1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.2
8 * Shared library support for remote targets by default
10 When GDB is configured for a generic, non-OS specific target, like
11 for example, --target=arm-eabi or one of the many *-*-elf targets,
12 GDB now queries remote stubs for loaded shared libraries using the
13 `qXfer:libraries:read' packet. Previously, shared library support
14 was always disabled for such configurations.
18 ** Argument Dependent Lookup (ADL)
20 In C++ ADL lookup directs function search to the namespaces of its
21 arguments even if the namespace has not been imported.
31 Here the compiler will search for `foo' in the namespace of 'b'
32 and find A::foo. GDB now supports this. This construct is commonly
33 used in the Standard Template Library for operators.
35 ** Improved User Defined Operator Support
37 In addition to member operators, GDB now supports lookup of operators
38 defined in a namespace and imported with a `using' directive, operators
39 defined in the global scope, operators imported implicitly from an
40 anonymous namespace, and the ADL operators mentioned in the previous
42 GDB now also supports proper overload resolution for all the previously
43 mentioned flavors of operators.
45 ** static const class members
47 Printing of static const class members that are initialized in the
48 class definition has been fixed.
50 * Windows Thread Information Block access.
52 On Windows targets, GDB now supports displaying the Windows Thread
53 Information Block (TIB) structure. This structure is visible either
54 by using the new command `info w32 thread-information-block' or, by
55 dereferencing the new convenience variable named `$_tlb', a
56 thread-specific pointer to the TIB. This feature is also supported
57 when remote debugging using GDBserver.
61 Static tracepoints are calls in the user program into a tracing
62 library. One such library is a port of the LTTng kernel tracer to
63 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
64 When debugging with GDBserver, GDB now supports combining the GDB
65 tracepoint machinery with such libraries. For example: the user can
66 use GDB to probe a static tracepoint marker (a call from the user
67 program into the tracing library) with the new "strace" command (see
68 "New commands" below). This creates a "static tracepoint" in the
69 breakpoint list, that can be manipulated with the same feature set
70 as fast and regular tracepoints. E.g., collect registers, local and
71 global variables, collect trace state variables, and define
72 tracepoint conditions. In addition, the user can collect extra
73 static tracepoint marker specific data, by collecting the new
74 $_sdata internal variable. When analyzing the trace buffer, you can
75 inspect $_sdata like any other variable available to GDB. For more
76 information, see the "Tracepoints" chapter in GDB user manual. New
77 remote packets have been defined to support static tracepoints, see
78 the "New remote packets" section below.
84 Return the address of the Windows Thread Information Block of a given thread.
88 In response to several of the tracepoint packets, the target may now
89 also respond with a number of intermediate `qRelocInsn' request
90 packets before the final result packet, to have GDB handle
91 relocating an instruction to execute at a different address. This
92 is particularly useful for stubs that support fast tracepoints. GDB
93 reports support for this feature in the qSupported packet.
97 List static tracepoint markers in the target program.
101 List static tracepoint markers at a given address in the target
104 qXfer:statictrace:read
106 Read the static trace data collected (by a `collect $_sdata'
107 tracepoint action). The remote stub reports support for this packet
108 to gdb's qSupported query.
110 * The source command now accepts a -s option to force searching for the
111 script in the source search path even if the script name specifies
114 * New features in the GDB remote stub, GDBserver
116 - GDBserver now support tracepoints (including fast tracepoints, and
117 static tracepoints). The feature is currently supported by the
118 i386-linux and amd64-linux builds. See the "Tracepoints support
119 in gdbserver" section in the manual for more information.
121 GDBserver JIT compiles the tracepoint's conditional agent
122 expression bytecode into native code whenever possible for low
123 overhead dynamic tracepoints conditionals. For such tracepoints,
124 an expression that examines program state is evaluated when the
125 tracepoint is reached, in order to determine whether to capture
126 trace data. If the condition is simple and false, processing the
127 tracepoint finishes very quickly and no data is gathered.
129 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
130 for static tracepoints support.
132 - GDBserver now supports x86_64 Windows 64-bit debugging.
134 * GDB now sends xmlRegisters= in qSupported packet to indicate that
135 it understands register description.
137 * The --batch flag now disables pagination and queries.
139 * X86 general purpose registers
141 GDB now supports reading/writing byte, word and double-word x86
142 general purpose registers directly. This means you can use, say,
143 $ah or $ax to refer, respectively, to the byte register AH and
144 16-bit word register AX that are actually portions of the 32-bit
145 register EAX or 64-bit register RAX.
147 * The `commands' command now accepts a range of breakpoints to modify.
148 A plain `commands' following a command that creates multiple
149 breakpoints affects all the breakpoints set by that command. This
150 applies to breakpoints set by `rbreak', and also applies when a
151 single `break' command creates multiple breakpoints (e.g.,
152 breakpoints on overloaded c++ functions).
154 * The `rbreak' command now accepts a filename specification as part of
155 its argument, limiting the functions selected by the regex to those
156 in the specified file.
158 * Support for remote debugging Windows and SymbianOS shared libraries
159 from Unix hosts has been improved. Non Windows GDB builds now can
160 understand target reported file names that follow MS-DOS based file
161 system semantics, such as file names that include drive letters and
162 use the backslash character as directory separator. This makes it
163 possible to transparently use the "set sysroot" and "set
164 solib-search-path" on Unix hosts to point as host copies of the
165 target's shared libraries. See the new command "set
166 target-file-system-kind" described below, and the "Commands to
167 specify files" section in the user manual for more information.
171 eval template, expressions...
172 Convert the values of one or more expressions under the control
173 of the string template to a command line, and call it.
175 set target-file-system-kind unix|dos-based|auto
176 show target-file-system-kind
177 Set or show the assumed file system kind for target reported file
180 save breakpoints <filename>
181 Save all current breakpoint definitions to a file suitable for use
182 in a later debugging session. To read the saved breakpoint
183 definitions, use the `source' command.
185 `save tracepoints' is a new alias for `save-tracepoints'. The latter
188 info static-tracepoint-markers
189 Display information about static tracepoint markers in the target.
191 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
192 Define a static tracepoint by probing a marker at the given
193 function, line, address, or marker ID.
197 ** GDB now provides a new directory location, called the python directory,
198 where Python scripts written for GDB can be installed. The location
199 of that directory is <data-directory>/python, where <data-directory>
200 is the GDB data directory. For more details, see section `Scripting
201 GDB using Python' in the manual.
203 ** The GDB Python API now has access to breakpoints, symbols, symbol
204 tables, program spaces, inferiors, threads and frame's code blocks.
205 Additionally, GDB Parameters can now be created from the API, and
206 manipulated via set/show in the CLI.
208 ** New functions gdb.target_charset, gdb.target_wide_charset,
209 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
211 ** New exception gdb.GdbError.
213 ** Pretty-printers are now also looked up in the current program space.
215 ** Pretty-printers can now be individually enabled and disabled.
217 ** GDB now looks for names of Python scripts to auto-load in a
218 special section named `.debug_gdb_scripts', in addition to looking
219 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
221 * Tracepoint actions were unified with breakpoint commands. In particular,
222 there are no longer differences in "info break" output for breakpoints and
223 tracepoints and the "commands" command can be used for both tracepoints and
228 ARM Symbian arm*-*-symbianelf*
230 * D language support.
231 GDB now supports debugging programs written in the D programming
234 * GDB now supports the extended ptrace interface for PowerPC which is
235 available since Linux kernel version 2.6.34. This automatically enables
236 any hardware breakpoints and additional hardware watchpoints available in
237 the processor. The old ptrace interface exposes just one hardware
238 watchpoint and no hardware breakpoints.
240 * GDB is now able to use the Data Value Compare (DVC) register available on
241 embedded PowerPC processors to implement in hardware simple watchpoint
242 conditions of the form:
244 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
246 This works in native GDB running on Linux kernels with the extended ptrace
247 interface mentioned above.
249 *** Changes in GDB 7.1
255 GDB now supports importing of namespaces in C++. This enables the
256 user to inspect variables from imported namespaces. Support for
257 namepace aliasing has also been added. So, if a namespace is
258 aliased in the current scope (e.g. namepace C=A; ) the user can
259 print variables using the alias (e.g. (gdb) print C::x).
263 All known bugs relating to the printing of virtual base class were
264 fixed. It is now possible to call overloaded static methods using a
269 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
270 and reinterpret_cast<> are now handled by the C++ expression parser.
274 Xilinx MicroBlaze microblaze-*-*
279 Xilinx MicroBlaze microblaze
282 * Multi-program debugging.
284 GDB now has support for multi-program (a.k.a. multi-executable or
285 multi-exec) debugging. This allows for debugging multiple inferiors
286 simultaneously each running a different program under the same GDB
287 session. See "Debugging Multiple Inferiors and Programs" in the
288 manual for more information. This implied some user visible changes
289 in the multi-inferior support. For example, "info inferiors" now
290 lists inferiors that are not running yet or that have exited
291 already. See also "New commands" and "New options" below.
293 * New tracing features
295 GDB's tracepoint facility now includes several new features:
297 ** Trace state variables
299 GDB tracepoints now include support for trace state variables, which
300 are variables managed by the target agent during a tracing
301 experiment. They are useful for tracepoints that trigger each
302 other, so for instance one tracepoint can count hits in a variable,
303 and then a second tracepoint has a condition that is true when the
304 count reaches a particular value. Trace state variables share the
305 $-syntax of GDB convenience variables, and can appear in both
306 tracepoint actions and condition expressions. Use the "tvariable"
307 command to create, and "info tvariables" to view; see "Trace State
308 Variables" in the manual for more detail.
312 GDB now includes an option for defining fast tracepoints, which
313 targets may implement more efficiently, such as by installing a jump
314 into the target agent rather than a trap instruction. The resulting
315 speedup can be by two orders of magnitude or more, although the
316 tradeoff is that some program locations on some target architectures
317 might not allow fast tracepoint installation, for instance if the
318 instruction to be replaced is shorter than the jump. To request a
319 fast tracepoint, use the "ftrace" command, with syntax identical to
320 the regular trace command.
322 ** Disconnected tracing
324 It is now possible to detach GDB from the target while it is running
325 a trace experiment, then reconnect later to see how the experiment
326 is going. In addition, a new variable disconnected-tracing lets you
327 tell the target agent whether to continue running a trace if the
328 connection is lost unexpectedly.
332 GDB now has the ability to save the trace buffer into a file, and
333 then use that file as a target, similarly to you can do with
334 corefiles. You can select trace frames, print data that was
335 collected in them, and use tstatus to display the state of the
336 tracing run at the moment that it was saved. To create a trace
337 file, use "tsave <filename>", and to use it, do "target tfile
340 ** Circular trace buffer
342 You can ask the target agent to handle the trace buffer as a
343 circular buffer, discarding the oldest trace frames to make room for
344 newer ones, by setting circular-trace-buffer to on. This feature may
345 not be available for all target agents.
350 The disassemble command, when invoked with two arguments, now requires
351 the arguments to be comma-separated.
354 The info variables command now displays variable definitions. Files
355 which only declare a variable are not shown.
358 The source command is now capable of sourcing Python scripts.
359 This feature is dependent on the debugger being build with Python
362 Related to this enhancement is also the introduction of a new command
363 "set script-extension" (see below).
365 * New commands (for set/show, see "New options" below)
367 record save [<FILENAME>]
368 Save a file (in core file format) containing the process record
369 execution log for replay debugging at a later time.
371 record restore <FILENAME>
372 Restore the process record execution log that was saved at an
373 earlier time, for replay debugging.
375 add-inferior [-copies <N>] [-exec <FILENAME>]
378 clone-inferior [-copies <N>] [ID]
379 Make a new inferior ready to execute the same program another
385 maint info program-spaces
386 List the program spaces loaded into GDB.
388 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
389 show remote interrupt-sequence
390 Allow the user to select one of ^C, a BREAK signal or BREAK-g
391 as the sequence to the remote target in order to interrupt the execution.
392 Ctrl-C is a default. Some system prefers BREAK which is high level of
393 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
394 Magic SysRq g. It is BREAK signal and character 'g'.
396 set remote interrupt-on-connect [on | off]
397 show remote interrupt-on-connect
398 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
399 remote target when gdb connects to it. This is needed when you debug
402 set remotebreak [on | off]
404 Deprecated. Use "set/show remote interrupt-sequence" instead.
406 tvariable $NAME [ = EXP ]
407 Create or modify a trace state variable.
410 List trace state variables and their values.
412 delete tvariable $NAME ...
413 Delete one or more trace state variables.
416 Evaluate the given expressions without collecting anything into the
417 trace buffer. (Valid in tracepoint actions only.)
419 ftrace FN / FILE:LINE / *ADDR
420 Define a fast tracepoint at the given function, line, or address.
422 * New expression syntax
424 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
425 GDB now parses 0b101010 identically with 42.
429 set follow-exec-mode new|same
430 show follow-exec-mode
431 Control whether GDB reuses the same inferior across an exec call or
432 creates a new one. This is useful to be able to restart the old
433 executable after the inferior having done an exec call.
435 set default-collect EXPR, ...
437 Define a list of expressions to be collected at each tracepoint.
438 This is a useful way to ensure essential items are not overlooked,
439 such as registers or a critical global variable.
441 set disconnected-tracing
442 show disconnected-tracing
443 If set to 1, the target is instructed to continue tracing if it
444 loses its connection to GDB. If 0, the target is to stop tracing
447 set circular-trace-buffer
448 show circular-trace-buffer
449 If set to on, the target is instructed to use a circular trace buffer
450 and discard the oldest trace frames instead of stopping the trace due
451 to a full trace buffer. If set to off, the trace stops when the buffer
452 fills up. Some targets may not support this.
454 set script-extension off|soft|strict
455 show script-extension
456 If set to "off", the debugger does not perform any script language
457 recognition, and all sourced files are assumed to be GDB scripts.
458 If set to "soft" (the default), files are sourced according to
459 filename extension, falling back to GDB scripts if the first
461 If set to "strict", files are sourced according to filename extension.
463 set ada trust-PAD-over-XVS on|off
464 show ada trust-PAD-over-XVS
465 If off, activate a workaround against a bug in the debugging information
466 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
467 the GCC sources for more information about the GNAT encoding and
468 PAD types in particular). It is always safe to set this option to
469 off, but this introduces a slight performance penalty. The default
472 * Python API Improvements
474 ** GDB provides the new class gdb.LazyString. This is useful in
475 some pretty-printing cases. The new method gdb.Value.lazy_string
476 provides a simple way to create objects of this type.
478 ** The fields returned by gdb.Type.fields now have an
479 `is_base_class' attribute.
481 ** The new method gdb.Type.range returns the range of an array type.
483 ** The new method gdb.parse_and_eval can be used to parse and
484 evaluate an expression.
489 Define a trace state variable.
492 Get the current value of a trace state variable.
495 Set desired tracing behavior upon disconnection.
498 Set the trace buffer to be linear or circular.
501 Get data about the tracepoints currently in use.
505 Process record now works correctly with hardware watchpoints.
507 Multiple bug fixes have been made to the mips-irix port, making it
508 much more reliable. In particular:
509 - Debugging threaded applications is now possible again. Previously,
510 GDB would hang while starting the program, or while waiting for
511 the program to stop at a breakpoint.
512 - Attaching to a running process no longer hangs.
513 - An error occurring while loading a core file has been fixed.
514 - Changing the value of the PC register now works again. This fixes
515 problems observed when using the "jump" command, or when calling
516 a function from GDB, or even when assigning a new value to $pc.
517 - With the "finish" and "return" commands, the return value for functions
518 returning a small array is now correctly printed.
519 - It is now possible to break on shared library code which gets executed
520 during a shared library init phase (code executed while executing
521 their .init section). Previously, the breakpoint would have no effect.
522 - GDB is now able to backtrace through the signal handler for
523 non-threaded programs.
525 PIE (Position Independent Executable) programs debugging is now supported.
526 This includes debugging execution of PIC (Position Independent Code) shared
527 libraries although for that, it should be possible to run such libraries as an
530 *** Changes in GDB 7.0
532 * GDB now has an interface for JIT compilation. Applications that
533 dynamically generate code can create symbol files in memory and register
534 them with GDB. For users, the feature should work transparently, and
535 for JIT developers, the interface is documented in the GDB manual in the
536 "JIT Compilation Interface" chapter.
538 * Tracepoints may now be conditional. The syntax is as for
539 breakpoints; either an "if" clause appended to the "trace" command,
540 or the "condition" command is available. GDB sends the condition to
541 the target for evaluation using the same bytecode format as is used
542 for tracepoint actions.
544 * "disassemble" command with a /r modifier, print the raw instructions
545 in hex as well as in symbolic form.
547 * Process record and replay
549 In a architecture environment that supports ``process record and
550 replay'', ``process record and replay'' target can record a log of
551 the process execution, and replay it with both forward and reverse
554 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
555 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
556 set execution-direction {forward|reverse}, for targets that support
559 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
560 feature is available with a native GDB running on kernel version
563 * GDB now has support for multi-byte and wide character sets on the
564 target. Strings whose character type is wchar_t, char16_t, or
565 char32_t are now correctly printed. GDB supports wide- and unicode-
566 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
567 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
568 `printf'. This feature requires iconv to work properly; if your
569 system does not have a working iconv, GDB can use GNU libiconv. See
570 the installation instructions for more information.
572 * GDB now supports automatic retrieval of shared library files from
573 remote targets. To use this feature, specify a system root that begins
574 with the `remote:' prefix, either via the `set sysroot' command or via
575 the `--with-sysroot' configure-time option.
577 * "info sharedlibrary" now takes an optional regex of libraries to show,
578 and it now reports if a shared library has no debugging information.
580 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
581 now complete on file names.
583 * When completing in expressions, gdb will attempt to limit
584 completions to allowable structure or union fields, where appropriate.
585 For instance, consider:
587 # struct example { int f1; double f2; };
588 # struct example variable;
591 If the user types TAB at the end of this command line, the available
592 completions will be "f1" and "f2".
594 * Inlined functions are now supported. They show up in backtraces, and
595 the "step", "next", and "finish" commands handle them automatically.
597 * GDB now supports the token-splicing (##) and stringification (#)
598 operators when expanding macros. It also supports variable-arity
601 * GDB now supports inspecting extra signal information, exported by
602 the new $_siginfo convenience variable. The feature is currently
603 implemented on linux ARM, i386 and amd64.
605 * GDB can now display the VFP floating point registers and NEON vector
606 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
607 can provide these registers (requires Linux 2.6.30 or later). Remote
608 and simulator targets may also provide them.
613 Search memory for a sequence of bytes.
616 Turn off `+'/`-' protocol acknowledgments to permit more efficient
617 operation over reliable transport links. Use of this packet is
618 controlled by the `set remote noack-packet' command.
621 Kill the process with the specified process ID. Use this in preference
622 to `k' when multiprocess protocol extensions are supported.
625 Obtains additional operating system information
629 Read or write additional signal information.
631 * Removed remote protocol undocumented extension
633 An undocumented extension to the remote protocol's `S' stop reply
634 packet that permited the stub to pass a process id was removed.
635 Remote servers should use the `T' stop reply packet instead.
637 * The "disassemble" command now supports an optional /m modifier to print mixed
640 * GDB now supports multiple function calling conventions according to the
641 DWARF-2 DW_AT_calling_convention function attribute.
643 * The SH target utilizes the aforementioned change to distinguish between gcc
644 and Renesas calling convention. It also adds the new CLI commands
645 `set/show sh calling-convention'.
647 * GDB can now read compressed debug sections, as produced by GNU gold
648 with the --compress-debug-sections=zlib flag.
650 * 64-bit core files are now supported on AIX.
652 * Thread switching is now supported on Tru64.
654 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
655 which will be allocated using malloc later in program execution.
657 * The qXfer:libraries:read remote procotol packet now allows passing a
658 list of section offsets.
660 * On GNU/Linux, GDB can now attach to stopped processes. Several race
661 conditions handling signals delivered during attach or thread creation
662 have also been fixed.
664 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
665 From the user's standpoint, all unqualified instances of True and False
666 are treated as the standard definitions, regardless of context.
668 * GDB now parses C++ symbol and type names more flexibly. For
671 template<typename T> class C { };
674 GDB will now correctly handle all of:
676 ptype C<char const *>
678 ptype C<const char *>
681 * New features in the GDB remote stub, gdbserver
683 - The "--wrapper" command-line argument tells gdbserver to use a
684 wrapper program to launch programs for debugging.
686 - On PowerPC and S/390 targets, it is now possible to use a single
687 gdbserver executable to debug both 32-bit and 64-bit programs.
688 (This requires gdbserver itself to be built as a 64-bit executable.)
690 - gdbserver uses the new noack protocol mode for TCP connections to
691 reduce communications latency, if also supported and enabled in GDB.
693 - Support for the sparc64-linux-gnu target is now included in
696 - The amd64-linux build of gdbserver now supports debugging both
697 32-bit and 64-bit programs.
699 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
700 now support hardware watchpoints, and will use them automatically
705 GDB now has support for scripting using Python. Whether this is
706 available is determined at configure time.
708 New GDB commands can now be written in Python.
710 * Ada tasking support
712 Ada tasks can now be inspected in GDB. The following commands have
716 Print the list of Ada tasks.
718 Print detailed information about task number N.
720 Print the task number of the current task.
722 Switch the context of debugging to task number N.
724 * Support for user-defined prefixed commands. The "define" command can
725 add new commands to existing prefixes, e.g. "target".
727 * Multi-inferior, multi-process debugging.
729 GDB now has generalized support for multi-inferior debugging. See
730 "Debugging Multiple Inferiors" in the manual for more information.
731 Although availability still depends on target support, the command
732 set is more uniform now. The GNU/Linux specific multi-forks support
733 has been migrated to this new framework. This implied some user
734 visible changes; see "New commands" and also "Removed commands"
737 * Target descriptions can now describe the target OS ABI. See the
738 "Target Description Format" section in the user manual for more
741 * Target descriptions can now describe "compatible" architectures
742 to indicate that the target can execute applications for a different
743 architecture in addition to those for the main target architecture.
744 See the "Target Description Format" section in the user manual for
747 * Multi-architecture debugging.
749 GDB now includes general supports for debugging applications on
750 hybrid systems that use more than one single processor architecture
751 at the same time. Each such hybrid architecture still requires
752 specific support to be added. The only hybrid architecture supported
753 in this version of GDB is the Cell Broadband Engine.
755 * GDB now supports integrated debugging of Cell/B.E. applications that
756 use both the PPU and SPU architectures. To enable support for hybrid
757 Cell/B.E. debugging, you need to configure GDB to support both the
758 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
759 --enable-targets configure option.
761 * Non-stop mode debugging.
763 For some targets, GDB now supports an optional mode of operation in
764 which you can examine stopped threads while other threads continue
765 to execute freely. This is referred to as non-stop mode, with the
766 old mode referred to as all-stop mode. See the "Non-Stop Mode"
767 section in the user manual for more information.
769 To be able to support remote non-stop debugging, a remote stub needs
770 to implement the non-stop mode remote protocol extensions, as
771 described in the "Remote Non-Stop" section of the user manual. The
772 GDB remote stub, gdbserver, has been adjusted to support these
773 extensions on linux targets.
775 * New commands (for set/show, see "New options" below)
777 catch syscall [NAME(S) | NUMBER(S)]
778 Catch system calls. Arguments, which should be names of system
779 calls or their numbers, mean catch only those syscalls. Without
780 arguments, every syscall will be caught. When the inferior issues
781 any of the specified syscalls, GDB will stop and announce the system
782 call, both when it is called and when its call returns. This
783 feature is currently available with a native GDB running on the
784 Linux Kernel, under the following architectures: x86, x86_64,
785 PowerPC and PowerPC64.
787 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
789 Search memory for a sequence of bytes.
791 maint set python print-stack
792 maint show python print-stack
793 Show a stack trace when an error is encountered in a Python script.
796 Invoke CODE by passing it to the Python interpreter.
801 These allow macros to be defined, undefined, and listed
805 Show operating system information about processes.
808 List the inferiors currently under GDB's control.
811 Switch focus to inferior number NUM.
814 Detach from inferior number NUM.
817 Kill inferior number NUM.
822 show spu stop-on-load
823 Control whether to stop for new SPE threads during Cell/B.E. debugging.
825 set spu auto-flush-cache
826 show spu auto-flush-cache
827 Control whether to automatically flush the software-managed cache
828 during Cell/B.E. debugging.
830 set sh calling-convention
831 show sh calling-convention
832 Control the calling convention used when calling SH target functions.
836 Control display of timestamps with GDB debugging output.
838 set disassemble-next-line
839 show disassemble-next-line
840 Control display of disassembled source lines or instructions when
843 set remote noack-packet
844 show remote noack-packet
845 Set/show the use of remote protocol QStartNoAckMode packet. See above
846 under "New remote packets."
848 set remote query-attached-packet
849 show remote query-attached-packet
850 Control use of remote protocol `qAttached' (query-attached) packet.
852 set remote read-siginfo-object
853 show remote read-siginfo-object
854 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
857 set remote write-siginfo-object
858 show remote write-siginfo-object
859 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
862 set remote reverse-continue
863 show remote reverse-continue
864 Control use of remote protocol 'bc' (reverse-continue) packet.
866 set remote reverse-step
867 show remote reverse-step
868 Control use of remote protocol 'bs' (reverse-step) packet.
870 set displaced-stepping
871 show displaced-stepping
872 Control displaced stepping mode. Displaced stepping is a way to
873 single-step over breakpoints without removing them from the debuggee.
874 Also known as "out-of-line single-stepping".
878 Control display of debugging info for displaced stepping.
880 maint set internal-error
881 maint show internal-error
882 Control what GDB does when an internal error is detected.
884 maint set internal-warning
885 maint show internal-warning
886 Control what GDB does when an internal warning is detected.
891 Use a wrapper program to launch programs for debugging.
893 set multiple-symbols (all|ask|cancel)
894 show multiple-symbols
895 The value of this variable can be changed to adjust the debugger behavior
896 when an expression or a breakpoint location contains an ambiguous symbol
897 name (an overloaded function name, for instance).
899 set breakpoint always-inserted
900 show breakpoint always-inserted
901 Keep breakpoints always inserted in the target, as opposed to inserting
902 them when resuming the target, and removing them when the target stops.
903 This option can improve debugger performance on slow remote targets.
905 set arm fallback-mode (arm|thumb|auto)
906 show arm fallback-mode
907 set arm force-mode (arm|thumb|auto)
909 These commands control how ARM GDB determines whether instructions
910 are ARM or Thumb. The default for both settings is auto, which uses
911 the current CPSR value for instructions without symbols; previous
912 versions of GDB behaved as if "set arm fallback-mode arm".
914 set disable-randomization
915 show disable-randomization
916 Standalone programs run with the virtual address space randomization enabled
917 by default on some platforms. This option keeps the addresses stable across
918 multiple debugging sessions.
922 Control whether other threads are stopped or not when some thread hits
927 Requests that asynchronous execution is enabled in the target, if available.
928 In this case, it's possible to resume target in the background, and interact
929 with GDB while the target is running. "show target-async" displays the
930 current state of asynchronous execution of the target.
932 set target-wide-charset
933 show target-wide-charset
934 The target-wide-charset is the name of the character set that GDB
935 uses when printing characters whose type is wchar_t.
937 set tcp auto-retry (on|off)
939 set tcp connect-timeout
940 show tcp connect-timeout
941 These commands allow GDB to retry failed TCP connections to a remote stub
942 with a specified timeout period; this is useful if the stub is launched
943 in parallel with GDB but may not be ready to accept connections immediately.
945 set libthread-db-search-path
946 show libthread-db-search-path
947 Control list of directories which GDB will search for appropriate
950 set schedule-multiple (on|off)
951 show schedule-multiple
952 Allow GDB to resume all threads of all processes or only threads of
957 Use more aggressive caching for accesses to the stack. This improves
958 performance of remote debugging (particularly backtraces) without
959 affecting correctness.
961 set interactive-mode (on|off|auto)
962 show interactive-mode
963 Control whether GDB runs in interactive mode (on) or not (off).
964 When in interactive mode, GDB waits for the user to answer all
965 queries. Otherwise, GDB does not wait and assumes the default
966 answer. When set to auto (the default), GDB determines which
967 mode to use based on the stdin settings.
972 For program forks, this is replaced by the new more generic `info
973 inferiors' command. To list checkpoints, you can still use the
974 `info checkpoints' command, which was an alias for the `info forks'
978 Replaced by the new `inferior' command. To switch between
979 checkpoints, you can still use the `restart' command, which was an
980 alias for the `fork' command.
983 This is removed, since some targets don't have a notion of
984 processes. To switch between processes, you can still use the
985 `inferior' command using GDB's own inferior number.
988 For program forks, this is replaced by the new more generic `kill
989 inferior' command. To delete a checkpoint, you can still use the
990 `delete checkpoint' command, which was an alias for the `delete
994 For program forks, this is replaced by the new more generic `detach
995 inferior' command. To detach a checkpoint, you can still use the
996 `detach checkpoint' command, which was an alias for the `detach
999 * New native configurations
1001 x86/x86_64 Darwin i[34567]86-*-darwin*
1003 x86_64 MinGW x86_64-*-mingw*
1007 Lattice Mico32 lm32-*
1008 x86 DICOS i[34567]86-*-dicos*
1009 x86_64 DICOS x86_64-*-dicos*
1012 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1013 (mingw32ce) debugging.
1019 These commands were actually not implemented on any target.
1021 *** Changes in GDB 6.8
1023 * New native configurations
1025 NetBSD/hppa hppa*-*netbsd*
1026 Xtensa GNU/Linux xtensa*-*-linux*
1030 NetBSD/hppa hppa*-*-netbsd*
1031 Xtensa GNU/Lunux xtensa*-*-linux*
1033 * Change in command line behavior -- corefiles vs. process ids.
1035 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1036 attaching to process NUMBER fails, GDB no longer attempts to open a
1037 core file named NUMBER. Attaching to a program using the -c option
1038 is no longer supported. Instead, use the '-p' or '--pid' options.
1040 * GDB can now be built as a native debugger for debugging Windows x86
1041 (mingw32) Portable Executable (PE) programs.
1043 * Pending breakpoints no longer change their number when their address
1046 * GDB now supports breakpoints with multiple locations,
1047 including breakpoints on C++ constructors, inside C++ templates,
1048 and in inlined functions.
1050 * GDB's ability to debug optimized code has been improved. GDB more
1051 accurately identifies function bodies and lexical blocks that occupy
1052 more than one contiguous range of addresses.
1054 * Target descriptions can now describe registers for PowerPC.
1056 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1057 registers on PowerPC targets.
1059 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1060 targets even when the libthread_db library is not available.
1062 * The GDB remote stub, gdbserver, now supports the new file transfer
1063 commands (remote put, remote get, and remote delete).
1065 * The GDB remote stub, gdbserver, now supports run and attach in
1066 extended-remote mode.
1068 * hppa*64*-*-hpux11* target broken
1069 The debugger is unable to start a program and fails with the following
1070 error: "Error trying to get information about dynamic linker".
1071 The gdb-6.7 release is also affected.
1073 * GDB now supports the --enable-targets= configure option to allow
1074 building a single GDB executable that supports multiple remote
1075 target architectures.
1077 * GDB now supports debugging C and C++ programs which use the
1078 Decimal Floating Point extension. In addition, the PowerPC target
1079 now has a set of pseudo-registers to inspect decimal float values
1080 stored in two consecutive float registers.
1082 * The -break-insert MI command can optionally create pending
1085 * Improved support for debugging Ada
1086 Many improvements to the Ada language support have been made. These
1088 - Better support for Ada2005 interface types
1089 - Improved handling of arrays and slices in general
1090 - Better support for Taft-amendment types
1091 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1093 - Improved command completion in Ada
1096 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1101 set print frame-arguments (all|scalars|none)
1102 show print frame-arguments
1103 The value of this variable can be changed to control which argument
1104 values should be printed by the debugger when displaying a frame.
1109 Transfer files to and from a remote target, and delete remote files.
1116 Transfer files to and from a remote target, and delete remote files.
1118 * New remote packets
1125 Open, close, read, write, and delete files on the remote system.
1128 Attach to an existing process on the remote system, in extended-remote
1132 Run a new process on the remote system, in extended-remote mode.
1134 *** Changes in GDB 6.7
1136 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1137 bfd, libiberty and opcodes, as revealed by static analysis donated by
1138 Coverity, Inc. (http://scan.coverity.com).
1140 * When looking up multiply-defined global symbols, GDB will now prefer the
1141 symbol definition in the current shared library if it was built using the
1142 -Bsymbolic linker option.
1144 * When the Text User Interface (TUI) is not configured, GDB will now
1145 recognize the -tui command-line option and print a message that the TUI
1148 * The GDB remote stub, gdbserver, now has lower overhead for high
1149 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1151 * GDB for MIPS targets now autodetects whether a remote target provides
1152 32-bit or 64-bit register values.
1154 * Support for C++ member pointers has been improved.
1156 * GDB now understands XML target descriptions, which specify the
1157 target's overall architecture. GDB can read a description from
1158 a local file or over the remote serial protocol.
1160 * Vectors of single-byte data use a new integer type which is not
1161 automatically displayed as character or string data.
1163 * The /s format now works with the print command. It displays
1164 arrays of single-byte integers and pointers to single-byte integers
1167 * Target descriptions can now describe target-specific registers,
1168 for architectures which have implemented the support (currently
1169 only ARM, M68K, and MIPS).
1171 * GDB and the GDB remote stub, gdbserver, now support the XScale
1174 * The GDB remote stub, gdbserver, has been updated to support
1175 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1176 has been rewritten to use the standard GDB remote protocol.
1178 * GDB can now step into C++ functions which are called through thunks.
1180 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1182 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1183 layout. It also supports a TextSeg= and DataSeg= response when only
1184 segment base addresses (rather than offsets) are available.
1186 * The /i format now outputs any trailing branch delay slot instructions
1187 immediately following the last instruction within the count specified.
1189 * The GDB remote protocol "T" stop reply packet now supports a
1190 "library" response. Combined with the new "qXfer:libraries:read"
1191 packet, this response allows GDB to debug shared libraries on targets
1192 where the operating system manages the list of loaded libraries (e.g.
1193 Windows and SymbianOS).
1195 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1196 (DLLs) on Windows and Windows CE targets.
1198 * GDB now supports a faster verification that a .debug file matches its binary
1199 according to its build-id signature, if the signature is present.
1205 Enable or disable hardware flow control (RTS/CTS) on the serial port
1206 when debugging using remote targets.
1208 set mem inaccessible-by-default
1209 show mem inaccessible-by-default
1210 If the target supplies a memory map, for instance via the remote
1211 protocol's "qXfer:memory-map:read" packet, setting this variable
1212 prevents GDB from accessing memory outside the memory map. This
1213 is useful for targets with memory mapped registers or which react
1214 badly to accesses of unmapped address space.
1216 set breakpoint auto-hw
1217 show breakpoint auto-hw
1218 If the target supplies a memory map, for instance via the remote
1219 protocol's "qXfer:memory-map:read" packet, setting this variable
1220 lets GDB use hardware breakpoints automatically for memory regions
1221 where it can not use software breakpoints. This covers both the
1222 "break" command and internal breakpoints used for other commands
1223 including "next" and "finish".
1226 catch exception unhandled
1227 Stop the program execution when Ada exceptions are raised.
1230 Stop the program execution when an Ada assertion failed.
1234 Set an alternate system root for target files. This is a more
1235 general version of "set solib-absolute-prefix", which is now
1236 an alias to "set sysroot".
1239 Provide extended SPU facility status information. This set of
1240 commands is available only when debugging the Cell/B.E. SPU
1243 * New native configurations
1245 OpenBSD/sh sh*-*openbsd*
1248 unset tdesc filename
1250 Use the specified local file as an XML target description, and do
1251 not query the target for its built-in description.
1255 OpenBSD/sh sh*-*-openbsd*
1256 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1257 Toshiba Media Processor mep-elf
1259 * New remote packets
1262 Ignore the specified signals; pass them directly to the debugged program
1263 without stopping other threads or reporting them to GDB.
1265 qXfer:features:read:
1266 Read an XML target description from the target, which describes its
1271 Read or write contents of an spufs file on the target system. These
1272 packets are available only on the Cell/B.E. SPU architecture.
1274 qXfer:libraries:read:
1275 Report the loaded shared libraries. Combined with new "T" packet
1276 response, this packet allows GDB to debug shared libraries on
1277 targets where the operating system manages the list of loaded
1278 libraries (e.g. Windows and SymbianOS).
1282 Support for these obsolete configurations has been removed.
1290 i[34567]86-*-lynxos*
1291 i[34567]86-*-netware*
1292 i[34567]86-*-sco3.2v5*
1293 i[34567]86-*-sco3.2v4*
1295 i[34567]86-*-sysv4.2*
1298 i[34567]86-*-unixware2*
1299 i[34567]86-*-unixware*
1308 * Other removed features
1315 Various m68k-only ROM monitors.
1322 Various Renesas ROM monitors and debugging interfaces for SH and
1327 Support for a Macraigor serial interface to on-chip debugging.
1328 GDB does not directly support the newer parallel or USB
1333 A debug information format. The predecessor to DWARF 2 and
1334 DWARF 3, which are still supported.
1336 Support for the HP aCC compiler on HP-UX/PA-RISC
1338 SOM-encapsulated symbolic debugging information, automatic
1339 invocation of pxdb, and the aCC custom C++ ABI. This does not
1340 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1341 with aCC can still be debugged on an assembly level.
1343 MIPS ".pdr" sections
1345 A MIPS-specific format used to describe stack frame layout
1346 in debugging information.
1350 GDB could work with an older version of Guile to debug
1351 the interpreter and Scheme programs running in it.
1353 set mips stack-arg-size
1354 set mips saved-gpreg-size
1356 Use "set mips abi" to control parameter passing for MIPS.
1358 *** Changes in GDB 6.6
1363 Cell Broadband Engine SPU spu-elf
1365 * GDB can now be configured as a cross-debugger targeting native Windows
1366 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1367 running on a Windows system over TCP/IP to debug Windows programs.
1369 * The GDB remote stub, gdbserver, has been updated to support Windows and
1370 Cygwin debugging. Both single-threaded and multi-threaded programs are
1373 * The "set trust-readonly-sections" command works again. This command was
1374 broken in GDB 6.3, 6.4, and 6.5.
1376 * The "load" command now supports writing to flash memory, if the remote
1377 stub provides the required support.
1379 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1380 longer requires symbolic debug information (e.g. DWARF-2).
1385 unset substitute-path
1386 show substitute-path
1387 Manage a list of substitution rules that GDB uses to rewrite the name
1388 of the directories where the sources are located. This can be useful
1389 for instance when the sources were moved to a different location
1390 between compilation and debugging.
1394 Print each CLI command as it is executed. Each command is prefixed with
1395 a number of `+' symbols representing the nesting depth.
1396 The source command now has a `-v' option to enable the same feature.
1400 The ARM Demon monitor support (RDP protocol, "target rdp").
1402 Kernel Object Display, an embedded debugging feature which only worked with
1403 an obsolete version of Cisco IOS.
1405 The 'set download-write-size' and 'show download-write-size' commands.
1407 * New remote packets
1410 Tell a stub about GDB client features, and request remote target features.
1411 The first feature implemented is PacketSize, which allows the target to
1412 specify the size of packets it can handle - to minimize the number of
1413 packets required and improve performance when connected to a remote
1417 Fetch an OS auxilliary vector from the remote stub. This packet is a
1418 more efficient replacement for qPart:auxv:read.
1420 qXfer:memory-map:read:
1421 Fetch a memory map from the remote stub, including information about
1422 RAM, ROM, and flash memory devices.
1427 Erase and program a flash memory device.
1429 * Removed remote packets
1432 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1433 used it, and only gdbserver implemented it.
1435 *** Changes in GDB 6.5
1439 Renesas M32C/M16C m32c-elf
1441 Morpho Technologies ms1 ms1-elf
1445 init-if-undefined Initialize a convenience variable, but
1446 only if it doesn't already have a value.
1448 The following commands are presently only implemented for native GNU/Linux:
1450 checkpoint Save a snapshot of the program state.
1452 restart <n> Return the program state to a
1453 previously saved state.
1455 info checkpoints List currently saved checkpoints.
1457 delete-checkpoint <n> Delete a previously saved checkpoint.
1459 set|show detach-on-fork Tell gdb whether to detach from a newly
1460 forked process, or to keep debugging it.
1462 info forks List forks of the user program that
1463 are available to be debugged.
1465 fork <n> Switch to debugging one of several
1466 forks of the user program that are
1467 available to be debugged.
1469 delete-fork <n> Delete a fork from the list of forks
1470 that are available to be debugged (and
1471 kill the forked process).
1473 detach-fork <n> Delete a fork from the list of forks
1474 that are available to be debugged (and
1475 allow the process to continue).
1479 Morpho Technologies ms2 ms1-elf
1481 * Improved Windows host support
1483 GDB now builds as a cross debugger hosted on i686-mingw32, including
1484 native console support, and remote communications using either
1485 network sockets or serial ports.
1487 * Improved Modula-2 language support
1489 GDB can now print most types in the Modula-2 syntax. This includes:
1490 basic types, set types, record types, enumerated types, range types,
1491 pointer types and ARRAY types. Procedure var parameters are correctly
1492 printed and hexadecimal addresses and character constants are also
1493 written in the Modula-2 syntax. Best results can be obtained by using
1494 GNU Modula-2 together with the -gdwarf-2 command line option.
1498 The ARM rdi-share module.
1500 The Netware NLM debug server.
1502 *** Changes in GDB 6.4
1504 * New native configurations
1506 OpenBSD/arm arm*-*-openbsd*
1507 OpenBSD/mips64 mips64-*-openbsd*
1511 Morpho Technologies ms1 ms1-elf
1513 * New command line options
1515 --batch-silent As for --batch, but totally silent.
1516 --return-child-result The debugger will exist with the same value
1517 the child (debugged) program exited with.
1518 --eval-command COMMAND, -ex COMMAND
1519 Execute a single GDB CLI command. This may be
1520 specified multiple times and in conjunction
1521 with the --command (-x) option.
1523 * Deprecated commands removed
1525 The following commands, that were deprecated in 2000, have been
1529 set|show arm disassembly-flavor set|show arm disassembler
1530 othernames set arm disassembler
1531 set|show remotedebug set|show debug remote
1532 set|show archdebug set|show debug arch
1533 set|show eventdebug set|show debug event
1536 * New BSD user-level threads support
1538 It is now possible to debug programs using the user-level threads
1539 library on OpenBSD and FreeBSD. Currently supported (target)
1542 FreeBSD/amd64 x86_64-*-freebsd*
1543 FreeBSD/i386 i386-*-freebsd*
1544 OpenBSD/i386 i386-*-openbsd*
1546 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1547 are not yet supported.
1549 * New support for Matsushita MN10300 w/sim added
1550 (Work in progress). mn10300-elf.
1552 * REMOVED configurations and files
1554 VxWorks and the XDR protocol *-*-vxworks
1555 Motorola MCORE mcore-*-*
1556 National Semiconductor NS32000 ns32k-*-*
1558 * New "set print array-indexes" command
1560 After turning this setting "on", GDB prints the index of each element
1561 when displaying arrays. The default is "off" to preserve the previous
1564 * VAX floating point support
1566 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1568 * User-defined command support
1570 In addition to using $arg0..$arg9 for argument passing, it is now possible
1571 to use $argc to determine now many arguments have been passed. See the
1572 section on user-defined commands in the user manual for more information.
1574 *** Changes in GDB 6.3:
1576 * New command line option
1578 GDB now accepts -l followed by a number to set the timeout for remote
1581 * GDB works with GCC -feliminate-dwarf2-dups
1583 GDB now supports a more compact representation of DWARF-2 debug
1584 information using DW_FORM_ref_addr references. These are produced
1585 by GCC with the option -feliminate-dwarf2-dups and also by some
1586 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1587 to use -feliminate-dwarf2-dups.
1589 * Internationalization
1591 When supported by the host system, GDB will be built with
1592 internationalization (libintl). The task of marking up the sources is
1593 continued, we're looking forward to our first translation.
1597 Initial support for debugging programs compiled with the GNAT
1598 implementation of the Ada programming language has been integrated
1599 into GDB. In this release, support is limited to expression evaluation.
1601 * New native configurations
1603 GNU/Linux/m32r m32r-*-linux-gnu
1607 GDB's remote protocol now includes support for the 'p' packet. This
1608 packet is used to fetch individual registers from a remote inferior.
1610 * END-OF-LIFE registers[] compatibility module
1612 GDB's internal register infrastructure has been completely rewritten.
1613 The new infrastructure making possible the implementation of key new
1614 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1617 GDB 6.3 will be the last release to include the the registers[]
1618 compatibility module that allowed out-of-date configurations to
1619 continue to work. This change directly impacts the following
1629 powerpc bdm protocol
1631 Unless there is activity to revive these configurations, they will be
1632 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1634 * OBSOLETE configurations and files
1636 Configurations that have been declared obsolete in this release have
1637 been commented out. Unless there is activity to revive these
1638 configurations, the next release of GDB will have their sources
1639 permanently REMOVED.
1648 *** Changes in GDB 6.2.1:
1650 * MIPS `break main; run' gave an heuristic-fence-post warning
1652 When attempting to run even a simple program, a warning about
1653 heuristic-fence-post being hit would be reported. This problem has
1656 * MIPS IRIX 'long double' crashed GDB
1658 When examining a long double variable, GDB would get a segmentation
1659 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1660 IRIX long double values).
1664 A bug in the VAX stack code was causing problems with the "next"
1665 command. This problem has been fixed.
1667 *** Changes in GDB 6.2:
1669 * Fix for ``many threads''
1671 On GNU/Linux systems that use the NPTL threads library, a program
1672 rapidly creating and deleting threads would confuse GDB leading to the
1675 ptrace: No such process.
1676 thread_db_get_info: cannot get thread info: generic error
1678 This problem has been fixed.
1680 * "-async" and "-noasync" options removed.
1682 Support for the broken "-noasync" option has been removed (it caused
1685 * New ``start'' command.
1687 This command runs the program until the begining of the main procedure.
1689 * New BSD Kernel Data Access Library (libkvm) interface
1691 Using ``target kvm'' it is now possible to debug kernel core dumps and
1692 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1693 platforms. Currently supported (native-only) configurations are:
1695 FreeBSD/amd64 x86_64-*-freebsd*
1696 FreeBSD/i386 i?86-*-freebsd*
1697 NetBSD/i386 i?86-*-netbsd*
1698 NetBSD/m68k m68*-*-netbsd*
1699 NetBSD/sparc sparc-*-netbsd*
1700 OpenBSD/amd64 x86_64-*-openbsd*
1701 OpenBSD/i386 i?86-*-openbsd*
1702 OpenBSD/m68k m68*-openbsd*
1703 OpenBSD/sparc sparc-*-openbsd*
1705 * Signal trampoline code overhauled
1707 Many generic problems with GDB's signal handling code have been fixed.
1708 These include: backtraces through non-contiguous stacks; recognition
1709 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1710 call; backtrace through a signal trampoline; step into and out of
1711 signal handlers; and single-stepping in the signal trampoline.
1713 Please note that kernel bugs are a limiting factor here. These
1714 features have been shown to work on an s390 GNU/Linux system that
1715 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1717 * Cygwin support for DWARF 2 added.
1719 * New native configurations
1721 GNU/Linux/hppa hppa*-*-linux*
1722 OpenBSD/hppa hppa*-*-openbsd*
1723 OpenBSD/m68k m68*-*-openbsd*
1724 OpenBSD/m88k m88*-*-openbsd*
1725 OpenBSD/powerpc powerpc-*-openbsd*
1726 NetBSD/vax vax-*-netbsd*
1727 OpenBSD/vax vax-*-openbsd*
1729 * END-OF-LIFE frame compatibility module
1731 GDB's internal frame infrastructure has been completely rewritten.
1732 The new infrastructure making it possible to support key new features
1733 including DWARF 2 Call Frame Information. To aid in the task of
1734 migrating old configurations to this new infrastructure, a
1735 compatibility module, that allowed old configurations to continue to
1736 work, was also included.
1738 GDB 6.2 will be the last release to include this frame compatibility
1739 module. This change directly impacts the following configurations:
1749 Unless there is activity to revive these configurations, they will be
1750 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1752 * REMOVED configurations and files
1754 Sun 3, running SunOS 3 m68*-*-sunos3*
1755 Sun 3, running SunOS 4 m68*-*-sunos4*
1756 Sun 2, running SunOS 3 m68000-*-sunos3*
1757 Sun 2, running SunOS 4 m68000-*-sunos4*
1758 Motorola 680x0 running LynxOS m68*-*-lynxos*
1759 AT&T 3b1/Unix pc m68*-att-*
1760 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1761 decstation mips-dec-* mips-little-*
1762 riscos mips-*-riscos* mips-*-sysv*
1763 sonymips mips-sony-*
1764 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1766 *** Changes in GDB 6.1.1:
1768 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1770 The TUI (Text-mode User Interface) is now built as part of a default
1771 GDB configuration. It is enabled by either selecting the TUI with the
1772 command line option "-i=tui" or by running the separate "gdbtui"
1773 program. For more information on the TUI, see the manual "Debugging
1776 * Pending breakpoint support (also included in GDB 6.1)
1778 Support has been added to allow you to specify breakpoints in shared
1779 libraries that have not yet been loaded. If a breakpoint location
1780 cannot be found, and the "breakpoint pending" option is set to auto,
1781 GDB queries you if you wish to make the breakpoint pending on a future
1782 shared-library load. If and when GDB resolves the breakpoint symbol,
1783 the pending breakpoint is removed as one or more regular breakpoints
1786 Pending breakpoints are very useful for GCJ Java debugging.
1788 * Fixed ISO-C build problems
1790 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1791 non ISO-C code that stopped them being built using a more strict ISO-C
1792 compiler (e.g., IBM's C compiler).
1794 * Fixed build problem on IRIX 5
1796 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1797 wasn't able to compile compile on an IRIX 5 system.
1799 * Added execute permission to gdb/gdbserver/configure
1801 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1802 permission. This bug would cause configure to fail on a number of
1803 systems (Solaris, IRIX). Ref: server/519.
1805 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1807 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1808 has been updated to use constant array sizes.
1810 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1812 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1813 its generated DWARF Call Frame Info. This encoding was causing GDB to
1814 panic, that panic has been fixed. Ref: gdb/1628.
1816 * Fixed a problem when examining parameters in shared library code.
1818 When examining parameters in optimized shared library code generated
1819 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1820 not available''. GDB now correctly displays the variable's value.
1822 *** Changes in GDB 6.1:
1824 * Removed --with-mmalloc
1826 Support for the mmalloc memory manager has been removed, as it
1827 conflicted with the internal gdb byte cache.
1829 * Changes in AMD64 configurations
1831 The AMD64 target now includes the %cs and %ss registers. As a result
1832 the AMD64 remote protocol has changed; this affects the floating-point
1833 and SSE registers. If you rely on those registers for your debugging,
1834 you should upgrade gdbserver on the remote side.
1836 * Revised SPARC target
1838 The SPARC target has been completely revised, incorporating the
1839 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1840 support for LynxOS and SunOS 4 has been dropped. Calling functions
1841 from within GDB on operating systems with a non-executable stack
1842 (Solaris, OpenBSD) now works.
1846 GDB has a new C++ demangler which does a better job on the mangled
1847 names generated by current versions of g++. It also runs faster, so
1848 with this and other changes gdb should now start faster on large C++
1851 * DWARF 2 Location Expressions
1853 GDB support for location expressions has been extended to support function
1854 arguments and frame bases. Older versions of GDB could crash when they
1857 * C++ nested types and namespaces
1859 GDB's support for nested types and namespaces in C++ has been
1860 improved, especially if you use the DWARF 2 debugging format. (This
1861 is the default for recent versions of GCC on most platforms.)
1862 Specifically, if you have a class "Inner" defined within a class or
1863 namespace "Outer", then GDB realizes that the class's name is
1864 "Outer::Inner", not simply "Inner". This should greatly reduce the
1865 frequency of complaints about not finding RTTI symbols. In addition,
1866 if you are stopped at inside of a function defined within a namespace,
1867 GDB modifies its name lookup accordingly.
1869 * New native configurations
1871 NetBSD/amd64 x86_64-*-netbsd*
1872 OpenBSD/amd64 x86_64-*-openbsd*
1873 OpenBSD/alpha alpha*-*-openbsd*
1874 OpenBSD/sparc sparc-*-openbsd*
1875 OpenBSD/sparc64 sparc64-*-openbsd*
1877 * New debugging protocols
1879 M32R with SDI protocol m32r-*-elf*
1881 * "set prompt-escape-char" command deleted.
1883 The command "set prompt-escape-char" has been deleted. This command,
1884 and its very obscure effet on GDB's prompt, was never documented,
1885 tested, nor mentioned in the NEWS file.
1887 * OBSOLETE configurations and files
1889 Configurations that have been declared obsolete in this release have
1890 been commented out. Unless there is activity to revive these
1891 configurations, the next release of GDB will have their sources
1892 permanently REMOVED.
1894 Sun 3, running SunOS 3 m68*-*-sunos3*
1895 Sun 3, running SunOS 4 m68*-*-sunos4*
1896 Sun 2, running SunOS 3 m68000-*-sunos3*
1897 Sun 2, running SunOS 4 m68000-*-sunos4*
1898 Motorola 680x0 running LynxOS m68*-*-lynxos*
1899 AT&T 3b1/Unix pc m68*-att-*
1900 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1901 decstation mips-dec-* mips-little-*
1902 riscos mips-*-riscos* mips-*-sysv*
1903 sonymips mips-sony-*
1904 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1906 * REMOVED configurations and files
1908 SGI Irix-4.x mips-sgi-irix4 or iris4
1909 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1910 Z8000 simulator z8k-zilog-none or z8ksim
1911 Matsushita MN10200 w/simulator mn10200-*-*
1912 H8/500 simulator h8500-hitachi-hms or h8500hms
1913 HP/PA running BSD hppa*-*-bsd*
1914 HP/PA running OSF/1 hppa*-*-osf*
1915 HP/PA Pro target hppa*-*-pro*
1916 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1917 386BSD i[3456]86-*-bsd*
1918 Sequent family i[3456]86-sequent-sysv4*
1919 i[3456]86-sequent-sysv*
1920 i[3456]86-sequent-bsd*
1921 SPARC running LynxOS sparc-*-lynxos*
1922 SPARC running SunOS 4 sparc-*-sunos4*
1923 Tsqware Sparclet sparclet-*-*
1924 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1926 *** Changes in GDB 6.0:
1930 Support for debugging the Objective-C programming language has been
1931 integrated into GDB.
1933 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1935 DWARF 2's Call Frame Information makes available compiler generated
1936 information that more exactly describes the program's run-time stack.
1937 By using this information, GDB is able to provide more robust stack
1940 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1941 have been updated to use a new backtrace mechanism which includes
1942 DWARF 2 CFI support.
1946 GDB's remote protocol has been extended to include support for hosted
1947 file I/O (where the remote target uses GDB's file system). See GDB's
1948 remote protocol documentation for details.
1950 * All targets using the new architecture framework.
1952 All of GDB's targets have been updated to use the new internal
1953 architecture framework. The way is now open for future GDB releases
1954 to include cross-architecture native debugging support (i386 on amd64,
1957 * GNU/Linux's Thread Local Storage (TLS)
1959 GDB now includes support for for the GNU/Linux implementation of
1960 per-thread variables.
1962 * GNU/Linux's Native POSIX Thread Library (NPTL)
1964 GDB's thread code has been updated to work with either the new
1965 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1967 * Separate debug info.
1969 GDB, in conjunction with BINUTILS, now supports a mechanism for
1970 automatically loading debug information from a separate file. Instead
1971 of shipping full debug and non-debug versions of system libraries,
1972 system integrators can now instead ship just the stripped libraries
1973 and optional debug files.
1975 * DWARF 2 Location Expressions
1977 DWARF 2 Location Expressions allow the compiler to more completely
1978 describe the location of variables (even in optimized code) to the
1981 GDB now includes preliminary support for location expressions (support
1982 for DW_OP_piece is still missing).
1986 A number of long standing bugs that caused GDB to die while starting a
1987 Java application have been fixed. GDB's Java support is now
1988 considered "useable".
1990 * GNU/Linux support for fork, vfork, and exec.
1992 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1993 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1996 * GDB supports logging output to a file
1998 There are two new commands, "set logging" and "show logging", which can be
1999 used to capture GDB's output to a file.
2001 * The meaning of "detach" has changed for gdbserver
2003 The "detach" command will now resume the application, as documented. To
2004 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2007 * d10v, m68hc11 `regs' command deprecated
2009 The `info registers' command has been updated so that it displays the
2010 registers using a format identical to the old `regs' command.
2014 A new command, "maint set profile on/off", has been added. This command can
2015 be used to enable or disable profiling while running GDB, to profile a
2016 session or a set of commands. In addition there is a new configure switch,
2017 "--enable-profiling", which will cause GDB to be compiled with profiling
2018 data, for more informative profiling results.
2020 * Default MI syntax changed to "mi2".
2022 The default MI (machine interface) syntax, enabled by the command line
2023 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2024 "mi1", can be enabled by specifying the option "-i=mi1".
2026 Support for the original "mi0" syntax (included in GDB 5.0) has been
2029 Fix for gdb/192: removed extraneous space when displaying frame level.
2030 Fix for gdb/672: update changelist is now output in mi list format.
2031 Fix for gdb/702: a -var-assign that updates the value now shows up
2032 in a subsequent -var-update.
2034 * New native configurations.
2036 FreeBSD/amd64 x86_64-*-freebsd*
2038 * Multi-arched targets.
2040 HP/PA HPUX11 hppa*-*-hpux*
2041 Renesas M32R/D w/simulator m32r-*-elf*
2043 * OBSOLETE configurations and files
2045 Configurations that have been declared obsolete in this release have
2046 been commented out. Unless there is activity to revive these
2047 configurations, the next release of GDB will have their sources
2048 permanently REMOVED.
2050 Z8000 simulator z8k-zilog-none or z8ksim
2051 Matsushita MN10200 w/simulator mn10200-*-*
2052 H8/500 simulator h8500-hitachi-hms or h8500hms
2053 HP/PA running BSD hppa*-*-bsd*
2054 HP/PA running OSF/1 hppa*-*-osf*
2055 HP/PA Pro target hppa*-*-pro*
2056 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2057 Sequent family i[3456]86-sequent-sysv4*
2058 i[3456]86-sequent-sysv*
2059 i[3456]86-sequent-bsd*
2060 Tsqware Sparclet sparclet-*-*
2061 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2063 * REMOVED configurations and files
2066 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2067 IBM AIX PS/2 i[3456]86-*-aix
2068 i386 running Mach 3.0 i[3456]86-*-mach3*
2069 i386 running Mach i[3456]86-*-mach*
2070 i386 running OSF/1 i[3456]86-*osf1mk*
2071 HP/Apollo 68k Family m68*-apollo*-sysv*,
2073 m68*-hp-bsd*, m68*-hp-hpux*
2074 Argonaut Risc Chip (ARC) arc-*-*
2075 Mitsubishi D30V d30v-*-*
2076 Fujitsu FR30 fr30-*-elf*
2077 OS/9000 i[34]86-*-os9k
2078 I960 with MON960 i960-*-coff
2080 * MIPS $fp behavior changed
2082 The convenience variable $fp, for the MIPS, now consistently returns
2083 the address of the current frame's base. Previously, depending on the
2084 context, $fp could refer to either $sp or the current frame's base
2085 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2086 The GNU Source-Level Debugger''.
2088 *** Changes in GDB 5.3:
2090 * GNU/Linux shared library multi-threaded performance improved.
2092 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2093 `/proc', in preference to `ptrace' for memory reads. This may result
2094 in an improvement in the start-up time of multi-threaded, shared
2095 library applications when run under GDB. One GDB user writes: ``loads
2096 shared libs like mad''.
2098 * ``gdbserver'' now supports multi-threaded applications on some targets
2100 Support for debugging multi-threaded applications which use
2101 the GNU/Linux LinuxThreads package has been added for
2102 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2103 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2105 * GDB now supports C/C++ preprocessor macros.
2107 GDB now expands preprocessor macro invocations in C/C++ expressions,
2108 and provides various commands for showing macro definitions and how
2111 The new command `macro expand EXPRESSION' expands any macro
2112 invocations in expression, and shows the result.
2114 The new command `show macro MACRO-NAME' shows the definition of the
2115 macro named MACRO-NAME, and where it was defined.
2117 Most compilers don't include information about macros in the debugging
2118 information by default. In GCC 3.1, for example, you need to compile
2119 your program with the options `-gdwarf-2 -g3'. If the macro
2120 information is present in the executable, GDB will read it.
2122 * Multi-arched targets.
2124 DEC Alpha (partial) alpha*-*-*
2125 DEC VAX (partial) vax-*-*
2127 National Semiconductor NS32000 (partial) ns32k-*-*
2128 Motorola 68000 (partial) m68k-*-*
2129 Motorola MCORE mcore-*-*
2133 Fujitsu FRV architecture added by Red Hat frv*-*-*
2136 * New native configurations
2138 Alpha NetBSD alpha*-*-netbsd*
2139 SH NetBSD sh*-*-netbsdelf*
2140 MIPS NetBSD mips*-*-netbsd*
2141 UltraSPARC NetBSD sparc64-*-netbsd*
2143 * OBSOLETE configurations and files
2145 Configurations that have been declared obsolete in this release have
2146 been commented out. Unless there is activity to revive these
2147 configurations, the next release of GDB will have their sources
2148 permanently REMOVED.
2150 Mitsubishi D30V d30v-*-*
2151 OS/9000 i[34]86-*-os9k
2152 IBM AIX PS/2 i[3456]86-*-aix
2153 Fujitsu FR30 fr30-*-elf*
2154 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2155 Argonaut Risc Chip (ARC) arc-*-*
2156 i386 running Mach 3.0 i[3456]86-*-mach3*
2157 i386 running Mach i[3456]86-*-mach*
2158 i386 running OSF/1 i[3456]86-*osf1mk*
2159 HP/Apollo 68k Family m68*-apollo*-sysv*,
2161 m68*-hp-bsd*, m68*-hp-hpux*
2162 I960 with MON960 i960-*-coff
2164 * OBSOLETE languages
2166 CHILL, a Pascal like language used by telecommunications companies.
2168 * REMOVED configurations and files
2170 AMD 29k family via UDI a29k-amd-udi, udi29k
2171 A29K VxWorks a29k-*-vxworks
2172 AMD 29000 embedded, using EBMON a29k-none-none
2173 AMD 29000 embedded with COFF a29k-none-coff
2174 AMD 29000 embedded with a.out a29k-none-aout
2176 testsuite/gdb.hp/gdb.threads-hp/ directory
2178 * New command "set max-user-call-depth <nnn>"
2180 This command allows the user to limit the call depth of user-defined
2181 commands. The default is 1024.
2183 * Changes in FreeBSD/i386 native debugging.
2185 Support for the "generate-core-file" has been added.
2187 * New commands "dump", "append", and "restore".
2189 These commands allow data to be copied from target memory
2190 to a bfd-format or binary file (dump and append), and back
2191 from a file into memory (restore).
2193 * Improved "next/step" support on multi-processor Alpha Tru64.
2195 The previous single-step mechanism could cause unpredictable problems,
2196 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2197 of a software single-step mechanism prevents this.
2199 *** Changes in GDB 5.2.1:
2207 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2208 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2209 Fix, by Joel Brobecker imported from mainline.
2211 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2212 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2213 Fix, by Fred Fish, imported from mainline.
2215 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2216 Surprisingly enough, it works now.
2217 By Michal Ludvig, imported from mainline.
2219 i386 hardware watchpoint support:
2220 avoid misses on second run for some targets.
2221 By Pierre Muller, imported from mainline.
2223 *** Changes in GDB 5.2:
2225 * New command "set trust-readonly-sections on[off]".
2227 This command is a hint that tells gdb that read-only sections
2228 really are read-only (ie. that their contents will not change).
2229 In this mode, gdb will go to the object file rather than the
2230 target to read memory from read-only sections (such as ".text").
2231 This can be a significant performance improvement on some
2232 (notably embedded) targets.
2234 * New command "generate-core-file" (or "gcore").
2236 This new gdb command allows the user to drop a core file of the child
2237 process state at any time. So far it's been implemented only for
2238 GNU/Linux and Solaris, but should be relatively easily ported to other
2239 hosts. Argument is core file name (defaults to core.<pid>).
2241 * New command line option
2243 GDB now accepts --pid or -p followed by a process id.
2245 * Change in command line behavior -- corefiles vs. process ids.
2247 There is a subtle behavior in the way in which GDB handles
2248 command line arguments. The first non-flag argument is always
2249 a program to debug, but the second non-flag argument may either
2250 be a corefile or a process id. Previously, GDB would attempt to
2251 open the second argument as a corefile, and if that failed, would
2252 issue a superfluous error message and then attempt to attach it as
2253 a process. Now, if the second argument begins with a non-digit,
2254 it will be treated as a corefile. If it begins with a digit,
2255 GDB will attempt to attach it as a process, and if no such process
2256 is found, will then attempt to open it as a corefile.
2258 * Changes in ARM configurations.
2260 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2261 configuration is fully multi-arch.
2263 * New native configurations
2265 ARM NetBSD arm*-*-netbsd*
2266 x86 OpenBSD i[3456]86-*-openbsd*
2267 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2268 Sparc64 running FreeBSD sparc64-*-freebsd*
2272 Sanyo XStormy16 xstormy16-elf
2274 * OBSOLETE configurations and files
2276 Configurations that have been declared obsolete in this release have
2277 been commented out. Unless there is activity to revive these
2278 configurations, the next release of GDB will have their sources
2279 permanently REMOVED.
2281 AMD 29k family via UDI a29k-amd-udi, udi29k
2282 A29K VxWorks a29k-*-vxworks
2283 AMD 29000 embedded, using EBMON a29k-none-none
2284 AMD 29000 embedded with COFF a29k-none-coff
2285 AMD 29000 embedded with a.out a29k-none-aout
2287 testsuite/gdb.hp/gdb.threads-hp/ directory
2289 * REMOVED configurations and files
2291 TI TMS320C80 tic80-*-*
2293 PowerPC Solaris powerpcle-*-solaris*
2294 PowerPC Windows NT powerpcle-*-cygwin32
2295 PowerPC Netware powerpc-*-netware*
2296 Harris/CXUX m88k m88*-harris-cxux*
2297 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2298 ns32k-utek-sysv* ns32k-utek-*
2299 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2300 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2301 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2302 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2303 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2305 * Changes to command line processing
2307 The new `--args' feature can be used to specify command-line arguments
2308 for the inferior from gdb's command line.
2310 * Changes to key bindings
2312 There is a new `operate-and-get-next' function bound to `C-o'.
2314 *** Changes in GDB 5.1.1
2316 Fix compile problem on DJGPP.
2318 Fix a problem with floating-point registers on the i386 being
2321 Fix to stop GDB crashing on .debug_str debug info.
2323 Numerous documentation fixes.
2325 Numerous testsuite fixes.
2327 *** Changes in GDB 5.1:
2329 * New native configurations
2331 Alpha FreeBSD alpha*-*-freebsd*
2332 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2333 MIPS GNU/Linux mips*-*-linux*
2334 MIPS SGI Irix 6.x mips*-sgi-irix6*
2335 ia64 AIX ia64-*-aix*
2336 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2340 Motorola 68HC11 and 68HC12 m68hc11-elf
2342 UltraSparc running GNU/Linux sparc64-*-linux*
2344 * OBSOLETE configurations and files
2346 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2347 Harris/CXUX m88k m88*-harris-cxux*
2348 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2349 ns32k-utek-sysv* ns32k-utek-*
2350 TI TMS320C80 tic80-*-*
2352 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2353 PowerPC Solaris powerpcle-*-solaris*
2354 PowerPC Windows NT powerpcle-*-cygwin32
2355 PowerPC Netware powerpc-*-netware*
2356 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2357 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2358 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2359 Apple Macintosh (MPW) host N/A
2361 stuff.c (Program to stuff files into a specially prepared space in kdb)
2362 kdb-start.c (Main loop for the standalone kernel debugger)
2364 Configurations that have been declared obsolete in this release have
2365 been commented out. Unless there is activity to revive these
2366 configurations, the next release of GDB will have their sources
2367 permanently REMOVED.
2369 * REMOVED configurations and files
2371 Altos 3068 m68*-altos-*
2372 Convex c1-*-*, c2-*-*
2374 ARM RISCix arm-*-* (as host)
2378 * GDB has been converted to ISO C.
2380 GDB's source code has been converted to ISO C. In particular, the
2381 sources are fully protoized, and rely on standard headers being
2386 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2388 * The MI enabled by default.
2390 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2391 revised and enabled by default. Packages which use GDB as a debugging
2392 engine behind a UI or another front end are encouraged to switch to
2393 using the GDB/MI interface, instead of the old annotations interface
2394 which is now deprecated.
2396 * Support for debugging Pascal programs.
2398 GDB now includes support for debugging Pascal programs. The following
2399 main features are supported:
2401 - Pascal-specific data types such as sets;
2403 - automatic recognition of Pascal sources based on file-name
2406 - Pascal-style display of data types, variables, and functions;
2408 - a Pascal expression parser.
2410 However, some important features are not yet supported.
2412 - Pascal string operations are not supported at all;
2414 - there are some problems with boolean types;
2416 - Pascal type hexadecimal constants are not supported
2417 because they conflict with the internal variables format;
2419 - support for Pascal objects and classes is not full yet;
2421 - unlike Pascal, GDB is case-sensitive for symbol names.
2423 * Changes in completion.
2425 Commands such as `shell', `run' and `set args', which pass arguments
2426 to inferior programs, now complete on file names, similar to what
2427 users expect at the shell prompt.
2429 Commands which accept locations, such as `disassemble', `print',
2430 `breakpoint', `until', etc. now complete on filenames as well as
2431 program symbols. Thus, if you type "break foob TAB", and the source
2432 files linked into the programs include `foobar.c', that file name will
2433 be one of the candidates for completion. However, file names are not
2434 considered for completion after you typed a colon that delimits a file
2435 name from a name of a function in that file, as in "break foo.c:bar".
2437 `set demangle-style' completes on available demangling styles.
2439 * New platform-independent commands:
2441 It is now possible to define a post-hook for a command as well as a
2442 hook that runs before the command. For more details, see the
2443 documentation of `hookpost' in the GDB manual.
2445 * Changes in GNU/Linux native debugging.
2447 Support for debugging multi-threaded programs has been completely
2448 revised for all platforms except m68k and sparc. You can now debug as
2449 many threads as your system allows you to have.
2451 Attach/detach is supported for multi-threaded programs.
2453 Support for SSE registers was added for x86. This doesn't work for
2454 multi-threaded programs though.
2456 * Changes in MIPS configurations.
2458 Multi-arch support is enabled for all MIPS configurations.
2460 GDB can now be built as native debugger on SGI Irix 6.x systems for
2461 debugging n32 executables. (Debugging 64-bit executables is not yet
2464 * Unified support for hardware watchpoints in all x86 configurations.
2466 Most (if not all) native x86 configurations support hardware-assisted
2467 breakpoints and watchpoints in a unified manner. This support
2468 implements debug register sharing between watchpoints, which allows to
2469 put a virtually infinite number of watchpoints on the same address,
2470 and also supports watching regions up to 16 bytes with several debug
2473 The new maintenance command `maintenance show-debug-regs' toggles
2474 debugging print-outs in functions that insert, remove, and test
2475 watchpoints and hardware breakpoints.
2477 * Changes in the DJGPP native configuration.
2479 New command ``info dos sysinfo'' displays assorted information about
2480 the CPU, OS, memory, and DPMI server.
2482 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2483 display information about segment descriptors stored in GDT, LDT, and
2486 New commands ``info dos pde'' and ``info dos pte'' display entries
2487 from Page Directory and Page Tables (for now works with CWSDPMI only).
2488 New command ``info dos address-pte'' displays the Page Table entry for
2489 a given linear address.
2491 GDB can now pass command lines longer than 126 characters to the
2492 program being debugged (requires an update to the libdbg.a library
2493 which is part of the DJGPP development kit).
2495 DWARF2 debug info is now supported.
2497 It is now possible to `step' and `next' through calls to `longjmp'.
2499 * Changes in documentation.
2501 All GDB documentation was converted to GFDL, the GNU Free
2502 Documentation License.
2504 Tracepoints-related commands are now fully documented in the GDB
2507 TUI, the Text-mode User Interface, is now documented in the manual.
2509 Tracepoints-related commands are now fully documented in the GDB
2512 The "GDB Internals" manual now has an index. It also includes
2513 documentation of `ui_out' functions, GDB coding standards, x86
2514 hardware watchpoints, and memory region attributes.
2516 * GDB's version number moved to ``version.in''
2518 The Makefile variable VERSION has been replaced by the file
2519 ``version.in''. People creating GDB distributions should update the
2520 contents of this file.
2524 GUD support is now a standard part of the EMACS distribution.
2526 *** Changes in GDB 5.0:
2528 * Improved support for debugging FP programs on x86 targets
2530 Unified and much-improved support for debugging floating-point
2531 programs on all x86 targets. In particular, ``info float'' now
2532 displays the FP registers in the same format on all x86 targets, with
2533 greater level of detail.
2535 * Improvements and bugfixes in hardware-assisted watchpoints
2537 It is now possible to watch array elements, struct members, and
2538 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2539 on x86 targets no longer erroneously trigger when the address is
2542 * Improvements in the native DJGPP version of GDB
2544 The distribution now includes all the scripts and auxiliary files
2545 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2546 machines ``out of the box''.
2548 The DJGPP version can now debug programs that use signals. It is
2549 possible to catch signals that happened in the debuggee, deliver
2550 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2551 would kill the program being debugged.) Programs that hook hardware
2552 interrupts (keyboard, timer, etc.) can also be debugged.
2554 It is now possible to debug DJGPP programs that redirect their
2555 standard handles or switch them to raw (as opposed to cooked) mode, or
2556 even close them. The command ``run < foo > bar'' works as expected,
2557 and ``info terminal'' reports useful information about the debuggee's
2558 terminal, including raw/cooked mode, redirection, etc.
2560 The DJGPP version now uses termios functions for console I/O, which
2561 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2564 DOS-style file names with drive letters are now fully supported by
2567 It is now possible to debug DJGPP programs that switch their working
2568 directory. It is also possible to rerun the debuggee any number of
2569 times without restarting GDB; thus, you can use the same setup,
2570 breakpoints, etc. for many debugging sessions.
2572 * New native configurations
2574 ARM GNU/Linux arm*-*-linux*
2575 PowerPC GNU/Linux powerpc-*-linux*
2579 Motorola MCore mcore-*-*
2580 x86 VxWorks i[3456]86-*-vxworks*
2581 PowerPC VxWorks powerpc-*-vxworks*
2582 TI TMS320C80 tic80-*-*
2584 * OBSOLETE configurations
2586 Altos 3068 m68*-altos-*
2587 Convex c1-*-*, c2-*-*
2589 ARM RISCix arm-*-* (as host)
2592 Configurations that have been declared obsolete will be commented out,
2593 but the code will be left in place. If there is no activity to revive
2594 these configurations before the next release of GDB, the sources will
2595 be permanently REMOVED.
2597 * Gould support removed
2599 Support for the Gould PowerNode and NP1 has been removed.
2601 * New features for SVR4
2603 On SVR4 native platforms (such as Solaris), if you attach to a process
2604 without first loading a symbol file, GDB will now attempt to locate and
2605 load symbols from the running process's executable file.
2607 * Many C++ enhancements
2609 C++ support has been greatly improved. Overload resolution now works properly
2610 in almost all cases. RTTI support is on the way.
2612 * Remote targets can connect to a sub-program
2614 A popen(3) style serial-device has been added. This device starts a
2615 sub-process (such as a stand-alone simulator) and then communicates
2616 with that. The sub-program to run is specified using the syntax
2617 ``|<program> <args>'' vis:
2619 (gdb) set remotedebug 1
2620 (gdb) target extended-remote |mn10300-elf-sim program-args
2622 * MIPS 64 remote protocol
2624 A long standing bug in the mips64 remote protocol where by GDB
2625 expected certain 32 bit registers (ex SR) to be transfered as 32
2626 instead of 64 bits has been fixed.
2628 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2629 added to provide backward compatibility with older versions of GDB.
2631 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2633 The command ``set remotebinarydownload'' command has been replaced by
2634 ``set remote X-packet''. Other commands in ``set remote'' family
2635 include ``set remote P-packet''.
2637 * Breakpoint commands accept ranges.
2639 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2640 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2641 ``tracepoint passcount'' also accepts a range of tracepoints.
2643 * ``apropos'' command added.
2645 The ``apropos'' command searches through command names and
2646 documentation strings, printing out matches, making it much easier to
2647 try to find a command that does what you are looking for.
2651 A new machine oriented interface (MI) has been added to GDB. This
2652 interface is designed for debug environments running GDB as a separate
2653 process. This is part of the long term libGDB project. See the
2654 "GDB/MI" chapter of the GDB manual for further information. It can be
2655 enabled by configuring with:
2657 .../configure --enable-gdbmi
2659 *** Changes in GDB-4.18:
2661 * New native configurations
2663 HP-UX 10.20 hppa*-*-hpux10.20
2664 HP-UX 11.x hppa*-*-hpux11.0*
2665 M68K GNU/Linux m68*-*-linux*
2669 Fujitsu FR30 fr30-*-elf*
2670 Intel StrongARM strongarm-*-*
2671 Mitsubishi D30V d30v-*-*
2673 * OBSOLETE configurations
2675 Gould PowerNode, NP1 np1-*-*, pn-*-*
2677 Configurations that have been declared obsolete will be commented out,
2678 but the code will be left in place. If there is no activity to revive
2679 these configurations before the next release of GDB, the sources will
2680 be permanently REMOVED.
2684 As a compatibility experiment, GDB's source files buildsym.h and
2685 buildsym.c have been converted to pure standard C, no longer
2686 containing any K&R compatibility code. We believe that all systems in
2687 use today either come with a standard C compiler, or have a GCC port
2688 available. If this is not true, please report the affected
2689 configuration to bug-gdb@gnu.org immediately. See the README file for
2690 information about getting a standard C compiler if you don't have one
2695 GDB now uses readline 2.2.
2697 * set extension-language
2699 You can now control the mapping between filename extensions and source
2700 languages by using the `set extension-language' command. For instance,
2701 you can ask GDB to treat .c files as C++ by saying
2702 set extension-language .c c++
2703 The command `info extensions' lists all of the recognized extensions
2704 and their associated languages.
2706 * Setting processor type for PowerPC and RS/6000
2708 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2709 you can use the `set processor' command to specify what variant of the
2710 PowerPC family you are debugging. The command
2714 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2715 following PowerPC and RS6000 variants:
2717 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2718 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2720 403GC IBM PowerPC 403GC
2721 505 Motorola PowerPC 505
2722 860 Motorola PowerPC 860 or 850
2723 601 Motorola PowerPC 601
2724 602 Motorola PowerPC 602
2725 603 Motorola/IBM PowerPC 603 or 603e
2726 604 Motorola PowerPC 604 or 604e
2727 750 Motorola/IBM PowerPC 750 or 750
2729 At the moment, this command just tells GDB what to name the
2730 special-purpose processor registers. Since almost all the affected
2731 registers are inaccessible to user-level programs, this command is
2732 only useful for remote debugging in its present form.
2736 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2737 more extensive support for HP-UX. Added features include shared
2738 library support, kernel threads and hardware watchpoints for 11.00,
2739 support for HP's ANSI C and C++ compilers, and a compatibility mode
2740 for xdb and dbx commands.
2744 HP's donation includes the new concept of catchpoints, which is a
2745 generalization of the old catch command. On HP-UX, it is now possible
2746 to catch exec, fork, and vfork, as well as library loading.
2748 This means that the existing catch command has changed; its first
2749 argument now specifies the type of catch to be set up. See the
2750 output of "help catch" for a list of catchpoint types.
2752 * Debugging across forks
2754 On HP-UX, you can choose which process to debug when a fork() happens
2759 HP has donated a curses-based terminal user interface (TUI). To get
2760 it, build with --enable-tui. Although this can be enabled for any
2761 configuration, at present it only works for native HP debugging.
2763 * GDB remote protocol additions
2765 A new protocol packet 'X' that writes binary data is now available.
2766 Default behavior is to try 'X', then drop back to 'M' if the stub
2767 fails to respond. The settable variable `remotebinarydownload'
2768 allows explicit control over the use of 'X'.
2770 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2771 full 64-bit address. The command
2773 set remoteaddresssize 32
2775 can be used to revert to the old behaviour. For existing remote stubs
2776 the change should not be noticed, as the additional address information
2779 In order to assist in debugging stubs, you may use the maintenance
2780 command `packet' to send any text string to the stub. For instance,
2782 maint packet heythere
2784 sends the packet "$heythere#<checksum>". Note that it is very easy to
2785 disrupt a debugging session by sending the wrong packet at the wrong
2788 The compare-sections command allows you to compare section data on the
2789 target to what is in the executable file without uploading or
2790 downloading, by comparing CRC checksums.
2792 * Tracing can collect general expressions
2794 You may now collect general expressions at tracepoints. This requires
2795 further additions to the target-side stub; see tracepoint.c and
2796 doc/agentexpr.texi for further details.
2798 * mask-address variable for Mips
2800 For Mips targets, you may control the zeroing of the upper 32 bits of
2801 a 64-bit address by entering `set mask-address on'. This is mainly
2802 of interest to users of embedded R4xxx and R5xxx processors.
2804 * Higher serial baud rates
2806 GDB's serial code now allows you to specify baud rates 57600, 115200,
2807 230400, and 460800 baud. (Note that your host system may not be able
2808 to achieve all of these rates.)
2812 The i960 configuration now includes an initial implementation of a
2813 builtin simulator, contributed by Jim Wilson.
2816 *** Changes in GDB-4.17:
2818 * New native configurations
2820 Alpha GNU/Linux alpha*-*-linux*
2821 Unixware 2.x i[3456]86-unixware2*
2822 Irix 6.x mips*-sgi-irix6*
2823 PowerPC GNU/Linux powerpc-*-linux*
2824 PowerPC Solaris powerpcle-*-solaris*
2825 Sparc GNU/Linux sparc-*-linux*
2826 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2830 Argonaut Risc Chip (ARC) arc-*-*
2831 Hitachi H8/300S h8300*-*-*
2832 Matsushita MN10200 w/simulator mn10200-*-*
2833 Matsushita MN10300 w/simulator mn10300-*-*
2834 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2835 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2836 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2837 Mitsubishi D10V w/simulator d10v-*-*
2838 Mitsubishi M32R/D w/simulator m32r-*-elf*
2839 Tsqware Sparclet sparclet-*-*
2840 NEC V850 w/simulator v850-*-*
2842 * New debugging protocols
2844 ARM with RDI protocol arm*-*-*
2845 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2846 DDB and LSI variants of PMON protocol mips*-*-*
2847 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2848 PowerPC with SDS protocol powerpc{,le}-*-eabi
2849 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2853 All configurations can now understand and use the DWARF 2 debugging
2854 format. The choice is automatic, if the symbol file contains DWARF 2
2859 GDB now includes basic Java language support. This support is
2860 only useful with Java compilers that produce native machine code.
2862 * solib-absolute-prefix and solib-search-path
2864 For SunOS and SVR4 shared libraries, you may now set the prefix for
2865 loading absolute shared library symbol files, and the search path for
2866 locating non-absolute shared library symbol files.
2868 * Live range splitting
2870 GDB can now effectively debug code for which GCC has performed live
2871 range splitting as part of its optimization. See gdb/doc/LRS for
2872 more details on the expected format of the stabs information.
2876 GDB's support for the GNU Hurd, including thread debugging, has been
2877 updated to work with current versions of the Hurd.
2881 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2882 instruction set. ARM GDB automatically detects when Thumb
2883 instructions are in use, and adjusts disassembly and backtracing
2888 GDB's MIPS target configurations now handle the MIP16 16-bit
2893 GDB now includes support for overlays; if an executable has been
2894 linked such that multiple sections are based at the same address, GDB
2895 will decide which section to use for symbolic info. You can choose to
2896 control the decision manually, using overlay commands, or implement
2897 additional target-side support and use "overlay load-target" to bring
2898 in the overlay mapping. Do "help overlay" for more detail.
2902 The command "info symbol <address>" displays information about
2903 the symbol at the specified address.
2907 The standard remote protocol now includes an extension that allows
2908 asynchronous collection and display of trace data. This requires
2909 extensive support in the target-side debugging stub. Tracing mode
2910 includes a new interaction mode in GDB and new commands: see the
2911 file tracepoint.c for more details.
2915 Configurations for embedded MIPS now include a simulator contributed
2916 by Cygnus Solutions. The simulator supports the instruction sets
2917 of most MIPS variants.
2921 Sparc configurations may now include the ERC32 simulator contributed
2922 by the European Space Agency. The simulator is not built into
2923 Sparc targets by default; configure with --enable-sim to include it.
2927 For target configurations that may include multiple variants of a
2928 basic architecture (such as MIPS and SH), you may now set the
2929 architecture explicitly. "set arch" sets, "info arch" lists
2930 the possible architectures.
2932 *** Changes in GDB-4.16:
2934 * New native configurations
2936 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2937 M68K NetBSD m68k-*-netbsd*
2938 PowerPC AIX 4.x powerpc-*-aix*
2939 PowerPC MacOS powerpc-*-macos*
2940 PowerPC Windows NT powerpcle-*-cygwin32
2941 RS/6000 AIX 4.x rs6000-*-aix4*
2945 ARM with RDP protocol arm-*-*
2946 I960 with MON960 i960-*-coff
2947 MIPS VxWorks mips*-*-vxworks*
2948 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2949 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2951 Matra Sparclet sparclet-*-*
2955 The powerpc-eabi configuration now includes the PSIM simulator,
2956 contributed by Andrew Cagney, with assistance from Mike Meissner.
2957 PSIM is a very elaborate model of the PowerPC, including not only
2958 basic instruction set execution, but also details of execution unit
2959 performance and I/O hardware. See sim/ppc/README for more details.
2963 GDB now works with Solaris 2.5.
2965 * Windows 95/NT native
2967 GDB will now work as a native debugger on Windows 95 and Windows NT.
2968 To build it from source, you must use the "gnu-win32" environment,
2969 which uses a DLL to emulate enough of Unix to run the GNU tools.
2970 Further information, binaries, and sources are available at
2971 ftp.cygnus.com, under pub/gnu-win32.
2973 * dont-repeat command
2975 If a user-defined command includes the command `dont-repeat', then the
2976 command will not be repeated if the user just types return. This is
2977 useful if the command is time-consuming to run, so that accidental
2978 extra keystrokes don't run the same command many times.
2980 * Send break instead of ^C
2982 The standard remote protocol now includes an option to send a break
2983 rather than a ^C to the target in order to interrupt it. By default,
2984 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2986 * Remote protocol timeout
2988 The standard remote protocol includes a new variable `remotetimeout'
2989 that allows you to set the number of seconds before GDB gives up trying
2990 to read from the target. The default value is 2.
2992 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2994 By default GDB will automatically keep track of objects as they are
2995 loaded and unloaded by the dynamic linker. By using the command `set
2996 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2997 when shared library events occur, thus allowing you to set breakpoints
2998 in shared libraries which are explicitly loaded by the inferior.
3000 Note this feature does not work on hpux8. On hpux9 you must link
3001 /usr/lib/end.o into your program. This feature should work
3002 automatically on hpux10.
3004 * Irix 5.x hardware watchpoint support
3006 Irix 5 configurations now support the use of hardware watchpoints.
3008 * Mips protocol "SYN garbage limit"
3010 When debugging a Mips target using the `target mips' protocol, you
3011 may set the number of characters that GDB will ignore by setting
3012 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3013 every character. The default value is 1050.
3015 * Recording and replaying remote debug sessions
3017 If you set `remotelogfile' to the name of a file, gdb will write to it
3018 a recording of a remote debug session. This recording may then be
3019 replayed back to gdb using "gdbreplay". See gdbserver/README for
3020 details. This is useful when you have a problem with GDB while doing
3021 remote debugging; you can make a recording of the session and send it
3022 to someone else, who can then recreate the problem.
3024 * Speedups for remote debugging
3026 GDB includes speedups for downloading and stepping MIPS systems using
3027 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3028 and more efficient S-record downloading.
3030 * Memory use reductions and statistics collection
3032 GDB now uses less memory and reports statistics about memory usage.
3033 Try the `maint print statistics' command, for example.
3035 *** Changes in GDB-4.15:
3037 * Psymtabs for XCOFF
3039 The symbol reader for AIX GDB now uses partial symbol tables. This
3040 can greatly improve startup time, especially for large executables.
3042 * Remote targets use caching
3044 Remote targets now use a data cache to speed up communication with the
3045 remote side. The data cache could lead to incorrect results because
3046 it doesn't know about volatile variables, thus making it impossible to
3047 debug targets which use memory mapped I/O devices. `set remotecache
3048 off' turns the the data cache off.
3050 * Remote targets may have threads
3052 The standard remote protocol now includes support for multiple threads
3053 in the target system, using new protocol commands 'H' and 'T'. See
3054 gdb/remote.c for details.
3058 If GDB is configured with `--enable-netrom', then it will include
3059 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3060 acts as though it is a bank of ROM on the target board, but you can
3061 write into it over the network. GDB's support consists only of
3062 support for fast loading into the emulated ROM; to debug, you must use
3063 another protocol, such as standard remote protocol. The usual
3064 sequence is something like
3066 target nrom <netrom-hostname>
3068 target remote <netrom-hostname>:1235
3072 GDB now includes support for the Apple Macintosh, as a host only. It
3073 may be run as either an MPW tool or as a standalone application, and
3074 it can debug through the serial port. All the usual GDB commands are
3075 available, but to the target command, you must supply "serial" as the
3076 device type instead of "/dev/ttyXX". See mpw-README in the main
3077 directory for more information on how to build. The MPW configuration
3078 scripts */mpw-config.in support only a few targets, and only the
3079 mips-idt-ecoff target has been tested.
3083 GDB configuration now uses autoconf. This is not user-visible,
3084 but does simplify configuration and building.
3088 GDB now supports hpux10.
3090 *** Changes in GDB-4.14:
3092 * New native configurations
3094 x86 FreeBSD i[345]86-*-freebsd
3095 x86 NetBSD i[345]86-*-netbsd
3096 NS32k NetBSD ns32k-*-netbsd
3097 Sparc NetBSD sparc-*-netbsd
3101 A29K VxWorks a29k-*-vxworks
3102 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3103 CPU32 EST-300 emulator m68*-*-est*
3104 PowerPC ELF powerpc-*-elf
3107 * Alpha OSF/1 support for procfs
3109 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3110 possible to attach to running processes. As the mounting of the /proc
3111 filesystem is optional on the Alpha, GDB automatically determines
3112 the availability of /proc during startup. This can lead to problems
3113 if /proc is unmounted after GDB has been started.
3115 * Arguments to user-defined commands
3117 User commands may accept up to 10 arguments separated by whitespace.
3118 Arguments are accessed within the user command via $arg0..$arg9. A
3121 print $arg0 + $arg1 + $arg2
3123 To execute the command use:
3126 Defines the command "adder" which prints the sum of its three arguments.
3127 Note the arguments are text substitutions, so they may reference variables,
3128 use complex expressions, or even perform inferior function calls.
3130 * New `if' and `while' commands
3132 This makes it possible to write more sophisticated user-defined
3133 commands. Both commands take a single argument, which is the
3134 expression to evaluate, and must be followed by the commands to
3135 execute, one per line, if the expression is nonzero, the list being
3136 terminated by the word `end'. The `if' command list may include an
3137 `else' word, which causes the following commands to be executed only
3138 if the expression is zero.
3140 * Fortran source language mode
3142 GDB now includes partial support for Fortran 77. It will recognize
3143 Fortran programs and can evaluate a subset of Fortran expressions, but
3144 variables and functions may not be handled correctly. GDB will work
3145 with G77, but does not yet know much about symbols emitted by other
3148 * Better HPUX support
3150 Most debugging facilities now work on dynamic executables for HPPAs
3151 running hpux9 or later. You can attach to running dynamically linked
3152 processes, but by default the dynamic libraries will be read-only, so
3153 for instance you won't be able to put breakpoints in them. To change
3154 that behavior do the following before running the program:
3160 This will cause the libraries to be mapped private and read-write.
3161 To revert to the normal behavior, do this:
3167 You cannot set breakpoints or examine data in the library until after
3168 the library is loaded if the function/data symbols do not have
3171 GDB can now also read debug symbols produced by the HP C compiler on
3172 HPPAs (sorry, no C++, Fortran or 68k support).
3174 * Target byte order now dynamically selectable
3176 You can choose which byte order to use with a target system, via the
3177 commands "set endian big" and "set endian little", and you can see the
3178 current setting by using "show endian". You can also give the command
3179 "set endian auto", in which case GDB will use the byte order
3180 associated with the executable. Currently, only embedded MIPS
3181 configurations support dynamic selection of target byte order.
3183 * New DOS host serial code
3185 This version uses DPMI interrupts to handle buffered I/O, so you
3186 no longer need to run asynctsr when debugging boards connected to
3189 *** Changes in GDB-4.13:
3191 * New "complete" command
3193 This lists all the possible completions for the rest of the line, if it
3194 were to be given as a command itself. This is intended for use by emacs.
3196 * Trailing space optional in prompt
3198 "set prompt" no longer adds a space for you after the prompt you set. This
3199 allows you to set a prompt which ends in a space or one that does not.
3201 * Breakpoint hit counts
3203 "info break" now displays a count of the number of times the breakpoint
3204 has been hit. This is especially useful in conjunction with "ignore"; you
3205 can ignore a large number of breakpoint hits, look at the breakpoint info
3206 to see how many times the breakpoint was hit, then run again, ignoring one
3207 less than that number, and this will get you quickly to the last hit of
3210 * Ability to stop printing at NULL character
3212 "set print null-stop" will cause GDB to stop printing the characters of
3213 an array when the first NULL is encountered. This is useful when large
3214 arrays actually contain only short strings.
3216 * Shared library breakpoints
3218 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3219 breakpoints in shared libraries before the executable is run.
3221 * Hardware watchpoints
3223 There is a new hardware breakpoint for the watch command for sparclite
3224 targets. See gdb/sparclite/hw_breakpoint.note.
3226 Hardware watchpoints are also now supported under GNU/Linux.
3230 Annotations have been added. These are for use with graphical interfaces,
3231 and are still experimental. Currently only gdba.el uses these.
3233 * Improved Irix 5 support
3235 GDB now works properly with Irix 5.2.
3237 * Improved HPPA support
3239 GDB now works properly with the latest GCC and GAS.
3241 * New native configurations
3243 Sequent PTX4 i[34]86-sequent-ptx4
3244 HPPA running OSF/1 hppa*-*-osf*
3245 Atari TT running SVR4 m68*-*-sysv4*
3246 RS/6000 LynxOS rs6000-*-lynxos*
3250 OS/9000 i[34]86-*-os9k
3251 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3254 * Hitachi SH7000 and E7000-PC ICE support
3256 There is now support for communicating with the Hitachi E7000-PC ICE.
3257 This is available automatically when GDB is configured for the SH.
3261 As usual, a variety of small fixes and improvements, both generic
3262 and configuration-specific. See the ChangeLog for more detail.
3264 *** Changes in GDB-4.12:
3266 * Irix 5 is now supported
3270 GDB-4.12 on the HPPA has a number of changes which make it unable
3271 to debug the output from the currently released versions of GCC and
3272 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3273 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3274 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3277 *** Changes in GDB-4.11:
3279 * User visible changes:
3283 The "set remotedebug" option is now consistent between the mips remote
3284 target, remote targets using the gdb-specific protocol, UDI (AMD's
3285 debug protocol for the 29k) and the 88k bug monitor. It is now an
3286 integer specifying a debug level (normally 0 or 1, but 2 means more
3287 debugging info for the mips target).
3289 * DEC Alpha native support
3291 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3292 debug info, but GDB works fairly well with the DEC compiler and should
3293 work with a future GCC release. See the README file for a few
3294 Alpha-specific notes.
3296 * Preliminary thread implementation
3298 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3300 * LynxOS native and target support for 386
3302 This release has been hosted on LynxOS 2.2, and also can be configured
3303 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3306 * Improvements in C++ mangling/demangling.
3308 This release has much better g++ debugging, specifically in name
3309 mangling/demangling, virtual function calls, print virtual table,
3310 call methods, ...etc.
3312 *** Changes in GDB-4.10:
3314 * User visible changes:
3316 Remote debugging using the GDB-specific (`target remote') protocol now
3317 supports the `load' command. This is only useful if you have some
3318 other way of getting the stub to the target system, and you can put it
3319 somewhere in memory where it won't get clobbered by the download.
3321 Filename completion now works.
3323 When run under emacs mode, the "info line" command now causes the
3324 arrow to point to the line specified. Also, "info line" prints
3325 addresses in symbolic form (as well as hex).
3327 All vxworks based targets now support a user settable option, called
3328 vxworks-timeout. This option represents the number of seconds gdb
3329 should wait for responses to rpc's. You might want to use this if
3330 your vxworks target is, perhaps, a slow software simulator or happens
3331 to be on the far side of a thin network line.
3335 This release contains support for using a DEC alpha as a GDB host for
3336 cross debugging. Native alpha debugging is not supported yet.
3339 *** Changes in GDB-4.9:
3343 This is the first GDB release which is accompanied by a matching testsuite.
3344 The testsuite requires installation of dejagnu, which should be available
3345 via ftp from most sites that carry GNU software.
3349 'Cfront' style demangling has had its name changed to 'ARM' style, to
3350 emphasize that it was written from the specifications in the C++ Annotated
3351 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3352 disclaimers, it still generated too much confusion with users attempting to
3353 use gdb with AT&T cfront.
3357 GDB now uses a standard remote interface to a simulator library.
3358 So far, the library contains simulators for the Zilog Z8001/2, the
3359 Hitachi H8/300, H8/500 and Super-H.
3361 * New targets supported
3363 H8/300 simulator h8300-hitachi-hms or h8300hms
3364 H8/500 simulator h8500-hitachi-hms or h8500hms
3365 SH simulator sh-hitachi-hms or sh
3366 Z8000 simulator z8k-zilog-none or z8ksim
3367 IDT MIPS board over serial line mips-idt-ecoff
3369 Cross-debugging to GO32 targets is supported. It requires a custom
3370 version of the i386-stub.c module which is integrated with the
3371 GO32 memory extender.
3373 * New remote protocols
3375 MIPS remote debugging protocol.
3377 * New source languages supported
3379 This version includes preliminary support for Chill, a Pascal like language
3380 used by telecommunications companies. Chill support is also being integrated
3381 into the GNU compiler, but we don't know when it will be publically available.
3384 *** Changes in GDB-4.8:
3386 * HP Precision Architecture supported
3388 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3389 version of this support was available as a set of patches from the
3390 University of Utah. GDB does not support debugging of programs
3391 compiled with the HP compiler, because HP will not document their file
3392 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3393 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3395 Many problems in the preliminary version have been fixed.
3397 * Faster and better demangling
3399 We have improved template demangling and fixed numerous bugs in the GNU style
3400 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3401 character types (wchar_t) are now supported. Demangling of each symbol is now
3402 only done once, and is cached when the symbol table for a file is read in.
3403 This results in a small increase in memory usage for C programs, a moderate
3404 increase in memory usage for C++ programs, and a fantastic speedup in
3407 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3408 from the specifications in the Annotated Reference Manual, which AT&T's
3409 compiler does not actually implement.
3411 * G++ multiple inheritance compiler problem
3413 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3414 inheritance lattices was reworked to properly discover ambiguities. We
3415 recently found an example which causes this new algorithm to fail in a
3416 very subtle way, producing bad debug information for those classes.
3417 The file 'gcc.patch' (in this directory) can be applied to gcc to
3418 circumvent the problem. A future GCC release will contain a complete
3421 The previous G++ debug info problem (mentioned below for the gdb-4.7
3422 release) is fixed in gcc version 2.3.2.
3424 * Improved configure script
3426 The `configure' script will now attempt to guess your system type if
3427 you don't supply a host system type. The old scheme of supplying a
3428 host system triplet is preferable over using this. All the magic is
3429 done in the new `config.guess' script. Examine it for details.
3431 We have also brought our configure script much more in line with the FSF's
3432 version. It now supports the --with-xxx options. In particular,
3433 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3434 The resulting GDB will not be able to read arbitrary object file formats --
3435 only the format ``expected'' to be used on the configured target system.
3436 We hope to make this the default in a future release.
3438 * Documentation improvements
3440 There's new internal documentation on how to modify GDB, and how to
3441 produce clean changes to the code. We implore people to read it
3442 before submitting changes.
3444 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3445 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3446 `info' files are also provided. To build `info' files from scratch,
3447 you will need the latest `makeinfo' release, which will be available in
3448 a future texinfo-X.Y release.
3450 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3451 We're not sure exactly which versions have this problem, but it has
3452 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3453 or better. If that isn't possible, there is a patch in
3454 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3455 around this problem.
3459 GDB now supports array constants that can be used in expressions typed in by
3460 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3461 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3464 The new directory `gdb/sparclite' contains a program that demonstrates
3465 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3467 * New native hosts supported
3469 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3470 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3472 * New targets supported
3474 AMD 29k family via UDI a29k-amd-udi or udi29k
3476 * New file formats supported
3478 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3479 HPUX core files, and SCO 3.2v2 core files.
3483 Attaching to processes now works again; thanks for the many bug reports.
3485 We have also stomped on a bunch of core dumps caused by
3486 printf_filtered("%s") problems.
3488 We eliminated a copyright problem on the rpc and ptrace header files
3489 for VxWorks, which was discovered at the last minute during the 4.7
3490 release. You should now be able to build a VxWorks GDB.
3492 You can now interrupt gdb while an attached process is running. This
3493 will cause the attached process to stop, and give control back to GDB.
3495 We fixed problems caused by using too many file descriptors
3496 for reading symbols from object files and libraries. This was
3497 especially a problem for programs that used many (~100) shared
3500 The `step' command now only enters a subroutine if there is line number
3501 information for the subroutine. Otherwise it acts like the `next'
3502 command. Previously, `step' would enter subroutines if there was
3503 any debugging information about the routine. This avoids problems
3504 when using `cc -g1' on MIPS machines.
3506 * Internal improvements
3508 GDB's internal interfaces have been improved to make it easier to support
3509 debugging of multiple languages in the future.
3511 GDB now uses a common structure for symbol information internally.
3512 Minimal symbols (derived from linkage symbols in object files), partial
3513 symbols (from a quick scan of debug information), and full symbols
3514 contain a common subset of information, making it easier to write
3515 shared code that handles any of them.
3517 * New command line options
3519 We now accept --silent as an alias for --quiet.
3523 The memory-mapped-malloc library is now licensed under the GNU Library
3524 General Public License.
3526 *** Changes in GDB-4.7:
3528 * Host/native/target split
3530 GDB has had some major internal surgery to untangle the support for
3531 hosts and remote targets. Now, when you configure GDB for a remote
3532 target, it will no longer load in all of the support for debugging
3533 local programs on the host. When fully completed and tested, this will
3534 ensure that arbitrary host/target combinations are possible.
3536 The primary conceptual shift is to separate the non-portable code in
3537 GDB into three categories. Host specific code is required any time GDB
3538 is compiled on that host, regardless of the target. Target specific
3539 code relates to the peculiarities of the target, but can be compiled on
3540 any host. Native specific code is everything else: it can only be
3541 built when the host and target are the same system. Child process
3542 handling and core file support are two common `native' examples.
3544 GDB's use of /proc for controlling Unix child processes is now cleaner.
3545 It has been split out into a single module under the `target_ops' vector,
3546 plus two native-dependent functions for each system that uses /proc.
3548 * New hosts supported
3550 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3551 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3552 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3554 * New targets supported
3556 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3557 68030 and CPU32 m68030-*-*, m68332-*-*
3559 * New native hosts supported
3561 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3562 (386bsd is not well tested yet)
3563 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3565 * New file formats supported
3567 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3568 supports reading of `a.out.adobe' object files, which are an a.out
3569 format extended with minimal information about multiple sections.
3573 `show copying' is the same as the old `info copying'.
3574 `show warranty' is the same as `info warrantee'.
3575 These were renamed for consistency. The old commands continue to work.
3577 `info handle' is a new alias for `info signals'.
3579 You can now define pre-command hooks, which attach arbitrary command
3580 scripts to any command. The commands in the hook will be executed
3581 prior to the user's command. You can also create a hook which will be
3582 executed whenever the program stops. See gdb.texinfo.
3586 We now deal with Cfront style name mangling, and can even extract type
3587 info from mangled symbols. GDB can automatically figure out which
3588 symbol mangling style your C++ compiler uses.
3590 Calling of methods and virtual functions has been improved as well.
3594 The crash that occured when debugging Sun Ansi-C compiled binaries is
3595 fixed. This was due to mishandling of the extra N_SO stabs output
3598 We also finally got Ultrix 4.2 running in house, and fixed core file
3599 support, with help from a dozen people on the net.
3601 John M. Farrell discovered that the reason that single-stepping was so
3602 slow on all of the Mips based platforms (primarily SGI and DEC) was
3603 that we were trying to demangle and lookup a symbol used for internal
3604 purposes on every instruction that was being stepped through. Changing
3605 the name of that symbol so that it couldn't be mistaken for a C++
3606 mangled symbol sped things up a great deal.
3608 Rich Pixley sped up symbol lookups in general by getting much smarter
3609 about when C++ symbol mangling is necessary. This should make symbol
3610 completion (TAB on the command line) much faster. It's not as fast as
3611 we'd like, but it's significantly faster than gdb-4.6.
3615 A new user controllable variable 'call_scratch_address' can
3616 specify the location of a scratch area to be used when GDB
3617 calls a function in the target. This is necessary because the
3618 usual method of putting the scratch area on the stack does not work
3619 in systems that have separate instruction and data spaces.
3621 We integrated changes to support the 29k UDI (Universal Debugger
3622 Interface), but discovered at the last minute that we didn't have all
3623 of the appropriate copyright paperwork. We are working with AMD to
3624 resolve this, and hope to have it available soon.
3628 We have sped up the remote serial line protocol, especially for targets
3629 with lots of registers. It now supports a new `expedited status' ('T')
3630 message which can be used in place of the existing 'S' status message.
3631 This allows the remote stub to send only the registers that GDB
3632 needs to make a quick decision about single-stepping or conditional
3633 breakpoints, eliminating the need to fetch the entire register set for
3634 each instruction being stepped through.
3636 The GDB remote serial protocol now implements a write-through cache for
3637 registers, only re-reading the registers if the target has run.
3639 There is also a new remote serial stub for SPARC processors. You can
3640 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3641 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3642 processor with a serial port.
3646 Configure.in files have become much easier to read and modify. A new
3647 `table driven' format makes it more obvious what configurations are
3648 supported, and what files each one uses.
3652 There is a new opcodes library which will eventually contain all of the
3653 disassembly routines and opcode tables. At present, it only contains
3654 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3655 disassembler (binutils/objdump) to share these routines.
3657 The libiberty library is now copylefted under the GNU Library General
3658 Public License. This allows more liberal use, and was done so libg++
3659 can use it. This makes no difference to GDB, since the Library License
3660 grants all the rights from the General Public License.
3664 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3665 reference to the stabs symbol info used by the debugger. It is (as far
3666 as we know) the only published document on this fascinating topic. We
3667 encourage you to read it, compare it to the stabs information on your
3668 system, and send improvements on the document in general (to
3669 bug-gdb@prep.ai.mit.edu).
3671 And, of course, many bugs have been fixed.
3674 *** Changes in GDB-4.6:
3676 * Better support for C++ function names
3678 GDB now accepts as input the "demangled form" of C++ overloaded function
3679 names and member function names, and can do command completion on such names
3680 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3681 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3682 Make use of command completion, it is your friend.
3684 GDB also now accepts a variety of C++ mangled symbol formats. They are
3685 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3686 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3687 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3688 for the list of formats.
3690 * G++ symbol mangling problem
3692 Recent versions of gcc have a bug in how they emit debugging information for
3693 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3694 directory) can be applied to gcc to fix the problem. Alternatively, if you
3695 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3696 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3697 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3700 * New 'maintenance' command
3702 All of the commands related to hacking GDB internals have been moved out of
3703 the main command set, and now live behind the 'maintenance' command. This
3704 can also be abbreviated as 'mt'. The following changes were made:
3706 dump-me -> maintenance dump-me
3707 info all-breakpoints -> maintenance info breakpoints
3708 printmsyms -> maintenance print msyms
3709 printobjfiles -> maintenance print objfiles
3710 printpsyms -> maintenance print psymbols
3711 printsyms -> maintenance print symbols
3713 The following commands are new:
3715 maintenance demangle Call internal GDB demangler routine to
3716 demangle a C++ link name and prints the result.
3717 maintenance print type Print a type chain for a given symbol
3719 * Change to .gdbinit file processing
3721 We now read the $HOME/.gdbinit file before processing the argv arguments
3722 (e.g. reading symbol files or core files). This allows global parameters to
3723 be set, which will apply during the symbol reading. The ./.gdbinit is still
3724 read after argv processing.
3726 * New hosts supported
3728 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3730 GNU/Linux support i386-unknown-linux or linux
3732 We are also including code to support the HP/PA running BSD and HPUX. This
3733 is almost guaranteed not to work, as we didn't have time to test or build it
3734 for this release. We are including it so that the more adventurous (or
3735 masochistic) of you can play with it. We also had major problems with the
3736 fact that the compiler that we got from HP doesn't support the -g option.
3739 * New targets supported
3741 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3743 * More smarts about finding #include files
3745 GDB now remembers the compilation directory for all include files, and for
3746 all files from which C is generated (like yacc and lex sources). This
3747 greatly improves GDB's ability to find yacc/lex sources, and include files,
3748 especially if you are debugging your program from a directory different from
3749 the one that contains your sources.
3751 We also fixed a bug which caused difficulty with listing and setting
3752 breakpoints in include files which contain C code. (In the past, you had to
3753 try twice in order to list an include file that you hadn't looked at before.)
3755 * Interesting infernals change
3757 GDB now deals with arbitrary numbers of sections, where the symbols for each
3758 section must be relocated relative to that section's landing place in the
3759 target's address space. This work was needed to support ELF with embedded
3760 stabs used by Solaris-2.0.
3762 * Bug fixes (of course!)
3764 There have been loads of fixes for the following things:
3765 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3766 i960, stabs, DOS(GO32), procfs, etc...
3768 See the ChangeLog for details.
3770 *** Changes in GDB-4.5:
3772 * New machines supported (host and target)
3774 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3776 SGI Irix-4.x mips-sgi-irix4 or iris4
3778 * New malloc package
3780 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3781 Mmalloc is capable of handling mutiple heaps of memory. It is also
3782 capable of saving a heap to a file, and then mapping it back in later.
3783 This can be used to greatly speedup the startup of GDB by using a
3784 pre-parsed symbol table which lives in a mmalloc managed heap. For
3785 more details, please read mmalloc/mmalloc.texi.
3789 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3790 'help info proc' for details.
3792 * MIPS ecoff symbol table format
3794 The code that reads MIPS symbol table format is now supported on all hosts.
3795 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3798 * File name changes for MS-DOS
3800 Many files in the config directories have been renamed to make it easier to
3801 support GDB on MS-DOSe systems (which have very restrictive file name
3802 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3803 environment) is close to working but has some remaining problems. Note
3804 that debugging of DOS programs is not supported, due to limitations
3805 in the ``operating system'', but it can be used to host cross-debugging.
3807 * Cross byte order fixes
3809 Many fixes have been made to support cross debugging of Sparc and MIPS
3810 targets from hosts whose byte order differs.
3812 * New -mapped and -readnow options
3814 If memory-mapped files are available on your system through the 'mmap'
3815 system call, you can use the -mapped option on the `file' or
3816 `symbol-file' commands to cause GDB to write the symbols from your
3817 program into a reusable file. If the program you are debugging is
3818 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3819 Future GDB debugging sessions will notice the presence of this file,
3820 and will quickly map in symbol information from it, rather than reading
3821 the symbol table from the executable program. Using the '-mapped'
3822 option in a GDB `file' or `symbol-file' command has the same effect as
3823 starting GDB with the '-mapped' command-line option.
3825 You can cause GDB to read the entire symbol table immediately by using
3826 the '-readnow' option with any of the commands that load symbol table
3827 information (or on the GDB command line). This makes the command
3828 slower, but makes future operations faster.
3830 The -mapped and -readnow options are typically combined in order to
3831 build a `fred.syms' file that contains complete symbol information.
3832 A simple GDB invocation to do nothing but build a `.syms' file for future
3835 gdb -batch -nx -mapped -readnow programname
3837 The `.syms' file is specific to the host machine on which GDB is run.
3838 It holds an exact image of GDB's internal symbol table. It cannot be
3839 shared across multiple host platforms.
3841 * longjmp() handling
3843 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3844 siglongjmp() without losing control. This feature has not yet been ported to
3845 all systems. It currently works on many 386 platforms, all MIPS-based
3846 platforms (SGI, DECstation, etc), and Sun3/4.
3850 Preliminary work has been put in to support the new Solaris OS from Sun. At
3851 this time, it can control and debug processes, but it is not capable of
3856 As always, many many bug fixes. The major areas were with g++, and mipsread.
3857 People using the MIPS-based platforms should experience fewer mysterious
3858 crashes and trashed symbol tables.
3860 *** Changes in GDB-4.4:
3862 * New machines supported (host and target)
3864 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3866 BSD Reno on Vax vax-dec-bsd
3867 Ultrix on Vax vax-dec-ultrix
3869 * New machines supported (target)
3871 AMD 29000 embedded, using EBMON a29k-none-none
3875 GDB continues to improve its handling of C++. `References' work better.
3876 The demangler has also been improved, and now deals with symbols mangled as
3877 per the Annotated C++ Reference Guide.
3879 GDB also now handles `stabs' symbol information embedded in MIPS
3880 `ecoff' symbol tables. Since the ecoff format was not easily
3881 extensible to handle new languages such as C++, this appeared to be a
3882 good way to put C++ debugging info into MIPS binaries. This option
3883 will be supported in the GNU C compiler, version 2, when it is
3886 * New features for SVR4
3888 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3889 shared libraries. Debugging dynamically linked programs should present
3890 only minor differences from debugging statically linked programs.
3892 The `info proc' command will print out information about any process
3893 on an SVR4 system (including the one you are debugging). At the moment,
3894 it prints the address mappings of the process.
3896 If you bring up GDB on another SVR4 system, please send mail to
3897 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3899 * Better dynamic linking support in SunOS
3901 Reading symbols from shared libraries which contain debugging symbols
3902 now works properly. However, there remain issues such as automatic
3903 skipping of `transfer vector' code during function calls, which
3904 make it harder to debug code in a shared library, than to debug the
3905 same code linked statically.
3909 GDB is now using the latest `getopt' routines from the FSF. This
3910 version accepts the -- prefix for options with long names. GDB will
3911 continue to accept the old forms (-option and +option) as well.
3912 Various single letter abbreviations for options have been explicity
3913 added to the option table so that they won't get overshadowed in the
3914 future by other options that begin with the same letter.
3918 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3919 Many assorted bugs have been handled. Many more remain to be handled.
3920 See the various ChangeLog files (primarily in gdb and bfd) for details.
3923 *** Changes in GDB-4.3:
3925 * New machines supported (host and target)
3927 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3928 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3929 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3931 * Almost SCO Unix support
3933 We had hoped to support:
3934 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3935 (except for core file support), but we discovered very late in the release
3936 that it has problems with process groups that render gdb unusable. Sorry
3937 about that. I encourage people to fix it and post the fixes.
3939 * Preliminary ELF and DWARF support
3941 GDB can read ELF object files on System V Release 4, and can handle
3942 debugging records for C, in DWARF format, in ELF files. This support
3943 is preliminary. If you bring up GDB on another SVR4 system, please
3944 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3949 GDB now uses the latest `readline' library. One user-visible change
3950 is that two tabs will list possible command completions, which previously
3951 required typing M-? (meta-question mark, or ESC ?).
3955 The `stepi' bug that many of you noticed has been squashed.
3956 Many bugs in C++ have been handled. Many more remain to be handled.
3957 See the various ChangeLog files (primarily in gdb and bfd) for details.
3959 * State of the MIPS world (in case you wondered):
3961 GDB can understand the symbol tables emitted by the compilers
3962 supplied by most vendors of MIPS-based machines, including DEC. These
3963 symbol tables are in a format that essentially nobody else uses.
3965 Some versions of gcc come with an assembler post-processor called
3966 mips-tfile. This program is required if you want to do source-level
3967 debugging of gcc-compiled programs. I believe FSF does not ship
3968 mips-tfile with gcc version 1, but it will eventually come with gcc
3971 Debugging of g++ output remains a problem. g++ version 1.xx does not
3972 really support it at all. (If you're lucky, you should be able to get
3973 line numbers and stack traces to work, but no parameters or local
3974 variables.) With some work it should be possible to improve the
3977 When gcc version 2 is released, you will have somewhat better luck.
3978 However, even then you will get confusing results for inheritance and
3981 We will eventually provide full debugging of g++ output on
3982 DECstations. This will probably involve some kind of stabs-in-ecoff
3983 encapulation, but the details have not been worked out yet.
3986 *** Changes in GDB-4.2:
3988 * Improved configuration
3990 Only one copy of `configure' exists now, and it is not self-modifying.
3991 Porting BFD is simpler.
3995 The `step' and `next' commands now only stop at the first instruction
3996 of a source line. This prevents the multiple stops that used to occur
3997 in switch statements, for-loops, etc. `Step' continues to stop if a
3998 function that has debugging information is called within the line.
4002 Lots of small bugs fixed. More remain.
4004 * New host supported (not target)
4006 Intel 386 PC clone running Mach i386-none-mach
4009 *** Changes in GDB-4.1:
4011 * Multiple source language support
4013 GDB now has internal scaffolding to handle several source languages.
4014 It determines the type of each source file from its filename extension,
4015 and will switch expression parsing and number formatting to match the
4016 language of the function in the currently selected stack frame.
4017 You can also specifically set the language to be used, with
4018 `set language c' or `set language modula-2'.
4022 GDB now has preliminary support for the GNU Modula-2 compiler,
4023 currently under development at the State University of New York at
4024 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4025 continue through the fall of 1991 and into 1992.
4027 Other Modula-2 compilers are currently not supported, and attempting to
4028 debug programs compiled with them will likely result in an error as the
4029 symbol table is read. Feel free to work on it, though!
4031 There are hooks in GDB for strict type checking and range checking,
4032 in the `Modula-2 philosophy', but they do not currently work.
4036 GDB can now write to executable and core files (e.g. patch
4037 a variable's value). You must turn this switch on, specify
4038 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4039 by assigning a new value to a variable. Modifications take
4042 * Automatic SunOS shared library reading
4044 When you run your program, GDB automatically determines where its
4045 shared libraries (if any) have been loaded, and reads their symbols.
4046 The `share' command is no longer needed. This also works when
4047 examining core files.
4051 You can specify the number of lines that the `list' command shows.
4054 * New machines supported (host and target)
4056 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4057 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4058 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4060 * New hosts supported (not targets)
4062 IBM RT/PC: romp-ibm-aix or rtpc
4064 * New targets supported (not hosts)
4066 AMD 29000 embedded with COFF a29k-none-coff
4067 AMD 29000 embedded with a.out a29k-none-aout
4068 Ultracomputer remote kernel debug a29k-nyu-kern
4070 * New remote interfaces
4076 *** Changes in GDB-4.0:
4080 Wide output is wrapped at good places to make the output more readable.
4082 Gdb now supports cross-debugging from a host machine of one type to a
4083 target machine of another type. Communication with the target system
4084 is over serial lines. The ``target'' command handles connecting to the
4085 remote system; the ``load'' command will download a program into the
4086 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4087 also supports debugging of realtime processes running under VxWorks,
4088 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4089 stub on the target system.
4091 New CPUs supported include the AMD 29000 and Intel 960.
4093 GDB now reads object files and symbol tables via a ``binary file''
4094 library, which allows a single copy of GDB to debug programs of multiple
4095 object file types such as a.out and coff.
4097 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4098 refcard.dvi and refcard.ps are available to format it).
4101 * Control-Variable user interface simplified
4103 All variables that control the operation of the debugger can be set
4104 by the ``set'' command, and displayed by the ``show'' command.
4106 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4107 ``Show prompt'' produces the response:
4108 Gdb's prompt is new-gdb=>.
4110 What follows are the NEW set commands. The command ``help set'' will
4111 print a complete list of old and new set commands. ``help set FOO''
4112 will give a longer description of the variable FOO. ``show'' will show
4113 all of the variable descriptions and their current settings.
4115 confirm on/off: Enables warning questions for operations that are
4116 hard to recover from, e.g. rerunning the program while
4117 it is already running. Default is ON.
4119 editing on/off: Enables EMACS style command line editing
4120 of input. Previous lines can be recalled with
4121 control-P, the current line can be edited with control-B,
4122 you can search for commands with control-R, etc.
4125 history filename NAME: NAME is where the gdb command history
4126 will be stored. The default is .gdb_history,
4127 or the value of the environment variable
4130 history size N: The size, in commands, of the command history. The
4131 default is 256, or the value of the environment variable
4134 history save on/off: If this value is set to ON, the history file will
4135 be saved after exiting gdb. If set to OFF, the
4136 file will not be saved. The default is OFF.
4138 history expansion on/off: If this value is set to ON, then csh-like
4139 history expansion will be performed on
4140 command line input. The default is OFF.
4142 radix N: Sets the default radix for input and output. It can be set
4143 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4144 in the current radix, so "set radix 10" is always a no-op.
4146 height N: This integer value is the number of lines on a page. Default
4147 is 24, the current `stty rows'' setting, or the ``li#''
4148 setting from the termcap entry matching the environment
4151 width N: This integer value is the number of characters on a line.
4152 Default is 80, the current `stty cols'' setting, or the ``co#''
4153 setting from the termcap entry matching the environment
4156 Note: ``set screensize'' is obsolete. Use ``set height'' and
4157 ``set width'' instead.
4159 print address on/off: Print memory addresses in various command displays,
4160 such as stack traces and structure values. Gdb looks
4161 more ``symbolic'' if you turn this off; it looks more
4162 ``machine level'' with it on. Default is ON.
4164 print array on/off: Prettyprint arrays. New convenient format! Default
4167 print demangle on/off: Print C++ symbols in "source" form if on,
4170 print asm-demangle on/off: Same, for assembler level printouts
4173 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4176 * Support for Epoch Environment.
4178 The epoch environment is a version of Emacs v18 with windowing. One
4179 new command, ``inspect'', is identical to ``print'', except that if you
4180 are running in the epoch environment, the value is printed in its own
4184 * Support for Shared Libraries
4186 GDB can now debug programs and core files that use SunOS shared libraries.
4187 Symbols from a shared library cannot be referenced
4188 before the shared library has been linked with the program (this
4189 happens after you type ``run'' and before the function main() is entered).
4190 At any time after this linking (including when examining core files
4191 from dynamically linked programs), gdb reads the symbols from each
4192 shared library when you type the ``sharedlibrary'' command.
4193 It can be abbreviated ``share''.
4195 sharedlibrary REGEXP: Load shared object library symbols for files
4196 matching a unix regular expression. No argument
4197 indicates to load symbols for all shared libraries.
4199 info sharedlibrary: Status of loaded shared libraries.
4204 A watchpoint stops execution of a program whenever the value of an
4205 expression changes. Checking for this slows down execution
4206 tremendously whenever you are in the scope of the expression, but is
4207 quite useful for catching tough ``bit-spreader'' or pointer misuse
4208 problems. Some machines such as the 386 have hardware for doing this
4209 more quickly, and future versions of gdb will use this hardware.
4211 watch EXP: Set a watchpoint (breakpoint) for an expression.
4213 info watchpoints: Information about your watchpoints.
4215 delete N: Deletes watchpoint number N (same as breakpoints).
4216 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4217 enable N: Re-enables watchpoint number N (same as breakpoints).
4220 * C++ multiple inheritance
4222 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4225 * C++ exception handling
4227 Gdb now supports limited C++ exception handling. Besides the existing
4228 ability to breakpoint on an exception handler, gdb can breakpoint on
4229 the raising of an exception (before the stack is peeled back to the
4232 catch FOO: If there is a FOO exception handler in the dynamic scope,
4233 set a breakpoint to catch exceptions which may be raised there.
4234 Multiple exceptions (``catch foo bar baz'') may be caught.
4236 info catch: Lists all exceptions which may be caught in the
4237 current stack frame.
4240 * Minor command changes
4242 The command ``call func (arg, arg, ...)'' now acts like the print
4243 command, except it does not print or save a value if the function's result
4244 is void. This is similar to dbx usage.
4246 The ``up'' and ``down'' commands now always print the frame they end up
4247 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4248 frames without printing.
4250 * New directory command
4252 'dir' now adds directories to the FRONT of the source search path.
4253 The path starts off empty. Source files that contain debug information
4254 about the directory in which they were compiled can be found even
4255 with an empty path; Sun CC and GCC include this information. If GDB can't
4256 find your source file in the current directory, type "dir .".
4258 * Configuring GDB for compilation
4260 For normal use, type ``./configure host''. See README or gdb.texinfo
4263 GDB now handles cross debugging. If you are remotely debugging between
4264 two different machines, type ``./configure host -target=targ''.
4265 Host is the machine where GDB will run; targ is the machine
4266 where the program that you are debugging will run.