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)
15 ** Module gdb.types has been added.
16 It contains a collection of utilities for working with gdb.Types objects:
17 get_basic_type, has_field, make_enum_dict.
21 ** GDB now puts template parameters in scope when debugging in an
22 instantiation. For example, if you have:
24 template<int X> int func (void) { return X; }
26 then if you step into func<5>, "print X" will show "5". This
27 feature requires proper debuginfo support from the compiler; it
30 * GDB now has some support for using labels in the program's source in
31 linespecs. For instance, you can use "advance label" to continue
34 * GDB now has support for reading and writing a new .gdb_index
35 section. This section holds a fast index of DWARF debugging
36 information and can be used to greatly speed up GDB startup and
37 operation. See the documentation for `save gdb-index' for details.
39 * The "watch" command now accepts an optional "-location" argument.
40 When used, this causes GDB to watch the memory referred to by the
41 expression. Such a watchpoint is never deleted due to it going out
44 * GDB now supports thread debugging of core dumps on GNU/Linux.
46 GDB now activates thread debugging using the libthread_db library
47 when debugging GNU/Linux core dumps, similarly to when debugging
48 live processes. As a result, when debugging a core dump file, GDB
49 is now able to display pthread_t ids of threads. For example, "info
50 threads" shows the same output as when debugging the process when it
51 was live. In earlier releases, you'd see something like this:
54 * 1 LWP 6780 main () at main.c:10
56 While now you see this:
59 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
61 It is also now possible to inspect TLS variables when debugging core
64 When debugging a core dump generated on a machine other than the one
65 used to run GDB, you may need to point GDB at the correct
66 libthread_db library with the "set libthread-db-search-path"
67 command. See the user manual for more details on this command.
69 * New features in the GDB remote stub, GDBserver
71 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
72 and i686 LynxOS (version 5.x).
74 * Ada task switching is now supported on sparc-elf targets when
75 debugging a program using the Ravenscar Profile. For more information,
76 see the "Tasking Support when using the Ravenscar Profile" section
77 in the GDB user manual.
79 * Guile support was removed.
81 *** Changes in GDB 7.2
83 * Shared library support for remote targets by default
85 When GDB is configured for a generic, non-OS specific target, like
86 for example, --target=arm-eabi or one of the many *-*-elf targets,
87 GDB now queries remote stubs for loaded shared libraries using the
88 `qXfer:libraries:read' packet. Previously, shared library support
89 was always disabled for such configurations.
93 ** Argument Dependent Lookup (ADL)
95 In C++ ADL lookup directs function search to the namespaces of its
96 arguments even if the namespace has not been imported.
106 Here the compiler will search for `foo' in the namespace of 'b'
107 and find A::foo. GDB now supports this. This construct is commonly
108 used in the Standard Template Library for operators.
110 ** Improved User Defined Operator Support
112 In addition to member operators, GDB now supports lookup of operators
113 defined in a namespace and imported with a `using' directive, operators
114 defined in the global scope, operators imported implicitly from an
115 anonymous namespace, and the ADL operators mentioned in the previous
117 GDB now also supports proper overload resolution for all the previously
118 mentioned flavors of operators.
120 ** static const class members
122 Printing of static const class members that are initialized in the
123 class definition has been fixed.
125 * Windows Thread Information Block access.
127 On Windows targets, GDB now supports displaying the Windows Thread
128 Information Block (TIB) structure. This structure is visible either
129 by using the new command `info w32 thread-information-block' or, by
130 dereferencing the new convenience variable named `$_tlb', a
131 thread-specific pointer to the TIB. This feature is also supported
132 when remote debugging using GDBserver.
136 Static tracepoints are calls in the user program into a tracing
137 library. One such library is a port of the LTTng kernel tracer to
138 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
139 When debugging with GDBserver, GDB now supports combining the GDB
140 tracepoint machinery with such libraries. For example: the user can
141 use GDB to probe a static tracepoint marker (a call from the user
142 program into the tracing library) with the new "strace" command (see
143 "New commands" below). This creates a "static tracepoint" in the
144 breakpoint list, that can be manipulated with the same feature set
145 as fast and regular tracepoints. E.g., collect registers, local and
146 global variables, collect trace state variables, and define
147 tracepoint conditions. In addition, the user can collect extra
148 static tracepoint marker specific data, by collecting the new
149 $_sdata internal variable. When analyzing the trace buffer, you can
150 inspect $_sdata like any other variable available to GDB. For more
151 information, see the "Tracepoints" chapter in GDB user manual. New
152 remote packets have been defined to support static tracepoints, see
153 the "New remote packets" section below.
155 * Better reconstruction of tracepoints after disconnected tracing
157 GDB will attempt to download the original source form of tracepoint
158 definitions when starting a trace run, and then will upload these
159 upon reconnection to the target, resulting in a more accurate
160 reconstruction of the tracepoints that are in use on the target.
164 You can now exercise direct control over the ways that GDB can
165 affect your program. For instance, you can disallow the setting of
166 breakpoints, so that the program can run continuously (assuming
167 non-stop mode). In addition, the "observer" variable is available
168 to switch all of the different controls; in observer mode, GDB
169 cannot affect the target's behavior at all, which is useful for
170 tasks like diagnosing live systems in the field.
172 * The new convenience variable $_thread holds the number of the
179 Return the address of the Windows Thread Information Block of a given thread.
183 In response to several of the tracepoint packets, the target may now
184 also respond with a number of intermediate `qRelocInsn' request
185 packets before the final result packet, to have GDB handle
186 relocating an instruction to execute at a different address. This
187 is particularly useful for stubs that support fast tracepoints. GDB
188 reports support for this feature in the qSupported packet.
192 List static tracepoint markers in the target program.
196 List static tracepoint markers at a given address in the target
199 qXfer:statictrace:read
201 Read the static trace data collected (by a `collect $_sdata'
202 tracepoint action). The remote stub reports support for this packet
203 to gdb's qSupported query.
207 Send the current settings of GDB's permission flags.
211 Send part of the source (textual) form of a tracepoint definition,
212 which includes location, conditional, and action list.
214 * The source command now accepts a -s option to force searching for the
215 script in the source search path even if the script name specifies
218 * New features in the GDB remote stub, GDBserver
220 - GDBserver now support tracepoints (including fast tracepoints, and
221 static tracepoints). The feature is currently supported by the
222 i386-linux and amd64-linux builds. See the "Tracepoints support
223 in gdbserver" section in the manual for more information.
225 GDBserver JIT compiles the tracepoint's conditional agent
226 expression bytecode into native code whenever possible for low
227 overhead dynamic tracepoints conditionals. For such tracepoints,
228 an expression that examines program state is evaluated when the
229 tracepoint is reached, in order to determine whether to capture
230 trace data. If the condition is simple and false, processing the
231 tracepoint finishes very quickly and no data is gathered.
233 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
234 for static tracepoints support.
236 - GDBserver now supports x86_64 Windows 64-bit debugging.
238 * GDB now sends xmlRegisters= in qSupported packet to indicate that
239 it understands register description.
241 * The --batch flag now disables pagination and queries.
243 * X86 general purpose registers
245 GDB now supports reading/writing byte, word and double-word x86
246 general purpose registers directly. This means you can use, say,
247 $ah or $ax to refer, respectively, to the byte register AH and
248 16-bit word register AX that are actually portions of the 32-bit
249 register EAX or 64-bit register RAX.
251 * The `commands' command now accepts a range of breakpoints to modify.
252 A plain `commands' following a command that creates multiple
253 breakpoints affects all the breakpoints set by that command. This
254 applies to breakpoints set by `rbreak', and also applies when a
255 single `break' command creates multiple breakpoints (e.g.,
256 breakpoints on overloaded c++ functions).
258 * The `rbreak' command now accepts a filename specification as part of
259 its argument, limiting the functions selected by the regex to those
260 in the specified file.
262 * Support for remote debugging Windows and SymbianOS shared libraries
263 from Unix hosts has been improved. Non Windows GDB builds now can
264 understand target reported file names that follow MS-DOS based file
265 system semantics, such as file names that include drive letters and
266 use the backslash character as directory separator. This makes it
267 possible to transparently use the "set sysroot" and "set
268 solib-search-path" on Unix hosts to point as host copies of the
269 target's shared libraries. See the new command "set
270 target-file-system-kind" described below, and the "Commands to
271 specify files" section in the user manual for more information.
275 eval template, expressions...
276 Convert the values of one or more expressions under the control
277 of the string template to a command line, and call it.
279 set target-file-system-kind unix|dos-based|auto
280 show target-file-system-kind
281 Set or show the assumed file system kind for target reported file
284 save breakpoints <filename>
285 Save all current breakpoint definitions to a file suitable for use
286 in a later debugging session. To read the saved breakpoint
287 definitions, use the `source' command.
289 `save tracepoints' is a new alias for `save-tracepoints'. The latter
292 info static-tracepoint-markers
293 Display information about static tracepoint markers in the target.
295 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
296 Define a static tracepoint by probing a marker at the given
297 function, line, address, or marker ID.
301 Enable and disable observer mode.
303 set may-write-registers on|off
304 set may-write-memory on|off
305 set may-insert-breakpoints on|off
306 set may-insert-tracepoints on|off
307 set may-insert-fast-tracepoints on|off
308 set may-interrupt on|off
309 Set individual permissions for GDB effects on the target. Note that
310 some of these settings can have undesirable or surprising
311 consequences, particularly when changed in the middle of a session.
312 For instance, disabling the writing of memory can prevent
313 breakpoints from being inserted, cause single-stepping to fail, or
314 even crash your program, if you disable after breakpoints have been
315 inserted. However, GDB should not crash.
317 set record memory-query on|off
318 show record memory-query
319 Control whether to stop the inferior if memory changes caused
320 by an instruction cannot be recorded.
325 The disassemble command now supports "start,+length" form of two arguments.
329 ** GDB now provides a new directory location, called the python directory,
330 where Python scripts written for GDB can be installed. The location
331 of that directory is <data-directory>/python, where <data-directory>
332 is the GDB data directory. For more details, see section `Scripting
333 GDB using Python' in the manual.
335 ** The GDB Python API now has access to breakpoints, symbols, symbol
336 tables, program spaces, inferiors, threads and frame's code blocks.
337 Additionally, GDB Parameters can now be created from the API, and
338 manipulated via set/show in the CLI.
340 ** New functions gdb.target_charset, gdb.target_wide_charset,
341 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
343 ** New exception gdb.GdbError.
345 ** Pretty-printers are now also looked up in the current program space.
347 ** Pretty-printers can now be individually enabled and disabled.
349 ** GDB now looks for names of Python scripts to auto-load in a
350 special section named `.debug_gdb_scripts', in addition to looking
351 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
353 * Tracepoint actions were unified with breakpoint commands. In particular,
354 there are no longer differences in "info break" output for breakpoints and
355 tracepoints and the "commands" command can be used for both tracepoints and
360 ARM Symbian arm*-*-symbianelf*
362 * D language support.
363 GDB now supports debugging programs written in the D programming
366 * GDB now supports the extended ptrace interface for PowerPC which is
367 available since Linux kernel version 2.6.34. This automatically enables
368 any hardware breakpoints and additional hardware watchpoints available in
369 the processor. The old ptrace interface exposes just one hardware
370 watchpoint and no hardware breakpoints.
372 * GDB is now able to use the Data Value Compare (DVC) register available on
373 embedded PowerPC processors to implement in hardware simple watchpoint
374 conditions of the form:
376 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
378 This works in native GDB running on Linux kernels with the extended ptrace
379 interface mentioned above.
381 *** Changes in GDB 7.1
387 GDB now supports importing of namespaces in C++. This enables the
388 user to inspect variables from imported namespaces. Support for
389 namepace aliasing has also been added. So, if a namespace is
390 aliased in the current scope (e.g. namepace C=A; ) the user can
391 print variables using the alias (e.g. (gdb) print C::x).
395 All known bugs relating to the printing of virtual base class were
396 fixed. It is now possible to call overloaded static methods using a
401 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
402 and reinterpret_cast<> are now handled by the C++ expression parser.
406 Xilinx MicroBlaze microblaze-*-*
411 Xilinx MicroBlaze microblaze
414 * Multi-program debugging.
416 GDB now has support for multi-program (a.k.a. multi-executable or
417 multi-exec) debugging. This allows for debugging multiple inferiors
418 simultaneously each running a different program under the same GDB
419 session. See "Debugging Multiple Inferiors and Programs" in the
420 manual for more information. This implied some user visible changes
421 in the multi-inferior support. For example, "info inferiors" now
422 lists inferiors that are not running yet or that have exited
423 already. See also "New commands" and "New options" below.
425 * New tracing features
427 GDB's tracepoint facility now includes several new features:
429 ** Trace state variables
431 GDB tracepoints now include support for trace state variables, which
432 are variables managed by the target agent during a tracing
433 experiment. They are useful for tracepoints that trigger each
434 other, so for instance one tracepoint can count hits in a variable,
435 and then a second tracepoint has a condition that is true when the
436 count reaches a particular value. Trace state variables share the
437 $-syntax of GDB convenience variables, and can appear in both
438 tracepoint actions and condition expressions. Use the "tvariable"
439 command to create, and "info tvariables" to view; see "Trace State
440 Variables" in the manual for more detail.
444 GDB now includes an option for defining fast tracepoints, which
445 targets may implement more efficiently, such as by installing a jump
446 into the target agent rather than a trap instruction. The resulting
447 speedup can be by two orders of magnitude or more, although the
448 tradeoff is that some program locations on some target architectures
449 might not allow fast tracepoint installation, for instance if the
450 instruction to be replaced is shorter than the jump. To request a
451 fast tracepoint, use the "ftrace" command, with syntax identical to
452 the regular trace command.
454 ** Disconnected tracing
456 It is now possible to detach GDB from the target while it is running
457 a trace experiment, then reconnect later to see how the experiment
458 is going. In addition, a new variable disconnected-tracing lets you
459 tell the target agent whether to continue running a trace if the
460 connection is lost unexpectedly.
464 GDB now has the ability to save the trace buffer into a file, and
465 then use that file as a target, similarly to you can do with
466 corefiles. You can select trace frames, print data that was
467 collected in them, and use tstatus to display the state of the
468 tracing run at the moment that it was saved. To create a trace
469 file, use "tsave <filename>", and to use it, do "target tfile
472 ** Circular trace buffer
474 You can ask the target agent to handle the trace buffer as a
475 circular buffer, discarding the oldest trace frames to make room for
476 newer ones, by setting circular-trace-buffer to on. This feature may
477 not be available for all target agents.
482 The disassemble command, when invoked with two arguments, now requires
483 the arguments to be comma-separated.
486 The info variables command now displays variable definitions. Files
487 which only declare a variable are not shown.
490 The source command is now capable of sourcing Python scripts.
491 This feature is dependent on the debugger being build with Python
494 Related to this enhancement is also the introduction of a new command
495 "set script-extension" (see below).
497 * New commands (for set/show, see "New options" below)
499 record save [<FILENAME>]
500 Save a file (in core file format) containing the process record
501 execution log for replay debugging at a later time.
503 record restore <FILENAME>
504 Restore the process record execution log that was saved at an
505 earlier time, for replay debugging.
507 add-inferior [-copies <N>] [-exec <FILENAME>]
510 clone-inferior [-copies <N>] [ID]
511 Make a new inferior ready to execute the same program another
517 maint info program-spaces
518 List the program spaces loaded into GDB.
520 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
521 show remote interrupt-sequence
522 Allow the user to select one of ^C, a BREAK signal or BREAK-g
523 as the sequence to the remote target in order to interrupt the execution.
524 Ctrl-C is a default. Some system prefers BREAK which is high level of
525 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
526 Magic SysRq g. It is BREAK signal and character 'g'.
528 set remote interrupt-on-connect [on | off]
529 show remote interrupt-on-connect
530 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
531 remote target when gdb connects to it. This is needed when you debug
534 set remotebreak [on | off]
536 Deprecated. Use "set/show remote interrupt-sequence" instead.
538 tvariable $NAME [ = EXP ]
539 Create or modify a trace state variable.
542 List trace state variables and their values.
544 delete tvariable $NAME ...
545 Delete one or more trace state variables.
548 Evaluate the given expressions without collecting anything into the
549 trace buffer. (Valid in tracepoint actions only.)
551 ftrace FN / FILE:LINE / *ADDR
552 Define a fast tracepoint at the given function, line, or address.
554 * New expression syntax
556 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
557 GDB now parses 0b101010 identically with 42.
561 set follow-exec-mode new|same
562 show follow-exec-mode
563 Control whether GDB reuses the same inferior across an exec call or
564 creates a new one. This is useful to be able to restart the old
565 executable after the inferior having done an exec call.
567 set default-collect EXPR, ...
569 Define a list of expressions to be collected at each tracepoint.
570 This is a useful way to ensure essential items are not overlooked,
571 such as registers or a critical global variable.
573 set disconnected-tracing
574 show disconnected-tracing
575 If set to 1, the target is instructed to continue tracing if it
576 loses its connection to GDB. If 0, the target is to stop tracing
579 set circular-trace-buffer
580 show circular-trace-buffer
581 If set to on, the target is instructed to use a circular trace buffer
582 and discard the oldest trace frames instead of stopping the trace due
583 to a full trace buffer. If set to off, the trace stops when the buffer
584 fills up. Some targets may not support this.
586 set script-extension off|soft|strict
587 show script-extension
588 If set to "off", the debugger does not perform any script language
589 recognition, and all sourced files are assumed to be GDB scripts.
590 If set to "soft" (the default), files are sourced according to
591 filename extension, falling back to GDB scripts if the first
593 If set to "strict", files are sourced according to filename extension.
595 set ada trust-PAD-over-XVS on|off
596 show ada trust-PAD-over-XVS
597 If off, activate a workaround against a bug in the debugging information
598 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
599 the GCC sources for more information about the GNAT encoding and
600 PAD types in particular). It is always safe to set this option to
601 off, but this introduces a slight performance penalty. The default
604 * Python API Improvements
606 ** GDB provides the new class gdb.LazyString. This is useful in
607 some pretty-printing cases. The new method gdb.Value.lazy_string
608 provides a simple way to create objects of this type.
610 ** The fields returned by gdb.Type.fields now have an
611 `is_base_class' attribute.
613 ** The new method gdb.Type.range returns the range of an array type.
615 ** The new method gdb.parse_and_eval can be used to parse and
616 evaluate an expression.
621 Define a trace state variable.
624 Get the current value of a trace state variable.
627 Set desired tracing behavior upon disconnection.
630 Set the trace buffer to be linear or circular.
633 Get data about the tracepoints currently in use.
637 Process record now works correctly with hardware watchpoints.
639 Multiple bug fixes have been made to the mips-irix port, making it
640 much more reliable. In particular:
641 - Debugging threaded applications is now possible again. Previously,
642 GDB would hang while starting the program, or while waiting for
643 the program to stop at a breakpoint.
644 - Attaching to a running process no longer hangs.
645 - An error occurring while loading a core file has been fixed.
646 - Changing the value of the PC register now works again. This fixes
647 problems observed when using the "jump" command, or when calling
648 a function from GDB, or even when assigning a new value to $pc.
649 - With the "finish" and "return" commands, the return value for functions
650 returning a small array is now correctly printed.
651 - It is now possible to break on shared library code which gets executed
652 during a shared library init phase (code executed while executing
653 their .init section). Previously, the breakpoint would have no effect.
654 - GDB is now able to backtrace through the signal handler for
655 non-threaded programs.
657 PIE (Position Independent Executable) programs debugging is now supported.
658 This includes debugging execution of PIC (Position Independent Code) shared
659 libraries although for that, it should be possible to run such libraries as an
662 *** Changes in GDB 7.0
664 * GDB now has an interface for JIT compilation. Applications that
665 dynamically generate code can create symbol files in memory and register
666 them with GDB. For users, the feature should work transparently, and
667 for JIT developers, the interface is documented in the GDB manual in the
668 "JIT Compilation Interface" chapter.
670 * Tracepoints may now be conditional. The syntax is as for
671 breakpoints; either an "if" clause appended to the "trace" command,
672 or the "condition" command is available. GDB sends the condition to
673 the target for evaluation using the same bytecode format as is used
674 for tracepoint actions.
676 * The disassemble command now supports: an optional /r modifier, print the
677 raw instructions in hex as well as in symbolic form, and an optional /m
678 modifier to print mixed source+assembly.
680 * Process record and replay
682 In a architecture environment that supports ``process record and
683 replay'', ``process record and replay'' target can record a log of
684 the process execution, and replay it with both forward and reverse
687 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
688 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
689 set execution-direction {forward|reverse}, for targets that support
692 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
693 feature is available with a native GDB running on kernel version
696 * GDB now has support for multi-byte and wide character sets on the
697 target. Strings whose character type is wchar_t, char16_t, or
698 char32_t are now correctly printed. GDB supports wide- and unicode-
699 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
700 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
701 `printf'. This feature requires iconv to work properly; if your
702 system does not have a working iconv, GDB can use GNU libiconv. See
703 the installation instructions for more information.
705 * GDB now supports automatic retrieval of shared library files from
706 remote targets. To use this feature, specify a system root that begins
707 with the `remote:' prefix, either via the `set sysroot' command or via
708 the `--with-sysroot' configure-time option.
710 * "info sharedlibrary" now takes an optional regex of libraries to show,
711 and it now reports if a shared library has no debugging information.
713 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
714 now complete on file names.
716 * When completing in expressions, gdb will attempt to limit
717 completions to allowable structure or union fields, where appropriate.
718 For instance, consider:
720 # struct example { int f1; double f2; };
721 # struct example variable;
724 If the user types TAB at the end of this command line, the available
725 completions will be "f1" and "f2".
727 * Inlined functions are now supported. They show up in backtraces, and
728 the "step", "next", and "finish" commands handle them automatically.
730 * GDB now supports the token-splicing (##) and stringification (#)
731 operators when expanding macros. It also supports variable-arity
734 * GDB now supports inspecting extra signal information, exported by
735 the new $_siginfo convenience variable. The feature is currently
736 implemented on linux ARM, i386 and amd64.
738 * GDB can now display the VFP floating point registers and NEON vector
739 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
740 can provide these registers (requires Linux 2.6.30 or later). Remote
741 and simulator targets may also provide them.
746 Search memory for a sequence of bytes.
749 Turn off `+'/`-' protocol acknowledgments to permit more efficient
750 operation over reliable transport links. Use of this packet is
751 controlled by the `set remote noack-packet' command.
754 Kill the process with the specified process ID. Use this in preference
755 to `k' when multiprocess protocol extensions are supported.
758 Obtains additional operating system information
762 Read or write additional signal information.
764 * Removed remote protocol undocumented extension
766 An undocumented extension to the remote protocol's `S' stop reply
767 packet that permited the stub to pass a process id was removed.
768 Remote servers should use the `T' stop reply packet instead.
770 * GDB now supports multiple function calling conventions according to the
771 DWARF-2 DW_AT_calling_convention function attribute.
773 * The SH target utilizes the aforementioned change to distinguish between gcc
774 and Renesas calling convention. It also adds the new CLI commands
775 `set/show sh calling-convention'.
777 * GDB can now read compressed debug sections, as produced by GNU gold
778 with the --compress-debug-sections=zlib flag.
780 * 64-bit core files are now supported on AIX.
782 * Thread switching is now supported on Tru64.
784 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
785 which will be allocated using malloc later in program execution.
787 * The qXfer:libraries:read remote procotol packet now allows passing a
788 list of section offsets.
790 * On GNU/Linux, GDB can now attach to stopped processes. Several race
791 conditions handling signals delivered during attach or thread creation
792 have also been fixed.
794 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
795 From the user's standpoint, all unqualified instances of True and False
796 are treated as the standard definitions, regardless of context.
798 * GDB now parses C++ symbol and type names more flexibly. For
801 template<typename T> class C { };
804 GDB will now correctly handle all of:
806 ptype C<char const *>
808 ptype C<const char *>
811 * New features in the GDB remote stub, gdbserver
813 - The "--wrapper" command-line argument tells gdbserver to use a
814 wrapper program to launch programs for debugging.
816 - On PowerPC and S/390 targets, it is now possible to use a single
817 gdbserver executable to debug both 32-bit and 64-bit programs.
818 (This requires gdbserver itself to be built as a 64-bit executable.)
820 - gdbserver uses the new noack protocol mode for TCP connections to
821 reduce communications latency, if also supported and enabled in GDB.
823 - Support for the sparc64-linux-gnu target is now included in
826 - The amd64-linux build of gdbserver now supports debugging both
827 32-bit and 64-bit programs.
829 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
830 now support hardware watchpoints, and will use them automatically
835 GDB now has support for scripting using Python. Whether this is
836 available is determined at configure time.
838 New GDB commands can now be written in Python.
840 * Ada tasking support
842 Ada tasks can now be inspected in GDB. The following commands have
846 Print the list of Ada tasks.
848 Print detailed information about task number N.
850 Print the task number of the current task.
852 Switch the context of debugging to task number N.
854 * Support for user-defined prefixed commands. The "define" command can
855 add new commands to existing prefixes, e.g. "target".
857 * Multi-inferior, multi-process debugging.
859 GDB now has generalized support for multi-inferior debugging. See
860 "Debugging Multiple Inferiors" in the manual for more information.
861 Although availability still depends on target support, the command
862 set is more uniform now. The GNU/Linux specific multi-forks support
863 has been migrated to this new framework. This implied some user
864 visible changes; see "New commands" and also "Removed commands"
867 * Target descriptions can now describe the target OS ABI. See the
868 "Target Description Format" section in the user manual for more
871 * Target descriptions can now describe "compatible" architectures
872 to indicate that the target can execute applications for a different
873 architecture in addition to those for the main target architecture.
874 See the "Target Description Format" section in the user manual for
877 * Multi-architecture debugging.
879 GDB now includes general supports for debugging applications on
880 hybrid systems that use more than one single processor architecture
881 at the same time. Each such hybrid architecture still requires
882 specific support to be added. The only hybrid architecture supported
883 in this version of GDB is the Cell Broadband Engine.
885 * GDB now supports integrated debugging of Cell/B.E. applications that
886 use both the PPU and SPU architectures. To enable support for hybrid
887 Cell/B.E. debugging, you need to configure GDB to support both the
888 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
889 --enable-targets configure option.
891 * Non-stop mode debugging.
893 For some targets, GDB now supports an optional mode of operation in
894 which you can examine stopped threads while other threads continue
895 to execute freely. This is referred to as non-stop mode, with the
896 old mode referred to as all-stop mode. See the "Non-Stop Mode"
897 section in the user manual for more information.
899 To be able to support remote non-stop debugging, a remote stub needs
900 to implement the non-stop mode remote protocol extensions, as
901 described in the "Remote Non-Stop" section of the user manual. The
902 GDB remote stub, gdbserver, has been adjusted to support these
903 extensions on linux targets.
905 * New commands (for set/show, see "New options" below)
907 catch syscall [NAME(S) | NUMBER(S)]
908 Catch system calls. Arguments, which should be names of system
909 calls or their numbers, mean catch only those syscalls. Without
910 arguments, every syscall will be caught. When the inferior issues
911 any of the specified syscalls, GDB will stop and announce the system
912 call, both when it is called and when its call returns. This
913 feature is currently available with a native GDB running on the
914 Linux Kernel, under the following architectures: x86, x86_64,
915 PowerPC and PowerPC64.
917 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
919 Search memory for a sequence of bytes.
921 maint set python print-stack
922 maint show python print-stack
923 Show a stack trace when an error is encountered in a Python script.
926 Invoke CODE by passing it to the Python interpreter.
931 These allow macros to be defined, undefined, and listed
935 Show operating system information about processes.
938 List the inferiors currently under GDB's control.
941 Switch focus to inferior number NUM.
944 Detach from inferior number NUM.
947 Kill inferior number NUM.
952 show spu stop-on-load
953 Control whether to stop for new SPE threads during Cell/B.E. debugging.
955 set spu auto-flush-cache
956 show spu auto-flush-cache
957 Control whether to automatically flush the software-managed cache
958 during Cell/B.E. debugging.
960 set sh calling-convention
961 show sh calling-convention
962 Control the calling convention used when calling SH target functions.
966 Control display of timestamps with GDB debugging output.
968 set disassemble-next-line
969 show disassemble-next-line
970 Control display of disassembled source lines or instructions when
973 set remote noack-packet
974 show remote noack-packet
975 Set/show the use of remote protocol QStartNoAckMode packet. See above
976 under "New remote packets."
978 set remote query-attached-packet
979 show remote query-attached-packet
980 Control use of remote protocol `qAttached' (query-attached) packet.
982 set remote read-siginfo-object
983 show remote read-siginfo-object
984 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
987 set remote write-siginfo-object
988 show remote write-siginfo-object
989 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
992 set remote reverse-continue
993 show remote reverse-continue
994 Control use of remote protocol 'bc' (reverse-continue) packet.
996 set remote reverse-step
997 show remote reverse-step
998 Control use of remote protocol 'bs' (reverse-step) packet.
1000 set displaced-stepping
1001 show displaced-stepping
1002 Control displaced stepping mode. Displaced stepping is a way to
1003 single-step over breakpoints without removing them from the debuggee.
1004 Also known as "out-of-line single-stepping".
1007 show debug displaced
1008 Control display of debugging info for displaced stepping.
1010 maint set internal-error
1011 maint show internal-error
1012 Control what GDB does when an internal error is detected.
1014 maint set internal-warning
1015 maint show internal-warning
1016 Control what GDB does when an internal warning is detected.
1021 Use a wrapper program to launch programs for debugging.
1023 set multiple-symbols (all|ask|cancel)
1024 show multiple-symbols
1025 The value of this variable can be changed to adjust the debugger behavior
1026 when an expression or a breakpoint location contains an ambiguous symbol
1027 name (an overloaded function name, for instance).
1029 set breakpoint always-inserted
1030 show breakpoint always-inserted
1031 Keep breakpoints always inserted in the target, as opposed to inserting
1032 them when resuming the target, and removing them when the target stops.
1033 This option can improve debugger performance on slow remote targets.
1035 set arm fallback-mode (arm|thumb|auto)
1036 show arm fallback-mode
1037 set arm force-mode (arm|thumb|auto)
1039 These commands control how ARM GDB determines whether instructions
1040 are ARM or Thumb. The default for both settings is auto, which uses
1041 the current CPSR value for instructions without symbols; previous
1042 versions of GDB behaved as if "set arm fallback-mode arm".
1044 set disable-randomization
1045 show disable-randomization
1046 Standalone programs run with the virtual address space randomization enabled
1047 by default on some platforms. This option keeps the addresses stable across
1048 multiple debugging sessions.
1052 Control whether other threads are stopped or not when some thread hits
1057 Requests that asynchronous execution is enabled in the target, if available.
1058 In this case, it's possible to resume target in the background, and interact
1059 with GDB while the target is running. "show target-async" displays the
1060 current state of asynchronous execution of the target.
1062 set target-wide-charset
1063 show target-wide-charset
1064 The target-wide-charset is the name of the character set that GDB
1065 uses when printing characters whose type is wchar_t.
1067 set tcp auto-retry (on|off)
1069 set tcp connect-timeout
1070 show tcp connect-timeout
1071 These commands allow GDB to retry failed TCP connections to a remote stub
1072 with a specified timeout period; this is useful if the stub is launched
1073 in parallel with GDB but may not be ready to accept connections immediately.
1075 set libthread-db-search-path
1076 show libthread-db-search-path
1077 Control list of directories which GDB will search for appropriate
1080 set schedule-multiple (on|off)
1081 show schedule-multiple
1082 Allow GDB to resume all threads of all processes or only threads of
1083 the current process.
1087 Use more aggressive caching for accesses to the stack. This improves
1088 performance of remote debugging (particularly backtraces) without
1089 affecting correctness.
1091 set interactive-mode (on|off|auto)
1092 show interactive-mode
1093 Control whether GDB runs in interactive mode (on) or not (off).
1094 When in interactive mode, GDB waits for the user to answer all
1095 queries. Otherwise, GDB does not wait and assumes the default
1096 answer. When set to auto (the default), GDB determines which
1097 mode to use based on the stdin settings.
1102 For program forks, this is replaced by the new more generic `info
1103 inferiors' command. To list checkpoints, you can still use the
1104 `info checkpoints' command, which was an alias for the `info forks'
1108 Replaced by the new `inferior' command. To switch between
1109 checkpoints, you can still use the `restart' command, which was an
1110 alias for the `fork' command.
1113 This is removed, since some targets don't have a notion of
1114 processes. To switch between processes, you can still use the
1115 `inferior' command using GDB's own inferior number.
1118 For program forks, this is replaced by the new more generic `kill
1119 inferior' command. To delete a checkpoint, you can still use the
1120 `delete checkpoint' command, which was an alias for the `delete
1124 For program forks, this is replaced by the new more generic `detach
1125 inferior' command. To detach a checkpoint, you can still use the
1126 `detach checkpoint' command, which was an alias for the `detach
1129 * New native configurations
1131 x86/x86_64 Darwin i[34567]86-*-darwin*
1133 x86_64 MinGW x86_64-*-mingw*
1137 Lattice Mico32 lm32-*
1138 x86 DICOS i[34567]86-*-dicos*
1139 x86_64 DICOS x86_64-*-dicos*
1142 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1143 (mingw32ce) debugging.
1149 These commands were actually not implemented on any target.
1151 *** Changes in GDB 6.8
1153 * New native configurations
1155 NetBSD/hppa hppa*-*netbsd*
1156 Xtensa GNU/Linux xtensa*-*-linux*
1160 NetBSD/hppa hppa*-*-netbsd*
1161 Xtensa GNU/Lunux xtensa*-*-linux*
1163 * Change in command line behavior -- corefiles vs. process ids.
1165 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1166 attaching to process NUMBER fails, GDB no longer attempts to open a
1167 core file named NUMBER. Attaching to a program using the -c option
1168 is no longer supported. Instead, use the '-p' or '--pid' options.
1170 * GDB can now be built as a native debugger for debugging Windows x86
1171 (mingw32) Portable Executable (PE) programs.
1173 * Pending breakpoints no longer change their number when their address
1176 * GDB now supports breakpoints with multiple locations,
1177 including breakpoints on C++ constructors, inside C++ templates,
1178 and in inlined functions.
1180 * GDB's ability to debug optimized code has been improved. GDB more
1181 accurately identifies function bodies and lexical blocks that occupy
1182 more than one contiguous range of addresses.
1184 * Target descriptions can now describe registers for PowerPC.
1186 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1187 registers on PowerPC targets.
1189 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1190 targets even when the libthread_db library is not available.
1192 * The GDB remote stub, gdbserver, now supports the new file transfer
1193 commands (remote put, remote get, and remote delete).
1195 * The GDB remote stub, gdbserver, now supports run and attach in
1196 extended-remote mode.
1198 * hppa*64*-*-hpux11* target broken
1199 The debugger is unable to start a program and fails with the following
1200 error: "Error trying to get information about dynamic linker".
1201 The gdb-6.7 release is also affected.
1203 * GDB now supports the --enable-targets= configure option to allow
1204 building a single GDB executable that supports multiple remote
1205 target architectures.
1207 * GDB now supports debugging C and C++ programs which use the
1208 Decimal Floating Point extension. In addition, the PowerPC target
1209 now has a set of pseudo-registers to inspect decimal float values
1210 stored in two consecutive float registers.
1212 * The -break-insert MI command can optionally create pending
1215 * Improved support for debugging Ada
1216 Many improvements to the Ada language support have been made. These
1218 - Better support for Ada2005 interface types
1219 - Improved handling of arrays and slices in general
1220 - Better support for Taft-amendment types
1221 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1223 - Improved command completion in Ada
1226 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1231 set print frame-arguments (all|scalars|none)
1232 show print frame-arguments
1233 The value of this variable can be changed to control which argument
1234 values should be printed by the debugger when displaying a frame.
1239 Transfer files to and from a remote target, and delete remote files.
1246 Transfer files to and from a remote target, and delete remote files.
1248 * New remote packets
1255 Open, close, read, write, and delete files on the remote system.
1258 Attach to an existing process on the remote system, in extended-remote
1262 Run a new process on the remote system, in extended-remote mode.
1264 *** Changes in GDB 6.7
1266 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1267 bfd, libiberty and opcodes, as revealed by static analysis donated by
1268 Coverity, Inc. (http://scan.coverity.com).
1270 * When looking up multiply-defined global symbols, GDB will now prefer the
1271 symbol definition in the current shared library if it was built using the
1272 -Bsymbolic linker option.
1274 * When the Text User Interface (TUI) is not configured, GDB will now
1275 recognize the -tui command-line option and print a message that the TUI
1278 * The GDB remote stub, gdbserver, now has lower overhead for high
1279 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1281 * GDB for MIPS targets now autodetects whether a remote target provides
1282 32-bit or 64-bit register values.
1284 * Support for C++ member pointers has been improved.
1286 * GDB now understands XML target descriptions, which specify the
1287 target's overall architecture. GDB can read a description from
1288 a local file or over the remote serial protocol.
1290 * Vectors of single-byte data use a new integer type which is not
1291 automatically displayed as character or string data.
1293 * The /s format now works with the print command. It displays
1294 arrays of single-byte integers and pointers to single-byte integers
1297 * Target descriptions can now describe target-specific registers,
1298 for architectures which have implemented the support (currently
1299 only ARM, M68K, and MIPS).
1301 * GDB and the GDB remote stub, gdbserver, now support the XScale
1304 * The GDB remote stub, gdbserver, has been updated to support
1305 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1306 has been rewritten to use the standard GDB remote protocol.
1308 * GDB can now step into C++ functions which are called through thunks.
1310 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1312 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1313 layout. It also supports a TextSeg= and DataSeg= response when only
1314 segment base addresses (rather than offsets) are available.
1316 * The /i format now outputs any trailing branch delay slot instructions
1317 immediately following the last instruction within the count specified.
1319 * The GDB remote protocol "T" stop reply packet now supports a
1320 "library" response. Combined with the new "qXfer:libraries:read"
1321 packet, this response allows GDB to debug shared libraries on targets
1322 where the operating system manages the list of loaded libraries (e.g.
1323 Windows and SymbianOS).
1325 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1326 (DLLs) on Windows and Windows CE targets.
1328 * GDB now supports a faster verification that a .debug file matches its binary
1329 according to its build-id signature, if the signature is present.
1335 Enable or disable hardware flow control (RTS/CTS) on the serial port
1336 when debugging using remote targets.
1338 set mem inaccessible-by-default
1339 show mem inaccessible-by-default
1340 If the target supplies a memory map, for instance via the remote
1341 protocol's "qXfer:memory-map:read" packet, setting this variable
1342 prevents GDB from accessing memory outside the memory map. This
1343 is useful for targets with memory mapped registers or which react
1344 badly to accesses of unmapped address space.
1346 set breakpoint auto-hw
1347 show breakpoint auto-hw
1348 If the target supplies a memory map, for instance via the remote
1349 protocol's "qXfer:memory-map:read" packet, setting this variable
1350 lets GDB use hardware breakpoints automatically for memory regions
1351 where it can not use software breakpoints. This covers both the
1352 "break" command and internal breakpoints used for other commands
1353 including "next" and "finish".
1356 catch exception unhandled
1357 Stop the program execution when Ada exceptions are raised.
1360 Stop the program execution when an Ada assertion failed.
1364 Set an alternate system root for target files. This is a more
1365 general version of "set solib-absolute-prefix", which is now
1366 an alias to "set sysroot".
1369 Provide extended SPU facility status information. This set of
1370 commands is available only when debugging the Cell/B.E. SPU
1373 * New native configurations
1375 OpenBSD/sh sh*-*openbsd*
1378 unset tdesc filename
1380 Use the specified local file as an XML target description, and do
1381 not query the target for its built-in description.
1385 OpenBSD/sh sh*-*-openbsd*
1386 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1387 Toshiba Media Processor mep-elf
1389 * New remote packets
1392 Ignore the specified signals; pass them directly to the debugged program
1393 without stopping other threads or reporting them to GDB.
1395 qXfer:features:read:
1396 Read an XML target description from the target, which describes its
1401 Read or write contents of an spufs file on the target system. These
1402 packets are available only on the Cell/B.E. SPU architecture.
1404 qXfer:libraries:read:
1405 Report the loaded shared libraries. Combined with new "T" packet
1406 response, this packet allows GDB to debug shared libraries on
1407 targets where the operating system manages the list of loaded
1408 libraries (e.g. Windows and SymbianOS).
1412 Support for these obsolete configurations has been removed.
1420 i[34567]86-*-lynxos*
1421 i[34567]86-*-netware*
1422 i[34567]86-*-sco3.2v5*
1423 i[34567]86-*-sco3.2v4*
1425 i[34567]86-*-sysv4.2*
1428 i[34567]86-*-unixware2*
1429 i[34567]86-*-unixware*
1438 * Other removed features
1445 Various m68k-only ROM monitors.
1452 Various Renesas ROM monitors and debugging interfaces for SH and
1457 Support for a Macraigor serial interface to on-chip debugging.
1458 GDB does not directly support the newer parallel or USB
1463 A debug information format. The predecessor to DWARF 2 and
1464 DWARF 3, which are still supported.
1466 Support for the HP aCC compiler on HP-UX/PA-RISC
1468 SOM-encapsulated symbolic debugging information, automatic
1469 invocation of pxdb, and the aCC custom C++ ABI. This does not
1470 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1471 with aCC can still be debugged on an assembly level.
1473 MIPS ".pdr" sections
1475 A MIPS-specific format used to describe stack frame layout
1476 in debugging information.
1480 GDB could work with an older version of Guile to debug
1481 the interpreter and Scheme programs running in it.
1483 set mips stack-arg-size
1484 set mips saved-gpreg-size
1486 Use "set mips abi" to control parameter passing for MIPS.
1488 *** Changes in GDB 6.6
1493 Cell Broadband Engine SPU spu-elf
1495 * GDB can now be configured as a cross-debugger targeting native Windows
1496 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1497 running on a Windows system over TCP/IP to debug Windows programs.
1499 * The GDB remote stub, gdbserver, has been updated to support Windows and
1500 Cygwin debugging. Both single-threaded and multi-threaded programs are
1503 * The "set trust-readonly-sections" command works again. This command was
1504 broken in GDB 6.3, 6.4, and 6.5.
1506 * The "load" command now supports writing to flash memory, if the remote
1507 stub provides the required support.
1509 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1510 longer requires symbolic debug information (e.g. DWARF-2).
1515 unset substitute-path
1516 show substitute-path
1517 Manage a list of substitution rules that GDB uses to rewrite the name
1518 of the directories where the sources are located. This can be useful
1519 for instance when the sources were moved to a different location
1520 between compilation and debugging.
1524 Print each CLI command as it is executed. Each command is prefixed with
1525 a number of `+' symbols representing the nesting depth.
1526 The source command now has a `-v' option to enable the same feature.
1530 The ARM Demon monitor support (RDP protocol, "target rdp").
1532 Kernel Object Display, an embedded debugging feature which only worked with
1533 an obsolete version of Cisco IOS.
1535 The 'set download-write-size' and 'show download-write-size' commands.
1537 * New remote packets
1540 Tell a stub about GDB client features, and request remote target features.
1541 The first feature implemented is PacketSize, which allows the target to
1542 specify the size of packets it can handle - to minimize the number of
1543 packets required and improve performance when connected to a remote
1547 Fetch an OS auxilliary vector from the remote stub. This packet is a
1548 more efficient replacement for qPart:auxv:read.
1550 qXfer:memory-map:read:
1551 Fetch a memory map from the remote stub, including information about
1552 RAM, ROM, and flash memory devices.
1557 Erase and program a flash memory device.
1559 * Removed remote packets
1562 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1563 used it, and only gdbserver implemented it.
1565 *** Changes in GDB 6.5
1569 Renesas M32C/M16C m32c-elf
1571 Morpho Technologies ms1 ms1-elf
1575 init-if-undefined Initialize a convenience variable, but
1576 only if it doesn't already have a value.
1578 The following commands are presently only implemented for native GNU/Linux:
1580 checkpoint Save a snapshot of the program state.
1582 restart <n> Return the program state to a
1583 previously saved state.
1585 info checkpoints List currently saved checkpoints.
1587 delete-checkpoint <n> Delete a previously saved checkpoint.
1589 set|show detach-on-fork Tell gdb whether to detach from a newly
1590 forked process, or to keep debugging it.
1592 info forks List forks of the user program that
1593 are available to be debugged.
1595 fork <n> Switch to debugging one of several
1596 forks of the user program that are
1597 available to be debugged.
1599 delete-fork <n> Delete a fork from the list of forks
1600 that are available to be debugged (and
1601 kill the forked process).
1603 detach-fork <n> Delete a fork from the list of forks
1604 that are available to be debugged (and
1605 allow the process to continue).
1609 Morpho Technologies ms2 ms1-elf
1611 * Improved Windows host support
1613 GDB now builds as a cross debugger hosted on i686-mingw32, including
1614 native console support, and remote communications using either
1615 network sockets or serial ports.
1617 * Improved Modula-2 language support
1619 GDB can now print most types in the Modula-2 syntax. This includes:
1620 basic types, set types, record types, enumerated types, range types,
1621 pointer types and ARRAY types. Procedure var parameters are correctly
1622 printed and hexadecimal addresses and character constants are also
1623 written in the Modula-2 syntax. Best results can be obtained by using
1624 GNU Modula-2 together with the -gdwarf-2 command line option.
1628 The ARM rdi-share module.
1630 The Netware NLM debug server.
1632 *** Changes in GDB 6.4
1634 * New native configurations
1636 OpenBSD/arm arm*-*-openbsd*
1637 OpenBSD/mips64 mips64-*-openbsd*
1641 Morpho Technologies ms1 ms1-elf
1643 * New command line options
1645 --batch-silent As for --batch, but totally silent.
1646 --return-child-result The debugger will exist with the same value
1647 the child (debugged) program exited with.
1648 --eval-command COMMAND, -ex COMMAND
1649 Execute a single GDB CLI command. This may be
1650 specified multiple times and in conjunction
1651 with the --command (-x) option.
1653 * Deprecated commands removed
1655 The following commands, that were deprecated in 2000, have been
1659 set|show arm disassembly-flavor set|show arm disassembler
1660 othernames set arm disassembler
1661 set|show remotedebug set|show debug remote
1662 set|show archdebug set|show debug arch
1663 set|show eventdebug set|show debug event
1666 * New BSD user-level threads support
1668 It is now possible to debug programs using the user-level threads
1669 library on OpenBSD and FreeBSD. Currently supported (target)
1672 FreeBSD/amd64 x86_64-*-freebsd*
1673 FreeBSD/i386 i386-*-freebsd*
1674 OpenBSD/i386 i386-*-openbsd*
1676 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1677 are not yet supported.
1679 * New support for Matsushita MN10300 w/sim added
1680 (Work in progress). mn10300-elf.
1682 * REMOVED configurations and files
1684 VxWorks and the XDR protocol *-*-vxworks
1685 Motorola MCORE mcore-*-*
1686 National Semiconductor NS32000 ns32k-*-*
1688 * New "set print array-indexes" command
1690 After turning this setting "on", GDB prints the index of each element
1691 when displaying arrays. The default is "off" to preserve the previous
1694 * VAX floating point support
1696 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1698 * User-defined command support
1700 In addition to using $arg0..$arg9 for argument passing, it is now possible
1701 to use $argc to determine now many arguments have been passed. See the
1702 section on user-defined commands in the user manual for more information.
1704 *** Changes in GDB 6.3:
1706 * New command line option
1708 GDB now accepts -l followed by a number to set the timeout for remote
1711 * GDB works with GCC -feliminate-dwarf2-dups
1713 GDB now supports a more compact representation of DWARF-2 debug
1714 information using DW_FORM_ref_addr references. These are produced
1715 by GCC with the option -feliminate-dwarf2-dups and also by some
1716 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1717 to use -feliminate-dwarf2-dups.
1719 * Internationalization
1721 When supported by the host system, GDB will be built with
1722 internationalization (libintl). The task of marking up the sources is
1723 continued, we're looking forward to our first translation.
1727 Initial support for debugging programs compiled with the GNAT
1728 implementation of the Ada programming language has been integrated
1729 into GDB. In this release, support is limited to expression evaluation.
1731 * New native configurations
1733 GNU/Linux/m32r m32r-*-linux-gnu
1737 GDB's remote protocol now includes support for the 'p' packet. This
1738 packet is used to fetch individual registers from a remote inferior.
1740 * END-OF-LIFE registers[] compatibility module
1742 GDB's internal register infrastructure has been completely rewritten.
1743 The new infrastructure making possible the implementation of key new
1744 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1747 GDB 6.3 will be the last release to include the the registers[]
1748 compatibility module that allowed out-of-date configurations to
1749 continue to work. This change directly impacts the following
1759 powerpc bdm protocol
1761 Unless there is activity to revive these configurations, they will be
1762 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1764 * OBSOLETE configurations and files
1766 Configurations that have been declared obsolete in this release have
1767 been commented out. Unless there is activity to revive these
1768 configurations, the next release of GDB will have their sources
1769 permanently REMOVED.
1778 *** Changes in GDB 6.2.1:
1780 * MIPS `break main; run' gave an heuristic-fence-post warning
1782 When attempting to run even a simple program, a warning about
1783 heuristic-fence-post being hit would be reported. This problem has
1786 * MIPS IRIX 'long double' crashed GDB
1788 When examining a long double variable, GDB would get a segmentation
1789 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1790 IRIX long double values).
1794 A bug in the VAX stack code was causing problems with the "next"
1795 command. This problem has been fixed.
1797 *** Changes in GDB 6.2:
1799 * Fix for ``many threads''
1801 On GNU/Linux systems that use the NPTL threads library, a program
1802 rapidly creating and deleting threads would confuse GDB leading to the
1805 ptrace: No such process.
1806 thread_db_get_info: cannot get thread info: generic error
1808 This problem has been fixed.
1810 * "-async" and "-noasync" options removed.
1812 Support for the broken "-noasync" option has been removed (it caused
1815 * New ``start'' command.
1817 This command runs the program until the begining of the main procedure.
1819 * New BSD Kernel Data Access Library (libkvm) interface
1821 Using ``target kvm'' it is now possible to debug kernel core dumps and
1822 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1823 platforms. Currently supported (native-only) configurations are:
1825 FreeBSD/amd64 x86_64-*-freebsd*
1826 FreeBSD/i386 i?86-*-freebsd*
1827 NetBSD/i386 i?86-*-netbsd*
1828 NetBSD/m68k m68*-*-netbsd*
1829 NetBSD/sparc sparc-*-netbsd*
1830 OpenBSD/amd64 x86_64-*-openbsd*
1831 OpenBSD/i386 i?86-*-openbsd*
1832 OpenBSD/m68k m68*-openbsd*
1833 OpenBSD/sparc sparc-*-openbsd*
1835 * Signal trampoline code overhauled
1837 Many generic problems with GDB's signal handling code have been fixed.
1838 These include: backtraces through non-contiguous stacks; recognition
1839 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1840 call; backtrace through a signal trampoline; step into and out of
1841 signal handlers; and single-stepping in the signal trampoline.
1843 Please note that kernel bugs are a limiting factor here. These
1844 features have been shown to work on an s390 GNU/Linux system that
1845 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1847 * Cygwin support for DWARF 2 added.
1849 * New native configurations
1851 GNU/Linux/hppa hppa*-*-linux*
1852 OpenBSD/hppa hppa*-*-openbsd*
1853 OpenBSD/m68k m68*-*-openbsd*
1854 OpenBSD/m88k m88*-*-openbsd*
1855 OpenBSD/powerpc powerpc-*-openbsd*
1856 NetBSD/vax vax-*-netbsd*
1857 OpenBSD/vax vax-*-openbsd*
1859 * END-OF-LIFE frame compatibility module
1861 GDB's internal frame infrastructure has been completely rewritten.
1862 The new infrastructure making it possible to support key new features
1863 including DWARF 2 Call Frame Information. To aid in the task of
1864 migrating old configurations to this new infrastructure, a
1865 compatibility module, that allowed old configurations to continue to
1866 work, was also included.
1868 GDB 6.2 will be the last release to include this frame compatibility
1869 module. This change directly impacts the following configurations:
1879 Unless there is activity to revive these configurations, they will be
1880 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1882 * REMOVED configurations and files
1884 Sun 3, running SunOS 3 m68*-*-sunos3*
1885 Sun 3, running SunOS 4 m68*-*-sunos4*
1886 Sun 2, running SunOS 3 m68000-*-sunos3*
1887 Sun 2, running SunOS 4 m68000-*-sunos4*
1888 Motorola 680x0 running LynxOS m68*-*-lynxos*
1889 AT&T 3b1/Unix pc m68*-att-*
1890 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1891 decstation mips-dec-* mips-little-*
1892 riscos mips-*-riscos* mips-*-sysv*
1893 sonymips mips-sony-*
1894 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1896 *** Changes in GDB 6.1.1:
1898 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1900 The TUI (Text-mode User Interface) is now built as part of a default
1901 GDB configuration. It is enabled by either selecting the TUI with the
1902 command line option "-i=tui" or by running the separate "gdbtui"
1903 program. For more information on the TUI, see the manual "Debugging
1906 * Pending breakpoint support (also included in GDB 6.1)
1908 Support has been added to allow you to specify breakpoints in shared
1909 libraries that have not yet been loaded. If a breakpoint location
1910 cannot be found, and the "breakpoint pending" option is set to auto,
1911 GDB queries you if you wish to make the breakpoint pending on a future
1912 shared-library load. If and when GDB resolves the breakpoint symbol,
1913 the pending breakpoint is removed as one or more regular breakpoints
1916 Pending breakpoints are very useful for GCJ Java debugging.
1918 * Fixed ISO-C build problems
1920 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1921 non ISO-C code that stopped them being built using a more strict ISO-C
1922 compiler (e.g., IBM's C compiler).
1924 * Fixed build problem on IRIX 5
1926 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1927 wasn't able to compile compile on an IRIX 5 system.
1929 * Added execute permission to gdb/gdbserver/configure
1931 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1932 permission. This bug would cause configure to fail on a number of
1933 systems (Solaris, IRIX). Ref: server/519.
1935 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1937 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1938 has been updated to use constant array sizes.
1940 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1942 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1943 its generated DWARF Call Frame Info. This encoding was causing GDB to
1944 panic, that panic has been fixed. Ref: gdb/1628.
1946 * Fixed a problem when examining parameters in shared library code.
1948 When examining parameters in optimized shared library code generated
1949 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1950 not available''. GDB now correctly displays the variable's value.
1952 *** Changes in GDB 6.1:
1954 * Removed --with-mmalloc
1956 Support for the mmalloc memory manager has been removed, as it
1957 conflicted with the internal gdb byte cache.
1959 * Changes in AMD64 configurations
1961 The AMD64 target now includes the %cs and %ss registers. As a result
1962 the AMD64 remote protocol has changed; this affects the floating-point
1963 and SSE registers. If you rely on those registers for your debugging,
1964 you should upgrade gdbserver on the remote side.
1966 * Revised SPARC target
1968 The SPARC target has been completely revised, incorporating the
1969 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1970 support for LynxOS and SunOS 4 has been dropped. Calling functions
1971 from within GDB on operating systems with a non-executable stack
1972 (Solaris, OpenBSD) now works.
1976 GDB has a new C++ demangler which does a better job on the mangled
1977 names generated by current versions of g++. It also runs faster, so
1978 with this and other changes gdb should now start faster on large C++
1981 * DWARF 2 Location Expressions
1983 GDB support for location expressions has been extended to support function
1984 arguments and frame bases. Older versions of GDB could crash when they
1987 * C++ nested types and namespaces
1989 GDB's support for nested types and namespaces in C++ has been
1990 improved, especially if you use the DWARF 2 debugging format. (This
1991 is the default for recent versions of GCC on most platforms.)
1992 Specifically, if you have a class "Inner" defined within a class or
1993 namespace "Outer", then GDB realizes that the class's name is
1994 "Outer::Inner", not simply "Inner". This should greatly reduce the
1995 frequency of complaints about not finding RTTI symbols. In addition,
1996 if you are stopped at inside of a function defined within a namespace,
1997 GDB modifies its name lookup accordingly.
1999 * New native configurations
2001 NetBSD/amd64 x86_64-*-netbsd*
2002 OpenBSD/amd64 x86_64-*-openbsd*
2003 OpenBSD/alpha alpha*-*-openbsd*
2004 OpenBSD/sparc sparc-*-openbsd*
2005 OpenBSD/sparc64 sparc64-*-openbsd*
2007 * New debugging protocols
2009 M32R with SDI protocol m32r-*-elf*
2011 * "set prompt-escape-char" command deleted.
2013 The command "set prompt-escape-char" has been deleted. This command,
2014 and its very obscure effet on GDB's prompt, was never documented,
2015 tested, nor mentioned in the NEWS file.
2017 * OBSOLETE configurations and files
2019 Configurations that have been declared obsolete in this release have
2020 been commented out. Unless there is activity to revive these
2021 configurations, the next release of GDB will have their sources
2022 permanently REMOVED.
2024 Sun 3, running SunOS 3 m68*-*-sunos3*
2025 Sun 3, running SunOS 4 m68*-*-sunos4*
2026 Sun 2, running SunOS 3 m68000-*-sunos3*
2027 Sun 2, running SunOS 4 m68000-*-sunos4*
2028 Motorola 680x0 running LynxOS m68*-*-lynxos*
2029 AT&T 3b1/Unix pc m68*-att-*
2030 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2031 decstation mips-dec-* mips-little-*
2032 riscos mips-*-riscos* mips-*-sysv*
2033 sonymips mips-sony-*
2034 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2036 * REMOVED configurations and files
2038 SGI Irix-4.x mips-sgi-irix4 or iris4
2039 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2040 Z8000 simulator z8k-zilog-none or z8ksim
2041 Matsushita MN10200 w/simulator mn10200-*-*
2042 H8/500 simulator h8500-hitachi-hms or h8500hms
2043 HP/PA running BSD hppa*-*-bsd*
2044 HP/PA running OSF/1 hppa*-*-osf*
2045 HP/PA Pro target hppa*-*-pro*
2046 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2047 386BSD i[3456]86-*-bsd*
2048 Sequent family i[3456]86-sequent-sysv4*
2049 i[3456]86-sequent-sysv*
2050 i[3456]86-sequent-bsd*
2051 SPARC running LynxOS sparc-*-lynxos*
2052 SPARC running SunOS 4 sparc-*-sunos4*
2053 Tsqware Sparclet sparclet-*-*
2054 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2056 *** Changes in GDB 6.0:
2060 Support for debugging the Objective-C programming language has been
2061 integrated into GDB.
2063 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2065 DWARF 2's Call Frame Information makes available compiler generated
2066 information that more exactly describes the program's run-time stack.
2067 By using this information, GDB is able to provide more robust stack
2070 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2071 have been updated to use a new backtrace mechanism which includes
2072 DWARF 2 CFI support.
2076 GDB's remote protocol has been extended to include support for hosted
2077 file I/O (where the remote target uses GDB's file system). See GDB's
2078 remote protocol documentation for details.
2080 * All targets using the new architecture framework.
2082 All of GDB's targets have been updated to use the new internal
2083 architecture framework. The way is now open for future GDB releases
2084 to include cross-architecture native debugging support (i386 on amd64,
2087 * GNU/Linux's Thread Local Storage (TLS)
2089 GDB now includes support for for the GNU/Linux implementation of
2090 per-thread variables.
2092 * GNU/Linux's Native POSIX Thread Library (NPTL)
2094 GDB's thread code has been updated to work with either the new
2095 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2097 * Separate debug info.
2099 GDB, in conjunction with BINUTILS, now supports a mechanism for
2100 automatically loading debug information from a separate file. Instead
2101 of shipping full debug and non-debug versions of system libraries,
2102 system integrators can now instead ship just the stripped libraries
2103 and optional debug files.
2105 * DWARF 2 Location Expressions
2107 DWARF 2 Location Expressions allow the compiler to more completely
2108 describe the location of variables (even in optimized code) to the
2111 GDB now includes preliminary support for location expressions (support
2112 for DW_OP_piece is still missing).
2116 A number of long standing bugs that caused GDB to die while starting a
2117 Java application have been fixed. GDB's Java support is now
2118 considered "useable".
2120 * GNU/Linux support for fork, vfork, and exec.
2122 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2123 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2126 * GDB supports logging output to a file
2128 There are two new commands, "set logging" and "show logging", which can be
2129 used to capture GDB's output to a file.
2131 * The meaning of "detach" has changed for gdbserver
2133 The "detach" command will now resume the application, as documented. To
2134 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2137 * d10v, m68hc11 `regs' command deprecated
2139 The `info registers' command has been updated so that it displays the
2140 registers using a format identical to the old `regs' command.
2144 A new command, "maint set profile on/off", has been added. This command can
2145 be used to enable or disable profiling while running GDB, to profile a
2146 session or a set of commands. In addition there is a new configure switch,
2147 "--enable-profiling", which will cause GDB to be compiled with profiling
2148 data, for more informative profiling results.
2150 * Default MI syntax changed to "mi2".
2152 The default MI (machine interface) syntax, enabled by the command line
2153 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2154 "mi1", can be enabled by specifying the option "-i=mi1".
2156 Support for the original "mi0" syntax (included in GDB 5.0) has been
2159 Fix for gdb/192: removed extraneous space when displaying frame level.
2160 Fix for gdb/672: update changelist is now output in mi list format.
2161 Fix for gdb/702: a -var-assign that updates the value now shows up
2162 in a subsequent -var-update.
2164 * New native configurations.
2166 FreeBSD/amd64 x86_64-*-freebsd*
2168 * Multi-arched targets.
2170 HP/PA HPUX11 hppa*-*-hpux*
2171 Renesas M32R/D w/simulator m32r-*-elf*
2173 * OBSOLETE configurations and files
2175 Configurations that have been declared obsolete in this release have
2176 been commented out. Unless there is activity to revive these
2177 configurations, the next release of GDB will have their sources
2178 permanently REMOVED.
2180 Z8000 simulator z8k-zilog-none or z8ksim
2181 Matsushita MN10200 w/simulator mn10200-*-*
2182 H8/500 simulator h8500-hitachi-hms or h8500hms
2183 HP/PA running BSD hppa*-*-bsd*
2184 HP/PA running OSF/1 hppa*-*-osf*
2185 HP/PA Pro target hppa*-*-pro*
2186 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2187 Sequent family i[3456]86-sequent-sysv4*
2188 i[3456]86-sequent-sysv*
2189 i[3456]86-sequent-bsd*
2190 Tsqware Sparclet sparclet-*-*
2191 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2193 * REMOVED configurations and files
2196 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2197 IBM AIX PS/2 i[3456]86-*-aix
2198 i386 running Mach 3.0 i[3456]86-*-mach3*
2199 i386 running Mach i[3456]86-*-mach*
2200 i386 running OSF/1 i[3456]86-*osf1mk*
2201 HP/Apollo 68k Family m68*-apollo*-sysv*,
2203 m68*-hp-bsd*, m68*-hp-hpux*
2204 Argonaut Risc Chip (ARC) arc-*-*
2205 Mitsubishi D30V d30v-*-*
2206 Fujitsu FR30 fr30-*-elf*
2207 OS/9000 i[34]86-*-os9k
2208 I960 with MON960 i960-*-coff
2210 * MIPS $fp behavior changed
2212 The convenience variable $fp, for the MIPS, now consistently returns
2213 the address of the current frame's base. Previously, depending on the
2214 context, $fp could refer to either $sp or the current frame's base
2215 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2216 The GNU Source-Level Debugger''.
2218 *** Changes in GDB 5.3:
2220 * GNU/Linux shared library multi-threaded performance improved.
2222 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2223 `/proc', in preference to `ptrace' for memory reads. This may result
2224 in an improvement in the start-up time of multi-threaded, shared
2225 library applications when run under GDB. One GDB user writes: ``loads
2226 shared libs like mad''.
2228 * ``gdbserver'' now supports multi-threaded applications on some targets
2230 Support for debugging multi-threaded applications which use
2231 the GNU/Linux LinuxThreads package has been added for
2232 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2233 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2235 * GDB now supports C/C++ preprocessor macros.
2237 GDB now expands preprocessor macro invocations in C/C++ expressions,
2238 and provides various commands for showing macro definitions and how
2241 The new command `macro expand EXPRESSION' expands any macro
2242 invocations in expression, and shows the result.
2244 The new command `show macro MACRO-NAME' shows the definition of the
2245 macro named MACRO-NAME, and where it was defined.
2247 Most compilers don't include information about macros in the debugging
2248 information by default. In GCC 3.1, for example, you need to compile
2249 your program with the options `-gdwarf-2 -g3'. If the macro
2250 information is present in the executable, GDB will read it.
2252 * Multi-arched targets.
2254 DEC Alpha (partial) alpha*-*-*
2255 DEC VAX (partial) vax-*-*
2257 National Semiconductor NS32000 (partial) ns32k-*-*
2258 Motorola 68000 (partial) m68k-*-*
2259 Motorola MCORE mcore-*-*
2263 Fujitsu FRV architecture added by Red Hat frv*-*-*
2266 * New native configurations
2268 Alpha NetBSD alpha*-*-netbsd*
2269 SH NetBSD sh*-*-netbsdelf*
2270 MIPS NetBSD mips*-*-netbsd*
2271 UltraSPARC NetBSD sparc64-*-netbsd*
2273 * OBSOLETE configurations and files
2275 Configurations that have been declared obsolete in this release have
2276 been commented out. Unless there is activity to revive these
2277 configurations, the next release of GDB will have their sources
2278 permanently REMOVED.
2280 Mitsubishi D30V d30v-*-*
2281 OS/9000 i[34]86-*-os9k
2282 IBM AIX PS/2 i[3456]86-*-aix
2283 Fujitsu FR30 fr30-*-elf*
2284 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2285 Argonaut Risc Chip (ARC) arc-*-*
2286 i386 running Mach 3.0 i[3456]86-*-mach3*
2287 i386 running Mach i[3456]86-*-mach*
2288 i386 running OSF/1 i[3456]86-*osf1mk*
2289 HP/Apollo 68k Family m68*-apollo*-sysv*,
2291 m68*-hp-bsd*, m68*-hp-hpux*
2292 I960 with MON960 i960-*-coff
2294 * OBSOLETE languages
2296 CHILL, a Pascal like language used by telecommunications companies.
2298 * REMOVED configurations and files
2300 AMD 29k family via UDI a29k-amd-udi, udi29k
2301 A29K VxWorks a29k-*-vxworks
2302 AMD 29000 embedded, using EBMON a29k-none-none
2303 AMD 29000 embedded with COFF a29k-none-coff
2304 AMD 29000 embedded with a.out a29k-none-aout
2306 testsuite/gdb.hp/gdb.threads-hp/ directory
2308 * New command "set max-user-call-depth <nnn>"
2310 This command allows the user to limit the call depth of user-defined
2311 commands. The default is 1024.
2313 * Changes in FreeBSD/i386 native debugging.
2315 Support for the "generate-core-file" has been added.
2317 * New commands "dump", "append", and "restore".
2319 These commands allow data to be copied from target memory
2320 to a bfd-format or binary file (dump and append), and back
2321 from a file into memory (restore).
2323 * Improved "next/step" support on multi-processor Alpha Tru64.
2325 The previous single-step mechanism could cause unpredictable problems,
2326 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2327 of a software single-step mechanism prevents this.
2329 *** Changes in GDB 5.2.1:
2337 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2338 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2339 Fix, by Joel Brobecker imported from mainline.
2341 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2342 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2343 Fix, by Fred Fish, imported from mainline.
2345 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2346 Surprisingly enough, it works now.
2347 By Michal Ludvig, imported from mainline.
2349 i386 hardware watchpoint support:
2350 avoid misses on second run for some targets.
2351 By Pierre Muller, imported from mainline.
2353 *** Changes in GDB 5.2:
2355 * New command "set trust-readonly-sections on[off]".
2357 This command is a hint that tells gdb that read-only sections
2358 really are read-only (ie. that their contents will not change).
2359 In this mode, gdb will go to the object file rather than the
2360 target to read memory from read-only sections (such as ".text").
2361 This can be a significant performance improvement on some
2362 (notably embedded) targets.
2364 * New command "generate-core-file" (or "gcore").
2366 This new gdb command allows the user to drop a core file of the child
2367 process state at any time. So far it's been implemented only for
2368 GNU/Linux and Solaris, but should be relatively easily ported to other
2369 hosts. Argument is core file name (defaults to core.<pid>).
2371 * New command line option
2373 GDB now accepts --pid or -p followed by a process id.
2375 * Change in command line behavior -- corefiles vs. process ids.
2377 There is a subtle behavior in the way in which GDB handles
2378 command line arguments. The first non-flag argument is always
2379 a program to debug, but the second non-flag argument may either
2380 be a corefile or a process id. Previously, GDB would attempt to
2381 open the second argument as a corefile, and if that failed, would
2382 issue a superfluous error message and then attempt to attach it as
2383 a process. Now, if the second argument begins with a non-digit,
2384 it will be treated as a corefile. If it begins with a digit,
2385 GDB will attempt to attach it as a process, and if no such process
2386 is found, will then attempt to open it as a corefile.
2388 * Changes in ARM configurations.
2390 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2391 configuration is fully multi-arch.
2393 * New native configurations
2395 ARM NetBSD arm*-*-netbsd*
2396 x86 OpenBSD i[3456]86-*-openbsd*
2397 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2398 Sparc64 running FreeBSD sparc64-*-freebsd*
2402 Sanyo XStormy16 xstormy16-elf
2404 * OBSOLETE configurations and files
2406 Configurations that have been declared obsolete in this release have
2407 been commented out. Unless there is activity to revive these
2408 configurations, the next release of GDB will have their sources
2409 permanently REMOVED.
2411 AMD 29k family via UDI a29k-amd-udi, udi29k
2412 A29K VxWorks a29k-*-vxworks
2413 AMD 29000 embedded, using EBMON a29k-none-none
2414 AMD 29000 embedded with COFF a29k-none-coff
2415 AMD 29000 embedded with a.out a29k-none-aout
2417 testsuite/gdb.hp/gdb.threads-hp/ directory
2419 * REMOVED configurations and files
2421 TI TMS320C80 tic80-*-*
2423 PowerPC Solaris powerpcle-*-solaris*
2424 PowerPC Windows NT powerpcle-*-cygwin32
2425 PowerPC Netware powerpc-*-netware*
2426 Harris/CXUX m88k m88*-harris-cxux*
2427 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2428 ns32k-utek-sysv* ns32k-utek-*
2429 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2430 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2431 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2432 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2433 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2435 * Changes to command line processing
2437 The new `--args' feature can be used to specify command-line arguments
2438 for the inferior from gdb's command line.
2440 * Changes to key bindings
2442 There is a new `operate-and-get-next' function bound to `C-o'.
2444 *** Changes in GDB 5.1.1
2446 Fix compile problem on DJGPP.
2448 Fix a problem with floating-point registers on the i386 being
2451 Fix to stop GDB crashing on .debug_str debug info.
2453 Numerous documentation fixes.
2455 Numerous testsuite fixes.
2457 *** Changes in GDB 5.1:
2459 * New native configurations
2461 Alpha FreeBSD alpha*-*-freebsd*
2462 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2463 MIPS GNU/Linux mips*-*-linux*
2464 MIPS SGI Irix 6.x mips*-sgi-irix6*
2465 ia64 AIX ia64-*-aix*
2466 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2470 Motorola 68HC11 and 68HC12 m68hc11-elf
2472 UltraSparc running GNU/Linux sparc64-*-linux*
2474 * OBSOLETE configurations and files
2476 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2477 Harris/CXUX m88k m88*-harris-cxux*
2478 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2479 ns32k-utek-sysv* ns32k-utek-*
2480 TI TMS320C80 tic80-*-*
2482 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2483 PowerPC Solaris powerpcle-*-solaris*
2484 PowerPC Windows NT powerpcle-*-cygwin32
2485 PowerPC Netware powerpc-*-netware*
2486 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2487 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2488 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2489 Apple Macintosh (MPW) host N/A
2491 stuff.c (Program to stuff files into a specially prepared space in kdb)
2492 kdb-start.c (Main loop for the standalone kernel debugger)
2494 Configurations that have been declared obsolete in this release have
2495 been commented out. Unless there is activity to revive these
2496 configurations, the next release of GDB will have their sources
2497 permanently REMOVED.
2499 * REMOVED configurations and files
2501 Altos 3068 m68*-altos-*
2502 Convex c1-*-*, c2-*-*
2504 ARM RISCix arm-*-* (as host)
2508 * GDB has been converted to ISO C.
2510 GDB's source code has been converted to ISO C. In particular, the
2511 sources are fully protoized, and rely on standard headers being
2516 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2518 * The MI enabled by default.
2520 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2521 revised and enabled by default. Packages which use GDB as a debugging
2522 engine behind a UI or another front end are encouraged to switch to
2523 using the GDB/MI interface, instead of the old annotations interface
2524 which is now deprecated.
2526 * Support for debugging Pascal programs.
2528 GDB now includes support for debugging Pascal programs. The following
2529 main features are supported:
2531 - Pascal-specific data types such as sets;
2533 - automatic recognition of Pascal sources based on file-name
2536 - Pascal-style display of data types, variables, and functions;
2538 - a Pascal expression parser.
2540 However, some important features are not yet supported.
2542 - Pascal string operations are not supported at all;
2544 - there are some problems with boolean types;
2546 - Pascal type hexadecimal constants are not supported
2547 because they conflict with the internal variables format;
2549 - support for Pascal objects and classes is not full yet;
2551 - unlike Pascal, GDB is case-sensitive for symbol names.
2553 * Changes in completion.
2555 Commands such as `shell', `run' and `set args', which pass arguments
2556 to inferior programs, now complete on file names, similar to what
2557 users expect at the shell prompt.
2559 Commands which accept locations, such as `disassemble', `print',
2560 `breakpoint', `until', etc. now complete on filenames as well as
2561 program symbols. Thus, if you type "break foob TAB", and the source
2562 files linked into the programs include `foobar.c', that file name will
2563 be one of the candidates for completion. However, file names are not
2564 considered for completion after you typed a colon that delimits a file
2565 name from a name of a function in that file, as in "break foo.c:bar".
2567 `set demangle-style' completes on available demangling styles.
2569 * New platform-independent commands:
2571 It is now possible to define a post-hook for a command as well as a
2572 hook that runs before the command. For more details, see the
2573 documentation of `hookpost' in the GDB manual.
2575 * Changes in GNU/Linux native debugging.
2577 Support for debugging multi-threaded programs has been completely
2578 revised for all platforms except m68k and sparc. You can now debug as
2579 many threads as your system allows you to have.
2581 Attach/detach is supported for multi-threaded programs.
2583 Support for SSE registers was added for x86. This doesn't work for
2584 multi-threaded programs though.
2586 * Changes in MIPS configurations.
2588 Multi-arch support is enabled for all MIPS configurations.
2590 GDB can now be built as native debugger on SGI Irix 6.x systems for
2591 debugging n32 executables. (Debugging 64-bit executables is not yet
2594 * Unified support for hardware watchpoints in all x86 configurations.
2596 Most (if not all) native x86 configurations support hardware-assisted
2597 breakpoints and watchpoints in a unified manner. This support
2598 implements debug register sharing between watchpoints, which allows to
2599 put a virtually infinite number of watchpoints on the same address,
2600 and also supports watching regions up to 16 bytes with several debug
2603 The new maintenance command `maintenance show-debug-regs' toggles
2604 debugging print-outs in functions that insert, remove, and test
2605 watchpoints and hardware breakpoints.
2607 * Changes in the DJGPP native configuration.
2609 New command ``info dos sysinfo'' displays assorted information about
2610 the CPU, OS, memory, and DPMI server.
2612 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2613 display information about segment descriptors stored in GDT, LDT, and
2616 New commands ``info dos pde'' and ``info dos pte'' display entries
2617 from Page Directory and Page Tables (for now works with CWSDPMI only).
2618 New command ``info dos address-pte'' displays the Page Table entry for
2619 a given linear address.
2621 GDB can now pass command lines longer than 126 characters to the
2622 program being debugged (requires an update to the libdbg.a library
2623 which is part of the DJGPP development kit).
2625 DWARF2 debug info is now supported.
2627 It is now possible to `step' and `next' through calls to `longjmp'.
2629 * Changes in documentation.
2631 All GDB documentation was converted to GFDL, the GNU Free
2632 Documentation License.
2634 Tracepoints-related commands are now fully documented in the GDB
2637 TUI, the Text-mode User Interface, is now documented in the manual.
2639 Tracepoints-related commands are now fully documented in the GDB
2642 The "GDB Internals" manual now has an index. It also includes
2643 documentation of `ui_out' functions, GDB coding standards, x86
2644 hardware watchpoints, and memory region attributes.
2646 * GDB's version number moved to ``version.in''
2648 The Makefile variable VERSION has been replaced by the file
2649 ``version.in''. People creating GDB distributions should update the
2650 contents of this file.
2654 GUD support is now a standard part of the EMACS distribution.
2656 *** Changes in GDB 5.0:
2658 * Improved support for debugging FP programs on x86 targets
2660 Unified and much-improved support for debugging floating-point
2661 programs on all x86 targets. In particular, ``info float'' now
2662 displays the FP registers in the same format on all x86 targets, with
2663 greater level of detail.
2665 * Improvements and bugfixes in hardware-assisted watchpoints
2667 It is now possible to watch array elements, struct members, and
2668 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2669 on x86 targets no longer erroneously trigger when the address is
2672 * Improvements in the native DJGPP version of GDB
2674 The distribution now includes all the scripts and auxiliary files
2675 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2676 machines ``out of the box''.
2678 The DJGPP version can now debug programs that use signals. It is
2679 possible to catch signals that happened in the debuggee, deliver
2680 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2681 would kill the program being debugged.) Programs that hook hardware
2682 interrupts (keyboard, timer, etc.) can also be debugged.
2684 It is now possible to debug DJGPP programs that redirect their
2685 standard handles or switch them to raw (as opposed to cooked) mode, or
2686 even close them. The command ``run < foo > bar'' works as expected,
2687 and ``info terminal'' reports useful information about the debuggee's
2688 terminal, including raw/cooked mode, redirection, etc.
2690 The DJGPP version now uses termios functions for console I/O, which
2691 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2694 DOS-style file names with drive letters are now fully supported by
2697 It is now possible to debug DJGPP programs that switch their working
2698 directory. It is also possible to rerun the debuggee any number of
2699 times without restarting GDB; thus, you can use the same setup,
2700 breakpoints, etc. for many debugging sessions.
2702 * New native configurations
2704 ARM GNU/Linux arm*-*-linux*
2705 PowerPC GNU/Linux powerpc-*-linux*
2709 Motorola MCore mcore-*-*
2710 x86 VxWorks i[3456]86-*-vxworks*
2711 PowerPC VxWorks powerpc-*-vxworks*
2712 TI TMS320C80 tic80-*-*
2714 * OBSOLETE configurations
2716 Altos 3068 m68*-altos-*
2717 Convex c1-*-*, c2-*-*
2719 ARM RISCix arm-*-* (as host)
2722 Configurations that have been declared obsolete will be commented out,
2723 but the code will be left in place. If there is no activity to revive
2724 these configurations before the next release of GDB, the sources will
2725 be permanently REMOVED.
2727 * Gould support removed
2729 Support for the Gould PowerNode and NP1 has been removed.
2731 * New features for SVR4
2733 On SVR4 native platforms (such as Solaris), if you attach to a process
2734 without first loading a symbol file, GDB will now attempt to locate and
2735 load symbols from the running process's executable file.
2737 * Many C++ enhancements
2739 C++ support has been greatly improved. Overload resolution now works properly
2740 in almost all cases. RTTI support is on the way.
2742 * Remote targets can connect to a sub-program
2744 A popen(3) style serial-device has been added. This device starts a
2745 sub-process (such as a stand-alone simulator) and then communicates
2746 with that. The sub-program to run is specified using the syntax
2747 ``|<program> <args>'' vis:
2749 (gdb) set remotedebug 1
2750 (gdb) target extended-remote |mn10300-elf-sim program-args
2752 * MIPS 64 remote protocol
2754 A long standing bug in the mips64 remote protocol where by GDB
2755 expected certain 32 bit registers (ex SR) to be transfered as 32
2756 instead of 64 bits has been fixed.
2758 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2759 added to provide backward compatibility with older versions of GDB.
2761 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2763 The command ``set remotebinarydownload'' command has been replaced by
2764 ``set remote X-packet''. Other commands in ``set remote'' family
2765 include ``set remote P-packet''.
2767 * Breakpoint commands accept ranges.
2769 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2770 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2771 ``tracepoint passcount'' also accepts a range of tracepoints.
2773 * ``apropos'' command added.
2775 The ``apropos'' command searches through command names and
2776 documentation strings, printing out matches, making it much easier to
2777 try to find a command that does what you are looking for.
2781 A new machine oriented interface (MI) has been added to GDB. This
2782 interface is designed for debug environments running GDB as a separate
2783 process. This is part of the long term libGDB project. See the
2784 "GDB/MI" chapter of the GDB manual for further information. It can be
2785 enabled by configuring with:
2787 .../configure --enable-gdbmi
2789 *** Changes in GDB-4.18:
2791 * New native configurations
2793 HP-UX 10.20 hppa*-*-hpux10.20
2794 HP-UX 11.x hppa*-*-hpux11.0*
2795 M68K GNU/Linux m68*-*-linux*
2799 Fujitsu FR30 fr30-*-elf*
2800 Intel StrongARM strongarm-*-*
2801 Mitsubishi D30V d30v-*-*
2803 * OBSOLETE configurations
2805 Gould PowerNode, NP1 np1-*-*, pn-*-*
2807 Configurations that have been declared obsolete will be commented out,
2808 but the code will be left in place. If there is no activity to revive
2809 these configurations before the next release of GDB, the sources will
2810 be permanently REMOVED.
2814 As a compatibility experiment, GDB's source files buildsym.h and
2815 buildsym.c have been converted to pure standard C, no longer
2816 containing any K&R compatibility code. We believe that all systems in
2817 use today either come with a standard C compiler, or have a GCC port
2818 available. If this is not true, please report the affected
2819 configuration to bug-gdb@gnu.org immediately. See the README file for
2820 information about getting a standard C compiler if you don't have one
2825 GDB now uses readline 2.2.
2827 * set extension-language
2829 You can now control the mapping between filename extensions and source
2830 languages by using the `set extension-language' command. For instance,
2831 you can ask GDB to treat .c files as C++ by saying
2832 set extension-language .c c++
2833 The command `info extensions' lists all of the recognized extensions
2834 and their associated languages.
2836 * Setting processor type for PowerPC and RS/6000
2838 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2839 you can use the `set processor' command to specify what variant of the
2840 PowerPC family you are debugging. The command
2844 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2845 following PowerPC and RS6000 variants:
2847 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2848 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2850 403GC IBM PowerPC 403GC
2851 505 Motorola PowerPC 505
2852 860 Motorola PowerPC 860 or 850
2853 601 Motorola PowerPC 601
2854 602 Motorola PowerPC 602
2855 603 Motorola/IBM PowerPC 603 or 603e
2856 604 Motorola PowerPC 604 or 604e
2857 750 Motorola/IBM PowerPC 750 or 750
2859 At the moment, this command just tells GDB what to name the
2860 special-purpose processor registers. Since almost all the affected
2861 registers are inaccessible to user-level programs, this command is
2862 only useful for remote debugging in its present form.
2866 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2867 more extensive support for HP-UX. Added features include shared
2868 library support, kernel threads and hardware watchpoints for 11.00,
2869 support for HP's ANSI C and C++ compilers, and a compatibility mode
2870 for xdb and dbx commands.
2874 HP's donation includes the new concept of catchpoints, which is a
2875 generalization of the old catch command. On HP-UX, it is now possible
2876 to catch exec, fork, and vfork, as well as library loading.
2878 This means that the existing catch command has changed; its first
2879 argument now specifies the type of catch to be set up. See the
2880 output of "help catch" for a list of catchpoint types.
2882 * Debugging across forks
2884 On HP-UX, you can choose which process to debug when a fork() happens
2889 HP has donated a curses-based terminal user interface (TUI). To get
2890 it, build with --enable-tui. Although this can be enabled for any
2891 configuration, at present it only works for native HP debugging.
2893 * GDB remote protocol additions
2895 A new protocol packet 'X' that writes binary data is now available.
2896 Default behavior is to try 'X', then drop back to 'M' if the stub
2897 fails to respond. The settable variable `remotebinarydownload'
2898 allows explicit control over the use of 'X'.
2900 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2901 full 64-bit address. The command
2903 set remoteaddresssize 32
2905 can be used to revert to the old behaviour. For existing remote stubs
2906 the change should not be noticed, as the additional address information
2909 In order to assist in debugging stubs, you may use the maintenance
2910 command `packet' to send any text string to the stub. For instance,
2912 maint packet heythere
2914 sends the packet "$heythere#<checksum>". Note that it is very easy to
2915 disrupt a debugging session by sending the wrong packet at the wrong
2918 The compare-sections command allows you to compare section data on the
2919 target to what is in the executable file without uploading or
2920 downloading, by comparing CRC checksums.
2922 * Tracing can collect general expressions
2924 You may now collect general expressions at tracepoints. This requires
2925 further additions to the target-side stub; see tracepoint.c and
2926 doc/agentexpr.texi for further details.
2928 * mask-address variable for Mips
2930 For Mips targets, you may control the zeroing of the upper 32 bits of
2931 a 64-bit address by entering `set mask-address on'. This is mainly
2932 of interest to users of embedded R4xxx and R5xxx processors.
2934 * Higher serial baud rates
2936 GDB's serial code now allows you to specify baud rates 57600, 115200,
2937 230400, and 460800 baud. (Note that your host system may not be able
2938 to achieve all of these rates.)
2942 The i960 configuration now includes an initial implementation of a
2943 builtin simulator, contributed by Jim Wilson.
2946 *** Changes in GDB-4.17:
2948 * New native configurations
2950 Alpha GNU/Linux alpha*-*-linux*
2951 Unixware 2.x i[3456]86-unixware2*
2952 Irix 6.x mips*-sgi-irix6*
2953 PowerPC GNU/Linux powerpc-*-linux*
2954 PowerPC Solaris powerpcle-*-solaris*
2955 Sparc GNU/Linux sparc-*-linux*
2956 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2960 Argonaut Risc Chip (ARC) arc-*-*
2961 Hitachi H8/300S h8300*-*-*
2962 Matsushita MN10200 w/simulator mn10200-*-*
2963 Matsushita MN10300 w/simulator mn10300-*-*
2964 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2965 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2966 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2967 Mitsubishi D10V w/simulator d10v-*-*
2968 Mitsubishi M32R/D w/simulator m32r-*-elf*
2969 Tsqware Sparclet sparclet-*-*
2970 NEC V850 w/simulator v850-*-*
2972 * New debugging protocols
2974 ARM with RDI protocol arm*-*-*
2975 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2976 DDB and LSI variants of PMON protocol mips*-*-*
2977 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2978 PowerPC with SDS protocol powerpc{,le}-*-eabi
2979 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2983 All configurations can now understand and use the DWARF 2 debugging
2984 format. The choice is automatic, if the symbol file contains DWARF 2
2989 GDB now includes basic Java language support. This support is
2990 only useful with Java compilers that produce native machine code.
2992 * solib-absolute-prefix and solib-search-path
2994 For SunOS and SVR4 shared libraries, you may now set the prefix for
2995 loading absolute shared library symbol files, and the search path for
2996 locating non-absolute shared library symbol files.
2998 * Live range splitting
3000 GDB can now effectively debug code for which GCC has performed live
3001 range splitting as part of its optimization. See gdb/doc/LRS for
3002 more details on the expected format of the stabs information.
3006 GDB's support for the GNU Hurd, including thread debugging, has been
3007 updated to work with current versions of the Hurd.
3011 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3012 instruction set. ARM GDB automatically detects when Thumb
3013 instructions are in use, and adjusts disassembly and backtracing
3018 GDB's MIPS target configurations now handle the MIP16 16-bit
3023 GDB now includes support for overlays; if an executable has been
3024 linked such that multiple sections are based at the same address, GDB
3025 will decide which section to use for symbolic info. You can choose to
3026 control the decision manually, using overlay commands, or implement
3027 additional target-side support and use "overlay load-target" to bring
3028 in the overlay mapping. Do "help overlay" for more detail.
3032 The command "info symbol <address>" displays information about
3033 the symbol at the specified address.
3037 The standard remote protocol now includes an extension that allows
3038 asynchronous collection and display of trace data. This requires
3039 extensive support in the target-side debugging stub. Tracing mode
3040 includes a new interaction mode in GDB and new commands: see the
3041 file tracepoint.c for more details.
3045 Configurations for embedded MIPS now include a simulator contributed
3046 by Cygnus Solutions. The simulator supports the instruction sets
3047 of most MIPS variants.
3051 Sparc configurations may now include the ERC32 simulator contributed
3052 by the European Space Agency. The simulator is not built into
3053 Sparc targets by default; configure with --enable-sim to include it.
3057 For target configurations that may include multiple variants of a
3058 basic architecture (such as MIPS and SH), you may now set the
3059 architecture explicitly. "set arch" sets, "info arch" lists
3060 the possible architectures.
3062 *** Changes in GDB-4.16:
3064 * New native configurations
3066 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3067 M68K NetBSD m68k-*-netbsd*
3068 PowerPC AIX 4.x powerpc-*-aix*
3069 PowerPC MacOS powerpc-*-macos*
3070 PowerPC Windows NT powerpcle-*-cygwin32
3071 RS/6000 AIX 4.x rs6000-*-aix4*
3075 ARM with RDP protocol arm-*-*
3076 I960 with MON960 i960-*-coff
3077 MIPS VxWorks mips*-*-vxworks*
3078 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3079 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3081 Matra Sparclet sparclet-*-*
3085 The powerpc-eabi configuration now includes the PSIM simulator,
3086 contributed by Andrew Cagney, with assistance from Mike Meissner.
3087 PSIM is a very elaborate model of the PowerPC, including not only
3088 basic instruction set execution, but also details of execution unit
3089 performance and I/O hardware. See sim/ppc/README for more details.
3093 GDB now works with Solaris 2.5.
3095 * Windows 95/NT native
3097 GDB will now work as a native debugger on Windows 95 and Windows NT.
3098 To build it from source, you must use the "gnu-win32" environment,
3099 which uses a DLL to emulate enough of Unix to run the GNU tools.
3100 Further information, binaries, and sources are available at
3101 ftp.cygnus.com, under pub/gnu-win32.
3103 * dont-repeat command
3105 If a user-defined command includes the command `dont-repeat', then the
3106 command will not be repeated if the user just types return. This is
3107 useful if the command is time-consuming to run, so that accidental
3108 extra keystrokes don't run the same command many times.
3110 * Send break instead of ^C
3112 The standard remote protocol now includes an option to send a break
3113 rather than a ^C to the target in order to interrupt it. By default,
3114 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3116 * Remote protocol timeout
3118 The standard remote protocol includes a new variable `remotetimeout'
3119 that allows you to set the number of seconds before GDB gives up trying
3120 to read from the target. The default value is 2.
3122 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3124 By default GDB will automatically keep track of objects as they are
3125 loaded and unloaded by the dynamic linker. By using the command `set
3126 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3127 when shared library events occur, thus allowing you to set breakpoints
3128 in shared libraries which are explicitly loaded by the inferior.
3130 Note this feature does not work on hpux8. On hpux9 you must link
3131 /usr/lib/end.o into your program. This feature should work
3132 automatically on hpux10.
3134 * Irix 5.x hardware watchpoint support
3136 Irix 5 configurations now support the use of hardware watchpoints.
3138 * Mips protocol "SYN garbage limit"
3140 When debugging a Mips target using the `target mips' protocol, you
3141 may set the number of characters that GDB will ignore by setting
3142 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3143 every character. The default value is 1050.
3145 * Recording and replaying remote debug sessions
3147 If you set `remotelogfile' to the name of a file, gdb will write to it
3148 a recording of a remote debug session. This recording may then be
3149 replayed back to gdb using "gdbreplay". See gdbserver/README for
3150 details. This is useful when you have a problem with GDB while doing
3151 remote debugging; you can make a recording of the session and send it
3152 to someone else, who can then recreate the problem.
3154 * Speedups for remote debugging
3156 GDB includes speedups for downloading and stepping MIPS systems using
3157 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3158 and more efficient S-record downloading.
3160 * Memory use reductions and statistics collection
3162 GDB now uses less memory and reports statistics about memory usage.
3163 Try the `maint print statistics' command, for example.
3165 *** Changes in GDB-4.15:
3167 * Psymtabs for XCOFF
3169 The symbol reader for AIX GDB now uses partial symbol tables. This
3170 can greatly improve startup time, especially for large executables.
3172 * Remote targets use caching
3174 Remote targets now use a data cache to speed up communication with the
3175 remote side. The data cache could lead to incorrect results because
3176 it doesn't know about volatile variables, thus making it impossible to
3177 debug targets which use memory mapped I/O devices. `set remotecache
3178 off' turns the the data cache off.
3180 * Remote targets may have threads
3182 The standard remote protocol now includes support for multiple threads
3183 in the target system, using new protocol commands 'H' and 'T'. See
3184 gdb/remote.c for details.
3188 If GDB is configured with `--enable-netrom', then it will include
3189 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3190 acts as though it is a bank of ROM on the target board, but you can
3191 write into it over the network. GDB's support consists only of
3192 support for fast loading into the emulated ROM; to debug, you must use
3193 another protocol, such as standard remote protocol. The usual
3194 sequence is something like
3196 target nrom <netrom-hostname>
3198 target remote <netrom-hostname>:1235
3202 GDB now includes support for the Apple Macintosh, as a host only. It
3203 may be run as either an MPW tool or as a standalone application, and
3204 it can debug through the serial port. All the usual GDB commands are
3205 available, but to the target command, you must supply "serial" as the
3206 device type instead of "/dev/ttyXX". See mpw-README in the main
3207 directory for more information on how to build. The MPW configuration
3208 scripts */mpw-config.in support only a few targets, and only the
3209 mips-idt-ecoff target has been tested.
3213 GDB configuration now uses autoconf. This is not user-visible,
3214 but does simplify configuration and building.
3218 GDB now supports hpux10.
3220 *** Changes in GDB-4.14:
3222 * New native configurations
3224 x86 FreeBSD i[345]86-*-freebsd
3225 x86 NetBSD i[345]86-*-netbsd
3226 NS32k NetBSD ns32k-*-netbsd
3227 Sparc NetBSD sparc-*-netbsd
3231 A29K VxWorks a29k-*-vxworks
3232 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3233 CPU32 EST-300 emulator m68*-*-est*
3234 PowerPC ELF powerpc-*-elf
3237 * Alpha OSF/1 support for procfs
3239 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3240 possible to attach to running processes. As the mounting of the /proc
3241 filesystem is optional on the Alpha, GDB automatically determines
3242 the availability of /proc during startup. This can lead to problems
3243 if /proc is unmounted after GDB has been started.
3245 * Arguments to user-defined commands
3247 User commands may accept up to 10 arguments separated by whitespace.
3248 Arguments are accessed within the user command via $arg0..$arg9. A
3251 print $arg0 + $arg1 + $arg2
3253 To execute the command use:
3256 Defines the command "adder" which prints the sum of its three arguments.
3257 Note the arguments are text substitutions, so they may reference variables,
3258 use complex expressions, or even perform inferior function calls.
3260 * New `if' and `while' commands
3262 This makes it possible to write more sophisticated user-defined
3263 commands. Both commands take a single argument, which is the
3264 expression to evaluate, and must be followed by the commands to
3265 execute, one per line, if the expression is nonzero, the list being
3266 terminated by the word `end'. The `if' command list may include an
3267 `else' word, which causes the following commands to be executed only
3268 if the expression is zero.
3270 * Fortran source language mode
3272 GDB now includes partial support for Fortran 77. It will recognize
3273 Fortran programs and can evaluate a subset of Fortran expressions, but
3274 variables and functions may not be handled correctly. GDB will work
3275 with G77, but does not yet know much about symbols emitted by other
3278 * Better HPUX support
3280 Most debugging facilities now work on dynamic executables for HPPAs
3281 running hpux9 or later. You can attach to running dynamically linked
3282 processes, but by default the dynamic libraries will be read-only, so
3283 for instance you won't be able to put breakpoints in them. To change
3284 that behavior do the following before running the program:
3290 This will cause the libraries to be mapped private and read-write.
3291 To revert to the normal behavior, do this:
3297 You cannot set breakpoints or examine data in the library until after
3298 the library is loaded if the function/data symbols do not have
3301 GDB can now also read debug symbols produced by the HP C compiler on
3302 HPPAs (sorry, no C++, Fortran or 68k support).
3304 * Target byte order now dynamically selectable
3306 You can choose which byte order to use with a target system, via the
3307 commands "set endian big" and "set endian little", and you can see the
3308 current setting by using "show endian". You can also give the command
3309 "set endian auto", in which case GDB will use the byte order
3310 associated with the executable. Currently, only embedded MIPS
3311 configurations support dynamic selection of target byte order.
3313 * New DOS host serial code
3315 This version uses DPMI interrupts to handle buffered I/O, so you
3316 no longer need to run asynctsr when debugging boards connected to
3319 *** Changes in GDB-4.13:
3321 * New "complete" command
3323 This lists all the possible completions for the rest of the line, if it
3324 were to be given as a command itself. This is intended for use by emacs.
3326 * Trailing space optional in prompt
3328 "set prompt" no longer adds a space for you after the prompt you set. This
3329 allows you to set a prompt which ends in a space or one that does not.
3331 * Breakpoint hit counts
3333 "info break" now displays a count of the number of times the breakpoint
3334 has been hit. This is especially useful in conjunction with "ignore"; you
3335 can ignore a large number of breakpoint hits, look at the breakpoint info
3336 to see how many times the breakpoint was hit, then run again, ignoring one
3337 less than that number, and this will get you quickly to the last hit of
3340 * Ability to stop printing at NULL character
3342 "set print null-stop" will cause GDB to stop printing the characters of
3343 an array when the first NULL is encountered. This is useful when large
3344 arrays actually contain only short strings.
3346 * Shared library breakpoints
3348 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3349 breakpoints in shared libraries before the executable is run.
3351 * Hardware watchpoints
3353 There is a new hardware breakpoint for the watch command for sparclite
3354 targets. See gdb/sparclite/hw_breakpoint.note.
3356 Hardware watchpoints are also now supported under GNU/Linux.
3360 Annotations have been added. These are for use with graphical interfaces,
3361 and are still experimental. Currently only gdba.el uses these.
3363 * Improved Irix 5 support
3365 GDB now works properly with Irix 5.2.
3367 * Improved HPPA support
3369 GDB now works properly with the latest GCC and GAS.
3371 * New native configurations
3373 Sequent PTX4 i[34]86-sequent-ptx4
3374 HPPA running OSF/1 hppa*-*-osf*
3375 Atari TT running SVR4 m68*-*-sysv4*
3376 RS/6000 LynxOS rs6000-*-lynxos*
3380 OS/9000 i[34]86-*-os9k
3381 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3384 * Hitachi SH7000 and E7000-PC ICE support
3386 There is now support for communicating with the Hitachi E7000-PC ICE.
3387 This is available automatically when GDB is configured for the SH.
3391 As usual, a variety of small fixes and improvements, both generic
3392 and configuration-specific. See the ChangeLog for more detail.
3394 *** Changes in GDB-4.12:
3396 * Irix 5 is now supported
3400 GDB-4.12 on the HPPA has a number of changes which make it unable
3401 to debug the output from the currently released versions of GCC and
3402 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3403 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3404 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3407 *** Changes in GDB-4.11:
3409 * User visible changes:
3413 The "set remotedebug" option is now consistent between the mips remote
3414 target, remote targets using the gdb-specific protocol, UDI (AMD's
3415 debug protocol for the 29k) and the 88k bug monitor. It is now an
3416 integer specifying a debug level (normally 0 or 1, but 2 means more
3417 debugging info for the mips target).
3419 * DEC Alpha native support
3421 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3422 debug info, but GDB works fairly well with the DEC compiler and should
3423 work with a future GCC release. See the README file for a few
3424 Alpha-specific notes.
3426 * Preliminary thread implementation
3428 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3430 * LynxOS native and target support for 386
3432 This release has been hosted on LynxOS 2.2, and also can be configured
3433 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3436 * Improvements in C++ mangling/demangling.
3438 This release has much better g++ debugging, specifically in name
3439 mangling/demangling, virtual function calls, print virtual table,
3440 call methods, ...etc.
3442 *** Changes in GDB-4.10:
3444 * User visible changes:
3446 Remote debugging using the GDB-specific (`target remote') protocol now
3447 supports the `load' command. This is only useful if you have some
3448 other way of getting the stub to the target system, and you can put it
3449 somewhere in memory where it won't get clobbered by the download.
3451 Filename completion now works.
3453 When run under emacs mode, the "info line" command now causes the
3454 arrow to point to the line specified. Also, "info line" prints
3455 addresses in symbolic form (as well as hex).
3457 All vxworks based targets now support a user settable option, called
3458 vxworks-timeout. This option represents the number of seconds gdb
3459 should wait for responses to rpc's. You might want to use this if
3460 your vxworks target is, perhaps, a slow software simulator or happens
3461 to be on the far side of a thin network line.
3465 This release contains support for using a DEC alpha as a GDB host for
3466 cross debugging. Native alpha debugging is not supported yet.
3469 *** Changes in GDB-4.9:
3473 This is the first GDB release which is accompanied by a matching testsuite.
3474 The testsuite requires installation of dejagnu, which should be available
3475 via ftp from most sites that carry GNU software.
3479 'Cfront' style demangling has had its name changed to 'ARM' style, to
3480 emphasize that it was written from the specifications in the C++ Annotated
3481 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3482 disclaimers, it still generated too much confusion with users attempting to
3483 use gdb with AT&T cfront.
3487 GDB now uses a standard remote interface to a simulator library.
3488 So far, the library contains simulators for the Zilog Z8001/2, the
3489 Hitachi H8/300, H8/500 and Super-H.
3491 * New targets supported
3493 H8/300 simulator h8300-hitachi-hms or h8300hms
3494 H8/500 simulator h8500-hitachi-hms or h8500hms
3495 SH simulator sh-hitachi-hms or sh
3496 Z8000 simulator z8k-zilog-none or z8ksim
3497 IDT MIPS board over serial line mips-idt-ecoff
3499 Cross-debugging to GO32 targets is supported. It requires a custom
3500 version of the i386-stub.c module which is integrated with the
3501 GO32 memory extender.
3503 * New remote protocols
3505 MIPS remote debugging protocol.
3507 * New source languages supported
3509 This version includes preliminary support for Chill, a Pascal like language
3510 used by telecommunications companies. Chill support is also being integrated
3511 into the GNU compiler, but we don't know when it will be publically available.
3514 *** Changes in GDB-4.8:
3516 * HP Precision Architecture supported
3518 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3519 version of this support was available as a set of patches from the
3520 University of Utah. GDB does not support debugging of programs
3521 compiled with the HP compiler, because HP will not document their file
3522 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3523 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3525 Many problems in the preliminary version have been fixed.
3527 * Faster and better demangling
3529 We have improved template demangling and fixed numerous bugs in the GNU style
3530 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3531 character types (wchar_t) are now supported. Demangling of each symbol is now
3532 only done once, and is cached when the symbol table for a file is read in.
3533 This results in a small increase in memory usage for C programs, a moderate
3534 increase in memory usage for C++ programs, and a fantastic speedup in
3537 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3538 from the specifications in the Annotated Reference Manual, which AT&T's
3539 compiler does not actually implement.
3541 * G++ multiple inheritance compiler problem
3543 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3544 inheritance lattices was reworked to properly discover ambiguities. We
3545 recently found an example which causes this new algorithm to fail in a
3546 very subtle way, producing bad debug information for those classes.
3547 The file 'gcc.patch' (in this directory) can be applied to gcc to
3548 circumvent the problem. A future GCC release will contain a complete
3551 The previous G++ debug info problem (mentioned below for the gdb-4.7
3552 release) is fixed in gcc version 2.3.2.
3554 * Improved configure script
3556 The `configure' script will now attempt to guess your system type if
3557 you don't supply a host system type. The old scheme of supplying a
3558 host system triplet is preferable over using this. All the magic is
3559 done in the new `config.guess' script. Examine it for details.
3561 We have also brought our configure script much more in line with the FSF's
3562 version. It now supports the --with-xxx options. In particular,
3563 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3564 The resulting GDB will not be able to read arbitrary object file formats --
3565 only the format ``expected'' to be used on the configured target system.
3566 We hope to make this the default in a future release.
3568 * Documentation improvements
3570 There's new internal documentation on how to modify GDB, and how to
3571 produce clean changes to the code. We implore people to read it
3572 before submitting changes.
3574 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3575 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3576 `info' files are also provided. To build `info' files from scratch,
3577 you will need the latest `makeinfo' release, which will be available in
3578 a future texinfo-X.Y release.
3580 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3581 We're not sure exactly which versions have this problem, but it has
3582 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3583 or better. If that isn't possible, there is a patch in
3584 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3585 around this problem.
3589 GDB now supports array constants that can be used in expressions typed in by
3590 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3591 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3594 The new directory `gdb/sparclite' contains a program that demonstrates
3595 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3597 * New native hosts supported
3599 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3600 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3602 * New targets supported
3604 AMD 29k family via UDI a29k-amd-udi or udi29k
3606 * New file formats supported
3608 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3609 HPUX core files, and SCO 3.2v2 core files.
3613 Attaching to processes now works again; thanks for the many bug reports.
3615 We have also stomped on a bunch of core dumps caused by
3616 printf_filtered("%s") problems.
3618 We eliminated a copyright problem on the rpc and ptrace header files
3619 for VxWorks, which was discovered at the last minute during the 4.7
3620 release. You should now be able to build a VxWorks GDB.
3622 You can now interrupt gdb while an attached process is running. This
3623 will cause the attached process to stop, and give control back to GDB.
3625 We fixed problems caused by using too many file descriptors
3626 for reading symbols from object files and libraries. This was
3627 especially a problem for programs that used many (~100) shared
3630 The `step' command now only enters a subroutine if there is line number
3631 information for the subroutine. Otherwise it acts like the `next'
3632 command. Previously, `step' would enter subroutines if there was
3633 any debugging information about the routine. This avoids problems
3634 when using `cc -g1' on MIPS machines.
3636 * Internal improvements
3638 GDB's internal interfaces have been improved to make it easier to support
3639 debugging of multiple languages in the future.
3641 GDB now uses a common structure for symbol information internally.
3642 Minimal symbols (derived from linkage symbols in object files), partial
3643 symbols (from a quick scan of debug information), and full symbols
3644 contain a common subset of information, making it easier to write
3645 shared code that handles any of them.
3647 * New command line options
3649 We now accept --silent as an alias for --quiet.
3653 The memory-mapped-malloc library is now licensed under the GNU Library
3654 General Public License.
3656 *** Changes in GDB-4.7:
3658 * Host/native/target split
3660 GDB has had some major internal surgery to untangle the support for
3661 hosts and remote targets. Now, when you configure GDB for a remote
3662 target, it will no longer load in all of the support for debugging
3663 local programs on the host. When fully completed and tested, this will
3664 ensure that arbitrary host/target combinations are possible.
3666 The primary conceptual shift is to separate the non-portable code in
3667 GDB into three categories. Host specific code is required any time GDB
3668 is compiled on that host, regardless of the target. Target specific
3669 code relates to the peculiarities of the target, but can be compiled on
3670 any host. Native specific code is everything else: it can only be
3671 built when the host and target are the same system. Child process
3672 handling and core file support are two common `native' examples.
3674 GDB's use of /proc for controlling Unix child processes is now cleaner.
3675 It has been split out into a single module under the `target_ops' vector,
3676 plus two native-dependent functions for each system that uses /proc.
3678 * New hosts supported
3680 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3681 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3682 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3684 * New targets supported
3686 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3687 68030 and CPU32 m68030-*-*, m68332-*-*
3689 * New native hosts supported
3691 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3692 (386bsd is not well tested yet)
3693 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3695 * New file formats supported
3697 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3698 supports reading of `a.out.adobe' object files, which are an a.out
3699 format extended with minimal information about multiple sections.
3703 `show copying' is the same as the old `info copying'.
3704 `show warranty' is the same as `info warrantee'.
3705 These were renamed for consistency. The old commands continue to work.
3707 `info handle' is a new alias for `info signals'.
3709 You can now define pre-command hooks, which attach arbitrary command
3710 scripts to any command. The commands in the hook will be executed
3711 prior to the user's command. You can also create a hook which will be
3712 executed whenever the program stops. See gdb.texinfo.
3716 We now deal with Cfront style name mangling, and can even extract type
3717 info from mangled symbols. GDB can automatically figure out which
3718 symbol mangling style your C++ compiler uses.
3720 Calling of methods and virtual functions has been improved as well.
3724 The crash that occured when debugging Sun Ansi-C compiled binaries is
3725 fixed. This was due to mishandling of the extra N_SO stabs output
3728 We also finally got Ultrix 4.2 running in house, and fixed core file
3729 support, with help from a dozen people on the net.
3731 John M. Farrell discovered that the reason that single-stepping was so
3732 slow on all of the Mips based platforms (primarily SGI and DEC) was
3733 that we were trying to demangle and lookup a symbol used for internal
3734 purposes on every instruction that was being stepped through. Changing
3735 the name of that symbol so that it couldn't be mistaken for a C++
3736 mangled symbol sped things up a great deal.
3738 Rich Pixley sped up symbol lookups in general by getting much smarter
3739 about when C++ symbol mangling is necessary. This should make symbol
3740 completion (TAB on the command line) much faster. It's not as fast as
3741 we'd like, but it's significantly faster than gdb-4.6.
3745 A new user controllable variable 'call_scratch_address' can
3746 specify the location of a scratch area to be used when GDB
3747 calls a function in the target. This is necessary because the
3748 usual method of putting the scratch area on the stack does not work
3749 in systems that have separate instruction and data spaces.
3751 We integrated changes to support the 29k UDI (Universal Debugger
3752 Interface), but discovered at the last minute that we didn't have all
3753 of the appropriate copyright paperwork. We are working with AMD to
3754 resolve this, and hope to have it available soon.
3758 We have sped up the remote serial line protocol, especially for targets
3759 with lots of registers. It now supports a new `expedited status' ('T')
3760 message which can be used in place of the existing 'S' status message.
3761 This allows the remote stub to send only the registers that GDB
3762 needs to make a quick decision about single-stepping or conditional
3763 breakpoints, eliminating the need to fetch the entire register set for
3764 each instruction being stepped through.
3766 The GDB remote serial protocol now implements a write-through cache for
3767 registers, only re-reading the registers if the target has run.
3769 There is also a new remote serial stub for SPARC processors. You can
3770 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3771 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3772 processor with a serial port.
3776 Configure.in files have become much easier to read and modify. A new
3777 `table driven' format makes it more obvious what configurations are
3778 supported, and what files each one uses.
3782 There is a new opcodes library which will eventually contain all of the
3783 disassembly routines and opcode tables. At present, it only contains
3784 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3785 disassembler (binutils/objdump) to share these routines.
3787 The libiberty library is now copylefted under the GNU Library General
3788 Public License. This allows more liberal use, and was done so libg++
3789 can use it. This makes no difference to GDB, since the Library License
3790 grants all the rights from the General Public License.
3794 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3795 reference to the stabs symbol info used by the debugger. It is (as far
3796 as we know) the only published document on this fascinating topic. We
3797 encourage you to read it, compare it to the stabs information on your
3798 system, and send improvements on the document in general (to
3799 bug-gdb@prep.ai.mit.edu).
3801 And, of course, many bugs have been fixed.
3804 *** Changes in GDB-4.6:
3806 * Better support for C++ function names
3808 GDB now accepts as input the "demangled form" of C++ overloaded function
3809 names and member function names, and can do command completion on such names
3810 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3811 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3812 Make use of command completion, it is your friend.
3814 GDB also now accepts a variety of C++ mangled symbol formats. They are
3815 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3816 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3817 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3818 for the list of formats.
3820 * G++ symbol mangling problem
3822 Recent versions of gcc have a bug in how they emit debugging information for
3823 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3824 directory) can be applied to gcc to fix the problem. Alternatively, if you
3825 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3826 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3827 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3830 * New 'maintenance' command
3832 All of the commands related to hacking GDB internals have been moved out of
3833 the main command set, and now live behind the 'maintenance' command. This
3834 can also be abbreviated as 'mt'. The following changes were made:
3836 dump-me -> maintenance dump-me
3837 info all-breakpoints -> maintenance info breakpoints
3838 printmsyms -> maintenance print msyms
3839 printobjfiles -> maintenance print objfiles
3840 printpsyms -> maintenance print psymbols
3841 printsyms -> maintenance print symbols
3843 The following commands are new:
3845 maintenance demangle Call internal GDB demangler routine to
3846 demangle a C++ link name and prints the result.
3847 maintenance print type Print a type chain for a given symbol
3849 * Change to .gdbinit file processing
3851 We now read the $HOME/.gdbinit file before processing the argv arguments
3852 (e.g. reading symbol files or core files). This allows global parameters to
3853 be set, which will apply during the symbol reading. The ./.gdbinit is still
3854 read after argv processing.
3856 * New hosts supported
3858 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3860 GNU/Linux support i386-unknown-linux or linux
3862 We are also including code to support the HP/PA running BSD and HPUX. This
3863 is almost guaranteed not to work, as we didn't have time to test or build it
3864 for this release. We are including it so that the more adventurous (or
3865 masochistic) of you can play with it. We also had major problems with the
3866 fact that the compiler that we got from HP doesn't support the -g option.
3869 * New targets supported
3871 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3873 * More smarts about finding #include files
3875 GDB now remembers the compilation directory for all include files, and for
3876 all files from which C is generated (like yacc and lex sources). This
3877 greatly improves GDB's ability to find yacc/lex sources, and include files,
3878 especially if you are debugging your program from a directory different from
3879 the one that contains your sources.
3881 We also fixed a bug which caused difficulty with listing and setting
3882 breakpoints in include files which contain C code. (In the past, you had to
3883 try twice in order to list an include file that you hadn't looked at before.)
3885 * Interesting infernals change
3887 GDB now deals with arbitrary numbers of sections, where the symbols for each
3888 section must be relocated relative to that section's landing place in the
3889 target's address space. This work was needed to support ELF with embedded
3890 stabs used by Solaris-2.0.
3892 * Bug fixes (of course!)
3894 There have been loads of fixes for the following things:
3895 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3896 i960, stabs, DOS(GO32), procfs, etc...
3898 See the ChangeLog for details.
3900 *** Changes in GDB-4.5:
3902 * New machines supported (host and target)
3904 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3906 SGI Irix-4.x mips-sgi-irix4 or iris4
3908 * New malloc package
3910 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3911 Mmalloc is capable of handling mutiple heaps of memory. It is also
3912 capable of saving a heap to a file, and then mapping it back in later.
3913 This can be used to greatly speedup the startup of GDB by using a
3914 pre-parsed symbol table which lives in a mmalloc managed heap. For
3915 more details, please read mmalloc/mmalloc.texi.
3919 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3920 'help info proc' for details.
3922 * MIPS ecoff symbol table format
3924 The code that reads MIPS symbol table format is now supported on all hosts.
3925 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3928 * File name changes for MS-DOS
3930 Many files in the config directories have been renamed to make it easier to
3931 support GDB on MS-DOSe systems (which have very restrictive file name
3932 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3933 environment) is close to working but has some remaining problems. Note
3934 that debugging of DOS programs is not supported, due to limitations
3935 in the ``operating system'', but it can be used to host cross-debugging.
3937 * Cross byte order fixes
3939 Many fixes have been made to support cross debugging of Sparc and MIPS
3940 targets from hosts whose byte order differs.
3942 * New -mapped and -readnow options
3944 If memory-mapped files are available on your system through the 'mmap'
3945 system call, you can use the -mapped option on the `file' or
3946 `symbol-file' commands to cause GDB to write the symbols from your
3947 program into a reusable file. If the program you are debugging is
3948 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3949 Future GDB debugging sessions will notice the presence of this file,
3950 and will quickly map in symbol information from it, rather than reading
3951 the symbol table from the executable program. Using the '-mapped'
3952 option in a GDB `file' or `symbol-file' command has the same effect as
3953 starting GDB with the '-mapped' command-line option.
3955 You can cause GDB to read the entire symbol table immediately by using
3956 the '-readnow' option with any of the commands that load symbol table
3957 information (or on the GDB command line). This makes the command
3958 slower, but makes future operations faster.
3960 The -mapped and -readnow options are typically combined in order to
3961 build a `fred.syms' file that contains complete symbol information.
3962 A simple GDB invocation to do nothing but build a `.syms' file for future
3965 gdb -batch -nx -mapped -readnow programname
3967 The `.syms' file is specific to the host machine on which GDB is run.
3968 It holds an exact image of GDB's internal symbol table. It cannot be
3969 shared across multiple host platforms.
3971 * longjmp() handling
3973 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3974 siglongjmp() without losing control. This feature has not yet been ported to
3975 all systems. It currently works on many 386 platforms, all MIPS-based
3976 platforms (SGI, DECstation, etc), and Sun3/4.
3980 Preliminary work has been put in to support the new Solaris OS from Sun. At
3981 this time, it can control and debug processes, but it is not capable of
3986 As always, many many bug fixes. The major areas were with g++, and mipsread.
3987 People using the MIPS-based platforms should experience fewer mysterious
3988 crashes and trashed symbol tables.
3990 *** Changes in GDB-4.4:
3992 * New machines supported (host and target)
3994 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3996 BSD Reno on Vax vax-dec-bsd
3997 Ultrix on Vax vax-dec-ultrix
3999 * New machines supported (target)
4001 AMD 29000 embedded, using EBMON a29k-none-none
4005 GDB continues to improve its handling of C++. `References' work better.
4006 The demangler has also been improved, and now deals with symbols mangled as
4007 per the Annotated C++ Reference Guide.
4009 GDB also now handles `stabs' symbol information embedded in MIPS
4010 `ecoff' symbol tables. Since the ecoff format was not easily
4011 extensible to handle new languages such as C++, this appeared to be a
4012 good way to put C++ debugging info into MIPS binaries. This option
4013 will be supported in the GNU C compiler, version 2, when it is
4016 * New features for SVR4
4018 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4019 shared libraries. Debugging dynamically linked programs should present
4020 only minor differences from debugging statically linked programs.
4022 The `info proc' command will print out information about any process
4023 on an SVR4 system (including the one you are debugging). At the moment,
4024 it prints the address mappings of the process.
4026 If you bring up GDB on another SVR4 system, please send mail to
4027 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4029 * Better dynamic linking support in SunOS
4031 Reading symbols from shared libraries which contain debugging symbols
4032 now works properly. However, there remain issues such as automatic
4033 skipping of `transfer vector' code during function calls, which
4034 make it harder to debug code in a shared library, than to debug the
4035 same code linked statically.
4039 GDB is now using the latest `getopt' routines from the FSF. This
4040 version accepts the -- prefix for options with long names. GDB will
4041 continue to accept the old forms (-option and +option) as well.
4042 Various single letter abbreviations for options have been explicity
4043 added to the option table so that they won't get overshadowed in the
4044 future by other options that begin with the same letter.
4048 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4049 Many assorted bugs have been handled. Many more remain to be handled.
4050 See the various ChangeLog files (primarily in gdb and bfd) for details.
4053 *** Changes in GDB-4.3:
4055 * New machines supported (host and target)
4057 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4058 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4059 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4061 * Almost SCO Unix support
4063 We had hoped to support:
4064 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4065 (except for core file support), but we discovered very late in the release
4066 that it has problems with process groups that render gdb unusable. Sorry
4067 about that. I encourage people to fix it and post the fixes.
4069 * Preliminary ELF and DWARF support
4071 GDB can read ELF object files on System V Release 4, and can handle
4072 debugging records for C, in DWARF format, in ELF files. This support
4073 is preliminary. If you bring up GDB on another SVR4 system, please
4074 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4079 GDB now uses the latest `readline' library. One user-visible change
4080 is that two tabs will list possible command completions, which previously
4081 required typing M-? (meta-question mark, or ESC ?).
4085 The `stepi' bug that many of you noticed has been squashed.
4086 Many bugs in C++ have been handled. Many more remain to be handled.
4087 See the various ChangeLog files (primarily in gdb and bfd) for details.
4089 * State of the MIPS world (in case you wondered):
4091 GDB can understand the symbol tables emitted by the compilers
4092 supplied by most vendors of MIPS-based machines, including DEC. These
4093 symbol tables are in a format that essentially nobody else uses.
4095 Some versions of gcc come with an assembler post-processor called
4096 mips-tfile. This program is required if you want to do source-level
4097 debugging of gcc-compiled programs. I believe FSF does not ship
4098 mips-tfile with gcc version 1, but it will eventually come with gcc
4101 Debugging of g++ output remains a problem. g++ version 1.xx does not
4102 really support it at all. (If you're lucky, you should be able to get
4103 line numbers and stack traces to work, but no parameters or local
4104 variables.) With some work it should be possible to improve the
4107 When gcc version 2 is released, you will have somewhat better luck.
4108 However, even then you will get confusing results for inheritance and
4111 We will eventually provide full debugging of g++ output on
4112 DECstations. This will probably involve some kind of stabs-in-ecoff
4113 encapulation, but the details have not been worked out yet.
4116 *** Changes in GDB-4.2:
4118 * Improved configuration
4120 Only one copy of `configure' exists now, and it is not self-modifying.
4121 Porting BFD is simpler.
4125 The `step' and `next' commands now only stop at the first instruction
4126 of a source line. This prevents the multiple stops that used to occur
4127 in switch statements, for-loops, etc. `Step' continues to stop if a
4128 function that has debugging information is called within the line.
4132 Lots of small bugs fixed. More remain.
4134 * New host supported (not target)
4136 Intel 386 PC clone running Mach i386-none-mach
4139 *** Changes in GDB-4.1:
4141 * Multiple source language support
4143 GDB now has internal scaffolding to handle several source languages.
4144 It determines the type of each source file from its filename extension,
4145 and will switch expression parsing and number formatting to match the
4146 language of the function in the currently selected stack frame.
4147 You can also specifically set the language to be used, with
4148 `set language c' or `set language modula-2'.
4152 GDB now has preliminary support for the GNU Modula-2 compiler,
4153 currently under development at the State University of New York at
4154 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4155 continue through the fall of 1991 and into 1992.
4157 Other Modula-2 compilers are currently not supported, and attempting to
4158 debug programs compiled with them will likely result in an error as the
4159 symbol table is read. Feel free to work on it, though!
4161 There are hooks in GDB for strict type checking and range checking,
4162 in the `Modula-2 philosophy', but they do not currently work.
4166 GDB can now write to executable and core files (e.g. patch
4167 a variable's value). You must turn this switch on, specify
4168 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4169 by assigning a new value to a variable. Modifications take
4172 * Automatic SunOS shared library reading
4174 When you run your program, GDB automatically determines where its
4175 shared libraries (if any) have been loaded, and reads their symbols.
4176 The `share' command is no longer needed. This also works when
4177 examining core files.
4181 You can specify the number of lines that the `list' command shows.
4184 * New machines supported (host and target)
4186 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4187 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4188 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4190 * New hosts supported (not targets)
4192 IBM RT/PC: romp-ibm-aix or rtpc
4194 * New targets supported (not hosts)
4196 AMD 29000 embedded with COFF a29k-none-coff
4197 AMD 29000 embedded with a.out a29k-none-aout
4198 Ultracomputer remote kernel debug a29k-nyu-kern
4200 * New remote interfaces
4206 *** Changes in GDB-4.0:
4210 Wide output is wrapped at good places to make the output more readable.
4212 Gdb now supports cross-debugging from a host machine of one type to a
4213 target machine of another type. Communication with the target system
4214 is over serial lines. The ``target'' command handles connecting to the
4215 remote system; the ``load'' command will download a program into the
4216 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4217 also supports debugging of realtime processes running under VxWorks,
4218 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4219 stub on the target system.
4221 New CPUs supported include the AMD 29000 and Intel 960.
4223 GDB now reads object files and symbol tables via a ``binary file''
4224 library, which allows a single copy of GDB to debug programs of multiple
4225 object file types such as a.out and coff.
4227 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4228 refcard.dvi and refcard.ps are available to format it).
4231 * Control-Variable user interface simplified
4233 All variables that control the operation of the debugger can be set
4234 by the ``set'' command, and displayed by the ``show'' command.
4236 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4237 ``Show prompt'' produces the response:
4238 Gdb's prompt is new-gdb=>.
4240 What follows are the NEW set commands. The command ``help set'' will
4241 print a complete list of old and new set commands. ``help set FOO''
4242 will give a longer description of the variable FOO. ``show'' will show
4243 all of the variable descriptions and their current settings.
4245 confirm on/off: Enables warning questions for operations that are
4246 hard to recover from, e.g. rerunning the program while
4247 it is already running. Default is ON.
4249 editing on/off: Enables EMACS style command line editing
4250 of input. Previous lines can be recalled with
4251 control-P, the current line can be edited with control-B,
4252 you can search for commands with control-R, etc.
4255 history filename NAME: NAME is where the gdb command history
4256 will be stored. The default is .gdb_history,
4257 or the value of the environment variable
4260 history size N: The size, in commands, of the command history. The
4261 default is 256, or the value of the environment variable
4264 history save on/off: If this value is set to ON, the history file will
4265 be saved after exiting gdb. If set to OFF, the
4266 file will not be saved. The default is OFF.
4268 history expansion on/off: If this value is set to ON, then csh-like
4269 history expansion will be performed on
4270 command line input. The default is OFF.
4272 radix N: Sets the default radix for input and output. It can be set
4273 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4274 in the current radix, so "set radix 10" is always a no-op.
4276 height N: This integer value is the number of lines on a page. Default
4277 is 24, the current `stty rows'' setting, or the ``li#''
4278 setting from the termcap entry matching the environment
4281 width N: This integer value is the number of characters on a line.
4282 Default is 80, the current `stty cols'' setting, or the ``co#''
4283 setting from the termcap entry matching the environment
4286 Note: ``set screensize'' is obsolete. Use ``set height'' and
4287 ``set width'' instead.
4289 print address on/off: Print memory addresses in various command displays,
4290 such as stack traces and structure values. Gdb looks
4291 more ``symbolic'' if you turn this off; it looks more
4292 ``machine level'' with it on. Default is ON.
4294 print array on/off: Prettyprint arrays. New convenient format! Default
4297 print demangle on/off: Print C++ symbols in "source" form if on,
4300 print asm-demangle on/off: Same, for assembler level printouts
4303 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4306 * Support for Epoch Environment.
4308 The epoch environment is a version of Emacs v18 with windowing. One
4309 new command, ``inspect'', is identical to ``print'', except that if you
4310 are running in the epoch environment, the value is printed in its own
4314 * Support for Shared Libraries
4316 GDB can now debug programs and core files that use SunOS shared libraries.
4317 Symbols from a shared library cannot be referenced
4318 before the shared library has been linked with the program (this
4319 happens after you type ``run'' and before the function main() is entered).
4320 At any time after this linking (including when examining core files
4321 from dynamically linked programs), gdb reads the symbols from each
4322 shared library when you type the ``sharedlibrary'' command.
4323 It can be abbreviated ``share''.
4325 sharedlibrary REGEXP: Load shared object library symbols for files
4326 matching a unix regular expression. No argument
4327 indicates to load symbols for all shared libraries.
4329 info sharedlibrary: Status of loaded shared libraries.
4334 A watchpoint stops execution of a program whenever the value of an
4335 expression changes. Checking for this slows down execution
4336 tremendously whenever you are in the scope of the expression, but is
4337 quite useful for catching tough ``bit-spreader'' or pointer misuse
4338 problems. Some machines such as the 386 have hardware for doing this
4339 more quickly, and future versions of gdb will use this hardware.
4341 watch EXP: Set a watchpoint (breakpoint) for an expression.
4343 info watchpoints: Information about your watchpoints.
4345 delete N: Deletes watchpoint number N (same as breakpoints).
4346 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4347 enable N: Re-enables watchpoint number N (same as breakpoints).
4350 * C++ multiple inheritance
4352 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4355 * C++ exception handling
4357 Gdb now supports limited C++ exception handling. Besides the existing
4358 ability to breakpoint on an exception handler, gdb can breakpoint on
4359 the raising of an exception (before the stack is peeled back to the
4362 catch FOO: If there is a FOO exception handler in the dynamic scope,
4363 set a breakpoint to catch exceptions which may be raised there.
4364 Multiple exceptions (``catch foo bar baz'') may be caught.
4366 info catch: Lists all exceptions which may be caught in the
4367 current stack frame.
4370 * Minor command changes
4372 The command ``call func (arg, arg, ...)'' now acts like the print
4373 command, except it does not print or save a value if the function's result
4374 is void. This is similar to dbx usage.
4376 The ``up'' and ``down'' commands now always print the frame they end up
4377 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4378 frames without printing.
4380 * New directory command
4382 'dir' now adds directories to the FRONT of the source search path.
4383 The path starts off empty. Source files that contain debug information
4384 about the directory in which they were compiled can be found even
4385 with an empty path; Sun CC and GCC include this information. If GDB can't
4386 find your source file in the current directory, type "dir .".
4388 * Configuring GDB for compilation
4390 For normal use, type ``./configure host''. See README or gdb.texinfo
4393 GDB now handles cross debugging. If you are remotely debugging between
4394 two different machines, type ``./configure host -target=targ''.
4395 Host is the machine where GDB will run; targ is the machine
4396 where the program that you are debugging will run.