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 * New features in the GNU simulator
123 ** The --map-info flag lists all known core mappings.
125 *** Changes in GDB 7.2
127 * Shared library support for remote targets by default
129 When GDB is configured for a generic, non-OS specific target, like
130 for example, --target=arm-eabi or one of the many *-*-elf targets,
131 GDB now queries remote stubs for loaded shared libraries using the
132 `qXfer:libraries:read' packet. Previously, shared library support
133 was always disabled for such configurations.
137 ** Argument Dependent Lookup (ADL)
139 In C++ ADL lookup directs function search to the namespaces of its
140 arguments even if the namespace has not been imported.
150 Here the compiler will search for `foo' in the namespace of 'b'
151 and find A::foo. GDB now supports this. This construct is commonly
152 used in the Standard Template Library for operators.
154 ** Improved User Defined Operator Support
156 In addition to member operators, GDB now supports lookup of operators
157 defined in a namespace and imported with a `using' directive, operators
158 defined in the global scope, operators imported implicitly from an
159 anonymous namespace, and the ADL operators mentioned in the previous
161 GDB now also supports proper overload resolution for all the previously
162 mentioned flavors of operators.
164 ** static const class members
166 Printing of static const class members that are initialized in the
167 class definition has been fixed.
169 * Windows Thread Information Block access.
171 On Windows targets, GDB now supports displaying the Windows Thread
172 Information Block (TIB) structure. This structure is visible either
173 by using the new command `info w32 thread-information-block' or, by
174 dereferencing the new convenience variable named `$_tlb', a
175 thread-specific pointer to the TIB. This feature is also supported
176 when remote debugging using GDBserver.
180 Static tracepoints are calls in the user program into a tracing
181 library. One such library is a port of the LTTng kernel tracer to
182 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
183 When debugging with GDBserver, GDB now supports combining the GDB
184 tracepoint machinery with such libraries. For example: the user can
185 use GDB to probe a static tracepoint marker (a call from the user
186 program into the tracing library) with the new "strace" command (see
187 "New commands" below). This creates a "static tracepoint" in the
188 breakpoint list, that can be manipulated with the same feature set
189 as fast and regular tracepoints. E.g., collect registers, local and
190 global variables, collect trace state variables, and define
191 tracepoint conditions. In addition, the user can collect extra
192 static tracepoint marker specific data, by collecting the new
193 $_sdata internal variable. When analyzing the trace buffer, you can
194 inspect $_sdata like any other variable available to GDB. For more
195 information, see the "Tracepoints" chapter in GDB user manual. New
196 remote packets have been defined to support static tracepoints, see
197 the "New remote packets" section below.
199 * Better reconstruction of tracepoints after disconnected tracing
201 GDB will attempt to download the original source form of tracepoint
202 definitions when starting a trace run, and then will upload these
203 upon reconnection to the target, resulting in a more accurate
204 reconstruction of the tracepoints that are in use on the target.
208 You can now exercise direct control over the ways that GDB can
209 affect your program. For instance, you can disallow the setting of
210 breakpoints, so that the program can run continuously (assuming
211 non-stop mode). In addition, the "observer" variable is available
212 to switch all of the different controls; in observer mode, GDB
213 cannot affect the target's behavior at all, which is useful for
214 tasks like diagnosing live systems in the field.
216 * The new convenience variable $_thread holds the number of the
223 Return the address of the Windows Thread Information Block of a given thread.
227 In response to several of the tracepoint packets, the target may now
228 also respond with a number of intermediate `qRelocInsn' request
229 packets before the final result packet, to have GDB handle
230 relocating an instruction to execute at a different address. This
231 is particularly useful for stubs that support fast tracepoints. GDB
232 reports support for this feature in the qSupported packet.
236 List static tracepoint markers in the target program.
240 List static tracepoint markers at a given address in the target
243 qXfer:statictrace:read
245 Read the static trace data collected (by a `collect $_sdata'
246 tracepoint action). The remote stub reports support for this packet
247 to gdb's qSupported query.
251 Send the current settings of GDB's permission flags.
255 Send part of the source (textual) form of a tracepoint definition,
256 which includes location, conditional, and action list.
258 * The source command now accepts a -s option to force searching for the
259 script in the source search path even if the script name specifies
262 * New features in the GDB remote stub, GDBserver
264 - GDBserver now support tracepoints (including fast tracepoints, and
265 static tracepoints). The feature is currently supported by the
266 i386-linux and amd64-linux builds. See the "Tracepoints support
267 in gdbserver" section in the manual for more information.
269 GDBserver JIT compiles the tracepoint's conditional agent
270 expression bytecode into native code whenever possible for low
271 overhead dynamic tracepoints conditionals. For such tracepoints,
272 an expression that examines program state is evaluated when the
273 tracepoint is reached, in order to determine whether to capture
274 trace data. If the condition is simple and false, processing the
275 tracepoint finishes very quickly and no data is gathered.
277 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
278 for static tracepoints support.
280 - GDBserver now supports x86_64 Windows 64-bit debugging.
282 * GDB now sends xmlRegisters= in qSupported packet to indicate that
283 it understands register description.
285 * The --batch flag now disables pagination and queries.
287 * X86 general purpose registers
289 GDB now supports reading/writing byte, word and double-word x86
290 general purpose registers directly. This means you can use, say,
291 $ah or $ax to refer, respectively, to the byte register AH and
292 16-bit word register AX that are actually portions of the 32-bit
293 register EAX or 64-bit register RAX.
295 * The `commands' command now accepts a range of breakpoints to modify.
296 A plain `commands' following a command that creates multiple
297 breakpoints affects all the breakpoints set by that command. This
298 applies to breakpoints set by `rbreak', and also applies when a
299 single `break' command creates multiple breakpoints (e.g.,
300 breakpoints on overloaded c++ functions).
302 * The `rbreak' command now accepts a filename specification as part of
303 its argument, limiting the functions selected by the regex to those
304 in the specified file.
306 * Support for remote debugging Windows and SymbianOS shared libraries
307 from Unix hosts has been improved. Non Windows GDB builds now can
308 understand target reported file names that follow MS-DOS based file
309 system semantics, such as file names that include drive letters and
310 use the backslash character as directory separator. This makes it
311 possible to transparently use the "set sysroot" and "set
312 solib-search-path" on Unix hosts to point as host copies of the
313 target's shared libraries. See the new command "set
314 target-file-system-kind" described below, and the "Commands to
315 specify files" section in the user manual for more information.
319 eval template, expressions...
320 Convert the values of one or more expressions under the control
321 of the string template to a command line, and call it.
323 set target-file-system-kind unix|dos-based|auto
324 show target-file-system-kind
325 Set or show the assumed file system kind for target reported file
328 save breakpoints <filename>
329 Save all current breakpoint definitions to a file suitable for use
330 in a later debugging session. To read the saved breakpoint
331 definitions, use the `source' command.
333 `save tracepoints' is a new alias for `save-tracepoints'. The latter
336 info static-tracepoint-markers
337 Display information about static tracepoint markers in the target.
339 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
340 Define a static tracepoint by probing a marker at the given
341 function, line, address, or marker ID.
345 Enable and disable observer mode.
347 set may-write-registers on|off
348 set may-write-memory on|off
349 set may-insert-breakpoints on|off
350 set may-insert-tracepoints on|off
351 set may-insert-fast-tracepoints on|off
352 set may-interrupt on|off
353 Set individual permissions for GDB effects on the target. Note that
354 some of these settings can have undesirable or surprising
355 consequences, particularly when changed in the middle of a session.
356 For instance, disabling the writing of memory can prevent
357 breakpoints from being inserted, cause single-stepping to fail, or
358 even crash your program, if you disable after breakpoints have been
359 inserted. However, GDB should not crash.
361 set record memory-query on|off
362 show record memory-query
363 Control whether to stop the inferior if memory changes caused
364 by an instruction cannot be recorded.
369 The disassemble command now supports "start,+length" form of two arguments.
373 ** GDB now provides a new directory location, called the python directory,
374 where Python scripts written for GDB can be installed. The location
375 of that directory is <data-directory>/python, where <data-directory>
376 is the GDB data directory. For more details, see section `Scripting
377 GDB using Python' in the manual.
379 ** The GDB Python API now has access to breakpoints, symbols, symbol
380 tables, program spaces, inferiors, threads and frame's code blocks.
381 Additionally, GDB Parameters can now be created from the API, and
382 manipulated via set/show in the CLI.
384 ** New functions gdb.target_charset, gdb.target_wide_charset,
385 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
387 ** New exception gdb.GdbError.
389 ** Pretty-printers are now also looked up in the current program space.
391 ** Pretty-printers can now be individually enabled and disabled.
393 ** GDB now looks for names of Python scripts to auto-load in a
394 special section named `.debug_gdb_scripts', in addition to looking
395 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
397 * Tracepoint actions were unified with breakpoint commands. In particular,
398 there are no longer differences in "info break" output for breakpoints and
399 tracepoints and the "commands" command can be used for both tracepoints and
404 ARM Symbian arm*-*-symbianelf*
406 * D language support.
407 GDB now supports debugging programs written in the D programming
410 * GDB now supports the extended ptrace interface for PowerPC which is
411 available since Linux kernel version 2.6.34. This automatically enables
412 any hardware breakpoints and additional hardware watchpoints available in
413 the processor. The old ptrace interface exposes just one hardware
414 watchpoint and no hardware breakpoints.
416 * GDB is now able to use the Data Value Compare (DVC) register available on
417 embedded PowerPC processors to implement in hardware simple watchpoint
418 conditions of the form:
420 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
422 This works in native GDB running on Linux kernels with the extended ptrace
423 interface mentioned above.
425 *** Changes in GDB 7.1
431 GDB now supports importing of namespaces in C++. This enables the
432 user to inspect variables from imported namespaces. Support for
433 namepace aliasing has also been added. So, if a namespace is
434 aliased in the current scope (e.g. namepace C=A; ) the user can
435 print variables using the alias (e.g. (gdb) print C::x).
439 All known bugs relating to the printing of virtual base class were
440 fixed. It is now possible to call overloaded static methods using a
445 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
446 and reinterpret_cast<> are now handled by the C++ expression parser.
450 Xilinx MicroBlaze microblaze-*-*
455 Xilinx MicroBlaze microblaze
458 * Multi-program debugging.
460 GDB now has support for multi-program (a.k.a. multi-executable or
461 multi-exec) debugging. This allows for debugging multiple inferiors
462 simultaneously each running a different program under the same GDB
463 session. See "Debugging Multiple Inferiors and Programs" in the
464 manual for more information. This implied some user visible changes
465 in the multi-inferior support. For example, "info inferiors" now
466 lists inferiors that are not running yet or that have exited
467 already. See also "New commands" and "New options" below.
469 * New tracing features
471 GDB's tracepoint facility now includes several new features:
473 ** Trace state variables
475 GDB tracepoints now include support for trace state variables, which
476 are variables managed by the target agent during a tracing
477 experiment. They are useful for tracepoints that trigger each
478 other, so for instance one tracepoint can count hits in a variable,
479 and then a second tracepoint has a condition that is true when the
480 count reaches a particular value. Trace state variables share the
481 $-syntax of GDB convenience variables, and can appear in both
482 tracepoint actions and condition expressions. Use the "tvariable"
483 command to create, and "info tvariables" to view; see "Trace State
484 Variables" in the manual for more detail.
488 GDB now includes an option for defining fast tracepoints, which
489 targets may implement more efficiently, such as by installing a jump
490 into the target agent rather than a trap instruction. The resulting
491 speedup can be by two orders of magnitude or more, although the
492 tradeoff is that some program locations on some target architectures
493 might not allow fast tracepoint installation, for instance if the
494 instruction to be replaced is shorter than the jump. To request a
495 fast tracepoint, use the "ftrace" command, with syntax identical to
496 the regular trace command.
498 ** Disconnected tracing
500 It is now possible to detach GDB from the target while it is running
501 a trace experiment, then reconnect later to see how the experiment
502 is going. In addition, a new variable disconnected-tracing lets you
503 tell the target agent whether to continue running a trace if the
504 connection is lost unexpectedly.
508 GDB now has the ability to save the trace buffer into a file, and
509 then use that file as a target, similarly to you can do with
510 corefiles. You can select trace frames, print data that was
511 collected in them, and use tstatus to display the state of the
512 tracing run at the moment that it was saved. To create a trace
513 file, use "tsave <filename>", and to use it, do "target tfile
516 ** Circular trace buffer
518 You can ask the target agent to handle the trace buffer as a
519 circular buffer, discarding the oldest trace frames to make room for
520 newer ones, by setting circular-trace-buffer to on. This feature may
521 not be available for all target agents.
526 The disassemble command, when invoked with two arguments, now requires
527 the arguments to be comma-separated.
530 The info variables command now displays variable definitions. Files
531 which only declare a variable are not shown.
534 The source command is now capable of sourcing Python scripts.
535 This feature is dependent on the debugger being build with Python
538 Related to this enhancement is also the introduction of a new command
539 "set script-extension" (see below).
541 * New commands (for set/show, see "New options" below)
543 record save [<FILENAME>]
544 Save a file (in core file format) containing the process record
545 execution log for replay debugging at a later time.
547 record restore <FILENAME>
548 Restore the process record execution log that was saved at an
549 earlier time, for replay debugging.
551 add-inferior [-copies <N>] [-exec <FILENAME>]
554 clone-inferior [-copies <N>] [ID]
555 Make a new inferior ready to execute the same program another
561 maint info program-spaces
562 List the program spaces loaded into GDB.
564 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
565 show remote interrupt-sequence
566 Allow the user to select one of ^C, a BREAK signal or BREAK-g
567 as the sequence to the remote target in order to interrupt the execution.
568 Ctrl-C is a default. Some system prefers BREAK which is high level of
569 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
570 Magic SysRq g. It is BREAK signal and character 'g'.
572 set remote interrupt-on-connect [on | off]
573 show remote interrupt-on-connect
574 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
575 remote target when gdb connects to it. This is needed when you debug
578 set remotebreak [on | off]
580 Deprecated. Use "set/show remote interrupt-sequence" instead.
582 tvariable $NAME [ = EXP ]
583 Create or modify a trace state variable.
586 List trace state variables and their values.
588 delete tvariable $NAME ...
589 Delete one or more trace state variables.
592 Evaluate the given expressions without collecting anything into the
593 trace buffer. (Valid in tracepoint actions only.)
595 ftrace FN / FILE:LINE / *ADDR
596 Define a fast tracepoint at the given function, line, or address.
598 * New expression syntax
600 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
601 GDB now parses 0b101010 identically with 42.
605 set follow-exec-mode new|same
606 show follow-exec-mode
607 Control whether GDB reuses the same inferior across an exec call or
608 creates a new one. This is useful to be able to restart the old
609 executable after the inferior having done an exec call.
611 set default-collect EXPR, ...
613 Define a list of expressions to be collected at each tracepoint.
614 This is a useful way to ensure essential items are not overlooked,
615 such as registers or a critical global variable.
617 set disconnected-tracing
618 show disconnected-tracing
619 If set to 1, the target is instructed to continue tracing if it
620 loses its connection to GDB. If 0, the target is to stop tracing
623 set circular-trace-buffer
624 show circular-trace-buffer
625 If set to on, the target is instructed to use a circular trace buffer
626 and discard the oldest trace frames instead of stopping the trace due
627 to a full trace buffer. If set to off, the trace stops when the buffer
628 fills up. Some targets may not support this.
630 set script-extension off|soft|strict
631 show script-extension
632 If set to "off", the debugger does not perform any script language
633 recognition, and all sourced files are assumed to be GDB scripts.
634 If set to "soft" (the default), files are sourced according to
635 filename extension, falling back to GDB scripts if the first
637 If set to "strict", files are sourced according to filename extension.
639 set ada trust-PAD-over-XVS on|off
640 show ada trust-PAD-over-XVS
641 If off, activate a workaround against a bug in the debugging information
642 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
643 the GCC sources for more information about the GNAT encoding and
644 PAD types in particular). It is always safe to set this option to
645 off, but this introduces a slight performance penalty. The default
648 * Python API Improvements
650 ** GDB provides the new class gdb.LazyString. This is useful in
651 some pretty-printing cases. The new method gdb.Value.lazy_string
652 provides a simple way to create objects of this type.
654 ** The fields returned by gdb.Type.fields now have an
655 `is_base_class' attribute.
657 ** The new method gdb.Type.range returns the range of an array type.
659 ** The new method gdb.parse_and_eval can be used to parse and
660 evaluate an expression.
665 Define a trace state variable.
668 Get the current value of a trace state variable.
671 Set desired tracing behavior upon disconnection.
674 Set the trace buffer to be linear or circular.
677 Get data about the tracepoints currently in use.
681 Process record now works correctly with hardware watchpoints.
683 Multiple bug fixes have been made to the mips-irix port, making it
684 much more reliable. In particular:
685 - Debugging threaded applications is now possible again. Previously,
686 GDB would hang while starting the program, or while waiting for
687 the program to stop at a breakpoint.
688 - Attaching to a running process no longer hangs.
689 - An error occurring while loading a core file has been fixed.
690 - Changing the value of the PC register now works again. This fixes
691 problems observed when using the "jump" command, or when calling
692 a function from GDB, or even when assigning a new value to $pc.
693 - With the "finish" and "return" commands, the return value for functions
694 returning a small array is now correctly printed.
695 - It is now possible to break on shared library code which gets executed
696 during a shared library init phase (code executed while executing
697 their .init section). Previously, the breakpoint would have no effect.
698 - GDB is now able to backtrace through the signal handler for
699 non-threaded programs.
701 PIE (Position Independent Executable) programs debugging is now supported.
702 This includes debugging execution of PIC (Position Independent Code) shared
703 libraries although for that, it should be possible to run such libraries as an
706 *** Changes in GDB 7.0
708 * GDB now has an interface for JIT compilation. Applications that
709 dynamically generate code can create symbol files in memory and register
710 them with GDB. For users, the feature should work transparently, and
711 for JIT developers, the interface is documented in the GDB manual in the
712 "JIT Compilation Interface" chapter.
714 * Tracepoints may now be conditional. The syntax is as for
715 breakpoints; either an "if" clause appended to the "trace" command,
716 or the "condition" command is available. GDB sends the condition to
717 the target for evaluation using the same bytecode format as is used
718 for tracepoint actions.
720 * The disassemble command now supports: an optional /r modifier, print the
721 raw instructions in hex as well as in symbolic form, and an optional /m
722 modifier to print mixed source+assembly.
724 * Process record and replay
726 In a architecture environment that supports ``process record and
727 replay'', ``process record and replay'' target can record a log of
728 the process execution, and replay it with both forward and reverse
731 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
732 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
733 set execution-direction {forward|reverse}, for targets that support
736 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
737 feature is available with a native GDB running on kernel version
740 * GDB now has support for multi-byte and wide character sets on the
741 target. Strings whose character type is wchar_t, char16_t, or
742 char32_t are now correctly printed. GDB supports wide- and unicode-
743 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
744 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
745 `printf'. This feature requires iconv to work properly; if your
746 system does not have a working iconv, GDB can use GNU libiconv. See
747 the installation instructions for more information.
749 * GDB now supports automatic retrieval of shared library files from
750 remote targets. To use this feature, specify a system root that begins
751 with the `remote:' prefix, either via the `set sysroot' command or via
752 the `--with-sysroot' configure-time option.
754 * "info sharedlibrary" now takes an optional regex of libraries to show,
755 and it now reports if a shared library has no debugging information.
757 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
758 now complete on file names.
760 * When completing in expressions, gdb will attempt to limit
761 completions to allowable structure or union fields, where appropriate.
762 For instance, consider:
764 # struct example { int f1; double f2; };
765 # struct example variable;
768 If the user types TAB at the end of this command line, the available
769 completions will be "f1" and "f2".
771 * Inlined functions are now supported. They show up in backtraces, and
772 the "step", "next", and "finish" commands handle them automatically.
774 * GDB now supports the token-splicing (##) and stringification (#)
775 operators when expanding macros. It also supports variable-arity
778 * GDB now supports inspecting extra signal information, exported by
779 the new $_siginfo convenience variable. The feature is currently
780 implemented on linux ARM, i386 and amd64.
782 * GDB can now display the VFP floating point registers and NEON vector
783 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
784 can provide these registers (requires Linux 2.6.30 or later). Remote
785 and simulator targets may also provide them.
790 Search memory for a sequence of bytes.
793 Turn off `+'/`-' protocol acknowledgments to permit more efficient
794 operation over reliable transport links. Use of this packet is
795 controlled by the `set remote noack-packet' command.
798 Kill the process with the specified process ID. Use this in preference
799 to `k' when multiprocess protocol extensions are supported.
802 Obtains additional operating system information
806 Read or write additional signal information.
808 * Removed remote protocol undocumented extension
810 An undocumented extension to the remote protocol's `S' stop reply
811 packet that permited the stub to pass a process id was removed.
812 Remote servers should use the `T' stop reply packet instead.
814 * GDB now supports multiple function calling conventions according to the
815 DWARF-2 DW_AT_calling_convention function attribute.
817 * The SH target utilizes the aforementioned change to distinguish between gcc
818 and Renesas calling convention. It also adds the new CLI commands
819 `set/show sh calling-convention'.
821 * GDB can now read compressed debug sections, as produced by GNU gold
822 with the --compress-debug-sections=zlib flag.
824 * 64-bit core files are now supported on AIX.
826 * Thread switching is now supported on Tru64.
828 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
829 which will be allocated using malloc later in program execution.
831 * The qXfer:libraries:read remote procotol packet now allows passing a
832 list of section offsets.
834 * On GNU/Linux, GDB can now attach to stopped processes. Several race
835 conditions handling signals delivered during attach or thread creation
836 have also been fixed.
838 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
839 From the user's standpoint, all unqualified instances of True and False
840 are treated as the standard definitions, regardless of context.
842 * GDB now parses C++ symbol and type names more flexibly. For
845 template<typename T> class C { };
848 GDB will now correctly handle all of:
850 ptype C<char const *>
852 ptype C<const char *>
855 * New features in the GDB remote stub, gdbserver
857 - The "--wrapper" command-line argument tells gdbserver to use a
858 wrapper program to launch programs for debugging.
860 - On PowerPC and S/390 targets, it is now possible to use a single
861 gdbserver executable to debug both 32-bit and 64-bit programs.
862 (This requires gdbserver itself to be built as a 64-bit executable.)
864 - gdbserver uses the new noack protocol mode for TCP connections to
865 reduce communications latency, if also supported and enabled in GDB.
867 - Support for the sparc64-linux-gnu target is now included in
870 - The amd64-linux build of gdbserver now supports debugging both
871 32-bit and 64-bit programs.
873 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
874 now support hardware watchpoints, and will use them automatically
879 GDB now has support for scripting using Python. Whether this is
880 available is determined at configure time.
882 New GDB commands can now be written in Python.
884 * Ada tasking support
886 Ada tasks can now be inspected in GDB. The following commands have
890 Print the list of Ada tasks.
892 Print detailed information about task number N.
894 Print the task number of the current task.
896 Switch the context of debugging to task number N.
898 * Support for user-defined prefixed commands. The "define" command can
899 add new commands to existing prefixes, e.g. "target".
901 * Multi-inferior, multi-process debugging.
903 GDB now has generalized support for multi-inferior debugging. See
904 "Debugging Multiple Inferiors" in the manual for more information.
905 Although availability still depends on target support, the command
906 set is more uniform now. The GNU/Linux specific multi-forks support
907 has been migrated to this new framework. This implied some user
908 visible changes; see "New commands" and also "Removed commands"
911 * Target descriptions can now describe the target OS ABI. See the
912 "Target Description Format" section in the user manual for more
915 * Target descriptions can now describe "compatible" architectures
916 to indicate that the target can execute applications for a different
917 architecture in addition to those for the main target architecture.
918 See the "Target Description Format" section in the user manual for
921 * Multi-architecture debugging.
923 GDB now includes general supports for debugging applications on
924 hybrid systems that use more than one single processor architecture
925 at the same time. Each such hybrid architecture still requires
926 specific support to be added. The only hybrid architecture supported
927 in this version of GDB is the Cell Broadband Engine.
929 * GDB now supports integrated debugging of Cell/B.E. applications that
930 use both the PPU and SPU architectures. To enable support for hybrid
931 Cell/B.E. debugging, you need to configure GDB to support both the
932 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
933 --enable-targets configure option.
935 * Non-stop mode debugging.
937 For some targets, GDB now supports an optional mode of operation in
938 which you can examine stopped threads while other threads continue
939 to execute freely. This is referred to as non-stop mode, with the
940 old mode referred to as all-stop mode. See the "Non-Stop Mode"
941 section in the user manual for more information.
943 To be able to support remote non-stop debugging, a remote stub needs
944 to implement the non-stop mode remote protocol extensions, as
945 described in the "Remote Non-Stop" section of the user manual. The
946 GDB remote stub, gdbserver, has been adjusted to support these
947 extensions on linux targets.
949 * New commands (for set/show, see "New options" below)
951 catch syscall [NAME(S) | NUMBER(S)]
952 Catch system calls. Arguments, which should be names of system
953 calls or their numbers, mean catch only those syscalls. Without
954 arguments, every syscall will be caught. When the inferior issues
955 any of the specified syscalls, GDB will stop and announce the system
956 call, both when it is called and when its call returns. This
957 feature is currently available with a native GDB running on the
958 Linux Kernel, under the following architectures: x86, x86_64,
959 PowerPC and PowerPC64.
961 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
963 Search memory for a sequence of bytes.
965 maint set python print-stack
966 maint show python print-stack
967 Show a stack trace when an error is encountered in a Python script.
970 Invoke CODE by passing it to the Python interpreter.
975 These allow macros to be defined, undefined, and listed
979 Show operating system information about processes.
982 List the inferiors currently under GDB's control.
985 Switch focus to inferior number NUM.
988 Detach from inferior number NUM.
991 Kill inferior number NUM.
996 show spu stop-on-load
997 Control whether to stop for new SPE threads during Cell/B.E. debugging.
999 set spu auto-flush-cache
1000 show spu auto-flush-cache
1001 Control whether to automatically flush the software-managed cache
1002 during Cell/B.E. debugging.
1004 set sh calling-convention
1005 show sh calling-convention
1006 Control the calling convention used when calling SH target functions.
1009 show debug timestamp
1010 Control display of timestamps with GDB debugging output.
1012 set disassemble-next-line
1013 show disassemble-next-line
1014 Control display of disassembled source lines or instructions when
1017 set remote noack-packet
1018 show remote noack-packet
1019 Set/show the use of remote protocol QStartNoAckMode packet. See above
1020 under "New remote packets."
1022 set remote query-attached-packet
1023 show remote query-attached-packet
1024 Control use of remote protocol `qAttached' (query-attached) packet.
1026 set remote read-siginfo-object
1027 show remote read-siginfo-object
1028 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1031 set remote write-siginfo-object
1032 show remote write-siginfo-object
1033 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1036 set remote reverse-continue
1037 show remote reverse-continue
1038 Control use of remote protocol 'bc' (reverse-continue) packet.
1040 set remote reverse-step
1041 show remote reverse-step
1042 Control use of remote protocol 'bs' (reverse-step) packet.
1044 set displaced-stepping
1045 show displaced-stepping
1046 Control displaced stepping mode. Displaced stepping is a way to
1047 single-step over breakpoints without removing them from the debuggee.
1048 Also known as "out-of-line single-stepping".
1051 show debug displaced
1052 Control display of debugging info for displaced stepping.
1054 maint set internal-error
1055 maint show internal-error
1056 Control what GDB does when an internal error is detected.
1058 maint set internal-warning
1059 maint show internal-warning
1060 Control what GDB does when an internal warning is detected.
1065 Use a wrapper program to launch programs for debugging.
1067 set multiple-symbols (all|ask|cancel)
1068 show multiple-symbols
1069 The value of this variable can be changed to adjust the debugger behavior
1070 when an expression or a breakpoint location contains an ambiguous symbol
1071 name (an overloaded function name, for instance).
1073 set breakpoint always-inserted
1074 show breakpoint always-inserted
1075 Keep breakpoints always inserted in the target, as opposed to inserting
1076 them when resuming the target, and removing them when the target stops.
1077 This option can improve debugger performance on slow remote targets.
1079 set arm fallback-mode (arm|thumb|auto)
1080 show arm fallback-mode
1081 set arm force-mode (arm|thumb|auto)
1083 These commands control how ARM GDB determines whether instructions
1084 are ARM or Thumb. The default for both settings is auto, which uses
1085 the current CPSR value for instructions without symbols; previous
1086 versions of GDB behaved as if "set arm fallback-mode arm".
1088 set disable-randomization
1089 show disable-randomization
1090 Standalone programs run with the virtual address space randomization enabled
1091 by default on some platforms. This option keeps the addresses stable across
1092 multiple debugging sessions.
1096 Control whether other threads are stopped or not when some thread hits
1101 Requests that asynchronous execution is enabled in the target, if available.
1102 In this case, it's possible to resume target in the background, and interact
1103 with GDB while the target is running. "show target-async" displays the
1104 current state of asynchronous execution of the target.
1106 set target-wide-charset
1107 show target-wide-charset
1108 The target-wide-charset is the name of the character set that GDB
1109 uses when printing characters whose type is wchar_t.
1111 set tcp auto-retry (on|off)
1113 set tcp connect-timeout
1114 show tcp connect-timeout
1115 These commands allow GDB to retry failed TCP connections to a remote stub
1116 with a specified timeout period; this is useful if the stub is launched
1117 in parallel with GDB but may not be ready to accept connections immediately.
1119 set libthread-db-search-path
1120 show libthread-db-search-path
1121 Control list of directories which GDB will search for appropriate
1124 set schedule-multiple (on|off)
1125 show schedule-multiple
1126 Allow GDB to resume all threads of all processes or only threads of
1127 the current process.
1131 Use more aggressive caching for accesses to the stack. This improves
1132 performance of remote debugging (particularly backtraces) without
1133 affecting correctness.
1135 set interactive-mode (on|off|auto)
1136 show interactive-mode
1137 Control whether GDB runs in interactive mode (on) or not (off).
1138 When in interactive mode, GDB waits for the user to answer all
1139 queries. Otherwise, GDB does not wait and assumes the default
1140 answer. When set to auto (the default), GDB determines which
1141 mode to use based on the stdin settings.
1146 For program forks, this is replaced by the new more generic `info
1147 inferiors' command. To list checkpoints, you can still use the
1148 `info checkpoints' command, which was an alias for the `info forks'
1152 Replaced by the new `inferior' command. To switch between
1153 checkpoints, you can still use the `restart' command, which was an
1154 alias for the `fork' command.
1157 This is removed, since some targets don't have a notion of
1158 processes. To switch between processes, you can still use the
1159 `inferior' command using GDB's own inferior number.
1162 For program forks, this is replaced by the new more generic `kill
1163 inferior' command. To delete a checkpoint, you can still use the
1164 `delete checkpoint' command, which was an alias for the `delete
1168 For program forks, this is replaced by the new more generic `detach
1169 inferior' command. To detach a checkpoint, you can still use the
1170 `detach checkpoint' command, which was an alias for the `detach
1173 * New native configurations
1175 x86/x86_64 Darwin i[34567]86-*-darwin*
1177 x86_64 MinGW x86_64-*-mingw*
1181 Lattice Mico32 lm32-*
1182 x86 DICOS i[34567]86-*-dicos*
1183 x86_64 DICOS x86_64-*-dicos*
1186 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1187 (mingw32ce) debugging.
1193 These commands were actually not implemented on any target.
1195 *** Changes in GDB 6.8
1197 * New native configurations
1199 NetBSD/hppa hppa*-*netbsd*
1200 Xtensa GNU/Linux xtensa*-*-linux*
1204 NetBSD/hppa hppa*-*-netbsd*
1205 Xtensa GNU/Lunux xtensa*-*-linux*
1207 * Change in command line behavior -- corefiles vs. process ids.
1209 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1210 attaching to process NUMBER fails, GDB no longer attempts to open a
1211 core file named NUMBER. Attaching to a program using the -c option
1212 is no longer supported. Instead, use the '-p' or '--pid' options.
1214 * GDB can now be built as a native debugger for debugging Windows x86
1215 (mingw32) Portable Executable (PE) programs.
1217 * Pending breakpoints no longer change their number when their address
1220 * GDB now supports breakpoints with multiple locations,
1221 including breakpoints on C++ constructors, inside C++ templates,
1222 and in inlined functions.
1224 * GDB's ability to debug optimized code has been improved. GDB more
1225 accurately identifies function bodies and lexical blocks that occupy
1226 more than one contiguous range of addresses.
1228 * Target descriptions can now describe registers for PowerPC.
1230 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1231 registers on PowerPC targets.
1233 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1234 targets even when the libthread_db library is not available.
1236 * The GDB remote stub, gdbserver, now supports the new file transfer
1237 commands (remote put, remote get, and remote delete).
1239 * The GDB remote stub, gdbserver, now supports run and attach in
1240 extended-remote mode.
1242 * hppa*64*-*-hpux11* target broken
1243 The debugger is unable to start a program and fails with the following
1244 error: "Error trying to get information about dynamic linker".
1245 The gdb-6.7 release is also affected.
1247 * GDB now supports the --enable-targets= configure option to allow
1248 building a single GDB executable that supports multiple remote
1249 target architectures.
1251 * GDB now supports debugging C and C++ programs which use the
1252 Decimal Floating Point extension. In addition, the PowerPC target
1253 now has a set of pseudo-registers to inspect decimal float values
1254 stored in two consecutive float registers.
1256 * The -break-insert MI command can optionally create pending
1259 * Improved support for debugging Ada
1260 Many improvements to the Ada language support have been made. These
1262 - Better support for Ada2005 interface types
1263 - Improved handling of arrays and slices in general
1264 - Better support for Taft-amendment types
1265 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1267 - Improved command completion in Ada
1270 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1275 set print frame-arguments (all|scalars|none)
1276 show print frame-arguments
1277 The value of this variable can be changed to control which argument
1278 values should be printed by the debugger when displaying a frame.
1283 Transfer files to and from a remote target, and delete remote files.
1290 Transfer files to and from a remote target, and delete remote files.
1292 * New remote packets
1299 Open, close, read, write, and delete files on the remote system.
1302 Attach to an existing process on the remote system, in extended-remote
1306 Run a new process on the remote system, in extended-remote mode.
1308 *** Changes in GDB 6.7
1310 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1311 bfd, libiberty and opcodes, as revealed by static analysis donated by
1312 Coverity, Inc. (http://scan.coverity.com).
1314 * When looking up multiply-defined global symbols, GDB will now prefer the
1315 symbol definition in the current shared library if it was built using the
1316 -Bsymbolic linker option.
1318 * When the Text User Interface (TUI) is not configured, GDB will now
1319 recognize the -tui command-line option and print a message that the TUI
1322 * The GDB remote stub, gdbserver, now has lower overhead for high
1323 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1325 * GDB for MIPS targets now autodetects whether a remote target provides
1326 32-bit or 64-bit register values.
1328 * Support for C++ member pointers has been improved.
1330 * GDB now understands XML target descriptions, which specify the
1331 target's overall architecture. GDB can read a description from
1332 a local file or over the remote serial protocol.
1334 * Vectors of single-byte data use a new integer type which is not
1335 automatically displayed as character or string data.
1337 * The /s format now works with the print command. It displays
1338 arrays of single-byte integers and pointers to single-byte integers
1341 * Target descriptions can now describe target-specific registers,
1342 for architectures which have implemented the support (currently
1343 only ARM, M68K, and MIPS).
1345 * GDB and the GDB remote stub, gdbserver, now support the XScale
1348 * The GDB remote stub, gdbserver, has been updated to support
1349 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1350 has been rewritten to use the standard GDB remote protocol.
1352 * GDB can now step into C++ functions which are called through thunks.
1354 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1356 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1357 layout. It also supports a TextSeg= and DataSeg= response when only
1358 segment base addresses (rather than offsets) are available.
1360 * The /i format now outputs any trailing branch delay slot instructions
1361 immediately following the last instruction within the count specified.
1363 * The GDB remote protocol "T" stop reply packet now supports a
1364 "library" response. Combined with the new "qXfer:libraries:read"
1365 packet, this response allows GDB to debug shared libraries on targets
1366 where the operating system manages the list of loaded libraries (e.g.
1367 Windows and SymbianOS).
1369 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1370 (DLLs) on Windows and Windows CE targets.
1372 * GDB now supports a faster verification that a .debug file matches its binary
1373 according to its build-id signature, if the signature is present.
1379 Enable or disable hardware flow control (RTS/CTS) on the serial port
1380 when debugging using remote targets.
1382 set mem inaccessible-by-default
1383 show mem inaccessible-by-default
1384 If the target supplies a memory map, for instance via the remote
1385 protocol's "qXfer:memory-map:read" packet, setting this variable
1386 prevents GDB from accessing memory outside the memory map. This
1387 is useful for targets with memory mapped registers or which react
1388 badly to accesses of unmapped address space.
1390 set breakpoint auto-hw
1391 show breakpoint auto-hw
1392 If the target supplies a memory map, for instance via the remote
1393 protocol's "qXfer:memory-map:read" packet, setting this variable
1394 lets GDB use hardware breakpoints automatically for memory regions
1395 where it can not use software breakpoints. This covers both the
1396 "break" command and internal breakpoints used for other commands
1397 including "next" and "finish".
1400 catch exception unhandled
1401 Stop the program execution when Ada exceptions are raised.
1404 Stop the program execution when an Ada assertion failed.
1408 Set an alternate system root for target files. This is a more
1409 general version of "set solib-absolute-prefix", which is now
1410 an alias to "set sysroot".
1413 Provide extended SPU facility status information. This set of
1414 commands is available only when debugging the Cell/B.E. SPU
1417 * New native configurations
1419 OpenBSD/sh sh*-*openbsd*
1422 unset tdesc filename
1424 Use the specified local file as an XML target description, and do
1425 not query the target for its built-in description.
1429 OpenBSD/sh sh*-*-openbsd*
1430 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1431 Toshiba Media Processor mep-elf
1433 * New remote packets
1436 Ignore the specified signals; pass them directly to the debugged program
1437 without stopping other threads or reporting them to GDB.
1439 qXfer:features:read:
1440 Read an XML target description from the target, which describes its
1445 Read or write contents of an spufs file on the target system. These
1446 packets are available only on the Cell/B.E. SPU architecture.
1448 qXfer:libraries:read:
1449 Report the loaded shared libraries. Combined with new "T" packet
1450 response, this packet allows GDB to debug shared libraries on
1451 targets where the operating system manages the list of loaded
1452 libraries (e.g. Windows and SymbianOS).
1456 Support for these obsolete configurations has been removed.
1464 i[34567]86-*-lynxos*
1465 i[34567]86-*-netware*
1466 i[34567]86-*-sco3.2v5*
1467 i[34567]86-*-sco3.2v4*
1469 i[34567]86-*-sysv4.2*
1472 i[34567]86-*-unixware2*
1473 i[34567]86-*-unixware*
1482 * Other removed features
1489 Various m68k-only ROM monitors.
1496 Various Renesas ROM monitors and debugging interfaces for SH and
1501 Support for a Macraigor serial interface to on-chip debugging.
1502 GDB does not directly support the newer parallel or USB
1507 A debug information format. The predecessor to DWARF 2 and
1508 DWARF 3, which are still supported.
1510 Support for the HP aCC compiler on HP-UX/PA-RISC
1512 SOM-encapsulated symbolic debugging information, automatic
1513 invocation of pxdb, and the aCC custom C++ ABI. This does not
1514 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1515 with aCC can still be debugged on an assembly level.
1517 MIPS ".pdr" sections
1519 A MIPS-specific format used to describe stack frame layout
1520 in debugging information.
1524 GDB could work with an older version of Guile to debug
1525 the interpreter and Scheme programs running in it.
1527 set mips stack-arg-size
1528 set mips saved-gpreg-size
1530 Use "set mips abi" to control parameter passing for MIPS.
1532 *** Changes in GDB 6.6
1537 Cell Broadband Engine SPU spu-elf
1539 * GDB can now be configured as a cross-debugger targeting native Windows
1540 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1541 running on a Windows system over TCP/IP to debug Windows programs.
1543 * The GDB remote stub, gdbserver, has been updated to support Windows and
1544 Cygwin debugging. Both single-threaded and multi-threaded programs are
1547 * The "set trust-readonly-sections" command works again. This command was
1548 broken in GDB 6.3, 6.4, and 6.5.
1550 * The "load" command now supports writing to flash memory, if the remote
1551 stub provides the required support.
1553 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1554 longer requires symbolic debug information (e.g. DWARF-2).
1559 unset substitute-path
1560 show substitute-path
1561 Manage a list of substitution rules that GDB uses to rewrite the name
1562 of the directories where the sources are located. This can be useful
1563 for instance when the sources were moved to a different location
1564 between compilation and debugging.
1568 Print each CLI command as it is executed. Each command is prefixed with
1569 a number of `+' symbols representing the nesting depth.
1570 The source command now has a `-v' option to enable the same feature.
1574 The ARM Demon monitor support (RDP protocol, "target rdp").
1576 Kernel Object Display, an embedded debugging feature which only worked with
1577 an obsolete version of Cisco IOS.
1579 The 'set download-write-size' and 'show download-write-size' commands.
1581 * New remote packets
1584 Tell a stub about GDB client features, and request remote target features.
1585 The first feature implemented is PacketSize, which allows the target to
1586 specify the size of packets it can handle - to minimize the number of
1587 packets required and improve performance when connected to a remote
1591 Fetch an OS auxilliary vector from the remote stub. This packet is a
1592 more efficient replacement for qPart:auxv:read.
1594 qXfer:memory-map:read:
1595 Fetch a memory map from the remote stub, including information about
1596 RAM, ROM, and flash memory devices.
1601 Erase and program a flash memory device.
1603 * Removed remote packets
1606 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1607 used it, and only gdbserver implemented it.
1609 *** Changes in GDB 6.5
1613 Renesas M32C/M16C m32c-elf
1615 Morpho Technologies ms1 ms1-elf
1619 init-if-undefined Initialize a convenience variable, but
1620 only if it doesn't already have a value.
1622 The following commands are presently only implemented for native GNU/Linux:
1624 checkpoint Save a snapshot of the program state.
1626 restart <n> Return the program state to a
1627 previously saved state.
1629 info checkpoints List currently saved checkpoints.
1631 delete-checkpoint <n> Delete a previously saved checkpoint.
1633 set|show detach-on-fork Tell gdb whether to detach from a newly
1634 forked process, or to keep debugging it.
1636 info forks List forks of the user program that
1637 are available to be debugged.
1639 fork <n> Switch to debugging one of several
1640 forks of the user program that are
1641 available to be debugged.
1643 delete-fork <n> Delete a fork from the list of forks
1644 that are available to be debugged (and
1645 kill the forked process).
1647 detach-fork <n> Delete a fork from the list of forks
1648 that are available to be debugged (and
1649 allow the process to continue).
1653 Morpho Technologies ms2 ms1-elf
1655 * Improved Windows host support
1657 GDB now builds as a cross debugger hosted on i686-mingw32, including
1658 native console support, and remote communications using either
1659 network sockets or serial ports.
1661 * Improved Modula-2 language support
1663 GDB can now print most types in the Modula-2 syntax. This includes:
1664 basic types, set types, record types, enumerated types, range types,
1665 pointer types and ARRAY types. Procedure var parameters are correctly
1666 printed and hexadecimal addresses and character constants are also
1667 written in the Modula-2 syntax. Best results can be obtained by using
1668 GNU Modula-2 together with the -gdwarf-2 command line option.
1672 The ARM rdi-share module.
1674 The Netware NLM debug server.
1676 *** Changes in GDB 6.4
1678 * New native configurations
1680 OpenBSD/arm arm*-*-openbsd*
1681 OpenBSD/mips64 mips64-*-openbsd*
1685 Morpho Technologies ms1 ms1-elf
1687 * New command line options
1689 --batch-silent As for --batch, but totally silent.
1690 --return-child-result The debugger will exist with the same value
1691 the child (debugged) program exited with.
1692 --eval-command COMMAND, -ex COMMAND
1693 Execute a single GDB CLI command. This may be
1694 specified multiple times and in conjunction
1695 with the --command (-x) option.
1697 * Deprecated commands removed
1699 The following commands, that were deprecated in 2000, have been
1703 set|show arm disassembly-flavor set|show arm disassembler
1704 othernames set arm disassembler
1705 set|show remotedebug set|show debug remote
1706 set|show archdebug set|show debug arch
1707 set|show eventdebug set|show debug event
1710 * New BSD user-level threads support
1712 It is now possible to debug programs using the user-level threads
1713 library on OpenBSD and FreeBSD. Currently supported (target)
1716 FreeBSD/amd64 x86_64-*-freebsd*
1717 FreeBSD/i386 i386-*-freebsd*
1718 OpenBSD/i386 i386-*-openbsd*
1720 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1721 are not yet supported.
1723 * New support for Matsushita MN10300 w/sim added
1724 (Work in progress). mn10300-elf.
1726 * REMOVED configurations and files
1728 VxWorks and the XDR protocol *-*-vxworks
1729 Motorola MCORE mcore-*-*
1730 National Semiconductor NS32000 ns32k-*-*
1732 * New "set print array-indexes" command
1734 After turning this setting "on", GDB prints the index of each element
1735 when displaying arrays. The default is "off" to preserve the previous
1738 * VAX floating point support
1740 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1742 * User-defined command support
1744 In addition to using $arg0..$arg9 for argument passing, it is now possible
1745 to use $argc to determine now many arguments have been passed. See the
1746 section on user-defined commands in the user manual for more information.
1748 *** Changes in GDB 6.3:
1750 * New command line option
1752 GDB now accepts -l followed by a number to set the timeout for remote
1755 * GDB works with GCC -feliminate-dwarf2-dups
1757 GDB now supports a more compact representation of DWARF-2 debug
1758 information using DW_FORM_ref_addr references. These are produced
1759 by GCC with the option -feliminate-dwarf2-dups and also by some
1760 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1761 to use -feliminate-dwarf2-dups.
1763 * Internationalization
1765 When supported by the host system, GDB will be built with
1766 internationalization (libintl). The task of marking up the sources is
1767 continued, we're looking forward to our first translation.
1771 Initial support for debugging programs compiled with the GNAT
1772 implementation of the Ada programming language has been integrated
1773 into GDB. In this release, support is limited to expression evaluation.
1775 * New native configurations
1777 GNU/Linux/m32r m32r-*-linux-gnu
1781 GDB's remote protocol now includes support for the 'p' packet. This
1782 packet is used to fetch individual registers from a remote inferior.
1784 * END-OF-LIFE registers[] compatibility module
1786 GDB's internal register infrastructure has been completely rewritten.
1787 The new infrastructure making possible the implementation of key new
1788 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1791 GDB 6.3 will be the last release to include the the registers[]
1792 compatibility module that allowed out-of-date configurations to
1793 continue to work. This change directly impacts the following
1803 powerpc bdm protocol
1805 Unless there is activity to revive these configurations, they will be
1806 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1808 * OBSOLETE configurations and files
1810 Configurations that have been declared obsolete in this release have
1811 been commented out. Unless there is activity to revive these
1812 configurations, the next release of GDB will have their sources
1813 permanently REMOVED.
1822 *** Changes in GDB 6.2.1:
1824 * MIPS `break main; run' gave an heuristic-fence-post warning
1826 When attempting to run even a simple program, a warning about
1827 heuristic-fence-post being hit would be reported. This problem has
1830 * MIPS IRIX 'long double' crashed GDB
1832 When examining a long double variable, GDB would get a segmentation
1833 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1834 IRIX long double values).
1838 A bug in the VAX stack code was causing problems with the "next"
1839 command. This problem has been fixed.
1841 *** Changes in GDB 6.2:
1843 * Fix for ``many threads''
1845 On GNU/Linux systems that use the NPTL threads library, a program
1846 rapidly creating and deleting threads would confuse GDB leading to the
1849 ptrace: No such process.
1850 thread_db_get_info: cannot get thread info: generic error
1852 This problem has been fixed.
1854 * "-async" and "-noasync" options removed.
1856 Support for the broken "-noasync" option has been removed (it caused
1859 * New ``start'' command.
1861 This command runs the program until the begining of the main procedure.
1863 * New BSD Kernel Data Access Library (libkvm) interface
1865 Using ``target kvm'' it is now possible to debug kernel core dumps and
1866 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1867 platforms. Currently supported (native-only) configurations are:
1869 FreeBSD/amd64 x86_64-*-freebsd*
1870 FreeBSD/i386 i?86-*-freebsd*
1871 NetBSD/i386 i?86-*-netbsd*
1872 NetBSD/m68k m68*-*-netbsd*
1873 NetBSD/sparc sparc-*-netbsd*
1874 OpenBSD/amd64 x86_64-*-openbsd*
1875 OpenBSD/i386 i?86-*-openbsd*
1876 OpenBSD/m68k m68*-openbsd*
1877 OpenBSD/sparc sparc-*-openbsd*
1879 * Signal trampoline code overhauled
1881 Many generic problems with GDB's signal handling code have been fixed.
1882 These include: backtraces through non-contiguous stacks; recognition
1883 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1884 call; backtrace through a signal trampoline; step into and out of
1885 signal handlers; and single-stepping in the signal trampoline.
1887 Please note that kernel bugs are a limiting factor here. These
1888 features have been shown to work on an s390 GNU/Linux system that
1889 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1891 * Cygwin support for DWARF 2 added.
1893 * New native configurations
1895 GNU/Linux/hppa hppa*-*-linux*
1896 OpenBSD/hppa hppa*-*-openbsd*
1897 OpenBSD/m68k m68*-*-openbsd*
1898 OpenBSD/m88k m88*-*-openbsd*
1899 OpenBSD/powerpc powerpc-*-openbsd*
1900 NetBSD/vax vax-*-netbsd*
1901 OpenBSD/vax vax-*-openbsd*
1903 * END-OF-LIFE frame compatibility module
1905 GDB's internal frame infrastructure has been completely rewritten.
1906 The new infrastructure making it possible to support key new features
1907 including DWARF 2 Call Frame Information. To aid in the task of
1908 migrating old configurations to this new infrastructure, a
1909 compatibility module, that allowed old configurations to continue to
1910 work, was also included.
1912 GDB 6.2 will be the last release to include this frame compatibility
1913 module. This change directly impacts the following configurations:
1923 Unless there is activity to revive these configurations, they will be
1924 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1926 * REMOVED configurations and files
1928 Sun 3, running SunOS 3 m68*-*-sunos3*
1929 Sun 3, running SunOS 4 m68*-*-sunos4*
1930 Sun 2, running SunOS 3 m68000-*-sunos3*
1931 Sun 2, running SunOS 4 m68000-*-sunos4*
1932 Motorola 680x0 running LynxOS m68*-*-lynxos*
1933 AT&T 3b1/Unix pc m68*-att-*
1934 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1935 decstation mips-dec-* mips-little-*
1936 riscos mips-*-riscos* mips-*-sysv*
1937 sonymips mips-sony-*
1938 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1940 *** Changes in GDB 6.1.1:
1942 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1944 The TUI (Text-mode User Interface) is now built as part of a default
1945 GDB configuration. It is enabled by either selecting the TUI with the
1946 command line option "-i=tui" or by running the separate "gdbtui"
1947 program. For more information on the TUI, see the manual "Debugging
1950 * Pending breakpoint support (also included in GDB 6.1)
1952 Support has been added to allow you to specify breakpoints in shared
1953 libraries that have not yet been loaded. If a breakpoint location
1954 cannot be found, and the "breakpoint pending" option is set to auto,
1955 GDB queries you if you wish to make the breakpoint pending on a future
1956 shared-library load. If and when GDB resolves the breakpoint symbol,
1957 the pending breakpoint is removed as one or more regular breakpoints
1960 Pending breakpoints are very useful for GCJ Java debugging.
1962 * Fixed ISO-C build problems
1964 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1965 non ISO-C code that stopped them being built using a more strict ISO-C
1966 compiler (e.g., IBM's C compiler).
1968 * Fixed build problem on IRIX 5
1970 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1971 wasn't able to compile compile on an IRIX 5 system.
1973 * Added execute permission to gdb/gdbserver/configure
1975 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1976 permission. This bug would cause configure to fail on a number of
1977 systems (Solaris, IRIX). Ref: server/519.
1979 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1981 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1982 has been updated to use constant array sizes.
1984 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1986 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1987 its generated DWARF Call Frame Info. This encoding was causing GDB to
1988 panic, that panic has been fixed. Ref: gdb/1628.
1990 * Fixed a problem when examining parameters in shared library code.
1992 When examining parameters in optimized shared library code generated
1993 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1994 not available''. GDB now correctly displays the variable's value.
1996 *** Changes in GDB 6.1:
1998 * Removed --with-mmalloc
2000 Support for the mmalloc memory manager has been removed, as it
2001 conflicted with the internal gdb byte cache.
2003 * Changes in AMD64 configurations
2005 The AMD64 target now includes the %cs and %ss registers. As a result
2006 the AMD64 remote protocol has changed; this affects the floating-point
2007 and SSE registers. If you rely on those registers for your debugging,
2008 you should upgrade gdbserver on the remote side.
2010 * Revised SPARC target
2012 The SPARC target has been completely revised, incorporating the
2013 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2014 support for LynxOS and SunOS 4 has been dropped. Calling functions
2015 from within GDB on operating systems with a non-executable stack
2016 (Solaris, OpenBSD) now works.
2020 GDB has a new C++ demangler which does a better job on the mangled
2021 names generated by current versions of g++. It also runs faster, so
2022 with this and other changes gdb should now start faster on large C++
2025 * DWARF 2 Location Expressions
2027 GDB support for location expressions has been extended to support function
2028 arguments and frame bases. Older versions of GDB could crash when they
2031 * C++ nested types and namespaces
2033 GDB's support for nested types and namespaces in C++ has been
2034 improved, especially if you use the DWARF 2 debugging format. (This
2035 is the default for recent versions of GCC on most platforms.)
2036 Specifically, if you have a class "Inner" defined within a class or
2037 namespace "Outer", then GDB realizes that the class's name is
2038 "Outer::Inner", not simply "Inner". This should greatly reduce the
2039 frequency of complaints about not finding RTTI symbols. In addition,
2040 if you are stopped at inside of a function defined within a namespace,
2041 GDB modifies its name lookup accordingly.
2043 * New native configurations
2045 NetBSD/amd64 x86_64-*-netbsd*
2046 OpenBSD/amd64 x86_64-*-openbsd*
2047 OpenBSD/alpha alpha*-*-openbsd*
2048 OpenBSD/sparc sparc-*-openbsd*
2049 OpenBSD/sparc64 sparc64-*-openbsd*
2051 * New debugging protocols
2053 M32R with SDI protocol m32r-*-elf*
2055 * "set prompt-escape-char" command deleted.
2057 The command "set prompt-escape-char" has been deleted. This command,
2058 and its very obscure effet on GDB's prompt, was never documented,
2059 tested, nor mentioned in the NEWS file.
2061 * OBSOLETE configurations and files
2063 Configurations that have been declared obsolete in this release have
2064 been commented out. Unless there is activity to revive these
2065 configurations, the next release of GDB will have their sources
2066 permanently REMOVED.
2068 Sun 3, running SunOS 3 m68*-*-sunos3*
2069 Sun 3, running SunOS 4 m68*-*-sunos4*
2070 Sun 2, running SunOS 3 m68000-*-sunos3*
2071 Sun 2, running SunOS 4 m68000-*-sunos4*
2072 Motorola 680x0 running LynxOS m68*-*-lynxos*
2073 AT&T 3b1/Unix pc m68*-att-*
2074 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2075 decstation mips-dec-* mips-little-*
2076 riscos mips-*-riscos* mips-*-sysv*
2077 sonymips mips-sony-*
2078 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2080 * REMOVED configurations and files
2082 SGI Irix-4.x mips-sgi-irix4 or iris4
2083 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2084 Z8000 simulator z8k-zilog-none or z8ksim
2085 Matsushita MN10200 w/simulator mn10200-*-*
2086 H8/500 simulator h8500-hitachi-hms or h8500hms
2087 HP/PA running BSD hppa*-*-bsd*
2088 HP/PA running OSF/1 hppa*-*-osf*
2089 HP/PA Pro target hppa*-*-pro*
2090 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2091 386BSD i[3456]86-*-bsd*
2092 Sequent family i[3456]86-sequent-sysv4*
2093 i[3456]86-sequent-sysv*
2094 i[3456]86-sequent-bsd*
2095 SPARC running LynxOS sparc-*-lynxos*
2096 SPARC running SunOS 4 sparc-*-sunos4*
2097 Tsqware Sparclet sparclet-*-*
2098 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2100 *** Changes in GDB 6.0:
2104 Support for debugging the Objective-C programming language has been
2105 integrated into GDB.
2107 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2109 DWARF 2's Call Frame Information makes available compiler generated
2110 information that more exactly describes the program's run-time stack.
2111 By using this information, GDB is able to provide more robust stack
2114 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2115 have been updated to use a new backtrace mechanism which includes
2116 DWARF 2 CFI support.
2120 GDB's remote protocol has been extended to include support for hosted
2121 file I/O (where the remote target uses GDB's file system). See GDB's
2122 remote protocol documentation for details.
2124 * All targets using the new architecture framework.
2126 All of GDB's targets have been updated to use the new internal
2127 architecture framework. The way is now open for future GDB releases
2128 to include cross-architecture native debugging support (i386 on amd64,
2131 * GNU/Linux's Thread Local Storage (TLS)
2133 GDB now includes support for for the GNU/Linux implementation of
2134 per-thread variables.
2136 * GNU/Linux's Native POSIX Thread Library (NPTL)
2138 GDB's thread code has been updated to work with either the new
2139 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2141 * Separate debug info.
2143 GDB, in conjunction with BINUTILS, now supports a mechanism for
2144 automatically loading debug information from a separate file. Instead
2145 of shipping full debug and non-debug versions of system libraries,
2146 system integrators can now instead ship just the stripped libraries
2147 and optional debug files.
2149 * DWARF 2 Location Expressions
2151 DWARF 2 Location Expressions allow the compiler to more completely
2152 describe the location of variables (even in optimized code) to the
2155 GDB now includes preliminary support for location expressions (support
2156 for DW_OP_piece is still missing).
2160 A number of long standing bugs that caused GDB to die while starting a
2161 Java application have been fixed. GDB's Java support is now
2162 considered "useable".
2164 * GNU/Linux support for fork, vfork, and exec.
2166 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2167 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2170 * GDB supports logging output to a file
2172 There are two new commands, "set logging" and "show logging", which can be
2173 used to capture GDB's output to a file.
2175 * The meaning of "detach" has changed for gdbserver
2177 The "detach" command will now resume the application, as documented. To
2178 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2181 * d10v, m68hc11 `regs' command deprecated
2183 The `info registers' command has been updated so that it displays the
2184 registers using a format identical to the old `regs' command.
2188 A new command, "maint set profile on/off", has been added. This command can
2189 be used to enable or disable profiling while running GDB, to profile a
2190 session or a set of commands. In addition there is a new configure switch,
2191 "--enable-profiling", which will cause GDB to be compiled with profiling
2192 data, for more informative profiling results.
2194 * Default MI syntax changed to "mi2".
2196 The default MI (machine interface) syntax, enabled by the command line
2197 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2198 "mi1", can be enabled by specifying the option "-i=mi1".
2200 Support for the original "mi0" syntax (included in GDB 5.0) has been
2203 Fix for gdb/192: removed extraneous space when displaying frame level.
2204 Fix for gdb/672: update changelist is now output in mi list format.
2205 Fix for gdb/702: a -var-assign that updates the value now shows up
2206 in a subsequent -var-update.
2208 * New native configurations.
2210 FreeBSD/amd64 x86_64-*-freebsd*
2212 * Multi-arched targets.
2214 HP/PA HPUX11 hppa*-*-hpux*
2215 Renesas M32R/D w/simulator m32r-*-elf*
2217 * OBSOLETE configurations and files
2219 Configurations that have been declared obsolete in this release have
2220 been commented out. Unless there is activity to revive these
2221 configurations, the next release of GDB will have their sources
2222 permanently REMOVED.
2224 Z8000 simulator z8k-zilog-none or z8ksim
2225 Matsushita MN10200 w/simulator mn10200-*-*
2226 H8/500 simulator h8500-hitachi-hms or h8500hms
2227 HP/PA running BSD hppa*-*-bsd*
2228 HP/PA running OSF/1 hppa*-*-osf*
2229 HP/PA Pro target hppa*-*-pro*
2230 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2231 Sequent family i[3456]86-sequent-sysv4*
2232 i[3456]86-sequent-sysv*
2233 i[3456]86-sequent-bsd*
2234 Tsqware Sparclet sparclet-*-*
2235 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2237 * REMOVED configurations and files
2240 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2241 IBM AIX PS/2 i[3456]86-*-aix
2242 i386 running Mach 3.0 i[3456]86-*-mach3*
2243 i386 running Mach i[3456]86-*-mach*
2244 i386 running OSF/1 i[3456]86-*osf1mk*
2245 HP/Apollo 68k Family m68*-apollo*-sysv*,
2247 m68*-hp-bsd*, m68*-hp-hpux*
2248 Argonaut Risc Chip (ARC) arc-*-*
2249 Mitsubishi D30V d30v-*-*
2250 Fujitsu FR30 fr30-*-elf*
2251 OS/9000 i[34]86-*-os9k
2252 I960 with MON960 i960-*-coff
2254 * MIPS $fp behavior changed
2256 The convenience variable $fp, for the MIPS, now consistently returns
2257 the address of the current frame's base. Previously, depending on the
2258 context, $fp could refer to either $sp or the current frame's base
2259 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2260 The GNU Source-Level Debugger''.
2262 *** Changes in GDB 5.3:
2264 * GNU/Linux shared library multi-threaded performance improved.
2266 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2267 `/proc', in preference to `ptrace' for memory reads. This may result
2268 in an improvement in the start-up time of multi-threaded, shared
2269 library applications when run under GDB. One GDB user writes: ``loads
2270 shared libs like mad''.
2272 * ``gdbserver'' now supports multi-threaded applications on some targets
2274 Support for debugging multi-threaded applications which use
2275 the GNU/Linux LinuxThreads package has been added for
2276 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2277 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2279 * GDB now supports C/C++ preprocessor macros.
2281 GDB now expands preprocessor macro invocations in C/C++ expressions,
2282 and provides various commands for showing macro definitions and how
2285 The new command `macro expand EXPRESSION' expands any macro
2286 invocations in expression, and shows the result.
2288 The new command `show macro MACRO-NAME' shows the definition of the
2289 macro named MACRO-NAME, and where it was defined.
2291 Most compilers don't include information about macros in the debugging
2292 information by default. In GCC 3.1, for example, you need to compile
2293 your program with the options `-gdwarf-2 -g3'. If the macro
2294 information is present in the executable, GDB will read it.
2296 * Multi-arched targets.
2298 DEC Alpha (partial) alpha*-*-*
2299 DEC VAX (partial) vax-*-*
2301 National Semiconductor NS32000 (partial) ns32k-*-*
2302 Motorola 68000 (partial) m68k-*-*
2303 Motorola MCORE mcore-*-*
2307 Fujitsu FRV architecture added by Red Hat frv*-*-*
2310 * New native configurations
2312 Alpha NetBSD alpha*-*-netbsd*
2313 SH NetBSD sh*-*-netbsdelf*
2314 MIPS NetBSD mips*-*-netbsd*
2315 UltraSPARC NetBSD sparc64-*-netbsd*
2317 * OBSOLETE configurations and files
2319 Configurations that have been declared obsolete in this release have
2320 been commented out. Unless there is activity to revive these
2321 configurations, the next release of GDB will have their sources
2322 permanently REMOVED.
2324 Mitsubishi D30V d30v-*-*
2325 OS/9000 i[34]86-*-os9k
2326 IBM AIX PS/2 i[3456]86-*-aix
2327 Fujitsu FR30 fr30-*-elf*
2328 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2329 Argonaut Risc Chip (ARC) arc-*-*
2330 i386 running Mach 3.0 i[3456]86-*-mach3*
2331 i386 running Mach i[3456]86-*-mach*
2332 i386 running OSF/1 i[3456]86-*osf1mk*
2333 HP/Apollo 68k Family m68*-apollo*-sysv*,
2335 m68*-hp-bsd*, m68*-hp-hpux*
2336 I960 with MON960 i960-*-coff
2338 * OBSOLETE languages
2340 CHILL, a Pascal like language used by telecommunications companies.
2342 * REMOVED configurations and files
2344 AMD 29k family via UDI a29k-amd-udi, udi29k
2345 A29K VxWorks a29k-*-vxworks
2346 AMD 29000 embedded, using EBMON a29k-none-none
2347 AMD 29000 embedded with COFF a29k-none-coff
2348 AMD 29000 embedded with a.out a29k-none-aout
2350 testsuite/gdb.hp/gdb.threads-hp/ directory
2352 * New command "set max-user-call-depth <nnn>"
2354 This command allows the user to limit the call depth of user-defined
2355 commands. The default is 1024.
2357 * Changes in FreeBSD/i386 native debugging.
2359 Support for the "generate-core-file" has been added.
2361 * New commands "dump", "append", and "restore".
2363 These commands allow data to be copied from target memory
2364 to a bfd-format or binary file (dump and append), and back
2365 from a file into memory (restore).
2367 * Improved "next/step" support on multi-processor Alpha Tru64.
2369 The previous single-step mechanism could cause unpredictable problems,
2370 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2371 of a software single-step mechanism prevents this.
2373 *** Changes in GDB 5.2.1:
2381 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2382 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2383 Fix, by Joel Brobecker imported from mainline.
2385 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2386 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2387 Fix, by Fred Fish, imported from mainline.
2389 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2390 Surprisingly enough, it works now.
2391 By Michal Ludvig, imported from mainline.
2393 i386 hardware watchpoint support:
2394 avoid misses on second run for some targets.
2395 By Pierre Muller, imported from mainline.
2397 *** Changes in GDB 5.2:
2399 * New command "set trust-readonly-sections on[off]".
2401 This command is a hint that tells gdb that read-only sections
2402 really are read-only (ie. that their contents will not change).
2403 In this mode, gdb will go to the object file rather than the
2404 target to read memory from read-only sections (such as ".text").
2405 This can be a significant performance improvement on some
2406 (notably embedded) targets.
2408 * New command "generate-core-file" (or "gcore").
2410 This new gdb command allows the user to drop a core file of the child
2411 process state at any time. So far it's been implemented only for
2412 GNU/Linux and Solaris, but should be relatively easily ported to other
2413 hosts. Argument is core file name (defaults to core.<pid>).
2415 * New command line option
2417 GDB now accepts --pid or -p followed by a process id.
2419 * Change in command line behavior -- corefiles vs. process ids.
2421 There is a subtle behavior in the way in which GDB handles
2422 command line arguments. The first non-flag argument is always
2423 a program to debug, but the second non-flag argument may either
2424 be a corefile or a process id. Previously, GDB would attempt to
2425 open the second argument as a corefile, and if that failed, would
2426 issue a superfluous error message and then attempt to attach it as
2427 a process. Now, if the second argument begins with a non-digit,
2428 it will be treated as a corefile. If it begins with a digit,
2429 GDB will attempt to attach it as a process, and if no such process
2430 is found, will then attempt to open it as a corefile.
2432 * Changes in ARM configurations.
2434 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2435 configuration is fully multi-arch.
2437 * New native configurations
2439 ARM NetBSD arm*-*-netbsd*
2440 x86 OpenBSD i[3456]86-*-openbsd*
2441 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2442 Sparc64 running FreeBSD sparc64-*-freebsd*
2446 Sanyo XStormy16 xstormy16-elf
2448 * OBSOLETE configurations and files
2450 Configurations that have been declared obsolete in this release have
2451 been commented out. Unless there is activity to revive these
2452 configurations, the next release of GDB will have their sources
2453 permanently REMOVED.
2455 AMD 29k family via UDI a29k-amd-udi, udi29k
2456 A29K VxWorks a29k-*-vxworks
2457 AMD 29000 embedded, using EBMON a29k-none-none
2458 AMD 29000 embedded with COFF a29k-none-coff
2459 AMD 29000 embedded with a.out a29k-none-aout
2461 testsuite/gdb.hp/gdb.threads-hp/ directory
2463 * REMOVED configurations and files
2465 TI TMS320C80 tic80-*-*
2467 PowerPC Solaris powerpcle-*-solaris*
2468 PowerPC Windows NT powerpcle-*-cygwin32
2469 PowerPC Netware powerpc-*-netware*
2470 Harris/CXUX m88k m88*-harris-cxux*
2471 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2472 ns32k-utek-sysv* ns32k-utek-*
2473 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2474 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2475 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2476 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2477 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2479 * Changes to command line processing
2481 The new `--args' feature can be used to specify command-line arguments
2482 for the inferior from gdb's command line.
2484 * Changes to key bindings
2486 There is a new `operate-and-get-next' function bound to `C-o'.
2488 *** Changes in GDB 5.1.1
2490 Fix compile problem on DJGPP.
2492 Fix a problem with floating-point registers on the i386 being
2495 Fix to stop GDB crashing on .debug_str debug info.
2497 Numerous documentation fixes.
2499 Numerous testsuite fixes.
2501 *** Changes in GDB 5.1:
2503 * New native configurations
2505 Alpha FreeBSD alpha*-*-freebsd*
2506 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2507 MIPS GNU/Linux mips*-*-linux*
2508 MIPS SGI Irix 6.x mips*-sgi-irix6*
2509 ia64 AIX ia64-*-aix*
2510 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2514 Motorola 68HC11 and 68HC12 m68hc11-elf
2516 UltraSparc running GNU/Linux sparc64-*-linux*
2518 * OBSOLETE configurations and files
2520 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2521 Harris/CXUX m88k m88*-harris-cxux*
2522 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2523 ns32k-utek-sysv* ns32k-utek-*
2524 TI TMS320C80 tic80-*-*
2526 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2527 PowerPC Solaris powerpcle-*-solaris*
2528 PowerPC Windows NT powerpcle-*-cygwin32
2529 PowerPC Netware powerpc-*-netware*
2530 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2531 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2532 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2533 Apple Macintosh (MPW) host N/A
2535 stuff.c (Program to stuff files into a specially prepared space in kdb)
2536 kdb-start.c (Main loop for the standalone kernel debugger)
2538 Configurations that have been declared obsolete in this release have
2539 been commented out. Unless there is activity to revive these
2540 configurations, the next release of GDB will have their sources
2541 permanently REMOVED.
2543 * REMOVED configurations and files
2545 Altos 3068 m68*-altos-*
2546 Convex c1-*-*, c2-*-*
2548 ARM RISCix arm-*-* (as host)
2552 * GDB has been converted to ISO C.
2554 GDB's source code has been converted to ISO C. In particular, the
2555 sources are fully protoized, and rely on standard headers being
2560 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2562 * The MI enabled by default.
2564 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2565 revised and enabled by default. Packages which use GDB as a debugging
2566 engine behind a UI or another front end are encouraged to switch to
2567 using the GDB/MI interface, instead of the old annotations interface
2568 which is now deprecated.
2570 * Support for debugging Pascal programs.
2572 GDB now includes support for debugging Pascal programs. The following
2573 main features are supported:
2575 - Pascal-specific data types such as sets;
2577 - automatic recognition of Pascal sources based on file-name
2580 - Pascal-style display of data types, variables, and functions;
2582 - a Pascal expression parser.
2584 However, some important features are not yet supported.
2586 - Pascal string operations are not supported at all;
2588 - there are some problems with boolean types;
2590 - Pascal type hexadecimal constants are not supported
2591 because they conflict with the internal variables format;
2593 - support for Pascal objects and classes is not full yet;
2595 - unlike Pascal, GDB is case-sensitive for symbol names.
2597 * Changes in completion.
2599 Commands such as `shell', `run' and `set args', which pass arguments
2600 to inferior programs, now complete on file names, similar to what
2601 users expect at the shell prompt.
2603 Commands which accept locations, such as `disassemble', `print',
2604 `breakpoint', `until', etc. now complete on filenames as well as
2605 program symbols. Thus, if you type "break foob TAB", and the source
2606 files linked into the programs include `foobar.c', that file name will
2607 be one of the candidates for completion. However, file names are not
2608 considered for completion after you typed a colon that delimits a file
2609 name from a name of a function in that file, as in "break foo.c:bar".
2611 `set demangle-style' completes on available demangling styles.
2613 * New platform-independent commands:
2615 It is now possible to define a post-hook for a command as well as a
2616 hook that runs before the command. For more details, see the
2617 documentation of `hookpost' in the GDB manual.
2619 * Changes in GNU/Linux native debugging.
2621 Support for debugging multi-threaded programs has been completely
2622 revised for all platforms except m68k and sparc. You can now debug as
2623 many threads as your system allows you to have.
2625 Attach/detach is supported for multi-threaded programs.
2627 Support for SSE registers was added for x86. This doesn't work for
2628 multi-threaded programs though.
2630 * Changes in MIPS configurations.
2632 Multi-arch support is enabled for all MIPS configurations.
2634 GDB can now be built as native debugger on SGI Irix 6.x systems for
2635 debugging n32 executables. (Debugging 64-bit executables is not yet
2638 * Unified support for hardware watchpoints in all x86 configurations.
2640 Most (if not all) native x86 configurations support hardware-assisted
2641 breakpoints and watchpoints in a unified manner. This support
2642 implements debug register sharing between watchpoints, which allows to
2643 put a virtually infinite number of watchpoints on the same address,
2644 and also supports watching regions up to 16 bytes with several debug
2647 The new maintenance command `maintenance show-debug-regs' toggles
2648 debugging print-outs in functions that insert, remove, and test
2649 watchpoints and hardware breakpoints.
2651 * Changes in the DJGPP native configuration.
2653 New command ``info dos sysinfo'' displays assorted information about
2654 the CPU, OS, memory, and DPMI server.
2656 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2657 display information about segment descriptors stored in GDT, LDT, and
2660 New commands ``info dos pde'' and ``info dos pte'' display entries
2661 from Page Directory and Page Tables (for now works with CWSDPMI only).
2662 New command ``info dos address-pte'' displays the Page Table entry for
2663 a given linear address.
2665 GDB can now pass command lines longer than 126 characters to the
2666 program being debugged (requires an update to the libdbg.a library
2667 which is part of the DJGPP development kit).
2669 DWARF2 debug info is now supported.
2671 It is now possible to `step' and `next' through calls to `longjmp'.
2673 * Changes in documentation.
2675 All GDB documentation was converted to GFDL, the GNU Free
2676 Documentation License.
2678 Tracepoints-related commands are now fully documented in the GDB
2681 TUI, the Text-mode User Interface, is now documented in the manual.
2683 Tracepoints-related commands are now fully documented in the GDB
2686 The "GDB Internals" manual now has an index. It also includes
2687 documentation of `ui_out' functions, GDB coding standards, x86
2688 hardware watchpoints, and memory region attributes.
2690 * GDB's version number moved to ``version.in''
2692 The Makefile variable VERSION has been replaced by the file
2693 ``version.in''. People creating GDB distributions should update the
2694 contents of this file.
2698 GUD support is now a standard part of the EMACS distribution.
2700 *** Changes in GDB 5.0:
2702 * Improved support for debugging FP programs on x86 targets
2704 Unified and much-improved support for debugging floating-point
2705 programs on all x86 targets. In particular, ``info float'' now
2706 displays the FP registers in the same format on all x86 targets, with
2707 greater level of detail.
2709 * Improvements and bugfixes in hardware-assisted watchpoints
2711 It is now possible to watch array elements, struct members, and
2712 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2713 on x86 targets no longer erroneously trigger when the address is
2716 * Improvements in the native DJGPP version of GDB
2718 The distribution now includes all the scripts and auxiliary files
2719 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2720 machines ``out of the box''.
2722 The DJGPP version can now debug programs that use signals. It is
2723 possible to catch signals that happened in the debuggee, deliver
2724 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2725 would kill the program being debugged.) Programs that hook hardware
2726 interrupts (keyboard, timer, etc.) can also be debugged.
2728 It is now possible to debug DJGPP programs that redirect their
2729 standard handles or switch them to raw (as opposed to cooked) mode, or
2730 even close them. The command ``run < foo > bar'' works as expected,
2731 and ``info terminal'' reports useful information about the debuggee's
2732 terminal, including raw/cooked mode, redirection, etc.
2734 The DJGPP version now uses termios functions for console I/O, which
2735 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2738 DOS-style file names with drive letters are now fully supported by
2741 It is now possible to debug DJGPP programs that switch their working
2742 directory. It is also possible to rerun the debuggee any number of
2743 times without restarting GDB; thus, you can use the same setup,
2744 breakpoints, etc. for many debugging sessions.
2746 * New native configurations
2748 ARM GNU/Linux arm*-*-linux*
2749 PowerPC GNU/Linux powerpc-*-linux*
2753 Motorola MCore mcore-*-*
2754 x86 VxWorks i[3456]86-*-vxworks*
2755 PowerPC VxWorks powerpc-*-vxworks*
2756 TI TMS320C80 tic80-*-*
2758 * OBSOLETE configurations
2760 Altos 3068 m68*-altos-*
2761 Convex c1-*-*, c2-*-*
2763 ARM RISCix arm-*-* (as host)
2766 Configurations that have been declared obsolete will be commented out,
2767 but the code will be left in place. If there is no activity to revive
2768 these configurations before the next release of GDB, the sources will
2769 be permanently REMOVED.
2771 * Gould support removed
2773 Support for the Gould PowerNode and NP1 has been removed.
2775 * New features for SVR4
2777 On SVR4 native platforms (such as Solaris), if you attach to a process
2778 without first loading a symbol file, GDB will now attempt to locate and
2779 load symbols from the running process's executable file.
2781 * Many C++ enhancements
2783 C++ support has been greatly improved. Overload resolution now works properly
2784 in almost all cases. RTTI support is on the way.
2786 * Remote targets can connect to a sub-program
2788 A popen(3) style serial-device has been added. This device starts a
2789 sub-process (such as a stand-alone simulator) and then communicates
2790 with that. The sub-program to run is specified using the syntax
2791 ``|<program> <args>'' vis:
2793 (gdb) set remotedebug 1
2794 (gdb) target extended-remote |mn10300-elf-sim program-args
2796 * MIPS 64 remote protocol
2798 A long standing bug in the mips64 remote protocol where by GDB
2799 expected certain 32 bit registers (ex SR) to be transfered as 32
2800 instead of 64 bits has been fixed.
2802 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2803 added to provide backward compatibility with older versions of GDB.
2805 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2807 The command ``set remotebinarydownload'' command has been replaced by
2808 ``set remote X-packet''. Other commands in ``set remote'' family
2809 include ``set remote P-packet''.
2811 * Breakpoint commands accept ranges.
2813 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2814 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2815 ``tracepoint passcount'' also accepts a range of tracepoints.
2817 * ``apropos'' command added.
2819 The ``apropos'' command searches through command names and
2820 documentation strings, printing out matches, making it much easier to
2821 try to find a command that does what you are looking for.
2825 A new machine oriented interface (MI) has been added to GDB. This
2826 interface is designed for debug environments running GDB as a separate
2827 process. This is part of the long term libGDB project. See the
2828 "GDB/MI" chapter of the GDB manual for further information. It can be
2829 enabled by configuring with:
2831 .../configure --enable-gdbmi
2833 *** Changes in GDB-4.18:
2835 * New native configurations
2837 HP-UX 10.20 hppa*-*-hpux10.20
2838 HP-UX 11.x hppa*-*-hpux11.0*
2839 M68K GNU/Linux m68*-*-linux*
2843 Fujitsu FR30 fr30-*-elf*
2844 Intel StrongARM strongarm-*-*
2845 Mitsubishi D30V d30v-*-*
2847 * OBSOLETE configurations
2849 Gould PowerNode, NP1 np1-*-*, pn-*-*
2851 Configurations that have been declared obsolete will be commented out,
2852 but the code will be left in place. If there is no activity to revive
2853 these configurations before the next release of GDB, the sources will
2854 be permanently REMOVED.
2858 As a compatibility experiment, GDB's source files buildsym.h and
2859 buildsym.c have been converted to pure standard C, no longer
2860 containing any K&R compatibility code. We believe that all systems in
2861 use today either come with a standard C compiler, or have a GCC port
2862 available. If this is not true, please report the affected
2863 configuration to bug-gdb@gnu.org immediately. See the README file for
2864 information about getting a standard C compiler if you don't have one
2869 GDB now uses readline 2.2.
2871 * set extension-language
2873 You can now control the mapping between filename extensions and source
2874 languages by using the `set extension-language' command. For instance,
2875 you can ask GDB to treat .c files as C++ by saying
2876 set extension-language .c c++
2877 The command `info extensions' lists all of the recognized extensions
2878 and their associated languages.
2880 * Setting processor type for PowerPC and RS/6000
2882 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2883 you can use the `set processor' command to specify what variant of the
2884 PowerPC family you are debugging. The command
2888 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2889 following PowerPC and RS6000 variants:
2891 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2892 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2894 403GC IBM PowerPC 403GC
2895 505 Motorola PowerPC 505
2896 860 Motorola PowerPC 860 or 850
2897 601 Motorola PowerPC 601
2898 602 Motorola PowerPC 602
2899 603 Motorola/IBM PowerPC 603 or 603e
2900 604 Motorola PowerPC 604 or 604e
2901 750 Motorola/IBM PowerPC 750 or 750
2903 At the moment, this command just tells GDB what to name the
2904 special-purpose processor registers. Since almost all the affected
2905 registers are inaccessible to user-level programs, this command is
2906 only useful for remote debugging in its present form.
2910 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2911 more extensive support for HP-UX. Added features include shared
2912 library support, kernel threads and hardware watchpoints for 11.00,
2913 support for HP's ANSI C and C++ compilers, and a compatibility mode
2914 for xdb and dbx commands.
2918 HP's donation includes the new concept of catchpoints, which is a
2919 generalization of the old catch command. On HP-UX, it is now possible
2920 to catch exec, fork, and vfork, as well as library loading.
2922 This means that the existing catch command has changed; its first
2923 argument now specifies the type of catch to be set up. See the
2924 output of "help catch" for a list of catchpoint types.
2926 * Debugging across forks
2928 On HP-UX, you can choose which process to debug when a fork() happens
2933 HP has donated a curses-based terminal user interface (TUI). To get
2934 it, build with --enable-tui. Although this can be enabled for any
2935 configuration, at present it only works for native HP debugging.
2937 * GDB remote protocol additions
2939 A new protocol packet 'X' that writes binary data is now available.
2940 Default behavior is to try 'X', then drop back to 'M' if the stub
2941 fails to respond. The settable variable `remotebinarydownload'
2942 allows explicit control over the use of 'X'.
2944 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2945 full 64-bit address. The command
2947 set remoteaddresssize 32
2949 can be used to revert to the old behaviour. For existing remote stubs
2950 the change should not be noticed, as the additional address information
2953 In order to assist in debugging stubs, you may use the maintenance
2954 command `packet' to send any text string to the stub. For instance,
2956 maint packet heythere
2958 sends the packet "$heythere#<checksum>". Note that it is very easy to
2959 disrupt a debugging session by sending the wrong packet at the wrong
2962 The compare-sections command allows you to compare section data on the
2963 target to what is in the executable file without uploading or
2964 downloading, by comparing CRC checksums.
2966 * Tracing can collect general expressions
2968 You may now collect general expressions at tracepoints. This requires
2969 further additions to the target-side stub; see tracepoint.c and
2970 doc/agentexpr.texi for further details.
2972 * mask-address variable for Mips
2974 For Mips targets, you may control the zeroing of the upper 32 bits of
2975 a 64-bit address by entering `set mask-address on'. This is mainly
2976 of interest to users of embedded R4xxx and R5xxx processors.
2978 * Higher serial baud rates
2980 GDB's serial code now allows you to specify baud rates 57600, 115200,
2981 230400, and 460800 baud. (Note that your host system may not be able
2982 to achieve all of these rates.)
2986 The i960 configuration now includes an initial implementation of a
2987 builtin simulator, contributed by Jim Wilson.
2990 *** Changes in GDB-4.17:
2992 * New native configurations
2994 Alpha GNU/Linux alpha*-*-linux*
2995 Unixware 2.x i[3456]86-unixware2*
2996 Irix 6.x mips*-sgi-irix6*
2997 PowerPC GNU/Linux powerpc-*-linux*
2998 PowerPC Solaris powerpcle-*-solaris*
2999 Sparc GNU/Linux sparc-*-linux*
3000 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3004 Argonaut Risc Chip (ARC) arc-*-*
3005 Hitachi H8/300S h8300*-*-*
3006 Matsushita MN10200 w/simulator mn10200-*-*
3007 Matsushita MN10300 w/simulator mn10300-*-*
3008 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3009 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3010 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3011 Mitsubishi D10V w/simulator d10v-*-*
3012 Mitsubishi M32R/D w/simulator m32r-*-elf*
3013 Tsqware Sparclet sparclet-*-*
3014 NEC V850 w/simulator v850-*-*
3016 * New debugging protocols
3018 ARM with RDI protocol arm*-*-*
3019 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3020 DDB and LSI variants of PMON protocol mips*-*-*
3021 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3022 PowerPC with SDS protocol powerpc{,le}-*-eabi
3023 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3027 All configurations can now understand and use the DWARF 2 debugging
3028 format. The choice is automatic, if the symbol file contains DWARF 2
3033 GDB now includes basic Java language support. This support is
3034 only useful with Java compilers that produce native machine code.
3036 * solib-absolute-prefix and solib-search-path
3038 For SunOS and SVR4 shared libraries, you may now set the prefix for
3039 loading absolute shared library symbol files, and the search path for
3040 locating non-absolute shared library symbol files.
3042 * Live range splitting
3044 GDB can now effectively debug code for which GCC has performed live
3045 range splitting as part of its optimization. See gdb/doc/LRS for
3046 more details on the expected format of the stabs information.
3050 GDB's support for the GNU Hurd, including thread debugging, has been
3051 updated to work with current versions of the Hurd.
3055 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3056 instruction set. ARM GDB automatically detects when Thumb
3057 instructions are in use, and adjusts disassembly and backtracing
3062 GDB's MIPS target configurations now handle the MIP16 16-bit
3067 GDB now includes support for overlays; if an executable has been
3068 linked such that multiple sections are based at the same address, GDB
3069 will decide which section to use for symbolic info. You can choose to
3070 control the decision manually, using overlay commands, or implement
3071 additional target-side support and use "overlay load-target" to bring
3072 in the overlay mapping. Do "help overlay" for more detail.
3076 The command "info symbol <address>" displays information about
3077 the symbol at the specified address.
3081 The standard remote protocol now includes an extension that allows
3082 asynchronous collection and display of trace data. This requires
3083 extensive support in the target-side debugging stub. Tracing mode
3084 includes a new interaction mode in GDB and new commands: see the
3085 file tracepoint.c for more details.
3089 Configurations for embedded MIPS now include a simulator contributed
3090 by Cygnus Solutions. The simulator supports the instruction sets
3091 of most MIPS variants.
3095 Sparc configurations may now include the ERC32 simulator contributed
3096 by the European Space Agency. The simulator is not built into
3097 Sparc targets by default; configure with --enable-sim to include it.
3101 For target configurations that may include multiple variants of a
3102 basic architecture (such as MIPS and SH), you may now set the
3103 architecture explicitly. "set arch" sets, "info arch" lists
3104 the possible architectures.
3106 *** Changes in GDB-4.16:
3108 * New native configurations
3110 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3111 M68K NetBSD m68k-*-netbsd*
3112 PowerPC AIX 4.x powerpc-*-aix*
3113 PowerPC MacOS powerpc-*-macos*
3114 PowerPC Windows NT powerpcle-*-cygwin32
3115 RS/6000 AIX 4.x rs6000-*-aix4*
3119 ARM with RDP protocol arm-*-*
3120 I960 with MON960 i960-*-coff
3121 MIPS VxWorks mips*-*-vxworks*
3122 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3123 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3125 Matra Sparclet sparclet-*-*
3129 The powerpc-eabi configuration now includes the PSIM simulator,
3130 contributed by Andrew Cagney, with assistance from Mike Meissner.
3131 PSIM is a very elaborate model of the PowerPC, including not only
3132 basic instruction set execution, but also details of execution unit
3133 performance and I/O hardware. See sim/ppc/README for more details.
3137 GDB now works with Solaris 2.5.
3139 * Windows 95/NT native
3141 GDB will now work as a native debugger on Windows 95 and Windows NT.
3142 To build it from source, you must use the "gnu-win32" environment,
3143 which uses a DLL to emulate enough of Unix to run the GNU tools.
3144 Further information, binaries, and sources are available at
3145 ftp.cygnus.com, under pub/gnu-win32.
3147 * dont-repeat command
3149 If a user-defined command includes the command `dont-repeat', then the
3150 command will not be repeated if the user just types return. This is
3151 useful if the command is time-consuming to run, so that accidental
3152 extra keystrokes don't run the same command many times.
3154 * Send break instead of ^C
3156 The standard remote protocol now includes an option to send a break
3157 rather than a ^C to the target in order to interrupt it. By default,
3158 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3160 * Remote protocol timeout
3162 The standard remote protocol includes a new variable `remotetimeout'
3163 that allows you to set the number of seconds before GDB gives up trying
3164 to read from the target. The default value is 2.
3166 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3168 By default GDB will automatically keep track of objects as they are
3169 loaded and unloaded by the dynamic linker. By using the command `set
3170 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3171 when shared library events occur, thus allowing you to set breakpoints
3172 in shared libraries which are explicitly loaded by the inferior.
3174 Note this feature does not work on hpux8. On hpux9 you must link
3175 /usr/lib/end.o into your program. This feature should work
3176 automatically on hpux10.
3178 * Irix 5.x hardware watchpoint support
3180 Irix 5 configurations now support the use of hardware watchpoints.
3182 * Mips protocol "SYN garbage limit"
3184 When debugging a Mips target using the `target mips' protocol, you
3185 may set the number of characters that GDB will ignore by setting
3186 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3187 every character. The default value is 1050.
3189 * Recording and replaying remote debug sessions
3191 If you set `remotelogfile' to the name of a file, gdb will write to it
3192 a recording of a remote debug session. This recording may then be
3193 replayed back to gdb using "gdbreplay". See gdbserver/README for
3194 details. This is useful when you have a problem with GDB while doing
3195 remote debugging; you can make a recording of the session and send it
3196 to someone else, who can then recreate the problem.
3198 * Speedups for remote debugging
3200 GDB includes speedups for downloading and stepping MIPS systems using
3201 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3202 and more efficient S-record downloading.
3204 * Memory use reductions and statistics collection
3206 GDB now uses less memory and reports statistics about memory usage.
3207 Try the `maint print statistics' command, for example.
3209 *** Changes in GDB-4.15:
3211 * Psymtabs for XCOFF
3213 The symbol reader for AIX GDB now uses partial symbol tables. This
3214 can greatly improve startup time, especially for large executables.
3216 * Remote targets use caching
3218 Remote targets now use a data cache to speed up communication with the
3219 remote side. The data cache could lead to incorrect results because
3220 it doesn't know about volatile variables, thus making it impossible to
3221 debug targets which use memory mapped I/O devices. `set remotecache
3222 off' turns the the data cache off.
3224 * Remote targets may have threads
3226 The standard remote protocol now includes support for multiple threads
3227 in the target system, using new protocol commands 'H' and 'T'. See
3228 gdb/remote.c for details.
3232 If GDB is configured with `--enable-netrom', then it will include
3233 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3234 acts as though it is a bank of ROM on the target board, but you can
3235 write into it over the network. GDB's support consists only of
3236 support for fast loading into the emulated ROM; to debug, you must use
3237 another protocol, such as standard remote protocol. The usual
3238 sequence is something like
3240 target nrom <netrom-hostname>
3242 target remote <netrom-hostname>:1235
3246 GDB now includes support for the Apple Macintosh, as a host only. It
3247 may be run as either an MPW tool or as a standalone application, and
3248 it can debug through the serial port. All the usual GDB commands are
3249 available, but to the target command, you must supply "serial" as the
3250 device type instead of "/dev/ttyXX". See mpw-README in the main
3251 directory for more information on how to build. The MPW configuration
3252 scripts */mpw-config.in support only a few targets, and only the
3253 mips-idt-ecoff target has been tested.
3257 GDB configuration now uses autoconf. This is not user-visible,
3258 but does simplify configuration and building.
3262 GDB now supports hpux10.
3264 *** Changes in GDB-4.14:
3266 * New native configurations
3268 x86 FreeBSD i[345]86-*-freebsd
3269 x86 NetBSD i[345]86-*-netbsd
3270 NS32k NetBSD ns32k-*-netbsd
3271 Sparc NetBSD sparc-*-netbsd
3275 A29K VxWorks a29k-*-vxworks
3276 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3277 CPU32 EST-300 emulator m68*-*-est*
3278 PowerPC ELF powerpc-*-elf
3281 * Alpha OSF/1 support for procfs
3283 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3284 possible to attach to running processes. As the mounting of the /proc
3285 filesystem is optional on the Alpha, GDB automatically determines
3286 the availability of /proc during startup. This can lead to problems
3287 if /proc is unmounted after GDB has been started.
3289 * Arguments to user-defined commands
3291 User commands may accept up to 10 arguments separated by whitespace.
3292 Arguments are accessed within the user command via $arg0..$arg9. A
3295 print $arg0 + $arg1 + $arg2
3297 To execute the command use:
3300 Defines the command "adder" which prints the sum of its three arguments.
3301 Note the arguments are text substitutions, so they may reference variables,
3302 use complex expressions, or even perform inferior function calls.
3304 * New `if' and `while' commands
3306 This makes it possible to write more sophisticated user-defined
3307 commands. Both commands take a single argument, which is the
3308 expression to evaluate, and must be followed by the commands to
3309 execute, one per line, if the expression is nonzero, the list being
3310 terminated by the word `end'. The `if' command list may include an
3311 `else' word, which causes the following commands to be executed only
3312 if the expression is zero.
3314 * Fortran source language mode
3316 GDB now includes partial support for Fortran 77. It will recognize
3317 Fortran programs and can evaluate a subset of Fortran expressions, but
3318 variables and functions may not be handled correctly. GDB will work
3319 with G77, but does not yet know much about symbols emitted by other
3322 * Better HPUX support
3324 Most debugging facilities now work on dynamic executables for HPPAs
3325 running hpux9 or later. You can attach to running dynamically linked
3326 processes, but by default the dynamic libraries will be read-only, so
3327 for instance you won't be able to put breakpoints in them. To change
3328 that behavior do the following before running the program:
3334 This will cause the libraries to be mapped private and read-write.
3335 To revert to the normal behavior, do this:
3341 You cannot set breakpoints or examine data in the library until after
3342 the library is loaded if the function/data symbols do not have
3345 GDB can now also read debug symbols produced by the HP C compiler on
3346 HPPAs (sorry, no C++, Fortran or 68k support).
3348 * Target byte order now dynamically selectable
3350 You can choose which byte order to use with a target system, via the
3351 commands "set endian big" and "set endian little", and you can see the
3352 current setting by using "show endian". You can also give the command
3353 "set endian auto", in which case GDB will use the byte order
3354 associated with the executable. Currently, only embedded MIPS
3355 configurations support dynamic selection of target byte order.
3357 * New DOS host serial code
3359 This version uses DPMI interrupts to handle buffered I/O, so you
3360 no longer need to run asynctsr when debugging boards connected to
3363 *** Changes in GDB-4.13:
3365 * New "complete" command
3367 This lists all the possible completions for the rest of the line, if it
3368 were to be given as a command itself. This is intended for use by emacs.
3370 * Trailing space optional in prompt
3372 "set prompt" no longer adds a space for you after the prompt you set. This
3373 allows you to set a prompt which ends in a space or one that does not.
3375 * Breakpoint hit counts
3377 "info break" now displays a count of the number of times the breakpoint
3378 has been hit. This is especially useful in conjunction with "ignore"; you
3379 can ignore a large number of breakpoint hits, look at the breakpoint info
3380 to see how many times the breakpoint was hit, then run again, ignoring one
3381 less than that number, and this will get you quickly to the last hit of
3384 * Ability to stop printing at NULL character
3386 "set print null-stop" will cause GDB to stop printing the characters of
3387 an array when the first NULL is encountered. This is useful when large
3388 arrays actually contain only short strings.
3390 * Shared library breakpoints
3392 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3393 breakpoints in shared libraries before the executable is run.
3395 * Hardware watchpoints
3397 There is a new hardware breakpoint for the watch command for sparclite
3398 targets. See gdb/sparclite/hw_breakpoint.note.
3400 Hardware watchpoints are also now supported under GNU/Linux.
3404 Annotations have been added. These are for use with graphical interfaces,
3405 and are still experimental. Currently only gdba.el uses these.
3407 * Improved Irix 5 support
3409 GDB now works properly with Irix 5.2.
3411 * Improved HPPA support
3413 GDB now works properly with the latest GCC and GAS.
3415 * New native configurations
3417 Sequent PTX4 i[34]86-sequent-ptx4
3418 HPPA running OSF/1 hppa*-*-osf*
3419 Atari TT running SVR4 m68*-*-sysv4*
3420 RS/6000 LynxOS rs6000-*-lynxos*
3424 OS/9000 i[34]86-*-os9k
3425 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3428 * Hitachi SH7000 and E7000-PC ICE support
3430 There is now support for communicating with the Hitachi E7000-PC ICE.
3431 This is available automatically when GDB is configured for the SH.
3435 As usual, a variety of small fixes and improvements, both generic
3436 and configuration-specific. See the ChangeLog for more detail.
3438 *** Changes in GDB-4.12:
3440 * Irix 5 is now supported
3444 GDB-4.12 on the HPPA has a number of changes which make it unable
3445 to debug the output from the currently released versions of GCC and
3446 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3447 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3448 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3451 *** Changes in GDB-4.11:
3453 * User visible changes:
3457 The "set remotedebug" option is now consistent between the mips remote
3458 target, remote targets using the gdb-specific protocol, UDI (AMD's
3459 debug protocol for the 29k) and the 88k bug monitor. It is now an
3460 integer specifying a debug level (normally 0 or 1, but 2 means more
3461 debugging info for the mips target).
3463 * DEC Alpha native support
3465 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3466 debug info, but GDB works fairly well with the DEC compiler and should
3467 work with a future GCC release. See the README file for a few
3468 Alpha-specific notes.
3470 * Preliminary thread implementation
3472 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3474 * LynxOS native and target support for 386
3476 This release has been hosted on LynxOS 2.2, and also can be configured
3477 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3480 * Improvements in C++ mangling/demangling.
3482 This release has much better g++ debugging, specifically in name
3483 mangling/demangling, virtual function calls, print virtual table,
3484 call methods, ...etc.
3486 *** Changes in GDB-4.10:
3488 * User visible changes:
3490 Remote debugging using the GDB-specific (`target remote') protocol now
3491 supports the `load' command. This is only useful if you have some
3492 other way of getting the stub to the target system, and you can put it
3493 somewhere in memory where it won't get clobbered by the download.
3495 Filename completion now works.
3497 When run under emacs mode, the "info line" command now causes the
3498 arrow to point to the line specified. Also, "info line" prints
3499 addresses in symbolic form (as well as hex).
3501 All vxworks based targets now support a user settable option, called
3502 vxworks-timeout. This option represents the number of seconds gdb
3503 should wait for responses to rpc's. You might want to use this if
3504 your vxworks target is, perhaps, a slow software simulator or happens
3505 to be on the far side of a thin network line.
3509 This release contains support for using a DEC alpha as a GDB host for
3510 cross debugging. Native alpha debugging is not supported yet.
3513 *** Changes in GDB-4.9:
3517 This is the first GDB release which is accompanied by a matching testsuite.
3518 The testsuite requires installation of dejagnu, which should be available
3519 via ftp from most sites that carry GNU software.
3523 'Cfront' style demangling has had its name changed to 'ARM' style, to
3524 emphasize that it was written from the specifications in the C++ Annotated
3525 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3526 disclaimers, it still generated too much confusion with users attempting to
3527 use gdb with AT&T cfront.
3531 GDB now uses a standard remote interface to a simulator library.
3532 So far, the library contains simulators for the Zilog Z8001/2, the
3533 Hitachi H8/300, H8/500 and Super-H.
3535 * New targets supported
3537 H8/300 simulator h8300-hitachi-hms or h8300hms
3538 H8/500 simulator h8500-hitachi-hms or h8500hms
3539 SH simulator sh-hitachi-hms or sh
3540 Z8000 simulator z8k-zilog-none or z8ksim
3541 IDT MIPS board over serial line mips-idt-ecoff
3543 Cross-debugging to GO32 targets is supported. It requires a custom
3544 version of the i386-stub.c module which is integrated with the
3545 GO32 memory extender.
3547 * New remote protocols
3549 MIPS remote debugging protocol.
3551 * New source languages supported
3553 This version includes preliminary support for Chill, a Pascal like language
3554 used by telecommunications companies. Chill support is also being integrated
3555 into the GNU compiler, but we don't know when it will be publically available.
3558 *** Changes in GDB-4.8:
3560 * HP Precision Architecture supported
3562 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3563 version of this support was available as a set of patches from the
3564 University of Utah. GDB does not support debugging of programs
3565 compiled with the HP compiler, because HP will not document their file
3566 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3567 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3569 Many problems in the preliminary version have been fixed.
3571 * Faster and better demangling
3573 We have improved template demangling and fixed numerous bugs in the GNU style
3574 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3575 character types (wchar_t) are now supported. Demangling of each symbol is now
3576 only done once, and is cached when the symbol table for a file is read in.
3577 This results in a small increase in memory usage for C programs, a moderate
3578 increase in memory usage for C++ programs, and a fantastic speedup in
3581 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3582 from the specifications in the Annotated Reference Manual, which AT&T's
3583 compiler does not actually implement.
3585 * G++ multiple inheritance compiler problem
3587 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3588 inheritance lattices was reworked to properly discover ambiguities. We
3589 recently found an example which causes this new algorithm to fail in a
3590 very subtle way, producing bad debug information for those classes.
3591 The file 'gcc.patch' (in this directory) can be applied to gcc to
3592 circumvent the problem. A future GCC release will contain a complete
3595 The previous G++ debug info problem (mentioned below for the gdb-4.7
3596 release) is fixed in gcc version 2.3.2.
3598 * Improved configure script
3600 The `configure' script will now attempt to guess your system type if
3601 you don't supply a host system type. The old scheme of supplying a
3602 host system triplet is preferable over using this. All the magic is
3603 done in the new `config.guess' script. Examine it for details.
3605 We have also brought our configure script much more in line with the FSF's
3606 version. It now supports the --with-xxx options. In particular,
3607 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3608 The resulting GDB will not be able to read arbitrary object file formats --
3609 only the format ``expected'' to be used on the configured target system.
3610 We hope to make this the default in a future release.
3612 * Documentation improvements
3614 There's new internal documentation on how to modify GDB, and how to
3615 produce clean changes to the code. We implore people to read it
3616 before submitting changes.
3618 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3619 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3620 `info' files are also provided. To build `info' files from scratch,
3621 you will need the latest `makeinfo' release, which will be available in
3622 a future texinfo-X.Y release.
3624 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3625 We're not sure exactly which versions have this problem, but it has
3626 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3627 or better. If that isn't possible, there is a patch in
3628 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3629 around this problem.
3633 GDB now supports array constants that can be used in expressions typed in by
3634 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3635 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3638 The new directory `gdb/sparclite' contains a program that demonstrates
3639 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3641 * New native hosts supported
3643 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3644 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3646 * New targets supported
3648 AMD 29k family via UDI a29k-amd-udi or udi29k
3650 * New file formats supported
3652 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3653 HPUX core files, and SCO 3.2v2 core files.
3657 Attaching to processes now works again; thanks for the many bug reports.
3659 We have also stomped on a bunch of core dumps caused by
3660 printf_filtered("%s") problems.
3662 We eliminated a copyright problem on the rpc and ptrace header files
3663 for VxWorks, which was discovered at the last minute during the 4.7
3664 release. You should now be able to build a VxWorks GDB.
3666 You can now interrupt gdb while an attached process is running. This
3667 will cause the attached process to stop, and give control back to GDB.
3669 We fixed problems caused by using too many file descriptors
3670 for reading symbols from object files and libraries. This was
3671 especially a problem for programs that used many (~100) shared
3674 The `step' command now only enters a subroutine if there is line number
3675 information for the subroutine. Otherwise it acts like the `next'
3676 command. Previously, `step' would enter subroutines if there was
3677 any debugging information about the routine. This avoids problems
3678 when using `cc -g1' on MIPS machines.
3680 * Internal improvements
3682 GDB's internal interfaces have been improved to make it easier to support
3683 debugging of multiple languages in the future.
3685 GDB now uses a common structure for symbol information internally.
3686 Minimal symbols (derived from linkage symbols in object files), partial
3687 symbols (from a quick scan of debug information), and full symbols
3688 contain a common subset of information, making it easier to write
3689 shared code that handles any of them.
3691 * New command line options
3693 We now accept --silent as an alias for --quiet.
3697 The memory-mapped-malloc library is now licensed under the GNU Library
3698 General Public License.
3700 *** Changes in GDB-4.7:
3702 * Host/native/target split
3704 GDB has had some major internal surgery to untangle the support for
3705 hosts and remote targets. Now, when you configure GDB for a remote
3706 target, it will no longer load in all of the support for debugging
3707 local programs on the host. When fully completed and tested, this will
3708 ensure that arbitrary host/target combinations are possible.
3710 The primary conceptual shift is to separate the non-portable code in
3711 GDB into three categories. Host specific code is required any time GDB
3712 is compiled on that host, regardless of the target. Target specific
3713 code relates to the peculiarities of the target, but can be compiled on
3714 any host. Native specific code is everything else: it can only be
3715 built when the host and target are the same system. Child process
3716 handling and core file support are two common `native' examples.
3718 GDB's use of /proc for controlling Unix child processes is now cleaner.
3719 It has been split out into a single module under the `target_ops' vector,
3720 plus two native-dependent functions for each system that uses /proc.
3722 * New hosts supported
3724 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3725 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3726 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3728 * New targets supported
3730 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3731 68030 and CPU32 m68030-*-*, m68332-*-*
3733 * New native hosts supported
3735 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3736 (386bsd is not well tested yet)
3737 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3739 * New file formats supported
3741 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3742 supports reading of `a.out.adobe' object files, which are an a.out
3743 format extended with minimal information about multiple sections.
3747 `show copying' is the same as the old `info copying'.
3748 `show warranty' is the same as `info warrantee'.
3749 These were renamed for consistency. The old commands continue to work.
3751 `info handle' is a new alias for `info signals'.
3753 You can now define pre-command hooks, which attach arbitrary command
3754 scripts to any command. The commands in the hook will be executed
3755 prior to the user's command. You can also create a hook which will be
3756 executed whenever the program stops. See gdb.texinfo.
3760 We now deal with Cfront style name mangling, and can even extract type
3761 info from mangled symbols. GDB can automatically figure out which
3762 symbol mangling style your C++ compiler uses.
3764 Calling of methods and virtual functions has been improved as well.
3768 The crash that occured when debugging Sun Ansi-C compiled binaries is
3769 fixed. This was due to mishandling of the extra N_SO stabs output
3772 We also finally got Ultrix 4.2 running in house, and fixed core file
3773 support, with help from a dozen people on the net.
3775 John M. Farrell discovered that the reason that single-stepping was so
3776 slow on all of the Mips based platforms (primarily SGI and DEC) was
3777 that we were trying to demangle and lookup a symbol used for internal
3778 purposes on every instruction that was being stepped through. Changing
3779 the name of that symbol so that it couldn't be mistaken for a C++
3780 mangled symbol sped things up a great deal.
3782 Rich Pixley sped up symbol lookups in general by getting much smarter
3783 about when C++ symbol mangling is necessary. This should make symbol
3784 completion (TAB on the command line) much faster. It's not as fast as
3785 we'd like, but it's significantly faster than gdb-4.6.
3789 A new user controllable variable 'call_scratch_address' can
3790 specify the location of a scratch area to be used when GDB
3791 calls a function in the target. This is necessary because the
3792 usual method of putting the scratch area on the stack does not work
3793 in systems that have separate instruction and data spaces.
3795 We integrated changes to support the 29k UDI (Universal Debugger
3796 Interface), but discovered at the last minute that we didn't have all
3797 of the appropriate copyright paperwork. We are working with AMD to
3798 resolve this, and hope to have it available soon.
3802 We have sped up the remote serial line protocol, especially for targets
3803 with lots of registers. It now supports a new `expedited status' ('T')
3804 message which can be used in place of the existing 'S' status message.
3805 This allows the remote stub to send only the registers that GDB
3806 needs to make a quick decision about single-stepping or conditional
3807 breakpoints, eliminating the need to fetch the entire register set for
3808 each instruction being stepped through.
3810 The GDB remote serial protocol now implements a write-through cache for
3811 registers, only re-reading the registers if the target has run.
3813 There is also a new remote serial stub for SPARC processors. You can
3814 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3815 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3816 processor with a serial port.
3820 Configure.in files have become much easier to read and modify. A new
3821 `table driven' format makes it more obvious what configurations are
3822 supported, and what files each one uses.
3826 There is a new opcodes library which will eventually contain all of the
3827 disassembly routines and opcode tables. At present, it only contains
3828 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3829 disassembler (binutils/objdump) to share these routines.
3831 The libiberty library is now copylefted under the GNU Library General
3832 Public License. This allows more liberal use, and was done so libg++
3833 can use it. This makes no difference to GDB, since the Library License
3834 grants all the rights from the General Public License.
3838 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3839 reference to the stabs symbol info used by the debugger. It is (as far
3840 as we know) the only published document on this fascinating topic. We
3841 encourage you to read it, compare it to the stabs information on your
3842 system, and send improvements on the document in general (to
3843 bug-gdb@prep.ai.mit.edu).
3845 And, of course, many bugs have been fixed.
3848 *** Changes in GDB-4.6:
3850 * Better support for C++ function names
3852 GDB now accepts as input the "demangled form" of C++ overloaded function
3853 names and member function names, and can do command completion on such names
3854 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3855 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3856 Make use of command completion, it is your friend.
3858 GDB also now accepts a variety of C++ mangled symbol formats. They are
3859 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3860 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3861 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3862 for the list of formats.
3864 * G++ symbol mangling problem
3866 Recent versions of gcc have a bug in how they emit debugging information for
3867 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3868 directory) can be applied to gcc to fix the problem. Alternatively, if you
3869 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3870 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3871 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3874 * New 'maintenance' command
3876 All of the commands related to hacking GDB internals have been moved out of
3877 the main command set, and now live behind the 'maintenance' command. This
3878 can also be abbreviated as 'mt'. The following changes were made:
3880 dump-me -> maintenance dump-me
3881 info all-breakpoints -> maintenance info breakpoints
3882 printmsyms -> maintenance print msyms
3883 printobjfiles -> maintenance print objfiles
3884 printpsyms -> maintenance print psymbols
3885 printsyms -> maintenance print symbols
3887 The following commands are new:
3889 maintenance demangle Call internal GDB demangler routine to
3890 demangle a C++ link name and prints the result.
3891 maintenance print type Print a type chain for a given symbol
3893 * Change to .gdbinit file processing
3895 We now read the $HOME/.gdbinit file before processing the argv arguments
3896 (e.g. reading symbol files or core files). This allows global parameters to
3897 be set, which will apply during the symbol reading. The ./.gdbinit is still
3898 read after argv processing.
3900 * New hosts supported
3902 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3904 GNU/Linux support i386-unknown-linux or linux
3906 We are also including code to support the HP/PA running BSD and HPUX. This
3907 is almost guaranteed not to work, as we didn't have time to test or build it
3908 for this release. We are including it so that the more adventurous (or
3909 masochistic) of you can play with it. We also had major problems with the
3910 fact that the compiler that we got from HP doesn't support the -g option.
3913 * New targets supported
3915 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3917 * More smarts about finding #include files
3919 GDB now remembers the compilation directory for all include files, and for
3920 all files from which C is generated (like yacc and lex sources). This
3921 greatly improves GDB's ability to find yacc/lex sources, and include files,
3922 especially if you are debugging your program from a directory different from
3923 the one that contains your sources.
3925 We also fixed a bug which caused difficulty with listing and setting
3926 breakpoints in include files which contain C code. (In the past, you had to
3927 try twice in order to list an include file that you hadn't looked at before.)
3929 * Interesting infernals change
3931 GDB now deals with arbitrary numbers of sections, where the symbols for each
3932 section must be relocated relative to that section's landing place in the
3933 target's address space. This work was needed to support ELF with embedded
3934 stabs used by Solaris-2.0.
3936 * Bug fixes (of course!)
3938 There have been loads of fixes for the following things:
3939 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3940 i960, stabs, DOS(GO32), procfs, etc...
3942 See the ChangeLog for details.
3944 *** Changes in GDB-4.5:
3946 * New machines supported (host and target)
3948 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3950 SGI Irix-4.x mips-sgi-irix4 or iris4
3952 * New malloc package
3954 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3955 Mmalloc is capable of handling mutiple heaps of memory. It is also
3956 capable of saving a heap to a file, and then mapping it back in later.
3957 This can be used to greatly speedup the startup of GDB by using a
3958 pre-parsed symbol table which lives in a mmalloc managed heap. For
3959 more details, please read mmalloc/mmalloc.texi.
3963 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3964 'help info proc' for details.
3966 * MIPS ecoff symbol table format
3968 The code that reads MIPS symbol table format is now supported on all hosts.
3969 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3972 * File name changes for MS-DOS
3974 Many files in the config directories have been renamed to make it easier to
3975 support GDB on MS-DOSe systems (which have very restrictive file name
3976 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3977 environment) is close to working but has some remaining problems. Note
3978 that debugging of DOS programs is not supported, due to limitations
3979 in the ``operating system'', but it can be used to host cross-debugging.
3981 * Cross byte order fixes
3983 Many fixes have been made to support cross debugging of Sparc and MIPS
3984 targets from hosts whose byte order differs.
3986 * New -mapped and -readnow options
3988 If memory-mapped files are available on your system through the 'mmap'
3989 system call, you can use the -mapped option on the `file' or
3990 `symbol-file' commands to cause GDB to write the symbols from your
3991 program into a reusable file. If the program you are debugging is
3992 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3993 Future GDB debugging sessions will notice the presence of this file,
3994 and will quickly map in symbol information from it, rather than reading
3995 the symbol table from the executable program. Using the '-mapped'
3996 option in a GDB `file' or `symbol-file' command has the same effect as
3997 starting GDB with the '-mapped' command-line option.
3999 You can cause GDB to read the entire symbol table immediately by using
4000 the '-readnow' option with any of the commands that load symbol table
4001 information (or on the GDB command line). This makes the command
4002 slower, but makes future operations faster.
4004 The -mapped and -readnow options are typically combined in order to
4005 build a `fred.syms' file that contains complete symbol information.
4006 A simple GDB invocation to do nothing but build a `.syms' file for future
4009 gdb -batch -nx -mapped -readnow programname
4011 The `.syms' file is specific to the host machine on which GDB is run.
4012 It holds an exact image of GDB's internal symbol table. It cannot be
4013 shared across multiple host platforms.
4015 * longjmp() handling
4017 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4018 siglongjmp() without losing control. This feature has not yet been ported to
4019 all systems. It currently works on many 386 platforms, all MIPS-based
4020 platforms (SGI, DECstation, etc), and Sun3/4.
4024 Preliminary work has been put in to support the new Solaris OS from Sun. At
4025 this time, it can control and debug processes, but it is not capable of
4030 As always, many many bug fixes. The major areas were with g++, and mipsread.
4031 People using the MIPS-based platforms should experience fewer mysterious
4032 crashes and trashed symbol tables.
4034 *** Changes in GDB-4.4:
4036 * New machines supported (host and target)
4038 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4040 BSD Reno on Vax vax-dec-bsd
4041 Ultrix on Vax vax-dec-ultrix
4043 * New machines supported (target)
4045 AMD 29000 embedded, using EBMON a29k-none-none
4049 GDB continues to improve its handling of C++. `References' work better.
4050 The demangler has also been improved, and now deals with symbols mangled as
4051 per the Annotated C++ Reference Guide.
4053 GDB also now handles `stabs' symbol information embedded in MIPS
4054 `ecoff' symbol tables. Since the ecoff format was not easily
4055 extensible to handle new languages such as C++, this appeared to be a
4056 good way to put C++ debugging info into MIPS binaries. This option
4057 will be supported in the GNU C compiler, version 2, when it is
4060 * New features for SVR4
4062 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4063 shared libraries. Debugging dynamically linked programs should present
4064 only minor differences from debugging statically linked programs.
4066 The `info proc' command will print out information about any process
4067 on an SVR4 system (including the one you are debugging). At the moment,
4068 it prints the address mappings of the process.
4070 If you bring up GDB on another SVR4 system, please send mail to
4071 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4073 * Better dynamic linking support in SunOS
4075 Reading symbols from shared libraries which contain debugging symbols
4076 now works properly. However, there remain issues such as automatic
4077 skipping of `transfer vector' code during function calls, which
4078 make it harder to debug code in a shared library, than to debug the
4079 same code linked statically.
4083 GDB is now using the latest `getopt' routines from the FSF. This
4084 version accepts the -- prefix for options with long names. GDB will
4085 continue to accept the old forms (-option and +option) as well.
4086 Various single letter abbreviations for options have been explicity
4087 added to the option table so that they won't get overshadowed in the
4088 future by other options that begin with the same letter.
4092 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4093 Many assorted bugs have been handled. Many more remain to be handled.
4094 See the various ChangeLog files (primarily in gdb and bfd) for details.
4097 *** Changes in GDB-4.3:
4099 * New machines supported (host and target)
4101 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4102 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4103 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4105 * Almost SCO Unix support
4107 We had hoped to support:
4108 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4109 (except for core file support), but we discovered very late in the release
4110 that it has problems with process groups that render gdb unusable. Sorry
4111 about that. I encourage people to fix it and post the fixes.
4113 * Preliminary ELF and DWARF support
4115 GDB can read ELF object files on System V Release 4, and can handle
4116 debugging records for C, in DWARF format, in ELF files. This support
4117 is preliminary. If you bring up GDB on another SVR4 system, please
4118 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4123 GDB now uses the latest `readline' library. One user-visible change
4124 is that two tabs will list possible command completions, which previously
4125 required typing M-? (meta-question mark, or ESC ?).
4129 The `stepi' bug that many of you noticed has been squashed.
4130 Many bugs in C++ have been handled. Many more remain to be handled.
4131 See the various ChangeLog files (primarily in gdb and bfd) for details.
4133 * State of the MIPS world (in case you wondered):
4135 GDB can understand the symbol tables emitted by the compilers
4136 supplied by most vendors of MIPS-based machines, including DEC. These
4137 symbol tables are in a format that essentially nobody else uses.
4139 Some versions of gcc come with an assembler post-processor called
4140 mips-tfile. This program is required if you want to do source-level
4141 debugging of gcc-compiled programs. I believe FSF does not ship
4142 mips-tfile with gcc version 1, but it will eventually come with gcc
4145 Debugging of g++ output remains a problem. g++ version 1.xx does not
4146 really support it at all. (If you're lucky, you should be able to get
4147 line numbers and stack traces to work, but no parameters or local
4148 variables.) With some work it should be possible to improve the
4151 When gcc version 2 is released, you will have somewhat better luck.
4152 However, even then you will get confusing results for inheritance and
4155 We will eventually provide full debugging of g++ output on
4156 DECstations. This will probably involve some kind of stabs-in-ecoff
4157 encapulation, but the details have not been worked out yet.
4160 *** Changes in GDB-4.2:
4162 * Improved configuration
4164 Only one copy of `configure' exists now, and it is not self-modifying.
4165 Porting BFD is simpler.
4169 The `step' and `next' commands now only stop at the first instruction
4170 of a source line. This prevents the multiple stops that used to occur
4171 in switch statements, for-loops, etc. `Step' continues to stop if a
4172 function that has debugging information is called within the line.
4176 Lots of small bugs fixed. More remain.
4178 * New host supported (not target)
4180 Intel 386 PC clone running Mach i386-none-mach
4183 *** Changes in GDB-4.1:
4185 * Multiple source language support
4187 GDB now has internal scaffolding to handle several source languages.
4188 It determines the type of each source file from its filename extension,
4189 and will switch expression parsing and number formatting to match the
4190 language of the function in the currently selected stack frame.
4191 You can also specifically set the language to be used, with
4192 `set language c' or `set language modula-2'.
4196 GDB now has preliminary support for the GNU Modula-2 compiler,
4197 currently under development at the State University of New York at
4198 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4199 continue through the fall of 1991 and into 1992.
4201 Other Modula-2 compilers are currently not supported, and attempting to
4202 debug programs compiled with them will likely result in an error as the
4203 symbol table is read. Feel free to work on it, though!
4205 There are hooks in GDB for strict type checking and range checking,
4206 in the `Modula-2 philosophy', but they do not currently work.
4210 GDB can now write to executable and core files (e.g. patch
4211 a variable's value). You must turn this switch on, specify
4212 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4213 by assigning a new value to a variable. Modifications take
4216 * Automatic SunOS shared library reading
4218 When you run your program, GDB automatically determines where its
4219 shared libraries (if any) have been loaded, and reads their symbols.
4220 The `share' command is no longer needed. This also works when
4221 examining core files.
4225 You can specify the number of lines that the `list' command shows.
4228 * New machines supported (host and target)
4230 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4231 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4232 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4234 * New hosts supported (not targets)
4236 IBM RT/PC: romp-ibm-aix or rtpc
4238 * New targets supported (not hosts)
4240 AMD 29000 embedded with COFF a29k-none-coff
4241 AMD 29000 embedded with a.out a29k-none-aout
4242 Ultracomputer remote kernel debug a29k-nyu-kern
4244 * New remote interfaces
4250 *** Changes in GDB-4.0:
4254 Wide output is wrapped at good places to make the output more readable.
4256 Gdb now supports cross-debugging from a host machine of one type to a
4257 target machine of another type. Communication with the target system
4258 is over serial lines. The ``target'' command handles connecting to the
4259 remote system; the ``load'' command will download a program into the
4260 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4261 also supports debugging of realtime processes running under VxWorks,
4262 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4263 stub on the target system.
4265 New CPUs supported include the AMD 29000 and Intel 960.
4267 GDB now reads object files and symbol tables via a ``binary file''
4268 library, which allows a single copy of GDB to debug programs of multiple
4269 object file types such as a.out and coff.
4271 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4272 refcard.dvi and refcard.ps are available to format it).
4275 * Control-Variable user interface simplified
4277 All variables that control the operation of the debugger can be set
4278 by the ``set'' command, and displayed by the ``show'' command.
4280 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4281 ``Show prompt'' produces the response:
4282 Gdb's prompt is new-gdb=>.
4284 What follows are the NEW set commands. The command ``help set'' will
4285 print a complete list of old and new set commands. ``help set FOO''
4286 will give a longer description of the variable FOO. ``show'' will show
4287 all of the variable descriptions and their current settings.
4289 confirm on/off: Enables warning questions for operations that are
4290 hard to recover from, e.g. rerunning the program while
4291 it is already running. Default is ON.
4293 editing on/off: Enables EMACS style command line editing
4294 of input. Previous lines can be recalled with
4295 control-P, the current line can be edited with control-B,
4296 you can search for commands with control-R, etc.
4299 history filename NAME: NAME is where the gdb command history
4300 will be stored. The default is .gdb_history,
4301 or the value of the environment variable
4304 history size N: The size, in commands, of the command history. The
4305 default is 256, or the value of the environment variable
4308 history save on/off: If this value is set to ON, the history file will
4309 be saved after exiting gdb. If set to OFF, the
4310 file will not be saved. The default is OFF.
4312 history expansion on/off: If this value is set to ON, then csh-like
4313 history expansion will be performed on
4314 command line input. The default is OFF.
4316 radix N: Sets the default radix for input and output. It can be set
4317 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4318 in the current radix, so "set radix 10" is always a no-op.
4320 height N: This integer value is the number of lines on a page. Default
4321 is 24, the current `stty rows'' setting, or the ``li#''
4322 setting from the termcap entry matching the environment
4325 width N: This integer value is the number of characters on a line.
4326 Default is 80, the current `stty cols'' setting, or the ``co#''
4327 setting from the termcap entry matching the environment
4330 Note: ``set screensize'' is obsolete. Use ``set height'' and
4331 ``set width'' instead.
4333 print address on/off: Print memory addresses in various command displays,
4334 such as stack traces and structure values. Gdb looks
4335 more ``symbolic'' if you turn this off; it looks more
4336 ``machine level'' with it on. Default is ON.
4338 print array on/off: Prettyprint arrays. New convenient format! Default
4341 print demangle on/off: Print C++ symbols in "source" form if on,
4344 print asm-demangle on/off: Same, for assembler level printouts
4347 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4350 * Support for Epoch Environment.
4352 The epoch environment is a version of Emacs v18 with windowing. One
4353 new command, ``inspect'', is identical to ``print'', except that if you
4354 are running in the epoch environment, the value is printed in its own
4358 * Support for Shared Libraries
4360 GDB can now debug programs and core files that use SunOS shared libraries.
4361 Symbols from a shared library cannot be referenced
4362 before the shared library has been linked with the program (this
4363 happens after you type ``run'' and before the function main() is entered).
4364 At any time after this linking (including when examining core files
4365 from dynamically linked programs), gdb reads the symbols from each
4366 shared library when you type the ``sharedlibrary'' command.
4367 It can be abbreviated ``share''.
4369 sharedlibrary REGEXP: Load shared object library symbols for files
4370 matching a unix regular expression. No argument
4371 indicates to load symbols for all shared libraries.
4373 info sharedlibrary: Status of loaded shared libraries.
4378 A watchpoint stops execution of a program whenever the value of an
4379 expression changes. Checking for this slows down execution
4380 tremendously whenever you are in the scope of the expression, but is
4381 quite useful for catching tough ``bit-spreader'' or pointer misuse
4382 problems. Some machines such as the 386 have hardware for doing this
4383 more quickly, and future versions of gdb will use this hardware.
4385 watch EXP: Set a watchpoint (breakpoint) for an expression.
4387 info watchpoints: Information about your watchpoints.
4389 delete N: Deletes watchpoint number N (same as breakpoints).
4390 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4391 enable N: Re-enables watchpoint number N (same as breakpoints).
4394 * C++ multiple inheritance
4396 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4399 * C++ exception handling
4401 Gdb now supports limited C++ exception handling. Besides the existing
4402 ability to breakpoint on an exception handler, gdb can breakpoint on
4403 the raising of an exception (before the stack is peeled back to the
4406 catch FOO: If there is a FOO exception handler in the dynamic scope,
4407 set a breakpoint to catch exceptions which may be raised there.
4408 Multiple exceptions (``catch foo bar baz'') may be caught.
4410 info catch: Lists all exceptions which may be caught in the
4411 current stack frame.
4414 * Minor command changes
4416 The command ``call func (arg, arg, ...)'' now acts like the print
4417 command, except it does not print or save a value if the function's result
4418 is void. This is similar to dbx usage.
4420 The ``up'' and ``down'' commands now always print the frame they end up
4421 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4422 frames without printing.
4424 * New directory command
4426 'dir' now adds directories to the FRONT of the source search path.
4427 The path starts off empty. Source files that contain debug information
4428 about the directory in which they were compiled can be found even
4429 with an empty path; Sun CC and GCC include this information. If GDB can't
4430 find your source file in the current directory, type "dir .".
4432 * Configuring GDB for compilation
4434 For normal use, type ``./configure host''. See README or gdb.texinfo
4437 GDB now handles cross debugging. If you are remotely debugging between
4438 two different machines, type ``./configure host -target=targ''.
4439 Host is the machine where GDB will run; targ is the machine
4440 where the program that you are debugging will run.