1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.2
8 ** GDB values in Python are now callable if the value represents a
9 function. For example, if 'some_value' represents a function that
10 takes two integer parameters and returns a value, you can call
11 that function like so:
13 result = some_value (10,20)
17 ** GDB now puts template parameters in scope when debugging in an
18 instantiation. For example, if you have:
20 template<int X> int func (void) { return X; }
22 then if you step into func<5>, "print X" will show "5". This
23 feature requires proper debuginfo support from the compiler; it
26 * GDB now has some support for using labels in the program's source in
27 linespecs. For instance, you can use "advance label" to continue
30 * GDB now has support for reading and writing a new .gdb_index
31 section. This section holds a fast index of DWARF debugging
32 information and can be used to greatly speed up GDB startup and
33 operation. See the documentation for `save gdb-index' for details.
35 * The "watch" command now accepts an optional "-location" argument.
36 When used, this causes GDB to watch the memory referred to by the
37 expression. Such a watchpoint is never deleted due to it going out
40 * GDB now supports thread debugging of core dumps on GNU/Linux.
42 GDB now activates thread debugging using the libthread_db library
43 when debugging GNU/Linux core dumps, similarly to when debugging
44 live processes. As a result, when debugging a core dump file, GDB
45 is now able to display pthread_t ids of threads. For example, "info
46 threads" shows the same output as when debugging the process when it
47 was live. In earlier releases, you'd see something like this:
50 * 1 LWP 6780 main () at main.c:10
52 While now you see this:
55 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
57 It is also now possible to inspect TLS variables when debugging core
60 When debugging a core dump generated on a machine other than the one
61 used to run GDB, you may need to point GDB at the correct
62 libthread_db library with the "set libthread-db-search-path"
63 command. See the user manual for more details on this command.
65 * New features in the GDB remote stub, GDBserver
67 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
68 and i686 LynxOS (version 5.x).
70 * Ada task switching is now supported on sparc-elf targets when
71 debugging a program using the Ravenscar Profile. For more information,
72 see the "Tasking Support when using the Ravenscar Profile" section
73 in the GDB user manual.
75 *** Changes in GDB 7.2
77 * Shared library support for remote targets by default
79 When GDB is configured for a generic, non-OS specific target, like
80 for example, --target=arm-eabi or one of the many *-*-elf targets,
81 GDB now queries remote stubs for loaded shared libraries using the
82 `qXfer:libraries:read' packet. Previously, shared library support
83 was always disabled for such configurations.
87 ** Argument Dependent Lookup (ADL)
89 In C++ ADL lookup directs function search to the namespaces of its
90 arguments even if the namespace has not been imported.
100 Here the compiler will search for `foo' in the namespace of 'b'
101 and find A::foo. GDB now supports this. This construct is commonly
102 used in the Standard Template Library for operators.
104 ** Improved User Defined Operator Support
106 In addition to member operators, GDB now supports lookup of operators
107 defined in a namespace and imported with a `using' directive, operators
108 defined in the global scope, operators imported implicitly from an
109 anonymous namespace, and the ADL operators mentioned in the previous
111 GDB now also supports proper overload resolution for all the previously
112 mentioned flavors of operators.
114 ** static const class members
116 Printing of static const class members that are initialized in the
117 class definition has been fixed.
119 * Windows Thread Information Block access.
121 On Windows targets, GDB now supports displaying the Windows Thread
122 Information Block (TIB) structure. This structure is visible either
123 by using the new command `info w32 thread-information-block' or, by
124 dereferencing the new convenience variable named `$_tlb', a
125 thread-specific pointer to the TIB. This feature is also supported
126 when remote debugging using GDBserver.
130 Static tracepoints are calls in the user program into a tracing
131 library. One such library is a port of the LTTng kernel tracer to
132 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
133 When debugging with GDBserver, GDB now supports combining the GDB
134 tracepoint machinery with such libraries. For example: the user can
135 use GDB to probe a static tracepoint marker (a call from the user
136 program into the tracing library) with the new "strace" command (see
137 "New commands" below). This creates a "static tracepoint" in the
138 breakpoint list, that can be manipulated with the same feature set
139 as fast and regular tracepoints. E.g., collect registers, local and
140 global variables, collect trace state variables, and define
141 tracepoint conditions. In addition, the user can collect extra
142 static tracepoint marker specific data, by collecting the new
143 $_sdata internal variable. When analyzing the trace buffer, you can
144 inspect $_sdata like any other variable available to GDB. For more
145 information, see the "Tracepoints" chapter in GDB user manual. New
146 remote packets have been defined to support static tracepoints, see
147 the "New remote packets" section below.
149 * Better reconstruction of tracepoints after disconnected tracing
151 GDB will attempt to download the original source form of tracepoint
152 definitions when starting a trace run, and then will upload these
153 upon reconnection to the target, resulting in a more accurate
154 reconstruction of the tracepoints that are in use on the target.
158 You can now exercise direct control over the ways that GDB can
159 affect your program. For instance, you can disallow the setting of
160 breakpoints, so that the program can run continuously (assuming
161 non-stop mode). In addition, the "observer" variable is available
162 to switch all of the different controls; in observer mode, GDB
163 cannot affect the target's behavior at all, which is useful for
164 tasks like diagnosing live systems in the field.
166 * The new convenience variable $_thread holds the number of the
173 Return the address of the Windows Thread Information Block of a given thread.
177 In response to several of the tracepoint packets, the target may now
178 also respond with a number of intermediate `qRelocInsn' request
179 packets before the final result packet, to have GDB handle
180 relocating an instruction to execute at a different address. This
181 is particularly useful for stubs that support fast tracepoints. GDB
182 reports support for this feature in the qSupported packet.
186 List static tracepoint markers in the target program.
190 List static tracepoint markers at a given address in the target
193 qXfer:statictrace:read
195 Read the static trace data collected (by a `collect $_sdata'
196 tracepoint action). The remote stub reports support for this packet
197 to gdb's qSupported query.
201 Send the current settings of GDB's permission flags.
205 Send part of the source (textual) form of a tracepoint definition,
206 which includes location, conditional, and action list.
208 * The source command now accepts a -s option to force searching for the
209 script in the source search path even if the script name specifies
212 * New features in the GDB remote stub, GDBserver
214 - GDBserver now support tracepoints (including fast tracepoints, and
215 static tracepoints). The feature is currently supported by the
216 i386-linux and amd64-linux builds. See the "Tracepoints support
217 in gdbserver" section in the manual for more information.
219 GDBserver JIT compiles the tracepoint's conditional agent
220 expression bytecode into native code whenever possible for low
221 overhead dynamic tracepoints conditionals. For such tracepoints,
222 an expression that examines program state is evaluated when the
223 tracepoint is reached, in order to determine whether to capture
224 trace data. If the condition is simple and false, processing the
225 tracepoint finishes very quickly and no data is gathered.
227 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
228 for static tracepoints support.
230 - GDBserver now supports x86_64 Windows 64-bit debugging.
232 * GDB now sends xmlRegisters= in qSupported packet to indicate that
233 it understands register description.
235 * The --batch flag now disables pagination and queries.
237 * X86 general purpose registers
239 GDB now supports reading/writing byte, word and double-word x86
240 general purpose registers directly. This means you can use, say,
241 $ah or $ax to refer, respectively, to the byte register AH and
242 16-bit word register AX that are actually portions of the 32-bit
243 register EAX or 64-bit register RAX.
245 * The `commands' command now accepts a range of breakpoints to modify.
246 A plain `commands' following a command that creates multiple
247 breakpoints affects all the breakpoints set by that command. This
248 applies to breakpoints set by `rbreak', and also applies when a
249 single `break' command creates multiple breakpoints (e.g.,
250 breakpoints on overloaded c++ functions).
252 * The `rbreak' command now accepts a filename specification as part of
253 its argument, limiting the functions selected by the regex to those
254 in the specified file.
256 * Support for remote debugging Windows and SymbianOS shared libraries
257 from Unix hosts has been improved. Non Windows GDB builds now can
258 understand target reported file names that follow MS-DOS based file
259 system semantics, such as file names that include drive letters and
260 use the backslash character as directory separator. This makes it
261 possible to transparently use the "set sysroot" and "set
262 solib-search-path" on Unix hosts to point as host copies of the
263 target's shared libraries. See the new command "set
264 target-file-system-kind" described below, and the "Commands to
265 specify files" section in the user manual for more information.
269 eval template, expressions...
270 Convert the values of one or more expressions under the control
271 of the string template to a command line, and call it.
273 set target-file-system-kind unix|dos-based|auto
274 show target-file-system-kind
275 Set or show the assumed file system kind for target reported file
278 save breakpoints <filename>
279 Save all current breakpoint definitions to a file suitable for use
280 in a later debugging session. To read the saved breakpoint
281 definitions, use the `source' command.
283 `save tracepoints' is a new alias for `save-tracepoints'. The latter
286 info static-tracepoint-markers
287 Display information about static tracepoint markers in the target.
289 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
290 Define a static tracepoint by probing a marker at the given
291 function, line, address, or marker ID.
295 Enable and disable observer mode.
297 set may-write-registers on|off
298 set may-write-memory on|off
299 set may-insert-breakpoints on|off
300 set may-insert-tracepoints on|off
301 set may-insert-fast-tracepoints on|off
302 set may-interrupt on|off
303 Set individual permissions for GDB effects on the target. Note that
304 some of these settings can have undesirable or surprising
305 consequences, particularly when changed in the middle of a session.
306 For instance, disabling the writing of memory can prevent
307 breakpoints from being inserted, cause single-stepping to fail, or
308 even crash your program, if you disable after breakpoints have been
309 inserted. However, GDB should not crash.
311 set record memory-query on|off
312 show record memory-query
313 Control whether to stop the inferior if memory changes caused
314 by an instruction cannot be recorded.
319 The disassemble command now supports "start,+length" form of two arguments.
323 ** GDB now provides a new directory location, called the python directory,
324 where Python scripts written for GDB can be installed. The location
325 of that directory is <data-directory>/python, where <data-directory>
326 is the GDB data directory. For more details, see section `Scripting
327 GDB using Python' in the manual.
329 ** The GDB Python API now has access to breakpoints, symbols, symbol
330 tables, program spaces, inferiors, threads and frame's code blocks.
331 Additionally, GDB Parameters can now be created from the API, and
332 manipulated via set/show in the CLI.
334 ** New functions gdb.target_charset, gdb.target_wide_charset,
335 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
337 ** New exception gdb.GdbError.
339 ** Pretty-printers are now also looked up in the current program space.
341 ** Pretty-printers can now be individually enabled and disabled.
343 ** GDB now looks for names of Python scripts to auto-load in a
344 special section named `.debug_gdb_scripts', in addition to looking
345 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
347 * Tracepoint actions were unified with breakpoint commands. In particular,
348 there are no longer differences in "info break" output for breakpoints and
349 tracepoints and the "commands" command can be used for both tracepoints and
354 ARM Symbian arm*-*-symbianelf*
356 * D language support.
357 GDB now supports debugging programs written in the D programming
360 * GDB now supports the extended ptrace interface for PowerPC which is
361 available since Linux kernel version 2.6.34. This automatically enables
362 any hardware breakpoints and additional hardware watchpoints available in
363 the processor. The old ptrace interface exposes just one hardware
364 watchpoint and no hardware breakpoints.
366 * GDB is now able to use the Data Value Compare (DVC) register available on
367 embedded PowerPC processors to implement in hardware simple watchpoint
368 conditions of the form:
370 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
372 This works in native GDB running on Linux kernels with the extended ptrace
373 interface mentioned above.
375 *** Changes in GDB 7.1
381 GDB now supports importing of namespaces in C++. This enables the
382 user to inspect variables from imported namespaces. Support for
383 namepace aliasing has also been added. So, if a namespace is
384 aliased in the current scope (e.g. namepace C=A; ) the user can
385 print variables using the alias (e.g. (gdb) print C::x).
389 All known bugs relating to the printing of virtual base class were
390 fixed. It is now possible to call overloaded static methods using a
395 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
396 and reinterpret_cast<> are now handled by the C++ expression parser.
400 Xilinx MicroBlaze microblaze-*-*
405 Xilinx MicroBlaze microblaze
408 * Multi-program debugging.
410 GDB now has support for multi-program (a.k.a. multi-executable or
411 multi-exec) debugging. This allows for debugging multiple inferiors
412 simultaneously each running a different program under the same GDB
413 session. See "Debugging Multiple Inferiors and Programs" in the
414 manual for more information. This implied some user visible changes
415 in the multi-inferior support. For example, "info inferiors" now
416 lists inferiors that are not running yet or that have exited
417 already. See also "New commands" and "New options" below.
419 * New tracing features
421 GDB's tracepoint facility now includes several new features:
423 ** Trace state variables
425 GDB tracepoints now include support for trace state variables, which
426 are variables managed by the target agent during a tracing
427 experiment. They are useful for tracepoints that trigger each
428 other, so for instance one tracepoint can count hits in a variable,
429 and then a second tracepoint has a condition that is true when the
430 count reaches a particular value. Trace state variables share the
431 $-syntax of GDB convenience variables, and can appear in both
432 tracepoint actions and condition expressions. Use the "tvariable"
433 command to create, and "info tvariables" to view; see "Trace State
434 Variables" in the manual for more detail.
438 GDB now includes an option for defining fast tracepoints, which
439 targets may implement more efficiently, such as by installing a jump
440 into the target agent rather than a trap instruction. The resulting
441 speedup can be by two orders of magnitude or more, although the
442 tradeoff is that some program locations on some target architectures
443 might not allow fast tracepoint installation, for instance if the
444 instruction to be replaced is shorter than the jump. To request a
445 fast tracepoint, use the "ftrace" command, with syntax identical to
446 the regular trace command.
448 ** Disconnected tracing
450 It is now possible to detach GDB from the target while it is running
451 a trace experiment, then reconnect later to see how the experiment
452 is going. In addition, a new variable disconnected-tracing lets you
453 tell the target agent whether to continue running a trace if the
454 connection is lost unexpectedly.
458 GDB now has the ability to save the trace buffer into a file, and
459 then use that file as a target, similarly to you can do with
460 corefiles. You can select trace frames, print data that was
461 collected in them, and use tstatus to display the state of the
462 tracing run at the moment that it was saved. To create a trace
463 file, use "tsave <filename>", and to use it, do "target tfile
466 ** Circular trace buffer
468 You can ask the target agent to handle the trace buffer as a
469 circular buffer, discarding the oldest trace frames to make room for
470 newer ones, by setting circular-trace-buffer to on. This feature may
471 not be available for all target agents.
476 The disassemble command, when invoked with two arguments, now requires
477 the arguments to be comma-separated.
480 The info variables command now displays variable definitions. Files
481 which only declare a variable are not shown.
484 The source command is now capable of sourcing Python scripts.
485 This feature is dependent on the debugger being build with Python
488 Related to this enhancement is also the introduction of a new command
489 "set script-extension" (see below).
491 * New commands (for set/show, see "New options" below)
493 record save [<FILENAME>]
494 Save a file (in core file format) containing the process record
495 execution log for replay debugging at a later time.
497 record restore <FILENAME>
498 Restore the process record execution log that was saved at an
499 earlier time, for replay debugging.
501 add-inferior [-copies <N>] [-exec <FILENAME>]
504 clone-inferior [-copies <N>] [ID]
505 Make a new inferior ready to execute the same program another
511 maint info program-spaces
512 List the program spaces loaded into GDB.
514 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
515 show remote interrupt-sequence
516 Allow the user to select one of ^C, a BREAK signal or BREAK-g
517 as the sequence to the remote target in order to interrupt the execution.
518 Ctrl-C is a default. Some system prefers BREAK which is high level of
519 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
520 Magic SysRq g. It is BREAK signal and character 'g'.
522 set remote interrupt-on-connect [on | off]
523 show remote interrupt-on-connect
524 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
525 remote target when gdb connects to it. This is needed when you debug
528 set remotebreak [on | off]
530 Deprecated. Use "set/show remote interrupt-sequence" instead.
532 tvariable $NAME [ = EXP ]
533 Create or modify a trace state variable.
536 List trace state variables and their values.
538 delete tvariable $NAME ...
539 Delete one or more trace state variables.
542 Evaluate the given expressions without collecting anything into the
543 trace buffer. (Valid in tracepoint actions only.)
545 ftrace FN / FILE:LINE / *ADDR
546 Define a fast tracepoint at the given function, line, or address.
548 * New expression syntax
550 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
551 GDB now parses 0b101010 identically with 42.
555 set follow-exec-mode new|same
556 show follow-exec-mode
557 Control whether GDB reuses the same inferior across an exec call or
558 creates a new one. This is useful to be able to restart the old
559 executable after the inferior having done an exec call.
561 set default-collect EXPR, ...
563 Define a list of expressions to be collected at each tracepoint.
564 This is a useful way to ensure essential items are not overlooked,
565 such as registers or a critical global variable.
567 set disconnected-tracing
568 show disconnected-tracing
569 If set to 1, the target is instructed to continue tracing if it
570 loses its connection to GDB. If 0, the target is to stop tracing
573 set circular-trace-buffer
574 show circular-trace-buffer
575 If set to on, the target is instructed to use a circular trace buffer
576 and discard the oldest trace frames instead of stopping the trace due
577 to a full trace buffer. If set to off, the trace stops when the buffer
578 fills up. Some targets may not support this.
580 set script-extension off|soft|strict
581 show script-extension
582 If set to "off", the debugger does not perform any script language
583 recognition, and all sourced files are assumed to be GDB scripts.
584 If set to "soft" (the default), files are sourced according to
585 filename extension, falling back to GDB scripts if the first
587 If set to "strict", files are sourced according to filename extension.
589 set ada trust-PAD-over-XVS on|off
590 show ada trust-PAD-over-XVS
591 If off, activate a workaround against a bug in the debugging information
592 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
593 the GCC sources for more information about the GNAT encoding and
594 PAD types in particular). It is always safe to set this option to
595 off, but this introduces a slight performance penalty. The default
598 * Python API Improvements
600 ** GDB provides the new class gdb.LazyString. This is useful in
601 some pretty-printing cases. The new method gdb.Value.lazy_string
602 provides a simple way to create objects of this type.
604 ** The fields returned by gdb.Type.fields now have an
605 `is_base_class' attribute.
607 ** The new method gdb.Type.range returns the range of an array type.
609 ** The new method gdb.parse_and_eval can be used to parse and
610 evaluate an expression.
615 Define a trace state variable.
618 Get the current value of a trace state variable.
621 Set desired tracing behavior upon disconnection.
624 Set the trace buffer to be linear or circular.
627 Get data about the tracepoints currently in use.
631 Process record now works correctly with hardware watchpoints.
633 Multiple bug fixes have been made to the mips-irix port, making it
634 much more reliable. In particular:
635 - Debugging threaded applications is now possible again. Previously,
636 GDB would hang while starting the program, or while waiting for
637 the program to stop at a breakpoint.
638 - Attaching to a running process no longer hangs.
639 - An error occurring while loading a core file has been fixed.
640 - Changing the value of the PC register now works again. This fixes
641 problems observed when using the "jump" command, or when calling
642 a function from GDB, or even when assigning a new value to $pc.
643 - With the "finish" and "return" commands, the return value for functions
644 returning a small array is now correctly printed.
645 - It is now possible to break on shared library code which gets executed
646 during a shared library init phase (code executed while executing
647 their .init section). Previously, the breakpoint would have no effect.
648 - GDB is now able to backtrace through the signal handler for
649 non-threaded programs.
651 PIE (Position Independent Executable) programs debugging is now supported.
652 This includes debugging execution of PIC (Position Independent Code) shared
653 libraries although for that, it should be possible to run such libraries as an
656 *** Changes in GDB 7.0
658 * GDB now has an interface for JIT compilation. Applications that
659 dynamically generate code can create symbol files in memory and register
660 them with GDB. For users, the feature should work transparently, and
661 for JIT developers, the interface is documented in the GDB manual in the
662 "JIT Compilation Interface" chapter.
664 * Tracepoints may now be conditional. The syntax is as for
665 breakpoints; either an "if" clause appended to the "trace" command,
666 or the "condition" command is available. GDB sends the condition to
667 the target for evaluation using the same bytecode format as is used
668 for tracepoint actions.
670 * The disassemble command now supports: an optional /r modifier, print the
671 raw instructions in hex as well as in symbolic form, and an optional /m
672 modifier to print mixed source+assembly.
674 * Process record and replay
676 In a architecture environment that supports ``process record and
677 replay'', ``process record and replay'' target can record a log of
678 the process execution, and replay it with both forward and reverse
681 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
682 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
683 set execution-direction {forward|reverse}, for targets that support
686 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
687 feature is available with a native GDB running on kernel version
690 * GDB now has support for multi-byte and wide character sets on the
691 target. Strings whose character type is wchar_t, char16_t, or
692 char32_t are now correctly printed. GDB supports wide- and unicode-
693 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
694 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
695 `printf'. This feature requires iconv to work properly; if your
696 system does not have a working iconv, GDB can use GNU libiconv. See
697 the installation instructions for more information.
699 * GDB now supports automatic retrieval of shared library files from
700 remote targets. To use this feature, specify a system root that begins
701 with the `remote:' prefix, either via the `set sysroot' command or via
702 the `--with-sysroot' configure-time option.
704 * "info sharedlibrary" now takes an optional regex of libraries to show,
705 and it now reports if a shared library has no debugging information.
707 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
708 now complete on file names.
710 * When completing in expressions, gdb will attempt to limit
711 completions to allowable structure or union fields, where appropriate.
712 For instance, consider:
714 # struct example { int f1; double f2; };
715 # struct example variable;
718 If the user types TAB at the end of this command line, the available
719 completions will be "f1" and "f2".
721 * Inlined functions are now supported. They show up in backtraces, and
722 the "step", "next", and "finish" commands handle them automatically.
724 * GDB now supports the token-splicing (##) and stringification (#)
725 operators when expanding macros. It also supports variable-arity
728 * GDB now supports inspecting extra signal information, exported by
729 the new $_siginfo convenience variable. The feature is currently
730 implemented on linux ARM, i386 and amd64.
732 * GDB can now display the VFP floating point registers and NEON vector
733 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
734 can provide these registers (requires Linux 2.6.30 or later). Remote
735 and simulator targets may also provide them.
740 Search memory for a sequence of bytes.
743 Turn off `+'/`-' protocol acknowledgments to permit more efficient
744 operation over reliable transport links. Use of this packet is
745 controlled by the `set remote noack-packet' command.
748 Kill the process with the specified process ID. Use this in preference
749 to `k' when multiprocess protocol extensions are supported.
752 Obtains additional operating system information
756 Read or write additional signal information.
758 * Removed remote protocol undocumented extension
760 An undocumented extension to the remote protocol's `S' stop reply
761 packet that permited the stub to pass a process id was removed.
762 Remote servers should use the `T' stop reply packet instead.
764 * GDB now supports multiple function calling conventions according to the
765 DWARF-2 DW_AT_calling_convention function attribute.
767 * The SH target utilizes the aforementioned change to distinguish between gcc
768 and Renesas calling convention. It also adds the new CLI commands
769 `set/show sh calling-convention'.
771 * GDB can now read compressed debug sections, as produced by GNU gold
772 with the --compress-debug-sections=zlib flag.
774 * 64-bit core files are now supported on AIX.
776 * Thread switching is now supported on Tru64.
778 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
779 which will be allocated using malloc later in program execution.
781 * The qXfer:libraries:read remote procotol packet now allows passing a
782 list of section offsets.
784 * On GNU/Linux, GDB can now attach to stopped processes. Several race
785 conditions handling signals delivered during attach or thread creation
786 have also been fixed.
788 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
789 From the user's standpoint, all unqualified instances of True and False
790 are treated as the standard definitions, regardless of context.
792 * GDB now parses C++ symbol and type names more flexibly. For
795 template<typename T> class C { };
798 GDB will now correctly handle all of:
800 ptype C<char const *>
802 ptype C<const char *>
805 * New features in the GDB remote stub, gdbserver
807 - The "--wrapper" command-line argument tells gdbserver to use a
808 wrapper program to launch programs for debugging.
810 - On PowerPC and S/390 targets, it is now possible to use a single
811 gdbserver executable to debug both 32-bit and 64-bit programs.
812 (This requires gdbserver itself to be built as a 64-bit executable.)
814 - gdbserver uses the new noack protocol mode for TCP connections to
815 reduce communications latency, if also supported and enabled in GDB.
817 - Support for the sparc64-linux-gnu target is now included in
820 - The amd64-linux build of gdbserver now supports debugging both
821 32-bit and 64-bit programs.
823 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
824 now support hardware watchpoints, and will use them automatically
829 GDB now has support for scripting using Python. Whether this is
830 available is determined at configure time.
832 New GDB commands can now be written in Python.
834 * Ada tasking support
836 Ada tasks can now be inspected in GDB. The following commands have
840 Print the list of Ada tasks.
842 Print detailed information about task number N.
844 Print the task number of the current task.
846 Switch the context of debugging to task number N.
848 * Support for user-defined prefixed commands. The "define" command can
849 add new commands to existing prefixes, e.g. "target".
851 * Multi-inferior, multi-process debugging.
853 GDB now has generalized support for multi-inferior debugging. See
854 "Debugging Multiple Inferiors" in the manual for more information.
855 Although availability still depends on target support, the command
856 set is more uniform now. The GNU/Linux specific multi-forks support
857 has been migrated to this new framework. This implied some user
858 visible changes; see "New commands" and also "Removed commands"
861 * Target descriptions can now describe the target OS ABI. See the
862 "Target Description Format" section in the user manual for more
865 * Target descriptions can now describe "compatible" architectures
866 to indicate that the target can execute applications for a different
867 architecture in addition to those for the main target architecture.
868 See the "Target Description Format" section in the user manual for
871 * Multi-architecture debugging.
873 GDB now includes general supports for debugging applications on
874 hybrid systems that use more than one single processor architecture
875 at the same time. Each such hybrid architecture still requires
876 specific support to be added. The only hybrid architecture supported
877 in this version of GDB is the Cell Broadband Engine.
879 * GDB now supports integrated debugging of Cell/B.E. applications that
880 use both the PPU and SPU architectures. To enable support for hybrid
881 Cell/B.E. debugging, you need to configure GDB to support both the
882 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
883 --enable-targets configure option.
885 * Non-stop mode debugging.
887 For some targets, GDB now supports an optional mode of operation in
888 which you can examine stopped threads while other threads continue
889 to execute freely. This is referred to as non-stop mode, with the
890 old mode referred to as all-stop mode. See the "Non-Stop Mode"
891 section in the user manual for more information.
893 To be able to support remote non-stop debugging, a remote stub needs
894 to implement the non-stop mode remote protocol extensions, as
895 described in the "Remote Non-Stop" section of the user manual. The
896 GDB remote stub, gdbserver, has been adjusted to support these
897 extensions on linux targets.
899 * New commands (for set/show, see "New options" below)
901 catch syscall [NAME(S) | NUMBER(S)]
902 Catch system calls. Arguments, which should be names of system
903 calls or their numbers, mean catch only those syscalls. Without
904 arguments, every syscall will be caught. When the inferior issues
905 any of the specified syscalls, GDB will stop and announce the system
906 call, both when it is called and when its call returns. This
907 feature is currently available with a native GDB running on the
908 Linux Kernel, under the following architectures: x86, x86_64,
909 PowerPC and PowerPC64.
911 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
913 Search memory for a sequence of bytes.
915 maint set python print-stack
916 maint show python print-stack
917 Show a stack trace when an error is encountered in a Python script.
920 Invoke CODE by passing it to the Python interpreter.
925 These allow macros to be defined, undefined, and listed
929 Show operating system information about processes.
932 List the inferiors currently under GDB's control.
935 Switch focus to inferior number NUM.
938 Detach from inferior number NUM.
941 Kill inferior number NUM.
946 show spu stop-on-load
947 Control whether to stop for new SPE threads during Cell/B.E. debugging.
949 set spu auto-flush-cache
950 show spu auto-flush-cache
951 Control whether to automatically flush the software-managed cache
952 during Cell/B.E. debugging.
954 set sh calling-convention
955 show sh calling-convention
956 Control the calling convention used when calling SH target functions.
960 Control display of timestamps with GDB debugging output.
962 set disassemble-next-line
963 show disassemble-next-line
964 Control display of disassembled source lines or instructions when
967 set remote noack-packet
968 show remote noack-packet
969 Set/show the use of remote protocol QStartNoAckMode packet. See above
970 under "New remote packets."
972 set remote query-attached-packet
973 show remote query-attached-packet
974 Control use of remote protocol `qAttached' (query-attached) packet.
976 set remote read-siginfo-object
977 show remote read-siginfo-object
978 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
981 set remote write-siginfo-object
982 show remote write-siginfo-object
983 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
986 set remote reverse-continue
987 show remote reverse-continue
988 Control use of remote protocol 'bc' (reverse-continue) packet.
990 set remote reverse-step
991 show remote reverse-step
992 Control use of remote protocol 'bs' (reverse-step) packet.
994 set displaced-stepping
995 show displaced-stepping
996 Control displaced stepping mode. Displaced stepping is a way to
997 single-step over breakpoints without removing them from the debuggee.
998 Also known as "out-of-line single-stepping".
1001 show debug displaced
1002 Control display of debugging info for displaced stepping.
1004 maint set internal-error
1005 maint show internal-error
1006 Control what GDB does when an internal error is detected.
1008 maint set internal-warning
1009 maint show internal-warning
1010 Control what GDB does when an internal warning is detected.
1015 Use a wrapper program to launch programs for debugging.
1017 set multiple-symbols (all|ask|cancel)
1018 show multiple-symbols
1019 The value of this variable can be changed to adjust the debugger behavior
1020 when an expression or a breakpoint location contains an ambiguous symbol
1021 name (an overloaded function name, for instance).
1023 set breakpoint always-inserted
1024 show breakpoint always-inserted
1025 Keep breakpoints always inserted in the target, as opposed to inserting
1026 them when resuming the target, and removing them when the target stops.
1027 This option can improve debugger performance on slow remote targets.
1029 set arm fallback-mode (arm|thumb|auto)
1030 show arm fallback-mode
1031 set arm force-mode (arm|thumb|auto)
1033 These commands control how ARM GDB determines whether instructions
1034 are ARM or Thumb. The default for both settings is auto, which uses
1035 the current CPSR value for instructions without symbols; previous
1036 versions of GDB behaved as if "set arm fallback-mode arm".
1038 set disable-randomization
1039 show disable-randomization
1040 Standalone programs run with the virtual address space randomization enabled
1041 by default on some platforms. This option keeps the addresses stable across
1042 multiple debugging sessions.
1046 Control whether other threads are stopped or not when some thread hits
1051 Requests that asynchronous execution is enabled in the target, if available.
1052 In this case, it's possible to resume target in the background, and interact
1053 with GDB while the target is running. "show target-async" displays the
1054 current state of asynchronous execution of the target.
1056 set target-wide-charset
1057 show target-wide-charset
1058 The target-wide-charset is the name of the character set that GDB
1059 uses when printing characters whose type is wchar_t.
1061 set tcp auto-retry (on|off)
1063 set tcp connect-timeout
1064 show tcp connect-timeout
1065 These commands allow GDB to retry failed TCP connections to a remote stub
1066 with a specified timeout period; this is useful if the stub is launched
1067 in parallel with GDB but may not be ready to accept connections immediately.
1069 set libthread-db-search-path
1070 show libthread-db-search-path
1071 Control list of directories which GDB will search for appropriate
1074 set schedule-multiple (on|off)
1075 show schedule-multiple
1076 Allow GDB to resume all threads of all processes or only threads of
1077 the current process.
1081 Use more aggressive caching for accesses to the stack. This improves
1082 performance of remote debugging (particularly backtraces) without
1083 affecting correctness.
1085 set interactive-mode (on|off|auto)
1086 show interactive-mode
1087 Control whether GDB runs in interactive mode (on) or not (off).
1088 When in interactive mode, GDB waits for the user to answer all
1089 queries. Otherwise, GDB does not wait and assumes the default
1090 answer. When set to auto (the default), GDB determines which
1091 mode to use based on the stdin settings.
1096 For program forks, this is replaced by the new more generic `info
1097 inferiors' command. To list checkpoints, you can still use the
1098 `info checkpoints' command, which was an alias for the `info forks'
1102 Replaced by the new `inferior' command. To switch between
1103 checkpoints, you can still use the `restart' command, which was an
1104 alias for the `fork' command.
1107 This is removed, since some targets don't have a notion of
1108 processes. To switch between processes, you can still use the
1109 `inferior' command using GDB's own inferior number.
1112 For program forks, this is replaced by the new more generic `kill
1113 inferior' command. To delete a checkpoint, you can still use the
1114 `delete checkpoint' command, which was an alias for the `delete
1118 For program forks, this is replaced by the new more generic `detach
1119 inferior' command. To detach a checkpoint, you can still use the
1120 `detach checkpoint' command, which was an alias for the `detach
1123 * New native configurations
1125 x86/x86_64 Darwin i[34567]86-*-darwin*
1127 x86_64 MinGW x86_64-*-mingw*
1131 Lattice Mico32 lm32-*
1132 x86 DICOS i[34567]86-*-dicos*
1133 x86_64 DICOS x86_64-*-dicos*
1136 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1137 (mingw32ce) debugging.
1143 These commands were actually not implemented on any target.
1145 *** Changes in GDB 6.8
1147 * New native configurations
1149 NetBSD/hppa hppa*-*netbsd*
1150 Xtensa GNU/Linux xtensa*-*-linux*
1154 NetBSD/hppa hppa*-*-netbsd*
1155 Xtensa GNU/Lunux xtensa*-*-linux*
1157 * Change in command line behavior -- corefiles vs. process ids.
1159 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1160 attaching to process NUMBER fails, GDB no longer attempts to open a
1161 core file named NUMBER. Attaching to a program using the -c option
1162 is no longer supported. Instead, use the '-p' or '--pid' options.
1164 * GDB can now be built as a native debugger for debugging Windows x86
1165 (mingw32) Portable Executable (PE) programs.
1167 * Pending breakpoints no longer change their number when their address
1170 * GDB now supports breakpoints with multiple locations,
1171 including breakpoints on C++ constructors, inside C++ templates,
1172 and in inlined functions.
1174 * GDB's ability to debug optimized code has been improved. GDB more
1175 accurately identifies function bodies and lexical blocks that occupy
1176 more than one contiguous range of addresses.
1178 * Target descriptions can now describe registers for PowerPC.
1180 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1181 registers on PowerPC targets.
1183 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1184 targets even when the libthread_db library is not available.
1186 * The GDB remote stub, gdbserver, now supports the new file transfer
1187 commands (remote put, remote get, and remote delete).
1189 * The GDB remote stub, gdbserver, now supports run and attach in
1190 extended-remote mode.
1192 * hppa*64*-*-hpux11* target broken
1193 The debugger is unable to start a program and fails with the following
1194 error: "Error trying to get information about dynamic linker".
1195 The gdb-6.7 release is also affected.
1197 * GDB now supports the --enable-targets= configure option to allow
1198 building a single GDB executable that supports multiple remote
1199 target architectures.
1201 * GDB now supports debugging C and C++ programs which use the
1202 Decimal Floating Point extension. In addition, the PowerPC target
1203 now has a set of pseudo-registers to inspect decimal float values
1204 stored in two consecutive float registers.
1206 * The -break-insert MI command can optionally create pending
1209 * Improved support for debugging Ada
1210 Many improvements to the Ada language support have been made. These
1212 - Better support for Ada2005 interface types
1213 - Improved handling of arrays and slices in general
1214 - Better support for Taft-amendment types
1215 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1217 - Improved command completion in Ada
1220 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1225 set print frame-arguments (all|scalars|none)
1226 show print frame-arguments
1227 The value of this variable can be changed to control which argument
1228 values should be printed by the debugger when displaying a frame.
1233 Transfer files to and from a remote target, and delete remote files.
1240 Transfer files to and from a remote target, and delete remote files.
1242 * New remote packets
1249 Open, close, read, write, and delete files on the remote system.
1252 Attach to an existing process on the remote system, in extended-remote
1256 Run a new process on the remote system, in extended-remote mode.
1258 *** Changes in GDB 6.7
1260 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1261 bfd, libiberty and opcodes, as revealed by static analysis donated by
1262 Coverity, Inc. (http://scan.coverity.com).
1264 * When looking up multiply-defined global symbols, GDB will now prefer the
1265 symbol definition in the current shared library if it was built using the
1266 -Bsymbolic linker option.
1268 * When the Text User Interface (TUI) is not configured, GDB will now
1269 recognize the -tui command-line option and print a message that the TUI
1272 * The GDB remote stub, gdbserver, now has lower overhead for high
1273 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1275 * GDB for MIPS targets now autodetects whether a remote target provides
1276 32-bit or 64-bit register values.
1278 * Support for C++ member pointers has been improved.
1280 * GDB now understands XML target descriptions, which specify the
1281 target's overall architecture. GDB can read a description from
1282 a local file or over the remote serial protocol.
1284 * Vectors of single-byte data use a new integer type which is not
1285 automatically displayed as character or string data.
1287 * The /s format now works with the print command. It displays
1288 arrays of single-byte integers and pointers to single-byte integers
1291 * Target descriptions can now describe target-specific registers,
1292 for architectures which have implemented the support (currently
1293 only ARM, M68K, and MIPS).
1295 * GDB and the GDB remote stub, gdbserver, now support the XScale
1298 * The GDB remote stub, gdbserver, has been updated to support
1299 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1300 has been rewritten to use the standard GDB remote protocol.
1302 * GDB can now step into C++ functions which are called through thunks.
1304 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1306 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1307 layout. It also supports a TextSeg= and DataSeg= response when only
1308 segment base addresses (rather than offsets) are available.
1310 * The /i format now outputs any trailing branch delay slot instructions
1311 immediately following the last instruction within the count specified.
1313 * The GDB remote protocol "T" stop reply packet now supports a
1314 "library" response. Combined with the new "qXfer:libraries:read"
1315 packet, this response allows GDB to debug shared libraries on targets
1316 where the operating system manages the list of loaded libraries (e.g.
1317 Windows and SymbianOS).
1319 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1320 (DLLs) on Windows and Windows CE targets.
1322 * GDB now supports a faster verification that a .debug file matches its binary
1323 according to its build-id signature, if the signature is present.
1329 Enable or disable hardware flow control (RTS/CTS) on the serial port
1330 when debugging using remote targets.
1332 set mem inaccessible-by-default
1333 show mem inaccessible-by-default
1334 If the target supplies a memory map, for instance via the remote
1335 protocol's "qXfer:memory-map:read" packet, setting this variable
1336 prevents GDB from accessing memory outside the memory map. This
1337 is useful for targets with memory mapped registers or which react
1338 badly to accesses of unmapped address space.
1340 set breakpoint auto-hw
1341 show breakpoint auto-hw
1342 If the target supplies a memory map, for instance via the remote
1343 protocol's "qXfer:memory-map:read" packet, setting this variable
1344 lets GDB use hardware breakpoints automatically for memory regions
1345 where it can not use software breakpoints. This covers both the
1346 "break" command and internal breakpoints used for other commands
1347 including "next" and "finish".
1350 catch exception unhandled
1351 Stop the program execution when Ada exceptions are raised.
1354 Stop the program execution when an Ada assertion failed.
1358 Set an alternate system root for target files. This is a more
1359 general version of "set solib-absolute-prefix", which is now
1360 an alias to "set sysroot".
1363 Provide extended SPU facility status information. This set of
1364 commands is available only when debugging the Cell/B.E. SPU
1367 * New native configurations
1369 OpenBSD/sh sh*-*openbsd*
1372 unset tdesc filename
1374 Use the specified local file as an XML target description, and do
1375 not query the target for its built-in description.
1379 OpenBSD/sh sh*-*-openbsd*
1380 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1381 Toshiba Media Processor mep-elf
1383 * New remote packets
1386 Ignore the specified signals; pass them directly to the debugged program
1387 without stopping other threads or reporting them to GDB.
1389 qXfer:features:read:
1390 Read an XML target description from the target, which describes its
1395 Read or write contents of an spufs file on the target system. These
1396 packets are available only on the Cell/B.E. SPU architecture.
1398 qXfer:libraries:read:
1399 Report the loaded shared libraries. Combined with new "T" packet
1400 response, this packet allows GDB to debug shared libraries on
1401 targets where the operating system manages the list of loaded
1402 libraries (e.g. Windows and SymbianOS).
1406 Support for these obsolete configurations has been removed.
1414 i[34567]86-*-lynxos*
1415 i[34567]86-*-netware*
1416 i[34567]86-*-sco3.2v5*
1417 i[34567]86-*-sco3.2v4*
1419 i[34567]86-*-sysv4.2*
1422 i[34567]86-*-unixware2*
1423 i[34567]86-*-unixware*
1432 * Other removed features
1439 Various m68k-only ROM monitors.
1446 Various Renesas ROM monitors and debugging interfaces for SH and
1451 Support for a Macraigor serial interface to on-chip debugging.
1452 GDB does not directly support the newer parallel or USB
1457 A debug information format. The predecessor to DWARF 2 and
1458 DWARF 3, which are still supported.
1460 Support for the HP aCC compiler on HP-UX/PA-RISC
1462 SOM-encapsulated symbolic debugging information, automatic
1463 invocation of pxdb, and the aCC custom C++ ABI. This does not
1464 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1465 with aCC can still be debugged on an assembly level.
1467 MIPS ".pdr" sections
1469 A MIPS-specific format used to describe stack frame layout
1470 in debugging information.
1474 GDB could work with an older version of Guile to debug
1475 the interpreter and Scheme programs running in it.
1477 set mips stack-arg-size
1478 set mips saved-gpreg-size
1480 Use "set mips abi" to control parameter passing for MIPS.
1482 *** Changes in GDB 6.6
1487 Cell Broadband Engine SPU spu-elf
1489 * GDB can now be configured as a cross-debugger targeting native Windows
1490 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1491 running on a Windows system over TCP/IP to debug Windows programs.
1493 * The GDB remote stub, gdbserver, has been updated to support Windows and
1494 Cygwin debugging. Both single-threaded and multi-threaded programs are
1497 * The "set trust-readonly-sections" command works again. This command was
1498 broken in GDB 6.3, 6.4, and 6.5.
1500 * The "load" command now supports writing to flash memory, if the remote
1501 stub provides the required support.
1503 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1504 longer requires symbolic debug information (e.g. DWARF-2).
1509 unset substitute-path
1510 show substitute-path
1511 Manage a list of substitution rules that GDB uses to rewrite the name
1512 of the directories where the sources are located. This can be useful
1513 for instance when the sources were moved to a different location
1514 between compilation and debugging.
1518 Print each CLI command as it is executed. Each command is prefixed with
1519 a number of `+' symbols representing the nesting depth.
1520 The source command now has a `-v' option to enable the same feature.
1524 The ARM Demon monitor support (RDP protocol, "target rdp").
1526 Kernel Object Display, an embedded debugging feature which only worked with
1527 an obsolete version of Cisco IOS.
1529 The 'set download-write-size' and 'show download-write-size' commands.
1531 * New remote packets
1534 Tell a stub about GDB client features, and request remote target features.
1535 The first feature implemented is PacketSize, which allows the target to
1536 specify the size of packets it can handle - to minimize the number of
1537 packets required and improve performance when connected to a remote
1541 Fetch an OS auxilliary vector from the remote stub. This packet is a
1542 more efficient replacement for qPart:auxv:read.
1544 qXfer:memory-map:read:
1545 Fetch a memory map from the remote stub, including information about
1546 RAM, ROM, and flash memory devices.
1551 Erase and program a flash memory device.
1553 * Removed remote packets
1556 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1557 used it, and only gdbserver implemented it.
1559 *** Changes in GDB 6.5
1563 Renesas M32C/M16C m32c-elf
1565 Morpho Technologies ms1 ms1-elf
1569 init-if-undefined Initialize a convenience variable, but
1570 only if it doesn't already have a value.
1572 The following commands are presently only implemented for native GNU/Linux:
1574 checkpoint Save a snapshot of the program state.
1576 restart <n> Return the program state to a
1577 previously saved state.
1579 info checkpoints List currently saved checkpoints.
1581 delete-checkpoint <n> Delete a previously saved checkpoint.
1583 set|show detach-on-fork Tell gdb whether to detach from a newly
1584 forked process, or to keep debugging it.
1586 info forks List forks of the user program that
1587 are available to be debugged.
1589 fork <n> Switch to debugging one of several
1590 forks of the user program that are
1591 available to be debugged.
1593 delete-fork <n> Delete a fork from the list of forks
1594 that are available to be debugged (and
1595 kill the forked process).
1597 detach-fork <n> Delete a fork from the list of forks
1598 that are available to be debugged (and
1599 allow the process to continue).
1603 Morpho Technologies ms2 ms1-elf
1605 * Improved Windows host support
1607 GDB now builds as a cross debugger hosted on i686-mingw32, including
1608 native console support, and remote communications using either
1609 network sockets or serial ports.
1611 * Improved Modula-2 language support
1613 GDB can now print most types in the Modula-2 syntax. This includes:
1614 basic types, set types, record types, enumerated types, range types,
1615 pointer types and ARRAY types. Procedure var parameters are correctly
1616 printed and hexadecimal addresses and character constants are also
1617 written in the Modula-2 syntax. Best results can be obtained by using
1618 GNU Modula-2 together with the -gdwarf-2 command line option.
1622 The ARM rdi-share module.
1624 The Netware NLM debug server.
1626 *** Changes in GDB 6.4
1628 * New native configurations
1630 OpenBSD/arm arm*-*-openbsd*
1631 OpenBSD/mips64 mips64-*-openbsd*
1635 Morpho Technologies ms1 ms1-elf
1637 * New command line options
1639 --batch-silent As for --batch, but totally silent.
1640 --return-child-result The debugger will exist with the same value
1641 the child (debugged) program exited with.
1642 --eval-command COMMAND, -ex COMMAND
1643 Execute a single GDB CLI command. This may be
1644 specified multiple times and in conjunction
1645 with the --command (-x) option.
1647 * Deprecated commands removed
1649 The following commands, that were deprecated in 2000, have been
1653 set|show arm disassembly-flavor set|show arm disassembler
1654 othernames set arm disassembler
1655 set|show remotedebug set|show debug remote
1656 set|show archdebug set|show debug arch
1657 set|show eventdebug set|show debug event
1660 * New BSD user-level threads support
1662 It is now possible to debug programs using the user-level threads
1663 library on OpenBSD and FreeBSD. Currently supported (target)
1666 FreeBSD/amd64 x86_64-*-freebsd*
1667 FreeBSD/i386 i386-*-freebsd*
1668 OpenBSD/i386 i386-*-openbsd*
1670 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1671 are not yet supported.
1673 * New support for Matsushita MN10300 w/sim added
1674 (Work in progress). mn10300-elf.
1676 * REMOVED configurations and files
1678 VxWorks and the XDR protocol *-*-vxworks
1679 Motorola MCORE mcore-*-*
1680 National Semiconductor NS32000 ns32k-*-*
1682 * New "set print array-indexes" command
1684 After turning this setting "on", GDB prints the index of each element
1685 when displaying arrays. The default is "off" to preserve the previous
1688 * VAX floating point support
1690 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1692 * User-defined command support
1694 In addition to using $arg0..$arg9 for argument passing, it is now possible
1695 to use $argc to determine now many arguments have been passed. See the
1696 section on user-defined commands in the user manual for more information.
1698 *** Changes in GDB 6.3:
1700 * New command line option
1702 GDB now accepts -l followed by a number to set the timeout for remote
1705 * GDB works with GCC -feliminate-dwarf2-dups
1707 GDB now supports a more compact representation of DWARF-2 debug
1708 information using DW_FORM_ref_addr references. These are produced
1709 by GCC with the option -feliminate-dwarf2-dups and also by some
1710 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1711 to use -feliminate-dwarf2-dups.
1713 * Internationalization
1715 When supported by the host system, GDB will be built with
1716 internationalization (libintl). The task of marking up the sources is
1717 continued, we're looking forward to our first translation.
1721 Initial support for debugging programs compiled with the GNAT
1722 implementation of the Ada programming language has been integrated
1723 into GDB. In this release, support is limited to expression evaluation.
1725 * New native configurations
1727 GNU/Linux/m32r m32r-*-linux-gnu
1731 GDB's remote protocol now includes support for the 'p' packet. This
1732 packet is used to fetch individual registers from a remote inferior.
1734 * END-OF-LIFE registers[] compatibility module
1736 GDB's internal register infrastructure has been completely rewritten.
1737 The new infrastructure making possible the implementation of key new
1738 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1741 GDB 6.3 will be the last release to include the the registers[]
1742 compatibility module that allowed out-of-date configurations to
1743 continue to work. This change directly impacts the following
1753 powerpc bdm protocol
1755 Unless there is activity to revive these configurations, they will be
1756 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1758 * OBSOLETE configurations and files
1760 Configurations that have been declared obsolete in this release have
1761 been commented out. Unless there is activity to revive these
1762 configurations, the next release of GDB will have their sources
1763 permanently REMOVED.
1772 *** Changes in GDB 6.2.1:
1774 * MIPS `break main; run' gave an heuristic-fence-post warning
1776 When attempting to run even a simple program, a warning about
1777 heuristic-fence-post being hit would be reported. This problem has
1780 * MIPS IRIX 'long double' crashed GDB
1782 When examining a long double variable, GDB would get a segmentation
1783 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1784 IRIX long double values).
1788 A bug in the VAX stack code was causing problems with the "next"
1789 command. This problem has been fixed.
1791 *** Changes in GDB 6.2:
1793 * Fix for ``many threads''
1795 On GNU/Linux systems that use the NPTL threads library, a program
1796 rapidly creating and deleting threads would confuse GDB leading to the
1799 ptrace: No such process.
1800 thread_db_get_info: cannot get thread info: generic error
1802 This problem has been fixed.
1804 * "-async" and "-noasync" options removed.
1806 Support for the broken "-noasync" option has been removed (it caused
1809 * New ``start'' command.
1811 This command runs the program until the begining of the main procedure.
1813 * New BSD Kernel Data Access Library (libkvm) interface
1815 Using ``target kvm'' it is now possible to debug kernel core dumps and
1816 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1817 platforms. Currently supported (native-only) configurations are:
1819 FreeBSD/amd64 x86_64-*-freebsd*
1820 FreeBSD/i386 i?86-*-freebsd*
1821 NetBSD/i386 i?86-*-netbsd*
1822 NetBSD/m68k m68*-*-netbsd*
1823 NetBSD/sparc sparc-*-netbsd*
1824 OpenBSD/amd64 x86_64-*-openbsd*
1825 OpenBSD/i386 i?86-*-openbsd*
1826 OpenBSD/m68k m68*-openbsd*
1827 OpenBSD/sparc sparc-*-openbsd*
1829 * Signal trampoline code overhauled
1831 Many generic problems with GDB's signal handling code have been fixed.
1832 These include: backtraces through non-contiguous stacks; recognition
1833 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1834 call; backtrace through a signal trampoline; step into and out of
1835 signal handlers; and single-stepping in the signal trampoline.
1837 Please note that kernel bugs are a limiting factor here. These
1838 features have been shown to work on an s390 GNU/Linux system that
1839 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1841 * Cygwin support for DWARF 2 added.
1843 * New native configurations
1845 GNU/Linux/hppa hppa*-*-linux*
1846 OpenBSD/hppa hppa*-*-openbsd*
1847 OpenBSD/m68k m68*-*-openbsd*
1848 OpenBSD/m88k m88*-*-openbsd*
1849 OpenBSD/powerpc powerpc-*-openbsd*
1850 NetBSD/vax vax-*-netbsd*
1851 OpenBSD/vax vax-*-openbsd*
1853 * END-OF-LIFE frame compatibility module
1855 GDB's internal frame infrastructure has been completely rewritten.
1856 The new infrastructure making it possible to support key new features
1857 including DWARF 2 Call Frame Information. To aid in the task of
1858 migrating old configurations to this new infrastructure, a
1859 compatibility module, that allowed old configurations to continue to
1860 work, was also included.
1862 GDB 6.2 will be the last release to include this frame compatibility
1863 module. This change directly impacts the following configurations:
1873 Unless there is activity to revive these configurations, they will be
1874 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1876 * REMOVED configurations and files
1878 Sun 3, running SunOS 3 m68*-*-sunos3*
1879 Sun 3, running SunOS 4 m68*-*-sunos4*
1880 Sun 2, running SunOS 3 m68000-*-sunos3*
1881 Sun 2, running SunOS 4 m68000-*-sunos4*
1882 Motorola 680x0 running LynxOS m68*-*-lynxos*
1883 AT&T 3b1/Unix pc m68*-att-*
1884 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1885 decstation mips-dec-* mips-little-*
1886 riscos mips-*-riscos* mips-*-sysv*
1887 sonymips mips-sony-*
1888 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1890 *** Changes in GDB 6.1.1:
1892 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1894 The TUI (Text-mode User Interface) is now built as part of a default
1895 GDB configuration. It is enabled by either selecting the TUI with the
1896 command line option "-i=tui" or by running the separate "gdbtui"
1897 program. For more information on the TUI, see the manual "Debugging
1900 * Pending breakpoint support (also included in GDB 6.1)
1902 Support has been added to allow you to specify breakpoints in shared
1903 libraries that have not yet been loaded. If a breakpoint location
1904 cannot be found, and the "breakpoint pending" option is set to auto,
1905 GDB queries you if you wish to make the breakpoint pending on a future
1906 shared-library load. If and when GDB resolves the breakpoint symbol,
1907 the pending breakpoint is removed as one or more regular breakpoints
1910 Pending breakpoints are very useful for GCJ Java debugging.
1912 * Fixed ISO-C build problems
1914 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1915 non ISO-C code that stopped them being built using a more strict ISO-C
1916 compiler (e.g., IBM's C compiler).
1918 * Fixed build problem on IRIX 5
1920 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1921 wasn't able to compile compile on an IRIX 5 system.
1923 * Added execute permission to gdb/gdbserver/configure
1925 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1926 permission. This bug would cause configure to fail on a number of
1927 systems (Solaris, IRIX). Ref: server/519.
1929 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1931 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1932 has been updated to use constant array sizes.
1934 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1936 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1937 its generated DWARF Call Frame Info. This encoding was causing GDB to
1938 panic, that panic has been fixed. Ref: gdb/1628.
1940 * Fixed a problem when examining parameters in shared library code.
1942 When examining parameters in optimized shared library code generated
1943 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1944 not available''. GDB now correctly displays the variable's value.
1946 *** Changes in GDB 6.1:
1948 * Removed --with-mmalloc
1950 Support for the mmalloc memory manager has been removed, as it
1951 conflicted with the internal gdb byte cache.
1953 * Changes in AMD64 configurations
1955 The AMD64 target now includes the %cs and %ss registers. As a result
1956 the AMD64 remote protocol has changed; this affects the floating-point
1957 and SSE registers. If you rely on those registers for your debugging,
1958 you should upgrade gdbserver on the remote side.
1960 * Revised SPARC target
1962 The SPARC target has been completely revised, incorporating the
1963 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1964 support for LynxOS and SunOS 4 has been dropped. Calling functions
1965 from within GDB on operating systems with a non-executable stack
1966 (Solaris, OpenBSD) now works.
1970 GDB has a new C++ demangler which does a better job on the mangled
1971 names generated by current versions of g++. It also runs faster, so
1972 with this and other changes gdb should now start faster on large C++
1975 * DWARF 2 Location Expressions
1977 GDB support for location expressions has been extended to support function
1978 arguments and frame bases. Older versions of GDB could crash when they
1981 * C++ nested types and namespaces
1983 GDB's support for nested types and namespaces in C++ has been
1984 improved, especially if you use the DWARF 2 debugging format. (This
1985 is the default for recent versions of GCC on most platforms.)
1986 Specifically, if you have a class "Inner" defined within a class or
1987 namespace "Outer", then GDB realizes that the class's name is
1988 "Outer::Inner", not simply "Inner". This should greatly reduce the
1989 frequency of complaints about not finding RTTI symbols. In addition,
1990 if you are stopped at inside of a function defined within a namespace,
1991 GDB modifies its name lookup accordingly.
1993 * New native configurations
1995 NetBSD/amd64 x86_64-*-netbsd*
1996 OpenBSD/amd64 x86_64-*-openbsd*
1997 OpenBSD/alpha alpha*-*-openbsd*
1998 OpenBSD/sparc sparc-*-openbsd*
1999 OpenBSD/sparc64 sparc64-*-openbsd*
2001 * New debugging protocols
2003 M32R with SDI protocol m32r-*-elf*
2005 * "set prompt-escape-char" command deleted.
2007 The command "set prompt-escape-char" has been deleted. This command,
2008 and its very obscure effet on GDB's prompt, was never documented,
2009 tested, nor mentioned in the NEWS file.
2011 * OBSOLETE configurations and files
2013 Configurations that have been declared obsolete in this release have
2014 been commented out. Unless there is activity to revive these
2015 configurations, the next release of GDB will have their sources
2016 permanently REMOVED.
2018 Sun 3, running SunOS 3 m68*-*-sunos3*
2019 Sun 3, running SunOS 4 m68*-*-sunos4*
2020 Sun 2, running SunOS 3 m68000-*-sunos3*
2021 Sun 2, running SunOS 4 m68000-*-sunos4*
2022 Motorola 680x0 running LynxOS m68*-*-lynxos*
2023 AT&T 3b1/Unix pc m68*-att-*
2024 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2025 decstation mips-dec-* mips-little-*
2026 riscos mips-*-riscos* mips-*-sysv*
2027 sonymips mips-sony-*
2028 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2030 * REMOVED configurations and files
2032 SGI Irix-4.x mips-sgi-irix4 or iris4
2033 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2034 Z8000 simulator z8k-zilog-none or z8ksim
2035 Matsushita MN10200 w/simulator mn10200-*-*
2036 H8/500 simulator h8500-hitachi-hms or h8500hms
2037 HP/PA running BSD hppa*-*-bsd*
2038 HP/PA running OSF/1 hppa*-*-osf*
2039 HP/PA Pro target hppa*-*-pro*
2040 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2041 386BSD i[3456]86-*-bsd*
2042 Sequent family i[3456]86-sequent-sysv4*
2043 i[3456]86-sequent-sysv*
2044 i[3456]86-sequent-bsd*
2045 SPARC running LynxOS sparc-*-lynxos*
2046 SPARC running SunOS 4 sparc-*-sunos4*
2047 Tsqware Sparclet sparclet-*-*
2048 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2050 *** Changes in GDB 6.0:
2054 Support for debugging the Objective-C programming language has been
2055 integrated into GDB.
2057 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2059 DWARF 2's Call Frame Information makes available compiler generated
2060 information that more exactly describes the program's run-time stack.
2061 By using this information, GDB is able to provide more robust stack
2064 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2065 have been updated to use a new backtrace mechanism which includes
2066 DWARF 2 CFI support.
2070 GDB's remote protocol has been extended to include support for hosted
2071 file I/O (where the remote target uses GDB's file system). See GDB's
2072 remote protocol documentation for details.
2074 * All targets using the new architecture framework.
2076 All of GDB's targets have been updated to use the new internal
2077 architecture framework. The way is now open for future GDB releases
2078 to include cross-architecture native debugging support (i386 on amd64,
2081 * GNU/Linux's Thread Local Storage (TLS)
2083 GDB now includes support for for the GNU/Linux implementation of
2084 per-thread variables.
2086 * GNU/Linux's Native POSIX Thread Library (NPTL)
2088 GDB's thread code has been updated to work with either the new
2089 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2091 * Separate debug info.
2093 GDB, in conjunction with BINUTILS, now supports a mechanism for
2094 automatically loading debug information from a separate file. Instead
2095 of shipping full debug and non-debug versions of system libraries,
2096 system integrators can now instead ship just the stripped libraries
2097 and optional debug files.
2099 * DWARF 2 Location Expressions
2101 DWARF 2 Location Expressions allow the compiler to more completely
2102 describe the location of variables (even in optimized code) to the
2105 GDB now includes preliminary support for location expressions (support
2106 for DW_OP_piece is still missing).
2110 A number of long standing bugs that caused GDB to die while starting a
2111 Java application have been fixed. GDB's Java support is now
2112 considered "useable".
2114 * GNU/Linux support for fork, vfork, and exec.
2116 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2117 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2120 * GDB supports logging output to a file
2122 There are two new commands, "set logging" and "show logging", which can be
2123 used to capture GDB's output to a file.
2125 * The meaning of "detach" has changed for gdbserver
2127 The "detach" command will now resume the application, as documented. To
2128 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2131 * d10v, m68hc11 `regs' command deprecated
2133 The `info registers' command has been updated so that it displays the
2134 registers using a format identical to the old `regs' command.
2138 A new command, "maint set profile on/off", has been added. This command can
2139 be used to enable or disable profiling while running GDB, to profile a
2140 session or a set of commands. In addition there is a new configure switch,
2141 "--enable-profiling", which will cause GDB to be compiled with profiling
2142 data, for more informative profiling results.
2144 * Default MI syntax changed to "mi2".
2146 The default MI (machine interface) syntax, enabled by the command line
2147 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2148 "mi1", can be enabled by specifying the option "-i=mi1".
2150 Support for the original "mi0" syntax (included in GDB 5.0) has been
2153 Fix for gdb/192: removed extraneous space when displaying frame level.
2154 Fix for gdb/672: update changelist is now output in mi list format.
2155 Fix for gdb/702: a -var-assign that updates the value now shows up
2156 in a subsequent -var-update.
2158 * New native configurations.
2160 FreeBSD/amd64 x86_64-*-freebsd*
2162 * Multi-arched targets.
2164 HP/PA HPUX11 hppa*-*-hpux*
2165 Renesas M32R/D w/simulator m32r-*-elf*
2167 * OBSOLETE configurations and files
2169 Configurations that have been declared obsolete in this release have
2170 been commented out. Unless there is activity to revive these
2171 configurations, the next release of GDB will have their sources
2172 permanently REMOVED.
2174 Z8000 simulator z8k-zilog-none or z8ksim
2175 Matsushita MN10200 w/simulator mn10200-*-*
2176 H8/500 simulator h8500-hitachi-hms or h8500hms
2177 HP/PA running BSD hppa*-*-bsd*
2178 HP/PA running OSF/1 hppa*-*-osf*
2179 HP/PA Pro target hppa*-*-pro*
2180 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2181 Sequent family i[3456]86-sequent-sysv4*
2182 i[3456]86-sequent-sysv*
2183 i[3456]86-sequent-bsd*
2184 Tsqware Sparclet sparclet-*-*
2185 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2187 * REMOVED configurations and files
2190 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2191 IBM AIX PS/2 i[3456]86-*-aix
2192 i386 running Mach 3.0 i[3456]86-*-mach3*
2193 i386 running Mach i[3456]86-*-mach*
2194 i386 running OSF/1 i[3456]86-*osf1mk*
2195 HP/Apollo 68k Family m68*-apollo*-sysv*,
2197 m68*-hp-bsd*, m68*-hp-hpux*
2198 Argonaut Risc Chip (ARC) arc-*-*
2199 Mitsubishi D30V d30v-*-*
2200 Fujitsu FR30 fr30-*-elf*
2201 OS/9000 i[34]86-*-os9k
2202 I960 with MON960 i960-*-coff
2204 * MIPS $fp behavior changed
2206 The convenience variable $fp, for the MIPS, now consistently returns
2207 the address of the current frame's base. Previously, depending on the
2208 context, $fp could refer to either $sp or the current frame's base
2209 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2210 The GNU Source-Level Debugger''.
2212 *** Changes in GDB 5.3:
2214 * GNU/Linux shared library multi-threaded performance improved.
2216 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2217 `/proc', in preference to `ptrace' for memory reads. This may result
2218 in an improvement in the start-up time of multi-threaded, shared
2219 library applications when run under GDB. One GDB user writes: ``loads
2220 shared libs like mad''.
2222 * ``gdbserver'' now supports multi-threaded applications on some targets
2224 Support for debugging multi-threaded applications which use
2225 the GNU/Linux LinuxThreads package has been added for
2226 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2227 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2229 * GDB now supports C/C++ preprocessor macros.
2231 GDB now expands preprocessor macro invocations in C/C++ expressions,
2232 and provides various commands for showing macro definitions and how
2235 The new command `macro expand EXPRESSION' expands any macro
2236 invocations in expression, and shows the result.
2238 The new command `show macro MACRO-NAME' shows the definition of the
2239 macro named MACRO-NAME, and where it was defined.
2241 Most compilers don't include information about macros in the debugging
2242 information by default. In GCC 3.1, for example, you need to compile
2243 your program with the options `-gdwarf-2 -g3'. If the macro
2244 information is present in the executable, GDB will read it.
2246 * Multi-arched targets.
2248 DEC Alpha (partial) alpha*-*-*
2249 DEC VAX (partial) vax-*-*
2251 National Semiconductor NS32000 (partial) ns32k-*-*
2252 Motorola 68000 (partial) m68k-*-*
2253 Motorola MCORE mcore-*-*
2257 Fujitsu FRV architecture added by Red Hat frv*-*-*
2260 * New native configurations
2262 Alpha NetBSD alpha*-*-netbsd*
2263 SH NetBSD sh*-*-netbsdelf*
2264 MIPS NetBSD mips*-*-netbsd*
2265 UltraSPARC NetBSD sparc64-*-netbsd*
2267 * OBSOLETE configurations and files
2269 Configurations that have been declared obsolete in this release have
2270 been commented out. Unless there is activity to revive these
2271 configurations, the next release of GDB will have their sources
2272 permanently REMOVED.
2274 Mitsubishi D30V d30v-*-*
2275 OS/9000 i[34]86-*-os9k
2276 IBM AIX PS/2 i[3456]86-*-aix
2277 Fujitsu FR30 fr30-*-elf*
2278 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2279 Argonaut Risc Chip (ARC) arc-*-*
2280 i386 running Mach 3.0 i[3456]86-*-mach3*
2281 i386 running Mach i[3456]86-*-mach*
2282 i386 running OSF/1 i[3456]86-*osf1mk*
2283 HP/Apollo 68k Family m68*-apollo*-sysv*,
2285 m68*-hp-bsd*, m68*-hp-hpux*
2286 I960 with MON960 i960-*-coff
2288 * OBSOLETE languages
2290 CHILL, a Pascal like language used by telecommunications companies.
2292 * REMOVED configurations and files
2294 AMD 29k family via UDI a29k-amd-udi, udi29k
2295 A29K VxWorks a29k-*-vxworks
2296 AMD 29000 embedded, using EBMON a29k-none-none
2297 AMD 29000 embedded with COFF a29k-none-coff
2298 AMD 29000 embedded with a.out a29k-none-aout
2300 testsuite/gdb.hp/gdb.threads-hp/ directory
2302 * New command "set max-user-call-depth <nnn>"
2304 This command allows the user to limit the call depth of user-defined
2305 commands. The default is 1024.
2307 * Changes in FreeBSD/i386 native debugging.
2309 Support for the "generate-core-file" has been added.
2311 * New commands "dump", "append", and "restore".
2313 These commands allow data to be copied from target memory
2314 to a bfd-format or binary file (dump and append), and back
2315 from a file into memory (restore).
2317 * Improved "next/step" support on multi-processor Alpha Tru64.
2319 The previous single-step mechanism could cause unpredictable problems,
2320 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2321 of a software single-step mechanism prevents this.
2323 *** Changes in GDB 5.2.1:
2331 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2332 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2333 Fix, by Joel Brobecker imported from mainline.
2335 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2336 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2337 Fix, by Fred Fish, imported from mainline.
2339 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2340 Surprisingly enough, it works now.
2341 By Michal Ludvig, imported from mainline.
2343 i386 hardware watchpoint support:
2344 avoid misses on second run for some targets.
2345 By Pierre Muller, imported from mainline.
2347 *** Changes in GDB 5.2:
2349 * New command "set trust-readonly-sections on[off]".
2351 This command is a hint that tells gdb that read-only sections
2352 really are read-only (ie. that their contents will not change).
2353 In this mode, gdb will go to the object file rather than the
2354 target to read memory from read-only sections (such as ".text").
2355 This can be a significant performance improvement on some
2356 (notably embedded) targets.
2358 * New command "generate-core-file" (or "gcore").
2360 This new gdb command allows the user to drop a core file of the child
2361 process state at any time. So far it's been implemented only for
2362 GNU/Linux and Solaris, but should be relatively easily ported to other
2363 hosts. Argument is core file name (defaults to core.<pid>).
2365 * New command line option
2367 GDB now accepts --pid or -p followed by a process id.
2369 * Change in command line behavior -- corefiles vs. process ids.
2371 There is a subtle behavior in the way in which GDB handles
2372 command line arguments. The first non-flag argument is always
2373 a program to debug, but the second non-flag argument may either
2374 be a corefile or a process id. Previously, GDB would attempt to
2375 open the second argument as a corefile, and if that failed, would
2376 issue a superfluous error message and then attempt to attach it as
2377 a process. Now, if the second argument begins with a non-digit,
2378 it will be treated as a corefile. If it begins with a digit,
2379 GDB will attempt to attach it as a process, and if no such process
2380 is found, will then attempt to open it as a corefile.
2382 * Changes in ARM configurations.
2384 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2385 configuration is fully multi-arch.
2387 * New native configurations
2389 ARM NetBSD arm*-*-netbsd*
2390 x86 OpenBSD i[3456]86-*-openbsd*
2391 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2392 Sparc64 running FreeBSD sparc64-*-freebsd*
2396 Sanyo XStormy16 xstormy16-elf
2398 * OBSOLETE configurations and files
2400 Configurations that have been declared obsolete in this release have
2401 been commented out. Unless there is activity to revive these
2402 configurations, the next release of GDB will have their sources
2403 permanently REMOVED.
2405 AMD 29k family via UDI a29k-amd-udi, udi29k
2406 A29K VxWorks a29k-*-vxworks
2407 AMD 29000 embedded, using EBMON a29k-none-none
2408 AMD 29000 embedded with COFF a29k-none-coff
2409 AMD 29000 embedded with a.out a29k-none-aout
2411 testsuite/gdb.hp/gdb.threads-hp/ directory
2413 * REMOVED configurations and files
2415 TI TMS320C80 tic80-*-*
2417 PowerPC Solaris powerpcle-*-solaris*
2418 PowerPC Windows NT powerpcle-*-cygwin32
2419 PowerPC Netware powerpc-*-netware*
2420 Harris/CXUX m88k m88*-harris-cxux*
2421 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2422 ns32k-utek-sysv* ns32k-utek-*
2423 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2424 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2425 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2426 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2427 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2429 * Changes to command line processing
2431 The new `--args' feature can be used to specify command-line arguments
2432 for the inferior from gdb's command line.
2434 * Changes to key bindings
2436 There is a new `operate-and-get-next' function bound to `C-o'.
2438 *** Changes in GDB 5.1.1
2440 Fix compile problem on DJGPP.
2442 Fix a problem with floating-point registers on the i386 being
2445 Fix to stop GDB crashing on .debug_str debug info.
2447 Numerous documentation fixes.
2449 Numerous testsuite fixes.
2451 *** Changes in GDB 5.1:
2453 * New native configurations
2455 Alpha FreeBSD alpha*-*-freebsd*
2456 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2457 MIPS GNU/Linux mips*-*-linux*
2458 MIPS SGI Irix 6.x mips*-sgi-irix6*
2459 ia64 AIX ia64-*-aix*
2460 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2464 Motorola 68HC11 and 68HC12 m68hc11-elf
2466 UltraSparc running GNU/Linux sparc64-*-linux*
2468 * OBSOLETE configurations and files
2470 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2471 Harris/CXUX m88k m88*-harris-cxux*
2472 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2473 ns32k-utek-sysv* ns32k-utek-*
2474 TI TMS320C80 tic80-*-*
2476 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2477 PowerPC Solaris powerpcle-*-solaris*
2478 PowerPC Windows NT powerpcle-*-cygwin32
2479 PowerPC Netware powerpc-*-netware*
2480 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2481 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2482 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2483 Apple Macintosh (MPW) host N/A
2485 stuff.c (Program to stuff files into a specially prepared space in kdb)
2486 kdb-start.c (Main loop for the standalone kernel debugger)
2488 Configurations that have been declared obsolete in this release have
2489 been commented out. Unless there is activity to revive these
2490 configurations, the next release of GDB will have their sources
2491 permanently REMOVED.
2493 * REMOVED configurations and files
2495 Altos 3068 m68*-altos-*
2496 Convex c1-*-*, c2-*-*
2498 ARM RISCix arm-*-* (as host)
2502 * GDB has been converted to ISO C.
2504 GDB's source code has been converted to ISO C. In particular, the
2505 sources are fully protoized, and rely on standard headers being
2510 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2512 * The MI enabled by default.
2514 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2515 revised and enabled by default. Packages which use GDB as a debugging
2516 engine behind a UI or another front end are encouraged to switch to
2517 using the GDB/MI interface, instead of the old annotations interface
2518 which is now deprecated.
2520 * Support for debugging Pascal programs.
2522 GDB now includes support for debugging Pascal programs. The following
2523 main features are supported:
2525 - Pascal-specific data types such as sets;
2527 - automatic recognition of Pascal sources based on file-name
2530 - Pascal-style display of data types, variables, and functions;
2532 - a Pascal expression parser.
2534 However, some important features are not yet supported.
2536 - Pascal string operations are not supported at all;
2538 - there are some problems with boolean types;
2540 - Pascal type hexadecimal constants are not supported
2541 because they conflict with the internal variables format;
2543 - support for Pascal objects and classes is not full yet;
2545 - unlike Pascal, GDB is case-sensitive for symbol names.
2547 * Changes in completion.
2549 Commands such as `shell', `run' and `set args', which pass arguments
2550 to inferior programs, now complete on file names, similar to what
2551 users expect at the shell prompt.
2553 Commands which accept locations, such as `disassemble', `print',
2554 `breakpoint', `until', etc. now complete on filenames as well as
2555 program symbols. Thus, if you type "break foob TAB", and the source
2556 files linked into the programs include `foobar.c', that file name will
2557 be one of the candidates for completion. However, file names are not
2558 considered for completion after you typed a colon that delimits a file
2559 name from a name of a function in that file, as in "break foo.c:bar".
2561 `set demangle-style' completes on available demangling styles.
2563 * New platform-independent commands:
2565 It is now possible to define a post-hook for a command as well as a
2566 hook that runs before the command. For more details, see the
2567 documentation of `hookpost' in the GDB manual.
2569 * Changes in GNU/Linux native debugging.
2571 Support for debugging multi-threaded programs has been completely
2572 revised for all platforms except m68k and sparc. You can now debug as
2573 many threads as your system allows you to have.
2575 Attach/detach is supported for multi-threaded programs.
2577 Support for SSE registers was added for x86. This doesn't work for
2578 multi-threaded programs though.
2580 * Changes in MIPS configurations.
2582 Multi-arch support is enabled for all MIPS configurations.
2584 GDB can now be built as native debugger on SGI Irix 6.x systems for
2585 debugging n32 executables. (Debugging 64-bit executables is not yet
2588 * Unified support for hardware watchpoints in all x86 configurations.
2590 Most (if not all) native x86 configurations support hardware-assisted
2591 breakpoints and watchpoints in a unified manner. This support
2592 implements debug register sharing between watchpoints, which allows to
2593 put a virtually infinite number of watchpoints on the same address,
2594 and also supports watching regions up to 16 bytes with several debug
2597 The new maintenance command `maintenance show-debug-regs' toggles
2598 debugging print-outs in functions that insert, remove, and test
2599 watchpoints and hardware breakpoints.
2601 * Changes in the DJGPP native configuration.
2603 New command ``info dos sysinfo'' displays assorted information about
2604 the CPU, OS, memory, and DPMI server.
2606 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2607 display information about segment descriptors stored in GDT, LDT, and
2610 New commands ``info dos pde'' and ``info dos pte'' display entries
2611 from Page Directory and Page Tables (for now works with CWSDPMI only).
2612 New command ``info dos address-pte'' displays the Page Table entry for
2613 a given linear address.
2615 GDB can now pass command lines longer than 126 characters to the
2616 program being debugged (requires an update to the libdbg.a library
2617 which is part of the DJGPP development kit).
2619 DWARF2 debug info is now supported.
2621 It is now possible to `step' and `next' through calls to `longjmp'.
2623 * Changes in documentation.
2625 All GDB documentation was converted to GFDL, the GNU Free
2626 Documentation License.
2628 Tracepoints-related commands are now fully documented in the GDB
2631 TUI, the Text-mode User Interface, is now documented in the manual.
2633 Tracepoints-related commands are now fully documented in the GDB
2636 The "GDB Internals" manual now has an index. It also includes
2637 documentation of `ui_out' functions, GDB coding standards, x86
2638 hardware watchpoints, and memory region attributes.
2640 * GDB's version number moved to ``version.in''
2642 The Makefile variable VERSION has been replaced by the file
2643 ``version.in''. People creating GDB distributions should update the
2644 contents of this file.
2648 GUD support is now a standard part of the EMACS distribution.
2650 *** Changes in GDB 5.0:
2652 * Improved support for debugging FP programs on x86 targets
2654 Unified and much-improved support for debugging floating-point
2655 programs on all x86 targets. In particular, ``info float'' now
2656 displays the FP registers in the same format on all x86 targets, with
2657 greater level of detail.
2659 * Improvements and bugfixes in hardware-assisted watchpoints
2661 It is now possible to watch array elements, struct members, and
2662 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2663 on x86 targets no longer erroneously trigger when the address is
2666 * Improvements in the native DJGPP version of GDB
2668 The distribution now includes all the scripts and auxiliary files
2669 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2670 machines ``out of the box''.
2672 The DJGPP version can now debug programs that use signals. It is
2673 possible to catch signals that happened in the debuggee, deliver
2674 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2675 would kill the program being debugged.) Programs that hook hardware
2676 interrupts (keyboard, timer, etc.) can also be debugged.
2678 It is now possible to debug DJGPP programs that redirect their
2679 standard handles or switch them to raw (as opposed to cooked) mode, or
2680 even close them. The command ``run < foo > bar'' works as expected,
2681 and ``info terminal'' reports useful information about the debuggee's
2682 terminal, including raw/cooked mode, redirection, etc.
2684 The DJGPP version now uses termios functions for console I/O, which
2685 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2688 DOS-style file names with drive letters are now fully supported by
2691 It is now possible to debug DJGPP programs that switch their working
2692 directory. It is also possible to rerun the debuggee any number of
2693 times without restarting GDB; thus, you can use the same setup,
2694 breakpoints, etc. for many debugging sessions.
2696 * New native configurations
2698 ARM GNU/Linux arm*-*-linux*
2699 PowerPC GNU/Linux powerpc-*-linux*
2703 Motorola MCore mcore-*-*
2704 x86 VxWorks i[3456]86-*-vxworks*
2705 PowerPC VxWorks powerpc-*-vxworks*
2706 TI TMS320C80 tic80-*-*
2708 * OBSOLETE configurations
2710 Altos 3068 m68*-altos-*
2711 Convex c1-*-*, c2-*-*
2713 ARM RISCix arm-*-* (as host)
2716 Configurations that have been declared obsolete will be commented out,
2717 but the code will be left in place. If there is no activity to revive
2718 these configurations before the next release of GDB, the sources will
2719 be permanently REMOVED.
2721 * Gould support removed
2723 Support for the Gould PowerNode and NP1 has been removed.
2725 * New features for SVR4
2727 On SVR4 native platforms (such as Solaris), if you attach to a process
2728 without first loading a symbol file, GDB will now attempt to locate and
2729 load symbols from the running process's executable file.
2731 * Many C++ enhancements
2733 C++ support has been greatly improved. Overload resolution now works properly
2734 in almost all cases. RTTI support is on the way.
2736 * Remote targets can connect to a sub-program
2738 A popen(3) style serial-device has been added. This device starts a
2739 sub-process (such as a stand-alone simulator) and then communicates
2740 with that. The sub-program to run is specified using the syntax
2741 ``|<program> <args>'' vis:
2743 (gdb) set remotedebug 1
2744 (gdb) target extended-remote |mn10300-elf-sim program-args
2746 * MIPS 64 remote protocol
2748 A long standing bug in the mips64 remote protocol where by GDB
2749 expected certain 32 bit registers (ex SR) to be transfered as 32
2750 instead of 64 bits has been fixed.
2752 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2753 added to provide backward compatibility with older versions of GDB.
2755 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2757 The command ``set remotebinarydownload'' command has been replaced by
2758 ``set remote X-packet''. Other commands in ``set remote'' family
2759 include ``set remote P-packet''.
2761 * Breakpoint commands accept ranges.
2763 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2764 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2765 ``tracepoint passcount'' also accepts a range of tracepoints.
2767 * ``apropos'' command added.
2769 The ``apropos'' command searches through command names and
2770 documentation strings, printing out matches, making it much easier to
2771 try to find a command that does what you are looking for.
2775 A new machine oriented interface (MI) has been added to GDB. This
2776 interface is designed for debug environments running GDB as a separate
2777 process. This is part of the long term libGDB project. See the
2778 "GDB/MI" chapter of the GDB manual for further information. It can be
2779 enabled by configuring with:
2781 .../configure --enable-gdbmi
2783 *** Changes in GDB-4.18:
2785 * New native configurations
2787 HP-UX 10.20 hppa*-*-hpux10.20
2788 HP-UX 11.x hppa*-*-hpux11.0*
2789 M68K GNU/Linux m68*-*-linux*
2793 Fujitsu FR30 fr30-*-elf*
2794 Intel StrongARM strongarm-*-*
2795 Mitsubishi D30V d30v-*-*
2797 * OBSOLETE configurations
2799 Gould PowerNode, NP1 np1-*-*, pn-*-*
2801 Configurations that have been declared obsolete will be commented out,
2802 but the code will be left in place. If there is no activity to revive
2803 these configurations before the next release of GDB, the sources will
2804 be permanently REMOVED.
2808 As a compatibility experiment, GDB's source files buildsym.h and
2809 buildsym.c have been converted to pure standard C, no longer
2810 containing any K&R compatibility code. We believe that all systems in
2811 use today either come with a standard C compiler, or have a GCC port
2812 available. If this is not true, please report the affected
2813 configuration to bug-gdb@gnu.org immediately. See the README file for
2814 information about getting a standard C compiler if you don't have one
2819 GDB now uses readline 2.2.
2821 * set extension-language
2823 You can now control the mapping between filename extensions and source
2824 languages by using the `set extension-language' command. For instance,
2825 you can ask GDB to treat .c files as C++ by saying
2826 set extension-language .c c++
2827 The command `info extensions' lists all of the recognized extensions
2828 and their associated languages.
2830 * Setting processor type for PowerPC and RS/6000
2832 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2833 you can use the `set processor' command to specify what variant of the
2834 PowerPC family you are debugging. The command
2838 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2839 following PowerPC and RS6000 variants:
2841 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2842 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2844 403GC IBM PowerPC 403GC
2845 505 Motorola PowerPC 505
2846 860 Motorola PowerPC 860 or 850
2847 601 Motorola PowerPC 601
2848 602 Motorola PowerPC 602
2849 603 Motorola/IBM PowerPC 603 or 603e
2850 604 Motorola PowerPC 604 or 604e
2851 750 Motorola/IBM PowerPC 750 or 750
2853 At the moment, this command just tells GDB what to name the
2854 special-purpose processor registers. Since almost all the affected
2855 registers are inaccessible to user-level programs, this command is
2856 only useful for remote debugging in its present form.
2860 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2861 more extensive support for HP-UX. Added features include shared
2862 library support, kernel threads and hardware watchpoints for 11.00,
2863 support for HP's ANSI C and C++ compilers, and a compatibility mode
2864 for xdb and dbx commands.
2868 HP's donation includes the new concept of catchpoints, which is a
2869 generalization of the old catch command. On HP-UX, it is now possible
2870 to catch exec, fork, and vfork, as well as library loading.
2872 This means that the existing catch command has changed; its first
2873 argument now specifies the type of catch to be set up. See the
2874 output of "help catch" for a list of catchpoint types.
2876 * Debugging across forks
2878 On HP-UX, you can choose which process to debug when a fork() happens
2883 HP has donated a curses-based terminal user interface (TUI). To get
2884 it, build with --enable-tui. Although this can be enabled for any
2885 configuration, at present it only works for native HP debugging.
2887 * GDB remote protocol additions
2889 A new protocol packet 'X' that writes binary data is now available.
2890 Default behavior is to try 'X', then drop back to 'M' if the stub
2891 fails to respond. The settable variable `remotebinarydownload'
2892 allows explicit control over the use of 'X'.
2894 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2895 full 64-bit address. The command
2897 set remoteaddresssize 32
2899 can be used to revert to the old behaviour. For existing remote stubs
2900 the change should not be noticed, as the additional address information
2903 In order to assist in debugging stubs, you may use the maintenance
2904 command `packet' to send any text string to the stub. For instance,
2906 maint packet heythere
2908 sends the packet "$heythere#<checksum>". Note that it is very easy to
2909 disrupt a debugging session by sending the wrong packet at the wrong
2912 The compare-sections command allows you to compare section data on the
2913 target to what is in the executable file without uploading or
2914 downloading, by comparing CRC checksums.
2916 * Tracing can collect general expressions
2918 You may now collect general expressions at tracepoints. This requires
2919 further additions to the target-side stub; see tracepoint.c and
2920 doc/agentexpr.texi for further details.
2922 * mask-address variable for Mips
2924 For Mips targets, you may control the zeroing of the upper 32 bits of
2925 a 64-bit address by entering `set mask-address on'. This is mainly
2926 of interest to users of embedded R4xxx and R5xxx processors.
2928 * Higher serial baud rates
2930 GDB's serial code now allows you to specify baud rates 57600, 115200,
2931 230400, and 460800 baud. (Note that your host system may not be able
2932 to achieve all of these rates.)
2936 The i960 configuration now includes an initial implementation of a
2937 builtin simulator, contributed by Jim Wilson.
2940 *** Changes in GDB-4.17:
2942 * New native configurations
2944 Alpha GNU/Linux alpha*-*-linux*
2945 Unixware 2.x i[3456]86-unixware2*
2946 Irix 6.x mips*-sgi-irix6*
2947 PowerPC GNU/Linux powerpc-*-linux*
2948 PowerPC Solaris powerpcle-*-solaris*
2949 Sparc GNU/Linux sparc-*-linux*
2950 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2954 Argonaut Risc Chip (ARC) arc-*-*
2955 Hitachi H8/300S h8300*-*-*
2956 Matsushita MN10200 w/simulator mn10200-*-*
2957 Matsushita MN10300 w/simulator mn10300-*-*
2958 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2959 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2960 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2961 Mitsubishi D10V w/simulator d10v-*-*
2962 Mitsubishi M32R/D w/simulator m32r-*-elf*
2963 Tsqware Sparclet sparclet-*-*
2964 NEC V850 w/simulator v850-*-*
2966 * New debugging protocols
2968 ARM with RDI protocol arm*-*-*
2969 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2970 DDB and LSI variants of PMON protocol mips*-*-*
2971 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2972 PowerPC with SDS protocol powerpc{,le}-*-eabi
2973 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2977 All configurations can now understand and use the DWARF 2 debugging
2978 format. The choice is automatic, if the symbol file contains DWARF 2
2983 GDB now includes basic Java language support. This support is
2984 only useful with Java compilers that produce native machine code.
2986 * solib-absolute-prefix and solib-search-path
2988 For SunOS and SVR4 shared libraries, you may now set the prefix for
2989 loading absolute shared library symbol files, and the search path for
2990 locating non-absolute shared library symbol files.
2992 * Live range splitting
2994 GDB can now effectively debug code for which GCC has performed live
2995 range splitting as part of its optimization. See gdb/doc/LRS for
2996 more details on the expected format of the stabs information.
3000 GDB's support for the GNU Hurd, including thread debugging, has been
3001 updated to work with current versions of the Hurd.
3005 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3006 instruction set. ARM GDB automatically detects when Thumb
3007 instructions are in use, and adjusts disassembly and backtracing
3012 GDB's MIPS target configurations now handle the MIP16 16-bit
3017 GDB now includes support for overlays; if an executable has been
3018 linked such that multiple sections are based at the same address, GDB
3019 will decide which section to use for symbolic info. You can choose to
3020 control the decision manually, using overlay commands, or implement
3021 additional target-side support and use "overlay load-target" to bring
3022 in the overlay mapping. Do "help overlay" for more detail.
3026 The command "info symbol <address>" displays information about
3027 the symbol at the specified address.
3031 The standard remote protocol now includes an extension that allows
3032 asynchronous collection and display of trace data. This requires
3033 extensive support in the target-side debugging stub. Tracing mode
3034 includes a new interaction mode in GDB and new commands: see the
3035 file tracepoint.c for more details.
3039 Configurations for embedded MIPS now include a simulator contributed
3040 by Cygnus Solutions. The simulator supports the instruction sets
3041 of most MIPS variants.
3045 Sparc configurations may now include the ERC32 simulator contributed
3046 by the European Space Agency. The simulator is not built into
3047 Sparc targets by default; configure with --enable-sim to include it.
3051 For target configurations that may include multiple variants of a
3052 basic architecture (such as MIPS and SH), you may now set the
3053 architecture explicitly. "set arch" sets, "info arch" lists
3054 the possible architectures.
3056 *** Changes in GDB-4.16:
3058 * New native configurations
3060 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3061 M68K NetBSD m68k-*-netbsd*
3062 PowerPC AIX 4.x powerpc-*-aix*
3063 PowerPC MacOS powerpc-*-macos*
3064 PowerPC Windows NT powerpcle-*-cygwin32
3065 RS/6000 AIX 4.x rs6000-*-aix4*
3069 ARM with RDP protocol arm-*-*
3070 I960 with MON960 i960-*-coff
3071 MIPS VxWorks mips*-*-vxworks*
3072 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3073 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3075 Matra Sparclet sparclet-*-*
3079 The powerpc-eabi configuration now includes the PSIM simulator,
3080 contributed by Andrew Cagney, with assistance from Mike Meissner.
3081 PSIM is a very elaborate model of the PowerPC, including not only
3082 basic instruction set execution, but also details of execution unit
3083 performance and I/O hardware. See sim/ppc/README for more details.
3087 GDB now works with Solaris 2.5.
3089 * Windows 95/NT native
3091 GDB will now work as a native debugger on Windows 95 and Windows NT.
3092 To build it from source, you must use the "gnu-win32" environment,
3093 which uses a DLL to emulate enough of Unix to run the GNU tools.
3094 Further information, binaries, and sources are available at
3095 ftp.cygnus.com, under pub/gnu-win32.
3097 * dont-repeat command
3099 If a user-defined command includes the command `dont-repeat', then the
3100 command will not be repeated if the user just types return. This is
3101 useful if the command is time-consuming to run, so that accidental
3102 extra keystrokes don't run the same command many times.
3104 * Send break instead of ^C
3106 The standard remote protocol now includes an option to send a break
3107 rather than a ^C to the target in order to interrupt it. By default,
3108 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3110 * Remote protocol timeout
3112 The standard remote protocol includes a new variable `remotetimeout'
3113 that allows you to set the number of seconds before GDB gives up trying
3114 to read from the target. The default value is 2.
3116 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3118 By default GDB will automatically keep track of objects as they are
3119 loaded and unloaded by the dynamic linker. By using the command `set
3120 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3121 when shared library events occur, thus allowing you to set breakpoints
3122 in shared libraries which are explicitly loaded by the inferior.
3124 Note this feature does not work on hpux8. On hpux9 you must link
3125 /usr/lib/end.o into your program. This feature should work
3126 automatically on hpux10.
3128 * Irix 5.x hardware watchpoint support
3130 Irix 5 configurations now support the use of hardware watchpoints.
3132 * Mips protocol "SYN garbage limit"
3134 When debugging a Mips target using the `target mips' protocol, you
3135 may set the number of characters that GDB will ignore by setting
3136 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3137 every character. The default value is 1050.
3139 * Recording and replaying remote debug sessions
3141 If you set `remotelogfile' to the name of a file, gdb will write to it
3142 a recording of a remote debug session. This recording may then be
3143 replayed back to gdb using "gdbreplay". See gdbserver/README for
3144 details. This is useful when you have a problem with GDB while doing
3145 remote debugging; you can make a recording of the session and send it
3146 to someone else, who can then recreate the problem.
3148 * Speedups for remote debugging
3150 GDB includes speedups for downloading and stepping MIPS systems using
3151 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3152 and more efficient S-record downloading.
3154 * Memory use reductions and statistics collection
3156 GDB now uses less memory and reports statistics about memory usage.
3157 Try the `maint print statistics' command, for example.
3159 *** Changes in GDB-4.15:
3161 * Psymtabs for XCOFF
3163 The symbol reader for AIX GDB now uses partial symbol tables. This
3164 can greatly improve startup time, especially for large executables.
3166 * Remote targets use caching
3168 Remote targets now use a data cache to speed up communication with the
3169 remote side. The data cache could lead to incorrect results because
3170 it doesn't know about volatile variables, thus making it impossible to
3171 debug targets which use memory mapped I/O devices. `set remotecache
3172 off' turns the the data cache off.
3174 * Remote targets may have threads
3176 The standard remote protocol now includes support for multiple threads
3177 in the target system, using new protocol commands 'H' and 'T'. See
3178 gdb/remote.c for details.
3182 If GDB is configured with `--enable-netrom', then it will include
3183 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3184 acts as though it is a bank of ROM on the target board, but you can
3185 write into it over the network. GDB's support consists only of
3186 support for fast loading into the emulated ROM; to debug, you must use
3187 another protocol, such as standard remote protocol. The usual
3188 sequence is something like
3190 target nrom <netrom-hostname>
3192 target remote <netrom-hostname>:1235
3196 GDB now includes support for the Apple Macintosh, as a host only. It
3197 may be run as either an MPW tool or as a standalone application, and
3198 it can debug through the serial port. All the usual GDB commands are
3199 available, but to the target command, you must supply "serial" as the
3200 device type instead of "/dev/ttyXX". See mpw-README in the main
3201 directory for more information on how to build. The MPW configuration
3202 scripts */mpw-config.in support only a few targets, and only the
3203 mips-idt-ecoff target has been tested.
3207 GDB configuration now uses autoconf. This is not user-visible,
3208 but does simplify configuration and building.
3212 GDB now supports hpux10.
3214 *** Changes in GDB-4.14:
3216 * New native configurations
3218 x86 FreeBSD i[345]86-*-freebsd
3219 x86 NetBSD i[345]86-*-netbsd
3220 NS32k NetBSD ns32k-*-netbsd
3221 Sparc NetBSD sparc-*-netbsd
3225 A29K VxWorks a29k-*-vxworks
3226 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3227 CPU32 EST-300 emulator m68*-*-est*
3228 PowerPC ELF powerpc-*-elf
3231 * Alpha OSF/1 support for procfs
3233 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3234 possible to attach to running processes. As the mounting of the /proc
3235 filesystem is optional on the Alpha, GDB automatically determines
3236 the availability of /proc during startup. This can lead to problems
3237 if /proc is unmounted after GDB has been started.
3239 * Arguments to user-defined commands
3241 User commands may accept up to 10 arguments separated by whitespace.
3242 Arguments are accessed within the user command via $arg0..$arg9. A
3245 print $arg0 + $arg1 + $arg2
3247 To execute the command use:
3250 Defines the command "adder" which prints the sum of its three arguments.
3251 Note the arguments are text substitutions, so they may reference variables,
3252 use complex expressions, or even perform inferior function calls.
3254 * New `if' and `while' commands
3256 This makes it possible to write more sophisticated user-defined
3257 commands. Both commands take a single argument, which is the
3258 expression to evaluate, and must be followed by the commands to
3259 execute, one per line, if the expression is nonzero, the list being
3260 terminated by the word `end'. The `if' command list may include an
3261 `else' word, which causes the following commands to be executed only
3262 if the expression is zero.
3264 * Fortran source language mode
3266 GDB now includes partial support for Fortran 77. It will recognize
3267 Fortran programs and can evaluate a subset of Fortran expressions, but
3268 variables and functions may not be handled correctly. GDB will work
3269 with G77, but does not yet know much about symbols emitted by other
3272 * Better HPUX support
3274 Most debugging facilities now work on dynamic executables for HPPAs
3275 running hpux9 or later. You can attach to running dynamically linked
3276 processes, but by default the dynamic libraries will be read-only, so
3277 for instance you won't be able to put breakpoints in them. To change
3278 that behavior do the following before running the program:
3284 This will cause the libraries to be mapped private and read-write.
3285 To revert to the normal behavior, do this:
3291 You cannot set breakpoints or examine data in the library until after
3292 the library is loaded if the function/data symbols do not have
3295 GDB can now also read debug symbols produced by the HP C compiler on
3296 HPPAs (sorry, no C++, Fortran or 68k support).
3298 * Target byte order now dynamically selectable
3300 You can choose which byte order to use with a target system, via the
3301 commands "set endian big" and "set endian little", and you can see the
3302 current setting by using "show endian". You can also give the command
3303 "set endian auto", in which case GDB will use the byte order
3304 associated with the executable. Currently, only embedded MIPS
3305 configurations support dynamic selection of target byte order.
3307 * New DOS host serial code
3309 This version uses DPMI interrupts to handle buffered I/O, so you
3310 no longer need to run asynctsr when debugging boards connected to
3313 *** Changes in GDB-4.13:
3315 * New "complete" command
3317 This lists all the possible completions for the rest of the line, if it
3318 were to be given as a command itself. This is intended for use by emacs.
3320 * Trailing space optional in prompt
3322 "set prompt" no longer adds a space for you after the prompt you set. This
3323 allows you to set a prompt which ends in a space or one that does not.
3325 * Breakpoint hit counts
3327 "info break" now displays a count of the number of times the breakpoint
3328 has been hit. This is especially useful in conjunction with "ignore"; you
3329 can ignore a large number of breakpoint hits, look at the breakpoint info
3330 to see how many times the breakpoint was hit, then run again, ignoring one
3331 less than that number, and this will get you quickly to the last hit of
3334 * Ability to stop printing at NULL character
3336 "set print null-stop" will cause GDB to stop printing the characters of
3337 an array when the first NULL is encountered. This is useful when large
3338 arrays actually contain only short strings.
3340 * Shared library breakpoints
3342 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3343 breakpoints in shared libraries before the executable is run.
3345 * Hardware watchpoints
3347 There is a new hardware breakpoint for the watch command for sparclite
3348 targets. See gdb/sparclite/hw_breakpoint.note.
3350 Hardware watchpoints are also now supported under GNU/Linux.
3354 Annotations have been added. These are for use with graphical interfaces,
3355 and are still experimental. Currently only gdba.el uses these.
3357 * Improved Irix 5 support
3359 GDB now works properly with Irix 5.2.
3361 * Improved HPPA support
3363 GDB now works properly with the latest GCC and GAS.
3365 * New native configurations
3367 Sequent PTX4 i[34]86-sequent-ptx4
3368 HPPA running OSF/1 hppa*-*-osf*
3369 Atari TT running SVR4 m68*-*-sysv4*
3370 RS/6000 LynxOS rs6000-*-lynxos*
3374 OS/9000 i[34]86-*-os9k
3375 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3378 * Hitachi SH7000 and E7000-PC ICE support
3380 There is now support for communicating with the Hitachi E7000-PC ICE.
3381 This is available automatically when GDB is configured for the SH.
3385 As usual, a variety of small fixes and improvements, both generic
3386 and configuration-specific. See the ChangeLog for more detail.
3388 *** Changes in GDB-4.12:
3390 * Irix 5 is now supported
3394 GDB-4.12 on the HPPA has a number of changes which make it unable
3395 to debug the output from the currently released versions of GCC and
3396 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3397 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3398 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3401 *** Changes in GDB-4.11:
3403 * User visible changes:
3407 The "set remotedebug" option is now consistent between the mips remote
3408 target, remote targets using the gdb-specific protocol, UDI (AMD's
3409 debug protocol for the 29k) and the 88k bug monitor. It is now an
3410 integer specifying a debug level (normally 0 or 1, but 2 means more
3411 debugging info for the mips target).
3413 * DEC Alpha native support
3415 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3416 debug info, but GDB works fairly well with the DEC compiler and should
3417 work with a future GCC release. See the README file for a few
3418 Alpha-specific notes.
3420 * Preliminary thread implementation
3422 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3424 * LynxOS native and target support for 386
3426 This release has been hosted on LynxOS 2.2, and also can be configured
3427 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3430 * Improvements in C++ mangling/demangling.
3432 This release has much better g++ debugging, specifically in name
3433 mangling/demangling, virtual function calls, print virtual table,
3434 call methods, ...etc.
3436 *** Changes in GDB-4.10:
3438 * User visible changes:
3440 Remote debugging using the GDB-specific (`target remote') protocol now
3441 supports the `load' command. This is only useful if you have some
3442 other way of getting the stub to the target system, and you can put it
3443 somewhere in memory where it won't get clobbered by the download.
3445 Filename completion now works.
3447 When run under emacs mode, the "info line" command now causes the
3448 arrow to point to the line specified. Also, "info line" prints
3449 addresses in symbolic form (as well as hex).
3451 All vxworks based targets now support a user settable option, called
3452 vxworks-timeout. This option represents the number of seconds gdb
3453 should wait for responses to rpc's. You might want to use this if
3454 your vxworks target is, perhaps, a slow software simulator or happens
3455 to be on the far side of a thin network line.
3459 This release contains support for using a DEC alpha as a GDB host for
3460 cross debugging. Native alpha debugging is not supported yet.
3463 *** Changes in GDB-4.9:
3467 This is the first GDB release which is accompanied by a matching testsuite.
3468 The testsuite requires installation of dejagnu, which should be available
3469 via ftp from most sites that carry GNU software.
3473 'Cfront' style demangling has had its name changed to 'ARM' style, to
3474 emphasize that it was written from the specifications in the C++ Annotated
3475 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3476 disclaimers, it still generated too much confusion with users attempting to
3477 use gdb with AT&T cfront.
3481 GDB now uses a standard remote interface to a simulator library.
3482 So far, the library contains simulators for the Zilog Z8001/2, the
3483 Hitachi H8/300, H8/500 and Super-H.
3485 * New targets supported
3487 H8/300 simulator h8300-hitachi-hms or h8300hms
3488 H8/500 simulator h8500-hitachi-hms or h8500hms
3489 SH simulator sh-hitachi-hms or sh
3490 Z8000 simulator z8k-zilog-none or z8ksim
3491 IDT MIPS board over serial line mips-idt-ecoff
3493 Cross-debugging to GO32 targets is supported. It requires a custom
3494 version of the i386-stub.c module which is integrated with the
3495 GO32 memory extender.
3497 * New remote protocols
3499 MIPS remote debugging protocol.
3501 * New source languages supported
3503 This version includes preliminary support for Chill, a Pascal like language
3504 used by telecommunications companies. Chill support is also being integrated
3505 into the GNU compiler, but we don't know when it will be publically available.
3508 *** Changes in GDB-4.8:
3510 * HP Precision Architecture supported
3512 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3513 version of this support was available as a set of patches from the
3514 University of Utah. GDB does not support debugging of programs
3515 compiled with the HP compiler, because HP will not document their file
3516 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3517 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3519 Many problems in the preliminary version have been fixed.
3521 * Faster and better demangling
3523 We have improved template demangling and fixed numerous bugs in the GNU style
3524 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3525 character types (wchar_t) are now supported. Demangling of each symbol is now
3526 only done once, and is cached when the symbol table for a file is read in.
3527 This results in a small increase in memory usage for C programs, a moderate
3528 increase in memory usage for C++ programs, and a fantastic speedup in
3531 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3532 from the specifications in the Annotated Reference Manual, which AT&T's
3533 compiler does not actually implement.
3535 * G++ multiple inheritance compiler problem
3537 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3538 inheritance lattices was reworked to properly discover ambiguities. We
3539 recently found an example which causes this new algorithm to fail in a
3540 very subtle way, producing bad debug information for those classes.
3541 The file 'gcc.patch' (in this directory) can be applied to gcc to
3542 circumvent the problem. A future GCC release will contain a complete
3545 The previous G++ debug info problem (mentioned below for the gdb-4.7
3546 release) is fixed in gcc version 2.3.2.
3548 * Improved configure script
3550 The `configure' script will now attempt to guess your system type if
3551 you don't supply a host system type. The old scheme of supplying a
3552 host system triplet is preferable over using this. All the magic is
3553 done in the new `config.guess' script. Examine it for details.
3555 We have also brought our configure script much more in line with the FSF's
3556 version. It now supports the --with-xxx options. In particular,
3557 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3558 The resulting GDB will not be able to read arbitrary object file formats --
3559 only the format ``expected'' to be used on the configured target system.
3560 We hope to make this the default in a future release.
3562 * Documentation improvements
3564 There's new internal documentation on how to modify GDB, and how to
3565 produce clean changes to the code. We implore people to read it
3566 before submitting changes.
3568 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3569 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3570 `info' files are also provided. To build `info' files from scratch,
3571 you will need the latest `makeinfo' release, which will be available in
3572 a future texinfo-X.Y release.
3574 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3575 We're not sure exactly which versions have this problem, but it has
3576 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3577 or better. If that isn't possible, there is a patch in
3578 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3579 around this problem.
3583 GDB now supports array constants that can be used in expressions typed in by
3584 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3585 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3588 The new directory `gdb/sparclite' contains a program that demonstrates
3589 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3591 * New native hosts supported
3593 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3594 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3596 * New targets supported
3598 AMD 29k family via UDI a29k-amd-udi or udi29k
3600 * New file formats supported
3602 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3603 HPUX core files, and SCO 3.2v2 core files.
3607 Attaching to processes now works again; thanks for the many bug reports.
3609 We have also stomped on a bunch of core dumps caused by
3610 printf_filtered("%s") problems.
3612 We eliminated a copyright problem on the rpc and ptrace header files
3613 for VxWorks, which was discovered at the last minute during the 4.7
3614 release. You should now be able to build a VxWorks GDB.
3616 You can now interrupt gdb while an attached process is running. This
3617 will cause the attached process to stop, and give control back to GDB.
3619 We fixed problems caused by using too many file descriptors
3620 for reading symbols from object files and libraries. This was
3621 especially a problem for programs that used many (~100) shared
3624 The `step' command now only enters a subroutine if there is line number
3625 information for the subroutine. Otherwise it acts like the `next'
3626 command. Previously, `step' would enter subroutines if there was
3627 any debugging information about the routine. This avoids problems
3628 when using `cc -g1' on MIPS machines.
3630 * Internal improvements
3632 GDB's internal interfaces have been improved to make it easier to support
3633 debugging of multiple languages in the future.
3635 GDB now uses a common structure for symbol information internally.
3636 Minimal symbols (derived from linkage symbols in object files), partial
3637 symbols (from a quick scan of debug information), and full symbols
3638 contain a common subset of information, making it easier to write
3639 shared code that handles any of them.
3641 * New command line options
3643 We now accept --silent as an alias for --quiet.
3647 The memory-mapped-malloc library is now licensed under the GNU Library
3648 General Public License.
3650 *** Changes in GDB-4.7:
3652 * Host/native/target split
3654 GDB has had some major internal surgery to untangle the support for
3655 hosts and remote targets. Now, when you configure GDB for a remote
3656 target, it will no longer load in all of the support for debugging
3657 local programs on the host. When fully completed and tested, this will
3658 ensure that arbitrary host/target combinations are possible.
3660 The primary conceptual shift is to separate the non-portable code in
3661 GDB into three categories. Host specific code is required any time GDB
3662 is compiled on that host, regardless of the target. Target specific
3663 code relates to the peculiarities of the target, but can be compiled on
3664 any host. Native specific code is everything else: it can only be
3665 built when the host and target are the same system. Child process
3666 handling and core file support are two common `native' examples.
3668 GDB's use of /proc for controlling Unix child processes is now cleaner.
3669 It has been split out into a single module under the `target_ops' vector,
3670 plus two native-dependent functions for each system that uses /proc.
3672 * New hosts supported
3674 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3675 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3676 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3678 * New targets supported
3680 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3681 68030 and CPU32 m68030-*-*, m68332-*-*
3683 * New native hosts supported
3685 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3686 (386bsd is not well tested yet)
3687 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3689 * New file formats supported
3691 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3692 supports reading of `a.out.adobe' object files, which are an a.out
3693 format extended with minimal information about multiple sections.
3697 `show copying' is the same as the old `info copying'.
3698 `show warranty' is the same as `info warrantee'.
3699 These were renamed for consistency. The old commands continue to work.
3701 `info handle' is a new alias for `info signals'.
3703 You can now define pre-command hooks, which attach arbitrary command
3704 scripts to any command. The commands in the hook will be executed
3705 prior to the user's command. You can also create a hook which will be
3706 executed whenever the program stops. See gdb.texinfo.
3710 We now deal with Cfront style name mangling, and can even extract type
3711 info from mangled symbols. GDB can automatically figure out which
3712 symbol mangling style your C++ compiler uses.
3714 Calling of methods and virtual functions has been improved as well.
3718 The crash that occured when debugging Sun Ansi-C compiled binaries is
3719 fixed. This was due to mishandling of the extra N_SO stabs output
3722 We also finally got Ultrix 4.2 running in house, and fixed core file
3723 support, with help from a dozen people on the net.
3725 John M. Farrell discovered that the reason that single-stepping was so
3726 slow on all of the Mips based platforms (primarily SGI and DEC) was
3727 that we were trying to demangle and lookup a symbol used for internal
3728 purposes on every instruction that was being stepped through. Changing
3729 the name of that symbol so that it couldn't be mistaken for a C++
3730 mangled symbol sped things up a great deal.
3732 Rich Pixley sped up symbol lookups in general by getting much smarter
3733 about when C++ symbol mangling is necessary. This should make symbol
3734 completion (TAB on the command line) much faster. It's not as fast as
3735 we'd like, but it's significantly faster than gdb-4.6.
3739 A new user controllable variable 'call_scratch_address' can
3740 specify the location of a scratch area to be used when GDB
3741 calls a function in the target. This is necessary because the
3742 usual method of putting the scratch area on the stack does not work
3743 in systems that have separate instruction and data spaces.
3745 We integrated changes to support the 29k UDI (Universal Debugger
3746 Interface), but discovered at the last minute that we didn't have all
3747 of the appropriate copyright paperwork. We are working with AMD to
3748 resolve this, and hope to have it available soon.
3752 We have sped up the remote serial line protocol, especially for targets
3753 with lots of registers. It now supports a new `expedited status' ('T')
3754 message which can be used in place of the existing 'S' status message.
3755 This allows the remote stub to send only the registers that GDB
3756 needs to make a quick decision about single-stepping or conditional
3757 breakpoints, eliminating the need to fetch the entire register set for
3758 each instruction being stepped through.
3760 The GDB remote serial protocol now implements a write-through cache for
3761 registers, only re-reading the registers if the target has run.
3763 There is also a new remote serial stub for SPARC processors. You can
3764 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3765 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3766 processor with a serial port.
3770 Configure.in files have become much easier to read and modify. A new
3771 `table driven' format makes it more obvious what configurations are
3772 supported, and what files each one uses.
3776 There is a new opcodes library which will eventually contain all of the
3777 disassembly routines and opcode tables. At present, it only contains
3778 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3779 disassembler (binutils/objdump) to share these routines.
3781 The libiberty library is now copylefted under the GNU Library General
3782 Public License. This allows more liberal use, and was done so libg++
3783 can use it. This makes no difference to GDB, since the Library License
3784 grants all the rights from the General Public License.
3788 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3789 reference to the stabs symbol info used by the debugger. It is (as far
3790 as we know) the only published document on this fascinating topic. We
3791 encourage you to read it, compare it to the stabs information on your
3792 system, and send improvements on the document in general (to
3793 bug-gdb@prep.ai.mit.edu).
3795 And, of course, many bugs have been fixed.
3798 *** Changes in GDB-4.6:
3800 * Better support for C++ function names
3802 GDB now accepts as input the "demangled form" of C++ overloaded function
3803 names and member function names, and can do command completion on such names
3804 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3805 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3806 Make use of command completion, it is your friend.
3808 GDB also now accepts a variety of C++ mangled symbol formats. They are
3809 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3810 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3811 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3812 for the list of formats.
3814 * G++ symbol mangling problem
3816 Recent versions of gcc have a bug in how they emit debugging information for
3817 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3818 directory) can be applied to gcc to fix the problem. Alternatively, if you
3819 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3820 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3821 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3824 * New 'maintenance' command
3826 All of the commands related to hacking GDB internals have been moved out of
3827 the main command set, and now live behind the 'maintenance' command. This
3828 can also be abbreviated as 'mt'. The following changes were made:
3830 dump-me -> maintenance dump-me
3831 info all-breakpoints -> maintenance info breakpoints
3832 printmsyms -> maintenance print msyms
3833 printobjfiles -> maintenance print objfiles
3834 printpsyms -> maintenance print psymbols
3835 printsyms -> maintenance print symbols
3837 The following commands are new:
3839 maintenance demangle Call internal GDB demangler routine to
3840 demangle a C++ link name and prints the result.
3841 maintenance print type Print a type chain for a given symbol
3843 * Change to .gdbinit file processing
3845 We now read the $HOME/.gdbinit file before processing the argv arguments
3846 (e.g. reading symbol files or core files). This allows global parameters to
3847 be set, which will apply during the symbol reading. The ./.gdbinit is still
3848 read after argv processing.
3850 * New hosts supported
3852 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3854 GNU/Linux support i386-unknown-linux or linux
3856 We are also including code to support the HP/PA running BSD and HPUX. This
3857 is almost guaranteed not to work, as we didn't have time to test or build it
3858 for this release. We are including it so that the more adventurous (or
3859 masochistic) of you can play with it. We also had major problems with the
3860 fact that the compiler that we got from HP doesn't support the -g option.
3863 * New targets supported
3865 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3867 * More smarts about finding #include files
3869 GDB now remembers the compilation directory for all include files, and for
3870 all files from which C is generated (like yacc and lex sources). This
3871 greatly improves GDB's ability to find yacc/lex sources, and include files,
3872 especially if you are debugging your program from a directory different from
3873 the one that contains your sources.
3875 We also fixed a bug which caused difficulty with listing and setting
3876 breakpoints in include files which contain C code. (In the past, you had to
3877 try twice in order to list an include file that you hadn't looked at before.)
3879 * Interesting infernals change
3881 GDB now deals with arbitrary numbers of sections, where the symbols for each
3882 section must be relocated relative to that section's landing place in the
3883 target's address space. This work was needed to support ELF with embedded
3884 stabs used by Solaris-2.0.
3886 * Bug fixes (of course!)
3888 There have been loads of fixes for the following things:
3889 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3890 i960, stabs, DOS(GO32), procfs, etc...
3892 See the ChangeLog for details.
3894 *** Changes in GDB-4.5:
3896 * New machines supported (host and target)
3898 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3900 SGI Irix-4.x mips-sgi-irix4 or iris4
3902 * New malloc package
3904 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3905 Mmalloc is capable of handling mutiple heaps of memory. It is also
3906 capable of saving a heap to a file, and then mapping it back in later.
3907 This can be used to greatly speedup the startup of GDB by using a
3908 pre-parsed symbol table which lives in a mmalloc managed heap. For
3909 more details, please read mmalloc/mmalloc.texi.
3913 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3914 'help info proc' for details.
3916 * MIPS ecoff symbol table format
3918 The code that reads MIPS symbol table format is now supported on all hosts.
3919 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3922 * File name changes for MS-DOS
3924 Many files in the config directories have been renamed to make it easier to
3925 support GDB on MS-DOSe systems (which have very restrictive file name
3926 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3927 environment) is close to working but has some remaining problems. Note
3928 that debugging of DOS programs is not supported, due to limitations
3929 in the ``operating system'', but it can be used to host cross-debugging.
3931 * Cross byte order fixes
3933 Many fixes have been made to support cross debugging of Sparc and MIPS
3934 targets from hosts whose byte order differs.
3936 * New -mapped and -readnow options
3938 If memory-mapped files are available on your system through the 'mmap'
3939 system call, you can use the -mapped option on the `file' or
3940 `symbol-file' commands to cause GDB to write the symbols from your
3941 program into a reusable file. If the program you are debugging is
3942 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3943 Future GDB debugging sessions will notice the presence of this file,
3944 and will quickly map in symbol information from it, rather than reading
3945 the symbol table from the executable program. Using the '-mapped'
3946 option in a GDB `file' or `symbol-file' command has the same effect as
3947 starting GDB with the '-mapped' command-line option.
3949 You can cause GDB to read the entire symbol table immediately by using
3950 the '-readnow' option with any of the commands that load symbol table
3951 information (or on the GDB command line). This makes the command
3952 slower, but makes future operations faster.
3954 The -mapped and -readnow options are typically combined in order to
3955 build a `fred.syms' file that contains complete symbol information.
3956 A simple GDB invocation to do nothing but build a `.syms' file for future
3959 gdb -batch -nx -mapped -readnow programname
3961 The `.syms' file is specific to the host machine on which GDB is run.
3962 It holds an exact image of GDB's internal symbol table. It cannot be
3963 shared across multiple host platforms.
3965 * longjmp() handling
3967 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3968 siglongjmp() without losing control. This feature has not yet been ported to
3969 all systems. It currently works on many 386 platforms, all MIPS-based
3970 platforms (SGI, DECstation, etc), and Sun3/4.
3974 Preliminary work has been put in to support the new Solaris OS from Sun. At
3975 this time, it can control and debug processes, but it is not capable of
3980 As always, many many bug fixes. The major areas were with g++, and mipsread.
3981 People using the MIPS-based platforms should experience fewer mysterious
3982 crashes and trashed symbol tables.
3984 *** Changes in GDB-4.4:
3986 * New machines supported (host and target)
3988 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3990 BSD Reno on Vax vax-dec-bsd
3991 Ultrix on Vax vax-dec-ultrix
3993 * New machines supported (target)
3995 AMD 29000 embedded, using EBMON a29k-none-none
3999 GDB continues to improve its handling of C++. `References' work better.
4000 The demangler has also been improved, and now deals with symbols mangled as
4001 per the Annotated C++ Reference Guide.
4003 GDB also now handles `stabs' symbol information embedded in MIPS
4004 `ecoff' symbol tables. Since the ecoff format was not easily
4005 extensible to handle new languages such as C++, this appeared to be a
4006 good way to put C++ debugging info into MIPS binaries. This option
4007 will be supported in the GNU C compiler, version 2, when it is
4010 * New features for SVR4
4012 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4013 shared libraries. Debugging dynamically linked programs should present
4014 only minor differences from debugging statically linked programs.
4016 The `info proc' command will print out information about any process
4017 on an SVR4 system (including the one you are debugging). At the moment,
4018 it prints the address mappings of the process.
4020 If you bring up GDB on another SVR4 system, please send mail to
4021 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4023 * Better dynamic linking support in SunOS
4025 Reading symbols from shared libraries which contain debugging symbols
4026 now works properly. However, there remain issues such as automatic
4027 skipping of `transfer vector' code during function calls, which
4028 make it harder to debug code in a shared library, than to debug the
4029 same code linked statically.
4033 GDB is now using the latest `getopt' routines from the FSF. This
4034 version accepts the -- prefix for options with long names. GDB will
4035 continue to accept the old forms (-option and +option) as well.
4036 Various single letter abbreviations for options have been explicity
4037 added to the option table so that they won't get overshadowed in the
4038 future by other options that begin with the same letter.
4042 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4043 Many assorted bugs have been handled. Many more remain to be handled.
4044 See the various ChangeLog files (primarily in gdb and bfd) for details.
4047 *** Changes in GDB-4.3:
4049 * New machines supported (host and target)
4051 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4052 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4053 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4055 * Almost SCO Unix support
4057 We had hoped to support:
4058 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4059 (except for core file support), but we discovered very late in the release
4060 that it has problems with process groups that render gdb unusable. Sorry
4061 about that. I encourage people to fix it and post the fixes.
4063 * Preliminary ELF and DWARF support
4065 GDB can read ELF object files on System V Release 4, and can handle
4066 debugging records for C, in DWARF format, in ELF files. This support
4067 is preliminary. If you bring up GDB on another SVR4 system, please
4068 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4073 GDB now uses the latest `readline' library. One user-visible change
4074 is that two tabs will list possible command completions, which previously
4075 required typing M-? (meta-question mark, or ESC ?).
4079 The `stepi' bug that many of you noticed has been squashed.
4080 Many bugs in C++ have been handled. Many more remain to be handled.
4081 See the various ChangeLog files (primarily in gdb and bfd) for details.
4083 * State of the MIPS world (in case you wondered):
4085 GDB can understand the symbol tables emitted by the compilers
4086 supplied by most vendors of MIPS-based machines, including DEC. These
4087 symbol tables are in a format that essentially nobody else uses.
4089 Some versions of gcc come with an assembler post-processor called
4090 mips-tfile. This program is required if you want to do source-level
4091 debugging of gcc-compiled programs. I believe FSF does not ship
4092 mips-tfile with gcc version 1, but it will eventually come with gcc
4095 Debugging of g++ output remains a problem. g++ version 1.xx does not
4096 really support it at all. (If you're lucky, you should be able to get
4097 line numbers and stack traces to work, but no parameters or local
4098 variables.) With some work it should be possible to improve the
4101 When gcc version 2 is released, you will have somewhat better luck.
4102 However, even then you will get confusing results for inheritance and
4105 We will eventually provide full debugging of g++ output on
4106 DECstations. This will probably involve some kind of stabs-in-ecoff
4107 encapulation, but the details have not been worked out yet.
4110 *** Changes in GDB-4.2:
4112 * Improved configuration
4114 Only one copy of `configure' exists now, and it is not self-modifying.
4115 Porting BFD is simpler.
4119 The `step' and `next' commands now only stop at the first instruction
4120 of a source line. This prevents the multiple stops that used to occur
4121 in switch statements, for-loops, etc. `Step' continues to stop if a
4122 function that has debugging information is called within the line.
4126 Lots of small bugs fixed. More remain.
4128 * New host supported (not target)
4130 Intel 386 PC clone running Mach i386-none-mach
4133 *** Changes in GDB-4.1:
4135 * Multiple source language support
4137 GDB now has internal scaffolding to handle several source languages.
4138 It determines the type of each source file from its filename extension,
4139 and will switch expression parsing and number formatting to match the
4140 language of the function in the currently selected stack frame.
4141 You can also specifically set the language to be used, with
4142 `set language c' or `set language modula-2'.
4146 GDB now has preliminary support for the GNU Modula-2 compiler,
4147 currently under development at the State University of New York at
4148 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4149 continue through the fall of 1991 and into 1992.
4151 Other Modula-2 compilers are currently not supported, and attempting to
4152 debug programs compiled with them will likely result in an error as the
4153 symbol table is read. Feel free to work on it, though!
4155 There are hooks in GDB for strict type checking and range checking,
4156 in the `Modula-2 philosophy', but they do not currently work.
4160 GDB can now write to executable and core files (e.g. patch
4161 a variable's value). You must turn this switch on, specify
4162 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4163 by assigning a new value to a variable. Modifications take
4166 * Automatic SunOS shared library reading
4168 When you run your program, GDB automatically determines where its
4169 shared libraries (if any) have been loaded, and reads their symbols.
4170 The `share' command is no longer needed. This also works when
4171 examining core files.
4175 You can specify the number of lines that the `list' command shows.
4178 * New machines supported (host and target)
4180 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4181 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4182 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4184 * New hosts supported (not targets)
4186 IBM RT/PC: romp-ibm-aix or rtpc
4188 * New targets supported (not hosts)
4190 AMD 29000 embedded with COFF a29k-none-coff
4191 AMD 29000 embedded with a.out a29k-none-aout
4192 Ultracomputer remote kernel debug a29k-nyu-kern
4194 * New remote interfaces
4200 *** Changes in GDB-4.0:
4204 Wide output is wrapped at good places to make the output more readable.
4206 Gdb now supports cross-debugging from a host machine of one type to a
4207 target machine of another type. Communication with the target system
4208 is over serial lines. The ``target'' command handles connecting to the
4209 remote system; the ``load'' command will download a program into the
4210 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4211 also supports debugging of realtime processes running under VxWorks,
4212 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4213 stub on the target system.
4215 New CPUs supported include the AMD 29000 and Intel 960.
4217 GDB now reads object files and symbol tables via a ``binary file''
4218 library, which allows a single copy of GDB to debug programs of multiple
4219 object file types such as a.out and coff.
4221 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4222 refcard.dvi and refcard.ps are available to format it).
4225 * Control-Variable user interface simplified
4227 All variables that control the operation of the debugger can be set
4228 by the ``set'' command, and displayed by the ``show'' command.
4230 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4231 ``Show prompt'' produces the response:
4232 Gdb's prompt is new-gdb=>.
4234 What follows are the NEW set commands. The command ``help set'' will
4235 print a complete list of old and new set commands. ``help set FOO''
4236 will give a longer description of the variable FOO. ``show'' will show
4237 all of the variable descriptions and their current settings.
4239 confirm on/off: Enables warning questions for operations that are
4240 hard to recover from, e.g. rerunning the program while
4241 it is already running. Default is ON.
4243 editing on/off: Enables EMACS style command line editing
4244 of input. Previous lines can be recalled with
4245 control-P, the current line can be edited with control-B,
4246 you can search for commands with control-R, etc.
4249 history filename NAME: NAME is where the gdb command history
4250 will be stored. The default is .gdb_history,
4251 or the value of the environment variable
4254 history size N: The size, in commands, of the command history. The
4255 default is 256, or the value of the environment variable
4258 history save on/off: If this value is set to ON, the history file will
4259 be saved after exiting gdb. If set to OFF, the
4260 file will not be saved. The default is OFF.
4262 history expansion on/off: If this value is set to ON, then csh-like
4263 history expansion will be performed on
4264 command line input. The default is OFF.
4266 radix N: Sets the default radix for input and output. It can be set
4267 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4268 in the current radix, so "set radix 10" is always a no-op.
4270 height N: This integer value is the number of lines on a page. Default
4271 is 24, the current `stty rows'' setting, or the ``li#''
4272 setting from the termcap entry matching the environment
4275 width N: This integer value is the number of characters on a line.
4276 Default is 80, the current `stty cols'' setting, or the ``co#''
4277 setting from the termcap entry matching the environment
4280 Note: ``set screensize'' is obsolete. Use ``set height'' and
4281 ``set width'' instead.
4283 print address on/off: Print memory addresses in various command displays,
4284 such as stack traces and structure values. Gdb looks
4285 more ``symbolic'' if you turn this off; it looks more
4286 ``machine level'' with it on. Default is ON.
4288 print array on/off: Prettyprint arrays. New convenient format! Default
4291 print demangle on/off: Print C++ symbols in "source" form if on,
4294 print asm-demangle on/off: Same, for assembler level printouts
4297 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4300 * Support for Epoch Environment.
4302 The epoch environment is a version of Emacs v18 with windowing. One
4303 new command, ``inspect'', is identical to ``print'', except that if you
4304 are running in the epoch environment, the value is printed in its own
4308 * Support for Shared Libraries
4310 GDB can now debug programs and core files that use SunOS shared libraries.
4311 Symbols from a shared library cannot be referenced
4312 before the shared library has been linked with the program (this
4313 happens after you type ``run'' and before the function main() is entered).
4314 At any time after this linking (including when examining core files
4315 from dynamically linked programs), gdb reads the symbols from each
4316 shared library when you type the ``sharedlibrary'' command.
4317 It can be abbreviated ``share''.
4319 sharedlibrary REGEXP: Load shared object library symbols for files
4320 matching a unix regular expression. No argument
4321 indicates to load symbols for all shared libraries.
4323 info sharedlibrary: Status of loaded shared libraries.
4328 A watchpoint stops execution of a program whenever the value of an
4329 expression changes. Checking for this slows down execution
4330 tremendously whenever you are in the scope of the expression, but is
4331 quite useful for catching tough ``bit-spreader'' or pointer misuse
4332 problems. Some machines such as the 386 have hardware for doing this
4333 more quickly, and future versions of gdb will use this hardware.
4335 watch EXP: Set a watchpoint (breakpoint) for an expression.
4337 info watchpoints: Information about your watchpoints.
4339 delete N: Deletes watchpoint number N (same as breakpoints).
4340 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4341 enable N: Re-enables watchpoint number N (same as breakpoints).
4344 * C++ multiple inheritance
4346 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4349 * C++ exception handling
4351 Gdb now supports limited C++ exception handling. Besides the existing
4352 ability to breakpoint on an exception handler, gdb can breakpoint on
4353 the raising of an exception (before the stack is peeled back to the
4356 catch FOO: If there is a FOO exception handler in the dynamic scope,
4357 set a breakpoint to catch exceptions which may be raised there.
4358 Multiple exceptions (``catch foo bar baz'') may be caught.
4360 info catch: Lists all exceptions which may be caught in the
4361 current stack frame.
4364 * Minor command changes
4366 The command ``call func (arg, arg, ...)'' now acts like the print
4367 command, except it does not print or save a value if the function's result
4368 is void. This is similar to dbx usage.
4370 The ``up'' and ``down'' commands now always print the frame they end up
4371 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4372 frames without printing.
4374 * New directory command
4376 'dir' now adds directories to the FRONT of the source search path.
4377 The path starts off empty. Source files that contain debug information
4378 about the directory in which they were compiled can be found even
4379 with an empty path; Sun CC and GCC include this information. If GDB can't
4380 find your source file in the current directory, type "dir .".
4382 * Configuring GDB for compilation
4384 For normal use, type ``./configure host''. See README or gdb.texinfo
4387 GDB now handles cross debugging. If you are remotely debugging between
4388 two different machines, type ``./configure host -target=targ''.
4389 Host is the machine where GDB will run; targ is the machine
4390 where the program that you are debugging will run.