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 *** Changes in GDB 7.2
72 * Shared library support for remote targets by default
74 When GDB is configured for a generic, non-OS specific target, like
75 for example, --target=arm-eabi or one of the many *-*-elf targets,
76 GDB now queries remote stubs for loaded shared libraries using the
77 `qXfer:libraries:read' packet. Previously, shared library support
78 was always disabled for such configurations.
82 ** Argument Dependent Lookup (ADL)
84 In C++ ADL lookup directs function search to the namespaces of its
85 arguments even if the namespace has not been imported.
95 Here the compiler will search for `foo' in the namespace of 'b'
96 and find A::foo. GDB now supports this. This construct is commonly
97 used in the Standard Template Library for operators.
99 ** Improved User Defined Operator Support
101 In addition to member operators, GDB now supports lookup of operators
102 defined in a namespace and imported with a `using' directive, operators
103 defined in the global scope, operators imported implicitly from an
104 anonymous namespace, and the ADL operators mentioned in the previous
106 GDB now also supports proper overload resolution for all the previously
107 mentioned flavors of operators.
109 ** static const class members
111 Printing of static const class members that are initialized in the
112 class definition has been fixed.
114 * Windows Thread Information Block access.
116 On Windows targets, GDB now supports displaying the Windows Thread
117 Information Block (TIB) structure. This structure is visible either
118 by using the new command `info w32 thread-information-block' or, by
119 dereferencing the new convenience variable named `$_tlb', a
120 thread-specific pointer to the TIB. This feature is also supported
121 when remote debugging using GDBserver.
125 Static tracepoints are calls in the user program into a tracing
126 library. One such library is a port of the LTTng kernel tracer to
127 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
128 When debugging with GDBserver, GDB now supports combining the GDB
129 tracepoint machinery with such libraries. For example: the user can
130 use GDB to probe a static tracepoint marker (a call from the user
131 program into the tracing library) with the new "strace" command (see
132 "New commands" below). This creates a "static tracepoint" in the
133 breakpoint list, that can be manipulated with the same feature set
134 as fast and regular tracepoints. E.g., collect registers, local and
135 global variables, collect trace state variables, and define
136 tracepoint conditions. In addition, the user can collect extra
137 static tracepoint marker specific data, by collecting the new
138 $_sdata internal variable. When analyzing the trace buffer, you can
139 inspect $_sdata like any other variable available to GDB. For more
140 information, see the "Tracepoints" chapter in GDB user manual. New
141 remote packets have been defined to support static tracepoints, see
142 the "New remote packets" section below.
144 * Better reconstruction of tracepoints after disconnected tracing
146 GDB will attempt to download the original source form of tracepoint
147 definitions when starting a trace run, and then will upload these
148 upon reconnection to the target, resulting in a more accurate
149 reconstruction of the tracepoints that are in use on the target.
153 You can now exercise direct control over the ways that GDB can
154 affect your program. For instance, you can disallow the setting of
155 breakpoints, so that the program can run continuously (assuming
156 non-stop mode). In addition, the "observer" variable is available
157 to switch all of the different controls; in observer mode, GDB
158 cannot affect the target's behavior at all, which is useful for
159 tasks like diagnosing live systems in the field.
161 * The new convenience variable $_thread holds the number of the
168 Return the address of the Windows Thread Information Block of a given thread.
172 In response to several of the tracepoint packets, the target may now
173 also respond with a number of intermediate `qRelocInsn' request
174 packets before the final result packet, to have GDB handle
175 relocating an instruction to execute at a different address. This
176 is particularly useful for stubs that support fast tracepoints. GDB
177 reports support for this feature in the qSupported packet.
181 List static tracepoint markers in the target program.
185 List static tracepoint markers at a given address in the target
188 qXfer:statictrace:read
190 Read the static trace data collected (by a `collect $_sdata'
191 tracepoint action). The remote stub reports support for this packet
192 to gdb's qSupported query.
196 Send the current settings of GDB's permission flags.
200 Send part of the source (textual) form of a tracepoint definition,
201 which includes location, conditional, and action list.
203 * The source command now accepts a -s option to force searching for the
204 script in the source search path even if the script name specifies
207 * New features in the GDB remote stub, GDBserver
209 - GDBserver now support tracepoints (including fast tracepoints, and
210 static tracepoints). The feature is currently supported by the
211 i386-linux and amd64-linux builds. See the "Tracepoints support
212 in gdbserver" section in the manual for more information.
214 GDBserver JIT compiles the tracepoint's conditional agent
215 expression bytecode into native code whenever possible for low
216 overhead dynamic tracepoints conditionals. For such tracepoints,
217 an expression that examines program state is evaluated when the
218 tracepoint is reached, in order to determine whether to capture
219 trace data. If the condition is simple and false, processing the
220 tracepoint finishes very quickly and no data is gathered.
222 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
223 for static tracepoints support.
225 - GDBserver now supports x86_64 Windows 64-bit debugging.
227 * GDB now sends xmlRegisters= in qSupported packet to indicate that
228 it understands register description.
230 * The --batch flag now disables pagination and queries.
232 * X86 general purpose registers
234 GDB now supports reading/writing byte, word and double-word x86
235 general purpose registers directly. This means you can use, say,
236 $ah or $ax to refer, respectively, to the byte register AH and
237 16-bit word register AX that are actually portions of the 32-bit
238 register EAX or 64-bit register RAX.
240 * The `commands' command now accepts a range of breakpoints to modify.
241 A plain `commands' following a command that creates multiple
242 breakpoints affects all the breakpoints set by that command. This
243 applies to breakpoints set by `rbreak', and also applies when a
244 single `break' command creates multiple breakpoints (e.g.,
245 breakpoints on overloaded c++ functions).
247 * The `rbreak' command now accepts a filename specification as part of
248 its argument, limiting the functions selected by the regex to those
249 in the specified file.
251 * Support for remote debugging Windows and SymbianOS shared libraries
252 from Unix hosts has been improved. Non Windows GDB builds now can
253 understand target reported file names that follow MS-DOS based file
254 system semantics, such as file names that include drive letters and
255 use the backslash character as directory separator. This makes it
256 possible to transparently use the "set sysroot" and "set
257 solib-search-path" on Unix hosts to point as host copies of the
258 target's shared libraries. See the new command "set
259 target-file-system-kind" described below, and the "Commands to
260 specify files" section in the user manual for more information.
264 eval template, expressions...
265 Convert the values of one or more expressions under the control
266 of the string template to a command line, and call it.
268 set target-file-system-kind unix|dos-based|auto
269 show target-file-system-kind
270 Set or show the assumed file system kind for target reported file
273 save breakpoints <filename>
274 Save all current breakpoint definitions to a file suitable for use
275 in a later debugging session. To read the saved breakpoint
276 definitions, use the `source' command.
278 `save tracepoints' is a new alias for `save-tracepoints'. The latter
281 info static-tracepoint-markers
282 Display information about static tracepoint markers in the target.
284 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
285 Define a static tracepoint by probing a marker at the given
286 function, line, address, or marker ID.
290 Enable and disable observer mode.
292 set may-write-registers on|off
293 set may-write-memory on|off
294 set may-insert-breakpoints on|off
295 set may-insert-tracepoints on|off
296 set may-insert-fast-tracepoints on|off
297 set may-interrupt on|off
298 Set individual permissions for GDB effects on the target. Note that
299 some of these settings can have undesirable or surprising
300 consequences, particularly when changed in the middle of a session.
301 For instance, disabling the writing of memory can prevent
302 breakpoints from being inserted, cause single-stepping to fail, or
303 even crash your program, if you disable after breakpoints have been
304 inserted. However, GDB should not crash.
306 set record memory-query on|off
307 show record memory-query
308 Control whether to stop the inferior if memory changes caused
309 by an instruction cannot be recorded.
314 The disassemble command now supports "start,+length" form of two arguments.
318 ** GDB now provides a new directory location, called the python directory,
319 where Python scripts written for GDB can be installed. The location
320 of that directory is <data-directory>/python, where <data-directory>
321 is the GDB data directory. For more details, see section `Scripting
322 GDB using Python' in the manual.
324 ** The GDB Python API now has access to breakpoints, symbols, symbol
325 tables, program spaces, inferiors, threads and frame's code blocks.
326 Additionally, GDB Parameters can now be created from the API, and
327 manipulated via set/show in the CLI.
329 ** New functions gdb.target_charset, gdb.target_wide_charset,
330 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
332 ** New exception gdb.GdbError.
334 ** Pretty-printers are now also looked up in the current program space.
336 ** Pretty-printers can now be individually enabled and disabled.
338 ** GDB now looks for names of Python scripts to auto-load in a
339 special section named `.debug_gdb_scripts', in addition to looking
340 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
342 * Tracepoint actions were unified with breakpoint commands. In particular,
343 there are no longer differences in "info break" output for breakpoints and
344 tracepoints and the "commands" command can be used for both tracepoints and
349 ARM Symbian arm*-*-symbianelf*
351 * D language support.
352 GDB now supports debugging programs written in the D programming
355 * GDB now supports the extended ptrace interface for PowerPC which is
356 available since Linux kernel version 2.6.34. This automatically enables
357 any hardware breakpoints and additional hardware watchpoints available in
358 the processor. The old ptrace interface exposes just one hardware
359 watchpoint and no hardware breakpoints.
361 * GDB is now able to use the Data Value Compare (DVC) register available on
362 embedded PowerPC processors to implement in hardware simple watchpoint
363 conditions of the form:
365 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
367 This works in native GDB running on Linux kernels with the extended ptrace
368 interface mentioned above.
370 *** Changes in GDB 7.1
376 GDB now supports importing of namespaces in C++. This enables the
377 user to inspect variables from imported namespaces. Support for
378 namepace aliasing has also been added. So, if a namespace is
379 aliased in the current scope (e.g. namepace C=A; ) the user can
380 print variables using the alias (e.g. (gdb) print C::x).
384 All known bugs relating to the printing of virtual base class were
385 fixed. It is now possible to call overloaded static methods using a
390 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
391 and reinterpret_cast<> are now handled by the C++ expression parser.
395 Xilinx MicroBlaze microblaze-*-*
400 Xilinx MicroBlaze microblaze
403 * Multi-program debugging.
405 GDB now has support for multi-program (a.k.a. multi-executable or
406 multi-exec) debugging. This allows for debugging multiple inferiors
407 simultaneously each running a different program under the same GDB
408 session. See "Debugging Multiple Inferiors and Programs" in the
409 manual for more information. This implied some user visible changes
410 in the multi-inferior support. For example, "info inferiors" now
411 lists inferiors that are not running yet or that have exited
412 already. See also "New commands" and "New options" below.
414 * New tracing features
416 GDB's tracepoint facility now includes several new features:
418 ** Trace state variables
420 GDB tracepoints now include support for trace state variables, which
421 are variables managed by the target agent during a tracing
422 experiment. They are useful for tracepoints that trigger each
423 other, so for instance one tracepoint can count hits in a variable,
424 and then a second tracepoint has a condition that is true when the
425 count reaches a particular value. Trace state variables share the
426 $-syntax of GDB convenience variables, and can appear in both
427 tracepoint actions and condition expressions. Use the "tvariable"
428 command to create, and "info tvariables" to view; see "Trace State
429 Variables" in the manual for more detail.
433 GDB now includes an option for defining fast tracepoints, which
434 targets may implement more efficiently, such as by installing a jump
435 into the target agent rather than a trap instruction. The resulting
436 speedup can be by two orders of magnitude or more, although the
437 tradeoff is that some program locations on some target architectures
438 might not allow fast tracepoint installation, for instance if the
439 instruction to be replaced is shorter than the jump. To request a
440 fast tracepoint, use the "ftrace" command, with syntax identical to
441 the regular trace command.
443 ** Disconnected tracing
445 It is now possible to detach GDB from the target while it is running
446 a trace experiment, then reconnect later to see how the experiment
447 is going. In addition, a new variable disconnected-tracing lets you
448 tell the target agent whether to continue running a trace if the
449 connection is lost unexpectedly.
453 GDB now has the ability to save the trace buffer into a file, and
454 then use that file as a target, similarly to you can do with
455 corefiles. You can select trace frames, print data that was
456 collected in them, and use tstatus to display the state of the
457 tracing run at the moment that it was saved. To create a trace
458 file, use "tsave <filename>", and to use it, do "target tfile
461 ** Circular trace buffer
463 You can ask the target agent to handle the trace buffer as a
464 circular buffer, discarding the oldest trace frames to make room for
465 newer ones, by setting circular-trace-buffer to on. This feature may
466 not be available for all target agents.
471 The disassemble command, when invoked with two arguments, now requires
472 the arguments to be comma-separated.
475 The info variables command now displays variable definitions. Files
476 which only declare a variable are not shown.
479 The source command is now capable of sourcing Python scripts.
480 This feature is dependent on the debugger being build with Python
483 Related to this enhancement is also the introduction of a new command
484 "set script-extension" (see below).
486 * New commands (for set/show, see "New options" below)
488 record save [<FILENAME>]
489 Save a file (in core file format) containing the process record
490 execution log for replay debugging at a later time.
492 record restore <FILENAME>
493 Restore the process record execution log that was saved at an
494 earlier time, for replay debugging.
496 add-inferior [-copies <N>] [-exec <FILENAME>]
499 clone-inferior [-copies <N>] [ID]
500 Make a new inferior ready to execute the same program another
506 maint info program-spaces
507 List the program spaces loaded into GDB.
509 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
510 show remote interrupt-sequence
511 Allow the user to select one of ^C, a BREAK signal or BREAK-g
512 as the sequence to the remote target in order to interrupt the execution.
513 Ctrl-C is a default. Some system prefers BREAK which is high level of
514 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
515 Magic SysRq g. It is BREAK signal and character 'g'.
517 set remote interrupt-on-connect [on | off]
518 show remote interrupt-on-connect
519 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
520 remote target when gdb connects to it. This is needed when you debug
523 set remotebreak [on | off]
525 Deprecated. Use "set/show remote interrupt-sequence" instead.
527 tvariable $NAME [ = EXP ]
528 Create or modify a trace state variable.
531 List trace state variables and their values.
533 delete tvariable $NAME ...
534 Delete one or more trace state variables.
537 Evaluate the given expressions without collecting anything into the
538 trace buffer. (Valid in tracepoint actions only.)
540 ftrace FN / FILE:LINE / *ADDR
541 Define a fast tracepoint at the given function, line, or address.
543 * New expression syntax
545 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
546 GDB now parses 0b101010 identically with 42.
550 set follow-exec-mode new|same
551 show follow-exec-mode
552 Control whether GDB reuses the same inferior across an exec call or
553 creates a new one. This is useful to be able to restart the old
554 executable after the inferior having done an exec call.
556 set default-collect EXPR, ...
558 Define a list of expressions to be collected at each tracepoint.
559 This is a useful way to ensure essential items are not overlooked,
560 such as registers or a critical global variable.
562 set disconnected-tracing
563 show disconnected-tracing
564 If set to 1, the target is instructed to continue tracing if it
565 loses its connection to GDB. If 0, the target is to stop tracing
568 set circular-trace-buffer
569 show circular-trace-buffer
570 If set to on, the target is instructed to use a circular trace buffer
571 and discard the oldest trace frames instead of stopping the trace due
572 to a full trace buffer. If set to off, the trace stops when the buffer
573 fills up. Some targets may not support this.
575 set script-extension off|soft|strict
576 show script-extension
577 If set to "off", the debugger does not perform any script language
578 recognition, and all sourced files are assumed to be GDB scripts.
579 If set to "soft" (the default), files are sourced according to
580 filename extension, falling back to GDB scripts if the first
582 If set to "strict", files are sourced according to filename extension.
584 set ada trust-PAD-over-XVS on|off
585 show ada trust-PAD-over-XVS
586 If off, activate a workaround against a bug in the debugging information
587 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
588 the GCC sources for more information about the GNAT encoding and
589 PAD types in particular). It is always safe to set this option to
590 off, but this introduces a slight performance penalty. The default
593 * Python API Improvements
595 ** GDB provides the new class gdb.LazyString. This is useful in
596 some pretty-printing cases. The new method gdb.Value.lazy_string
597 provides a simple way to create objects of this type.
599 ** The fields returned by gdb.Type.fields now have an
600 `is_base_class' attribute.
602 ** The new method gdb.Type.range returns the range of an array type.
604 ** The new method gdb.parse_and_eval can be used to parse and
605 evaluate an expression.
610 Define a trace state variable.
613 Get the current value of a trace state variable.
616 Set desired tracing behavior upon disconnection.
619 Set the trace buffer to be linear or circular.
622 Get data about the tracepoints currently in use.
626 Process record now works correctly with hardware watchpoints.
628 Multiple bug fixes have been made to the mips-irix port, making it
629 much more reliable. In particular:
630 - Debugging threaded applications is now possible again. Previously,
631 GDB would hang while starting the program, or while waiting for
632 the program to stop at a breakpoint.
633 - Attaching to a running process no longer hangs.
634 - An error occurring while loading a core file has been fixed.
635 - Changing the value of the PC register now works again. This fixes
636 problems observed when using the "jump" command, or when calling
637 a function from GDB, or even when assigning a new value to $pc.
638 - With the "finish" and "return" commands, the return value for functions
639 returning a small array is now correctly printed.
640 - It is now possible to break on shared library code which gets executed
641 during a shared library init phase (code executed while executing
642 their .init section). Previously, the breakpoint would have no effect.
643 - GDB is now able to backtrace through the signal handler for
644 non-threaded programs.
646 PIE (Position Independent Executable) programs debugging is now supported.
647 This includes debugging execution of PIC (Position Independent Code) shared
648 libraries although for that, it should be possible to run such libraries as an
651 *** Changes in GDB 7.0
653 * GDB now has an interface for JIT compilation. Applications that
654 dynamically generate code can create symbol files in memory and register
655 them with GDB. For users, the feature should work transparently, and
656 for JIT developers, the interface is documented in the GDB manual in the
657 "JIT Compilation Interface" chapter.
659 * Tracepoints may now be conditional. The syntax is as for
660 breakpoints; either an "if" clause appended to the "trace" command,
661 or the "condition" command is available. GDB sends the condition to
662 the target for evaluation using the same bytecode format as is used
663 for tracepoint actions.
665 * The disassemble command now supports: an optional /r modifier, print the
666 raw instructions in hex as well as in symbolic form, and an optional /m
667 modifier to print mixed source+assembly.
669 * Process record and replay
671 In a architecture environment that supports ``process record and
672 replay'', ``process record and replay'' target can record a log of
673 the process execution, and replay it with both forward and reverse
676 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
677 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
678 set execution-direction {forward|reverse}, for targets that support
681 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
682 feature is available with a native GDB running on kernel version
685 * GDB now has support for multi-byte and wide character sets on the
686 target. Strings whose character type is wchar_t, char16_t, or
687 char32_t are now correctly printed. GDB supports wide- and unicode-
688 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
689 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
690 `printf'. This feature requires iconv to work properly; if your
691 system does not have a working iconv, GDB can use GNU libiconv. See
692 the installation instructions for more information.
694 * GDB now supports automatic retrieval of shared library files from
695 remote targets. To use this feature, specify a system root that begins
696 with the `remote:' prefix, either via the `set sysroot' command or via
697 the `--with-sysroot' configure-time option.
699 * "info sharedlibrary" now takes an optional regex of libraries to show,
700 and it now reports if a shared library has no debugging information.
702 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
703 now complete on file names.
705 * When completing in expressions, gdb will attempt to limit
706 completions to allowable structure or union fields, where appropriate.
707 For instance, consider:
709 # struct example { int f1; double f2; };
710 # struct example variable;
713 If the user types TAB at the end of this command line, the available
714 completions will be "f1" and "f2".
716 * Inlined functions are now supported. They show up in backtraces, and
717 the "step", "next", and "finish" commands handle them automatically.
719 * GDB now supports the token-splicing (##) and stringification (#)
720 operators when expanding macros. It also supports variable-arity
723 * GDB now supports inspecting extra signal information, exported by
724 the new $_siginfo convenience variable. The feature is currently
725 implemented on linux ARM, i386 and amd64.
727 * GDB can now display the VFP floating point registers and NEON vector
728 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
729 can provide these registers (requires Linux 2.6.30 or later). Remote
730 and simulator targets may also provide them.
735 Search memory for a sequence of bytes.
738 Turn off `+'/`-' protocol acknowledgments to permit more efficient
739 operation over reliable transport links. Use of this packet is
740 controlled by the `set remote noack-packet' command.
743 Kill the process with the specified process ID. Use this in preference
744 to `k' when multiprocess protocol extensions are supported.
747 Obtains additional operating system information
751 Read or write additional signal information.
753 * Removed remote protocol undocumented extension
755 An undocumented extension to the remote protocol's `S' stop reply
756 packet that permited the stub to pass a process id was removed.
757 Remote servers should use the `T' stop reply packet instead.
759 * GDB now supports multiple function calling conventions according to the
760 DWARF-2 DW_AT_calling_convention function attribute.
762 * The SH target utilizes the aforementioned change to distinguish between gcc
763 and Renesas calling convention. It also adds the new CLI commands
764 `set/show sh calling-convention'.
766 * GDB can now read compressed debug sections, as produced by GNU gold
767 with the --compress-debug-sections=zlib flag.
769 * 64-bit core files are now supported on AIX.
771 * Thread switching is now supported on Tru64.
773 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
774 which will be allocated using malloc later in program execution.
776 * The qXfer:libraries:read remote procotol packet now allows passing a
777 list of section offsets.
779 * On GNU/Linux, GDB can now attach to stopped processes. Several race
780 conditions handling signals delivered during attach or thread creation
781 have also been fixed.
783 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
784 From the user's standpoint, all unqualified instances of True and False
785 are treated as the standard definitions, regardless of context.
787 * GDB now parses C++ symbol and type names more flexibly. For
790 template<typename T> class C { };
793 GDB will now correctly handle all of:
795 ptype C<char const *>
797 ptype C<const char *>
800 * New features in the GDB remote stub, gdbserver
802 - The "--wrapper" command-line argument tells gdbserver to use a
803 wrapper program to launch programs for debugging.
805 - On PowerPC and S/390 targets, it is now possible to use a single
806 gdbserver executable to debug both 32-bit and 64-bit programs.
807 (This requires gdbserver itself to be built as a 64-bit executable.)
809 - gdbserver uses the new noack protocol mode for TCP connections to
810 reduce communications latency, if also supported and enabled in GDB.
812 - Support for the sparc64-linux-gnu target is now included in
815 - The amd64-linux build of gdbserver now supports debugging both
816 32-bit and 64-bit programs.
818 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
819 now support hardware watchpoints, and will use them automatically
824 GDB now has support for scripting using Python. Whether this is
825 available is determined at configure time.
827 New GDB commands can now be written in Python.
829 * Ada tasking support
831 Ada tasks can now be inspected in GDB. The following commands have
835 Print the list of Ada tasks.
837 Print detailed information about task number N.
839 Print the task number of the current task.
841 Switch the context of debugging to task number N.
843 * Support for user-defined prefixed commands. The "define" command can
844 add new commands to existing prefixes, e.g. "target".
846 * Multi-inferior, multi-process debugging.
848 GDB now has generalized support for multi-inferior debugging. See
849 "Debugging Multiple Inferiors" in the manual for more information.
850 Although availability still depends on target support, the command
851 set is more uniform now. The GNU/Linux specific multi-forks support
852 has been migrated to this new framework. This implied some user
853 visible changes; see "New commands" and also "Removed commands"
856 * Target descriptions can now describe the target OS ABI. See the
857 "Target Description Format" section in the user manual for more
860 * Target descriptions can now describe "compatible" architectures
861 to indicate that the target can execute applications for a different
862 architecture in addition to those for the main target architecture.
863 See the "Target Description Format" section in the user manual for
866 * Multi-architecture debugging.
868 GDB now includes general supports for debugging applications on
869 hybrid systems that use more than one single processor architecture
870 at the same time. Each such hybrid architecture still requires
871 specific support to be added. The only hybrid architecture supported
872 in this version of GDB is the Cell Broadband Engine.
874 * GDB now supports integrated debugging of Cell/B.E. applications that
875 use both the PPU and SPU architectures. To enable support for hybrid
876 Cell/B.E. debugging, you need to configure GDB to support both the
877 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
878 --enable-targets configure option.
880 * Non-stop mode debugging.
882 For some targets, GDB now supports an optional mode of operation in
883 which you can examine stopped threads while other threads continue
884 to execute freely. This is referred to as non-stop mode, with the
885 old mode referred to as all-stop mode. See the "Non-Stop Mode"
886 section in the user manual for more information.
888 To be able to support remote non-stop debugging, a remote stub needs
889 to implement the non-stop mode remote protocol extensions, as
890 described in the "Remote Non-Stop" section of the user manual. The
891 GDB remote stub, gdbserver, has been adjusted to support these
892 extensions on linux targets.
894 * New commands (for set/show, see "New options" below)
896 catch syscall [NAME(S) | NUMBER(S)]
897 Catch system calls. Arguments, which should be names of system
898 calls or their numbers, mean catch only those syscalls. Without
899 arguments, every syscall will be caught. When the inferior issues
900 any of the specified syscalls, GDB will stop and announce the system
901 call, both when it is called and when its call returns. This
902 feature is currently available with a native GDB running on the
903 Linux Kernel, under the following architectures: x86, x86_64,
904 PowerPC and PowerPC64.
906 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
908 Search memory for a sequence of bytes.
910 maint set python print-stack
911 maint show python print-stack
912 Show a stack trace when an error is encountered in a Python script.
915 Invoke CODE by passing it to the Python interpreter.
920 These allow macros to be defined, undefined, and listed
924 Show operating system information about processes.
927 List the inferiors currently under GDB's control.
930 Switch focus to inferior number NUM.
933 Detach from inferior number NUM.
936 Kill inferior number NUM.
941 show spu stop-on-load
942 Control whether to stop for new SPE threads during Cell/B.E. debugging.
944 set spu auto-flush-cache
945 show spu auto-flush-cache
946 Control whether to automatically flush the software-managed cache
947 during Cell/B.E. debugging.
949 set sh calling-convention
950 show sh calling-convention
951 Control the calling convention used when calling SH target functions.
955 Control display of timestamps with GDB debugging output.
957 set disassemble-next-line
958 show disassemble-next-line
959 Control display of disassembled source lines or instructions when
962 set remote noack-packet
963 show remote noack-packet
964 Set/show the use of remote protocol QStartNoAckMode packet. See above
965 under "New remote packets."
967 set remote query-attached-packet
968 show remote query-attached-packet
969 Control use of remote protocol `qAttached' (query-attached) packet.
971 set remote read-siginfo-object
972 show remote read-siginfo-object
973 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
976 set remote write-siginfo-object
977 show remote write-siginfo-object
978 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
981 set remote reverse-continue
982 show remote reverse-continue
983 Control use of remote protocol 'bc' (reverse-continue) packet.
985 set remote reverse-step
986 show remote reverse-step
987 Control use of remote protocol 'bs' (reverse-step) packet.
989 set displaced-stepping
990 show displaced-stepping
991 Control displaced stepping mode. Displaced stepping is a way to
992 single-step over breakpoints without removing them from the debuggee.
993 Also known as "out-of-line single-stepping".
997 Control display of debugging info for displaced stepping.
999 maint set internal-error
1000 maint show internal-error
1001 Control what GDB does when an internal error is detected.
1003 maint set internal-warning
1004 maint show internal-warning
1005 Control what GDB does when an internal warning is detected.
1010 Use a wrapper program to launch programs for debugging.
1012 set multiple-symbols (all|ask|cancel)
1013 show multiple-symbols
1014 The value of this variable can be changed to adjust the debugger behavior
1015 when an expression or a breakpoint location contains an ambiguous symbol
1016 name (an overloaded function name, for instance).
1018 set breakpoint always-inserted
1019 show breakpoint always-inserted
1020 Keep breakpoints always inserted in the target, as opposed to inserting
1021 them when resuming the target, and removing them when the target stops.
1022 This option can improve debugger performance on slow remote targets.
1024 set arm fallback-mode (arm|thumb|auto)
1025 show arm fallback-mode
1026 set arm force-mode (arm|thumb|auto)
1028 These commands control how ARM GDB determines whether instructions
1029 are ARM or Thumb. The default for both settings is auto, which uses
1030 the current CPSR value for instructions without symbols; previous
1031 versions of GDB behaved as if "set arm fallback-mode arm".
1033 set disable-randomization
1034 show disable-randomization
1035 Standalone programs run with the virtual address space randomization enabled
1036 by default on some platforms. This option keeps the addresses stable across
1037 multiple debugging sessions.
1041 Control whether other threads are stopped or not when some thread hits
1046 Requests that asynchronous execution is enabled in the target, if available.
1047 In this case, it's possible to resume target in the background, and interact
1048 with GDB while the target is running. "show target-async" displays the
1049 current state of asynchronous execution of the target.
1051 set target-wide-charset
1052 show target-wide-charset
1053 The target-wide-charset is the name of the character set that GDB
1054 uses when printing characters whose type is wchar_t.
1056 set tcp auto-retry (on|off)
1058 set tcp connect-timeout
1059 show tcp connect-timeout
1060 These commands allow GDB to retry failed TCP connections to a remote stub
1061 with a specified timeout period; this is useful if the stub is launched
1062 in parallel with GDB but may not be ready to accept connections immediately.
1064 set libthread-db-search-path
1065 show libthread-db-search-path
1066 Control list of directories which GDB will search for appropriate
1069 set schedule-multiple (on|off)
1070 show schedule-multiple
1071 Allow GDB to resume all threads of all processes or only threads of
1072 the current process.
1076 Use more aggressive caching for accesses to the stack. This improves
1077 performance of remote debugging (particularly backtraces) without
1078 affecting correctness.
1080 set interactive-mode (on|off|auto)
1081 show interactive-mode
1082 Control whether GDB runs in interactive mode (on) or not (off).
1083 When in interactive mode, GDB waits for the user to answer all
1084 queries. Otherwise, GDB does not wait and assumes the default
1085 answer. When set to auto (the default), GDB determines which
1086 mode to use based on the stdin settings.
1091 For program forks, this is replaced by the new more generic `info
1092 inferiors' command. To list checkpoints, you can still use the
1093 `info checkpoints' command, which was an alias for the `info forks'
1097 Replaced by the new `inferior' command. To switch between
1098 checkpoints, you can still use the `restart' command, which was an
1099 alias for the `fork' command.
1102 This is removed, since some targets don't have a notion of
1103 processes. To switch between processes, you can still use the
1104 `inferior' command using GDB's own inferior number.
1107 For program forks, this is replaced by the new more generic `kill
1108 inferior' command. To delete a checkpoint, you can still use the
1109 `delete checkpoint' command, which was an alias for the `delete
1113 For program forks, this is replaced by the new more generic `detach
1114 inferior' command. To detach a checkpoint, you can still use the
1115 `detach checkpoint' command, which was an alias for the `detach
1118 * New native configurations
1120 x86/x86_64 Darwin i[34567]86-*-darwin*
1122 x86_64 MinGW x86_64-*-mingw*
1126 Lattice Mico32 lm32-*
1127 x86 DICOS i[34567]86-*-dicos*
1128 x86_64 DICOS x86_64-*-dicos*
1131 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1132 (mingw32ce) debugging.
1138 These commands were actually not implemented on any target.
1140 *** Changes in GDB 6.8
1142 * New native configurations
1144 NetBSD/hppa hppa*-*netbsd*
1145 Xtensa GNU/Linux xtensa*-*-linux*
1149 NetBSD/hppa hppa*-*-netbsd*
1150 Xtensa GNU/Lunux xtensa*-*-linux*
1152 * Change in command line behavior -- corefiles vs. process ids.
1154 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1155 attaching to process NUMBER fails, GDB no longer attempts to open a
1156 core file named NUMBER. Attaching to a program using the -c option
1157 is no longer supported. Instead, use the '-p' or '--pid' options.
1159 * GDB can now be built as a native debugger for debugging Windows x86
1160 (mingw32) Portable Executable (PE) programs.
1162 * Pending breakpoints no longer change their number when their address
1165 * GDB now supports breakpoints with multiple locations,
1166 including breakpoints on C++ constructors, inside C++ templates,
1167 and in inlined functions.
1169 * GDB's ability to debug optimized code has been improved. GDB more
1170 accurately identifies function bodies and lexical blocks that occupy
1171 more than one contiguous range of addresses.
1173 * Target descriptions can now describe registers for PowerPC.
1175 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1176 registers on PowerPC targets.
1178 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1179 targets even when the libthread_db library is not available.
1181 * The GDB remote stub, gdbserver, now supports the new file transfer
1182 commands (remote put, remote get, and remote delete).
1184 * The GDB remote stub, gdbserver, now supports run and attach in
1185 extended-remote mode.
1187 * hppa*64*-*-hpux11* target broken
1188 The debugger is unable to start a program and fails with the following
1189 error: "Error trying to get information about dynamic linker".
1190 The gdb-6.7 release is also affected.
1192 * GDB now supports the --enable-targets= configure option to allow
1193 building a single GDB executable that supports multiple remote
1194 target architectures.
1196 * GDB now supports debugging C and C++ programs which use the
1197 Decimal Floating Point extension. In addition, the PowerPC target
1198 now has a set of pseudo-registers to inspect decimal float values
1199 stored in two consecutive float registers.
1201 * The -break-insert MI command can optionally create pending
1204 * Improved support for debugging Ada
1205 Many improvements to the Ada language support have been made. These
1207 - Better support for Ada2005 interface types
1208 - Improved handling of arrays and slices in general
1209 - Better support for Taft-amendment types
1210 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1212 - Improved command completion in Ada
1215 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1220 set print frame-arguments (all|scalars|none)
1221 show print frame-arguments
1222 The value of this variable can be changed to control which argument
1223 values should be printed by the debugger when displaying a frame.
1228 Transfer files to and from a remote target, and delete remote files.
1235 Transfer files to and from a remote target, and delete remote files.
1237 * New remote packets
1244 Open, close, read, write, and delete files on the remote system.
1247 Attach to an existing process on the remote system, in extended-remote
1251 Run a new process on the remote system, in extended-remote mode.
1253 *** Changes in GDB 6.7
1255 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1256 bfd, libiberty and opcodes, as revealed by static analysis donated by
1257 Coverity, Inc. (http://scan.coverity.com).
1259 * When looking up multiply-defined global symbols, GDB will now prefer the
1260 symbol definition in the current shared library if it was built using the
1261 -Bsymbolic linker option.
1263 * When the Text User Interface (TUI) is not configured, GDB will now
1264 recognize the -tui command-line option and print a message that the TUI
1267 * The GDB remote stub, gdbserver, now has lower overhead for high
1268 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1270 * GDB for MIPS targets now autodetects whether a remote target provides
1271 32-bit or 64-bit register values.
1273 * Support for C++ member pointers has been improved.
1275 * GDB now understands XML target descriptions, which specify the
1276 target's overall architecture. GDB can read a description from
1277 a local file or over the remote serial protocol.
1279 * Vectors of single-byte data use a new integer type which is not
1280 automatically displayed as character or string data.
1282 * The /s format now works with the print command. It displays
1283 arrays of single-byte integers and pointers to single-byte integers
1286 * Target descriptions can now describe target-specific registers,
1287 for architectures which have implemented the support (currently
1288 only ARM, M68K, and MIPS).
1290 * GDB and the GDB remote stub, gdbserver, now support the XScale
1293 * The GDB remote stub, gdbserver, has been updated to support
1294 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1295 has been rewritten to use the standard GDB remote protocol.
1297 * GDB can now step into C++ functions which are called through thunks.
1299 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1301 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1302 layout. It also supports a TextSeg= and DataSeg= response when only
1303 segment base addresses (rather than offsets) are available.
1305 * The /i format now outputs any trailing branch delay slot instructions
1306 immediately following the last instruction within the count specified.
1308 * The GDB remote protocol "T" stop reply packet now supports a
1309 "library" response. Combined with the new "qXfer:libraries:read"
1310 packet, this response allows GDB to debug shared libraries on targets
1311 where the operating system manages the list of loaded libraries (e.g.
1312 Windows and SymbianOS).
1314 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1315 (DLLs) on Windows and Windows CE targets.
1317 * GDB now supports a faster verification that a .debug file matches its binary
1318 according to its build-id signature, if the signature is present.
1324 Enable or disable hardware flow control (RTS/CTS) on the serial port
1325 when debugging using remote targets.
1327 set mem inaccessible-by-default
1328 show mem inaccessible-by-default
1329 If the target supplies a memory map, for instance via the remote
1330 protocol's "qXfer:memory-map:read" packet, setting this variable
1331 prevents GDB from accessing memory outside the memory map. This
1332 is useful for targets with memory mapped registers or which react
1333 badly to accesses of unmapped address space.
1335 set breakpoint auto-hw
1336 show breakpoint auto-hw
1337 If the target supplies a memory map, for instance via the remote
1338 protocol's "qXfer:memory-map:read" packet, setting this variable
1339 lets GDB use hardware breakpoints automatically for memory regions
1340 where it can not use software breakpoints. This covers both the
1341 "break" command and internal breakpoints used for other commands
1342 including "next" and "finish".
1345 catch exception unhandled
1346 Stop the program execution when Ada exceptions are raised.
1349 Stop the program execution when an Ada assertion failed.
1353 Set an alternate system root for target files. This is a more
1354 general version of "set solib-absolute-prefix", which is now
1355 an alias to "set sysroot".
1358 Provide extended SPU facility status information. This set of
1359 commands is available only when debugging the Cell/B.E. SPU
1362 * New native configurations
1364 OpenBSD/sh sh*-*openbsd*
1367 unset tdesc filename
1369 Use the specified local file as an XML target description, and do
1370 not query the target for its built-in description.
1374 OpenBSD/sh sh*-*-openbsd*
1375 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1376 Toshiba Media Processor mep-elf
1378 * New remote packets
1381 Ignore the specified signals; pass them directly to the debugged program
1382 without stopping other threads or reporting them to GDB.
1384 qXfer:features:read:
1385 Read an XML target description from the target, which describes its
1390 Read or write contents of an spufs file on the target system. These
1391 packets are available only on the Cell/B.E. SPU architecture.
1393 qXfer:libraries:read:
1394 Report the loaded shared libraries. Combined with new "T" packet
1395 response, this packet allows GDB to debug shared libraries on
1396 targets where the operating system manages the list of loaded
1397 libraries (e.g. Windows and SymbianOS).
1401 Support for these obsolete configurations has been removed.
1409 i[34567]86-*-lynxos*
1410 i[34567]86-*-netware*
1411 i[34567]86-*-sco3.2v5*
1412 i[34567]86-*-sco3.2v4*
1414 i[34567]86-*-sysv4.2*
1417 i[34567]86-*-unixware2*
1418 i[34567]86-*-unixware*
1427 * Other removed features
1434 Various m68k-only ROM monitors.
1441 Various Renesas ROM monitors and debugging interfaces for SH and
1446 Support for a Macraigor serial interface to on-chip debugging.
1447 GDB does not directly support the newer parallel or USB
1452 A debug information format. The predecessor to DWARF 2 and
1453 DWARF 3, which are still supported.
1455 Support for the HP aCC compiler on HP-UX/PA-RISC
1457 SOM-encapsulated symbolic debugging information, automatic
1458 invocation of pxdb, and the aCC custom C++ ABI. This does not
1459 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1460 with aCC can still be debugged on an assembly level.
1462 MIPS ".pdr" sections
1464 A MIPS-specific format used to describe stack frame layout
1465 in debugging information.
1469 GDB could work with an older version of Guile to debug
1470 the interpreter and Scheme programs running in it.
1472 set mips stack-arg-size
1473 set mips saved-gpreg-size
1475 Use "set mips abi" to control parameter passing for MIPS.
1477 *** Changes in GDB 6.6
1482 Cell Broadband Engine SPU spu-elf
1484 * GDB can now be configured as a cross-debugger targeting native Windows
1485 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1486 running on a Windows system over TCP/IP to debug Windows programs.
1488 * The GDB remote stub, gdbserver, has been updated to support Windows and
1489 Cygwin debugging. Both single-threaded and multi-threaded programs are
1492 * The "set trust-readonly-sections" command works again. This command was
1493 broken in GDB 6.3, 6.4, and 6.5.
1495 * The "load" command now supports writing to flash memory, if the remote
1496 stub provides the required support.
1498 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1499 longer requires symbolic debug information (e.g. DWARF-2).
1504 unset substitute-path
1505 show substitute-path
1506 Manage a list of substitution rules that GDB uses to rewrite the name
1507 of the directories where the sources are located. This can be useful
1508 for instance when the sources were moved to a different location
1509 between compilation and debugging.
1513 Print each CLI command as it is executed. Each command is prefixed with
1514 a number of `+' symbols representing the nesting depth.
1515 The source command now has a `-v' option to enable the same feature.
1519 The ARM Demon monitor support (RDP protocol, "target rdp").
1521 Kernel Object Display, an embedded debugging feature which only worked with
1522 an obsolete version of Cisco IOS.
1524 The 'set download-write-size' and 'show download-write-size' commands.
1526 * New remote packets
1529 Tell a stub about GDB client features, and request remote target features.
1530 The first feature implemented is PacketSize, which allows the target to
1531 specify the size of packets it can handle - to minimize the number of
1532 packets required and improve performance when connected to a remote
1536 Fetch an OS auxilliary vector from the remote stub. This packet is a
1537 more efficient replacement for qPart:auxv:read.
1539 qXfer:memory-map:read:
1540 Fetch a memory map from the remote stub, including information about
1541 RAM, ROM, and flash memory devices.
1546 Erase and program a flash memory device.
1548 * Removed remote packets
1551 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1552 used it, and only gdbserver implemented it.
1554 *** Changes in GDB 6.5
1558 Renesas M32C/M16C m32c-elf
1560 Morpho Technologies ms1 ms1-elf
1564 init-if-undefined Initialize a convenience variable, but
1565 only if it doesn't already have a value.
1567 The following commands are presently only implemented for native GNU/Linux:
1569 checkpoint Save a snapshot of the program state.
1571 restart <n> Return the program state to a
1572 previously saved state.
1574 info checkpoints List currently saved checkpoints.
1576 delete-checkpoint <n> Delete a previously saved checkpoint.
1578 set|show detach-on-fork Tell gdb whether to detach from a newly
1579 forked process, or to keep debugging it.
1581 info forks List forks of the user program that
1582 are available to be debugged.
1584 fork <n> Switch to debugging one of several
1585 forks of the user program that are
1586 available to be debugged.
1588 delete-fork <n> Delete a fork from the list of forks
1589 that are available to be debugged (and
1590 kill the forked process).
1592 detach-fork <n> Delete a fork from the list of forks
1593 that are available to be debugged (and
1594 allow the process to continue).
1598 Morpho Technologies ms2 ms1-elf
1600 * Improved Windows host support
1602 GDB now builds as a cross debugger hosted on i686-mingw32, including
1603 native console support, and remote communications using either
1604 network sockets or serial ports.
1606 * Improved Modula-2 language support
1608 GDB can now print most types in the Modula-2 syntax. This includes:
1609 basic types, set types, record types, enumerated types, range types,
1610 pointer types and ARRAY types. Procedure var parameters are correctly
1611 printed and hexadecimal addresses and character constants are also
1612 written in the Modula-2 syntax. Best results can be obtained by using
1613 GNU Modula-2 together with the -gdwarf-2 command line option.
1617 The ARM rdi-share module.
1619 The Netware NLM debug server.
1621 *** Changes in GDB 6.4
1623 * New native configurations
1625 OpenBSD/arm arm*-*-openbsd*
1626 OpenBSD/mips64 mips64-*-openbsd*
1630 Morpho Technologies ms1 ms1-elf
1632 * New command line options
1634 --batch-silent As for --batch, but totally silent.
1635 --return-child-result The debugger will exist with the same value
1636 the child (debugged) program exited with.
1637 --eval-command COMMAND, -ex COMMAND
1638 Execute a single GDB CLI command. This may be
1639 specified multiple times and in conjunction
1640 with the --command (-x) option.
1642 * Deprecated commands removed
1644 The following commands, that were deprecated in 2000, have been
1648 set|show arm disassembly-flavor set|show arm disassembler
1649 othernames set arm disassembler
1650 set|show remotedebug set|show debug remote
1651 set|show archdebug set|show debug arch
1652 set|show eventdebug set|show debug event
1655 * New BSD user-level threads support
1657 It is now possible to debug programs using the user-level threads
1658 library on OpenBSD and FreeBSD. Currently supported (target)
1661 FreeBSD/amd64 x86_64-*-freebsd*
1662 FreeBSD/i386 i386-*-freebsd*
1663 OpenBSD/i386 i386-*-openbsd*
1665 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1666 are not yet supported.
1668 * New support for Matsushita MN10300 w/sim added
1669 (Work in progress). mn10300-elf.
1671 * REMOVED configurations and files
1673 VxWorks and the XDR protocol *-*-vxworks
1674 Motorola MCORE mcore-*-*
1675 National Semiconductor NS32000 ns32k-*-*
1677 * New "set print array-indexes" command
1679 After turning this setting "on", GDB prints the index of each element
1680 when displaying arrays. The default is "off" to preserve the previous
1683 * VAX floating point support
1685 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1687 * User-defined command support
1689 In addition to using $arg0..$arg9 for argument passing, it is now possible
1690 to use $argc to determine now many arguments have been passed. See the
1691 section on user-defined commands in the user manual for more information.
1693 *** Changes in GDB 6.3:
1695 * New command line option
1697 GDB now accepts -l followed by a number to set the timeout for remote
1700 * GDB works with GCC -feliminate-dwarf2-dups
1702 GDB now supports a more compact representation of DWARF-2 debug
1703 information using DW_FORM_ref_addr references. These are produced
1704 by GCC with the option -feliminate-dwarf2-dups and also by some
1705 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1706 to use -feliminate-dwarf2-dups.
1708 * Internationalization
1710 When supported by the host system, GDB will be built with
1711 internationalization (libintl). The task of marking up the sources is
1712 continued, we're looking forward to our first translation.
1716 Initial support for debugging programs compiled with the GNAT
1717 implementation of the Ada programming language has been integrated
1718 into GDB. In this release, support is limited to expression evaluation.
1720 * New native configurations
1722 GNU/Linux/m32r m32r-*-linux-gnu
1726 GDB's remote protocol now includes support for the 'p' packet. This
1727 packet is used to fetch individual registers from a remote inferior.
1729 * END-OF-LIFE registers[] compatibility module
1731 GDB's internal register infrastructure has been completely rewritten.
1732 The new infrastructure making possible the implementation of key new
1733 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1736 GDB 6.3 will be the last release to include the the registers[]
1737 compatibility module that allowed out-of-date configurations to
1738 continue to work. This change directly impacts the following
1748 powerpc bdm protocol
1750 Unless there is activity to revive these configurations, they will be
1751 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1753 * OBSOLETE configurations and files
1755 Configurations that have been declared obsolete in this release have
1756 been commented out. Unless there is activity to revive these
1757 configurations, the next release of GDB will have their sources
1758 permanently REMOVED.
1767 *** Changes in GDB 6.2.1:
1769 * MIPS `break main; run' gave an heuristic-fence-post warning
1771 When attempting to run even a simple program, a warning about
1772 heuristic-fence-post being hit would be reported. This problem has
1775 * MIPS IRIX 'long double' crashed GDB
1777 When examining a long double variable, GDB would get a segmentation
1778 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1779 IRIX long double values).
1783 A bug in the VAX stack code was causing problems with the "next"
1784 command. This problem has been fixed.
1786 *** Changes in GDB 6.2:
1788 * Fix for ``many threads''
1790 On GNU/Linux systems that use the NPTL threads library, a program
1791 rapidly creating and deleting threads would confuse GDB leading to the
1794 ptrace: No such process.
1795 thread_db_get_info: cannot get thread info: generic error
1797 This problem has been fixed.
1799 * "-async" and "-noasync" options removed.
1801 Support for the broken "-noasync" option has been removed (it caused
1804 * New ``start'' command.
1806 This command runs the program until the begining of the main procedure.
1808 * New BSD Kernel Data Access Library (libkvm) interface
1810 Using ``target kvm'' it is now possible to debug kernel core dumps and
1811 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1812 platforms. Currently supported (native-only) configurations are:
1814 FreeBSD/amd64 x86_64-*-freebsd*
1815 FreeBSD/i386 i?86-*-freebsd*
1816 NetBSD/i386 i?86-*-netbsd*
1817 NetBSD/m68k m68*-*-netbsd*
1818 NetBSD/sparc sparc-*-netbsd*
1819 OpenBSD/amd64 x86_64-*-openbsd*
1820 OpenBSD/i386 i?86-*-openbsd*
1821 OpenBSD/m68k m68*-openbsd*
1822 OpenBSD/sparc sparc-*-openbsd*
1824 * Signal trampoline code overhauled
1826 Many generic problems with GDB's signal handling code have been fixed.
1827 These include: backtraces through non-contiguous stacks; recognition
1828 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1829 call; backtrace through a signal trampoline; step into and out of
1830 signal handlers; and single-stepping in the signal trampoline.
1832 Please note that kernel bugs are a limiting factor here. These
1833 features have been shown to work on an s390 GNU/Linux system that
1834 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1836 * Cygwin support for DWARF 2 added.
1838 * New native configurations
1840 GNU/Linux/hppa hppa*-*-linux*
1841 OpenBSD/hppa hppa*-*-openbsd*
1842 OpenBSD/m68k m68*-*-openbsd*
1843 OpenBSD/m88k m88*-*-openbsd*
1844 OpenBSD/powerpc powerpc-*-openbsd*
1845 NetBSD/vax vax-*-netbsd*
1846 OpenBSD/vax vax-*-openbsd*
1848 * END-OF-LIFE frame compatibility module
1850 GDB's internal frame infrastructure has been completely rewritten.
1851 The new infrastructure making it possible to support key new features
1852 including DWARF 2 Call Frame Information. To aid in the task of
1853 migrating old configurations to this new infrastructure, a
1854 compatibility module, that allowed old configurations to continue to
1855 work, was also included.
1857 GDB 6.2 will be the last release to include this frame compatibility
1858 module. This change directly impacts the following configurations:
1868 Unless there is activity to revive these configurations, they will be
1869 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1871 * REMOVED configurations and files
1873 Sun 3, running SunOS 3 m68*-*-sunos3*
1874 Sun 3, running SunOS 4 m68*-*-sunos4*
1875 Sun 2, running SunOS 3 m68000-*-sunos3*
1876 Sun 2, running SunOS 4 m68000-*-sunos4*
1877 Motorola 680x0 running LynxOS m68*-*-lynxos*
1878 AT&T 3b1/Unix pc m68*-att-*
1879 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1880 decstation mips-dec-* mips-little-*
1881 riscos mips-*-riscos* mips-*-sysv*
1882 sonymips mips-sony-*
1883 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1885 *** Changes in GDB 6.1.1:
1887 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1889 The TUI (Text-mode User Interface) is now built as part of a default
1890 GDB configuration. It is enabled by either selecting the TUI with the
1891 command line option "-i=tui" or by running the separate "gdbtui"
1892 program. For more information on the TUI, see the manual "Debugging
1895 * Pending breakpoint support (also included in GDB 6.1)
1897 Support has been added to allow you to specify breakpoints in shared
1898 libraries that have not yet been loaded. If a breakpoint location
1899 cannot be found, and the "breakpoint pending" option is set to auto,
1900 GDB queries you if you wish to make the breakpoint pending on a future
1901 shared-library load. If and when GDB resolves the breakpoint symbol,
1902 the pending breakpoint is removed as one or more regular breakpoints
1905 Pending breakpoints are very useful for GCJ Java debugging.
1907 * Fixed ISO-C build problems
1909 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1910 non ISO-C code that stopped them being built using a more strict ISO-C
1911 compiler (e.g., IBM's C compiler).
1913 * Fixed build problem on IRIX 5
1915 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1916 wasn't able to compile compile on an IRIX 5 system.
1918 * Added execute permission to gdb/gdbserver/configure
1920 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1921 permission. This bug would cause configure to fail on a number of
1922 systems (Solaris, IRIX). Ref: server/519.
1924 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1926 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1927 has been updated to use constant array sizes.
1929 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1931 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1932 its generated DWARF Call Frame Info. This encoding was causing GDB to
1933 panic, that panic has been fixed. Ref: gdb/1628.
1935 * Fixed a problem when examining parameters in shared library code.
1937 When examining parameters in optimized shared library code generated
1938 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1939 not available''. GDB now correctly displays the variable's value.
1941 *** Changes in GDB 6.1:
1943 * Removed --with-mmalloc
1945 Support for the mmalloc memory manager has been removed, as it
1946 conflicted with the internal gdb byte cache.
1948 * Changes in AMD64 configurations
1950 The AMD64 target now includes the %cs and %ss registers. As a result
1951 the AMD64 remote protocol has changed; this affects the floating-point
1952 and SSE registers. If you rely on those registers for your debugging,
1953 you should upgrade gdbserver on the remote side.
1955 * Revised SPARC target
1957 The SPARC target has been completely revised, incorporating the
1958 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1959 support for LynxOS and SunOS 4 has been dropped. Calling functions
1960 from within GDB on operating systems with a non-executable stack
1961 (Solaris, OpenBSD) now works.
1965 GDB has a new C++ demangler which does a better job on the mangled
1966 names generated by current versions of g++. It also runs faster, so
1967 with this and other changes gdb should now start faster on large C++
1970 * DWARF 2 Location Expressions
1972 GDB support for location expressions has been extended to support function
1973 arguments and frame bases. Older versions of GDB could crash when they
1976 * C++ nested types and namespaces
1978 GDB's support for nested types and namespaces in C++ has been
1979 improved, especially if you use the DWARF 2 debugging format. (This
1980 is the default for recent versions of GCC on most platforms.)
1981 Specifically, if you have a class "Inner" defined within a class or
1982 namespace "Outer", then GDB realizes that the class's name is
1983 "Outer::Inner", not simply "Inner". This should greatly reduce the
1984 frequency of complaints about not finding RTTI symbols. In addition,
1985 if you are stopped at inside of a function defined within a namespace,
1986 GDB modifies its name lookup accordingly.
1988 * New native configurations
1990 NetBSD/amd64 x86_64-*-netbsd*
1991 OpenBSD/amd64 x86_64-*-openbsd*
1992 OpenBSD/alpha alpha*-*-openbsd*
1993 OpenBSD/sparc sparc-*-openbsd*
1994 OpenBSD/sparc64 sparc64-*-openbsd*
1996 * New debugging protocols
1998 M32R with SDI protocol m32r-*-elf*
2000 * "set prompt-escape-char" command deleted.
2002 The command "set prompt-escape-char" has been deleted. This command,
2003 and its very obscure effet on GDB's prompt, was never documented,
2004 tested, nor mentioned in the NEWS file.
2006 * OBSOLETE configurations and files
2008 Configurations that have been declared obsolete in this release have
2009 been commented out. Unless there is activity to revive these
2010 configurations, the next release of GDB will have their sources
2011 permanently REMOVED.
2013 Sun 3, running SunOS 3 m68*-*-sunos3*
2014 Sun 3, running SunOS 4 m68*-*-sunos4*
2015 Sun 2, running SunOS 3 m68000-*-sunos3*
2016 Sun 2, running SunOS 4 m68000-*-sunos4*
2017 Motorola 680x0 running LynxOS m68*-*-lynxos*
2018 AT&T 3b1/Unix pc m68*-att-*
2019 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2020 decstation mips-dec-* mips-little-*
2021 riscos mips-*-riscos* mips-*-sysv*
2022 sonymips mips-sony-*
2023 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2025 * REMOVED configurations and files
2027 SGI Irix-4.x mips-sgi-irix4 or iris4
2028 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2029 Z8000 simulator z8k-zilog-none or z8ksim
2030 Matsushita MN10200 w/simulator mn10200-*-*
2031 H8/500 simulator h8500-hitachi-hms or h8500hms
2032 HP/PA running BSD hppa*-*-bsd*
2033 HP/PA running OSF/1 hppa*-*-osf*
2034 HP/PA Pro target hppa*-*-pro*
2035 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2036 386BSD i[3456]86-*-bsd*
2037 Sequent family i[3456]86-sequent-sysv4*
2038 i[3456]86-sequent-sysv*
2039 i[3456]86-sequent-bsd*
2040 SPARC running LynxOS sparc-*-lynxos*
2041 SPARC running SunOS 4 sparc-*-sunos4*
2042 Tsqware Sparclet sparclet-*-*
2043 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2045 *** Changes in GDB 6.0:
2049 Support for debugging the Objective-C programming language has been
2050 integrated into GDB.
2052 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2054 DWARF 2's Call Frame Information makes available compiler generated
2055 information that more exactly describes the program's run-time stack.
2056 By using this information, GDB is able to provide more robust stack
2059 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2060 have been updated to use a new backtrace mechanism which includes
2061 DWARF 2 CFI support.
2065 GDB's remote protocol has been extended to include support for hosted
2066 file I/O (where the remote target uses GDB's file system). See GDB's
2067 remote protocol documentation for details.
2069 * All targets using the new architecture framework.
2071 All of GDB's targets have been updated to use the new internal
2072 architecture framework. The way is now open for future GDB releases
2073 to include cross-architecture native debugging support (i386 on amd64,
2076 * GNU/Linux's Thread Local Storage (TLS)
2078 GDB now includes support for for the GNU/Linux implementation of
2079 per-thread variables.
2081 * GNU/Linux's Native POSIX Thread Library (NPTL)
2083 GDB's thread code has been updated to work with either the new
2084 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2086 * Separate debug info.
2088 GDB, in conjunction with BINUTILS, now supports a mechanism for
2089 automatically loading debug information from a separate file. Instead
2090 of shipping full debug and non-debug versions of system libraries,
2091 system integrators can now instead ship just the stripped libraries
2092 and optional debug files.
2094 * DWARF 2 Location Expressions
2096 DWARF 2 Location Expressions allow the compiler to more completely
2097 describe the location of variables (even in optimized code) to the
2100 GDB now includes preliminary support for location expressions (support
2101 for DW_OP_piece is still missing).
2105 A number of long standing bugs that caused GDB to die while starting a
2106 Java application have been fixed. GDB's Java support is now
2107 considered "useable".
2109 * GNU/Linux support for fork, vfork, and exec.
2111 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2112 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2115 * GDB supports logging output to a file
2117 There are two new commands, "set logging" and "show logging", which can be
2118 used to capture GDB's output to a file.
2120 * The meaning of "detach" has changed for gdbserver
2122 The "detach" command will now resume the application, as documented. To
2123 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2126 * d10v, m68hc11 `regs' command deprecated
2128 The `info registers' command has been updated so that it displays the
2129 registers using a format identical to the old `regs' command.
2133 A new command, "maint set profile on/off", has been added. This command can
2134 be used to enable or disable profiling while running GDB, to profile a
2135 session or a set of commands. In addition there is a new configure switch,
2136 "--enable-profiling", which will cause GDB to be compiled with profiling
2137 data, for more informative profiling results.
2139 * Default MI syntax changed to "mi2".
2141 The default MI (machine interface) syntax, enabled by the command line
2142 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2143 "mi1", can be enabled by specifying the option "-i=mi1".
2145 Support for the original "mi0" syntax (included in GDB 5.0) has been
2148 Fix for gdb/192: removed extraneous space when displaying frame level.
2149 Fix for gdb/672: update changelist is now output in mi list format.
2150 Fix for gdb/702: a -var-assign that updates the value now shows up
2151 in a subsequent -var-update.
2153 * New native configurations.
2155 FreeBSD/amd64 x86_64-*-freebsd*
2157 * Multi-arched targets.
2159 HP/PA HPUX11 hppa*-*-hpux*
2160 Renesas M32R/D w/simulator m32r-*-elf*
2162 * OBSOLETE configurations and files
2164 Configurations that have been declared obsolete in this release have
2165 been commented out. Unless there is activity to revive these
2166 configurations, the next release of GDB will have their sources
2167 permanently REMOVED.
2169 Z8000 simulator z8k-zilog-none or z8ksim
2170 Matsushita MN10200 w/simulator mn10200-*-*
2171 H8/500 simulator h8500-hitachi-hms or h8500hms
2172 HP/PA running BSD hppa*-*-bsd*
2173 HP/PA running OSF/1 hppa*-*-osf*
2174 HP/PA Pro target hppa*-*-pro*
2175 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2176 Sequent family i[3456]86-sequent-sysv4*
2177 i[3456]86-sequent-sysv*
2178 i[3456]86-sequent-bsd*
2179 Tsqware Sparclet sparclet-*-*
2180 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2182 * REMOVED configurations and files
2185 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2186 IBM AIX PS/2 i[3456]86-*-aix
2187 i386 running Mach 3.0 i[3456]86-*-mach3*
2188 i386 running Mach i[3456]86-*-mach*
2189 i386 running OSF/1 i[3456]86-*osf1mk*
2190 HP/Apollo 68k Family m68*-apollo*-sysv*,
2192 m68*-hp-bsd*, m68*-hp-hpux*
2193 Argonaut Risc Chip (ARC) arc-*-*
2194 Mitsubishi D30V d30v-*-*
2195 Fujitsu FR30 fr30-*-elf*
2196 OS/9000 i[34]86-*-os9k
2197 I960 with MON960 i960-*-coff
2199 * MIPS $fp behavior changed
2201 The convenience variable $fp, for the MIPS, now consistently returns
2202 the address of the current frame's base. Previously, depending on the
2203 context, $fp could refer to either $sp or the current frame's base
2204 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2205 The GNU Source-Level Debugger''.
2207 *** Changes in GDB 5.3:
2209 * GNU/Linux shared library multi-threaded performance improved.
2211 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2212 `/proc', in preference to `ptrace' for memory reads. This may result
2213 in an improvement in the start-up time of multi-threaded, shared
2214 library applications when run under GDB. One GDB user writes: ``loads
2215 shared libs like mad''.
2217 * ``gdbserver'' now supports multi-threaded applications on some targets
2219 Support for debugging multi-threaded applications which use
2220 the GNU/Linux LinuxThreads package has been added for
2221 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2222 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2224 * GDB now supports C/C++ preprocessor macros.
2226 GDB now expands preprocessor macro invocations in C/C++ expressions,
2227 and provides various commands for showing macro definitions and how
2230 The new command `macro expand EXPRESSION' expands any macro
2231 invocations in expression, and shows the result.
2233 The new command `show macro MACRO-NAME' shows the definition of the
2234 macro named MACRO-NAME, and where it was defined.
2236 Most compilers don't include information about macros in the debugging
2237 information by default. In GCC 3.1, for example, you need to compile
2238 your program with the options `-gdwarf-2 -g3'. If the macro
2239 information is present in the executable, GDB will read it.
2241 * Multi-arched targets.
2243 DEC Alpha (partial) alpha*-*-*
2244 DEC VAX (partial) vax-*-*
2246 National Semiconductor NS32000 (partial) ns32k-*-*
2247 Motorola 68000 (partial) m68k-*-*
2248 Motorola MCORE mcore-*-*
2252 Fujitsu FRV architecture added by Red Hat frv*-*-*
2255 * New native configurations
2257 Alpha NetBSD alpha*-*-netbsd*
2258 SH NetBSD sh*-*-netbsdelf*
2259 MIPS NetBSD mips*-*-netbsd*
2260 UltraSPARC NetBSD sparc64-*-netbsd*
2262 * OBSOLETE configurations and files
2264 Configurations that have been declared obsolete in this release have
2265 been commented out. Unless there is activity to revive these
2266 configurations, the next release of GDB will have their sources
2267 permanently REMOVED.
2269 Mitsubishi D30V d30v-*-*
2270 OS/9000 i[34]86-*-os9k
2271 IBM AIX PS/2 i[3456]86-*-aix
2272 Fujitsu FR30 fr30-*-elf*
2273 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2274 Argonaut Risc Chip (ARC) arc-*-*
2275 i386 running Mach 3.0 i[3456]86-*-mach3*
2276 i386 running Mach i[3456]86-*-mach*
2277 i386 running OSF/1 i[3456]86-*osf1mk*
2278 HP/Apollo 68k Family m68*-apollo*-sysv*,
2280 m68*-hp-bsd*, m68*-hp-hpux*
2281 I960 with MON960 i960-*-coff
2283 * OBSOLETE languages
2285 CHILL, a Pascal like language used by telecommunications companies.
2287 * REMOVED configurations and files
2289 AMD 29k family via UDI a29k-amd-udi, udi29k
2290 A29K VxWorks a29k-*-vxworks
2291 AMD 29000 embedded, using EBMON a29k-none-none
2292 AMD 29000 embedded with COFF a29k-none-coff
2293 AMD 29000 embedded with a.out a29k-none-aout
2295 testsuite/gdb.hp/gdb.threads-hp/ directory
2297 * New command "set max-user-call-depth <nnn>"
2299 This command allows the user to limit the call depth of user-defined
2300 commands. The default is 1024.
2302 * Changes in FreeBSD/i386 native debugging.
2304 Support for the "generate-core-file" has been added.
2306 * New commands "dump", "append", and "restore".
2308 These commands allow data to be copied from target memory
2309 to a bfd-format or binary file (dump and append), and back
2310 from a file into memory (restore).
2312 * Improved "next/step" support on multi-processor Alpha Tru64.
2314 The previous single-step mechanism could cause unpredictable problems,
2315 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2316 of a software single-step mechanism prevents this.
2318 *** Changes in GDB 5.2.1:
2326 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2327 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2328 Fix, by Joel Brobecker imported from mainline.
2330 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2331 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2332 Fix, by Fred Fish, imported from mainline.
2334 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2335 Surprisingly enough, it works now.
2336 By Michal Ludvig, imported from mainline.
2338 i386 hardware watchpoint support:
2339 avoid misses on second run for some targets.
2340 By Pierre Muller, imported from mainline.
2342 *** Changes in GDB 5.2:
2344 * New command "set trust-readonly-sections on[off]".
2346 This command is a hint that tells gdb that read-only sections
2347 really are read-only (ie. that their contents will not change).
2348 In this mode, gdb will go to the object file rather than the
2349 target to read memory from read-only sections (such as ".text").
2350 This can be a significant performance improvement on some
2351 (notably embedded) targets.
2353 * New command "generate-core-file" (or "gcore").
2355 This new gdb command allows the user to drop a core file of the child
2356 process state at any time. So far it's been implemented only for
2357 GNU/Linux and Solaris, but should be relatively easily ported to other
2358 hosts. Argument is core file name (defaults to core.<pid>).
2360 * New command line option
2362 GDB now accepts --pid or -p followed by a process id.
2364 * Change in command line behavior -- corefiles vs. process ids.
2366 There is a subtle behavior in the way in which GDB handles
2367 command line arguments. The first non-flag argument is always
2368 a program to debug, but the second non-flag argument may either
2369 be a corefile or a process id. Previously, GDB would attempt to
2370 open the second argument as a corefile, and if that failed, would
2371 issue a superfluous error message and then attempt to attach it as
2372 a process. Now, if the second argument begins with a non-digit,
2373 it will be treated as a corefile. If it begins with a digit,
2374 GDB will attempt to attach it as a process, and if no such process
2375 is found, will then attempt to open it as a corefile.
2377 * Changes in ARM configurations.
2379 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2380 configuration is fully multi-arch.
2382 * New native configurations
2384 ARM NetBSD arm*-*-netbsd*
2385 x86 OpenBSD i[3456]86-*-openbsd*
2386 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2387 Sparc64 running FreeBSD sparc64-*-freebsd*
2391 Sanyo XStormy16 xstormy16-elf
2393 * OBSOLETE configurations and files
2395 Configurations that have been declared obsolete in this release have
2396 been commented out. Unless there is activity to revive these
2397 configurations, the next release of GDB will have their sources
2398 permanently REMOVED.
2400 AMD 29k family via UDI a29k-amd-udi, udi29k
2401 A29K VxWorks a29k-*-vxworks
2402 AMD 29000 embedded, using EBMON a29k-none-none
2403 AMD 29000 embedded with COFF a29k-none-coff
2404 AMD 29000 embedded with a.out a29k-none-aout
2406 testsuite/gdb.hp/gdb.threads-hp/ directory
2408 * REMOVED configurations and files
2410 TI TMS320C80 tic80-*-*
2412 PowerPC Solaris powerpcle-*-solaris*
2413 PowerPC Windows NT powerpcle-*-cygwin32
2414 PowerPC Netware powerpc-*-netware*
2415 Harris/CXUX m88k m88*-harris-cxux*
2416 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2417 ns32k-utek-sysv* ns32k-utek-*
2418 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2419 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2420 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2421 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2422 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2424 * Changes to command line processing
2426 The new `--args' feature can be used to specify command-line arguments
2427 for the inferior from gdb's command line.
2429 * Changes to key bindings
2431 There is a new `operate-and-get-next' function bound to `C-o'.
2433 *** Changes in GDB 5.1.1
2435 Fix compile problem on DJGPP.
2437 Fix a problem with floating-point registers on the i386 being
2440 Fix to stop GDB crashing on .debug_str debug info.
2442 Numerous documentation fixes.
2444 Numerous testsuite fixes.
2446 *** Changes in GDB 5.1:
2448 * New native configurations
2450 Alpha FreeBSD alpha*-*-freebsd*
2451 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2452 MIPS GNU/Linux mips*-*-linux*
2453 MIPS SGI Irix 6.x mips*-sgi-irix6*
2454 ia64 AIX ia64-*-aix*
2455 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2459 Motorola 68HC11 and 68HC12 m68hc11-elf
2461 UltraSparc running GNU/Linux sparc64-*-linux*
2463 * OBSOLETE configurations and files
2465 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2466 Harris/CXUX m88k m88*-harris-cxux*
2467 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2468 ns32k-utek-sysv* ns32k-utek-*
2469 TI TMS320C80 tic80-*-*
2471 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2472 PowerPC Solaris powerpcle-*-solaris*
2473 PowerPC Windows NT powerpcle-*-cygwin32
2474 PowerPC Netware powerpc-*-netware*
2475 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2476 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2477 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2478 Apple Macintosh (MPW) host N/A
2480 stuff.c (Program to stuff files into a specially prepared space in kdb)
2481 kdb-start.c (Main loop for the standalone kernel debugger)
2483 Configurations that have been declared obsolete in this release have
2484 been commented out. Unless there is activity to revive these
2485 configurations, the next release of GDB will have their sources
2486 permanently REMOVED.
2488 * REMOVED configurations and files
2490 Altos 3068 m68*-altos-*
2491 Convex c1-*-*, c2-*-*
2493 ARM RISCix arm-*-* (as host)
2497 * GDB has been converted to ISO C.
2499 GDB's source code has been converted to ISO C. In particular, the
2500 sources are fully protoized, and rely on standard headers being
2505 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2507 * The MI enabled by default.
2509 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2510 revised and enabled by default. Packages which use GDB as a debugging
2511 engine behind a UI or another front end are encouraged to switch to
2512 using the GDB/MI interface, instead of the old annotations interface
2513 which is now deprecated.
2515 * Support for debugging Pascal programs.
2517 GDB now includes support for debugging Pascal programs. The following
2518 main features are supported:
2520 - Pascal-specific data types such as sets;
2522 - automatic recognition of Pascal sources based on file-name
2525 - Pascal-style display of data types, variables, and functions;
2527 - a Pascal expression parser.
2529 However, some important features are not yet supported.
2531 - Pascal string operations are not supported at all;
2533 - there are some problems with boolean types;
2535 - Pascal type hexadecimal constants are not supported
2536 because they conflict with the internal variables format;
2538 - support for Pascal objects and classes is not full yet;
2540 - unlike Pascal, GDB is case-sensitive for symbol names.
2542 * Changes in completion.
2544 Commands such as `shell', `run' and `set args', which pass arguments
2545 to inferior programs, now complete on file names, similar to what
2546 users expect at the shell prompt.
2548 Commands which accept locations, such as `disassemble', `print',
2549 `breakpoint', `until', etc. now complete on filenames as well as
2550 program symbols. Thus, if you type "break foob TAB", and the source
2551 files linked into the programs include `foobar.c', that file name will
2552 be one of the candidates for completion. However, file names are not
2553 considered for completion after you typed a colon that delimits a file
2554 name from a name of a function in that file, as in "break foo.c:bar".
2556 `set demangle-style' completes on available demangling styles.
2558 * New platform-independent commands:
2560 It is now possible to define a post-hook for a command as well as a
2561 hook that runs before the command. For more details, see the
2562 documentation of `hookpost' in the GDB manual.
2564 * Changes in GNU/Linux native debugging.
2566 Support for debugging multi-threaded programs has been completely
2567 revised for all platforms except m68k and sparc. You can now debug as
2568 many threads as your system allows you to have.
2570 Attach/detach is supported for multi-threaded programs.
2572 Support for SSE registers was added for x86. This doesn't work for
2573 multi-threaded programs though.
2575 * Changes in MIPS configurations.
2577 Multi-arch support is enabled for all MIPS configurations.
2579 GDB can now be built as native debugger on SGI Irix 6.x systems for
2580 debugging n32 executables. (Debugging 64-bit executables is not yet
2583 * Unified support for hardware watchpoints in all x86 configurations.
2585 Most (if not all) native x86 configurations support hardware-assisted
2586 breakpoints and watchpoints in a unified manner. This support
2587 implements debug register sharing between watchpoints, which allows to
2588 put a virtually infinite number of watchpoints on the same address,
2589 and also supports watching regions up to 16 bytes with several debug
2592 The new maintenance command `maintenance show-debug-regs' toggles
2593 debugging print-outs in functions that insert, remove, and test
2594 watchpoints and hardware breakpoints.
2596 * Changes in the DJGPP native configuration.
2598 New command ``info dos sysinfo'' displays assorted information about
2599 the CPU, OS, memory, and DPMI server.
2601 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2602 display information about segment descriptors stored in GDT, LDT, and
2605 New commands ``info dos pde'' and ``info dos pte'' display entries
2606 from Page Directory and Page Tables (for now works with CWSDPMI only).
2607 New command ``info dos address-pte'' displays the Page Table entry for
2608 a given linear address.
2610 GDB can now pass command lines longer than 126 characters to the
2611 program being debugged (requires an update to the libdbg.a library
2612 which is part of the DJGPP development kit).
2614 DWARF2 debug info is now supported.
2616 It is now possible to `step' and `next' through calls to `longjmp'.
2618 * Changes in documentation.
2620 All GDB documentation was converted to GFDL, the GNU Free
2621 Documentation License.
2623 Tracepoints-related commands are now fully documented in the GDB
2626 TUI, the Text-mode User Interface, is now documented in the manual.
2628 Tracepoints-related commands are now fully documented in the GDB
2631 The "GDB Internals" manual now has an index. It also includes
2632 documentation of `ui_out' functions, GDB coding standards, x86
2633 hardware watchpoints, and memory region attributes.
2635 * GDB's version number moved to ``version.in''
2637 The Makefile variable VERSION has been replaced by the file
2638 ``version.in''. People creating GDB distributions should update the
2639 contents of this file.
2643 GUD support is now a standard part of the EMACS distribution.
2645 *** Changes in GDB 5.0:
2647 * Improved support for debugging FP programs on x86 targets
2649 Unified and much-improved support for debugging floating-point
2650 programs on all x86 targets. In particular, ``info float'' now
2651 displays the FP registers in the same format on all x86 targets, with
2652 greater level of detail.
2654 * Improvements and bugfixes in hardware-assisted watchpoints
2656 It is now possible to watch array elements, struct members, and
2657 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2658 on x86 targets no longer erroneously trigger when the address is
2661 * Improvements in the native DJGPP version of GDB
2663 The distribution now includes all the scripts and auxiliary files
2664 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2665 machines ``out of the box''.
2667 The DJGPP version can now debug programs that use signals. It is
2668 possible to catch signals that happened in the debuggee, deliver
2669 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2670 would kill the program being debugged.) Programs that hook hardware
2671 interrupts (keyboard, timer, etc.) can also be debugged.
2673 It is now possible to debug DJGPP programs that redirect their
2674 standard handles or switch them to raw (as opposed to cooked) mode, or
2675 even close them. The command ``run < foo > bar'' works as expected,
2676 and ``info terminal'' reports useful information about the debuggee's
2677 terminal, including raw/cooked mode, redirection, etc.
2679 The DJGPP version now uses termios functions for console I/O, which
2680 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2683 DOS-style file names with drive letters are now fully supported by
2686 It is now possible to debug DJGPP programs that switch their working
2687 directory. It is also possible to rerun the debuggee any number of
2688 times without restarting GDB; thus, you can use the same setup,
2689 breakpoints, etc. for many debugging sessions.
2691 * New native configurations
2693 ARM GNU/Linux arm*-*-linux*
2694 PowerPC GNU/Linux powerpc-*-linux*
2698 Motorola MCore mcore-*-*
2699 x86 VxWorks i[3456]86-*-vxworks*
2700 PowerPC VxWorks powerpc-*-vxworks*
2701 TI TMS320C80 tic80-*-*
2703 * OBSOLETE configurations
2705 Altos 3068 m68*-altos-*
2706 Convex c1-*-*, c2-*-*
2708 ARM RISCix arm-*-* (as host)
2711 Configurations that have been declared obsolete will be commented out,
2712 but the code will be left in place. If there is no activity to revive
2713 these configurations before the next release of GDB, the sources will
2714 be permanently REMOVED.
2716 * Gould support removed
2718 Support for the Gould PowerNode and NP1 has been removed.
2720 * New features for SVR4
2722 On SVR4 native platforms (such as Solaris), if you attach to a process
2723 without first loading a symbol file, GDB will now attempt to locate and
2724 load symbols from the running process's executable file.
2726 * Many C++ enhancements
2728 C++ support has been greatly improved. Overload resolution now works properly
2729 in almost all cases. RTTI support is on the way.
2731 * Remote targets can connect to a sub-program
2733 A popen(3) style serial-device has been added. This device starts a
2734 sub-process (such as a stand-alone simulator) and then communicates
2735 with that. The sub-program to run is specified using the syntax
2736 ``|<program> <args>'' vis:
2738 (gdb) set remotedebug 1
2739 (gdb) target extended-remote |mn10300-elf-sim program-args
2741 * MIPS 64 remote protocol
2743 A long standing bug in the mips64 remote protocol where by GDB
2744 expected certain 32 bit registers (ex SR) to be transfered as 32
2745 instead of 64 bits has been fixed.
2747 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2748 added to provide backward compatibility with older versions of GDB.
2750 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2752 The command ``set remotebinarydownload'' command has been replaced by
2753 ``set remote X-packet''. Other commands in ``set remote'' family
2754 include ``set remote P-packet''.
2756 * Breakpoint commands accept ranges.
2758 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2759 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2760 ``tracepoint passcount'' also accepts a range of tracepoints.
2762 * ``apropos'' command added.
2764 The ``apropos'' command searches through command names and
2765 documentation strings, printing out matches, making it much easier to
2766 try to find a command that does what you are looking for.
2770 A new machine oriented interface (MI) has been added to GDB. This
2771 interface is designed for debug environments running GDB as a separate
2772 process. This is part of the long term libGDB project. See the
2773 "GDB/MI" chapter of the GDB manual for further information. It can be
2774 enabled by configuring with:
2776 .../configure --enable-gdbmi
2778 *** Changes in GDB-4.18:
2780 * New native configurations
2782 HP-UX 10.20 hppa*-*-hpux10.20
2783 HP-UX 11.x hppa*-*-hpux11.0*
2784 M68K GNU/Linux m68*-*-linux*
2788 Fujitsu FR30 fr30-*-elf*
2789 Intel StrongARM strongarm-*-*
2790 Mitsubishi D30V d30v-*-*
2792 * OBSOLETE configurations
2794 Gould PowerNode, NP1 np1-*-*, pn-*-*
2796 Configurations that have been declared obsolete will be commented out,
2797 but the code will be left in place. If there is no activity to revive
2798 these configurations before the next release of GDB, the sources will
2799 be permanently REMOVED.
2803 As a compatibility experiment, GDB's source files buildsym.h and
2804 buildsym.c have been converted to pure standard C, no longer
2805 containing any K&R compatibility code. We believe that all systems in
2806 use today either come with a standard C compiler, or have a GCC port
2807 available. If this is not true, please report the affected
2808 configuration to bug-gdb@gnu.org immediately. See the README file for
2809 information about getting a standard C compiler if you don't have one
2814 GDB now uses readline 2.2.
2816 * set extension-language
2818 You can now control the mapping between filename extensions and source
2819 languages by using the `set extension-language' command. For instance,
2820 you can ask GDB to treat .c files as C++ by saying
2821 set extension-language .c c++
2822 The command `info extensions' lists all of the recognized extensions
2823 and their associated languages.
2825 * Setting processor type for PowerPC and RS/6000
2827 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2828 you can use the `set processor' command to specify what variant of the
2829 PowerPC family you are debugging. The command
2833 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2834 following PowerPC and RS6000 variants:
2836 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2837 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2839 403GC IBM PowerPC 403GC
2840 505 Motorola PowerPC 505
2841 860 Motorola PowerPC 860 or 850
2842 601 Motorola PowerPC 601
2843 602 Motorola PowerPC 602
2844 603 Motorola/IBM PowerPC 603 or 603e
2845 604 Motorola PowerPC 604 or 604e
2846 750 Motorola/IBM PowerPC 750 or 750
2848 At the moment, this command just tells GDB what to name the
2849 special-purpose processor registers. Since almost all the affected
2850 registers are inaccessible to user-level programs, this command is
2851 only useful for remote debugging in its present form.
2855 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2856 more extensive support for HP-UX. Added features include shared
2857 library support, kernel threads and hardware watchpoints for 11.00,
2858 support for HP's ANSI C and C++ compilers, and a compatibility mode
2859 for xdb and dbx commands.
2863 HP's donation includes the new concept of catchpoints, which is a
2864 generalization of the old catch command. On HP-UX, it is now possible
2865 to catch exec, fork, and vfork, as well as library loading.
2867 This means that the existing catch command has changed; its first
2868 argument now specifies the type of catch to be set up. See the
2869 output of "help catch" for a list of catchpoint types.
2871 * Debugging across forks
2873 On HP-UX, you can choose which process to debug when a fork() happens
2878 HP has donated a curses-based terminal user interface (TUI). To get
2879 it, build with --enable-tui. Although this can be enabled for any
2880 configuration, at present it only works for native HP debugging.
2882 * GDB remote protocol additions
2884 A new protocol packet 'X' that writes binary data is now available.
2885 Default behavior is to try 'X', then drop back to 'M' if the stub
2886 fails to respond. The settable variable `remotebinarydownload'
2887 allows explicit control over the use of 'X'.
2889 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2890 full 64-bit address. The command
2892 set remoteaddresssize 32
2894 can be used to revert to the old behaviour. For existing remote stubs
2895 the change should not be noticed, as the additional address information
2898 In order to assist in debugging stubs, you may use the maintenance
2899 command `packet' to send any text string to the stub. For instance,
2901 maint packet heythere
2903 sends the packet "$heythere#<checksum>". Note that it is very easy to
2904 disrupt a debugging session by sending the wrong packet at the wrong
2907 The compare-sections command allows you to compare section data on the
2908 target to what is in the executable file without uploading or
2909 downloading, by comparing CRC checksums.
2911 * Tracing can collect general expressions
2913 You may now collect general expressions at tracepoints. This requires
2914 further additions to the target-side stub; see tracepoint.c and
2915 doc/agentexpr.texi for further details.
2917 * mask-address variable for Mips
2919 For Mips targets, you may control the zeroing of the upper 32 bits of
2920 a 64-bit address by entering `set mask-address on'. This is mainly
2921 of interest to users of embedded R4xxx and R5xxx processors.
2923 * Higher serial baud rates
2925 GDB's serial code now allows you to specify baud rates 57600, 115200,
2926 230400, and 460800 baud. (Note that your host system may not be able
2927 to achieve all of these rates.)
2931 The i960 configuration now includes an initial implementation of a
2932 builtin simulator, contributed by Jim Wilson.
2935 *** Changes in GDB-4.17:
2937 * New native configurations
2939 Alpha GNU/Linux alpha*-*-linux*
2940 Unixware 2.x i[3456]86-unixware2*
2941 Irix 6.x mips*-sgi-irix6*
2942 PowerPC GNU/Linux powerpc-*-linux*
2943 PowerPC Solaris powerpcle-*-solaris*
2944 Sparc GNU/Linux sparc-*-linux*
2945 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2949 Argonaut Risc Chip (ARC) arc-*-*
2950 Hitachi H8/300S h8300*-*-*
2951 Matsushita MN10200 w/simulator mn10200-*-*
2952 Matsushita MN10300 w/simulator mn10300-*-*
2953 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2954 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2955 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2956 Mitsubishi D10V w/simulator d10v-*-*
2957 Mitsubishi M32R/D w/simulator m32r-*-elf*
2958 Tsqware Sparclet sparclet-*-*
2959 NEC V850 w/simulator v850-*-*
2961 * New debugging protocols
2963 ARM with RDI protocol arm*-*-*
2964 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2965 DDB and LSI variants of PMON protocol mips*-*-*
2966 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2967 PowerPC with SDS protocol powerpc{,le}-*-eabi
2968 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2972 All configurations can now understand and use the DWARF 2 debugging
2973 format. The choice is automatic, if the symbol file contains DWARF 2
2978 GDB now includes basic Java language support. This support is
2979 only useful with Java compilers that produce native machine code.
2981 * solib-absolute-prefix and solib-search-path
2983 For SunOS and SVR4 shared libraries, you may now set the prefix for
2984 loading absolute shared library symbol files, and the search path for
2985 locating non-absolute shared library symbol files.
2987 * Live range splitting
2989 GDB can now effectively debug code for which GCC has performed live
2990 range splitting as part of its optimization. See gdb/doc/LRS for
2991 more details on the expected format of the stabs information.
2995 GDB's support for the GNU Hurd, including thread debugging, has been
2996 updated to work with current versions of the Hurd.
3000 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3001 instruction set. ARM GDB automatically detects when Thumb
3002 instructions are in use, and adjusts disassembly and backtracing
3007 GDB's MIPS target configurations now handle the MIP16 16-bit
3012 GDB now includes support for overlays; if an executable has been
3013 linked such that multiple sections are based at the same address, GDB
3014 will decide which section to use for symbolic info. You can choose to
3015 control the decision manually, using overlay commands, or implement
3016 additional target-side support and use "overlay load-target" to bring
3017 in the overlay mapping. Do "help overlay" for more detail.
3021 The command "info symbol <address>" displays information about
3022 the symbol at the specified address.
3026 The standard remote protocol now includes an extension that allows
3027 asynchronous collection and display of trace data. This requires
3028 extensive support in the target-side debugging stub. Tracing mode
3029 includes a new interaction mode in GDB and new commands: see the
3030 file tracepoint.c for more details.
3034 Configurations for embedded MIPS now include a simulator contributed
3035 by Cygnus Solutions. The simulator supports the instruction sets
3036 of most MIPS variants.
3040 Sparc configurations may now include the ERC32 simulator contributed
3041 by the European Space Agency. The simulator is not built into
3042 Sparc targets by default; configure with --enable-sim to include it.
3046 For target configurations that may include multiple variants of a
3047 basic architecture (such as MIPS and SH), you may now set the
3048 architecture explicitly. "set arch" sets, "info arch" lists
3049 the possible architectures.
3051 *** Changes in GDB-4.16:
3053 * New native configurations
3055 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3056 M68K NetBSD m68k-*-netbsd*
3057 PowerPC AIX 4.x powerpc-*-aix*
3058 PowerPC MacOS powerpc-*-macos*
3059 PowerPC Windows NT powerpcle-*-cygwin32
3060 RS/6000 AIX 4.x rs6000-*-aix4*
3064 ARM with RDP protocol arm-*-*
3065 I960 with MON960 i960-*-coff
3066 MIPS VxWorks mips*-*-vxworks*
3067 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3068 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3070 Matra Sparclet sparclet-*-*
3074 The powerpc-eabi configuration now includes the PSIM simulator,
3075 contributed by Andrew Cagney, with assistance from Mike Meissner.
3076 PSIM is a very elaborate model of the PowerPC, including not only
3077 basic instruction set execution, but also details of execution unit
3078 performance and I/O hardware. See sim/ppc/README for more details.
3082 GDB now works with Solaris 2.5.
3084 * Windows 95/NT native
3086 GDB will now work as a native debugger on Windows 95 and Windows NT.
3087 To build it from source, you must use the "gnu-win32" environment,
3088 which uses a DLL to emulate enough of Unix to run the GNU tools.
3089 Further information, binaries, and sources are available at
3090 ftp.cygnus.com, under pub/gnu-win32.
3092 * dont-repeat command
3094 If a user-defined command includes the command `dont-repeat', then the
3095 command will not be repeated if the user just types return. This is
3096 useful if the command is time-consuming to run, so that accidental
3097 extra keystrokes don't run the same command many times.
3099 * Send break instead of ^C
3101 The standard remote protocol now includes an option to send a break
3102 rather than a ^C to the target in order to interrupt it. By default,
3103 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3105 * Remote protocol timeout
3107 The standard remote protocol includes a new variable `remotetimeout'
3108 that allows you to set the number of seconds before GDB gives up trying
3109 to read from the target. The default value is 2.
3111 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3113 By default GDB will automatically keep track of objects as they are
3114 loaded and unloaded by the dynamic linker. By using the command `set
3115 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3116 when shared library events occur, thus allowing you to set breakpoints
3117 in shared libraries which are explicitly loaded by the inferior.
3119 Note this feature does not work on hpux8. On hpux9 you must link
3120 /usr/lib/end.o into your program. This feature should work
3121 automatically on hpux10.
3123 * Irix 5.x hardware watchpoint support
3125 Irix 5 configurations now support the use of hardware watchpoints.
3127 * Mips protocol "SYN garbage limit"
3129 When debugging a Mips target using the `target mips' protocol, you
3130 may set the number of characters that GDB will ignore by setting
3131 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3132 every character. The default value is 1050.
3134 * Recording and replaying remote debug sessions
3136 If you set `remotelogfile' to the name of a file, gdb will write to it
3137 a recording of a remote debug session. This recording may then be
3138 replayed back to gdb using "gdbreplay". See gdbserver/README for
3139 details. This is useful when you have a problem with GDB while doing
3140 remote debugging; you can make a recording of the session and send it
3141 to someone else, who can then recreate the problem.
3143 * Speedups for remote debugging
3145 GDB includes speedups for downloading and stepping MIPS systems using
3146 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3147 and more efficient S-record downloading.
3149 * Memory use reductions and statistics collection
3151 GDB now uses less memory and reports statistics about memory usage.
3152 Try the `maint print statistics' command, for example.
3154 *** Changes in GDB-4.15:
3156 * Psymtabs for XCOFF
3158 The symbol reader for AIX GDB now uses partial symbol tables. This
3159 can greatly improve startup time, especially for large executables.
3161 * Remote targets use caching
3163 Remote targets now use a data cache to speed up communication with the
3164 remote side. The data cache could lead to incorrect results because
3165 it doesn't know about volatile variables, thus making it impossible to
3166 debug targets which use memory mapped I/O devices. `set remotecache
3167 off' turns the the data cache off.
3169 * Remote targets may have threads
3171 The standard remote protocol now includes support for multiple threads
3172 in the target system, using new protocol commands 'H' and 'T'. See
3173 gdb/remote.c for details.
3177 If GDB is configured with `--enable-netrom', then it will include
3178 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3179 acts as though it is a bank of ROM on the target board, but you can
3180 write into it over the network. GDB's support consists only of
3181 support for fast loading into the emulated ROM; to debug, you must use
3182 another protocol, such as standard remote protocol. The usual
3183 sequence is something like
3185 target nrom <netrom-hostname>
3187 target remote <netrom-hostname>:1235
3191 GDB now includes support for the Apple Macintosh, as a host only. It
3192 may be run as either an MPW tool or as a standalone application, and
3193 it can debug through the serial port. All the usual GDB commands are
3194 available, but to the target command, you must supply "serial" as the
3195 device type instead of "/dev/ttyXX". See mpw-README in the main
3196 directory for more information on how to build. The MPW configuration
3197 scripts */mpw-config.in support only a few targets, and only the
3198 mips-idt-ecoff target has been tested.
3202 GDB configuration now uses autoconf. This is not user-visible,
3203 but does simplify configuration and building.
3207 GDB now supports hpux10.
3209 *** Changes in GDB-4.14:
3211 * New native configurations
3213 x86 FreeBSD i[345]86-*-freebsd
3214 x86 NetBSD i[345]86-*-netbsd
3215 NS32k NetBSD ns32k-*-netbsd
3216 Sparc NetBSD sparc-*-netbsd
3220 A29K VxWorks a29k-*-vxworks
3221 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3222 CPU32 EST-300 emulator m68*-*-est*
3223 PowerPC ELF powerpc-*-elf
3226 * Alpha OSF/1 support for procfs
3228 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3229 possible to attach to running processes. As the mounting of the /proc
3230 filesystem is optional on the Alpha, GDB automatically determines
3231 the availability of /proc during startup. This can lead to problems
3232 if /proc is unmounted after GDB has been started.
3234 * Arguments to user-defined commands
3236 User commands may accept up to 10 arguments separated by whitespace.
3237 Arguments are accessed within the user command via $arg0..$arg9. A
3240 print $arg0 + $arg1 + $arg2
3242 To execute the command use:
3245 Defines the command "adder" which prints the sum of its three arguments.
3246 Note the arguments are text substitutions, so they may reference variables,
3247 use complex expressions, or even perform inferior function calls.
3249 * New `if' and `while' commands
3251 This makes it possible to write more sophisticated user-defined
3252 commands. Both commands take a single argument, which is the
3253 expression to evaluate, and must be followed by the commands to
3254 execute, one per line, if the expression is nonzero, the list being
3255 terminated by the word `end'. The `if' command list may include an
3256 `else' word, which causes the following commands to be executed only
3257 if the expression is zero.
3259 * Fortran source language mode
3261 GDB now includes partial support for Fortran 77. It will recognize
3262 Fortran programs and can evaluate a subset of Fortran expressions, but
3263 variables and functions may not be handled correctly. GDB will work
3264 with G77, but does not yet know much about symbols emitted by other
3267 * Better HPUX support
3269 Most debugging facilities now work on dynamic executables for HPPAs
3270 running hpux9 or later. You can attach to running dynamically linked
3271 processes, but by default the dynamic libraries will be read-only, so
3272 for instance you won't be able to put breakpoints in them. To change
3273 that behavior do the following before running the program:
3279 This will cause the libraries to be mapped private and read-write.
3280 To revert to the normal behavior, do this:
3286 You cannot set breakpoints or examine data in the library until after
3287 the library is loaded if the function/data symbols do not have
3290 GDB can now also read debug symbols produced by the HP C compiler on
3291 HPPAs (sorry, no C++, Fortran or 68k support).
3293 * Target byte order now dynamically selectable
3295 You can choose which byte order to use with a target system, via the
3296 commands "set endian big" and "set endian little", and you can see the
3297 current setting by using "show endian". You can also give the command
3298 "set endian auto", in which case GDB will use the byte order
3299 associated with the executable. Currently, only embedded MIPS
3300 configurations support dynamic selection of target byte order.
3302 * New DOS host serial code
3304 This version uses DPMI interrupts to handle buffered I/O, so you
3305 no longer need to run asynctsr when debugging boards connected to
3308 *** Changes in GDB-4.13:
3310 * New "complete" command
3312 This lists all the possible completions for the rest of the line, if it
3313 were to be given as a command itself. This is intended for use by emacs.
3315 * Trailing space optional in prompt
3317 "set prompt" no longer adds a space for you after the prompt you set. This
3318 allows you to set a prompt which ends in a space or one that does not.
3320 * Breakpoint hit counts
3322 "info break" now displays a count of the number of times the breakpoint
3323 has been hit. This is especially useful in conjunction with "ignore"; you
3324 can ignore a large number of breakpoint hits, look at the breakpoint info
3325 to see how many times the breakpoint was hit, then run again, ignoring one
3326 less than that number, and this will get you quickly to the last hit of
3329 * Ability to stop printing at NULL character
3331 "set print null-stop" will cause GDB to stop printing the characters of
3332 an array when the first NULL is encountered. This is useful when large
3333 arrays actually contain only short strings.
3335 * Shared library breakpoints
3337 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3338 breakpoints in shared libraries before the executable is run.
3340 * Hardware watchpoints
3342 There is a new hardware breakpoint for the watch command for sparclite
3343 targets. See gdb/sparclite/hw_breakpoint.note.
3345 Hardware watchpoints are also now supported under GNU/Linux.
3349 Annotations have been added. These are for use with graphical interfaces,
3350 and are still experimental. Currently only gdba.el uses these.
3352 * Improved Irix 5 support
3354 GDB now works properly with Irix 5.2.
3356 * Improved HPPA support
3358 GDB now works properly with the latest GCC and GAS.
3360 * New native configurations
3362 Sequent PTX4 i[34]86-sequent-ptx4
3363 HPPA running OSF/1 hppa*-*-osf*
3364 Atari TT running SVR4 m68*-*-sysv4*
3365 RS/6000 LynxOS rs6000-*-lynxos*
3369 OS/9000 i[34]86-*-os9k
3370 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3373 * Hitachi SH7000 and E7000-PC ICE support
3375 There is now support for communicating with the Hitachi E7000-PC ICE.
3376 This is available automatically when GDB is configured for the SH.
3380 As usual, a variety of small fixes and improvements, both generic
3381 and configuration-specific. See the ChangeLog for more detail.
3383 *** Changes in GDB-4.12:
3385 * Irix 5 is now supported
3389 GDB-4.12 on the HPPA has a number of changes which make it unable
3390 to debug the output from the currently released versions of GCC and
3391 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3392 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3393 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3396 *** Changes in GDB-4.11:
3398 * User visible changes:
3402 The "set remotedebug" option is now consistent between the mips remote
3403 target, remote targets using the gdb-specific protocol, UDI (AMD's
3404 debug protocol for the 29k) and the 88k bug monitor. It is now an
3405 integer specifying a debug level (normally 0 or 1, but 2 means more
3406 debugging info for the mips target).
3408 * DEC Alpha native support
3410 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3411 debug info, but GDB works fairly well with the DEC compiler and should
3412 work with a future GCC release. See the README file for a few
3413 Alpha-specific notes.
3415 * Preliminary thread implementation
3417 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3419 * LynxOS native and target support for 386
3421 This release has been hosted on LynxOS 2.2, and also can be configured
3422 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3425 * Improvements in C++ mangling/demangling.
3427 This release has much better g++ debugging, specifically in name
3428 mangling/demangling, virtual function calls, print virtual table,
3429 call methods, ...etc.
3431 *** Changes in GDB-4.10:
3433 * User visible changes:
3435 Remote debugging using the GDB-specific (`target remote') protocol now
3436 supports the `load' command. This is only useful if you have some
3437 other way of getting the stub to the target system, and you can put it
3438 somewhere in memory where it won't get clobbered by the download.
3440 Filename completion now works.
3442 When run under emacs mode, the "info line" command now causes the
3443 arrow to point to the line specified. Also, "info line" prints
3444 addresses in symbolic form (as well as hex).
3446 All vxworks based targets now support a user settable option, called
3447 vxworks-timeout. This option represents the number of seconds gdb
3448 should wait for responses to rpc's. You might want to use this if
3449 your vxworks target is, perhaps, a slow software simulator or happens
3450 to be on the far side of a thin network line.
3454 This release contains support for using a DEC alpha as a GDB host for
3455 cross debugging. Native alpha debugging is not supported yet.
3458 *** Changes in GDB-4.9:
3462 This is the first GDB release which is accompanied by a matching testsuite.
3463 The testsuite requires installation of dejagnu, which should be available
3464 via ftp from most sites that carry GNU software.
3468 'Cfront' style demangling has had its name changed to 'ARM' style, to
3469 emphasize that it was written from the specifications in the C++ Annotated
3470 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3471 disclaimers, it still generated too much confusion with users attempting to
3472 use gdb with AT&T cfront.
3476 GDB now uses a standard remote interface to a simulator library.
3477 So far, the library contains simulators for the Zilog Z8001/2, the
3478 Hitachi H8/300, H8/500 and Super-H.
3480 * New targets supported
3482 H8/300 simulator h8300-hitachi-hms or h8300hms
3483 H8/500 simulator h8500-hitachi-hms or h8500hms
3484 SH simulator sh-hitachi-hms or sh
3485 Z8000 simulator z8k-zilog-none or z8ksim
3486 IDT MIPS board over serial line mips-idt-ecoff
3488 Cross-debugging to GO32 targets is supported. It requires a custom
3489 version of the i386-stub.c module which is integrated with the
3490 GO32 memory extender.
3492 * New remote protocols
3494 MIPS remote debugging protocol.
3496 * New source languages supported
3498 This version includes preliminary support for Chill, a Pascal like language
3499 used by telecommunications companies. Chill support is also being integrated
3500 into the GNU compiler, but we don't know when it will be publically available.
3503 *** Changes in GDB-4.8:
3505 * HP Precision Architecture supported
3507 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3508 version of this support was available as a set of patches from the
3509 University of Utah. GDB does not support debugging of programs
3510 compiled with the HP compiler, because HP will not document their file
3511 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3512 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3514 Many problems in the preliminary version have been fixed.
3516 * Faster and better demangling
3518 We have improved template demangling and fixed numerous bugs in the GNU style
3519 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3520 character types (wchar_t) are now supported. Demangling of each symbol is now
3521 only done once, and is cached when the symbol table for a file is read in.
3522 This results in a small increase in memory usage for C programs, a moderate
3523 increase in memory usage for C++ programs, and a fantastic speedup in
3526 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3527 from the specifications in the Annotated Reference Manual, which AT&T's
3528 compiler does not actually implement.
3530 * G++ multiple inheritance compiler problem
3532 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3533 inheritance lattices was reworked to properly discover ambiguities. We
3534 recently found an example which causes this new algorithm to fail in a
3535 very subtle way, producing bad debug information for those classes.
3536 The file 'gcc.patch' (in this directory) can be applied to gcc to
3537 circumvent the problem. A future GCC release will contain a complete
3540 The previous G++ debug info problem (mentioned below for the gdb-4.7
3541 release) is fixed in gcc version 2.3.2.
3543 * Improved configure script
3545 The `configure' script will now attempt to guess your system type if
3546 you don't supply a host system type. The old scheme of supplying a
3547 host system triplet is preferable over using this. All the magic is
3548 done in the new `config.guess' script. Examine it for details.
3550 We have also brought our configure script much more in line with the FSF's
3551 version. It now supports the --with-xxx options. In particular,
3552 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3553 The resulting GDB will not be able to read arbitrary object file formats --
3554 only the format ``expected'' to be used on the configured target system.
3555 We hope to make this the default in a future release.
3557 * Documentation improvements
3559 There's new internal documentation on how to modify GDB, and how to
3560 produce clean changes to the code. We implore people to read it
3561 before submitting changes.
3563 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3564 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3565 `info' files are also provided. To build `info' files from scratch,
3566 you will need the latest `makeinfo' release, which will be available in
3567 a future texinfo-X.Y release.
3569 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3570 We're not sure exactly which versions have this problem, but it has
3571 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3572 or better. If that isn't possible, there is a patch in
3573 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3574 around this problem.
3578 GDB now supports array constants that can be used in expressions typed in by
3579 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3580 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3583 The new directory `gdb/sparclite' contains a program that demonstrates
3584 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3586 * New native hosts supported
3588 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3589 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3591 * New targets supported
3593 AMD 29k family via UDI a29k-amd-udi or udi29k
3595 * New file formats supported
3597 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3598 HPUX core files, and SCO 3.2v2 core files.
3602 Attaching to processes now works again; thanks for the many bug reports.
3604 We have also stomped on a bunch of core dumps caused by
3605 printf_filtered("%s") problems.
3607 We eliminated a copyright problem on the rpc and ptrace header files
3608 for VxWorks, which was discovered at the last minute during the 4.7
3609 release. You should now be able to build a VxWorks GDB.
3611 You can now interrupt gdb while an attached process is running. This
3612 will cause the attached process to stop, and give control back to GDB.
3614 We fixed problems caused by using too many file descriptors
3615 for reading symbols from object files and libraries. This was
3616 especially a problem for programs that used many (~100) shared
3619 The `step' command now only enters a subroutine if there is line number
3620 information for the subroutine. Otherwise it acts like the `next'
3621 command. Previously, `step' would enter subroutines if there was
3622 any debugging information about the routine. This avoids problems
3623 when using `cc -g1' on MIPS machines.
3625 * Internal improvements
3627 GDB's internal interfaces have been improved to make it easier to support
3628 debugging of multiple languages in the future.
3630 GDB now uses a common structure for symbol information internally.
3631 Minimal symbols (derived from linkage symbols in object files), partial
3632 symbols (from a quick scan of debug information), and full symbols
3633 contain a common subset of information, making it easier to write
3634 shared code that handles any of them.
3636 * New command line options
3638 We now accept --silent as an alias for --quiet.
3642 The memory-mapped-malloc library is now licensed under the GNU Library
3643 General Public License.
3645 *** Changes in GDB-4.7:
3647 * Host/native/target split
3649 GDB has had some major internal surgery to untangle the support for
3650 hosts and remote targets. Now, when you configure GDB for a remote
3651 target, it will no longer load in all of the support for debugging
3652 local programs on the host. When fully completed and tested, this will
3653 ensure that arbitrary host/target combinations are possible.
3655 The primary conceptual shift is to separate the non-portable code in
3656 GDB into three categories. Host specific code is required any time GDB
3657 is compiled on that host, regardless of the target. Target specific
3658 code relates to the peculiarities of the target, but can be compiled on
3659 any host. Native specific code is everything else: it can only be
3660 built when the host and target are the same system. Child process
3661 handling and core file support are two common `native' examples.
3663 GDB's use of /proc for controlling Unix child processes is now cleaner.
3664 It has been split out into a single module under the `target_ops' vector,
3665 plus two native-dependent functions for each system that uses /proc.
3667 * New hosts supported
3669 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3670 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3671 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3673 * New targets supported
3675 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3676 68030 and CPU32 m68030-*-*, m68332-*-*
3678 * New native hosts supported
3680 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3681 (386bsd is not well tested yet)
3682 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3684 * New file formats supported
3686 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3687 supports reading of `a.out.adobe' object files, which are an a.out
3688 format extended with minimal information about multiple sections.
3692 `show copying' is the same as the old `info copying'.
3693 `show warranty' is the same as `info warrantee'.
3694 These were renamed for consistency. The old commands continue to work.
3696 `info handle' is a new alias for `info signals'.
3698 You can now define pre-command hooks, which attach arbitrary command
3699 scripts to any command. The commands in the hook will be executed
3700 prior to the user's command. You can also create a hook which will be
3701 executed whenever the program stops. See gdb.texinfo.
3705 We now deal with Cfront style name mangling, and can even extract type
3706 info from mangled symbols. GDB can automatically figure out which
3707 symbol mangling style your C++ compiler uses.
3709 Calling of methods and virtual functions has been improved as well.
3713 The crash that occured when debugging Sun Ansi-C compiled binaries is
3714 fixed. This was due to mishandling of the extra N_SO stabs output
3717 We also finally got Ultrix 4.2 running in house, and fixed core file
3718 support, with help from a dozen people on the net.
3720 John M. Farrell discovered that the reason that single-stepping was so
3721 slow on all of the Mips based platforms (primarily SGI and DEC) was
3722 that we were trying to demangle and lookup a symbol used for internal
3723 purposes on every instruction that was being stepped through. Changing
3724 the name of that symbol so that it couldn't be mistaken for a C++
3725 mangled symbol sped things up a great deal.
3727 Rich Pixley sped up symbol lookups in general by getting much smarter
3728 about when C++ symbol mangling is necessary. This should make symbol
3729 completion (TAB on the command line) much faster. It's not as fast as
3730 we'd like, but it's significantly faster than gdb-4.6.
3734 A new user controllable variable 'call_scratch_address' can
3735 specify the location of a scratch area to be used when GDB
3736 calls a function in the target. This is necessary because the
3737 usual method of putting the scratch area on the stack does not work
3738 in systems that have separate instruction and data spaces.
3740 We integrated changes to support the 29k UDI (Universal Debugger
3741 Interface), but discovered at the last minute that we didn't have all
3742 of the appropriate copyright paperwork. We are working with AMD to
3743 resolve this, and hope to have it available soon.
3747 We have sped up the remote serial line protocol, especially for targets
3748 with lots of registers. It now supports a new `expedited status' ('T')
3749 message which can be used in place of the existing 'S' status message.
3750 This allows the remote stub to send only the registers that GDB
3751 needs to make a quick decision about single-stepping or conditional
3752 breakpoints, eliminating the need to fetch the entire register set for
3753 each instruction being stepped through.
3755 The GDB remote serial protocol now implements a write-through cache for
3756 registers, only re-reading the registers if the target has run.
3758 There is also a new remote serial stub for SPARC processors. You can
3759 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3760 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3761 processor with a serial port.
3765 Configure.in files have become much easier to read and modify. A new
3766 `table driven' format makes it more obvious what configurations are
3767 supported, and what files each one uses.
3771 There is a new opcodes library which will eventually contain all of the
3772 disassembly routines and opcode tables. At present, it only contains
3773 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3774 disassembler (binutils/objdump) to share these routines.
3776 The libiberty library is now copylefted under the GNU Library General
3777 Public License. This allows more liberal use, and was done so libg++
3778 can use it. This makes no difference to GDB, since the Library License
3779 grants all the rights from the General Public License.
3783 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3784 reference to the stabs symbol info used by the debugger. It is (as far
3785 as we know) the only published document on this fascinating topic. We
3786 encourage you to read it, compare it to the stabs information on your
3787 system, and send improvements on the document in general (to
3788 bug-gdb@prep.ai.mit.edu).
3790 And, of course, many bugs have been fixed.
3793 *** Changes in GDB-4.6:
3795 * Better support for C++ function names
3797 GDB now accepts as input the "demangled form" of C++ overloaded function
3798 names and member function names, and can do command completion on such names
3799 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3800 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3801 Make use of command completion, it is your friend.
3803 GDB also now accepts a variety of C++ mangled symbol formats. They are
3804 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3805 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3806 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3807 for the list of formats.
3809 * G++ symbol mangling problem
3811 Recent versions of gcc have a bug in how they emit debugging information for
3812 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3813 directory) can be applied to gcc to fix the problem. Alternatively, if you
3814 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3815 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3816 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3819 * New 'maintenance' command
3821 All of the commands related to hacking GDB internals have been moved out of
3822 the main command set, and now live behind the 'maintenance' command. This
3823 can also be abbreviated as 'mt'. The following changes were made:
3825 dump-me -> maintenance dump-me
3826 info all-breakpoints -> maintenance info breakpoints
3827 printmsyms -> maintenance print msyms
3828 printobjfiles -> maintenance print objfiles
3829 printpsyms -> maintenance print psymbols
3830 printsyms -> maintenance print symbols
3832 The following commands are new:
3834 maintenance demangle Call internal GDB demangler routine to
3835 demangle a C++ link name and prints the result.
3836 maintenance print type Print a type chain for a given symbol
3838 * Change to .gdbinit file processing
3840 We now read the $HOME/.gdbinit file before processing the argv arguments
3841 (e.g. reading symbol files or core files). This allows global parameters to
3842 be set, which will apply during the symbol reading. The ./.gdbinit is still
3843 read after argv processing.
3845 * New hosts supported
3847 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3849 GNU/Linux support i386-unknown-linux or linux
3851 We are also including code to support the HP/PA running BSD and HPUX. This
3852 is almost guaranteed not to work, as we didn't have time to test or build it
3853 for this release. We are including it so that the more adventurous (or
3854 masochistic) of you can play with it. We also had major problems with the
3855 fact that the compiler that we got from HP doesn't support the -g option.
3858 * New targets supported
3860 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3862 * More smarts about finding #include files
3864 GDB now remembers the compilation directory for all include files, and for
3865 all files from which C is generated (like yacc and lex sources). This
3866 greatly improves GDB's ability to find yacc/lex sources, and include files,
3867 especially if you are debugging your program from a directory different from
3868 the one that contains your sources.
3870 We also fixed a bug which caused difficulty with listing and setting
3871 breakpoints in include files which contain C code. (In the past, you had to
3872 try twice in order to list an include file that you hadn't looked at before.)
3874 * Interesting infernals change
3876 GDB now deals with arbitrary numbers of sections, where the symbols for each
3877 section must be relocated relative to that section's landing place in the
3878 target's address space. This work was needed to support ELF with embedded
3879 stabs used by Solaris-2.0.
3881 * Bug fixes (of course!)
3883 There have been loads of fixes for the following things:
3884 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3885 i960, stabs, DOS(GO32), procfs, etc...
3887 See the ChangeLog for details.
3889 *** Changes in GDB-4.5:
3891 * New machines supported (host and target)
3893 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3895 SGI Irix-4.x mips-sgi-irix4 or iris4
3897 * New malloc package
3899 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3900 Mmalloc is capable of handling mutiple heaps of memory. It is also
3901 capable of saving a heap to a file, and then mapping it back in later.
3902 This can be used to greatly speedup the startup of GDB by using a
3903 pre-parsed symbol table which lives in a mmalloc managed heap. For
3904 more details, please read mmalloc/mmalloc.texi.
3908 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3909 'help info proc' for details.
3911 * MIPS ecoff symbol table format
3913 The code that reads MIPS symbol table format is now supported on all hosts.
3914 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3917 * File name changes for MS-DOS
3919 Many files in the config directories have been renamed to make it easier to
3920 support GDB on MS-DOSe systems (which have very restrictive file name
3921 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3922 environment) is close to working but has some remaining problems. Note
3923 that debugging of DOS programs is not supported, due to limitations
3924 in the ``operating system'', but it can be used to host cross-debugging.
3926 * Cross byte order fixes
3928 Many fixes have been made to support cross debugging of Sparc and MIPS
3929 targets from hosts whose byte order differs.
3931 * New -mapped and -readnow options
3933 If memory-mapped files are available on your system through the 'mmap'
3934 system call, you can use the -mapped option on the `file' or
3935 `symbol-file' commands to cause GDB to write the symbols from your
3936 program into a reusable file. If the program you are debugging is
3937 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3938 Future GDB debugging sessions will notice the presence of this file,
3939 and will quickly map in symbol information from it, rather than reading
3940 the symbol table from the executable program. Using the '-mapped'
3941 option in a GDB `file' or `symbol-file' command has the same effect as
3942 starting GDB with the '-mapped' command-line option.
3944 You can cause GDB to read the entire symbol table immediately by using
3945 the '-readnow' option with any of the commands that load symbol table
3946 information (or on the GDB command line). This makes the command
3947 slower, but makes future operations faster.
3949 The -mapped and -readnow options are typically combined in order to
3950 build a `fred.syms' file that contains complete symbol information.
3951 A simple GDB invocation to do nothing but build a `.syms' file for future
3954 gdb -batch -nx -mapped -readnow programname
3956 The `.syms' file is specific to the host machine on which GDB is run.
3957 It holds an exact image of GDB's internal symbol table. It cannot be
3958 shared across multiple host platforms.
3960 * longjmp() handling
3962 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3963 siglongjmp() without losing control. This feature has not yet been ported to
3964 all systems. It currently works on many 386 platforms, all MIPS-based
3965 platforms (SGI, DECstation, etc), and Sun3/4.
3969 Preliminary work has been put in to support the new Solaris OS from Sun. At
3970 this time, it can control and debug processes, but it is not capable of
3975 As always, many many bug fixes. The major areas were with g++, and mipsread.
3976 People using the MIPS-based platforms should experience fewer mysterious
3977 crashes and trashed symbol tables.
3979 *** Changes in GDB-4.4:
3981 * New machines supported (host and target)
3983 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3985 BSD Reno on Vax vax-dec-bsd
3986 Ultrix on Vax vax-dec-ultrix
3988 * New machines supported (target)
3990 AMD 29000 embedded, using EBMON a29k-none-none
3994 GDB continues to improve its handling of C++. `References' work better.
3995 The demangler has also been improved, and now deals with symbols mangled as
3996 per the Annotated C++ Reference Guide.
3998 GDB also now handles `stabs' symbol information embedded in MIPS
3999 `ecoff' symbol tables. Since the ecoff format was not easily
4000 extensible to handle new languages such as C++, this appeared to be a
4001 good way to put C++ debugging info into MIPS binaries. This option
4002 will be supported in the GNU C compiler, version 2, when it is
4005 * New features for SVR4
4007 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4008 shared libraries. Debugging dynamically linked programs should present
4009 only minor differences from debugging statically linked programs.
4011 The `info proc' command will print out information about any process
4012 on an SVR4 system (including the one you are debugging). At the moment,
4013 it prints the address mappings of the process.
4015 If you bring up GDB on another SVR4 system, please send mail to
4016 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4018 * Better dynamic linking support in SunOS
4020 Reading symbols from shared libraries which contain debugging symbols
4021 now works properly. However, there remain issues such as automatic
4022 skipping of `transfer vector' code during function calls, which
4023 make it harder to debug code in a shared library, than to debug the
4024 same code linked statically.
4028 GDB is now using the latest `getopt' routines from the FSF. This
4029 version accepts the -- prefix for options with long names. GDB will
4030 continue to accept the old forms (-option and +option) as well.
4031 Various single letter abbreviations for options have been explicity
4032 added to the option table so that they won't get overshadowed in the
4033 future by other options that begin with the same letter.
4037 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4038 Many assorted bugs have been handled. Many more remain to be handled.
4039 See the various ChangeLog files (primarily in gdb and bfd) for details.
4042 *** Changes in GDB-4.3:
4044 * New machines supported (host and target)
4046 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4047 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4048 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4050 * Almost SCO Unix support
4052 We had hoped to support:
4053 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4054 (except for core file support), but we discovered very late in the release
4055 that it has problems with process groups that render gdb unusable. Sorry
4056 about that. I encourage people to fix it and post the fixes.
4058 * Preliminary ELF and DWARF support
4060 GDB can read ELF object files on System V Release 4, and can handle
4061 debugging records for C, in DWARF format, in ELF files. This support
4062 is preliminary. If you bring up GDB on another SVR4 system, please
4063 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4068 GDB now uses the latest `readline' library. One user-visible change
4069 is that two tabs will list possible command completions, which previously
4070 required typing M-? (meta-question mark, or ESC ?).
4074 The `stepi' bug that many of you noticed has been squashed.
4075 Many bugs in C++ have been handled. Many more remain to be handled.
4076 See the various ChangeLog files (primarily in gdb and bfd) for details.
4078 * State of the MIPS world (in case you wondered):
4080 GDB can understand the symbol tables emitted by the compilers
4081 supplied by most vendors of MIPS-based machines, including DEC. These
4082 symbol tables are in a format that essentially nobody else uses.
4084 Some versions of gcc come with an assembler post-processor called
4085 mips-tfile. This program is required if you want to do source-level
4086 debugging of gcc-compiled programs. I believe FSF does not ship
4087 mips-tfile with gcc version 1, but it will eventually come with gcc
4090 Debugging of g++ output remains a problem. g++ version 1.xx does not
4091 really support it at all. (If you're lucky, you should be able to get
4092 line numbers and stack traces to work, but no parameters or local
4093 variables.) With some work it should be possible to improve the
4096 When gcc version 2 is released, you will have somewhat better luck.
4097 However, even then you will get confusing results for inheritance and
4100 We will eventually provide full debugging of g++ output on
4101 DECstations. This will probably involve some kind of stabs-in-ecoff
4102 encapulation, but the details have not been worked out yet.
4105 *** Changes in GDB-4.2:
4107 * Improved configuration
4109 Only one copy of `configure' exists now, and it is not self-modifying.
4110 Porting BFD is simpler.
4114 The `step' and `next' commands now only stop at the first instruction
4115 of a source line. This prevents the multiple stops that used to occur
4116 in switch statements, for-loops, etc. `Step' continues to stop if a
4117 function that has debugging information is called within the line.
4121 Lots of small bugs fixed. More remain.
4123 * New host supported (not target)
4125 Intel 386 PC clone running Mach i386-none-mach
4128 *** Changes in GDB-4.1:
4130 * Multiple source language support
4132 GDB now has internal scaffolding to handle several source languages.
4133 It determines the type of each source file from its filename extension,
4134 and will switch expression parsing and number formatting to match the
4135 language of the function in the currently selected stack frame.
4136 You can also specifically set the language to be used, with
4137 `set language c' or `set language modula-2'.
4141 GDB now has preliminary support for the GNU Modula-2 compiler,
4142 currently under development at the State University of New York at
4143 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4144 continue through the fall of 1991 and into 1992.
4146 Other Modula-2 compilers are currently not supported, and attempting to
4147 debug programs compiled with them will likely result in an error as the
4148 symbol table is read. Feel free to work on it, though!
4150 There are hooks in GDB for strict type checking and range checking,
4151 in the `Modula-2 philosophy', but they do not currently work.
4155 GDB can now write to executable and core files (e.g. patch
4156 a variable's value). You must turn this switch on, specify
4157 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4158 by assigning a new value to a variable. Modifications take
4161 * Automatic SunOS shared library reading
4163 When you run your program, GDB automatically determines where its
4164 shared libraries (if any) have been loaded, and reads their symbols.
4165 The `share' command is no longer needed. This also works when
4166 examining core files.
4170 You can specify the number of lines that the `list' command shows.
4173 * New machines supported (host and target)
4175 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4176 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4177 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4179 * New hosts supported (not targets)
4181 IBM RT/PC: romp-ibm-aix or rtpc
4183 * New targets supported (not hosts)
4185 AMD 29000 embedded with COFF a29k-none-coff
4186 AMD 29000 embedded with a.out a29k-none-aout
4187 Ultracomputer remote kernel debug a29k-nyu-kern
4189 * New remote interfaces
4195 *** Changes in GDB-4.0:
4199 Wide output is wrapped at good places to make the output more readable.
4201 Gdb now supports cross-debugging from a host machine of one type to a
4202 target machine of another type. Communication with the target system
4203 is over serial lines. The ``target'' command handles connecting to the
4204 remote system; the ``load'' command will download a program into the
4205 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4206 also supports debugging of realtime processes running under VxWorks,
4207 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4208 stub on the target system.
4210 New CPUs supported include the AMD 29000 and Intel 960.
4212 GDB now reads object files and symbol tables via a ``binary file''
4213 library, which allows a single copy of GDB to debug programs of multiple
4214 object file types such as a.out and coff.
4216 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4217 refcard.dvi and refcard.ps are available to format it).
4220 * Control-Variable user interface simplified
4222 All variables that control the operation of the debugger can be set
4223 by the ``set'' command, and displayed by the ``show'' command.
4225 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4226 ``Show prompt'' produces the response:
4227 Gdb's prompt is new-gdb=>.
4229 What follows are the NEW set commands. The command ``help set'' will
4230 print a complete list of old and new set commands. ``help set FOO''
4231 will give a longer description of the variable FOO. ``show'' will show
4232 all of the variable descriptions and their current settings.
4234 confirm on/off: Enables warning questions for operations that are
4235 hard to recover from, e.g. rerunning the program while
4236 it is already running. Default is ON.
4238 editing on/off: Enables EMACS style command line editing
4239 of input. Previous lines can be recalled with
4240 control-P, the current line can be edited with control-B,
4241 you can search for commands with control-R, etc.
4244 history filename NAME: NAME is where the gdb command history
4245 will be stored. The default is .gdb_history,
4246 or the value of the environment variable
4249 history size N: The size, in commands, of the command history. The
4250 default is 256, or the value of the environment variable
4253 history save on/off: If this value is set to ON, the history file will
4254 be saved after exiting gdb. If set to OFF, the
4255 file will not be saved. The default is OFF.
4257 history expansion on/off: If this value is set to ON, then csh-like
4258 history expansion will be performed on
4259 command line input. The default is OFF.
4261 radix N: Sets the default radix for input and output. It can be set
4262 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4263 in the current radix, so "set radix 10" is always a no-op.
4265 height N: This integer value is the number of lines on a page. Default
4266 is 24, the current `stty rows'' setting, or the ``li#''
4267 setting from the termcap entry matching the environment
4270 width N: This integer value is the number of characters on a line.
4271 Default is 80, the current `stty cols'' setting, or the ``co#''
4272 setting from the termcap entry matching the environment
4275 Note: ``set screensize'' is obsolete. Use ``set height'' and
4276 ``set width'' instead.
4278 print address on/off: Print memory addresses in various command displays,
4279 such as stack traces and structure values. Gdb looks
4280 more ``symbolic'' if you turn this off; it looks more
4281 ``machine level'' with it on. Default is ON.
4283 print array on/off: Prettyprint arrays. New convenient format! Default
4286 print demangle on/off: Print C++ symbols in "source" form if on,
4289 print asm-demangle on/off: Same, for assembler level printouts
4292 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4295 * Support for Epoch Environment.
4297 The epoch environment is a version of Emacs v18 with windowing. One
4298 new command, ``inspect'', is identical to ``print'', except that if you
4299 are running in the epoch environment, the value is printed in its own
4303 * Support for Shared Libraries
4305 GDB can now debug programs and core files that use SunOS shared libraries.
4306 Symbols from a shared library cannot be referenced
4307 before the shared library has been linked with the program (this
4308 happens after you type ``run'' and before the function main() is entered).
4309 At any time after this linking (including when examining core files
4310 from dynamically linked programs), gdb reads the symbols from each
4311 shared library when you type the ``sharedlibrary'' command.
4312 It can be abbreviated ``share''.
4314 sharedlibrary REGEXP: Load shared object library symbols for files
4315 matching a unix regular expression. No argument
4316 indicates to load symbols for all shared libraries.
4318 info sharedlibrary: Status of loaded shared libraries.
4323 A watchpoint stops execution of a program whenever the value of an
4324 expression changes. Checking for this slows down execution
4325 tremendously whenever you are in the scope of the expression, but is
4326 quite useful for catching tough ``bit-spreader'' or pointer misuse
4327 problems. Some machines such as the 386 have hardware for doing this
4328 more quickly, and future versions of gdb will use this hardware.
4330 watch EXP: Set a watchpoint (breakpoint) for an expression.
4332 info watchpoints: Information about your watchpoints.
4334 delete N: Deletes watchpoint number N (same as breakpoints).
4335 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4336 enable N: Re-enables watchpoint number N (same as breakpoints).
4339 * C++ multiple inheritance
4341 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4344 * C++ exception handling
4346 Gdb now supports limited C++ exception handling. Besides the existing
4347 ability to breakpoint on an exception handler, gdb can breakpoint on
4348 the raising of an exception (before the stack is peeled back to the
4351 catch FOO: If there is a FOO exception handler in the dynamic scope,
4352 set a breakpoint to catch exceptions which may be raised there.
4353 Multiple exceptions (``catch foo bar baz'') may be caught.
4355 info catch: Lists all exceptions which may be caught in the
4356 current stack frame.
4359 * Minor command changes
4361 The command ``call func (arg, arg, ...)'' now acts like the print
4362 command, except it does not print or save a value if the function's result
4363 is void. This is similar to dbx usage.
4365 The ``up'' and ``down'' commands now always print the frame they end up
4366 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4367 frames without printing.
4369 * New directory command
4371 'dir' now adds directories to the FRONT of the source search path.
4372 The path starts off empty. Source files that contain debug information
4373 about the directory in which they were compiled can be found even
4374 with an empty path; Sun CC and GCC include this information. If GDB can't
4375 find your source file in the current directory, type "dir .".
4377 * Configuring GDB for compilation
4379 For normal use, type ``./configure host''. See README or gdb.texinfo
4382 GDB now handles cross debugging. If you are remotely debugging between
4383 two different machines, type ``./configure host -target=targ''.
4384 Host is the machine where GDB will run; targ is the machine
4385 where the program that you are debugging will run.