Pascal-specific data types such as sets;
2573 - automatic recognition of Pascal sources based on file-name
2576 - Pascal-style display of data types, variables, and functions;
2578 - a Pascal expression parser.
2580 However, some important features are not yet supported.
2582 - Pascal string operations are not supported at all;
2584 - there are some problems with boolean types;
2586 - Pascal type hexadecimal constants are not supported
2587 because they conflict with the internal variables format;
2589 - support for Pascal objects and classes is not full yet;
2591 - unlike Pascal, GDB is case-sensitive for symbol names.
2593 * Changes in completion.
2595 Commands such as `shell', `run' and `set args', which pass arguments
2596 to inferior programs, now complete on file names, similar to what
2597 users expect at the shell prompt.
2599 Commands which accept locations, such as `disassemble', `print',
2600 `breakpoint', `until', etc. now complete on filenames as well as
2601 program symbols. Thus, if you type "break foob TAB", and the source
2602 files linked into the programs include `foobar.c', that file name will
2603 be one of the candidates for completion. However, file names are not
2604 considered for completion after you typed a colon that delimits a file
2605 name from a name of a function in that file, as in "break foo.c:bar".
2607 `set demangle-style' completes on available demangling styles.
2609 * New platform-independent commands:
2611 It is now possible to define a post-hook for a command as well as a
2612 hook that runs before the command. For more details, see the
2613 documentation of `hookpost' in the GDB manual.
2615 * Changes in GNU/Linux native debugging.
2617 Support for debugging multi-threaded programs has been completely
2618 revised for all platforms except m68k and sparc. You can now debug as
2619 many threads as your system allows you to have.
2621 Attach/detach is supported for multi-threaded programs.
2623 Support for SSE registers was added for x86. This doesn't work for
2624 multi-threaded programs though.
2626 * Changes in MIPS configurations.
2628 Multi-arch support is enabled for all MIPS configurations.
2630 GDB can now be built as native debugger on SGI Irix 6.x systems for
2631 debugging n32 executables. (Debugging 64-bit executables is not yet
2634 * Unified support for hardware watchpoints in all x86 configurations.
2636 Most (if not all) native x86 configurations support hardware-assisted
2637 breakpoints and watchpoints in a unified manner. This support
2638 implements debug register sharing between watchpoints, which allows to
2639 put a virtually infinite number of watchpoints on the same address,
2640 and also supports watching regions up to 16 bytes with several debug
2643 The new maintenance command `maintenance show-debug-regs' toggles
2644 debugging print-outs in functions that insert, remove, and test
2645 watchpoints and hardware breakpoints.
2647 * Changes in the DJGPP native configuration.
2649 New command ``info dos sysinfo'' displays assorted information about
2650 the CPU, OS, memory, and DPMI server.
2652 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2653 display information about segment descriptors stored in GDT, LDT, and
2656 New commands ``info dos pde'' and ``info dos pte'' display entries
2657 from Page Directory and Page Tables (for now works with CWSDPMI only).
2658 New command ``info dos address-pte'' displays the Page Table entry for
2659 a given linear address.
2661 GDB can now pass command lines longer than 126 characters to the
2662 program being debugged (requires an update to the libdbg.a library
2663 which is part of the DJGPP development kit).
2665 DWARF2 debug info is now supported.
2667 It is now possible to `step' and `next' through calls to `longjmp'.
2669 * Changes in documentation.
2671 All GDB documentation was converted to GFDL, the GNU Free
2672 Documentation License.
2674 Tracepoints-related commands are now fully documented in the GDB
2677 TUI, the Text-mode User Interface, is now documented in the manual.
2679 Tracepoints-related commands are now fully documented in the GDB
2682 The "GDB Internals" manual now has an index. It also includes
2683 documentation of `ui_out' functions, GDB coding standards, x86
2684 hardware watchpoints, and memory region attributes.
2686 * GDB's version number moved to ``version.in''
2688 The Makefile variable VERSION has been replaced by the file
2689 ``version.in''. People creating GDB distributions should update the
2690 contents of this file.
2694 GUD support is now a standard part of the EMACS distribution.
2696 *** Changes in GDB 5.0:
2698 * Improved support for debugging FP programs on x86 targets
2700 Unified and much-improved support for debugging floating-point
2701 programs on all x86 targets. In particular, ``info float'' now
2702 displays the FP registers in the same format on all x86 targets, with
2703 greater level of detail.
2705 * Improvements and bugfixes in hardware-assisted watchpoints
2707 It is now possible to watch array elements, struct members, and
2708 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2709 on x86 targets no longer erroneously trigger when the address is
2712 * Improvements in the native DJGPP version of GDB
2714 The distribution now includes all the scripts and auxiliary files
2715 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2716 machines ``out of the box''.
2718 The DJGPP version can now debug programs that use signals. It is
2719 possible to catch signals that happened in the debuggee, deliver
2720 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2721 would kill the program being debugged.) Programs that hook hardware
2722 interrupts (keyboard, timer, etc.) can also be debugged.
2724 It is now possible to debug DJGPP programs that redirect their
2725 standard handles or switch them to raw (as opposed to cooked) mode, or
2726 even close them. The command ``run < foo > bar'' works as expected,
2727 and ``info terminal'' reports useful information about the debuggee's
2728 terminal, including raw/cooked mode, redirection, etc.
2730 The DJGPP version now uses termios functions for console I/O, which
2731 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2734 DOS-style file names with drive letters are now fully supported by
2737 It is now possible to debug DJGPP programs that switch their working
2738 directory. It is also possible to rerun the debuggee any number of
2739 times without restarting GDB; thus, you can use the same setup,
2740 breakpoints, etc. for many debugging sessions.
2742 * New native configurations
2744 ARM GNU/Linux arm*-*-linux*
2745 PowerPC GNU/Linux powerpc-*-linux*
2749 Motorola MCore mcore-*-*
2750 x86 VxWorks i[3456]86-*-vxworks*
2751 PowerPC VxWorks powerpc-*-vxworks*
2752 TI TMS320C80 tic80-*-*
2754 * OBSOLETE configurations
2756 Altos 3068 m68*-altos-*
2757 Convex c1-*-*, c2-*-*
2759 ARM RISCix arm-*-* (as host)
2762 Configurations that have been declared obsolete will be commented out,
2763 but the code will be left in place. If there is no activity to revive
2764 these configurations before the next release of GDB, the sources will
2765 be permanently REMOVED.
2767 * Gould support removed
2769 Support for the Gould PowerNode and NP1 has been removed.
2771 * New features for SVR4
2773 On SVR4 native platforms (such as Solaris), if you attach to a process
2774 without first loading a symbol file, GDB will now attempt to locate and
2775 load symbols from the running process's executable file.
2777 * Many C++ enhancements
2779 C++ support has been greatly improved. Overload resolution now works properly
2780 in almost all cases. RTTI support is on the way.
2782 * Remote targets can connect to a sub-program
2784 A popen(3) style serial-device has been added. This device starts a
2785 sub-process (such as a stand-alone simulator) and then communicates
2786 with that. The sub-program to run is specified using the syntax
2787 ``|<program> <args>'' vis:
2789 (gdb) set remotedebug 1
2790 (gdb) target extended-remote |mn10300-elf-sim program-args
2792 * MIPS 64 remote protocol
2794 A long standing bug in the mips64 remote protocol where by GDB
2795 expected certain 32 bit registers (ex SR) to be transfered as 32
2796 instead of 64 bits has been fixed.
2798 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2799 added to provide backward compatibility with older versions of GDB.
2801 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2803 The command ``set remotebinarydownload'' command has been replaced by
2804 ``set remote X-packet''. Other commands in ``set remote'' family
2805 include ``set remote P-packet''.
2807 * Breakpoint commands accept ranges.
2809 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2810 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2811 ``tracepoint passcount'' also accepts a range of tracepoints.
2813 * ``apropos'' command added.
2815 The ``apropos'' command searches through command names and
2816 documentation strings, printing out matches, making it much easier to
2817 try to find a command that does what you are looking for.
2821 A new machine oriented interface (MI) has been added to GDB. This
2822 interface is designed for debug environments running GDB as a separate
2823 process. This is part of the long term libGDB project. See the
2824 "GDB/MI" chapter of the GDB manual for further information. It can be
2825 enabled by configuring with:
2827 .../configure --enable-gdbmi
2829 *** Changes in GDB-4.18:
2831 * New native configurations
2833 HP-UX 10.20 hppa*-*-hpux10.20
2834 HP-UX 11.x hppa*-*-hpux11.0*
2835 M68K GNU/Linux m68*-*-linux*
2839 Fujitsu FR30 fr30-*-elf*
2840 Intel StrongARM strongarm-*-*
2841 Mitsubishi D30V d30v-*-*
2843 * OBSOLETE configurations
2845 Gould PowerNode, NP1 np1-*-*, pn-*-*
2847 Configurations that have been declared obsolete will be commented out,
2848 but the code will be left in place. If there is no activity to revive
2849 these configurations before the next release of GDB, the sources will
2850 be permanently REMOVED.
2854 As a compatibility experiment, GDB's source files buildsym.h and
2855 buildsym.c have been converted to pure standard C, no longer
2856 containing any K&R compatibility code. We believe that all systems in
2857 use today either come with a standard C compiler, or have a GCC port
2858 available. If this is not true, please report the affected
2859 configuration to bug-gdb@gnu.org immediately. See the README file for
2860 information about getting a standard C compiler if you don't have one
2865 GDB now uses readline 2.2.
2867 * set extension-language
2869 You can now control the mapping between filename extensions and source
2870 languages by using the `set extension-language' command. For instance,
2871 you can ask GDB to treat .c files as C++ by saying
2872 set extension-language .c c++
2873 The command `info extensions' lists all of the recognized extensions
2874 and their associated languages.
2876 * Setting processor type for PowerPC and RS/6000
2878 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2879 you can use the `set processor' command to specify what variant of the
2880 PowerPC family you are debugging. The command
2884 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2885 following PowerPC and RS6000 variants:
2887 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2888 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2890 403GC IBM PowerPC 403GC
2891 505 Motorola PowerPC 505
2892 860 Motorola PowerPC 860 or 850
2893 601 Motorola PowerPC 601
2894 602 Motorola PowerPC 602
2895 603 Motorola/IBM PowerPC 603 or 603e
2896 604 Motorola PowerPC 604 or 604e
2897 750 Motorola/IBM PowerPC 750 or 750
2899 At the moment, this command just tells GDB what to name the
2900 special-purpose processor registers. Since almost all the affected
2901 registers are inaccessible to user-level programs, this command is
2902 only useful for remote debugging in its present form.
2906 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2907 more extensive support for HP-UX. Added features include shared
2908 library support, kernel threads and hardware watchpoints for 11.00,
2909 support for HP's ANSI C and C++ compilers, and a compatibility mode
2910 for xdb and dbx commands.
2914 HP's donation includes the new concept of catchpoints, which is a
2915 generalization of the old catch command. On HP-UX, it is now possible
2916 to catch exec, fork, and vfork, as well as library loading.
2918 This means that the existing catch command has changed; its first
2919 argument now specifies the type of catch to be set up. See the
2920 output of "help catch" for a list of catchpoint types.
2922 * Debugging across forks
2924 On HP-UX, you can choose which process to debug when a fork() happens
2929 HP has donated a curses-based terminal user interface (TUI). To get
2930 it, build with --enable-tui. Although this can be enabled for any
2931 configuration, at present it only works for native HP debugging.
2933 * GDB remote protocol additions
2935 A new protocol packet 'X' that writes binary data is now available.
2936 Default behavior is to try 'X', then drop back to 'M' if the stub
2937 fails to respond. The settable variable `remotebinarydownload'
2938 allows explicit control over the use of 'X'.
2940 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2941 full 64-bit address. The command
2943 set remoteaddresssize 32
2945 can be used to revert to the old behaviour. For existing remote stubs
2946 the change should not be noticed, as the additional address information
2949 In order to assist in debugging stubs, you may use the maintenance
2950 command `packet' to send any text string to the stub. For instance,
2952 maint packet heythere
2954 sends the packet "$heythere#<checksum>". Note that it is very easy to
2955 disrupt a debugging session by sending the wrong packet at the wrong
2958 The compare-sections command allows you to compare section data on the
2959 target to what is in the executable file without uploading or
2960 downloading, by comparing CRC checksums.
2962 * Tracing can collect general expressions
2964 You may now collect general expressions at tracepoints. This requires
2965 further additions to the target-side stub; see tracepoint.c and
2966 doc/agentexpr.texi for further details.
2968 * mask-address variable for Mips
2970 For Mips targets, you may control the zeroing of the upper 32 bits of
2971 a 64-bit address by entering `set mask-address on'. This is mainly
2972 of interest to users of embedded R4xxx and R5xxx processors.
2974 * Higher serial baud rates
2976 GDB's serial code now allows you to specify baud rates 57600, 115200,
2977 230400, and 460800 baud. (Note that your host system may not be able
2978 to achieve all of these rates.)
2982 The i960 configuration now includes an initial implementation of a
2983 builtin simulator, contributed by Jim Wilson.
2986 *** Changes in GDB-4.17:
2988 * New native configurations
2990 Alpha GNU/Linux alpha*-*-linux*
2991 Unixware 2.x i[3456]86-unixware2*
2992 Irix 6.x mips*-sgi-irix6*
2993 PowerPC GNU/Linux powerpc-*-linux*
2994 PowerPC Solaris powerpcle-*-solaris*
2995 Sparc GNU/Linux sparc-*-linux*
2996 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3000 Argonaut Risc Chip (ARC) arc-*-*
3001 Hitachi H8/300S h8300*-*-*
3002 Matsushita MN10200 w/simulator mn10200-*-*
3003 Matsushita MN10300 w/simulator mn10300-*-*
3004 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3005 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3006 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3007 Mitsubishi D10V w/simulator d10v-*-*
3008 Mitsubishi M32R/D w/simulator m32r-*-elf*
3009 Tsqware Sparclet sparclet-*-*
3010 NEC V850 w/simulator v850-*-*
3012 * New debugging protocols
3014 ARM with RDI protocol arm*-*-*
3015 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3016 DDB and LSI variants of PMON protocol mips*-*-*
3017 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3018 PowerPC with SDS protocol powerpc{,le}-*-eabi
3019 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3023 All configurations can now understand and use the DWARF 2 debugging
3024 format. The choice is automatic, if the symbol file contains DWARF 2
3029 GDB now includes basic Java language support. This support is
3030 only useful with Java compilers that produce native machine code.
3032 * solib-absolute-prefix and solib-search-path
3034 For SunOS and SVR4 shared libraries, you may now set the prefix for
3035 loading absolute shared library symbol files, and the search path for
3036 locating non-absolute shared library symbol files.
3038 * Live range splitting
3040 GDB can now effectively debug code for which GCC has performed live
3041 range splitting as part of its optimization. See gdb/doc/LRS for
3042 more details on the expected format of the stabs information.
3046 GDB's support for the GNU Hurd, including thread debugging, has been
3047 updated to work with current versions of the Hurd.
3051 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3052 instruction set. ARM GDB automatically detects when Thumb
3053 instructions are in use, and adjusts disassembly and backtracing
3058 GDB's MIPS target configurations now handle the MIP16 16-bit
3063 GDB now includes support for overlays; if an executable has been
3064 linked such that multiple sections are based at the same address, GDB
3065 will decide which section to use for symbolic info. You can choose to
3066 control the decision manually, using overlay commands, or implement
3067 additional target-side support and use "overlay load-target" to bring
3068 in the overlay mapping. Do "help overlay" for more detail.
3072 The command "info symbol <address>" displays information about
3073 the symbol at the specified address.
3077 The standard remote protocol now includes an extension that allows
3078 asynchronous collection and display of trace data. This requires
3079 extensive support in the target-side debugging stub. Tracing mode
3080 includes a new interaction mode in GDB and new commands: see the
3081 file tracepoint.c for more details.
3085 Configurations for embedded MIPS now include a simulator contributed
3086 by Cygnus Solutions. The simulator supports the instruction sets
3087 of most MIPS variants.
3091 Sparc configurations may now include the ERC32 simulator contributed
3092 by the European Space Agency. The simulator is not built into
3093 Sparc targets by default; configure with --enable-sim to include it.
3097 For target configurations that may include multiple variants of a
3098 basic architecture (such as MIPS and SH), you may now set the
3099 architecture explicitly. "set arch" sets, "info arch" lists
3100 the possible architectures.
3102 *** Changes in GDB-4.16:
3104 * New native configurations
3106 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3107 M68K NetBSD m68k-*-netbsd*
3108 PowerPC AIX 4.x powerpc-*-aix*
3109 PowerPC MacOS powerpc-*-macos*
3110 PowerPC Windows NT powerpcle-*-cygwin32
3111 RS/6000 AIX 4.x rs6000-*-aix4*
3115 ARM with RDP protocol arm-*-*
3116 I960 with MON960 i960-*-coff
3117 MIPS VxWorks mips*-*-vxworks*
3118 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3119 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3121 Matra Sparclet sparclet-*-*
3125 The powerpc-eabi configuration now includes the PSIM simulator,
3126 contributed by Andrew Cagney, with assistance from Mike Meissner.
3127 PSIM is a very elaborate model of the PowerPC, including not only
3128 basic instruction set execution, but also details of execution unit
3129 performance and I/O hardware. See sim/ppc/README for more details.
3133 GDB now works with Solaris 2.5.
3135 * Windows 95/NT native
3137 GDB will now work as a native debugger on Windows 95 and Windows NT.
3138 To build it from source, you must use the "gnu-win32" environment,
3139 which uses a DLL to emulate enough of Unix to run the GNU tools.
3140 Further information, binaries, and sources are available at
3141 ftp.cygnus.com, under pub/gnu-win32.
3143 * dont-repeat command
3145 If a user-defined command includes the command `dont-repeat', then the
3146 command will not be repeated if the user just types return. This is
3147 useful if the command is time-consuming to run, so that accidental
3148 extra keystrokes don't run the same command many times.
3150 * Send break instead of ^C
3152 The standard remote protocol now includes an option to send a break
3153 rather than a ^C to the target in order to interrupt it. By default,
3154 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3156 * Remote protocol timeout
3158 The standard remote protocol includes a new variable `remotetimeout'
3159 that allows you to set the number of seconds before GDB gives up trying
3160 to read from the target. The default value is 2.
3162 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3164 By default GDB will automatically keep track of objects as they are
3165 loaded and unloaded by the dynamic linker. By using the command `set
3166 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3167 when shared library events occur, thus allowing you to set breakpoints
3168 in shared libraries which are explicitly loaded by the inferior.
3170 Note this feature does not work on hpux8. On hpux9 you must link
3171 /usr/lib/end.o into your program. This feature should work
3172 automatically on hpux10.
3174 * Irix 5.x hardware watchpoint support
3176 Irix 5 configurations now support the use of hardware watchpoints.
3178 * Mips protocol "SYN garbage limit"
3180 When debugging a Mips target using the `target mips' protocol, you
3181 may set the number of characters that GDB will ignore by setting
3182 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3183 every character. The default value is 1050.
3185 * Recording and replaying remote debug sessions
3187 If you set `remotelogfile' to the name of a file, gdb will write to it
3188 a recording of a remote debug session. This recording may then be
3189 replayed back to gdb using "gdbreplay". See gdbserver/README for
3190 details. This is useful when you have a problem with GDB while doing
3191 remote debugging; you can make a recording of the session and send it
3192 to someone else, who can then recreate the problem.
3194 * Speedups for remote debugging
3196 GDB includes speedups for downloading and stepping MIPS systems using
3197 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3198 and more efficient S-record downloading.
3200 * Memory use reductions and statistics collection
3202 GDB now uses less memory and reports statistics about memory usage.
3203 Try the `maint print statistics' command, for example.
3205 *** Changes in GDB-4.15:
3207 * Psymtabs for XCOFF
3209 The symbol reader for AIX GDB now uses partial symbol tables. This
3210 can greatly improve startup time, especially for large executables.
3212 * Remote targets use caching
3214 Remote targets now use a data cache to speed up communication with the
3215 remote side. The data cache could lead to incorrect results because
3216 it doesn't know about volatile variables, thus making it impossible to
3217 debug targets which use memory mapped I/O devices. `set remotecache
3218 off' turns the the data cache off.
3220 * Remote targets may have threads
3222 The standard remote protocol now includes support for multiple threads
3223 in the target system, using new protocol commands 'H' and 'T'. See
3224 gdb/remote.c for details.
3228 If GDB is configured with `--enable-netrom', then it will include
3229 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3230 acts as though it is a bank of ROM on the target board, but you can
3231 write into it over the network. GDB's support consists only of
3232 support for fast loading into the emulated ROM; to debug, you must use
3233 another protocol, such as standard remote protocol. The usual
3234 sequence is something like
3236 target nrom <netrom-hostname>
3238 target remote <netrom-hostname>:1235
3242 GDB now includes support for the Apple Macintosh, as a host only. It
3243 may be run as either an MPW tool or as a standalone application, and
3244 it can debug through the serial port. All the usual GDB commands are
3245 available, but to the target command, you must supply "serial" as the
3246 device type instead of "/dev/ttyXX". See mpw-README in the main
3247 directory for more information on how to build. The MPW configuration
3248 scripts */mpw-config.in support only a few targets, and only the
3249 mips-idt-ecoff target has been tested.
3253 GDB configuration now uses autoconf. This is not user-visible,
3254 but does simplify configuration and building.
3258 GDB now supports hpux10.
3260 *** Changes in GDB-4.14:
3262 * New native configurations
3264 x86 FreeBSD i[345]86-*-freebsd
3265 x86 NetBSD i[345]86-*-netbsd
3266 NS32k NetBSD ns32k-*-netbsd
3267 Sparc NetBSD sparc-*-netbsd
3271 A29K VxWorks a29k-*-vxworks
3272 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3273 CPU32 EST-300 emulator m68*-*-est*
3274 PowerPC ELF powerpc-*-elf
3277 * Alpha OSF/1 support for procfs
3279 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3280 possible to attach to running processes. As the mounting of the /proc
3281 filesystem is optional on the Alpha, GDB automatically determines
3282 the availability of /proc during startup. This can lead to problems
3283 if /proc is unmounted after GDB has been started.
3285 * Arguments to user-defined commands
3287 User commands may accept up to 10 arguments separated by whitespace.
3288 Arguments are accessed within the user command via $arg0..$arg9. A
3291 print $arg0 + $arg1 + $arg2
3293 To execute the command use:
3296 Defines the command "adder" which prints the sum of its three arguments.
3297 Note the arguments are text substitutions, so they may reference variables,
3298 use complex expressions, or even perform inferior function calls.
3300 * New `if' and `while' commands
3302 This makes it possible to write more sophisticated user-defined
3303 commands. Both commands take a single argument, which is the
3304 expression to evaluate, and must be followed by the commands to
3305 execute, one per line, if the expression is nonzero, the list being
3306 terminated by the word `end'. The `if' command list may include an
3307 `else' word, which causes the following commands to be executed only
3308 if the expression is zero.
3310 * Fortran source language mode
3312 GDB now includes partial support for Fortran 77. It will recognize
3313 Fortran programs and can evaluate a subset of Fortran expressions, but
3314 variables and functions may not be handled correctly. GDB will work
3315 with G77, but does not yet know much about symbols emitted by other
3318 * Better HPUX support
3320 Most debugging facilities now work on dynamic executables for HPPAs
3321 running hpux9 or later. You can attach to running dynamically linked
3322 processes, but by default the dynamic libraries will be read-only, so
3323 for instance you won't be able to put breakpoints in them. To change
3324 that behavior do the following before running the program:
3330 This will cause the libraries to be mapped private and read-write.
3331 To revert to the normal behavior, do this:
3337 You cannot set breakpoints or examine data in the library until after
3338 the library is loaded if the function/data symbols do not have
3341 GDB can now also read debug symbols produced by the HP C compiler on
3342 HPPAs (sorry, no C++, Fortran or 68k support).
3344 * Target byte order now dynamically selectable
3346 You can choose which byte order to use with a target system, via the
3347 commands "set endian big" and "set endian little", and you can see the
3348 current setting by using "show endian". You can also give the command
3349 "set endian auto", in which case GDB will use the byte order
3350 associated with the executable. Currently, only embedded MIPS
3351 configurations support dynamic selection of target byte order.
3353 * New DOS host serial code
3355 This version uses DPMI interrupts to handle buffered I/O, so you
3356 no longer need to run asynctsr when debugging boards connected to
3359 *** Changes in GDB-4.13:
3361 * New "complete" command
3363 This lists all the possible completions for the rest of the line, if it
3364 were to be given as a command itself. This is intended for use by emacs.
3366 * Trailing space optional in prompt
3368 "set prompt" no longer adds a space for you after the prompt you set. This
3369 allows you to set a prompt which ends in a space or one that does not.
3371 * Breakpoint hit counts
3373 "info break" now displays a count of the number of times the breakpoint
3374 has been hit. This is especially useful in conjunction with "ignore"; you
3375 can ignore a large number of breakpoint hits, look at the breakpoint info
3376 to see how many times the breakpoint was hit, then run again, ignoring one
3377 less than that number, and this will get you quickly to the last hit of
3380 * Ability to stop printing at NULL character
3382 "set print null-stop" will cause GDB to stop printing the characters of
3383 an array when the first NULL is encountered. This is useful when large
3384 arrays actually contain only short strings.
3386 * Shared library breakpoints
3388 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3389 breakpoints in shared libraries before the executable is run.
3391 * Hardware watchpoints
3393 There is a new hardware breakpoint for the watch command for sparclite
3394 targets. See gdb/sparclite/hw_breakpoint.note.
3396 Hardware watchpoints are also now supported under GNU/Linux.
3400 Annotations have been added. These are for use with graphical interfaces,
3401 and are still experimental. Currently only gdba.el uses these.
3403 * Improved Irix 5 support
3405 GDB now works properly with Irix 5.2.
3407 * Improved HPPA support
3409 GDB now works properly with the latest GCC and GAS.
3411 * New native configurations
3413 Sequent PTX4 i[34]86-sequent-ptx4
3414 HPPA running OSF/1 hppa*-*-osf*
3415 Atari TT running SVR4 m68*-*-sysv4*
3416 RS/6000 LynxOS rs6000-*-lynxos*
3420 OS/9000 i[34]86-*-os9k
3421 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3424 * Hitachi SH7000 and E7000-PC ICE support
3426 There is now support for communicating with the Hitachi E7000-PC ICE.
3427 This is available automatically when GDB is configured for the SH.
3431 As usual, a variety of small fixes and improvements, both generic
3432 and configuration-specific. See the ChangeLog for more detail.
3434 *** Changes in GDB-4.12:
3436 * Irix 5 is now supported
3440 GDB-4.12 on the HPPA has a number of changes which make it unable
3441 to debug the output from the currently released versions of GCC and
3442 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3443 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3444 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3447 *** Changes in GDB-4.11:
3449 * User visible changes:
3453 The "set remotedebug" option is now consistent between the mips remote
3454 target, remote targets using the gdb-specific protocol, UDI (AMD's
3455 debug protocol for the 29k) and the 88k bug monitor. It is now an
3456 integer specifying a debug level (normally 0 or 1, but 2 means more
3457 debugging info for the mips target).
3459 * DEC Alpha native support
3461 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3462 debug info, but GDB works fairly well with the DEC compiler and should
3463 work with a future GCC release. See the README file for a few
3464 Alpha-specific notes.
3466 * Preliminary thread implementation
3468 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3470 * LynxOS native and target support for 386
3472 This release has been hosted on LynxOS 2.2, and also can be configured
3473 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3476 * Improvements in C++ mangling/demangling.
3478 This release has much better g++ debugging, specifically in name
3479 mangling/demangling, virtual function calls, print virtual table,
3480 call methods, ...etc.
3482 *** Changes in GDB-4.10:
3484 * User visible changes:
3486 Remote debugging using the GDB-specific (`target remote') protocol now
3487 supports the `load' command. This is only useful if you have some
3488 other way of getting the stub to the target system, and you can put it
3489 somewhere in memory where it won't get clobbered by the download.
3491 Filename completion now works.
3493 When run under emacs mode, the "info line" command now causes the
3494 arrow to point to the line specified. Also, "info line" prints
3495 addresses in symbolic form (as well as hex).
3497 All vxworks based targets now support a user settable option, called
3498 vxworks-timeout. This option represents the number of seconds gdb
3499 should wait for responses to rpc's. You might want to use this if
3500 your vxworks target is, perhaps, a slow software simulator or happens
3501 to be on the far side of a thin network line.
3505 This release contains support for using a DEC alpha as a GDB host for
3506 cross debugging. Native alpha debugging is not supported yet.
3509 *** Changes in GDB-4.9:
3513 This is the first GDB release which is accompanied by a matching testsuite.
3514 The testsuite requires installation of dejagnu, which should be available
3515 via ftp from most sites that carry GNU software.
3519 'Cfront' style demangling has had its name changed to 'ARM' style, to
3520 emphasize that it was written from the specifications in the C++ Annotated
3521 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3522 disclaimers, it still generated too much confusion with users attempting to
3523 use gdb with AT&T cfront.
3527 GDB now uses a standard remote interface to a simulator library.
3528 So far, the library contains simulators for the Zilog Z8001/2, the
3529 Hitachi H8/300, H8/500 and Super-H.
3531 * New targets supported
3533 H8/300 simulator h8300-hitachi-hms or h8300hms
3534 H8/500 simulator h8500-hitachi-hms or h8500hms
3535 SH simulator sh-hitachi-hms or sh
3536 Z8000 simulator z8k-zilog-none or z8ksim
3537 IDT MIPS board over serial line mips-idt-ecoff
3539 Cross-debugging to GO32 targets is supported. It requires a custom
3540 version of the i386-stub.c module which is integrated with the
3541 GO32 memory extender.
3543 * New remote protocols
3545 MIPS remote debugging protocol.
3547 * New source languages supported
3549 This version includes preliminary support for Chill, a Pascal like language
3550 used by telecommunications companies. Chill support is also being integrated
3551 into the GNU compiler, but we don't know when it will be publically available.
3554 *** Changes in GDB-4.8:
3556 * HP Precision Architecture supported
3558 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3559 version of this support was available as a set of patches from the
3560 University of Utah. GDB does not support debugging of programs
3561 compiled with the HP compiler, because HP will not document their file
3562 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3563 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3565 Many problems in the preliminary version have been fixed.
3567 * Faster and better demangling
3569 We have improved template demangling and fixed numerous bugs in the GNU style
3570 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3571 character types (wchar_t) are now supported. Demangling of each symbol is now
3572 only done once, and is cached when the symbol table for a file is read in.
3573 This results in a small increase in memory usage for C programs, a moderate
3574 increase in memory usage for C++ programs, and a fantastic speedup in
3577 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3578 from the specifications in the Annotated Reference Manual, which AT&T's
3579 compiler does not actually implement.
3581 * G++ multiple inheritance compiler problem
3583 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3584 inheritance lattices was reworked to properly discover ambiguities. We
3585 recently found an example which causes this new algorithm to fail in a
3586 very subtle way, producing bad debug information for those classes.
3587 The file 'gcc.patch' (in this directory) can be applied to gcc to
3588 circumvent the problem. A future GCC release will contain a complete
3591 The previous G++ debug info problem (mentioned below for the gdb-4.7
3592 release) is fixed in gcc version 2.3.2.
3594 * Improved configure script
3596 The `configure' script will now attempt to guess your system type if
3597 you don't supply a host system type. The old scheme of supplying a
3598 host system triplet is preferable over using this. All the magic is
3599 done in the new `config.guess' script. Examine it for details.
3601 We have also brought our configure script much more in line with the FSF's
3602 version. It now supports the --with-xxx options. In particular,
3603 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3604 The resulting GDB will not be able to read arbitrary object file formats --
3605 only the format ``expected'' to be used on the configured target system.
3606 We hope to make this the default in a future release.
3608 * Documentation improvements
3610 There's new internal documentation on how to modify GDB, and how to
3611 produce clean changes to the code. We implore people to read it
3612 before submitting changes.
3614 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3615 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3616 `info' files are also provided. To build `info' files from scratch,
3617 you will need the latest `makeinfo' release, which will be available in
3618 a future texinfo-X.Y release.
3620 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3621 We're not sure exactly which versions have this problem, but it has
3622 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3623 or better. If that isn't possible, there is a patch in
3624 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3625 around this problem.
3629 GDB now supports array constants that can be used in expressions typed in by
3630 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3631 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3634 The new directory `gdb/sparclite' contains a program that demonstrates
3635 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3637 * New native hosts supported
3639 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3640 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3642 * New targets supported
3644 AMD 29k family via UDI a29k-amd-udi or udi29k
3646 * New file formats supported
3648 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3649 HPUX core files, and SCO 3.2v2 core files.
3653 Attaching to processes now works again; thanks for the many bug reports.
3655 We have also stomped on a bunch of core dumps caused by
3656 printf_filtered("%s") problems.
3658 We eliminated a copyright problem on the rpc and ptrace header files
3659 for VxWorks, which was discovered at the last minute during the 4.7
3660 release. You should now be able to build a VxWorks GDB.
3662 You can now interrupt gdb while an attached process is running. This
3663 will cause the attached process to stop, and give control back to GDB.
3665 We fixed problems caused by using too many file descriptors
3666 for reading symbols from object files and libraries. This was
3667 especially a problem for programs that used many (~100) shared
3670 The `step' command now only enters a subroutine if there is line number
3671 information for the subroutine. Otherwise it acts like the `next'
3672 command. Previously, `step' would enter subroutines if there was
3673 any debugging information about the routine. This avoids problems
3674 when using `cc -g1' on MIPS machines.
3676 * Internal improvements
3678 GDB's internal interfaces have been improved to make it easier to support
3679 debugging of multiple languages in the future.
3681 GDB now uses a common structure for symbol information internally.
3682 Minimal symbols (derived from linkage symbols in object files), partial
3683 symbols (from a quick scan of debug information), and full symbols
3684 contain a common subset of information, making it easier to write
3685 shared code that handles any of them.
3687 * New command line options
3689 We now accept --silent as an alias for --quiet.
3693 The memory-mapped-malloc library is now licensed under the GNU Library
3694 General Public License.
3696 *** Changes in GDB-4.7:
3698 * Host/native/target split
3700 GDB has had some major internal surgery to untangle the support for
3701 hosts and remote targets. Now, when you configure GDB for a remote
3702 target, it will no longer load in all of the support for debugging
3703 local programs on the host. When fully completed and tested, this will
3704 ensure that arbitrary host/target combinations are possible.
3706 The primary conceptual shift is to separate the non-portable code in
3707 GDB into three categories. Host specific code is required any time GDB
3708 is compiled on that host, regardless of the target. Target specific
3709 code relates to the peculiarities of the target, but can be compiled on
3710 any host. Native specific code is everything else: it can only be
3711 built when the host and target are the same system. Child process
3712 handling and core file support are two common `native' examples.
3714 GDB's use of /proc for controlling Unix child processes is now cleaner.
3715 It has been split out into a single module under the `target_ops' vector,
3716 plus two native-dependent functions for each system that uses /proc.
3718 * New hosts supported
3720 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3721 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3722 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3724 * New targets supported
3726 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3727 68030 and CPU32 m68030-*-*, m68332-*-*
3729 * New native hosts supported
3731 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3732 (386bsd is not well tested yet)
3733 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3735 * New file formats supported
3737 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3738 supports reading of `a.out.adobe' object files, which are an a.out
3739 format extended with minimal information about multiple sections.
3743 `show copying' is the same as the old `info copying'.
3744 `show warranty' is the same as `info warrantee'.
3745 These were renamed for consistency. The old commands continue to work.
3747 `info handle' is a new alias for `info signals'.
3749 You can now define pre-command hooks, which attach arbitrary command
3750 scripts to any command. The commands in the hook will be executed
3751 prior to the user's command. You can also create a hook which will be
3752 executed whenever the program stops. See gdb.texinfo.
3756 We now deal with Cfront style name mangling, and can even extract type
3757 info from mangled symbols. GDB can automatically figure out which
3758 symbol mangling style your C++ compiler uses.
3760 Calling of methods and virtual functions has been improved as well.
3764 The crash that occured when debugging Sun Ansi-C compiled binaries is
3765 fixed. This was due to mishandling of the extra N_SO stabs output
3768 We also finally got Ultrix 4.2 running in house, and fixed core file
3769 support, with help from a dozen people on the net.
3771 John M. Farrell discovered that the reason that single-stepping was so
3772 slow on all of the Mips based platforms (primarily SGI and DEC) was
3773 that we were trying to demangle and lookup a symbol used for internal
3774 purposes on every instruction that was being stepped through. Changing
3775 the name of that symbol so that it couldn't be mistaken for a C++
3776 mangled symbol sped things up a great deal.
3778 Rich Pixley sped up symbol lookups in general by getting much smarter
3779 about when C++ symbol mangling is necessary. This should make symbol
3780 completion (TAB on the command line) much faster. It's not as fast as
3781 we'd like, but it's significantly faster than gdb-4.6.
3785 A new user controllable variable 'call_scratch_address' can
3786 specify the location of a scratch area to be used when GDB
3787 calls a function in the target. This is necessary because the
3788 usual method of putting the scratch area on the stack does not work
3789 in systems that have separate instruction and data spaces.
3791 We integrated changes to support the 29k UDI (Universal Debugger
3792 Interface), but discovered at the last minute that we didn't have all
3793 of the appropriate copyright paperwork. We are working with AMD to
3794 resolve this, and hope to have it available soon.
3798 We have sped up the remote serial line protocol, especially for targets
3799 with lots of registers. It now supports a new `expedited status' ('T')
3800 message which can be used in place of the existing 'S' status message.
3801 This allows the remote stub to send only the registers that GDB
3802 needs to make a quick decision about single-stepping or conditional
3803 breakpoints, eliminating the need to fetch the entire register set for
3804 each instruction being stepped through.
3806 The GDB remote serial protocol now implements a write-through cache for
3807 registers, only re-reading the registers if the target has run.
3809 There is also a new remote serial stub for SPARC processors. You can
3810 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3811 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3812 processor with a serial port.
3816 Configure.in files have become much easier to read and modify. A new
3817 `table driven' format makes it more obvious what configurations are
3818 supported, and what files each one uses.
3822 There is a new opcodes library which will eventually contain all of the
3823 disassembly routines and opcode tables. At present, it only contains
3824 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3825 disassembler (binutils/objdump) to share these routines.
3827 The libiberty library is now copylefted under the GNU Library General
3828 Public License. This allows more liberal use, and was done so libg++
3829 can use it. This makes no difference to GDB, since the Library License
3830 grants all the rights from the General Public License.
3834 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3835 reference to the stabs symbol info used by the debugger. It is (as far
3836 as we know) the only published document on this fascinating topic. We
3837 encourage you to read it, compare it to the stabs information on your
3838 system, and send improvements on the document in general (to
3839 bug-gdb@prep.ai.mit.edu).
3841 And, of course, many bugs have been fixed.
3844 *** Changes in GDB-4.6:
3846 * Better support for C++ function names
3848 GDB now accepts as input the "demangled form" of C++ overloaded function
3849 names and member function names, and can do command completion on such names
3850 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3851 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3852 Make use of command completion, it is your friend.
3854 GDB also now accepts a variety of C++ mangled symbol formats. They are
3855 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3856 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3857 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3858 for the list of formats.
3860 * G++ symbol mangling problem
3862 Recent versions of gcc have a bug in how they emit debugging information for
3863 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3864 directory) can be applied to gcc to fix the problem. Alternatively, if you
3865 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3866 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3867 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3870 * New 'maintenance' command
3872 All of the commands related to hacking GDB internals have been moved out of
3873 the main command set, and now live behind the 'maintenance' command. This
3874 can also be abbreviated as 'mt'. The following changes were made:
3876 dump-me -> maintenance dump-me
3877 info all-breakpoints -> maintenance info breakpoints
3878 printmsyms -> maintenance print msyms
3879 printobjfiles -> maintenance print objfiles
3880 printpsyms -> maintenance print psymbols
3881 printsyms -> maintenance print symbols
3883 The following commands are new:
3885 maintenance demangle Call internal GDB demangler routine to
3886 demangle a C++ link name and prints the result.
3887 maintenance print type Print a type chain for a given symbol
3889 * Change to .gdbinit file processing
3891 We now read the $HOME/.gdbinit file before processing the argv arguments
3892 (e.g. reading symbol files or core files). This allows global parameters to
3893 be set, which will apply during the symbol reading. The ./.gdbinit is still
3894 read after argv processing.
3896 * New hosts supported
3898 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3900 GNU/Linux support i386-unknown-linux or linux
3902 We are also including code to support the HP/PA running BSD and HPUX. This
3903 is almost guaranteed not to work, as we didn't have time to test or build it
3904 for this release. We are including it so that the more adventurous (or
3905 masochistic) of you can play with it. We also had major problems with the
3906 fact that the compiler that we got from HP doesn't support the -g option.
3909 * New targets supported
3911 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3913 * More smarts about finding #include files
3915 GDB now remembers the compilation directory for all include files, and for
3916 all files from which C is generated (like yacc and lex sources). This
3917 greatly improves GDB's ability to find yacc/lex sources, and include files,
3918 especially if you are debugging your program from a directory different from
3919 the one that contains your sources.
3921 We also fixed a bug which caused difficulty with listing and setting
3922 breakpoints in include files which contain C code. (In the past, you had to
3923 try twice in order to list an include file that you hadn't looked at before.)
3925 * Interesting infernals change
3927 GDB now deals with arbitrary numbers of sections, where the symbols for each
3928 section must be relocated relative to that section's landing place in the
3929 target's address space. This work was needed to support ELF with embedded
3930 stabs used by Solaris-2.0.
3932 * Bug fixes (of course!)
3934 There have been loads of fixes for the following things:
3935 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3936 i960, stabs, DOS(GO32), procfs, etc...
3938 See the ChangeLog for details.
3940 *** Changes in GDB-4.5:
3942 * New machines supported (host and target)
3944 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3946 SGI Irix-4.x mips-sgi-irix4 or iris4
3948 * New malloc package
3950 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3951 Mmalloc is capable of handling mutiple heaps of memory. It is also
3952 capable of saving a heap to a file, and then mapping it back in later.
3953 This can be used to greatly speedup the startup of GDB by using a
3954 pre-parsed symbol table which lives in a mmalloc managed heap. For
3955 more details, please read mmalloc/mmalloc.texi.
3959 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3960 'help info proc' for details.
3962 * MIPS ecoff symbol table format
3964 The code that reads MIPS symbol table format is now supported on all hosts.
3965 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3968 * File name changes for MS-DOS
3970 Many files in the config directories have been renamed to make it easier to
3971 support GDB on MS-DOSe systems (which have very restrictive file name
3972 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3973 environment) is close to working but has some remaining problems. Note
3974 that debugging of DOS programs is not supported, due to limitations
3975 in the ``operating system'', but it can be used to host cross-debugging.
3977 * Cross byte order fixes
3979 Many fixes have been made to support cross debugging of Sparc and MIPS
3980 targets from hosts whose byte order differs.
3982 * New -mapped and -readnow options
3984 If memory-mapped files are available on your system through the 'mmap'
3985 system call, you can use the -mapped option on the `file' or
3986 `symbol-file' commands to cause GDB to write the symbols from your
3987 program into a reusable file. If the program you are debugging is
3988 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3989 Future GDB debugging sessions will notice the presence of this file,
3990 and will quickly map in symbol information from it, rather than reading
3991 the symbol table from the executable program. Using the '-mapped'
3992 option in a GDB `file' or `symbol-file' command has the same effect as
3993 starting GDB with the '-mapped' command-line option.
3995 You can cause GDB to read the entire symbol table immediately by using
3996 the '-readnow' option with any of the commands that load symbol table
3997 information (or on the GDB command line). This makes the command
3998 slower, but makes future operations faster.
4000 The -mapped and -readnow options are typically combined in order to
4001 build a `fred.syms' file that contains complete symbol information.
4002 A simple GDB invocation to do nothing but build a `.syms' file for future
4005 gdb -batch -nx -mapped -readnow programname
4007 The `.syms' file is specific to the host machine on which GDB is run.
4008 It holds an exact image of GDB's internal symbol table. It cannot be
4009 shared across multiple host platforms.
4011 * longjmp() handling
4013 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4014 siglongjmp() without losing control. This feature has not yet been ported to
4015 all systems. It currently works on many 386 platforms, all MIPS-based
4016 platforms (SGI, DECstation, etc), and Sun3/4.
4020 Preliminary work has been put in to support the new Solaris OS from Sun. At
4021 this time, it can control and debug processes, but it is not capable of
4026 As always, many many bug fixes. The major areas were with g++, and mipsread.
4027 People using the MIPS-based platforms should experience fewer mysterious
4028 crashes and trashed symbol tables.
4030 *** Changes in GDB-4.4:
4032 * New machines supported (host and target)
4034 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4036 BSD Reno on Vax vax-dec-bsd
4037 Ultrix on Vax vax-dec-ultrix
4039 * New machines supported (target)
4041 AMD 29000 embedded, using EBMON a29k-none-none
4045 GDB continues to improve its handling of C++. `References' work better.
4046 The demangler has also been improved, and now deals with symbols mangled as
4047 per the Annotated C++ Reference Guide.
4049 GDB also now handles `stabs' symbol information embedded in MIPS
4050 `ecoff' symbol tables. Since the ecoff format was not easily
4051 extensible to handle new languages such as C++, this appeared to be a
4052 good way to put C++ debugging info into MIPS binaries. This option
4053 will be supported in the GNU C compiler, version 2, when it is
4056 * New features for SVR4
4058 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4059 shared libraries. Debugging dynamically linked programs should present
4060 only minor differences from debugging statically linked programs.
4062 The `info proc' command will print out information about any process
4063 on an SVR4 system (including the one you are debugging). At the moment,
4064 it prints the address mappings of the process.
4066 If you bring up GDB on another SVR4 system, please send mail to
4067 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4069 * Better dynamic linking support in SunOS
4071 Reading symbols from shared libraries which contain debugging symbols
4072 now works properly. However, there remain issues such as automatic
4073 skipping of `transfer vector' code during function calls, which
4074 make it harder to debug code in a shared library, than to debug the
4075 same code linked statically.
4079 GDB is now using the latest `getopt' routines from the FSF. This
4080 version accepts the -- prefix for options with long names. GDB will
4081 continue to accept the old forms (-option and +option) as well.
4082 Various single letter abbreviations for options have been explicity
4083 added to the option table so that they won't get overshadowed in the
4084 future by other options that begin with the same letter.
4088 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4089 Many assorted bugs have been handled. Many more remain to be handled.
4090 See the various ChangeLog files (primarily in gdb and bfd) for details.
4093 *** Changes in GDB-4.3:
4095 * New machines supported (host and target)
4097 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4098 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4099 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4101 * Almost SCO Unix support
4103 We had hoped to support:
4104 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4105 (except for core file support), but we discovered very late in the release
4106 that it has problems with process groups that render gdb unusable. Sorry
4107 about that. I encourage people to fix it and post the fixes.
4109 * Preliminary ELF and DWARF support
4111 GDB can read ELF object files on System V Release 4, and can handle
4112 debugging records for C, in DWARF format, in ELF files. This support
4113 is preliminary. If you bring up GDB on another SVR4 system, please
4114 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4119 GDB now uses the latest `readline' library. One user-visible change
4120 is that two tabs will list possible command completions, which previously
4121 required typing M-? (meta-question mark, or ESC ?).
4125 The `stepi' bug that many of you noticed has been squashed.
4126 Many bugs in C++ have been handled. Many more remain to be handled.
4127 See the various ChangeLog files (primarily in gdb and bfd) for details.
4129 * State of the MIPS world (in case you wondered):
4131 GDB can understand the symbol tables emitted by the compilers
4132 supplied by most vendors of MIPS-based machines, including DEC. These
4133 symbol tables are in a format that essentially nobody else uses.
4135 Some versions of gcc come with an assembler post-processor called
4136 mips-tfile. This program is required if you want to do source-level
4137 debugging of gcc-compiled programs. I believe FSF does not ship
4138 mips-tfile with gcc version 1, but it will eventually come with gcc
4141 Debugging of g++ output remains a problem. g++ version 1.xx does not
4142 really support it at all. (If you're lucky, you should be able to get
4143 line numbers and stack traces to work, but no parameters or local
4144 variables.) With some work it should be possible to improve the
4147 When gcc version 2 is released, you will have somewhat better luck.
4148 However, even then you will get confusing results for inheritance and
4151 We will eventually provide full debugging of g++ output on
4152 DECstations. This will probably involve some kind of stabs-in-ecoff
4153 encapulation, but the details have not been worked out yet.
4156 *** Changes in GDB-4.2:
4158 * Improved configuration
4160 Only one copy of `configure' exists now, and it is not self-modifying.
4161 Porting BFD is simpler.
4165 The `step' and `next' commands now only stop at the first instruction
4166 of a source line. This prevents the multiple stops that used to occur
4167 in switch statements, for-loops, etc. `Step' continues to stop if a
4168 function that has debugging information is called within the line.
4172 Lots of small bugs fixed. More remain.
4174 * New host supported (not target)
4176 Intel 386 PC clone running Mach i386-none-mach
4179 *** Changes in GDB-4.1:
4181 * Multiple source language support
4183 GDB now has internal scaffolding to handle several source languages.
4184 It determines the type of each source file from its filename extension,
4185 and will switch expression parsing and number formatting to match the
4186 language of the function in the currently selected stack frame.
4187 You can also specifically set the language to be used, with
4188 `set language c' or `set language modula-2'.
4192 GDB now has preliminary support for the GNU Modula-2 compiler,
4193 currently under development at the State University of New York at
4194 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4195 continue through the fall of 1991 and into 1992.
4197 Other Modula-2 compilers are currently not supported, and attempting to
4198 debug programs compiled with them will likely result in an error as the
4199 symbol table is read. Feel free to work on it, though!
4201 There are hooks in GDB for strict type checking and range checking,
4202 in the `Modula-2 philosophy', but they do not currently work.
4206 GDB can now write to executable and core files (e.g. patch
4207 a variable's value). You must turn this switch on, specify
4208 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4209 by assigning a new value to a variable. Modifications take
4212 * Automatic SunOS shared library reading
4214 When you run your program, GDB automatically determines where its
4215 shared libraries (if any) have been loaded, and reads their symbols.
4216 The `share' command is no longer needed. This also works when
4217 examining core files.
4221 You can specify the number of lines that the `list' command shows.
4224 * New machines supported (host and target)
4226 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4227 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4228 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4230 * New hosts supported (not targets)
4232 IBM RT/PC: romp-ibm-aix or rtpc
4234 * New targets supported (not hosts)
4236 AMD 29000 embedded with COFF a29k-none-coff
4237 AMD 29000 embedded with a.out a29k-none-aout
4238 Ultracomputer remote kernel debug a29k-nyu-kern
4240 * New remote interfaces
4246 *** Changes in GDB-4.0:
4250 Wide output is wrapped at good places to make the output more readable.
4252 Gdb now supports cross-debugging from a host machine of one type to a
4253 target machine of another type. Communication with the target system
4254 is over serial lines. The ``target'' command handles connecting to the
4255 remote system; the ``load'' command will download a program into the
4256 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4257 also supports debugging of realtime processes running under VxWorks,
4258 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4259 stub on the target system.
4261 New CPUs supported include the AMD 29000 and Intel 960.
4263 GDB now reads object files and symbol tables via a ``binary file''
4264 library, which allows a single copy of GDB to debug programs of multiple
4265 object file types such as a.out and coff.
4267 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4268 refcard.dvi and refcard.ps are available to format it).
4271 * Control-Variable user interface simplified
4273 All variables that control the operation of the debugger can be set
4274 by the ``set'' command, and displayed by the ``show'' command.
4276 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4277 ``Show prompt'' produces the response:
4278 Gdb's prompt is new-gdb=>.
4280 What follows are the NEW set commands. The command ``help set'' will
4281 print a complete list of old and new set commands. ``help set FOO''
4282 will give a longer description of the variable FOO. ``show'' will show
4283 all of the variable descriptions and their current settings.
4285 confirm on/off: Enables warning questions for operations that are
4286 hard to recover from, e.g. rerunning the program while
4287 it is already running. Default is ON.
4289 editing on/off: Enables EMACS style command line editing
4290 of input. Previous lines can be recalled with
4291 control-P, the current line can be edited with control-B,
4292 you can search for commands with control-R, etc.
4295 history filename NAME: NAME is where the gdb command history
4296 will be stored. The default is .gdb_history,
4297 or the value of the environment variable
4300 history size N: The size, in commands, of the command history. The
4301 default is 256, or the value of the environment variable
4304 history save on/off: If this value is set to ON, the history file will
4305 be saved after exiting gdb. If set to OFF, the
4306 file will not be saved. The default is OFF.
4308 history expansion on/off: If this value is set to ON, then csh-like
4309 history expansion will be performed on
4310 command line input. The default is OFF.
4312 radix N: Sets the default radix for input and output. It can be set
4313 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4314 in the current radix, so "set radix 10" is always a no-op.
4316 height N: This integer value is the number of lines on a page. Default
4317 is 24, the current `stty rows'' setting, or the ``li#''
4318 setting from the termcap entry matching the environment
4321 width N: This integer value is the number of characters on a line.
4322 Default is 80, the current `stty cols'' setting, or the ``co#''
4323 setting from the termcap entry matching the environment
4326 Note: ``set screensize'' is obsolete. Use ``set height'' and
4327 ``set width'' instead.
4329 print address on/off: Print memory addresses in various command displays,
4330 such as stack traces and structure values. Gdb looks
4331 more ``symbolic'' if you turn this off; it looks more
4332 ``machine level'' with it on. Default is ON.
4334 print array on/off: Prettyprint arrays. New convenient format! Default
4337 print demangle on/off: Print C++ symbols in "source" form if on,
4340 print asm-demangle on/off: Same, for assembler level printouts
4343 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4346 * Support for Epoch Environment.
4348 The epoch environment is a version of Emacs v18 with windowing. One
4349 new command, ``inspect'', is identical to ``print'', except that if you
4350 are running in the epoch environment, the value is printed in its own
4354 * Support for Shared Libraries
4356 GDB can now debug programs and core files that use SunOS shared libraries.
4357 Symbols from a shared library cannot be referenced
4358 before the shared library has been linked with the program (this
4359 happens after you type ``run'' and before the function main() is entered).
4360 At any time after this linking (including when examining core files
4361 from dynamically linked programs), gdb reads the symbols from each
4362 shared library when you type the ``sharedlibrary'' command.
4363 It can be abbreviated ``share''.
4365 sharedlibrary REGEXP: Load shared object library symbols for files
4366 matching a unix regular expression. No argument
4367 indicates to load symbols for all shared libraries.
4369 info sharedlibrary: Status of loaded shared libraries.
4374 A watchpoint stops execution of a program whenever the value of an
4375 expression changes. Checking for this slows down execution
4376 tremendously whenever you are in the scope of the expression, but is
4377 quite useful for catching tough ``bit-spreader'' or pointer misuse
4378 problems. Some machines such as the 386 have hardware for doing this
4379 more quickly, and future versions of gdb will use this hardware.
4381 watch EXP: Set a watchpoint (breakpoint) for an expression.
4383 info watchpoints: Information about your watchpoints.
4385 delete N: Deletes watchpoint number N (same as breakpoints).
4386 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4387 enable N: Re-enables watchpoint number N (same as breakpoints).
4390 * C++ multiple inheritance
4392 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4395 * C++ exception handling
4397 Gdb now supports limited C++ exception handling. Besides the existing
4398 ability to breakpoint on an exception handler, gdb can breakpoint on
4399 the raising of an exception (before the stack is peeled back to the
4402 catch FOO: If there is a FOO exception handler in the dynamic scope,
4403 set a breakpoint to catch exceptions which may be raised there.
4404 Multiple exceptions (``catch foo bar baz'') may be caught.
4406 info catch: Lists all exceptions which may be caught in the
4407 current stack frame.
4410 * Minor command changes
4412 The command ``call func (arg, arg, ...)'' now acts like the print
4413 command, except it does not print or save a value if the function's result
4414 is void. This is similar to dbx usage.
4416 The ``up'' and ``down'' commands now always print the frame they end up
4417 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4418 frames without printing.
4420 * New directory command
4422 'dir' now adds directories to the FRONT of the source search path.
4423 The path starts off empty. Source files that contain debug information
4424 about the directory in which they were compiled can be found even
4425 with an empty path; Sun CC and GCC include this information. If GDB can't
4426 find your source file in the current directory, type "dir .".
4428 * Configuring GDB for compilation
4430 For normal use, type ``./configure host''. See README or gdb.texinfo
4433 GDB now handles cross debugging. If you are remotely debugging between
4434 two different machines, type ``./configure host -target=targ''.
4435 Host is the machine where GDB will run; targ is the machine
4436 where the program that you are debugging will run.